Schubert K., Polte T., Bönisch U., Schader S., Holtappels R., Hildebrandt G., Lehmann J., Simon J.C., Anderegg U., Saalbach A. Thy-1 (CD90) regulates the extravasation of leukocytes during inflammation. Eur. J. Immunol. 41, 2011; 645-656 / Saalbach A, Haustein UF, and Anderegg U. A ligand of human Thy-1 is localized on polymorphonuclear leukocytes and monocytes and mediates the binding to activated Thy-1 positive microvascular endothelial cells and fibroblasts. J. Invest. Dermatol. 2000; 115: 882-888 / Wetzel A., Wetzig T., Haustein U.F., Sticherling M., Anderegg U., Simon J.C., Saalbach A. Increased Neutrophil Adherence in Psoriasis: Role of the Human Endothelial Cell Receptor Thy-1 (CD90). Journal of Investigative Dermatology. 2006; 126: 441–452 / Saalbach A., Arnhold J., Leßig J., Simon J. C., Anderegg U. Human Thy-1 induces secretion of matrixmetalloproteinase-9 and CXCL8 from human neutrophils. Eur. J. Immunol. 2008; 38: 1391–1403 / Schmidt M., Gutknecht D., Simon J.C., Schulz J.N., Eckes B., Anderegg U., Saalbach A. Controlling the Balance of Fibroblast Proliferation and Differentiation: Impact of Thy-1. J Invest Dermatol. 2015; 135(7):1893-902 / Saalbach, A., Wetzig, T., Haustein, U.F., and Anderegg, U. Detection of human soluble Thy-1 in serum by ELISA: fibroblasts and activated endothelial cells are a possible source of soluble Thy-1 in serum. Cell Tiss. Res. 1999; 298: 307-315 / Wetzel A, Chavakis T, Preissner K, Sticherling M, Haustein U-F, Anderegg U, Saalbach A. Human Thy-1 (CD90) on Activated Endothel Cells is a Counterreceptor for the Leucocyte Integrin Mac-1 (CD11b/CD18). The Journal of Immunology 2004; 172: 3850-3859

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

SF-1 e LRH-1 são fatores de transcrição que exercem um papel fundamental na produção de esteroides nas gônadas e na suprarrenal, além de estarem envolvidos no processo tumorigênico desses órgãos. Por outro lado, POD-1 apresenta menor expressão em carcinomas adrenocorticais, e parece regular Sf-1. Nesse trabalho foi analisado o papel de POD-1 na regulação de SF-1 e de LRH-1 em células de tumores adrenocorticais. A hiperexpressão de POD-1 resultou em redução da expressão SF-1/SF-1. Em contraste, houve um aumento da expressão gênica de LRH-1, devido à diminuição da expressão de SHP, um regulador negativo de LRH-1. Nas células transfectadas com siRNA-POD-1, os níveis de POD-1 foram reduzidos e de SF-1 aumentado, reforçando o mecanismo regulatório entre os fatores. No ChIP assay, POD-1 se ligou a sequência E-box do promotor de SF-1. Por outro lado, não foi caracterizado a ligação de POD-1 no promotor LRH-1, embora POD-1 tenha se ligado ao E-box do promotor SHP. A redução de SF-1 diminuiu a expressão de StAR, mas não modulou a proliferação das células tumorais. Em resumo, POD-1 pode ter um papel mais amplo como regulador da transcrição de fatores que controlam o processo tumorigênico, e é um candidato a gene supressor de tumor nas células adrenocorticais. / SF-1 and LRH-1 have played a critical role in steroid production, adrenal and gonads. Moreover, there are evidences that they have acted in tumorigenesis process in these organs. POD-1 is downregulated in adrenocortical carcinoma (ACC) it seems to regulate Sf-1. In this work, it has been to analyse the role of POD-1 in SF-1 and LRH-1 regulation in adrenocortical tumor cells. The POD-1 overexpression has reduced SF-1/SF-1 expression. However, there was an increase of LRH-1 gene expression due to SHP expression decrease which is negative regulate of LRH-1. The POD-1 and SF-1 gene expression in transfected cells with siRNA-POD-1 has shown POD-1 decrease and SF-1 increase emphasizing a regulatory mechanism between POD-1 and SF-1. By ChIP assay it was shown that POD-1 binded in SF-1 promoter E-box sequence. It was not characterized that POD-1 binded in LRH-1 promoter, although POD-1 can bind in SHP promoter E-box sequence. The reduction of SF-1 expression by POD-1 has decreased the StAR expression, however, it was not enough to change tumor cell proliferation. In summary, POD-1 must have a wider role as regulator of fator transcription which controls tumorigenese process being a possible candidate as tumor supressor gene in adrenocortical cells.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

