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)

Human myocardium with focal myocytolysis (vacuolar degeneration, colliquative myocytolysis) was examined by routine light microscopy and by immunoperoxidase staining techniques for creatine kinase (CK) M and B, myoglobin, lactate dehydrogenase (H4)(LDH-1), and aspartate aminotransferase (AST, GOT). Sections of myocardium were selected from autopsy and surgical specimens from patients with and without clinical morphologic evidence of ischemic heart disease. Areas of coagulation necrosis showed loss of enzyme staining, while both normal and myocytolytic cells stained darkly. These results indicate that fibers with myocytolysis retain enzymes and other proteins, indicating sarcolemmal integrity, which is not present in fibers with coagulation necrosis. The implication of these findings is that fibers with myocytolysis are viable; thus, myocytolysis may be a reversible form of myocardial alteration that does not necessarily lead to cell death and eventual myocardial fibrosis.
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PMID:Myocytolysis (vacuolar degeneration) of myocardium: immunohistochemical evidence of viability. 620 21

In myopathic disorders, abnormal serum enzyme activities are seen primarily in diseases of skeletal muscle where the condition involves the muscle fibers themselves. In denervation myopathies, serum enzyme activities are usually normal. The most dramatic increases of serum enzymes, particularly creatine kinase, are found in the dystrophic diseases, particularly Duchenne dystrophy. A review is given here of the many causes of abnormal serum enzyme activities where the source of enzymes is believed to be skeletal muscle. These include the dystrophies, various types of trauma, exercise, drug- and poison-induced causes including alcohol, malignant hyperthermia, inflammatory diseases, and miscellaneous causes. Tissue and serum activities are summarized for the commonly performed serum enzymes, i.e., CK, LD, AST, and aldolase. An extensive tabular and current description of the various types of dystrophies is given along with serum CK and pyruvate kinase activities.
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PMID:The enzymology of skeletal muscle disorders. 637 45

Total serum creatine kinase and isoenzyme levels were studied in five patients with polymyositis. In all five patients, CK-MB isoenzyme was demonstrated by the column chromatography and electrophoretic method, although there was no evidence of myocardial infarction. The persistent elevation of CK-MB in patients with polymyositis is in contrast to the usual transient increase in myocardial infarction. Serial CK-MB isoenzyme quantitation can be used to distinguish myocardial infarction from polymyositis. CK-MB is a more sensitive indicator than AST and LDH as a monitoring device, but offers no advantage over total CK activity.
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PMID:CK-MB isoenzyme in patients with polymyositis. 708 Dec 91

It is still undecided in clinical medicine if an increased serum CK-MB level indicates irreversible myocardial damage. We measured CK and AST activities on three serum samples obtained during the first 24 hours following admission of patients with a clinical history suggesting myocardial ischemia. Isoenzymes were not separated when CK and AST activities were less than 300 U/L and 35 U/L respectively, but were fractionated when the enzyme activities doubled during the first 24 hours even within their normal ranges. Over a three-year period this doubling occurred in 30 patients, one of whom was admitted twice to the hospital. The serum CK-MB fractions of these patients were 6% or greater in 26 and less than 6% in 5 admissions. The final clinical diagnosis given to the patients on 20 of these 26 admissions was acute subendocardial infarction. None of the five patients with a CK-MB fraction less than 6% had a clinical diagnosis of acute myocardial infarction. A comparative study of 102 patients with higher average enzyme activities but without doubling of both enzymes during a 24-hour period, did not yield a CK-MB of 6% or greater. None of this group of patients was diagnosed clinically as having had acute myocardial infarction.
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PMID:Detection of ischemic myocardial injury in patients with normal, or moderately elevated, serum CK and AST activities. 711 21

