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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.
101

Efeitos da hipercolesterolemia sobre os epitélios da mucosa bucal e capacidade de cicatrização em idades precoces - crianças e jovens (estudo experimental) / Effects of children obesity on wound healing capacity and on oral epithelium

Gilberto André e Silva 29 October 2009 (has links)
A obesidade na infância e adolescência tem aumentado de forma bastante acentuada, e quando observada nos primeiros anos de vida leva um maior risco para hipercolesterolemia, hipertrigliceridemia e alterações cardiovasculares na vida adulta. Uma correlação positiva tem sido observada entre a BMI (Body Mass Index, ou índice de massa corporal) e alterações metabólicas e hematológicas, implicando em alterações na capacidade de cicatrização, na defesa imunológica e celular e no desenvolvimento de diferentes patologias. O objetivo deste estudo foi avaliar os efeitos das fases iniciais da hipercolesterolemia, ou seja, nas idades infantil e juvenil e com pequeno aumento de colesterol, sobre os tecidos bucais e a capacidade de cicatrização. A Ratos Wistar (40g de peso) foi oferecido uma ração preparada com 1% de aumento (em peso) de colesterol + 20% de gordura (óleo de soja) por um período de 2 e 6 semanas para avaliação dos tecidos bucais. Após 2 semanas do uso da ração enriquecida com colesterol foram realizadas feridas cirúrgicas no dorso dos animais para avaliação da cicatrização. Ao final dos tratamentos propostos, os animais foram sacrificados, e colhidas as peças utilizadas (sangue, pele, língua, palatos e região gengival). O sangue coletado foi centrifugado e o soro foi utilizado para avaliação das lipoproteínas - colesterol total, HDL, LDL, VLDL e triglicérides em espectrofotômetro de absorbância. As peças colhidas foram levadas para fixação e descalcificação de acordo com a necessidade, processadas para inclusão em parafina, cortadas com 6 µm de espessura, montadas em lâminas de vidro e coradas com hematoxilina e eosina. Essas peças foram utilizadas para avaliação histológica dos tecidos e do processo de cicatrização, por meio de técnicas morfométricas. Os dados colhidos foram apresentados em valores médios, e as diferenças analisadas por testes estatísticos adequados para a comparação entre as amostras. Nossos resultados mostram que a hipercolesterolemia provocou alterações em tecidos epiteliais e que esses efeitos parecem ser progressivos, ou seja, se tornam mais expressivos com o uso continuado de alimentação com índice de colesterol aumentado, e que existe um aparente atraso no processo de cicatrização nos indivíduos que utilizam dieta hipercolesterolêmica. Consideramos que essas alterações podem tornar esses indivíduos mais suscetíveis a alterações bucais e prejudicar as reações teciduais frente a injúrias, o que pode ser preocupante durante um tratamento odontológico, principalmente cirúrgico mas também em situações de reabilitação oral ou em tratamentos odontológicos de rotina. / Obesity in childhood has becoming a concern. Obesityy is associated with increased triglycerides, decreased high-density lipoprotein cholesterol levels, and increased low-density lipoprotein cholesterol and may lead to increased risk for hypercholesterolemia and cardiovascular complications in adult life. Clinical symptoms and signs of elevated cholesterol levels do not occur until adulthood, but subclinical aspects may be observed in children and adoslecentes. There are no studies on the effects of hypercholesterolemia in children, adolescents or in adults on oral tissues. We propose to study the influence of early age hypercolesterolemia in epithelial oral tissues and on wound healing. Male albino Wistar rats (40g) received enriched cholesterol diet (1%) for 2 and six weeks for epithelial evaluation. After 2 weeks, one control group (receiving standard pellet diet) and treated (hypercholesterolemic diet) received surgical wounds at the dorsum. Animals were sacrifed 1, 3 and 7 days after surgery. At the end of both periods (2 and 6 weeks) animals were sacrificed for epithelial evaluation. At the sacrifice time, serum were collected for evaluation of triglycerides, total cholesterol, HDL, LDL and VLDL. Were collected skin, tongue, palate and gingival tissues. Skin samples were also used for evaluation of the wound healing. All the observation were made at light microscopy. Data were statistically analysed by Mann Whitney U test for comparison between two samples. P[U] ≤0.05 were considered statistically significant. The enriched cholesterol diet significantly increased the total cholesterol, triglycerides, LDL and VLDL plasma content, and the study provide support for the hypothesis that hypercholesterolemia may be associated with deficiencies in the wound healing process. An important clinical implication of this study is the identification of alterations epithelium on oral tissues and in early phases of wound healing associated with subclinical but important alterations in cholesterol levels.
102

Efeitos do treinamento físico sobre a remoção plasmática de nanopartículas lipídicas que se ligam a receptores de LDL e sobre a oxidação da lipoproteína, em indivíduos hipercolesterolêmicos / Effects of exercise training on plasma removal of lipidic nanoparticle which binds to LDL receptors and on lipoprotein oxidation, in hypercholesterolemic individuals

