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H. Furthermore (h + furthermore)
Selected AbstractsBSc2118 is a novel proteasome inhibitor with activity against multiple myelomaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 2 2010Jan Sterz Abstract Objectives:, The ubiquitin,proteasome system emerged as a new therapeutic target in cancer treatment. The purpose of this study was to elucidate the effects of the novel proteasome inhibitor BSc2118 on t(4;14) positive and negative multiple myeloma (MM) cells and normal peripheral blood mononuclear cells (PBMNC). Methods:, Human MM cell lines OPM-2, RPMI-8226, and U266 and primary MM cells from bone marrow aspirates were exposed to BSc2118. Cytotoxicity levels were evaluated using the MTT-test. BSc2118-induced apoptosis was analyzed by annexin-V assay. Further methods used included proteasomal activity determination, cell cycle analysis, western blot, and transcription factor assays. Results:, In OPM-2, RPMI-8226, U266 cell lines and primary MM cells, BSc2118 caused dose-dependent growth inhibitory effects. After 48 h, dose-dependent apoptosis occurred both in cell lines and primary myeloma cells irrespective of t(4;14). A significant G2-M cell cycle arrest occurred after 24 h. Furthermore, we observed a marked inhibition of intracellular proteasome activity, an increase in intracellular p21 levels, and an inhibition of NF-,B activation. The toxicity against PBMNC remained low, suggesting a broad therapeutic range of this agent. Conclusion:, Taken together, BSc2118 shows significant antimyeloma activity and may be considered as a promising agent in cancer drug development. [source] PROTECTIVE EFFECT OF LYSOSTAPHIN FROM STAPHYLOCOCCUS SIMULANS AGAINST GROWTH OF STAPHYLOCOCCUS AUREUS IN MILK AND SOME OTHER FOOD PRODUCTSJOURNAL OF FOOD SAFETY, Issue 3 2007PIOTR SZWEDA ABSTRACT The effect of lysostaphin from Staphylococcus simulans expressed in Escherichia coli TOP10 strain on Staphylococcus aureus used for inoculation of milk, ground pork and mayonnaise salad was investigated. The populations of this pathogen in ultrahigh-temperature milk preserved at 4C by lysostaphin added up to concentrations of 1.5 or 3.0 µg/mL were reduced by 0.73 and 0.92 log(cfu/mL) in control samples without enzyme addition. The protective influence of lysostaphin was diminished in case of milk storage (20C) prolonged up to 24 h. Furthermore, a final reduction level by 0.92 log(cfu/mL) was achieved after 24 h of pork storage. The smaller and more dependent on enzyme concentration inactivation of S. aureus was observed in the case of the mayonnaise salad, and it led to the conclusion that some food components or proteolytic enzymes originating from other bacteria caused lysostaphin inactivation. [source] Uncoupling brassinosteroid levels and de-etiolation in peaPHYSIOLOGIA PLANTARUM, Issue 2 2002Gregory M. Symons The suggestion that brassinosteroids (BRs) have a negative regulatory role in de-etiolation is based largely on correlative evidence, which includes the de-etiolated phenotypes of, and increased expression of light-regulated genes in, dark-grown mutants defective in BR biosynthesis or response. However, we have obtained the first direct evidence which shows that endogenous BR levels in light-grown pea seedlings are increased, not decreased, in comparison with those grown in the dark. Similarly, we found no evidence of a decrease in castasterone (CS) levels in seedlings that were transferred from the dark to the light for 24 h. Furthermore, CS levels in the constitutively de-etiolated lip1 mutant are similar to those in wild-type plants, and are not reduced as is the case in the BR-deficient lkb plants. Unlike lip1, the pea BR-deficient mutants lk and lkb are not de-etiolated at the morphological or molecular level, as they exhibit neither a de-etiolated phenotype or altered expression of light-regulated genes when grown in the dark. Similarly, dark-grown WT plants treated with the BR biosynthesis inhibitor, Brz, do not exhibit a de-etiolated phenotype. In addition, analysis of the lip1lkb double mutant revealed an additive phenotype indicative of the two genes acting in independent pathways. Together these results strongly suggest that BR levels do not