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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.
21

Avaliação da resposta de anticorpos contra antígenos de Plasmodium vivax relacionada a fatores genéticos do parasito e do hospedeiro humano /

Melo, Luciane Moreno Storti de. January 2011 (has links)
Orientador: Ricardo Luiz Dantas Machado / Banca: Cláudio Tadeu Daniel Ribeiro / Banca: Érika Martins Braga / Banca: Claudia Regina Bonini Domingos / Banca: Érika Cristina Pavarino Bertelli / Resumo: O presente estudo avaliou a resposta de anticorpos contra diferentes antígenos de merozoíto e esporozoíto de Plasmodium vivax, relacionando com as variantes da porção repetitiva do domínio central do gene da Proteína Circunsporozoítica (CSP) do parasito (VK210, VK247 e P. vivax-like) e com os polimorfismos do HLA-DRB1 no hospedeiro humano. A resposta de anticorpos foi avaliada para peptídeos das regiões conservadas e centrais variáveis da CSP, da porção N-terminal da Proteína de Superfície do Merozoíto 1-MSP1 (Pv200L), e recombinante do Antígeno 1 de Membrana Apical (AMA-1) e a Proteína de ligação ao Duffy (DBP) por ELISA, em amostras de plasma de pacientes naturalmente infectados com P. vivax. Inicialmente nós avaliamos a distribuição destas variantes da CSP em cinco diferentes áreas da Amazônia a fim de entender sua atual dinâmica de transmissão. A variante VK210 continua sendo a mais prevalente em todas as áreas estudadas. No entanto, pela primeira vez documentamos a presença das variantes VK247 e P. vivax-like como infecções simples na Amazônia brasileira evidenciando um novo perfil distribuição destas, o que possa sugerir um processo de adaptação das mesmas. Quando comparamos a resposta de anticorpos e a infecção pelas variantes de P. vivax, não foram observadas associações significativas entre a presença de determinada variante da CSP e a freqüência de resposta de anticorpos contra os três peptídeos do merozoíto analisados, MSP1 (Pv200L), AMA-1 e DBP e nem contra as frações conservadas da CSP no esporozíto, N-terminal [N] e C-terminal [C]. A falta de associações significativas entre resposta sorológica contra esses peptídeos fornece informações promissoras quanto à utilização destes antígenos para o desenvolvimento de uma vacina contra malária. Todavia, a variação na porção central da CSP deve ser considerada... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study evaluated the antibody response against merozoite and sporozoite antigens of Plasmodium vivax and its relationship with the variants of the repetitive central region of the gene for Circunsporozoite protein (CSP) in parasite (VK210, VK247 and P. vivax-like) and, with the HLA-DRB1 polymorphisms in human host. The antibody response to synthetic peptides of the CSP conserved and variable regions and of the N-terminal portion of Merozoite surface protein - MSP1 (Pv200L), and, to recombinants peptides of the Apical Membrane Antige 1 (AMA-1) and of the Duffy Binding Protein (DBP) was evaluable by ELISA in plasma samples of malaria patients naturally infected with P. vivax. Firstly, we evaluated the CSP variants distribution among five different areas from Brazilian Amazon, in order to understand their current dynamic of transmissions. VK210 variant remains the most prevalent in all study areas. However, it is the first detection of VK247 e P. vivax-like variants as simple infection in the Brazilian Amazon, showing a new distribution profile, which may suggest an adaptation process of them. When comparing the antibody response and infection by variants of P. vivax, there were no significant associations between the presence of particular CSP variant and the frequency of antibody response against all three merozoite peptides analyzed, MSP1 (Pv200L), AMA-1, DBP and against the CSP conserved fractions in the sporozoite, N-terminal and C-terminal. The lack of significant associations among immune response against these peptides provides promising information regarding the use of these antigens for malaria vaccine development. On the other hand, the central variability of CSP should be considered to employment of this region as an immunogen, since the antibody response appears to be variant-specific. In order to evaluate the polymorphisms... (Complete abstract click electronic access below) / Doutor
22

COVID-19 v Domově ve Břevnici / SARS-CoV-2 in Care Home Břevnice

Myslivcová, Lenka January 2021 (has links)
The aim of this diploma thesis was to describe information about SARS-CoV-2 virus and coronavirus disease (COVID-19), to evaluate the course of the disease in the Home with a special regime in Břevnice, in which the epidemic took place at the beginning of the first wave of COVID-19 pandemic in spring 2020. Another goal was to perform an antibody analysis and evaluate the obtained data. I divided the diploma thesis into three main parts: theoretical, experimental and discussion. In the theoretical part, I worked with the literature and described information related not only to COVID-19, but also to other serious infections caused by human coronaviruses. In the experimental part, which I performed in the immunological laboratory of the Department of Joint Laboratories at Havlíčkův Brod Hospital, I dealt with the issue of the clinical course of the disease, the severity of the disease and possible consequences after the infection. I also dealt with methods for the determination of antibodies, the principles of which are described in Chapter 4.5. The diagnostic methods and procedures used are described in Chapter 5.3 Laboratory Assays. From the obtained data, I prepared graphs and tables and processed data on the clinical course of the infection in the Břevnice Home, both for the clients and the...
23

Identificação de marcadores genéticos associados às imunidades celular, humoral e aos status clínico e de infecção natural pela Leishmania (Leishmania) infantum em cães / Identification of genetic markers associated to clinical, antibody and cellmediated reponses to natural Leishmania (Leishmania) infantum infection in dogs

