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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Estudo comparativo de efetividade da terapia cognitivo-comportamental em grupo e dos inibidores seletivos de recaptação da serotonina em pacientes com transtorno obsessivo-compulsivo: um ensaio clínico pragmático / Comparative effectiveness study of group cognitive-behavioral therapy and of selective serotonin reuptake inhibitors in patients with obsessive-compulsive disorder: a pragmatical clinical trial

Cristina Belotto da Silva 04 March 2009 (has links)
Introdução: A Terapia Cognitivo-Comportamental (TCC) e os inibidores seletivos de recaptação de serotonina (ISRS) são considerados os tratamentos de primeira linha para o Transtorno Obsessivo-Compulsivo (TOC) nos ensaios clínicos randomizados (ECR). No entanto, a maior parte destes estudos exclui grande parte dos pacientes (em torno de 50%) por apresentarem comorbidades psiquiátricas. Ensaios clínicos pragmáticos e de efetividade, que costumam simular ambientes clínicos naturalísticos ao estudar amostras que representam melhor a população real comparando tratamentos ativos, são de grande importância para as decisões tomadas por um sistema de saúde e poucos têm sido feitos para avaliar a efetividade dos tratamentos para o TOC. O objetivo do presente estudo foi comparar os tratamentos de primeira linha para o TOC em uma amostra mais próxima da população que procura atendimento e avaliar características clínicas associadas às respostas aos tratamentos. Metodologia: Pacientes de 18 a 65 anos de idade, com escore de linha de base da YBOCS de pelo menos 16 para obsessões e compulsões, ou pelo menos 10 apenas para obsessões ou compulsões e com possíveis comorbidades psiquiátricas adicionais foram alocados seqüencialmente para tratamento de TCC em grupo (TCCG; n = 70) ou para tratamento medicamentoso (ISRS; n = 88). A TCCG consistiu em doze sessões semanais de duas horas cada com grupos de 6 a 8 pacientes, baseadas em um manual validado (Cordioli, 2002). O medicamento utilizado foi a fluoxetina com dosagem máxima de 80mg/dia. Foram analisadas respostas aos tratamentos como variáveis contínua (redução percentual na YBOCS) e categórica (redução de pelo menos 35% na YBOCS e ICG 1 muito melhor ou 2 melhor. Resultados: Os escores da YBOCS reduziram 23,13% no grupo tratado com TCCG e 21,54% no grupo tratado com ISRS, sem diferença estatística entre os grupos de tratamento (p = 0,875). Foi encontrada em 33,3% dos pacientes de TCCG e 27,7% dos pacientes de ISRS a redução de pelo menos 35% no escore da YBOCS e resposta à ICG 1 ou 2 (p = 0,463). O número médio de comorbidades psiquiátricas por paciente foi 2,7; e 81,4% da amostra apresentou pelo menos uma comorbidade. A redução na YBOCS foi significativamente menor entre os pacientes com uma ou mais comorbidade psiquiátrica (21,15% e 18,73%, respectivamente) do que entre os pacientes com TOC puro (34,62%) (p = 0,034). Sexo masculino, apresentar um escore inicial mais alto na Beck-A, ter abandonado o tratamento e apresentar comorbidade com Transtorno Depressivo Maior ou Distimia foram associados com taxas mais baixas de resposta ao tratamento, independente do tratamento recebido. Os resultados sugeriram que em uma população mais heterogênea os tratamentos de primeira linha para o TOC são menos efetivos. É necessário o desenvolvimento de intervenções que sejam efetivas para uma população da prática clínica / Introduction: Cognitive-Behavioral Therapy (CBT) and selective serotonin reuptake inhibitors (SSRI) are considered the first line treatments for Obsessive-Compulsive Disorder (OCD) in randomized controlled trials (RCT). However, most of these trials exclude a great amount of patients (around 50%) for presenting psychiatric comorbidities. Pragmatical and effectiveness clinical trials simulate natural clinical environments and compare active treatments in samples that represent the real population. These trials are of great importance for decision makers of the health public system, and only a few trials have investigated the effectiveness of treatments to OCD. The aim of this study was to compare the first line OCD treatments in a sample closer to the OCD real population, and to evaluate clinical characteristics associated to responses to treatments. Methodoly: Patients (1865 years; baseline Yale-Brown Obsessive-Compulsive Scale (YBOCS) scores 16; potentially presenting additional psychiatric comorbidities) were sequentially allocated for treatment with group CBT (GCBT; n=70) or pharmacological treatment (SSRI; n=88). GCBT consisted in twelve two hours weekly sessions with groups of 6 to 8 patients, based in a validated manual (Cordioli, 2002). Medication utilized in SSRI group was fluoxetine, 80mg/day. Response to treatment was analyzed as continuous variable (percent reduction on YBOCS) and as categorical variable (reduction of at least 35% on YBOCS and CGI 1 much better or 2 better. Results: Mean Y-BOCS scores fell by 23.13% in the GCBT and 21.54% in the SSRI group. Symptom reduction did not differ between groups (p = 0.875). A reduction of at least 35% in baseline Y-BOCS score and a CGI rating of 1 (much better) or 2 (better) was achieved by 33.3% of patients in the GCBT and 27.7% in the SSRI group (p=0.463). Patients presented 2.7 mean number of psychiatric comorbidity, and 81.4% showed at least one additional disorder. The YBOCS reduction was significantly lower in patients with one or more psychiatric comorbidities (21.15%, and 18.73%, respectively) than those with pure OCD (34.62%) (p = 0.034). Low responses to treatments were found to be associated to: being male, presenting a high initial Beck-A score, comorbid major depression, dysthymia and abandoning treatment, independently of the treatment received. The development of effective interventions to a real population is necessary
122

