Classificação numérica da qualidade de um Latossolo Amarelo sob sistema de integração lavoura-pecuária

Ações antrópicas afetam a atmosfera da terra, despertando para uma consciência global sobre a necessidade de sistemas agrícolas sustentáveis. O objetivo deste estudo foi determinar índices de sustentabilidade do solo para um sistema de integração lavoura-pecuária em um Latossolo Amarelo do cerrado brasileiro no Piauí, utilizando uma classificação numérica. Foram estudados três sistemas de manejo do solo: preparo convencional (PC) com disco de arado e grade pesada em cultivo de soja; plantio direto com rotação de milho soja e milheto como cobertura viva (NT + M); e dois sistemas de integração lavoura-pecuária, um com cinco meses, em pastagens e cultivo de soja (ICL + S) e outro com pastejo contínuo (ICL + P). Uma área sob mata nativa (NF) foi avaliado, como um solo sob condições naturais. Propriedades físicas, químicas e biológicas foram avaliadas no 0,00-0,05 m camada. Na análise de componentes principais, os ambientes ICL + S e ICL + P foram classificados como um único grupo, e pode ser caracterizados pelas propriedades de carbono orgânico no solo, reservatórios de carbono e nitrogênio no solo, o nitrogênio da biomassa microbiana, e total de nitrogênio. A propriedade do solo que melhor caracterizou o ambiente CT foi a atividade da enzima FDA (hidrolisa acetato). As propriedades que melhor caracterizam o ambiente NF são a capacidade de troca catiônica, carbono da biomassa microbiana, microporosidade, índice de estabilidade de agregados, diâmetro médio geométrico e percentagem de agregados estáveis> 2,00 milímetros.Anthropic action is affecting the Earth's atmosphere, awakening a global awareness about the need for sustainable farming systems. The objective of this study was to determine indices of soil sustainability for an integrated crop-livestock system in a Yellow Latosol of the Brazilian Cerrado in Piauí by using a numerical rating. Three systems of soil management were studied: an area under conventional tillage (CT) with plow disk and heavy harrow and soybean cultivation; an area under no-tillage with soybean-maize rotation and millet as a cover crop (NT+M); and two areas under an Integrated Crop-Livestock System, one with five-month pasture grazing and soybean cultivation and the other with continuous pasture grazing (ICL + S and ICL + P, respectively). An area under Native Forest (NF) was evaluated as well as a soil under natural conditions. The physical, chemical, and biological properties were evaluated in the 0.00-0.05 m layer. The environments ICL + S and ICL + P were classified as a single group, and can be characterized by the properties soil organic carbon, soil carbon and nitrogen pools, microbial biomass nitrogen, and total soil N. The property that best characterizes the CT environment is enzyme activity FDA (Fluorescein diacetate hydrolysis). The properties that best characterize the NF environment are cation exchange capacity, microbial biomass carbon, microporosity, aggregate stability index, geometric mean diameter, and percentage of stable >2.00 mm aggregates.Facultad de Ciencias Agrarias y Forestale

Activation of Human CD11b+ B1 B-Cells by Trypanosoma cruzi-Derived Proteins Is Associated With Protective Immune Response in Human Chagas Disease

B-cells mediate humoral adaptive immune response via the production of antibodies and cytokines, and by inducing T-cell activation. These functions can be attributed to distinct B-cell subpopulations. Infection with Trypanosoma cruzi, the causative agent of Chagas disease, induces a polyclonal B-cell activation and lytic antibody production, critical for controlling parasitemia. Individuals within the chronic phase of Chagas disease may remain in an asymptomatic form (indeterminate), or develop severe cardiomyopathy (cardiac form) that can lead to death. Currently, there is no effective vaccine to prevent Chagas disease, and no treatment to halt the development of the cardiomyopathy once it is installed. The pathology associated with cardiac Chagas disease is a result of an inflammatory reaction. Thus, discovering characteristics of the host's immune response that favor the maintenance of favorable heart function may unveil important immunotherapeutic targets. Given the importance of B cells in antibody production and parasite control, we investigated T. cruzi-derived antigenic fractions responsible for B-cell activation and whether frequencies and functional characteristics of B-cell subpopulations are associated with different clinical outcomes of human Chagas disease. We stimulated cells from indeterminate (I) and cardiac (C) Chagas patients, as well as non-infected individuals (NI), with T. cruzi-derived protein- (PRO), glycolipid- (GCL) and lipid (LIP)-enriched fractions and determined functional characteristics of B-cell subpopulations. Our results showed that the frequency of B-cells was similar amongst groups. PRO, but not GCL nor LIP, led to an increased frequency of B1 B-cells in I, but not C nor NI. Although stimulation with PRO induced higher TNF expression by B1 B-cells from C and I, as compared to NI, it induced expression of IL-10 in cells from I, but not C. Stimulation with PRO induced an increased frequency of the CD11b+ B1 B-cell subpopulation, which was associated with better cardiac function. Chagas patients displayed increased IgM production, and activation of gamma-delta T-cells, which have been associated with B1 B-cell function. Our data showed that PRO activates CD11b+ B1 B-cells, and that this activation is associated with a beneficial clinical status. These findings may have implications in designing new strategies focusing on B-cell activation to prevent Chagas disease cardiomyopathy

Genomics and epidemiology for gastric adenocarcinomas (GE4GAC): a Brazilian initiative to study gastric cancer

Abstract Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixture found in Brazil, stimulated the implementation of the GE4GAC project. GE4GAC aims to embrace epidemiological, clinical, molecular and microbiological data from Brazilian controls and patients with malignant and pre-malignant gastric disease. In this letter, we summarize the main goals of the project, including subject and sample accrual and current findings

Epicoccum nigrum P16, a Sugarcane Endophyte, Produces Antifungal Compounds and Induces Root Growth

Background: Sugarcane is one of the most important crops in Brazil, mainly because of its use in biofuel production. Recent studies have sought to determine the role of sugarcane endophytic microbial diversity in microorganism-plant interactions, and their biotechnological potential. Epicoccum nigrum is an important sugarcane endophytic fungus that has been associated with the biological control of phytopathogens, and the production of secondary metabolites. In spite of several studies carried out to define the better conditions to use E. nigrum in different crops, little is known about the establishment of an endophytic interaction, and its potential effects on plant physiology. Methodology/Principal Findings: We report an approach based on inoculation followed by re-isolation, molecular monitoring, microscopic analysis, plant growth responses to fungal colonization, and antimicrobial activity tests to study the basic aspects of the E. nigrum endophytic interaction with sugarcane, and the effects of colonization on plant physiology. The results indicate that E. nigrum was capable of increasing the root system biomass and producing compounds that inhibit the in vitro growth of sugarcane pathogens Fusarium verticillioides, Colletotrichum falcatum, Ceratocystis paradoxa, and Xanthomomas albilineans. In addition, E. nigrum preferentially colonizes the sugarcane surface and, occasionally, the endophytic environment. Conclusions/Significance: Our work demonstrates that E. nigrum has great potential for sugarcane crop application because it is capable of increasing the root system biomass and controlling pathogens. The study of the basic aspects of the interaction of E. nigrum with sugarcane demonstrated the facultative endophytism of E. nigrum and its preference for the phylloplane environment, which should be considered in future studies of biocontrol using this species. In addition, this work contributes to the knowledge of the interaction of this ubiquitous endophyte with the host plant, and also to a better use of microbial endophytes in agriculture.State of Sao Paulo Research Foundation (FAPESP)FAPESP (State of Sao Paulo Research Foundation) [02/14143-3, 10/08286-2]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq