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Les tumeurs du cortex surrénalien sont variées et fréquentes dans la population. Bien que des mutations aient été identifiées dans certains syndromes familiaux, les causes génétiques menant à la formation de tumeur du cortex surrénalien ne sont encore que peu connues. Un sous-type de ces tumeurs incluent les hyperplasies macronodulaires et sont pressenties comme la voie d’entrée de la tumorigenèse du cortex surrénalien. L’événement génétique le plus fréquemment observé dans ces tumeurs est l’expression aberrante d’un ou plusieurs récepteurs couplés aux protéines G qui contrôle la production de stéroïdes ainsi que la prolifération cellulaire. L’événement génétique menant à l’expression aberrante de ces récepteurs est encore inconnu. En utilisant le récepteur au peptide insulinotropique dépendant du glucose (GIP) comme modèle, cette étude se propose d’identifier les mécanismes moléculaires impliqués dans l’expression aberrante du récepteur au GIP (GIPR) dans les tumeurs du cortex surrénalien. Une partie clinique de cette étude se penchera sur l’identification de nouveaux cas de tumeurs surrénaliennes exprimant le GIPR de façon aberrante. Les patients étudiés seront soumis à un protocole d’investigation in vivo complet et les tumeurs prélevées seront étudiées extensivement in vitro par RT-PCR en temps réel, culture primaire des tumeurs, immunohistochimie et biopuces. Le lien entre le GIP et la physiologie normal sera également étudiée de cette façon. Une autre partie de l’étude utilisera les nouvelles techniques d’investigation à grande échelle en identifiant le transcriptome de différents cas de tumeurs exprimant le GIPR de façon aberrante. L’importance fonctionnelle des gènes identifiée par ces techniques sera confirmée dans des modèles cellulaires. Cette étude présente pour la première des cas de tumeurs productrices d’aldostérone présentant des réponses aberrantes, auparavant confinées aux tumeurs productrice de cortisol ou d’androgènes surrénaliens. Le cas probant présenté avait une production d’aldostérone sensible au GIP, le GIPR était surexprimé au niveau de l’ARNm et un fort marquage a été identifié dans la tumeur spécifiquement. Dans les surrénales normales, cette étude démontre que le GIP est impliqué dans le contrôle de la production d’aldostérone. Ces résultats ont été confirmés in vitro. Finalement, le profilage à grande échelle des niveaux d’expression de tous les gènes du génome a permis d’isoler une liste de gènes spécifiquement liés à la présence du GIPR dans des hyperplasies du cortex surrénalien. Cette liste inclus la périlipine, une protéine de stockage des lipides dans les adipocytes et la glande surrénale, dont l’expression est fortement réprimée dans les cas GIP-dépendant. Des études dans un modèle cellulaire démontrent que la répression de ce gène par siRNA est suffisante pour induire l’expression du récepteur au GIP et que cette protéine est impliquée dans la stimulation de la stéroïdogénèse par le GIP. En alliant des méthodes d’investigation in vivo de pointe à des techniques in vitro avancée, cette étude offre de nouveaux regards sur les liens entre le GIP et la physiologie de la glande surrénale, que ce soit dans des conditions normales ou pathologiques. / Tumors of the adrenal cortex are varied and frequently found in the population. Aside from rare family cases in which mutations have been identified, the genetic events leading to the formation of adrenocortical tumors remain obscure. A subtype of these tumors includes macronodular hyperplasias, now percieved as the entry point of adrenocortical tumorigenesis. The most commonly observed molecular event in these cases is the presence of aberrantly expressed G-protein coupled receptor that drive steroid production and cellular proliferation. The genetic events leading to these aberrant levels of expression are unknown. This study will use the Glucose-dependent Insulinotropic Polypeptide (GIP) receptor as a model to identify the molecular mecanisms leading to the aberrant expression of the GIP receptor (GIPR) in adrenocortical tumors. The first part of the study will be a clinical investigation of new cases of adrenocortical tumors to screen for aberrant responses to GIP in various types of these tumors. The patients will be evaluated by a thorough clinical investigation protocol and the resected tumors will be extensively analysed in vitro, using real-time RT-PCR, immunohistochemistry, microarray and primary cultures of the tumors. The link between GIP and the normal physiology of the adrenal cortex will also be assessed in normal subjects. The second part of the study will use novel large-scale investigation techniques to determine the transcriptome of different cases of adrenocortical tumors expressing aberrant levels of the GIPR. The functional importance of identified genes will be assessed in cellular models. This study presents the first cases of aldosterone-producing tumors with aberrant responses to hormones, previously confined to cortisol- or androgen producing tumors. The case presented showed an aldosterone production sensitive, among others, to GIP. The GIPR’s mRNA was strongly over expressed and a specific staining was observed in immunohistochemistry. The responses were confirmed in primary cultures of the tumor. In normal adrenals, a role for the control of aldosterone by GIP was also demonstrated. Finally, large-scale profiling of the transcriptome led to the identification of a list of genes with expression levels strictly related to the presence of the GIPR in adrenocortical hyperplasias. One of these genes, perilipin, was strongly repressed specifically in GIP-dependent cases. siRNA techniques were used in a cellular model and confirmed that the repression of perilipin is sufficient to induce the expression of GIPR and that this protein is implicated in the GIP induced steroidogenesis. Allying state-of-the-art in vivo investigation methods to advanced in vitro techniques, the present study identifies novel insights on the link between GIP and the normal adrenal physiology, in normal and pathological conditions.

