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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Estudo sobre efeitos do naftaleno e benzo(a) pireno em Trachinotus carolinus (Perciformes, Carangidae) utilizando biomarcadores citogenotóxicos, histopatológicos e bioquímicos / Study of the effects of naphthalene and benzo(a) pyrene in Trachinotus carolinus (Perciformes, Carangidae) using citogenotoxic, histopahological and biochemical biomarkers.

Thaís da Cruz Alves dos Santos 11 December 2009 (has links)
A exposição dos peixes a poluentes provoca danos nos organismos que podem ser identificados precocemente através de respostas biológicas. O presente estudo visou avaliar os efeitos do naftaleno e benzo(a)pireno em pampos da espécie Trachinotus carolinus. Foram avaliados os efeitos citogenotóxicos, histopatológicos e bioquímicos após exposições às concentrações de 0,9 M; 2,7 M e 8,1 M de NAP e BAP por períodos de 12, 24, 48 e 96 horas. O NAP causa quebra no DNA de eritrócitos de pampos em concentrações de 8,1 M e a partir de 12 horas de exposição. O BAP revelou ser genotóxico a partir da menor concentração e de 24 horas. A mutagenicidade de ambos os poluentes, avaliada através da indução de formação de micronúcleos e anormalidades nucleares eritrocitárias, também ocorre a partir de curtos períodos de exposição e freqüências de MN e ANE estão relacionadas com a duração da exposição. O período de exposição aos HPAs foi determinante na intensidade e severidade das lesões observadas nos tecidos dos peixes. A especificidade de CYP1A, observada segundo análise imunohistoquímica, ocorreu de maneira dose-dependente e evidenciada principalmente nos maiores períodos experimentais. Os poluentes orgânicos, nas condições experimentais utilizadas, não provocaram alteração significativa na atividade das enzimas catalase e GST da espécie. Os biomarcadores, citogenotóxicos e histopatológicos utilizados neste estudo, demonstraram ser ferramentas eficientes para aferir a toxicidade, genotoxicidade e mutagenicidade de NAP e BAP como também sua relação dose-resposta na espécie T. carolinus. / Effects of exposure of fish to pollutants can be identified through stress responses. The present study aims to evaluate the effects of naphthalene and benzo(a)pyrene in Florida pompanos, Trachinotus carolinus. Evidences from citogenotoxical, histopathological and biochemical studies showed that alterations caused by exposures to 0.9 M, 2.7 M and 8.1 M of NAP and BAP occurred within 12 to 96 hours. NAP at 8.1 M induced erythrocyte DNA strand breaks in pompanos since early periods of exposure. Genotoxic effects of BAP at the lowest concentration were documented soon after 24 hours of exposure. Mutagenotoxicity of both pollutants, as seen by the induction of MN and ENA, was revealed since early periods and their frequencies are related to the duration of exposure. Exposures to these PAHs, for longer periods, resulted in increased frequency and severity of lesions observed in fish tissues. Specificity of CYP1A, observed through immunohistochemical analyses, was related to the dose of the pollutants and mainly at longer periods of exposure. These organic pollutants, under the experimental conditions, did not interfere with the activity of liver catalase and GST of the species. The citogenotoxic and histopathologic biomarkers used in this study proved to be efficient tools to ascertain the toxicity, genotoxicity and mutagenesis of NAP and BAP, as well as their dose related response, in the species T. carolinus.
232

Dinâmica populacional, análise das concentrações de metais e utilização de biomarcadores em Mugil curema Valenciennes, 1836 do estuário de Santos e do sistema costeiro Cananéia-Iguape, São Paulo, Brasil / Population dynamics, metals concentrations analysis and use of biomarkers in Mugil curema Valenciennes, 1836 from Santos estuary and Cananeia-Iguape coastal system, São Paulo, Brazil

Wellington Silva Fernandez 13 December 2011 (has links)
O presente estudo teve como objetivo principal compreender a dinâmica populacional de Mugil curema em duas regiões distintas, tanto sob o ponto de vista oceanográfico como no de ocupação humana, e os possíveis impactos antrópicos no ciclo de vida da espécie. As amostras foram coletadas mensalmente no período de março/09 a fevereiro/10 no estuário de Santos e no período de maio/08 a abril/2009 no sistema costeiro Cananéia-Iguape, utilizando rede de abalo, rede de tarrafa e cerco fixo. Em laboratório os indivíduos coletados foram medidos (mm), pesados (g) e dissecados, para a retirada das gônadas, fígado, rim e otólitos para futuras analises. Os indivíduos de Mugil curema do estuário de Santos e do sistema costeiro Cananéia-Iguape, litoral do estado de São Paulo, Brasil, foram classificadas como pertencentes ao mesmo estoque, não existindo diferenças na estrutura em tamanho, na estrutura etária e na época de desova desses indivíduos. Também foi constatado altos valores do índice de lesões histológicas e da atividade EROD no tecido do fígado e altos níveis de bioacumulação de metais (bromo, cobre, cromo, ferro e zinco) nos tecidos do fígado e rim da espécie nas duas áreas estudadas. Todas as variáveis estimadas não apresentaram diferenças significativas entre as duas áreas de estudo. / The present study has mainly aimed at understanding the population dynamic of Mugil curema from two distinct areas at coast of the state of São Paulo (Brazil), both from oceanographic and human occupation point of view. Samples were collected monthly between March/09 and February/10 of the Santos estuary and between May/08 and April/09 of the Cananéia-Iguape coastal system using gillnet, seine net and fish trap. Collected individuals were measured (mm), weighted (g) and dissected for removal of gonads, liver, kidney and otoliths for further analysis. Specimens of Mugil curema from Santos estuary and Cananéia-Iguape costal system were classified as belonging to the same stock, since the results showed no difference in structure, size, age structure and spawning season. High values of the histological lesions index and EROD activity in the liver tissue as well as increased levels of bioaccumulation of metals (bromine, copper, chromium, iron and zinc) in the liver and kidney tissues were also found. All of the estimated variables for Mugil curema were not significantly different between the two regions.
233

