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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.
301

Le rôle de la dysrégulation du métabolisme du cholestérol par le retrait des estrogènes sur la stéatose hépatique

Côté, Isabelle 12 1900 (has links)
Les estrogènes confèrent aux femmes une protection cardiovasculaire jusqu’à la ménopause. En effet, la perte des fonctions ovariennes engendre plusieurs désordres du profil lipidique qui s’accompagnent d’une accumulation de triglycérides au foie appelée stéatose hépatique. Le retrait des estrogènes perturbe de nombreuses voies de contrôle de la cholestérolémie, provoquant simultanément une hypercholestérolémie et une stéatose hépatiques. Toutefois, à ce jour, les mécanismes d’action du retrait des estrogènes sur le métabolisme du cholestérol favorisant le stockage de triglycérides au foie demeurent imprécis. À cet égard, les travaux de cette thèse visaient à clarifier l’ensemble des effets du retrait des estrogènes sur le métabolisme du cholestérol pouvant mener à la pathogenèse de la stéatose hépatique. Lors de la première étude, l’ovariectomie (Ovx) chez la rate, un modèle bien établi de la stéatose, avait permis d’identifier la voie d’assemblage des lipoprotéines à très faible densité (VLDL) comme élément contributif à la stéatose. La voie des VLDL reliant étant également une voie de transport du cholestérol, l’étude suivante a été réalisée afin de comprendre le rôle du cholestérol alimentaire sur les lipides hépatiques. Dans cette deuxième étude, le modèle de la diète riche en lipides et en cholestérol (HFHC), aussi reconnu pour induire une stéatose hépatique, a permis d’établir des liens étroits entre le métabolisme du cholestérol et celui des lipides hépatiques. Étonnamment, de manière similaire à l’Ovx, la diète HFHC perturbait la voie d’assemblage des VLDL. En outre, les données recueillies au cours de ces travaux indiquaient qu’une dysrégulation du métabolisme des acides biliaires avait contribué à la sévérité de la stéatose hépatique induite par cette diète HFHC. Dans la continuité de ces deux premiers projets, nous nous sommes intéressés aux effets concomitants du retrait des estrogènes et d’une diète HFHC sur la stéatose hépatique. De manière intéressante, lorsque combinés, l’Ovx et la diète HFHC potentialisaient non seulement l’accumulation de lipides hépatiques, mais également les perturbations moléculaires des voies sous-jacentes à la stéatose, dont l’assemblage des VLDL et de la sécrétion d’acides biliaires. Dans l’ensemble, les données présentées dans la revue de littérature et dans les trois études reliées à cette thèse indiquent qu’une dysrégulation du métabolisme du cholestérol en réponse au retrait des estrogènes entraîne des complications favorisant l’accumulation de lipides dans le foie. / Estrogens confer to women a cardiovascular protection until menopause. Indeed, the loss of ovarian functions leads to several lipid disorders along with hepatic triglycerides accumulation called hepatic steatosis. Estrogen withdrawal disrupts several cholesterol metabolism pathways that results in both hypercholesterolemia and hepatic steatosis. However, to date, the precise mechanisms by which estrogen withdrawal affect cholesterol metabolism pathways that favour lipid storage in the liver are unclear. In this regard, works in the present thesis aimed at elucidate the effects of estrogen withdrawal on cholesterol metabolism involved in hepatic steatosis pathogenesis. In the first study, estrogen withdrawal by ovariectomy (Ovx), a well established model for hepatic steatosis and hypercholesterolemia, had enabled the identification of very low density lipoprotein (VLDL) pathway as a contributory element for hepatic steatosis. Since the VLDL pathway relates lipids and cholesterol metabolism, we conducted the second study to explore the role of dietary cholesterol on hepatic lipids. In the second study, the high fat/high cholesterol (HFHC) diet, also recognized as a model for hepatic steatosis development, was used to explore links between cholesterol metabolism and hepatic fat accumulation. Surprisingly, HFHC diet also disrupted the VLDL pathway. Additionally, data provided in this study indicated that a dysregulation of bile acids metabolism might have contributed to the severity of hepatic steatosis induced by the HFHC diet. As a continuation of these projects, we were interested in the concomitant effects of estrogen withdrawal and HFHC diet on hepatic lipid accretion. Interestingly, when combined, Ovx and HFHC diet not only potentiated hepatic lipid accumulation but also molecular disruptions involved in underlying pathways for hepatic steatosis including the VLDL pathway and bile acid secretion. Overall, data presented in the review of litterature and provided by the three studies related to the present thesis indicate that cholesterol metabolism dysregulation following estrogen withdrawal result in complications that favour hepatic lipid accumulation.
302

Caractérisation thermique de matériaux isolants légers. Application à des aérogels de faible poids moléculaire / Thermal characterization of low density insulating materials.Application to low molecular weight aerogels

Félix, Vincent 24 November 2011 (has links)
La problématique de la sauvegarde de l’énergie pose un certain nombre de défis à la science, en particulier celui de son efficacité. La conception et la caractérisation de nouveaux matériaux isolants thermiques plus performants se révèlent donc fondamentales dans cette perspective. Les aérogels se présentent comme de sérieux candidats dans ce domaine, leur procédé de fabrication confère à certains d’entre eux des caractéristiques extrêmes telles qu’une grande porosité et une faible masse volumique. La caractérisation thermique de tels matériaux est délicate, leur faible sensibilité aux flux thermiques qui les traversent rend les méthodes connues difficiles à mettre en œuvre. A travers l’étude d’échantillons d’aérogels de faible poids moléculaire conçus au LCPM, une méthode de caractérisation adaptée a été développée. Cette méthode de type « tri-couche » offre les avantages d’être robuste et de s’affranchir de la connaissance de paramètres difficiles à atteindre dans de tels cas. La description et la validation de cette méthode sont l’objet principal de ce travail. Par ailleurs, les mesures de conductivité thermique sous vide ont été exploitées et ont permis une compréhension plus poussée de la structure de ces aérogels. Les résultats obtenus dans cette étude ouvrent donc des perspectives en vue de l’optimisation de nouvelles solutions pour l’isolation thermique / The issue of preserving energy raises a number of challenges to science, particularly its efficiency. The conception and characterization of new more efficient thermal insulating materials prove fundamental in this regard. Aerogels appear as serious candidates in this area, their manufacturing process provides extreme characteristics such as high porosity and low density for some of them. Thermal characterization of such materials is tricky, their low sensitivity to heat flux makes well-known methods difficult to implement. Through the study of low molecular weight aerogel samples designed by the LCPM a characterization method suitable to these samples has been developed by the LEMTA. This “three-layers” method offers the advantages of being robust and to overcome the knowledge of parameters that are difficult to reach in such cases. Describing and validating this method is the main object of this work. In addition, thermal conductivity measurements under vacuum have been processed which allowed a deeper understanding of the structure of aerogels. The results obtained this study open perspectives for the optimization of new solutions for thermal insulation
303

Efeitos do LDL oxidado em macrófagos M2. Implicações na aterosclerose. / Effects of oxidized LDL in M2 macrophages. Implications in atherosclerosis

