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Felter, Pierre-Loïc. "Creating hemodynamic atlas of aorta". Thesis, Linköpings universitet, Avdelningen för medicinsk teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-142863.
Testo completoAbstract (sommario):
Turbulent blood flow is involved in the pathogenesis of several cardiovascular diseases. While it is known that turbulence is present in patients with obstructive disease in the major vessels, the magnitude and impact of turbulence in the normal heart and aorta is still relatively unexplored. Besides, existing analysis method of the blood flow is a labour intensive process and requires excessive amount of time. A method to automatically create hemodynamic atlases has been developed, using 4D Flow magnetic resonance imaging (MRI), a powerful tool to measure blood flow characteristics. The resulting atlases show the expected blood flow characteristics in the aorta for a group of similar subjects. Application of the method in healthy young and healthy old has shown significant differences in kinetic energy and turbulent kinetic energy in the aortic flow.
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Goulart, Gladstone. "Aneurisma de aorta abdominal roto". [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312328.
Testo completoAbstract (sommario):
Orientador: Ana Terezinha GuillaumonDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-07-31T15:08:36Z (GMT). No. of bitstreams: 1 Goulart_Gladstone_M.pdf: 10287445 bytes, checksum: 33d3b6d03f2c487d83f0162600995f42 (MD5) Previous issue date: 2001
Resumo: o presente estudo tem por finalidade estabelecer um programa de atendimento ao paciente do PS com dor abdominal aguda, suspeito de AAAR, para reduzir os graus de morbidade e mortalidade. Foram atendidos no PS do Hospital de Clínicas da Faculdade de Ciências Médicas na Unicamp, de janeiro de 1990 a dezembro de 1995, 23 pacientes com dores abdominais, sendo 20 homens e três mulheres com idade de 44 a 80. Seis pacientes (26,08%) tinham conhecimento da doença e 17 (73,91%) não tinham. Cinco pacientes (22%) foram encaminhados de outros hospitais com diagnóstico equivocado: cólica renal, pancreatite, patologias de coluna vertebral e lombalgia. Foram operados 18 pacientes (78,26%) de urgência e cinco pacientes (21,73%) de emergência. Dos cinco pacientes atendidos na emergência, quatro já tinham feito US, dois com TC e um paciente sem nenhum exame. Na urgência, oito pacientes (34,78%) fIZeramUS e 15 pacientes fizeram Te. Os 23 pacientes foram divididos em dois grupos: os que apresentavam quadro clínico de rotura e que foram atendidos no PS antes de 24h e os que foram atendidos após 24h. Dos 23 pacientes, sobreviveram dez (43,47%) com 56,52% de mortalidade. O infarto agudo do miocárdio foi a patologia que causou maior número de óbitos. A cirurgia para correção do AAAR mostrou que os pacientes atendidos na emergência com evolução clínica de rotura maior que 24h apresentaram melhor sobrevida no pós-operatório que os pacientes com evolução clínica de rotura menor que 24h. Os pacientes atendidos na urgência em comparação com os da emergência apresentaram uma melhor sobrevida no pós-operatório. Assim, conclui-se que quando houver forte suspeita clínica de AAAR, os pacientes devem ser encaminhados imediatamente à sala de operação. O paciente deve ser tratado cirurgicamente antes de transcorridas 24h do primeiro sintoma, considerando que o diagnóstico de AAAR é essencialmente clínico. Os pacientes admitidos no PS, com quadro clínico de abdome agudo devem ser submetidos à laparotomia exploratória, não se esquecendo de que pode ser AAART. Os pacientes com história de AAA serão submetidos à laparotomia para o tratamento da rotura do aneurisma. Os pacientes com mais de 60 anos de idade devem ser submetidos a exame de imagem para avaliar aorta e tratar profilaticamente o aneurisma antes da rotura
Abstract: The present study OOsthe objective of both establishing a nursing in the Emergency room (E.R) for patients suspected, of OOvingruptured abdominal aortic aneurysms (RAAA) and reducing the morbidity and mortality rates. Twenty-three patients with acute abdominal pain were operated on in the emergency room of Clinical Hospital in the Unicamp between January 1990 and December 1995: twenty men and three women with ages varying ftom 44 to 80. Six patients (26,08%) OOdprevious knowledge of their illness and 17 (73,91%) didn't OOveany. Five patients (22%) OOdcome from other hospitaIs with wrong diagnostic: renal pain, pancreatic and vertebral spine pathology. Eighteen patients (78,26%) underwent urgent surgery and five patients (21,73%) were operated on in the Emergency room (E.R). From these, four had already undergone US, two had done CT and one had no exams. In the Urgency room (D.R), eight patients (34,78%) had undergone US and fifteen OOddone CT. The patients were separated in two groups: those who presented clinical characteristics oí ruptured aneurysm and were hospitalized within 24h and the others afier 24h. From the total of 23 patients, 13 did not survive. The acute myocardial infarction was the pathology, which caused high mortality rates. CONCLUSION: l-Surgery to correct RAAA showed that patients were nursed into the Emergency room with clinical evolution of ruptured afier 24h, showed a better post-operative prognosis than patients of ruptured before 24h; 2-The patients were nursed in the Urgency room comparing with those of Emergency room, showed a better prognosis in the post-operative. So, we conclude tOOtwhen there is strong medical suspicion of RAAA, patients must be immediately taken to the operating room; 3-Patients must be surgically treated within 24h ofthe first syrnptoms, considering tOOthe RAAA diagnosis is essentially clinical; 4-Patients taken into the Emergency room, with acute abdominal pain ofunknown cause, must be submitted to a sound surgery, OOvingin mind tOOthe result can be that of a tamponed RAAA; S-Patients with AAA history will OOveto undergo on operation to correct the rupture of the aneurysm; 6-Patients over 60 must OOvethe aorta evaluated through CT or US and the aneurysm prophylatically treated to prevent rupturing. With the achieved results, a proposed protocol was elaborated, translated into the following algorithm: ...Note: The complete abstract is available with the full electronic digital thesis or dissertations
Mestrado
Cirurgia
Mestre em Cirurgia Medica
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Gimpel-Henning, Kristin [Verfasser]. "Auswirkung des Abklemmens der Aorta auf den endothelialen Schaden der Aorta ascendens / Kristin Gimpel-Henning". Lübeck : Zentrale Hochschulbibliothek Lübeck, 2010. http://d-nb.info/1007466995/34.
Testo completo
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Iliopoulos, Jim St Vincent's Clinical School UNSW. "The aortic wrap procedure:a surgical method of treating agerelated aortic dilatation and stiffening". Awarded by:University of New South Wales. St Vincent's Clinical School, 2006. http://handle.unsw.edu.au/1959.4/28217.
Testo completoAbstract (sommario):
Introduction: There is progressive stiffening and dilatation of the aorta and large elastic arteries with aging as a result of the repetitive cyclic stress they are exposed to throughout life. Aortic stiffening has a number of detrimental effects including an increase in aortic pulse wave velocity and early wave reflection, isolated systolic hypertension, ventricular-vascular mismatch, impaired coronary blood flow reserve, and is the fundamental cause of heart failure in the elderly. The aim of this thesis is to provide proof of concept for the aortic wrap procedure; a surgical treatment of stiffening and dilatation of the ascending aorta with aging. The surgical procedure involves wrapping an elastic material around the ascending aorta of elderly patients, to reduce the stiffness and diameter of the ascending aorta towards that seen in youth. Methods: Proof of concept is investigated in the following studies. 1. The effect of the elastic wrap on the in-vivo stiffness of the normal aorta. 2. The effect of the elastic wrap on the in-vivo stiffness of the dilated and stiffened aorta. 3. The effect of the elastic wrap on the in-vitro stiffness of the aged human ascending aorta and on aortic pressure. 4. The effect of wrapping the aged human ascending aorta on pulse pressure (mathematical model). 5. The effect of chronic implantation on the structure of the normal aorta. 6. The mechanical properties of the ovine thoracic aorta and the elastic wrap material. Results: 1. Elastic wrap application increased the in-vivo stiffness of the normal aorta. 2. Elastic wrap application decreased the stiffness of the stiffened and dilated aorta. 3. Elastic wrap application decreased the in-vitro stiffness of the elderly human ascending aorta and pulse pressure. 4. A reduction in ascending aortic stiffness was sufficient to reduce ascending aortic pulse pressure. Conclusion: Application of the elastic wrap to the aged human ascending aorta is expected to reduce aortic stiffness, as well as systolic and pulse pressure, and to increase diastolic pressure with a reduction in cardiac load. The aortic wrap procedure may be an effective surgical procedure for the treatment of heart failure and isolated systolic hypertension.
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Troiano, Jéssica Antonini. "Papel das espécies reativas de oxigênio na hiporreatividade de aortas à fenilefrina observada no final da prenhez de Ratas Espontaneamente Hipertensas (SHR) /". Araçatuba, 2015. http://hdl.handle.net/11449/127836.
Testo completoAbstract (sommario):
Orientador: Cristina Antoniali SilvaBanca: Angelina Zanesco
Banca: Carlos Renato Tirapelli
Resumo: Estudos têm mostrado que em ratas prenhas normotensas ou hipertensas (SHR) há uma diminuição significativa da pressão arterial nos períodos finais da prenhez diretamente associada à redução da atividade simpática perivascular de leitos mesentéricos de ratas normotensas ou hipertensas (SHR). Essas alterações têm sido atribuídas a uma importante participação dos fatores relaxantes derivados do endotélio com destaque ao óxido nítrico (NO). Estudos recentes do nosso laboratório sugerem que o aumento da síntese de NO pela enzima óxido nítrico sintase endotelial (eNOS) ao final da prenhez ocorre por uma via menos dependente de cálcio, associada a fosforilação da eNOS em resíduos de Serina 1177, através da via PI3K/Akt/eNOS. Por outro lado, ratas hipertensas não prenhas apresentam uma disfunção endotelial e vascular ocasionada pelo aumento na produção de espécies reativas de oxigênio (ERO), sendo o complexo enzimático NAD(P)H oxidase, uma importante fonte de ERO. A produção de ERO modula a biodisponibilidade de NO. Assim, uma diminuição das ERO durante a prenhez poderia contribuir para a redução da PA e modulação da reatividade vascular, dependente do endotélio, aos agonistas vasoconstritores. Nossa hipótese é que em SHR prenhas, a redução da produção de ERO na aorta contribuiria para o aumento da biodisponibilidade do NO e para a hiporreatividade de aortas à fenilefrina (PE). Para isso, o estresse oxidativo sistêmico e da aorta (TBARS) foram avaliados em ratas Wistar e SHR, prenhas (P) e não prenhas (NP). Analisamos o efeito hipotensor da Apocinina (30 mg/kg) e do Tempol (30 mg/kg). Anéis intactos de aorta torácica de P e NP foram estimulados com PE antes e após incubação (30 min) com Apocinina (100 μmol/L) ou Tempol (0,1 nmol/L)...
Abstract: Studies have shown that in normotensive or hypertensive pregnant rats (SHR) there is a significant decrease in blood pressure in late pregnancy directly associated with the reduction in sympathetic perivascular activity of mesenteric beds of normotensive or hypertensive rats (SHR). These changes have been attributed to an important role of endothelium-derived relaxing factors especially to nitric oxide (NO). Recent studies in our laboratory suggest that increased synthesis of NO by endothelial nitric oxide synthase (eNOS) in late pregnancy is of a less calcium-dependent pathway associated with phosphorylation of eNOS on serine 1177 through via PI3K/Akt/ eNOS. On the other hand, do not exhibit a pregnant hypertensive rats and the vascular endothelial dysfunction caused by increased production of reactive oxygen species (ROS), the NAD(P)H oxidase enzyme complex, a major source of ROS. The ROS modulate the bioavailability of NO. Thus, a reduction of ROS during pregnancy could contribute to the reduction in blood pressure and modulation of vascular reactivity endothelium-dependent, to vasoconstrictor agonists. Our hypothesis is that in pregnant spontaneous hypertensive rats (SHR), the reduction of ROS production in the aorta contribute to increase the bioavailability of NO and hyporeactivity to aortae phenylephrine (PE). For this reason, systemic oxidative stress and aorta (TBARS) were valued in Wistar and SHR rats, pregnant (P) and non-pregnant (NP). We analyzed the hypotensive effect of Apocynin (30 mg/kg) and Tempol (30 mg/kg). Intact rings of thoracic aorta of P and NP were stimulated with PE before and after incubation (30 min) with apocynin (100 mmol/L) or Tempol (0,1 nmol/L)...
Mestre
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Hueb, João Carlos [UNESP]. "Associação entre placa de aterosclerose em aorta torácica e alterações morfofuncionais cardíacas, em pacientes com acidente vascular cerebral". Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/100789.
Testo completoAbstract (sommario):
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hueb_jc_dr_botfm.pdf: 402586 bytes, checksum: 0363aade5dace29841c7485277d2b0f8 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Placa de aterosclerose em aorta torácica é uma importante causa de acidente vascular cerebral (AVC) e ataque isquêmico transitório (AIT). Sua gênese estaria relacionada com migração, para a circulação cerebral, de trombos e cristais de colesterol que se desprenderiam de placas complexas, localizadas na aorta torácica proximal. Existem várias semelhanças entre a fisiopatologia do desenvolvimento da placa de aterosclerose e a remodelação miocárdica. Por causa disso, formulou-se a hipótese de que a avaliação de pacientes com AVC e AIT, por meio do ecocardiograma transtorácico ((ETT), pode identificar características associadas com risco aumentado de placa de aterosclerose em aorta. Os objetivos desse estudo foram: 1) avaliar a incidência de placa de aterosclerose em aorta torácica de pacientes com história de AVC e AIT prévios, por meio do ecocardiograma transesofágico (ETE); 2) avaliar se existe associação entre a presença dessas placas e sinais de remodelação ventricular, observados por meio do ETT; e, finalmente, 3) analisar os níveis séricos de proteína C reativa de alta sensibilidade (PCRas), nesses pacientes...
Atherosclerosis plaque in the thoracic aorta is an important cause of acute cerebrovascular events. It would be caused by migration of thrombi and cholesterol cristals released from complex plaques, located at the proximalis thoracic aorta, to the cerebral circulation. Because there are several similarities between the physiopathology of atherosclerosis plaque development and myocardial remodeling. We hypothesized that patients with cerebrovascular events, and atherosclerosis plaque have cardiac morpho-functional alterations. The objectives of the present study were: 1) to evaluate the incidence of thoracic aorta artherosclerosis plaques in patients with a previous cerebrovascular events history, by transesophageal echocardiogram (TEE); 2) to evaluate if there is an association between the presence of plaques and signs of ventricular remodeling, observed by means of transthoracic echocardiogram; and, 3) to analyze the high sensitivity C-reactive protein (hs-CRP) seric levels, in those patients. One hundred and sixteen patients (79 male) with a previous... (Complete abstract click electronic address below)
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Fonseca, Alyne Souza Félix. "Transplante de células de medula óssea (BMCs) de camundongos em modelo experimental para o desenvolvimento de aterosclerose: aspectos estruturais, ultraestrutuais e moleculares da aorta". Universidade do Estado do Rio de Janeiro, 2015. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=9524.
