Ultrassonografia (US) é usada por médicos para ajudar em diagnósticos e intervenções. Ela fornece uma visada tomográfica de órgãos internos como, por exemplo, pâncreas aorta, fígado, bexiga, rins e baço. O médico pode utilizar a US para realizar apenas uma avaliação visual ou pode também comprimir o tecido para analisar a dinâmica, uma vez que a elasticidade da lesão pode estar relacionada à patologias. Consequentemente, diversos procedimentos computacionais vem sendo desenvolvidos com o intuito de fornecer ao médico informações acerca das propriedades elásticas do tecido. Entretanto, uma avaliação completa e objetiva dos procedimentos computacionais sobre US pode ser dificultada pelo difícil acesso a imagens com as propriedades desejadas ou pela falta de padrão-ouro para ser utilizado como referência. Portanto, nós desenvolvemos uma ferramenta capaz de criar phantoms numérico que imitam a compressão induzida por um médico através de um transdutor. A deformação do tecido é baseada em método doe elementos finitos e o deslocamento dos espalhadores é calculado usando isomorfismo linear. Depois do deslocamento dos espalhadores, Field II foi utilizado para simular o ruído Speckle. Assim, foi possível a criação de uma sequência de imagens de US com deformação realística. Este método foi implementado em Matlab e está disponível para download sem custos. A deformação do phantom foi validada através da medição de contraste de compressão em phantoms de duas camadas. Uma atenção especial foi dada a doenças cardiovasculares devido ao impacto que essas patologias causam no cenário médico do Brasil e do mundo. Nas últimas décadas, a prevalência de patologias cardiovasculares têm crescido progressivamente e se tornou uma séria questão de saúde pública. Elas estão entre as maiores causas de mortes, internações e gastos com saúde. Na prática intervencionista, o ultrassom intravascular (IVUS) é utilizado para obter informações do vaso sanguíneo e de eventuais patologias. Portanto, foi desenvolvida também uma simulação numérica de phantoms de IVUS. A simulação do vaso sanguíneo também se baseou em método dos elementos finitos e isomorfismo linear. Contudo, uma simulação confiável de IVUS deve considerar o caminho do cateter no interior do vaso sanguíneo, porque isto determina a posição do transdutor. Portanto, nós desenvolvemos um novo método, baseado em equilíbrio de forças, para determinar a posição de menor energia do cateter. O método foi validado através da comparação da posição estimada com a posição de um fio-guia de aço real e apresentou erro quadrático médio e média Hausdorff menor que 1 mm para ambos. Foram utilizados dois métodos diferentes para rastrear e estimar a deformação de determinadas estruturas no tecido: Optical Flow e 2D Block Matching. Foi aplicado uma implementação inovadora de 2D Block Matching com interpolação sub-pixel linear e propagação de deslocamento. Posteriormente, a validação será feita comparando-se a o movimento estimado com o padrão-ouro numérico utilizado para construir a simulação. O 2D block matching forneceu resultados melhores que o optical flow. Após a análise em phantoms numéricos, equipamento real de ultrassom foi utilizado para aquisição de imagens modo-B de phantoms físicos. Então, nós realizamos a estimativa do movimento das estruturas para analisar as propriedades morfológicas e dinâmicas do tecidos. Os resultados obtidos foram comparados com a elastografia fornecida pelo equipamento. Em acordo com os resultados obtidos na simulação numérica, o 2D block matching novamente apresentou resultados melhores que o optical flow. Finalmente, os dois métodos de rastreamento foi aplicada em imagens simuladas de IVUS, que foram divididas em 2 conjuntos de quadros. O primeiro conjunto, S1, continha todos os quadros da sequência de IVUS e o segundo conjunto, S2, continha apenas os quadros correspondentes a uma fase específica do ciclo cardíaco. Sendo assim, foi analisado o balanço entre o impacto do movimento cardíaco e a taxa de quadros. Para os pontos localizados nas bordas dos objetos, Optical flow teve um bom desempenho para ambos S1 e S2. Em regiões homogêneas, entretanto, o optical flow foi capaz de rastrear os pontos em S2, sugerindo que é melhor o trabalho com movimento cardíaco reduzido em detrimento da taxa de quadros, tal qual a aquisição de IVUS engatilhado por ECG. Já o 2D block matching apresentou um mau rastreamento para todos os pontos selecionados. Além da simulação da aquisição de ultrassonografia com deformação e do rastreamento de estruturas, também desenvolvemos uma nova técnica de filtragem capaz de remover a textura speckle sem borrar as bordas. A técnica proposta apresentou os melhores resultados quando comparados com outros nove filtros da literatura. Foi desenvolvida também uma nova métrica que utiliza o ruído speckle da própria imagem para fornecer um parâmetro que pode ajudar o usuário a decidir o tamanho da janelo de um filtro. / Ultrasonography (US) is used by physicians to help on diagnosis and interventions. It provides tomographic views of inner organs such as pancreas, aorta, inferior vena cava, liver, gall bladder, bile ducts, kidneys and spleen. The physician may utilize US to perform only a visual assessment or may also compress the tissue to analyze its dynamics, since lesion elasticity may be related to dangerousness. Consequently, several computational procedures have been developed in order to provide information about the elastic properties of the tissue. However, a thorough and objective evaluation of US computational procedures may be hindered by the difficult access to US images with the desired features and the lack of gold-standard parameters. Therefore, we developed a tool that is able to create numeric phantom that mimics the compression induced by physician with the transducer. The tissue deformation was based on finite elements method and the displacement of the scatterers were calculated using linear isomorphism. After the scatterer displacement, Field II was used to simulate the speckle noise. Thus, it is possible to create a sequence of US images with realistic deformation. This technique was implemented in Matlab and is available for free download. The phantom deformation was validated by measuring the strain contrast from double-layered phantoms. Special attention was given to cardiovascular diseases due to their