982 resultados para Cyp1a1 Polymorphisms
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Formaldehyde (FA) is a colourless gas widely used in the industry and hospitals as an aqueous solution, formalin. It is extremely reactive and induces various genotoxic effects in proliferating cultured mammalian cells. Tobacco smoke has been epidemiologically associated to a higher risk of development of cancer, especially in the oral cavity, larynx and lungs, as these are places of direct contact with many carcinogenic tobacco’s compounds. Genetic polymorphisms in enzymes involved in the metabolism are very important and can make changes in the individual susceptibility to disease. Alcohol dehydrogenase class 3 (ADH3), also known as formaldehyde dehydrogenase dependent of glutathione, is the major enzyme involved in the formaldehyde oxidation, especially in the buccal mucosa. The polymorphism in study is a substitution of an isoleucine for a valine in codon 349. The cytokinesis-blocked micronucleus assay (CBMN) in human lymphocytes is one of the most commonly used methods for measuring DNA damage, namely the detection of micronucleus, nucleoplasmic bridges, and nuclear buds, classified as genotoxicity biomarkers.
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A Diabetes mellitus tipo 2 (DM2) é uma patologia de etiologia múltipla à qual estão associados vários factores genéticos. A Enzima Conversora da Angiotensina (ECA) tem sido alvo de vários estudos pela sua relação com factores pró-inflamatórios, pró-oxidantes e pró-fibrose, sendo o polimorfismo de Inserção/Delecção o mais estudado. Neste contexto, o objectivo deste estudo é assim verificar a distribuição deste polimorfismo numa amostra de indivíduos de nacionalidade portuguesa e verificar a sua possível associação com a DM2. Para tal, foram analisadas 87 amostras (controlos n =24 e diabéticos n =63) de indivíduos de nacionalidade portuguesa. As amostras foram submetidas a um processo de extracção de ADN, sendo posteriormente amplificadas por Polymerase Chain Reaction e analisadas por eletroforese em gel de agarose a 1%. Observou-se uma prevalência de 8% (n=7) com genótipo I/I, 38% (n=33) com genótipo I/D e 54% (n=47) com genótipo D/D. A amostra em estudo demonstrou assim estar sob o equilíbrio Hardy-Weinberg. Observou-se também uma associação entre níveis mais elevados de glicemia e o genótipo I/I (p=0,019). Na análise da utilização de insulina no controlo dos níveis de glicemia na DM2, observou-se uma maior proporção de indivíduos com genótipo D/D. Este estudo demonstra a importância do investimento da caracterização genética em patologias metabólicas multifactoriais como a DM2.
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As sequelas fisiopatológicas do stress oxidativo são difíceis de quantificar. Apesar dos obstáculos, a relevância médica do stress oxidativo tem vindo a ser cada vez mais reconhecida, sendo hoje em dia encarado como um componente chave de virtualmente todas as doenças. A disfunção erétil (DE) surge neste contexto como uma espécie de barómetro da função endotelial e do dano oxidativo. A quantificação de biomarcadores de stress oxidativo poderá apresentar um enorme impacto na avaliação de pacientes com DE. O rácio glutationa reduzida/oxidada (GSH/GSSG) e a nitrotirosina (3-NT) têm vindo a demonstrar relevância clínica. A consideração de polimorfismos genéticos constitui ainda uma abordagem promissora na avaliação destas relações no futuro. Um método altamente sensível de cromatografia líquida de alta performance (HPLC) foi desenvolvido para a determinação de 3-NT em plasma humano. As concentrações de 3-NT medidos em indivíduos com DE foram 6,6±2,1μM (média±S.D., n = 46). A medição da concentração plasmática de 3-NT poderá revelar-se útil como marcador de dano oxidativo dependente do óxido nítrico (NO). O nível de stress oxidativo pode também ser quantificado através da medição do decréscimo do rácio GSH/GSSG, que tem mostrado alterações numa miríade de patologias, como a DE e a diabetes mellitus. O método proposto para a quantificação do rácio GSH/GSSG em HPLC apresenta a vantagem de avaliação concomitante dos dois parâmetros em apenas uma corrida. O valor do rácio GSH/GSSG obtido a partir de sangue de indivíduos com DE foi 11,9±9,8 (média±S.D., n = 49). Os resultados estatísticos revelaram diferenças significativas (p<0,001) entre ambos a concentração plasmática de 3-NT e o rácio GSH/GSSG de sangue de indivíduos com DE e as respetivas medições em indivíduos saudáveis. Observaram-se ainda diferenças estatisticamente significativas (p≈0,027) entre o rácio GSH/GSSG do sangue de pacientes apenas com diagnóstico de DE e a medição respetiva em indivíduos com DE e comorbilidades cardiovasculares. Estes resultados enfatizam o papel do dano oxidativo na biopatologia da DE, elucidado com o auxílio destas duas metodologias, que poderão ter um amplo campo de aplicação no futuro, dado que se mostraram simples, não dispendiosas e rápidas, podendo eventualmente adequar-se a estudos de rastreio em larga escala.