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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.
51

Desenvolvimento e Validação de Método Indicativo de Estabilidades Para Comprimidos Revestidos de Metildopa

SANTOS, Bruno Aires dos 30 May 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-06-28T14:51:48Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) UNIVERSIDADE FEDERAL DE PERNAMBUCO (Salvo Automaticamente)_correto.pdf: 1889034 bytes, checksum: eb0752322509ac8a41b42b336e30870a (MD5) / Made available in DSpace on 2016-06-28T14:51:48Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) UNIVERSIDADE FEDERAL DE PERNAMBUCO (Salvo Automaticamente)_correto.pdf: 1889034 bytes, checksum: eb0752322509ac8a41b42b336e30870a (MD5) Previous issue date: 2014-05-30 / A metildopa (a-metil-3, 4-dighidro-l-fenilalanina) é um agente hipotensor de ação central, é uma pró-droga, que exerce sua ação anti-hipertensiva através de um metabólito ativo. A estabilidade é um importante parâmetro para avaliar a segurança, eficácia e qualidade exigidas para o registro sanitário de produtos farmacêuticos. Vários países publicam diretrizes para estabilidade farmacêutica. No Brasil, estes estudos devem ser conduzidos segundo o Guia para a Realização de Estudos de Estabilidade, publicada na resolução - RE n.01 de 29 de julho de 2005 e a RDC 58 de 20 de dezembro de 2013 que estabelece parâmetros para a notificação, identificação e qualificação de produtos de degradação em medicamentos com substâncias ativas sintéticas e semissintéticas, classificados como novos, genéricos e similares e dá outras providências. O objetivo desse trabalho foi desenvolver um método indicativo de estabilidade para comprimidos revestidos de metildopa 500mg, avaliando a especificidade e a seletividade deste método. Para avaliação da especificidade e seletividade do método foram mantidas amostras da metildopa matéria-prima, comprimido revestido 500mg e placebo nas seguintes condições de estresse: hidrólises (ácida, básica e neutra), oxidação e temperatura; as amostras também foram submetidas ao teste de fotoestabilidade. A seletividade do método também foi demonstrada após realização de testes com o padrão primário de metildopa contaminado com a impureza 3-O-metil-metildopa. Os resultados foram analisados segundo dados gerados por cromatografia líquida de alta eficiência (CLAE) com detector de arranjo de diodos (DAD). A 3-O-metildopa apresenta tempo de retenção relativo (TRR) de 1,37 frente à metildopa. A metildopa mostrou-se estável nas hidrólises neutras e ácida menos concentradas bem como na degradação térmica, oxidativa e na fotoestabilidade. Apresentou um decaimento muito acentuado nas condições básicas (NaOH 0,1 e 1,0M), sendo inadequado para o estudo de métodos indicativos de estabilidade como indica a RDC 58 de 2013. A condição mais severa da hidrolise ácida (HCl 5,0M) apresentou um teor de 77,80% para a matéria-prima e 82,99% para o comprimido revestido em comparação com o padrão de trabalho após 72 horas de estudo, ambos apresentaram um pico de degradação com TRR de aproximadamente 2,00. Na condição de hidrólise alcalina menos concentrada (NaOH 0,01M) apareceram produtos de degradação tanto na matéria-prima como para o comprimido revestido de metildopa, porém, o pico que apresenta área significativa apresenta TRR de 0.38 e o teor do fármaco foi de 73,49% para a matéria-prima e 74,48% para o comprimido revestido em comparação com o padrão de trabalho após 72 horas de estudo. Através das análises dos resultados obtidos utilizando as ferramentas de integração e de análise espectral para avaliação da similaridade e pureza dos picos, verifica-se que o método utilizado consegue detectar os produtos de degradação que venham a surgir durante os estudos de estabilidade. O método posteriormente foi validado utilizando como referências a RE 899 de 2003 e a norma técnica da ICH Q2 R1. O método desenvolvido e validado foi utilizado no estudo de estabilidade de um comprimido revestido de metildopa 500mg similar constante no mercado brasileiro, apresentando resultados dentro da especificação exigida para o produto. / Methyldopa (a-methyl-3,4-dihydro-l-phenylalanine) is a centrally acting antihypertensive agent, is a prodrug, which exerts its antihypertensive action through an active metabolite. Stability is an important parameter to evaluate the safety, efficacy and quality required for sanitary registration of pharmaceutical products. Several countries publish guidelines for pharmaceutical stability. In Brazil, the stability studies should be conducted according to the guide on conducting stability studies, published in the resolution RE 01 of July 29, 2005 and RDC 58 of December 20, 2013 laying down parameters for notification, identification and qualification of degradation products in medicine with synthetic and semi synthetic active substances classified as new, generic and similar and other measures. The aim of this study was to develop a stability indicating method for coated tablets 500mg of methyldopa following and evaluating the specificity and selectivity of this method. To assess the specificity and selectivity of the method of methyldopa samples were stored raw material, coated tablet 500mg and placebo in the following stress conditions: hydrolysis (acidic, basic and neutral), oxidation, light and temperature. The selectivity of the method was demonstrated after testing with the primary pattern methyldopa contaminated with impurity 3-O-methyl-methyldopa. The results were analyzed according to data generated by high performance liquid chromatography (HPLC) with diode array detector (DAD). 3-O-methyl-methyldopa has RRT 1.37 front methyldopa. Methyldopa was stable in neutral and acidic hydrolysis less concentrated as well as thermal, oxidative degradation and photostability. Showed a dramatic decay in basic conditions (NaOH 0,1 and 1,0M) and unsuitable for the study of stability indicating methods as shown in the RDC 58/ 2013. The most severe conditions of acid hydrolysis (5,0M HCl) showed a content of 77.80 % for the raw material and 82.99 % for the coated tablet compared the standard of work after 72 hours of study, both showed a peak of degradation with TRR approximately 2,00. In the condition of less concentrated alkaline hydrolysis (0,01M NaOH) appeared both in the degradation products as raw material for the coated tablet methyldopa, however, the peak that shows significant area RRT 0,38 and shows content of the drug was 73,49% for raw and 74,48% for the coated tablet compared the standard of work after 72 hours of study. Through the analysis of the results obtained using the tools of integration and spectral analysis for assessing similarity and purity of the peaks, it is found that the method can detect possible degradation products that arise during the stability studies . The method was subsequently validated using as references to RE 899 2003 and the technical standards of the ICH Q2 R1. The developed and validated method was used on a tablet stability study coated methyldopa 500mg similar constant in the Brazilian market, presenting results within the specification required for the product.
52

