Dans les zones humides, un déclin dramatique des populations d’amphibiens a été observé au niveau mondial depuis les années 80. Malgré de nombreuses études suggérant que les amphibiens sont très sensibles aux pressions anthropiques cumulées, le rôle joué par les perturbateurs endocriniens dans le déclin de leurs populations reste incertain. Parmi les perturbateurs endocriniens contaminants les zones humides, le benzo[a]pyrène (BaP) et le triclosan (TCS) sont couramment retrouvés. Au cours de ce travail, nous avons étudié la réponse physiologique de xénopes (Xenopus tropicalis) exposés à court terme (24 heures) et à long terme (du têtard à l’adulte mature) au BaP et au TCS à des concentrations réalistes d’un point de vue environnemental. En combinant une approche transcriptomique à haut débit et une caractérisation des modifications cellulaires et physiologiques, nous avons mis en évidence que le BaP, le TCS et leur mélange perturbent la physiologie globale du foie. Ce trouble est caractérisé par un phénotype semblable à de l’insulino-résistance et à une stéatopathie non alcoolique (NAFLD) associé à une hépatotoxicité médiée par une altération du métabolisme lipidique. Outre les effets directs sur le métabolisme des individus exposés, il apparaît que les perturbateurs endocriniens étudiés affectent également le succès reproducteur de ces individus et le développement de leur descendance. Prises dans leur ensemble, nos observations apportent ainsi des débuts de réponse quant aux rôles de la contamination chronique des milieux sur le déclin des populations d’amphibiens. / In wetlands, dramatic decline in amphibian populations have been described worldwide since the 80s. Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role played by endocrine disruptors in the decline of amphibian populations remains unclear. Among the endocrine disruptors contaminating wetlands, benzo[a]pyrene (BaP) and triclosan (TCS) are recurrently found. In this work, we studied the physiological response of Xenopus tropicalis exposed to environmentally realistic concentrations of BaP and TCS during a short-term (24 hours) and long-term (from tadpole to mature adult) period. By combining a high throughput transcriptomic approach and a characterization of cellular and physiological modifications, we showed that BaP, TCS and their mixture disrupt overall liver physiology highlighted by insulin resistance-like and non-alcoholic fatty liver disease (NAFLD)-like phenotypes together with hepatotoxicity due to the impairment of lipid metabolism. Additionally to direct metabolic impact observed on exposed individuals, the studied endocrine disruptors affected their fitness and their progeny development. Altogether, our observations bring new insights into the role plays by chronic contamination of wetlands on amphibian population decline.

Made available in DSpace on 2017-07-24T19:38:12Z (GMT). No. of bitstreams: 1 RENATO FONSECA.pdf: 2617015 bytes, checksum: 4bff74d55b32a6bdf1100480e1aa9d39 (MD5) Previous issue date: 2014-03-07 / Emerging micropollutants are characterized as potential risk factors for the environment and for human health. Among these micropollutants is Triclosan (TCS), with antimicrobial action that has been widely used mainly in personal care products which in the environment can affect the biota and produce bacterial resistance. This study aimed to evaluate the presence of TCS in surface waters and effluent from the Sewage Treatment Plant (STP). Surface water samples were collected (10 samples) in the urban area of the city of Ponta Grossa in Arroio Pilão de Pedra (point 1), the Rio Verde upstream (point 2) and downstream (point 3) of the ETE and effluent samples collected within the ETE Rio Verde before (point 4) and after anaerobic treatment (point 5), thus evaluating the effluent itself and the presence of TCS. Physical and chemical evaluations were also conducted on points 1, 2 and 3 in order to verify the quality of the aquatic environment. The techniques used for the physical-chemical evaluations were based on Molecular Spectroscopy UV absorption, which are all carried out in triplicate. As for the determination of TCS, a high performance chromatography liquid was employed (HPLC) preceded by pre-concentration in the solid state with the technique being implemented after validation. The chromatographic analyzes were performed employing a chromatograph Allcrom YL9100 with C-18 (250 mm x 4.6 mm x 5 m), mobile phase acetonitrilal / water (65:35) with isocratic elution and UV-Vis detector. The solvents used are all HPLC grade and ultrapure Milli-Q water . The chromatographic analyzes were performed under a flow (output) of 1mL/min, injection volume 400 μL, average pressure of 2360 psi and a temperature of 30 º C. The pre-concentration of the samples was performed using the technique of solid phase extraction (SPE) using cartridges C18/18 Applied Separations. The physical-chemical evaluation of the samples collected in the Green River showed a decline in the quality of the water