Search PubMed⌕ Search

Biomedical subjects

C Blondeau

Publications and source records attributed to C Blondeau.

35 records · Page 2Linked to original sources
PubMed1998

Antibody persistence following preexposure regimens of cell-culture rabies vaccines: 10-year follow-up and proposal for a new booster policy.

Subjects (n = 312) received either the human diploid cell rabies vaccine (HDCV) or the purified Vero cell rabies vaccine (PVRV) according to either two-injection (days 0 and 28) or three-injection (days 0, 7, and 28) primary regimens. They received a booster injection at 1 year. Rabies antibody levels were measured after the primary series and the booster and then each year for the next 10 years. The results confirm the superior long-term immunogenicity of the three-injection over the two-injection protocol. HDCV and PVRV in three doses were equally immunogenic. A booster injection at 1 year provides long-term seroconversion (titer > or = 0.5 IU/mL). Antibody titers 2 weeks after the 1-year booster allowed prediction of long-term immunity. Good responders, with titers > or = 30 IU/mL, were protected for at least 10 years. An algorithm for differentiation between good responders and poor responders with respect to vaccine booster strategies is proposed.

Adolescent↗
PubMed1998

Clinical acceptability and immunogenicity of a pentavalent parenteral combination vaccine containing diphtheria, tetanus, acellular pertussis, inactivated poliomyelitis and Haemophilus influenzae type b conjugate antigens in two-, four- and six-month-old Chilean infants.

BACKGROUND: In recent years additional parenteral vaccines have been recommended for routine immunization of infants in the US and elsewhere. The ability to administer multiple vaccines as a single injection without unacceptably increasing reactogenicity or decreasing immunogenicity of any component would offer many practical advantages. METHODS: A randomized, open, controlled trial was conducted to assess the tolerance profile and immunogenicity, as well as to identify potential antigenic interferences, resulting from administration of a parenteral combination vaccine for infants. The vaccine contains diphtheria and tetanus toxoids, acellular pertussis antigens (DTaP), enhanced inactivated poliovirus (eIPV) and Haemophilus influenzae type b-tetanus toxoid conjugate (PRP-T). Infants (n=711) were randomly assigned to receive 1 of 5 regimens as the primary series at 2, 4 and 6 months of age, by group: (1) DTaP plus oral polio vaccine (OPV); (2) DTaP plus eIPV (separate injections); (3) DTaP-eIPV combined as a single injection; (4) DTaP-eIPV combined, plus a separate injection of PRP-T; or (5) DTaP-eIPV combined and reconstituting PRP-T, as a single injection. At 3, 5 and 7 months Groups 1, 2 and 3 received PRP-T. At 12 months all infants received a booster dose of DTaP reconstituting PRP-T as a single injection, plus a separate injection of measles, mumps and rubella vaccine. Groups 2, 3, 4 and 5 received OPV at 7 months, and all infants received OPV at 13 months. Serum immune responses were measured to the primary series at 2 and 7 months and to the booster dose at 12 and 13 months. RESULTS: Reaction rates were similar among groups. In the primary series combining eIPV with DTaP decreased geometric mean titers (GMTs) to diphtheria, tetanus and pertussis. In addition concomitant PRP-T (either simultaneous or combined) with DTaP-eIPV lowered anti-PRP and further decreased tetanus GMTs. Nonetheless in 100% of infants protective titers were achieved against diphtheria and tetanus (>0.01 IU/ml each) and against the poliovirus types 1, 2 and 3 after eIPV (Groups 2 to 5); 99% of infants (Groups 4 and 5) had protective titers against PRP (> or = 0.15 microg/ml). After boosting with DTaP/PRP-T decreased GMTs to diphtheria and PRP antigens were observed in the groups that received DTaP and eIPV combined. Nonetheless protective titers to diphtheria, tetanus and PRP occurred consistently. In contrast concomitant PRP-T with DTaP-eIPV enhanced the pertussis GMTs. CONCLUSIONS: We conclude that combined DTaP, eIPV and PRP-T in a single injection is well-tolerated and elicits an acceptable immune response to each component.

Adhesins, Bacterial↗
PubMed1998

Safety and immunogenicity of a combined diphtheria-tetanus-acellular pertussis-inactivated polio vaccine-Haemophilus influenzae type b vaccine administered at 2-4-6-13 or 3-5-12 months of age.

