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Y Buisson

Publications and source records attributed to Y Buisson.

87 records · Page 5Linked to original sources
PubMed1985

[Gonococcus producers of beta-lactamase isolated in Dakar. Sensitivity to different antibiotics, auxotype and plasmid content].

More than 12.5% of gonococci isolated in Dakar during the first six months of 1984 were penicillinase producers (PPNG). PPNG strains were susceptible to a number of antibiotics: spectinomycin, thiamphenicol and tetracycline. No significant differences were found between distribution of auxotypes in PPNG and in non-penicillinase producing strains. Study of plasmidic content of PPNG (36 strains isolated from 1981 to 1984) revealed that 68.75% were of the "African" type and 31.25% of the "South-East Asian" type. Ratio of isolation of these two plasmidic content types remained consistent throughout the last four years. The criteria defined in 1977 to classify PPNG into two types need to be reviewed, specifically with regard to geographical areas, auxotype and tetracycline susceptibility. We found a significant correlation between the 4.5 Md plasmid (bla+) and the auxotype (PRO-). This finding has been reported by other authors but has not yet been explained.

Anti-Bacterial Agents↗
PubMed1985

[Endemic syphilis in a Sahelian area of Burkina Faso. Sero-clinical survey].

In March 1981, we studied a traditional focus of endemic syphilis in a Sahelian area in North-East of Burkina-Faso. The clinical survey was conducted on a sample of 1 600 people and showed a prevalence of contagious clinical lesions of 5.6% in children and 1.8% in adults. The seroimmunological study, effected with passive haemagglutination test (T. P. H. A.), showed that 47.1% of the individuals were bearing antitreponemic specific antibodies; the seroimmunological prevalence increases with age, from 29.2% in the 5-9 years old children up to 85.2% in adults 60 years old and over. Clinical and serological prevalences are all the more important as the conditions of hygiene are worse. In comparison with the last campaigns of penicillinotherapy, conducted in 1962, a recrudescence of syphilitic endemic is to be noted.

Adolescent↗
PubMed1984

[Epidemiologic approach to gonococcal infections in Senegal through the study of auxotypes].

287 strains of Neisseria gonorrhoeae isolated in Dakar during a 26 months period (April 1981-May 1983) were sent to Pasteur Institute of Paris for auxotyping. They are distributed in (+): 56%, (PRO-): 21%, (ARG-): 13%, and nine minor auxotypes to the exclusion of (AHU-). Auxotypes distribution according to the sex, the kind of samples and the race do not give proof of significant difference. Monthly distribution shows an endemic circulation of auxotypes (+) and (PRO-), as well as an unstability of auxotype (ARG-) that was prevailing in early months. 22 strains of penicillinase-producing Neisseria gonorrhoeae (among which the first strains isolated in Senegal) belong to auxotypes (+), (PRO-) and (PRO-, ARG-). This distribution does not differ from that of non-producer strains. Gonococcal auxotyping provides an useful epidemiologic marker in order to search after the source of a contamination, to discern a failure of the treatment from a later infection and, on a wide plan, to survey the resistant strains spreading.

Adult↗
PubMedDate not supplied

Hepatitis B virus type 2 infection in France.

Hepatitis B type 2 infection was observed in 96 French soldiers. A recent stay overseas was reported by 65% of them and an HBsAg chronic carrier state was observed in eight individuals. Anti-pre-S1 and anti-pre-S2 antibodies were not detected after recovery, but HBV DNA was detected in 58% of sera tested.

Adolescent↗
PubMedDate not supplied

Antibody response to preS1 in hepatitis-B-virus-induced liver disease and after immunization.

Antibodies to the pre-S1-encoded sequence of hepatitis B virus (HBV) envelope were detected by ELISA using a synthetic peptide analogue of preS1 proteins, in different groups of HBV-infected subjects and also in hepatitis B vaccine recipients. Such antibodies were specifically found in only 1% of HBsAg chronic carriers including patients with cirrhosis and primary liver cancer. Anti-preS1 were detected in patients with acute hepatitis; in 13% of the HBsAg+ sera obtained before recovery and in 37% of the sera obtained after recovery. Anti-preS1 antibodies were detected in recipients of a plasma-derived vaccine, but not in those receiving a recombinant vaccine. The results indicate that anti-preS1 is an earlier serum marker of HBV clearance than anti-preS2 and anti-S antibodies.

Adult↗
PubMedDate not supplied

Hepatitis type E in a French population: detection of anti-HEV by a synthetic peptide-based enzyme-linked immunosorbent assay.