Batista, Luís Fábio da Silva 22 March 2016 (has links)
A infecção de cães pela Leishmania (Leishmania) infantum resulta em um espectro de manifestações imunopatológicas que dependem da interação parasito hospedeiro e são definidas por fatores ambientais e pela genética do hospedeiro. Apesar disso, a imunogenética da leishmaniose visceral canina (LVC) permanece inexplorada. Nós realizamos diagnóstico laboratorial, clínico, ensaio de linfoproliferação (LPA), quantificação de citocinas, teste de hipersensibilidade tardia à leishmanina (LST), quantificação de IgA, IgE, IgG, IgM anti L. (L. ) infantum, IgG anti saliva de flebotomíneo e genotipagem ampla afim de identificar polimorfismos de nucleotídeo único (SNPs) associados aos diferentes perfis de imunidades celular, humoral, resposta clínica e status de infecção em cães de área endêmica, utilizando modelo de componente de variância (EMMAX). O efeito de estrutura da amostra foi controlado em todas as análises. A presença ou ausência de infecção pela L. (L. ) infantum foi associado a regiões contendo os genes PRGR_CANFA, RAB38, NOX4, PRKCI e SMAD7, IL1RA, IL12A_CANFA relacionados à ativação de fagócitos, mecanismos microbicidas, sobrevivência intracelular de patógenos e resposta pró inflamatória; a resposta clínica foi associada a regiões contendo os genes CATA_CANFA, LIAS, IL17A e IL17F relacionados à proteção contra danos do estresse oxidativo e indução de resposta pró inflamatória; o resultado LST+ foi associado à resposta Th1, controle da infecção mas não preveniu a manifestação de sinais clínicos, enquanto o LST- foi associado à resposta Treg e aumento do parasitismo. O resultado do LST foi associado a regiões contendo os genes MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 envolvidos com maturação de fagócitos, migração e adesão de leucócitos, estabilidade da sinapse imunológica, diferenciação e proliferação de linfócitos. A linfoproliferação foi dependente da carga parasitária e associada a regiões contendo os genes FOCAD, PIAS2, SMAD2 e IL6R envolvidos com supressão tumoral e diferenciação de linfócitos Th17 ou Treg; o aumento dos níveis de IgA, IgE e IgG anti L. (L. ) infantum foi associado à LVC sintomática enquanto o de IgG anti saliva de Lutzomyia longipalpis foi associado à exposição e infecção assintomática. Quanto à resposta de IgM, foram identificados SNPs nos genes NXN e SH3BP5 relacionados com inibição do crescimento, diferenciação e ativação de linfócitos B e vias de sinalização de TLR4 e TLR9; para IgG anti - L. (L. ) infantum foram identificadas regiões contendo os genes IL17RB, SH2B3 e replicação do loci de susceptibilidade NOX4, RAB38, CTSC envolvidos com linfopoiese, citocinese, resposta pró inflamatória, mecanismos microbicidas, sobrevivência intracelular de Leishmania; os níveis de IgA foram associados a regiões contendo os genes LIN28A e MAFB implicados na predisposição à nefropatia glomerular, já os níveis de IgG anti saliva de Lu. longipalpis foram associados a regiões contendo os genes ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 envolvidos com supressão celular, produção de imunoglobulina via TLR4 e sobrevivência intracelular de Leishmania. Esses resultados apontam regiões cromossômicas úteis para a elucidação da resposta à infecção por L. (L. ) infantum em cães e alvos potenciais para estudos funcionais, estratégias profiláticas e terapêuticas / Leishmania (Leishmania) infantum infection in dogs leads to a range of immunopathological responses, which depend on a parasite - host interaction and are defined by environmental factors and genetic of host. Neverthless, immunogenetic of the canine leishmaniasis (CanL) remains unexplored. We performed diagnosis and clinical evaluation, lymphoproliferation assay (LPA), leishmanin skin test (LST), quantification of cytokine, anti-L. (L. ) infantum IgA, IgE, IgG, IgM, anti- sandfly saliva IgG levels and genome wide association scan of 110.165 SNPs (GWAS) in order to indentify loci associated to clinical, antibody, cell-mediated responses and status of infection in 189 dogs, employng a expedited efficient mix model of association (EMMAX). Control of stratification effects due to sample structure was evideced by the low inflation factors. Status of infection was associated to SNPs in linkage desequilibrium (LD) with PRGR_CANFA, RAB38, NOX4, PRKCI and in the neighborhood of SMAD7, IL1RA, IL12A_CANFA genes related to phagocyte maturation, killing of pathogens and proinflamatory response; clinical outcome was associated to CATA_CANFA, LIAS, IL17A, IL17F loci involved in prevention of oxidative burst mediated injury and proinflamatory response; LST+ was associated to Th1 response although it has not prevented symptoms, whereas LST- was associated to Treg response and enhanced parasite load. Overall, LST response was associated to MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 loci committed to phagocyte maturation, leukocyte adhesion and migration, stability in immunological synapse, lymphocyte diferenciation and proliferation. Lymphocyte proliferation was rely on parasit burden and associated to FOCAD, PIAS2 loci in the neighborhood of SMAD2 e IL6R genes, wich are implicated in tumor supression and Treg/Th17 decision; Increased levels of anti-L. (L. ) infantum IgA, IgE, IgG were observed in severity of CanL. In contrast, anti- sandfly saliva IgG was enhenced in asymptomatic dogs. IgM response was associated to NXN e SH3BP5 loci related to fate, growing and activation of B cells; anti-L. (L. ) infantum IgG levels was associated to region containing IL17RB, SH2B3 and replication of NOX4, RAB38, CTSC suscptibility loci involved in proinflamatory response, microbicidal activity, lymphopoiesis and cytokinesis; IgA levels were associated to SNPs on LIN28A and MAFB, wich are implicated glomerular nephropathy, whereas anti-sandfly saliva IgG levels were associated to ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 loci, wich are related to supression of inflamation, antibody response through the TLR4 pathway and survival of intracellular pathogens. These findins provide insights for responses to L. (L. ) infantum infection and point to potential targets for functional investigations, therapeutic and prophylactic strategies
24

