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Bone loss and fragility from osteoporosis afflict more than 200 million people worldwide, including at least 10 million Americans. Current osteoporosis treatments are significantly deficient: most fail to reverse bone loss and/or have adverse effects that prohibit their long-term use. New therapeutic approaches are urgently needed. Recently the TGF- family ligand Activin A emerged as an important target in bone loss treatment. Activin A is highly expressed in bone and inhibits bone formation. More importantly, inhibition of Activin A greatly increases bone mass in animal models, demonstrating considerable potential as bone-forming therapy. However, off-target effects of current Activin A inhibitors make their therapeutic use impractical for this indication. To overcome this obstacle, an ideal Activin A inhibitor would retain its bone forming capabilities while minimizing off-target effects. We recently discovered a novel Activin A inhibitor, the extracellular protein `Cryptic'. We found that a `Cryptic' human Igg1-Ffucsion protein (Cryptic-Fc) binds Activin A with picomolar affinity and potently inhibits Activin A signaling. Strikingly, Cryptic-Fc showed greater target specificity than current Activin inhibitors, suggesting that Cryptic-Fc has the desired antagonistic properties. The goal of this phase I proposal is to demonstrate that Cryptic-derived polypeptides can promote bone formation in vivo with limited off-target effects. Successful proof of concept studies will pave th way for pre-clinical development of a Cryptic-derived polypeptide as therapeutic for osteoporosis.
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{
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Normal peripheral blood lymphocytes are being evaluated using dual- color flow cytometry to assess lymphocyte phenotypes. The study also compares two cell preparation methods. This study has been extended to include three-color flow cytometry in normal individuals. Evaluation of additional surface antigens and new lymphocyte subpopulations based on the assessment of three surface antigens simultaneously is in progress. In addition, a comparison of methods for red cell lysis has established that this technique can have an impact on fluorescence intensity and lymphocyte recovery. Extension of these studies to CD34+ hematopoietic progenitor cells identified differences in the effects of red cell lysis in this setting versus the effects of lymphocyte immunophenotyping.
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{
"pile_set_name": "NIH ExPorter"
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Physical models of vascular systems are being used extensively in our laboratory to study a variety of phenomena related to hemodynamics. During the past year, efforts have been directed to projects in the following categories: (1) a study of intra-arterial drug delivery, using a glass model of the pelvic arteries; (2) a study of the effect of fluid shear on the adhesion of monocytes onto cultured endothelial cells; (3) numerical analysis of flow characteristics in branching vessels; (4) investigation of mechanical strength of several types of cardiovascular stents; and (5) study of the injection characteristics and mixing properties of several angiographic catheters, using a glass model of the human aorta.
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{
"pile_set_name": "NIH ExPorter"
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DESCRIPTION: (Taken from the investigator s abstract) Premature Ovarian Failure (POF) affects approximately 10 percent of amenorrheic women, and can be devastating because of the young age of onset, the presumed irreversible infertility, and the long-term consequences of estrogen deficiency. Although certain conditions, including chemo and radiation therapy, and X chromosomal deletions, are known to cause POF, the precise prevalence of the different etiologies is unknown. However, tests for organ specific serum antibody titers by the investigator and others, indicates that up to 50 percent of women with POF may have an underlying autoimmune abnormality. Recently, investigators have identified a functional defect in endogenous presentation of self-peptide fragments in the groove of major histocompatibility complex (MHC) class I molecules in patients with autoimmune disease with linkage to the HLA region. This defect results in decreased cell surface expression of conformationally correct class I antigens. Normally the complex of HLA class I and self peptide selects both positively and negatively T cells. Disruption of this process might explain the lack of self-antigen recognition and of self tolerance that leads to the autoimmune cell destruction in autoimmune diseases. The Tap-1 and Tap-2 intracellular peptide transporter genes, which map to the HLA class II region and control the delivery and association of endogenous peptides with class I molecules, may be responsible for the functional defect. Their preliminary data indicates that this same functional defect of class I antigen presentation is present in women with POF associated with the syndrome of Type II autoimmune polyglandular failure (PFG). Many autoimmune diseases are worse in women, presumably due to immunostimulatory effects of estrogen, but it is not known whether estrogen deficiency or estrogen replacement in women with POF affects the progression of their disease. In this proposal, they plan to capitalize on the collaborative expertise between clinical studies of women with POF in the Reproductive Endocrine Unit and the immunologic developments of the Immunobiology Laboratories. They wish to determine: 1) the prevalence of Tap controlled class I antigen presentation defects in women with POF; 2) the association of class I antigen defects with other manifestations of autoimmune diseases in POF; 3) the role of serum estrogen levels in the expression of autoimmune POF; 4) the efficacy of immunosuppressive therapy in those women with automimmune dysfunction; and 5) the presence and/or the prevalence of Tap-1 and Tap-2 gene defects as the basis of abnormal class I antigen presentation in women with autoimmune POF.
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{
"pile_set_name": "NIH ExPorter"
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Transposition rates of phospholipids in natural membranes will be studied. In addition, the exchangeability of phospholipids in plasma membranes will be investigated. A model for cholesterol absorption from the intestine is under investigation with the intent of testing the hypothesis that transfer of isotopic cholesterol correctly measures cholesterol absorption rates.
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{
"pile_set_name": "NIH ExPorter"
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This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Bacteria secrete a variety of signaling molecules that allow them to coordinate gene expression and behave as multicellular organisms. In response to these 'quorum sensing'or 'autoinducer'signals, such medically important phenotypes as virulence factor expression, biofilm formation, and drug resistance are modulated in a population wide manner. The enzyme 5'Methylthioadenosine / S-adenosylhomocysteine nucleosidase (MTA/SAH nucleosidase, MTN) occupies a central place in the biosynthetic pathways that lead to both autoinducer I (AI-1) and autoinducer II (AI-2) formation. In addition, MTN governs a crucial step in the recycling of methionine and adenine consumed during S-adenosylmethionine dependent polyamine synthesis and methylation reactions. Pharmacologic or genetic inhibition of MTN should block methionine and purine salvage, cause growth delays through the accumulation of inhibitory MTA and SAH nucleosides, and interfere with autoinducer synthesis and downstream signal dependent processes. To examine the role of this enzyme in nutrient salvage and signaling pathways, MTN knock-out strains of E. coli (O157:H7) and Klebsiella pneumoniae will be created and studied for alterations in growth (rate, carbon utilization, biofilm formation), attenuation of mammalian cell invasion in in vitro models of infection, and in murine models of in vivo colonization and virulence. Proteomic and metabolomic adaptations to MTN gene deletion will also be examined by LC/MS and NMR to further characterize the molecular consequences of enzyme interruption and explain the basis for observed alteration in phenotype. Ultimately, these experiments should underscore the importance of cellular signaling in bacteria as a target for novel antibiotic development.
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{
"pile_set_name": "NIH ExPorter"
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Ebola virus disease has emerged as a public health threat of international concern. The objective of this K23 Mentored Patient-Oriented Career Development Award Application is to facilitate the development of essential skills that will allow the principal investigator to become an independent and productive physician-scientist and to address the two primary concerns of Ebola survivors: a) the potential for sexual transmission of the Ebola virus and b) the presence of ongoing clinical sequelae of Ebola virus infection. The Ebola epidemic currently devastating West Africa has evolved into an unprecedented humanitarian crisis. In the forty years since the discovery of the Ebola virus we have been able to learn very little due to the high mortality rates associated with this virus, the low number of survivors, and the austere settings of most outbreaks which limit the ability to do research in the field. The scale of current outbreak and the infrastructure that the principal investigator and his mentor, Dr. Wohl, have put in place will allow them to be able to directly address the concerns listed above by Ebola virus disease (EVD) survivors. The continued shedding of live virus despite recovery from EVD has a number of public health implications including the potential for perpetuation of the epidemic through on going viral transmission. The WHO and CDC recommend abstinence for 7 weeks and 3 months respectively based on data from only 10 subjects. AIM I of this proposal includes a cross sectional study of the presence of Ebola virus by PCR and culture in the semen and vaginal fluid from at least 200 Ebola disease survivors across the spectrum of time from recovery (0-3months, 3-6months, 6-9months, and 9-12months). We will then longitudinally follow the group of survivors most recently discharged from an ETU (0-3 months) to determine the duration of live viral shedding. The proposed studies will thus provide a thorough characterization of viral dynamics in urogenital compartments on which sound public health policies and recommendations can be based. AIM II includes a clinical and psychosocial assessment of survivors in both the cross-sectional and longitudinal aspects of the study. This, along with collection of blood for evaluation of serologic markers of immune activation and inflammation will provide important insight into the clinical sequelae of Ebola virus disease and explore potential associations between ongoing virus replication, systemic inflammation, and Post-Ebola symptoms. Ultimately this study will ensure that the world is prepared for the next epidemic through improved understanding of virus shedding in semen and vaginal fluid, heightened awareness of the clinical complications of Ebola virus disease and the development of the principal investigator as a clinical researcher so that he can not only respond but learn and lead at the same time as a physician and a scientist.
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{
"pile_set_name": "NIH ExPorter"
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[unreadable] [unreadable] This investigation will examine immune, inflammatory, coagulation, and lipid disturbances as potential mediators of increased atherosclerosis in HIV-infected women participating in the Women's Interagency HIV Study (WIHS). Subjects will include 750 HIV-infected and 250 HIV-uninfected women participating in the Follow-up Phase of the WIHS Carotid Artery Ultrasound Study. The set of specific aims include two primary aims: Aim 1 focuses on established inflammation and coagulation biomarkers as predictors of subclinical atherosclerosis. Aim 2 examines lipid changes which constitute "classic" vascular risk factors. Data analysis goals are: (1) To correlate changes in inflammatory and coagulation markers with HIV disease stage and treatments, including initiation of HAART and changes in viremic and CD4+ status; (2) To determine if immune, inflammatory, and coagulation mechanisms contribute to increased atherosclerosis in HIV-infected women; (3) To determine changes in "classic" vascular risk factors (e.g., lipids) over time due to changes in HAART and HIV disease stage, and how this impacts atherosclerosis. In addition, we propose three exploratory aims examining novel immune and inflammatory mediators that may be of importance to atherosclerosis in HIV-infected adults: 1. Translocation of gut microbes, as measured by 16s RNA; 2. T-cell senescence (CD4+CD28- and CD8+CD28- T-cells); 3. T regulatory cells. This investigation will examine immune, inflammatory, coagulation, and lipid disturbances as potential mediators of increased atherosclerosis in HIV-infected women participating in the Women's Interagency HIV Study (WIHS). We will (1) correlate changes in inflammatory and coagulation markers with HIV disease stage and treatments, including initiation of HAART and changes in viremic and CD4+ status; (2) determine if immune, inflammatory, and coagulation mechanisms contribute to increased atherosclerosis in HIV-infected women; and (3) determine changes in "classic" vascular risk factors (e.g., lipids) over time due to changes in HAART and HIV disease stage, and how this impacts atherosclerosis. (End of Abstract) [unreadable] [unreadable] [unreadable]
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{
"pile_set_name": "NIH ExPorter"
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Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that causes motor neuron degeneration, skeletal muscle atrophy, paralysis and death. Our long term objective is to understand the disease mechanism and develop a cure. At present, the only robust model for typical ALS is mice that express mutant SOD1. Recently, a mutation in VAMP associated protein B (VAPB) gene has been identified to cause motor neuron degeneration and ALS. The clinical symptom of ALS as a result of the VAPB mutation is variable and includes both typical and atypical cases. All, however, is adult onset. Based on in vitro data, the predominant hypothesis regarding the mechanism whereby mutant VAPB induces ALS is that the mutation leads to a dominant negative activity. However, no in vivo data is available. In addition, other possibilities, such as dominant gain-of-function and loss-of-function have not been ruled out. We propose to differentiate these three possibilities using transgenic approaches to overexpress the mutant VAPB and to silence the mouse VAPB using transgenic RNAi. The combined data from these two approaches will unequivocally determine which one of these three mechanisms is true. Because our transgenic constructs are designed to be Cre-inducible, these transgenic mice can be used to investigate the roles of mutant VAPB expression in motor neuron and non-motor neuron cells in the future by crossing with mice that express Cre in various specific cells (neurons, glia and microglia). Furthermore, we propose complementary experiments in cultured cells to dissect the function of VAPB and the altered function in mutant VAPB. These experiments will enhance our understanding of mechanisms of motor neuron degeneration and establish a second line of adult onset transgenic model for ALS, which can be used for preclinical analysis of therapeutic strategies for ALS. RELEVANCE: A VAPB gene mutation causes amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease without a cure. We propose to establish cell culture and transgenic mouse models to investigate how the VAPB mutation causes neuronal degeneration. Once established, these models can be used for pre-clinical tests of therapeutic compounds.
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{
"pile_set_name": "NIH ExPorter"
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Methamphetamine (MIETH) is a highly addictive drug of abuse that has also raised concern since in laboratory animals it is neurotoxic to dopamine (DA) terminals. Moreover, recent imaging and postmortem studies in MIETH abusers have documented marked reductions in DA transporters (DAT), which serve as markers of DA terminals. However, the extent to which the DAT reductions in METH abusers are associated with abnormal DA cell function, the extent to which these changes may recover with detoxification and the extent to which they contribute to the addictive process have not been evaluated. In this competitive renewal we propose to assess whether the DAT losses in METH abusers are associated with disrupted DA cell function and to assess if they recover with detoxification. We will use positron emission tomography (PET) to measure DAT using 'C]cocaine (DAT radioligand) and to assess DA cell function by comparing the binding of raclopride (DA D2 radioligand whose binding to D2 receptors is sensitive to competition by endogenous DA) with and without pretreatment with methyiphenidate (drug that increases DA by blocking DAT). We propose to test METH abusers (n = 40) during early withdrawal (greater than 2 weeks and less than 3 months), and retest them 6-9 months later after a drug free period (we expect 10 abusers to return for testing). Normal controls (n = 20) will be tested in parallel and 10 of them will be retested 6-9 months later to assess reproducibility. Our working hypotheses are: (1) MIETH abusers will have decreased function of DA cells in addition to the loss of DAT (2) Detoxification will result in increase in DA cell function and in DAT levels. It is important to assess if there is disrupted DA cell function in METH abusers since it could perpetuate METH use as a means to temporarily compensate for this dysfunction. It is also of relevance to determine if it recovers with detoxification in order to understand the long-term consequences of DAT losses in the METH abusers vis a vis their vulnerability to neurodegenerative diseases (i.e Parkinson's disease). Such knowledge should help guide the management of the METH abuser and the development of medications that may help ameliorate the DA deficits.
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{
"pile_set_name": "NIH ExPorter"
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The goal of this research project is to investigate the intermolecular interactions and mechanism of electron transfer between cytochrome c and cytochrome oxidase and reductase. Semi-synthetic analogs of cytochrome c will be constructed by combining cyanogen bromide fragments 1-65 and 81-104, prepared from natural cytochrome c, with synthetic peptides corresponding to residues 66-80, prepared by solid phase peptide synthesis. The latter sequence contains most of the amino acids which are thought to be mechanistically important, and thus, we plan to test various proposed mechanisms by replacing supposedly important amino acids with different amino acids which could not function in the same manner. Other synthetic analogs will be designed to investigate the relationship of the oxidation-reduction potential of cytochrome c to its amino acid sequences and tertiary structure. Efforts will be made to determine which amino acids participate in the interactions of cytochrome c with cytochrome oxidase and cytochrome c reductase by introducing amino acid substitutions which weaken or inhibit these interactions. The chemical purity of the synthetic cytochrome c analogs will be carefully analyzed, and their oxidation-reduction potentials and their visible, ultraviolet and circular dichroism spectra will be compared with the corresponding properties of natural cytochrome c. The biological activities of the synthetic analogs will be determined in several different electron transport assay systems, including the Keilin-Hartree heart muscle preparation, and the related NADH-cytochrome c reductase and cytochrome oxidase systems. Our studies of the specific interactions of cytochrome c analogs with the oxidase and reductase complexes isolated from heart mitochondria should provide a more detailed understanding of the intricate relations among these important components of the respiratory electron transport chain, which produces the ATP required to sustain normal heart activity.
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{
"pile_set_name": "NIH ExPorter"
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Latino communities have been disproportionately impacted by the HIV/AIDS epidemic, especially Latino gay and bisexual men and transgender persons (GBT). The stigma towards homosexuality and HIV/AIDS has been proposed as one of the underlying factors leading to unprotected sex, hence, to HIV and AIDS. The stigma towards homosexuality and HIV/AIDS may put individuals at risk for HIV because of its negative impact on the self, because it may diminish social support, and because it may prevent individuals from accessing resources. Despite the decline in negative societal attitudes towards homosexuality and HIV/AIDS in the U.S., gay men continue to experience stigmatization. Unfortunately, research and intervention activities focused on stigma are limited. The overall goal of our research activities is to reduce HIV and AIDS among Latino GET. The goal of this Phase II project, thus, is to produce and test an educational documentary film to decrease stigma towards homosexuality and HIV/AIDS as a means to prevent HIV-risk behaviors among Latino GET. The specific aims include: 1. To produce an educational documentary film. The primary target audience for this film is Latino youth between the ages of 14 and 24. The secondary audiences include Latino adults; and members of the gay, bisexual, lesbian, and transgender communities. 2. To develop a discussion guide for use with the educational film. 3. To evaluate the educational film through a pre-post test of stigmatizing attitudes towards homosexuality and HIV/AIDS among a segment of our primary audience. Our commercialization plan, which includes national television broadcast, educational distribution, and local community outreach, will help make this film widely available among Spanish and English speaking Latino and GET audiences.
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{
"pile_set_name": "NIH ExPorter"
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The Toxicology Graduate Program at the University of Arizona has a long-standing reputation for excellence in training Ph.D. scientist. Many of our graduates are now leaders in academia, industry, and government. Current trainees are now selected through a University-wide competition. The graduate program has evolved from a systems-based toxicology experience to training students to apply state-of-the art techniques to solve mechanisms of environmental toxicity affecting complex diseases in various organ systems. The cutting-edge basic science research programs of 22 Training Grant Faculty members, state-of-the-art technologies developed at the University of Arizona in association with the Southwest Environmental Health Sciences Center and Bio5, and translational approaches undertaken by our NIEHS Superfund Program and US-Mexico Binational Center provide an exceptionally stimulating environment for the training of graduate students and postdoctoral fellows. The interactive research of our Training Grant Faculty and our state-of-the-art Facility Cores extend the training environment from a single laboratory-oriented domain into a multidisciplinary experience strongly supportive of collaborative research. The University provides financial support for first year Ph.D. students, providing a large pool of highly qualified candidates for competitive selection of predoctoral trainees. Predoctoral training is achieved through a combination of coursework, laboratory research, and supplemental enrichment activities. Postdoctoral trainees participate in innovative research programs and are guided to develop professional skills in oral and written communication and in supervision. Over past five years, the curricular changes parallel the evolving expertise of the Training Grant Faculty in utilizing state-of-the-art technology for research projects. We have recruited 3 senior (Professor) and 3 junior (Assistant Professor) faculty into the Training Grant, which significantly enhances the strength in the core of mechanistic based molecular toxicology training. We have opened the Training Grant for University-wide selection to further stimulate interdisciplinary/multidisciplinary approaches in research and training. The request for continuation of NIEHS support is validated by the highly successful nature of our program, the clear demand for our graduates, the strong emphasis we place on leadership skills for our trainees and postdoctoral fellows, the increasing number of students interested in toxicology, substantial institutional commitment, strong and well-funded research programs of our faculty, and the excellence of the training environment. PUBLIC HEALTH RELEVANCE: This training grant seeks the support from NIEHS for 9 predoctoral and 3 postdoctoral fellows in training of toxicology at the University of Arizona.
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{
"pile_set_name": "NIH ExPorter"
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Breast cancer incidence and mortality are higher in young African American women than in young white women. Little data exist regarding the responses of poor women and women of color to the cancer experience. However, anecdotal information and data from focus groups suggest that these women need information about cancer and its treatment, and how to interact with the medical care system, including communicating with physicians. Our multi-disciplinary, multi-cultural team proposes to design, implement and evaluate the effectiveness of a ten session education support group targeted for women under 50 who are African American, Hispanic, Filipino, Chinese or white living in the San Francisco Bay Area. The focus of the intervention is information on cancer and its treatment, and on coping skills training. The sample will be recruited from the population-based SEER tumor registry using rapid identification procedures which will allow us to reach this group of women as soon as six weeks following their diagnosis for breast cancer. We will stratify (by ethnicity) and randomly assign 200 women to the education support group intervention and 200 women to a non-intervention control group. Women in the control group will receive information about resources in their community. Outcome data include measures of psychosocial distress, self-image including sexuality, physical functioning including return to work, and compliance with medical treatment. To guide our approach, make it culturally sensitive, and determine the best time for the intervention, we will first mount a descriptive population-based survey which will include all women under age 50 diagnosed with breast cancer during a six month period. We anticipate a sample of 360 women; half will be interviewed within the first three months of diagnosis and the other half between five and seven months after diagnosis. In addition, five ethnically matched focus groups will be conducted to gather qualitative data. The significance of approach lies in targeting a culturally diverse population, providing a potentially cost- effective intervention which has been designed to be culturally sensitive by a multi-ethnic, multi-disciplinary team.
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{
"pile_set_name": "NIH ExPorter"
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Despite continued improvement in the technical aspects of cardiopulmonary bypass procedures, a majority of cardiac surgical patients demonstrate postoperative cognitive deficits and three percent actually suffer frank strokes. Although it is not yet proven, the majority of researchers believe that these deficits are caused by emboli.In order to directly correlate the occurrence of neurologic and neuropsychologic deficits with intraoperative cerebral embolic events, it is essentialto be able to measure the occurrence of emboli traveling toward the brain.The applicants have proposed to develop a practical, cost effective instrument which would be able to intraoperatively monitor emboli. To achieve this goal, they have proposed to design a specialized ultrasonic detector which would have a very large effective field of view. Dedicated hardware will be designed that will be capable of analyzing the reflected power level and the audio frequency spectrum needed to count and characterize the emboli. Digital filtering and anti-coincidence techniques will be applied to eliminate the effects of spurious signals. Software will be developed to allow the rapid andaccurate analysis of embolic events under clinical conditions. A clinical prototype will be fabricated and used to study cardiac surgery patients at the Bowman Gray School of Medicine. By this approach, the measuring probe could be positioned against the patient and continuously monitor the emboli count without the constant attention of a skilled operator.
