255 resultados para aboriginal traditional medicine

em Université de Lausanne, Switzerland


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Les plantes médicinales représentent la seule source de médicaments pour près de 90 % de la population de certains pays d?Afrique. Le savoir-faire des guérisseurs traditionnels, d?une valeur inestimable, représente un point de départ pour l?investigation pharmacologique et phytochimique de ces médicaments naturels. Dans le cadre de ce travail, nous nous sommes dans un premier temps intéressés à valider l?utilisation en médecine traditionnelle de deux plantes, Diuscorea sylvatica (Dioscoreaceae) et Urginea altissima (Liliaceae), qui produisent, lorsqu?elles sont frottées sur la peau, une inflammation et des démangeaisons. Ces réactions cutanées ont pu être expliquées, au moins en partie, par la présence d?aiguilles acérées d?oxalate de calcium dans les organes souterrains. Ces microtraumatismes répétés de l?épiderme risquent de provoquer, lors d?une utilisation prolongée, des lésions granulomateuses. L?histamine n?a pas été détectée, mais d?autres substances pourraient être impliquées dans le processus inflammatoire. La seconde partie de ce travail a consisté en la détection, l?isolement et la caractérisation de nouveaux composés naturels présentant un intérêt thérapeutique potentiel. 70 extraits provenant de 28 plantes supérieures du Zimbabwe ont été soumis à un criblage chimique et biologique. Les extraits méthanoliques des parties aériennes de Jamesbrittenia fodina et J. elegantissima (Scrophulariaceae) ont été sélectionnés sur la base de leurs nombreuses activités. Le fractionnement guidé par l?activité de J. fudina a permis l?isolement des saponines A et B, responsables des activités antifongique, antibactérienne et molluscicide de l?extrait. De plus, les deux saponines ont montré une activité équivalente en tant qu?inhibiteurs de l?acétylcholinestérase, propriété encore non décrite pour cette classe de composés. Une analyse LC/uv/MS de l?extrait a permis d?attribuer l?activité antiradicalaire au verbascoside, un dérivé du phenylpropane; cette analyse a de plus montré la présence d?une série de dérivés de l?acide cinnamique, dont l?isolement a été entrepris. Deux problèmes d?instabilité sont apparus, empêchant l?isolement des composés par des méthodes chromatographiques de pointe, en dépit de très bonnes conditions de séparations. Des analyses LC/?H-NMR combinées à des analyses RMN classiques des mélanges ont permis d?attribuer ces instabilités d?une part à une isomérisation cis/trans induite par la lumière, et d?autre part à une transacylation du groupe cinnamoyl sur une unité de sucre. Ceci a permis l?identification de 12 esters cinnamiques d?iridoïdes, dont 8 nouveaux produits naturels. Ces dérivés présentent un intérêt thérapeutique, car des composés similaires ont montré des propriétés anti-inflammatoires significatives dans différents modèles in vivo. Deux flavanones ont aussi été isolées de l?extrait. Cette classe de composés n?a jamais été rapportée chez un membre des Scrophulariaceae. Une analyse LC/UV/MS comparative des extraits polaires des deux espèces, J. fodina et J. elegantissima, a été effectuée pour détecter la présence éventuelle de compos.és communs. Les saponines A et B et le verbascoside ont été identifiés dans l?extrait de J. elegantissima. Trois flavonoïdes ont de plus été isolés de ce dernier par CPC et HPLC semi-préparative.<br/><br/>In certain African countries, medicinal plants represent the unique source of to 90% of the population. The knowledge of traditional healers represents a basis for the pharmacological and phytochemical investigation of these natural medicines. This work first focused on the validation of use of two plants frequently employed in traditional medicine, Dioscorea sylvatica (Dioscoreaceae) and Urginea altissimu (Liliaceae), which produce mild inflammation and itching when rubbed on the skin. These cutaneous reactions were shown to be due, at least in part, to the presence of sharp needles of calcium oxalate, implying the risk of granulomatous lesions following a long term