Le but des travaux de cette thèse a été de mettre en place des protocoles de synthèse et de polymérisation de composés phénoliques. Le premier objectif a été de développer et optimiser des modes opératoires robustes et reproductibles permettant de polymériser de manière contrôlée ces derniers en présence d’oxydases, et particulièrement de laccase. Les études mécanistiques menées dans le cadre de ces nouveaux procédés ont mené à une meilleure compréhension de la réactivité des phénols (oxydation, dismutation) et à de nouveaux modes de valorisation de ces composés. Ainsi, ces procédés nous ont permis d’accéder sélectivement à des composés phénoliques de complexité structurale et fonctionnalité variées (dimères, trimères ou oligomères peu polydisperses) pouvant être utilisés en tant qu’antioxydants ou encore monomères/synthons pour la chimie des polymères. Pour illustrer le potentiel de ces composés phénoliques dans le domaine des polymères, ils ont été mis en jeu dans des réactions de polymérisation par métathèse (ADMET) et polymérisation radicalaire (thiol-ène). / The purpose of this thesis was to develop experimental protocols for the polymerization of phenoliccompounds.The first objective was to develop and optimize robust and reproducible procedures to control thepolymerization of phenolic compounds in the presence of oxidases, such as laccase. Mechanisticstudies were conducted during these new processes in order to have a better understanding of thereactivity of phenols (oxidation, dismutation) and find new ways of valorization of such compounds.Thus, these methods have enabled us to selectively access phenolic compounds of structuralcomplexity and variable functionalities (dimers, trimers or oligomers) that can be used asantioxidants or monomers for the polymer chemistry. To illustrate the potential of these phenoliccompounds in the field of polymers, they have been involved in polymerization reactions such asADMET and radical polymerizations (thiol-ene).

Bisfenóis, filtros UV de benzofenona, parabenos e antimicrobianos como triclocarban são amplamente utilizados em produtos alimentares, farmacêuticos, cosméticos e de cuidados pessoais e também são encontrados como contaminantes. A maioria destes compostos apresentam possíveis efeitos adversos à saúde, principalmente devido ao fato de sua potencial atividade desreguladora endócrina. Neste sentido, é crescente o interesse pelo desenvolvimento de métodos analíticos que sejam mais simples e que possam ter a capacidade de detecção do maior número de analitos possíveis simultaneamente para uso em estudos de biomonitoramento humano. O objetivo deste projeto foi desenvolver um novo método de preparo de amostras em microextração em sorvente empacotado (MEPS, do inglês \"microextraction by packed sorbent\") para a extração simultânea de substâncias potencialmente desreguladoras endócrinas (parabenos, bisfenóis, benzofenonas e triclocarban). Em 250 ?L de urina sintética (pH 5,3) foram adicionados os analitos a uma concentração de 20 ng/mL e diluídos com 250 ?L de água. Após este procedimento, os compostos foram extraídos manualmente da amostra de urina usando MEPS C18 com 5 ciclos de aspirar-dispensar de 100 ?L. A eluição dos analitos foi realizada utilizando 100 ?L (metanol/água 80:20), seguido de análise em LC-MS/MS. O cartucho MEPS, após a limpeza, foi reutilizado para extrações múltiplas sem a presença de efeito de memória. As separações cromatográficas foram conduzidas em uma coluna C18 a 40 °C. A fase móvel foi composta por um gradiente de metanol e água a uma vazão de 500 ?L/min. Os dados foram adquiridos no modo MRM com íons negativos como precursores. O método MEPS-LC-MS/MS proposto apresentou curva de calibração linear para todos os analitos com coeficiente de correlação (r) maior que 0,99 no intervalo do limite inferior de quantificação (LIQ) a 20,0 ng/mL. Os LODs variaram de 0,005-0,1 ng/mL e os LIQ variaram de 0,5-2,5 ng/mL. Além disso, a precisão foi expressa como o coeficiente de variação, onde os valores obtidos foram menores que 20% (n=3) nos LIQ e