Resistência de genótipos de feijão-caupi Vigna unguiculata a Bemisia tabaci Biótipo B (Hemiptera: Aleyrodidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Virulência de Thyrinteina arnobia virus (TaV) e de Bacillus thuringiensis à Thyrinteina arnobia (Lepidoptera: Geometridae): efeito da temperatura no desenvolvimento das lagartas e do pH da calda de pulverização

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Marcadores sorológicos da hepatite B em usuários de um Centro de Testagem para o HIV

Esta investigação objetivou estudar a prevalência de marcadores sorológicos de infecção pelo vírus da hepatite B e analisar possíveis fatores de risco em 404 usuários submetidos à sorologia anti-HIV no Centro de Testagem e Aconselhamento de Ribeirão Preto, SP, Brasil. A prevalência global dos marcadores para o vírus da hepatite B foi de 14,6%, idêntica à encontrada para o anti-HBc, com valores de 1% para o HBsAg e anti-HBc IgM. Após ajuste por regressão logística, os marcadores de infecção do vírus B mostraram associação com as variáveis: idade, local de residência, uso de drogas endovenosas e positividade para o HIV. A prevalência de infecção pelo vírus da imunodeficiência humana foi de 6,9%. Marcadores do vírus B foram detectados em 55,6% dos usuários de drogas endovenosas e em 42,9% dos positivos ao vírus da imunodeficiência humana, confirmando altos índices de infecção nestes grupos específicos.

Prevalência dos marcadores sorológicos dos vírus das hepatites B e D na área indígena Apyterewa, do grupo Parakanã, Pará, Brasil

Com o objetivo de estudar a prevalência dos vírus das hepatites B (HBV) e D (HDV), nas aldeias Apyterewa e Xingu, do grupo Parakanã, e avaliar o impacto da vacinação contra a hepatite B, iniciada nessas aldeias em 1995, foram coletadas, em 2004, 258 amostras de soro para análise dos marcadores sorológicos das hepatites B e D, por técnicas imunoenzimáticas; cujos resultados revelaram padrão de endemicidade moderada com prevalência total de infecção pelo HBV de 55,7%, com 5,4% de portadores do vírus, na aldeia Apyterewa, e de 49,5%, com 1,1% de portadores, na Xingu; 31,4% de anti-HBs+ como marcador isolado nas duas aldeias, e não foi detectada sorologia positiva para o HDV entre portadores do HBV. Caracterizamos, em base laboratorial, a presença de portadores crônicos do HBV, ausência de portadores do HDV e emergência de perfil vacinal entre os susceptíveis, confirmando a efetividade e a necessidade de manter a vacinação, principalmente no primeiro ano de vida, e, ainda, a necessidade de desenvolver vigilância epidemiológica efetiva para detecção precoce da infecção pelo HDV, entre os portadores do HBV.

Caracterização e ocorrência de bidens mosaic virus (bimv) em regiões produtoras de alface no Estado de São Paulo

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Ocorrência do subtipo B do vírus da imunodeficiência felina em gatos domésticos da região sul do estado do Rio Grande do Sul, Brasil

In Brazil there are few studies on the occurrence of the feline immunodeficiency virus (FIV) infection and its subtypes, which are essential for the development of vaccines and new diagnostic tests. The present study investigated the occurrence of the FIV infection between 2010 and 2011 in domestic cats submitted to medical attendance in the city of Pelotas and nearby area. Total blood samples of seventy cats, suspected (28) or not (42) of infection by FIV were analyzed by nested PCR in order to perform a diagnosis. The results pointed to a FIV infection frequency of 15.7% (11/70) and the analysis of the risk factors related to infection (sex, age and clinical condition) evidenced a greater occurrence in cats up to 10 years of age with chronic and recurrent infections. Eight samples found positive by nested PCR were submitted to DNA sequencing indicating that only the subtype B was detected in the studied region.

