Dissertations / Theses: 'Espace de Cantor'

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Ghawadrah, Ghadeer. "Théorie descriptive des ensembles et espaces de Banach." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066078/document.

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Cette thèse traite de la théorie descriptive des ensembles et de la géométrie des espaces de Banach. La première partie consiste en l’étude de la complexité descriptive de la famille des espaces de Banach avec la propriété d’approximation bornée, respectivement la propriété π, dans l’ensemble des sous-espaces fermés de C(Δ), où Δ est l’ensemble de Cantor. Ces familles sont boréliennes. En outre, nous montrons que si alpha This thesis deals with the descriptive set theory and the geometry of Banach spaces.The first chapter consists of the study of the descriptive complexity of the set of Banachspaces with the Bounded Approximation Property, respectively π-property, in the set ofall closed subspaces of C(∆), where ∆ is the Cantor set. We show that these sets areBorel. In addition, we show that if α<ω_1, the set of spaces with Szlenk index at most α which have a shrinking FDD is Borel. We show in the second chapter that the numberof isomorphism classes of complemented subspaces of the reflexive Orlicz function space L^Φ [0,1] is uncountable, where L^Φ [0,1]is not isomorphic to L^2 [0,1]

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Robert, Simon. "Une approche par les groupes amples pour l’équivalence orbitale des actions minimales de Z sur l’espace de Cantor." Electronic Thesis or Diss., Lyon 1, 2023. http://www.theses.fr/2023LYO10142.

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Cette thèse s'inscrit dans le cadre de la dynamique topologique, branche des systèmes dynamiques s'intéressant aux comportements qualitatifs asymptotiques de transformations continues provenant d'une action de groupe ou de semigroupe sur un espace métrique usuellement compact. Par exemple, une question classique pourrait être de savoir si tel système dynamique admet des points récurrents, c'est à dire des points qui vont revenir arbitrairement proche de leur point de départ infiniment souvent sous la dynamique. Souvent, de par leur caractère qualitatif et asymptotique, ces propriétés ne dépendent pas précisément du système mais plutôt des orbites des points, i.e des positions qu'il vont atteindre. D'où la notion d'équivalence orbitale au coeur de cette thèse, qui consiste à considérer que, après identification des espaces sous-jacents, deux systèmes dont tous les points auraient les mêmes orbites seraient "qualitativement les mêmes". Au cours des années 90, Giordano Putnam et Skau ont réussi à établir grâce à des outils d'algèbre homologique une classification à équivalence orbitale près des systèmes dynamiques minimaux provenant d'actions de \Z sur l'espace de Cantor en termes à la fois de groupes pleins et de mesures invariantes. Ce résultat montre en particulier qu'il existe une infinité non-dénombrable de tels systèmes différents à équivalence orbitale près, ce qui contraste assez fortement avec le cadre de la théorie ergodique, domaine très proche s'intéressant aux systèmes dynamiques mesurés, dans lequel la combinaison de deux célèbres résultats, l'un dû à Ornstein et Weiss et l'autre à Dye montre qu'il n'y a à équivalence orbitale près qu'une seule action de groupe moyennable sur un espace de probabilité standard. Ma principale contribution à travers le présent manuscrit consiste à apporter un éclairage et des preuves dynamiques élémentaires aux classifications obtenues par Giordano, Putnam et Skau (celle sur l'équivalence orbitale susmentionnée ainsi qu'une autre traitant d'une variation nommée équivalence orbitale forte), tant afin de les comprendre sous une autre perspective que pour tenter de les étendre à d'autres contextes. Chemin faisant, je démontrerai également un résultat de complexité Borélienne, à savoir que la relation d'isomorphisme de groupes dénombrables, localement finis et simples et une relation universelle provenant d'une action Borélienne de S_\infty, et nous améliorerons un résultat de Krieger sur la conjugaison des groupes amples This thesis takes place in the context of topological dynamics, a branch of dynamical systems concerned with the asymptotic qualitative behavior of continuous transformations arising from a group or semigroup action on a usually compact metric space. For example, a classic question might be whether a dynamical system admits recurrent points, i.e. points that will return arbitrarily close to their starting point infinitely often under the dynamics. Often, because of their qualitative and asymptotic nature, these properties do not depend precisely on the system but rather on the orbits of the points, i.e. the positions they will reach. Hence the notion of orbit equivalence at the heart of this thesis, which consists in considering that, after identification of the underlying spaces, two systems whose points all have the same orbits would be "qualitatively the same". In the 1990s, Giordano Putnam and Skau used homological algebra to establish a classification up to orbit equivalence of minimal dynamical systems arising from Z-actions on a Cantor space in terms of both full groups and invariant measures. This result shows in particular that there are non-countably many such different systems up to orbit equivalence, which contrasts quite strongly with the framework of ergodic theory, a very close field concerned with measured dynamical systems, in which the combination of two famous results, one due to Ornstein and Weiss and the other to Dye, shows that there is only one amenable group action on a standard probability space up to orbit equivalence. My main contribution in the present manuscript is to bring an elementary perpective and dynamical proofs to the classifications obtained by Giordano, Putnam and Skau (the one on orbital equivalence mentioned above as well as another one dealing with a variation called strong orbital equivalence), both in order to understand them from another perspective and to try to extend them to other contexts. Along the way, I will also prove a result of Borelian complexity, namely that the isomorphism relation of countable, locally finite and simple groups and a universal relation arising from a Borelian action of S_\infty, and improve a result of Krieger about the conjugation of ample groups

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Le, Manach Florian. "Sur l’approximation et la complétude des translatés dans les espaces de fonctions." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0237/document.

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Nous nous intéressons à l'étude de la cyclicité et la bicyclicité dans les espaces $ell^p(Z)$ à poids et à l'étude de la cyclicité dans les espaces de Dirichlet. Alors que Wiener a caractérisé la bicyclicité des vecteurs de $ell^1(Z)$ et $ell^2(Z)$ grâce à l'ensemble des zéros de la transformée de Fourier, Lev et Olevski ont démontré que cet ensemble ne peut caractériser la bicyclicité dans $ell^p(Z)$ lorsque $1 We are interested in the study of cyclicity and bicyclicity in weighted $ell^p(Z)$ spaces and the study of cyclicity in Dirichlet spaces. While Wiener characterized the bicyclicity in $ell^1(Z)$ and $ell^2(Z)$, thanks to the zero set of the Fourier transform, Lev and Olevski have shown that this set cannot characterize bicyclicity in $ell^p(Z)$ when $1 < p < 2$ for sequences in $ell^1(Z)$. Also Beurling, Salem and Newman were interested in the bicyclicity in $ell^p(Z)$ when $1 < p < 2$. In this work, we first extend the results of Beurling, Salem and Newman to the weighted $ell^p(Z)$ spaces, by studying the Hausdorff dimension and the capacity of the zero set of the Fourier transform. Then we prove that the Lev-Olevskii result remains valid for cyclicity in $ell^p(Z)$, $1 < p < 2$. In addition, we give sufficient conditions for the cyclicity in the weighted $ell^p(Z)$ spaces. Finally, we prove that, for a function $f$ in the disk algebra and in a generalized Dirichlet space, if $f$ is outer and the zero set of $f$ is reduced to a point then $f$ is cyclic. This generalizes the result of Hedenmalm and Shields who have treated the case of the classical Dirichlet space

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Milliet, Cédric. "Propriétés algébriques des structures menues ou minces, rang de Cantor Bendixson, espaces topologiques généralisés." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00442772.

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Les structures menues apparaissent dans les années 1960 de paire avec la conjecture de Vaught, dont elles sont les seuls contre-exemples possibles. Les structures minces sont introduites par Belegradek, et englobent à la fois les structures minimales et menues. Il est bien connu que les ensembles définissables d'une structure mince sont rangés par le rang de Cantor-Bendixson, lorsque l'on fixe un ensemble fini de paramètres. L'étude de ces structures est rendue difficile par le fait que si l'on augmente cet ensemble de paramètres, le rang croît, et on ne sait maîtriser sa croissance. Nous présentons des propriétés de calcul de ce rang, une condition de chaîne descendante locale sur les groupes définissables (par des formules faisant intervenir des paramètres de la clôture algébrique d'un ensemble fini), ainsi qu'une notion de presque stabilisateur local. Nous en déduisons des propriétés algébriques des structures minces : un corps mince de caractéristique positive est localement de dimension finie sur son centre (une réponse au problème 6.1.5 de Wagner, Simple Theories), et un groupe mince infini a un sous groupe abélien infini (cela répond en particulier à la question 2.8 de Wagner, "Groups in simple theories"). Nous nous intéressons ensuite aux structures menues infiniment définissables, et montrons que les groupes d'arité finie infiniment définissables (par des formules n'utilisant que les paramètres d'un ensemble fini) sont l'intersection de groupes définissables (réponse au problème 6.1.14 du livre de Wagner). Nous étendons le résultat aux demi-groupes, anneaux, corps, catégories et groupoïdes infiniment définissables (toujours avec un nombre fini de paramètres), et donnons des résultats de définissabilité locale pour les groupes et corps simples et menus, infiniment définissables sur un ensemble quelconque de paramètres. Enfin, nous réintroduisons le rang de Cantor dans son contexte topologique et montrons que la dérivée de Cantor peut être vue comme un opérateur de dérivation dans un semi-anneau d'espaces topologiques. Dans l'idée de trouver un rang de Cantor global pour les théories stables, nous essayons de nous débarrasser du mot dénombrable omniprésent lorsque l'on fait de la topologie, en le remplaçant par un cardinal régulier k. Nous développons une notion d'espace k-métrique, de k-topologie, de k-compacité etc. et montrons un k-analogue du lemme de métrisabilité d'Urysohn, et du théorème de Cantor-Bendixson.

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Souza, Sandra Elizabeth [UNESP]. "Dinâmica espaço-temporal de danos do cancro basal em Eucalyptus grandis." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/105452.

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Made available in DSpace on 2014-06-11T19:35:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-12-17Bitstream added on 2014-06-13T20:25:43Z : No. of bitstreams: 1 souza_se_dr_botfca.pdf: 819772 bytes, checksum: f7cd95ae9d4f5c4dc21861b150059d3e (MD5) Em três povoamentos de Eucalyptus grandis na região norte do Estado de São Paulo, foi realizado um estudo com objetivo de conhecer a dinâmica espaço-temporal do cancro basal, quantificar os danos no volume e efeito na qualidade da madeira. Foram instaladas nove parcelas de 7500 m², com 1000 árvores de E. grandis, procedência Santa Rita do P. Quatro-SP, origem Coffs Harbour, dos plantios seminais em solos de areia franca AQ1, AQ3 (10 a 15% de argila) e textura franco-argila-arenosa LEm2 (26 a 35% de argila). As avaliações foram realizadas em nove mil árvores com idade de dois anos. A incidência foi monitorada individualmente de acordo com a presença ou ausência da doença e a severidade, mediante o uso de uma escala diagramática de notas. Foram feitas avaliações nos anos 2000, 2001 e 2002, o que gerou 26 mapas de evolução da doença. Os resultados permitiram concluir que: (1) A incidência média do cancro basal foi influenciado pelo tipo de solo AQ3 (0,25%), AQ1 (0,21%) e LEm2 (0,09%); (2) Os valores do índice de dispersão (ID) foram > 1, para os tamanhos de quadrat 2x4, 5x2, 5x4 e 5x10; os valores de log (A) = log (Vobs) e log de (b) = log (Vbin) foram maiores que 1 e diferentes de zero, sugerindo uma tendência à agregação independente do tipo de solo; (3) 54,6% dos focos foram unitários, indicando que o cancro basal inicia-se com focos de apenas uma árvore; 80,8% dos focos apresentam maior comprimento na direção entre as linhas de plantio do que na direção da linha; focos maiores ocorreram no solo AQ3, que apresentaram-se menos compactos; a disseminação do cancro nesses povoamentos parece ter sido via sementes através das mudas; 89,1% dos mapas apresentaram focos com tamanho médio inferior a 10 árvores, no solo AQ3 em 10,9% dos focos o tamanho variou entre 11 a 30 árvores e nenhum foco foi formado acima de 30 árvores;... A study was carried out in three Eucalyptus grandis stands in the northern region of the State of São Paulo, in order to provide information on the spatio-temporal dynamics of eucalyptus canker, evaluate volume losses, and determine the effect of the disease on wood quality. Nine 7500 m² plots (10×100) containing 1000 E. grandis trees from Santa Rita do P. Quatro-SP (origin: Coffs Harbour), in seed plantations on soils classified as loamy sands, AQ1 and AQ3 (10 to 15% clay), and on a silty-clay-loam-textured soil, LEm2 (26 – 35% clay). Evaluations were made in nine thousand two-year-old trees. Incidence was monitored individually according to the presence or absence of the disease. Severity was evaluated through the use of a diagrammatic rating scale. Evaluations were made in 2000, 2001, and 2002, and 26 disease progress maps were generated. The results allowed us to conclude that: (1) The mean incidence of eucalyptus canker followed a trend that matched the soil types:AQ3 (0.25%), AQ1(0.21.%), and LEm2 (0.09%); (2) The ID values were > 1 for quadrat sizes equal to 2×4, 5×2, 5×4, and 5×10; The log (A) = log (Vobs) and log (b) = log (Vbin) values were higher than 1 and different from zero, suggesting a tendency for aggregation, regardless of soil type; (3) 54.6% of the foci were single-unit, indicating that eucalyptus canker starts with single-tree foci; 80.8% of the foci had greater lengths between planting rows than along the rows; larger foci occurred in the AQ3 soil, which were less compact; canker dissemination in those stands seemed to have occurred via seeds through the seedlings; 89.1% of the maps had foci with mean sizes smaller than 10 trees in the AQ3 soil; in 10.9% of the foci the size ranged between 11 and 30 trees, and no focus formed at sizes above 30 trees; the ICF and ICFNU values were not close nor very far from ...(Complete abstract click electronic access below)

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Souza, Sandra Elizabeth 1959. "Dinâmica espaço-temporal de danos do cancro basal em Eucalyptus grandis /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/105452.

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Orientador: Edson Luiz Furtado Banca: Marli Teixeira de Almeida Minhoni Banca: Claudio Angeli Sansígolo Banca: Waldir Cintra de Jesus Junior Banca: Celso Garcia Auer Resumo: Em três povoamentos de Eucalyptus grandis na região norte do Estado de São Paulo, foi realizado um estudo com objetivo de conhecer a dinâmica espaço-temporal do cancro basal, quantificar os danos no volume e efeito na qualidade da madeira. Foram instaladas nove parcelas de 7500 m², com 1000 árvores de E. grandis, procedência Santa Rita do P. Quatro-SP, origem Coffs Harbour, dos plantios seminais em solos de areia franca AQ1, AQ3 (10 a 15% de argila) e textura franco-argila-arenosa LEm2 (26 a 35% de argila). As avaliações foram realizadas em nove mil árvores com idade de dois anos. A incidência foi monitorada individualmente de acordo com a presença ou ausência da doença e a severidade, mediante o uso de uma escala diagramática de notas. Foram feitas avaliações nos anos 2000, 2001 e 2002, o que gerou 26 mapas de evolução da doença. Os resultados permitiram concluir que: (1) A incidência média do cancro basal foi influenciado pelo tipo de solo AQ3 (0,25%), AQ1 (0,21%) e LEm2 (0,09%); (2) Os valores do índice de dispersão (ID) foram > 1, para os tamanhos de quadrat 2x4, 5x2, 5x4 e 5x10; os valores de log (A) = log (Vobs) e log de (b) = log (Vbin) foram maiores que 1 e diferentes de zero, sugerindo uma tendência à agregação independente do tipo de solo; (3) 54,6% dos focos foram unitários, indicando que o cancro basal inicia-se com focos de apenas uma árvore; 80,8% dos focos apresentam maior comprimento na direção entre as linhas de plantio do que na direção da linha; focos maiores ocorreram no solo AQ3, que apresentaram-se menos compactos; a disseminação do cancro nesses povoamentos parece ter sido via sementes através das mudas; 89,1% dos mapas apresentaram focos com tamanho médio inferior a 10 árvores, no solo AQ3 em 10,9% dos focos o tamanho variou entre 11 a 30 árvores e nenhum foco foi formado acima de 30 árvores;...(Resumo completo, clicar acesso eletrônico abaixo) Abstract: A study was carried out in three Eucalyptus grandis stands in the northern region of the State of São Paulo, in order to provide information on the spatio-temporal dynamics of eucalyptus canker, evaluate volume losses, and determine the effect of the disease on wood quality. Nine 7500 m² plots (10×100) containing 1000 E. grandis trees from Santa Rita do P. Quatro-SP (origin: Coffs Harbour), in seed plantations on soils classified as loamy sands, AQ1 and AQ3 (10 to 15% clay), and on a silty-clay-loam-textured soil, LEm2 (26 - 35% clay). Evaluations were made in nine thousand two-year-old trees. Incidence was monitored individually according to the presence or absence of the disease. Severity was evaluated through the use of a diagrammatic rating scale. Evaluations were made in 2000, 2001, and 2002, and 26 disease progress maps were generated. The results allowed us to conclude that: (1) The mean incidence of eucalyptus canker followed a trend that matched the soil types:AQ3 (0.25%), AQ1(0.21.%), and LEm2 (0.09%); (2) The ID values were > 1 for quadrat sizes equal to 2×4, 5×2, 5×4, and 5×10; The log (A) = log (Vobs) and log (b) = log (Vbin) values were higher than 1 and different from zero, suggesting a tendency for aggregation, regardless of soil type; (3) 54.6% of the foci were single-unit, indicating that eucalyptus canker starts with single-tree foci; 80.8% of the foci had greater lengths between planting rows than along the rows; larger foci occurred in the AQ3 soil, which were less compact; canker dissemination in those stands seemed to have occurred via seeds through the seedlings; 89.1% of the maps had foci with mean sizes smaller than 10 trees in the AQ3 soil; in 10.9% of the foci the size ranged between 11 and 30 trees, and no focus formed at sizes above 30 trees; the ICF and ICFNU values were not close nor very far from ...(Complete abstract click electronic access below) Doutor

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Parreira, Paula Alexandra Ravasqueira. "Incidência do cancro do estômago e do pulmão : um estudo espacio-temporal na região sul de Portugal Continental entre 2000-2008." Master's thesis, Universidade Nova de Lisboa. Escola Nacional de Saúde Pública, 2011. http://hdl.handle.net/10362/9401.

