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

Forty six children suffering from Protein Energy Malnutrition (PEM) were classified according to the Wellcome classification. Their aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transferase were measured. Aspartate aminotransferase was raised in 20 patients (43.5%) and alanine aminotransferase was raised in 12 patients (26%). Y-glutamyl transferase was raised in only one patient suffering from marasmic kwashiorkor, who, in contrast to the rest of the patients had a marked rise in aminotransferases. The aminotransferase elevation correlated positively with a Severity Index calculated from height and weight retardation and serum albumin levels. It is suggested that the moderate rise in aminotransferases found in PEM is not due to damage to the liver. However, marked enzyme elevations can occur in a small minority of patients, suggestive of liver injury, probably caused by hepatotoxins.
 ...
PMID:Serum aminotransferases and gamma-glutamyl transferase in protein energy malnutrition. 286 77

Twenty horses of various ages had inadvertently ingested alfalfa hay contaminated with Senecio vulgaris. Among them, 4 died of liver disease. Blood was collected from affected horses at monthly intervals for 7 months and at the 9th and 14th months. The following serum enzymes and chemical items were assayed: aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, gamma-glutamyl transferase, sorbitol dehydrogenase, total bilirubin, BUN, glucose, cholesterol, inorganic phosphate, calcium, total protein, and albumin. Amino acid profiles, conjugated bile acids, sulfobromophthalein clearance times, and liver histopathologic changes via serial biopsies were also monitored. Liver histopathologic changes revealed lesions progressively increasing in severity. Aspartate aminotransferase and plasma amino acid ratios indicated chronic liver degeneration (0.05 level of significance). gamma-Glutamyl transferase and lactate dehydrogenase as well as BUN values fluctuated, but returned to within reference values. Horses appeared clinically normal 14 months after intoxication, but were unable to tolerate stress of exercise.
 ...
PMID:Clinicopathologic study of horses surviving pyrrolizidine alkaloid (Senecio vulgaris) toxicosis. 287 83

Glutamate and aspartate are putative excitatory neurotransmitters in the central nervous system. The present study utilized novel monoclonal antibodies against fixative-modified glutamate and aspartate and polyclonal antisera against the amino acid synthesizing enzymes, glutaminase and aspartate aminotransferase, to analyze the distribution of these amino acids in the rodent midbrain periaqueductal gray. Glutamate-, aspartate-, glutaminase- and aspartate aminotransferase-like immunoreactive neurons, fibers and processes are present throughout the rostrocaudal length of the periaqueductal gray. Glutamate- and glutaminase-like immunoreactive neurons displayed a similar homogeneous pattern of distribution, being localized predominantly to the lateral and dorsal subdivisions of the periaqueductal gray. Co-localization experiments suggest that glutamate and glutaminase are in fact co-contained within the same PAG neurons. Aspartate aminotransferase-like immunoreactive neurons were distributed in a pattern similar to glutamate and glutaminase with the exception that fewer cells were stained in the dorsocaudal and the rostral third of the PAG. Aspartate-like immunoreactive neurons were less numerous than glutamate-like immunoreactive cells and were located in the lateral aspect of the PAG. These results demonstrate a specific and distinct distribution of glutamate and aspartate immunoreactive neurons and support recent data suggesting that glutamate and aspartate serve as excitatory neurotransmitters in the PAG.
 ...
PMID:Localization of glutamate, glutaminase, aspartate and aspartate aminotransferase in the rat midbrain periaqueductal gray. 288 81

Beating rat heart cultures were prepared in vitro and infected with Coxsackie B-2 virus. The cells were evaluated in the post-infected period for changes in cardiac enzymes, alterations in beating frequency and cytotoxicity as measured by chromium 51 (51Cr) release. The cardiac enzymes, lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were measured in infected and uninfected controls over a period of 120 h. Enzyme levels in the infected cells remained essentially the same for the first 42 h as compared to the controls. At this time, the LDH levels increased rapidly reaching 116 +/- 24.8 U/l while the controls remained at 46.9 +/- 9.7 U/l. Aspartate aminotransferase levels increased at a slower rate and obtained a level of 104 +/- 20.2 U/l compared to 66.6 +/- 13.2 U/l in the control. Visual evidence of cellular damage as measured by decreased beating frequencies and the appearance of cytopathic effect was first noted at 42 h post-infection. Complete loss of cardiac beats and maximal viral cytopathic effect occurred at 96 h post-infection. Cardiac cellular damage as measured by cytotoxicity assay was found to parallel those changes seen in cardiac enzymes. No significant changes in cytotoxicity were observed for the first 24 h; however, at 48 h increased release of 51Cr was noted and visual evidence of viral replication also was present. The cardiac enzyme changes noted in beating rat heart cells appear to be similar to those changes reported in patients with viral-induced myocardial disease.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Coxsackie B-2 virus infection in rat beating heart cell culture. 300 12

