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ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 1 |
It is shown that by decreasing pH the fluorescence emission spectra are shifted toward the long wavelengths, with a broadening of the fluorescence band. The same effect can be obtained at constant pH by heating the protein solution. In order to analyze these phenomena, it is assumed that the fluorescence intensities at 355 nm and 328 nm reflect the proportion of the tryptophans which are exposed to the solvent, and buried, respectively.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 2 |
The plot of the ratio of the fluorescence intensities at these wavelengths versus pH or temperature leads to a titration curve showing an unmasking of tryptophans. The proportion of exposed tryptophans is measured by the dynamic fluorescence quenching technique and the data analyzed according to Lehrer. The plot of the fraction of exposed tryptophyls versus pH also shows the unmasking of these chromophores.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 3 |
Thermal perturbation of a solution of plaminogen at neutral pH induces a difference absorption spectrum whose amplitudes at the maxima are proportional to the number of exposed aromatic residues. The comparison with a solution of fully denatured plasminogen in 6 M guanidium chloride, where all the tryptophyls are exposed, shows that the percentage of exposure is equal to 59%.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 4 |
This number is significantly higher than the percentage found by the fluorescence quenching technique (20%), indicating that some tryptophyls are located in crevices, exposed to the solvent but not to the iodide. At acidic pH the absorption difference spectra induced by thermal perturbation are not classical, since they show an inversion and a new band between 300 nm and 305 nm.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 5 |
This band is mentioned in the literature as a minor band of tryptophan which appears when this chromophore is located in an asymmetric environment. On plotting the maximum amplitude of these spectra obtained at acidic pH versus temperature, we obtain a curve indicating that two types of antagonistic interactions are involved in the perturbation of the chromophores spectra.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 6 |
The spectrophotometric titration of plasminogen gives classical absorption difference spectra. By plotting the maximum amplitude at 292 nm versus pH, we obtain a titration curve with an apparent pK of 2.9 units. This pK is acidic which respect to the pK value of a normal carboxyl. This low value can be due to a positively charged group in the neighbourhood of a carboxyl, which interacts with one or more chromophores.
|
ddc50302-0508-423b-86a5-bffa0f5e0cf2
| 7 |
When the carboxyl becomes protonated, this positively charged group is free and available to perturb the environment of some chromophores...
|
834a05ad-caea-4e46-9725-09c5653c3066
| 0 |
Comparison of the metal-ion-promoted dephosphorylation of the 5'-triphosphates of adenosine, inosine, guanosine and cytidine by Mn2+, Ni2+ and Zn2+ in binary and ternary complexes. The dependence of the rate of dephosphorylation of ATP, ITP, GTP and CTP (= NTP), expressed as first-order rate constants (50 degrees C;
|
834a05ad-caea-4e46-9725-09c5653c3066
| 1 |
I = 0.1 M, NaClO4), on pH (2 to 10), in the absence and presence of Mn2+, Ni2+, and Zn2+, was investigated. The reaction is accelerated by Zn2+ and passes through a pH optimum at about 8 for the system Zn2+-ATP or 9 for Zn2+-ITP and Zn2+-GTP;
|
834a05ad-caea-4e46-9725-09c5653c3066
| 2 |
this is analogous to observations made earlier with the corresponding Cu2+ systems. By computing the pH dependence of the distribution of the several species present in these systems it is shown that the highest rates are observed in the pH regions where the concentration of Zn(ATP)2-, Zn(ITP-H)3-, or Zn(GTP-H)3- dominates.
|
834a05ad-caea-4e46-9725-09c5653c3066
| 3 |
By evaluating the pH dependence evidence is given that the attacking nucleophile is OH- or H2O for Zn (ATP)2- and H2O for Zn (ITP-H)3- or Zn(GTP-H)3-. For all these complexes metal-ion/nucleic-base interactions are known, leading to the formation of macrochelates.
|
834a05ad-caea-4e46-9725-09c5653c3066
| 4 |
These metal-ion/nucleic-base interactions are crucial for the observation of a metal-ion-promoted dephosphorylation; in agreement with this, and the small tendency of the cytosine moiety to coordinate, the CTP systems are rather stable towards dephosphorylation. It should be noted that these experimental results do not necessarily mean that the macrochelates usually described are the reactive complexes, but only that the active complex must be closely related to them (e.
|
834a05ad-caea-4e46-9725-09c5653c3066
| 5 |
g. isomers, etc). Although for the Ni2+ systems with ATP, ITP, and GTP, and for the Mn2+-ATP system a metal-ion/nucleic-base interaction is also known, these systems are not very sensitive to hydrolytic cleavage of the terminal P-O-P bond. The only known significant structural difference between the Ni2+-NTP or the Mn2+-ATP complexes and those of Cu2+ or Zn2+ is that Ni2+ Mn2+ coordinate to all three phsophate groups, whereas Cu2+ and Zn2+ involve only the beta and gamma ones.