Estudo do perfil serotoninérgico no hipocampo de pacientes com epilepsia do lobo temporal / Study of serotonergic profile in temporal lobe epilepsy patients\' hippocampus

Natascha Cardoso da Fonseca 01 October 2018 (has links)
A epilepsia é a condição crônica mais prevalente dentre as doenças neurológicas graves, associada com taxas significativas de morbidade e mortalidade. Pacientes com epilepsia farmacorresistente possuem uma taxa de mortalidade 2 a 3 vezes maior que indivíduos sem epilepsia. A epilepsia do lobo temporal (ELT) é a principal causa de epilepsia farmacorresistente nos adultos e também o protótipo da epilepsia cirurgicamente tratável, portanto, com maior acessibilidade para estudo de possíveis mecanismos epileptogênicos. Esclerose hipocampal (EH) é o achado neuropatológico mais comum em pacientes com ELT. Evidências, baseadas em experimentos animais e estudos em humanos, sugerem que as vias serotoninérgicas desempenham um importante papel na epileptogênese. Pacientes com ELT, causadas pela EH, apresentam maior prevalência de transtornos do humor e psicose contribuindo para uma pior qualidade de vida, com consequente impacto negativo nas respostas terapêuticas farmacológicas e cirúrgicas. Além disso, alguns estudos sugerem a existência de um mecanismo patogênico operante comum entre estas condições. Portanto, esta é um importante variável para análise. O objetivo desse estudo foi correlacionar as variáveis clínicas da epilepsia e a presença de transtornos psiquiátricos coexistentes com a concentração de serotonina (5-HT), a densidade dos receptores serotoninérgicos e a densidade do transportador serotoninérgico (5-HTT) no hipocampo dos pacientes com ELT-EH, que foram submetidos à cirurgia devido à presença de epilepsia farmacorresistente. Foram avaliadas amostras de 44 hipocampos de pacientes cirurgicamente tratados para ELT-EH. A concentração de 5-HT foi avaliada por cromatografia líquida de alta eficiência (HPLC) com detecção por fluorescência. 5-HTT e os receptores serotoninérgicos 5-HT1A, 5-HT2A, 5-HT6 e 5-HT7 foram avaliados por Western Blot. Níveis mais baixos de concentração de 5-HT estiveram associados com a presença de crises TCG (Wilcoxon-Mann-Whitney; p = 0.019). A densidade aumentada do receptor 5-HT1A esteve associada com maior duração da epilepsia (coeficiente de correlação de Spearman: p = 0.040) e a densidade diminuída do receptor 5-HT6 esteve associado com presença de EME (Wilcoxon-Mann-Whitney: p = 0.0027). A densidade dos receptores 5-HT2A e 5-HT7 e do 5-HTT não estiveram associadas com variáveis clínicas da epilepsia. A concentração de 5-HT, a densidade dos receptores e a densidade de 5-HTT não estiveram associadas à presença dos transtornos psiquiátricos neste grupo de pacientes. Nossos achados sugerem que as vias serotoninérgicas estão associadas com mecanismos de epileptogênese. Não foi evidenciado associações entre as vias serotoninérgicas e a presença de comorbidades psiquiátricas neste grupo de pacientes com ELT-EH / Epilepsy is the most prevalent neurological condition and it is associated with significative morbidities and mortalities rates. Patients with refractory epilepsy have a 2- to 3-fold higher mortality rate than people without epilepsy. Temporal lobe epilepsy (TLE) is the most common form of adult drug-resistant epilepsy. It is also the prototype of a surgically treatable epilepsy and because of that it is the most accessible for studies focused in epileptogenesis. Hippocampal sclerosis (HS) is the most common neuropathological finding in patients with TLE. Evidences from experimental, clinical and image studies suggest that the serotonergic system play an important role in epileptogenesis. Patients with TLE-HS have a higher prevalence of mood disorder and psychosis contributing for a worse quality of life with and consequent negative impact in pharmacological and surgical responses. Furthermore, studies suggest a common pathogenic mechanism operant in both conditions. Therefore, this is an important analytical variable. The objective of this study was to correlate clinical variables of epilepsy and the presence of psychiatric disease with serotonin (5-HT) concentration, serotonergic receptor density and serotonergic transporter (5-HTT) density in the hippocampus of TLE-HS patients submitted for surgery due to refractory epilepsy. It was analyzed 44 hippocampal tissue samples from surgical treated TLE-HS patients. 5-HT concentration was assessed by high pressure liquid chromatography (HPLC) with fluorescence detection. 5-HTT and serotonergic receptors 5-HT1A, 5-HT2A, 5-HT6 and 5- HT7 were assessed by Western Blotting. Lower levels of 5-HT concentration were associated with the presence of generalized tonic-clonic seizures (Wilcoxon-Mann-Whitney; p = 0.019). A higher 5-HT1A receptor density was associated with longer epilepsy duration (Spearman correlation coefficient: p = 0.040). Lower 5-HT6 receptor density was associated with the presence of status epilepticus (Wilcoxon-Mann-Whitney: p = 0.0027). 5-HT2A receptor, 5- HT7 receptor and 5-HTT densities were not associated with clinical variables of epilepsy. 5-HT concentration, serotonergic receptors and transporter densities were not associated with the presence of psychiatric disease in this group of patients. Our findings suggest that the serotonergic pathways are associated with epileptogenesis mechanisms. It was not evidenced any association between serotonergic pathways and psychiatric comorbidities in this group of TLE-HS patients
53