Evolução da aspergilose pulmonar invasiva produzida em camundongos tratados com anticorpos monoclonais anti GR-1/Ly-6G e infectados com amostras de Aspergillus fumigatus que apresentaram distintos padrões de produção de elastase / Evolution of invasive pulmonary aspergillosis produced in mice treated with monoclonal antibodies anti GR-1/Ly-6G and infected with Aspergillus fumigatus strains which presented distincts patterns of production of elastase.

Raphael Luiz de Holanda e Silva 02 April 2012 (has links)
Aspergilose Pulmonar Invasiva é uma doença fúngica oportunista, causada principalmente por Aspergillus fumigatus, que acomete pacientes imunodeprimidos. Para melhor compreensão dessa micose inicialmente estabelecemos em camundongos C57BL/6 um modelo experimental de depleção de neutrófilos por inoculação intraperitoneal de anticorpos anti-GR-1/Ly-6G, confirmado por contagem total e diferencial de leucócitos sanguíneos. A seguir, avaliamos a evolução da infecção pulmonar experimental utilizando duas amostras de A. fumigatus, caracterizadas previamente em fraca (amostra 699) e forte (amostra 1753) produtoras de elastase. Nenhum dos animais imunocompetentes e infectados evoluiu para o óbito, no período de 7 dias de observação. Os animais neutropênicos, infectados por ambas as amostras, apresentaram 100% de mortalidade após 5 dias, com curvas de sobrevivência praticamente sobrepostas, sugerindo que a maior contribuição para a virulência foi a condição imunológica e não a atividade de elastase da amostra fúngica. Para análise do comprometimento pulmonar, os animais foram sacrificados nos tempos 24, 48 e 72 horas pós-infecção. Durante a evolução da infecção experimental foi observada uma redução da carga fúngica nos pulmões dos animais, para ambas as amostras de A. fumigatus, mas não foi observada uma redução da carga fúngica, diferenciada e estatisticamente significativa, entre os grupos de animais neutropênicos e imunocompetentes. O padrão celular do infiltrado inflamatório observado nos pulmões dos animais neutropênicos, infectados por qualquer uma das amostras de A. fumigatus, mostrou predominância de células mononucleares, em infiltrados difusos, indícios de angioinvasão e invasão brônquica com ruptura de fibras elásticas em ambas as estruturas, além de exuberância de filamentação dos conídios para ambas as amostras fúngicas, desde os tempos iniciais da infecção experimental. O processo inflamatório observado nos pulmões dos animais imunocompetentes, infectados por ambas as amostras de fungos, foi constituído nos tempos iniciais por neutrófilos e se tornou exuberante após 72 horas, com predomínio de macrófagos. Foi observada integridade de vasos sanguíneos e discreta ruptura de parede brônquica no parênquima pulmonar. Para estes animais, salienta-se a ausência de transformação dos conídios de A. fumigatus em hifas para a amostra 699, em todos os períodos de observação. A contagem total de leucócitos no lavado broncoalveolar (LBA) foi significativamente maior, 72 horas pós-infecção, para os animais neutropênicos e imunocompetentes, infectados por ambas as amostras do fungo. A contagem diferencial revelou a presença de macrófagos e neutrófilos, com a primeira célula sempre em maior quantidade no LBA dos animais neutropênicos em comparação com os animais imunocompetentes, independentemente do período da infecção e da amostra fúngica infectante. Ao contrário, o número de neutrófilos foi sempre mais relevante nos animais imunocompetentes. Por microscopia eletrônica de transmissão foi observado que a interação do fungo (conídios ou hifas) com as células de defesa do LBA envolveu íntima adesão e fusão entre os componentes de superfície de ambas as células. A presença de hemoglobina no LBA foi oriunda de lesão alvéolo-capilar causada pelo crescimento e invasão provocados pelas amostras fúngicas ou por lesão determinada pela própria reação inflamatória. Concluímos que os neutrófilos são essenciais na defesa contra A. fumigatus, pois na ausência dessa população celular os fungos rapidamente invadem e lesam o parênquima pulmonar. No entanto, deve-se considerar que a simples presença do fungo em animais imunocompetentes induz a migração de neutrófilos para o sítio da infecção, os quais também causam dano tecidual. As amostras de A. fumigatus com perfis distintos de produção de elastase não refletiram em diferenças significantes para a mortalidade ou gênese das lesões pulmonares observadas em camundongos neutropênicos, sugerindo que embora a elastase contribua para a ruptura das fibras elásticas observadas no tecido pulmonar, outros fatores de virulência, como a morfogênese, podem assumir um papel mais relevante para a patogênese da API experimental. / Invasive Pulmonary Aspergillosis (IPA) is an opportunistic fungal disease, caused mainly by Aspergillus fumigatus, that affects immunocompromised patients. To better understand this mycoses, we originally established in C57BL/6 mice an experimental model of neutrophils depletion by intraperitoneal inoculation of antibodies anti GR-1/Ly-6G, confirmed by total and differential leukocyte counts from blood. Next, we evaluated the evolution of experimental pulmonary infection using two strains of A. fumigatus, previously characterized as weak (strain 699) and strong (strain 1753) elastase producers. None of immunocompetent infected mice died with 7 days of observation, while neutropenic mice, infected with both strains, showed 100% mortality after 5 days, with survival curves nearly overlap, suggesting that the major contribution to the virulence was the immune status instead of elastase activity of each fungal strain. For analysis of lung parenchyma, mice were sacrificed 24, 48 and 72 hours post-infection. During the course of experimental infection it was observed a reduction of fungal burden in the lungs, for both strains of A. fumigatus, but this reduction was not statistically significant between the infected groups (neutropenic and immunocompetent). The cellular pattern of the inflammatory infiltrate observed in lungs from neutropenic mice, infected with both strains of A. fumigatus, revealed a predominance of mononuclear cells, a diffuse pattern and clear evidences of angioinvasion, bronchial disruption with break of elastic fibers in both structures, besides exuberance of conidia filamentation for both fungal strains, since the early period of experimental infection. The inflammatory process observed in lungs from immunocompetent mice, infected with both fungal strains, was composed on early times by neutrophils and became exuberant after 72 hours, with predominance of macrophages. It was observed integrity of blood vessels and moderate bronchial wall disruption in lung parenchyma. A relevant observation was the lack of transformation of conidia in hyphae for 699 A. fumigatus strain, in all periods of observation. Total leukocytes count in bronchoalveolar lavage (BAL) was significantly higher at 72 hours post-infection for both groups infected with both strains. The differential count revealed the presence of macrophages and neutrophils, with the former always in greater percentage in BAL from neutropenic mice and the latter always more elevated in immunocompetent group. Analysis by transmission electron microscopy demonstrated that the interaction of fungal structures (conidia or hyphae) with the defense cells (neutrophlis or macrophages) of BAL involved an intimate adhesion and fusion between the surface components from both cells. The presence of hemoglobin in BAL was a result of alveolar injury caused by the fungal development and invasion, but also by injuries determined by the inflammatory process itself. We concluded that neutrophils have a critical role against A. fumigatus since the pathogen quickly invades and damages the lung parenchyma in its absence. However, we must consider that the mere presence of A. fumigatus in immunocompetent mice induces the neutrophils migration to the infection site, which can also cause a tissue injury. Strains of A. fumigatus with distinct patterns of elastase production did not reflect in significant differences in mortality or origin of pulmonary lesions observed in neutropenic mice, suggesting that although elastase contributes to elastic disruptions observed in pulmonary tissue, another virulence factors, such as morphogenesis, can assume a more relevant role for pathogenesis of experimental IPA.
234