impact on Brazilian and world populations. During the last decades, the prevalence of cardiovascular pathologies has increased progressively, and has become a serious public health problem. They are among the major causes of death, hospitalizations and health expenses. In interventionist practice, intravascular ultrasound (IVUS) is used to obtain information about blood vessels and eventual pathologies. Therefore, we also created numeric IVUS phantoms. The simulation of the blood vessel was also based in finite elements method with linear isomorphism. However, a reliable IVUS simulation must consider the catheter path inside the blood vessel, because it determines the position of the transducer. Hence, we developed a new method, based on equilibrium of forces, to determine the minimum energy position of the catheter. The method was validated by comparing its position with the position of a real stainless steel IVUS guidewire and presented root mean squared error and Hausdorff mean smaller than 1 mm for both. We used two different techniques to track and estimate deformation of different structures in the simulated US images, namely, Optical Flow and 2D Block Matching. We applied an innovative implementation of 2D block matching with sub-pixel linear interpolation and displacement propagation. Then, the estimated deformation from both methods were compared with the numeric gold-standard, and 2D block matching presented better results than optical flow. After the work with numeric phantoms, real US equipment was utilized to acquire B-mode images from a physical phantom. Then, we performed the movement estimation of the imaged tissue to analyze its morphological and dynamic properties. The results were compared to the elastography images provided by the US equipment. In accordance with the results from the numeric simulation, 2D block matching presented better results than Optical flow. Finally, we performed the two speckle tracking on a set of numerically simulated IVUS images, where the images were divided into two sets of frames. The first set, S1, contained all the frames from the IVUS sequence and the second set, S2, contained only the frames corresponding to a specific phase of the cardiac cycle. Thus, we analyzed the trade-off between the impact of the cardiac motion and low frame rate. For the points located at the edges of the object, optical flow had a good performance for both S1 and S2. In homogenous regions, however, optical flow was able to track the points only in S2, suggesting that it is better to work with low frame rate and reduced cardiac motion, as in EKG-triggered IVUS acquisition. 2D block matching presented poor results in all points of both S1 and S2. Besides the simulation of ultrasound acquisition with deformation and structure tracking, in this work, we also developed a new filtering technique that is able to remove the speckle texture without blurring the edges. The proposed filter presented the best results when compared to other nine filters from the literature. We also developed a metric that uses the speckle texture of the image to provide a parameter that may help the user decide the size of the window of the filter.

Ultrassonografia (US) é usada por médicos para ajudar em diagnósticos e intervenções. Ela fornece uma visada tomográfica de órgãos internos como, por exemplo, pâncreas aorta, fígado, bexiga, rins e baço. O médico pode utilizar a US para realizar apenas uma avaliação visual ou pode também comprimir o tecido para analisar a dinâmica, uma vez que a elasticidade da lesão pode estar relacionada à patologias. Consequentemente, diversos procedimentos computacionais vem sendo desenvolvidos com o intuito de fornecer ao médico informações acerca das propriedades elásticas do tecido. Entretanto, uma avaliação completa e objetiva dos procedimentos computacionais sobre US pode ser dificultada pelo difícil acesso a imagens com as propriedades desejadas ou pela falta de padrão-ouro para ser utilizado como referência. Portanto, nós desenvolvemos uma ferramenta capaz de criar phantoms numérico que imitam a compressão induzida por um médico através de um transdutor. A deformação do tecido é baseada em método doe elementos finitos e o deslocamento dos espalhadores é calculado usando isomorfismo linear. Depois do deslocamento dos espalhadores, Field II foi utilizado para simular o ruído Speckle. Assim, foi possível a criação de uma sequência de imagens de US com deformação realística. Este método foi implementado em Matlab e está disponível para download sem custos. A deformação do phantom foi validada através da medição de contraste de compressão em phantoms de duas camadas. Uma atenção especial foi dada a doenças cardiovasculares devido ao impacto que essas patologias causam no cenário médico do Brasil e do mundo. Nas últimas décadas, a prevalência de patologias cardiovasculares têm crescido progressivamente e se tornou uma séria questão de saúde pública. Elas estão entre as maiores causas de mortes, internações e gastos com saúde. Na prática intervencionista, o ultrassom intravascular (IVUS) é utilizado para obter informações do vaso sanguíneo e de eventuais patologias. Portanto, foi desenvolvida também uma simulação numérica de phantoms de IVUS. A simulação do vaso sanguíneo também se baseou em método dos elementos finitos e isomorfismo linear. Contudo, uma simulação confiável de IVUS deve considerar o caminho do cateter no interior do vaso sanguíneo, porque isto determina a posição do transdutor. Portanto, nós desenvolvemos um novo método, baseado em equilíbrio de forças, para determinar a posição de menor energia do cateter. O método foi validado através da comparação da posição estimada com a posição de um fio-guia de aço real e apresentou erro quadrático médio e média Hausdorff menor que 1 mm para ambos. Foram utilizados dois métodos diferentes para rastrear e estimar a deformação de determinadas estruturas no tecido: Optical Flow e 2D Block Matching. Foi aplicado uma implementação inovadora de 2D Block Matching com interpolação sub-pixel linear e propagação de deslocamento. Posteriormente, a validação será feita comparando-se a o movimento estimado com o padrão-ouro numérico utilizado para construir a simulação. O 2D block matching forneceu resultados melhores que o optical flow. Após a análise em phantoms numéricos, equipamento real de ultrassom foi utilizado