• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 205
  • 164
  • 62
  • 19
  • 13
  • 13
  • 8
  • 6
  • 6
  • 5
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 561
  • 114
  • 85
  • 70
  • 53
  • 52
  • 52
  • 51
  • 50
  • 50
  • 48
  • 47
  • 44
  • 44
  • 44
  • 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.
121

Associação dos polimorfismos de IFN-lambda 4, KIR e HLA-C em pacientes vivendo com HTLV-1 / Association of IFN-lambda 4, KIR and HLA-C polymorphisms in HTLV-1 subjects

Tatiane Assone dos Santos 07 November 2016 (has links)
As doenças virais têm sido importantes causas de morbidade e mortalidade nas últimas décadas, sendo que algumas delas são relacionadas com polimorfismos genéticos, que determinam a susceptibilidade do hospedeiro ou a resistência a essas infecções, influenciando na patogênese, além de desempenhar importante papel em respostas ao tratamento. Entre elas, destaca-se o HTLV-1, sendo que cerca de 10 a 20 milhões de pessoas em todo o mundo possuem esse vírus. Apenas 5% dos indivíduos infectados desenvolverão algum tipo de doença relacionada a tal infecção, entre elas destaca-se a HAM/TSP. Apesar da complexidade, o entendimento das interações hospedeiro versus HTLV-1 é de fundamental importância para avaliar prognóstico clínico dos portadores assintomáticos, visto que as opções diagnósticas e de tratamento não são adequadas, até o momento, para determinar o risco de progressão para HAM/TSP. Com isso, este trabalho objetivou estudar a associação entre alguns marcadores virais, genéticos e imunológicos relacionados ao desenvolvimento de HAM/TSPem pacientes infectados por HTLV-1. O ambulatório de HTLV do Instituto de Infectologia \"Emilio Ribas\" (IIER) possui uma coorte de portadores de HTLV em seguimento há 19 anos, para o presente estudo foram selecionados 247 voluntários portadores de HTLV-1, por conveniência. Somente pacientes adultos, com seguimento ativo no ambulatório no período de junho de 2011 até julho de 2016 foram convidados a participar. Este protocolo foi aprovado pelo CEP do IIER (Nº13/2011), e o TCLE foi obtido de todos os voluntários participantes. Os indivíduos foram classificados de acordo com seu quadro clínico neurológico em dois grupos: Grupo I (160 assintomáticos) e Grupo II (87 HAM/TSP). Amostra de sangue venoso foi coletada e as células mononucleares separadas. O material foi utilizado para o ensaio de PVL e para a genotipagem de IFN-?4, HLA-C e KIR, pela técnica de qPCR . A análise estatística no modelo multivariado mostrou associação de risco para HAM/TSP com as variáveis LPA (p=0,001) e a idade (p=0,019), além disso, o polimorfismo doIFN-?4 no rs8099917 foi associado no modelo recessivo(OR=0,31, IC=0,105 - 0,961) como fator de proteção ao desfecho.:Esse modelo estudado explica 8% dos fatores de progressão e de proteção para HAM/TSP. Desse modo, estudos genéticos multicêntricos envolvendo análise de exoma e maior número de casos de HAM/TSP, deveriam ser realizados. O entendimento da patogênese da mielopatia pode oferecer marcadores de valor prognóstico importantes para o manejo clínico, além de contribuir para o achado de novas intervenções terapêuticas no futuro. / The viral diseases have been major causes of morbidity and mortality in recent decades, some of which are related to genetic polymorphisms, which determine the susceptibility or resistance to these infections, influencing the pathogenesis, besides of playing an important role in responses to treatment. Among them, it is highlighted HTLV-1, in which around 10 to 20 million people worldwide. Only 5% of infected subjects will develop some kind of disease related to such infection, including HAM/TSP. Despite the complexity, the understanding of host interactions versus HTLV-1 is fundamental importance to evaluate clinical prognosis of asymptomatic subjects, once the diagnostic options and treatment are not adequate, so far, to determine the risk of progression to HAM/TSP. Therefore, the purpose of this study was to investigate the association among some genetic polymorphisms, viral and immunological markers related to the development of HAM/TSP in HTLV-1-infected subjects. At the Institute of Infectious Diseases \"Emilio Ribas\" (IIER) has a cohort of HTLV subjects followed up for 19 years, for this study 247 volunteers with HTLV-1were selected for convenience. Only adult patients with active follow up in the period from June 2011 to July 2016 were invited to participate. This protocol was approved by the ethical committee at IIER (nº13/2011), informed consent was obtained. Subjects were classified according to their neurological status in two groups: Group I (160 asymptomatic) and Group II (87 HAM / TSP). Blood sample was collected and PBMCs The DNA was used to the PVL assay and IFN-?4, HLA-C and KIR genotyping using qPCR. It has been observed an association to HAM/TSP with LPA variables (p=0.001) and age (p=0.019) in the multivariable analysis. On the other hand, the polymorphism of IFN-?4 rs8099917 was associated in the recessive model (OR=0.31, CI=0.105-0.961) as a protective factor to HAM/TSP. This study explains 8% of progression and protective factors for HAM/TSP. Thus, multi-center studies involving genetic analysis and more cases of HAM/TSP, should be done. The understanding of the HAM/TSP pathogenesis can provide important markers of prognostic value for clinical management and contribute to the discovery of new therapeutic interventions in the future.
122

