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Ocorrência de bactérias periodontais em ateromas coletados de artéria coronária de pacientes portadores de periodontite crônica / Occurrence of periodontal bacteria in atheroma coronary arteries from patients with chronic periodontitisMarcelino, Silvia Linard 25 August 2008 (has links)
Hoje em dia existe um consenso de que a prevenção e o tratamento de doenças periodontais são importantes na redução de mortalidade e morbidade associadas à doença cardíaca, e uma correlação entre aterosclerose e doença periodontal ainda é desconhecida. Neste estudo, a presença de Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Campylobacter rectus e Enterococcus faecalis em placas de ateroma de artérias coronárias foram detectadas. Trinta pacientes programados para endarterectomia, 28 pacientes com periodontite crônica e 2 sem doença periodontal foram incluídos no estudo. DNA bacteriano foram extraídos dos ateromas e a presença de bactérias periodontais foram detectadas através da reação em cadeia da polimerase. DNA bacteriano periodontal foi encontrado em 28 amostras de ateroma de pacientes periodontais: P. gingivalis em 14 (50%); P. nigrescens em 4 (14,3%), P. intermedia em 3 (10,7%); E. faecalis em 3 (10,7%), T. forsythia em 2 (7,1%); A. actinomycetemcomitans em 2 (7,1%); C. rectus em 2 (7,1%); T. denticola em 1 (3,6%); e P. endodontalis em 1 (3,6%). Fusobacterium nucleatum não foi encontrado em nenhuma das amostras analisadas. Em duas amostras de ateroma de pacientes sem doença periodontal, P. gingivalis e E. faecalis foram observadas em uma amostra e P. intermedia em ambas as amostras. Nossos resultados sugerem que a presença de P. gingivalis em ateroma de artérias coronárias pode apresentar um envolvimento com aterosclerose e parecendo ser um microrganismo da relação aterosclerose e periodontite crônica. / Nowadays there is a consensus that prevention and treatment of periodontal diseases are important in the reduction of mortality and morbidity associated to cardiovascular diseases, and a correlation between atherosclerosis and periodontal disease is still unclear. In this study, the presence of Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Campylobacter rectus and Enterococcus faecalis in atheroma plaques from coronary arteries was determined. Thirty patients scheduled for endarterectomy, 28 patients with chronic periodontitis and 2 without periodontal diseases were included in this study. Bacterial DNA was extracted from atheroma and periodontal bacteria detection was done by polymerase chain reaction. Periodontal bacterial DNA was found in 28 atheroma samples from periodontal patients: P. gingivalis in 14 (50%); P. nigrescens in 4 (14.3%); P. intermedia in 3 (10.7%); E. faecalis in 3 (10.7%), T. forsythia in 2 (7.1%); A. actinomycetemcomitans in 2 (7.1%); C. rectus in 2 (7.1%); T. denticola in 1 (3.6%); and P. endodontalis in 1 (3.6%) samples. Fusobacterium nucleatum was not detected in any atheroma analyzed. In two atheroma samples from patients without periodontal disease, P. gingivalis and E. faecalis were observed in one sample and P. intermedia in both samples. Our results suggest that the presence of P. gingivalis in atheroma from coronary arteries may be involved in atherosclerosis, and it appears to be a relationship microorganism atherosclerosis and chronic periodontitis.
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Efeito do treinamento físico no remodelamento de grandes artérias em ratos normotensos e hipertensos. / Effect of exercise training in the remodeling of large arteries in spontaneously hypertensive and normotensive rats.Jordão, Maria Tereza 11 September 2008 (has links)
Investigamos os efeitos do treinamento físico (T) aeróbio sobre o possível remodelamento de grandes artérias de animais hipertensos (SHR) e normotensos (WKY). Os animais foram submetidos à T em esteira (50-60% da capacidade máxima, 1h/dia, 5dias/semana) ou mantidos sedentários (S) por 3 meses. Ao final dos protocolos, foram submetidos à canulação crônica para registros hemodinâmicos basais. A seguir foram anestesiados e perfundidos com salina e PFA 4% para análise histológica e com solução Karnovski para microscopia eletrônica de transmissão (MET). A aorta torácica e abdominal e as artérias carótida, renal e femoral foram retiradas e processadas para a técnica de Weigert/Hematoxilina e MET. Na análise morfométrica foram determinados os seguintes parâmetros: DI, DE, espessura de parede, razão média/luz e AST de todos os segmentos arteriais, enquanto que na análise estereológica quantificou-se a densidade numérica (QA), a densidade volume (VV) e a densidade de área (SV) do núcleo do músculo liso vascular e do componente elástico (total, lamelar e fibrilar). Nos SHRS (vs WHYS) a PAM e FC basais apresentavam-se elevados (172±1 mmHg e 386±9 bpm, respectivamente). TF foi igualmente eficaz em aumentar o ganho de capacidade física em ambos os grupos (+264±12 e +279±33 m), mas quedas da PAM (-4%) e FC (-7%) foram observadas somente nos SHRT. Não foram observadas diferenças ultra-estruturais marcantes nos vasos de SHR e WKY, porém o T foi eficaz em reorientar as células musculares lisas, reduzir o colágeno da matriz extracelular, prevenir a duplicação da limitante elástica interna, reduzir a vacuolização subendotelial em ambos os grupos e prevenir a fragmentação da lâmina elástica interna na aorta torácica dos SHR. Nos SHRS vs WKYS houve aumentos significativos do calibre da aorta torácica (+7%), carótida (+19%), redução da abdominal (-7%) e aumentos da razão média/luz das artérias