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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.
41

Aneurisma da aorta abdominal infra-renal : avaliação ultra-sonográfica em homens acima de 50 anos /

Mello, Flávia Moerbeck Casadei de. January 2003 (has links)
Orientador: Hamilton Almeida Rollo / Resumo: Com o objetivo de avaliar a ocorrência de aneurisma da aorta abdominal infra-renal (AAAIR), estudou-se uma amostra da população masculina do Município de Marília, com idade igual ou acima de 50 anos, no período de 2000 a 2002. Foram avaliados 240 homens por meio da ultrasonografia abdominal (USAb), com média de idade de 65,1 anos (±9,8 anos). A aorta abdominal foi medida no sentido ânteroposterior (AP) e látero-lateral (LL) aproximadamente a 2cm abaixo da artéria mesentérica superior (AMS) e 2cm acima de sua bifurcação. O critério utilizado para considerar aneurisma foi o maior diâmetro encontrado igual ou maior que 3,1cm. Também por questionário, foram avaliados os fatores de risco (tabagismo, sedentarismo, alimentação) e as doenças associadas (HAS, DPOC, IM, DM, AOP ou hiperlipidemia). Nos 240 homens, foram encontrados 11 aneurismas, sendo, portanto, a freqüência de 4,6%. Desses 11 aneurismas, 8 mediam entre 3,1 e 4cm (72,7%) e 3, entre 4,1 e 5cm (27,3%). O maior diâmetro da aorta aneurismática foi de 5 cm (sentido AP a 2cm abaixo da AMS). Foi encontrada uma associação significativa entre aneurisma e AOP e DM, não ocorrendo o mesmo com os demais fatores de risco ou outras doenças associadas. A freqüência de aneurisma encontrada em nossa amostra não foi diferente da referida nos estudos populacionais publicados na literatura, o que mostra a importância da doença em nosso meio, e os indivíduos com AOP e DM têm risco maior de desenvolver a doença. / Abstract: In order to evaluate the occurrence of Infra-Renal Abdominal Aortic Aneurysm (AAAIR), a sample of the male population in the city of Marília aged 50 years or older was studied from 2000 to 2002. A group of 240 men with mean age of 65,1 years (±9,8 years) was evaluated through abdominal ultra-sonography examination. The abdominal aorta was measured in the anteroposterior (AP) and in the latero-lateral directions (LL) approximately 2cm below the superior mesenteric artery and 2cm above its bifurcation. The largest diameter equal or larger than 3.1cm found was the criterion used for aneurysm. Risk factors such as smoking, eating, and exercise habits and associated diseases (systemic arterial hypertension, chronic obstructive pulmonary disease, myocardial infarction, diabetes mellitus, occlusive peripheral arterial disease, or hyperlipidemia) were also evaluated through questionnaires. Eleven aneurysms were found in the 240 men, which meant a frequency of 4,6%. Out of these 11 aneurysms, 8 measured from 3.1 to 4cm (72,7%) and 3 measured from 4.1 to 5cm (27,3%). The largest diameter of the aneurysmatic aorta was 5cm (AP direction approximately 2cm of the superior mesenteric artery). A significant association between aneurysm and peripheral vascular disease and diabetes mellitus was found. The same did not occur with the other risk factors or other associated diseases. The frequency of aneurysm found in our sample was not different from the frequency mentioned in population studies published in the literature, which shows the importance of the disease in our environment and that patients with peripheral vascular disease and diabetes mellitus have a higher risk to develop the disease. / Mestre
42

Eicosapentaenoic acid prevents the progression of intracranial aneurysms in rats / エイコサペンタエン酸はラットにおいて脳動脈瘤の増大を抑制する

Abekura, Yu 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22827号 / 医博第4666号 / 新制||医||1047(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 井上 治久, 教授 髙橋 良輔, 教授 Shohab YOUSSEFIAN / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
43

Popliteal Artery Aneurysms: Rationale, Technique, and Results of Endovascular Treatment

Ying, Huang, Gloviczki, Peter 01 June 2008 (has links)
Endovascular repair of popliteal artery aneurysms has been used with increasing frequency in recent years. Advocates of the procedure claim a lower rate of complications, early return to work, no change in the quality of life, and long-term patency rates that are as favorable as those following open surgical repair. Unfortunately, data of only 1 prospective randomized study are available, and a recent meta-analysis showed a higher rate of early graft thromboses and more early reinterventions after endograft repair of popliteal artery aneurysms. Open, elective surgical repair with the vein graft has patency rates more than 90% in contemporary series. Current evidence only supports the use of stent grafts in those with high surgical risks and in the elderly.
44