Functional characterizations of the psoriasis candidate gene HCR. / 銀屑病相關基因HCR的功能鑒定 / CUHK electronic theses & dissertations collection / Yin xie bing xiang guan ji yin HCR de gong neng jian ding

January 2006 (has links)
Although early studies on HCR provided valuable information for its characterization, the functions of HCR remain unclear. / In addition, we also isolated HCR partners in keratinocyte using a yeast two-hybrid screening. Two novel HCR partners, keratin 17 and nm23-H2, were identified. Since the expression of keratin 17 in epidermis has been recognized as a hallmark of psoriatic plaques, our findings support HCR as a candidate gene for psoriasis susceptibility. We speculate that nm23-H2 is involved in endocytosis together with HCR because nm23 also participated in endocytotic pathways. / In this study, we attempted to relate the function of HCR gene to its role in the pathogenesis of psoriasis. We first examined the subcellular localization of HCR. From a series of co-localization experiments, we eventually localized HCR in early endosomes because almost completely overlapped with active Rab4 which regulates vesicle traffic from early endosomes to perinuclear recycling endosomes and to the plasma membrane indicating that HCR may regulate sorting of internalized cargo from early endosomes to the recycling endosomes or back to the cytoplasm. / Psoriasis is a common chronic skin disorder affecting approximately 1-2% of the Caucasian population. A genetic basis for psoriasis susceptibility has been determined, however, the genetic influence of psoriasis is complex. Several genetic linkage studies have been identified. PSORS1 at 6p21.3 which has been narrowed down to a few hundred kilobase intervals around the HLA-C is the most consistently observed susceptibility locus for psoriasis in both linkage analyses and genome wide scans. HCR is a candidate gene lying within the HLA region which was previously named PG8 for 'putative gene 8' and is now more commonly called HCR for 'alpha-helix coiled-coil rod homolog'. The HCR gene is highly polymorphic. SNP association analysis showed that one SNP haplotype, named HCR*WWCC (corresponding to SNPs at nucleotides 307, 325, 1723, 2327, and involving amino acids 103, 109, 575 and 776, respectively), was associated with psoriasis. Early studies showed that the protein was confined to basal keratinocytes in healthy and non-lesional skin, whereas, it was expressed above the tips of basal and suprabasal dermal papillae in psoriatic lesional skin. / Li, Chunman. / "November 2005." / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0810. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 137-149). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / School code: 1307.
123

Polimorfismo do HLA-G na transmissão materno-infantil do HIV-1 / HLA-G polymorphism in mother-child transmission of HIV-1