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Objective Deregulation of FAS/FASL system may lead to immune escape and influence bacillus Calmette-Guérin (BCG) immunotherapy outcome, which is currently the gold standard adjuvant treatment for high-risk non–muscle invasive bladder tumors. Among other events, functional promoter polymorphisms of FAS and FASL genes may alter their transcriptional activity. Therefore, we aim to evaluate the role of FAS and FASL polymorphisms in the context of BCG therapy, envisaging the validation of these biomarkers to predict response. Patients and methods DNA extracted from peripheral blood from 125 patients with bladder cancer treated with BCG therapy was analyzed by Polymerase Chain Reaction—Restriction Fragment Length Polymorphism for FAS-670 A/G and FASL-844 T/C polymorphisms. FASL mRNA expression was analyzed by real-time Polymerase Chain Reaction. Results Carriers of FASL-844 CC genotype present a decreased recurrence-free survival after BCG treatment when compared with FASL-844 T allele carriers (mean 71.5 vs. 97.8 months, P = 0.030) and have an increased risk of BCG treatment failure (Hazard Ratio = 1.922; 95% Confidence Interval: [1.064–3.471]; P = 0.030). Multivariate analysis shows that FASL-844 T/C and therapeutics scheme are independent predictive markers of recurrence after treatment. The evaluation of FASL gene mRNA levels demonstrated that patients carrying FASL-844 CC genotype had higher FASL expression in bladder tumors (P = 0.0027). Higher FASL levels were also associated with an increased risk of recurrence after BCG treatment (Hazard Ratio = 2.833; 95% Confidence Interval: [1.012–7.929]; P = 0.047). FAS-670 A/G polymorphism analysis did not reveal any association with BCG therapy outcome. Conclusions Our results suggest that analysis of FASL-844 T/C, but not FAS-670 A/G polymorphisms, may be used as a predictive marker of response to BCG immunotherapy.
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Background: The aim was to evaluate the presence of metabolic bone disease (MBD) in patients with Crohn’s disease (CD) and to identify potential etiologic factors. Methods: The case–control study included 99 patients with CD and 56 controls with a similar age and gender distribution. Both groups had dual-energy x-ray absorptionmetry and a nutritional evaluation. Single nucleotide polymorphisms at the IL1, TNF-a, LTa, and IL-6 genes were analyzed in patients only. Statistical analysis was performed using SPSS software. Results: The prevalence of MBD was significantly higher in patients (P ¼ 0.006). CD patients with osteoporosis were older (P < 0.005), small bowel involvement and surgical resections were more frequent (P < 0.005), they more often exhibited a penetrating or stricturing phenotype (P < 0.05), duration of disease over 15 years (P < 0.005), and body mass index (BMI) under 18.5 kg/m2 (P < 0.01) were more often found. No association was found with steroid use. Patients with a Z-score < 2.0 more frequently had chronic active disease (P < 0.05). With regard to diet, low vitamin K intake was more frequent (P ¼ 0.03) and intake of total, monounsaturated, and polyunsaturated fat was higher in patients with Z-score < 2.0 (P < 0.05). With respect to genetics, carriage of the polymorphic allele for LTa252 A/G was associated with a higher risk of osteoporosis (P ¼ 0.02). Regression analysis showed that age over 40 years, chronic active disease, and previous colonic resections were independently associated with the risk of developing MBD. Conclusions: The prevalence of MBD was significantly higher in CD patients. Besides the usual risk factors, we observed that factors related to chronic active and long-lasting disease increased the risk of MBD.
