20 research outputs found
Expressão e análise antigênica da proteína RTP36 recombinante da amostra São Paulo de Ehrlichia canis para testes sorológicos
Ehrlichia canis is the main etiological agent of canine monocytic ehrlichiosis (CME), a globally canine infectious disease. In Brazil, CME is considered to be endemic, and its prevalence can reach 65% in some states. The diagnosis of ehrlichiosis is important for treatment and epidemiological purposes. The E. canis TRP36 (Tandem Repeat Protein) protein elicits the earliest acute-phase antibody response observed during the course of the disease. This study aimed to generate the recombinant TRP36 protein from E. canis São Paulo strain and to evaluate its potential as a tool for the serologic diagnosis of CME. The E. canis São Paulo isolate was cultivated in DH82 lineage cells, and its genomic DNA was obtained. The bacterial DNA fragment encoding the entire ORF of TRP36 was cloned into the pBAD/Thio-TOPO vector and transformed into Escherichia coli DH10B competent cells with the trp36-bearing plasmid for protein expression. To evaluate the protein antigenicity, 16 canine serum samples were previously tested (by PCR and the commercial SNAP4Dx serological test). The results were in accordance with the SNAP4Dx test. Experiments using this recombinant protein as an antigen, targeting the development of a serologic test based on ELISA methodology, are the next step to produce a reliable, affordable and useful diagnostic tool for CME in Brazil.Ehrlichia canis é o principal agente etiológico da erliquiose monocítica canina (EMC), uma doença infecciosa canina globalmente dispersa. No Brasil, a EMC é considerada endêmica, e a infecção pode atingir 65% em cães em alguns estados. O diagnóstico de erliquiose é importante para fins de tratamento e epidemiológicos. A proteína TRP36 de E. canis leva a uma resposta humoral com produção de anticorpos em fase aguda, encontrada durante o curso da doença. O objetivo deste estudo foi obter a proteína TRP36 recombinante da amostra São Paulo de E. canis e avaliar seu potencial como ferramenta para o diagnóstico sorológico da CME. O isolado de E. canis São Paulo foi cultivado em células da linhagem DH82 e o DNA genômico foi obtido. O fragmento de DNA bacteriano que codifica toda a ORF de TRP36 foi clonado no vetor pBAD / Thio-TOPO e transformado em células competentes Escherichia coli DH10B, com o plasmídeo portador de trp36 para expressão de proteínas. Para avaliar a antigenicidade da proteína, 16 amostras de soro canino foram previamente analisadas (por PCR e teste sorológico comercial SNAP4Dx). Os resultados estavam de acordo com o teste SNAP4Dx. Os experimentos que utilizam essa proteína recombinante como antígeno, visando ao desenvolvimento de um teste sorológico baseado no ELISA, são o próximo passo para produzir um teste de diagnóstico confiável, acessível e útil para o diagnóstico da EMC no Brasil
Molecular detection of Borrelia burgdorferi in free-living golden headed lion tamarins (Leontopithecus chrysomelas) in Rio de Janeiro, Brazil
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Predominance of Blastocystis spp, entamoeba histolytica /e.dispar and other protozoan evaluated through classical and molecular diagnostic techniques in two communities of Niterói-rj/Brazil. / Predominância de Blastocystis spp, entamoeba histolytica /e.dispar e outros protozoários avaliados através de técnicas de diagnóstico clássico e molecular em duas comunidades de Niterói-rj/Brazil
Background: Enteroparasites infections remains an important health issue in Brazil as contaminations are still detected among inhabitants of socially vulnerable populations of the country. This study was performed in two low income communities in Niterói, Rio de Janeiro State, Brazil. Methods: Health educational actions in two selected communities were performed and in parallel, 150 stool samples were collected. Coproparasitological diagnosis was carried out employing Hoffmann, Pons & Janer , Willis and Rugai techniques 5,6,7. Molecular diagnosis using Paglia & Visca protocol was performed to detect and differentiate E. histolytica/E.dispar infections 8. Results: Enteroparasites were found in more than 50% of the samples and protozoan infections prevailed. Blastocystis spp was the most prevalent protozoan (55.08%) followed by Endolimax nana (16.10%), Giardia lamblia (15.56%) and Entamoeba coli (11.02%). For helminth species, only Enterobius vermicularis and Strongyloides stercoralis were found, in 4.24% of positive samples. All samples were negative for E.histolytica/E. dispar infections through coproscopy, however, PCR analysis of 143 suitable stool samples showed that both species were present - as a complex or not - in 15% of the samples, in both institutions evaluated. Conclusions: The high frequency of protozoan infections may indicate extensive faecal-oral contamination. Additionally, it can ensure the basis for directed intervention actions in some communities to prevent water transmitted parasites providing sanitary infrastructure. Also, educational health programs for inhabitants of low income communities of Niterói, Rio de Janeiro State, Brazil, are necessary in order to provide a better understanding of enteroparasites and its prophylatic measures.
