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G Delage

Publications and source records attributed to G Delage.

At least 19 recordsLinked to original sources

Comparative immunogenicity under field conditions of two recombinant hepatitis B vaccines in 8-10-year-old children.

The immunogenicity of two hepatitis B vaccines was compared in 8-10-year-old children immunized in a school program. One year apart, 1129 children received Engerix-B 10 microg vaccine (EB), and 1126 received Recombivax-HB 2.5 microg (RB), following the 0, 1, 6 schedule. Blood samples were collected one month after the third dose. Anti-Hbs were measured by commercial radioimmunoassay. In the EB group, 99.1% of the children seroconverted (>/=2 IU/l) compared to 99.7% in the RHB group (p=0.09). The seroprotection rate (>/=10 IU/l) was similar for both groups: 98.9% in the EB group and 99.2% in the RB group (p=0.66). However, GMCs of anti-HBs were higher in children given EB compared to those given RB (7307 vs. 3800 mIU/ml, p<0.0001). This study showed that both vaccines were highly immunogenic, in the course of a regular field immunization program. However, the difference observed in the antibody levels attained according to the vaccine may play a role in the long-term protection of these children.

Child

Performance of a multiplex PCR for the determination of Haemophilus influenzae capsular types in the clinical microbiology laboratory.

To improve tools for the surveillance of invasive H. influenzae in the context of the drastic decrease of type b infections following the implementation of vaccination, a two-step PCR technique was developed to detect the capsule and type specific regions of H. influenzae. The technique of Falla et al (1994) was modified to amplify in a first step the capsule and type b regions by multiplex PCR. For non-b capsulated strains, the type a, c, d, e, and f loci were afterward detected simultaneously by an optimized touch-down PCR technique. An internal control of extraction and amplification (16S rDNA) was included for both PCR techniques. Overall, this technique was shown to perform as efficiently or better than the slide agglutination without risks of interpretation errors. Of the 138 H. influenzae strains tested, seven that had given doubtful results by the agglutination technique were unequivocally typed by PCR.

ATP-Binding Cassette Transporters

Risk factors for acquisition of hepatitis C virus infection in blood donors: results of a case-control study.

BACKGROUND & AIMS: Few studies have explored risk factors predicting hepatitis C virus (HCV) infection in blood donors; their results are contradictory. The aim of this study was to evaluate the association between HCV infection and various risk factors in Canadian volunteer blood donors. METHODS: Four transfusion centers were involved in this case-control study. A total of 267 confirmed anti-HCV-positive blood donors were interviewed along with 1068 seronegative blood donors matched for sex, age, donation site, and date. Information was collected using a structured telephone interview. The main outcome measures were odds ratios (ORs) and 95% confidence intervals (CIs) for various risk factors from univariate and multivariate analyses using conditional logistic regression. RESULTS: By univariate analysis, 23 variables were associated with anti-HCV positivity. In the final multivariate analysis, only 5 factors remained independently predictive of HCV infection: previous intravenous drug use (OR, 127.5; 95% CI, 26.0-625.0), having lived in a prison or juvenile detention center (56.1; 11.4-275.7), previous blood transfusion (10.5; 4.7-23.2), sexual contact with an intravenous drug user (6.9; 3.1-15.2), and tattooing (5.7; 2.5-13). CONCLUSIONS: Most blood donors acquire infection by percutaneous exposure to contaminated blood. A role for sexual transmission is suggested by this study.

Adult

Epidemiological features of pertussis in hospitalized patients in Canada, 1991-1997: report of the Immunization Monitoring Program--Active (IMPACT).

To assess the morbidity associated with the continued high levels of pertussis, we studied all children <2 years of age who were admitted to the 11 Immunization Monitoring Program--Active (IMPACT) centers, which constitute 85% of Canada's tertiary care pediatric beds. In the 7 years preceding implementation of acellular pertussis vaccine, a total of 1,082 pertussis cases were reported, of which 49.1% were culture-confirmed. The median age of the patients was 12.4 weeks; 78.9% of cases were in children <6 months of age. Complications of pertussis were common: pneumonia was reported in 9.4% of cases, new seizures in 2.3%, and encephalopathy in 0.5%. There were 10 deaths (0.9%), all in children < or =6 months of age. Duration of hospitalization was longer (9.3 days vs. 4.9 days; P = .001) and intensive care was required more frequently (19.2% vs. 4.9%; P = .001) in infants under <6 months of age than in those > or =6 months. Pertussis continues to cause significant morbidity and occasional mortality in Canada, particularly in young infants.

