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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.
11

Enhancing Blood Outgrowth Endothelial Cells for Optimal Coating of Blood Contacting Surfaces

Yuan, Yifan January 2017 (has links)
Implantable cardiovascular biomaterials have been widely applied in multiple cardiovascular disorders such as coronary artery disease, heart failure, and abdominal aortic aneurysms. However the failure modes of cardiovascular biomaterials are not uncommon, which is mainly due to the complications on blood-contacting surfaces such as thrombosis, calcification, and inflammation. Endothelium locates the inner surface of vessel lumen and is a critical regulator of vascular homeostasis. However, a readily available functional autologous source of endothelium has been hard to achieve. Human blood outgrowth endothelial cells (BOECs), cultured from peripheral blood mononuclear cells are proliferative and express endothelial protein profiles and as such are a very promising novel cell source for cardiovascular biomaterials coating. Endothelial nitric oxide synthase (eNOS) is an important regulator of vascular homeostasis and loss of eNOS activity is a hallmark of endothelial dysfunction. My data demonstrated that BOECs express markedly lower eNOS protein, mRNA as well as activity levels when compared to mature endothelial cells (ECs). My first project was to use transient transfection methods along with minicircle DNA to enhance eNOS expression levels in BOECs. Two promoters were tested in BOECs, the CMV promoter (pMini-CMV-eNOS) and the EF1α promoter (pMini-EF1α-eNOS). Transfection with pMini-CMV-eNOS achieved 24.8 ± 5.1 times more eNOS expression when compared to null transfected cells at 24 hours, a marked improvement over that achieved with conventional PVAX plasmid (10.2 ± 4.7 fold increase) or pMini-EF1α-eNOS (8.2 ± 1.2 fold increase both compared to null transfected control). pMini-CMV-eNOS mediated overexpression improved cell migration and network formation. When cultured on Osteopontin (OPN) coated surfaces, transient transfection with plasmid eNOS in BOECs can markedly enhance cell spreading and adhesion to ECM modified surfaces. These results suggest that eNOS expression in BOECs is suboptimal and BOECs may be functionally improved by techniques to enhance expression of this critical homeostatic regulator. Extracellular matrix (ECM) proteins have been shown to negatively regulate eNOS expression and NO production in mature ECs. In addition, the deposition of Col IV and Col I in BOECs is higher compared to that in mature ECs. Thus, I have proposed that the lower eNOS expression/activity in BOECs compared to mature ECs is due to higher ECM deposition. When grown on fibronectin, type I collagen, type IV collagen and laminin, significantly decreased eNOS protein in HUVECs were found compared to cells on polystyrene. Interestingly, when cultured on polystyrene, BOECs express significantly more extracellular matrix (ECM) proteins especially type I collagen compared to mature ECs. Blocking collagen synthesis significantly enhanced eNOS expression in BOECs (1.77 ± 0.41 fold increase). My results suggest that the regulation of eNOS in BOECs and mature ECs is similar and the reduced eNOS level in BOECs may be due to their increased collagen production. ECM proteins regulate intracellular signaling transduction primarily through integrin signaling associated with focal adhesion complexes. I have proposed that ECM proteins regulation on eNOS signaling in BOECs and mature ECs is through integrin and integrin-associated proteins. Matrix mediated eNOS downregulation was blocked by β1 integrin siRNA and focal adhesion kinase siRNA transfection in both BOECs and HUVECs. In addition, inhibitors of actin polymerization (e.g. ROCK inhibitors and cytochalasin D) block the effect of ECM on eNOS signaling. Taken together, my results suggest that ECM proteins regulate eNOS expression via a β1 integrin/FAK/actin polymerization dependent mechanism.
12

Specializations for alternate trophic niches by two forms of threespine stickleback, Gasterosteus, co-existing in Enos Lake, Vancouver Island

