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Desenvolvimento computacional de um inibidor das proteínas midkina e glutationa s-transferase. / Computational development of a midkina and glutationa s-transferase protein inhibitor.SILVA, Rafaela Bezerra da. 26 July 2018 (has links)
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Previous issue date: 2015-07-23 / CNPq / O desenho racional de fármacos tem sido largamente utilizado para o desenvolvimento de medicamentos mais eficazes no tratamento de diversas doenças, inclusive o câncer. Este termo é utilizado para o conjunto de doenças ocasionadas pelo crescimento desordenado de células, que invadem tecidos e órgãos do próprio organismo, podendo se espalhar por todo o corpo, processo denominado metástase. Entre as diversas pesquisas direcionadas à formação de novas drogas para o tratamento de tumores está a terapia alvo molecular que se baseia na utilização de fármacos que inativam uma determinada proteína de uma célula cancerígena. A Biologia Molecular identificou várias proteínas relacionadas com o câncer, dentre estas estão a midkina (MK) e a glutationa S-transferase da classe Pi (GSTP1), associadas à capacidade de multiplicação e à resistência dos tumores, respectivamente. O desenvolvimento de um inibidor que apresente especificidade tanto para a MK quanto para a GSTP1 possibilitará um tratamento sem prejuízos às células normais e uma melhor qualidade de vida aos pacientes cancerosos. O presente trabalho objetivou projetar uma molécula capaz de inibir as atividades biológicas da MK e da GST na referida patologia. Utilizando como recursos o site de busca Protein Data Banc (PDB) para a obtenção das estruturas tridimensionais estudadas, o Basic Local Alignment Search Tool (BLAST) para alinhamento e análise das sequências protéicas, o software Hex 8.0 para a realização dos testes de docking molecular e o WinCoot 0.7.1 para a identificação das interações intermoleculares hidrofóbicas e de hidrogênio analisadas nos complexos gerados. Para o desenvolvimento da molécula foram utilizados como modelo os inibidores 6-(7-Nitro-2,1,3-Benzoxadiazol-4-Ylthio) Hexanol (NBDHEX) e o 5-propiltio-1H-benzimidazol-2-il) carbamato (albendazol). O inibidor desenvolvido (RBT15) foi projetado através de estruturas previamente depositadas no PDB e recortadas para atenderem as características topológicas dos receptores. Os testes analisados evidenciaram que o ligante RBT15 é energeticamente mais favorável e demonstrou interação com um maior número de resíduos de interesse que os outros dois inibidores analisados. Os dados sugerem que a estrutura desenvolvida pode vir a ser um potencial inibidor das proteínas MK e GSTP1. Sendo, por esse motivo, uma promissora molécula para o desenvolvimento de fármacos mais eficientes e menos invasivos para o tratamento de câncer. / The rational design of drugs has been widely used for drug development more effective in the treatment of various diseases, including cancer. This term used and hair diseases caused set cluttered cell growth, tissues and organs to invade que own body and can spread throughout the body, process called metastasis. Between how several research aimed at new training drugs for tumor treatment is molecular target therapy, which is based on the use of drugs that inactivate a particular cancer cell protein. Molecular biology has identified several proteins related to cancer, among these are Midkina (MK) and Glutathione S-Transferase Pi class (GSTP1), associated with the multiplication capacity and resistance of tumors, respectively. The development of a specific inhibitor that present both for GSTP1 and MK as to enable a free damage to normal cells treatment and better quality of life for cancer patients. This study aimed to design a molecule capable of inhibiting the biological activity of MK and GST in that condition. Using resources like search website Protein Data Bank (PDB) for obtaining the studied three-dimensional structures, the Basic Local Alignment Search Tool (BLAST) for alignment and analysis of protein sequences, the Hex 8.0 software for the realization of molecular docking test and WinCoot 0.7.1 to identify the hydrophobic intermolecular interactions and hydrogen generated in the analyzed complexes. For the development of the molecule were used as the template inhibitors 6-(7-nitro-2, 1, 3-benzoxadiazol-4-Ylthio) Hexanol (NBDHEX) and 5-propylthio-1H-benzimidazol-2-yl) carbamate (Albendazol). The developed inhibitor (RBT15) was designed using previously deposited in PDB structures and trimmed to meet the topological characteristics of the receivers. The tests showed that the analyzed RBT15 binder is energetically more favorable and demonstrated interaction with a larger number of residues of interest than the other two analyzed inhibitors. The data suggest that the developed structure might be a potential inhibitor of GSTP1 and MK proteins. Since, therefore, a promising molecule for the development of more efficient and less invasive drugs for the treatment of cancer.