Four synthetic peptides were used to develop an ELISA for detecting hepatitis type E infections. Antibodies to HEV were detected in 54 of 64 patients present during two outbreaks previously recognized as being due to hepatitis E virus. Those patients included French soldiers stationed in Chad at the time, and Algerian civilians residing in Algeria and considered as positive controls. Anti-HEV were also detected in 3 out of 74 cases of sporadic non-A, non-B, non-C hepatitis in France, and in 2 out of 150 anti-HAV-IgM-positive sporadic cases, also in France, but in none of 278 healthy adults from the general French population. Among a total of 34 anti-HEV-positive cases in French subjects, 32 were shown to be associated with travel outside of western Europe; in two cases, however, HEV transmission appeared to have taken place in Europe. Using this ELISA, a rapid drop in anti-HEV antibodies to undetectable levels following the acute phase of the disease was observed in a high proportion of the infected subjects. Thus, the present test would appear to be more suitable for diagnostic purposes than for epidemiological investigations.

Adult↗
PubMedDate not supplied

[Acute transverse cervical myelitis following hepatitis B vaccination. Evolution of anti-HBs antibodies].

BACKGROUND: The cause and effect relationship between anti-HBV immunization using recombinant vaccine and the development of a neurological event, including flare-ups of multiple sclerosis, is a widely debated issue. CASE REPORT: A previously asymptomatic 16-year-old girl was a hyper-responder to anti-HBV vaccine. Subsequent to a booster shot of anti-HBV recombinant vaccine, she developed regressive acute cervical transverse myelitis with intrathecal oligochonal IgG secretion and a hypersignal on the MRI T2 sequences of the cord. DISCUSSION: The distinction between a first episode of multiple sclerosis or post-vaccinal acute myelitis in this case will depend upon subsequent course, but this observation points out the very high level of persistent post-vaccinal immunization which can be acquired by a hyper-responder.

Adolescent↗
PubMedDate not supplied

[Geographical distribution of hepatitis E virus genotypes].

Hepatitis E virus (HEV) is the major agent of acute hepatitis in developing countries where the infection occurs sporadically or in large waterborne epidemics. HEV, classified in the Caliciviridae, is not culturable. The detection of HEV RNA by RT-PCR in serum and stool samples is reliable during the 7 to 15 days following the onset of the disease. Restriction endonuclease analysis, cloning and sequencing of PCR products allow a phylogenetic analysis of HEV isolates. Although they belong to a single serotype, strains recovered from different geographical regions display a significant genetic heterogeneity. Sequencing data from ORF1 and ORF2 regions has led to the characterization of 3 distinct genotypes: genotype I gathering the Asian and African subgenotypes; genotype II gathering swine and human US strains; genotype III limited to the Mexico prototype. Novel variants are currently described from Africa (Nigeria), China and Europe (Greece and Italy). Each genotype appears to be related to a well defined geographical area. Nevertheless, a genetic variability is observed within endemic regions such as Asia or Africa. Nigerian endemic isolates especially could represent an intermediate stage in the evolutionary process towards genetic diversity. The animal reservoir, proved by the detection of HEV sequences by PCR among pigs in Nepal and in the USA, could help to resolve unanswered questions about the origin of HEV genotypes, their spread and evolution.

Africa↗
PubMedDate not supplied

[Food poisoning outbreaks: an epidemiological study].

The occurrence of foodborne disease outbreaks (FDO) is increasing in industrialized countries. Most of these outbreaks (2/3) are notified from restaurants and other commercial establishments but more and more from households. Salmonella is the major agent of FDO, especially S. enteritidis for five years. However, its role may be overestimated because inadequate microbiological techniques routinely performed. Despite recent progress, several outbreaks still go unnoticed. Every outbreak should be early investigated, with methodical collection of clinical, bacteriological and food data, followed by statistical analysis. Once identified the responsible pathogen, the contaminated food, the source of contamination and the bacterial growth enhancing factors, rapid control measures can prevent further epidemics. Compulsory notification of all FDO to the public health services is the condition for the reliability of a national surveillance programme.

Foodborne Diseases↗
PubMedDate not supplied

[Effects of nifuroxazide on fecal flora in healthy subjects].