Prediction Model for 3-Year Rupture Risk of Unruptured Cerebral Aneurysms in Japanese Patients / 日本人患者における未破裂脳動脈瘤の3年間の破裂危険性予測モデル

Tominari, Shinjiro 23 March 2016 (has links)
This is the peer reviewed version of the following article: Tominari, S., Morita, A., Ishibashi, T., Yamazaki, T., Takao, H., Murayama, Y., Sonobe, M., Yonekura, M., Saito, N., Shiokawa, Y., Date, I., Tominaga, T., Nozaki, K., Houkin, K., Miyamoto, S., Kirino, T., Hashi, K., Nakayama, T. and for the Unruptured Cerebral Aneurysm Study Japan Investigators (2015), Prediction model for 3-year rupture risk of unruptured cerebral aneurysms in Japanese patients. Ann Neurol., 77: 1050–1059. doi: 10.1002/ana.24400, which has been published in final form at http://dx.doi.org/10.1002/ana.24400. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19585号 / 医博第4092号 / 新制||医||1014(附属図書館) / 32621 / 京都大学大学院医学研究科医学専攻 / (主査)教授 古川 壽亮, 教授 小泉 昭夫, 教授 佐藤 俊哉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
45

Genetic investigation of cerebrovascular disorders : cerebral cavernous malformations and intracranial aneurysms

Verlaan, Dominique Jacqueline. January 2007 (has links)
No description available.
46

Investigating the Impact of Cigarette Smoke on Myeloid Cell Function and Kinetics During the Pathogenesis of Atherosclerosis and Aortic Aneurysm / MYELOID CELL FUNCTION AND KINETICS IN ARTERIAL DISEASE

Thayaparan, Dharneya January 2021 (has links)
Rationale. Cigarette smoking is a well-known risk factor for cardiovascular disease, including arterial diseases such as atherosclerosis and abdominal aortic aneurysm. However, our understanding of how exposure to cigarette smoke impacts arterial disease pathogenesis is not well known. Consequently, this doctoral thesis focuses on understanding the development of atherosclerosis and aortic aneurysm in the context of exposure to cigarette smoke. In particular, since monocytes and macrophage are key immune cells implicated in arterial pathology, this work concentrates on understanding the impact of cigarette smoke exposure on the function and kinetics of monocytes and arterial macrophages. Main Findings. Using a mouse model that combines two clinically relevant risk factors, hyperlipidemia and cigarette smoke, we showed that smoke exposure increases atherosclerosis and induces the spontaneous formation, progression, and rupture of abdominal aneurysms. We also provide experimental evidence that atherosclerosis strongly associates with regions of elastin damage and arterial dilation, suggesting atherogenesis may directly contribute to abdominal aneurysm formation. Given the importance of macrophages in arterial disease, we investigated arterial macrophage heterogeneity and function following exposure to cigarette smoke. We report that cigarette smoke exposure increased the abundance of arterial monocytes and macrophages, whereas heterogeneity was primarily driven by hypercholesterolemia in aneurysmal tissue. Specifically, hypercholesterolemia is associated with an increase in macrophage populations with putative functions in inflammation and tissue remodelling including Trem2 foamy macrophages, inflammatory macrophages, and interferon-inducible macrophages. Moreover, we demonstrated that arterial macrophages play a critical role in elastin fragmentation within the arterial wall of smoke exposed mice. Finally, we investigated the impact of cigarette smoke on kinetic factors that can contribute to arterial macrophage accumulation. We found that, despite increased development of arterial disease, exposure to cigarette smoke is associated with an overall suppression of circulating monocytes and pro-inflammatory cytokines. Using a parabiosis model, we show monocyte recruitment is significantly increased and is likely a key factor contributing to accumulation of arterial macrophages following exposure to cigarette smoke. We also present evidence suggesting that endothelial dysfunction, related to a loss of endothelial nitric oxide synthase, contributes to increased arterial monocyte recruitment following exposure to cigarette smoke. Conclusions and Significance. Overall, we provide evidence that atherosclerosis likely contributes to abdominal aneurysm pathology in a model of cigarette smoke-induced aneurysm formation. We further provide insight into how tobacco smoke promotes arterial disease development through increased local accumulation of arterial macrophages despite suppressed monopoiesis and systemic inflammation. We identify monocyte recruitment and endothelial dysfunction as key factors contributing to the increased accumulation of arterial macrophages, with no overall differences in macrophage heterogeneity, following smoke exposure. In addition to providing insight into the increased risk of arterial disease following exposure to cigarette smoke, this study also provides experimental evidence that atherogenesis can contribute to abdominal aneurysm pathology. Overall, this thesis furthers our understanding of arterial disease pathogenesis and can provide a foundation for further mechanistic or therapeutic focused research aimed at reducing the burden of cardiovascular disease. / Thesis / Doctor of Philosophy (PhD) / Diseases that affect the heart and major blood vessels are one of the leading causes of illness and death worldwide. Atherosclerosis is one such disease caused by the buildup of fatty deposits in the walls of major blood vessels called arteries. This buildup can eventually block the artery and lead to a heart attack or stroke. Abdominal aortic aneurysms are another type of disease that affects arteries. In this case, the walls of the artery grow weak and begin to balloon out until the artery eventually breaks causing severe internal bleeding and death. One of the most important cells involved in the development of atherosclerosis and aneurysms is the macrophage, a type of white blood cell that is an important part of the immune system and found in diseased arteries. Although we know that cigarette smoking is one of the most significant risk factors for developing atherosclerosis and abdominal aneurysms, we do not fully understand why. Therefore, the goal of this thesis project was to investigate how cigarette smoke affects the development of arterial disease with a focus on understanding how it impacts the movement and function of macrophages. Using a mouse model, we found that the development of atherosclerosis and aneurysm are likely related, and also identified ways that exposure to cigarette smoke increases the numbers of macrophages in arteries. This work advances our understanding of how arterial diseases may be related and provides insight into how smoking can increase the risk of developing arterial disease.
47