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RESUMO - Enquadramento/Objectivos: As doenças oncológicas constituem a segunda causa de morte em Portugal, e têm um profundo impacto psicossocial, não só pela sua elevada incidência e mortalidade mas também pelos enormes custos envolvidos na sua prevenção, tratamento e reabilitação. De acordo com estudos anteriores, existem disparidades geográficas na incidência da doença oncológica. É por isso indispensável caracterizar e analisar as diferentes distribuições espaciais no tempo e no espaço, para controlar a doença e promover a saúde, contribuindo ao mesmo tempo para uma melhor compreensão da etiologia da doença. Este projecto compreende 3 objectivos principais que são: a caracterização de distribuição espacio-temporal do cancro do pulmão e do cancro do estômago, separadamente e em conjunto, na região sul de Portugal Continental (abrangida pelo ROR-Sul) no espaço temporal de 2000 a 2008, procurando identificar potenciais áreas de risco no desenvolvimento destes tumores. Metodologia: Numa primeira fase realizou-se um estudo descritivo das taxas de incidência dos tumores aqui retratados por idades, por sexo, por ano e por distritos. Posteriormente com o objectivo de identificar a presença de áreas de elevada incidência, procedeu-se à análise de clustering espacio-temporal das taxas de incidência ao nível dos concelhos na região do estudo, em 2000-2008. Resultados: Os resultados da análise descritiva revelaram que ambos os tumores são mais incidentes nos homens do que nas mulheres e que estes são igualmente mais incidentes em pessoas com mais de 75 anos. A análise de clustering espacio temporal permitiu verificar a existência um padrão geográfico heterogéneo da incidência de ambos os tumores, da qual resultaram 3 clusters para o cancro do estômago e 2 clusters para o cancro do pulmão (p <0,001). Os clusters do estômago pertencem maioritariamente à região do Alentejo e os clusters do cancro do pulmão à região da grande Lisboa. Conclusões: Os resultados da análise de clustering demonstraram um padrão heterogéneo da distribuição da incidência dos dois cancros na região e período temporal do estudo. As zonas identificadas de elevado risco são diferentes para ambos o tumores. A região que apresenta maior risco para o desenvolvimento do cancro do estômago é o Alentejo e do pulmão é o distrito de Lisboa. ABSTRACT - Background/Objectives: Oncologic diseases are the second main cause of death in Portugal and have a strong impact, not only for its high incidence and mortality, but also by its strong psychosocial impact on patients and their families with significant repercussions in social and economic structures. According with previous studies, there are strong geographical disparities in the incidence of malignant disease. It is therefore essential characterize the spatiotemporal distribution in order to control the disease and promoting health, contributing to a better understanding of disease etiology. This project comprises three main objectives which are: the characterization of spatialtemporal distribution of lung cancer and stomach cancer, separately and together, in the southern region of mainland Portugal (covered by ROR-Sul) in the timeline from 2000 to 2008, seeking to identify potential areas of risk in developing these tumors. Methodology: Firstly was preformed a descriptive analysis of incidences ratios distribution by age, and gender, per year and per districts. After, with the objective to identify high incidence areas, it was preformed a spatiotemporal analyses, using spatial scan statistics, to identify significant clusters of high incidences. Results: Statistic descriptive showed that incidences of these particular cancers are higher in man than in woman, and the critical age group was 75+. The spatiotemporal analyzes showed high asymmetries in both cancer incidences. According these results was indentified three main clusters for stomach cancer and two main clusters for lung cancer in different periods of time (p ≤ 0,001). The lung cancer clusters are composed by municipalities from the regions of Lisboa, while the stomach cancer clusters, mainly include municipalities from the Alentejo region. Conclusions: The clustering analysis results showed a marked heterogeneity in the incidence of lung and stomach cancer among the different regions of the southern area of the country. Overall, the region that is considered at higher risk for developing stomach cancer is the interior region of Alentejo. Lisbon district is the region that presents a major risk for lung cancer developing.

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Rosa, Fabíola. "Recantando muitos cantos: a música caipira como espaço de articulação de encontros." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/27/27157/tde-31052017-101546/.

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Este trabalho pretende tratar a música caipira, nosso objeto da pesquisa, sob um ponto de vista transcultural, onde, além de evidenciarmos a relação desta com as manifestações portuguesas, indígenas e negras - já largamente comentadas na bibliografia sobre o assunto, vamos procurar também traços, ou reminiscências, de música italiana. O fenômeno da imigração italiana no início do século XX fez parte de um projeto político que visava o aprimoramento das condições morais da sociedade brasileira. Por outro lado havia os habitantes dos espaços rurais do estado de São Paulo, os caipiras, que concentravam grande parte das características consideradas indesejáveis para os intelectuais urbanizados que visavam o progresso do país. Assim, graças à expansão das grandes fazendas na região rural do estado e do assentamento de colônias italianas também no interior, os caipiras estiveram expostos à convivência com estes trabalhadores italianos. Passamos a nos perguntar a respeito de como teria se dado o encaminhamento deste amálgama de culturas (nativo x italiano), especificamente na música. Propusemo-nos a procurar o quê de italiano haveria na música dos nativos. Escolhemos a música caipira por ser um gênero que entrou em ascensão em um momento próximo da chegada dos imigrantes ao país, portanto era a manifestação musical de um grupo que esteve diretamente ligado aos italianos. Acreditamos que estes eventos mereçam ainda mais dedicação por parte dos pesquisadores, uma vez que manifestado o alto grau de possibilidades envolvidas na interação de diversas culturas, estas ainda necessitem de mais colaborações que tratem de elucidá-las. This work intends to treat the caipira music, our object of research, from a transcultural point of view, where, in addition to showing its relation with the Portuguese, Indian and Black manifestations - already widely commented on in the bibliography on the subject, we will also look for traces , Or reminiscences, of Italian music. The phenomenon of Italian immigration in the early 20th century was part of a political project aimed at improving the moral conditions of Brazilian society. On the other hand, there were the inhabitants of the rural areas of the state of São Paulo, the Caipiras, who concentrated much of the characteristics considered undesirable for the urbanized intellectuals that aimed the progress of the country. Thus, thanks to the expansion of the large farms in the rural area of the state and the settlement of Italian colonies also inland, the Caipiras were exposed to coexistence with these Italian workers. We began to wonder how the referral of this mixture of cultures (native x Italian), specifically in music, would have taken place. We set out to find out what Italian would be in the music of the natives. We chose caipira music because it was a genre that came on the rise at a time when immigrants arrived in the country, so it was the musical manifestation of a group that was directly connected to the Italians. We believe that these events deserve even greater dedication on the part of the researchers, since they expressed the high degree of possibilities involved in the interaction of diverse cultures, these still need more collaborations that try to elucidate them.

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Granados, Ybarra Gianinna Consuelo. "Articulando el espacio sanitario. Nuevo hospital para San Juan de Lurigancho – Canto Grande." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2021. http://hdl.handle.net/20.500.12404/20252.

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Tras la aparición del Coronavirus a nivel mundial se ha visto cuán importante es la implementación de infraestructuras hospitalarias para afrontar nuevas necesidades en el sector salud. El Perú se ha visto muy afectado debido a que muchos de los hospitales se encuentran desabastecidos o colapsados como es el caso del Hospital de San Juan de Lurigancho en Canto Grande. Al ser este hospital el más importante en el distrito de San Juan de Lurigancho cuya densidad demográfica es de aproximadamente 1 millón de habitantes. El proyecto busca desde lo urbano la reorganización de una supermanzana a partir de la disposición de los principales equipamientos urbanos: mercado, colegio y hospital; y desde lo arquitectónico, brindar a los usuarios una mejor calidad de los servicios debido al tiempo que las personas se encuentran en atención o tratamiento dentro del hospital de Canto Grande. El diseño de los espacios se da a través de la configuración de patios internos, los cuales permiten la integración física y visual entre cada unidad al interior del hospital y que con la incorporación de jardines y espacios de integración mejoran el nivel de bienestar y recuperación del usuario; del mismo modo, el diseño de un gran espacio integrador que ayude a la orientación del público y paciente. Todo este desarrollo no deja de lado la correcta y eficiente funcionalidad del hospital, la cual es una variable importante debido a su nivel de complejidad.

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Lira, Andréa Braga de. "Utilização do espaço sonoro por quatro espécies de Hylidae do Cerrado no Brasil Central." reponame:Repositório Institucional da UnB, 2017. http://repositorio.unb.br/handle/10482/31258.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Florestal, Programa de Pós-Graduação em Ciências Florestais, 2017. Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2017-12-22T11:47:55Z No. of bitstreams: 1 2017_AndréaBragadeLira.pdf: 1918462 bytes, checksum: 9f8ebe94252d76685e51d6d9d91c4fbd (MD5) Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2018-02-20T16:06:27Z (GMT) No. of bitstreams: 1 2017_AndréaBragadeLira.pdf: 1918462 bytes, checksum: 9f8ebe94252d76685e51d6d9d91c4fbd (MD5) Made available in DSpace on 2018-02-20T16:06:27Z (GMT). No. of bitstreams: 1 2017_AndréaBragadeLira.pdf: 1918462 bytes, checksum: 9f8ebe94252d76685e51d6d9d91c4fbd (MD5) Previous issue date: 2018-02-20 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). Os processos de comunicação em anuros têm se sido foco de diversas pesquisas que avaliam interações inter-específicas e a maneira como as espécies utilizam o espaço acústico através do canto de anúncio. As características dos parâmetros do canto são de fato, importantes para a co-ocorrência de hilídeos em sítios de reprodução. Neste estudo, o período em que foi permitido obter o maior registro de gravações foi durante a estação chuvosa. Para todos os dados levantados em campo, os valores espectrais do canto se diferem quantos aos valores médios e ocupam espaços acústicos característicos. A sobreposição do nicho acústico foi menor que o esperado ao acaso, indicando que ocorra estruturação da assembléia no uso dos recursos. As taxas de repetição do canto foram explicadas por variáveis obtidas para cada indivíduo gravado, sendo elas: comprimento rostro-cloacal, temperatura e distância do animal para a água. The processes of communication in anurans have been the focus of several researches that evaluate inter-specific interactions and the way in which the species use the acoustic space through the advertisement call. The characteristics of the call parameters are in fact important for the co-occurrence of hilídeos in breeding sites. In this study, the period in which it was allowed to obtain the largest recording record was during the rainy season. For all the data collected in the field, the spectral values of the call differ as much as the mean values and occupy characteristic acoustic spaces. The overlapping of the acoustic niche was less than expected at random, indicating that assembly structuring occurs in the use of resources. The rates repetition of call were explained by variables obtained for each recorded individual, being: rostrum-cloacal length, temperature and distance from the animal to the water.

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Boufraqech, Myriem. "Implication des espèces réactives de l’oxygène (ROS) dans la radiocarcinogenèse thyroïdienne." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA11T069/document.

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La radiothérapie est utilisée seule ou en association avec la chimiothérapie dans le traitement de plus de 50% des cancers. En dépit des nombreux progrès dans le but d’améliorer le rapport bénéfice/risque, l’irradiation est à l’origine de nombreux effets secondaires. Une des origines connues des cancers de la thyroïde est l’exposition pendant l’enfance aux radiations ionisantes, soit accidentelles, soit suite à un traitement par radiothérapie externe pour une autre pathologie. Les mécanismes par lesquels les radiations ionisantes provoquent l’apparition d’un cancer de la thyroïde sont nombreux et encore incomplètement connus. Les radiations ionisantes sont des agents génotoxiques qui induisent des dommages au niveau de l’ADN telles que des cassures et des aberrations chromosomiques. Bien que les mécanismes qui sous-tendent ces effets ne soient pas complètement compris, il est généralement admis que les radiations ionisantes induisent des dommages à l’ADN soit de manière directe soit de manière indirecte en générant des espèces réactives de l’oxygène (ROS). Durant ma thèse, nous avons étudié le rôle des ROS produit lors de l’irradiation dans la génération des dommages à l’ADN dans les cellules thyroïdiennes. Nos résultats montrent que les ROS produites après irradiation participent à la formation des réarrangements chromosomiques RET/PTC1 retrouvés dans 70% des cancers papillaires radioinduits. Les ROS engendrées par la radiolyse de l’eau ont une durée de vie extrêmement courte ce qui limite leur diffusion. Néanmoins, par des mécanismes redox, ils provoquent des modifications au niveau cellulaire qui conduisent à leur tour à l’activation de systèmes générateurs de ROS, parmi lesquels on trouve les NADPH oxydases. Nos résultats montrent que l’irradiation induit l’expression de la NADPH oxydase DUOX1 via la sécrétion d’IL-13, plusieurs jours après l’exposition aux radiations ionisantes. L’inactivation de DUOX1 par ARNs interférents diminue de manière significative les dommages de l’ADN observés plusieurs jours après irradiation. Ces résultats suggèrent un rôle de DUOX1 dans le stress oxydatif chronique qui contribue à l’instabilité génétique Radiotherapy is used alone or in combination with chemotherapy to treat over 50% of cancers. Despite much progress in order to improve the benefit / risk ratio, the radiation causes many side effects. One of the known origins of thyroid cancer is exposure during childhood to ionizing radiation, either accidentally or as a result of external radiation therapy for another disease. The mechanisms by which ionizing radiation causes the appearance of thyroid cancer are numerous and not yet fully known. Ionizing radiations are genotoxic agents that induce DNA damage such as breaks and chromosomal aberrations. Although the mechanisms underlying these effects are not completely understood, it is generally accepted that ionizing radiations induce DNA damage either directly or indirectly by generating reactive oxygen species (ROS). During my PhD, we studied the role of ROS produced during irradiation in the generation of DNA damage in thyroid cells. Our results show that ROS produced after irradiation participate in the formation of RET/PTC1 rearrangements found in 70% of radiation-induced papillary cancers. ROS generated by radiolysis of water have a very short lifetime that limits their diffusion. However, by redox mechanisms, they cause changes at the cellular level, which in turn lead to the activation of ROS generating systems, which include the NADPH oxidases. Our results show that irradiation induces the expression of NADPH oxidase DUOX1 via the secretion of IL-13, several days after exposure to ionizing radiation. Inactivation of DUOX1 by interfering RNAs significantly reduces the DNA damage observed several days after irradiation. These results suggest a role DUOX1 in chronic oxidative stress that contributes to genetic instability

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Moncheu, Kamga Koleber Victor. "Histiocytofibrome malin rétropéritonéal révélé par une thrombose veineuse cave inférieure : à propos d'une observation et revue de la littérature." Bordeaux 2, 1998. http://www.theses.fr/1998BOR2M011.

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Tiradentes, Leomar [UNESP]. "O Canto da araponga: possibilidades de um turismo no espaço rural da microrregião de Viçosa - MG." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/95705.

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Made available in DSpace on 2014-06-11T19:27:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-12-14Bitstream added on 2014-06-13T18:32:06Z : No. of bitstreams: 1 tiradentes_l_me_rcla.pdf: 6800688 bytes, checksum: 55630e04f10f610363052b9504b390bc (MD5) Na presente pesquisa analisamos as atividades turísticas em quatro propriedades rurais do Município de Araponga na Microrregião da Zona da Mata de Viçosa - MG, identificando suas diferentes realidades, seu processo de construção, desenvolvimento e compreensão quanto ao modo como elas interagem no espaço local. De caráter exploratório e de natureza qualitativa, utilizamos o estudo de caso como metodologia, tendo como instrumentos a observação e as entrevistas semi-estruturadas. O objetivo principal desta pesquisa foi analisar o turismo no espaço rural como fator de desenvolvimento das propriedades que já realizam algum tipo de oferta turística. Os resultados indicaram que as atividades turísticas estão inseridas na realidade das propriedades rurais, coexistindo com as práticas agropecuárias cotidianas, e com suas diferentes terminologias para as várias realidades turísticas no campo tais como pousada rural, camping, entre outras, que não abordam necessariamente a mesma modalidade de atividades. De maneira geral, o turismo no espaço rural encontra nas propriedades rurais pesquisadas, um local adequado para o seu pleno aproveitamento, desde que realizado de maneira planejada e responsável. At the present research we analyse tourist activities in four rural properties of Araponga town at Zona da Mata Micro region of Viçosa in the state of Minas Gerais, it identifying your different realities, your construction process, development and understanding like they interact in the local space. Of exploring character and qualitative nature, we use the studying of case like methodology, it having like tools observation and interviews semi-structured. The main objective of this research was analyse tourism in rural space like development factor of properties have already made some kind of tourist offer. The results indicated that tourist activities are inserted in the reality of rural properties, it existing together with daily farming and cattle raising practices, it there being different terminologies to several tourist realities at the country like rural inn, camping, and others, it doesn't necessarily approaching the same kind of activities. In general, the tourism in rural space finds in researched rural properties an appropriate local to its full utilization since it put into practice in some planned and answerable way.

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Gouvêa, Alana Adães de. "A casa mineira como um canto do mundo: da inocência de Taunay à universalidade do espaço." Centro de Ensino Superior de Juiz de Fora (CES/JF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/6533.