Ficker, Elisabeth Salvatori 30 July 2007 (has links)
A hipercolesterolemia é o maior fator de risco para doença arterial coronária e é responsável por um número significante de doenças e mortes. Há evidências que o exercício físico diminui o risco cardiovascular exercendo efeitos benéficos sobre os fatores de risco, incluindo o metabolismo lipídico. Mudanças que ocorrem no metabolismo da LDL podem não ser detectadas através das dosagens rotineiras de lípides plasmáticos. Portanto, avaliamos os efeitos do exercício físico no metabolismo de uma nanoemulsão lipídica artificial com comportamento metabólico semelhante ao da LDL. Foram avaliados 12 indivíduos hipercolesterolêmicos sedentários (H) e 12 indivíduos normolipidêmicos sedentários (N) que foram submetidos a treinamento durante 4 meses. Nos grupos controle, foram estudados 8 indivíduos hipercolesterolêmicos sedentários controle (HC) e 8 indivíduos normolipidêmicos sedentários controle (NC) que não realizaram exercício físico. A emulsão marcada com éster de colesterol -14C (EC-14C) foi injetada endovenosamente. Amostras de sangue foram coletadas em tempos prédeterminados (5 min, 1, 2, 4, 6, 8, 24 horas) após a injeção, para determinação da radioatividade, das curvas de decaimento plasmático e cálculo da taxa fracional de remoção (TFR) dos lípides marcados, por análise compartimental. As avaliações foram feitas antes e após o protocolo de treinamento físico e nos grupos controle foram realizadas 2 avaliações, sendo a segunda 4 meses após a primeira. No grupo H, as concentrações plasmáticas de colesterol total e LDL-c diminuíram (5%, p= 0,0334 e 14%, p= 0,0058), respectivamente, enquanto que, HDL-c, TFR-EC-14C e lag time aumentaram (13%, p= 0,0142; 36%, p= 0,0187; 37%, p= 0,0039), respectivamente após o treinamento físico. No grupo N, a concentração plasmática da HDL foi maior (15%, p= 0,0243), após o treinamento. Nos grupos HC e NC os parâmetros avaliados foram semelhantes. Portanto, o exercício físico acelera a remoção plasmática da LDL em indivíduos hipercolesterolêmicos, indicado pela maior TFR-EC-14C. Este efeito pode ser um dos mecanismos pelos quais o exercício previne a doença arterial coronária. / Hypercholesterolemia has become one of the major risk factors for arterial coronary disease. As such, it is also responsible for a significant number of diseases and deaths. Evidence suggests that physical exercise can, in fact, decrease the risk of cardiovascular diseases by exerting beneficial effects upon the risk factors, including lipid metabolism. The changes that do occur in LDL metabolism are generally not detected by routine clinical laboratory plasma lipid exams. In the present study, the effects of physical exercise on the metabolism of an artificial lipidic nanoemoulsion with similar LDL metabolic behavior were analyzed. 12 hypercholesterolemic sedentary individuals (H) and 12 normolipidemic sedentary individuals (N) were studied. These 24 participants were submitted to a routine training program during a 4-month period. The control group was divided into two groups: one of 8 hypercholesterolemic sedentary individuals (CH) and the other with 8 normolipidemic sedentary individuals (CN) which did not partake in any exercise program. An emulsion labeled with 14Ccholesteryl ester (14C-CE) was endovenously injected into all 4 groups. Blood samples were collected at pre-determined periods (5 min, 1, 2, 4, 6, 8 and 24 hours) after the injection of the emulsion, in order to determine the radioactivity of the plasma decay curves and calculate the fractional clearance rate (FCR) of the labeled lipids for compartimental analysis. Evaluations were made before and after the exercise training protocol. The control groups under went 2 evaluations, the second one 4 months after the first evaluation. In the H group, total cholesterol and LDL-c plasma concentrations decreased (5%, p=0.0334 and 14%, p=0.0058), respectively. HDL-c, 14C-CE-FCR and lag time, on the other hand, increased (13%, p=0.0142; 36%, p=0.0187; 37%, p=0.0039) after exercise training. HDL plasma concentration for the N group was higher (15%, p=0.0243), after exercise training. In groups CH and CN the parameters evaluated were similar. Therefore, exercise accelerates the removal of LDL plasma in hypercholesterolemic individuals as indicated by a higher 14C-CE-FCR. This effect can thus be one of the mechanisms by which exercise can prevent arterial coronary disease.
103

Obesidade, desregula??o insul?nica e lipidemia mista em equinos da ra?a mangalarga marchador / Obesity, insulin deregulation and mixed lipidemia in horses of the mangalarga walker breed

Mello, Erica Bertha Fuhrich Raupp Bezerra de Mello 25 October 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-08-22T12:11:35Z No. of bitstreams: 1 2016 - Erica Bertha Fuhrich Raupp Bezerra de Mello.pdf: 1405623 bytes, checksum: 5fa531efb35b7236db276d4de4b56a2e (MD5) / Made available in DSpace on 2017-08-22T12:11:35Z (GMT). No. of bitstreams: 1 2016 - Erica Bertha Fuhrich Raupp Bezerra de Mello.pdf: 1405623 bytes, checksum: 5fa531efb35b7236db276d4de4b56a2e (MD5) Previous issue date: 2016-10-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Increased indicators of fat metabolism are found in Equine Metabolic Syndrome (EMS) subjects although these symptons are not included in the EMS definition described in the literature and in its diagnosis. 18 mares were allocated in three groups according to body condition status. In Group Ideal there were animals in fit condition (n=6), in Group Overweight, considered in overweight (n=6) and in Group Obese (n=6), animals considered obese. Fasting blood samples were taken to determine triglycerides, total cholesterol, glucose, and insulin concentrations in plasma. Insulin sensitivity proxy (RISQI) and ?-pancreatic secretion proxy (MIRG) were calculated from glucose and insulin data. There was a difference between groups in triglycerides levels (p<0.01), where Group Obese had significantly higher concentrations than other groups. Total cholesterol was higher in Group Obese compared to Group Ideal (p=0.01). No differences in plasma glucose (p=0.53) nor insulin (p = 0.10) concentrations and insulin sensitivity (RISQI: p=0.46) were seen among groups. Group Obese had a higher ?-pancreatic secretion (MIRG: p=0.05) compared to Group Ideal. The increased body condition score influenced the results of fat metabolites and ?-pancreatic secretion / O aumento das concentra??es de indicadores do metabolismo de gorduras ? bastante comum em casos diagnosticados de S?ndrome Metab?lica Equina (SME), mas apesar disto n?o entra no hall de fatores determinantes para diagn?stico da SME. Para avaliar a influ?ncia do escore corporal (EC) nas altera??es secund?rias associadas ? SME, foram avaliados lipidograma, glicemia, concentra??o de insulina, sensibilidade ? insulina (RISQI) e secre??o ?-pancre?tica de tr?s grupos de de ?guas Mangalarga Marchador n?o-getsantes/n?o-lactantes em tr?s diferentes categorias de EC (Ideal, Sobrepeso e Obeso). Cada grupo contou com 6 animais. Foram coletadas amostras de sangue em jejum de concentrado para a determina??o de concentra??o plasm?tica de triglicer?deos, colesterol total, glicose e insulina e a partir dos valores de glicemia e insulinemia foram calculados valores preditivos de sensibilidade ? insulina (RISQI) e secre??o ?-pancre?tica (MIRG). Houve diferen?a estat?stica entre os grupos quando avaliado os n?veis de triglicer?deos (p<0,01), sendo que o Grupo Obeso apesentou resultados significativamente superiores aos demais grupos. Foi observada diferen?a estat?stica entre os grupos quando avaliado as concentra??es de colesterol total (p=0,01), sendo que o Grupo Obeso apresentou resultados significativamente superiores ao Grupo Ideal. N?o foi observada diferen?a estat?stica entre os grupos nas concentra??es plasm?ticas de glicose (p=0,53) e insulina (p=0,10). N?o foi observada diferen?a estat?stica nos valores obtidos de RISQI (p=0,46), mas houve diferen?a estat?stica entre os grupos nos valores obtidos de MIRG (p=0,05), sendo que o Grupo Obeso obteve resultados significativamente superiores quando comparado com o Grupo Ideal. O escore corporal influenciou de forma positiva nos resultados do lipidograma e valor preditivo de secre??o ?-pancre?tica, sendo encontrados maiores n?veis em animais obesos.
104