Testo completoAbstract (sommario):
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorFundação de Amparo à Pesquisa do Estado do Rio de Janeiro
As células tronco são caracterizadas pela sua capacidade de se diferenciar em várias linhagens de células e exibir um pontente efeito parácrino. O objetivo deste trabalho foi avaliar o efeito da terapia com células da medula óssea (BMCs) na glicose sanguínea, no metabolismo lipídico e remodelamento da parede da aorta em um modelo experimental para aterosclerose. Camundongos C57BL/6 foram alimentados com uma dieta controle (grupo CO) ou uma dieta aterogênica (grupo AT - 60% gordura). Após 16 semanas, o grupo AT foi dividido em quatro sub grupos: grupo AT 14 dias e o grupo AT 21 dias receberam uma injeção de PBS na veia caudal e mortos 14 e 21 dias após respectivamente; grupo AT-BMC 14 dias e AT-BMC 21 dias que receberam uma injeção com BMCs na veia caudal e mortos 14 e 21 dias após, respectivamente. O grupo CO foi sacrificado juntamente com outros grupos. O transplante BMCs reduziu os niveis de glicose, triglicerídeos e colesterol total no sangue. Não houve diferença significativa em relação à massa corporal entre os grupos transplantados e não transplantados, sendo todos diferentes do grupo CO. Não houve diferença significativa na curva glicemica entre os grupos AT 14 dias, AT-BMC 14 dias e AT 21 dias e estes diferentes do grupo CO e do grupo AT-BMC 21 dias. O Qa (1/mm2) foi quantitativamente reduzido no grupo AT 14 dias e AT 21 dias quando comparado ao grupo CO. Este Qa se mostrou elevado no grupo AT-BMC 21 dias quando comparado a todos os grupos. O aumento da expessura da parede da aorta foi observado em todos os grupos aterogênicos, entretanto o aumento da espessura foi significativamente menor no grupo AT-BMC 21 dias em relação ao grupo AT 14 dias e AT 21 dias. A percentagem de fibras elásticas se apresentou significativamente maior no grupo AT 21 dias quando comparado ao CO e AT-BMC 21 dias. Não houve diferença significativa entre o grupo CO e AT-BMC 21 dias. Vacúolos na túnica média, delaminação e o adelgaçamento das lamelas elásticas foram observados nos grupos AT-14 dias e AT-21 dias. O menor número destes foi visualizado no grupo AT-BMC 14 dias e AT-BMC 21 dias. A imunomarcação para alfa actina de músculo liso (α-SMA) e fator de crescimento vascular e endotelial (VEGF) mostrou menor marcação em grupos transplantados com BMCs. A marcação para antígeno nuclear de proliferação celular (PCNA) mostrou-se mais expressiva no grupo AT-BMC 21 dias grupo. Marcação para CD105, CD133 e CD68 foi observada nos grupos AT 14 dias e AT 21 dias. Estas marcações não foram observadas nos grupos AT-BMC 14 dias e AT-BMC 21 dias. Nas eletromicrografias observamos o remodelamento benéfico no grupo AT-BMC14 dias e AT-BMC 21 dias, com a organização estrutural similar ao grupo CO. Vesículas de pinocitose, projeção da célula muscular lisa e a delaminação da lamina elástica interna são observados nos grupos AT 14 dias e AT 21 dias. Célula endotelial preservada, com lamina elástica interna de contorno regular e contínua é observada no grupo CO e nos grupos AT-BMC 14 dias e AT-BMC 21 dias. Como conclusão, os nossos resultados reforçam o conceito de que, em um modelo aterosclerótico utilizando camundongos e dieta aterogênica, a injeção de BMCs melhora os níveis de glicose, metabolismo lipídico e ocasiona um remodelamento benéfico na parede da aorta.
Stem cells are characterized by their ability to differentiate into multiple cell lineages and display the paracrine effect. The aim of this work was to evaluate the effect of therapy with bone marrow cells (BMCs) on blood glucose, lipid metabolism and aortic wall remodeling in mice through the administration of a high fat diet and subsequent BMCs transplantation. C57BL/6 mice were fed a control diet (CO group) or an atherogenic diet (AT group). After 16 weeks, the AT group was divided into four groups: an AT 14 days group and AT 21 days group, that were given an injection of vehicle and sacrificed at 14 and 21 days after, respectively; AT-BMC 14 days group and AT-BMC 21 days group that was given an injection of BMCs and sacrificed at 14 and 21 days after. The CO group was sacrificed along with other groups. The BMCs transplant had reduced blood glucose, triglycerides and total cholesterol. There was no significant difference in relation to body mass between the transplanted groups and non-transplanted groups, with all are different to CO group. There was no significant difference in the glycemic curve between AT 14 days group, AT-BMC 14 days group and AT 21 days group and these are different to CO and the AT-BMC 21 days group. The Qa (1 / mm2) was quantitatively reduced in the AT 14 days group and AT 21 days group when compared to the CO group. This Qa proved high in AT-BMC 21 days BMC compared to all groups. The increased thickness of the aortic wall was observed in all atherogenic groups, but was significantly smaller in group AT-BMC 21 days compared to AT 14 days group and AT 21 days group. The percentage of elastic fibers was significantly higher in the AT 21 days group when compared to the CO and AT-BMC 21 days. There was no significant difference between the CO and AT-BMC 21 days. Vacuoles in the media tunic, delamination and the thinning of the elastic lamellae were observed in AT 14 days group and AT 21 days group. The smallest number of these apresentation were displayed on the AT-BMC 14 days group and and AT-BMC 21 days. The immunostaining for α-SMA and VEGF showed lower in AT-BMC 14 days group and AT-BMC 21 days group. The markup for PCNA appears to be greater in the AT-BMC 21 days group. Marking to CD105, CD133 and CD68 were observed in AT 14 days group and AT 21 days group. These markings were not observed in AT-BMC 14 days group and AT-BMC 21 days group. In electron micrographs observed the beneficial remodeling in AT-BMC 14 day group and AT-BMC 21 days, with the structural organization was similar to the CO group. Vesicles of pinocytosis, projection of smooth muscle cell and delamination of the internal elastic lamina are seen in groups AT 14 days group and AT 21 days group. Endothelial cell preserved, regular and continuous contour in internal elastic lamelae is observed in the CO group, AT-BMC 14 days group and AT-BMC 21 days group. In conclusion, our results support the concept that an atherosclerotic model using mice and atherogenic diet, the injection of BMCs improve glucose, lipid metabolism and causes a beneficial remodeling of the aortic wall.
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Lain, Vinícius Victorazzi. "Avaliação em médio prazo da pressão intra-saco após correção endovascular de aneurisma de aorta abdominal com o uso de sensor sem fio". Florianópolis, 2010. http://repositorio.ufsc.br/handle/123456789/103247.
Testo completoAbstract (sommario):
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Ciências Médicas.Made available in DSpace on 2013-07-16T03:50:53Z (GMT). No. of bitstreams: 1 310110.pdf: 339089 bytes, checksum: 73dbf9bdb335a97c9e58214037a9667e (MD5)
Justificativa: O objetivo do tratamento endovascular do aneurisma de aorta abdominal é a exclusão do saco aneurismático da circulação sistêmica. Para acompanhar a eficácia do tratamento é necessária a realização de angiotomografias seriadas. A monitorização continuada da pressão poderia diagnosticar precocemente casos em que esteja ocorrendo falha desse tratamento, auxiliando ou substituindo a tomografia. Objetivo: Avaliar a eficácia em médio prazo da medida de pressão através de sensor sem fio implantado no saco aneurismático após tratamento endovascular de aneurisma de aorta abdominal (AAA). Desenho do Estudo: Quarenta pacientes submetidos a tratamento endovascular de aneurisma de aorta abdominal receberam implante de sensor sem fio para monitorização em médio prazo da pressão intra-saco. Os dados foram analisados no primeiro, sexto, décimo segundo meses e anualmente. A cada análise, uma angiotomografia informava o diâmetro do aneurisma, presença e tipo de vazamento. A pressão arterial sistêmica assim como todos os dados pressóricos obtidos através do sensor foram coletados. Resultados: No seguimento, dos 40 sensores implantados apenas em dois o sinal não pode ser detectado. A pressão de pulso obtida apresentou boa sensibilidade em afastar a presença de vazamento quando inferior a 25mmHg no primeiro ano. Após esse período, o Índice de Endotensão mostra-se como a variável que mais se aproxima dos dados tomográficos. Na presença de vazamantos tipo I ou III, o sensor é capaz de identificar sucesso ou falha após a correção do vazamento. Até o segundo ano de seguimento, resultados apresentados pelo sensor são concordantes com dados tomográficos, a partir daí, perdem acurácia. Conclusão: Na amostra estudada não foi possível obter sensibilidade suficiente para substituir a realização da tomografia no acompanhamento dos AAA tratados por técnica endovascular. Um maior número de pacientes é necessário para estabelecer o verdadeiro papel da monitorização pressórica sem fio no seguimento do tratamento endovascular do aneurisma de aorta abdominal.
Racional: The objective of endovascular treatment of an abdo-minal aortic aneurysm is to exclude the aneurysm sac from systemic circulation. In order to assess treatment effectiveness it is necessary to perform serial computed tomography (CT). Continued pressure moni-toring could provide an early diagnosis of cases in which this treatment is failing, helping or replacing CT. Objective: Evaluation of medium-term effectiveness of pressure measurement using a wireless sensor implanted in the aneurysm sac after endovascular treatment of abdominal aortic aneurysm. Method: Forty patients undergoing endovascular treatment for abdominal aortic aneurysm had a wireless sensor implanted for medium-term monitoring of intrasac pressure. The data were analyzed in the first, sixth and twelfth month and annually. At each analysis, a CT scan in-formed the aneurysm diameter, presence and risk of endoleaks. System-ic arterial pressure was collected, as well as all pressure data obtained through the sensor. Results: Of the 40 sensors implanted, the signal could not be de-tected only in two. The pulse pressure obtained presented good sensitivi-ty to rule out the presence of leakage when it was less than 25mmHg during the first year. After this period, the Endotension Index is the variable that comes closest to the CT scan data. With type I or III endo-leaks, the sensor can identify success or failure after endoleak repair. Until the second year of follow up, the results presented by the sensor agree with CT data, and then become less accurate. Conclusions: In the sample studied sufficient sensitivity could not be achieved to replace the CT when following AAA treated by the en-dovascular technique. A larger number of patients is needed to deter-mine the true role of wireless pressure monitoring when following en-dovascular treatment of abdominal aortic aneurysm.
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Bauer, Matthias. "Bikuspide Aortenklappe und Dilatation der Aorta ascendens". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974923877.
Testo completo
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Eazzetta, Benedict A. "Flow visualization of the human abdominal aorta". Thesis, Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/17800.
Testo completo
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Biadillah, Youssef. "Hemodynamics of an anatomically realistic human aorta". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82469.
Testo completoAbstract (sommario):
Cardiovascular disease (CVD) is North America's leading killer for both men and women among all racial and ethnic groups. Almost 1 million North Americans die of CVD each year, which adds up to 42% of all deaths.Numerous investigations point out that normal blood flow (hemodynamics) is essential to good health and many studies found that there is a relationship between the genesis and the progression of CVD with the locally irregular blood flow occurring in the diseased zones.
The study of hemodynamics in the cardiovascular system is therefore key to the understanding of CVD; its genesis and progression.
The aorta is the largest artery in the body, rising from the heart's major pumping chamber, the left ventricle. It is the primary artery of the circulatory system, delivering oxygenated blood to all other arteries except those of the lungs and is a major site for CVD.
Despite the clinical importance of the aorta, relatively little is known about its hemodynamic features due in part to the difficulty of studying blood flow in this artery.
This thesis presents a numerical analysis on the hemodynamics of a 3D realistic model of the human aorta and its arch reconstructed from Magnetic Resonance Imaging (MRI) data.
The objective was to evaluate the effect of flow waveform and inlet flow velocity profile on the hemodynamics in the proximal, medial, distal regions of the aorta and on the hemodynamics in the branches.
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Rampinelli, Amandio. "Tratamento endovascular do aneurisma da aorta abdominal". Florianópolis, SC, 2000. http://repositorio.ufsc.br/xmlui/handle/123456789/79066.
Testo completoAbstract (sommario):
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde.Made available in DSpace on 2012-10-17T22:48:17Z (GMT). No. of bitstreams: 0
Avaliar a factibilidade e a eficácia do tratamento endovascular com à utilização de endopróteses auto-expansíveis em um modelo experimental de Aneurisma de Aorta Abdominal em cães. Em nenhum dos casos observou-se fuga, migração ou oclusão das endopróteses. O tratamento endovascular dos Aneurismas de Aorta Abdominal em modelo experimental em cães mostrou-se factúvel e eficaz.
13
Bauer, Matthias Dirk. "Bikuspide Aortenklappe und Dilatation der Aorta ascendens". Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2005. http://dx.doi.org/10.18452/13966.
Testo completoAbstract (sommario):
Die bikuspide Aortenklappe gilt als Risikofaktor für das frühzeitige und häufige Auftreten von Aortenklappenvitien, Aneurysmen und Dissektionen. Das Ziel dieser Arbeit ist es, ein begründetes chirurgisches Therapiekonzept für Patienten mit bikuspider Aortenklappe und Dilatation der Aorta ascendens zu entwickeln. Wir analysierten die Daten von 555 Patienten mit bikuspider und 2015 Patienten mit trikuspider Aortenklappe, die sich in unserer Einrichtung einer Operation an der Aortenklappe und/ oder einem Eingriff im Bereich der Aorta ascendens unterzogen. Die Aorta ascendens wurde angiographisch, echokardiographisch und mittels CT auf ihre Konfiguration analysiert und histologisch und histomorphometrisch beschrieben. Auch wurden die Langzeitergebnisse nach Aorta ascendens Reduktionsplastik erfasst. Bei Patienten mit bikuspider Aortenklappe sind mit zunehmendem Durchmesser der Aorta ascendens häufiger die histologischen Zeichen einer Dilatation zu finden. Schwerere strukturelle Veränderungen, insbesondere eine höhergradige zystische Medianekrose, sind nicht zu beobachten. Die Aorta Ascendens Reduktionsplastik zeigt bei Patienten mit bikuspider Aortenklappe und Dilatation der Aorta ascendens gute Langzeitergebnisse. Nur bei Patienten mit nicht optimaler Durchmesser-Reduktion bei der Operation kommt es zu einer späteren Redilatation.The bicuspid aortic valve is a known risk factor for the early and frequent occurrence of aortic valve defects, aneurysms and dissections. This study aims to develop an appropriate surgical therapy concept for patients with bicuspid aortic valve and dilatation of the ascending aorta. The data of 555 patients with bicuspid and 2015 patients with tricuspid aortic valve who underwent surgical treatment of the aortic valve and/or of the ascending aorta at our institution were evaluated. We analyzed the configuration of the ascending aorta by angiography, echocardiography and CT and described the aortic wall by histological and histomorphometric examination. We also analyzed the long-term results after reduction aortoplasty of the ascending aorta. Histological examination of the aortic wall specimens showed that patients with bicuspid aortic valve with increased diameter of the ascending aorta more often have histological signs of dilatation. More severe histological changes such as cystic media necrosis did not occur. Reduction aortoplasty of the ascending aorta shows good long-term results in patients with bicuspid aortic valve and dilatation of the ascending aorta. Only in patients in whom surgical reduction is less than optimal does redilatation occur later.