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Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-04-03T12:59:08Z No. of bitstreams: 1 alanaadaesdegouvea.pdf: 1119795 bytes, checksum: 2ad8c960d9e73e61f5e6a9c75b28625e (MD5) Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-04-03T19:05:02Z (GMT) No. of bitstreams: 1 alanaadaesdegouvea.pdf: 1119795 bytes, checksum: 2ad8c960d9e73e61f5e6a9c75b28625e (MD5) Made available in DSpace on 2018-04-03T19:05:02Z (GMT). No. of bitstreams: 1 alanaadaesdegouvea.pdf: 1119795 bytes, checksum: 2ad8c960d9e73e61f5e6a9c75b28625e (MD5) Previous issue date: 2017-06-30 PROQUALI (UFJF) A presente pesquisa pretende fazer um exame da obra Inocência, de Visconde de Taunay. Tal análise se apoia nos conceitos de espaço, como proposto pela fenomenologia de Gaston Bachelard e de hospitalidade, conforme o pensamento de Jacques Derrida. Esta investigação busca, portanto, demorar-se sobre a casa, enxergando-a como um espaço que sugere identidade ao ser humano e que está intimamente ligado à hospitalidade como ato que pressupõe o oferecimento de si e que torna a casa um canto do mundo. Como refletem Gaston Bachelard e Emmanuel Levinas, sua posse e uso transitam entre os sonhos e as necessidades não gerando, necessariamente, a intimidade do acolhimento. A partir do momento em que se considera que o texto literário é um dos lugares privilegiados dos estudos na busca da compreensão dos conflitos e das dúvidas que acometem o ser humano, essa pesquisa almeja evidenciar as peculiaridades e atualidades dos registros de Taunay, visualizando a casa do mineiro, os seus atrativos e os seus segredos. Assim, a partir do regional procura-se chegar a uma percepção do que se pode chamar de casa universal. Além disso, os seus cantos e (des)encantos, as suas características, os estranhamentos que acontecem quando nela se recebe o outro, oferecem as mais intrincadas e diversificadas simbologias. Isso porque a casa, embora fechada em si mesma, está aberta para o mundo, realçando o contraste entre o dentro e o fora, o eu e o outro, as partidas e chegadas. No que concerne a uma conceituação da hospitalidade frente a uma realidade de ontem e de hoje, pode-se demonstrar as incertezas do próprio conceito, a sua ambiguidade, a sua incondicionalidade e as suas consequências no trato público e pessoal das convivências e dos preceitos sociais. É nessa direção que o presente exame tem o seu lugar, qual seja, uma leitura de Inocência, buscando entender melhor o referencial da habitação, considerando as hipóteses apresentadas e contribuindo para o crescimento do acervo crítico de Visconde de Taunay. The present research aims at making a study of the work Inocência, of Viscount of Taunay. This analysis is based on the concepts of space, as proposed by Gaston Bachelard's phenomenology and hospitality, according to the thinking of Jacques Derrida. This investigation, therefore, seeks to ponder over the house, seeing it as a space that suggests identity to the human being and that is intimately connected to hospitality as an act that presupposes the offering of oneself and that makes the house a corner of the world. As Gaston Bachelard and Emmanuel Levinas reflect, the possession and use of this place pass between dreams and needs, not necessarily generating the intimacy in the the reception. Since the literary text is considered to be one of the privileged places of studies in the search for an understanding of the conflicts and doubts that affect the human being, this research aims to highlight the peculiarities and the current features of the observations of Taunay , visualizing the house of Minas, its attractions and its secrets. So, starting out from the regional, one seeks to arrive at a perception of what can be called the universal house. In addition to this, the charms and the limitations, the characteristics and the strangeness that happens when they receive the other, offer the most intricate and diversified symbolisms. This is because the house, although closed in on itself, is open to the world, highlighting the contrast between inside and outside, self and other, departures and arrivals. With regard to a conceptualization of hospitality in the face of the reality of yesterday and today, one can demonstrate the uncertainties of the the concept itself, its ambiguity, its unconditionality and its consequences in the public and personal treatment of coexistence and of social precepts. It is in this direction then that the present examination takes its place, that is, a reading of Inocência, seeking to better understand the referential of the house, considering the hypotheses presented and contributing to the growth of the critical collection of the Viscount of Taunay.

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Tiradentes, Leomar. "O Canto da araponga : possibilidades de um turismo no espaço rural da microrregião de Viçosa - MG /." Rio Claro : [s.n.], 2004. http://hdl.handle.net/11449/95705.

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Orientador: Geraldo Muller Banca: Herbe Xavier Banca: Sílvio Carlos Bray Banca: Rita de Cássia Ariza da Cruz Banca: Iandara Alves Mendes Resumo: Na presente pesquisa analisamos as atividades turísticas em quatro propriedades rurais do Município de Araponga na Microrregião da Zona da Mata de Viçosa - MG, identificando suas diferentes realidades, seu processo de construção, desenvolvimento e compreensão quanto ao modo como elas interagem no espaço local. De caráter exploratório e de natureza qualitativa, utilizamos o estudo de caso como metodologia, tendo como instrumentos a observação e as entrevistas semi-estruturadas. O objetivo principal desta pesquisa foi analisar o turismo no espaço rural como fator de desenvolvimento das propriedades que já realizam algum tipo de oferta turística. Os resultados indicaram que as atividades turísticas estão inseridas na realidade das propriedades rurais, coexistindo com as práticas agropecuárias cotidianas, e com suas diferentes terminologias para as várias realidades turísticas no campo tais como pousada rural, camping, entre outras, que não abordam necessariamente a mesma modalidade de atividades. De maneira geral, o turismo no espaço rural encontra nas propriedades rurais pesquisadas, um local adequado para o seu pleno aproveitamento, desde que realizado de maneira planejada e responsável. Abstract: At the present research we analyse tourist activities in four rural properties of Araponga town at Zona da Mata Micro region of Viçosa in the state of Minas Gerais, it identifying your different realities, your construction process, development and understanding like they interact in the local space. Of exploring character and qualitative nature, we use the studying of case like methodology, it having like tools observation and interviews semi-structured. The main objective of this research was analyse tourism in rural space like development factor of properties have already made some kind of tourist offer. The results indicated that tourist activities are inserted in the reality of rural properties, it existing together with daily farming and cattle raising practices, it there being different terminologies to several tourist realities at the country like rural inn, camping, and others, it doesn't necessarily approaching the same kind of activities. In general, the tourism in rural space finds in researched rural properties an appropriate local to its full utilization since it put into practice in some planned and answerable way. Mestre

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Dias, Alexandre Ferreira de Souza. "Competição por espaço acústico : adaptações de cantos de aves em uma zona de alta biodiversidade do Brasil Central." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/14853.

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Tese (doutorado)—Universidade de Brasília, Programa de Pós-Graduação em Ecologia, 2013. Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2013-12-12T15:24:04Z No. of bitstreams: 1 2013_AlexandreFerreiraSouzaDias.pdf: 3127038 bytes, checksum: 91fe39fbb3c020442ef7c35446d16b3a (MD5) Approved for entry into archive by Guimaraes Jacqueline(jacqueline.guimaraes@bce.unb.br) on 2013-12-16T12:13:18Z (GMT) No. of bitstreams: 1 2013_AlexandreFerreiraSouzaDias.pdf: 3127038 bytes, checksum: 91fe39fbb3c020442ef7c35446d16b3a (MD5) Made available in DSpace on 2013-12-16T12:13:18Z (GMT). No. of bitstreams: 1 2013_AlexandreFerreiraSouzaDias.pdf: 3127038 bytes, checksum: 91fe39fbb3c020442ef7c35446d16b3a (MD5) Cada vez mais estudos têm mostrado que aves são capazes de modificar seu canto quando sujeitas a ruídos interferentes, sejam de fonte antrópica (como ruídos urbanos) ou biótica (cantos de outras aves). O presente estudo investigou comunidades de aves no Cerrado registradas com gravadores automáticos Song Meter e em regiões urbanas de Brasília gravadas com microfone direcional, analisando-se a influência de diferentes níveis de ruído urbano no canto de cinco espécies, e o grau de sobreposição da atividade de canto de cinco espécies durante o coro matutino em áreas de cerrado e borda de mata na Fazenda Água Limpa. Inicialmente apresentamos uma descrição do coro matutino, composto por 111 espécies, e a quantidade de espécies que exibem atividade vocal por estrato de tempo. Observamos uma tendência à redução no número de espécies entre 6h e 7h nas áreas de cerrado (r = -0.53, p = 0.07) e um aumento no número de espécies em áreas de borda de mata para o mesmo horário (r = 0.82, p = 0.001). A hipótese de que espécies com cantos com maior similaridade, ou seja, que utilizam bandas de frequência mais próximas, distribuem temporalmente os seus cantos de modo a não se sobreporem ao longo do tempo não se confirmou, porém encontramos indícios de particionamento do espaço acústico nos dados que indicam picos assincrônicos de atividade de canto para os pares de espécies Camptostoma obsoletum & Tyrannus melancholicus, e Cyclarhis gujanensis & Saltator similis gravadas em áreas de borda de mata. Já os resultados relativos às espécies gravadas em áreas urbanas mostraram uma correlação positiva significativa entre a frequência mínima do canto e o nível de ruído urbano para as espécies Troglodytes musculus (r = 0,67, p < 0.001), e Furnarius rufus (r = 0.46, p < 0.001). Por fim, foi analisada a eficácia do programa Song Scope em gerar reconhecedores automáticos para seis espécies. Para quatro espécies o programa apresentou um alto índice de detecções corretas (acima de 50%), enquanto que para duas delas, cujos cantos são mais complexos e mais variáveis, o índice de positivos verdadeiros foi abaixo de 30%. Tais dados mostram o alto potencial de reconhecedores automáticos para se avaliar comunidades de aves em áreas grandes onde o emprego de observadores humanos qualificados é limitado. ______________________________________________________________________________ ABSTRACT A growing body of studies show that birds are capable of modifying their song when subject to interfering noises, either anthropogenic (e.g. urban noise) or biotic (songs from other birds). The present study investigated bird communities in the Cerrado biome recorded with Song Meter automatic equipment and in urban regions in Brasília, Brazil, recorded with a directional microphone, by analyzing the influence of different levels of urban noise on the song of five species, and the degree of overlap of singing activity between five species during the dawn chorus in cerrado and gallery forest edge areas at the Água Limpa Farm. Initially we present a description of the dawn chorus, comprising 111 species, and the number of species exhibiting vocal activity by time strata. We observed a trend towards reduction in the number of species vocally active between 6h and 7h in cerrado areas (r = -0.53, p = 0.07) and an increase in the number of species in gallery forest edge areas for the same period (r = 0.82, p = 0.001). The hypothesis that species with more similar songs, i.e. which sing in closer frequency bandwidths, distribute their songs temporally so that they do not overlap over time was not confirmed; however we found evidence of acoustic space partition in the data that indicate asynchronous peaks of song activity for the species pairs Camptostoma obsoletum & Tyrannus melancholicus, and Cyclarhis gujanensis & Saltator similis recorded in forest gallery areas. The results relative to species recorded in urban areas showed a positive significant correlation between minimum song frequency and the level of urban noise for the species Troglodytes musculus (r = 0,67, p < 0.001), and Furnarius rufus (r = 0.46, p < 0.001). Finally, we analyzed the effectiveness of the Song Scope software in generating automatic recognizers for six species. For four species the software showed high indexes of correct detections (above 50%), whereas for two of them, whose songs are more complex and more variable, the false positive index was below 30%. Such data show the high potential of automatic recognizers to evaluate bird communities in large areas where the use of qualified human observers is limited.

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Jiao, Wenjuan. "APOBEC1 cytidine désaminase induit la mutagenèse de l'ADN chez différentes espèces animales." Thesis, Université de Paris (2019-....), 2019. http://www.theses.fr/2019UNIP7181.

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Les cytidine desaminases APOBEC1 (A1) ont une préférence claire pour le substrat pour l'ARN. De plus, il a été démontré que quelques enzymes A1 sont actives sur l'ADN simple brin, ce qui reflète les activités décrites pour les enzymes APOBEC3. Comme APOBEC3A (A3A) humain, APOBEC3B (A3B) humain et des enzymes apparentés appartenant au spectre des mammifères placentaires peuvent introduire des mutations dans l'ADN nucléaire conduisant à des génomes cancéreux, nous avons exploré la menace mutagène de la cytidine désaminase A1 sur l'ADN chromosomique.Utilisation de la 3D-PCR pour détecter des mutations spécifiques GC-AT d’APOBEC, nous avons démontré que les enzymes A1 de la vache, du porc, du chien, du lapin et de la souris avaient une spécificité de substrat intracellulaire d’ADN simple brin. Cependant, seule l'enzyme de souris était capable d'introduire des mutations dans l'ADN nucléaire. Fait intéressant, la souris A1 quitte le même contexte d’édition de dinucléotides (5’TpC) que les enzymes similaires à APOBEC3. Ces caractères ont été mis en parallèle par la désamination de l'ADN substitué de 5-méthylcytidine par A1 de souris, caractéristique des enzymes A3A et A3B de mammifères. L'enzyme A1 de la souris était beaucoup moins efficace que l'A3A humain et était plus proche de l'A3B humain.Au niveau expérimental, APOBEC1 chez la souris est remarquable parmi 12 enzymes de mammifères en ce sens qu’il représente une source de mutations somatiques dans le génome de la souris, alimentant potentiellement l’oncogenèse. Bien que l'ordre de Rodentia soit dépourvu d'un enzyme de type A3A, il semble qu'APOBEC1 pourrait bien le remplacer, tout en restant beaucoup moins actif. Cela modifie le paradigme selon lequel les enzymes APOBEC3 et AID sont les seules enzymes de mutation endogènes donnant lieu à une modification non ciblée des génomes de mammifères APOBEC1 (A1) cytidine deaminases have a clear substrate preference for RNA. In addition, a few A1 enzymes have been shown to be active on single stranded DNA, mirroring the activities described for APOBEC3 enzymes. As human APOBEC3A (A3A), APOBEC3B (A3B) and related enzymes across the spectrum of placental mammals can introduce mutations in nuclear DNA leading to cancer genomes, we explored the mutagenic threat of A1 cytidine deaminases to chromosomal DNA.Using 3D-PCR to detect APOBEC specific GC to AT mutations, we demonstrated that A1 enzymes from the cow, pig, dog, rabbit and mouse have an intracellular ssDNA substrate specificity. However, only the mouse enzyme was able to introduce mutations into nuclear DNA. Interestingly, mouse A1 leaves the same dinucleotide editing context (5’TpC) as APOBEC3 like enzymes. These traits were paralleled by deamination of 5-methylcytidine substituted DNA by mouse A1 which is a feature of the mammalian A3A and A3B enzymes. Mouse A1 enzyme was far less efficient than human A3A and was closer to human A3B.At an experimental level mouse APOBEC1 is remarkable among 12 mammalian enzymes in that it represents a source of somatic mutations in mouse genome, potentially fueling oncogenesis. While the order of Rodentia is bereft of an A3A like enzyme it seems that APOBEC1 may well substitute for it, albeit remaining much less active. This modifies the paradigm that APOBEC3 and AID enzymes are the sole endogenous mutator enzymes giving rise to off-target editing of mammalian genomes

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Silva, Suelen Umbelino da [UNESP]. "Modelo dinâmico bayesiano multivariado para análise espaço-temporal de dados de área." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/116005.

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Made available in DSpace on 2015-03-03T11:52:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-29Bitstream added on 2015-03-03T12:06:57Z : No. of bitstreams: 1 000806969.pdf: 1829988 bytes, checksum: df9758a2c8b3433ccf8626a081ac6d42 (MD5) Modelagem de dados de área tem sido tema de diversas pesquisas em Estatística nas últimas décadas. Modelos espaço-temporais têm sido utilizados para lidar com esse tipo de dados de um modo natural, uma vez que muitas vezes envolvem processos que têm transições no tempo e no espaço. O avanço da tecnologia e, simultaneamente, de métodos estatísticos, têm permitido a elaboração de modelos cada vez mais estruturados para a descrição de fenômenos aleatórios complexos, cuja ideia é descrever, de forma realista, a estrutura de correlação presente nos dados, o que pode ser feito através do uso de modelos hierárquicos. Dada a importância atual da modelagem de fenômenos espaço-temporais, neste trabalho são estudadas propostas recentes apresentadas na literatura para dados espaciais de área, envolvendo modelos autorregressivos condicionais multivariados para capturar a estrutura espacial e modelos dinâmicos para capturar a estrutura temporal. Como aplicação da metodologia é estudada a distribuição espacial da mortalidade pelos cânceres de maior importância quantitativa, segundo as microrregiões administrativas do estado de São Paulo, considerando o período 1998 até 2010. Os resultados da aplicação de um modelo bayesiano hierárquico para os dados evidenciaram quais as regiões de maior risco de mortalidade no estado de São Paulo para cada um dos cânceres estudados, além de mostrar que existe forte correlação espacial entre algumas das doenças, o que constitui um resultado muito importante para os órgãos do sistema de saúde, que têm como função direcionar e alocar recursos para o tratamento e diagnóstico de tais doenças... Data modeling area has been the subject of several studies in Statistics in recent decades. Spatio-temporal models have been used to deal with this kind of data in a natural way, since they often involve processes that have transitions in time and space. The advancement of technology and simultaneously statistical methods have allowed the development of increasingly structured models for the description of complex random phenomena, whose idea is to describe realistically, the structure of this correlation in the data, which can be done through the use of hierarchical models. Given the current importance of modeling spatio-temporal phenomena, the aim of this work is study recent paper that involve multivariate conditional autoregressive models to capture the spatial and dynamic structure models to capture the temporal structure. As an application of the methodology is the spatial distribution of mortality for cancers of greater quantitative importance studied, according to the administrative microregions of the state of São Paulo, considering the period 1998 to 2010...

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Silva, Suelen Umbelino da. "Modelo dinâmico bayesiano multivariado para análise espaço-temporal de dados de área /." Presidente Prudente, 2014. http://hdl.handle.net/11449/116005.

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Orientador: Aparecida Doniseti Pires de Souza Banca: Leonardo Soares Bastos Banca: Renato Martins Assunção Resumo: Modelagem de dados de área tem sido tema de diversas pesquisas em Estatística nas últimas décadas. Modelos espaço-temporais têm sido utilizados para lidar com esse tipo de dados de um modo natural, uma vez que muitas vezes envolvem processos que têm transições no tempo e no espaço. O avanço da tecnologia e, simultaneamente, de métodos estatísticos, têm permitido a elaboração de modelos cada vez mais estruturados para a descrição de fenômenos aleatórios complexos, cuja ideia é descrever, de forma realista, a estrutura de correlação presente nos dados, o que pode ser feito através do uso de modelos hierárquicos. Dada a importância atual da modelagem de fenômenos espaço-temporais, neste trabalho são estudadas propostas recentes apresentadas na literatura para dados espaciais de área, envolvendo modelos autorregressivos condicionais multivariados para capturar a estrutura espacial e modelos dinâmicos para capturar a estrutura temporal. Como aplicação da metodologia é estudada a distribuição espacial da mortalidade pelos cânceres de maior importância quantitativa, segundo as microrregiões administrativas do estado de São Paulo, considerando o período 1998 até 2010. Os resultados da aplicação de um modelo bayesiano hierárquico para os dados evidenciaram quais as regiões de maior risco de mortalidade no estado de São Paulo para cada um dos cânceres estudados, além de mostrar que existe forte correlação espacial entre algumas das doenças, o que constitui um resultado muito importante para os órgãos do sistema de saúde, que têm como função direcionar e alocar recursos para o tratamento e diagnóstico de tais doenças... Abstract: Data modeling area has been the subject of several studies in Statistics in recent decades. Spatio-temporal models have been used to deal with this kind of data in a natural way, since they often involve processes that have transitions in time and space. The advancement of technology and simultaneously statistical methods have allowed the development of increasingly structured models for the description of complex random phenomena, whose idea is to describe realistically, the structure of this correlation in the data, which can be done through the use of hierarchical models. Given the current importance of modeling spatio-temporal phenomena, the aim of this work is study recent paper that involve multivariate conditional autoregressive models to capture the spatial and dynamic structure models to capture the temporal structure. As an application of the methodology is the spatial distribution of mortality for cancers of greater quantitative importance studied, according to the administrative microregions of the state of São Paulo, considering the period 1998 to 2010... Mestre

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Sharif, Tanveer. "Étude des effets anticancéreux de polyphénols d'origine naturelle : rôle essentiel des espèces réactives de l'oxygène et des gènes suppresseurs de tumeurs." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAJ103.