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Effects of Environmental Tobacco Smoke and CYP2A6 and GSTP1 Exposure on Childhood WheezeBiagini Myers, Jocelyn Marie 22 August 2008 (has links)
No description available.
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Case-only study of interactions between specific genetic polymorphisms and cigarette smoking in the aetiology of Parkinson's diseaseDeng, Yifu January 2005 (has links)
The aetiology of Parkinson's disease (PD) is still unclear. Research findings suggest that both environmental and genetic factors may contribute to its development. The interactions between genes and the environment might exist and play a key role. Cigarette smoking was found to be one of the few factors exhibiting a protective effect. If chemical compounds found in cigarette smoke influence PD risk, the difference in the ability of certain individuals in metabolising these substances might alter their susceptibility to the risk of developing PD. Many metabolic enzyme genes exhibit polymorphic traits with alteration of gene function. These might be associated with an altered susceptibility of individuals to PD. Few studies have examined the hypothesis that metabolic enzyme gene polymorphisms might modulate the effect of smoking on PD risk. However, it is crucial to consider these potential interactions when we try to elucidate the aetiology of PD. Even if each factor only contributes a slight variation and influences a small portion of the whole population, non-linear and unpredictable interactions may account for a high proportion of the aetiological fraction. Previous studies have not been strictly designed to examine the interactions between smoking and metabolic enzyme genetic polymorphisms. These studies have not been able to elucidate the extent of the interaction. Therefore, this PhD project attempted to examine whether genetic factors, operating in the phase one and phase two metabolic pathways, interact with smoking to influence the development of PD. This is the first genetic epidemiological study of PD specifically addressing this issue. The research aids in further understanding the aetiology of PD and may be useful for identifying people at higher risk. A case-only design was chosen for this project for two reasons: first, PD is a relatively rare disease and the case-only design is much more efficient at detecting gene-environment interactions; second, the PD cases for the project were recruited over the past few years and represent a prevalence series, for which an appropriate comparison group for the cases is difficult to identify and recruit. In a case-only study, only cases are used to investigate the multiplicative effects of the exposures and susceptible genotypes of interest, while non-case subjects (traditionally controls) are solely used to test the independence between the exposure and the susceptible genotype. Therefore, this approach avoids the challenges of control selection, a major limitation inherent in the case-control approach. This thesis comprised of three independent studies: the first study investigated the interactions between genetic polymorphisms of GSTM1, P1, T1 and Z1 and smoking in PD; the second study examined the interactions between genetic polymorphisms of CYP2E1 and smoking in PD; and the third study examined the interactions between genetic polymorphisms of CYP2D6 and smoking in PD. The first two studies recruited 400 white Caucasian PD cases from both hospital wards and private neurology clinics (230 men and 170 women). The third study further included 142 white Caucasian PD cases newly recruited from the same sources (542 in total, 321 men, and 221 women). The mean age of cases was 67 years with