A new strategy to determine whose cholesterol to measure for primary prevention of cardiovascular disease: a modelling study using UK and Chinese data. / 設計並評估一個新的心血管初級預防中使用的膽固醇篩查模型: 中英代表性人群模型研究 / She ji bing ping gu yi ge xin de xin xue guan chu ji yu fang zhong shi yong de dan gu chun shai cha mo xing: Zhong Ying dai biao xing ren qun mo xing yan jiu

January 2012 (has links)
目的:針對心血管初級預防,世界各國均推薦某一年齡段人群全部測量膽固醇以估算心血管病發病風險。此舉耗費高且非必須,本研究旨在建立並驗證一個新型的选择性膽固醇篩查模型,用以篩查需藥物治療之高危人群,并在成本效益方面與其它篩查模型相比較。 / 方法:本模型具體采用兩步法:首先利用一個足夠高的假設膽固醇值代入心血管病風險預測方程,用以系統性的高估絶大多數人的心血管病風險;其次只有假設心血管病風險高於推薦治療閾值時,該個體才需要測量膽固醇,並進行實際心血管病風險分析。 / 英国健康调查和中国营养与健康调查是本次研究的合适数据。我們首先探索最優的假設膽固醇值,尋找到最後膽固醇值之後,我們將繼續測試我們的新型膽固醇篩查模型,在不同的治療閾值下,表現是否穩定。我們以靈敏度,特異度和徐篩查人群為指標,比較我們模型與全民篩查模型和英國NICE 選擇篩查模型相比較。之後我們估算在中英人群中應用該篩查模型,所需耗費的成本和可預防心血管事件數。 / 结果:與全名篩查模型相比,我們的模型靈敏度相若但可以節省80%左右的篩查費用。模型的靈敏度主要取決於所採用的假設膽固醇值,與所用風險預測方程,治療閾值和人群心血管風險分佈無關。當以均數加2 倍標準差作為假設膽固醇值時,靈敏度可達到97.5%左右,特異度可以達到90%左右,符合預期。模型應用於中國人群得到的結果類似。值得註意的是,在中國人群中,即使不測量膽固醇,模型靈敏度亦接近95%。此外,將膽固醇篩查項目限制于男性50-84歲,女性60-84 歲年齡段可以進一步減少篩檢費用。在人群影響方面,我們模型可預防心血管事件數比全名篩查模型略少,但成本大大降低。英國NICE 模型適用於某些特定情況,但並非全部。 / 結論:我們的新型篩查模型靈敏度與全民篩查模型相若,但可以節省大量篩查費用。在资源匮乏地区,可考虑在某一特定年龄段运用我们的模型已达到进一步减少费用的效果。如果本研究结果得到进一步数据证实,對於中國人群而言,膽固醇測量可能並非心血管風險評估所必須。 / Objectives / Since the mid 1990s, most guidelines on primary prevention of cardiovascular disease (CVD) have recommended regular cholesterol measurement for all adults or those above a certain age (which is known as mass screening). Cholesterol measurement comprises a large cost of CVD prevention and is not necessarily required in those who do not need drug intervention. In order to reduce this cost, we have developed a new selective cholesterol screening model in order to determine whose cholesterol should be measured for drug prevention. The model was evaluated and compared with other widely adopted models in basic model performance as well as cost effectiveness. / Methods / The new model has two steps. In the first step, we purposely over-estimated the majority of respondents’ CVD risk by substituting a sufficiently high hypothetical cholesterol value in the risk estimation. We then recommend cholesterol measurement only to those with the estimated CVD risk above a predetermined risk threshold for drug treatment. In the second step, the CVD risk is re-estimated based on the individual’s real cholesterol consentration. Those with a risk above the treatment threshold are recommended for drug treatment. / We evaluated the performance of our two-step model with data from the Health Survey for England and re-evaluated it with data from the China Nutrition and Health Survey 2002. By varying the hypothetical cholesterol values and treatment thresholds in CVD risk, we assessed the sensitivity, specificity and proportion of the population who need to measure cholesterol and compared it with the US mass screening model and the UK NICE selective screening model. We further compared the costs and CVD events avoided in the compared screening programmes. We also examined how the age restriction should be set in cholesterol screening programmes. / Results / As compared to mass screening, our new model can achieve a high sensitivity and save some 80% the cost of cholesterol measurements. The sensitivity depends mainly on the hypothetical cholesterol level used and seems independent of population’s CVD risk, treatment cut-off values and risk prediction model. The model performed well in almost all the conditions tested. When the hypothetical cholesterol was set at MEAN+2SD, the resulting sensitivity of our selective screening model was almost always above 95% and close to the expected 97.5%. The sensitivity was only compromised slightly if cholesterol is not measured at all for the Chinese population. Furthermore, in order to save more costs, cholesterol measurement could be better restricted to men aged 50-84 and women 60-84 years regardless of the screening model used. In CVD events prevented, mass screening is always the best but our model can prevent almost as many. In costs, mass screening is always the most expensive but our model can save all or most of the cost. The NICE selective model can perform as well as our model only when it is used in an appropriate manner and in certain circumstances. / Conclusion / Our new cholesterol screening model has a high sensitivity which is comparable to that of universal screening programs but can save most of the cost on cholesterol measurements. In where resources are particular sparse, our model can also perform well by applying it only to certain age groups, which will further save cholesterol measurement costs. Cholesterol measurement could even be completely avoided for the Chinese population if our findings can be re-confirmed correct with more updated data. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Hu, Xuefeng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 114-121). / Abstract also in Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iv / Acknowledgements --- p.vi / Abbreviations used in the thesis --- p.viii / List of Tables --- p.xvi / List of Figures --- p.xviii / List of Boxes --- p.xix / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- The burden of cardiovascular disease --- p.1 / Chapter 1.2 --- Primary prevention of CVD --- p.2 / Chapter 1.3 --- The high-risk individual strategy for CVD primary prevention --- p.3 / Chapter 1.3.1 --- The high risk individual strategy is effective --- p.4 / Chapter 1.3.2 --- The high risk individual strategy is cost-effective --- p.4 / Chapter 1.4 --- Who should be treated with drugs? --- p.5 / Chapter 1.4.1 --- The single risk factor strategy --- p.5 / Chapter 1.4.2 --- The overall CVD risk strategy --- p.7 / Chapter 1.4.3 --- Scope of CVD primary prevention --- p.8 / Chapter 1.5 --- Methods for assessing the CVD risk --- p.9 / Chapter 1.6 --- Current strategies for cholesterol measurements --- p.10 / Chapter 1.6.1 --- United States National Cholesterol Education Program --- p.13 / Chapter 1.6.2 --- American Heart Association CVD and Stroke prevention guideline --- p.14 / Chapter 1.6.3 --- The U.S. Preventive Services Task Force guideline --- p.15 / Chapter 1.6.4 --- New Zealand guideline 2003 --- p.16 / Chapter 1.6.5 --- Australian guideline 2009 --- p.17 / Chapter 1.6.6 --- The Joint British Society guideline-2 --- p.17 / Chapter 1.6.7 --- UK Department of Health guideline on vascular check --- p.18 / Chapter 1.6.8 --- China Blood Lipid Modification Guideline 2007 --- p.18 / Chapter 1.6.9 --- Summary of the reviewed guidelines --- p.19 / Chapter 1.7 --- Rationale for a selective screening model --- p.20 / Chapter 1.8 --- The UK NICE model --- p.22 / Chapter 1.9 --- Objectives of this study --- p.24 / Chapter 2 --- Methods --- p.25 / Chapter 2.1 --- The new cholesterol screening model --- p.25 / Chapter 2.2 --- Framework for evaluating the new screening model --- p.27 / Chapter 2.3 --- Indexes for evaluating the basic performance of screening models --- p.28 / Chapter 2.3.1 --- Sensitivity, specificity and % need cholesterol measurement --- p.28 / Chapter 2.3.2 --- Sensitivity analysis for model performance --- p.29 / Chapter 2.3.2.1 --- Using different hypothetical cholesterol values --- p.29 / Chapter 2.3.2.2 --- Using different treatment cut-off thresholds --- p.30 / Chapter 2.3.2.3 --- Using different populations --- p.30 / Chapter 2.3.2.4 --- Using different risk equations --- p.31 / Chapter 2.4 --- Data --- p.31 / Chapter 2.4.1 --- The Health Survey for England --- p.31 / Chapter 2.4.1.1 --- Background and aim of the survey --- p.31 / Chapter 2.4.1.2 --- Survey design --- p.32 / Chapter 2.4.1.2.1 --- Sampling Frame --- p.32 / Chapter 2.4.1.2.2 --- Weighting variables --- p.33 / Chapter 2.4.1.3 --- Data collection --- p.33 / Chapter 2.4.1.3.1 --- Blood cholesterol --- p.34 / Chapter 2.4.1.3.2 --- Blood pressure --- p.34 / Chapter 2.4.1.3.3 --- Smoking --- p.34 / Chapter 2.4.1.3.4 --- History of CVD and diabetes --- p.34 / Chapter 2.4.1.3.5 --- Treatment history --- p.35 / Chapter 2.4.2 --- The 2002 China National Nutrition and Health Survey --- p.35 / Chapter 2.4.2.1 --- Survey design --- p.36 / Chapter 2.4.2.2 --- Data collection --- p.36 / Chapter 2.4.2.2.1 --- Blood pressure --- p.36 / Chapter 2.4.2.2.2 --- Blood cholesterol --- p.38 / Chapter 2.4.2.2.3 --- Smoking --- p.38 / Chapter 2.4.2.2.4 --- History of CVD, diabetes and drug treatment --- p.38 / Chapter 2.4.3 --- Subjects eligible for analysis in this study --- p.38 / Chapter 2.5 --- CVD risk prediction --- p.43 / Chapter 2.5.1 --- The Framingham risk equation for the UK population --- p.43 / Chapter 2.5.2 --- The Asian equation for the Chinese population --- p.44 / Chapter 2.5.3 --- Adjusting for cholesterol and blood pressure --- p.45 / Chapter 2.5.4 --- Deriving the hypothetical cholesterol --- p.46 / Chapter 2.6 --- Identifying the appropriate age ranges for cholesterol measurement --- p.47 / Chapter 2.7 --- Comparing various screening models and options --- p.47 / Chapter 2.7.1 --- Compared screening models and options --- p.47 / Chapter 2.7.1 --- Indices for the performance of the screening options --- p.49 / Chapter 2.7.2 --- Costs of different screening options --- p.50 / Chapter 2.7.2.1 --- Components of screening cost from societal perspective --- p.50 / Chapter 2.7.2.1.1 --- Cost for inviting people for data collection --- p.50 / Chapter 2.7.2.1.2 --- Cost for the full risk assessment --- p.51 / Chapter 2.7.2.1.3 --- Treatment cost --- p.51 / Chapter 2.7.2.1.4 --- Cost saved for avoided CVD events --- p.52 / Chapter 2.7.2.2 --- Components of screening cost from health system’s perspective --- p.52 / Chapter 2.7.3 --- Number of CVD events avoidable --- p.53 / Chapter 2.8 --- Statistical analysis --- p.54 / Chapter 2.8.1 --- Descriptive analysis --- p.54 / Chapter 2.8.2 --- Cross-tabulation analysis --- p.54 / Chapter 2.8.3 --- Survey data analysis --- p.54 / Chapter 3 --- Results --- p.57 / Chapter 3.1 --- Description of data --- p.57 / Chapter 3.1.1 --- The UK population --- p.57 / Chapter 3.1.1.1 --- Sumamry of CVD risk and risk factors --- p.57 / Chapter 3.1.1.2 --- Distribution of age --- p.57 / Chapter 3.1.1.3 --- Distribution of blood pressure and blood cholesterol --- p.58 / Chapter 3.1.1.4 --- Distribution of the predicted 10-year CVD risk --- p.62 / Chapter 3.1.1.5 --- Relation between the risk threshold and age --- p.63 / Chapter 3.1.2 --- The Chinese population --- p.65 / Chapter 3.1.2.1 --- Summary of CVD risk and risk factors --- p.65 / Chapter 3.1.2.2 --- Distribution of age --- p.65 / Chapter 3.1.2.3 --- Distribution of blood pressure and blood cholesterol --- p.66 / Chapter 3.1.2.4 --- Distribution of the predicted 10-year CVD risk --- p.69 / Chapter 3.1.2.5 --- Relation between the risk threshold and age --- p.70 / Chapter 3.2 --- Performance of our new screening model --- p.72 / Chapter 3.2.1 --- Performance according to cholesterol values in the UK population --- p.72 / Chapter 3.2.2 --- Performance according to treatment cut-offs in the UK population --- p.73 / Chapter 3.2.3 --- Performance according to cholesterol values in the Chinese population --- p.73 / Chapter 3.2.4 --- Performance according to the risk cut-offs in the Chinese population --- p.74 / Chapter 3.2.4 --- Performance using different risk equations --- p.76 / Chapter 3.3 --- Comparison with other existing screening models --- p.77 / Chapter 3.3.1 --- Performance of the 3 models within an age-restricted UK population --- p.79 / Chapter 3.3.2 --- Performance of the 3 models within an age-restricted Chinese population --- p.81 / Chapter 3.3.3 --- Performance of the 3 models in the entire UK population --- p.83 / Chapter 3.3.4 --- Performance of the 3 models in the entire Chinese population --- p.84 / Chapter 3.3.5 --- Costs of various screening options --- p.87 / Chapter 3.3.6 --- Number of CVD events avoidable of the screening programmes --- p.92 / Chapter 4 --- Discussion --- p.96 / Chapter 4.1.1 --- Performance at different hypothetical cholesterol values --- p.96 / Chapter 4.1.2 --- Performance at various treatment cut-off thresholds --- p.97 / Chapter 4.1.3 --- Performance with different risk equations --- p.98 / Chapter 4.1.4 --- Performance in different populations --- p.99 / Chapter 4.1.5 --- Performance with different survival functions --- p.99 / Chapter 4.2 --- Further modifications of the model --- p.100 / Chapter 4.2.1 --- A model without any cholesterol measurement --- p.100 / Chapter 4.2.2 --- Age restriction for selective models --- p.102 / Chapter 4.2.3 --- Our model with potential personalized treatment cut-off --- p.103 / Chapter 4.2.4 --- Three key things to ensure model performance in other population --- p.104 / Chapter 4.3 --- CVD events preventable --- p.105 / Chapter 4.3.1 --- Importance of age restriction --- p.105 / Chapter 4.3.2 --- Limitations of the NICE model --- p.106 / Chapter 4.4 --- Costs of different screening models --- p.107 / Chapter 4.4.1 --- Cost from different perspectives --- p.107 / Chapter 4.4.2 --- Cholesterol measurement cost and routine data collection --- p.108 / Chapter 4.4.3 --- Cost components --- p.109 / Chapter 4.4.4 --- Ways to reduce cholesterol measurement costs --- p.109 / Chapter 4.4.5 --- Costs and gain of the missing 2.5% high risk individuals --- p.109 / Chapter 4.5 --- Strengths and limitations of this study --- p.110 / Chapter 4.6 --- Recommendations --- p.113 / References --- p.114
105

