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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.
91

New 4-Aminoquinoline Compounds to Reverse Drug Resistance in <i>P. falciparum</i> Malaria, and a Survey of Early European Antimalarial Treatments

Liebman, Katherine May 11 December 2014 (has links)
Intermittent fevers caused by Plasmodium parasites have been known for millennia, and have caused untold human suffering. Today, millions of people are afflicted by malaria each year, and hundreds of thousands die. Historically, the most successful synthetic antimalarial drug was chloroquine, as it was safe, inexpensive, and highly efficacious. However, plasmodial resistance to chloroquine now greatly limits its utility. Previously in our laboratories it has been shown that attachment of a "reversal agent moiety" to the side chain of chloroquine can result in the restoration of activity against chloroquine-resistant strains of P. falciparum malaria. In the first part of the work presented here, a study has been made of the importance of the quinoline ring substitution pattern to the activity of such reversed chloroquines. The compounds presented here include those bearing a substituent in the 2-, 5, 6-, 7-, and/or 8- position, and include those with chloro, bromo, iodo, fluoro, nitro, trifluoromethyl, methyl, and methoxy substituents. For reversed chloroquines, 2-, 5-, and 8- substituents have been found to decrease in vitro antiplasmodial activity against P. falciparum relative to 7-chloro substitution, whereas 6- and 7- substituted compounds with various substituents have in many cases similar activity to that of 7-chloro substituted compounds. Little difference has been observed between 6- and 7- substitution, or between chlorine and a methyl group in position 6. In most cases these effects on activity are directionally similar to those observed for chloroquine analogs without an attached reversal agent, but the magnitude of the effect is generally smaller, suggesting that the activities of reversed chloroquines are less affected by modifications to the quinoline ring system than is true for chloroquine analogs without an attached reversal agent. The second portion of this work presents an asymmetrical bis-quinoline (PL241) that is highly active against P. falciparum malaria, with an IC50 of less than 0.1 nM for all strains tested. Mechanistic studies have been performed in which the substitution patterns of the two quinoline rings of PL241 are modified in ways that indicate that either ring system is equally capable of participating in the antimalarial activity of these compounds. The excellent in vitro antiplasmodial activity of PL241 makes this a compound of great interest for further development as a potential antimalarial drug. In the third part of this work, a survey has been made of antimalarial treatments recommended in the European medical literature from the time of Pliny the Elder (active in the first century A.D.) through the advent of modern malaria chemotherapy in the early twentieth century. In the fifteen primary sources utilized in this study, 251 distinct substances - primarily plants - were identified as having likely been used in the treatment of malaria. Of the 38 substances that were described in three or more sources, at least fifteen have been examined by other workers for antiplasmodial activity; in many cases, they were found to have antiplasmodial activity in vitro or in vivo. However, the majority of the phytotherapies for malaria identified in this project have not yet been tested against Plasmodium species, and may provide valuable leads in the search for new compounds active against drug-resistant malaria.
92

Le grenadier tunisien (Punica granatum) stimule le transport de glucose dans les cellules musculaires C2C12 via la voie insulino-dépendante de l’Akt et la voie insulino-indépendante de l’AMPK

Ben Abdennebi, Mohamed Amine 08 1900 (has links)
Le diabète est reconnu comme un problème majeur de santé publique causant des conséquences humaines et économiques redoutables. La phytothérapie s’offre comme une nouvelle avenue thérapeutique pour le contrôle de la glycémie. Le grenadier, Punica granatum, a servi de remède contre le diabète dans le système Unani de la médecine pratiquée en Inde et au Moyen Orient. Des études ont démontré un effet hypoglycémiant des extraits de grenadier via divers mécanismes notamment par une amélioration de la sensibilité à l’insuline et la régénération des cellules béta-pancréatiques. Cependant, aucune étude n’a démontré à ce jour, l’effet de grenadier sur le transport de glucose dans le muscle, étape cruciale dans la régulation de l’homéostasie glucidique postprandiale. De plus, l’effet de la maturation sur le potentiel antidiabétique du fruit de grenadier n’a pas été étudié. Ainsi, le but de ce projet est d’évaluer l’effet antidiabétique des extraits de grenadier sur le transport de glucose dans les cellules musculaires C2C12 en fonction de la variété et du stade de maturation du fruit et d’élucider les mécanismes d’action. Le choix des variétés du grenadier tunisien (Espagnoule [EP] et Gabsi [GB]) a été orienté pour leur pouvoir antioxydant et leur consommation locale. Deux parties de la plante ont été utilisées, les fleurs et les fruits à 3 stades de maturation soit 2, 4 et 6 mois. Les résultats ont montré que seule la variété du grenadier Gabsi stimule significativement le transport de glucose par rapport au contrôle (DMSO), et ceci sans être toxique. Cet effet est plus prononcé au stade de fruit mûr (à 6 mois) que celui de la fleur. De plus, l’extrait de fleurs stimule la voie insulino-indépendante de l’AMPK et augmente le niveau d’expression des transporteurs spécifiques de glucose (GLUT-4). Par contre, l’extrait de fruits mûrs, en plus de ces deux mécanismes, active fortement aussi la voie insulino-dépendante de l’AKT. En conclusion, cette étude présente un nouveau mécanisme d’action antidiabétique de grenadier (plus particulièrement du fruit mûr) qui est dépendant de la variété. / Diabetes is a major public health problem worldwide with astounding human and economic consequences. The seed and the flower of pomegranate (Punica granatum), a native plant of Central Asia and the Mediterranean regions, exhibited a hypoglycaemic effect in in vivo studies. However, the underlying mechanisms have not yet been elucidated. The aim of this project was to evaluate the effect of the flower and the fruit (at 3 maturation stages) of pomegranate on glucose transport in skeletal muscle cells and to determine the molecular mechanisms involved in this effect. To accomplish this, we chose two varieties of pomegranate cultivated in Tunisia (Gabsi [GB] and Espagnoule [EP]), which have been shown to be highly consumed in that area and to possess high antioxidant activity. Differentiated C2C12 cells were treated for 18 hours with 80% ethanolic extract of the flowers and fruits (at 2, 4, and 6 months) of each variety. Our results showed that the Gabsi variety of pomegranate significantly enhances glucose uptake, without any toxicity. This effect is more pronounced in the ripe fruit (6 months) than in the flower. In parallel, the ripe fruit stimulated both the insulin-dependent pathway (Akt) and the insulin-independent pathway (AMPK), while the flower stimulated the latter only. In addition, both flower and ripe fruit treatment resulted in enhanced expression level of GLUT-4 glucose transporter in the muscle. Hence, these results suggest that regulation of glucose transport in skeletal muscle is one of the components involved in the anti-diabetic effect of Tunisian pomegranate.
93

