Heterologous expression and functional characterization of a GH10 endoxylanase from \u3ci\u3eAspergillus fumigatus\u3c/i\u3e var. \u3ci\u3eniveus\u3c/i\u3e with potential biotechnological application

Xylanases decrease the xylan content in pretreated biomass releasing it from hemicellulose, thus improving the accessibility of cellulose for cellulases. In this work, an endo-β-1,4-xylanase from Aspergillus fumigatus var. niveus (AFUMN-GH10) was successfully expressed. The structural analysis and biochemical characterization showed this AFUMN-GH10 does not contain a carbohydrate-binding module. The enzyme retained its activity in a pH range from 4.5 to 7.0, with an optimal temperature at 60°C. AFUMN-GH10 showed the highest activity in beechwood xylan. The mode of action of AFUMNGH10 was investigated by hydrolysis of APTS-labeled xylohexaose, which resulted in xylotriose and xylobiose as the main products. AFUMN-GH10 released 27% of residual xylan from hydrothermally-pretreated corn stover and 14% of residual xylan from hydrothermally-pretreated sugarcane bagasse. The results showed that environmentally friendly pretreatment followed by enzymatic hydrolysis with AFUMN-GH10 in low concentration is a suitable method to remove part of residual and recalcitrant hemicellulose from biomass

BALB/c and C57BL/6 Mice Cytokine Responses to Trypanosoma cruzi Infection Are Independent of Parasite Strain Infectivity

Trypanosoma cruzi is the etiologic agent of Chagas' disease, which affects 6-7 million people worldwide. Different strains of T. cruzi present specific genotypic and phenotypic characteristics that affect the host-pathogen interactions, and thus, the parasite has been classified into six groups (TcI to TcVI). T. cruzi infection presents two clinical phases, acute and chronic, both with distinct characteristics and important participation by the immune system. However, the specific contributions of parasite and host factors in the disease phases are not yet fully understood. The murine model for Chagas' disease is well-established and reproduces important features of the human infection, providing an experimental basis for the study of host lineages and parasite strains. Thus, we evaluated acute and chronic infection by the G (TcI) and CL (TcVI) strains of T. cruzi, which have distinct tropisms and infectivity, in two inbred mice lineages (C57BL/6 and BALB/c) that display variable degrees of susceptibility to different T. cruzi strains. Analysis of the parasite loads in host tissues by qPCR showed that CL strain established an infection faster than the G strainat the same time, the response in BALB/c mice, although diverse in terms of cytokine secretion, was initiated earlier than that in C57BL/6 mice. At the parasitemia peak in the acute phase, we observed, either by confocal microscopy or by qPCR, that the infection was disseminated in all groups analyzed, with some differences concerning parasite tropismat this point, all animals responded to infection by increasing the serum concentrations of cytokines. However, BALB/c mice seemed to better regulate the immune response than C57BL/6 mice. Indeed, in the chronic phase, C57BL/6 mice still presented exacerbated cytokine and chemokine responses. In summary, our results indicate that in these experimental models, the deregulation of immune response that is typical of chronic Chagas' disease may be due to control loss over pro-and anti-inflammatory cytokines early in the acute phase of the disease, depending primarily on the host background rather than the parasite strain.FAPESPCAPESCNPqUniv Fed Sao Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Bioquim, Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Bioquim, Sao Paulo, BrazilFAPESP: 2011/51475-3FAPESP: 2014/21338-2CNPq: 302068/2016-3Web of Scienc

HISTÓRIA DE VIDA DE ESPÉCIES DA FAMÍLIA ARIIDAE E AUCHENIPTERIDAE (PISCES: SILURIFORMES) NA PENÍNSULA BRAGANTINA, LITORAL AMAZÔNICO