Avaliação da adesão à terapia anti-hipertensiva na hipertensão resistente pelos métodos direto e indiretos / Adherence assessment to antihypertensive therapy in resistant hypertension by direct and indirect methods

Patricia Cardoso Alarcon Hori 31 August 2018 (has links)
Introdução: A má adesão à terapia anti-hipertensiva medicamentosa é uma causa frequente de dificuldade de controle da pressão arterial. A prevalência de hipertensão resistente (HR) verdadeira não é conhecida pela dificuldade de estimar de maneira precisa a adesão ao tratamento medicamento anti-hipertensivo prescrito na prática clínica. Objetivos: Comparar os métodos direto e indiretos de avaliação da adesão ao tratamento anti-hipertensivo em pacientes com HR, medir a adesão ao tratamento medicamentoso pelo método direto em pacientes com HR, estimar a prevalência de HR verdadeira e identificar características clínico-demográficas associadas à adesão. Métodos: Foram recrutados pacientes com HR, definida como Pressão Arterial (PA) de consultório não controlada (PA Sistólica > 140 mmHg e/ou PA Diastólica > 90 mmHg), usando três ou mais classes de anti-hipertensivos em doses plenas, sendo um diurético; ou com PA de consultório controlada (PA Sistólica < 140 mmHg e PA Diastólica < 90 mmHg), usando quatro ou mais classes de anti-hipertensivos. O método direto de avaliação da adesão consistiu na análise de amostras de urina contendo os anti-hipertensivos prescritos pela técnica de cromatografia líquida de alta pressão (High Pressure Liquid Chromatography Mass - HPLC). As análises foram feitas em quatro oportunidades diferentes, com intervalo médio de 30 dias entre as coletas. Para comparação, foram realizados concomitantemente cinco métodos indiretos de avaliação da adesão: contagem de comprimidos (CTG CP), questionário de adesão MMAS-8, impressão médica, avaliação do farmacêutico e do próprio paciente. Foram considerados pacientes aderentes pelo método direto aqueles que apresentaram todos os anti-hipertensivos prescritos em pelo menos 3 das 4 amostras de urina coletadas; consumo >= 80% dos comprimidos pela CTG CP; pontuação >= 7 no questionário MMAS-8 e nota >= 4 nas avaliações médica, farmacêutica e do próprio paciente. Para a avaliação da concordância entre os métodos foi utilizado o coeficiente de correlação de Kappa (CCK). Resultados: 50 pacientes com HR foram recrutados: 68% mulheres, com idade média de 55,1 anos (± 8,2 anos), índice de massa corpórea 29 (± 3,3 kg/m2), PA de Consultório 149/86 mmHg (± 26/15 mmHg), PA de 24 horas pela Monitoração Ambulatorial da Pressão Arterial (MAPA) de 127/82 mmHg (± 19/11 mmHg) e número de classes de anti-hipertensivos prescritos por paciente de 4,6 (± 0,7). A frequência de não adesão encontrada pelo método direto foi de 66%. Classificando os pacientes de acordo com a adesão e o controle da PA pela MAPA, 42% foram considerados pseudo-hipertensos resistentes por má adesão e apenas 18% hipertensos resistentes verdadeiros. A concordância entre os métodos avaliados foi baixa de acordo com o CCK, variando de não existente [métodos CTG CP (-0,040), impressão farmacêutica (-0,040) e do paciente (-0,132)] a mínima [questionário MMAS-8 (0,055) e impressão médica (0,126)]. Nenhuma das características clínicodemográficas avaliadas mostrou qualquer associação com a adesão pelo método direto. Conclusão: A prevalência de não adesão é alta em pacientes com HR, sendo esta, provavelmente, a principal causa de resistência ao tratamento antihipertensivo. Os métodos de adesão indiretos avaliados não apresentaram concordância com o método direto, devendo ser questionável sua utilização como ferramenta de medida de adesão