Gonçalves, Fernanda Magalhães 12 September 2017 (has links)
A aterosclerose é uma doença crônica onde duas características marcantes são observadas: retenção de lipídios e inflamação. Compreender as interações entre as células do sistema imunológico e as lipoproteínas envolvidas na aterogênese são desafios urgentes, uma vez que as doenças cardiovasculares são a principal causa de morte no mundo. Os macrófagos são cruciais para o desenvolvimento de placas ateroscleróticas e para a perpetuação da inflamação em tais lesões; estas células também estão diretamente envolvidas na ruptura de placa instável. Recentemente diferentes populações de macrófagos estão sendo identificadas nas lesões ateroscleróticas. Embora macrófagos M2 tenham sido identificados, a função destas células na aterosclerose ainda não está definida. Neste projeto, avaliamos se a adição de LDLox altera a função de macrófagos M2. Resultados: 1- Foi possível observar que os M2 se mantem viáveis após o estímulo com as lipoproteínas. 2- Quando avaliamos a expressão de moléculas co-estimulatórias, receptores Scavenger, lectinas e integrinas na superfície das células, observamos que a adição de LDLn ou LDLox em 2 concentrações diferentes (5 e 50ug/ml), por diferentes períodos de tempo não alterou a expressão de nenhum dos marcadores avaliados. A presença de LDL também não alterou outra função primordial dos M2, a capacidade de fagocitose. 3- Quando investigamos a presença de citocinas no sobrenadante das culturas estimuladas ou não com as lipoproteínas, identificamos um aumento na secreção de IL-8, uma citocina pró-inflamatória, na presença de LDLox, semelhante ao observado com a população de macrófagos M1. 4- Avaliamos se os macrófagos M2 estimulados ou não com LDL mantem sua capacidade de favorecer a angiogênese. Observamos que nas culturas estimuladas com o sobrenadante das culturas dos M2 mantidos na presença de LDLox houve uma inibição significativa da formação de túbulos pelas HUVECs. 5- Observamos que na presença do meio condicionado dos M2 estimulados com LDLox ocorreu uma intensa degradação dos filamentos de matriz extracelular produzida por MEFs. 6- Avaliamos a expressão gênica de componentes de matriz, membrana basal, moléculas de adesão, proteases e também inibidores de protease nestas células. Dos 96 genes avaliados, observamos que a adição de LDLox reduziu a expressão de 10 genes de maneira significativa, entre eles: beta-Actina (ACTB), Colágeno 6A2 (Col6A2), Integrina alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), molécula de adesão celular endotelial plaquetária (PECAM) e Inibidor de metalopeptidase 2 (TIMP2). A adição de LDLox aumentou significativamente somente a expressão de trombospondina (TSP1). A adição de LDLn não alterou a expressão de nenhum gene de forma significativa. 7- A adição de LDLox induziu aumento da expressão da TSP1 e redução da expressão de colágeno 6, quando comparadas aos macrófagos M2 sem estímulo. Nossos resultados indicam que a adição de LDLox altera diversas funções dos macrófagos M2 in vitro. Em especial detectamos uma inibição significativa na angiogênese e também a secreção de mediadores que induzem a degradação da matriz extracelular. A adição de LDLox também inibiu a expressão de genes envolvidos com a estabilização da matriz extracelular. Nossos resultados sugerem que esta população de células pode contribuir para a perpetuação do processo inflamatório e degradação tecidual observados na lesão dos pacientes. Assim, acreditamos que este projeto contribuiu para o esclarecimento da participação dos M2 na patologia da aterosclerose / Atherosclerosis is a chronic disease where two key characteristics are observed: lipid retention and inflammation. Understanding the interactions between the cells of the immune system and the lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death in the world. Macrophages are crucial for the development of atherosclerotic plaques and for the inflammation in such lesions; These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although M2 macrophages has been identified, the function of these cells in atherosclerosis has not yet been defined. This project, we evaluated whether the addition of OxLDL alters the function of M2 macrophages. Results: 1- M2 macrophages remain viable after stimulation with the lipoproteins. 2- When evaluated the expression of co-stimulatory molecules, Scavenger receptors, lectins and integrins on the surface of the cells. We observed that the addition of LDLn or OxLDL at 2 different concentrations (5 and 50 ?g / ml) for different time periods did not alter the expression of any of the evaluated markers. 3- The presence of LDL also did not alter other primordial function of M2 cells, phagocytosis. 4- Was observed that cultures stimulated with conditioned medium of OxLDL-stimulated M2 there was a significant inhibition of tubule formation by HUVECs. 5- We observed that in the presence of OxLDL-stimulated M2 cells conditioned médium an intense degradation of the matrix filaments occurred. 6- We evaluated the gene expression of matrix components, basement membrane, adhesion molecules, proteases and also protease inhibitors in these cells. Of the 96 evaluated genes, we observed that the addition of OxLDL significantly reduced the expression of 10 genes, among them: Actin-beta (ACTB), Collagen 6A2 (Col6A2), Integrin alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), Platelet endothelial cell adhesion molecule (PECAM) and metallopeptidase 2 inhibitor (TIMP2). The addition of OxLDL significantly increased only the expression, thrombospondin-1 (TSP1). Addition of LDLn did not significantly alter the expression of any gene. 7- That OxLDL addition induced increased TSP1 expression and reduced collagen 6 expression, when compared to M2 macrophages without stimulation. Our results indicate that the addition of OxLDL alters several M2 macrophages functions in vitro. In particular we detected a significant inhibition in angiogenesis and also the secretion of mediators that induce the degradation of the extracellular matrix. The addition of OxLDL also inhibited the expression of genes involved in extracellular matrix stabilization. Our results suggest that this cell population may contribute to the perpetuation of the inflammatory process and tissue degradation observed in the lesion of the patients. Thus, we believe that this project contributed to better understand the participation of M2 in the pathology of atherosclerosis
304

Estudo da atividade e polimorfismos da Paraoxonase-1 em indivíduos infectados pelo vírus da imunodeficiência humana tipo-1 (HIV-1) tratados com inibidores de protease / Study of activity and polymorphisms of Paraoxonase-1 in individuals infected with human immunodeficiency vírus type-1 (HIV-1) treated with protease inhibitors

