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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.
141

Fatores de risco associados à infecção pelo Helicobacter pylori e ao desfecho clínico / Risk factors associated with Helicobacter pylori infection and to the clinical outcome

Ramis, Ivy Bastos 21 November 2014 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-08-29T13:17:11Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_ivy_bastos_ramis.pdf: 1360974 bytes, checksum: 5f055cbf4d5ce0a95672ccdf092907c8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-08-29T19:50:35Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_ivy_bastos_ramis.pdf: 1360974 bytes, checksum: 5f055cbf4d5ce0a95672ccdf092907c8 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-08-29T19:50:44Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_ivy_bastos_ramis.pdf: 1360974 bytes, checksum: 5f055cbf4d5ce0a95672ccdf092907c8 (MD5) / Made available in DSpace on 2017-08-29T19:50:52Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_ivy_bastos_ramis.pdf: 1360974 bytes, checksum: 5f055cbf4d5ce0a95672ccdf092907c8 (MD5) Previous issue date: 2014-11-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Helicobacter pylori é uma bactéria que infecta a mucosa gástrica de aproximadamente 50% da população humana mundial. A infecção por H. pylori tem sido associada a uma variedade de doenças, tais como gastrite, doença ulcerosa péptica e carcinoma gástrico. Acredita-se que a combinação de variáveis ambientais/comportamentais, fatores genéticos do hospedeiro e genes de patogenicidade bacteriana possa interferir na gravidade da lesão gástrica e no desfecho clínico de infecção por H. pylori. Desta forma, o presente trabalho objetivou determinar a frequência e potenciais fatores de risco da infecção por H. pylori, assim como identificar os polimorfismos nos genes da interleucina (IL)-1, IL-6, IL-8 e IL-10 e suas associações com infecção por H. pylori, com cytotoxin associated gene A (gene cagA) de H. pylori e com patologias gástricas. Para isso, foi conduzido um estudo transversal, incluindo amostras de biópsia gástrica de 227 pacientes, submetidos à endoscopia digestiva alta. Um questionário foi aplicado aos pacientes antes da endoscopia. O diagnóstico de H. pylori baseou-se na histologia e na polymerase chain reaction (PCR). O gene cagA foi identificado por PCR. Os polimorfismos nos genes da IL-1B (nas posições -511, -31 e +3954), IL-6 (na posição -174), IL-8 (na posição -251) e IL-10 (nas posições -819 e -592) foram detectados por PCR-restriction fragment length polymorphism (RFLP). A análise do polimorfismo variable number of tandem repeat (VNTR) no gene IL-1RN foi realizada por PCR, seguida por eletroforese em gel de agarose. Dos 227 pacientes incluídos neste estudo, 151 foram positivos para H. pylori e 76 negativos. Com base nos questionários aplicados aos pacientes, verificou-se existir associação significativa entre a presença de H. pylori e a aglomeração familiar, a idade, e os diagnósticos endoscópicos e histológicos. Quanto aos fatores genéticos do hospedeiro observou-se que os polimorfismos nas regiões promotoras dos genes IL-1B e IL-8 estavam significativamente relacionados à infecção por H. pylori. As cepas de pacientes H. pylori positivos portadores do gene cagA foram significativamente associadas com o polimorfismo da IL-1B na posição -511. Adicionalmente, na presença da infecção pelo H. pylori, demonstrou-se que os polimorfismos na região promotora do gene IL-1B estiveram correlacionados com um risco aumentado de gastrite, enquanto aqueles nos genes da IL-8 e da IL-10 foram associados a um risco elevado da doença ulcerosa péptica. Conclui-se que, provavelmente, os polimorfismos genéticos do hospedeiro exerçam influência sobre o curso e a gravidade das doenças gástricas. Espera-se que os resultados deste trabalho possam contribuir, em breve, tanto para a prevenção dessas desordens quanto para uma terapia mais adequada e eficiente, isto porque o conhecimento das bases moleculares do hospedeiro e do microrganismo viabiliza o desenvolvimento de testes moleculares, os quais poderão ser aplicados em prol de um correto prognóstico das patologias gástricas. / Helicobacter pylori is a bacterium that infects the gastric mucosa of approximately 50% of the world´s human population. H. pylori infection has been associated with a variety of diseases such as gastritis, peptic ulcer disease and gastric carcinoma. It is believed that the combination of environmental/behavioral variables, host genetic factors and bacterial pathogenicity genes can interfere in the severity of gastric damage and in the clinical outcome of H. pylori infection. In this sense, the present study aimed to determine the frequency and potential risk factors of the H. pylori infection, even as identify polymorphisms in the interleukin (IL)-1, IL-6, IL-8 and IL-10 genes and their associations with H. pylori infection, with cagA gene of H. pylori, and with gastric pathologies. For this, it was conducted a cross-sectional study, including gastric biopsy samples from 227 patients, submitted to upper gastrointestinal endoscopy. A questionnaire was applied to the patients before endoscopy. The diagnosis of H. pylori was based in histology and in polymerase chain reaction (PCR). The cagA gene was identified by PCR. The polymorphisms in the genes of IL-1B (at positions -511, -31 and +3954), IL-6 (at position -174), IL-8 (at position -251) and IL-10 (at positions -819 and -592) were detected by PCR-restriction fragment length polymorphism (PCR-RFLP). The analysis of the variable number of tandem repeat (VNTR) polymorphism in the IL-1RN gene was performed by PCR followed by electrophoresis agarose gel. Of the 227 patients included in this study, 151 were positive for H. pylori and 76 negative. Based on the questionnaires applied to the patients, it was found a significant association between the presence of H. pylori and the household crowding, the age, and the diagnoses histological and endoscopic. As for host genetic factors was observed that polymorphisms in the promoter region of the IL-1B and IL-8 genes were significantly related with H. pylori infection. The strains from patients H. pylori positive carrying the cagA gene were significantly associated with the polymorphism of IL-1B at position -511. Additionally, in the presence of H. pylori infection, it was demonstrated that polymorphisms in the promoter region of the IL-1B gene were correlated with an enhanced risk of gastritis, while those in the IL-8 and IL-10 genes were associated with higher risk of peptic ulcer disease. We conclude that probably, the host genetic polymorphisms exert influence in the course and gravity of gastric diseases. It is hoped that the results of this work may contribute soon, to the prevention of these diseases and for a more appropriate and effective therapy, this because the knowledge of the molecular basis of the host and the microorganism enables the development of molecular tests that may to be applied toward a correct prognosis of gastric pathologies.
142

