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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.
71

Estudo comparativo da hiperplasia miointimal pós-angioplastia na artéria ilíaca externa de coelhos, com aterosclerose induzida, tratados com Allium sativum e colostazol / Comparative study of pós-angioplastia hyperplasia miointimal in the external iliac artery of rabbits, with induced atherosclerosis, treated with Allium sativum and cilostazol

Lima, Paulo Roberto da Silva 29 May 2015 (has links)
Intimal hyperplasia is associated with graft failure and vascular sutures in the first year after surgery and in postangioplasty restenosis. Allium sativum (common garlic) lowers cholesterol and has antioxidant effects; it also has antiplatelet and antitumor properties and, therefore, has great potential to reduce or inhibit intimal hyperplasia of the arteries. Attempts have been made to inhibit intimal hyperplasia of the arteries with cilostazol and other drugs. Therefore, it is important to address the following research question: what is the difference between the mean of post-angioplasty myointimal thickening in the iliac artery of rabbits treated with A. sativum and that treated with cilostazol? Our objective is to determine the mean difference of post-angioplasty myointimal hyperplasia in the external iliac artery of rabbits with induced atherosclerosis, and compare the outcome between treatment with A. sativum and treatment with cilostazol. This is a randomized preclinical trial study conducted in experimental animals. We used female New Zealand rabbits (Oryctolagus cuniculus), submitted to an atherosclerotic diet and angioplasty of the external iliac artery. The animals were divided into the following groups (n = 10 each) according to treatment: group A, A. sativum, 800 μg⋅kg-1⋅day-1, orally; group C, cilostazol, 50 mg/day, orally; group S, 10 mL of 0.9% physiological saline solution, orally. Our primary variable is the difference of the mean myointimal hyperplasia. The secondary variable is the mean plate thickness of the arterial wall. Complementary data include frequency of limb ischemia, limb loss frequency, frequency of hematoma or bruising, frequency of infection, frequency of bleeding, frequency of animal death, and mean of lipid levels. The sample size was arbitrated in 30 rabbits. Statistical analysis was performed by using ANOVA and Tukey tests, as well as the χ2 test. We calculated the 95% confidence interval (CI) for each point estimate, and the P value was set as < 0.05. Group S had a mean hyperplasia rate of 35.74% (95% CI, 31.76–39.71%); group C, 16.21% (95% CI, 13.36–19.05%); and group A, 21.12% (95% CI, 17.26–25.01%); P < 0.0001. In conclution the Allium sativum quite as effective in inhibiting myointimal hyperplasia compared with those treated with cilostazol. / A hiperplasia intimal está relacionada à falha de enxertos e suturas vasculares no primeiro ano pós-cirurgia e nas reestenoses pós-angioplastia. O Allium sativum (alho comum) reduz o colesterol e tem efeito antioxidante, antiplaquetário e antitumoral; logo havia grande possibilidade de reduzir ou inibir a hiperplasia da íntima das artérias, a qual sua inibição vem sendo tentada com o Cilostazol e outros tratamentos. Sendo assim é relevante responder a pergunta de pesquisa: qual a diferença de média de hiperplasia miointimal pós-angioplastia na artéria ilíaca de coelhos tratados com Allium sativum comparada aos tratados com Cilostazol? O objetivo é determinar a diferença de média de hiperplasia miointimal pós-angioplastia na artéria ilíaca externa de coelhos com aterosclerose induzida e tratados com Allium sativum comparada aos tratados com Cilostazol. O estudo foi um ensaio pré-clínico aleatório em animais de experimentação por 35 dias. Os animais foram coelhos fêmeas (Oryctolagus cuniculus), da linhagem Nova Zelandia, submetidos à dieta ateroslcerótica e à angioplastia da artéria ilíaca externa direita. Os animais foram divididos em: Grupo A (n=10) coelhos tratados com a Allium sativum (800 μg/kg/dia), em doses diárias, por via oral. Grupo C (n=10): coelhos tratados com Cilostazol em doses diárias de 50 mg/dia, por via oral. Grupo S (n= 10) coelhos tratados com 10 mL de soro fisiológico 0,9%, por via oral, que foi nosso controle negativo. A variável primária foi a diferença de frequência da média de hiperplasia miointimal. Variáveis secundárias: a média de espessura da placa na parede arterial. Dados complementares: a frequência isquemia do membro, a frequência de perda do membro, a frequência de hematoma ou equimose, a frequência de infecção, a frequência de sangramento, a frequência de morte do animal e a média dos níveis lipídicos. O tamanho da amostra foi arbitrado em 30 coelhos. A análise estatística foi realizada com o teste ANOVA, Qui-quadrado e Tukey. Foi calculado o intervalo de confiança de 95% para cada ponto estimado. Os resultados foram: grupo S teve um índice médio de hiperplasia de 35,74% IC de 95% (31,76% a 39,71%); grupo C teve um índice médio de hiperplasia de 16,21% IC de 95% (13,36% a 19,05%); grupo A teve um índice médio de hiperplasia de 21,12% IC de 95% (17,26% a 25,01%); com P < 0,0001. Sendo assim, o Allium sativum tem a mesma eficácia na inibição da hiperplasia miointimal comparada aos tratados com Cilostazol
72

