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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Não-adesão ao tratamento em pacientes com doença de Crohn: prevalência e fatores de risco

Cornélio, Rita de Cássia Azevedo Couto 26 June 2008 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-03-24T15:20:36Z No. of bitstreams: 1 ritadecassiaazevedocoutocornelio.pdf: 3370166 bytes, checksum: e79af08a636d474eca822391703dcc7c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-27T17:36:55Z (GMT) No. of bitstreams: 1 ritadecassiaazevedocoutocornelio.pdf: 3370166 bytes, checksum: e79af08a636d474eca822391703dcc7c (MD5) / Made available in DSpace on 2017-03-27T17:36:55Z (GMT). No. of bitstreams: 1 ritadecassiaazevedocoutocornelio.pdf: 3370166 bytes, checksum: e79af08a636d474eca822391703dcc7c (MD5) Previous issue date: 2008-06-26 / CONTEXTO: A não-adesão ao tratamento medicamentoso, em algum grau, ocorre universalmente. É uma das principais causas de insucesso no tratamento das doenças crônicas, tal como a doença de Crohn. OBJETIVO: Em doentes com doença de Crohn, avaliar a prevalência e os fatores de risco associados à baixa adesão ao tratamento medicamentoso. MÉTODOS: No período entre julho de 2006 e julho de 2007 foram incluídos prospectivamente, para avaliação da não-adesão ao tratamento, 100 doentes com doença de Crohn em seguimento clínico no ambulatório de doenças inflamatórias intestinais. Os pacientes responderam ao Teste de Medida de Adesão a Tratamentos de Morisky e Green, modificado. De acordo com este teste, os pacientes foram classificados em dois grupos, conforme o grau de adesão: adesão e não-adesão. A não-adesão foi subdividida em intencional e não-intencional. Variáveis clínicas, psicológicas e farmacoterapêuticas foram pesquisadas na busca de possíveis fatores associados à não-adesão. RESULTADOS: Entre os pacientes avaliados, 64% apresentaram escore compatível com não-adesão. O perfil mais frequente de não-adesão foi o do tipo não-intencional, e os pacientes mostraram ter conhecimento e motivação para o tratamento. Na comparação entre os dois grupos observou-se somente uma tendência a não-adesão entre os pacientes mais jovens (P = 0,07) e de raça não-branca (P = 0,06). Não houve correlação significativa entre o grau de adesão e as variáveis psicológicas e farmacoterapêuticas. CONCLUSÕES: Em pacientes com doença de Crohn, a prevalência de não-adesão ao tratamento medicamentoso é elevada (64%). Indivíduos jovens e aqueles não-brancos parecem ser os mais predispostos à não-adesão. Portanto, é preciso estar alerta para sua ocorrência e, caso necessário, implementar medidas que busquem aumentar o grau de adesão destes pacientes. / CONTEXT: Non-adherence to therapy, in any degree is a common event and occurs in several circumstances. It is one of most common cause of fail in therapy of chronic diseases and Crohn's disease is not an exception. OBJECTIVE: To evaluate in patients with Crohn's disease the prevalence and the risk factors to non-adherence to therapy. METHODS: From July 2006, for 12 months, were included prospectively, for non-adhesion to therapy 100 patients with Crohn's disease that were assisted in a Center for Inflammatory Bowel Diseases of Universitary Hospital of Federal University of Juiz de Fora, MG, in Brazil. A modified Morisky & Green Test for Measure of Adherence to Therapy was answered by all of them. According to test the patients were classified in two groups defined as adherence and non-adherence, respectively, and the last one was separated in intentional and non-intentional adhesion. Clinical, psychological and pharmacotherapeutics variables were sought to find the factors related to non-adherence. RESULTS: Sixty four percent of total group were noticed to have a score of non-adherence to therapy according to used test and non-intentional was the most common type of behavior in such patients, and they demonstrated to be conscious of therapy. The comparison of adherent and non-adherent patients displayed a significant tendency to occurrence of non-adherence in younger (P = 0,07) and in non-white patients (P = 0,06). No correlation was observed in comparison of psychological and pharmacotherapeutics variables and non-adherence. CONCLUSIONS: In patients with Crohn's disease the prevalence of non-adherence to therapy is high (64%). The younger and non-white patients have higher propensity to non-adherence. In such circumstances efforts should be made to look for strategies to deal with this sort of people suffering from Crohn's disease, trying to increase the degree of adherence in this sort of patients.
102

Évaluation de la souche Lactococcus lactis recombinante produisant la protéine associée à la pancréatite humaine I dans le traitement de la colite induite par le DNBS et de la mucite induite par le 5-fluorouracile dans des modèles murins / Evaluation of recombinant Lactococcus lactis strain producing human Pancreatitis-associated Protein I in the treatment of DNBS-induced colitis and 5-Fluoracil-induced mucositis in mice models

