Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17174 (aspartate aminotransferase)
 14,872 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of the red blood cell enzymes transketolase, glutathione reductase, and aspartate transaminase, and their activation by the coenzymes thiamine, riboflavin, and pyridoxine, the pyruvate tolerance test, the leucocyte vitamin C concentration, and the activity in serum of gamma-glutamyl transferase were measured in a series of 35 patients with alcohol-related illness. The incidence of thiamine deficiency was 31% as assessed by the activation of transketolase, and 55% as assessed by the pyruvate tolerance test. The incidence of riboflavin deficiency was 23% and of ascorbic acid deficiency 91%. No cases of pyridoxine deficiency were detected. The pyruvate tolerance test was found to be a more sensitive test of thiamine deficiency than the transketolase activation, and the activation of red blood cell aspartate transaminase was found to be a poor indicator of pyridoxine deficiency. There was a poor correlation of the gamma-glutamyl transferase activity with the degree of vitamin deficiency, suggesting that alcohol exposure is only partly responsible for the observed vitamin deficiency.
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PMID:Detection and incidence of B and C vitamin deficiency in alcohol-related illness. 3 28

1. Thiamin, riboflavin and pyridoxine status of 'low-income-group' mothers and their newborn infants was assessed by analysing paired samples of maternal and umbilical cord blood for erythrocyte transketolase (EC 2.2.1.1) (ETK), erythrocyte glutathione reductase (EC 1.6.4.2) (EGR), and erythrocyte aspartate aminotransferase (EC 2.6.1.1) (EAA) activities. 2. The vitamin status of the infants was better than that of the mothers. 3. Most of the mothers and some of the infants had biochemical evidence of thiamin and riboflavin deficiency. 4. The pregnant women had a higher EAA activity and also higher stimulation with pyridoxal-5-phosphate than the non-pregnant women of the same community. 5. There was a significant correlation between maternal and umbilical blood samples for ETK and EGR activities, but not for EAA activity or any of the coenzyme stimulation tests.
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PMID:Enzymic evaluation of thiamin, riboflavin and pyridoxine status of parturient women and their newborn infants. 125

We describe optimized, ultraviolet spectrophotometric procedures for determination of erythrocyte transketolase, glutathione reductase, and aspartate aminotransferase activity, and their activation by their respective coenzymes--thiamine pyrophosphate, flavin-adenine dinucleotide, and pyridoxal-5-phosphate--as tests for vitamin B1, B2, and B6 deficiency. With these procedures we have investigated healthy subjects on normal and vitamin-supplemented diets, and a series of (mainly) alcoholic hospital in-patients. The enzyme procedures described have good precision and can be readily carried out in the routine laboratory. Abnormal transketolase activation correlated well with clinical evidence of vitamin B1 deficiency.
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PMID:Evaluation of methods of coenzyme activation of erythrocyte enzymes for detection of deficiency of vitamins B1, B2, and B6. 125 8

The unexpected autopsy finding of Wernicke encephalopathy in three children who died after prolonged enteral feeding prompted us to examine the incidence of thiamine deficiency in three high-risk pediatric populations. We also measured riboflavin and pyridoxine activity in the same groups. We used activated enzyme assays (erythrocyte transketolase, glutathione reductase, aspartate aminotransferase) to assess tissue stores of the dependent vitamin cofactors (thiamine (vitamin B1), riboflavin (vitamin B2), and pyridoxine (vitamin B6), respectively). Using our own reference ranges based on data from 80 healthy adults and children, we prospectively investigated the B vitamin status of three groups of children: (1) 27 patients who were fed solely by nasogastric tube for more than 6 months, (2) 80 children admitted to a pediatric intensive care unit for more than 2 weeks, and (3) 6 children receiving intensive chemotherapy. The upper limits for stimulated enzyme activity in control subjects were unaffected by age or gender (16% for transketolase, 63% for glutathione reductase, 123% for aspartate aminotransferase). Using these limits, 10 (12.5%) of 80 patients receiving intensive care and 4 of 6 patients receiving chemotherapy were thiamine deficient. Elevated levels returned to normal after thiamine supplementation. No patients were pyridoxine deficient, but 3 (3.8%) of the 80 patients receiving intensive care and 1 of the 6 patients receiving chemotherapy were also riboflavin deficient. We conclude that unrecognized thiamine deficiency is common in our pediatric intensive care and oncology groups. This potentially fatal but treatable disease can occur in malnourished patients of any age and is probably underdiagnosed among chronically ill children. Our findings may be applicable to other high-risk pediatric groups.
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PMID:Thiamine, riboflavin, and pyridoxine deficiencies in a population of critically ill children. 140 85