ASPECTOS EPIDEMIOLÓGICOS, CLÍNICOS E HISTOPATOLÓGICOS DE OSTEOSSARCOMA EM MENORES DE 20 ANOS EM UM CENTRO DE ASSISTÊNCIA DE ALTA COMPLEXIDADE EM ONCOLOGIA (CACON) MARANHÃO) / PHYSICIANS AND HISTOPATHOLOGICAL EPIDEMIOLOGISTS ASPECTS OF OSTEOSSARCOMA IN MINORS OF 20 YEARS IN A CENTER OF ASSISTANCE OF HIGH COMPLEXITY IN ONCOLOGY(CACON) MARANHÃO

Mello, Francisco Amazonas de Assis 14 December 2006 (has links)
Made available in DSpace on 2016-08-19T18:16:08Z (GMT). No. of bitstreams: 1 FRANCISCO AMAZONAS ASSIS MELO.pdf: 267824 bytes, checksum: 4afd9a9968a7d18ef592b9bc3ca03f1e (MD5) Previous issue date: 2006-12-14 / Osteosarcoma is a malignance soft tumor, more frequently in children, teenagers and young adults and it represents 20% of all kind of sarcomas. It was aimed to describe epidemiological aspects such as age, gender, location and to classify kinds of osteosarcoma according to histopathological diagnose and histological grading and to relate it with clinical stage TNM data. It was done an observing and descriptive study in 26 (twenty-six) patients with age less than 20 years old with osteosarcoma treated in a High Complexity Oncology Assistance Centre called Instituto de Maranhense de Oncologia Aldenora Bello since April of 1996 to April of 2006. Variables were compared to Brazilian population database denominated PNAD from the year of 2005. Clinical, histopathological and histological grading aspects supported data to tumor classification. It was analyzed report books from these 26 patients in which was observed that age had a variety from 5 to 20, 14 were from female gender (53,8%) and 12 (46,2%) from male gender; twenty had brown skin (76,5%), white skin (15,4%) and 14 (53,8%) has come from country side of Maranhão. Most prevalent tumor locality was left femur (42,3%). Among the 22 pacients with conventional osteosarcoma, 13 were (50,0%) the mix type, followed by telangiectasic (11,5%; 3/26) and periosteal (3,8%; 1/26). There was a predominance of histology grade III (high grade) with 65,4%; grade II (low grade) with 30,8%. According to TNM stage, 15 (57,7%) were T1NxM0 and 7 were T1NxM1a, clinical stage was predominantly IIA (57,6%) followed by IVA (30,7%). From 10 patients initially diagnosed with mestastatic disease when admitted, 8 (34,6%) had lung implantation. The type of ostesarcomas, even with same clinical stage, may present outcome and time of survival different from each other and it depends on tumor grading. The research performed in the High Complexity Centre of Oncology in São Luís Maranhão had shown that conventional tumor and the ones with high grade was the most predominant. / O osteossarcoma é um tumor mesenquimal maligno, mais freqüente em crianças, adolescentes e adultos jovens, representando 20% de todos os sarcomas. Descreve-se aspectos epidemiológicos, enfatizando a faixa etária, sexo e procedência, além de classificar os tipos de osteossarcoma de acordo com o diagnóstico anatomopatológico e graus histológicos, e relacionar os achados com o estadiamento por TNM. Foi realizado um estudo observacional e descritivo em 26 (vinte e seis) pacientes com diagnóstico de osteossarcoma em menores de vinte anos de idade em um Centro de Assistência de Alta Complexidade em Oncologia (CACON), denominado Instituto Maranhense de Oncologia Aldenora Bello em São Luís-Maranhão, durante o período de abril de 1996 a abril de 2006. As variáveis foram comparadas com os percentuais levantados pela Pesquisa Nacional por Amostragem de Domicílios (PNAD) de 2005. Os aspectos clínicos, histopatológicos e graus histológicos constituíram os dados que deram suporte à classificação do tumor. Foram analisados os prontuários de 26 pacientes onde se observou que a idade variou de 5 a 20 anos, sendo 14 (53,8%) do sexo feminino e 12 (46,2%) do sexo masculino; vinte era da cor parda equivalendo 76,9%, seguindo-se a cor branca com 15,4 %, sendo que 14 (53,8%) eram oriundos do interior do estado. A localização mais comum do tumor foi no fêmur esquerdo (42,3%). Dentre os 22 pacientes com osteossarcoma convencional 13 (50,0%;13/26) eram do tipo misto seguido do tipo telangiectásico (11,5%;3/26) e periosteal (3,8%;1/26). Houve predomínio do grau histológico III (alto grau), compreendendo 65,4%; seguido do grau II (baixo grau) com 30,8%. Segundo o estadiamento, 15 (57,7%) eram T1NXM0 e 7 (26,9%) eram T1NXM1a, além de outros, cujo estadiamento clínico predominantemente foi IIA (57,6%) e IVA (30,7%). Dos dez pacientes com doença metastática ao estadiamento quando da admissão, 8 (34,6%) tinham predominantemente metástases pulmonares. Os tipos de osteossarcomas mesmo apresentando estadiamento clínico igual podem apresentar prognóstico e diferente sobrevida, e isto depende do grau de diferenciação tumoral determinado pelo estudo do grau histológico. A pesquisa realizada no CACON em São Luís-Ma demonstrou que o tipo convencional e os de alto grau detiveram a maioria dos casos.
235

