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)

We describe an enhancement of our earlier computer program which allows calculation of decision thresholds, sensitivity and specificity, and likelihood ratios of negative and positive test results for any chosen value of sensitivity or specificity. The program will also plot continuous receiver operating characteristic and decision level curves which permit examination of the contours created by using all the available data. We illustrate the value of these routines by showing that the sensitivity and specificity of serum aspartate aminotransferase changes during the course of a myocardial infarction.
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PMID:A computer program to determine diagnostic decision thresholds and likelihood ratios illustrated with aspartate aminotransferase activities after a myocardial infarction. 261 33

To evaluate whether the right ventricle releases significant amount of cardiac enzymes during myocardial infarction, a clinicopathologic study of 50 patients with 60 infarcts was performed. Myocardial infarct size was determined at autopsy and compared with the corresponding peak serum lactate dehydrogenase and aspartate aminotransferase. Anterior and posterior infarcts had similar anatomic size, peak enzyme values, and coefficients of correlation (r = 0.86-0.88 versus r = 0.82-0.84 for lactate dehydrogenase). However, by disregarding the right ventricular infarct component considering the left ventricular infarction only, the coefficient of correlation between infarct size and peak serum lactate dehydrogenase decreased from r = 0.84 to r = 0.59 (P = 0.09), in 14 posterior infarcts while no change was observed in 24 anterior infarcts (r = 0.88). This indicates, that a considerable amount of enzymes released during posterior infarction originated from the right ventricle which was not the case for anterior infarction.
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PMID:Right ventricular infarction: larger enzyme release with posterior than with anterior involvement. 270 15

We examined the kinetics of the catalytic activities of aspartate aminotransferase (AST, EC 2.6.1.1) isoenzymes in serum of 28 patients with myocardial infarction who were to receive either intracoronary urokinase--reperfusion angiographically proved--or conventional therapy (control group). Cytosolic (soluble) AST (s-AST) activity in serum increased rapidly immediately after recanalization, reaching a maximum 12 h after the onset of infarction. In the control group, this peak was reached 28 h after the onset (P less than 0.001). Peak s-AST activity was similar in the two groups. Peak activity and peak time for mitochondrial AST (m-AST) were the same for the two groups of patients; intervention that affects myocardial perfusion caused only a slight additional increase in m-AST activity in the early post-infarct period. There may be advantages to measuring m-AST, which is briefly influenced by reperfusion, instead of the usual cytosolic enzymes for assessment of myocardial damage in patients with myocardial infarction treated with thrombolytic therapy.
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PMID:Effects of therapeutic coronary reperfusion on aspartate aminotransferase isoenzymes in sera of patients with acute myocardial infarction. 273 62

We evaluated the utility of serum enzyme and isoenzyme activities for detecting autopsy-proved perioperative myocardial infarction in patients who died after cardiac operations. We studied 79 patients who had autopsies performed after coronary artery bypass grafting or valve replacement, or both. Thirty-seven had histologic evidence of a perioperative myocardial infarction. We found statistically significant differences between the group of patients with infarction and the group without infarction when we compared the mean activities of creatine kinase, creatine kinase MB, aspartate aminotransferase, and the lactate dehydrogenase-1/lactate dehydrogenase-2 ratio. The postoperative changes in serum enzymes were analyzed by logistic regression for their relation to perioperative myocardial infarction. Creatine kinase MB exhibited the best diagnostic association with the presence of perioperative myocardial infarction. The lactate dehydrogenase-1/lactate dehydrogenase-2 ratio correlated to a lesser extent with infarction. Adjustment of the diagnostic cutoff to 133 U/L for creatine kinase-MB measured 15 hours after operation yielded a sensitivity of 0.60 and a specificity of 1.0. This study demonstrates that no combination of enzyme activity changes after operation can completely discriminate all patients with perioperative myocardial infarction from those without. Nonetheless, measurement of creatine kinase MB activity provide 96% accuracy for diagnosing infarction at a prevalence of 10%.
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PMID:The predictive value of serum enzymes for perioperative myocardial infarction after cardiac operations. An autopsy study. 281 7

Plasma levels of glutamate, alanine, free fatty acids (FFA), citrate, glucose, insulin, lactate, creatine kinase and aspartate aminotransferase were determined frequently during the first 2-48 h after onset of chest pain in 10 patients who developed acute myocardial infarction (AMI) and in 8 who did not (non-AMI). An initial decrease in plasma glutamate and increase in alanine was found in AMI compared to non-AMI patients. The AMI group showed early, moderate rises of plasma FFA and citrate concentrations, positively related to the initial ST-segment elevation and to the enzymatic estimated infarct size. The AMI patients were continuously hyperglycaemic, but their relative insulin response i.e. plasma glucose/insulin ratio was identical to that of non-AMI patients. Lactate values did not differ between the two groups. Via participation in the malate-aspartate shuttle and by shunting pyruvate to alanine instead of lactate, glutamate is of importance for maintaining myocardial glucose utilization. Our finding of initial low plasma glutamate concentrations after onset of myocardial infarction suggests insufficient glutamate supply to the ischaemic myocardium. On basis of this and animal experiments, an external supply of glutamate might be a 'metabolic' treatment of AMI, alternative or additional to glucose-insulin-potassium infusion in order to promote myocardial glucose oxidation.
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PMID:Altered plasma concentrations of glutamate, alanine and citrate in the early phase of acute myocardial infarction in man. 287 95

