Ebola : des virus venus de la forêt

Depuis l'épidémie de fièvre hémorragique à virus Ebola (EBOV) en Afrique de l'Ouest, les agences internationales de sécurité alimentaire et de santé publique vétérinaire (OIE, FAO, ECDC, EFSA) analysent, sur la base des connaissances actuelles, les risques associés aux animaux et à leurs produits. Il en ressort un manque patent de données sur l'écologie de la maladie et sur la vulnérabilité des sociétés. (Résumé d'auteur

Beef value chain analysis in Zimbabwe

Conducted between September 2017 and April 2018, this analysis of the Zimbabwe beef value chain addressed the questions: What is the contribution of the value chain to economic growth? Is the economic growth generated by the value chain inclusive? Is the value chain socially sustainable? and, Is the value chain environmentally sustainable? The historical background for the Zimbabwe beef value chain is important as it provides context for the current situation. During the colonial and post-colonial period the key objective for the beef sector was intensive commercial farming and exploitation of market access opportunities under the Lome Convention. Following this Zimbabwe underwent a period of intensive land reform with large-scale transfer of farm land from Commercial (white) farmers to small-scale (black) farmers. Somewhere between 161,500 and 300,000 households have resettled on about 4.9 million hectares (Scoones et al, 2010). Commercial farms (white) have declined from 4,000 to about 725. However, various categories of 'new' (black) commercial farms have been developed pre-and post-land reform (11,000+ households). During this period the national disease control system failed and exports ended. Causes of this collapse include: co-habitation of buffalo and cattle; and, un-restrained movement of cattle from high-risk areas. Illegal exports and imports are also reported. Currently, Zimbabwe aims to reinstate centralised veterinary control to manage transboundary diseases. This has, so far, been unsuccessful with regular outbreaks of food-and-mouth disease occurring, including during the period of this research. A high proportion of the Zimbabwe population is poor (72.3%) and extremely poor (16.2%). Malnutrition affects 33.8% of children between 6-59 months of age. Rural Zimbabwe is poorer than urban areas by some margin (30.4% of households are extremely poor in rural areas vs 5.6% in urban areas). This drives migration and emigration. Livestock are essential for resilience and coping; cattle holding and maize yields closely correlated. Farms without livestock are the most vulnerable. Beef consumption is declining: from 13kg to 4 or 6kg per capita reflecting income changes and the availability of cheap chicken meat. Zimbabwe is a semi-arid country with 85% of the area receiving less than 800mm of rain a year. Resource endowment is high, but distribution skewed and sustainability is questioned by many. Key environmental issues include: land degradation, largely through poor land management; deforestation, through land clearance and fuel use; water scarcity, due to over extraction and urbanisation; pollution of water and air, through mining, urbanisation and intensive agriculture; biodiversity loss, through agricultural expansion and habitat loss; and, climate change and variability, resulting in higher temperatures and lower/variable rainfall

Phytoconstituents of leaf extracts of Ziziphus jujuba Mill. plants harvested in Tunisia

The present study aimed to determine the phytoconstituent compositions of the leaves of four Ziziphus jujuba ecotypes (Choutrana, Mahdia, Mahres and Sfax). The chromatographic peaks of 18 compounds, including nine major fatty acids, five sterols, two triterpene alcohols and two methysterols, were quantified by the capillary gaseous chromatography method. The major fatty acids identified were linolenic (42.04%) and palmitic (23.04%). Unsaturated fatty acids ranged between 53% and 60%. The predominant sterols (mg/100g) were β-sitosterol (40.36) and stigmasterol (24.18). Cycloartenol (68.55mg/100g) and citrostadienol (12.27mg/100g) were the major metylsterols. Methylene cycloartanol ranged between 1.2mg/100g (Sfax) and 1.5mg/100g (Mahdia). Total phenolic content measured by Folin-ciocalteux ranged from 3.97mg GAE/g to 6.04mg GAE/g. The predominant flavonoids identified by HPLC were apigenin (6.1mg/g) and rutin (1.91mg/g). The fatty acids and flavonoids in the Z. jujuba leaves were responsible for their therapeutic and pharmaceutical effects. This could explain why Tunisian people traditionally use it as medicine to treat several pathologies