The intra-cochlear distributions of aspartate aminotransferase and glutaminase, prominent enzymes of aspartate and glutamate metabolism, have been studied by quantitative microchemical techniques. Also measured was choline acetyltransferase, the enzyme synthesizing acetylcholine, and a marker for the olivocochlear bundle. Aspartate aminotransferase activity was highest in the stria vascularis, about half this high in the organ of Corti synaptic (hair cell) zones, somewhat lower in the organ of Corti non-synaptic (Hensen's cell) zones, lower yet in Reissner's and lowest in the tectorial membrane. Glutaminase, on the other hand, had its highest activity in synaptic zones, about a third of that activity in the organ of Corti non-synaptic zones, and a barely detectable activity in Reissner's and tectorial membranes, and stria vascularis. Seven days after transection of the olivocochlear bundle, no significant difference was found between lesion- and control-side aspartate aminotransferase or glutaminase activities, even though no choline acetyltransferase activity remained in the lesion-side of the organ of Corti. Both the distribution of aspartate aminotransferase activity and the lesion results would seem to implicate it in energy more so than neurotransmitter metabolism. The distribution of glutaminase activity could be consistent with a role in neurotransmission; however, the lesion data were unable to demonstrate a specific association with the olivocochlear bundle.
 ...
PMID:Quantitative distributions of aspartate aminotransferase and glutaminase activities in the rat cochlea. 302

Data on 15 laboratory analytes obtained in 145 prospectively investigated cholestatic patients with viral hepatitis, chronic intrahepatic cholestasis and extrahepatic biliary obstruction were submitted to a computer-based graphical evaluation using probabilistic test analysis. This revealed a marginal utility for alkaline phosphatase, gamma-glutamyltransferase and the direct/total bilirubin ratio at specific cut-off points for the exclusion of extrahepatic cholestasis (PVneg 90%-100%). Aspartate aminotransferase and alanine aminotransferase values with cut-off points at 200 U/l and 300 U/l, respectively, were powerful discriminators between acute viral hepatitis and the other disease categories, while lactate dehydrogenase, erythrocyte sedimentation rate and the ratios gamma-glutamyltransferase/alanine aminotransferase as well as total bilirubin/gamma-glutamyltransferase were useful at specific cut-off points indicating the absence of this diagnosis (PVneg 92%-100%). An aspartate aminotransferase/alanine aminotransferase ratio above 1.5 and serum gamma-globulin concentrations above 20 g/l strongly suggested cholestasis due to chronic parenchymal liver disease (PVpos 92% and 90%, respectively). This graphical approach to laboratory data analysis enhances the understanding of the interrelations between cut-off points and sensitivity, specificity and predictive values and also of the influence of disease prevalence on disease prediction. It also adds to present knowledge by demonstrating the clinical relevance of several readily available, albeit rarely utilized diagnostic analytes.
 ...
PMID:Graphical analysis of laboratory data in the differential diagnosis of cholestasis: a computer-assisted prospective study. 306 41

Aspartate aminotransferase from the archaebacterium Sulfolobus solfataricus, a thermoacidophilic organism isolated from an acidic hot spring (optimal growth conditions: 87 degrees C, pH 3.5) was purified to homogeneity. The enzyme is a dimer (Mr subunit = 53,000) showing microheterogeneity when submitted to chromatofocusing and/or isoelectric focusing analysis (two main bands having pI = 6.8 and 6.3 were observed). The N-terminal sequence (22 residues) does not show any homology with any stretch of known sequence of aspartate aminotransferases from animal and bacterial sources. The apoenzyme can be reconstituted with pyridoxamine 5'-phosphate and/or pyridoxal 5'-phosphate, each subunit binding 1 mol of coenzyme. The absorption maxima of the pyridoxamine and pyridoxal form are centered at 325 and 335 nm, respectively; the shape of the pyridoxal form band does not change with pH. The enzyme has an optimum temperature higher than 95 degrees C, and at 100 degrees C shows a half-inactivation time of 2 h. The above properties seem to be unique even for enzymes from extreme thermophiles (Daniel, R. M. (1986) in Protein Structure, Folding, and Design (Oxender, D. L., ed) pp. 291-296, Alan R. Liss, Inc., New York) and lead to the conclusion that aspartate aminotransferase from S. solfataricus is one of the most thermophilic and thermostable enzymes so far known.
 ...
PMID:Purification and characterization of aspartate aminotransferase from the thermoacidophilic archaebacterium Sulfolobus solfataricus. 313 25