na prática clínica / Background: Poor adherence to antihypertensive therapy is a frequent cause of resistant hypertension (RH). The real prevalence of true RH is still unknown due to the difficulty to accurately estimating adherence to the antihypertensive drug in clinical practice. Objective: Compare the direct and indirect methods of assessing adherence to hypertension treatment, measure the adherence to the drug treatment by the direct method in patients with RH, estimate the prevalence of true RH and to identify clinical and demographic characteristics associated with adherence. Methods: Patients with RH were enrolled: office blood pressure (BP) above goal (systolic BP > 140mmHg and/or diastolic BP > 90mmHg), taking three or more antihypertensive drugs of different classes at optimal dose, which one of them should be a diuretic; or office BP below goal (systolic BP < 140mmHg and/or diastolic BP< 90mmHg), taking four or more antihypertensive drugs. Adherence was assessed by direct method of High Pressure Liquid Chromatography (HPLC) analysis for antihypertensive drugs, in 4 different urine samples, in a 30-day interval. For comparison, five indirect methods of adherence assessment were performed simultaneously: pill count, MMAS-8 questionnaire, patient self-report, physician judgement and pharmaceutical judgement. Patient was considered adherent by direct method if every antihypertensive drug was found in 3 urine samples at least; if he consumed 80% of prescribed medication at least; if he reached score >= 7 on the MMAS-8; >= 4 on self-report, physician judgement and pharmaceutical judgement. Kappa correlation coefficient (KCC) was performed to evaluate the agreement between the methods. Results: 50 patients with HR were enrolled: 68% women, mean age 55,1 ± 8,2 years, body mass index 29 ± 3,3 kg/m2, office BP 149/86 ± 26/15 mmHg, mean 24 hs by Ambulatory Blood Pressure Monitoring (ABPM) 127/82 ± 19/11 mmHg and average of antihypertensive druhs prescribed 4,6 ± 0,7 classes. 66% of patients were non-adherent by direct method: 42% classified as pseudoresistant hypertensive patients due to low adherence and only 18% as true resistant hypertensive. Agreement between methods was low according to KCC, ranging from non-existent [pill count (-0,040), pharmaceutical judgement (-0,040) and self-report (-0,132)] to minimum [MMAS-8 questionnaire (0,055) and physician judgement (0,126)]. There is no association between clinical and demographic characteristics and adherence by direct methods. Conclusion: The prevalence of non-adherence is high in patients with RH, which is probably the main cause of resistance to antihypertensive treatment. The indirect adherence methods evaluated did not show agreement with the direct method, and its use as a tool to measure adherence in clinical practice should be questionable
54

Kinetika fotodegradace benzo[a]pyrenu a identifikace jeho produktů / Kinetics of benzo[a]pyrene destruction and identification of its products

Ryšavý, Jan January 2010 (has links)
This diploma thesis is focused on the study of conditions of benzo[a]pyrene, one of the major contaminant of foods, photodegradation under different conditions (solvents with different polarity, light sources, presence of antioxidants). In another part of the thesis, the degradation process of benzo[a]pyrene at various concentrations was studied, in order to characterise the kinetic aspects of photoinduced degradation. The attempt to identify the products of benzo[a]pyrene photodegradation was performed involving methods of gas chromatography and high performance liquid chromatography coupled with mass detectors, as well.
55

