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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Avalia??o experimental e estudos a campo relacionados a Theileria equi (Laveran, 1901) Mehlhorn & Schein, 1998 em Canis familiaris no Munic?pio de Serop?dica Estado do Rio de Janeiro, Brasil / Experimental Assessment and Field studies about Theileria equi (Laveran, 1901) Mehlhorn & Schein, 1998 in Canis familiaris in municipality of Serop?dica State of Rio de Janeiro Brazil

Silva, Gil Vicente Oliveira da 19 April 2006 (has links)
Made available in DSpace on 2016-04-28T20:16:21Z (GMT). No. of bitstreams: 1 2006-Gil Vicente Oliveira da Silva.pdf: 2177431 bytes, checksum: 46c0c2291cd76db4f34ccb7eeaa34c10 (MD5) Previous issue date: 2006-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The equines piroplasmosis are diseases that may cause debilitating progress or fatal episodies, its etiologic agents are the species Theileria equi and Babesia caballi. The maintenance of these species in nature, as well as the widespread ability, are limitants factor to genetic improvement of equines herds in view of the internationals restrictions referring the accomited animals transit with these patogens. In Brazil, in economic terms these patogens have a great importance because the national erd is stimated in 5,800,000 of animals, that dropped with the asinines, arrive in 8,300,000 of animals. The eluciding of links to the natural disease history, overall the ones that propitiate the perpetuation of it in our herds, becomes urgent and necessary. Note that some species have a sight convivence with equines, among it is the Canis familiaris. With purpose to evaluate the possibility of C. familiaris to be involved on epizootiologic natural chain of T. equi, we used two boarding: experimental and epizootiologic. For the first, using material from seventeen dogs and puppies that were divided in three groups: G1 Puppies; G2 Dogs; G3 immunossuprimitted dogs and puppies, both ixodids-free since birth until end of experimental evaluations referring the possibility to C. Familiaris to be a able host to T. equi. to evaluate the occurrence of T. equi in these animals, were used some diagnostic tools, as follow: parasitologic aspect blood smears in immersion optical microscopy (IOM); sorology: using research of antibodies against T. equi, with immunofluorescence indirect test (IFT); and molecular using four differents protocols of polimerase chain reaction (PCR), in follow material: blood with EDTA; fragment of tissues; Boophilus microplus nymphs and Rhipicephalus sanguineus in adult stage. In the second moment, evaluated, for three times, twelve dogs from enzootic stability area to T. equi with a sight convivence with horses since birth occasions, using for it IMO and IFT, forming G4 group. The results were negatives in all observations. Concluding that the T. equi specie did not show the ability to establishment and development in C. Familiaris; and that specie do not involved in epizootiologic natural chain of T. equi, in municipality of Seropedica, State of Rio de Janeiro, Brazil. / As piroplasmoses eq?inas s?o doen?as que variam de progress?o debilitante a fatal, tendo como agentes causais ?s esp?cies Theileria equi e Babesia caballi. A manuten??o dessas esp?cies na natureza, bem como a habilidade de dispers?o das mesmas, s?o fatores limitantes quanto ao melhoramento gen?tico dos plant?is eq?inos tendo em vista as restri??es internacionais referentes ao tr?nsito de animais acometidos com estes pat?genos. No Brasil, em termos econ?micos estas parasitoses assumem grande vulto tendo em vista que o plantel nacional de eq?inos ? estimado em 5.800.000 de cabe?as que somado aos asininos chega-se ao total de 8.300.000. A elucida??o dos elos referentes ? hist?ria natural da doen?a, sobretudo os que propiciam a perpetua??o da mesma em nossos plant?is, torna-se urgente e necess?rio. Nota-se que algumas esp?cies mant?m um conv?vio estreito com eq??deos dentre as quais a Canis familiaris. Com o prop?sito de avaliar a possibilidade da esp?cie C. familiaris estar envolvida na cadeia epizootiol?gica da esp?cie T. equi, utilizamos duas abordagens: experimental e epizootiol?gica. Para a primeira, utilizando materiais procedentes de dezessete c?es adultos e filhotes os quais foram divididos em tr?s grupos: G1 C?es filhotes; G2 C?es adultos; G3 C?es adultos e filhotes imunossuprimidos, mantidos livres de ixod?deos, desde a ocasi?o do nascimento at? o t?rmino das avalia??es experimentais referentes ? possibilidade da esp?cie C. familiaris ser hospedeira vi?vel de T. equi. Para avaliar o estabelecimento da T. equi nestes animais, foram utilizadas para isto as seguintes ferramentas diagn?sticas: aspecto parasitol?gico - esfrega?os sangu?neos ? microscopia ?ptica de imers?o; sorol?gico - por meio de pesquisa de anticorpos anti-T. equi, utilizando a rea??o de imunofluoresc?ncia indireta (RIFI); e molecular, utilizando quatro diferentes protocolos de rea??o de polimeriza??o em cadeia (PCR), nos seguintes materiais: sangue total com EDTA; fragmentos de diversos ?rg?os; ninfas de Boophilus microplus e adultos de Rhipicephalus sanguineus. No segundo momento, Avaliou-se, por tr?s vezes, doze c?es provenientes de ?rea de estabilidade enzo?tica para T. equi com estreita conviv?ncia com cavalos desde a ocasi?o de seus nascimentos, utilizou-se para isto a MOI e RIFI, formando o grupo G4. Os resultados foram negativos em todas as observa??es. Conclui-se que a esp?cie T. equin?o se mostrou h?bil quanto ao estabelecimento e desenvolvimento em C. familiaris, e que esta esp?cie n?o est? envolvida na cadeia epizootiol?gica natural da T. equi, no Munic?pio de Serop?dica, Estado do Rio de Janeiro, Brasil.
2

