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R Quentin

Publications and source records attributed to R Quentin.

At least 19 recordsLinked to original sources
PubMed1995

Genetic diversity of Pseudomonas aeruginosa strains isolated from patients with cystic fibrosis revealed by restriction fragment length polymorphism of the rRNA gene region.

The restriction fragment length polymorphism patterns of rDNAs from Pseudomonas aeruginosa strains isolated from the respiratory tracts of patients suffering from cystic fibrosis were obtained to evaluate the genetic polymorphism of this population of strains. Eighty-seven P. aeruginosa strains isolated from 87 patients from diverse areas of France and the ATCC 10145 strain were examined. Four restriction enzymes were used: BamHI, ClaI, EcoRI, and PstI. Forty-nine strains (56%) were in the three most frequent ribotypes (ribotypes R1 to R3). In addition, hierarchical clustering analysis of the data showed that 71 of the 88 strains (81%) clustered at a distance of less than one-third of the greatest distance observed in the total population. This indicates that clinical isolates implicated in the pathology of cystic fibrosis present a low degree of heterogeneity of rRNA operons, in contrast to the heterogeneity of strains of P. aeruginosa isolated from patients with various other pathologies. This relative homogeneity of rRNA genes was observed independently of the clinical status of the patient and the colony morphology.

Adolescent↗
PubMed1993

Use of nonradioactive DNA probes to identify a Campylobacter jejuni strain causing abortion.

A case of human abortion due to a Campylobacter infection is reported. Cultures revealed two morphologically different isolates with large and small colonies respectively. Using conventional methods of identification, the large colonies were identified as Campylobacter jejuni and the small colonies as Campylobacter coli. Dot blot hybridization and determination of rDNA restriction fragment patterns revealed that both colony types were the same strain of Campylobacter jejuni. This observation illustrates the need to use methods other than phenotypic methods when identifying strains of Campylobacter.

Abortion, Spontaneous↗
PubMed1993

Adherence to human cells of a cryptic Haemophilus genospecies responsible for genital and neonatal infections.

Haemophilus strains usually identified as Haemophilus influenzae biotype IV belonging to a cryptic genospecies are responsible for genital and neonatal infections. As a first approach to identifying the bacterial factors involved in the pathogenesis of these unusual diseases, we studied the piliation, adherence, and invasion properties of 17 strains assigned to this cryptic genospecies. Twelve strains spontaneously displayed abundant peritrichous piliation, and two strains expressed peritrichous pili after enrichment procedures. For virtually all strains, piliation correlated with adhesion to cultured HeLa cells of genital origin and to a lesser extent with adhesion to HEp-2 cells of laryngeal origin. A variation in the adherence properties of the various strains was observed: all piliated strains except one adhered to 50 to 100% of HeLa cells, with a mean number of bacteria per cell varying from 4 to 50. Adherence was not dependent on the state of growth for most strains, was more pronounced with HeLa cells than with HEp-2 cells for 10 of the 12 highly adherent strains, was time and inoculum dependent, and was not followed by significant invasion of cells. Most of the strains belonging to this unusual Haemophilus clone possess adhesins that do not recognize erythrocyte receptors, since agglutination of human erythrocytes was observed with only 3 of the 14 piliated strains.

Bacterial Adhesion↗
PubMed1993

Genetic characterization of a cryptic genospecies of Haemophilus causing urogenital and neonatal infections.

In recent years, reports originating from several areas of the world have identified biotype IV strains of Haemophilus influenzae as a cause of serious urogenital, neonatal, and mother-infant infections. Preliminary analysis of a sample of biotype IV isolates found evidence for a cryptic genospecies of Haemophilus (R. Quentin, A. Goudeau, R. J. Wallace, Jr., A. L. Smith, R. K. Selander, and J. M. Musser. J. Gen. Microbiol. 136:1203-1209, 1990). Eighteen biotype IV strains assigned to the cryptic genospecies were further characterized by their rDNA restriction fragment length polymorphism patterns and genomic DNA-DNA hybridization. Isolates of the cryptic genospecies have distinctive rDNA restriction fragment length polymorphisms that differ from those of Haemophilus haemolyticus and H. influenzae. Genomic hybridization studies show that these organisms are allied with H. influenzae and H. haemolyticus and suggest a distant trifurcation of H. influenzae, H. haemolyticus, and the cryptic genospecies.

Adult↗
PubMed1992

Evaluation of four commercial methods for identification and biotyping of genital and neonatal strains of Haemophilus species.

