Asymptomatic Leishmania infection in blood donors from a major blood bank in Northeastern Brazil: a cross-sectional study

This study has estimated the risk of Leishmania transmission via blood transfusion in one of the largest blood banks in Northeastern Brazil, where visceral leishmaniasis is endemic. Five hundred blood samples from donors were tested for circulating Leishmania spp. DNA by real-time PCR. Positive samples were tested by a species-specific conventional PCR targeting Leishmania infantum . Overall, 6.2% (95% CI: 4.1–8.3%) of the samples carried Leishmania DNA and in one sample the species was confirmed as L. infantum . No statistically significant differences were found in relation to gender, sex, education level, incomeas well as the place of residence between positive and negative blood donors. Our results confirm the presence of asymptomatic Leishmania carriers among blood donors in a large blood bank in Northeastern Brazil. Considering the studied population, we estimate that for every 1,000 blood donors screened, 41 to 83 will be positive for Leishmania DNA. This finding reinforces the urgent need for elaborating specific Blood bank guidelines to allow the early detection of asymptomatic Leishmania carriers among blood donors before their blood products are transfused to uninfected individuals

Comparison of indirect ELISA based on recombinant protein NcSRS2 and IFAT for detection of Neospora caninum antibodies in sheep Comparação entre ELISA baseado no antígeno recombinante NcSRS2 e RIFI para detecção de anticorpos de Neospora caninum em ovinos

Neospora caninum, an Apicomplexan parasite that can causes abortion, is responsible for considerable economic and reproductive losses in livestock. The purpose of the present study was to determine whether recombinant NcSRS2 is a suitable indirect ELISA antigen for determining specific immune response to N. caninum in sheep. A total of 441 serum samples were subjected to IFAT and rNcSRS2 based-ELISA, with both tests performing similarly. The sensitivity and specificity of indirect ELISA were 98.6 and 98.3%, respectively. The kappa index shows 0.98 concordance between the two tests, which is considered excellent. Seroprevalences of 30.8 and 32.0% were detected by IFAT and indirect ELISA, respectively, showing these tests did not differ significantly on this measure (p > 0.05). Serological analysis showed that HisG tag was detected by Western Blotting recognizing rNcSRS2 protein. The potential value of rNcSRS2-based ELISA as a highly specific and sensitive tool for serological diagnosis is also supported by the strong agreement found between IFAT and ELISA. The results support the potential use of recombinant protein NcSRS2 as an antigen in indirect ELISA in sheep.<br>Neospora caninum é um parasito Apicomplexa que pode causar abortos e é reconhecido como agente importante responsável por perdas econômicas e reprodutivas. Este estudo avaliou a proteína recombinante NcSRS2 como antígeno para ELISA indireto na determinação de resposta imune para N. caninum em ovinos. 441 amostras de soro foram analisadas por IFAT e ELISA indireto com rNcSRS2 e ambos os testes revelaram comportamento similar. A sensibilidade e especificidade de ELISA indireto foram 98,6 e 98,3%, respectivamente. O índice kappa mostrou uma concordância entre os dois testes com valor de 0,98, que é considerado excelente. Prevalências de 30,8 e 32,0% detectadas por IFAT e ELISA indireto, respectivamente, mostraram que os testes não diferiram significativamente nesse aspecto (P > 0.05). A análise sorológica revelou que os anticorpos específicos da cauda de histidina reconheceu por Western Blotting a proteína recombinante NcSRS2. O valor potencial do ELISA indireto baseado no antígeno rNcSRS2 como ferramenta altamente específica e sensível para diagnóstico sorológico é também reforçado pela alta concordância dos valores obtidos com IFAT e com ELISA indireto. Esses resultados respaldam o uso potencial da proteína rNcSRS2 como antígeno em ELISA indireto em ovinos

PCR sensitivity of peripheral blood of dogs co-infected with Leishmania spp. and Ehrlichia spp. in endemic area of Brazil