Polimorfismo antigênico e reconhecimento de regiões variáveis da proteína 1 de superfície de merozoíto de Plasmodium vivax (PvMSP-1) por anticorpos naturalmente adquiridos na Amazônia Ocidental Brasileira / Antigenic polymorphism and recognition of variable domains of merozoite surface protein 1 of Plasmodium vivax (PvMSP-1) by naturally acquired antibodies of subjects from Brazilian Western Amazonia

Melissa da Silva Bastos 11 October 2007 (has links)
A MSP-1 de Plasmodium vivax (PvMSP-1), o principal alvo para o desenvolvimento de uma vacina contra a malária, é constituída por seis domínios altamente polimórficos flanqueados por seqüências conservadas. Apesar de evidências de que a divergência na seqüência da PvMSP-1 é está sendo mantida por mais de cinco milhões de anos por seleção balanceada exercida pela imunidade adquirida pelo hospedeiro, a especificidade dos anticorpos adquiridos naturalmente contra a PvMSP-1 ainda é pouco estudada. Este trabalho mostra que 15 proteínas recombinantes que correspondem às variantes da PvMSP-1 comumente encontradas em parasitos locais foram pouco reconhecidas por 376 indivíduos não-infectados com idade entre 5 e 90 anos expostos à malária na Amazônia rural; menos de 30% dos indivíduos tiveram anticorpos IgG detectáveis contra no mínimo uma variante dos blocos 2, 6 e 10 que foram expressas, embora 54,3% reconheceram o domínio conservado C-terminal PvMSP-119. Apesar da proporção de respondedores às variantes da PvMSP-1 ter aumentado substancialmente durante infecções agudas subseqüentes por P. vivax, os anticorpos não foram necessariamente específicos para as variantes da PvMSP-1 encontradas nos parasitos infectantes. São discutidos a contribuição relativa do polimorfismo antigênico, a fraca imunogenicidade e o pecado antigênico original (a tendência de a exposição a uma nova variante antigênica induzir resposta de anticorpos com especificidade pré-existente) para os padrões observados de reconhecimento por anticorpos da PvMSP-1. É sugerido que a resposta de anticorpos ao repertório de domínios variáveis da PvMSP-1 em indivíduos continuamente expostos é induzida somente após algumas infecções repetidas e requerem re-estímulo freqüente, com claras implicações para o desenvolvimento de subunidades de vacinas baseadas na PvMSP-1. / The merozoite surface protein 1 of Plasmodium vivax (PvMSP-1), a major target for malaria vaccine development, contains six highly polymorphic domains interspersed with conserved sequences. Although there is evidence that the sequence divergence in PvMSP-1 has been maintained over five million years by balanced selection exerted by host?s acquired immunity, the variant-specificity of naturally acquired antibodies to PvMSP-1 remains little investigated. Here we show that 15 recombinant proteins corresponding to PvMSP-1 variants commonly found in local parasites were poorly recognized by 376 noninfected subjects aged 5-90 years exposed to malaria in rural Amazonia; less than onethird of them had detectable IgG antibodies to at least one variant of blocks 2, 6 and 10 that were expressed, although 54.3% recognized the invariant C-terminal domain PvMSP-119. Although the proportion of responders to PvMSP-1 variants increased substantially during subsequent acute P. vivax infections, the specificity of IgG antibodies did not necessarily match the PvMSP-1 variant(s) found in infecting parasites. We discuss the relative contribution of antigenic polymorphism, poor immunogenicity, and original antigenic sin (the skew in the specificity of antibodies elicited by exposure to new antigenic variants due to preexisting variant-specific responses) to the observed patterns of antibody recognition of PvMSP-1. We suggest that antibody responses to the repertoire of variable domains of PvMSP-1 to which subjects are continuously exposed are only elicited after several repeated infections and may require frequent boosting, with clear implications for the development of PvMSP-1-based subunit vaccines.
143

