Biomassa de Arthrospira platensis: Uma abordagem para produção de bioetanol

Um estudo com a biomassa de Arthrospira platensis foi realizado para otimizar a fermentação com Escherichia coli MS04 obtida por engenharia metabólica. A sacarificação enzimática foi utilizada para liberar a quantidade máxima de glicose. Estes hidrolisados foram fermentados com bactérias etanologênicas, atingindo 5,5 % de etanol, o que corresponde a 52 % de conversão do teor de açúcares no hidrolisado e com mais massa de biomassa a conversão em etanol foi a mesma. O rendimento encontrado neste estudo mostrou que há potencial para a produção de bioetanol a partir de A. platensis e com fermentação com a E. coli MSO4, mas as condições experimentais podem ser melhoradas

Why is leptospirosis hard to avoid for the impoverished? Deconstructing leptospirosis transmission risk and the drivers of knowledge, attitudes, and practices in a disadvantaged community in Salvador, Brazil

Several studies have identified socioeconomic and environmental risk factors for infectious disease, but the relationship between these and knowledge, attitudes, and practices (KAP), and more importantly their web of effects on individual infection risk, have not previously been evaluated. We conducted a cross-sectional KAP survey in an urban disadvantaged community in Salvador, Brazil, leveraging on simultaneously collected fine-scale environmental and epidemiological data on leptospirosis transmission. Residents’ knowledge influenced their attitudes which influenced their practices. However, different KAP variables were driven by different socioeconomic and environmental factors; and while improved KAP variables reduced risk, there were additional effects of socioeconomic and environmental factors on risk. For example, males and those of lower socioeconomic status were at greater risk, but once we controlled for KAP, male gender and lower socioeconomic status themselves were not direct drivers of seropositivity. Employment was linked to better knowledge and a less contaminated environment, and hence lower risk, but being employed was independently associated with a higher, not lower risk of leptospirosis transmission, suggesting travel to work as a high risk activity. Our results show how such complex webs of influence can be disentangled. They indicate that public health messaging and interventions should take into account this complexity and prioritize factors that limit exposure and support appropriate prevention practices

Estudo da hidrólise enzimática de biomassa de microalga empregando uma sequência de enzimas

O emprego de microalgas para desenvolvimento de produtos está em pleno desenvolvimento considerando a composição de diversas espécies e a adaptação das mesmas ao meio de cultivo. Neste trabalho realizou-se o estudo da hidrólise enzimática da biomassa da microalga considerando a potencialidade de produção a partir de cepas de Chlorella sp., Scenedesmus sp., e Spirulina (Arthrospira platensis) empregando uma sequência de enzimas composta de duas amilases e dois complexos de celulases. Para tanto, foi realizado inicialmente a caracterização das espécies, seguindo-se o estudo com a Spirulina, que apresentou 40,02 % de carboidratos e mais que a metade do teor em amido (24,95 %) se mostrando promissor o seu uso para a otimização da hidrólise enzimática. Os melhores resultados de conversão foram encontrados com 12 FPU da enzima CTec2 enquanto que foi com 6,9 FPU da enzima HTec2, alcançando próximo a 100 % de rendimento. Desta forma pode-se concluir que a hidrólise empregando uma sequência de enzimas, alfa-amilase, glucoamilase e celulases mostrou-se eficiente para a microalga Spirulina, mostrando a viabilidade de aplicação da biomassa para o desenvolvimento de outros produtos, tornando a produção de matéria prima para etanol mais renovável

Multidrug-Resistant Nontuberculous Mycobacteria Isolated from Cystic Fibrosis Patients