Segmentace ultrazvukovych snimku za ucelem detekce arterialni steny a mereni vrstev intima-media / The Segmentation of Ultrasound Images for Artery Wall Detection and Intima-Media Thickness Measurement

Beneš, Radek January 2013 (has links)
The thesis focuses on the measurement of intima media thickness, which seems to be a significant marker of the risk of cardiovascular events. Intima media thickness is measured in ultrasound image displaying the common carotid artery in its longitudinal section. In the longitudinal section the intima and media layers are visible. Thesis is discussing both technical and medical background and summarizes state of the art in this field. The main part of the thesis describes the novel automatic system for measurement of intima media thickness. Proposed system includes also robust method for artery localization and therefore is able to process raw B-mode data from ultrasound station without any initialization or manual preprocessing.
73

Cardiovascular Remodeling Relates to Elevated Childhood Blood Pressure: Beijing Blood Pressure Cohort Study

Liang, Yajun, Hou, Dongqing, Shan, Xiaoyi, Zhao, Xiaoyuan, Hu, Yuehua, Jiang, Benyu, Wang, Liang, Liu, Junting, Cheng, Hong, Yang, Ping, Shan, Xinying, Yan, Yinkun, Chowienczyk, Philip J., Mi, Jie 20 December 2014 (has links)
Background/objectives There are few studies investigating the long-term association between childhood blood pressure (BP) and adult cardiovascular remodeling. We seek to examine the effect of elevated childhood BP on cardiovascular remodeling in early or middle adulthood.Methods We used the "Beijing BP Cohort Study", where 1259 subjects aged 6-18 years old were followed over 24 years from childhood (1987) to early or middle adulthood (2011). Anthropometric measures and BP were obtained at baseline and follow-up examinations. Carotid-femoral pulse wave velocity (cfPWV), carotid intima-media thickness (cIMT), and left ventricular mass index (LVMI) were measured to assess cardiovascular remodeling in early or middle adulthood. Multiple logistic regression models were used to assess the odds ratio (OR) and 95% confidence interval (CI) for cardiovascular remodeling.Results 82 out of 384 children with elevated BP (21.4%) had adult hypertension. Compared to those with normal BP, children with elevated BP were at 2.1 times (95% CI: 1.4-3.1) likely to develop hypertension in early or middle adulthood. Compared to those with normal BP, children with elevated BP were at higher OR of developing high cfPWV (OR = 1.8, 95% CI = 1.3-2.4), high cIMT (1.4, 1.0-1.9), or high LVMI (1.4, 1.0-1.9) in early or middle adulthood. The ORs for remodeling (for any measures) were 1.4 (0.9-2.0) in early adulthood for children age 6-11 years, and 1.6 (1.1-2.4) in middle adulthood for those aged 12-18 years.Conclusions Children with elevated BP from 6 years old have accelerated remodeling on both cardiac and arterial system in early or middle adulthood.
74

”På ett vis är det naturligt, men ändå lite känsligt” - En intervjustudie av förskollärares förhållningssätt till barns sexualitet och intima kroppsdelar

