Analysis of additivity and synergism in the anti-plasmodial effect of purified compounds from plant extracts

In the search for antimalarials from ethnobotanical origin, plant extracts are chemically fractionated and biological tests guide the isolation of pure active compounds. To establish the responsibility of isolated active compound(s) to the whole antiplasmodial activity of a crude extract, the literature in this field was scanned and results were analysed quantitatively to find the contribution of the pure compound to the activity of the whole extract. It was found that, generally, the activity of isolated molecules could not account on their own for the activity of the crude extract. It is suggested that future research should take into account the “drugs beside the drug”, looking for those products (otherwise discarded along the fractionation process) able to boost the activity of isolated active compounds

A second generation human haplotype map of over 3.1 million SNPs

We describe the Phase II HapMap, which characterizes over 3.1 million human single nucleotide polymorphisms (SNPs) genotyped in 270 individuals from four geographically diverse populations and includes 25-35% of common SNP variation in the populations surveyed. The map is estimated to capture untyped common variation with an average maximum r(2) of between 0.9 and 0.96 depending on population. We demonstrate that the current generation of commercial genome-wide genotyping products captures common Phase II SNPs with an average maximum r(2) of up to 0.8 in African and up to 0.95 in non-African populations, and that potential gains in power in association studies can be obtained through imputation. These data also reveal novel aspects of the structure of linkage disequilibrium. We show that 10-30% of pairs of individuals within a population share at least one region of extended genetic identity arising from recent ancestry and that up to 1% of all common variants are untaggable, primarily because they lie within recombination hotspots. We show that recombination rates vary systematically around genes and between genes of different function. Finally, we demonstrate increased differentiation at non-synonymous, compared to synonymous, SNPs, resulting from systematic differences in the strength or efficacy of natural selection between populations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62863/1/nature06258.pd

Type A aortic dissection in aneurysms having modelled pre-dissection maximum diameter below 45 mm: should we implement current guidelines to improve the survival benefit of prophylactic surgery?

Current guidelines recommend prophylactic replacement of the ascending aorta at an aneurysmal diameter of >55 mm to prevent acute Type A aortic dissection (TAAD) in non-Marfan patients. Several publications have challenged this threshold, suggesting that surgery should be performed in smaller aneurysms to prevent this devastating disease. We reviewed our experience with measuring aortic size at the time of TAAD to validate the existing recommendation for prophylactic ascending aorta replacement. All patients who had been admitted for TAAD to our emergency department from 2014 to 2019 and underwent ascending aorta replacement were included. Marfan patients were excluded. The maximum diameter of the dissected aorta was measured preoperatively using CT scan. We estimated the aortic diameter at the time of dissection to be 7 mm smaller than the measured maximum diameter of the dissected aorta (modelled pre-dissection diameter). Overall, 102 patients were included. Of these, 67 were male (65.6%) and 35 were female (34.4%), and the cohort's mean age was 65 ± 12.1 years. In addition, 66% were treated for arterial hypertension. The mean maximum modelled pre-dissection diameter was 39.6 ± 4.8 mm: 39.1 ± 5.1 mm in men and 40.7 ± 2.8 mm in women (P = 0.1). The cumulative 30-day mortality rate was 19.6% (20/102). TAAD occurred at a modelled aortic diameter below 45 mm in 87.7% of our patients. Therefore, the current aortic diameter threshold of 55 mm excludes ∼99% of patients with TAAD from prophylactic replacement of the ascending aorta. The maximum diameter of the ascending aorta warrants reappraisal and this parameter should be a distinct part of a personalized decision-making process that also takes into account age, gender and body surface area to establish the surgical indication for preventive aorta replacement aimed to improve the survival benefit of this procedure

Chemical composition of the essential oil from algerian genista quadriflora munby and determination of its antibacterial and antifungal activities

International audienceThe hydrodistilled oil of the aerial parts from Genista quadriflora growing in Algeria was analyzed by gas chromatography-flame ionization detection (GC/FID) and gas chromatography-mass spectrometry (GC/MS). Altogether 222 volatile substances, representing around 77% of the essential oil was identified. The major constituents were the sesquiterpenes muurolan-4,7-peroxide (19.42%), amorpha-4,9-dien-2-ol (10.40%), alpha-cadinol (2.29%), caryophyllene oxide (1.47%) and germacra-4(15),5,10(14)-trien-1-alpha-ol (1.39%). Fatty acids were the second most abundant compounds of the essential oil detected with dodecanoic acid (lauric) (3.14%), hexadecanoic acid (palmitic) (2.49%) and tetradecanoic acid (myristic) (1.12%) as main components. The volatile oil was screened in vitro for antibacterial and antifungal activities using dilution and disc diffusion methods. Thus, the crude essential oil exhibited a marked antifungal activity against Fusarium oxysporun and a significant inhibition activity was registered towards a Gram-negative bacterium Proteus mirabilis. Substantial antibacterial activity was also recorded against Gram-positive bacteria with MIC: 0.9 +/- 0.1 and 1.7 +/- 0.3 mg/ml for Staphylococcus aureus suggesting the possibility to use of G. quadriflora essential oil in the development of new drugs for treatment of infectious diseases

C38 - Évaluation in vitro de l'activité antibactérienne d'un pansement chargé d'extraits de plantes

Introduction : Les plaies infectées constituent un problème de santé publique du fait qu’elles peuvent prolonger la durée d’une hospitalisation. Les pansements utilisés dans leurs prises en charge contiennent souvent des antibactériens comme l’ion argent. Cette étude, dans le cadre de la valorisation des plantes Sénégalaises utilise comme actif antibactérien un extrait de noyau de mangue et d’avocat sur un support textile PET enduit d’un film plastique à base d’amidon. Matériel et Méthodes : Les concentrations minimales inhibitrices d'extraits de plantes sur les souches testées ont été réalisées dans des boîtes de Pétri. Un mélange des extraits actifs à part égale d'extrait d'éther de pétrole de noyau d'avocat (Persea americana) et d'extrait méthanolique de noyau de mangue (Mangifera indica) a ensuite été testé. Ce mélange a été incorporé dans un pansement constitué d'un textile et d'un film plastique à base d’amidon contenant de la carboxyméthylcellulose et du polymère de bêta-cyclodextrine comme absorbant. Des tests Kirby-Bauer et kill time ont finalement été réalisés sur le pansement contenant le mélange d'extraits. Résultats/discussion : Le mélange avocat/mangue 1:1 incorporé dans le pansement a induit une réduction logarithmique de 3,5 log de Staphylococcus aureus (ATCC 6538). Cependant, en raison d'une activité plus faible observée contre les bactéries à Gram négatif (Pseudomonas aeruginosa) et les champignons (Candida albicans), le pansement a donc pu être indiqué sur des plaies non surinfectées (absence de Pseudomonas). En ce qui concerne la capacité d'absorption (1,72 g/100 cm2), ce type de pansement est un pansement à absorption moyenne et pourrait être recommandé pour les plaies aiguës et chroniques à faible activité exsudative au stade bourgeonnant. Nos résultats démontrent l'efficacité du pansement textile avec des extraits de plantes

Ethnopharmacological study of plants used on Raiatea and Tahaa islands in French Polynesia

International audienc