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d5ce5bd9-706e-47a5-bfaa-a675c7484de4
| 0 |
Towards rational therapy with monoamine oxidase inhibitors. A rational approach to the use of monoamine oxidase inhibitors (MAOIs) is outlined. Patients suitable for treatment cannot be classified adequately using conventional diagnostic labels. They include those with primary symptoms of hypochondriasis, agoraphobia and social phobias, irritability, somatic anxiety and anergia;
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d5ce5bd9-706e-47a5-bfaa-a675c7484de4
| 1 |
those with primary depressed mood, guilt, ideas of reference and personality disorders seldom respond. There is great variation in the interval between the first administration of these drugs and clinical response, and this may account for the inconsistencies in published trials. The type of drug and its dose may affect rate of response, as may biochemical factors, including acetylator and monoamine oxidase status.
|
d5ce5bd9-706e-47a5-bfaa-a675c7484de4
| 2 |
To obtain maximum benefit, a course of therapy with MAOIs should last for several months.
|
dbf0bc3f-c75b-4da7-bcea-8e951a2e93a2
| 0 |
Urinary gamma-glutamyl transpeptidase, an indicator of renal ischaemic injury and homograft rejection. Gammaglutamyl transpeptidase is an enzyme primarily located in the brush border of the proximal convoluted tubules of the kidney. Its unique localisation in the renal cells most easily damaged by ischaemia and its ease of assay provides the rationale for its use in the measurement of renal ischaemic injury.
|
dbf0bc3f-c75b-4da7-bcea-8e951a2e93a2
| 1 |
Using a standard experimental animal model, canine urinary gamma-GT activity was shown to be increased up to 70-fold following 90 min of unilateral renal ischaemia and was significantly raised following only 5 min ischaemia. The urinary gamma-GT was used as a measure of ischaemic injury associated with renal transplantation in man and 20 consecutive patients undergoing kidney transplant were studied by daily 24-hour urinary gamma-GT estimations and excellent correlation was obtained between raised enzyme activity and the clinical diagnosis of transplant rejection.
|
59f149d3-ec1f-42b9-b05d-1b049143ca84
| 0 |
Neutrophil pyruvate kinase deficiency with recurrent staphylococcal infections: first reported case. A woman with an intracellular killing defect in the neutrophils had neutrophil pyruvate kinase deficiency. She had had recurrent staphylococcal infections throughout her life. The enzyme present was unstable and its kinetics were abnormal.
|
29d5995d-9c9a-4e7a-8483-f6e970ec7490
| 0 |
Tyrosine hydroxylase and dopamine-beta-hydroxylase: distribution in discrete areas of the rat limbic system. Tyrosine hydroxylase and dopamine-beta-hydroxylase have been measured in 34 discrete areas and nuclei of the limbic system of the rat. Both enzymes showed an uneven distribution in this system. The ratio between tyrosine hydroxylase and dopamine-beta-hydroxylase activities showed a significant correlation when compared with the ratio of dopamine and norepinephrine concentrations for the areas studied.
|
29d5995d-9c9a-4e7a-8483-f6e970ec7490
| 1 |
The results strongly suggest that dopaminergic terminals are present in discrete areas of the limbic cortex, and several septal and amygdaloid nuclei, and allow the precise localization of dopaminergic and noradrenergic areas in the limbic system.
|
f0ef541f-b34a-4ca2-a09d-209ae5cef5fb
| 0 |
Resolution, specificity and transphosphorylase activity of calcifying cartilage alkaline phosphatases. The phosphate releasing activity from calf scapula cartilage was resolved by DEAE-cellulose chromatography into two distinct phosphatase activities. The activity eluted first from the column (phosphatase I) was active towards a variety of phosphate esters and several linear oligo phosphates including sodium pyrophosphate, while the second phosphatase activity (phosphatase II) was active only towards simple phosphate esters.
|
f0ef541f-b34a-4ca2-a09d-209ae5cef5fb
| 1 |
Phosphatase I acted towards oligo phosphates in a stepwise fashion hydrolyzing one phosphate at a time. Both phosphatase are sialoproteins and can transfer phosphate from any of their substrates into other than water phosphate acceptor molecules such as glycerol. By several criteria, it can be concluded that the two phosphatases are different enzyme entities.
|
ea48f0ca-4500-4e4c-adfd-f61d91519520
| 0 |
Testosterone metabolism in male rat epiphysis. Using radioactive substrate, thin-layer chromatography and recrystallization methods as well as differential centrifugation, gel filtration and electrophoresis, testosterone metabolism was investigated in male rat epiphyseal growth plate. 5alpha-androstane 3alpha-17beta-diol was found to be a major metabolite in vitro;
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ea48f0ca-4500-4e4c-adfd-f61d91519520
| 1 |
lesser amounts of androstenedione and androstanedione, and a very small amount of 5alpha-dihydrotestosterone were also identified. Radioactivity was recovered in epiphyseal subcellular fractions 30 minutes following in vivo administration of tritiated 5alpha-dihydrotestosterone; within 2 hours radioactivity had fallen to essentially background level in all fractions but the cytosol.
|
ea48f0ca-4500-4e4c-adfd-f61d91519520
| 2 |
A testosterone binding protein could not be identified within epiphyseal cytosol.
