Proteomic analysis of Staphylococcus aureus biofilms grown in vitro on mechanical heart valve leaflets.

The in vitro colonization of three commercial heart valve leaflets by Staphylococcus aureus was investigated. The leaflets, made of pyrolytic carbon alloyed with or without silicon, displayed similar surface properties (wettability, roughness) and were readily colonized by S. aureus that formed patchy biofilms on the three supports.

Biofilm formation on pyrolytic carbon heart valves: influence of surface free energy, roughness, and bacterial species.

Objective: The aim of this study was to analyze the interaction of surface free energy and roughness characteristics of different pyrolytic carbon heart valves with three bacterial species on biofilm formation.

Methods: Three pyrolytic carbon heart valves (St Jude Medical [St Jude Medical Inc, Minneapolis, Minn], Sulzer Carbomedics [CarboMedics Inc, Austin, Tex], and MedicalCV [Medical Incorporated, Inver Grove Heights, Minn]) were tested. Roughness was measured by interferential microscopy and surface free energy by contact angle technique.

Effects of glutamine supplementation on gut barrier, glutathione content and acute phase response in malnourished rats during inflammatory shock.

Aim: To evaluate the effect of glutamine on intestinal mucosa integrity, glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock.

Methods: Plasma acute phase proteins (APP), jejunal APP mRNA levels, liver and jejunal glutathione concentrations were measured before and one, three and seven days after turpentine injection in 4 groups of control, protein-restricted, protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed.

Detection of Neisseria meningitidis DNA from skin lesion biopsy using real-time PCR: usefulness in the aetiological diagnosis of purpura fulminans.

Objective: The present study evaluated the usefulness of a real-time polymerase chain reaction (rtPCR) assay for the detection of Neisseria meningitidis (Nm) and genogrouping on skin lesion biopsies in patients with purpura fulminans (PF).

Design: Retrospective single-centre study.

Setting: Adult and paediatric intensive care units at the University Hospital of Rouen.

Tolerance to the glycopeptides vancomycin and teicoplanin in coagulase-negative staphylococci.

Tolerance to vancomycin and teicoplanin in 90 clinical isolates of coagulase-negative staphylococci (CoNS) was investigated by time-kill curve methodology. Only six strains, belonging to the Staphylococcus lugdunensis species, exhibited tolerance. The seven other S.

Multilocus sequence analysis and comparative evolution of virulence-associated genes and housekeeping genes of Clostridium difficile.

A multilocus sequence analysis of ten virulence-associated genes was performed to study the genetic relationships between 29 Clostridium difficile isolates of various origins, hosts and clinical presentations, and selected from the main lineages previously defined by multilocus sequence typing (MLST) of housekeeping genes. Colonization-factor-encoding genes (cwp66, cwp84, fbp68, fliC, fliD, groEL and slpA), toxin A and B genes (tcdA and tcdB), and the toxin A and B positive regulator gene (tcdD) were investigated. Binary toxin genes (cdtA and cdtB) were also detected, and internal fragments were sequenced for positive isolates.

[Choice of a strategy for screening for methicillin-resistant Staphylococcus aureus on admission to rehabilitation units].

Objective: To identify a strategy of MRSA screening (methicillin-resistant Staphylococcus aureus) on admission to geriatric rehabilitation units, which would lead to acceptable efficacy and cost compared with a reference maximaliste strategy combining all six sampling sites. Method MRSA screening was conducted prospectively for 3 months in all the patients admitted to a geriatric follow-up and rehabilitation unit, using samples from the nostrils, armpits, urine scars cutaneous ulcers and sores. Six strategies were defined combing different sampling sites.

Multiplex PCR targeting tpi (triose phosphate isomerase), tcdA (Toxin A), and tcdB (Toxin B) genes for toxigenic culture of Clostridium difficile.

A multiplex PCR toxigenic culture approach was designed for simultaneous identification and toxigenic type characterization of Clostridium difficile isolates. Three pairs of primers were designed for the amplification of (i) a species-specific internal fragment of the tpi (triose phosphate isomerase) gene, (ii) an internal fragment of the tcdB (toxin B) gene, and (iii) an internal fragment of the tcdA (toxin A) gene allowing distinction between toxin A-positive, toxin B-positive (A+B+) strains and toxin A-negative, toxin B-positive (A-B+) variant strains. The reliability of the multiplex PCR was established by using a panel of 72 C.

Multilocus sequence typing analysis of human and animal Clostridium difficile isolates of various toxigenic types.

A multilocus sequence typing (MLST) scheme was developed to study the genetic relationships and population structure of 72 Clostridium difficile isolates from various hosts, geographic sources, PCR ribotypes, and toxigenic types (determined by PCR targeting tcdA and tcdB genes). MLST was performed by DNA sequence analysis of seven housekeeping genes (aroE, ddl, dutA, tpi, recA, gmk, and sodA). The number of alleles ranged from five (dutA and ddl) to eleven (recA).

Comparative in vitro and in vivo study of nine alcohol-based handrubs.

Background: Hygienic hand disinfection using alcohol-based handrubs (AHRs) is an alternative method to conventional handwashing in hospital wards. Because a documented choice of such products would consider data from in-care evaluation, we designed a comparative study of 9 AHRs both in vitro and in vivo in actual care conditions.

Methods: The bactericidal activity of AHRs was first measured in vitro against 4 hospital strains exhibiting multiple antibiotic resistance: Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, and Enterobacter aerogenes.

Genotypic differentiation of twelve Clostridium species by polymorphism analysis of the triosephosphate isomerase (tpi) gene.

Housekeeping genes encoding metabolic enzymes may provide alternative markers to 16S ribosomal DNA (rDNA) for genotypic and phylogenetic characterization of bacterial species. We have developed a PCR-restriction fragment length polymorphism (PCR-RFLP) assay, targeting the triosephosphate isomerase (tpi) gene, which allows the differentiation of twelve pathogenic Clostridium species. Degenerate primers constructed from alignments of tpi sequences of various gram-positive bacteria allowed the amplification of a 501 bp target region in the twelve Clostridium type strains.

Nosocomial urinary tract infections in urologic patients: assessment of a prospective surveillance program including 10,000 patients.

Objective: Hospital-acquired urinary tract infections (HUTI) represent a significant impairment in the quality of health care. Incidence in catheterized patients has been estimated at approximately 20%, however few data are available in urologic patients. We report a prospective surveillance program over 6 years in our urologic department and evaluate its evolution.

Septicemia due to Pasteurella pneumotropica: 16S rRNA sequencing for diagnosis confirmation.

Bacteremia due to Pasteurella pneumotropica occurs infrequently. We report a case of septicemia in a 72-year-old woman who had no underlying illness. The microorganism was isolated from 10 blood cultures and identified by conventional and molecular methods.