|
834a05ad-caea-4e46-9725-09c5653c3066
| 6 |
This structure-reactivity relationship is rationalized by the suggestion that in the active species the metal ion should be coordinated to the alpha,beta-phosphate groups leaving the gamma-group open to nucleophilic attack. Obviously, an initial beta,gamma-coordination is suitable for a shift of the metal ion along the phosphate back-bone into the reactive alpha-beta-position, while for an alpha,beta,gamma-coordination only the less favorable removal of the coordinated gamma-group remains.
|
834a05ad-caea-4e46-9725-09c5653c3066
| 7 |
The metal-ion/nucleic-base interaction is considered as being important for achieving this reactive structure. The connection between trans-phosphorylation in vitro and in vivo is discussed. It is also shown that the formation of mixed-ligand or ternary complexes inhibits the dephosphorylation process. This is on the one hand of interest with regard to the transport of hydrolysis-sensitive phosphates in nature, while on the other it casts doubts on conclusions based on experiments carried out in the presence of buffers, because these contain weak bases and hence potential ligands.
|
d3189605-f003-43f3-9630-7b6196a2ad75
| 0 |
Rat-liver superoxide dismutase. Purification and age-related modifications. Cytoplasmic superoxide dismutase has been purified from livers of young (6 months) and old (27 months) rats. The enzyme purified from old animals shows an age-related reduction in the specific activity, accumulation of antigenically cross-reacting material and increased sensitivity to temperature.
|
d3189605-f003-43f3-9630-7b6196a2ad75
| 1 |
No differences were found in the molecular weight, electrophoretic mobility, antigenicity and Ki between enzymes purified from young and old rats. This is the first demonstration of age-related alterations in a purified form of a non-metabolic enzyme, which can be related to reduced activity. The possible role of this reduced activity in age-dependent deterioration of cellular functions is discussed.
|
1fb0b751-475d-4453-ac75-6198f36f7750
| 0 |
Effects of ouabain and hypoxia on the cardiac stimulation threshold in the dog (with special reference to changes in extra- and intracellular potassium concentrations). The influence on the cardiac stimulation threshold of changes in the myocardial intra/extracellular potassium ratio induced with ouabain and hypoxia was investigated in 9 dogs with total atrioventricular block. In spite of significant elevations of extracellular potassium and reductions of intracellular potassium significant changes in stimulation threshold were not seen. It is suggested that different experimental conditions are responsible for the great variations in the results of previous studies of this subject.
|
64efa465-2bf8-475a-88d4-f69217fd6899
| 0 |
The effect of fructose infusions on the oxygen transport system of human blood. In 9 healthy subjects the erythrocyte 2,3-diphosphoglycerate (2,3-DPG) concentration, which modifies the oxygen affinity of haemoglobin, decreased by more than 25 per cent within 60 minutes of the beginning of a fructose infusion (0.5
|
64efa465-2bf8-475a-88d4-f69217fd6899
| 1 |
g.kg body weight-1.h-1). In contrast erythrocyte adenosine triphosphate (ATP) concentration was unchanged. In spite of the diminished 2,3-DPG concentrations the oxygen affinity of whole blood actually measured remained unaltered. However, at the same time both the arterial and the venous blood pH had fallen by 0.05
|
64efa465-2bf8-475a-88d4-f69217fd6899
| 2 |
or more. In vitro experiments indicated that this fall of erythrocyte 2,3-DPG was not due to a direct effect of fructose on the intra-erythrocytic regulation of 2,3-DPG or to changes indirectly related to the intravenous administration of fructose in vivo, i.e. an increase of the blood lactate/pyruvate ratio or a decrease of plasma inorganic phosphate.
|
64efa465-2bf8-475a-88d4-f69217fd6899
| 3 |
It is suggested that two opposing effects on the oxygen transport system of blood are induced by fructose infusions: 1) a displacement of the oxygen dissociation curve to the right due to the Bohr effect 2) a virtually counterbalancing shift of the oxygen dissociation curve to the left due to decreased erythrocyte 2,3-DPG concentrations.
|
891e8367-2f5c-4bad-8337-c9bf0a8150f0
| 0 |
A comparison between a melanocyte-stimulating hormone inhibitory factor (MIF-I) and substances known to activate central dopamine receptors. The tripeptide, prolyl-leucyl glycine amide, a melanocyte-stimulating hormone inhibitory factor (MIF-I), which has been reported to be effective in improving symptoms of Parkinson's disease, has been compared with drugs known to activate dopamine receptors in rat and mouse brain.
|
891e8367-2f5c-4bad-8337-c9bf0a8150f0
| 1 |
Unlike apomorphine, amphetamine and amantadine it was incapable of producing sterotyped behaviour in the rat and unlike 1-dopa it was also ineffective in rats pretreated with the monoamineoxidase inhibitor mebanazine. Neither did it potentiate apomorphine nor amphetamine in this test. MIF-I did not antagonise chlorpromazine-induced loss of locomotor activity in mice, an effect which was antagonised by apomorphine, amphetamine and amantadine.