Bentzen, Paul January 1982 (has links)
Two morphologically and ecologically distinct forms of threespine stickleback (Gasterosteus), a "limnetic" form and a "benthic" form, co-exist in Enos Lake on Vancouver Island. I used three experiments to compare the feeding performance of the two forms, to test the hypothesis that limnetics are adapted to planktivory and benthics are adapted to foraging on benthic substrates. The results support this conclusion. When tested for maximum prey size, benthics were able to consume larger prey (relative to their body size) than limnetics. Benthics were also more successful than limnetics in foraging on a benthic substrate. When allowed to forage on a detritus substrate for a fixed time interval, benthics of both sexes captured more prey than male limnetics, despite the fact that male limnetics directed as many feeding strikes at the substrate as did the benthics. Female limnetics did not forage on the substrate at all. In contrast, limnetics were more successful in feeding on plankton than benthics. When held in mesh enclosures suspended in the water column of Enos Lake, limnetics consumed more plankton than benthics. "Small" limnetics (26-35 mm standard length) consumed nearly four times more plankton than "large" limnetics (44-50 mm standard length). The small limnetics were all either mature females or immature males; the large limnetics were all mature males. These results, along with morphological, biochemical, ecological and behavioural data obtained in other studies, support the conclusion that the two forms of Gasterosteus in Enos Lake are distinct biological species. The results of this study also support another (unexpected) conclusion: mature male and female limnetics also differ in feeding behaviour. Female limnetics appear to be almost totally planktivorous; whereas, male limnetics are intermediate between female limnetics and benthics (both sexes) in feeding behaviour. / Science, Faculty of / Zoology, Department of / Graduate
13

PPAR gamma AND eNOS CONTRIBUTE TO THE RESOLUTION OF CHRONIC INFLAMMATION.

Evans, Kyle William January 2011 (has links)
Chronic inflammation follows defined phases of induction, inflammation, and resolution. The resolution phase requires cycloxygenase-2 (COX-2) activity. This study aims to address what other molecules are required for a functional resolution phase. We demonstrated that in murine collagen-induced arthritis the transcription factor, PPARgamma plays a role in the resolution phase. Inhibition of COX-2 activity results in fewer PPARgamma positive cells in the arthritic synovium. Treatment with a PPARgamma antagonist, SR202, alone, also disrupts the process of resolution. PPARgamma antagonist treatment results in a decrease in eNOS phosphorylation within the arthritic synovium. These observations indicate that PPARgamma may function to regulate eNOS activity. The source of pro-resolving nitric oxide is eNOS but not, iNOS. The effect of COX-2 inhibition on the resolution phase is ameliorated by injection of a PGE2 analog. Restoration of PGE2 levels results in an increase in PPARgamma positive cells in the arthritic synovium which correlates with this restoration of resolution. Thus, this study provides in vivo evidence for the pro-resolving role of PPARgamma and its relationship with PGE2 and eNOS. / Microbiology and Immunology
14

Análise estatística de uma série histórica de precipitação horária na cidade de São Paulo (1970-2009) / Statistical analysis of historical series of hourly precipitation in the city of São Paulo (1970-2009)

