316 research outputs found

    ConsĂłrcio couve-coentro em cultivo orgĂąnico e sua influĂȘncia nas populaçÔes de joaninhas.

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    O consĂłrcio de culturas Ă© comumente praticado na produção de hortaliças devido a diversos benefĂ­cios econĂŽmicos. Em alguns casos, podem reduzir infestaçÔes de pragas por favorecer a conservação dos inimigos naturais nos agroecossistemas. Avaliou-se a viabilidade agronĂŽmica do consĂłrcio de couve e coentro, sob manejo orgĂąnico, com base em parĂąmetros fitotĂ©cnicos, alĂ©m de sua influĂȘncia sobre populaçÔes de joaninhas (Coleoptera: Coccinellidae), na comparação com os respectivos cultivos solteiros. O coentro, representando a cultura secundĂĄria, foi utilizado com a finalidade de fornecer recursos para as joaninhas. O estudo foi realizado em ĂĄrea do Sistema Integrado de Produção AgroecolĂłgica em SeropĂ©dica-RJ. O experimento consistiu dos consĂłrcios: 1) couve consorciada com coentro, cujas quatro linhas de plantas foram colhidas na fase vegetativa (consĂłrcio I), e 2) couve consorciada com coentro, cujas plantas das duas linhas internas (prĂłximas Ă  linha da couve) foram colhidas na fase vegetativa e as duas linhas externas foram cortadas apĂłs floração (consĂłrcio II). Em ambos consĂłrcios foram avaliados os parĂąmetros fitotĂ©cnicos da couve e do coentro na fase vegetativa (padrĂŁo comercial), enquanto que no consĂłrcio II, tambĂ©m se avaliou as populaçÔes de joaninhas, por meio de coletas semanais de adultos, em comparação com a couve em cultivo solteiro. O delineamento experimental foi em blocos ao acaso com quatro repetiçÔes. O coentro nĂŁo interferiu na produtividade da couve consorciada e sua introdução contribuiu positivamente para a abundĂąncia e diversidade de espĂ©cies de joaninhas. O Ă­ndice de equivalĂȘncia de ĂĄrea para o consĂłrcio I, com referĂȘncia aos rendimentos de biomassa aĂ©rea fresca, foi superior em 92% em relação ao cultivo solteiro. Este resultado demonstra a viabilidade do consĂłrcio I, no manejo orgĂąnico adotado, para plantios de outono nas condiçÔes edafoclimĂĄticas da Baixada Fluminense

    Molecular characterization of beta-tubulin from Phakopsora pachyrhizi, the causal agent of Asian soybean rust

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    ÎČ-tubulins are structural components of microtubules and the targets of benzimidazole fungicides used to control many diseases of agricultural importance. Intron polymorphisms in the intron-rich genes of these proteins have been used in phylogeographic investigations of phytopathogenic fungi. In this work, we sequenced 2764 nucleotides of the ÎČ-tubulin gene (Pp tubB) in samples of Phakopsora pachyrhizi collected from seven soybean fields in Brazil. Pp tubB contained an open reading frame of 1341 nucleotides, including nine exons and eight introns. Exon length varied from 14 to 880 nucleotides, whereas intron length varied from 76 to 102 nucleotides. The presence of only four polymorphic sites limited the usefulness of Pp tubB for phylogeographic studies in P. pachyrhizi. The gene structures of Pp tubB and orthologous ÎČ-tubulin genes of Melampsora lini and Uromyces viciae-fabae were highly conserved. The amino acid substitutions in ÎČ-tubulin proteins associated with the onset of benzimidazole resistance in model organisms, especially at His 6 , Glu 198 and Phe 200 , were absent from the predicted sequence of the P. pachyrhizi ÎČ-tubulin protein

    DETC Induces Leishmania Parasite Killing in Human In Vitro and Murine In Vivo Models: A Promising Therapeutic Alternative in Leishmaniasis