Effect of nifuroxazide on fecal flora was studied in 12 healthy volunteers receiving, in hazardous order and double-blind procedure, three six-days courses of treatment separated by eight-days spaces of time: the conventional dosage of 400 mg twice a day, a dosage of 1200 mg once a day, and placebo. Among six settled bacteriological index (wealth of the fecal flora, percentage of gram-negative bacteria, numbers of E. coli, Enterococcus, Clostridium and Bacteroides), no significant variation was found by means of statistical study between D0, D2 and D7, nor between the three courses of treatment. Therefore nifuroxazide, even in high dosage, does not injure integrity of microbial intestinal ecosystem under so defined experimental conditions, similar with clinical conditions.

Adult↗
PubMedDate not supplied

[Activities in the Senegalese National Center of Enterobacteria in 1980, 1981 and 1982].

1,589 strains of Salmonella and 192 strains of Shigella have been studied in the Senegalese National Center of Enterobacteria during 1980, 1981 and 1982. By the side of typhoid fever which remains the most frequent salmonellosis in Senegal (51.4% of human isolates), hospital-acquired salmonellosis have to be separately dealt with ( S. ordonez in 1980, S. chester in 1981, S. ibadan in 1982), characterized by high infantile mortality and constant multiple resistance to antibiotics. A country investigation showed the carriage of numerous and different serotypes in men and animals. Shigella strains isolated in Senegal keep yearly a similar antigenic distribution. On the other hand, occurrence of resistant strains (to ampicillin, tetracycline, trimethoprim -sulfamethoxazole) seems to be increasing.

Animals↗
PubMedDate not supplied

[Biological diagnosis of hepatitic C virus infections].

Biological diagnosis of HCV infections consists of a two steps process. The first one is the detection, rarely induced by evocative symptoms, more often subsequent to systematic screenings. Third generation ELISA tests are used for this purpose on account of their high sensitivity. Their enhanced specificity, reaching 99.5%, still has to be checked using complementary tests, especially immunoblots assays. However, these methods may fail to detect specific antibodies during the acute phase of HCV infections or among immunodeficient patients, resulting in discrepancies or indeterminate conclusions. Then, the detection of HCV viremia by PCR is of great value to assert the diagnosis. The second step, before treatment, consists to identify the genotype and to determine the viral load by quantitation of the HCV RNA. Because the endemicity of HCV infections in France, these methods, although difficult an expansive, should be transferred to the medical laboratories, provided their quality and their accessibility will be preserved.

Genotype↗
PubMedDate not supplied

[Toxic food infection caused by Shigella flexneri in a military unit].

Food borne disease outbreaks have increased in France, but outbreaks caused by Shigella are rare, accounting for only 73 cases (1.62%) in 1993. We report a food borne outbreak of Shigella flexneri strain 3 infection in a fire fighting unit in Paris between July 13th and 17th 1995. Forty of the 127 firemen suffered symptoms including acute diarrhea (80%), fever (50%) and blood and mucus in stools (1 case, 2.5%). Epidemiological investigation generated an unimodal epidemic curve suggesting a single source of contamination with no secondary cases. The median incubation period was between 43 hours 30 minutes and 51 hours 30 minutes. This is consistent with food borne Shigella infection. Statistical analysis of a case-control study implicated a mixed salad containing frozen shellfish from Asia (shrimps and mussels), served at lunch and dinner on July 13th 1995. Shigella was not detected in this salad by microbiological methods. However, inoculation with as little as 100 organisms can cause symptoms. There was low-level contamination with Escherichia coli (940 cfu/g) due to cross-contamination. Shigella flexneri strain 3 was isolated from 11 of 18 stool cultures, but was never isolated from cultures of stools provided by the cooks. All isolates had identical antibiotic resistance profiles. They were resistant to ampicillin and ticarcillin, moderately sensitive to amoxicillin-clavulanic acid, highly sensitive to aminosides, erythromycin and quinolones. This identical pattern in all isolates suggests a common source of contamination. Plasmid-based multiple resistance is common in this organism. Therefore, antibiotics should only be given to patients with evident clinical signs of infection. Treatment was symptom-based in all but 4 patients, who had acute diarrhea and were treated with ciprofloxacin. This antibiotic is well tolerated, has rapid bactericidal action and significantly reduces the duration of the symptoms and excretion of Shigella, thus preventing secondary contamination with this highly infectious bacterium. Thus, food borne outbreaks of Shigella can occur in countries with a high standard of living because of the increase in mass catering (e.g. fast food restaurants) and importation of foodstuffs from developing countries with endemic shigellosis. This is a public health problem because of the morbidity and absenteeism due to illness, particularly when the patients are firemen responsible for emergency management.

Amoxicillin↗