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{
"pile_set_name": "NIH ExPorter"
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Although excess lipid accumulation in non-adipose tissues is initially well tolerated, this metabolic excess ultimately causes cell dysfunction and cell death that is linked to the pathogenesis of complications of diabetes and obesity. Using a genetic screen, we discovered that RNASET2, a T2 endoribonuclease, is a critical mediator of oxidative stress damage and cell death in response to lipotoxicity. This study will elucidate the mechanism of action of RNASET2, by identifying the RNAs that this enzyme degrades, by elucidating the pathways through which RNA substrates are delivered to RNASET2, and by examining the contributions of RNASET2 to the pathogenesis of cardiac lipotoxicity in a mouse model. The results of these studies will provide new insights into the lipotoxic response to excess lipid accumulation in cardiovascular complications of metabolic diseases.
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{
"pile_set_name": "NIH ExPorter"
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DESCRIPTION: Human malaria caused by Plasmodium parasites strikes over 200 million people a year, leading to ~1 million deaths a year. This disease is particularly damaging to children, with one child one every minute succumbing to the disease in Africa (World Health Organization). Glucose metabolism is critical to the success of the intra- erthyrocytic disease-causing lifecycle stages of the P. falciparum, the most virulent species of the parasite. The goal of this application is to identify inhibitor probes of the first enzyme in glycolysis in the parasie, P. falciparum hexokinase (PfHK), through a high throughput screening campaign in collaboration with the NIH National Center for Advancing Translational Sciences (NCATS). We will systematically confirm the inhibitory activity of primary hits using a series of standardized secondary confirmation assays with hits being scored for anti-parasitic activity. Through an iterative approach that weighs activity against enzyme and parasite based on structural modifications, a probe will be identified that is a potent inhibitor of PfHK with promising anti- malarial activity.
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{
"pile_set_name": "NIH ExPorter"
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The goal of the Neurodegeneration Training Program (NTP) is to provide rigorous pre-doctoral training in various aspects of neurodegeneration and mechanisms of diseases involving neurodegeneration. An outstanding pool of trainees will combine with world-class faculty to investigate a wide range of neurodegeneration-related topics spanning research areas such as protein structure, cell and molecular biology and in vitro and in vivo models of disease. The NTP spans departments, schools and institutions to include multiple departments at Case Western Reserve University, particularly the School of Medicine, and its affiliated institutions, University Hospitals Case Medical Center (UHCMC), The Louis Stokes Cleveland Veteran's Administration Medical Center (VAMC), and the Cleveland Clinic Foundation (CCF, including the Lerner Research Institute). All of these institutions are within walking distance of each other and this rich training environment enjoys very active basic science and clinical activities and state of the art resources to enrich the training of pre- doctoal trainees as they engage in basic and/or translational research in the field of neurodegeneration. Training in the NTP involves NTP course work, formal and informal seminars, an annual retreat, and a research experience resulting in scholarly publications. A unique component of this training program is the inclusion of a required 1 semester, half day per week, mentored experience in a neurodegenerative disease clinic. The combination of didactic and experiential training opportunities afforded by the NTP will provide trainees a solid foundation for a future career in the scientific inquiry of neurodegeneration.
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{
"pile_set_name": "NIH ExPorter"
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We plan to study the organization and expression of various mammalian polypeptide hormone gene systems: namely insulin; the glycoprotein hormones (chorionic gonadotropin, luteinizing hormone, follicle stimulating hormone, and thyroid stimulating hormone); and the growth hormone related proteins (growth hormone, chorionic somatomammotropin and prolactin). Both cDNA and genomic clones will be isolated from specific human and rat tissues using recombinant DNA methods and analyzed by nucleotide sequence analysis. The coding and noncoding regions (5' and 3' untranslated and intervening sequences) of related genes will be compared within and between species. The location(s) of the genes will be mapped by hybridization analysis of restriction endonuclease digests of cloned DNA isolated from bacteriophage lambda and cosmid gene libraries and also DNA from metaphase chromosomes separated with a fluorescence activated cell sorter. The cloned DNAs will be used as molecular hybridization probes to study the expression in cultured cells of the hormone genes in response to external stimuli, such as other hormones. Putative control regions in the cloned genes will be mutated in vitro by chemical, enzymatic, and/or oligonucleotide methods and introduced back into mammalian cells by cell transformation or by using SV40 as a vector. The expression of the "wild type" and various mutant genes in normally producing and non-producing recipient cells (e.g. growth hormone in GC versus HTC rat cells) will be measured using nucleic acid hybridization (for both DNA and RNA) and protein detection (polyacrylamide gel electrophoresis and immunological) methods. Other projects include studies on the structure and replication of the retrovirus genome and the isolation of the purine nucleoside phosphorylase gene and its expression in purine nucleoside phosphorylase deficient mouse teratocarcinoma cells.
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{
"pile_set_name": "NIH ExPorter"
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Here we shall test the hypothesis that the retinal rod disk membrane lipid constituents govern visual function through their influences on signaling and amplification processes involving rhodopsin. Emphasis will be placed on the role of the membrane environment in modulating the Meta I-Meta II equilibrium, which is the signaling event in visual excitation. The retinal rod disk membranes are extraordinarily abundant in phospholipids containing highly polyunsaturated fatty acids, including docosahexaenoic acid (DHA;22:6-omega-3) and arachidonic acid (20:4-omega-6). Alterations of visual function are found to occur in essential fatty acid deficiency. Biophysical methods will characterize the influences of membrane lipids on the Meta I}Meta II transition of rhodopsin. Specific Aims are to apply a multidisciplinary approach to (1) identify the membrane lipids that function as agonists or antagonists of rhodopsin signaling;(2) elucidate the properties of membrane lipid bilayers that influence the photochemical function of rhodopsin;(3) illuminate the role of lipid polyunsaturation in rhodopsin activation;(4) discover how electrostatic properties of the membrane govern rhodopsin activation;and (5) establish how the membrane lipid influences on rhodopsin are amplified in visual signaling. A time-resolved multi-wavelength approach based on an optical multi-channel analyzer (OMA) will be used to study the kinetics and mechanism of rhodopsin activation. In addition, Fourier transform infrared (FTIR), fluorescence resonance energy transfer (FRET), and plasmon waveguide resonance (PWR) spectroscopy will elucidate the retinal environment, protein conformation, and oligomerization or association of rhodopsin in the dark, Meta I, and Meta II states. A new flexible surface model (FSM) will provide a framework for understanding how the signaling function of rhodopsin is driven by non-specific properties of the membrane phospholipids, including membrane lipid curvature and hydrophobic forces within the bilayer. The FSM describes the lipid-protein interactions in terms of a balance of the curvature deformation energy, due to elastic stress/strain of the bilayer, with the solvation energy of the proteolipid interface. An additional aspect entails the interplay of the bilayer electrostatics including the surface charge density and the electrical double layer with the above bilayer properties. The influences of polyunsaturated membrane phospholipids on later amplification stages of the visual photoresponse will be investigated, including the binding and activation of the G protein (transducin) to photolyzed rhodopsin, and subsequent activation of cGMP phosphodiesterase. In this manner, a truly comprehensive picture of the triggering and amplification steps of the visual process will be provided at the membrane level in relation to dietary investigations of essential ?3 fatty acid deficiency in humans. PUBLIC HEALTH RELEVANCE: The proposed research will investigate the molecular basis for essential fatty acid deficiency in the retina, which is part of the brain and comprises a uniquely accessible model for the mammalian nervous system. Current knowledge indicates that long chain polyunsaturated fatty acids derived from essential ?3 fatty acids play an important role in retinal and brain development involving human infants. Moreover, polyunsaturated lipids are involved in diseases such as Parkinson's disease, cardiovascular disease, cancer, aging, and other physiological and pathological anomalies. The proposed in vitro studies of the influence of the membrane lipid bilayer on rhodopsin activity will test a specific framework for explaining the effects of essential fatty acid) deficiency in the visual system at the membrane level. This work is pertinent to the role of polyunsaturated lipids in the function and dysfunction of central nervous system of humans with attendant insights that may be of eventual therapeutic benefit.
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{
"pile_set_name": "NIH ExPorter"
}
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This research project deals with the photophysics of photodynamic therapy (PDT) utilizing coherent and noncoherent light and it's tissue transport to PDT cancer treatment sites. Our objectives are to quantitate the processes of scatter, reflection, refraction and absorbance in tissue and learn how these principles may be utilized. We have begun to develop procedures for the estimation and delivery of a uniform, efficient photon light dosage so that tumor oblation may occur without damage to normal tissue. We have studied the red region and the visible band from both laser and incoherent sources, coupling laser beams to fiberoptics for instillation and using beam expanders and incoherent sources for external light delivery. We have compiled transmittance and spectral data on many mammalian tissues at PDT wavelengths, and for the 400 to 1100 nm band have established penetration depths across this region for several tissues. We are extending this research. Study has been carried out in tissue, on simulators, and with tissue phantoms. A series of mammalian tissues is being studied across species boundaries. Species similarities and variations have been established. This cross-species investigation continues and will include human specimens during a later research phase. The ultimate goal is establishment of a photon dosage prediction system for all tissue, tumor types, for photon energies, and sources. We are developing a method of experimentally determining space irradiance, describing the level and extent of light diffusion through a three dimensional tissue volume. Our experimental results in three dimensions, to date, show a basic exponential form. This finding, which supports some of the proposed theoretical models, developed by ourselves and others, is the result of the first systematic series of measurements in 3-D tissue volumes. Additionally, work will be carried out concurrently on a theoretical base for the prediction of transport of light through tissue. Applications of the diffusion and Kubelka-Monk equations are being made to interpret our experimental data. We shall expand our determinations of tissue refraction for selected wavelengths, and of scattering and adsorption coefficients. We have developed several computer programs to aid in the experimental and theoretical work and they are now in use. Basic data generated by this study will be used to develop a light dosage planning system for PDT clinical use.
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{
"pile_set_name": "NIH ExPorter"
}
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This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall, long-term goal of our research is to examine how aging alters skeletal muscle function in humans at the molecular level. The purpose of this submission is to obtain approval to perform muscle function measurements on a population of young (21-35 yrs old, n=24) and elderly (65-75 yrs old, n=24) volunteers in order to complete two goals of a funded NIH K01 grant. 1) Objectives (Specific Aims of the NIH K01 Grant): Age-related reductions in muscle mass and performance, or sarcopenia, decrease a person's ability to perform everyday tasks and increase their risk of falling and fall-related injuries. A key predictor of this decrease in functional capacity is a reduction in muscle power (force x velocity). Although studies have shown that single muscle fiber force production and contractile velocity are reduced with age, no reported study has examined the molecular basis of the age-related decrements in single fiber muscle performance. We have developed protocols and technological platforms to apply sinusoidal analysis to human skeletal muscle fibers that allow examination of the effect of age on single muscle fiber kinetics and structure at the level of the myosin-actin cross-bridge. Our hypothesis is that aging reduces contractile function by depressing myosin kinetic parameters and reducing myosin protein content. We will test this hypothesis by examining single skeletal muscle fiber function of the thigh muscle (vastus lateralis) in young and elderly men and women. 2) Procedures involving human subjects: The following procedures will be performed during two (young) or three (elderly) out-patient visits to the University of Vermont General Clinical Research Center (GCRC) or Cardiac Rehabilitation Center: Muscle Strength Testing - The contractile performance of the knee extensor muscles will be tested under isometric and isokinetic conditions using a multi-joint dynamometer. Exercise Stress Test - Aerobic exercise capacity will be measured during treadmill exercise. Body Composition Analysis - Whole body fat and fat-free tissue mass will be measured by dual energy x-ray absorptiometry to determine whole body lean tissue mass and appendicular muscle mass. Thigh muscle cross-sectional area will be measured by computed tomography. Electrocardiogram - Resting ECG will be performed to test for signs of heart disease and will be performed on the elderly during the exercise test to monitor cardiac function. Blood Samples - Blood samples will be taken to measure standard blood chemistry, counts (CBC w/diff), and liver/kidney/hormonal function and to determine clotting ability (PT/PTT) per the GCRC's requirement of any volunteer undergoing the muscle biopsy procedure. Muscle Tissue Collection - Percutaneous biopsies of the right and left thigh (vastus lateralis) will be performed under lidocaine anesthesia. The following procedures will be performed by volunteers outside of the GCRC: Questionnaires - A Medical Outcomes Short Form Questionnaire (MOS-SF-36) which measures 8 domains, including physical functioning, role functioning, bodily pain, general health, vitality, social functioning, mental health and reported health transition, will be completed. Activity monitor - A small accelerometer will be attached to the subject's waistband of their pants for 7 days to monitor activity level.
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{
"pile_set_name": "NIH ExPorter"
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Modern techniques for the management of recurrent cardiac arrhythmias are frequently based on the results of electrophysiology studies in a cardiac catheterization laboratory. Among the most important yet difficult and time consuming aspects of these studies are the observation and accurate measurement of the timing of intracardiac electrograms. Certain preliminary observation must be made during the procedure itself (online) while more detailed analysis is done later (offline) by working through the length strip chart recording with a pair of calipers and millimeter scale. The hypothesis of this proposal is that such analysis can be done more swiftly, accurately, and economically by using modern computer techniques for acquisition, measurement, display retrieval of intracardiac signals. The long term goal of this project is to develop a computerized system for cardiac electrophysiology studies. This will have hardware and software for: online measurement and display of electrogram timing; continuous digital storage of the signals and their timing; retrieval of sections of the record, during and after the study, with rapid display, additional analysis, and selected hard copy graphics. In Phase I we will demonstrate the feasibility of computer acquisition, interval analysis, display and storage of multichannel recordings from the electrophysiology laboratory. In Phase II we will design, develop, and construct a prototype system and perform clinical testing and evaluation at several centers.
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{
"pile_set_name": "NIH ExPorter"
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Califomia State University, Long Beach (CSULB) established an MBRS (Minority Biomedical Research Support) Support of Continuous Research Excellence (SCORE) program on its campus in the fall of 2001 with five Principal Investigators. We now propose to add an additional 13 faculty members as research investigators in a supplemental application to our parent grant - 1 S06 GM63119-01. By doing so, we will further meet our goals to increase the research capabilities of faculty members within the Departments of Chemistry & Biochemistry and Biological Sciences and to provide the infrastructure necessary to support highly productive and competitive research. Goal 1: Increase research skills and capabilities as well as productivity of participating faculty members so they will be more competitive for R01 or equivalent grants. Specific measurable objectives for the Pl's on the supplemental grant will include: 1) an increased publication rate - 50% will have at least one manuscript accepted for publication by the end of year 2 of the supplement; 100% will have at least one manuscript accepted by the end of year 3; and 2) at least 40% of the participating faculty members will write and submit R01 or equivalent applications during the period of the proposed grant; at least 40% of the Pl's will write applications as continuing Pl's on the next competitive SCORE grant application. Goal 2: Increase the institutional infrastructure to support and maintain research needs of faculty members at a higher level. A self study is underway to evaluate department, college, and university support and needs of Pl's and will provide the basis for recommendations to the University administration for ways to improve in key areas. Measurable outcomes will include an increased awareness of and commitment to support the needs of the faculty to develop and maintain competitive research programs. PI's in the supplemental application will be included in this on-going study. [unreadable] [unreadable] The proposed projects of the faculty investigators cover a wide range of biomedical research, both in basic and applied areas. Provided the needed time, resources, and institutional support to carry out research, participants will become more productive and competitive for mainstream grants. This will significantly strengthen biomedical research within the College of Natural Sciences and Mathematics, promote involvement of other faculty members at a higher level of research, and in line with NIH goals, provide expanded opportunities for underrepresented minorities in biomedical research. [unreadable] [unreadable]
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{
"pile_set_name": "NIH ExPorter"
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Increasing rates of acquired and transmitted HIV drug resistance threaten to cripple large-scale antiretroviral therapy (ART) rollout and undermine HIV treatment programs in resource-limited settings. Existing drug resistance genotyping approaches are costly and complex, and their use in low- and middle-income nations prior to two consecutive ART regimen failures is precluded on account of high costs and limited resources. A simple and inexpensive ART drug resistance monitoring option stands to improve the treatment paradigm in these areas, facilitating better clinical decision-making regarding ART treatment and resulting in improved patient outcomes, reduced HIV transmission rates, and healthcare system cost savings. To this end, Aldatu Biosciences has pioneered the development of Pan-Degenerate Amplification and Adaption (or PANDAA(tm)), a simple, low-cost, highly sensitive method for HIV drug resistance detection with multi-parameter superiority to currently available commercial genotyping options. PANDAA(tm) enables for the first time an already low-cost and sensitive genotyping technology, quantitative real-time PCR (qPCR), for HIV genotyping by overcoming previously insurmountable challenges associated with the biology of HIV. Specifically, PANDAA(tm) reagents compensate for secondary sequence variation in the HIV genome without sacrificing specificity, allowing rapid and sensitive detection of drug resistant variants. Feasibility studies performed at the Harvard School of Public Health have rigorously demonstrated that PANDAA(tm) 1) detects drug-resistant HIV variants with >99% sensitivity; 2) is HIV subtype-independent; 3) is multiplexed to simultaneously quantify resistance at multiple genomic positions; and 4) quantitative detection using a calibrator probe measures total HIV RNA and serves as a confirmatory viral load test. In this Phase II project, Aldatu will translate our validated lab-based assay into a clinical diagnostic product - PANDAA(tm) HIV6 - a thermostable, sample-in/answer-out kit that identifies six clinically actionable HIV mutations found in >95% of patients failing a WHO-recommended first-line regimen. This will facilitate Aldatu's long-term goal of radically improving HIV treatment program efficacy and cost- efficiency by empowering clinicians to make informed therapeutic decisions and assign the most effective ART regimens at the lowest achievable cost. Through the aims proposed here, we will 1) confirm that an optimized thermostable PANDAA(tm) HIV6 prototype can sensitively and specifically quantify drug resistance from HIV-1 infected whole blood, plasma, and dried blood spots using existing RNA extraction methods; 2) demonstrate that PANDAA(tm) HIV6 performance metrics fulfill established criteria for both in vitro HIV drug resistance genotyping and quantitative assays; and 3) verify that PANDAA(tm) HIV6 intended end-user, multi-site implementation is highly reproducible. Successful commercialization of PANDAA(tm) HIV6 will result in the first- time availability of an HIV genotyping option that is cos-effective to implement at first-line ART failure in low- and middle-income countries, creating an annual market of $120M USD for HIV drug resistance testing.
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{
"pile_set_name": "NIH ExPorter"
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Schizophrenia is an often devastating neuropsychiatric illness whose etiology remains unknown despite considerable study. Genetic factors have been strongly and consistently implicated in its etiology. Currently, there are multiple positive and plausible findings, but no finding currently meets a rigorous but appropriate definition of proof. There is considerable uncertainty about which of the findings in the literature represent true findings upon which to build the next generation of schizophrenia research. Our goals are extremely ambitious but attainable. We wish to help research into the genetics of schizophrenia move to a solid empirical foundation that can withstand rigorous scrutiny. We have designed a well-functioning international collaboration to attain these aims: (1) We have identified ~29,000 cases via record linkage who could be contacted immediately. (2) We seek to biobank DMA samples from 7,500 cases with schizophrenia and 7,500 well-matched controls ascertained via high-quality Swedish national hospitalization and population registries. Both cases and controls will be population-based and of Scandinavian ancestry. Neurocognitive endophenotypes will be collected. (3) We will rigorously evaluate 10 candidate genes for schizophrenia. (3a) Following a comprehensive quantitative literature review, a pluralistic expert panel will select the 10 most promising genes. (3b) Genotype all cases and controls for 768 SNPs in these genes to capture genetic variation comprehensively, analyze, and with the expert panel select two genes for resequencing entire genomic transcripts for both common variants (N=48 cases, Aim 3c) and functional genomic regions for rare variants (N=1000 cases, Aim 3d). (3e) Complete the evaluation of these genes by conducting additional genotyping in cases and controls for SNPs identified in re-sequencing and finalize the analyses by investigating the relevance of neurocognition, birth insults (GxE interactions), family history (covariate indexing genetic risk), and age 18 conscription data (males only, possible endophenotypes) using prospective register data. A full-scale pilot study has proven that we can achieve these aims and strongly supports the validity of our assumptions. We have improved our diagnostic procedures and have shown that power will not be substantially altered by misclassification of either cases or controls. This research team is committed to collaborative "open-source" genetic research. All phenotypes, genotypes, and DMA samples will be made available via the Kl BioBank. Application procedures will be straight-forward and require a brief page application that documents: a reasonable scientific plan, a timeline for completion and return of all unused samples, commitment to depositing all data created on these samples into a central repository at the Kl upon completion, and agreement to uphold the ethical and altruistic principles fundamental to this project. On the short-term, completion of this work will provide strong and possibly definitive evidence of the relevance of the best current set of 10 candidate genes for schizophrenia. For the long-term, establishment of this sample will provide an accessible resource for the psychiatric research community. Future projects could include whole genome association and nested case-control studies.
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{
"pile_set_name": "NIH ExPorter"
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The EGF receptor (EGFR) is overexpressed in many human tumors implicating it in the pathogenesis of some cancers. To study regulation of the EGFR gene, the promoter region was isolated and shown to contain many transcription factor binding sites. The expression of the EGF receptor (EGFR) gene is governed by the interaction with the GC-rich promoter region of the gene of transcription factors that activate (Spl and ETF) or repress (GCF) transcription. To examine the relationship between EGFR expression and GCF expression, we have analyzed the level of GCF RNA in human tissues and cancer cell lines. We have also examined the level of GCF RNA after treatment of cells with agents that regulate EGFR expression. Three RNA species hybridize to the GCF cDNA and fragments of the cDNA have been used to determine the relationship of these RNA species. The chromosomal localization of the GCF gene has been determined by in situ hybridization. The GCF cDNA has been placed under control of the metal inducible metallothionein promoter and three lines of transgenic mice have been generated that express GCF mRNA.