14
Boufi, Mourad. "Caractérisations morphométriques et biomécaniques de l'aorte thoracique". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM5000.
Testo completoAbstract (sommario):
Objectifs : caractériser (1) la morphométrie de la crosse afin d’examiner les critères favorisant les complications et la faisabilité d’endoprothèses (EP) standards. (2) les propriétés mécaniques de l’aorte ascendante (AA) chez le porc, homme sain et en cas de dissection aortique (DAo).Matériels et méthodes :Caractérisation morphométrique : A partir d’angioscanner aortiques les paramètres: (1) morphométriques élémentaires (2) géométriques ; (3) troncs supra-aortiques (TSAo), sont mesurésCaractérisation mécanique : In vivo : à partir de données échographiques et hémodynamiques, les paramètres élastiques sont calculés.In vitro : tests de traction bi-axiale sur l’AA plus une analyse histomorphométrique et microstructurale.Résultats :Caractérisation morphométrique : > de75% des patients ont une orientation des TSAo à ± 15° par rapport à la moyenne, et une variabilité de la distance entre les ostia TSAo de ± 4 mm.Les facteurs indépendants associés aux endofuites, défaut d’apposition et mal-positionnement sont respectivement:(1) collet proximal court; (2) angulation de la zone d’ancrage (valeur seuil 51°); et (3) indice tortuosité (valeur seuil 1.68) Caractérisation mécanique : In vivo : une grande compliance de l’aorte porcine comparé à l’homme et une rigidification en cas de DAo.In vitro : l’aorte porcine a un comportement linéaire comparé au caractère non linéaire chez l’homme. Conclusion : Ce travail montre :- le lien entre morphométrie et complications après EP, et la faisabilité d’EP standards pour la crosse.- le modèle porcin est inapproprié pour tester les EP de l’AA. - la rigidification de la paroi en cas de DAo influencera le choix des futurs EPObjectives: characterize (1) arch morphometry to examine criteria favoring complications after thoracic endovascular aortic repair (TEVAR) and feasibility of « off-the-shelf » fenestrated devices.(2) mechanical properties of ascending aorta (AA) in swine and humans, with and without aortic dissection.Materials and methods : Morphometric characterization : Computed tomographic angiography were analysed to calculate elementary morphometric, geometric and supra-aortic trunks data Mechanical characterization : In vivo: arterial pressure and diameters measured with echocardiophy are used to calculate elastic parameters.Ex vivo: biaxial tensile testing performed on AA plus histological and microstructural analysis. Results :Morphometric characterization : In > 75% of cases supra-aortic branches are positioned within 15° of each other and distances between them have a variability of ± 4 mm.Independant factors associated with endoleak, bird beak and mis-positioning are respectively : (1) short proximal neck (2) landing zone angulation (cut-off value: 51°); and (3) tortuosity index (cut-off value: 1.68). Mechanical characterization : in vivo: greater compliance of swine aorta compared to humans and a stiffer aorta in case of aortic dissectionBiaxial testing: linear stress-strain behavior of swine aorta, compared to a non linear one in human. Conclusion : our study reveals :- the impact of anatomy on complications occurrence after TEVAR, and suitable arguments for « off-the-shelf » fenestrated devices.- swine model is inappropriate to test AA dedicated stent-graft.- stiffer wall in aortic dissection has consequences on the choice of futur devices dedicated to AA
15
Martinez, Patrícia Alzueta Moreno. "Estudo fenotípico da região Aorta-Gônada-Mesonefros, de embriões de galinhas Gallus gallus domesticus, com ênfase na aorta dorsal". Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5682.
Testo completoAbstract (sommario):
Conselho Nacional de Desenvolvimento Científico e TecnológicoAcredita-se que os primeiros progenitores da hematopoese definitiva surjam da diferenciação do endotélio da aorta dorsal, na altura da região da Aorta-Gônada-Mesonefros (AGM). Com o intuito de estudar esta região e o fenótipo das células do endotélio da aorta dorsal nesta posição topográfica, ovos galados de Gallus gallus domesticus L. foram incubados em chocadeira, classificados em estádios de E16 a E25 e processados histotecnologicamente para obtenção de secções seriadas na altura da região AGM. Estas passaram por coloração por Hematoxilina-Eosina, histoquímica para PAS, PAS-diastase e Alcian Blue pH 1.0 e pH 2.5, histoquímica por lectinas fluoresceinadas e imunofluorescência para moléculas de superfície, citoesqueleto e matriz extracelular. Foi observada hipertrofia endotelial no assoalho da aorta nos estádios observados, o qual se apresentava positivo ao PAS, com ocorrência frequente de vacuolizações basais PAS negativas, e o surgimento ocasional de grupamentos celulares intravasculares. Nestes, as células que se destacavam da membrana basal do endotélio expressavam progressivamente mais material PAS positivo, o qual, no entanto, em nenhum momento pareceu se tratar de glicogênio. Em relação às glicosaminoglicanas, notamos a presença predominante de ácido hialurônico por todo o mesênquima da região e em outras estruturas como periferia da notocorda, tubo neural e mesoderma lateral. Ocorreu co-expressão de fibronectina e α-actina de músculo liso em células circunjacentes à aorta, na face ventral do vaso. GFAP e BMP-4 são expressas entre as células do tubo neural e em sua periferia, assim como na notocorda do embrião. As lectinas Abrus precatorius, Lens culinarise Ricinus communis mostraram-se positivas principalmente na região subedotelial do assoalho da aorta nos estádios observados neste trabalho. Bandeiraea simplicifolia exibiu pouca marcação na aorta dorsal e a Arachis hypogeae foi negativa. Outras estruturas da região AGM também expressaram resíduos de açúcares revelados por estas lectinas, tais como: notocorda, tubo neural, mesênquima, intestino primitivo e saco vitelínico. Estes resultados acrescentam elementos morfológicos e bioquímicos ao conhecimento sobre a região AGM de embriões de galinha e sobre o endotélio, possivelmente hemogênico, da aorta dorsal.
Nowadays it is known that firsts definitive hematopoietic progenitors arise from endothelium differentiation of dorsal aorta, at Aorta-Gonad-Mesonephros (AGM) site. In order to study those events and cells phenotype of dorsal aorta endothelium in this topographical site, fertilized eggs of Gallus gallus domesticus L. were incubated, from E16 to E25 and to be processed by histotechonology to obtain serial sections of the AGM site. After this, they were stained with Hematoxilin-Eosin, histochemistry to PAS, diastase PAS and Alcian Blue pH 1.0 and pH 2.5, to obtain a better overview and characterization from cells, also, histochemistry to fluorescein lectins and immunofluorescense to surface molecules, cytoeskeleton andextracellular matrix were performed. Our results showed endothelial hypertrophy of the aorta floor in the stages analyzed, which shown positive for PAS, with frequent appearance of PAS negatives basal vacuolizations and an occasional intravascular cell clusters arise of. It was also observed that cells which were separated from endothelium basal membrane shown progressively were more PAS positive which however in any time seems to be glycogen. Regard of glycosaminoglycans we noted the main presence of hialuronic acid for all the mesenchymes site and in others structures like notochord periphery, neural tube and lateral mesoderm. It was observed fibronectin and smooth muscle α-actin co-expression on aorta surrounding walls, at vessels ventral face. GFAP and BMP-4 are express between the cells of neural tube and surrounding it, as well as at embryo notochord. The lectins Abrus precatorius, Lens culinaris and Ricinus communis showed mostly positive expression on the sub endothelium site of the dorsal aorta floor at the stages analyzed in this work. Bandeiraea simplicifolia showed low expression on dorsal aorta and in Arachis hypogeae it was negative. Other structures of AGMs site also expressed sugar residues revealed by these lectins like: notochord, neural tube, mesenchyme, primitive gut and yolk sac.
16
Vieira, Gislaine. "Analise da arquitetura da aorta de pacientes hipertensos e normotensos". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310241.
Testo completoAbstract (sommario):
Orientador: Konradin MetzeDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-14T05:10:25Z (GMT). No. of bitstreams: 1 Vieira_Gislaine.pdf: 2072366 bytes, checksum: 051f40f17aea5fcefc3058bc55874b2d (MD5) Previous issue date: 2009
Resumo: Fibras elásticas são componentes essenciais da aorta e remodelamento é acompanhado em muitas doenças e eventos que ameaçam a vida, como dissecção e rupturas. Fibras elásticas podem ser facilmente visualizadas quando coradas com H&E e examinadas por microscopia de fluorescência. Nosso objetivo foi criar um sistema de análise automática da textura das fibras elásticas comparando aorta de pacientes normotensos e hipertensos. O sistema de análise foi composto por Microscópio invertido Olympus IX-81 equipado com scanner FV 300 que utiliza laser FV-5 COMB2, utilizando laser de argônio a 488 nm, objetiva 40x usando óleo de imersão. A espessura da aorta varia de 2 a 3 mm, e a imagem completa foi composta por justaposição de imagens de 220x220 µm utilizando software Fluoview. Para análise foi utilizado o programa gliding box , que é uma caixa deslizadora de 128x128 pixels, que percorre a imagem da aorta pixel a pixel em toda sua extensão. Para análise computadorizada da textura foram utilizados programas computacionais (entropia, homogeneidade local e segundo momento angular derivado da matriz de co-ocorrência de Haralick). Foram calculados e plotados em diagramas resultados equivalentes à topografia histológica da imagem. Em cada caminho o gliding box percorreu entre 2000 e 3000 pixels da textura, revelando a topografia local e sua variação. Foi comparada a textura de fibras elásticas de cortes histológicos corados com HE de 24 pacientes normotensos e 30 hipertensos, adultos de ambos os sexos oriundos de autópsias realizadas no Depto de Anatomia Patológica. Para comparação entre textura e idade utilizou-se Correlação de Pearson, e a textura foi comparada entre os grupos com o auxílio do teste t. Resultados: Tanto nos pacientes normotensos como nos hipertensos não houve correlação entre: número de fibras elásticas ou distâncias entre elas, para as análises de Haralick e idade dos pacientes. No entanto, a entropia em pacientes normotensos (r=0,60; p=0,004) e a homogeneidade local (r=0,43; p =0,049) demonstraram acréscimo da variação topográfica com o envelhecimento, fato que não ocorreu nos hipertensos. Quando comparadas com aortas normotensas, as hipertensas revelaram menos fibras elásticas (p<0,0001), maior variabilidade e distâncias (p<0,0001), aumento da média da espessura e maior variabilidade da espessuras das fibras ( p<0,0001). Conclusão: Demonstramos que o presente método é uma ferramenta que permite uma análise objetiva da textura de fibras elásticas da aorta com a possibilidade de quantificar processos patológicos. Observamos que em pacientes normotensos, o número médio de fibras elásticas e a distância entre elas são constantes e ocorrem discretas alterações da arquitetura com o aumento da idade. Em hipertensos, o distúrbio arquitetural é mais evidente e ocorrem perdas de fibras elásticas.
Abstract: The elastic fiber network is an essential component of the aorta. Its remodeling accompanies many diseases and may provoke life-threatening events, such as dissection or rupture. Elastic fibers can be easily demonstrated in eosin-stained histologic sections examined by fluorescence microscopy. The aim of our study was to create an automatic texture analysis system of the elastic fibers and to apply it in human aortas comparing normotensive and hypertensive patients. The analysis sytem was composed of an Olympus IX-81 inverted microscope, a FV300 scan head and a FV-5 COMB2 laser combiner. The fluorescence of the hematoxylin and eosin-stained slides was excited with the 488 nm line of an Argon laser using a 40x oil immersion objective. The Fluoview software was used to reconstruct the images. The full image of the whole sample (2 or 3mm long) was composed by several 220x220. Then a gliding box of 128x128 pixels was running in 1-pixel steps along a predefined axis parallel to the bottom line of the image. For every new box, computerized analysis of texture features (entropy, local homogeneity and the second angular moment derived from the gray-level co-occurrence matrix) were calculated and plotted in diagrams, where the position on the x-axis was equivalent to the topography in the histologic picture. In that way for each "run" of the gliding box about 2000 to 3000 values of a texture feature were obtained, thus revealing precisely its topographic postion and its variabilty. We compared the elastic fiber texture in routinely HE-stained histologic slides of the aorta ascendens in 24 normotensive and 30 hypertensive adult patients of both sexes and of similar age from our autopsy files. Pearson correlations were calculated between the texture features and the age. Texture features were compared between both groups with the help of the t-test. Results: In normotensive and hypertensive patients no correlations were found between the number of elastic fibers, their thickness or their distance and the Haralick features and the age of the patients. But in normotensive patients entropy (r=0,60; p=0,004) and local homogeneity (r=0,43; p =0,049) showed increasing topographic variations in patients with advanced age, which was not the case for hypertensive patients. When comparing with normotensive aortas, the hypertensive ones revealed less elastic fiber layers (p<0,0001), a greater variabilty of the fiber distance (p<0,0001), increased mean fiber thickness and a greater varaibilty of the fiber thickness( p<0,0001) Conclusion: We showed that the presented method provides a new tool for an objective automatic texture analysis of the elastic fiber texture of the aorta with the possibility of quantification of the disease process. Although in normotensive patients, the mean number and distance of the elastic fibers is constant, discrete local alterations of the architecture appear with increasing age. In hypertensive patients there are more pronounced architectural alterations with loss of the fiber layers.
Universidade Estadual de Campi
Biologia Estrutural, Celular, Molecular e do Desenvolvimento
Mestre em Fisiopatologia Médica
17
Whang, Min Cheol. "Correlation between mechanical and histological measurements in human atherosclerotic aorta". Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/16955.
Testo completo
18
Al-Zobaidy, Mohammed. "Differential actions of methlyarginines in the rat aorta". Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3838/.
Testo completoAbstract (sommario):
The PhD project is about the Regulation of vascular tone by endothelium. It involves studying the effects of methylated arginine analogues such as monomethyl arginine (L-NMMA) and asymmetric dimethylarginine (ADMA) on nitric oxide (NO) activity in rat aorta using organ baths containing Krebs solution at 37 ˚C and gassed with 95% O2 and 5% CO2. These two inhibitors of endothelial nitric oxide synthase enzyme (eNOS) showed an anomalous action, as they inhibited basal NO activity (assessed by enhancement of phenylephrine-induced tone and by blocking relaxations produced by superoxide dismutase or the PDE5 inhibitor; T0156) but not that is stimulated by agonists like acetylcholine or the calcium ionophore A23187. After establishing these findings I will try to find the reason(s) for these paradoxical actions of these two endogenously synthesized inhibitors of eNOS.