menores que 15% (n=3) nas concentrações de 10,0 e 20,0 ng/mL. A exatidão foi expressa na forma de erro padrão relativo, onde os valores obtidos não foram superiores a ±20% (n=3) para os LIQ e ±15% (n=3) nas concentrações 10,0 e 20,0 ng/mL. O procedimento MEPS proposto apresentou vantagens que incluem a possibilidade de extração e determinação simultânea de 16 analitos em urina, com redução dos volumes de amostra e solvente utilizados, além de vantagens como tempo reduzido de preparo de amostra, clean up da matriz e dispensa etapa prévia ao preparo de amostra / Bisphenol, benzophenone UV filters, parabens and antimicrobials as triclocarban are widely used in food, pharmaceuticals products, cosmetic and personal care products or they are fond as contaminants. Most of these compounds show possible health adverse effects, mainly due to the fact of its potential endocrine disrupting activity. Thus, there is an increasing interesting in new analytical method development that will be simple and able to detect largest number of analytes possible simultaneously to be used in human biomonitoring studies. The project goal was developed a new sample preparation methody in Microextraction in packed sorbent (MEPS) to simultaneous extraction followed by liquid chromatography coupled to mass spectrometry in tandem analysis (LC-MS/MS) of 16 substances potentially endocrine disrupting (parabens, bisphenols, benzophenones and triclocarban). In 250 ?L of synthetic urine (pH 5.3) were spiked with compounds at a concentration of 20 ng/mL and diluted with 250 ?L of water. After this procedure, the compounds were extracted manually from urine sample using MEPS C18 with 5 draw-eject 100 ?L cycles. The elution was performed using 100 ?L (methanol/water 80:20) followed by LC-MS/MS analysis. The MEPS cartridge, after cleaned, was used for multiple extractions without any carry-over effect. Chromatographic separations were carried out on a C18 column at 40 oC. The Mobile phase was composed by a gradient methanol and water at a flow rate of 500 ?L/min. Data were acquired the MRM mode with negative ions as precursors. The proposed MEPS-LC-MS/MS method showed calibration curve linear to all analytes with correlation coefficient higher than 0,99 in the range from low limit of quantification (LIQ) to 20,0 ng/mL. The LODs range from 0,005-0,1 ng/mL and LIQ range from 0,5 to 2,5 ng/mL. Moreover, the precision was reported as variation coefficient, where the values were less than 20% (n=3) to the LIQ and less than 15% (n=3) to 10,0 and 20,0 ng/mL concentrations. The accuracy was reported as relative standard error, where the values were less than ±20% to the LIQ and less than ±15% (n=3) to 10,0 and 20,0 ng/mL concentrations. The MEPS procedure proposed showed advantages including possibility to extraction and simultaneous determination of 16 analytes in urine, with sample and solvents volume reduction besides it shows advantages as time reducing in sample preparation, matrix clean up and dispense previous sample preparation step.

Resumo: O Bisfenol A (BFA) é um monômero formado por dois anéis fenólicos e empregado na produção de plástico policarbonato e resinas epóxi. O policarbonato é amplamente empregado na fabricação de vários produtos dos meios digitais (CD e DVD), recipientes reusáveis de alimentos e bebidas e muitos outros produtos. As resinas epóxi são usadas em circuitos elétricos, pinturas, adesivos, revestimentos protetores de latas de alimentos e bebidas e complexos dentários para obturações. Estudos revelaram que o BFA age nos organismos vivos com efeitos de desregulação endócrina, como um xenobiótico com ação estrogênica, provocando aumento da incidência de câncer de mama, queda da quantidade de esperma, diminuição da fertilidade, defeitos congênitos secundários à exposição fetal e outras alterações. O BFA chega ao ambiente aquático por inúmeras vias distintas como, por exemplo, vindo do lodo proveniente de esgoto, da descarga de esgotos domésticos e industriais, dos lixões e aterros sanitários não controlados. Neste trabalho, desenvolveu-se