This study used an in situ heart preparation to analyze the power and work of spontaneously beating hearts of four anurans (R. marina, L. catesbeianus, X. laevis, P. edulis) and three urodeles (N. maculosus, A. tigrinum, A. tridactylum) in order to elucidate the meaning of relative ventricle mass (RVM) in terms of specific cardiac performance variables. This study also tests two hypotheses: 1) the ventricles of terrestrial species (R. marina, P. edulis, A. tigrinum) of amphibians are capable of greater maximum power outputs (Pmax) compared to aquatic species (X. laevis, A. tridactylum, N. maculosus, L. catesbeianus) and, 2) the ventricles of Anuran species (R. marina, P. edulis, L. catesbeianus, X. laevis) are capable of greater maximum power output compared to aquatic species (A. tigrinum, A. tridactylum, N. maculosus). The data supported both hypotheses. RVM was significantly correlated with Pmax, stroke volume, cardiac output, afterload at Pmax, and preload at Pmax. Preload at Pmax and afterload at Pmax also correlated very closely with each other, suggesting that an increase blood volume and/or increased modulation of sympathetic tone may influence interspecific variation RVM and may have played a role in supporting higher rates of metabolism, as well as dealing with hypovolemic stresses of life on land.

Made available in DSpace on 2015-03-26T13:30:54Z (GMT). No. of bitstreams: 1 01 - capa_resultados.pdf: 56161 bytes, checksum: 89932d2a2d5a8cad69600a6e72a9cae4 (MD5) Previous issue date: 2007-02-23 / The peritrophic membrane forms a thin layer that lines the midgut of the insects isolating the food of the midgut epithelium. The peritrophic membrane has mechanical function as well as a physical barrier against microorganisms and performs some physiological roles during food digestion. In bees the origin of peritrophic membrane is unclear and this work described the ultrastructure of the anterior midgut region in corbiculate bees for the understanding of the function of this section of the digestive tract. The species studied were Apis mellifera, Melipona quadrifasciata nanthidioides, Bombus morio and Euglossa. townsendi. The results showed that the anterior midgut region is a specialized strucuture only in Meliponini that has cells tall and thin. Meanwhile in Melipona quadrifasciata anthidioides and the others studied species cells of this midgut region show ultrastrucutural features of digestive cells. The basal plasma membrane infoldings have many openings to the haemocel, suggesting an absorption role in this midgut region. The anterior midgut region of bees is characterized for the presence of the cardiac valve, a foregut section that protrudes into the midgut. The cells of the anterior midgut region of Meliponini (cardia), despite be a section anatomically and histologically differentiated, has cells with ultrastructure featrures similar to those of Bombini and Apini, and they may play a role in water and food absorption. / A membrana peritrófica forma uma camada fina que reveste o intestino médio dos insetos separando o alimento do epitélio do intestino, tem função mecânica e função de barreira física contra infestação de microorganismos. Considerando que a membrana peritrófica tem sua origem discutida nas abelhas este trabalho analisou a ultra-estrutura da porção anterior do intestino médio em abelhas corbiculadas para a compreensão da função desta região do trato digestivo. Foram estudadas espécies de abelhas corbiculadas: Apis mellifera, Melipona quadrifasciata anthidioides, Bombus morio e Euglossa townsendi. Os resultados ultra-estruturais da porção anterior do ventrículo das abelhas corbiculadas obtidos neste trabalho mostram que esta região é diferenciada apenas em Meliponini, que se caracteriza por células altas e finas. Entretanto, tanto em Melipona quadrifasciata anthidioides e nas demais espécies estudadas estas células apresentam características típicas de células digestivas. O comprimento dos canais formado pelas invaginações da membrana plasmática basal apresenta muitas aberturas para a hemocela, indicando atividade absortiva nesta região do intestino médio. A porção anterior do intestino médio de abelhas é caracterizada pela presença da válvula cárdiaca, a qual corresponde a uma porção do estomodeu que se projeta no interior do intestino. As células da porção anterior do intestino médio de Meliponini (cárdia) apesar de ser uma região diferenciada anatomicamente e histologicamente é ultra-estruturalmente semelhante àquelas células da porção anterior do ventrículo de Bombini e Apini, estando envolvidas na absorção de água do alimento.