Mendes, Daniel 04 October 2013 (has links)
A complexidade de compreensão durante a observação realizada a partir da identificação de um possível quadro de evolução em um sistema climático marcado por uma série temporal longa de uma determinada variável ambiental deve-se ao fato do ambiente sofrer múltiplas interações físico-químicas que naturalmente ocorrem nas escalas global, regional e local. Na intenção de compreender alguns elementos dessa dinâmica foram analisadas algumas hipóteses que podem nos aproximar de possíveis explicações a respeito do contexto que emerge a partir da realidade observada. Neste contexto foi analisada a hipótese de que o ambiente fisicamente alterado pelo homem possa estar influenciado no número de episódios de chuvas nas suas diversas intensidades durante o intervalo de uma hora. A segunda hipótese analisou a possibilidade das alterações em grandes escalas envolvendo às flutuações de temperatura observadas na superfície do mar (TSM) de uma região específica (Niño3.4) localizada no pacífico equatorial possam estar influenciando e/ou intensificando os episódios de chuva em escala local. No entanto, a partir dessas possibilidades o objetivo foi a de analisar através do uso de métodos estatísticos, a partir da aplicação de ajustes e correlações lineares, a identificação de tendências positivas ou negativas, no quadro de cada tipo de chuva e, posteriormente, no quadro das variações de TSM, da região Niño3.4. O segundo procedimento adotado avaliou de uma maneira qualitativa a possibilidade de haver correlações positivas entre os dois ajustes lineares analisados. Os resultados indicaram que a variabilidade climática anual da região Niño3.4 durante a série completa (1970-2009) apresentou um quadro de aquecimento (ajuste positivo). Por outro lado, também foi observado o aquecimento da TSM durante séries específicas da série completa identificadas como fase Neutra, ENOS e La Niña. No entanto, a série especifica relativa à fase El Niño apresentou um comportamento inverso, no caso, um resfriamento na TSM durante o período analisado. Neste caso, foi constatado que o aquecimento anual da TSM da região Niño3.4 ocorre em função do aquecimento observado durante as anomalias negativas (La Niña). O quadro dos ajustes lineares de cada tipo de chuva revelou uma diminuição horária na frequência de chuvas muito fracas (nevoeiros e neblinas), de chuvas fracas (chuviscos e garoas) e de chuvas moderadas (tempestades leves oriundas de nimbostratus). Por outro lado, o quadro de ajustes lineares para chuvas mais intensas foram positivas, como no caso, de chuvas fortes (tempestades ordinárias) e muito fortes (tempestades severas). / The complexity of understanding during the observation carried out from the identification of a possible behavior of evolution in a climatic system marked by a series storm long of a determined environmental variable is due to the fact of the environment suffer multiple interactions chemical-physically what naturally take place in the global, regional and local scales. In the intention of understanding some elements of this dynamic one there were analyzed some hypotheses that can bring near us of possible explanations as to the context that surfaces from the observed reality. In this context it was analyzed the hypothesis of which the environment physically altered by the man could be influenced the number of episodes of rains in his several intensities during the interval of an hour. The second hypothesis analyzed the possibility of the alterations in great scales wrapping to the fluctuations of temperature observed in the surface of the sea (TSM) of a specific region (Niño3.4) located in the Pacific Ocean be able to be influencing and / or intensifying the episodes of rain in local scale. However, from these means the objective was it of analyzing through the use of statistical methods, from the application of agreements and linear correlations, the identification of positive or negative tendencies, in the picture of each type of rain and, subsequently, in the picture of the variations of TSM, of the region Niño3.4. The second adopted proceeding valued in a qualitative way the possibility to be positive correlations between two linear analyzed agreements. The results indicated that the climatic annual variability of the region Niño3.4 during the complete series (1970-2009) presented a picture of heating (positive agreement). On the other side, also the heating of the TSM was observed during specific series, of the complete series, identified like phases Neuter, ENOS and La Niña. However, the series specify relative to the phase El Niño he presented a reverse behavior, in the case, a cooling in the TSM during the analyzed period. In this case, it was noted that the annual heating of the TSM of the region Niño3.4 takes place in function of the heating observed during the negative anomalies (La Niña). The picture of the linear agreements of each type of rain revealed a reduction hourly in the frequency of very weak rains (thick fogs and fogs), of weak rains (drizzles and drizzles) and of moderate rains (light originating storms of nimbostratus). On the other side, the picture of linear agreements for more intense rains they were positive, since in the case, of strong rains (ordinary storms) and very strong (severe storms).
15

POLIMORFISMO DO GENE eNOS G894T (Glu298Asp) EM PACIENTES SINTOMÁTICOS PARA ATEROSCLEROSE / Polymorphism of the gene eNOS G894T (Glu298Asp) in symptomatic patients to atherosclerosis