Jinnevik, Amanda, Larsson, Elin January 2020 (has links)
Med utgångspunkt i samhällets problematik av ökande sexualbrott, och barns sexualitet som tabubelagt ämne, har vi formulerat studiens syfte. Vi syftar på att om barns sexualitet lyfts tidigt på ett positivt sätt utvecklar barn en sund syn på sexualitet i framtiden. Således vill vi undersöka hur förskollärare förhåller sig till, samt arbetar med, barns sexualitet och syn på sina intima kroppsdelar i förskolan. Studiens teoretiska referensram bygger på Foucaults makt- och diskursbegrepp samt Freuds psykoanalytiska teori. Vår undersökning utgår från en kvalitativ metod med semistrukturerade intervjuer av fem förskollärare. Studiens resultat visar att barns sexualitet uttrycks i relation till naturligt och onaturligt, dels indirekt dels direkt i tal. Resultatet visar även att förskollärarna endast arbetar med barns sexualitet i förskolan om barnen själva initierar det samt beroende på vad för sorts sexuella aspekter det handlar om. Det kan även utläsas i resultatet att förskollärarna lyfter föräldrar-, kultur- och åldersaspekter som möjligt hinder i avseende deras arbete med barns sexualitet. Slutligen visar resultatet att arbetslagets funktion samt litteraturen är två delar som framförs centrala av förskollärarna i deras arbete med barns sexualitet.
75

Effects of Acute and Chronic Low-Volume High-Intensity Interval Exercise on Cardiovascular Health in Patients with Coronary Artery Disease

Currie, Katharine D. 04 1900 (has links)
<p>The merits of low-volume high-intensity interval exercise (HIT) have been established in healthy populations; however, no studies have examined this exercise prescription in patients with coronary artery disease (CAD). The present thesis examined the acute and chronic effects of HIT in patients with CAD.</p> <p>The first study demonstrated transient improvements in brachial artery endothelial-dependent function, assessed using flow-mediated dilation (FMD), 60-minutes following a single bout of either HIT or moderate-intensity endurance exercise (END) in habitually active patients. The second study demonstrated no effects of training status on the acute endothelial responses to exercise; following 12-weeks of either HIT or END training. However, there was a significant reduction in endothelial-independent function immediately post-exercise, at both pre- and post-training, which requires further examination. The third study demonstrated comparable increases in fitness and resting FMD following 12-weeks of END and HIT, lending support to the notion that favorable adaptations are obtainable with a smaller volume of exercise. Lastly, the fourth study demonstrated no change in heart rate recovery following 12-weeks of END and HIT. However, pre-training heart rate recovery values reported by our sample were in a low risk range, which suggests training induced improvements may only be achievable in populations with attenuated pre-training values.</p> <p>The results of this thesis provide preliminary evidence supporting the use of HIT in patients with CAD. The findings of favorable transient and chronic improvements following HIT are notable, especially given the HIT protocol involves less time and work than END, which was modeled after the current exercise prescription in cardiac rehabilitation. Further investigations are necessary, including the assessment of additional physiological indices, the feasibility and adherence to HIT, the inclusion of CAD populations with co-morbidities including heart failure and diabetes, as well as other forms of HIT training including HIT combined with resistance training.</p> / Doctor of Philosophy (PhD)
76