Evolução da aspergilose pulmonar invasiva produzida em camundongos tratados com anticorpos monoclonais anti GR-1/Ly-6G e infectados com amostras de Aspergillus fumigatus que apresentaram distintos padrões de produção de elastase / Evolution of invasive pulmonary aspergillosis produced in mice treated with monoclonal antibodies anti GR-1/Ly-6G and infected with Aspergillus fumigatus strains which presented distincts patterns of production of elastase.

Silva, Raphael Luiz de Holanda e 02 April 2012 (has links)
Aspergilose Pulmonar Invasiva é uma doença fúngica oportunista, causada principalmente por Aspergillus fumigatus, que acomete pacientes imunodeprimidos. Para melhor compreensão dessa micose inicialmente estabelecemos em camundongos C57BL/6 um modelo experimental de depleção de neutrófilos por inoculação intraperitoneal de anticorpos anti-GR-1/Ly-6G, confirmado por contagem total e diferencial de leucócitos sanguíneos. A seguir, avaliamos a evolução da infecção pulmonar experimental utilizando duas amostras de A. fumigatus, caracterizadas previamente em fraca (amostra 699) e forte (amostra 1753) produtoras de elastase. Nenhum dos animais imunocompetentes e infectados evoluiu para o óbito, no período de 7 dias de observação. Os animais neutropênicos, infectados por ambas as amostras, apresentaram 100% de mortalidade após 5 dias, com curvas de sobrevivência praticamente sobrepostas, sugerindo que a maior contribuição para a virulência foi a condição imunológica e não a atividade de elastase da amostra fúngica. Para análise do comprometimento pulmonar, os animais foram sacrificados nos tempos 24, 48 e 72 horas pós-infecção. Durante a evolução da infecção experimental foi observada uma redução da carga fúngica nos pulmões dos animais, para ambas as amostras de A. fumigatus, mas não foi observada uma redução da carga fúngica, diferenciada e estatisticamente significativa, entre os grupos de animais neutropênicos e imunocompetentes. O padrão celular do infiltrado inflamatório observado nos pulmões dos animais neutropênicos, infectados por qualquer uma das amostras de A. fumigatus, mostrou predominância de células mononucleares, em infiltrados difusos, indícios de angioinvasão e invasão brônquica com ruptura de fibras elásticas em ambas as estruturas, além de exuberância de filamentação dos conídios para ambas as amostras fúngicas, desde os tempos iniciais da infecção experimental. O processo inflamatório observado nos pulmões dos animais imunocompetentes, infectados por ambas as amostras de fungos, foi constituído nos tempos iniciais por neutrófilos e se tornou exuberante após 72 horas, com predomínio de macrófagos. Foi observada integridade de vasos sanguíneos e discreta ruptura de parede brônquica no parênquima pulmonar. Para estes animais, salienta-se a ausência de transformação dos conídios de A. fumigatus em hifas para a amostra 699, em todos os períodos de observação. A contagem total de leucócitos no lavado broncoalveolar (LBA) foi significativamente maior, 72 horas pós-infecção, para os animais neutropênicos e imunocompetentes, infectados por ambas as amostras do fungo. A contagem diferencial revelou a presença de macrófagos e neutrófilos, com a primeira célula sempre em maior quantidade no LBA dos animais neutropênicos em comparação com os animais imunocompetentes, independentemente do período da infecção e da amostra fúngica infectante. Ao contrário, o número de neutrófilos foi sempre mais relevante nos animais imunocompetentes. Por microscopia eletrônica de transmissão foi observado que a interação do fungo (conídios ou hifas) com as células de defesa do LBA envolveu íntima adesão e fusão entre os componentes de superfície de ambas as células. A presença de hemoglobina no LBA foi oriunda de lesão alvéolo-capilar causada pelo crescimento e invasão provocados pelas amostras fúngicas ou por lesão determinada pela própria reação inflamatória. Concluímos que os neutrófilos são essenciais na defesa contra A. fumigatus, pois na ausência dessa população celular os fungos rapidamente invadem e lesam o parênquima pulmonar. No entanto, deve-se considerar que a simples presença do fungo em animais imunocompetentes induz a migração de neutrófilos para o sítio da infecção, os quais também causam dano tecidual. As