19
Rinnström, Daniel. "Coarctation of the aorta : register and imaging studies". Doctoral thesis, Umeå universitet, Institutionen för folkhälsa och klinisk medicin, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126428.
Testo completoAbstract (sommario):
Background Coarctation of the aorta (CoA) constitutes 5-8 % of all congenital heart disease (CHD) and is associated with long-term complications such as hypertension (HTN) and left ventricular hypertrophy (LVH). Factors associated with HTN, LVH, and diffuse myocardial fibrosis, are not yet fully explored in this population. Methods Papers I-III: The Swedish national register of congenital heart disease (SWEDCON) was used to identify adult patients with repaired CoA. Paper IV: Data on 2,424 adult patients with CHD was extracted from SWEDCON and compared to controls (n = 4,605) regarding height, weight and body mass index (BMI). Paper V: Adults with CoA (n = 21, age 28.5 (19.1-65.1) years, 33.3 % female) referred for CMR were investigated with T1 mapping to determine left ventricular extracellular volume fraction (ECV). Results Papers I-II: Out of 653 patients, 344 (52.7 %) had HTN. In a multivariable model, age (years) (OR 1.07, CI 1.05-1.10), sex (male) (OR 3.35, CI 1.98-5.68) and BMI (kg/m2) (OR 1.09, CI 1.03-1.16) were associated with having HTN, and so was systolic arm-leg blood pressure (BP) gradient where an association was found at the ranges (10, 20] mmHg (OR 3.58, CI 1.70-7.55) and > 20 mmHg (OR 11.38, CI 4.03-32.11), in comparison to the range [0, 10] mmHg. When investigating 243 patients with diagnosed HTN, 127 (52.3 %) had elevated BP (≥ 140/90 mmHg). Age (years) (OR 1.03, CI 1.01-1.06) was associated with elevated BP, and so was systolic arm-leg BP gradient in the ranges (10, 20] mmHg (OR 4.92, CI 1.76-13.79), and > 20 mmHg (OR 9.93, CI 2.99-33.02), in comparison to the reference interval [0, 10] mmHg. Patients with elevated BP had more classes of anti-hypertensive medication classes prescribed (1.9 vs 1.5, p = 0.003). Paper III: Out of 506 patients, 114 (22.5 %) were found to have LVH. Systolic BP (mmHg) (OR 1.02, CI 1.01-1.04), aortic valve disease, (OR 2.17, CI 1.33–3.53), age (years) (OR 1.03, CI 1.01–1.05), and HTN (OR 3.02, CI 1.81-5.02), were associated with LVH, while sex (female) (OR 0.41, CI 0.24-0.72) was negatively associated with LVH. Paper IV: There was no difference in height, weight, or BMI between patients with CoA (n = 414) and the reference population. Paper V: In the population of 21 patients, an increased left ventricular myocardial ECV was found in 6 cases (28.6 %). Of the patients with increased ECV, 5/6 (83.3 %) were female (p = 0.002). Patients with increased ECV did not otherwise differ from the rest of the study population. iv Conclusions In adults with repaired CoA, HTN and LVH were common, and many patients with HTN had elevated BP despite treatment. The potentially modifiable factors BMI and systolic arm-leg BP gradient were associated with HTN, and the gradient was also associated with elevated BP among patients with diagnosed HTN. The gradient’s significance remained even within what the current guidelines consider acceptable ranges. Potentially modifiable factors associated with LVH were systolic BP and aortic valve disease. We found no general difference in height, weight, or BMI between patients with CoA and the reference population. While LVH was more common among men, increased myocardial ECV was more common among women.
20
Morandin, Rosana Celestina. "Alterações da aorta em ratas portadoras de neoplasia". [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310253.
Testo completoAbstract (sommario):
Orientadores : Korandin Metze, Rachel LewinsohnTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-07-27T20:34:15Z (GMT). No. of bitstreams: 1 Morandin_RosanaCelestina_D.pdf: 7816307 bytes, checksum: 98964942084f290c6dcfbb012ce6e491 (MD5) Previous issue date: 2000
Resumo: A síndrome da caquexia tumoral é um distúrbio sistêmico muito grave que envolve alterações fisicas e metabólicas, podendo estar presente em até 80% dos portadores de tumor. Muitos órgãos e tecidos não acometidos diretamente pelo tumor podem apresentar alterações graves na síndrome. Os tecidos mais intensamente atingidos são o muscular esquelético e o adiposo. Embora haja uma vasta literatura sobre o assunto, estudos clínicos e experimentais sobre os vasos pré-existentes no hospedeiro são muito raros. Assim, o objetivo desse estudo foi avaliar as possíveis alterações morfológicas e enzimáticas da aorta de ratos portadores uma neoplasia induzida pelo metil-colantreno (Sarcoma), nos estágios mais avançados da doença. Exames bioquímicos e hematológicos foram realizados para avaliar o perfil clínico dos animais. As constantes cinéticas da SSAO (Constante de Michaelis - Km e Velocidade Máxima - Vmax) foram calculadas utilizando-se a benzilamina como substrato. As análises morfológicas das aortas foram feitas através de medidas morfométricas e de estudos de ultraestrutura. Espessura da camada média, densidade de núcleos, diâmetro interno menor, área luminar e número de lâminas elásticas foram quantificadas. Os ratos portadores da neoplasia apresentaram sinais de um desgaste fisico generalizado, com baixo peso, anemia, hipoalbuminemia, hipoglicemia, distúrbios eletrolíticos e acidose metabólica. A V max da SSAO mostrou uma queda estatisticamente significativa de 35%, sem que houvesse diferença detectável no Km. A medida de espessura da camada média da aorta mostrou-se significativamente menor (Controle=50,04 :I:: 2,54 e Sarcoma=38,37:1:: 4,26 Jlm, p
Anatomia Patologica
Doutor em Ciências Médicas
21
Saucedo, Arizaga Roberto. "Patrones Arteriales de la Aorta Abdominal del Conejo". Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2018. http://hdl.handle.net/20.500.11799/69004.
Testo completoAbstract (sommario):
TesisLa angiología es la parte de la anatomía que estudia los órganos de la circulación de la sangre y de la linfa: el corazón y vasos sanguíneos. El sistema cardiovascular está formado de: 1) corazón, 2) arterias, que conducen la sangre hacia los tejidos, 3) capilares, tubos microscópicos de los tejidos y 4) las venas que regresan la sangre hacia el corazón. La estructura básica de la pared de la aorta de los mamíferos es preponderantemente elástica. Las interrelaciones del componente elástico de la pared arterial con colágeno y músculo liso constituyen un "sistema mio-elástico"
22
Saavedra, Ana Margarida Gomes. "Doença aneurismática da aorta abdominal. Diagnóstico e tratamento". Master's thesis, Faculdade de Medicina da Universidade do Porto, 2010. http://hdl.handle.net/10216/61120.
Testo completo
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Романюк, Анатолій Миколайович, Анатолий Николаевич Романюк, Anatolii Mykolaiovych Romaniuk, I. Radomychelski, Микола Сергійович Линдін, Николай Сергеевич Лындин, Mykola Serhiiovych Lyndin et al. "HSP70 overexpression in calcified aorta affected by atheroscleros". Thesis, Springer, 2019. http://essuir.sumdu.edu.ua/handle/123456789/75109.
Testo completoAbstract (sommario):
Background & Objectives: High levels of HSP70 appear to have atheroprotective effect. It was reposted, that antibodies to HSP70 were increased in patients with vascular disease. Also HSP70 levels correlate with lesion severity. Aim of the investigation was to study the HSP70 expression in aortic tissue with calcifications affected by atherosclerosis.
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Parenti, Cristina. "VARIATION OF THE LOCAL MATERIAL PROPERTIES OF AORTA". Master's thesis, Temple University Libraries, 2010. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/70843.
Testo completoAbstract (sommario):
Mechanical EngineeringM.S.E.
Understanding the aortic wall deformation and failure during traumatic aortic rupture (TAR), which is a leading cause of fatality in motor vehicle accidents is of great concern. The specific objective of the present study is to develop a material model that can describe the multi layer nature of the aortic wall. Fundamentally, the aortic wall is composed mainly of three layers, tunica intima, media and adventitia, and they are known to have different structures. Understanding the material properties of these layers is essential in order to study the local mechanisms of deformation, force transmission, and failure. The hypothesis of this study is that the tissue's instantaneous shear modulus grows along the radial direction while moving from the intima toward the adventitia. The higher compliance of the tissue near the intima, which is partly due to the concentration of the smooth muscle cells and partly due to the arrangement of collagen and elastin fibers, can explain the nature of aorta failure which is primarily generated from the inside towards the outer layers. A combination of micro- and nano-indentation tests were used to measure the local material properties of porcine aorta at the length scales of 160 µm and 40 µm respectively. The material properties of aorta were investigated in the lateral (left) region in several longitudinal locations of the descending aorta and the observed viscoelastic behavior was summarized in the form of instantaneous shear moduli and reduced relaxation functions. The instantaneous shear modulus was found to generally increase along the radial direction to about 0.6 normalized radial distance and then became almost constant but with higher variability. The reduced relaxation functions were generally independent of the location and test method. Comparing the mechanical results with the histological results obtained through Van-Guisen staining showed that the material properties are partly related to the distribution of smooth muscle cells. The results of this study can be used to explain the mechanisms of failure in aorta and contribute to improve the computational modeling of aorta's deformation which is valuable in a variety of applications including automotive accidents, endovascular grafts, and angioplasty.
Temple University--Theses
25
Romanov, Vasily Vladimirovich. "MATERIAL PROPERTIES OF AORTA FROM BIAXIAL OSCILLATORY TESTS". Master's thesis, Temple University Libraries, 2010. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/117228.
Testo completoAbstract (sommario):
Mechanical EngineeringM.S.E.
This project addresses characterization of the material properties of aortic tissue. Understanding of these properties is important for a variety of studies including tissue engineering, effects of aging and diseases, stents engineering, and traumatic aorta rupture. The goal of the presented research was to characterize the stress-strain relationship of aorta in dynamic oscillatory biaxial loading. A setup was developed that supplied pressure loading from the physiological to sub-failure levels (between 7 and 76 kPa) to porcine aorta at frequencies ranging from 0.50Hz to 5.00Hz. Samples tested were constrained at both ends while the deformation and the pressure were recorded. Volumetric strain versus pressure was used to characterize the structural behavior of the material which showed frequency dependency and hysteresis indicating viscoelastic response. An offset method was developed to account for drifting behavior exhibited by some of the samples. The structural behavior of aorta was modeled using a quasi-linear viscoelastic (QLV) creep theory. The QLV model included a logarithmic steady state elastic function v = 0.663 +/- 0.040 + 0.241 +/- 0.011 ln(P) for pressure in kPa, and a Prony series creep function ( J0 = 0.472 +/- 0.021, J2 = 0.109 +/- 0.060, J3 = 0.419 +/- 0.056). Modeling results were then used to determine the relationships between the circumferential and longitudinal stresses and strains of the material. The results exhibited that the stress in the transverse direction was about 1.5 times larger than in the axial direction. However, in the axial direction material was stiffer and the deformation was 30% less. The relaxation function of the material was determined by linearizing the non-linear component of the QLV model and applying to it the linear viscoelastic theory. Furthermore, literature comparison revealed that aorta's creep function, as well as its elastic modulus, is within the range of what has been reported in the literature. In conclusion, an experimental model was developed that can be used to predict the behavior of porcine aorta under physiological and sub-failure conditions at quasi-static and dynamic loading.
Temple University--Theses
26
Mandelli, Marcelo Barbosa. "Terapêutica endovascular de aneurismas da aorta torácica descendente". Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/80166.
Testo completoAbstract (sommario):
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Ciências Médicas.Made available in DSpace on 2012-10-18T11:11:09Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T21:54:18Z : No. of bitstreams: 1 191342.pdf: 14433862 bytes, checksum: cc1e66dba5d2378acb9665214916c3b4 (MD5)
Objetivo: Descrever a experiência inicial na utilização da endoprótese ApoloÒ na terapêutica de aneurismas, pseudoaneurismas e dissecções da aorta torácica descendente em humanos.
27
Saavedra, Ana Margarida Gomes. "Doença aneurismática da aorta abdominal. Diagnóstico e tratamento". Dissertação, Faculdade de Medicina da Universidade do Porto, 2010. http://hdl.handle.net/10216/61120.
Testo completo
28
Bičiště, Jan. "Umělá aorta pro demonstraci činnosti intraaortální balonkové kontrapulzace". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218047.
Testo completoAbstract (sommario):
This dissertation work describes design and construction of simulated aorta device intended to demonstrate performance of the intra-aortal balloon catheter (IAB), and to test reaction of the contra-pulsation pump during simulated cardiac output in conditions of tachycardia, bradycardia and arrhythmia. The major part of the device is transparent plastic tube. The pressure pulses (waves) are generated inside this plastic tube to simulate real cardiac output. These pressure pulses are generated by step motor with membrane. The step motor is controlled by programmable control system AMiNi-E. Individual pressure pulses simulate cardiac output in conditions of tachycardia, bradycardia and arrhythmia. Required simulated cardiac output is selected by control switches. Generated pressure pulses are read by pressure sensor and are transferred to the control system of the configuration computer. Read data can be displayed as graphs in program Microsoft Excel. The intra-aortal balloon catheter (IAB) is inserted inside the aorta and is connected with contra-pulsation pump which on pressure pulse is responding.
29
Meirelles, Guilherme Vieira. "Prevalencia de dilatação da aorta abdominal em coronariopatas idosos". [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313438.
