Application of linear discriminant analysis to the biochemical and haematological differentiation of opiate addicts from healthy subjects: a case-control study.

OBJECTIVE: Biochemical and haematological parameters of nutritional interest were determined in the serum of opiate addicts in order to compare them with those obtained in healthy subjects. Linear discriminant analysis was applied for the differentiation of the opiate addicts. SUBJECTS: Sera of 106 opiate addicts in detoxification treatment (n=19) or in Methadone Maintenance Treatment Program (MMTP) (n=87) were studied. DESIGN: : The determination of classical biochemical and haematological parameters in blood samples was carried out using standardized methods. Determination of retinol and alpha-tocopherol was carried out by high-performance liquid chromatography with diode-array detector. Folic acid and vitamin B(12) were determined using competitive binding techniques. Minerals were determined by flame emission spectrometry (Na and K) and atomic absorption spectrometry with air-acetylene flame (Ca, Mg, Fe, Cu and Zn) or with hydride generation (Se). Phosphorous was determined using a colorimetric method with ammonium molibdate. All statistical analyses were performed by means of the SPSS version 10.0 software for Windows. RESULTS: Stepwise linear discriminant analysis simplified the system to the following variables: Na, K, Mg, number of leucocytes, triglycerides, GPT, glucose, albumin, retinol and folic acid; and 90.1% (86.4% after crossvalidation) of correct classification was obtained. Representing the first and second discriminant functions, the control groups were well separated from opiate addicts. CONCLUSIONS: Applying linear discriminant analysis on several biochemical and haematological parameters, the opiate addicts could clearly be differentiated from the control individuals, and a tendency to differentiate the opiate addicts in MMTP and in detoxification treatment was observed.

Fast determination of retinol and alpha-tocopherol in plasma by LC.

A fast, selective and economical method for the determination of retinol and alpha-tocopherol is presented. Both vitamins are separated by high-performance liquid chromatography (HPLC) in less than 4 min using an isocratic elution with methanol. The robustness of the method was checked in real samples, obtaining relative standard deviation lower than 3%. The described method was satisfactorily applied to serum samples proceeding of patients enrolled in a METHADONE maintenance treatment program. The retinol concentrations in the serum of these patients fell into the normal interval of concentrations; however, the serum alpha-tocopherol contents were higher than the normal values.

[Cytometric study of colonic tumors in a model of experimental colonic cancer. Impact of the diet]. / Estudio citométrico de tumores colónicos en un modelo de cáncer de colon experimental. Influencia de la dieta.

Butyrate is a short chain fatty acid, made up of four carbon atoms. Along with acetate and propionate, they are the main volatile fatty acids formed by the microbial fermentation of the carbohydrates of dietary fibre in the colon, mainly in the caecum. Additionally, they acidify the intracolonic pH, and they play an important role in the regulation of the absorption of water and sodium. On the other hand, they are, especially butyrate, preferred by the colon cell, as sources of energy alternative to glucose. Besides this, butyrate, in cellular cultures, is a known antineoplasic agent which is characterized by doubling the cellular duplication time for cells in the G1 phase, it increases the activity of certain enzymes, it stimulates the effects of interferon, it modifies the morphology of the cells, which in some cases leads to the reversion of the characteristic transformations of the cancerous cells, and it produces alterations in the chromatin, the nucleoli, elements of the cytoskeleton and the Golgi apparatus. Even though it is not known how it causes these actions, it is thought that the acetylization of histones which it produces, may be an important mechanism. We analyzed the effect of this substance in a colonic carcinogenesis model in Sprague-Dawley rats, in which the tumors were induced with the alkylating agent 1,2-dimethylhydrazide, observing the cytometric pattern of the tumors, and the possible differences between both groups. In one of them, sodium butyrate was continuously infused by means of a intrathecal catheter at a rhythm of 1.5 ml/hour during the tumoral induction which lasted four weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative analysis of the zeta-crystallin/quinone reductase gene in guinea pig and mouse.

zeta-Crystallin is a novel nicotinamide adenine dinucleotide phosphate:quinone reductase, present at enzymatic levels in various tissues of different species, which is highly expressed in the lens of some hystricomorph rodents and camelids. We report here the complementary DNA (cDNA) cloning of zeta-crystallin from liver libraries in guinea pig (Cavia porcellus), where zeta-crystallin is highly expressed in the lens, and in the laboratory mouse (Mus musculus), where expression in the lens occurs only at enzymatic levels. A 5' untranslated sequence different from the one previously reported for the guinea pig lens cDNA was found in these clones. We also report the isolation of genomic clones including the complete guinea pig zeta-crystallin gene and the 5' region of this gene in mouse. These results show the presence of two promoters in the guinea pig zeta-crystallin gene, one responsible for expression at enzymatic levels and the other responsible for the high expression in the lens. The guinea pig lens promoter is not present in the mouse gene. This is the first example in which the recruitment of an enzyme as a lens crystallin can be explained by the acquisition of an alternative lens-specific promoter.

The transcripts of zeta-crystallin, a lens protein related to the alcohol dehydrogenase family, are altered in a guinea-pig hereditary cataract.

Zeta-Crystallin, a major component of the guinea-pig lens proteins, is distantly related to the enzymes of the zinc-containing alcohol dehydrogenase family (ADH). Analysis of the structural similarities between zeta-crystallin and ADH reveals that while characteristics important in maintaining the tertiary structure of the molecule appear conserved, the amino acids binding the catalytic zinc atom are absent in zeta-crystallin. Significantly, zeta-crystallin does not have ADH activity. Previous studies showed that the zeta-crystallin protein is modified in the lens of guinea-pigs affected with an autosomal dominant hereditary cataract. We have further investigated the molecular origin of the lens defect by examining the steady-state levels of zeta-crystallin transcripts in normal and mutant eyes. Our data indicate that no normal zeta-crystallin mRNA is present in the lens of the homozygous animals; instead, a cross-hybridizing lower molecular weight mRNA is detected at significantly reduced concentrations. Heterozygous lenses exhibit both mRNA species.