METHODS: In an open randomized study we compared the safety and immunogenicity of two schedules for priming and booster vaccinations of infants. A pentavalent combination vaccine, including a lyophilized Haemophilus influenzae type b-tetanus toxoid conjugate vaccine reconstituted with a liquid diphtheria, tetanus, acellular pertussis (pertussis toxoid and filamentous hemagglutinin) and inactivated polio vaccine (DTaP-IPV/Act-HIB; Pasteur Mérieux Connaught, Lyon, France) was administered to 236 Swedish infants either at 2, 4 and 6 months or at 3 and 5 months, and a booster dose was administered 7 months after the last primary dose. Adverse events were monitored by diaries for 3 days after each vaccination and by questions at the ensuing visits. Antibodies against the different vaccine components were analyzed after the primary series of vaccinations, before and after the booster injections. RESULTS: There were no serious adverse reactions, and the rates of febrile events and local reactions were low in both groups. The three dose primary schedule induced higher geometricmean concentrations for all antigens than did the two dose schedule, but there were no differences between the groups in proportions with protective antibody titers against diphtheria, tetanus, Hib and polio or in proportions with certain defined levels of pertussis antibodies. Prebooster results showed a similar pattern, with the exception that the group primed with three injections showed higher proportions of infants with detectable antibodies against polio-virus types 1 and 3. After booster vaccinations there were no differences between the two schedules in geometric mean or in proportions with antibodies above defined antibody concentrations, indicating effective priming from both primary series of vaccinations. Conclusion. The combined vaccine DTaP-IPV/ Act-HIB vaccine was equally safe and immunogenic when administered according to both time schedules studied.

Antibodies, Bacterial↗
PubMed1997

Challenge of chimpanzees immunized with a recombinant canarypox-HIV-1 virus.

To evaluate the potential protective efficacy of a live recombinant human immunodeficiency virus type 1 (HIV-1) canarypox vaccine candidate, two chimpanzees were immunized five times with ALVAC-HIV-1 vCP250, a recombinant canarypox virus that expresses the HIV-1[IIIB(LAI)] gp120/TM, gag, and protease gene products. One month after the last booster inoculation, the animals were challenged by intravenous injection of cell-associated virus in the form of peripheral blood mononuclear cells from an HIV-1[IIIB(LAI)]-infected chimpanzee. One chimpanzee with a neutralizing antibody titer to HIV-1[IIIB(LAI)] of 128 at the time of challenge was protected, whereas both the second animal, with a neutralizing antibody titer of 32, and a naive control animal became infected. At 5 months after challenge, the protected chimpanzee and a third animal, previously immunized with various HIV-1[MN] antigens, were given a booster inoculation. The two animals were challenged intravenously 5 weeks later with twenty 50% tissue culture infectious doses of cell-free HIV-1[DH12], a heterologous subtype B isolate. Neither chimpanzee had neutralizing antibodies to HIV-1[DH12], and neither one was protected from infection with this isolate. The immune responses elicited by vaccination against HIV-1[IIIB(LAI)] or HIV-1[MN] did not, therefore, protect the animals from challenge with the heterologous cell-free HIV-1[DH12].

AIDS Vaccines↗
PubMed1997

Normal and pathological changes in alpha rhythms.

Normal alpha rhythm begins to appear at three months. It was possible to observe successively, the rhythmicity, visual reactivity, occipital topography, and at the end of the first year, the first bursts of 7-8 Hz waves. Evolution of alpha was not linear with the age. Alpha frequency acceleration was important before the age of 11 years. In adults it decreased from 20 to 55, then there was a tendency to increase with aging. Amplitude was highest at 11-12 years, then its tendency was to decrease until 40, and to increase later. In pathology, for instance, alpha could be observed too early in newborn and infants with malformations, in children, in some psychiatric diseases, in adults and old people, alpha was replaced by theta waves in dementia: it seemed to be a very reliable sign, at the beginning of the disease.

Adolescent↗
PubMed1996

Analysis of the antibody response in humans with a new inactivated hepatitis A vaccine.