Testo completoAbstract (sommario):
Orientadores : Mario Mantovani, Domingo Marcolino BraileDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: O objetivo deste estudo foi a avaliação da prevalência de dilatação da dilatação da aoita abdonünal em pacientes idosos com mais de 60 anos de idade, portadores de coronariopatia aterosclerótica diagnosticada por cineangiocoronariografia corre1acionada com mtores como extensão e gravidade da doença coronariana, presença de lesão arterial obstrutiva dos membros meriores, Diabetis mellitus, hipertensão arterial e tabagismo. Selecionou-se uma amostra de 180 indivíduos portadores de coronariopatia aterosclerótica comprovada por cineangiocoronariografia, com idade igual ou superior a 60 anos. Para a seleção dessa amostra levou-se em consideração o mto de que não tenha sido a indicação do cateterismo a avaliação pré-operatória de cjrurgia vascular. Procedeu-se então a avaliação, baseado na anamnese, exame físico e Doppler ultra-som da aoita abdominal. A análise estatística iniciou-se com o teste Qui-quadrado para avaliar a associação entre as variáveis. A partir das variáveis que apresentaram correlação procedeu-se a análise de regressão logística multivariada para se determinar a influência dos fatores de risco. Com estes dados em mãos, realizou-se a análise de regressão logística univariada considerando significativo um p<= 0,05. Dos 180 pacientes, 31,7% (57) dos casos pertencem ao sexo feminino, e 68,3% (123) ao masculino. A fiUxa etária variou entre 60 e 80 anos com idade média de 66,7 anos. Dos 16 indivíduos portadores de dilatação da aoita abdominal (10 aneurismas e 6 ectasias), apenas um indivíduo do sexo feminino. Dos 40 pacientes diabéticos, 2 (5%), apresentaram dilatação da aorta abdominal. Nos não portadores desta doença a prevalência da dilatação aórtica foi de 10% (14/140) indicando ausência de interação entre ambas doenças (p= 0,7268). A Hipertensão arterial aumentou a freqüência de dilatação da aorta abdominal para 9,4%, comparativamente a 7,5% (4 /53) dos pacientes não hipertensos, todavia esta diferença não foi significante (p= 0,3549). O tabagismo aumentou a prevalência de dilatação aórtica (15%; n=97) comparado aos indivíduos não fumantes (1,2% n=83; p = 0,0128). Os portadores de doença arterial obstrutiva dos membros inferiores apresentaram maior freqüência de di1atação da aorta abdominal (30,8%; n=26) comparado aos 154 indivíduos que não apresentavam doenças arteriais obstrutiva, que apresentaram 5,2% (8 casos) de dilatação aórtica (p = 0,0015). Utilizando-se O modelo de regressão logística mu1tivariada estudou-se a prevalência da dilatação da aorta abdominal com diferentes enfoques, determinando-se assim a probabilidade de se apresentar o evento em cada modelo selecionado. Desta forma o risco para um indivíduo com uma lesão aterosclerótica coronariana de apresentar di1atação da aorta abdominal foi de 0,4% no grupo avaliado. Da mesma forma nos portadores de 2 ou 3 lesões, o risco foi de 1,7%, e naqueles com mais de 3 lesões um risco de 4,5%. Quando associados ao tabagismo, estes valores alteraram-se respectivamente para 6,9%, 11,8% e 27,1 %. Considerando-se o modelo hipertensão e tabagismo, o indivíduo não hipertenso e não fumante apresentou um risco de 0,3%, o bipertenso de 0,67% e o tabagista de 2,3% de ser portador da dilatação da aorta abdominal. Associando-se os dois fatores, o risco sobe para 4,6% e associado à presença de mais de 3 lesões coronarianas, atinge 8,7%. Quando portador de doença arterial obstrutiva dos membros inferiores eleva o risco para 12,3%. O maior risco encontrado foi a associação de tabagismo e presença de doença arterial obstrutiva dos membros inferiores, neste caso o risco estimado é de 30,4%. O presente estudo permite concluir que a prevalência de di1atação da aorta abdominal foi de 8,9% (16 de 180 pacientes) nesta amostra específica. Apresentou-se de forma mais freqüente nos indivíduos do sexo masculino, tabagistas, bipertensos, portadores de doença arterial obstrutiva aterosclerótica dos membros inferiores, e em presença de lesões aterosclerótica difusa das artérias coronárias
Abstract: The aime of this study was to evaluate the prevalence of abdominal aortic dilatation in patients over 60 years old with coronary disease diagnosed by coronarygraphy, reJated to fàctors such as reach and seriousness of the coronarian disease, presence of periferic arterial obstruction lesions, diabetis melitus, arterial hypertension and smoking. The sample selected for the study was made of 180 individuais harbouring coronary disease proven by coronarygraphy. The exam was made at the institute of cardiovascular diseases at São José do Rio Preto and a1l patients were 60 years old or older and the indication of the catetherism was not the pre-operatory evaluation for the vascular surgery. The statistic analysis begun with the Q-square method, to evaluate the association between the variables. From the results, presenting correlation, a multivaried logistic regression method ana1ysis was used to determine the influence of the risk fàctors. An unvaried logistic regression analysis was than made, considering a p <= 0.05 significative. Among the 180 patients, 57 (31.7%) were women and 123 (68.7%) were man. The age was between 60 and 80 years old, with average of 66.7. The 15 cases of dilatation occurred on males with an average age of 69.2 years. Among the 16 individuais with aortic disease (10 aneurysm and 6 dilatation), on1y one was female. From 40 diabetic patients, 2 (5%) had shown aortic di1f1tation, and 14 (10%) of the 140 non-diabetics had morphologica1 changes of the abdominal aorta. There was no significative statistic relation in this ana1ysis (p=O.7268). Considering hypertense patients, 12 (9.4%) out of52 individuais had the aortic disease, whilst only 4 (7.5%) out of 128 non-hypertense patients had the disease (p=O.3549). From the 97 tobacco users, 15 (15.5) had the disease, compared with on1y 1 (1.2%) out of83 non-smokers (p=O.0128). On the 26 patients who had a peripheric arterial obstruction, 8 (30.8%) had the event, compared with 8 out of 154 (5.2 %) without a leg obstructive arterial disease (p=O.0015). Applying the multivaried logistic regression model the prevalence of aortic dilatation was studied under several points of view, determining the probability of the event on each selected model The risk for an individual who already has a coronary lesion to present an aneurism or ectasy was of 0.4% on the evaluated group. For those who had 2 or 3 lesions the risk was of 1.7% and 4.5% for those with more than 3 lesions. When associated to smoking, those va1ues increased respectively to 6.90,10, 11.8% and 27.1 %. No hypertension nor tobacco user individuals had presented a risk of 0.3% to have aortic dilatation. Hypertensive patients had 0.7% and smokers 2.3%. When both 1àctors were associated, the risk raised to 4.6%. Association of more than three coronarian lesions leads the risk 8.7% and the presence of an arterial obstruction of the inferior members increases the risk to 12.3%. The largest risk found was in the association of peripheric arterial obstruction and smoking, achieving 30.4%. The Present study allows the conclusion that the prevalence of abdomÜ1al aortic dilatation was of 8.9% (16 out of 180 patients) on this specific sample. The risk was detected more frequently on males, smokers, hypertense, having an obstructive disease on the legs and a diffuse coronary lesion
Mestrado
Cirurgia
Mestre em Cirurgia
30
Rubira, Cláudio José [UNESP]. "Colocação de endoprótese vascular versus cirurgia para coarctação de aorta: revisão sistemática". Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/101620.
Testo completoAbstract (sommario):
Made available in DSpace on 2014-06-11T19:31:32Z (GMT). No. of bitstreams: 0
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rubira_cj_dr_botfm.pdf: 240856 bytes, checksum: 5f30f1a1d2ce6492fd56a190c587cfc5 (MD5)Universidade Estadual Paulista (UNESP)
A Coarctação da aorta (CoA) é responsável por 5% a 7% das cardiopatias congênitas, com uma incidência de 0,3 a 0,4 por 1000 nascidos vivos. A cirurgia foi a única forma de terapia para CoA até 1982, quando a angioplastia tornou-se uma alternativa disponível para o seu tratamento. Recoarctação, aneurisma e dissecção da aorta permaneceram desvantagens de ambos os tratamentos. Para evitar estes inconvenientes, em 1990, endopróteses vasculares foram introduzidas para coarctação nativa e recoarctação e desde então, tornaramse uma abordagem alternativa. A melhor abordagem para o tratamento da CoA, se cirurgia aberta ou a colocação de endoprótese vascular, não está estabelecida. Analisar a efetividade e a segurança da colocação de endoprótese vascular em comparação com a cirurgia aberta em pacientes com CoA. O Grupo Peripheral Vascular Diseases da Cochrane realizou a busca em seu Registro Especializado (última busca Setembro de 2011) e na Central (2011, nº 3). Nós também procuramos em MEDLINE, EMBASE, CINAHL, AMED, Web of Science e LILACS (última busca em setembro de 2011). Foram avaliadas as referências encontradas e aplicados os critérios de inclusão para os estudos selecionados. Não houve restrição de linguagem. Ensaios clínicos controlados aleatorizados ou quase-aleatorizados que compararam pacientes com CoA submetidos a cirurgia aberta ou a colocação de endoprótese vascular. Os autores da revisão avaliaram independentemente os estudos identificados para a elegibilidade de inclusão. Nós excluímos estudos após reunião de consenso. Os critérios de seleção foram aplicados para avaliação do título e resumo de todos os estudos identificados. No total, foram selecionados cinco estudos para a análise de texto completo. Após avaliação detalhada, foram excluídos todos os estudos porque não havia...
Coarctation of the aorta (CoA) accounts for 5% to 7% of congenital heart disease, with an incidence of 0.3 to 0.4 per 1000 live births. Surgery was the only choice of therapy for CoA until 1982 when balloon angioplasty became an available alternative for its treatment. Re-coarctation, aneurysm and aortic dissection remain the disadvantages of both treatments. To avoid those disadvantages, in 1990 endovascular stents were introduced for native coarctation and re-coarctation and since then they have become an alternative approach to surgical repair. The best approach to treat the CoA, whether open surgery or by stent placement, is not clear. To analyze the effectiveness and safety of stent placement compared with open surgery in patients with coarctation of the thoracic aorta. The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (last searched September 2011) and CENTRAL (2011, Issue 3).We also searched MEDLINE, EMBASE, CINAHL, AMED, Web of Science and LILACS (last searched in September 2011). We evaluated the located references and applied the inclusion criteria to selected studies. There was no restriction on language. Randomized or quasi-randomized controlled clinical trials that compared patients with CoA undergoing open surgery or stent placement. The review authors independently assessed the studies identified for eligibility for inclusion. We excluded studies after a consensus meeting. All identified studies were screened and had the selection criteria applied to the title and abstract. In total, we selected five studies for full-text analysis. After detailed evaluation, we excluded all studies because there was no comparison between stent placement and open surgery. There is insufficient evidence with regards to the best treatment for coarctation of the thoracic aorta. This review... (Complete abstract click electronic access below)
31
Rubira, Cláudio José. "Colocação de endoprótese vascular versus cirurgia para coarctação de aorta : revisão sistemática". Botucatu, 2012. http://hdl.handle.net/11449/101620.
Testo completoAbstract (sommario):
Orientador: Paulo Eduardo de Oliveira CarvalhoCoorientador: Antônio José Maria Catâneo
Banca: Luiz Eduardo Villaça Leão
Banca: Marcos Augusto Moraes Silva
Banca: Olavo Ribeiro Rodrigues
Banca: Rúbio Bombonato
Resumo: A Coarctação da aorta (CoA) é responsável por 5% a 7% das cardiopatias congênitas, com uma incidência de 0,3 a 0,4 por 1000 nascidos vivos. A cirurgia foi a única forma de terapia para CoA até 1982, quando a angioplastia tornou-se uma alternativa disponível para o seu tratamento. Recoarctação, aneurisma e dissecção da aorta permaneceram desvantagens de ambos os tratamentos. Para evitar estes inconvenientes, em 1990, endopróteses vasculares foram introduzidas para coarctação nativa e recoarctação e desde então, tornaramse uma abordagem alternativa. A melhor abordagem para o tratamento da CoA, se cirurgia aberta ou a colocação de endoprótese vascular, não está estabelecida. Analisar a efetividade e a segurança da colocação de endoprótese vascular em comparação com a cirurgia aberta em pacientes com CoA. O Grupo Peripheral Vascular Diseases da Cochrane realizou a busca em seu Registro Especializado (última busca Setembro de 2011) e na Central (2011, nº 3). Nós também procuramos em MEDLINE, EMBASE, CINAHL, AMED, Web of Science e LILACS (última busca em setembro de 2011). Foram avaliadas as referências encontradas e aplicados os critérios de inclusão para os estudos selecionados. Não houve restrição de linguagem. Ensaios clínicos controlados aleatorizados ou quase-aleatorizados que compararam pacientes com CoA submetidos a cirurgia aberta ou a colocação de endoprótese vascular. Os autores da revisão avaliaram independentemente os estudos identificados para a elegibilidade de inclusão. Nós excluímos estudos após reunião de consenso. Os critérios de seleção foram aplicados para avaliação do título e resumo de todos os estudos identificados. No total, foram selecionados cinco estudos para a análise de texto completo. Após avaliação detalhada, foram excluídos todos os estudos porque não havia... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Coarctation of the aorta (CoA) accounts for 5% to 7% of congenital heart disease, with an incidence of 0.3 to 0.4 per 1000 live births. Surgery was the only choice of therapy for CoA until 1982 when balloon angioplasty became an available alternative for its treatment. Re-coarctation, aneurysm and aortic dissection remain the disadvantages of both treatments. To avoid those disadvantages, in 1990 endovascular stents were introduced for native coarctation and re-coarctation and since then they have become an alternative approach to surgical repair. The best approach to treat the CoA, whether open surgery or by stent placement, is not clear. To analyze the effectiveness and safety of stent placement compared with open surgery in patients with coarctation of the thoracic aorta. The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (last searched September 2011) and CENTRAL (2011, Issue 3).We also searched MEDLINE, EMBASE, CINAHL, AMED, Web of Science and LILACS (last searched in September 2011). We evaluated the located references and applied the inclusion criteria to selected studies. There was no restriction on language. Randomized or quasi-randomized controlled clinical trials that compared patients with CoA undergoing open surgery or stent placement. The review authors independently assessed the studies identified for eligibility for inclusion. We excluded studies after a consensus meeting. All identified studies were screened and had the selection criteria applied to the title and abstract. In total, we selected five studies for full-text analysis. After detailed evaluation, we excluded all studies because there was no comparison between stent placement and open surgery. There is insufficient evidence with regards to the best treatment for coarctation of the thoracic aorta. This review... (Complete abstract click electronic access below)
Doutor
32
Gentille, Lorente Delicia Inés. "Evaluación de la aorta infrarenal y cribado del aneurisma de aorta abdominal mediante la ecocardiografía transtorácica en pacientes visitados en cardiología". Doctoral thesis, Universitat Rovira i Virgili, 2011. http://hdl.handle.net/10803/69364.
Testo completoAbstract (sommario):
La creciente incidencia del aneurisma de aorta abdominal (AAA) y su mortalidad del
85-90%, en caso de rotura, justifican el realizar un diagnóstico y tratamiento reparador
precoces. Este estudio incluyó a 687 pacientes consecutivos estudiados mediante
ecocardiografía transtorácica (ETT), por cualquier causa, en el servicio de cardiología.