Sanches, Roberta Seron 14 December 2012 (has links)
A principal via de infecção pelo HIV-1 em crianças é a transmissão materno-infantil (TMI). Estimativas para taxas de TMI do HIV-1 são de 3% entre gestantes sob terapia antirretroviral e de 25 a 30% para as não tratadas. Apesar da exposição viral durante a gestação, a maioria dos recém-nascidos não são verticalmente infectados, o que sugere a existência de barreiras protetoras à TMI do HIV-1. Diversos fatores podem estar associados com a TMI do HIV-1. Polimorfismos genéticos são descritos em associação com a infecção pelo HIV-1, incluindo os dos antígenos leucocitários humanos (HLA). A molécula HLA-G tem sido implicada nas interações imunológicas materno-fetais e é expressa em células da placenta, especificamente nos citotrofoblastos extravilosos, que formam a camada responsável pela interface entre os tecidos fetais e maternos. Este estudo avaliou os polimorfismos de inserção e deleção de 14pb do HLA-G na TMI do HIV-1. Participaram do estudo, 86 duplas de mães e filhos, sendo 58 duplas de mãe-filho em que a TMI do HIV-1 não ocorreu e 28 duplas em que a TMI ocorreu. Os resultados mostraram maior frequência de genótipo deleção/deleção em mães pertencentes ao grupo TMI positiva, sem utilização de antirretrovirais (p=0,05). Foi observada associação significante entre conhecimento prévio da soropositividade, realização de pré-natal, utilização de antirretrovirais na gestação e não amamentação com a prevenção da TMI (p<0,05). Nesse contexto, a enfermagem pode contribuir com ações que envolvem o pré-natal, parto e puerpério, por meio de aconselhamento quanto à realização do teste anti- HIV-1 no pré-natal, utilização adequada de antirretrovirais e promoção de práticas ideais de alimentação infantil. Adicionalmente, o estudo contribui para a ampliação de conhecimentos da enfermagem sobre a temática do HLA-G na TMI, e destaca a importância de que a enfermagem, fundamentada em ciências biológicas, esteja envolvida na produção de conhecimentos e tecnologias, o que reflete na melhoria da prestação do cuidado ao paciente. / The main way of HIV-1 infection in children is mother-child transmission (MTCT). TMI rates estimates for HIV-1 are 3% in pregnant women in antiretroviral therapy and 25 to 30% for untreated ones. Despite the viral exposure during pregnancy, most newborns are not vertically infected, suggesting the existence of protective barriers to TMI of HIV-1. Several factors may be associated with MTCT of HIV-1. Genetic polymorphisms are described in association with HIV-1, including the human leukocyte antigens (HLA). The molecule HLA-G has been implicated in maternal-fetal immune interactions and is expressed in placenta cells, particularly in extravillous cytotrophoblasts, forming the layer responsible for the interface between fetal and maternal tissues. This study evaluated the HLA-G 14pb insertion and deletion polymorphisms in MTCT of HIV-1. Participated in the study 86 mother-child pair, 58 mother-child pairs in which the MTCT did not occur and 28 doubles in which the MTCT occurred. The results showed a higher frequency of genotype deletion/deletion in mothers in which MTCT occurred belonging to the group without using antiretroviral (p=0.05). Significant association was observed between prior knowledge of seropositivity, conducting prenatal, use of antiretroviral during pregnancy and not breastfeeding to the prevention of MTCT (p <0.05). In this context, nursing can contribute to actions involving prenatal, birth and postpartum, conducting counseling for the conduct of HIV testing during prenatal care, proper use of antiretroviral and promotion of optimal infant feeding practices. Additionally, the study contributes to the expansion of nursing knowledge about the topic of HLA-G in MTCT, and highlights the importance of nursing, grounded in basic sciences, is involved in the production of knowledge and technology, which reflects improvement in the provision of patient\'s care.
124

Relevância da monitorização dos anticorpos anti-HLA após o transplante renal: estudo clínico e anatomopatológico / Relevance of anti-HLA monitoring after kidney transplantation: Clinical and anatomopathological study