Serological investigation of rabies virus neutralizing antibodies in bats captured in the eastern Brazilian Amazon

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Identification of Novel Compounds Inhibiting Chikungunya Virus-Induced Cell Death by High Throughput Screening of a Kinase Inhibitor Library

Chikungunya virus (CHIKV) is a mosquito-borne arthrogenic alphavirus that causes acute febrile illness in humans accompanied by joint pains and in many cases, persistent arthralgia lasting weeks to years. The re-emergence of CHIKV has resulted in numerous outbreaks in the eastern hemisphere, and threatens to expand in the foreseeable future. Unfortunately, no effective treatment is currently available. The present study reports the use of resazurin in a cell-based high-throughput assay, and an image-based high-content assay to identify and characterize inhibitors of CHIKV-infection in vitro. CHIKV is a highly cytopathic virus that rapidly kills infected cells. Thus, cell viability of HuH-7 cells infected with CHIKV in the presence of compounds was determined by measuring metabolic reduction of resazurin to identify inhibitors of CHIKV-associated cell death. A kinase inhibitor library of 4,000 compounds was screened against CHIKV infection of HuH-7 cells using the resazurin reduction assay, and the cell toxicity was also measured in non-infected cells. Seventy-two compounds showing >= 50% inhibition property against CHIKV at 10 mu M were selected as primary hits. Four compounds having a benzofuran core scaffold (CND0335, CND0364, CND0366 and CND0415), one pyrrolopyridine (CND0545) and one thiazol-carboxamide (CND3514) inhibited CHIKV-associated cell death in a dose-dependent manner, with EC50 values between 2.2 mu M and 7.1 mu M. Based on image analysis, these 6 hit compounds did not inhibit CHIKV replication in the host cell. However, CHIKV-infected cells manifested less prominent apoptotic blebs typical of CHIKV cytopathic effect compared with the control infection. Moreover, treatment with these compounds reduced viral titers in the medium of CHIKV-infected cells by up to 100-fold. In conclusion, this cell-based high-throughput screening assay using resazurin, combined with the image-based high content assay approach identified compounds against CHIKV having a novel antiviral activity -inhibition of virus-induced CPE - likely by targeting kinases involved in apoptosis.

Occurrence of Groundnut ringspot virus on Brazilian peanut crops

A high incidence of plants with mosaic, chlorotic spots, ringspots, necrosis, smaller leaves, and stunting was observed on peanut crops (Arachis hypogaea L.) in Itapolis, So Paulo State, Brazil. Transmission electron microscope examination of thin sections of infected leaves revealed the presence of spheroidal particles, ca. 80 nm in diameter, suggestive of Tospovirus. A DNA fragment of similar to 600 bp was amplified by RT-PCR from total RNA extracted from infected tissues using primers specific for the nucleocapsid gene of Groundnut ringspot virus (GRSV). Nucleotide and deduced amino acid sequences of the fragments showed high identities with known GRSV isolates.

Vertical transmission of hepatitis C virus: A tale of multiple outcomes

Globally, hepatitis C virus (HCV) infection affects approximately 130 million people and 3 million new infections occur annually. HCV is also recognized as an important cause of chronic liver disease in children. The absence of proofreading properties of the HCV RNA polymerase leads to a highly error prone replication process, allowing HCV to escape host immune response. The adaptive nature of HCV evolution dictates the outcome of the disease in many ways. Here, we investigated the molecular evolution of HCV in three unrelated children who acquired chronic HCV infection as a result of mother-to-child transmission, two of whom were also coinfected with HIV-1. The persistence of discrete HCV variants and their population structure were assessed using median joining network and Bayesian approaches. While patterns of viral evolution clearly differed between subjects, immune system dysfunction related to HIV coinfection or persistent HCV seronegativity stand as potential mechanisms to explain the lack of molecular evolution observed in these three cases. In contrast, treatment of HCV infection with PegIFN, which did not lead to sustained virologic responses in all 3 cases, was not associated with commensurate variations in the complexity of the variant spectrum. Finally, the differences in the degree of divergence suggest that the mode of transmission of the virus was not the main factor driving viral evolution. (C) 2013 Elsevier B. V. All rights reserved.

Development of a peptide ELISA for the diagnosis of Equine arteritis virus

A peptide-based indirect ELISA was developed to detect antibodies against Equine arteritis virus (EAV). Two peptides for epitope C of protein GP5 and fragment E of protein M were designed, synthesized, purified and used as antigens either alone or combined. Ninety-two serum samples obtained from the 2010 Equine viral arteritis outbreak, analyzed previously by virus neutralization, were evaluated by the ELISA here developed. The best resolution was obtained using peptide GP5. The analysis of the inter- and intraplate variability showed that the assay was robust. The results allow concluding that this peptide-based ELISA is a good alternative to the OIE-prescribed virus neutralization test because it can be standardized between laboratories, can serve as rapid screening, can improve the speed of diagnosis of EAV-negative horses and can be particularly useful for routine surveillance in large populations. (C) 2014 Elsevier B.V. All rights reserved.

Molecular and phylogenetic characterization based on the complete genome of a virulent pathotype of Newcastle disease virus isolated in the 1970s in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)