|
891e8367-2f5c-4bad-8337-c9bf0a8150f0
| 2 |
Chlorpromazine hypothermia in the mouse was antagonised by 1-dopa but not by MIF-I; similar findings were obtained in reserpine-pretreated mice. These results suggest that the reported beneficial effect of MIF-I in Parkinson's disease is unlikely to be due to an interaction with dopamine systems in the brain.
|
efd44f5e-da7b-4696-86b5-91724a050a15
| 0 |
Acute graft-versus-host reaction in mice. 3. Organ distribution of injected 51 chromium labeled lymphocytes. The distribution of labeled lymph node cells, causing an acute GvH reaction in lethally irradiated allogeneic recipients, was studied. Lymph node cells of C57BL mice were labeled with 51Cr and injected into lethally irradiated:
|
efd44f5e-da7b-4696-86b5-91724a050a15
| 1 |
a) C57BL mice, b) CBA mice, c) CBA mice sensitized to C57BL antigens prior to irradiation, d) CBA mice splenectomized before irradiation. Two more experimental situations were studied in which C57BL donors of lymph node cells were: e) presensitized to CBA antigens, or f) deprived of T-lymphocytes.
|
efd44f5e-da7b-4696-86b5-91724a050a15
| 2 |
The amount of radioactivity was determined in the whole body, blood, liver, spleen, subcutaneous lymph nodes, lungs, femora and kidneys of the irradiated recipient at regular intervals from the time of injection to the 120th hour after it. We found that living cells lodged predominantly in the spleen and the lymph nodes, while dead and dying cells accumulated in the liver.
|
efd44f5e-da7b-4696-86b5-91724a050a15
| 3 |
Other organs contained very small amounts of radioactivity. All the results point to the primary role of the spleen in the acute graft-versus-host reaction.
|
1dcd0b2e-e039-450a-b410-90862436242d
| 0 |
Mitigation of graft-versus-host disease in mice by treatment of donors with bacterial endotoxin. Treatment of DBA/2 (H-2d) mice with bacterial endotoxin prior to transplantation of their spleen and lymph node cells into immunosuppressed AKR (H-2k) mice prevented acute mortality from graft-versus-host (GVH) disease.
|
1dcd0b2e-e039-450a-b410-90862436242d
| 1 |
AKR mice that received immunocompetent cells from untreated DBA/2 mice had a median survival time (MST) of 13 days. In contrast, AKR mice that received immunocompetent cells from endotoxin-treated DBA/2 donors had an MST of 54 days. Endotoxin treatment of AKR recipients was not essential for preventing mortality from acute GVH disease.
|
1dcd0b2e-e039-450a-b410-90862436242d
| 2 |
Chimerism was proved by demonstrating that the lymphoid cells of long-term surviving AKR mice had the characteristics of DBA/2 lymphoid cells as measured by their response in mixed leukocyte culture (MLC) tests. Spleen cells from endotoxin-treated DBA/2 mice were able to stimulate, and to be stimulated by, AKR spleen cells in MLC assays.
|
1dcd0b2e-e039-450a-b410-90862436242d
| 3 |
Furthermore, spleen cells from endotoxin-treated DBA/2 mice did not suppress the responses of DBA/2 or AKR spleen cells in 'three-party' MLC tests.
|
618d9600-d31d-4f92-a431-fd8108bf6971
| 0 |
Influence of diurnal cycles on biochemical parameters of drug sensitivity: the pineal gland as a model. Diurnal cycles in physical parameters in the environment modulate biochemical and physiological circadian rhythms in experimental animals, including cycles in the sensitivity to external influences. Environmental lighting synchronizes cycles of indole metabolism and melatonin synthesis in the rat pineal gland by modulating the activity of postganglionic sympathetic nerves.
|
618d9600-d31d-4f92-a431-fd8108bf6971
| 1 |
As a consequence, the sensitivity of pineal N-acetyltransferase to stimulation by isoproterenol or by dibutyryl cyclic AMP varies diurnally. Also, the capacity of actinomycin D to inhibit this induction varies with circadian periodicity. The cycles in sensitivity to isoproterenol reflect cycles in the system that regulates cyclic AMP production, and include variation in the availability of specific B-adrenergic binding sites, and in the sensitivity of receptor-coupled adenylate cyclase to catecholamines.
|
618d9600-d31d-4f92-a431-fd8108bf6971
| 2 |
Further, a variation in the response to dibutyryl cyclic AMP indicates in addition the participation of intracellular controls in the regulation of the sensitivity of N-acetyltransferase to catecholamines. The varying sensitivity to actinomycin D suggests a changing requirement for the synthesis of RNA as a function of prior environmental lighting conditions.