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 0 |
Studies related to antitumor antibiotics. Part V. Reactions of mitomycin C with DNA examined by ethidium fluorescence assay. The cytotoxic action of the antitumor antibiotic mitomycin C occurs primarily at the level of DNA. Using highly sensitive fluorescence assays which depend on the enhancement of ethidium fluorescence only when it intercalates duplex regions of DNA, three aspects of mitomycin C action on DNA have been studied:
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 1 |
(a) cross-linking events, (b) alkylation without necessarily cross-linking, and (c) strand breakage. Cross-linking of DNA is determined by the return of fluorescence after a heat denaturation step at alkaline pH's. Under these conditions denatured DNA gives no fluorescence. The cross-linking was independently confirmed by S1-endonuclease (EC 3.1.4
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 2 |
.-) digestion. At relatively high concentrations of mitomycin the suppression of ethidium fluorescence enhancement was shown not to be due to depurination but rather to alkylation, as a result of losses in potential intercalation sites. A linear relationship exists between binding ratio for mitomycin and loss of fluorescence.
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 3 |
The proportional decrease in fluorescence with pH strongly suggests that the alkylation is due to the aziridine moiety of the antibiotic under these conditions. A parallel increase in the rate and overall efficiency of covalent cross-linking of DNA with lower pH suggests that the cross-linking event, to which the primary cytotoxic action has been linked, occurs sequentially with alkylation by aziridine and then by carbamate.
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 4 |
Mitomycin C, reduced chemically, was shown to induce single strand cleavage as well as monoaklylation and covalent cross-linking in PM2 covalently closed circular DNA. The inhibition of this cleavage by superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6), and by free radical scavengers suggests that the degradation of DNA observed to accompany the cytotoxic action of mitomycin C is largely due to the free radical O2.
|
b1384cbd-7b29-4d89-ac5c-84063967569a
| 5 |
In contrast to the behavior of the antibiotic streptonigrin, mitomycin C does not inactivate the protective enzymes superoxide dismutase or catalase. Lastly, mitomycin C is able to cross-link DNA in the absence of reduction at pH 4. This is consistent with the postulated cross-linking mechansims.
|
e3adc617-feb9-4b7c-8508-a68838072b3b
| 0 |
Acid proteases from species of Mucor. III. Interaction with concanavalin A and concanavalin A Sepharose. The reaction of Mucor miehei protease with concanavalin A was followed by a turbidimetric assay in the pH range 5-8. At pH 4.0, no turbidity developed but binding of the enzyme to concanavalin A could be demonstrated by gel filtration.
|
e3adc617-feb9-4b7c-8508-a68838072b3b
| 1 |
Two fractions of apparent molecular weight 65000 and 52000 were isolated, the 65000 molecular weight species apparently representing a protomer of concanavalin A (24000) bound to the enzyme. An analysis of the circular dichroism spectrum of this complex suggested that protomer binding results in a conformational change in the enzyme which is associated with a 30% increase in proteolytic activity.
|
e3adc617-feb9-4b7c-8508-a68838072b3b
| 2 |
At pH 6.0, the enzyme was strongly bound to columns of concanavalin A Sepharose but could be removed by including alpha-methyl D-glucoside and NaC1 in the elution buffer. Some column degradation occurred at room temperature but was not detectable at 4 degrees C where rapid elution of the enzyme resulted in a greater than 90% yield of highly active protein.
|
e3adc617-feb9-4b7c-8508-a68838072b3b
| 3 |
Periodate-oxidized Mucor miehei protease and Mucor renin did not react with concanavalin A and were not bound to the affinity column.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 0 |
Physical, chemical, and enzymatic studies on the major sucrase of honey bees (Apis mellifera). A sucrase from honey bees (Apis mellifera) which precipitates between ammonium sulfate saturations of 50 and 70% (5 mg protein per millilitre) and which makes up the major portion of the sucrases of honey bees was purified to homogeneity as shown by several criteria.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 1 |
A large part of the sucrase was found in the head while most of the rest was in the abdomen (a small amount was in the thorax). The enzyme precipitated between the same values of ammonium sulfate saturation as did the sucrase in honey and honey sucrase exhibited kinetics very similar to those of this enzyme.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 2 |
The enzyme was found to be a relatively nonspecific alpha-glucosidase and was shown to have transglucosidase activity. The production of glucose from sucrose was rectilinear when plotted by the Hofstee method at low substrate concentrations but decreased at high sucrose concentrations. The production of fructose was rectilinear throughout the concentration range used.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 3 |
The production of both glucose and rho-nitrophenol when rho nitrophenyl alpha-D-glucoside was the substrate was linear by the Hofstee plot. These effects were found to be due to transglucolysis and a mechanism of action is proposed. Amino acid and amino sugar analyses indicated that the sucrase was a glycoprotein.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 4 |
The molecular weight was found to be between 51000 and 82000 by three different methods and an so20.w value of 4.0 S was obtained. There was no evidence for subunit structure. Tests of the enzyme under various denaturation conditions did not reveal any unusual stabilities. The sucrase bound very tightly to a hydrophobic column.