Campedelli, Fabio Lemos 12 August 2016 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-11-30T16:52:02Z No. of bitstreams: 1 FÁBIO LEMOS CAMPEDELLI.pdf: 8948383 bytes, checksum: 229016125b12d4f344bb1c157148ddad (MD5) / Made available in DSpace on 2016-11-30T16:52:02Z (GMT). No. of bitstreams: 1 FÁBIO LEMOS CAMPEDELLI.pdf: 8948383 bytes, checksum: 229016125b12d4f344bb1c157148ddad (MD5) Previous issue date: 2016-08-12 / INTRODUCTION: Atherosclerotic disease (AD) with its cardiovascular complications is responsible for 17.5 million deaths a year, according to the World Health Organization (WHO). There is consensus that atherosclerosis involves multiple pathogenic processes initiated by endothelial dysfunction, with inflammation and vascular proliferation determining alterations in the matrix, with consequent formation of the atheromatous plaque and its clinical implications. Risk factors such as hypertension, diabetes mellitus, dyslipidemia and smoking are widely known. Currently genotyping, which is not directly related to these factors, is not accepted to estimate the risk of cardiovascular diseases, but strong evidence indicates several polymorphic genes as factors of risk and progression leading to complications of the disease. Among the genes involved, eNOS (endothelial nitric oxide synthase gene), which is responsible for the production of endothelial nitric oxide (NO, an important arterial vasodilator), when presented in polymorphic variation can determine production malfunction and predisposition to AD. OBJECTIVES: To analyze the G894T polymorphism of eNOS gene in groups of individuals diagnosed with atherosclerosis and in the control group. MATERIALS AND METHODS: 200 blood samples were collected from patients previously diagnosed with DA and 100 from the control group. The genotyping analysis for polymorphism of eNOS gene was determined by PCR. RESULTS: After analysis of polymorphism between the DA and control groups and association with variables such as gender, relation with smoking, smoking history and alcohol consumption, statistical difference were found in the distribution of the case and control groups (p = 0.0378) and in non-smoking patients (p = 0.0263). In the other associations no statistically significant difference was found. CONCLUSION: In the population studied, the frequency of the heterozygous genotype (GT) was much higher than in the other popualations (GG and TT) in both groups (case and control). The GG genotype showed greater susceptibility to AD. The association of GG genotype in nonsmokers also showed greater susceptibility. Gender, alcohol consumption, smoking and smoking history did not influence AD. / Campedelli FL. Polimorfismo do gene eNOS G894T (Glu298Asp) em pacientes sintomáticos para aterosclerose [dissertação]. Goiânia: Pontifícia Universidade Católica, PUC-GO; 2016. INTRODUÇÃO: A doença aterosclerótica (DA) com suas complicações cardiovasculares é responsável por 17,5 milhões de mortes por ano segundo a Organização Mundial de Saúde (OMS). É consenso que a aterosclerose envolve múltiplos processos patogênicos que se iniciam pela disfunção endotelial, com inflamação e proliferação vascular determinando alterações da matriz com consequente formação da placa ateromatosa e suas repercussões clínicas. Fatores de risco como a hipertensão arterial, diabetes mellitus, dislipidemias e tabagismo são amplamente conhecidos. Atualmente a genotipagem, não relacionada diretamente a estes fatores, não é aceita para estimativa de risco das doenças cardiovasculares, porém fortes evidências relacionam diversos genes polimórficos, como fator de risco e evolução para complicações da doença. Dentre os genes envolvidos o eNOS (gene da síntese de óxido nítrico endotelial), responsável pela produção de Óxido nítrico (NO), endotelial (importante vasodilatador arterial), quando se apresenta em variação polimórfica pode determinar mal funcionamento da produção e predispor a DA. OBJETIVOS: Analisar o polimorfismo G894T do gene eNOS nos grupos de indivíduos com diagnóstico de aterosclerose e no grupo controle. MATERIAIS E MÉTODOS: Foram coletados amostras de sangue periférico de 200 pacientes com DA previamente diagnosticados e 100 amostras de grupo controle. A análise de genotipagem para o polimorfismo do gene eNOS foi determinada por PCR. RESULTADOS: Após análise do polimorfismo entre os grupos com DA e grupo controle, e associação com as variáveis gênero, relação com hábito de fumar, carga tabágica e consumo de bebida alcóolica, foram encontrados diferença estatísticas na distribuição dos grupos caso e controle (p=0,0378) e nos pacientes não tabagistas (p=0,0263). Nas demais associações não houve diferença estatisticamente significativa. CONCLUSÃO: Na população estudada evidenciou a frequência do genótipo heterozigoto (GT) muito superior aos demais (GG e TT) em ambos os grupos (caso e controle). O genótipo GG demonstrou maior suscetibilidade à DA. A associação do genótipo GG em não tabagista também apresentou maior suscetibilidade. O gênero, o etilismo, o hábito de fumar e carga tabágica não influenciaram na DA.
16

