Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.1 (aspartate aminotransferase)
21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seven healthy men volunteers received 6.6 +/- 1.3 (SD) percent-hours of halothane oxygen anesthesia without surgery. Serum bilirubin, alanine aminotransferase, and aspartate aminotransferase significantly increased after anesthesia, which may indicate subclinical liver-cell damage. Creatine kinase of skeletal muscle origin increased above 90 U/liter in six subjects, indicating subclinical muscle-cell damage. Cortisol, triiodothyronine uptake, thyroxine, and free thyroxine index increased significantly immediately after anesthesia. Serum bromide concentrations had increased by fivefold on the second day after anesthesia, and on the ninth day was still elevated fourfold. Oral temperatures increased 0.7 degrees C 6 h post-anesthesia, possibly because of increased thyroxine activity. Lactate dehydrogenase, hydroxybutyrate dehydrogenase and gamma-glutamyltransferase activities did not change significantly. No drugs administered during the course of this study chemically interfered with any of the test methods used.
...
PMID:Effect of halothane anesthesia on muscle, liver, thyroid, and adrenal-function tests in man. 0 91

Acute 15, 30 and 60-minute hypoxia induced in a rabbit placed in the altitude chamber at the atmospheric pressure of 260 mm Hg was an experimental model for a hypoxic state. An increase in the amount of aspartate in the brain under conditions of 15-minute hypoxia and its decrease with prolongation of the hypoxia period up to 1 h may be explained by different mechanisms of amino acids metabolic transformations under these conditions. Changes in the content of aspartate are adequate to these in the activity of aspartate aminotransferase. An increase in the glutamate content in the brain the 30- and 60-minute hypoxic effect is accompanied by a rise of the activity in the glutamine synthesis enzyme (glutamine synthetase). Dynamics of the aspartate quantitative changes in the brain in different periods of acute oxygen deficiency affecting metabolic shifts in amino acids metabolism may serve as an index of the hypoxic effect gravity.
...
PMID:[Peculiarities of amino acids transformation in brain under conditions of acute hypoxic hypoxia]. 3 21

The content of free amino acids, activity of aspartate and alanine transaminase, number of sulphydryl groups in fish tissues were studied as affected by lethal amounts (3.2 g/l) of blue-green algae. Blue-green algae have a certain affect on fishes not only by excreting biologically active substances in the process of vital activity and decay but also changing the gas regime of the medium (the oxygen content lowers, the amount of carbon dioxide increases). Under the algae effect the total content of free amino acids in the fish liver, intestine and muscles increases, mainly due to a rise in the content of glutamic acid with threonine and aspartic acid with serine. These changes are most essential in the liver, intestine and are less pronounced in the muscles. Under the effect of blue-green algae the activity of aspartate transaminase increases in the heart, brain and decreases in the intestine. The activity of alanine transaminase enhances in the heart, intestine and brain. The ration value for these enzymes changes significantly in the brain, liver, intestine, but does not differ from the control in the muscles.
...
PMID:[Amino acid composition and transaminase activity in fish tissues, in a medium containing Cyanophyceae]. 10 39

Haemodynamic adaptation was studied during the first 10 h after aorto-coronary bypass surgery. In a control group of 12 patients the heart was fibrillating and perfused during cardiopulmonary bypass (at 30 degrees C), and in 11 patients cold cardioplegic arrest was used. The first 4--5 h were characterized by rewarming, with increasing oesophageal temperature, cutaneous vasoconstriction and elevated systemic vascular resistance (SVR). A phase of vasodilation followed. In the control group the oxygen uptake index increased by 57% during rewarming, but the cardiac index (CI) was constant (about 2.9 l . min-1.m-2). The arterio-venous oxygen content difference (AVDo2) therefore increased (max. 3.0 mmol . l-1). The postoperative left ventricular performance was better and the serum levels of aspartate aminotransferase (ASAT) during the first 2 days postoperatively were lower in the cardioplegic patients than in the controls, indicating more efficient myocardial preservation. In the cardioplegic-hypothermic group, CI was constant at about 3.2 l . min-1.m-2 (significantly higher than in the control group) and AVDo2 remained normal during the rewarming period. The heart rate was lower initially in the cardioplegic patients than in the controls, implying a favourable influence on myocardial oxygen consumption. The better myocardial function in the cardioplegic-hypothermic group was associated with an only moderately increased SVR. This suggests that the elevated SVR in the control group could have been due to myocardial depression.
...
PMID:Myocardial performance early after aorto-coronary bypass surgery. Cardioplegic arrest versus coronary perfusion. 31 58

