Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Currently available chromatographic assays of the progestative drug nomegestrol acetate in human plasma are not suitable for monitoring drug kinetics more than 24 h after clinical dosage. A specific and sensitive enzyme immunoassay was therefore developed. A 3(O-carboxymethyl)oxime derivative of nomegestrol acetate was synthesized and coupled to bovine serum albumin in order to raise polyclonal antibodies in rabbits. The enzymatic tracer was obtained by coupling the 3(O-carboxymethyl)oxime derivative to acetylcholinesterase (E.C.3.1.1.7.). HPLC fractionation of human plasma samples followed by enzyme immunoassay revealed the presence of cross-reacting metabolites. An automated procedure of metabolite separation was developed using silica bonded with diol groups (Diol Bakerbond column). This procedure ensured assay specificity. The quantification limit in human plasma was 0.1 ng/ml. Mean repeatability (intra-assay variation) and reproducibility (inter-assay variation) were 9 and 15%, respectively. The enzyme immunoassay allowed monitoring of the kinetics of nomegestrol acetate 144 h after oral administration of a single 5 mg dose. Values for human samples were in excellent agreement with those assayable by HPLC followed by u.v. detection.
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PMID:Enzyme immunoassay for nomegestrol acetate in human plasma. 821 81

The blood esterase that mediates the metabolism of flestolol, an ultra short-acting beta blocker, was characterized. Esterase activity occurred in plasma of human, dog, rat, and guinea pig and not in erythrocytes of the same species. The esterase activity was greatest in humans and guinea pigs followed by dogs and rats. Purified human serum cholinesterase was very active against flestolol while human serum albumin was slightly active. Human and bovine erythrocyte membrane acetylcholinesterases, electric eel acetylcholinesterase, human hemoglobin, dog, rat, chicken, and bovine serum albumin were all inactive. Esterase activity with flestolol was inhibited in human, dog, and rat blood by echothiophate, eserine, and sodium fluoride. Guinea pig blood esterase activity was inhibited by echothiophate and sodium fluoride, but not by eserine. Metabolic interaction studies indicated that succinylcholine, procaine, and chloroprocaine interfere with the metabolism of flestolol in human blood. Succinylcholine prolonged the in vitro half-life of flestolol in dog blood, but acetylcholine, procaine, and chloroprocaine had no effect. Flestolol did not affect the metabolism of procaine or chloroprocaine in human and dog blood. The metabolism rate of flestolol decreased in individuals with atypical, fluoride-resistant and silent forms of serum cholinesterase.
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PMID:Biochemical characterization of flestolol esterase. 823 65

Plasma myeloperoxidase levels in patients with cirrhosis were compared with those in patients with chronic hepatitis and healthy controls by means of a specific radioimmunoassay for myeloperoxidase. The mean concentration of plasma myeloperoxidase in cirrhotic patients (309.1 +/- 17.2 ng/ml, n = 41) was markedly higher than that in chronic hepatitis patients (222.6 +/- 17.2 ng/ml, n = 21) (p < 0.01) and normal controls (219.5 +/- 5.7 ng/ml, n = 50) (p < 0.01). Plasma myeloperoxidase showed good negative correlations with neutrocyte count (r = -0.32, p < 0.01), thrombocyte count (r = -0.40, p < 0.01), red blood cell count (r = -0.32, p < 0.01), serum albumin (r = -0.35, p < 0.01), and cholinesterase (r = -0.32, p < 0.02) and positive correlations with serum alkaline phosphatase (r = 0.49; p < 0.01) and lactate dehydrogenase (r = 0.31, p < 0.01) in patients with cirrhosis or chronic hepatitis. Among lactate dehydrogenase isozymes, a good positive correlation was seen between plasma myeloperoxidase and lactate dehydrogenase-2 (r = 0.40, p < 0.01) and lactate dehydrogenase-1 (r = 0.03, p < 0.02). Plasma myeloperoxidase was significantly higher in the cirrhotic and chronic hepatitis patients with splenomegaly (341.1 +/- 19.4 ng/ml, n = 31) than in those without splenomegaly (217.4 +/- 12.2 ng/ml, n = 29) (p < 0.01). We also examined the difference between plasma levels of myeloperoxidase in the portal and peripheral blood.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:High plasma concentration of myeloperoxidase in cirrhosis: a possible marker of hypersplenism. 824 62