Análise de polimorfismos do gene que codifica a proteína B do surfactante: comparação entre recém-nascidos pré-termo com e sem síndrome do desconforto respiratório / Surfactant protein B gene polymorphisms analysis: comparison between preterm newborns with and without respiratory distress syndrome

Priscila Pinheiro Ribeiro Lyra 01 July 2010 (has links)
A síndrome do desconforto respiratório (SDR) é causada pela deficiência transitória de surfactante pulmonar em recém-nascidos (RN) prematuros nos primeiros dias de vida. Estudos sugerem que a etiologia da SDR seja multifatorial e multigênica. A proteína B do surfactante (SP-B) é fundamental para o metabolismo do surfactante e para uma função pulmonar normal. A presença de polimorfismos e mutações em genes dos componentes do surfactante, particularmente no gene da SP-B, parece estar associada à SDR. Objetivos: Determinar a freqüência de polimorfismos do gene que codifica a proteína B do surfactante no DNA de recém nascidos pré-termo com e sem SDR, comparar as freqüências desses polimorfismos entre os dois grupos e avaliar se existe alguma relação entre sexo, raça e SDR. Casuística e Métodos: Foram incluídos no estudo 151 RNPT, sendo 79 sem SDR com idades gestacionais variando entre 29 semanas e 35 semanas e 6 dias e 72 RN pré-termo com SDR com idades gestacionais variando de 26 a 35 semanas. Foram analisados quatro polimorfismos: A/C no nucleotídeo - 18; C/T no nucleotídeo 1580; A/G no nucleotídeo 9306 e G/C no nucleotídeo 8714. Os polimorfismos foram determinados através da amplificação dos segmentos de DNA genômico por reação em cadeia da polimerase e posterior genotipagem. Os genótipos foram definidos através da análise dos produtos obtidos a partir de reações com enzimas de restrição [PCR-based converted restriction fragment length polymorphism (cRFLP)]. Resultados: O grupo Controle foi constituído por 79 RN pré-termo sem SDR; sendo 42 (53,2%) do sexo feminino e 37 (46,8%) do sexo masculino; 34 (43%) da raça negra, 16(20,3%) da raça branca e 29(36,7) de indivíduos pardos. O peso variou de 1170g a 3260 , e a idade gestacional variou de 29 semanas a 35 semanas e seis dias (média de 33 semanas e 6 dias).O grupo SDR foi composto por 72 RNPT, sendo que 31 (43%) do sexo feminino e 41 (57%) do sexo masculino; 31(43%) da raça negra, 16 (14%) da raça branca e 31(43%) de indivíduos pardos. O peso variou de 614g a 2.410g ; a idade gestacional média foi de 32 semanas , tendo variado de 26 semanas a 35 semanas. O modelo de regressão logística múltipla, utilizado para avaliar a contribuição das diversas variáveis na probabilidade de ocorrer SDR, demonstrou que a idade gestacional foi a variável que mais contribuiu para a ocorrência da patologia, e que o genótipo AG do polimorfismo A/G na posição 9306 foi um fator protetor para a doença nesta população (OR 0.1681; IC 95% 0.0426 - 0.6629). Não foram observadas diferenças entre as freqüências dos demais polimorfismos avaliados entre os 2 grupos de recém-nascidos, bem como diferenças quanto à raça e sexo. Conclusões: A presença do genótipo AG do polimorfismo A/G na posição 9306 do gene que codifica a proteína B do surfactante foi fator protetor para o desenvolvimento da síndrome do desconforto respiratório em recém-nascidos da cidade de Salvador-Bahia. Os polimorfismos A/C no nucleotídeo - 18, C/T no nucleotídeo 1580, e G/C no nucleotídeo 8714 presentes no referido gene não estiveram associados à síndrome do desconforto respiratório em recém-nascidos na amostra estudada. / The respiratory distress syndrome (RDS) is caused by surfactant transient deficiency in preterm babies soon after birht. Studies sugest that RDS etiology is multifactorial and multigenic. Surfactant protein B (SP-B) is essential for surfactant metabolism and fornormal lung function. Polymorphisms and mutations in the genes that encode the surfactant components, particularly the SP-B gene, have been associated to the pathogenesis of RDS. Aims: To analyze SP-B gene polimorfisms frequencies in preterm babies with RDS and healthy term newborns, to compare the polymorphisms frequencies between both groups and to evaluate if there are differences related to sex, race and RDS. Material and Methods: We included 151 neonates, 79 preterm babies without RDS and gestational ages ranging from 26 weeks to 35 weeks , and 72 preterm newborns with RDS, gestational ages ranging from 29 weeks to 35 weeks and 6 days. Four SP-B gene polymorphisms were analyzed: A/C at - 18, C/T at 1580; A/G at 9306 and G/C at nucleotide 8714. The polymorphisms were detected by PCR amplification of genomic DNA and genotyping. The genotypes were determined using PCR-based converted restriction fragment length polymorphism (cRFLP). Results: The control group comprised 79 preterm babies without RDS; 42(53,2%) were female and 37(46,8%) male; 34(43%) were black, 16(20,3) were Whites and 29(36.7%) non- Whites/non black. Weight ranged from 1.170g to 3.260g ; gestational age ranged from 29 weeks to 35 weeks and six days (mean 33 weeks and 6 days). The RDS group comprised 72 preterm neonates, 31(43%) female and 41(57%) male; 31(43%) were black, 16(14%) were Whites and 31(43%) non-Whites/non black. Weight ranged from 614g to 2.410g ; mean gestational age was 32 weeks (range, 26-35 weeks). The logistic regression model showed that gestational age was the variable that most contributed to the ocurrence of the respiratory distress syndrome and the AG genotype of the polymorphism A/G at 9306 was a protector factor for the disease in the studied population (OR 0.1681; CI 95% 0.0426 - 0.6629). We did not detect differences between the frequencies of the other evaluated polymorphisms between both groups of newborns. Conclusions: The presence of AG genotype at 9306 of the surfactant protein B (SP-B) gene was a protector factor for the development of the respiratory distress syndrome in newborns from the city of Salvador-Bahia. The polymorphisms A/C at nucleotide - 18, C/T at 1580, and G/C at nucleotide 8714 from the SP-B gene were not associated with respiratory distress syndrome in the studied population.
144

Prevalência de polimorfismos da enzima CYP2D6 em pacientes em terapia com psicotrópicos / Prevalence of CYP2D6 enzyme polymorphisms in patients on psychotropic therapy

