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141.
142.
Marie-Pierre Forquin Hugo Duvergey Caroline Proux Valentin Loux Jerome Mounier Sophie Landaud Jean-Yves Coppée Jean-Fran?ois Gibrat Pascal Bonnarme Isabelle Martin-Verstraete Tatiana Vallaeys 《Applied and environmental microbiology》2009,75(19):6406-6409
Multilocus sequence typing with nine selected genes is shown to be a promising new tool for accurate identifications of Brevibacteriaceae at the species level. A developed microarray also allows intraspecific diversity investigations of Brevibacterium aurantiacum showing that 13% to 15% of the genes of strain ATCC 9174 were absent or divergent in strain BL2 or ATCC 9175.Brevibacteriaceae play a major part in the cheese smear community (6, 11). The classification and typing of cheese-related Brevibacteriaceae have been based mainly on molecular methods such as amplified ribosomal DNA restriction enzyme analysis, pulsed-field gel electrophoresis, and ribotyping (8, 10, 12). Recently, the original Brevibacterium linens group was split into two species on the basis of their physiological and biochemical characteristics, the sugar and polyol composition of their teichoic acids, and their 16S rRNA sequence and DNA-DNA hybridization levels. One species remains B. linens and is represented by type strain ATCC 9172. The other, represented by type strain ATCC 9175, has been renamed Brevibacterium aurantiacum. Regarding this new classification, the taxonomic position of cheese-related isolates has to be revisited and potential relationships between phylogenetic affiliation and the potential occurrence of given metabolic characteristics redefined (7). The unfinished genome sequence of B. aurantiacum ATCC 9174 has recently been released by the Joint Genome Institute (http://genome.jgi-psf.org/draft_microbes/breli/breli.home.html). The development of focused phylogenetic approaches using multiple markers in conjunction with whole-genome screening techniques such as comparative genomic hybridization (CGH) has proven to be useful for the detailed characterization of pathogenic species, including food pathogens (3, 5, 9). However, only a few technological species have been investigated at an intraspecies level (2). Our intention was thus to develop modern tools to facilitate the typing of strains of technological interest, for which Brevibacteriaceae could be used as a case study. 相似文献
143.
Anne-Laure Brochet Michel Gauthier-Clerc Raphaël Mathevet Arnaud Béchet Jean-Yves Mondain-Monval Alain Tamisier 《Biodiversity and Conservation》2009,18(7):1879-1894
Many wild species, like waterbirds, are exploited for their economic interests. At present, the annual western Palearctic
duck bag is at least 17 million birds. From a sustainable management perspective, wetland users and managers request predictions
of spatial distribution and abundance variations of these bird populations. The objective of this study was to analyze local
factors potentially influencing the diurnal distribution and population size of wintering ducks and coots, the main game species,
in Camargue (southern France). First, we showed that marshland surface area, salinity and hunting disturbance were the principal
variables explaining the duck and coot distribution. Secondly, we tested the hypothesis that hunting disturbance would reduce
the carrying capacity of the Camargue with two analyses: the effect of creating a protected area and the change of the hunting
closing date. This hypothesis was not validated. Our study therefore led us to reconsider the research orientations on the
carrying capacity in this wetland. The surface of protected day roosts seems presently sufficient in the Rhone delta. Consequently,
to increase the population size with the same level of hunting disturbance at the scale of the Camargue, alternative strategies
should be envisaged, such as the creation of nature reserves on nocturnal feeding ground or the creation of large management
units with limited disturbance. 相似文献
144.
Alessio Innocenti Jean-Yves Winum Rebecca A. Hall Fritz A. Mühlschlegel Andrea Scozzafava Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2009,19(10):2642-2645
Inhibition of the β-carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic fungi Cryptococcus neoformans (Can2) and Candida albicans (Nce103) with a series of aromatic, arylalkenyl- and arylalkylboronic acids was investigated. Aromatic, 4-phenylsubstituted- and 2-naphthylboronic acids were the best Can2 inhibitors, with inhibition constants in the range of 8.5–11.5 μM, whereas arylalkenyl and aryalkylboronic acids showed KIs in the range of 428–3040 μM. Nce103 showed a similar inhibition profile, with the 4-phenylsubstituted- and 2-naphthylboronic acids possessing KIs in the range of 7.8–42.3 μM, whereas the arylalkenyl and aryalkylboronic acids were weaker inhibitors (KIs of 412–5210 μM). The host human enzymes CA I and II were also effectively inhibited by these boronic acids. The B(OH)2 moiety is thus a new zinc-binding group for designing effective inhibitors of the α- and β-CAs. 相似文献
145.
146.