Dias de Oliveira Carvalho, Rodrigo 04 November 2016 (has links)
Les maladies inflammatoires chroniques de l’intestin (MICI) regroupent la colite ulcéreuse (CU) et la maladie de Crohn (MD) qui sont des troubles intestinaux caractérisés par une inflammation chronique du tractus gastro-intestinal. Les MICI sont provoquées par un dysfonctionnement du système immunitaire de la muqueuse vers le microbiote intestinal chez les individus génétiquement prédisposés, menant à des réponses immunitaires pro-inflammatoires excessives. L'incidence de ces maladies augmente dans les pays développés et sont devenues de grands problèmes gastroentérologiques, surtout que les médicaments de traitement actuels sont associés à de graves effets collatéraux. Ainsi, les dernières recherches se concentrent sur le développement de nouvelles stratégies pour le traitement des MICI. Les probiotiques, en particulier celles qui appartiennent au groupe des bactéries lactiques (BL), se montrent capables de prévenir et de traiter les MICI en rétablissant l'équilibre du microbiote perturbé et en supprimant les réponses immunitaires pro-inflammatoires. Afin d'augmenter l’effet probiotique des BL, le clonage moléculaire et l'expression des molécules anti-inflammatoires ont été réalisés et les souches recombinantes des BL ont été évaluées comme un traitement alternatif pour les MICI. L'utilisation de ces souches, en particulier le modèle Lactococcus lactis, a montré son efficacité dans la lutte contre l'inflammation intestinale. Son administration comme thérapie pour traiter d'autres maladies inflammatoires du tractus gastro-intestinal, tels que la mucite, a également été évaluée. La mucite est un effet secondaire fréquent chez les patients subissant une radiothérapie ou une chimiothérapie qui affecte fortement leur qualité de vie. Comme pour les MICI, le traitement de la mucite est assez limité, seuls quelques médicaments et procédures décrits peuvent en effet contenir les ulcérations et l'inflammation. Par conséquent, ilest nécessaire de développer des traitementsalternatifs pour les MICI et la mucite. Le but de cette étude est de tester l'efficacité de la souche de L. lactis recombinante exprimant la protéine associée à la pancréatite I (PAP) afin de lutter contre les MICI et la mucite dans des modèles de souris. La PAP a été rapportée comme une protéine ayant des propriétés antimicrobiennes qui jouent un rôle important pour maintenir l'homéostasie intestinale. Tout d'abord, nous avons construit et confirmé l'expression de la PAP humaine par recombinant L. lactis. Ensuite, nous avons évalué l'effet thérapeutique de cette souche dans un modèle de souris de Dinitrobenzene acide sulfonique (DNBS) afin d’induire la colite. En outre, la livraison de PAP par lactocoques a protégé les animaux d’une perte de poids, de la perméabilité intestinale, et de lésions tissulaires. De plus, le traitement L. Lactis-PAP a diminué Th1 (IFN-y), Th2 (IL-4, IL-5) et Th17 (IL-17) de type-réponses immunitaires. On a également observé une expression élevée de régulation de cytokines TGF-β ainsi qu’une augmentation de la quantité de cellules T régulatrices chez les souris traitées. Les effets anti-inflammatoires des L. Lactis-PAP et des souches des produits laitiers L. lactis NZ9000 ont également été mesurés dans le modèle d'inflammation des muqueuses 5-Fluorouracil (5-FU). L'administration de L. lactis NZ9000 hébergeant le vecteur pSEC sans l'ADNc de PAP a été en mesure de prévenir les dommages histologiques, de réduire l’infiltration des éosinophiles et de la sécrétion d'IgA dans l'iléon de souris. D'autre part, L. lactis exprimant la PAP a conservé l'architecture muqueuse et a amélioré l'activité des cellules de Paneth. En même temps, nos résultats démontrent que L. lactis, exprimant PAP est une stratégie prometteuse pour traiter les MICI. En outre, la souche L. lactis NZ9000 de manière surprenante, a présenté des effets anti-inflammatoires chez les souris injectées avec du 5-FU. / Inflammatory Bowel Diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD) are complex intestinal disorders characterized by chronic inflammation of the gastrointestinal tract (GIT). IBD are caused by a deregulation of the mucosal immune system toward the native intestinal microbiota in genetically predisposed individuals, leading to excessive pro-inflammatory immune responses in the GIT. The incidence of both diseases is increasing in developed countries turning CD and UC a main gastroenterological problem as current treatment drugs are associated with serious side effects. Thus, recent research is focusing on the development of new strategies for the treatment of IBD. Probiotic bacteria especially the ones belonging to the lactic acid bacteria (LAB) group, were shown to be capable of preventing and treating IBD by restoring the balance of disrupted microbiota and suppressing pro-inflammatory immune responses. In order to increase LAB probiotic effect, molecular cloning and expression of anti-inflammatory molecules are being carried out and LAB recombinant strains are also being evaluated as an alternative treatment for IBD. As the use of these strains, especially the model Lactococcus lactis, showed to be very effective in fighting intestinal inflammation, its administration as a therapy for treating other human GIT inflammatory diseases, such as mucositis, are also being evaluated. This disorder is a common side effect of patients undergoing radiotherapy or chemotherapy that strongly affects their quality of life. Like IBD, treatment for mucositis is very limited with few medicaments and procedures described to contain inflammation. Therefore, given the need to develop alternative treatments for both IBD and mucositis, this study aimed to test theefficacy of either dairy L. lactis NZ9000 or recombinant L. lactis strain expressing Pancreatitis Associated Protein I (PAP) to fight inflammation in mouse models of IBD and mucositis. PAP has been reported as a protein with antimicrobial properties that plays important roles to keep intestinal homeostasis. Firstly, we constructed and confirmed the expression of human PAP by recombinant L. Lactis. Afterwards, we evaluated the therapeutic effect of this strain in a mice model of dinitrobenzenosulfonic acid (DNBS)-induced colitis. Moreover, PAP delivery by lactococci protected animals from weight loss, intestinal permeability, and tissue damage. In addition, L. lactis-PAP treatment decreased Th1 (IFNγ), Th2 (IL-4, IL-5) and Th17 (IL-17) type-immune responses. It was also observed a higher expression of regulatory TGF-β cytokine and increased amount of T regulatory cells in treated mice. The anti-inflammatory effects of both L. lactis-PAP and dairy L. lactis NZ9000 strains were also measured in 5-fluoracil mucositis model. We showed that this model was successfully reproduced in BALB/c mice with an induction of acute inflammation in the small bowel of animals. Administration of L. lactis NZ9000 harboring pSEC vector without the cDNA of PAP was able to prevent histological damage, reduce eosinophils infiltrate and IgA secretion in the ileum of mice. On the other hand, L. lactis expressing PAP preserved mucosal architecture and improved Paneth cells activity. Taking together, our results demonstrate that L. lactis, expressing PAP peptide is a promising strategy to treat IBD. Moreover, L. lactis NZ9000 strain, derived from dairy L. lactis MG1363, surprisingly presented anti-inflammatory effects in mice injected with 5-FU.
103

Vitamin E Forms – Bioavailability and Protective Effects on Colitis and Colon Cancer

