Pediatric reference intervals determined in ambulatory and hospitalized children and juveniles.

Objectives: The aim of this study was to determine reference intervals in children and juveniles with nine recently developed and widely used laboratory methods.

Methods: More than 800 ambulatory and hospitalized individuals of the University pediatry were carefully selected according to clinical status and chemical profile in an a posteriori process over a period of two and a half years. The reference group with well-balanced gender proportions and steady age distribution between 1 day and 17 years was subdivided in five age classes.

Quinolinate and kainate facilitate magnesium penetration into brain tissue.

To study the penetration of magnesium ions from blood into brain tissue, magnesium content in serum and hippocampus of normal and of excitotoxically affected rats was estimated after a single subcutaneous injection of magnesium sulphate (600 mg kg-1). In normal rats Mg2+ levels in serum rose from 1 to 6 mM, while that of the hippocampus remained constant, provided the brains were perfused before magnesium measurement. Following unilateral intracerebroventricular injection of the excitotoxic glutamate analogues, quinolinate or kainate acid, Mg2+ levels increased up to 38% on the (unaffected) contralateral side.

Magnesium sulphate subcutaneously injected protects against kainate-induced convulsions and neurodegeneration: in vivo study on the rat hippocampus.

Kainate, an agonist of a unique subclass of glutamate receptors (kainate receptor), was injected intracerebroventricularly in rats to induce convulsive reactions and hippocampal damage in order to model glutamate-mediated brain injury. Rats treated with magnesium sulfate (subcutaneously injected, up to 600 mg/kg) were found to be protected from kainate neurotoxicity depending on the dose and time of application. Results were largely consistent with those obtained previously by using quinolinate as an excitotoxic N-methyl-D-aspartate-receptor agonist.

Correlations between zinc, amino acids and ammonia in liver cirrhosis.

In view of the universal metabolic importance of zinc in the organism, it was the purpose of the present work to determine the concentrations of zinc in serum, of amino acids and ammonia in plasma of patients with liver cirrhosis, and investigate that correlations might exist between these substances. The study involved 18 patients with decompensated liver cirrhosis without coma and eleven with coma. The subjects with normal livers were used as controls.