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Ce travail de recherche montre que les différentes sources de polyphénols (polyphénols de vin rouge, jus d'aronia melanocarpa, jus de cassis) ont de puissants effets chemothérapeutiques et chemopréventifs sur différentes lignées de culture cellulaires, mais également in vivo sur un modèle de tumorigenèse. Ces polyphénols inhibent la prolifération des cellules cancéreuses (leucémie lymphoblastique aigüe, cellules souches) en induisant un arrêt du cycle cellulaire et l'apoptose. Les effets anti-cancéreux sont dépendants de l' induction du stress oxydatif mettant en jeu les anions superoxydes et le peroxyde d·hydrogène qui à son tour, activent les voies de signalisation conduisant à une surexpression des gènes suppresseurs de tumeurs comme p73 et p53 et ainsi que caspase 3. Celle étude montre également que les polyphénols contrôlent la prolifération des cellules cancéreuses au niveau épigénétique en diminuant l'expression d'UHRF1 (un intégrateur épigénétique de prolifération). Cependant l'effet anticancéreux de ces polyphénols est sélectif et agit sur les cellules cancéreuses et non sur les cellules normales. Le fractionnement de ces sources riches en polyphénols et les études menées en utilisant des composés purs montrent que les effets anticancéreux sont attribués à plusieurs composés différents. Cette étude montre l' identification de cyanidine-3-glucoside et de cyanidine-3-rutinoside comme source de composés anticancéreux actifs This research work shows that different sources of polyphenols (RWPs, AMJ and blackcurrant) have strong chemotherapeutic and chemopreventive effects on several cancer cells lines (acute lymphoblastic leukemia and cancer stem cells) and also in vivo in a model of tumorigenesis in mouse. These polyphenols inhibit the proliferation of various cancer cells by inducing cell cycle arrest and apoptosis. The anti-cancer effect is dependent on the induction of oxidative stress involving superoxide anions and hydrogen peroxide which, in turn, activate the signaling pathways leading to the re-expression of tumor suppressor genes such as p73 and p53 and executor of apoptosis such as caspase 3. This study also shows that polyphenols control the proliferation of cancer cells at epigenetic level by decreasing the expression of UHRF1 (an epigenetic integrator of proliferation). Moreover, the anticancer effect of these polyphenols is selective towards cancer cells and not in normal cells. Fractionation of these rich sources of polyphenols and studies on the commercially available pure products shows that anti-cancer effects of these polyphenols involve several different compounds. This study leads to the identification of cyaniding-3-O-glucoside and cyaniding-3-O-rutinoside as active anticancer compounds

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Boufraqech, Myriem. "Implication des espèces réactives de l'oxygène (ROS) dans la radiocarcinogenèse thyroïdienne." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00747797.

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La radiothérapie est utilisée seule ou en association avec la chimiothérapie dans le traitement de plus de 50% des cancers. En dépit des nombreux progrès dans le but d'améliorer le rapport bénéfice/risque, l'irradiation est à l'origine de nombreux effets secondaires. Une des origines connues des cancers de la thyroïde est l'exposition pendant l'enfance aux radiations ionisantes, soit accidentelles, soit suite à un traitement par radiothérapie externe pour une autre pathologie. Les mécanismes par lesquels les radiations ionisantes provoquent l'apparition d'un cancer de la thyroïde sont nombreux et encore incomplètement connus. Les radiations ionisantes sont des agents génotoxiques qui induisent des dommages au niveau de l'ADN telles que des cassures et des aberrations chromosomiques. Bien que les mécanismes qui sous-tendent ces effets ne soient pas complètement compris, il est généralement admis que les radiations ionisantes induisent des dommages à l'ADN soit de manière directe soit de manière indirecte en générant des espèces réactives de l'oxygène (ROS). Durant ma thèse, nous avons étudié le rôle des ROS produit lors de l'irradiation dans la génération des dommages à l'ADN dans les cellules thyroïdiennes. Nos résultats montrent que les ROS produites après irradiation participent à la formation des réarrangements chromosomiques RET/PTC1 retrouvés dans 70% des cancers papillaires radioinduits. Les ROS engendrées par la radiolyse de l'eau ont une durée de vie extrêmement courte ce qui limite leur diffusion. Néanmoins, par des mécanismes redox, ils provoquent des modifications au niveau cellulaire qui conduisent à leur tour à l'activation de systèmes générateurs de ROS, parmi lesquels on trouve les NADPH oxydases. Nos résultats montrent que l'irradiation induit l'expression de la NADPH oxydase DUOX1 via la sécrétion d'IL-13, plusieurs jours après l'exposition aux radiations ionisantes. L'inactivation de DUOX1 par ARNs interférents diminue de manière significative les dommages de l'ADN observés plusieurs jours après irradiation. Ces résultats suggèrent un rôle de DUOX1 dans le stress oxydatif chronique qui contribue à l'instabilité génétique.

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Teixeira, Paulo Frederico de Andrade. "Performance da obra coral de Osvaldo Lacerda: rigor de escrita e o espaço do intérprete." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/27/27158/tde-18092018-164248/.

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Esta tese é parte integrante do trabalho de doutorado em Performance Musical com especialização em Regência Coral do Programa de Pós-graduação em Música da Escola de Comunicações e Artes da Universidade de São Paulo. Durante os quatro anos de doutorado foram realizados concertos, ensaios e atividades práticas desenvolvidas simultaneamente à escrita deste texto que discute questões referentes à prática de um performer. Nosso objeto central é a relação entre a escrita musical e a interpretação. Buscamos compreender, como intérpretes, quais são os espaços criativos e seus limites dentro de uma obra musical. Para isso, utilizamos a obra coral do compositor brasileiro Osvaldo Lacerda, conhecido por sua escrita rigorosa e bastante indicativa. Após uma reflexão sobre os conflitos existentes entre composição e interpretação, fizemos uma análise geral da escrita composicional de Lacerda buscando encontrar os espaços para a criatividade do intérprete. Em seguida, analisamos com profundidade quatro composições de Osvaldo Lacerda: Automação, Romaria, A Primeira Missa e o Papagaio e o movimento Uníssono da obra Quatro Estudos para Coro. As obras analisadas foram performatizadas durante o período de doutorado junto ao Coro de Câmara Comunicantus e pudemos formar, experimentar e consolidar nossas concepções interpretativas, as quais comentamos e justificamos ao longo do texto. Por fim, apontamos para algumas respostas sobre o espaço criativo na performance de uma obra extremamente indicativa e sobre a responsabilidade do intérprete diante da partitura. This thesis is part of the doctoral work in Musical Performance with specialization in Choral Conducting for the Post-Graduation Program in Music of the Escola de Comunicações e Artes da Universidade de São Paulo. During the four doctoral years, concerts, rehearsals and practices were undertaken simultaneously with the writing of this text which discusses questions regarding the practice of a performer. Our main object is the relationship between musical writing and performance. As interpreters, we seek to understand what the creative spaces and their limits within a work of music are. In order to do this, the choral work of the Brazilian composer Osvaldo Lacerda - known for his rigorous and rather indicative writing - was used. After a reflection on the conflicts between composition and interpretation, a general critical analysis of the compositional writing of Lacerda was carried out to identify the spaces for the creativity of the interpreter. Next, an in-depth analysis was carried out on four compositions by Osvaldo Lacerda: Automação, Romaria, and O Papagaio and the movement Uníssono of the work Quatro Estudos para Coro. The analyzed works were presented during the doctoral period together with the Chamber Choir Comunicantus and we could form, test and consolidate our interpretative conceptualizations, as is commented and justified throughout the text. Lastly, we point to some answers regarding the creative space in the performance of an extremely indicative piece and about the responsibility of the interpreter to the sheet music.

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Andigué, Job. "Mise en place d'un système d'information géographique comme base d'une stratégie pour une meilleure gestion des espaces ruraux : cas du canton de Bongor rural au sud-ouest du Tchad." Paris 1, 1999. http://www.theses.fr/1999PA010638.

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Le souci de mieux gérer les ressources naturelles existantes dans la + zone de concentration ; du fonds européen du développement (FED), un espace géographique vaste de 31 000 km2, incluant le chari, le logone et les rives sud du lac-Tchad dans le bassin tchadien, a conduit à la mise en place d'un système d'information géographique (SIG) fonctionnel. Le canton de Bongor rural a été choisi comme site-test. Ce premier objectif est atteint grâce à l'application d'une méthode originale, développée pour traiter 11 thèmes nécessaires à la constitution de la base de données géographique relationnelle. Le croisement des cartes thématiques issues du traitement des photographies aériennes de 1974 et d'une image HRV spot de 1994, a apporté des connaissances nouvelles, plus précises de l'évolution du milieu naturel en vingt ans. Ces documents servent en outre, de référentiels géographiques indispensables au SIG. Une connexion entre géo concept et Access, deux logiciels de base utilises, autorise au travers des liens identifies, l'accès aux informations intégrées de part et d'autres. Cette expérience menée en grandeur réelle peut s'appliquer à d'autres espaces ruraux. Pour cela, des nouvelles propositions qui visent à garantir la fiabilité des informations à gérer sont exprimées The objective to better manage the natural resources existing in the extension command area of the european development fund (edf), located in the Chad basin and comprising a territory of 31 000 km2 with two rivers, the chari and the logone, and the southern banks of the Chad lake, has led us to develop a geographical information system (gis). The locality of bongor has been chosen as a pilot area for this project. The above mentioned objective has been reached due to the application of an original method which has been developed to deal with the eleventh themes necessary to build the geographical data base of the gis. The crossing of thematic maps elaborated on the basis of an analysis of aerial photographs taken in 1974 and of a spot image hrv in 1994 has given new and more accurate information, on the evolution of the natural environment of this area in the past twenty years. Theses documents created with two programs being connected, it was therefore possible to access and use the information stocked in the both. This experiment tested on a large geographical scale can be applied to other rural areas. To ensure the good elaboration and use of such an geographical information, some new propositions have been suggested

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Bana, Émilie. "Inhibition des phosphatases CDC 25 dans le cadre d'une thérapie anticancéreuse : étude mécanistique de nouveaux inhibiteurs." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0105/document.

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Dans le cadre de la recherche de nouvelles cibles pour le traitement du cancer, les phosphatases Cdc25 sont des candidats intéressants dont l'inhibition devrait permettre de ralentir la croissance tumorale et éventuellement d'améliorer les traitements actuellement en usage. Les objectifs de ce projet de thèse sont de concevoir et synthétiser de nouveaux composés capables d'inhiber les CDC25, et de déterminer l'efficacité des meilleurs composés dans les lignées cellulaires du cancer du sein. L'évaluation du potentiel inhibiteur des composés est réalisée in vitro par une méthode fluorimétrique très sensibilité (substrat 3-OMFP). Les effets des composés sont évalués dans les lignées cellulaires MCF-7 et MDA-MB-231 : La viabilité des cellules est évaluée par la méthode colorimétrique du MTT, la cytotoxicité est évaluée par coloration au bleu trypan et par observation microscopique avec le système de vidéomicroscopie Incucyte. La mort cellulaire est caractérisée par la détection de marqueurs apoptotiques (caspases) et de marqueurs des dommages de l'ADN (H.2AX Histone PARP) par western blot. L'analyses des mécanismes liés à la mort cellulaire sont explorées par cytométrie en flux via la détection d'espèces réactives de l'oxygène (ERO) avec les sondes H2DCFDA et Redox Sensor Red. L'inhibition de CDC25 dans les cellules est évaluée indirectement par détection des formes phosphorylées dse CDK en Western Blot. L'évaluation in vitro de 93 molécules synthétisées nous a permis d'identifier de nouveaux composés actifs. Ils appartiennent à diverses familles chimiques comprenant des stéroïdes, thiophènes, coumarines, imidazoles ainsi que des dérivés de quinone. Les dérivés coumariniques ont montré une intéressante inhibition de CDC25, non décrite jusqu'à présent. Une nouvelle structure coumarine-soufre-quinone, nommée SV37, a été conçue pour optimiser le potentiel d'inhibition. Ce composé présente un fort potentiel inhibiteur des CDC25 in vitro (CI50 < 5uM pour CDC25 A et C). L'effet de SV37 sur la croissance cellulaire a été évalué sur les lignées cellulaires MCF-7, MDA-MB-231, hTERT-HME1 et HepG2 sur lesquelles une inhibition de la croissance cellulaire est observée (CI50 de 9 à 18 µM). L'analyse de la viabilité des cellules traitées à la CI50 indique l'absence de mort cellulaire pour la lignée MCF7, tandis que pour la lignée MDA-MB-231 la diminution de la croissance cellulaire est liée à une augmentation de la mort cellulaire. Afin d'étudier les mécanismes liés à la mort cellulaire, nous nous sommes concentrés sur l'étude du modèle triple négatif MDA-MB- 231. Les modifications morphologiques de ces cellules sont caractérisées par l'apparition d'altérations cellulaires compatibles avec la mort cellulaire. Le clivage des caspase-3 et 7 a été observé dès 16h de traitement, ce qui suggère l'induction d'une mort apoptotique. Par ailleurs, des ERO ont été détectées 15 min après le début du traitement, cette émission d'ERO a pu être totalement bloquée par un prétraitement avec la N-acétylcystéine (NAC). La détection de marqueurs des dommages de l'ADN, entre 16 et 28 heures après début du traitement, corrobore l'activation des caspases et les observations réalisées en vidéo-microscopie. Après traitement à CI50, une accumulation des pCDK dans les cellules a été observée après 4 et 8 heures, suggérant une inhibition de l'activité CDC25. De plus, les cellules prétraitées avec la NAC n'ont montré aucune accumulation de pCDK après traitement par SV37. Ces résultats suggèrent un lien direct entre la production de ROS induit par le composé SV37 et l'inhibition des CDC25. Ce projet a permis de définir les coumarines en tant que nouvelle classe de composés inhibitrice des phosphatases CDC25. Ces travaux ont de plus permis l'identification d'un composé coumarine-soufre-quinone SV37 qui constitue une structure de base pour le développement d'inhibiteurs de plus en plus efficaces, Within the context of research for new targets for cancer therapy, Cdc25 phosphatases are interesting candidates, the inhibition of which being able to slow down tumor growth and eventually improve the cancer treatments currently in use. The objectives of this PhD project are to design and synthesize new compounds able to inhibit CDC25 and to determine efficiency of identified compounds in breast cancer cell lines. In vitro evaluation of inhibitory potential of compound is realized through a high sensitivity fluorometric method (3-OMFP substrate). Cellular effects were evaluated in MCF-7 and MDA-MB-231 cell lines. Effects on cell viability are assessed through MTT assays, and cytotoxicity is evaluated through trypan blue assays and microscopic observations with Incucyte videomicroscopy system. Cell death was characterized by detection of apoptotic markers (caspases) and DNA damages markers (PARP Histone H.2AX) by Western Blotting. The analyses of mechanisms underlying cell death were explored through cytometric detection of reactive oxygen species (ROS) with H2DCFDA and Redox Sensor Red probes. Inhibition of CDC25 in cells was indirectly evaluated through detection of phosphorylated forms of CDK by Western Blotting. In vitro evaluation of 93 synthesized compounds allowed us to find new active compound in various chemical families including steroid, thiophene, coumarinic, imidazole and quinone derivatives. The coumarinic derivatives showed potent CDC25 inhibition. A new coumarin-sulfurquinone combined structure, named SV37, was designed to optimize efficiency of inhibition. In vitro tests on this compound, showed a strong CDC25 inhibitory potential (IC50 under 5µM for CDC25 A and C). Effect of SV37 on cell growth was evaluated on various cell lines (MCF-7, MDA-MB-231, hTERT-HME1 and HepG2). Results indicate inhibition of cell growth (IC50 values from 9 to 18 µM). Analysis of cell viability indicates no remarkable cell death in MCF7 at IC50 value whereas in MDA-MB-231 the cell growth decrease was characterized by an increase of cell death. For deeper investigations on the cell death and on the underlying mechanisms, we focused the study on the triple negative model MDA-MB-231. The morphological changes of MDA-MB-231 cells during the treatment were characterized by the appearance of cellular alterations compatible with a cellular demise and culminating with a disruption of cells after 20h. Caspase-3 and 7 cleavages were observed 16h after beginning of the treatment, suggesting an apoptotic cell death. A ROS induction was observed 15 min after the beginning of the treatment and was totally prevented by Nacetylcysteine (NAC) pretreatment. DNA damage markers were detected between 16 and 28 hours after beginning of treatment, a timing falling with caspase activation and with the appearance of cell demise observed by video microscopy. Accumulation of pCDK in cells was observed after 4 and 8 hr of treatment by SV37 at IC50 suggesting an inhibition of CDC25 activity, and cells pretreated with NAC showed no accumulation of pCDK after SV37 treatment. This strongly suggests a direct link between ROS generation by the compound SV37 and the accumulation of pCDK. This project increased knowledge on inhibitors of CDC25 phosphatases and allowed the identification of coumarine compound as new CDC25 inhibitors. This work will enable the development of ever more efficient inhibitors, leading to efficient inhibition of CDC25 and inhibition of tumor development

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Niocel, Mathilde. "Caractérisation des fonctions cellulaires du facteur de restriction viral APOBEC3A." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN017/document.