Sera from subjects vaccinated with the Pasteur Merieux (PM) inactivated hepatitis A vaccine (AVAXIM) have been analysed in order: (1) to assess comparability of the results provided by a modified radio-immunoassay (mRIA) in the different laboratories involved in testings of sera during clinical trials and by enzyme-linked immunoabsorbent assay (ELISA) used during development of other inactivated hepatitis A vaccines; (2) to describe the IgM responses elicited by this vaccine compared with one control vaccine [HAVRIX, 720 ELISA antigens units; Smithkline Beecham (SB), Rixensart, Belgium]; (3) to provide comparative data between the PM vaccine and the SB vaccine on neutralizing activities of vaccine-induced antibodies. Vaccine-induced antibody titres evaluated by a mRIA in different laboratories correlated well and validated the comparability of the results obtained in various vaccine trials conducted by PM. Geometric mean titres (GMTs) expressed as milli-international units (mlU/ml) were higher with ELISA especially after the first dose, but seroconversion rates were similar and a good correlation was found between the two assays. IgM vaccine-induced antibodies were detectable in nearly all vaccinated subjects from week 2 after vaccination, with a peak titre between weeks 2 and 4 after the first dose. Comparison of GMTs by the Student Fisher t-test was statistically significant (P < 0.05) only at week 2 with higher titres in PM vaccinees. Neutralizing antibodies were detected after vaccination with the PM inactivated hepatitis A vaccine. The titres gradually increased between the second week after the first dose and the booster dose (week 24). A strong booster effect of the second dose on neutralizing titres was observed. Seroneutralizing titres induced at week 2 in subjects vaccinated with the PM inactivated hepatitis A vaccine were statistically significantly higher (P < 0.05) from those induced by the SB vaccine.

Adolescent↗
PubMed1996

Combined diphtheria, tetanus, pertussis, and Haemophilus influenzae type b vaccines for primary immunisation.

A total of 146 infants were immunised at ages 2, 3, and 4 months with a combined diphtheria, tetanus, pertussis (DTP)--Haemophilus influenzae type b (Hib) tetanus toxoid conjugate (PRP-T) vaccine (Pasteur Merieux) to assess the antibody response and adverse events associated with immunisation. Adverse events, including fever, were recorded by parents in a diary for three days following each injection. Blood was taken before the first immunisation and four weeks after the third immunisation to assess antibody response. Data were compared with those from historical controls who had received DTP and PRP-T vaccines by separate injection. The combined vaccine was well tolerated. Rates of local and general reactions were similar to those reported for infants immunised by separate injection. All infants achieved protective antibody titres (> 0.01 IU/ml) for diphtheria and tetanus; 98% acquired Hib (PRP) antibody > 0.15 microgram/ml and 82.5% > 1.0 microgram/ml. Pertussis antibody titres (pertussis toxin, filamentous haemagglutinin, total agglutinins, and agglutinins 2 and 3) showed appreciable rise following immunisation. DTP and PRP-T vaccines provide similar antibody responses and adverse effects whether mixed in the same syringe or administered by separate injection. The vaccines could be combined for use in the United Kingdom primary immunisation schedule.

Antibody Formation↗
PubMed1995

Simultaneous injection of plasma-derived or recombinant hepatitis B vaccines with yellow fever and killed polio vaccines.

Previous studies have shown an absence of interaction between hepatitis B (HB) vaccine and other vaccines used in EPI programmes except for an apparent decrease of yellow fever antibody levels when hepatitis B and yellow fever vaccines are given simultaneously. We have therefore reinvestigated the interaction of these two vaccines and assessed the absence of interaction between inactivated polio vaccine and recombinant or plasma-derived HB vaccine. The immune responses to polio vaccine injected simultaneously with plasma-derived or recombinant HB vaccine were observed to be equivalent and similar to those observed in the literature. In this randomized study, the immune responses to yellow fever injected simultaneously with plasma-derived or recombinant HB vaccine were comparable to those observed after separate administration of each vaccine. Moreover, no increase in adverse reactions was noted.

Female↗
PubMed1992

Comparative immunogenicity in children of mammalian cell-derived recombinant hepatitis B vaccine and plasma-derived hepatitis B vaccine.

Three doses of hepatitis B vaccine were given at 2, 4 and 9 months of age to 220 Senegalese infants living in the Dakar area of Senegal. Half of the infants received 5 micrograms plasma-derived hepatitis B vaccine (Hevac B) and the remainder 20 micrograms mammalian cell-derived recombinant hepatitis B vaccine (GenHevac B). Both vaccines contain S and pre-S2 encoded proteins; however, the recombinant vaccine had a much higher pre-S2 content than the plasma-derived vaccine. Adverse reactions to both vaccines were limited to mild and transient soreness at the injection site. Fever was reported in 14-21% of the infants and was likely to be related to DTP-polio vaccine which was given simultaneously. After the two first doses, seroconversion rates and geometric mean titres of anti-HBs were higher in infants receiving the recombinant vaccine than in infants receiving the plasma-derived vaccine. After completion of vaccination, all infants in both groups had protective levels of anti-HBs antibodies. The recombinant vaccine induced more rapidly antibodies directed against S and pre-S2 epitopes. Anti-pre-S2 antibodies were detected after the first injection of GenHevac B and only after the third injection of Hevac B. From the data, GenHevac B vaccine is expected to be as effective as Hevac B vaccine for controlling hepatitis B infection.