e validou-se um método para a determinação de BFA em águas superficiais e de abastecimento à população de Campo Grande - MS, utilizando-se extração em fase sólida EFS (cartuchos de fase polimérica Strata-X), derivação com N O-Bis-(trimetilsilil) trifluroacetamida (BSTFA) e detecção por cromatografia a gás acoplada à espectrometria de massas. A precisão e a exatidão do método foram avaliadas em de ensaios de recuperação. Recuperações variando de 91 a 113% com coeficientes de variação percentuais inferiores a 8,9% foram obtidos com limites de detecção e quantificação do método de 2,4 e 10 ng L-1, respectivamente. Também foi avaliada a conservação do BFA nos próprios cartuchos de EFS onde se observou que este analito pode ser armazenado por até 90 dias sem diferenças significativas entre o valor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Bisphenol A (BPA) is a monomer consisting of two phenolic rings and employed in the production of polycarbonate plastic and epoxy resins. The polycarbonate is widely used in many manufactured products from digital media (CD and DVD), reusable containers food and beverages and many other products. Epoxy resins are used in electrical circuits, paints, adhesives, protective coatings for cans of food, drinks and complex dental fillings. Studies have shown that BPA acts in living organisms with the purpose of endocrine disrupting as a xenobiotic with estrogenic action, causing an increased incidence of breast cancer, decrease the amount sperm, fertility decreased, birth defects secondary to fetal exposure and other changes. BPA reaches the aquatic environment by several distinct pathways, for example, coming from the sludge sewage, discharge of domestic sewage and industrial waste dumps and the landfills. In this work, we developed and validated a method for the determination of BPA in surface water and supply population of Campo Grande - MS was developmente ande validated using solid phase extraction SPE (polymeric phase cartridges Strata-X), derivatized with N-O-Bis (trimethylsilyl) trifluroacetamide (BSTFA) and detection by gas chromatography coupled to mass spectrometry. The precision and accuracy of method were evaluated through recovery experiments. Recoveries ranging from 91-113% with coefficients of variation lower to 8.9% were obtained with limits of detection and quantification of 2.4 and 10 ng L-1, respectively. We also analyzed the estability of BPA in individual cartridges SPE where it was observed that the analyte can be stored for up to 90 days without significant differences between the determined and the value taken as true. The leaching of BPA from PVC pipes was investigated coming to conclusions that this is a source contamination of water by this important endocrine... (Complete abstract click electronic access below) / Orientador: Maria Lucia Ribeiro / Coorientador: Marcia Helena de Rizzo da Matta / Banca: Luciana Polese / Banca: Carolina Lourencetti / Banca: Raquel Fernandes Pupo Nogueira / Banca: Wilson de Figueiredo Jardim / Doutor

Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-06-01T13:46:10Z No. of bitstreams: 1 LIGIA_MARIA_NOGARETT_PIBERNAT_DE_CARVALHO_TES.pdf: 602746 bytes, checksum: 5e6dcc81b20622b739f9ab98624f9a66 (MD5) / Rejected by Sheila Dias (sheila.dias@pucrs.br), reason: Devolvido devido ? falta da capa institucional no arquivo em PDF. on 2018-06-11T12:41:58Z (GMT) / Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2018-06-11T17:29:30Z No. of bitstreams: 1 LIGIA_MARIA_NOGARETT_PIBERNAT_DE_CARVALHO_TES.pdf: 1308142 bytes, checksum: e3ba9abe3c75e3384b12c1a64fbba5dd (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-22T11:52:39Z (GMT) No. of bitstreams: 1 LIGIA_MARIA_NOGARETT_PIBERNAT_DE_CARVALHO_TES.pdf: 1308142 bytes, checksum: e3ba9abe3c75e3384b12c1a64fbba5dd (MD5) / Made available in DSpace on 2018-06-22T12:01:25Z (GMT). No. of bitstreams: 1 LIGIA_MARIA_NOGARETT_PIBERNAT_DE_CARVALHO_TES.pdf: 1308142 bytes, checksum: e3ba9abe3c75e3384b12c1a64fbba5dd (MD5) Previous issue date: 2017-04-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of