Četnost prodeje rostlinných přípravků v určitém regionu. Farmakobotanická a fytofarmakologická studie. / A frequency of a purchase of herbal medicines in selected regiones. Pharmacobotanical and phytopharmacological study.

Vyšinská, Ľubomíra January 2011 (has links)
VYŠINSKÁ, Ľ.: A frequency of a purchase of herbal medicine in selected regions. Pharmacobotanical and phytopharmacological study. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. Hradec Králové, 2011, 89 p. Keywords: phytopharmaceuticals, parapharmaceuticals, herbal drugs, phytomedicines, questionary survey Background: To examine the most frequently used herbal products in Žilina region and to identify factors associated with herbal therapy usage (age, gender of patients), as well as the situations when the phytopharmaceuticals are added to therapy (basic/add on therapy, therapeutical indications etc.). Thesis also tried to resolve the relationship of pharmacists and doctors to the herbal medicine and it dealt with the issue of information resources concerning phytotherapy, trends in this area and perception of the risks of the therapy among professionals. Methods: A questionnaire was used to find out the data. Respondents were pharmacist, always one person per pharmacy from a village in Žilina region. Results: Totally, 101 questionnaires were collected from 28 villages in Žilina region. From the evaluation of respondent's answers is clear that the most frequently sold phytopharmaceutical is a product from...
94

Les interventions thérapeutiques dans les pathologies inflammatoires et le cancer : compréhension des propriétés immunomodulatrices de Viscum album / Therapeutic intervention in inflammatory pathologies and cancer : understanding the anti-inflammatory properties of Viscum album

Hegde, Pushpa 26 June 2013 (has links)
Les progrès réalisés en immunologie ont orienté les recherches vers des approches et des stratégies de plus en plus prometteuses et innovantes afin de mieux manipuler la réponse immunitaire. Le but de nos recherches est la prévention et le traitement des maladies liées aux dysfonctionnements du système immunitaire, telles que les maladies auto-immunes, inflammatoires et malignes. Bien que l’inflammation constitue un processus physiologique indispensable au maintien de l’homéostasie suite à une infection ou à une lésion, elle est également associée à des pathologies infectieuses, auto-immunes et tumorales. Les stratégies thérapeutiques les plus utilisées pour traiter l’inflammation sont basées sur la neutralisation des médiateurs inflammatoires par des anticorps, des antagonistes moléculaires, des immunoglobulines intraveineuses, des corticostéroïdes, des médicaments anti-inflammatoires non stéroïdiens. En plus des traitements mentionnés, des produits issus de la phytothérapie ont été largement utilisés afin d’atténuer l'inflammation et la douleur dans plusieurs maladies inflammatoires et dans le cancer. Depuis des décennies, les préparations de Viscum album, connu sous le nom de « gui européen », sont largement utilisées dans le traitement du cancer comme thérapie auxiliaire. Bien que les mécanismes d’action soient partiellement connus, plusieurs hypothèses ont été proposées. En effet, les mécanismes anti-tumoraux du Viscum album impliquent des propriétés induisant une cytotoxicité, l'apoptose, l'inhibition de l'angiogenèse et plusieurs autres mécanismes immunomodulateurs. Ce travail décrit un nouveau mécanisme anti-inflammatoire de Viscum album, qui participe à l’effet thérapeutique de ces préparations. De plus, l’effet bénéfique anti-inflammatoire observé est associé à l’inhibition des voies pro- inflammatoires de COX2 et PGE2 dans les cellules épithéliales issues d’adénocarcinome du poumon. Ce travail a identifié un des mécanismes moléculaires de Viscum album associé à son effet anti-inflammatoire participant à ses bénéfices thérapeutiques. Ainsi, ces préparations pourraient être utilisées en combinaison avec d’autres traitements dans des maladies inflammatoires et dans le cancer. / Recent advances in immunology research have led us towards more promising approaches and strategies to manipulate the immune response to prevent or treat the diseases related to immune dysfunction such as autoimmune, inflammatory pathologies and malignant diseases. Although, immuno inflammation is a basal physiological phenomenon required to eliminate the causative agent and to initiate the healing process, it is a physiopathological symptom in a diverse conditions of infectious, autoimmune and tumoral origin. Various therapeutic strategies have been developed in order to reduce inflammation and pain, including the treatment with cytokine neutralizing antibodies, molecular antagonists, intravenous immunoglobulins, corticosteroids, non-steroid anti-inflammatory drugs (NSAID) and several others. In addition to these well known anti-inflammatory therapeutic strategies, treatment with various phytotherapeutics has also contributed enormously to control inflammation and pain, associated with various severe inflammatory disorders and cancer. Viscum album (VA) preparations, commonly known as European mistletoe, are extensively used as complementary therapy in cancer for decades. However the mechanisms of action have been partially understood. Several mutually non-exclusive mechanisms have been proposed such as anti-tumor properties which involve the cytotoxic properties, induction of apoptosis, inhibition of angiogenesis and several other immunomodulatory mechanisms. This study reveals anti-inflammatory mechanism as another important mechanism of action of these phytotherapeutics, which is responsible for their therapeutic benefit and addresses the molecular mechanisms in the pro-inflammatory axis of COX-2 and PGE2 using in vitro experimental model of human lung adenocarcinoma. The present work contributes for a better understanding of mechanisms of action of Viscum album preparations underlying their therapeutic benefit and allows us to revitalize the therapeutic strategies used in treatment of inflammatory disorders and cancer.
95

