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Déterminants génétiques du métabolisme des monocarbones : approche gène candidat dans deux populations ambulatoires et étude d'association avec la maladie de Crohn / Genetic determinants of one carbon metabolism : candidate gene approach in two ambulatory populations and genome association study in patients with Crohn's diseaseOussalah, Abderrahim 31 October 2011 (has links)
Des études d'associations pangénomiques ont démontré une relation entre le taux plasmatique de la vitamine B12 et le polymorphisme du gène FUT2 (fucosyltransferase 2). Dans des modèles expérimentaux, le statut sécréteur pour FUT2 a été impliqué dans la susceptibilité à l'infection par Helicobacter pylori (H. pylori). Nous avons évalué l'influence du polymorphisme FUT2 461 G>A sur les marqueurs du métabolisme des monocarbones dans deux populations ambulatoires en Europe et en Afrique de l'Ouest ainsi que la possible association entre l'infection par H. pylori et le polymorphisme de FUT2. Nous avons mis en évidence une influence de FUT2 461 G>A sur le taux plasmatique de la vitamine B12 mais n'avons pas retrouvé d'influence du statut sérologique pour H. pylori sur cette association, du moins chez les sujets ambulatoires en Europe et en Afrique de l'Ouest. L'hyperhomocystéinémie est un marqueur de carence en donneurs de méthyle. Plusieurs travaux ont évalué le taux plasmatique de l'homocystéine au cours des maladies inflammatoires chroniques de l'intestin (MICI) et ont abouti à des résultats mitigés. Par ailleurs, l'ampleur de l'association entre le métabolisme de l'homocystéine et les MICI reste méconnue. Nous avons réalisé une méta-analyse afin : (i) d'évaluer l'association entre le métabolisme de l'homocystéine et les MICI et (ii) d'étudier le risque de thrombose lié à l'hyperhomocystéinémie au cours des MICI. Le risque d'hyperhomocystéinémie était significativement plus élevé chez les patients avec une MICI en comparaison aux sujets contrôles. L'évaluation du risque de thrombose associé à l'hyperhomocystéinémie au cours des MICI requiert des études complémentaires. Un statut carencé en folates était associé à un impact plus fort du polymorphisme MTHFR C677T sur le risque primaire de MICI. L'hyperhomocystéinémie et plusieurs polymorphismes sur les gènes du métabolisme des monocarbones sont associés au risque primaire et à la sévérité de la maladie de Crohn (MC). L'hyperhomocystéinémie augmente l'activité de la superoxyde dismutase (SOD), un marqueur fiable et validé du stress oxydatif. A l'aide d'un SNP array Illumina exhaustif du métabolisme des monocarbones, nous avons (i) étudié les déterminants génétiques (single nucleotide polymorphisms, SNPs) associés au taux plasmatique de l'homocystéine et de la SOD chez des patients suivis pour une MC et (ii) recherché les SNPs associés à l'âge du diagnostic de la MC. Deux SNPs étaient indépendamment associés au taux plasmatique de l'homocystéine (MTHFR, AHCY). Cinq SNPs étaient indépendamment associés au taux plasmatique de la SOD. Parmi ces cinq SNPs, trois sont liés à la vitamine B12 (FUT2, CUBN, et TCN2), un aux folates (GGH), et un dernier à la synthèse cellulaire de l'homocystéine (AHCY). Par ailleurs, nous avons mis en évidence deux SNPs associés à un âge précoce du diagnostic de la MC (CHDH, ABCB1). / Genome wide association studies demonstrated an association between plasma vitamin B12 and FUT2 (fucosyltransferase 2). It has been suggested that the association between FUT2 and low plasma vitamin B12 level may be the consequence of an increased susceptibility to Helicobacter pylori (H. pylori) infection. We evaluated the association between FUT2 461G>A polymorphism and vitamin B12 and investigated whether the influence of FUT2 on H. pylori serology is part of the mechanisms that underlie this association, in two populations from Europe and West Africa. In this study we confirmed the influence of FUT2 461 G>A polymorphism on plasma vitamin B12 level and found no influence of H. pylori serological status on this association, at least in ambulatory subjects from Europe and West Africa. The magnitude of the association between homocysteine metabolism and inflammatory bowel diseases (IBD) is unknown while the association between hyperhomocysteinemia and thrombosis remains controversial in IBD. We conducted a systematic review of the literature and performed a meta-analysis to examine these issues. The risk of hyperhomocysteinemia is significantly higher in IBD patients when compared to controls. The risk assessment of hyperhomocysteinemia-related thrombosis in IBD requires further investigation. Deficient folate status is associated with a higher impact of MTHFR C677T polymorphism on IBD risk. Hyperhomocysteinemia and several gene variants of one-carbon metabolism are associated with the occurrence and severity of Crohn's disease (CD). Hyperhomocysteinemia results in part from methyl donors deficiency - which is frequent in patients with CD - and increases the activity of superoxide dismutase (SOD), a validated and reliable marker of oxidative stress. We designed a 384-plex GoldenGate oligo pool assay for the comprehensive one-carbon metabolism genotyping using Illumina platform. The aims of this study were (i) to assess genetic determinants of plasma homocysteine and superoxide dismutase (SOD) levels in patients with IBD and (ii) to look for single nucleotide polymorphisms (SNPs) associated with age at CD onset. Two SNPs were associated with plasma homocysteine level (MTHFR, AHCY). Five SNPs were independently associated with plasma SOD level. Of these five SNPs, three are related to vitamin B12 (FUT2, CUBN, and TCN2), one is related to folate (GGH), and the last one to homocysteine (AHCY). In addition, we identified two SNPs associated with early CD onset (CHDH, ABCB1)