the present study was to asses the present of Bisphenol A in dental material used on CAD/CAM block.For this In Vitro study, blocks for CAD-CAM, Lava Ultimate, Enamic and Mark II in standardized fragments containeing Bisphenol A were evaluated. Ten fragments of each block were made: n = 30, immersed in deionized water on group 1 and artificial saliva Kin Hidrat on group 2 in a light protected bottle.Stored in a culture stove for 24 hours, all samples were put in 1,5ml bottles containing 1,0ml of artificial saliva (KIN HIDRAT, PharmaKIN, S?o Paulo, Brazil ) on group 1 and deionized water on group 2, and then freezed in -80?C for 24 hours. After the 24 hour period, the samples were submitted to High Efficiency Chromatography on Toxicology and Pharmacology Institute of PUCRS as methodology described on this study.After cromatographic analysis of groups 1 and 2, the non-release of Bisphenol A was observed in all groups of samples tested. All groups and samples presented peak release of unidentified substance of different molecular weight and different breaking time than the Bisphenol A standard. Additional researches using other analysis methods are needed to examine the cumulative estrogenic effects of Bisphenol A dental materials for CAD CAM and composite resins. / O objetivo geral deste estudo foi avaliar o componente Bisfenol A presente em blocos de materiais dent?rios utilizados no sistema CAD/CAM quanto a libera??o ou n?o de Bisfenol A. Foram avaliados para a realiza??o deste estudo in vitro, blocos para CAD/CAM, Lava Ultimate, Enamic e Mark II, em fragmentos padronizados, cuja matriz de resina composta continha Bisfenol A. Foram confeccionados 10 fragmentos de cada um dos blocos: n = 30, imerso em ?gua deionizada no grupo 1 e saliva artificial KinHidrat no grupo 2 em frasco protegido da luz. Armazenadas em estufa por 24hs,todas as amostras, ap?s o periodo de 24hs, foram armazenadas em recipientes de 1,5ml contendo 1,0 ml de saliva artificial (KIN HIDRAT,PharmaKIN, S?o Paulo, Brasil ) no grupo 1 e ?gua deionizada no grupo 2 e ap?s congeladas ? - 80?C por 24hs. Decorrido o per?odo de 24h, as amostras foram submetidas a cromatografia de alta efici?ncia (HPLC) no Instituto de Toxicologia e Farmacologia da PUCRS com metodologia descrita no estudo.Ap?s an?lise cromatogr?fica dos grupos 1 e 2 observou- se a n?o libera??o de Bisfenol A em nenhum dos grupos de amostras testadas.Todos os grupos e amostras apresentaram pico de libera??o de subst?ncia n?o identificada de diferente peso molecular e diferente tempo de quebra do padr?o de Bisfenol A. Pesquisas adicionais, empregando outros m?todos de an?lise s?o necess?rias para examinar os efeitos estrog?nicos cumulativos do Bisfenol A de materiais dent?rios para CAD/CAM e resinas compostas.

Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2018-06-29T17:28:48Z No. of bitstreams: 1 Dissertac?a?o_Mestrado_Raphaela_ (003).pdf: 1487803 bytes, checksum: 85e14999295df94278920f21e8362c4d (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-09T11:35:44Z (GMT) No. of bitstreams: 1 Dissertac?a?o_Mestrado_Raphaela_ (003).pdf: 1487803 bytes, checksum: 85e14999295df94278920f21e8362c4d (MD5) / Made available in DSpace on 2018-07-09T11:42:43Z (GMT). No. of bitstreams: 1 Dissertac?a?o_Mestrado_Raphaela_ (003).pdf: 1487803 bytes, checksum: 85e14999295df94278920f21e8362c4d (MD5) Previous issue date: 2018-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The increase of environmental pollutants sources directly affects the ecosystem and human health, mainly due to loss of soil and water quality. Among these toxic agents are included endocrine disruptors, which can cause changes in biochemical pathways and physiological changes in organisms. Studies with different forms of bisphenols, compounds present in many products of human consumption and the environment, had already demonstrated extremely adverse effects on behavior and gene expression of targets related to neural and endocrine systems during development. The zebrafish, Danio rerio, is an excellent model organism for