renal (+80%) e femoral (+48%). Houve também aumentos significativos de espessura e AST da carótida (+27% e +47% respectivamente), femoral (+64% e +62% respectivamente) e da aorta torácica (+31%). O T não causou alterações geométricas nas grandes artérias de SHR e de WKY, com exceção de aumento inesperado da razão média/luz na femoral (+31%, p<0,05) apenas nos SHRT. Quantos aos parâmetros estereológicos observou-se aumentos significativos na VV (+60%) e SV (+60%) do músculo liso vascular da aorta, acompanhados de redução significativa da VV (-10% e -29%) e SV (-11% e -23%) do componente elástico total e lamelar, sem alteração do componente elástico fibrilar nos SHRS. A razão entre densidade de volume de lamelas e fibrilas, densidade de volume do músculo liso vascular também foi significativamente reduzida (-43% e -56% respectivamente) nos SHRS. Por outro lado, o T determinou redução da QA (-25%), a VV (-40%) e SV (-40%) do músculo liso vascular apenas nos SHRT, sem alterar o componente elástico lamelar e fibrilar. No entanto, a razão componente elástico/músculo liso vascular foi corrigida pelo T (aumentos de +85% e +90%, respectivamente, vs SHRS). Nossos dados sugerem que a hipertensão aumenta preferencialmente a espessura das grandes artérias de forma a manter constante a tensão desenvolvida pela parede vascular, enquanto que o treinamento aeróbio de baixa intensidade, independente do nível de pressão arterial, modifica essencialmente o arranjo ultra-estrutural do vaso, determinando adicionalmente na artéria muscular esquelética alterações geométricas compensatórias a ajustes da microcirculação induzidos pelo exercício. Além disso, a comparação de nossos resultados com aqueles induzidos pelo treinamento na microcirculação muscular esquelética sugerem que os efeitos do T diferem entre grandes e pequenas artérias/arteríolas. / We investigated the effects of exercise training (T) on the possible remodeling of large arteries of spontaneously hypertensive (SHR) and normotensive rats (WKY). The animals were submitted to treadmill T (50-60% of maximum capacity, 1h/day, 5 d/week) or kept sedentary (S) for 3 months. At the end of the protocols, they were submitted to chronic cannulation for records of baselines hemodynamics. Following they were anesthetized and perfused with saline and PFA 4% for histological analysis and Karnovski solution for transmission electron microscopy (TEM). The thoracic and abdominal aorta and carotid, renal and femoral arteries were harvested and processed for the technique of Weigert/Hematoxylin and TEM. In morphometric analysis were determined the following parameters: DI, DE, thickness of wall, media/lumen ratio and AST in all arterial segments, while the stereological analysis quantified the density number (QA), the density volume (VV) and density of area (SV) of the nucleus of vascular smooth muscle and the elastic component (total, lamellar and fibrillar). In SHRS (vs WHYS) MAP and HR baseline were seen to be high (172 ± 1 mmHg and 386 ± 9 bpm respectively). T has also been effective in increasing the gain of physical capacity in both groups (+264 ± 12 and +279 ± 33 m), but falls in MAP (-4%) and HR (-7%) were observed only in SHRT. There were no significant ultrastructural differences in vessels of SHR and WKY, but T was effective in reorganize the smooth muscle cells, reduce the collagen of extracellular matrix, preventing the duplication of internal elastic lamina, reduce the subendothelial vacuolization in both groups and prevent the fragmentation of internal elastic lamina in the thoracic aorta of SHR. In SHRS there were significant increases in the caliber of the thoracic aorta (+7%) carotid (+19%), reduction of abdominal aorta (-7%), increases of the media/lumen ratio of the renal arteries (+80%) and femoral (+48%). There were also significant increases in thickness of the carotid and AST (+27% and +47% respectively), femoral (+64% and +62% respectively) and the thoracic aorta (+31%). T did not cause changes in the geometry of the large arteries of SHR and WKY, except for unexpected increase of media/lumen ratio in the femoral (+31%, p <0.05) only in SHRT. In spite of stereological parameters there were significant increases in VV (+60%) and SV (+60%) of the vascular smooth muscle of the thoracic aorta, with significant reduction of VV (-10%, -29%) and SV (-11 %, -23%) of the total and lamellar elastic component without changing the fibrillar elastic component in SHRS. The ratio between density of volume of lamellas and fibrils and density of volume of vascular smooth muscle was also significantly reduced (-43% and -56% respectively) in SHRS. Furthermore, T determined reduction of QA (-25%), VV (-40%) and SV (-40%) only in vascular smooth muscle in SHRT, without changing the lamellar and fibrillar elastic component. However, the ratio between elastic component and vascular smooth muscle cell was corrected by T (increases of +85% and +90% respectively, vs SHRS). Our data suggest that hypertension increases preferably the thickness of the large arteries in order to maintain constant tension developed by the vascular wall, while the low-intensity aerobic training, regardless of the level of blood pressure, changes essentially the ultrastructural arrangement of vessel, determining further, in skeletal muscle artery, geometric changes compensatory to adjustments of the microcirculation induced by exercise. Moreover, the comparison of our results with those induced by training in skeletal muscle microcirculation suggests that the effects of T differ between large and small arteries/arterioles.
