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R Giroux

Publications and source records attributed to R Giroux.

10 recordsLinked to original sources
PubMed2005

Characterization of a Tn5382-like transposon containing the vanB2 gene cluster in a Clostridium strain isolated from human faeces.

OBJECTIVES: During a hospital surveillance programme to detect VRE carriers, an anaerobic vancomycin-resistant bacterial strain CCRI-9842 containing a vanB gene was isolated from a human faecal specimen. In this study, we have characterized this strain and its vanB-containing element. METHODS: Strain CCRI-9842 was characterized by 16S rDNA sequencing and susceptibility testing. PCR mapping and sequencing of the vanB-containing element, as well as plasmid extraction and mating experiments, were carried out to investigate the genetic basis of vancomycin resistance in this strain. RESULTS: Strain CCRI-9842 was identified as a Clostridium species closely related to Clostridium bolteae (96.8% 16S rDNA identity). This strain was resistant to a high level of vancomycin (MIC of 256 mg/L), but was susceptible to teicoplanin and ampicillin. The complete sequence of the CCRI-9842 vanB gene exhibited 99.1% identity with that of vanB2. PCR mapping and sequencing showed that the genetic element carrying vanB2 was similar to transposon Tn5382/Tn1549. This Tn5382-like transposon forms circular intermediates and is flanked on the left and right ends by repeat sequences of at least 700 bp in the opposite direction. No plasmid was detected in this strain, suggesting that the Tn5382-like transposon was integrated into the chromosome. The vancomycin resistance was not transferable to enterococci. CONCLUSIONS: Our report shows for the first time the presence of a Tn5382-like transposon carrying vanB2 in a Clostridium species of the human intestinal flora. This suggests that the vanB2 Tn5382-like transposon is an important vector for the spread of vancomycin resistance in several bacterial species.

Bacterial Proteins↗
PubMed2005

High prevalence of glycopeptide resistance genes vanB, vanD, and vanG not associated with enterococci in human fecal flora.

The presence of Enterococcus-associated vancomycin resistance genes vanA, vanB, vanD, vanE, and vanG in rectal swabs was investigated in two hospitals using PCR. All vanA genes detected were associated with vancomycin-resistant enterococci (VRE), whereas VRE-associated vanB genes were detected in only one hospital (4.7%). However, in both hospitals, high prevalences of vanB (6.2 and 2.3%), vanD (43.8 and 26.7%), and vanG (10.5 and 6.9%) genes not associated with enterococci were found.

Bacterial Proteins↗
PubMed2004

New real-time PCR assay for rapid detection of methicillin-resistant Staphylococcus aureus directly from specimens containing a mixture of staphylococci.

Molecular methods for the rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) are generally based on the detection of an S. aureus-specific gene target and the mecA gene. However, such methods cannot be applied for the direct detection of MRSA from nonsterile specimens such as nasal samples without the previous isolation, capture, or enrichment of MRSA because these samples often contain both coagulase-negative staphylococci (CoNS) and S. aureus, either of which can carry mecA. In this study, we describe a real-time multiplex PCR assay which allows the detection of MRSA directly from clinical specimens containing a mixture of staphylococci in <1 h. Five primers specific to the different staphylococcal cassette chromosome mec (SCCmec) right extremity sequences, including three new sequences, were used in combination with a primer and three molecular beacon probes specific to the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. Of the 1,657 MRSA isolates tested, 1,636 (98.7%) were detected with the PCR assay, whereas 26 of 569 (4.6%) methicillin-susceptible S. aureus (MSSA) strains were misidentified as MRSA. None of the 62 nonstaphylococcal bacterial species or the 212 methicillin-resistant or 74 methicillin-susceptible CoNS strains (MRCoNS and MSCoNS, respectively) were detected by the assay. The amplification of MRSA was not inhibited in the presence of high copy numbers of MSSA, MRCoNS, or MSCoNS. The analytical sensitivity of the PCR assay, as evaluated with MRSA-negative nasal specimens containing a mixture of MSSA, MRCoNS, and MSCoNS spiked with MRSA, was approximately 25 CFU per nasal sample. This real-time PCR assay represents a rapid and powerful method which can be used for the detection of MRSA directly from specimens containing a mixture of staphylococci.

Bacterial Proteins↗
PubMed2000

[Myocardial infarction with normal or near normal coronary arteries: late outcome of seven patients].

Myocardial infarction with normal or near normal coronary arteries: Late outcome of seven patients Myocardial infarction with normal or near normal coronary arteries probably results from thrombotic occlusion that is followed by lysis and recanalization; in about a third of affected patients, coronary spasm appears to be the trigger. The clinical profile of this syndrome is well known: patients are young and without coronary risk factors except cigarette smoking, and they have no angina before or after their infarction. However, the late prognosis remains controversial. Between December 1976 and April 1984, myocardial infarction with normal or near normal coronary arteries was diagnosed in seven patients who were subsequently followed for a mean of 19 years. Observations during this follow-up show that the majority of patients experienced one or more recurrences that, in three cases, initiated the development of a severe ischemic cardiomyopathy.

Adult↗
PubMed1991

Nongaussian distribution curve of heterophorias among children.

The purpose of this study was to measure the distribution curve of horizontal and vertical phorias among children. Kolmogorov-Smirnov goodness of fit tests showed that these distribution curves were not Gaussian among (N = 2048) 6- to 13-year-old children. The distribution curve of horizontal phoria at far and of vertical phorias at far and at near were leptokurtic; the distribution curve of horizontal phoria at near was platykurtic. No variation of the distribution curve of heterophorias with age was observed. Comparisons of any individual findings with the general distribution curve should take the nonGaussian distribution curve of heterophorias into account.

Adolescent↗
PubMed1988

Reliability and validity of the dot visual acuity test.

The reliability of the dot visual acuity test (DVAT) was demonstrated using the test-retest method. The test, however, was not found to be valid when comparing it with the Sjögren test. Since the DVAT has previously been shown to be valid when compared to the Tumble E test, these results bring into question the validity of the Sjögren test when compared to the Tumble E test.

Child↗
PubMedDate not supplied

[Recurrent infarction without coronary atheromatosis].

Acute myocardial infarction without obstructive atherosclerosis is a well known entity characterized by the young age of the patients, the low incidence of risk factors and the absence of pre- and post infarction angina. The myocardial necrosis is probably caused by a thrombotic phenomenon perhaps initiated and/or exacerbated by a coronary spasm. It is generally thought that recurrence is rare and long term prognosis relatively benign but this may be a misconception. Three cases are reported of patients who had a second myocardial infarction, transmural infarction in each case, 17 to 36 months after the initial event. Prophylactic treatment after the second accident seems undoubtedly indicated. Until large randomized trials have established the best treatment, it appears logical to prescribe antithrombotic drugs (antiplatelet or anticoagulant drugs) with, perhaps, coronary spasmolytic drugs like calcium antagonists.

Adult↗