studying neurotoxicity, due to its advantages with respect to specific aspects of their development and a low maintenance cost when compared to other vertebrate model organisms. This work proposes the investigation of the effects of bisphenol A (BPA), its chlorinated derivatives and its substitutes (BPS and BPF), toxicological and behavioral parameters combined with characterization of its potential underlying cellular and molecular mechanisms such as cell death and proteins and gene expression in the nervous and endocrine systems. After the embryo and larvae were exposed to different concentrations of BPA and its derivatives, morphological analyzes and embryo survival were carried out, as well as behavioral tests of locomotion and cognitive evaluation of the larvae. In the concentrantion curve of the different bisphenolic compounds, no significant difference was observed in the survival, teratogenesis and hatching of the animals, however, a significant increase was detected in the exploratory parameters of the BPA and BPF groups. When comparing the aversive behavior of the BPA with the DMSO, there was no statistical difference between the groups, whereas in the BPS an improvement in the escape response of the larvae occurred. Additionally, behavioral and locomotor activity analyzes will be performed in adult animals previously treated with the compounds studied during the initial development. In this way, it is expected to contribute to the current knowledge of neurotoxicity mechanisms related to endocrine disruption caused by contaminants of the bisphenol family. / O crescimento das fontes de poluentes ambientais afeta diretamente o ecossistema e a sa?de humana, principalmente devido ? perda da qualidade do solo e da ?gua. Entre estes agentes t?xicos, est?o inclu?dos os disruptores end?crinos, os quais podem acarretar diversas mudan?as em vias bioqu?micas e altera??es fisiol?gicas em organismos. Estudos com diferentes formas de bisfen?is, compostos presentes em diversos produtos de consumo humano e inclusive no ambiente devido ? contamina??o por efluentes industriais, j? apresentaram efeitos extremamente nocivos na regula??o da express?o de genes relacionados ao sistema neural e end?crino durante o desenvolvimento, al?m de altera??es comportamentais severas. O zebrafish, Danio rerio, ? um excelente organismo modelo para estudar neurotoxicidade, uma vez que possui vantagens em rela??o a aspectos espec?ficos do seu desenvolvimento e um custo reduzido de manuten??o quando comparado a outros vertebrados modelos. Este projeto prop?s o estudo dos efeitos do bisfenol A (BPA), seus derivados clorados e substitutivos (BPS e BPF), sobre par?metros de embriotoxicidade e comportamento, buscando tamb?m caracterizar os mecanismos celulares e moleculares dos potenciais efeitos observados avaliando morte celular e n?veis de prote?nas e express?o de genes alvos em embri?es e larvas de zebrafish. Para tanto, ap?s a exposi??o dos embri?es e larvas a diferentes concentra??es de BPA e seus derivados, foram realizadas an?lises morfol?gicas e sobreviv?ncia dos embri?es; ensaios comportamentais de locomo??o e avalia??o cognitiva das larvas. Ao realizar a curva de concentra??o dos diferentes compostos bisfen?licos, n?o foi observada diferen?a significativa na sobreviv?ncia, teratog?nese e eclos?o dos animais, por?m, ao analisar o comportamento explorat?rio dos animais tratados com BPA e BPF foi detectado um aumento significativo nos par?metros explorat?rios das larvas. Ao compararmos o comportamento aversivo do BPA com o controle tratado com o ve?culo DMSO, n?o existiu diferen?a estat?stica entre os grupos, enquanto no BPS ocorreu uma melhora na resposta de escape das larvas. Adicionalmente, ser?o realizadas an?lises comportamentais e de atividade locomotora em animais adultos previamente tratados com os compostos estudados durante o desenvolvimento inicial. Desta forma, espera-se contribuir para o conhecimento atual dos mecanismos de neurotoxicidade relacionados ? disrup??o end?crina causada por contaminantes da fam?lia dos bisfen?is.