Análises celulares e moleculares das lignanas extraídas da Piper cubeba em linhagens tumorigênicas de cabeça e pescoço /

Gusson, Juliana Prado. January 2019 (has links)
Orientador: Flávia Cristina Rodrigues-Lisoni / Banca: Ana Paula Girol / Banca: Cristiéle da Silva Ribeiro / Resumo: O carcinoma espinocelular de cabeça e pescoço com acometimento de sítios anatômicos do trato aerodigestivo superior representa o sexto tipo mais comum de câncer no mundo. Algumas plantas vêm sendo utilizadas no tratamento do câncer e uma delas tem despertado interesse científico, a Piper cubeba. Com relação à importância da atividade antitumoral das lignanas extraídas da Piper cubeba, incluindo seus elementos químicos, foi proposto o presente trabalho que teve como objetivo geral avaliar o potencial efeito citotóxico e genotóxico de lignanas nas células sobre a morfologia, proliferação e migração celular, citotoxicidade, genotoxicidade, apoptose e necrose celular, e expressão gênica, observando como o fitoterápico age e como essas alterações participam do processo tumorigênico. Para isso foram utilizadas duas linhagens de células tumorigênicas e uma de células normais, após o tratamento com as lignanas cubebina, dihidrocubebina, etilcubebina, extrato total, hinoquinina e metilcubebina, todas extraídas das sementes de Piper cubeba em três concentrações (10 µg/mL, 50 µg/mL e 100 µg/mL), por 4, 24, 48 e 72 horas. A observação da morfologia foi realizada em microscópio invertido, o índice de proliferação pela curva de crescimento, a viabilidade celular foi determinada pelo método colorimétrico, MTS (CC50), migração celular pelo método de transwell, genotoxicidade pelo ensaio cometa, avaliação da apoptose por citômetro de fluxo e expressão gênica pela técnica de PCR quantitativo... / Abstract: Head and neck Squamous cell carcinoma with involvement of anatomical sites of the upper aerodigestive tract represents the sixth most common type of cancer in the world. Some plants have been used in the treatment of cancer and one of them has aroused scientific interest, Piper cubeba. Regarding the importance of the antitumor activity of the lignans extracted from Piper cubeba, including its chemical elements, the present work was proposed whose general objective was to evaluate the potential cytotoxic and genotoxic effects of lignans in cells on cell morphology, proliferation and migration, cytotoxicity, genotoxicity, apoptosis and cell necrosis and gene expression, observing how the phytotherapic acts and how these alterations participate in the tumorigenic process. After the treatment with the lignans cubebin, dihydrocubebin, ethylcubebin, total extract, hinokinin and metilcubebin, all of them were extracted from Piper cubeba seeds at three concentrations (10, 50 and 100μg/ml) for 4, 24, 48 and 72 hours. The morphology was determined by inverted microscopy, proliferation index by growth curve, cell viability was determined by the colorimetric method, MTS (IC50), cell migration by transwell method, genotoxicity by comet assay, flow cytometric apoptosis evaluation and gene expression by quantitative PCR technique. Statistical analysis was performed by analysis of variance for multiple comparisons (ANOVA), followed by Bonferroni adjustment by GraphPad Prism 5.0 software ... / Mestre
96

Prevenção de lesões de pele: Desenvolvimento de formulação tópica de micropartículas de quitosana com Chamomilla recutita (L.) rauschert e estudos preliminares de seu uso / Prevention of skin injuries: development of a topical formulation of chitosan microparticles with Chamomilla recutita (L.) Rauschert and preliminary studies of its use

