Percutaneous selective thermorhizotomy in the treatment of "essential" trigeminal neuralgia. The importance of lesion selectivity

Results following percutaneous thermorhizotomy for trigeminal neuralgia are described in 111 patients. Recurrences and side effects are more frequent whenever selectivity of the surgical lesion has been imperfect (exceeding the original pain area and causing marked hypoesthesia), and less frequent in the cases with strictly selective lesion.     

Stimulation of enzyme secretion from isolated pancreatic acini by Clostridium difficile toxin B

Exposure of isolated rat pancreatic acini to increasing concentrations (10 ng - 800 ng/ml) of toxin B from Clostridium difficile produced a biphasic effect on the rate of secretion of amylase, trypsinogen, and chymotrypsinogen. Whereas doses of toxin B from 10-30 ng/ml increased enzyme secretion by 15-20%, doses between 30 ng and 60 ng/ml showed a regression of this effect, whereafter the rate of secretion of amylase, trypsinogen, and chymotrypsinogen increased with increasing concentrations of the toxin. Toxin B concentration of 800 ng/ml enhanced amylase, trypsinogen and chymotrypsinogen secretion by 119%, 185% and 195%, respectively, when compared with the basal level. Stimulation of enzyme secretion by toxin B was not affected by the presence of either actinomycin-D or cycloheximide, at a concentration which inhibited acinar RNA or protein synthesis by 80-90%. Although toxin B as well as CCK8, carbachol and secretin by themselves caused significant stimulation in amylase, trypsinogen and chymotrypsinogen secretion from isolated pancreatic acini, toxin B together with either CCK8, carbachol or secretin produced no further augmentation in enzyme secretion than what was observed with the secretagogues alone. It is concluded that toxin B of Cl. difficile exerts a direct effect on pancreatic acinar cells as evidenced by stimulation of enzyme secretion.     

Concentration and distribution pattern of selected micronutrients in preterm and term milk from urban Brazilian mothers during early lactation

The purpose of this study was to assess the concentration and binding pattern of zinc, iron, folate and vitamin B12 in milk of Brazilian women of low socioeconomic status giving birth at term or preterm, during early lactation. Protein, fat, total solids and ash concentrations were also determined. Protein and zinc concentrations decreased significantly as lactation proceeded whereas milk fat and folate increased with the lactation period. Total solids, ash, iron and vitamin B12 remained unchanged. Zinc was present mainly in the whey fraction while less than half of the total iron was present in this fraction, with no significant change due to stage of lactation. Unsaturated folate and vitamin B12 binding capacities and percentage of saturation of the folate binding protein increased with the stage of lactation. The vitamin B12 binding protein was highly unsaturated in all samples. There was no significant difference between term and preterm samples in the parameters investigated. Correlation analysis between milk components indicated significant relationships between total solids and fat, total zinc and whey zinc, folate and total folate binding capacity, unsaturated and total folate binding capacity, and unsaturated and total B12 binding capacity. In general, the nutrient concentrations found in this study are in good agreement with published data on milk composition of women from developed countries, with the possible exceptions of folate, which was lower, and iron, which was higher. The correlation of folate concentration with its binding protein found in this work supports the hypothesis of a regulatory role for folate levels in milk exerted by the folate binding protein in the mammary gland.     

Effects of retinol on proliferation, cell adherence and extracellular matrix synthesis in a liver myofibroblast or lipocyte cell line (GRX).

We have studied the effect of retinol on an established murine cell line (GRX), representative of liver connective tissue cells. This cell line has myofibroblast characteristics; under retinol treatment it is induced into the lipocyte (Ito-cell) phenotype. Retinol decreased the proliferation rate in the entire cell population. It increased cell adherence to the substrate, which was correlated with the increased secretion of fibronectin. Collagen secretion was specifically decreased, whilst the total protein secretion remained stable. Heparan sulphate was decreased in the pericellular compartment, but other glycosaminoglycans were not affected by retinol treatment. Modulations of pericellular components induced by retinol may alter the relations among liver mesenchymal cells, and may be related to vitamin-A-induced modifications of the homoeostasis of hepatic connective tissue and hepatic fibrosis.