Amphibian species composition and priorities for regional conservation at the Espinhaço mosaic, Southeastern Brazil

The southern portion of the Espinhaço Range in Brazil is recognized worldwide as a priority area for biodiversity conservation, and it contains a high number of endemic anuran species. We conducted field surveys and compiled published data on amphibian community composition from seven sites within Espinhaço Mosaic (EM; 910,000 ha) to explore the contribution of this area to amphibian species richness in the southern Espinhaço Range. We aimed to describe local and regional community composition and to identify priorities for future amphibian surveys and inventories in the study area. We consider the EM a species-rich area sheltering 73 anuran species, which represents 36.5% of the amphibians known for the state of Minas Gerais, 57.5% of those in the Cerrado biome, and almost 70% of the species in the Espinhaço Range. Unequal sampling effort is a major concern in the study area, and species richness in under-sampled sites might increase as new assessments are conducted. Therefore, sites for which no data are available should be prioritized for species inventories. Although an increase in sampling effort is likely to reduce the proportion of exclusive species (i.e., species known to occur in only one of the seven investigated sites), we conclude that the levels of endemicity indicate a high number of narrowly distributed (micro-endemic) species. We believe anuran community composition and similarities in composition among the sites investigated are influenced by the gradient between the Cerrado and Atlantic Rainforest biomes, which deserves further investigation

Feeding ecology and spraint deposition sites of the Neotropical otter (Lontra longicaudis) at Cavernas do Peruaçu National Park, Brazil

Knowledge on the feeding ecology and habitat use of a species is of essential value for effective conservation. We describe the diet and spraints deposition sites for the Neotropical otter (Lontra longicaudis) at Cavernas do Peruaçu National Park, in south eastern Brazil. We collected spraints and recorded characteristics of the deposition sites from 2007-2010. We described otter diet as the number of faeces in which a given taxon was found and the frequency of occurrence of each taxon. We collected 57 spraints and identified 92 food items from nine different taxa, all from animal origin. Fish was the most frequent taxon, found in 98.3% of our samples, followed by arthropods (22.8%) and mammals (10.5%). We recorded 112 spraint deposition sites, most of them located in caves (80%) and < 10 m from the water (93.4%). In our study area the Neotropical otter relies heavily on fish, and we believe that the behaviour of some fish species makes them more vulnerable to predation. Habitat use by otters has important management implications for the national park, as caves are the main tourist attraction and some tourist tracks are located next to the river. Although a well-implemented management action might seem enough to avoid negative impacts of tourism, we believe that monitoring the Neotropical otter population in our study area is of major conservation concern to evaluate the impacts of this activity

Downscaling the Gap: Protected Areas, Scientific Knowledge and the Conservation of Amphibian Species in Minas Gerais, Southeastern Brazil

Protected areas (PAs) cover a small proportion of the Earth's surface and most species are not covered by the current network. Amphibians are the least represented group in PAs around the world and expanding the network is still the major recommendation for species conservation. We evaluated the effectiveness of PAs in safeguarding endemic amphibians in the Cerrado biome of Minas Gerais state, southeastern Brazil. We conducted a gap analysis to highlight site-based conservation actions for target species within study site. We extracted occurrence points from the national database and calculated the intersection between the minimum convex polygon and natural vegetation remnants for each species. For each target species, we calculated the percentage of the range covered by PAs and assessed the scientific knowledge based on academic publications between 1950–2015. We recorded 206 amphibians in Minas Gerais, of which 127 occur in the Cerrado. We identified 24 target species and concluded that 80% are insufficiently protected by the current PA network. A quarter of the species have zero coverage and most species have < 30% of their range legally protected. In southwestern Minas Gerais, we recommend habitat restoration and connectivity to provide additional habitat to target species. In western Minas Gerais, the creation of PA seems to be the best solution. The distribution of target species is concentrated in the Espinhaço Mountain Range, where we recommend the establishment of biodiversity corridors. We examined 246 publications, most of which focus on taxonomy. Few species have sufficient information to have their conservation status re-assessed, with only 26.8% of publications containing specific information on conservation. Scientific knowledge must be improved for all research areas, especially species distributions and ecology, to support evidence-based conservation and management actions

Molecular basis for the regulation of human glycogen synthase by phosphorylation and glucose-6-phosphate

\ua9 2022, The Author(s). Glycogen synthase (GYS1) is the central enzyme in muscle glycogen biosynthesis. GYS1 activity is inhibited by phosphorylation of its amino (N) and carboxyl (C) termini, which is relieved by allosteric activation of glucose-6-phosphate (Glc6P). We present cryo-EM structures at 3.0–4.0 \uc5 resolution of phosphorylated human GYS1, in complex with a minimal interacting region of glycogenin, in the inhibited, activated and catalytically competent states. Phosphorylations of specific terminal residues are sensed by different arginine clusters, locking the GYS1 tetramer in an inhibited state via intersubunit interactions. The Glc6P activator promotes conformational change by disrupting these interactions and increases the flexibility of GYS1, such that it is poised to adopt a catalytically competent state when the sugar donor UDP-glucose (UDP-glc) binds. We also identify an inhibited-like conformation that has not transitioned into the activated state, in which the locking interaction of phosphorylation with the arginine cluster impedes subsequent conformational changes due to Glc6P binding. Our results address longstanding questions regarding the mechanism of human GYS1 regulation

Gold nanoparticles functionalised with fast water exchanging Gd3+ chelates: linker effects on the relaxivity.