The diagnostic value of the enzymatic fluorometric method for total serum bile acids (TSBA) and for radioimmunoassay measurement for conjugated cholic acid (CCA) or chenodeoxycholic acid was compared with that of routine liver function tests in 223 patients with liver disease, 88 healthy subjects, and 118 patients affected by other diseases. The value of the tests for screening in the general population was assessed by simulation, using estimates of disease prevalence. TSBA was significantly more sensitive (78%) but less specific (94%) than CCA (sensitivity of 69%, specificity of 98%). Aspartate aminotransferase was nearly as sensitive (74%) as TSBA, but significantly less specific (93%) than CCA. CCA provided the highest positive predictivity (98%), even in a screening simulation (32%). With the use of sequential aspartate aminotransferase measurement followed by CCA, this value rose to 100%. This test procedure appears to be the best screening method for liver diseases available at present.
 ...
PMID:Diagnostic value of serum immunoreactive conjugated cholic or chenodeoxycholic acids in detecting hepatobiliary diseases. Comparison with levels of 3 alpha-hydroxy bile acids determined enzymatically and with routine liver tests. 360 29

L-Hydrazinosuccinate, which has been shown to be a slow-, tight-binding inhibitor of aspartate aminotransferase (EC 2.6.1.1) in vitro, was tested as an inhibitor in vivo of the enzyme as well as other pyridoxal enzymes. Intraperitoneal administration to mice at a dose of 0.6 mmol/kg rapidly decreased aspartate aminotransferase activities in liver and kidney cytosols to a minimal level lower than 10% of the original, and no appreciable reversal of the inhibition was observed after 24 h; at lower doses the activities were significantly recovered during the same period following an initial marked decrease. Of the other pyridoxal enzymes tested, alanine aminotransferase in liver was the most sensitive to the inhibitor. It was initially inhibited as severely as aspartate aminotransferase, but the inhibition was reversed considerably faster. Aspartate aminotransferase activities in brain and heart were less severely affected than those in liver and kidney; they were less markedly lowered initially and were substantially recovered after 24 h. Consistent with the observed organ specificity, heated extracts from brain and heart in the mice administered with the inhibitor showed relatively weak inhibitory activities in vitro to aspartate aminotransferase purified from pig heart, while the extracts from liver and kidney were strongly inhibitory.
 ...
PMID:In vivo inhibition of aspartate aminotransferase in mice by L-hydrazinosuccinate. 381 11

There is considerable evidence that pathways of the hippocampus use an excitatory amino acid as transmitter. We have attempted to immunocytochemically identify excitatory amino acid neurons in the hippocampus of the rat and guinea pig using antiserum to glutaminase and antiserum to aspartate aminotransferase, which have been proposed as markers for aspartergic/glutamergic neurons. Glutaminase-like immunoreactivity was seen in granule cells in the dentate gyrus and fibers and puncta associated with the mossy fiber pathway in the hilus and stratum lucidum of the hippocampus. At the ultrastructural level, glutaminase-like immunoreactivity was observed in mossy fiber terminals in the stratum lucidum. Glutaminase-like immunoreactivity was also seen in pyramidal cells in regio inferior and regio superior and in cells in layer two of the entorhinal cortex. Schaffer collateral terminals, commissural fiber terminals and perforant pathway terminals were not seen at the light microscopic level. Glutaminase-like immunoreactivity is thus found in the cell bodies of proposed excitatory amino acid neurons of hippocampal pathways, but does not appear to label all terminals. Aspartate aminotransferase-like immunoreactivity was not seen in any cells, fibers or terminals in the rat or guinea pig hippocampus.
 ...
PMID:Immunocytochemical localization of glutaminase-like and aspartate aminotransferase-like immunoreactivities in the rat and guinea pig hippocampus. 388 76


<< Previous 1 2 3 4 5 6 7 8 9 Next >>