34 research outputs found

    The use of genomic signature distance between bacteriophages and their hosts displays evolutionary relationships and phage growth cycle determination

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Bacteriophage classification is mainly based on morphological traits and genome characteristics combined with host information and in some cases on phage growth lifestyle. A lack of molecular tools can impede more precise studies on phylogenetic relationships or even a taxonomic classification. The use of methods to analyze genome sequences without the requirement for homology has allowed advances in classification.</p> <p>Results</p> <p>Here, we proposed to use genome sequence signature to characterize bacteriophages and to compare them to their host genome signature in order to obtain host-phage relationships and information on their lifestyle. We analyze the host-phage relationships in the four most representative groups of Caudoviridae, the dsDNA group of phages. We demonstrate that the use of phage genomic signature and its comparison with that of the host allows a grouping of phages and is also able to predict the host-phage relationships (lytic <it>vs</it>. temperate).</p> <p>Conclusions</p> <p>We can thus condense, in relatively simple figures, this phage information dispersed over many publications.</p

    Measurements of the leptonic branching fractions of the τ\tau

    Get PDF
    Data collected with the DELPHI detector from 1993 to 1995 combined with previous DELPHI results for data from 1991 and 1992 yield the branching fractions B({\tau \rightarrow \mbox{\rm e} \nu \bar{\nu}}) = (17.877 \pm 0.109_{stat} \pm 0.110_{sys} )\% and B(τ→ΌΜΜˉ)=(17.325±0.095stat±0.077sys)%B({\tau \rightarrow \mu \nu \bar{\nu}}) = (17.325 \pm 0.095_{stat} \pm 0.077_{sys} )\%

    Search for scalar fermions and long-lived scalar leptons at centre-of-mass energies of 130 GeV to 172 GeV

    Get PDF
    Data taken by DELPHI during the 1995 and 1996 LEP runs have been used to search for the supersymmetric partners of electron, muon and tau leptons and of top and bottom quarks. The observations are in agreement with standard model predictions. Limits are set on sfermion masses. Searches for long lived scalar leptons from low scale supersymmetry breaking models exclude stau masses below 55~GeV/c2^2 at the 95\% confidence level, irrespective of the gravitino mass

    Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets

    Get PDF

    LWIR quantum efficiency measurements using a calibrated MCT photodiode read by a cryo-HEMT-based amplifier

    Full text link
    International audienceWe present a new development for the measurement of the Quantum Efficiency (QE) of a Mercury Cadmium Telluride (HgCdTe or MCT) detector array in the long wave infrared (LWIR) spectral band. To measure the incident photon flux on the detector, CEA-LETI has designed and produced a calibrated MCT photodiode which, under the test setup conditions used for the QE measurement, delivers a total (dark plus photonic) current of 1nA at 60K. The readout of such a low level of current makes a standard room temperature amplifier inconvenient due to the length of the wires between the focal plane (FP) at cold and the outside of the cryostat (>2m in the current cryostat). A much better approach is to use High Electron Mobility Transistors (Cryo-HEMTs), optimized by CNRS/C2N laboratory for ultra-low noise at very low temperatures (<1K). We have developed a Cryo-HEMT-based transimpedance amplifier to readout the photonic current of the calibrated MCT chip. The paper describes the calibrated photodiode, the Cryo-HEMT amplifier and the test setup, and shows the results of the QE measurements of the LWIR detector

    Colorectal cancer specific conditions promote Streptococcus gallolyticus gut colonization

    Full text link
    International audienceColonization by Streptococcus gallolyticus subsp. gallolyticus (SGG) is strongly associated with the occurrence of colorectal cancer (CRC). However, the factors leading to its successful colonization are unknown, and whether SGG influences the oncogenic process or benefits from the tumor-prone environment to prevail remains an open question. Here, we elucidate crucial steps that explain how CRC favors SGG colonization. By using mice genetically prone to CRC, we show that SGG colonization is 1,000-fold higher in tumor-bearing mice than in normal mice. This selective advantage occurs at the expense of resident intestinal enterococci. An SGG-specific locus encoding a bacteriocin ("gallocin") is shown to kill enterococci in vitro. Importantly, bile acids strongly enhance this bacteriocin activity in vivo, leading to greater SGG colonization. Constitutive activation of the Wnt pathway, one of the earliest signaling alterations in CRC, and the decreased expression of the bile acid apical transporter gene Slc10A2, as an effect of the Apc founding mutation, may thereby sustain intestinal colonization by SGG. We conclude that CRC-specific conditions promote SGG colonization of the gut by replacing commensal enterococci in their niche

    Lack of anti-inflammatory effect exerted by single drugs.

    Full text link
    <p><b>a.</b> Representative microphotograhs of microglia and DAPI at 3 weeks after co-treatment with THA alone or plus single components of the neuroprotective combinations (CD1 and CD2): Aliretinoin (Ali), Mefloquine (Meflo) and Pranlukast (Pran) (n = 5). <i>Right panels</i> are profile drawings of microglia showing the ameboid-like or ramified shape acquired after each treatment. <b>b.</b> Bar graph showing the microglial reactivity of each experimental condition by measuring the immunofluorescence intensity of Iba-1 in the ventral horn of each spinal cord slice. (mean±SEM, n = 5) (*p<0.05; by Dunnett’s post-hoc test vs THA condition).</p

    Lack of neuroprotection exerted by single drugs.

    Full text link
    <p><b>a.</b> Representative microphotograhs of SMI-32 at 4 weeks after excitotoxic treatment stained MNs after co-treatment with THA plus CD1 and CD2 components: Aliretinoin (Ali), Mefloquine (Meflo) and Pranlukast (Pran). <b>b</b>. Bar graph showing the number of SMI-32 positive neurons in the ventral horn of each spinal cord slice obtained after each treatment. (mean±SEM, n = 5). No significant differences comparing each drug treatment by Dunnett’s post-hoc test vs THA condition.</p

    Reduction of microgliosis by drug combinations CD1 and CD2.

    Full text link
    <p><b><i>a</i>.</b> Schematic drawing indicating the site of analysis (white frame) of microgliosis at the ventral horn of the spinal cord slice. <b>b</b>. <i>Top panels</i> are representative microphotographs showing microglia stained with anti-Iba1 (green) at 3 weeks post-THA treatment alone or co-treated with each drug combination or riluzole. <i>Middle panels</i> are profile drawings of microglia showing the ameboid-like or ramified shape acquired after each treatment. <i>Bottom panels</i>, representative microphotographs of the merge fluorescent staining with anti-Iba1, DAPI and MNs stained with SMI-32. Scale bar, 20 ÎŒm. <b>c.</b> Bar graph showing the microglial reactivity of each experimental condition by measuring the immunofluorescence intensity of Iba-1 in the ventral horn of each spinal cord slice. (mean±SEM, n = 5) (***p<0.001; by Dunnett’s post-hoc test vs THA condition).</p
    corecore