Expressão heteróloga da EMA-2 de Theileria equi em Pichia pastoris / Heterologous Expression of Theileria equi EMA-2 protein in Pichia pastoris.

Vianna, Ana Muñoz 25 July 2011 (has links)
Made available in DSpace on 2014-08-20T13:32:58Z (GMT). No. of bitstreams: 1 dissertacao_ana_munhoz_vianna.pdf: 719262 bytes, checksum: c1b68d796b66c4c6c3d0037b6024cb3d (MD5) Previous issue date: 2011-07-25 / The equine piroplasmosis caused by Theileria equi is considered one of the most important equine diseases in both tropical and subtropical countries. Theileriosis is endemic in Brazil and causes significant economic losses for equine breeders. Disease-free countries restrict horse transit coming from endemic areas due to the high prevalence of asymptomatic carrier animals. In order to prevent and control this disease, it is therefore necessary to develop efficient diagnostic methods. Previous Theileria equi immunological diagnostic studies have been based in outer membrane antigens. Equi merozoite antigen (EMA) is a major outer membrane antigen of this protozoan, recognized by antibodies of Theileria equi positive horses. In this study, we reported the expression, purification and characterization of EMA-2 protein of Theileria equi in the yeast Pichia pastoris. The EMA-2 gene was cloned into the expression vector pPICZαB and the expressed protein was secreted to the medium as a soluble form. The expression and antigenicity of rEMA-2 protein was demonstrated by Dot and Western Blotting, using anti-histidine and equine Theileriosis clinically positive antibodies. An indirect ELISA with the rEMA-2 was performed and it was possible to differentiate with more than a threefold difference between negative and positive serum from horses confirmed with Theileriosis. The data obtained in this work suggest that the rEMA-2 protein expressed in P. pastoris is a potential candidate for use as antigen in immunodiagnostic of T. equi. / A Piroplasmose equina causada por Theileria equi é considerada uma das mais importantes doenças dos equinos em regiões tropicais e subtropicais. Acomete os equinos de forma endêmica no Brasil levando a significativas perdas econômicas. Países livres da doença não permitem a entrada de animais provindos de regiões endêmicas devido à alta prevalência de animais assintomáticos. Para controle e prevenção desta enfermidade se faz necessário desenvolvimento de métodos de diagnóstico eficazes. Os estudos sobre o diagnóstico imunológico para Theileriose concentram-se em antígenos da membrana externa. O principal antígeno da membrana externa deste protozoário, Equi Antígeno Merozoite (EMA) é reconhecido por anticorpos de cavalos positivos para Theileria equi. Neste estudo reportamos a expressão, purificação e a caracterização da proteína EMA-2 de Theileria equi na levedura Pichia pastoris. O gene EMA-2 foi clonado no vetor de expressão pPICZαB sendo a proteína expressa, secretada de forma solúvel ao meio. A expressão e antigenicidade da proteína rEMA-2 foi demonstrado por Dot e Western Blotting utilizando-se anti-histidina e anticorpos de equinos clinicamente positivos para Theileriose. Um ELISA indireto com rEMA-2 foi realizado e foi possível determinar uma diferença de mais de três vezes entre os soros de equinos confirmados como positivos e negativos para Theileriose. Com os dados obtidos neste trabalho podemos sugerir que a proteína rEMA-2 é um potencial candidato para ser utilizado como antígeno em imunodiagnóstico de T. equi.
3