use. Histamine was not detected, but other compounds could be involved in the inflammatory process. The second part of this work consisted of the detection, isolation and characterisation of new natural compounds of potential therapeutic interest from African plants. Seventy extracts obtained from 28 higher plants of Zimbabwe were submitted to a chemical and biological screening. The methanol extracts of the whole plants of Jamesbrittenia fodina and J. elegantissima (Scrophulariaceae) were selected for their various activities. An activity-guided fractionation of J. fodina led to the isolation of the saponins A and B, responsible for the antifungal, antibacterial and molluscicidal properties. Both saponins were equally active as inhibitors of acetylcholinesterase, a property that has, to our knowledge, never been described for this class of compounds. A LC/UV/MS analysis of the extract allowed the identification of verbascoside as the product with radical scavenging activity, and indicated the presence of a series of potentially interesting cinnamic acid derivatives. Two types of instability problems occurred in the course of their isolation, as some compounds could not be separated despite very good chromatographic conditions. LC/'H-NMR analyses combined with in-mixture NMR analyses enabled the attribution of the cause of the instability in one case to a cidtrans light-induced isomerisation, and in the other case to a transacylation of the cinnamoyl moiety on a sugar residue. These problems of instability have not been the object of previous studies. 12 cinnamic iridoid esters could be characterised, 8 of these being new natural compounds. Several similar substances have displayed significant anti-inflammatory properties in different in vivo models, suggesting a therapeutic interest for these new derivatives. Two flavanones were isolated from the same extract. This class of compound has not been previously reported from species of the Scrophulariaceae family. A comparative LCAJVNS study of the polar extracts of the two species J. elegantissima and J. fodina was performed in order to detect possible common compounds. Saponins A and B and verbascoside were thus identified in .J. elegantissima. Moreover, three supplementary flavonoids were isolated from J. elegantissima..

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ETHNOPHARMACOLOGICAL RELEVANCE: "Reverse pharmacology", also called "bedside-to-bench" or "field to pharmacy" approach, is a research process starting with documentation of clinical outcome as observed by patients with different therapeutic regimens. The treatment most significantly associated with cure is selected for future studies: first, clinical safety and efficacy; then in vivo and vitro studies. Some clinical data, i.e. details on patient status and progress, can be collected during ethnobotanical surveys; they will help clinical researchers and, once effectiveness and safety are established, will also help users of traditional medicine make safer and more effective choices. To gather clinical data successfully, ethnopharmacologists need to be backed by an appropriate team of specialists in medicine and epidemiology. Ethnopharmacologists can also gather important data on traditional medicine safety. MATERIALS AND METHODS: The first step is to create a consensus on the meaning of "clinical data", their interest and importance. An understanding of why "a cure is not a proof of effectiveness" is a starting point to avoid faulty interpretation of the clinical observations. RESULTS: Experience showed that, with the "bedside-to-bench" approach, a treatment derived from traditional recipe can be scientifically validated (in terms of safety and effectiveness) with a cost of less than a million euros, thus providing an end-product that is affordable, available and sustainable. CONCLUSIONS: With rigorous clinical study results, medicinal plant users gain the possibility to refine heath strategies. The field surveyor may gain a better relationship with the population, once she/he is seen as bringing information useful for the quality of care in the community.