amostras de A. fumigatus com perfis distintos de produção de elastase não refletiram em diferenças significantes para a mortalidade ou gênese das lesões pulmonares observadas em camundongos neutropênicos, sugerindo que embora a elastase contribua para a ruptura das fibras elásticas observadas no tecido pulmonar, outros fatores de virulência, como a morfogênese, podem assumir um papel mais relevante para a patogênese da API experimental. / Invasive Pulmonary Aspergillosis (IPA) is an opportunistic fungal disease, caused mainly by Aspergillus fumigatus, that affects immunocompromised patients. To better understand this mycoses, we originally established in C57BL/6 mice an experimental model of neutrophils depletion by intraperitoneal inoculation of antibodies anti GR-1/Ly-6G, confirmed by total and differential leukocyte counts from blood. Next, we evaluated the evolution of experimental pulmonary infection using two strains of A. fumigatus, previously characterized as weak (strain 699) and strong (strain 1753) elastase producers. None of immunocompetent infected mice died with 7 days of observation, while neutropenic mice, infected with both strains, showed 100% mortality after 5 days, with survival curves nearly overlap, suggesting that the major contribution to the virulence was the immune status instead of elastase activity of each fungal strain. For analysis of lung parenchyma, mice were sacrificed 24, 48 and 72 hours post-infection. During the course of experimental infection it was observed a reduction of fungal burden in the lungs, for both strains of A. fumigatus, but this reduction was not statistically significant between the infected groups (neutropenic and immunocompetent). The cellular pattern of the inflammatory infiltrate observed in lungs from neutropenic mice, infected with both strains of A. fumigatus, revealed a predominance of mononuclear cells, a diffuse pattern and clear evidences of angioinvasion, bronchial disruption with break of elastic fibers in both structures, besides exuberance of conidia filamentation for both fungal strains, since the early period of experimental infection. The inflammatory process observed in lungs from immunocompetent mice, infected with both fungal strains, was composed on early times by neutrophils and became exuberant after 72 hours, with predominance of macrophages. It was observed integrity of blood vessels and moderate bronchial wall disruption in lung parenchyma. A relevant observation was the lack of transformation of conidia in hyphae for 699 A. fumigatus strain, in all periods of observation. Total leukocytes count in bronchoalveolar lavage (BAL) was significantly higher at 72 hours post-infection for both groups infected with both strains. The differential count revealed the presence of macrophages and neutrophils, with the former always in greater percentage in BAL from neutropenic mice and the latter always more elevated in immunocompetent group. Analysis by transmission electron microscopy demonstrated that the interaction of fungal structures (conidia or hyphae) with the defense cells (neutrophlis or macrophages) of BAL involved an intimate adhesion and fusion between the surface components from both cells. The presence of hemoglobin in BAL was a result of alveolar injury caused by the fungal development and invasion, but also by injuries determined by the inflammatory process itself. We concluded that neutrophils have a critical role against A. fumigatus since the pathogen quickly invades and damages the lung parenchyma in its absence. However, we must consider that the mere presence of A. fumigatus in immunocompetent mice induces the neutrophils migration to the infection site, which can also cause a tissue injury. Strains of A. fumigatus with distinct patterns of elastase production did not reflect in significant differences in mortality or origin of pulmonary lesions observed in neutropenic mice, suggesting that although elastase contributes to elastic disruptions observed in pulmonary tissue, another virulence factors, such as morphogenesis, can assume a more relevant role for pathogenesis of experimental IPA.
236

Establishing biological and environmental drivers that influence the health assessment index as a biomonitoring tool