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{
"pile_set_name": "NIH ExPorter"
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All of our kinetic measurements rely upon access to the corresponding equilibrium behavior of the lipid/water systems under investigation. Thus, temperature-composition (T-C) phase diagram construction is an integral part of our time-resolved studies. A separate ongoing project, concerned with establishing the relationship between lipid molecular structure, overall sample composition and mesophase behavior, also requires T-C phase diagram construction. Much of the mesophase identification and structure characterization required for mapping out a phase diagram can be done using an in-house rotation anode. However, our phase diagrams extend up to 100 C and occasionally go as high as 140 C where time-dependent sample decomposition becomes becomes a major problem. To obviate this limitation, all such measurements at and above 50 C are now done using synchrotron radiation where exposure times are down by an order of magnitude compared to the rotating anode. For this purpose, we have specially built a temperature-regulated sample holder accommodating up to 7 samples at a time that is used in conjunction with a multiple-frame image plate detector. Most recently, the temperature-composition phase diagram of monovaccenin (a C18:1c11 monoacylglycerol) in water was constructed using small-and wide-angle x-ray scattering in the range of ca 0 C to 111 C and ca 0% to 60% (w/w) water in the hearting direction. The phase identified in the system include the lamellar crystalline (Lc) phase, the lamellar liquid crystalline (L) phase, the fluid isotropic (Fl) phase, two inverted cubic phases (Q230,la3d; Q224, Pn3m), and the inverted hexagonal (HII) phase. The monovaccenin/water phase diagram is remarkably similar to that of the monoolein (aC18:1c9 monoacylglycerol)/water system. A portion of the current T-C phase diagram for the monovaccenin system shows evidence of non-equilibrium behavior in the region below 60 C and above 20% (w/w) water that will require more detailed investigation.
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{
"pile_set_name": "NIH ExPorter"
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Abstract Description: In rheumatoid arthritis (RA), an inflammatory stimulus from secreted cytokines increases osteoclast activity, erodes bone surfaces, and progressively destroys joints. Research advances have identified the mechanism of osteoclastogenesis and bone resorption, and provided new medications to arrest disease progression. Despite this, there is little understanding of why eroded articular bone fails to heal. It is also unclear why patients with RA have systemic bone loss, currently attributed to increased osteoclastic bone resorption without evidence. We previously showed that tumor necrosis factor-1 (TNF), a major inflammatory mediator in arthritis, potently inhibits OB differentiation, suggesting that reduced OB activity abandons bone to unopposed osteoclastic resorption. In this proposal, we focus on the mechanism of reduced bone formation and healing in RA and hypothesize that TNF activates a key inhibitor of OB differentiation, the paired related homeodomain protein-1(Prx1). Prx1 potently suppresses OB differentiation and bone formation through inhibition of Osx and RUNX2 transcription. These factors are critical for the phenotypic commitment of pluripotent precursors to mature bone forming OB. We previously identified a TNF element in the Osx promoter that confers transcriptional inhibition. Activation of this inhibitory mechanism by TNF is signaled via MAPK. In preliminary studies, we utilized this TNF responsive DNA sequence as bait to identify Prx1 as the TNF-induced inhibitor of Osx transcription and confirmed Prx1 through mass spectroscopy and ChIP assay. RUNX2 transcription and mRNA can also be inhibited by Prx1. Prx1 is an embryonic limb bud enhancer active between E9.5 and E15. Our preliminary data will show that TNF reactivates Prx1 in adult bone and silencing of Prx1 completely abrogates TNF suppression of Osx and OB differentiation. Hypothesis: We hypothesize that Prx1 performs a pivotal function as a molecular signal of inflammatory suppression of bone healing and renewal. Aims / Methods: In this grant application we will evaluate the mechanism of Prx1 action and test our hypothesis in vivo using a skeletal-specific Prx1 knockout. Our hypothesis predicts that Prx1 deletion will confer resistance to TNF-induced bone loss in a murine model of rheumatoid arthritis. To test our hypothesis we propose three aims: Aim 1: To determine the mechanism of Prx1 action. 1A. Determine if Prx1 inhibition of Osx transcription requires MAPK and if Prx1 is phosphorylated. Specific inhibitors of MAPK will be used in cell culture. 1B. Determine the mechanism of action of Prx1on the Osx promoter: Determine if Prx1 interacts with RUNX2 at their continuous binding sites on the Osx promoter. Pull down experiments will be used to study protein-protein interaction. 1C. To determine if RUNX2 and/or Osx expression will abrogate Prx1 inhibition of OB differentiation. Expression vectors will be used in primary cell culture via lentivirus constructs to evaluate the effect of Osx or RUNX2 expression on Prx1 inhibition of OB differentiation. Aim 2: Determine if Prx1 is a mediator of TNF induced bone loss in vivo. 2A. Determine if OB-specific deletion of Prx1 increases baseline OB numbers and bone formation in adult animals. (Prx1 flox/flox X 2.3kb Cola1-Cre mice). Dynamic histomorphometry, microCT, histology, and bone density will be used. 2B. Determine if OB precursors cultured from Prx1 knockout mice are resistant to TNF inhibition of OB differentiation. Primary cell culture from marrow stromal cells will be used to test TNF responsiveness. Aim 3: Determine if Prx1 deletion ameliorates bone loss in TgTNF arthritic mice (Prxflox/flox, 2.3Cola1Cre X TgTNF). The effect of Prx knockout in bone on the extent of bone loss, erosions, and inflammation will be determined in the TNF expressing mouse. Techniques as in Aim 2A plus inflammation scores. Summary: This project will identify a novel pathway that prevents new bone formation, healing, and restoration of normal bone in inflammatory bone disorders, including RA, aging, and menopause. PUBLIC HEALTH RELEVANCE: Project narrative More than 4 billion healthcare dollars are spent in the U.S. each year on skeletal morbidity. In the inflammatory states of arthritis, aging, and hypogonadism, fractures are common and healing is impaired. Elevation of tumor necrosis factor (TNF) is a shared feature of these conditions. Research has found that TNF and other mediators increases bone resorption, and new medications have been developed that slow the destructive bone resorption process. However, these medications do not enhance healing and regeneration of bone for a return to normal. We identified a TNF-stimulated factor, Prx1, that interferes with the development of new bone forming cells and bone formation. This proposal will test the role of Prx1 as an inhibitor of bone renewal in inflammatory bone disorders and determine the mechanism of Prx1 action. Understanding this mechanism will allow us to find new medications that stimulate new bone formation and regeneration of tissue in veterans who suffer from arthritis, aging, and menopause associated fractures.
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Induced collagen expression by hepatic stellate cells (HSC) is the hallmark of alcoholic liver fibrosis. Our laboratory recently demonstrated the potential link between depletion of PPARgamma in HSC and liver fibrogenesis and the reversal of HSC activation with PPARgamma ligands. The trainee will test the hypothesis that PPARgamma inhibits alpha1(I) collagen promoter in HSC line and liver fibrosis. Specific aims include determination of the specificity of PPARgamma-mediated inhibition of the promoter and elucidation of the mechanisms underlying the effect. The former will be achieved by transient transfection assays with the promoter-reporter gene and expression vectors for the members of nuclear receptors including PPARgamma. The latter will address PPARgamma-mediated negative cross-coupling with DNA-binding proteins for the promoter via DNase foot printing and gel shift assays and inhibition of co-activator recruitment by this nuclear protein which will be assessed by GST-fusion protein pull down assays and coimmununoprecipitation. PPARgamma-mediated suppression of the promoter will further be tested in vivo using the transgenic mice expressing GFP driven by the collagen promoter and adenoviral-mediated PPARgamma overexpression targeted to HSC by alpha-smooth muscle actin promoter. A similar approach will be taken to finally test the efficacy of PPARgamma overexpression for CCI[4] liver fibrosis in mice. These experiments will define the molecular basis for inhibition of collagen gene expression by PPARgamma and will test the potential of this mode if intervention as a novel therapy for alcoholic liver fibrosis.
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{
"pile_set_name": "NIH ExPorter"
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The integration of diverse cellular signals is critical to the precise spatial and temporal coordination of virtually all biological processes. Among the widely used regulatory mechanisms to achieve signal integration and biological coordination is protein phosphorylation. We have been investigating the role of specific protein phosphorylation events in controlling cell morphology, adhesion, and migration- processes that are stringently regulated by the Rho GTPases. These studies have revealed a critical role for the p190 Rho GTPase activating proteins (GAPs;p190A and p190B) as signal integrators whose phosphorylation by various intracellular kinases appears to be critical to its role in a variety of cellular processes. Our broad objective is to develop a clear understanding of the regulation of Rho- mediated cellular processes by the RhoGAPs, and the focus of the studies proposed here is to address the role of p190 RhoGAP phosphorylation in the integration of upstream regulatory signals. The following Aims are proposed: 1) To establish the regulatory function of PKC-mediated phosphorylation of p190A RhoGAP. 2) To establish a role for phospho-regulation of p190A in polarized cell migration. 3) To determine the functional role of phosphorylation-regulated protein interactions with the p190 FF domains. 4) To establish the regulation of p190B RhoGAP in IGF-1 signaling in cell adhesion. These 4 Aims reflect a large body of preliminary data that points to these critical phosphorylation events in the role of the p190 GAPs in regulating a variety of cell biological and developmental processes. We have generated the vast majority of reagents required for this analysis, which is expected to reveal substantial new insights into the role of these GAPs as signal integrators or "coincidence sensors" that regulate Rho-dependent cellular processes, including cell migration. Cell migration is an important cellular activity in the context of human cancers, where its role in metastasis, the most lethal aspect of the tumorigenic process, has been clearly established. By identifying regulatory mechanisms that affect cell migration, it should eventually be possible to develop novel therapeutic strategies to prevent or manage cancer metastasis. PUBLIC HEALTH RELEVANCE: The proposed studies address a fundamental issue in the biology of all normal and cancer cells, namely how do the various intracellular proteins integrate a variety of extracellular stimuli to properly "instruct" the cell to respond appropriately? By enhancing our understanding of how cancer cells respond to their environment, we may be able to develop strategies to disrupt the processes in these cells that contribute to their malignant properties of accelerated growth and metastatic spread.
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{
"pile_set_name": "NIH ExPorter"
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The goal of this project is to develop a collection of components that can be added to standard power wheelchairs to convert them into smart wheelchairs. Wheelchairs equipped with the Smart Wheelchair System will be able to assist users in two distinct ways: as a mobility aid, the system will present users with an immediate opportunity for independent mobility, and as a training tool, the smart wheelchair will allow users to safely develop and refine the skills necessary to operate a power wheelchair without the need for technological assistance. During Phase I, a prototype of the system will be developed which will serve as a testbed for demonstrating technical feasibility of our approach to providing navigation assistance to wheelchair users. The prototype will be compatible with wheelchairs from four manufacturers and will make use of a variety of sensor modalities. The result of Phase I will be a demonstration that existing smart wheelchair technology is sufficiently advanced to produce a robust and functional product ready for use in the real world. PROPOSED COMMERCIAL APPLICATION: The product developed by the end of Phase II will be a collection of modular components that can be attached to standard power wheelchairs from different manufacturers to convert them into smart wheelchairs. The system will accommodate all traditional input methods, will offer two different forms of navigation assistance to the user and will be useful both as a mobility aid and a training tool.
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{
"pile_set_name": "NIH ExPorter"
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PROJECT SUMMARY/ABSTRACT The need to train the next generation of medical geneticists has never been more urgent. Our biggest challenge in Medicine is to handle the flood of genomic information associated with new methodologies such as next generation sequencing. The overwhelming power of these new technologies is transforming the traditional approach to medical diagnosis and functional investigations. This renewal training proposal will prepare the future generation to tackle a new reality in which: 1) genetic testing and technology evolves rapidly, 2) most clinical testing is done outside of the medical genetics clinic, either by other specialists or direct-to-consumer, 3) there is a growing understanding of the influence of genetics on a vast array of human disease, and 4) precision medicine will shape future patient care. Our UCLA Intercampus Medical Genetics Post-Doctoral Training Program utilizes the outstanding, diverse faculty and facilities of four campuses: UCLA School of Medicine, Harbor-UCLA Medical Center, Cedars-Sinai Medical Center and Children's Hospital of Orange County. The faculty of this program provides a wealth of research opportunities, varying from basic molecular biology, genomics, cell biology, stem cell research, biochemical genetics, cytogenetics, population genetics, to clinical genetics and dysmorphology. Our collaborative Faculty is organized around three thematic areas: Genomic Medicine, Phenotyping in the Genomic Era, and Treatment of Genetic Disease. We will provide our trainees with a broad knowledge of medical genetics and an intensive experience in genetic research over two years, so that they may enter the academic community as independent investigators and future field leaders. Major strengths of the training environment include a vibrant clinical genetics program with access to an ethnically varied population, state-of-the-art diagnostic laboratories in cytogenetics, biochemical genetics, and molecular genetics, including a clinical genomics center that produces exome sequencing, a wide variety of well-funded research laboratories, a longstanding training experience of faculty, a specific postdoctoral course in medical genetics, an experienced associate director for Diversity to increase the recruitment of underrepresented trainees and a deep institutional commitment. Moreover, we have expanded our faculty and recruitment pool to specialists outside of Medical Genetics, recognizing that most genetics will in fact be practiced and studied beyond the traditional boundaries of our field. While our program has a 30-year history of success, this renewal proposal is focused squarely on the future, and enthusiastically embraces the enormous changes that new discoveries will bring.
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{
"pile_set_name": "NIH ExPorter"
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The goal of this investigation is to study the mechanisms by which endogenous pyrogen acts upon the thermoregulatory centers of the brain to alter the level at which body temperature is regulated - fever. We are interested in the route by which pyrogen enters the brain and whether it acts on neural tissue to produce prostaglandin E. We further wish to ascertain whether PGE is an essential intermediary in the fever pathway and whether other protein dependent steps quantifying the alterations in PGE levels in cerebrospinal fluid under a variety of natural and pathophysiological conditions, and correlating them with the thermoregulatory responses of rabbits measured by partitional calorimetry, we hope to answer these questions. Several hypotheses are outlined in the proposal together with protocols and techniques to test their validity.
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{
"pile_set_name": "NIH ExPorter"
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Recent evidence suggests that enhancing antibodies (or "factors") are formed during a wide variety of immunological responses, including those occurring in cancer patients, during pregnancy, and in allograft acceptance. Little is known of the specificity or immunochemical nature of serum blocking factors found in these situations nor of conditions which favor their induction or termination. The objectives of the proposed research are: 1) to characterize the specificity and immunochemical nature of enhancing factors, 2) to determine whether serum blocking factors present in these allo-immune states are similar and 3) to study, in a mouse model, conditions favoring the development of such factors by exploring the effects of pregnancy, gestational hormones, the sources and maturity of the immunizing tissues, and the mode of presentation of the allo-antigens to the host. The objectives will be approached initially by absorption of human blocking plasmas obtained from multiparous women with platelets and leukocytes from their husbands and reexamining their abilities to block in mixed leukocyte culture. Further, attempts will be made to characterize blocking factors by ion-exchange, gel filtration and affinity chromatography of these plasmas and of supernatants from mixed leukocyte cultures conducted in medium supplemented with blocking plasmas. The effects of gestational hormones on the induction of enhancing antibodies will be examined by treating mice with various such hormones before and after immunization with lyophilized spleen cells and assaying for enhancing factors by abrogation of mixed leukocyte responses, avoidance of G-V-H in parental to F sub 1 hybrid immunocompetent cell transfers, and prolongation of survival of tumors syngeneic to the donors of the immunizing cells. Various fetal and adult tissues will be compared and the intravenous, intraperitoneal, intradermal, and intramuscular routes examined for their possible influences on the induction of blocking factors. Elucidation of the nature and specificity of these factors should hasten the application of enhancement of clinical organ and tissue transplantation. Moreover, with knowledge of conditions leading to the induction and persistence of blocking antibodies, it should be possible to select conditions which favor their termination in cancer.
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{
"pile_set_name": "NIH ExPorter"
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An estimated 600,000 African-Americans have chronic hepatitis C virus (HCV) infection, representing 22% of the total infected population in the U.S. Prior studies suggest African-Americans with chronic HCV infection have a lower rate of response to anti-viral therapy than non-Hispanic whites. The difference is, in part, related to the predominance of genotype 1 among African-Americans. Response rates appear to higher with combination interferon plus ribavirin than with interferon monotherapy. However, the studies to date have included very low numbers of African-American subjects (<5%), limiting the interpretation of response rates. In the proposed study, the rate of sustained virological response (viral clearance) to pegylated interferon plus ribavirin will be compared in 200 African Americans and 200 non-Hispanic whites. The clinical, biochemical, or virological factors which predict sustained virological response to anti-viral therapy and reduced inflammatory activity on liver histology will be determined and early viral kinetics will be examined as a predictor of response or non-response. This collaborative study involving eight clinical centers will also provide the clinical data and biological specimens to coinvestigators focused on determining the virological, cellular, immunological and genetic factors that underlie the response to antiviral therapy in hepatitis C. Pegylated interferon plus interferon is chosen as the anti-viral intervention because combination therapy has been shown to be superior to interferon monotherapy and preliminary data indicate pegylated interferons are superior to standard interferons. Additionally, the convenience of once weekly dosing may improve compliance. Participants will undergo liver biopsy prior to study entry and at end of follow-up (96 wks). Virological analyses include HCV RNA quantitation (qualitative and quantitative) and HCV genotyping. Baseline assessments include demographic (using self-reporting of race/ethnicity) risk factor assessment, biochemistry and hematology, quality-of-life and fatigue assessments. Follow-up visits will include adverse events inquiry, assessment of compliance, collection of serum and peripheral blood mononuclear cells for virological analyses, and repeat liver biopys 48 weeks after completion of treatment. All study visits, including liver biopsies, will occur in the General Clinical Research Center. The primary treatment outcome is loss of HCV RNA at 96 weeks (48 weeks post-treatment). Secondary endpoints include loss of HCV RNA at 48 weeks; normalization of liver enzymes and improvement in histological inflammatory indices at 96 weeks; and tolerability (assessed by? adverse event inquiry and fatigue questionnaires). This study will accurately define the sustained response rates with optimal anti-viral therapy in African-Americans and provide important insights into the factors underlying differences in response compared to non-Hispanic whites. Moreover, the methodologies developed for patient outreach within the context of this collaborative study will serve as a model for enhancing participation of African Americans in clinical research.
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{
"pile_set_name": "NIH ExPorter"
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The goal of the proposed project is to use antibodies recognizing portions of the human Blym oncogene translation product to facilitate its characterization. Synthetic peptides composed of amino acids from the predicted Blym amino acid sequence will be used as immunogens to generate rabbit heterosera and murine monoclonal antibodies reactive with both the peptides and the native Blym protein. Initial screening for anti-peptide reactivity will be accomplished using the enzyme linked immunoabsorbant assays (ELISA), and subsequent assessment of reactivity with the native protein will include immunoprecipitation, immunoblotting, fluorescence microscopy and fluorescence activated cell sorter analysis. Antibodies reactive with the Blym protein will be used to determine its subcellular location, cell cycle expression and association with other cellular proteins, and to evaluate quantitative and qualitative differences in protein expression in normal and neoplastic cells. These antibodies will also facilitate the characterization of Blym protein expression in leukemias and lymphomas of B and non-B cell origin and help define the protein's role in both normal cellular differentiation and lymphomagenesis.
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{
"pile_set_name": "NIH ExPorter"
}
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Mutations in the RNA-binding protein TDP-43 cause amyotrophic lateral sclerosis (ALS). Inclusions enriched in TDP-43 in the cytoplasm of spinal cord neurons in both familial and sporadic ALS are hallmarks of the disease. Two recent yeast genome-wide loss-of-function toxicity suppressor screens revealed the strongest suppressor of TDP-43-mediated toxicity is the ablation of the gene encoding the metallophosphoesterase (MPE) Dbr1, the only enzyme known to hydrolyze the 2',5'-phosphodiester bonds formed within introns during their excision from pre-mRNA by the spliceosome. Decreasing Dbr1 activity results in the accumulation of RNA lariats that are proposed to sequester pathogenic TDP-43, preventing it from interfering with normal RNA metabolism. Supporting this hypothesis, knockdown of debranching activity in yeast, a human neuronal cell line, and in primary rat neurons protects them from TDP-43-mediated toxicity. The high degree of sequence identity in the catalytic domains of Dbr1 proteins across all eukaryotic species supports the observation that Dbr1's influence on TDP-43 activity is similar from yeast to man. We recently determined the first crystal structures of an RNA lariat debranching enzyme alone and in complex with a synthetic RNA containing a bona fide branchpoint identical to those found in intron RNA lariats. Dbr1 from the eukaryotic organism Entamoeba histolytica (Eh) crystallized most readily, revealing several unexpected features of Dbr1 enzymes relative to other MPE family members. All Dbr1 enzymes are mononuclear, possessing an invariant active site cysteine residue in the position of the aspartic acid observed in all previously characterized MPE superfamily members, all of which are active as dinuclear enzymes. In addition, all Dbr1 proteins contain a highly conserved insertion loop not found in other MPEs we term the lariat recognition loop (LRL). Functional data coming from in vivo complementation assays using multiple Dbr1 variants expressed in trans in dbr1 yeast support the proposed mononuclear enzymatic mechanism, as well as the roles assigned to the various unique structural elements observed in the crystal structures. The structures also reveal the molecular basis for how Dbr1 distinguishes 22,52-phosphodiester linkages from the far more abundant 32,52-phosphodiester linkages. With these results in-hand, we are now in possession of the tools needed to test the hypothesis that inhibition of Dbr1 represents a novel therapeutic avenue to treat TDP-43-mediated ALS. These tools include: 1) large quantities of purified Dbr1 proteins from multiple species, including human; 2) a tested, robust in vitro RNA debranching assay amenable to high throughput screening (HTS) of small molecule libraries for inhibitors; 3) the ability to synthesize, in parallel with the HTS inhibitor search, branched RNA analogs through the introduction of sugar modifications and linkers in order to mimic the conformation of the branched RNA we observe bound to the enzyme crystallographically, which differs from the conformations of these species in solution; 4) an in vivo complementation assay to test the effectiveness of potential inhibitors coming from both of the pipelines mentioned above; 5) the ability to rapidly observe the atomic details of inhibitorDbr1 complexes to enable the rational design of compounds with greater affinity and specificity; 6) the ability to perform initial toxiciy screens of candidate Dbr1 inhibitor compounds using cultured human neurons; and 7) the ability to pursue the structure of human Dbr1. The completion of the work outlined in this proposal on the Dbr1 enzyme is required before testing inhibitors in cell-based and murine models of TDP-43 mediated toxicity in ALS can begin.