Cunha, Joel da 31 August 2012 (has links)
A enzima Paraoxonase-1 (PON1) possui atividades paraoxonase, arilestearase e lactonase, entre outras. É a mais estuda da família das PONs que é composta pela PON1, PON2 e PON3. Sugere-se, que todas atuam inibindo o processo de peroxidação lipídica de moléculas como a lipoproteína de baixa densidade (LDL) e alta densidade (HDL), caracterizando assim um possível papel anti-aterogênico. O gene da PON1 apresenta dois sítios polimórficos, com a troca de uma Gln192Arg (Q/R) e Met55Leu, que estão associados com diferenças na atividade e concentrações séricas da enzima. Por sua vez, indivíduos soropositivos para o HIV-1 apresentam alterações do metabolismo lipídico, que poderiam estar associados a alterações na atividade da PON1 e a terapia antirretroviral (TARV) com inibidores de protease (IP). O objetivo do estudo foi determinar as atividades séricas da PON1 e da arilestearase (ARE), e as freqüências alélicas dos polimorfismos genéticos da PON1 192QR e 55LM, e ainda, avaliar a correlação destes parâmetros com as alterações lipídicas em indivíduos soropositivos para o HIV-1 tratados com IP. No período de Setembro de 2009 até Junho de 2012, 174 indivíduos soropositivos e 46 soronegativos para o HIV-1 foram estudados. Foi realizada a genotipagem dos polimorfismos da PON1 192QR e 55LM através de PCR-RFLP. A atividade sérica da PON1/ARE foi avaliada por espectrofotometria empregando-se como substratos o paraoxon e o fenilacetato, respectivamente. O RNA-HIV-1 foi quantificado pelo método NASBA, e os linfócitos T-CD4+ e T-CD8+ por citometria de fluxo. Os níveis séricos de colesterol total, HDL, LDL, triglicérides (TG), ApoA1 e ApoB100 foram determinados e os anticorpos IgG anti-oxLDL por ELISA. A atividade sérica da PON1 foi inferior nos grupos de soropositivos, p<0,05, porém, a atividade ARE não apresentou diferenças entre os grupos estudados, p>0,05. Ambas as atividades não apresentaram relação com os genótipos PON1 192QR e 55LM, e estes genótipos apresentaram uma freqüência alélica semelhante ao grupo de soronegativos. Os níveis séricos de TG foram superiores nos grupos de soropositivos com TARV, p<0,05, enquanto o grupo tratado com IP apresentou níveis séricos de HDL e Apo-A1 inferiores aos demais grupos, p<0,05. Níveis séricos de Apo-B100, IgG anti-oxLDL, e o índice de risco aterogênico foram superiores no grupo tratado com IP, p<0,05. Concluí-se, que indivíduos soropositivos para o HIV-1 apresentaram alterações no metabolismo lipídico, principalmente nos tratados com IP, que adicionalmente apresentaram um maior índice de risco aterogênico e maiores níveis de anticorpos IgG anti-oxLDL. Estas alterações não apresentaram relação com os polimorfismos PON1 192QR e 55LM da PON1, e demonstraram que a atividade da enzima PON-1 esta diminuída em indivíduos soropositivos para o HIV-1 / The enzyme Paraoxonase-1 (PON1) has paraoxonase (PON), arylesterase (ARE) and lactonase activities, among others. It is the most studied member of PON family which is composed of PON1, PON2 and PON3. It is suggested that all members acts by inhibiting the peroxidation of lipid molecules as the low-density lipoprotein (LDL) and high-density lipoprotein (HDL), characterizing a potential anti-atherogenic effect. The PON1 gene has two mainly polymorphic sites, with an exchange of Gln192Arg (Q/R) and Met55Leu (L/M), which are associated with differences in activity and serum concentrations of the enzyme. In turn, seropositive individuals for HIV-1 show changes in lipid metabolism, which could be associated with changes in the activity of PON1 and highly active antiretroviral therapy (HAART) with protease inhibitors (PI). The aim of this study was to determinate the serum PON and ARE activities of PON1, the allele frequencies of PON1 192QR and PON1 55LM genetic polymorphisms and evaluate the correlation between these parameters and lipid abnormalities in seropositive patients for HIV-1 treated with IP. In the period from September 2009 until June 2012, 174 seropositive individuals and 46 soronegative individuals for HIV-1 were studied. We performed PON1 192QR and 55LM genotyping by PCR-RFLP. Serum activities PON and ARE of PON1 were evaluated by spectrophotometry using paraoxon and phenylacetate, respectively, as substrates. The HIV-1-RNA was quantified by the NASBA method, and lymphocytes T-CD4+ and T-CD8+, by flow cytometry. Serum levels of total cholesterol, HDL, LDL, triglycerides (TG), apoA1 and ApoB100 were determined. IgG anti-oxLDL antibodies were quantified by ELISA. The serum PON1 activity was lower in the seropositive group, p<0.05, however, ARE activity did not differ between groups, p>0.05. Both activities had no relation with the PON1 192QR and PON1 55LM genotype, and these individuals showed an allele frequency similar to the seronegative group. Serum levels of TG were higher in groups of HIV-positive with HAART, p<0.05, while the IP-treated group showed serum levels of HDL and ApoA1 lower than other groups, p <0.05. Serum levels of ApoB100, IgG anti-oxLDL antibodies, and atherogenic risk indices were higher in the group treated with PI, p<0.05. It was concluded that individuals HIV-1-infected showed changes in lipid metabolism, especially in those treated with IP, which additionally showed a higher rate of atherogenic risk and higher levels of IgG anti-oxLDL antibodies. These changes did not correlated with PON1 192QR and 55LM polymorphisms and demonstrated that the activity of PON1enzyme is decreased in individuals seropositive for HIV-1
305

Mapeamento de bits para adaptação rápida a variações de canal de sistemas QAM codificados com LDPC

CORRÊA, Fernanda Regina Smith Neves 29 September 2017 (has links)
Submitted by Carmen Torres (carmensct@globo.com) on 2018-02-09T18:11:30Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MapeamentoBitsAdaptacao.pdf: 986310 bytes, checksum: 6e1b30f6ca34fc67df43f3141680c73a (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2018-02-16T16:12:49Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MapeamentoBitsAdaptacao.pdf: 986310 bytes, checksum: 6e1b30f6ca34fc67df43f3141680c73a (MD5) / Made available in DSpace on 2018-02-16T16:12:49Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese_MapeamentoBitsAdaptacao.pdf: 986310 bytes, checksum: 6e1b30f6ca34fc67df43f3141680c73a (MD5) Previous issue date: 2017-09-29 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os codigos com matriz de vericação de paridade de baixa densidade (LDPC) tem sido adotados como estrategia de correção de erros em diversos padrões de sistemas de comunicação, como nos sistemas G.hn (padrão que unifica as redes domesticas) e IEEE 802.11n (padrão para redes sem o locais). Nestes sistemas com modulação de amplitude em quadratura (QAM) codicados com LDPC, mapear propriamente os bits codificados para os diferentes sub-canais, considerando o fato de os sub-canais terem diferentes qualidades, garante uma melhora no desempenho geral do sistema. Nesse sentido, esta Tese apresenta uma nova técnica de mapeamento de bits, baseada na suposição de que bits transmitidos em sub-canais \bons" ajudam bits transmitidos em sub-canais \ruins". Isto e possível através de algumas restrições impostas ao grafo de Tanner associado, semelhantes aos códigos Root-LDPC. A otimização deste mapeamento de bits utilizando curvas de transferência de informação extrínseca (EXIT charts) também e apresentada. Observa-se que esse mapeamento tem a vantagem de um espaço de busca de otimização reduzido quando aplicado ao sistema com modo de transmissão de portadora única. Além disso, em situações nas quais o espaço de busca não e tão reduzido, como em aplicações baseadas em multiplexação por divisão de frequência ortogonal (OFDM), chegou-se a uma simples regra pratica associada as restrições do mapeamento de bits que praticamente elimina a necessidade de uma otimização. Por fim, um estudo do impacto do nível de desequilíbrio de contabilidade através dos sub-canais sobre o desempenho do mapeamento de bits e apresentado. Os resultados das simulações mostram que a estratégia de mapeamento de bits melhora o desempenho do sistema, e que, na presença de variações do canal, o sistema pode, adaptativamente, aplicar um novo mapeamento de bits sem a necessidade de recorrer a uma otimização complexa, podendo ser muito útil em sistemas práticos. / Low-Density parity-check (LDPC) codes are being adopted as the error correction strategy in di erent system standards, such as the G.hn (home networking standard) and the IEEE 802.11n (wireless local standard). In these LDPC-coded quadrature amplitude modulation (QAM) systems, mapping the LDPC coded bits properly to the di erent sub-channels considering the fact that sub-channels have di erent qualities ensures an improved overall system performance. Accordingly, this thesis presents a new bit mapping technique based on the assumption that bits transmitted in \good" sub-channels, help bits transmitted in \bad" sub-channels. This can be made possible through some restrictions to be imposed on the associated Tanner graph, akin to Root-LDPC codes. An optimization of the root-like bit mapping through extrinsic information transfer (EXIT) charts analysis is also presented. We show that this mapping has the advantage of a reduced optimization search space when applied to single-carrier based systems. Moreover, in situations where the search space is not só reduced, such as in orthogonal frequency division multiplexing (OFDM)-based applications, we arrive at a rule of thumb associated with the bit mapping constraints that practically eliminates the need for an optimization. Finally, a study of the impact of the level of reliability imbalance across the sub-channels on the performance of the root-like bit mapping is presented. Simulation results show that the new bit mapping strategy improves performance, and that in the presence of channel variations, the system can, adaptively, apply a new bit mapping without the need of a complex optimization, which can be very useful in practical systems.
306

Biomarcadores de risco cardiovascular em pacientes HIV positivos tratados e não tratados com terapia antirretroviral / Biomarkers of cardiovascular risk in HIV-positive patients treated and untreated with antiretroviral therapy.