Phala, Balance Matseilane January 2019 (has links)
Thesis (MSc.) Zoology)) -- University of Limpopo, 2019 / In South Africa, a high anthropogenic demand of water for domestic, recreational, agricultural, urbanisation and industrial purposes has placed enormous pressure on freshwater resources and has led to a decline in water quality. In addition to measuring water quality variables, the health assessment index (HAI) advocated by AvenantOldewage and Swanepoel (1993), and modified by Crafford and Avenant-Oldewage (2009) by incorporating the inverted parasite index (IPI), and adapted further by Madanire-Moyo et al. (2012) who excluded the white blood cells counts, has been used as a rapid and inexpensive means of assessing and monitoring fish health and, in turn, the state of aquatic ecosystems. However, few studies have evaluated the latter approach in conjunction with other biomonitoring indices to assess the water quality of impoundments. Thus, the aim of this study was twofold. The first was to evaluate the HAI adapted by Madanire-Moyo et al. (2012) as a means to establish the health status of Oreochromis mossambicus (Peters, 1852) sampled from various impoundments based on a once-off survey. The second was to establish if the adapted HAI, in conjunction with selected biomonitoring indices and environmental variables, could describe monthly and seasonal fluctuations of O. mossambicus health. Once-off surveys were conducted between April and May 2016 at five impoundments. The Luphephe-Nwanedi Dam located in the upper catchment of the Limpopo River System and Rhenosterkop Dam situated in the Elands River, a tributary of the Olifants River System, served as control sites due to little or no anthropogenic activities occurring in their catchment areas. In addition, surveys were conducted at Loskop and Flag Boshielo dams and Phalaborwa Barrage situated in the main stem of the Olifants River for comparison purposes. The latter three impoundments were selected because they vary in water quality and pollution levels. Monthly surveys were carried out at Flag Boshielo Dam from February 2016 to February 2017 to establish if the biomonitoring tools and the quantification of water and sediment quality variables, could describe and predict seasonal fluctuations in the health of O. mossambicus. To this end, water quality variables were measured during each survey. Water and sediment samples were collected for analysis of nutrients and metals. Oreochromis mossambicus were collected using gill nets. Fish health was assessed using the adapted HAI that was based on observing parasite burden, haematocrit determination and anomalies in body tissues and organs in conjunction with determining gonad and iv hepato-somatic indices, the condition factor, blood glucose levels, microscopy analyses of fish gills and metal concentrations in fish muscle tissues. Water quality in terms of pH, total dissolved solids and electrical conductivity, nutrients and some aqueous and sediment metals exhibited significant differences (p ˂ 0.05) between impoundments surveyed with water quality from good to poor being in the order of: Luphephe-Nwanedi Dams ˂ Rhenosterkop Dam ˂ Loskop Dam ˂ Phalaborwa Barrage ˂ Flag Boshielo Dam. The HAI scores varied significantly (p ˂ 0.0001) between impoundments and substantiated water quality variables results during once off surveys, indicating that the health of fish from Flag Boshielo Dam were most affected when compared to the health of fish surveyed from the other impoundments. Findings from monthly surveys conducted at Flag Boshielo Dam indicated better conditions in terms of water quality variables during a period of high inflow as opposed to periods of low inflow. The HAI scores obtained for fish exhibited significant (p ˂ 0.0001) differences between the months surveyed and were found to be in agreement with the water quality findings, indicating that flow regimes and water quality of an impoundment have an impact on fish health. The condition and somatic indices findings did not seem to be sensitive enough to discriminate between the impoundments during the once off surveys. While during monthly surveys, these indices were significantly (p ˂ 0.0001) different between the months, showing to be affected by seasonal fluctuations. Knowledge of the HAI in conjunction with blood glucose levels, gill histopathology and the arithmetic mean thickness of gill epithelium (Har) best described the health of fish in both the once off and monthly surveys. In conclusion, the findings of this study emphasised the HAI premise that fish from more polluted sites would be more impacted as opposed to less impacted sites, making the HAI adapted by Madanire-Moyo et al. (2012) an effective and rapid biomonitoring tool that can be used in the field. Furthermore, this study proved that the HAI can be used either solely or in association with the parasite index (PI) or IPI depending on the objectives of the study, as no pronounced differences were evident when using HAI, HAI with PI and HAI with IPI. / National Research Foundation (NRF) and Water Research Commission (WRC)
237

Magnetic resonance imaging for improved treatment planning of the prostate

Venugopal, Niranjan 11 January 2012 (has links)
Prostate cancer is the most common malignancy afflicting Canadian men in 2011. Physicians use digital rectal exams (DRE), blood tests for prostate specific antigen (PSA) and transrectal ultrasound (TRUS)-guided biopsies for the initial diagnosis of prostate cancer. None of these tests detail the spatial extent of prostate cancer - information critical for using new therapies that can target cancerous prostate. With an MRI technique called proton magnetic resonance spectroscopic imaging (1H-MRSI), biochemical analysis of the entire prostate can be done without the need for biopsy, providing detailed information beyond the non-specific changes in hardness felt by an experienced urologist in a DRE, the presence of PSA in blood, or the “blind-guidance” of TRUS-guided biopsy. A hindrance to acquiring high quality 1H-MRSI data comes from signal originating from fatty tissue surrounding prostate that tends to mask or distort signal from within the prostate, thus reducing the overall clinical usefulness of 1H-MRSI data. This thesis has three major areas of focus: 1) The development of an optimized 1H-MRSI technique, called conformal voxel magnetic resonance spectroscopy (CV-MRS), to deal the with removal of unwanted lipid contaminating artifacts at short and long echo times. 2) An in vivo human study to test the CV-MRS technique, including healthy volunteers and cancer patients scheduled for radical prostatectomy or radiation therapy. 3) A study to determine the efficacy of using the 1H-MRSI data for optimized radiation treatment planning using modern delivery techniques like intensity modulated radiation treatment. Data collected from the study using the optimized CV-MRS method show significantly reduced lipid contamination resulting in high quality spectra throughout the prostate. Combining the CV-MRS technique with spectral-spatial excitation further reduced lipid contamination and opened up the possibility of detecting metabolites with short T2 relaxation times. Results from the in vivo study were verified with post-histopathological data. Lastly, 1H-MRSI data was incorporated into the radiation treatment planning software and used to asses tumour control by escalating the radiation to prostate lesions that were identified by 1H-MRSI. In summary, this thesis demonstrates the clinical feasibility of using advanced spectroscopic imaging techniques for improved diagnosis and treatment of prostate cancer.
238

Validation de l'échographie des bulles tympaniques pour le diagnostic d'otite moyenne chez le veau

