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H Monteil

Publications and source records attributed to H Monteil.

At least 199 records · Page 11Linked to original sources

Membrane ATPase of Proteus L-forms. Solubilization and molecular properties.

The Mg2+ -dependent ATPase (EC 3.6.I.3) of Proteus L-form membrane has been solubilized according to various procedures (Tris - HCL shock-wash with or without MG2+, EDTA, Triton X-100). The best results were obtained by the same 33mM Tris-HCL (pH 7.5) shock-wash without MG2+ used for ATPase of protoplasts from Streptococcus faecalis. The solubilized enzyme after 105 000 times g centrifugation was purified on acrylamide/agarose. The molecular weight was established to be 360 000 by gel filtration and by sedimentation coefficient (12.5 S). Polyacrylamide disc-gel electrophoresis in sodium dodecylsulphate revealed two classes or subunit of mol. wt. 64 000 (alpha) and 58 000 (beta), associated in ratio 1:1. We propose a formula alpha-3beta-3 for the native ATPase of Proteus L-forms. Structural similarities to ATPase of various origins are discussed.

Adenosine Triphosphatases↗

Investigation of the biliary clearances of cefotaxime and desacetylcefotaxime by an original procedure in cholecystectomised patients.

The biliary elimination of cefotaxime (CTX) and its metabolite desacetylcefotaxime (DSCTX) were measured by HPLC in nine recently cholecystectomised patients following the i. v. injection of 15 mg/kg body weight of CTX. All of the bile was collected by an original procedure: the inflated balloon of a Fogarty catheter was introduced into the distal branch of a Kehr drain T-tube. Biliary clearance of CTX and DSCTX was measured for 8 h. Cefotaxime peaked at 90 min after injection at 34.5 +/- 15.3 mg/l; in the 7-8 h sample it was 2.7 +/- 1.7 mg/l. DSCTX peaked at the same time at 49.3 +/- 17.0 mg/l, and was 4.6 +/- 3.2 mg/l at 8 h. The bile/serum ratio of CTX and DSCTX concentrations was above 1 from the first to the eighth hours (range: 1.35 +/- 1.08 to 11.0 +/- 3.1). The biliary clearance of CTX was 0.190 ml/min. The total amounts of CTX and DSCTX eliminated in bile were respectively 1050 +/- 472.8 micrograms and 1902.7 +/- 804.1 micrograms (0.093 +/- 0.041% of the dose and 0.186 +/- 0.077% of the dose). Considering the minimum inhibitory concentration of the pathogens currently encountered in biliary sepsis, CTX should be a suitable antimicrobial agent for the treatment of biliary infections.

Adult↗

Ciprofloxacin biliary disposition in cholecystectomised patients with special references to HPLC and bioassay data.

The biliary disposition of ciprofloxacin was studied in 12 recently cholecystectomised patients during 24 hours following a single oral administration of 500 mg of the drug. Ciprofloxacin was measured in serum, urine, bile and faeces by both high performance liquid chromatography (HPLC) and bioassay. The results were found to be comparable for the concentrations in serum (mean Cmax = 0.97 +/- 0.17 microgram/ml by HPLC and 1.08 +/- 0.19 microgram/ml by bioassay) and in urine (0.6 h: 267 +/- 74 micrograms/ml and 241 +/- 58 micrograms/ml respectively). Higher concentrations were found in bile when measured by bioassay compared with HPLC (peak concentration = 10.3 +/- 3.4 micrograms/ml and 7.5 +/- 2.8 micrograms/ml respectively; p less than 0.02). The total biliary elimination was also significantly higher according to bioassay data (2167 +/- 288 micrograms/ml versus 1587 +/- 222 micrograms/ml; p less than 0.01). This suggests a first pass effect and hepatic biotransformation of ciprofloxacin to one or more active metabolite (s).

Administration, Oral↗

Penetration of roxithromycin into gingival tissue.

Roxithromycin is a new macrolide with an antibacterial spectrum similar to that of erythromycin. Absorption is rapid and complete, resulting in high serum levels and a long half-life. Tissue distribution is extensive and sustained, as shown by the high concentrations measured in the lung, prostate, ovaries, liver, kidney, and skin. In this study, we measured the penetration of roxithromycin into gingival tissue at steady state in 30 patients treated orally with 150 mg every 12 hr for 5 days. Tissue specimens were sampled at 2, 4, 6, 8, or 12 hr (n = 6 each time) after dose 10, and blood samples were taken simultaneously. Serum and tissue concentrations of roxithromycin were measured by high-performance liquid chromatography. The peak serum level, reached 4 hr after dosing, was 6.60 +/- 1.15 micrograms/ml. The peak tissue level was 4.63 +/- 1.84 micrograms/g and was reached after 8 hr. From 4 to 10 hr after dosing, tissue concentrations were greater than 2 micrograms/g, that is, higher than the MIC90 of roxithromycin against most oral pathogens. These data support the use of roxithromycin in the treatment of oral infections.

