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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.
31

Lymphocytes T et vieillissement : lymphopénie ou redistribution ? / Lymphocytes T and Ageing : Lymphopenia or Redistribution ?

Martinet, Kim 23 September 2014 (has links)
L’atteinte de l’âge sur les populations lymphocytaires T conventionnelles CD4 et CD8 avec l’avancée en âge est relativement bien décrite en périphérie lymphoïde secondaire chez la souris, et dans le sang périphérique chez l’homme. Deux paramètres sont observés : réduction du nombre de ces cellules et altération du ratio naïve/mémoire. À l’inverse, l’évaluation des tissus lymphoïdes tertiaires et des tissus extra lymphoïdes dans les réponses immunes, reste à affiner. Notre étude au cours du vieillissement physiologique du compartiment T fut menée dans des tissus lymphoïdes et non lymphoïdes de souris C57BL/6 wild-type, âgées entre 2 et 6 mois, entre 10 et 14 mois et entre 22 et 26 mois. Nous avons démontré que la lymphopénie T classiquement décrite liée au vieillissement dans les organes lymphoïdes secondaires ne s’applique pas à tout l’organisme : les compartiments intestinaux étudiés présentent une accumulation de cellules TCRαβ+ CD4+ (TCD4) et CD8+ (TCD8). Nos résultats dévoilent un impact différentiel du vieillissement sur le nombre absolu des différents compartiments cellulaires TCRαβ+ dans les organes lymphoïdes et la muqueuse intestinale. Ces résultats suggèrent donc que la lymphopénie T décrite dans les organes lymphoïdes s’établissant au cours du vieillissement pourrait être essentiellement liée à une redistribution des lymphocytes. A l’inverse, la persistance des cellules T régulatrices dans les organes lymphoïdes secondaires pourrait être liée à une production locale dans la muqueuse intestinale. Il semble donc que l’équilibre TCD8/TCD4 peut être différemment affecté selon le site considéré et cette observation peut fournir une justification pour la plus grande susceptibilité aux infections observée avec l’âge. / Consequences of ageing on conventional CD4 and CD8 T lymphocytes populations is relatively well described in murine secondary lymphoid organs and in human peripheral blood: reduction the number of these cells and alteration of naïve/effector-memory ratio in favour of effector-memory cells. Conversely, evaluation in tertiary lymphoid tissues and non-lymphoid tissues remains to be refined. We conducted an exhaustive analysis of T cell compartments during physiological aging in lymphoid and non-lymphoid tissues isolated from wild-type C57BL/6 mice aged of 2 to 6 months, 10 to 14 months and 22 to 26 months. We demonstrated that T lymphopenia described classically associated with aging in the secondary lymphoid organs does not apply to the whole organism: intestinal compartments studied show an accumulation of TCRαβ+ CD4+ cells (TCD4) and CD8+ (TCD8). Our results reveal a differential impact of aging on the absolute number of different TCRαβ+ cellular compartments in lymphoid organs and intestinal mucosa. T cell lymphopenia in secondary lymphoid organs currently associated to ageing may essentially reflect T cell redistribution. TCD8/TCD4 balance may be affected differently depending on the site considered and this observation may provide a rationale for the greater susceptibility to infection observed with age.
32

Modulation intestinaler Wundheilungsvorgänge und Erhaltung der mukosalen Immunhomöostase

