Concentrations of metals in liver of Guiana dolphins (Sotalia guianensis) from an estuary in Southeast of Brazil

Concentrations of Fe, Zn, Cu, Mn, Pb, Cr, Co and Ni were measured in the liver of 21 Guiana dolphins from the Estuarine-Lagoon Complex of Iguape-Cananéia, in order to indicate the impact of their habitat and to verify if these concentrations differ between the sexes and age classes. The concentrations followed the order: Fe>Zn>Cu>Mn>Pb>Cr>Co>Ni, and with the exception of lead, all concentrations were in the same order of magnitude observed for the species. The accumulations between the sexes were similar, while copper were higher in infants, suggesting that the organ can act as a reservoir for Co in a period of rapidly postnatal growth. Lead mean concentration (3.17 μg g-1) were the highest described for the species, which from a toxicological point of view may be a matter of concern. This accumulation suggests a trophic transfer, indicating the contamination of the food chain, which possibly reflects the local environmental contamination caused by ancient lead mining

Branched-chain amino acids promote endothelial dysfunction through increased reactive oxygen species generation and inflammation

Branched‐chain amino acids (BCAA: leucine, isoleucine and valine) are essential amino acids implicated in glucose metabolism and maintenance of correct brain function. Elevated BCAA levels can promote an inflammatory response in peripheral blood mononuclear cells. However, there are no studies analysing the direct effects of BCAA on endothelial cells (ECs) and its possible modulation of vascular function. In vitro and ex vivo studies were performed in human ECs and aorta from male C57BL/6J mice, respectively. In ECs, BCAA (6 mmol/L) increased eNOS expression, reactive oxygen species production by mitochondria and NADPH oxidases, peroxynitrite formation and nitrotyrosine expression. Moreover, BCAA induced pro‐inflammatory responses through the transcription factor NF‐κB that resulted in the release of intracellular adhesion molecule‐1 and E‐selectin conferring endothelial activation and adhesion capacity to inflammatory cells. Pharmacological inhibition of mTORC1 intracellular signalling pathway decreased BCAA-induced pro‐oxidant and pro‐inflammatory effects in ECs. In isolated murine aorta, BCAA elicited vasoconstrictor responses, particularly in pre‐contracted vessels and after NO synthase blockade, and triggered endothelial dysfunction, effects that were inhibited by different antioxidants, further demonstrating the potential of BCAA to induce oxidative stress with functional impact. In summary, we demonstrate that elevated BCAA levels generate inflammation and oxidative stress in ECs, thereby facilitating inflammatory cells adhesion and endothelial dysfunction. This might contribute to the increased cardiovascular risk observed in patients with elevated BCAA blood levels.This study was supported by Ministerio de Economía y Competitividad (MINECO SAF2016‐80305‐P), Instituto de Salud Carlos III (ISCIII) Fondo Europeo de Desarrollo Regional (FEDER) a way to build Europe (PI14/00386, PI14/0041, PIE13/00051, PI13/01488; PI17‐01495, CiberCV, CiberDEM), FP7 grant e‐PREDICE, by the Fundación Renal Iñigo Álvarez de Toledo (FRIAT)/Instituto Reina Sofía de Investigación Nefrológica and from Roche‐IdiPa

In vitro Assessment of Thermal Changes in Human Teeth during Photodynamic Antimicrobial Chemotherapy Performed with Red Light Sources

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Photo-disinfection of deep dentin caries lesions may be a useful tool for preserving tooth structure. However, increase of pulpal temperature higher than 5.5 degrees C may put pulp vitality in danger. Objectives: This in vitro study evaluated thermal effects of radiation of the red spectrum (lambda = 600-700 nm, 94 J cm(-2)) on pulpal and periodontal areas when irradiating deep dentin cavities in human teeth. Methods: Tooth preparation was performed at occlusal surface in 10 human teeth, which were irradiated by five different light units, four diode GaAlAs lasers: Coherent (C); Kondortech (B); Whitening lase (W); and K5000 with 2 different tips (K1 and K2), as well as one light emitting diode Laserbeam (LED). After application of toluidine blue O dye in the cavity, variation of temperature was measured in duplicate using a digital thermometer and 2 K-type thermocouples one placed inside the pulpal chamber and the other on root surface at the cementoenamel junction, simultaneously. The mean average temperature rise (Delta T) was calculated for each group. Results: Delta T values were analyzed by ANOVA and Tukey tests. Pulpal temperature increase ranged from 0.62 +/- 0.51 to 1.25 +/- 0.50 degrees C. Group C presented the highest Delta T, which was statistically significant different from B, K1, and K2. The lowest Delta T value was found for group K2, which statistically differed from the group W. No other statistically significant difference was found. At the root surface, Delta T values were lower than 0.5 degrees C for all devices and no statistically significantly difference was found among them. Conclusion: With regard to thermal side effects, the use of these red light sources operating at 94 J cm(-2) may be considered harmless for dental tissues.20614751480Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [620160/2006-3

Structural insights into ring-building motif domains involved in bacterial sporulation.

Components of specialized secretion systems, which span the inner and outer membranes in Gram-negative bacteria, include ring-forming proteins whose oligomerization was proposed to be promoted by domains called RBM for "Ring-Building Motifs". During spore formation in Gram-positive bacteria, a transport system called the SpoIIIA-SpoIIQ complex also assembles in the double membrane that surrounds the forespore following its endocytosis by the mother cell. The presence of RBM domains in some of the SpoIIIA proteins led to the hypothesis that they would assemble into rings connecting the two membranes and form a conduit between the mother cell and forespore. Among them, SpoIIIAG forms homo-oligomeric rings in vitro but the oligomerization of other RBM-containing SpoIIIA proteins, including SpoIIIAH, remains to be demonstrated. In this work, we identified RBM domains in the YhcN/YlaJ family of proteins that are not related to the SpoIIIA-SpoIIQ complex. We solved the crystal structure of YhcN from Bacillus subtilis, which confirmed the presence of a RBM fold, flanked by additional secondary structures. As the protein did not show any oligomerization ability in vitro, we investigated the structural determinants of ring formation in SpoIIIAG, SpoIIIAH and YhcN. We showed that in vitro, the conserved core of RBM domains alone is not sufficient for oligomerization while the β-barrel forming region in SpoIIIAG forms rings on its own. This work suggests that some RBMs might indeed participate in the assembly of homomeric rings but others might have evolved toward other functions

Compósito cimentício com elevado teor de fibra de coco tratada: propriedades físicas e durabilidade

O aproveitamento da fibra de coco na construção civil pode diminuir o consumo de agregados minerais comoareia e brita, e melhorar propriedades físicas e mecânicas de um compósito cimentício. No entanto, um dospontos mais precários está relacionado à degradação acelerada da fibra vegetal pela ação química da matrizcimentícia. Então, avaliou-se a incorporação da fibra de coco com um novo tratamento, e sua influência naspropriedades físicas e durabilidade do compósito cimentício. O tratamento utilizou látex natural, sílica ativa efibra de coco na proporção de 10%, em relação à massa de cimento, para a produção de corpos de prova. Foramdeterminadas as capacidades de atenuação térmica e acústica, massa específica e executados ensaiosmecânicos e de durabilidade. Os dados experimentais indicaram melhora do desempenho termoacústico donovo compósito em até 20% por comparação com o desempenho do compósito cimentício sem a sua presença.Os resultados preliminares obtidos permitem concluir que o compósito pode ser aproveitado na construçãocivil para produção de tijolos de alvenaria para vedação.Palavras-chave: Materiais alternativos de construção, Fibras vegetais, Durabilidade, Sustentabilidade