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Lobação e distribuição bronquial e arterial do pulmão da paca (Agouti paca, Linnaeus, 1766) / Lobation, bronchial and arterial distribution in lungs of the paca (Agouti paca, Linnaeus, 1766)Rehder, Axel Mauro de Andrade 01 July 2005 (has links)
Objetivou-se neste estudo descrever a anatomia macroscópica dos pulmões e da árvore brônquica da paca, além de padronizar a vascularização arterial pulmonar, mediante dissecação da árvore brônquica e do tronco pulmonar injetado com neoprene látex corado, de dez pulmões devidamente fixados em solução aquosa de formol à 10%, de pacas adultas, machos e fêmeas, que vieram a óbito, por motivos diversos os quais não afetaram os órgãos em questão e eram provenientes do criadouro de pacas do Setor de Animais Silvestres da do Departamento de Zootecnia da Faculdade de Ciências Agrárias e Veterinárias - Câmpus de Jaboticabal, da Universidade Estadual Paulista - UNESP. Foi observado em 100% dos casos estudados que o pulmão direito da paca está constituído por quatro lobos bem delimitados por fissuras interlobares: cranial; médio, este bilobado em parte cranial e parte caudal; lobo acessório; o pulmão esquerdo possui três lobos bem delimitados: cranial, este bilobado em parte cranial e parte caudal; caudal e um pequeno lobo acessório. O lobo caudal, mais desenvolvido, tem em sua face medial a justaposição do lobo acessório. Também em todos os casos observados, apenas um padrão de distribuição brônquica foi observado.Quanto à vascularização, a artéria pulmonar direita, emite dois ramos distintos para o lobo cranial, além dos ramos independentes para a parte cranial e parte caudal do lobo médio, o ramo do lobo acessório e o ramo do lobo caudal; a artéria pulmonar esquerda emite dois ramos ascendentes e um descendente, respectivamente para as porções cranial e caudal do lobo cranial; o ramo do lobo caudal é irrigado pela própria continuação da artéria pulmonar esquerda que emite de cinco a seis ramos dorsais e de sete a oito ramos ventrais. / The purpose of this study was to describe the anatomy of the lungs and the distribution of the branches of the pulmonary arteries of the pacas by dissection of the bronchial tree and of the lung trunk injected with coloured latex neoprene of ten lungs properly fastened in aqueous solution of formol to the 10%, of adult pacas, males and female. It was observed in 100% of the cases studied that the right lung of the paca is constituted by four lobes, which were de1imnited by well defined inter1obar grooves. Four 1obes were indentified: crania1, medium, caudal and accessory, the 1ast one subdivided into lateral and media1 portions. The 1eft 1ung had on1y two lobes: crania1 and cauda1. The right pu1monary artery sent out the branch of the cranial lobe, which divided itself into ascending and descending branches. The next branch arising from the right pulmonary artery was the branch of the accessory 1obe and divided itself into lateral and media1 branches. The 1ast branch arising form the pu1monary artery was the branch of the cauda1 1obe, which originated seven to 16 arterial branches. The left pulmonary artery sent out the independent ascending and descending branches and in the end continued as the branch of the caudal lobe, which sent out six to 14 arterial branches.
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Associação entre doença cardiovascular e demência: um estudo clinicopatológico / Association between cardiovascular disease and dementia: a clinicopathological studyZoriki, Claudia Kimie Suemoto 05 February 2010 (has links)
INTRODUÇÃO: Recentemente, fatores de risco cardiovascular (FRCV) e doenças cardíacas têm sido associados à demência, doença de Alzheimer (DA) e demência vascular (DV). O objetivo deste trabalho é investigar a associação entre doença cardiovascular comprovada anatomicamente e demência, definida por critérios clínicos, neuropatológicos e clinicopatológicos. MÉTODOS: Trata-se de estudo transversal com material do Banco de Encéfalos Humanos do Grupo de Estudos em Envelhecimento Cerebral. Aterosclerose de artérias carótidas e do polígono de Willis (PW) e hipertrofia miocárdica foram avaliados em material de autópsia e relacionados à prevalência de demência. Dados demográficos e FRCV também foram comparados quanto à presença de demência. Esta foi definida por três critérios: (1) clínico de acordo com escalas cognitivas aplicadas ao informante do falecido; (2) neuropatológico de acordo com critérios aceitos para a classificação de DA e DV; (3) clinicopatológico de acordo com a avaliação cognitiva e com a presença de lesões cerebrais associadas à DA e DV. RESULTADOS: No estudo clínico, foram incluídos 603 indivíduos maiores de 50 anos de idade com avaliação cognitiva e cardiovascular. Demência esteve associada a obstruções críticas (75%) em artérias carótidas, a menor peso cardíaco e a menor espessura da parede ventricular esquerda. Os portadores de demência definida por critérios clínicos eram mais idosos e apresentaram maior proporção de acidente vascular cerebral (AVC) referido pelo informante, sedentarismo, insuficiência cardíaca e menor índice de massa corpórea do que os indivíduos sem demência. No estudo neuropatológico, foram avaliados 183 indivíduos que se dividiram em três grupos: controles (n=124), portadores de DA (n=31) e DV (n=28). Indivíduos com DA apresentaram maior proporção de obstruções75% em artérias carótidas do que controles. Os portadores de DV, além de maior gravidade da aterosclerose carotídea, também apresentaram maior obstrução em artérias do PW do que controles. Quanto aos dados demográficos e FRCV, a idade foi maior em indivíduos com DA e DV em relação a controles e AVC referido foi mais prevalente entre os portadores de DV. No estudo clinicopatológico, foram incluídos 124 controles, 12 portadores de doença cerebral assintomática (DCA) e 47 dementados. Maior gravidade da aterosclerose carotídea e das artérias do PW foi observada em portadores de demência em relação a controles. Quanto aos dados demográficos e FRCV, indivíduos com DCA e demência eram mais idosos do que controles. A escolaridade de portadores de DCA foi maior do que controles e AVC referido foi mais prevalente entre dementados em relação a controles. CONCLUSÕES: Doença cardiovascular, particularmente aterosclerose de artérias carótidas e do PW, estão associados à maior chance de