Siluriformes habit regions of mud bottoms, estuaries and rivers. Ariidae and Auchenipteridae, are very frequent in the fisheries carried out and landed in the Northeast of Pará. Thus, this work had as objective to study the different forms of use of the specimens considering bioecological aspects. The samplings were done monthly from September 2012 to September 2013in the Furo Grande and Furo do Taici. Nets were used and the degree of exposure to the sea was considered for the definition of the collection sites (Furo Grande - outermost and Furo Taici - innermost). Cathorops spixii and Sciades herzbergii, were the most captured species. Pseudauchenipterus nodosus, is more tolerant to some salinity content. It was noticed that the Furo do Taici, is a place used for feeding and growth by some species. Cathorops agassizii was the one that had the lowest catch volume probably because it occupies the same niche as C. spixii, a frequent species that closes its entire cycle due to the estuary.Keywords: catfish feeding; reproduction; estuary.Bagres da ordem Siluriformes habitam regiões de fundos lamosos de estuários e rios. Ariidae e Auchenipteridae são bem frequentes nas pescarias realizadas e desembarcadas no Nordeste do Pará. Assim, este trabalho teve como objetivo estudar as diferentes formas de uso dos espécimes dessas famílias considerando aspectos bioecológicos. As amostragens foram realizadas mensalmente de setembro de 2012 a setembro de 2013, no Furo Grande e no Furo do Taici. Redes de tapagens foram utilizadas e foi considerado o grau de exposição ao mar para a definição dos locais de coleta (Furo Grande – mais externo e Furo do Taici – mais interno). Cathorops spixii e Sciades herzbergii foram as espécies mais capturadas. Pseudauchenipterus nodosus se mostra um pouco mais tolerante a salinidade. Percebeu-se que o Furo do Taici, é um local utilizado para alimentação e crescimento por algumas espécies. Cathorops agassizii foi a que obteve o menor volume de captura provavelmente por ocupar o mesmo nicho de C. spixii, espécie é frequente e que fecha todo o seu ciclo de vida dentro do estuário.Palavras-chave: Bagres, alimentação, reprodução, estuário

Protocolo de Incubação e Criação Artificial de Tucano-toco (Ramphastos toco) utilizado no Parque das Aves, Foz do Iguaçu, PR

Este texto descreve um protocolo de incubação e alimentação de filhotes de Ramphastos toco, realizado no Parque das Aves, um zoológico focado na conservação de aves da mata atlântica. Foram coletados de três ovos da mesma espécie, efetuado incubação artificial, criação manual dos filhotes que nasceram e transferência dos indivíduos para um recinto após se tornarem independentes. O processo de incubação envolveu o uso de uma incubadora INCA 100 a uma temperatura de 37,5°C com umidade controlada entre 55% e 60%. Os ovos foram examinados a cada dois dias usando um ovoscópio para monitorar o desenvolvimento embrionário, a frequência cardíaca e o peso. Apenas dois dos três ovos coletados estavam embrionados e estes eclodiram com sucesso. O sucesso na criação destes ramphastídeos deu subsídios para elaboração de um protocolo que pudesse aumentar a taxa de sucesso na reprodução do Tucano-Toco e preparar a equipe para o cuidado de filhotes dessa espécie em outras possíveis eventualidades

Heterologous expression and functional characterization of a GH10 endoxylanase from \u3ci\u3eAspergillus fumigatus\u3c/i\u3e var. \u3ci\u3eniveus\u3c/i\u3e with potential biotechnological application

Xylanases decrease the xylan content in pretreated biomass releasing it from hemicellulose, thus improving the accessibility of cellulose for cellulases. In this work, an endo-β-1,4-xylanase from Aspergillus fumigatus var. niveus (AFUMN-GH10) was successfully expressed. The structural analysis and biochemical characterization showed this AFUMN-GH10 does not contain a carbohydrate-binding module. The enzyme retained its activity in a pH range from 4.5 to 7.0, with an optimal temperature at 60°C. AFUMN-GH10 showed the highest activity in beechwood xylan. The mode of action of AFUMNGH10 was investigated by hydrolysis of APTS-labeled xylohexaose, which resulted in xylotriose and xylobiose as the main products. AFUMN-GH10 released 27% of residual xylan from hydrothermally-pretreated corn stover and 14% of residual xylan from hydrothermally-pretreated sugarcane bagasse. The results showed that environmentally friendly pretreatment followed by enzymatic hydrolysis with AFUMN-GH10 in low concentration is a suitable method to remove part of residual and recalcitrant hemicellulose from biomass