Les tumeurs du cortex surrénalien sont variées et fréquentes dans la population. Bien que des mutations aient été identifiées dans certains syndromes familiaux, les causes génétiques menant à la formation de tumeur du cortex surrénalien ne sont encore que peu connues. Un sous-type de ces tumeurs incluent les hyperplasies macronodulaires et sont pressenties comme la voie d’entrée de la tumorigenèse du cortex surrénalien. L’événement génétique le plus fréquemment observé dans ces tumeurs est l’expression aberrante d’un ou plusieurs récepteurs couplés aux protéines G qui contrôle la production de stéroïdes ainsi que la prolifération cellulaire. L’événement génétique menant à l’expression aberrante de ces récepteurs est encore inconnu. En utilisant le récepteur au peptide insulinotropique dépendant du glucose (GIP) comme modèle, cette étude se propose d’identifier les mécanismes moléculaires impliqués dans l’expression aberrante du récepteur au GIP (GIPR) dans les tumeurs du cortex surrénalien. Une partie clinique de cette étude se penchera sur l’identification de nouveaux cas de tumeurs surrénaliennes exprimant le GIPR de façon aberrante. Les patients étudiés seront soumis à un protocole d’investigation in vivo complet et les tumeurs prélevées seront étudiées extensivement in vitro par RT-PCR en temps réel, culture primaire des tumeurs, immunohistochimie et biopuces. Le lien entre le GIP et la physiologie normal sera également étudiée de cette façon. Une autre partie de l’étude utilisera les nouvelles techniques d’investigation à grande échelle en identifiant le transcriptome de différents cas de tumeurs exprimant le GIPR de façon aberrante. L’importance fonctionnelle des gènes identifiée par ces techniques sera confirmée dans des modèles cellulaires. Cette étude présente pour la première des cas de tumeurs productrices d’aldostérone présentant des réponses aberrantes, auparavant confinées aux tumeurs productrice de cortisol ou d’androgènes surrénaliens. Le cas probant présenté avait une production d’aldostérone sensible au GIP, le GIPR était surexprimé au niveau de l’ARNm et un fort marquage a été identifié dans la tumeur spécifiquement. Dans les surrénales normales, cette étude démontre que le GIP est impliqué dans le contrôle de la production d’aldostérone. Ces résultats ont été confirmés in vitro. Finalement, le profilage à grande échelle des niveaux d’expression de tous les gènes du génome a permis d’isoler une liste de gènes spécifiquement liés à la présence du GIPR dans des hyperplasies du cortex surrénalien. Cette liste inclus la périlipine, une protéine de stockage des lipides dans les adipocytes et la glande surrénale, dont l’expression est fortement réprimée dans les cas GIP-dépendant. Des études dans un modèle cellulaire démontrent que la répression de ce gène par siRNA est suffisante pour induire l’expression du récepteur au GIP et que cette protéine est impliquée dans la stimulation de la stéroïdogénèse par le GIP. En alliant des méthodes d’investigation in vivo de pointe à des techniques in vitro avancée, cette étude offre de nouveaux regards sur les liens entre le GIP et la physiologie de la glande surrénale, que ce soit dans des conditions normales ou pathologiques. / Tumors of the adrenal cortex are varied and frequently found in the population. Aside from rare family cases in which mutations have been identified, the genetic events leading to the formation of adrenocortical tumors remain obscure. A subtype of these tumors includes macronodular hyperplasias, now percieved as the entry point of adrenocortical tumorigenesis. The most commonly observed molecular event in these cases is the presence of aberrantly expressed G-protein coupled receptor that drive steroid production and cellular proliferation. The genetic events leading to these aberrant levels of expression are unknown. This study will use the Glucose-dependent Insulinotropic Polypeptide (GIP) receptor as a model to identify the molecular mecanisms leading to the aberrant expression of the GIP receptor (GIPR) in adrenocortical tumors. The first part of the study will be a clinical investigation of new cases of adrenocortical tumors to screen for aberrant responses to GIP in various types of these tumors. The patients will be evaluated by a thorough clinical investigation protocol and the resected tumors will be extensively analysed in vitro, using real-time RT-PCR, immunohistochemistry, microarray and primary cultures of the tumors. The link between GIP and the normal physiology of the adrenal cortex will also be assessed in normal subjects. The second part of the study will use novel large-scale investigation techniques to determine the transcriptome of different cases of adrenocortical tumors expressing aberrant levels of the GIPR. The functional importance of identified genes will be assessed in cellular models. This study presents the first cases of aldosterone-producing tumors with aberrant responses to hormones, previously confined to cortisol- or androgen producing tumors. The case presented showed an aldosterone production sensitive, among others, to GIP. The GIPR’s mRNA was strongly over expressed and a specific staining was observed in immunohistochemistry. The responses were confirmed in primary cultures of the tumor. In normal adrenals, a role for the control of aldosterone by GIP was also demonstrated. Finally, large-scale profiling of the transcriptome led to the identification of a list of genes with expression levels strictly related to the presence of the GIPR in adrenocortical hyperplasias. One of these genes, perilipin, was strongly repressed specifically in GIP-dependent cases. siRNA techniques were used in a cellular model and confirmed that the repression of perilipin is sufficient to induce the expression of GIPR and that this protein is implicated in the GIP induced steroidogenesis. Allying state-of-the-art in vivo investigation methods to advanced in vitro techniques, the present study identifies novel insights on the link between GIP and the normal adrenal physiology, in normal and pathological conditions.

[pt] Esta tese é composta de quatro capítulos sobre a relação entre Crédito e Desenvolvimento Econômico. No primeiro capítulo descrevemos os conceitos, relações e mecanismos utilizados nos demais capítulos. No segundo capítulo avaliamos o impacto de reduções em três diferentes restrições financeiras sobre o PIB per capita no Brasil. Para tanto, utilizamos uma versão do modelo de crescimento neoclássico com agentes heterogêneos e três fricções financeiras. O modelo é calibrado para a economia brasileira em 2009 e fazemos exercícios de simulação. No primeiro exercício, uma redução do custo de participação no mercado de crédito, que permitiria que o percentual de firmas com crédito na economia fosse igual à média dos países desenvolvidos, geraria um aumento no PIB per capita de 3,6 por cento. No segundo exercício, uma redução do custo de monitoramento, que permitiria que o spread na economia fosse igual ao spread médio nos países desenvolvidos, geraria uma elevação no PIB per capita de 1,7 por cento. No terceiro exercício avaliamos um relaxamento nas restrições de endividamento. Os resultados mostram que a redução dos colaterais no Brasil para o nível dos países desenvolvidos elevaria o PIB per capita em 12 por cento. No terceiro capítulo buscamos analisar os efeitos macroeconômicos do aprofundamento do crédito com recursos livres no Brasil no período 2001-2011. Em termos mais específicos, avaliamos os impactos do aumento do crédito sobre o PIB per capita. Para tanto, utilizamos uma versão do modelo de crescimento neoclássico com agentes heterogêneos, restrições de crédito e escolha ocupacional, calibrado para a economia brasileira em 2001 e simulamos, no modelo, o aumento do crédito com recursos livres ocorrido no período. No exercício realizado, o aumento no crédito com recursos livres para as firmas de 10 por cento, em 2001, para 15 por cento do PIB em 2011, gerou um aumento de 1,5 por cento no PIB per capita no período. No quarto capítulo, nosso objetivo é avaliar o impacto do aumento do crédito no Brasil no período 2004-2008 sobre o PIB per capita, com a utilização do modelo de Lloyd-Ellis e Bernhardt (2000). Assim podemos comparar os resultados desse modelo com os resultados do modelo utilizado no terceiro capítulo. Na implementação do modelo, utilizamos uma abordagem mista de estimação e calibração para a economia brasileira em 2004. No exercício realizado, o aumento no acesso ao crédito elevou o PIB per capita em 2 por cento entre 2004 e 2008. / [en] This thesis is composed of four chapters on the relationship between Credit and Development Economics. In the first chapter we describe the concepts, relationships and mechanisms used in the other chapters. In the second chapter we evaluated the impact of reductions in three different financial constraints on GDP per capita in Brazil. To do so, we use a version of the neoclassical growth model with heterogeneous agents and three financial frictions. The model is calibrated for the Brazilian economy in 2009 and we do simulation exercises. In the first exercise, a reduction in the cost of participation in the credit market, which would allow the percentage of firms with credit in the economy to be equal to the average of the developed countries, would generate an increase in GDP per capita of 3.6 percent. In the second exercise, a reduction in the cost of monitoring, which would allow the spread in the economy to be equal to the average spread in developed countries, would generate a rise in GDP per capita of 1.7 percent. In the third exercise we evaluated a relaxation in the borrowing constraint. The results show that the reduction of collaterals in Brazil to the level of developed countries would raise GDP per capita by 12 percent. In the third chapter we seek to analyze the macroeconomic effects of the deepening of credit with free resources in Brazil in the period 2001-2011. In more specific terms, we evaluate the impacts of credit growth on GDP per capita. To do so, we used a version of the neoclassical growth model with heterogeneous agents, credit restrictions and occupational choice, calibrated for the Brazilian economy in 2001 and simulated in the model the increase in credit with free resources occurred in the period. In the exercise, the increase in free resources credit for firms from 10 percent in 2001 to 15 percent of GDP in 2011 generated a 1.5 percent increase in GDP per capita in the period. In the fourth chapter, our objective is to evaluate the impact of the increase of credit in Brazil in the period 2004-2008 on GDP per capita, using the model of Lloyd-Ellis and Bernhardt (2000). Thus we can compare the results of this model with the results of the model used in the third chapter. In the implementation of the model, we used a mixed approach of estimation and calibration for the Brazilian economy in 2004. In the exercise carried out, the increase in access to credit raised GDP per capita by 2 percent between 2004 and 2008.

La classification des personnes publiques s’est bâtie sur une distinction dualiste avec d’un côté, la catégorie des collectivités territoriales et de l’autre, celle des établissements publics. A cause des réticences du juge et de la doctrine, la question de l’existence de nouvelles personnes publiques est restée scellée jusqu’à la troisième voie ouverte par le législateur et l’apparition des groupements d’intérêt public (GIP). Les GIP ont été les premières structures qualifiées de personnes publiques innomées. Ensuite, la jurisprudence a consacré l’institution juridique de personnes publiques sui generis à l’image de la Banque de France. Dans les années 2000, le législateur a étendu la liste des personnes publiques innomées en créant une nouvelle forme d’autorité administrative indépendante, les autorités publiques indépendantes dotées de la personnalité morale. Ces personnes publiques ont été créées en vue de moderniser l’action administrative. Elles sont parfois présentées comme des nouvelles formules juridiques venant concurrencer l’établissement public devenu, semble-t-il, une formule désuète au regard des impératifs de la modernisation de la gestion publique. Toutefois, les nouvelles personnes publiques se différencient difficilement de l’établissement public. En effet, ces nouvelles structures sont dotées de la personnalité publique et elles sont soumises au principe de spécialité. Par conséquent, il est possible de rapprocher les nouvelles personnes publiques de la catégorie classique de l’établissement public. En définitive, la grande souplesse et la diversité du statut des établissements publics permettent de dégager l’existence de plusieurs catégories d’établissements publics parmi lesquelles il convient de ranger les nouvelles personnes publiques spéciales. / Classification of public entities is built on a dualistic distinction with one hand, the category of local authorities and the other, that of public establishments. Because of the reluctance of judge and doctrine, the question of the existence of new public entities remained sealed until the third path opened by the legislature and the emergence of public interest groups (GIP). The GIP were the first structures of qualified persons unnamed public. Next, the jurisprudence has dedicated legal institution sui generis public persons in the image of the Bank of France. In the 2000s, the legislature has expanded the list of unnamed public by creating a new form of independent administrative authority, public authorities with independent legal personality. These public entities were created to modernize administrative action. They are sometimes presented as new legal formulas from competing public establishment became, it seems, an outdated formula under the imperatives of modernization of public administration. However, the new public figures hardly differ from the public establishment. Indeed, these new structures have the public persona and are subject to the principle of specialty. Therefore, it is possible to bring new entities public the classical category of public establishment. Ultimately, the flexibility and diversity of the status of public establishments can identify the existence of several categories including public institutions should store the new special public entities.

School inclusion has been a challenge for many teachers who work on regular school classrooms. A number of factors hinder the pedagogical practice of these teachers in their teaching with students who are the target audience of special education. Besides, it is observed that, when dealing with school inclusion of gifted and talented students (G/T), there is resistance from some teachers. This fact lies on the lack of knowledge about the theme of G/T, which may occur due to the wrong conceptions socially widespread, adding to that an incipient initial education in relation to G/T students. Accordingly, it is necessary to create support networks so that school inclusion of G/T students becomes effective. In this sense, the family could be a support network and set up a partnership with the school. Thus, both can articulate and organize a collaborative work on behalf of school inclusion of the G/T child. After reflecting about the situation exposed, this study proposes the following thesis: school inclusion of the G/T child can be effective when family and school act in conjunction in this process, eliminating/diminishing the barriers that hinder this partnership, since the family can influence the school inclusion of the G/T child. This study included 12 families with children identified as G/T more than a year ago, and regularly attended the Giftedness Incentive Program (GIP) during the year of 2014, seven special educators, six teachers from early grades and five counseling teachers that, in the year of 2015, worked