Caractérisation moléculaire des Penicillium contaminants de l'alimentation

*INRA, Centre de Versailles (FRA) Diffusion du document : INRA, Centre de Versailles (FRA) Diplôme : DE

STUDY OF THE ELECTRICAL CONDUCTIVITY OF GRAPHITE FELT EMPLOYED AS A POROUS ELECTRODE

The objective of the present work is to study the variation of the electrode distribution potential under electrical conductivity variation of graphite felt RVG 4000 ( Le Carbone Lorraine) when submitted to a mechanical compression. Experimental and theoretical studies show that this electrical conductivity variation can changes the electrode potential distribution E(x) working under limiting current conditions. This may occur when graphite felt is confined in an electrochemical reactor compartment or simply when it is submitted to a force performed by an electrolyte percolation in a turbulent flow. This investigation can contribute to the improvement of electrochemical cells that may use this material as an electrode. Finally, one modification is suggested in the equation that gives the electrode potential distribution E(x) - E(0). In this case the parameter L (thickness in metal porous electrodes) is substituted for Lf = Li (1-j), where j corresponds to the reduction factor of the initial thickness Li

Microbiological assessment of four probiotic feed supplements used by the dairy industry in New Zealand

Since Metchnikoff’s publication ‘‘The Prolongation of Life’’ (Metchnikoff 1908) proposed the use of live bacteria to improve health, a precise definition of probiotics has yet to be formulated, however a widely held definition is ‘‘live microorganisms which, when administered in adequate amounts, confer a health benefit on the host’’ (FAO/WHO 2002). However, an on-going challenge with using probiotics is maintaining their viability while they are stored and sold. This challenge is compounded when probiotics are used in agriculture as feed supplements, since it may not be economical to use freeze drying or refrigeration to maintain the viability of microbes in a product. We analysed four agricultural probiotic feed supplements used by the New Zealand dairy industry, to estimate the number of live probiotic microbes in each product using a combination of culture techniques, particle size analysis and live/dead staining

Campylobacter coli cultured from the stools of a patient with immunoproliferative small intestinal disease

International audienceCampylobacter has been associated with immunoproliferative small intestinal disease (IPSID), on the basis of 16S rDNA sequencing, in situ hybridization, and immunohistochemistry. Here, for the first time, we have cultured Campylobacter from the stools of a patient with IPSID. Phenotypic analysis and whole genome sequencing identified Campylobacter coli. PCR on a IPSID tissue biopsy sample was positive for Campylobacter coli and negative for Campylobacter jejuni. These findings further support a causative role for Campylobacter in the development of IPSID

Mobility and the spread of human immunodeficiency virus into rural areas of West Africa.

BACKGROUND: In eastern and southern Africa, the human immunodeficiency virus (HIV) epidemic appeared first in urban centres and then spread to rural areas. Its overall prevalence is lower in West Africa, with the highest levels still found in cities. Rural areas are also threatened, however, because of the population's high mobility. We conducted a study in three different communities with contrasting infection levels to understand the epidemiology of HIV infection in rural West Africa. METHOD: A comparative cross-sectional study using a standardized questionnaire and biological tests was conducted among samples in two rural communities of Senegal (Niakhar and Bandafassi, 866 and 952 adults, respectively) and a rural community of Guinea-Bissau (Caio, 1416 adults). We compared the distribution of population characteristics and analysed risk factors for HIV infection in Caio at the individual level. RESULTS: The level of HIV infection was very low in Niakhar (0.3%) and Bandafassi (0.0%), but 10.5% of the adults in Caio were infected, mostly with HIV type 2 (HIV-2). Mobility was very prevalent in all sites. Short-term mobility was found to be a risk factor for HIV infection among men in Caio (adjusted odds ratio (aOR) = 2.06; 95% CI: 1.06-3.99). Women from Caio who reported casual sex in a city during the past 12 months were much more likely to be infected with HIV (aOR = 5.61 95% CI: 1.56-20.15). Short-term mobility was associated with risk behaviours at all sites. CONCLUSIONS: Mobility appears to be a key factor for HIV spread in rural areas of West Africa, because population movement enables the virus to disseminate and also because of the particularly risky behaviours of those who are mobile. More prevention efforts should be directed at migrants from rural areas who travel to cities with substantial levels of HIV infection