Thiamine deficiency in hepatitis C virus and alcohol-related liver diseases.

Thiamine deficiency is a common feature in chronic alcoholic patients, and its pathophysiology remains poorly understood. Until now, thiamine deficiency has been considered to be mainly the result of alcoholism irrespective of the underlying liver disease. The aims of the study were to compare the prevalence of thiamine deficiency in alcohol- and hepatitis C virus-(HCV-) related cirrhosis and in patients with chronic hepatitis C without cirrhosis.

Determination of tryptophan and its kynurenine pathway metabolites in human serum by high-performance liquid chromatography with simultaneous ultraviolet and fluorimetric detection.

An isocratic reversed-phase high-performance liquid chromatographic method for the simultaneous determination of tryptophan and four metabolites of the kynurenine pathway (kynurenine, 3-hydroxykynurenine, kynurenic acid and 3-hydroxyanthranilic acid) in human serum is described. This new method, which uses both isocratic elution and two on-line connected programmable ultraviolet and spectrofluorimetric detectors, allows the determination of these metabolites, in the physiological ranges, with satisfying specificity and sensitivity within 30 min.

[Beta-2 microglobulin in cerebrospinal fluid in neurology].

Objectives: beta 2-microglobulin (beta 2-m) is a small molecular weight protein (11 800 Daltons) which can transudate into the cerebrospinal fluid (CSF) in the same manner than albumin. Intrathecal synthesis is a sign of local immuno-stimulation and is correlated with immunoglobulin G. The aim of this study was to ascertain the relationship between beta 2-microglobulin levels in the CSF and neurological diseases.

Simultaneous determination of retinyl esters and retinol in human livers by reversed-phase high-performance liquid chromatography.

A high-performance liquid chromatographic method for the simultaneous determination of retinol and retinyl esters in human liver samples is presented. The free retinol and the prevalent retinyl esters (retinyl palmitate, oleate and stearate) are resolved within less than 30 min, using an octasilyl (C8)-substituted column and an isocratic elution with methanol-water as mobile phase. This method allows to determine in duplicate all retinyl ester concentrations in small liver samples (3-10 mg of fresh tissue).