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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.
311

Análise de preditores clínicos e genéticos para o surgimento de discinesias induzidas por L-DOPA na doença de Parkinson / Analysis of clinical and genetic predictors for the onset of L-DOPA-induced dyskinesias in Parkinson\'s disease

Santos, Bruno Lopes dos 29 August 2017 (has links)
A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais comum do mundo, e seu tratamento atual se baseia principalmente no uso de medicações que facilitam a transmissão dopaminérgica nos núcleos da base. A L-DOPA é a principal medicação usada no tratamento da DP, contudo seu uso crônico está associado ao surgimento de complicações motoras, como as discinesias induzidas por L-DOPA (DIL). As DIL ocorrem em cerca de 50% dos pacientes com DP que usaram LDOPA por cerca de 4 a 6 anos, e podem causar uma série de impactos negativos aos pacientes. Pela incapacidade adicional que esta complicação traz aos pacientes com DP, a definição de fatores que possam predizer o surgimento das DIL é de importância direta para o clínico que prescreve L-DOPA rotineiramente. O objetivo deste estudo foi determinar os principais fatores de risco clínicos e genéticos para o desenvolvimento de DIL em uma casuística de pacientes brasileiros com DP. Um estudo transversal foi realizado em pacientes brasileiros de dois centros (Ribeirão Preto e São Paulo) como parte do projeto \"Latin American Research Consortium on the Genetics of PD\" (LARGE-PD), incluindo apenas pacientes com DP e em uso de L-DOPA. A avaliação foi baseada em um exame neurológico completo e em uma entrevista semi-estruturada feita por um médico neurologista especialista em Distúrbios de Movimentos. A presença de DIL foi considerada se a pontuação fosse >= 1 no item 32 da Parte IV na MDS-UPDRS. Baseados em estudos prévios, nós escolhemos oito polimorfismos tipo single nucleotide polymorphism (SNP) nestes genes: COMT, MAOB, ANKK1, DRD3, DAT1, BDNF, ADORA2A and NOS1. A genotipagem foi realizada através de ensaios TaqMan SNP. Foram realizados modelos de regressão logística e análises de sobrevivência para identificarmos os fatores de risco clínicos e genéticos associados ao surgimento de DIL. Ao todo, foram analisados 199 pacientes (sexo masculino - 59%; idade média 61.8 anos), sendo 96 indivíduos (48.2%) com DIL. Através de um modelo de regressão logística multivariado com 7 variáveis independentes, o fenótipo clínico motor do tipo postural instability with gait disorder (PIGD) (OR 0.17, IC 95% 0.07-0.39; p < 0.001), longos períodos de tratamento com L-DOPA (OR 1.31, IC 95% 1.17-1.47; p < 0.001), altas doses diárias equivalentes de L-DOPA (OR 1.00, IC 95% 1.000-1.002; p = 0.04) e a início precoce dos sintomas da 11 DP (OR 1.04, IC 95% 1.01-1.07; p = 0.009) foram os fatores de risco clínicos mais associados ao surgimento de DIL. Dentre os fatores de risco genéticos, apenas o alelo T do SNP rs1799836 no gene da MAOB esteve associado ao aumento na chance de surgimento de DIL (OR 1.51, IC 95% 1.00-2.28; p = 0.05). Nossos resultados mostraram que a predição de surgimento de DIL em pacientes com DP em uso de L-DOPA pode ser feita através de alguns fatores de risco clínicos (fenótipo clínico motor, duração do tratamento com L-DOPA, dose diária equivalente de L-DOPA e idade de início de sintomas) e genéticos, como o SNPrs1799836 no gene da MAOB. Novos estudos com amostras maiores e desenhos prospectivos longitudinais são necessários para se explorar a associação entre estes preditores e o surgimento de DIL. / Parkinson\'s disease (PD) is the second most common neurodegenerative disease in the world, and its treatment is mainly based on drugs involved on dopaminergic neurotransmission in basal ganglia. L-DOPA is the major medication used on the management of PD, but its chronic use is associated with the onset of motor complications, as L-DOPA-induced dyskinesias (LID). LID occur in approximately 50% of patients using L-DOPA over 4 and 6 years, and they cause negative impacts on the quality of life of patients PD. To predict the onset of LID based on clinical and genetic risk may be an useful tool for clinicians which prescribe L-DOPA. The aim of this study was to determinate the main clinical and genetic risk factors for the onset of LID in Brazilian PD patients. A cross-sectional study was conducted with Brazilian PD patients from two centers (Ribeirao Preto and Sao Paulo) as part of the Latin American Research consortium on the Genetics of PD (LARGE-PD), which enrolled only PD patients using L-DOPA. PD patients were submitted to neurological examination and semi-structured interviews performed by movement disorders specialists. Presence of LID was confirmed if UPDRS Part IV had a score >= 1 on item 32. Based on previous studies, we chose eight Single Nucleotide Polymorphisms (SNP) in the following genes: COMT, MAOB, ANKK1, DRD3, DAT1, BDNF, ADORA2A and NOS1. Genotyping was performed using TaqMan SNP genotyping assays. We performed logistic regression and survival analysis to identify clinical and genetic risk factors associated with LID onset We enrolled 199 PD patients (males - 59%; mean age 61.8 years), and 96 patients (48.2%) had LID. At a multivariate model with 7 independent variables, postural instability with gait disorder (PIGD) clinical phenotype (OR 0.17, CI 95% 0.07-0.39; p < 0.001), longer duration of L-DOPA therapy (OR 1.31, Cl 95% 1.17-1.47; p < 0.001), higher L-DOPA equivalent daily doses (OR 1.00, CI 95% 1.000-1.002; p = 0.04), as also as early onset of PD (OR 1.04, CI 95% 1.01-1.07; p = 0.009) were the clinical risk factor more associated with onset of LID. Regarding genetic risk factors, only MAOB SNP rs1799836 was associated with LID, with the T allele increasing the risk of developing LIDs (OR 1.51, CI 95% 1.00-2.28; p = 0.05). Our results showed onset of LID can be predicted based on some clinical (motor clinical phenotype, duration of L-DOPA therapy, L-DOPA equivalent daily dose and age at PD onset) and genetic risk factors, as MAOB SNP rs1799836. Further studies in larger samples, using longitudinal and prospective designs, are needed to explore the association between these predictors and onset of LID.
312

Associação entre polimorfismos em genes relacionados ao metabolismo de folato (RFC1, GCP2, MTHFR e MTHFD1) e alterações nas concentrações de folato, cobalamina e homocisteína em mulheres com história de abortos espontâneos recorrentes / Association between polymorphisms in genes related to folate metabolism (RFC1, GCP2, MTHFR and MTHFD1) and changes in the concentrations of folate, cobalamin and homocysteine in women with a history of recurrent miscarriages