Kilia Y Liu (6623429) 12 October 2021 (has links)
<p>Vitamin E is a natural lipophilic antioxidant contains eight structurally related forms, i.e., α-, β-, γ-, δ-tocopherols (αT, βT, γT, and δT) and corresponding tocotrienols. Recent research indicates that vitamin E forms are differentially metabolized to various carboxychromanols. Some these vitamin E metabolites have been shown to exhibit strong anti-inflammatory and anticancer effects, yet little is known about their bioavailability. Without this knowledge, it is impossible to assess the role of vitamin E metabolism in biological functions of vitamin E forms and their protective effects on chronic diseases. While αT and γT appear to improved gut health, the underlying mechanisms are not well understood. Furthermore, specific forms of vitamin E such as γT have been reported to have cancer-preventing effects, but their anticancer efficacy is relatively modest. For these reasons, this dissertation focused on the characterization of the pharmacokinetic formation of vitamin E metabolites after supplementation, and the investigation of the underlying mechanisms of the protective effect of vitamin E forms, αT and γT, on gut health, as well as anticancer efficacy of the combination of aspirin and γT on carcinogen-induced colon tumorigenesis.</p><p><br></p><p>The first project focuses on characterizing the pharmacokinetic formation of vitamin E metabolites after single dose supplementation of γ-tocopherol-rich mixed tocopherol (γTmT) and δ-tocotrienol (δTE). With our recently developed LC/MS/MS assay for quantifying vitamin E metabolites, we can simultaneously quantify the level of short-chain, long-chain, and sulfated carboxychromanols in plasma, urine, and fecal samples of supplemented animals. In this study, we investigated the pharmacokinetics including excretion of vitamin E forms and the formation of their metabolites after a single dose intragastric administration of tocopherols and tocotrienols in rats. We also measured vitamin E metabolites in the serum obtained from healthy humans after gT supplementation. In the plasma of rat, the pharmacokinetic profiles of γT and δTE are described as the following: γT, Cmax = 25.6 ± 9.1 μM, Tmax = 4 h; δTE, Cmax = 16.0 ± 2.3 μM, Tmax = 2 h. Sulfated CEHCs and sulfated 11’-COOHs were the predominant metabolites in the plasma of rat with Cmax of 0.4-0.5 μM (Tmax ~ 5-7 h) or ~0.3 μM (Tmax at 4.7 h), respectively. In 24-h urine, 2.7% of γT and 0.7% of dTE were excreted as conjugated CEHCs, the major identified urinary metabolites. In the feces, 17-45% of supplemented vitamers were excreted as un-metabolized forms and 4.9-9.2% as metabolites. The majority of metabolites excreted in feces were unconjugated carboxychromanols, among which 13’-COOHs constituted ~50% of total metabolites. Interestingly, 13’-COOHs derived from δTE were 2-fold higher than 13’-COOH from γT. Unlike rats, γ-CEHC is the predominant metabolites found in human plasma, although 11’-COOHs and 13’-COOHs (sulfated and unconjugated) were elevated by >20 folds responding to γT supplement. In this study, we found that tocopherols and tocotrienols, when taken as supplements, are mainly excreted as un-metabolized forms and long-chain carboxychromanols in feces. High fecal availability of 13’-COOHs may contribute to modulating effects on gut health.</p><p><br></p><p>The second project of my dissertation investigated the effect of vitamin E forms, αT and γT, on intestinal barrier function in a cellular model and a mouse colitis model. Inflammatory bowel diseases (IBD) are chronic idiopathic inflammatory conditions characterized by disruption of intestinal barrier integrity. Previous studies by others and us had demonstrated that vitamin E forms, αT and γT, can protect against chemical-induced colitis in animal models. However, the role of these vitamin E forms on intestinal barrier function has not been studied. Herein, we investigated the potential protective effects of vitamin E forms, αT and γT, on intestinal barrier function in a Caco-2 colon epithelial cell model and a dextran sodium sulfate (DSS)-induced colitis mouse model. In Caco-2 cells, pretreatment with 25mM αT and γT attenuated Caco-2 monolayer barrier dysfunction induced by 10 ng/mL TNF-α/IFN-γ, suggesting that these vitamin E forms protect intestinal barrier integrity in this cellular model. In male BALB/c mice, the supplementation of αT (0.05%) or γTmT (0.05%) when given 3 weeks before DSS treatment or at the same time as DSS treatment alleviated DSS-induced fecal bleeding and diarrhea symptoms in mice, and attenuated colon inflammation and colitis-associated damages. Additionally, αT and γTmT supplementation attenuated DSS-induced intestinal barrier dysfunction, as indicated by improving the level of occludin, a tight junction protein, in the colon and reducing lipopolysaccharide-binding protein (LBP) in the plasma. Furthermore, gut microbiota analysis demonstrated that αT and γTmT supplementation could modulate intestinal microbiome composition in mice with DSS treatment. DSS treatment reduced the relative abundance of Lachnospiraceae compared to healthy mice, and supplementation of αT and γT partially reversed this effect. Interestingly, the family Lachnospiraceae has been reported to decrease in IBD patients. Our study demonstrated the protective effects of vitamin E forms on intestinal barrier integrity in a cell-based model and a colitis model in mice. Furthermore, we demonstrated that these vitamin E forms caused favorable changes in the intestinal microbial population under colitis condition.</p><p><br></p><p>The third project of my dissertation evaluated the anticancer efficacy of the combination of aspirin and γT using an azoxymethane (AOM)-induced and colitis-promoted colon tumorigenesis mouse model. Extensive inflammation in the colon promotes the development of colorectal cancer (CRC). Eicosanoid production by pro-inflammatory enzymes, cyclooxygenases (COX-1 and COX-2) and 5-lipoxygenase (5-LOX) play a critical role in the initiation, progression, and invasion of CRC. Thus, nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, have been recommended for chemoprevention of CRC. However, long-term use of aspirin can cause many side effects, and the anticancer activity of aspirin is very modest. Previously, we have demonstrated that the combination of γT with aspirin prolonged the anti-inflammatory activity of aspirin and alleviated aspirin-associated adverse effects in a carrageenan-induced inflammation model in rats. Additionally, we found that the combination of γT and aspirin has stronger anticancer activity than aspirin or γT alone against HCT-116 human colorectal carcinoma cells. Therefore, we examined the anticancer effect of the combination of 0.025% aspirin and 0.05% γT against AOM-induced and DSS-promoted tumorigenesis in mice. In this study, we have found that the combination of aspirin and γT, but not aspirin or γT alone, suppressed colon tumorigenesis in mice, as indicated by 40% and 50% reduction in the multiplicity of total polyps (P < 0.05) and large adenomatous polyps (>2mm2, P < 0.05), respectively. More strikingly, the combination of aspirin and γT reduced the overall tumor area by 60% (P < 0.05). Noteworthy, the supplementation of γT also alleviated aspirin-induced stomach lesion and appeared to modulate intestinal microbial composition. Our study demonstrated that the combination of aspirin and γT has stronger anticancer activity than aspirin or γT alone while alleviates aspirin-associated adverse effect, suggesting that the combination of γT and aspirin is a more effective and safer chemopreventive agent for CRC than aspirin alone.</p>
104

Cadhérine atypique MUCDHL et maladies inflammatoires chroniques intestinales : implication dans leur pathogénie, l'évolution cancéreuse et la réponse au traitement par les dérivés 5-aminosalicylés / Atypical cadherin MUCDHL and inflammatory bowel diseases : involvement in pathogeny, evolution and response to treatment