with G/T students. Regarding the method, the study case within the qualitative approach was chosen. The instruments of data collection selected were: narrative interview, Questionnaire of Family System Characterization Version – Parents or Guardians (DESSEN, 2011), Checklist of Shared Routine and Engagement between Family-school, Version for Teachers, and Checklist of Shared Routine and Engagement between Family-school, Version for Parents (mother, father, or guardian), both validated by Dessen and Polonia (2011). The interviews were analyzed qualitatively and from the analysis of frequency, through categories already defined by the authors of the instrument. The final considerations point to a relation between family and school that is still incipient, due to the fact that some barriers/constraints were identified, having prevailed an accusative relationship, which may be hindering the construction of a partnership relation. There were specific cases in which there was conjunction between both institutions, and that result in greater influence/participation of the family in the school life of the G/T child. Therefore, the study raises the need to offer continuous education for both the family and the school, aiming at broadening the debate regarding the importance that both have in creating a support network so that, together, they can articulate actions on behalf of school inclusion of the child who is also a G/T student. / A inclusão escolar tem sido um desafio para muitos professores que atuam nas classes regulares de ensino. Diversos fatores dificultam a prática pedagógica desses em sua atuação com os alunos que constituem o público-alvo da educação especial. Além disso, observa-se que, quando se trata da inclusão escolar dos alunos com altas habilidades/superdotação (AH/SD), há resistência por parte de alguns professores. Esse fato reside no desconhecimento da temática das AH/SD, decorrente, possivelmente, das concepções equivocadas difundidas socialmente, somado a uma formação inicial incipiente no que se refere aos alunos com AH/SD. Sendo assim, é necessário formar redes de apoio para que se efetive a inclusão escolar do aluno com AH/SD. Nesse sentido, a família pode ser uma rede de apoio e tornar-se parceira da escola. Assim, ambas podem se articular e organizar um trabalho colaborativo em prol da inclusão escolar do filho/aluno com AH/SD. Após refletir sobre as situações expostas, propõem-se a seguinte tese: a inclusão escolar do filho/aluno com AH/SD será efetivada quando a família e a escola atuarem de forma articulada nesse processo, eliminando as barreiras que dificultam essa parceria, uma vez que a família constitui-se como influente na inclusão escolar do filho com AH/SD. Para verificar a tese, o objetivo geral foi compreender a articulação entre família e escola, verificando as barreiras que dificultam essa parceria, além de visualizar possíveis influências da família no processo de inclusão escolar do filho/aluno com AH/SD. Participaram da pesquisa 12 famílias com filhos identificados com AH/SD há mais de um ano e que foram assíduos durante o ano de 2014 no Programa de Incentivo ao Talento (PIT), sete educadores especiais, seis professores dos anos iniciais e cinco professoras conselheiras que, no ano de 2015, atuaram com os alunos com AH/SD. Em relação ao método, optou-se pela abordagem qualitativa, do tipo estudo de caso. Os instrumentos de coleta de dados selecionados foram: entrevista narrativa, Questionário de Caracterização do Sistema Familiar Versão – Pais ou Responsável (DESSEN, 2011), Checklist da Rotina Compartilhada e Envolvimento entre Família-escola, Versão para Professores e Checklist da Rotina Compartilhada e Envolvimento entre Família-escola Versão Pais (mãe, pai ou responsável), ambos validados por Dessen e Polonia (2011). As entrevistas foram analisadas de forma qualitativa/descritiva articulada com o referencial teórico que subsidiou a tese. Os Checklists foram analisados qualitativamente e a partir da análise de frequência, por meio de categorias já determinadas pelas autoras dos instrumentos. As considerações finais apontam para uma relação entre família e escola ainda incipiente, pois algumas barreiras/entraves foram identificadas, tendo prevalecido uma relação acusativa, o que pode estar dificultando a construção de uma relação de parceria. Foram pontuais os casos em que houve uma articulação entre ambas as instituições e que tenham como resultado maior influência/participação da família na vida escolar do filho com AH/SD. Portanto, sinaliza-se a necessidade de ofertar uma formação continuada tanto para a escola quanto para a família, visando ampliar o debate para a importância de ambas formarem uma rede de apoio para que juntas articulem ações em prol da inclusão escolar do filho que também é aluno com AH/SD.