Giusti, Kelma Cordeiro da Silva 16 October 2012 (has links)
O aborto espontâneo recorrente (AER) é caracterizado pela ocorrência de três ou mais abortos consecutivos e acomete 2-4% das mulheres em idade fértil. A etiologia está associada a vários fatores de risco, tais como anomalias uterinas, aberrações cromossômicas, autoimunidade, trombofilias, elevação na concentração de homocisteína (tHcy), porém cerca de 40% dos casos permanece sem causa definida. O metabolismo de unidades de carbono desempenha papel fundamental na disponibilidade de folato na célula, sendo essencial para o desenvolvimento placentário e fetal. Deficiência de vitaminas que regulam este metabolismo, como o ácido fólico, e polimorfismos em genes que codificam enzimas relacionadas ao metabolismo de folato (MTHFR, RFC1, GCP2 e MTHFD1) podem levar à redução das concentrações desta vitamina e ao aumento das concentrações de tHcy. Objetivo foi avaliar a associação entre polimorfismos em genes relacionados ao metabolismo do folato (RFC1, GCP2, MTHFR e MTHFD1) e o risco de se ter AER, bem como avaliar a associação entre estes polimorfismos e as alterações nas concetranções de folato, cobalamina e homocisteína. Foram constituídos três grupos: AER primário: 117 mulheres com AER e nenhum feto viável; AER secundário: 139 mulheres com AER e pelo menos um feto viável; e Controle: 264 mulheres sem história de aborto espontâneo. Nenhuma das mulheres estava grávida no momento da coleta do sangue. Amostras de sangue foram obtidas para dosagens bioquímicas (folato, Cbl, tHcy, entre outras), imunológicas e extração de DNA genômico. As genotipagens foram feitas por PCR-RFLP ou PCR em tempo real. As concentrações séricas de folato e Cbl foram maiores no AER primário e secundário (p<0,05). A distribuição dos genótipos de todos os polimorfismos foi semelhante nos três grupos. O aumento nas concentrações de folato sérico (OR: 1,05, 95% IC: 1,03 - 1,07, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,016), tHcy (OR: 1,03, 95% IC: 0,97 - 1,11, p= 0,033) e T4 (OR: 1,02, 95% IC: 1,00 - 1,03, p= 0,006) e a presença de FAN reagente (1:160) (OR: 2,90, 95% IC: 1,25 - 6,75, p= 0,013) foram considerados fatores de risco para aborto primário. Para o aborto secundário, foram considerados fatores de risco o aumento nas concentrações de folato sérico (OR: 1,04, 95% IC: 1,02 - 1,05, p<0,001), Cbl (OR: 1,00, 95% IC: 1,00 - 1,00, p= 0,019) e tHcy (OR: 1,05, 95% IC: 1,00 - 1,09, p= 0,039), maiores idades (OR: 1,02, 95% IC: 0,98 - 1,06, p= 0,031), hábito de fumar (OR: 2,54, 95% IC: 1,41 - 4,60, p= 0,002) e ter maior IMC (OR:1,42, 95% IC: 1,07 - 1,88, p= 0,015). Os polimorfismos estudados não foram associados ao maior risco de se ter AER, quando analisados isoladamente, e também não foram associados a alterações nas concentrações séricas de folato, Cbl e tHcy, com exceção do genótipo MTHFR 677TT, cujas portadoras apresentaram maior concentração de tHcy, quando comparadas com as portadoras de genótipos 677CC e 677CT nos três grupos. As variáveis concentrações de folato, Cbl, tHcy e T4 e presença de FAN reagente foram associadas ao maior risco de se ter aborto primário. As variáveis idade, IMC, tabagismo, concentrações de folato, Cbl e tHcy foram associadas ao maior risco de aborto secundário. / The recurrent spontaneous abortion (RSA) is characterized by the occurrence of three or more consecutive miscarriages and affects 2-4% of women of childbearing age. The etiology is associated with several risk factors such as uterine abnormalities, chromosomal aberrations, autoimmunity, thrombophilia, increased concentration of homocysteine (tHcy). About 40% of cases remains unknown cause. The units of carbon metabolism plays an essential role in the availability of the cell folate, is essential for the placental and fetal development. A deficiency of the vitamins that regulate this metabolism, like folic acid, and polymorphisms in genes encoding enzymes related to folate metabolism (MTHFR, RFC1, and GCP2 MTHFD1) may lead to decreased concentrations of this vitamin and increased concentrations of tHcy. Objective was to evaluate the association between polymorphisms in genes related to folate metabolism (RFC1, GCP2, MTHFD1 and MTHFR) and the risk of having AER, and to evaluate the association between these polymorphisms and changes in concetranções folate, cobalamin, and homocysteine. Three groups were divided: AER primary: 117 women with RSA and no viable fetus, AER secondary: 139 women with RSA and at least one viable fetus and Control: 264 women with no history of miscarriage. None of the women was pregnant at time of blood collection. Blood samples were taken for biochemical (folate, Cbl, tHcy, etc.), immunological and genomic DNA extraction. The genotyping were carried out by PCR-RFLP or real time PCR. Serum concentrations of folate and Cbl were higher in groups 1 and 2 (p <0.05). The distribution of genotypes of MTHFR c.677C> T, MTHFR c.1298A> C, MTHFD1 c.1958G> A, RFC1 c.80G>GCP2 A and c.1561C> T was similar among the three groups. The increased concentrations of serum folate (OR: 1.05, 95% CI: 1.03 - 1.07, p <0.001), Cbl (OR: 1.00, 95% CI: 1.00 to 1.00, p = 0.016), tHcy (OR: 1.03, 95% CI: 0.97 to 1.11, p = 0.033) and T4 (OR: 1.02, 95% CI: 1.00 to 1.03, p = 0.006) and the presence of ANA (1:160) (OR: 2.90, 95% CI: 1.25 - 6.75, p = 0.013) were considered risk factors primary for abortion. For secondary abortion, were considered risk factors increased the concentrations of serum folate (OR: 1.04, 95% CI: 1.02 - 1.05, p <0.001), cobalamin (OR: 1.00, 95 % CI: 1.00 to 1.00, p = 0.019) and tHcy (OR: 1.05, 95% CI: 1.00 to 1.09, p = 0.039), higher age (OR: 1.02, 95% CI: 0.98 to 1.06, p = 0.031), cigarette smoking (OR: 2.54, 95% CI: 1.41 to 4.60, p = 0.002) and had a higher BMI (OR : 1,42,95% CI: 1.07 to 1.88, p = 0.015). The studied polymorphisms were not associated with increased risk of having RSA when analyzed separately, and were not associated with changes in serum folate, Cbl and tHcy, with the exception of the MTHFR 677TT genotype, whose patients had a higher concentration of total tHcy compared with those with 677CC and 677CT genotypes in the three groups. The variable concentrations of folate, Cbl, tHcy, and T4, presence of ANA and have been associated with increased risk for miscarriage primary. The variables age, BMI, smoking, concentrations of folate, Cbl and tHcy were associated with increased risk of secondary miscarriage.
313

Estudo de caracterização e associação de marcadores moleculares relacionados à leptina para características de crescimento e precocidade de acabamento em bovinos da raça Nelore / Characterization and association of molecular markers linked to leptin with growth and finishing traits in Nelore cattle