Estudo da reserva de perfusão miocárdica pelo ecocardiograma com contraste em tempo real, em indivíduos com hipercolesterolemia grave, antes e após tratamento com inibidores da HMG-CoA redutase / Evaluation of myocardial perfusion reserve in severe hypercholesterolemic patients with real time contrast echocardiography, before and after treatment with HMG-CoA reductase inhibitors

Lario, Fábio de Cerqueira 02 June 2009 (has links)
INTRODUÇÃO: A hipercolesterolemia provoca alterações inflamatórias no sistema cardiovascular, induzindo disfunção endotelial e mudanças estruturais na microcirculação, com alterações significativas da homeostase vascular, processo este reversível com o tratamento hipolipemiante. Clinicamente, tais fenômenos podem ser demonstrados pela avaliação da reserva de fluxo coronário e da reatividade vascular periférica. A ecocardiografia de perfusão miocárdica em tempo real (EPMTR) possui características que a tornam ideal para a avaliação da microcirculação coronária, como a utilização de contrastes intravasculares, além de ótimas resoluções temporal e espacial. MÉTODOS: 16 pacientes com hipercolesterolemia e sem lesões coronárias obstrutivas (grupo HF) e 10 indivíduos saudáveis, sem doença arterial coronária obstrutiva estabelecida (grupo controle) foram avaliados por EPMTR e por ultrassonografia da artéria braquial em dois momentos: pré-tratamento com atorvastatina no grupo HF (período livre de medicação >6 semanas) e 12 semanas após o primeiro exame. A análise do fluxo miocárdico foi realizada nos 17 segmentos do ventrículo esquerdo obtendo-se índices de volume de sangue relativo no miocárdio (AN), da velocidade do fluxo () e do fluxo miocárdico absoluto (ANx) na condição de repouso e durante a vasodilatação com adenosina. A reserva de fluxo foi definida como a razão entre o fluxo durante vasodilatação e o fluxo do repouso. Para estudo da reatividade vascular periférica, todos os indivíduos foram submetidos à ultrassonografia da artéria braquial, com avaliação dos diâmetros da artéria braquial antes e depois de um período de isquemia de 5 minutos. RESULTADOS: Os dois grupos foram comparáveis quanto à idade, sexo, peso, superfície corpórea, índice de massa corpórea, índice de massa do VE, frequência cardíaca e pressões arteriais sistólica e diastólica, tanto no repouso quanto durante a infusão de adenosina. Os valores evolutivos de LDL-C (mg.dL-1) nos dois momentos foram 106±36 e 107±35; p=NS para o grupo controle vs 278±48 e 172±71; p<0,001 para o grupo HF. Na avaliação inicial, a dilatação braquial estava reduzida nos pacientes do grupo HF 0,08±0,04 vs 0,15±0,02; p<0,001 relativamente ao grupo controle, com aumento do diâmetro arterial basal (mm): 3,42±0,63 vs 3,07±0,53; p<0,001. O grupo HF, quando comparado ao grupo controle na avaliação inicial, apresentava valores mais altos de AN: (dB) 0,56±0,08 vs 0,49±0,05; p=0,02, de (s-1) 0,56±0,14 vs 0,45±0,04; p=0,02 e ANx: (dB.dB-1 s-1) 0,28±0,06 vs 0,20±0,02; p<0,001, maiores valores de AN: durante infusão de adenosina 0,64±0,08 vs 0,57±0,06; p=0,001 e menores reservas de : 2,59±0,61 vs 3,25±0,45; p=0,001 e de ANx: 2,78±0,71 vs 3,43±0,66; p=0,03. Após o uso de atorvastatina, as alterações foram revertidas, tanto na circulação periférica quanto na coronária. CONCLUSÕES: A EPMTR monstrou que em indivíduos com hipercolesterolemia e sem doença coronária obstrutiva existe aumento do fluxo microvascular em repouso e redução da reserva de fluxo miocárdico. Após o tratamento com atorvastatina houve normalização do fluxo em repouso. Adicionalmente, alterações similares ocorreram na circulação periférica dos indivíduos hipercolesterolêmicos, revertidas por utilização da atorvastatina. / BACKGROUND: Hypercholesterolemia induces inflammatory changes on the cardiovascular system, causing endothelial dysfunction and structural alterations of microcirculation, with substantial imbalance of vascular homeostasis. Reduction of blood cholesterol levels can stop these processes. These circulation alterations can be demonstrated by coronary flow reserve and peripheral vascular reactivity evaluation. Real time myocardial perfusion echocardiography (EPMTR) is an excellent method to demonstrate coronary microcirculation alterations, as ultrasound contrast agent has rheological properties close to red cells. Additionally, EPMTR has optimal spatial and temporal resolutions. METHODS: 16 patients with hypercholesterolemia (group-HF) without overt obstructive coronary disease and 10 healthy volunteers (group-C) were evaluated by EPMTR and vascular ultrasound in 2 moments: before atorvastatin treatment (group-HF, >6 weeks free of statin) and 12 weeks after beginning medication (group-HF), or 12 weeks after the first evaluation (group-C). For myocardial blood flow evaluation, the left ventricle was divided into 17 segments, and indexes of myocardial blood volume (AN), blood flow velocity (), and myocardial blood flow (ANx) were obtained for each myocardial segment at rest condition and after adenosine infusion. Myocardial flow reserve was calculated as the hyperemic to rest values of AN, e ANx. Peripheral vascular reactivity was evaluated by vascular ultrasound. Measures of braquial artery diameter were obtained before and after 5 minutes of arterial flow occlusion. RESULTS: Both groups were comparable for age, sex, body weight, body surface area, body mass index, left ventricular mass index, heart rate, and systolic and diastolic arterial blood pressure. These variables were also comparable, under basal or adenosine stress conditions. LDL-C values (mg.dL-1) in different moments (intra-group) were 106±36 and 107±35; p=NS for group-C vs 278±48 and 172±71; p<0,001 for group-HF. Group-HF as compared to group-C had higher initial resting values of AN (dB): 0,56±0,08 vs 0,49±0,05; p=0,02, (s-1): 0,56±0,14 vs 0,45±0,04; p=0,02, and ANx (dBdB-1s-1): 0,28±0,06 vs 0,20±0,02; p<0,001, and higher hyperemic value of AN 0,64±0,08 vs 0,57±0,06; p=0,04, and lesser reserves of 2,59±0,61 vs 3,25±0,45; p=0,01 and of ANx: 2,78±0,71 vs 3,43±0,66; p=0,03. After atorvastatin treatment no difference was observed at rest, hyperemic and reserve values of AN, and ANx between the groups. CONCLUSION: In patients with hypercholesterolemia and without coronary obstruction, there was augmented myocardial blood flow and reduced coronary flow reserve at rest, compared to healthy volunteers. After atorvastatin treatment at rest myocardial blood flow was normalized in those patients. Additionally, similar alterations in peripheral circulation could be demonstrated in hypercholesterolemia, and were reverted with atorvastatin.
106