FERNANDES, Mauricio Avelar 28 April 2017 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-09-13T17:47:07Z No. of bitstreams: 1 MauricioFernandes.pdf: 1547228 bytes, checksum: 87d9e63be597d8eaf8f7a783479e1294 (MD5) / Made available in DSpace on 2017-09-13T17:47:07Z (GMT). No. of bitstreams: 1 MauricioFernandes.pdf: 1547228 bytes, checksum: 87d9e63be597d8eaf8f7a783479e1294 (MD5) Previous issue date: 2017-04-28 / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão / INTRODUCTION: In Brazil, it is reported that a great part of the patients who arrive for the primary care service have as main complaint: sadness (depression) and / or anxiety, also with more complex disorders such as problems related to abuse of alcohol and serious and persistent mental disorders, such as schizophrenia and affective psychoses (bipolar mood disorder). In the pharmacogenetic studies of antidepressants and antipsychotics, cytochrome P450 (CYPs) enzymes have been shown to be one of the most significant targets in the interindividual changes in drug response kinetic parameters. OBJECTIVE: To characterize the frequency of CYP2D6 polymorphisms (*4, *6 and *17) in users of psychotropic therapy, especially tricyclic antidepressants and antipsychotics. METHODS: Cross - sectional, descriptive study carried out in the city of São Luis – MA. RESULTS: From a total of 105 charts, a sample of 43 patients was collected. The mean age was 40.98 (± 11.04) years, of which 24 (55.81%) were male and 19 (44, 19%) of females. Regarding the pharmacotherapy, all participants (100%) were on daily use of the antipsychotic haloperidol, seventeen (39.53%) patients used risperidone and one (2.32%) patient used amitriptyline (tricyclic antidepressant), all three drugs are substrates of the enzyme CYP2D6. For the polymorphism of CYP2D6, we had a prevalence of 11 (25.48%) for allele 4, and all the patients presented with this polymorphism were heterozygous, that means they had one polymorphic allele and one normal allele. For allele 17, we had a prevalence of 4 (9.3%), also all patients being heterozygous for this allele. Allele 6 did not appear in any patient in our study. We also had two patients who presented the polymorphisms for alleles * 4 and * 17 at the same time. CONCLUSION: This study was able to characterize the frequency of CYP2D6 (* 4, * 6 and 17 *) polymorphisms in users of psychotropic therapy, including tricyclic antidepressants and antipsychotics, in addition to contributing to a higher dose / response do medication, ensuring greater safety and efficacy in the use of medicines, improving the quality of life of patients. / INTRODUÇÃO: No Brasil, tem-se o relato de que grande parte dos pacientes que chegam para o atendimento na atenção primária apresentam, como principal queixa, tristeza (depressão) e/ou ansiedade, aparecendo também transtornos mais complexos como os problemas relacionados ao abuso de álcool, assim como os transtornos mentais graves e persistentes, como a esquizofrenia e as psicoses afetivas (transtorno bipolar do humor). Nos estudos farmacogenéticos de antidepressivos e antipsicóticos, as enzimas do citrocromo P450 (CYPs) tem se mostrado um dos alvos mais significativos nas alterações interindividuais dos parâmetros cinéticos de resposta às drogas. OBJETIVO: caracterizar a frequência de polimorfismos do CYP2D6 (*4, *6 e 17*) em usuários da terapêutica com psicotrópicos, principalmente antidepressivos tricíclicos e antipsicóticos. MÉTODOS: Estudo transversal, descritivo realizado no Município de São Luís (MA). RESULTADO: De um total de 105 prontuários, coletou-se amostra de 43 pacientes, a média de idade foi de 40,98 (±11,04) anos, sendo 24 (55,81%) do sexo masculino e 19 (44,19%) do sexo feminino. Em relação à farmacoterapia, todos os participantes (100%) estavam em consumo diário do antipsicótico haloperidol, dezessete (39,53%) pacientes faziam uso de risperidona e um (2,32%) paciente utilizava amitriptilina (antidepressivo tricíclico), todos os três medicamentos são substratos da enzima CYP2D6. Para o polimorfismo da CYP2D6, tivemos para o alelo 4 uma prevalência de 11 (25,48%), sendo que todos os pacientes que apresentaram esse polimorfismo são heterozigotos, ou seja, apresentaram um alelo polimórfico e outro normal. Para o alelo 17, tivemos uma prevalência de 4 (9,3%), sendo também todos os pacientes heterozigotos para esse alelo. O alelo 6 não apareceu em nenhum paciente do nosso estudo. Tivemos também dois pacientes que apresentaram os polimorfismos para os alelos *4 e *17 ao mesmo tempo. CONCLUSÃO: Este estudo pôde caracterizar a frequência de polimorfismos do CYP2D6 (*4, *6 e 17*) em usuários da terapêutica com psicotrópicos, incluindo antidepressivos tricíclicos e antipsicóticos, além de contribuir para uma maior adequação da relação dose/resposta ao medicamento, garantindo maior segurança e eficácia quanto ao uso de medicamentos, melhorando a qualidade de vida dos pacientes.
145

Bedeutung genetischer Polymorphismen im organischen Kationentransporter OCT1 für die Pharmakokinetik und Nebenwirkungen von Proguanil / Impact of genetic polymorphisms in organic cation transporter OCT1 on pharmacokinetics and side effects of Proguanil

Tann, Annabelle 23 January 2019 (has links)
No description available.
146

Spliced Leader (SL) RNA: análises de genes e regiões intergênicas com aportes na filogenia, taxonomia e genotipagem de Trypanosoma spp. de todas as classes de vertebrados. / Structural, phylogenetic and polymorphism analysis of Spliced Leader (SL) genes of Trypanosoma spp. isolated from vertebrate hosts.