|
618d9600-d31d-4f92-a431-fd8108bf6971
| 3 |
The basic nature of these sensitivity changes suggests that diurnal cycles of environmental lighting may similarly affect other systems.
|
b59ce70b-3464-42ac-b46f-ac130933c9a2
| 0 |
Nitrite, nitrosamines, and cancer. Carcinogenic N-nitroso compounds are formed from the reaction of naturally-occurring amines and nitrites that may be added to foods or produced by bacterial reduction of nitrate. N-Nitroso compounds can be produced during processing, storage and preparation of foods and in the mammalian stomach.
|
b59ce70b-3464-42ac-b46f-ac130933c9a2
| 1 |
Factors that influence the rates of nitrosation reactions include pH, temperature, catalysts, and inhibitors. Predictions of the extent of nitrosation are complicated by these factors and ultimately the amounts and types of N-nitroso compounds present must be determined by direct analysis. Methods for detection and estimation of volatile nitrosamines are available and low levels (parts per billion) have been found in some cured meat and fish products.
|
b59ce70b-3464-42ac-b46f-ac130933c9a2
| 2 |
General methods for detection of all N-nitroso compounds are not available yet, but are under development. Evaluation of the risk to human populations from these compounds is difficult in the absence of more comprehensive data on their environmental distribution.
|
64d77ae2-c6cc-4d7b-bae4-22ca9ecc8707
| 0 |
Hypothalamic inactivation of thyrotrophin-releasing hormone. Following the demonstration of peptidases in the rat hypothalamus which inactivate thyrotrophin-releasing hormone (TRH), a sensitive and specific radioimmunoassay for the releasing hormone was used to investigate the presence of similar peptidases in the rabbit hypothalamus. TRH was found to be rapidly inactivated by supernatant and particulate hypothalamic fractions, with higher peptidase activity in the supernatant than in the particulate fraction.
|
64d77ae2-c6cc-4d7b-bae4-22ca9ecc8707
| 1 |
An optimum pH of 7.3 within physiological limits was obtained for the enzymes in both the fractions examined. The results obtained confirm that the rabbit hypothalamus contains enzymes capable of inactivating TRH, and since it has been found that such peptidases interfere with studies on TRH biosynthesis, it is possible that the peptidases may play a part in controlling the releasing hormone's production.
|
64d77ae2-c6cc-4d7b-bae4-22ca9ecc8707
| 2 |
The specificity of the antiserum used in the radioimmunoassay has also suggested that the peptidases may cleave the C-terminal-ProNH2,-NH2 or both from the TRH molecule to cause inactivation.
|
4de3ce0d-44c5-4af4-a066-7f64e8136c80
| 0 |
Effect of cimetidine on 24-hour intragastric acidity in normal subjects. The effect of H2-receptor blockade on intragastric acidity was studied in nine normal males. The pH of their gastric contents was measured at hourly daytime and two hourly nighttime intervals for 48 hours. The subjects ate identical meals, drank identical volumes of fluid, and smoked the same number of cigarettes during the two study days.
|
4de3ce0d-44c5-4af4-a066-7f64e8136c80
| 1 |
Their physical activity was unrestricted in a ward environment. Blood cimetidine and plasma gastrin were measured in serial blood samples. The nine subjects were treated in random sequence with cimetidine 0-8-1-0 g on one day and placebo capsules on the other. The drug was given in four divided doses:
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4de3ce0d-44c5-4af4-a066-7f64e8136c80
| 2 |
four subjects received it before, and five after, the three main meals. All took the fourth dose at bedtime. Replicate studies in an additional subject given placebo on both study days showed good reproducibility (r=0-80, P less than 0-01). Cimetidine therapy decreased intragastric acidity in all nine subjects.
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4de3ce0d-44c5-4af4-a066-7f64e8136c80
| 3 |
The decrease was similar in the two groups taking the drug before or after meals, mean 24 h intragastric hydrogen ion activity being lowered by 70 and 72% respectively. Nocturnal anacidity was recorded in only two of 45 samples. Administration of cimetidine before meals produced earlier and higher drug blood levels than post-prandial medication, but when it was taken after food the blood levels were highest at the time when the buffer capacity of the food was waning.
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4de3ce0d-44c5-4af4-a066-7f64e8136c80
| 4 |
Blood concentrations of cimetidine exceeded the secretory IC50 level for most of the time between doses. The results show that cimetidine 0-8-1-0 g/day in four divided doses produces a striking and consistent decrease of intragastric acidity. Although variation in the timing of the dose in relation to meals did not affect the decrease of acidity, the absorption data suggest that patients should take the drug after meals.