Canada

Evaluation of rubella screening in pregnant women.

BACKGROUND: The rationale for rubella vaccination in the general population and for screening for rubella in pregnant women is the prevention of congenital rubella syndrome. The objective of this study was to evaluate the effectiveness of the prenatal rubella screening program in Quebec. METHODS: A historical cross-sectional study was designed. Sixteen hospitals with obstetric services were randomly selected, 8 from among the 35 "large" hospitals in the province (500 or more live births/year) and 8 from among the 50 "small" hospitals (fewer than 500 live births/year). A total of 2551 women were randomly selected from all mothers of infants born between Apr. 1, 1993, and Mar. 31, 1994, by means of stratified 2-stage sampling. The proportions of women screened and vaccinated were ascertained from information obtained from the hospital chart, the physician's office and the patient. RESULTS: The overall (adjusted) screening rate was 94.0%. The rates were significantly different between large and small hospitals (94.4% v. 89.6%). Five large hospitals and one small hospital had rates above 95.0%. The likelihood of not having been screened was statistically significantly higher for women who had been pregnant previously than for women pregnant for the first time (4.8% v. 1.4%; p < 0.001). Of the 200 women who were seronegative at the time of screening (8.4%), 79 had been vaccinated postpartum, had a positive serological result on subsequent testing or did not require vaccination, and 59 had not been vaccinated postpartum; for 62, subsequent vaccination status was unknown. INTERPRETATION: Continued improvement in screening practices is needed, especially in small hospitals. Because vaccination rates are unacceptably low, it is crucial that steps be taken to address this issue.

Canada

Risk of HIV infection from blood transfusion in Montreal.

OBJECTIVES: To determine the incidence (including associated donor characteristics and time trends) of HIV infection among repeat blood donors and to estimate the risk of HIV transmission from blood transfusion in Montreal and in Canada as a whole. DESIGN: Retrospective cohort analysis. SETTING: Montreal Centre Blood Transfusion Service. PARTICIPANTS: People who donated blood at least twice after Nov. 1, 1985, and at least once from Apr. 1, 1989, to Mar. 31, 1993. INTERVENTION: Blood was screened for HIV by enzyme-linked immunosorbent assay and results were confirmed by Western blot analysis. OUTCOME MEASURES: Incidence density (the incidence rate per person-time) of HIV infection among repeat blood donors by sex, age group and region of residence, and incidence density and risk among first-time donors and for Canada as whole. RESULTS: There were 200,196 eligible donors and 432,631 person-years (PY) of observation. From 1989 to 1993, there were 18 HIV seroconversions among repeat donors. The crude incidence density was 3.3 per 100,000 PY (95% confidence interval [CI] 1.8 to 5.4 per 100,000 PY); it was 4.9 per 100,000 PY among men and 0.61 per 100,000 PY among women. Age-specific incidence per 100,000 PY was 2.5 among those 12-29 years of age, 5.1 among those 30-49, 2.9 among those 40-49, and 1.4 among those 50 and older. Based on an estimated mean "window period" (from when a donor's blood is capable of transmitting HIV until detectable antibody appears) of 25 days, the current risk of HIV infection from repeat donors in the window period is estimated at 1 in 440,000. Inclusion of blood units from first-time donors produces an overall risk of 1 in 390,000 (95% CI 1 in 250,000 to 655,000). The estimated risk per blood unit in Canada as a whole is 1 in 913000 (95% CI 1 in 507,000 to 2,050,000). CONCLUSIONS: This "sentinel" population of repeat blood donors is subject to important trends in HIV spread. Therefore, estimating the incidence density of HIV infection in repeat donors provides insight into the epidemiologic characteristics of HIV infection at minimal expense. As a result of measures to improve blood safety, including HIV testing, the incidence of HIV infection among blood donors in Canada is low and the risk of HIV transmission from transfusion is extremely small, although not zero.

Adolescent

Evaluation of donor skin disinfection methods.