Lui, Danielle Cristina Garbuio 09 November 2016 (has links)
As terapias integrativas e complementares têm sido utilizadas há tempos para o tratamento e prevenção de diversos males. A fitoterapia utiliza plantas para estes tratamentos e, dentre estas, destacamos a Chamomilla recutita (L.) rauschert, conhecida popularmente como camomila. Trata-se de uma planta muito utilizada popularmente com finalidades terapêuticas, que possui propriedades anti-inflamatórias, digestivas, calmantes e cicatrizantes. Frente a estas propriedades e em conjunto com a tecnologia farmacêutica para elaboração de micropartículas com liberação controlada, este estudo teve como objetivo desenvolver uma formulação tópica de micropartículas de quitosana com camomila e realizar estudos preliminares de seu uso considerando aplicações futuras para prevenção de lesões de pele. Para alcançar o objetivo proposto, este trabalho foi realizado em três partes. A primeira parte consistiu no desenvolvimento da formulação tópica a ser testada. Para isso, foi realizada a caracterização farmacognóstica do material vegetal adquirido, a extração da planta, a microencapsulação deste extrato e o teste com incorporação destas em diversas formulações. Nesta etapa, o material vegetal apresentou características recomendadas pela Farmacopeia Brasileira, o extrato e a microencapsulação apresentaram resultados positivos e ao final foram selecionadas três formulações para testes preliminares. Estes testes consistiram em um ensaio de permeação em célula de Franz e estudos de estabilidade preliminar, acelerada e de longa duração. Nestes testes das três formulações previamente escolhidas, apenas uma foi eleita para as demais etapas. Na segunda parte do estudo as micropartículas desenvolvidas foram testadas quanto à sua citotoxicidade em fibroblastos e queratinócitos de pele humana e também quanto ao seu efeito frente à exposição à radiação ionizante. Nestes ensaios as micropartículas demonstraram citotoxicidade apenas nas maiores concentrações. Observa-se que a toxicidade celular do extrato é maior quando comparado as microcápsulas. Ainda neste estudo, o maior efeito protetor para a radiação nas três soluções em teste foi observado na faixa de dose entre 1:1000000 e 1:10000 nos queratinócitos e entre as concentrações 1:1000000 e 1:10000 nos fibroblastos. Na última parte deste estudo foi desenvolvido um ensaio clínico fase I para verificar a segurança e eficácia preliminar da formulação em voluntários saudáveis. Participaram deste ensaio 35 voluntários que utilizaram a formulação teste em um antebraço e uma formulação sem as micropartículas para controle no outro antebraço durante 28 dias. De acordo com os resultados a formulação não causou eritema, descamação, ardor, prurido ou dor dentro de um período de quatro semanas de uso. Houve um aumento do conteúdo aquoso no local de aplicação da formulação com as micropartículas e no controle do mesmo braço. Na avaliação da função barreira houve um aumento da perda transepidérmica de água após o uso do produto, mas este aumento também foi encontrado nos controles. Conclui-se que a formulação é estável e segura para o uso na pele íntegra e seus efeitos na hidratação da pele e na função barreira devem ser melhor estudados / Integrative and complementary therapies have long been used in treatment and prevention of diverse problems. Phytotherapy uses plants for these treatments and, among these, we highlight the Chamomilla recutita (L.) Rauschert, popularly known as chamomile. This is a very commonly plant, which is used for therapeutic purposes and has anti-inflammatory, digestive, soothing and healing properties. Considering these properties and the pharmaceutical technology for preparation of microparticles, this study aimed to develop a topical formulation with chitosan-chamomile microparticles and conduct preliminary studies of their use, taking into account future applications for the prevention of skin lesions. To achieve the proposed objective, this study was performed in three parts. The first part was the development of topical formulation to be tested. To do so, a number of actions were carried out, namely pharmacognostic characterization of plant material, the extraction of the plant, the microencapsulation of the test extract and its incorporation in various formulations. In this step, the plant material showed characteristics recommended by the Brazilian Pharmacopeia: the extract microencapsulation showed positive results and three final formulations were selected for preliminary testing. These tests consisted of a permeation test using Franz cell; and preliminary, short-time and long-time stability studies. In these tests, only one of these three formulations was selected for the remaining steps. In the second part of the study, the microparticles were tested for both their cytotoxicity in fibroblasts and keratinocytes from human skin, and for the effect of being exposed to ionizing radiation. These tests revealed cytotoxicity only at higher concentrations. The cellular toxicity of the extract is higher when compared to the microcapsules. The best protective effect of tested formulations varies between 1:1000000 and 1:10000 in keratinocytes and between 1:1000000 and 1:10000 in fibroblasts. In the last part of this study, a clinical trial phase I was conducted to check the safety and preliminary efficacy of the formulation in healthy volunteers. Thirty-five volunteers participated by using the formulation in test on a forearm, and a formulation without the microparticles to control on the the other forearm for 28 days. According to results, the formulation did not cause erythema, peeling, burning, itching or pain within the aforementioned period. There was an improvement in aqueous content of stratum corneum in the application site with the microparticles and in the control of the same arm. When assessing the barrier function, there was an increase in transepidermal water loss after using the product, but this increase was also found in the controls. We concluded that the formulation is stable and safe for use in healthy skin, and its effects on skin hydration and barrier function should be better studied
97

Développement d’outils moléculaires et cellulaires pour générer des variétés de Pomelo « Star Ruby » ne produisant pas de Furocoumarines / Development of molecular and cellular tools to generate Star Ruby grapefruit varieties non producing furanocoumarins

