Search PubMed⌕ Search

Biomedical subjects

G Aubert

Publications and source records attributed to G Aubert.

At least 91 records · Page 5Linked to original sources
PubMed1993

[Survey with three epidemiological markers after 22 cases of diarrhea caused by Clostridium difficile in a geriatric hospital].

In a geriatric hospital of Saint-Etienne (Charité), among 153 patients having presented a nosocomial diarrhea from September 1990 to August 1991 Clostridium difficile (C.d.) has been isolated in 22 cases. Two of the nine units of the hospital had the highest incidence rates: 4.6 and 3.7%. In the faeces of 16 patients, C.d. was toxinogenic. In all cases, except one, antibiotic preceded diarrhea. Amoxicillin + clavulanic acid treatment was the most frequently responsible (65%). For detecting an eventual outbreak, several epidemiologic markers were evaluated: Clindamycin MIC, protein profiles, serotyping. Clindamycin susceptibility differentiated two Cd. types, but has no epidemiologic value. Protein profiles, performed by SDS-Page, individualized 6 different profiles, but 10 strains gave no classifiable profiles. Serotyping, applied by M. Delmée, appeared as the most interesting marker. Inquiry allowed to eliminate an outbreak but revealed two episodes of cross contaminations in the 3 units, 2 of them having the highest incidence rates. Markers proved persistence of the same C.d. strain in some patients who were correctly treated by metronidazole.

Aged↗
PubMed1993

[Evaluation of three automated blood culture systems. Bio Argod, Bact T/Alert, bactec NR-860].

In 1991 and 1992, three automated blood culturing systems were successively assessed ("Diagnostics Pasteur" Bio Argos: 1,120 Vials, "Organon Teknika" BacT/Alert: 1,400 vials and "Becton Dickinson" bactec NR-860: 2,146 standard vials 6 and 7 and 2,360 resin vials 26 and 27), and compared with the conventional system (C) (Roche aerobic BHI-S Liquoîd, and Diagnostics Pasteur anaerobic prereduced Shaedler). Duplicate blood cultures were collected in various hospital services. They were processed over a 7-day period by the automated instruments and were incubated for 10 days using conventional techniques. The percentage of positivity (clinically significant results) obtained with the automated instruments was similar to that obtained with conventional techniques. Bio Argos: 3.4 p. cent vs 3.8 p. cent with C, BacT/Alert: 3.9 p. cent vs 3.5 p. cent, Bactec standard 6 and 7 vials: 5.6 p. cent vs 6.4 p. cent, and resin 26 and 27: 4.2 p. cent vs 3.1 p. cent. A better sensitivity was found with Bactec resin 26 and 27 vials when compared to C for Staphylococcus aureus (22 p. cent of S. aureus strains were isolated only with resin vials 26 and 27). False positives were as follow: 0.36 p. cent for BacT/Alert, 2.1 p. cent for Bio Argos and 3.5 p. cent for Bactec. The fastest detection rate was observed with the instrument which shakes the vials continuously (BacT/Alert): 73.6 p. cent of positive vials were detected on the day the vials were received at the laboratory. Ninety-four percent of the Bactec resin 26 and 27 positive vials, 90.6 p. cent of the BacT/Alert positive vials, 84 p. cent of the Bactec 6 and 7 positive vials and 73.7 p. cent of the Bio Argos positive vials were detected within twenty-four hours.

Bacteria, Aerobic↗
PubMed1992

[The role of the bacteriological laboratory in the criteria for choosing and monitoring antibiotic treatment].

The constant development of clinical bacteriology and the consequence this has on the way an infected patient is approached and treated require that be examined a bacteriology laboratory's contribution in choosing and monitoring an antibiotic treatment. In the economic context of hospitals, one of the aims is to rationalize the prescription of biological investigations, as well as that of antibiotic treatments. The patient's history, his clinical state as well as the place where he has been admitted must be taken into account to establish, together with microbiologists, a hierarchy of the biological investigations required and to adapt the antibiotic treatment. In the laboratory, both the bacteriostatic and bactericidal sensitivity to antibiotics may be assessed in vitro. The best therapeutic antibiotic concentrations may be obtained by monitoring the pharmacokinetics of antibiotics.

Anti-Bacterial Agents↗
PubMed1992

Emergence of quinolone-imipenem cross-resistance in Pseudomonas aeruginosa after fluoroquinolone therapy.