Analiza komine grožđa i dijetetskih suplemenata na bazi grožđa i japanskog troskota i ispitivanje uticaja suplementacije kod eksperimentalnih životinja / Analysis of grape pomace and dietary supplements based on grapes and Polygonum cuspidatum and examination of the effect of supplementation in experimental animals

Ćućuz Veljko 22 June 2020 (has links)
<p>Doktorsku disertaciju čine tri celine kojima je zajednički element ispitivanje fenola, u pogledu njihovog sadržaja i dostupnosti u dijetetskim suplementima na bazi grožđa i japanskog troskota, ispitivanja uticaja suplementacije kod eksperimentalnih životinja, odnosno mogućnosti ekstrakcije fenolnih jedinjenja iz komine grožđa. Osnovni ciljevi prvog dela bili su ispitivanje bezbednosti i kvaliteta 14 suplemenata na bazi grožđa i japanskog troskota u pogledu ujednačenosti mase, sadržaja i brzine rastvorljivosti. U drugom delu je radi provere terapijske delotvornosti suplementa koji sadrži čist resveratrol ispitan njegov uticaj na glikemiju i lipidni status eksperimentalnih životinja. Treći deo je obuhvatio analizu pet različitih komina grožđa i razvoj metode ekstrakcije fenola iz odabrane komine kako bi se dobili ekstrakti sa &scaron;to je moguće većim prinosom, koristeći rastvarače koji su bezbedni po ljudsko zdravlje. Rezultati su pokazali da dva od četrnaest suplemenata nisu ispunila zahteve farmakopeje za lekove u pogledu ujednačenosti mase i sadržaja aktivne komponente, dok ni jedan suplement nije ispunio zahteve u pogledu brzine rastvorljivosti aktivne supstance, zbog čega se postavlja pitanje delotvornosti ispitanih suplemenata. Ni kod jednog suplementa nisu kvantifikovani ostaci pesticida ni toksični metali, čime je potvrđena njihova bezbednost. Farmakodinamska ispitivanja na pacovima pokazala su antioksidantna, anti-dijabetska i hipolipidemijska svojstva dijetetskog suplementa na bazi resveratrola, čime je potvrđena njegova delotvornost. Za potvrdu delotvornosti suplementa na ljudima neophodno je sprovesti dobro dizajnirano kliničko ispitivanje na dovoljnom broju ispitanika. Analiza pet različitih komina grožđa pokazala je da ovaj nusprodukt proizvodnje vina sadrži različite fenole, od kojih je samo katehin bio prisutan u značajnoj količini. Kvalitativan i kvantitativan sastav komine značajno varira zavisno od sorte i berbe grožđa, kao i od primenjenog tehnolo&scaron;kog procesa proizvodnje vina. Imajući u vidu sveobuhvatne kriterijume u pogledu efikasnosti ekstrakcije, zaključeno je da su 55% etanol, odnos uzorak / rastvarač 1:40, pH 4,5, T 55&deg;C i vreme od 30 min optimalni eksperimentalni uslovi za ekstrakciju fenola iz komine grožđa. U zavisnosti od osnovnog cilja procesa ekstrakcije ovi parametri se mogu lako modifikovati. Vi&scaron;estruke su mogućnosti za iskori&scaron;ćenje komine grožđa, a jedan od njih bi mogla biti i da se koristi kao sirovina za izradu dijetetskih suplemenata.</p> / <p>The dissertation consists of three parts with a common element &ndash; testing phenols in terms of content and availability in grape and Polygonum cuspidatum-based dietary supplements, testing the supplement&rsquo;s impact on experimental animals and the possibility to extract phenolic compounds from grape pomace. The primary objectives of the first part were testing safety and quality of fourteen grape and Polygonum cuspidatum-based supplements in terms of uniformity of mass, content and dissolution profile. In the second part, to test the therapeutic efficacy of a supplement containing pure resveratrol, its effect on the glycemia and lipid profile of experimental animals was examined. The third part covers the analysis of five different grape pomaces and the development of a phenol extraction method from the selected grape pomace to obtain extracts with the highest possible yield, using solvents that are safe for human health. The results showed that two out of fourteen supplements have not met the Pharmacopoeia requirements in terms of uniformity of mass and active substance content, while no supplement has met requirements in terms of dissolution test of the active substance, which raises the question of the effectiveness of the tested supplements. No pesticide or heavy metal residues were quantified in any of the supplements which confirms their safety. Pharmacodynamic testing on rats has shown antioxidant, antidiabetic and hypolipidemic properties of the resveratrol-based dietary supplement which confirms its efficacy. In order to confirm the supplement efficacy on people, it is necessary to conduct a well-designed clinical trial on a sufficient number of human participants. The analysis of five different grape pomaces revealed that this byproduct of vine production contains different phenols, and only catechin was present in significant amounts. The qualitative and quantitative composition of grape pomace varies significantly depending on grape variety and harvesting as well as on the technological process that was applied in vine production. Considering the comprehensive criteria in terms of extraction efficacy, it was concluded that optimal experimental conditions for the extraction of phenol from grape pomace include 55% ethanol, sample/solvent ratio 1:40, pH 4.5, T 55&deg;C for 30 minutes. Depending on the primary objective in the extraction process, these parameters can be easily modified. There are multiple possibilities for utilizing grape pomace and one of them could be as raw material in production of dietary supplements.</p>
56