Increased nitrotyrosine production in patients undergoing abdominal aortic aneurysm repair

Troxler, M., Naseem, Khalid M., Homer-Vanniasinkam, Shervanthi January 2004 (has links)
No / Vascular inflammation is implicated in the pathogenesis of atherosclerosis and abdominal aortic aneurysm (AAA), and is thought to involve reactive species such as the nitric oxide-derived oxidant peroxynitrite. In the present study nitrotyrosine was measured as a stable marker of peroxynitrite production in vivo. Perioperative blood samples were obtained from patients undergoing elective open or endovascular repair of an AAA and from patients with intermittent claudication, smoking aged-matched controls, non-smoking aged-matched controls and non-smoking young healthy controls. Plasma nitrotyrosine was measured by an enzyme-linked immunosorbent assay. The median plasma nitrotyrosine concentration in patients with an AAA (0·46 nmol nitrated bovine serum albumin equivalents per mg protein) was significantly higher than that in patients with intermittent claudication (0·35 nmol; P = 0·002), smoking controls (0·36 nmol; P = 0·001), non-smoking controls (0·35 nmol; P = 0·002) and young healthy controls (0·27 nmol; P < 0·001). Nitrotyrosine concentrations increased during early reperfusion in open AAA repair, but not during endovascular repair. AAA exclusion from the circulation reduced levels to control values (P = 0·001). Patients with an AAA had raised levels of circulating nitrated proteins compared with patients with claudication and controls, suggesting a greater degree of ongoing inflammation that was not related to smoking. Copyright
48