La fonction de reproduction est sous le contrôle de la neurohormone hypothalamique GnRH qui régule la synthèse et la libération des gonadotropines hypophysaires. La GnRH agit par l’intermédiaire d’un récepteur couplé aux protéines G exprimé à la surface des cellules gonadotropes, le récepteur de la GnRH (RGnRH). Ce récepteur, chez les mammifères, a la particularité d’être dépourvu de queue C terminale ce qui le rend insensible aux systèmes classiques de désensibilisation. Ainsi, les mécanismes qui régulent l’efficacité et la spécificité de sa signalisation demeurent mal connus. Nous avons recherché des partenaires d’interaction du RGnRH, jusqu’alors inconnus, avec l’idée que ces protéines en interagissant avec les domaines intracellulaires du récepteur influenceraient son couplage aux voies de signalisation. Nos travaux ont permis d’identifier le premier partenaire d’interaction du RGnRH : la protéine SET. Par des expériences de « GST pull down », nous avons montré que SET interagit directement avec le RGnRH via le premier domaine intracellulaire du récepteur. Cette interaction implique des séquences riches en acides aminés basiques sur le récepteur et les domaines N- et C-terminaux de SET. Nous avons également montré, par co-immunoprécipitation, que le RGnRH dans sa conformation native interagit avec la protéine SET dans les cellules gonadotropes alphaT3-1 et, par immunocytochimie, que les deux protéines colocalisent à la membrane plasmique. En développant au laboratoire des outils biosenseurs permettant de mesurer avec une grande sensibilité et en temps réel les variations intracellulaires de calcium et d’AMPc, nous avons mis en évidence que le RGnRH se couple non seulement à la voie calcique mais aussi à la voie AMPc dans la lignée alphaT3-1, apportant pour l’AMPc la première démonstration d’un tel couplage. En utilisant différentes stratégies expérimentales visant à diminuer ou au contraire favoriser l’interaction du récepteur avec SET (ARN antisens, peptide correspondant à la première boucle intracellulaire du récepteur, surexpression de SET), nous avons montré que SET induit une réorientation de la signalisation du RGnRH de la voie calcique vers la voie AMPc. Nos résultats concernant l’activité du promoteur du gène du Rgnrh nous conduisent à postuler que SET pourrait favoriser l’induction par la GnRH de gènes régulés via la voie AMPc et notamment celui codant le RGnRH. Nos travaux mettent également en évidence que la GnRH régule non seulement l’expression de la protéine SET dans les cellules gonadotropes mais aussi son degré de phosphorylation favorisant ainsi sa relocalisation dans le cytoplasme des cellules alphaT3-1. Ceci suggère que la GnRH exerce une boucle de régulation permettant d’amplifier l’action de SET sur la signalisation de son propre récepteur. Enfin, nous avons mis en évidence que l’expression de SET est fortement augmentée dans l’hypophyse au moment du prœstrus chez le rat, apportant ainsi la première démonstration d’une variation de SET dans un contexte physiologique. Étant donné que le couplage du RGnRH à la voie de signalisation AMPc est augmenté au moment du prœstrus, nos résultats suggèrent que SET pourrait jouer un rôle important in vivo en favorisant ce couplage à ce stade particulier du cycle œstrien. / Reproductive function is under the control of the hypothalamic neurohormone GnRH, which regulates the synthesis and the release of pituitary gonadotropins. GnRH acts on a G-protein coupled receptor expressed at the surface of pituitary gonadotrope cells, the GnRH receptor (GnRHR). This receptor, in mammals, is unique because it is devoided of the C terminal tail, which makes it insensitive to classical desensitization processes. Therefore, the mechanisms that regulate the efficacy and the specificity of its signaling are still poorly known. We searched for interacting partners of GnRHR with the idea that these proteins by interacting with the intracellular domains of the receptor could influence receptor coupling to its signaling pathways. Our work identified the first interacting partner of GnRHR: the protein SET. By GST pull down assays, we showed that SET interacts directly with GnRHR through the first intracellular loop of the receptor. This interaction involves sequences enriched in basic amino acids in the receptor and both N- and C terminal domains of SET. We also showed, by co-immunoprecipitation, that GnRHR in its native conformation interacts with the endogenous SET protein in gonadotrope alphaT3-1 cells and, by immunocytochemistry that the two proteins colocalize at the plasma membrane. By developing in the laboratory biosensors tools that allow to measure with high sensitivity and in real-time intracellular variations in calcium and cAMP concentrations, we demonstrated that GnRHR couples not only to the calcium pathway but also to the cAMP pathway in alphaT3-1 cell line, providing for cAMP the first demonstration of such coupling. Using several experimental strategies to reduce or increase receptor interaction with SET (small interfering RNA, peptide corresponding to the first intracellular loop of the receptor, overexpression of SET), we have shown that SET induces a switch of GnRHR signaling from calcium to cAMP pathway. Our results concerning the activity of the Gnrhr gene promoter led us to postulate that SET could favor the induction by GnRH of genes regulated through the cAMP pathway, notably those encoding the GnRHR. Our study also showed that GnRH regulates not only SET protein expression in gonadotropes, but also its phosphorylation level leading to its relocation in the cytoplasm of alphaT3-1 cells. This suggests that GnRH induces a regulatory loop to amplify SET action on signaling of its own receptor. Finally, we demonstrated that SET expression is markedly increased in the pituitary gland at prœstrus in female rats, providing the first demonstration of a variation of SET expression in a physiological context. Given that GnRHR coupling to the cAMP pathway is increased at prœstrus, our results suggest that SET may play an important role in vivo by promoting such coupling at this particular stage of the estrus cycle.

