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Caracterização química e biológica das partículas respiráveis (PM10) do material particulado atmosférico coletado em um sítio urbano da cidade de São Paulo / Chemical and biological characterization of the respirable particles (PM10) of atmospheric particulate matter collected in an urban site of the city of São PauloMartinis, Bruno Spinosa de 03 November 1997 (has links)
A região metropolitana de São Paulo apresenta um intenso e desordenado processo de urbanização e industrialização. Devido a estes processos, a região sofre grandes problemas de poluição atmosférica, agravados em certos meses devido às dificuldades de dispersão dos poluentes. Estes poluentes causam efeitos indesejáveis ao meio ambiente e à saúde humana. A caracterização química e a avaliação da atividade mutagênica desses compostos presentes no material particulado atmosférico (MPA) é um grande desafio analítico e, é de extrema importância para o conhecimento das possíveis correlações entre os poluentes, os efeitos deletérios à saude e as fontes de emissão. Os objetivos deste trabalho foram caracterizar quimicamente os extratos orgânicos polares e semi-polares do material particulado atmosférico da cidade de São Paulo e avaliar sua atividade mutagênica. O MPA é uma mistura complexa de compostos orgânicos e inorgânicos presentes em diferentes faixas de concentrações. Devido a esta complexidade, o fracionamento químico do extrato orgânico deste material é necessário para isolar classes de compostos ou compostos individuais, permitindo a identificação e quantificação dos mesmos. Os resultados obtidos pelas diversas técnicas analíticas empregadas mostraram que os extratos em diclorometano e acetona contém inúmeros compostos orgânicos pertencentes a diferentes classes, tais como hidrocarbonetos policíclicos aromáticos, quinolinas, cetonas, piridinas, furanos, aldeídos, amidas e aminas, sendo que alguns destes compostos são considerados agentes genotóxicos. O extrato em DCM contem a maior massa e sua composição é quase exclusivamente orgânica. Já o extrato em ACE contem além dos orgânicos, espécies inorgânicas. Testes de mutagenicidade indicaram que o MPA coletado na cidade de São Paulo apresenta uma atividade mutagênica relativamente alta quando comparada a outros centros urbanos. / São Paulo metropolitan area presents an intense and chaotic process of urbanization and industrialization. Due to this processes, this region has big atmospheric pollution problem. In certain months of the year, this problem gets worse due to the unfavorable dispersion conditions. The pollutants cause undesirable effects to the environment and to the human health. The chemical characterization and the mutagenic activity evaluation of the compounds present on the atmospheric particulate matter APM) represents an analytical challenge and it is very important for understanding of the correlation among pollutants, health hazards and emission sources. The goal of this work was chemically characterize the polar and moderately polar organic extracts from the APM collected in São Paulo city and to evaluate their mutagenic activity. The APM is a complex mixture of organic and inorganic compounds present in large range of concentration. Due to this complexity, the chemical fractionation of these organic extracts is necessary to isolate classes or individual compounds, to allow their identification and quantification. The results obtained using different analytical techniques demonstrated that the dichlorometane and acetone extracts has several organic compounds belonging to different classes, such as, polycyclic aromatic hydrocarbons, quinolines, ketones, pyridines, furanes, aldehydes, amides and amines. Some of these compoundsa are considered carcinogens and/or mutagens. The dichloromethane extract presented the highest mass yield and its composition is almost exclusively organic. The acetone extract has organic and inorganic species. Mutagenicity tests revealed that the APM from São Paulo city presented a have relatively high mutagenic activity when compared to other urban regions.
