No abstract

Cross-linking of surface immunoglobulin (Ig) receptors on human B cells leads to the activation of a tyrosine kinase. The activated tyrosine kinase subsequently phosphorylates a number of substrates, including phospholipase C-gamma. This enzyme breaks down phosphoinositol bisphosphate to form two intracellular messengers, diacylglycerol and inositol 1,4,5-trisphosphate, leading to the activation of protein kinase C and the release of intracellular Ca2+ respectively. We have used h.p.l.c. and flow cytometry to measure accurately the inositol phosphate turnover and Ca2+ release in anti-Ig-stimulated human B cells. In particular, we have examined the effect of dose of the cross-linking antibody on the two responses. The identity of putative messenger inositol phosphates has been verified by structural analysis, and the amounts of both inositol phosphates and Ca2+ present have been quantified. In the Ramos Burkitt lymphoma, which is very sensitive to stimulus through its Ig receptors, both inositol phosphate production and Ca2+ release were found to be related to the dose of anti-Ig antibody applied. This suggests that phospholipase C-mediated signal transduction in human B cells converts the degree of cross-linking of the immunoglobulin receptor quantitatively into intracellular signals.

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The search for sources of animal feed has been well-regarded for farmers. In spite of this, the objective of this study was to show the thermal, physical and chemical properties of earthworms flour from Eisenia andrei for supplementary food for animals. The species was studied by simultaneous thermogravimetric analysis, differential scanning calorimetry, combustion calorimetry, moisture, ash, fat, protein, carbohydrate and fibre analysis. The samples were dried, ground, screened and stored in suitable vials. After the analysis of physical and chemical characterization, it was possible to verify that E. andrei flour presents higher calorific power and levels of protein, fiber, carbohydrate, essential metals and low fat. It can be a promising product as an ideal alternative protein source for better growth performance of animals.