Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles

Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ω (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ω global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes

Intra-articular temperatures of the knee in sports – An in-vivo study of jogging and alpine skiing

<p>Abstract</p> <p>Background</p> <p>Up to date, no information exists about the intra-articular temperature changes of the knee related to activity and ambient temperature.</p> <p>Methods</p> <p>In 6 healthy males, a probe for intra-articular measurement was inserted into the notch of the right knee. Each subject was jogging on a treadmill in a closed room at 19°C room temperature and skiing in a ski resort at -3°C outside temperature for 60 minutes. In both conditions, temperatures were measured every fifteen minutes intra-articulary and at the skin surface of the knee. A possible influence on joint function and laxity was evaluated before and after activity. Statistical analysis of intra-articular and skin temperatures was done using nonparametric Wilcoxon's sign rank sum test and Mann-Whitney's-U-Test.</p> <p>Results</p> <p>Median intra-articular temperatures increased from 31.4°C before activity by 2.1°C, 4°C, 5.8°C and 6.1°C after 15, 30, 45 and 60 min of jogging (all p ≤ 0.05). Median intra-articular temperatures dropped from 32.2°C before activity by 0.5°C, 1.9°C, 3.6°C and 1.1°C after 15, 30, 45 and 60 min of skiing (all n.s.). After 60 minutes of skiing (jogging), the median intra-articular temperature was 19.6% (8.7%) higher than the skin surface temperature at the knee. Joint function and laxity appeared not to be different before and after activity within both groups.</p> <p>Conclusion</p> <p>This study demonstrates different changes of intra-articular and skin temperatures during sports in jogging and alpine skiing and suggests that changes are related to activity and ambient temperature.</p

A Deubiquitylating Complex Required for Neosynthesis of a Yeast Mitochondrial ATP Synthase Subunit

The ubiquitin system is known to be involved in maintaining the integrity of mitochondria, but little is known about the role of deubiquitylating (DUB) enzymes in such functions. Budding yeast cells deleted for UBP13 and its close homolog UBP9 displayed a high incidence of petite colonies and slow respiratory growth at 37°C. Both Ubp9 and Ubp13 interacted directly with Duf1 (DUB-associated factor 1), a WD40 motif-containing protein. Duf1 activates the DUB activity of recombinant Ubp9 and Ubp13 in vitro and deletion of DUF1 resulted in the same respiratory phenotype as the deletion of both UBP9 and UBP13. We show that the mitochondrial defects of these mutants resulted from a strong decrease at 37°C in the de novo biosynthesis of Atp9, a membrane-bound component of ATP synthase encoded by mitochondrial DNA. The defect appears at the level of ATP9 mRNA translation, while its maturation remained unchanged in the mutants. This study describes a new role of the ubiquitin system in mitochondrial biogenesis

Annotated checklist of the birds of Brazil by the Brazilian ornithological records committee / Lista comentada das aves do Brasil pelo Comitê Brasileiro de Registros Ornitológicos

Since 2005, the Brazilian Ornithological Records Committee (CBRO) has published updated checklists of Brazilian birds almost every year. Herein, we present a completely new and annotated version of our checklist. For the first time, we list all bird subspecies known from Brazil that are currently accepted by at least one key ornithological reference work. The inclusion of the subspecies should be seen as a synthesis, and not as a taxonomic endorsement. As such, we include in the new checklist 1919 avian species, 910 of which are treated as polytypic in reference works (2042 subspecies), totaling 3051 taxa at the species and subspecies level. We anticipate that several of the subspecies included in our list may be subject to future taxonomic upgrades to species status, while others will probably be shown to be invalid in the light of future taxonomic studies. The results highlight Brazil as a megadiverse country and reinforce the need for proper enforcement of political tools, laws and international commitments assumed by the country to preserve its biodiversity