Enzymic memory is a kinetic phenomenon observable in double displacement mechanisms. The defining feature of enzymic memory is the occurrence of different rates of transfer for a common transferable group from the substituted enzymes obtained with different donor substrates. Memory behavior was previously demonstrated for both the bovine and human liver rhodaneses (EC 2.8.1.1). Steady state kinetic tests for enzymic memory have now been done with ascorbate oxidase (EC 1.10.3.3) and aspartate aminotransferase (EC 2.6.1.1). The results were positive with ascorbate oxidase, which showed an oxygen reactivity ratio of 1:20:300 for the reduced enzymes obtained with reductate, araboascorbate, and ascorbate, respectively. Results were negative for the aminotransferase tested with the alternate donors glutamate and cysteine sulfinate, with oxaloacetate as the common acceptor. The structural basis of the ascorbate oxidase results was probed by comparison of both the ultraviolet absorption and fluorescence spectra of the oxidized enzyme with those of the reduced forms obtained with ascorbate and reductate. The results are consistent with a conformational basis for the memory phenomenon.
...
PMID:Enzymic memory. Steady state kinetic and physical studies with ascorbate oxidase and aspartate aminotransferase. 47 84

Six patients with spontaneously occurring arrhythmias were studied to assess the antiarrhythmic properties of helium. The patients were divided into two subgroups breathing air, helium-oxygen (heliox), and nitrogen-oxygen (nitrox) in an alternating sequence during successive 20-min periods under continuous ECG surveillance at rest. There were no significant reductions in spontaneously occurring premature ventricular beats while breathing heliox, compared to breathing air of nitrox. Alternating the breathing gases in this manner caused no change in plasma concentration of electrolytes or in activity of serum glutamic-oxaloacetic transaminase or lactic acid dehydrogenase. We conclude that helium does not affect spontaneously occurring chronic premature ventricular beats in conscious resting man when it is breathed for a period of up to 20 min.
...
PMID:Absence of antiarrhythmic effects of helium in patients with spontaneous premature ventricular beats at rest. 53 59

Two-hundred consecutive patients thought to have suffered a myocardial infarction were admitted to a randomised, double-blind controlled trial of oxygen or air administered by MC mask throughout the first 24 hours in hospital. Forty-three patients in whom myocardial infarction was not subsequently confirmed were excluded from the analysis. The remaining air and oxygen groups were comparable except for a significantly higher PaO2 and serum aspartate aminotransferase level in the oxygen group. There was no significant difference in mortality, incidence of arrhythmias, use of analgesics, or systolic time intervals between the two groups, although a higher incidence of sinus tachycardia was found in those given oxygen. There appears to be no evidence of benefit from the routine administration of oxygen in uncomplicated myocardial infarction.
...
PMID:Controlled trial of oxygen in uncomplicated myocardial infarction. 77 7

1. The apparent Michaelis constants of the glutamate dehydrogenase (EC 1.4.1.3), the glutamate-oxaloacetate transaminase (EC 2.6.1.1) and the glutaminase (EC 3.5.1.2) of rat brain mitochondria derived from non-synaptic (M) and synaptic (SM2) sources were studied. 2. The kinetics of oxygen uptake of both populations of mitochondria in the presence of a fixed concentration of malate and various concentrations of glutamate or glutamine were investigated. 3. In both mitochondrial populations, glutamate-supported respiration in the presence of 2.5 mM-malate appears to be biphasic, one system (B) having an apparent Km for glutamate of 0.25 +/- 0.04 mM (n=7) and the other (A) of 1.64 +/- 0.5 mM (n=7) [when corrected for low-Km process, Km=2.4 +/- 0.75 mM (n=7)]. Aspartate production in these experiments followed kinetics of a single process with an apparent Km for glutamate of 1.8-2 mM, approximating to the high-Km process. 4. Oxygen-uptake measurement with both mitochondrial populations in the presence of malate and various glutamate concentrations in which amino-oxyacetate was present showed kinetics approximating only to the low-Km process (apparent Km for glutamate approximately 0.2 mM). Similar experiments in the presence of glutamate alone showed kinetics approximating only to the high-Km process (apparent Km for glutamate approximately 1-1.3 mM). 5. Oxygen uptake supported by glutamine (0-3 mM) and malate (2.5 mM) by the free (M) mitochondrial population, however, showed single-phase kinetics with an apparent Km for glutamine of 0.28 mM. 6. Aspartate and 2-oxoglutarate accumulation was measured in 'free' nonsynaptic (M) brain mitochondria oxidizing various concentrations of glutamate at a fixed malate concentration. Over a 30-fold increase in glutamate concentration, the flux through the glutamate-oxaloacetate transaminase increased 7--8-fold, whereas the flux through 2-oxoglutarate dehydrogenase increased about 2.5-fold. 7. The biphasic kinetics of glutamate-supported respiration by brain mitochondria in the presence of malate are interpreted as reflecting this change in the relative fluxes through transamination and 2-oxoglutarate metabolism.
...
PMID:Comparative studies on glutamate metabolism in synpatic and non-synaptic rat brain mitochondria. 88 64