Bernier Gosselin, Véronique 12 1900 (has links)
L'otite moyenne est une condition fréquente chez le veau et peut parfois être subclinique, rendant difficile son diagnostic à la ferme. L'objectif de cette étude est d’estimer la sensibilité et la spécificité de l'échographie des bulles tympaniques pour le diagnostic d'otite moyenne clinique et subclinique et de déterminer sa répétabilité. Quarante veaux âgés entre 19 et 50 jours ont été sélectionnés dans une ferme de veaux de grain, en fonction des résultats de l'échographie réalisée à la ferme (A). L'échographie a été réalisée une seconde fois par le même échographiste (A') et par un second échographiste (B), et le diagnostic noté pour chaque bulle tympanique comme étant négatif, suspect ou positif. Les images ont été enregistrées pour relecture et le diagnostic noté. Les veaux ont été euthanasiés, soumis en nécropsie et l'histologie a été utilisée comme méthode de référence. À l'histologie, 45 bulles tympaniques étaient atteintes d'otite moyenne et 35 bulles tympaniques étaient saines. Selon l'échographiste et la classification des bulles tympaniques suspectes, la sensibilité de l'échographie variait de 32% à 63% et la spécificité variait de 84% à 100%. La répétabilité était modérée, avec des valeurs de kappa de 0,53 entre A' et B, de 0,48 entre A et A', et de 0,58 et 0,75 pour la relecture de leurs images par A' et B respectivement. / Otitis media is a common disease in calves but can remain subclinical, making diagnosis challenging on the farm. The objective of this study is to estimate the sensitivity and specificity of the ultrasound imaging technique of tympanic bulla for the diagnosis of clinical and subclinical otitis media, and to determine its repeatability. Forty calves 19-50 days of age were selected from a veal calf farm, on the basis of results of ultrasound examination performed on the farm (A). Ultrasound examination was performed a second time by the same ultrasonographer (A') and by another ultrasonographer (B), and diagnosis was recorded for both tympanic bulla as negative, suspicious or positive. Images were recorded for further re-reading. Calves were euthanized and submitted for necropsy, and histopathologic diagnosis was used as gold standard. Based upon histology, 45 bullae were affected with otitis media and 35 bullae were unaffected. Depending on ultrasonographer and on classification of suspicious bullae, sensitivity varies from 32% to 63% and specificity varies from 84% to 100%. Repeatability is moderate, with kappa values of 0.53 for A'-B, 0.48 for A-A', and 0.58 and 0.75 for re-reading of A' and B, respectively.
239

Magnetic resonance imaging for improved treatment planning of the prostate

Venugopal, Niranjan 11 January 2012 (has links)
Prostate cancer is the most common malignancy afflicting Canadian men in 2011. Physicians use digital rectal exams (DRE), blood tests for prostate specific antigen (PSA) and transrectal ultrasound (TRUS)-guided biopsies for the initial diagnosis of prostate cancer. None of these tests detail the spatial extent of prostate cancer - information critical for using new therapies that can target cancerous prostate. With an MRI technique called proton magnetic resonance spectroscopic imaging (1H-MRSI), biochemical analysis of the entire prostate can be done without the need for biopsy, providing detailed information beyond the non-specific changes in hardness felt by an experienced urologist in a DRE, the presence of PSA in blood, or the “blind-guidance” of TRUS-guided biopsy. A hindrance to acquiring high quality 1H-MRSI data comes from signal originating from fatty tissue surrounding prostate that tends to mask or distort signal from within the prostate, thus reducing the overall clinical usefulness of 1H-MRSI data. This thesis has three major areas of focus: 1) The development of an optimized 1H-MRSI technique, called conformal voxel magnetic resonance spectroscopy (CV-MRS), to deal the with removal of unwanted lipid contaminating artifacts at short and long echo times. 2) An in vivo human study to test the CV-MRS technique, including healthy volunteers and cancer patients scheduled for radical prostatectomy or radiation therapy. 3) A study to determine the efficacy of using the 1H-MRSI data for optimized radiation treatment planning using modern delivery techniques like intensity modulated radiation treatment. Data collected from the study using the optimized CV-MRS method show significantly reduced lipid contamination resulting in high quality spectra throughout the prostate. Combining the CV-MRS technique with spectral-spatial excitation further reduced lipid contamination and opened up the possibility of detecting metabolites with short T2 relaxation times. Results from the in vivo study were verified with post-histopathological data. Lastly, 1H-MRSI data was incorporated into the radiation treatment planning software and used to asses tumour control by escalating the radiation to prostate lesions that were identified by 1H-MRSI. In summary, this thesis demonstrates the clinical feasibility of using advanced spectroscopic imaging techniques for improved diagnosis and treatment of prostate cancer.
240

Ações de bactérias láticas de duas marcas comerciais de leites fermentados sobre o ganho de peso e parâmetros hematológicos e histopatológicos de ratos wistar fazendo uso de indometacina