Comparative static curing versus dynamic curing on tablet coating structures

International audienceCuring is generally required to stabilize film coating from aqueous polymer dispersion. This post-coating drying step is traditionally carried out in static conditions, requiring the transfer of solid dosage forms to an oven. But, curing operation performed directly inside the coating equipment stands for an attractive industrial application. Recently, the use of various advanced physico-chemical characterization techniques i.e., X-ray micro-computed tomography, vibrational spectroscopies (near infrared and Raman) and X-ray microdiffraction, allowed new insights into the film-coating structures of dynamically cured tablets. Dynamic curing end-point was efficiently determined after 4 h. The aim of the present work was to elucidate the influence of curing conditions on film-coating structures. Results demonstrated that 24 h of static curing and 4 h of dynamic curing, both performed at 60 degrees C and ambient relative humidity, led to similar coating layers in terms of drug release properties, porosity, water content, structural rearrangement of polymer chains and crystalline distribution. Furthermore, X-ray microdiffraction measurements pointed out different crystalline coating compositions depending on sample storage time. An aging mechanism might have occur during storage, resulting in the crystallization and the upward migration of cetyl alcohol, coupled to the downward migration of crystalline sodium lauryl sulfate within the coating layer. Interestingly, this new study clearly provided further knowledge into film-coating structures after a curing step and confirmed that curing operation could be performed in dynamic conditions

Comprehensive study of dynamic curing effect on tablet coating structure

International audienceThe dissolution method is still widely used to determine curing end-points to ensure long-term stability of film coatings. Nevertheless, the process of curing has not yet been fully investigated. For the first time, joint techniques were used to elucidate the mechanisms of dynamic curing over time from ethylcellulose (Aquacoat (R))-based coated tablets. X-ray micro-computed tomography (X mu CT), Near Infrared (NIR), and Raman spectroscopies as well as X-ray microdiffraction were employed as non-destructive techniques to perform direct measurements on tablets. All techniques indicated that after a dynamic curing period of 4 h, reproducible drug release can be achieved and no changes in the microstructure of the coating were any longer detected. X mu CT analysis highlighted the reduced internal porosity, while both NIR and Raman measurements showed that spectral information remained unaltered after further curing. X-ray microdiffraction revealed densification of the coating layer with a decrease in the overall coating thickness of about 10 pm as a result of curing. In addition, coating heterogeneity attributed to cetyl alcohol was observed from microscopic images and Raman analysis. This observation was confirmed by X-ray microdiffraction that showed that crystalline cetyl alcohol melted and spread over the coating surface with curing. Prior to curing, X-ray microdiffraction also revealed the existence of two coating zones differing in crystalline cetyl alcohol and sodium lauryl sulfate concentrations which could be explained by migration of these constituents within the coating layer. Therefore, the use of non-destructive techniques allowed new insights into tablet coating structures and provided precise determination of the curing end-point compared to traditional dissolution testing. This thorough study may open up new possibilities for process and formulation control

CD1 Gene Polymorphisms and Phenotypic Variability in X-Linked Adrenoleukodystrophy

X-linked adrenoleukodystrophy (X-ALD) is characterized by marked phenotypic variation ranging from adrenomyeloneuropathy (AMN) to childhood cerebral ALD (CCALD). X-ALD is caused by mutations in the ABCD1 gene, but no genotype-phenotype correlation has been established so far and modifier gene variants are suspected to modulate phenotypes. Specific classes of lipids, enriched in very long-chain fatty acids that accumulate in plasma and tissues from X-ALD patients are suspected to be involved in the neuroinflammatory process of CCALD. CD1 proteins are lipid- antigen presenting molecules encoded by five CD1 genes in human (CD1A-E). Association studies with 23 tag SNPs covering the CD1 locus was performed in 52 patients with AMN and 87 patients with CCALD. The minor allele of rs973742 located 4-kb downstream from CD1D was significantly more frequent in AMN patients (χ2 = 7.6; P = 0.006). However, this association was no longer significant after Bonferroni correction for multiple testing. The other polymorphisms of the CD1 locus did not reveal significant association. Further analysis of other CD1D polymorphisms did not detect stronger association with X-ALD phenotypes. Although the association with rs973742 warrants further investigations, these results indicate that the genetic variants of CD1 genes do not contribute markedly to the phenotypic variance of X-ALD

Site-specific conjugation for fully controlled glycoconjugate vaccine preparation