Identificação de marcadores genéticos associados às imunidades celular, humoral e aos status clínico e de infecção natural pela Leishmania (Leishmania) infantum em cães / Identification of genetic markers associated to clinical, antibody and cellmediated reponses to natural Leishmania (Leishmania) infantum infection in dogs

Luís Fábio da Silva Batista 22 March 2016 (has links)
A infecção de cães pela Leishmania (Leishmania) infantum resulta em um espectro de manifestações imunopatológicas que dependem da interação parasito hospedeiro e são definidas por fatores ambientais e pela genética do hospedeiro. Apesar disso, a imunogenética da leishmaniose visceral canina (LVC) permanece inexplorada. Nós realizamos diagnóstico laboratorial, clínico, ensaio de linfoproliferação (LPA), quantificação de citocinas, teste de hipersensibilidade tardia à leishmanina (LST), quantificação de IgA, IgE, IgG, IgM anti L. (L. ) infantum, IgG anti saliva de flebotomíneo e genotipagem ampla afim de identificar polimorfismos de nucleotídeo único (SNPs) associados aos diferentes perfis de imunidades celular, humoral, resposta clínica e status de infecção em cães de área endêmica, utilizando modelo de componente de variância (EMMAX). O efeito de estrutura da amostra foi controlado em todas as análises. A presença ou ausência de infecção pela L. (L. ) infantum foi associado a regiões contendo os genes PRGR_CANFA, RAB38, NOX4, PRKCI e SMAD7, IL1RA, IL12A_CANFA relacionados à ativação de fagócitos, mecanismos microbicidas, sobrevivência intracelular de patógenos e resposta pró inflamatória; a resposta clínica foi associada a regiões contendo os genes CATA_CANFA, LIAS, IL17A e IL17F relacionados à proteção contra danos do estresse oxidativo e indução de resposta pró inflamatória; o resultado LST+ foi associado à resposta Th1, controle da infecção mas não preveniu a manifestação de sinais clínicos, enquanto o LST- foi associado à resposta Treg e aumento do parasitismo. O resultado do LST foi associado a regiões contendo os genes MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 envolvidos com maturação de fagócitos, migração e adesão de leucócitos, estabilidade da sinapse imunológica, diferenciação e proliferação de linfócitos. A linfoproliferação foi dependente da carga parasitária e associada a regiões contendo os genes FOCAD, PIAS2, SMAD2 e IL6R envolvidos com supressão tumoral e diferenciação de linfócitos Th17 ou Treg; o aumento dos níveis de IgA, IgE e IgG anti L. (L. ) infantum foi associado à LVC sintomática enquanto o de IgG anti saliva de Lutzomyia longipalpis foi associado à exposição e infecção assintomática. Quanto à resposta de IgM, foram identificados SNPs nos genes NXN e SH3BP5 relacionados com inibição do crescimento, diferenciação e ativação de linfócitos B e vias de sinalização de TLR4 e TLR9; para IgG anti - L. (L. ) infantum foram identificadas regiões contendo os genes IL17RB, SH2B3 e replicação do loci de susceptibilidade NOX4, RAB38, CTSC envolvidos com linfopoiese, citocinese, resposta pró inflamatória, mecanismos microbicidas, sobrevivência intracelular de Leishmania; os níveis de IgA foram associados a regiões contendo os genes LIN28A e MAFB implicados na predisposição à nefropatia glomerular, já os níveis de IgG anti saliva de Lu. longipalpis foram associados a regiões contendo os genes ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 envolvidos com supressão celular, produção de imunoglobulina via TLR4 e sobrevivência intracelular de Leishmania. Esses resultados apontam regiões cromossômicas úteis para a elucidação da resposta à infecção por L. (L. ) infantum em cães e alvos potenciais para estudos funcionais, estratégias profiláticas e terapêuticas / Leishmania (Leishmania) infantum infection in dogs leads to a range of immunopathological responses, which depend on a parasite - host interaction and are defined by environmental factors and genetic of host. Neverthless, immunogenetic of the canine leishmaniasis (CanL) remains unexplored. We performed diagnosis and clinical evaluation, lymphoproliferation assay (LPA), leishmanin skin test (LST), quantification of cytokine, anti-L. (L. ) infantum IgA, IgE, IgG, IgM, anti- sandfly saliva IgG levels and genome wide association scan of 110.165 SNPs (GWAS) in order to indentify loci associated to clinical, antibody, cell-mediated responses and status of infection in 189 dogs, employng a expedited efficient mix model of association (EMMAX). Control of stratification effects due to sample structure was evideced by the low inflation factors. Status of infection was associated to SNPs in linkage desequilibrium (LD) with PRGR_CANFA, RAB38, NOX4, PRKCI and in the neighborhood of SMAD7, IL1RA, IL12A_CANFA genes related to phagocyte maturation, killing of pathogens and proinflamatory response; clinical outcome was associated to CATA_CANFA, LIAS, IL17A, IL17F loci involved in prevention of oxidative burst mediated injury and proinflamatory response; LST+ was associated to Th1 response although it has not prevented symptoms, whereas LST- was associated to Treg response and enhanced parasite load. Overall, LST response was associated to MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 loci committed to phagocyte maturation, leukocyte adhesion and migration, stability in immunological synapse, lymphocyte diferenciation and proliferation. Lymphocyte proliferation was rely on parasit burden and associated to FOCAD, PIAS2 loci in the neighborhood of SMAD2 e IL6R genes, wich are implicated in tumor supression and Treg/Th17 decision; Increased levels of anti-L. (L. ) infantum IgA, IgE, IgG were observed in severity of CanL. In contrast, anti- sandfly saliva IgG was enhenced in asymptomatic dogs. IgM response was associated to NXN e SH3BP5 loci related to fate, growing and activation of B cells; anti-L. (L. ) infantum IgG levels was associated to region containing IL17RB, SH2B3 and replication of NOX4, RAB38, CTSC suscptibility loci involved in proinflamatory response, microbicidal activity, lymphopoiesis and cytokinesis; IgA levels were associated to SNPs on LIN28A and MAFB, wich are implicated glomerular nephropathy, whereas anti-sandfly saliva IgG levels were associated to ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 loci, wich are related to supression of inflamation, antibody response through the TLR4 pathway and survival of intracellular pathogens. These findins provide insights for responses to L. (L. ) infantum infection and point to potential targets for functional investigations, therapeutic and prophylactic strategies
25

