Identification of new phages to type Staphylococcus aureus strains and comparison with a genotypic method.

The aim of this study was to optimize the epidemiological monitoring of strains of Staphylococcus aureus, a major cause of hospital-acquired infections. From September to December 1998 47 S. aureus strains isolated from swabs taken from orthopaedic and trauma patients were in studied.

Combined ribotyping and random multiprimer DNA analysis to probe the population structure of Listeria monocytogenes.

To improve our understanding of the genetic links between strains originating from food and strains responsible for human diseases, we studied the genetic diversity and population structure of 130 epidemiologically unrelated Listeria monocytogenes strains. Strains were isolated from different sources and ecosystems in which the bacterium is commonly found. We used rRNA gene restriction fragment length polymorphism analysis with two endonucleases and random multiprimer DNA analysis with seven oligonucleotide primers to study multiple genetic features of each strain.

Multivariate analysis of determinants of bacterial contamination of whole-blood donations.

Background And Objectives: Introduction of bacteria into blood components at the collection stage seems to be a frequent occurrence. We therefore assessed determinants of bacterial contamination of whole-blood donations to gain insight into contamination mechanisms and direct prevention.

Materials And Methods: A cross-sectional study was carried out on donors accepted for whole-blood donation in four French blood banks.

Efficacy of a new collection procedure for preventing bacterial contamination of whole-blood donations.

Background: Transfusion-related bacterial contamination is a serious problem. The introduction of bacteria into donations at the collection stage seems frequent, despite well-conducted phlebotomy site preparation. Additional preventive measures are required.

Low sensitivity of Listeria monocytogenes to quaternary ammonium compounds.

Ninety-seven epidemiologically unrelated strains of Listeria monocytogenes were investigated for their sensitivities to quaternary ammonium compounds (benzalkonium chloride and cetrimide). The MICs for seven serogroup 1/2 strains were high. Three came from the environment and four came from food; none were isolated from human or animal samples.

Pseudomonas aeruginosa from cystic fibrosis patients: study using whole cell RAPD and antibiotic susceptibility.

Pseudomonas aeruginosa is the most important bacterial pathogen in lung disease of cystic fibrosis patients. Different morphotypes of the bacterium are frequently recovered in sputum samples of these patients. We developed a whole cell Randomly Amplified Polymorphic DNA (RAPD) technique in order to establish the relatedness between morphotype, genotype and antibiotic susceptibility.

Evaluation of seven experimental phages for inclusion in the international phage set for the epidemiological typing of Listeria monocytogenes.

The purpose of our study was to evaluate the inclusion of seven experimental phages into the international phage set for subtyping Listeria monocytogenes. The seven additional phages included the broad-host-range virulent Myoviridae phage A511 (M. J.

The WHO multicenter study on Listeria monocytogenes subtyping: random amplification of polymorphic DNA (RAPD).

As part of a WHO multicenter study on Listeria monocytogenes subtyping methods the random amplification of polymorphic DNA (RAPD)-technique was evaluated. Six participants were asked to use a standard protocol to analyse a set of 80 L. monocytogenes strains.

WHO study on subtyping Listeria monocytogenes: results of phage-typing.

A multi-centered study on phage typing of Listeria monocytogenes was carried out using 80 cultures sent under code and tested in six different laboratories. Phage typing was performed using an international phage set in five laboratories and phage sets unique to two laboratories. Testing of cultures sent in duplicate showed similar levels of reproducibility to that previously reported.

[Informative capacity of 8 serological tests in the diagnosis of human brucellosis].

Assessment of the informative value of 8 immunological tests: sero-agglutination (Wright and Rose Bengale), indirect immunosorbent assay, counter immuno electrophoresis, ELISA IgG, IgM and IgA, and particle counting immunoassay (PACIA) has been performed among the results of serum of 209 patients. The patients were divided in four groups: 71 who already had brucellosis, 18 Yersinia infections, 12 Tularemia and 108 free of desease. The informative capacities of a positive result of counter immuno electrophoresis (Protein antigen Brucellin-INRA Tours-Nouzilly) is higher than others reactions and can be proposed as a confirmatory test of brucellosis.

Typing of Staphylococcus epidermidis strains by random amplification of polymorphic DNA.

The polymerase chain reaction was used to obtain randomly amplified polymorphic DNA profiles for typing of Staphylococcus epidermidis strains. Epidemiologically unrelated S. epidermidis isolates were screened with randomly amplified polymorphic DNA analysis.

Epidemiological analysis of Acinetobacter baumannii strains isolated from a surgical intensive care unit.