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Background: Polymorphisms located in genes involved in the metabolism of folate and some methyl-related nutrients are implicated in colorectal cancer (CRC). Objective: We evaluated the association of 3 genetic polymorphisms [C677T MTHFR (methylene tetrahydrofolate reductase), A2756G MTR (methionine synthase), and C1420T SHMT (serine hydroxymethyltransferase)] with the intake of methyl-donor nutrients in CRC risk. Design: Patients withCRC(n 196) and healthy controls (n 200) matched for age and sex were evaluated for intake of methyl-donor nutrients and the 3 polymorphisms. Results: Except for folate intake, which was significantly lower in patients (P 0.02), no differences were observed in the dietary intake of other methyl-donor nutrients between groups. High intake of folate ( 406.7 g/d) was associated with a significantly lower risk of CRC (odds ratio: 0.67; 95% CI: 0.45, 0.99). The A2756G MTR polymorphism was not associated with the risk of developing CRC. In contrast, homozygosity for the C677TMTHFRvariant (TT) presented a 3.0-fold increased risk of CRC (95% CI: 1.3, 6.7). Similarly, homozygosity for the C1420T SHMT polymorphism also had a 2.6-fold increased risk (95% CI: 1.1, 5.9) of developing CRC. When interactions between variables were studied, low intake of all methyl-donor nutrients was associated with an increased risk ofCRC in homozygous participants for the C677T MTHFR polymorphism, but a statistically significant interaction was only observed for folate (odds ratio: 14.0; 95% CI: 1.8, 108.5). No significant associations were seen for MTR or SHMT polymorphisms. Conclusion: These results show an association between the C677T MTHFR variant and different folate intakes on risk of CRC.
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Introduction - Obesity became a major public health problem as a result of its increasing prevalence worldwide. Paraoxonase-1 (PON1) is an esterase able to protect membranes and lipoproteins from oxidative modifications. At the PON1 gene, several polymorphisms in the promoter and coding regions have been identified. The aims of this study were i) to assess PON1 L55M and Q192R polymorphisms as a risk factor for obesity in women; ii) to compare PON1 activity according to the expression of each allele in L55M and Q192R polymorphisms; iii) to compare PON1 activity between obese and normal-weight women. Materials and methods - We studied 75 healthy (35.9±8.2 years) and 81 obese women (34.3±8.2 years). Inclusion criteria for obese subjects were body mass index ≥30 kg/m2 and absence of inflammatory/neoplasic conditions or kidney/hepatic dysfunction. The two PON1 polymorphisms were assessed by real-time PCR with TaqMan probes. PON1 enzymatic activity was assessed by spectrophotometric methods, using paraoxon as a substrate. Results - No significant differences were found for PON1 activity between normal and obese women. Nevertheless, PON1 activity was greater (P<0.01) for the RR genotype (in Q192R polymorphism) and for the LL genotype (in L55M polymorphism). The frequency of allele R of Q192R polymorphism was significantly higher in obese women (P<0.05) and was associated with an increased risk of obesity (odds ratio=2.0 – 95% confidence interval (1.04; 3.87)). Conclusion - 55M and Q192R polymorphisms influence PON1 activity. The allele R of the Q192R polymorphism is associated with an increased risk for development of obesity among Portuguese Caucasian premenopausal women.