ENDODONTIA REGENERATIVA: ALTERAÇÃO DE PARADIGMA NO TRATAMENTO DE DENTES NECROSADOS

Durante o desenvolvimento da dentição o traumatismo dentário pode resultar em necrose pulpar e levar a uma perda prematura dos dentes permanentes. Dentes com ápices imaturos apresentam desafios na limpeza e modelagem dos canais, na obturação e possibilidade de fraturas radiculares devido a paredes finas ou enfraquecidas da raiz.. Comumente a apicificação é realizada com trocas da pasta de hidróxido de cálcio ou a criação de uma barreira apical com agregado trióxido mineral (MTA). Apesar de ser a terapia mais empregada, essa apenas promove o fechamento apical, não estimulando o término do desenvolvimento radicular o que acarretará na persistência de um dente enfraquecido e com um prognóstico desfavorável. A revascularização pulpar pode ser considerada atualmente como uma alternativa terapêutica à apicificação e é indicado para casos de necrose pulpar em dentes jovens. Neste estudo observou-se que a revascularização pulpar trata-se de um tratamento promissor que possibilita tanto o fechamento apical quanto o término do desenvolvimento radicular. A técnica consiste na desinfecção do sistema de canais radiculares, seguido de estímulos de sangramento da região periapical, para formação de coágulo e células indiferenciadas no interior do canal, induzindo a reparação tecidual. Portanto, a endodontia regenerativa apresenta vantagens, porém como é um tratamento relativamente novo, pouco se sabe sobre seus efeitos em longo prazo devendo ser submetida a maiores estudos laboratoriais e clínicos, afim de que as dúvidas existentes sejam esclarecidas e o tratamento seja aprimorado visando o melhor prognóstico para os pacientes

Donor Simvastatin Treatment Is Safe and Might Improve Outcomes After Liver Transplantation: A Randomized Clinical Trial.

BACKGROUND The current curative approaches for ischemia/reperfusion injury on liver transplantation are still under debate for their safety and efficacy in patients with end-stage liver disease. We present the SIMVA statin donor treatment before Liver Transplants study. METHODS SIMVA statin donor treatment before Liver Transplants is a monocentric, double-blind, randomized, prospective tial aiming to compare the safety and efficacy of preoperative brain-dead donors' treatment with the intragastric administration of 80 mg of simvastatin on liver transplant recipient outcomes in a real-life setting. Primary aim was incidence of patient and graft survival at 90 and 180 d post-transplant; secondary end-points were severe complications. RESULTS The trial enrolled 58 adult patients (18-65 y old). The minimum follow-up was 6 mo. No patient or graft was lost at 90 or 180 d in the experimental group (n = 28), whereas patient/graft survival were 93.1% (P = 0.016) and 89.66% (P = 0.080) at 90 d and 86.21% (P = 0.041) and 86.2% (P = 0.041) at 180 d in the control group (n = 29). The percentage of patients with severe complications (Clavien-Dindo ≥IIIb) was higher in the control group, 55.2% versus 25.0% in the experimental group (P = 0.0307). The only significant difference in liver tests was a significantly higher gamma-glutamyl transferase and alkaline phosphatase at 15 d (P = 0.017), (P = 0.015) in the simvastatin group. CONCLUSIONS Donor simvastatin treatment is safe, and may significantly improve early graft and patient survival after liver transplantation, although further research is mandatory

Association between PaO2/FiO2 ratio and thrombotic events in COVID-19 patients

PaO2/FiO(2) (P/F ratio) is considered a marker of hypoxia/hypoxemia and mortality. Several prothrombotic changes are associated with the decrease of P/F ratio. The role of P/F ratio in patients with arterial and venous thrombosis remains unclear. The aim of this study was to assess in patients with coronavirus disease 2019 (COVID-19), the association between P/F ratio and arterial/venous thrombosis. One thousand and four hundred and six COVID-19 patients were recruited; 289 (21%) patients had P/F ratio < 200 and 1117 (79%) >= 200. Compared to the patients with P/F ratio >= 200, those with P/F ratio < 200 were older and with higher levels of glycemia, D-dimer and lower levels of albumin. Multiple linear regression analysis showed that albumin (standardized coefficient beta: 0.156; SE: 0.001; p = 0.0001) and D-dimer (standardized coefficient beta: -0.135; SE: 0.0001; p = 0.0001) were associated with P/F ratio. During the hospitalization 159 patients were transferred in intensive care unit (ICU), 253 patients died, 156 patients had arterial or venous thrombotic events. A bivariate logistic analysis was performed to analyze the predictors of thrombosis in COVID-19 patients; P/F ratio < 200 (Odds Ratio: [OR] 1.718, 95% Confidence Interval [CI] 1.085-2.718, p = 0.021), albumin (OR 1.693, 95% CI 1.055-2.716, p = 0.029), D-dimer (OR 3.469, 95% CI 2.110-5.703, p < 0.0001), coronary artery disease (CAD) (OR 1.800, 95% CI 1.086-2.984, p = 0.023) and heart failure (OR 2.410 95% CI 1.385-4.193, p = 0.002) independently predicted thrombotic events in this population. This study suggests that the P/F ratio is associated with thrombotic events by promoting a hypercoagulation state in patients hospitalized for COVID-19