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A galectina-3 na fisiologia e no câncer de tiróide: identificação de SNPs no gene LGALS3 e estudo funcional de galectina-3 in vitro e in vivo / Galectin-3 in thyroid physiology and cancer: identification of SNPs in the LGALS3 gene and functional study of galectin-3 in vitro and in vivo.Martins, Luciane 17 April 2008 (has links)
Neste estudo, investigamos o envolvimento de galectina-3 na fisiologia e no câncer de tiróide usando vários modelos biológicos e metodologias. Observamos que o gene LGALS3 apresenta um SNP no códon 98, mas não observamos correlação entre os genótipos deste SNP e fenótipo de câncer de tiróide. Na linhagem de tiróide de rato PCCl3, mostramos que a indução da expressão do oncogene RET/PTC promove o aumento da expressão de galectina-3, no entanto, a expressão de galectina-3, por si só, não confere vantagem de proliferação à célula. Por outro lado, na linhagem de carcinoma papilífero de tiróide TPC-1, a galectina-3 contribui para a sobrevivência da célula tumoral e progressão do ciclo celular, aumentando a expressão de c-Myc, diminuindo a expressão de p21 e caspase-3, e favorecendo a ativação de importantes vias envolvidas no controle do ciclo celular. Além disto, em modelos in vivo e in vitro, a galectina-3 interferiu na função e diferenciação da célula folicular tiroidiana, exercendo um papel indireto na regulação da expressão da tireoglobulina e atividade de TTF-1. / In this study, we investigate the involvement of galectin-3 in thyroid physiology and cancer using several biological models and methodologies. We observed that LGALS3 gene presents a SNP in codon 98, but no correlation between the genotype and the phenotype of benign or malignant thyroid tumor was observed. In the rat thyroid cell line PCCl3, we showed that the conditional induction of RET/PTC oncogene expression promotes the increase of galectin-3 expression, however, galectin-3 expression itself did not confer a proliferative advantage to cell. On the other hand, in papillary thyroid carcinoma cell line TPC-1 the galectin-3 contributes to tumor cell survival and cell cycle progression, increasing c-Myc expression, decreasing p21 and caspase-3 expression and cooperating to activation of important signaling pathways which are involved in the cell cycle control. In addition, in vitro and in vivo models the galectin-3 interferes in the differentiation and function of thyroid follicular cell, playing an indirect role in the regulation of thyroglobulin expression and TTF-1 activity.
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Estudos dos polimorfismos dos genes GSTT1, GSTM1 e NINJURIN1 em indivíduos com Hanseníase.Graça, Carla Renata 26 July 2011 (has links)
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Previous issue date: 2011-07-26 / Leprosy is a chronic infectious disease caused by Mycobacterium leprae (M. leprae), an obligate intracellular acid-fast bacillus, which affects the skin and
peripheral nervous system. The diseases expression results from the interaction between the bacillus and the immune system; most infected subjects develop effective immune response against M. leprae, without disease; others exhibit a spectrum of clinical manifestations closely linked to the pattern of host immune response to pathogen. Among the host defense mechanisms are immunoregulatory cytokines with activities
represented by specific populations of Th1 and Th2 lymphocytes and the production of reactive oxygen species (ROS), which are key elements for bacterial destruction intramacrofágica. In this context, several genomic regions have been implicated in
susceptibility and severity in genetically controlled leprosy. The glutathione Stransferase are enzymes that eliminate reactive oxygen species, are the most studied
genes: GSTM1 and GSTT1. The NINJURIN1 is a cell adhesion molecule that provides suitable substrates for repair of Schwann cells after peripheral nerve injury. The single nucleotide polymorphism NINJ1, encoded by the protein NINJURIN1, is the result of a transversion to adenine nucleotide polymorphic cytokine (AC), responsible in an amino acid exchange of asparagine for alanine at position 110 of the protein (asp110ala). Objectives. 1) Investigate if the presence of polymorphism in the GSTT1 and GSTM1 genes could affect the course of leprosy; 2) Investigate if the presence of polymorphism in the NINJ1 gene could be relevant for neural impairment. Material and Methods. A cohort of 218 leprosy patients (patients) and 244 subjects without leprosy (controls) was studied. The genomic DNA was obtained from peripheral blood, GSTT1 and GSTM1 polymorphism screening was performed using polymerase chain