THE ROLE OF APOB-CONTAINING LIPOPROTEINS IN ABDOMINAL AORTIC ANEURYSM

Liu, Jing 01 January 2015 (has links)
Abdominal aortic aneurysm (AAA) is a devastating disease that exhibits permanent lumen expansion typically in the infrarenal aorta. AAA is prevalent among aged population, especially in males. Despite the incidence in women is lower, studies indicate the tortuosity is more severe and aortic rupture risk is higher in women. In most patients, AAA remains asymptomatic until it ruptures leading to sudden and fatal hemorrhage. To date, there is no proven medical therapy that can prevent the expansion or rupture. Human observational studies implicate the presence of AAA is associated with both high plasma low-density lipoprotein-cholesterol (HDL-C) and low plasma high-density lipoprotein-cholesterol (HDL-C) concentrations. To examine the role of specific lipoproteins in development of AAA, angiotensin (Ang) II-induced AAA was firstly determined in apolipoprotein AI deficient (apoAI -/-) mice in both C57BL/6 and LDL receptor deficient (LDL receptor -/-) backgrounds. The deletion of apoAI led to a significant decrease of HDL-C concentrations. However, we were unable to define any exacerbation of AngII-induced AAA in either normo- or hyperlipidemic mice with apoAI deficiency. Next we compared AngII-induced AAA formation using multiple mouse strains with dietary manipulation to generate different severities of hypercholesterolemia. We demonstrated the apolipoprotein B (apoB)-containing lipoproteins promoted the development of AngII-induced AAA. Moreover, ezetimibe administration significantly reduced both apoB-containing lipoproteins and AAA formation. Together, our studies demonstrate that elevated apoB-containing lipoproteins, contribute to the development of AngII-induced AAA. To investigate the role of apoB-containing lipoproteins on established AAA, male LDL receptors -/- mice fed a Western diet were infused with AngII for 4 weeks to induced AAA. Then mice with AAA were stratified into either a group maintained on western diet or switched to a normal diet. AngII infusion was continued for an additional 8 weeks. The diet switch resulted in significantly reduced plasma cholesterol concentrations, which was attributable to the decrease of apoB-containing lipoproteins. We found a profound inhibition of aneurysm progression in diet switched mice associated with attenuated macrophage accumulation and medial thickening. Collectively, our data demonstrate that apoB-containing lipoproteins promote the progression of established AAA.
49

Abdominal Aortic Aneurysm : Epidemiological and Health Economic Aspects

Mani, Kevin January 2010 (has links)
Abdominal aortic aneurysm (AAA) is a common disease that is life threatening when rupture occurs. The aims of this thesis were to study (I) the long-term survival after AAA repair, (II) the cost of repair with open (OR) and endovascular (EVAR) technique, (III) the effect of different statistical methods on interpretation of cost data, (IV) the prevalence of the disease among patients with suspected arterial disease referred to the vascular laboratory, and (V) the cost-effectiveness of selective high-risk screening. Analyses of data from the Swedish vascular registry (Swedvasc), local patient registries, patient records and hospital cost registries form the basis of this thesis. Short- and long-term survival after intact AAA repair improved over the past two decades, despite increasing patient age and rate of comorbidities over time. Compared to a general population adjusted for age, sex and calendar year, the relative 5-year survival was 90% among those surviving repair. While short-term survival improved over time after ruptured repair, relative long-term survival was stable. Despite differences in patient selection and cost structure, the total cost of AAA repair with EVAR and OR was similar in a population based setting (€28,193). There was lack of consistency in the methods used in cost-analysis in the current literature, and p-values were highly dependent on test method. The practice of selective (non-population-based) screening for AAA among patients referred to the vascular laboratory was studied. The prevalence of AAA was 4.2% among male and 1.5% among female patients. AAA was associated with high age and prevalence of arterial stenosis. Of AAAs detected through selective screening, 21.5% had undergone elective repair at 7.5 years follow-up. In a health-economic evaluation, the incremental cost-effectiveness ratio of selective screening was €11,084 per life year gained. In conclusion, survival after intact AAA repair has improved over time, despite changes in case-mix. Results of health economic reports on cost of AAA repair can be highly dependent on patient selection as well as presentation of data and the statistical methods used. Selective screening for AAA among patients referred to the vascular laboratory is cost-effective.
50

Prädiktoren für die Progredienz von Aortenaneurysmen in der Computertomographie / Predictors of aortic aneurysm growth based on computed tomography