Ketoprofen Tissue Permeation in Swine Following Cathodic Iontophoresis

Panus, Peter C., Ferslew, K E., Tober-Meyer, B, Kao, R. L. 01 January 1999 (has links)
BACKGROUND AND PURPOSE: Pharmacokinetic assessment of drug tissue permeation following iontophoresis is limited. The depth of ketoprofen tissue permeation following cathodic iontophoresis (4 mA, 40 minutes) and the stereoselectivity of drug delivery were examined in this study. SUBJECTS: Ketoprofen (750 mg) was iontophoresed onto one porcine medial thigh, with passive drug permeation conducted on the other thigh. METHODS: Skin, subcutaneous fascia, and muscle biopsies from the drug delivery sites were harvested and stored separately, and the "R" and "S" ketoprofen enantiomers were determined. Results. Iontophoretic and passive applications yielded equivalent total ketoprofen concentrations in the skin and fascia. In contrast, multivariate analysis demonstrated that the ketoprofen concentration in the first centimeter of muscle following iontophoresis was greater than the drug concentration in the deeper underlying muscle layers and greater than that delivered to any muscle layer following passive delivery. No transcutaneous stereoselective delivery) of ketoprofen was detected. CONCLUSION AND DISCUSSION: Compared with passive delivery, iontophoresis enhances nonstereoselective ketoprofen permeation into the fascia-muscle interface. With delivery to deeper tissue sites, however, there is no apparent enhancement over passive application.
57

Cocrystalization and simultaneous agglomeration using hot melt extrusion

Dhumal, Ravindra S., Kelly, Adrian L., York, Peter, Coates, Philip D., Paradkar, Anant R January 2010 (has links)
No / PURPOSE: To explore hot melt extrusion (HME) as a scalable, solvent-free, continuous technology to design cocrystals in agglomerated form. METHODS: Cocrystal agglomerates of ibuprofen and nicotinamide in 1:1 ratio were produced using HME at different barrel temperature profiles, screw speeds, and screw configurations. Product was characterized for crystallinity by XRPD and DSC, while the morphology was determined by SEM. Dissolution rate and tabletting properties were compared with ibuprofen. RESULTS: Process parameters significantly affected the extent of cocrystallization which improved with temperature, applied shear and residence time. Processing above eutectic point was required for cocrystallization to occur, and it improved with mixing intensity by changing screw configuration. Product was in the form of spherical agglomerates, which showed directly compressible nature with enhanced dissolution rate compared to ibuprofen. This marks an important advantage over the conventional techniques, as it negates the need for further size modification steps. CONCLUSIONS: A single-step, scalable, solvent-free, continuous cocrystallization and agglomeration technology was developed using HME, offering flexibility for tailoring the cocrystal purity. HME being an established technology readily addresses the regulatory demand of quality by design (QbD) and process analytical technology (PAT), offering high potential for pharmaceuticals.
58

In vivo activation of the hypoxia-targeted cytotoxin AQ4N in human tumor xenografts

Williams, K. J., Albertella, M. R., Fitzpatrick, B., Loadman, P. M., Shnyder, S. D., Chinje, E. C., Telfer, B. A., Dunk, C. R., Harris, P. A., Stratford, I. J. January 2009 (has links)
AQ4N (banoxantrone) is a prodrug that, under hypoxic conditions, is enzymatically converted to a cytotoxic DNA-binding agent, AQ4. Incorporation of AQ4N into conventional chemoradiation protocols therefore targets both oxygenated and hypoxic regions of tumors, and potentially will increase the effectiveness of therapy. This current pharmacodynamic and efficacy study was designed to quantify tumor exposure to AQ4 following treatment with AQ4N, and to relate exposure to outcome of treatment. A single dose of 60 mg/kg AQ4N enhanced the response of RT112 (bladder) and Calu-6 (lung) xenografts to treatment with cisplatin and radiation therapy. AQ4N was also given to separate cohorts of tumor-bearing mice 24 hours before tumor excision for subsequent analysis of metabolite levels. AQ4 was detected by high performance liquid chromatography/mass spectrometry in all treated samples of RT112 and Calu-6 tumors at mean concentrations of 0.23 and 1.07 microg/g, respectively. These concentrations are comparable with those shown to be cytotoxic in vitro. AQ4-related nuclear fluorescence was observed in all treated tumors by confocal microscopy, which correlated with the high performance liquid chromatography/mass spectrometry data. The presence of the hypoxic marker Glut-1 was shown by immunohistochemistry in both Calu-6 tumors and RT112 tumors, and colocalization of AQ4 fluorescence and Glut-1 staining strongly suggested that AQ4N was activated in these putatively hypoxic areas. This is the first demonstration that AQ4N will increase the efficacy of chemoradiotherapy in preclinical models; the intratumoral levels of AQ4 found in this study are comparable with tumor AQ4 levels found in a recent phase I clinical study, which suggests that these levels could be potentially therapeutic.
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Studium metabolismu vzdušných polutantů a mutagenů 3-nitrobenzanthronu a 2-nitrobenzanthronu / Study of metabolism air pollutants and mutagens 3-nitrobenzanthrone and 2-nitrobenzanthrone

