Macromineral enrichment of white bread reduces postprandial glycaemia without altering sensory properties: a crossover study.

Background: Metabolism of refined carbohydrates, which are associated with detrimental health effects, is known to be affected by macrominerals including P, Mg and K.

Aims: To assess the impact of their addition to flour on the sensory properties of white pita bread and postprandial glycaemia of healthy individuals.

Methods: The study was conducted at the American University of Beirut (between February and October 2014).

Staphylococcal resistance to streptogramins and related antibiotics.

Streptogramin and related antibiotics are mixtures of two compounds, A and B (e.g. Dalfopristin and Quinupristin), particularly against Gram-positive bacteria.

DNA macroarray for identification and typing of Staphylococcus aureus isolates.

A DNA macroarray containing 465 intragenic amplicons was designed to identify Staphylococcus aureus at the species level and to type S. aureus isolates. The genes selected included those encoding (i) S.

Characteristics of French methicillin-resistant Staphylococcus aureus isolates with decreased susceptibility or resistance to glycopeptides.

According to the French Society of Microbiology, Staphylococcus aureus isolates are suspected to have decreased susceptibility to glycopeptide(s) when at least one colony is able to grow from an inoculum of 10 microL of 2 McFarland bacterial suspension plated on Mueller-Hinton agar containing 5 mg/L teicoplanin and incubated for 48 h at 35-37 degrees C. We analysed 89 methicillin-resistant S. aureus isolates (MRSA), collected in 2000-2001 from 24 hospitals located in 18 French cities, which were able to grow on this selective medium.

Harmonization of pulsed-field gel electrophoresis protocols for epidemiological typing of strains of methicillin-resistant Staphylococcus aureus: a single approach developed by consensus in 10 European laboratories and its application for tracing the spread of related strains.

Pulsed-fieldgel electrophoresis (PFGE) is the most common genotypic method used in reference and clinical laboratories for typing methicillin-resistant Staphylococcus aureus (MRSA). Many different protocols have been developed in laboratories that have extensive experience with the technique and have established national databases. However, the comparabilities of the different European PFGE protocols for MRSA and of the various national MRSA clones themselves had not been addressed until now.

Clonal diversity among streptogramin A-resistant Staphylococcus aureus isolates collected in French hospitals.

We analyzed 62 clinical isolates of streptogramin A-resistant (SGA(r)) Staphylococcus aureus collected between 1981 and 2001 in 14 hospitals located in seven French cities. These isolates, including five with decreased susceptibility to glycopeptides, were distributed into 45 antibiotypes and 38 SmaI genotypes. Each of these genotypes included between 1 and 11 isolates, the SmaI patterns of which differed by no more than three bands.

Cell wall thickening is a common feature of vancomycin resistance in Staphylococcus aureus.

We have previously shown that a thickened cell wall is responsible for the vancomycin resistance of vancomycin-resistant Staphylococcus aureus (VRSA) (equivalent to vancomycin-intermediate S. aureus and glycopeptide-intermediate S. aureus) strain Mu50 (L.

Several regions of the repeat domain of the Staphylococcus caprae autolysin, AtlC, are involved in fibronectin binding.

The autolysin AtlC is the only known fibronectin-binding protein in Staphylococcus caprae strain 96007. The fibronectin-binding domain of AtlC consists of three repeats (AtlCR(1)R(2)R(3)), which are located between the two enzymatic domains. The AtlCR(1)R(2)R(3) domain and the AtlCR(1)R(2) and AtlCR(3) subdomains were expressed separately as His(6)-tagged proteins.

Tn5406, a new staphylococcal transposon conferring resistance to streptogramin a and related compounds including dalfopristin.

We characterized a new transposon, Tn5406 (5,467 bp), in a clinical isolate of Staphylococcus aureus (BM3327). It carries a variant of vgaA, which encodes a putative ABC protein conferring resistance to streptogramin A but not to mixtures of streptogramins A and B. It also carries three putative genes, the products of which exhibit significant similarities (61 to 73% amino acid identity) to the three transposases of the staphylococcal transposon Tn554.

Staphylococcus caprae strains carry determinants known to be involved in pathogenicity: a gene encoding an autolysin-binding fibronectin and the ica operon involved in biofilm formation.