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a80a14d0-bee6-4044-8898-35de8b3552a2
| 0 |
The effects of some factors on the growth and morphology of Naegleria sp. and three strains of the genus Acanthamoeba. The effects of various biophysical and chemical factors on the cytology of vegetative stages of Naegleria sp., Vitek strain, Acanthamoeba culbertsoni, Acanthamoeba castellanii, Neff strain and Acanthamoeba polyphaga, No.
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a80a14d0-bee6-4044-8898-35de8b3552a2
| 1 |
1289, were studied. The amoebae were cultured in a liquid medium under axenic conditions. The optimum temperature was 37 degrees C for pathogenic strains of Naegleria sp. and Acanthamoeba culbertsoni and 20 degrees C for A. castellanii. No changes were observed in the growth of A. polyphaga at the temperatures 20 degrees and 37 degrees C.
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a80a14d0-bee6-4044-8898-35de8b3552a2
| 2 |
The strains investigated grew at pH values of 5.6 to 7.7 using Soerensen's buffer. At the limit values the growth was inhibited and the morphology of cells was markedly changed. All of the four strains grew still at pH 8.4 kept by NaHCO3. A. polyphaga grew at partial anaerobiosis.
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a80a14d0-bee6-4044-8898-35de8b3552a2
| 3 |
The three tested strains of the genus Acanthamoeba grew in liquid axenic medium with 0.89% NaCl. The growth of Naegleria sp., Vitek was inhibited already at 0.2% concentration of this salt. The addition of 3 X 10(-2) m KCl to the culture medium had a harmful effect on the growth and morphology of three tested strains, except A.
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a80a14d0-bee6-4044-8898-35de8b3552a2
| 4 |
polyphaga. In the culture medium containing 2 X 10(-3) m CaCl2 the encystment of both pathogenic strains was stimulated. The cytological changes under experimental conditions were manifested by atypical movement of trophozoits and their intracellular structure.
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dafcf155-4c75-4076-ac67-2a39f815e8ae
| 0 |
[Potassium substitutes during tocolysis]. The level of serum potassium during tokolytic therapy with Partusisten and Isoptin decreases in the first 24 hours of therapy. This decrease is not due to an increase in renal potassium elimination. During tokolytic treatment the serum level of potassium returns to its normal value after 48 hours without potassium substitution.
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dafcf155-4c75-4076-ac67-2a39f815e8ae
| 1 |
While there is a decrease in serum potassium noticeable changes in electrocardiogram which are typial for hypopotassemia are observed. These changes disappear afer 48 hours of tokolytic treatment but never the less the initial serum potassium drop should be balanced by potassium substitution within these 48 hours.
|
384c357d-2803-4a20-b946-1d7e1057ef26
| 0 |
[Ambulatory therapy of trichomoniasis vaginalis. Clinical trial of a new Trichomonas-active azide substance]. Report on the results of the clinical trial of a new trichomonacide in ambulatory patients in a gynaecological practice. A report is given on a new drug for the treatment of vaginal trichomoniasis, which has been tried in 87 patients of a gynaecological practice under outpatient conditions.
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384c357d-2803-4a20-b946-1d7e1057ef26
| 1 |
The rate of failures was 5.7% (5 of 87 cases). The advantages over alternative preparations is to be seen in the short duration of treatment (24 hours at the most), and in the favourable tolerance in spite of high doses.
|
257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 0 |
Purification and properties of Klebsiella pneumoniae heat-stable enterotoxin. The enterotoxic material in cell-free growth preparations of Klebsiella pneumoniae serotype 5 was purified by sequential ultrafiltration and gel filtration (GF) procedures and the fractions were assayed for enterotoxic activity by determining their ability to induce in vivo net water secretion in the rat jejunum.
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257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 1 |
Whole-cell lysates were inactive. Anaerobic broth culture conditions yielded a 10-fold increase in toxin production over aerobic conditions. Enterotoxic activity was absent in the UM-10 retentate of the broth filtrate but present in both the retentate and filtrate of the UM-2 membrane. GF of the two UM-2 ultrafiltration fractions through a Sephadex G-25 column yielded an active eluate, whose potency was increased by 10- or 200-fold, in or adjacent to the void volume.
|
257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 2 |
When subsequently passed through a G-50 column, these pools eluted at a Kav of between 0.4 and 0.6 and were further increased in potency by two- or fivefold. A second equally potent fraction was also recovered in the void volume of the G-50 eluate of the UM-2 filtrate;
|
257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 3 |
this may represent a polymer. Progressive purification by GF was associated with an increased protein and decreased carbohydrate content of the most active fractions. The most active G-50 eluate of the UM-2 retentate had a minimal effective enterotoxic dose of 5 mug/ml and that of the filtrate was less than 0.1
|
257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 4 |
mug/ml. Heating the active GF eluates to 100 C for 30 min did not abolish enterotoxic activity and lowering the pH to 1 or incubation with either Pronase or trypsin had no effect on activity. These observations indicate that K. pneumoniae heat-stable enterotoxin is probably a single toxin with an apparent molecular weight in the range of 5,000.