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Résumé A Madagascar, comme dans plusieurs pays en développement, une grande partie de la population utilise les plantes pour se soigner. Plusieurs espèces des plantes sont ainsi utilisées en médecine traditionnelle malgache. Par ailleurs, la plupart de ces plantes ne font l'objet que de très peu d'étude scientifique. En effet, dans le cadre de l'investigation phytochimique de plantes utilisées en médecine traditionnelle malgache et dans la recherche des nouvelles substances biologiquement actives, Hypoestes serpens (Vahl) R. Br. (Acanthaceae) a été étudiée. Elle se présente sous deux variétés (glabre et poilue) qui sont tous utilisées dans la région sud-centre de Madagascar pour traiter la blennorragie. De l'extrait dichlorométhanique des feuilles de H. serpens (Vahl) R. Br. variété glabre, 12 diterpénoides dont 8 nouveaux ont été isolés. Ils ont tous montré une activité antifongique contre un champignon pathogène des plantes, Cladosporium cucumerinum, dans la bioautographie directe sur CCM. Quelques-uns ont également présenté une activité contre une levure saprophyte chez l'homme, Candida albicans et une activité inhibitrice de l'enzyme acétylcholinesterase. Les diterpènoïdes sont déjà considérés comme les principaux métabolites secondaires du genre Hypoestes. Le fractionnement de l'extrait méthanolique a conduit à l'isolement de 5 glycosides des flavonoïdes dont 4 sous formes C-g,lycosides qui n'ont jamais été identifiés dans la famille Acanthaceae. Ces flavonoïdes ont présenté une activité antiradicalaire contre le DPPH. Le fractionnement et la purification des extraits ont été effectués à l'aide des différentes techniques chromatographiques telles que la chromatographie sur colonne ouverte, la filtration sur gel, la chromatographie liquide à haute pression, la chromatographie liquide à moyenne pression et la chromatographie liquide à basse pression. Par ailleurs, les structures des composés isolés ont été élucidées par des techniques spectroscopiques (UV, MS, RMN) et de méthode chimique (hydrolyse acide). En plus de ces techniques, certaines méthodes physiques (cristallographie par rayons-X, mesure de rotation optique) ont été réalisées pour confirmer certaines structures. Comme l'espèce Hypoestes serpens (Vahl) R. Br. se présente en deux variétés, une étude comparative a été effectuée. Cette étude avait montré que ces deux variétés ont une activité biologique similaire. Finalement, une technique analytique couplée, HPLC-UV-APC1-MS a permis de montrer la présence de toutes les substances isolées de la variété glabre dans la variété poilue. Second résumé Depuis des milliers d'almées, l'homme utilise les plantes pour se soigner. De nos jours, même avec le développement de la médecine moderne, la phytothérapie reste toujours la forme des soins de santé abordable et accessible pour la majorité des populations rurales des pays en développement. En outre, les plantes médicinales constituent une source potentielle de molécules biologiquement actives pour les industries pharmaceutiques et actuellement, on estime que 25% des médicaments commercialisés dans le monde sont à base de plantes Dans le cadre de la recherche des nouvelles molécules à intérêt thérapeutique qui pourraient devenir un médicament ou un modèle de structure ("lead compound") pour le développement de nouveaux médicaments, nous avons fait une étude sur l'espèce, Hypoestes serpens (Vahl) R. Br, plante utilisée en médecine traditionnelle malgache. Cette espèce existe en deux variétés, une glabre et une autre poilue qui sont tous utilisées dans la région sud-centre de Madagascar pour traiter la blennorragie. Par ailleurs, les tradipraticiens utilisent de préférence la variété poilue. Dans la première partie de ce présent travail, une investigation phytochimique de H serpens, variété glabre (variété moins utilisée) a d'abord été effectuée afm d'isoler et d'identifier le maximum des molécules biologiquement actives qu'elle contient. De ce fait, 17 composés dont 8 nouveaux ont été isolés. Les potentiels d'activités thérapeutiques des substances isolées ont ensuite été dépistés sur les différents cibles suivants.: deux souches de champignons (Cladosporium cucumerinum et Candida albicans), l'enzyme acétylcholinesterase et le radical DPPH. La deuxième partie de ce travail a été consacrée sur l'étude comparative des deux variétés (glabre et poilue) de H. serpens à la fois sur le plan biologique et sur le plan phytochimique. A l'issue de cette comparaison, nous avons constaté que l'utilisation de ces deux variétés en médecine traditionnelle malgache n'est pas un hasard ; les deux variétés avaient présenté une activité biologique très remarquable et contiennent les mêmes substances actives. Ces résultats démontrent les potentiels thérapeutiques de H serpens en médecine traditionnelle malgache et pourraient également encourager les tradipraticiens à utiliser la variété glabre tout en protégeant la variété poilue qui est en voie de disparition actuellement. En bref, l'investigation phytochimique de H. serpens justifiée par l'isolement et l'identification de certains de ses principes actifs ouvre la voie aux recherches