The atlC gene (1,485 bp), encoding an autolysin which binds fibronectin, and the ica operon, involved in biofilm formation, were isolated from the chromosome of an infectious isolate of Staphylococcus caprae and sequenced. AtlC (155 kDa) is similar to the staphylococcal autolysins Atl, AtlE, Aas (48 to 72% amino acid identity) and contains a putative signal peptide of 29 amino acids and two enzymatic centers (N-acetylmuramoyl-L-alanine amidase and endo-beta-N-acetylglucosaminidase) interconnected by three imperfect fibronectin-binding repeats. The glycine-tryptophan (GW) motif found in the central and end part of each repeat may serve for cell surface anchoring of AtlC as they do in Listeria monocytogenes.

Characterization of a variant of vga(A) conferring resistance to streptogramin A and related compounds.

A variant of the vga(A) gene (1,575 bp), encoding an ATP-binding cassette protein conferring resistance to streptogramin A and related antibiotics, was cloned from the chromosome of a Staphylococcus aureus clinical isolate and sequenced. The sequence of the variant was similar to that of the vga(A) gene (83.2% identity).

Screening for Staphylococcus epidermidis markers discriminating between skin-flora strains and those responsible for infections of joint prostheses.

Fifty-four Staphylococcus epidermidis strains responsible for infections of joint prostheses and 23 strains isolated from skin flora were studied for markers of virulence, to discriminate invasive strains from normal flora. They were screened for binding to polystyrene and matrix proteins and for the presence of staphylococcal genes involved in adhesion. The ica operon involved in biofilm formation was the only marker discriminating between these 2 categories of strains.

Retrospective screening for heterogeneous vancomycin resistance in diverse Staphylococcus aureus clones disseminated in French hospitals.

Twenty-five different Staphylococcus aureus strains that are widespread in France were screened by various methods for heterogeneous and low-level resistance to vancomycin. Population analysis on brain-heart infusion agar containing 4 mg/L of the drug detected resistant cells at frequencies of 10-7 to 10-6 in five multiply resistant strains. There was no antagonism between vancomycin and beta-lactam antibiotics.

The value of rRNA gene restriction site polymorphism analysis for delineating taxa in the genus Staphylococcus.

A total of 101 staphylococcal strains were ribotyped using EcoRI and HindIII as restriction enzymes and plasmid pBA2 as the rDNA probe. Isolates from 10 newly described staphylococcal taxa were among those examined. All the ribotypes were added to our database, Staph DB, which now contains the sizes of the bands of 135 EcoRI and 120 HindIII ribotypes from 408 strains belonging to 42 staphylococcal taxa.

Phenotypic and molecular typing of nosocomial methicillin-resistant Staphylococcus aureus strains susceptible to gentamicin isolated in france from 1995 to 1997.

Methicillin-resistant strains susceptible to gentamicin (Gm(s) MRSA) have emerged since 1993 in several French hospitals. To study whether particular clones have spread in various French cities and whether some clones are related to gentamicin-resistant (Gm(r)) MRSA strains, various methods (antibiotyping, phage typing, determination of SmaI macrorestriction patterns before and after hybridization with IS256 transposase and aacA-aphD probes) were used to compare 62 Gm(s) MRSA strains isolated from 1995 to 1997 in nine cities and 15 Gm(r) MRSA strains. Eighteen major SmaI genotypes were identified, of which 11 included only Gm(s) MRSA strains and 5 included only Gm(r) MRSA strains.

satG, conferring resistance to streptogramin A, is widely distributed in Enterococcus faecium strains but not in staphylococci.

A gene almost identical to satG was isolated from an Enterococcus faecium strain. This gene was transferred to a Staphylococcus aureus recipient strain where it conferred resistance to streptogramin A. satG was found to be widely distributed among E.

Comparative analysis of staphylococcal plasmids carrying three streptogramin-resistance genes: vat-vgb-vga.

Several staphylococcal plasmids (26-45 kb) carry all three streptogramin-resistance (Sg(R)) genes, vat, vgb, and vga. Seven such plasmids harbored by independent strains belonging to three taxa (Staphylococcus aureus, S. simulans, and S.