demência. Medidas preventivas que visem retardar a progressão da aterosclerose podem ser eficientes para diminuir a incidência de demência / INTRODUCTION: Recently, cardiovascular risk factors (CVRF) and cardiac diseases have been associated with dementia, Alzheimer disease (AD) and vascular dementia (VD). The aim of this study was to investigate the association between anatomically-proven cardiovascular disease and dementia, defined by clinical, neuropathological and clinicopathological criteria. METHODS: This was a cross-sectional study using material drawn from the Human Brain Bank of the Aging Brain Study Group. Carotid artery and Circle of Willis (CW) atherosclerosis as well as myocardial hypertrophy were evaluated in autopsy material and compared for the prevalence of dementia. Demographics and CVRF were also compared for the presence of dementia. This was defined by three criteria: (1) clinical according to cognitive scales applied to the informant of the deceased individual; (2) neuropathological according to accepted criteria for the classification of AD; (3) clinicopathological according to cognitive evaluation and the presence of AD and VD-associated cerebral lesions. RESULTS: The clinical study included 603 individuals older than 50 years, who underwent cognitive and cardiovascular evaluation. Dementia was found to be associated with a high degree (75%) of obstruction in carotid arteries, lower heart weight and thinner left ventricle wall. Individuals with clinically-defined dementia were older and had more informant-reported strokes, greater physical inactivity and heart failure and lower body mass index than subjects without dementia. The neuropathological study involved 183 individuals who were evaluated and divided into three groups: control group (n=124), AD (n=31) and VD (n=28). Individuals with AD showed a higher degree of obstruction75% in the carotid arteries than controls. Subjects with VD, besides presenting greater severity of carotid atherosclerosis, also had a greater degree of obstruction in the arteries of the CW than controls. Regarding demographics and CVRF, age was higher in individuals with AD and VD compared to controls, while informant-reported stroke was more prevalent among individuals with VD. The clinicopathological study included 124 control individuals, 12 patients with asymptomatic brain disease (ABD) and 47 demented subjects. Greater severity of carotid and CW artery atherosclerosis was observed in individuals with dementia compared to controls. In terms of demographics and CVRF, individuals with ABD were older than control individuals. Years of education were higher in subjects with ABD compared to controls and informant-reported stroke was more prevalent among demented persons than controls. CONCLUSIONS: Cardiovascular disease, particularly carotid artery and CW atherosclerosis, are associated with higher risk for dementia. Preventive measures aimed at slowing the progression of atherosclerosis may be effective in decreasing the incidence of dementia
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Ocorrência de bactérias periodontais em ateromas coletados de artéria coronária de pacientes portadores de periodontite crônica / Occurrence of periodontal bacteria in atheroma coronary arteries from patients with chronic periodontitisSilvia Linard Marcelino 25 August 2008 (has links)
Hoje em dia existe um consenso de que a prevenção e o tratamento de doenças periodontais são importantes na redução de mortalidade e morbidade associadas à doença cardíaca, e uma correlação entre aterosclerose e doença periodontal ainda é desconhecida. Neste estudo, a presença de Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Campylobacter rectus e Enterococcus faecalis em placas de ateroma de artérias coronárias foram detectadas. Trinta pacientes programados para endarterectomia, 28 pacientes com periodontite crônica e 2 sem doença periodontal foram incluídos no estudo. DNA bacteriano foram extraídos dos ateromas e a presença de bactérias periodontais foram detectadas através da reação em cadeia da polimerase. DNA bacteriano periodontal foi encontrado em 28 amostras de ateroma de pacientes periodontais: P. gingivalis em 14 (50%); P. nigrescens em 4 (14,3%), P. intermedia em 3 (10,7%); E. faecalis em 3 (10,7%), T. forsythia em 2 (7,1%); A. actinomycetemcomitans em 2 (7,1%); C. rectus em 2 (7,1%); T. denticola em 1 (3,6%); e P. endodontalis em 1 (3,6%). Fusobacterium nucleatum não foi encontrado em nenhuma das amostras analisadas. Em duas amostras de ateroma de pacientes sem doença periodontal, P. gingivalis e E. faecalis foram observadas em uma amostra e P. intermedia em ambas as amostras. Nossos resultados sugerem que a presença de P. gingivalis em ateroma de artérias coronárias pode apresentar um envolvimento com aterosclerose e parecendo ser um microrganismo da relação aterosclerose e periodontite crônica. / Nowadays there is a consensus that prevention and treatment of periodontal diseases are important in the reduction of mortality and morbidity associated to cardiovascular diseases, and a correlation between atherosclerosis and periodontal disease is still unclear. In this study, the presence of Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Campylobacter rectus and Enterococcus faecalis in atheroma plaques from coronary arteries was determined. Thirty patients scheduled for endarterectomy, 28 patients with chronic periodontitis and 2 without periodontal diseases were included in this study. Bacterial DNA was extracted from atheroma and periodontal bacteria detection was done by polymerase chain reaction. Periodontal bacterial DNA was found in 28 atheroma samples from periodontal patients: P. gingivalis in 14 (50%); P. nigrescens in 4 (14.3%); P. intermedia in 3 (10.7%); E. faecalis in 3 (10.7%), T. forsythia in 2 (7.1%); A. actinomycetemcomitans in 2 (7.1%); C. rectus in 2 (7.1%); T. denticola in 1 (3.6%); and P. endodontalis in 1 (3.6%) samples. Fusobacterium nucleatum was not detected in any atheroma analyzed. In two atheroma samples from patients without periodontal disease, P. gingivalis and E. faecalis were observed in one sample and P. intermedia in both samples. Our results suggest that the presence of P. gingivalis in atheroma from coronary arteries may be involved in atherosclerosis, and it appears to be a relationship microorganism atherosclerosis and chronic periodontitis.