Bersuder, Émilie 09 September 2019 (has links)
Les causes des Maladies Inflammatoire Chroniques Intestinales (MICI) restent mal comprises et il n’existe aucun traitement curatif. L’une des complications possibles des MICI est l’augmentation du risque de cancer colorectal (CCR). La cadhérine atypique MUCDHL pourrait être impliquée dans les MICI. Nous avons étudié le rôle de MUCDHL dans la pathogénie des MICI, ainsi que les mécanismes moléculaires qui restaurent son expression. Nous avons montré que l’expression de MUCDHL est diminuée dans la muqueuse intestinale inflammatoire. De plus, les 5-aminosalicylés, utilisés pour traiter les MICI et prévenir le CCR associé, augmentent son expression en stimulant celle de PPAR-γ et de CDX2 ou en inhibant celle de la β-caténine. Chez les souris Mucdhl -/-, l’absence de MUCDHL accélère et amplifie l’inflammation colique induite par le Dextran Sulfate de Sodium et retarde la réparation muqueuse. Nos données montrent l’implication de MUCDHL dans la physiopathologie des MICI et suggèrent qu’il pourrait constituer une cible thérapeutique d’intérêt. / The pathogenesis of Inflammatory Bowel Diseases (IBD) remains poorly understood and there is currently no curative treatment. In addition, patients with colonic IBD are at increased risk of colorectal cancer (CRC). The atypical cadherin MUCDHL could be involved in IBD. We studied the role of MUCDHL in the pathogenesis of IBD, as well as the molecular mechanisms that restore its expression. We have shown that MUCDHL expression is decreased in the inflammatory intestinal mucosa. In addition, 5-aminosalicylates, used to treat IBD and prevent associated CRC, increase its expression by stimulating PPAR-γ and CDX2 or by inhibiting β-catenin. In Mucdhl -/- mice, the absence of MUCDHL accelerates and amplifies colonic inflammation induced by Dextran Sodium Sulfate and delays mucosal repair. Our data show MUCDHL's involvement in the pathophysiology of IBD and suggest that it could be a therapeutic target of interest.
105

Facteurs de risque pour les maladies inflammatoires de l’intestin : caractérisation de l’impact de variants rares d’IFIH1 sur la réponse épithéliale antivirale

Pruneau, Laurie 08 1900 (has links)
Les maladies inflammatoires de l’intestin (MII), incluant la maladie de Crohn et la colite ulcéreuse, sont des maladies chroniques qui résultent d’un dérèglement de la réponse immunitaire aux microorganismes de la lumière intestinale. Des études de séquençages réalisées par le laboratoire du Dr. Rioux, avec ses collègues du International IBD Genetics Consortium ont identifié quatre variants rares, indépendants et causals pour les MII, dans le gène IFIH1. La protéine d’IFIH1 (MDA5) interagit avec certains virus à ARN, afin de déclencher une réponse antivirale de l’immunité innée. Nous avions émis l’hypothèse que ces variants dans IFIH1 diminuaient la réponse antivirale de l’épithélium intestinal, suite à une infection. Nous avons d’abord travaillé avec des lignées cellulaires lymphoblastoïdes (LCLs) obtenues à partir d’individus atteints de MII et qui sont homozygotes ou hétérozygotes composés pour ces variants, ainsi qu’à partir d’individus contrôles (IFIH1 wt). Ces LCLs ont été reprogrammées en cellules souches pluripotentes induites humaines, avant d’être différenciées en cultures épithéliales intestinales. Nos résultats ont d’abord confirmé l’impact des variants sur la structure génique et protéique (IFIH1/MDA5), dans ces modèles cellulaires. Puis, la réponse antivirale a été induite, grâce à la stimulation avec des agents (moléculaire et viral) connus pour stimulés la protéine MDA5. Nous avons démontré que ces variants dans IFIH1 induisaient effectivement une moins grande réponse antivirale, caractérisée par une plus faible expression d’IFNs, comparativement aux contrôles. Finalement, la modulation des IFNs constituerait une avenue potentiellement intéressante pour le traitement des patients atteints des MII et porteurs des variants causals. / Inflammatory Bowel Disease (IBD), including Cronh’s disease and ulcerative colitis, are chronic inflammatory diseases of the gastro-intestinal tract. IBD is associated with a disturbance of the immune response to the microorganisms of the intestinal lumen. Sequencing studies conducted by the laboratory of Dr. John Rioux, in collaboration with his colleagues of the International IBD Genetics Consortium, identified four rare and independent variants in IFIH1, associated to IBD. The protein of IFIH1 (MDA5) interacts with certain RNA viruses to trigger the innate mechanism of antiviral defense. Our hypothesis was that these IFIH1 variants decreased the intestinal epithelial antiviral response, following an infection. We first worked with lymphoblastoid cell lines (LCLs) obtained from IBD patients who are homozygotes or compound heterozygotes for the different variants, as well as from control individuals (IFIH1 wt). These LCLs were reprogrammed into human induced Pluripotent Stem Cells (hiPSCs), before being differentiated into intestinal epithelial cultures. Our results first confirmed the impact the variants on the genetic and protein structure for these models. Then, the antiviral response was triggered by the stimulation of LCLs and intestinal epithelial cells, with agents (molecular and viral) known to stimulate MDA5. We have demonstrated that these IFIH1 variants did indeed induce a lower antiviral response, characterized by lower IFNs expression, compared to control cell lines. Finally, modulation of IFNs could be an interesting avenue for the treatment of IBD patients with the causal variants.
106

Étude génétique et fonctionnelle de variantes de la région chromosomique 3p21 associée aux maladies inflammatoires de l'intestin