Limones Méndez, Mariana Cecilia 04 June 2019 (has links)
Les furocoumarines sont des composés phénoliques impliqués dans la défense contre les herbivores. Ces molécules sont majoritairement décrites dans quatre familles botaniques, notamment les Rutaceae, dont font partie les agrumes. Ces molécules sont phototoxiques ce qui peut poser des problèmes pour leur utilisation comme par exemple en cosmétique ou en phytothérapie. D’autre part, en cas d’ingestion par exemple via la consommation de jus de certains agrumes, elles ont responsables de l’inhibition d’enzymes de détoxication comme le CYP3A4 humain. Cela peut conduire à des surdosages médicamenteux connus sous le nom d’Effet Pomelo. Ce travail de thèse a consisté à réfléchir et à développer, des outils qui permettront de générer de manière ciblée des variétés de pomelo qui ne produisent plus de furocoumarines. Nous avons abordé l’ensemble des étapes essentielles pour la mise en place d’une stratégie global : i) des méthodes reproductibles ont été développées pour la production de protoplastes et de cultures cellulaires de pomelo Star Ruby ; ii) des conditions de transformation de protoplastes par électroporation ont également été mises au point ; iii) finalement, pour inhiber de manière spécifique la voie de biosynthèse des furocoumarines, nous avons choisi de mettre en œuvre une approche d’édition de génome en utilisant une méthodologie CRISPR/Cas9. La mise au point de la méthode a été réalisée avec un gène codant pour une umbelliferone 6-dimethylallyl transférase. Les résultats obtenus indiquent que la stratégie est envisageable. Pour renforcer la stratégie CRISPR/Cas9, nous avons mis en œuvre une démarche d’identification de gènes cibles additionnels. En utilisant une approche de data mining de bases de données génomiques et transcriptomiques nous avons identifié 18 séquences candidates, potentiellement impliquées dans la voie de biosynthèse des furocoumarines. L’expression hétérologue des protéines correspondantes et leur caractérisation fonctionnelle a permis de montrer que CYP706J12 est en mesure de métaboliser l’hérniarine, une coumarine. Ce résultat apporte des éléments pour émettre des hypothèses sur l’évolution convergente de la synthèse des coumarines et des furocoumarines chez les végétaux supérieurs. / Furanocoumarins are phenolic compounds involved in defense against herbivores. These molecules are mainly described in four botanical families. Rutaceae, one of those families, includes Citrus species. Furanocoumarins are phototoxic compounds, which can be problematic for their use in cosmetics or in phytotherapy. Furanocoumarin ingestion via citrus juice consumption, may inhibit human enzymes of detoxification, such as human CYP3A4. This can lead to drug overdoses known as the “Grapefruit Juice Effect”. This work consisted in the development of tools that will allow to generate new varieties of pomelo that no longer produce furanocoumarins by targeted genome edition. We have covered the essential steps for the implementation of a global strategy: i) reproducible methods have been developed for the production of protoplasts and cell cultures of Star Ruby grapefruit; ii) conditions for protoplast transformation by electroporation have also been developed; iii) finally, to specifically inhibit the furanocoumarin biosynthetic pathway, we chose to implement a genome editing approach using a CRISPR / Cas9 methodology. The development of the method was carried out with a gene encoding umbelliferon 6-dimethylallyltransferase. The results obtained indicate that the strategy is feasible. To strengthen the CRISPR / Cas9 strategy, we implemented a method to identify additional target genes. Using a data mining approach of available genomic and transcriptomic databases we identified 18 candidate sequences potentially involved in the furanocoumarin biosynthetic pathway. Heterologous expression of the corresponding proteins and their functional characterization made it possible to show that CYP706J12 is able to metabolize herniarin (a coumarin). This result provides elements to hypothesize about the convergent evolution of coumarin and furanocoumarin synthesis in higher plants.
98

Bioverfügbarkeit und Metabolismus von Flavonoiden / Bioavailability and metabolism of flavonoids