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{
"pile_set_name": "NIH ExPorter"
}
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The Neuropathology Core of the UC Davis Alzheimer's Disease Center (UCD ADC) has 3 major goals: (1) to obtain brain autopsies on ADC patients and controls, (2) to accurately diagnose all brain lesions encountered at autopsy in these individuals and transfer information about these diagnoses to the clinical core, and (3) to preserve and distribute autopsy brain tissues to research collaborators. This Core has developed a protocol in conjunction with the Clinical Core for recruitment of subjects to the brain donation program which relies upon ADC clinicians to approach patients or controls early on in the evaluation process. Once recruited, a number of methods have been developed for the distribution and tracking of signed autopsy consents and procedural information so that, at the time of death, the mechanism for activating the brain retrieval protocol is simple and straightforward. This protocol relies upon 24-hour a day on-call trained technicians who travel to the local mortuary (or other facility) to remove the brain. In most cases, half the brain is formalin fixed and the other half is coronally sectioned and frozen between dry ice. In special situations such as cerebrovascular disease, advance information is provided about lesion location so that the relevant area is formalin fixed. Provisions for very rapid brain removal and tissue processing are also made for some collaborators. Subsequent processing is performed in the Neuropathology Core Laboratory in Davis. Initially, 25 blocks of formalin fixed tissue will be obtained for paraffin embedment from multiple neocortical, limbic, diencephalic, basal ganglia, and brainstem regions. All sections will be stained with hematoxylin-eosin and a subgroup with Bielschowsky's sliver technique. Selected blocks will be stained with Luxol fast blue-cresyl violet to identify periventricular white matter degeneration, and with Congo red and beta amyloid immunostain to detect associated amyloid angiopathy. The blocks taken are compatible with those suggested by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). All tissue will be examined by a single neuropathologist, the Core PI, who will produce a standard gross and microscopic neuropathology report, and will quantitate neuritic plaques and neurofibrillary tangles. This method permits classification of all pathological diagnoses according to the suggested CERAD schema. Final reports are returned to the Clinical Core, where they are communicated to the patient's next of kin by ADC clinicians familiar with the case. Tissue and brain DNA is banked in the neuropathology laboratory. mRNA screening of frozen specimens will be used to assess the acceptability of tissue for molecular and biochemical studies. All data are logged into the Neuropathology Laboratory data base, which includes an inventory of all tissue, mode of processing and storage, pathological diagnosis, and autolysis interval. Quantitative data and final neuropathologic diagnoses according to CERAD criteria are recorded and entered into the centralized database, where it is readily linked to other data.
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{
"pile_set_name": "NIH ExPorter"
}
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The primary goal of this study is to conduct a comprehensive investigation of priapism in boys and young men with sickle cell disease (SCD). As such, it represents the initial step toward defining an effective way to manage priapism, and to reduce the frequency of impotence that is its major complication in adult males with SCD. The aims of this proposal are: 1) to conduct a Iongitudinal cohort study in order to define the incidence of priapism in relationship to the physical and hormonal developmental stages of puberty and early maturity, to explore the relationship between priapism and psychological adjustment; and 2) to conduct a pilot, placebo-controlled intervention trial in which the ability of pseudoephedrine to prevent priapism will be evaluated. The first stage of this proposal involves an observational study that will be open to all boys and young men with SCD between the ages of 7 -29 years. They will keep daily records of the occurrence of priapism, and will be admitted every 6 months for an intensive evaluation of physical growth, genital pubertal stage, body composition, bone age, gonadotropins, testosterone, insulin-like growth factor and nocturnal penile tumescence. During these admissions, the participants will also complete several psychological assessments. Data from this phase will be used to identify the association (if any) between priapism and pubertal stage, gonadotropin levels, and testosterone concentration. The data will also determine if there is a relationship between priapism and psychological adjustment. The second stage of this proposal will seek to enroll those individuals who are found to have qualifying episodes of priapism on to a randomized, double-blinded, placebo-controlled clinical trial of pseudoephedrine. The purpose of this pilot study is to determine whether pseudoephedrine is able to prevent episodes of priapism. During this trial, each participant will continue to keep the same daily journal. In addition, each participant will be admitted at the beginning and end of the trial to complete the same physical, hormonal and psychological assessments as were performed in the observational phase. The outcome measures of the prevention trial will be the occurrence of priapism, duration of priapism and the interval between episodes of priapism. In addition, physical growth, secondary sexual development, body composition and psychological adjustment will be compared between the treatment arms. The data collected will establish the feasibility of certain key methods, and will provide estimates of rates, standard deviations, median time-to-event. These results, which are absolutely essential before a large scale treatment trial can be planned, will provide the biological and statistical background for future work in this field.
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{
"pile_set_name": "NIH ExPorter"
}
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Support is requested for participation in the cooperative clinical trials of the southeastern Cancer Study Group. Phase I studies of new schedules of dosage or new combinations of drugs or new combined modalities. The Group will not engage as a Group in initial toxicity studies of new agents. Phase II studies which may or may not be randomized of the effectiveness of a specific treatment plan in a series of patients with a specific disease or diseases. When appropriate, these studies will be disease-oriented, especially in the signal tumor but we also intend to include broadspectrum studies of promising agents or combination. Phase III studies are randomized comparisons (double- blind, if feasible) of two or more treatment plans. The specific expertise of the Group in the past has been in hematologic malignancies. Emphasis has steadily shifted toward solid tumors which now account for a large and increasing proportion of our case accessions. A Radiation Therapy Committee has been formed, radiotherapists have been accepted as members and we expect combined modality approaches to increase. Immunotherapy protocols have been instituted and will be expanded as justified by increasing knowledge. Ancillary and pilot studies at one or more institutions are encouraged: 1) Preliminary studies which may lead to data justifying a Group study; 2) Basic investigations directed toward elucidating mechanisms of action or other aspects of treatment given in a Group protocol; 3) Studies directed at better methods of evaluation of results; 4) Studies to improve supportive care. Emphasis is placed upon thorough planning, careful review of data and statistically sound evaluation of results. Important secondary benefits of these studies are the excellence of patient care and improved training of house officers and medical students.
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{
"pile_set_name": "NIH ExPorter"
}
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V(D)J recombination constructs the variable regions of immunoglobulin and T cell receptor genes in developing lymphocytes through assembly of component gene fragments. The array of possible combinations for gene assembly is the primary basis for sequence diversity of the antigen binding receptor molecules in the immune system. Aberrant recombination reactions, such as those resulting in chromosomal translocations, can lead to lymphoid malignancies. In addition, reduced V(D)J recombination activity, as a result of point mutations in one or the other RAG protein, can lead to immunodeficiency diseases. To understand the molecular basis for these diseases, the factors that catalyze the V(D)J recombination reaction need to be better characterized. The initial site-specific DNA cleavage reaction is catalyzed by the V(D)J recombinase consisting of RAG1 and RAG2, proteins encoded by the recombination-activating genes. Together the RAG proteins bind to a conserved recombination signal sequence (RSS), which borders each gene fragment, and catalyzes double-stranded cleavage between the RSS and the bordering gene fragment in a two-step mechanism. The joining steps, resulting in assembly of the gene fragments, require additional ubiquitous factors including proteins that function in double-stranded DNA break repair. The broad objective of this proposal is to characterize the macromolecular assembly of the RAG proteins with the RSS. In our recent studies, we have identified structural domains of RAG1 that each either interacts with RAG2, the RSS, or the coding gene segments. Based on our results, we have developed a model for participation of the RAG1 DNA-binding domains at each step of the V(D)J recombination reaction. To test our model, we will further characterize the DNA-binding domains in RAG1, and determine their importance at each catalytic step in the recombination reaction. In addition, we will investigate potential regulatory roles for RAG2 in facilitating the association of RAG1 with the RSS. Finally, the requirement for participation of each RAG1 domain in the formation of the catalytically-active complex, as well as in DNA cleavage activity, will be tested. Results from these studies will provide a valuable framework in the determination of the assembly and mechanism of the V(D)J recombinase.
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{
"pile_set_name": "NIH ExPorter"
}
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This project seeks to identify a central factor driving aging in order to develop targeted interventions to delay the onset or even reverse aging-related pathologies. My preliminary data demonstrate caloric restriction (CR), a proven intervention for increasing lifespan stimulates endogenous production of hydrogen sulfide gas and this is necessary for the stress resistance benefits of CR. Here, we test age related decline of endogenous hydrogen sulfide production and if it is delayed by a specific and more clinically favorable form of dietary restriction, methionine restriction, as a means to increase metabolic fitness, stress resistance and longevity.
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{
"pile_set_name": "NIH ExPorter"
}
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Relapse to cocaine use is a major barrier to successful treatment outcome. This research proposes to inititate a program of research for a new investigator interested in preventing relapse in homeless persons with cocaine use (primarily crack cocaine) disorders. It proposes to use ecological momentary assessment techniques (repeated surveying of subjects by cellular phone) to acquire real-time and near real time information about daily events in treatment participants' lives related to relapse and near-relapse events. The first aim is to develop a survey for use with a cellular phone assessment of lapse and relapse (the CALLER intrument) by adapting existing smoking relapse surveys used for real time assessment by Shiffman and colleagues. The second aim is to pilot test a computerized momentary assessment procedure by administering it via cellular telephone, to day treatment program particpants with a DSM IV Axis I cocaine use disorder. Participant feedback will be utilized to create a second generation survey for reliability and validity testing. The third aim will assess the reliability of the CALLER instrument using test-retest methodology. The fourth aim will be to assess the validity of the CALLER instrument by comparing relapse and relapse risk data to urine drug toxicology results, a standard retrospective "time-line follow-back" instrument, and an established cocaine relapse instrument, the Cocaine Relapse Interview (McCay et al, 1996). This study will demonstrate whether ecological momentary assessment is feasible with crack cocaine users, and add to the available existing methods to study relapse to cocaine use. This research will test for crack cocaine users, the assumptions of Marlatt and Gordon's theory that failure to cope in high risk situations results in relapse and that attributions regarding lapses lead to relapse (1985). Knowledge derived from development and testing of the innovative assessment methodology could contribute to long-term improved treatment outcome.
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{
"pile_set_name": "NIH ExPorter"
}
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The purpose of this project is development of biostatistical methods and mathematical models appropriate for the analysis of epidemiologic and experimental studies related to cancer control and prevention. Many of the statistical problems being studied under this project are derived from the consultation activities of the Section. The proper time metric to be used when applying Cox regression techniques to analyze a cohort's cancer incidence over time is being studied by simulation methods. Data are being generated according to known cancer age-specific incidence and known mortality from all causes. The time metrics being studied are follow-up time from study initiation and age at risk. Different study durations are also being evaluated. In addition, different methods to properly estimate the effect of risk factors which are related to age at ascertainment are being evaluated. The assumption of "proportional hazards" is commonly made when analyzing survival in patients treated for cancer. The scale parameter in parametric models and the underlying hazard function in semi-parametric models are assumed to vary between patients only because of the risk factors included in the model. However, extraneous hazard rate heterogeneity can produce substantial deviations from this assumption. This research will fit a Gamma-mixture of Weibull models to estimate the degree of heterogeneity and its biasing effect on estimated parameters and on the hazard ratio. Methodology is being developed to calculate the necessary sample size n,m (n is the number of measuring devices and m is the number of items being measured) to test the hypothesis that the accuracy of a measuring device is acceptably large. The results will be used to develop sampling methods to evaluate the accuracy of the CIS.
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{
"pile_set_name": "NIH ExPorter"
}
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This project is to determine if synaptic adhesive proteins (SAPs), neuroligins and neurexins mediate the antidepressive effects of sleep-deprivation (SD) and drug treatments. Although some antidepressant drugs are effective treatments for depressive disorders, the efficacy of these treatments remains to be improved. Currently only one-third of patients with acute pure major depression achieve remission after the first-line antidepressant monotherapy. Up to two-thirds of patients with major depression do not respond to the first medication. More importantly, the beneficial effect of antidepressants usually does not occur within the few weeks of the treatment. This makes the treatment less tolerated during the first few weeks, and many patients discontinue treatment. However, SD improves mood immediately according to cumulative evidence in last 30 years of research without knowing the mechanisms and the difference for the effect between SD and antidepressant treatment. We hypothesize that restoration of normal prefrontal cortical synaptic excitability and the balance between neuroligins and neurexins plays a critical role in the reversal of depression symptoms by SD, orexins and SSRI treatment. We further hypothesize that the suppression of neuroligin 1 expression may eliminate the immediate antidepressive effect of SD and orexins and the antidepressive effect by chronic SSRI treatment. This proposed project will conduct studies in three specific aims. Aim 1 will determine the differential expression of SAPs in rodent models of depression. We have found that neuroligins and neurexins are altered differently in a rat model of depression induced by neonatal exposure to clomipramine. To further define the potential impact of SAPs in the pathology of depression and the regulation of antidepressive effects, we propose to examine SAPs in a rat model and mouse model of depression with different genetic background. Aim 2 will compare the alterations of SAPs in a rat model of depression among treatments with SD, orexins and fluoxetine. We will first compare the short-term effects of SD by gentle handling to that of SD by orexin and the acute effect of fluoxetine. Secondly, we will compare effects of long-term treatment with fluoxetine vs. orexin on behavior and SAPs. We will determine if SAPs, especially, neuroligins and neurexins are differentially regulated in depression models. Aim 3 will determine the effect of neuroligin 1 siRNA on SD, orexins and fluoxetine induced antidepressive effects. We will utilize neuroligin-1 siRNA to alter the expression of neuroligin 1 in the prefrontal cortex and to measure depressive behaviors and biomarkers of depressive pathology in the pre-frontal cortex in mice regarding the effects of manual SD and SD induced by orexins and fluoxetine treatment.
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{
"pile_set_name": "NIH ExPorter"
}
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The overall goal of this proposal is to test systematically complementary hypotheses about the physiological function of decreased conductance depolarizing potentials in the nervous system. One hypothesis is that decreased conductance depolarizing potentials (DCDPs) are used as a general integrative and modulatory mechanism to enhance and integrate related behavioral actions by coordinately increasing the excitability and synaptic efficacy of sensory, motor, and interneuronal elements in neural circuits underlying synergistic responses. A related hypothesis is that DCDPs, through their effects on major cellular regulators such as cyclic nucleotides and Ca++, play an important role in the generation of long-lasting neuronal modifications underlying associative and nonassociative learning. These hypotheses will be tested by examining the cellular changes accompanying the elicitation and modulation of a coordinated ensemble of defensive responses in the mollusc Aplysia by stimulation of its tail. Each response - tail withdrawal, gill withdrawal, inking, opaline release, and respiratory pumping - involves circuits in which major sensory, motor, and interneurons have been identified. Using electrophysiological and pharmacological techniques we will determine the loci in the circuits where DCDPs operate, the conditions under which they are triggered, and the contribution they make to the functional properties of the cells. In selected cells (the tail sensory neurons and ink motoneurons) presenting perticular advantages for detailed analysis, we will use voltage clamp, computer simulation, and biochemical techniques to examine the biophysical and biochemical mechanisms by which the DCDPs are produced and, in addition, systematically analyze the mechanisms by which DCDPa can be altered by paired spike activity in the cell and thus contribute to associative modifications that may play a role in learning. These analyses may lead not only to a greater understanding of the cellular mechanisms underlying neural integration, arousal and learning but may also lead to a refinement of techniques which may then be more readily applied to the analysis of behavioral control, modifiability and abnormalities in more complex organisms, including man.
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{
"pile_set_name": "NIH ExPorter"
}
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Mammalian skin and its appendages function as the outermost barrier of the body to protect inner organs from environmental hazards and keep essential fluids within the body. During embryonic development, a single layer of epidermal skin stem cells gives rise to the epidermis, hair follicles (HF) and the sebaceous gland, a process orchestrated by an array of regulatory pathways. In adult, homeostasis of each of three skin lineages is maintained long-term through self-renewal and differentiation of distinct skin stem cells. Through extensive investigation, much has been learned about the regulatory networks that control skin morphogenesis during embryonic development and self-renewal and differentiation of adult skin stem/progenitor cells. Recently, however, a novel layer of regulation mediated by miRNAs has been implicated in animal development. MiRNAs are a family of non-coding, small RNAs (~19-24nt) expressed in a wide range of animals and plants. Mature miRNAs act by specifically coupling with their target mRNAs at the 3' untranslated region to regulate the translation and/or mRNA stability. It is estimated that more than one third of protein-encoding mRNAs are regulated by miRNAs. In turn, miRNA-mediated regulation is believed to have a widespread impact on both protein output of transcriptome and evolution of gene regulatory networks. MiRNAs' potentials in globally regulating gene expression and developmental transitions during mammalian skin morphogenesis as well as their potential involvement in human skin diseases have attracted significant interests in the role of these novel regulators in skin biology. This proposal is based on my earlier findings and built to address three outstanding questions of miRNA biology and skin biology by focusing on miR-203, the most abundantly and specifically expressed miRNA in mammalian skin. In aim 1, I will dissect the underlying mechanisms of miR-203's functions by addressing an important question, that is, how each miRNA target contributes to the miRNA's functions in cell cycle regulation. In aim 2, I will investigate how the regulation of miR-203 itself is achieved in the skin by exploring its transcriptional regulation. In aim 3, I will begin to investigate miR-203's in vivo functions by examining its physiological functions during the earliest basal-suprabasal transition around E14 with a constitutive knockout mouse model. Taken together, studies proposed here, if successful, will significantly enhance our knowledge about individual miRNA's expression, function and regulation in the skin. The knowledge gained from these studies under normal development condition will also pave the way to investigate miRNA's roles in human diseases e.g. skin cancers where regulatory networks go awry. PUBLIC HEALTH RELEVANCE: MiRNA is a class of newly discovered regulatory genes. Recent studies have clearly demonstrated its critical functions in mammalian development and disease progression. In this proposal, I will investigate their functions in mammalian skin development. Knowledge gained in this research will lay a foundation to examine their functions in human skin diseases.
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{
"pile_set_name": "NIH ExPorter"
}
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Mitochondria comprise approximately 30% of the total intracellular volume of a mammalian cardiomyocyte. Not surprisingly, subtle alterations in mitochondrial function or membrane potential can have a dramatic influence on cardiomyocyte energy production and ultimately, the life or death individual cell. Indeed, cellular injury or stress stimulation directly elicit alterations in mitochondrial architecture, membrane potential, and oxidative capacity, which can be associated with ah irreversible loss of mitochondrial matrix contents and integral membrane protein constituents such as cytochrome C oxidase, followed soon thereafter by activation of intracellular proteases and DNA fragmentation enzymes associated with apoptosis and necrosis. An emerging paradigm places mitochondrial permeability transition pore (MPTP) formation as a central event precipitating cardiac myocyte apoptosis or necrosis following ischemic injury and during progressive heart failure. This project will test the hypothesis that MPTP is a primary mechanism responsible for driving myocardial cell death following ischemia- reperfusion injury or in response to long-standing cardiomyopathy. Both gain- and loss-of-function approaches will be implemented in the mouse as a means of dissecting the molecular determinants of MPTP and potential therapeutic opportunities. Specific aim 1 will define the mechanism of MPTP formation and its functional consequence in regulating cardiac myocyte apoptosis. Specific aim 2 will determine if inducible MPTP formation regulates cardiac myocyte apoptosis in vivo, while Specific aim 3 will target VDAC1/3 and cyclophilin D as a means of blocking MPTP formation in the heart. Even though inhibition of MPTP formation with pharmacologic agents often prevents cell death following catastrophic stimuli in diverse cell-types, the necessity of MPTP formation in mediating cardiomyocyte cell death following ischemic injury or long-standing cardiomyopathy has not been elucidated. Moreover, the identity and key functions of the putative MPTP components have not been subjected to genetic gain- or loss-of-function analysis in vivo, leaving the true identity of the complex unresolved. A greater understanding of the key constituents that comprise the MPTP, as well as further characterizing its functional dominance in the heart, will likely suggest novel approaches for treating human heart disease associated with cell death. [unreadable] [unreadable] [unreadable]
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{
"pile_set_name": "NIH ExPorter"
}
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The physiological effects of cyclic AMP in mammalian tissues are thought to be mediated by the action of cyclic AMP-dependent protein kinases. Mechanistic studies are being carried out in our laboratory on bovine cardiac muscle protein kinase, a cyclic AMP-activated enzyme which catalyzes phosphate transfer from ATP to peptide and protein substrates. In most of our work we have used the peptide substrate Leu-Arg-Arg-Ala-Ser-Leu-Gly and related peptides in which the residues on either side of the Ser residue have been replaced by other amino acids. Our current studies include an investigation of the identity of the inhibitory metal ion binding site on the catalytic subunit, the determination of the timing of the transfer of the metal ion-nucleotide complex from the gamma-phosphoryl group to the alpha-phosphoryl moiety, the characterization of important nucleophilic groups in the active site, and establishment of the stereochemistry of the binding of cyclic AMP to the regulatory subunit. Our research should provide much useful information about the interaction of cyclic AMP with isolated enzymes.