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Toxicidade de oxigênio em portadores de porfiria aguda intermitente e em indivíduos expostos a altos níveis de poluição / Oxygen toxicity in patients with acute intermittent porphyria and in individuals exposed to high levels of pollutionMedeiros, Marisa Helena Gennari de 30 December 1981 (has links)
A redução univalente de oxigênio molecular nas células produz intermediários altamente reativos tais como o íon radical Superóxido (O-•2), o radical hidroxil (HO•) e o peróxido de hidrogênio (H2O2). Níveis muito altos ou baixos de tais espécies representam séria ameaça ao metabolismo celular. Diferentes estados patológicos têm sido relacionados com níveis anormais destas espécies em eritrócitos e plaquetas. A proteção biológica contra efeitos tóxicos associados com níveis excessivos de espécies ativadas de oxigênio, tem sido atribuída a três enzimas principais presentes em eritrócitos e outras células: superóxido dismutase, catalase e glutationa peroxidase. Neste trabalho, foram feitas dosagens dessas enzimas protetoras em eritrócitos de indivíduos portadores de porfiria aguda intermitente. Esta doença caracteriza-se por um defeito na biossíntese de heme e clinicamente manifesta-se por dor abdominal intensa, paralisia e distúrbios neuropsíquicos. Foram encontrados nos pacientes em crise aguda atividades elevadas de superóxido dismutase e de glutationa peroxidase enquanto que a atividade de catalase permaneceu normal. Tais resultados apontam a possibilidade de que as manifestações clínicas de IAP relacionadas com toxicidade por oxigênio. Estejam Comparou-se também a atividade destas três enzimas em eritrócitos de residentes na cidade de são Paulo com o de moradores de Vila Parisi, conhecida pelo seu altíssimo nível de poluiçao atmosférica. Os níveis de superóxido dismutase e de glutationa peroxidase são bem mais elevados (cerca de 1,5 vezes) nos indivíduos residentes em Vila Parisi. A elevação da concentração intracelular destas enzimas pode ser sua resposta ao aumento da taxa de oxidação da oxihemoglobina, a qual é conhecida fonte de íons superóxido. Estes dados demonstram profundas diferenças no metabolismo de 02 entre esses dois grupos e talvez uma possível adaptação metabólica dos moradores de Vila Parisi aos altos níveis de poluição a que estão expostos. / The univalent reduction of molecular oxygen in cells produces very reactive species such as the superoxide anion (O-•2), the hydroxyl radical (HO•) and hydrogen peroxide (H2O2). Abnormally high or low concentrations of such species may represent a serious threat to the cellular metabolism. Indeed, several disorders have been associated with abnormal levels of these species in erythrocytes and platelets.The biological protection against toxic effects due to excessive levels of activated species of molecular oxygen has been attributed mainly to three enzymes occurring in erythrocytes and other cells: superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase. In the present work, we report the activities of SOD, GSH-Px and catalase in the erythrocytes of patients with intermittent acute porphyria (IAP), an inborn error in the heme biosynthetic pathway. The clinical manifestations of IAP include abdominal pain and neuropsychiatric symptons. In patients undergoing acute attack, we found increased levels of SOD and GSH-Px, while that of catalase remains unchanged. These results point to the possibility that the clinical manifestations of IAP are related to oxygen toxicity. We have also compared the activities of these enzymes in residents of the city of são Paulo (Brazil) and in subjects living in Vila Parisi (Cubatão, SP, Brazil), a village submitted to high levels of atmospheric pollution. The erythrocyte SOD and GSH-Px levels were found to be ca. 1.5 fold higher in residents of Vila Parisi. These high intracellular enzyme concentrations may reflect a biological defense against an increase in the rate of oxyhemoglobin oxidation, known to be a source of superoxide species. Our results point to important differences between the two populations with respect to the metabolism of oxygen and, perhaps, a metabolic adaptation in the residents of Vila Parisi to the dramatically high levels of atmospheric pollution.
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Avaliação dos efeitos do material particulado proveniente da queima da plantação de cana-de-açúcar sobre a morbidade respiratória na população de Araraquara - SP. / Evaluation of the effects of particulate matter deriving from sugar cane plantation burning on the respiratory morbidity of the Araraquara city population.Arbex, Marcos Abdo 10 May 2002 (has links)
Desde o início do século passado, estudos na literatura médica documentaram uma significativa associação entre poluição atmosférica decorrente da emissão de combustíveis fósseis e morbimortalidade na raça humana, inclusive para níveis de poluentes no ar considerado como seguro para a saúde da população exposta. Na década de 70, durante a crise do petróleo o governo brasileiro implementou um programa chamado Proálcool com o objetivo de produzir um combustível alternativo, renovável, e não poluente: o etanol, derivado da cana-de-açúcar. Esse programa culminou com uma grande produção de veículos movidos a álcool a partir da década de 80, e um grande incremento da cultura da cana-de-açúcar na região central do Estado de São Paulo. Com a crescente utilização do álcool como combustível em veículos automotores houve uma melhora na qualidade do ar nos grandes centros urbanos. Existe, porém, o contraponto: a cana-de-açúcar é uma cultura agrícola singular, uma vez que, por razões de produtividade e de segurança, a colheita é realizada após a queima dos canaviais, o