Cicarelli, Luciane Marzzullo 30 September 2016 (has links)
No advento dos antirretrovirais potentes, os indivíduos infectados pelo vírus da imunodeficiência humana (HIV) começaram a apresentar risco maior para o desenvolvimento de doença cardiovascular (DCV). Este aumento do risco cardiovascular pode ser associado tanto à infecção viral quanto ao tratamento antirretroviral (TARV), que provocam mudanças pró-aterogênicas como o aumento do colesterol total e da lipoproteína de baixa densidade (LDL), além da diminuição da lipoproteína de alta densidade (HDL). A ativação imune e as alterações lipídicas são mecanismos associados com a infecção pelo HIV e com o risco de DCV. Este trabalho utilizou ensaios imunoenzimáticos para a determinação plasmática de biomarcadores emergentes de risco cardiovascular relacionados com modificações da lipoproteína de baixa densidade, a saber: LDL eletronegativa [LDL(-)] e formas oxidadas da LDL, ou seja, LDL-oxi (resíduos lisina da apolipoproteína B100 modificados com malondialdeído), LDL-HNE (resíduos lisina da ApoB100 modificados com 4-hidroxinonenal) e LDL-CML (resíduos lisina da ApoB100 modificados por carboximetila), além de biomarcadores relacionados com a resposta imune-inflamatória, ou seja, autoanticorpos IgG e IgM anti-LDL(-), imunocomplexo de LDL(-) [IC-LDL(-)], proteína amiloide sérica A (SAA) e mieloperoxidase (MPO). Também foram determinadas as concentrações séricas dos biomarcadores de risco relacionados às apolipoproteínas: apolipoproteína A-I (ApoA-I), apolipoproteína B (ApoB) e apolipoproteína E (ApoE). A população estudada incluiu indivíduos com infecção pelo HIV, tratados (HIV-TARV) e não tratados (HIV-NT) com terapia antirretroviral e indivíduos sem infecção pelo HIV (controle). Não foram identificadas diferenças para as concentrações de LDL(-), IC-LDL(-), anti- LDL(-)-IgM, SAA, ApoA-I, ApoB e ApoE entre os grupos estudados (HIV-TARV, HIV-NT e controle). A ApoA-I correlacionou-se positivamente com ApoB e ApoE (rs= 0,418 e rs= 0,347, Spearman, p<0,01) e a ApoB com a ApoE (rs= 0,286, Spearman, p<0,01). Verificou-se correlação inversa entre as concentrações de LDL(-) e IC-LDL(-) (rs= -0,214, Spearman, p<0,05). Os níveis de anti-LDL(-)-IgG correlacionaram-se positivamente com IC-LDL(-) e anti-LDL(-)-IgM (rs= 0,240, Spearman, p<0,05 e rs= 0,348, Spearman, p<0,01). As concentrações de LDL-CML correlacionaram-se positivamente com LDL(-), LDL-oxi, LDL-HNE e IC-LDL(-) (rs= 0,212, Spearman, p<0,05; rs= 0,214, Spearman, p<0,05; rs= 0,573, Spearman, p<0,01 e rs= 0,219, Spearman, p<0,05). O grupo HIV-NT apresentou níveis mais elevados de anticorpos anti-LDL(-)-IgG comparado ao grupo controle (Kruskal-Wallis, p<0,01). Em contraste, observou-se no grupo HIV-NT diminuição das concentrações de MPO, LDL-HNE e LDL-CML em relação ao grupo controle (Kruskal-Wallis, p<0,01). A comparação dos grupos HIV-NT e HIV-TARV demonstrou que o TARV promoveu diminuição das concentrações dos anticorpos anti-LDL(-)-IgG e aumentou os níveis de LDL-oxi (Kruskal-Wallis, p<0,01). O grupo HIV-TARV apresentou aumento das concentrações de LDL-oxi e diminuição dos níveis de MPO, LDL-HNE e LDL-CML em relação ao controle (Kruskal-Wallis, p<0,01). Em conclusão, a infecção pelo HIV modificou o biomarcador de inflamação MPO e o perfil de biomarcadores relacionados às modificações da LDL (menor formação de LDL-HNE e LDL-CML), além aumentar a resposta imune-humoral à LDL eletronegativa [anti-LDL(-)-IgG], enquanto o tratamento com antirretrovirais inibiu esta resposta. Os outros biomarcadores estudados não foram modificados pela infecção viral ou pelo tratamento antirretroviral. / In the advent of potent antiretroviral therapy, individuals infected with human immunodeficiency virus (HIV) have showed an increased risk for developing cardiovascular disease (DCV). Studies have discussed that the increased risk may be related to both the disease and antiretroviral treatment (TARV), that produced pro-atherogenic changes such as increased of total cholesterol and low density lipoprotein (LDL) and decreased high density lipoprotein. The immune activation and the lipid modifications are well known mechanisms related to HIV infection and the risk of DCV. This study used immunoassays for plasma quantification for emerging biomarkers of cardiovascular risk related to modification of low density lipoprotein: electronegative LDL [LDL(-)] and oxidized forms of LDL, LDL-oxi (lysine residues of apolipoprotein B100 modified by malondialdehyde), LDL-HNE (lysine residues of ApoB100 modified by 4-hydroxynonenal) and LDL-CML (lysine residues of ApoB100 modified by carboxymethyl) and biomarkers associated to immune and inflammatory responses, IgG and IgM autoantibodies anti-LDL(-) and immunecomplexe of LDL(-) [IC-LDL(-)], serum amyloid A protein (SAA) and myeloperoxidase (MPO). Also, were determined serum concentrations of risk biomarkers related to apolipoproteins: apolipoprotein A-I (ApoA-I), apolipoprotein B (ApoB) and apolipoprotein E (ApoE). The studied population included patients with HIV infection, treated (HIV-TARV) and untreated (HIV-NT) with antiretroviral therapy and individuals without HIV infection (controle). No differences were identified for concentrations of LDL(-), ICLDL(-), anti-LDL(-)-IgM, SAA, ApoA-I, ApoB and ApoE between studied groups (HIV-TARV, HIV-NT and controle). The ApoA-I was positively correlated to ApoB and ApoE (rs= 0,418 e rs= 0,347, Spearman, p<0,01) and ApoB to ApoE (rs= 0,286, Spearman, p<0,01). There was an inverted correlation between LDL(-) and IC-LDL(-) (rs= -0.214, Spearman, p<0,05). The levels of anti-LDL(-)-IgG were positively correlated to IC-LDL(-) and antibodies anti-LDL(-)-IgM (rs= 0.240; Spearman; p <0.05 and rs= 0.348; Spearman; p <0.01). The concentrations of LDL-CML were positively correlated to LDL(-), LDL-oxi, LDL-HNE e IC-LDL(-) (rs= 0,212, Spearman, p<0,05; rs= 0,214, Spearman, p<0,05; rs= 0,573, Spearman, p<0,01 e rs= 0,219, Spearman, p<0,05). The HIV-NT group showed higher levels of anti-LDL(-)-IgG compared to Control group (Kruskal-Wallis, p<0,01). In contrast, was observed lower levels for HIV-NT group to MPO, LDL-HNE and LDL-CML when compared to Control group (Kruskal-Wallis, p<0,01). The comparison of HIV-NT and HIV-TARV groups demonstrated that TARV caused a decrease of concentrations of anti-LDL(-)-IgG antibodies and an increased of LDL-oxi levels (Kruskal-Wallis, p <0.01). The HIV-TARV group showed increased LDL-oxi concentrations and decreased at levels of MPO, LDL-HNE e LDL-CML when compared to Control (Kruskal-Wallis, p<0,01). In conclusion, the HIV infection changed the biomarker of inflammation MPO and the profile of biomarkers related to modifications of LDL (lower concentrations of LDL-HNE and LDL-CML), as well as increased the humoral-immune response to electronegative LDL [anti-LDL(-)-IgG], while treatment with antiretroviral therapy inhibited this response. The other studied biomarkers were not modified either by viral infection or antiretroviral treatment.
307

Effect of oxidized LDL and oxidized cholesterol on cardiovascular system.

