Genetic and Transmission Analysis of Helicobacter pylori Strains within a Family1

Point mutations, intragenic recombination, and introduction of foreign alleles enhanced strain diversity within the family

Using Macro-Arrays to Study Routes of Infection of Helicobacter pylori in Three Families

allowed tracing the spread of infection through populations on different continents but transmission pathways between individual humans have not been clearly described.To investigate person-to-person transmission, we studied three families each including one child with persistence of symptoms after antibiotic treatment. Ten isolates from the antrum and corpus of stomach of each family member were analyzed both by sequencing of two housekeeping genes and macroarray tests. from outside the family appeared to be probable in the transmission pathways. infection may be acquired by more diverse routes than previously expected

The Drosophila melanogaster host model

The deleterious and sometimes fatal outcomes of bacterial infectious diseases are the net result of the interactions between the pathogen and the host, and the genetically tractable fruit fly, Drosophila melanogaster, has emerged as a valuable tool for modeling the pathogen–host interactions of a wide variety of bacteria. These studies have revealed that there is a remarkable conservation of bacterial pathogenesis and host defence mechanisms between higher host organisms and Drosophila. This review presents an in-depth discussion of the Drosophila immune response, the Drosophila killing model, and the use of the model to examine bacterial–host interactions. The recent introduction of the Drosophila model into the oral microbiology field is discussed, specifically the use of the model to examine Porphyromonas gingivalis–host interactions, and finally the potential uses of this powerful model system to further elucidate oral bacterial-host interactions are addressed

Le sarcophage mérovingien de la gare Citram à Bordeaux

International audienceEn 1998, la fouille de l'ancien site de la gare routière de Bordeaux, la gare Citram, installée en 1931, a permis de faire sortir de l'oubli une portion de quartier connu essentiellement pour son voisinage avec le Palais Gallien et par la découverte au début du XIXe siècle, d'urnes funéraires associées à un cimetière augustéen.Si l'opération archéologique n'a pas permis d'approfondir notre connaissance du cimetière antique (sur ce point tout reste à faire), elle a révélé une occupation de la seconde moitié du Ier siècle après J.-C. jusqu'à la fin du XIXe siècle.Un sarcophage, stylistiquement attribuable au VIIe siècle, auxquels peuvent être ajoutés des fragments de cuves de sarcophages, témoignent d'une occupation durant le haut Moyen Age. La datation du squelette présent à l'intérieur, par le radiocarbone, nous permet de cerner sa mise en place entre la seconde moité du VIe siècle et la première moitié du VIIe siècle

Utilisation d’un microscope à émission de champ pour l’étude de l’adsorption des gaz sur le molybdène au niveau du plan cristallographique

Un microscope à émission de champ, muni d’un trou-sonde, a été utilisé dans la mesure des variations du travail d’extraction, ΔΦ, d’une pointe métallique missive monocristalline en molybdène. Les valeurs ΔΦ enregistrées au niveau de divers plans cristallins, lorsque les gaz résiduels (CO et H2) sont adsorbés à saturation sur une pointe préalablement décontaminée, ont été comparées avec les données de la littérature relatives à ΔΦH2 et ΔΦCO. Il a été conclu que les gaz résiduels ne subissent pas une simple coadsorption sur le molybdène mais qu’il se produit une interaction entre ces gaz conduisant à un complexe de surface

Increasing photovoltaic characteristics by incorporation of functionalized SWCNTs in solar cells based on P3HT : PCBM photoactive layer

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Improving the photovoltaic properties of organic solar cells by structuring the P3HT:PCBM photoactive layer with functionalized SWCNTs

International audienceThe optical and electrical properties of bulk polymer RR-P3HT (Regio-Regular Poly(3-hexylthiophene-2,5-diyl):PCBM (Methanofullerene Phenyl-C61-Butyric-Acid-Methyl-Ester) heterojunction incorporating single wall carbon nanotubes (SWCNTs) have been already reported by a number of research groups. We investigated a new approach to functionalize CarboLex single wall carbon nanotubes (SWCNTs-e) for increasing their dispersion in various solvents. The addition of SWCNTs-e in the matrix of P3HT:PCBM improves the photovoltaic (PV) characteristics. Results show that the photovoltaic parameters depend on the concentration of SWCNTs-e. The incorporation of low concentrations of SWCNTs-e in the photoactive layer increases the current density Jscbefore annealing. We attribute the improved performance to partial crystallisation of the RR-P3HT. As revealed by XRD studies and confirmed by the absorbance spectra which exhibit the characteristic 600 nm shoulder. Interestingly, we observed also that doping the P3HT:PCBM system with the functionalized SWCNTs increases Voc from 0.583 to 0.744 V.</p

Functionalized single wall carbon nanotubes improve the properties of polymer solar cells

International audienceThe optical and electrical properties of bulk polymer RR-P3HT (Regio-Regular Poly(3-hexylthiophène-2,5- diyl):PCBM (Methanofullerene Phenyl-C61-Butyric-Acid-Methyl-Ester) heterojunction incorporating single wall carbon nanotubes (SWCNTs) have been already reported by a number of research groups. We investigated a new approach to functionalize CarboLex single wall carbon nanotubes (SWCNTs-e) for increasing their dispersion in various solvents. The addition of SWCNTs-e in the matrix of P3HT:PCBM improves the photovoltaic (PV) characteristics. Results show that the photovoltaic parameters depend on the concentration of SWCNTs-e. The incorporation of low concentrations of SWCNTs-e in the photoactive layer increases the current density Jsc before annealing. We attribute the improved performance to partial crystallisation of the RR-P3HT. As revealed by XRD studies and confirmed by the absorbance spectra which exhibit the characteristic 600 nm shoulder. Interestingly, we observed also that doping the P3HT:PCBM system with the functionalized SWCNTs increases Voc from 0.583 to 0.744 V.</p