Detecção e caracterização molecular de piroplasmas em cães naturalmente infectados no Sudeste do Brasil
Rangelia vitalii é um protozoário que infecta cães e foi descrito nas regiões Sul e Sudeste do Brasil. R. vitalii é filogeneticamente próxima à Babesia spp., mas dados deste misterioso parasito ainda são escassos. O objetivo deste trabalho foi detectar a presença de piroplasmas em cães naturalmente infectados no estado do Rio de Janeiro, através da amplificação do gene 18S rRNA pela PCR, clivagem com enzimas de restrição (RFLP) e caracterização genética através do sequenciamento. De 103 cães, sete (6,8%) foram positivos para Babesia spp. pela PCR. Os produtos amplificados foram digeridos por enzimas de restrição para a diferenciação das espécies de Babesia e uma amostra foi identificada como Babesia vogeli. O padrão de amplificação observado nas outras seis amostras não correspondeu ao padrão descrito para babesias que infectam cães. O sequenciamento das seis amostras confirmou ser uma espécie geneticamente idêntica a R. vitalii apresentando grande homologia (99-100%) com a sequência do sul do Brasil. Este estudo confirma a presença de Babesia vogeli e Rangelia vitalii infectando cães em Teresópolis, Rio de Janeiro, Brasil.Rangelia vitalii is a protozoon described from dogs in the south and southeast regions of Brazil. It is phylogenetically related to Babesia spp. that infects dogs, but data on this enigmatic parasite is still limited. The aim of this work was to detect piroplasm species in dogs in the state of Rio de Janeiro, Brazil, by 18S rRNA gene-based PCR assay, restriction fragment length polymorphism (RFLP) and sequence analyses. Of 103 dogs examined, seven (6.8%) were positive for Babesia spp. by PCR. The amplified products were digested by restriction enzymes to differentiate the Babesia species, and one sample was identified as Babesia vogeli. The pattern observed for the other six amplification products did not match with pattern described for large Babesia infecting dogs. Sequencing analysis confirmed these six samples as R. vitalii, with high homologies (99-100%) with a sequence from south Brazil. This study confirms the presence of Babesia vogeli and Rangelia vitalii circulate in domestic dogs in Teresópolis, Rio de Janeiro, Brazil
Frequency and molecular characterisation of Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii, and Entamoeba hartmanni in the context of water scarcity in northeastern Brazil
Colonização de ecótopos artificiais pelo Panstrongylus megistus na ilha de Santa Catarina, Florianópolis, Santa Catarina, Brasil
The aim of this work was to verify the colonization of Panstrongylus megistus on artificial ecotopes in Florianópolis, in the Santa Catarina Island, South Brazil. For this purpose 443 houses of the Lagoa district and 779 house annexes (524 chicken-houses, 46 corrals and 209 storage-houses) in 9 different places were examined from 1985 to 1992. These ecotopes, which include ceilings and basements, were checked after application of dislodging liquid (Pirisa 5%). Colonization by P. megistus was verified in two houses, three chicken-houses and one storage-house of the Lagoa district, where eggs, nymphs and adults were collected. To verify local reports of P. megistus occurrence, another two houses and one school were investigated. The colonization at all of these places was confirmed. In the 9 artificial ecotopes examined, 559 eggs, 305 nymphs and 24 adults were collected. The infection rate of P. megistus by Trypanosoma cruzi was 55.3% (182/ 329). A similar infection rate of 56.5% (78/138) was obtained in adults of P. megistus from sylvatic ecotopes and in adults captured in the houses by the inhabitants between 1983 to 1991. Precipitin tests revealed blood from just one source in 94.0% of the insects (170/181). Human blood was found in 80.6% (25/31) of the adults and in 5.8% (1/17) of the nymphs captured in the houses. These results