Développement d’un biomarqueur salivaire mesurant l’exposition de l’Homme aux piqûres des moustiques Aedes : applications aux risques de transmission et à l’évaluation de l’efficacité des stratégies de lutte contre les arboviroses / Development of a salivary biomarker for measuring the human exposure to Aedes mosquitoes bites : applications to evaluate the risk of arboviruses transmission and the efficacy of vector control

Elanga N'Dille, Clément Emmanuel 20 May 2014 (has links)
Les infections virales transmises à l'homme par les moustiques Aedes, sont en pleine émergence ou ré-émergence dans le monde entier. Le contrôle des populations de vecteurs reste la seule méthode de lutte. Pour un contrôle plus efficace, de nombreux efforts sont déployés pour développer de nouveaux indicateurs évaluant l'exposition de l'Homme aux piqûres des Aedes. Dans ce contexte, l'objectif de la thèse était de développer un biomarqueur, basé sur l'évaluation quantitative de la réponse anticorps (Ac) spécifique au peptide salivaire Nterm-34kDa d'Ae. aegypti chez les populations exposées. Pour cela, nous avons évalué le potentiel de cette réponse Ac spécifique à i) mesurer l'intensité d'exposition aux piqûres, ii) évaluer le risque de transmission des arboviroses et iii) évaluer l'efficacité des stratégies de lutte anti-vectorielle (LAV). Nos résultats ont montré qu'une réponse IgG anti-peptide Nterm-34kDa pouvait être détectée chez les individus exposés à Ae. aegypti et Ae. albopictus. Le niveau de cette réponse IgG spécifique augmentait entre les saisons de faibles densités de moustiques et celles de fortes densités, indiquant que ce candidat biomarqueur permettrait d'évaluer l'exposition aux piqûres des Aedes. La distribution spatiale similaire de la prévalence de nouvelles infections au virus de la dengue et la prévalence de la réponse IgG spécifique montrait également que ce candidat biomarqueur permettrait d'identifier des zones à risque de transmission. La comparaison des réponses IgG anti-peptide Nterm-34kDa avant et après les interventions de LAV, a montré qu'une baisse post-LAV de cette réponse Ac spécifique permettrait d'évaluer l'efficacité de la LAV contre les Aede. Ce biomarqueur salivaire pourrait donc représenter un indicateur de la réduction du contact homme-vecteur. L'ensemble de ces travaux montre que la réponse Ac spécifique au peptide salivaire Nterm-34kDa constitue un pertinent biomarqueur pour évaluer l'exposition de l'Homme aux vecteurs des arboviroses. La validation supplémentaire de ce biomarqueur et son développement sous forme de test rapide permettraient aux structures en charge de la surveillance des arboviroses et de la lutte anti-vectorielle, de disposer d'un outil complémentaire des indicateurs entomologiques et épidémiologiques de référence. / Human viral infections transmitted by Aedes mosquitoes are rapidly emerging or re-emerging worldwide. Vector control strategies remain currently the unique method to control these infections. To improve the effectiveness of this control, much effort is being devoted to develop new indicators for measuring the human exposure to Aedes bites. In this way, this project aimed to develop a biomarker based on the quantitative assessment of antibody response (Ab) to Ae. aegypti Nterm - 34kDa salivary peptide, in human exposed populations. We evaluated thus the potential of this specific Ab response to: i) measure the intensity of human exposure to Aedes bites, ii) assess the risk of transmission of arboviruses and iii) evaluate the efficacy of vector control strategies. Our results showed that a specific IgG response to Nterm-34kDa peptide could be detected in individuals exposed to Ae. aegypti or Ae. albopictus. The level of specific IgG response increased from the season of low mosquito densities to high densities one, indicating that this biomarker candidate could evaluate the intensity of exposure to the Aedes bites. The observed similar spatial distribution of the prevalence of new infections with dengue virus and specific IgG response showed that this biomarker candidate could identify areas at risk of transmission. The comparison of the specific IgG responses to Nterm-34kDa peptide before and after the vector control intervention showed a decline of the specific Ab response after implementation of control. It indicated that such salivary biomarker could assess the effectiveness of vector control against Aedes, and that this salivary biomarker could be an indicator of the reduction of man-vector contact. Altogether, the results of this work show that the specific IgG response to the Nterm-34kDa salivary peptide could be a relevant biomarker for assessing human exposure to arboviruses vectors. This promising indicator, developed as a rapid test, could represent a complementary tool for entomological and epidemiological surveillance of arboviruses diseases.
26