Čechová, Tereza January 2012 (has links)
Nitroaromatic compounds are mutagenic and carcinogenic substances present in environment. Most of nitroaromatic compounds are potent mutagens in bacterial and mammalian systems. They are also carcinogens causing development of tumors, primarily in the liver, lung and mammary glands. 3-Nitrobenzanthrone (3-NBA, 3-nitro-7H-benz [de] anthracene-7-one) is one of the polycyclic aromatic nitro compounds possesing high toxic effects. 3-NBA is an environmental pollutant present in diesel exhaust and was also detected in soil and in rain water. 2-Nitrobenzanthrone (2-NBA, 2-nitro-7H-benz [de] anthracene-7-one) is an isomer 3-NBA, which also occurs as a pollutant in air. Although the 2-NBA is a weakly toxic substance, its high abundance in air could exhibit a high health risk to humans. This thesis investigates the metabolism of 3-NBA and its isomeric derivate, isomer 2 NBA, under anaerobic and aerobic conditions. To study the metabolism of these compounds, microsomal systems isolated from the liver of rats pretreated with Sudanem I, -naphthoflavone, phenobarbital, ethanol and pregnenolon 16-carbonitrile (PCN), the inducers of cytochromes P450 1A, 2B, 2E1 and 3A, were used. We also used mouse models, a control mouse line (wild type WT) and mice with deleted gene of NADPH:CYP reductase in the liver, thus absenting...
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Biološko dejstvo vodenog ekstrakta ploda štavelja (Rumex crispus L., Polygonaceae) / Biological activity of aqueous extract of yellow dock fruit (Rumex crispus L., Polygonaceae)