des médicaments d'origine naturelle. Abstract In Madagascar, as in many developing countries, most people use plants to cure. A large number of plant species are employed in Malagasy traditional medicine. Moreover, most of these plants have been subject only very little scientific study. As part of a phytochemical investigation of plants used in Malagasy traditional medicine and in the search for new biologically active substances, Hypoestes serpens (Vah1) R.Br. (Acanthaceae) was investigated. This species exists in two varieties (glabrous and hairy) which are used in the south-center part of Madagascar to treat gonorrhoea. From the dichloromethane extract of the leaves of H. serpens (Vah1) R. Br. glabrous variety, 12 diterpenoids 8 of which were new, were isolated. They showed antifungal activity against the plant pathogen Cladosporium cucumerinum, in the direct TLC bioautography. Some of them also had activity against the yeast Candida athicans and inhibited acetylcholinesterase. The diterpenes are considered as the principal secondary metabolites of the genus Hypoestes. Fractionation of the methanol extract led to the isolation of 5 flavonoid glycosides, 4 of which were C-glycosides, never before identified in the Acanthaceae family. These flavonoids showed radical scavenging activity against DPPH. The fractionation and the purification of the extracts were achieved by different chromatographic techniques such as open-column chromatography, gel filtration, high- pressure liquid chromatography, medium-pressure liquid chromatography and low-pressure liquid chromatography. Moreover, the structures of the isolated compounds were elucidated by spectroscopic techniques (UV, MS, NMR) and chemical technique (acid hydrolysis). In addition, some physical methods (X-ray crystallography, measurement of optical rotation) were performed to confirm some structures. As the species Hypoestes serpens (Vah1) R. Br. is present in two varieties, a comparative study was carried out. This study showed that these two varieties had similar biological activity. Finally, a coupled analytical technique HPLC-UV-APCI-MS showed the presence of the same compounds in both the glabrous and hairy varieties.

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Introduction. Adherence to medication for asymptomatic disease is often low. We assessed factors associated with good adherence to medication for high blood pressure (HBP) in a country of the African region. Methods. A population-based survey of adults aged 25-64 years (N=1240 and participation rate=73%). Information was available in knowledge attitude and practice, SES and other variables. One question assessed adherence. Good adherence to treatment was defined as answering "I forget very rarely" vs "I forget on 1-2 days in a week" or "I forget on 3 or more days in a week". Results. In a univariate model adherence was strongly associated with belief that hypertension is a long-term disease (OR 2.6, p<0.001) and was negatively associated with concomitant use of traditional medicine (OR 0.36, p<0.005). The following variables tended to be associated with good adherence for HBP treatment: age, SES, BMI, belief that HBP is not symptomatic, going to government's clinics, medium stress level, controlled hypertension, taking statins. The following variables were not associated with good adherence for HBP treatment: education, higher BP, knowing people who had a stroke/MI, suffering from another chronic condition. In a multivariate model, pseudo R2 was 0.14. Conclusion. We built a multidimensional model including a wide range of variable. This model only predicted 14% of adherence variability. Variables associated with good adherence were demographics or related to knowledge attitude and practice. The latter one is modifiable by different type of interventions.

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A classic way of delaying drug resistance is to use an alternative when possible. We tested the malaria treatment Argemone mexicana decoction (AM), a validated self-prepared traditional medicine made with one widely available plant and safe across wide dose variations. In an attempt to reflect the real situation in the home-based management of malaria in a remote Malian village, 301 patients with presumed uncomplicated malaria (median age 5 years) were randomly assigned to receive AM or artesunate-amodiaquine [artemisinin combination therapy (ACT)] as first-line treatment. Both treatments were well tolerated. Over 28 days, second-line treatment was not required for 89% (95% CI 84.1-93.2) of patients on AM, versus 95% (95% CI 88.8-98.3) on ACT. Deterioration to severe malaria was 1.9% in both groups in children aged </=5 years (there were no cases in patients aged >5 years) and 0% had coma/convulsions. AM, now government-approved in Mali, could be tested as a first-line complement to standard modern drugs in high-transmission areas, in order to reduce the drug pressure for development of resistance to ACT, in the management of malaria. In view of the low rate of severe malaria and good tolerability, AM may also constitute a first-aid treatment when access to other antimalarials is delayed.