Emergence of resistance to fluoroquinolones was observed in two clinical isolates of Pseudomonas aeruginosa after ciprofloxacin or norfloxacin monotherapy. In the first case, the resistant variants exhibited quinolone-imipenem cross-resistance (MIC of norfloxacin and ciprofloxacin: 16 mg/L; MIC of imipenem: 8 mg/L), although the patient had never received imipenem treatment, while the strain from the second case remained imipenem-susceptible (MIC of norfloxacin or ciprofloxacin: 8 mg/L; MIC of imipenem: 2 mg/I). The frequency of in-vitro emergence of variants resistant to imipenem and fluoroquinolones was studied for the two strains, with imipenem or fluoroquinolones as selecting agents. Ciprofloxacin and three other quinolones (norfloxacin, temafloxacin and tosufloxacin) selected imipenem-resistant variants in a similar way to imipenem for the first strain, but not for the other. In contrast, imipenem did not select quinolone-resistant variants from either strain. For both strains, killing curves demonstrated that a bactericidal effect could be obtained with a drug combination (2 x MIC of ciprofloxacin and 2 x MIC of imipenem) without any selection of resistant mutants after 24 h, thereby suggesting the possible use of this combined regimen for treating severe P. aeruginosa infection.

Anti-Infective Agents↗
PubMed1992

Alternative therapeutic approaches in sleep apnea syndrome.

A number of therapeutic alternatives to continuous positive airway pressure (CPAP) and surgery have been proposed to treat sleep apnea syndrome. Nasopharyngeal intubation may provide an immediate, simple and cost-effective means of bypassing upper airway obstruction during sleep. Tolerance is good in small children but is lower, between 30 and 40%, in adults. Clinical improvement is reported by more than half of the patients treated with this device and is confirmed by polysomnography. However, in most of these subjects, breathing during sleep is only partially corrected and sleep remains fragmented. Nasopharyngeal intubation should be proposed in infants, in patients who do not tolerate CPAP or as a therapeutic substitute for CPAP during holidays or traveling. The tongue retaining device and variants of orthodontic appliances have been proposed in order to increase upper airway patency. Tolerance is low, efficacy is usually incomplete and limited to patients with moderate forms of SAS, and long-term follow-ups are scarce. Sleep position training has been advocated as a means of reducing time spent in the supine position. Long-term efficacy has not been proven. Weight loss by caloric restriction or surgical procedures produces a variable improvement of sleep architecture and breathing during sleep. It should be proposed to all patients with SAS, as cure has been achieved in a few patients with the adjunction of weight loss and another treatment modality.

Adult↗
PubMed1992

Immunoblotting patterns with Mycoplasma pneumoniae of serum specimens from infected and non-infected subjects.

Two hundred and ninety-four serum specimens from 248 subjects, whose complement fixation (CF) titres to Mycoplasma pneumoniae were known, were further investigated by IgG immunoblotting. After analysis of M. pneumoniae proteins by SDS-PAGE, nine polypeptides (p) with mol. wts of 180-43 Kda were selected for immunoblotting studies. Antibodies to M. pneumoniae measured by immunoblotting appeared progressively with age; most subjects more than 19 years old gave positive results. For most of the polypeptides, there was an increase in the frequency of band detection when the CF titres were higher. Furthermore, paired serum specimens from 10 patients with M. pneumoniae infection, as demonstrated by a rise in CF antibody titre, were tested for IgG blotting patterns. Generally, p180 (the P1 adhesin of M. pneumoniae), p172 and p84 were shown to be the dominant targets of the immune response to this organism and may have diagnostic value.

Adolescent↗
PubMed1992

Evaluation of five commercial tests: complement fixation, microparticle agglutination, indirect immunofluorescence, enzyme-linked immunosorbent assay and latex agglutination, in comparison to immunoblotting for Mycoplasma pneumoniae serology.

