Project description:We characterized the bacterial diversity of chlorinated drinking water from three surface water treatment plants supplying the city of Paris, France. For this purpose, we used serial analysis of V6 ribosomal sequence tag (SARST-V6) to produce concatemers of PCR-amplified ribosomal sequence tags (RSTs) from the V6 hypervariable region of the 16S rRNA gene for sequence analysis. Using SARST-V6, we obtained bacterial profiles for each drinking water sample, demonstrating a strikingly high degree of biodiversity dominated by a large collection of low-abundance phylotypes. In all water samples, between 57.2-77.4% of the sequences obtained indicated bacteria belonging to the Proteobacteria phylum. Full-length 16S rDNA sequences were also generated for each sample, and comparison of the RSTs with these sequences confirmed the accurate assignment for several abundant bacterial phyla identified by SARST-V6 analysis, including members of unclassified bacteria, which account for 6.3-36.5% of all V6 sequences. These results suggest that these bacteria may correspond to a common group adapted to drinking water systems. The V6 primers used were subsequently evaluated with a computer algorithm to assess their hybridization efficiency. Potential errors associated with primer-template mismatches and their impacts on taxonomic group detection were investigated. The biodiversity present in all three drinking water samples suggests that the bacterial load of the drinking water leaving treatment plants may play an important role in determining the downstream community dynamics of water distribution networks.
Project description:We characterized the bacterial diversity of chlorinated drinking water from three surface water treatment plants supplying the city of Paris, France. For this purpose, we used serial analysis of V6 ribosomal sequence tag (SARST-V6) to produce concatemers of PCR-amplified ribosomal sequence tags (RSTs) from the V6 hypervariable region of the 16S rRNA gene for sequence analysis. Using SARST-V6, we obtained bacterial profiles for each drinking water sample, demonstrating a strikingly high degree of biodiversity dominated by a large collection of low-abundance phylotypes. In all water samples, between 57.2-77.4% of the sequences obtained indicated bacteria belonging to the Proteobacteria phylum. Full-length 16S rDNA sequences were also generated for each sample, and comparison of the RSTs with these sequences confirmed the accurate assignment for several abundant bacterial phyla identified by SARST-V6 analysis, including members of unclassified bacteria, which account for 6.3-36.5% of all V6 sequences. These results suggest that these bacteria may correspond to a common group adapted to drinking water systems. The V6 primers used were subsequently evaluated with a computer algorithm to assess their hybridization efficiency. Potential errors associated with primer-template mismatches and their impacts on taxonomic group detection were investigated. The biodiversity present in all three drinking water samples suggests that the bacterial load of the drinking water leaving treatment plants may play an important role in determining the downstream community dynamics of water distribution networks. 3 different drinking water samples (Orly, Ivry, Joinville drinking water sample)
Project description:Water immersion insertion has been documented to decrease procedure-related discomfort during colonoscopy. There was used warm water infusion for colonoscope insertion in most of the water immersion colonoscopy trials.
The investigators have been using room temperature water (20-24°C) for water immersion and the investigators did not notice any drawback of it. In our opinion, it is simpler and cheaper option for water immersion colonoscopy and proof of its efficacy and safety could support the use of water immersion technique in routine practice.
The primary endpoint is cecal intubation time and the investigators suppose that the use of warm water infusion does not shorten it significantly. Patient comfort during colonoscope insertion, water consumption, length of the scope while reaching the cecum, need for external compression, need for positioning of the patient and endoscopist´s difficulty with colonoscopy will be also assessed.
Project description:Bud mutation (bud sport) is mutation occurred in one branch in a tree and the mutant branch shows different phenotype from normal branches. Because bud mutation occurs in a part of plant body, genomic backgrounds of mutant branch and normal branches are the same, except some mutations. Therefore bud mutants are ideal material to identify key genes for important traits of crops. We studied ‘Giant Laf’, a bud mutant setting large fruit, which generated spontaneously in European pear ‘La France’ tree. In ‘Giant Laf’, increase of cell size and DNA reduplication occurred specifically in fruit flesh. The DNA reduplication in ‘Giant Laf’ was observed at 1 week before full bloom stage. This suggested that DNA reduplication observed in ‘Giant Laf’ fruit is not endoreduplication, but endomitosis or nuclear fusion. To identify genes expressed differentially between in ‘Giant Laf’ and in ‘La France’, microarray analysis was performed with RNA from receptacle (fruit flesh) at 1 week before full bloom stage. To isolate the receptacle, laser microdissection was applied. Genes encoding proteins localized in nucleus and cytoskeleton were up-regulated in ‘Giant Laf’. Among these genes, we found several genes which shared homology with previously described DNA reduplication related genes. These are candidates of responsible gene of ‘Giant Laf’ mutation.