Les arboviroses tropicales émergentes en France (dengue et chikungunya) : étude du rôle du pharmacien d'officine dans la lutte anti-vectorielle (Thèse d'exercice de Pharmacie)

En 2005, l’épidémie de chikungunya qui a sévi sur l’île de la Réunion a marqué les esprits. Depuis, avec l’arrivée d’un moustique pouvant être le vecteur de cette maladie en France ; Aedes albopictus, la problématique s’est élargie. Venu initialement d’Italie, ce moustique se propage en effet le long du littoral méditerranéen français et peut véhiculer les virus de la dengue et du chikungunya pour les transmettre à l’homme. Pour éviter l’émergence de ces arboviroses, il faut donc lutter contre le moustique tigre sous deux aspects : l’aspect de la nuisance mais aussi et surtout, l’aspect de sa capacité et de sa compétence vectorielle. Les différents messages de la lutte anti-vectorielle peuvent apparaître ambigus et leur utilité est parfois remise en question. Ainsi, le pharmacien est un acteur de santé incontournable, sollicité par les populations des régions endémiques pour disposer de plus d’informations et savoir comment se protéger contre Aedes albopictus. Une étude a donc été réalisée pour réaliser un état des lieux des connaissances des pharmaciens d’officine dans ce domaine, dans la ville de Marseille. Or, les enseignements tirés de cette enquête ont été la mise en évidence des lacunes pouvant porter préjudice à la bonne information et donc éducation communautaire. Un plan d’actions est donc proposé pour améliorer la prise en charge

Capillary infiltration of hexadecane in packed SiC powder and in SiC/SiC preforms: Pore description and calculation of molten Si infiltration

International audienceA SiC/SiC-Si composite can be synthesized by molten silicon infiltration in a SiC preform impregnated with a slurry of SiC powder. The kinetics of molten silicon infiltration in such a porous material are unknown, and the experimental measurement is complex. The calculation of the rise kinetics for a liquid in a porous material is possible by applying the Washburn modified equation with an accurate description of the pores. The monitoring of the mass and front height variations during hexadecane infiltration in a submicronic SiC packed powder and in a preform filled with a SiC powder was used to characterize the porosity. In the case of a fibrous preform, the residual porosity is composed of inter-grain pores and cracks formed during the drying of the slurry. The results of this study suggest that the liquid progresses first in the inter-grain porosity of the powder. The rise kinetics of molten silicon into a preform were then evaluated by calculation based on the pore description obtained from hexadecane capillary infiltration experiments

Examination of the interaction between liquid silicon and bulk silicon carbide

International audienceLittle information is available about the evolution of SiC in presence of molten silicon. In this context, two kinds of experiments relative to the interaction between SiC substrates and molten Si were performed between 1450 and 1600°C with: 1) dense α-SiC bars and 2) dense α-SiC pellets coated with a β-SiC layer deposited by CVD. The results obtained indicate that an important crystal growth occurs in any cases. Large and facetted SiC crystals have grown on the surface of the SiC substrates and on the whole surface of molten silicon. These crystals are formed by dissolution-growth mechanism of SiC substrates with kinetics depending on the temperature. Low thermal gradients within the samples and between the inner parts and/or the surface of the samples could noticeably promote the evolution of the system by generating a carbon flux. The interaction between molten silicon and SiC is of importance because it could have some effects on the physical and chemical properties of the materials. It is well known that large grains are deleterious for mechanical properties

Development of RT-semi-nested PCR for detection of hepatitis A virus in stool in epidemic conditions.