In this thesis we investigated the separation of two endocrine disrupting chemicals (EDC), bisphenol-A (BPA) and nonylphenol (NP) from water over the defect free silicalite zeolite. Two force-fields were investigated, the OPLS-AA force-field which is an all-atom one, and the OPLS-UA force-field which is a united atom one. In order to be able to simulate BPA, we simulated and studied the diffusion of different molecules in silicalite. We compared two famous bulk water models, the non-rigid TIP3P modified for CHARMM model and the rigid SPC model, to literature and simulated the diffusion of these water molecules at temperatures from 300K to 600K. We found that these models coupled with our parameters for silicalite compared poorly with literature except for values calculated by Yazaydin et al. The mean-square displacements (MSDs) were more important in the x-direction (sinusoidal channel) than in the expected y-direction (straight channels) for both models resulting in small self-diffusion coefficient values. Results tended to improve as temperature increased. We believe that the high number of hydrogen bonds, implying the presence of clusters of water molecules, is responsible for the poor self-diffusion coefficient. The charges chosen to describe our silicalite zeolite, +2.05, may also be a reason of our small self-diffusion coefficient. We then investigated the self-diffusion of aromatic molecules at 300 and 400K. Benzene, phenol and toluene were studied. We found self-diffusion coefficients for benzene that did not compare well to experiments but that was close to simulation work done by Rungsirisakun et al. Our diffusion coefficients for benzene were several orders of magnitude bigger than the experimental values found in literature for both force-fields. The diffusion patterns for both phenol and toluene did not allow us to calculate self-diffusion coefficients for both investigated force-fields. We believe that the jumps in the MSDs of these molecules are due to the rotation that they undergo in the nanopores. Phenol anchors to the framework by hydrogen-bonds between the hydrogen of its alcohol group and the oxygen of the framework. The diffusion seems to happen when the alcohol group is in a line with one channel. The same diffusion phenomenon was seen for toluene molecule but was related to the methyl group attached to its benzene ring. When this group is in front of a channel, the energetic barrier is reduced and the molecule can diffuse through it. Finally bigger molecules were simulated and studied. Neopentane seemed to have a very low self-diffusion coefficient in silicalite if it could move at all. We report values of self-diffusion of 1.3 10-14 m2.s-1 at both 300K and 400K. This value seems a little high compared to benzene experimental self-diffusion coefficient values that are in the same order of magnitude at both temperatures. The linear nonylphenol molecule that we simulated seemed to diffuse through silicalite with patterns that were close to the one seen for phenol. The hydrogen bonding between its alcohol group and the framework slows down its diffusion in silicalite. With the same reasoning as for phenol we decided not to calculate diffusion coefficient for NP. The last molecule investigated was bisphenol-A (BPA). We found that BPA almost did not diffuse through silicalite. The size of the molecule can explain why it did not diffuse, but we believe that the angle between the two phenol groups should be able to bend enough for it to diffuse, slowly, through silicalite. Our conclusion is that the two phenol groups at both ends of the molecules are the most important factor in its very slow diffusion. Hydrogen bonding is taking place at both ends making it very hard for the molecule to move in the framework. We decided to generate self-diffusion coefficients for this molecule because the diffusion process did not have jumps. We found self-diffusion coefficient that are 3.10-15 m2.s-1 and 15. 10-15 m2.s-1 at 300 and 400K respectively for the OPLS-AA force-field, and 11.6.10-15 m2.s-1 and 6.68.10-15 m2.s-1 at 300 and 400K respectively for the OPLS-UA force-field. The last result was unexpected as we thought that the self-diffusion coefficient was going to increase with temperature. We believe that running much longer simulations for every molecule that we studied should give more reasonable and reliable results as the self-diffusion coefficients values are very small.