que gera uma grande quantidade de elemento particulado negro denominado "fuligem da cana". Esse material particulado modifica as características do meio ambiente nas regiões onde a cana-de-açúcar é cultivada, colhida e industrializada. A queima da biomassa é a maior fonte de emissão de material particulado e de gases tóxicos no planeta, e não havia na literatura médica qualquer trabalho, que relacionasse a poluição atmosférica em conseqüência da queima desse tipo especifico de biomassa, com a saúde humana. Esse estudo epidemiológico de séries temporais avalia a associação entre o material particulado coletado durante a queima de plantações de cana-de-açúcar e um indicador de morbidade respiratória em Araraquara (SP). Entre 26 de maio e 31 de agosto de 1995, o número diário de pacientes que necessitaram inalações em um dos principais hospitais da cidade foi quantificado, e utilizado para estimar a morbidade respiratória. Para estimar o nível da poluição do ar foi quantificado diariamente o peso do sedimento do material particulado proveniente da fuligem da cana-de-açúcar, obtido por sedimentação simples, em dois pontos da cidade, um localizado no centro e o segundo na zona rural. A associação entre o peso do sedimento e o número de pacientes que necessitaram de terapia inalatória, foi avaliada pelo modelo aditivo generalizado da regressão de Poisson com controle para sazonalidade, temperatura e dias da semana. Encontrou-se uma associação positiva significante e dose dependente entre o número de terapia inalatória e o peso do sedimento. Um aumento de 10 mg no peso do sedimento está associado a um risco relativo de terapêutica inalatória de 1,09 (1-1,19). Nos dias mais poluídos o risco relativo de terapêutica inalatória é de 1,20 (1,03-1,39). Esses resultados indicam que a queima das plantações da cana-de-açúcar pode causar efeitos deletérios à saúde da população exposta. / This times series epidemiological study was designed to evaluate the association between particulate matter collected during sugar cane plantation burning and an indicator of morbidity respiratory in Araraquara, São Paulo State, Brazil. From May 26th to August 31st, 1995, the daily number of patients that received inhalation therapy in one of the main hospitals of the city was recorded and used as a morbidity respiratory estimation. In order to estimate air pollution levels the daily sediment weight from sugar cane particulate matter was measured after collected by simple sedimentation process, in two strategic points of the city: one in a central area and the other in a peripheral area. The association between the sediment weight and the number of patients who received inhalation therapy was evaluated by means of generalized additive Poisson regression models controlled for seasonality, temperature and days of the week. A positive significant and dose-dependent relationship was found between the number of inhalation therapy and the sediment weight. The relative risk of inhalation therapy associated with an increase of 10 mg in the sediment weight was 1.09 (1 - 1.19), and the relative risk of an inhalation therapy was 1.20 (1.03 -1.39) in the most polluted days. These results indicate that sugar cane plantations burning may cause deleterious health effects in the exposed population.
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Alterações eletrocardiográficas, hematológicas e histológicas induzidas pelo material particulado fino na cidade de São Paulo / Electrocardiographic, hematological and histological alterations induced by fine particulate matter of Sao Paulo cityRivero, Dolores Helena Rodriguez Ferreira 22 July 2005 (has links)
Os mecanismos envolvidos na associação entre poluição do ar e aumento da mortalidade cardiovascular não estão ao todo esclarecidos. O objetivo deste estudo foi testar os efeitos agudos do PM2.5 da cidade de São Paulo sobre a freqüência cardíaca (FC), variabilidade da freqüência cardíaca (VFC), inflamação sistêmica e vasoconstrição de arteríolas de ratos Wistar saudáveis. O PM2.5 foi coletado em filtros de fibra de vidro utilizando um amostrador de grandes volumes. Para o ECG foram utilizados 47 ratos que foram submetidos a instilação traqueal de: salina, filtro branco, 50 ?g e 100 ?g de PM2.5. A freqüência cardíaca (FC) e o desvio-padrão dos intervalos NN (SDNN) foram avaliados na fase pré, 30 e 60 minutos após a instilação. Outro grupo de 38 ratos foram submetidos a instilação traqueal de: filtro branco, 100 ?g e 500 ?g de PM2.5 para análises hematológicas e histopatológicas. Estes animais foram sacrificados 24 horas após a instilação traqueal para a coleta de sangue e amostras de pulmão e coração para a morfometria e análise da razão peso seco/úmido. A FC diminuiu significativamente (p<0.001) com o tempo, mas não houve efeito de tratamento ou interação entre tempo e tratamento. O SDNN diminuiu 60 minutos após a instilação nos grupos de 50 ?g e 100 ?g de PM2.5 (p=0.025). O número de reticulócitos aumentou significativamente em ambas as doses de PM2.5 (p<0.05), enquanto que o hematócrito aumentou somente no grupo de 500 ?g (p<0.05). Segmentados, neutrófilos e fibrinogênio diminuíram significativamente, enquanto que os linfócitos aumentaram com 100 ?g de PM2.5 (p<0.05). Houve uma diminuição dose-dependente da razão luz/parede (L/P) das arteríolas pulmonares intra-acinares em ambos grupos de PM (p<0.001). A razão L/P das arteríolas peri-bronquiolares diminuiu no grupo que recebeu 500 ?g de PM2.5 (p<0.001). Houve um aumento significativo da razão peso seco/úmido no coração para o grupo que recebeu 500 ?g (p<0.001). Concluindo, as partículas finas da cidade de São Paulo induzem a uma redução do SDNN e promovem alterações histológicas pulmonares e cardíacas, resultando em