Determinação da infecção por Theileria equi e Babesia caballi em equinos alojados no Jóquei Clube de São Paulo por meio da técnica de C-ELISA (Competitive Enzyme Lynked Immunosorbent Assay) / Evaluation of Theileria equi and Babesia caballi infections in equines housed at the Jockey Club in São Paulo city using C-ELISA test (Competitive Enzyme Lynked Immunosorbent Assay)

Marise Andri Piotto 11 December 2009 (has links)
Com o objetivo de avaliar os equinos alojados no Jóquei Clube de São Paulo, Brasil, quanto a presença de anticorpos contra Theileria equi e Babesia caballi, foram testadas 180 amostras de soro sanguíneo por meio da técnica de C-ELISA (Competitive Enzyme-Linked Immunosorbent Assay), metodologia atualmente recomendada pela OIE (Organização Internacional de Epizootíases) por ter alta sensibilidade e especificidade. A frequência de animais com sorologia positiva para Theileria equi foi de 6,66% (12/180), para Babesia caballi foi de 22,3% (40/180) e para infecção concomitante foi de 6,66% (12/180). Os resultados sorológicos obtidos por este estudo revelam que 35,5% (64/180) dos animais possuem anticorpos contra a babesiose equina sendo que a maioria dos animais acometidos tem dois e três anos de idade e portanto estão há menos tempo no hipódromo. Fatores como a ausência de carrapatos vetores, o uso de terapias babesicidas repetidas e o longo tempo de permanência dos animais no Jóquei após o tratamento, favorecem a diminuição dos títulos de anticorpos sem que ocorra reinfecção. Esses fatores podem justificar o menor número de animais com sorologia positiva para a doença nos cavalos com idade acima de quatro anos. Considerando-se esses resultados sugere-se que os animais sejam avaliados sorologicamente ao ingressarem no Jóquei Clube de São Paulo para que o uso de medicamentos contra a doença seja feito de forma adequada e para que os sinais clínicos compatíveis com babesiose equina em animais sorologicamente negativos sejam melhor avaliados e considerados em diagnósticos diferenciais. / In order to evaluate the presence of antibodies against Theileria equi and Babesia caballi in horses kept at the Jockey Club in São Paulo city, Brazil, a total of 180 samples of blood serum was tested using the Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA test). This methodology has been recommended by the International Organization of Epizooties (IOE) due to its high sensitivity and specificity. The frequency of seropositive animals for Theileria equi, Babesia caballi and for both was 6.66% (12/180), 22.3% (40/180) and 6.66% (12/180), respectively. Serological results showed that 35.5% of the animals (64/180) had antibodies against equine piroplasmosis; they were from two to three years old and were at the Jockey Club for a shorter period of time. Factors such as absence of thick vectors, repeated therapy using babesicidal drugs and the long period of time that the animals stayed in the Jockey Club after treatment favoured the lowering of antibody titers with no reinfection. These factors might be responsible for the fewer number of animals with positive serology for the disease in horses over four years of age. Based on these findings, animals should be serologically evaluated at the time of entrance into the Jockey Club so that the use of drugs against the disease be performed properly and clinical signs suggestive of equine babesiosis in serologically negative animals be better evaluated and considered for differential diagnosis.
4