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{
"pile_set_name": "NIH ExPorter"
}
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The broad goal of this application is to characterize pathways of secretory trafficking in African trypanosomes using endogenous surface proteins (VSG and procyclin) as reporters. Trypanosomes cause disease in humans and livestock, and they avoid host immune responses by changing the expression of VSGs, the major glycosylphosphatidyl-inositol (GPI) anchored antigens of the bloodstream stage. Thus, proper trafficking of essential coat proteins, such as VSG, is critical to the success of the parasite. The interrelated Aims of this application all stem from observations made in the current funding period. First, trafficking of VSG and other reporters is critically dependent on GPI anchors, leading us to propose the GPI Valence Hypothesis: number of GPI anchors regulates progression and fate in the secretory pathway. Second, surface coat exchange (release of VSG and expression of procyclin) during differentiation involves both proteolysis and GPl hydrolysis of the old VSG coat. Proteolysis is mediated by a novel surface metalloprotease, and GPI hydrolysis unexpectedly involves surface expression of endogenous cytoplasmic GPI-PLC. Aim #1 will test the 'GPI Valence Hypothesis', that GPI valence controls progression, destination, and ultimately stability of membrane proteins within the secretory pathway of bloodstream stage parasites. Aim #2 will assess the role of membrane lipid rafts as the underlying mechanism of the Valence Hypothesis. Aim #3 will biochemically identify the metalloprotease (possibly a member of the newly identified MSP gene family), and will investigate the mechanism (thioacylation?) regulating surface expression of cytoplasmic GPI-PLC. Overall, these studies will illuminate essential secretory processes in trypanosomes and the role they play in the pathogenesis of trypanosomiasis.
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{
"pile_set_name": "NIH ExPorter"
}
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The genetics of life threatening diseases offer the possibility of fundamental insights into pathophysiology that can transform diagnosis and management. Genome wide genetic association studies (GWASs) of the past decade have identified DNA sequence genotypic relationships to disease phenotypes, usually without any accompanying insight into the incredibly complex biology that operates between genotype and disease risk. Our DVA Merit Award work has focused on the genetics of Systemic Lupus Erythematosus (SLE). There are now >50 established and published genetic associations and our recent results will raise this to >100 SLE risk loci. Associations without mechanisms are of very limited practical utility. Our present focus has become elucidating these mechanisms and we have made much progress at the IRF5 and ETS1 lupus risk loci. Using frequentist and Bayesian statistics along with the differences and similarities of the associated variants in the major human ancestries we generate Ancestry Informed Credible Sets (AICSs) of plausibly causal variants. The subsequent search for allele specific functional consequences for these variants is enormously aided by all of the work now underway characterizing the protein and RNA species that interact with chromatin. Using the dataset infrastructure now available and methods that identify DNA ligands, we have identified ZBTB3 and STAT1 as relatively specific AICS risk allele transcription factors for IRF5 and ETS1, respectively. We propose to focus on the important association in the STAT4 gene with SLE where STAT1, this time through its expression, again appears to be important. We have reduced the plausibly causal variants from 56 to only 4 variants in the 2nd and 4th introns of STAT4. We have results suggesting the astonishing possibility that HMGA1 binds with varying allele specificity to 3 of the 4 variants in the AICS for the STAT4 locus. HMGA1 acts as a chromatin scaffold influencing DNA looping and chromatin conformation. We (and others) have shown that STAT4 expression is altered by the risk haplotype. We have recent data showing that STAT1 expression is also associated with STAT4 alleles. In addition, we show association of the DNA binding sites of STAT1 with the 53 published SLE risk loci (p?10-10). With the strong association at STAT4 with SLE across all human ancestries (1.2<odds ratio (OR)<1.8), the STAT4 allele dependent expression of STAT4 and STAT1, the demonstration of allele specific binding of STAT1 at ETS1, the relationship of STAT1 to SLE risk loci, and the association of STAT4 with other inflammatory diseases (rheumatoid arthritis (RA), Sjgren's syndrome (SS), primary biliary cirrhosis (PBC), progressive systemic sclerosis (PSS), and type 1 diabetes (T1D)), we conclude that the STAT1-STAT4 locus has earned our concentrated effort. We will experimentally evaluate the relationship between the AICS variants (Aim 1) and STAT4 and STAT1 expression in the context of HMGA1 binding to the AICS, especially using luciferase expression vectors and with chromatin editing of the AICS variants. In addition, we will use chromatin editing strategies (CRISPR technologies) to establish the influence of allelic differences at the 4 plausibly causal variants on the expression of STAT1 and STAT4. We will identify the allele specific binding of STAT1 and STAT4 at SLE loci (Aim 2) using a standard protocol for chromatin immunoprecipitation followed by sequencing (ChIP-seq). Experiments will be performed in transformed B cell lines and in isolated B cells, both from patients and controls. These experiments will set the stage for future experiments in other cell types (various T cells, monocytes, dendritic cells) and for the exploration of mechanism in the other STAT1-STAT4 associated diseases: RA, SS, PBC, PSS, and T1D, emphasizing how important understanding the mechanism(s) will be for understanding human autoimmunity. This project will help illuminate the inside of a black box now existent between DNA variants in STAT4 and SLE disease expression and in the process provide insights, data, and new tools that have the potential to influence management and the development of therapeutics.
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{
"pile_set_name": "NIH ExPorter"
}
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Adipose tissue macrophages (ATMs) are a key component of the adipose tissue stromal cell population. With obesity, ATMs increase in number in visceral fat and also undergo qualitative changes in their inflammatory activity. ATMs in lean mice are comprised of Type 2 ATMs with low inflammatory capacity that express IL-10, an anti-inflammatory cytokine. With diet-induced obesity, the populations shifts to one where Type 1 ATMs predominates, a distinct ATM type with high inflammatory gene expression. The balance between these ATM subtypes is important since macrophage-mediated inflammation has been shown to be required for the develop insulin resistance in obesity. The goal of the PI's K08 award is to examine how the balance between Type 1 and Type 2 ATMs influences adipose tissue and metabolism via IL-10. During these studies, we developed novel techniques that allowed us to distinguish and study the two ATM types. Work during the award showed that Type 1 and Type 2 ATMs are generated by distinct recruitment pathways from circulating monocytes. In our studies, we discovered that Type 2 resident ATMs express both IL-10 and MGL1 (macrophage galactose-type c-type lectin 1) and Type 1 ATMs do not. In preliminary experiments, we examined MGL1 deficient mice and made the surprising finding that they are protected from glucose intolerance and insulin resistance with diet induced obesity. This protection is related to the fact that MGL1 is expressed on inflammatory 7/4hi monocytes in the blood and that these monocytes are decreased in obese Mgl1-/- mice compared to controls. These observations identify MGL1 as a novel receptor that regulates the levels of inflammatory monocytes similar to CCR2 and CX3CR1. The goal of this proposal is to delineate how MGL1 regulates monocyte function in obesity and how this influences the balance between Type 1 and Type 2 ATMs. We will elucidate how MGL1 functions in monocytes by addressing two primary aims: (1) To assess how MGL1 regulates monocyte stability and retention in the circulation. We will utilize adoptive transfer of monocytes from wild type and Mgl1-/- mice into lean and obese recipients to address the hypothesis that MGL1 is required for the maintenance of inflammatory monocytes in the blood. In vitro models of monocyte-endothelial cells adhesion will evaluate MGL1 mediated cell-cell interactions. (2) To identify MGL1 ligands in visceral adipose tissue in obesity. We will use affinity purification approaches to identify MGL1 ligands in adipose tissue using MGL1 fusion proteins. Overall, this proposal will expand upon a new research direction that has extended from the PI's K08 award. Funds from the R03 will support the independence of the PI as he builds his research program. Data generated from these studies will set the stage for a more expansive grant application. PUBLIC HEALTH RELEVANCE: Inflammatory changes in obesity have important consequences on the development of insulin resistance and diabetes. Many of these inflammatory changes relate to the activation of macrophages and monocytes, inflammatory cells that help direct immune responses. This proposal seeks to expand our understanding of a novel molecule that directs the activation of these monocytes with obesity. Results of this study could potentially lead to novel therapies for type 2 diabetes that are directed towards blocking obesity-induced inflammation.
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{
"pile_set_name": "NIH ExPorter"
}
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Dry eye conditions afflict an ever-growing segment of society, are associated with increased ocular morbidity and result in considerable medical expense. The most common cause of dry eye conditions is insufficient aqueous tear production by the lacrimal glands. In several instances (e.g., Sjogren's syndrome), the underlying cause of lacrimal gland hypofunction is unknown, but is associated with the presence of focal lymphocytic infiltrates which are surrounded by substantial, otherwise normal appearing secretory epithelial (acinar) cells. This observation points to the poorly understood role of the immune system in the regulation of lacrimal gland physiology in general, and aqueous tear production in particular, as a necessary and potentially productive new area of research. The long-term objectives of this research plan are to further our understanding concerning the regulation of aqueous tear production by the lacrimal glands. Specifically, the regulation of ion transport processes will be investigated with regard to their role in the development and/or progression of lacrimal gland hypofunction. This proposal tests the hypothesis that the immune system contributes to the regulation of fluid secretion by the lacrimal glands by affecting the activity or expression of ion transporters. The specific aims of this research proposal are to: l. Investigate the rapid regulation of ion transport by neural and immune factors that are present in lacrimal gland tissue in normal and disease states. In addition, determine the specific second messenger systems that translate binding of regulatory agents into changes in ion transport, and ultimately fluid secretion, by lacrimal acinar cells. 2. Examine the activity and molecular expression of ion transporters in response to chronic exposure of cultured lacrimal acinar cells to immune agents. Since dry eye conditions affect women much more frequently than men, studies will be performed with tissue obtained from female animals. However, this investigation will go beyond any performed to date using either male or female-derived lacrimal tissue. Thus, while studies will be performed using tissue derived from females, information gathered will be relevant to the regulation of lacrimal fluid secretion of either gender. The primary methods used to achieve these objectives incorporate pH- and Ca2+- sensitive fluorescent probes, electron microscopy, and Northern analysis using freshly prepared, or primary cultures of, lacrimal gland acinar cells.
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{
"pile_set_name": "NIH ExPorter"
}
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ABSTRACT One of the most prominent consequences of aging is the decline of immune function. Quite often, elderly individuals do not respond efficiently to novel or previously encountered antigens. This is exemplified by increased vulnerability of individuals 70 years of age and older to influenza and other infectious pathogens. The situation is exacerbated further by their refractory to protective vaccination. Thanks to the advances of modern medicine, life expectancy in developed countries has increased dramatically in the past century. Developing therapeutics to rejuvenate aged immune system will not only have tremendous impact on the quality of living of the fast growing aged population, but also help to stop the explosion of the age-related medical cost. Thymus involution, a condition manifested as progressive regression in thymic size and cellularity, is the one of the leading causes for age-associated immune dysfunction. While numerous efforts have been made to modulate/rejuvenate thymic function, manipulating the thymus, either in vitro or in vivo, proves to be difficult. The major challenge is to reproduce its unique extracellular matrix microenvironment that is critical for the survival and function of thymic epithelial cells (TECs), the predominant population within thymic stroma that are critical for both the success of T-cell development and maintaining the integrity of the thymus microenvironment. TECs cultured in traditional 2-D culture rapidly lose their molecular properties and fail to thrive. The preclinical research proposal proposes an innovative approach to rejuvenate the aged thymus. The project will take advantage of a novel thymus bioengineering technique, with which functional thymus organoids can be constructed de novo with isolated TECs. When transplanted into athymic mice, the bioengineered thymus organoids can support the development of a diverse, self-tolerant T-cell population in the hosts. The primary goal of the proposed project is to demonstrate the proof-of-concept that bioengineered thymus organoids constructed with TECs of younger donors can effectively rejuvenate adaptive immunity in aged mice (Aim 1). One foreseeable obstacle of the thymus bioengineering approach is the scarcity of TECs due to the rapid contraction of the postnatal TEC compartment, which occurs as early as 4-weeks after birth in mouse and 1 year in human. The proposal will explore the possibility of using human embryonic stem cells (hESCs) as an alternative source of TECs for therapeutics. The microenvironment of the bioengineered thymus scaffolds can provide both the extracellular matrix support and the signaling cues that might induce the differentiation of hESCs to TECs. Aim 2 of the proposal will demonstrate that the bioengineered thymus organoids constructed from TECs derived from hESCs can rejuvenate the adaptive immune system in aged mice. The long-term goal of the research project is to translate the thymus bioengineering technique to rejuvenate adaptive immunity in elders and to treat age-related immune dysfunction.
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{
"pile_set_name": "NIH ExPorter"
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The two primary goals of Core C Bioinformatics and Integrative/Comparative Genomics Core are (1) to provide the common computational infrastructure and bioinformatics support for high-throughput, systematic data curation, exchange and translation, and (2) to develop, apply and automate computational integrative/comparative genomics methods on microarray-derived transcriptome data, across the different Project model systems. An integrative and comparative genomics approach will enable each Program Project to use diverse muscle and non-muscle transcriptome data sets from all Program Projects and the public domain to generate hypotheses about candidate genes, functional dependencies or pathways that are important in muscular dystrophies, muscle development and myogenic cell therapy. The approach combines information from public databases of bio-molecular functions and interactions, and multiple-genome sequence data to prioritize further experimental studies in the different model systems. The three aims of Core C are: (1) to establish an integrative computational infrastructure for data storage, curation and automated cross-systems matching of genomic data elements;(2) to develop and implement computational methods for integrative/comparative functional genomics;and (3) to use integrative/comparative genomics techniques to systematically identify or infer functional hierarchies underlying developmental aspects of muscle cells and specific myopathies for further experimental validation.
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{
"pile_set_name": "NIH ExPorter"
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Glioblastoma mutliforme (GBM) is the most common form of primary brain cancer. Despite aggressive therapies including surgery, radiotherapy, and chemotherapy, recurrent disease is nearly always fatal. Oncolytic HSV vectors (e.g. G207) have shown some promise in the treatment of GBM however there have been few complete responses, a disappointing outcome most likely related to inadequate vector infection and growth, particularly among tumor cells that migrate from the tumor mass and invade normal brain tissue. Thus a central goal of Project 3 is to improve oncolytic vector delivery, replication and spread while maintaining safety and tumor specificity. Because changes in the tumor microenvironment greatly influence virus growth, we propose further to arm these oncolytic vectors with genes that improve vector distribution, overcome local anti-viral responses and enhance susceptibility to apoptotic mechanisms. Specifically, we propose to: (i) to explore the growth, spread and anti-tumor potential of a highly active HSV -1 strain KOS Oncolytic Vector (KOV) deleted for the non-essential immediate early (I.E.) genes ICPO, ICP22 and ICP47, (ii) to employ a recombinant KOV vector expressing a secreted matrix metalloproteinase protease (ADAMTS-8) with strong anti-angiogenic activity in an effort to increase initial vector distribution and to facilitate vector spread during replication, (iii) examine the use of a recombinant KOV capable of expressing VH1, binl and a dominant negative IKB (kBaM) as inhibitors of the interferon gamma (IFNy) and indoleamine 2,3-dioxygenase (IDO) antiviral and cytokine induction pathways and (iv) to evaluate the ability of recombinant KOV expressing (a) a novel dominant negative PKCe (DNP) that blocks its anti-apoptotic function, (b) caspase 8a to launch the apoptotic cascade and (c) an optimized recombinant soluble TRAIL (orsTRAIL) to induce tumor cell apoptosis. Ultimately, it is our intention to create a powerful oncolytic vector that exploits these combined growth-facilitating, anti-tumor functions that will set a new standard for this form of glioma therapy. This new vector will be compared to G207 to demonstrate improved anti-tumor responses. The highly engineered vector will also provide opportunities to better understand glioma cell biology, greatly improve the use of anti-cancer drugs in collaboration with Project 1 and assist the induction of tumor-specific immunity in collaboration with Project 2. Together our replication competent gene vectors should be useful in the development of an effective multi-modal therapy, an important overall goal of our program project grant.
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{
"pile_set_name": "NIH ExPorter"
}
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PROJECT SUMMARY Diarrheal disease causes close to one million deaths in children under five each year. Although its incidence is much lower in the more affluent nations, diarrhea remains one of the two most common visits to pediatric emergency rooms and is also common among the institutionalized elderly. NHE3 is a major sodium transporter in the brush border membrane of the small intestine and proximal colon. Abnormal NHE3 expression and function are associated with diarrheal diseases resulting from acute pathogenic infection and inflammation in the gut. This application aims at understanding post-translational modification of human NHE3. The impetus of the proposed study comes from our recent finding that NHE3s of human and primates differ from NHE3s of lower mammals, including rodents and rabbits. Nedd4-2 is an E3 ubiquitin ligase that interacts with substrate proteins via PY (PPxY) motif. We found that human NHE3 (hNHE3) interacts with Nedd4-2, which ubiquitinates hNHE3 and mediates endocytosis, and the response of hNHE3 is much greater to forskolin/PKA than rabbit NHE3. Although mice have widely been used to understand the physiological role of NHE3, mice are relatively resistant to development diarrhea. We will examine the idea that ubiquitination of hNHE3 contributes to the increased severity of acute diarrhea in man. To begin, we will compare the regulation of hNHE3 and mouse NHE3 in vivo using transgenic animals. We will study how hNHE3 is endocytosed, recycled and degraded by Nedd4-2 mediated ubiquitination. Ubiquitination is counteracted by deubiqutination. We have identified several putative deubiquinating enzymes (DUBs) that interact with hNHE3. We plan to investigate how Nedd4-2 and DUBs dynamically regulated hNHE3. Our work is expected to reveal new mechanism for the control of intestinal brush border NHE3, and identify Nedd4-2 as a novel target for the therapeutic of diarrheal diseases caused by abnormal sodium and water balance in intestinal epithelium.
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{
"pile_set_name": "NIH ExPorter"
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DESCRIPTION (Investigator's Abstract) "This is an application to become a participating Clinical Center in the Ocular Hypertension Treatment Study (OHTS). The complete details of the OHTS rationale, design, and methods are contained in the OHTS Manual of Procedures. This proposal provides complete documentation of the ability of Scheie Eye Institute/University of Pennsylvania to screen large numbers of ocular hypertensive patients and to enroll at least 50 eligible patients over a 24-month period. Documentation is provided of the capabilities of the proposed investigators and their staff for the performance of the study in accord with the details of the OHTS Manual of Procedures, the nature and extent of their commitment to the Scheie Eye Institute of the University of Pennsylvania School of Medicine and Presbyterian Medical Center of Philadelphia, and a list of organizations/practitioners in the area who will refer or follow patients screened for enrollment and randomization to treatment in the OHTS clinical trial."
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{
"pile_set_name": "NIH ExPorter"
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The goals of the MBRS RISE Program at StMU are to 1) increase the number of disadvantaged minority students from StMU who pursue careers in biomedical research at the graduate level or as support personnel 2) increase the number of StMU faculty actively involved in biomedical research on the StMU campus. In order to accomplish these goals the following objectives have been identified. The objectives for goal 1 are to 1) recruit 10 students into a 10-week summer biomedical research program, 2) prepare these students to present their summer research projects, 3) provide workshops to introduce them to fundamental research techniques, 4) have students attend a weekly seminar series, and 5) provide individual counseling to support their interest in a career in biomedical research. The objectives for goal 2 are to 1) renovate existing space and provide small equipment funds to establish a new Faculty/Student Research and Development Laboratory, 2) develop a competitive program to provide faculty with seed money for pilot research projects, and 3) develop a program to provide funds for faculty to receive a travel grant to upgrade or update their research skills. StMU has recognized the importance of the RISE Program by committing funds to offset some of the costs associated with renovating and equipping the research and development laboratory. The objectives will be accomplished through a series of activities and the relative success measured in both quantitative and qualitative terms. It is projected that of the students recruited into the RISE program 2 - 3 per year will transfer into the MARC U STAR Program and eventually apply to graduate programs, while 2 - 3 of the remaining students will pursue careers in biomedical research. On the faculty side it is anticipated that the number of faculty conducting research on campus will increase from 0 to 5 and that the number of publications and grant applications will increase accordingly.