|
7f1d6cdd-82d9-4fa5-b6f0-5abe4a48a083
| 5 |
Iodoacetic acid decreased the activity of the sucrase but a large concentration was needed to bring about a 50% activity loss. Reducing agents caused some activity declines. Diethyl pyrocarbonate activated the enzyme.
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 0 |
Studies on the formation by rat brain preparations of CDP-diglyceride from CTP and phosphatidic acids of varying fatty acid compositions. The enzyme, CTP:phosphatidate cytidylyltransferase (EC2.7.7.41) which catalyses formation of CDP-diglyceride from CTP and phosphatidic acid has been studied in rat brain preparations and other tissues.
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 1 |
Improvement, as judged by the higher tissue activities obtained, in the assay method for this enzyme was achieved through use of phosphatidic acids sonicated in buffer-detergent solution saturated with ether and containing bovine serum albumin and use of short incubation times which essentially provided a measure of initial rates.
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 2 |
The enzyme of rat brain microsomes yielded with 1,2-dioleolphosphatidic acid as substrate a pH optimum of 6.8 with maleate buffer and optimal concentrations of 60mM for MG2+, 6MM for CTP and 250 mug per 0.8 ml for phosphatidic acid. Enzyme activity was mainly located in the 90,000 X g fraction (microsomal) with small but significant activity in the 12,000 X g fraction.
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 3 |
Comparison of activities (nanomoles CTP incorporated per milligram protein per minute) amongst tissues showed the following order: brain, 1.87; liver, 1.32; lung, 1.19; small intestine, 1.00; kidney, 0.69; heart, 0.41; diaphragm, 0.07; skeletal muscle, 0.02. Examination of the effect of varying the fatty acid composition in the phosphatidic acids added exogenously gave the following order (activities in parentheses);
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 4 |
1-stearoyl-2-oleoyl- (5.58), 1-oleoyl-2-stearoyl- (5.37), 1,2-dioleoyl- (4.49) 1-palmitoyl-2-oleoyl-(3.85), 1-stearoyl-2-arachidonoyl-(3.31), 1-arachidonoyl-2-stearoyl-(3.16), 1,2-diarachidonoyl-(0.72), 1,2-dicaproyl-(0.67), 1,2-dipalmitoyl-(0.67
|
f0dd35f8-60d5-4069-8dda-bb0e8689718c
| 5 |
) and 1,2-distearoyl-(0.18). The single bis- and lysophosphatidic acids tested were inactive as substrates. Apart from a possible preference for one or more unsaturated fatty acids the transferase enzyme showed no selectivity in respect to the fatty acid distribution of phosphatidic acids.
|
d77d4076-7991-4ef7-b01a-46b4b5b69c5c
| 0 |
Effect of metiamide on acid secretion from isolated kitten fundic mucosa. Isolated kitten fundic mucosa demonstrates low rates of spontaneous acid secretion in vitro when bathed in Krebs-Henseleit solution, and responds consistently to histamine, pentagastrin, and acetylcholine placed in the bath. High rates of spontaneous secretion or secretion in response to histamine and pentagastrin were significantly inhibited by addition of metiamide (5 X 10(-3) M); but mucosa stimulated by constant addition of acetylcholine chloride (10(-4) M) was not inhibited by metiamide at the same concentration.
|
248246c9-3c6d-4744-ac77-296313807efa
| 0 |
Myoplasmic impedance of the barnacle muscle fiber. Myoplasmic impedance was measured on a barnacle (Balanus nubilus) single muscle fiber that was placed in a cylindrical cavity to limit the volume and prevent the hydration of the myoplasm. At both ends of the cavity, the myoplasm was in direct contact with an electrolyte solution.