xi Abstract v reaction and NINJ1 gene analysis was performed using the technique of restriction
fragment length polymorphism (PCR-RFLP) using the enzyme Hae III. The genotype and allele frequency were measured by Chi-square and logistic regression models with or without correction for age and gender. Results. The frequency of the GSTT1/GSTM1 null genotypes was significantly higher in controls when compared to
patients (P = 0.01). The GSTT1 genotype frequency was significantly increased in patients when compared to controls (P=0.01). The frequency of the NINJ1 asp110ala
was significantly increased in patients with nerve impairment (p = 0.0198). Also, patients with the CC (ala/ala) allele had a higher risk of developing disability when compared the allele AA (asp/asp) (p = 0.0143). Conclusion. The results demonstrated: (1) there is an association of GSTT1 positive genotype for development of leprosy disease. The data found suggested that the absence of GSTs, with a consequent permanence of intracellular ROS, can contribute to M. leprae destruction and, therefore, reduce the disease risk; (2) polymorphism in NINJ1 gene offers less nerve protection in leprosy patients. This finding indicates that NINJURIN1 is an important adhesion molecule and can be a potential therapeutic tool in many diseases. / A hanseníase é uma doença infecciosa crônica causada pelo bacilo álcool-ácido resistente Mycobacterium leprae (M. leprae), patógeno intracelular obrigatório, que afeta a pele e o sistema nervoso periférico. A expressão dessa doença resulta da interação entre o bacilo e o sistema imunológico; a maioria das pessoas infectadas desenvolve resposta imune eficaz contra M. leprae, sem sintomas da doença; outras exibem um espectro de manifestações clínicas ligado ao padrão da resposta imunológica do hospedeiro ao patógeno. Entre os mecanismos de defesa do hospedeiro estão as citocinas com atividades imunorreguladoras específicas representadas pelas
populações de linfócitos Th1 e Th2 e a produção de espécies reativas de oxigênios (ROS), que são elementos fundamentais para destruição bacilar intramacrofágica. Nesse contexto, inúmeras regiões genômicas têm sido implicadas na suscetibilidade e na severidade geneticamente controlada à hanseníase. Os Glutatião S-transferase são enzimas que eliminam as espécies reativas de oxigênio, os genes mais estudados são: GSTT1 e GSTM1. O NINJURIN1 é uma molécula de adesão celular que fornece substratos apropriados para reparação das células de Schwann após lesão no nervo periférico. O polimorfismo de nucleotídeo único NINJ1 codificado pela proteína NINJURIN1, é resultado de uma transversão polimórfica do nucleotídeo adenina para citocina (AC), responsável pela troca de um aminoácido asparagina para alanina na posição 110 da proteína (asp110ala). Objetivos. 1) avaliar os polimorfismos dos genes GSTT1 e GSTM1 na modulação da suscetibilidade genética à hanseníase e/ou à
evolução dessa doença em seus pólos maligno ou benigno; 2) investigar a correlação entre o polimorfismo de nucleotídeo único NINJURIN1 e o grau de comprometimento do nervo periférico. Materiais e Métodos. A amostra foi composta de 218 pacientes xi Resumo com hanseníase (pacientes) e 244 indivíduos sem hanseníase (controles). O DNA genômico foi obtido de sangue periférico, a análise dos polimorfismos GSTT1 e GSTM1 foi realizada utilizando a técnica de reação em cadeia da polimerase (PCR) e a análise do gene NINJ1 foi realizada através da técnica de polimorfismo de comprimento de fragmento de restrição (PCR-RFLP), utilizando a enzima HAE III. A frequência de
genótipos e alelos foi analisada pelo teste do qui-quadrado e por modelos de regressão logística com ou sem correção para idade e sexo. Resultados. A frequência dos genótipos nulos GSTT1/GSTM1 foi significativamente maior nos controles que nos pacientes (P = 0,01). A frequência do genótipo GSTT1 foi significativamente maior nos pacientes em relação aos controles (P = 0,01). A frequência do polimorfismo NINJ1 asp110ala foi significativamente maior em pacientes com comprometimento do nervo (p = 0, 0198). Além disso, pacientes com o alelo CC (ala / ala) apresentaram risco maior de desenvolver lesão no nervo quando comparado ao alelo AA (asp / asp) (p = 0,0143).
Conclusão. Os resultados demonstraram: (1) há associação do genótipo GSTT1 positivo para o desenvolvimento da hanseníase. Os achados sugerem que a ausência de GSTs, com consequente permanência de ROS intracelular, pode contribuir para a eliminação do M. leprae e, dessa forma, reduzir o risco da doença; (2) o polimorfismo no gene NINJ1 oferece menos proteção ao nervo na hanseníase. Esse achado indica que
a NINJURIN1 é uma molécula de adesão importante e pode ser uma potencial ferramenta terapêutica em muitas doenças.