Worldwide, nontuberculous mycobacteria (NTM) have become emergent pathogens of pulmonary infections in cystic fibrosis (CF) patients, with an estimated prevalence ranging from 5 to 20%. This work investigated the presence of NTM in sputum samples of 129 CF patients (2 to 18 years old) submitted to longitudinal clinical supervision at a regional reference center in Rio de Janeiro, Brazil. From June 2009 to March 2012, 36 NTM isolates recovered from 10 (7.75%) out of 129 children were obtained. Molecular identification of NTM was performed by using PCR restriction analysis targeting the hsp65 gene (PRA-hsp65) and sequencing of the rpoB gene, and susceptibility tests were performed that followed Clinical and Laboratory Standards Institute recommendations. for evaluating the genotypic diversity, pulsed-field gel electrophoresis (PFGE) and/or enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) was performed. the species identified were Mycobacterium abscessus subsp. bolletii (n = 24), M. abscessus subsp. abscessus (n = 6), Mycobacterium fortuitum (n = 3), Mycobacterium marseillense (n = 2), and Mycobacterium timonense (n = 1). Most of the isolates presented resistance to five or more of the antimicrobials tested. Typing profiles were mainly patient specific. the PFGE profiles indicated the presence of two clonal groups for M. abscessus subsp. abscessus and five clonal groups for M. abscesssus subsp. bolletii, with just one clone detected in two patients. Given the observed multidrug resistance patterns and the possibility of transmission between patients, we suggest the implementation of continuous and routine investigation of NTM infection or colonization in CF patients, including countries with a high burden of tuberculosis disease.Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)PDTIS-FIOCRUZUniv Fed Rio de Janeiro, Programa Posgrad Clin Med, Hosp Univ Clementino Fraga Filho, Rio de Janeiro, BrazilUniv Fed Rio Grande do Sul, Programa Posgrad Ciencias Med, Porto Alegre, RS, BrazilUniv Fed Rio de Janeiro, Fac Ciencias Med, Dept Microbiol Imunol & Parasitol, Rio de Janeiro, BrazilInst Fernandes Figueira Fiocruz, Rio de Janeiro, BrazilUniv Estado Rio de Janeiro, Hosp Univ Pedro Ernesto, Rio de Janeiro, BrazilUniv Fed Rio de Janeiro, Inst Microbiol, BR-21941 Rio de Janeiro, BrazilFundacao Oswaldo Cruz, Inst Pesquisa Evandro Chagas, Rio de Janeiro, BrazilInst Doencas Torax, Rio de Janeiro, BrazilJohns Hopkins Univ, Baltimore, MD USAUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilUniv Fed Fluminense, Inst Biomed, Niteroi, RJ, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilFAPERJ: 103.225/2011FAPERJ: 103.287/2011FAPERJ: 110.272/2010FAPERJ: 110.761/2010FAPERJ: 111.497/2008CNPq: 476536/2012-0CNPq: 473444/2010-0CNPq: 567037/2008-8Web of Scienc

Chronic pancreatits in goats: first report in South America

This study reports the clinical and laboratory profile of an adult Saanen goat with chronic pancreatitis admitted in the Cattle and Small Ruminant Practice. The main complaint was loss of weight in the absence of dysphagia and anorexia. Physical examination showed normal vital function, cachexia, body condition score equal (ECC) to 2 (1 to 5), and polyphagia. Parasitological examination of feces and radial immunodiffusion for caprine arthritis encephalitis presented negative results. Laboratory exams showed fasting hyperglycemia, glucosuria, ketonuria and aciduria. Serum amylase activity was 10.5U/L, lower than the values obtained from two healthy animals kept in the CBPR (21.2U/L and 52.2U/L), once reference values for amylase in goats are not available. Insulin assessment, however, was not carried out because there are no laboratories in Brazil that work with goat insulin. After two episodes of bronchopneumonia, the animal was euthanized and necropsied. Hystopathological examination of the pancreas showed serious chronic-active pancreatitis, with marked acinar fibrosis and atrophy associated to rarefaction of islets of Langerhans. Besides, there were ductal hyperplasia with irregularities, and mucoid metaplasia. Thus, clinical, laboratorial and histopathological findings indicate that the animal presented primary chronic pancreatitis, compromising the endocrine and exocrine pancreas.Trabalho apresentado ao 9º Congresso Brasileiro de Buiatria, Goiânia, 2011

A polêmica da vacina e as fake news: : relato de projeto interdisciplinar em prática de residência pedagógica no contexto de ensino remoto emergencial

O seguinte relato de prática pedagógica trata de um projeto interdisciplinar entre os componentes de língua portuguesa, literatura e biologia, realizado com duas turmas de segundo ano do ensino médio em uma escola pública de Porto Alegre, intitulado: “A polêmica da vacina: entre verdades e mentiras”. A aplicação ocorreu com a participação de bolsistas do projeto de “Residência pedagógica” da Universidade Federal do Rio Grande do Sul (UFRGS). Para o planejamento deste projeto, teve-se como base a Aprendizagem Baseada em Projetos (ABP), que, de acordo com Bender (2014), propõe que se trabalhe a partir de problemas reais, com materiais e discussões que possibilitem o desenvolvimento e engajamento dos alunos ao longo do processo de aprendizagem. O projeto foi realizado na modalidade de Ensino Remoto Emergencial (ERE) e ancora-se em perspectivas teóricas que partem de uma abordagem linguística, a qual contribui para as relações dos sujeitos falantes, considerando o contexto social e histórico onde estão inseridos

Population dynamics of synanthropic rodents after a chemical and infrastructural intervention in an urban low-income community.