|
248246c9-3c6d-4744-ac77-296313807efa
| 1 |
When equilibrium with the external medium was reached, the myoplasmic impedance was measured at 10 degrees C with an impedance bridge at 1000 Hz. The results indicated that the myoplasmic impedance of the muscle fiber is mainly resistive. Treating the myoplasm as a suspension of small conductive particles, we deduced the specific conductivity of the contractile filaments kf and their volume fraction rho (kf = 2.78
|
248246c9-3c6d-4744-ac77-296313807efa
| 2 |
X 10(-3) omega-1cm-1, and rho = 0.48). The experimental technique permits an estimate of the specific myoplasmic conductivity in vivo (6.27 X 10(-3) omega-1cm-1). Finally, a decrease in the pH of the external solution from 10.1 to 4.0 lowered the myoplasmic conductivity by 16%.
|
248246c9-3c6d-4744-ac77-296313807efa
| 3 |
This may be considered as indirect evidence that the conductivity of the contractile filaments is associated with the protein counter-ions, since Hinke et al. (1973. Ann. N.Y. Acad. Sci. 204, 274-296.) reported evidence that a lowering of pH decreases the number of counter-ions.
|
2dd37e0a-6594-4e14-92ea-355ed3cf00e6
| 0 |
Pulmonary edema and ascorbic acid loss. Loss of ascorbic acid from lung and pulmonary edema were produced in mice by intravenous injection of either adrenaline or noradrenaline (5 mumol/kg). While adrenalectomy performed before noradrenaline administration reduced the degree of pulmonary edema, a prior dose of hexamethonium accentuated this effect.
|
2dd37e0a-6594-4e14-92ea-355ed3cf00e6
| 1 |
Given alone, hexamethonium caused both loss of ascorbic acid and pulmonary edema. The results show that although endogenous catecholamines can potentiate the pulmonary edema produced by either adrenaline or noradrenaline, they play no specific role in the ascorbic acid loss. The evidence suggests that lung ascorbic acid levels are decreased following the development of pulmonary edema, irrespective of how it was caused.
|
2c3559af-e663-467b-9a88-bdf3f611445e
| 0 |
Development of amino acid uptake activity in Neurospora. During the germination and growth of Neurospora conidia, amino acid permease systems I (neutral) and II (general) increase in specific activity. System III (basic) decreases in specific activity with the onset of germination. System I shows two peaks of activity during the logarithmic phase of growth.
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2c3559af-e663-467b-9a88-bdf3f611445e
| 1 |
One peak occurs at 6 h, the other at 12 h of growth. Both peaks are abolished in the mtr mutant. Both peaks have a Km for phenylalanine of 40 muM. The peaks of system I activity appear to correlate with morphological changes.
|
691d8c4e-51bd-4c2c-b9e6-583674df7827
| 0 |
Production, purification and characterization of thermomycolase, the extracellular serine protease of the thermophilic fungus Malbranchea pulchella var. sulfurea. The thermophilic fungus Malbranchea pulchella produces a single extracellular, alkaline, serine protease when grown at 45 degrees C, on 2% casein as sole carbon source. The growth-associated production of protease in submerged cultures was inhibited by addition of glucose, amino acids, or yeast extract.
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691d8c4e-51bd-4c2c-b9e6-583674df7827
| 1 |
A simple four-step purification which yields homogeneous protease in 78% yield is described. The protease has an isoelectric point of 6.0, a pH optimum of 8.5, and is completely inhibited by serine protease inhibitors. A specificity study with small synthetic ester substrates indicated that the protease preferentially hydrolyzed bonds situated on the carboxyl side of aromatic or apolar amino acid residues which are not beta-branched, positively charged or of the D configuration.
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691d8c4e-51bd-4c2c-b9e6-583674df7827
| 2 |
Peptidase substrates and others such as N-acetyl-L-tyrosine-ethyl ester were not hydrolyzed. The protease was stable over a broad range of pH (6.5-9.5 at 30 degrees C, 20 h), and was particularly thermostable (t1/2 = 110 min at 73 degrees C, pH 7.4
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691d8c4e-51bd-4c2c-b9e6-583674df7827
| 3 |
) in the presence of Ca2+ (10 mM). Macromolecules and Ca2+ also provide protection against the significant autolysis which occurs at pure protease concentrations greater than 0.01 mg/mo, as well as against surface denaturation which is enhanced by the presence of a silicone antifoam agent. Hence the stability of protease in submerged cultures is rationalized.
|
1fd99985-2814-453a-95ed-6a67ae61ffb8
| 0 |
Biosynthesis of chloramphenicol in Streptomyces sp. 3022a. Identification of p-amino-L-phenylalanine as a product from the action of arylamine synthetase on chorismic acid. Products obtained from the action of arylamine synthetase on [G-14C]chorismic acid were fractionated by gel filtration and ion exchange column chromatography to yield a partially purified radioactive component with an arylamine function.
