5,671 research outputs found

    Efeito da estimulação prévia sobre a migração de neutrófilos protege contra os efeitos letais da Salmonella typhimurium

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    A inoculação intraperitoneal de 3,8 x 10(9) CFU de Salmonella typhimurium viva causou 100% de mortalidade em ratos. Nesses animais, pequeno número de neutrófilos migraram para a cavidade peritoneal. A injeção intraperitoneal de tioglicolato (TG, 90 mg), carragenina (Cg, 500 mi g) ou salmonella morta pelo calor (KS, 1,9 x10(9) CFU) 24 horas antes do desafio com S. typhimurium viva causou maior (p < 0,01) migração de neutrófilos para a cavidade peritoneal após 6 horas e conferiu proteção aos animais contra os efeitos letais da bactéria que foram da ordem de 50%, 83% e 80%, respectivamente. Todavia, o tratamento semelhante dos animais com o meio de cultivo "infusão de cérebro e coração" (brain heart infusion-BHI) estéril exerceu proteção de apenas 23%. O número de neutrófilos que migraram para a cavidade peritoneal representou apenas 10% do verificado nos outros tratamentos. A atividade fagocitária não estava relacionada ao índice de sobrevivência dos animais, uma vez que tal atividade foi duas vezes maior no grupo KS do que nos grupos Tg e Cg, e a taxa de sobrevivência nesse grupo foi semelhante à observada no grupo Cg. Esses resultados sugerem que o aumento da migração de neutrófilos para o sítio infeccioso induzida pelas administrações prévias das diferentes substâncias é um importante fator associado com a proteção dos animais contra os efeitos letais da infecção bacteriana.The intraperitoneal inoculation of 3.8 x 10(9) CFU of alive Salmonella typhimurium caused 100% mortality in rats. In these animals a small number of neutrophils migrated to the peritoneal cavity. The intraperitoneal inoculation of the animals with thioglycollate (Tg, 90 mg), carrageenin (Cg, 500 mu g), or killed S. typhimurium (KS, 1.9 x 10(9) CFU) 24 hours before challenge with alive S. typhimurium caused a significant neutrophil migration to the peritoneal cavity (determined 6 hours after challenge) and protected the animals against the lethal effect of the bacteria at a rate of 50%, 83% and 80%, respectively. However, similar treatment of the animals with brain heart infusion broth (BHI, S. typhimurium grout medium) protected the animals by only 23%. The migrating neutrophils in these animals represented less than 10% of those observed with other treatments. The phagocytosis activity was not associated with the survival rate as this activity was 2 times higher in the KS group than in the Tg and Cg groups, and the survival rate in this group was similar to that observed in Cg. These results suggest that the increase of neutrophil migration to the infectious site is an important factor associated with protection of the animals against the lethal effect of the bacterial infection

    Systematic Review of Hepatitis E Virus in Brazil: A One-Health Approach of the Human-Animal-Environment Triad

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    Brazil is the fifth largest country in the world with diverse socioeconomic and sanitary conditions, also being the fourth largest pig producer in the world. The aim of the present systematic review was to collect and summarize all HEV published data from Brazil (from 1995 to October 2020) performed in humans, animals, and the environment, in a One Health perspective. A total of 2173 papers were retrieved from five search databases (LILACs, Mendeley, PubMed, Scopus, and Web of Science) resulting in 71 eligible papers after application of exclusion/inclusion criteria. Data shows that HEV genotype 3 (HEV-3) was the only retrieved genotype in humans, animals, and environment in Brazil. The South region showed the highest human seroprevalence and also the highest pig density and industry, suggesting a zoonotic link. HEV-1 and 2 were not detected in Brazil, despite the low sanitary conditions of some regions. From the present review we infer that HEV epidemiology in Brazil is similar to that of industrialized countries (only HEV-3, swine reservoirs, no waterborne transmission, no association with low sanitary conditions). Hence, we alert for the implementation of HEV surveillance systems in swine and for the consideration of HEV in the diagnostic routine of acute and chronic hepatitis in humans.This research received no external funding

    Stellar equilibrium configurations of white dwarfs in the f(R,T)f(R,T) gravity

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    In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, na\-mely, f(R,T)f(R,T) gravity, for which RR and TT stand for the Ricci scalar and trace of the energy-momentum tensor, respectively. Considering the functional form f(R,T)=R+2λTf(R,T)=R+2\lambda T, with λ\lambda being a constant, we obtain the hydrostatic equilibrium equation for the theory. Some physical properties of white dwarfs, such as: mass, radius, pressure and energy density, as well as their dependence on the parameter λ\lambda are derived. More massive and larger white dwarfs are found for negative values of λ\lambda when it decreases. The equilibrium configurations predict a maximum mass limit for white dwarfs slightly above the Chandrasekhar limit, with larger radii and lower central densities when compared to standard gravity outcomes. The most important effect of f(R,T)f(R,T) theory for massive white dwarfs is the increase of the radius in comparison with GR and also f(R)f(R) results. By comparing our results with some observational data of massive white dwarfs we also find a lower limit for λ\lambda, namely, λ>−3×10−4\lambda >- 3\times 10^{-4}.Comment: To be published in EPJ

