84 research outputs found

    Improve protective efficacy of a TB DNA-HSP65 vaccine by BCG priming

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    Vaccines are considered by many to be one of the most successful medical interventions against infectious diseases. But many significant obstacles remain, such as optimizing DNA vaccines for use in humans or large animals. The amount of doses, route and easiness of administration are also important points to consider in the design of new DNA vaccines. Heterologous prime-boost regimens probably represent the best hope for an improved DNA vaccine strategy. In this study, we have shown that heterologous prime-boost vaccination against tuberculosis (TB) using intranasal BCG priming/DNA-HSP65 boosting (BCGin/DNA) provided significantly greater protection than that afforded by a single subcutaneous or intranasal dose of BCG. In addition, BCGin/DNA immunization was also more efficient in controlling bacterial loads than were the other prime-boost schedules evaluated or three doses of DNA-HSP65 as a naked DNA. The single dose of DNA-HSP65 booster enhanced the immunogenicity of a single subcutaneous BCG vaccination, as evidenced by the significantly higher serum levels of anti-Hsp65 IgG2a Th1-induced antibodies, as well as by the significantly greater production of IFN-γ by antigen-specific spleen cells. The BCG prime/DNA-HSP65 booster was also associated with better preservation of lung parenchyma

    AVALIAÇÃO DO TEOR DE ANTOCIANINAS EM JABUTICABAS AO LONGO DE SEU DESENVOLVIMENTO FISIOLÓGICO

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    Introdução e objetivos: A jabuticaba é um fruto tropical que apresenta alto valor sensorial e nutricional, cujos frutos apresentam coloração escura devido à presença de antocianinas. A antocianina é uma classe de pigmentos com cores que variam entre azul e vermelho. Em frutos verdes o teor de antocianinas é baixo, pois sua síntese ou desmascaramento ocorre durante o amadurecimento. Desta forma objetivou-se avaliar o teor de antocianinas em jabuticabas ao longo do seu desenvolvimento fisiológico. Metodologia: Os frutos foram coletados na Fazenda e Vinícola Jabuticabal a 35,6Km de Goiânia- GO. A colheita dos frutos iniciou-se aos 14 dias após a antese (DAA) e prorrogou-se até o completo amadurecimento dos frutos, com intervalos de quatro dias entre as coletas. O período compreendido entre a antese (abertura da flor) e o amadurecimento foi de 34 dias. O conteúdo total de antocianinas foi estimado, espectrofotometricamente, segundo o método de Lees e Francis (1972)¹ e Barcia et al. (2012)². A leitura foi realizada no comprimento de onda de 535 nm e os resultados expressos em miligramas de cianidina-3-glicosídio por 100 gramas de amostra. Resultados e discussões: Os teores de antocianinas apresentaram elevação até os 30DAA com valores de: 0,984; 1,101; 13,964; 25,649 e 42,191mg de cianidina-3-glicosídio. Posteriormente notou-se redução destes para 27,018mg de cianidina-3-glicosídio. O aumento significativo até os 30DAA confirma a correspondência entre a síntese de antocianinas e a mudança na coloração durante o amadurecimento dos frutos. Já a redução pode ser justificada pelo fato de que, após a completa formação e amadurecimento dos frutos, inicia-se os processos catabólicos. Conclusões: Pode concluir que para o melhor aproveitamento das antocianinas da jabuticaba é indicado que estas sejam colhidas aos 30 dias após antese

    Synergism in the antibacterial action of ternary mixtures involving silver nanoparticles, chitosan and antibiotics

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    The investigations of the antibacterial actions, observed in ternary associations involving silver nanoparticles (AgNPs), chitosan and the antibiotics azithromycin (AZ), levofloxacin (LE) or tetracycline (TE), against Gram-negative and Gram-positive bacterial strains, were performed by in vitro antimicrobial susceptibility testing and checkerboard assays. The pH impact in the culture medium was carefully discarded, but preserving the best conditions for solubilizing chitosan. The synergistic antibacterial effects were observed in the most combinations of AgNPs, chitosan and antibiotic, leading to a reduction from 37 to 97% in the minimum inhibitory concentration of the drugs. The mechanisms for the enhanced antimicrobial effects were proposed based on the investigations of the adsorptions of the drugs on the silver surfaces through surface-enhanced Raman scattering (SERS) spectroscopy.

