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B Picard

Publications and source records attributed to B Picard.

At least 127 records · Page 7Linked to original sources
PubMed1986

Characterization of Enterobacter cloacae and E. sakazakii by electrophoretic polymorphism of acid phosphatase, esterases, and glutamate, lactate and malate dehydrogenases.

Acid phosphatase, esterases, and glutamate, lactate and malate dehydrogenases of 34 strains of Enterobacter cloacae and 22 strains of Enterobacter sakazakii were analysed by horizontal polyacrylamide agarose gel electrophoresis and by isoelectrofocusing in thin-layer polyacrylamide gel. The two species could be separated on the basis of distinct electrophoretic patterns of all enzymes analysed. Glutamate dehydrogenase and acid phosphatase were detected exclusively in E. cloacae, whereas esterase bands were more intensively stained in E. sakazakii. For each species, two zymotypes could be distinguished, on the basis of electrophoretic mobilities of malate dehydrogenase and banding patterns of esterase for E. cloacae, and by both isoelectric point and electrophoretic mobilities of an esterase and of lactate and malate dehydrogenases for E. sakazakii. The high degree of enzyme polymorphism within the two species permitted precise identification of strains. The variations in electrophoretic patterns might therefore provide useful epidemiological markers.

Acid Phosphatase↗
PubMed1986

Comparative esterase electrophoretic polymorphism of Escherichia coli isolates obtained from animal and human sources.

To determine whether enzyme electrophoretic polymorphism in Escherichia coli populations was influenced by environmental background, the mobilities of four electrophoretically variable esterases (A, B, C and I) were examined. The distinction between isolates was established by significant differences in the electrophoretic distribution and the genetic diversity coefficient of individual esterases. Principal components analysis on each population and on all strains revealed three groups of allozymes. The first, characterized by slow electrophoretic mobilities of esterase B, was frequently observed in strains obtained from human extra-intestinal infections and rarely in commensal organisms. The second, characterized by fast mobilities of esterases A and B, was frequently found in animal isolates. The third, characterized by prominence of the most common mobilities of esterases B and A, was recovered in all populations. These results were confirmed by discriminant analysis. Among the 610 strains investigated, 316 electrophoretic types (distinctive combinations of allozymes of the four varieties of esterases) were distinguished, illustrating high esterase polymorphism.

Animals↗
PubMed1986

Highly pathogenic strains of Escherichia coli revealed by the distinct electrophoretic patterns of carboxylesterase B.

One hundred and ninety one strains of Escherichia coli isolated from extra-intestinal infections and 85 strains isolated from the stools of healthy human beings were compared for electrophoretic mobility and isoelectric point of carboxylesterase B, and for production of alpha-haemolysin and the presence of mannose resistant haemagglutinin. Fast and slow electrophoretic mobilities were distinguished among the strains. The frequency of strains showing slow mobilities was considerably higher when they originated from extra-intestinal infections (40%) than when they were obtained from the stools of healthy individuals (7%). In a two-dimensional electrophoretic profile, the fast and slow mobility variants of carboxylesterase B were resolved into two patterns, B1 and B2, respectively. The frequency of pathogenic strains that concomitantly produced alpha-haemolysin and mannose resistant haemagglutinin was 48.7% for strains of pattern B2 but only 2.8% for strains of pattern B1. Thus, the electrophoretic pattern B2 of carboxylesterase B appears to be a molecular marker for a group of highly pathogenic E. coli strains which are frequently implicated in extra-intestinal infections.

Bacterial Proteins↗
PubMed1986

[Value of short prophylactic antibiotherapy in thoracic and vascular surgery. Comparative randomized double-blind study of 3 and 8 injections of cefamandole].

The subject of whether an optimal duration of prophylactic antibiotic therapy exists was evaluated by comparing results of short and medium-term treatment in aseptic surgery during a double-blind, randomized, prospective trial in 507 patients undergoing vascular or thoracic operations. Patients were randomly allocated to receive either 3 injections of cefamandole: at induction of anesthesia and after 4 and 10 hours (251 cases) or 8 injections of the same antibiotic: at induction of anesthesia, after 4 hours and then every 6 hours up to 40 hours (256 cases). Evaluation on discharge showed that among the 251 patients receiving 3 injections, 21 (8.33%) were infected while in the group treated with 8 injections (256 cases) 25 (9.8%) were infected. The X2 was 0.25 and there is a lack of statistically significant difference between treatments. Duration of prophylactic antibiotic therapy can be shortened, without loss of efficacy in thoracic or vascular aseptic surgery, to reduce selection of resistant germs and to lower costs.

Bacterial Infections↗
PubMed1985

Comparative electrophoretic profiles of esterases, and of glutamate, lactate and malate dehydrogenases, from Aeromonas hydrophila, A. caviae and A. sobria.