Tracking adhesion factors in Staphylococcus caprae strains responsible for human bone infections following implantation of orthopaedic material.

Ten Staphylococcus caprae strains isolated from four patients and responsible for bone infections following implantation of orthopaedic material were compared to four S. caprae strains collected from milk samples of healthy goats. The following characteristics were investigated: Smal patterns, hybridization patterns with pBA2 (ribotypes), slime production, adhesion to matrix proteins (fibrinogen, fibronectin, collagen) and the staphylococcal adhesion genes (fnbA, clfA, cna, atlE, ica, fbe).

Transposition of IS1181 in the genomes of Staphylococcus and Listeria.

The recombinant plasmid pIP1713 was constructed to analyse the transpositional activity of the insertion sequence IS1181 in Staphylococcus aureus RN4220, Staphylococcus carnosus TM300 and Listeria monocytogenes EGD. This 11.3-kb plasmid contains two genetically different elements: (i) a pE194ts-derived replicon, the ermC gene of which confers resistance to erythromycin in Gram-positive bacteria of several species, and (ii) a copy of IS1181, cloned from S.

Phenotypic and genomic variation among Staphylococcus epidermidis strains infecting joint prostheses.

We studied the SmaI and SstII macrorestriction patterns of 54 Staphylococcus epidermidis strains isolated from 14 patients infected following the implantation of joint prostheses. Multiple strains from pus and infected tissue specimens of each patient were selected on the basis of different colony morphologies and drug resistance patterns. The same criteria were used to select 23 S.

Analysis of two Staphylococcus epidermidis plasmids coding for resistance to streptogramin A.

The two Staphylococcus epidermidis plasmids pIP1629 (7.5 kb) and pIP1630 (14.4 kb) contain the vga gene conferring resistance to streptogramin A.

Characterization of a staphylococcal plasmid related to pUB110 and carrying two novel genes, vatC and vgbB, encoding resistance to streptogramins A and B and similar antibiotics.

We isolated and sequenced a plasmid, named pIP1714 (4,978 bp), which specifies resistance to streptogramins A and B and the mixture of these compounds. pIP1714 was isolated from a Staphylococcus cohnii subsp. cohnii strain found in the environment of a hospital where pristinamycin was extensively used.

Assessment of resolution and intercenter reproducibility of results of genotyping Staphylococcus aureus by pulsed-field gel electrophoresis of SmaI macrorestriction fragments: a multicenter study.

Twenty well-characterized isolates of methicillin-resistant Staphylococcus aureus were used to study the optimal resolution and interlaboratory reproducibility of pulsed-field gel electrophoresis (PFGE) of DNA macrorestriction fragments. Five identical isolates (one PFGE type), 5 isolates that produced related PFGE subtypes, and 10 isolates with unique PFGE patterns were analyzed blindly in 12 different laboratories by in-house protocols. In several laboratories a standardized PFGE protocol with a commercial kit was applied successfully as well.

Characterization of a new staphylococcal gene, vgaB, encoding a putative ABC transporter conferring resistance to streptogramin A and related compounds.

The Staphylococcus aureus plasmid gene, vgaB, conferring resistance to streptogramin (SgA) and related compounds (PIIA, virginiamycin M, mikamycin A, synergistin A, Dalfopristin) was cloned and sequenced. This gene potentially encodes a 552-aa protein, VgaB, of 61,327 Da, which exhibits a significant similarity with the ATP-binding domains of numerous proteins. VgaB has two ATP-binding domains containing each of the A and the B motifs described by Walker et al.

Multiplicity of the genes and plasmids conferring resistance to pristinamycin in staphylococci selected in an Algerian hospital.

In an Algerian hospital where pristinamycin (Pt) was extensively used for the treatment of chronic osteomyelitis and for prophylaxis in bone surgery, the prevalence of pristinamycin-resistant (PtR) staphylococci during a five-month period (20%) was higher than that among staphylococci isolated elsewhere in Algeria (4.5%). Analysis of 13 PtR staphylococci isolated in this hospital revealed a diversity of plasmids and genes conferring resistance to Pt and to related antibiotics.