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1fd99985-2814-453a-95ed-6a67ae61ffb8
| 1 |
From its ultraviolet absorption spectrum and thin-layer chromatographic behaviour the product was considered to be p-aminophenylalanine and the identification was confirmed by co-crystallization with an authentic specimen. Specific deamination of the product with L-amino-acid oxidase indicated that it was the L-epimer. These results strengthen previous evidence that arylamine synthetase is at a branch point in the shikimic acid pathway, specifically diverting intermediates to the synthesis of chloramphenicol.
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fbb82c4f-91b2-4384-93fc-bbb870d0855d
| 0 |
Uptake and efflux of succinic acid by uninduced mycelium of Claviceps purpurea. Claviceps purpurea PRL 1980 grew on partially dissociated succinic acid (pH 4) but not on fully dissociated succinic acid (pH 7.2). Myeclium suspended in 42 mM solution of partially ionized succinic acid (pH 4; 60.1
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fbb82c4f-91b2-4384-93fc-bbb870d0855d
| 1 |
% nonionized, 39% monoanion, and 0.9% dianion, K+ salt) over a period of 25 min accumulated more succinic acid carbon than mycelium suspended in highly ionized solution (pH 6.8; 0.01% nonionized, 4.8% monoanion, and 95% dianion). The greater accumulation from partially ionized solution was not attributable solely to metabolism of succinic acid nor to the lower external concentration of potassium ion.
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fbb82c4f-91b2-4384-93fc-bbb870d0855d
| 2 |
Rate of uptake by sodium azide and iodoacetate-treated mycelium was proportional to external concentration at least up to 200 mumol/ml. External potassium or sodium ion was not required for uptake by inhibited or uninhibited mycelium and external sodium ion and glucose did not allow concentration of succinic acid.
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fbb82c4f-91b2-4384-93fc-bbb870d0855d
| 3 |
The internal concentrations of succinic acid carbon expressed as succinic acid in cell water were about the same as the external concentrations. Uptake was not appreciably affected by extent of ionization of external succinic acid but accumulation was markedly affected. A plot of accumulated succinic acid carbon against external pH produced a bimodal curve with the two maxima corresponding to the maximal concentrations of nonionized and monoanion succinic acid.
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fbb82c4f-91b2-4384-93fc-bbb870d0855d
| 4 |
The bimodal curve probably results from overlapping of two separate curves; the nonionized form accumulating efficiently because of one interaction with the cell and the monoanion form accumulating efficiently because of another interaction. Uptake from concentrated solution is by diffusion and efflux is rapid but not complete. Efflux is not retarded by presence of phosphate in the external solution.
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b1a6c774-050d-458d-af3c-2375bd332b2e
| 0 |
Characterization of a nitrogen-fixing bacterial strain from the roots of Digitaria sanguinalis. Rates of nitrogen fixation of 3 to 10 g of N2 fixed per hectare per day were associated with root systems of Digitaria sanguinalis. A Gram-negative motile aerobic bacterial strain that was capable of N2 fixation was isolated from a washed root sample of one of these plants.
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b1a6c774-050d-458d-af3c-2375bd332b2e
| 1 |
Optimal growth and N2 fixation occurred at a pH of about 6.5, a temperature of 30-37 degrees C, and at a pO2 of about 0.01 atm. Increased rates of N2 fixation resulted when this strain was grown in mixed cultures with aerobic or facultative bacteria. Observations of cellular and cultural morphology and results of biochemical and physiological studies indicate that the isolate may be related to the Azotobacteraceae but that it is not identical with any of the members of this family.
|
b1a6c774-050d-458d-af3c-2375bd332b2e
| 2 |
The importance of N2 fixation by this isolate in nature is unknown.
|
e70dafec-46f1-4549-aa96-018d921682ca
| 0 |
Beta-glucanases in the yeast Cryptococcus albidus var. aerius. Production and separation of beta-glucanases in asynchronous cultures. beta-Glucanases were detected in cell-free extracts of the yeast Cryptococcus albidus var. aerius when grown on glucose as the sole carbon source. The production of beta-glucanases was followed in log-phase cells and stationary-phase cells;
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e70dafec-46f1-4549-aa96-018d921682ca
| 1 |
the maximal production of beta-(1 leads to 3) and beta-(1 leads to 6) glucanases takes place respectively in log-phase and stationary-phase cells. The results show that there are marked differences in the elution profiles on Sephadex G-50 of fractions containing beta-glucanase from cells grown for 12, 24, 48, 72, and 96 h.
|
e70dafec-46f1-4549-aa96-018d921682ca
| 2 |
The possibility either of replacement changes in fractions containing beta-glucanase activity or of a different synthesis of each beta-glucanase during the growth of the yeast is discussed. The results suggest that all fractions containing beta-glucanases hydrolyze both beta-(1 leads to 3) and beta-(1 leads to 6) linkages.