Silva, Roulber Carvalho Gomes da 28 January 2008 (has links)
Tendo em vista a possibilidade da utilização de marcadores moleculares relacionados à leptina em programas de melhoramento genético no Brasil, com o objetivo de auxiliar a seleção de bovinos da raça Nelore para características de importância econômica e, particularmente, para aquelas relacionadas ao crescimento e precocidade de acabamento, a proposta do presente trabalho foi caracterizar as freqüências gênicas e genotípicas de alguns polimorfismos e estudar seus efeitos nas características de precocidade de acabamento e crescimento em bovinos da raça Nelore. Foram avaliadas as associações dos marcadores moleculares com medidas de ultra-som de área de olho de lombo (AOL), espessura de gordura subcutânea (EGS), espessura de gordura da picanha (EGP), peso à desmama (PD), peso ao sobreano (PS), ganho de peso da desmama ao sobreano (GPS) e circunferência escrotal ao sobreano (CE). Para a caracterização dos marcadores na população Nelore foram avaliadas as freqüências genotípicas e gênicas, testes de equilíbrio de Hardy-Weinberg, heterozigoses, diversidades alélicas e conteúdos de informação polimórfica. A análise dos efeitos dos diferentes genótipos dos marcadores moleculares foi realizada através da análise de variância, desvios de dominância, efeitos aditivos e efeitos médios de substituição. As freqüências genotípicas e gênicas demonstraram que alguns alelos de determinados marcadores moleculares se encontram em baixa freqüência na população, porém apresentam os mesmos polimorfismos já relatados em bovinos de raças européias. Os marcadores A1457G, C963T e UASMS1 apresentaram associação significativa com características avaliadas por ultra-som. Os marcadores E2JW, A59V e T945M apresentaram associação significativa com características de crescimento. O marcador E2FB apresentou associações significativas apenas pela análise de efeito médio de substituição. Estes achados reforçam o potencial de utilização dos marcadores moleculares ligados a leptina na melhoria das características economicamente importantes em animais da raça Nelore. A seleção assistida por marcadores de animais portadores de alelos favoráveis pode impactar positivamente na cadeia produtiva de bovinos de corte em todos os seus segmentos. / Considering the possibility of utilization of molecular markers linked to leptin in animal breeding programs from Brazil and aiming to aid in the selection of Nellore cattle to economic traits and particularly, for those related to growth and finishing traits, the purpose of this research was to characterize the allelic and genotypic frequencies and associate with growth and finishing in Nellore cattle. There were evaluated the associations of the molecular markers on the ultrasound Longissimus muscle area (AOL), ultrasound backfat thickness (EGS), ultrasound fat thickness in Biceps femoris muscle, weaning weight (PD), yearling weight (PS), weight gain from weaning to yearling (GPS) and yearling scrotal circumference (CE). The characterization of the molecular markers in Nellore cattle was evaluated through of the allelic and genotypic frequencies, Hardy-Weinberg equilibrium tests, heterozigosity, allelic diversity and polymorphism information content. The different genotype effects of the molecular markers were evaluated through ANOVA, dominance deviation, additive and substitution effect. The allelic and genotype frequencies shown some alleles of the molecular markers were low frequencies in Nellore cattle. However there were identified the same polymorphisms described in taurine cattle. Markers A1457G, C963T and UASMS1 demonstrated significant association with ultrasound measurement traits. The E2JW, A59V and T945M markers showed significant association with growth traits. The E2FB marker showed significant effects when it was evaluated for substitution effect. These findings emphasize the potential utilization of molecular markers linked to leptin in the improvement of economic traits in the Nellore cattle. The improvement this traits through marker assisted selection of carrier animals of desirable alleles might positively aid the whole beef cattle productive chain.
314

Polimorfismos nos Genes CYP17, CYP1B1, CYP1A1 e COMT e as Lesões Genômicas Espontâneas em Pacientes com Câncer de Mama / CYP17, CYP1B1, CYP1A1 and COMT Polymorphisms and the Spontaneous Genomic Lesions in Breast Cancer Women

Santos, Raquel Alves dos 22 February 2008 (has links)
O Câncer de Mama (CM) é o segundo tipo mais freqüente de câncer no mundo e a doença maligna mais comum entre as mulheres. Apesar do câncer ser considerado uma típica doença do envelhecimento, o CM apresenta algumas características distintas no que diz respeito às taxas de incidência. Os fatores de risco para o CM incluem idade da menarca precoce e menopausa tardia, terapias hormonais, exposição aos poluentes ambientais, tabagismo e etilismo, no entanto, a exposição prolongada aos estrógenos representa o fator de risco mais importante. A biossíntese e a metabolização dos estrógenos requerem um grande número de vias que são reguladas por uma série de genes cujos polimorfismos têm sido descritos em associação com o CM. Também se sabe que os estrógenos podem danificar a molécula de DNA por aumentar a formação de aductos ou ainda por induzir a 8-hidroxilação de purinas e as quebras de fita simples e duplas do DNA. Dessa forma, o objetivo do presente do presente trabalho foi investigar os níveis de danos no DNA de pacientes com CM antes da quimioterapia ou da radioterapia, a possível associação entre os polimorfismos dos genes metabolizadores de estrógeno CYP17, CYP1B1, CYP1A1 and COMT e o risco ao CM e também a possível influência desses polimorfismos nos níveis espontâneos de danos no DNA. Os linfócitos do sangue periférico de 45 mulheres com diagnóstico para Carcinoma Ductal \"in situ\" ou invasorl e 85 mulheres sadias (controles) foram utilizados para avaliação de danos espontâneos no DNA pelo teste do micronúcleo e Ensaio Cometa. Os resultados mostraram que as freqüências de micronúcleos (MNs) e os danos no DNA detectados pelo Ensaio Cometa foram significativamente maiores no grupo de pacientes do CM do que no grupo controle. Os níveis de danos no DNA foram similares entre fumantes e não-fumantes e a idade não influenciou as freqüências de MNs observadas em pacientes com CM e controles. Para a abordagem molecular a casuística foi de 131 mulheres controles saudáveis e 104 mulheres também com diagnóstico para Carcinoma ductal \"in situ\" ou invasor. A comparação da ocorrência dos polimorfismos estudados nos genes CYP17, CYP1A1 e COMT não mostrou diferenças estatisticamente significativas entre pacientes e controles. Contudo, o genótipo Leu/Leu para o gene CYP1B1 aumentou em três vezes o risco para o CM entre não-fumantes (P = 0,04, OR = 3; 95% intervalo de confiança: 1,1-8,2). Os polimorfismos estudados nos genes citados acima não tiveram associação com a idade da menarca ou da menopausa em pacientes com CM e controles. A possível associação dos polimorfismos nos genes CYP17, CYP1B1, CYP1A1 e COMT sobre os níveis de danos no DNA também foi avaliada e, enquanto o CYP17 e CYP1A1 não afetaram as freqüências de MNs ou os danos no DNA observados pelo Ensaio Cometa nem em pacientes com CM nem no grupo controle, o alelo Leu do CYP1B1 esteve significativamente associado com altos níveis de danos no DNA do grupo controle, mas não interferiu nos danos do DNA detectados no grupo com CM. Em contrapartida, no grupo controle, o indivíduos portadores do alelo Met do gene COMT exibiram níveis mais baixos de danos no DNA quando comparados com o homozigoto selvagem, mas no grupo com CM os indivíduos polimórficos homozigotos (Met/Met) apresentaram níveis de danos no DNA mais elevados do que os seu correspondentes homozigotos selvagens e heterozigotos. Concluindo, este trabalho demonstrou que mulheres com CM apresentam uma instabilidade genômica importante e sugere que os polimorfismos nos genes metabolizadores de estrógenos podem modificar os níveis de danos no DNA tanto em mulheres sadias quanto em mulheres com CM. / Breast cancer (BC) is the second most frequent kind of cancer in worldwide and the most common malignant disease among women. Although cancer is considered a typical aging disease, BC is presenting some distinctive features concerning age-specific incidence rates. Risk factors for breast cancer include early age of menarche and late menopause, hormonal therapies, exposure to environmental pollutants, smoking and alcohol habits, however, increased or prolonged estrogen exposure is the most important risk factor. Estrogen biosynthesis and metabolism requires a great number of enzymatic pathways regulated by different genes with polymorphisms that has been described in association with BC and is well known that estrogens can damage the DNA by increasing the formation of DNA adducts and by inducing 8-hidroxilation of purine bases and breaks in DNA strand. Thus, the aim of the present work was to investigate the levels of DNA damage in BC patients prior chemotherapy or radiotherapy, the possible association of the estrogen metabolizing genes CYP17, CYP1B1, CYP1A1 and COMT polymorphisms on breast cancer risk and also the possible influence of these polymorphisms on the spontaneous levels of DNA damage. Micronucleus test and Comet assay was performed to detect spontaneous DNA damage, using peripheral blood lymphocytes from 45 women diagnosed for Ductal \"in situ\" or invasive breast carcinoma and 85 healthy control women. The results showed that the micronucleus (MNs) frequencies and DNA damage detected by Comet assay were significantly higher in BC group than in controls. The levels of DNA damage were similar in smokers and non-smokers and aging did not influence the frequencies of MNs observed BC patients and in controls. For molecular approach the casuistic comprised of 131 healthy control women and 104 women also diagnosed for Ductal \"in situ\" or invasive breast carcinoma. Comparison of the occurrence of the polymorphisms in CYP17, CYP1A1 and COMT was not statistically different between patients and controls. However, the risk for BC is three-fold increased in non-smokers Leu/Leu group for CYP1B1 (P = 0,04, OR = 3; 95% confidence intervals: 1,1-8,2). The polymorphisms studied in the above mentioned genes did not influence the age of menarche or menopause differently in BC and controls. The influence of CYP17, CYP1B1, CYP1A1 and COMT polymorphisms on the levels of DNA damage was also analyzed and while CYP17 and CYP1A1 did not affect the MNs frequencies or the DNA damage observed by Comet assay in neither in BC nor in control group, the Leu allele of CYP1B1 was significantly associated with the higher levels of DNA damage in control group, but did not interfere on DNA damage detected in BC group. On the other hand in the control group, individuals carrying the Met allele of COMT exhibited lower levels of DNA damage when compared to wild type homozygous, but in BC group the polymorphic homozygous individuals (Met/Met) presented higher levels of DNA than their wild type homozygous or heterozygous counterparts. In conclusion, the present work demonstrated that BC women present an important genomic instability and suggests that estrogens metabolizing polymorphisms may modify the levels of DNA damage in healthy and in BC women.
315