suggest the need to ally serious epidemiologic vigilance to the effort of the inhabitants in order to avoid the risk of domiciliation of P. megistus in the houses.Objetivando verificar a colonização de Panstrongylus megistus em ecótopos artificiais em Florianópolis foram examinados, de 1985 a 1992, 779 anexos peridomiciliares (524 galinheiros, 46 currais e 209 ranchos) em 9 localidades e 443 domicílios no distrito de Lagoa, todos na Ilha de Santa Catarina. Todo o ecótopo, incluindo forro e porão das casas, era examinado após aplicação de líquido insentífugo (Pirisa a 5%). A pesquisa nos anexos peri-domiciliares revelou 3 galinheiros e um rancho positivo no distrito de Lagoa, onde foram também encontrados 2 domicílios colonizados pelo P. megistus, com a captura de ovos, ninfas e adultos em todos os ecótopos. Pesquisas dirigidas foram realizadas em dois outros domicílios e em uma escola, nos quais os moradores haviam detectado anteriormente exemplares de P. megistus e, em todos os 3, foi confirmada a colonização pelo triatomíneo. Nos 9 ecótopos artificiais foram coletados 559 ovos, 305 ninfas e 24 adultos de P. megistus, com um índice de infecção pelo T. cruzi de 53,3% (182/329). Índice de infecção semelhante, de 56,5% (78/ 138), foi também encontrado nos adultos de P. megistus oriundos dos ecótopos silvestres e capturados nos domicílios pelos moradores, no período de 1983 a 1991. Os testes de precipitina revelaram, em 94,0% dos insetos examinados (170/181), sangue de uma única fonte alimentar e presença de sangue humano em 80,6% (25/31) dos adultos e em 5,8% (1/17) das ninfas capturados nos domicílios. Os resultados encontrados sugerem a necessidade de adoção de medidas de vigilância epidemiológica com a participação da comunidade, face o risco potencial de domiciliação do P. megistus
Biological and Genetic Heterogeneity in Trypanosoma dionisii Isolates from Hematophagous and Insectivorous Bats
This study describes the morphological, biochemical, and molecular differences among Trypanosoma dionisii isolates from hemocultures of hematophagous (Desmodus rotundus; n = 2) and insectivorous (Lonchorhina aurita; n = 1) bats from the Atlantic Rainforest of Rio de Janeiro, Brazil. Fusiform epimastigotes from the hematophagous isolates were elongated, whereas those of the insectivorous isolate were stumpy, reflected in statistically evident differences in the cell body and flagellum lengths. In the hemocultures, a higher percentage of trypomastigote forms (60%) was observed in the hematophagous bat isolates than that in the isolate from the insectivorous bat (4%), which demonstrated globular morphology. Three molecular DNA regions were analyzed: V7V8 (18S rDNA), glycosomal glyceraldehyde 3-phosphate dehydrogenase gene, and mitochondrial cytochrome b gene. The samples were also subjected to multilocus enzyme electrophoresis and random amplified polymorphic DNA analysis. All isolates were identified as T. dionisii by phylogenetic analysis. These sequences were clustered into two separate subgroups with high bootstrap values according to the feeding habits of the bats from which the parasites were isolated. However, other T. dionisii samples from bats with different feeding habits were found in the same branch. These results support the separation of the three isolates into two subgroups, demonstrating that different subpopulations of T. dionisii circulate among bats
Evaluation of Molecular Variability of Isolates of <em>Trypanosoma cruzi</em> in the State of Rio de Janeiro-Brazil