significante vasoconstrição. A medula óssea também participou na resposta aguda promovida pelas partículas que alcançam os pulmões / The mechanisms involved in the association between air pollution and increased cardiovascular mortality are not fully understood. The objective of this study was to test the acute effects of Sao Paulo PM2.5 on heart rate, heart rate variability, systemic inflammation and vasoconstriction of arterioles of healthy Wistar rats. PM2.5 was collected in glass fiber filters using a high volume sampler. Forty-seven rats were submitted to tracheal instillation with: saline, blank filter, 50 ?g and 100 ?g of PM2.5 to ECG analysis. Heart rate (HR) and standard deviation of the intervals between normal beats (SDNN) were assessed immediately before, 30 and 60 minutes after instillation. Another thirty-eight rats were submitted to tracheal instillation with: blank filter, 100 ?g and 500 ?g of PM2.5 to hematological and histopathological analysis. These animals were sacrificed 24 hours after instillation when blood, heart and lung samples were collected for morphological and wet-to-dry weight ratio analysis. HR decreased significantly (p< 0.001) with time, but no significant effect of treatment or interaction between time and treatment was observed. SDNN decreased 60 minutes after instillation in groups PM2.5 50 ?g and 100 ?g (p=0.025). Reticulocytes significantly increased at both PM2.5 doses (p<0.05) while hematocrit levels increased in the 500 ?g group (p<0.05). Segmented, neutrophils and fibrinogen levels significantly decreased, while lymphocytes increaseded with 100 ?g of PM2.5 (p<0.05). A significant dose-dependent decrease of intra-acinar pulmonary arterioles Lumen/Wall ratio (L/W) was observed in PM groups (p<0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500?g group (p<0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 ?g group (p<0.001). In conclusion, fine particles in the city of Sao Paulo induces a reduction of SDNN and promote pulmonary and cardiac histological alterations, resulting in significant vasoconstriction. In addition, we observed that the bone marrow also participated in the acute response to particles reaching the lungs
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Participação do Nrf2 no processo de autofagia de células de brônquios humanos expostas ao material particulado de diesel / Participation of Nrf2 in the autophagy process of human bronchial cells exposed to diesel particulate matterDaniela Perroni Frias 10 December 2018 (has links)
As partículas eliminadas na exaustão do diesel (DEP) são importantes fontes diárias de partículas inaladas, responsáveis por gerar espécies reativas de oxigênio no sistema respiratório, fazendo com que as células ativem mecanismos de defesa, como o sistema Keap1-Nrf2 e a autofagia. Para investigar o papel do Nrf2 no processo de autofagia induzida pelas DEPs, BEAS-2B foram expostas às DEP, coletadas diretamente de um motor a diesel. BEAS-2B foram tratadas com sulforafano, bafilomicina e EBSS para testar a relação entre as vias autofágica e antioxidante. A quantidade relativa de mRNA foi verificada por RT-PCR para os seguintes genes: Nrf2, NQO1, HO-1, p62, Atg5 e LCB3. A seguir, BEAS-2B foram transfectadas com RNA silenciador (siRNA) para Nrf2, expostas ou não às DEPs (10 e 50 micro g/mL por 1h e 2 h), e mRNA detectado por RT-PCR e Western blot para proteínas. Bafilomicina (inibidor de autofagia) mostrou uma diminuição significativa nos marcadores antioxidantes Nrf2 (p = 0,024), HO-1 (p = 0,002) e NQO1 (p = 0,003), enquanto sulforafano (ativador de Nrf2) aumentou os marcadores autofágicos LC3B (p = 0,004) e Atg5 (p = 0,007). BEAS-2B expostas às DEP na concentração de 50 micro g/mL por 2hs mostraram um aumento significativo nos genes autofágicos LC3B (p = 0,018) e p62 (p = 0,007) e nos genes da via antioxidante Nrf2 (p = 0,007) e NQO1 (p = 0,025). Houve uma diminuição significativa no mRNA de LC3B (p < 0,001), p62 (p = 0,001) e Atg5 (p = 0,024) nas células transfectadas com siRNA, expostas ou não à DEP. Western blotting mostrou uma redução das proteínas Nrf2, p62 e LC3II nas BEAS-2B siRNA, indicando que a exposição ao silenciamento de Nrf2 modificou a expressão de marcadores de autofagia (R < 1). Os resultados deste estudo mostram que, em células brônquicas expostas às DEP, o sistema Nrf2 e a autofagia trabalham em conjunto para tentar manter a homeostase celular / Diesel Exhaust Particles (DEPs) are main sources of daily inhaled particles, responsible for generating reactive oxygen species in the respiratory system, and causing the cells to activate defense mechanisms, such as the Keap1-Nrf2 system and autophagy. In order to investigate the role of Nrf2 in Dep-induced autophagy, BEAS-2B cells collected directly from a diesel engine were exposed to DEP and treated with sulforaphane, bafilomycin and BESS to test the relationship between autophagic and antioxidant pathways. The relative amount of mRNA was verified by RT-PCR for the following genes: Nrf2, NQO1, HO-1, p62, Atg5 and LCB3. Next, BEAS-2B cells were transfected with silencer RNA (siRNA) specific to Nrf2, exposed or not to DEPs (10 and 50 micro g/mL 1h and 2hs), and mRNA detected by RT-PCR and Western blotting for protein. Bafilomycin ( autophagy inhibitor) showed a significant decrease in the antioxidant markers Nrf2 (p=0.024), HO-1 (p = 0.002) and NQO1 (p = 0.003), whereas sulforaphane (Nrf2 activator) increased the expression levels of autophagic markers LC3B (p=0.004) and Atg5 (p=0.007). BEAS-2B exposed to DEP at a concentration of 50 micro g/mL for 2hs showed a significant increase in autophagic genes LC3B (p=0.018) and p62 (p=0.007),and in the antioxidant pathway markers Nrf2 (p=0.007) and NQO1 (p=0.025). There was a significant decrease in mRNA of the LC3B (p < 0.001), p62 (p=0.001) and Atg5 (p=0.024) in cells transfected with siRNA, exposed or not to DEP. Western blotting showed a reduction of Nrf2, p62 and LC3II proteins in BEAS-2B transfected with siRNA, indicating that Nrf2 silencedexposed to DEP modulated the expression of autophagy markers (R < 1). The results of this study show that, in bronchial cells exposed to DEP, the Nrf2 system and autophagy work together in order to try to maintain cellular homeostasis