Marqueurs d'exposition aux piqûres de moustiques du genre Culex et processus physiopathologiques d'infection au virus de West Nile / Markers of exposure to Culex mosquito bites and pathophysiological processes of West Nile virus infection

Bakli, Mahfoud 25 November 2013 (has links)
Le virus West Nile,WNV est responsable de milliers de cas de morbidité et de mortalité chez les oiseaux, les chevaux et l’homme. Le WNV se transmet par des moustiques du genre Culex. Les méthodes entomologiques ne permettent pas l’évaluation individuelle directe du contact hôte/vecteur. 5 protéines salivaires de Culex ont été sélectionnées, produites, et évaluées comme des candidats antigéniques de l'exposition aux piqûres de Culex. Des sérums humains du sud de France exposés à des densités de Culex distinctes et des sérums de chevaux exposés à l'infection par le WNV ont été testés. Une protéine 30kD est reconnue par les chevaux exposés à Culex. Cependant, pas de différence de réponse d’anticorps n’a été observée entre les animaux faiblement et fortement exposés. Concernant les processus physiopathologiques de la maladie causée par le WNV, la cinétique des profils d'expression de protéines de l’hôte dans le cerveau de souris infectées par le WNV, a été étudiée sur des échantillons prélevés avant et après l’apparition des signes cliniques, en utilisant 2D-DIGE et iTRAQ. 148 protéines différentiellement exprimées. Les voies de signalisation altérées au cours de l'infection précoce et tardive ont été identifiées. Les profils protéiques de LCR de patients atteints de WNND et des individus témoins ont été comparés, en utilisant l’approche iTRAQ. 47 protéines ont été trouvées différemment exprimées chez les patients WNND. Un candidat potentiel biomarqueur, la Defensine-alpha1, a été évalué par ELISA sur des échantillons humains de LCR/sérum. Les biomarqueurs putatifs identifiés dans cette étude peuvent être un outil précieux d’évaluation de la mesure de la gravité du WNV. / West Nile Virus,WNV is responsible for thousands of cases of morbidity and mortality in birds, horses and humans. WNV is transmitted mainly by mosquitoes by Culex species, to avian hosts. Entomological methods did not give direct individual evaluation of the host/vector contact. 5 salivary proteins from the Culex genus were selected for a production under recombinant forms for further evaluation as potential antigenic candidates of exposure to Culex bites. Sera from individuals living in south of France exposed to distinct Culex density and sera from horses exposed to WNV infection were tested. The recombinant protein30 kDa was recognized only by horses exposed to Culex. However, no difference of antibody response between low and high exposed to Culex. Concerning the pathophysiological processes of WNV disease, a kinetics host brain protein expression profiles of WNV-infected mice using samples collected prior and after clinical signs apparition was performed using proteomic approaches 2D-DIGE and iTRAQ. 148 distinct proteins was found altered following WNV infections. The functional signaling networks in samples collected during early and late infection have been identified. Un examination of CSF protein profiles between patients with neuroinvasive disease (WNND) and control individuals was performed using iTRAQ approach. 47 proteins were found differentially expressed in WNND patients compared to controls. A potential biomarker candidates, defensin-alpha1 was assessed by ELISA using other human paired CSF/serum samples. The putative biomarker identified in this study may potentially be a valuable tool in the assessment of the extent of WNV severity.
27

Vlastnosti slinných proteinů flebotomů rodu Sergentomyia a Phlebotomus / Comparison and characterization of salivary proteins from Sergentomyia and Phlebotomus sand flies

Polanská, Nikola January 2020 (has links)
Sand flies (Diptera, Phlebotominae) are small biting insects and vectors of Leishmania spp. which cause medically and veterinary important disease - leishmaniasis. During the piercing of the host skin, sand fly females inject saliva to facilitate the blood feeding. The sand fly saliva is composed of many bioactive molecules which were shown to possess anti-inflammatory and anti-haemostatic functions. The saliva affects host's immunity in the bite site and consequently enhances the survival and development of transmitted pathogens. Most of the studies focus on salivary proteins and enzymes of sand flies belonging to Phlebotomus and Lutzomyia genera, while salivary proteins from sand flies of the third genus Sergentomyia were neglected so far. In this thesis we focused on comparison of salivary proteins from two Phlebotomus species, namely Phlebotomus perniciosus and Phlebotomus orientalis, and Sergentomyia schwetzi. These sand fly species differ not only by the ecology and geographical distribution but also by host preferences. Both Phlebotomus species prefer large or medium-size mammals as the bloodmeal source, particularly rabbits, hares and dogs for P. perniciosus and cattle, goats, sheep and humans for P. orientalis. Contrarily, Sergentomyia sand flies are known for preferred feeding on reptiles...
28

Avaliação do sistema complemento e produção de anticorpos de pacientes HIV negativos com neurocriptococose / Antibody response to Cryptococcus sp and complement system activation in HIV negative patients with neurocryptococcosis