Amino Acid Sequence↗
PubMed1987

[Platelet antioxidant enzyme activities in arteriopathy].

Some publications have pointed out that oxygen free radicals can induce injury of vessel wall and increase platelet aggregation and clotting, which can suppose a dependent relationship with arteriosclerotic process. We therefore studied the hypothesis of a possible abnormal platelet antioxidant enzymatic equipment in arteriopathic patients. A control group of 20 healthy subjects and an other one of 40 non diabetic patients with peripheral arterial disease were investigated, and the following tests were performed: measure of transcutaneous oxygen tension (PTCO2), determination of activity of platelet superoxide dismutase (SOD), glutathione-peroxidase (G-Px) and catalase (CAT). A significant decrease of SOD and G-Px is observed in platelets of arteriopathic patients. This decrease seems to be correlated with the severity of ischemia. The pathological reduction of platelet antioxidant equipment can be one factor enhancing thrombotic complications in chronic arterial disease.

Arteritis↗
PubMed1982

[Electroencephalographic surveillance during carotid endarterectomy].

Continuous EEG monitoring during 110 carotid endarterectomies showed transient or permanent abnormalities in 35 cases. In 13 cases, these abnormalities occurred during carotid clamping and led the surgeon to place a shunt in 8 cases. In 22 cases, electrical abnormalities of various types appeared outside the clamping period. Continuous EEG monitoring demonstrated that cerebral disturbances can occur at any time during the operative period. Thus, intra-operative EEG monitoring allows a better understanding of clinical signs which may be seen postoperatively.

Anesthesia, General↗
PubMedDate not supplied

Safety and immunogenicity of a new equine tetanus immunoglobulin associated with tetanus-diphtheria vaccine.

In a single-center double-blind, randomized trial in West Africa, we evaluated the safety and immunogenicity of a new pasteurized, pepsin-digested equine tetanus immunoglobulin (heat-treated equine tetanus immunoglobulin [HT-ETIG]) in the post-exposure prophylaxis of tetanus compared with the reference product, equine tetanus immunoglobulin (ETIG). A total of 134 adults presenting to Garoua Hospital, Cameroon with a tetanus-prone wound were randomized to receive a 3,000 international units (IU) intramuscular injection (deltoid) of either HT-ETIG or ETIG, simultaneously with a tetanus-diphtheria vaccine. No serious adverse reactions were reported. The incidences of local and systemic reactions were similar in the two groups. Repeated measures of equine tetanus-antibody levels measured from Day 0 to Day 28 showed that titers were significantly higher in the HT-ETIG group (P = 0.017). At Day 7, a higher percentage of subjects in the HT-ETIG group had equine antibody levels > or = 0.1 IU/ml (80.4% versus 37.9%; P < 0.0001). No cases of tetanus occurred during the follow-up, attesting to the efficacy of the combined prophylactic treatment.

Adolescent↗
PubMedDate not supplied

[Control of hepatitis B in French Polynesia with a program of systematic vaccination of newborns with the Genhevac B vaccine].

In 1988, a 5-year vaccination program against hepatitis B was launched for all newborns in a pilot area, the Austral archipelago in French Polynesia. Genhevac B, a recombinant vaccine produced from mammalian cells was administered. Three different immunization schedules were used, none of them including additional specific immunoglobulin: i) four doses, one at each months (M) 0, 1, 2, and 12; ii) three doses one at each MO, M1 and M6; and iii) three doses one at each MO, M1 and M12. Each year during the 5 year period a serological survey was conducted. Of the 837 children who received at least one vaccine dose, 5 were HBsAg carriers. Seroprotection rates for anti-HBs and anti-PreS2 antibodies were 88% after one dose and 97% after two doses. After the third dose, seroprotection rates and geometric mean titers of anti-HBs antibodies were 95% and 217 mIU/ml for schedule (i) (three dose only); 92% and 389 mIU/ml for schedule (ii) and 93% and 344 mIU/ml for schedule (iii) respectively. After four doses (schedule i) the values were 100% and 1228 mIU/ml. Of the 18 newborns whose mothers were positive for both HBsAg and HBeAg, one was a HBsAg carrier. The estimated protective rate for prevention of perinatal transmission was 94%. This study suggests that in field conditions, systematic vaccination of newborns without using specific immunoglobulins can confer early protection. The schedule recommended for use in French Polynesia was three doses, at MO, M1 and M6-12 (between 6 and 12 months) with an additional booster dose at age 6 years, the last year of nursery school. Since April 1992, all children born in French Polynesia have been vaccinated according to this schedule. A catch-up program has been implemented for children aged 4 to 10 years old using a similar immunization schedule.

Child↗