ATEROSCLERÓTICOS HIPERTENSOS E OS POLIMORFISMOS DOS GENES eNOS (G894T e T786C), GSTT1 e GSTM1

Morais, Monize Prado de 04 November 2016 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2017-02-23T18:23:59Z No. of bitstreams: 1 MONIZE PRADO DE MORAIS.pdf: 8293372 bytes, checksum: fab38792d3267479760282fcdf0829b1 (MD5) / Made available in DSpace on 2017-02-23T18:23:59Z (GMT). No. of bitstreams: 1 MONIZE PRADO DE MORAIS.pdf: 8293372 bytes, checksum: fab38792d3267479760282fcdf0829b1 (MD5) Previous issue date: 2016-11-04 / The atherosclerosis is a multifactorial chronic inflammatory disease that occurs in response to the endothelial aggression, compromising the intimate layer of media and large caliber arteries. The systemic arterial hypertension is considered the main risk factor for the formation of atherogenic plates, increasing the risk of cardiovascular events between two and three times. Several genes are involved in the process of atherogenesis and hypertension, this research studies some polymorphisms for candidates genes that participates in the process which involves both pathologies, the polymorphisms G894T and T-786C of the genes eNOS, and the polymorphisms of the genes GSTT1 and GSTM1. The objective of this work was to analyze and associate such polymorphisms in hypertensives atherosclerotics individuals and in individuals with absence of hypertension and atherosclerosis. This study deals with the control-case in which 267 samples were analyzed, of which 100 of control group and 167 of the group case. The samples were submitted to DNA extraction, then to PCR and analyzed in 1,5 % agarose gel, stained with ethidium bromide at 5µg/mL. Soon after, the results were compared using the Chi-Square test and the G-test. The results point to a prevalence of genotype GT (76%) and the mutant allele T (56%) of the polymorphism T786C (eNOS), with the p equal to 0.03. For the polymorphism T786C eNOS, the heterozygote genotype (TC) represented 58% of the sample, with the allele C prevailing with 61%, but there was no significant statistics. In the analysis of the gene GSTT1 prevailed the present genotype (84%) as well as the presence of GSTM1 (73%), in both associations the p detected was less than 0.05. Smoking association was found only in the polymorphism GSTM1. Regarding to alcoholism, there was only association between GSTT1 and the habit of drinking. There are many possible interactions of these polymorphisms and the development of atherosclerosis and hypertension, but more studies are necessary for further elucidation of these associations. / A aterosclerose é uma doença inflamatória crônica multifatorial que ocorre em resposta à agressão endotelial, acometendo a camada íntima de artérias de médio e grande calibre. A hipertensão arterial sistêmica é considerada o principal fator de risco para a formação das placas aterogênicas, aumentando o risco de eventos cardiovasculares em duas a três vezes. Vários genes estão envolvidos no processo da aterogênese e da hipertensão, nesta pesquisa foram estudados alguns polimorfismos de genes candidatos partícipes do processo que envolve ambas patologias, os polimorfismos G894T e T786C do gene eNOS, e os polimorfismos dos genes GSTT1 e GSTM1. O objetivo deste trabalho foi analisar e associar tais polimorfismos em indivíduos ateroscleróticos hipertensos e em indivíduos com ausência de hipertensão e aterosclerose. Este estudo trata-se de um caso-controle onde foram analisadas 267 amostras sendo 100 do grupo controle e 167 do grupo caso. As amostras foram submetidas à extração de DNA, em seguida à PCR e analisadas em gel de agarose a 1,5%, corados com brometo de etídio a 5 g/mL. Logo depois os resultados foram comparados utilizando o Teste Qui-Quadrado e o Teste G. Os resultados apontaram para uma prevalência do genótipo GT (76%) e do alelo mutante T (55,5%) do polimorfismo G894T (eNOS), com o p igual a 0,03. Já para o polimorfismo T786C (eNOS), o genótipo heterozigoto (TC) representou 58% da amostragem, com o alelo C prevalecendo com 61%, porém não houve significância estatística. Já na análise do gene GSTT1 houve prevalência do genótipo presente (84%) assim como da presença de GSTM1 (73%), sendo que em ambas associações o p detectado foi menor que 0,05. Foi encontrada associação entre o tabagismo apenas com o polimorfismo GSTM1. Quanto ao alcoolismo houve associação somente entre o GSTT1 e o hábito de beber. São muitas as possíveis interações desses polimorfismos e o desenvolvimento da aterosclerose e hipertensão, mas ainda são necessários mais estudos para uma maior elucidação destas associações.
17

Aterosclerose: Análise do polimorfismo T786C do gene eNOS.