after disposal of treated effluent. High biochemical oxygen demand (BOD) and high chemical oxygen demand (COD), high concentrations of total organic carbon (TOC), surfactants (SFT) and total phosphorus (TPHO), as well as reduced levels of dissolved oxygen (DO) were observed in the Rio Verde downstream of ETE. The Arroio Pilão de Pedra showed similar characteristics to the Rio Verde after disposal of treated effluent. TCS was detected in two of the selected points for the chromatographic analysis (points 3 and 4) at concentrations averaging 33, 23ug L-1 points. The results demonstrate a relationship between waters impacted by raw sewage or the effluent of ETE inflow, and the presence of TCS. / Os micropoluentes emergentes são caracterizados como potenciais fatores de riscos ambientais e de problemas para a saúde humana. Dentre estes micropoluentes, está o Triclosan (TCS), que com ação antimicrobiana vem sendo amplamente utilizado principalmente em produtos de higiene pessoal, mas que no ambiente pode afetar a biota e produzir resistência bacteriana. O presente trabalho teve como objetivo avaliar a presença de TCS em águas superficias e efluente de Estação de Tratamento de Esgoto (ETE). Amostras de águas superficiais foram coletadas (10 coletas) na área urbana da cidade de Ponta Grossa no Arroio Pilão de Pedra (ponto 1), no Rio Verde a montante (ponto 2) e a jusante (ponto 3) da ETE, e amostras de efluente coletadas no interior da ETE Rio Verde antes (ponto 4) e após tratamento anaeróbio (ponto 5), avaliando assim o próprio efluente quanto a presença de TCS. Avaliações físico-químicas também foram realizadas nos pontos 1, 2 e 3 com a finalidade de verificar a qualidade do ambiente aquático. As técnicas utilizadas para as avaliações físico-químicas estiveram baseadas na Espectroscopia de Absorção Molecular no Ultravioleta (UV), sendo todas estas realizadas em triplicata. Já para a determinação do TCS empregou-se cromatografia líquida de alta eficiência (CLAE) precedida de pré-concentração em fase sólida, sendo a técnica implantada após validação. As análises cromatográficas foram realizadas empregando-se um cromatógrafo Allcrom YL9100 com coluna C-18 (250 mm x 4,6 mm x 5 m), fase móvel acetonitrilal/água (65:35), com eluição isocrática e detector UV-Vis. Os solventes utilizados são todos grau HPLC e a água ultra-pura Milli-Q. As análises cromatográficas foram realizadas sob um fluxo (vazão) de 1mL/min, volume de injeção de 400 μL, pressão média de 2360 psi e temperatura de 30ºC. A pré-concentração das amostras foi realizada através da técnica de extração em fase sólida (EFS) empregando cartuchos C18/18 Applied Separations. A avaliação físico-química das amostras coletadas no Rio Verde mostrou declínio da qualidade da água após descarte de efluente tratado. Alta demanda bioquímica de oxigênio (DBO) e alta demanda química de oxigênio (DQO), concentrações elevadas de carbono orgânico total (COT), surfactantes (SFT) e fósforo total (FOST), assim como níveis reduzidos de oxigênio dissolvido (OD) foram verificados no Rio Verde a jusante da ETE. O Arroio Pilão de Pedra apresentou características semelhantes ao Rio Verde após descarte do efluente tratado. O TCS foi detectado em dois dos pontos selecionados para análise cromatográfica (pontos 3 e 4) em concentrações médias de 33, 23ug L-1. Os resultados demonstram uma relação entre águas impactadas por esgoto bruto ou pelo aporte de efluente da ETE, e a presença de TCS.

Introdução: Os efeitos antimicrobianos de óleos essenciais têm sido relatados na literatura científica, sobretudo referentes ao óleo essencial de Melaleuca alternifolia, também denominado óleo essencial de Tea Tree (OTT). Tal óleo essencial apresenta propriedades antissépticas e pode representar uma alternativa de um produto natural para higienização das mãos (HM) nos estabelecimentos de assistência à saúde que atualmente utilizam predominantemente produtos à base de triclosan e clorexidina. Objetivo: Avaliar a eficácia antimicrobiana na higiene das mãos realizada com três diferentes formulações de sabonetes líquidos distintos, contendo: óleo essencial de Melaleuca alternifolia a 2,0%; sabonete com triclosan a 0,5%; sabonete com clorexidina a 2,0%, bem como compreender de que forma o uso de um sabonete com óleo essencial na higienização das mãos na prática assistencial é percebido por profissionais de saúde. Métodos: Para o experimento (etapa quantitativa) foram utilizadas as diretrizes da metodologia do Comitê Europeu de Padronização, EN1499 versão abril 2013 (phase2/step2), indicada para avaliar a eficácia de antissépticos para higienização das mãos. Foram contaminadas artificialmente as mãos de 15 voluntários sadios com Escherichia coli K12, seguida pela lavagem das mãos utilizando-se cada um dos produtos em avaliação ou um sabão de referência (soft soap). Realizou-se a contagem do número de microrganismos antes (pré-valores) e após (pós-valores) cada procedimento e foi estabelecida a redução logarítmica microbiana para cada um dos participantes em cada