This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1039/C4DT03210AThe relaxivity displayed by Gd(3+) chelates immobilized onto gold nanoparticles is the result of the complex interplay between the nanoparticle size, the water exchange rate and the chelate structure. In this work we study the effect of the length of ω-thioalkyl linkers, anchoring fast water exchanging Gd(3+) chelates onto gold nanoparticles, on the relaxivity of the immobilized chelates. Gold nanoparticles functionalized with Gd(3+) chelates of mercaptoundecanoyl and lipoyl amide conjugates of the DO3A-N-(α-amino)propionate chelator were prepared and studied as potential CA for MRI. High relaxivities per chelate, of the order of magnitude 28-38 mM(-1) s(-1) (30 MHz, 25 °C), were attained thanks to simultaneous optimization of the rotational correlation time and of the water exchange rate. Fast local rotational motions of the immobilized chelates around connecting linkers (internal flexibility) still limit the attainable relaxivity. The degree of internal flexibility of the immobilized chelates seems not to be correlated with the length of the connecting linkers. Biodistribution and MRI studies in mice suggest that the in vivo behavior of the gold nanoparticles was determined mainly by size. Small nanoparticles (HD = 3.9 nm) undergo fast renal clearance and avoidance of the RES organs while larger nanoparticles (HD = 4.8 nm) undergo predominantly hepatobiliary excretion. High relaxivities, allied to chelate and nanoparticle stability and fast renal clearance in vivo suggest that functionalized gold nanoparticles hold great potential for further investigation as MRI contrast agents. This study contributes to a better understanding of the effect of linker length on the relaxivity of gold nanoparticles functionalized with Gd(3+) complexes. It is a relevant contribution towards "design rules" for nanostructures functionalized with Gd(3+) chelates as Contrast Agents for MRI and multimodal imaging.This work was financially supported by Fundação para a Ciência e a Tecnologia, Portugal: PhD grant SFRH/BD/63994/2009 to Miguel Ferreira and Sabbatical Grant SFRH/BSAB/1328/2013 to José Martins at Bath University, UK; and Rede Nacional de NMR (REDE/1517/RMN/2005) for the acquisition of the Varian VNMRS 600 NMR spectrometer in Coimbra. T.B.R. was supported by a Marie Curie Fellowship (FP/- PEOPLE-2009-IEF 254380) and an EMBO Fellowship (ALTF 1145-2009). Financial support from Ministerio de Ciencia e Innovación, Spain, projects SAF2011-23622 (S.C.) and CTQ2010-20960-C02-02 (P.L.-L.), and Comunidad de Madrid, Spain, project S2010/BMD-2349 (S.C. and P.L.-L), is also acknowledged. B. Mousavi and L. Helm acknowledge financial support by the Swiss National Science Foundation. This work was carried out in the frame of the COST D38 Action “Metal Based Systems for Molecular Imaging” and COST TD1004 Action “Theranostics Imaging and Therapy”

Detection and phylogenetic analysis of Orf virus from sheep in Brazil: a case report

<p>Abstract</p> <p>Background</p> <p><it>Orf virus </it>(ORFV), the prototype of the genus <it>Parapoxvirus </it>(PPV), is the etiological agent of contagious ecthyma, a severe exanthematic dermatitis that afflicts domestic and wild small ruminants. Although South American ORFV outbreaks have occurred and diagnosed there are no South American PPV major membrane glycoprotein B2L gene nucleotide sequences available.</p> <p>Case presentation</p> <p>an outbreak of ovine contagious ecthyma in Midwest Brazil was investigated. The diagnosis was based on clinical examinations and molecular biology techniques. The molecular characterization of the virus was done using PCR amplification, cloning and DNA sequencing of the B2L gene. The phylogenetic analysis demonstrated a high degree of identity with ORFV strains, and the isolate was closest to the ORFV-India 82/04 isolate. Another Brazilian ORFV isolate, NE1, was sequenced for comparative analysis and also showed a high degree of identity with an Asian ORFV strain.</p> <p>Conclusion</p> <p>Distinct ORFV strains are circulating in Brazil. This is the first report on the phylogenetic analysis of an ORFV in South America.</p

Assessing the conservation value of secondary savanna for large mammals in the Brazilian Cerrado

Debate about the conservation value of secondary habitats has tended to focus on tropical forests, increasingly recognizing the role of secondary forests for biodiversity conservation. However, there remains a lack of information about the conservation value of secondary savannas. Here, we conducted a camera trap survey to assess the effect of secondary vegetation on large mammals in a Brazilian Cerrado protected area, using a single-season occupancy framework to investigate the response of individual species (species-level models) and of all species combined (community-level models). In addition, we investigated the cost effectiveness of different sampling designs to monitor globally threatened species in the study area. At the community level, savanna that regenerated from eucalyptus plantation had similar occupancy estimate as old growth areas. At the species level, none of the ten species individually assessed seemed to respond to succession stage, with greater support for the effect of other covariates on occupancy, such as distance from water and vegetation physiognomy. These results demonstrate that secondary vegetation does not appear to negatively impact large mammals in the study area and suggest that, given a favorable context, Cerrado mammals can recolonize and use secondary savannas that regenerated from clearcut. However, our study area should be considered a best-case scenario, as it retained key ecological attributes of high-value secondary habitats. Our simulations showed that a sampling design with 60 camera trap sites surveyed during nine occasions is appropriate to monitor most globally threatened species in the study area, and could be a useful starting point for new monitoring initiatives in other Cerrado areas

Revisiting clinical trials on glycemic control and cardiovascular risk

The most relevant clinical trials, assessing the role of glycemic control in reducing cardiovascular risk, are examined. The UKPDS was the first to address this issue. More recent trials (ACCORD, ADVANCE and VADT) are controversial and evidences did not support that strict glycemic control (reflected by normal glycated hemoglobin) exclusively is sufficient to reduce cardiovascular risk in complicated individuals with long-term type 2 diabetes mellitus. Some possible reasons for controversies are included