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Síntese e caracterização de metaloporfirinas imobilizadas em SBA-15 como catalisadores biomiméticos na oxidação de hidrocarbonetos / \"Synthesis and Characterization of Metalloporphyrins immobilized in SBA-15 as Catalysts at Biomimetic Oxidation of Hydrocarbons\"Zanatta, Lucas Dimarô 07 March 2014 (has links)
As metaloporfirinas (MeP) cloreto de 5,10,15,20-tetra(pentafluorofenill)porfirina de manganês (III) e ferro (III) (MnIIIP e FeIIIP) foram imobilizadas em matriz de sílica híbrida mesoporosa do tipo SBA-15. Os grupos silanóis da SBA-15 foram modificados com (3-aminopropil)trietoxissilano (APTES) e (3-aminopropil)dietoximetilsilano (APDES), que após a imobilização das metaloporfirinas geraram os catalisadores FeP-APSBA, FeP-APMSBA, MnP-APSBA e MnP-APMSBA. Um terceiro tipo de material foi preparado a partir da ligação de grupos trimetilsilil (TMS) nos catalisadores FeP-APSBA e MnP-APSBA, gerando outros dois catalisadores que foram denominados FeP-APSBA-TMS e MnP-APSBA-TMS. Os materiais foram caracterizados por FTIR, RD UV-Vis, TG/TGA MEV, MET e isotermas de adsorção e dessorção de N2 (BET/BJH). Para analisar a natureza da interação solvente-superfície nos materiais, foram determinadas medidas goniométricas de energia livre de superfície. Os catalisadores foram estudados na oxidação dos substratos (Z)-ciclo-octeno e ciclo-hexano, utilizando iodosilbenzeno (PhIO) como espécie doadora de oxigênio a fim de avalia-los como biomiméticos do citocromo P450. Os parâmetros estruturais foram comparados aos resultados catalíticos frente à formação da gaiola de solvente e das espécies intermediárias de alta valência, FeIV(O)P+. e MnV(O)P e estudar como esses fatores afetam o rendimento e a seletividade das reações catalisadas. As MeP-SBAs apresentaram uma faixa de rendimento de 88 a 47 % para epoxidação de (Z)-ciclo-octeno. Já na oxidação de ciclo-hexano houve formação de 2 a 8 % de ciclo-hexanol e 2 % de ciclo-hexanona. Observou-se maior seletividade para o álcool com as FeP-SBAs. / Manganese (III) and iron (III) 5,10,15,20- tetra(pentafluorophenyl) porphyrin (MnIIIP and FeIIIP ) chloride were immobilized in mesoporous silica hybrid matrix SBA-15. Silanol groups were modified with (3-aminopropyl)triethoxysilane (APTES) and (3-aminopropyl)diethoxymethylsilane (APDES), generating catalysts called FeP-APSBA, FeP-APMSBA, MnP-APSBA and MnP-APMSBA. A third type of material was prepared from the binding trimethylsilyl groups (TMS) in FeP-APSBA and MnP- APSBA catalysts generating the other two catalysts named FeP-APSBA-TMS and MnP-APSBA-TMS. The materials were characterized by FTIR , DR UV-Vis , TG/TGA SEM , TEM and adsorption and desorption isotherms of N2 (BET/BJH) and to analyze the materials solvent - surface interaction nature the were determined goniometric measurements of surface free energy. Catalysts were evaluated for (Z)- cyclooctene and cyclohexane oxidation mediated by iodosylbenzene (PhIO) as the oxygen donor species to evaluate their catalytic activity as cytochrome P450 biomimetics. Structural parameters were compared to catalytic results related to cage solvent formation and the intermediate species high valence FeIV(O)P+. and MnV(O) P and how these factors affect the yield and selectivity of catalysts. MeP-SBA\'s reactions showed a range of 88-47 % for epoxidation (Z)-cyclooctene and cyclohexane oxidation yielding 2 to 8 % of cyclohexanol and 2 % of cyclohexanone. In the latter case was observed a higher selectivity for alcohol with FeP-SBA\'s.