Se detectó un AAA en 28 pacientes (4,2%), siendo sus factores de riesgo el ser fumador
o ex fumador, la edad, el presentar un soplo femoral y las mayores dimensiones de la
aorta suprarenal y del cayado. Conclusiones: el completar la ETT convencional con el
estudio de la aorta infrarenal es factible y útil para realizar cribado del AAA en los
pacientes visitados en cardiología. El cribado debería realizarse principalmente en
pacientes con factores de riesgo para desarrollar un AAA (especialmente si son ³ 55
años) y en aquellos con una alta puntuación en los índices de riesgo del AAA
calculados.The increasing incidence of abdominal aortic aneurysm (AAA) and its mortality of 85- 90% in the event of rupture justify opting for early diagnosis and elective treatment to repair it. So, this study included 687 patients consecutively assessed by transthoracic echocardiography (TTE) for any reason in a cardiology department. An AAA was detected in 28 patients (4,2%), and the risk factors associated were to current and former smoking, age, presence of femoral murmur and a largest suprarenal aorta and aortic arch dimensions . Conclusions: It is feasible and useful to complement conventional TTE with the study of the infrarenal aorta for AAA screening in patients visited at the department of cardiology. This study should be performed mainly in patients with risk factors to develop an AAA (specially if they are ³ 55 years old) and in patients with a high punctuation in the calculated risk scores of AAA
33
Gurgel, Sanderland José Tavares [UNESP]. "Recuperação acelerada após reparo cirúrgico aberto eletivo do aneurisma da aorta abdominal: revisão sistemática da literatura". Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/106002.
Testo completoAbstract (sommario):
Made available in DSpace on 2014-06-11T19:35:12Z (GMT). No. of bitstreams: 0
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000740488.pdf: 1738682 bytes, checksum: 833b5e62b7c76ae97194eca5a3b73543 (MD5)O reparo cirúrgico aberto do aneurisma da aorta abdominal (AAA) é um procedimento com alta taxa de morbimortalidade, internação hospitalar prolongada e custo elevado. Neste cenário, os programas multimodais de aceleração da recuperação pós-operatória (PMARP) podem contribuir para a otimização dos cuidados ao paciente e diminuir a utilização de recursos financeiros, mantendo-se a qualidade e a segurança. O objetivo desta revisão sistemática foi avaliar a eficácia e a segurança destes programas no reparo cirúrgico eletivo do AAA. Realizou-se revisão sistemática de estudos clínicos envolvendo os PMARP no reparo cirúrgico do AAA, avaliando a eficácia e segurança, quando comparados com os cuidados perioperatórios convencionais. Estudos clínicos foram recuperados eletronicamente das bases de dados MEDLINE, EMBASE, LILACS, Cochrane Trials Register (CENTRAL), por meio de estratégia de busca com termos apropriados. Identificaram-se os estudos aleatorizados controlados e os não aleatorizados (série de casos). Formulários padronizados foram utlizados para extração de dados. A análise estatística dos estudos aleatorizados foi executada com o programa REVMAN 5.0.2 e para os estudos não aleatórios foi utilizado o StatsDirect. Foram recuperados 13 estudos de série de casos e um ensaio clínico aleatorizado controlado unicêntrico. No ensaio clínico aleatorizado e controlado verificou-se redução significativa no tempo de hospitalização com o PMARP. A metanálise proporcional de série de casos não resultou em nenhuma diferença significativa entre pacientes tratados pelo PMARP e o tratamento convencional. O PMARP em cirurgias eletivas de AAA reduz o tempo de internação hospitalar, sem aumento de mortalidade. Devido aos níveis baixos de evidências, existe a necessidade de realização de mais ensaios aleatórios controlados para gerar grau de recomendação mais sólido
The open surgical repair of abdominal aortic aneurysm (AAA) is a procedure with high morbidity and mortality rates, prolonged hospital stay and high cost. In this scenario, the multimodal program for accelerated postoperative recovery (MPAPR) can contribute to the optimization of patient care and reduce the use of financial resources, maintaining quality and safety. The aim of this systematic review was to evaluate the efficacy and safety of these programs in elective surgical repair of AAA. We conducted a systematic review of clinical studies involving MPAPR in the surgical repair of AAA, evaluating the efficacy and safety compared with conventional perioperative care. Clinical studies were retrieved electronically from MEDLINE, EMBASE, LILACS, Cochrane Trials Register (CENTRAL), through search strategy with the appropriate terms. Identified the randomized controlled trials and non-randomized (number of cases). Standardized forms were utilized for data extraction. Statistical analysis of randomized trials were performed with the program RevMan 5.0.2 and the non-randomized studies was used StatsDirect. Retrieved 13 studies were case series and a randomized controlled single-center. In randomized controlled clinical trial found a significant reduction in hospitalization time with MPAPR. The meta-proportional number of cases resulted in no significant difference between patients treated by MPAPR and conventional treatment. The MPAPR in elective AAA reduces length of hospital stay without increasing mortality. Due to the low levels of evidence, there is a need for more randomized controlled trials to generate any degree of recommendation
34
Gurgel, Sanderland José Tavares. "Recuperação acelerada após reparo cirúrgico aberto eletivo do aneurisma da aorta abdominal : revisão sistemática da literatura /". Botucatu, 2013. http://hdl.handle.net/11449/106002.
Testo completoAbstract (sommario):
Orientador: Paulo do Nascimento JuniorCoorientador: Regina Paolicci El Dib
Banca: Yara Marconde Machado Castilia
Banca: Marcone Lima Sobreira
Banca: Luiz Marcelo Sá Malbouisson
Banca: Luís Vicente Garcia
Resumo: O reparo cirúrgico aberto do aneurisma da aorta abdominal (AAA) é um procedimento com alta taxa de morbimortalidade, internação hospitalar prolongada e custo elevado. Neste cenário, os programas multimodais de aceleração da recuperação pós-operatória (PMARP) podem contribuir para a otimização dos cuidados ao paciente e diminuir a utilização de recursos financeiros, mantendo-se a qualidade e a segurança. O objetivo desta revisão sistemática foi avaliar a eficácia e a segurança destes programas no reparo cirúrgico eletivo do AAA. Realizou-se revisão sistemática de estudos clínicos envolvendo os PMARP no reparo cirúrgico do AAA, avaliando a eficácia e segurança, quando comparados com os cuidados perioperatórios convencionais. Estudos clínicos foram recuperados eletronicamente das bases de dados MEDLINE, EMBASE, LILACS, Cochrane Trials Register (CENTRAL), por meio de estratégia de busca com termos apropriados. Identificaram-se os estudos aleatorizados controlados e os não aleatorizados (série de casos). Formulários padronizados foram utilizados para extração de dados. A análise estatística dos estudos aleatorizados foi executada com o programa REVMAN 5.0.2 e para os estudos não aleatórios foi utilizado o StatsDirect. Foram recuperados 13 estudos de série de casos e um ensaio clínico aleatorizado controlado unicêntrico. No ensaio clínico aleatorizado e controlado verificou-se redução significativa no tempo de hospitalização com o PMARP. A metanálise proporcional de série de casos não resultou em nenhuma diferença significativa entre pacientes tratados pelo PMARP e o tratamento convencional. O PMARP em cirurgias eletivas de AAA reduz o tempo de internação hospitalar, sem aumento de mortalidade. Devido aos níveis baixos de evidências, existe a necessidade de realização de mais ensaios aleatórios controlados para gerar grau de recomendação mais sólido
Abstract: The open surgical repair of abdominal aortic aneurysm (AAA) is a procedure with high morbidity and mortality rates, prolonged hospital stay and high cost. In this scenario, the multimodal program for accelerated postoperative recovery (MPAPR) can contribute to the optimization of patient care and reduce the use of financial resources, maintaining quality and safety. The aim of this systematic review was to evaluate the efficacy and safety of these programs in elective surgical repair of AAA. We conducted a systematic review of clinical studies involving MPAPR in the surgical repair of AAA, evaluating the efficacy and safety compared with conventional perioperative care. Clinical studies were retrieved electronically from MEDLINE, EMBASE, LILACS, Cochrane Trials Register (CENTRAL), through search strategy with the appropriate terms. Identified the randomized controlled trials and non-randomized (number of cases). Standardized forms were utilized for data extraction. Statistical analysis of randomized trials were performed with the program RevMan 5.0.2 and the non-randomized studies was used StatsDirect. Retrieved 13 studies were case series and a randomized controlled single-center. In randomized controlled clinical trial found a significant reduction in hospitalization time with MPAPR. The meta-proportional number of cases resulted in no significant difference between patients treated by MPAPR and conventional treatment. The MPAPR in elective AAA reduces length of hospital stay without increasing mortality. Due to the low levels of evidence, there is a need for more randomized controlled trials to generate any degree of recommendation
Doutor
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Ninomiya, Otavio Henrique. "Biomecânica da aorta torácica e abdominal: estudo em cadáveres". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5132/tde-09062015-143133/.
Testo completoAbstract (sommario):
INTRODUÇÃO: O tratamento endovascular das doenças da aorta é modalidade consagrada atualmente, sendo realizado em indivíduos jovens e idosos, tanto na aorta torácica quanto na abdominal. Esta terapia baseia-se numa interação adequada entre a endoprótese e a parede aórtica. Neste sentido, o conhecimento do comportamento biomecânico da aorta é fundamental. A aorta humana é uma estrutura complexa, com comportamento biomecânico diferente de acordo com a idade, a região e a presença de doenças. Estudos com biomecânica da aorta humana não aneurismática são escassos. OBJETIVOS: Analisar os parâmetros biomecânicos de falência e as características histológicas da aorta torácica e abdominal humana, correlacionando-os com idade e gênero. MÉTODO: Testes destrutivos uniaxiais de espécimes removidos de 26 aortas frescas de cadáveres foram realizados num aparelho de tração universal. Os parâmetros biomecânicos de falência avaliados foram: força, tensão, estresse, deformação e energia de deformação. Foi realizado estudo histológico do tecido aórtico para quantificação de fibras colágenas, musculares e elásticas. RESULTADOS: Foram analisados os testes biomecânicos válidos de 153 espécimes, sendo 95 da aorta torácica e 58 da aorta abdominal. Na comparação entre aorta torácica e abdominal, realizada por análise de variância, foi observado que diâmetro (30,45 versus 23,99 mm; p < 0,001), espessura (1,69 versus 1,44 mm; p < 0,001), força máxima (6,18 versus 4,85 N; p = 0,001), tensão de falência (19,88 versus 14,53 N/cm; p = 0,001), deformação de falência (0,66 versus 0,49; p = 0,003) e a percentagem de fibras elásticas (19,39 versus 14,06 %; p = 0,011) foram maiores, com significância, na aorta torácica. As correlações de Spearman entre idade e força máxima, estresse de falência, tensão de falência, deformação de falência e energia de deformação foram negativas e significativas na aorta torácica e abdominal. As aortas do sexo masculino, através do teste t de Student, apresentaram maior força máxima e tensão de falência. Não houve diferença na composição histológica entre os gêneros. CONCLUSÕES: A aorta torácica é mais resistente e elástica que a aorta abdominal. O conteúdo de fibras elásticas é maior na aorta torácica. Os idosos apresentam aortas menos resistentes e mais rígidas que os jovens. A aorta do sexo masculino é mais resistenteINTRODUCTION: The endovascular repair of aortic diseases is currently widely performed among young and elderly patients, in both the thoracic and abdominal aorta. This treatment is based on an appropriate interaction between the stent graft and the aortic wall. Thus, it is essential to understand the biomechanical behavior of the aorta. The human aorta is a complex vessel with different biomechanical behaviors according to age, location and diseases. There are few biomechanical studies of the human nonaneurysmal aorta. OBJECTIVES: To analyze the biomechanical properties and histological composition of the human aorta according to age and gender. METHODS: Twenty-six human aortas were harvested whole from fresh cadavers during their autopsies. Each aorta was cut into strips for mechanical testing. Uniaxial tensile tests were performed on a tensile-testing machine. The failure load, failure stress, failure tension, failure strain and strain energy were calculated. A histological study was performed to measure the amount of collagen, elastin and smooth muscle cells in the aortic wall. RESULTS: A total of 153 strips were studied (95 from the thoracic aorta and 58 from the abdominal aorta). The diameter (30.45 versus 23.99 mm; p < 0.001), thickness (1.69 versus 1.44 mm; p < 0.001), failure load (6.18 versus 4.85 N; p = 0.001), failure tension (19.88 versus 14.53 N/cm; p = 0.001), failure strain (0.66 versus 0.49; p = 0.003) and elastin amount (19.39 versus 14.06 %; p = 0.011) were all significantly higher for the thoracic aorta than for the abdominal aorta. There was a significant negative Spearman\'s correlation between age and failure load, failure stress, failure tension, failure strain and strain energy. Male aortas had a higher failure load and failure tension than female aortas. No difference in the histological composition was found between the genders. CONCLUSIONS: The thoracic aorta has a higher strength and elasticity than the abdominal aorta. The elastin amount is higher in the thoracic aorta than in the abdominal aorta. The elderly have weaker and stiffer aortas than the young. Male aortas have a higher strength than female aortas
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Victorio, Jamaira Aparecida 1987. "Efeitos vasculares da hiperativação beta-adrenérgica associados à ativação do sistema-renina-angiotensina-aldosterona". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313897.