Kiem Vu Babette Weksler Ignacio Romero Pierre-Olivier Couraud Angie Gelli 《Eukaryotic cell》2009,8(11):1803-1807
147.
Infection by hepatitis A virus (HAV) can cause acute hepatitis and, rarely, fulminant liver failure, in particular in patients chronically infected with hepatitis C virus. Based on our previous observation that small interfering RNAs (siRNAs) can silence translation and replication of the firefly luciferase-encoding HAV replicon, we now exploited this technology to demonstrate the effect of siRNAs on viral infection in Huh-7 cells. Freshly and persistently infected cells were transfected with siRNAs targeting various sites in the HAV nonstructural genes. Compared to a single application, consecutive siRNA transfections targeting multiple sequences in the viral genome resulted in a more efficient and sustained silencing effect than a single transfection. In most instances, multiple applications of a single siRNA led to the emergence of viral escape mutants with mutated target sites that rendered these genomes resistant to RNA interference (RNAi). Efficient and sustained suppression of the viral infectivity was achieved after consecutive applications of an siRNA targeting a computer-predicted hairpin structure. This siRNA holds promise as a therapeutic tool for severe courses of HAV infection. In addition, the results provide new insight into the structural bases for sequence-specific RNAi. 相似文献
148.
Carine Marinach-Patrice Arnaud Fekkar Ralitsa Atanasova Johanna Gomes Laura Djamdjian Jean-Yves Brossas Isabelle Meyer Pierre Buffet Georges Snounou Annick Datry Christophe Hennequin Jean-Louis Golmard Dominique Mazier 《PloS one》2010,5(1)
Background
Matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI TOF-MS) allows the identification of most bacteria and an increasing number of fungi. The potential for the highest clinical benefit of such methods would be in severe acute infections that require prompt treatment adapted to the infecting species. Our objective was to determine whether yeasts could be identified directly from a positive blood culture, avoiding the 1–3 days subculture step currently required before any therapeutic adjustments can be made.Methodology/Principal Findings
Using human blood spiked with Candida albicans to simulate blood cultures, we optimized protocols to obtain MALDI TOF-MS fingerprints where signals from blood proteins are reduced. Simulated cultures elaborated using a set of 12 strains belonging to 6 different species were then tested. Quantifiable spectral differences in the 5000–7400 Da mass range allowed to discriminate between these species and to build a reference database. The validation of the method and the statistical approach to spectral analysis were conducted using individual simulated blood cultures of 36 additional strains (six for each species). Correct identification of the species of these strains was obtained.Conclusions/Significance
Direct MALDI TOF-MS analysis of aliquots from positive blood cultures allowed rapid and accurate identification of the main Candida species, thus obviating the need for sub-culturing on specific media. Subsequent to this proof-of-principle demonstration, the method can be extended to other clinically relevant yeast species, and applied to an adequate number of clinical samples in order to establish its potential to improve antimicrobial management of patients with fungemia. 相似文献149.
Hector Hernandez-Vargas Marie-Pierre Lambert Florence Le Calvez-Kelm Géraldine Gouysse Sandrine McKay-Chopin Sean V. Tavtigian Jean-Yves Scoazec Zdenko Herceg 《PloS one》2010,5(3)
Background
Hepatocellular carcinoma (HCC) is characterized by late detection and fast progression, and it is believed that epigenetic disruption may be the cause of its molecular and clinicopathological heterogeneity. A better understanding of the global deregulation of methylation states and how they correlate with disease progression will aid in the design of strategies for earlier detection and better therapeutic decisions.Methods and Findings
We characterized the changes in promoter methylation in a series of 30 HCC tumors and their respective surrounding tissue and identified methylation signatures associated with major risk factors and clinical correlates. A wide panel of cancer-related gene promoters was analyzed using Illumina bead array technology, and CpG sites were then selected according to their ability to classify clinicopathological parameters. An independent series of HCC tumors and matched surrounding tissue was used for validation of the signatures. We were able to develop and validate a signature of methylation in HCC. This signature distinguished HCC from surrounding tissue and from other tumor types, and was independent of risk factors. However, aberrant methylation of an independent subset of promoters was associated with tumor progression and etiological risk factors (HBV or HCV infection and alcohol consumption). Interestingly, distinct methylation of an independent panel of gene promoters was strongly correlated with survival after cancer therapy.Conclusion
Our study shows that HCC tumors exhibit specific DNA methylation signatures associated with major risk factors and tumor progression stage, with potential clinical applications in diagnosis and prognosis. 相似文献150.
Haarmann A Deiss A Prochaska J Foerch C Weksler B Romero I Couraud PO Stoll G Rieckmann P Buttmann M 《PloS one》2010,5(10):e13568