Sturm, Andreas 04 August 2004 (has links)
Die intestinale Mukosa bildet eine biologisch wichtige Barriere zwischen dem Organismus und den schädigenden Faktoren im intestinalen Lumen. Diese komplexe Aufgabe wird durch eine hochdifferenzierte intestinale Mukosa bewältigt, die eine strukturelle sowie funktionelle intestinale Barriere bildet. Das Ziel der vorliegenden Arbeiten war, ausgewählte Aspekte der Regulations- und Reparaturmechanismen der intestinalen mukosalen Barriere weitergehend zu charakterisieren. Unsere Untersuchungen zeigen, dass das Phospholipid Lysophosphatidsäure (LPA) die intestinale epitheliale Zellmigration stimuliert, die dieser Zellen jedoch inhibiert. Die Modulation der intestinalen Wundheilung durch LPA erfolgt durch einen TGF-b-unabhängigen Mechanismus und wird über einen G-Protein-abhängigen Rezeptor vermittelt, wie wir im Rahmen umfangreicher Untersuchungen zur Signaltransduktion unter Verwendung spezifischer Modulatoren der Signaltransduktion wie Bradykinin, Phorbolester, Pertussistoxin, Suramin und neutralisierender TGF-b-Antikörper belegen konnten. In weiteren Experimenten konnten wir zeigen, dass LPA auch in-vivo einen wundheilungsfördernden Effekt besitzt. Die topische Applikation von LPA in diesem experimentellen Kolitismodell bewirkte einen geringeren Gewichtsverlust sowie ein geringeres Ausmaß an intestinaler Entzündung und Nekrose in-vivo. Diese Untersuchungen legen somit nahe, dass LPA die intestinale epitheliale Wundheilung durch eine Modulation der intestinalen epithelialen Migration und Proliferation durch TGF-b-unabhängige Mechanismen stimuliert. Weitere Untersuchungen beschäftigten sich mit der funktionellen Charakterisierung von Lamina propria T-Zellen (LPT) und peripheren Blut T-Zellen (PBT). Wir konnten zeigen, dass der Zellzyklus von LPT distinkt von PBT reguliert wird. Hierbei spielt der Zellzyklusinhibitor p53 eine zentrale Rolle in der Zellzyklusregulation von LPT. Um Autoimmunität zu verhindern, muss es nach einer Eliminierung des Antigens wieder zu einer Depletion des Pools an Effektor-T-Zellen durch die Aktivierung der Apoptose kommen. Wir konnten zeigen, dass beim Antigen-induzierten Zelltod von LPT der intrinsische Apoptoseweg aktiviert wird und Caspase-8 hierbei eine zentrale Rolle spielt. Physiologischerweise sind Zellzyklus und Apoptose eng miteinander verbunden. In weiteren Versuchen konnten wir jedoch zeigen, dass dies nicht bei LPT der Fall ist und somit die von PBT distinkte Regulation von Zellzyklus und Apoptose mukosaler T-Zellen weiter unterstreichen. Zusammengefasst konnten wir durch ausgewählte Untersuchungen zeigen, dass die intestinale Barriere und ihre funktionelle Beeinflussung eine wesentliche Rolle in der Pathogenese und Therapie intestinaler Entzündungen besitzt. Eine Beeinflussung intestinaler Reparaturprozesse und Modulation abnormer T-Zellen könnte neue Möglichkeiten in der Therapie intestinaler Entzündungen, wie z.B. chronisch entzündlichen Darmerkrankungen bewirken. / The intestinal mucosa protect the host from the potential harmful content of the intestinal lumen. To accomplish this difficult goal, the highly complex mucosa forms an anatomical as well as functional barrier to protect the organism.In this work, we aimed to characterize distinct aspect of the intestinal barrier, focussing on distinct regulation and repair mechanism of the intestinal mucosa. First, we demonstrate, that the phospholipid lysophosphatidic acid (LPA) stimulate the migration of intestinal epithelial cells, but, in contrast, inhibit their proliferation. This effect is mediated by G-protein receptors and is TGF-b-independent, as we could demonstrate in further experiments using bradykinine, phorbole ester, pertussis toxin and suramine to modulate distinct signalling pathways.We then demonstrated, using a well-established animal model of colitis, that LPA enhances intestinal wound healing in-vivo. In detail, the topical application of LPA in TNBS-treated rats reduced weight loss, ameliorate intestinal inflammation and prevented necrosis in the animals. This experiments demonstrate for the first time, that LPA modulates migration and proliferation of intestinal epithelial cells by distinct TGF-b independent pathways. Further experiments aimed to explore functional differences between peripheral blood (PBT) and mucosal T-cells (LPT). We demonstrated, that the cell cycle is distinctively regulated in PBT and LPT, identifying p53 as key regulator of LPT cell cycling. To avoid auto-immunity, the pool of effector T-cells must be depleted by apoptosis, once the antigen has been cleared. We demonstrate, that intrinsic pathway of apoptosis is activated during the antigen-induced cell death in LPT and that caspase-8 activity is required to execute LPT apoptosis. Cell cycle and apoptosis are ultimately linked. However, as we show in further experiments, this is not the case in LPT, underlining the distinct regulation of LPT cell cycle and apoptosis.In conclusion, using various distinct experimental tools, we demonstrate that the intestinal barrier itself and the modulation its function plays a fundamental role in the pathogenesis mucosal inflammation. The data presented in this work may therefore open new therapeutic options in the therapy of intestinal inflammatory disorders, such as inflammatory bowel diseases.
33