Submitted by Ana Beatriz Oliveira ([email protected]) on 2019-03-28T12:48:57Z No. of bitstreams: 1 PCR sensitivity of peripheral blood of dogs co-infected with.pdf: 971329 bytes, checksum: 44d607dac455edd04b0b8162516a6cf5 (MD5)Approved for entry into archive by Ana Beatriz Oliveira ([email protected]) on 2019-03-28T13:09:43Z (GMT) No. of bitstreams: 1 PCR sensitivity of peripheral blood of dogs co-infected with.pdf: 971329 bytes, checksum: 44d607dac455edd04b0b8162516a6cf5 (MD5)Made available in DSpace on 2019-03-28T13:09:43Z (GMT). No. of bitstreams: 1 PCR sensitivity of peripheral blood of dogs co-infected with.pdf: 971329 bytes, checksum: 44d607dac455edd04b0b8162516a6cf5 (MD5) Previous issue date: 2018Universidade Federal da Grande Dourados. Programa de Pós-Graduação em Ciências da Saúde. Dourados, MS, Brasil.Universidade Federal da Grande Dourados. Programa de Pós-Graduação em Ciências da Saúde. Dourados, MS, Brasil.Universidade Federal da Grande Dourados. Graduação de Medicina. Dourados, MS, Brasil.Centro de Controle de Zoonoses de Campo Grande. Campo Grande, MS, Brasil.Centro de Controle de Zoonoses de Campo Grande. Campo Grande, MS, Brasil.Universidade Federal da Grande Dourados. Faculdade de Ciências Exatas e Tecnologia. Dourados, MS, Brasil.Fundação Oswaldo Cruz. Instituto Aggeu Magalhães. Recife, PE, Brasil.Universidade Federal da Grande Dourados. Programa de Pós-Graduação em Ciências da Saúde. Dourados, MS, Brasil / Universidade Federal da Grande Dourados. Faculdade de Ciências da Saúde. Dourados, MS, Brasil.INTRODUCTION: Peripheral blood of 400 dogs infected with Leishmania and Ehrlichia were analyzed using polymerase chain reaction (PCR), and clinical signs were characterized. METHODS: PCR and parasitological tests were conducted. RESULTS: PCR was positive for Leishmania in 84.75%, and parasitological tests showed that 63.25% and 31.75% were positive for Leishmania and Ehrlichia, respectively. All animals showed more than three clinical signs. PCR results were negative for Leishmania in 15.25% of the samples. CONCLUSIONS: Conventional PCR of peripheral blood can be used for diagnosing canine visceral leishmaniasis in combination with other techniques, especially in uncertain cases that need species identification

PCR sensitivity of peripheral blood of dogs co-infected with Leishmania spp. and Ehrlichia spp. in endemic area of Brazil

Abstract INTRODUCTION Peripheral blood of 400 dogs infected with Leishmania and Ehrlichia were analyzed using polymerase chain reaction (PCR), and clinical signs were characterized. METHODS PCR and parasitological tests were conducted. RESULTS PCR was positive for Leishmania in 84.75%, and parasitological tests showed that 63.25% and 31.75% were positive for Leishmania and Ehrlichia, respectively. All animals showed more than three clinical signs. PCR results were negative for Leishmania in 15.25% of the samples. CONCLUSIONS Conventional PCR of peripheral blood can be used for diagnosing canine visceral leishmaniasis in combination with other techniques, especially in uncertain cases that need species identification

The development of an enzyme-linked immunosorbent assay for Trypanosoma vivax antibodies and its use in epidemiological surveys

There are data indicating that the distribution of Trypanosoma vivax in the Brazilian territory is expanding with potential to reach other areas, where the vectors are present. The detection of anti-trypanosomal antibodies in serum provides important information of the trypanosomal status in cattle herds. For this reason, an enzyme-linked immunosorbent assay (Tv-ELISA-Ab) with crude antigen from one Brazilian isolate of T. vivax was developed and evaluated. The sensitivity and specificity were respectively 97.6 and 96.9%. In the evaluation of cross-reactions, three calves inoculated with T. evansi trypimastigotes blood forms showed optical densities (OD) under the cut-off during the whole experimental period, except one at 45 days post-inoculation. With relation to Babesia bovis, B. bigemina, and Anaplasma marginale, which are endemic hemoparasites in the studied area, the cross-reactions were shown to be 5.7, 5.3, and 1.1%, respectively. The first serological survey of Pantanal and state of Pará showed that T. vivax is widespread, although regions within both areas had significantly different prevalences. Therefore, this Tv-ELISA-Ab may be a more appropriate test for epidemiological studies in developing countries because the diagnostic laboratories in most countries may be able to perform an ELISA, which is not true for polymerase chain reaction

Bioenergia: desenvolvimento, pesquisa e inovação

Com 27 trabalhos produzidos por pesquisadores do Instituto de Pesquisa em Bioenergia (Bioen), da Unesp, este livro oferece uma ampla visão sobre as áreas que compõem o segmento. Seu principal objetivo é contribuir para melhorar a compreensão dos vários aspectos da bioenergia, em especial no Brasil, que figura entre os países com maior nível de desenvolvimento tecnológico no setor. Os artigos abordam uma série abrangente de questões relacionadas à bioenergia, como a construção genética das plantas de cana-de-açúcar visando ao aumento de produtividade, a disseminação de sementes para estimular a propagação de espécies com potencial energético, etapas de produção de bioenergia, usos do combustível e seus efeitos nos diversos tipos de motores. Agrupados por assunto, os textos estão distribuídos em cinco partes: Biomassa para bioenergia; Produção de biocombustíveis; Utilização de bioenergia; Biorrefinaria, alcoolquímica e oleoquímica e Sustentabilidade dos biocombustíveis