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Décomposition tensorielle de signaux luminescents émis par des biosenseurs bactériens pour l'identification de Systèmes Métaux-Bactéries / Tensor decomposition approach for identifying bacteria-metals systemsCaland, Fabrice 17 September 2013 (has links)
La disponibilité et la persistance à l'échelle locale des métaux lourds pourraient être critiques notamment pour l'usage futur des zones agricoles ou urbaines, au droit desquelles de nombreux sites industriels se sont installés dans le passé. La gestion de ces situations environnementales complexes nécessitent le développement de nouvelles méthodes d'analyse peu invasives (capteurs environnementaux), comme celles utilisant des biosenseurs bactériens, afin d'identifier et d'évaluer directement l'effet biologique et la disponibilité chimique des métaux. Ainsi dans ce travail de thèse, nous avons cherché à identifier, à l'aide d'outils mathématiques de l'algèbre multilinéaire, les réponses de senseurs bactériens fluorescents dans des conditions environnementales variées, qu'il s'agisse d'un stress engendré par la présence à forte dose d'un métal ou d'une carence nutritive engendrée par son absence. Cette identification est fondée sur l'analyse quantitative à l'échelle d'une population bactérienne de signaux multidimensionnels. Elle repose en particulier sur (i) l'acquisition de données spectrales (fluorescence) multi-variées sur des suspensions de biosenseurs multicolores interagissant avec des métaux et sur (ii) le développement d'algorithme de décomposition tensoriels. Les méthodes proposées, développées et utilisées dans ce travail s'efforcent d'identifier « sans a priori» a minima, la réponse fonctionnelle de biosenseurs sous différentes conditions environnementales, par des méthodes de décomposition de tenseurs sous contraintes des signaux spectraux observables. Elles tirent parti de la variabilité des réponses systémiques et permettent de déterminer les sources élémentaires identifiant le système et leur comportement en fonction des paramètres extérieurs. Elles sont inspirées des méthodes CP et PARALIND . L'avantage de ce type d'approche, par rapport aux approches classiques, est l'identification unique des réponses des biosenseurs sous de faibles contraintes. Le travail a consisté à développer des algorithmes efficaces de séparations de sources pour les signaux fluorescents émis par des senseurs bactériens, garantissant la séparabilité des sources fluorescentes et l'unicité de la décomposition. Le point original de la thèse est la prise en compte des contraintes liées à la physique des phénomènes analysés telles que (i) la parcimonie des coefficients de mélange ou la positivité des signaux source, afin de réduire au maximum l'usage d'a priori ou (ii) la détermination non empirique de l'ordre de la décomposition (nombre de sources). Cette posture a permis aussi d'améliorer l'identification en optimisant les mesures physiques par l'utilisation de spectres synchrones ou en apportant une diversité suffisante aux plans d'expériences. L'usage des spectres synchrones s'est avéré déterminant à la fois pour améliorer la séparation des sources de fluorescence, mais aussi pour augmenter le rapport signal sur bruit des biosenseurs les plus faibles. Cette méthode d'analyse spectrale originale permet d'élargir fortement la gamme chromatique des biosenseurs fluorescents multicolores utilisables simultanément. Enfin, une nouvelle méthode d'estimation de la concentration de polluants métalliques présents dans un échantillon à partir de la réponse spectrale d'un mélange de biosenseurs non-spécifiques a été développée / Availability and persistence of heavy metals could be critical for future use of agricultural or urban areas, on which many industrial sites have installed in the past. The management of these complex environmental situations requiring the development of new analytical methods minimally invasive, such as bacterial biosensors, to identify and directly assess the biological effects and the chemical availability of metals. The aims of this thesis was to identify the responses of fluorescent bacterial sensors various environmental conditions, using mathematical tools of algebra multi-linear, whether stress caused by the presence of high dose of a metal or a nutrient deficiency caused by his absence. This identification is based on quantitative analysis of multidimensional signals at the bacterial population-scale. It is based in particular on (i) the acquisition of multivariate spectral data on suspensions of multicolored biosensors interacting with metals and (ii) the development of algorithms for tensor decomposition. The proposed methods, developed and used in this study attempt to identify functional response of biosensors without \textsl{a priori} by decomposition of tensor containing the spectral signals. These methods take advantage of the variability of systemic responses and allow to determine the basic sources identifying the system and their behavior to external factors. They are inspired by the CP and PARALIND methods. The advantage of this approach, compared to conventional approaches, is the unique identification of the responses of biosensors at low