Aspartate aminotransferase (EC 2.6.1.1:AST) is known to have two isoenzymes, one associated with the cytoplasm (c-AST) and the other with the mitochondria (m-AST). We studied the relationships of m-AST activity in the coronary sinus blood to left ventricular function, coronary blood flow, water content and high-energy phosphate stores of the left ventricle following hypothermic ischemic cardiac arrest. Under cardiopulmonary bypass with hypothermia of 20 degrees C of myocardial temperature, 120 min of aortic occlusion was employed in 15 mongrel dogs. Left ventricular function (peak left ventricular pressure, left ventricular end-diastolic pressure, max dp/dt, cardiac index, left ventricular stroke work index), coronary blood flow, myocardial oxygen consumption, myocardial enzyme activity (m-AST, CK-MB), myocardial water content and high-energy phosphate stores (adenosine triphosphate, creatine phosphate) of the subendocardium of the left ventricle were measured. Data was obtained in the control state, and after 0, 30 and 60 min of reperfusion. Significant negative correlations were obtained between m-AST activity and peak left ventricular pressure (r = -0.81, p less than 0.001), max dp/dt (r = -0.83, p less than 0.001), cardiac product (r = -0.73, p less than 0.01), coronary blood flow (r = -0.59, p less than 0.05), adenosine triphosphate level (r = 0.72, p less than 0.01) and creatine phosphate level (r = -0.72, p less than 0.02) after 60 min of reperfusion. Significant positive correlations were obtained between m-AST activity and left ventricular end-diastolic pressure (r=0.75, p less than 0.01) and water content (r = 0.78, p less than 0.01) after 60 min of reperfusion. These results led to the assumption that serum m-AST activity in the coronary venous blood is a useful index to evaluate the degree of myocardial injury.
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PMID:Studies on the significance of serum mitochondrial aspartate aminotransferase activity following ischemic cardiac arrest. 714 3

When organ damage is assessed from activities of tissue enzymes in plasma, it is assumed that variations in tissue enzyme content, both among individuals and between different sites within an organ, are small. We checked these assumptions, using canine heart and liver. We determined creatine kinase (CK; EC 2.7.3.2), lactate dehydrogenase (LD; EC 1.1.1.27), aspartate aminotransferase (AST; EC 2.6.1.1), and glucosephosphate isomerase (GPI; EC 5.3.1.9) in different sites of different hearts; the results showed CVs of 9.3, 9.1, 13.5, and 8.2%, respectively. A small transmural gradient in CK is found in the left ventricle. Determination of AST, GPI, and alanine aminotransferase (ALT; EC 2.6.1.2) in different sites of different livers gave CVs of 12.5, 17.0, and 11.6%, respectively. Most of the total variation is interindividual. The unreliability of early data and conflicting reports on transmural myocardial enzyme gradients are discussed. We conclude that by use of proper enzymes, such as LD for the heart and ALT for the liver, organ damage can be estimated, although there are inherent problems in relating enzyme release to loss of tissue mass.
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PMID:Distribution of enzymes in dog heart and liver; significance for assessment of tissue damage from data on plasma enzyme activities. 729 36

A multi-enzyme reference material was prepared from seven enzymes of asparatate aminotransferase (AST, EC 2.6.1.1), alanine aminotransferase (ALT, EC 2.6.1.2), alkaline phosphatase (ALP, EC 3.1.3.1), lactate dehydrogenase (LD, EC 1.1.1.27), creatine kinase (CK, EC 2.7.2.2), gamma-glutamyltranspeptidase (gamma-GT, EC 2.3.2.2) and amylase (AMY, EC 3.2.1.1) which were purified from human sources including established human cell lines. The enzymatic properties of the material closely resembled those of human serum. In lyophilized form the preparation was stable for at least 200 days when stored at 40 degrees C. Intermethod comparisons of the enzyme activities in 80 clinical specimens were done by correcting the mean values with calibration constants for different assay methods resulting from use of a human serum, the multi-enzyme reference and a commercial control serum. The results from the comparison for the six enzymes of AST, ALT, LD, CK, gamma-GT and AMY in use of the multi-enzyme reference were almost the same as those with use of a human serum as a calibrator, but were not satisfactory for ALP. Even though further search for more reliable material for ALP is required the multi-enzyme reference material can be used for standardization in clinical chemistry.
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PMID:Multi-enzyme reference material from established human cell lines and human sources. 753 22