Influência da inibição da glicoproteína-P pela fluoxetina na disposição cinética dos enantiômeros da fexofenadina em parturientes e suas relações com a transferência placentaria / Effect of P-gp inhibition by fluoxetine on the kinetic disposition and of fexofenadine enantiomers in parturients and their relationships with transplacental transfer

Leonardo Santos Ribeiro Pinto 05 August 2015 (has links)
Interações medicamentosas envolvendo a glicoproteína-P (P-gp) intestinal e placentária são determinantes na disposição cinética e transferência placentária de medicamentos durante a gestação. A fexofenadina, fármaco anti-histamínico, está disponível na clínica como racemato com indicação de uso durante a gravidez para o tratamento da rinite alérgica sazonal e urticária crônica. Considerando a fexofenadina como um substrato da P-gp e a fluoxetina, fármaco antidepressivo indicado durante a gravidez, um inibidor da P-gp, o presente estudo investiga a influência da fluoxetina na disposição cinética enantiosseletiva da fexofenadina em parturientes e suas relações com a transferência placentária in vivo e ex vivo. No estudo in vivo foram investigadas 16 parturientes, sendo 8 incluídas no grupo Controle e 8 incluídas no grupo Interação. Todas as parturientes investigadas receberam dose única oral de 60mg de fexofenadina racêmica, enquanto as parturientes do grupo Interação receberam também dose única oral de 40mg de fluoxetina racêmica 3 h antes da administração da fexofenadina. As amostras seriadas de sangue e urina foram colhidas até 48 h após a administração da fexofenadina. Na resolução do parto (2-3 h após a administração da fexofenadina) foram coletadas simultaneamente amostras de sangue materno, venoso e arterial do cordão umbilical e do espaço interviloso placentário. No modelo ex vivo, a farmacocinética transplacentária dos enantiômeros da fexofenadina foi avaliada em 4 lóbulos de placenta humana. Os enantiômeros da fexofenadina foram determinados nas amostras de plasma, urina e solução de perfusão placentária por LC-MS/MS acoplado a coluna de fase estacionária quiral Chirobiotic® V. A análise farmacocinética foi realizada empregando o programa WinNonlin e os testes estatísticos foram realizados com o auxílio do programa R. A disposição cinética da fexofenadina é enantiosseletiva no plasma materno com maiores valores de AUC0-? (423,20 vs 267,67 ng×h/mL) e menores valores de volume de distribuição aparente (621,37 vs 889,83 L), clearance total aparente (66,20 vs 105,05 L/h) e clearance renal aparente (5,25 vs 8,78 L/h) para o distômero (R)-(+)-fexofenadina. A transferência placentária da fexofenadina é limitada com razões de concentrações plasmáticas veia umbilical/veia materna de aproximadamente 0,16 para ambos os enantiômeros. As razões enantioméricas R-(+)/S-(-) de aproximadamente 1,7 nos compartimentos materno e fetal sugerem que a P-gp placentária não discrimina entre os enantiômeros da fexofenadina. A administração de dose única oral de 40 mg de fluoxetina racêmica 3 h antes da administração da fexofenadina aumentou os valores de AUC0-? (376,09 vs 267,67 ng×h/mL) e reduziu os valores de clearance total aparente (74,37 vs 105,05 L/h) e clearance renal aparente (3,50 vs 8,78 L/h) somente para o eutômero (S)-(-)-fexofenadina, inferindo inibição enantiosseletiva da P-gp intestinal. A administração de dose única oral de 40 mg de fluoxetina racêmica 3 h antes da administração da fexofenadina [concentrações plasmáticas materna no momento da extração fetal de 11, 9, 7 e 3 ng/mL, respectivamente para os enantiômeros (S)-(+)-fluoxetina, (R)-(-)-fluoxetina, (S)-(+)-norfluoxetina e (R)-(-)-norfluoxetina] não altera as razões de concentrações plasmáticas veia umbilical/veia materna e as razões enantioméricas R-(+)/S-(-) nos compartimentos materno e fetal. No modelo ex vivo, a transferência placentária da fexofenadina é lenta e limitada com razões de concentrações reservatório ii fetal/reservatório materno de aproximadamente 0,18 para ambos os enantiômeros. As razões enantioméricas R-(+)/S-(-) de aproximadamente 1,0 nos compartimentos materno e fetal confirmam que a P-gp placentária não discrimina entre os enantiômeros da fexofenadina. As concentrações clinicamente relevantes de 50 ng de cada enantiômero da fluoxetina/mL não alteram as razões de concentrações reservatório fetal/reservatório materno, a velocidade de transferência placentária e as razões enantioméricas R-(+)/S-(-) nos compartimentos materno e fetal. As razões de concentrações dos enantiômeros da fexofenadina reservatório fetal/reservatório materno obtidas no modelo ex vivo são similares às razões obtidas no estudo clínico de