Souza, Patrícia Soares de 29 January 2009 (has links)
INTRODUÇÃO: O objetivo deste estudo foi avaliar prospectivamente os anticorpos anti-HLA após o transplante renal e associar estes achados com episódios de rejeição aguda, marcação por C4d e sobrevida do enxerto. MÉTODOS: Foram avaliados 926 soros de 111 pacientes no primeiro ano pós-transplante ou até a perda do enxerto. Os anticorpos foram analisados por PRA-ELISA (Panel Reactive Antibodies by Enzyme Linked Immuno Sorbent Assay). Anticorpos anti-HLA doador-específicos foram detectados por provas-cruzadas e caracterizados pelo método de microesferas marcadas com antígenos HLA. Episódios de rejeição aguda foram classificados conforme os Critérios de Banff 97, atualizados em 2003. RESULTADOS: Conforme o PRA-ELISA pós-transplante os pacientes foram classificados em 5 Grupos: Grupo A (n=80): sem evidência de anticorpos pré e pós-transplante; Grupo B (n=8): pacientes com anticorpos de novo; Grupo C (n=5): pacientes sensibilizados que permaneceram com mesmo nível de PRA-ELISA; Grupo D (n=4): pacientes sensibilizados que elevaram o nível de PRA-ELISA e Grupo E (n=14): pacientes sensibilizados que diminuíram o nível de PRA-ELISA durante o primeiro ano pós-transplante. A incidência de rejeição aguda foi de 23,4%. Pacientes dos Grupos B, C e D apresentaram mais episódios de rejeição aguda (respectivamente, 57%; 60% e 100%) que os dos Grupos A (18%) e E (7%), (p<0,001). Rejeições ocorridas no Grupo A foram histologicamente menos severas do que as dos outros Grupos (p=0,03) e com menor incidência de C4d+ (p<0,001). Entre os pacientes com rejeição aguda, 44% deles apresentaram anticorpos no momento da rejeição, sendo que em 90% dos casos esses anticorpos foram doadorespecíficos. Rejeição mediada por células, ou seja, sem anticorpos e com C4d-, ocorreu em 56% dos casos. A incidência global de rejeição mediada por anticorpos (RMA) foi de 11%. A sobrevida do enxerto censurada para óbito foi menor em pacientes com rejeição aguda (p<0,001), especialmente naqueles com anticorpos anti-HLA doador-específicos (p<0,001), com C4d+ (p=0,003) e nos casos de RMA (p<0,003). CONCLUSÃO: Nossos dados sugerem que a monitorização dos anticorpos anti-HLA após o transplante renal pode ser útil no diagnóstico das respostas mediadas por anticorpos e tem implicações em termos de sobrevida do enxerto. / INTRODUCTION: The aim was to follow prospectively anti-HLA antibodies (Abs) after kidney transplantation and to evaluate their association with acute rejection episodes, C4d staining and graft survival. METHODS: We analyzed 926 sera from 111 transplanted patients until graft lost or during 1 year posttransplant. The antibodies were analyzed using Panel Reactive Antibodies by Enzyme Linked Immuno Sorbent Assay (PRA-ELISA). Donor-specific antibodies (DSA) were detected by crossmatch tests and characterized by single antigen beads. Acute rejections (AR) were classified by Banff 97 criteria, updated in 2003. RESULTS: According to post-transplant PRAELISA the patients were classified in 5 groups: Group A (n=80): no evidence of Abs pre and post-transplant; Group B (n=8): patients with Abs de novo; Group C (n=5): sensitized patients who sustained the same PRA-ELISA levels; Group D (n=4): sensitized patients who increased PRA-ELISA levels and Group E (n=14): sensitized patients who decreased PRA-ELISA levels during the first year. The overall incidence of acute rejection was 23,4%. Patients from Groups B, C and D had more AR (respectively, 57%; 60% and 100%) than patients from Groups A (18%) and E (7%), (p<0.001). Patients from Group A had lower Banff scores than other groups (p=0.03) and lower rates of C4d positivity on AR biopsies (p<0.001). Among patients with AR, 44% of them had antibodies which appeared/increased during the AR episodes, and 90% were DSA. AR were pure cell-mediated (C4d-/Abs-) in 56% of the cases. The overall incidence of antibody-mediated rejection (AMR) was 11%. One-year censored graft survival was lower in patients with AR (p<0.001), specially in those with DSA (p<0.001), C4d+ (p=0.003), and AMR (p<0.003). CONCLUSION: Our data suggest that monitoring of anti- HLA antibodies post-transplantation is an useful tool for the diagnosis of antibody-mediated responses, and has prognostic implications in terms of graft survival.
125

Identification d'Epitopes T CD4+ d'Antigènes tumoraux

Wang, Xiao-Fi 08 February 2007 (has links) (PDF)
L'induction d'une immunité efficace contre les tumeurs nécessite de recruter des lymphocytes T CD4+ auxiliaires et spécifiques. De ce fait, les peptides de tumeurs présentés par les molécules HLA II sont de potentiels candidats pour l'immunothérapie anticancéreuse. Le but de ce travail a été l'identification de nouveaux épitopes T CD4+ dérivés de trois antigènes différents : Trag-3 (Taxol Resistant Associated Gene) (un travail effectué en collaboration), un antigène spécifique des tumeurs ; la Survivine, un antigène surexprimé ; et l'ensemble de la famille MAGE-A, une famille d'antigènes spécifiques des tumeurs. Toutefois, l'utilisation d'épitopes peptidiques dans la vaccination nécessite de tenir compte du polymorphisme des molécules HLA afin de couvrir le maximum d'individus. Dans cette optique, nous avons appliqué deux stratégies différentes d'identification de peptides, à savoir : 1) identifier des peptides présentés par plusieurs molécules de HLA II (ces peptides sont appelés épitopes promiscuous). Cette stratégie a été appliquée à l'antigène Trag-3 et à la Survivine ; 2) identifier des peptides présentés par les molécules les plus représentées dans la population : les molécules HLA-DP4. Cette stratégie a été appliquée à la famille d'antigènes MAGE-A. Pour chercher les épitopes promiscuous, des peptides chevauchants couvrant l'intégralité de la séquence de Trag-3 et de la Survivine ont tous été synthétisés et testés pour leur capacité de liaison vis-à-vis de 12 molécules HLA-II (DR et DP). L'immunogénicité de peptides pouvant se lier avec plusieurs molécules de HLA II a été évaluée par la génération de lymphocytes T CD4+. Finalement, un peptide de Trag-3 (P34-48) et 4 peptides de la Survivine ont été mis en évidence. De plus, des réponses spontanée vis-à-vis du peptide Trag-3 34-48 ont été détectées dans les patients atteints de cancers. Pour chercher les épitopes restreints au HLA-DP4, nous avons d'abord établi un programme de prédiction de ligands potentiels de HLA-DP4. 9 gènes de la famille de MAGE-A ont été analysés et 12 peptides prédits ont été finalement synthétisés et testés dans les tests de liaison de HLA-DP4. 7 peptides ayant une meilleure activité avec les molécules de HLA-DP4 ont été sélectionnés pour évaluer leur immunigénicité in vitro. Finalement, 2 peptides de MAGE-A1 et un peptide de MAGE-A12 ont été mis en évidence qu'ils contiennent des épitopes naturellement présentés et apprêtés dans la présentation de l'antigène natif. En conclusion, tous les peptides identifiés dans ce travail présentent tous un intérêt pour la conception des vaccins peptidiques. Nous avons aussi proposé une méthode de prédiction de liaison de HLA-DP4 qui facilite significativement la sélection des peptides..
126