Isoenzyme analysis was conducted on the tachyzoite stage of 35 Toxoplasma gondii isolates. Fifteen enzyme systems were studied after isoelectrofocusing of tachyzoite extracts in polyacrylamide or agarose gels. Six enzyme systems showed variable electrophoretic patterns: aspartate aminotransferase (EC 2.6.1.1), glutathione reductase (EC 1.6.4.2), glucose phosphate isomerase (EC 5.3.1.9), amylase (EC 3.2.1.1), acid phosphatase (EC 3.1.3.2), and propionyl esterase. Their combination allows the description of 5 zymodemes among the 35 T. gondii isolates. Zymodeme 1 involves 6 isolates that are highly pathogenic to mice and for which oocysts could not be obtained. Isolates belonging to zymodemes 2, 3, and 4 are less pathogenic to mice and produced oocysts. Zymodeme 5 involves only 1 isolate, which was highly pathogenic to mice.
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PMID:Isoenzyme analysis of 35 Toxoplasma gondii isolates and the biological and epidemiological implications. 140 18

A total of 407 Leishmania and other Leishmania-like isolates obtained from patients, other vertebrates, sand fly vectors, and other arthropods from Kenya and other countries were characterized and compared with several World Health Organization and other well-characterized reference strains of Leishmania, Trypanosoma, Crithidia, Herpetomonas, and Leptomonas by cellulose acetate electrophoresis (CAE), using 20 enzyme systems. Analysis of the isoenzyme banding patterns (IBP) of the isolates generated isoenzyme profiles that were resolved as zymodemes and tabulated. Isolates that produced similar isoenzyme profiles in all 20 enzyme systems were placed into a particular Leishmania isoenzyme taxon, with the zymodeme designated numerically as Zn. A total of 66 zymodemes were recorded for the 407 isolates studied. To obviate the need to draw all 66 representative IBP for each of the 20 enzyme systems, the 66 zymodemes (Z1-Z66) were again placed into similarity groups represented by pattern number or Pn. This resulted in 23-50 IBP (Pn) per enzyme system. The highest number of IBP scored was for malate dehydrogenase (MDH) (P1-50) and the lowest score was for glucose-6-phosphate isomerase (GPI) (P1-23). From these different isoenzyme profiles or zymodemes, IBP of 14 (MDH, GPI, nucleoside hydrolase, phosphoglucomutase, malic enzyme, isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, mannose-6-phosphate isomerase, 6-phosphogluconate dehydrogenase, glutamate oxaloacetate transferase/aspartate aminotransferase, glutathione reductase, superoxide dismutase, fumarase, and glyceraldehyde-3-phosphate dehydrogenase) of the 20 enzyme systems were selected for computer-calculated numerical taxonomy. Consistent individual isoenzyme bands with similar relative mobilities of the 14 enzyme systems were scored into groups (allelomorphs, allozymes, or electromorphs) and used in cluster analysis. For each pattern in every profile, the presence of a consistent band was entered as 1 and its absence as 0. A total of 419 allozyme characters (variables) were scored for the 14 enzyme systems. Lastly, all different zymodemes sharing a particular IBP (Pn) within an enzyme system were counted and the total number was shown as a zymodeme frequency (Zf). Final analysis of the CAE isoenzyme profiles and cluster-dendrograms resulted in the identification of several potentially new species and subspecies of Leishmania and other Leishmania-like isolates from patients, sand flies, and animal reservoir hosts collected from Kenya and other locations in Africa. Zymodeme analysis of the Kenyan visceral and cutaneous leishmaniasis isolates resulted in the identification of 11 subpopulations of the L. donovani species complex and six subpopulations of the L. tropica species complex endemic to different geographic areas of Kenya.
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PMID:Biochemical characterization and zymodeme classification of Leishmania isolates from patients, vectors, and reservoir hosts in Kenya. 147 44