Zabicipril (S 9650) is a new angiotensin-converting enzyme inhibitor whose hydrolysis in vivo produces the pharmacologically active metabolite zabiciprilat (S 10211). Two competitive enzyme immunoassays specific for either zabicipril or zabiciprilat have been developed using acetylcholinesterase (E.C. 3.1.1.7) as label. Antibodies were raised in rabbits after immunization with lysil derivatives of zabicipril or zabiciprilat coupled with bovine serum albumin. Assays were performed in 96-well microtiter plates coated with a monoclonal antibody raised against rabbit immunoglobulin G, thus ensuring rapid separation of free and bound fractions of the tracer. The analysis does not require any extraction step. In the case of the assay of zabiciprilat, interference generated by endogenous angiotensin-converting enzyme (ACE) was eliminated by the addition of perindoprilat, another ACE inhibitor. Perindoprilat was not recognized by the antibodies (cross-reactivity < 0.01%) and did not affect assay efficiency. The specificity of the assays was checked by high-performance liquid chromatography of human plasma samples obtained after oral administration of 2 mg of zabicipril. No metabolites or endogenous substances were detected. The mean reproducibility was 15% for the assay of zabicipril and 19% for the assay of zabiciprilat. The quantification limits were 1.2 ng/ml for the zabicipril assay and 0.8 ng/ml for the zabiciprilat assay. These assays are therefore suitable for pharmacokinetic studies and drug monitoring in clinical studies.
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PMID:Enzyme immunoassays for a new angiotensin-converting enzyme inhibitor, zabicipril, and its active metabolite in human plasma: application to pharmacokinetic studies. 824 53

The glutathione (GSH) S-transferases are believed to have dual functions as hepatic detoxifying enzymes and intrahepatic binding proteins. Little is known about their alterations in human liver diseases. Therefore, we have studied the relationship between the enzyme activity and rose bengal (RB) binding in hepatic cytosol and plasma indocyanine green (ICG) kinetics in patients with various liver diseases. The enzyme activity was measured in samples of hepatic cytosol obtained from 52 patients. In addition, the content of cationic and neutral transferases was estimated in 17 biopsy samples by densitometry of Coomassie blue stained sodium dodecyl sulphate polyacrylamide gel electrophoretograms. RB binding studies also were performed on cytosol samples. ICG kinetic parameters were determined using the two-compartment open model in 17 patients who were given the dye (0.5 mg kg-1) intravenously. Correlations between the enzyme activity and liver function tests, content of the enzyme, RB binding and ICG kinetic parameters were evaluated. The following results were obtained. (1) The enzyme activities were high in alcoholic liver disease, fatty liver and Gilbert's syndrome, and low in cirrhosis. (2) The enzyme activities were positively correlated with serum cholinesterase activity, serum albumin level and hepaplastin test, and negatively correlated with ICG retention rate at 15 min. (3) The enzyme activity, its content and RB binding affinity of the cytosol were positively correlated with each other. (4) The enzyme activity was positively correlated with hepatic ICG distribution volume. These results are consistent with the role of the GSH S-transferases as ligandins in intracellular storage of dyes.
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PMID:Relationship between content of hepatic glutathione S-transferases and the kinetics of indocyanine green elimination in various liver diseases. 825 11

The activities of lecithin-cholesterol acyltransferase (LCAT) and lipid transfer protein (LTP) were assayed using sensitive radioassay methods in controls (n = 113) and in patients with various liver diseases (n = 72). Plasma LCAT activity decreased with progression of hepatocellular damage. Plasma LTP activity in controls was 216 +/- 68 nmol/mL/h, and there were no significant differences between controls and patients with chronic hepatitis ([CH], 193 +/- 70), compensated liver cirrhosis (LC) with or without hepatocellular carcinoma ([HCC], 197 +/- 48 and 193 +/- 62, respectively), or decompensated liver cirrhosis ([dLC], 182 +/- 65). In acute viral hepatitis, LTP activity decreased significantly; however, the degree of reduction was not as dramatic as that for LCAT. There was no correlation between LCAT and LTP activity both in controls and patients with various liver diseases. LCAT activity was positively correlated with serum albumin (r = .52, P < 0.1) and cholinesterase (r = .37, P < .01) levels, and inversely correlated with serum bilirubin level (r = -.38, P < 0.1); there was no correlation between plasma LTP activity and these parameters of liver function. That plasma LTP activity did not change with hepatocellular damage may indicate that the liver in humans may not be the primary site of LTP production.
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PMID:Lecithin-cholesterol acyltransferase and lipid transfer protein activities in liver disease. 844 43

To investigate the efficacy of nerve growth factor (NGF) in promoting recovery from cholinergic damage, young (3-4 month old) and aged (22-23 month old) Fischer 344 rats received NMDA-induced unilateral lesions of the nucleus basalis of Meynert and subcutaneous osmotic pumps (2-week duration) connected to permanently implanted cannulas directed at the lateral ventricle ipsilateral to the lesion. Pumps were filled with either artificial CSF/rat serum albumin (the vehicle) or 5.0 micrograms of angiotensin-free, beta-NGF. Fourteen days after surgery, all subjects were sacrificed and their brains regionally dissected (frontal and occipital cortices, striatum, and dorsal and ventral hippocampi) and assayed for choline acetyltransferase (CAT) and acetylcholinesterase (AChE). Results indicated that the lesion decreased CAT and AChE levels within the frontal cortex of both young (29.8% and 39.4% depletion, respectively) and aged (30.5% and 34.8% depletion, respectively) animals. Only in young animals did NGF reduce these lesion-induced CAT (by 34.2%) and AChE deficits (by 65.5%). In fact, NGF exacerbated frontal cortical CAT depletions in aged animals in that percent depletion was 11.3% more following treatment (30.5% vs. 41.8% depletion in Aged/CSF and Aged/NGF groups, respectively). Lower CAT and AChE levels were found in the striatum of aged animals, an effect not reversed by NGF treatment. In contrast, NGF in young animals enhanced striatal CAT activity on the non-lesioned side by 22.2%.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cholinergic marker deficits induced by lesions of the nucleus basalis of Meynert are attenuated by nerve growth factor in young, but not in aged, F344 rats. 850 14