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De tout temps, hommes et femmes ont cherché par tous les moyens à développer, préserver ou recouvrer leurs propres capacités sexuelles mais également à stimuler le désir du partenaire. L?utilisation d?aphrodisiaques naturels a été l?un des recours les plus répandus. De nos jours, la commercialisation de nouvelles "love drugs" de synthèse, e.g. Viagra®, Cialis®, Levitra®, a remis au goût du jour les aphrodisiaques classiques et à relancer la recherche sur des molécules nouvelles. La pratique croissante de l?automédication, le matraquage publicitaire sur les aphrodisiaques naturels, la prolifération sur le marché de compléments alimentaires non contrôlés et l?absence de véritable législation accroissent les risques qui pèsent sur la santé publique. Dans le but d?évaluer les risques potentiels sur le consommateur de produits aphrodisiaques commercialisés, le développement et la validation d?une méthode rapide d?analyse qualitative et quantitative de la yohimbine dans ces préparations du marché sont exposés dans la première partie de ce travail. La yohimbine est un antagoniste ?2-adrénocepteur du système nerveux central et périphérique, elle est employée depuis plus d?un siècle dans le traitement des dysfonctionnements érectiles. Cette méthode analytique utilise la chromatographie liquide couplée à l?ultraviolet et à la spectrométrie de masse (LC-UV-MS) et au total, vingt préparations aphrodisiaques ont été étudiées. La dose journalière de yohimbine mesurée s?est révélée très variable selon les produits puisqu?elle varie de 1.32 à 23.16 mg. La seconde partie de ce travail concerne l?étude phytochimique et pharmacologique d?Erythroxylum vacciniifolium Mart. (Erythroxylaceae), une plante, appelée localement catuaba, utilisée dans la médecine traditionnelle brésilienne comme tonique et aphrodisiaque. Dans un premier temps, l?extrait alcaloïdique a été analysé par chromatographie liquide haute performance (HPLC) couplée soit à un détecteur UV à barrette d?iode (LC-UV-DAD), soit à un spectromètre de masse (LC-MS), ou soit à un spectromètre de résonance magnétique nucléaire (LC-RMN). L?interprétation de ces données spectrales enregistrées en ligne a permis d?obtenir des informations structurales et d?identifier partiellement près de 24 alcaloïdes appartenant à la classe des tropanes et potentiellement originaux. Par des méthodes classiques de chromatographie liquide sur l?extrait alcaloïdique de la plante, dix sept tropanes nouveaux ont ensuite été isolés dont les catuabines et leurs dérivés, et les vaccinines. Tous ces composés sont des tropane-diols ou triols estérifiés par au moins un groupe acide 1-méthyl-1H-pyrrole-2-carboxylique. Un de ces composés a été identifié comme un tropane N-oxyde. Toutes les structures ont été déterminées par spectrométrie de masse haute résolution et spectroscopie RMN multi-dimensionnelle. Parmi les nombreux tests biologiques réalisés sur ces tropanes, seuls les tests de cytotoxicité se sont révélés faiblement positifs pour certains de ces composés.<br/><br/>Throughout the ages, men and women have incessantly pursued every means to increase, preserve or recapture their sexual capacity, or to stimulate the sexual desire of selected individuals. One of the most recurrent methods has been the use of natural aphrodisiacs. Nowadays, the commercialization of new synthetic "love drugs", e.g. Viagra®, Cialis® and Levitra®, has fascinated the public interest and has led to a reassessment of classical aphrodisiacs and to the search for new ones. The practice of self-medication by an increasing number of patients, the incessant aggressive advertising of these herbal aphrodisiacs, the invasion of the medicinal market with uncontrolled dietary supplements and the absence of real directives amplifies the potential health hazards to the community. In order to evaluate the possible risks of commercialized aphrodisiac products on consumer health, the development and validation of a rapid qualitative and quantitative method for the analysis of yohimbine in these products, is reported in the first part of the present work. Yohimbine, a pharmacologically well-characterized ?2-adrenoceptor antagonist with activity in the central and peripheral nervous system, has been used for over a century in the treatment of erectile dysfunction. The analytical method is based on liquid chromatography coupled with ultraviolet and mass spectrometry (LC-UV-MS) and in total, 20 commercially-available aphrodisiac preparations were analyzed. The amount of yohimbine measured and expressed as the maximal dose per day suggested on product labels ranged from 1.32 to 23.16 mg. The second part of this work involved the phytochemical and pharmacological investigation of Erythroxylum vacciniifolium Mart. (Erythroxylaceae), a plant used in Brazilian traditional medicine as an aphrodisiac and tonic, and locally known as catuaba. With the aim of obtaining preliminary structure information on-line, the alkaloid extract was analyzed by high performance liquid chromatography (HPLC) coupled to diode array UV detection (LC-UVDAD), to mass spectrometry (LC-MS) and to nuclear magnetic resonance spectroscopy (LCNMR). Interpretation of on-line spectroscopic data led to structure elucidation and partial identification of 24 potentially original alkaloids bearing the same tropane skeleton. Seventeen new tropane alkaloids were then isolated from the alkaloid extract of the plant, including catuabines D to I, their derivatives and vaccinines A and B. All compounds were elucidated as tropane-diol or -triol alkaloids esterified by at least one 1-methyl-1H-pyrrole-2-carboxylic acid. One of the isolated compounds was identified as a tropane alkaloid N-oxide. Their structures were determined by high resolution mass spectrometry and multi-dimensional NMR spectroscopy. Among the numerous bioassays undertaken, only the cytotoxicity tests exhibited a weak positive activity of certain compounds.

