A photographic documentation of the development of Antarctic krill (Euphausia superba) from egg to early juvenile

Antarctic krill (Euphausia superba) is a key species in Antarctic marine ecosystems, as well as an important species in the Southern Ocean fishery. Here, we provide the first detailed photographic documentation of embryonic and larval development of Antarctic krill over a 5-month developmental period under controlled laboratory conditions. Developing embryos and larvae were photographed every 3 h and every 5 days, respectively. Our results indicated a developmental time of approximately 6 days for embryos and 138 days for larvae (0.5 °C). This study provided baseline biometry information for future investigations of Antarctic krill development under changing environmental conditions.     

Dependence of Na+-K+ pump current-voltage relationship on intracellular Na+, K+, and Cs+ in rabbit cardiac myocytes

To examine effects of cytosolicNa⁺, K⁺, and Cs⁺ on the voltagedependence of the Na⁺-K⁺ pump, we measuredNa⁺-K⁺ pump current (I_p)of ventricular myocytes voltage-clamped at potentials(V_m) from 100 to +60 mV. Superfusates weredesigned to eliminate voltage dependence at extracellular pump sites.The cytosolic compartment of myocytes was perfused with patch pipette solutions with a Na⁺ concentration ([Na]_pip)of 80 mM and a K⁺ concentration from 0 to 80 mM or withsolutions containing Na⁺ in concentrations from 0.1 to 100 mM and K⁺ in a concentration of either 0 or 80 mM. When[Na]_pip was 80 mM, K⁺ in pipette solutionshad a voltage-dependent inhibitory effect on I_pand induced a negative slope of theI_p-V_m relationship. Cs⁺ in pipette solutions had an effect onI_p qualitatively similar to that ofK⁺. Increases in I_p with increasesin [Na]_pip were voltage dependent. The dielectriccoefficient derived from[Na]_pip-I_p relationships at thedifferent test potentials was 0.15 when pipette solutions included 80 mM K⁺ and 0.06 when pipette solutions were K⁺ free.

     

Relay of Herpes Simplex Virus between Langerhans Cells and Dermal Dendritic Cells in Human Skin

The mechanism by which immunity to Herpes Simplex Virus (HSV) is initiated is not completely defined. HSV initially infects mucosal epidermis prior to entering nerve endings. In mice, epidermal Langerhans cells (LCs) are the first dendritic cells (DCs) to encounter HSV, but it is CD103⁺ dermal DCs that carry viral antigen to lymph nodes for antigen presentation, suggesting DC cross-talk in skin. In this study, we compared topically HSV-1 infected human foreskin explants with biopsies of initial human genital herpes lesions to show LCs are initially infected then emigrate into the dermis. Here, LCs bearing markers of maturation and apoptosis formed large cell clusters with BDCA3⁺ dermal DCs (thought to be equivalent to murine CD103⁺ dermal DCs) and DC-SIGN⁺ DCs/macrophages. HSV-expressing LC fragments were observed inside the dermal DCs/macrophages and the BDCA3⁺ dermal DCs had up-regulated a damaged cell uptake receptor CLEC9A. No other infected epidermal cells interacted with dermal DCs. Correspondingly, LCs isolated from human skin and infected with HSV-1 in vitro also underwent apoptosis and were taken up by similarly isolated BDCA3⁺ dermal DCs and DC-SIGN⁺ cells. Thus, we conclude a viral antigen relay takes place where HSV infected LCs undergo apoptosis and are taken up by dermal DCs for subsequent antigen presentation. This provides a rationale for targeting these cells with mucosal or perhaps intradermal HSV immunization.     

A person-centered exploration of children of immigrants’ social experiences and their school-based well-being

This study aimed to explore commonalities among discrimination, stereotyping, and peer-related social experiences of children of immigrants, and to see if these experiences might relate to children’s school-based well-being. Two age-based cohorts of 294 children and their immigrant parents from Portugal, the Dominican Republic, and Cambodia were interviewed. Person-centered analyses resulted in four unique clusters of children’s social experiences. Notably, children in clusters with positive views of cultural in-group and out-group members also reported positive school-based well-being. Person-centered analyses on parent variables found three clusters based on parents’ ethnic/racial socialization practices. There was no overlap between parent and child clusters, indicating unique profiles between parent socialization and child social experiences within immigrant families. Implications of connections among social experiences and school-based emotional well-being for children of immigrants are discussed.     

A meta-analytic assessment of a Thyroglobulin marker for marbling in beef cattle

A meta-analysis was undertaken reporting on the association between a polymorphism in the Thyroglobulin gene (TG5) and marbling in beef cattle. A Bayesian hierarchical model was adopted, with alternative representations assessed through sensitivity analysis. Based on the overall posterior means and posterior probabilities, there is substantial support for an additive association between the TG5 marker and marbling. The marker effect was also assessed across various breed groups, with each group displaying a high probability of positive association between the T allele and marbling. The WinBUGS program code used to simulate the model is included as an Appendix available online at http://www.edpsciences.org/gse.     

Complete genome sequence of Methanocorpusculum labreanum type strain Z

Methanocorpusculum labreanum is a methanogen belonging to the order Methanomicrobiales within the archaeal kingdom Euryarchaeota. The type strain Z was isolated from surface sediments of Tar Pit Lake in the La Brea Tar Pits in Los Angeles, California. M. labreanum is of phylogenetic interest because at the time the sequencing project began only one genome had previously been sequenced from the order Methanomicrobiales. We report here the complete genome sequence of M. labreanum type strain Z and its annotation. This is part of a 2006 Joint Genome Institute Community Sequencing Program project to sequence genomes of diverse Archaea.