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Aim - To identify clinical and/or genetic predictors of response to several therapies in Crohn’s disease (CD) patients. Methods - We included 242 patients with CD (133 females) aged (mean ± standard deviation) 39 ± 12 years and a disease duration of 12 ± 8 years. The single-nucleotide polymorphisms (SNPs) studied were ABCB1 C3435T and G2677T/A, IL23R G1142A, C2370A, and G9T, CASP9 C93T, Fas G670A and LgC844T, and ATG16L1 A898G. Genotyping was performed with real-time PCR with Taqman probes. Results - Older patients responded better to 5-aminosalicylic acid (5-ASA) and to azathioprine (OR 1.07, p = 0.003 and OR 1.03, p = 0.01, respectively) while younger ones responded better to biologicals (OR 0.95, p = 0.06). Previous surgery negatively influenced response to 5-ASA compounds (OR 0.25, p = 0.05), but favoured response to azathioprine (OR 2.1, p = 0.04). In respect to genetic predictors, we observed that heterozygotes for ATGL16L1 SNP had a significantly higher chance of responding to corticosteroids (OR 2.51, p = 0.04), while homozygotes for Casp9 C93T SNP had a lower chance of responding both to corticosteroids and to azathioprine (OR 0.23, p = 0.03 and OR 0.08, p = 0.02,). TT carriers of ABCB1 C3435T SNP had a higher chance of responding to azathioprine (OR 2.38, p = 0.01), while carriers of ABCB1 G2677T/A SNP, as well as responding better to azathioprine (OR 1.89, p = 0.07), had a lower chance of responding to biologicals (OR 0.31, p = 0.07), which became significant after adjusting for gender (OR 0.75, p = 0.005). Conclusions - In the present study, we were able to identify a number of clinical and genetic predictors of response to several therapies which may become of potential utility in clinical practice. These are preliminary results that need to be replicated in future pharmacogenomic studies.
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Applied and Environmental Microbiology, Vol. 73, No.4
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A diabetes mellitus do tipo 1 (DM1) é o distúrbio endócrino-metabólico mais frequente em crianças. É uma doença autoimune resultado da destruição selectiva das células beta pancreáticas. A velocidade de destruição das células beta pode ser rápida em algumas pessoas e lenta em outras; esta última é típica de adulto é conhecido como diabetes autoimune latente em adulto (LADA). A sua etiologia envolve factores ambientais e genéticos, dos genes envolvidos a maior contribuição vem da região do genoma onde estão localizados os genes do Complexo Principal de Histocompatibilidade (MHC). A combinação de diferentes alelos do sistema de antigénio leucocitário humano tipo II (HLAII) esta associada a susceptibilidade da doença e as principais molécula envolvidas são a DQ e DR. O estágio pré-clínico da doença se caracteriza pela presença de auto-anticorpos, sendo o anti-GAD o mais sensível nesta patologia. OBJECTIVO: Analizar a frequência dos polimorfismos HLA-DR/DQ em angolanos portadores de diabetes tipo 1, residentes em Luanda. O tipo de estudo adotado foi casocontrolo num universo de voluntários provenientes da consulta externa de hospitais e clínicas locais no período de outubro de 2012 a outubro 2013. A amostra biológica utilizada foi sangue total, tendo sido processada no laboratório LABGENE, da Faculdade de Medicina (FM) da Universidade Agostinho Neto (UNA). Os auto-anticorpos, anti-GAD, foram doseados pelo método de ELISA. O ADN genómico foi extraído à partir de sangue total periférico e tipagem genética foi realizada mediante PCR-SSP.O alelo DQB1*02 (DQ2/DQ2) (p=0,033, OR= 4, IC (1,2-13,3) foi associado a susceptibilidade da DM1; os alelos DQB1*06 (DQ6/DQ6) (p=0,000, OR=0,30, IC (0,17-0,54); *11 (p=0,011, OR=0,14, IC=0,032-0,62); *13 (p=0,006, OR=0,13, IC=0,049-0,588) e *15 (p=0,001, OR=0,044, IC=0,005-0,39) foram associados a proteção. Foi encontrado 29,2% de positividade para o anti-GAD, não houve associação significativa (p=0,69) entre a resposta positiva do anti-GAD e a idade. Não foi encontrada associação significativa (p=0,39) entre o tempo de diagnóstico e resposta humoral. Observou-se associação significativa entre os alelos de risco DQB1*02 (p=0.000) e resposta positiva para anti-GAD; da mesma maneira houve uma associação significativa para os alelos DQB1*06 (p=0,002), DRB1*11 (p=0,048); *13 (p=0,004) e *15 (p=0,021) e a resposta negativa do anti-GAD.Os dados demostram o forte envolvimentos do gene HLA-II (DQ) com a suceptibilidade a DM1 e sugere que a autoimunidade se desenvolve na presença de susceptibilidade genética, quer dizer, em associação com alelos HLA-II específicos.