Abstract not available

Les substances perturbatrices du système endocrinien sont des substances qui, de par leur capacité à induire des changements hormonaux chez les organismes vivants, génèrent des préoccupations dans le domaine de la qualité des eaux et, par extension, dans le domaine du traitement des effluents aqueux. Particulièrement, ce projet de recherche s’est attardé sur l’élimination des perturbateurs endocriniens phénoliques nonylphénol (NP), bisphénol A (BPA) et triclosan (TCS) en solution aqueuse à l’aide de la laccase (E.C. 1.10.3.2) sécrétée par la souche fongique Coriolopsis polyzona. Cette oxydase est une métalloprotéine pouvant catalyser l’oxydation d’une vaste gamme de substances phénoliques. En premier lieu, l’impact du pH et de la température sur l’élimination de ces composés à l’aide de la laccase libre en utilisant un design factoriel. L’oxydation de ces composés produit des oligomères (dimère à pentamère) via le couplage des radicaux phénoxy produits par l’action de la laccase. Il s’avère que les substances produites suite à l’oxydation du NP et du BPA par la laccase ont perdu leurs similitudes structurales avec l’estrogène. Ainsi, l’élimination de l’activité estrogénique de ces substances est directement liée à la transformation des composés. Finalement, l’utilisation d’ABTS comme médiateur a permis d’augmenter le taux d’oxydation enzymatique de ces composés chimiques. Puis, de façon à augmenter la possibilité d’utilisation de la laccase dans des biotechnologies environnementales, cette enzyme a été immobilisée sur un support siliceux et via la réticulation d’agrégats. L’impact des conditions d’immobilisation sur l’activité enzymatique, la stabilité du catalyseur et les propriété biocatalytiques apparentes a été déterminé pour différentes stratégies d’immobilisation. Globalement, l’immobilisation génère un biocatalyseur stable vis-à-vis les dénaturations chimique, physique et biologique. Particulièrement, l’immobilisation sur un support solide produit un biocatalyseur facile à utiliser ayant une faible activité massique et des propriétés cinétiques moindres que celle de l’enzyme libre. La formation de CLEAs de laccase a permis d’obtenir une activité massique élevée et des propriétés cinétiques supérieures à celle de l’enzyme soluble. Ces biocatalyseurs solides ont étés utilisés pour éliminer en continu le NP, BPA et TCS dans différents types de bioréacteur. Le biocatalyseur sur silice a été utilisé pour éliminer ces substances dans un réacteur garni, tandis que les CLEAs ont été utilisés dans un réacteur à lit fluidisé et un réacteur à perfusion développé au cours de ce projet. Ces différentes configurations de bioréacteur ont permis d’éliminer efficacement ces différents perturbateurs endocriniens. Globalement, les différents résultats obtenus, à l’échelle de laboratoire, au cours de ce projet de recherche démontrent que la laccase et particulièrement les biocatalyseurs formés via les différentes stratégies d’immobilisation testées représentent des approches extrêmement prometteuses pour le développement de biotechnologies environnementales vouées à l’élimination des perturbateurs endocriniens phénoliques.

Evidence from an abundant number of studies suggests that human female reproductive functions have become impaired over the past half century and that there might be a relationship between endocrine disrupting chemicals (EDCs) and reduced fertility. It is, however, not known by what mechanisms EDCs affect different reproductive functions such as endometrial receptivity, embryo implantation and placentation. The endometrium is continuously changing its morphological and functional properties, responding to cyclic changes of oestrogen and progesterone levels during the menstrual cycle. These changes include monthly preparation for embryo implantation through changed endometrial angiogenic activity and consequent changes in endometrial vasculature. Use of primary human endometrial endothelial cells (HEECs) in this work was evaluated as a possible screening tool for effects caused by EDCs on human endometrial vasculature and subsequently on various endometrial functions. In this study HEEC and endometrial stromal cells were isolated. HEECs were grown in monocultures, and together with stromal cells in co-cultures, and exposed to endocrine active substances. These were cadmium, which has oestrogenic properties, tamoxifen, with anti-oestrogenic effects, mifepristone, which is an anti-progestin, and bisphenol A, with oestrogenic properties. The effects were evaluated by using proliferation and viability assays, migration and tube formation assays, quantitative PCR (qPCR), immunohistochemistry and western blot. Cadmium affected the expression of angiogenesis-related genes, and caused different effects in HEECs cultured alone vs. HEECs co-cultured with stromal cells. Tamoxifen altered the expression of angiogenesis-related genes and reduced HEEC migration, thus having an anti-angiogenic effect. Mifepristone caused reduced formation of tubular structures in tube-formation assays involving HEECs co-cultured with stromal cells. Bisphenol A promoted tube formation in co-cultured HEECs which was related to changes in the expression of several angiogenesis-related genes as well as up-regulated expression of VEGF-D protein. In conclusion, we showed that EDCs have the ability to induce changes in endometrial angiogenic activity in vitro and may thus disturb normal endometrial functions related to fertility and pregnancy. HEECs grown in vitro may provide valuable information on the effects of EDCs on human endometrial functions. However, this model is not suitable as a large-scale screening tool.