A serious epidemic of Acinetobacter baumannii resistant to imipenem occurred in the surgical intensive care unit of the hospital Charles-Nicolle in Tunis during February 1994, causing two deaths among three patients. The Acinetobacter strains were isolated from various samples of the intensive care unit. The techniques used for typing were biotyping, antibiogram, plasmid profiles and chromosomal DNA by random amplified polymorphic DNA (RAPD).

Proposals for optimization of the international phage typing system for Listeria monocytogenes: combined analysis of phage lytic spectrum and variability of typing results.

Combined analysis of 5,179 serial phage reactions of 20 Listeria monocytogenes propagating strains over 14 years and phage typing results from 2,659 further L. monocytogenes strains allowed us to estimate lytic spectrum specificity and the variability of the lytic reactions of 35 phages. These included the 26 phages recommended for the international method for phage typing defined in 1985 by Rocourt et al.

Changes in microbial ecology and use of cloxacillin.

There is generally a positive correlation between antibiotic consumption and incidence of resistance to antibiotics used either for prophylaxis or therapy in human infections. This was not the case for two surgical wards in our hospital. A 15-year study showed that the incidence of methicillin-resistant Staphylococcus aureus (MRSA) was unrelated to cloxacillin consumption, and in fact fell after introduction into the two wards of an antibiotic policy based on cloxacillin.

Plasmid-borne cadmium resistance genes in Listeria monocytogenes are present on Tn5422, a novel transposon closely related to Tn917.

The complete (6,449-bp) nucleotide sequence of the first-described natural transposon of Listeria monocytogenes, designated Tn5422, was determined. Tn5422 is a transposon of the Tn3 family delineated by imperfect inverted repeats (IRs) of 40 bp. It contains two genes which confer cadmium resistance (M.

Plasmid-borne cadmium resistance genes in Listeria monocytogenes are similar to cadA and cadC of Staphylococcus aureus and are induced by cadmium.

pLm74 is the smallest known plasmid in Listeria monocytogenes. It confers resistance to the toxic divalent cation cadmium. It contains a 3.

[Brucellosis among occupationally exposed people: evaluation of immunological tests after vaccination].

For the evaluation of immunological tests during an epidemiological survey and of vaccination with the PI brucellin vaccine, in an occupationally exposed environment, a sample group of 354 subjects was studied. The vaccinal strategy was based on the outcome of a skin test for hypersensitivity: the PS brucellin test. In this framework, the serological status and evolution of individuals with positive or negative reactions to this test were analysed.

[Brucella vaccination in professionally exposed subjects. Prospective study].

This prospective phase IV study on cohort concerns a vaccine made of the phenol-insoluble fraction of Brucella abortus biotype 1 (B19 strain). Three hundred and three professionally exposed subjects entered the study; 161 out of 182 subjects (88.5 percent) with negative response to an intradermal test for detection of previous contamination accepted to be vaccinated.

Plasmids in Listeria monocytogenes in relation to cadmium resistance.

One hundred and seventy-three unrelated Listeria monocytogenes strains isolated from humans, animals, the environment, and food were analyzed for the presence of plasmids. Extrachromosomal DNA was found in 28% of the strains. Plasmid DNA was extracted more frequently from L.

A comparative study of randomly amplified polymorphic DNA analysis and conventional phage typing for epidemiological studies of Listeria monocytogenes isolates.

The analysis of RAPD profiles generated by PCR with a single 10-mer, HLWL74, was compared to bacteriophage susceptibility data for epidemiological typing of Listeria monocytogenes strains. A total of 104 L. monocytogenes strains was screened, all from serogroup 1 or serotype 4b.

[Post-antibiotic diarrheas: role of Klebsiella oxytoca].

From May 1989 to January 1991, 20 patients were investigated for antibiotic-associated acute diarrhea. Colonoscopy or rectosigmoidoscopy was performed in each patient. Cultures of colonic mucosal biopsies were carried out using conventional culture grounds (cystine-lactose-electrolyte-deficient).

DNA polymorphism in strains of Listeria monocytogenes.

DNA polymorphism in 35 Listeria monocytogenes strains belonging to serovars 1/2a, 1/2b, 1/2c, and 4b was studied by genomic DNA digestion. The restriction endonucleases ApaI and NotI, which cleave DNA at rare sequences, were used, and DNA fragments were analyzed by pulsed-field gel electrophoresis. Restriction fragment length polymorphism varied among different serovars and was used for epidemiological studies, but serovar 1/2c isolates could not be analyzed because their restriction patterns were indistinguishable.

Treatment failure and recurrent human listeriosis.

We review 12 patients and report an additional two new patients, each of whom had two episodes of listeriosis. In seven patients the two episodes were due to the same strain of Listeria monocytogenes, and we speculate that this was a reactivation of the original infection. In one patient, isolates of L.