January 2005 (has links)
Ng Chi Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 147-160). / Abstracts in English and Chinese. / ACKNOWLEDGMENTS --- p.I / ABSTRACT --- p.II / LIST OF ABBREVIATIONS --- p.VII / TABLE OF CONTENTS --- p.IX / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter 1.1 --- Introduction of Low-density lipoprotein --- p.1 / Chapter 1.1.1 --- What are lipids? --- p.1 / Chapter 1.1.2 --- Function and structure of cholesterol --- p.1 / Chapter 1.1.3 --- Function and classification of lipoprotein --- p.1 / Chapter 1.2 --- Functions of low-density lipoprotein --- p.2 / Chapter 1.3 --- Basic structure of low-density lipoprotein --- p.4 / Chapter 1.4 --- Principle on isolation and purification of low-density lipoprotein --- p.4 / Chapter 1.5 --- Cholesterol transport system --- p.7 / Chapter 1.5.1 --- Exogenous pathway of cholesterol metabolism --- p.7 / Chapter 1.5.2 --- Endogenous pathway of cholesterol metabolism --- p.7 / Chapter 1.5.3 --- Reverse transport of Cholesterol --- p.8 / Chapter 1.6 --- Oxidation of LDL --- p.10 / Chapter 1.6.1 --- Agents that causes oxidation --- p.10 / Chapter 1.6.1.1 --- Lipoxygenases --- p.10 / Chapter 1.6.1.2 --- Myeloperoxidase --- p.10 / Chapter 1.6.1.3 --- Reactive nitrogen species --- p.11 / Chapter 1.6.1.4 --- Reactive oxygen species --- p.11 / Chapter 1.6.2 --- Factors that affect the susceptibility of LDL oxidation --- p.13 / Chapter 1.7 --- Hyperlipidaemia 一 chance to increase LDL oxidation --- p.13 / Chapter 1.7.1 --- Definition of hyperlipidemia and hypercholesterolemia --- p.13 / Chapter 1.7.2 --- Risk factors of hyperlipidaemia --- p.13 / Chapter 1.7.2.1 --- High fat low fibre diets: --- p.13 / Chapter 1.7.2.2 --- Obesity --- p.14 / Chapter 1.7.2.3 --- Type II diabetes --- p.14 / Chapter 1.7.2.4 --- Genetic factors (Familial hyperlipidemias) --- p.14 / Chapter 1.8 --- Diseases related to oxidized LDL --- p.15 / Chapter 1.8.1 --- Cardiovascular diseases --- p.15 / Chapter 1.8.1.1 --- Atherosclerosis and ischemic heart attack --- p.15 / Chapter 1.8.1.2 --- Factors that affect incidence of atherosclerosis --- p.16 / Chapter 1.8.1.2.1 --- Triglyceride-rich lipoprotein --- p.16 / Chapter 1.8.1.2.2 --- Small and dense LDL --- p.16 / Chapter 1.8.1.3 --- Stroke --- p.17 / Chapter 1.8.2 --- Common ways to reduce plasma cholesterol level --- p.17 / Chapter 1.8.2.1 --- Diet control --- p.17 / Chapter 1.8.2.2 --- Physical activity --- p.17 / Chapter 1.8.2.3 --- Drug therapy --- p.18 / Chapter CHAPTER 2 --- IMPAIRMENT OF OXIDIZED LDL ON ENDOTHELIUM-DEPENDENT RELAXATION / Chapter 2.1 --- Introduction --- p.19 / Chapter 2.1.1 --- Properties and function of phenylephrine hydrochloride --- p.22 / Chapter 2.1.2 --- Properties and function of acetylcholine --- p.22 / Chapter 2.2 --- Objectives --- p.23 / Chapter 2.3 --- Materials and methods --- p.24 / Chapter 2.3.1 --- Preparation of drugs --- p.24 / Chapter 2.3.2 --- Preparation of human native LDL --- p.25 / Chapter 2.3.3 --- Preparation of oxidized LDL --- p.27 / Chapter 2.3.4 --- Preparation of aorta --- p.27 / Chapter 2.3.5 --- Measurement of Isometric Force in vitro --- p.30 / Chapter 2.3.5.1 --- Protocol 1- Dose effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.30 / Chapter 2.3.5.2 --- Protocol 2 - Time effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.30 / Chapter 2.3.5.3 --- Protocol 3 - Effect of co-incubation of LDL and copper(ll) sulphate on acetylcholine-induced vasorelaxation --- p.31 / Chapter 2.3.5.4 --- Protocol 4 - Effect of oxidized LDL on selected vasodilators --- p.32 / Chapter 2.3.5.5 --- Protocol 5 - Effect of pretreatment of L-arginine on oxidized LDL impaired -endothelium-induced relaxation --- p.32 / Chapter 2.3.5.6 --- Protocol 6 - Effect of a -tocopherol on oxidized LDL-damaged acetylcholine- induced vasorelaxation --- p.33 / Chapter 2.3.5.7 --- Protocol 7 - Effect of a -tocopherol on LDL and copper(ll) sulphate- induced endothelial dysfunction --- p.33 / Chapter 2.3.6 --- Western blot analysis of endothelial nitric oxide synthase (eNOS) protein --- p.34 / Chapter 2.3.7 --- Statistics --- p.35 / Chapter 2.4 --- Results --- p.36 / Chapter 2.4.1 --- Dose effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.36 / Chapter 2.4.2 --- Time effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.36 / Chapter 2.4.3 --- Effect of co-incubation of LDL and copper(II) sulphate on acetylcholine- induced vasorelaxation --- p.39 / Chapter 2.4.4 --- Effect of oxidized LDL on selected vasodilators --- p.41 / Chapter 2.4.5 --- Effect of pretreatment of L-arginine on oxidized LDL impaired- acetylcholine-induced relaxation --- p.41 / Chapter 2.4.6 --- Effect of a-tocopherol on oxidized LDL-damaged acetylcholine- induced vasorelaxation --- p.48 / Chapter 2.4.7 --- Effect of a-tocopherol on LDL and copper(II) sulphate-induced endothelial dysfunction --- p.50 / Chapter 2.4.8 --- eNOS Protein expression --- p.50 / Chapter 2.5 --- Discussion --- p.53 / Chapter CHAPTER 3 --- EFFECTS OF LDL INJECTION ON THE