Die immunmodulatorische Wirkung von Ethylpyruvat

Hollenbach, Marcus 06 December 2011 (has links) (PDF)
In einer Vielzahl von Arbeiten konnten anti-inflammatorische Eigenschaften von Ethylpyruvat (EP) aufgezeigt werden. An verschiedenen Modellen der Sepsis, des hämorrhagischen Schocks, von Verbrennungsschäden, des Apoplex oder der Ischämie und Reperfusion wurde bei der Behandlung mit EP ein protektiver Effekt sowie eine verminderte Produktion von pro-inflammatorischen Zytokinen nachgewiesen. Als biochemische Grundlage wurde die Interaktion von EP mit dem Transkriptionsfaktor NF-κB identifiziert, die spezifischen Regulationsmechanismen konnten bisher allerdings nicht zufriedenstellend aufgeklärt werden. In dieser Arbeit wurde als eine neue mögliche Erklärung für die anti-inflammatorischen Eigenschaften des EP und weiterer α-oxo-Karbonsäureester die Inhibierung der Glyoxalase I (Glo-I) aufgezeigt. In vitro-Experimente zur Enzymaktivität belegten die Hemmung der Glo-I durch EP, während α-Hydroxy-Karbonsäureester wie L-Ethyllaktat (EL) keine inhibierenden Eigenschaften aufwiesen. Dennoch waren sowohl EP als auch EL und weitere Laktatester in der Lage, die LPS-induzierte Produktion von pro-inflammatorischen Zytokinen wie IL-1β, IL-6, IL-8 und TNF-α von humanen immunkompetenten Zellen zu supprimieren und die Expression von Immunrezeptoren wie HLA-DR, CD14 und CD91 zu modulieren. Somit konnten erstmals anti-inflammatorische Eigenschaften von Laktatestern nachgewiesen sowie eine Verbindung zwischen den Glyoxalase-Enzymen und dem Immunsystem etabliert werden. Diese und weitere Ergebnisse zur Einflussnahme der Karbonsäureester auf die Zellvitalität präsentieren das Glyoxalasesystem als mögliches Ziel neuer Therapiekonzepte für die Immunsuppression und bestätigen dessen Bedeutung für die Entwicklung von Anti-Tumor-Agenzien.
127

F811aAssociação dos genes KIR2DL2/KIR2DL3 e alelos HLA-C do grupo 1 com a mielopatia associada ao HTLV-1/paraparesia espástica tropical (HAM/TSP)