the average onset age at 60 years. GSTM1, GSTP1, GSTT1, GSTZ1 AND CYP2E1 genotyping processes were performed using protocols previously published with minor modification, whereas CYP2D6 genotyping methods were mainly developed by me with assistance from associate supervisor Dr. George Mellick. Reliability and validity of the PCR and RFLP methods were assessed through re-conducting the genotype assays using at least a 10% sample of our DNA samples. The results for all re-assessments were 100% concordant. Crude bivariate analyses were adjusted for potential confounding effects of the variables, including age at onset, gender, family history of PD and pesticide exposures. Among our unaffected, aged subjects (mean age: 63.9 years, sd: 11.4 years), the genotype frequencies at each locus were similar to those reported in other Caucasian populations. The first study showed that the proportion of carriers of the GSTP1-114Val allele (mutant) increased with increasing smoking dose from 0 to > 30 pack-years. Homozygotes of the 114Ala allele (wild-type) decreased with increasing smoking dose (trend test: p=0.02). This trend existed both in male and female cases. This dose-effect relationship was most significant in the group of cases with late-onset PD (i.e., age at onset > 55 years) with the ORicase-only values of 1.88 (95%CI: 0.65-5.48) and 2.63 (95%CI: 1.07-6.49) for > 0-10 and > 10 pack-years, respectively. No similar trend was found among our unaffected, aged subjects (p=0.42). Haplotype analyses revealed significant differences for GSTP1 haplotypes between smoking and non-smoking PD cases (ORicase-only for *C haplotype=2.00 (95%CI: 1.11-3.60), p=0.03). In this case, smoking-exposed PD cases were more likely to posses the *C haplotype defined by A to G base-pair transition at nucleotide +313 and C to T base-pair transition at nucleotide +341 (at amino acid level, valine at both positions 105 and 114). The second study found no difference in CYP2E1 genotype frequencies between PD cases who ever smoked compared to those who never smoked (odds ratio for interaction (ORi) = 1.00 (95% CI: 0.39-2.51, p=0.99)). No CYP2E1 gene-smoking interactions were detected in relation to age at onset of PD. The third study found that among cases without regular pesticide exposures, CYP2D6 PMs who smoked more than 5 pack-years had a later mean age at disease onset (68.6 years) than those with extensive metaboliser phenotypes (EMs) (61.1 years, p=0.02) and non-smokers (60.5 years, p=0.01). Analysis of aged subjects without PD confirmed that neither smoking status nor CYP2D6 PM status was associated with age itself. Our data suggest: 1. smoking exposure is independent of GSTM1, P1, T1, Z1 and CYP2E1 genotypes; 2. smoking may be, to some extent, associated with CYP2D6 genotypes; 3. there are no multiplicative interactive effects linking smoking and GSTM1, T1, Z1 or CYP2E1 genotypes with the risk for PD; 4. there is a multiplicative interactive effect between smoking and GSTP1 haplotype - particularly for genotypes carrying the 114Val allele; and 5. there is a multiplicative interactive effect between smoking and CYP2D6 PMs - particularly for people who ever smoked cigarettes more than 5 pack-years. In general, this thesis provides a model for exploring the gene-smoking interactions in PD. Further studies need to consider the recruitment of a large number of population-based and randomly-selected samples and to pay more attention to measurement of environmental exposures. Further studies also need to examine simultaneously the impact of smoking, pesticide exposures and other potential risk factors on PD. These studies will build evidence for interactions contributing to this common neurological movement disorder.