Polimorfismos nos genes da enzima glutationa peroxidase e biomarcadores do estado nutricional relativo ao selênio em população adulta de São Paulo / Polymorfuisms Glutathione Peroxidase genes and biomakers of selenium nutritional status in healthy adults of São Paulo

Donadio, Janaina Lombello Santos 19 September 2011 (has links)
Na maioria das doenças crônicas não transmissíveis (DCNT), consideradas atualmente um sério problema de saúde pública, o estresse oxidativo contribui muito para suas complicações. O principal sistema antioxidante nos mamíferos é o da glutationa peroxidase. Estudos recentes destacaram a relação entre polimorfismos em genes de enzimas antioxidantes e risco para tais doenças. Contudo, como ainda são escassos os dados na literatura sobre a distribuição de diferentes polimorfismos em enzimas antioxidantes na população brasileira, este trabalho se propõe a correlacionar polimorfismos nos genes da glutationa peroxidase com os biomarcadores do estado nutricional relativo ao selênio em uma população adulta. O estudo foi realizado com 124 indivíduos de ambos os gêneros, com idade entre 20 a 50 anos, sem doenças hepáticas, cardiovasculares e câncer. Os participantes responderam um questionário de informações pessoais; o consumo alimentar foi avaliado por três registros alimentares; os marcadores do estado nutricional relativo selênio foram: concentração de Se eritrocitário, Se plasmático e atividade da GPx eritrocitária; e os polimorfismos supracitados foram identificados por PCR em Tempo Real. As médias encontradas para ingestão de Se, foi de 41, I ug/d, para Se no plasma de 54,13ug/L, para Se no eritrócito 56,14ug/L e para atividade da GPx 40,15 U/gHb. Foi observada uma correlação moderadamente positiva entre o selênio no plasma e no eritrócito (r = 0,604). Separando as variáveis entre os gêneros, a média da atividade da GPx foi maior para as mulheres (F = 43,5 U/gHb e M = 34,84 U/gHb, p<0,05). Separando as médias das variáveis bioquímicas entre os diferentes SNPs, só foi encontrada uma diferença significativa para o Se eritrócito e atividade da GPx no SNP Arg5Pro no gene da GPx I, e para o Se plasma e Se eritrócito no SNP4 Pro 126Leu no gene da GPx2. Para os outros SNPs, diferenças estatísticas só foram observadas quando as médias foram separadas pelos gêneros também, e as correlações foram influenciadas tanto pelos genótipos quanto pelo gênero. Os resultados mostrados neste estudo podem ser servir de evidência para destacar a importância em saber a constituição genética dos indivíduos nos estudos utilizando as variáveis Se plasmático, Se eritrocitário e atividade da GPx, como biomarcadores do estado nutricional relativo ao selênio. / In the majority of non-communicable chronic diseases (NTCD), considered today a serious public health problem, the oxidative stress contributes much to its complications. The main antioxidant system in mammals is the glutathione peroxidase. Recent studies have highlighted the relationship between polymorphisms in antioxidant enzymes genes and risk for such diseases. However, as there are very few data in the literature on the distribution of different polymorphisms in antioxidant enzymes with the brazilian population, this study proposes to correlate polymorphisms of glutathione peroxidase with biomarkers of selenium nutritional status in a healthy population. The study was conducted with 124 individuais of both genders, aged between 20 to 50 years, without Iiver disease, cardiovascular disease, and cancer. The participants answered a questionnaire of personal information; the food consumption was assessed by three feeding records; the markers of selenium nutritional status were: concentration of erythrocytes, plasma and erythrocyte GPx activity; the polymorphisms have been identified by Real Time PCR. The averages of selenium intake were of 41.1 ug/d, for plasma selenium concentrations 54.13 ug/L, for erythrocyte selenium concentrations 56.14 ug/L and for erythrocites GPx activity 40.15 U/gHb. There was a positive moderately correlation between plasma selenium and erythrocyte selenium (r = 0.604 ). Separating the variables between genders, the average ofthe activity ofthe GPx was higher for women (F = 43.5 U/g Hb and M = 34.84 U/g Hb, p<0.05 ). Separating the averages of biochemical markers between different genotypes, there was only a significant difference in erythrocyte selenium and GPx activity in Arg5Pro (GPxl gene), and for plasma and erythrocyte selenium in Pro126Leu (GPx2 gene). For the other SNPs, statistical differences were only observed when means were separated by the gender, and the correlations were influenced by both genotypes and by gender.
316