[pt] Os modelos autorregressivos são comumente encontrados dentro do contexto de séries hidrológicas, especificamente em séries de vazões e/ou ENA (Energia Natural Afluente). Muitos destes modelos são de ordem 1, possuem parâmetros constantes ou periódicos e necessitam do requisito de normalidade. Segundo a literatura, séries de vazões anuais podem ser aproximadas para distribuições normais, porém em períodos de tempo curtos como diário, semanal e mensal esta característica não é observada, especialmente pelo problema de assimetria. Devido a isto, uma nova classe de modelo de ordem 1 foi estudada na tentativa de suprir tal problema. O novo modelo mantém estrutura autorregressiva, pode ser aditivo, multiplicativo ou híbrido, onde incorpora propriedades aditivas e multiplicativas conjunta- mente, porém suas marginais assumirão distribuição gama. Além disso, a modelagem parte do pressuposto que os Métodos de Momentos são eficientes para estimação de seus parâmetros. Recentemente esta abordagem, sob a forma híbrida, não demonstrou sucesso para o contexto do despacho hidrotérmico brasileiro. O presente trabalho foca na análise completa do modelo híbrido para as séries do Setor Elétrico Brasileiro, trazendo como novidade a estimação via máxima verossimilhança além dos estudos isolados de modelos aditivos e multiplicativos. Os resultados revelaram uma linha de pesquisa promissora, abrindo um campo de possibilidades para que novas ordens superiores a primeira ou distribuições assimétricas possam ser estudadas partindo deste princípio. / [en] Autoregressive models are commonly found in the context of hydrological series, specifically in streamflow and/or ANE series (Affluent Natural Energy). Most of them are models of order 1, which have constant or periodic parameters and need the requirement of normality. According to the literature, annual streamflow series can be approximated for normal distributions, however, in short periods of time, like daily, weekly and monthly, this feature is not observed, especially because of the asymmetry issue. Due to this reason, a new class of model of order 1 was studied for attempting to solve such problem. The new model keeps autoregressive structure and can be additive, multiplicative or hybrid, in which embodies additive and multiplicative properties together, but its marginals will assume gamma distribution. Moreover, this modeling departs from the presupposition that Methods of Moments are efficient to the estimation of its parameters. Recently, this approach, under the hybrid way, has not proved to be successful to the context of Brazilian hydrothermal dispatch. This work focuses on the complete analysis of hybrid model to the series of the Brazilian Electric Sector, bringing, as novelty, Maximum Likelihood Estimation, besides isolated studies of additive and multiplicative models. The results revealed a prosperous line of research, opening a field of possibilities for new orders or asymmetric distributions to be studied starting from this point.

Introduction: Available data suggest an association between presence of secondary (AA) amyloidosis and MCP-1 (monocyte chemoatracttant protein-1) and MIP-1alpha (macrophage inflammatory protein-1 alpha) genes polymorphisms. Some studies have also shown an impact of polymorphisms in exon 3 of SAA 1 (serum amyloid A 1) gene on the incidence of AA amyloidosis in different populations. Methods: The incidence of single genotypes MCP-1, MIP-1alpha and SAA 1 genes was investigated. Serum levels of SAA, MCP-1 and MIP-1alpha were measured and potential relation between serum levels and genotypes were analyzed. All examinations were performed in patients with AA amyloidosis (43), rheumatoid arthritis (RA) without amyloidosis and healthy control group (100). Results: Significantly more frequent occurrence of 1.1/1.1 genotype in SAA 1 was recorded in AA amyloidosis group compared to RA group as well as in control group (p<0,001). No statistically significant differences in distribution of another genotypes were found. Distribution of neither 1.1/1.1 genotype nor another ones did not vary among RA group and control group. No significant difference in distribution of another examined genotypes was recorded among all three groups. Serum concentrations of SAA were statistically significantly higher in AA amyloidosis group...