    Effect of L-glutamine levels in piglets diets challenged with Escherichia coli lipopolysacharides

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    ABSTRACT Objective. To evaluate the effect of different levels of L-glutamine on weaned and immunologically challenged piglets with Escherichia coli lipopolysaccharides (LPS) on performance parameters, serum cortisol and defense cells. Materials and methods. Four levels of L –glutamine were evaluated (0, 1.0, 1.5, 2.0%) as well as the addition, or no addition, of LPS (0.3μg). 96 piglets were used (48 castrated males and 48 females) of Agroceres x PenArlan lineage, with an initial age of 21 days and 6.06±0.852 kg live weight. An experimental design was used on randomized blocks in a factorial setting 4 x 2 (levels of L- glutamine with or without challenge). Results. Cubic effect was shown for daily weight gain of unchallenged animals, and was better with the addition of 0.41% L- glutamine. Feed conversion improved with increased levels of L -glutamine for challenged animals. In the evaluation of defense cells, there was interaction of leukocytes with the levels of L- glutamine and the immune challenge. Eosinophils and lymphocytes showed a quadratic effect for the levels of L –glutamine, with a maximum value of 1.30% and 0.5%, respectively. Conclusions. L -glutamine supplementation of up to 2% in the diet improves feed conversion and favors the immune serum of weaned piglets challenged with LPS of E. coli

    Understanding Brazil’s catastrophic fires : causes, consequences and policy needed to prevent future tragedies

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    Brazil has experienced unprecedented wildfires in the last decade. Images ofimmense burnt areas or dead animals that failed to escape the 2020 wildfires have shocked the world. To prevent or minimize further similardisasters wemustunderstandthe factors thathave ledto these catastrophic events. The causes and consequences of wildfires entail complex interactions between the biophysical and sociocultural spheres, and suitable management decisions require a sound scientific base. We present the recent panorama of increasing fire outbreaks in the Brazilian biomes, and discuss the causes that have contributed to such fires, their impacts on the environment and overall consequences for human well-being, based on reviewing the extensive specialist literature, on authors’ expert knowledge and information provided by environmental managers, researchers and politicians during a workshop organized to debate the wildfire issue in Brazil. Our up-to-date review is aimed at the academic public, environmental managers and decision- and policy-makers. First, we present evidence on the contrasting effects of fire on different ecosystems. Second, we outline the historic perceptions and policies related to fire use and management in Brazil since its colonization to the present date. Third, we propose means to advance fire prevention and develop successful management strategies. Finally, we answer frequently asked questions to clarify and/or demystify some fire-related issues not always properly addressed in the media

    HPV infection and p53 and p16 expression in esophageal cancer: are they prognostic factors?

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    Background: Esophageal squamous cell carcinoma (ESCC) is a highly lethal malignant tumor. Currently, Human papillomavirus (HPV) is suggested as a potential risk factor for esophageal cancer (EC) in addition to the classic risk factors, alcohol and tobacco, but this hypothesis still remains contradictory. We sought to investigate wether HPV and well-known biomarkers (p16 and p53) and patient-related factors that may have impact on survival of ESCC. Methods: We conducted a prospective cohort study. By using multiplex PCR, we determined the prevalence of high risk HPV in ESCC, and evaluated the immunohistochemical expression of p16 and p53, molecular markers related to esophageal carcinogenesis in order to verify the potential influence of these variables in patients's survival. Survival rates were estimated using Kaplan-Meier methods. A multivariate confirmatory model was performed using Cox proportional hazards regression. Results: Twelve (13.8%) of 87 patients were HPV-DNA positive. Positive reactions of p16 and p53 were 10.7% and 68.6%, respectively. Kaplan-Meier analysis indicated that men (p = 0.025) had poor specific-cancer survival and a shorter progression-free survival (p = 0.050) as compared to women; III or IV clinical stage (p < 0.019) had poor specific-cancer survival and a shorter progression-free survival (p < 0.001) compared to I and II clinical stage; not submitted to surgery (< 0.001) and not submitted to chemoradiotherapy (p = 0.039) had a poor specific-cancer survival, as well. The multivariate analysis showed that HPV, p16 and p53 status are not predictive parameters of progression-free and specific-cancer survival. Conclusion: HPV infection and p53 and p16 expression are not prognostic factors in ESCC.CNPq Universal for providing supplies to the largest study, of which this study is a part of, entitled “The role of human papillomavirus (HPV) as the etiologic agent of esophageal cancer. A cross-sectional study, case-control and longitudinal at Barretos Cancer Hospital”; (Grant number 482666/2012–9 to ALF); INCT HPV [Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) [Grant number 08/57889–1 to LLV]; Conselho Nacional de Desenvolvimento Científico e Tencnológico (CNPq) (Grant number 573799/ 2008–3 to LLV)].info:eu-repo/semantics/publishedVersio
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