para aquisição de imagens modo-B de phantoms físicos. Então, nós realizamos a estimativa do movimento das estruturas para analisar as propriedades morfológicas e dinâmicas do tecidos. Os resultados obtidos foram comparados com a elastografia fornecida pelo equipamento. Em acordo com os resultados obtidos na simulação numérica, o 2D block matching novamente apresentou resultados melhores que o optical flow. Finalmente, os dois métodos de rastreamento foi aplicada em imagens simuladas de IVUS, que foram divididas em 2 conjuntos de quadros. O primeiro conjunto, S1, continha todos os quadros da sequência de IVUS e o segundo conjunto, S2, continha apenas os quadros correspondentes a uma fase específica do ciclo cardíaco. Sendo assim, foi analisado o balanço entre o impacto do movimento cardíaco e a taxa de quadros. Para os pontos localizados nas bordas dos objetos, Optical flow teve um bom desempenho para ambos S1 e S2. Em regiões homogêneas, entretanto, o optical flow foi capaz de rastrear os pontos em S2, sugerindo que é melhor o trabalho com movimento cardíaco reduzido em detrimento da taxa de quadros, tal qual a aquisição de IVUS engatilhado por ECG. Já o 2D block matching apresentou um mau rastreamento para todos os pontos selecionados. Além da simulação da aquisição de ultrassonografia com deformação e do rastreamento de estruturas, também desenvolvemos uma nova técnica de filtragem capaz de remover a textura speckle sem borrar as bordas. A técnica proposta apresentou os melhores resultados quando comparados com outros nove filtros da literatura. Foi desenvolvida também uma nova métrica que utiliza o ruído speckle da própria imagem para fornecer um parâmetro que pode ajudar o usuário a decidir o tamanho da janelo de um filtro. / Ultrasonography (US) is used by physicians to help on diagnosis and interventions. It provides tomographic views of inner organs such as pancreas, aorta, inferior vena cava, liver, gall bladder, bile ducts, kidneys and spleen. The physician may utilize US to perform only a visual assessment or may also compress the tissue to analyze its dynamics, since lesion elasticity may be related to dangerousness. Consequently, several computational procedures have been developed in order to provide information about the elastic properties of the tissue. However, a thorough and objective evaluation of US computational procedures may be hindered by the difficult access to US images with the desired features and the lack of gold-standard parameters. Therefore, we developed a tool that is able to create numeric phantom that mimics the compression induced by physician with the transducer. The tissue deformation was based on finite elements method and the displacement of the scatterers were calculated using linear isomorphism. After the scatterer displacement, Field II was used to simulate the speckle noise. Thus, it is possible to create a sequence of US images with realistic deformation. This technique was implemented in Matlab and is available for free download. The phantom deformation was validated by measuring the strain contrast from double-layered phantoms. Special attention was given to cardiovascular diseases due to their impact on Brazilian and world populations. During the last decades, the prevalence of cardiovascular pathologies has increased progressively, and has become a serious public health problem. They are among the major causes of death, hospitalizations and health expenses. In interventionist practice, intravascular ultrasound (IVUS) is used to obtain information about blood vessels and eventual pathologies. Therefore, we also created numeric IVUS phantoms. The simulation of the blood vessel was also based in finite elements method with linear isomorphism. However, a reliable IVUS simulation must consider the catheter path inside the blood vessel, because it determines the position of the transducer. Hence, we developed a new method, based on equilibrium of forces, to determine the minimum energy position of the catheter. The method was validated by comparing its position with the position of a real stainless steel IVUS guidewire and presented root mean squared error and Hausdorff mean smaller than 1 mm for both. We used two different techniques to track and estimate deformation of different structures in the simulated US images, namely, Optical Flow and 2D Block Matching. We applied an innovative implementation of 2D block matching with sub-pixel linear interpolation and displacement propagation. Then, the estimated deformation from both methods were compared with the numeric gold-standard, and 2D block matching presented better results than optical flow. After the work with numeric phantoms, real US equipment was utilized to acquire B-mode images from a physical phantom. Then, we performed the movement estimation of the imaged tissue to analyze its morphological and dynamic properties. The results were compared to the elastography images provided by the US equipment. In accordance with the results from the numeric simulation, 2D block matching presented better results than Optical flow. Finally, we performed the two speckle tracking on a set of numerically simulated IVUS images, where the images were divided into two sets of frames. The first set, S1, contained all the frames from the IVUS sequence and the second set, S2, contained only the frames corresponding to a specific phase of the cardiac cycle. Thus, we analyzed the trade-off between the impact of the cardiac motion and low frame rate. For the points located at the edges of the object, optical flow had a good performance for both S1 and S2. In homogenous regions, however, optical flow was able to track the points only in S2, suggesting that it is better to work with low frame rate and reduced cardiac motion, as in EKG-triggered IVUS acquisition. 2D block matching presented poor results in all points of both S1 and S2. Besides the simulation of ultrasound acquisition with deformation and structure tracking, in this work, we also developed a new filtering technique that is able to remove the speckle texture without blurring the edges. The proposed filter presented the best results when compared to other nine filters from the literature. We also developed a metric that uses the speckle texture of the image to provide a parameter that may help the user decide the size of the window of the filter.