Esterases, and glutamate, lactate and malate dehydrogenases of 64 Aeromonas hydrophila, A. caviae and A. sobria strains, were analysed by polyacrylamide agarose gel electrophoresis and by thin layer isoelectrofocusing. On the basis of the isoelectric points of malate dehydrogenase from the three species and the mobility of lactate dehydrogenase from A. sobria, 8 species specific zymotypes were defined: three for A. hydrophila strains, three for A. caviae strains and two for A. sobria strains. These zymotypes correlated with previously established DNA hybridization groups. The other electrophoretic data were found to be less useful for distinction between A. hydrophila and A. sobria strains, but supported differentiation into zymotypes for A. caviae strains. The two-dimensional electrophoretic profile established by plotting isoelectric point against electrophoretic mobility of the major esterase illustrated the degree of enzyme polymorphism among the strains of the three species. Variation in electrophoretic patterns within A. hydrophila and A. caviae might provide useful epidemiological markers.

Aeromonas↗
PubMed1984

[Aeromonas hydrophila septicemia. Epidemiologic aspects. 15 cases].

Fifteen cases of Aeromonas hydrophila septicaemia, characterized by their frequent pulmonary lesions and the severity of their course, are reported. The delay observed between admission to hospital and first symptoms, together with the presence of anatomical lesions or physiological disturbances suggesting bacterial invasion by the intestinal route, have led the authors to postulate a nosocomial digestive contamination, probably from water, as suggested by the particular ecology of this micro-organism. This hypothesis was supported by the finding of Aeromonas hydrophila in large numbers at the different points of the hospital water distribution system where samples were taken.

Adult↗
PubMed1984

[Electrophoretic typing of Escherichia coli esterases in septicemia].

Esterases produced by 175 strains of Escherichia coli isolated from 34 patients with septicaemia were subjected to electrophoresis in acrylamide-agarose gel. Forty-four electrophoretic types were identified, and the septicaemias were divided into two groups according to whether or not all the strains isolated in a given patient were of the same electrophoretic type. In the first group (21 patients) the presence of one single electrophoretic type demonstrated that the strains isolated from haemocultures and those isolated from focal specimens were identical and could be held responsible for infection in different foci. In the second group (13 patients) the presence of different electrophoretic types in the same patient either discard an relationship between strain from haemoculture and strain from focal specimen, or demonstrated that different strains could coexist in a focus of infection, or revealed successive and overlapping infections. These results not only provide precise information on the nature of bacteria responsible for infections, but also have interesting pathophysiological and epidemiological implications.

Electrophoresis↗
PubMed1984

Distinctive electrophoretic and isoelectric focusing patterns of esterases from Yersinia enterocolitica and Yersinia pseudotuberculosis.

Esterases of 53 strains of Yersinia enterocolitica sensu stricto, including five previously defined biotypes, and 30 strains of Yersinia pseudotuberculosis were analysed by horizontal polyacrylamide-agarose gel electrophoresis and by isoelectrofocusing in thin-layer polyacrylamide gel. Esterase bands were defined by their range of activity towards several synthetic substrates, their resistance to heat and to di-isopropyl fluorophosphate. The two species were characterized by distinct electrophoretic patterns of their esterases. The apparent molecular weights of the heat-resistant esterase of Y. enterocolitica and of the major heat-resistant esterase of Y. pseudotuberculosis, as determined by polyacrylamide gradient gel electrophoresis, were estimated to be 52 000 and 250 000, respectively. On the basis of electrophoretic mobilities and isoelectric points of esterases produced by strains of Y. enterocolitica, five principal zymotypes were observed: two for strains of biotype 1, two for strains of biotypes 2 and 3, respectively, and only one for strains of both biotypes 4 and 5. The zymotypes of strains of biotypes 2, 3, 4 and 5 appeared to be more closely related to one another than to zymotypes of strains of biotype 1. Variations in number or mobility of bands observed within each biotype of Y. enterocolitica and within some serotypes of Y. pseudotuberculosis could represent an additional marker for epidemiological analysis.

Electrophoresis, Polyacrylamide Gel↗
PubMed1983

[Study of critical levels of 3 antistreptococcal antibodies by data analysis].

Prinqual, a new statistical data-analysis method was used to determine the critical titers of antistreptolysin O (ASLO), anti-DNase B (ADB) and antistreptokinase (ASK) in the sera of 104 patients with suspected streptococcal infection and 121 blood-donors. The whole range from pathological to normal was thus covered, thereby avoiding bias concerning the proportion of normal titers in a control population. Another advantage of the method was that the titers of the 3 antibodies were considered simultaneously and the semi-quantitative results of serological tests were avoided. It appeared from this study that the upper limits of normal values were: ASLO, 100 U; ADB, 240 U and ASK, 40 U. The first probably pathological values were: ASLO, 150 U; ADB, 480 U and ASK, 320 U. These results are compared with those available in the literature.

Antibodies, Bacterial↗