|
e70dafec-46f1-4549-aa96-018d921682ca
| 3 |
Evidence in support of the conclusion that a low molecular form of beta-glucanase has a molecular weight of 2100 +/- 100 is also shown.
|
1e25a652-7faf-48d0-8259-fcd70dabe9f4
| 0 |
Temperature-pH effect upon germination of bacterial spores. Using several kinds of criteria for the germination of bacterial spores, germination-pH curves were drawn for Bacillus subtilis spores observed at different temperatures. The experiments revealed that optimum pH for spore germination was markedly changed by changing the incubation temperature; the optimum pH for germination was 7.4 at 37 degrees C and 5.4 at 10 degrees C. A possible mechanism involved in this phenomenon is discussed.
|
8227761d-a608-43a5-87ed-78404744806d
| 0 |
Effect of variou cultural conditions on the fatty acid and lipid composition of Choanephora cucurbitarum. The fatty acid composition of the total and polar lipid fractions of Choanephora cucurbitarum grown under different cultural conditions were analyzed by thin-layer and gas-liquid chromatography. It was observed that temperature, age, pH, and light influenced the degree of unsaturation, this being due mainly to changes in the gamma-linolenic acid concentration.
|
8227761d-a608-43a5-87ed-78404744806d
| 1 |
The conditions used in this study did not alter the qualitative profile of fatty acids normally present in the organism. Neither did these conditions stimulate the production of further long-chain fatty acids (C20-C26) beyond gamma-linolenic acid (C18:3) as reported earlier using growth media containing glutamic acid.
|
8227761d-a608-43a5-87ed-78404744806d
| 2 |
The fatty acid pattern of lipid fractions though the same qualitatively, differed quantitatively. The polar lipid fractions, phosphatidyl choline, phosphatidyl ethanolamine, and diphosphatidyl glycerol showed an appreciable variation in gamma-linolenic acid content under different cultural conditions. The degree of unsaturation of the various lipid fractions decreased with increases in temperature, light intensity, and pH, but within each treatment the same pattern of decreasing degree of unsaturation with increasing age was observed.
|
8227761d-a608-43a5-87ed-78404744806d
| 3 |
The significance of these observations is discussed.
|
56a060dd-5341-46f4-bdd9-e19e4e8493d5
| 0 |
Superficial cell-wall layers on Spirillum "Ordal" and their in vitro reassembly. The cell envelope of Sporillum sp. strain "Ordal" (possibly a variety of S. anulus) demonstrated multiple superficial wall layers which were diverse in their macromolecular arrays. Negative staining and freeze-etching techniques revealed an outer hexagonally packed layer and an inner tetragonally packed layer.
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56a060dd-5341-46f4-bdd9-e19e4e8493d5
| 1 |
However, both thin sections and freeze-etched cleavages of the wall showed that each of these regular structures rested upon a backing layer, and that there was a delicate amorphous layer overlying the outer hexagonal array. Rotary integration, optical deffraction, and reconstruction of image were used to clarify measurements of each array and to verify the validity of a diagrammatic model of the outer hexagonal system.
|
56a060dd-5341-46f4-bdd9-e19e4e8493d5
| 2 |
The integrity of these layers required suitable cations (Ca2+ appeared essential) and pH (pH less than or equal to 4.6 dissociated most superficial layers). These observations aided in the development of a low-pH cationic-substitution technique, in which Na+ replaced essential Ca2+, for extraction of the layers from the cell surface.
|
56a060dd-5341-46f4-bdd9-e19e4e8493d5
| 3 |
Dialysis to remove Na+ and restoration of Ca2+ initiated in vitro reassembly of the superficial layer components until regularly structured assembly products were formed.
|
fbcf3c80-a655-4507-a7ac-d48f9a74da94
| 0 |
Premature labour. Prematurity is by far the commonest cause of neonatal morbidity and mortality. The management of premature labour is empirical because little is understood about the mechanism of labour. Effective uterine relaxant drugs have an important, albeit minor role. Phototherapy has reduced the complications of neonatal hyperbilirubinemia, and the beneficial effect of antepartum corticosteroid therapy in minimizing the risk of respiratory distress syndrome is now convincing.
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fbcf3c80-a655-4507-a7ac-d48f9a74da94
| 1 |
Prophylactic antibiotic therapy in premature rupture of the membranes does not alter perinatal mortality, although postpartum maternal morbidity is reduced. The introduction of neonatal intensive care units has improved the survival rate of premature infants. Sound clinical judgement remains the mainstay in the management of premature labour.
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ebd327ad-39bb-4e28-ba18-e581363c209b
| 0 |
Liver metastases found by follow-up of patients operated on for colorectal cancer. One hundred and twenty-six patients earlier operated on for colorectal cancer were followed-up once yearly with serum screening tests. The activities of alkaline phosphatase (AP) and gammaglutamyltranspeptidase (GT) were recorded. 58 patients had positive tests.