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2-D and 3-D high frame-rate Pulse Wave Imaging for the characterization of focal vascular diseaseApostolakis, Iason Zacharias January 2018 (has links)
Cardiovascular diseases are major causes of morbidity and mortality in Western-style populations. Atherosclerosis and Abdominal Aortic Aneurysms (AAAs) are two prevalent vascular diseases that may progress without symptoms and contribute to acute cardiovascular events such as stroke and AAA rupture, which are consistently among the leading causes of death worldwide. The imaging methods used in the diagnosis of these diseases, have been reported to present several limitations. Given that both are associated with mechanical changes in the arterial wall, imaging of the arterial mechanical properties may improve early disease detection and patient care.
Pulse wave velocity (PWV) refers to the velocity at which arterial waves generated by ventricular ejection travel along the arterial tree. PWV is a surrogate marker of arterial stiffness linked to cardiovascular mortality. The foot-to-foot method that is typically used to calculate PWV suffers from errors of distance measurements and time-delay measurements. Additionally, a single PWV estimate is provided over a relatively long distance, thus inherently lacking the capability to provide regional arterial stiffness measurements. Pulse Wave Imaging (PWI) is a noninvasive, ultrasound-based technique for imaging the propagation of pulse waves along the wall of major arteries and providing a regional PWV value for the imaged artery.
The aim of this work was to enable PWI to provide more localized PWV and stiffness measurements within the imaged arterial segment and to further extend it into a 2-D and 3-D technique for the detection and monitoring of focal vascular disease at high temporal and spatial resolution. The improved modality was integrated with blood flow imaging modalities aiming to render PWI a comprehensive methodology for the study of arterial biomechanics in vivo.
Spatial information was increased with the introduction of piecewise PWI. This novel technique was used to measure PWV within small sub-regions of the imaged vessel in murine aneurysmal (n = 8) and atherosclerotic aortas (n = 11) in vivo. It provided PWV and stiffness maps while capturing the progressive arterial stiffening caused by atherosclerosis. PWI was further augmented with a sophisticated adaptive algorithm, enabling it to optimally partition the imaged artery into relatively homogeneous segments, automatically isolating arterial stiffness inhomogeneities. Adaptive PWI was validated in silicone phantoms consisting of segments of varying stiffness and then tested in murine aortas in vivo.
Subsequently, the conventional tradeoff between spatial and temporal resolution was addressed with a plane wave compounding implementation of PWI, allowing the acquisition of full field of view frames at over 2000 Hz. A GPU-accelerated PWI post-processing framework was developed for the processing of the big bulk of generated data. The parameters of coherent compounding were optimized in vivo. The optimized sequences were then used in the clinic to assess the mechanical properties of atherosclerotic carotids (n=10) and carotids of patients after endarterectomy (n=7), a procedure to remove the plaque and restore blood flow to the brain. In the case of atherosclerotic patients undergoing carotid endarterectomy, the results were compared against the histology of the excised plaques. Investigation of the mechanical properties of plaques was also conducted for the first time with a high-frequency transducer (18.5 MHz).
Additionally, 4-D PWI was introduced, utilizing high frame rate 3-D plane wave acquisitions with a 2-D matrix array transducer (16x16 elements, 2.5 MHz). A novel methodology for PWV estimation along the direction of pulse wave propagation was implemented and validated in silicone phantoms. 4-D PWI provided comprehensive views of the pulse wave propagation in a plaque phantom and the results were compared against conventional PWI. Finally, its feasibility was tested in the carotid arteries of healthy human subjects (n=6). PWVs derived in 3-D were within the physiological range and showed good agreement with the results of conventional PWI.
Finally, PWI was integrated with flow imaging modalities (Color and Vector Doppler). Thus, full field-of-view, high frame-rate, simultaneous and co-localized imaging of the arterial wall dynamics and color flow as well as 2-D vector flow was implemented. The feasibility of both techniques was tested in healthy subjects (n=6) in vivo. The relationship between the timings of the flow and wall velocities was investigated at multiple locations of the imaged artery. Vector flow velocities were found to be aligned with the vessel’s centerline during peak systole in the common carotid artery and interesting flow patterns were revealed in the case of the carotid bifurcation
Consequently, with the aforementioned improvements and the inclusion of 3-D imaging, PWI is expected to provide comprehensive information on the mechanical properties of pathological arteries, providing clinicians with a powerful tool for the early detection of vascular abnormalities undetectable on the B-mode, while also enabling the monitoring of fully developed vascular pathology and of the recovery of post-operated vessels.
