Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.109 (AST)
 6,066 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This paper describes in vitro studies on the effects of environmental pollutants (SO2/NOx) in biological systems. Basic physical, chemical and biochemical parameters were analyzed to establish the rate of SO2/NOx absorption by the culture medium. It was shown that the pH remains constant for 24 h of exposure to gas concentrations up to 50 p.p.m. The concentration of ions resulting from absorption of each pollutant in the liquid phase is dependent on their concentration in the gas phase and on exposure time. Short exposure times and high gas dosages resulted in similar doses in the medium as long exposure periods and low gas dosages. The activities of a human serum standard (alkaline phosphatase, ALP; aspartate amino transferase, AST; alanine amino transferase, ALT; gamma-glutamyltransferase, gamma-GT; lactate dehydrogenase, LDH) were determined after gaseous exposure to SO2 and NOx. The results revealed a distinct decrease in the activity of LDH after 1, 3 and 5 h exposure to 200 p.p.m. SO2. The effects of the pollutants were assayed in vitro using fetal hamster lung cells (FHLC), rat hepatocytes and the cell line CO60. For the determination of toxic effects, it was shown that the plating efficiency was a more sensitive parameter than the assay for trypan blue exclusion. Toxicity indicated as an increase of LDH leakage was not observed from FHLC in culture. Instead, a decrease of LDH was found following SO2 exposition. This decrease was similar to that observed for the human serum standard. The induction of DNA single-strand breaks was determined as a measure of genotoxic effects. SO2 application decreased the rate of DNA single-strand breaks induced by N-nitroso-acetoxymethyl-methylamine in both FHLC and in rat hepatocytes. SO2 or NOx treatment of CO60 cells for 1 h did not result in the induction of DNA amplification. HSO3- added directly to the medium as the sodium salt, however, distinctly induced the amplification of SV40 DNA. The amplification rates induced by benzo[a]pyrene or dimethylbenzanthracene were neither influenced by SO2, NOx nor HSO3-. An additive effect of HSO3- with either benzo[a]pyrene or dimethylbenzanthracene for this biological parameter was therefore not observed.
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PMID:Effects of SO2 or NOx on toxic and genotoxic properties of chemical carcinogens. I. In vitro studies. 283 97

In experiments on 6 sheep the authors found the following enzyme activities in bacteria in the rumen fluid, bacteria adhering to the epithelium of the rumen wall and bacteria adhering to food particles in the rumen (given in nkat X g-1 bacterial dry weight): GDH (NADH): 725 +/- 165, 558 +/- 127, 661 +/- 153; GDH (NADPH): 558 +/- 338, 255 +/- 88, 565 +/- 139; GOAT (NADH): 46 +/- 23, 67 +/- 31, 66 +/- 14; GOGAT/NADPH: 58 +/- 27, 56 +/- 15, 65 +/- 29; GS: 153 +/- 65, 69 +/- 35, 71 +/- 32; ALT: 71 +/- 25, 43 +/- 20, 52 +/- 11; AST: 52 +/- 12, 33 +/- 16, 28 +/- 15. The results show that, except for GDH (NADPH), there were no significant differences between the given enzyme activities in the rumen fluid and in bacteria adhering to the rumen wall and to food. Adherent rumen bacteria have the same potential possibilities as the rumen fluid bacteria for the utilization of ammonia, particularly for the synthesis of glutamic acid, glutamine, alanine and aspartic acid, with the above enzymes as catalysts. By means of the GS/GOGAT system, adherent rumen bacteria can probably synthesize glutamic acid in the presence of a limited NH3 concentration in the rumen.
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PMID:Ammonia-utilizing enzymes of adherent bacteria in the sheep's rumen. 286 70

