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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.
1

In-Vitro Analysis of the Respiratory Toxicities of Fossil Fuel Combustion Ashes

Okeson, Carl D. January 2006 (has links)
Epidemiological studies have linked exposure to elevated levels of airborne particulate matter with increased incidences of several types of respiratory disease, hospital admissions and morbidity. Millions of tons of airborne particulate matter are generated and released into the atmosphere each year. However, particulate matter resulting from the combustion of fuel oil and coal are of particular concern, because they are generally composed of small particles that can easily penetrate deep into the lungs, and can contain significant concentrations of toxic transition metals, such as zinc, iron and vanadium. Pulmonary toxicity (i.e. damage caused to lung tissues) of particulate matter is currently evaluated via time-consuming in-vivo testing, or via in-vitro testing. Compared to in-vivo testing, in-vitro testing offers significant advantages in terms of time savings and sample throughput. Unfortunately, the number of in-vitro testing methods are currently very limited, and do not allow a thorough investigation of the mechanisms of particulate matter toxicity. In light of these issues, the goals of the study described here were three-fold: *To adapt several in-vitro toxicity assays currently used in other applications to use in measuring particulate matter toxicity on lung cell layers; *To use these adapted assays to quantify the toxicity of numerous types of oil and coal ashes with varying particle sizes and transition metal concentrations, and; *To use the same assays to quantify the toxicities of several transition metals found in coal and oil ashes to better understand their relative contributions to overall particulate matter toxicity. Three colorimetric in-vitro assays were chosen for adaptation, and proved effective in measuring adverse cellular response to particulate matter exposure. Particle size was shown to have a large effect on the overall cytotoxicity of particulate matter; fine (less than 2.5 μm aerodynamic diameter) particles proved substantially more toxic than coarse (larger than 2.5 μm aerodynamic diameter) particles. Dose-response experiments measuring the toxic effects of the transition metals zinc, vanadium and iron revealed that zinc was the most toxic; a concentration of 0.6 mM caused a 50% drop in cellular metabolism, compared to 3 mM and 4 mM for vanadium and iron respectively.
2

Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr -/- expostos as partículas ambientais concentradas sobre o sistema pulmonar / Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr expostos a partículas ambientais concentradas sobre o sistema pulmonar

Alemany, Adair Aparecida Santos 27 June 2013 (has links)
Introdução: Os dados epidemiológicos e experimentais têm mostrado efeitos adversos da exposição pré e pós natal ao material particulado (MP2,5) sobre a saúde fetal e adulto. Entretanto, poucos estudos abordaram a toxicidade fetal da exposição gestacional à poluição do ar ambiental, bem como efeitos a longo prazo de adversos da exposição pré-natal sobre o desenvolvimento pós-natal e maturação de vários sistemas de órgãos. Objetivos: O objetivo deste estudo foi determinar se a exposição pré-natal e / ou pós-natal ao material particulado, influencia o desenvolvimento pulmonar e resposta vascular pulmonar em um modelo de camundongo suscetível a aterosclerose (LDLr-/- camundongos knockout). Métodos: Camundongos LDLr-/- foram expostos durante a gestação ao ar filtrado (AF) ou ar poluído (AC). Após o período de desmame, os filhotes foram subdivididos e novos quatro grupos foram formados de acordo com a exposição gestacional ou a exposição pós natal contínua no ar poluído. Atingindo a idade de 3 meses, esses grupos foram novamente subdivididos, formando um total de 8 grupos e uma dieta hipercolesterolêmica foi introduzida. Os seguintes parâmetros foram analisados: desfechos gestacionais, dosagem de colesterol total (CT) e triglicerídeos (TG) do fígado, avaliação de citocinas no LBA, e avaliação imunohistoquímica da resposta vascular pulmonar . Resultados: Nos grupos que receberam dieta hipercolesterolêmica (DH) os níveis de colesterol apresentaram-se aumentados (p=0,002); A expressão da IL6 no LBA mostrou-se elevada (p=0,01) somente no grupo que não foi exposto a poluição em nunhum período da vida e recebeu dieta postnatalmente. Diferenças significativas também foram observadas na expressão pulmonar vascular dos seguintes imunomarcadores: endotelina (p=0,05); ENOS (p=0,04); IL1? (p=0,005); INOS (p=0,002); ISOP (p=0,001); NOX2 (0,01) e ICAM (0,04) quando comparados ao grupo controle. O volume pulmonar total também se mostra alterado em decorrência do tratamento. Assim, conclui-se que a resposta do desenvolvimento pulmonar à exposição gestacional à poluição particulada do ar pode ser evidenciada mais tarde durante a vida adulta e agir como um fator modulador de insultos pós-natal devido à exposição a poluição do ar e a uma dieta hipercolesterolemica em individuos predispostos aterosclerose / Epidemiological and experimental data have shown adverse effects of gestational and post natal exposure to ambient particulate matter (PM) on the fetal and adult health. However, few studies addressed the fetal toxicity of gestational exposure to environmental air pollution as well as long-term adverse consequences of prenatal exposure on postnatal development and maturation of several organ systems. The aim of this study was to determine if prenatal and/or postnatal exposure to concentrated ambient particles influences lung development and pulmonary vascular response in an atherosclerosis susceptible mouse model (LDLr-/- knockout mice). LDLr-/- mice were exposed during the pregnancy to either filter (AF) or polluted air (CAP). After weaning period, pups were subdivided and new 4 groups formed according to gestational and continuous or not post natal exposure to air pollution. Reaching the age of 3 months these groups were again subdivided and a hypercholesterolemic (HC) diet introduced and a total of 8 groups were formed. Then the following parameters were analyzed: evaluation of the offspring outcomes, assessment of airway responsiveness, evaluation of cytokines in BALF, dosage of total cholesterol (TC) and triglycerides (TG) in the liver and pulmonary vascular response by immunohistochemistry. Results: Animals that received HC diet presented higher levels of cholesterol (p=0.002) when compared to those animals that received normal diet. Expression of IL-6 was only increased in the groups of mice exposed not exposed to particulate air pollution and that received the HC diet (p=0.01). Significant differences were also observed in vascular expression of immunomarkers in the lung endothelin (p=0.05); ENOS (p=0.04); IL1? (p=0.005); INOS (p=0.002); ISOP (p=0.001); NOX2 (0.01) e ICAM (0.04). Total lung volume was also different, there was an increase in those animals receiving a HC diet. In conclusion, the response of the lung development to gestational exposure to particulate air pollution can be evidenced later in life and act as a modulator factor for postnatal insults due to exposures to particulate air pollution and hypercholesterolemic diet in individual predisposed to atherosclerosis
3

Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr -/- expostos as partículas ambientais concentradas sobre o sistema pulmonar / Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr expostos a partículas ambientais concentradas sobre o sistema pulmonar

Adair Aparecida Santos Alemany 27 June 2013 (has links)
Introdução: Os dados epidemiológicos e experimentais têm mostrado efeitos adversos da exposição pré e pós natal ao material particulado (MP2,5) sobre a saúde fetal e adulto. Entretanto, poucos estudos abordaram a toxicidade fetal da exposição gestacional à poluição do ar ambiental, bem como efeitos a longo prazo de adversos da exposição pré-natal sobre o desenvolvimento pós-natal e maturação de vários sistemas de órgãos. Objetivos: O objetivo deste estudo foi determinar se a exposição pré-natal e / ou pós-natal ao material particulado, influencia o desenvolvimento pulmonar e resposta vascular pulmonar em um modelo de camundongo suscetível a aterosclerose (LDLr-/- camundongos knockout). Métodos: Camundongos LDLr-/- foram expostos durante a gestação ao ar filtrado (AF) ou ar poluído (AC). Após o período de desmame, os filhotes foram subdivididos e novos quatro grupos foram formados de acordo com a exposição gestacional ou a exposição pós natal contínua no ar poluído. Atingindo a idade de 3 meses, esses grupos foram novamente subdivididos, formando um total de 8 grupos e uma dieta hipercolesterolêmica foi introduzida. Os seguintes parâmetros foram analisados: desfechos gestacionais, dosagem de colesterol total (CT) e triglicerídeos (TG) do fígado, avaliação de citocinas no LBA, e avaliação imunohistoquímica da resposta vascular pulmonar . Resultados: Nos grupos que receberam dieta hipercolesterolêmica (DH) os níveis de colesterol apresentaram-se aumentados (p=0,002); A expressão da IL6 no LBA mostrou-se elevada (p=0,01) somente no grupo que não foi exposto a poluição em nunhum período da vida e recebeu dieta postnatalmente. Diferenças significativas também foram observadas na expressão pulmonar vascular dos seguintes imunomarcadores: endotelina (p=0,05); ENOS (p=0,04); IL1? (p=0,005); INOS (p=0,002); ISOP (p=0,001); NOX2 (0,01) e ICAM (0,04) quando comparados ao grupo controle. O volume pulmonar total também se mostra alterado em decorrência do tratamento. Assim, conclui-se que a resposta do desenvolvimento pulmonar à exposição gestacional à poluição particulada do ar pode ser evidenciada mais tarde durante a vida adulta e agir como um fator modulador de insultos pós-natal devido à exposição a poluição do ar e a uma dieta hipercolesterolemica em individuos predispostos aterosclerose / Epidemiological and experimental data have shown adverse effects of gestational and post natal exposure to ambient particulate matter (PM) on the fetal and adult health. However, few studies addressed the fetal toxicity of gestational exposure to environmental air pollution as well as long-term adverse consequences of prenatal exposure on postnatal development and maturation of several organ systems. The aim of this study was to determine if prenatal and/or postnatal exposure to concentrated ambient particles influences lung development and pulmonary vascular response in an atherosclerosis susceptible mouse model (LDLr-/- knockout mice). LDLr-/- mice were exposed during the pregnancy to either filter (AF) or polluted air (CAP). After weaning period, pups were subdivided and new 4 groups formed according to gestational and continuous or not post natal exposure to air pollution. Reaching the age of 3 months these groups were again subdivided and a hypercholesterolemic (HC) diet introduced and a total of 8 groups were formed. Then the following parameters were analyzed: evaluation of the offspring outcomes, assessment of airway responsiveness, evaluation of cytokines in BALF, dosage of total cholesterol (TC) and triglycerides (TG) in the liver and pulmonary vascular response by immunohistochemistry. Results: Animals that received HC diet presented higher levels of cholesterol (p=0.002) when compared to those animals that received normal diet. Expression of IL-6 was only increased in the groups of mice exposed not exposed to particulate air pollution and that received the HC diet (p=0.01). Significant differences were also observed in vascular expression of immunomarkers in the lung endothelin (p=0.05); ENOS (p=0.04); IL1? (p=0.005); INOS (p=0.002); ISOP (p=0.001); NOX2 (0.01) e ICAM (0.04). Total lung volume was also different, there was an increase in those animals receiving a HC diet. In conclusion, the response of the lung development to gestational exposure to particulate air pollution can be evidenced later in life and act as a modulator factor for postnatal insults due to exposures to particulate air pollution and hypercholesterolemic diet in individual predisposed to atherosclerosis

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