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RESUMO: O cancro da mama é a patologia oncológica mais frequente nas mulheres sendo o responsável pela maior taxa de mortalidade por cancro no sexo feminino. Contudo, as causas inerentes a esta patologia permanecem por esclarecer. Nos últimos anos tem-se verificado que o risco para patologia neoplásica depende de factores ambientais e genéticos, estando estes últimos associados à variabilidade genética inter-individual. Polimorfismos genéticos em genes envolvidos no metabolismo de hormonas sexuais, de cancerígenos ambientais e na reparação da lesão genética, são potenciais candidatos a estarem associados à susceptibilidade individual para esta patologia. Assim, neste trabalho desenvolveram-se estudos de associação caso-controlo na população Portuguesa, com vista a avaliar-se o papel atribuído aos polimorfismos na susceptibilidade para cancro da mama. Foram seleccionados polimorfismos em genes envolvidos em diferentes vias mecanicistas: destoxificação de cancerígenos, metabolismo de estrogénios, reparação por excisão de bases, reparação por excisão de nucleótidos, reparação mismatch e reparação por recombinação homóloga. Os resultados obtidos revelaram associação entre os seguintes polimorfismos e a susceptibilidade individual para cancro da mama: os dois SNPs estudados no gene XRCC1 (Arg194Trp e Arg399Gln) e o SNP no gene XRCC3 (Thr241Met) após estratificação pelo status menopausico. Mediante estratificação por status de amamentação os SNPs identificados nos genes MnSOD (Val16Ala) e XRCC2 (Arg118His); um SNP no gene MLH3 (Leu844Pro), e por fim como resultado de interacção gene-gene as interacções descritas por MSH3 Ala1045Thr/MSH6 Gly39Glu e MSH4 Ala97Thr/MLH3 Leu844Pro. Os resultados obtidos e apresentados na presente dissertação, revelam que o estudo de polimorfismos pode representar um papel determinante na etiologia do cancro da mama. No entanto, mais estudos envolvendo estes mesmos polimorfismos em populações casuisticamente superiores serão uma mais-valia nos estudos de associação para esta neoplasia. Adicionalmente, a utilização da metodologia de Pools de DNA, poderá ser uma ferramenta útil na pré-selecção dos polimorfismos mais relevantes a estudar, na medida em que permite estimar a frequência alélica de cada SNP numa determinada população.-----------------------------------ABSTRACT: Breast cancer is the most common form of cancer among women, being the responsible for the highest mortality rate from cancer among the female sex. However, the main causes related to this pathology remain unclear. The risk of neoplasic disease has been connected with genetic and environmental factors. In fact, genes and the environment share the stage for most, if not all, common non-familial cancers, and are related to individual susceptibility. Genetic polymorphisms identified in genes encoding enzymes involved in estrogen metabolism, xenobiotics and DNA repair pathways are believed to be candidates for associations with breast cancer. Therefore, it was our intention to develop case-control studies among the Portuguese population, in order to evaluate the potential role of several genetic polymorphisms in breast cancer susceptibility. We selected polymorphisms in genes involved in different pathways: carcinogenic detoxification, estrogen metabolism, base excision repair, nucleotide excision repair, mismatch repair and double strand break repair by homologous recombination. The results obtained revealed potential associations between some polymorphisms studied and individual susceptibility to breast cancer. Regarding this fact, our results suggest the potential involvement of two XRCC1 gene polymorphisms (Arg194Trp and Arg399Gln) and XRCC3 gene polymorphism (Thr241Met) after stratification to menopausal status and after stratification to breastfeeding status an association of MnSOD gene polymorphism (Val16Ala) and XRCC2 (Arg188His) with the disease. The SNP identified in MLH3 gene (Leu844Pro), and the interaction gene-gene described by MSH3 Ala1045Thr/MSH6 Gly39Glu and MSH4 Ala97Thr/MLH3 Leu844Pro were also related to breast cancer susceptibility. The results shown in the present dissertation have revealed the potential role of polymorphisms in breast cancer etiology. However, further studies will be needed with larger populations to confirm these results. Additionally, the use of DNA pools methodology, as a pre-selection tool, could allow the identification of the most relevant polymorphisms to be studied, estimating the allelic frequency of each SNPs in different populations.