Arruk, Viviana Galimberti 31 October 2011 (has links)
Cryptococcus sp é um fungo saprófita, cosmopolita, que causa micose sistêmica, geralmente, subaguda ou crônica, conhecida, sobretudo, por sua localização meníngea, após aquisição da infecção por via respiratória Embora seja ubíquo, a criptococose ocorre predominantemente em indivíduos imunodeficientes e podendo ocorrer, também, em indivíduos imunocompetentes. Os estudos experimentais e em humanos avaliando a ativação do sistema complemento e a produção de anticorpos específicos mostram que a resposta inata e de anticorpos são importantes para a delimitação do processo infeccioso por Cryptococcus sp, como também, a administração de anticorpos monoclonais podem induzir uma resposta eficaz na disseminação da doença. O sistema complemento contribui para a defesa do organismo contra o Cryptococcus sp de diferentes maneiras: secretando opsoninas e fatores quimiotáticos e colaborando com a ação dos anticorpos específicos, aumentando a interação entre a imunidade inata e adquirida. Os anticorpos antiglicuroxilomanana (GXM) possuem numerosas atividades biológicas: a) opsonização para fagocitose, b) ativação da via clássica do complemento resultando na deposição precoce de fragmentos de C3 no fungo, c) supressão do excesso de acúmulo de C3 pela via alternativa; d) facilitação do clareamento do GXM do soro in vivo, resultando no maior acúmulo de GXM nos tecidos ricos em células do sistema fagocítico mononuclear; e) proteção em modelos murinos da criptococose e f) facilitação de vários aspectos da imunidade celular ao Cryptococcus sp. O objetivo desse estudo foi avaliar a resposta humoral ao GXM e às proteínas da parede celular (Ag S) avaliando a atividade do sistema complemento como também a produção de anticorpos específicos em amostras séricas de adultos com e sem neurocriptococose. Foram coletadas 106 amostras de soro e divididas em 3 grupos: grupo 1- 21 indivíduos com neurocriptococose e baixa exposição a levedura, grupo 2- foi composto por 23 indivíduos saudáveis com alta exposição ao fungo e HIV negativos, granjeiros da cidade de Jumirim localizada a 164 km de São Paulo, na região de Sorocaba e, o grupo 3- 60 indivíduos saudáveis, HIV negativos e com baixa exposição ao Cryptococcus sp. Dois pacientes foram excluídos do estudo por apresentarem tumores (timona e câncer de pulmão). O sistema complemento foi avaliado por ensaio hemolítico (CH 50 e AP 50) e, a dosagem da proteína ligadora de manose (MBL) foi feita por ELISA. Os valores de CH 50 estiveram dentro da normalidade em 17/21, 13/23, 59/60 indivíduos dos grupos 1, 2 e 3 respectivamente. A média dos valores de CH 50 foi diferente significativamente entre o três grupos (P < 0,0001). O grupo 2 mostrou níveis reduzidos significantes em comparação aos dois outros grupos. Os valores de AP 50 estiveram dentro da normalidade em 11/21; 21/23 e 60/60 indivíduos dos grupos 1, 2 e 3 respectivamente. Houve diferença nos valores de AP 50 (P = 0,0005) e apenas um paciente do grupo 1 apresentou valores indetectáveis desta via. Houve diferença significante na dosagem de MBL entre os três grupos (P = 0,0277). Anticorpos IgG anti-GXM foram quantificados por ELISA e expressos por densidade óptica (DO). IgG anti GXM foi detectado em todos os grupos com diferença significante entre eles (P= 0,0127). As médias de IgG anti- GXM (DO) foram: 1.191 (0,49 a 1.217) no grupo 1, 1.572 (0,815 a 2.479) no grupo 2 e 0,965 (0,321 a 1.295) no grupo 3. Dois indivíduos assintomáticos do grupo 2 tiveram títulos de GXM detectáveis (1/256 e 1/32). Quatro pacientes com neurocriptococose faleceram (19%) e seus resultados mostravam: CH 50 normal, 2/4 tinham valores de AP 50 baixo (12 UI/mL) e indetectável; 3/4 tinham altos níveis de MBL e apenas um tinha baixa DO de IgG anti-GXM. Baseado em nosso estudo, podemos concluir que a resposta humoral (sistema complemento e anticorpos) não é suficiente para explicar a susceptibilidade a neurocriptococose, porém a alta e constante exposição ao Cryptococcus sp pode prevenir o desenvolvimento de doença, ou seja, a constante e intensa exposição ao fungo induz a produção de anticorpos que previnem a doença clínica mas não a infecção. Por outro lado fatores genéticos que determinam as concentrações de MBL podem influenciar na susceptibilidade a neurocriptococose. Os anticorpos contribuem para o clearence de GXM, entretanto as concentrações séricas não se correlacionam com resistência à doença / Cryptococcus sp is a fungal pathogen with a worldwide distribution. Although it is ubiquitous in the environment, cryptococcal disease occurs predominantly in immunocompromised hosts and can also occur in apparently immunocompetent individuals. The innate immunity is of special relevance for the antifungal reaction, as it allows an immediate reaction and recognizes a broad variety of fungal pathogens. The host immune response is a major determinant of the outcome of cryptococcal infection; however, the antibodies response is poorly understood. In addition, most of the studies are experimental and there is restricted knowledge concerning the human immune response. Complement system has soluble factors, restrictive regulator proteins and cellular receptors involved in defense mechanism. Glucuroxylomannan (GXM) monoclonal antibodies (MAbs) have numerous biological activities: a) opsonization for phagocytosis, b) activation of the classical complement pathway leading to early deposition of C3 fragments on the yeast, c) suppression overall accumulation of C3 via the alternative pathway; d) clearance facilitation of GXM from serum in vivo, leading to increased accumulation of GXM in tissues rich in mononuclear phagocyte system; e) protection in murine models of cryptococcosis and f) facilitation of various aspects of cellular immunity to Cryptococcus sp. The goal of our study was to evaluate if the antibody response to GXM and cell wall proteins regarding specific antibodies as well as complement system in sera of immunocompetent adults with and without neurocryptococcosis. The aim of our research was to evaluate classical and alternative complement system pathway, to quantify mannose-binding lectin (MBL) as well antibody response to GXM and cell wall proteins (AgS) regarding specific antibodies in sera of immunocompetent adults with and without neurocryptococcosis. One hundred and six samples were collected and classified in 3 groups: group 1- 21 individuals with neurocryptococcosis and low exposure to the yeast; group 2- was composed by 23 healthy individuals, chicken farmings from Jurumirim, a town 164 km to São Paulo, and with high exposure to Cryptoccocus spp and HIV negative. The third group included 60 healthy HIV negative individuals with presumed low exposure to Cryptococcus. Two patients were excluded by report of previous malignancies (timoma and pulmonary cancer). The complement system was evaluated by hemolytic assay and ELISA to MBL. CH 50 and AP 50 values were within the normal range in 17/21; 13/23; 59/60 patients in groups 1, 2 and 3 respectivelly. Mean CH 50 values were significantly different among the three groups (P < 0,0001). Group 2 showed significantly reduced levels in comparison with groups 1 and 3. AP 50 values were within the normal range in 11/21; 21/23; 60/60 patients in groups 1, 2 and 3 respectivelly. There was difference in the AP 50 values (P=0,0005) and one no activation of this pathway in group 1. There was significant difference in MBL among the groups (P = 0,0277). GXM antibodies IgG was measured by ELISA and expressed as optical density (OD). GXM- IgG was detected in all the groups with significant difference among them (P = 0,0127). The means of IgG anti-GXM (OD) were: 1.191 (range 0,49 to 1.217) in group 1, 1.572 (range 0,815 to 2.479) in group 2 and 0,965 (range 0,321 to 1.295) in the group 3. Two of the group 2 individuals had low GXM titers (1/256 and 1/32) and no symptoms. Four patients (4/21; 19%) with neurocryptococcosis died and the results showed: normal classical pathway activation, 2/4 had low (12 UI/mL) or undetectable alternative pathway values ; 3/4 had high MBL concentrations and only one had low OD for IgG anti-GXM. In conclusion, our results suggest that constant and high exposure to Cryptococcus sp can prevent the development of cryptococcosis, i.e. constant and intensive fungal exposition induces protective antibodies to clinical disease but not to the infection. In the other side, genetic factors which determine MBL concentrations could influence the susceptibility to neurocryptococcosis. The antibodies contribute to GXM clearance, however, the concentrations did not correlate with the resistance to the disease
29