Orientador: Wilson Nadruz Júnior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T23:44:37Z (GMT). No. of bitstreams: 1 Sales_MariaLilian_D.pdf: 3937457 bytes, checksum: 1aca22e05bdd5e09c3f3e53c2841451e (MD5) Previous issue date: 2010 / Resumo: Estudos experimentais revelaram que a inibição de componentes da via de sinalização celular regulada pelos Toll-Like Receptors (TLRs) pode atenuar a hipertrofia cardíaca em animais submetidos à sobrecarga pressora. O objetivo deste estudo foi investigar a influência dos polimorfismos Asp299Gly do TLR4 e Pro249Ser do TLR6 sobre a estrutura do ventrículo esquerdo (VE) em indivíduos hipertensos. Foram estudados 443 pacientes por meio de avaliação clínica, laboratorial e ecocardiográfica, enquanto que os polimorfismos foram detectados por reação de polimerase em cadeia/enzima de restrição. Ademais, monócitos obtidos de sangue periférico de pacientes hipertensos foram estimulados in vitro com LPS (agonista de TLR4) e zimosan (agonista de TLR6) e a produção de interleucina-6 e fator de necrose tumoral-alfa (TNF-alfa) foi avaliada de acordo com a presença da variante Asp299Gly do TLR4 e Pro249Ser do TLR6. Mulheres que carregavam o alelo TLR4 299Gly apresentaram menor espessura de parede posterior do VE, menor espessura de septo, menor índice de massa do VE e reduzida prevalência de hipertrofia cardíaca. Mulheres homozigotas para TLR6 249Ser apresentaram menor espessura da parede do VE e menor espessura relativa da parede do VE em relação às mulheres com os genótipos Pro/Ser e Pro/Pro. Estes achados foram confirmados por análise de regressão linear múltipla, que incluiu idade, pressão arterial sistólica e diastólica, índice de massa corpórea, menopausa, diabetes mellitus e uso de antihipertensivos como fatores confundidores. Por fim, estudos funcionais in vitro revelaram que monócitos de homens e mulheres que apresentaram o alelo TLR4 299Gly tiveram menor produção de interleucina-6 após estímulo com LPS e a presença do alelo TLR6 249Ser em homozigose esteve associada a uma menor produção de interleucina-6 e TNF-alfa após estímulo com zimosan apenas nos monócitos extraídos de mulheres hipertensas. De maneira geral, esses dados sugerem que pode haver uma interação entre gêneros, polimorfismos dos receptores Toll-like e fenótipo do VE em indivíduos hipertensos. Sob esta perspectiva, estudos longitudinais são necessários para avaliar o impacto destes polimorfismos sobre o risco cardiovascular em mulheres hipertensas / Abstract: Experimental studies have shown that inhibition of components of cell signaling pathway regulated by Toll-Like Receptors (TLRs) can reduce cardiac hypertrophy in animals subjected to pressure overload. The aim of this study was to investigate the influence of the polymorphisms TLR4 Asp299Gly and TLR6 Pro249Ser on the structure of the left ventricle in hypertensive subjects. We studied 443 patients by clinical, laboratory and echocardiographic, while polymorphisms were detected by the polymerase chain / restriction enzyme. Moreover, monocytes obtained from peripheral blood of hypertensive patients were stimulated in vitro with LPS (TLR4 agonist) and zymosan (TLR6 agonist) and the production of interleukin-6 and tumor necrosis factor-alpha (TNF-alpha) was assessed according to the presence of the Asp299Gly variant of TLR4 and Pro249Ser of TLR6. Women who carried the TLR4 299Gly allele had lower posterior wall thickness, thinner septum, a lower rate of left ventricular mass and reduced prevalence of cardiac hypertrophy. Women homozygous for TLR6 249Ser had lower posterior wall thickness and relative wall thickness, compared to women with the genotype Pro/Ser and Pro/Pro. These findings were confirmed by analysis of multiple linear regression that included age, systolic and diastolic blood pressure, body mass index, menopause, diabetes mellitus and use of antihypertensive drugs as confounding factors. Finally, in vitro functional studies revealed that monocytes from men and women who harbored the TLR4 299Gly allele had lower production of interleukin-6 after stimulation with LPS and the presence of homozygous 249Ser allele was associated with a lower production of Interleukin-6 and TNF-alpha after stimulation with zymosan only in monocytes hypertensive women. These data suggest that there may be an interaction between gender, polymorphisms of Toll-like receptors and ventricular phenotype in hypertensive subjects. In this regard, longitudinal studies are needed to assess the impact of these polymorphisms on the cardiovascular risk of hypertensive women / Doutorado / Clinica Medica / Doutor em Clínica Médica