procedimento. Os dados foram analisados aplicando-se dois testes não paramétricos. Para a obtenção dos dados qualiquantitativos realizaram-se entrevistas cujos discursos foram analisados conforme metodologia proposta pelo discurso do sujeito coletivo (DSC). Resultados: ao ser aplicado o Teste de Wilcoxon, os três sabonetes testados obtiveram resultados superiores ao do sabão de referência (soft soap) e foram considerados antimicrobianos; constatou-se ainda a superioridade do sabonete contendo OTT e contendo triclosan em relação ao sabonete com clorexidina. Quando aplicado o Teste de Friedman, os sabonetes contendo triclosan e OTT, que apresentaram eficácias equivalentes, podem ser considerados antimicrobianos. A maior parte dos profissionais tinha algum conhecimento sobre Aromaterapia (65,21%), mas menos da metade conhecia as aplicações do OTT (43,47%). Profissionais mais jovens e menos experientes acharam o aroma do OTT agradável ou forte, mas não desagradável. Profissionais mais experientes e com mais idade o associaram ao aroma de pinho e levantaram a questão de o aroma ser incômodo para alérgicos. As principais diferenças observadas entre o sabonete com OTT e os demais sabonetes da prática assistencial foram em relação a aspectos físicos, como textura mais agradável, ao aroma e ao fato de ser menos agressivo à pele. A não agressão à pele foi considerada pelos participantes como o grande diferencial do sabonete contendo OTT, sobrepondo-se, inclusive, ao fator aroma, e que poderia contribuir para aumentar a adesão à HM. Conclusão: os sabonetes contendo OTT 2,0% e contendo triclosan 0,5% demonstraram desempenho superior em relação à clorexidina 2,0%. O não ressecamento da pele por produtos de HM é fundamental para aumentar a adesão dos profissionais de saúde. Além disso, a presença do aroma no sabonete pode ou não ser um fator de estímulo. / Introduction: The antimicrobial effects of essential oils have been reported in the scientific literature, especially regarding the essential oil of Melaleuca alternifolia, also known as tea tree essential oil (TTO). This essential oil has antiseptic properties and can represent a natural-product alternative for hand hygiene (HH) in health-care settings, which currently use mainly products based on triclosan and chlorhexidine. Objective: To evaluate the antimicrobial efficacy in HH performed using three distinct liquid soap formulations containing 2.0% Melaleuca alternifolia essential oil; 0.5% triclosan; 2.0% chlorhexidine and assess how using a soap with essential oil for HH in healthcare practice is perceived by health professionals. Methods: For the experiment (quantitative phase) we used the methodology guidelines of the European Committee for Standardization, EN1499 version April 2013 (phase2/step2), indicated to evaluate the efficacy of antiseptics for HH. The hands of 15 healthy volunteers were artificially contaminated with Escherichia coli K12 and then the hands were washed with each of the products being assessed or the reference soap (soft soap). The number of microorganisms was counted before (pre-values) and after (post-values) each procedure and microbial logarithmic reduction was performed for each of the participants in each procedure. Data were analyzed using two non-parametric tests. To obtain the qualiquantitative data, interviews were carried out, of which contents were analyzed according to the methodology proposed by the Collective Subject Discourse (CSD). Results: When the Wilcoxon test was applied, the three assessed soaps showed better results than the reference soap (soft soap) and were considered as exhibiting antimicrobial action; the soaps containing TTO and triclosan showed to be superior to the one containing chlorhexidine. When Friedmans test was applied, the soaps containing triclosan and TTO, which showed similar efficacy, were considered antimicrobials. Most of the professionals had some knowledge of aromatherapy (65.21%), but less than half knew about TTO uses (43.47%). Younger and less experienced professionals found the smell of TTO pleasant or strong, but not unpleasant. Older and more experienced professionals associated it to the smell of pine and raised the question of the smell being displeasing for allergic individuals. The main differences between the TTO soap and the other soaps used in health care practice were related to the physical aspects, such as a more pleasant texture, smell and the fact of its being less aggressive to the skin. The fact that it was less aggressive to the skin was perceived by participants as the great differential of the soap containing TTO, overriding even the scent factor, which could help to increase adherence to HH. Conclusion: The soaps containing 2.0% TTO and 0.5% triclosan showed superior performance when compared to the one with 2.0% chlorhexidine. The fact that a soap used in HH does not dry the skin is considered a critical point for adherence by health care professionals. Additionally, the soap smell may or may not be a stimulating factor for HH.