BACKGROUND: Because most bacteria isolated from contaminated platelet concentrates are thought to originate from the donor's skin, the efficacy of four methods of skin disinfection was compared. STUDY DESIGN AND METHODS: Contact plates were used for antecubital skin cultures after they were demonstrated to be easier to use and at least as sensitive as a swab system. One antecubital fossa of each subject was disinfected by a standard method, the use of a povidone-iodine swabstick containing 0.75-percent available iodine followed by the use of a povidone-iodine swabstick containing 1-percent available iodine. The other arm was disinfected with either a 70-percent isopropyl alcohol scrub followed by an ampoule of 2-percent iodine tincture (Group 1; n = 126); a green-soap sponge followed by a 70-percent isopropyl alcohol swab, used for donors who are allergic to iodine (Group 2; n = 30); or a 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol sponge followed by an ampoule of 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol (Group 3; n = 40). Contact plate cultures were done before and after disinfection, and colonies counted after a 48-hour 37 degrees C incubation period. RESULTS: Similar numbers of bacteria grew from both antecubital fossae of the same subject before disinfection (p = 0.71). Compared to the standard povidoneiodine method, isopropyl alcohol and tincture of iodine resulted in significantly less bacterial growth (p < 0.001), the green soap and isopropyl alcohol method resulted in significantly more bacterial growth (p < 0.001), and the chlorhexidine gluconate and isopropyl alcohol method resulted in similar amounts of bacterial growth (p > 0.3). CONCLUSION: Isopropyl alcohol scrub followed by iodine tincture is more efficacious than povidone-iodine as measured by contact plate cultures. For donors who are allergic to iodine, chlorhexidine gluconate and isopropyl alcohol is more efficacious than green soap and isopropyl alcohol.

1-Propanol

Immune suppression and Th1/Th2 balance in pregnancy revisited: a (very) personal tribute to Tom Wegmann.

PROBLEM: The paradigm of local suppression necessary to understand the survival of the fetal allograft is often compared with the host-tumor relationship. METHODS: We investigated two components of local immune suppression: placenta-induced immunosuppression, which is mediated at least in part by a soluble factor of low molecular weight that can induce anergy in lymphocytes, and interleukin-10 (IL-10). RESULTS: We show that enhancement of IL-10 production in the decidua and placenta after alloimmunization requires the presence of Asialo GM1+ cells. Placenta-induced immunosuppression is linked with defects in phosphorylation of some components of the T cell receptor. CONCLUSION: NK cells could be in fact regulatory cells pushing maternal immune response toward a Th2 profile, beneficial for fetal survival, or toward a Th1 type of immune response, which acts in synergy. Modulation of TcR may represent a new mechanism for maternal-fetal tolerance.

Animals

[Tumor necrosis factor and induced labor].

TNF and LPS can induced labour in mice. In our serial, in induced RU 486 labour, TNF value enhanced 48 hours after RU 486 and decreased after parturition.

Abortifacient Agents, Steroidal

Epstein-Barr virus transmission from a blood donor to an organ transplant recipient with recovery of the same virus strain from the recipient's blood and oropharynx.

A previous study (Savoie et al, Blood 83:2715, 1994) identified eight transplant patients who acquired Epstein-Barr virus (EBV) infection during the peritransplant period. Three of these patients subsequently developed B-cell lymphoproliferative disease within 4 months of transplantation. Among these, there was a 16-year-old liver transplant patient who was negative for EBV at the time of transplant and who received an EBV-negative organ. After transplant, this patient was transfused with 9 U of packed red blood cells. Eight of the donors were EBV-positive and one was EBV-negative. We succeeded in obtaining spontaneous lymphoblastoid cell lines (LCLs) from the blood of three of these donors, one of whom also yielded a cord-blood line established with his throat-wash EBV. Blood from a fourth donor did not yield an LCL, but his throat washing did have transforming activity when inoculated onto cord-blood leukocytes. We initially could establish spontaneous LCLs only from the recipient's blood. However, a throat-wash sample taken 11 weeks later did show transforming activity. The recipient was shown to have acquired the EBV infection from one of eight EBV-seropositive blood donors. Analysis of fragment length polymorphisms after polymerase chain reaction amplification of the EBV BamHI-K fragment was used to establish strain identity. Western blot analysis for existence of size polymorphisms in three classes of Epstein-Barr nuclear antigens (EBNA-1, EBNA-2, and EBNA-3) confirmed the DNA results. It is noteworthy that the blood donor responsible for transmitting his EBV strain to the recipient had experienced clinical infectious mononucleosis 15 months before donating blood. Our results may, thus, indicate a requirement for leukodepletion of blood destined for immunosuppressed EBV-negative patients. Finally, blood donors with a recent history of infectious mononucleosis should probably be identified so that their blood is not given to EBV-negative transplant patients.