Jakovljević Dunja 05 July 2019 (has links)
<p>&Scaron;tavelj (Rumex crispus, Polygonaceae) je vi&scaron;egodi&scaron;nja zeljasta biljka, koja predstavlja bogat izvor fenolnih komponenti. Iako se smatra invazivnim korovom, mlado li&scaron;će &scaron;tavelja je jestivo i često se koristi kao salata. Dalje, upotreba plodova &scaron;tavelja opisana je u srpskoj i turskoj narodnoj medicini u lečenju gastrointestinalnih tegoba. Cilj ovog rada bio je procena in vitro i in vivo antioksidantne/prooksidantne i citotoksične aktivnosti, i određivanje eventualnog in vitro antiinflamatornog efekta vodenog ekstrakta ploda Rumex crispus. Ukupan sadržaj flavonoida određen je spektrofotometrijskom metodom. Kvalifikacija i kvantifikacija flavonoida potvrđena je visokoefikasnom tečnom hromatografijom (HPLC). Antioksidantna aktivnost vodenog ekstrakta ploda &scaron;tavelja procenjena je na osnovu in vitro testova: Ferric-reducing antioxidant power (FRAP), sposobnosti ekstrakta da neutrali&scaron;e slobodne radikale NO&bull;, OH&bull; i DPPH&bull; i uticaja na lipidnu peroksidaciju u lipozomima. Citotoksičnost ispitivanog ekstrakta je određena in vitro na tumorskim ćelijskim linijama: humani karcinom cerviksa (HeLa), adenokarcinom (HT-29) i adenokarcinom dojke (MCF7). Takođe, moguća in vivo hepatoprotektivna i antioksidantna svojstva ekstrakta određena su kod oksidativnog stresa izazvanog CCl4 kod eksperimentalnih životinja. Pored toga, proverena je hipoteza u kojoj testiran ekstrakt pokazuje in vivo antiproliferativnu aktivnost kod Ehrlich-ovih (EAC) i Hepatoma AS30D ćelija, merenjem zapremine ascitesa, procenta vijabilnih ćelija i nivoa nekoliko antioksidantnih enzima. Optimizovan in vitro test za određivanje potencijala inhibicije ciklooksigenaze-1 (COX-1) i 12-lipooksigenaze (12-LOX) preduzet je u svrhu procene antiinflamatornog efekta vodenog ekstrakta ploda R. crispus. HPLC analiza otkrila je da je mikvelianin najdominantniji flavonoidni konstituent ekstrakta. Testirani ekstrakt pokazao je potencijalnu antioksidantnu aktivnost rezultujući velikom moći u neutralizaciji slobodnih radikala, i sposobno&scaron;ću da smanji lipidnu peroksidaciju u lipozomima. Rezultati su ukazali na tkivno-selektivnu citotoksičnost ekstrakta ploda R. crispus in vitro. Najizraženija antitumorska aktivnost primećena je prema HeLa i MCF7 ćelijskim linijama. Podaci sugeri&scaron;u da bi se ispitivani ekstrakt mogao smatrati potencijalnim in vivo hepatoprotektivnim i antioksidantnim agensom, sprečavajući oksidativna o&scaron;tećenja jetre. S druge strane, pomenuti ekstrakt može pokazati in vivo prooksidantna svojstva, uzrokujući oksidativni stres u maligno transformisanim EAC i AS30D ćelijama i smanjujući zapreminu ascitesa i udeo vijabilnih ćelija, u poređenju sa kontrolnom grupom. Promene u aktivnosti antioksidantnih enzima su verovatno posledica indukovanog oksidativnog stresa u EAC i AS30D ćelijama, naročito kod pretretiranih životinja. Vodeni ekstrakt ploda &scaron;tavelja pokazao je COX-1, kao i 12-LOX inhibitornu aktivnost, navodeći da bi ispitivani ekstrakt mogao biti antiinflamatorni agens. Vodeni ekstrakt ploda R. crispus ima potencijalnu antioksidantnu, citotoksičnu i antiinflamatornu aktivnost. Ispoljavanje prooksidantnih svojstava predstavlja mogući mehanizam antiproliferativnog efekta ekstrakta.</p> / <p>Curly dock (Rumex crispus, Polygonaceae) is a wild perennial herbaceous plant, which products are described as a rich source of phenolic compounds. Apart from being considered a seriously invasive weed, young leaves of curly dock are edible and often used as salad. Furthermore, the use of its fruits has been described in Serbian and Turkish traditional medicine against stomach complaints. The objectives of this study were to evaluate in vitro and in vivo antioxidant/prooxidant and cytotoxic activities, and to determine an eventual in vitro anti-inflammatory effect of the aqueous extract of Rumex crispus fruits. Total flavonoid content was determined by spectrophotometric method. Qualification and quantification of flavonoids were confirmed using High performance liquid chromatography (HPLC). The aqueous extract of curly dock fruits was evaluated for its antioxidant activity by in vitro assays for Ferric-reducing antioxidant power (FRAP), NO&bull;, OH&bull; and DPPH&bull;-free radical scavenging activities and the influence on lipid peroxidation in liposomes. The cytotoxicity of tested extract was examined in vitro in human cervix carcinoma (HeLa), colon adenocarcinoma (HT-29) and breast adenocarcinoma (MCF7). Also, the potential in vivo hepatoprotective and antioxidant properties of investigated extract were determined on CCl4-induced oxidative stress in experimental animals. Furthermore, the hypothesis that the examined extract might show in vivo antiproliferative activity in Ehrlich carcinoma (EAC) and Hepatoma AS30D cells was tested by measuring volume of ascites, percentage of viable cells and level of several antioxidant enzymes. The optimized in vitro test for determination of cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) inhibition potency was undertaken in order to estimate an anti-inflammatory effect of aqueous extract of R. crispus fruits. HPLC analysis revealed miquelianin as the most abundant flavonoid constituent of the extract. The tested extract might have an antioxidant activity resulting in scavenging of free radicals and ability to decrease lipid peroxidation in liposomes. The results could indicate tissue-selective cytotoxicity of R. crispus fruit extract in vitro. The most prominent antitumor activity was observed towards HeLa and MCF7 cell lines. The data suggested that investigated extract may be considered as potential in vivo hepatoprotective and antioxidant agent due to prevention of the liver injuries induced by oxidative damage. On the other hand, mentioned extract could exhibit in vivo prooxidant property, causing the oxidative stress in malignant transformed EAC and AS30D cells and reducing volume of ascites and percentage of viable cells, in comparison with control group. Changes in activities of antioxidant enzymes might be the results of induced oxidative stress in EAC and AS30D cells, especially in the pretreated animals. The aqueous extract of curly dock fruits showed COX-1, as well as 12-LOX inhibitory activity, suggesting that tested extract might be an anti-inflammatory agent. It could be concluded that aqueous fruit extract of R. crispus might have antioxidant, cytotoxic and anti-inflammatory activities. The prooxidant properties of examined extract could be the mechanism of potential antiproliferative effect of extract.</p>

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