Oliveira, Cybelle Pereira de 29 September 2009 (has links)
Made available in DSpace on 2015-04-17T14:49:17Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 884266 bytes, checksum: b2fc6505d10abdbaaf135855e8e6fd2c (MD5) Previous issue date: 2009-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Researches demonstrate that the consumption of fermented milk is beneficial to the health due to the presence of lactic acid bacteria and of the products of the metabolism produced by them during the fermentation of the milk. The objective of this work was to evaluate the action of the lactic bacterias of two commercial marks of fermented milks, one cultivated with Lactobacillus paracasei (L1) and other with Lactobacillus casei (L2), on the weight gain and hematologic and histopathologic parameters of rats Wistar making the indomethacin use. The choice of the drug based on the hypothesis of the existence of the protection of the digestive system and of the histology of the organs of the animals against the possible aggression of the nonsteroidal anti-inflammatory for the concomitant administration of the fermented milks. Three lots of each fermented milk were used, taking place the count of the viability of the lactic bacterias, gram coloration, catalase and morphologic identification. Simultaneously, 60 rats Wistar males with 90 days, consuming commercial ration and water ad libitum, were divided in 6 groups of 10, being the group LP added of L1; LP + D of L1 + drug; C (control) of water; D, of drug; LC, of L2; and LC + D, of L2 + drug. The animals received the fermented milks (5mL/Kg/day) and/or the drug indomethacin (2mg/Kg/day) for gavage for 40 days, enrolling the weekly weights. After the sacrifice, blood samples were collected for the accomplishment of hemograms and it was verified the weight of the kidneys, spleens and livers, taking place the histopathology of these organs and of the stomachs and intestines. The obtained results were treated with ANOVA, Tukey, Friedman, Duncan, Kruskall-wallis and Wilcoxon (p<0,05), being used the statistical package R. The strains of L1 and L2 resulted in catalase negative, gram positive and morphology of bacilli, presenting final counts of bacteria with superior values to 106 UFC. The fermented milks added to the diets of LP and LC and the addition of the drug to D didn't influence in the weekly weight gain of the animals, but LP+D and LC+D statistically differed of C and D, suggesting there to be interaction among drug-food. In the difference among the initial and final weight of the animals, the groups that received fermented milk resembled each other to the control, except the group LP whose weight gain was inferior; D also presented deficit of weight gain in relation to the group C. The diets didn't influence in the weights of the kidneys of the experimental groups, LP just presented significant difference in terms of spleen weight in relation to the other groups and the weights of the livers of the groups LP, D and LC+D differed in relation to the control group, where D resulted in superior weight of C and LP and LC+D obtained inferior weights to the control group. In the blood parameters, the groups didn't differ to each other in the red and white series, nor in the differential leucocyte count, if not verifying immunostimulatory effects; already in the counts of the platelets, some groups presented statistical difference, however the obtained results were inside of the allowed. The histopathological analysis had not evidenced histology alterations in the stomachs, livers, kidneys and spleens, meeting discreet infiltrated of lymphoid cells in the own sheet of the intestine of the experimental groups. / Pesquisas demonstram que o consumo de leite fermentado é benéfico à saúde devido à presença de bactérias láticas e dos metabólitos produzidos por elas durante a fermentação do leite. O objetivo deste trabalho foi avaliar a ação das bactérias láticas de duas marcas comerciais de leites fermentados, uma cultivada com Lactobacillus paracasei (L1) e outra com Lactobacillus casei (L2), sobre o ganho de peso e parâmetros hematológicos e histopatológicos de ratos Wistar fazendo o uso de indometacina. A escolha da droga baseou-se na hipótese da existência da proteção do trato digestivo e da histologia dos órgãos dos animais contra a possível agressão do antiinflamatório pela administração concomitante dos leites fermentados. Foram utilizados três lotes de cada leite fermentado, realizando-se a contagem da viabilidade das bactérias láticas, coloração de gram, catalase e identificação morfológica. Simultaneamente, 60 ratos Wistar machos com 90 dias, consumindo ração comercial e água ad libitum, foram divididos em 6 grupos de 10, sendo o grupo LP adicionado de L1; LP + D de L1 + droga; C (controle) de água; D, de droga; LC, de L2; e LC + D, de L2 + droga. Os animais receberam os leites fermentados (5mL/Kg/dia) e/ou a droga indometacina (2mg/Kg/dia) por gavagem durante 40 dias, registrandose os pesos semanais. Após o sacrifício, amostras sanguíneas foram coletadas para a realização de hemogramas e verificou-se o peso dos rins, baços e fígados, realizando-se a histopatologia destes órgãos e dos estômagos e intestinos. Os dados obtidos foram tratados com ANOVA, Tukey, Friedman, Duncan, Kruskall-wallis e Wilcoxon (p<0,05), utilizando-se o pacote estatístico R. As cepas de L1 e L2 resultaram em catalase negativas, gram positivas e morfologia de bacilos, apresentando contagens finais de bactérias com valores superiores a 106 UFC/mL. Os leites fermentados adicionados às dietas de LP e LC e a adição da droga ao grupo D não influenciaram no ganho de peso semanal dos animais, mas LP+D e LC+D diferiram estatisticamente de C e D, sugerindo haver interação entre droga-alimento. Na diferença entre o peso inicial e final dos animais, os grupos que receberam leite fermentado assemelharam-se ao controle, exceto o grupo LP cujo ganho de peso foi inferior; D também apresentou déficit de ganho de peso em relação ao grupo C. As dietas não influenciaram nos pesos dos rins dos grupos experimentais, apenas LP apresentou diferença significativa em termos de peso de baço em relação aos demais grupos e os pesos dos fígados dos grupos LP, D e LC+D diferiram em relação ao grupo controle, onde D resultou em peso superior a C e LP e LC+D obtiveram pesos inferiores ao grupo controle. Nos parâmetros sanguíneos, os grupos não diferiram entre si nas séries vermelha e branca, nem na contagem diferencial dos leucócitos, não se constatando efeito imunoestimulador; já nas contagens das plaquetas, alguns grupos apresentaram diferença estatística, porém os resultados obtidos encontraramse dentro da faixa permitida. As análises histopatológicas não evidenciaram alterações na histologia dos estômagos, fígados, rins e baços, apresentando discreto infiltrado de células linfóides na lâmina própria do intestino dos grupos experimentais.

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