concentrações plasmáticas veia umbilical/veia materna, inferindo a validade do modelo ex vivo de predição da transferência placentária in vivo dos enantiômeros da fexofenadina. Concluindo, os estudos in vivo e ex vivo permitem inferir que a fluoxetina inibe de maneira enantiosseletiva a P-gp intestinal e não inibe a P-gp placentária em concentrações clinicamente relevantes / Drug-drug interaction on the intestinal and placental P-glycoprotein (P-gp) plays an important role in the kinetics disposition and placental transfer of drugs during pregnancy. Fexofenadine is an antihistamine drug for seasonal allergic rhinitis and chronic urticaria treatment during pregnancy and it is available as a racemic mixture. Taken together fexofenadine as a P-gp substrate and fluoxetine, antidepressant drug used in pregnancy, as a P-gp inhibitor, this study asses the effect of fluoxetine on the enantioselective kinetic disposition of fexofenadine in pregnant women at term and their relationships with in vivo and ex vivo transplacental transfer. The in vivo study investigated 16 parturients, 8 included in Control group and 8 included in Interaction group. All of parturients received 60 mg of racemic fexofenadine in a single oral dose, while Interaction group subjects were also given 40 mg of racemic fluoxetine in a single oral dose 3 h before fexofenadine administration. Serial blood and urine samples were collected for 48 h after fexofenadine administration. Maternal blood, venous and arterial umbilical cord blood, as well as placental intervillous space blood samples were simultaneously collected at delivery (2-3 h after fexofenadine administration). The transplacental pharmacokinetics of fexofenadine enantiomers was assayed in 4 placental lobule using ex vivo placental perfusion model. Fexofenadine enantiomers were determined in plasma, urine and placental perfusate samples by LC-MS/MS equipped with the chiral column Chirobiotic® V. Pharmacokinetic parameters were determined using WinNonlin and statistical analyses were performed using R statistical software. Fexofenadine kinetics disposition is enantioselective in maternal plasma with higher AUC0-? values (423.20 vs. 267.67 ng×h/mL) and lower apparent volume of distribution values (621.37 vs. 889.83 L), apparent total clearance (66.20 vs. 105.05 L/h) and apparent renal clearance (5.25 vs. 8.78 L/h) for (R)-(+)-fexofenadine distomer. Fexofenadine placental transfer is limited, with umbilical vein/maternal vein plasma concentration ratios of approximately 0.16 for both enantiomers. R-(+)/S-(-) enantiomeric ratios of approximately 1.7 in both maternal and fetal compartments indicate that placental P-gp might not have ability of fexofenadine\'s chiral discrimination. Single oral dose administration of 40 mg of racemic fluoxetine 3 h before fexofenadine administration increased AUC0-? values (376.09 vs. 267.67 ng×h/mL) and lowered both apparent total clearance values (74.37 vs. 105.05 L/h) and apparent renal clearance (3.50 vs. 8.78 L/h) only for (S)-(-)-fexofenadine eutomer, inferring intestinal P-gp enantioselective inhibition. Single oral dose administration of 40 mg of racemic fluoxetine 3 h before fexofenadine administration [maternal plasma concentrations at delivery of 11, 9, 7 and 3 ng/mL for (S)-(+)-fluoxetine, (R)-(-)-fluoxetine, (S)-(+)-norfluoxetine and (R)-(-)-norfluoxetine enantiomers, respectively] does not change either umbilical vein/maternal vein plasma concentration ratios or R-(+)/S-(-) enantiomeric ratios in maternal and fetal compartments. In the ex vivo model, placental transfer of fexofenadine is slow and limited, presenting fetal/maternal reservoirs concentration ratios of approximately 0.18 for both enantiomers. R-(+)/S-(-) enantiomeric ratios of approximately 1.0 on maternal and fetal compartments confirm placental P-gp does not have ability of fexofenadine\'s chiral discrimination. Clinically relevant concentrations of 50 ng of each fluoxetine enantiomer/mL neither alter fetal/maternal reservoirs concentration ratios, placental transfer rate nor R-(+)/S-(-) enantiomeric ratios in maternal and fetal iv compartments. Fetal/maternal reservoirs concentration ratios of fexofenadine enantiomers obtained in the ex vivo model are similar to those obtained in the clinical study of umbilical vein/maternal vein plasma concentrations, implying the validity of ex vivo model to predict placental transfer of fexofenadine enantiomers in vivo. In conclusion, both in vivo and ex vivo studies allow us to infer that fluoxetine enantioselectively inhibits intestinal P-gp and yet does not inhibit placental P-gp at clinically relevant concentrations.
123