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Estresse oxidativo em pacientes beta talassêmicos heterozigotos e com deficiência de glicose-6-fosfato desidrogenaseOndei, Luciana de Souza [UNESP] 28 August 2009 (has links) (PDF)
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000603676.pdf: 889558 bytes, checksum: df390d92da0411515e31635f99e1d76d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Ministério da Saúde / Na talassemia beta, o acúmulo das cadeias alfa livres, bem como a liberação do grupo heme e do ferro durante o processo hemolítico, ocasionam aumento de danos oxidativos que podem resultar em lipoperoxidação de membranas celulares, desnaturação de proteínas e oxidação da hemoglobina. Na deficiência de glicose- 6-fosfato desidrogenase (G6PD), esse aumento é decorrente da diminuição da produção de nicotinamida adenina dinucleotídeo fosfato reduzido (NADPH) que pode resultar em hemólise intravascular. Diante da possibilidade de estresse oxidativo nos portadores de beta talassemia heterozigota e nos indivíduos com deficiência de G6PD, neste trabalho avaliou-se a expressão fenotípica das afecções genéticas por meio da identificação das mutações e análise de marcadores para estresse oxidativo. Para o estabelecimento dos grupos controle e com deficiência de G6PD foram avaliadas 544 amostras de sangue periférico de indivíduos da região Noroeste do Estado de São Paulo, sendo 426 doadores de sangue e 118 indivíduos de uma instituição de ensino superior. Para a composição do grupo com talassemia beta heterozigota foram avaliadas 46 amostras de sangue de indivíduos com diagnóstico clínico de talassemia beta da cidade de São Carlos/SP. Foram realizados métodos de triagem e confirmatórios para a identificação da talassemia beta heterozigota e da deficiência de G6PD, e dosagens bioquímicas para quantificação das espécies reativas ao ácido tiobarbitúrico (TBARS), utilizado como marcador de estresse oxidativo, e para a determinação da capacidade antioxidante em equivalência ao Trolox (TEAC). Os polimorfismos da glutationa S-transferase (GST) GSTM1 e GSTT1 foram avaliados por PCR multiplex o de GSTP1 por PCR/RFLP. No grupo com talassemia beta heterozigota foram encontradas 18 (39%) amostras com a mutação CD39; 22 (48%) com a mutação... / In beta thalassemia, the excess of unpaired alpha chains, as well as the heme group and iron released during the hemolytic process increase the oxidative damage. In G6PD deficiency, this increase is caused by a reduced production of NADPH that results in an intravascular hemolysis. Thus, facing the oxidative stress possibility in beta thalassemia carriers and G6PD deficiency individuals, it was aimed to evaluate the fenotypic expression of this genetic disorders through the mutation identification, as well as the oxidative stress marker analysis. We used 544 peripheral blood samples of individuals from São Paulo’s northwestern to control group and to G6PD deficiency group establishment. For beta thalassemia heterozygote group were evaluated 48 blood samples of São Carlos/SP city. Tests were carried out aiming the screening and confirmation of beta thalassemia and G6PD deficiency, as well as the analysis of lipid peroxidation products measured as thiobarbituric acid reactive species (TBARS) and Trolox equivalent antioxidant capacity (TEAC). Were determined the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms. The analysis with beta thalassemia carriers allowed to establish in the study group a frequency of 39% for CD39 mutation, 48% for IVS-I-110 mutation and 2% for IVS-I-6 mutation. For G6PD deficiency was founded a frequency of 3.86%. The beta thalassemic group evaluation showed an increase of TBARS and TEAC values, when compared to the control group. There was a tendency to increase lipid peroxidation in beta0 CD39 mutants compared to beta+ IVS-I-110 mutants, because there is more free chains amount in beta0 thalassemia than beta+ thalassemia. In the G6PD deficiency analysis was found a lower G6PD activity in men than in women, but there was no interference of gender in the TBARS and TEAC assays results. The comparison between the control group and the G6PD deficiency group... (Complete abstract click electronic access below)
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The role of glutathione S-transferase Pi (GSTPi) in asthmaSchroer, Kathy T. 13 April 2010 (has links)
No description available.