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Statistical Methods to Combine SPN and CNV Information in Genome-Wide Association Studies : An Application to Bladder Cancer / Utilisation conjointe de l'information apportée par les différents polymorphismes, SNPs et CNVs, dans les études d'association pangénomique : application au cancer de la vessieMarenne, Gaëlle 28 September 2012 (has links)
Les variations en nombre de copies (CNV) sont des gains ou pertes d’une séquence d’ADN et peuvent avoir un rôle dans la susceptibilité à certaines maladies. Les CNVs peuvent être détectés par les puces de SNPs de haute résolution en analysant les intensités des allèles avec des algorithmes de détection des CNVs tels que CNV partition, PennCNV et QuantiSNP. Dans cette thèse, nous avons évalué les performances de ces outils pour la détection des CNVs au niveau pangénomique et pour les tests d'association. Nous avons également étudié des stratégies d'association combinant les informations de l'allèle et du nombre de copies pour des SNP situés dans des CNV. Nous avons appliqué ces outils pour mener une étude d’association pan-génomique avec les CNV en utilisant les données de l'étude espagnole du cancer de lavessie (SBC)/EPICURO générées par la puce Illumina 1M.Nos résultats montrent une faible fiabilité et une faible sensibilité des algorithmes de détection des CNV. Dans la région du gène GSTM1 où un CNV très fréquent existe qui est associé au risque de cancer de la vessie, nous avons constaté que les algorithmes de détection des CNV ont de faibles performances. Néanmoins, l’utilisation de la mesure d'intensité des allèles dans les tests d'association peut alors être une alternative intéressante car cela nous a permis de détecter cette association connue. Pour les SNPs situés dans des CNVs, nous avons étudié plusieurs stratégies de tests d'association et nous avons montré que la plus puissante était d’utiliser un modèle avec deux termes correspondant respectivement à la somme et à la différence du nombre de copies des deux allèles. Finalement, en appliquant ces stratégies à l'étude (SBC)/EPICURO, nous avons identifié des CNVs potentiellement associés au risque de cancer de la vessie, ainsi que des SNP dont l'allèle et le nombre de copies pourraient être impliqués dans le risque de cancer de la vessie. / Copy number variations (CNVs) are losses or gains of DNA sequences that may play a role in specific disease susceptibility. CNVs can be detected by high-resolution SNP-arrays through the analysis of allele intensities with CNV calling algorithms such as CNVpartition, PennCNV and QuantiSNP. In this thesis, we identified and assessed the performances of available tools for CNV calling and for association testing, at the genome-wide level. We also investigatedassociation strategies that combine information on both the allele and the number of copies for SNPs located in CNV regions. We applied these tools to conduct a genome-wide association study with CNV using data from the Spanish Bladder Cancer (SBC)/EPICURO Study generated by the Illumina 1M SNP-array. Our results showed a low reliability and a low sensitivity of the investigated CNV calling algorithms applied to SNP-array data. The GSTM1 locus shows a very frequent CNV that is associated with bladder cancer (BC) risk. We reported that the calling algorithms performed very poorly in identifying this CNV. We proposed using allele intensity measures (LRR) as a screening step to assess association as it allowed the detection of the GSTM1 CNV association with BC. To combine the allele and the number of copies for SNPs located in CNV regions, we investigated several strategies of association testing and we showed that the more powerfulone used a two-term model with the sum and the difference of the number of copies of both alleles. Finally, by applying these strategies to the (SBC)/EPICURO Study, we identified CNV regions potentially associated with BC risk, as well as SNPs for which both the allele and the number of copies could be involved in BC risk.