Análise estereosseletiva de fármacos com aplicação em estudos de biotransformação empregando fungos / Stereoselective analysis of drugs with application in biotransformation studies employing fungi

Keyller Bastos Borges 27 July 2010 (has links)
Este trabalho teve por finalidade o desenvolvimento e validação de métodos para análise estereosseletiva de alguns fármacos e metabólitos, bem como a aplicação desses métodos na avaliação do potencial de fungos, principalmente endofíticos, em processos de biotransformação. Os seguintes fármacos foram selecionados para esse estudo: fluoxetina, propranolol, omeprazol, oxibutinina e ibuprofeno. Para determinação simultânea dos enantiômeros da fluoxetina (FLX) e norfluoxetina (NFLX) em meios de cultura de fungos endofíticos, empregou-se a cromatografia líquida de alta eficiência com detecção por absorção no ultravioleta, em um sistema com duas colunas em série, sendo uma de fase reversa (C18) e outra com fase estacionária quiral (Chirobiotic® V). A fase móvel foi composta por etanol: tampão acetato de amônio 15 mmol L-1, pH 5,90: acetonitrila (77,5: 17,5: 5, v/v/v) e a detecção foi realizada em 227 nm. A extração líquido-líquido foi empregada na preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 12,5 a 3750 ng mL-1 (r 0,996) para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 10%. Nas condições empregadas, os cinco fungos endofíticos estudados não foram capazes de promover a biotransformação da FLX (reação de demetilação). A eletroforese capilar foi empregada para análise enantiosseletiva do propranolol (PROP) e 4-hidroxipropranolol (4-OHPROP). A melhor condição de resolução dos enantiômeros foi encontrada com a aplicação de um planejamento experimental de Box-Behnken: solução de eletrólitos composta por tampão trietilamina / ácido fosfórico (TEA/H3PO4), 25 mmol L-1, pH 9,00, carboximetil--ciclodextrina 4% (m/v) como seletor quiral e análise realizada na voltagem de 17 kV. O método de extração líquido-líquido também foi empregado para preparação das amostras. As curvas analíticas foram lineares no intervalo de concentração de 0,25 a 10,0 g mL-1 para 4-OHPROP e de 0,10 a 10,0 g mL-1 para PROP, apresentando coeficientes de correlação (r) 0,995 para todos os enantiômeros analisados. Os coeficientes de variação e erros relativos obtidos nos estudos de precisão e exatidão foram inferiores a 15%. Os cinco fungos endofíticos em estudo se mostraram eficientes na biotransformação estereosseletiva do PROP, com maior formação do metabólito (-)-(S)-4-OHPROP. O fungo Glomerella cingulata (VA1), em especial, apresentou uma concentração de 1,745 g mL-1 do enantiômero (-)-(S)-4-OHPROP depois de 72 horas de incubação, ao passo que a formação do enantiômero (+)-(R)-4-OHPROP não foi observada. A utilização deste fungo em escalas ampliadas pode ser uma fonte promissora de obtenção do metabólito 4-OHPROP na forma enantiomericamente pura. A determinação simultânea de omeprazol (OMZ), 5-hidroxiomeprazol (5-HOMZ) e omeprazol sulfona (OMZ SUL) em meio de cultura Czapek Dox modificado ii tamponado foi realizada empregando um método rápido de análise por cromatografia líquida de ultra eficiência com detector por arranjo de diodos (UPLC / DAD), usando coluna monolítica de fase reversa e eluição por gradiente. OMZ, 5-HOMZ e OMZ SUL foram extraídos das amostras utilizando uma mistura de acetato de etila: t-butil metil éter (9: 1, v/v). A separação foi obtida empregando uma coluna RP 18 Chromolith Fast Gradient endcapped e fase móvel constituída por 0,15% (v/v) de ácido trifluoroacético (TFA) em água (solvente A) e 0,15% (v/v) de TFA em acetonitrila (solvente B). Os tempos de retenção foram de 0,70 min para 5-HOMZ, 0,74 min para OMZ, 0,77 min para OMZ SUL e 0,91 min para o padrão interno (bupropiona, BUP). O método foi linear no intervalo de 0,2 a 10,0 g mL-1 (r 0,995) para todos os analitos. O processo de biotransformação foi realizado durante apenas 24 horas de incubação, por causa de problemas de estabilidade do OMZ. Por esse mesmo motivo, a biotransformação estereosseletiva não foi avaliada. Apenas três fungos apresentaram formação do metabólito 5-HOMZ, e dentre estes, apenas o fungo Botritis cinerea (BC) produziu esse metabólito em concentração superior ao limite de quantificação do método. A formação do metabólito OMZ SUL foi observada para todos os fungos, exceto para Glomerella cingulata (VA1) e Guignardia mangiferae (VA15). Esses fungos podem ser úteis para a obtenção dos metabólitos do OMZ, mas estudos detalhados do comportamento do fármaco nas condições de cultivo são necessários, uma vez que este substrato pode sofrer degradação em meio ácido e na presença de luz. A análise simultânea dos enantiômeros da oxibutinina (OXY) e da N-desetiloxibutinina (DEOB) em meio de cultura Czapek foi obtida empregando a cromatografia líquida de alta eficiência com detector UV (HPLC/UV). Os analitos foram separados usando coluna quiral Chiralpak AD e fase móvel constituída por hexano: isopropanol: etanol: dietilamina (94: 4: 2: 0,05, v/v/v/v) e detectados em 210 nm. Um estudo piloto de biotransformação empregando os mesmos fungos e as condições de biotransformação utilizadas para os demais fármacos mostrou que não houve a formação do metabólito de interesse. Além disso, não houve uma diminuição significativa da concentração de OXY durante o período de incubação, o que poderia ser um indicativo da formação de outros metabólitos não monitorados nas condições de análise. Como a reação de desetilação da OXY para formar a DEOB não foi observada nos experimentos, não foi necessário realizar a validação do método analítico. A separação simultânea do ibuprofeno (IBP), dos enantiômeros do 2-hidroxi-ibuprofeno (2-OH-IBP) e dos estereoisômeros do carboxi-ibuprofeno (COOH-IBP) foi realizada empregando-se uma coluna Chiralpak AS-H e fase móvel constituída por hexano: isopropanol: TFA (95: 5: 0,1, v/v/v). O solvente extrator usado na extração líquido-líquido foi uma mistura de hexano: acetato de etila (1: 1, v/v). A detecção foi feita por espectrometria de massas (MS/MS), com a fonte de ionização por eletronebulização operada no modo positivo (ESI+). O método foi linear nos intervalos de 0,1 a 20,0 g mL-1 para IBP, de 0,05 a 7,5 g mL-1 para o cada enantiômero do 2-OH-IBP e de 0,025 a 5,0 g mL-1 para cada estereoisômero do COOH-IBP. Os demais parâmetros de validação obtidos para o método apresentaram-se dentro dos limites recomendados pela literatura. Os sete fungos endofíticos estudados se mostraram eficientes na biotransformação do IBP em seu principal metabólito 2-OH-IBP, mas apenas os fungos Nigrospora sphaerica (SS67) e Chaetomium globosum (VR10) iii biotransformaram o IBP de forma enantiosseletiva mais acentuada, observando-se maior formação do metabólito ativo (+)-(S)-2-OH-IBP. A não estereosseletividade observada para os demais fungos pode ser indício de uma possível conversão quiral do fármaco, similar a que ocorre em humanos. A formação dos estereoisômeros do COOH-IBP não foi observada, provavelmente, porque sua rota de formação envolve uma seqüência de reações. Os resultados apresentados nesse trabalho mostram que fungos, particularmente os