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APOBEC3A (Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like editing complex 3 A) appartient à la famille des cytidines désaminases, qui clivent les cytidines en uraciles. APOBEC3G (le modèle de la famille) est un facteur de restriction du VIH : son incorporation dans la particule virale lui permet de désaminer le génome viral néoformé, entrainant hypermutations et dégradation de l’ADN viral. A3A, au contraire, n’est pas incorporée dans la particule virale : la protéine, exprimée spécifiquement dans les cellules myéloïdes de façon inoffensive pour la cellule, agit de la même façon qu’A3G en s’attaquant au virus dès son entrée dans la cellule.Physiologiquement, dans les cellules non-myéloïdes, les APOBEC3 désaminent l’ADN cellulaire simple brin, dont les uraciles sont retirés par UNG2. Les sites abasiques sont clivés par la machinerie de réparation de l’ADN, conduisant parfois à des cassures double-brin et à la mort de la cellule.L’objectif de la thèse était de comprendre cette différence de comportement selon le type cellulaire. Pour cela, des lignées cellulaires inductibles pour A3A ont été créées en cellules HeLa et U937 (monocytaire). Les données obtenues indiquent qu’A3A, partiellement nucléaire, édite l’ADN des cellules en division, conduisant à des dommages à l’ADN, à la production d’espèces réactives de l’oxygène (ROS) et à la mort des cellules. Les cellules différenciées ne présentent pas ce type de dommages, et cela s’explique par une localisation différente de la protéine. Ces résultats permettent de faire pour la première fois le lien entre dommages à l’ADN induits par un membre de la famille des A3 et production de ROS, et donc à l’induction d’une activation immunitaire. Cette activation pourrait avoir des implications dans l’infection ainsi que dans les processus tumorigéniques APOBEC3A (Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like editing complex 3 A) belongs to a family of cytidine deaminases that can edit cytidines to uraciles. APOBEC3G (model protein for the family) is a restriction factor for HIV: since it’s incorporated in the viral particle, it can deaminate the newly formed viral genome leading to hypermutation and viral DNA degradation.A3A is not incorporated in the viral particle: this protein is specifically expressed in myeloid cells where it is harmless for the cell and edits the DNA of the incoming viral particle in the same way than A3G.Physiologically, in non-myeloid cells, APOBEC3s deaminate single strand cellular DNA and the resulting uraciles are cut out by UNG2. These abasic sites are cleaved by the DNA repair machinery and can generate double strand breaks that will result in cell death.The objective of the thesis was to understand this difference of behaviour between different cell types. For that purpose, A3A-inducible cell lines were created in HeLa and U937 (monocytic) cells. The results obtained indicate that partially nuclear A3A edits the genomic DNA of cycling cells, leading to DNA damage, to the production of reactive oxygen species (ROS) and to cell death. Differentiated cells do not present this type of damage and that phenotype can be explained by a different localization of the protein.These results link for the first time DNA damage induced by a member of the A3 proteins family to ROS production and to induction of an immune activation. This activation could have implications in infection as well as in tumorigenic processes

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Lima, Renato Ribeiro de. "Modelagem espaço-temporal para dados de incidência de doenças em plantas." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-23052005-164227/.

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A informação sobre a dinâmica espaço-temporal de doenças de plantas é de importância fundamental em estudos epidemiológicos, podendo ser utilizada para descrever e entender o desenvolvimento das doenças, desenvolver planos de amostragem, planejar experimentos controlados e caracterizar perdas na produção ocasionadas pela doença. O estudo de padrões espaciais de doenças de plantas, que são reflexos do processo de dispersão dos patógenos, é importante em estudos epidemiológicos, como o de doenças dos citros, para se definirem estratégias mais adequadas para o controle das doenças, diminuindo os prejuízos causados. A Citricultura é uma das principais atividades agrícolas do Brasil e representa a principal atividade econômica de mais de 400 municípios do Triângulo Mineiro e do Estado de São Paulo, onde se encontra a maior área de citros do país e a maior região produtora de laranjas do mundo. Na avaliação do padrão espacial, diferentes métodos têm sido utilizados, dentre os quais incluem-se o ajuste de distribuições, como, por exemplo, a distribuição beta-binomial, o estudo da relação variância-média, o cálculo de correlação ao intraclasse, a utilização de técnicas de autocorrelação espacial, métodos de classes de distâncias e o ajuste de modelos estocásticos espaço-temporais. Diante da importância de se estudarem padrões espaciais da incidência de doenças em plantas e da necessidade de se conhecer melhor a epidemiologia da morte súbita dos citros e do cancro cítrico, uma técnica baseada em verossimilhança para o ajuste de modelos estocásticos espaço-temporais foi utilizada na caracterização de padrões espaciais. Modificações na metodologia original, buscando uma diminuição do tempo gasto nas análises, foram propostas nesse estudo. Os resultados mostram que as modificações propostas resultaram em uma diminuição significativa no tempo de análise, sem perda de acurácia na estimação dos parâmetros dos modelos considerados. The information about the spatial-temporal dynamics is of fundamental importance in epidemiological studies for describing and understanding the development of diseases, for developing efficient sampling plans, for planning controlled experiments, for evaluating the effect of different treatments, and for determining crop losses. The Citriculture is the major economic activity of more than 400 municipalities in Minas Gerais and São Paulo States. This is the largest citrus area in Brazil, and the largest sweet orange production area in the world. Therefore, it is very important to study and to characterize spatial patterns of plant diseases, such as citrus canker and citrus sudden death. In the spatial dynamics study, many different methods have been used to characterize the spatial aggregation. These include the fitting of distributions, such as the beta-binomial distribution, the study of variance-mean relationships, the calculation of intraclass correlation, the use of spatial autocorrelation techniques, distance class methods and, the fitting of continuous time spatiotemporal stochastic models. In this work, an improved technique for fitting models to the spatial incidence data by using MCMC methods is proposed. This improved technique, which is used to investigate the spatial patterns of plant disease incidence, is considerably faster than Gibsons methodology, in terms of computational time, without any loss of accuracy.

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Brown, Ahumada Carolina. "El Poema de Fernán Gonzáles y el Cantar de Roldán: La ‘mala imagen’ del moro en la épica española y francesa." Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/110271.

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Informe de Seminario para optar al grado de Licenciado en Lengua y Literatura Hispánica mención Literatura. Seminario de grado: Desde la escritura: imágenes y representaciones del Islam y los musulmanes El Poema de Fernán González y El Cantar de Roldán: La ‘mala imagen’ del moro en la épica española y francesa, consiste en la revisión de dos famosos poemas épicos: El Cantar de Roldán y el Poema de Fernán González, textos canónicos de la literatura medieval. Esta investigación se centrará en el estudio de la manera en que los personajes ‘moros’ o ‘sarracenos’ son representados en estas obras, tomando en cuenta tanto sus características físicas como morales y sicológicas. Asimismo, se tendrá en especial consideración la caracterización de su religión.

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Paviot, Arnaud. "La guitare flamenca de 1920 à nos jours." Thesis, Tours, 2017. http://www.theses.fr/2017TOUR2033/document.

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Dans l’imaginaire comme dans la pratique, la guitare et le flamenco sont indissociables. Cette alliance dure depuis plus d’un siècle et demi. Depuis le creuset andalou, le flamenco s’est peu à peu formé. D’abord art festif des fêtes privées, il est sorti de ce cadre pour trouver d’autres lieux de représentation. Ce furent les cafés-cantantes, puis les concours, puis les opéras-flamencos. Il fût parfois l’objet de controverses et de débats entre les défenseurs de la modernité et ceux de la tradition. Le flamenco est une musique immédiatement identifiable pour un auditeur profane. Il est pourtant constitué d’un nombre important de formes et de familles de formes. L’objet de cette étude est de montrer les récurrences dans les formes - les palos- afin de pouvoir identifier la forme par l’analyse rythmique, littéraire et musicale, et en particulier en se basant sur le jeu de guitare In imaginary as well than in practice, guitar and flamenco music are inseparable . This alliance last for more than a century and half. From the Andalusian melting pot, flamenco has little by little formed himself. At first festive art from private parties, he went out to find new places of representation. That was the cafés-cantantes, then the competitions, then the opéras-flamencos. He was sometimes the object of controversy and of debates between defenders of modernity and tradition. Flamenco is an immediately identifiable music for a profane auditor. But he is constituted of an important numbers or forms or of form family. This study object is to show recurrences in the forms – the palos – to be able to identify the form by rhythmical, literary and musical analysis, particularly basing itself on the guitar playing

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Sáez, Rosenkranz Isidora. "Movimiento populares, siglos XIX y XX. "Soy campesino y soy cantor", la fiesta de la Cruz de Mayo, un espacio de sociabilidad y conformación de identidad campesina, aculeo 1960-2005." Tesis, Universidad de Chile, 2005. http://repositorio.uchile.cl/handle/2250/110191.

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Tumura, Karina Goulart [UNESP]. "Dinâmica espaço-temporal, quantificação de danos e perdas e influência do cancro (Chrysoporthe cubensis) no acúmulo de biomassa e fixação de carbono em seis genótipos de eucalyptus spp." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/145519.

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Made available in DSpace on 2016-12-09T13:52:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-30. Added 1 bitstream(s) on 2016-12-09T13:55:27Z : No. of bitstreams: 1 000872895.pdf: 2530449 bytes, checksum: b7b0839ed7ed72df3a453cac568f274c (MD5) A cultura do eucalipto é uma das mais importantes do Brasil, constituindo-se em fonte de energia e madeira renovável, suportando importantes processos agroindustriais, dentre eles, a produção de celulose, papel e essências. O eucalipto, como outras espécies vegetais, é infectado por diversos patógenos, principalmente fungos, desde o viveiro até plantios adultos. Neste trabalho, será estudado o agente causador do cancro basal, Chrysoporthe cubensis. Esta doença possui ampla distribuição geográfica, ocorrendo desde o extremo sul do Estado de São Paulo até a Amazônia, observando-se prejuízos em regiões de baixa altitude de Espírito Santo, do Vale do rio Doce em Minas Gerais e Recôncavo Baiano. Sua sintomatologia é bastante variada, podendo atacar plantas de cinco meses de idade até o final da rotação. As plantas jovens, por apresentarem diâmetros reduzidos, podem ser aneladas na sua base pelo cancro, sendo levadas à morte. Do ataque em plantas mais velhas resultam lesões com pouco ou abundante trincamento até cancros típicos, podendo ser encontrados a diversas alturas do tronco. O local escolhido para a realização do trabalho, foi a área do projeto EUCFLUX, onde estão implantadas parcelas experimentais com 16 materiais genéticos, em diferentes condições de solo e altitude. Os estudos sobre a influência de doenças no acúmulo de biomassa e fixação de carbono são escassos, sendo assim, os objetivos desse trabalho foram: a) verificar a suscetibilidade ao cancro basal dos seis clones com maior produtividade utilizados nas parcelas experimentais do EUCFLUX; b) proceder o estudo espaço-temporal da doença e c) verificar a influência do cancro basal no acúmulo de biomassa e fixação de carbono das plantas atacadas. Foram avaliadas três repetições quanto à incidência da doença, sendo que tais dados formaram a base para a análise espaço-temporal... Eucalyptus' culture is one of the most important in Brazil being a source of renewable energy and wood. In addition, it supports important agro-industrial processes for the production of pulp, paper and essences. Eucalyptus, like any other plant species, can be infected by many pathogens, especially fungi, from nurseries to adult plantations. In this work, the causal agent of basal canker, Chrysoporthe cubensis, were studied. This disease has a wide geographical distribution, occurring from the southern end of São Paulo State to the Amazon, observing sensitive damages in low-lying regions of Espírito Santo State, Rio Doce Valley in Minas Gerais State and Reconcavo Baiano. Its symptons are quite varied and the fungi can attack plants from five months of age until the end of forest rotation. Young plants with small diameters may be girdled at their base by canker, being put to death. Attack in older plants may result in low or heavy typical cankers, that can be found at different heights of the trunk. The work was conducted in the area of EUCFLUX project, which were established with 16 clones in 10 experimental plots with different soil conditions and elevation. Studies of disease influence in carbon fixation and biomass accumulation are scarce, therefore, the objectives of this work were: a) verify the susceptibility to basal canker of the six clones with higher productivity used in experimental plots of EUCFLUX; b) conduct the spatiotemporal study of the disease and; c) verify the influence of basal canker in the accumulation of biomass and carbon fixation of the attacked plants. Incidence of the disease were evaluated in three plots and these data were the basis for spatiotemporal analysis. To determine biomass parameters, inventory was done in the same three plots and volume and biomass equations were adjusted. In addition, specific gravity of the wood and bark were calculated to healthy ...

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Tumura, Karina Goulart 1983. "Dinâmica espaço-temporal, quantificação de danos e perdas e influência do cancro (Chrysoporthe cubensis) no acúmulo de biomassa e fixação de carbono em seis genótipos de eucalyptus spp. /." Botucatu, 2015. http://hdl.handle.net/11449/145519.

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Orientador: Edson Luiz Furtado Banca: Martha Maria Passador Banca: Christiane Ceriani Aparecido Banca: Luiz Alberto Blanco Jorge Banca: Waldir Cintra de Jesus Junior Resumo: A cultura do eucalipto é uma das mais importantes do Brasil, constituindo-se em fonte de energia e madeira renovável, suportando importantes processos agroindustriais, dentre eles, a produção de celulose, papel e essências. O eucalipto, como outras espécies vegetais, é infectado por diversos patógenos, principalmente fungos, desde o viveiro até plantios adultos. Neste trabalho, será estudado o agente causador do cancro basal, Chrysoporthe cubensis. Esta doença possui ampla distribuição geográfica, ocorrendo desde o extremo sul do Estado de São Paulo até a Amazônia, observando-se prejuízos em regiões de baixa altitude de Espírito Santo, do Vale do rio Doce em Minas Gerais e Recôncavo Baiano. Sua sintomatologia é bastante variada, podendo atacar plantas de cinco meses de idade até o final da rotação. As plantas jovens, por apresentarem diâmetros reduzidos, podem ser aneladas na sua base pelo cancro, sendo levadas à morte. Do ataque em plantas mais velhas resultam lesões com pouco ou abundante trincamento até cancros típicos, podendo ser encontrados a diversas alturas do tronco. O local escolhido para a realização do trabalho, foi a área do projeto EUCFLUX, onde estão implantadas parcelas experimentais com 16 materiais genéticos, em diferentes condições de solo e altitude. Os estudos sobre a influência de doenças no acúmulo de biomassa e fixação de carbono são escassos, sendo assim, os objetivos desse trabalho foram: a) verificar a suscetibilidade ao cancro basal dos seis clones com maior produtividade utilizados nas parcelas experimentais do EUCFLUX; b) proceder o estudo espaço-temporal da doença e c) verificar a influência do cancro basal no acúmulo de biomassa e fixação de carbono das plantas atacadas. Foram avaliadas três repetições quanto à incidência da doença, sendo que tais dados formaram a base para a análise espaço-temporal... Abstract: Eucalyptus' culture is one of the most important in Brazil being a source of renewable energy and wood. In addition, it supports important agro-industrial processes for the production of pulp, paper and essences. Eucalyptus, like any other plant species, can be infected by many pathogens, especially fungi, from nurseries to adult plantations. In this work, the causal agent of basal canker, Chrysoporthe cubensis, were studied. This disease has a wide geographical distribution, occurring from the southern end of São Paulo State to the Amazon, observing sensitive damages in low-lying regions of Espírito Santo State, Rio Doce Valley in Minas Gerais State and Reconcavo Baiano. Its symptons are quite varied and the fungi can attack plants from five months of age until the end of forest rotation. Young plants with small diameters may be girdled at their base by canker, being put to death. Attack in older plants may result in low or heavy typical cankers, that can be found at different heights of the trunk. The work was conducted in the area of EUCFLUX project, which were established with 16 clones in 10 experimental plots with different soil conditions and elevation. Studies of disease influence in carbon fixation and biomass accumulation are scarce, therefore, the objectives of this work were: a) verify the susceptibility to basal canker of the six clones with higher productivity used in experimental plots of EUCFLUX; b) conduct the spatiotemporal study of the disease and; c) verify the influence of basal canker in the accumulation of biomass and carbon fixation of the attacked plants. Incidence of the disease were evaluated in three plots and these data were the basis for spatiotemporal analysis. To determine biomass parameters, inventory was done in the same three plots and volume and biomass equations were adjusted. In addition, specific gravity of the wood and bark were calculated to healthy ... Doutor

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Lavergne, Lucie, and Lucie Lavergne. "L'écriture poétique, d'espaces et de rythmes : regards croisés sur six recueils de la poésie hispanophone contemporaine : Rubén Darío, Cantos de vida y esperanza (1905) ; Juan Ramón Jiménez, Diario de un poeta reciencasado (1916) ; Rafael Alberti, Marinero en tierra (1924) ; Vicente Aleixandre, Espadas como labios (1932) ; Pere Gimferrer, Arde el mar (1966) ; Leopoldo María Panero, Teoría (1973)." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2011. http://tel.archives-ouvertes.fr/tel-00942945.

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Par les analyses croisées de six recueils de la poésie hispanophone du XXe siècle, cette thèse se propose de définir l'écriture poétique à travers son rythme. Ce dernier est envisagé relation avec la notion d'espace. Partant de l'association traditionnelle du rythme et de la métrique, la première partie observe comment l'espace métrique de l'écriture versifiée, par sa structure, ses frontières, met en jeu la loi et sa transgression. En revanche, la seconde partie considère l'espace comme " substance ", c'est-à-dire qu'elle observe l'écriture dans son déroulement même, d'abord langagier et phrastique. Centrée sur la figure de la ligne, cette seconde conception du rythme implique également la temporalité, contenue dans les mots (les verbes), et engendrée par l'agencement des phrases. Dans les recueils, cependant, la linéarité est parfois disloquée par différents phénomènes ayant trait au langage (dissolution de la syntaxe), au vers (enjambements, échelonnement) et à la spatialisation. Le dernier chapitre de la seconde partie est donc consacré à la visibilité de l'écriture sur la page. Cette dernière, corps de l'écriture, révèle dans le poème le corps de l'écrivant. C'est sur le sujet et ses différents visages et représentations que se centre notre dernière partie. Le rythme apparaît, enfin, comme une mosaïque d'espaces du discours et d'espaces de sens (et d'images) qui implique tout autant le locuteur que le lecteur.

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Blein, Sophie. "Étude de la variabilité du génome mitochondrial comme facteur de susceptibilité au cancer du sein." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10240/document.