Avaliação do sistema complemento e produção de anticorpos de pacientes HIV negativos com neurocriptococose / Antibody response to Cryptococcus sp and complement system activation in HIV negative patients with neurocryptococcosis

Viviana Galimberti Arruk 31 October 2011 (has links)
Cryptococcus sp é um fungo saprófita, cosmopolita, que causa micose sistêmica, geralmente, subaguda ou crônica, conhecida, sobretudo, por sua localização meníngea, após aquisição da infecção por via respiratória Embora seja ubíquo, a criptococose ocorre predominantemente em indivíduos imunodeficientes e podendo ocorrer, também, em indivíduos imunocompetentes. Os estudos experimentais e em humanos avaliando a ativação do sistema complemento e a produção de anticorpos específicos mostram que a resposta inata e de anticorpos são importantes para a delimitação do processo infeccioso por Cryptococcus sp, como também, a administração de anticorpos monoclonais podem induzir uma resposta eficaz na disseminação da doença. O sistema complemento contribui para a defesa do organismo contra o Cryptococcus sp de diferentes maneiras: secretando opsoninas e fatores quimiotáticos e colaborando com a ação dos anticorpos específicos, aumentando a interação entre a imunidade inata e adquirida. Os anticorpos antiglicuroxilomanana (GXM) possuem numerosas atividades biológicas: a) opsonização para fagocitose, b) ativação da via clássica do complemento resultando na deposição precoce de fragmentos de C3 no fungo, c) supressão do excesso de acúmulo de C3 pela via alternativa; d) facilitação do clareamento do GXM do soro in vivo, resultando no maior acúmulo de GXM nos tecidos ricos em células do sistema fagocítico mononuclear; e) proteção em modelos murinos da criptococose e f) facilitação de vários aspectos da imunidade celular ao Cryptococcus sp. O objetivo desse estudo foi avaliar a resposta humoral ao GXM e às proteínas da parede celular (Ag S) avaliando a atividade do sistema complemento como também a produção de anticorpos específicos em amostras séricas de adultos com e sem neurocriptococose. Foram coletadas 106 amostras de soro e divididas em 3 grupos: grupo 1- 21 indivíduos com neurocriptococose e baixa exposição a levedura, grupo 2- foi composto por 23 indivíduos saudáveis com alta exposição ao fungo e HIV negativos, granjeiros da cidade de Jumirim localizada a 164 km de São Paulo, na região de Sorocaba e, o grupo 3- 60 indivíduos saudáveis, HIV negativos e com baixa exposição ao Cryptococcus sp. Dois pacientes foram excluídos do estudo por apresentarem tumores (timona e câncer de pulmão). O sistema complemento foi avaliado por ensaio hemolítico (CH 50 e AP 50) e, a dosagem da proteína ligadora de manose (MBL) foi feita por ELISA. Os valores de CH 50 estiveram dentro da normalidade em 17/21, 13/23, 59/60 indivíduos dos grupos 1, 2 e 3 respectivamente. A média dos valores de CH 50 foi diferente significativamente entre o três grupos (P < 0,0001). O grupo 2 mostrou níveis reduzidos significantes em comparação aos dois outros grupos. Os valores de AP 50 estiveram dentro da normalidade em 11/21; 21/23 e 60/60 indivíduos dos grupos 1, 2 e 3 respectivamente. Houve diferença nos valores de AP 50 (P = 0,0005) e apenas um paciente do grupo 1 apresentou valores indetectáveis desta via. Houve diferença significante na dosagem de MBL entre os três grupos (P = 0,0277). Anticorpos IgG anti-GXM foram quantificados por ELISA e expressos por densidade óptica (DO). IgG anti GXM foi detectado em todos os grupos com diferença significante entre eles (P= 0,0127). As médias de IgG anti- GXM (DO) foram: 1.191 (0,49 a 1.217) no grupo 1, 1.572 (0,815 a 2.479) no grupo 2 e 0,965 (0,321 a 1.295) no grupo 3. Dois indivíduos assintomáticos do grupo 2 tiveram títulos de GXM detectáveis (1/256 e 1/32). Quatro pacientes com neurocriptococose faleceram (19%) e seus resultados mostravam: CH 50 normal, 2/4 tinham valores de AP 50 baixo (12 UI/mL) e indetectável; 3/4 tinham altos níveis de MBL e apenas um tinha baixa DO de IgG anti-GXM. Baseado em nosso estudo, podemos concluir que a resposta humoral (sistema complemento e anticorpos) não é suficiente para explicar a susceptibilidade a neurocriptococose, porém a alta e constante exposição ao Cryptococcus sp pode prevenir o desenvolvimento de doença, ou seja, a constante e intensa exposição ao fungo induz a produção de anticorpos que previnem a doença clínica mas não a infecção. Por outro lado fatores genéticos que determinam as concentrações de MBL podem influenciar na susceptibilidade a neurocriptococose. Os anticorpos