Determinação da infecção por Theileria equi e Babesia caballi em equinos alojados no Jóquei Clube de São Paulo por meio da técnica de C-ELISA (Competitive Enzyme Lynked Immunosorbent Assay) / Evaluation of Theileria equi and Babesia caballi infections in equines housed at the Jockey Club in São Paulo city using C-ELISA test (Competitive Enzyme Lynked Immunosorbent Assay)

Piotto, Marise Andri 11 December 2009 (has links)
Com o objetivo de avaliar os equinos alojados no Jóquei Clube de São Paulo, Brasil, quanto a presença de anticorpos contra Theileria equi e Babesia caballi, foram testadas 180 amostras de soro sanguíneo por meio da técnica de C-ELISA (Competitive Enzyme-Linked Immunosorbent Assay), metodologia atualmente recomendada pela OIE (Organização Internacional de Epizootíases) por ter alta sensibilidade e especificidade. A frequência de animais com sorologia positiva para Theileria equi foi de 6,66% (12/180), para Babesia caballi foi de 22,3% (40/180) e para infecção concomitante foi de 6,66% (12/180). Os resultados sorológicos obtidos por este estudo revelam que 35,5% (64/180) dos animais possuem anticorpos contra a babesiose equina sendo que a maioria dos animais acometidos tem dois e três anos de idade e portanto estão há menos tempo no hipódromo. Fatores como a ausência de carrapatos vetores, o uso de terapias babesicidas repetidas e o longo tempo de permanência dos animais no Jóquei após o tratamento, favorecem a diminuição dos títulos de anticorpos sem que ocorra reinfecção. Esses fatores podem justificar o menor número de animais com sorologia positiva para a doença nos cavalos com idade acima de quatro anos. Considerando-se esses resultados sugere-se que os animais sejam avaliados sorologicamente ao ingressarem no Jóquei Clube de São Paulo para que o uso de medicamentos contra a doença seja feito de forma adequada e para que os sinais clínicos compatíveis com babesiose equina em animais sorologicamente negativos sejam melhor avaliados e considerados em diagnósticos diferenciais. / In order to evaluate the presence of antibodies against Theileria equi and Babesia caballi in horses kept at the Jockey Club in São Paulo city, Brazil, a total of 180 samples of blood serum was tested using the Competitive Enzyme-Linked Immunosorbent Assay (C-ELISA test). This methodology has been recommended by the International Organization of Epizooties (IOE) due to its high sensitivity and specificity. The frequency of seropositive animals for Theileria equi, Babesia caballi and for both was 6.66% (12/180), 22.3% (40/180) and 6.66% (12/180), respectively. Serological results showed that 35.5% of the animals (64/180) had antibodies against equine piroplasmosis; they were from two to three years old and were at the Jockey Club for a shorter period of time. Factors such as absence of thick vectors, repeated therapy using babesicidal drugs and the long period of time that the animals stayed in the Jockey Club after treatment favoured the lowering of antibody titers with no reinfection. These factors might be responsible for the fewer number of animals with positive serology for the disease in horses over four years of age. Based on these findings, animals should be serologically evaluated at the time of entrance into the Jockey Club so that the use of drugs against the disease be performed properly and clinical signs suggestive of equine babesiosis in serologically negative animals be better evaluated and considered for differential diagnosis.
5

Analyse du rôle des antigènes parasitaires solubles de Babesia canis dans la pathogénèse de la piroplasmose canine et caractérisation moléculaire de l’antigène Bc28.2 codé par la famille multigénique Bc28. / Analysis of the function of Babesia canis soluble parasite antigens during the pathogenesis of canine piroplasmosis and molecular characterization of the Bc28.2 antigen encoded by the Bc28 multigene family.