Wittig, Jörg January 2001 (has links) (PDF)
Ziel der vorliegenden Arbeit war die Entwicklung, Optimierung und Validierung von phyto- und bioanalytischen Analysemethoden. Dabei wurden exemplarische Fragestellungen aus dem Themenkreis Phytotherapie bzw. Bioverfügbarkeit und Metabolismus von einfachen und Polyphenolen bearbeitet. Quercetin und seine Derivate: Zur qualitativen Analyse der Flavonoide und -derivate in einem Trockenextraktgemisch aus Birkenblättern, Goldrutenkraut und Orthosiphonblättern wurde eine HPLC- UV/VIS Methode entwickelt. Nach oraler Applikation dieses Trockenextraktgemisches als orale Arzneiform wurde die systemische Verfügbarkeit von Quercetin bzw. Quercetinglykosiden untersucht, welche für Quercetin bzw. -glykosiden 0 Prozent betrug (LOD ~ 25 pg Quercetin on column), da Quercetin als Phase-I- bzw. -II- Metabolite vorlag. Nach Hydrolyse der Phase-II-Konjugate wurden die höchsten Quercetinspiegel (101±107 ng·mL-1) nach ca. 4 Stunden (tmax) gemessen. Der Zeitpunkt der höchsten renalen Quercetinausscheidung lag im Intervall von 4?8 Stunden nach Verum-Gabe, wobei die über 24 Stunden ausgeschiedene Quercetinmenge 604±1037 µg·mL-1 betrug. Im Rahmen der studienbegleitenden bioanalytischen Methodenentwicklung wurde eine Extraktionsmethode für Plasma und Urin entwickelt und validiert. Durch Anwendung eines neuartigen Analyseverfahrens, der coulometrischen Array-Detektion, konnte eine HPLC-Methode entwickelt werden, die erstmals Quercetin und seine Metabolite simultan, selektiv und ausreichend sensitiv in biologischen Matrices detektieren konnte. Unter Verwendung des analytischen Verfahrens der HPLC-Tandemmassenspektrometrie konnten erstmals fünf Quercetinglucuronide als die Hauptmetabolite des Quercetins identifiziert werden. Um weitere Erkenntnisse über den Metabolismus der systemisch verfügbaren Quercetinglucuronide am Venenendothelgewebe zu gewinnen, wurde ein In-vitro-Modell unter Verwendung von HUVEC (human umbilical endothelial cells)- Monolayerkulturen entwickelt und orientierend validiert. Die Experimente zeigten, dass das Venenendothel Glucuronidaseaktivität aufweist und somit Quercetin in-situ am oder im Zielgewebe aus systemisch vorliegenden Glucuroniden freisetzen kann. Die frei vorliegenden Aglykone können dann in das Venenendothelgewebe aufgenommen werden. Das In-vitro-Modell gibt damit erstmals einen plausiblen Erklärungsansatz für die Wirksamkeit von Quercetinderivat-haltigen Präparaten in-vivo, z.B. beim varikösen Symptomen-Komplex. Procyanidine in Weißdorn: Zur Gruppenbestimmung der Procyanide in Weißdornpräparaten wurde ein Analysenprotokoll optimiert und validiert, welches den derzeit üblichen Protokollen bezüglich des Grades an Selektivität überlegen ist. Weiterführend wurde zur selektiven Analyse der mono- bis trimeren Procyanidine in Weißdornpräparaten eine HPLC-Methode unter Adaption eines Nachsäulenderivatisierungsverfahrens (NSD) entwickelt und validiert. Unter Kombination beider Verfahren konnte erstmals das Procyanidinspektrum in handelsüblichen Weißdornpräparaten durch Einbeziehung der mono- bis trimeren Procyanidine, näher beschrieben, und marktführende Weißdornpräparate vergleichend analysiert werden. In Zusammenhang mit publizierten pharmakologischen Arbeiten mit teilweise identischen Extrakten, leisten die in dieser Arbeit erlangten Kenntnisse über Gehalt und Polymerisationsgrad der in den untersuchten Phytopharmaka enthaltenen Procyanidine einen Beitrag zum besseren Verständnis der Wirkungen von Weißdorn-Zubereitungen insgesamt. Hydrochinon und seine Derivate: Die renale Verfügbarkeit von Hydrochinon nach oraler Gabe einer flüssigen und einer festen Bärentraubenblätterextrakt-Zubereitung wurde anhand einer Probandenstudie gezeigt. Das mit dem Bärentraubenblätter-Trockenextrakt applizierte Arbutin (210 mg, &#8776; 771,3 µmol) wurde zu ca. 0,18 Prozent als freies Hydrochinon (&#8776; 1,38 ± 0,79 µmol) ausgeschieden. Der Zeitpunkt der maximalen Hydrochinon-Ausscheidung (0,3±0,1 µg) lag bei beiden Arzneiformen im 4-8 Stunden-Intervall nach Applikation. Zur Analyse des Hydrochinons bzw. seiner Konjugate in humanem Urin wurde eine Extraktionsmethode zur simultanen Extraktion entwickelt und für den Zielanalyten Hydrochinon validiert. Durch Anwendung der coulometrischen Array-Detektion, konnten in Probandenurin erstmals Substanz-Zeit-Kinetiken freien Hydrochinons detektiert werden. Die in der vorliegenden Arbeit erhobenen In-vivo-Daten erlauben damit eine Korrelation von einerseits In-vitro-Daten zur bakteriziden Aktivität von Hydrochinon und andererseits epidemiologischen Daten zur Wirksamkeit von Bärentraubenblätter-Zubereitungen. Damit konnte erstmals unter therapiekonformen Bedingungen das für Bärentraubenblätter postulierte Wirkprinzip - das Hydrochinon - in-vivo bestätigt werden. / The aim of the investigations presented here was the development, optimisation, and validation of procedures and methods for the analysis of biological and plant samples. It focused on exemplary questions in the main topics “phytotherapy” and “bioavailability and metabolism of phenols and polyphenols”. Quercetin and its derivatives: In order to analyse the components of a mixture of dry extracts from birch leaves, solidago herb, and orthosiphon leaves qualitatively, a HPLC-method with UV/VIS-detection was developed. After oral administration of a solid drug preparation containing dry extracts of birch leaves (1.31 g), solidago herb (1.63 g), and orthosiphon leaves (1.61 g) the systemic availability was investigated. The outcome of the study showed a systemic availability of quercetin and quercetin glucoside of zero per cent (LOD ~ 25 pg quercetin on column) and revealed phase-II-conjugates of quercetin as the main systemic metabolites. After the hydrolysis of these quercetin conjugates the highest quercetin levels (cmax = 101±107 ng·mL-1) in human plasma were determined four hours after medication intake. Maximum renal elimination of quercetin conjugates was determined within the four to eight hours interval, and after 24 hours about 604 ± 1037 µg quercetin was eliminated. In order to make both phase-I and phase-II metabolites of quercetin accessible for HPLC analysis, a method for simultaneous extraction from human plasma and urine was developed. By employing a new coulometric array detection method an HPLC-method could be developed, which achieved the selective and sufficiently sensitive detection of quercetin and its metabolites in human body fluids for the first time. Furthermore five quercetin glucuronides could be detected in human plasma by the means of tandem mass spectrometry as the main systemic metabolites of quercetin in men. No quercetin glucosides could be detected in human plasma (LOD = 200 pg on column), which finally finished a controversial discussion about the bioavailability of quercetin glucosides. To increase the knowledge of the metabolism of the systemically available quercetin glucuronides, an in-vitro assay was developed and basically validated by using monolayers from human umbilical vein endothelial cells (HUVEC) as a model tissue. In the experiments the HUVEC tissue showed glucuronidase activity. Quercetin glucuronides were deconjugated in-situ resulting in the free aglycone which was taken up by the endothelial cells. This metabolism step represents the "missing link" between systemic available conjugated quercetin and the more antioxidant active aglycone. Procyanidines in Hawthorn: For analysis of total procyanidines occurring in Hawthorn flowers and leaves a determination procedure was developed and validated which, is superior to other protocols by its degree of selectivity. Furthermore a HPLC method employing post column derivatisation (PCD) and VIS detection was developed and validated for the selective determination of monomere, dimere, and trimere procyanidines in Hawthorn. Both methods, the procedure for the determination of total procyanidines and the HPLC-PCD method for determination of mono-, di-, and trimere procyanidines were applied to the analysis of herbal medicinal products (HMP) containing hawthorn extracts. This enables to have a closer look on content and polymerisation degree of the procyanidins occurring in leading Hawthorn HMPs of the German market and is a considerable step forward to guarantee the pharmaceutical quality. Taken together with the pharmacological data published for HMP the knowledge of content and polymerisation degree of procyanidines contributes to a better understanding of the efficacy of Hawthorn containing preparations. Hydroquinone and its derivatives: For the analysis of hydroquinone in human urine a method for simultaneous extraction of hydroquinone and its conjugates was developed and validated. The renal availability of hydroquinone was established in a clinical study by application of a solid and a liquid HMP containing a dry extract of bearberry leaves to healthy volunteers. By using the coulometric array detection, selective and sufficiently sensitive determination of hydroquinone in human urine by HPLC was achieved and the collection of sufficient pharmacokinetic data was possible for the first time. About 0.18 per cent (&#8776; 1,38 ± 0,79 µmol) of the orally given hydroquinone glucoside (arbutin, 210 mg, &#8776; 771,3 µmol) was excreted as free hydroquinone renally. The maximum renal hydroquinone excretion (0,3 ± 0,1 µg) lied within the 4-8 hours interval after application of both the solid and the liquid HMP. These results confirm the active principle hydroquinone postulated for bearberry leaves in-vivo under therapeutic conditions for the first time.
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Phytopharmaka und Pharmazeutika in Heinrich von Pfalzpaints "Wündärznei" (1460) / Phytopharmaka and Pharmaceutics in Heinrich von Pfalzpaints Wündärznei (1460)