An in vivo model of liver hyperplastic noduligenesis was induced in rats by long-term administration of thioacetamide (TAM) (50 mg/kg/day i.p.). Three doses of 50 mg/kg of an antitumoral Rh(III) complex were administered at 14, 9 and 5 days before the end of TAM treatment. Plasma and urine were obtained from either TAM or Rh(III) complex or TAM plus Rh(III) complex treated rats to determine the interactions of both substances with the biochemical parameters related to liver function. The rise in alkaline phosphatase (ALP), leucine aminopeptidase (LAP), gamma-glutamyl transferase (GGT) and the unchanged activities in the aspartate and alanine aminotransferases (AST, ALT) in plasma of TAM-treated rats indicated that the disease induced by this substance can be considered as a chronic obstructive biliary disease with indices of cell proliferation and tumors. The increased concentration of bilirubin both in the plasma and urine of TAM-treated rats suggested liver cholestasis and hepatobiliary obstruction. The very low values of creatinine clearance indicated that there was some degree of kidney failure due to the effect of TAM. The increased concentration of ammonia both in plasma and urine were probably a consequence of the decreased flux in the urea cycle in the liver. The Rh(III) complex alone did not produce significant changes in the plasma enzyme activities. The only significant changes were found in the concentrations of uric acid and ammonia in the urine. When the Rh(III) complex was administered to TAM-treated rats, significant restoration of the following parameters were observed: plasma enzymatic activities, blood bilirubin and ammonia, uric acid and creatinine in the urine and the creatinine clearance. These results suggest that the altered liver function induced by TAM can be restored by Rh(III) complex. The mechanisms by which this complex acts to counteract the TAM-induced changes are not yet established.
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PMID:Effect of a rhodium complex on alterations of hepatic function in thioacetamide-induced hyperplastic noduligenesis in rats. 288 38

Male Wistar rats aged 75 and 150 days were given high fat diet (36.5 weight % and 30 weight % fat) over a period of 14 days. The growth (PER, NPR) and utilization (NPU, LPU) parameters of protein biological value and liver phosphoenolpyruvate carboxykinase (PEPCK) activity were determined. In another experiment, the time dependence of liver gluconeogenesis enzyme (PEPCK and fructose-1,6-diphosphatase /FDP-ase/) and transaminase (alanine and aspartate aminotransferase /ALT, AST/) activities during 24 days' administration of the diet were determined. A 14 days' high fat intake had a negative effect on protein utilization in the organism of 75- and 150-day-old animals, which was more pronounced in the younger age group (a bigger drop in net protein utilization /NPU/ and greater stimulation of PEPCK activity). In 150-day-old animals the negative effect of a high fat intake was already manifested on the 6th to 10th day of the diet to the same degree as in the younger animals on the 14th day, as seen from the increase in all the enzyme activities. The paper presents findings on differences in the degree of the negative effect of a high fat intake on protein utilization with reference to age.
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PMID:Influence of the time of intake of a high fat diet on gluconeogenesis. 293 54

The ratio of the serum aspartate to alanine amino-transferase levels (AST/ALT) is often used as a clue to the etiology of the underlying liver disease. This ratio is usually greater than 2.0 in alcoholic liver disease and less than 1.0 in patients with chronic hepatitis and chronic cholestatic syndromes. We analyzed the AST/ALT ratio in 177 patients with various forms of nonalcoholic chronic liver disease who underwent medical evaluation and percutaneous liver biopsy. In the majority of cases of chronic viral hepatitis, the AST/ALT ratio was less than 1.0. However, there was a statistically significant correlation between the AST/ALT ratio and the presence of cirrhosis. Among 100 patients with chronic type B hepatitis, the mean AST/ALT ratio was 0.59 in those without cirrhosis and 1.02 in those with cirrhosis. Furthermore, the AST/ALT ratio often rose to greater than 1.0 when cirrhosis first became manifest. Thus, the finding of an AST/ALT ratio of greater than 1.0 in a patient with nonalcoholic liver disease should suggest the presence of cirrhosis. In addition, the use of the AST/ALT ratio as a means of separating alcoholic and nonalcoholic liver disease must be tempered with the knowledge that this ratio may be less helpful in the presence of cirrhosis.
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PMID:Ratio of serum aspartate to alanine aminotransferase in chronic hepatitis. Relationship to cirrhosis. 313 26

