“The idea that diversity begets the functioning and stability of ecosystems has been intensely examined in terrestrial habitats, yet these relationships remain poorly studied in the marine realm. Theoretical and empirical work suggest that diversity enhances the stability of communities, but decreases the stability of populations. This is because compensatory dynamics, such as when one 4 species decreases while another increases, stabilise the community as long as species richness increases the variety of responses to the environment. In an observational field study, the temporal variability in species abundance was used as a measure of stability that was compared among 5 intertidal
sites of naturally different species richness. Percent coverage of macrobenthic species was estimated every 6 mo for 2 yr. Stability selleck chemical in total community coverage was a negative but curvilinear function of species richness. In addition, the stability of single populations (averaged
over all species) fluctuated across the species richness gradient, without showing the predicted negative pattern. selleck chemicals llc We found no evidence for increasing compensatory dynamics with increasing species richness, suggesting that the variety of responses to environmental changes was unrelated to diversity. Diversity-stability relationships in natural communities may be more complex than those predicted by theory and manipulative experiments.”
is overexpressed in various types of cancers and is associated with the regulation of the carcinogenic processes. Using RT-PCR, we have identified overexpression of miRNA-106b in various melanoma cell lines (A375, Hs294t, SK-el28, SK-Mel 119, Mel 1241, Mel 1011 and Mel 928) as compared to its expression in normal human epidermal melanocytes (NHEM). The overexpression of miR-106b in melanoma cells (A375, Hs294t) was associated with greater cell proliferation capacity than NHEM. Treatment of A375 and Hs294t cells with anti-miR-106b resulted in inhibition of cell proliferation as well as G1-phase arrest. We determined the effects of grape seed proanthocyanidins (GSPs) on the expression of miRNA-106b and its underlying molecular targets. Treatment of A375 and Hs294t buy Ro 61-8048 cells with GSPs resulted in suppression of the levels of miRNA-106b, cytotoxicity, G1-phase arrest and reactivation of p21/WAF1/Cip1. Dietary GSPs significantly inhibited growth of A375 melanoma cell tumor xenografts in nude mice, which was associated with reduction in the levels of miRNA-106b, tumor cell proliferation and increases in the levels of p21/WAF1/Cip1 protein. These studies suggest that miRNA-106b plays a crucial role in melanoma growth and that GSPs act as an inhibitor of miR-106b thereby blocking melanoma growth in vitro and in vivo models.”
“HEV generally causes a self-limited acute infection and treatment remains supportive.