constraints. The work was to develop efficient algorithms for the source separation of fluorescent signals emitted by bacterial sensors, ensuring the sources separability and the uniqueness of the decomposition. The original point of this thesis is the consideration of the physical constraints of analyzed phenomena such as (i) the sparsity of mixing coefficients or positivity of sources signals in order to minimize the use of a priori or (ii) the non-empirical determination of the order of decomposition (number of sources).This posture has also improved the identification optimizing physical measurements by the use of synchronous spectra or providing sufficient diversity in design of experiments. The use of synchronous spectra proved crucial both to improve the separation of fluorescent sources, but also to increase the signal to noise ratio of the lowest biosensors. This original method of spectral analysis can greatly expand the color range of multicolored fluorescent biosensors used simultaneously. Finally, a new method of estimating the concentration of metal pollutants present in a sample from the spectral response of a mixture of non-specific biosensor was developed
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Molecular genetic studies of pollutant response in the European flounder, Platichthys flesus (L.)Dixon, Thomas James January 2003 (has links)
Effects of man made pollutants on an ecosystem are initiated at the cellular level where a prime determinant for survival of an organism is its ability to metabolise and excrete toxic chemicals or their metabolites, thereby preventing cellular toxicity or damage to germ cell DNA. Cytochrome P450 (CYP) enzymes are responsible (in concert with the remainder of the Ah battery enzymes) for the metabolism of numerous xenobiotics and endogenous compounds, including the metabolic activation of most environmental toxic chemicals and carcinogens. Genetic polymorphisms which affect performance of these enzymatic detoxification systems may alter tolerance to pollutants and thus survival in polluted environments. Alterations in the susceptibility of individuals and the development of resistant populations has arisen by forced selection of populations with variant genes, resulting in increased detoxification capacity. There is evidence for such scenarios of variations in activities of pollutant biotransforming enzymes of fish contributing to survival in polluted estuarine environments and several chemically resistant populations have been identified in the USA and Europe. In fish it has been demonstrated that CYP1A enzyme activity is required to activate some carcinogenic xenobiotics to a metabolic state in which they can form DNA adducts. The mechanism of reduced CYP1A expression in highly contaminated populations may therefore represent resistance to chemical stressors. European flounder (Platichthys flesus) from some waterways which have a long history of severe sedimentary contamination do not show elevated levels of CYP1A. The aim of the current study was to investigate whether any heritable differences were apparent between offspring from parents inhabiting long-term polluted and pristine areas. Flounder were obtained from a highly polluted estuary in the UK and crossed with fish from a relatively pristine environment. Offspring were raised in communal tanks in order to standardise environmental conditions, and allow investigations into the genetic variation of CYP1A. To allow identification of offspring to parental fish, polymorphic microsatellite loci were isolated and characterised for the flounder. Novel cDNA probes to transcription factors in the detoxification pathway (AhR2 and ARNT2) were cloned for flounder, and RT-PCR / Southern blot methods were developed for quantitation of gene transcript levels. A novel method of CYP1A quantification using real-time PCR was developed. PAH and PCB exposure trials were carried out on mixed batch offspring, and CYP1A gene transcript levels assessed using Northern blot and real-time PCR techniques. Offspring were genotyped to their parents using the microsatellites obtained, and CYP1A transcript levels were correlated with clean and polluted areas. CYP1A was further correlated to transcription factor expression, and data are presented. Following exposure to the commercial PCB mixture, Aroclor 1254, CYP1A transcript levels were found to be significantly lower in families whose parents originated from a polluted area. This observation indicates that there is a possible genetic component to variation in CYP1A levels, and that these fish may have acquired a heritable tolerance to polluted areas. The lack of induction, or correlation with CYP1A levels, of AhR2 and ARNT2 expression indicates a possible AhR independent pathway for the metabolism of PCBs in the flounder. © Tom Dixon 2003 http://www.tomdixon.org
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Comparison Of The Rural Atmosphere Aerosol Compositions At Different Parts Of TurkeyDogan, Guray 01 January 2005 (has links) (PDF)
Long term data generated at four rural stations are compared to determine similarities and differences in aerosol compositions and factors contributing to observed differences at different regions in Turkey. The stations used in this study are located at Mediterranean coast (20 km to the west of Antalya city), Black Sea coast (20 km to the east of Amasra town), Central Anatolia (Ç / ubuk, Ankara) and Northeastern part of the Anatolian Plateau (at Mt. Uludag). Data used in comparisons were generated in previous studies. However, some re-analysis of data were also performed / (1) to improve the similarities of the parameters compared and (2) to be able to apply recently-developed methodologies to data sets.