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Prevalência de aterosclerose de carótida e fatores associados em mulheres a partir do climatério / Prevalence and predictors of carotid atherosclerosis in pre- and post-menopausal womenBarros, Isly Maria Lucena de 19 August 2014 (has links)
Introdução: As doenças cardiovasculares permanecem como a principal causa de morbimortalidade entre as mulheres no Brasil e no mundo. Estratégias de prevenção primária baseadas na detecção dos fatores de risco tradicionais para aterosclerose, têm sido pouco eficazes para reduzir as altas taxas de mortalidade nessa população. O presente estudo tem como objetivo primário detectar e quantificar a presença de aterosclerose na sua fase subclínica, em mulheres climatéricas e pós-menopausadas. Métodos: Foram estudadas 823 mulheres de 45 a 65 anos de idade (idade média 54,3 ± 5,3 anos), no período peri e pós-menopausa, sem doença cardiovascular conhecida, ou em uso de terapia de reposição hormonal, residentes em Recife, Nordeste do Brasil. Todas foram submetidas a avaliação clínica e dosagens bioquímicas, que incluíram os níveis de glicose, lipídios, proteína C-reativa, hormônio folículo-estimulante, adiponectina e aldosterona. Ultrassonografia modo B foi utilizada na avaliação carotídea; medidas da espessura íntima média carotídea (EIMC) foram determinadas na parede posterior da artéria carótida comum (ACC) utilizando-se um \"software\" de leitura automatizada; aterosclerose carotídea foi definida quando da presença de placa carotídea e/ou EIMC > 1mm. Resultados: De 823 mulheres, 10,2% eram fumantes, 58% tinham hipertensão e 9,9% eram diabéticas. A prevalência de doença aterosclerótica subclínica entre a população analisada foi de 12,7%, e a média da EIMC foi de 0,645 ± 0,124 milímetros. Na análise univariada, foram detectadas associações significativas entre presença de aterosclerose carotídea e: a idade (p < 0,001), o fumo (p=0,014), a hipertensão (p=0,002), a pressão arterial sistólica (p=0,003), o colesterol total (p=0,001) e o LDL-colesterol (p=0,001). No modelo ajustado, a idade (p < 0,001), o fumo (p=0,001), a pressão arterial sistólica (p=0,030) e o colesterol total (p=0,008) se correlacionaram de forma significativa e independente com a aterosclerose carotídea. Conclusão: O presente estudo revelou uma alta prevalência de aterosclerose carotídea entre as mulheres brasileiras a partir do climatério. Assim como a idade, os fatores de risco clássicos se correlacionaram de forma independente com aterosclerose carotídea. Esses resultados são de particular relevância, visto que as estratégias para redução do risco cardiovascular são baseadas em modelos de predição de risco onde as mulheres são frequentemente classificadas no grupo de baixo risco cardiovascular. Consequentemente, as oportunidades de envolvê-las mais cedo na prevenção da doença aterosclerótica são muitas vezes perdidas / Aims: Cardiovascular diseases continue to be the main cause of morbidity and mortality among women in Brazil and worldwide. Strategies of primary prevention, based on the detection of traditional risk factors for atherosclerosis, have had a small impact in reducing the high rates of mortality in this population. Therefore, the main purpose of this study was to analyse the prevalence of subclinical carotid atherosclerosis in peri- and postmenopausal women. Methods: We studied 823 peri- and postmenopausal women, 45 to 65 years-old (mean age 54.3±5.3 years), from Recife city, without known cardiovascular disease and hormone therapy utilization. All of them were submitted to a careful medical evaluation, and biochemical analyses that included glucose and lipids levels, C-reactive protein, follicle-stimulating hormone, adiponectin and aldosterone. B-mode ultrasound was utilized for carotid evaluations; intima-media thickness (IMT) measures were determined on the far wall common carotid artery (CCA) with automated reading software; presence of carotid atherosclerosis was defined as either the presence of plaque and/or IMT >= 1.00mm. Results: Of the 823 women, 10.2% were current smokers, 58% had hypertension and 9.9% were diabetics. The prevalence of subclinical atherosclerotic disease among the analyzed population was 12.7%, and the mean CCA-IMT was 0.645±0.124 mm. By univariate analyses, a positive and statistically significant correlation was found between carotid atherosclerosis and age (p < 0.001), current smoker (p=0.014), hypertension (p=0.002), systolic blood pressure (p=0.003), total cholesterol (p=0.001) and LDL cholesterol (p=0.001). In the adjusted model, age (p < 0.001), current smoker (p=0.001), systolic blood pressure (p=0.030) and total cholesterol (p=0.008), remained correlating significantly and independently with carotid atherosclerosis. Conclusion: Our study showed a high prevalence of carotid atherosclerosis among asymptomatic pre- and post-menopausal Brazilian women. As well as age, classic risk factors correlated independently with carotid atherosclerosis. These findings are of particular relevance as strategies for reducing cardiovascular risk are based on risk prediction models in which women are often classified as having low cardiovascular risk, and opportunities for engaging them in prevention at a younger age are very often missed
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Submaximal Exercise Capacity is Associated with Moderate-to-Vigorous Physical Activity in Children with Complex Congenital Heart DiseaseKung, Tyler 02 May 2019 (has links)
Background: Children with complex congenital heart disease (CHD) are exposed to cyanosis from birth until their surgical repair and are often not expected to participate in physical activities to the same extent as healthy peers because of a limited maximal exercise capacity (V̇O2max). Despite limitations in V̇O2max, these children may still have the capacity to perform most daily physical activity because it requires only a submaximal effort. The purpose of this research was to examine the relationships between submaximal exercise capacity, daily physical activity and cyanosis exposure, in children with complex CHD.
Methods: Children with a single functioning ventricle (Fontan), tetralogy of Fallot or transposition of the great arteries, 10 to 17 years old were deemed eligible. The Bruce treadmill protocol with breath-by-breath analysis of oxygen consumption was used to assess submaximal exercise capacity. Five measures of submaximal exercise capacity were evaluated: energy consumption (V̇O2) at the ventilatory threshold, V̇O2 at a heart rate of 130 beats per minute (bpm), metabolic equivalents (METs) at ventilatory threshold, METs at 130 bpm and heart rate at stage 1 of the Bruce protocol. Moderate-to vigorous physical activity (MVPA) was measured (Actical accelerometer with 15 second epochs) for 7 consecutive days. Exposure to cyanosis was calculated by subtracting the child’s date of birth from the date of surgical repair.