Testo completoAbstract (sommario):
Orientador: Ana Paula Couto DavelDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-24T14:07:47Z (GMT). No. of bitstreams: 1 Victorio_JamairaAparecida_M.pdf: 1155350 bytes, checksum: eab5bb2760f0d9abd7c5e93ac2b95b51 (MD5) Previous issue date: 2014
Resumo: A hiperativação dos receptores ß-adrenérgicos (ß-AR) tem importante papel na patogênese de doenças cardiovasculares que cursam com hiperatividade simpática. Dentre os seus efeitos, sugere-se a indução da síntese e liberação de angiotensina II e de aldosterona sistemicamente. A hiperativação dos receptores ß-AR pode ser mimetizada pelo tratamento crônico com isoproterenol (ISO). Já foi demonstrado que o antagonismo do receptor AT1 de angiotensina II ou do receptor de mineralocorticoides (MR) previne parcialmente o remodelamento cardíaco induzido pelo ISO. Entretanto, ainda não está elucidado o envolvimento da angiotensina II e da aldosterona nos efeitos vasculares causados pela hiperativação dos receptores ß-AR. Assim, o objetivo do presente estudo foi investigar as vias de sinalização dos receptores AT1 e MR nas alterações vasculares causadas pelo tratamento por 7 dias com ISO em aorta de ratos, assim como os mecanismos envolvidos. Ratos Wistar (3 meses) foram tratados com ISO (0,3 mg/kg/dia, s.c.) ou veículo (CT) e co-tratados ou não com o antagonista do receptor AT1 losartan (LOS; 40 mg/kg/dia) ou com o antagonista do receptor MR espironolactona (ESP; 200 mg/kg/dia). O tratamento com ISO causou hipertrofia ventricular sem alterações hemodinâmicas, e o co-tratamento com LOS ou ESP atenuaram o remodelamento ventricular observado. Na aorta do grupo ISO observou-se um aumento da resposta máxima à fenilefrina associado à redução da biodisponibilidade de óxido nítrico (NO) e aumento de ânion superóxido, os quais foram prevenidos pelo co-tratamento com ESP, mas não com LOS. O efeito preventivo da ESP sobre a reatividade vascular da aorta dos ratos ISO foi acompanhado de aumento da expressão proteica da HSP90, a qual foi reduzida no grupo ISO. Além disso, a ESP preveniu o aumento da expressão proteica de ß-arrestina, Gai, p-Src, ERK1/2, p- ERK1/2 e gênica de osteopontina na aorta deste grupo. As concentrações plasmáticas de corticosterona ou aldosterona não foram alteradas entre os grupos avaliados. Em conjunto, os dados sugerem que o antagonismo do receptor MR com o uso de espironolactona previne o aumento da resposta contrátil à fenilefrina observada em aorta de ratos tratados com ISO, associado a: aumento da biodisponibilidade de NO e redução do estresse oxidativo; aumento da expressão de HSP90, a qual estabiliza a forma dimérica da eNOS; e prevenção do aumento da expressão proteica de ß- arrestina, Gai1,2, p-Src, ERK1/2 e p-ERK1/2 e gênica de osteopontina, vias de sinalização de estresse oxidativo e prejuízo da função endotelial
Abstract: ß-adrenergic (ß¿AR) receptors overstimulation plays an important role in the pathogenesis of cardiovascular diseases concurrent with sympathetic overactivity. It has been suggested to increase plasma levels of angiotensin II and aldosterone. In line with this, angiotensin II/AT1 receptor or mineralocoticoid (MR) receptor antagonism partially prevents the cardiac remodeling induced by ß-AR overstimulation mediated by isoproterenol (ISO) administration. However the implication of angiotensin II or aldosterone on vascular effects provoked by ß¿AR overstimulation is not yet elucidated. So, the aim of the present study was to investigate the AT1 and MR receptor signaling pathway on vascular alterations caused by 7-day ISO treatment on rat aorta, as well as the mechanisms involved. For this, male Wistar rats (3-month-old) were treated with ISO (0.3 mg/kg/day, s.c.) or vehicle (CT) and co-treated or not with AT1 antagonist losartan (LOS; 40 mg/kg/day, v.o.) or MR receptor antagonist spironolactone (ESP; 200 mg/kg/day, v.o.). The ISO treatment resulted in ventricular hypertrophy without hemodynamic alterations, and LOS or ESP co-treatment attenuated the ventricular remodeling of ISO group. ISO aorta showed an increased phenylephrine maximum response associated with a decreased nitric oxide (NO) bioavailability and an increased in superoxide anion; both effects were prevented by ESP co-treatment, but not by LOS. Beneficial effects of ESP on vascular reactivity of aorta from ISO-treated rats were accompanied by an increased HSP90 protein expression, which was reduced in ISO group. Moreover, ESP prevented the increased protein expression of ß-arrestin, Gai, p- Src, ERK1/2 and p-ERK1/2 and osteopontina gene expression in the aorta from ISO group. Plasma corticosterone and aldosterone were not changed between the groups. In conclusion, our results suggest that spironolactone, an MR receptor antagonist prevented the increased phenylephrine contractile response in aorta from ISO-treated rats, associated with increased NO bioavailability and decreased oxidative stress; increased expression of HSP90 and; prevented the increase of ß-arrestin, Gai1,2, p-Src, ERK1/2 and p-ERK1/2 and osteopontin induced by ß-adrenergic overstimulation. These results suggest that the vascular effects induced by ISO in aorta are mediated by a MR activation
Mestrado
Fisiologia
Mestra em Biologia Funcional e Molecular
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Monteiro, Priscilla de Souza. "O efeito do hipotiroidismo experimental sobre os componentes da matriz extracelular de aortas torácicas de ratos". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/42/42131/tde-29012013-081814/.
Testo completoAbstract (sommario):
O objetivo deste estudo foi investigar os efeitos do hipotiroidismo experimental sobre o leito vascular da aorta torácica. Para a análise histológica foram realizadas colorações de hematoxilina-eosina, picrosirius e Weigert. Na análise de expressão proteica, foram realizadas as quantificações para colágeno I e III, elastina, MMP-9 e MMP-2, TIMP-1 e TIMP-2. As análises histológicas demonstraram uma diminuição da AST das aortas dos animais hipo e juntamente a esta alteração, foi constatada a diminuição da expressão proteica de colágeno do tipo I. Em relação à elastina, foi possível observar aumento da expressão deste elemento nas aortas dos animais hipotiroideos. Na avaliação da expressão proteica para MMP-9, foi possível verificar uma redução desta proteína no grupo hipotiroideo, assim como um aumento da expressão de TIMP-2. Frente aos presentes resultados, é possível sugerir que o estado hipometabólico desencadeado pelo hipotiroidismo afeta as CMLVs comprometendo mecanismos de síntese/degradação, alterando o importante arranjo da MEC presente na aorta torácica.The aim of this study was to investigate hypothyroidism effects on thoracic aorta wall. For histological analyses were performed stains like hematoxilin-eosin, picrosirius and Weigert. In the protein expression assays were performed quantification for collagen I and III, elastin, MMP-9, MMP-2, TIMP-1 and TIMP-2. The histological analyses showed a decrease in aortas CSA and also a decrease in protein expression of collagen I in the hypo group. As regards to elastin, was possible to see an increase of this protein expression in hypo animals. In the evaluation for MMP-9 expression, was found a decrease in this protein and for TIMP-2 an increase in hypothyroidism group. Facing to these results, is possible to suggest that the hypometabolic state triggered by hypothyroidism, affects the VSMCs compromising mechanisms of synthesis/degradation and changing the important constitution of thoracic aorta ECM.
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Teixeira, Jessica de Andrade Moraes. "Efeitos da atividade física de baixa intensidade na estrutura das túnicas íntima e média da aorta em ratos espontaneamente hipertensos (SHR)". Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7944.
Testo completoAbstract (sommario):
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorO exercício contínuo de baixa intensidade é capaz de atenuar a hipertrofia da célula muscular lisa da parede da aorta de ratos espontaneamente hipertensos (SHR), e parece atuar sobre a distribuição de fibras oxitalânicas, elaunínicas e elásticas. As alterações funcionais das grandes artérias relacionadas com a idade, deposição de colágeno e elastina na parede arterial e a elasticidade, são também melhoradas com a atividade física. No presente trabalho objetivamos estudar os efeitos da atividade física aeróbica de baixa intensidade no remodelamento estrutural da artéria aorta em modelo de hipertensão genética de ratos SHR. Através da análise da distribuição das fibras oxitalânicas, elaunínicas e elásticas na aorta dos animais controles e SHR submetidos ou não a atividade física de baixa intensidade. Foram utilizados 32 ratos, sendo 16 ratos SHR machos e 16 ratos normotensos Wistar Kyoto (WKY) machos com 8 semanas de idade. Ratos machos foram alocados em 4 grupos: WKY sedentário (WKY-SED), WKY exercitado (EX-WKY), SHR sedentário (SED-SHR), e SHR exercitado (EX-SHR). Os ratos sedentários foram limitados à atividade na caixa, enquanto que os ratos exercitados foram submetidos a um exercício de 1 h / dia, 5 dias / semana. Esses grupos passaram pelo protocolo de atividade física de 20 semanas e a pressão arterial foi mensurada semanalmente (PA). As aortas foram colhidas e processadas para microscopia de luz, microscopia eletrônica e western blotting. Foram realizadas as colorações orcinol neo-fucsina e resorcina-fucsina de Weigert. No grupo hipertenso, o exercício mantém a PA em um nível relativamente semelhante ao inicio do protocolo, mostrando a capacidade de prevenir o aumento da PA ao longo das 20 semanas. No grupo dos animais hipertensos não tratados, a PA aumenta. A PA aumentou progressivamente nos ratos SED-SHRs atingindo 1894 mmHg, mas o exercício físico impediu este processo. Ao final do experimento a PA nos ratos EX-SHRs foi similar o dos ratos WKY (1184 vs. 1144 mmHg), respectivamente. Observou-se maior expressão de elastina e maior distribuição de fibras oxitalânicas, elaunínicas e elásticas em animais que foram submetidos ao protocolo de exercício físico. A porcentagem de fibras elásticas e oxitalânicas foi menor em SED-SHR comparado com SED-WKY, mas o exercício físico aumentou a porcentagem dessas fibras em ambos os grupos. Através da imuno-histoquímica ultra-estrutural para elastina e fibrilina, os grupos EX-WKY e EX-SHR apresentaram uma marcação mais intensa para elastina e fibrilina. Animais hipertensos que não sofreram o protocolo de exercício físico apresentam espessura da parede da aorta maior que a dos animais que sofreram o exercício. O número de lamelas elásticas, bem como as fibras oxitalânicas e elaunínicas, é maior no grupo EX-SHR, em relação ao SED-SHR. Os grupos exercitados tiveram maior expressão de eNOS que seus respectivos grupos sedentários, e as células endoteliais apresentaram características morfológicas preservadas. A associação da atividade física com modelos de hipertensão genética mostra que o exercício físico tem efeitos benéficos nessa situação, uma vez que atenua a hipertensão e o remodelamento adverso da parede da aorta.
The continuous exercise of low intensity is able to attenuate the hypertrophy of smooth muscle cells in the wall of the aorta of spontaneously hypertensive rats (SHR), and it seems work on the distribution of fiber oxytalan, elaunínicas and elastic. The functional changes of large arteries associated with age, deposition of collagen and elastin in the arterial wall and elasticity are also improved with physical activity. In the present study investigated the effects of aerobic physical activity of low intensity in the structural remodeling of the aorta in genetic model of hypertension in SHR rats. By analyzing the distribution of fiber oxytalan, elaunínicas and elastic in the aorta of SHR and control animals submitted or not the physical activity of low intensity. We used 32 rats, and 16 rats SHR male rats and 16 normotensive Wistar Kyoto (WKY) males with 8 weeks of age.Male rats were divided into 4 groups: sedentary WKY (WKY-SED), exercised WKY (WKY-EX), sedentary SHR (SHR-SED) and exercised SHR (SHR-EX). The rats were limited to sedentary activity box, while the rats were trained on an exercise to 1 h / day, 5 days / week. They passed by the Protocol of 20 weeks of physical activity and blood pressure was measured weekly (BP). Aortas were harvested and processed for light microscopy, electron microscopy and western blotting. Orcinol neo-fuchsin staining were performed and resorcin-fuchsin of Weigert. In the hypertensive group, the exercise keeps the blood pressure in a relatively similar to the start of the protocol, showing the ability to prevent the increase in PA over the 20 weeks. In the group of untreated hypertensive animals, the PA increases. BP increased progressively in rats SED-SHRs reached 189 4 mmHg, but the exercise prevented this process. At the end of the experiment the PA in rats EX-SHRs was similar to the WKY rats (118 4 vs. 114 4 mmHg), respectively. There was increased expression of elastin and increased distribution of fiber oxytalan, elaunínicas and elastic in animals that were subjected to the protocol of exercise. The percentage of elastic fibers and oxytalan was lower in SHR-SED compared with WKY-SED, but exercise increased the percentage of fibers in both groups. By immuno-histochemical ultrastructural for elastin and fibrillin, both groups EX-EX-SHR and WKY showed a stronger mark for elastin and fibrillin. Hypertensive animals that have not been the protocol of exercise have wall thickness of the aorta higher than that of animals that underwent the exercise. The number of elastic lamellae, and the fibers and oxytalan elaunínicas, is greater in the EX-SHR group, for the SHR-SED. The exercise groups had a higher expression of eNOS to their respective sedentary groups, and the endothelial cells showed morphological features preserved. The association of physical activity with genetic models of hypertension shows that exercise has beneficial effects in this situation, since hypertension and reduces the adverse remodeling of the aortic wall.
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Silva, Katiussia Pinho da. "Adrenoceptores- alfa-1 envolvidos na contração da aorta abdominal em modelo experimental de pré-eclâmpsia em ratas". Botucatu, 2016. http://hdl.handle.net/11449/139513.
Testo completoAbstract (sommario):
Orientador: André Sampaio PupoResumo: A Pré-eclâmpsia (PE) é uma desordem hipertensiva gestacional, cuja fisiopatologia tem sido atribuída a forte resposta inflamatória, disfunção endotelial, agregação plaquetária e aumento da resistência vascular. Estudos com PE relatam inadequado aumento na ação de vários vasoconstritores, incluindo endotelina, adenosina, angiotensina II, e noradrenalina ocasionando aumento da pressão arterial. De fato, o sistema nervoso autonômo simpático através do neurotransmissor noradrenalina regula a pressão arterial mediante a ativação dos adrenoceptores-alfa-1 (ARs-alfa-1). No presente estudo, foi investigado através do uso de agonistas e antagonistas seletivos os subtipos de ARs-alfa1 envolvidos na contração da aorta abdominal de ratas prenhes submetidas à um modelo experimental de PE por redução da pressão de perfusão uterina (RUPP), e esses receptores foram comparados com aqueles envolvidos na contração da artéria de ratas virgens. Os resultados indicam que as contrações da artéria aorta abdominal de ratas virgens em resposta à noradrenalina resultam da ativação de AR-alfa-1A e AR-alfa-1D, mas que na artéria da fêmea há uma maior contribuição de AR-alfa-1A do que na respectiva artéria de machos. Além disso, a prenhez induziu plasticidade nos subtipos de ARs-alfa-1 envolvidos na contração da artéria aorta abdominal, uma vez que houve menor participação de AR-alfa-1A nas contrações de ratas prenhes do que aquela observada na artéria de ratas virgens. Por outro lado, na artéria aorta ab... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Preeclampsia (PE) is a gestational hypertensive disorder, for which the physiopathology has been attributed to an intense inflammatory response, endothelial disfunction, platelet aggregation and increased vascular resistance. Previous studies reported that in PE there is an inadequate increase in the action of several vasoconstrictors, including endothelin, adenosine, angiotensin II and noradrenaline. In fact, the sympathetic nervous system by releasing the neurotransmitter noradrenaline regulates the arterial pressure through activation of 1-adrenoceptors (1-ARs). The present study investigated the 1–ARs subtypes involved in the contractions of the abdominal aortae from pregnant rats submitted to an experimental model of PE, the reduced in uterine perfusion pressure (RUPP), compared these receptors with those involved in the contractions of abdominal aortae from non-pregnant (virgin) and pregnant female rats. The results indicate that there are both 1A–ARs and 1D– ARs in abdominal aortae from non pregnant females, but that the 1A–ARs is more important in the contraction of the female than in the contraction of the respective artery from male rats. Pregnancy induces plasticity in the 1 – ARs of the abdominal aortae, since there was a less significant participation of 1A-AR in the contraction of abdominal aortae from pregnant rats than in the artery of virgin females. In the other hand, selective agonists and antagonists presented complex behaviours in the abdominal ao... (Complete abstract click electronic access below)
Mestre
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Solanich, Valldaura Teresa. "Síndrome compartimental abdominal en aneurismas de aorta abdominal rotos". Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/665385.
