Search PubMed⌕ Search

Biomedical subjects

M Mounier

Publications and source records attributed to M Mounier.

At least 55 records · Page 3Linked to original sources

Alterations in the human immune response to the hepatitis B vaccine among the elderly.

The specific binding of hepatitis B (HBs) antigen by lymphocytes from old people immunized with hepatitis B vaccine was explored. For that purpose HBs antigen was combined with fluorescent microspheres, and labeled antigen was allowed to react with lymphocytes from HBs vaccine-responsive or unresponsive people. Lymphocytes from 10 responders and 14 nonresponders were tested for their antigen-binding ability. For controls, lymphocytes were incubated with microspheres bearing human albumin. Lymphocytes from 8 out of 10 responders were able to recognize HBs antigen; for the nonresponders the ratio was 9 out of 14. HBs-binding lymphocytes were B cells but not T lymphocytes. B and T cells from responders and nonresponders were combined and cultivated for 8 days in the presence of HBs antigen, and antibody-producing cells were counted. Neither B cells alone nor B cells plus T cells from nonresponders were able to produce antibody. On the other hand B cells from unresponsive old people produced antibodies when they were cultivated in the presence of HBs antigen and T cells from responsive old people. These data suggest that some elderly individuals who do not produce antibody after in vivo immunization by HBs vaccine do have antibody-producing cells. Instead of a gap in their immune repertoire, these people are suffering from immune dysfunction.

Aged↗

Prevalence of human T-lymphotropic retroviruses type III (HIV) and type IV in Ivory Coast.

Serological investigations in the Ivory Coast indicate that, despite the rarity of overt acquired immunodeficiency syndrome (AIDS), human immunodeficiency virus (HIV) is widely prevalent. So also is human T-lymphotropic virus type IV (HTLV-IV). The highest rates of HIV and HTLV-IV seropositivity were observed in female prostitutes. These findings suggest that, like HIV, HTLV-IV can be transmitted by heterosexual contact, and that the mobility of prostitutes may be an important factor in spread of the retroviruses in Africa. The incidence of HIV-associated AIDS in the Ivory Coast is likely to rise sharply in the next few years.

Acquired Immunodeficiency Syndrome↗

A STLV-III related human retrovirus, HTLV-IV: analysis of cross-reactivity with the human immunodeficiency virus (HIV).

A category of viruses has been identified which is related to human immunodeficiency virus (HIV) but is more closely related to a group of simian retroviruses (STLV-III). These viruses named HTLV-IV, LAV-II, or SBL-6669, are prevalent in West-Africa. In this study, we analysed the cross-reactivity at the protein level between HTLV-IV and HIV (HTLV-IIIB). The results indicate that most people infected with HTLV-IV have antibodies that react to the major gag protein of HIV p 24. There is also a high degree of immunologic cross-reactivity between the pol gene products of HIV and HTLV-IV. Among these the endonuclease/integrase is more conserved than the reverse transcriptase. In contrast, the envelope glycoproteins that are the most frequently detected antigens by antibodies from exposed individuals are serotype specific. These data make the env gene products the most interesting antigens for serotype specific diagnosis of human retroviruses infections.

Antibodies, Viral↗

[Treatment of peritonitis in kidney failure patients under continuous ambulatory peritoneal dialysis by pefloxacine. Results and pharmacokinetics].

Pefloxacin was used as monotherapy in 15 cases of peritonitis occurring in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Antibiotic administration was made intravenously on day 1 (800 mg) and from day 2 to day 4 (400 mg/day), then orally during 10 days (400 mg/day). The dosage of 400 mg gave a mean serum concentration peak (11.2 mg/l) and valley (5.4 mg/l) on the second day and a mean dialysate level of 5 mg/l. The last mean serum concentration (J14) were 5.5 mg/l (peak) and 2.5 mg/l (valley) and the mean dialysate level was 2.6 mg/l. Ten of these patients were cured. We explained pefloxacin therapy failure in two cases by resistant strains (S. sanguis and S. bovis), in one case by an acquired resistance during treatment (S. epidermidis), in an other case by catheter contamination; and in the last case, clinical failure occur despite good sensitivity with in vitro-test (Acinetobacter).