Four commercial methods for identification of Haemophilus species were evaluated in comparison to conventional methods using 188 genital and neonatal Haemophilus strains. In the case of discrepancies between results obtained by the different methods, DNA-DNA hybridization was performed. The four commercial systems and conventional methods showed excellent correlation of results in 167 strains (88%). DNA-DNA hybridization was performed in 8 strains with discrepant identification results and 13 strains with discrepant biotyping results. In 15 cases discrepancies could be explained by the fact that the strains belonged to a newly recognised species of Haemophilus.

DNA, Bacterial↗
PubMed1992

[Genital herpes].

Explore the source record for details and available documents.

Herpes Genitalis↗
PubMed1992

[Bacterial infection of the newborn by maternal fetal contamination: one can depend on the anamnesis].

All babies born in a University maternity unit over a period of four months had bacteriological swabs taken in the labour ward. This was to see whether a list of criteria in the history for bacterial infection of the newborn could be relied on. The criteria were: premature rupture of the membranes (before labour had started at all), rupture of the membranes for more than 12 hours, stained liquor, prematurity, fetal tachycardia of more than 160 per minute or abnormal rhythm of the heartbeat, an Apgar score of less than 7 after 1 minute, maternal genital or urinary tract infection (not cured) in month before delivery, maternal temperature above 38 degrees C in labour. During the study there were: 570 live births of which 222 (39%) were at risk of infection according to the above list of criteria, 35 had bacterial colonies present and 4 were definitely infected. More cultures from the placenta, the gastric fluid and the skin came back positive when there was a recognised risk of infection. Both the clinical and bacteriological results show that the risk was 5.24 of colonisation when the risk of infection had been recognised. These prospective results when checked against the retrospective results already obtained in the same department, suggest that this kind of screening for infection is worthwhile without being too expensive, and one can rely on the history to screen for neonatal bacterial infection.

Apgar Score↗
PubMed1991

[Newborn bacterial infection caused by materno-fetal contamination. Retrospective epidemiologic study at a maternity unit].

A retrospective epidemiological study of neonatal bacterial infection due to contamination from the mother was carried out in maternity unit. We analysed the results of taking bacterial swabs from the skin and GI tract in newborn children when there was a possibility, or even probability, from the criteria given that there would be infection. These results compare with different criteria. In 19 months there were 2,622 live born children; 40.6% of those had swabs taken; the infection rate was 0.61% of newborns, but 16% of the newborns, had asymptomatic colonisation by bacteria. The high risks of finding positive swabs as shown by increased infection rates by colonisation occurred where the mothers had high temperatures. Our results led us to change the criteria for antibiotic treatment immediately after birth, in newborn babies.

Bacterial Infections↗
PubMed1990

Frequent isolation of capnophilic bacteria in aspirate from Bartholin's gland abscesses and cysts.

Aspirate samples were obtained from 73 patients undergoing surgery for a Bartholin's gland abscess or cyst. Capnophilic bacteria were isolated from 22% of cases, in contrast to previous reports of sporadic isolation. The three Streptococcus pneumoniae isolates were serotype 3 or 4. The eight Haemophilus influenzae isolates could not be serotyped; six of them were biotype II but the electrophoretic band patterns of their outer membrane proteins were heterogeneous, indicating that non-serotypable strains from the same anatomical site may not be related. Four Neisseria gonorrhoeae isolates and one strain of Neisseria subflava were recovered. The role of capnophilic bacteria in the pathogenesis of infections of the Bartholin's gland remains to be clarified.

Abscess↗
PubMed1990

Urogenital, maternal and neonatal isolates of Haemophilus influenzae: identification of unusually virulent serologically non-typable clone families and evidence for a new Haemophilus species.

A collection of 117 strains of Haemophilus influenzae, including 112 non-typable isolates recovered predominantly in the USA and France from genital, obstetric and neonatal sources, was characterized by the electrophoretic mobilities of 10 metabolic enzymes. Eighty-six distinctive multilocus chromosomal genotypes (electrophoretic types, ETs) were distinguished on the basis of allele profiles at the enzyme loci. Isolates of five allied biotype IV ETs were highly divergent from all other strains and hybridization of chromosomal DNA revealed that they undoubtedly represent a previously unrecognized species of Haemophilus. Isolates representing these ETs were recovered predominantly from obstetric infections and serious neonatal diseases and apparently possess specific tropism for the genital tract. Strains of these five ETs were present in samples from both the USA and France, but only in the USA did they cause bacteraemia and meningitis, an occurrence which probably reflects differences in patient management between the two countries. Although strains assigned to H. influenzae (sensu stricto) were strongly polymorphic in multilocus enzyme genotype, 69% of isolates recovered from patients with meningitis and/or septicaemia were assigned to only two clone families, a result suggesting that some serologically nontypable strains of H. influenzae originating from the genital tract are unusually virulent.

Alleles↗