Relativistic Binaries in Globular Clusters

Galactic globular clusters are old, dense star systems typically containing 10\super{4}--10\super{7} stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars, globular clusters are the scene of many interesting close dynamical interactions between stars. These dynamical interactions can alter the evolution of individual stars and can produce tight binary systems containing one or two compact objects. In this review, we discuss theoretical models of globular cluster evolution and binary evolution, techniques for simulating this evolution that leads to relativistic binaries, and current and possible future observational evidence for this population. Our discussion of globular cluster evolution will focus on the processes that boost the production of hard binary systems and the subsequent interaction of these binaries that can alter the properties of both bodies and can lead to exotic objects. Direct {\it N}-body integrations and Fokker--Planck simulations of the evolution of globular clusters that incorporate tidal interactions and lead to predictions of relativistic binary populations are also discussed. We discuss the current observational evidence for cataclysmic variables, millisecond pulsars, and low-mass X-ray binaries as well as possible future detection of relativistic binaries with gravitational radiation.Comment: 88 pages, 13 figures. Submitted update of Living Reviews articl

“Escape” of aldosterone production in patients with left ventricular dysfunction treated with an angiotensin converting enzyme inhibitor: Implications for therapy

Despite the findings in randomized trials of a significant effect of angiotensin-converting enzyme (ACE) inhibitors in reducing morbidity and mortality of patients with symptomatic left ventricular dysfunction, the morbidity and mortality of these patients remains relatively high. One potential strategy to further improve morbidity and mortality in these patients is blockade of aldosterone. Many clinicians have assumed that ACE inhibitors would block both angiotensin II and aldosterone. However, there are data to suggest that aldosterone production may “escape” despite the use of an ACE inhibitor. An escape of aldosterone production has several important consequences, including: sodium retention, potassium and magnesium loss, myocardial collagen production, ventricular hypertrophy, myocardial norepinephrine release, endothelial dysfunction, and a decrease in serum high density lipoprotein cholesterol. Due to the potential importance of these mechanisms, the finding that there is a significant correlation between aldosterone production and mortality in patients with heart failure, as well as evidence that an aldosterone antagonist, spironolactone, when administered to patients with heart failure treated with conventional therapy including an ACE inhibitor results in increased diuresis and symptomatic improvement, an international prospective multicenter study has been organized, the Randomized Aldactone Evaluation Study (RALES Pilot Study), to evaluate the safety of blocking the effects of aldosterone in patients with heart failure treated with an ACE inhibitor.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44631/1/10557_2004_Article_BF00877755.pd

Mapping and linking supply- and demand-side measures in climate-smart agriculture. A review

Climate change and food security are two of humanity’s greatest challenges and are highly interlinked. On the one hand, climate change puts pressure on food security. On the other hand, farming significantly contributes to anthropogenic greenhouse gas emissions. This calls for climate-smart agriculture—agriculture that helps to mitigate and adapt to climate change. Climate-smart agriculture measures are diverse and include emission reductions, sink enhancements, and fossil fuel offsets for mitigation. Adaptation measures include technological advancements, adaptive farming practices, and financial management. Here, we review the potentials and trade-offs of climate-smart agricultural measures by producers and consumers. Our two main findings are as follows: (1) The benefits of measures are often site-dependent and differ according to agricultural practices (e.g., fertilizer use), environmental conditions (e.g., carbon sequestration potential), or the production and consumption of specific products (e.g., rice and meat). (2) Climate-smart agricultural measures on the supply side are likely to be insufficient or ineffective if not accompanied by changes in consumer behavior, as climate-smart agriculture will affect the supply of agricultural commodities and require changes on the demand side in response. Such linkages between demand and supply require simultaneous policy and market incentives. It, therefore, requires interdisciplinary cooperation to meet the twin challenge of climate change and food security. The link to consumer behavior is often neglected in research but regarded as an essential component of climate-smart agriculture. We argue for not solely focusing research and implementation on one-sided measures but designing good, site-specific combinations of both demand- and supply-side measures to use the potential of agriculture more effectively to mitigate and adapt to climate change