Rupture of atherosclerotic plaque is closely related to plaque composition. Currently, plaque composition cannot be clinically characterized by any imaging modality. The objective of this dissertation is to use a recently developed imaging modality – ultrasound-guided intravascular photoacoustic (IVPA) imaging – to detect the distribution of two critical components in atherosclerotic plaques: lipid and phagocytically active macrophages. Under the guidance of intravascular ultrasound imaging, spectroscopic IVPA imaging is capable of detecting the spatially resolving optical absorption property inside a vessel wall. In this study, contrast in spectroscopic IVPA imaging was provided by either the endogenous optical property of lipid or optically absorbing contrast agent such as gold nanoparticles (Au NPs). Using a rabbit model of atherosclerosis, this dissertation demonstrated that ultrasound guided spectroscopic IVPA imaging could simultaneously image lipid deposits as well as macrophages labeled in vivo with Au NPs. Information of macrophage activity around lipid rich plaques may help to identify rupture-prone or vulnerable plaques. The results show that ultrasound guided IVPA imaging is promising for detecting plaque composition in vivo. Clinical use of ultrasound guided IVPA imaging may significantly improve the accuracy of diagnosis and lead to more effective treatments of atherosclerosis. / text

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / DoenÃas infecciosas constituem a principal causa de morte em todo o mundo. Dentre estas, as causadas por infecÃÃes bacterianas se destacam devido à diversidade de bactÃrias e à sua capacidade evolutiva e adaptativa. Respostas inflamatÃrias inadequadas estÃo associadas a essas infecÃÃes e em detrimento de avanÃos cientÃficos, o diagnÃstico precoce e o tratamento de quadros de infecÃÃes bacterianas sistÃmicas permanecem um desafio à saÃde pÃblica. Neste contexto, este estudo avaliou a capacidade da lectina de Canavalia brasiliensis (ConBr) e Cratylia argentea (CFL) em modular a inflamaÃÃo sistÃmica causada por Salmonella enterica sorotipo Typhimurium. As lectinas foram purificadas por cromatografia de afinidade em coluna de Sephadex G-50 e ensaios de avaliaÃÃo toxicolÃgica e seguranÃa farmacolÃgica foram realizados. Ambas as lectinas nÃo demonstraram toxicidade atà a mÃxima dose de 2000 mg/kg. EntÃo, camundongos foram inoculados, por via intraperitoneal, com as lectinas (10 mg/kg), 72, 48 e 24 horas antes de serem infectados com a Salmonella (107 UFC/mL). Foi observada uma sobrevida de 100% e 90% dos animais tratados com a ConBr e CFL, respectivamente, avaliados no sÃtimo dia. Este protocolo reduziu significativamente o nÃmero de bactÃrias no sangue, fluÃdo peritoneal e nos principais ÃrgÃos da infecÃÃo (baÃo e fÃgado). Foi observado ainda reversÃo da falÃncia na migraÃÃo de neutrÃfilos, leucopenia, bem como, reduÃÃo nos nÃveis de citocinas (TNF-α, IL-1 e IL-10) e Ãxido nÃtrico no soro. Foi tambÃm verificado um aumento na concentraÃÃo de Ãxido nÃtrico no fluido peritoneal e do nÃmero de plaquetas no sangue. AnÃlises in vitro mostraram que ambas as lectinas nÃo apresentam atividade bactericida, reduzem o tempo de ativaÃÃo do sistema complemento e aumentam o tempo de coagulaÃÃo intrÃnseca e extrÃnseca. As lectinas nÃo apresentaram efeito curativo quando administradas apÃs a infecÃÃo e nÃo demonstraram efeito preventivo quando inoculadas por via endovenosa ou oral. AtravÃs da anÃlise proteÃmica, proteÃnas relacionadas à infecÃÃo e à aÃÃo moduladora das lectinas foram identificadas. Assim, as lectinas possivelmente atuam sobre os macrÃfagos/monÃcitos, controlando sua ativaÃÃo, e desta forma, atenuando o processo inflamatÃrio e protegendo os animais do choque sÃptico. Estes resultados representam uma interessante perspectiva para o controle de infecÃÃes, com uso independente ou associado a antibiÃticos de aÃÃo direta sobre microrganismos / Infectious diseases are a leading cause of death throughout the world. Among these, bacterial infections stand out due to the enormous diversity of bacteria and their evolutionary and adaptive abilities. Inappropriate inflammatory responses have been associated with these infections and despite contemporaneous scientific approaches, timely diagnosis and proper treatment of systemic bacterial infection are still a challenge for public health. Thus, this study evaluated the ability of Canavalia brasiliensis (ConBr) and Cratylia argentea (CFL) lectin in modulating systemic inflammation caused by Salmonella enterica serovar Typhimurium. The lectins were purified by affinity chromatography on Sephadex G50. Toxicology and the pharmacological security of lectins was evaluated. Both lectins exhibited no toxicity up to 2000 mg/kg. Mice were inoculated intraperitoneally with lectins (10 mg/kg) within 72, 48 and 24 h before infection with Salmonella (107 CFU/mL). Animals treated with ConBr and CFL, respectively, showed 100% and 90% survival, seven days after infection. This protocol significantly reduced the bacteria in blood, peritoneal fluid and in main organs such as liver and spleen. It was also observed a reversal of the neutrophil migration failure, leukopenia, as well as reduction of cytokine levels (TNF- α, IL- 1 and IL -10) and nitric oxide on the serum. In addition, elevated peritoneal fluid concentration of nitric oxide and increase in the number of platelets were found. In vitro analyzes identified that both lectins did not exhibit antibacterial activity, can decrease the time of activation of complement system and increase intrinsic and extrinsic clotting time. Lectins had no curative effect when administered after infection and none protective effect when inoculated either intravenously or orally. Through proteomic analysis, proteins related to infection and to modulating action of lectins were identified. According to our results, we found that lectins can act on macrophages/monocytes, controlling their activation and thereby influencing the inflammatory process, protecting the animals from septic shock. These results represent an interesting approach for the control of infections, using lectins independently or associated with antibiotics whose action is directly on microorganisms.