Fraga, Igor Ives Santos January 2014 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-07-23T16:56:03Z No. of bitstreams: 1 Igor Ives Santos Fraga Associação... 2014.pdf: 1141300 bytes, checksum: 79bef8840226ef6a639a9c8c9e118161 (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2015-07-23T16:56:29Z (GMT) No. of bitstreams: 1 Igor Ives Santos Fraga Associação... 2014.pdf: 1141300 bytes, checksum: 79bef8840226ef6a639a9c8c9e118161 (MD5) / Made available in DSpace on 2015-07-23T16:56:29Z (GMT). No. of bitstreams: 1 Igor Ives Santos Fraga Associação... 2014.pdf: 1141300 bytes, checksum: 79bef8840226ef6a639a9c8c9e118161 (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / O controle da carga proviral do HTLV-1 depende em parte da lise de células infectadas por células citotóxicas mediada pelos linfócitos T CD8⁺ e pelas células NK (Natural killer). A família de receptores KIR (killer-cell immunoglobulin-like receptor) interage com as moléculas de HLA de classe I, principalmente os alelos do HLA C do grupo 1 (C*01, C*03, C*07, C*08, C*12, C*13, C*14 e C*16), ativando ou inibindo a função destas células.O objetivo do presente estudo foi avaliar se os genes KIR2DL2/KIR2DL3 e os alelos de HLA-C do grupo 1 estão associados ao controle da carga proviral do HTLV-1 e ao diagnóstico de HAM/TSP. O estudo foi realizado no Centro de HTLV da Escola Bahiana de Medicina e Saúde Púbica, em Salvador-Bahia. A presença dos genes KIR2DL2 e KIR2DL3 foi determinada por PCR em tempo real (Syber Green). Foram incluídos 248 indivíduos infectados pelo HTLV-1 (161 assintomáticos e 87 com HAM/TSP) cujos alelos de HLA de classe I haviam sido previamente determinados. A carga proviral (quantificada por PCR em tempo real) e as frequências de indivíduos assintomáticos e com diagnóstico de HAM/TSP (Possível, Provável e Definido) foram comparadas de acordo com a presença ou ausência dos genes KIR avaliados. As frequências dos genes KIR2DL2 e KIR2DL3 foi 84,3% e 96,8%, respectivamente. Não foram observadas diferenças estatisticamente significantes na frequência de indivíduos que possuíam os genes (KIR2DL2 ou KIR2DL3) nos grupos clínicos, assim como na frequência de indivíduos que tinham simultaneamente os genes KIR e os alelos de HLA-C do grupo 1. Os indivíduos do grupo HAM/TSP possível que apresentavam o gene KIR2DL2 tinham menor carga proviral (2,9% de células infectadas) que os indivíduos sem este gene (19,2% de células infectadas) (p<0,001). Quando avaliamos a combinação da presença do gene KIR2DL2 com os alelos de HLA-C do grupo 1, menor carga proviral (2,1%) foi observada nos indivíduos que apresentavam algum dos alelos de HLA-C do grupo 1,comparados aqueles que portavam apenas KIR2DL2 (5,0%) (p=0,013). Menor carga proviral também foi observada nos indivíduos assintomáticos que portavam simultaneamente o gene KIR2DL2 e o alelo HLA-C*07, comparados aos indivíduos com apenas o gene KIR2DL2 (p=0,03), enquanto que os indivíduos com HAM/TSP-PB que tinham essa combinação (KIR2DL2/HLA-C*07) apresentaram tendência de menor carga proviral (p=0,051). Em conclusão, a presença da combinação do gene KIR2DL2 e de algum alelo de HLA-C do grupo 1 está associada ao controle da carga proviral. Este estudo quantificou pela primeira vez as frequências de genes KIR em uma coorte de indivíduos infectados pelo HTLV-1 do estado da Bahia. Estudos futuros são necessários para confirmar estes achados em outras populações e avaliar o valor prognóstico da associação de KIR2DL2 e HLA-C do grupo 1. / The control of proviral load of HTLV-1 depends in part of the lysis of infected cells mediated by cytotoxic CD8⁺T lymphocytes and NK (Natural killer) cells. The family of KIR (killer-cell immunoglobulin-like receptor) interacts with HLA class I molecules, especially those HLA-C alleles in-group 1 (C*01, C*03, C*07, C*08, C*12, C*13, C*14 and C*16) by activating or inhibiting the function of these cells. The aim of this study was to evaluate if the KIR2DL2, KIR2DL3 genes and group 1 HLA-C alleles are associated with the control of proviral load of HTLV-1 and the diagnosis of HAM/TSP. The study was performed at Bahiana School HTLV Center of Medicine and Health Public, in Salvador, Bahia. The presence of KIR2DL2 and KIR2DL3 genes was determined by real-time PCR (Syber Green). The study included 248 subjects infected with HTLV-1(161 and 87 asymptomatic with HAM/TSP) whose HLA class I alleles were previously determined. The proviral load (quantified by real-time PCR) and the frequency asymptomatic individuals diagnosed with HAM/TSP (possibly, probably and definitive) were compared according to the presence or absence of KIR genes evaluated. The frequencies of KIR2DL2 and KIR2DL3 genes were 84.3% and 96.8%, respectively. No statistically significant differences were observed in the frequency of individuals who possessed the genes (KIR2DL2 or KIR2DL3) in clinical groups, as well as the frequency of individuals who had both the KIR genes and HLA-C alleles group 1. Individuals in the group HAM/TSP possible to KIR2DL2 showed that the gene had lower proviral load (2.9%of cells infected) individuals without this gene (19.2% infected cells) (p<0.001). When we evaluated the combination of the presence of KIR2DL2 and 2DL3 genes with HLA-C genes in group 1, lower proviral load (2.1%) was observed in individuals with any of the alleles of HLA-C group 1, compared who those which harbored only KIR2DL2 (5.0%) (p=0.013) .Minor proviral load was also observed in asymptomatic individuals which carried both the KIR2DL2 gene and HLA-C*07 allele when compared to individuals with only KIR2DL2 gene (p=0.03), whereas patients with HAM/TSP-PB that had this combination (KIR2DL2/HLA-C*07) tended to lower proviral load(p=0.051). In conclusion, the presence of the combination of KIR2DL2 gene and a HLA-C group1allele is associated with proviral load control. This study quantified for the first time the frequencies of KIR genes in a cohort of individuals infected with HTLV-1 in Bahia. Future studies are needed to confirm these findings in other populations and to evaluate the prognostic value of KIR2DL2 association and HLA-C group 1.
128