Alvarez, Oneida Espinosa 21 June 2017 (has links)
Tripanossomas são parasitas obrigatórios de uma grande variedade de hospedeiros vertebrados e invertebrados sendo descritas até hoje centenas de espécies, genótipos, linhagens e DTUs. Análises moleculares foram chaves para perceber a complexidade deste gênero e necessários na predição de histórias evolutivas entre tripanossomas patogênicos e não patogênicos do velho e novo mundo. Além dos marcadores tradicionais (SSU rDNA e gGAPDH), o gene Spliced Leader (SL) tem sido útil na identificação e genotipagem de tripanossomatídeos, mas poucas espécies possuem genes SL bem estudados. Este trabalho caracterizou as estruturas primárias e secundárias do gene SL de várias espécies representantes dos principais clados de tripanossomas, evidenciando seu polimorfismo inter e intra-específico e mostrando sua utilidade como DNA barcoding. Os resultados obtidos permitiram a descrição de novas espécies (T. livingstonei e T. wauwau), a identificação de subgrupos nas DTUs de T. cruzi e suportaram os relacionamentos filogenéticos obtidos com os marcadores tradicionais. / Trypanosomes are obligate parasites found in a great variety of vertebrate and invertebrate hosts, with hundreds of species, genotypes, lineages and discrete typing units (DTUs) being described. Molecular analyses have been essential to understanding the complexity of trypanosomes and to predict the evolutionary history of the non-pathogenic and pathogenic species from the Old and New World. Besides traditional phylogenetic markers (SSU rDNA and gGAPDH), Spliced Leader (SL) gene has proven useful for identifying and genotyping trypanosomatids, but well defined SL sequences are available for only a few species. In this study, SL primary and secondary structures were determined for species representatives of the main trypanosome clades, showing inter and intra-specific variability that rendered them useful for DNA barcoding. SL results allowed the description of new trypanosome species (T. livingstonei and T. wauwau), the identification of subgroups in the T. cruzi DTUs, in addition to support the phylogenetic relationships obtained with traditional markers.
147

Biomarcadores genéticos na hemorragia subaracnoidea aneurismática em pacientes da Amazônia / Genetic biomarkers in patients with aneurysmal subarachnoid hemorrhage in the Amazon patients