Finizio, Anne-Laure 14 December 2010 (has links)
Babesia canis est un hémoparasite du phylum des Apicomplexes transmis par la morsure de tique et responsable de la piroplasmose canine en Europe. Dans la perspective de développer un vaccin recombinant, nous avons réalisé deux études visant à mieux comprendre les interactions hôte/parasite au cours du cycle érythrocytaire. Nous avons étudié d'une part le rôle des antigènes parasitaires solubles (APS) dans le déclenchement des signes cliniques et d'autre part celui de l'antigène Bc28.2 codé par la famille multigénique Bc28 dans les mécanismes d'échappement à l'hôte.Les APS de B. canis induisent une réponse protectrice anti-maladie chez les chiens vaccinés. Toutefois, leur rôle exact dans la pathogénèse reste à définir. Contrairement à ce qui est décrit dans la pathogenèse à B. bovis, nos analyses réfutent l'hypothèse qu'ils pourraient agir sur le système kallicréine-kinine plasmatique. Par contre elles suggèrent, pour la première fois chez le genre Babesia, un rôle direct des APS dans le déclenchement précoce de la réponse inflammatoire observée au cours de la pathogenèse.De part leur fonction essentielle dans la survie parasitaire, les antigènes localisés à la surface de l'érythrocyte (rôle dans l'agglutination des hématies parasitées) ou des mérozoïtes (rôle dans l'invasion) sont de bons candidats vaccins. Cependant et probablement dans une perspective d'échappement à l'hôte, ils sont codés par des familles multigéniques. Chez B. canis, la famille multigénique Bc28 contient le gène Bc28.1 qui code pour un antigène à ancrage GPI préalablement caractérisé à la surface du mérozoïte. Nous montrons qu'un autre gène, désigné Bc28.2 (plusieurs copies dans le génome) contient 2 cadres de lecture chevauchant et serait capable d'exprimer des antigènes polymorphes de 28 kDa et 50 kDa par un mécanisme de recodage traductionnel +1. De façon originale, ces protéines seraient localisées non pas à la surface des mérozoïtes mais à la surface des hématies parasitées. / Babesia canis is an apicomplexan haemoparasite transmitted by tick bite and responsible of canine babesiosis in Europe. Understanding host/parasite relationships during the erythrocytic cycle is crucial for further development of a recombinant vaccine. In that way, the role of soluble parasite antigens (SPA) in the onset of clinical signs and the role of Bc28.2 antigen (encoded by the B. canis Bc28 multigene family) in host evading process were investigated.B. canis-derived SPA induce a protective anti-disease immunity in vaccinated dogs but their precise role during the pathogenesis remains unknown. In contrast to B. bovis, our analysis disproved the hypothesis that B. canis SPA could act on the plasma kallikrein-kinin system. However they strongly suggest, for the first time in the genus Babesia, a direct role of these SPA in the onset of the inflammatory response which is early observed during pathogenesis. Because of their essential function in the parasite survival, antigens located on the surface of infected erythrocyte (role in agglutination of erythrocytes) or on the surface of merozoites (role in the invasion) are good vaccine candidates.However, and probably for host evading, they are encoded by multigene families. In B. canis, the Bc28 multigene family contains the Bc28.1 gene that encodes for a GPI-anchored antigen previously characterized on the merozoite surface. We demonstrated here, that another gene designated Bc28.2, is multicopy and composed of two overlapping open reading frames (Orf1 and Orf2). It allows, though +1 programmed ribosomal frameshift, expression of polymorphic antigens of 28 kDa and 50 kDa. Unexpectedly, these proteins seem localized on the surface of parasitized erythrocytes, suggesting they play a crucial function in evading host through agglutination process of infected erythrocytes.

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