play a negative-regulatory role in de-etiolation in pea. [source] Comparison between propidium iodide and 7-amino-actinomycin-D for viability assessment during flow cytometric analyses of the human sperm acrosomeANDROLOGIA, Issue 1 2010N. Falzone Summary Evaluation of the acrosome reaction can shed light on the fertilising competence of spermatozoa. To eliminate false-positive results when evaluating the acrosome status of human sperm cells, two viability probes propidium iodide (PI) and 7-amino-actinomycin D (7-AAD) were compared for their ability to stain nonviable cells post-fixation and permeabilisation. Both the mean fluorescence and % dead cells differed significantly with time (P < 0.0001). Unlike PI, 7-AAD did not leach from cells and fluorescence remained stable for up to 4 h. Furthermore, 7-AAD proved to be a proficient marker to exclude dead sperm cells during flow cytometric evaluation of ionophore-induced acrosome reaction. [source] Design of a cytochrome P450BM3 reaction system linked by two-step cofactor regeneration catalyzed by a soluble transhydrogenase and glycerol dehydrogenaseBIOTECHNOLOGY PROGRESS, Issue 5 2009Tsuyoshi Mouri Abstract A cytochrome P450BM3-catalyzed reaction system linked by a two-step cofactor regeneration was investigated in a cell-free system. The two-step cofactor regeneration of redox cofactors, NADH and NADPH, was constructed by NAD+ -dependent bacterial glycerol dehydrogenase (GLD) and bacterial soluble transhydrogenase (STH) both from Escherichia coli. In the present system, the reduced cofactor (NADH) was regenerated by GLD from the oxidized cofactor (NAD+) using glycerol as a sacrificial cosubstrate. The reducing equivalents were subsequently transferred to NADP+ by STH as a cycling catalyst. The resultant regenerated NADPH was used for the substrate oxidation catalyzed by cytochrome P450BM3. The initial rate of the P450BM3-catalyzed reaction linked by the two-step cofactor regeneration showed a slight increase (approximately twice) when increasing the GLD units 10-fold under initial reaction conditions. In contrast, a 10-fold increase in STH units resulted in about a 9-fold increase in the initial reaction rate, implying that transhydrogenation catalyzed by STH was the rate-determining step. In the system lacking the two-step cofactor regeneration, 34% conversion of 50 ,M of a model substrate (p-nitrophenoxydecanoic acid) was attained using 50 ,M NADPH. In contrast, with the two-step cofactor regeneration, the same amount of substrate was completely converted using 5 ,M of oxidized cofactors (NAD+ and NADP+) within 1 h. Furthermore, a 10-fold dilution of the oxidized cofactors still led to approximately 20% conversion in 1 h. These results indicate the potential of the combination of GLD and STH for use in redox cofactor recycling with catalytic quantities of NAD+ and NADP+. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Protective Effect of Viral Homologues of bcl-2 on Hybridoma Cells under Apoptosis-Inducing ConditionsBIOTECHNOLOGY PROGRESS, Issue 1 2003Joaquim Vives Targets for metabolic engineering have been identified in a hybridoma cell line to make it more robust in culture toward potential limitations inducing apoptosis. The cells were genetically modified with plasmids harboring endogenous bcl-2 gene and also with viral Bcl-2 homologues, particularly ksbcl-2 and bhrf-1 genes. When cells were exposed to apoptosis-inducing conditions (i.e., glutamine-free medium), the control cells exhibited a decrease in viable cell number within the first 12 h, whereas, for the bcl-2 and ksbcl-2 transfected cell cultures, the viable cell number did not exhibit any clear decrease until after 60 h. Furthermore, hybridoma cells expressing the viral homologue bhrf-1 were even more resistant to cell death, showing a decrease in viability of only 50% at 72 h of culture in glutamine-deprived medium, substantially lower than the 90% viability decrease observed for the control culture. In addition, and most relevant for further bioprocess applications, the cells genetically modified could be brought back to growth conditions even after being exposed to glutamine-deprived conditions during a significant time window, up to 72 h. [source] | |||||||||||||