Phenacoccus peruvianus (Hemiptera: Pseudococcidae) is an invasive mealybug of Neotropical origin, first reported in the Mediterranean Basin in Almeria (Spain) in 1999. In the following years the mealybug spread into other Mediterranean regions and has also been recorded in Portugal and France, as well as in Sicily, Corsica and the Balearic Islands. Phenacoccus peruvianus is a polyphagous species and damages economically important ornamental plants. Since this was a relatively unknown species, during the first years of invasion, the mealybug was managed by the application of chemical treatments with wide-spectrum pesticides. However, the latest European directive on pesticide use reduces or even forbids pesticide applications in a wide range of urban green areas, giving significant priority to biological control (European Parliament and Council 2009). This thesis sets the basis for introducing biological control into a P. peruvianus management program in urban landscapes, focusing on its characterization, sampling, biology and control. In order to facilitate the identification of this and other mealybug species, we characterised 33 mealybug populations infesting crops and ornamental plants in Eastern Spain, using a combination of molecular and morphological techniques. This characterisation led to the identification of ten mealybug species and made routine identification possible through DNA sequencing or the use of derived species-specific molecular tools. The sequences obtained also add to the phylogenetic knowledge of the Pseudococcidae family and provide insight into the invasion history of some species. Phenacoccus peruvianus populations were high in bougainvillea plants during spring and summer, declining to almost undetectable levels in autumn and winter. The mealybug was mainly found in bracts and there were no significant migrations between plant strata. Phenacoccus peruvianus showed a high aggregated distribution on bracts, leaves and twigs. We recommend a binomial sampling of 200 leaves and an action threshold of 55% infested leaves for IPM purposes in urban landscapes. Its most abundant natural enemies were found to be the primary parasitoids Acerophagus n. sp. near coccois and Leptomastix epona Walker (Hymenoptera: Encyrtidae). We also identified several predator species from the Anthocoridae, Coccinellidae, Chamaemyiidae, and Chrysopidae families. Phenacoccus peruvianus populations were lower during the second and third year of the survey, coinciding with an increase in the parasitoid Acerophagus sp. populations, which displaced the native L. epona. Differential female offspring and resource preemption are discussed as the main reasons for this displacement. To obtain further information on the biology of the new parasitoid Acerophagus sp. we determined some traits of its reproductive and feeding strategies. Acerophagus sp. egg load reached its maximum when it was 5 days old with almost 30 mature eggs. Phenacoccus peruvianus second and third nymphal instars and adults were suitable for parasitism and efficient encapsulation was low (10.76 ± 0.31 %). The parasitoid always preferred older instars when different host instars were available. Acerophagus sp. developed as a solitary parasitoid in the second instar and as a gregarious parasitoid in older instars (2¿4 parasitoids per host). Moreover, it reproduced parthenogenetically and all the emerged offspring were females. Immature development lasted between 20 and 22 days at 25°C and 65% HR. Under these conditions, adults lived for longer than 20 days when fed on honey, but fewer than 3 days when fed on naturally occurring sugar sources (host honeydew and Bougainvillea glabra flowers). / Beltrà Ivars, A. (2014). Biology and management of the invasive mealybug Phenacoccus peruvianus (Hemiptera: Pseudococcidae) in urban landscapes [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/37233 / TESIS

Bypass or resection of the stomach and oesophagus, has long been recognised to result in profound changes in the handling of ingested nutrients. This results in significant morbidity after radical surgery for oesophago-gastric cancer, in particular post-prandial hypoglycaemia, altered appetite, early satiety and noxious post-prandial symptoms. By profiling and challenging the gut hormone axis in healthy volunteers and patients who had undergone total or subtotal gastrectomy, or oesophagectomy, this thesis explores the possible causative mechanisms for the challenges faced by this patient population. In the surgical groups, an oral glucose tolerance test (OGTT) resulted in enhanced secretion of satiety and incretin gut hormones (GLP-1, GIP, PYY) and insulin, followed by hypoglycaemia in a cohort of patients. Continuous glucose monitoring of gastrectomy participants over two weeks of normal lifestyle identified an increased incidence of day and night time hypoglycaemia. RNAseq and mass spectrometry based peptidomics of human and murine enteroendocrine cells in the pre- and post-operative populations revealed no significant change in the underlying cellular pathways for nutrient sensing and gut hormone secretion, indicating that the altered hormone secretion is primarily driven by accelerated nutrient transit, rather than adaptive changes in the gut. Finally, specific blockade of the GLP-1 receptor in post-gastrectomy patients using Exendin 9-39 normalised insulin secretion and prevented reactive hypoglycaemia after an OGTT. In conclusion, profound changes in gut hormone secretion as a result of enhanced nutrient transit after foregut surgery likely underlie the early and late post-prandial symptoms seen in this group, and therapies specifically targeting the gut hormone axis, and GLP-1 in particular, could be the first targeted treatments for post-gastrectomy syndromes.