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Une large part de la composante génétique du risque de cancer du sein est encore inexpliquée. J'ai ainsi étudié dans quelle mesure les variants observés sur le génome mitochondrial pourraient en partie expliquer ce risque. En effet la mitochondrie, en tant que source d'énergie cellulaire, est un organite impliqué dans la synthèse des espèces oxygénées réactives ou radicaux libres, éléments contribuant à l'instabilité génomique et au développement tumoral. Un premier axe de recherche m'a conduit à étudier une interaction potentielle entre des variants du génome mitochondrial et du génome nucléaire, en conjonction avec la consommation d'alcool. J'ai ensuite analysé les haplogroupes mitochondriaux peuvent être considérés en tant que potentiels modificateurs de l'association entre le risque de cancer du sein et les mutations causales portées par les gènes BRCA1 et BRCA2. L'haplogroupe T1a1 a été identifié comme modificateur du risque conféré par les mutations pathogènes localisées sur le gène BRCA2. Enfin, j'ai caractérisé par séquençage à haut débit le génome mitochondrial de 436 femmes ayant un cancer du sein et de forts antécédents familiaux, mais n'étant porteuses d'aucune mutation causale sur BRCA1 et BRCA2. Plusieurs variants ont été prédits comme dommageables. Deux gènes en particulier MT-ATP6 et MT-CYB, sont spécifiquement enrichis à la fois en nombre de variants portés, et de par le nombre d'individus porteurs de ces variants dans notre étude. L'ensemble du travail réalisé a ainsi contribué à enrichir les connaissances sur les potentielles associations entre les variations du génome mitochondrial et le risque du cancer du sein A large part of the genetic component of breast cancer risk (BCR) is still unexplained. Therefore I studied if variants of the mitochondrial genome (mtDNA) might explain a part of this risk. In fact, mitochondria is the main source of reactive oxygen species (ROS), which contribute to genomic instability and tumor development. As a first axis of research, I studied potential interactions between some nuclear and mitochondrial variants, in conjugation to alcohol consumption. Despite the large dimensions of our dataset, the lack of statistical significant interaction in our data might reveal that former published results that show such interactions were not robust. I also studied if mitochondrial haplogroups could be considered as modificators of known association between BCR and pathogenic mutations in the BRCA1/2 genes. I identified haplogroup T1a1 such as modificator for individuals carrying a mutated BRCA2. Finally, I characterized by NGS mitochondrial genome of women diagnosed for a familial breast cancer, but tested negative for known pathogenic BRCA1/2 mutations. Several variants were identified as potentially damaging. Two genes, MT-ATP6 and MT-CYB are specifically enriched both in terms of distinct variants and in the number of individuals carrying these variants. They are both essential structural components of the mitochondrial respiratory chain, the main ROS production source in the cell. All these analyses contribute to enrich the knowledge about associations between BCR and variability of mtDNA, by integrating questions linked to interactions between genomic variants, environmental exposure, and effect modifications related to mitochondrial haplogroups

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Lu, Cong. "Analyse microélectrochimique du stress oxydant à l'échelle de la cellule unique : application aux cellules cancéreuses du sein." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00828217.

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Les quantités et flux infinitésimaux de biomolécules électroactives émises par une cellule unique isolée en boite de Pétri peuvent être mesurés en temps réel par une ultramicroélectrode placée au contact de la cellule sécrétrice. Le travail présenté dans ce manuscrit a pour but d'étendre cette méthodologie analytique d'utilisation des microélectrodes de carbone platiné à l'étude du lien entre stress oxydant et l'effet de substances anti-cancéreuses (FcdiOH, DP1 et Fc-OH-TAM) sur des cellules tumorales du sein. Le signal ampérométrique est collecté par une microélectrode de carbone platiné positionnée à une centaine de nanomètres au-dessus d'une cellule tumorale du sein et incubée en présence d'espèces anticancéreuses de type ferrocifènes. La libération in situ des espèces réactives de l'oxygène (ROS) et de l'azote (RNS), i.e., H2O2, ONOO-, NO et NO2-, par ces cellules (MCF7 et MDA-MB-231) est analysée. Les études morphologiques montrent que les produits FcdiOH, DP1 et Fc-OH-TAM présentent un effet anti-prolifératif significatif. Le traitement avec Fc-diOH et surtout DP1 augmente significativement la production de ROS. Par contre, Fc (témoin) et Fc-OH-TAM n'ont pas ou très peu d'effet. Cela est assez surprenant pour Fc-OH-TAM, qui a l'effet anti-prolifératif le plus fort parmi les ferrocifènes testés. Fc-diOH et DP1, quant à eux, semblent induire une surproduction de NO° et/ou de NO2-, ainsi que du peroxyde d'hydrogène. Cette comparaison inédite entre études morphologiques et électrochimiques tend à montrer que les ferrocifènes agissent par deux voies qui sont complémentaires, soit via la formation de quinone méthide (Fc-OH-TAM), soit par réaction directe (DP1, Fc-diOH).

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Assi, Mohamad. "L'impact de l'activité physique et des antioxydants sur le dialogue entre la tumeur et le muscle squelettique dans le cancer : déchiffrage de voies de signalisation impliquées dans la croissance de la tumeur et l'atrophie musculaire." Thesis, Rennes 2, 2016. http://www.theses.fr/2016REN20055/document.

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Les espèces réactives de l’oxygène (ERO) contrôlent plusieurs aspects de la carcinogenèse, étant donné leur capacité àpromouvoir la prolifération mais aussi à induire la sénescence et l’apoptose. Dans les stades avancés de cancer, les EROpeuvent également participer au développement de l’atrophie musculaire, engendrant une détérioration de la qualité de viedes patients. L’activité physique (AP), connue pour augmenter les défenses antioxydants de l’organisme et lasupplémentation en antioxydants sont considérées comme deux stratégies susceptibles de moduler la croissance tumorale, d’améliorer la performance physique et de réduire les effets secondaires liés à la maladie et aux traitements anticancéreux. Néanmoins, plusieurs questions restent aujourd’hui sans réponse. En effet, bien que l’AP puisse réduire la progression du cancer du sein, du colon et de la prostate, son impact sur les cancers se développant au sein du muscle (ex : le liposarcome), donc soumis aux contractions musculaires répétées, reste méconnu. En utilisant des approches in vivo et in vitro, nous avons démontré que maintenir une AP régulière accélère la croissance du liposarcome intramusculaire, probablement, via la réduction des taux circulants d’insuline et l’inhibition de la voie « P38 MAPK-P21 ». Pour les patients ne pouvant pas pratiquer d’AP, la consommation d’antioxydants pourrait être un moyen de réduire les ERO tumorales et musculaires et ainsi être prometteuse. Toutefois, les études actuelles restent très controversées. Nos travaux ont montré dans un modèle murin de cachexie cancéreuse que des doses nutritionnelles d’un produit antioxydant commercialisé en France, étaient suffisantes pour accélérer la croissance de la tumeur colique, favoriser la perte de masse corporelle totale et musculaire et engendrer la mort prématurée des souris. L’ensemble de nos résultats suggère que la pratique d’AP et la consommation en antioxydants peuvent induire des effets différents selon le type de tumeur et leur implantation, nécessitant une prise en charge individualisée des patients. En effet, (1) les patients atteints d’un LS intramusculaire devraient éviter de pratiquer une AP durant la période préopératoire mais ces résultats doivent être confirmés par une étude clinique, (2) les patients avec un stade avancé de cancer devraient être vigilants quant à l’utilisation de suppléments antioxydants ; une telle pratique pouvant avoir des répercussions dangereuses sur leur santé Reactive oxygen species (ROS) control several aspects of carcinogenesis as they can either promote tumor growth andprogression or senescence and apoptosis. In advanced stages of cancer, ROS can also drive the development of other cancerrelated complications like, muscle wasting. Physical activity (PA) and antioxidant supplementation have been proposed as two adjuvant strategies to better control tumor growth, ameliorate performance and alleviate secondary symptoms related to cancer itself or to the heavy anticancer therapies. However, several issues remain to be elucidated. First of all, although PA could reduce colon, breast and prostate cancer growth and progression, its impact remains unknown on orthotopic intramuscular tumors like liposarcoma, which directly affect the musculoskeletal apparatus and reduce physical function. Secondly, given the limitedness of PA application in some advanced stages of cancer, patients may increase their dependency on nutritional and antioxidant complements as an alternative strategy, but such practice has spark a lot of polemic and inconsistent results. In this thesis, we have addressed the effectiveness of PA and antioxidants in two distinct animal models of cancer. Using in vivo and in vitro approaches, we found that voluntary PA accelerated the growth of intramuscular liposarcoma tumors and exacerbated skeletal muscle dysfunction, mainly, by decreasing circulating insulin levels and the subsequent activation of the tumor suppressor pathway “P38 MAPK-P21”. We also demonstrated that nutritional doses of commercial antioxidants enhanced colon tumor growth, total body/skeletal muscle weight loss and caused premature death of mice. Such mechanism was due to selective changes in oxidative damage profiles, which decreased in tumor but increased in skeletal muscle, in a way driving tumor growth and skeletal muscle wasting/dysfunction. Clinically, it seems that (1) patients with intramuscular liposarcoma may, at least, not increase their levels of PA or undergo hospital-supervised exercise program, during the preoperative period; until the confirmation of our findings with clinical data and (2) patients with advanced stages of cancer must be very careful against the use of antioxidants as it could lifethreatening. Accordingly, health agencies in France, Europe and USA prohibit the use of synthetic antioxidant supplements without dietary counseling by a cancer patient’s physician and/or nutritionist

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Julienne, Cloé Mimsy. "Altérations du métabolisme énergétique mitochondrial lors de la cachexie cancéreuse." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR3318/document.

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La cachexie est un syndrome complexe caractérisé par une balance énergétique négative. Le rôle joué par le métabolisme énergétique mitochondrial dans ce syndrome est peu connu. Nos précédents travaux montraient une diminution de la synthèse de l’ATP dans les mitochondries hépatiques en stade de cachexie cancéreuse sévère. Dans ce travail, nous démontrons, in vitro, que l’augmentation de la production d’espèce réactive de l’oxygène et du contenu en cardiolipine dans des mitochondries hépatiques saines, mime partiellement les mécanismes observés lors d’un stade cachexie sévère. Nous observons cependant que l’altération du métabolisme mitochondrial hépatique apparait à un stade tardif du développement de la cachexie. En stade sévère les mitochondries musculaires ne développent pas d’altération de leur efficacité de synthèse d’ATP mais une diminution des leurs capacités oxydatives Cancer cachexia is a composite syndrome, characterized by a negative energetic balance. The role played by mitochondrial energetic metabolism in this syndrome is poor known. Our past work showed a decrease of ATP synthesis efficiency in hepatic mitochondria in severe state of cancer cachexia. In this work, we demonstrate, in vitro, that increase of reactive oxygen species and cardiolipine content, in healthy mitochondria, can partly mimic the mechanisms observed in severe state of cancer cachexia. We observe that alteration of hepatic mitochondrial metabolism appear last during the development of cancer cachexia. In sever state of cancer cachexia, skeletal muscle mitochondria don’t develop this alteration but demonstrated a decrease of oxidative capacities

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Loiseau, Philippe. "Etude structurale et geostatistique des gneiss de la region du cezallier : modelisation tridimensionnelle de reseaux de fractures, application a l'ecoulement des fluides." Orléans, 1987. http://www.theses.fr/1987ORLE2055.

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L'etat de fracturation d'un massif cristallin par l'intermediaire de la modelisation est apprehende et passe par des etapes d'acquisition des donnees qui se font en surface et en profondeur, ainsi que par des etapes d'analyse suivant le parametre choisi. L'hydrogeologie des milieux fissures et l'une des applications aux modelisations de champs de fracture. On peut ainsi mettre en evidence un comportement discontinu du flux

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Montanha, Dionize. "Análise espacial e temporal do câncer de mama na região metropolitana da Baixada Santista e sua relação com áreas contaminadas." Universidade Católica de Santos, 2017. http://biblioteca.unisantos.br:8181/handle/tede/3901.

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Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2017-08-22T17:16:27Z No. of bitstreams: 1 Dionize Montanha.pdf: 3874925 bytes, checksum: 5c564d4d796cab82f040686e592599c4 (MD5) Made available in DSpace on 2017-08-22T17:16:28Z (GMT). No. of bitstreams: 1 Dionize Montanha.pdf: 3874925 bytes, checksum: 5c564d4d796cab82f040686e592599c4 (MD5) Previous issue date: 2017-06-21 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES Breast cancer defies the world public health mainly by the high incidence and mortality of the disease. The Metropolitan Region of the Santos Area (RMBS) stands out for presenting high levels of mortality of the disease, as well as various environmental contaminants classified as carcinogens. The research has the objective of analyzing the temporal and spatial distribution of breast cancer in the Metropolitan Region of the Santos Area. Methodology: It is a mixed ecological study (spatial and temporal), about the distribution of breast cancer in the cities of RMBS, as well as in the regions exposed to environmental contaminants and regions of the state of Sao Paulo from 2000 to 2011. The population was composed by women at 20 years old or over, and data was provided by Oncocentro Foundation of Sao Paulo (FOSP), and from the contaminated areas, data was obtained from the Environmental Sanitation Technology Company (CETESB). Data about the population at risk was provided by the State System of Data Analysis (SEADE). The total number of breast cancer cases in the years from 2000 to 2011 was 87.354, 830 cases were excluded being: 779 cases of males over 20 years, and 51 cases under the age of 20 years (4 males and 47 females). From the total of 86.524 followed, 3.233 were in RMBS. Annual standardized coefficients of breast cancer were built to each city in RMBS and to each Regional Health Department (DRS) in the state of Sao Paulo. In order to characterize exposure a density indicator of density of contamination per city was built, for the analysis of the correlation between breast cancer and environmental contamination was utilized the correlation of Pearson. The analysis of variables was realized through Statistical Package for the Social Sciences, version 15.0 (SPSS). Through linear regression, a time trend analyses was done, and to that end SPSS and the Statistics or Windows 8.0 were also used. To the Spatial analyzes, four levels of coefficient intervals of breast cancer were created. A sequential cartographic was developed that reveals the distribution and the spatial-temporal evolution of outcome and exposure. Results: The results show that in RMBS the city with the highest levels of breast cancer is the city of Santos. The correlation of Pearson was positive, with r=0.7 and significance level of p=0,036. In the spatial part, the most contaminated areas presented the highest rates of breast cancer, except for the city of Peruíbe, where, despite low environmental containment, numbers showed high rates of the disease. By means of linear regression, the tendency analysis was done in all counties signaling growth of the disease, with exception of Bertioga county where the tendency is the reduction of the disease. When compared the breast cancer rates of RMBS with the DRS of the São Paulo State, certain regions showed much higher rates as: Araraquara, Araçatuba, Barretos, Bauru, Marília, Ribeirão Preto, São José do Rio Preto and Piracicaba, and the last cited region presented the highest levels of breast cancer in the State of São Paulo. This study confirms the hypothesis that environmental contamination interferes with the distribution of breast cancer, and the time trends indicates an increase in the disease in eight of the nine cities in the region. O câncer de mama desafia a saúde pública mundial principalmente pela alta incidência e mortalidade da doença. A Região Metropolitana da Baixada Santista (RMBS) destaca-se por apresentar elevadas taxas de mortalidade da doença, assim como diversos contaminantes ambientais classificados como cancerígenos. A pesquisa tem por objetivo analisar a distribuição temporal e espacial do câncer de mama na Região Metropolitana da Baixada Santista. Metodologia: Trata-se de um estudo ecológico misto (espacial e temporal), sobre a distribuição do câncer de mama nos municípios da RMBS, assim como nas regiões expostas a contaminantes ambientais e regiões do Estado de São Paulo de 2000 a 2011. A população foi composta por mulheres de 20 anos ou mais, e os dados foram fornecidos pela Fundação Oncocentro de São Paulo (FOSP), e das áreas contaminadas, os dados foram obtidos pela Companhia de Tecnologia de Saneamento Ambiental (CETESB). Dados sobre a população em risco foram fornecidos pelo Sistema Estadual de Análise de Dados (SEADE). O total de casos de câncer de mama dos anos de 2000 a 2011 foi de 87.354, foram excluídos 830 casos sendo: 779 casos do sexo masculino maiores de 20 anos, e 51 casos menores de 20 anos (4 masculinos e 47 femininos). Do total de 86.524 utilizados, 3.233 foram na RMBS. Foram construídos coeficientes padronizados anuais de câncer de mama para cada município da RMBS e para cada Departamento Regional de Saúde (DRS) do Estado de São Paulo. Para caracterizar a exposição foi construído um indicador de densidade de contaminação por município, para a análise da correlação entre taxas de câncer de mama e contaminação ambiental foi utilizada a correlação de Pearson. A análise das variáveis foi realizada por intermédio do Statistical Package for the Social Sciences, versão 15.0 (SPSS). Por intermédio da regressão linear, foi feita a análise da tendência temporal, e para isso utilizou-se também o SPSS e o Statistics for Windows 8.0. Para a análise espacial, foram criadas quatro categorias de intervalos de coeficientes de câncer de mama. Foi desenvolvido o sequenciamento cartográfico que revela a distribuição e a evolução espacial-temporal de desfecho e exposição. Resultados: Os resultados mostram que na RMBS o município com taxas mais elevadas de câncer de mama é o município de Santos. A correlação de Pearson apresentou-se positiva, com um r=0.7 e nível de significância de p=0,036. Na parte espacial, as áreas mais contaminadas apresentaram as maiores taxas de câncer de mama, exceto no município de Peruíbe que, apesar do baixo índice de contaminação ambiental, apresentou altas taxas da doença. Por meio da regressão linear, foi feita a análise de tendência em todas as cidades sinalizando aumento da doença, com a exceção da cidade de Bertioga, onde a tendência é a de redução da doença. Quando comparadas as taxas de câncer de mama da RMBS com os DRS do Estado de São Paulo, algumas regiões apresentaram taxas bem superiores como: Araraquara, Araçatuba, Barretos, Bauru, Marília, Ribeirão Preto, São José do Rio Preto e Piracicaba, sendo que a última região citada apresentou as maiores taxas de câncer de mama do Estado de São Paulo. Esse estudo confirma a hipótese de que a contaminação ambiental interfere na distribuição do câncer de mama, e a tendência temporal sinaliza aumento da doença em oito dos nove municípios da região.

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39

Anjos, Cristineide dos. "O familiar acompanhante da criança e a equipe de enfermagem no centro de terapia intensiva pediátrico oncológico: um espaço de interação no cuidado de enfermagem." Universidade Federal Fluminense, 2015. https://app.uff.br/riuff/handle/1/1679.