Lévesque, Marie-Pierre 04 1900 (has links)
Des études de liaison et d’association génétiques ont permis d’identifier certains des facteurs de risque génétiques aux maladies inflammatoires de l’intestin (MII) dans la région chromosomique 3p21. Dans cette région, le polymorphisme nucléotidique simple (SNP) codant non-synonyme du gène MST1, rs3197999, encodant pour la mutation R689C, a été associé et répliqué à la fois à la colite ulcéreuse (CU) et à la maladie de Crohn (MC). Un autre SNP, corrélé à des SNP codants non-synonymes du gène MST1R, a également été associé à la MC. Afin de déterminer si d’autres variantes des gènes MST1 et MST1R sont associés à la CU, nous avons testé pour association des SNP de ces gènes. Seul un proxy de R689C a montré un signal d’association significatif aux MII, ce qui suggère que R689C est la variante causale aux MII dans le gène MST1. En cherchant à déterminer si la région 3p21 contenait plusieurs signaux d’association mutuellement indépendants, trois SNP ont été identifiés comme possible facteurs de risque indépendants, et ont été génotypés dans des cas de CU et de MC et des témoins, puis nos résultats d’association ont été combinés à ceux provenant de trois autres cohortes indépendantes. Les trois SNP, R689C (MST1), rs6802890 et rs7629936 (CDHR4), sont associés aux MII, mais une étude d’association conditionnelle suggère qu’il existe en fait deux signaux d’association mutuellement indépendants dans la région 3p21. Le signal principal provient de R689C, une mutation de la protéine MSP. Cette protéine a un rôle dans l’inflammation chez les macrophages murins, et la migration, la cicatrisation et la survie chez les cellules épithéliales. Dans cette étude, le rôle de la MSP a été investigué dans des modèles de macrophages humains et de cellules épithéliales de côlon, et seule la phosphorylation d’AKT, un acteur dans la voie de signalisation de la survie cellulaire, a été modulée par la MSP dans nos modèles. Ce projet a donc permis d’apporter des connaissances sur les facteurs de risques génétiques aux MII dans la région 3p21, en identifiant 2 signaux d’association indépendants, et en nous informant sur le rôle de MST1, duquel provient le signal d’association principal, chez les cellules humaines. / Linkage studies and association studies allowed the discovery of some of the genetic risk factors of inflammatory bowel disease (IBD) in the chromosomal region 3p21. In this region, the non-synonymous coding single nucleotide polymorphism (SNP) rs3197999, situated in the gène MST1 and encoding for the mutation R689C, has been associated to UC and CD multiple times, and an other SNP, correlated to non-synonymous coding SNPs in the gene MST1R, has also been associated to CD. In order to verify if other variants of MST1 and MST1R are associatied to UC, we tested the association of some of their SNPs. Apart from R689C, only its proxy showed a significative association signal to IBD. It suggests that R689C might be the causal variant of IBD in the region 3p21. In the aim to determine if the region 3p21 has multiple independant association signals, 3 SNPs have been identified, from the results of a published meta-analysis of UC genome-wide association studies, as being possibly independant risk factors for UC based on their correlation. Their association to IBD and their independance have been tested by genotyping them in a cohort composed of controls, and UC and CD cases. The results of the association tests have been combined, in a meta-analysis, to the results of 3 other independent association studies. The 3 SNPs, R689C (MST1), rs6802890 and rs7629936 (CDHR4) are associated to IBD, but the results of the subsequent conditional association tests suggest that there is only 2 independant association signals in the region 3p21. The main signal is raising from R689C, a mutation of the protein MSP. According to published studies, this protein has a function in the inflammation in murine macrophages, and also in the scattering, wound healing and survival of epithelial cells. In this thesis, we investigated the role of MSP in human macrophage models and in human côlon epithelial cells, and it has been show that MSP modulates the phosphorylation of AKT, an actor in the pathway of cellular survival. This project brought some knowledges about the IBD genetic risk factors in the region 3p21. We identified 2 independent association signals to IBD in this region, and the main signal is coming from a SNP in MST1, a gene which has a role, based on our results, in the survival in human colon epithelial cells.
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Ultrazvučna dijagnostika upalnih oboljenja creva u komparaciji sa magnetnom rezonancom u dečjem i adolescentnom dobu / Ultrasound diagnosis of inflammatory bowel disease in comparison with magnetic resonance imaging in children and adolescence

