RESUMEN
Asphyxia during birth can cause gross brain damage, but also subtle perturbations expressed as biochemical or motor deficits with late onset in life. Thus, it has been shown that brain dopamine levels can be increased or decreased depending upon the severity of the insult, and the region where the levels are determined. In this study, perinatal asphyxia was evoked by immersing pup-containing uterus horns removed by hysterectomy in a water bath at 37 degrees C for various periods of time from 0 to 20 min. After the insult, the pups were delivered, given to surrogate mothers, treated with nicotinamide, further observed and finally, 4 weeks later, killed for monoamine biochemistry of tissue samples taken from substantia nigra, neostriatum and nucleus accumbens. The main effect of perinatal asphyxia was a decrease in dopamine and metabolite levels in nucleus accumbens, and a paradoxical increase in the substantia nigra. Nicotinamide (100 mg/kg i.p., once a day for 3 days, beginning 24 h after the perinatal asphyctic insult) prevented the effect of asphyxia in nucleus accumbens. Furthermore, striatal dopamine levels were increased by nicotinamide in asphyctic animals. No apparent changes were observed in substantia nigra. A prominent unexpected effect of perinatal asphyxia alone was on the levels of the metabolite of 5-hydroxytryptamine, 5-hydroxyindoleacetic acid (5-HIAA), which were increased in substantia nigra and decreased in both neostriatum and accumbens. However, nicotinamide increased 5-HIAA levels in all regions, which appeared to be related to the extent of the asphyctic insult. These results suggest that nicotinamide is a useful treatment against the long-term consequences produced by perinatal asphyxia on brain monoamine systems, and that there is a therapeutic window following the insult, providing a therapeutic opportunity to protect the brain.
Asunto(s)
Asfixia/tratamiento farmacológico , Asfixia/metabolismo , Ganglios Basales/metabolismo , Monoaminas Biogénicas/metabolismo , Niacinamida/farmacología , Animales , Animales Recién Nacidos , Ganglios Basales/efectos de los fármacos , Cesárea/métodos , Femenino , Niacinamida/uso terapéutico , Embarazo , RatasAsunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Mycobacterium tuberculosis/clasificación , Tuberculosis Pulmonar/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Adulto , Comorbilidad , Femenino , Honduras/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tuberculosis Pulmonar/diagnósticoRESUMEN
OBJECTIVES: A cross-sectional study was conducted to evaluate the relationship between respiratory health and paraquat exposure. METHODS: The study population was selected from among workers at 15 Nicaraguan banana plantations which relied on paraquat for the control of weeds. All the workers were interviewed after they received their job assignment for the day of the survey, and all who reported never having applied paraquat and all who reported more than 2 years of cumulative exposure as applicators of paraquat with knapsack sprayers were invited for medical evaluation. One hundred and thirty-four exposed workers and 152 unexposed workers were administered a questionnaire interview asking about exposure and respiratory symptoms, and they underwent spirometric testing of forced expiratory volume in 1 s (FEV1.0) and forced vital capacity (FVC). RESULTS: In the exposed group 53% reported having experienced a skin rash or burn resulting from paraquat exposure, 25% reported epistaxis, 58% nail damage, and 42% paraquat splashed in the eyes. There was a consistent dose-response relationship between intensity of exposure (as indicated by a history of skin rash or burn) and the prevalence of dyspnea. This relationship was more marked for more severe dyspnea. There was a 3-fold increase in episodic wheezing accompanied by shortness of breath among the more intensely exposed workers. There was no relationship between exposure and FEV1.0 or FVC. CONCLUSIONS: The high prevalence of respiratory symptoms associated with exposure, in the absence of spirometric abnormalities associated with exposure, could be a result of unmeasured gas exchange abnormalities among workers with long-term exposure to paraquat.