contribuem para o clearence de GXM, entretanto as concentrações séricas não se correlacionam com resistência à doença / Cryptococcus sp is a fungal pathogen with a worldwide distribution. Although it is ubiquitous in the environment, cryptococcal disease occurs predominantly in immunocompromised hosts and can also occur in apparently immunocompetent individuals. The innate immunity is of special relevance for the antifungal reaction, as it allows an immediate reaction and recognizes a broad variety of fungal pathogens. The host immune response is a major determinant of the outcome of cryptococcal infection; however, the antibodies response is poorly understood. In addition, most of the studies are experimental and there is restricted knowledge concerning the human immune response. Complement system has soluble factors, restrictive regulator proteins and cellular receptors involved in defense mechanism. Glucuroxylomannan (GXM) monoclonal antibodies (MAbs) have numerous biological activities: a) opsonization for phagocytosis, b) activation of the classical complement pathway leading to early deposition of C3 fragments on the yeast, c) suppression overall accumulation of C3 via the alternative pathway; d) clearance facilitation of GXM from serum in vivo, leading to increased accumulation of GXM in tissues rich in mononuclear phagocyte system; e) protection in murine models of cryptococcosis and f) facilitation of various aspects of cellular immunity to Cryptococcus sp. The goal of our study was to evaluate if the antibody response to GXM and cell wall proteins regarding specific antibodies as well as complement system in sera of immunocompetent adults with and without neurocryptococcosis. The aim of our research was to evaluate classical and alternative complement system pathway, to quantify mannose-binding lectin (MBL) as well antibody response to GXM and cell wall proteins (AgS) regarding specific antibodies in sera of immunocompetent adults with and without neurocryptococcosis. One hundred and six samples were collected and classified in 3 groups: group 1- 21 individuals with neurocryptococcosis and low exposure to the yeast; group 2- was composed by 23 healthy individuals, chicken farmings from Jurumirim, a town 164 km to São Paulo, and with high exposure to Cryptoccocus spp and HIV negative. The third group included 60 healthy HIV negative individuals with presumed low exposure to Cryptococcus. Two patients were excluded by report of previous malignancies (timoma and pulmonary cancer). The complement system was evaluated by hemolytic assay and ELISA to MBL. CH 50 and AP 50 values were within the normal range in 17/21; 13/23; 59/60 patients in groups 1, 2 and 3 respectivelly. Mean CH 50 values were significantly different among the three groups (P < 0,0001). Group 2 showed significantly reduced levels in comparison with groups 1 and 3. AP 50 values were within the normal range in 11/21; 21/23; 60/60 patients in groups 1, 2 and 3 respectivelly. There was difference in the AP 50 values (P=0,0005) and one no activation of this pathway in group 1. There was significant difference in MBL among the groups (P = 0,0277). GXM antibodies IgG was measured by ELISA and expressed as optical density (OD). GXM- IgG was detected in all the groups with significant difference among them (P = 0,0127). The means of IgG anti-GXM (OD) were: 1.191 (range 0,49 to 1.217) in group 1, 1.572 (range 0,815 to 2.479) in group 2 and 0,965 (range 0,321 to 1.295) in the group 3. Two of the group 2 individuals had low GXM titers (1/256 and 1/32) and no symptoms. Four patients (4/21; 19%) with neurocryptococcosis died and the results showed: normal classical pathway activation, 2/4 had low (12 UI/mL) or undetectable alternative pathway values ; 3/4 had high MBL concentrations and only one had low OD for IgG anti-GXM. In conclusion, our results suggest that constant and high exposure to Cryptococcus sp can prevent the development of cryptococcosis, i.e. constant and intensive fungal exposition induces protective antibodies to clinical disease but not to the infection. In the other side, genetic factors which determine MBL concentrations could influence the susceptibility to neurocryptococcosis. The antibodies contribute to GXM clearance, however, the concentrations did not correlate with the resistance to the disease
30

Études chimiques et immunologiques des capsules polysaccharidiques de Streptococcus suis

Goyette-Desjardins, Guillaume 12 1900 (has links)
No description available.

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