Jecković Mihajlo 28 September 2016 (has links)
<p>UVOD: Hronične inflamatorne bolesti se ispoljavaju kao Kronova bolest i ulcerozni kolitis. Njihova značajnost ogleda se u hronicitetu kao i u stepenu u kom ograničavaju rast i razvoj dece i omladine. Brojne su posledice ovih oboljenja: dugotrajno izostajanje sa nastave, ograničavanje životnih aktivnosti i pojava komplikacija koje neretko zahvataju i druge organske sisteme. Etiologija je i dalje nerazja&scaron;njenja navodeći kao značajan hronični inflamatorni proces u genetski uslovljenih pojedinaca a provociranih nekim infektivnim agensom. Početkom 21. veka genetska istraživanja su otkrila osnovu nasleđivanja hroničnih inflamatornih oboljenja povezanih sa NOD2 genom. Kako je u pitanju organskim sistem koji je ograničeno pristupačan kliničkom pregledu, osnovu dijagnostike čine radiolo&scaron;ke metode. Kako je potrebno sprečiti kontinuirano izlaganje &scaron;tetnom dejstvu rendgenskog zračenja istraživanja se usmeravaju ka UZ i magnetnoj rezonanca. Na&scaron;e istraživanje se baziralo na mogućnostima ovih dveju metoda u svakodnevnom radu za dijagnostiku i dalje praćenje hroničnih inflamatornih bolesti creva. CILJEVI: Utvrditi senzitivnost i specifičnost ultrazvučne dijagnostike i magnetne resonance kod upalnih oboljenja creva u dečjem i adolescentnom uzrastu. Definisati i uporediti prednosti i ograničenja ultrazvučne dijagnostike sa dijagnostikom magnetne rezonace kod upalnih obolenja creva u dečjem i adolescentnom uzrastu. MATERIJAL I METODE: U istraživanje je uključeno 62. dece i adolescenata u toku prvog ataka bolesti ili ponovljenim fazama bolesti ili tokom redovnog praćenja u remisiji. Obuhvaćeni uzrast je od 4. do 18. godina. Potom su razvrstani u grupe na osnovu vrste pregleda i prisustva zadebljanja crevnog zida na A i B (pregled UZ), gde je A grupa imala zabeleženo zadebljanje crevnog zida preko 3 mm, a kod dece u grupi B debljina crevnog zida je bila između 2,5-3 mm. Sa druge strane na osnovu pregleda magnetnom rezonancom podeljeni su u A1 i B1 grupe, takođe po kriterijumu zadebljanja crevnog zida većeg od 3 mm (A1), odnosno između 2,5-3 mm (B1). Istraživanje je sprovedeno na Institutu za zdravstvenu za&scaron;titutu dece i omladine Vojvodine i Institutu za radiologiju Kliničkog centra Vojvodine. Prvi pregled načinjen je UZ a potom je načinjen pregled magnetnom rezonanacom. Podaci su obrađivani retrospektivno i prospektivno. Kriterijumi za uključivanje u studiju pored uzrasta bili su radiolo&scaron;ki: zadebljanje crevnog zida &gt;3mm, postojanje naru&scaron;ene arhitektonike crevnog zida, zadebljanje pojedinih crevnih segmenata-dužina segmenta, znaci fibroze, odsustvo peristaltike, izražena hiperemija na kolor Doppleru, transmuralni znaci upale, uvećani mezenterijalni limfni nodusi kao i kontrolni pregledi kod dece sa ranije ustanovljenom dijagnozom. Načinjena je endoskopija sa biopsijom radi postavljanja definitivne dijagnoze, potom se pristupilo statističkoj obradi dobijenih podataka. Izračunate su prosečne i standardne devijacije i frekvencije kao i pripadajući procenti. Određivane su maksimalne i minimalne vrednosti, medijane i interkvartalni raspon. Dobijeni podaci prikazani su u grafikonima i tabelama. Za parametrijske varijable upotrebljavan je Man &ndash; Vitni U test. Za kategoričke vrednosti upotrebljeni su &chi;2 i Fi&scaron;erov test. Nadalje su određivane senzitivnost, specifičnost kao i pozitivne i negativne prediktivne vrednosti. Veze između dva parametra uspostavljene su pomoću Pirsonove korelacione analize i linearnim regresionim modelom. Upotrebljen je program za obradu podataka SPSS 21 Statistics,a kao statistički značajne vrednosti uzete su vrednosti p&lt;0,05. REZULTATI: Nakon statističke obrade nije zabeležena signifikantnost u pogledu zastupljenosti hroničnih inflamatornih bolesti među polovima. Statistička značajnost pronađena je u pogledu uzrasta dece u akutnoj fazi kao i remisiji bolesti. Statistička značajnost je dobijena za posmatranu debljinu crevnog zida, hiperemiju creva, prisustvo fibroze u digestivnom traktu. Primećeno je da UZ bolje razgraničava decu sa akutnim oboljenjem po pitanju zahvaćenosti segmenata. Ostala posmatrana obeležja nisu nakon statističke obrade imala statistički značaju razliku kada se procenjuju ultrazvučno ili magnetnom rezonancom. ZAKLJUČAK: Inicijalne hipoteze ovog istraživanja su nakon obrade podataka i potvrđene. Određivanjem senzitivnosti i specifičnosti UZ i MR dobijene su sledeće vrednosti: senzitivnost UZ je 88,4% naspram 92,3% koliko ima pregled magnetnom rezonancom. U pogledu specifičnosti UZ ima 88% a magnetna rezonanca 91,6%. Verifikovano je da magnetna rezonanca bolje razvrstava decu u akutnoj fazi bolesti kao i decu u remisiji. Rezultati pozitivnih i negativnih verovatnoća odnosa ne predviđaju neuspeh nijednim od ova dva pregleda.</p> / <p>INTRODUCTION: Chronic inflammatory diseases are manifested through two clinical entities: Crohn&#39;s disease and ulcerative colitis. Their significance lies in the chronicity and the degree to which they restrict the growth and development of children and youth. There are many consenquences that come with the very nature of the disease, in addition to long-term absence from school, limiting life activities and the occurrence of complications that often affect other organ systems. The etiology of the disease has long been in favor of the theory that a chronic inflammatory process in genetically conditioned individual is provoking an inflammation due to a certain infectious agent. However, a step closer was made regarding the etiology of the disease - when the genetic basis of inheritance studies have revealed chronic inflammatory bowel diseases were associated with NOD2 gene. It is particularly important to prevent continuous exposure to the harmful effects of X-rays. Therefore, numerous studies have been made towards the validation of complementarity, accuracy and diagnostic capabilities of ultrasound and magnetic resonance imaging as noninvasive techniques. Our research was based on the capabilities of these two methods in their daily work for diagnosis and follow-up of chronic inflammatory bowel disease. OBJECTIVES: The objectives were to determine the sensitivity and specificity of ultrasound and magnetic resonance imaging in inflammatory bowel disease in children and adolescents. Furthermore, the aim was to define and compare the advantages and limitations between ultrasound diagnosis and magnetic resonance in inflammatory bowel disease in children and adolescents. MATERIAL AND METHODS: The study included 62 children and adolescents during the first attack of disease or recurrent stages of the disease, or during regular monitoring in remission. Patients included children of both sexes, aged 4-18. Then they were sorted into groups based on the type of the examination and the presence of a thickening of the intestinal wall into groups A and B - in these groups children were examined by ultrasound, A group had observed thickening of the intestinal wall &gt; 3 mm whereas children in group B had had thickening of the intestinal wall between 2,5-3 mm. Based on the review of MRI children were divided into groups A1 and B1, also according to the criterion of bowel wall thickening greater than 3mm (A1) and between 2,5-3mm (B1). The research was conducted at the Institute for Health Protection of Children and Youth and the Institute of Radiology, Clinical Center of Vojvodina. The first review was made by ultrasound, followed by the review of magnetic resonance. Data were analyzed retrospectively and prospectively. Criteria for inclusion in the study were: thickening of the intestinal wall greater than 3 mm, the existence of disturbed intestinal wall architectural structure, no clear distinction of layers, abnormal thickening of certain intestinal segments, signs of fibrosis, the absence of peristalsis, expressed hyperemia on color Doppler, transmural inflammation, increased mesenterial lymph nodes as well as check-ups for children with previously established diagnosis. Endosccopy with biopsy has made for the definitive diagnosis and then we approached statistical analysis of the data obtained. The data are presented in graphs and tables. For parametric variables we used Man - Whitney U test. For categorical values &chi;2 and Fisher&#39;s test were used. Further the sensitivity, specificity and positive and negative predictive values were determined. Relationship between these two parameters were established using Pearson correlation analysis and linear regression model. For data processing we used the program SPSS Statistics 21, statistically significant values were taken p values &lt;0.05. RESULTS: After statistical analysis there was no for the number of chronic inflammatory diseases between the sexes. Statistical significance was found in terms of age of the children during the acute phase as well as remission. Statistical significance was obtained for the observed thickness of the intestinal wall, intestinal hyperemia, the presence of fibrosis in the digestive tract. It was noted that US better demarcates children with acute disease in terms of involvement of segments. Other features are not observed as significant after the statistical analysis. CONCLUSION: The initial hypothesis of this study, after data processing were confirmed. By determining the sensitivity and specificity of ultrasound MRI results we came to the following results: sensitivity of ultrasound was 88,4% versus 92,3%, for magnetic resonance. In terms of specifics UZ has a 88% and 91,6% of magnetic resonance imaging. The classification of children in the acute phase of the disease as well as children in remission was better when MRI was used. The results of positive and negative predictions do not predict the probability of failure in neither of these methods.</p>
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Effets d'un ingrédient à base de germe de soja (Glycine max (L.) Merrill) fermenté sur l'intégrité de la barrière intestinale et la sensibilité viscérale : mécanismes d'action impliqués / Effects of a fermented soy germ ingredient(Glycine max (L.) Merrill) on intestinal barrier integrity and visceral sensitivity : mechanisms of action involved