Data from Mediterranean and Black Sea stations were identical in terms of parameters measured and were suitable for extensive comparison. However, fewer parameters were measured at Ç / ubuk and Uludag stations, which limited the comparisons involving these two stations. Comparison included levels of major ions and elements, short-term and seasonal variations in concentrations, background (baseline) concentrations of elements, flow climatology of regions, correlations between elements, potential source areas affecting regions, and source types affecting chemical composition of particles.
Comparison of levels of measured parameters in four regions showed that there are some differences in concentrations that arise from differences in the local characteristics of the sampling points. For example very high concentrations of elements such as Na and Cl in the Mediterranean region is attributed to closer proximity of the Antalya station to coast and not a general feature of the Mediterranean aerosol. There are also significant regional differences in the concentrations of measured elements and ions as well. Concentrations of anthropogenic elements are very similar at two coastal stations (Antalya and Amasra), but they are approximately a factor of two smaller at the two stations that are located on the Anatolian Plateau. This difference between coastal and high altitude plateau stations, which is common to all anthropogenic species, is attributed to different source regions and transport mechanisms influencing coastal regions and Anatolian Plateau.
Some statistically significant differences were also observed in the temporal variations of elements and ions measured in different stations. The elements with crustal origin showed similar seasonal pattern at all stations, with higher concentrations in summer and lower concentrations in winter. This difference between summer and winter is attributed to suppression of re-suspension of crustal aerosol from wet or ice-covered surface soil in winter. Concentrations of anthropogenic elements, on the other hand, did not show a statistically significant seasonal trend at Amasra, Ç / ubuk and Uludag stations, but they have higher concentrations during summer months at the Antalya station. This difference between Mediterranean aerosol and aerosol at the Central and Northern Turkey is due to influence of more local sources on Ç / ubuk, Amasra and Uludag stations and domination of more distant source in determining aerosol composition at the Mediterranean region. A similar conclusion of strong influence of local sources on chemical composition of particles at the Central Anatolia was also suggested by the comparison of baseline concentrations in each station.
General features in flow climatology (residence times of upper atmospheric air masses) in each region are found to be similar with more frequent flow from W, WNW, NW and NNW wind sectors. Since these are the sectors that include high emitting countries in Eastern and Western Europe and Russia, transport from these sectors are expected to bring pollution from both distant European countries and more local Balkan countries and western parts of Turkey.
Flow climatology in stations showed small, but statistically significant, differences between summer and winter seasons. These variations suggested that the station at the Central Anatolia and Black Sea (Ç / ubuk Amasra and Uludag stations) are affected from sources located at the Western Europe in winter season and from sources located at the Eastern Europe in summer. Mediterranean aerosol, on the other hand, are affected from sources at the Western Europe and do not show any seasonal differences. This variation in flow climatology between summer and winter seasons (and lack of variation at the Mediterranean station) is supported by the seasonal variation (and lack of variation at the Mediterranean station) in SO42-/NO3- ratio measured at the stations.
Potential source contribution function (PSCF) values are calculated for selected elements and ions in each station. Statistical significance of calculated PSCF values is tested using bootstrapping technique. Results showed that specific grids at Russia and at Balkan countries are common source regions affecting concentrations of anthropogenic elements at all four regions in Turkey. However, each station is also affected from specific source regions as well. Aerosol composition at the Anatolian Plateau are affected from sources closer to the sampling points whereas Mediterranean and Black Sea aerosol are affected from source regions that farther away from the receptors. It should be noted that the same conclusion is also reached in comparison of seasonal patterns and baseline concentrations at these stations.
Types of sources affecting aerosol composition at Black Sea, Mediterranean and Central Anatolia are also compared. Source types affecting atmospheric composition in these regions were calculated using positive matrix factorization (PMF). The results showed that aerosol at the Black Sea, Central Anatolia and Mediterranean atmosphere consists of 8, 6 and 7 components, respectively. Two of these components, namely a crustal component and a long-range transport component are common in all three stations. The chemical compositions of these common components are shown to the same within 95% statistical significance interval. Three factors, namely a fertilizer factor, which is highly enriched in NH4+ ion, a sea salt component and an arsenic factor are common in the Mediterranean and Black Sea aerosol but not observed at the Central Anatolia. Other factors found in the regions are specific for that region.
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Simulating Co2 Sequestration In A Depleted Gas ReservoirOzkilic, Ismet Oke 01 September 2005 (has links) (PDF)
Carbon dioxide is one of the greenhouse gases which have strong impacts on the environment and its amount in the atmosphere is far beyond to be ignored. Carbon dioxide levels are projected to be reduced by sequestering it directly to the underground.
High amounts of carbon dioxide can be safely stored in underground media for very long time periods. Storage in depleted gas reservoirs provides an option for sequestering carbon dioxide.
