Navegando por Palavras-chave "Air pollutants"

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    Caracterização dos efeitos da exposição aos componentes do cigarro sobre o controle neural do sistema cardiovascular em ratos normotensos e ratos espontaneamente hipertensos
    (Universidade Federal de São Paulo (UNIFESP), 2011-06-29) Valenti, Vitor Engrácia [UNIFESP]; Ferreira, Celso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Objectives: To evaluate the effects of sidestream cigarette smoke (SSCS) on neural control of cardiovascular system in normotensive and spontaneously hypertensive rats (SHR). Method: Wistar, Wistar-Kyoto rats (WKY) and SHR were exposed to SSCS for three weeks, five days per week, 180 minutes per day at a concentration of carbon monoxide between 100 and 300 ppm. Baroreflex was stimulated with a vasodepressor dose of sodium nitroprusside (NPNa, 50ìg/kg, iv) and with a pressor dose of phenylephrine (PE, 8ìg/kg, iv). In order to evaluate the effects of catalase inhibition into the fourth cerebral ventricle (4th V) on cardiovascular responses, we injected the catalase inhibitor 3-amino-1,2,4-triazole (ATZ, ìg/100ìL 0.01). Results: It was observed in Wistar rats exposed to SSCS that catalase inhibition caused more intense responses on basal HR and bradycardic peak. Central catalase inhibition affected in a higher intensity baseline HR and bradycardic peak WKY rats exposed to SSCS. On the other hand, in SHR SSCS exposure affected the tachycardic peak after central inhibition of catalase in a higher intensuty. Conclusion: Exposure to SSCS alters the sympathetic component of the baroreflex in WKY and SHR and caused more severe cardiovascular responses to catalase inhibition into the 4th V in Wistar and WKY rats.
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    Delineamento e validação de matriz de exposição ocupacional à sílica
    (Faculdade de Saúde Pública da Universidade de São Paulo, 2005-01-01) Ribeiro, Fátima Sueli Neto; Camargo, Esther Archer de [UNIFESP]; Wünsch Filho, Victor; Institutuo Nacional do Câncer Coordenação de Prevenção e Vigilância Área de Vigilância do Câncer Ocupacional; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    OBJECTIVE: To develop a population-based matrix of job-exposure to crystalline silica in Brazil and to estimate its validity. METHODS: An epidemiologist and an industrial hygienist developed a matrix of job-exposure in four stages: coding of occupation variable; coding of industry variable; consensual exposure classification between researchers; and estimate of registered workforce in 1995 for each level of exposure. The cross-tabulation of the variables industry (25 columns) and occupation (347 lines) resulted in 8,675 cells, classified according to silica exposure in four levels: non-exposed, possibly exposed, probably exposed, and definitively exposed. For validating the job-exposure matrix, five industries (mining and quarrying, construction, foundry, management of technical personal and textiles), were re-coded according to exposure by external experts. Reliability of the study and external experts was evaluated by agreement measured using kappa analysis. RESULTS: The job-exposure matrix showed high coding agreement, ranging from 64.0% for foundry to 94.0% for mining. Kappa analysis showed good agreement in mining (0.9), and low or average for other sectors (ranging from 0.1 to 0.5). High specificity was found in foundry (86.5%) and mining (100.0%). Construction had 56% specificity. CONCLUSIONS: The study job-exposure matrix showed good accuracy and seems to be appropriate for estimating silica exposure among Brazilian workers.