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

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

Polymerized hemoglobin solutions (Hb-based oxygen carriers; HBOCs) and a second-generation perfluorocarbon (PFC) emulsion (Perflubron) are in clinical trials as temporary oxygen carriers ("blood substitutes"). Plasma and serum samples from patients receiving HBOCs look markedly red, whereas those from patients receiving PFC appear to be lipemic. Because hemolysis and lipemia are well-known interferents in many assays, we examined the effects of these substances on clinical chemistry, immunoassay, therapeutic drug, and coagulation tests. HBOC concentrations up to 50 g/L caused essentially no interference for Na, K, Cl, urea, total CO2, P, uric acid, Mg, creatinine, and glucose values determined by the Hitachi 747 or Vitros 750 analyzers (or both) or for immunoassays of lidocaine, N-acetylprocainamide, procainamide, digoxin, phenytoin, quinidine, or theophylline performed on the Abbott AxSym or TDx. Gentamycin and vancomycin assays on the AxSym exhibited a significant positive and negative interference, respectively. Immunoassays for TSH on the Abbott IMx and for troponin I on the Dade Stratus were unaffected by HBOC at this concentration. Tests for total protein, albumin, LDH, AST, ALT, GGT, amylase, lipase, and cholesterol were significantly affected to various extents at different HBOC concentrations on the Hitachi 747 and Vitros 750. The CK-MB assay on the Stratus exhibited a negative interference at 5 g/L HBOC. HBOC interference in coagulation tests was method-dependent-fibrometer-based methods on the BBL Fibro System were free from interference, but optical-based methods on the MLA 1000C exhibited interferences at 20 g/L HBOC. A 1:20 dilution of the PFC-based oxygen carrier (600 g/L) caused no interference on any of these chemistry or immunoassay tests except for amylase and ammonia on the Vitros 750 and plasma iron on the Hitachi 747.
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PMID:Effect of hemoglobin- and Perflubron-based oxygen carriers on common clinical laboratory tests. 929 68

Acceptable biochemical markers of ischaemic heart disease are now considered to include myoglobin, CK-MB isoforms, CK-MB, and cardiac troponins T and I. AST (SGOT), total LD and LD isoenzymes, and total CK activity measurements are regarded as obsolete for this purpose. All acceptable biochemical markers must be available, if required, with a turnaround time of < 20 min. Such a service can either be provided by quantitative assays in a well-equipped laboratory or by qualitative point-of-care (bedside) devices (except for the CK-MB isoform assay) which can also be used in patients' homes and ambulances. There is, however, a pressing need for the careful side-by-side assessment of the relative merits of each of these biochemical markers to permit definitive conclusions about their future usage. A particular problem is the lack of primary standards for CK-MB and troponin I assays. The sensitivity of the initial ECG is about 50% for detecting myocardial damage; thus the use of biochemical markers may contribute to the early diagnosis and monitoring of thrombolytic therapy and these possible applications are examined. In addition, biochemical markers are presently the gold standard for the diagnosis of minor myocardial damage. There is now good evidence that biochemical markers, particularly the cardiac troponins, have a prognostic function in ischaemic heart disease although such findings pose unanswered clinical management questions. At the same time, it is recognized that there is often no need at all for the use of any biochemical marker when the clinical diagnosis is unequivocal, other than for prognosis, monitoring thrombolytic therapy, or diagnosing reinfarction.
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PMID:The use of biochemical markers in ischaemic heart disease: summary of the roundtable and extrapolations. 958 61

Perioperative myocardial infarction as well as other major cardiac events induced by myocardial ischemia during and after a more complex or long-lasting operation represents a permanent threat for a successful outcome. High number of cardiac ischemic events especially following major vascular surgery and in elder subjects requires early, sensitive and specific diagnostic markers. This review paper presents conventional as well as novel biochemical methods fulfilling the above mentioned criteria. Until now used estimations of traditional enzyme activities (aspartate aminotransferase and lactate dehydrogenase) are either entirely discarded or subsequently lose their importance (i.e. activities of total creatine kinase and its MB-isoenzyme) an instead modern methods that estimate the amounts of specific cardiac proteins--troponins T and I, constituents of myocardial contractile apparatus--released from ischemized heart are used. Patient's monitoring by means of these cardiac markers allows an early, rapid and reliable estimation of perioperative myocardial infarction enabling possible to arrange an immediate effective treatment. Recently the myocardial regulatory protein troponin I is considered the most specific cardiac marker the plasma level of which does not increase in acute damage and chronic diseases of skeletal muscles, nor in chronic renal failure. (Ref. 52.)
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PMID:[Biochemical markers of perioperative myocardial infarct in non-cardiac surgery]. 1057 43