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Résumé: Dans le but de rechercher de nouveaux composés naturels à intérêt thérapeutique, les extraits dichlorométhanique et méthanolique de Zanthoxylum zanthoxyloides (Lam.) Zepernick et Timler (Syn. Fagara zanthoxyloides L.) (Rutaceae), une brosse à dents africaine ont été soumis à un criblage chimique et biologique. Un dépistage des activités: antifongiques contre le champignon phytopathogène Cladosporium cucumerinum et la levure commensale responsable de mycoses chez l'homme Candida albicans, antibactérienne contre la bactérie opportuniste Bacillus subtilis, larvicide contre le moustique vecteur de la fièvre jaune Aedes aegypti et molluscicide contre Biomphalaria glabrata, un escargot impliqué dans la transmission de la schistosomiase urinaire a été réalisé. Les propriétés antiradicalaires et inhibitrices de l'acétylcholinestérase de ces extraits ont aussi été dépistées. Sur la base des résultats obtenus lors de ce screening, l'investigation phytochimique de ces extraits a été entreprise. Elle a abouti à l'isolement de 14 composés, actifs pour la majorité contre Cladosporium cucumerinum et Bacillus subtilis, dont la structure a été établie au moyen de méthodes spectroscopiques (UV, MS, IR, 1H- et 13C-NMR). Des méthodes chimiques (hydrolyse, acétylation) ont été requises pour la confirmation de structures. L'extrait dichlorométhanique a fourni un nouveau composé, un dérivé du phényléthane, ainsi que dix composés connus, dont trois dérivés du phénylpropane, un lignane, un alcaloïde de la famille des benzophénanthridines, un triterpène, deux amides phénoliques et deux amides oléfmiques. L'extrait méthanolique a fourni un nouveau composé avec une fonction endoperoxyde, qui avait montré une activité inhibitrice modérée de l'acétylcholinestérase, ainsi que l'hespéridine et un dérivé de la chélérythrine. Par ailleurs, l'analyse LC/UV/APC1-MS de cet extrait a permis de détecter on-une sept produits connus. Parmi ces composés, se trouvent l'acide divanilloylquinique, la chélérythrine et quatre de ses dérivés: norchélérythrin.e, 6-(2-oxybutyl) dihydrochélérythrine, 6-hydroxy-dihydrochélérythrine et avicine, ainsi qu'une amide phénolique, l'amottianamide. La présence de ces dérivés de la chélérythrine a été mise en évidence dans deux autres espèces du même genre lors d'une étude LC/UV/APCI-MS comparative. Les activités fongicides contre Cladosporium cucumerinum et Candida albicans et bactéricides contre Bacillus subtilis et Streptococcus mutans ATCC 25175, mises en évidence sur plaque CCM et par les tests de dilution dans l'agar de ces composés, permettent de justifier l'utilisation de Zanthoxylum zanthoxyloides (Lam.) Zepemick et Timler comme brosse à dents africaine. Les techniques couplées de pointe utilisées dans cette étude ont montré leur apport inestimable dans le domaine de la recherche phytochimique et les applications futures dans le domaine de déréplication d'extraits bruts. Abstract: With the aim of discovering new natural therapeutics, the dichloromethane and methanol extracts of the African toothbrush tree Zanthoxylum zanthoxyloides (Lam.) Zepernick et Timler (Syn. Fagara zanthoxyloides L.) (Rutaceae), were submitted to biological and chemical assays. The former included: the antifimgal activities of the extracts against the phytopathogenic fungus Cladosporium cucumerinum, the commensal yeast which causes human mycoses Candida albicans, the bactericidal activity against the opportunistic bacteria Bacillus subtilis, the larvicidal activity against the yellow fever-transmitting mosquito Aedes aegypti and the molluscicidal effect on the snail Biomphalaria glabrata involved in the transmission of urinary schistosomiasis. The antiradical and acetylcholinesterase-inhibiting properties of these extracts were also investigated. On the basis of these results, a phytochemical investigation of the dichloromethane and methanol extracts of Zanthoxylum zanthoxyloides was undertaken. Their fractionation led to the isolation of 14 compounds, the majority of which were active against Cladosporium cucumerinum and Bacillus subtilis, whose structures were elucidated by spectroscopic techniques (UV, MS, IR, 1H- and 13C-NMR). Chemical