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A L Courtieu

Publications and source records attributed to A L Courtieu.

At least 19 recordsLinked to original sources
PubMed1996

Serotyping of 80 strains from the WHO multicentre international typing study of Listeria monocytogenes.

Serotyping was carried out on 80 coded strains, distribute to all laboratories taking part in the WHO L. monocytogenes multicenter subtyping study. All six laboratories used the method recommended by their coordinator. All 80 strains were typeable. There was complete agreement between the six laboratories on 49 (61.3%) strains (21 serovar 1/2a and 28 serovar 4b strains) which in turn were identical to the expected serovars, known only after decoding. The intralaboratory reproducibility carried out on 11 duplicate strains, ranged from 82 to 100%, with a medium value of 91%. Reproducibility of serotyping L. monocytogenes strains according to serovar varied from 33.3 to 100% for serotypes 3b and 1/2a, respectively, with serovar 4b (x) being incorrectly identified in all six laboratories. Serotyping of L. monocytogenes is easy and simple and is a useful prerequisite for other finer and more discriminatory typing methods. Problems may however, be encountered mainly with the flagellar antigenic factors. There is a need, therefore, for preparing antisera of good quality from which efficient antigenic factors can be obtained.

Humans↗
PubMed1992

Resistance to cefotaxime and seven other beta-lactams in members of the family Enterobacteriaceae: a 3-year survey in France.

During the second quarter each of 1988, 1989, and 1990, a French collaborative study group, including 12 university hospital laboratories, surveyed the resistance to beta-lactams of clinical isolates from hospitalized patients: consecutively, 10,641, 10,692, and 9,382 isolates were tested. The distribution of bacterial species over time was similar in each laboratory. The susceptibilities of microorganisms to amoxicillin, ticarcillin, cephalothin, cefoxitin, cefotaxime (CTX), ceftazidime (CAZ), aztreonam (ATM), and imipenem (IPM) were measured by the disk diffusion method in accordance with the recommendations of the Antibiogram Committee of the French Society for Microbiology. Five reference strains were included for quality control. Extended-spectrum beta-lactamases were detected by the synergistic effect of the combination of clavulanic acid-amoxicillin with CTX, CAZ, and ATM in the double-diffusion test. A synergistic effect with CTX, CAZ, and ATM was detected for 1.5% of all strains, mainly those of Klebsiella pneumoniae (13.3%). For this species, the synergy test enabled the detection of roughly 50% of the resistant strains misclassified as susceptible on the basis of interpretative standards. Extended-spectrum beta-lactamases disseminated in 1990 in most enterobacterial species but at a low frequency. Important variations in the percentages of resistant strains were observed in terms of bacterial species, hospitals, and wards. However, when the total number of strains was considered, the percentages of resistance to newer beta-lactams remained low.

Anti-Bacterial Agents↗
PubMed1991

Latest news on listeriosis.

Emphasis is given essentially to the presentation of recent data in terms of our total knowledge of Listeria and human and animal listeriosis. This disease of extremely varied origin can be studied in terms of two groups of subjects: females in gestation and all other categories of individuals. There was initially only a single species of Listeria, but at least five are known today, only two of which are pathogenic. Their pathogenic power is related essentially to the presence of listerolysin O, although this is not the only factor involved. Identification of Listeria is easy and can be completed with that of its serovar and lysovar. Epidemiological studies have shown that the great majority of listeriosis are anademic. The contamination of receptive subjects is due to certain forms of food. In the absence of efficient vaccination, disease prevention must be obtained by eliminating Listeria from food.

Animals↗
PubMed1991

[In vitro antibacterial activity of a new fluoroquinolone, temafloxacin, against hospital isolates. Results of a multicenter study].