Paschoal, Eric Homero Albuquerque 24 August 2017 (has links)
Hemorragia subaracnoidea aneurismática (HSAa) é considerada causa importante de morte e de sequelas neurológicas. A taxa de mortalidade desta doença pode alcançar 50% nos primeiros dois meses após sangramento de aneurisma encefálico. Apesar dos avanços científicos da modernidade, o resultado do tratamento da HSAa não mudou nos últimos anos. O presente estudo avaliou o papel de 14 biomarcadores genéticos, incluindo o polimorfismo (SNP) do gene eNOS, em pacientes da Amazônia com HSAa, para verificar as alterações alélicas associadas ao risco de vasoespasmo encefálico e déficit neurológico tardio. Avaliou-se a ancestralidade desta amostra de pacientes em que se utilizou 48 marcadores para identificar possível etnia associada à predisposição ao VE. Investigou-se 14 biomarcadores genéticos no tocante à resposta inflamatória encefálica na HSAa. Foram avaliados 265 doentes que foram divididos em dois grupos: grupo I (pacientes com vasoespasmo encefálico) e grupo 2 (pacientes sem vasoespasmo). A média das idades foi 51 anos, havia 224 mulheres (84%) e 124 pacientes (46,79%) apresentaram vasoespasmo encefálico (VE). A maior incidência de VE ocorreu na idade entre 50 e 59 anos. Tabagismo e hipertensão arterial sistêmica foram os fatores de risco mais associados à VE. Aneurismas encefálicos de tamanho pequeno e médio predominaram nesta casuística. As escalas amarela e vermelha do VASOGRADE associaram-se ao risco de VE (p < 0,001). Não houve variação na distribuição ancestral entre os grupos estudados e o que ocorre na população brasileira saudável na região Amazônica. O gene da eNOS com seus respectivos polimorfismos T-786C e 27VNTR4 correlacionaram-se com VE. Outros marcadores observados foram TP53, CASP8, ACE2, IL4 e XRCC1. O gene TP53 (modelo recessivo alelo 1) mostrou-se ser um fator protetor de VE, enquanto que genes com mutações INDEL CASP8 (modelo recessivo alelo 2) e o XRCC1 (modelo recessivo alelo 1) mostraram tendência ao desenvolvimento de VE com risco 2 vezes maior e 1,4 vezes maior que o grupo II (p < 0,001). Conclui-se que SNPs da eNOS se correlacionam com desenvolvimento de VE sintomático pós-HSAa. Este estudo também mostrou o papel dos marcadores inflamatórios na HSAa, o que auxiliaria na condução da terapia clínica. / Aneurysmal subarachnoid hemorrhage (aSAH) is a leading cause of premature death and neurological disability. It is considered as a devastating condition that accounts to 50% of mortality during the first two months after a hemorrhagic event. Despite foremost advances in the clinical management of post-aSAH patients, the rates of mortality and morbidity have not changed in recent years. This study appraised the role of 14 genetic biomarkers, including the eNOS polymorphism (SNP) between Amazon\'s patients with aSAH, as means to document how variant alleles are related to a higher disposition to cerebral vasospasm (CV) and delayed cerebral ischemia (DCI). 