Neurogênese e esquizofrenia: estudo molecular de associação / Neurogenesis and schizophrenia: molecular association study

Purim, Sheila Gregório 28 July 2006 (has links)
A esquizofrenia (EZ) é uma das doenças neuropsiquiátricas mais prevalentes, afetando cerca de 1% da população ao redor do mundo, sendo caracterizada pela presença de delírios, alucinações, disfunção cognitiva e apatia, entre outros. Dentre as hipóteses que procuram explicar as bases biológicas da EZ, a que tem tido um maior embasamento e credibilidade é a Hipótese do Neurodesenvolvimento, que afirma que a EZ é uma desordem de desenvolvimento do sistema nervoso central, originada nos estágios intermediários da vida intra-uterina. Ao mesmo tempo o envolvimento de componentes genéticos em EZ é fortemente sugerido, principalmente por estudos envolvendo gêmeos e famílias. Uma série de estudos de ligação, realizados com famílias contendo indivíduos afetados, têm apontado para diferentes locos cromossômicos que devem estar associados à EZ. Enquanto tais estudos sugerem locos candidatos, a descoberta dos genes envolvidos com a doença, mapeados nestes locos, trará grande progresso ao estudo da genética da EZ. Dessa forma, o objetivo deste estudo foi analisar a possível associação entre polimorfismos em genes envolvidos com neurodesenvolvimento, mapeados em locos importantes sugeridos por estudos de ligação, e a EZ. Após uma série de análises in silico e validações in vitro, um total de 41 polimorfismos, mapeados em 39 genes candidatos, foram selecionados neste estudo. Estes polimorfismos foram genotipados em amostras de DNA, obtidas de 200 pacientes esquizofrênicos e 200 controles da população Brasileira. Uma análise individual das freqüências genotípicas e alélicas de cada polimorfismo identificou quatro polimorfismos como associados à EZ, mapeados nos genes AKT1, MAP1B, FZD3, e NUMBL. Em seguida, esses quatro polimorfismos foram analisados em um segundo set amostral, composto por amostras de DNA de casos e controles Dinamarqueses, de forma a tentar replicar os achados com a amostra Brasileira. Para dois destes polimorfismos (NUMBL e FZD3) observamos uma tendência de associação na amostra dinamarquesa, o que reforça o possível envolvimento destes polimorfismos com a EZ. Avançamos na caracterização haplotípica do SNP de FZD3 em amostras do Brasil e da Dinamarca e também investigamos as conseqüências funcionais deste SNP, utilizando ensaios de gene-repórter em duas diferentes linhagens celulares. Por fim, uma análise multilocus preliminar, utilizando o método set association, foi realizada para os marcadores bialélicos por nós avaliados (SNPs e indels), a fim de identificar a existência de um set de genes que estivessem contribuindo em conjunto para a etiologia da EZ. Os resultados dessa análise apontaram para o efeito aditivo de 5 genes para a etiologia da EZ: FZD3, AKT1, MAP1B, SEMA6C e ADAM28. Os genes encontrados em nosso estudo como associados à EZ, tanto pela análise individual quanto pela análise multilocus, se encontram envolvidos direta ou indiretamente com as vias sinalizadoras de WNT e NOTCH, sugerindo o envolvimento destas duas vias sinalizadoras para a etiologia da doença. / Schizophrenia (SZ) is one of the most prevalent neuropsychiatry disorders, affecting about 1% of the world\'s population. SZ is characterized by the presence of delirium, hallucinations, cognitive dysfunction, apathy, etc. Among the hypotheses that try to explain the biological basis of SZ, the Neurodevelopment Hypothesis is one of the most accepted. This hypothesis states that SZ is a neurodevelopment disorder, originated during intermediate stages of the intrauterine life. On the other hand, the involvement of genetic components in the etiology of SZ has been suggested by twin and family studies. A series of linkage studies pointed different genomic loci associated with the disease. While these studies suggest candidate loci, the determination of which genes/genetic alterations inside these loci are involved with the disease will bring great progress to the study of SZ genetics. The objective of this study was to analyze the possible associations between DNA polymorphisms in genes related to neurodevelopment and mapped to genomic loci previously associated with SZ. After a series of in silico and experimental analysis, a total of 41 polymorphisms, mapped to 39 candidate genes, were selected for analysis. These polymorphisms were genotyped in DNA samples obtained for 200 SZ patients and paired 200 controls from the Brazilian population. An individual analysis of the genotypic and allelic frequencies of each polymorphism identified 4 polymorphisms as associated with SZ, mapped in the AKT1, MAP1B, FZD3, and NUMBL genes. These four polymorphisms were then analyzed in a second set of samples, derived from Danish cases and controls. A trend for association was observed for two of these polymorphisms (FZD3 and NUMBL), reinforcing their putative association with EZ. Haplotipic analysis was performed for the FZD3 SNP and its functional consequences were confirmed in two different cell lines by using gene reporter assays. Finally, multilocus analysis, performed by the use of the set association method, pointed to an additive effect of 5 genes contributing to the etiology of SZ: FZD3, AKT1, MAP1B, SEMA6C e ADAM28. All the genes pointed by our study as associated with SZ, by both the individual and the multilocus analysis, are directly or indirectly involved in the WNT and NOTCH pathways, which strongly suggests the involvement of these pathways in the etiology of SZ.
317