Barbosa, Andreia Marcelino 03 March 2017 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2017-06-01T14:16:03Z No. of bitstreams: 1 ANDREIA MARCELINO BARBOSA.pdf: 784297 bytes, checksum: e401bab7d446314e9ec1076b99966617 (MD5) / Made available in DSpace on 2017-06-01T14:16:04Z (GMT). No. of bitstreams: 1 ANDREIA MARCELINO BARBOSA.pdf: 784297 bytes, checksum: e401bab7d446314e9ec1076b99966617 (MD5) Previous issue date: 2017-03-03 / Coronary artery disease (CAD) is the most common form of cardiovascular disease. CAD is a multifactorial disease of complex etiology, influenced by genetic and environmental determinants. Atherosclerotic lesion is the most common abnormality found in the arteries resulting from two basic processes: cholesterol accumulation and the proliferation of smooth muscle cells in the tunica intima, thus developing on a substrate formed of these cells, leukocytes derived from blood and a variable amount of connective tissue forming a fibrous plaque that projects into the lumen modifying the middle tunica and leading to a series of circulatory complications. Nitric oxide (NO) produced by nitric oxide endothelial synthase (eNOS) is known to alter blood flow, altering processes involved in atherosclerosis, and is considered an important atheroprotective. One of the polymorphisms most studied is a SNP in the promoter region (T786C), often associated with the development of coronary disease. T786C is an important thymine to cytosine point mutation at codon-786 in the 50-flanking region of the eNOS gene, which could significantly reduce the activity of the gene promoter and serum nitric oxide level. This polymorphism significantly reduces the activity of the eNOS promoter gene. We collected 297 peripheral blood samples, from patients referred to the cardiology service and peripheral vascular surgery, of the Angiogyn Clinic in the city of Goiânia, with previous diagnosis of atherosclerotic disease based on clinical examination and confirmed by imaging methods (197 samples) and control group (100 samples). The collected samples were submitted to PCR to verify presence of polymorphisms. The results were compared using the Chi-Square test and Test G, with the aid of Bioestat software (version 5.3; biocistron.blogspot.com/). In the present study the frequency of the TC genotype was more frequent. In the control group, the higher frequency was observed in the TC genotype. This difference was not statistically significant. Making a relation between the TC/TT and CC genotypes in the case group; TC/TT and CC in the control group, we found that this difference is also not significant. No significant difference was found when genotypes (TT, TC and CC) were analyzed, associated with gender and smoking. The results were not significant because a traditional standard was used, where there is usually twice as many cases for the number of controls, and also because atherosclerosis is a very common disease. Several studies have indicated that when the n worked is double the control in relation to the number of cases, this would lead to a better epidemiological statistic. We can also conclude that there is a strong tendency of the T allele, in single dose or double dose, in association with atherosclerosis. / A doença arteriosclerótica coronariana (DAC) é a forma mais comum de doença cardiovascular. A DAC é uma doença multifatorial de etiologia complexa, influenciada por determinantes genéticos e ambientais. A lesão aterosclerótica é a anormalidade mais comum encontrada nas artérias decorrente inicialmente de dois processos básicos: acúmulo de colesterol e a proliferação de células musculares lisas na túnica íntima, desenvolvendo-se, portanto, sobre um substrato formado dessas células, leucócitos derivados do sangue e de uma quantidade variável de tecido conectivo formando uma placa fibrosa que se projeta para dentro do lúmen modificando a túnica média e levando a uma série de complicações circulatórias. O óxido nítrico (NO) produzido pelo óxido nítrico endotelial sintase (eNOS) é conhecido por alterar o fluxo sanguíneo, alterando processos envolvidos na aterosclerose, sendo considerado um importante ateroprotetor. Um dos polimorfismos mais estudados é um SNP na região promotora (T786C), frequentemente associado ao desenvolvimento de doença coronariana. O T786C é uma mutação de ponto importante, de timina para citosina, no códon-786 na região 50-flanqueadora do gene eNOS, o que poderia reduzir significativamente a atividade do promotor do gene e nível sérico de óxido nítrico. Esse polimorfismo reduz significativamente a atividade do gene promotor da eNOS. Foram coletadas 297 amostras de sangue periférico, de pacientes referenciados ao serviço de cardiologia e cirurgia vascular periférica, da Clínica Angiogyn no município de Goiânia, com diagnóstico prévio de doença aterosclerótica baseados em exame clínico e confirmados através de métodos de imagem (197 amostras) e grupo controle (100 amostras). As amostras coletadas foram submetidas a PCR para verificar presença dos polimorfismos. Os resultados foram comparados utilizando o Teste Qui-Quadrado e Teste G, com o auxílio do software Bioestat (version 5.3; biocistron.blogspot.com/). No presente estudo a frequência do genótipo TC apresentou-se mais frequente. Já no grupo controle a maior frequência foi observada no genótipo TC. Sendo essa diferença não estatisticamente significativa. Fazendo uma relação entre os genótipos TC/TT e CC no grupo caso; TC/TT e CC no grupo controle, obteve-se que essa diferença também não é significativa. Não foi encontrada nenhuma diferença significativa quando analisados os genótipos (TT, TC e CC) associados a variável gênero sexual e tabagismo. Os resultados não foram significativos porque foi utilizado um padrão tradicional, onde normalmente existe o dobro de casos para o número de controles, e também devido à aterosclerose ser uma doença muito comum. Vários trabalhos indicaram que quando o n trabalhado é o dobro de controle em relação ao número de casos, isso levaria a uma melhor estatística epidemiológica. Podemos concluir também que há forte tendência do alelo T, em dose única ou dose dupla, em associação com aterosclerose.
18