ENDOTHELIAL FUNCTION OF RATS / Chapter 3.1 --- Introduction --- p.58 / Chapter 3.2 --- Objective --- p.60 / Chapter 3.3 --- Methods and Materials --- p.61 / Chapter 3.3.1 --- Preparation of Drugs --- p.61 / Chapter 3.3.2 --- Preparation of LDL --- p.61 / Chapter 3.3.3 --- Animal Treatment --- p.61 / Chapter 3.3.4 --- Serum lipid and lipoprotein determinations --- p.62 / Chapter 3.3.5 --- Measurement of serum MDA level by TBARS assay --- p.62 / Chapter 3.3.6 --- Preparation of aorta --- p.62 / Chapter 3.3.7 --- Organ bath experiment --- p.63 / Chapter 3.3.8 --- Statistics --- p.64 / Chapter 3.4 --- Result --- p.65 / Chapter 3.4.1 --- Growth and food intake --- p.65 / Chapter 3.4.2 --- "Effect of LDL injection on serum TC, TG and HDL-C" --- p.65 / Chapter 3.4.3 --- Effect of LDL injection on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.65 / Chapter 3.4.4 --- Serum MDA level --- p.68 / Chapter 3.4.5 --- Phenylephrine-induced contraction --- p.70 / Chapter 3.4.6 --- Endothelium-dependent and -independent relaxation --- p.75 / Chapter 3.5 --- Discussion --- p.79 / Chapter CHAPTER 4 --- EFFECTS OF INDIVIDUAL COMPONENT OF OXIDIZED LDL ON ENDOTHELIUM-DEPENDENT RELAXATION / Chapter 4.1 --- Introduction --- p.83 / Chapter 4.2 --- Objectives --- p.85 / Chapter 4.3 --- Materials and methods --- p.86 / Chapter 4.3.1 --- Preparation of drugs --- p.86 / Chapter 4.3.2 --- Preparation of human native LDL and oxidized LDL --- p.86 / Chapter 4.3.3 --- GC analysis of fatty acid composition in LDL --- p.86 / Chapter 4.3.4 --- TBARS assay analysis of MDA content in LDL --- p.87 / Chapter 4.3.5 --- GC analysis of cholesterol oxidation products in LDL --- p.89 / Chapter 4.3.6 --- Thin-layer chromatography analysis of LPC in LDL --- p.91 / Chapter 4.3.7 --- Preparation of aorta --- p.92 / Chapter 4.3.8 --- Measurement of Isometric Force in vitro --- p.92 / Chapter 4.3.8.1 --- Protocol 1- effect of LPC on acetylcholine-induced vasorelaxation --- p.92 / Chapter 4.3.8.2 --- Protocol 2- effect of cholesterol oxidation products on acetylcholine-induced vasorelaxation --- p.92 / Chapter 4.3.8.3 --- Protocol 3- effect of oxidized fatty acids on acetylcholine-induced vasorelaxation --- p.93 / Chapter 4.3.9 --- Statistics --- p.93 / Chapter 4.4 --- Results --- p.94 / Chapter 4.4.1 --- Compositional differences between native LDL and oxidized LDL.… --- p.94 / Chapter 4.4.2 --- Effect of LPC on endothelium-dependent relaxation --- p.98 / Chapter 4.4.3 --- Effect of COPs on endothelium-dependent relaxation --- p.98 / Chapter 4.4.4 --- Effect of oxidized fatty acids on endothelium-dependent relaxation --- p.101 / Chapter 4.5 --- Discussion --- p.103 / Chapter CHAPTER 5 --- EFFECTS OF DIETARY OXIDIZED CHOLESTEROL ON BLOOD CHOLESTEROL LEVEL IN HAMSTERS / Chapter 5.1 --- Introduction --- p.107 / Chapter 5.2 --- Objectives --- p.111 / Chapter 5.3 --- Materials and Methods --- p.112 / Chapter 5.3.1 --- Preparation of Oxidized Cholesterol --- p.112 / Chapter 5.3.2 --- Diet preparation --- p.112 / Chapter 5.3.3 --- Animals --- p.113 / Chapter 5.3.4 --- Serum lipid and lipoprotein determinations --- p.116 / Chapter 5.3.5 --- GC analysis of cholesterol and cholesterol oxidation products on organs --- p.116 / Chapter 5.3.6 --- Extraction of neutral and acidic sterols from fecal samples --- p.117 / Chapter 5.3.6.1 --- Determination of neutral sterols --- p.117 / Chapter 5.3.6.2 --- Determination of acidic sterols --- p.117 / Chapter 5.3.6.3 --- GLC analysis of neutral and acidic sterols --- p.118 / Chapter 5.3.7 --- Organ bath experiment --- p.121 / Chapter 5.3.7.1 --- Preparation of aorta --- p.121 / Chapter 5.3.7.2 --- Aortic relaxation --- p.121 / Chapter 5.3.8 --- Analysis of the total area of atherosclerotic plaque on aorta --- p.122 / Chapter 5.3.9 --- Statistics --- p.122 / Chapter 5.4 --- Results --- p.123 / Chapter 5.4.1 --- GC of oxidized cholesterol --- p.123 / Chapter 5.4.2 --- Growth and food intake --- p.123 / Chapter 5.4.3 --- "Effect of non-oxidized and oxidized cholesterol on serum TC, TG and HDL-C" --- p.123 / Chapter 5.4.4 --- Effect of non-oxidized and oxidized cholesterol on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.124 / Chapter 5.4.5 --- Effect ofnon-oxidized and oxidized cholesterol on concentration of hepatic cholesterol --- p.128 / Chapter 5.4.6 --- Effect of non-oxidized and oxidized cholesterol on concentration of cholesterol oxidation products accumulated in liver --- p.128 / Chapter 5.4.7 --- Effect of non-oxidized and oxidized cholesterol on concentration of brain and aortic cholesterol --- p.128 / Chapter 5.4.8 --- Effect of non-oxidized and oxidized cholesterol on fecal neutral and acidic sterols --- p.129 / Chapter 5.4.9 --- Effect of non-oxidized and oxidized cholesterol on aortic relaxation --- p.135 / Chapter 5.4.10 --- Effect of non-oxidzied and oxidized cholesterol on area of atherosclerotic plaque --- p.137 / Chapter 5.5 --- Discussion --- p.139 / Chapter CHAPTER 6 --- CONCLUSION --- p.143 / REFERENCES --- p.146
308