Introdução: Os efeitos antimicrobianos de óleos essenciais têm sido relatados na literatura científica, sobretudo referentes ao óleo essencial de Melaleuca alternifolia, também denominado óleo essencial de Tea Tree (OTT). Tal óleo essencial apresenta propriedades antissépticas e pode representar uma alternativa de um produto natural para higienização das mãos (HM) nos estabelecimentos de assistência à saúde que atualmente utilizam predominantemente produtos à base de triclosan e clorexidina. Objetivo: Avaliar a eficácia antimicrobiana na higiene das mãos realizada com três diferentes formulações de sabonetes líquidos distintos, contendo: óleo essencial de Melaleuca alternifolia a 2,0%; sabonete com triclosan a 0,5%; sabonete com clorexidina a 2,0%, bem como compreender de que forma o uso de um sabonete com óleo essencial na higienização das mãos na prática assistencial é percebido por profissionais de saúde. Métodos: Para o experimento (etapa quantitativa) foram utilizadas as diretrizes da metodologia do Comitê Europeu de Padronização, EN1499 versão abril 2013 (phase2/step2), indicada para avaliar a eficácia de antissépticos para higienização das mãos. Foram contaminadas artificialmente as mãos de 15 voluntários sadios com Escherichia coli K12, seguida pela lavagem das mãos utilizando-se cada um dos produtos em avaliação ou um sabão de referência (soft soap). Realizou-se a contagem do número de microrganismos antes (pré-valores) e após (pós-valores) cada procedimento e foi estabelecida a redução logarítmica microbiana para cada um dos participantes em cada procedimento. Os dados foram analisados aplicando-se dois testes não paramétricos. Para a obtenção dos dados qualiquantitativos realizaram-se entrevistas cujos discursos foram analisados conforme metodologia proposta pelo discurso do sujeito coletivo (DSC). Resultados: ao ser aplicado o Teste de Wilcoxon, os três sabonetes testados obtiveram resultados superiores ao do sabão de referência (soft soap) e foram considerados antimicrobianos; constatou-se ainda a superioridade do sabonete contendo OTT e contendo triclosan em relação ao sabonete com clorexidina. Quando aplicado o Teste de Friedman, os sabonetes contendo triclosan e OTT, que apresentaram eficácias equivalentes, podem ser considerados antimicrobianos. A maior parte dos profissionais tinha algum conhecimento sobre Aromaterapia (65,21%), mas menos da metade conhecia as aplicações do OTT (43,47%). Profissionais mais jovens e menos experientes acharam o aroma do OTT agradável ou forte, mas não desagradável. Profissionais mais experientes e com mais idade o associaram ao aroma de pinho e levantaram a questão de o aroma ser incômodo para alérgicos. As principais diferenças observadas entre o sabonete com OTT e os demais sabonetes da prática assistencial foram em relação a aspectos físicos, como textura mais agradável, ao aroma e ao fato de ser menos agressivo à pele. A não agressão à pele foi considerada pelos participantes como o grande diferencial do sabonete contendo OTT, sobrepondo-se, inclusive, ao fator aroma, e que poderia contribuir para aumentar a adesão à HM. Conclusão: os sabonetes contendo OTT 2,0% e contendo triclosan 0,5% demonstraram desempenho superior em relação à clorexidina 2,0%. O não ressecamento da pele por produtos de HM é fundamental para aumentar a adesão dos profissionais de saúde. Além disso, a presença do aroma no sabonete pode ou não ser um fator de estímulo. / Introduction: The antimicrobial effects of essential oils have been reported in the scientific literature, especially regarding the essential oil of Melaleuca alternifolia, also known as tea tree essential oil (TTO). This essential oil has antiseptic properties and can represent a natural-product alternative for hand hygiene (HH) in health-care settings, which currently use mainly products based on triclosan and chlorhexidine. Objective: To evaluate the antimicrobial efficacy in HH performed using three distinct liquid soap formulations containing 2.0% Melaleuca alternifolia essential oil; 0.5% triclosan; 2.0% chlorhexidine and assess how using a soap with essential oil for HH in healthcare practice is perceived by health professionals. Methods: For the experiment (quantitative phase) we used the methodology guidelines of the European Committee for Standardization, EN1499 version April 2013 (phase2/step2), indicated to evaluate the efficacy of antiseptics for HH. The hands of 15 healthy volunteers were artificially contaminated with Escherichia coli K12 and then the hands were washed with each of the products being assessed or the reference soap (soft soap). The number of microorganisms was counted before (pre-values) and after (post-values) each procedure and microbial logarithmic reduction was performed for each of the participants in each procedure. Data were analyzed using two non-parametric tests. To obtain the qualiquantitative data, interviews were carried out, of which contents were analyzed according to the methodology proposed by the Collective Subject Discourse (CSD). Results: When the Wilcoxon test was applied, the three assessed soaps showed better results than the reference soap (soft soap) and were considered as exhibiting antimicrobial action; the soaps containing TTO and triclosan showed to be superior to the one containing chlorhexidine. When Friedmans test was applied, the soaps containing triclosan and TTO, which showed similar efficacy, were considered antimicrobials. Most of the professionals had some knowledge of aromatherapy (65.21%), but less than half knew about TTO uses (43.47%). Younger and less experienced professionals found the smell of TTO pleasant or strong, but not unpleasant. Older and more experienced professionals associated it to the smell of pine and raised the question of the smell being displeasing for allergic individuals. The main differences between the TTO soap and the other soaps used in health care practice were related to the physical aspects, such as a more pleasant texture, smell and the fact of its being less aggressive to the skin. The fact that it was less aggressive to the skin was perceived by participants as the great differential of the soap containing TTO, overriding even the scent factor, which could help to increase adherence to HH. Conclusion: The soaps containing 2.0% TTO and 0.5% triclosan showed superior performance when compared to the one with 2.0% chlorhexidine. The fact that a soap used in HH does not dry the skin is considered a critical point for adherence by health care professionals. Additionally, the soap smell may or may not be a stimulating factor for HH.