A panel of 68 serum specimens from 41 subjects exhibiting various immunological patterns to Mycoplasma pneumoniae as determined by detection of a 180 kDa protein in immunoblotting was used to compare five commercially available tests based on different methods: complement fixation test (CFT), microparticle agglutination (MAG), indirect immunofluorescence assay (IFA), enzyme-linked immunosorbent assay (Elisa), and latex agglutination (LA). The tests were performed according to the manufacturers' instructions. For the determination of immunity to M pneumoniae, the five tests were in good accordance with immunoblotting: sensitivity was 100% for all the five assays, specificity ranged from 95.6% (MAG) to 82.6% (Elisa) and overall agreement ranged from 98.2% (MAG) to 92.8% (Elisa). The comparisons of antibody rates obtained by the four quantitative tests (CFT, MAG, IFA, Elisa) showed correlation coefficients ranging from 0.87 (CFT-IFA) to 0.67 (CFT-Elisa). Six significant antibody rises demonstrated by immunoblotting patterns were detected by all the tests but Elisa in one case. As a whole, the commercial assays gave satisfactory results for routine determination of immune status to M pneumoniae: CFT was the cheapest test and MAG and LA were the easiest to perform.

Adolescent↗
PubMed1992

[Study of serum kinetics of vancomycin during the "antibiotic-lock" technique].

The serum kinetics of vancomycin was studied in two patients aged 3 and 15 years during antibiotic therapy for catheter related sepsis associated with Staphylococcus epidermidis. Vancomycin was administered, simultaneously, by parenteral conventional doses (30 mg/kg/day div q 8 h) and using the antibiotic-lock technique in the infected catheter at a high concentration (150 mg/ml) during one hour, 3 hours after each infusion. Pharmacokinetics data did not show any significant change in the serum kinetics of the antibiotic. The results suggest that delivering a high concentration of vancomycin in the infected catheter using the lock technique may be useful to sterilize infected catheter without toxic effect.

Adolescent↗
PubMed1991

[In vitro bactericidal effect of temafloxacin and tosufloxacin against streptococci].

Tosufloxacin tosylate (TOSU) and temafloxacin hydrochloride (TEMA) were tested in vitro against 248 clinical isolates of various species of streptococci recovered in a hospital microbiology laboratory (Bellevue Regional Teaching Hospital). Species included S. pneumoniae (n = 20), group A streptococci (n = 22), group B streptococci (n = 30), group G streptococci (n = 17), group D S. bovis (n = 19), Enterococcus faecium (n = 45), Enterococcus faecalis (n = 28), S. sanguis (n = 21), S. milleri (n = 29) and S. mitis (n = 17). Activities of each of the two study drugs were evaluated comparatively with two other fluoroquinolones, i.e., ciprofloxacin (CIP) and pefloxacin (PEF). Activities of each of these four antibiotics, expressed as the MIC 90%, varied as follows according to the species of streptococci: TOSU, 0.25 to 1 mg/l, TEMA 0.5 to 2 mg/l, CIP, 1 to 4 mg/l and PEF 8 to 32 mgl. Overall, TOSU and TEMA exhibited the greatest activity of the various species. The size of the inoculum had no significant effect on MIC values.

Anti-Infective Agents↗
PubMed1991

[In vitro effect of new fluoroquinolones and betalactamines combinations against enterococci].

Combinations of one of the new fluoroquinolones (ciprofloxacin, temafloxacin or tosufloxacin) with a betalactam (amoxicillin, piperacillin, or imipenem) were tested in vitro using the checkboard method against 28 strains of Streptococcus faecalis recovered in 1990 from a variety of specimens. No instance of antagonism (FIC greater than 2) was recorded. Effects of the two agents were usually additive (0.5 less than FIC less than or equal to 1). An indifferent effect (1 less than FIC less than or equal to 2) was seen in 32.1% of cases (9 strains) with the amoxicillin-tosufloxacin combination. Synergy (FIC less than or equal to 0.5) was uncommon with combinations including imipenem: effects were synergistic for only three strains with imipenem and either ciprofloxacin or tosufloxacin and for six strains with the imipenem-temafloxacin combination. Synergy was more common with combinations including ciprofloxacin and either piperacillin (10 strains, 35.7%) or amoxicillin (13 strains, 46.4%).

Amoxicillin↗
PubMed1990

The penetration of ceftriaxone into human brain tissue.

The cerebral penetration of ceftriaxone in patients who underwent surgery for cerebral tumours was investigated. Seventeen patients received 2 g of ceftriaxone given intravenously 2 to 13 h before blood and brain samples were taken. Antibiotic levels were determined by an agar-well diffusion method. Cerebral ceftriaxone concentrations ranged from 0.3 to 12 micrograms/g, with a mean value of 1.63 micrograms/g. These values were less than 2% of corresponding serum concentrations, but enough to inhibit 75% of bacterial strains recently isolated from brain abscesses in our unit.

Adult↗