Orientadores: Carlos Kenichi Suzuki, Aron José Pazin de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-21T07:29:25Z (GMT). No. of bitstreams: 1 Silva_BrunoUtiyamada_M.pdf: 3089036 bytes, checksum: 01d1bb268591e2388a9bb34046fbd188 (MD5) Previous issue date: 2012 / Resumo: Neste trabalho, foi realizado um estudo experimental de uma Bomba de Sangue Ápice Ventricular (BSAV) para sua análise como um dispositivo de assistência ventricular. Este estudo faz parte do desenvolvimento desta bomba e serviu como fundamentação na evolução do projeto. A BSAV é uma bomba de sangue centrífuga de fluxo contínuo, para ser utilizada como dispositivo de assistência ventricular em pacientes com doenças cardíacas crônicas. Foi realizado um estudo de posicionamento anatômico, onde a bomba foi implantada em um coração de um porco e não foram encontrados indícios de possíveis danos aos tecidos e órgãos circunvizinhos. Em seguida, foi feito um ensaio experimental, onde foi comparado o desempenho de protótipos com características distintas, visando sua otimização em relação ao desempenho hidrodinâmico. Também foi realizado um estudo para avaliação do trauma as células do sangue causado pela ação da bomba, no qual os resultados mostraram um baixo dano as células. A seguir, foi feito estudo com um protótipo conectado em um simulador cardiovascular híbrido (matemático e físico), onde este protótipo às condições simuladas de um sistema cardiovascular com insuficiência cardíaca. Com a BSAV conectada ao sistema obteve-se, uma melhora no fluxo de sangue, frequência cardíaca e pressão aórtica. Os resultados indicam que a BSAV é adequada para aplicação como dispositivo de assistência ventricular esquerda e é uma alternativa promissora no tratamento de pacientes com doenças cardíacas crônicas / Abstract: In this work an experimental study was realized with the Apico-Ventricular Blood Pump (AVBP) used as a ventricular assist device. This study is part of the device's development and the results were used for project evaluation and improvement. AVBP is a continuous flow centrifugal blood pump for ventricular assistance in chronic cardiac patients. Initially, an anatomic study was performed, in this study an AVBP prototype was implanted in a corpse of a pig, the clinical staff appointed, none damage to the nearby tissues and organs due to the contact with the device. Following step consists in an experimental hydrodynamic performance test. For this test the prototypes used had distinct specific construction characteristics variations among themselves, for device optimization, the performance of these different prototypes were compared, and the prototypes which presented a better performance had their characteristic adopted in the project. A study to determine the traumatic effect of the pump on blood cells was conducted, the results showed low damage to the blood cells. A hybrid mock loop circulation system (mathematical and physic) where the pump, was connected to a system with heart disease, was used. When the AVBP was inserted in the system, cardiac output, heart rate and aortic pressure went to normal values. All results indicated the performance of the AVBP as ventricular assist device, an alternative for treatment of patients with cardiac chronic diseases / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Introduction: Venoarterial extracorporeal membrane oxygenation (VA ECMO) is widely used in the treatment of circulatory failure, but repeatedly, its negative effects on the left ventricle (LV) have been observed. The purpose of this study is to assess the influence of ex- tracorporeal blood flow (EBF) on systemic hemodynamic changes and LV performance parameters during VA ECMO therapy of decompensated heart failure. Methods: Porcine models of low-output chronic and acute heart failure were developed by long-term fast cardiac pacing and coronary hypoxemia, respectively. Profound signs of circulatory decompensation were defined by reduced cardiac output and tissue hypoperfusion. Sub- sequently, under total anesthesia and artificial ventilation, VA ECMO was introduced. LV performance and organ specific parameters were recorded at different levels of EBF using an LV pressure-volume loop analysis, arterial flow probes on carotid and subclavian arteries, and transcutaneous probes positioned to measure cerebral and forelimb regional tissue oxygen saturations. Results: Conditions of severely decompensated heart failure led to systemic hypotension, low tissue and mixed venous oxygen saturations, and increase in LV end-diastolic pressure. By increasing the EBF from minimal flow to 5 L/min, we observed a...