endofíticos, podem ser uma fonte promissora para obtenção de metabólitos de fármacos, inclusive de forma enantiomericamente pura. / This work aimed the development and validation of suitable methods for the stereoselective analysis of some drugs and metabolites, as well as, the application of these methods to assess the potential of fungi, mainly the endophytic ones, in biotransformation processes. The following drugs were selected for this study: fluoxetine, propranolol, omeprazole, oxybutynin and ibuprofen. The simultaneous determination of fluoxetine (FLX) and norfluoxetine (NFLX) enantiomers in culture media of endophytic fungi was carried out by high-performance liquid chromatography with UV-detection, in a system of two columns coupled in series, in which one of them was a reversed phase (C18) column and the another one was a chiral stationary phase column (Chirobiotic ® V). The mobile phase consisted of ethanol: ammonium acetate buffer, 15 mol L-1, pH 5.90: acetonitrile (77.5: 17.5: 5, v/v/v) and the detection was performed at 227 nm. Liquid-liquid extraction was employed for sample preparation. The analytical curves were linear over the concentration range of 12.5 to 3750 ng mL-1 (r 0.996) for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of method precision and accuracy were lower than 10%. In the studied conditions, the five endophytic fungi used were not able to perform the biotransformation of FLX (demethylation reaction). Capillary electrophoresis was employed for the enantioselective analysis of propranolol (PROP) and 4-hydroxypropranolol (4-OHPROP). The best condition for enantiomer resolution was obtained by applying an experimental design of Box-Behnken: electrolyte solution composed of triethylamine / phosphoric acid (TEA/H3PO4) buffer, 25 mmol L-1, pH 9.00, with 4% (w/v) carboxymethyl--cyclodextrin as the chiral selector and analysis performed at 17 kV. Liquid-liquid extraction was also used for sample preparation. The analytical curves were linear over the concentration range of 0.25 to 10.0 g mL-1 for 4-OHPROP and 0.10 to 10.0 g mL-1 for PROP, presenting correlation coefficients (r) 0.995 for all enantiomers evaluated. The coefficients of variation and relative errors obtained in the evaluation of precision and accuracy were lower than 15%. All the five endophytic fungi (Phomopsis sp. (TD2), Glomerella cingulata (VA1), Penicillium crustosum (VR4), Chaetomium globosum (VR10) and Aspergillus fumigatus (VR12)) showed effectiveness in the stereoselective biotransformation of PROP, with higher formation of (-)-(S)-4-OH-PROP. The fungus Glomerella cingulata (VA1), in particular, showed a concentration of 1.745 g mL-1 for the enantiomer (-)-(S)-4-OHPROP after 72 hours of incubation, whereas there was no formation of the enantiomer (+)-(R)-4-OHPROP. Therefore, the use of this fungus in large scale may be a promising source to obtain 4-OHPROP in the enantiomerically pure form. A fast analytical method based on ultra-performance liquid chromatography / diode array detector (UPLC/DAD) using a monolithic reversed phase column and gradient elution was developed for the simultaneous determination of omeprazole (OMZ), 5-hydroxyomeprazole (5-HOMZ) and omeprazole sulfone (OMZ SUL) in modified and buffered Czapek-Dox culture medium. OMZ, 5-HOMZ and OMZ SUL were extracted using a mixture of ethyl acetate: methyl t-butyl ether (9: 1, v/v). The separation was achieved using a Chromolith Fast Gradient RP 18 endcapped column with the mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B). Retention times were 0.70 min for 5-HOMZ, 0.74 min for OMZ, 0.77 min for OMZ SUL and 0.91 min for internal standard (bupropion, BUP). The method was linear over the concentration range of 0.2 to 10.0 g mL-1 (r 0.995) for all analytes. The biotransformation process was carried out only within 24 hours of incubation, due to OMZ instability. For the same reason, the stereoselectivity in this process was not evaluated. The formation of the metabolite 5-HOMZ was observed only for three fungi, and among them, only the fungus Botrytis cinerea (BC) produced this metabolite in concentrations higher than the limit of quantification. The formation of OMZ SUL was observed for all fungi, except for Guignardia mangiferae (VA1) and Glomerella cingulata (VA15). The fungi evaluated in this study can be useful to obtain the metabolites of OMZ, but detailed study of the drug stability in culture conditions is required, since this substrate can undergo degradation in acidic conditions and in the presence of light. The simultaneous analysis of oxybutinin (OXY) and N-desethyloxybutinin (DEOB) enantiomers in Czapek culture medium was carried out by liquid chromatography with UV detection (HPLC/UV). The analytes were separated using a Chiralpak AD column employing as mobile phase hexane: isopropanol: ethanol: diethylamine (94: 4: 2: 0.05, v/v/v/v) and detection at 210 nm. A pilot study of biotransformation using the same fungi and conditions employed for the biotransformation of the other drugs showed that the metabolite of interest was not formed. Moreover, the decrease in the concentration of OXY, which could be indicative of the formation of other metabolites not monitored under the conditions of analysis, was not observed. Since the reaction of OXY desethylation to form DEOB was not observed in the experiments, the validation of the analytical method was not required. The method for the simultaneous analysis of ibuprofen (IBP), 2-hydroxyibuprofen (2-OH-IBP) enantiomers and carboxyibuprofen (IBP-COOH) stereoisomers was developed using a Chiralpak AS-H column and a mobile phase consisting of hexane: isopropanol: TFA (95: 5: 0.1, v/v/v). A mixture of hexane: ethyl acetate (1: 1, v/v) was used as solvent extractor for sample preparation. The detection was performed by tanden mass spectrometry (MS/MS) with the electrospray interface operated in the positive mode (ESI+). The method was linear over the concentration range of 0.1 to 20.0 g mL-1 for IBP, 0.05 to 7.5 g mL-1 for each 2-OH-IBP enantiomer and 0.025 to 5.0 g mL-1 for each COOH-IBP stereoisomer. The other validation parameters studied were within the limits established in the literature. The seven studied endophytic fungi showed to be efficient in the biotransformation of IBP to its main metabolite 2-OH-IBP, however, only the fungi Nigrospora sphaerica (SS67) and Chaetomium globosum (VR10) biotransformed IBP enantioselectively, with greater formation of the active metabolite (+)-(S)-2-OH-IBP. The lack of stereoselectivity observed for the other fungi could be caused by a possible chiral inversion process occurring for IBP, in a similar way that happens in humans. The formation of COOH-IBP stereoisomers was not observed probably because the route of formation of this metabolite requires a sequence of reactions. The results presented here show that fungi, particularly the endophytic ones, may be a promising source to obtain the metabolites of drugs, including in their enantiomerically pure form.
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Efeito da fluoxetina na reabsorção de água pelo rim / Fluoxetine effect on kidney water absorption