Adolescent

Biological and clinicopathological features associated with hepatitis C virus type 5 infections.

BACKGROUND/AIMS: The biological and clinicopathological features of hepatitis C virus infections of type 1 and type 2 have been well documented. However, little is known about the nature of HCV type 5 infections, which have been found to occur in South Africa but rarely elsewhere. METHODS: We investigated the HCV genotypes in 125 viremic blood donors and 125 viremic patients by restriction endonuclease analysis of amplified 5' non-coding region sequences. Donors and patients infected with type 5 were further studied. Serum HCV RNA levels were assessed by a differential-size PCR-aided transcript titration assay. RESULTS: HCV type 5 infections were identified in seven (5.6%) of the blood donors and in five (4.0%) of the patients. Sera from these 12 persons reacted with the core and NS3 antigens in both RIBA-2 and RIBA-3 tests. Six (50%) and 10 (83%) sera reacted with the NS4 antigens in RIBA-2 and RIBA-3 tests, respectively. HCV type 5 was found to replicate to high titers that ranged from 10(6.0) to 10(8.0) molecules/ml. Transfusion was the most frequently observed risk factor (5 of 12) and persons infected with type 5 were generally older than those infected with other types (< 40 years vs. > or = 40 years, p = 0.01). Cirrhosis was found in two of six (33%) donors and three of four (75%) patients. The duration of infection appeared to be an important determinant for the presence of cirrhosis. CONCLUSIONS: In this small group of Canadians infected with HCV type 5, a high proportion developed severe liver disease.

Adult

Identification of numerous hepatitis C virus genotypes in Montreal, Canada.

Hepatitis C virus genotypes were determined for 358 viremic individuals in Montreal, Canada, by restriction endonuclease analysis of PCR products and phylogenetic analysis of core gene sequences. Types 1, 2, and 3 occurred in 62.8, 14.2, and 13.7%, respectively; types 4 and 5 were found in 3.9 and 4.5%, respectively; and genotypes 6a and 7c and a novel genotype each occurred in 0.3%. Types 4, 6, and 7 and the novel genotype were mostly from persons who had immigrated to Canada.

Adult

Immuno-endocrine interactions in early pregnancy.

First we recall briefly the status of inflammatory cytokines in the early implantation period. We then describe the status of leukaemia inhibiting factor (LIF) production in an in-vitro, relatively short-term, human decidual explant culture system. We show that in most infertile women with recurrent implantation failure following successful in-vitro fertilization, LIF production is statistically much lower than normal. Other parameters of LIF production in vitro are summarized briefly, and the effects of RU486 are shown. The TH2 status of normal pregnancy is described, together with the production of TH2 cytokines by decidua and placenta. These cytokines are deficient in the CBAXDBA/2 model of murine spontaneous early pregnancy loss. The defect can be corrected by alloimmunization, and more importantly by the injection of tau interferon. The significance of these data for early pregnancy signalling is discussed.

Animals

In-vitro endometrial secretion of human interleukin for DA cells/leukaemia inhibitory factor by explant cultures from fertile and infertile women.

Human interleukin for DA cells/leukaemia inhibitory factor (HILDA/LIF) is a cytokine with pleiotropic effects involved in successful murine implantation. We evaluated human uterine HILDA/LIF production by monitoring its in-vitro secretion by endometrial explant cultures obtained from individuals in either normal or pathological conditions. The cytokine secretion was standardized using the day 5:day 1 ratio of HILDA/LIF concentration in supernatants of such cultures, hereby termed HILDA/LIF production index (HLPI). Our results confirmed that HILDA/LIF is secreted by the human endometrium as assessed by secretion at every phase of the cycle in either normal fertile women, or women bearing intrauterine devices. This was also the case for samples obtained from infertile women presenting repeated failures of embryonic implantation or unexplained primary sterility. However, the HLPI were significantly lower in those latter two groups when compared to fertile women. These results suggest an abnormal regulation of HILDA/LIF secretion in such circumstances, and the clinical implication of those data is discussed.

Adult