Architecture de simulation distribuée temps-réel / Real-time distributed simulation architecture

Chaudron, Jean-Baptiste 25 January 2012 (has links)
Ce travail de thèse s'inscrit dans le projet plus global PRISE (Plate-forme de Recherche pour l'Ingénierie des Systèmes Embarqués) dont l'objectif principal est le développement d'une plateforme d'exécution pour les logiciels embarqués. De tels logiciels sont dits critiques et ils sont, par conséquent, soumis à des règles de conception spécifiques. Notamment, ces logiciels doivent répondre à des contraintes de temps réel et ainsi garantir des comportements temporels prédictifs afin de toujours donner des résultats justes avec le respect d'échéances temporelles.L'objectif de cette thèse est d'évaluer l'utilisation des techniques de la simulation distribuée (et particulièrement de la norme HLA) pour répondre aux besoins de simulation hybride et temps réel de la plate-forme. Afin de respecter ces contraintes et garantir la prédictibilité temporelle d'une simulation distribuée, il faut avoir une vision complète de l'ensemble du problème et notamment des différents niveaux d'actions : applicatif, intergiciel, logiciel, matériel et aussi formel pour la validation du comportement temporel.Cette thèse se base sur la RTI (Run Time Infrastructure, intergiciel HLA) de l'ONERA : le CERTI et propose une démarche méthodologique adaptée à ces différents niveaux d'actions. Des cas d'étude, notamment un simulateur du vol d'un avion, ont été spécifiés, implémentés et expérimentés sur la plate-forme PRISE. / This work takes place in the global project PRISE (Plate-forme de Recherche pour l'Ingénierie des Systèmes Embarqués) in which the focus is to develop an execution platform for embedded software. Embedded software are said criticals and, therefore, are subject to specific design rules.Particularly, these software must meet real time constraints and thus ensure a temporal predictive behaviour in order to always give accurate results with respect to corresponding timing deadlines.The main objective of this thesis is to study the use of distributed simulation techniques (and specifically the HLA standard) to meet the real-time and hybrid simulation needs of the PRISE platform. To comply with these real-time constraints and ensure the predictability of a distributed simulation, we must have a complete view of the whole problem and in particular the different levels of action: application, middleware, software, hardware and also a formal level for validation of the timing behaviour.This work is based on the RTI (Run Time Infrastructure, HLA middleware) from ONERA laboratory called : the CERTI and proposes a methodological approach adapted to take into account these different levels of action. Some case studies, including a flight simulator of an aircraft, have been specified, implemented and tested on the PRISE platform.
129

Estudo de polimorfismos dos genes KIR e HLA em sangue de cordão umbilical e placentário de recém-nascidos a termo e pré-termo

Marquezotti, Fernanda January 2014 (has links)
Background. O nascimento pré-termo permanece sendo grande causa de mortalidade neonatal. A vulnerabilidade dos prematuros se dá principalmente pelas freqüentes intervenções médicas e por sua imaturidade imunológica. As infecções neonatais aumentam a probabilidade de complicações e prolongam o tempo de internação, aumentando o risco de mortalidade. A atividade das células Natural Killer (NK) em recém-nascidos prematuros está reduzida e associada com maior susceptibilidade a agentes infecciosos. As células NK são capazes de mediar a resposta do sistema imune inato contra células infectadas por vírus e células malignas transformadas, podendo provocar um ataque direto às células alvo. Os principais receptores das células NK são os KIR ou killer immunoglobulin-likereceptors que reconhecem moléculas de HLA classe I. Objetivo. Investigar o polimorfismo dos genes KIR e HLA de classe I nos recémnascidos pré-termos de muito baixo peso em comparação com recém-nascidos a termo. Métodos. Foram genotipados 154 recém-nascidos, 60 pré-termo e 94 a termo, para 16 genes KIR e seus ligantes HLA pelos métodos PCR SSO e PCR SSP, respectivamente. Resultados. Há diferença estatísticamente significativa (P<0.0001) entre recémnascidos pré-termo e a termo para o gene KIR2DS4, sendo menos freqüente no grupo de recém-nascidos pré-termos. Conclusões. A menor frequência do KIR2DS4 evidencia uma imunidade natural deficiente nesse grupo de recém-nascidos prematuros. / Background. Preterm birth remains a major a cause of neonatal mortality. Preterm infants are particularly vulnerable because of frequent medical intervention and an immature immune system. Neonatal infections increase the likelihood of complications and prolong hospital stay, increasing the risk of mortality. The activity of natural killer (NK) cells is reduced in preterm neonates and associated with increased susceptibility to infectious agents. NK cells are capable of mediating the innate immune response to virally infected cells and malignantly transformed cells, which might lead to a direct attack on target cells. Killer-cell immunoglobulin-like receptors (KIR) are the main NK cell receptors, and are known to recognize Human Leukocyte Antigen (HLA) class I molecules. Objective. To investigate polymorphisms of KIR and HLA class I genes in very low birth weight preterm neonates compared with full-term neonates. Methods. 154 neonates, 60 preterm and 94 full-term, were genotyped for 16 KIR genes and their HLA ligands by PCR-SSO and PCR-SSP respectively. Results. There was a statistically significant difference (P<0.0001) between preterm and full-term neonates for the KIR2DS4 gene, which was less frequent in preterm neonates. Conclusions. The lower frequency of KIR2DS4 indicates a deficient innate immune response in the group of preterm neonates.
130