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The most effective therapeutic option for managing nonmuscle invasive bladder cancer (NMIBC), over the last 30 years, consists of intravesical instillations with the attenuated strain Bacillus Calmette-Gu´erin (the BCG vaccine). This has been performed as an adjuvant therapeutic to transurethral resection of bladder tumour (TURBT) and mostly directed towards patients with highgrade tumours, T1 tumours, and in situ carcinomas. However, from 20% to 40% of the patients do not respond and frequently present tumour progression. Since BCG effectiveness is unpredictable, it is important to find consistent biomarkers that can aid either in the prediction of the outcome and/or side effects development. Accordingly, we conducted a systematic critical review to identify themost preeminent predictive molecular markers associated with BCG response. To the best of our knowledge, this is the first review exclusively focusing on predictive biomarkers for BCG treatment outcome. Using a specific query, 1324 abstracts were gathered, then inclusion/exclusion criteria were applied, and finally 87 manuscripts were included. Several molecules, including CD68 and genetic polymorphisms, have been identified as promising surrogate biomarkers. Combinatory analysis of the candidate predictive markers is a crucial step to create a predictive profile of treatment response.
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RESUMO: O aborto recorrente (AR) é um evento extremamente traumático com grande impacto na vida dos casais. Apesar de avanços significativos verificados na investigação médica, cerca de 50% dos casos continua sem uma causa identificada. Alguns aspectos como a caracterização inadequada das doentes e das perdas gestacionais, assim como diferentes metodologias utilizadas no seu estudo, têm influenciado a prevalência de alguns dos factores causais e dificultado a compreensão do AR. Da mesma forma, pouco se sabe sobre as diferenças de género na vivência psicológica do aborto recorrente e das suas eventuais repercussões para o relacionamento do casal, centrando-se os poucos estudos existentes preferencialmente na mulher. Por esta razão, o objectivo desta tese foi a caracterização dos factores médicos associados ao AR e das consequências psicológicas desta entidade, contribuindo para promover estratégias clínicas baseadas na evidência específica. Na primeira parte desta tese (capítulos 1 e 2), após uma breve introdução geral e através de uma revisão da literatura, efectua-se uma reflexão sobre o tema, abordando a epidemiologia do aborto recorrente, os factores médicos e os aspectos psicológicos associados. Nos capítulos 3 e 4 descrevemos três estudos efectuados em mulheres portuguesas com aborto recorrente. O primeiro estudo teve por objectivo caracterizar os factores médicos e determinar o padrão da perda recorrente de gravidez, numa coorte de mulheres submetidas a um protocolo de diagnóstico definido. As participantes foram agrupadas de acordo com a paridade (AR primário ou secundário) e a idade gestacional das perdas (embrionárias ou fetais). As anomalias da cavidade uterina, a SAAF e as translocações equilibradas parentais foram os factores mais prevalentes. 15,6% das participantes eram obesas. Em 55,5% dos casos não foi identificado nenhum factor. A história obstétrica materna influenciou significativamente os resultados encontrados: os factores anatómicos e a SAAF foram mais prevalentes em nulíparas e as perdas inexplicadas foram mais frequentes em mulheres com AR secundário. Assim, os nossos dados reforçam os resultados de pesquisas anteriores sobre a importância da obesidade, da síndrome de anticorpos antifosfolípidos e das anomalias uterinas estruturais como factores associados ao AR e mostram que os a paridade é um moderador da importância desses factores. Capítulo 6 94 A ausência de resultados consensuais na literatura sobre a etiologia do AR condiciona a pesquisa sistemática de alguns factores, envolvendo exames dispendiosos, muitas vezes sem que exista evidência que suporte a sua associação com esta entidade. A trombofilia hereditária é uma das condições frequentemente investigadas nestas doentes. O nosso segundo estudo pretende contribuir para clarificar o papel de duas mutações (factor V Leiden e protrombina G20210A) na perda recorrente de gravidez e esclarecer a necessidade do seu rastreio nestas situações. Foi efectuada a pesquisa destes polimorfismos em 100 mulheres com AR inexplicado e num grupo de controlo de multíparas sem história de perdas de gravidez. Na nossa amostra não se verificou uma associação entre perdas embrionárias recorrentes e estas mutações. Nas mulheres com este tipo de perdas, a prevalência do FLV foi inclusive menor do que a verificada nos