A convenient route was envisaged toward the synthesis of dihydrochelerythrine (DHCHL), 4 by intramolecular Suzuki coupling of 2-bromo-N-(2-bromobenzyl)-naphthalen-1-amine derivative 5 via in situ generated arylborane. This compound was converted to (±)-6-acetonyldihydrochelerythrine (ADC), 3 which was then resolved by chiral prep-HPLC. Efficiency of DHCHL for the stabilization of promoter quadr...

Among the pleiotropic effects of human interferon are the inhibition of viral replication, the activation of natural killer cells, and the inhibition of cellular growth. Oxyphenbutazone, a nonsteroidal antiinflammatory agent, is a potent inhibitor of the antiviral activity of human alpha and beta interferons as determined by cytopathic effect and vesicular stomatitis virus synthesis and release...

Addition of epidermal growth factor to A431 cells results in dramatic changes in cell morphology. Initially the cells form membrane ruffles accompanied by increased actin polymerization, followed by cell rounding. Activation of the tyrosine kinase of the receptor by binding epidermal growth factor leads also to phosphorylation and activation of phospholipase C-gamma 1, a key enzyme in the phosp...

We have previously described anti-epidermal growth factor (EGF) receptor monoclonal antibodies (MAbs) which can block binding of transforming growth factor alpha (TGF-alpha) and EGF to receptors and inhibit activation of receptor tyrosine kinase. Studies with these MAbs involving cell cultures and nude mouse xenografts demonstrated their capacity to inhibit the growth of a variety of tumor cell...

Human T cell leukemia virus (HTLV), which we previously called adult T cell leukemia virus (ATLV), is a possible causative agent of human adult T cell leukemia (ATL) (1). Since the HTLV genome was demonstrated not to contain a typical v-onc gene (2) and the HTLV proviral genome is integrated into random sites in cellular DNA of leukemia cells in each ATL patient (3), the mechanism of HTLV-induc...

the lung cancer is one of the most dangerous cancers and is also the leading cause of cancer death worldwide, accounting for about 1.3 million deaths annually. however in clinical practice, lung cancer therapies commonly do with chemotherapy, although it is hard because the lung cancer may progress to metastasis stage. the metastasis of lung cancer is highly dependent of expression of matrix me...

background- cd24 is a cell adhesion molecule that has been implicated in metastatic tumor progression cells. our aim was clarify correlation between cd24 expression and camp:cgmp ratio in murine colorectal cancer cell line (ct26) after using cholera toxin. materials and methods- the ct26 cells were cultured in microtubes for assaying camp and cgmp; also the cells were cultured in flasks for ass...

the sporozoites of theileria annulata invade bovine mhc ii cells, where they differentiate into schizonts. the later can immortalize and induce fundamental changes in their host cells. live attenuated vaccine is an important way of controlling t. annulata infection of cattle. production is by prolonged cultivation of macroschizont-infected cells. the mechanisms underlying this transformation ar...

methods s. cerevisiae was cultured and then disrupted by sonication. after centrifugation, the harvested supernatant was considered to be a cytoplasmic extract. the protein concentration was determined by the biuret method and the extract was diluted to concentrations of 500, 1000, and 2000 µg protein/ml. the frequencies of apoptosis and necrosis were assessed in extract-treated k562 cells by e...