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    Background: Chemotherapy remains the primary tool for treatment and control of human leishmaniasis. However, currently available drugs present serious problems regarding side-effects, variable efficacy, and cost. Affordable and less toxic drugs are urgently needed for leishmaniasis. Methodology/Principal Findings: We demonstrate, by microscopy and viability assays, that superoxide dismutase inhibitor diethyldithiocarbamate (DETC) dose-dependently induces parasite killing (p,0.001) and is able to ??????sterilize?????? Leishmania amazonensis infection at 2 mM in human macrophages in vitro. We also show that DETC-induced superoxide production (p,0.001) and parasite destruction (p,0.05) were reverted by the addition of the antioxidant N-acetylcysteine, indicating that DETC-induced killing occurs through oxidative damage. Furthermore, ultrastructural analysis by electron microscopy demonstrates a rapid and highly selective destruction of amastigotes in the phagosome upon DETC treatment, without any apparent damage to the host cell, including its mitochondria. In addition, DETC significantly induced parasite killing in Leishmania promastigotes in axenic culture. In murine macrophages infected with Leishmania braziliensis, DETC significantly induced in vitro superoxide production (p = 0.0049) and parasite killing (p = 0.0043). In vivo treatment with DETC in BALB/C mice infected with Leishmania braziliensis caused a significant decrease in lesion size (p,0.0001), paralleled by a 100-fold decrease (p = 0.0087) in parasite burden. Conclusions/Significance: Due to its strong leishmanicidal effect in human macrophages in vitro, its in vivo effectiveness in a murine model, and its previously demonstrated in vivo safety profile in HIV treatment, DETC treatment might be considered as a valuable therapeutic option in human leishmaniasis, including HIV/Leishmania co-infection

    Social and dental status along the life course and oral health impacts in adolescents: a population-based birth cohort

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    <p>Abstract</p> <p>Background</p> <p>Harmful social conditions in early life might predispose individuals to dental status which in turn may impact on adolescents' quality of life.</p> <p>Aims</p> <p>To estimate the prevalence of oral health impacts among 12 yr-old Brazilian adolescents (<it>n </it>= 359) and its association with life course socioeconomic variables, dental status and dental services utilization in a population-based birth cohort in Southern Brazil.</p> <p>Methods</p> <p>Exploratory variables were collected at birth, at 6 and 12 yr of age. The Oral Impacts on Daily Performances index (OIDP) was collected in adolescence and it was analyzed as a ranked outcome (OIDP from 0 to 9). Unadjusted and adjusted multivariable Poisson regression with robust variance was performed guided by a theoretical determination model.</p> <p>Results</p> <p>The response rate was of 94.4% (<it>n </it>= 339). The prevalence of OIDP = 1 was 30.1% (CI95%25.2;35.0) and OIDP ≄ 2 was 28.0% (CI95%23.2;32.8). The most common daily activity affected was eating (44.8%), follow by cleaning the mouth and smiling (15.6%, and 15.0%, respectively). In the final model mother schooling and mother employment status in early cohort participant's life were associated with OIDP in adolescence. As higher untreated dental caries at age 6 and 12 years, and the presence of dental pain, gingival bleeding and incisal crowing in adolescence as higher the OIDP score. On the other hand, dental fluorosis was associated with low OIDP score.</p> <p>Conclusion</p> <p>Our findings highlight the importance of adolescent's early life social environmental as mother schooling and mother employment status and the early and later dental status on the adolescent's quality of life regardless family income and use of dental services.</p

    Evaluation of Cellular Phenotypes Implicated in Immunopathogenesis and Monitoring Immune Reconstitution Inflammatory Syndrome in HIV/Leprosy Cases

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    BACKGROUND: It is now evident that HAART-associated immunological improvement often leads to a variety of new clinical manifestations, collectively termed immune reconstitution inflammatory syndrome, or IRIS. This phenomenon has already been described in cases of HIV coinfection with Mycobacterium leprae, most of them belonging to the tuberculoid spectrum of leprosy disease, as observed in leprosy reversal reaction (RR). However, the events related to the pathogenesis of this association need to be clarified. This study investigated the immunological profile of HIV/leprosy patients, with special attention to the cellular activation status, to better understand the mechanisms related to IRIS/RR immunopathogenesis, identifying any potential biomarkers for IRIS/RR intercurrence. METHODS/PRINCIPAL FINDINGS: Eighty-five individuals were assessed in this study: HIV/leprosy and HIV-monoinfected patients, grouped according to HIV-viral load levels, leprosy patients without HIV coinfection, and healthy controls. Phenotypes were evaluated by flow cytometry for T cell subsets and immune differentiation/activation markers. As expected, absolute counts of the CD4+ and CD8+ T cells from the HIV-infected individuals changed in relation to those of the leprosy patients and controls. However, there were no significant differences among the groups, whether in the expression of cellular differentiation phenotypes or cellular activation, as reflected by the expression of CD38 and HLA-DR. Six HIV/leprosy patients identified as IRIS/RR were analyzed during IRIS/RR episodes and after prednisone treatment. These patients presented high cellular activation levels regarding the expression of CD38 in CD8+ cells T during IRIS/RR (median: 77,15%), dropping significantly (p<0,05) during post-IRIS/RR moments (median: 29,7%). Furthermore, an increase of cellular activation seems to occur prior to IRIS/RR. CONCLUSION/SIGNIFICANCE: These data suggest CD38 expression in CD8+ T cells interesting tool identifying HIV/leprosy individuals at risk for IRIS/RR. So, a comparative investigation to leprosy patients at RR should be conducted
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