controlos. Pelo contrário, nas participantes com perdas fetais a prevalência destes polimorfismos foi muito superior à verificada nos controlos, sugerindo uma possível associação entre estas duas entidades. A pequena dimensão deste último subgrupo de mulheres, não nos permitiu contudo tirar conclusões. Uma investigação prospectiva multicêntrica é necessária antes de recomendar a pesquisa da trombofilia hereditária na investigação do AR. Procurámos incluir também nesta tese uma dimensão psicológica e contribuir assim para o conhecimento dos processos relacionais originados pelo AR. No terceiro estudo foram investigadas as diferenças de género na vivência do AR e o seu impacto no relacionamento e sexualidade do casal. Participaram neste estudo 30 casais sem filhos, com pelo menos 3 abortos espontâneos consecutivos. Cada membro do casal respondeu a um conjunto de questionários (Impact of Events Scale, Perinatal Grief Scale, Partnership Questionnaire e Intimate Relationship Scale). Os resultados mostram que as mulheres sofrem mais intensamente do que os homens com o AR, relacionando-se a intensidade do seu sofrimento com a qualidade do relacionamento conjugal. A sexualidade do casal é também afectada pelo stress e pelo sofrimento associados ao AR. Uma avaliação e acompanhamento deste tipo de problemas são imprescindíveis para ajudar estes casais a manterem a qualidade afectiva e sexual da sua relação. Finalmente, no capítulo 5 sumariámos as conclusões de toda a contribuição pessoal para a investigação sobre os factores associados e repercussões para o casal da perda recorrente de gravidez.-------------------ABSTRACT: Recurrent miscarriage (RM), a rare condition, has been described as a traumatic event for couples. Parental chromosomal anomalies, maternal thrombophilic disorders and structural uterine anomalies have been directly associated with RM. However, despite significant advances in medical research, the vast majority of cases remain unexplained. Aspects as the ethnic diversity of the population with different expression of genes, the inappropriate characterization of patients and of pregnancy losses, as well as different methodologies used in their study, have influenced the prevalence of etiological factors and have hampered the understanding of this problem. Similarly, little is known about gender differences in psychological experience of RM and its implications for the relationship of the couple. The first objective of this thesis is the characterization of the medical factors and of the psychological consequences related with RM, in the Portuguese population, helping to promote specific evidence-based clinical strategies. In the first part of this thesis, and after a brief general introduction (Chapter 1), a critical review of literature on the definition, the epidemiology and the dimensions involved, with a special emphasis on associated medical and psychological aspects of recurrent miscarriage, is presented (Chapter 2). In Chapters 3 and 4 we describe three studies carried out in Portuguese couples with RM. The first study aimed to investigate the etiological factors and the pattern of pregnancy loss in a cohort of women with RM. Subjects were divided in groups according to their parity (primary or secondary RM) and time of pregnancy loss (embryonic or fetal). Parental chromosome anomalies, uterine anomalies and antiphospholipid syndrome were the most prevalent medical factors. 15.6% of the women were obese. In the majority of cases (55.5%) no identifiable cause was detected. Parity influenced significantly our results. There was a higher prevalence of anatomic factors and antiphospholipid syndrome in primary RM. On the other hand, unexplained losses were more frequent in secondary RM. Except for the parental chromosomal abnormalities; the frequency of risk factors was similar among women with fetal or embryonic losses. Our data emphasizes the results of previous research on the importance of obesity, antiphospholipid syndrome and structural uterine abnormalities as known risk factors for RM, and shows that parity is an important moderator of the weight of those risk factors. Our second study aims to clarify the role of two mutations (factor V Leiden and prothrombin G20210A) and elucidate the need for their screening in Portuguese women with RM. FVL and PT G20210A analysis was carried out in 100 women with three or more consecutive miscarriages and a control group of 100 parous controls with no history of pregnancy losses. Secondary analysis was made regarding gestational age at miscarriage (embryonic and fetal loss). Overall the prevalence of FVL and PT G20210A was similar in RM women compared with controls. In the RM embryonic subgroup of women, FVL prevalence was inclusively lower than that of