We have developed a new multienzyme control serum, Seraclear-HE, which was designed to function not only as an accuracy and precision control serum but also as an intermethod calibrator for unifying interlaboratory clinical enzyme data in terms of reference method values. Seraclear-HE contains as analytes the following enzymes of human origin only: aspartate aminotransferase (AST, EC 2.6.1.1) and lactate dehydrogenase (LD, EC 1.1.1.27) from erythrocytes; alanine aminotransferase (ALT, EC 2.6.1.2) from a hepatoma cell line; alkaline phosphatase (ALP, EC 3.1.3.1) from an amnion cell line; creatine kinase (CK, EC 2.7.3.2) from an embryo kidney cell line; gamma-glutamyltransferase (GGT, EC 2.3.2.2) from a macrophage cell line; and amylase (AMY, EC 3.2.1.1) from urine and saliva. The seven partly purified enzymes were lyophilized in partially delipidated human serum containing sucrose (50 g/L), pyridoxal 5'-phosphate (30 mmol/L), and other stabilizers. The material is stable for at least 2 years at temperatures < or = 10 degrees C. For two concentrations of this preparation, reference method values (mainly International Federation of Clinical Chemistry and Japan Society of Clinical Chemistry) obtained at both 30 degrees C and 37 degrees C are assigned.
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PMID:Multienzyme control serum (Seraclear-HE) containing human enzymes from established cell lines and other sources. 1: Preparation and properties. 753 43

The effects of strenuous physical exercise on the serial changes in the haematological, biochemical and hormonal markers were investigated. A group of 14 soldiers, aged 24-36 years, took part in a military training course for about 13 weeks. After severe exercise stress, an increase (90%) in the number of peripheral blood leucocytes was observed. The degree of leucocytosis showed a close correlation with the values of some serum parameters, such as concentrations of aspartate aminotransferase (AST; r = 0.747), lactate dehydrogenase (LD; r = 0.748), blood urea nitrogen (r = 0.756), creatine kinase (CK; r = 0.637), manganese-superoxide dismutase (Mn-SOD; r = 0.508), alanine aminotransferase (ALT; r = 0.542) and uric acid (r = 0.538), and concentrations of urinary parameters, such as vanilmandelic acid (r = 0.429) and free cortisol (r = 0.437). The subjects showing prominent leucocytosis over 9500 cells.microliters-1 exhibited a lower concentration of serum cholinesterase than those who showed milder leucocytosis. The serum Mn-SOD concentration was closely correlated with the serial changes in serum concentrations of AST, ALT, LD and CK, indicating exercise-induced muscle and liver damage. The change in peripheral leucocyte number was assumed to be diagnostically informative and may be a prognostic marker, reflecting organ damage and restoration after strenuous physical exercise.
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PMID:Leucocytosis as a marker of organ damage induced by chronic strenuous physical exercise. 878 93

Plasma CK concentrations have been widely used as the primary muscle enzyme marker for diagnosis and progression of myositis. Recently, total CK and CK-MB serum concentrations have been compared to, and used in conjunction with, serum concentrations of aspartate aminotransferase in diagnosis of myositis. The algorithmic use of CK, AST, and aldolase plasma concentrations to diagnose and categorize patients with myopathy may be a useful method of diagnosing specific muscle disease without invasive procedures. CAIII, as a specific marker for skeletal muscle damage, may replace CK as the enzyme of choice in diagnosis and progression of myositis and other muscle disease. Additional studies are required to determine the usefulness of carbonic anhydrase for the diagnosis and assessment of myositis.
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PMID:Evaluation of laboratory tests as a guide to diagnosis and therapy of myositis. 785 25


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