|
257e1b7c-25aa-4368-9a7b-a9c5c7ce6b9c
| 5 |
The elution characteristics during GF as well as the chemical composition of the most purified enterotoxin fractions indicate that the toxin is not associated with endotoxin.
|
14ff06e2-1e75-449f-89ee-12b484371e70
| 0 |
Activity of two Streptococcus mutans bacteriocins in the presence of saliva, levan, and dextran. The extracellular dextrans produced from sucrose by Streptococcus mutans strains BHT and GS-5 did not prevent the synthesis or release of active bacteriocins by these two strains. In addition, several streptococci that were genetically sensitive to these bacteriocins, and that could synthesize a variety of extracellular dextrans and levans from sucrose, remained phenotypically sensitive when grown in the presence of sucrose.
|
14ff06e2-1e75-449f-89ee-12b484371e70
| 1 |
Bacteriocin activity was not altered by treatment with high-molecular-weight dextran or by human saliva. The bacteriocins produced by, and active against, S. mutans thus appear to be capable of acting in vivo and may play a role in regulating the bacterial ecology of the oral cavity.
|
285779ab-0e83-41fe-8edc-6f0604bf6a55
| 0 |
Cephacetrile, a new cephalosporin: in vitro, pharmacological and clinical evaluation. Cephacetrile, a parenteral cephalosporin, was evaluated for in vitro antibacterial activity, clinical pharmacology and effectiveness in the treatment of severe infections. The antibacterial activity against 187 isolates was determined by an agar-dilution technique. The MICs were 0.06
|
285779ab-0e83-41fe-8edc-6f0604bf6a55
| 1 |
to 0.5 mug/ml for Group A Streptococcus, D. pneumoniae, and Staph. aureus, 4-6 mug/ml for E. coli and Klebsiella-Enterobacter 8-32 mug/ml for Pr. mirabilis and more than 500 mug/ml for Ps. aeruginosa. A few strains of Klebsiella and E.
|
285779ab-0e83-41fe-8edc-6f0604bf6a55
| 2 |
coli had MICs of more than 125 mcg/ml. Serum levels after 0.5 and 1 g of i.m. cephacetrile were respectively 14.6 and 18.6 mug/ml after 1 hr, and 1.5 and 2.5 mug/ml after 6 hr. Serum levels after i.v. infusion of 0.5 and 1 g were respectively 16 and 25 mug/ml after 1 hr.
|
285779ab-0e83-41fe-8edc-6f0604bf6a55
| 3 |
, and 1 and 2 mug/ml after 6 hr. Urine levels after 0.5 and 1 g i.m. cephacetrile were respectively 500 and 650 mug/ml in the 0-3 hr period, and 250 and 300 mug/ml in the 3-6 hr period. Renal clearance was 166 +/- 5 ml/min/1.73
|
285779ab-0e83-41fe-8edc-6f0604bf6a55
| 4 |
m2; renal excretion was about 20% of the dose 6 hr after i.m. injection. Cephacetrile was well tolerated when administered i.m. with lidocaine. Mild phlebitis occurred sometimes after i.v. infusions. The clinical response, evaluated in 36 patients with severe systemic, respiratory and urinary infections, was good in all but two cases.
|
03c0abf9-0e29-435a-9e57-9164017f4e2d
| 0 |
Pituitary gonadotropin response to luteinizing hormone-releasing hormone (LH-RH) in males with azo- and oligospermia. Twenty-one males with azo- or oligospermia presenting with infertility and with no evidence of organic disease were studied with luteinizing hormone - releasing hormone (LH-RH). A pituitary luteinizing hormone (LH) and follicle stimulating hormone (FSH) response was present in all cases and was normal in the majority of the subjects.
|
03c0abf9-0e29-435a-9e57-9164017f4e2d
| 1 |
Serum testosterone and 17 beta estradiol levels were normal in all cases studied. No significant correlations were found between the gonadotropin estimations and sperm count, basal serum testosterone or testosterone response to human chorionic gonadotropin. It is concluded that LH-RH is of limited diagnostic use in the investigation of this group of patients with male infertility and provides no further insight into the pathogenesis of this condition.
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 0 |
Age at the menopause and onset of the climacteric in women of Martin District, Czechoslovkia. Statistical survey and some biological and social correlations. In this study, 6877 women were analysed whose ages ranged between 38 and 58 (born between 1909 and 1929) and who had had no artificial menopause. This is 88.04
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 1 |
% of the total female population in this actual period of life, living in Martin District in 1967. The mean age at the menopause was found, by status quo method, to be 51.21 years (standard deviation 4.4), and by the method of weighted arithmetical means, 48.81 years, (standard deviation 3.9
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 2 |
). The mean age at the onset of the climacteric, calculated by the same methods, was 47.55 years, or 46.74 years, respectively. The mean age at menarche was 14.6 years. The average birth-rate was 2.8. The mean period of fertility for the series as a whole was 36.6
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 3 |
years. Women with menstrual disturbances had their menopause about 1 year earlier. We have noted a similar tendency in nulliparas and primiparas. We could find no great difference in the age at menopause between those who had had an early or a late menarche. Menstrual disturbances also influenced the onset of the climacteric.