methods (hydrolysis, acetylation) were performed to confirm the structures. The dichloromethane extract yielded a new phenylethane derivative, together with ten known compounds: three phenylpropane derivatives, a lignan, a benzophenanthridine alkaloid, a triterpene and four phenolic and olefinic amides. The methanol extract yielded a new compound with an endoperoxide moiety, which showed moderate acetylcholinesterase-inhibiting activity, together with hesperidin and a chelerythrine derivative. Seven more compounds were detected on-line by LC/UV/APCI-MS. Among the compounds detected were divanilloylquinic acid, chelerythrine and four chelerythrine derivatives: norchelerythrine, 6-(2-oxybuty1)-dihydrochelerythrine, 6-hydroxy dihydrochelerythrine and avicine, together with the phenolic amide amottianamide. Most of the chelerythrine derivatives were also found in two other Zanthoxylum species following LC/UV/APCI-MS analysis. The antifungal activities against Cladosporium cucumerinum and Candida albicans and antibacterial activities against Bacillus subtilis and Streptococcus mutans ATCC 25175, may explain the utilization in traditional medicine of the roots of this plant as a toothbrush. The advanced hyphenated techniques used in this study showed their inestimable contribution to the field of phytochemical research and applications in the field of dereplication of crude extracts.

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The contribution of biodiversity and ecosystem services to our health care needs is significant, both for the development of modern pharmaceuticals (Chivian and Bernstein 2008; Newmann and Cragg 2007; see also chapter on contribution of biodiversity to pharmaceuticals in this volume) and for their uses in traditional medicine (WHO 2013). Long before the rise of pharmaceutical development, societies have been drawing on their traditional knowledge, skills and customary practices, using various resources provided to them by nature to prevent, diagnose and treat health problems. Today, these practices continue to inform health-care delivery at the level of local communities in many places around the world (WHO 2013). In socioecological contexts such as these, several resources used for food, cultural and spiritual purposes are also used as medicines (Unnikrishnan and Suneetha 2012). Traditional medicine practices provide more than health care to these communities; they are considered a way of life and are founded on endogenous strengths, including knowledge, skills and capabilities.

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The ancient Greek medical theory based on balance or imbalance of humors disappeared in the western world, but does survive elsewhere. Is this survival related to a certain degree of health care efficiency? We explored this hypothesis through a study of classical Greco-Arab medicine in Mauritania. Modern general practitioners evaluated the safety and effectiveness of classical Arabic medicine in a Mauritanian traditional clinic, with a prognosis/follow-up method allowing the following comparisons: (i) actual patient progress (clinical outcome) compared with what the traditional 'tabib' had anticipated (= prognostic ability) and (ii) patient progress compared with what could be hoped for if the patient were treated by a modern physician in the same neighborhood. The practice appeared fairly safe and, on average, clinical outcome was similar to what could be expected with modern medicine. In some cases, patient progress was better than expected. The ability to correctly predict an individual's clinical outcome did not seem to be better along modern or Greco-Arab theories. Weekly joint meetings (modern and traditional practitioners) were spontaneously organized with a modern health centre in the neighborhood. Practitioners of a different medical system can predict patient progress. For the patient, avoiding false expectations with health care and ensuring appropriate referral may be the most important. Prognosis and outcome studies such as the one presented here may help to develop institutions where patients find support in making their choices, not only among several treatment options, but also among several medical systems.