265 patients were evaluated and then divided into two clusters: Group I (with symptomatic CV) and group II (presenting no symptomatic CV). The median ages of patients were 51.61 years of age, 224 (84.52%) were women and 124 patients (46.97%) had symptoms of cerebral vasospasm (CV). Tobacco smoking and systemic arterial hypertension are the risk factors most associated to CV. In the course of this research, most aneurysms found were small and medium-sized. The score VASOGRADE yellow and VASOGRADE red presented a high risk of CV (p < 0.001). We established a panel of 48 ancestry informative markers for estimating which ethnicity could present a predisposition to CV. There was no variation in the ancestral distribution between study groups and healthy brazilian folk over the Amazon region. The eNOS gene with its polymorphisms T-786C and 27 VNTR4 were correlated to CV. Other markers were accomplished: TP53, CASP8, ACE2, IL4, and XRCC1. The TP53 gene (recessive genetic model allele 1) supporting evidence of the protective role to CV. Whilst other genes with INDEL mutation like as CASP8 (recessive model allele 2) and the XRCC1 (recessive model allele 1) indicated a propensity to spread out CV with odds 2-fold higher, and 1.414 times greater than group II (p < 0.001). It follows that eNOS SNPs correlate to a positive association with a syntomatic CV post-aSAH. Also, this study showed up the role of inflammatory markers at aSAH to a further educated therapeutic choice for a better clinical response
148

Etudes génétiques et immunomodulatoires de la ghréline sur les traits de production et de conformation en races bovines ainsi que sur la croissance chez le rat

Colinet, Frédéric 23 October 2008 (has links)
En production animale, notamment dans les filières bovines, il est dun intérêt économique daugmenter la quantité dhormone de croissance dans la circulation sanguine. La ghréline est un peptide principalement produit au niveau de la paroi stomacale. Ce ligand endogène au GHSR stimule la sécrétion hypophysaire de lhormone de croissance. Peptide orexigène, la ghréline est impliquée dans les mécanismes relatifs au maintien de lhoméostasie énergétique. Dans loptique daméliorer les performances animales, deux approches de la ghréline ont été effectuées. La première approche consiste en létude des gènes bovins codant pour la ghréline (bGHRL) et son récepteur (bGHSR). Ces deux gènes ont été respectivement localisés sur BTA 22 et BTA 1. Quatorze polymorphismes ont été détectés sur ces deux gènes et trois dentre eux affectent la structure primaire du GHSR bovin. Des associations, à différents niveaux de signification, entre certains de ces 14 sites polymorphiques et des traits de production et de conformation ont été mis en évidence au sein dun groupe de 127 taureaux Holstein sur base de leurs descendances directes présentes en Région Wallonne. La seconde approche aborde les effets dune immunisation passive contre la ghréline sur des rats mâles en croissance en comparaison à celles contre la leptine et la cholécystokinine. Lors dune alimentation équilibrée, le traitement envers la ghréline sur ces rats na pas influencé la croissance et lingestion par rapport aux animaux témoins. Des effets ont été observés entre les différentes immunomodulations au niveau des paramètres de croissance, dingestion et endocrinologiques. Les présents résultats invitent à de nouvelles investigations des gènes bGHRL et bGHSR sur des données relatives à dautres populations/races bovines et de limmunomodulation de la ghréline lors de conditions dexpérimentation différentes (alimentation déséquilibrée, stade physiologique, espèce, etc.). Ces investigations pourraient être valorisées en sélection et production animale mais également en médecine tant humaine que vétérinaire.
149