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{
"pile_set_name": "NIH ExPorter"
}
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Proteins function through their interactions, and the availability of protein interaction networks could help in understanding cellular processes. However, the known structural data are limited and the classical network node-and-edge representation, where proteins are nodes and interactions are edges, shows only which proteins interact; not how they interact. Structural networks provide this information. Protein-protein interface structures can also indicate which binding partners can interact simultaneously and which are competitive, and can help forecasting potentially harmful drug side effects. Here, we use a powerful protein-protein interactions prediction tool which is able to carry out accurate predictions on the proteome scale to construct the structural network of the extracellular signal-regulated kinases (ERK) in the mitogen-activated protein kinase (MAPK) signaling pathway. This knowledge-based method, PRISM, is motif-based, and is combined with flexible refinement and energy scoring. PRISM predicts protein interactions based on structural and evolutionary similarity to known protein interfaces.Apoptosis is a matter of life and death for cells and both inhibited and enhanced apoptosis may be involved in the pathogenesis of human diseases. The structures of protein-protein complexes in the apoptosis signaling pathway are important as the structural pathway helps in understanding the mechanism of the regulation and information transfer, and in identifying targets for drug design. Here, we aim to predict the structures toward a more informative pathway than currently available. Based on the 3D structures of complexes in the target pathway and a protein-protein interaction modeling tool which allows accurate and proteome-scale applications, we modeled the structures of 29 interactions, 21 of which were previously unknown. Next, 27 interactions which were not listed in the KEGG apoptosis pathway were predicted and subsequently validated by the experimental data in the literature. Additional interactions are also predicted. The multi-partner hub proteins are analyzed and interactions that can and cannot co-exist are identified. Overall, our results enrich the understanding of the pathway with interactions and provide structural details for the human apoptosis pathway. They also illustrate that computational modeling of protein-protein interactions on a large scale can help validate experimental data and provide accurate, structural atom-level detail of signaling pathways in the human cell.The KIX domain of CBP is a transcriptional coactivator. Concomitant binding to the activation domain of proto-oncogene protein c-Myb and the transactivation domain of the trithorax group protein mixed lineage leukemia (MLL) transcription factor lead to the biologically active ternary MLL-KIX-c-Myb complex which plays a role in Pol II-mediated transcription. The binding of the activation domain of MLL to KIX enhances c-Myb binding. Here we carried out molecular dynamics (MD) simulations for the MLL-KIX-c-Myb ternary complex, its binary components and KIX with the goal of providing a mechanistic explanation for the experimental observations. The dynamic behavior revealed that the MLL binding site is allosterically coupled to the c-Myb binding site. MLL binding redistributes the conformational ensemble of KIX, leading to higher populations of states which favor c-Myb binding. The key element in the allosteric communication pathways is the KIX loop, which acts as a control mechanism to enhance subsequent binding events. We tested this conclusion by in silico mutations of loop residues in the KIX-LL complex and by comparing wild type and mutant dynamics through MD simulations. The loop assumed MLL binding conformation similar to that observed in the KIX-c-Myb state which disfavors the allosteric network. The coupling with c-Myb binding site faded, abolishing the positive cooperativity observed in the presence of MLL. Our major conclusion is that by eliciting a loop-mediated allosteric switch between the different states following the binding events, transcriptional activation can be regulated. The KIX system presents an example how nature makes use of conformational control in higher level regulation of transcriptional activity and thus cellular events.NRF2 is a well-known, master transcription factor (TF) of oxidative and xenobiotic stress responses. Recent studies uncovered an even wider regulatory role of NRF2 influencing carcinogenesis, inflammation and neurodegeneration. Prompted by these advances here we present a systems-level resource for NRF2 interactome and regulome that includes 289 protein-protein, 7469 TF-DNA and 85 miRNA interactions. As systems-level examples of NRF2-related signaling we identified regulatory loops of NRF2 interacting proteins (e.g., JNK1 and CBP) and a fine-tuned regulatory system, where 35 TFs regulated by NRF2 influence 63 miRNAs that down-regulate NRF2. The presented network and the uncovered regulatory loops may facilitate the development of efficient, NRF2-based therapeutic agents.Allosteric drugs are increasingly used because they produce fewer side effects. Allosteric signal propagation does not stop at the 'end' of a protein, but may be dynamically transmitted across the cell. We propose here that the concept of allosteric drugs can be broadened to allo-network drugs - whose effects can propagate either within a protein, or across several proteins, to enhance or inhibit specific interactions along a pathway. We posit that current allosteric drugs are a special case of allo-network drugs, and suggest that allo-network drugs can achieve specific, limited changes at the systems level, and in this way can achieve fewer side effects and lower toxicity. Finally, we propose steps and methods to identify allo-network drug targets and sites that outline a new paradigm in systems-based drug design.
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{
"pile_set_name": "NIH ExPorter"
}
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Mutations in dysferlin cause muscular dystrophy, and the mechanism by which loss of dysferlin leads to muscular dystrophy is a fundamentally different than other forms of muscular dystrophy. Dysferlin is a membrane-associated protein that participates in vesicle trafficking events. In muscle this includes vesicle movement important for plasma membrane repair. Our work has also shown that dysferlin, like other members of the ferlin family, regulates vesicle recycling. We characterized myoferlin and Fer1L5, two highly related proteins to dysferlin to understand whether these proteins have overlapping function to substitute for dysferlin. These ferlin proteins each have at least six C2 domains, domains important for protein-membrane and protein-protein interactions. We identified that the first C2 domain of dysferlin binds negatively charged phospholipids in a calcium sensitive manner. We subsequently showed that ferlin C2 domains bind directly to carboxy-terminal Eps 15 Homology Domain (EHD) proteins, and that EHD proteins are required for ferlin intracellular trafficking. EHD proteins can induce tubule formation in vitro and in cell. We will study the interaction between ferlins, EHD, and Bin1 in the genesis of transverse tubule in muscle. We will then examine the mechanisms by which loss of ferlin proteins renders the muscle susceptible to detubulation and the molecular requirements to restore tubule formation and function. Finally, we will examine recycling events mediated by ferlin proteins. In each step, we will determine the domains of dysferlin, or the related myoferlin and Fer1L5 that mediate these events and assess whether restoration of these functions corrects the underlying pathology in dysferlin-associated muscular dystrophy.
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{
"pile_set_name": "NIH ExPorter"
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We shall continue invistigating the mechanism of mutation at the APRT locus in Chinese hamster, mouse, and human cell lines. Analysis of mutants will be done by DNA sequencing, and comparative studies with the mutated proteins. Among mutagenic effects, we are interested in studying the effect of aneuploidizing agents, which have been reported to cause a high frequency of mutations at this locus. In vivo mutagenesis will be paralleled by studies with in vitro mutagenesis. Regulation of transcription and translation of 'house keeping' genes will be studied using APRT as a model. This will be done by a combination of deletion mapping in the promoter region, CAT assays with promoter segments of the APRT gene linked to the CAT gene, and by analysis of DNA binding sites on the gene. The effect of enhancer elements and viral LTRs on APRT expression will be examined. We shall analyze the effect of placing the APRT gene under hormonal control on transcription, translation, and nucleotide pools. Comparative analysis of phosphoribosyltransferases from E. coli, Drosophila melanogaster, and mammalian sources show extensive aminoacid homology. We shall sequence the yeast APRT gene, and compare the nucleotide and aminoacid sequences. Using the approach of comparative sequence analysis, in vitro mutagenesis, and monoclonal antibody interaction, we shall define the functional domains of the protein.
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{
"pile_set_name": "NIH ExPorter"
}
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The Office of Research Training and Development (ORTD) serves trainees in Maryland and Montana, including Postdoctoral, Visiting and Clinical Fellows; Medical Students; Postbacs; Graduate Students; and Summer Interns. ORTD creates and conducts programs, seminars, and workshops, along with individual support for career counseling, interpersonal communication, and time management. Outreach and recruitment are also key endeavors, with the goal to recruit outstanding, competitive candidates for training positions. Katie Soucy, M.S., is the Training Director, and the office has a staff of six. ORTD provides ten annual programs : Annual Fellows Workshop; Intramural NIAID Research Opportunities (INRO); ORTD Sponsorship Program; Summer Internship Programs; the Summer Seminar Series; Grant Writing Seminar Series; Faculty Jobs Series; Graduate and Medical School Prep Seminars; RML Postbac Clinical Center Visit Week; and the Rocky-Beth Fellowship Program for MD and MT fellows . The Fellows Advisory Committee (FAC), comprised of predoctoral and postdoctoral fellows, was re-established this year. At monthly meetings, the members provide feedback and insight into the needs of fellows and work to plan the Annual Fellows Workshop. FAC members determine the overall agenda, invite speakers, read and evaluate abstracts, and select the NIAID Outstanding Mentor Award from the nominations submitted by their peers. The 13th Annual Fellows Workshop is scheduled for November 2019 and, with the help of the FAC, is focused on scientific research and active involvement from participants. Fellows have been asked to submit abstracts to present oral and poster presentations during the event and plenary speakers will both focus on their scientific research. Intramural NIAID Research Opportunities (INRO 2019), was postponed allowing time for a full evaluation of the program and to update language and processes to reflect official NIH-wide changes to policy regarding programs dedicated to the promotion of diversity and inclusion. INRO 2020 has been developed to match protocol and the updated application process will launch September of 2019, with recruitment taking place throughout Summer and Fall. The ORTD Sponsorship Program provides support for trainees who are identified by NIAID PIs as a strong addition to their research group and whose support in an NIAID lab contributes to the overall promotion of diversity and inclusion in biomedical sciences. The Summer Internship Programs provide research experience in NIAID labs. Program orientation sessions included resources available for trainees as well as guidance for making the most of their time in NIAID. The Summer Seminar Series was held, featuring DIR Principal Investigators (PIs) with unprecedented attendance from both summer interns and postbacs; Sixty-eight percent of the Maryland interns presented their research at the annual Poster Day. Grant Writing Seminar Series has evolved to provide fellows with the opportunity to participate in a comprehensive workshop that includes one-on-one feedback and individual assistance on grant writing. The Faculty Job Series was developed to provide a deeper look at the different types of faculty positions and tips for reviewing job listings in order to determine the level of research, teaching, and other responsibilities for each individual position. Medical and Graduate School Workshops were developed to meet the needs of the many postbac trainees who scheduled one-on-one meetings with Postbac Program Coordinator. These trainees were especially interested in a more in depth look at the process for determining next steps after a postbac and comprehensive guidance on the application and interview processes. RML Postbacs who are planning to apply for MD or MD/PhD Programs have the opportunity to apply and attend a week of clinical rounds and shadowing experience at the Clinical Center in Bethesda. During the week of the OITE Postbac Poster Day, the trainees come to Bethesda and are scheduled to attend different rounds in the Clinical Center; they are also encouraged to schedule informational interviews and attend other events while on campus and are expected to participate in the poster day. In 2019, three pre-med postbacs participated in this opportunity. The Rocky-Beth Fellowship Program was established for fellows in 2015 to foster collaborations among Maryland and Montana labs, enhance scientific understanding, and broaden exposure to career opportunities. The program supports activities such as: visiting labs to learn new scientific approaches; conducting informational interviews and attending activities to enhance professional and career development. A new database was developed to more comprehensively track NIAID trainees and alumni. Program coordinators and managers are also able to use this tool to track general involvement of trainees and individual meeting notes. Additionally, the office is the collecting publication and other data for current and former trainees to form metrics for reporting success outcomes. A new website and social media platforms were developed to further promote training in NIAID and expand the professional presence of NIAID training both internally and externally. Efforts to promote student research and writing has already encouraged more trainees to contact the office with news and written pieces to share.
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{
"pile_set_name": "NIH ExPorter"
}
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The catecholamine neurotransmitter dopamine (DA) functions in neural circuits across phylogeny to modulate both simple and complex behaviors. In humans, DA signaling modulates arousal, cognition, reward, and motor function. Deficits in DA signaling are associated with multiple neuropsychiatric and neurodegenerative disorders including schizophrenia, attention-deficit hyperactivity disorder (ADHD), and Parkinson's disease. Temporal and spatial regulation of synaptic DA signaling is controlled by the presynaptic DA transporter (DAT). DAT localization and activity appear to be highly regulated, though the identity of, and roles played by, many DAT regulators in vivo is ill-defined. In the nematode Caenorhabditis elegans, synaptic spillover of DA produced by pharmacological or genetic loss of DAT (DAT-1) induces a locomotory phenotype called Swimming Induced Paralysis (SWIP). Thus, worms lacking DAT (dat-1) paralyze in a few minutes after swimming in a small volume of water whereas wild-type (N2) worms swim continuously. SWIP is induced by the release of vesicular stores of DA and can be suppressed by genetic elimination of the post-synaptic DA receptor DOP-3. To reveal genes necessary for regulating synaptic DA levels, we propose to carry out a forward genetic screen in the nematode, selecting for animals that exhibit reserpine-sensitive SWIP. Mutant lines will be grouped based on their complementation by N2, dat-1 and dop-3, and after sequencing of the DAT-1 gene. Following the identification of complementation groups, SNP mapping and whole genome sequencing will be employed to map the sites of mutations. RNAi phenocopy and transgenic rescue of SWIP will be used to functionally validate observed base-pair changes. To determine if these genes regulate DAT, swip lines will be subjected to behavioral analysis, including automated analysis of swimming, response to exogenous DA on solid surface, response to DAT inhibitors/substrates such as imipramine and amphetamine, and the presence of wild-type levels of DA uptake as assessed in primary cultures and in heterologous systems. Transgenic expression of GFP-DAT-1 will be used to evaluate the effect of mutations on DAT trafficking in vivo, and to demonstrate the specificity of these genes for DAT trafficking. For mutations that induce reserpine and DOP-3 dependent SWIP independent of DAT-1, we will assess the contribution of altered DA release through the controlled firing of DA neurons using Channelrhodopsin-2 selectively expressed in DA neurons. As C elegans express the canonical genes that dictate DA biosynthesis, packaging, metabolism and reuptake, our SWIP-based forward genetic screen may reveal genes that both support DA signaling in the nematode and that are conserved in vertebrates, including humans.
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{
"pile_set_name": "NIH ExPorter"
}
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The long term objective of this proposal is to gather enough empirical data in order to predict the properties of proteins from their amino acid sequence. This is to be done for a family of small, rigid protein proteinase inhibitors - the avian ovomucoid third domains. The work consists of two phases: production of variants and measurement of various bird egg whites, protein semisynthesis and site specific mutagenesis. It is anticipated that about 200 additional variants will be produced in the next grant period. The properties will be measured in part in this laboratory and in part by many collaborators throughout the world. As ovomucoid third domains often are potent inhibitors of serine proteinases their interaction with bovine alpha chymotrypsin, porcine pancreatic elastase, subtilisin Carlsberg and Streptomyces griseus proteinases A and B is studied. We measure the equilibrium constant for enzyme-inhibitor association and the rate constants characterizing the interaction. Collaborators determine their dimensional structure of enzyme-inhibitor complexes and of free inhibitors. For inhibitors alone we measure the reactive site peptide bond hydrolysis equilibrium constant, Khyd and the denaturation equilibrium constant Kden. Various spectroscopy (UV, laser Raman, fluorescence, NMR and mass spectral) measurements are carried out as well as antigenic can chromatographic characterizations. The sequence data are all used to construct phylogenies of birds and to understand the unusual evolutional property of protein proteinase inhibitors: the hypervariability of enzyme-inhibitor contact positions.
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{
"pile_set_name": "NIH ExPorter"
}
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The projects described in this proposal are designed to evaluate the role of fetal brain tissue transplants in mediating functional recovery from traumatic injuries to the central nervous system. Using behavioral, anatomical and electrophysiological techniques, this project will examine whether: (a) the effectiveness of transplants in promoting behavioral recovery varies as a function of the time between the initial brain injury and the introduction of the fetal tissue into the host brain; (b) "recovered" behaviors are different than those used by intact animals--(i.e., is there restitution or substitution of behavioral functions induced by transplant surgery?); (c) the effectiveness of fetal brain tissue transplants can be enhanced by incubation in neurotrophic substances prior to implantation in the damaged host brain; (d) specificity of tissue between fetal tissue and host is an essential condition for obtaining functional recovery (e.g., can embryonic frontal cortex assist in facilitating behavioral recovery following occipital cortex lesions?); (e) interspecies transplants are effective in promoting functional recovery (e.g.,, can embryonic cortical tissue taken from the hamster be used to reduce lesion-induced, cognitive deficits in adult rats?); (f) specific anatomical connections formed between the host brain and the transplant material are necessary to mediate functional recovery. Although there are a number of new and exciting approaches to the study of neural plasticity, it is surprising how few are concerned with detailed analysis of the behavioral consequences of injury-induced changes in C.N.S. functions. Yet, understanding how the nervous system mediates, or can be induced to mediate, behavioral and functional recovery is the key issue for those faced with the prospect of treating the more than 400,000 patients who suffer severe C.N.S. injuries in this country each year. Any attempts to develop specific, effective and long-lasting treatments for the victims of brain and spinal cord injuries, should be given some attention. This proposal addresses the question of whether fetal brain cells can serve as one form of therapy for severe brain dysfunctions. Careful behavioral analyses, using complex learning tasks are followed by detailed electrophysiological and anatomical assays of the transplant effects. The long-term goals of this research are to find the means to alleviate some of the suffering caused by C.N.S. injuries and restore the patient to a more normal life.
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{
"pile_set_name": "NIH ExPorter"
}
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This is a pilot study to investigate differences in skin blood flow in persons with and without depression. Measurement of skin blood flow, which is under sympathetic control, is postulated to be a means of understanding the linkages between depression and the physiologic processes associated with ischemic heart disease.
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{
"pile_set_name": "NIH ExPorter"
}
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Anticipated Impacts on Veterans Health Care: The proposed project offers a potential solution to strengthening Veterans' self-management of chronic disease conditions through intervention to an easily accessible, self-management tool, the VA's PHR - My HealtheVet that fosters the knowledge and skill-building aspects of diabetes self-management. The proposed approach creates flexible and accessible strategies for increasing knowledge, developing self-monitoring skills, building self-efficacy and enhancing patient empowerment. Thus, active orientation to the use of MHV as a skill-building tool will foster adoption of proper self-monitoring behaviors. The proposed project serves to yield a more patient-oriented process in access to and quality of care, and disease management. Furthermore, this project will provide early evidence to increase adoption and use of MHV in disadvantaged Veteran groups. Background: Veterans bear a disproportionate burden of diagnosed diabetes at a 24% prevalence compared to 8.3% nationally. Patient-level factors account for >95% of patient care and health management. Poor patient knowledge/information and participation are two key factors responsible for the most prevalent disparities in the VA healthcare system for which patient activation and adherence interventions may help to reduce disparities in care, but patients have a low rate of engagement in self-care behaviors. Healthcare systems have established personal health records (PHRs), such as My HealtheVet (MHV), that enable patients to access their own health records, obtain health information, and communicate with providers about their disease conditions. This study proposes to activate patients and improve patient diabetes-related behaviors through development of an adapted brief MHV-driven patient activation and self-care intervention that enhances DSM skills (e.g., physical activity, diet, medication adherence, and self-monitoring) in high-risk, rural Veterans. Objectives: The objectives of this study are to: (a) Adapt a brief My HealtheVet (MHV) intervention to enhance its appropriateness for Veterans with diabetes increase patient activation and DSM skills; (b) test feasibility and preliminary effectiveness of the adapted brief MHV intervention on DSM skills in rural Veterans; and (c) evaluate Veterans' experience with the adapted brief MHV intervention and identify perceived barriers, facilitators, and enablers of its use, and assess the potential for wider dissemination. Methods: To achieve these objectives, we will develop an adapted brief MHV intervention that targets DSM skills. Training for features of My HealtheVet (setting goals, entering/tracking data, researching health-related information, secure messaging) will first be developed. We will obtain a nonrandomized sample of at least 20 rural Veterans, age 45+ years, with diabetes and either hypertension or hyperlipidemia from community- based outpatient clinics in the Charleston VA catchment area. The intervention will involve an initial in-person session with the rest of intervention sessions delivered remotely. In addition, weekly reminders (or booster messages) will be sent to each participant through the MHV secure messaging. All participants will undergo assessments at baseline and at 6 weeks follow-up. For those who agree, semi-structured telephone interviews will be conducted with study participants to evaluate Veterans' experience with learning and navigating MHV through the intervention and to assess feasibility, ease of use, and refinement for potential dissemination to a broader audience. Primary outcomes, frequency of and satisfaction with MHV use, and secondary outcomes, change in DSM skills and clinical indicators, will be assessed in all participants at baseline and at 6 weeks follow-up. Quantitative analysis will involve rate of adoption and mixed effects models. The primary qualitative analysis will involve cognitive interviewing and discourse analysis of semi-structured interviews.
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{
"pile_set_name": "NIH ExPorter"
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The specific aims of this proposal are to identify the formyl peptide receptor on alveolar macrophages and to determine its role (initiation, regulation, etc.) in the stimulation of O2- production by these cells. The formyl peptide receptor on the alveolar macrophage has thus far been poorly studied. However, since the macrophage has a significant role as a first line of host defense in the lung, the formyl peptide receptor (potential bacterial metabolite receptor) on the macrophage merits a thorough evaluation and characterization. To conduct the various aspects of this proposal, a number of radioactive and fluorescent derivatives of formyl peptides will be synthesized. With these, binding studies (kinetic, equilibrium and competitive) will be conducted to determine 1) if there are subpopulations of cells isolated by three techniques (density, affinity chromatography and cell sorter), 2) receptor cooperatively including receptors for other stimulators and 3) whether changes in membrane fluidity (anisotropy experiments) and receptor mobility are linked and what are the energetics of receptor binding. Some of the derivatives will be covalently bound to the receptor protein which will permit identification, isolation and measurement of chemical modification of the protein. Biophysical measurements (photobleaching, energy transfer and anisotropy) will be combined with visual techniques to determine what is the quality and quantity of receptor motion preceding and anteceding O2- production. Overall, these studies will permit a correlation to be made between the physical properties (i.e., binding, mobility and cooperativity) of the formyl peptide receptor (i.e., putative physiological bacterial metabolite receptor) and biological properties of the cell (i.e., O2- production and down regulation). If regulation of O2- production (possibly granular enzyme release and chemotaxis) is at the receptor level, then an understanding of this phenomenon would facilitate possible control of these processes. Where possible, extrapolation will be made to the human system.
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{
"pile_set_name": "NIH ExPorter"
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Although there is no evidence that ZDV or DDI are cures for AIDS or HIV infection, current data suggest that ZDV and DDI may prolong life and decrease infections for some individuals who have AIDS or severe ARC. Participants may derive no specific benefit from being in the study but may be making a valuable contribution to science and medicine by helping doctors better understand how to treat children with HIV infection.
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{
"pile_set_name": "NIH ExPorter"
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Abstract Alcohol screening and brief intervention (SBI) is one of the most effective and cost-effective preventive health services, and SBI to address unhealthy use of alcohol and other drugs has been a significant focus of research, policy, and clinical programs in the US. Yet many unanswered research questions remain, including how to deliver alcohol SBI in regular clinical practice, how to effectively intervene with respect to drug use, and how new approaches could be applied to increase the reach and effectiveness of interventions. It is essential for researchers to come together now to share their knowledge and map the next phase of SBI research. To provide a forum for knowledge exchange, an alcohol and drug SBI conference is planned for New York, NY, September 14-15, 2017. The conference will be the 14th annual meeting of the International Network on Brief Interventions for Alcohol and Other Drugs (INEBRIA), and represents only the third such meeting to be held in the US. INEBRIA is the only organization in the world dedicated to SBI research on alcohol and other drugs. INEBRIA's goals include translating evidence for SBI into practice, identifying and promoting SBI best practices, identifying SBI research gaps and needs, promoting international research cooperation, and setting standards for research in the field. The conference theme `Screening and brief intervention at the intersection of research, policy and practice: Advancing knowledge and meeting new challenges' highlights a focus on practice-based research that informs policy and can impact health at the population level. The goal of this INEBRIA research conference is to present findings from and promote further development of SBI research, with a particular emphasis on implementing and scaling up what works, and finding new approaches to addressing unhealthy substance use (including alcohol and other drugs) that are feasible, effective, and sustainable. The specific aims are: (1) to communicate and disseminate research findings about SBI implementation and dissemination, SBI in the larger context of behavioral health, and new advances in SBI research, (including digital platforms and interventions targeting adolescent substance use); (2) to increase collaboration among SBI researchers across the US and worldwide; and (3) to engage junior researchers in SBI research and provide them with a forum for presenting their work and finding mentoring opportunities. The 2017 INEBRIA conference will convene a large and diverse group of researchers in an epicenter of substance use research, New York, NY, for 2 days of research presentations and discussions. Conference planning committees have been convened. The program will include plenary sessions, research abstract presentations and workshops, and a poster session. Abstracts will be peer reviewed by the Scientific Committee, which will select those that present high quality research on alcohol or drug SBI. The 2017 INEBRIA conference will clarify the state of research science related to SBI through international discussion and collaboration, and presents a unique opportunity to advance the field.