Orientador: Marcia Ferreira da Rosa Sobreira / Resumo: Alterações hemostáticas são anormalidades suspeitadas em equinos com obstruções intestinais, estando associadas a elevadas taxas de morbidade e mortalidade. Contudo, as técnicas e/ou testes usados rotineiramente para avaliar a hemostasia apresentam grandes limitações, pois avaliam fases ou componentes isolados do processo hemostático. Em contraste, a tromboelastografia é uma técnica atual que avalia a dinâmica do processo de coagulação sanguínea em conjunto, tornando possível a obtenção de informações acuradas. Como estudos recentes relataram que o uso de plasma fresco ou congelado estaria apresentado resultados satisfatórios tanto em seres humanos como em animais, o presente estudo teve como objetivo inicial realizar testes hemostáticos convencionais (TP, TTPA, Fibrinogênio) e viscoelásticas (tromboelastografia) do plasma de 20 equinos hígidos, 20 equinos com obstrução simples (compactação de colo) e de 20 com obstrução estrangulativa (vólvulo) de alças intestinais de ocorrência natural. Na interpretação dos resultados, verificou-se que o uso da Análise por Componentes Principais foi efetiva na caracterização dos indíviduos a partir dos resultados dos testes realizados. Ademais, ao transformar a interação entre os componentes do processo hemostático em uma visualização gráfica, a tromboelastografia possibilitou uma interpretação e entendimento efetivos do que está acontecendo na coagulação do indivíduo. Assim sendo, pode-se concluir que os testes por métodos convencionais e ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Haemostatic changes are suspected abnormalities in horses with intestinal obstructions, being associated with high rates of morbidity and mortality. However, the techniques and / or tests routinely used to evaluate hemostasis have major limitations, since they evaluate isolated phases or components of the hemostatic process. In contrast, thromboelastography is a current technique that evaluates the dynamics of the blood coagulation process together, making it possible to obtain accurate information. As recent studies have reported that the use of fresh or frozen plasma would present satisfactory results in both humans and animals, the present study aimed to perform conventional hemostatic (PT, APTT, Fibrinogen) and viscoelastic (thromboelastography) plasma analyzes of 20 healthy equines, 20 equines with simple obstruction (colon impactation), and 20 with strangulative obstruction (volvulus) of naturally occurring intestinal loops. In the interpretation of the results, it was verified that the use of Principal Component Analysis was effective in the characterization of the individuals from the results of the tests performed. In addition, by transforming the interaction between the components of the hemostatic process in a graphical view, thromboelastography enabled an effective interpretation and understanding of what is happening in the coagulation of the individual. Thus, it can be concluded that tests by conventional methods and the viscoelastic evaluation of citrated plasm... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2016-01-26T12:51:10Z (GMT). No. of bitstreams: 1 fransciscoricardomarqueslobo_tese.pdf: 196880 bytes, checksum: f40e2b740711953b1294f3b6b0e252f2 (MD5) Previous issue date: 2007-01-23 / Disseminated intravascular coagulation (DIC) is a syndrome caused by systemic activation of clotting factors and it is frequently associated with several diseases such as sepsis, trauma, shock, cancer, and immune and vascular disorders. Sepsis is the main clinical condition associated to DIC. In some cases, the clinical outcome is very fast and severe, and an early management establishes a better outcome. Using a score suggested by the International Society of Thrombosis and Haemostasis to perform a DIC diagnosis, we were able to evaluate the frequency of its occurrence in patients admitted to the intensive care unit. The serum concentrations of coagulation and fibrinolysis markers within the first 72 hours of admission and the role of these markers as early predictors in the development of DIC were retrospectively estimated. Fifty clinical and surgical patients presenting sepsis, shock, and multiple traumas were included in the study. Of the 50 patients examined, 10 (20%) developed DIC within the first 48 hours of ICU admission. The logistic regression analysis showed that the decreased antithrombin level (p = 0.0355) on admission are predictive of DIC development. This result may have a relevant involvement in clinical outcome because the early intervention can change the DIC prognosis. / A Coagulação intravascular disseminada (CIVD) é uma síndrome causada por ativação sistêmica da coagulação e freqüentemente associada com diversas doenças como sepse, trauma, choque, câncer e anormalidades imunológicas e vasculares. A sepse é a principal condição clínica associada à CIVD. Em alguns casos, a evolução clínica é muito rápida e grave e o tratamento precoce determina melhor evolução. Com o uso do escore para diagnóstico de CIVD proposto pela Sociedade Internacional de Trombose e Hemostasia avaliamos a freqüência de ocorrências de CIVD em pacientes admitidos em unidade de terapia intensiva. As concentrações séricas dos marcadores da coagulação e fibrinólise nas primeiras 72 horas da internação e o papel desses marcadores como preditores precoces do desenvolvimento de CIVD foram avaliados retrospectivamente. Cinqüenta pacientes (clínicos e cirúrgicos) apresentando sepse, choque e politrauma foram incluídos no estudo. Dos 50 pacientes avaliados, 10 pacientes (20%) desenvolveram CIVD durante as primeiras 48 horas de internação na UTI. A análise por regressão logística mostrou que o nível diminuído de antitrombina (p= 0,0355) na admissão é preditivo do desenvolvimento de CIVD. Esse resultado pode ter implicação relevante na evolução clínica, pois a intervenção precoce poderá mudar o prognóstico da CIVD.