Cette étude a eu pour objectif de contribuer à une meilleure compréhension du comportement photochimique de certains micropolluants de type antibiotiques vétérinaires (sulfaquinoxaline, pyriméthamine) ou antibactérien (triclosan) en solution aqueuse et à la surface de la kaolinite, utilisée comme un modèle de sol.L’étude du comportement photochimique de la sulfaquinoxaline a été réalisée sous excitation à 254 nm et 365 nm. Dans tous les cas, une dégradation efficace est observée avec un rendement quantique qui dépend de la longueur d’onde d’excitation, du pH et la concentration d’oxygène dissous. De plus, la présence de l’oxygène moléculaire dans le milieu conduit à une inhibition partielle la photodégradation mettant en évidence l’implication partielle de l’état excité triplet. Ce dernier a pu être mis en évidence par photolyse laser nanoseconde à travers un transfert Triplet-Triplet (T-T) en employant le β-carotène comme accepteur. Sur le plan analytique, la phototransformation de la sulfaquinoxaline conduit à la formation d’un grand nombre de produits qui ont été identifiés par HPLC/ESI/MS/MS en identifiant les processus de fragmentation intervenant pour chaque molécule étudiée. L’étude a permis de montrer que les états excités singulet et triplet sont tout les deux impliqués dans la photodegradation et que les processus principaux intervenant sont la photohydrolyse, la désulfonation avec un réarrangement intramoléculaire, l'hydroxylation des motifs aromatiques et l'isomérisation selon un processus de type photo Fries.L’étude de la photoréactivité de la pyriméthamine a montré que la dégradation est plus efficace avec la forme neutre. Le rendement quantique a été évalué à environ 4,0x10-2 en milieu aéré et sous excitation à 254 nm. L’étude par photolyse laser a montré la formation intermédiaire de l’état excité triplet mais également de l’électron solvaté (absorption à 700 nm). Les processus de formation des photoproduits primaires sont la substitution de l’atome de chlore par un groupement hydroxyle ou par un atome d’hydrogène et l’hydroxylation du noyau aromatique.La dégradation des micropolluants à la surface du sol a pu être abordée en utilisant l’argile kaolinite comme support modèle. Ce système simplifié nous a permis d’étudier la photodégradation sous excitation en Suntest sur le plan cinétique et analytique. L’étude cinétique a été entreprise en fonction de différents paramètres tels que l’épaisseur de la kaolinite et la concentration initiale du substrat. Le premier effet nous a permis de montrer que pour des épaisseurs inférieures à 70 µm, la vitesse de diffusion du composé des zones sombres vers les zones irradiées est très rapide devant la photolyse et de ce fait, elle peut être négligée. Cet aspect a conduit à la détermination du rendement quantique de disparition à la surface de la kaolinite. Sur le plan analytique, les réactions observées sur l’argile sont différentes de celles observées en solution aqueuse. En effet, dans le cas de la sulfaquinoxaline, seul le produit de désulfonation est observé. Au contraire de la sulfaquinoxaline, l’étude complète de la molécule de triclosan a montré la formation de plusieurs produits et notamment des dimères ou des oligomères ce qui suggère la présence du substrat sous forme d’agrégats à la surface de l’argile. Afin de confirmer cette observation expérimentale, nous avons abordé une étude de modélisation par dynamique moléculaire. Celle-ci a donnée des informations très importantes sur l’organisation des molécules à la surface de la kaolinite. Ainsi, l’adsorption du triclosan fait intervenir d'importantes liaisons hydrogène avec la surface de la kaolinite. En présence de plusieurs molécules, la formation d’agrégats est gouvernée par une importante interaction entre les noyaux aromatiques de type π-stacking. / The study undertaken within this thesis concerns the photochemical behavior of the veterinary antibiotics sulfaquinoxaline and pyrimethamine, as well as the antimicrobial triclosan in aqueous solutions and at the surface of kaolin, used as a soil model.The photochemical study on sulfaquinoxaline was performed at 254 and 365 nm. In all cases, an efficient degradation was observed with a quantum yield that depends on the excitation wavelength, pH and the dissolved molecular oxygen concentration. Molecular oxygen acts as an inhibitor which reflects the involvement of the triplet excited state. Sulfaquinoxaline was clearly shown to be a photosensitizer of β-carotene via a triplet-triplet transfer process. From the analytical point of view, several photoproducts were generated and identified by using HPLC/ESI/MS/MS technique through a close analysis of the fragmentation processes. The byproducts that were formed via the singlet as well as the triplet excited states were mainly generated by photohydrolysis, desulfonation, hydroxylation and isomerisation reactions.The photochemical study of pyrimethamine indicates an efficient photoreactivity with the molecular form. The laser flash photolysis study reveals the implication of singlet and triplet excited states. The byproducts were mainly formed through the substitution of the chlorine atom by an hydroxyl group and the hydroxylation of the aromatic moiety.The photochemical study at the surface of soil was undertaken by using kaolin as a model support. Such simple system appears to be a guideline for precise kinetic and analytical studies. The former was performed as a function of several important parameters such as the layer thickness and the initial concentration of the substrate. The first parameter clearly indicates that for a thickness lower than 70 µm, the rate of diffusion is so fast that this process can be neglected when compared to the photochemical process. Thus, the first rate constant at the surface of kaolin was determined. Only the product of desulfonation was observed with sulfaquinoxaline while with triclosan, several byproducts were obtained such as dimers and oligomers suggesting the formation of aggregates at the surface of the solid support. In order to confirm this aspect, molecular dynamics studies were undertaken and indicate that the adsorption of triclosan mainly occurs at the surface of kaolin via hydrogen molecular bonds. The arrangement of the molecules in a cluster is governed by π-stacking type interactions between the aromatic moieties.

