In this study, a new stigmastane, vernonioside V, was isolated from the ethanol extract of leaves of along with a known flavonoid, cynaroside, and then anti-inflammatory activity of isolated compounds was investigated. The result showed that vernonioside V at concentration of 30 µg/mL strongly inhibited TNFα, IL-6, and IL-8 inflammatory cytokine production. Furthermore, LPS-induced supreoxide generation in Raw 264.
View Article and Find Full Text PDFBackground: RNA interference (RNAi) mediated by small interfering RNAs (siRNAs) or short hairpin RNAs (shRNAs) has become a powerful technique for eukaryotic gene knockdown. siRNA GC-content negatively correlates with RNAi efficiency, and it is of interest to have a convincing mechanistic interpretation of this observation. We here examine this issue by considering the secondary structures for both the target messenger RNA (mRNA) and the siRNA guide strand.
View Article and Find Full Text PDFRNA interference (RNAi) can be an effective antiviral agent; however, overexpression of RNAi can be toxic through competition with the endogenous microRNA (miRNA) machinery. We used rational design to identify highly potent RNAi that is effective at nontoxic doses. A statistical analysis was conducted to pinpoint thermodynamic characteristics correlated with activity.
View Article and Find Full Text PDFThe melting of the coding and non-coding classes of natural DNA sequences was investigated using a program, MELTSIM, which simulates DNA melting based upon an empirically parameterized nearest neighbor thermodynamic model. We calculated T(m) results of 8144 natural sequences from 28 eukaryotic organisms of varying F(GC) (mole fraction of G and C) and of 3775 coding and 3297 non-coding sequences derived from those natural sequences. These data demonstrated that the T(m) vs.
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