IMPACT OF SIX MONTHS OF EXERCISE TRAINING ON SUBCLINICAL INFLAMMATION AND ENDOTHELIAL FUNCTION

Veerabhadrappa, Praveen January 2012 (has links)
Purpose: Evidence has accumulated to show that elevated subclinical inflammation and impaired endothelial function has been associated with higher risk of cardiovascular disease (CVD). Despite data on these emerging risk factors, scant attention has been paid to: (1) the interactions of inflammation with endothelial function in relatively healthy African Americans; and (2) the efficacy of non-pharmacologic treatment modalities, such as exercise training, on inflammation and endothelial function. The aim of study 1 was to assess the levels of inflammatory markers, to assess the endothelial function in asymptomatic African Americans. The aim of study 2 was to determine the effects of six-months of exercise training on inflammatory markers and endothelial function in the same cohort. Methods: We recruited 79 African Americans who were sedentary, non-diabetic, non-smoking, and free of CV and renal disease. Before and after 6-month AEXT intervention, inflammatory markers (CRP, TNF-a and IL-6) were measured. Right brachial artery diameter was assessed at rest, during flow-mediated dilation (FMD), and after nitroglycerin-mediated dilation (NMD). Peak dilation was calculated as a measure of FMD and NMD, and the FMD/NMD ratio was calculated as a measure of endothelial function normalized by smooth muscle function. Fasted blood samples were obtained and were analyzed for the metabolic profile. Results: In study 1, the mean CRP for the group was 3.3 ± 0.3 mg/L which falls in the high-risk CRP category as per AHA/CDC guidelines. When divided into tertiles for CRP, low-risk (CRP 3 mg/L); VO2max was significantly higher in the low-risk category compared to average-risk category (P =0.004), and significantly higher in the low-risk category compared to high-risk category (P <0.001). Further, Cardiorespiratory fitness was significantly correlated with CRP (Figure. 1; r = -0.456, P <0.001) and BMI (r = -0.362, P = 0.002). CRP was correlated with BMI (r = 0.424, P <0.001). In a multivariable regression model that included age, gender, BMI, CVD risk factors (total cholesterol, triglycerides, HDL lipoprotein, LDL lipoprotein, plasma glucose, BP, and CRP), the following variables were significantly associated with fitness: fitness [B-coeff = -0.434 ± 0.05 (SE), P <0.001] independently predicted CRP. Fitness explained 22% of variance in CRP levels. In study 2, 6-month AEXT intervention significantly increased VO2max, (P=0.001), indicating that the prescribed exercise program may have been sufficient to elicit improvements in cardiovascular fitness. Significant reductions were observed for CRP (P =0.014). On repeated measures ANCOVA, the mean CRP values were significantly different (F (1,32) =6.703, P=0.014) between before vs. after training (Mean ± SEM; 3.1 ± 0.4 mg/L vs. 2.4 ± 0.4 mg/L), after adjusting for changed variables (BMI, mean BP and VO2max) as covariates. For endothelial measures, significant increase in endothelial function were observed for %FMDpeak (P =0.043) [Figure. 22] and FMD/NMD Ratio (P =0.047) increased post-AEXT. On repeated measures ANCOVA, the mean %FMD was statistically significantly different (F (1,16) =5.582, P=0.031) between before vs. after training (Mean ± SEM; 6.4 ± 2.6% vs. 9.4 ± 2.1%), after adjusting for changed variables (BMI, total-cholesterol and C-reactive protein) as covariates. Conclusions: The results from study 1 provide evidence of the prevalence of high levels of inflammation in the putatively healthy cohort of African Americans. When the group was categorized into tertiles for CRP and the cardio-metabolic, clinical and vascular profiles assessed, statistically significant differences, and rising trends were observed for CRP, body weight, BMI, BBF%, VO2max, SBP and DBP among the three CRP categories indicating a subclinical high cardiovascular risk profile in this cohort of putatively healthy population. Study 2, showed statistically significant improvements in inflammatory marker (CRP) and vascular measures (%FMDpeak, FMD/NMD Ratio and IMT); metabolic profile (triglycerides and FBS); clinical parameters (weight, BMI); cardiorespiratory fitness (VO2max). As we hypothesized, a marked reduction in CRP (-13.5%) post-AEXT was noticed, independent of change in(BMI, MAP and VO2max). Further, baseline CRP and BMI predicted change in CRP on regression analysis. Next, a marked increase in vascular measures, %FMDpeak (23.9%), FMD/NMD Ratio (25.4%) and IMT (-7.4%) were noticed independent of Ä(BMI, total cholesterol, MAP and VO2max). This may suggest: 1) the dominant anti-inflammatory role of exercise training. 2) that long-term exercise training improves clinical vascular measures in our cohort. / Kinesiology
77

Obesidade, saúde metabólica e sua associação com a espessura íntima-média carotídea e calcificação coronariana / Obesity, metabolic health and their association with carotid intima-media thickness and coronary calcification