Absorption↗

Identification of Flavobacterium strains by gas liquid chromatographic analysis of volatile fatty acids produced in culture.

The classification previously established for 74 Flavobacterium strains by gas liquid chromatographic (GLC) analysis of volatile fatty acids (VFA) produced in culture allowed the recovery of 9 groups (J. gen. Microbiol., 1986, 132, 2723-2732). Since graphic representation of the strains based on the first 3 factors obtained by principal component analysis (PCA) clearly separated these groups, we tried to identify 80 new strains by comparing their positions with those of the 9 groups, on the basis of both hierarchical classification and PCA methods. Of the 153 strains studied, only 12 were not allocated to a group corresponding to their original biochemical identification. Thus, on the whole, this characterization method by GLC analysis seemed satisfactory, although it could not be established whether the method was adequate for routine identification, or would serve merely as a complement.

Chromatography, Gas↗

Phenylmercuric acetate biodegradation by environmental strains of Pseudomonas species.

Organomercurial pollution occurring in the Rhine river in 1986 led us to study the possibility of depollution by mercury-resistant environmental aquatic strains. Four species of Pseudomonas were investigated for their ability to biotransform phenylmercuric acetate (PMA). Such biological depollution was demonstrated to be due to an enzymatic activity in whole cells and in cell-free extracts from Pseudomonas fluorescens and other Pseudomonas species. PMA biotransformation was followed by high-performance liquid chromatography. Some of those bacteria growing between 4 and 41 degrees C probably represent a natural means of organomercurial depollution, which acts slowly in interaction with other organisms and non-organic porous surfaces.

Biodegradation, Environmental↗

Corynebacterium group D2 ("Corynebacterium urealyticum") constitutes a new genomic species.

Twenty-one Corynebacterium group D2 ("C. urealyticum") strains were found to constitute a tight DNA hybridization group distinct from named Corynebacterium species. The strains of Corynebacterium group D2 had cell wall component type IV, short chain mycolic acids and G+C content of DNA of 65-66 mol %. Corynebacterium group D2 constitutes a genomic species which can be identified by phenotypic tests.

Base Composition↗

[Biliary excretion of cefotaxime and desacetylcefotaxime].

The biliary excretion of cefotaxime (CTX) and its metabolite desacetylcefotaxime (DSCTX) was measured by HPLC in 9 recently cholecystectomized-patients following the IV injection of 15 mg/kg body weight of CTX. The totality of bile was collected by an original procedure: the inflated balloon of a Fogarty catheter was introduced into the distal branch of a Kehr drain T-tube. Biliary clearance of CTX and DSCTX was measured for 8 h. Cefotaxime peaked at 90 min. after injection at 34.5 +/- 15.3 micrograms/ml; in the 7-8 h sample it was 2.7 +/- 1.7 micrograms/ml. DSCTX peaked at the same time at 49.3 +/- 17.0 micrograms/ml, and was 4.6 +/- 3.2 micrograms/ml at 8 h. The bile/serum ratio of CTX and DSCTX concentration was 1 from the 1st to the 8th hours (range: 1.35 +/- 1.08 to 11.0 +/- 3.1). The biliary clearance of CTX was 0.190 ml/min. The total amounts of CTX and DSCTX eliminated in bile were respectively 1050 +/- 472.8 micrograms and 1902.7 +/- 804.1 micrograms (0.093 +/- 0.041 p. 100 of the dose and 0.186 +/- 0.077 p. 100 of the dose). Considering the minimum inhibitory concentration of the pathogens currently encountered in the biliary sepsis, CTX should be a suitable antimicrobial agent for the treatment of biliary infections.

Adult↗

Pseudomonas cepacia typing systems: collaborative study to assess their potential in epidemiologic investigations.

To determine the utility of available Pseudomonas cepacia typing systems for confirming the relatedness of isolates, we applied these methods to isolates associated with previously investigated nosocomial outbreaks. We compared chromosome analysis, serologic reactions, biochemical tests, bacteriocin production and susceptibility, and antimicrobial susceptibility in their ability to determine outbreak relatedness. Chromosome analysis, serologic reactions, and biochemical tests were each demonstrated to be epidemiologically useful methods for typing isolates. Determination of the sensitivity and specificity of these typing techniques will facilitate their application in the epidemiologic study of this increasingly important nosocomial pathogen.

Chromosomes, Bacterial↗