Zenaide Providello Moysés 09 April 2007 (has links)
A patogenia da hiponatremia decorrente do uso da Fluoxetina em pacientes idosos não está bem definida. Este achado tem sido atribuído a uma secreção inapropriada do Hormônio Antidiurétido (HAD), embora ainda não tenha sido evidenciado um aumento dos níveis plasmático deste hormônio nestes pacientes. Desta forma, este trabalho visa investigar o efeito da Fluoxetina sobre o rim e mais especificamente se ela teria um efeito direto sobre o Ducto Coletor Medular Interno (DCMI) de ratos normais: 1) Estudos in vivo- 10 ratos foram suplementados com aplicações intraperitoniais diárias de 10mg/kg de Fluoxetina. Após 10 dias os animais foram sacrificados e o sangue e os rins foram coletados para posterior análise. 2) Estudos in vitro- a) estudos com a técnica de Imunoblotting para avaliar a expressão da proteína da Aquaporina 2 (AQP2) em ratos suplementados e em suspensão de túbulos de DCMI de 10 ratos normais incubados com 10-7M de Fluoxetina por 30 min. b) estudos com microperfusão de segmentos isolados do nefron- a permeabilidade osmótica à água (Pf, mm./sec) foi determinada em DCMI perfundidos de ratos normais(n=6) com a técnica standart, na presença de10-7M de Fluoxetina. Resultados: 1) Os estudos in vivo mostraram que o peso caiu de 179±1,28g para 158±1,15g (p<0,0001), o Na plasmático caiu de 139,3±0,78mEq/l para 134,9±0,5mEq/l (p<0,0001) e não houve alterações do K e do HAD plasmáticos. 2) Os estudos in vitro-a) a análise densitométrica dos ensaios com imunoblotting mostraram um aumento da expressão da proteína da AQP2 de 40%, ambos, em ratos suplementados (cont-99,6± 5,2 vs Fx 145,6±16,9, p< 0,05) e em frações de membrana da suspensão de túbulos incubados com Fluoxetina (cont-100,0±3,5.vs 143,0±2,0, p<0,01). b) A Fluoxetina aumentou a Pf nos DCMI, na ausência de HAD de 7,24±2,07 para Fx- 15,77±3,25 (p<0,01). Em resumo, nossos dados revelaram que a Fluoxetina determinou uma diminuição do peso corporal e do nível plasmático de Na sem alterar os níveis plasmáticos de K e HAD e ocasionou um aumento da expressão da proteína da AQP2 e um aumento da permeabilidade à água nos DCMI, levando-nos à conclusão de que o efeito direto da Fluoxetina no DCMI, aumentando a reabsorção de água, pode ser responsável pela hiponatremia encontrada nos pacientes idosos com depressão que fazem uso desta droga. / The pathogenesis of the hyponatremia after Fluoxetine(Fx) supply in elderly is not well understood. This event has been attributed to an inappropriate antidiuretic hormone secretion although the vasopressin enhanced plasma level has not been demonstrated yet in these pacients. Thus, this experiment was designed to investigate the effect of Fx on the kidney and more specifically if it would have a direct effect in the inner medullary collecting duct (IMCD) from normal rats: 1) in vivo study- 10 rats were supplied daily with i.p. injections of Fx 10 mg/kg. After five days, the rats were sacrificed and blood and kidneys were collected. 2) in vitro studya) Immunobloting studies for AQP2 protein expression, in IMCD from supplied rats and in IMCD tubules suspension from 10 normal rats incubated with mm./sec) Fx. by 30 min. b) Microperfusion studies- the osmotic water permeability (Pf, mm./sec) was determined in normal rats IMCD(n=6) isolated and perfused by the standart methods.Fx (10-7M) was added to the bath fluid. Results: In vivo study showed that the weight decreased from 179±1.28g to 158±1.5g(p<0.0001); the Na+ plasma level decreased from 139.3±0.78mEq/l to 134.9±0.5mEq/l(p<0.0001), the K+ and the ADH plasma level remained unchanged. In vitro study- a) the densitometric analysis of the immunobloting essays showed an increase in AQP2 protein abundance of about about 40%, both, in supplied rats (cont-99.6± 5.2 vs Fx 145.6±16.9, p< 0.05), and in membrane fraction extracted from IMCD tubule suspension incubated with Fx ( cont-100.0±3.5.vs 143.0±2.0,p<0.01). b) Fx increased the Pf in IMCD in absence of vasopressin from the control period- 7.24±2.07 to Fx- 15.77±3.25 (p<0.01). In summary, our data revealed that, after Fx, weight, and plasma Na+ level decreased, the plasma K+ and ADH levels remained unchanged, whereas the AQP2 protein abundance and the water absorption in IMCD increased, leading us to conclude that the direct effect of Fx in the IMCD, could account for the hyponatremia produced by this drug in depressed elderly.
125