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 4 |
It was at least one year earlier than with regular menstruation. Age at menarche and parity had no effect on the age at the onset of climacteric. Women working in agriculture and housewives had their menopause a little later than mean age of the series, whereas manual workers and those in other occupational categories had their menopause and onset of the climacteric about 1 year earlier.
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980b92e4-28cb-402f-b4a0-0d3e7603f4d8
| 5 |
Furthermore, single women had their menopause about one year earlier than the married ones. Widows had their menopause twice so often as the married women and they got it very soon after the husbands's death.
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dee3270d-8dec-4f14-9cc1-c3c4bef29c9e
| 0 |
Fibrinolytic activity of the rat ovum, appearance during tubal passage and disappearance at implantation. Fertilized rat ova were histochemically examined for their fibrinolytic activity. Activity was found during tubal passage, which disappeared at implantation. Simultaneously the fibrinolytic activity of the endometrium disappeared at deciduation. These changes might be a prerequisite for implantation of the zygote.
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ae087697-78b3-4815-8c15-0033f88c1ea6
| 0 |
Juvenile diabetes and human sperm quality. Spermiological findings in 25 juvenile diabetics in the age range 16 to 22 years (average 18.5) have been compared with normal spermiological findings in 24 individuals of the same age (16 to 22 years, average 18.7). A drift to lower sperm values in the group of the juvenile diabetics became evident in all parameters observed. As concerns motility and morphology, the differences between the groups reached statistically significant values.
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f32957d6-eb59-4990-923b-f73fca4c3309
| 0 |
On round-headed human spermatozoa. In an infertile man and his only, likewise infertile, brother the sperm contained only round-headed spermatozoa. Electron microscopic examination of embedded ejaculate revealed a malformation, viz. absence of acrosomes in all the spermatozoa with consequent lack of normal development of the heads of the spermatozoa.
|
f32957d6-eb59-4990-923b-f73fca4c3309
| 1 |
Acrosomeless spermatozoa were also found in the testicular tubuli. No disturbance of the endocrine functions could be demonstrated. The blood cells were of normal male karyotype. Investigation of meiosis, on the other hand, showed rudimentary second division. Two other unrelated infertile men showed the same isolated disturbance in their spermiogram.
|
f32957d6-eb59-4990-923b-f73fca4c3309
| 2 |
Treatment with chlomiphene had no effect on the structure of the spermatozoa or on the infertility. The rare disorder, which seems to be a special syndrome, the first hitherto distinguishable among the various types of teratospermia, and its probable background are discussed.
|
52a04fbc-45a9-43a7-abd5-86151c98267c
| 0 |
Assessment of the therapeutic effect of epimestrol and epimestrol associated with clomiphene in female sterility. In 24 women with disturbances of ovulation treated for sterility with Epimestrol, ovulation was achieved in 3 patients but none of these became pregnant after therapy. Since it has been suggested that the association of Clomiphene with a weak estrogen might improve the pregnancy rate, we decided to administer Clomiphene associated with Epimestrol.
|
52a04fbc-45a9-43a7-abd5-86151c98267c
| 1 |
Using this combined therapy in 58 patients, 32 out of the 58 women ovulated and 17 conceived. The overall rate of pregnancy using the combined therapy was no better than that obtained when Clomiphene alone is administered. From this study it is concluded that: (1) Epimestrol is not an effective method for the induction of ovulation, and (2) addition of Epimestrol to Clomiphene is of no clinical benefit.
|
8c618770-e275-4fd9-9171-efab54f57d7f
| 0 |
Improvement of fertility and semen quality in men treated with a combination of anticongestive and antibiotic drugs. The effects of a combined therapy of antibiotics and antiinflammatory drugs was evaluated in 344 men referred to our clinic for treatment of infertility. Physical signs of congestion, usually not severe, were detected in 244 men.
|
8c618770-e275-4fd9-9171-efab54f57d7f
| 1 |
The treatment caused significant improvement in semen quality, especially in sperm concentration, morphology and motility. Forty percent of the wives became pregnant. There was a striking relationship between increase in morphologically normal spermatozoa and incidence of pregnancy. It is speculated that the therapy had its major effect at the level of the epididymis and/or testis.
|
40bb3449-52e2-41de-a9e3-ee27aefc8ec2
| 0 |
Genital organs. Auto and homotransplantation in forty dogs. Auto and homo transplantation of the uterus and ovaries was studied in 40 bitches divided into four groups. Group A served as a control. In group B the omentopexy technique of auto-transplantation was used. This method did not prove very rewarding and all 12 grafts were found to have degenerated and were non-functioning when relaparotomy was performed, 3 months after transplantation.