Minimal inhibitory concentrations (MICs) of temafloxacin (TMF) was determined by agar dilution for 2,510 bacterial strains isolated in 1989 in 9 university hospitals. Activity of TMF against nalidixic acid (NAL) susceptible (S) Enterobacteriaceae was close to that of other fluoroquinolones (FQ) (mode MIC: 0.06 micrograms/l); like for other FQ, this activity was reduced against NAL intermediate (mode 1) and resistant (R) (mode 4) Enterobacteriaceae. MICs of TMF against P. aeruginosa were between 0.12 and 128 (mode 0.5-1). TMF had also a good activity against NAL S A. baumannii (mode MIC: 0.06-0.12) but this activity is reduced against NAL R Acinetobacter (mode MIC: 16). TMF was highly active against Haemophilus mode MIC: less than or equal to 0.008), Gonococci (mode MIC: 0.008-0.032), Meningococci (mode MIC: 0.08) and B. catarrhalis (mode MIC: 0.016). TMF showed better activity to other fluoroquinolones against methicillin susceptible Staphylococci (mode MIC: 0.06); the resistant strains (mode MIC: 8) are usually methicillin resistant. Comparatively to the currently available FQ, TMF is so more effective against Enterococci (mode MIC: 1), Streptococci (mode MIC: 0.5-1) and Pneumococci (mode MIC: 0.5). Finally, for the anaerobic bacteria, TMF is more active against C. perfringens (mode MIC: 0.5) than against B. fragilis (mode MIC: 2).

4-Quinolones↗
PubMed1990

Transferable plasmid-mediated antibiotic resistance in Listeria monocytogenes.

A strain of Listeria monocytogenes, isolated from a patient with meningoencephalitis, was resistant to chloramphenicol, erythromycin, streptomycin, and tetracycline. The genes conferring resistance to these antibiotics were carried by a 37-kb plasmid, pIP811, that was self-transferable to other L monocytogenes cells, to enterococci-streptococci, and to Staphylococcus aureus. The efficacy of transfer and the stability of pIP811 were higher in enterococci-streptococci than in the other gram-positive bacteria. As indicated by nucleic acid hybridisation, the genes in pIP811 conferring resistance to chloramphenicol, erythromycin, and streptomycin were closely related to plasmid-borne determinants that are common in enterococci-streptococci. Plasmid pIP811 shared extensive sequence homology with pAM beta 1, the prototype broad host range resistance plasmid in these two groups of gram-positive cocci. These results suggest that emergence of multiple antibiotic resistance in Listeria spp is due to acquisition of a replicon originating in enterococci-streptococci. The dissemination of resistance to other strains of L monocytogenes is likely.

Chloramphenicol Resistance↗
PubMed1990

Detection of respiratory syncytial virus antigen after seventy-two hours of culture.

Between September, 1987, and April, 1989, three techniques for the detection of respiratory syncytial virus (RSV) were compared: indirect immunofluorescence (IF) on the sample, indirect immunofluorescence after 72 h of MRC-5 cell culture (IF 72h), and detection of the cytopathic effect (CPE) by MRC-5 and HEp-2 cell culture. A study of 383 nasal aspirates from young children admitted to the Centre Hospitalier de Nantes (CHR) showing miscellaneous respiratory symptoms produced the following results: 143 samples (37%) were RSV positive by IF, 119 (31%) were positive by IF 72h, and 117 (31%) showed RSV-induced CPE. In comparison with tissue culture isolation (TC), the sensitivities of IF and IF 72h were 89% and 80% and their specificities 85% and 91%, respectively. During the winter of 1988-1989, of the 110 RSV-positive nasal aspirates (104 by IF, 89 by IF 72h, 83 by CPE detection), 109 were identified by IF and/or IF 72h. IF 72h affords rapid detection of RSV.

Antigens, Viral↗
PubMed1989

Isolation of Listeria from French meat products.

One hundred and ten Listeria strains were recovered from 378 meat samples: L. monocytogenes (68 strains), L. innocua (45) and L. welshimeri (7). L. monocytogenes isolates mainly belonged to serogroup 1/2 (1/2: 23 strains; 1/2b: 1; 1/2c: 43; 4b: 1). These results contrast those observed for 355 human strains isolated during the same period in France where serovar 4b strains were largely predominant (66.5%). 45% of the strains were phage typable. These results underline the widespread occurrence of Listeria in meat products.

Animals↗
PubMed1989

An epidemiological survey of human listeriosis in France during 1987, using serotyping and phage typing.

During 1987 the French National Reference Center for Listeria received, from this country, 384 Listeria monocytogenes strains isolated from human listeriosis cases. A constant exchange of information and strains between the Reference Center and the Bacterial Ecology Unit of the Institute Pasteur of Paris allowed complete characterization of these isolates, using serotyping and phage typing. Among the strains studied 22%, 13% and 63%, respectively belonged to serovars 1/2a, 1/2b, and 4b, but this distribution can vary according to place, and time of isolation. Only 58% of strains were phage-typeable (1/2a: 29%), (1/2b: 66%) and (4b: 40%). Phage typing allows to consider that French human cases, in 1987, were mainly sporadic. However, a small number of cases corresponding to similar phage types could be clustered according to place and/or time.