controls. Conversely in women with fetal losses both polymorphisms were much more frequent, although statistical significance was not reached due to the small size of this subgroup of patients. These data indicate that inherited maternal thrombophilia is not associated with RM prior to 10 weeks of gestation. Therefore, its screening is not indicated as an initial approach in Portuguese women with RM and a negative personal history of thromboembolic.96 Our second study aims to clarify the role of two mutations (factor V Leiden and prothrombin G20210A) and elucidate the need for their screening in Portuguese women with RM. FVL and PT G20210A analysis was carried out in 100 women with three or more consecutive miscarriages and a control group of 100 parous controls with no history of pregnancy losses. Secondary analysis was made regarding gestational age at miscarriage (embryonic and fetal loss). Overall the prevalence of FVL and PT G20210A was similar in RM women compared with controls. In the RM embryonic subgroup of women, FVL prevalence was inclusively lower than that of controls. Conversely in women with fetal losses both polymorphisms were much more frequent, although statistical significance was not reached due to the small size of this subgroup of patients. These data indicate that inherited maternal thrombophilia is not associated with RM prior to 10 weeks of gestation. Therefore, its screening is not indicated as an initial approach in Portuguese women with RM and a negative personal history of thromboembolic. In our third study, we investigate gender differences in RM experience and its impact on the couple's relationship and sexuality. Each member of 30 couples with RM answered a set of questionnaires, including the Impact of Events Scale (Horowitz et al., 1979), the Perinatal Grief Scale (Toedter et al., 1988), the Partnership Questionnaire (Hahlweg, 1979) and the Intimate Relationship Scale (Hetherington e Soeken, 1990). Results showed that men do grieve, but less intensely than women. Although the quality of the couple‟s relationship seemed not to be adversely affected by RM, both partners described sexual changes after those events. Grief was related to the quality of communication in the couple for women, and to the quality of sex life for men. An understanding of such issues is critical in helping these couples to maintain sexual and affective quality of their relationship. Finally, in Chapter 5, conclusions and clinical implications of all personal contribution to the investigation on associated factors and relational consequences of recurrent miscarriage are presented.
Resumo:
Background Hippocampal neurogenesis has been suggested as a downstream event of antidepressants (AD) mechanism of action and might explain the lag time between AD administration and the therapeutic effect. Despite the widespread use of AD in the context of Major Depressive Disorder (MDD) there are no reliable biomarkers of treatment response phenotypes, and a significant proportion of patients display Treatment Resistant Depression (TRD). Fas/FasL system is one of the best-known death-receptor mediated cell signaling systems and is recognized to regulate cell proliferation and tumor cell growth. Recently this pathway has been described to be involved in neurogenesis and neuroplasticity. Methods Since FAS -670A>G and FASL -844T>C functional polymorphisms never been evaluated in the context of depression and antidepressant therapy, we genotyped FAS -670A>G and FASL -844T>C in a subset of 80 MDD patients to evaluate their role in antidepressant treatment response phenotypes. Results We found that the presence of FAS -670G allele was associated with antidepressant bad prognosis (relapse or TRD: OR=6.200; 95% CI: [1.875–20.499]; p=0.001), and we observed that patients carrying this allele have a higher risk to develop TRD (OR=10.895; 95% CI: [1.362–87.135]; p=0.008).Moreover, multivariate analysis adjusted to potentials confounders showed that patients carrying G allele have higher risk of early relapse (HR=3.827; 95% CI: [1.072–13.659]; p=0.039). FAS mRNA levels were down-regulated among G carriers, whose genotypes were more common in TRD patients. No association was found between FASL-844T>C genetic polymorphism and any treatment phenotypes. Limitations Small sample size. Patients used antidepressants with different mechanisms of action. Conclusion To the best of our knowledge this is the first study to evaluate the role of FAS functional polymorphism in the outcome of antidepressant therapy. This preliminary report associates FAS -670A>G genetic polymorphism with Treatment Resistant Depression and with time to relapse. The current results may possibly be given to the recent recognized role of Fas in neurogenesis and/or neuroplasticity.