We compared the etiology and prognosis of liver cirrhosis in patients age 60 and older with that of patients under age 60 during the 1980s (1981-89, n = 207). Non-A, non-B hepatitis (NANB) was significantly more prevalent in the elderly (p < 0.05), and the mean age of NANB and alcoholic cirrhosis (Alc) were significantly older than those with hepatitis B virus (HBV) (p < 0.05). Evaluation using hepatitis C virus (HCV) antibody also revealed significantly higher mean age of HCV (p < 0.05). Male patient was predominant in the younger patients than in the elderly patients. (M/F = 2.94 and 1.33, respectively) The estimated 5-year survival rate was 73.1% in the younger patients and 60.2% in the elderly patients (p < 0.05). Multivariate analysis revealed that male sex, a lower serum albumin level, and the presence of the encephalopathy were significantly associated with poor prognosis in the elderly, while a lower serum cholinesterase level and a higher indocyanin green retention rate at 15 minutes (ICGR15) were significantly associated with poor prognosis in younger patients. However, causes of deaths were not significantly different between the younger patients and the elderly patients, the proportion of deaths unrelated to liver disease predominated in the elderly patients. Thus, the etiology and the prognostic factors of liver cirrhosis in elderly patients differ from those in younger patients.
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PMID:Etiology and prognosis of liver cirrhosis in elderly patients. 856 28

Epidemiological surveys indicate an inverse relationship between cancer occurrence and serum cholesterol. Low serum cholesterol might be either a risk factor for cancer or the effect of factors associated with cancer itself, such as biological properties of malignant cells, tumor mass, and poor nutritional status. We have measured serum cholesterol in 975 selected patients admitted to our hospital; 496 (272 males, 224 females) had solid tumors and 479 (253 males, 226 females) had non-neoplastic diseases. Serum cholesterol was positively correlated with body mass index, serum albumin, hemoglobin, and cholinesterase in both cancer and non-cancer subjects. Cholesterol was significantly lower in cancer patients than in age- and sex-matched non-cancer subjects. After adjustment for nutritional variables (analysis of covariance), the difference in cholesterol level between cancer and non-cancer subjects lost statistical significance in all but patients with tumors of the upper gastrointestinal tract. No difference was found in adjusted mean serum cholesterol between cancer patients subdivided according to the extension of the tumor was defined by the TNM system. In patients with solid tumors, serum cholesterol seems to be more related to the nutritional status than the presence and extension of cancer.
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PMID:Serum cholesterol levels in patients with cancer. Relationship with nutritional status. 873 54

A survival analysis was carried out based on the data of 190 male patients with alcoholic liver cirrhosis (Child A: 82.2%; Child B: 17.8%). Patients (mean age: 49.6 +/- 7.1 years) were examined during the period 1983-1990. Censoring in May 1993 was based on the recordings of the "Rentenversicherungsanstalten". There were no "drop-outs". During follow-up (mean: 4.2 years) 64 (33.7%) of the patients died. 13 potential prognostic variables were examined individually by drawing Kaplan-Meier curves and performing log-rank tests. Portal pressure, determined during hepatic vein catheterization as hepatic vein pressure gradient HVPG (P), size of esophageal varices, serum bilirubin, serum albumin, prothrombin time (Quick), thromboplastin time (PTT), cholinesterase (ChE) and Child scores were correlated to survival (p < 0.05), whereas age, gamma GT, IgA, drinking habits and additional diagnoses were not. A multivariate Cox regression analysis stepwise eliminated all but three variables: ChE, albumin and variceal size were included in the prognostic index PI of the final model. The usefulness of the model was tested by a cross validation method. No significant difference was found between estimated and observed survivorship functions. To compare the PI of the Cox model with Child's scores, ROC curves of sensitivity and specificity of predicting death within one, three and five years were constructed. Better prognostic efficiency was indicated for PI. Because ChE, albumin and the size of varices are determined as a routine in our clinic, we consider the construction of PI an advisable alternative to Child's classification.
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PMID:Survival in alcoholic liver cirrhosis: prognostic value of portal pressure, size of esophageal varices and biochemical data. Comparison with Child classification. 877 35


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