Organochlorine chemicals and neurodegeneration among elderly subjects in Costa Rica.

BACKGROUND: We previously screened 400 elderly Costa Ricans for neurodegenerative disease. Those reporting occupational pesticide exposure (18%) had an increased Parkinson׳s disease (PD) risk (OR 2.57, 95% CI 0.91-7.26), and worse cognition (Mini-Mental States Exam (MMSE) 24.5 versus 25.9 points, p=0.01). We subsequently measured long-lasting organochlorine pesticides (ß-HCH, DDE, DDT, and dieldrin) in a sub-sample (n=89). Dieldrin and ß-HCH have been linked to PD, and DDE to Alzheimer׳s disease. METHODS: We ran regression models for MMSE and tremor-at-rest to assess associations with pesticides in 89 subjects. RESULTS: The percent of ß-HCH, DDE, DDT (parent compound for DDE), and dieldrin above their limit of detection (LOD) were 100%, 93%, 75%, and 57%, respectively. Tremor-at-rest was found in 21 subjects, and the mean MMSE was 25. Those who reported occupational pesticide exposure (n=36) had more detectable dieldrin samples (p=0.005), and higher mean levels of dieldrin (p=0.01), than those not reporting exposure. Other pesticides did not differ between those with and without self-reported occupational exposure. There was a positive but non-significant trend of higher risk for tremor-at-rest with higher dieldrin (p=0.10 for linear trend). Neither DDE nor DDT showed a relationship with MMSE. However, after excluding two outliers with the lowest MMSE scores, higher DDT levels showed some modest association with lower MMSE (p=0.09 for linear trend). CONCLUSIONS: Our data are limited by small sample size. However, dieldrin was high in our population, has been previously linked to PD, and could be partly responsible for the excess PD risk seen in our population.

Why youths stay away from health centres: an assessment of youth health needs and health care services utilization

OBJECTIVE: To determine the extent to which the primary health care services meet the needs of adolescents in the North-West Health Region, Trinidad. DESIGN and METHODS: A systematic sample of Government and Government assisted elementary, secondary and technical/vocational schools in the North-West was included in the study. Between January and February of 1999, self administered questionnaires were completed by 300 students in the 11 to 19 age-group randomly selected from the schools' sample. RESULTS: Only 23.6 percent of the sample went `most often' to Health Centres `at some time' - 167 (56 percent) - the major source of discomfort was the lengthy waiting period (82.7 percent) while 22 percent felt that the attitude of the deliverers of the service was either poor or very poor. Young people requested that the community health administration provide a range of services that include sport and recreation (50.7 percent), educational programmes (48.6 percent), sex education (36.1 percent), career guidance (34.8 percent), counselling (30.7 percent). They preferred these services to be delivered in a building specially designed for that purpose. CONCLUSIONS: The health services currently being provided do not meet the needs of the youth. Their preference is for a mix of services that would focus on their physical, emotional and social needs. This would require a multisectoral collaboration and the participation of youth in the planning and development of such an initiative. (Au)

Protection of C57BL/10 mice by vaccination with association of purified proteins from Leishmania (Leishmania) amazonensis.

In the past few years, induction of protective immunity to cutaneous leishmaniasis has been attempted by many researchers using a variety of antigenic preparations, such as living promastigotes or promastigote extracts, partially purified, or defined proteins. In this study, eleven proteins from Leishmania (Leishmania) amazonensis (LLa) with estimated molecular mass ranging from 97 to 13.5kDa were isolated by polyacrylamide gel electrophoresis and electro-elution. The proteins were associated as vaccine in different preparations with gp63 and BCG (Bacilli Calmette-Guérin). The antigenicity of these vaccines was measured by their ability to induce the production of IFN-gamma by lymphocyte from subjects vaccinated with Leishvacinregister mark or target. The immunogenicity was evaluated in vaccinated mice. C57BL/10 mice were vaccinated with three doses of each vaccine consisting of 30 microg of each protein at 15 days interval. One hundred microg of live BCG was only used in the first dose. Seven days after the last dose, they received a first challenge infection with 10(5) infective promastigotes and four months later, a second challenge was done. Two months after the second challenge, 42.86% of protection was obtained in the group of mice vaccinated with association of proteins of gp63+46+22kDa, gp63+13.5+25+42kDa, gp63+46+42kDa, gp63+66kDa, and gp63+97kDa; 57. 14% of protection was demonstrated with gp63+46+97+13.5kDa, gp63+46+97kDa, gp63+46+33kDa, and 71.43% protection for gp63 plus all proteins. The vaccine of gp63+46+40kDa that did not protect the mice, despite the good specific stimulation of lymphocytes (LSI = 7. 60) and 10.77UI/ml of IFN-gamma production. When crude extract of L. (L.) amazonensis was used with BCG a 57.14% of protection was found after the first challenge and 28.57% after the second, the same result was observed for gp63. The data obtained with the vaccines can suggest that the future vaccine probably have to contain, except the 40kDa, a cocktail of proteins that would protect mice against cutaneous leishmaniasis.