Aspartate aminotransferase, analysis

Biochemical assays have been employed to measure changes in enzyme levels (e.g., aspartate aminotransferase, lactic dehydrogenase) as an indication of exposure to 1,2-dibromoethane in humans and animals (Albano et al. 1984 Botti et al. 1989 Letz et al. 1984 Van lersel et al. 1988). Decreased sperm counts per ejaculate and increased numbers of sperm with abnormal morphology have also been identified in workers following exposure to 1,2-dibromoethane (Ratcliffe et al. 1987 Wyrobek 1984). In general, these techniques are nonspecific for 1,2-dibromoethane exposure (see Chapter 2). There are no data to indicate whether a biomarker, if available, would be preferred over chemical analysis for monitoring exposure to 1,2-dibromoethane. 

Liver dysfunction. In a 4-year study in 1221 liver dysfunction-free (serum aspartate aminotransferase [AST] and alanine aminotransferase [ALT] <39 lU/L and no medical care for or no past history of liver disease) males aged 35-56 years, was investigated for the association of coffee consumption with the development of increased serum AST and/or ALT activities. From the analysis using the Kaplan-Meier method, the estimated incidence of serum AST and/ or ALT > 40 lU/L, > 50 lU/L, and > 60 lU/ L decreased with an increase in coffee consumption. From the Cox proportional haz-... 

A total of 8388 observations (i.e., concentration values) from 906 patients was used for this analysis. The following covariates were investigated for a possible impact on the PK of cetuximab age, gender, race, BSA, creatinine clearance, bilirubin, alanine aminotransferase, aspartate aminotransferase, concomitant therapy, hepatic status and renal status. 

In a recent study, DR mice exhibited lower inflammatory damage induced by LPS. Balb/c mice were subjected to 40% DR and challenged with 25 pg of LPS. The DR mice had attenuated increases in the proinflammatory cytokines consistent with the lower liver damage characterized by lower plasma alanine aminotranferase (ALT), aspartate aminotransferase (AST) and histopathological analysis. The DR mice also had higher circulating corticosterone, a mediator of antiinflammatory action in DR,... 

ADP AFP ab as ALAT AP ASAT ATP BQ BSA CEH CK CME COD con A CV d D E E EC ECME EDTA EIA /e FAD FET FIA G GOD G6P-DH HBg HCG adenosine diphosphate a-fetoprotein antibody antigen alanine aminotranferase alkaline phosphatase aspartate aminotransferase adenosine triphosphate benzoquinone bovine serum albumin cholesterol ester hydrolase creatine kinase chemically modified electrode cholesterol oxidase concanavalin A coefficient of variation (relative standard deviation) layer thickness diffusion coefficient enzyme potential Enzyme Classification enzyme-chemically modified electrode ethylene diamine tetraacetic acid enzyme immunoassay enzyme loading factor flavin adenine dinucleotide field effect transistor flow injection analysis amplification factor glucose oxidase glucose-6-phosphate dehydrogenase hepatitis B surface antigen human chorionic gonadotropin... 

Sometimes, rather than treating the covariate as a continuous variable, the covariate will be categorized and the categorical variable will be used in the model instead of the original value. For example, de Maat et al. (2002) in a population analysis of nevirapine categorized baseline laboratory markers of hepatic function into dichotomous covariates. Patients were coded as V if their laboratory value was 1.5 times higher than the upper limit of normal and 0 otherwise. Patients with an aspartate aminotransferase 1.5 times higher than normal had a 13% decrease in nevirapine clearance than patients with normal values. 

Fig. 48. Chirality analysis at C-4 of pyridoxamine obtained following reduction of the binary complex of aspartate aminotransferase with NaB H4. It should be noted that at the dehydrohalogenation step only half the reaction will occur via the pathway shown (cf. reaction of 4 Fig. 49).

Fig. 55. Configurational analysis of [4 - H]pyridoxamine obtained by the half-transamination reaction catalysed by the apo protein of aspartate aminotransferase in [ H]H20.

Acute hepatitis mimicking iron overload syndrome was reported in a 35-year-old man who had been taking fo-ti (dose and duration unspecified). Laboratory studies included alanine transferase 2714 U/1 (normal <50 U/1), aspartate aminotransferase 1170 U/1 (normal <50 U/1), AP 137 U/1 (normal <130 U/1), total bilirubin 4.6 mg/dl (normal <1.4 mg/dl), direct bilirubin 3.0 mg/dl (normal <0.4 mg/dl), and ferritin 13,862 ng/ml (normal 8 to 282 ng/ml) and a fasting transferrin saturation of 86% (normal 20% to 60%). Analysis of the herbal supplement identified extracts from fo-ti including the anthraquinones emodin and physcion. The patient recovered after cessation of the herbal products, and liver function tests 4 months after hospitalization were normal (Laird et al. 2008). 

Ezetimibe + a statin The profiles of general safety and tolerability of statin monotherapy and statin+ezetiniibe combination therapy have been accumulated [3,4], A pooled analysis with over 22,000 subjects has confirmed the overall safety and tolerability profiles of ezetimibe added to a statin are generally comparable to statin monotherapy for up to 24 weeks [5]. Although the incidence was low, elevations in liver enzymes were observed more often with ezetimibe-statin combination treatment compared with statin monotherapy (consecutive aspartate aminotransferase (AST) or ALT elevation elevations 3 x upper limit of normal (statin 0.35%, statin + ezetimibe 0.56% p=0.017)). 

As with the other B vitamins that act as coenzymes biochemical assessment of vitamin Bg can, be made by direct chemical analysis of the vitamer or its metabolites, or by functional means. Measurements that have been used are PLP in plasma or red cells, its metabolite 4 PA in urine or plasma, the activity and activation coefficient of the red cell aminotransferases (aspartate and alanine), and the tryptophan load metabolite excretion test. As no single marker adequately reflects status, a combination of these markers olfers the best approach. 

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