Anthropometric, biochemical and hormonal interrelationships in essential hypertension. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Based on previous studies, the increasing prevalence of hypertension may be associated with factors such as obesity, dietary salt and fat intake. This study examined the common biochemical and anthropometric markers that are associated with blood pressure elevation, increasing metabolic and haemodynamic derangement in subjects in Hong Kong, and related those phenotypic markers to some genetic polymorphisms relevant to hypertension. / Five hundred and thirty nine Hong Kong Chinese subjects were examined. They were aged from 20 to 60 years, and were hypertensive or normotensive siblings from families with a hypertensive proband, and normotensive controls without a family history of hypertension. The interrelationships between pathophysiological changes and various neurohormones considered relevant to the development of hypertension were investigated. Fasting blood and 24 hour urine samples were collected. Plasma insulin, plasma leptin, plasma renin activity (PRA), serum angiotensin converting enzyme (ACE) activity, aldosterone, 24 hour urine noradrenaline, adrenaline, dopamine and kallikrein were measured. A robust assay for the measurement of urine free cortisol and cortisone and 6beta-hydroxycortisol by an LC-MS/MS method was developed and validated. The ratio between urine free cortisol and cortisone was used as an estimate of the activity of 11beta-hydroxysteroid dehydrogenase type II (11betaHSD2) for cortisol metabolism. These parameters were related to polymorphisms in three genes, the angiotensinogen (AGT) gene M23 5T, the dopamine D1 receptor (DD1R) gene A-48G and the dopamine D2 receptor (DD2R) gene Taq1 A polymorphisms. Analysis of variance was employed for the parameters in the three groups of subjects and for an age-matched sibling pair analysis (using 1 normotensive and 1 hypertensive sibling from each family). Comparisons between parameters were also made after dividing the whole population into 3 groups according to the tertiles of blood pressure. (1) Central (higher waist to hip ratio and waist circumferences) and general (greater body mass index and weight) obesity were found in both hypertensive patients and the normotensive siblings compared to the control subjects. These obesity indices showed strong positive relationships with increased insulin resistance and blood pressure. The obesity indices were also independently associated with systolic and diastolic blood pressure, with central obesity showing the stronger associations. (2) Hypertensives had more adverse lipid profiles, insulin resistance and higher fasting plasma glucose levels. This suggested that the blood pressure elevation in the hypertensives may be mediated through obesity and insulin resistance. (3) Both the hypertensive and normotensive members of sibling pairs had lower noradrenaline and cortisol excretion and higher activity of 11betaHSD2 compared to the normotensive controls. The result showed positive relationships between noradrenaline and increased obesity, insulin resistance and blood pressure, while the relationship between adrenaline and blood pressure was inversed. (4) Lower plasma ACE activity and aldosterone were found in the hypertensives and their siblings than in the normotensive controls. There was a reduction in PRA across the blood pressure tertiles as blood pressure increased. In addition to the higher 11betaHSD2 activity, a negative relationship between aldosterone and blood pressure in hypertensive siblings was observed. These findings may indicate the protective mechanism of these systems in this population. In subjects with the different polymorphisms of AGT M235T, there were no differences in the PRA, serum ACE activity or aldosterone, but lower urine cortisol and kallikrien were found in relation to increasing numbers of the T allele. There was a weak association between the AGT M235T polymorphism and hypertension. (5) Despite the strong correlation of dopamine excretion between hypertensive and normotensive siblings within families, lower dopamine levels were found in the normotensive siblings. A consistent positive relationship was found between urine dopamine and sodium excretion, which supports the concept of the natriuretic effect of dopamine. There was no phenotypic difference found in any of the biochemical parameters in relation to the DDIR A-48G and DD2R Taq1 A polymorphisms, but there were weak associations with blood pressure and these polymorphisms in the sibling study. / The normotensive siblings had metabolic abnormalities similar to but less severe than the hypertensive probands, which suggests that the genetic effects and interacting effect of shared lifestyle and environmental factors with their hypertensive family member may be influential on the healthy siblings. Adaptive changes were seen in some of the blood pressure regulating systems in both the hypertensive probands and the normotensive siblings. The major factors predisposing to the hypertension in these subjects appeared to be obesity and insulin resistance and the adaptive changes were insufficient to compensate for these in the hypertensive subjects. / Chu Ten Wah Tanya. / "March 2006." / Adviser: Brian Tom Linson. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1547. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 304-341). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
318

Interleukin-10 promoter single nucleotide polymorphism in non-Hodgkin's lymphoma and diffuse large B-cell lymphoma.