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Influência do polimorfismo do gene MYH9 na doença renal progressiva em pacientes com nefrite lúpica / Influence of the MYH9 gene polymorphism in progressive kidney disease in patients with lupus nephritisColares, Vinicius Sardão 20 January 2012 (has links)
INTRODUÇÃO: A nefrite lúpica é uma complicação frequente e de alta morbimortalidade do lúpus eritematoso sistêmico (LES). A evolução para insuficiência renal crônica terminal varia entre 8 e 15% dos casos, após um período de 5 anos. A fase inicial da nefrite se deve a uma atividade imunológica exacerbada que leva a sequelas renais, como a fibrose intersticial, sinéquias glomerulares, e glomeruloesclerose. Uma vez instalada, vários fatores aceleram a velocidade de progressão da insuficiência renal, como a presença de proteinúria residual, hipertensão arterial sistêmica e a etnia do paciente. Estudos recentes mostraram que a presença de polimorfismos do MYH9 são altamente prevalentes em pacientes com GESF (glomeruloesclerose focal e segmentar), nefropatia do HIV e em pacientes com doença renal crônica não diabética. Os polimorfismos do MYH9 mais relacionados com essas doenças são os do haplótipo E1, causados pelos polimorfismos rs4821480, rs2032487, rs4821481 e rs3752462, presentes principalmente na população negra e de hispano-americanos. No Brasil não há estudos sobre a prevalência desse gene. MÉTODOS: Nosso estudo analisou retrospectivamente 196 pacientes com nefrite lúpica, acompanhadas no ambulatório de glomerulopatias do Hospital das Clínicas da USP. Foram recuperados os dados clínicos e laboratoriais dos pacientes de janeiro de 1999 a dezembro de 2010. Foi feita análise dos polimorfismos do haplótipo E1 do gene do MYH9 (rs4821480, rs2032487, rs4821481 e rs3752462) e correlacionados com suas características clínicas e laboratoriais, apresentando como desfecho a duplicação da creatinina ou a evolução para doença renal crônica terminal. RESULTADOS: O tempo de seguimento médio dos pacientes foi de 6,1 anos, com a creatinina inicial média de 1,6 g/dL e proteinúria média de 3,9 g/dia. Dezenove pacientes não recuperaram função renal, mantendo-se em diálise. Dos 177 pacientes restantes 43 (24%) apresentaram o desfecho de duplicação (DC) da creatinina, ou necessidade de diálise (DRCT). Pacientes progressores eram tinham maior SLEDAI renal (10 vs 8,9 p=0,04), maior índice de cronicidade renal à biópsia (5 vs 2, p<0,001) e maior frequência de reativações da doença renal (flare renal) (82,9% x 53,8%, p=0,002), assim menores índices de remissão completa ou parcial (p<0,0001). Os 4 polimorfismos se segregam em conjunto, ou seja, como um haplótipo, pelo modelo de Hardy-Weinberg. Analisando separadamente cada polimorfismo, apenas o rs3752462, apresenta associação com o desfecho DC/DRCT, na análise por genótipo (CC/CT/TT, p=0,03) e quando feita análise TT/CT vs CC (p=0,02). Não houve relação dos polimorfismos com a etnia negra ou parda. Pacientes com haplótipo E1 eram progressores em 28% dos casos, conferindo um OR de 1,79 (IC 1,02 a 3,0) de DC/DRC. DISCUSSÃO: A presença do haplótipo E1 têm alta prevalência em pacientes portadores de nefrite lúpica no Brasil, sendo fator de risco para progressão da doença renal crônica / BACKGROUND: Lupus nephritis (LN) is a frequent complication with high morbidity and mortality of systemic lupus erythematosus (SLE). Chronic renal failure is observed in 8 to 15% of the patients after 5 years of follow up. LN is an inflammatory disease after a systemic autoimmune activation. Once inflammation is shutdown several renal and nonrenal factors, such as residual proteinuria, hypertension and ethnicity of the patient, may emerge and impose to the kidney a chronic phenotype (interstitial fibrosis, glomerular adhesions and glomerulosclerosis. Recently E1 haplotype (rs4821480, rs2032487, rs4821481 and rs3752462 polymorphisms) of the MYH9 gene was associated to progressive kidney diseases in patients with FSGS (focal segmental glomerulosclerosis), HIV nephropathy and non-diabetic chronic kidney disease, in african american and spanic american patients. In Brazil there is no data on this subject. METHODS: Retrospective analysis of 196 patients with LN followed in our outpatient glomerular disease ward were enrolled glomerulopathies. Patients clinical data from January 1999 to December 2010 were retrieved and MYH9 rs4821480, rs2032487, rs4821481 and rs3752462 polymorphisms were genotyped. Outcome was defined as doubling of serum creatinine, or end stage renal disease (ESRD). RESULTS: The mean follow-up of patients was 6.1 years, with an initial mean creatinine of 1.6 g/dL and mean proteinuria 3.9 g/day. On enrollment nineteen patients were on dialysis and did not recover renal function, they were withdraw from analyses of progressive kidney disease. On follow up, from 177 remaining patients, 43 (24%) showed the composite outcome: dialysis, or doubling creatinine. Progressors had higher renal SLEDAI (10 vs 8.9, p = 0.04), higher chronicity index at biopsy (5 vs 2, p <0.001) and more frequently renal flares (82, 9% vs. 53.8%, p=0.002), as well as lower rates of complete or partial remission (p <0.0001). The four polymorphisms segregate as a haplotype, according the Hardy-Weinberg model. Analysing each polymorphism, only TT/CT genotype from rs3752462 polymorphism was associated with the outcome of DC/ESRD (p = 0.02). E1 haplotype were associated with progression with an OR of 1.79 (CI 1.02 to 3.0). DISCUSSION: The presence of the E1 haplotype is associated with worse prognosis of chronic renal failure in lupus nephritis patients