Coronary artery disease is a leading cause of death in the Western world. Symptoms present only late in the progression of the disease, limiting treatment options; moreover, the inability to biopsy arterial tissue in a living patient makes it difficult to study the pathology effectively. 89 patients were imaged twice at a one year interval using x-ray angiography (the traditional modality for assessment of arterial stenosis) and intravascular ultrasound (IVUS), which yields a detailed image of the structure of the vessel wall. 32 of these 89 patients were made available for analysis in this study. The Volcano Corp.~IVUS acquisition systems include software that provides a \textit{virtual histology} (VH) characterization of plaque composition that provides information otherwise only available by biopsy. Using a geometric reconstruction method described in previous work, a full working model of wall shear stresses (WSS) produced by blood flow and vessel wall composition is created. Using these, the morphologic structural information gleaned from the 3-D reconstruction, and some additional composite indices, combined with demographic information collected at enrollment and serum biomarkers collected from each patient during imaging, a detailed portrait of each patient's disease state is created, with the objective of predicting disease evolution over a 1 year timescale. We have, in the course of this study, accomplished the following 5 aims towards the goal of predicting localized changes in disease state on a 1 year timescale: Aim 1: Develop and validate a method of compensating for rotational motion of the catheter within the vessel and its effect upon the 3-D orientation of the reconstruction. Aim 2: Develop and validate a method of registering the reconstructed vessels that permits identification of a point-to-point correspondence on all quantitative indices. Aim 3: Successfully reconstruct, register, and analyze image sets for each of as many patients as possible for analysis. Aim 4: Identify statistically significant indices in the data suitable for use as features in a classifier. Aim 5: Construct and assess performance of a classification system that can draw useful conclusions about the 1-year progression of the arterial pathology in a patient not used in the training set. Aim 2 was a complete success. Branches were reliably present in the IVUS data in sufficient quantities to facilitate reliable identification of the overlap and the requisite spatial transformation required to map points from one pullback onto another. Aim 1 was much more problematic. While a method was developed which showed promise, the image acquisition protocol did not provide for orientation of the angiograms with an eye towards bifurcation identification. With neither an analytic model, nor reasonable fiducials, the method developed could only be tested on a small subset of the data, limiting both our confidence in its validation, as well as its usability in this study. It is hoped that the method can be refined and used in any subsequent study, given proper planning during the acquisition of the images, and that in turn the spatial reliability of the reconstructions can be improved beyond what is possible today. Regarding aim 3, 32 patients were ultimately processed completely. Aims 4 and 5 were completed successfully. Meaningful correlations were identified in the data, and the results illustrate that while we were by no means able to obtain perfect classification, we were able to handily beat a both a random, and a maximum likelihood classifier.

<p>with biliary cirrhosis are highly susceptible to acute pulmonary dysfunction and suffer from hepato-pulmonary syndrome. The mechanisms of this enhanced susceptibility remain unknown. It is well established that pulmonary intravascular macrophages (PIMs) are present in cattle, horses, goat and sheep and increase susceptibility for lung inflammation. Species such as rat and mouse also recruit PIMs especially in a bile duct ligation model of biliary cirrhosis. The contributions of recruited PIMs to lung inflammation associated with liver dysfunction remain unknown. Therefore, I characterized a bile duct ligation (BDL) model in rats to study role of recruited PIMs in lung inflammation. First, Sprague Dawley rats were subjected to BDL (N=6) or sham surgeries (N=3) and were euthanized at 4 weeks post-surgery. Five rats were used as the controls. Lung tissues were collected and processed for histology, immunohistology, immuno-electron microscopy, enzyme-linked immunosorbant assay (ELISA) and reverse transcriptase-polymerase chain reaction (RT-PCR). Light microscopy demonstrated normal lung morphology in sham-operated and control rats but showed septal recruitment of mononuclear cells, which were positive for anti-rat monocytes/macrophage antibody ED-1, in BDL rats (p=0.002). Immuno-electron microscopy confirmed localization of ED-1 in PIMs. BDL rats showed increased lung expression of monocyte chemoattractant protein-1 (MCP-1) protein and mRNA compared to the controls (p=0.017) but not of IL-1â, TNF-á, TGF-â and IL-10. Then, I treated BDL rats (N=5) with gadolinium chloride (GC; 10 mg/Kg body weight intravenous) and found reduced numbers of PIMs (p=0.061) at 48 hours post-treatment along with increased expression of TGF-â and IL-10.