Moussa, Lara 06 November 2012 (has links)
La barrière intestinale est la plus grande surface de contact entre le milieu extérieur et le milieu intérieur. Outre ses fonctions d'absorption des nutriments, elle exerce un rôle important de défense contre les agents indésirables (toxines, bactéries) contenus dans la lumière intestinale. Une augmentation de la perméabilité intestinale a été observée chez les patients atteints du syndrome de l'intestin irritable (SII) ou des maladies inflammatoires chroniques de l'intestin (MICI). Cette hyperperméabilité intestinale est contemporaine d'une hypersensibilité viscérale à la distension de la paroi intestinale. Des travaux récents rapportent également une augmentation de l'activité protéolytique du contenu intestinal dans le cadre de ces deux pathologies. Les estrogènes, par leurs propriétés anti-inflammatoires et leur capacité à moduler la perméabilité intestinale par activation de leurs récepteurs (REs) peuvent contribuer à l'amélioration des symptômes associés à ces pathologies digestives. Une variété de traitements médicaux a été utilisée pour la prise en charge thérapeutique du SII et de MICI. Cependant, les patients questionnent les cliniciens sur des conseils diététiques susceptibles d'améliorer leur qualité de vie. Ainsi, l'objectif de ce travail était d'évaluer les effets et les mécanismes d'action impliqués, d'un traitement par du germe de soja fermenté (SG) sur l'hyperalgésie viscérale et l'hyperperméabilité intestinale dans des modèles animaux mimant le SII et les MICI afin de proposer des futures allégations santé à ce produit. Le rationnel de l'évaluation de cet ingrédient était basé sur sa composition intéressante, à savoir, sa teneur en composés à propriétés estrogéniques (isoflavones) et sa capacité à inhiber les protéases (BBI). Dans un premier temps, nous avons montré qu'un traitement oral de 15 jours par le SG diminue de façon significative l'hypersensibilité viscérale, l'hyperperméabilité intestinale ainsi que l'augmentation de l'activité protéolytique induites par un stress de contrainte chez le rat. La diminution de la perméabilité intestinale implique une surexpression de l'occludine, protéine des jonctions serrées. De même, le traitement par du SG réduit la densité des mastocytes au niveau du côlon. Tous les effets préventifs du SG sauf ceux sur l'activité protéolytique sont estrogéno-dépendants car bloqués par l'antagoniste des REs. Dans un second temps, nous avons montré qu'un traitement préventif par le SG pendant 15 jours présente des effets protecteurs vis-à-vis d'une inflammation intestinale induite par du TNBS. Le SG atténue la sévérité de l'inflammation, l'hyperperméabilité, l'hypersensibilité et l'augmentation de l'activité protéolytique induites par la colite. Les effets anti-inflammatoires du SG sont à la fois dépendants des phytoestrogènes et du contenu de l'ingrédient en BBI. En conclusion, ces données sont prometteuses pour une future utilisation du SG dans la gestion thérapeutique du SII et des MICI comme traitement adjuvant / The intestinal barrier is the largest area of contact between the external environment and internal environment. In addition to its function of nutrient absorption, the intestinal barrier plays a key role of defense against noxious agents (toxins, bacteria) contained in the intestinal lumen. An increase in intestinal permeability was observed in patients with irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). This intestinal hyperpermeability was often associated with visceral hypersensitivity to colorectal distension. Recent studies also report an increase in the proteolytic activity in patients with IBS or IBD. Estrogens, through their anti-inflammatory properties and their ability to modulate intestinal permeability by activating estrogen receptors (ERs), can play an important role in these digestive diseases. A variety of medical therapies have been used for treatment of IBS and IBD. However, patients question clinicians about dietary suggestions to improve their symptoms and quality of life. Thus, the aim of this study was to evaluate the effects and mechanisms of action involved of a treatment with fermented soy germ (SG) on visceral hyperalgesia, intestinal hyperpermeability in animal models mimicking the IBS and IBD. The evaluation of this ingredient was based on its interesting composition, i.e its content of isoflavones and a family of serine protease inhibitors known as BBI. Initially, we demonstrated that an oral treatment of 15 days by SG significantly reduces visceral hypersensitivity, intestinal hyperpermeability and increased proteolytic activity induced by acute stress in the rat. Decreased intestinal permeability is due to overexpression of occludin, a transmembrane tight junction protein. Similarly, treatment with SG reduces the density of colonic mast cells. All preventive effects of SG except those on the proteolytic activity are estrogen-dependent because blocked by the antagonist of ERs. In a second step, we demonstrated that a treatment for 15 days with SG induces protective effects against intestinal inflammation induced by TNBS. SG reduces the severity of colitis, decreases TNBS-induced hyperpermeability, hypersensitivity and increased proteolytic activity. The anti-inflammatory effects of SG are estrogen and/or BBI dependent. In conclusion, these data are promising for future use of the SG as adjuvant therapy in IBS and IBD management
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Comparação entre a colonoscopia com cromoscopia e com o NBI para detecção de displasia e neoplasias colônicas em pacientes com doença inflamatória intestinal de longa data: estudo randomizado e controlado / Comparison between colonoscopy with chromoendoscopy and NBI for the detection of colonic neoplasia and dysplasia in patients with inflammatory bowel disease of long standing: a randomized controlled trial