Direito de imagem e direito de arena no contrato de trabalho do atleta profissional

Soares, Jorge Miguel Acosta 01 June 2007 (has links)
Made available in DSpace on 2016-04-26T20:25:33Z (GMT). No. of bitstreams: 1 Jorge Miguel Acosta.pdf: 862687 bytes, checksum: ba22994c6281f9b466309a86b18a963e (MD5) Previous issue date: 2007-06-01 / The purpose of this study was to deepen the current knowledge about employment contracts of football players or professional athletes. With the experience gained in the Union, a reflection was sought about four aspects of those contracts which permitted, after data systematization and exploration, a description, the definition of limits and consequently an in-depth analysis of the matter under study. Those aspects were: the historical evolution of this profession and of its legislation, the various views of the doctrine about the legal nature of such contracts, the Image Right and the Arena Right. A research about the historical evolution of the employment contract of this kind of athlete pointed out that the specific legislation for this category advanced very slowly. An analysis of the historical process revealed that the social gains obtained by the workers with the restatement of the labor laws early in the 40s only started to be enjoyed by football players half a century later, suggesting that the problems experienced by those athletes have their roots in the past history of that category. In parallel to the legislative history, the various formulations produced by the legal doctrine about the athlete and the athlete's contract with a club were also studied. Further, a brief description of the various conceptions of the doctrine makers about the legal nature of such contracts is also given. Then the issues relating to the Image Right are discussed, seeking an understanding of its insertion in the realm of the Personality Rights, as well as its new positioning as given by the 1988 Federal Constitution. The Maximum Law ascribed neverseen- before guarantees to those rights, an innovation even in relation to the most modern constitutions worldwide. The new constitutional approach to the Image Right has raised significant issues for the athlete category. The treatment now given to it has imposed a new reality to the clubs, forcing them to review old practices involving image assignment contracts, usually when signing up the athlete. Lastly, a study is conducted about the Arena Right, a figure created in Brazil with no similar elsewhere, and which is a relevant source of revenues for clubs and equivocally confounded with the Image Right. This study shows that those two rights are getting apart diametrally; they are different rights, with different title holders and diverse legal nature, although, mostly, they are considered as equivalent / O presente estudo procurou aprofundar o conhecimento que se tem sobre o contrato de trabalho dos jogadores de futebol, ou atletas profissionais. A partir da experiência acumulada junto a seu Sindicato, buscou-se uma reflexão sobre quatro aspectos desses contratos, que permitiram, após a sistematização e exploração dos dados, a descrição, a definição de limites e o conseqüente aprofundamento do objeto investigado. São eles: a evolução histórica da profissão e da legislação a ela referente, as diversas visões da doutrina acerca da natureza jurídica desse contrato, o Direito de Imagem e o Direito de Arena. A pesquisa sobre a evolução histórica do contrato de trabalho desse tipo de atleta identificou que o desenvolvimento da legislação específica para a categoria sempre foi muito lento. A análise do processo histórico revelou que as conquistas sociais obtidas pelo conjunto dos trabalhadores, com a CLT, no início dos anos de 1940, somente chegou aos jogadores de futebol quase meio século depois, sugerindo que os problemas vividos pelos atletas têm raízes no passado da categoria. Paralelamente à história legislativa, foram estudadas as diversas formulações produzidas pela doutrina jurídica sobre o atleta e seu contrato com os clubes. Também se expôs, de maneira sintética, as diversas concepções dos doutrinadores sobre a natureza jurídica desse contrato. Em seguida, foram estudadas as questões que envolvem o Direito de Imagem, buscando entender sua inserção no conjunto dos Direitos da Personalidade, assim como seu novo enquadramento dado pela Constituição Federal de 1988. A Lei Máxima passou a dar a esses direitos garantias nunca antes conhecidas, inovando mesmo perante as modernas constituições do mundo. O novo enfoque constitucional ao Direito de Imagem trouxe questões significativas para a categoria dos atletas. O tratamento agora dado a esse direito impôs nova realidade aos clubes, obrigando-os a uma revisão de antigas práticas envolvendo os contratos de cessão de imagem, usuais no momento da contratação do atleta. Por último, um estudo sobre o Direito de Arena, instituto de criação genuinamente nacional, sem paralelo no mundo, importante fonte de receita dos clubes, equivocadamente confundido com o Direito de Imagem. O estudo mostrou que os dois direitos distanciam-se diametralmente; são direitos diferentes, com distintos titulares e diversa natureza jurídica, apesar de, muitas vezes, serem tomados como equivalentes
34