In mammals, myocardial cell death due to infarction results in scar formation and little regenerative response. In contrast, zebrafish have a high capacity to regenerate the heart after surgical resection of myocardial tissue. However, whether zebrafish can also regenerate lesions caused by cell death has not been tested. Here, we present a simple method for induction of necrotic lesions in the adult zebrafish heart based on cryoinjury. Despite widespread tissue death and loss of cardiomyocytes caused by these lesions, zebrafish display a robust regenerative response, which results in substantial clearing of the necrotic tissue and little scar formation. The cellular mechanisms underlying regeneration appear to be similar to those activated in response to ventricular resection. In particular, the epicardium activates a developmental gene program, proliferates and covers the lesion. Concomitantly, mature uninjured cardiomyocytes become proliferative and invade the lesion. Our injury model will be a useful tool to study the molecular mechanisms of natural heart regeneration in response to necrotic cell death.

Master of Science / Department of Computing and Information Sciences / John Hatcliff / The Heart is a specialized muscle that contracts regularly and continuously, pumping blood to the body and the lungs. Heart’s natural Pacemaker, the SA node is responsible for this pumping action by causing a flow of electricity through the heart. These electrical impulses cause the atria and ventricles to contract and thereby pump the blood to different parts of the body. Malfunction of the SA node leads to a disturbance in the heart’s rhythm in which heart beats lower than 60 times a minute ending up with Bradycardia. It also leads to ventricular arrhythmia which disrupts the ability of the ventricles to pump blood effectively to the body. This can cause a loss of all blood pressure leading to cardiac arrest and eventually death. In order to restore the heart’s natural healthy rhythm, an artificial pacemaker is necessary. A Pacemaker adapts to the present condition of the heart and responds to the heart by either pacing or just sensing it. It paces whenever there is some problem in the heart’s electrical activity and inhibits the pace when there is a proper intrinsic beat. There are various modes in which Pacemaker can operate based on the condition of the heart. Ventricles and atria are individually paced in few modes such as VOO, VVT, VVI, AOO, AAT, and AAI and paced together in some modes such as DVI, DI, DDD, DDDR as per the requirement of the heart. The main goal of this report is to understand the various modes, their nomenclature, working strategy, developing the pseudo code and implementing different modes namely VOO, AOO, VVI, AAI, VVT and AAT modes using an academic, dual chamber pacemaker.

