Root Decomposition of Elephant Grass Pastures Grazed at Different Management Intensities

Grazing management may alter chemical composition of plant components affecting nutrient cycling. Among pasture management tools, adjustment of stocking rate (SR) and N fertilization have potential to affect nutrient cycling in the grassland ecosystem (Dubeux et al. 2007). Excreta from grazing animal and litter are the two major pathways of nutrient return on grazed pastures (Thomas 1992). Fertilization and SR may alter these pathways by different forms. Increasing fertilization generally increases pasture net primary productivity. Stocking rate affects different pasture and animal responses. Regarding nutrient cycling, increasing SR will likely increase proportion of nutrient returned through excreta as opposed to litter, increasing as a result nutrient losses (Dubeux et al. 2006). Root system may also be affected by management intensity. Frequent defoliation and low plant nutrition level may reduce root biomass (Richards 1993) and affect its decomposition. This study evaluated the effect of different SR´s and N fertilization levels on the decomposition of elephant grass roots

The Leishmania amazonensis TRF (TTAGGG repeat-binding factor) homologue binds and co-localizes with telomeres

<p>Abstract</p> <p>Background</p> <p>Telomeres are specialized structures at the end of chromosomes essential for maintaining genome stability and cell viability. The importance of telomeric proteins for telomere maintenance has increased our interest in the identification of homologues within the genus <it>Leishmania</it>. The mammalian TRF1 and TRF2 proteins, for example, bind double-stranded telomeres via a Myb-like DNA-binding domain and are involved with telomere length regulation and chromosome end protection. In addition, TRF2 can modulate the activity of several enzymes and influence the conformation of telomeric DNA. In this work, we identified and characterized a <it>Leishmania </it>protein (LaTRF) homologous to both mammalian TRF1 and TRF2.</p> <p>Results</p> <p>LaTRF was cloned using a PCR-based strategy. ClustalW and bl2seq sequence analysis showed that LaTRF shared sequence identity with the <it>Trypanosoma brucei </it>TRF (TbTRF) protein and had the same degree of sequence similarities with the dimerization (TRFH) and the canonical DNA-binding Myb-like domains of both mammalian TRFs. LaTRF was predicted to be an 82.5 kDa protein, indicating that it is double the size of the trypanosome TRF homologues. Western blot and indirect immunofluorescence combined with fluorescence <it>in situ </it>hybridization showed that LaTRF, similarly to hTRF2, is a nuclear protein that also associates with parasite telomeres. Native and full length LaTRF and a mutant bearing the putative Myb-like domain expressed in bacteria bound double-stranded telomeric DNA <it>in vitro</it>. Chromatin immunoprecipitation showed that LaTRF interacted specifically with telomeres <it>in vivo</it>.</p> <p>Conclusion</p> <p>The nuclear localization of LaTRF, its association and co-localization with parasite telomeres and its high identity with TbTRF protein, support the hypothesis that LaTRF is a <it>Leishmania </it>telomeric protein.</p

Inventário de Expectativas de Resultados em Usuários de Crack (IERUC): construção e validação

Objetivos: Desenvolver e validar uma escala que avalie as expectativas de resultados em usuários de crack internados. Método: Estudo transversal, com amostra por conveniência. Inicialmente os itens do IERUC surgiram de frases de usuários divulgadas pela mídia e das falas de usuários de crack internados. Apareceram 41 frases, foram selecionadas 25 e submetidas a um grupo focal de 15 usuários de crack, os quais apontaram 18 frases. Um grupo de sete juízes especialistas em dependência química avaliou os 18 itens e aprovou 17, em cinco fatores teóricos. Resultados: Na validação semântica e psicométrica, o IERUC com 17 itens e cinco fatores foi aplicado em 170 homens internados, usuários de crack e após a análise fatorial a escala resultou 14 itens, distribuídos em quatro fatores, versão final apresentada neste estudo. Conclusões: Os resultados satisfatórios de validade e confiabilidade do IERUC definiram boas propriedades psicométricas, com base em um modelo de quatro fatores que avaliam as expectativas de resultados relacionadas ao uso de crack

Bagaço de cana-de-açúcar como único volumoso para vacas mestiças lactantes em regiões semiáridas