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Determinação do polimorfismo da enzima GSTP1 em trabalhadores expostos à sílica e associação com silicose / Determination of enzyme GSTP1 polymorphism in workers exposed to silica and association with silicosisRocha, Daniele Ramos January 2010 (has links)
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Previous issue date: 2010 / A sílica é um composto natural formado pelos dois elementos mais abundantes na Terra - oxigênio e silício. A exposição a partículas de sílica cristalina induz a uma inflamação pulmonar crônica, que pode evoluir para fibrose pulmonar, acarretando na doença conhecida como silicose. O estresse oxidativo desempenha um papel importante na patogênese desta fibrose pulmonar. Sendo assim, a expressão de genes antioxidantes, como glutationa S-transferases (GSTs), são importantes componentes de proteção das células contra o estresse oxidativo e são conhecidas como genes altamente polimórficos, podendo contribuir para a susceptibilidade a silicose. O polimorfismo da GSTP1 A/G resulta na substituição do aminoácido isoleucina por valina, diminuindo, substancialmente, a atividade da enzima GSTP1. O estudo teve como objetivo a determinação do polimorfismo da enzima GSTP1 em trabalhadores expostos à sílica e associação com silicose. A população foi composta por 82 trabalhadores expostos à sílica oriundos, principalmente, da indústria naval. O polimorfismo da GSTP1 foi analisado por PCR-RFLP. Como resultado verificou-se que 31,6 por cento dos trabalhadores tinham genótipo A/A, 57,9 por cento A/G e 10,5 por cento G/G. Observou-se que a média da atividade enzimática da GST foi menor (1,58 U/mL enzima) em indivíduos com o alelo G em relação ao alelo A (1,84 U/mL de enzima). Trabalhadores expostos à sílica portadores do alelo G mostraram um maior risco de desenvolver silicose, embora os resultados não tenham sido significativos, provavelmente, em função do universo amostral. Os indivíduos portadores do alelo G tiveram níveis menores na atividade da GST, independente do genótipo das enzimas GSTM1 e GSTT1. Em conclusão, estudos adicionais devem ser realizados para determinar o polimorfismo da GSTP1 em populações expostas à sílica em comparação com populações não-expostas, pois os resultados deste trabalho sugerem a utilização da determinação do polimorfismo da GSTP1, no processo de avaliação da exposição à sílica, como uma ferramenta complementar na identificação de subgrupos mais susceptíveis ao desenvolvimento da doença silicose. / Sílica is the natural compound of the two most abundant elements on Earth - oxygen and silicon.
Exposure to crystalline silica particles induces chronic lung inflammation, which may progress to
lung fibrosis, a disease known as silicosis. The oxidative stress plays an important role in the
pathogenesis of pulmonary fibrosis. In this respect, the expression of antioxidant genes such as
glutathione S-transferases (GSTs) are important to protect cells from oxidative stress and they are
known as highly polymorphic genes, that may contribute to silicosis susceptibility. The GSTP1
A G polymorphism results in amino acid substitution isoleucine for valine which substantially
diminishes GSTP1 enzyme activity. The objetive of study was the determination of enzyme
GSTP1 polymorphism in workers exposed to silica and association with silicosis. The population
was composed of 82 workers exposed to silica coming mainly from the shipbuilding
industry.GSTP1 polymorphism was analyzed by PCR-RFLP. As a result it was found that 31,6%
of workers had genotype A/A, 57,9% A/G and 10.5% G/G. It was observed that the mean
enzyme activity of GST was lower (1.58 U / mL enzyme) in individuals with allele G compared
with allele A (1.84 U / mL enzyme). Workers exposed to silica with allele G showed a higher risk
of developing silicosis, although the results had not been significant, probably because of sample
size. Individuals with allele G had lower levels of GST activity, independent of the genotype of
GSTM1 and GSTT1 enzymes. In conclusion, further studies to determine the polymorphism of
GSTP1 should be conducted in populations exposed to silica compared with non-exposed
populations, because the results in this paper suggest the use of the determination of the
polymorphism of GSTP1, in the process of evaluating the exposure to silica, as a complementary
tool in the identification of subgroups more likely to develop the disease silicosis. / Sílica is the natural compound of the two most abundant elements on Earth - oxygen and silicon.