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Fatores genéticos associados ao clareamento espontâneo e resposta ao tratamento da infecção pelo vírus da hepatite C / Genetic factors associated with spontaneous clearance and response to treatment of hepatitis C infectionNastri, Ana Catharina de Seixas Santos 17 October 2016 (has links)
O vírus da hepatite C (HCV) é uma importante causa de doença hepática crônica e de complicações associadas, tais como cirrose e hepatocarcinoma (HCC). Fatores virais e do hospedeiro são conhecidos preditores da terapia antiviral. Fatores do hospedeiro preditores da resposta viral sustentada (RVS) foram descobertos por estudos de associação genômica ampla (GWAS), correspondendo a polimorfismos de nucleotídeo único (SNPs) nos genes IFNL3 e IFNL4 (rs8099917, rs12979860 e rs368234815). O objetivo do presente trabalho foi verificar as frequências genotípicas dos SNPs rs8099917, rs12979860 e rs368234815 e avaliar a associação entre estes SNPs e a evolução clínica e a resposta ao tratamento da infecção pelo HCV tendo em conta a ancestralidade genética da população estudada. Neste estudo, foi observada a associação dos três polimorfismos tanto com o desfecho clínico quanto com a resposta ao tratamento com interferon peguilado (PEG-IFN) e ribavirina (RBV). Os polimorfismos rs12979860 e rs368234815 foram associados com aumento da sensibilidade (respectivamente 97,7%, IC 95% 87,2-100, e 93,3%, IC 95% 81,3-98,3) e com um maior valor preditivo de uma resposta positiva ao tratamento. Na análise multivariada ajustada por sexo, idade e ancestralidade genética, o haplótipo G/T/?G foi relacionado com a não-resposta ao tratamento (OR = 21,09, IC 95% 5,33-83,51; p < 0,001) e com uma chance maior de desenvolver infecção crônica (OR = 5,46, IC 95% 2,06-14,46; p=0,001), quando comparado com haplótipo T/C/TT. Estes resultados podem ajudar a ajustar políticas de tratamento para a infecção por HCV em populações com tais características genéticas, assim como nos permitem conhecer o perfil genético da nossa população em relação a esses polimorfismos / Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and associated complications such as liver cirrhosis and hepatocellular carcinoma (HCC). Viral and host factors are known to be predictors for anti-viral therapy. Host factors predictors of sustained viral response (SVR) were discovered by Genome-Wide Association Studies (GWAS), including single nucleotide polymorphisms (SNPs) near or on genes IFNL3 and IFNL4 (rs8099917, rs12979860 and rs368234815). The aim of the present work was verify the genotype frequencies of SNPs rs8099917, rs12979860 and rs368234815, and evaluate the association between these SNPs and HCV infection outcome taking into account the genetic ancestry of the population. In this study, there was an association of the three polymorphisms with both clinical outcome and response to treatment with pegylated interferon (PEG-IFN) and ribavirin (RBV). The polymorphisms rs12979860 and rs368234815 showed increased sensitivity (97.7%, 95% CI 87.2-100, and 93.3%, 95% CI 81.3-98.3 respectively) and greater predictive value of a positive response to treatment. In multivariable analysis adjusted by gender, age and genetic ancestry, the haplotype G/T/?G was related to non-response to treatment (OR = 21.09, 95% CI 5.33-83.51; p < 0.001) and to a higher chance to develop chronic infection (OR = 5.46, 95% CI 2.06-14.46; p=0.001) when compared to haplotype T/C/TT. These findings may help to adjust our treatment policies for HCV infection in populations with such genetic characteristics, as well as allowing us to get to know the genetic profile of our population for these polymorphisms
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Análise de polimorfismos de nucleotídeo único na cistite intersticial / Single nucleotide polymorphism analysis in interstitial cystitisCassão, Valter Dell Acqua 08 December 2017 (has links)
IINTRODUÇÃO: A Cistite Intersticial (CI) ou Síndrome da Bexiga Dolorosa (SBD) é uma síndrome crônica caracterizada pela presença de dor ou desconforto vesical ou pélvico e sintomas miccionais como urgência e aumento da frequência miccional diurna e noturna, na ausência de outra afecção identificável que justifique esses sintomas. Não existe até o momento nenhum teste diagnóstico ou marcador que defina a CI. Desta forma seu diagnóstico é predominantemente clínico, baseado nos sinais e sintomas e dependente da exclusão de outras doenças urológicas. A dificuldade no diagnóstico e no tratamento dessas pacientes reflete o pouco que se sabe sobre sua fisiopatologia e sobre as alterações genéticas presentes na doença. A identificação de marcadores pode proporcionar um melhor entendimento e manejo desses aspectos da síndrome. Na tentativa de identificar marcadores genéticos que possam estar associados a CI, avaliamos a presença de alguns polimorfismos genéticos, os polimorfismos de nucleotídeo único (SNP), no DNA de pacientes com os critérios diagnósticos de CI e comparamos sua prevalência entre as pacientes e também com um grupo controle representativo da população geral. A correlação desses polimorfismos considerando a CI e a intensidade de dor nessas pacientes ainda não foi estudada na literatura. OBJETIVOS: Analisar a presença de polimorfismos (SNP) em amostras de sangue de pacientes com CI e