This Thesis deals with the construction of an electrochemical cell with two types of integrated composite electrodes based on carbon films. Using these electrodes, the voltammetric behavior of environmental pollutant triclosan (5-chlor-2-(2,4- dichlorophenoxy)phenol) was studied. For the construction of composite electrodes, graphite and glassy carbon were used as conductive microparticles. Several types of polymers served as the nonconductive binder. For the measurements, combinations of graphite with polystyrene and graphite with polycarbonate were selected as optimum materials. From the dependence of peak heights on solution composition, a mixture of a buffer of pH 7 and methanol (1:9, V/V) was selected as the optimum medium. In this medium, concentration dependences were measured; calculated triclosan detection limit were 0,49 µmol dm-3 for carbon polystyrene composite electrode and 0,25 µmol dm-3 for carbon polycarbonate composite electrode, respectively. The possibility of further increasing the sensitivity of the determination by the accumulation step was studied. Accumulation of triclosan on carbon polystyrene composite electrode was observed, but the increase in response was connected with the loss of repeatability. Accumulation of triclosan on carbon polycarbonate composite electrode was...

Bakgrund: Postoperativa sårinfektioner drabbar ca 2,3 % av de patienter som genomgått ett kirurgiskt ingrepp i svensk hälso- och sjukvård. Dessa infektioner kan ge upphov till förlängd vårdtid, ytterligare kirurgiska ingrepp och ökad mortalitet. Postoperativa sårinfektioner innebär ett lidande för patienten samtidigt som det är kostsamt för sjukvården. Inom sjukvården används utarbetade arbetssätt för att minska riskerna för att patienten ska drabbas. Samtidigt utvecklas och studeras nya metoder i det preventiva arbetet mot postoperativa sårinfektioner, exempelvis suturer belagda med antibakteriella substanser. En av dessa är triklosanbelagda suturer. Dock råder viss oenighet om dess preventiva effekter och roll i det förebyggande arbetet mot postoperativa sårinfektioner. Syfte: Studiens syfte var att undersöka om suturer med beläggning av triklosan har en förebyggande effekt mot postoperativa sårinfektioner. Metod: Studien utformades som en systematisk litteraturstudie med metaanalys av 7 randomiserade kontrollerade studier. Dessa studier hade en uppföljningstid om 30 dagar samt använt bedömningskriterier för förekomst av postoperativa sårinfektioner enligt CDC, Centers for Disease Control and Prevention. Resultat: Inget statistiskt signifikant resultat kunde erhållas gällande triklosanbelagda suturers preventiva effekt mot postoperativa sårinfektioner. (RR=0,8, 95 % CI=0,63-1,02, p=0.07). Slutsats: Studien indikerar att triklosanbelagda suturer inte rutinmässigt bör användas i preventivt syfte mot postoperativa sårinfektioner. Ytterligare forskning behövs på området. / Background: Approximately 2,3 % of the patients undergoing surgery in Swedish healthcare develop surgical site infections. These infections are often associated with prolonged hospital stay, additional surgical procedures and increased mortality. Surgical site infections cause patient suffering and increase healthcare costs. In healthcare, standard guidelines and work methods are used to prevent patients from developing surgical site infections. New methods to reduce the risk of surgical site infections are being developed and studied, such as sutures with antibacterial coating. One of these is Triclosan-coated sutures. However, there is some disagreement on its preventive effects and role in reducing surgical site infections. Aim: The aim of this study was to investigate if Triclosan-coated sutures have a preventive effect against surgical site infections. Method: This study was conducted as a systematic literature review with meta-analysis of 7 RCT. These studies all had a follow up time of 30 days and used the criteria of CDC, Centers for Disease Control and Prevention, to identify surgical site infections. Result: This study showed no statistically significant results of Triclosan-coated sutures preventive effect against surgical site infections. (RR=0,8, 95 % CI=0,63-1,02, p=0.07). Conclusion: This study indicates that Triclosan-coated sutures should not be used routinely to prevent surgical site infections. More studies are needed.