Objetivo: O principal propósito do estudo foi pesquisar a disfunção ventricular esquerda subclínica em pacientes com lúpus eritematoso sistêmico juvenil (LESJ) através da técnica de speckle-tracking bidimensional. Foi investigada ainda uma possível correlação entre o comprometimento da deformação miocárdica e o SLEDAI-2K (Systemic Lupus Erithematosus Disease Activity Index 2000), bem como a presença de fatores de risco cardiovascular, tanto tradicionais como ligados à doença. Métodos: 50 pacientes assintomáticos do ponto de vista cardiovascular e 50 controles saudáveis (14,74 vs. 14,82 anos, p=0.83) foram avaliados pelo ecocardiograma convencional e pelo speckle-tracking bidimensional. Resultados: Apesar da fração de ejeção normal, os pacientes apresentaram redução de todos os parâmetros de deformação miocárdica longitudinal e radial, quando comparados aos controles: strain de pico sistólico longitudinal [-20,3 (-11 a -26) vs. -22 (-17,8 a -30.4) %, p < 0,0001], strain rate de pico sistólico longitudinal [-1,19 ± 0,21 vs. -1,3 ± 0,25 s-1, p=0,0005], strain rate longitudinal na diástole precoce [1,7 (0,99 a 2,95) vs. 2 (1,08 a 3,00) s-1 , p=0,0034], strain de pico sistólico radial [33,09 ± 8,6 vs. 44,36 ± 8,72%, p < 0,0001], strain rate de pico sistólico radial [1,98 ± 0,53 vs. 2,49 ± 0,68 s-1, p < 0,0001] e strain rate radial na diástole precoce [-2,31 ± 0,88 vs. -2,75 ± 0,97 s-1, p=0,02]. O strain de pico sistólico circunferencial [-23,67 ± 3,46 vs. - 24,6 ± 2,86%, p=0,43] e o strain rate circunferencial na diástole precoce [2 (0,88 a 3,4) vs. 1,99 (1,19 a 3,7) s-1, p=0,88] foram semelhantes em pacientes e controles. Apenas o strain rate de pico sistólico circunferencial [-1,5 ± 0,3 vs. -1,6 ± 0,3 s-1, p=0,036] mostrou-se reduzido no LESJ. Uma correlação negativa foi identificada entre o strain de pico sistólico longitudinal e o SLEDAI-2K (r = - 0,52; p < 0,0001) e também o número de fatores de risco cardiovascular por paciente (r = -0,32, p=0,024). Conclusões: Foi evidenciada disfunção sistólica e diastólica subclínica de ventrículo esquerdo no LESJ através da técnica de speckle-tracking bidimensional. A atividade da doença e a exposição aos fatores de risco cardiovascular provavelmente contribuíram para o comprometimento da deformação miocárdica nesses pacientes / Objectives: The main purpose of the study was to investigate left ventricular (LV) subclinical systolic and diastolic dysfunction in childhood-onset systemic lupus erythematosus (c-SLE) patients using two-dimensional speckletracking (2DST) echocardiography. We also interrogated possible correlations between impairment of myocardial deformation and the SLE Disease Activity Index 2000 (SLEDAI-2K), as well as the presence of traditional and disease-related cardiovascular risk factors (CRFs). Method: A total of 50 asymptomatic patients and 50 controls (age 14.74 vs. 14.82 years, p = 0.83) were evaluated by standard and 2DST echocardiography. Results: Despite a normal ejection fraction (EF), there was reduction in all parameters of LV longitudinal and radial deformation in patients compared to controls: peak longitudinal systolic strain [-20.3 (-11 to -26) vs. -22 (-17.8 to -30.4)%, p < 0.0001], peak longitudinal systolic strain rate [-1.19 ± 0.21 vs. -1.3 ± 0.25 s-1, p = 0.0005], longitudinal strain rate in early diastole [1.7 (0.99-2.95) vs. 2 (1.08-3.00) s-1, p = 0.0034], peak radial systolic strain [33.09 ± 8.6 vs. 44.36 ± 8.72%, p < 0.0001], peak radial systolic strain rate [1.98 ± 0.53 vs. 2.49 ± 0.68 s-1, p < 0.0001], and radial strain rate in early diastole [-2.31 ± 0.88 vs. -2.75 ± 0.97 s-1, p = 0.02]. Peak circumferential systolic strain [- 23.67 ± 3.46 vs. -24.6 ± 2.86%, p=0.43] and circumferential strain in early diastole [2 (0,88 a 3,4) vs. 1,99 (1,19 a 3,7) s-1, p=0.88 ] were similar between patients and controls, although peak circumferential systolic strain rate [-1.5 ± 0.3 vs. -1.6 ± 0.3 s-1, p = 0.036] was reduced in c-SLE. Further analysis of patients revealed a negative correlation between LV peak longitudinal systolic strain and SLEDAI-2K(r= -0.52, p < 0.0001) and also between LV PLSS and the number of CRFs per patient (r = -0.32, p = 0.024). Conclusions: 2DST echocardiography has identified subclinical LV deformation impairment in c-SLE patients. Disease activity and cumulative exposure to CRFs contribute to myocardial compromise