Feitosa, Flávio de Castro 14 May 2013 (has links)
Introdução: Pacientes com doença inflamatória intestinal (DII) tem risco aumentado de desenvolvimento de displasias e neoplasias colônicas, a partir de 8 anos de diagnóstico da doença. O desenvolvimento de técnicas que melhorem a acurácia diagnostica destas displasias tem impacto científico, econômico e na prática clínica. Materiais and Métodos: O NBI (narrow band image) tem sido descrito como um método comparável à cromoscopia para a detecção de diversos tipos de cânceres do trato gastrointestinal superior e do sistema respiratório. Neste estudo, as duas técnicas foram comparadas em pacientes com DII de longa data. Resultados: 34 pacientes foram randomizados (18 para a cromoscopia e 16 para o NBI). 66,7% e 68,8% dos pacientes eram do gênero feminino, com média de idade de 48,5 e 49,6 anos, nos grupos cromoscopia e NBI, respectivamente. 61,1% dos pacientes do grupo cromoscopia e 56,2% do grupo NBI tinham doença de Crohn (DC). Nenhuma destas variáveis alcançou diferença estatísticamente significante na comparação entre os grupos: comportamento da DC, localização da retocolite ulcerativa, presença de atividade inflamatória endoscópica e sintomas no momento do exame. O tempo médio gasto para a realização do exame foi de 45,8 minutos no grupo cromoscopia e de 34,1 minutos no grupo NBI. Sobre a presença de displasias, 22,2% dos pacientes no grupo cromoscopia apresentaram lesões displásicas no exame histológico (todas as biopsias foram direcionadas pela presença de lesões), enquanto que, no grupo NBI, nenhuma lesão displásica foi encontrada (qui-quadrado= 4,477; &#8721;crítico> 3,841, considerando um erro a de 5%). Foram encontrados três lesões adenomatosas e uma lesão displásica tipo DALM (dysplasia-associated lesion or mass), típica da DII. Quando realizada a correção de Yattes, ara amostras pequenas, foi observado &#8721; = 2,180 (&#8721;crítico> 3,841, considerando um erro a de 5%). Conclusões: Esses dados mostram diferença estatística entre as técnicas endoscópicas (NBI e cromoscopia). Eles revelam uma forte tendência estatística de superioridade da cromoscopia, comparada ao NBI. / Introduction: Patients with inflammatory bowel disease (IBD) are under increased risk of colonic dysplasia and neoplasia, approximately, 8 years after diagnosis. The development of techniques that improve the diagnostic ability to detect those dysplasias has scientific, economic and practical impact. Materials and Methods: The NBI (narrow band image) has been described as a valuable method comparable to chromoendoscopy for the detection of many cancers of the upper digestive and respiratory systems. The two techniques were compared in this study in patients with IBD after at least 8 years from diagnosis. Results: 34 patients were randomized (18 for chromoendoscopy and 16 for NBI). 66.7% and 68.8% were female, mean age of 48.5 and 49.6 years, in chromoendoscopy and NBI groups, respectively. The mean disease duration was 14.7 (DP 6.5 years 2) and 15.6 years (DP 9.0 years 2) for chromoendoscopy and NBI, respectively. 61.1% of patients in the chromoendoscopy group and 56.2% in the NBI had Crohn\'s disease (CD). None of those epidemiological data, extension and behavior of CD and Ulcerative Colitis, use of medications, endoscopic grade of disease activity and symptoms at the time of the exam disclosed statistical significance. The average time of examination was 45.8 minutes for the chromoendoscopy group, versus 34.1 minutes for the NBI group. Regarding the presence of dysplasia, 22,2% of patients in the chromoendoscopy group showed some dysplastic lesions on histological examination (all biopsies directed to mucosal lesions), while no patients in the NBI group had such lesions (chi-square = 4.477; &#8721;critical> 3.841, considering an error of 5%). We found three adenomas and one dysplastic lesions of the type DALM (dysplasia-associated lesion or mass), typical of IBD. When we look at correcting by means of the Yates correction test for small samples, we observed &#8721; = 2,180 (&#8721;critical > 3.841, considering an error of 5%). Conclusion: Those data have shown statistical difference between the endoscopic techniques (NBI and chromoendoscopy). They revealed a strong statistical tendency of superiority of chromoendoscopy compared to NBI.
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PET molecular imaging of peripheral and central inflammatory processes targeting the TSPO 18 kDa / Imagerie Moléculaire du processus inflammatoire périphérique et central par TEP des en ciblant le TSPO 18kDa

Bernards, Nicholas 01 October 2014 (has links)
L’objectif de la thèse: À ce jour, il est admis que la TSPO joue un rôle important dans le processus inflammatoire, et qu’il est possible de suivre sa présence à l’aide d’une variété de radiotraceurs adaptés. Les impacts de l’inflammation touchent un grand nombre de personnes à travers le monde pour diverses raisons ; c’est pourquoi, quoique le [ ¹ ⁸F]DPA-714 est très prometteur, il est nécessaire d’aller plus loin pour explorer ses capacités et ses applications possibles. L’inflammation a une forte incidence sur différentes maladies, par conséquent, à impact social élevé (comme la maladie inflammatoire de l’intestin (IBD), la neuroinflammation, et le choc septique). Dans ces modèles nous analyserons et quantifierons les niveaux de d’expression de TSPO 18kDa par imagerie TEP que nous comparerons au niveau exprimé trouvés chez des sujets contrôles. L’objectif étant de déterminer si la TSPO peut constituer une cible biologique d’intérêt pour l’évaluation et la quantification d’un état inflammatoire chez l’individu en utilisant l’imagerie TEP avec le radioligand [ ¹ ⁸F]DPA-714.Aperçu sur le travail de recherche : L’étude entreprise dans cette thèse a fourni des informations conduisant à la conclusion suivante : la TSPO 18kDa peut en effet être utile comme biomarqueur pour l’évaluation d’un état inflammatoire dans plusieurs maladies. Nous avons pu illustrer par l’intermédiaire de deux modèles de la maladie inflammatoire de l’intestin, un modèle de la neuroinflammation et un modèle de choc septique, que la TSPO est un indicateur du niveau de l’inflammation dans la zone affectée. De plus, nous avons pu suivre, mesurer et quantifier l’évolution d’une zone inflammée en fonction du temps.Bien que le [ ¹ ⁸F]DPA-714 est le traceur utilisé pour déterminer la présence et le niveau de l’inflammation, d’autres traceurs sont constamment en cours de développement. Cela est démontré par le travail de collaboration effectuée avec l’équipe de radiochimie, dans lequel nous avons illustré le potentiel d’un nouveau radioligand de TSPO, le [ ¹ ⁸F]DPA-C5yne. / Purpose : The purpose of this study was to determine the in vivo potential of the TSPO 18 kDa as a biomarker of inflammation, with the use of its radioligand [ ¹ ⁸F]DPA-714, to non-invasively quantify the inflammatory state within the scope of various pathologies. Procedure : Multiple animal models of various inflammatory diseases, to include : inflammatory bowel disease, neuroinflammation, and septic shock, were developed and put in place by adapted measures. The animals well-being and the subsequent inflammation was evaluated. The inflammatory state was measured using quantitative PET imaging with the TSPO radioligand [ ¹ ⁸F]DPA-714 and correlated to the expression of conventional inflammatory markers using microscopy. Results : Based on the observed data, we were able to distinguish control groups from treated groups when using [ ¹ ⁸F]DPA-714. This TSPO radioligand permitted us to quantify the inflammatory level and to observe evolutionary changes in the inflammatory state of the disease in multiple models. The PET results, using the [ ¹ ⁸F]DPA-714 signal was correlated with an increased TSPO expression at cellular level. Conclusion : Results indicate that [ ¹ ⁸F]DPA-714 is a suitable tracer for studying inflammation of multiple diseases.[ ¹ ⁸F]DPA-714 could be a good molecular probe to non-invasively evaluate the level and localization of inflammation. Moreover, in vivo imaging using this TSPO ligand is potentially a powerful tool to stage and certainly to follow the evolution and therapeutic efficiency at molecular level in inflammatory diseases.

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