In this study, methodologies for modeling grey uncertainty in water resources systems are developed, specifically for the problems in two identified areas in water resources: waste load allocation in streams and floodplain planning. A water resources system is associated with some degree of uncertainty, due to randomness of hydrologic and hydraulic parameters, imprecision and subjectivity in management goals, inappropriateness in model selection, inexactness of different input parameters for inadequacy of data, etc. Uncertainty due to randomness of input parameters could be modeled by the probabilistic models, when probability distributions of the parameters may be estimated. Uncertainties due to imprecision in the management problem may be addressed by the fuzzy decision models. In addition, some parameters in any water resources problems need to be addressed as grey parameters, due to inadequate data for an accurate estimation but with known extreme bounds of the parameter values. Such inexactness or grey uncertainty in the model parameters can be addressed by the inexact or grey optimization models, representing the parameters as interval grey numbers. The research study presented in this thesis deals with the development of grey and fuzzy optimization models, and the combination of the two for water resources systems decision-making. Three grey fuzzy optimization models for waste load allocation, namely (i) Grey Fuzzy Waste Load Allocation Model (GFWLAM), (ii) two-phase GFWLAM and (iii) multiobjective GFWLAM, and a Grey Integer Programming (GIP) model for floodplain planning, are developed in this study. The Grey Fuzzy Waste Load Allocation Model (GFWLAM) for water quality management of river system addresses uncertainty in the membership functions for imprecisely stated management goals of the Pollution Control Agency (PCA) and dischargers. To address the imprecision in fixing the boundaries of membership functions (also known as membership parameters), the membership functions themselves are treated as imprecise in the model and the membership parameters are expressed as interval grey numbers. The conflict between the fuzzy goals of PCA and dischargers is modeled using the concept of fuzzy decision, but because of treating the membership parameters as interval grey numbers, in the present study, the notion of ‘fuzzy decision’ is extended to the notion of ‘grey fuzzy decision’. A terminology ‘grey fuzzy decision’ is used to represent the fuzzy decision resulting from the imprecise membership functions. The model provides flexibility for PCA and dischargers to specify their aspirations independently, as the membership parameters for membership functions are interval grey numbers in place of a deterministic real number. In the solution, optimal fractional removal levels of the pollutants are obtained in the form of interval grey numbers. This enhances the flexibility and applicability in decision-making, as the decision-maker gets a range of optimal solutions for fixing the final decision scheme considering technical and economic feasibility of the pollutant treatment levels. The methodology is demonstrated with the case studies of a hypothetical river system and the Tunga-Bhadra river system in Karnataka, India. Formulation of GFWLAM is based on the approach for solving fuzzy multiple objective optimization problem using max-min as the operator, which usually may not result in a unique solution. The two-phase GFWLAM captures all the alternative optimal solutions of the GFWLAM. The solution technique in the Phase 1 of two-phase GFWLAM is the same as that of GFWLAM. The Phase 2 maximizes upper bounds and minimizes lower bounds of decision variables, keeping the optimal value of goal fulfillment level same as obtained in the Phase 1. The two-phase GFWLAM gives the unique, widest, intervals of the optimal fractional removal levels of pollutant corresponding to the optimal value of goal fulfillment level. The solution increases the widths of interval-valued fractional removal levels of pollutants by capturing all the alternative optimal solutions and thus enhances the flexibility and applicability in decision-making. The model is applied to the case study of Tunga-Bhadra river system, which shows the existence of multiple solutions when the GFWLAM is applied to the same case study. The width of the interval of optimal fractional removal level plays an important role in the GFWLAM, as more width in the fractional removals implies a wider choice to the decision-makers and more applicability in decision-making. The multiobjective GFWLAM maximizes the width of the interval-valued fractional removal levels for providing a latitude in decision-making and minimizes the width of goal fulfillment level for reducing the system uncertainty. The multiobjective GFWLAM gives a new methodology to get a satisfactory deterministic equivalent of a grey fuzzy optimization problem, using the concept of acceptability index for a meaningful ranking between two partially or fully overlapping intervals. The resulting multiobjective optimization model is solved by fuzzy multiobjective optimization technique. The consistency of the solution is verified by solving the problem with fuzzy goal programming technique. The multiobjective GFWLAM avoids intermediate submodels unlike GFWLAM, so that the solution from a single deterministic equivalent of the GFWLAM adequately covers all possible situations. Although the solutions obtained from multiobjective GFWLAM provide more flexibility than those of the GFWLAM, its application is limited to grey fuzzy goals expressed by linear imprecise membership functions only, whereas GFWLAM has the capability to solve the model with any monotonic nonlinear imprecise membership functions also. The methodology is demonstrated with the case studies of a hypothetical river system and the Tunga-Bhadra river system in Karnataka, India. The Grey Integer Programming (GIP) model for floodplain planning is based on the floodplain planning model developed by Lund (2002), to identify an optimal mix of flood damage reduction options with probabilistic flood descriptions. The model demonstrates how the uncertainty of various input parameters in a floodplain planning problem can be modeled using interval grey numbers in the optimization model. The GIP model for floodplain planning does not replace a post-optimality analysis (e.g., sensitivity analysis, dual theory, parametric programming, etc.), but it provides additional information for interpretation of the optimal solutions. The results obtained from GIP model confirm that the GIP is a useful technique for interpretation of the solutions particularly when a number of potential feasible measures are available in a large scale floodplain planning problem. Though the present study does not directly compare the GIP technique with sensitivity analysis, the results indicate that the rigor and extent of post-optimality analyses may be reduced with the use of GIP for a large scale floodplain planning problem. Application of the GIP model is demonstrated with the hypothetical example as presented in Lund (2002).