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Submitted by Fabiana Gonçalves Pinto (benf@ndc.uff.br) on 2016-05-04T17:45:29Z No. of bitstreams: 1 Cristineide dos Anjos.pdf: 2616100 bytes, checksum: e94501195ff76b65226f80d3a2453fdc (MD5) Made available in DSpace on 2016-05-04T17:45:29Z (GMT). No. of bitstreams: 1 Cristineide dos Anjos.pdf: 2616100 bytes, checksum: e94501195ff76b65226f80d3a2453fdc (MD5) Previous issue date: 2015 Mestrado Acadêmico em Ciências do Cuidado em Saúde O estudo teve como objetivo geral analisar os limites e possibilidades da presença do familiar acompanhante no cuidado à criança com câncer no centro de terapia intensivo pediátrico oncológico e como objetivos específicos: descrever o cuidado à criança no centro de terapia intensivo pediátrico oncológico na visão da equipe de enfermagem e do familiar acompanhante; identificar a visão da equipe de enfermagem sobre a presença do familiar acompanhante no centro de terapia intensiva pediátrico oncológico e conhecer como o familiar acompanhante vê sua presença no centro de terapia intensivo pediátrico oncológico. Trata-se de pesquisa de natureza qualitativa, do tipo estudo de caso, realizado no centro de terapia intensiva pediátrico oncológico de um hospital de referência no tratamento de câncer localizado na Cidade do Rio de Janeiro. A produção de dados envolveu as técnicas de observação simples, com registros em diário de campo, e entrevista semiestruturada com 25 membros da equipe de enfermagem e 10 familiares acompanhantes de crianças com câncer internadas no referido centro de terapia intensiva. Após organização e identificação dos dados, estes foram submetidos à análise temática de conteúdo segundo Bardin, emergindo-se as seguintes categorias: O familiar da criança com câncer até a entrada no centro de terapia intensivo pediátrico oncológico e as interações do familiar acompanhante e membros da equipe de enfermagem no cuidado à criança com câncer no Centro de Terapia Intensiva Oncológico. A partir dos depoimentos dos familiares acompanhantes e da equipe de enfermagem constatou-se que no cuidado a criança hospitalizada no CTIP a interação entre ambos favorece sua adaptação ao ambiente, que envolve inúmeros procedimentos e rotinas, demandando suporte emocional e conforto viabilizado pela presença do familiar e conhecimento técnico e científico da equipe de enfermagem. Assim, conclui-se que o centro de terapia intensivo pediátrico oncológico representa um espaço de interação do familiar acompanhante com a equipe de enfermagem no cuidado a criança com câncer, fundamentado na escuta atenta, viabilizada pelo diálogo que possibilita a troca de conhecimentos do familiar da criança com sua experiência, sentimentos e expectativas. Tal processo tem início com o adoecimento e conta com a equipe de enfermagem que tem como meta o cuidado integral à mesma, incluindo suporte e orientações ao familiar da criança, elemento fundamental no seu processo de hospitalização e tratamento. The study aimed to analyze the limits and possibilities of the presence of an accompanying family member in the care of children with cancer in the pediatric oncologic intensive care unit and as specific objectives: to describe the care of children in the pediatric oncologic intensive care unit in the nursing team and companion family member´s point of view; identify the nursing team´s point of view about the presence of an accompanying family member in the pediatric oncologic intensive care unit and to know how the accompanying family member sees his presence in the pediatric oncologic intensive care unit. It´s a qualitative research, a case study, carried out at the pediatric oncologic intensive care unit of a reference hospital in the treatment of cancer located in the city of Rio de Janeiro. The data production involved the simple observation techniques, with records in field diary, and semi-structured interview with 25 members of the nursing team and 10 accompanying family members of hospitalized children with cancer in that intensive therapy unit. After data identification and organization, these were submitted to thematic content analysis according to Bardin, emerging the following categories: the family of the child with cancer to the entrance in the pediatric oncologic intensive care unit and the family member´s interactions and nursing team members in the care for children with cancer in the Oncologic Intensive Care Unit. From the testimonies of the accompanying family members and nursing team we found that in the care of children hospitalized in the CTIP interaction between them favors its adaptation to the environment, involving numerous procedures and routines, requiring emotional support and comfort made possible by the familiar member presence and scientific and technical knowledge of the nursing team. Thus, it is concluded that the pediatric oncologic intensive care unit is an accompanying family member interaction space with the nursing team in care of children with cancer, based on attentive listening, made possible by dialogue that enables the exchange of the knowledge of the family member with his experience, feelings and expectations. This process begins with the illness and has the nursing team that aims to the comprehensive care to it, including support and guidance to the child's family, a key element in the process of hospitalization and treatment.

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40

Homberg, Nicolas. "New models and algorithms for the identification of sncRNA-(snc)RNA interactions intra and across-species/kingdom." Electronic Thesis or Diss., Lyon 1, 2023. http://www.theses.fr/2023LYO10090.

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Les microARNs (miARNs) sont de petit ARNs non codant présents dans tous les eucaryotes qui régulent, positivement ou négativement, l'expression des ARN messagers (ARNms). Les miARNs ont un potentiel important pour de futurs traitements du cancer et d'autres maladies. Les interactions miARN-ARNm dépendent d'une variété de mécanismes complexes, tels que la complémentarité des séquences, l'accessibilité et la conservation. Cette thèse se concentre sur deux de ces mécanismes, à savoir l'accessibilité et la conservation intra-espèce du site d'interaction, en utilisant des données expérimentales de Cross-linking, Ligation And Sequencing of Hybrids (CLASH). Bien que l'accessibilité des sites d'interaction sur les ARNms soit généralement observée, cela n'est pas le cas pour toutes les interactions. La conservation intra-espèce est un mécanisme peu considéré que nous avons étudiée au travers la recherche de motifs conservés dans les ARNms. Bien que les résultats obtenus soient bruités, il est possible de retrouver via ces motifs certains sites d'interaction sur les ARNms MicroRNAs (miRNAs) are non-coding RNAs present in eukaryotes that regulate the expression of messenger RNAs (mRNAs) up or down. These miRNAs have significant potential in future treatment of cancer and other diseases. The miRNA-mRNA interactions are intricate and involve various mechanisms, such as sequence complementarity, accessibility, and conservation. This thesis focuses on two such mechanisms, namely accessibility and intra-species conservation of the site of interaction, using experimental data from Cross-linking, Ligation And Sequencing of Hybrids (CLASH). Although the accessibility of interaction sites on mRNAs is generally observed, it is not consistent for all interactions. Intra-species conservation is a rare feature, which we explore by inferring conserved motifs from mRNA interaction sites. Although the results are noisy, in some specific cases, we manage to retrieve some mRNA interaction sites from the inferred motifs

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41

Ildefonse, Philippe. "Analyse petrologique des alterations premeteoriques et meteoriques de deux roches basaltiques (basalte alcalin de belbex, cantal, et hawaiite de m'bouda, cameroun)." Paris 7, 1987. http://www.theses.fr/1987PA077118.

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Cette analyse permet de definir les parageneses minerales successives de l'alteration. Il est alors possible d'apprehender les mecanismes geochimiques ayant preside a ces alterations, et d'en analyser certaines relations, chronologiques ou causales, qu'ils peuvent presenter entre eux

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42

Lavergne, Lucie. "L’écriture poétique, d’espaces et de rythmes : regards croisés sur six recueils de la poésie hispanophone contemporaine : Rubén Darío, Cantos de vida y esperanza (1905) ; Juan Ramón Jiménez, Diario de un poeta reciencasado (1916) ; Rafael Alberti, Marinero en tierra (1924) ; Vicente Aleixandre, Espadas como labios (1932) ; Pere Gimferrer, Arde el mar (1966) ; Leopoldo María Panero, Teoría (1973)." Thesis, Clermont-Ferrand 2, 2011. http://www.theses.fr/2011CLF20021/document.

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Par les analyses croisées de six recueils de la poésie hispanophone du XXe siècle, cette thèse se propose de définir l’écriture poétique à travers son rythme. Ce dernier est envisagé relation avec la notion d’espace. Partant de l’association traditionnelle du rythme et de la métrique, la première partie observe comment l’espace métrique de l’écriture versifiée, par sa structure, ses frontières, met en jeu la loi et sa transgression. En revanche, la seconde partie considère l’espace comme « substance », c’est-à-dire qu’elle observe l’écriture dans son déroulement même, d’abord langagier et phrastique. Centrée sur la figure de la ligne, cette seconde conception du rythme implique également la temporalité, contenue dans les mots (les verbes), et engendrée par l’agencement des phrases. Dans les recueils, cependant, la linéarité est parfois disloquée par différents phénomènes ayant trait au langage (dissolution de la syntaxe), au vers (enjambements, échelonnement) et à la spatialisation. Le dernier chapitre de la seconde partie est donc consacré à la visibilité de l’écriture sur la page. Cette dernière, corps de l’écriture, révèle dans le poème le corps de l’écrivant. C’est sur le sujet et ses différents visages et représentations que se centre notre dernière partie. Le rythme apparaît, enfin, comme une mosaïque d’espaces du discours et d’espaces de sens (et d’images) qui implique tout autant le locuteur que le lecteur Through the combined analysis of six poem books of contemporary Spanish poetry, this thesis aims to define poetic writings and its rhythm. Rhythm is considered in relation with the notion of space. Starting with the traditional association of rhythm and meter, the first part studies how the metrical space of the writing of verses, with its structures and boundaries, involves the law and its transgression. On the other hand, the second part considers space as a “substance”: poetic writing is analyzed through its development in the language and sentences. Centered on the figure of the “line”, the second conception of rhythm also implies temporality, which is included in the words themselves (the verbs) and generated by the combination of the sentences. However, in the poem books, sometimes linearity is deconstructed by different phenomenon that deal with language (the dissolution of syntaxes), verse (the enjambment, the dissemination on various lines), and the page. The last chapter is dedicated to the visibility of writing on the page. As a concretization of the writing act, the page is also a revelation of the writer of the poem. Our third and last part is centered on the subject, its different faces and representations. Rhythm appears, at last, as a mosaic of discursive and semantic spaces that imply the speaker as much as the reader

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43

Abdelaziz, Salih. "Développement d'un système robotique pour la radiologie interventionnelle sous IRM." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00801844.

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La réalisation de gestes percutanés dans l'IRM ouvre la voie à des pratiques médicales prometteuses. En revanche, l'utilisation de l'IRM reste à ce jour limitée, et ce malgré l'intérêt en terme de qualité d'image. Cela est dû principalement à l'étroitesse du tunnel et à la complexité des gestes réalisés. Pour rendre accessibles de telles pratiques, une assistance robotique semble très pertinente. Pour le concepteur, la réalisation d'un système robotisé compatible IRM n'est pas une tâche facile, étant donné l'espace disponible et la présence d'un champ magnétique intense. C'est dans ce contexte que nous avons développé un assistant robotique, MRGuide, dédié aux traitements du cancer de la prostate dans l'IRM. Il s'agit d'un manipulateur à câbles avec un actionnement déporté. Dans ce travail, de nombreuses contributions menant à la réalisation de ce prototypes ont présentées. Parmi celles‐ci, une instrumentation originale pour estimer la tension des câbles est proposée. Cette instrumentation est basée sur l'utilisation d'une structure en treillis, de mécanismes compliants et de capteurs de déplacement à technologie optique pour assurer la compatibilité avec le scanner. Pour optimiser la géométrie du robot et faciliter son intégration dans l'IRM, une démarche de conception des robots à câbles instrumentés est développée. Cette démarche est basée sur une approche par intervalles. D'autres contributions relatives à la caractérisation de l'espace de travail des robots à câbles instrumentés, à l'étalonnage des capteurs de tension et au développement d'une stratégie de commande adaptée au dispositif sont décrites.

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Chauvin, Julie. "Etude des mécanismes anti-cancéreux induits par milieux activés par jet de plasma froid : vers une nouvelle approche thérapeutique." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30263/document.

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Les thérapies anticancéreuses basées sur des principes physiques (radiofréquences, ultrasons, laser, électroporation...) ont considérablement augmenté lors de la dernière décennie. Leurs objectifs sont de détruire directement les cellules cancéreuses, de favoriser l'entrée ciblée de molécules thérapeutiques ou encore de stimuler le système immunitaire du patient afin d'éliminer la tumeur. Le plasma froid suscite l'intérêt dans le domaine de l'oncologie grâce à sa capacité à générer des espèces réactives oxygénées (ROS) et azotées (RNS) qui peuvent être génotoxiques et cytotoxiques pour les cellules cancéreuses. Deux approches d'utilisation du plasma sont étudiées : soit l'exposition directe de cellules au jet plasma, soit l'exposition indirecte via l'utilisation d'un Milieu Activé par Plasma (PAM). Le PAM étant plus facile à délivrer par injection dans la tumeur, c'est cette approche qui est choisie lors de ces travaux. Le travail de thèse présenté consiste à étudier l'effet génotoxique et cytotoxique du PAM, obtenu après exposition du milieu au jet de plasma d'hélium, sur des tumeurs in vitro et in vivo. Pour les études in vitro, nous avons choisi d'utiliser un modèle 3D : le sphéroïde (MCTS - MultiCellular Tumor Spheroid). Ce modèle présente des caractéristiques proches du modèle in vivo grâce à son organisation en sphéroïde. Les MCTS présentent en effet des gradients de pénétration d'oxygène, de nutriments et de prolifération cellulaire. La première partie de la thèse concerne l'identification et la quantification des espèces générées dans le PAM. Les méthodes d'analyses utilisées sont la résonance paramagnétique électronique, la fluorimétrie, la colorimétrie, la chromatographie en phase liquide et la spectrométrie de masse. Ces analyses ont mis en évidence que la toxicité du PAM était due à plusieurs facteurs : d'un côté la génération de ROS et RNS mais aussi à la dégradation des nutriments pour les cellules contenues dans le milieu via par exemple l'oxydation et la nitrosylation des acides aminés. La deuxième partie est dédiée à l'étude des effets du PAM sur les MCTS HCT-116 (cancer du côlon).[...] Cancer therapies based on physical principles (radiofrequency, ultrasound, laser, electroporation...) have considerably increased in the last decade. Their objectives are to directly destroy cancer cells, to favor the targeted entry of therapeutic molecules or to stimulate the patient's immune system in order to eliminate the tumor. Cold plasma still arouses interest in the field of oncology through its ability to generate reactive oxygen species (ROS) and nitrogen species (RNS) which can be genotoxic and cytotoxic for cancer cells. Two approaches to the use of plasma are studied: either direct exposure of cells to the plasma jet, or indirect exposure via the use of a Plasma Activated Medium (PAM). The PAM being easier to deliver by injection into the tumor, this approach was chosen in this work. The work presented consists in studying the genotoxic and cytotoxic effects of PAM resulting from exposure of the medium to the helium plasma jet on in vitro and in vivo tumors. For in vitro studies, we chose to use a 3D model: the spheroid (MCTS - MultiCellular Tumor Spheroid). This model has similar characteristics to the in vivo model thanks to its spheroidal organization. The spheroids have indeed gradients of oxygen penetration, nutrients and cell proliferation. The first part of the thesis concerns the identification and quantification of the species generated in PAM. The analytical methods used are paramagnetic electronic resonance, fluorimetry, colorimetry, liquid chromatography and mass spectrometry. These analyses revealed that the toxicity of PAM was due to several factors: on the one hand to the generation of ROS and RNS and on the other hand to the degradation of cell nutrients contained in the medium via, for example, the oxidation and nitrosylation of the amino acids. The second part is dedicated to the study of the effects of PAM on HCT-116 (colon cancer) spheroids[...]

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Minig, Vanessa. "Etude du mécanisme de régulation du gène et de l'importance biologique de la superoxyde dismutase à manganèse dans la croissance tumorale mammaire." Thesis, Nancy 1, 2009. http://www.theses.fr/2009NAN10032/document.

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La superoxyde dismutase à Manganèse (SOD Mn ou SOD2) est une enzyme importante dans la défense antioxydante, qui semble jouer un rôle mal défini dans le développement des tumeurs selon l’expression constitutive de son gène. Cependant, les mécanismes de régulation de cette expression constitutive sont mal connus, en particulier dans les cellules tumorales mammaires. Ce travail a reposé sur la mise en évidence préalable d’une protéine, appelée la Damaged DNA Binding 2 (DDB2) protein, se fixant spécifiquement sur la région promotrice du gène SOD2. La DDB2 est connue pour sa participation dans la réparation de l’ADN par excision de nucléotides. Dans un 1er temps, nous avons caractérisé la séquence d’ADN spécifiquement reconnue dans la région proximale du promoteur du gène SOD2, sur laquelle la DDB2 s’y fixe sous la forme d’un monomère, pour réguler négativement la transcription constitutive de la SOD Mn dans les cellules tumorales mammaires non métastatiques de type MCF-7. Par ailleurs, la DDB2 n’est pas impliquée dans le mécanisme d’induction du gène SOD2, lorsque les cellules MCF-7 sont exposées à des substances inductrices. En revanche, nous avons montré que l’absence de la protéine DDB2, associée à celle du facteur de transcription AP-2?, déjà connu comme répresseur du gène SOD2, entraîne une expression constitutive élevée de la SOD Mn dans les cellules tumorales mammaires métastatiques n’exprimant pas le récepteur aux œstrogènes (ER-). De plus, cette expression constitutive élevée est principalement dépendante du facteur de transcription Sp1. Dans un 2ème temps, nous avons évalué la signification biologique de la régulation de l’expression constitutive de la SOD Mn par la DDB2 dans les cellules tumorales mammaires. Nos résultats montrent que la DDB2 active la prolifération des cellules tumorales mammaires ER+, en exerçant sa régulation négative sur l’expression de la SOD Mn. Dans un 3ème temps, nous avons cherché à montrer les conséquences sur la croissance des cellules tumorales mammaires ER-, qui surexpriment naturellement la SOD Mn. Nos résultats révèlent que l’enzyme antioxydante joue un rôle important dans les mécanismes moléculaires impliqués dans le pouvoir invasif des cellules tumorales mammaires ER-. La surexpression de la SOD Mn, associée à un taux faible des enzymes éliminant l’H2O2, entraînent une augmentation du pouvoir invasif déjà élevé des cellules tumorales mammaires ER-, associée une augmentation de l’activité de la métalloprotéinase 9. L’élimination, en présence d’antioxydants, de l’H2O2 libéré par l’activité de la SOD Mn surexprimée, entraîne une inhibition à la fois de la croissance et des capacités invasives des cellules tumorales mammaires ER-. L’ensemble de ce travail contribue à mieux comprendre l’importance de la SOD Mn et du mécanisme de régulation de son gène dans la croissance et l’invasion tumorales. Ainsi ce travail révèle également la SOD Mn et la DDB2 comme de potentiels facteurs prédictifs de la progression tumorale mammaire. Enfin, la découverte de la nouvelle activité biologique de la DDB2 ouvre un vaste champ de perspectives intéressantes en cancérologie mammaire Manganese superoxide dismutase (Mn SOD or SOD2) is an important enzyme in the antioxidizing defence, which seems to play an unclear role in the cancer development, according to the constitutive expression of its gene. However, the regulation of this constitutive expression is not totally known, particularly in the breast cancer cells. This work is based on a preliminary revealing that a protein, called Damaged DNA Binding 2 (DDB2), specifically binds the SOD2 gene promoter. The DDB2 is known for its involvement in the nucleotide excision repair. At first step, we characterized the specific DNA sequence recognized in the proximal area of the SOD2 gene promoter, on which a DDB2 monomer binds, in order to regulate negatively the Mn SOD transcription in the MCF-7 non metastatic breast cancer cells. Besides, DDB2 is not involved in the mechanism of SOD2 gene induction, when MCF-7 cells are exposed to induced substances. However, we showed that the lack of the DDB2 protein, associated with the lack of the AP-2a transcription factor, already known as a repressor of the SOD2 gene, lead to a high Mn SOD constitutive expression in the metastatic breast cancer cells. Furthermore, this high constitutive expression is mainly dependent of the Sp1 transcription factor. Secondly, we estimated the biological meaning of the regulation of the Mn SOD constitutive expression by the DDB2 in the breast cancer cells. Our results show that the DDB2 activates the positive ER breast cancer cell proliferation, by exercising its negative regulation on the Mn SOD expression. Thirdly, we tried to show the consequences on the negative ER breast cancer cell growth, which naturally and highly express the Mn SOD. Our results reveal that the antioxidizing enzyme plays an important role in the molecular mechanisms involved in the invasive capacities of the negative ER breast cancer cells. The high Mn SOD expression, associated in a decrease of the H2O2 detoxifying enzymes expression, enhance the negative ER breast cancer cell invasion and an increase of the matrix metallopeptidase-9 activity. The H2O2 elimination, with specific antioxidants, decreases both negative ER breast cancer cell growth and invasive capacities. This whole work contributes to better understand the Mn SOD importance and the mechanism of its gene regulation, in the tumoral growth and invasion. This work also reveals the Mn SOD and DDB2 as potential predictive factors of the breast cancer progress. Finally, the discovery of this new DDB2 biological activity opens a huge field of interesting perspectives in breast cancer research

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Charbonnel, Marie. "Materialibus ad immaterialia : Peinture murale et piété dans les anciens diocèses de Clermont, du Puy et de Saint-Flour du XIIe au XVe siècle." Thesis, Clermont-Ferrand 2, 2012. http://www.theses.fr/2012CLF20005.