Schaaf, Sebastian 30 March 2015 (has links) (PDF)
Das Aortenaneurysma ist eine häufige Erkrankung, welche mit der gravierenden Kompli-kation einer Aortenruptur einhergehen kann. In den letzten 20 Jahren konnten beachtliche kurative Fortschritte erzielt werden, welche u.a. auf die Ergänzung der rein operativen Therapie um endovaskuläre und Hybridverfahren zurückzuführen sind. Dennoch ist die Aneurysmaruptur mit einer außerordentlich hohen Mortalität assoziiert. Die Genese des Aortenaneurysmas ist multifaktoriell bedingt, sodass das Wachstumsverhalten der Aorta als Surrogat des realen Rupturrisikos schwer vorherzusagen ist. Im klinischen Alltag findet überwiegend der maximale Diameter als Größen- und Verlaufsparameter Anwendung, obwohl dadurch den heterogenen Veränderungen der Aorta möglicherweise nicht ausrei-chend Rechnung getragen wird. Ziel der Studie war es, anhand einer CT-gestützten Verlaufsquantifizierung von Aorten-veränderungen Prädiktoren für das Wachstum der Aorta abzuleiten und Wachstumsraten auf Basis unterschiedlicher morphologischer Ausgangsgrößen zu vergleichen. Zwischen den definierten Aortensegmenten konnten signifikante Unterschiede der erho-benen morphologischen Parameter wie beispielsweise der Größe, der Verteilung von Ge-fäßwand und –lumen, der Verkalkung und der Krümmung aufgezeigt werden. Diese Heterogenität ließ sich auch beim Vergleich von thorakalen/abdominalen, aneurysmati-schen/nicht aneurysmatischen und wachsenden/nicht wachsenden Segmenten bestätigen. So waren beispielweise wachsende Aortensegmente initial größer als nicht wachsende (Volumen 82 cm³ vs. 53 cm³, p < 0,00; Diameter 36 mm vs. 30 mm, p< 0,00), unterschie-den sich hingegen aber nicht hinsichtlich der Wandverkalkung (Calcium-Score 894 vs. 842, p = 0,77). Im Verlauf wiesen die wachsenden Segmente unter anderem eine stärkere Zunahme der maximalen Wandstärke (+15 % vs. +4 %, p > 0,00) und eine stärkere Elongationstendenz (Segmentlänge +3,6 % vs. -0,5 %, p < 0,00) auf. Insgesamt konnte gezeigt werden, dass im Verlauf eine Wachstumsdynamik beinahe aller erhobenen Größen bestand. Ein durchschnittliches Wachstum des Aortensegmentvolumens um 5,7 % pro Jahr gezeigt konnte werden. Unter den potentiellen Einflussfaktorenkonnten konnten als relevante Prädiktoren die ma-ximale Wandstärke, die Diameter-Längen-Ratio, die Exzentrizität der Außenzirkumferenz sowie die Risikofaktoren Rauchen und die Einnahme von Kortikoiden identifiziert wer-den. Der Vergleich morphologisch unterschiedlich basierter Wachstumsraten zeigte eine erhebliche Diskrepanz insbesondere zwischen dem Routineparameter maximaler Diameter und dem sensitiveren Volumen. Schlussfolgerung: CT-morphologisch bestimmbare Parameter wie die Wandstärke, das Proportionsmaß Diameter-Längen-Ratio und die Exzentrizität des Gefäßquerschnittes sind Prädiktoren überdurchschnittlichen Aortenwachstums. Die umfassenden routinemäßige Evaluation der Aorta mit Erhebung mehrerer morphologischer Parameter – insbesondere des Volumens – ist notwendig, um das heterogene und multifaktoriell bedingte Wachstum der Aorta suffizient zu erfassen. / Purpose This study aims to identify clinical and CT-morphologic predictors of growth of the native aorta and aortic aneurysms. Material and methods Seventy-three patients (66 ±8.0 years) who underwent two subsequent computed tomography angiographies of the thoracic/thoracoabdominal/abdominal aorta for clinical reasons from 2002 - 2008 were retrospectively included. The mean interval between the CT scans was 1.8 ±0.8 years. The aortic anatomy was divided into 9 segments from sinotubular junction to iliac bifurcation. CT scans were obtained with 16- and 64-slice scanners, all series were analyzed on a commercially available workstation. Beside the collection of information about the past medical history, several morphologic parameters were measured for each segment such as aortic volume, maximum diameter, cross sectional area, surface area, calcification, tortuosity, wall thickness or cross sectional eccentricity. Annual growth rates were calculated for each parameter. Aortic total volume was considered as the standard of reference. Therefore, aortic growth was defined as a growth rate of total volume > 5 %. Multiple regression analysis was conducted to reveal predictors of aortic growth. Results For all segments, average volumes were 65.0 ± 59.0/44.7 ± 39.6/20.3 ± 27.9 cm³ (total/lumen/wall). The annual aortic growth rate of total volume was 5.7 % for all segments. All parameters that represent the initial size of the aortic segments (total and lumen volume, maximum diameter, cross sectional area, surface area) were approved as predictors of aortic growth. Further predictors were wall volume, maximum and minimum wall thickness, diameter length ratio, segmental length and tortuosity index. Among the clinical parameters, smoking, corticosteroid medication and peripheral artery disease were confirmed as aortic growth predictors. Conclusions In clinical routine, most therapeutic decisions a made based on the diameter measurement alone, which might be inappropriate. A comprehensive evaluation of aortic morphology is warranted in the presence of increased aortic size, wall thickness, cross sectional eccentricity, smoking and corticosteroid therapy.

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