Racial Disparities Study in Diabetes-Related Complication Using National Health Survey Data

Yan, Fengxia 15 December 2010 (has links)
The main aim of this study is to compare the prevalence of diabetes-related complications in white to the prevalence in other racial and ethnic groups in United States using 2009 Behavioral Risk Factor Surveillance System (BRFSS). By constructing the logistic regression model, odds ratios (OR) were calculated to compare the prevalence of diabetes complications in white and other groups. Compared to white, the prevalence of hypertension and stroke in African Americans were higher, while the prevalence of heart attack and coronary heart disease were lower. The Asian Americans or Pacific Islanders, African Americans and Hispanics were more likely to develop retinopathy compared to white. The prevalence of hypertension, hypercholesterolemia, heart attack, coronary heart disease, Stroke in Native Americans and “other” group were not significantly different from the prevalence in white. Asian or Pacific Islanders were less likely to experience stroke.
107

Mechanical and Histological Characterization of Porcine Aortic Valves under Normal and Hypercholesterolemic Conditions

Sider, Krista 12 December 2013 (has links)
Calcific aortic valve disease (CAVD) is associated with significant cardiovascular morbidity. While late-stage valve disease is well-described, there remains an unmet scientific need to elucidate early pathobiological processes. In CAVD, pathological differentiation of valvular interstitial cells (VICs) and lesion formation occur focally in the fibrosa layer. This VIC pathological differentiation has been shown to be influenced by matrix stiffness in vitro. However, little is known about the focal layer specific mechanical properties of the aortic valve in health and disease and how these changes in matrix moduli may influence VIC pathological differentiation in vivo. In this thesis, micropipette aspiration (MA) was shown to be capable of measuring the mechanical properties of a single layer in multilayered biomaterial or tissue such as the aortic valve, if the pipette inner diameter was less than the top layer thickness. With MA, the fibrosa of normal porcine aortic valves was significantly stiffer than the ventricularis; stiffer locations found only within the fibrosa were comparable to stiffnesses shown in vitro to be permissive to VIC pathological differentiation. Early CAVD was induced in a porcine model, which developed human-like early CAVD lesion onlays. Extracellular matrix remodeling occurred in the absence of lipid deposition, macrophages, osteoblasts, or myofibroblasts, but with significant proteoglycan-rich onlays and chondrogenic cell presence. These early onlays were softer than the collagen-rich normal fibrosa, and their proteoglycan content was positively correlated with Sox9 chondrogenic expression, suggesting that soft proteoglycan-rich matrix may be permissive to chondrogenic VIC differentiation. The findings from this thesis shed new light on early disease pathogenesis and improve the fundamental understanding of aortic valve mechanics in health and disease.
108

Φαρμακοκινητικός και φαρμακοδυναμικός χαρακτηρισμός μιας μεταλλαγμένης μορφής της απολιποπρωτεϊνης Ε με βελτιωμένες βιολογικές ιδιότητες / Pharmacokinetic and pharmacodynamic analysis of a recombinant apolipoprotein E variant apoE4 with improved biological properties