The objective of this work was to evaluate the effects of different levels of sugarcane bagasse, as exclusive roughage, on nutrient intake and digestibility, feeding behavior, microbial protein synthesis, and dairy performance of crossbred cows. Ten lactating Girolando breed cows (600±34.3 kg body weight) were assigned to a replicated 5×5 Latin square design. The control diet, based on spineless cactus, sugarcane bagasse, and concentrate, was formulated to meet the average production of 20 kg of milk per day, with 3.5% fat. The evaluated levels of sugarcane bagasse were: 30, 38, 46, and 54% dry matter bases. The intake and digestibility of dry matter decreased linearly with sugarcane bagasse levels. Rumination time was higher in cows fed 54% sugarcane bagasse. The inclusion levels had no effect on non-esterified fatty acid contents or on the efficiency of microbial protein synthesis, but beta-hydroxybutyrate concentrations showed a quadratic pattern to the bagasse levels. Higher yields of 3.5% fat-corrected milk were obtained with cows fed 30% sugarcane bagasse. Sugarcane bagasse inclusion in the diet of crossbred dairy cows decreases their performance; however, the bagasse can be used as exclusive roughage when associated with 70% concentrate.O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de bagaço de cana-de-açúcar, como volumoso exclusivo, sobre consumo e digestibilidade de nutrientes, comportamento ingestivo, síntese de proteína microbiana e desempenho leiteiro de vacas mestiças. Dez vacas da raça Girolando (600±34,3 kg de peso corporal) foram distribuídas em delineamento de quadrado latino duplo 5×5. A dieta controle, baseada em palma forrageira, bagaço de cana-de-açúcar e concentrado, foi formulada para atender a média de produção de 20 kg de leite por dia, com 3,5% de gordura. Foram avaliados os seguintes níveis de bagaço de cana-de-açúcar: 30, 38, 46 e 54% da matéria seca. O consumo e a digestibilidade de matéria seca diminuíram linearmente com os níveis de bagaço. O tempo de ruminação foi maior para vacas alimentadas com 54% de bagaço. Os níveis de inclusão não tiveram efeito sobre o conteúdo de ácidos graxos não esterificados ou sobre a síntese de proteína microbiana, mas as concentrações de β-hidroxibutirato apresentaram comportamento quadrático com os níveis de bagaço. Maiores produções de leite corrigido a 3,5% de gordura foram obtidas com vacas alimentadas com 30% de bagaço. A inclusão do bagaço de cana-de-açúcar na dieta de vacas mestiças reduz seu desempenho; contudo, o bagaço pode ser utilizado como volumoso exclusivo quando associado a 70% de concentrado

Spatial Evaluation and Modeling of Dengue Seroprevalence and Vector Density in Rio de Janeiro, Brazil

Dengue is a major public health problem in many tropical regions of the world, including Brazil, where Aedes aegypti is the main vector. We present a household study that combines data on dengue fever seroprevalence, recent dengue infection, and vector density, in three neighborhoods of Rio de Janeiro, Brazil, during its most devastating dengue epidemic to date. This integrated entomological–serological survey showed evidence of silent transmission even during a severe epidemic. Also, past exposure to dengue virus was highly associated with age and living in areas of high movement of individuals and social/commercial activity. No association was observed between household infestation index and risk of dengue infection in these areas. Our findings are discussed in the light of current theories regarding transmission thresholds and relative role of mosquitoes and humans as vectors of dengue viruses

Descrição dos casos hospitalizados pela COVID-19 em profissionais de saúde nas primeiras nove semanas da pandemia, Brasil, 2020

Objective. Describing the COVID-19 hospitalization in health professionals in Brazil. Methods. Serial cases descriptive study; we included the cases with illness between February 21st and April 15th, 2020; registered in Flu Surveillance Information System (SIVEP-Gripe, in Brazilian acronym). Results. From the 184 (1.76%) cases, 110 (59.8%) were female, with a median age of 44 years (min-max: 23-85). Of the 184, 89 (48.4%) are nursing professionals and 50 (27.2%) are doctors. Still, 92 (50.0%) presented comorbidity, with heart disease predominating (n = 37; 40.2%). Of the 112 professionals with a record of evolution, 85 (75.9%) were cured and 27 (24.1%) died, 18 (66.7%) of whom were male. Conclusion. The profile descripted is similar to the population’s in age and comorbidities, but different in relation to sex. The most affected areas were nursing and medicine.Objetivo. Descrever os casos hospitalizados pela COVID-19 em profissionais de saúde no Brasil. Métodos. Estudo descritivo de tipo Série de Casos; foram incluídos aqueles com adoecimento entre 21 de fevereiro e 15 de abril de 2020, registrados no Sistema de Informação de Vigilância da Gripe (SIVEP-Gripe). Resultados. Dos 184 casos, 110 (59,8%) eram do sexo feminino, com mediana de idade de 44 anos (mínima-máxima: 23-85), 89 (48,4%) eram profissionais da enfermagem e 50 (27,2%) médicos. Ainda, 92 (50,0%) apresentavam comorbidade, predominando cardiopatias (n=37; 40,2%). Dos 112 profissionais com registro de evolução, 85 (75,9%) alcançaram cura e 27 (24,1%) foram a óbito, 18 destes do sexo masculino. Conclusão. O perfil dos profissionais de saúde hospitalizados por COVID-19 é semelhante ao da população quanto à idade e comorbidades; porém, diferente quanto ao sexo. As áreas profissionais mais acometidas foram a Enfermagem e a Medicina