Environmental chemicals may affect human health by disrupting endocrine function. Many of the endocrine disrupting chemicals (EDCs) are estrogens or estrogen-like molecules that have been classified as environmental estrogens or xenoestrogens (XEs). XEs include endosulfan, chlordance, nonylphenol, bisphenol A, octylphenol, and coumestrol, etc. Although these compounds have wide structural diversity, but all have in common the and/or other hydrophobic components. Many studies have shown that XEs affect cell viability. For instance, Nonylphenol is used in surfactants or plasticizers and bisphenol A (4, 4¡¦-isopropylidene-2-diphenol) is used as protective coatings on food containers and for composites and sealants in dentistry. Most previous studies have focused on the toxicity of XEs on development process and reproductive system, especially in aquatic ecosystems. Thus, the effects of these two environmental chemicals on the toxicological effect are still controversial. The aim of this study is to investigate the molecular mechanisms of nonylphenol and bisphenol A in induction of cell death in human gastric cancer (SCM-1) cells and Madin Darby canine renal tubular (MDCK) cells. First, WST-1 reduction assays and propidium iodide-staining assay were used to determine cell viability and apoptosis in the present of nonylphenol and bisphenol A. Furthermore, we will use immunoblotting to measure the activity of apoptotic markers caspase-3, mitogen-activated protein kinases (MAPKs) to survey how nonylphenol affects apoptotic pathways. Besides, I will explore bisphenol A whether induces cell death and the mechanisms underlying the [Ca2+]i rise in MDCK cells. The results may be helpful for understanding the pharmacological and toxicological effects of these two environmental chemicals in cells from important organs. Results showed that nonylphenol caused apoptosis via the activation of caspase-3 in cultured human gastric cancer (SCM-1) cells. Although nonylphenol could activate the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK), only SB203580 (a p38 MAPK inhibitor) partially prevented cells from apoptosis. Nonylphenol was also found to induce [Ca2+]i increases and pretreatment with BAPTA/AM, a Ca2+ chelator, prevented nonylphenol-induced [Ca2+]i increases, and protect cells from death. These results suggest that nonylphenol induced apoptosis via a Ca2+- and p38 MAPK-dependent pathway. On the other hand, the effect of the environmental contaminant bisphenol A on cytosolic free Ca2+ concentrations ([Ca2+]i) in Madin Darby canine kidney (MDCK) cells is unclear. This study explored whether bisphenol A changed basal [Ca2+]i levels in suspended MDCK cells by using fura-2 as a Ca2+-sensitive fluorescent dye. Bisphenol A at concentrations between 50-300 £gM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced partly by removing extracellular Ca2+. Bisphenol A induced Mn2+ influx, leading to quench of fura-2 fluorescence suggesting Ca2+ influx. This Ca2+ influx was inhibited by phospholiapase A2 inhibitor aristolochic acid, store-operated Ca2+ channel blockers nifedipine and SK&F96365; and protein kinase C inhibitor GF109203X. In Ca2+-free medium, pretreatment with the mitochondrial uncoupler carbonylcyanide m-chlorophenylhydrazone (CCCP) and the endoplasmic reticulum Ca2+ pump inhibitors thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) inhibited bisphenol A-induced Ca2+ release. Conversely, pretreatment with bisphenol A abolished thapsigargin (or BHQ)- and CCCP-induced [Ca2+]i rise. Inhibition of phospholipase C with U73122 abolished bisphenol-induced [Ca2+]i rise. Bisphenol A caused concentration-dependent decrease in cell viability via apoptosis in a Ca2+-independent manner. Collectively, in MDCK cells, bisphenol A induced [Ca2+]i rises by causing phospholipase C-dependent Ca2+ release from the endoplasmic reticulum and mitochondria and Ca2+ influx via phospholipase A2-protein kinase C-sensitive store-operated Ca2+ channels. Key words: calcium, apoptosis, human gastric cancer cells (SCM-1), Madin Darby canine kidney (MDCK), nonylphenol, bisphenol A.