correlacionar a presença dos polimorfismos com o quadro de dor crônica. MÉTODOS: Foram selecionadas 34 pacientes do sexo feminino com diagnóstico de CI de acordo com os critérios do NIDDK e 23 pacientes do grupo controle (mulheres saudáveis apenas com incontinência urinária de esforço). As pacientes com o diagnóstico de CI foram estratificadas em dois grupos de acordo com o grau dos sintomas de dor crônica. Foram selecionados 20 polimorfismos para análise: rs1800871, rs1800872, rs1800896, rs1800471, rs1800629, rs361525, rs1800497, rs6311, rs6277, rs6276, rs6313, rs2835859, rs11127292, rs2243248, rs6887695, rs3212227, rs1799971, rs12579350, rs3813034, rs6746030. A genotipagem foi realizada através da técnica de PCR em tempo real (q-PCR) e correlacionada com o diagnóstico de CI e com a intensidade dos sintomas álgicos. RESULTADOS: O alelo polimórfico (T) do SNP rs11127292 foi mais frequente nas pacientes com CI em relação ao grupo controle (p:0,01). O alelo polimórfico (T) do SNP rs6311 foi significativamente mais frequente nas pacientes com dor mais intensa (p:0,03). A frequência do alelo selvagem (A) do SNP rs1799971 foi maior em pacientes com dor leve a moderada (p:0,04). CONCLUSÕES: Foram identificadas algumas diferenças na frequência dos polimorfismos nas pacientes estudadas, o que sugere a existência de um papel relevante dos SNP associados tanto à CI quando na intensidade dos sintomas de dor crônica nestas pacientes / INTRODUCTION: Interstitial cystitis (IC) or painful bladder syndrome (PBS) is a chronic syndrome characterized by the presence of bladder/pelvic pain or discomfort and voiding symptoms such as urgency and increased urinary waking and night-time frequency in the absence of another identifiable cause to justify these symptoms. So far, there is no diagnostic test or marker to establish the presence of IC. Thus, the diagnosis is predominantly clinical, based on signs and symptoms and dependent on the exclusion of other urological diseases. The difficulty in the diagnosis and treatment of these patients reflects the little that is known about IC physiopathology and about the genetic background of the disease. The identification of new markers may provide a better understanding and management of the syndrome. As an attempt to identify genetic markers that may be associated with IC, we evaluated the presence of some genetic polymorphisms, single nucleotide polymorphisms (SNPs), in the DNA of patients with the diagnostic criteria of IC, and we compared their prevalence among IC patients and with a control group representative of the general population. The correlation of these polymorphisms considering IC and pain intensity in these patients has not been studied in the literature. OBJECTIVES: To assess the presence of polymorphisms (SNPs) in blood samples from IC patients and to correlate the presence of polymorphisms with chronic pain. METHODS: Thirty-four female patients with a diagnosis of IC according to the NIDDK criteria and 23 control subjects (healthy women with stress urinary incontinence) were selected. Patients with the diagnosis of IC were stratified into two groups according to the degree of symptoms of chronic pain. We selected 20 polymorphisms for analysis: rs1800871, rs1800876, rs1800471, rs1800629, rs361525, rs1800497, rs6311, rs6277, rs6276, rs6313, rs2835859, rs11127292, rs2243248, rs6887695, rs3212227, rs1799971, rs12579350, rs3813034, rs6746030. Genotyping was performed using the real-time PCR technique (q-PCR) and correlated with the diagnosis of IC and intensity of pain symptoms. RESULTS: The polymorphic allele (T) of the SNP rs11127292 occurred with more frequency in patients with IC compared to the control group (p= 0.01). The polymorphic allele (T) of SNP rs6311 occurred with more frequency in patients with severe pain (p= 0.03). The frequency of wild-type (A) SNP rs1799971 was higher in patients with mild to moderate pain (p= 0.04). CONCLUSION: The results indicated differences in polymorphism frequency in the patients studied, suggesting the existence of a relevant role of SNPs associated with both IC and intensity of chronic pain symptoms in these patients
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Développement de PCRs multiplexes pour le diagnostic : microarrays analytiques / Development of multiplex PCR for diagnosis : analytical microarraysCloux Boccoz, Stéphanie 11 December 2015 (has links)
Les travaux présentés dans cette thèse font suite à celle de Melle LE GOFF. Ils se concentrent sur la technologie HIFI brevetée et développée pendant ses travaux. Une première partie du travail présenté dans ce manuscrit concerne le test HIFI Blood 96™ et plus particulièrement les améliorations et les évolutions apportées au test afin d'en faire un véritable outil de génotypage, multiparamétrique et haut-débit pouvant être installé dans les banques de sang dans le but de constituer des inventaires de sang génotypé de façon étendue, participant ainsi à améliorer la sécurité transfusionnelle. Il permet de caractériser 96 échantillons sur 15 polymorphismes (divisés en deux panels) associés aux groupes sanguins en approximativement 4h30. Cette plateforme a fait l'objet d'une étude de validation à moyenne échelle sur 583 donneurs pour le panel 1 et 190 donneurs pour le panel 2. La deuxième partie des travaux décrit l'adaptation de la technologie HIFI appliquée au diagnostic des pathologies respiratoires, avec le développement d'une autre plateforme, ReSynPlex, en partenariat