Analysis of clinical ostreid herpesvirus 1 (Malacoherpesviridae) specimens by sequencing amplified fragments from three virus genome areas

Although there are a number of ostreid herpesvirus 1 (OsHV-1) variants, it is expected that the true diversity of this virus will be known only after the analysis of significantly more data. To this end, we analyzed 72 OsHV-1 "specimens" collected mainly in France over an 18-year period, from 1993 to 2010. Additional samples were also collected in Ireland, the United States, China, Japan, and New Zealand. Three virus genome regions (open reading frame 4 [ORF4], ORF35, -36, -37, and -38, and ORF42 and -43) were selected for PCR analysis and sequencing. Although ORF4 appeared to be the most polymorphic genome area, distinguishing several genogroups, ORF35, -36, -37, and -38 and ORF42 and -43 also showed variations useful in grouping subpopulations of this virus.     

Alternative splicing regulates targeting of malate dehydrogenase in Yarrowia lipolytica

Alternative pre-mRNA splicing is a major mechanism contributing to the proteome complexity of most eukaryotes, especially mammals. In less complex organisms, such as yeasts, the numbers of genes that contain introns are low and cases of alternative splicing (AS) with functional implications are rare. We report the first case of AS with functional consequences in the yeast Yarrowia lipolytica. The splicing pattern was found to govern the cellular localization of malate dehydrogenase, an enzyme of the central carbon metabolism. This ubiquitous enzyme is involved in the tricarboxylic acid cycle in mitochondria and in the glyoxylate cycle, which takes place in peroxisomes and the cytosol. In Saccharomyces cerevisiae, three genes encode three compartment-specific enzymes. In contrast, only two genes exist in Y. lipolytica. One gene (YlMDH1, YALI0D16753g) encodes a predicted mitochondrial protein, whereas the second gene (YlMDH2, YALI0E14190g) generates the cytosolic and peroxisomal forms through the alternative use of two 3'-splice sites in the second intron. Both splicing variants were detected in cDNA libraries obtained from cells grown under different conditions. Mutants expressing the individual YlMdh2p isoforms tagged with fluorescent proteins confirmed that they localized to either the cytosolic or the peroxisomal compartment.     

LTP inhibits LTD in the hippocampus via regulation of GSK3beta

Glycogen synthase kinase-3 (GSK3) has been implicated in major neurological disorders, but its role in normal neuronal function is largely unknown. Here we show that GSK3beta mediates an interaction between two major forms of synaptic plasticity in the brain, N-methyl-D-aspartate (NMDA) receptor-dependent long-term potentiation (LTP) and NMDA receptor-dependent long-term depression (LTD). In rat hippocampal slices, GSK3beta inhibitors block the induction of LTD. Furthermore, the activity of GSK3beta is enhanced during LTD via activation of PP1. Conversely, following the induction of LTP, there is inhibition of GSK3beta activity. This regulation of GSK3beta during LTP involves activation of NMDA receptors and the PI3K-Akt pathway and disrupts the ability of synapses to undergo LTD for up to 1 hr. We conclude that the regulation of GSK3beta activity provides a powerful mechanism to preserve information encoded during LTP from erasure by subsequent LTD, perhaps thereby permitting the initial consolidation of learnt information.     

Measuring the Outcome of Biomedical Research: A Systematic Literature Review

Background

There is an increasing need to evaluate the production and impact of medical research produced by institutions. Many indicators exist, yet we do not have enough information about their relevance. The objective of this systematic review was (1) to identify all the indicators that could be used to measure the output and outcome of medical research carried out in institutions and (2) enlist their methodology, use, positive and negative points.

Methodology

We have searched 3 databases (Pubmed, Scopus, Web of Science) using the following keywords: [Research outcome* OR research output* OR bibliometric* OR scientometric* OR scientific production] AND [indicator* OR index* OR evaluation OR metrics]. We included articles presenting, discussing or evaluating indicators measuring the scientific production of an institution. The search was conducted by two independent authors using a standardised data extraction form. For each indicator we extracted its definition, calculation, its rationale and its positive and negative points. In order to reduce bias, data extraction and analysis was performed by two independent authors.

Findings

We included 76 articles. A total of 57 indicators were identified. We have classified those indicators into 6 categories: 9 indicators of research activity, 24 indicators of scientific production and impact, 5 indicators of collaboration, 7 indicators of industrial production, 4 indicators of dissemination, 8 indicators of health service impact. The most widely discussed and described is the h-index with 31 articles discussing it.

Discussion

The majority of indicators found are bibliometric indicators of scientific production and impact. Several indicators have been developed to improve the h-index. This indicator has also inspired the creation of two indicators to measure industrial production and collaboration. Several articles propose indicators measuring research impact without detailing a methodology for calculating them. Many bibliometric indicators identified have been created but have not been used or further discussed.     