Eszopiclone Facilitation of the Antidepressant Efficacy of Fluoxetine Using a Social Defeat Stress Model

Brown, Russell W., Noel, Daniel M., Smith, Jessica J., Smith, Meredith L., Huggins, Kimberly N., Szebeni, Katalin, Szebeni, Attila, Duffourc, Michelle, Chandley, Michelle, Ordway, Gregory A. 01 October 2011 (has links)
This study analyzed the interaction of the sleep aid eszopiclone (ESZ) and antidepressant fluoxetine (FLX) on social defeat stress (SDS) in the mouse. Beta adrenoreceptors, brain-derived neurotrophic factor (BDNF) and cAMP response element binding protein (CREB) expression in the hippocampus and frontal cortex were also analyzed. Subjects were adult male 'intruder' C57/B6 mice that were exposed to a retired 'resident' male breeder ICR mouse in this animal's home cage for a 5 min period for each of 10 consecutive days, and the resident established physical dominance. The following day, all animals were assigned to one of four drug treatment groups, and treatment was given for up to 18 days: vehicle, ESZ only (3mg/kg), FLX (10mg/kg) only, or ESZ+FLX. A social interaction test was given on days 1, 5, 10, and 15 of drug treatment to assess SDS. Results showed that the ESZ+FLX group spent less time in avoidance zones during the interaction test at days 1 and 5, and more time in the interaction zone at day 5 compared to defeated mice given vehicle. All drug treatment groups spent more time in the interaction zone compared to defeated mice given vehicle on day 1 as well as day 10. SDS completely dissipated by the fourth interaction test according to both behavioral measures. Neurochemically, SDS did not produce changes in any marker analyzed. This study shows the combination of ESZ and FLX alleviated SDS, but a neurochemical correlate remains elusive.
126

Benign Course in a Child With a Massive Fluoxetine Overdose

Feierabend, R. H. 01 September 1995 (has links)
The selective serotonin reuptake inhibitors appear to have a much wider margin of safety than most other classes of antidepressants. Although there is limited experience with acute overdoses of fluoxetine alone, few serious adverse effects have been reported. There has been almost no experience, however, with significant fluoxetine overdoses in children. This report describes the accidental ingestion of as much as 43 mg/kg of fluoxetine by a 4-year-old child. In this case, serum blood levels of the drug and its major metabolite were consistent with a large ingestion and are among the highest reported in the medical literature. Toxic effects were relatively mild and consisted of a brief spell of unresponsiveness, sinus tachycardia, and moderate psychomotor agitation and dyskinesia. Supportive care was provided and the child recovered completely.
127