ASSOCIAÇÃO DO POLIMORFISMO G894T DO GENE eNOS COM GLAUCOMA PRIMÁRIO DE ÂNGULO ABERTO

Almeida Filho, Eduardo Eustáquio de 12 June 2017 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2017-09-04T12:48:49Z No. of bitstreams: 1 EDUARDO EUSTÁQUIO DE ALMEIDA FILHO.pdf: 1586241 bytes, checksum: ac6c2a57234dbdb8dcad9ea043e60dee (MD5) / Made available in DSpace on 2017-09-04T12:48:49Z (GMT). No. of bitstreams: 1 EDUARDO EUSTÁQUIO DE ALMEIDA FILHO.pdf: 1586241 bytes, checksum: ac6c2a57234dbdb8dcad9ea043e60dee (MD5) Previous issue date: 2017-06-12 / Glaucoma can be defined as a progressive degeneration of the retinal nerve fiber layer that results in death of the ganglion cells, eventually causing blindness. It is the first cause of irreversible blindness in the world. The pathophysiology of glaucoma is not fully elucidated, although several risk factors such as genetic, racial, age and increased intraocular pressure are known. This study was a case-control study in which 116 samples were analyzed: 32 patients with primary open-angle glaucoma (18 males and 14 females; age range 65-89 years) and 84 controls (44 males and 40 females; Aged 65-86 years). The samples were submitted to DNA extraction, then to PCR and analyzed on 2% agarose gel, stained with 5 g / mL ethidium bromide. The G894T polymorphism of the eNOS gene was found in the 0% (0/32) group of homozygotes for the wild-type (GG) allele, 93.75 % (30/32) of heterozygotes (GT) and 6.25% (2/32) homozygous for the polymorphic (TT) allele. In the control group, 9.52% (8/84) of homozygotes for the wild-type (GG), 82.14% (69/84) heterozygotes (GT) and 8.33% (7/84) homozygotes for the polymorphic allele (TT). There was no statistically significant difference. As for the allelic frequency of the eNOS gene (G894T) in the case group, 46.8% of the (G) allele and 53,2% of the T allele were found, whereas the G allele frequency was 50.5% and 49, 5% of the T allele. There was no statistically significant difference. Likewise, there was no statistically significant relationship between the polymorphism with hypertension, gender, diabetes and ethnicity. There are many possible interactions of these polymorphisms and the development of glaucoma, but further studies are needed to further elucidate these associations. / Glaucoma pode ser definido como uma degeneração progressiva da camada de fibras nervosas da retina que resulta na morte das células ganglionares, eventualmente causando cegueira. É a primeira causa de cegueira irreversível no mundo. A fisiopatologia do glaucoma não é totalmente elucidada, embora se tenha conhecimento de vários fatores de risco como alterações genéticas, raciais, idades e aumento da pressão intraocular. Este estudo trata-se de um casocontrole onde foram analisadas 116 amostras sendo 32 pacientes com glaucoma primário de ângulo aberto (18 homens e 14 mulheres; variação de idade 65-89 anos) e 84 controles (44 masculinos e 40 femininos; variação de idade 65-86 anos). As amostras foram submetidas à extração de DNA, em seguida à PCR e analisadas em gel de agarose a 2%, corados com brometo de etídio a 5 g/mL. Na investigação do polimorfismo G894T do gene eNOS foi encontrado no grupo caso 0% (0/32) de homozigotos para o alelo selvagem (GG), 93,75% (30/32) de heterozigotos (GT) e 6,25% (2/32) homozigotos para o alelo polimórfico (TT). No grupo controle foi encontrado 9,52% (8/84) de homozigotos para o alelo selvagem (GG), 82,14% (69/84) de heterozigotos (GT) e 8,33% (7/84) de homozigotos para o alelo polimórfico (TT). Não houve diferença estatística significante. Quanto a frequência alélica do gene eNOS (G894T) no grupo caso foi encontrado 46,8% do alelo selvagem (G) e 53,2% do alelo T, já no grupo controle a frequência do alelo G foi de 50,5% e 49,5% do alelo T. Não houve diferença estatística significante. Da mesma forma não houve relação estatisticamente significativa do polimorfismo com hipertensão arterial, gênero, diabetes e etinia. São muitas as possíveis interações desses polimorfismos e o desenvolvimento de glaucoma, mas ainda são necessários mais estudos para uma maior elucidação destas associações.
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Einfluss des eNOS T-786C - Polymorphismus auf Morbidität und Mortalität kardiochirurgischer Patienten. / Clinical relevance of eNOS T-786C polymorphism for hospital mortality and morbidity in cardiac surgical patients.