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{
"pile_set_name": "NIH ExPorter"
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Filariasis is a major public health problem in a number of developing countries, where there are an estimated 100 million cases of the lymphatic form. One of the major problems in the study of filariasis is the lack of an optimal animal model. The overall goal of the proposed research is to increase our understanding of the immunopathogenesis of lymphatic filariasis through the study of the biology of Brugia malayi infection in the C.B. 17-scid/scid mouse (hereinafter referred to as the scid mouse). In preliminary studies, detailed below, we have found that the scid mouse will indeed permit the maturation of injected B. malayi larvae to the adult stage. In addition, when the larvae are injected subcutaneously, some migrate to the lymphatics where they give rise to lyphangiectasis, lymphangitis and lymphatic stasis. These observations indicate that B. malayi infection of the scid mouse may be a good model for human lymphatic filariasis in that it recapitulates several important pathological features of human infection. The present proposal is intended: (1) To more completely document the pathological changes caused by B. malayi infection in the scid mouse. (2) To determine the fate of B. malayi L3 larvae in scid mice reconstituted with lymphoid cells or serum from naive, coisogeneic C.B.-17 wild type animals. (3) To use the scid mouse as a model system to screen the efficacy of potential vaccine candidate antigens identified in the laboratory of the PI using recombinant DNA technology. The long term goal of these studies is to investigate the role of the human immune system in the protection from or pathogenesis of filariasis. The most attractive feature of the scid mouse is its ability to support the maturation of a human immune system when appropriately reconstituted. The establishment and characterization of the scid mouse of filiariasis as detailed in this proposal will provide the basis for our future efforts to investigate the role of the human immune response in the pathogenesis of filariasis.
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{
"pile_set_name": "NIH ExPorter"
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The objective of this proposal is a genetic analysis of the regulation and control of meiosis in male Drosophila melanogaster. We are using two systems to analyze this problem; the analysis of mutants which affect chromosome behavior in meiosis and the analysis of the segregation patterns of translocation and compound autosomes. Two meiotic mutants are being examined. One mutant permits nonhomologous pairing. Studies with this mutant are designed to explore the parameters of the nonhomologous pairing. The second mutant affects the second meiotic division and is chromosome specific. The nature of this specificity will be examined. Various chromosomal aberrations will be analyzed with respect to their segregation patterns. These will include Y - 2 translocations and compound autosomes. In the translocations, we have found that certain types of segregation do not occur. Some compound autosomes do not segregate randomly in males. We anticipate the results from our studies on translocation segregation and compound autosome segregation will permit us to identify those heterochromatic regions that are necessary for chromosome pairing.
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{
"pile_set_name": "NIH ExPorter"
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The objective of this program is to understand the genetic control of malignancy in human cancer cells and the mechanisms of malignant transformation by oncogenic viruses through genetic, immunological and biochemical approaches. The backgrounds in somatic cell genetics, tumor virology, immunology, molecular biology and biochemistry of the investigators involved in this program will be exploited to gain insight into the mechanisms of malignant transformation and into the processes leading to the expression of malignancy.
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{
"pile_set_name": "NIH ExPorter"
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This application requests four years of funding to establish a Conte Center to Develop Collaborative Neuroscience Research. Through the Center, we intend to test a comprehensive, novel hypothesis about the function of sleep - the synaptic homeostasis hypothesis. The hypothesis states that plastic processes during wakefulness result in a net increase in synaptic strength in many brain circuits, leading to increased metabolic consumption. Strengthened brain circuits then lead to larger slow waves during subsequent sleep. In turn, sleep slow waves renormalize synaptic strength to a baseline level that is energetically sustainable and beneficial for memory and performance. Sleep is therefore the price we pay for plasticity, and its function is the homeostatic regulation of the total synaptic weight impinging on neurons. The hypothesis accounts for many facts about sleep and its regulation and makes intriguing predictions that are relevant for both basic and clinical neuroscience. We propose to test such predictions through four tightly linked and complementary projects, to be carried out jointly at the University of Wisconsin and at Washington University. Project I (PI Cirelli) employs a combined molecular / electrophysiological approach in an animal model to establish a relationship between synaptic potentiation during waking, an increase in sleep slow waves, and the resulting synaptic renormalization; Project II (PI Tononi) employs behavioral / high-density (hd)-EEG paradigms in healthy human subjects to determine whether learning leaves a local EEC trace in both wakefulness and sleep, and to determine whether sleep slow waves are necessary to renormalize this trace; Project III (PI Raichle) employs the same behavioral paradigms in conjunction with PET and fMRI to investigate whether learning leaves a local metabolic trace that is renormalized by sleep; and Project IV (PI Benca) employs the same behavioral / hd-EEG paradigms in patients with major depression to evaluate a predicted relationship between preserved slow wave homeostasis and therapeutic response to sleep deprivation. If the hypothesis survives these combined tests, it will provide a scientific explanation of why we need to sleep that ranges all the way from molecular and cellular function to systems neurophysiology and neuroimaging. Given the central role of sleep in the life of every organism, at every age, we expect that the results of our program will have major implications for many aspects of human health and disease. [unreadable]
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{
"pile_set_name": "NIH ExPorter"
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Our previous studies indicated that certain pseudo-diploid SS-teratocarcinoma stem cell lines contain two genetically active X-chromosomes as long as they are maintained in the undifferentiated state, and that the cells can undergo X-inactivation when they are allowed to differentiate in vitro. We propose here to further explore the extent to which such cells can provide a valid model system for the study of X-inactivation. To do this, we will isolate new teratocarcinoma stem cell lines by a variety of techniques, including fusion with microcells derived from M. caroli fibroblasts, to obtain cells that are heterozygous for electrophoretic variants of X-linked enzymes. The availability of such cell lines will enable us to confirm by enzyme gel electrophoresis our earlier conclusions. In other experiments we will study the cytogenetic properties of the X-chromosomes in the cells to determine the temporal relationship between the onset of the cytological manifestations of X-inactivation (e.g. late replication of DNA) and of biochemical inactivation. In addition, we will determine whether an inactive X-chromosome can be reactivated by placing it in a teratocarcinoma stem cell.
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{
"pile_set_name": "NIH ExPorter"
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Studies are to be carried out, mostly in vitro, to characterize complicated cellular reactions which lead to inactivation of repressor molecules. These will be based on the biochemical assay procedure which we have recently established. Using permeable and complete in vitro systems, attempts will be made to isolate and identify cellular components which are involved in prophage induction and in genetic recombination in E. coli. BIBLIOGRAPHIC REFERENCES: Smith, C.L. and M. Oishi (1976). The Molecular Mechanism of Virus Induction. I. A Procedure for the Biochemical Assay of Prophage Induction. Molec. Gen. Genet. 148: 131-138. Oishi, M. and R. Irbe. Circular Chromosomes and Genetic Transformation in Escherichia coli. In: Bacterial Transformation and Transfection, Eds. Portoles/Lopez/Esponosa (1976, in press). Elsevier/North-Holland Biomedical Press, Amsterdam, The Netherlands.
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{
"pile_set_name": "NIH ExPorter"
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The major objective of this work is to isolate, purify and determine the structure of the antitumor alkaloids present in Catharanthus roseus, Catharanthus trichophyllus and Rhazya stricta. The Malagasy plant Catharanthus roseus is a well established source of antitumor agents of the dimeric indole alkaloid class. However several highly active fractions remain to be studied for their constituents. The crude alkaloid mixtures will be separated initially by pH gradient techniques and subsequently by column chromatography; monitoring each step with an appropriate biological assay technique. Isolated compounds will be identified by their mp, mass UV and IR spectra, optical rotation CD and PMR spectra. Structure elucidation will be carried out by interpretation of these data, chemical correlation with known compounds and in particularly difficult cases by single crystal X-ray crystallography.
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{
"pile_set_name": "NIH ExPorter"
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DESCRIPTION:(Adapted from Investigator's abstract): Wegener's granulomatosis is a relapsing vasculitic disease of unknown etiology that carries a severe prognosis and responds poorly to current relatively toxic immunosuppressive therapy. Our working hypothesis is that there is an infectious agent(s) associated with induction or progression of Wegener's. We were funded via a supplement to RO1 AI39616 (HWV, investigator) to develop both degenerate primer PCR (Deg-PCR) and representation difference analysis (RDS) for purposes of pathogen discovery. We are now prepared to use these assays, and two additional methods, to seek candidate pathogens involved in human diseases. Key to this proposal, the combination or our expertise in molecular techniques and infectious diseases, and the clinical resources and protocols of the ongoing Wegener's Granulomatosis Etanercept Trial (WGET, Appendix A), provides a unique and unlikely to be duplicated opportunity to search for an infectious etiology of Wegener's granulomatosis. This proposal has four Aims. If candidate pathogens are identified, two contingent Aims will be pursued. Aim 1) Identify candidate pathogen(s) associated with the induction or progression of Wegener's granulomatosis using culture on human fibroblasts; Aim 2) Identify candidate pathogens(s) associated with the induction or progression of Wegener's granulomatosis using specific and degenerate PCR; Aim 3) Identify candidate pathogen(s) associated with the induction or progression of Wegener's granulomatosis using representational difference analysis (RDA); Aim 4) Identify candidate pathogen(s) associated with the induction or progression of Wegener's granulomatosis using inoculation of severely immunocompromised mice; Contingent Aim A) Development of assays for detecting candidate pathogen(s) associated with Wegener's granulomatosis; Contingent Aim B) Analyze the prevalence of infection in the patients taking part in the associated WGET trial, and control patients. We have assembled a team of co-investigators with expertise including clinical rheumatology, clinical trials, infectious disease, molecular biology, molecular pathogenesis, and statistics. The benefits of identifying potential etiologies for Wegener's are great, preliminary data shows that the methods are in hand, and the team assembled is well qualified to undertake the proposed studies.
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{
"pile_set_name": "NIH ExPorter"
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Major efforts included: (1) Analysis of joint risk of lung cancer from exposure to radon, arsenic and tobacco products; (2) data acquisition from large scale case-control and cohort studies in Gejiu City, China to further quantitate these relationships; (3) analysis-of data on risk of thyroid; cancer following exposure to radiation of the head and neck; (4) evaluation of case-control data on dietary risk factors for esophageal cancer; (5) evaluation of fecal mutagens; (6) studies of the effects of treatment for childhood cancer on subsequent rates of menopause and on patterns of marriage and divorce; (7) application of the method of backcalculation for projecting AIDS incidence and for estimating previous trends in infection for various subgroups of the population; (8) assisting members of the Viral Epidemiology Section on the design and analysis of studies of natural history, transmission rates, and biological markers in cohorts of hemophiliacs and infants exposed to HIV; (9) evaluating DNA fingerprints as an aid to quality control in tissue culture laboratories; (10) monitoring clinical trials of nutritional supplements to prevent cancer, of interventions to reduce smoking, and of therapies to prevent AIDS among infected groups; (11) providing consultation on the use of newly developed computing packages for epidemiologic analysis, and providing consultation on statistical methods to analyze error-prone exposures.
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{
"pile_set_name": "NIH ExPorter"
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Knowledge gained from this study will provide nurses with a means of evaluating the developing mother-preterm infant relationship, and a method to facilitate the development of positive relationships between mothers and their preterm infants. The proposed project will investigate the acquaintance process between mothers and their preterm infants following implementation of a Mother-Preterm Infant Acquaintance Strategy. Fifty-six primiparous mother-preterm infant pairs and 56-multiparous mother-preterm infant pairs (subdivided into 2 groups: 28 mothers with prior term deliveries and 28 mothers with prior preterm deliveries) will be randomly assigned to one of four groups within a block designated as "parity/prior delivery experience" (RBF-pq). The maternal-preterm infant acquaintance behaviors of 56 pairs (Groups 1 and 2) will be presented during a feeding episode during the first week of the infant's hospitalization. Also, 56 of the mothers (Groups 1 and 3) will receive the intervention (Maternal-Preterm Infant Acquaintance Strategy), which consists of Crisis Intervention, Maternal Orientation to Newborn Behaviors, and Infant Language Program. Subsequently, the mother-preterm infant pairs will be observed at home during a feeding episode to determine each pair's adaptive behaviors. Differences between the groups will be measured by 3-way analysis of variance (pretest x intervention x parity).
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{
"pile_set_name": "NIH ExPorter"
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Osteoporosis is an enormous public health problem that contributes to over 1.5 million fractures in the U.S. yearly. Current therapies modestly reduce fracture risk but no agent is able to fully restore skeletal integrity in most patients. Thus, there remains an urgent need for more effective treatments, particularly for those with severe disease. In the DATA study, we reported that when postmenopausal osteoporotic women are treated with the anabolic agent, teriparatide, along with the antiresorptive RANKL inhibitor, denosumab, bone mineral density, cortical bone microarchitecture, and estimated bone strength improve more than with either drug alone or with any available single agent. The superior efficacy of this combination approach appears to be related to denosumab?s ability to fully inhibit teriparatide?s pro- resorptive effects while still allowing for teriparatide-induced modeling-based bone formation. In a follow- up study currently underway (DATA-HD), we now demonstrate that using a higher dose of teriparatide in combination with denosumab increases bone density even more quickly and extensively than the regimen used in DATA, resulting in improvements in bone mass unachievable with even long-term use of any single agent. Given these extremely encouraging findings, it is now crucial that this approach be evaluated for its potential to reduce fractures in patients with severe osteoporosis. Such a demonstration will permit this regimen to be available as a treatment option for those patients at the highest risk of fragility fracture. This proposal aims to complete the planning of a double-blind placebo-controlled clinical trial that tests the hypothesis that in women with severe osteoporosis, 12-months of combined high-dose teriparatide and denosumab followed by 12-months of denosumab monotherapy will decrease fracture incidence substantially more than the current standard of care (oral alendronate treatment). To achieve this aim, we will collaborate an experienced coordinating center to identify optimal study sites, complete the detailed protocol and analysis plan, prepare an efficient budget, construct appropriate consent forms, and finalize a detailed and thorough manual of operating procedures. We will also prepare submissions to regulatory agencies and complete rigorous staff training. Given the unique potential of this novel therapeutic approach, the successful planning and completion of this comparative-efficacy trial has the potential to introduce a groundbreaking framework in osteoporosis therapy and substantially advance the treatment of patients with the most severe form of the disease.
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{
"pile_set_name": "NIH ExPorter"
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The utility of intramolecular anodic olefin coupling reactions involving electron-rich aromatic rings for constructing fused, bicyclic ring skeletons has been examined. Reactions involving alkoxysubstituted phenyl rings were found to benefit strongly from a 3-methoxy substituent on the phenyl ring. Although overoxidation of the bicyclic product was observed in these reactions, this problem could be minimized with the use of controlled potential electrolysis conditions when a monomethoxy phenyl ring was used and avoided entirely with the use of a vinyl sulfide moiety as the initiator when a more electron-rich phenyl ring was used. Reactions involving 4-alkoxy-substituted phenyl rings as substrates did not lead to good yields of fused products. Furan rings were found to be excellent coupling partners for the reactions and afforded products having fused, bicyclic furan ring skeletons. Cyclizations involving furans were shown to be compatible with the formation of both six- and seven-membered rings, the generation of a quaternary carbon, and the use of a variety of electron-rich olefins as the other coupling partner. It appears that the furan can serve as either the initiating group or the terminating group for the cyclizations. Finally, the reactions were shown to be compatible with the use of a pyrrole ring as one of the participants.
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{
"pile_set_name": "NIH ExPorter"
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Adolescent partner violence (APV) is an important social and health problem with potentially dire consequences. Youth exposure to IPV is also a problem, and children from families characterized by IPV, compared to children from nonviolent families, are more likely to act violently toward their own dating partners and spouses. However, not all youth exposed to IPV go on to act violently toward others. In fact, although the witnessing of IPV increases risk for perpetration of APV, many youth who witness IPV do not become violent in their intimate relationships. Unfortunately, very little is known about why some youth in families characterized by IPV are violent in later relationships, while others are not. The primary goals of the proposed research are to (a) identify potentially malleable variables that predict APV perpetration over a period of 6 months in a sample of youth whose families are characterized by IPV, (b) evaluate the utility of conceptual models derived from empirical research and theory for predicting the perpetration of APV, and (c) develop and test a comprehensive conceptual model that subsumes other, more circumscribed models for predicting the perpetration of APV. The proposed research will recruit and follow approximately 240 14- to 17-year-olds over a 6- month period. Adolescents and their mothers will be recruited from agencies providing services to families characterized by IPV (DV agencies, courts). Comprehensive assessments will be conducted at two separate time points, 3 months apart. Phone assessments of APV will be conducted every 2 weeks throughout the 6-month participation period. Specifically, each comprehensive assessment will be followed by a 6-month series of telephone contacts with the adolescents to obtain data on APV. During each of the comprehensive assessments, data will be collected directly from the adolescents, their mothers, and a friend nominated by the adolescents. During the biweekly assessments, data will be collected from the adolescents. This research will offer insights into the processes that shape the etiology of APV for adolescents growing up in highly stressful circumstances. In addition to its contributions to science, the proposed research will inform intervention and prevention programs designed for adolescents from violent homes. Identification of risk and protective factors and the processes by which they predict APV will facilitate the development of targeted interventions designed to prevent or arrest the development of APV.
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{
"pile_set_name": "NIH ExPorter"
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Modulation of opioid gene expression is preceded by the transcription of the AP-1 transcription factors in the brain. The AP-1 transcription complex is composed of two families of proteins: c-fos and fos-related antigens (fra) and the 3 jun proteins. These proteins form heterodimers which recognize and bind to the AP-1 DNA element in the promotor area of the genes. Through this mechanism, gene transcription is modulated. Both the prodynorphin (pDYN) and the proenkephalin (pENK) genes contain AP-1 elements in their promotor regions, suggesting that these factors regulate these genes. We have been examining whether these transcription factors regulate these peptide genes in the rat brain and adrenal gland. Acute administration of the seizure-inducing drug, kainate, induces AP-1 protein expression and modulates the expression of both pDYN and pENK genes in the rat hippocampus. Using anticonvulsants to block kainate-activated neuronal activity, AP-1 protein expression and DNA binding are both inhibited as well as the increase in opioid gene expression, demonstrating the expression of both opioid gene expresssion and AP-1 proteins are correlated with neuronal activity. During development, rat pups at any age ae susceptible to seizure activity after kainate; however, neither the AP-1 proteins nor the opioid genes are induced in the hippocampus until postnatal day 14. Of interest, the postnatal day 7 hippocampus contains a high basal level of AP-1 DNA binding, which seems to be due to the development of glial cells. Therefore, there is a development-dependent regulation of the expression of AP-1 proteins and opioid genes in the hippocampus after seizure activity. Kainate treatment also causes neuronal death in the hippocampus which leads to reactive gliosis. During reactive gliosis, glial cells increase expression of many peptides including proenkephalin. We have found an increased level of AP-1 DNA binding in areas of reactive gliosis, suggesting AP-1 transcription factors may be modulating gene expression in reactive glia.
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{
"pile_set_name": "NIH ExPorter"
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One challenge facing a postlingually-deafened adult cochlear implant (CI) user is the possibility that there may be a frequency mismatch between the incoming acoustic signal and the characteristic frequency of the neurons stimulated by the implant. While listeners can clearly adapt to frequency mismatches, there is a lack of information that can allow us to separate the adaptation to frequency mismatches from other distortions that CI users face. In the proposed experiments, we address this issue by examining CI users who have residual hearing in the contralateral ear. Given that frequency mismatches are often heard perceptually as a change in the pitch of the signal relative to the representation stored in long-term memory, we plan to compare the pitch percepts elicited by electrical stimulation with those from the acoustic hearing in the contralateral ear, and observe whether those percepts change over time. Our assumption is that such changes in electrical pitch perception indicate adaptation to a frequency mismatch. By this line of logic, we plan to address the issue of quantifying adaptation to frequency mismatch via three experiments. In the first experiment, we plan to ask CI patients who have sufficient residual hearing in the contralateral ear to match the pitch elicited by stimulation of a given electrode to the pitch elicited by a tone presented to the acoustic-hearing ear. We plan to follow these pitch matches over the first two years of device use, and determine whether changes in pitch perception are also related to changes in speech perception. In the second experiment, we plan to determine the cochlear size and the location of the electrode within the cochlea. From this, we can estimate the amount of frequency mismatch that a given CI user faces. Then, using the data obtained in Experiment 1, we will explore whether larger initial frequency mismatches are associated with larger amounts of adaptation, or with worse overall performance. Finally, in the third experiment, we plan to track electric-acoustic evoked interactions in the P1-N1-P2 complex over the first two years of device use in order to obtain an objective measure of adaptation to frequency mismatch. Taken together, these proposed experiments represent one of the first attempts to quantify the amount of frequency mismatch a given patient has, and the extent to which they are able to adapt to that mismatch. As such, they address a significant lack of knowledge in the cochlear implant field. More importantly, the information gained from these proposed projects has the potential to directly shape future fitting of cochlear implants, and may have an effect on patient care. Here, we propose the use of novel techniques to address this key issue, and as such, we believe that the proposed research has a strong translational component that may ultimately benefit public health for hearing-impaired populations. PUBLIC HEALTH RELEVANCE: Cochlear implants help many people hear, but the signal they provide can be significantly different from that provided by an intact auditory system. Patients who had acoustic hearing, lost it, and then received a cochlear implant, must adapt to the mismatch between the signal provided by the implant and the representations of speech that are stored in their long-term memory. The present study will investigate this adaptation process using behavioral and physiological measures, and this information may assist clinicians in helping patients optimize the benefit they obtain from their device.