Glycoconjugate vaccines are formed by covalently link a carbohydrate antigen to a carrier protein whose role is to achieve a long lasting immune response directed against the carbohydrate antigen. The nature of the sugar antigen, its length, its ratio per carrier protein and the conjugation chemistry impact on both structure and the immune response of a glycoconjugate vaccine. In addition it has long been assumed that the sites at which the carbohydrate antigen is attached can also have an impact. These important issue can now be addressed owing to the development of novel chemoselective ligation reactions as well as techniques such as site-selective mutagenesis, glycoengineering, or extension of the genetic code. The preparation and characterization of homogeneous bivalent pneumococcal vaccines is reported. The preparation and characterization of homogeneous bivalent pneumococcal vaccines is reported. A synthetic tetrasaccharide representative of the serotype 14 capsular polysaccharide of Streptococcus pneumoniae has been linked using the thiol/maleimide coupling chemistry to four different Pneumococcal surface adhesin A (PsaA) mutants, each harboring a single cysteine mutation at a defined position. Humoral response of these 1 to 1 carbohydrate antigen/PsaA conjugates have been assessed in mice. Our results showed that the carbohydrate antigen-PsaA connectivity impacts the anti-carrier response and raise questions about the design of glycoconjugate vaccine whereby the protein plays the dual role of immunogen and carrier.S

Psychological Balance in High Level Athletes: Gender-Based Differences and Sport-Specific Patterns

OBJECTIVES: Few epidemiological studies have focused on the psychological health of high level athletes. This study aimed to identify the principal psychological problems encountered within French high level athletes, and the variations in their prevalence based on sex and the sport practiced. METHODS: Multivariate analyses were conducted on nationwide data obtained from the athletes' yearly psychological evaluations. RESULTS: A representative sample of 13% of the French athlete population was obtained. 17% of athletes have at least one ongoing or recent disorder, generalized anxiety disorder (GAD) being the most prevalent (6%), followed by non-specific eating disorders (4.2%). Overall, 20.2% of women had at least one psychopathology, against 15.1% in men. This female predominance applied to anxiety and eating disorders, depression, sleep problems and self-harming behaviors. The highest rates of GAD appeared in aesthetic sports (16.7% vs. 6.8% in other sports for men and 38.9% vs. 10.3% for women); the lowest prevalence was found in high risk sports athletes (3.0% vs. 3.5%). Eating disorders are most common among women in racing sports (14% vs. 9%), but for men were found mostly in combat sports (7% vs. 4.8%). DISCUSSION: This study highlights important differences in psychopathology between male and female athletes, demonstrating that the many sex-based differences reported in the general population apply to elite athletes. While the prevalence of psychological problems is no higher than in the general population, the variations in psychopathology in different sports suggest that specific constraints could influence the development of some disorders

Energy Resolution Performance of the CMS Electromagnetic Calorimeter

The energy resolution performance of the CMS lead tungstate crystal electromagnetic calorimeter is presented. Measurements were made with an electron beam using a fully equipped supermodule of the calorimeter barrel. Results are given both for electrons incident on the centre of crystals and for electrons distributed uniformly over the calorimeter surface. The electron energy is reconstructed in matrices of 3 times 3 or 5 times 5 crystals centred on the crystal containing the maximum energy. Corrections for variations in the shower containment are applied in the case of uniform incidence. The resolution measured is consistent with the design goals

Bacteria isolated from lung modulate asthma susceptibility in mice

Asthma is a chronic, non-curable, multifactorial disease with increasing incidence in industrial countries. This study evaluates the direct contribution of lung microbial components in allergic asthma in mice. Germ-Free and Specific-Pathogen-Free mice display similar susceptibilities to House Dust Mice-induced allergic asthma, indicating that the absence of bacteria confers no protection or increased risk to aeroallergens. In early life, allergic asthma changes the pattern of lung microbiota, and lung bacteria reciprocally modulate aeroallergen responsiveness. Primo-colonizing cultivable strains were screened for their immunoregulatory properties following their isolation from neonatal lungs. Intranasal inoculation of lung bacteria influenced the outcome of allergic asthma development: the strain CNCM I 4970 exacerbated some asthma features whereas the pro-Th1 strain CNCM I 4969 had protective effects. Thus, we confirm that appropriate bacterial lung stimuli during early life are critical for susceptibility to allergic asthma in young adults