Efeitos do LDL oxidado em macrófagos M2. Implicações na aterosclerose. / Effects of oxidized LDL in M2 macrophages. Implications in atherosclerosis

Fernanda Magalhães Gonçalves 12 September 2017 (has links)
A aterosclerose é uma doença crônica onde duas características marcantes são observadas: retenção de lipídios e inflamação. Compreender as interações entre as células do sistema imunológico e as lipoproteínas envolvidas na aterogênese são desafios urgentes, uma vez que as doenças cardiovasculares são a principal causa de morte no mundo. Os macrófagos são cruciais para o desenvolvimento de placas ateroscleróticas e para a perpetuação da inflamação em tais lesões; estas células também estão diretamente envolvidas na ruptura de placa instável. Recentemente diferentes populações de macrófagos estão sendo identificadas nas lesões ateroscleróticas. Embora macrófagos M2 tenham sido identificados, a função destas células na aterosclerose ainda não está definida. Neste projeto, avaliamos se a adição de LDLox altera a função de macrófagos M2. Resultados: 1- Foi possível observar que os M2 se mantem viáveis após o estímulo com as lipoproteínas. 2- Quando avaliamos a expressão de moléculas co-estimulatórias, receptores Scavenger, lectinas e integrinas na superfície das células, observamos que a adição de LDLn ou LDLox em 2 concentrações diferentes (5 e 50ug/ml), por diferentes períodos de tempo não alterou a expressão de nenhum dos marcadores avaliados. A presença de LDL também não alterou outra função primordial dos M2, a capacidade de fagocitose. 3- Quando investigamos a presença de citocinas no sobrenadante das culturas estimuladas ou não com as lipoproteínas, identificamos um aumento na secreção de IL-8, uma citocina pró-inflamatória, na presença de LDLox, semelhante ao observado com a população de macrófagos M1. 4- Avaliamos se os macrófagos M2 estimulados ou não com LDL mantem sua capacidade de favorecer a angiogênese. Observamos que nas culturas estimuladas com o sobrenadante das culturas dos M2 mantidos na presença de LDLox houve uma inibição significativa da formação de túbulos pelas HUVECs. 5- Observamos que na presença do meio condicionado dos M2 estimulados com LDLox ocorreu uma intensa degradação dos filamentos de matriz extracelular produzida por MEFs. 6- Avaliamos a expressão gênica de componentes de matriz, membrana basal, moléculas de adesão, proteases e também inibidores de protease nestas células. Dos 96 genes avaliados, observamos que a adição de LDLox reduziu a expressão de 10 genes de maneira significativa, entre eles: beta-Actina (ACTB), Colágeno 6A2 (Col6A2), Integrina alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), molécula de adesão celular endotelial plaquetária (PECAM) e Inibidor de metalopeptidase 2 (TIMP2). A adição de LDLox aumentou significativamente somente a expressão de trombospondina (TSP1). A adição de LDLn não alterou a expressão de nenhum gene de forma significativa. 7- A adição de LDLox induziu aumento da expressão da TSP1 e redução da expressão de colágeno 6, quando comparadas aos macrófagos M2 sem estímulo. Nossos resultados indicam que a adição de LDLox altera diversas funções dos macrófagos M2 in vitro. Em especial detectamos uma inibição significativa na angiogênese e também a secreção de mediadores que induzem a degradação da matriz extracelular. A adição de LDLox também inibiu a expressão de genes envolvidos com a estabilização da matriz extracelular. Nossos resultados sugerem que esta população de células pode contribuir para a perpetuação do processo inflamatório e degradação tecidual observados na lesão dos pacientes. Assim, acreditamos que este projeto contribuiu para o esclarecimento da participação dos M2 na patologia da aterosclerose / Atherosclerosis is a chronic disease where two key characteristics are observed: lipid retention and inflammation. Understanding the interactions between the cells of the immune system and the lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death in the world. Macrophages are crucial for the development of atherosclerotic plaques and for the inflammation in such lesions; These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although M2 macrophages has been identified, the function of these cells in atherosclerosis has not yet been defined. This project, we evaluated whether the addition of OxLDL alters the function of M2 macrophages. Results: 1- M2 macrophages remain viable after stimulation with the lipoproteins. 2- When evaluated the expression of co-stimulatory molecules, Scavenger receptors, lectins and integrins on the surface of the cells. We observed that the addition of LDLn or OxLDL at 2 different concentrations (5 and 50 ?g / ml) for different time periods did not alter the expression of any of the evaluated markers. 3- The presence of LDL also did not alter other primordial function of M2 cells, phagocytosis. 4- Was observed that cultures stimulated with conditioned medium of OxLDL-stimulated M2 there was a significant inhibition of tubule formation by HUVECs. 5- We observed that in the presence of OxLDL-stimulated M2 cells conditioned médium an intense degradation of the matrix filaments occurred. 6- We evaluated the gene expression of matrix components, basement membrane, adhesion molecules, proteases and also protease inhibitors in these cells. Of the 96 evaluated genes, we observed that the addition of OxLDL significantly reduced the expression of 10 genes, among them: Actin-beta (ACTB), Collagen 6A2 (Col6A2), Integrin alfa 6 (ITGA6), Metaloproteinase 15 (MMP15), Platelet endothelial cell adhesion molecule (PECAM) and metallopeptidase 2 inhibitor (TIMP2). The addition of OxLDL significantly increased only the expression, thrombospondin-1 (TSP1). Addition of LDLn did not significantly alter the expression of any gene. 7- That OxLDL addition induced increased TSP1 expression and reduced collagen 6 expression, when compared to M2 macrophages without stimulation. Our results indicate that the addition of OxLDL alters several M2 macrophages functions in vitro. In particular we detected a significant inhibition in angiogenesis and also the secretion of mediators that induce the degradation of the extracellular matrix. The addition of OxLDL also inhibited the expression of genes involved in extracellular matrix stabilization. Our results suggest that this cell population may contribute to the perpetuation of the inflammatory process and tissue degradation observed in the lesion of the patients. Thus, we believe that this project contributed to better understand the participation of M2 in the pathology of atherosclerosis
309

The impact of clinical pharmacy services on the low-density lipoprotein goal attainment with lipid lowering therapies.