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La peinture murale est envisagée en tant que support matériel de communication profondément attaché au lieu cultuel et dévotionnel qu’est l’église. Par son inscription dans ce lieu et par son caractère monumental, elle constitue un mode de diffusion privilégié pour des messages dont les destinataires appartiennent à la fois aux sphères divine et terrestre. Le lieu et l’espace dans lesquels ces peintures s’inscrivent, doivent alors être envisagés également en termes de fonction et de fréquentation. Cette thèse propose d’envisager les pratiques pieuses et dévotionnelles médiévales (XIIe-XVe siècles), à travers le prisme de la peinture murale dans les anciens diocèses de Clermont, du Puy et de Saint-Flour (1317). Dans un premier temps, sont présentés les cadres d’émergence, à la fois politiques et religieux, des peintures étudiées, une historiographie des études portant sur ce support, les sources envisagées, ainsi que les problématiques présidant à cette étude. Dans un deuxième temps, sont développés les questionnements en lien avec la peinture apposée dans l’espace communautaire, tant dans le sens de la communauté des fidèles que de celle des clercs. Dans un troisième temps, sont abordées les questions inhérentes aux peintures insérées dans l’environnement matériel de la fondation pieuse, servant de cadre à des prières, liturgiques ou non, et s’inscrivant dans le cadre de commandes individuelles et/ou familiales. Le but de cette démarche est de confronter les expressions iconographiques et épigraphiques dans le cadre privé et dans le cadre communautaire. Les enjeux ne sont pas les mêmes, notamment au niveau des signes identifiants et des thèmes iconographiques développés comme le portrait Wall-painting is viewed as a material medium of communication deeply linked to the places of worship and devotion that are churches. As a part of this place et by its monumental character, it forms a privileged way of spread for messages which addressees belong to terrestrial and celestial spheres. Those religious places and spaces, which wall painting is a good part, should consequently be viewed by taking account of its function and attendance. This dissertation proposes to envisage medieval religious practices through the prism of wall painting of the former dioceses of Clermont, Le Puy and Saint-Flour (1317). At first, the political and religious frameworks, historiography of the studies on wall painting and the problematic are exposed. Secondly, questionings induced by murals linked to spaces used by believers and clerical communities are developed. Thirdly, questionings inherent to murals inserted in material environment of the pious foundation, which serve as setting for liturgical or non liturgical prayers, and which are included in an individual and/or family context, are treated. The aim of this study is to consider iconographic and epigraphic expressions within private and community frameworks. Indeed, issues are very different, notably at levels as signs of identity and iconographic themes as portrait

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Rochwert-Zuili, Patricia. ""Du poème à l'histoire. La geste cidienne dans l'historiographie alphonsine et néo-alphonsine (XIIIe-XIVe siècles)"." Phd thesis, Université Paris-Nord - Paris XIII, 1998. http://tel.archives-ouvertes.fr/tel-00130804.

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Décrivant l'ascension sociale d'un groupe de chevaliers valant par leur seule compétence, le "Poème du Cid" proclame le modèle d'une seigneurie personnelle destinée à corriger les effets néfastes d'un régime fondé essentiellement sur la 'nature'. Vouée à servir, quant à elle, les aspirations centralisatrices de la couronne, l'historiographie alphonsine tente d'imposer le modèle d'un ordre royal. Deux discours, donc, différents tant dans leur forme que dans les valeurs qu'ils véhiculent. Et pourtant, le "Poème du Cid" constitue l'essentiel du matériau narratif de l'"Histoire d'Espagne" pour l'histoire de Rodrigue Diaz et d'Alphonse VI. Quels furent, dans ces conditions, les procédés de transfert du discours épique au discours historiographique? Une étude minutieuse des similitudes que présentent les différentes versions de l'"Histoire d'Espagne" ("Chronique de vingt rois", "Version sancienne", "Chronique de Castille") permet de dégager les deux critères de sélection de l'information narrative: sa vraisemblance et sa fonctionnalité. Quatre opérations traduisent les mécanismes d'intégration de la geste à l'histoire: la segmentation, l'uniformisation, l'abréviation et surtout l'amplification. Sur ces remaniements repose l'essentiel du propos monarchique: réaliser la centralisation juridique et valoriser l'acte exemplaire de dépendance du sujet face au seigneur naturel. L'analyse des écarts entre les textes nous informe, à un autre niveau, de l'évolution du discours historiographique lui-même. Si le propos de l'historiographie reste inchangé, en revanche, la voix des destinateurs du récit s'exprime de façon plus personnelle. Ainsi, le texte accorde une large place à la noblesse chevaleresque, ces hommes désireux de gravir la hiérarchie des états en entrant au service du roi et qui, dans le dernier tiers du XIVe siècle, formeront les grandes Maisons Trastamare.

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Vauzour, David. "Étude des propriétés biologiques des constituants des vins de Champagne." Phd thesis, Université Montpellier I, 2004. http://tel.archives-ouvertes.fr/tel-00460764.

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Il a été observé dans le cadre d'enquêtes épidémiologiques tentant d'expliquer le « French Paradox » qu'une consommation modérée et journalière de vin permet d'abaisser quantitativement les risques d'apparition d'accidents cardiovasculaires et/ou de cancer. La communauté scientifique s'est particulièrement intéressée aux vins rouges ou blancs, mais les études portant sur le vin de Champagne sont rares. Partant du Champagne en bouteille, il s'est donc agi dans un premier temps de préparer trois "blocs" représentant la totalité des constituants du Champagne en distinguant les Blancs de blanc des Blancs de noirs. Ils ont été séparés par Chromatographie de Partage Centrifuge, « bioguidée » en fonction des réponses des fractions à des tests d'activité biologique. Ainsi, en plus de celles connues jusque là, six nouvelles molécules ont pu être caractérisées par Résonance Magnétique Nucléaire et/ou spectrométries de masse et ultraviolette. Leurs propriétés biologiques ont alors été étudiées plus en détails, et en particulier dans les domaines de l'hémato-oncologie et de la neurobiologie. Des activités cytotoxiques et antiprolifératives sur des lignées cellulaires cancéreuses, un rôle protecteur sur des mitochondries isolées de cerveau de rat mises en anoxie et une inhibition de l'acétylcholinestérase, enzyme impliquée dans la maladie d'Alzheimer, ont clairement été identifiées in vitro pour les fractions issues des vins de Champagne. Leur pénétration au sein du cytoplasme de neurones, visualisée par des expériences de microscopie confocale de fluorescence, permet de faire l'hypothèse d'une action in vivo. L'analyse par cytométrie de flux des mécanismes biologiques impliqués dans les processus cytotoxiques et antiprolifératifs révèlent un phénomène apoptotique et une dérégulation du cycle cellulaire des lignées cancéreuses employées. De plus l'utilisation de puces à ADN nous a permis d'émettre des hypothèses quand aux voies de signalisation empruntées. En dehors de ces propriétés qui passent par des mécanismes moléculaires spécifiques, les constituants actifs du vin de champagne, assez largement représentés par des molécules polyphénoliques, ont fait l'objet de mesures de leurs propriétés rédox. L'étude menée in vivo sur la capacité antioxydante plasmatique de sujets sains après ingestion de deux coupes de Champagne démontre une contribution des substances naturelles des vins de Champagne dans la protection contre les espèces oxygénées réactives délétères pour l'organisme. Cette capacité antioxydante plasmatique est corrélée à une nette diminution du nombre de substances oxydantes plasmatiques, trente minutes après l'ingestion.

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He, Tiantian. "Studying the Role of Peroxiredoxin 1 in ROS Modulation and Drug Resistance." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112139.

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Les peroxyrédoxines sont des enzymes essentielles de la cellule. Outre leur rôle d’antioxydant, elles sont aussi des régulateurs de la signalisation cellulaire et des suppresseurs de tumeurs. La péroxiredoxine 1 (Prx1) est la plus abondante parmi les six isoformes de peroxyrédoxines humaines. Elle est fréquemment surexprimée dans plusieurs types de cellules cancéreuses, et on a pu associer Prx1 aux processus de carcinogenèse et de métastase, ainsi qu’à la résistance à la radiothérapie ou la chimiothérapie. Ainsi, Prx1 pourrait donc être une cible anticancéreuse intéressante. Au cours de ce travail de thèse, nous avons d’abord évalué l'impact d’une diminution de Prx1 (Prx1 knockdown (Prx1–)) sur la sensibilité cellulaire à des dizaines de médicaments anticancéreux dont la vinblastine, le taxol, la doxorubicine, la daunorubicine, l’actinomycine D, et le 5-fluorouracile, et d’agents connus pour provoquer la production d’espèces réactives de l’oxygène (ROS), dont le peroxyde d'hydrogène, le 2-phényléthyle isothiocyanate, le β-lapachone (β-lap) et la ménadione. Nous avons mis en évidence qu’une diminution de Prx1 augmente significativement la sensibilité des cellules à l'effet cytotoxique de la β-lap et de la ménadione, deux naphtoquinones possédant une activité anti-tumorale.Nous avons étudié les mécanismes responsables de l'augmentation de la cytotoxicité de la β-lap dans un contexte Prx1–. Nous montrons que la toxicité accrue de la β-lap dans des cellules Prx1– est due à une accumulation intracellulaire de ROS. Cet effet est dépendant de l’activité NADPH quinone oxydoréductase (NQO1) et s’accompagne d’une phosphorylation de c-Jun N-terminal kinases (JNK), protein 38 (p38), extracellular signal-regulated kinases (Erk) et des mitogen-activated protein kinases (MAPK), mais aussi d’une diminution des niveaux protéiques de la thiorédoxine 1. En se basant sur le fait que Prx1 est une enzyme antioxydante et un partenaire d'au moins ASK1 et JNK, deux éléments clés de la voie MAPK, nous proposons que la sensibilisation à la β-lap, observée après diminution de Prx1, est provoquée par une action synergique entre l'accumulation de ROS et l'induction de la voie MAPK, conduisant ainsi à l'apoptose.Nous avons ensuite étudié les mécanismes responsables de l'augmentation de la cytotoxicité de la ménadione dans le contexte Prx1–. La sensibilité accrue des cellules à l'effet cytotoxique de la ménadione et également associée à l'accumulation rapide et massive des ROS intracellulaire et à une mort cellulaire ressemblant à la nécrose programmée (necroptosis). L’accumulation de ROS induite par la ménadione et très rapidement détectée dans le cytosol, le noyau, et de façon encore plus importante, dans la matrice mitochondriale. Ce phénomène est en corrélation avec l'oxydation importante des thiorédoxine 2 et peroxiredoxine 3, deux protéines antioxydantes localisées dans la mitochondrie. La diminution de l’expression de Prx1 s’accompagne d’une augmentation des quantités tant de l’ARNm que de la protéine NRH: quinone oxydoréductase 2 (NQO2). Cette augmentation de l'activité de NQO2 est en grande partie responsable de l'accumulation intracellulaire de ROS et de la mort cellulaire après le traitement à la ménadione. Nos données révèlent que l’accumulation de ROS dans les cellules Prx1– provient de la résultante entre l’augmentation de leur production par NQO2 au cours du métabolisme de la ménadione et la diminution de leur élimination par Prx1. Enfin et de façon surprenante, selon la nature des naptoquinones (β-lap ou ménadione), les voies métaboliques qui conduisent à l'accumulation des ROS, ou les voies de signalisation et les mécanismes de mort cellulaire impliqués semblent être distincts Peroxiredoxins have multiple cellular functions as major antioxidants, signaling regulators, molecular chaperones and tumor suppressors. Peroxiredoxin 1 (Prx1) is the most abundant among the six isoforms of human peroxiredoxins. It is frequently over-expressed in various cancer cells, which is known associated with carcinogenesis, metastasis and resistance to radiotherapy or chemotherapy. Prx1 could thus be an interesting anticancer target. In this study, we first evaluated the impact of Prx1 knockdown (Prx1–) on cellular sensitivity to dozens of anticancer drugs including vinblastine, taxol, doxorubicin, daunorubicin, actinomycin D, and 5-fluorouracil, and of reactive oxygen species (ROS)-generating agents, including hydrogen peroxide, 2-phenylethyl isothiocyanate, β-lapachone (β-lap) and menadione. We observed that Prx1 knockdown significantly enhanced cancer cell sensitivity to β-lap and menadione, two naphthoquinones with anti-cancer activity.We first investigated the underlying mechanisms responsible for the specifically enhanced cytotoxicity to β-lap in a Prx1 knockdown context. Prx1 knockdown markedly potentiated β-lap-induced cytotoxicity through ROS accumulation. This effect was largely NAD(P)H:quinone oxidoreductase 1 (NQO1)-dependent and associated with the phosphorylation of c-Jun N-terminal kinases (JNK), protein 38 (p38) and extracellular signal-regulated kinases (Erk) proteins in mitogen-activated protein kinase (MAPK) pathways, and a decrease in thioredoxin 1 protein levels. Based on the fact that Prx1 is a major ROS scavenger and a partner of apoptosis signaling kinase 1 (ASK1) and JNK, two key components of MAPK pathways, we propose that Prx1 knockdown-induced sensitization to β-lap is achieved through the combined action of ROS accumulation and MAPK pathway activation, leading to cell apoptosis.We then investigated the underlying mechanisms responsible for the specifically enhanced cytotoxicity to menadione in Prx1– cells. Enhanced sensitivity to menadione was associated with a rapid and significant intracellular ROS accumulation and necroptotic-like cell death. Menadione-induced ROS accumulation occurred immediately in the cytosol, the nucleus, and even more noticeably in the mitochondrial matrix, correlated with significant oxidation of both mitochondria-localized thioredoxin 2 and peroxiredoxin 3. Prx1 knockdown significantly up-regulated mRNA and protein levels of NRH: quinone oxidoreductase 2 (NQO2). Increased activity of NQO2 was largely responsible for menadione-induced ROS accumulation and consequent cell death. Our data indicate that massive ROS accumulation results from the combined effect of increased ROS generation by higher NQO2 activity during menadione metabolism, and diminished Prx1 scavenging activity. Finally and noteworthy, the metabolic pathways that lead to ROS accumulation, downstream signaling pathways and cell death mechanisms appear to be distinct for β-lap and menadione

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Pierre, Anne-Sophie. "Le métabolisme des acides gras monoinsaturés et la prolifération des cellules cancéreuses coliques : rôle de la Stéaroyl-CoA Désaturase-1 et effets des isomères conjugués de l'acide linoléique." Phd thesis, Université de Bourgogne, 2012. http://tel.archives-ouvertes.fr/tel-01017782.

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Le métabolisme de la cellule cancéreuse s'adapte aux besoins en macromolécules de cette cellule en prolifération et en réponse aux signaux du microenvironnement tumoral. Ainsi, la biosynthèse des acides gras monoinsaturés (AGMI), est augmentée dans les cellules cancéreuses coliques et associée à une augmentation de l'activité de la stéaroyl-CoA désaturase (SCD), enzyme limitante de cette synthèse. Les acides gras polyinsaturés (AGPI) comme les isomères conjugués de l'acide linoléique (CLA), c9,t11 CLA et t10,c12 CLA possèdent à la fois un effet inhibiteur sur l'activité SCD et un effet anti-tumoral dont les mécanismes moléculaires restent à préciser. Dans ce contexte, les objectifs de ce travail furent d'évaluer le rôle de SCD-1 dans la survie de la cellule cancéreuse colique (CCC) et les mécanismes de régulation sous-jacents mais également d'apporter des éléments nouveaux sur les régulations à l'origine de l'effet anti-prolifératif des CLA. Nous avons tout d'abord montré que l'extinction de l'expression de SCD-1 conduit à l'apoptose des CCC dépendante de CHOP. En revanche l'extinction de SCD 1 n'affecte en rien les cellules non cancéreuses. Par ailleurs, nous avons étudié les effets sur la viabilité des CCC de deux isomères de l'acide linoléique le c9,t11-CLA et le t10,c12-CLA in vitro. Nos résultats montrent que seul le t10,c12-CLA induit une mort cellulaire par apoptose des CCC sans affecter la survie de cellules coliques non transformées. Il apparait aussi être le seul isomère à réduire la biosynthèse des AGMI dans les CCC. La mort induite par le t10,c12 CLA dans les CCC est dépendante de l'activation d'un stress du RE via la production d'espèces réactives de l'oxygène.Nos travaux apportent des éléments nouveaux dans la compréhension du rôle de SCD 1 dans la survie des cellules cancéreuses coliques et les mécanismes d'action du t10,c12 CLA. Notre étude soutient l'hypothèse de faire de la biosynthèse des AGMI une cible thérapeutique possible dans le traitement des cancers colorectaux

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Dissertations / Theses on the topic 'Espace de Cantor'

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