Quintino, Carla Romagnolli 31 January 2019 (has links)
Introdução: A obesidade aumenta o risco da presença de alterações metabólicas, o que contribui para um elevado risco cardiovascular. No entanto, o papel independente da obesidade na gênese da aterosclerose e da doença cardiovascular ainda é controverso. Diversos estudos identificaram indivíduos que apresentam um fenótipo de obesidade sem alterações metabólicas, conhecida como \"obesidade metabolicamente saudável\" (ObMS). Como a definição de ObMS é variável, sua prevalência não é bem definida. A espessura íntima-média carotídea (EIMC) e a calcificação arterial coronariana (CAC) são considerados marcadores precoces de aterosclerose subclínica Apesar de estudos prévios terem avaliado a associação entre índice de massa corporal (IMC) e EIMC e entre IMC e CAC, o papel independente da obesidade, particularmente em indivíduos metabolicamente saudáveis não está claro. Objetivos: Avaliar se a obesidade, independentemente dos fatores de risco cardiovascular, está associada à maior EIMC e à maior CAC. Calcular a prevalência de ObMS utilizando uma definição estrita de saúde metabólica. Métodos: Este estudo é uma análise transversal dos dados da linha de base do Estudo Longitudinal da Saúde do Adulto (ELSA-Brasil). O indivíduo foi classificado como tendo ObMS se tivesse o IMC >=30 kg/m2 e não tivesse nenhum dos componentes da síndrome metabólica, excluindo-se o critério da circunferência abdominal. Resultados: A análise com EIMC incluiu 10.335 participantes e a análise com CAC incluiu 4.320 participantes. A prevalência de obesidade foi de 21,2% (n=2.191) na análise com EIMC e de 24,3% (n=1.050) na análise com CAC. Com uma definição estrita, a prevalência de ObMS foi de 5,6% na análise com EIMC e 5,5% na análise com CAC. A estratificação dos indivíduos de acordo com a saúde metabólica, evidenciou que os indivíduos metabolicamente saudáveis eram mais jovens, predominantemente mulheres e que tinham menor circunferência abdominal. A maioria dos indivíduos com ObMS tinha obesidade grau 1 (84,7% na análise com EIMC e 82,8% na análise com CAC) e raramente tinham obesidade grau 3 (3,2% na análise com EIMC e 5,2% na análise com CAC). A obesidade abdominal foi presente em mais de 99% dos indivíduos obesos. A análise com EIMC evidenciou que a EIMC média da amostra foi de 0,81 mm (±0,20). A EIMC média da subamostra metabolicamente saudável foi de 0,70 (±0,13) mm nos indivíduos não obesos e de 0,76 mm (±0,13) nos obesos (p < 0,001). A EIMC média da subamostra metabolicamente não saudável foi de 0,81 (±0,20) mm nos indivíduos não obesos e de 0,88 mm (±0,20) nos obesos (p < 0,001). Estes achados se mantiveram inalterados mesmo após o ajuste multivariado para possíveis variáveis de confusão. A análise com CAC (CAC=0 versus CAC > 0) não evidenciou diferença significativa de calcificação coronariana nos indivíduos obesos, metabolicamente saudáveis ou não, em relação aos não obesos. Conclusão: Utilizando-se uma definição estrita, a prevalência de ObMS é menor do que 6%. O conceito de obesidade metabolicamente saudável, mesmo utilizando-se uma definição estrita, parece inadequado, visto que nesta população, a obesidade está associada com valores mais elevados de EIMC. Na análise com CAC não evidenciamos diferença estatisticamente significativa / Introduction: Obesity increases the risk of metabolic abnormalities, which contributes to elevated cardiovascular risk. However, the independent role of obesity in the development of atherosclerosis and cardiovascular disease is still debatable. Several studies identified individuals with an obesity phenotype without metabolic abnormalities: \"metabolically healthy obesity\" (MHO). Since the definition of MHO is variable, the prevalence of MHO varies widely. Carotid intima-media thickness (CIMT) and coronary artery calcification (CAC) are considered early markers of subclinical atherosclerosis. Although previous studies have evaluated the association between body mass index (BMI) and CIMT and between BMI and CAC, the independent role of obesity, particularly in metabolically healthy subjects, is still unclear. Objectives: This study sought to evaluate whether obesity, regardless of cardiovascular risk factors, is associated with higher CIMT levels and higher CAC. We also sought to calculate MHO prevalence using a strict definition of metabolic health. Methods: This is a cross-sectional analysis of the baseline data of Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). MHO was defined as BMI >=30 kg/m2 and none of metabolic syndrome components, excluding waist circumference criterion. Results: EIMC analysis included 10,335 subjects and CAC analysis 4,320 subjects. Obesity prevalence was 21.2% (n=2,191) in EIMC analysis and 24.3% (n=1,050) in CAC analysis. This study showed a prevalence of MHO: 5.6% (n=124) in EIMC analysis and 5.5% (n=58) in CAC analysis. When individuals were stratified according to the presence of metabolic health, we found that metabolically healthy subjects were younger, more likely to be women and had lower waist circumference. Most of the MHO subjects had grade 1 obesity (84.7% in EIMC analysis and 82.8% in CAC analysis) and rarely had grade 3 obesity (3.2% in EIMC analysis and 5.2% in CAC analysis). Abdominal obesity was present in more than 99% of obese subjects. EIMC analysis showed that mean CIMT of the sample was 0.81 (±0.20). The mean CIMT of metabolically healthy subsample was 0.70 (±0.13) in non-obese and 0.76 (±0.13) in obese (p < 0.001). The mean CIMT of metabolically unhealthy subsample was 0.81 (±0.20) in non-obese and 0.88 (±0.20) in obese (p < 0.001). Those findings remained essentially unchanged after multivariate adjustment for confounding. CAC analysis (CAC=0 versus CAC > 0) did not show a significant difference in coronary calcification in obese subjects, regardless metabolic status, when compared with non-obese subjects. Conclusion: Using a strict definition, the prevalence of MHO is below 6%. The concept of MHO, even with strict definition, seems inadequate, as even in this population obesity is associated with higher CIMT levels. CAC analysis did not show statiscally significant difference
78

