Female reproductive fluid concentrations affect sperm performance of alternative male phenotypes in an external fertilizer

There is growing evidence that the female reproductive fluid (FRF) plays an important role in cryptic female choice through its differential effect on the performance of sperm from different males. In a natural spawning event, the male(s) may release ejaculate closer or further away from the spawning female. If the relative spatial proximity of competing males reflects the female pre-mating preference towards those males, then favoured males will encounter higher concentrations of FRF than unpreferred males. Despite this being a common situation in many external fertilizers, whether different concentrations of FRF can differentially influence the sperm performance of distinct male phenotypes (favoured and unfavoured by the female) remains to be elucidated. Here, we tested this hypothesis using the grass goby (Zosterisessor ophiocephalus), a fish with distinct territorial-sneaker reproductive tactics and female pre-mating preference towards territorial males, that consequently mate in an advantaged position and whose sperm experience higher concentrations of FRF. Our findings revealed a differential concentration-dependent effect of FRF over sneaker and territorial sperm motility only at low concentrations (i.e. at the distance where sneakers typically ejaculate), with increasing FRF concentrations (i.e. close to the eggs) similarly boosting the sperm performance of both sneaker and territorial males. The ability to release sperm close to the eggs is a prerogative of territorials, but FRF can likewise advantage the sperm of those sneakers that are able to get closer, allowing flexibility in the direction of female post-mating choice.     

A Hematogenous Route for Medulloblastoma Leptomeningeal Metastases

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Digital transformation—life cycle assessment of digital services,multifunctional devices and cloud computing

The International Journal of Life Cycle Assessment -     

Association Between the <Emphasis Type="Italic">cfx</Emphasis>A Gene and Transposon Tn<Emphasis Type="Italic">4555</Emphasis> in <Emphasis Type="Italic">Bacteroides distasonis</Emphasis> Strains and Other <Emphasis Type="Italic">Bacteroides</Emphasis> Species

The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.     

The molecular evolution of avian ultraviolet- and violet-sensitive visual pigments

The shortwave-sensitive SWS1 class of vertebrate visual pigments range in lambda(max) from the violet (385-445 nm) to the ultraviolet (UV) (365-355 nm), with UV-sensitivity almost certainly ancestral. In birds, however, the UV-sensitive pigments present in a number of species have evolved secondarily from an avian violet-sensitive (VS) pigment. All avian VS pigments expressed in vitro to date encode Ser86 whereas Phe86 is present in all non-avian ultraviolet sensitive (UVS) pigments. In this paper, we show by site directed mutagenesis of avian VS pigments that Ser86 is required in an avian VS pigment to maintain violet-sensitivity and therefore underlies the evolution of avian VS pigments. The major mechanism for the evolution of avian UVS pigments from an ancestral avian VS pigment is undoubtedly a Ser90Cys substitution. However, Phe86, as found in the Blue-crowned trogon, will also short-wave shift the pigeon VS pigment into the UV whereas Ala86 and Cys86 which are also found in natural avian pigments do not generate short-wave shifts when substituted into the pigeon pigment. From available data on avian SWS1 pigments, it would appear that UVS pigments have evolved on at least 5 separate occasions and utilize 2 different mechanisms for the short-wave shift.     

Interleukin-19 (IL-19) induces heme oxygenase-1 (HO-1) expression and decreases reactive oxygen species in human vascular smooth muscle cells

Heme oxygenase-1 (HO-1) has potent anti-inflammatory activity and recognized vascular protective effects. We have recently described the expression and vascular protective effects of an anti-inflammatory interleukin (IL-19), in vascular smooth muscle cells (VSMC) and injured arteries. The objective of this study was to link the anti-inflammatory effects of IL-19 with HO-1 expression in resident vascular cells. IL-19 induced HO-1 mRNA and protein in cultured human VSMC, as assayed by quantitative RT-PCR, immunoblot, and ELISA. IL-19 does not induce HO-1 mRNA or protein in human endothelial cells. IL-19 activates STAT3 in VSMC, and IL-19-induced HO-1 expression is significantly reduced by transfection of VSMC with STAT3 siRNA or mutation of the consensus STAT binding site in the HO-1 promoter. IL-19 treatment can significantly reduce ROS-induced apoptosis, as assayed by Annexin V flow cytometry. IL-19 significantly reduced ROS concentrations in cultured VSMC. The IL-19-induced reduction in ROS concentration is attenuated when HO-1 is reduced by siRNA, indicating that the IL-19-driven decrease in ROS is mediated by HO-1 expression. IL-19 reduces vascular ROS in vivo in mice treated with TNFα. This points to IL-19 as a potential therapeutic for vascular inflammatory diseases and a link for two previously unassociated protective processes: Th2 cytokine-induced anti-inflammation and ROS reduction.