</p><p>I challenged control rats (N=5) and BDL rats (N=6) with Escherichia coli lipopolysaccharide (E. coli LPS; 0.1 mg/Kg body weight intravenous). All the BDL rats died within 3 hours of LPS challenge (100% mortality) while the normal LPS-treated rats were euthanized at 6 hours post-treatment. Histology and ED-1 staining showed dramatic increase in the number of septal monocytes/macrophages in BDL+LPS rats compared to normal LPS-treated rats (p=0.000). Staining of lung sections with an LPS antibody localized the LPS in lungs. RT-PCR analyses showed no differences in IL-1â transcript levels between LPS challenged BDL rats and LPS challenged control rats (p=0.746) but ELISA showed increase in IL-1â concentration in LPS challenged BDL rats compared to LPS challenged control rats (p=0.000). TNF-á mRNA (p=0.062) and protein (p=0.000) was increased in BDL+LPS rats compared to the control+LPS rats. Immuno-electron microscopy showed IL-1â and TNF-á in PIMs. BDL rats challenged with LPS showed increased expression of IL-10 mRNA and protein (p=0.000 & 0.002 respectively) in lungs compared to LPS challenged control rats. TGF-â mRNA did not change (p=0.128) but lower protein concentrations (p=0.000) were observed in LPS-treated control rats compared to BDL+LPS. </p><p> To further address the role of PIMs, I treated rats with GC at 6 hours or 48 hours (N=5 each) before LPS challenge. The mortality in the 6 hour group was 20% while all the rats in 48 hour group survived till 6 hours. Histology and ED-1 staining showed decrease in the number of intravascular cells in these groups compared to LPS treated BDL rats (p=0.039 for 6 hour group; p= 0.002 for 48 hour group). There were no differences in IL-1â mRNA in both 6 hour and 48 hour groups compared to the LPS challenged BDL rats (p=0.712 & 0.509 respectively). ELISA showed no decrease in IL-1â concentration in 6 hour GC-treated group but a decrease was noticed at 48 hours compared to LPS challenged BDL rats (p=0.455 & 0.008 respectively). TNF-á mRNA levels were not different between LPS-challenged GC-treated BDL rats and LPS-challenged BDL rats (p=0.499 & 0.297 for 6 hour & 48 hour GC groups respectively). But TNF-á concentration in 48 hour GC group (p=0.001) but not in 6 hour GC group (p=0.572) was lower in comparison to BDL+LPS group. IL-10 mRNA was decreased in both 6 hour and 48 hour GC groups (p=0.038 & 0.000 respectively) compared to LPS challenged BDL rats. ELISA showed decrease in IL-10 concentration in 48 hour GC group (p=0.030) but not in 6 hour GC group (p=0.420). TGF-â mRNA expression was decreased in 48 hour GC group (p=0.000) but not in 6 hour GC group (p=0.182). But GC treatment did not affect TGF-â concentrations. </p><p>The data from these experiments characterize a BDL model to study PIM biology, show PIMs pro-inflammatory potential and their possible role as a therapeutic target in lung inflammation.</p>

Les malalties cardiovasculars són una de les principals causes de mortalitat als països desenvolupats. La majoria d'elles són degudes a malalties arterials (especialment les coron ries), que vénen causades per l'acumulació de placa. Aquesta patologia estreny el flux sanguini (estenosi) i afecta les propietats elàstiques i bio-mecàniques (arteriosclerosi) de les artèries. En les últimes dècades, l'Ecografia Intra-Coronària (EIC) ha esdevingut una tècnica usual de diagnòstic per la imatge i seguiment de les malalties coronàries. L'EIC està basada en un cateterisme que mostra una seqüència d'imatges corresponents a seccions de l'artèria sota estudi. La inspecció visual de cadascuna d'aquestes imatges proporciona informació sobre el percentatge d'estenosi, mentre que la inspecció de les vistes longitudinals propociona informació sobre les propietats bio-mecàniques, que pot prevenir un desenllaç fatal de la malaltia cardiovascular. Per una banda, la dinàmica arterial (deguda al batec del cor, entre d'altres) és un dels principals artefactes per poder explorar les propietats biomecàniques. Al mateix temps, les mesures manuals d'estenosi requereixen un traçat manual de les vores del vas, tasca feixuga que consumeix molt de temps i que pot patir variabilitat entre observadors.Aquesta tesi proposa vàries eines de processament d'imatge per explorar la dinàmica de les artèries i les seves estructures. Presentem un model físic per extreure, analitzar i corregir la dinàmica rígida transversal dels vasos i per recuperar la fase cardíaca. A més, introduïm un mètode estadístic-determinista per a la detecció automàtica de les vores del vas. En particular, l'enfoquem a segmentar l'adventícia. Un protocol de validació acurat per assegurar una aplicació clínica fiable dels mètodes és un pas crucial en qualsevol proposta d'algorisme. En aquesta tesi tenim especial cura de dissenyar protocols de validació per a cadascuna de les tècniques proposades i contribuïmm a la validació de la dinàmica in vivo amb un indicador objectiu i quantitatiu per mesurar la quantitat de moviment suprimida. / Cardiovascular diseases are a leading cause of death in developed countries. Most of them are caused by arterial (specially coronary) diseases, mainly caused by plaque accumulation. Such pathology narrows blood flow (stenosis) and affects artery bio-mechanical elastic properties (atherosclerosis). In the last decades, IntraVascular UltraSound (IVUS) has become a usual imaging technique for the diagnosis and follow up of arterial diseases. IVUS is a catheter-based imaging technique which shows a sequence of cross sections of the artery under study. Inspection of a single image gives information about the percentage of stenosis. Meanwhile, inspection of longitudinal views provides information about artery bio-mechanical properties, which can prevent a fatal outcome of the cardiovascular disease. On one hand, dynamics of arteries (due to heart pumping among others) is a major artifact for exploring tissue bio-mechanical properties. On the other one, manual stenosis measurements require a manual tracing of vessel borders, which is a time-consuming task and might suffer from inter-observer variations.This PhD thesis proposes several image processing tools for exploring vessel dynamics and structures. We present a physics-based model to extract, analyze and correct vessel in-plane rigid dynamics and to retrieve cardiac phase. Furthermore, we introduce a deterministic-statistical method for automatic vessel borders detection. In particular, we address adventitia layer segmentation. An accurate validation protocol to ensure reliable clinical applicability of the methods is a crucial step in any proposal of an algorithm. In this thesis we take special care in designing a validation protocol for each approach proposed and we contribute to the in vivo dynamics validation with a quantitative and objective score to measure the amount of motion suppressed.