Λαμπροπούλου, Αγγελική 31 January 2013 (has links)
Φυσιολογικά επίπεδα της αγρίου τύπου απολιποπρωτεϊνης Ε (apoE) στο πλάσμα διαμεσολαβούν στην κάθαρση των αθηρογενετικών λιποπρωτεϊνών ενώ υψηλότερα επίπεδα από τα φυσιολογικά προκαλούν υπερτριγλυκεριδαιμία. Αυτή η ιδιότητα της αγρίου τύπου apoE μειώνει σημαντικά την θεραπευτική της αξία ως ένα πιθανό βιολογικό φάρμακο για την αντιμετώπιση της δυσλιπιδαιμίας. Πρόσφατα, έχει δημιουργηθεί και μελετηθεί μια μεταλλαγμένη μορφή της apoE, apoE4 [ L261A, W264A, F265A, L268A, V269A ] (apoE4mut1) με βελτιωμένες βιολογικές ιδιότητες. Συγκεκριμένα, αυτή η μεταλλαγμένη μορφή μπορεί να φέρει τα υψηλά επίπεδα χοληστερόλης σε φυσιολογικές τιμές χωρίς να προκαλέσει υπερτριγλυκεριδαιμία ακόμα και όταν υπερεκφράζεται. Στην παρούσα μελέτη, πραγματοποιήθηκε φαρμακοδυναμική και φαρμακοκινητική ανάλυση της apoE4mut1 σε πειραματόζωα. Με γονιδιακή μεταφορά μέσω ιού σε ποντίκια που είχαν έλλειψη στον LDL υποδοχέα (LDLr-/-) και σε ποντίκια που είχαν έλλειψη στην apoE (apoE-/-), δείχθηκε οτι η δράση της apoE4mut1 ( μείωση της χοληστερόλης ) εξαρτάται από την έκφραση ενός λειτουργικού κλασσικού LDL υποδοχέα. Εφάπαξ έγχυση της apoE4mut1 συνδεδεμένης με λιποσώματα σε apoE-/- ποντίκια που ήταν σε δίαιτα δυτικού τύπου για 6 εβδομάδες αποκάλυψε οτι η εξωγενώς συντιθέμενη apoE4mut1 διατηρεί άθικτη την ικανότητά της να κανονικοποιεί τα υψηλά επίπεδα χοληστερόλης αυτών των ποντικιών με μια μέγιστη φαρμακολογική απόκριση που παρατηρείται σε μόλις 10 ώρες μετά την έγχυση. Ενδιαφέρον παρουσίασε το γεγονός οτι τα επίπεδα χοληστερόλης του πλάσματος παρέμειναν σημαντικώς μειωμένα για τις επόμενες 24 ώρες μετά την έγχυση της apoE4mut1- λιποσώματα. Μετρήσεις συγκεντρώσεων της apoE έδειξαν οτι η apoE4mut1 στην μορφή των πρωτεολιποσωμάτων που χρησιμοποιήθηκαν σε αυτή τη μελέτη έχει χρόνο ημίσειας ζωής 15.8 h. Τα δεδομένα αυτά οδηγούν στο συμπέρασμα οτι η καθαρή apoE4mut1 μπορεί να αποτελέσει ένα νέο υποψήφιο φάρμακο για την άμεση αντιμετώπιση της υπερχοληστερολαιμίας σε άτομα που εκφράζουν έναν λειτουργικό LDL υποδοχέα. / Physiological levels of wild-type (wt) apolipoprotein E (apoE) in plasma mediate the clearance of cholesterol-rich atherogenic lipoprotein remnants while higher than normal plasma apoE concentrations fail to do so and trigger hypertriglyceridemia. This property of wt apoE reduces significantly its therapeutic value as a potential biological drug for dyslipidemia. Recently, we reported the generation of a recombinant apoE variant, apoE4 [L261A, W264A, F265A, L268A, V269A] (apoE4mut1) with improved biological functions. Specifically, this variant can normalize high plasma cholesterol levels without triggering hypertriglyceridemia, even at supraphysiological levels of expression. In the present study we performed pharmacodynamic and pharmacokinetic analysis of apoE4mut1 in experimental mice. Using adenovirus-mediated gene transfer in LDL receptor deficient (LDLr-/-) and apoE deficient (apoE-/-) mice, we show that the cholesterol lowering potential of apoE4mut1 is dependent on the expression of a functional classical LDLr. Bolus infusion of apoE4mut1-containing proteoliposomes in apoE-/- mice fed western-type diet for 6 weeks indicated that exogenously synthesized apoE4mut1 maintains intact its ability to normalize the high cholesterol levels of these mice with a maximum pharmacological effect obtained at only 10 hours post-treatment. Interestingly, plasma cholesterol levels remained significantly reduced even 24 hours following intravenous infusion of apoE4mut1 proteoliposomes. Measurements of plasma apoE levels indicated that apoE4mut1 in the form of proteoliposomes used in the study has a half-life of 15.8 h. Our data suggest that purified apoE4mut1 may be an attractive new candidate for the acute correction of hypercholesterolemia in subjects expressing functional LDL receptor.
109

Avaliação dos Produtos de Degradação em Comprimidos de Sinvastatina: Estudos de Estabilidade e Validação de Métodos / Degradation Products Assessment Simvastatin Tablets: Stability Studies and Methods Validation

Fonseca, Erika Bachini January 2012 (has links)
Made available in DSpace on 2016-07-01T11:59:27Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 2.pdf: 2625869 bytes, checksum: 8cb28dd9acaae218862e11d5bbeec859 (MD5) Previous issue date: 2012 / Made available in DSpace on 2016-07-21T14:39:31Z (GMT). No. of bitstreams: 2 2.pdf: 2625869 bytes, checksum: 8cb28dd9acaae218862e11d5bbeec859 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil. / As estatinas são substâncias que reduzem os níveis lipídicos no sangue, sendo a hipercolesterolemia o fator causal da aterosclerose, doenças coronarianas dentre outras. Devido ao alto índice do distúrbio na população brasileira, as estatinas são usadas como tratamento de primeira escolha, por serem mais seguras e eficazes. Sendo que duas estatinas (a atorvastatina e a sinvastatina) fazem parte da RENAME e sinvastatina incluída no programa Aqui tem farmácia popular . Devido à ampla utilização da sinvastatina, faz-se necessária a avaliação da qualidade dos medicamentos, sendo relevante o conhecimento de sua estabilidade química e física até o fim de seu prazo de validade. O monitoramento de produtos de degradação faz parte desta avaliação e é necessária a implementação de metodologias analíticas validadas de pesquisa destas impurezas na rotina dos estudos de estabilidade. Além disso, é essencial o desenvolvimento contínuo de formulações melhoradas para garantir a disponibilidade, eficácia e segurança do fármaco. A maioria das técnicas descritas na literatura são usadas para quantificar o teor de sinvastatina e seus metabólitos no sangue. Os compêndios oficiais disponibilizam apenas metodologia para a quantificação de produtos de degradação na matéria-prima. O objetivo deste trabalho foi avaliar a formação de produtos de degradação na formulação de comprimidos durante o prazo de validade. Para isto, foram propostas a adaptação e a validação da metodologia da Farmacopéia Americana da matéria-prima. O método proposto empregou coluna cromatográfica C18 e fase móvel constituída de de solução de ácido fosfórico e acetonitrila misturados por gradiente de eluição com tempo total de corrida de 13 minutos. O fluxo empregado foi de 3 mL/min. e detecção UV/VIS a 238 nm. A metodologia apresentou resultados satisfatórios de especificidade, linearidade, precisão, exatidão e robustez. O estudo de estabilidade foi conduzido numa condição controlada de temperatura e umidade (30ºC, 75% U.R.) ao longo do prazo de validade e demonstrou que não há formação ou aumento dos níveis dos produtos de degradação na formulação de comprimidos. / Statins are substances that reduce blood lipid levels, being hypercholesterolemia the causative factor of atherosclerosis, coronary heart disease among others. Due to the high rate of the disorder in the population, statins are used as first-line treatment because of are their safety and effectiveness. Two statins (atorvastatin and simvastatin) are part of RENAME and simvastatin is included in the program "Here's pharmacy popular".Due to the wide use of simvastatin, it is necessary to evaluate the quality of drugs being relevant knowledge of their chemical and physical stability until the end of its shelf life. The monitoring of degradation products and is part of this assessment an it is necessary to implement validated analytical methodologies in the routine of stability studies. Furthermore, it is essential to continuing development of improved formulations for the availability, effectiveness and safety of the drug.Most techniques described in literature are used to quantify the amount of simvastatin and its metabolites in blood. The official compendia only provide methodology for quantification of degradation products in raw material.The aim of this study was to evaluate the formation of degradation products in tablet formulation during the shelf life. For this, was proposed adaptation and validation of the methodology of the American Pharmacopoeia of the raw material. The proposed method employed C18 chromatographic column and a mobile phase consisting of a phosphoric acid solution and acetonitrile mixed by gradient elution with a total run time of 13 minutes. The flow was 3 ml / min. and detection UV / VIS at 238 nm. The methodology presented satisfactory specificity, linearity, precision, accuracy and robustness. The stability study was conducted in a controlled condition of temperature and humidity (30 ° C, 75% RH) during the shelf life and showed no training or increased levels of degradation products in tablet formulation.
110