SF-1 e LRH-1 são fatores de transcrição que exercem um papel fundamental na produção de esteroides nas gônadas e na suprarrenal, além de estarem envolvidos no processo tumorigênico desses órgãos. Por outro lado, POD-1 apresenta menor expressão em carcinomas adrenocorticais, e parece regular Sf-1. Nesse trabalho foi analisado o papel de POD-1 na regulação de SF-1 e de LRH-1 em células de tumores adrenocorticais. A hiperexpressão de POD-1 resultou em redução da expressão SF-1/SF-1. Em contraste, houve um aumento da expressão gênica de LRH-1, devido à diminuição da expressão de SHP, um regulador negativo de LRH-1. Nas células transfectadas com siRNA-POD-1, os níveis de POD-1 foram reduzidos e de SF-1 aumentado, reforçando o mecanismo regulatório entre os fatores. No ChIP assay, POD-1 se ligou a sequência E-box do promotor de SF-1. Por outro lado, não foi caracterizado a ligação de POD-1 no promotor LRH-1, embora POD-1 tenha se ligado ao E-box do promotor SHP. A redução de SF-1 diminuiu a expressão de StAR, mas não modulou a proliferação das células tumorais. Em resumo, POD-1 pode ter um papel mais amplo como regulador da transcrição de fatores que controlam o processo tumorigênico, e é um candidato a gene supressor de tumor nas células adrenocorticais. / SF-1 and LRH-1 have played a critical role in steroid production, adrenal and gonads. Moreover, there are evidences that they have acted in tumorigenesis process in these organs. POD-1 is downregulated in adrenocortical carcinoma (ACC) it seems to regulate Sf-1. In this work, it has been to analyse the role of POD-1 in SF-1 and LRH-1 regulation in adrenocortical tumor cells. The POD-1 overexpression has reduced SF-1/SF-1 expression. However, there was an increase of LRH-1 gene expression due to SHP expression decrease which is negative regulate of LRH-1. The POD-1 and SF-1 gene expression in transfected cells with siRNA-POD-1 has shown POD-1 decrease and SF-1 increase emphasizing a regulatory mechanism between POD-1 and SF-1. By ChIP assay it was shown that POD-1 binded in SF-1 promoter E-box sequence. It was not characterized that POD-1 binded in LRH-1 promoter, although POD-1 can bind in SHP promoter E-box sequence. The reduction of SF-1 expression by POD-1 has decreased the StAR expression, however, it was not enough to change tumor cell proliferation. In summary, POD-1 must have a wider role as regulator of fator transcription which controls tumorigenese process being a possible candidate as tumor supressor gene in adrenocortical cells.