The vitamin B6 status of 84 patients with acute myocardial infarction was compared with that of 84 control subjects. Pyridoxal and pyridoxal 5'-phosphate (PLP) in plasma and erythrocytes, as well as the basal and total potential activity of the PLP-dependent enzyme aspartate aminotransferase in erythrocytes, were measured for a comprehensive assessment of vitamin B6 status. The mean levels of all vitamin B6 indexes (except pyridoxal) were lower in the patients than in the control subjects. The differences were statistically significant, except for erythrocyte PLP and total potential enzyme activity. The adjusted relative odds of a myocardial infarction for subjects in the lowest quartile of plasma PLP was about 5 times higher when compared with those in the highest quartile (relative odds = 5.2, 95% confidence interval = 1.4 to 18.9). Similar findings were found with the other vitamin B6 indexes. No significant association between infarct size, as estimated by creatine kinase level, and the vitamin B6 indexes was observed.
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PMID:Low vitamin B6 status in patients with acute myocardial infarction. 291 56

To determine the incidence and natural history of left ventricular thrombosis in acute transmural myocardial infarction we performed serial two-dimensional echocardiography in 51 patients. Seventeen patients had inferior infarcts. None of these developed left ventricular thrombosis. The remaining 34 patients had anterior infarcts. Ten of these developed left ventricular thrombus at an average of 4 +/- 2 days after admission. All patients with left ventricular thrombosis had apical akinesia or dyskinesia. Patients with anterior myocardial infarction and akinesia or dyskinesia of the apex are at high risk of developing left ventricular thrombosis. Peak aspartate aminotransferase and lactate dehydrogenase enzyme activity were of little value in identifying this high risk group.
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PMID:Left ventricular thrombosis in acute transmural myocardial infarction. 317 36

Although measurements of creatine kinase isoenzyme 2 (CK-MB) are often used to diagnose acute myocardial infarction, their sensitivity and specificity are less than 100%. Because skeletal muscle contains more CK and less aspartate aminotransferase (AST) than cardiac muscle, the CK/AST ratio might provide a useful adjunct in evaluating the source of a supranormal value for CK. I established the following decision levels in a retrospective study of 342 patients: ratios less than 14 (if total CK was 300-1200 U/L), less than 20 (CK 1201-2000 U/L), or less than 25 (CK greater than 2000 U/L) suggested myocardial infarction, with a sensitivity of 95% and a specificity of 65%. In a validation study with 277 additional patients, liver disease and alcohol abuse caused erroneous results, leading to exclusion of 22% of these patients. In the remaining cases, sensitivity was 94%, specificity 90%. The CK/AST ratios changed little with time, suggesting that a single value would be adequate for evaluating patients with increased CK.
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PMID:Creatine kinase:aspartate aminotransferase activity ratio as an indicator of the source of an increased creatine kinase activity. 319 92

Serum samples from patients admitted to a coronary care unit with a history of acute chest pain suggestive of myocardial infarction in the previous 12 h were obtained on admission and at 6 and 12 h, thereafter. Creatine kinase (CK), CK-MB isoenzyme, CK-MM sub-bands, myoglobin, and lactate dehydrogenase (LD) isoenzymes were examined. Changes were evaluated in relation to the diagnosis obtained from clinical examination, serial electrocardiography and 'routine' cardiac enzymes (CK, aspartate transaminase and alpha-hydroxy butyrate dehydrogenase daily for 3 days following admission). The slope of the logarithms of CK, CK-MB activity and CK-MB concentration in the early post infarct period fully distinguished between infarct and non-infarct patients. Measurement of myoglobin and lactate dehydrogenase isoenzymes was less sensitive. Serial estimation of CK-MM sub-band patterns allowed the time from infarction to be estimated. Serial estimation of CK in the 12 h following admission can be substituted for conventional daily enzyme estimations for the diagnosis of acute myocardial infarction in patients with onset of chest pain within the previous 12 h. This could reduce laboratory and in-patient costs.
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PMID:Early diagnosis of myocardial infarction by timed sequential enzyme measurements. 321 18

Eight patients with severe peripheral vascular atherosclerosis scheduled for abdominal aortic surgery were investigated to detect coexisting coronary artery disease. None of the patients had a history of angina pectoris or previous myocardial infarction. Preoperative computerised thallium-201 dipyridamole myocardial scintigraphy was abnormal in all patients, showing either myocardial scar tissue and/or ischaemia with redistribution and/or low washout. In all but one patient, the serum level of creatin kinase was elevated during the first postoperative days. In two patients, the serum concentrations of aspartate aminotransferase and lactate dehydrogenase were elevated. None of the patients showed clinical or electrocardiographical signs of acute myocardial infarction. Thallium-201 dipyridamole myocardial imaging is a new noninvasive method for detection of ischaemic heart disease in patients with severe peripheral atherosclerosis who are unable to perform a bicycle exercise test. The new programme for determination of regional washout appeared to be very precise and may be especially applicable in the case of low washout values.
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PMID:Thallium-201 myocardial scintigraphy during dipyridamole-induced coronary hyperaemia. First experiences with a new regional washout programme. 321 87


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