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{
"pile_set_name": "NIH ExPorter"
}
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This project investigates the neural mechanisms of individual differences in amphetamine effects. Amphetamine has acute euphoric mood and alerting effects. These effects vary between individuals, are stable over time, and appear to be mediated by genetic factors. Recent placebo controlled studies indicate that the personality or emotional temperament of the individuals exposed to this drug play a role in these effects. To date, the personality trait of fearless sensation seeking is the strongest predictor of physiological and mood effects of amphetamine. In contrast, individual differences in the acute behavioral effects of amphetamine are less well understood, but appear to involve extraversion, a separate personality trait related to the sensitivity to reward. Thus the broad, long-term objective of the current application is to provide the empirical foundation for an in-depth study of the neural foundations of individual differences in psychostimulant drug effects using fMRI. The study utilizes a two-session, placebo-controlled amphetamine administration procedure, to provide pilot data regarding the functional alterations induced by amphetamine. Major aims are to investigate individual differences in amphetamine-induced increase in the neural activity and regions of activation associated with reward-related and punishment-related signal processing. Participants will be drawn from the extreme quartiles of scores on Tellegen's Agentic Positive Emotionality and will also vary in Harm Avoidance, which are the robust, empirically derived measures of extraversion and fearless sensation seeking that predict 40% - 50% of the variation in the acute impulsive and euphoric effects of amphetamine. Individual differences in amphetamine-induced BOLD signal will be assessed on three tasks: the Behavioral Analogue Risk Task (BART), International Affective Picture Set (lAPS), and Emotional Stroop task, in order to provide information about individual differences in the neural correlates of amphetamine effects on behavioral impulsivity, emotional reactivity, and attentional tasks that involve rewarding and punishing stimuli. In toto, the proposed pilot aims to use laboratory methods to identify neural predictors of a biobehavioral vulnerability to psychostimulant drug effects in normal populations, a goal with substantial health relevance for understanding the biological vulnerability factors for the initiation of drug use and abuse.
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{
"pile_set_name": "NIH ExPorter"
}
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Long term goals of this project are to determine the biotin requires for normal individuals in circumstances in which biotin status may be impaired and to investigate the consequences and pathogenic mechanisms for marginal biotin deficiency. We recently demonstrated that marginal biotin deficiency is common during normal human gestation and have demonstrated that marginal deficiency is quite teratogenic in mice. Thus, the following five specific aims are relevant and timely. In Specific Aim #1, we will test the hypothesis that maternal biotin deficiency causes abnormal development of fetal skeletons and palate by causing deficient fetal activity of the biotin-dependent enzyme acetyl- CoA carboxylase which leads in turn to deficiency of arachidonic acid and prostaglandin. In fetal palate and limb bud explants from biotin deficient and sufficient CD-1 mice, we will quantitative fetal arachidonic acid component and synthesis rates and will examine the malformation ameliorating effects of supplementation of arachidonic acid and prostaglandin and the amelioration blocking effects of cyclooxygenase inhibitors. Analogous studies will also be conducted in vivo. In Specific Aim #2, we will test the hypothesis that infants with cleft plate or limb shortening have significantly reduced biotin status compared to normal infants. In a case-controlled study, biotin status will be assessed in cord blood using odd-chain fatty acid composition in red blood cell membranes and plasma and lymphocyte activity of the biotin-dependent enzyme propionyl-CoA carboxylase. In Specific Aim #3, we will clone and sequence a biotin transporter recently discovered in our laboratory. In studies of cells from the first individual with biotin transporter deficiency, we will investigate the molecular nature of the genetic defect. In Specific Aim #4, we will confirm promising new indicators of biotin status and investigate the validity of the expression of particular biotin- related genes (e.g., carboxylases) as indicators of marginal biotin deficiency in healthy adults rendered marginally biotin deficiency by egg-white feeding. In Specific Aim #5, we will determine the subcellular localization of the enzyme(s) responsible for catalyzing the beta- oxidation of biotin to the inactive metabolite bisnorbiotin and characterize this pathway. Understanding of this pathway is important because accelerated biotin catabolism may be the major cause of biotin deficiency in pregnancy and anticonvulsants.
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{
"pile_set_name": "NIH ExPorter"
}
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Little is known concerning the mechanism of action of the polypeptide hormone relaxin. Since most polypeptide hormones exert their biological effects by binding to specific receptor sites on the cell membranes of target tissues, it is proposed to investigate this initial step in the mechanism of action or relaxin. Therefore, one objective of this research proposal is to establish and characterize receptor sites for relaxin in the uterus, cervix, and mammary gland of the rat under different hormonal states of the animal. Binding will be analyzed using I125 labeled relaxin by means of gamma ray spectroscopy and autoradiography. Binding data will be correlated with the hormonal state of the animal. Factors which regulate relaxin synthesis and/or secretion are not known. It is proposed to establish an organ culture system for rat corpora lutea of pregnancy or a rat luteal cell culture. Upon establishment of such a culture system, factors which influence relaxin synthesis and secretion will be investigated by means of ultrastructural studies and immunoprecipitation.
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{
"pile_set_name": "NIH ExPorter"
}
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Under auspices of this R01 grant we have cloned the bHLH transcription factors Olig1 and Olig2. We have shown that these proteins regulate diverse functions in central nervous system development including specification of motor neurons and oligodendrocytes. The research described here builds upon progress made in the initial funding period. We have three specific aims: Specific Aim 1 is to define cis- and trans-acting regulatory elements that govern Olig2 expression in the embryonic spinal cord. Our initial focus is on elements driving Olig2 expression during neurogenesis. We have isolated a human Chr. 21-derived BAG clone that encompasses OLIG2 and approximately 116 kb of flanking material. Regulatory elements within this clone are sufficient to rescue motor neuron and oligodendrocyte specification in transgenic mice that are Olig2 null. Preliminary analysis leads to the testable hypothesis that TALE-HoxA class homeodomain proteins bind the enhancer resulting in Olig1 activation specifically in neuroblasts. Specific Aim 2 is to test the hypothesis that diverse neurogenic and gliogenic functions of Olig2 are regulated by phosphorylation. In preliminary studies we provide compelling evidence that a pair of protein kinase C (PKC) phosphorylation motifs in the carboxyl terminal domain control neurogenic functions of Olig2. We will knock phosphorylation state mutations of these PKC motifs into the wild type Olig2 locus and assess for biological function in developing mice. We will screen for additional phosphorylation sites that are biologically relevant using in ovo electroporation and state-of-art mass spectroscopy techniques. Specific Aim 3 is to define the role of Olig expression in glioma. In preliminary studies of more than 200 human brain tumors, we have noted that the Olig genes are expressed in 100 percent of human gliomas;moreover, it is the cycling cells within these tumors that are selectively Olig-positive. We will utilize contemporary genetic models of glioma to discriminate between three testable hypothesis: i) all gliomas arise from Olig-positive neural progenitor cells, ii) Olig genes are stringently required for proliferation/survival of glioma stem cells, iii) Olig1 and Olig2 are reporter genes for a signaling pathway common to all gliomas. The proposed work will shed light on fundamental mechanisms that regulate development of the normal brain from multipotent neural progenitor cells. Identification of regulatory factors for glial progenitor cell specification and differentiation will have practical overtones for the therapy of glial-based diseases such as multiple sclerosis and malignant glioma.
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{
"pile_set_name": "NIH ExPorter"
}
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APPLICANT'S ABSTRACT: Alcohol abuse among adolescents is a pressing health concern with serious consequences for the drinking youth and society, including juvenile delinquency, school dropout, traffic injuries, and fatalities, violence, suicide, and AIDS risk behaviors. Although the magnitude of the problem has stimulated a dramatic increase in research attention in recent years, the field of adolescent alcohol abuse is characterized by an absence of controlled clinical trails of intervention programs, and few efficacious, replicable, and enduring treatment strategies have been identified. Moreover, there continues to be a gap in the treatment literature integrating theoretical treatment formulations and empirically derived correlates of alcohol and substance abuse behaviors, such as the host of risk and protective factors thought to either increase the risk for offer protective benefits against the development of adolescent alcohol and other substance abuse problems. The proposed randomized clinical trial for adolescent problem drinking is designed to examine treatment outcomes for four intervention approaches, individual cognitive-behavioral therapy, family therapy, an integrative treatment approach that combines individual and family therapy interventions, and a skills-focused psycho-educational group intervention. Each of these treatment approaches has strong theoretical and empirical bases and suggests distinct sets of risk and protective factors. An evaluation of outcomes across the four conditions will provide a clearer understanding of which treatment approaches have the greatest benefit for the drinking adolescent, the drinker's parents and siblings, the family system functioning relative to the associated costs of drinker's parents and siblings, and the family system functioning relative to the associated costs of treatment. Moreover, by testing hypotheses linking specific risk and protective factors directly to theoretical treatment formulations, examining selected client-treatment matching variables, and examining therapy process in relation to outcome, the mechanism and action of factors associated with adolescent problem drinking and the change process can be explicated, enhancing the theoretical understanding of the problem and guiding the development of effective treatments.
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{
"pile_set_name": "NIH ExPorter"
}
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This proposal is a competitive renewal of R01 DK64832 previously titled "Neurocognitive effects of hypoglycemia in T1DM". That grant hypothesized that prior severe hypoglycemia would reduce memory and hippocampal volume in youth with type 1 diabetes mellitus (T1DM). In the process of addressing this relatively narrow question, we have collected a uniquely large developmental neuroimaging and cognitive dataset in youth with T1DM that now allows us to examine broader and more complex issues. In light of new data and hypotheses, we have renamed the grant "Glycemic control, brain structure and cognitive development in T1DM". We now are able to address whether there is a differential effect of severe hypoglycemia (Hypo) and chronic hyperglycemia (Hyper) on the developmental trajectories of brain regions and whether these structural effects are reflected in changes in cognitive function. In our analyses to date, we found that a retrospective history of severe Hypo in youth with T1DM was associated with reduced volume in the posterior temporal- parietal cortex and reduced memory skills. In contrast, a retrospective history of Hyper in these same youth was associated with reduced volume in medial occipital-parietal cortex and lower verbal intelligence. These results are consistent with growing evidence that exposure to glycemic extremes has permanent consequences for the structural and functional integrity of these cortical regions. However, these data have come from retrospective studies and so the direction of causality can only be hypothesized. To address this ambiguity, prospective data are greatly needed. Our prior grant enrolled and characterized a large sample of youth with T1DM and followed them for two years. We now have new preliminary prospective data that demonstrate altered developmental trajectories of gray and white matter in the brain related to Hyper exposure during a 2 year follow-up period. However, the low frequency of severe Hypo during this time did not allow us to test hypotheses about Hypo's effects on brain development. To capture a wider range of exposure and enhance our power to test hypotheses we propose to follow this uniquely characterized cohort for 3 more years to assess change in brain structure and cognitive function over a full 5 years of T1DM. In addition, on the basis of new preliminary data suggesting that exposure to Hyper affects white matter microstructural integrity (measured with diffusion tensor imaging or DTI) in addition to regional brain volume, we propose to add state- of-the-art DTI measures to complement our existing measures. Finally, in order to more conclusively determine whether there are any differences at baseline in T1DM, we will add a newly diagnosed cohort to our longitudinal study. This plan, combined with our neuroimaging expertise and well-characterized existing cohort, places us in a unique position to test strong hypotheses about how glycemic extremes, brain structural integrity and cognitive function are related in youth with T1DM. PUBLIC HEALTH RELEVANCE: The goal of this project is to help determine whether central nervous system structure and function should join the peripheral nervous system, retina and kidneys as systems at risk during development in T1DM. This knowledge would have significant clinical implications for the optimal care of youth with T1DM.
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{
"pile_set_name": "NIH ExPorter"
}
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We propose to develop synthetic methodology which would be useful in syntheses of chemotherapeutics and to investigate model reactions of important biological processes. In both areas the processes to be studied are based on previous discoveries of new and/or novel chemistry in our laboratories. The use of alpha-heteroatom dipole stabilized carbanions in a synthetic sequence which provides electrophilic substitution adjacent to the heteroatoms of alchohols, thiols, and amines via the metalated esters, thioesters, and amides will be investigated. This methodology should provide alpha-lithioalcohol, alpha-lithiothiol, and alpha-lithioamine synthetic equivalents. The role of dipole stabilized carbanions in enzymatic decarboxylations will be evaluated in model studies. Extension of the use of secondary and tertiary amides, which we have shown to be the most powerful activities for ortho metalation, in regiospecific syntheses substituted of heteroaromatic and alicyclic systems is to be studied. The use of heterophilic additions to give synthetic equivalent of electrophilic oxygen and nitrogen at the oxidation level of alcohols and amines will be investigated.
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{
"pile_set_name": "NIH ExPorter"
}
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To characterize the magnitude and duration of the catecholamine surge in preterm infants at birth and at time intervals until the second day of life.
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{
"pile_set_name": "NIH ExPorter"
}
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CD36 is a membrane scavenger receptor that recognizes several ligands including native and oxidized lipoproteins and long chain fatty acids. Research supported by this grant has resulted in the identification of CD36 as an important facilitator of long-chain fatty acid uptake by key metabolic tissues. In the last funding period we studied animal models with genetically altered CD36 levels to examine the molecular mechanims that mediate the interaction between the metabolisms of fatty acids and glucose and how this impacts susceptibility to insulin resistance. We explored the role of CD36 in cross adipose tissue where we showed that it influences PPARgamma activation and the secretion of leptin and adiponectin. Finally we documented the role of fatty acids and the transcription factor FoxO1 in regulation of CD36 membrane localization and function in muscle cells. This application follows up on our recent findings that complex processing of CD36 via palmitoylation and ubiquitination of residues in its carboxyl domain mediates its acute regulation by ligands (fatty acids and oxidized lipoproteins) or regulators (insulin and FoxO1). Our hypothesis is that this regulated processing influences sorting of the protein to the membrane and its cellular redistribution. We propose that ubiquitination of CD36 by its ligands fatty acids and OxLDL is a protective mechanism that limits excess uptake of these lipids via inducing CD36 degradation and dysfunction of this mechanism would lead to pathology. We propose to examine the mechanisms involved in regulation of CD36 processing and the implications with respect to fatty acid metabolism and insulin resistance. We will also explore how intracellular trafficking of CD36 influences lipid storage at the level of biogenesis and maturation of lipid droplet in adipocytes. We will test the hypothesis that adipose tissue CD36 exerts a protective effect with respect to pathophysiology due to positive energy balance by promoting activation of adipose PPARgamma and lipid storage which minimizes ectopic fat accumulation. The work proposed has potential clinical significance. In humans, polymorphisms in the CD36 gene are common and CD36 variants have been linked to dylipidemia, susceptibility to the metabolic syndrome and to cardiovascular disease. A better understanding of the molecular regulators of CD36 function in FA uptake and processing will help in designing better therapies that prevent or reverse dysfunctional FA metabolism and its deleterious consequences.
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{
"pile_set_name": "NIH ExPorter"
}
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The aim of the HERITAGE Family Study is to document the cardiovascular and metabolic responses to endurance training, and the contribution of genetic factors to the concomitant response of cardiovascular disease (CVD), and type 2 diabetes risk factors. In Phase 1 (1992-1997), 855 sedentary subjects from 218 families were recruited and 742 subjects (483 Whites from 99 families, 259 Blacks from 105 families) completed a standardized 20-week exercise-training program. During Phase 2 (1997-2001), a series of non-genetic studies on determinants of cardiorespiratory endurance, and CVD and type 2 diabetes risk factors in the sedentary state and in the response to training were undertaken. Genetic analyses focused on the determination of the heritability levels, and testing for paternal or maternal effects, major gene effects and segregation patterns. A panel of candidate genes was typed for association and linkage studies. A genome-wide scan was performed for the training response of cardiorespiratory endurance and CVD and type 2 diabetes risk factors. The proposed Phase 3 is organized around five specific aims. First, genetic epidemiology questions pertaining to training-related changes in major CVD risk factors will be investigated with special emphasis on Black and White differences. Second, the search for genes and mutations will continue utilizing four strategies: extension of the genome-wide scan including targeted dense SNPs mapping, extension of the skeletal muscle gene expression studies with SAGE, use of the AFLP technique and use of novel statistical methods such as multivariate linkage methods, subgroup analyses, and total genome-wide linkage tests. Third, the genetic and non-genetic determinants of insulin sensitivity, insulin secretion and glucose effectiveness in response to training will be investigated using LONGMOD, an extension of MINMOD currently in development to model longitudinal data more efficiently. Fourth, the nongenetic determinants of the targeted CVD risk factors and their responses to endurance training will be investigated, with emphasis on Black and White differences. Fifth, we will assess whether a closely supervised 20-week period of regular exercise had any long-term effects on habitual physical activity levels and health status. The findings from Phase 3 of the HERITAGE Family Study will provide unique information on the benefits of a physically active lifestyle and on the determinants of the high and low response phenotypes in Blacks and Whites.
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{
"pile_set_name": "NIH ExPorter"
}
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Infection with herps simplex type 1 induces expression of receptors for C3b on mammalian cells previously devoid of such receptors. We have shown that the isolated glycoprotein responsible for this activity (gC) is a potent modulator of complement-mediated cytolysis in vitro, acting by at least two mechanisms. We have also aided in the demonstration of relative complement resistance by cells infected with wild type HSV-1, as opposed to cells infected with gC-defective mutant strains. Future plans include direct binding studies of purified C3 fragments to HSV-1 gC and defined fragments thereof, as well as cells infected with other human herpesviruses. The role of gC as a blocker of infected cell interactions with cytotoxic lymphocytes will also be studied.
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{
"pile_set_name": "NIH ExPorter"
}
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The targeting of proteins across or into the endoplasmic reticulum (ER) is the first step in secretion and in the assembly of many membranes. With the exception of SRP, docking protein (SRP receptor) and the signal peptidase, little is known about the components involved or the requirements of this process. This is due, in large part, to the difficulty of further dissecting and reconstituting such a complex process. Augmenting a biochemical approach with a genetic one would allow further, and potentially more rapid, progress to be made in this area. Yeast cells, whose secretory pathway closely resembles that of higher eukaryotes, have the obvious advantage that they can be easily manipulated genetically. Recently targeting to the ER has been accomplished in a cell-free system derived from yeast. The objective of the research described in this proposal is the exploitation of yeast genetics, in combination with our existing biochemical expertise, to identify and characterize the components that mediate targeting to, and the translocation across, the membrane of the ER. We propose to refine the homologous yeast cell-free system to enable the isolation of cytosolic and membrane proteins involved in translocation. Important cytosolic components will be identified in a lysate-dependent post-translational assay. Biochemical and immunological methods will be employed to analyze the role of rough ER-specific proteins in translocation. Verification of the participation of these proteins in the secretory process will be accomplished in vivo by gene disruption techniques that are feasible in yeast. In parallel, we will select for new secretory mutants, defective in targeting and translocation, by the expression of a crucial cytoplasmic enzyme as a signal sequence-bearing chimera. Mutants produced in this way will then be characterized biochemically in the in vitro system.
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{
"pile_set_name": "NIH ExPorter"
}
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Atherosclerosis and periodontal disease are both chronic inflammatory diseases. Heliobacter pylori, Streptococcus sanguis, Phyromonas gingivalis (P. gingivalis) cytomegalovirus, and herpes simplex virus have been detected in atheroselerotic plaques, suggesting a link between bacterial and viral pathogens and atherogenesis. Epidemiologic studies have also suggested a link between periodontal infections and tooth loss with an increased risk for coronary artery disease. More recent studies have suggested that periodontal disease induced by P. gingivalis increases atherosclerotic lesion formation in hyperlipidemic mice. P. gingivalis induction of cyclooxygenase (COX) and lipoxygenase (LO) metabolism of arachidonic acid resulting in the production of inflammatory mediators, is suggested to play a role in both periodontal disease and atherosclerosis. Of the two COX isoforms, it is generally considered that the inducible COX-2 isoform synthesizes the prostanoids that are primarily responsible for generating inflammatory processes. COX-2 is expressed in diseased gingival tissue and atherosclerotic lesions. One of the prostanoids produced by COX-2 activation is prostaglandin E2 (PGE2) which is elevated in inflamed gingival tissues. Pharmacological COX-2 inhibitors reduce the size of atherosclerotic lesions in apolipoprotein E-/- (apoE) mice, suggesting that COX-2 plays a role in atherosclerotic lesion formation. Additionally, the use of bone marrow transplantation has demonstrated that the source of pro-atherogenic COX-2 is the infiltrating leukocytes. 12/15-LO is expressed in diseased gingival tissues and atherosclerotic lesions. Diseased gingival tissues produce increased concentrations of 12-hydroxyeicosatetraenoic acid (12-HETE) in vivo. To date little is known about the role of 12/15-LO in periodontal disease, 12/15-LO is localized to endothelial cells and macrophages in atherosclerofic lesions. Increased expression of 12/15-LO induces oxidation of lipoproteins and migration of leukocytes into the vascular wall. 12/15-LO deficiency markedly decreases atherosclerosis in hyperlipidemic mice. Moreover, 15-LO overexpression in the vascular wall induces atherosclerosis. Therefore, the focus of this grant will be to determine the role of COX-2 and 12/15-LO in P. gingivalis-induced alveolar bone loss and atherosclerosis. Our hypothesis is that P. gingivalis infection induces COX-2 and 12/15-LO expression and activation in the vascular wall thereby promoting the development and progression of atherogenesis. To test this hypothesis, the following specific aims are proposed: Specific Aim 1. Determine the role of COX-2 in P. gingivalis-induced periodontal disease and athcrosderosis. Specific Aim 2. Define the role of 12/15-lipoxygenase in P. gingivalis-induced periodontal disease and atherosclerosis. The proposed research will supply useful information about the relationship between periodontal disease and atheroselerosis. This research will provide insight into potential targets for the development of pharmacologic treatments influencing the development and progression of both of these diseases.
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{
"pile_set_name": "NIH ExPorter"
}
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