Exposure to crystalline silica particles induces chronic lung inflammation, which may progress to
lung fibrosis, a disease known as silicosis. The oxidative stress plays an important role in the
pathogenesis of pulmonary fibrosis. In this respect, the expression of antioxidant genes such as glutathione S-transferases (GSTs) are important to protect cells from oxidative stress and they are known as highly polymorphic genes, that may contribute to silicosis susceptibility. The GSTP1 A G polymorphism results in amino acid substitution isoleucine for valine which substantially diminishes GSTP1 enzyme activity. The objetive of study was the determination of enzyme GSTP1 polymorphism in workers exposed to silica and association with silicosis. The population was composed of 82 workers exposed to silica coming mainly from the shipbuilding
industry.GSTP1 polymorphism was analyzed by PCR-RFLP. As a result it was found that 31,6%
of workers had genotype A/A, 57,9% A/G and 10.5% G/G. It was observed that the mean enzyme activity of GST was lower (1.58 U / mL enzyme) in individuals with allele G compared with allele A (1.84 U / mL enzyme). Workers exposed to silica with allele G showed a higher risk of developing silicosis, although the results had not been significant, probably because of sample size. Individuals with allele G had lower levels of GST activity, independent of the genotype of GSTM1 and GSTT1 enzymes. In conclusion, further studies to determine the polymorphism of GSTP1 should be conducted in populations exposed to silica compared with non-exposed populations, because the results in this paper suggest the use of the determination of the polymorphism of GSTP1, in the process of evaluating the exposure to silica, as a complementary tool in the identification of subgroups more likely to develop the disease silicosis.
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Association Of The Cyp2e1, Fmo3, Nqo1, Gst And Nos3 Genetic Polymorphisms With Ischemic Stroke Risk In Turkish PopulationOzcelik, Aysun 01 December 2011 (has links) (PDF)
Stroke, a major cause of death and disability, is described as interruption or severe reduction of blood flow in cerebral arteries. Oxidative stress plays an important role in the pathogenesis of atherosclerosis and carotid atherosclerosis is a risk factor for stroke. Combination of multiple environmental and genetic risk factors is thought to increase susceptibility to the development of this disease. Therefore, investigation of the polymorphisms of drug metabolizing enzymes is of crucial
importance to determine the molecular etiology of the disease. The main objective of this study was to investigate the possible association between polymorphisms of enzymes causing oxidative stress (CYP2E1, FMO3 and NOS3) and enzymes protecting against oxidative stress (GST and NQO1), and the pathogenesis of atherosclerosis and ischemic stroke risk.
The study population consisted of 245 unrelated ischemic stroke patients and 145 healthy control subjects. There was no statistically difference between the patient and control groups in terms of age and gender. Hypertension, diabetes,
smoking and obesity were found to be at least 2 times more common in stroke patients than controls. While total cholesterol, triglyceride and LDL-cholesterol level were higher in stroke patients, HDL-cholesterol level was lower in stroke patients when compared to controls.
In the case-control analyses for the risk of ischemic stroke, CYP2E1*5B mutant allele, *5B was found to be associated with the development of disease (Odds Ratio / OR=7.876, 95%CI=1.025-60.525, P=0.019). In addition, significant difference was
observed between stroke patients and controls with respect to CYP2E1*5B genotype distribution (OR=0.869, 95%CI=1.044-62.339, P=0.017). On the other hand, in the NQO1*2 polymorphism, together with NQO1 heterozygote (*1*2), NQO1 homozygote mutant (*2*2) genotype was found protective against ischemic stroke (OR=0.627, 95%CI=0.414-0.950, P=0.027). The risk of hypertensive individuals having stroke was highest in the FMO3 472GA group (OR=6.110, P=0.000). In diabetics, GSTP1 313AG genotype was found to be the highest risk factor for stroke (OR=3.808 P=0.001). On the other hand, NQO1 *1*2 heterozygote genotype was
associated with 5 times increased risk for stroke in smokers (OR=5.000, P=0.000). In addition GSTM1 present genotype constituted 8 times increased stroke risk in obese
individuals (OR=8.068, P=0.001). Logistic regression analysis revealed that hypertension, diabetes mellitus, obesity and smoking were significant risk factors for stroke. On the other hand, HDL-cholesterol and having NQO1 *1*2 heterozygote
genotype were found to be protective factors against stroke.