Le VIH-1, ou Virus de l’ImmunoDéficience Humain de type I, est un pathogène intracellulaire dont le cycle de réplication dépend entièrement des machineries cellulaires. Des interactions entre les protéines virales et cellulaires sont donc essentielles pour l’achèvement de chaque étape du cycle de multiplication du VIH-1. Comprendre comment le virus VIH-1 détourne la machinerie cellulaire à son profit est un élément clé pour le combattre. L’objectif de mon travail de thèse était d’explorer le rôle de la protéine Bécline-1 dans la formation et la libération des particules virales. Cette protéine, composant du complexe phosphatydylinositol-3-Phosphate-kinase III (PI3K-III), est impliquée dans l’autophagie, le trafic intracellulaire et la cytocinèse.Au cours de ma thèse, nous avons développé les outils d’ARN interférence afin de décrypter le rôle de Bécline-1 dans le cycle réplicatif du VIH-1. De manière très intéressante, nous avons mis au jour un nouveau rôle de Bécline-1 lors des étapes précoces de la mitose, jamais décrit, ni publié à ce jour. Un mauvais déroulement de la mitose induit de l’instabilité génomique pouvant conduire à la mort cellulaire ou à une transformation maligne. Au cours de cette thèse, nous avons établi que l’extinction de Bécline-1 induit un défaut d’attachement des chromosomes, via leurs kinétochores, aux microtubules, conduisant à un blocage des cellules en prométaphase. Cette extinction provoque un défaut d’organisation du kinétochore en diminuant le recrutement des protéines CENP-E, CENP-F et ZW10 au niveau de cette structure protéique. Nous avons également montré une interaction directe entre Bécline-1 et Zwint-1, une protéine du kinétochore, jouant un rôle essentiel pour l’accrochage des microtubules aux kinétochores. Enfin, nous avons montré que ce nouveau rôle de Bécline-1 dans l’alignement des chromosomes en mitose est indépendant de son association avec ses partenaires du complexe PI3K-III et de son rôle dans l’autophagie.Le second volet de ma thèse a porté sur l’étude du rôle de Bécline-1 au cours du cycle réplicatif du virus. Nos résultats montrent que cette protéine est nécessaire à l’établissement des phases tardives du cycle viral. Nos expériences de production virale montrent que l’extinction de Bécline-1 provoque une forte accumulation des sous-produits de la protéine Gag du virus dans les cellules, et réduit la libération des particules virales dans le milieu extracellulaire. Par immunofluorescence, nous observons que des composants viraux s’accumulent massivement à la membrane sous l’effet de l’extinction de Bécline-1 dans les cellules. Par ailleurs, ces résultats sont dépendants de l’expression du facteur de restriction BST2 dans la cellule. Ces derniers résultats ouvrent d’importantes perspectives quant au rôle de Bécline-1 et du PI3K-III sur le cycle de réplication du VIH-1.L’ensemble de ces travaux démontre l'importance de la protéine Beclin-1, pour le maintien de l'intégrité du génome pendant la mitose et pour le cycle de réplication du VIH 1. / HIV-1, or Human Immunodeficiency Virus type 1, is an intracellular pathogen whose replication cycle entirely depends on cellular machineries. Interactions between the viral and cellular proteins are therefore essential to the completion of each step of HIV-1's multiplication cycle. Understanding how the HIV-1 virus uses the cellular machinery to its own benefit is a key element to combat it. The objective of my thesis work was to explore the role of the Beclin-1 protein in the formation and the release of viral particles. This protein, a component of the phosphatydylinositol-3-Phosphate-kinase III (PI3K-III) complex, is involved in autophagy, intracellular trafficking and cytokinesis. Throughout my thesis researches, we have developed the RNA interference tools in order to decipher the role of Beclin-1 in HIV-1's replicative cycle. Very interestingly, we have found out a new role of Beclin-1 in the early stages of mitosis which had never been described nor published before. A bad execution of mitosis induces genomic instability which can lead to cell death or malignant transformation. During this thesis work, we have demonstrated that the extinction of Beclin-1 causes a defect in the attachment of chromosomes to microtubules through their kinetochores, leading to the locking of cells in prometaphase. This extinction provokes a defect in the organization of the kinetochore by diminishing the recruitment of the CENP-E, CENP-F and ZW10 proteins at the level of this protein structure. We have also found out that there is a direct interaction between Beclin-1 and Zwint-1, a protein of the kinetochore that plays an essential role in the attachment of the kinetochores to the microtubules. Finally, we have demonstrated that this new role of Beclin-1 in the alignment of the chromosomes during mitosis is independent of both its association with its partners from the PI3K-III complex and its role in autophagy. The second strand of my thesis dealt with the role of Beclin-1 in the virus replicative cycle. Our results show that this protein is essential to the setting up of the late phases of the viral cycle. Our experiments of viral production have shown that the extinction of Beclin-1 causes a high accumulation of the by-products of the virus' Gag protein in the cells, and reduces the release of viral particles in the extracellular medium. By immunofluorescence, we detected a massive accumulation of viral components on the membrane as a result of the extinction of Beclin-1 in the cells. Besides, these results depend on the expression of the BST2 restriction factor in the cell. These latter results open up significant prospects regarding the role of Beclin-1 and that of the PI3K-III complex in HIV-1's replication cycle. All these researches demonstrate the importance of the Beclin-1 protein in two mechanisms that allow the maintenance of genomic integrity during mitosis and the HIV-1 replication cycle.

