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E Gaubert

Publications and source records attributed to E Gaubert.

6 recordsLinked to original sources

Maturation reveals a decrease in endothelium-dependent contraction induced by depolarization in the aorta of spontaneously hypertensive rats.

The influence of the endothelium on aortic contractility to KCl 100 mM was studied during maturation and aging in normotensive Wistar and spontaneously hypertensive rats (SHR). In Wistar rats, there was no significant difference in maximal responses in the course of aging whether the endothelium was present (E+) or not (E-). A similar result was obtained in SHR E- rings. However, contraction was significantly higher in E+ rings of young (9 weeks) compared to adult and old SHR (18, 25, 36 and 72 weeks) (in mN/mm2: 34.8 +/- 3.1 versus 24.8 +/- 1.8, 16.0 +/- 2.5, 17.4 +/- 2.0 and 12.9 +/- 1.8, p<0.01). This increase remained significant in 18- compared to that of 25-, 36- and 72-week-old rats (p<0.01). No change appeared with age in noradrenaline-induced contractions of E+ rings neither in Wistar nor in SHR. A dose-dependent decrease in response to KCl was observed after an in vivo pretreatment of the young SHR with acetylsalicylic acid. Finally, blocking the TXA2/PGH2 receptor by addition of GR 32191B or ONO-3708 led to a decrease in the response of young SHR aortic rings to KCl. This study points out a decrease in the response of SHR aortic rings to a depolarizing agent during maturation. The enhanced contraction observed in young SHR seems to be the result of an increased participation of an endothelium-derived, cyclooxygenase-dependent contracting factor(s), most likely either TXA2 or PGH2. This factor might play a key role in the onset of hypertension in the spontaneously hypertensive strain.

Aging↗

In vitro activity of sparfloxacin and other antimicrobial agents against genital pathogens.

The in vitro activity of sparfloxacin was determined for 60 strains of Neisseria gonorrhoeae, 15 strains of Chlamydia trachomatis and 40 strains each of Gardnerella vaginalis, Mycoplasma hominis, and Ureaplasma urealyticum and compared with those of ampicillin, azithromycin, clarithromycin, erythromycin, ofloxacin, temafloxacin and tetracycline. Sparfloxacin was active against all the strains studied and appeared to be the most potent quinolone tested. Sparfloxacin had the lowest MICs against N. gonorrhoeae (MICs 0.002-0.06 micrograms/ml). Its MICs against C. trachomatis (0.03-0.06 micrograms/ml) were higher than those of clarithromycin but lower than those of the other antimicrobial agents. Sparfloxacin was particularly active against tetracycline-susceptible as well as resistant strains of M. hominis (MICs, 0.06 micrograms/ml) and U. urealyticum (MICs 0.125-1 micrograms/ml). Because of this in vitro activity and its tissue distribution, sparfloxacin might be a valuable therapeutic agent for treating major bacterial sexually transmitted diseases.

Ampicillin↗

[First isolation in France of a penicillinase-non producing Neisseria gonorrhoeae with high level tetracycline resistance].

We report the first isolation in France of a penicillinase-non producing Neisseria gonorrhoeae with high level tetracycline resistance. The minimal inhibitory concentrations (MICs) of nine antibiotics were determined by agar dilution for the tetracycline resistant strain and 39 other penicillinase-non producing N. gonorrhoeae strains which were isolated during the same year (1989), in Toulouse. No difference was observed between the MICs except for the tetracycline (tetracycline-resistant strain MIC = 32 mg/l). The commonly used antibiotics other than tetracycline were active in vitro against all the strains. The plasmid content of the tetracycline-resistant strain was analysed by agarose gel electrophoresis and revealed the presence of two plasmids: the 2.6-megadalton in cryptic plasmid and the 25.2-megadalton Tet M conjugative plasmid.

Anti-Bacterial Agents↗

[In vitro activity of 5 new quinolones against Gardnerella vaginalis].

The minimal inhibitory concentrations (MICs) of five new quinolones were determined by agar dilution, for 50 clinical isolates of Gardnerella vaginalis. They are compared with those of metronidazole, ampicillin, erythromycin and tetracycline which are widely used for the treatment of lower genital tract infections in women. The MICs of rosoxacin and pefloxacin are high, but those of ofloxacin (MIC 50, 2 mg/l), fleroxacin (MIC 50, 2 mg/l) and ciprofloxacin (MIC 50, 1 mg/l) are lower. They can explain the effectiveness observed with this latter antibiotic in vivo, and allow their clinical experiment.

Ampicillin↗

In vitro activity of six quinolone derivatives against Neisseria gonorrhoeae.

The in vitro activities of six quinolone derivatives, rosoxacin, pefloxacin, ofloxacin, ciprofloxacin, A-56619 and A-56620, were compared with those of penicillin, cefotaxime, spectinomycin, chloramphenicol, tetracycline and erythromycin against 50 nonpenicillinase-producing and 15 penicillinase-producing Neisseria gonorrhoeae strains. Ciprofloxacin was the most active compound in vitro (MIC50, 0.004 mg/l) followed by ofloxacin and A-56620 (MIC50, 0.008 mg/l), A-56619 and cefotaxime (MIC50, 0.016 mg/l). The six quinolones are highly active against all the strains tested but 2, with decreased sensitivity.

Anti-Bacterial Agents↗

[Surveillance of Neisseria gonorrhoeae strains isolated in Toulouse. In vitro antibiotic sensitivity and plasmid content].

The minimal inhibitory concentration (MIC) of twelve antibiotics was determined by the method of dilution in agar for 50 non penicillinase-producing and 15 penicillinase-producing Neisseria gonorrhoeae (PPNG) strains. The commonly used antibiotics are active in vitro against all the strains. For the non PPNG stains, no difference was observed between the MICs with a previous investigation, in 1980. New quinolones are highly active against all the strains tested but two, with decreased sensitivity. Since 1980, 16 PPNG strains were isolated (2.2%) and analysed for plasmid content. Asian type plasmid (7.4 kb) was present in 9 strains and african type (5.3 kb) in 7 strains. The conjugative plasmid (39 kb) was present in 5 strains and the cryptic plasmid (4.4 kb) in all the strains.

Anti-Bacterial Agents↗