avec 3 équipes de recherche de Grenoble / The work reported in this thesis follows the one undertaken by Ms LE GOFF. It is focused on HIFI technology, which is patented and developed during her thesis. The first part of this work concerns the HIFI Blood 96™ test, and particularly the improvements and developments adduced to the test to make it a real diagnostic tool, multiparametric and high-throughput which can be implemented in blood banks in order to constitute negative antigen inventories, thus contributing to improve blood safety. It allows to characterize 96 samples on 15 polymorphisms (divided in two panels) associated to blood group systems in approximately 4.5 hours. A mesoscale validation study has been conducted on 583 samples for panel 1 and 190 samples for panel 2. The second part of this work describes the adaptation of HIFI technology applied to diagnosis of respiratory tract infections, with the development of another platform, ReSynPlex, in partnership with 3 research teams in Grenoble
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Fatty Acid Desaturase Activities in Metabolic Syndrome and Cardiovascular Disease : Special Reference to Stearoyl-CoA-Desaturase and Biomarkers of Dietary FatWarensjö, Eva January 2007 (has links)
<p>The development of the metabolic syndrome (MetS) and cardiovascular diseases have been suggested to be influenced more by the quality than the amount of dietary fat. The FA composition of serum lipids may be used as biomarkers of dietary fat quality. FAs can, however, also be endogenously synthesized by lipogenic enzymes such as elongases and desaturases. Three desaturases are important in humans: Stearoyl-CoA-desaturase (SCD), ∆6-desaturase (D6D) and ∆5-desaturase (D5D) and surrogate measures of desaturase activities can be estimated as product-to-precursor FA ratios.</p><p>In this thesis, we demonstrated that high SCD, D6D and low D5D estimated activities predicted MetS 20 years later, as well as cardiovascular and total mortality during a maximum of 33.7 years. The relation between D5D and MetS was independent of lifestyle and BMI, while the relation between SCD, D6D and MetS was confounded by BMI. Serum proportions of palmitic (16:0), palmitoleic (16:1) and dihomo-γ-linoleic acids were higher and the serum proportion of linoleic acid (LA) lower at baseline in those individuals who developed MetS. Further, LA was inversely related to mortality, while palmitic, palmitoleic and dihomo-γ-linoleic acids were directly associated with mortality. We also demonstrated that a diet rich in saturated fat “induced” a similar serum FA pattern (including estimated desaturase activities) that was associated with MetS, cardiovascular disease and mortality. We also propose that the SCD ratio [16:1/16:0] might be a novel and useful marker of dietary saturated fat, at least in Western high-fat diets. Finally, genetic variations in the human SCD1 gene were linked to obesity and insulin sensitivity, results that agree with data in SCD1 deficient mice.</p><p>This thesis suggests that dietary fat quality and endogenous desaturation may play a role in the development of metabolic and cardiovascular diseases and the results support current dietary guidelines.</p>
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Fatty Acid Desaturase Activities in Metabolic Syndrome and Cardiovascular Disease : Special Reference to Stearoyl-CoA-Desaturase and Biomarkers of Dietary FatWarensjö, Eva January 2007 (has links)
The development of the metabolic syndrome (MetS) and cardiovascular diseases have been suggested to be influenced more by the quality than the amount of dietary fat. The FA composition of serum lipids may be used as biomarkers of dietary fat quality. FAs can, however, also be endogenously synthesized by lipogenic enzymes such as elongases and desaturases. Three desaturases are important in humans: Stearoyl-CoA-desaturase (SCD), ∆6-desaturase (D6D) and ∆5-desaturase (D5D) and surrogate measures of desaturase activities can be estimated as product-to-precursor FA ratios. In this thesis, we demonstrated that high SCD, D6D and low D5D estimated activities predicted MetS 20 years later, as well as cardiovascular and total mortality during a maximum of 33.7 years. The relation between D5D and MetS was independent of lifestyle and BMI, while the relation between SCD, D6D and MetS was confounded by BMI. Serum proportions of palmitic (16:0), palmitoleic (16:1) and dihomo-γ-linoleic acids were higher and the serum proportion of linoleic acid (LA) lower at baseline in those individuals who developed MetS. Further, LA was inversely related to mortality, while palmitic, palmitoleic and dihomo-γ-linoleic acids were directly associated with mortality. We also demonstrated that a diet rich in saturated fat “induced” a similar serum FA pattern (including estimated desaturase activities) that was associated with MetS, cardiovascular disease and mortality. We also propose that the SCD ratio [16:1/16:0] might be a novel and useful marker of dietary saturated fat, at least in Western high-fat diets. Finally, genetic variations in the human SCD1 gene were linked to obesity and insulin sensitivity, results that agree with data in SCD1 deficient mice. This thesis suggests that dietary fat quality and endogenous desaturation may play a role in the development of metabolic and cardiovascular diseases and the results support current dietary guidelines.
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