<p>with biliary cirrhosis are highly susceptible to acute pulmonary dysfunction and suffer from hepato-pulmonary syndrome. The mechanisms of this enhanced susceptibility remain unknown. It is well established that pulmonary intravascular macrophages (PIMs) are present in cattle, horses, goat and sheep and increase susceptibility for lung inflammation. Species such as rat and mouse also recruit PIMs especially in a bile duct ligation model of biliary cirrhosis. The contributions of recruited PIMs to lung inflammation associated with liver dysfunction remain unknown. Therefore, I characterized a bile duct ligation (BDL) model in rats to study role of recruited PIMs in lung inflammation. First, Sprague Dawley rats were subjected to BDL (N=6) or sham surgeries (N=3) and were euthanized at 4 weeks post-surgery. Five rats were used as the controls. Lung tissues were collected and processed for histology, immunohistology, immuno-electron microscopy, enzyme-linked immunosorbant assay (ELISA) and reverse transcriptase-polymerase chain reaction (RT-PCR). Light microscopy demonstrated normal lung morphology in sham-operated and control rats but showed septal recruitment of mononuclear cells, which were positive for anti-rat monocytes/macrophage antibody ED-1, in BDL rats (p=0.002). Immuno-electron microscopy confirmed localization of ED-1 in PIMs. BDL rats showed increased lung expression of monocyte chemoattractant protein-1 (MCP-1) protein and mRNA compared to the controls (p=0.017) but not of IL-1â, TNF-á, TGF-â and IL-10. Then, I treated BDL rats (N=5) with gadolinium chloride (GC; 10 mg/Kg body weight intravenous) and found reduced numbers of PIMs (p=0.061) at 48 hours post-treatment along with increased expression of TGF-â and IL-10.</p><p>I challenged control rats (N=5) and BDL rats (N=6) with Escherichia coli lipopolysaccharide (E. coli LPS; 0.1 mg/Kg body weight intravenous). All the BDL rats died within 3 hours of LPS challenge (100% mortality) while the normal LPS-treated rats were euthanized at 6 hours post-treatment. Histology and ED-1 staining showed dramatic increase in the number of septal monocytes/macrophages in BDL+LPS rats compared to normal LPS-treated rats (p=0.000). Staining of lung sections with an LPS antibody localized the LPS in lungs. RT-PCR analyses showed no differences in IL-1â transcript levels between LPS challenged BDL rats and LPS challenged control rats (p=0.746) but ELISA showed increase in IL-1â concentration in LPS challenged BDL rats compared to LPS challenged control rats (p=0.000). TNF-á mRNA (p=0.062) and protein (p=0.000) was increased in BDL+LPS rats compared to the control+LPS rats. Immuno-electron microscopy showed IL-1â and TNF-á in PIMs. BDL rats challenged with LPS showed increased expression of IL-10 mRNA and protein (p=0.000 & 0.002 respectively) in lungs compared to LPS challenged control rats. TGF-â mRNA did not change (p=0.128) but lower protein concentrations (p=0.000) were observed in LPS-treated control rats compared to BDL+LPS. </p><p> To further address the role of PIMs, I treated rats with GC at 6 hours or 48 hours (N=5 each) before LPS challenge. The mortality in the 6 hour group was 20% while all the rats in 48 hour group survived till 6 hours. Histology and ED-1 staining showed decrease in the number of intravascular cells in these groups compared to LPS treated BDL rats (p=0.039 for 6 hour group; p= 0.002 for 48 hour group). There were no differences in IL-1â mRNA in both 6 hour and 48 hour groups compared to the LPS challenged BDL rats (p=0.712 & 0.509 respectively). ELISA showed no decrease in IL-1â concentration in 6 hour GC-treated group but a decrease was noticed at 48 hours compared to LPS challenged BDL rats (p=0.455 & 0.008 respectively). TNF-á mRNA levels were not different between LPS-challenged GC-treated BDL rats and LPS-challenged BDL rats (p=0.499 & 0.297 for 6 hour & 48 hour GC groups respectively). But TNF-á concentration in 48 hour GC group (p=0.001) but not in 6 hour GC group (p=0.572) was lower in comparison to BDL+LPS group. IL-10 mRNA was decreased in both 6 hour and 48 hour GC groups (p=0.038 & 0.000 respectively) compared to LPS challenged BDL rats. ELISA showed decrease in IL-10 concentration in 48 hour GC group (p=0.030) but not in 6 hour GC group (p=0.420). TGF-â mRNA expression was decreased in 48 hour GC group (p=0.000) but not in 6 hour GC group (p=0.182). But GC treatment did not affect TGF-â concentrations. </p><p>The data from these experiments characterize a BDL model to study PIM biology, show PIMs pro-inflammatory potential and their possible role as a therapeutic target in lung inflammation.</p>