Asunto(s)
Enfermedades de los Trabajadores Agrícolas/inducido químicamente , Disnea/inducido químicamente , Herbicidas/efectos adversos , Paraquat/efectos adversos , Adulto , Enfermedades de los Trabajadores Agrícolas/epidemiología , Enfermedad Crónica , Estudios Transversales , Disnea/epidemiología , Exantema/inducido químicamente , Exantema/epidemiología , Femenino , Humanos , Masculino , Análisis Multivariante , Enfermedades de la Uña/inducido químicamente , Enfermedades de la Uña/epidemiología , Nicaragua , Prevalencia , Fumar/efectos adversos , Espirometría , Encuestas y Cuestionarios , ZingiberalesRESUMEN
Two questionnaires about respiratory symptoms were evaluated for reliability and ability to diagnose chronic bronchitis in a study population of 129 Nicaraguans (110 workers and 19 patients with chronic bronchitis). The first questionnaire (AQ) had symptom questions that were based on British Medical Research Council (MRC) questions, adapted to local Spanish. The second questionnaire (MRCQ) contained MRC symptom questions translated directly into Spanish. The reliability of the questions was measured in a test-retest procedure. The questionnaire-based diagnosis of chronic bronchitis was compared with the diagnosis made by a physician (for workers) or from the hospital records (for patients). The questions concerning symptoms in both questionnaires were of acceptable reliability. For the diagnosis of chronic bronchitis in workers, the AQ showed similar sensitivity, a somewhat higher specificity, and a substantially higher positive predictive value (90%) than the MRCQ (57%). Among the patients, the AQ identified 17 patients as positive (sensitivity 89%), while the MRCQ identified 15 (sensitivity 79%). respiratory questionnaire; reliability; chronic bronchitis; Nicaragua Hanley & Belfus, Inc. Int J Occup Environ Health 1077-3525 2 2 1996 April/June Chronic Exposure to Cigarette Smoke Inhibits the Stimulating Effects of Mineral Fibers on the Production of Tumor Necrosis Factor by Alveolar Macrophages of Rats 95 98 EN Yasuo Morimoto Department of Environmental Health Engineering, University of Occupational and Environmental Health, Japan 1-1, Iseigaoka, Yahatanishiku, Kitakyushu 807, Japan. Ziro Nambu Hajime Hori Tohru Tsuda Hiroshi Yamato Toshiaki Higashi Yasuyuki Yokosaki Masamitsu Kido Isamu Tanaka The objective of this study was to evaluate the chronic combined effects of mineral fibers and cigarette smoke on the production of tumor necrosis factor (TNF) by alveolar macrophages. The authors chronically exposed ten rats to cigarette smoke in vivo and measured the production of TNF by alveolar macrophages in the presence of mineral fibers in vitro. For smoke exposure, rats were divided into two groups. Five rats were exposed daily to a concentration of 10 mg/m(3) of cigarette smoke for six hours a day, five days a week, for four weeks, and five rats (control) were not exposed to smoke. A broncho-alveolar lavage was performed after the smoke exposure, and the recovered alveolar macrophages were incubated with either chrysotile or ceramic fibers on a microplate for 24 hours. TNF activity in the supernatant was determined by the L929 bioassay. When alveolar macrophages were not stimulated by mineral fibers, TNF production tended to be lower in smoke-exposed alveolar macrophages than in unexposed ones, although the difference was not significant statistically. When alveolar macrophages were stimulated in vitro by chrysotile or ceramic fibers, both fibers stimulated TNF production, but TNF production in smoke-exposed alveolar macrophages was lower than that in unexposed macrophages. These results revealed that long-term exposure to cigarette smoke inhibited the stimulating effect of mineral fibers on the production of TNF.
RESUMEN
The main objective was to derive reference equations for the FVC, FEV1, and FEV1/FVC ratio for healthy Nicaraguan male workers without current occupational exposure to agents hazardous to the lungs. Age, height, and weight were included as independent variables in the analysis, but only age and height showed significant effects on the indices studied. A nonlinear relationship with age was observed for FVC and FEV1, with a shift in the slope at the age of 32 years. Linear, quadratic, and multiphase models were tested in order to assess the best reference equation. The multi-phase model most closely fitted the values measured. The FEV1/FVC ratio showed a significant linear negative correlation with age. A comparison between the equations derived from this material and those reported in other studies revealed substantial differences. Racial, genetic, nutritional, work and sociocultural factors could account for the differences.
Asunto(s)
Ocupaciones , Ventilación Pulmonar/fisiología , Adolescente , Adulto , Factores de Edad , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Nicaragua , Valores de Referencia , Espirometría , Capacidad Vital/fisiologíaRESUMEN
In 1985 the Division of Mental Health, World Health Organization, Geneva, convened a group of investigators from centers in four countries--Australia, Chile, Norway, Swaziland--to participate in a pilot study on the efficacy of school-based alcohol education. The goal of the educational program was to delay onset and minimize involvement of alcohol use among 13- to 14-year-old adolescents. Twenty-five schools in the four countries, representing middle- and lower-class populations, were randomly assigned to peer-led education, teacher-led education, or a control condition. The educational program was derived from social-psychological theory and etiological research on adolescent alcohol use. The program focused on the social and environmental influences to drink alcohol and skills to resist those influences. It consisted of five lessons over 2 months. Baseline and posttest data measured alcohol use knowledge, attitudes, skills, and friends' drinking patterns. Data were collected immediately prior to and 2 months following the educational program. The data converge on the finding that peer-led education appears to be efficacious in reducing alcohol use across a variety of settings and cultures.