Richter, Claudia January 2003 (has links) (PDF)
Bis heute wurden acht Handschriften der Wundarznei des Heinrich von Pfalzpaint entdeckt. Nach einer Revision der „Breslauer Handschrift“ wurde am Medizinhistorischen Institut der Universität Würzburg bereits mit einer textkritischen Gesamtedition aller bisher bekannten Pfalzpaint-Texte begonnen. Was nun die Konzeption und die Makrostruktur der vorliegenden Studie angeht, hat sich die Grobgliederung in einen allgemeinen Teil, einen Kommentar zur ‚Wündärznei‘ und einen pflanzenmonographischen Abschnitt bewährt. Somit kann sowohl über den Pfalzpaintschen Text ein schneller Zugriff auf den alphabetisch geordneten Pflanzenteil erfolgen. Aber auch der umgekehrte Weg ist möglich, da in den einzelnen Monographien stets sämtliche Synonymnamen sowie die Indikationsbereiche mit genauer Kapitelnummer angegeben wurden. Durch Erstellen eines Kommentars konnten zunächst zahlreiche wundärztliche Begriffe geklärt und der Textinhalt in eine heute verständliche Sprache gebracht werden. Dabei muß festgehalten werden, daß die am Ende der ‚Wündärznei‘ positionierten Pestrezepte mit großer Wahrscheinlichkeit nicht von Pfalzpaint stammen, sondern zu einem späteren Zeitpunkt angehängt wurden. Textaufbau, Schreibstil, verwendete Fachtermini und das Fehlen in Pfalzpaints Register sprechen für diese Annahme. In der vorliegenden Studie wurden alle arzneilich verwendeten Pflanzen registriert, auch wenn es nicht möglich war, jede mit absoluter Sicherheit zu identifizieren. Hier hat sich das bereits in der Einleitung erwähnte Differenzierungsschema bewährt. Es ermöglicht, daß man schon bei Betrachtung der Pflanzenkapitel anhand der Identifikationsklassen I-V sofort erkennen kann, ob es sich um eine eindeutig identifizierte Pflanze handelt. Bei unsicherer Zuordnung erfolgt in der Monographie jeweils eine argumentative Abwägung der konkurrierenden Identifikationsmöglichkeiten. Nun möchte ich, um hinsichtlich der Identifizierung der Statistik zu genügen, noch einige Prozentangaben bereitstellen: Bei der Auswertung der fünf erwähnten Identifikationsklassen konnte festgestellt werden, daß fast zwei Drittel der verwendeten Pflanzen (65%) bereits über den Namen zu identifizieren waren. Durch Pfalzpaints Nennung von Synonymen, botanischen Beschreibungen und Indikationen wurde es weiterhin möglich, weitere 18% sicher zuzuordnen. In 25 Fällen (15%) konkurrierten mehrere Lösungsansätze, und es mußte eine eindeutige Identifizierung unterbleiben. Von den 171 bearbeiteten Pflanzen sind heute noch 20% (34 Drogen) offizinell im Europäischen Arzneibuch, Nachtrag 2001, verzeichnet; hier seien beispielhaft die Enzianwurzel, der Tormentillwurzelstock, die Gewürznelken und die Salbeiblätter genannt. Beim Vergleich mit dem „Leitfaden Phytotherapie“ von Schilcher/Kammerer fällt auf, daß etwa 40% des Pfalzpaint-Repertoires heute noch verwendet werden und daß weitere 17% zwar erwähnt, aber mit einer Negativmonographie belegt sind. Bei etwa 15% der Arzneipflanzen handelt es sich um importierte Drogen (z.B. Mastix, Zitwer, Ingwer), die stets eindeutig identifiziert werden konnten. In diesem Zusammenhang vermute ich - gestützt auf das ‚Circa instans‘ -, daß durch den Import und die damit verbundenen Handelsgeschäfte die Identifizierung bereits beim Kauf erfolgte (auch wenn es sich möglicherweise um Fälschungen wie z.B. beim Safran handeln konnte). Was machte die Bearbeitung der ‚Wündarznei‘ des Heinrich von Pfalzpaint so interessant und einmalig? Zum einen enthält der Text einen überraschenden Reichtum an wundchirurgischen Arbeitsweisen - angefangen mit der Versorgung einer einfachen Schnittwunde bis hin zu progressiven operativen Verfahren: ich erinnere an die Nasenersatzplastik, an die Hasenschartenoperation oder an das Vorgehen bei Darmoperationen. Bei der Nasenersatzplastik handelt es sich um eine Erstbeschreibung eines hochkomplexen Verfahrens, was erkennen läßt, daß Pfalzpaint ein Meister im Umgang mit der Sprache ist und erstmals solch schwierige Techniken zu erklären vermag. Auch auf dem Gebiet der Arzneistoffkenntnis und der galenischen Herstellungstechnik von Salben, Pflastern und anderen Arzneiformen kennt sich Pfalzpaint sehr gut aus. Auch durch die politische Situation bedingt, nämlich durch die Belagerung der Marienburg, erhält man Einblick in die medizinische und arzneiliche Versorgung von Kranken in Notzeiten. Alle diese Aspekt machen die ‚Wündärznei‘ Heinrich von Pfalzpaints zu einem wichtigen Dokument des medizinischen Systems des Spätmittelalters. / Today we know of eight manuscripts of ‚Heinrich von Pfalzpaint‘. Let’s now turn to the concept and macrostructure of the study at hand. The following method proved to be most rewarding: a division into a general part, a comment on ‚Wündärznei‘ and a section on botanical monographs. Hence, the Pfalzpaint text provides quick access to the alphabetically arranged section on plants. Nevertheless, the reverse method is also possible because the single monographs specify all synonyms and the indication fields with the exact chapter numbers. In creating a commentary one could identify numerous terms in the area of medicinal wound treatment and translate their respective meanings into an easily comprehensible present-day language. While doing so, it has to be kept in mind, however, that in all probability the prescriptions on plague treatment situated at the end of the ‚Wündärznei‘ do not go back to Pfalzpaint. They were added at a later time. Text structure, writing style, used terminology and the lack of a Pfalzpaint index support this presumption. The study at hand registers all medicinally used plants although it was not possible to classify all of them with absolute certainty. The system of differentiation mentioned in the introduction, proved to be very useful in that regard. Consequently, using the categories of identification no. I-V for a closer inspection of the chapters on plants, one is able to find out immediately if the respective plant is clearly identifiable or not. In case of uncertain classification, the monograph uses an argumentative approach to deal with the various competing possibilities of identification. I would like to meet the requirements of statistical identification methods and provide some proportional data. The examination of the five given possibilities of identification revealed that almost two thirds of the used plants (65 %) could be identified by their names. In addition, Pfalzpaint‘s naming of synonyms, botanical descriptions and indications made it possible to clearly categorize an additional 18 % of the plants. In 25 cases (15 %), however, several suggested solutions compete with each other which makes an absolute classification impossible. 20 % (34 drugs) of the 171 plants dealt with in this study are still listed in the European drugs register (supplement 2001); for example „Gentianae radix“, „Tormentillae rhizoma“, „Caryophylli flos“ and „Salviae folium“. A comparison with the „Phytotherapy Guide“ reveals, that about 40 % of the Pfalzpaint repertoire is still used today. In addition, about 17 % are mentioned there; however, they are listed with a negative monograph. About 15 % of the medicinal plants are imported drugs and therefore clearly identifiable (e.g. „Mastix resina“, „Zedoaria rhizoma“, „Zingiberis rhizoma“). Using the „Circa Instans“ as basis for my argument, I suppose that in cases of import and respective trade business the identification of medicinal plants happened at the time of purchase (although fake identification was likely to take place here as well, as in the case of saffron). Now, why is it that work on the ‚Heinrich von Pfalzpaint’s‘ ‚Wündärznei‘ appears to be that interesting and unique? On the one hand, this document lists an astonishing variety of methods in the area of wound surgery: from the treatment of ordinary cuts to progressive surgery methods. Let’s just recall the nose spare part surgery, the hare lip surgery, or the intestinal surgery in that regard. The nose spare part surgery, for example, is considered to be the first description of a very complex scientific method. It shows Pfalzpaint’s excellency in handling the language and his ability to explain such highly difficult techniques. Pfalzpaint is also very well-informed in the area of drug knowledge and familiar with the Galenic method of producing ointments, plasters and other types of medicine. Besides, the political situation of the time, namely the siege of the fortress Marienburg, provides further insight into the medical and medicinal treatment of ill people in times of need. All these fore-mentioned aspects illustrate why the ‚Heinrich von Pfalzpaint’s‘ ‚Wündärznei‘ is such an important document of the medical system in the Late Medieval Age.
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Evaluation of the combined use of saw palmetto and alfuzosin in the treatment of benign prostatic hyperplasia / 鋸櫚草與alfuzosin併用治療良性前列腺肥大之探討

