Comparative long term immunogenicity of two recombinant hepatitis B vaccines and the effect of a booster dose given after five years in a low endemicity country

BACKGROUND: Few data are available concerning the long term immunogenicity of the pediatric doses of hepatitis B vaccines given to preteenagers. The long term effect of the booster dose in teenagers is unknown. We evaluated the immunogenicity of 2 pediatric hepatitis vaccines after primary vaccination and after a booster dose. METHODS: A prospective 15-year follow-up study of the immunogenicity of 2 hepatitis B vaccines was initiated in 1995 in Quebec City, Canada. One year apart, 1129 children 8-10 years old received Engerix-B 10 microg (EB), and 1126 received Recombivax-HB 2.5 microg (RB) vaccine after a 0-, 1-, 6-month schedule. After 5 years, one-third of the 2 cohorts were randomly selected. A booster dose of EB 10 microg or RB 5 microg was administered according to the vaccine used in the primary immunization. Antibodies were measured before, 1 month after and 1 year after the booster injection. RESULTS: Before the booster dose, anti-HB surface antibody (HBs) was detected in 94.7% of the EB subjects and in 95.2% of the RB subjects (P = 0.85). The geometric mean titer (GMT) was higher in the EB than in the RB group (252 mIU/mL versus 66 mIU/mL, P < 0.0001). One month after the booster, 99.7% of subjects in the EB group and 99.6% in the RB group had a detectable anti-HBs, and 99.0 and 99.3%, respectively, had anti-HBs > or =10 mIU/mL. The anti-HBs GMT was 113,201 mIU/mL in the EB and 16,623 mIU/mL in the RB groups (P < 0.0001). One year after the booster, 99.3% of subjects in the EB group and 100% in the RB group had detectable anti-HBs, and 97.9 and 98.5% respectively, had anti-HBs > or =10 mIU/mL. The anti-HBs GMT was 14,028 mIU/mL in the EB and 3437 mIU/mL in the RB group (P < 0.0001). CONCLUSIONS: The immunity persists for at least 5 years after the primary vaccination with both pediatric vaccines in 99% of children vaccinated at the age of 8-10 years. It confirms that no booster is needed at that point.     

Nationwide canadian study of hepatitis a antibody prevalence among children eight to thirteen years old

BACKGROUND: Hepatitis A vaccines provide consistent, long-lasting protection and have been available for almost 10 years in Canada, but their use remains limited. It is difficult to assess their optimal utilization given that our knowledge of hepatitis A epidemiology in Canada is fragmentary. Unlike the United States, no nationwide study of hepatitis A prevalence has ever been done in Canada. Consequently we do not know the incidence of infection in children and what would be the most appropriate age for hepatitis A vaccination. OBJECTIVE: To estimate the proportion of 8- to 13-year-old children who have been infected with hepatitis A virus (HAV) and the risk factors for this infection on a nationwide scale. METHODS: Children were sampled in 10 Canadian provinces, comprising 5 regions, using random digit dialing methodology with regional stratification. Demographic data and information about risk factors for hepatitis A were collected by the telephone interviewers. Oral fluid samples were self-collected and mailed to the laboratory, where they were tested for anti-HAV IgG. RESULTS: Of 6740 contacted families with a child of required age, 1688 (25%) agreed to participate and answered the questionnaire. From these, 1074 oral fluid samples were received, and 1057 could be analyzed. Anti-HAV IgG was detected in 2.7% of subjects, with variation by region from 0.8 to 3.4%. The parents of 54 subjects (5.1%) reported that their child had previously been vaccinated against HAV. Anti-HAV IgG was present in 2.0% of unvaccinated subjects, among whom antibody prevalence was 19.4% in children born in HAV-endemic countries, 6.1% in Native children and 4.2% in travelers to endemic countries. In multivariate analysis of all subjects, the presence of anti-HAV IgG was significantly associated with birth in an endemic country, travel to an endemic country, Native status (American Indian and Inuit population), female gender and vaccination against HAV. In nonvaccinated, non-Native children born in Canada who did not travel to endemic countries, anti-HAV prevalence was 1.1%. CONCLUSIONS: The risk for hepatitis A during childhood is low in Canada. Almost all teenagers (>97%) would be at risk for infection in case of contact with HAV. Changes in immunization policy against hepatitis A should be considered.     

Effectiveness of intensive rehabilitation on functional ability and quality of life after first total knee arthroplasty: A single-blind randomized controlled trial

OBJECTIVE: To evaluate the effectiveness of a new intensive functional rehabilitation (IFR) program on functional ability and quality of life (QOL) in persons who underwent a first total knee arthroplasty (TKA). DESIGN: Randomized controlled trial. SETTING: Ambulatory care. PARTICIPANTS: Seventy-seven people with knee osteoarthritis. INTERVENTION: Two months after TKA, subjects were randomly assigned to either a group with IFR (n=38), who received 12 supervised rehabilitation sessions combined with exercises at home between months 2 and 4 after TKA, or to a control group (n=39), who received standard care. All participants were evaluated by a blind evaluator at baseline (2mo after TKA), immediately after IFR (2mo later; POST1), and 2 and 8 months later (POST2 and POST3).Main outcome measures The primary outcome measure with respect to effectiveness was the 6-minute walk test (6MWT) at POST2. Secondary outcome measures were the 6MWT at the other evaluations and the Western Ontario and McMaster Universities Osteoarthritis Index and Medical Outcomes Study 36-Item Short-Form Health Survey. RESULTS: Subjects in the IFR group walked longer distances (range, 23-26m) in 6 minutes at the 3 POST evaluations than subjects in the control group. At POST1 and POST2, they also had less pain, stiffness, and difficulty in performing daily activities. Positive changes in QOL in favor of the IFR were found only at POST2. CONCLUSIONS: The IFR was effective in improving the short-term and mid-term functional ability after uncomplicated primary TKA. The magnitude of the IFR effect on the primary outcome was modest but consistent. More intensive rehabilitation should be promoted in the subacute recovery period after TKA, to optimize functional outcomes in the first year after surgery.     