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-09-19T17:06:54Z No. of bitstreams: 1 JosimarAraujo.pdf: 950712 bytes, checksum: 6ec752a1c9c3751ffeba0d040eb09762 (MD5) / Made available in DSpace on 2017-09-19T17:06:54Z (GMT). No. of bitstreams: 1 JosimarAraujo.pdf: 950712 bytes, checksum: 6ec752a1c9c3751ffeba0d040eb09762 (MD5) Previous issue date: 2017-09-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present work describes a study of the construction of an electrochemical sensor involving sol-gel process and molecular imprinting for detection of triclosan. The sol-gel process is a process in which a network is formed from a solution, by progressively changing a liquid precursor, from a sol to a gel and, in most cases, finally to a dry network. In turn, molecular imprinting is a method of induced formation of some predetermined selectivity recognition element for some template molecule. Thus, for the determination of the template molecule triclosan, 5-chloro-2-(2,4-dichlorophenoxy)-phenol, the following steps were performed: 1) verification of a glassy carbon electrode modified with chitosan and multi-walled carbon nanotubes, and molecularly imprinted siloxanes, would be suitable for the voltammetric detection of triclosan; 2) to observe if a network would be formed with the sol-gel process and to evaluate the mechanical stability of the electrochemical sensor constructed; 3) to evaluate the modified electrode as an electrochemical sensor with selectivity, specificity and detection limit for the determination of triclosan in aqueous solutions; 4) to verify the applicability of the proposed sensor by detecting of triclosan oxidation in real samples. The results showed that glassy carbon electrode modified with chitosan, multi-walled carbon nanotubes and molecularly imprinted siloxanes, constructed by sol-gel and molecular imprinting processes, presented mechanical stability, sensitivity, selectivity, specificity and applicability as an electrochemical sensor for the detection of triclosan in commercial samples of physical moisturizer and of toothpaste. / O presente trabalho descreve um estudo da construção de um sensor eletroquímico envolvendo processo sol-gel e impressão molecular para detecção de triclosan. O processo sol-gel é um procedimento no qual uma rede é formada a partir de uma solução. Esta formação é por meio de uma mudança progressiva deste líquido inicial, de um sol para um gel e, na maioria dos casos, finalmente para uma rede seca. Por sua vez, a impressão molecular é um método de formação induzida de elementos de reconhecimento com seletividade predeterminada para alguma molécula molde. Assim, para a determinação da molécula molde triclosan, 5-cloro-2- (2,4-diclorofenoxi)-fenol, as seguintes etapas foram executadas: 1) verificar se um eletrodo de carbono vítreo modificado com quitosana, nanotubos de carbono de paredes múltiplas e siloxanos molecularmente impressos seria adequado para a detecção voltamétrica do triclosan; 2) averiguar a formação de uma rede com o processo sol-gel e avaliar a estabilidade mecânica do sensor eletroquímico construído; 3) avaliar a sensibilidade do eletrodo modificado como um sensor eletroquímico com seletividade, especificidade e limite de detecção para a determinação de triclosan em soluções aquosas; e 4) comprovar a aplicabilidade do sensor proposto mediante a detecção de sinal de oxidação de triclosan em amostras reais. Os resultados mostraram que eletrodos de carbono vítreo modificados com quitosana, nanotubos de carbono de paredes múltiplas e siloxanos molecularmente impressos, construídos por processo sol-gel e impressão molecular, apresentaram estabilidade mecânica, sensibilidade, seletividade, especificidade e aplicabilidade como um sensor eletroquímico para a detecção de triclosan em amostras comerciais de hidratante corporal e de creme dental.