The purpose of this study was to determine the efficiency of semi-nested PCR in detecting hepatitis A virus (HAV) RNA. During a 2-year period (1990-1991), HAV RNA was searched for in shellfish from the French Brittany coasts using cRNA and vRNA probes. In January 1992, at the time of a hepatitis A outbreak, 28 stool samples were collected from infected patients (18 adults, 10 children) with anti-HAV IgM. Four samples from subjects with negative HAV serology were used as negative controls. Nucleic acid amplification (reverse-transcription-semi-nested PCR) was performed to detect HAV in stool. HAV RNA was purified by phenol-chloroform extraction and converted to cDNA using reverse transcriptase (Mu-MLV). After amplification, PCR products were visualized on an ethidium-bromide-stained gel and confirmed by hybridization with a specific digoxigenin-labelled oligoprobe. Samples were also studied by molecular hybridization with cRNA and vRNA probes. After onset of the illness, HAV RNA was detected over a longer time period by semi-nested PCR (16/28) than by hybridization (0/28). Even though biological diagnosis of hepatitis A will continue to rely on the detection of anti-HAV IgM, PCR should be useful in certain clinical cases (diagnosis of relapse) and for epidemiological and environmental monitoring of viruses

Inter-annual species-level variations in an abyssal polychaete assemblage (Sta. M, NE Pacific, 4000 m)

Understanding the dynamics of abyssal community structure and function has become increasingly important as deep-sea resource exploitation and climate change pressures are expected to ramp up. This time-series study investigates macrofaunal polychaete dynamics at a station in the North East Pacific (Sta. M; 35˚ N 123˚ W, 4000 m, 1991-2011). Infaunal polychaete species were identified and their proxy biomass and proxy energy use rate estimated. The assemblage comprised 167 species, having a composition consistent with other abyssal areas globally. Significant changes in univariate and multivariate parameters (rank abundance distribution, Simpson’s diversity index, and species and functional group composition) were detected across 1991-2011. However, no change in biomass or energy use rate was apparent through the time-series. The largest changes in the polychaete assemblage coincided with both an increase in sinking particulate organic carbon flux to the seafloor in 2007, and a 40 km relocation of the sampling location to a site 100 m shallower, preventing a conclusive assessment of which might drive the observed variation. Analyses prior to the change of sampling location showed that the polychaete assemblage composition dynamics were primary driven by food supply variation. Changes in several species were also lagged to changes in POC flux by 4 to 10 months. The polychaete fauna exhibited a significant positive relationship between total density and total energy use rate, suggesting population-level tracking of a common resource (e.g. POC flux food supply). Neither compensatory nor energetic zero-sum dynamics were detected among the polychaete assemblage, but the results suggest that the latter occur in the macrofaunal community as a whole. The results do indicate (a) potential control of species composition, and the density of individual key species, by food supply, when the time-series prior to the sampling location was analysed separately, and (b) generally sensitive detection of environmental change by species-level analysis of the abyssal polychaete assemblage

HIV infection and severe malnutrition: a clinical and epidemiological study in Burkina Faso.

OBJECTIVE: To define a clinical profile indicative of HIV infection in a population of severely malnourished children in Burkina Faso. A total of 433 children (average age, 19 months) were recruited at the Sanou Souro National Hospital, Bobo Dioulasso, Burkina Faso. RESULTS: Sixty-three per cent presented with marasmus, 13% with kwashiorkor and 24% with both forms of malnutrition. The prevalence of HIV infection in children aged over 12 months was 13.8%, with a marked predominance of HIV-1 (95.8%). Mother-to-child transmission was proven in 77% of the cases; in 10% of the observed paediatric AIDS cases, transmission may have occurred through multi-injections with contaminated equipment. Marasmus was the form of malnutrition most frequently associated with HIV (P < 0.001); its severity was exacerbated by HIV infection. Adenopathy (P < 0.0001), oral candidiasis (P < 0.0006), skin disorders (P < 0.01) and hepatomegaly (P = 0.01) appeared to be significantly related to HIV infection. Discriminant analysis revealed that the presence of adenopathies was the strongest indicator symptom of HIV infection. Multivariate analysis revealed that a clinical profile of marasmus, adenopathies and oral candidiasis (specificity, 82%) was indicative of HIV infection in this population. The short-term clinical prognosis was poor and usually led to the death of the child when seropositive (P < 0.001). CONCLUSIONS: Among children exhibiting severe malnutrition, HIV-positive children are distinguished by a high horizontal transmission rate, a high specific clinical profile and a very poor prognosis