Bacteriophage Typing↗
PubMed1989

[Determination of the sensitivity of bacteria to antibiotics by an agar diffusion method and use of the API ATB system: a comparative study].

130 bacterial strains were studied for their antibiotics sensitivity by an agar diffusion method and using API ATB System: 50 Enterobacteriaceae, 12 other Gram negative bacilli, 48 Staphylococci and 20 Streptococci. The results concurred in 83 p. cent of the cases. Discrepancies were essentially observed for coagulase negative Staphylococci and Streptococci. Strains appeared more resistant by API ATB System than by the agar diffusion method. Discrepancies mostly concerned beta-lactam antibiotic sensitivity for Gram negative bacilli or aminoglycosides and macrolides sensitivity for Staphylococci. They also concerned sulfamides and trimethoprim sensitivity for all bacterial species.

Colony Count, Microbial↗
PubMed1989

Pharmacokinetics of fosfomycin in normal and burn patients. Effect of probenecid.

The pharmacokinetics of fosfomycin are modified in burn patients, suggesting a net tubular secretion in such patients. In an attempt to verify this hypothesis, five healthy normal volunteers were studied The pharmacokinetics of fosfomycin were studied with and without probenecid. In the absence of probenecid, the renal clearance of the drug was equal to that of creatinine. With probenecid, the renal clearance of fosfomycin decreased, whereas creatinine clearance did not. This result suggests the existence of a tubular secretion, which might be enhanced in burn patients.

Adult↗
PubMed1988

[Immunologic response in herpes encephalitis: development of the antibody serum/cerebrospinal fluid ratio in 13 cases].

Serological monitoring was performed in 13 cases of herpetic encephalitis (one infant and 12 adults). Samples taken simultaneously from blood and cerebrospinal fluid (CSF) were tested before and after initiation of antiviral treatment. Antiherpesvirus (anti-HSV) antibodies were assayed by an ELISA method. The state of the blood-brain barrier was controlled by assaying other antiviral antibodies. Immune response was studied during the 3-to-4 weeks of the course of the infection. Anti-HSV IgG levels in CSF increased markedly after 12 days. At the same time, antibody serum/CSF ratios dropped below a value of 20, indicating intrathecal secretion of the antibody. Based on results in monitoring these 13 cases, it may be suggested that 3 samples of serum and CSF are required to confirm the herpetic etiology, including 2 samples taken during the second week of the course of encephalitis.

Adult↗
PubMed1988

[Comparison of 2 immunoenzyme methods for the determination of anti-cytomegalovirus IgM].

An antibody capture assay technique using a labeled antigen (Wellcome Laboratories) and an ELISA technique performed after elimination of serum IgG (Behring Laboratories) were assessed for determination of anti-cytomegalovirus IgM. Their specificity and sensitivity were compared in tests on 208 sera, some (60) of which had IgM rheumatoid factor, antinuclear antibodies or anti-Epstein-Barr virus antibodies. The other sera were analyzed relative to diagnosis of a cytomegalovirus infection. The antibody capture assay technique was slightly more sensitive than the ELISA technique but did not resolve all the specificity problems.

Antibodies, Antinuclear↗
PubMed1988

[Bacterial contamination of the inspiratory circuit of artificial ventilation apparatus: influence of the frequency of circuit renewal and the duration of ventilation].

In a study concerning contamination of artificial ventilators (Drager model UV1), the influence of 2 parameters was assessed: the frequency of changing the circuit (2 and 4 days) and the interval between admission of the patient into the intensive care unit and obtaining the sample. As a function of these variables, 4 groups of 15 patients each were constituted. The levels of contamination noted at 4 sites in the inspiratory phase tubing (cascade humidifier, condensate collector, tubing nearest to the patient and tubing nearest to the humidifier) and in the gas flow showed no significant difference between the groups, regardless of whether the circuit was changed after 2 or 4 days, or whether the patient had been recently admitted to the department or had been there for at least 6 days. Quantitative and qualitative study of bacteria showed that the one(s) contaminating the inspiratory phase tubing were the same as the one(s) colonizing the tracheal secretions of the patient, and that the most contaminated areas were those nearest to the patient (proximal tubing, collector), which confirms the retrograde contamination of the circuit.

Bacterial Infections↗