Chromium uptake bySaccharomyces cerevisiae and isolation of glucose tolerance factor from yeast biomass

Fermentations with yeastSaccharomyces cerevisiae in semiaerobic and in static conditions with the addition of chromic chloride into the used molasses medium were analysed. It was proved that the addition of optimal amounts of CrCl₃ into the basal medium enhanced the kinetics of alcohol fermentations. The addition of 200 mg/l CrCl₃ into the medium stimulated both the yeast growth and the ethanol production in all experimental conditions. On the other hand, the results showed that Cr³⁺ ions were incorporated into yeast cells during fermentation. Under these conditions the accumulation of Cr³⁺ ions was performed by yeast cells during the exponential growth phase, and with enriched amounts of 30–45 (μg/g_d.m. of cells. Yeast biomass enriched with chromium ions was extracted with 01 mol/l NH₄OH assuming that the extracts had the glucose tolerance factor (GTF). Then the extracts were passed through a gel-filtration column in order to isolate and purify the GTF. The presence of GTF in the purified fractions was determined by measuring the absorbance at 260 nm. It is evident from the obtained results that the added purified fractions enhanced the rates of CO₂ production as well as the glucose utilization during alcoholic fermentation. As expected, the enhancement of both rates depended on the amounts of extracts added to the fermentation substrate. Thus, it is evident that purified extracts contained the GTF compound, and that Cr³⁺ ions were bonded to the protein molecule.     

Binary Fate Choice between Closely Related Interneuronal Types Is Determined by a Fezf1-Dependent Postmitotic Transcriptional Switch

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Transfer factor prevents relapses in herpes keratitis patients: A pilot study

Transfer Factor is a dialysable moiety obtained from immune lymphocytes. It has been successfully used for the treatment of several viral infections including labial and genital herpes. In the present study, thirty-three patients with low immune response to HSV antigens and suffering from herpes ocular infections were orally treated with HSV-specific transfer factor (TF). Their relapse index was reduced from 20.1 before treatment to 0.51 after TF administration, with only 6/33 patients relapsing. Although this is not a placebo-controlled-randomized study, the results suggest that TF specific for HSV antigens may be efficacious for preventing relapses of ocular herpes infections as has been the case with genital and labial localisations.Abbreviations CMI Cell-mediated immunity - CMV Cytomegalo-virus - EBV Epstein-Barr virus - HIV Human immunodeficiency virus - HK Herpes keratitis - HSV Herpes simplex virus - IRI Individual relapse index - KU Kerato-uveitis - LMT Leucocyte migration test - LST Lymphocyte stimulation test - MIF Migration inhibition factor - RHK Relapsing herpes keratitis - TF Transfer factor