|
40bb3449-52e2-41de-a9e3-ee27aefc8ec2
| 1 |
In group C, auto transplantation with vascular anastomosis was performed in 12 dogs, yielding satisfactory results including one successful pregnancy and the delivery of 3 healthy puppies. In group D homotransplantation of the internal genital organs was performed in two sets of twin dogs. No immunosuppressive treatment was used.
|
40bb3449-52e2-41de-a9e3-ee27aefc8ec2
| 2 |
These grafts survived for a limited period as proved by the functional tests and X-ray examination but after 3 months were found to be necrotic and degenerated. Graft function and viability was established by: X-ray examination, cytology of vaginal smears, the effect of gonadotropins on the grafted ovaries and finally relaparotomy undertaken after 3 weeks and 3 months.
|
d9604b12-b413-4417-b18d-00660a33a8b4
| 0 |
Crossed immunoelectrophoresis of sperm antibodies in human serum and cervical mucus. Sperm agglutinating antibodies are purified from sera and cervical mucus of women with unexplained causes of infertility which were positive in the FD-test. Fractionation was performed by affinity-chromatography in a batch device and the sperm agglutinating activity controlled by the Franklin and Dukes test.
|
d9604b12-b413-4417-b18d-00660a33a8b4
| 1 |
This sperm antibody fraction was determined via crossed immunoelectrophoresis by migration into an anti-human serum containing gel. In all cases only one big peak resulted. The negative control serum and mucus samples demonstrated no precipitation peaks. By absorption studies it was shown that the sperm agglutinating antibodies in sera were IgM and in cervical mucus IgA.
|
d9604b12-b413-4417-b18d-00660a33a8b4
| 2 |
The concentration of IgA and IgM was determined by comparison with standard human IgA and IgM. Thus only one serum- and one cervical mucus antibody seems to be responsible for agglutination. The number of experiments, however, is still too small for general conclusions. This method is easily and quickly performed and can therefore be used as a routine method for the determination of sperm agglutinating antibodies.
|
d9604b12-b413-4417-b18d-00660a33a8b4
| 3 |
Its application for sperm-immobilizing or cytotoxic activity remains to be tested.
|
e7a1e597-fc32-4bcb-987a-e75de907c374
| 0 |
Microbiopsy of the fallopian tube as a method for clinical investigation of tubal function in infertility. Microbiopsy of the fimbrial end of the fallopian tube may prove to be a valuable method for investigating the tubal pick-up and transport mechanism in infertility patients. Counting of the percentage of ciliated cells on semithin sections shows that in normal fertile women a percentage of such cells is present that is higher than in abnormal conditions such as peritubal adhesions, ectopic pregnancy and amenorrhoea following prolonged progestogen treatment.
|
e7a1e597-fc32-4bcb-987a-e75de907c374
| 1 |
It is also suggested that ultrastructural examination of the biopsy may provide additional valuable information.
|
c90f8af0-8c6d-423d-99ab-975a721e5964
| 0 |
Improvement of sperm motility in patients with asthenozoospermia by kallikrein treatment. Parenteral and oral application of kallikrein (EC 3.4.21.8)--a kinin-releasing proteinase from porcine pancreatic tissue--significantly stimulates quantitative and qualitative sperm motility in subfertile males with semen criteria of asthenozoospermia. Improvement of sperm motility was found to exist for at least 3 months following termination of the 7 week duration kallikrein treatment. Additionally, a significant increase in the number of spermatozoa was observed 3 and 5 months after starting parenteral application of kallikrein.
|
be8e0f1b-1abc-4177-aecb-10e33a8ae58d
| 0 |
Oligozoospermia: a seven-year survey of the incidence, chromosomal aberrations, treatment and pregnancy rate. No sperm count should be regarded too low to consider extensive treatment in order to improve semen or to correct any possible abnormalities in femal partners. The infertile couple should be given devoted care and advice to improve their sexual relations and their psychological attitude towards the problem of infertility.
|
be8e0f1b-1abc-4177-aecb-10e33a8ae58d
| 1 |
A pregnancy rate of 51.9% where the husband's count was less than 10 million/ml, offers adequate support for this statement. In cases of mental trauma inflicted on patients by a verdict of inability to achieve parenthood--on people who have already suffered severe psychological shock and tension resulting from a period of infertility--discouragement lessens the already doubtful chances of achieving pregnancy.
|
be8e0f1b-1abc-4177-aecb-10e33a8ae58d
| 2 |
In no circumstance should oligozoospermic patients receive treatment for infertility unless a chromosomal analysis has been completed and found normal, since our rate of chromosomal anomalies (11.4%) in a group of oligozoospermic patients is considered to be too high.
|
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