Association Of Cyp2e1, Nqo1 And Gst Genetic Polymorphisms With Risk Of Acute Lymphoblastic Leukemia In Turkish Children

Ulusoy, Gulen 01 March 2009 (has links) (PDF)
Acute lymphoblastic leukemia (ALL) is the most common type of cancer affecting children in the world and in our country. The exact molecular etiology of the disease still remains to be elucidated. This study hypothesized that four genes, namely CYP2E1*5B, *6, and *7B, NQO1*2 SNPs, GSTM1 null and GSTT1 null, alone or in combination, could contribute to the risk of development of childhood ALL. Also interactions of these polymorphisms with non-genetic risk factors were investigated. The genotyping of these polymorphisms were done on 209 healthy subjects, and 185 patients with childhood ALL, in Turkish population. Venous blood samples were collected and genomic DNA was isolated from these samples. Genotyping was done by PCR-RFLP techniques. In the case-control analyses for the risk of development of childhood ALL, only GSTT1 null was found to be associated with the development of disease (OR= 1.8, p=0.01). CYP2E1*5B and *6 combination showed an increased risk of 2.7 fold (p= 0.04). Also co-presence of CYP2E1*6-GSTT1 and CYP2E1*7B-GSTT1 polymorphisms increased the risk significantly above 4.0 fold. The risk increased more to 7.6 fold, when CYP2E1*5B,*6 and GSTT1 null were considered together, with borderline significance (p=0.04). When interaction of exposure to cigarette smoke and genetic polymorphisms were investigated, NQO1*2 and GSTM1 null were turned out to be significant risk factors for the development of disease when the parental or child&rsquo / s postnatal exposure to cigarette smoke was considered. This study presented several new findings to the literature in terms of genetic epidemiology of childhood ALL. The present work would also contribute to public health in determining the susceptibility of the Turkish population to childhood ALL.
150

Genetic Polymorphisms Of Alcohol Inducible Cyp2e1 In Turkish Population

Ulusoy, Gulen 01 January 2005 (has links) (PDF)
Cytochrome P4502E1 (CYP2E1), the ethanol-inducible isoform of cytochrome P450 superfamily, catalyzes many low molecular weight endogenous and exogenous compounds, including ethanol, acetone, drugs like acetaminophen and chlorzoxazone, and industrial solvents like benzene and styrene, most of which are carcinogenic. Besides, it has a high capacity to produce reactive oxygen species. CYP2E1 is induced by ethanol and isoniazid, as well by some pathophysiological conditions like diabetes and starvation. CYP2E1 gene shows genetic polymorphisms which are thought to play a major role in interindividual variability in drug response and in susceptibility to chemical-induced diseases, like several types of cancers. It is well established that CYP2E1 polymorphisms vary markedly in frequency among different ethnic and racial groups. Therefore, in this study, the frequency of two important CYP2E1 polymorphisms / the single nucleotide polymorphisms C-1019T / G-1259C in 5&rsquo / -flanking region and T7678A poymorphism in intron 6, in Turkish population was investigated. For this purpose, whole blood samples were collected from 132 healthy volunteers representing Turkish population and genomic DNA for each subject was isolated in intact form. The genotypes were determined by PCR amplification of corresponding regions followed by restriction endonuclease RsaI, PstI (for C-1019T / G-1259C SNPs) and DraI (for T7678A SNP) digestions. The genotype frequencies, for C-1019T / G-1259C SNPs, which are in complete linkage disequilibrium, were investigated on 116 DNA samples, and determined as 97.4% for homozygous wild type (c1/c1), 2.6% for heterozygotes (c1/c2) and 0.0% for homozygous mutants (c2c2). The allele frequency of wild type allele (c1) was calculated as 98.7% and that of mutated allele (c2) as 1.3%. The genotype frequencies for T7678A SNP, investigated in 108 DNA samples were determined as 80.6% for homozygous wild type (DD), 19.4% for heterozygotes (CD) and 0.0% for homozygous mutants (CC). The corresponding allele frequencies were 90.3% for wild type allele (D), and 9.7% for mutated allele (C). Genotype frequencies of both polymorphisms fit Hardy-Weinberg equation and showed no significant difference with respect to gender. The genotype distributions of both polymorphisms showed similarity when compared to other Caucasian populations like French, Swedish, German, and Italian populations, while both polymorphisms studied differed significantly from Chilean, Japanese, Taiwanese and Chinese populations, as compared with Chi-Square test.

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