INTRODUÇÃO: O acesso cirúrgico ao corno temporal do ventrículo lateral (CTVL) é realizado para tratamento de lesões temporais mediais, dentre as quais se destaca a esclerose hipocampal que leva à epilepsia, e pode ser realizado através das superfícies lateral ou inferior do lobo temporal ou pelo sulco lateral do cérebro (fissura silviana). O parênquima cerebral subcortical localizado entre o sulco limitante inferior da ínsula (SLI) e o CTVL é composto por importantes feixes de fibras brancas, os quais podem eventualmente ser lesionados nos acessos cirúrgicos trans-silvianos. OBJETIVO: Descrever a localização dos principais feixes de fibras brancas na região entre o SLI e o CTVL. MÉTODOS: Os principais feixes de fibras brancas subcorticais foram examinados em 14 hemisférios cerebrais cadavéricos adultos utilizando a técnica de dissecção de Klingler, sendo possível descrever suas posições em relação à extremidade anterior do SLI (nomeado de Ponto Temporal do Límen - PTL). RESULTADOS: Os principais feixes de fibras identificados profundamente ao SLI formam um arranjo multilaminar e podem ser divididos de acordo com a profundidade em que são encontrados. As fibras de associação curta da cápsula extrema, que continuam em direção aos opérculos, formam a camada subcortical mais superficial e foram encontradas sob todo o SLI. As fibras da cápsula externa são encontradas mais profundamente, em uma camada formada por três principais feixes em uma disposição anteroposterior sequencial: o fascículo uncinado (encontrado desde o PTL até 10,0 ± 2.2 mm posteriormente), o fascículo fronto-occipital inferior (encontrado entre 10,0 ± 2,2 mm e 35,5 ± 2,7 mm posterior ao PTL) e fibras claustro-corticais (encontradas desde 35,5 ± 2,7 mm posterior ao PTL até o final desse sulco). A extensão lateral da comissura anterior está logo abaixo dessa camada e suas fibras foram encontradas entre 8,4 ± 1,8 mm e 22,0 ± 6,8 mm posterior ao PTL. A camada mais profunda é formada pelas fibras da cápsula interna/corona radiata, onde se destacam as radiações ópticas cujas fibras foram encontradas entre 10,6 ± 3,4 mm e 34,5 ± 3,5 mm posterior ao PTL. CONCLUSÕES: O fascículo uncinado é aproximadamente encontrado sob o terço anterior do segmento anterior do SLI (entre o PTL e o corpo geniculado lateral), enquanto o fascículo fronto-occipital inferior e as fibras da radiação óptica são encontrados sob os dois terços posteriores deste segmento. Os resultados sugerem que na abordagem trans-silviana transinsular, uma incisão através do SLI, começando no PTL e se estendendo até 6 mm posteriormente, irá atravessar o fascículo uncinado, mas não o fascículo fronto-occipital inferior e as radiações ópticas / INTRODUCTION: The surgical approach to the temporal horn of the lateral ventricle (CTVL) is performed for treatment of medial temporal lesions, among which hippocampal sclerosis leading to epilepsy is emphasized, and can be performed through the lateral or inferior surfaces of the temporal lobe or through the sylvian fissure. The subcortical cerebral parenchyma located between the inferior limiting sulcus of the insula (SLI) and the CTVL is composed of important white matter fiber bundles, which may eventually be injured in transsylvian surgical approaches. OBJECTIVES: To describe the location of the main white matter fiber bundles in the region between SLI and CTVL. METHODS: The main subcortical white matter fiber bundles were examined in 14 adult cadaveric cerebral hemispheres using the Klingler dissection technique, and it was possible to describe their positions in relation to the anterior end of the SLI (named Temporal Limen Point - PTL). RESULTS: The main white matter fiber bundles identified deeply to the SLI form a multi-laminar arrangement that can be understood according to the depth in which they are found. The short association fibers of the extreme capsule, which continue toward the opercula, form the most superficial subcortical layer and were found underneath