January 2006 (has links)
Ko Kin Ming Jeffery. / Thesis submitted in: July 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 99-111). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.ix / List of Tables --- p.xiii / List of Figures --- p.xv / List of Abbreviations --- p.xvi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Malignant Lymphoma --- p.1 / Chapter 1.2 --- Non-Hodgkin's Lymphoma --- p.1 / Chapter 1.3 --- Diffuse Large B-cell Lymphoma --- p.2 / Chapter 1.3.1 --- General Features of Diffuse Large B-cell Lymphoma --- p.2 / Chapter 1.3.2 --- Morphologic variants of Diffuse Large B-cell Lymphoma --- p.4 / Chapter 1.3.2.1 --- Centroblastic vairant --- p.5 / Chapter 1.3.2.2 --- Immunoblastic variant --- p.5 / Chapter 1.3.2.3 --- Anaplastic variant --- p.6 / Chapter 1.3.3 --- Immunophenotype of Diffuse Large B-cell Lymphoma --- p.6 / Chapter 1.3.3.1 --- Lineage-associated antigens --- p.6 / Chapter 1.3.3.1.1 --- B-cell lineage antigens --- p.6 / Chapter 1.3.3.1.2 --- T-cell lineage antigens --- p.7 / Chapter 1.3.3.2 --- Antigen involved in regulation of cell proliferation and apoptosis --- p.8 / Chapter 1.3.3.2.1 --- Proliferation markers --- p.8 / Chapter 1.3.3.2.2 --- Cell cycle regulators --- p.8 / Chapter 1.3.3.2.3 --- Protein controlling apoptosis --- p.10 / Chapter 1.3.4 --- Subtypes of Diffuse Large B-cell Lymphoma --- p.10 / Chapter 1.3.4.1 --- Classification method of DLBCL subtypes --- p.11 / Chapter 1.3.4.1.1 --- DNA microarray --- p.11 / Chapter 1.3.4.1.2 --- Immunohistochemistry pattern --- p.14 / Chapter 1.3.4.1.2.1 --- CD10 --- p.16 / Chapter 1.3.4.1.2.2 --- Bcl-6 --- p.16 / Chapter 1.3.4.1.2.3 --- CD138 --- p.17 / Chapter 1.3.4.1.2.4 --- MUM1/IRF4 --- p.17 / Chapter 1.3.4.2 --- Prognosis of 、DLBCL subtypes --- p.19 / Chapter 1.4 --- Interleukin 10 --- p.22 / Chapter 1.4.1 --- The IL-10 gene --- p.23 / Chapter 1.4.2 --- IL-10 promoter --- p.23 / Chapter 1.5 --- IL-10 receptor --- p.24 / Chapter 1.6 --- Cellular Signaling Pathways Regulated by IL-10 --- p.25 / Chapter 1.6.1 --- Jak/Stat Pathway --- p.25 / Chapter 1.6.2 --- Inhibition of NF B pathway --- p.26 / Chapter 1.7 --- Function of IL-10 --- p.27 / Chapter 1.7.1 --- Effects of IL-10 on immune cells in vitro --- p.27 / Chapter 1.7.2 --- Effects of IL-10 on B-cells --- p.28 / Chapter 1.8 --- IL-10 and IL-10 receptor in malignant diseases --- p.29 / Chapter 1.8.1 --- Melanoma --- p.29 / Chapter 1.8.2 --- Carcinoma --- p.30 / Chapter 1.8.3 --- Lymphoma --- p.30 / Chapter 1.9 --- Single Nucleotide Polymorphism (SNP) --- p.33 / Chapter 1.9.1 --- SNPs in cancer research --- p.34 / Chapter 1.9.1.1 --- Susceptibility to cancer and SNPs --- p.35 / Chapter 1.9.1.2 --- Outcome and SNPs --- p.35 / Chapter 1.10 --- SNP in the IL-10 promoter --- p.36 / Chapter 1.11 --- IL-10 promoter SNP in DLBCL --- p.37 / Chapter Chapter 2: --- Aims of Study --- p.39 / Chapter Chapter 3: --- Materials and Methods --- p.41 / Chapter 3.1 --- Sample Recruitment --- p.41 / Chapter 3.2 --- DNA preparation for Single Nucleotide Polymorphism (SNP) analysis --- p.41 / Chapter 3.2.1 --- Isolation of Peripheral Blood Mononuclear Cell (PBMC) from buffy coat from blood of normal control group --- p.41 / Chapter 3.2.2 --- Preparation for NHL and DLBCL samples from paraffin-embedded sections for DNA extraction --- p.42 / Chapter 3.2.3 --- DNA extraction for SNP analysis --- p.42 / Chapter 3.3 --- SNP analysis by Restriction Fragment Length Polymorphism (RFLP) --- p.43 / Chapter 3.3.1 --- Amplification of target site by PCR --- p.43 / Chapter 3.3.2 --- SNP analysis --- p.45 / Chapter 3.4 --- Determination of haplotypic frequency --- p.50 / Chapter 3.5 --- Classification of DLBCL by immunohistochemistry --- p.50 / Chapter 3.5.1 --- Staining pattern of CD10 --- p.53 / Chapter 3.5.2 --- Staining pattern of Bcl-6 --- p.54 / Chapter 3.5.3 --- Staining pattern of CD138 --- p.55 / Chapter 3.5.4 --- Staining pattern of MUM1/IRF4 --- p.56 / Chapter 3.6 --- Statistical Analysis --- p.57 / Chapter Chapter 4: --- Results --- p.58 / Chapter 4.1 --- SNPs of IL-10 promoter in normal controls --- p.58 / Chapter 4.1.1 --- Allelic Frequencies and genotype distributions --- p.58 / Chapter 4.1.2 --- Haplotypic Frequencies of normal controls --- p.58 / Chapter 4.2 --- SNP of the IL-10 promoter in non-Hodgkin's lymphomas --- p.59 / Chapter 4.2.1 --- Allelic frequencies and genotype distributions --- p.59 / Chapter 4.2.2 --- Haplolypic frequencies --- p.61 / Chapter 4.4 --- SNPs of the IL-10 promoter in DLBCL --- p.62 / Chapter 4.4.1 --- Allelic frequencies and genotype distributions --- p.62 / Chapter 4.4.2 --- Haplotypic frequencies --- p.64 / Chapter 4.5 --- SNP of the IL-10 promoter in different subtypes of DLBCL --- p.65 / Chapter 4.5.1 --- Classification of DLBCL by immunohistochemistry --- p.65 / Chapter 4.5.2 --- SNP of the IL-10 promoter in Germinal Center DLBCL (GC-DLBCL) --- p.67 / Chapter 4.5.2.1 --- Allelic frequencies and genotype distributions --- p.67 / Chapter 4.5.1.2 --- Haplotypic frequencies --- p.69 / Chapter 4.5.2 --- SNP of the IL-10 promoter in Activated Germinal Center DLBCL (AGC-DLBCL) --- p.70 / Chapter 4.5.2.1 --- Allelic frequencies and genotype distributions --- p.70 / Chapter 4.5.2.2 --- Haplotypic frequencies --- p.72 / Chapter 4.5.3 --- SNP of the IL-10 promoter in Activated non-Germinal Center DLBCL (ANGC-DLBCL) --- p.73 / Chapter 4.5.3.1 --- Allelic frequencies and genotype distributions --- p.73 / Chapter 4.5.3.2 --- Haplotypic frequencies --- p.75 / Chapter 4.5.4 --- SNP of the IL-10 promoter in Unclassified DLBCL (UC-DLBCL). --- p.76 / Chapter 4.5.4.1 --- Allelic frequencies and genotype distributions --- p.76 / Chapter 4.5.4.2 --- Haplotypic frequencies --- p.78 / Chapter 4.6 --- Summary of SNP of the IL-10 promoter in DLBCL subtypes --- p.79 / Chapter 4.7 --- Overall survival analysis --- p.80 / Chapter 4.7.1 --- Clinical data of DLBCL --- p.80 / Chapter 4.7.2 --- Cox Proportional Hazards Regression Analysis in DLBCL --- p.81 / Chapter Chapter 5: --- Discussion --- p.88 / Chapter 5.1 --- SNP for low IL-10 production in Hong Kong population --- p.88 / Chapter 5.2 --- NHL in low IL-10 production population --- p.90 / Chapter 5.2.1 --- The relationship between IL-10 and NHL --- p.90 / Chapter 5.2.2 --- Allelic frequencies and haplotype of the IL-10 promoter in NHL --- p.90 / Chapter 5.3 --- Classification of DLBCL --- p.91 / Chapter 5.3.1 --- Current prognostic analysis --- p.91 / Chapter 5.3.2 --- DLBCL subtypes distribution in Hong Kong is different from Caucasian --- p.92 / Chapter 5.4 --- IL-10 and DLBCL --- p.93 / Chapter 5.5 --- SNP of IL-10 promoter in DLBCL subtypes --- p.94 / Chapter 5.5.1 --- Allelic frequencies and haplotype of DLBCL subtypes --- p.94 / Chapter 5.5.2 --- Rare haplotypes were discovered in DLBCL --- p.94 / Chapter 5.6 --- Overall survival Analysis --- p.95 / Chapter 5.6.1 --- Univariate Cox Proportional Hazards Regression Analysis --- p.95 / Chapter 5.6.2 --- Bivariate Cox Proportional Hazards Regression Analysis --- p.96 / Chapter Chapter 6: --- Conclusion --- p.97 / References --- p.99
319

Marcadores de resposta ao sildenafil no tratamento da disfunção erétil: genes relacionados à dimetilarginina assimétrica / Markers of sildenafil responsiveness in the treatment of erectile dysfunction: asymmetric dimethylarginine related genes