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ebd327ad-39bb-4e28-ba18-e581363c209b
| 1 |
The majority of the patients with liver metastases (20/21) was possible to encircle with these simple serum tests. 38 of the 58 "screening positive patients" were further investigated with celiac angiography and/or liver scintigraphy and liver metastases were very suspect in 29 of these patients.
|
ebd327ad-39bb-4e28-ba18-e581363c209b
| 2 |
18 of them were laparotomized and the suspicion was verified in 8.7 of these patients could be subjected to surgery against their liver tumours and 2 of them have then survived more than 2 years. The authors suggest a follow-up system with shorter interval between the examinations.
|
3dbf7e50-fa74-4b94-8680-26e08939dfd2
| 0 |
Carcinoembryonic antigen and phosphohexose isomerase, gammaglutamyl transpeptidase and lactate dehydorgenase levels in patients with and without liver metastases. Plasma carcinoembryonic antigen (CEA) and serum enzyme levels of phosphohexose isomerase (PHI), gamma-glutamyl transpeptidase (psi-GTP), and lactate dehydrogenase (LDH) were measured in 147 patients with malignancy. Levels were higher in patients (particularly with G.
|
3dbf7e50-fa74-4b94-8680-26e08939dfd2
| 1 |
I., breast and lung cancers) than in normals or in patients with cancer in clinical remission. Elevations of CEA and of all three enzymes in blood were most frequent in patients with hepatic metastases. CEA elevations correlated directly with PHI levels. Seventy-eight percent of patients with metastatic G.
|
3dbf7e50-fa74-4b94-8680-26e08939dfd2
| 2 |
I. cancer could be identified by CEA (greater than 5 ng/ml) alone, as well as 38% with breast cancer and 85% with lung cancer; but only 17% of other cancers could be identified by CEA alone. CEA or one or more enzymes was elevated in 64% of metastatic breast cancer patients, 92% of lung cancer and 41% of other cancers, but enzyme measurement did not increase identification of G.
|
3dbf7e50-fa74-4b94-8680-26e08939dfd2
| 3 |
I. cancer over that achieved by CEA alone. These findings suggest that circulating levels of CEA, PHI, psi-GTP and LDH may reflect a direct contribution from the malignant tissue and/or liver malfunction secondary to liver replacement.
|
75def1fb-46bb-49e6-8db2-2d4c7260731b
| 0 |
Controlled environment culture of bone marrow explants from human myeloma. Bone marrow biopsy specimens from patients with myeloma were cultured in either 1 of 2 thin-film culture systems, a controlled environment steady state system or a rocker tube configuration of the system, for periods up to 42 days.
|
75def1fb-46bb-49e6-8db2-2d4c7260731b
| 1 |
Both functional and morphological characteristics of the myeloma cells were well-maintained in these systems. Cytocentrifuge preparations of the culture media disclosed hematopoietic cells that included from 5% to almost 100% plasma cells. Histological examination of the cultured specimens disclosed infiltration of the marrow with myeloma cells. Myeloma proteins were released at a steady rate throughout the period of culture after the 1st 4 days.
|
75def1fb-46bb-49e6-8db2-2d4c7260731b
| 2 |
Bone-resorbing activity was demonstrated in the culture media in 7 of 9 myeloma culture media and was well maintained, particularly during the 1st week of culture. This activity was associated with severe osteolytic lesions in the donor patient and marked infiltration of the cultured specimen by myeloma cells.
|
75def1fb-46bb-49e6-8db2-2d4c7260731b
| 3 |
The potential use of these organ culture systems for the further definitive identification of the factor responsible for bone destruction in myeloma is discussed.
|
fadddf0d-90c7-42aa-b28c-8d0f62a3b610
| 0 |
Binding of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea to L1210 cell nuclear proteins. The binding of 1-(2-chloroethyl)-3-(cyclohexyl)-1-nitrosourea (CCNU) to the proteins of the L1210 cell nucleus has been studied using both [cyclohexyl-14C]CCNU and [chloroethyl-14C]CCNU. Most of the bound [cyclohexyl-14C] moiety of CCNU was found to exist in a form that was stable in acid solution but labile and dialyzable in alkaline solution.
|
fadddf0d-90c7-42aa-b28c-8d0f62a3b610
| 1 |
A small amount of the cyclohexyl moiety was bound to histones in a stable, nondialyzable form. The drug/protein ratio for the H1 histone was about 0.01 to 0.02 mole/mole. No binding of the cyclohexyl group to acidic proteins or of the chloroethyl group to either histones or acidic proteins was observed.