all the SLI. The external capsule fibers were found more deeply, in a layer formed by three main fiber bundles organized in a sequential anterior-posterior disposition: the uncinate fascicle (found from the PTL to 10.0 ± 2.2 mm posteriorly), the inferior fronto-occipital fascicle (found between 10.0 ± 2.2 mm and 35.5 ± 2.7 mm posterior to the PTL) and claustrocortical fibers (found from 35.5 ± 2.7 mm posterior to PTL to the end of this sulcus). The lateral extension of the anterior commissure was below this layer and its fibers were found between 8.4 ± 1.8 mm and 22.0 ± 6.8 mm posterior to the PTL. The deepest layer is formed by the fibers of the internal capsule/corona radiata, where the optical radiation fibers were distinguished and found between 10.6 ± 3.4 mm and 34.5 ± 3.5 mm posterior to the PTL. CONCLUSIONS: The uncinate fascicle is approximately found under the anterior third of the anterior SLI segment (between the PTL and the lateral geniculate body), while the inferior fronto-occipital fascicle and fibers of the optical radiation are found under the posterior two thirds of this segment. The results suggest that at the transsylvian-transinsular approach, an incision at the SLI, from the PTL to 6 mm posteriorly, will cross the uncinate fascicle, but not the inferior fronto-occipital fascicle and optical radiation fibers

Cardiac remodeling after acute myocardial infarction (MI) is an important process that leads to progressive ventricular enlargement and heart failure. Several variables have been identified to predict an increase in left ventricular (LV) volume and a decrease of LV ejection fraction (LVEF) after an acute MI including infarct size, anterior location, cardiac enzyme level, transmurality of the infarct, patency of the infarct-related artery, end systolic volume (ESV) and mitral deceleration time, etc. / Regional disturbances of LV wall motion have long been recognized to occur in patients with cardiac diseases, such as hypertrophic cardiomyopathy, unstable angina, acute ischemia, and MI. Tissue Doppler imaging (TDI) is recently established for detecting regional contractile abnormalities and asynchrony, and can predict reverse remodeling and improved synchronicity after biventricular pacing therapy in heart failure patients. However, it is unclear whether LV asynchrony plays an important role in the evolutionary changes of LV remodeling after an acute infarction and whether it can predict the changes independently. / The identification of transmural extent of myocardial necrosis and degree of non-viability after acute MI is clinically important. TDI-derived strain rate imaging (SRI) quantifies local rate of myocardial deformation and has the potential to differentiate viable from infarcted myocardium. / Therefore, in this study we aimed to investigate: (1) Whether SRI may differentiate transmural from non-transmural MI as assessed by ce-MRI in routine patients post acute infarction, and establish practical cutoff values for identifying transmural scar tissue from non-transmural or subendocardial infarction with viable myocardium. (2) Whether LV systolic and diastolic asynchrony measured by TDI occurs early after acute MI even in the absence of widening of QRS complexes, and determine if this is explained by the site and extent of the infarction measured by ce-MRI. (3) The relationships between serial measurements of infarct size on ce-MRI and LV remodeling process after an acute infarction, and determine whether early assessment of infarct size predicts progressive ventricular enlargement and cardiac dysfunction, and whether it differs with infarct location. (4) The relationships between LV asynchrony, infarct size and LV remodeling, and determine whether early assessment of LV asynchrony by TDI compared with standard clinical correlates of LV remodeling and infarct size predicts progressive ventricular enlargement and cardiac dysfunction. (Abstract shortened by UMI.) / Zhang Yan. / "April 2005." / Adviser: John E. Sanderson. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0175. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 161-192). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.