A random sample of patients presenting to this hospital in 1996 and 2000 with chest pain was assessed retrospectively with respect to patient bed stay and associated costs. The laboratory testing protocol had been changed from traditional cardiac markers AST, CK and CKMB, to troponin I, in the intervening period. The average bed stay for patients with chest pain of non-AMI origin was reduced by 2 days, as a result of the change in testing protocol. As ward costs contribute 49% of total cost of treatment, this resulted in decreased cost per patient, and more efficient use of hospital beds.
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PMID:The effect of a change from conventional cardiac enzymes to troponin I on overall hospital costs in patients with suspected myocardial infarction. 1222 30

The myotoxic activity of the venom of Crotalus durissus terrificus is demonstrable by increased serum levels of the enzymes creatine kinase (CK), lactate dehydrogenase (LD), and aspartate aminotransferase. Serial measurements of CK, LD and their isoenzymes in bite victims showed a pattern similar to that observed in acute myocardial infarction, although the clinical course and electro- and echocardiographic data did not suggest cardiac involvement. These data have raised the hypothesis that crotalid venom preferentially causes damage to type I and/or type IIa fibers, which contain quantities of CK-MB and LD1 similar to those found in cardiac fibers. In order to detect a possible concomitant silent cardiac involvement, seven children with severe crotalid envenoming were studied. Serum troponin I, determined more than once in each patient, were found to be normal. These data demonstrate the absence of cardiac involvement in these patients envenomed by C. durissus terrificus and confirmed the skeletal muscle origin of the elevated CK-MB.
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PMID:Absence of myocardial involvement in children victims of Crotalus durissus terrificus envenoming. 1475 4

For many years, cardiac markers have been used to assist cardiologists in the diagnosis and management of patients with cardiovascular disease. At first, enzyme activities of aspartate aminotransferase, lactate dehydrogenase and creatine kinase have been used in diagnosing patients with chest pain in order to differentiate those with acute myocardial infarction. In the field of cardiac markers, emphasis is currently put on the use of protein markers such as myoglobin, and cardiac troponin T or I. Troponins are very highly cardiac specific and their concentration in blood increase only from four to six hours after the onset of chest pain. Today we obligatorily use two markers, the first being the early one (myoglobin, isoform of creatine kinase), which is very sensitive and shows up in the circulation one to two hours after myocardial damage. Confirmation of myocardial damage can be obtained by definite markers (troponin I or T), which are highly specific of myocardial damage.
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PMID:[Biochemical markers in acute coronary syndrome]. 1520 94

3-Hydroxy-3-methyl-glytaryl coenzyme A (HMG-CoA) reductase inhibitors ("statins") have been proved to be extremely useful in the management of hypercholesterolemia, as well as in prevention of primary and secondary coronary heart disease. However, they may produce rare but severe muscle-related symptoms such as myopathy and rhabdomyolysis. Recent findings in vitro have shown that statins can reduce cardiomyocyte viability. The exact mechanism of statin myotoxicity still remains unclear. Diltiazem as CYP3A4 inhibitor, is a well recognized risk factor of skeletal muscles myopathy, if co-administered with simvastatin. It is not known whether such interaction affects myocardial efficiency causing biochemical changes. The experiments were performed on thirty six New Zealand white rabbits. The animals were divided into four groups receiving: 0.2% MC (control group): diltiazem (5 mg/kg); simvastatin (50 mg/kg) or diltiazem + simvastatin, daily for 14 days (po). The following biochemical parameters were estimated: creatine kinase (CK), serum transaminases (ALT and AST), as well as myocardial injury markers: troponin I (Tnl) and creatine kinase MB (CK-MB). Simultaneous administration of simvastatin and diltiazem caused 23-fold increase (p < 0.01), in rabbit serum CK levels and 20-fold increase (p = 0.056) in TnI levels, as compared to the initial values. Also in these rabbits significant increase in CK (12411,60 vs 839.87 IU/L) and TnI (0,26 vs 0,014 ng/mL), as compared to control group were observed. Significant increase in CK (12411,60 vs 1100,92 IU/L) and TnI (0,26 vs 0,012 ng/mL), as compared to diltiazem alone were noted, too. This may suggest another mechanism of drug-drug interaction than the one based on CYP3A4 inhibition if the impact on cardiac or skeletal muscle is considered.
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PMID:The influence of simvastatin at high dose and diltiazem on myocardium in rabbits, the biochemical study. 1735 90

