Decrease in the antioxidant capacity in beverages containing tea extracts during storage.

The aim of this work was to determine antioxidant capacity of beverages containing black, white, and green tea extracts using the photochemiluminescence method, and to monitor its changes based on the storage temperature and time. Samples were stored at two different temperatures (refrigerated at 4°C and laboratory temperature 22°C), analyzed after opening of the original package, and consequently after 4 and 7 days. Results of the antioxidant capacity are expressed as the standard equivalents, that is, ascorbic acid in mmol/L.

Interferon-gamma, but not interferon-alpha, induces SOCS 3 expression in human melanoma cell lines.

The signal transducers and transcription activators (STATs) and their endogenous inhibitors of the suppressors of cytokine signalling (SOCS) family are major proteins harmonizing the transmission of external signals from the surface membrane to target genes in the nucleus. To correlate the induction of SOCS 3 by interferons (IFNs) on messenger RNA and protein levels with STAT 1 phosphorylation in human malignant melanoma cell lines, we used a unique collection of 18 established malignant melanoma cell lines and six human non-malignant normal cells (two melanocytes, two skin keratinocytes and two fibroblasts). IFN-gamma induced SOCS 3 in 83% of melanoma cell lines, whereas IFN-alpha stimulated SOCS 3 expression in only 11% of cases.

Src tyrosine kinase but not activated Ras augments sensitivity to taxanes through apoptosis in human adenocarcinoma cells.

We investigated the mechanistic role of Src and Ras, important oncoproteins implicated in the pathogenesis of many human cancers, in taxane-induced apoptosis using v-src or c-H-ras transfected HAG-1 human gallbladder epithelial cells. Compared with the parental HAG-1 cell line, v-src-transfected HAG/src3-1 cells became 6.0-fold and 7.