Die Hämodynamik von femoro-cruralen Bypasanastomosen

Rösler, Stefan K. 18 April 2007 (has links)
Die moderne Gefäßchirurgie bedient sich bei hohen Stadien der pAVK, spezieller Gefäßrekonstruktionen in Form von distalen End-zu-Seit-Gefäßanastomosen. Das langfristige Versagen der Gefäßanastomose hängt primär von der Entstehung einer subendothelialen Intimahyperplasie (IH) ab. Diese IH-Gebiete befinden sich je nach Anastomosengeometrie im Gebiet der Hauben- und Fersenzone sowie am Boden der Anastomose. // Mit Hilfe der Particle Image Velocimetry-Technik wird eine Taylor-Patch-, eine Miller-Cuff-Anastomose und eine femoro-crurale Patch-Prothese bezüglich ihrer Flussmuster sowie ihrer hämodynamischen Eigenschaften wie Geschwindigkeit, Scherstress und Rotation in z-Richtung (Vorticity) untersucht. // In einem hydrodynamischen Kreislaufmodell werden elastische, transparente Silikonmodelle der Anastomosen hergestellt und mit einem blutanalogen Newtonschen Fluid (Glycerol-Wasser-Gemisch) unter Simulation der femorocruralen Druckkurve, pulsatil bei Variation der Strömungsbedingung perfundiert. Der periphere Widerstand beträgt 0,5 mmHg/ml/min (PRU) und die Phasenverschiebung -12 Grad (zwischen Druck- und Flusskurve). // Die Flussmuster variieren zwischen den unterschiedlichen Ausstromverhältnissen erheblich. Bei den unterschiedlichen Flussstärken hingegen ähneln sich die Flussmuster. Alle drei Modelle zeigen ausgeprägte Flussseparationszonen im Hauben- und Fersengebiet sowie geometrieabhängig auch eine Stagnationszone am Boden. Diese Bereiche wiesen die geringsten Fluidgeschwindigkeiten, deutlich unter normalem Wandscherstressniveau liegende Scherstressverhältnisse sowie geringe Vorticitywerte auf. Im Bereich der Übergangszonen finden sich hohe Scherstress- sowie Vorticitywerte. Geschwindigkeitsunterschiede des Fluids zeigten sich im Bereich der Ausstromsegmente. Variable Stressverteilungen zeigen sich auch innerhalb der Separationszonen. Eine Erklärung für die unterschiedlich beschriebenen Offenheitsraten der drei Anastomosenformen wird durch diese Arbeit nicht gefunden. / Modern vascular surgery uses special termino-lateral anastomoses for treating high levels of peripheral arterial disease (PAD). Long term stenoses and occlusions of vascular anastomoses mostly depend on the development of subendothelial myointimal hyperplasia (MIH). There are characteristic areas within the anastomoses, where this process can be examined: The heel, the tow and the floor zone. // This examination observes local hemodynamics like velocity, shear stress and vorticity (rotation in z-direction) and flow patterns of a Taylor-Patch-, a Miller-Cuff-Anastomosis and a feroro-crural patch prothesis (FCPP) with the usage of a Particle Image Velocimetry. In a hydrodynamic circulation model various elastic, transparent silicon phantoms of termino-lateral anastomoses are perfused with a Newton fluid blood analogon (glycerol-water mixture) while simulating the femorocrural pressure curve in a pulsatile manner under variation of the flow conditions. The outflow resistance is 0.5 mmHg/ml/min (PRU, peripheral resistance units) and a phase shift of -12° between flow and pressure curve is simulated. // The flow patterns differed extremely in accordance of the various outflow ratios. Using different flow intensity, the flow patterns are very similar. // All three anastomoses show characteristic heel and toe separation zones. In the FCPP centre a stagnation zone on the floor can not be examined. Shear stress inside the flow separations was significantly lower than normal wall shear stress. High shear stress levels were found inside the transition zones between flow separation and high velocity mainstream. An explanation for the different stenoses and occlusions time of the three different anastomoses can not be found.
79