Three hundred patients with acute pancreatitis have been studied. Pancreatitis was associated with alcoholism in 207, biliary tract disease in 51 and other conditions in 42. Twenty-two patients died, and an additional 34 patients required more than one week of treatment in the intensive care unit. Retrospective analysis of the first 100 patients identified 11 objective findings which correlated with the occurrence of serious illness or death. They were, on admission, age over 55 years, blood glucose level over 200 milligrams per cent, white blood count over 16,000 per cubic millimeter, serum lactic dehydrogenase level over 350 International units per liter and serum glutamic-oxalacetic transaminase level over 250 Sigma Frankel units per cent. During the initial 48 hours of therapy, the findings were hematocrit value decrease over 10 percentage points, serum calcium level below 8 milligrams per cent, base deficit over 4 milli-equivalents per liter, a blood urea nitrogen level increase over 5 milligrams per cent, estimated fluid sequestration over 6 liters and arterial oxygen tension less than 60 millimeters of mercury. Prospective application of these signs in the latter 200 patients permitted the accurate early identification of those with severe pancreatitis. Only one of 162 patients with fewer than three of these early features was seriously ill or died, while 24 of 38 patients with three or more early positive findings were seriously ill or died. The objective early identification of patients with severe pancreatitis permits more vigorous management of this group and also provides a basis for the selection of patients for the evaluation of proposed improved therapies. Percutaneous peritoneal dialysis in severe pancreatitis was evaluated in ten patients, with three or more positive early signs, who were randomly assigned to dialysis or continued conventional care. Morbidity was strikingly reduced in patients who underwent dialysis, and while death or more than nine days of intensive care occurred in two of five patients who did not receive dialysis, all five patients having dialysis recovered after fewer than nine days of intensive care treatment. Serious illness or death occurred in 31 of the first 100 patients but in only 26 of the more recent 200 patients. There has been a similar fall in mortality from 15.0 to 3.5 per cent. Factors which may contribute to this improvment include the objective early identification of patients with severe disease, the avoidance of early laparotomy whenever practical, the prolongation of nasogastric suction until all evidence of pancreatic inflammation has resolved, careful monitoring of respiratory function and early treatment of pulmonary complications and peritoneal dialysis in patients with severe disease.
...
PMID:Prognostic signs and nonoperative peritoneal lavage in acute pancreatitis. 94 Oct 75

Oral administration of graded doses of paracetamol to dogs produced hepatic necrosis with some similarities to the clinical syndrome seen in man following a paracetamol overdose. Coma, with raised levels of arterial ammonia, was produced and the aspartate aminotransferase levels became markedly elevated in 2 animals who survived more than 24 h. However, the extent of the hepatic necrosis and the time of survival following paracetamol administration were too variable for this model to be of value for the testing of new methods of temporary liver support. When paracetamol was given by intraperitoneal injection many of the animals died of respiratory distress. Significant methaemoglobinaemia was detected, which was associated with a reduction in the arterial partial pressure of oxygen and was partly reversed by the administration of methylene blue.
...
PMID:A dog model of fulminant hepatic failure produced by paracetamol administration. 121 24


1 2 3 4 5 6 7 8 9 10 Next >>

---