Results: Participants were children with a Fontan single ventricle (n=5), tetralogy of Fallot (n=4) or transposition of the great arteries (n=7). Daily physical activity was positively associated with V̇O2 at ventilatory threshold (r = 0.78, n = 16, p = < 0.01) and V̇O2 at a heart rate of 130 bpm (r = 0.61, n = 16, p = 0.01). Children who did more than 60 minutes of physical activity per day (n=4) achieved significantly higher energy expenditure before reaching ventilatory threshold, (95% CI of the difference [8.23, 24.85], t(14) = 4.27, p = < 0.01) and at a heart rate of 130 bpm (95% CI of the difference [1.61, 14.33], t(14) = 2.69, p = 0.02). Lastly, V̇O2 at ventilatory threshold was negatively associated with days spent in cyanosis (r = .55, n = 16, p = 0.03), Conclusion: Higher V̇O2 at ventilatory threshold and V̇O2 at a heart rate of 130 bpm was associated with more daily minutes spent in moderate-to-vigorous physical activity. These results suggest that children who meet the recommended 60 minutes of MVPA would have a higher submaximal exercise capacity (V̇O2 at ventilatory threshold or a heart rate of 130 bpm), than children who did not meet the MVPA guidelines. Lastly, children who were exposed to cyanosis for a longer period of time had a lower submaximal V̇O2 at ventilatory threshold, than children who were exposed to cyanosis for a shorter period of time.
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Avaliação ultrassonográfica da artéria carótida comum em equinos da raça Quarto de Milha /Aguiar, Adriana Cristina Saldanha de. January 2015 (has links)
Orientador: Vânia de Vasconcelos Machado / Coorientador: Noeme Sousa Rocha / Banca: Priscila Macedo de Souza / Banca: Rogério Martins Amorim / Resumo: A artéria carótida comum em equinos se trifurca com algumas variações anatômicas e é o principal vaso que fornece sangue arterial para o cérebro, sendo que é conhecido que sua oclusão causa lesões encefálicas em ratos e humanos. Há muito pouca literatura a respeito de estudos anatômicos e ultrassonográficos desse vaso nessa espécie. Esse estudo avaliou a artéria carótida comum de 50 equinos da raça Quarto de Milha em diferentes idades, divididos em três grupos (grupo I: >2anos, n=14; grupo II: 3-10 anos, n=21; grupo III 15-30 anos, n=15), e obteve valores de referencia para espessura intima-media (EIM), índice de resistividade (IR), índice de pulsatilidade (IP) e diâmetro para ambas artérias carótidas comuns. Os exames foram feitos utilizando um transdutor de 18 MHz no sulco jugular, na altura de C5-C6. O diâmetro esquerdo médio foi de 8,71 ± 1,09 mm para o grupo I; 10,11 ± 0,72 mm para o grupo II e 10,72 ± 0,96 mm para o grupo III. O diâmetro direito médio foi de 8,92 ± 1,24 mm para o grupo I; 10,96 ± 1,06 mm para o grupo II e 11,76 ± 1,07 mm para o grupo III. A EIM foi de 0,90 ± 0,15 mm; 1,02 ± 0,09 mm e 0,97 ± 0,10 mm para os grupos I, II e III, respectivamente. Os valores médios de IR e IP obtidos foram 0,75 ± 0,07 e 1,63 ± 0,33 para o grupo I; 0,81 ± 0,06 e 2,08 ± 0,46 para o grupo II; 0,90 ± 0,10 e 3,20 ± 0,74 para o III, respectivamente. As variáveis IR, IP e EIM não são influenciadas por sexo ou lado, mas sim por idade. Já o diâmetro está correlacionado com o lado e idade, sendo sempre maior do lado direito / Abstract: Common carotid artery in horses trifurcates with some anatomical variations and it is the main supply of arterial blood to the brain. It is known that carotid occlusion can cause encephalic lesions in rats and humans. There are few studies on this vessel, including ultrasonografic evaluation of his vessel in this species. This study evaluated the common carotid artery in 50 American Quarter horses with different ages, separated into three groups (group I: >2years, n=14; group II: 3-10 years, n=21; group III 15-30 years, n=15), and reference values for intima-media thickness (IMT), resistivity index (RI), pulsatility index (PI) and diameter were obtained for both arteries. Exam was performed using an 18 MHz transducer on jugular groove, on level of C5-C6. Mean left diameter was 8.71 ± 1.09 mm for group I; 10.11 ± 0.72 mm for group II and 10.72 ± 0.96 mm for group III. Right diameter was 8.92 ± 1.24 mm for group I; 10.96 ± 1.06 mm for group II and 11.76 ± 1.07 mm for group III. IMT was 0.90 ± 0.15 mm; 1.02 ± 0.09 mm and 0.97 ± 0.10 mm for groups I, II and III, respectively. Mean RI and PI obtained were 0.75 ± 0.07 and 1.63 ± 0.33 for group I; 0.81 ± 0.06 and 2.08 ± 0.46 for group II; 0.90 ± 0.10 and 3.20 ± 0.74 for group III, respectively. The variables RI, PI and IMT are not influenced by gender or side, but were by age. Diameter was influenced by both, age and side, and right diameter was always greater than the left / Mestre
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Avaliação do complexo íntima-média da carótida pela ultrassonografia e sua relação com o escore Pathobiological Determinants of Atherosclerosis in YouthRamos, Thacira Dantas Almeida 15 October 2014 (has links)
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Previous issue date: 2014-10-15 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Atherosclerosis begins in childhood and adolescence and results in mortality or
high-morbidity conditions such as myocardial infarction, cerebrovascular accident and
peripheral artery disease. In order to identify individuals with a high probability of developing
cardiovascular disease, risk scores for cardiovascular risk stratification were developed. In
adolescence, the Pathobiological Determinants of Atherosclerosis in Youth score is used, but
not much in Brazil. The thickening of the intima-media complex of the carotid artery, as
assessed by ultrasonography, is regarded as diagnostic of subclinical atherosclerotic disease.