Rosiglitazone pode causar lesão tubular renal em ratos normais mas não em ratos hipercolesterolêmicos / Rosiglitazone may induce renal injury in normal rats but not in hypercholesterolemic rats

Cristiano Dias 27 October 2009 (has links)
Introdução: Rosiglitazone (RGL) é um ligante dos receptores PPAR e vem sendo usada no tratamento do Diabetes Mellitus tipo 2 e nas doenças inflamatórias. Mas, RGL pode reduzir a filtração glomerular (FG), a carga excretada de sódio na urina (UVNa) e aumentar a expressão da Na+,K+- ATPase na medula renal. Então, RGL pode causar edema e insuficiência cardíaca congestiva. Entretanto, não tem sido reportado se RGL pode induzir insuficiência renal aguda (IRA). Objetivo: Verificar se a redução da FG causada pelo tratamento com RGL predispõe à IRA em ratos. Avaliar em condições basais e de vasoconstrição renal e se há diferenças entre ratos normocolesterolêmicos (NC) e hipercolesterolêmicos (HC). Métodos: A FG foi medida pelo clearance de inulina no 8º dia em ratos (~200g) NC e HC tratados ou não com RGL (48 mg/kg/dieta) na situação basal e durante a infusão endovenosa de Ang II (40 ng/kg/min). Além disso, a atividade da Na+,K+-ATPase foi avaliada em homogenato renal em outra série de animais. Resultados: Na situação basal, NC e HC apresentaram FG semelhante e o tratamento com RGL reduziu a FG apenas em NC de 0,78±0,03 para 0,50±0,05* ml/min/100g, *p<0,001. Apesar da redução da FG, a UVNa em NC+RGL não se modificou. Durante a infusão de Ang II, a FG de NC, HC e HC+RGL reduziu-se para o mesmo patamar de NC+RGL e um significante aumento da UVNa foi observada apenas em NC+RGL (NC= 3,32±0,88; NC+RGL=5,86±1,04*; HC= 2,63±0,43 e HC+RGL= 2,23±0,39 uEq/min, *p<0,01). Além disso, RGL induziu aumento na atividade da Na+,K+-ATPase em HC+RGL e não modificou em NC+RGL. Os valores expressos em M Pi/mg proteína.h-1 foram de 45±7 em NC, 43±5 em NC+RGL, 48±7 em HC e 64±4* em HC+RGL, *p<0,05. Analisando todos os resultados em conjunto, a redução da FG associada com a alta natriurese e ausência da modulação da atividade da Na+,K+-ATPase em NC+RGL sugerem lesão renal neste grupo. Conclusão: Os mecanismos de ação da RGL diferem de acordo com a condição metabólica. Então, RGL deve ser prescrita com cautela na ausência de hipercolesterolemia e requer a monitoração da função renal principalmente nas situações de vasoconstrição / Introduction: Rosiglitazone (RGL) is a ligand for PPAR used to treat type 2 Diabetes Mellitus and inflammatory diseases. However, RGL can reduce the glomerular filtration rate (GFR), urinary sodium excretion (UVNa) and increase the expression of Na+, K+-ATPase in renal medulla. Thus, RGL may induce edema and congestive heart failure. However, acute renal failure (ARF) provoked by RGL treatment has not been reported. Aim: To test whether reduced GFR by RGL may predispose to ARF at baseline and during a renal vasoconstriction state, and if the findings differ between normocholesterolemic (NC) and hypercholesterolemic (HC) rats. Methods: GFR was measured by inulin clearance on the 8th day in NC and HC rats (~200g) treated or not with RGL (48 mg/kg diet) at baseline and during intravenous infusion of Ang II (40 ng/kg/min). Furthermore, the Na+,K+- ATPase activity was determined in renal homogenates in other series of animals. Results: At baseline, NC and HC had similar GFR and the treatment with RGL reduced GFR only in NC from 0.78±0.03 to 0.50±0.05* ml/min/100g, *p<0.001. Although GFR was reduced, UVNa was unchanged in NC+RGL. During Ang II infusion, GFR was significantly reduced in NC, HC and HC+RGL and it remained at the same reduced level in NC+RGL. At this time, when GFR was reduced the same range in all groups, a significant increment in UVNa was only observed in NC+RGL (NC = 3.32±0.88; NC+RGL = 5.86±1.04*; HC = 2.63±0.43 and HC+RGL = 2.23±0.39 Eq/min, *p<0.01). Moreover, RGL induced an increase in the activity of Na+, K+-ATPase in HC+RGL, but it did not modify the activity of this enzyme in NC+RGL. The values expressed in M Pi/mg.protein.h-1 were 45±7 in NC, 43±5 in NC+RGL, 48±7 in HC and 64±4* in HC+RGL, *p<0.05. Taken together, reduction in GFR associated with high natriuresis and without changes in the Na+, K+-ATPase activity in renal medulla of NC+RGL may suggest renal injury in this group. Conclusion: RGL may act distinctly in normocholesterolemia and in hypercholesterolemia. Thus, RGL may be prescribed with caution in absence of hypercholesterolemia and requires monitoring of renal function specially if a renal vasoconstriction state is associated.

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