Relação entre o grau de prejuízo da circulação periférica, a espessura íntima-média carotídea e a função cognitiva de pacientes com doença arterial periférica / Association between degree of impairment of peripheral circulation, carotid intima-media thickness and cognitive function in patients with peripheral arterial disease

Ferreira, Naomi Vidal 07 May 2014 (has links)
INTRODUÇÃO: A Doença Arterial Periférica dos membros inferiores (DAP) é um acometimento relacionado à obstrução arterial desses membros, causada pela doença aterosclerótica, uma doença sistêmica. Por essa razão, a DAP costuma associar-se ao aumento da espessura íntima-média (EIM) carotídea e ao prejuízo cognitivo. No entanto, não se sabe qual o papel da EIM no prejuízo cognitivo observado na DAP. OBJETIVOS: Avaliar as funções cognitivas de pacientes com DAP, associá-las ao grau de prejuízo da circulação periférica e avaliar o papel da EIM nessa associação. CASUÍSTICA E MÉTODO: Foram selecionados 26 pacientes com DAP (68,57+8,34 anos; 65,4% do sexo masculino) e 40 indivíduos-controle (67,17+8,24 anos; 62,5% do sexo masculino). Todos participantes foram submetidos a uma avaliação sócio-demográfica, que coletou dados de caracterização do indivíduo e antecedentes clínicos; a uma investigação clínica, composta pela avaliação do índice tornozelo-braquial (ITB), pela medida da espessura íntima-média (EIM) carotídea, e pelo teste de caminhada de seis minutos (TC6\'); e a uma avaliação neuropsicológica, que consistiu nos seguintes instrumentos: Vocabulário (WAIS-III), Cubos (WAIS-III), Dígitos (WAIS-III), Wisconsin Card Sorting Test (WCST), Stroop Color Word Test (SCWT), FAS (COWAT), Animais (COWAT), Teste do Desenho do Relógio e Mini-Mental State Examination (MMSE). RESULTADOS: O grupo DAP apresentou pior desempenho na memória verbal tardia, na amplitude da atenção, na memória operacional, na atenção, no grau de abstração, na flexibilidade mental, na velocidade de processamento da informação, no controle inibitório/impulsividade, no vocabulário, na fluência verbal fonêmica, na fluência verbal semântica, na praxia construtiva e na função cognitiva global em relação ao grupo controle. Após ajuste para escolaridade, nível sócio-econômico, QI e sintomas psiquiátricos, o desempenho do grupo DAP se manteve pior na flexibilidade mental e na fluência verbal fonêmica. O grau de prejuízo da circulação periférica, avaliado pelo ITB, apresentou associação com a memória visual tardia, com a memória operacional, com a atenção, com o grau de abstração, com a velocidade de processamento da informação, com o controle inibitório/impulsividade, com o vocabulário, com a fluência verbal fonêmica e com a função cognitiva global. Após ajuste para escolaridade, nível sócio-econômico, QI e sintomas psiquiátricos, o ITB manteve associação com a fluência verbal fonêmica. Após ajuste para EIM, o ITB manteve associação com o vocabulário. CONCLUSÃO: O grupo de pacientes com DAP apresentou desempenho cognitivo prejudicado, quando comparado ao grupo controle, independente de escolaridade, nível sócio-econômico, QI e sintomas psiquiátricos. O grau de prejuízo da circulação periférica associou-se ao desempenho cognitivo, mas a EIM carotídea pareceu exercer um papel importante nessa associação / BACKGROUND: Peripheral arterial disease of the lower limbs (PAD) is related to arterial obstruction of these limbs, caused by atherosclerosis, a systemic disease. Therefore, PAD is usually associated with increased carotid intima-media thickness (IMT) and cognitive impairment. However, the role of IMT in cognitive impairment observed in PAD is unknown. OBJECTIVES: To evaluate the cognitive functions of patients with PAD, to associate them with the degree of impairment of peripheral circulation and to evaluate the role of IMT in this association. METHODS: 26 patients with PAD (68.57+8.34 years, 65.4% male) and 40 control subjects (67.17+8.24 years, 62.5 % male) were selected. All participants underwent a socio-demographic assessment, which collected data on individual\'s characteristics and medical history; a clinical investigation, consisting of the evaluation of the ankle-brachial index (ABI), the measurement of carotid intima-media thickness (IMT) and the six-minute walk test (6MWT); and a neuropsychological evaluation, which consisted of the following instruments: Vocabulary (WAIS - III), Block Design (WAIS - III), Digit Span (WAIS - III), Wisconsin Card Sorting Test (WCST), Stroop Color Word Test (SCWT) , FAS (COWAT) Animals (COWAT) , Clock Drawing Test and Mini - Mental State Examination (MMSE). RESULTS: The PAD group scored worse on delayed verbal memory, attention span, working memory, attention, degree of abstraction, mental flexibility, information processing speed, inhibitory control/impulsivity, vocabulary, phonemic verbal fluency, semantic verbal fluency, constructive praxis and global cognitive function compared to the control group. After adjustment for education, socioeconomic status, IQ and psychiatric symptoms, the performance of the PAD group remained worse in mental flexibility and phonemic verbal fluency. The degree of impairment of peripheral circulation, assessed by ABI, was associated with delayed visual memory, with working memory, with attention, with degree of abstraction, with information processing speed, with the inhibitory control/impulsivity, with vocabulary, with phonemic verbal fluency, and with global cognitive function. After adjustment for education, socioeconomic status, IQ and psychiatric symptoms, ABI remained associated with phonemic verbal fluency. After adjustment for IMT, ABI remained associated with the vocabulary. CONCLUSION: The group of patients with PAD showed impaired cognitive performance, when compared to the control group, regardless of education, socioeconomic status, IQ and psychiatric symptoms. The degree of impairment of peripheral circulation was associated with cognitive performance, but carotid IMT appeared to play an important role in this association
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Medida do complexo médio-intimal carotídeo em adolescentes brasileiros do sexo masculino / CAROTID INTIMA-MEDIA THICKNESS IN MALE ADOLESCENTS