Identification of factors promoting abstinence from smoking in a cohort of elementary schoolchildren

BACKGROUND: Despite the progress made in smoking prevention among youth, few scientific reports have identified the determinants underlying the abstinence from cigarettes, and even fewer have made an assessment of their evolution over time. It has been proposed that this could be done by modeling after theoretical frameworks. METHODS: A self-reported questionnaire developed according to Ajzen's Theory of Planned Behavior was repeatedly administered to a cohort of 373 grade 5 students (191 girls and 182 boys) during their transition from elementary to secondary school. Four measures spanning a 26-month period were thus obtained and analyzed according to the GEE method. RESULTS: After 26 months, 76.14% of the students in the sample remained abstinent from cigarettes. The perceived smoking behaviors of friends and of a brother, intention over time, perceived self-efficacy, parental supervision, and socioeconomic status predicted the maintenance of abstinence from smoking. The final predictive model had a sensitivity of 79.8% and a specificity of 75.6%, with an average rate of accurate classification of 79.1%. CONCLUSIONS: The predictive model yielded by this study represents an important step toward developing tools to help 10-12 years olds maintaining their abstinent behavior. It emphasizes positive protective factors and guides health promoters in the choice of their interventions' contents and targets.     

Psychosocial determinants of the intention of nurses and dietitians to recommend breastfeeding

OBJECTIVES: To identify the major psychosocial determinants of the intention of nurses and dietitians to recommend breastfeeding to new mothers for six months as well as the salient beliefs underlying this intention. METHOD: Following an open-ended questionnaire that sought to elicit their most significant beliefs, a standardized questionnaire based on a modified model of Ajzen's theory of planned behaviour, was sent to New Brunswick nurses and dietitians who graduated between January 1992 and December 1996. Multiple regression analysis determined which variables contributed the most to the prediction of intention. RESULTS: The main determinants of intention were perceived behavioural control and perceived professional norm. They explained 69% of the variance in intention. All salient beliefs underlying the perceived behavioural control were significantly associated with intention. CONCLUSION: To help nurses and dietitians to support and promote breastfeeding more effectively, programs should focus on changing perceived and true barriers to recommending breastfeeding, as well as the related perceived professional norm.     

Activation of latent transforming growth factor beta 1 and inhibition of matrix metalloprotease activity by a thrombospondin-like tripeptide linked to elaidic acid

Impaired wound healing and skin aging are characterized by neutral protease-mediated destruction of matrix macromolecules associated with disturbance in tissue repair. We synthesized a fatty acyl-peptide derivative at aims to simultaneously activate latent TGF-beta through its peptide domain, KFK, and inhibit MMPs through its lipophilic moiety, elaidic acid. Elaidyl-KFK as well as KFK were shown to activate LAP-TGF-beta both in vitro, using a solid phase assay with immobilized LAP-TGF-beta, and ex vivo using human dermal fibroblasts cultures. In both assays, as much as up to 10% of LAP-TGF-beta added could be recovered as active form. KQK, KQFK as well as their lipopeptide counterparts were inactive. Elaidyl-KFK-mediated LAP-TGF-beta activation led to up-regulation of collagen and TIMP-1 production and down regulation of PMA-induced MMP-1 expression in fibroblasts cultures. Those effects could be suppressed by supplementing cell culture medium with blocking TGF-beta antibody. Elaidyl-KFK inhibited MMP-2, MMP-9, MMP-3, MMP-1, in vitro with IC(50) equal to 1.2, 1.0, 0.24 and 8.9 microM, respectively. Its ex vivo inhibitory capacity, as assessed using skin tissue sections, towards the elastin-degrading capacity of MMP-9 was even more pronounced. At a 1 microM concentration, the lipopeptide decreased by up to 80% enzyme activity. Thus, "Lipospondin," i.e. elaidyl-KFK might be considered as a promising model compound to prevent age-associated dermal alterations.     

African Americans and renal transplantation: disproportionate need, limited access, and impaired outcomes

BACKGROUND: Renal transplantation is the therapy of choice for patients with end-stage renal disease (ESRD). However, African Americans' (AA) access to this modality is not commensurate with that of other races. This imbalance, coupled with AA disproportionately representing those with ESRD, has kept AA disadvantaged compared with other races, especially whites. METHODS: We reviewed published reports that examined the connection between race and the incidence of chronic renal failure, access to optimal therapy, and outcomes of renal transplantation. RESULTS: The incidence of ESRD in AA is 4 times greater than in whites, but AA remain less likely than whites to be referred for or undergo renal transplantation. Also, AA are at greater risk than whites to experience premature graft failure. CONCLUSIONS: ESRD management has improved dramatically with the advent of successful renal transplantation. However, AA remain significantly disadvantaged in both access and outcomes compared with whites. Further evaluation of underlying causes and development of specific remedies is warranted.