Alorreatividade dos enxertos ósseos homólogos na reconstrução alveolar em humanos / Allorreactivity of fresh-frozen boné graft in human ridge augmentation

Mayara Perez Braga 17 February 2014 (has links)
Enxerto ósseo homólogo é utilizado independentemente da compatibilidade HLA entre doador e receptor ou uso de drogas imunossupressoras. Considerando o volume de transplantes ósseos realizados no Brasil e o possível efeito deletério da sensibilização HLA para o transplante de órgãos sólidos, este estudo tem como objetivo avaliar a alorreatividade do enxerto ósseo homólogo fresco-congelado utilizado na reconstrução alveolar com finalidade de reabilitação oral com prótese sobre implantes. Anticorpos anti-HLA e anti-MICA foram monitorados através do teste Labscreen Mixed, nos intervalos 0, 7, 30, 90 e 180 pós transplante ósseo em 15 pacientes (6 homens e 9 mulheres, idade média 58,1, DP=10,1) que estavam em tratamento no Instituto de Odontologia da Pontifícia Universidade Católica do Rio de Janeiro. Caso resultado do teste Mixed fosse positivo (Razão de fundo normatizado, NBG>4,5) o teste Labscreen Single (tecnologia antígeno único por pérola, SABA) era realizado para verificar se os anticorpos anti-HLA eram específicos ao doador. Nenhum paciente relatou transplante prévio, 4 relataram transfusão prévia e todas as mulheres relataram gravidez. Dez pacientes não apresentaram reação positiva no dia 0 sendo considerados não sensibilizados previamente (NSP); destes, 6 pacientes permaneceram sem nenhuma evidência de sensibilização, 2 pacientes apresentaram reação positiva para Classe I e II; 2 para Classe I apenas; e 2 para MICA, sendo considerados sensibilizados pelo enxerto ósseo oral. Dois pacientes apresentaram aumento de Intensidade Média de Fluorescência (&#916;MFI>1000) de anticorpos específicos ao doador para Classe I e Classe II, e 2 somente para Classe II, demonstrando uma reação específica ao doador. Os resultados sugerem uma alorreatividade HLA oscilatória ao enxerto ósseo homólogo em reconstruções alveolares, confirmada pela formação de anticorpos anti-HLA específicos ao doador em 4 pacientes (27%) da amostra. / Bone allografts are used without HLA donor-receptor compatibility or imunosupressor therapy. Taking in consideration the amount of bone graft procedures performed in Brazil and the possible deleterious effect of HLA sensitization in solid organ transplantation, the aim of this study was to evaluate fresh-freeze bone graft alorreactivity used in ridge augmentation surgery before oral rehabilitation with implants supported bridges. Anti-HLA and anti-MICA antibodies were evaluated by Labscreen Mixed test, at 0, 7, 30, 90 e 180 days after bone transplantation in 15 patients (6 men e 9 women, mean age 58,1, SD=10,1) treated at the Dental Institute of the Rio de Janeiro Catholic University. If the mixed test (Normalized Background Ratio, NBG>4,5) was positive, donor specificity was evaluated by Labscreen Single test (Single Antigen Bead Assay technology, SABA). None of patients had previous transplant history, 4 had transfusion history, and all women had pregnancy history. Ten patients did not have positive results at baseline and were considered not sensitized previously; 6 patients of them did not have any sensitization evidence during 6 month follow up, 2 patients had positive reaction for anti-HLA Class I and II; 2 were positive for anti-HLA Class I only; e 2 patients were positive for anti-MICA, and were considered sensitized by oral bone graft. Two patients had increased values of Median Fluorescence Intensity (&#916;MFI>1000) of anti-HLA donor specific antibodies Class I and II, 2 for Class II only, showing a donor specific alorreactivity. The results sugest an oscilatory HLA reactivity, confirmed by the donor specific antibodies formation on 4 patients (27%) of this study.

Page generated in 0.0568 seconds