Ana Maria Milanez Azevedo 10 March 2017 (has links)
A disfunção erétil (DE) é uma doença relacionada com a sinalização deficiente de óxido nítrico (NO). O NO é produzido a partir da L-arginina pelas enzimas óxido nítrico sintase neuronal (nNOS), endotelial (eNOS) e induzida (iNOS). A dimetilarginina assimétrica (ADMA) é um inibidor endógeno dos três subtipos existentes de NOS, e é metabolizada principalmente pelas enzimas dimetilarginina dimetilaminohidrolase 1 e 2 (DDAH1 e DDAH2). Vários estudos têm associado alterações em genes, expressão ou atividade das enzimas DDAH com distúrbios em que a sinalização de NO é prejudicada. O objetivo deste estudo foi avaliar se o nível de resposta ao tratamento da DE com sildenafil pode estar associado a polimorfismos dos genes DDAH1 (rs1554597 e rs18582) e DDAH2 (rs805304 e rs805305) e, também, aos haplótipos formados por estes polimorfismos. Foram selecionados 70 pacientes com DE pós-prostatectomia (DEPP) e 70 pacientes com DE clínica (DEC). A função erétil dos voluntários foi avaliada através do questionário Índice Internacional de Função Erétil (IIEF). Para avaliação da resposta ao sildenafil, foram calculadas a diferença entre as pontuações pré e pós-tratamento (?IIEF) e a percentagem atingida da máxima resposta possível (?IIEF%) de cada paciente. Também, os pacientes de cada grupo foram divididos em bons e maus respondedores ao sildenafil de acordo com a mediana dos valores de ?IIEF%. Os genótipos dos rs1554597, rs805304 e rs805305 foram obtidos pela técnica de reação em cadeia da polimerase (PCR) seguida de digestão enzimática, e do rs18582 pela técnica de PCR alelo específica. O software PHASE 2.1 foi utilizado para estimar os haplótipos em cada grupo. Os resultados mostraram que o alelo variante A do rs18582 apresentou tendência para associação com piores respostas ao sildenafil no grupo DEC (P=0,058). No grupo DEPP, portadores dos alelos variantes A do rs805304 e G do rs805305 foram associados a melhores respostas ao sildenafil (?IIEF, P=0,007; ?IIEF%, P=0,025; e score IIEF pós-tratamento, P=0,014). Não foram encontradas outras associações significativas. Estes resultados mostram que os marcadores genéticos rs805304 e rs805305 do DDAH2 podem influenciar as respostas ao sildenafil em pacientes com DE. / Erectile dysfunction (ED) is a disease related to deficient nitric oxide (NO) signaling. NO is produced from L-arginine by three isoforms of the enzyme nitric oxide synthase: neuronal (nNOS), endothelial (eNOS) and induced (iNOS). Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of the three existing NOS subtypes, and is metabolized primarily by dimethylarginine dimethylaminohydrolase 1 and 2 (DDAH1 and DDAH2) enzymes. Several studies have associated changes in genes, expression or activity of DDAH enzymes with disorders in which NO signaling is impaired. The aim of this study was to evaluate whether the response to ED treatment with sildenafil may be associated with polymorphisms of the DDAH1 (rs1554597 and rs18582) and DDAH2 genes (rs805304 and rs805305), as well as the haplotypes formed by these polymorphisms. We selected 70 patients with postprostatectomy ED (PPED) and 70 patients with clinical ED (CED). The erectile function of the volunteers was assessed using the International Index for Erectile Function (IIEF) questionnaire. To evaluate the response to sildenafil, the difference between the pre- and post-treatment scores (?IIEF) and the percentage reached from the maximum possible response (?IIEF%) of each patient were calculated. Also, patients from each group were divided into good and bad responders to sildenafil according to the median values of ?IIEF%. The genotypes of rs1554597, rs805304 and rs805305 were obtained by the polymerase chain reaction (PCR) technique followed by enzymatic digestion, and rs18582 by the allele-specific PCR technique. The PHASE 2.1 software was used to estimate the haplotypes in each group. The results showed that the variant A allele of rs18582 showed a tendency to be associated with a greater chance of worse responses to sildenafil in the DEC group (P=0,058). In the DEPP group, carriers of the variant alleles A of rs805304 and G of rs805305 were associated with better responses to sildenafil (?IIEF, P=0,007; ?IIEF%, P=0,025; and post-treatment IIEF score, P=0,014). No other significant associations were found. These results show that the genetic markers rs805304 and rs805305 of DDAH2 may influence the responses to sildenafil in patients with ED.
320

A influência de polimorfismos de fatores de restrição na suscetibilidade ao HIV e na progressão à Aids

Polo, Tiago Antonio January 2017 (has links)
Fatores de restrição são as primeiras proteínas celulares envolvidas no combate a infecções virais, são considerados uma defesa intrínseca das células, constituindo-se em uma rápida resposta frente a invasão de patógenos. Essas moléculas são bastante diversas e são capazes de interferir em algum ponto do ciclo viral, atenuando ou bloqueando a evolução da infecção. Após a descoberta da existência desses fatores, alguns estudos têm direcionado o foco para as possíveis alterações genéticas que podem influenciar a estrutura dessas proteínas e, deste modo, interferir sobre suscetibilidade e progressão de doenças infecciosas, como a infecção pelo HIV/aids. O objetivo do presente estudo foi avaliar três SNPs de três diferentes fatores de restrição (o TRIM5α – rs10838525, a APOBEC3F – rs2076101 e o CUL5 – rs7117111) e observar suas frequências em diferentes grupos étnicos, bem como a associação desses fatores com a suscetibilidade ao HIV e a progressão a aids, em um grupo de soronegativos e soropositivos. Foram selecionados 345 indivíduos HIV+ atendidos no setor de Infectologia do Hospital Nossa Senhora da Conceição e 324 indivíduos HIV– doadores de sangue do Hospital de Clínicas de Porto Alegre. Os SNPs foram identificados através da técnica de PCR TaqManTM. O teste qui-quadrado foi utilizado para a análise das frequências e por regressão logística univariada foi avaliado o OR com 95% de IC entre os modelos dominantes e recessivos. Entre os SNPs estudados apenas o rs7117111 apresentou resultado estatisticamente significativo para o genótipo GG em relação a proteção ao HIV-1 (OR 0,661, IC 95% 0,449-0,974, P=0,036) e esse mesmo genótipo, também, parece estar relacionado aos progressores rápidos, pois apresentou uma tendência nessa relação quando ajustado pela etnia (OR ajustado 2,115, IC 95% 0,990- 4,520, P=0,053). Tais achados demonstram que alterações genéticas, especificamente no gene CUL5, podem influenciar a suscetibilidade ao HIV-1 e podem, também, interferir na progressão a aids. Esses resultados geram questionamentos de grande valia para um maior entendimento da influência genética do sistema de defesa intrínseco celular no curso da infecção. / Host restriction factors are the first cellular proteins engaged in antiviral response, they are considerate an intrinsic cell defense with the aim to be a rapid answer against the invasion of pathogens. This molecules have a vary diversity in structure and each one act in a distinct stages of viral life cycle, however always with the same objective to attenuate or block the infection. After the discovery of this restriction factors, some researches focus in looking for genetic variation that can be influence in structure protein and with this way interfere in HIV susceptibility or progress to AIDS. The aim of present work was evaluate tree SNPs of tree different restrictions factors (TRIM5α – rs10838525, APOBEC3F – rs2076101 and CUL5 – rs7117111) and detect yours frequencies in different ethics group, as well as, evaluate the SNPs`s capacity in influence the susceptibility to HIV and progress to AIDS in a seronegative and seropositive groups. For this research was selected 345 samples of HIV+ individuals from the Infectology sector of Nossa Senhora da Conceição hospital and 324 HIV- samples from blood donors of Clinics Hospital of Porto Alegre. Through PCR TaqManTM assay the SNPs was genotyping. The qui-square test was used to analyze the frequencies and by unvaried logistic regression was estimate the OR with 95% CI to dominant and recessive models. Between the tree SNPs chosen only rs7117111 was statistically significant the GG genotype with the HIV-1 protection (GG, OR: 0,661, 95% CI 0,449-0,974, P=0.036) and this same genotype seems to be to related with rapid progress to AIDS, because the result shows a tendency when adjusted for ethnicity in the recessive model (adjusted OR 2,115, IC 95% 0,990-4,520, P=0,053). This finds shows the genetics alterations, specify in the CUL5 gene, can alter the susceptibility to HIV-1 and can interfere in the progress to AIDS. Theses results are also important for the understanding of the genetic alterations in the host antiviral intrinsic mechanisms anti-HIV and can bring new insights for strategies against HIV pandemic.

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