Trypanosoma cruzi, the etiological agent of Chagas disease, presents considerable heterogeneity among populations of isolates within the sylvatic and domestic cycle. This study aims to evaluate the genetic diversity of 14 isolates collected from specimens of Triatoma vitticeps from Triunfo, Conceição de Macabu, and Santa Maria Madalena cities (Rio de Janeiro—Brazil). By using PCR based on the mini-exon gene, all isolates showed a profile characteristic of bands zymodeme III and with a lower intensity characteristic of TcII. To verify possible hybrids among the strains analyzed, the polymorphisms analysis of the MSH2 gene was performed. HhaI restriction enzyme digestion products resulted in characteristic TcII fragments only, demonstrating the absence of hybrids strains. In our attempt to characterize isolation in accordance with the reclassification of T. cruzi into six new groups called DTUs (“discrete typing unit”), we genotyped the mitochondrial cytochrome oxidase subunit two gene, ribosomal RNA gen (24Sα rDNA), and the spliced leader intergenic region (SL-IR). This procedure showed that TcII, TcIII, and TcIV are circulating in this area. This highlights the diversity of parasites infecting specimens of T. vitticeps, emphasizing the habit of wild type and complexity of the region epidemiological study that presents potential mixed populations
Clinical and hematological evaluation of Rangelia vitalii-naturally infected dogs in southeastern Brazil
Abstract Rangelia vitalii, a tick-borne piroplasm that infects dogs, has been recently molecularly characterized in Brazil, Uruguay and Argentina. Studies on molecular characterization of these piroplasms in different Brazilian regions are scarce. The aim of this study was to evaluate clinical and hematological changes in dogs caused by R. vitalii in the mountainous region of the state of Rio de Janeiro. Blood samples from 36 dogs were evaluated for piroplasms and hematological disorders using light microscopy and molecular analysis. Blood samples from all the animals included in this study were confirmed to be positive for R. vitalii through genetic sequencing. Clinical signspresented by 24 of the 36 dogs of the study were evaluated during appointments or hospitalization within private practice. The most frequent clinical disorders in these dogs that were naturally infected with R. vitalii were fever, spontaneous cutaneous bleeding and diarrhea. Normochromic non-regenerative anemia and thrombocytopenia were the most common hematological disorders in these R. vitalii-positive dogs and therefore should be considered in hematological evaluations on suspected cases
Pesquisa de hemoglobinopatias em cães da região metropolitana do Rio de Janeiro portadores de anemia crônica
RESUMO: Talassemias e hemoglobinopatias são condições hereditárias encontradas em humanos de todo o mundo. Em medicina veterinária, o polimorfismo de hemoglobinas tem sido estudado em animais de produção, mas não existem relatos de hemoglobinopatias em cães, e os estudos envolvendo o polimorfismo de hemoglobinas nesta espécie são escassos. Com o objetivo de pesquisar variantes da hemoglobina em cães, foram coletadas amostras de sangue de 202 caninos de variadas raças, sendo 130 portadores de anemia crônica (Grupo Experimental) e 72 animais clinicamente saudáveis (Grupo Controle). Estas amostras foram submetidas à eletroforese alcalina de hemoglobinas, que permitiu a separação e quantificação das frações de hemoglobina por densitometria, e posteriormente submetidas à eletroforese de hemoglobinas em meio ácido, técnica utilizada em medicina humana para a separação de frações de hemoglobinas variantes que não se diferenciam em meio alcalino. O eritrograma e índices hematimétricos foram obtidos concomitantemente. Os métodos utilizados demonstraram que a HbA é o maior componente da hemoglobina canina, e que uma pequena quantidade de HbA2 pode ser detectada em uma parcela dos animais avaliados, sendo que a maioria dos caninos apresentava exclusivamente HbA em sua composição. Concluiu-se que a presença ou ausência de HbA2 não interfere nos índices hematimétricos dos animais avaliados, e que quando comparadas as hemoglobinas dos grupos Experimental e Controle, não são observadas diferenças na distribuição das frações destas, além de não serem observadas hemoglobinas variantes nos caninos avaliados