Testo completoAbstract (sommario):
Introducción:
Los aneurismas de aorta abdominal rotos (AAAR) presentan una alta tasa de mortalidad, incluso aquellos pacientes que sobreviven a la cirugía (32 al 80%1-4). El fallo de varios órganos en el postoperatorio inmediato supone una causa frecuente de muerte. El síndrome compartimental abdominal (SCA) se presenta en un 30-53%, independientemente de la técnica terapéutica realizada (cirugía abierta o endovascular), pudiendo comportar un fallo multiorgánico, con una mortalidad de más del 70%(3). El SCA es un factor predictor de mortalidad en los AAAR, su prevención, detección y tratamiento mediante laparotomía descompresiva puede aumentar la supervivencia.
El objetivo del presente estudio ha sido determinar la supervivencia a 30 días de los pacientes intervenidos de aneurisma de aorta abdominal rotos, los factores de riesgo del síndrome compartimental abdominal y analizar los resultados del cierre abdominal diferido.
Material y métodos:
Estudio observacional retrospectivo de pacientes intervenidos de AAAR en el servicio de Angiología y Cirugía Vascular del Hospital Universitari Parc Taulí entre 2002 y 2016.
Se consideró AAAR aquellos pacientes con extravasación de sangre o hematoma fuera del AAA en la tomografía computerizada realizada preoperatoriamente, y/o el hallazgo de hematoma fuera del AAA durante la cirugía abierta.
Se diagnosticó de SCA aquellos pacientes que cumplían los parámetros establecidos por la WSACS o aquellos pacientes en que no pudo ser posible el cierre abdominal primario a criterio del cirujano vascular.
Se registraron variables demográficas, tipo de intervención, cierre abdominal diferido, factores de riesgo de SCA pre-intra-postoperatorios y supervivencia a 30 días.
Resultados:
Se incluyeron 61 pacientes de 87 elegibles, 39 cirugía abierta y 22 endovascular.Se excluyeron los pacientes con AAAR no tributarios de intervención. La mortalidad global intra-postoperatoria fue del 54%, siendo del 66,7% para la cirugía abierta y del 31,8% en la cirugía endovascular (p=0,009)
Se pudieron analizar los resultados postoperatorios de 43 pacientes que sobrevivieron a la cirugía, 21 cirugía abierta (48,8%) y 22 endovascular (51,2%). La supervivencia postoperatoría global a 30 días fue del 67,4% ( 61,9% cirugía abierta y 72,7 % endovascular).
Los factores de riesgo del SCA más frecuentes fueron: perfusión de >5 litros, coagulopatía, transfusión > 6 concentrados de hematies y la acidosis metabólica.
En el grupo de cirugía abierta: 12 presentaron SCA y 4 fueron éxitus. 9 no presentaron SCA, siendo éxitus 4. (p=0,604). En el grupo endovascular, 6 casos presentaron SCA, siendo éxitus 4, mientras que de los 16 casos que no presentaron SCA, 3 fueron éxitus (p=0,032)
En el grupo de cirugía abierta: en 9 casos se dejó el abdomen abierto (42,9%) y en 12 se cerró de forma primaria. El cierre abdominal diferido comportó un incremento de la supervivencia (88,9% versus 41,7%). En el grupo endovascular: en 6 casos se procedió a laparotomia descompresiva en el mismo acto quirúrgico, esta laparotomia descompresiva no supuso un incremento de la supervivencia (42,9% versus 87,5%)
Conclusiones:
En nuestra serie en el grupo de cirugía abierta el síndrome compartimental abdominal no incrementó la mortalidad.
El síndrome compartimental abdominal incrementó la mortalidad en el grupo de cirugía endovascular.
La mortalidad intraoperatoria de los aneurismas de aorta abdominal rotos fue mayor en el grupo de cirugía abierta.
No hallamos diferencias significativas en cuanto a la mortalidad postoperatoria de los aneurismas de aorta abdominal rotos según el tipo de cirugía.
Los factores de riesgo de síndrome compartimental abdominal han sido: perfusión >5 litros, coagulopatía en el período postoperatorio inmediato, transfusión >6 concentrados de hematies y acidosis metabólica intraoperatoria o postoperatoria immediata.
La laparotomía descompresiva primaria incrementa la supervivencia en el grupo de ciru-gía abierta no así en el grupo de cirugía endovascular.Introduction: Ruptured abdominal aortic aneurysms (RAAA) carry a high mortality. Patients who survive surgery have mortality rates of 32 to 80%1-4). Multi-organ failure during the immediate postoperative period is a very common cause of death. Abdominal compartment syndrome (ACS) is present in 30-53% of cases and represents a frequent cause of multi-organ failure with both endovascular and open inter-ventions, which accounts for 70% of deaths (3). ACS is an independent predictor of mortality in RAAA and its prevention, detection and treatment with decompressive laparotomy can increase survival. The aim of the present study was to analyse 30-day survival of patients undergoing RAAA repair, the presence of risk factors for ACS and RAAA and the results obtained with delayed abdominal closure. Material and methods: A retrospective observational study was designed, with the inclusion of patients undergoing RAAA repair between 2002 and 2016 in the Angiology and Vascular Surgery service, at the Hospital Uni-versitari Parc Taulí. RAAA was defined as the extravasation of blood or haematoma outside the wall of the abdominal aortic aneurysm (AAA) in computed tomography (CT) angiography and/or evidence of haematoma outside the AAA during the surgery. The presence of ACS was established according to the parameters established by the WSACS or when primary abdominal closure could not be performed at the discretion of the vascular surgeon. Demographic variables, type of surgery, delayed abdominal closure, pre-, intra- and postoperative ACS risk factors and 30-day survival were collected. Results: A total of 61 patients were included out 85 eligible: 39 open and 22 endovascular surgeries.Patient not submitted to repair were excluded. Overall intra- and postoperative mortality was 54% (66.7% with open surgery and 31.8% with endovascular surgery (p=0.009)). The postoperative results of 43 patients who survived surgery were analysed: 21 (48.8%) with open surgery and 22 (51.2%) with endovascular surgery. Overall 30-day postoperative survival was 67.4% (61.9% with open surgery and 72.7 with endovascular surgery). The most frequent risk factors for abdominal compartment syndrome were: perfusion >5 litres, coag-ulopathy, transfusion > 6 units of packed red blood cells and metabolic acidosis. In the open surgery group: 12 presented ACS, 4 of which died, and 4 of the 9 patients who did not present ACS died (p=0.604). In the endovascular surgery group, 6 patients presented ACS, 4 of which died, and 3 of the 6 patients who did not present ACS died (p=0.032). Of the patients who underwent OS, the abdomen was left open in 9 cases (42.86%), and primary abdominal closure was performed in 12. Delayed abdominal closure increased survival (88.9% vs. 41.7%). Six patients in the endovascular group had decompressive laparotomy during the same sur-gical procedure. Decompressive laparotomy did not increase survival in the endovascular surgery group (42.9% vs. 87.5%). Conclusions: Abdominal compartment syndrome did not increase mortality in the open surgery group. Abdominal compartment syndrome increased mortality in the endovascular surgery group. Intraoperative mortality of RAAA was higher in the open surgery group. We did not detect differences in postoperative mortality of RAAA according to the type of surgery. The risk factors for abdominal compartment syndrome were: perfusion >5 litres, coagulopathy, trans-fusion >6 units of packed red blood cells and metabolic acidosis. Primary decompressive laparotomy increased survival in the open surgery group, but not in the endovascular surgery group.
41
Atsma, Meike S. "Aortenwrapping bei dilatierter Aorta ascendens eine Alternative zum Aortenersatz? /". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974322393.
Testo completo
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Martufi, Giampaolo. "Multiscale Modeling of the Normal and Aneurysmatic Abdominal Aorta". Licentiate thesis, KTH, Biomekanik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-28925.
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Wells, Sarah Melissa. "Structural-mechanical relations in the developing ovine thoracic aorta". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0020/NQ45753.pdf.
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44
Choudhury, Nusrat Zabeen. "Characterization of healthy and diseased human ascending aorta tissue". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=83857.
Testo completoAbstract (sommario):
Little information is available on the structure or mechanical properties of the human ascending aorta (AA). Most studies to date have assumed homogeneous tissue mechanical properties. The objective of this study was to investigate the local variation in AA tissue structure and mechanics. Healthy and pathologic tissue samples of human AA were obtained at autopsy and surgical pathology. Each aortic ring was sectioned into quadrants; anterior, posterior, medial (inner curvature) and lateral (outer curvature). Samples from each quadrant were processed for histological analysis and biaxial tensile testing. The results from this study indicate that regional differences are present in both healthy and diseased human AA tissue. Overall, the medial quadrant contained significantly more elastin and mechanically, it was the thickest, least stiff and most likely to fail in comparison to the other quadrants. The assumption of homogeneity in AA tissue properties may not be a valid one.
45
藍志洪 e Chi-hung Nam. "Effect of cerivastatin on endothelial function in rat aorta". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B42575837.
Testo completo
46
Almonacid, Jorge Bruno, e Irma Jaquelina Rodríguez. "Educación a pacientes con aneurisma y disección de aorta". Bachelor's thesis, Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería, 2004. http://bdigital.uncu.edu.ar/7882.
Testo completoAbstract (sommario):
En este trabajo de investigación se intenta saber el grado de interés y preocupación de los pacientes diagnosticados con aneurisma y disección aórtica en cuanto a su patología y su tratamiento. Es por ello que tiene como objetivo general determinar el tipo de educación y cuáles fueron las fuentes de información que recibieron dichos pacientes durante su fase de internación en el servicio de unidad coronaria del Hospital Central durante el año 2003, sobre cuidados y cambios de hábitos para evitar complicaciones y secuelas. Es un estudio cuantitativo y descriptivo, de corte transversal. Se trabajó con una muestra de 18 pacientes internados a los cuales se les realizó una encuesta estructurada con preguntas cerradas.Fil: Almonacid, Jorge Bruno. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..
Fil: Rodríguez, Irma Jaquelina. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Escuela de Enfermería..
47
Argenta, Rodrigo. "Aneurisma de aorta torácica : um modelo experimental em suínos". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/16366.
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48
Fulton, James Oliver. "Penetrating injuries of the thoracic aorta and its branches". Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/26329.
Testo completoAbstract (sommario):
Penetrating injuries of the intrathoracic great vessels are well recognized although uncommon. In the First World War no survivors with thoracic vascular injury were recorded among soldiers treated with penetrating injuries to the chest as recorded by Makins. The first record of successful repair of a penetrating thoracic aortic injury was in 1922 by Dshanelidze in Russia. Similar to Makins' experience, De Bakey and Simeone in the Second World War recorded no surviving patients with involvem_ent of the thoracic aorta and its branches among American soldiers. Furthermore, no injuries to the thoracic aorta and its branches were recorded in Korean war soldiers undergoing vascular surgery by both Jahnke and Hughes. Rich reported 3 survivors of aortic injuries in the Vietnam war among 1000 patients with vascular injuries. By 1969 only 43 successfully treated cases had been reported but increasing numbers of patients sustaining injuries to the great arteries at the level of the thoracic inlet have been reported subsequently in civilian practice. Experience has grown over the years but patient numbers remain small and individual surgeons may only manage 2 or 3 of these patients in his life time. The largest single reported series consists of 93 patients in Memphis over a 13 year period. All victims were rapidly transported to hospital and were resuscitated en route. As a consequence, a large number critically ill patients reached hospital who may have died in earlier years. However some of these patients inevitably died in hospital contributing to the high mortality of 16, 7% reported. Our experience is different in that most of our victims who reach hospital will survive as poor community triage facilities prevent more than 95% of penetrating thoracic vascular trauma victims reaching hospital alive, hence we have a selection of less severely injured patients who eventually reach our hospital alive producing our mortality rate of 5%. Another important difference is that most of our patients suffered stab wounds as compared to gunshot wounds noted in the Memphis. Buchan and Robbs in Durban reported on 52 patients who had penetrating cervicomediastinal vascular injury with a remarkably similar experience to our own in Cape Town with the exception of a larger number of aortic injuries (21 out of 52 patients) recorded and a higher mortality rate of 17% as a result of these aortic injuries.
49
Hemmasizadeh, Ali. "Characterization of Heterogeneous Material Properties of Aorta Using Nanoindentation". Diss., Temple University Libraries, 2013. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/240046.
Testo completoAbstract (sommario):
Mechanical EngineeringPh.D.
Arterial mechanical properties have received increasing attention in the past few decades due to their vast effect on predicting cardiovascular diseases and injuries. The heterogeneity of thoracic aortic tissue was characterized in terms of viscoelastic material properties and correlations were obtained between these properties and tissue morphology. Additionally, the effect of material preservation on the material properties was determined. Changes in the mechanical properties of porcine thoracic aorta wall in the radial direction were characterized using a quasi-linear viscoelastic modeling of nanoindentaiton tests. Two layers of equal thickness were mechanically distinguishable in descending aorta based on the radial variations in the instantaneous Young's modulus E and reduced relaxation function G(t). Overall, comparison of E and Ginf of the outer half (70.27±2.47 kPa and 0.35±0.01) versus the inner half (60.32±1.65 kPa and 0.33±0.01) revealed that the outer half was stiffer and showed less relaxation. The results were used to explain local mechanisms of deformation, force transmission, tear propagation and failure in arteries. A multimodal and multidisciplinary approach was adopted to characterize the transmural morphological properties of aorta. The utilized methods included histology and multi-photon microscopy for describing the wall micro-architecture in the circumferential-radial plane, and Fourier-Transform infrared imaging spectroscopy for determining structural protein, and total protein content. The distributions of these quantified properties across the wall thickness of the porcine descending thoracic aorta were characterized and their relationship with the mechanical properties was determined. It was revealed that there is an increasing trend in mechanical stiffness, Elastic lamella Density (ELD), Structural Protein (SPR), Total Protein (TPR), and Elastin and Collagen Circumferential Percentage (ECP and CCP) from inner layers toward the outer ones. Finally two larger regions with equal thickness (inner and outer halves) were determined based on cluster analysis results of ELD which were in agreement with the cluster analysis of instantaneous Young's modulus. Changes to the local viscoelastic properties of fresh porcine thoracic aorta wall due to three common storage temperatures (+4 oC, -20 oC and -80 oC) within 24 hours, 48 hours, 1 week and 3 weeks were characterized. The changes to both elastic and relaxation behaviors were investigated considering the multilayer, heterogeneous nature of the aortic wall. For +4 oC storage samples, the average instantaneous Young's modulus (E) decreased while their permanent average relaxation amplitude (Ginf) increased and after 48 hours these changes became significant (10%, 13% for E, Ginf respectively). Generally, in freezer storage, E increased and Ginf showed no significant change. In prolonged preservation (> 1 week), the results of +20 oC storage showed significant increase in E (20% after 3 weeks) while this increase for -80 oC was not significant, making it a better choice for tissue cold storage applications. Results from this dissertation present a substantial step toward the anatomical characterization of the aortic wall building blocks and establishing a foundation for understanding the role of microstructural components on the functionality of blood vessels. A better understanding of these relationships would provide novel therapeutic targets and strategies for the prevention of human vascular disease.
Temple University--Theses
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Nam, Chi-hung. "Effect of cerivastatin on endothelial function in rat aorta". Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/hkuto/record/B42575837.
Testo completo