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Estresse oxidativo em pacientes beta talassêmicos heterozigotos e com deficiência de glicose-6-fosfato desidrogenase /Ondei, Luciana de Souza. January 2009 (has links)
Orientador: Claudia Regina Bonini Domingos / Banca: Antonio Fabron Junior / Banca: Luiz Carlos de Mattos / Banca: Sonia Maria Oliani / Banca: Wilson Araújo Silva Junior / Resumo: Na talassemia beta, o acúmulo das cadeias alfa livres, bem como a liberação do grupo heme e do ferro durante o processo hemolítico, ocasionam aumento de danos oxidativos que podem resultar em lipoperoxidação de membranas celulares, desnaturação de proteínas e oxidação da hemoglobina. Na deficiência de glicose- 6-fosfato desidrogenase (G6PD), esse aumento é decorrente da diminuição da produção de nicotinamida adenina dinucleotídeo fosfato reduzido (NADPH) que pode resultar em hemólise intravascular. Diante da possibilidade de estresse oxidativo nos portadores de beta talassemia heterozigota e nos indivíduos com deficiência de G6PD, neste trabalho avaliou-se a expressão fenotípica das afecções genéticas por meio da identificação das mutações e análise de marcadores para estresse oxidativo. Para o estabelecimento dos grupos controle e com deficiência de G6PD foram avaliadas 544 amostras de sangue periférico de indivíduos da região Noroeste do Estado de São Paulo, sendo 426 doadores de sangue e 118 indivíduos de uma instituição de ensino superior. Para a composição do grupo com talassemia beta heterozigota foram avaliadas 46 amostras de sangue de indivíduos com diagnóstico clínico de talassemia beta da cidade de São Carlos/SP. Foram realizados métodos de triagem e confirmatórios para a identificação da talassemia beta heterozigota e da deficiência de G6PD, e dosagens bioquímicas para quantificação das espécies reativas ao ácido tiobarbitúrico (TBARS), utilizado como marcador de estresse oxidativo, e para a determinação da capacidade antioxidante em equivalência ao Trolox (TEAC). Os polimorfismos da glutationa S-transferase (GST) GSTM1 e GSTT1 foram avaliados por PCR multiplex o de GSTP1 por PCR/RFLP. No grupo com talassemia beta heterozigota foram encontradas 18 (39%) amostras com a mutação CD39; 22 (48%) com a mutação... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In beta thalassemia, the excess of unpaired alpha chains, as well as the heme group and iron released during the hemolytic process increase the oxidative damage. In G6PD deficiency, this increase is caused by a reduced production of NADPH that results in an intravascular hemolysis. Thus, facing the oxidative stress possibility in beta thalassemia carriers and G6PD deficiency individuals, it was aimed to evaluate the fenotypic expression of this genetic disorders through the mutation identification, as well as the oxidative stress marker analysis. We used 544 peripheral blood samples of individuals from São Paulo's northwestern to control group and to G6PD deficiency group establishment. For beta thalassemia heterozygote group were evaluated 48 blood samples of São Carlos/SP city. Tests were carried out aiming the screening and confirmation of beta thalassemia and G6PD deficiency, as well as the analysis of lipid peroxidation products measured as thiobarbituric acid reactive species (TBARS) and Trolox equivalent antioxidant capacity (TEAC). Were determined the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms. The analysis with beta thalassemia carriers allowed to establish in the study group a frequency of 39% for CD39 mutation, 48% for IVS-I-110 mutation and 2% for IVS-I-6 mutation. For G6PD deficiency was founded a frequency of 3.86%. The beta thalassemic group evaluation showed an increase of TBARS and TEAC values, when compared to the control group. There was a tendency to increase lipid peroxidation in beta0 CD39 mutants compared to beta+ IVS-I-110 mutants, because there is more free chains amount in beta0 thalassemia than beta+ thalassemia. In the G6PD deficiency analysis was found a lower G6PD activity in men than in women, but there was no interference of gender in the TBARS and TEAC assays results. The comparison between the control group and the G6PD deficiency group... (Complete abstract click electronic access below) / Doutor
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Oxidativer Stress als Biomarker für die (Neben-) Wirkungen von Strahlentherapie: Bestimmung von Isoprostanspiegeln und Genexpressionsprofilen in Patientenproben / Oxidative stress as a marker for effects and side effects of radiotherapy. Analysis of isoprostane levels and gene expression profiles in patients samplesKluge, Friedrich 29 November 2011 (has links)
No description available.
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