IL-23 receptor and IL-12 receptor expression is restricted to distinct cell types in the IL-23R-GFP reporter mouse

Bellemare, Lisa 02 1900 (has links)
Les maladies inflammatoires de l'intestin (MII) sont caractérisées par des réponses immunitaires incontrôlées dans l'intestin. Des études génétiques ont associé un polymorphisme dans le gène de l'IL23R à la résistance aux MII. IL23R code pour la protéine de l’IL-23r, une sous-unité du récepteur à l’IL-23 (IL-23R). Ce récepteur appartient à la famille de l’IL-12R, contenant plusieurs récepteurs hétérodimériques. D’ailleurs, IL-12R et IL-23R partagent la sous-unité IL12Rb1. Néanmoins, ces deux récepteurs favorisent des réponses immunitaires distinctes (Th1 vs Th17). Ce mémoire caractérise les dynamiques d’expression cellulaires de l’IL-23R et l’IL-12R, afin d’élucider leurs rôles dans l’inflammation. Nous avons établi qu’IL-23R et IL-12R ne sont jamais co-exprimés, malgré qu’ils partagent la sous-unité IL-12Rβ1. Parmi les cellules de rates de souris, la protéine IL-23r est trouvée dans certaines cellules T TCRγδ ou T CD4+, quelques cellules B et des cellules Lti-like. La protéine IL-12Rβ2 est exprimée par quelques cellules B. L’analyse de l’expression de l’IL-23R et l’IL-12R dans différents organes révéla que la plus grande proportion de cellules exprimant l’IL-23R se retrouve dans la lamina propria de l'intestin grêle, alors que les cellules exprimant l’IL-12Rβ2 ont été retrouvées en proportion équivalente dans tous les organes lymphoïdes. Ces observations appuient les études génétiques suggérant un rôle prédominant de l’IL23R dans les intestins. Finalement, des cultures in vitro suggèrent que l’IL-23R ou l’IL-12R avaient des réactions croisées à l’IL-12 ou l’IL-23. L’étude de l’IL-23R dans les MII devrait donc être complémentée par l’étude de l’IL-12R, car les deux récepteurs pourraient avoir des rôles complémentaires. / Inflammatory bowel diseases (IBD) are characterised by uncontrolled immune responses in the gut. Genome-wide association studies (GWAS) have identified a protective polymorphism for IBD in the IL23R gene. IL23R codes for the IL-23r protein, one of the two subunits of IL-23R. IL-23R belongs to the IL-12R family, which contains many heterodimeric receptors. For example, both IL-12R and IL-23R share the IL-12Rβ1 subunit. Nevertheless, IL-12R and IL-23R are associated with different immune processes (Th1 vs. Th17). This thesis characterizes the cellular patterns of expression of both IL-23R and IL-12R, to further elucidate their roles in inflammation. We established that IL-23R and IL-12R were never co-expressed together, even though they share the IL-12Rβ2 subunit. Analysis of murine splenocytes revealed that IL-23R is expressed by some TCRγδ T-cells, a few B-cells, CD4+ T-cells and several Lti-like cells. IL-12R protein was found in a few B-cells. The analysis of IL-23R and IL-12R expression in different organs revealed that the lamina propria of the small intestine was the organ containing the largest proportion of IL-23r+ cells. IL-12R+ cells were found in constant numbers throughout the organs. Finally, in vitro cultures showed that IL-23R and IL-12R had crossed reaction to IL-12 and IL-23. Study of IL-23R in IBD should always be accompanied by IL-12R analysis, because both receptors could have complementary roles.
35