Henker, Christian 06 July 2011 (has links)
No description available.
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Obésité, risque athérogène et effet thérapeutique direct de l’exercice physique : étude sur la contribution des voies signalétiques Akt/eNOS et NADPH oxydase pour expliquer les mécanismes vasculo-protecteurs de l’exercice physique chez le rat rendu obèse par une alimentation enrichie en graisse / Obesity, atherogenic risk and direct therapeutic effect of the physical exercise

Touati, Sabeur 24 November 2010 (has links)
La prévalence de l’obésité est en constante augmentation dans les pays occidentaux, en raison d’une sédentarisation accompagnée d’une alimentation malsaine. L’obésité est souvent associée à une dysfonction endothéliale et à un risque athérogène élevé. Plusieurs observations cliniques ont montré que la modification du mode de vie, incluant la pratique régulière d’une activité physique et l’adoption d’un mode alimentaire sain, représente une stratégie efficace pour combattre l’obésité et ses complications cardiovasculaires. Cependant, de nombreux mécanismes précisant les effets thérapeutiques directs de l’exercice physique sur le risque athérogène lié à l’obésité sont encore largement inconnus. Le but principal de ce travail a donc été d’identifier, en utilisant un modèle de rat rendu obèse par un régime enrichi en graisse, les mécanismes athéro-protecteurs de l’exercice physique seul et/ou associé à une modification du régime alimentaire (du régime riche en graisse au régime standard). Nos résultats montrent que l’exercice physique, indépendamment de la diète utilisée, corrige la dysfonction endothéliale installée au cours de l’obésité. Cet effet bénéfique a été associé à une diminution du stress oxydatif au niveau vasculaire. En effet, nos résultats indiquent que l’exercice diminue l’activité de la NADPH oxydase au niveau aortique. De plus, nous montrons pour la première fois que l’exercice physique seul, indépendamment de la diète utilisée, est capable de moduler la translocation de la sous-unité de la NADPH oxydase p47phox (principal acteur dans l’activation de ce complexe enzymatique) vers la membrane. Nos résultats indiquent également que l’exercice physique, avec ou sans modification du régime, améliore la voie Akt/eNOS phosphorylée, suggérant une augmentation de la production du NO. Ainsi, l’exercice physique, même sans l’associer à un changement du mode alimentaire, peut être considéré comme une stratégie non-pharmacologique efficace pour le traitement du risque athérogène généré par l’obésité / The prevalence of obesity is increasing at an alarming rate in the western countries. It has been attributed to sedentariness and abundance of unhealthy food. Obesity is often associated with endothelial dysfunction and a high atherogenic risk. Several clinical investigations have reported that life style modification included physical exercise and the adoption of healthydiet was an efficient strategy to combat cardiovascular complications linked to obesity. However, numerous mechanisms by which exercise exerts the direct therapeutic effect on atherogenic risk linked to obesity are still unknown. Using the experimental model of high fat diet-induced obesity rat, the general aim of this study, was to identify the possible molecularmechanisms through which exercise with or without diet modification (high fat to standard diet) exerts an antiatherogenic action. Our results show that exercise independently of diet used, corrected the endothelial dysfunction induced by obesity. This benefit effect was associated with the decreased vascular oxidative stress. In effect, our results show that exercise alone was able to decrease NADPH oxidase activity in aortic tissue. Furthermore, we show for the first time that exercise, independently diet used, was able to modulate the translocation of p47phox subunit to membrane (which plays a pivotal role in NADPH oxidase activation). Ours results show also, that exercise with or without diet modification improves the Akt/eNOS phosphorylation pathway, suggesting that exercise increases NO production. In summary, exercise training even without diet modification, may be a non-pharmacological strategy treatment for atherogenic risk linked to obesity

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