However, there is no consensus in the literature on a cutoff to consider the presence of this
condition. The goal of this study was to evaluate the prevalence of thickening of intima-media
complex of the carotid, by means of the 75th percentile and Z-score, on high school
adolescents and its relationship to the PDAY score. METHOD: Cross-sectional, quantitative
study conducted in public high schools in Campina Grande, Paraíba, Brazil, from September
2012 to June 2013, involving 512 adolescents between 15 and 19 years of age. Sociodemographic
(age,
gender,
skin
color,
socioeconomic
status
and
maternal
education);
clinical,
anthropometric,
biochemical and behavioral variables, which comprise the PDAY score
(fasting glucose, HbA1c, HDL and N-HDL cholesterol, blood pressure, BMI, and smoking),
were evaluated. The thickening of the intima-media complex of the carotid artery was
measured by ultrasound examination, with two cutoff points adopted: greater than or equal to
75th percentile values and greater than or equal to Z-score 2+. To evaluate the association
between the thickening of intima-media complex of the carotid and socio-demographic,
clinical, anthropometric, biochemical, and the PDAY score, the chi-square test was
performed. To verify the independent association of each characteristic with the presence or
absence of thickening of the intima-media layer, considered a dichotomous dependent
variable, and the independent variables (components of the PDAY score, smoking and
nutritional status score) a multivariate logistic regression model was developed. Analyses
were performed in SPSS 22.0 and the significance level of 5% was considered. RESULTS:
The thickening of the carotid artery was present in 25.0% when the 75th percentile cutoff was
used, and 4.3% when the Z-score was used, and high cardiovascular risk was observed in
10.1% of the adolescents studied. Regardless of the criteria utilized, there was no association
between carotid thickness and sex (p> 0.05). When assessed by percentile, there was only an
association with one of its components, BMI> 30 (p= 0.005). On the other hand, the elevated
measurements of intima-media complex of the carotid, using the Z-score, were associated
with elevated systolic blood pressure (p= 0.024), high non-HDL cholesterol (p= 0.039) and
those with a PDAY score classified as high risk (p= 0.003). After adjusting the model, high
PDAY score proved to be an independent risk factor for the presence of thickening of the
carotid artery, with a 4 times greater chance of having this condition when compared with
those at low risk. CONCLUSION: The evaluation of thickening of intima-media complex of
carotid by ultrasonography, using as a cutoff Z-score, was associated with the Pathobiological Determinants of Atherosclerosis in Youth score. / A doença aterosclerótica inicia-se na infância e adolescência tendo como
desfecho, condições de alta morbi-mortalidade como infarto do miocárdio, acidente vascular
encefálico e doença arterial periférica. Na busca de identificar indivíduos com alta
probabilidade em desenvolver doença cardiovascular, foram elaborados os escores de risco
para estratificação do risco cardiovascular. Na adolescência existe o escore Pathobiological
Determinants of Atherosclerosis in Youth, pouco utilizado no Brasil. O espessamento do
complexo íntima-média da carótida, avaliado pela ultrassonografia, é tido como achado de
doença aterosclerótica subclínica. Porém, não existe consenso na literatura sobre um ponte de
corte para considerar a presença dessa condição. O estudo teve como objetivo avaliar a
prevalência do espessamento do complexo íntima-média da carótida, através do percentil 75 e
do escore-Z, em adolescentes escolares e sua relação com o escore PDAY. MÉTODO:
Estudo transversal, quantitativo, desenvolvido em escolas públicas de ensino médio de
Campina Grande, Paraíba, Brasil, durante setembro de 2012 a junho de 2013, envolvendo 512
adolescentes entre 15 e 19 anos. Foram avaliadas variáveis sócio-demográficas (idade, sexo,
cor da pele, classe econômica e escolaridade materna); clínicas, antropométricas, bioquímicas
e comportamental, que compõem o escore PDAY (glicemia de jejum, HbA1c, colesterol HDL
e N-HDL, pressão arterial, IMC e tabagismo). O espessamento do complexo íntima-média da
carótida foi avaliado através de exame ultrassonográfico sendo adotado dois pontos de corte:
valores maiores ou iguais ao percentil 75 e valores maiores ou iguais a escore-Z 2+. Para
avaliação de associação entre o espessamento do complexo íntima-média da carótida e
variáveis sócio-demográficas, clínicas, antropométricas, bioquímicas e o escore PDAY foi
realizado o teste do qui-quadrado. Para verificar a associação independente de cada
característica com a presença ou ausência do espessamento da camada íntima-média,
considerada como variável dependente dicotômica, e as variáveis independentes
(componentes do escore PDAY, tabagismo e estado nutricional) foi construído um modelo de
regressão logística multivariado. As análises foram realizadas no SPSS 22.0 e considerou-se
um nível de significância de 5%. RESULTADOS: O espessamento da carótida esteve
presente em 25,0% quando utilizado como ponto de corte o percentil 75, e de 4,3% pelo
escore-Z, e o risco cardiovascular elevado em 10,1% dos adolescentes avaliados.
Independente do critério observado, não houve associação do espessamento da carótida com o
sexo (p>0,05). Quando avaliado pelo percentil, mostrou associação apenas a um dos seus
componentes, o IMC>30 (p=0,005). Por outro lado, as medidas elevadas do complexo íntimamédia
da carótida, pelo escore-Z, estiveram associadas a pressão arterial sistólica elevada
(p=0,024), colesterol não-HDL elevado (p=0,039) e aqueles com o escore PDAY classificado
como alto risco (p=0,003). Após ajuste do modelo, o escore PDAY alto mostrou-se um fator
de risco independente para a presença de espessamento da carótida, com uma chance 4 vezes
maior de apresentar essa condição quando comparado com aqueles de baixo risco.
CONCLUSÃO: A avaliação do espessamento do complexo íntima-média da carótida pela
ultrassonografia utilizando como ponto de corte o escore-Z, apresentou associação com o
escore Pathobiological Determinants of Atherosclerosis in Youth.
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