Adult↗

[Intraocular penetration of pefloxacin in man and rabbit. The aqueous humor and vitreous body].

Intraocular distribution of pefloxacin was evaluated in 64 patients undergoing ocular surgery and in 4 rabbits after experimental infection of one eye by Staphylococcus aureus. Patients were perfused during one hour either with 800 or 400 mg of pefloxacin. Samples (serum, aqueous humor, vitreous fluid) were collected 0, 1, 2, 3, 4, 5 or 12 h after the end of antibiotic administration. Antibiotic levels were measured using a standard microbiological assay. The aqueous humor levels remained stables until 12 h, but were higher with a posology of 800 mg (mean level: 2.66 mg/l) than with a posology of 400 mg (mean level: 0.66 mg/l). The ratio between vitreous and serum concentrations ranged from 8 at 12% with 400 mg and from 2 to 36% with perfusion of 800 mg. The efficacy of pefloxacin treatment is demonstrated in the experimental infection of rabbits eyes.

Adult↗

Comparative multicentre study of the immunogenicity of different hepatitis B vaccines in healthy volunteers.

In a comparative study of the immunogenicity of different hepatitis B vaccines, 339 healthy seronegative adults at three different centres were randomly allocated to receive either three doses of a yeast-derived vaccine at one of three different dose levels (10, 20, or 40 micrograms; SmithKline Biologicals) or one of two commercial plasma-derived vaccines at standard dose levels (5 micrograms, Institut Pasteur Production or 20 micrograms, Merck Sharp & Dohme). The subjects were inoculated intramuscularly in the deltoid region according to a 0, 1, and 6 month schedule. No severe or serious adverse reactions attributed to any of the vaccines were observed. One month after the third vaccine dose, seroconversion rates ranged from 95% to 100% in all groups with only 6 subjects failing to seroconvert. Although there were no statistically significant intra-centre differences in antibody levels, the Tours/Chateauroux groups generally attained higher antibody levels than those from Limoges for the same yeast-derived vaccine dose. This unexplained difference between centres was not found for the plasma-derived vaccines. Older subjects responded less well than younger ones and females attained higher antibody levels than did males. The yeast-derived vaccine is comparable to the two commercially available plasma-derived vaccines in terms of reactogenicity and immunogenicity.

Adult↗

Early detection of streptococcal group antigens in skin samples by latex particle agglutination.

The streptococcal group antigens (A to G) were researched in skin biopsy specimens by a latex agglutination technique using commercial (Slidex Streptokit bio-Mérieux and Streptex Wellcome) and experimental reagents. Twenty-seven patients with obvious cutaneous infections (12 cases of erysipelas, nine cases of cellulitis, and six cases of necrotizing fasciitis) and 27 age- and sex-matched controls were studied. Our preliminary data demonstrated the possibility of an early diagnosis of streptococcal cutaneous infections involving the deep dermis and/or hypodermis. We used a latex agglutination technique that is quite specific and gives a better sensitivity (0.63) than either conventional bacteriologic cultures on needle aspiration or skin biopsy specimens.

Adult↗

[Diffusion of fosfomycin into the human and rabbit eye (aqueous humor and vitreous body)].

The intraocular distribution of fosfomycin was studied in 32 patients undergoing cataract surgery and in 8 rabbits after experimental infection of one eye by Staphylococcus aureus. Concentrations found 1 to 6 hours after termination of a 4 g fosfomycin infusion ranged from 14 to 18.8 mg/l in the aqueous humor and 8 to 12.5 mg/l in the vitreous body. These levels are higher than the MICs for 80 to 90% of the bacteria responsible for endophthalmitis. In each rabbit, the fosfomycin concentration in the infected eye as compared to the healthy eye was increased 2.5 to 5--fold for the aqueous humor and 4.9 to 19.2--fold for the vitreous body. Fosfomycin, in association with a third generation cephalosporin (ceftriaxone) or one of the new quinolones (pefloxacin) can be recommended for the prevention or early treatment of endophthalmitis.

Adolescent↗

[Multicenter study of ofloxacin activity on bacteria isolated from a hospital environment].