Studies on the Pathophysiology of Cancer-Induced Depression

Nashed, Mina G. 27 May 2016 (has links)
Despite the lack of robust clinical response, treatment strategies for cancer-induced depression (CID) are currently limited to those developed for non-cancer-related depression. The work presented in this dissertation conceptualizes CID as a pathophysiologically distinct form of depression. To investigate CID at the most basic level, we first developed a preclinical model that was validated by comparison to an established model of stress-induced depressive-like behaviours. The positive control model was developed by chronically treating female BALB/c mice with oral corticosterone (CORT). The CID model was developed using subcutaneous inoculation with 4T1 mammary carcinoma cells. Anhedonia, behavioural despair, and dendritic atrophy in the medial prefrontal cortex (mPFC) were observed in both models. Similar to many human cancer cell lines, 4T1 cells were shown to secrete significant amounts of glutamate, which was markedly attenuated using the system xc- inhibitor sulfasalazine (SSZ). In CID mice, oral treatment with SSZ was at least as effective as fluoxetine, a popular clinical antidepressant, at preventing depressive-like behaviours. This effect was primarily attributable to intact SSZ, rather than its anti-inflammatory metabolite. RNA-sequencing was performed on hippocampal samples from CID and CORT animals. Analysis of differential expressed genes (DEGs) revealed significant overlap between the two models. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and biological process gene ontologies (GO:BP) terms related to ion homeostasis and neuronal communication were enriched for both models. CID was associated with additional DEGs that were not identified in the CORT model. These DEGs were enriched in KEGG pathways and GO:BP terms related to neuronal development, intracellular signalling cascade, learning, and memory. These studies suggest that CID may involve a distinct aetiology, and that glutamate secretion by cancer cells presents a viable target for antidepressant treatment. The development of mechanism-based therapeutics for CID will dramatically improve the quality of life for cancer patients. / Thesis / Doctor of Philosophy (PhD) / Cancer patients are at a high risk of developing depression. In addition to the psychological stress caused by a cancer diagnosis, there is evidence that cancer causes depression through biological pathways. To investigate these pathways, a mouse model of cancer-induced depression (CID) was developed. This model showed comparable behavioural and structural brain deficits to those observed in a stress model of depression. Cancer cells secrete elevated levels of glutamate, a signalling molecule that is involved in depression. In CID mice, inhibiting glutamate release had an antidepressant effect similar to that of fluoxetine, a standard clinical antidepressant. A genetic analysis on brain samples from the CID model revealed significant overlap with the stress model of depression. CID mice had additional changes relevant to learning, memory, and brain cell development that were not detected in the stress model. A better understanding of CID will lead to better treatment strategies developed specifically for cancer patients.
128

PLASTICITY MECHANISMS IN VISUAL CORTEX: ANIMAL MODELS AND HUMAN CORTEX / MECHANISMS OF REINSTATED PLASTICITY

Beshara, Simon P January 2016 (has links)
A holy grail in neuroscience is being able to control plasticity to facilitate recovery from insult in the adult brain. Despite success in animal models, few therapies have translated from bench to bedside. This thesis is aimed at addressing 2 major stumbling blocks in translation. The first gap is in our understanding of the mechanisms of plasticity-enhancing therapies, and the second is in our understanding the relevance of those mechanisms for human development. In chapters 2 and 3, I address the first gap by asking whether fluoxetine, a selective serotonin reuptake inhibitor, which reinstates juvenile-like plasticity in adult animals, reinstates a juvenile-like synaptic environment. We found evidence to suggest that fluoxetine is neuroprotective, as it rescued all of the MD-driven changes, but surprisingly we found no evidence that fluoxetine recreated a juvenile-like synaptic environment, with the exception of Ube3A. Ube3A is necessary for critical period plasticity, indicating that Ube3A may play a crucial in enhancing plasticity in the adult cortex. In chapter 4, I address whether D-serine, an amino acid that has similar effects to fluoxetine in terms of both plasticity and anti-depression, shares a common neurobiological signature with fluoxetine. I found that D-serine’s effects were strikingly similar to fluoxetine, with respect to markers of the E/I balance, indicating that it may be an effective alternative to fluoxetine. In chapter 5, I address the second gap by studying the development of 5 glutamatergic proteins in human V1. Some changes occurred early, as would be predicted from animals studies, while other changes were protracted, lasting into the 4th decade. These results will help guide the use of treatments, like fluoxetine, which effect glutamatergic proteins. iv Together the findings in this thesis significantly advances our understanding of the mechanisms involved in restating plasticity in the adult cortex, and their relevance to humans. / Dissertation / Doctor of Philosophy (PhD) / Neurons change to rewire, adapt, and recover. This plasticity is greatest early in development, so much research has focused on bringing it back in adults. There has been amazing progress in animal models, but this has not translated to humans. Two reasons for this are that we do not fully understand the mechanisms of these treatments in animals or whether those mechanisms are relevant for humans. My thesis addresses this by studying how 2 treatments, fluoxetine and D-serine, affect proteins that are important for plasticity, and how those proteins develop in the humans. I found that these treatments are neuroprotective, but do not recreate a younger state. One interesting standout is an increase in Ube3A, which is essential for juvenile plasticity. I also found that much of human development is similar to animals, but the time course for some proteins is uniquely prolonged in humans. These findings have implications for the use of plasticity-enhancing treatments at different ages.
129

The Use of Doublecortin to Quantify the Effects of Pharmacological Treatment on Neurogenesis and Functional Recovery after Stroke

Hensley, Amber Lee 13 May 2016 (has links)
No description available.
130

The Timing of Fluoxetine, Simvastatin and Ascorbic AcidAdministration in a Post-Ischemic Stroke Environment AffectsInfarct Volume and Hemorrhagic Transformation Frequency

Verma, Neal R. 03 June 2016 (has links)
No description available.

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