|
fadddf0d-90c7-42aa-b28c-8d0f62a3b610
| 2 |
Thus, the interaction of CCNU with the proteins of the cell nucleus can be defined in terms of the modification of histones by the cyclohexyl moiety.
|
1659a5c0-fd79-40e7-82fc-59b45c711915
| 0 |
31P nuclear magnetic resonance-pH titrations of myo-inositol hexaphosphate. With the use of 31P n.m.r. spectroscopy, the separate pKa values of each of the six phosphoric monoester groups of myo-inositol hexaphosphate were determined. The range of hydrogen-ion concentrations covered extended from that required for the phosphonium salts to that for the full dodecyl anion, and the determinations were carried out in the presence of sodium and tetrabutylammonium cations.
|
1659a5c0-fd79-40e7-82fc-59b45c711915
| 1 |
The pKa for each phosphate grouping in the transition from the free acid forms of each group to the monoanion form of each group was determined to be: 1.1, C-2; 1.5, C-1 and C-3; 2.1, C-4 and C-6; and 1.7, C-5.
|
1659a5c0-fd79-40e7-82fc-59b45c711915
| 2 |
In the mono- to di-anion transition, the pKa values were: 6.85, C-2; 7.60, C-5; 5.70 and 12.0, C-1 and C-3; and 10.0, C-4 and C-6. These data and the appearance of the 31P hexaphosphate n.m.r.
|
1659a5c0-fd79-40e7-82fc-59b45c711915
| 3 |
multiplet are discussed in terms of conformations of myo-inositol hexaphosphate.
|
0eeba8b8-a1b9-4ee5-b516-1e56132591fb
| 0 |
Age dependence of the number of the stem cells in haemopoietic tissues of rats. The number and concentration of haemopoietic stem cells in the femoral bone marrow and spleen of Wistar rats of different ages were investigated. Stem cells were assayed by the spleen colony technique in irradiated rat recipients.
|
0eeba8b8-a1b9-4ee5-b516-1e56132591fb
| 1 |
The ability of the recipient spleen to harvest transplanted tissue as a macroscopic colony was found to be dependent on the recipient's age. Changes with senescence were observed also in the concentration and the size of the stem cell compartment both in the marrow and spleen. No differences were demonstrated in the seeding of transplanted colony-forming units into the spleen of recipients of 1 and 4 months of age.
|
0eeba8b8-a1b9-4ee5-b516-1e56132591fb
| 2 |
A rats-mice strain difference in the effect of senescence on the haemopoietic stem cells is discussed.
|
fd2e36e3-faa7-4887-8177-a515fd981f28
| 0 |
Kinetics of haemopoietic recovery in endotoxin-treated mice. Kinetics of mouse spleen colony forming units were studied after intra-peritoneal injection of 1 mug/blody weight bacterial endotoxin S. typhosa. When these mice were used as unirradiated and sublethally irradiated donors, it was possible to study the effect of the endotoxin injection upon the cells.
|
fd2e36e3-faa7-4887-8177-a515fd981f28
| 1 |
Use of the treated mice as irradiated recipients of normal cells gave information about the host effect. In treated unirradiated mice, the total nucleated cell and the CFU counts were disturbed, and 2 days later a large fraction of the CFU were found in the DNA synthesis (S) phase.
|
fd2e36e3-faa7-4887-8177-a515fd981f28
| 2 |
This meant that injection of endotoxin generated factors affecting the kinetics of the CFU and triggering the resting CFU into the proliferative cycle. If then the mice were given supralethal irradiation and used as recipients of normal bone marrow cells, more CFU seeded to the spleen as compared to normal recipients;
|
fd2e36e3-faa7-4887-8177-a515fd981f28
| 3 |
but the dip and the growth rate of the CFU were not changed. Hence the endotoxin-generated factors had been eliminated in 2 days. A total body sublethal irradiation by 400 rad X-ray 2 days after endotoxin injection reduced the post-irradiation dip in the recovery curve of the CFU, indicating that though the factors affecting the cell kinetics had been eliminated, the cycling CFU behaved like a growing population.
|
fd2e36e3-faa7-4887-8177-a515fd981f28
| 4 |
During the first week, the growth rate of the CFU remained the same as in control irradiated mice. The growth rate of the spleen CFU of the endotoxin-treated mice slowed down during the second week, and their self-replicating ability was low. Fluctuations in the DNA synthesizing fraction of the spleen CFU suggested a variability in the ratio of the length of the S phase and the cell generation time.
|
2e67ca78-b7c0-45d0-a4c0-c0272b054231
| 0 |
[New interpretation of the symmetry of Cereus pedunculatus (Actiniaria) during embryonic development]. A spatial reconstitution is used to determine with precision the relative position of pharynx and mesenteries during the embryonic development of Cereus pedunculatus. Three successive stages are described for embryonic symmetrisation.
|
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