Adult Oral Health Programme: The Effect of Periodontal Treatment and the Use of a Triclosan Containing Toothpaste on Glycaemic Control in Diabetics Abstract Aim: The aim of the research study is to establish an adult oral health programme for diabetics in Majuro, Republic of the Marshall Islands in order to determine the impact of non-surgical periodontal treatment followed by the use of a triclosan containing dentifrice on the maintenance of periodontal health and glycaemic control in type 2 diabetic patients. Hypothesis: Non-surgical periodontal treatment results in improved periodontal health and better glycaemic control in diabetics and use of a triclosan containing toothpaste is effective in maintaining this improvement in diabetics. Methods: An adult oral health programme was created, within which was conducted a two-group randomised clinical trial to address the hypothesis that non-surgical periodontal treatment results in improved periodontal health and better glycaemic control in type 2 diabetics and that the use of a triclosan containing toothpaste is effective in maintaining this improvement in diabetics. In this double blind controlled trial, sixty adult patients (aged 35 to 65 years) with type 2 diabetes mellitus having a minimum of 16 teeth received non-surgical periodontal treatment. Half of the patients were randomly assigned to use a triclosan containing toothpaste, Colgate Total, and the other group a non-triclosan toothpaste, Colgate Fluoriguard. The study evaluated the improvement in periodontal health by recording Probing Pocket Depth (PPD) on 6 sites of each tooth, and the number of sites bleeding on probing (BOP) at baseline, and at 6 months and 12 months after treatment. The second part of the study evaluated the impact of improvement of periodontal health on glycaemic control in type 2 diabetics by measuring HbA1c and RBS, and also assessing the levels of C-Peptides and CRP at baseline, and at 6 months and 12 months after treatment. The study also evaluated the effectiveness of a triclosan containing toothpaste in maintaining the improvement in periodontal health after non-surgical periodontal treatment. Results: The results showed that it was feasible to establish an oral health programme for the diabetics and could improve their periodontal health, and that toothpaste containing triclosan is effective in maintaining the improved periodontal heath in type 2 diabetics. Mean PPD dropped from 2.35mm to 1.95mm in the triclosan group and from 2.49mm to 2.24 mm in the non-triclosan group and the mean number of BOP sites dropped from 4.9 to 2.8 in the triclosan group and from 4.7 to 3.2 in the fluoriguard at 12 month visits. However, the results did not show improvement of HbA1c nor RBS levels in either group. C-Peptide levels increased and C-Reactive Protein levels decreased in both groups, however, not to significant levels at 12 month visits. Conclusion: The results of this research study lead to the conclusion that treating periodontal infection has effect of periodontal health of type 2 diabetic patients and following-up with simple personal oral hygiene of regular tooth-brushing helps maintain their periodontal health. This programme also proved that this type of oral health programme is feasible and valuable for diabetics in isolated places like the Marshall Islands, where infrastructure, personnel and resources are limited to treat microvascular and macrovascular complications of diabetes. As for the effectiveness of treating periodontal infections on glycaemic control of diabetics, this study failed to support the hypothesis that non-surgical treatment plus triclosan containing toothpaste would lead to better glycaemic management through improved periodontal health.

<p>This work explores the usefulness of fish bile analysis in combination with biomarkers for identifying and evaluating new environmental contaminants in the aquatic environment. It illustrates how bile analysis can be used together with biomarkers to assess the causes of estrogenic effects, to identify chemicals in the aquatic environment that are taken up by fish, and to monitor environmental exposure.</p><p>In a first application, fish exposed to sewage treatment plant effluent were studied. Elevated levels of vitellogenin in the exposed fish demonstrated that estrogenic effects occurred. Several estrogen disrupting substances were identified in the fish bile, and analysis of water samples confirmed that these substances were present in the effluent. The synthetic estrogen 17a-ethinylestradiol, which is known to be present in sewage treatment plant effluent, was shown for the first time to be taken up by fish. Considering the reported potencies of the detected substances, it was concluded that 17a-ethinylestradiol was the major contributor to the estrogenic effects.</p><p>Chemical analysis of bile was used to identify rubber additives that were released from tires immersed in water. The bile of rainbow trout held in the water contained high levels of metabolites of PAHs and aromatic nitrogen compounds. Several biomarkers were also measured in the exposed fish, and EROD induction and oxidative stress were observed. Based on the bile analysis observations together with knowledge of toxicological mechanisms, it was postulated that the EROD induction was due to the PAHs, while aromatic nitrogen compounds caused the oxidative stress.</p><p>Resin acids in fish bile proved to be a good indicator of exposure in a chronic long-term study of rainbow trout exposed to effluent from a total chlorine free (TCF) pulp mill. Elevated levels of GST (gluthatione-S-transferase) and GR (gluthatione reductase) activity, and the presence of DNA adducts after a two month recovery period, indicated that compounds in the pulp mill effluents have persistent effects. In addition to characterising the exposure of the fish to the effluent, the analysis of the resin acids in the bile provided evidence of accidents in the pulp mill that the existing process monitoring system had not detected.</p><p>Resin acids in bile were also found to be a valuable indicator of exposure to pulp mill effluents for eelpout living in the Baltic Sea. A correlation between resin acid levels in bile and skewed sex ratios provided an important link in the chain of evidence that substances in the pulp mill effluents cause male bias of the eelpout embryos.</p><p>A particularly good example of the potential of bile analysis was the identification of a previously unknown environmental contaminant. A large peak was observed in the bile extracts of fish that had been exposed to sewage treatment plant effluent. This peak was identified as triclosan, which demonstrated its presence in sewage treatment plant effluent. Other work went on to show that it is a common contaminant of the aquatic environment. The ability of fish to concentrate contaminant metabolites in bile to levels very much higher than in the environment, and the comparatively low levels of analytic interferences, make bile a particularly attractive matrix to search for new, unknown organic pollutants</p>