Increased alanine and aspartate aminotransferase (ALT and AST) serum levels are usually considered expressions of cellular necrosis, especially in hepatocytes. They represent cellular damage due to burn which, according to many authors, becomes normal before discharge of patients. We studied 43 consecutive burned patients, both during and after recovery, from a minimum of 120 to a maximum of 640 days, and an average of 18.62 blood samples were taken from each patient. Hepatitis A and B markers were tested. Results showed a 67.44% increase in aminotransferases in patients during recovery and a 25.58% increase after discharge. No neopositivity was observed for hepatitis A and B markers. We therefore conclude that the increase of enzymes during recovery expresses a toxic-infective phase and this increase, contrary to what was believed, does not always drop to normal values at time of discharge. Instead, after discharge, higher values can be a manifestation of a Non-A Non-B hepatitis.
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PMID:Alanine and aspartate aminotransferase serum levels in burned patients: a long-term study. 361 54

The authors evaluated the Cobas FARA centrifugal analyzer with respect to pipetting precision and accuracy, instrument temperature, spectrophotometric response, and analytic performance for the assay of five serum enzymes and glucose. Spectrophotometric response, temperature response, pipetting precision, and accuracy were satisfactory. However, sufficient time must be allowed for cuvet contents to reach a stable temperature before measurements are made. Total day-to-day imprecision (within plus between run) was less than 5% (coefficient of variation) for aspartate and alanine aminotransferases (AST; Enzyme Commission classification number [EC] EC 2.6.1.1; and ALT; EC 2.6.1.2); alkaline phosphatase (AP; EC 3.1.3.1); gamma-glutamyltransferase (GGT; EC 2.3.1.2); lactate dehydrogenase (LD; EC 1.1.1.17); creatine kinase (CK; EC 2.7.3.1); and glucose assays. Results compare well with those obtained with other current clinical chemistry analyzers; correlation coefficients were greater than 0.993. Sample-to-sample carryover was negligible, and method linearity was satisfactory for all tests.
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PMID:A clinical evaluation of the Cobas Fara clinical chemistry analyzer for some routine serum enzymes and glucose. 367 42

1. PK and LDH activities in the muscle of Periophthalmodon schlosseri and Boleophthalmus boddaerti were at least 100-fold higher than their respective activities in the liver. 2. The ratio of PK:PEPCK in liver of B. boddaerti was smaller than that of P. schlosseri. 3. PK:PEPCK ratios in both fishes were intermediate between those of aerobic and anaerobic organisms. 4. MDH activity was higher than other enzymes assayed in the liver of both fishes. 5. The ratios of LDH:MDH in the liver of both mudskippers were comparable to those of anaerobic organisms. 6. AST was at least eight times more active than ALT in the liver of both fishes. 7. In the muscle of these mudskippers, the aspartate content was significantly less than that of alanine. 8. Exposure of these fishes to various experimental conditions led to changes in specific activities of PEPCK, LDH, AST and ALT.
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PMID:Activities of enzymes associated with phosphoenolpyruvate metabolism in the mudskippers, Boleophthalmus boddaerti and Periophthalmodon schlosseri. 367 93

Viral hepatitis in chimpanzees produces negligible symptomatology, and serum aminotransferase changes may be minimal. To maximize the predictive value of these determinations, which are the only serum indicators available for non-A non-B (NANB) hepatitis infection, normal ranges for aspartate and alanine aminotransferases (AST, ALT) were examined and categorized according to age and sex. Males were found to have higher values than females, and adults higher values than juveniles. The kinetic method used and the values obtained are described. Differences in methodologies and reporting units are discussed.
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PMID:The clinical chemistry of chimpanzees. I. Determination of aminotransferase baseline values for hepatitis studies. 615 21

Activities of alpha-hydroxybutyrate- and lactate dehydrogenases (HBDH, LDH), aspartate- and alanine aminotransferases (AST, ALT), alkaline phosphatase, alpha-amylase as well as content of total proteins, glucose, cholesterol, triglycerides and Ca2+ were estimated sprectrophotometrically in blood serum of rat males within 2 hrs after thermic burns of the III degree involving 15% the body surface. The burns caused about 2-fold increase in activities of LDH, HBDH and AST and in content of triglycerides in blood serum but did not affect the other biochemical patterns. Adrenalectomy, carried out within 3 days before the burns, accelerated and pseudoadrenalectomy decreased the early postburn enzymatic activation. Preadministration of reserpine, phentolamine and obsidane (propranolol) decreased distinctly the hyperenzymic reaction observed after the burn stress.
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PMID:[Effect of adrenalectomy and anti-adrenergic preparations on the development of hyperenzymic and biochemical changes in the blood in burns]. 620 53


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