Metaforičnost partnerských pojmenování / Metaphors in Partners' Calling

Štěpánová, Pavla January 2013 (has links)
Diploma thesis Figurativeness of denominations in a partnership based on a questionnare survey deals with a discourse of figurative denominations in partnerhips. Firstly, the position of partnership denominations within the field of onomastics is defined and a general language characteristics of these denomations is presented. Further on, the main ideas from cognitive linguistics are presented, especially the conceptual metaphor theory which has been the basis for an analysis and interpretation of partnership denominations. These have been divided into several semantical groups in the context of which the partnership denominations are being analysed.
36

IL-23 receptor and IL-12 receptor expression is restricted to distinct cell types in the IL-23R-GFP reporter mouse

Bellemare, Lisa 02 1900 (has links)
Les maladies inflammatoires de l'intestin (MII) sont caractérisées par des réponses immunitaires incontrôlées dans l'intestin. Des études génétiques ont associé un polymorphisme dans le gène de l'IL23R à la résistance aux MII. IL23R code pour la protéine de l’IL-23r, une sous-unité du récepteur à l’IL-23 (IL-23R). Ce récepteur appartient à la famille de l’IL-12R, contenant plusieurs récepteurs hétérodimériques. D’ailleurs, IL-12R et IL-23R partagent la sous-unité IL12Rb1. Néanmoins, ces deux récepteurs favorisent des réponses immunitaires distinctes (Th1 vs Th17). Ce mémoire caractérise les dynamiques d’expression cellulaires de l’IL-23R et l’IL-12R, afin d’élucider leurs rôles dans l’inflammation. Nous avons établi qu’IL-23R et IL-12R ne sont jamais co-exprimés, malgré qu’ils partagent la sous-unité IL-12Rβ1. Parmi les cellules de rates de souris, la protéine IL-23r est trouvée dans certaines cellules T TCRγδ ou T CD4+, quelques cellules B et des cellules Lti-like. La protéine IL-12Rβ2 est exprimée par quelques cellules B. L’analyse de l’expression de l’IL-23R et l’IL-12R dans différents organes révéla que la plus grande proportion de cellules exprimant l’IL-23R se retrouve dans la lamina propria de l'intestin grêle, alors que les cellules exprimant l’IL-12Rβ2 ont été retrouvées en proportion équivalente dans tous les organes lymphoïdes. Ces observations appuient les études génétiques suggérant un rôle prédominant de l’IL23R dans les intestins. Finalement, des cultures in vitro suggèrent que l’IL-23R ou l’IL-12R avaient des réactions croisées à l’IL-12 ou l’IL-23. L’étude de l’IL-23R dans les MII devrait donc être complémentée par l’étude de l’IL-12R, car les deux récepteurs pourraient avoir des rôles complémentaires. / Inflammatory bowel diseases (IBD) are characterised by uncontrolled immune responses in the gut. Genome-wide association studies (GWAS) have identified a protective polymorphism for IBD in the IL23R gene. IL23R codes for the IL-23r protein, one of the two subunits of IL-23R. IL-23R belongs to the IL-12R family, which contains many heterodimeric receptors. For example, both IL-12R and IL-23R share the IL-12Rβ1 subunit. Nevertheless, IL-12R and IL-23R are associated with different immune processes (Th1 vs. Th17). This thesis characterizes the cellular patterns of expression of both IL-23R and IL-12R, to further elucidate their roles in inflammation. We established that IL-23R and IL-12R were never co-expressed together, even though they share the IL-12Rβ2 subunit. Analysis of murine splenocytes revealed that IL-23R is expressed by some TCRγδ T-cells, a few B-cells, CD4+ T-cells and several Lti-like cells. IL-12R protein was found in a few B-cells. The analysis of IL-23R and IL-12R expression in different organs revealed that the lamina propria of the small intestine was the organ containing the largest proportion of IL-23r+ cells. IL-12R+ cells were found in constant numbers throughout the organs. Finally, in vitro cultures showed that IL-23R and IL-12R had crossed reaction to IL-12 and IL-23. Study of IL-23R in IBD should always be accompanied by IL-12R analysis, because both receptors could have complementary roles.

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