Mendes, Fernanda 09 December 2010 (has links)
Made available in DSpace on 2016-03-22T17:26:32Z (GMT). No. of bitstreams: 1 MESTRADO FERNANDA.pdf: 502799 bytes, checksum: ac66c75ef6d7608e98e8cb58e8b514d8 (MD5) Previous issue date: 2010-12-09 / OBJECTIVES: Assess the carotid intima-media thickness (IMT) in a sample of male adolescents in a southern Brazil city, and investigate the association of this measure with biological and demographics variables. METHODS: Cross-sectional study in a random sample of 239 eighteen years old male adolescents, in the Pelotas city military recruitment, in the south of Brazil, held in July 2010. The presence of cardiovascular risk factors was investigated by a questionnaire and physical examination (weight, height, blood pressure and waist circumference). The study was performed in B-mode ultrasound of both common carotid arteries, with IMT measurement in the posterior wall, at a distance of 1.0 to 2.0 cm of the carotid bifurcation. We obtained five measurements of each common carotid and the mean of both sides corresponded to the carotid IMT of each participant. RESULTS: The mean carotid IMT was 0.4969 (± 0.0466) mm and atheromatous plaque were not identified in any adolescent. In the multivariate analysis, BMI (p=0.005) and waist circumference (p<0.001) were positively associated with carotid IMT. CONCLUSION: The association of BMI and waist circumference with the carotid IMT during adolescence shows the importance of adiposity as a cardiovascular risk factor / OBJECTIVES: Assess the carotid intima-media thickness (IMT) in a sample of male adolescents in a southern Brazil city, and investigate the association of this measure with biological and demographics variables. METHODS: Cross-sectional study in a random sample of 239 eighteen years old male adolescents, in the Pelotas city military recruitment, in the south of Brazil, held in July 2010. The presence of cardiovascular risk factors was investigated by a questionnaire and physical examination (weight, height, blood pressure and waist circumference). The study was performed in B-mode ultrasound of both common carotid arteries, with IMT measurement in the posterior wall, at a distance of 1.0 to 2.0 cm of the carotid bifurcation. We obtained five measurements of each common carotid and the mean of both sides corresponded to the carotid IMT of each participant. RESULTS: The mean carotid IMT was 0.4969 (± 0.0466) mm and atheromatous plaque were not identified in any adolescent. In the multivariate analysis, BMI (p=0.005) and waist circumference (p<0.001) were positively associated with carotid IMT. CONCLUSION: The association of BMI and waist circumference with the carotid IMT during adolescence shows the importance of adiposity as a cardiovascular risk factor

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