Shu-chen Chang, 張素真 January 2006 (has links)
碩士 / 南華大學 / 自然醫學研究所 / 95 / This study aims to investigate the clinical effects of a phytotherapeutic agent saw palmetto, the drug Alfuzosin, both singly and jointly in patients experiencing lower urinary tract symptoms (LUTS) who were also diagnosed with benign prostatic hyperplasia (BPH). A total of 28 patients diagnosed with BPH and met the study criteria were divided into three groups based on the severity of their symptoms. Those of mild severity (n=10) were asked to take saw palmetto extract at 320mg per day (Group P) and those of moderate severity (n=10) were asked to take alfuzosin at 10 mg per day (Group A). Those of greatest severity (n=8) were asked to take both saw palmetto extract and alfuzosin (Group PA). Serum prostate specific antigen (PSA), maximal flow rate (Qmax), prostate volume (PV), and the International Prostate Symptom Score (IPSS) were obtained at the baseline and at the end of the three-month intervention. Results indicated that PV decreased by 4.8±8.2cc and 3.8±1.8cc in the Group P and Group PA and the reduction was significantly lowered than that in the Group A (p=0.032).     In the IPSS score, the reduction in Group PA (-7.6±3.0) and Group A (-4.3±1.3) were significantly greater than that of Group P (-3.1±3.0) (p=0.003). The reduction in score was attributed by the changes in the obstructive symptoms (p=0.005) and three of its four items, namely, incomplete emptying (p=0.029), intermittency (p=0.032), and weak stream (p=0.018). The reduction in Group P was not significantly differed from that of Group A and that Group PA was not significantly differed from that of Group A. In conclusion, this study found that saw palmetto extract can improve certain lower urinary tract symptoms, particularly those of obstruction in nature, associated with BPH.     The combined effect of saw palmetto and alfuzosin appeared to be more significant than when these agents were used singly. Future clinical studies in this area may provide patients with BPH additional therapeutical choices.

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