Ingestion of aqueous 70% ethanol extract of Ballota nigra (400 mg/kg body weight for 7 days) by albino rats (n=10) was investigated to study its effects on glucose, total cholesterol, triglycerides, aspartate aminotransferase (AST), alanine aminotransferase (ALT), troponin I (TnI), serum creatine kinase (CK), total protein, total bilirubin and blood urea. Ballota nigra extract caused a significant decrease in blood glucose, total serum cholesterol and CK levels. Blood levels of TnI, AST, ALT, triglycerides, total bilirubin, total protein and blood urea were unchanged. The hypoglycemic effect of Ballota nigra extract on albino rats was further investigated by conducting a glucose tolerance test intraperitoneally (IPGTT). Healthy rats that were fasting for 18 hours followed by administration of a dose of 400 mg/kg body weight of the crude extract of Ballota nigra, orally. A significant decrease in blood glucose levels (after 15, 30, and 45 minutes) with a significant increase in serum insulin level (after 15 and 30 minute) was noted. These results suggest that, the crude extract of Ballota nigra have hypoglycemic, insulin-releasing and cholesterol lowering effects in rats.
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PMID:Effects of Ballota nigra on blood biochemical parameters and insulin in albino rats. 1762 72

The aim of this study was to establish cardiac damage related to nocturnal ischemia using heart type fatty acid binding protein (h-fabp), which reaches detectable levels in plasma after being released from myocytes in case of ischemia in obstructive sleep apnea syndrome (OSAS) patients without coronary artery disease (CAD). Fifty patients diagnosed with OSAS in our sleep laboratory with polysomnographic analysis (PSG), who did not have any previous history of cardiac disease and in whom CAD was ruled out with myocardium perfusion scintigraphy, were included in the study. Control group comprised 19 volunteers without history of cardiac disease and risk factors in whom OSAS was excluded with PSG analysis. Blood samples were drawn from the patients to examine h-fabp, creatine kinase (CK), creatine kinase-MB (CK-MB), aspartate aminotransferase (AST), troponin I levels before and after sleep. No significant difference was found in CK, CK-MB, AST, Troponin I, and h-fabp levels before and after sleep in patient and control groups (p > 0.05). No significant difference was found between groups in terms of CK, CK-MB, AST, and Troponin I levels before and after sleep, while a significant difference was found between them with regard to h-fabp levels before (p = 0.006) and after sleep (p = 0.022). When arithmetical mean of the fabp levels before and after sleep was taken in the patient group, it was found that mean value of h-fabp was associated with the desaturated period in sleep which was under 80% (p = 0.04). H-fabp seems to be a marker that will enable the detection of cardiac injury in the early asymptomatic period in OSAS patients before development of disease that can be detected by imaging methods. Further studies are required to investigate the relation between the value of h-fabp and the development of cardiac dysfunction in the long term.
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PMID:Evaluation of the relationship between heart type fatty acid binding protein levels and the risk of cardiac damage in patients with obstructive sleep apnea syndrome. 1823 25

Direct, dose dependent effects of the nose-horned vipers (Vipera ammodytes ammodytes) venom on various parameters of cardiac action in isolated rat hearts were examined. Biochemical (protein content, SDS polyacrylamide gel electrophoresis) and biological (minimum haemorrhagic and necrotizing dose and lethal dose (LD(50))) characterization of the venom was performed before testing. The hearts were infused with venom doses of 30, 90 and 150 microg/mL for 10 min followed by 30 min of wash out period. Left ventricular pressure, coronary flow, heart rate, atrioventricular conduction, myocardial oxygen consumption, incidence and duration of arrhythmias were measured and relative cardiac efficiency was calculated. Cardiac CPK, LDH, AST and troponin I were measured as biochemical markers of myocardial damage. The venom caused dose dependent electrophysiological instability and depression of contractility and coronary flow. Effects on the heart rate were biphasic; transient increase followed by significant slowing of the frequency. Relative cardiac efficiency decreased as oxygen consumption remained high relative to the heart rate-contractility product, indicating purposeless expenditure of oxygen and energy. Effects by the dose of 30 microg/mL were highly reversible while the dose of 90 mug/mL caused damages that were mostly irreversible. The dose of 150 mug/mL induced irreversible asystolic cardiac arrest.
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PMID:Dose dependent effects of standardized nose-horned viper (Vipera ammodytes ammodytes) venom on parameters of cardiac function in isolated rat heart. 1831 64


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