Kin recognition and co‐operative foraging in Drosophila melanogaster larvae

A long‐standing goal for biologists and social scientists is to understand the factors that lead to the evolution and maintenance of co‐operative behaviour between conspecifics. To that end, the fruit fly, Drosophila melanogaster, is becoming an increasingly popular model species to study sociality; however, most of the research to date has focused on adult behaviours. In this study, we set out to examine group‐feeding behaviour by larvae and to determine whether the degree of relatedness between individuals mediates the expression co‐operation. In a series of assays, we manipulated the average degree of relatedness in groups of third‐instar larvae that were faced with resource scarcity, and measured the size, frequency and composition of feeding clusters, as well as the fitness benefits associated with co‐operation. Our results suggest that larval D. melanogaster are capable of kin recognition (something that has not been previously described in this species), as clusters were more numerous, larger and involved more larvae, when more closely related kin were present in the social environment. These findings are discussed in the context of the correlated fitness‐associated benefits of co‐operation, the potential mechanisms by which individuals may recognize kin, and how that kinship may play an important role in facilitating the manifestation of this co‐operative behaviour.     

Meiotic cohesin STAG3 is required for chromosome axis formation and sister chromatid cohesion

The cohesin complex is essential for mitosis and meiosis. The specific meiotic roles of individual cohesin proteins are incompletely understood. We report in vivo functions of the only meiosis‐specific STAG component of cohesin, STAG3. Newly generated STAG3‐deficient mice of both sexes are sterile with meiotic arrest. In these mice, meiotic chromosome architecture is severely disrupted as no bona fide axial elements (AE) form and homologous chromosomes do not synapse. Axial element protein SYCP3 forms dot‐like structures, many partially overlapping with centromeres. Asynapsis marker HORMAD1 is diffusely distributed throughout the chromatin, and SYCP1, which normally marks synapsed axes, is largely absent. Centromeric and telomeric sister chromatid cohesion are impaired. Centromere and telomere clustering occurs in the absence of STAG3, and telomere structure is not severely affected. Other cohesin proteins are present, localize throughout the STAG3‐devoid chromatin, and form complexes with cohesin SMC1β. No other deficiency in a single meiosis‐specific cohesin causes a phenotype as drastic as STAG3 deficiency. STAG3 emerges as the key STAG cohesin involved in major functions of meiotic cohesin.     

Correct patterning of the primitive streak requires the anterior visceral endoderm

Anterior-posterior axis specification in the mouse requires signalling from a specialised extra-embryonic tissue called the anterior visceral endoderm (AVE). AVE precursors are induced at the distal tip of the embryo and move to the prospective anterior. Embryological and genetic analysis has demonstrated that the AVE is required for anterior patterning and for correctly positioning the site of primitive streak formation by inhibiting Nodal activity. We have carried out a genetic ablation of the Hex-expressing cells of the AVE (Hex-AVE) by knocking the Diphtheria toxin subunit A into the Hex locus in an inducible manner. Using this model we have identified that, in addition to its requirement in the anterior of the embryo, the Hex-AVE sub-population has a novel role between 5.5 and 6.5dpc in patterning the primitive streak. Embryos lacking the Hex-AVE display delayed initiation of primitive streak formation and miss-patterning of the anterior primitive streak. We demonstrate that in the absence of the Hex-AVE the restriction of Bmp2 expression to the proximal visceral endoderm is also defective and expression of Wnt3 and Nodal is not correctly restricted to the posterior epiblast. These results, coupled with the observation that reducing Nodal signalling in Hex-AVE ablated embryos increases the frequency of phenotypes observed, suggests that these primitive streak patterning defects are due to defective Nodal signalling. Together, our experiments demonstrate that the AVE is not only required for anterior patterning, but also that specific sub-populations of this tissue are required to pattern the posterior of the embryo.     

Online video-based resistance training improves the physical capacity of junior basketball athletes

ABSTRACT: Klusemann, MJ, Pyne, DB, Fay, T, and Drinkwater, EJ. Online Video-Based Resistance Training Improves the Physical Capacity of Junior Basketball Athletes. J Strength Cond Res 26(10): 2677-2684, 2012-Junior basketball athletes require a well-designed resistance training program to improve their physical development. Lack of expert supervision and resistance training in junior development pathways may be overcome by implementing an online video-based program. The aim of this study was to compare the magnitude of improvement (change) in physical performance and strength and functional movement patterns of junior basketball athletes using either a fully supervised or an online video-based resistance training program. Thirty-eight junior basketball athletes (males, n = 17; age, 14 ± 1 year; height, 1.79 ± 0.10 m; mass, 67 ± 12 kg; females, n = 21; age, 15 ± 1 year; height, 1.70 ± 0.07 m; mass, 62 ± 8 kg) were randomly assigned into a supervised resistance training group (SG, n = 13), video training group (VG, n = 13) or control group (CG, n = 12) and participated in a 6-week controlled experimental trial. Pre- and posttesting included measures of physical performance (20-m sprint, step-in vertical jump, agility, sit and reach, line drill, and Yo-Yo intermittent recovery level 1), strength (15 s push-up and pull-up), and functional movement screening (FMS). Both SG and VG achieved 3-5% ± 2-4% (mean ± 90% confidence limits) greater improvements in several physical performance measures (vertical jump height, 20-m sprint time, and Yo-Yo endurance performance) and a 28 ± 21% greater improvement in push-up strength compared with the CG. The SG attained substantially larger gains in FMS scores over both the VG (12 ± 10%) and CG (13 ± 8%). Video-based training appears to be a viable option to improve physical performance and strength in junior basketball athletes. Qualified supervision is recommended to improve functional movement patterns in junior athletes.