Minimal inhibitory concentrations (MICs) of ofloxacin were evaluated by agar dilution for 1508 bacterial strains isolated in five hospitals. For Enterobacteriaceae sensitive to nalidixic acid, MICs ranged from 0.008 to 1 microgram/ml (mode MIC: 0.12); the different species of Enterobacteriaceae exhibited similar mode MICs (0.12) with the exception of E. coli (0.06-0.12), P. mirabilis (0.5) and Providencia (0.25). Among strains intermediate and resistant to nalidixic acid, most of which were Serratia, Providencia and Citrobacter, 41% had a MIC within the susceptibility range, while the others had a MIC of 2 to 8 micrograms/ml, or even 64 micrograms/ml in a few instances. Ofloxacin also exhibited satisfactory activity against P. aeruginosa, with MICs ranging from 0.25 to 16 micrograms/ml (mode MIC: 2) for 87% of strains, and A. calcoaceticus, with MICs from 0.25 to 2 micrograms/ml (mode MIC: 1). Haemophilus sp. (MIC: 0.008 to 0.06 microgram/ml; mode MIC: 0.03), Gonococci (mode MIC: 0.008), and Meningococci (mode MIC: 0.016) were very sensitive to ofloxacin. The spectrum of ofloxacin included Gram positive cocci: MICs of Staphylococci were 0.06 to 2 micrograms/ml (mode MIC: 0.5); Enterococci, other Streptococci and Pneumococci were less sensitive, with MICs of 2 to 4 micrograms/ml for the majority of strains. As for anaerobic bacteria, ofloxacin proved more active against Clostridium (0.5 to 2 micrograms/ml) than Bacteroides (0.5 to 16 micrograms/ml).

Bacteria↗

[Intraocular penetration of fosfomycin in man and rabbits].

The intraocular distribution of fosfomycin was studied in 32 patients undergoing cataract surgery and or vitrectomy and in 8 rabbits after experimental infection of one eye by Staphylococcus aureus. In subjects perfused with 4 g of fosfomycin, concentrations ranged from 14 to 18.8 mg/l in aqueous humour (AH) and from 8 to 12.5 mg/l in vitreous fluid (VF) between 1 and 6 hours after the end of the perfusion; these levels were higher than MICs for 80-90 per cent of bacteria found in endophthalmitis. In rabbits the concentration in infected eyes with respect to healthy eyes was found to be from 2.5 to 5 times in AH and from 4.9 to 19.2 times higher in VF. Therefore fosfomycin in association with third generation cephalosporins (ceftriaxone) or with new quinolones can be recommended in the prevention and early treatment of endophthalmitis.

Adolescent↗

[Evaluation of a new latex test for detecting human rotaviruses in feces].

We have sought the presence of rotavirus in 237 fecal samples. Three techniques were applied to each sample: ELISA, latex agglutination (LTX) with two reagents (Rotalex and SlidexRotaKit), and electron microscopy after negative staining. The specificity of ELISA and LTX is very good (more than 93.4 per cent), the sensitivity is decreasing from ELISA to SlidexRotaKit and Rotalex (respectively 83.6-74.5 and 67.3 per cent). The advantages of LTX include rapidity, simplicity, low cost price.

Adult↗

[Pharmacokinetics of vancomycin in chronic renal failure patients in continuous ambulatory peritoneal dialysis (CAPD) after intra-abdominal administration].

Peritonitis is one of the most serious complication concerning patients under continuous ambulatory peritoneal dialysis (CAPD). A Staphylococcus (aureus, epidermidis) is the causative pathogen in nearly 60% of cases. This prompted a study of vancomycin, a potent antistaphylococcal agent (MIC less than or equal to 3 micrograms/ml) in 13 patients with peritonitis. Vancomycin was used as single drug therapy. Kinetics were studied after a single injection of 1 g into the dialysate bag. Serum and peritoneal concentrations exceeding 3-4 micrograms/ml were found to persist for four days; half-life was 62.3 and 54.8 h in the dialysate and serum respectively. Peritoneum to serum diffusion varied widely across individuals. In 15% of patients, serum concentration exceeded the potentially ototoxic level (80 micrograms/ml) for a few hours.

Diffusion↗