January 2008 (has links)
Chung, Jennifer Siu Toye. / "June 2008." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 145-157). / Abstracts in English and Chinese, some text in appendix also in Chinese. / Abstract of Thesis in English --- p.i / Abstract of Thesis in Chinese --- p.iii / Acknowledgments --- p.v / List of Tables --- p.xi / List of Figures --- p.xiii / List of Abbreviations --- p.xiv / List of Publications and Presentations related to Thesis --- p.xvi / Contributions related to Thesis --- p.xvii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction of the Thesis --- p.1 / Chapter 1.2 --- Review on Coronary Heart Disease --- p.3 / Chapter 1.2.1 --- Definition of Coronary Heart Disease --- p.3 / Chapter 1.2.2 --- Risk factors for the development of Coronary Heart Disease --- p.3 / Chapter 1.2.3 --- Worldwide Figures for Coronary Heart Disease --- p.9 / Chapter 1.2.4 --- Coronary Heart Disease in Asia Pacific --- p.10 / Chapter 1.2.5 --- Coronary Heart Disease in Hong Kong --- p.11 / Chapter 1.3 --- Dyslipidaemia --- p.14 / Chapter 1.3.1 --- Lipid Transport and Lipoprotein Metabolism --- p.14 / Chapter 1.3.2 --- Definition and Classification of Dyslipidaemia --- p.16 / Chapter 1.3.3 --- Coronary Heart Disease and Dyslipidaemia --- p.17 / Chapter 1.3.4 --- Lifestyle Modifications for the Management of Dyslipidaemia --- p.19 / Chapter 1.3.4.1 --- Dietary Measures --- p.20 / Chapter 1.3.4.2 --- Cigarette Smoking --- p.23 / Chapter 1.3.4.3 --- Physical Activity --- p.24 / Chapter 1.3.4.4 --- Weight Control --- p.25 / Chapter 1.3.5 --- Lipid-lowering Drug Therapy for Dyslipidaemia --- p.29 / Chapter 1.3.5.1 --- Statins --- p.31 / Chapter 1.3.5.2 --- Bile Acid Sequestrants --- p.35 / Chapter 1.3.5.3 --- Fibrates --- p.36 / Chapter 1.3.5.4 --- Ezetimibe --- p.37 / Chapter 1.3.5.5 --- Nicotinic Acid Group --- p.38 / Chapter 1.4 --- International Guidelines for Dyslipidaemic Management --- p.39 / Chapter 1.4.1 --- National Service Framework for Coronary Heart Disease (UK) --- p.39 / Chapter 1.4.1.1 --- National Service Framework Lipid-lowering Goals --- p.40 / Chapter 1.4.1.2 --- The Joint British Societies' Guidelines --- p.41 / Chapter 1.4.1.3 --- Achievement of the NSF Lipid Profile Targets --- p.42 / Chapter 1.4.2 --- National Cholesterol Education Program (United States) --- p.43 / Chapter 1.4.2.1 --- The Third Report of the National Cholesterol Education Program --- p.43 / Chapter 1.4.2.2 --- Review of Clinical Trials --- p.43 / Chapter 1.4.2.3 --- Low-Density Lipoprotein Cholesterol Goal Targets --- p.46 / Chapter 1.4.2.4 --- Compliance with the NCEP ATP III Guidelines --- p.48 / Chapter 1.4.3 --- Dyslipidaemic Guidelines for Study --- p.51 / Chapter 1.5 --- Clinical Pharmacy Services --- p.52 / Chapter 1.5.1 --- The Healthcare System in Hong Kong --- p.52 / Chapter 1.5.2 --- Clinical Pharmacy Services in Hong Kong --- p.54 / Chapter 1.5.3 --- Examples of successful Clinical Pharmacy Services --- p.55 / Chapter 1.5.3.1 --- Hypertension Clinic --- p.55 / Chapter 1.5.3.2 --- Diabetes Mellitus Clinic --- p.56 / Chapter 1.5.3.3 --- Smoking Cessation Clinic --- p.57 / Chapter 1.5.3.4 --- Anticoagulation Clinic --- p.57 / Chapter 1.5.3.5 --- Haematology-oncology Clinic --- p.57 / Chapter 1.5.4 --- Pharmacist-managed Lipid Clinics --- p.58 / Chapter 1.6 --- Objective & General Aims of the Study --- p.60 / Chapter 1.6.1 --- Objectives --- p.60 / Chapter 1.6.2 --- Study Hypothesis --- p.60 / Chapter 1.6.3 --- General Aims of the Study --- p.60 / Chapter Chapter 2 --- Methodology of Study --- p.62 / Chapter 2.1 --- Background Setting --- p.62 / Chapter 2.2 --- Subject Selection and Recruitment --- p.62 / Chapter 2.3 --- Intervention and Control Groups --- p.63 / Chapter 2.4 --- Validation of Survey --- p.67 / Chapter 2.5 --- Data Collection --- p.67 / Chapter 2.6 --- Outcome Measures --- p.68 / Chapter 2.6.1 --- Lipid value changes --- p.68 / Chapter 2.6.2 --- Compliance rate with medications --- p.68 / Chapter 2.6.3 --- Patient satisfaction survey assessment --- p.69 / Chapter 2.6.4 --- Time spent and Cost of clinical pharmacist --- p.69 / Chapter 2.7 --- Statistical Analysis --- p.70 / Chapter 2.7.1 --- Sample Size Calculation --- p.70 / Chapter 2.7.2 --- Methods of Statistical Analysis --- p.71 / Chapter Chapter 3 --- Results of Study --- p.72 / Chapter 3.1 --- Recruitment Details --- p.72 / Chapter 3.2 --- Demographic Characteristics of Patients --- p.73 / Chapter 3.3 --- Drug Therapy of Patients during Study Period --- p.75 / Chapter 3.4 --- LDL-C Lowering Potency of Statin Doses Prescribed --- p.80 / Chapter 3.5 --- Coronary Heart Disease Risk Category of Patients --- p.84 / Chapter 3.6 --- Lipid Profile Changes --- p.85 / Chapter 3.7 --- NCEP ATP III LDL-C Goal Attainment --- p.87 / Chapter 3.8 --- Relationship between Patient Characteristics and LDL-C Goal Attainment --- p.91 / Chapter 3.9 --- Compliance with Medications --- p.94 / Chapter 3.10 --- Pharmacist Intervention --- p.98 / Chapter 3.10.1 --- Range of Pharmacist Intervention --- p.98 / Chapter 3.10.2 --- Time spent by Pharmacist --- p.100 / Chapter 3.10.2.1 --- Time spent on Documentation --- p.100 / Chapter 3.10.2.2 --- Time spent on Direct Communication with Patients --- p.101 / Chapter 3.10.3 --- Cost of Clinical Pharmacy Service at the Lipid Clinic --- p.102 / Chapter 3.10.3.1 --- Cost of Pharmacist Involvement --- p.102 / Chapter 3.10.3.2 --- Potential Healthcare Cost Saving --- p.103 / Chapter 3.11 --- Clinical Pharmacy Service Satisfaction Survey --- p.105 / Chapter 3.11.1 --- Validation of Survey --- p.105 / Chapter 3.11.2 --- Questionnaire Survey for Intervention and Control Groups --- p.107 / Chapter 3.11.3 --- Physician Questionnaire Survey on Clinical Pharmacy Service --- p.110 / Chapter Chapter 4 --- Discussion --- p.111 / Chapter 4.1 --- Clinical Outcomes of Study --- p.111 / Chapter 4.1.1 --- Changes in Lipid Parameters --- p.111 / Chapter 4.1.2 --- Reduction in CHD risk --- p.113 / Chapter 4.1.3 --- Attainment in NCEP ATP III LDL-C goals --- p.114 / Chapter 4.1.4 --- Predictors for LDL-C Goal Attainment --- p.117 / Chapter 4.2 --- Drug-related Problems --- p.119 / Chapter 4.2.1 --- Statin Dosing and LDL-C Lowering Potency --- p.119 / Chapter 4.2.2 --- Adherence to Drug Therapy --- p.121 / Chapter 4.2.3 --- Polypharmacy --- p.126 / Chapter 4.2.4 --- Adverse Drug Events and Drug Interactions --- p.129 / Chapter 4.2.5 --- Patient Busy Lifestyle --- p.131 / Chapter 4.3 --- Role of Clinical Pharmacist --- p.133 / Chapter 4.3.1 --- Role of Pharmacist --- p.133 / Chapter 4.3.2 --- Multidisciplinary Team --- p.135 / Chapter 4.3.3 --- Healthcare Cost Saving --- p.137 / Chapter 4.4 --- Limitations of Study --- p.139 / Chapter 4.5 --- Further Study --- p.142 / Chapter Chapter 5 --- Conclusion --- p.144 / Chapter 5.1 --- Conclusion of Study --- p.144 / Bibliography --- p.145 / Appendices --- p.158 / Appendix I Data collection form --- p.158 / Appendix II Information sheet on study protocol to patient --- p.160 / Appendix III Patient consent form for study --- p.164 / Appendix IV Framingham risk scoring system for male --- p.165 / Appendix V Framingham risk scoring system for female --- p.166 / Appendix VI Patient educational leaflet --- p.167 / Appendix VII Physician-pharmacist communication sheet --- p.169 / Appendix VIII Telephone checklist --- p.170 / Appendix IX Questionnaire survey provided to Intervention Group --- p.172 / Appendix X Questionnaire survey provided to Control Group --- p.174 / Appendix XI Questionnaire survey provided to Physicians --- p.176
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Role of PFOA and PFOS on Serum Apolipoprotein B, NHANES, 2005-2006

Maisonet, Mildred, Yadav, Ruby, Leinaar, Edward 01 September 2015 (has links)
Background: Exposure to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) have been associated with higher circulating concentrations of total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). ApoB is the primary apolipoprotein component of LDL-C, and acts as a ligand for LDL-C receptors in various cells throughout the body. Circulating concentrations of ApoB are considered to be a better indicator of heart disease risk than TC or LDL-C. Objectives: Explore associations of concentrations of PFOA and PFOS with serum ApoB in adults. Methods: We analyzed data from 2744, 20-80 years old participants in the 2005–2006 National Health and Nutrition Examination Survey (NHANES). Linear regression models were used to estimate adjusted predicted means of serum ApoB (in g/L) for quartiles of PFOA and PFOS (in ng/mL) to describe patterns of associations. Results: Adjusted predicted mean concentrations of serum ApoB did not appear to vary meaningfully with increasing concentrations of PFOA (Q1 1.11, Q2 1.02, Q3 1.01, Q4 1.02) or increasing concentrations of PFOS (Q1 1.06, Q2 1.05, Q3 1.07, Q4 0.99) in study participants. Conclusions: Exposure to PFOA or PFOS does not appear to alter Apo B concentrations in adults.

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