Synanthropic rodents are ubiquitous in low-income communities and pose risks for human health, as they are generally resistant to control programs. However, few or no studies have evaluated the long-term effect of chemical and infrastructural interventions on rodent population dynamics, especially in urban low-income communities, or evaluated the potential recovery of their population following interventions. We conducted a longitudinal study in a low-income community in the city of Salvador (BA, Brazil) to characterize the effect of interventions (chemical and infrastructural) on the dynamics of rodent population, and documented the post-intervention recovery of their population. We evaluated the degree of rodent infestation in 117 households/sampling points over three years (2014-2017), using tracking plates, a proxy for rodent abundance/activity. We reported a significant lower rodent activity/abundance after the chemical and infrastructural interventions (Z = -4.691 (p < 0.001)), with track plate positivity decreasing to 28% from 70% after and before interventions respectively. Therefore, the combination of chemical and infrastructural interventions significantly decreased the degree of rodent infestation in the study area. In addition, no rodent population rebound was recorded until almost a year post-intervention, and the post-intervention infestation level did not attain the pre-intervention level all through the study. Moreover, among pre-treatment conditions, access to sewer rather than the availability of food was the variable most closely associated with household rodent infestation. Our study indicates that Integrated Pest Management (IPM)-approaches are more effective in reducing rodent infestation than the use of a single method. Our findings will be useful in providing guidance for long-term rodent control programs, especially in urban low-income communities

Molecular architecture of the antiophidic protein DM64 and its binding specificity to myotoxin II from Bothrops aasper venom

Open access article. Creative Commons Attribution 4.0 International License (CC BY 4.0) appliesDM64 is a toxin-neutralizing serum glycoprotein isolated from Didelphis aurita, an ophiophagous marsupial naturally resistant to snake envenomation. This 64 kDa antitoxin targets myotoxic phospholipases A2, which account for most local tissue damage of viperid snakebites. We investigated the noncovalent complex formed between native DM64 and myotoxin II, a myotoxic phospholipase-like protein from Bothrops asper venom. Analytical ultracentrifugation (AUC) and size exclusion chromatography indicated that DM64 is monomeric in solution and binds equimolar amounts of the toxin. Attempts to crystallize native DM64 for X-ray diffraction were unsuccessful. Obtaining recombinant protein to pursue structural studies was also challenging. Classical molecular modeling techniques were impaired by the lack of templates with more than 25% sequence identity with DM64. An integrative structural biology approach was then applied to generate a three-dimensional model of the inhibitor bound to myotoxin II. I-TASSER individually modeled the five immunoglobulin-like domains of DM64. Distance constraints generated by cross-linking mass spectrometry of the complex guided the docking of DM64 domains to the crystal structure of myotoxin II, using Rosetta. AUC, small-angle X-ray scattering (SAXS), molecular modeling, and molecular dynamics simulations indicated that the DM64-myotoxin II complex is structured, shows flexibility, and has an anisotropic shape. Inter-protein cross-links and limited hydrolysis analyses shed light on the inhibitor’s regions involved with toxin interaction, revealing the critical participation of the first, third, and fifth domains of DM64. Our data showed that the fifth domain of DM64 binds to myotoxin II amino-terminal and beta-wing regions. The third domain of the inhibitor acts in a complementary way to the fifth domain. Their binding to these toxin regions presumably precludes dimerization, thus interfering with toxicity, which is related to the quaternary structure of the toxin. The first domain of DM64 interacts with the functional site of the toxin putatively associated with membrane anchorage. We propose that both mechanisms concur to inhibit myotoxin II toxicity by DM64 binding. The present topological characterization of this toxin-antitoxin complex constitutes an essential step toward the rational design of novel peptide-based antivenom therapies targeting snake venom myotoxins.Ye

Simplified sewerage to prevent urban leptospirosis transmission: a cluster non-randomised controlled trial protocol in disadvantaged urban communities of Salvador, Brazil.

INTRODUCTION: Leptospirosis is a globally distributed zoonotic and environmentally mediated disease that has emerged as a major health problem in urban slums in developing countries. Its aetiological agent is bacteria of the genus Leptospira, which are mainly spread in the urine of infected rodents, especially in an environment where adequate sanitation facilities are lacking, and it is known that open sewers are key transmission sources of the disease. Therefore, we aim to evaluate the effectiveness of a simplified sewerage intervention in reducing the risk of exposure to contaminated environments and Leptospira infection and to characterise the transmission mechanisms involved. METHODS AND ANALYSIS: This matched quasi-experimental study design using non-randomised intervention and control clusters was designed to assess the effectiveness of an urban simplified sewerage intervention in the low-income communities of Salvador, Brazil. The intervention consists of household-level piped sewerage connections and community engagement and public involvement activities. A cohort of 1400 adult participants will be recruited and grouped into eight clusters consisting of four matched intervention-control pairs with approximately 175 individuals in each cluster in baseline. The primary outcome is the seroincidence of Leptospira infection assessed through five serological measurements: one preintervention (baseline) and four postintervention. As a secondary outcome, we will assess Leptospira load in soil, before and after the intervention. We will also assess Leptospira exposures before and after the intervention, through transmission modelling, accounting for residents' movement, contact with flooding, contaminated soil and water, and rat infestation, to examine whether and how routes of exposure for Leptospira change following the introduction of sanitation. ETHICS AND DISSEMINATION: This study protocol has been reviewed and approved by the ethics boards at the Federal University of Bahia and the Brazilian National Research Ethics Committee. Results will be disseminated through peer-reviewed publications and presentations to implementers, researchers and participating communities. TRIAL REGISTRATION NUMBER: Brazilian Clinical Trials Registry (RBR-8cjjpgm)