In 2002, production of Kuzey Marmara gas reservoir has been stopped due to gas storage plans. Carbon dioxide sequestration in Kuzey Marmara field has been considered in this study as an alternative to the gas storage projects.
Reservoir porosity and permeability maps were prepared with the help of Surfer software demo version. These maps were merged with the available Kuzey Marmara production information to create an input file for CMG-GEM simulator and a three dimensional model of the reservoir was created.
History match of the field model was made according to the 1998-2002 production data to verify the similarity between the model and actual reservoir.
Kuzey Marmara field is regarded as a candidate for future gas storage projects. The reservoir still contains producible natural gas. Four different scenarios were prepared by considering this fact with variations in the regional field properties and implemented into previously built simulation model. These scenarios primarily focus on sequestering carbon dioxide while producing as much as natural gas possible.
After analyzing the results from the scenarios it is realized that / CO2 injection can be applied to increase natural gas recovery of Kuzey Marmara field but sequestering high rate CO2 emissions is found out to be inappropriate.
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Associação entre os níveis ambientais de poluição atmosférica e mudanças na razão sexual na cidade de São Paulo: uma abordagem epidemiológica e experimental / Association between ambient levels of air pollution and changes in the sex ratio in the city of \"São Paulo\" an epidemiologic and experimental approachAna Júlia de Faria Coimbra Lichtenfels 10 October 2006 (has links)
Prévios estudos têm demonstrado alterações nas taxas normais de razão sexual. No entanto, uma associação direta entre níveis ambientais de poluição e razão sexual, não tem sido ainda claramente demonstrada. A fim de investigarmos esta associação, desenvolvemos duas abordagens: uma epidemiológica e outra experimental. O efeito da poluição sobre a população da cidade de São Paulo foi verificado através da associação entre a razão sexual e gradientes de concentração de material particulado (PM10). A fim de conferir plausibilidade biológica aos achados epidemiológicos, camundongos machos com 10 dias de vida, foram expostos em câmaras do tipo Topo Aberto, sob condições de exposição mais controladas. Uma associação negativa e significante foi observada entre razão sexual e PM10, dentro de uma faixa estreita de concentração de PM10 (31 a 61 ?g/m3). Na região menos poluída, a razão sexual foi de 51,7% (106,8) para 34.795 nascimentos registrados, enquanto que para a mais poluída, a proporção decresceu para 50,7% (102,9) para 48.023 nascimentos registrados, com uma redução de 1% no número total de nascimentos masculinos. O grupo de camundongos da linhagem Swiss, acasalados com fêmeas virgens, maduras e não expostas, produziu uma prole com alterações significativas (p<0,041) na razão sexual (0,86) quando comparado com o grupo controle (1,34). Análises morfométricas dos testículos demonstraram alterações significativas no perfil da linhagem germinativa, com reduções no número das espermátides alongadas (p<0,020) e no número total de células (p<0,032). Um decréscimo na concentração dos espermatozóides (46,95x106 /ml) também foi observado nos animais expostos à poluição quando comparado ao grupo controle (54,60x106 /ml). A partir dos nossos resultados podemos concluir que a poluição pode interferir com a distribuição do sexo nas populações expostas aos níveis ambientais de poluição. / Some studies have observed abnormal sex ratios in industrial polluted areas but a direct association between urban levels of air pollutant and sex ratio at birth has not hitherto reported. To examine whether this relationship held true, we evaluated how ambient air pollution interferes on female/male ratio in human and mice models. The effect of air pollution was addressed by determining SSR (secondary sex ratio) across pollution gradients in the city of São Paulo, using inhalable particles (PM10) as a proxy variable for overall pollution levels. To provide biological plausibility to the foregoing epidemiological observation, we designed an experimental study exposing mice in controlled chamber conditions. Results disclosed a significant negative between SSR and PM10, within a relatively narrow range of PM10 levels (31 to 61 ?g/m3). In the least polluted area the sex ratio was 51.7% (106.8) for 34,795 births recorded, and for the most polluted area the proportion decreased to 50.7 % (102.9) for 48,023 births recorded, indicating a difference of 1% in total male births. This result corresponds to a 1,180 unborn male offspring in the highest polluted areas. The group of male Swiss mice housed 10 days after birth in open top chambers exposed to air pollution, where they mate mature and non-exposed virgin female mice, produced an offspring with a 0.86 male/female ratio. The offspring of the group of mice concurrently raised in similar but filtered open top chamber was significantly (p<0.042) higher (1.34). A remarkable result was the testicular histological morphometry with a significant (p<0,020) reduction in the number of elongated spermatids and total cells (p<0,032) of exposed males. In association, a decrease in sperm concentration in the caudal portion of the epidydimus was also found in the exposed mice (46,95x106 /ml) compared to the non-exposed (54,60x106 /ml). In conclusion the findings in our study support the concept that ambient air pollution may interfere with sex distribution of exposed populations
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