The isoenzyme profiles for ten enzymes of tachyzoites either grown in vivo in TG 180 mouse sarcoma cells or cultivated in vitro in human fibroblast cell culture were compared in eight cloned strains by means of isoelectric focusing in polyacrylamide gels. Fibroblast-cultivated tachyzoites of all strains tested showed an extra band in the LDH isoenzyme pattern that was not seen in tachyzoites from TG 180 mouse sarcoma cells. The isoenzyme patterns of four enzymes [aspartate aminotransferase (ASAT), glutathione reductase (GSR), glucose phosphate isomerase (GPI) and amylase] used to differentiate the strains did not change under the two different culture conditions. Nevertheless, the shift observed in the LDH isoenzyme pattern underlines the fact that isoenzyme analysis of Toxoplasma strains could be carried out with tachyzoites produced under the same culture conditions.
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PMID:Comparison of isoenzyme profiles of Toxoplasma gondii tachyzoites produced under different culture conditions. 169 15

Toxoplasma gondii strains are usually defined by biological parameters such as pathogenicity in mice. A characterization of toxoplasma strains by biochemical techniques has not been reported. In this study, extracts of tachyzoites of 7 toxoplasma strains were compared on the basis of their isoenzyme patterns for 39 enzymes by means of isoelectrofocusing in polyacrylamide gels. Eighteen enzymes gave clear and reproducible bands. Of these, 14 had identical electrophoretic patterns for all strains. Two different isoenzyme types were found for the enzymes aspartate aminotransferase, glutathione reductase, glucose phosphate isomerase, and amylase. This allowed the description of 3 isoenzyme pattern groups among the 7 toxoplasma strains. The possible relationship between biological behavior and isoenzyme pattern groups is discussed.
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PMID:Isoenzymic characterization of seven strains of Toxoplasma gondii by isoelectrofocusing in polyacrylamide gels. 246 94

We describe a fully automated method for the assessment of vitamin B1, B2 and B6 status using a centrifugal analyser. The activation of the red cell enzymes transketolase, glutathione reductase and aspartate aminotransferase) by their respective coenzymes were measured in freshly prepared haemolysate. The enzyme catalytic activities in the sample were measured with (maximal activity) and without (basal activity) the coenzyme, and the percentage activation was calculated. The between run precision for red cell transketolase, glutathione reductase and aspartate aminotransferase were 8.5%, 10.3% and 9.5% respectively. When whole blood was stored at room temperature for 6 hours, red cell aspartate aminotransferase activity significantly decreased (n = 10, p less than 0.05). There were no significant changes in the activities of the other two enzymes. For a group of 30 healthy young subjects, the mean (standard deviation) values for the percentage activation of transketolase, glutathione reductase and aspartate aminotransferase were 11.9% (7.3), 35.1% (19.1) and 85.3% (18.0), respectively. The vitamin status of a group of 86 pregnant women was assessed by this method; 2.3%, 8.1% and 8.1%, respectively, of the pregnant women showed a higher percentage activation for transketolase, glutathione reductase and aspartate aminotransferase than that found in the young subjects. Both groups correlated well with respect to the basal activity and the percentage activation of each enzyme. Basal activity was inversely proportional to the percentage activation. It is therefore suggested that the basal activity can be used as a second criterion in the assessment of vitamin status.
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PMID:Assessment of vitamin B1, B2 and B6 status by coenzyme activation of red cell enzymes using a centrifugal analyser. 340 87

The relationship between riboflavin and pyridoxine status was studied in 40 patients with sickle cell disease (SCD) and 12 normal children by measuring activation coefficients of erythrocyte glutathione reductase (EGRAC) and aspartate transaminase (ASTAC). Prevalence of riboflavin deficiency was significantly lower in SCD (42.5%) than in control subjects (83%) and there was less pyridoxine deficiency in SCD (10.3%) than control subjects (54.5%). Aspartate transaminase (AST) activities in SCD patients were double those in control subjects. Pyridoxine status of patients, but not of control subjects, was directly affected by riboflavin status as judged from significant correlations between EGRAC and both AST activity and ASTAC. Poor riboflavin status in patients may be restricting availability of pyridoxal phosphate (PLP) due to combined effects of enhanced PLP requirements and effects of poor riboflavin status on the synthesis of PLP by pyridoxine phosphate oxidase (PPO). PPO activity was no different in the two groups.
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PMID:Dependence of pyridoxine metabolism on riboflavin status in sickle cell patients. 360 73


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