    Mechanics of Cosserat Generalized Continuum and Modelling in Structural Geology

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    The conception and interpretation of models in structural geology, specially the numerical ones, are eminently based on the principles of classic continuum mechanics, where the intrinsic formulation has high degree of symmetry in its very essence. However, the geological structures carry in all scales a remarkable level of asymmetry. On the other hand, the mechanics of Cosserat generalized continuum, by incorporating characteristic lengths of the matter structure in its constitutive and strength laws, leads by itself to the asymmetry and the heterogeneity of the kinematic and dynamic fields responsible for rock fabric. Based on the intrinsic formulation of the Cosserat continuum, the present work emphasizes conceptual, analytical and numerical models that suggest the expansion in the interpretation of the genesis and development of geological structures, in particular those found in fault zones

    A religião na reconstrução de uma teoria crítica social em Max Horkheimer

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    This paper is an effort to focus some aspects about a Philosophy of Religion inside Critic Theory, specially in the thought of Max Horkheimer.Este artigo procura enfocar algumas questões concernentes a uma Filosofia da Religião no interior da Teoria Crítica, mais precisamente no pensamento de Max Horkheimer

    Soil Management Of Sugarcane Fields Affecting Co2 Fluxes

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The harvesting system of green sugarcane, characterized by mechanized harvesting and no crop burning, affects soil quality by increasing the remaining straw left on the soil surface after harvesting, thus, contributing to the improvement of physical, chemical, and microbiological soil attributes, influencing CO2 fluxes. This study aimed to evaluate CO2 fluxes and their relation to soil properties in sugarcane crops under different harvesting managements: burned (B), Green harvesting for 5 years (G-5) and Green harvesting for ten years (G-10). For this, a 1 ha sampling grid with 30 points was installed in each area, all located in the Northeast of Sao Paulo State, Brazil. In each point, CO2 fluxes were measured and the soil was sampled to analyze the microbial biomass, physical (soil moisture and temperature, mean weight diameter, bulk density, clay, macroporosity and microporosity) and chemical characterization (pH, organic C, base saturation and P). The CO2 fluxes were divided into four quantitative criteria: high, moderate, low and very low from the Statistical Division (mean, first quartile, median and third quartile) and the other data were classified according this criterion. The Principal Component Analysis (PCA) was used to identify the main soil attributes that influence CO2 fluxes. The results showed that G-10 CO2 fluxes were 28 and 41 % higher than those in the G-5 and B treatments, respectively. The PCA analysis showed that macroporosity was the main soil attribute that influenced the high CO2 fluxes.736543551Sao Paulo State Foundation for Research Support [FAPESP - 2010/18.979-5, 2011/04.842-0]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Spatial And Temporal Variability Of Soil Co2 Flux In Sugarcane Green Harvest Systems

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The sugarcane green harvest system, characterized by mechanized harvesting and the absence of crop burning, affects soil quality by increasing crop residue on the soil surface after harvest; thus, it contributes to improving the physical, chemical, and microbiological properties and influences the soil carbon content and CO2 flux (FCO2). This study aimed to evaluate the spatial and temporal variability of soil FCO2 in sugarcane green harvest systems. The experiment was conducted in two areas of sugarcane in Sao Paulo, Brazil: the first had a 5-year history of sugarcane green harvest (SG-5) and the second had a longer history of 10 years (SG-10). The temporal FCO2 were evaluated in the dry and rainy periods, and spatial variability in the dry period, and related to soil chemical and physical properties, including organic C porosity, bulk density, soil penetration resistance, mean weight diameter of soil aggregates, clay, P, S, Ca, Mg and Fe. The temporal variability indicated no differences between the dry and rainy periods in SG-10, while in SG-5 soil moisture was increased by 33 % in the rainy period. The spatial variability indicated a different pattern from the temporal one, where FCO2 in SG-10 was correlated with soil temperature, air-filled pore space, total porosity, soil moisture, and the Ca and Mg contents; in the SG-5 area, FCO2 was correlated with soil mean weight diameter of soil aggregates and the sulfur content.40FAPESP/SPFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
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