Introduction: Available data suggest an association between presence of secondary (AA) amyloidosis and MCP-1 (monocyte chemoatracttant protein-1) and MIP-1alpha (macrophage inflammatory protein-1 alpha) genes polymorphisms. Some studies have also shown an impact of polymorphisms in exon 3 of SAA 1 (serum amyloid A 1) gene on the incidence of AA amyloidosis in different populations. Methods: The incidence of single genotypes MCP-1, MIP-1alpha and SAA 1 genes was investigated. Serum levels of SAA, MCP-1 and MIP-1alpha were measured and potential relation between serum levels and genotypes were analyzed. All examinations were performed in patients with AA amyloidosis (43), rheumatoid arthritis (RA) without amyloidosis and healthy control group (100). Results: Significantly more frequent occurrence of 1.1/1.1 genotype in SAA 1 was recorded in AA amyloidosis group compared to RA group as well as in control group (p<0,001). No statistically significant differences in distribution of another genotypes were found. Distribution of neither 1.1/1.1 genotype nor another ones did not vary among RA group and control group. No significant difference in distribution of another examined genotypes was recorded among all three groups. Serum concentrations of SAA were statistically significantly higher in AA amyloidosis group...

Ischaemia/Reperfusion Injury (IRI) is the most common cause of acute kidney injury- a devastating clinical problem lacking any specific treatments to promote renal recovery. Macrophages (Mφ) are pleiotropic cells of the innate immune system, with roles spanning host defence, cytotoxicity, clearance of apoptotic cells and promotion of tissue repair. Mφ are also known to be important mediators of renal injury in other experimental models of renal disease including transplantation, obstruction and glomerulonephritis. This work sought to examine the role of Mφ in mediating renal IRI. Conditional renal Mφ and monocyte depletion prior to experimental IRI was achieved by administering diphtheria toxin to the CD11b-DTR transgenic animal. This had no impact on either renal function or structural injury. In contrast liposomal clodronate mediated Mφ depletion provided functional and structural protection from injury. Administration of exogenous apoptotic cells also protected renal function if delivered 24h prior to IRI. Immunodeficient SCID mice exhibited a protected injury phenotype after IRI, however derived no additional protection from the administration of either liposomal clodronate or i.v. apoptotic cells. These findings suggest that the protective phenotype must involve either lymphocyte populations or circulating antibody. Preliminary work demonstrates that SCID mice lack IgM natural antibody which deposits in the kidney in the first 30 minutes after IRI. It was also demonstrated that apoptotic cells bind IgM natural antibody present within the circulation. The potential for the key antioxidant enzyme Heme oxygenase-1 (HO-1) to protect renal function was also examined in aged mice using hemearginate (HA) - a potent HO-1 inducer. Echoing epidemiological studies in humans aged mice had increased susceptibility to IRI, whilst failing to induce medullary HO-1. The main site of medullary HO-1 induction by HA was in medullary Mφ, and the protective phenotype was abolished by Mφ ablation, implicating Mφ as the key mediators of HA induced protection in renal IRI. Final studies employed adenoviral transduction to overexpress HO-1 within bone marrow derived Mφ, leading to a modified phenotype with increased IL- 10 and phagocytosis, and reduced TNFα and NO production. When these were introduced in vivo after IRI renal function was improved, potentially due to accelerated clearance of renal platelet deposition.