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BACKGROUND: "Virtual" autopsy by postmortem computed tomography (PMCT) can replace medical autopsy to a certain extent but has limitations for cardiovascular diseases. These limitations might be overcome by adding multiphase PMCT angiography. OBJECTIVE: To compare virtual autopsy by multiphase PMCT angiography with medical autopsy. DESIGN: Prospective cohort study. (ClinicalTrials.gov: NCT01541995) SETTING: Single-center study at the University Medical Center Hamburg-Eppendorf, Hamburg, Germany, between 1 April 2012 and 31 March 2013. PATIENTS: Hospitalized patients who died unexpectedly or within 48 hours of an event necessitating cardiopulmonary resuscitation. MEASUREMENTS: Diagnoses from clinical records were compared with findings from both types of autopsy. New diagnoses identified by autopsy were classified as major or minor, depending on whether they would have altered clinical management. RESULTS: Of 143 eligible patients, 50 (35%) had virtual and medical autopsy. Virtual autopsy confirmed 93% of all 336 diagnoses identified from antemortem medical records, and medical autopsy confirmed 80%. In addition, virtual and medical autopsy identified 16 new major and 238 new minor diagnoses. Seventy-three of the virtual autopsy diagnoses, including 32 cases of coronary artery stenosis, were identified solely by multiphase PMCT angiography. Of the 114 clinical diagnoses classified as cardiovascular, 110 were confirmed by virtual autopsy and 107 by medical autopsy. In 11 cases, multiphase PMCT angiography showed "unspecific filling defects," which were not reported by medical autopsy. LIMITATION: These results come from a single center with concerted interest and expertise in postmortem imaging; further studies are thus needed for generalization. CONCLUSION: In cases of unexpected death, the addition of multiphase PMCT angiography increases the value of virtual autopsy, making it a feasible alternative for quality control and identification of diagnoses traditionally made by medical autopsy. PRIMARY FUNDING SOURCE: University Medical Center Hamburg-Eppendorf.

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Pharmacogenomics is a field with origins in the study of monogenic variations in drug metabolism in the 1950s. Perhaps because of these historical underpinnings, there has been an intensive investigation of 'hepatic pharmacogenes' such as CYP450s and liver drug metabolism using pharmacogenomics approaches over the past five decades. Surprisingly, kidney pathophysiology, attendant diseases and treatment outcomes have been vastly under-studied and under-theorized despite their central importance in maintenance of health, susceptibility to disease and rational personalized therapeutics. Indeed, chronic kidney disease (CKD) represents an increasing public health burden worldwide, both in developed and developing countries. Patients with CKD suffer from high cardiovascular morbidity and mortality, which is mainly attributable to cardiovascular events before reaching end-stage renal disease. In this paper, we focus our analyses on renal function before end-stage renal disease, as seen through the lens of pharmacogenomics and human genomic variation. We herein synthesize the recent evidence linking selected Very Important Pharmacogenes (VIP) to renal function, blood pressure and salt-sensitivity in humans, and ways in which these insights might inform rational personalized therapeutics. Notably, we highlight and present the rationale for three applications that we consider as important and actionable therapeutic and preventive focus areas in renal pharmacogenomics: 1) ACE inhibitors, as a confirmed application, 2) VDR agonists, as a promising application, and 3) moderate dietary salt intake, as a suggested novel application. Additionally, we emphasize the putative contributions of gene-environment interactions, discuss the implications of these findings to treat and prevent hypertension and CKD. Finally, we conclude with a strategic agenda and vision required to accelerate advances in this under-studied field of renal pharmacogenomics with vast significance for global public health.