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Pharmacokinetic drug-drug interactions in the management of malaria, HIV and tuberculosisElsherbiny, Doaa January 2008 (has links)
<p> Malaria, Human Immunodeficiency Virus (HIV) and tuberculosis (TB) are global health problems having their worst situation in sub-Saharan Africa. Consequently, concomitant use of antimalarial, antiretroviral and antitubercular drugs may be needed, resulting in a potential risk of drug-drug interactions.</p><p>Cytochrome P-450 (CYP) enzyme induction/inhibition may lead to drug-drug interactions and can be detected by probe drugs. An analytical method was developed for the quantitation of mephenytoin, CYP2B6 and CYP2C19 probe, and its metabolites. </p><p>Induction/inhibition of principal CYP enzymes by the antimalarials; artemisinin, dihydroartemisinin, arteether, artemether and artesunate, was evaluated using the 4-hour plasma concentration ratios of probe drugs and their metabolites along with modelling the population pharmacokinetics of S-mephenytoin and its metabolites. The extent of change in enzymatic activities was different among the antimalarials, with artemisinin having strongest capacity for induction and inhibition, consequently, the strongest potential risk for drug-drug interactions. </p><p>Drug-drug interactions between the antitubercular rifampicin and the antiretrovirals nevirapine and lopinavir were assessed, in TB/HIV patients, by developing population pharmacokinetic models. Rifampicin increased nevirapine oral clearance. Simulations suggested that increasing the nevirapine dose to 300 mg twice daily when co-administered with rifampicin, would result in nevirapine concentrations above subtherapeutic levels, with minimum exposure above the recommended maximum concentration. Lopinavir is co-formulated with ritonavir in the ratio of 4:1. In children, increasing ritonavir dose four times did not completely compensate the enhancement of lopinavir oral clearance caused by rifampicin. However, the predicted lopinavir trough concentration was above the recommended minimum therapeutic concentration.</p><p>The work presented in this thesis followed an investigation line though not done for a particular drug. First the CYP enzymes involved in the interaction are identified. Afterwards, the expected drug-drug interaction is investigated where the potentially interacting drugs are concomitantly administered and an adjustment in the dose regimen is proposed that is subsequently evaluated.</p>
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Pharmacokinetic drug-drug interactions in the management of malaria, HIV and tuberculosisElsherbiny, Doaa January 2008 (has links)
Malaria, Human Immunodeficiency Virus (HIV) and tuberculosis (TB) are global health problems having their worst situation in sub-Saharan Africa. Consequently, concomitant use of antimalarial, antiretroviral and antitubercular drugs may be needed, resulting in a potential risk of drug-drug interactions. Cytochrome P-450 (CYP) enzyme induction/inhibition may lead to drug-drug interactions and can be detected by probe drugs. An analytical method was developed for the quantitation of mephenytoin, CYP2B6 and CYP2C19 probe, and its metabolites. Induction/inhibition of principal CYP enzymes by the antimalarials; artemisinin, dihydroartemisinin, arteether, artemether and artesunate, was evaluated using the 4-hour plasma concentration ratios of probe drugs and their metabolites along with modelling the population pharmacokinetics of S-mephenytoin and its metabolites. The extent of change in enzymatic activities was different among the antimalarials, with artemisinin having strongest capacity for induction and inhibition, consequently, the strongest potential risk for drug-drug interactions. Drug-drug interactions between the antitubercular rifampicin and the antiretrovirals nevirapine and lopinavir were assessed, in TB/HIV patients, by developing population pharmacokinetic models. Rifampicin increased nevirapine oral clearance. Simulations suggested that increasing the nevirapine dose to 300 mg twice daily when co-administered with rifampicin, would result in nevirapine concentrations above subtherapeutic levels, with minimum exposure above the recommended maximum concentration. Lopinavir is co-formulated with ritonavir in the ratio of 4:1. In children, increasing ritonavir dose four times did not completely compensate the enhancement of lopinavir oral clearance caused by rifampicin. However, the predicted lopinavir trough concentration was above the recommended minimum therapeutic concentration. The work presented in this thesis followed an investigation line though not done for a particular drug. First the CYP enzymes involved in the interaction are identified. Afterwards, the expected drug-drug interaction is investigated where the potentially interacting drugs are concomitantly administered and an adjustment in the dose regimen is proposed that is subsequently evaluated.
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Daf-9, a cytochrome P450 regulating C. elegans larval development and adult longevity /Jia, Kailiang, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 134-144). Also available on the Internet.
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Daf-9, a cytochrome P450 regulating C. elegans larval development and adult longevityJia, Kailiang, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 134-144). Also available on the Internet.
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Drug-related problems with special emphasis on drug-drug interactionsMannheimer, Buster, January 2009 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 4 uppsatser.
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Molecular basis for the anti-inflammatory properties of chlomethiazole /Simi, Anastasia, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
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On the role of cytochrome P450 3A4 in the metabolism of cholesterol and bile acids /Bodin, Karl, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.
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Mechanisms of activation of the aryl hydrocarbon receptor by novel inducers of the CYP1A1 gene /Backlund, Maria, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
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Novel extrahepatic P450 enzymes with emphasis on the tumor specific CYP2W1 /Karlgren, Maria, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.
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