Early flattening of the oxygen pulse during the cardiopulmonary exercise test in asymptomatic adults and its association with cardiovascular risk factors.

BACKGROUND: Individuals with cardiovascular exercise limitations present oxygen pulse morphology with early flattening (plateau) during the cardiopulmonary exercise test (CPET). Although this oxygen pulse response is well known in cardiac patients, these changes' prevalence and clinical relevance in asymptomatic individuals are not known. We aimed to quantify the proportion of asymptomatic adults with an early flattening of the oxygen pulse and investigate its association with classical cardiovascular risk factors. METHODS: We carried out a cross-sectional study with a sample of 824 adults aged between 18 and 80 years. We assessed anthropometry, body composition, and cardiovascular risk. In addition, we obtained cardiorespiratory and metabolic responses during a ramp protocol treadmill CPET. RESULTS: The prevalence of early flattening of the oxygen pulse was 36.8%. These participants were predominantly females, older, less educated, with a higher body mass and percentage of fat and a lower percentage of lean body mass. After a multinominal multiple logistic regression analysis, we identified female sex (odds ratio, 5.46: 95% confidence interval, 3.73-7.99), low education (2.24: 1.47-3.42), dyslipidemia (1.67: 1.14-2.45), smoking (1.64: 1.00-2.69), and physical inactivity (1.39: 1.02-1.96) as the leading independent predictors of the early flattening of oxygen pulse. CONCLUSION: The early flattening of oxygen pulse is common in asymptomatic adults and is highly determined by modifiable cardiovascular risk factors. These results suggest that identifying the early flattening of oxygen pulse may be helpful in the prevention of cardiovascular diseases.

Evaluation of genotoxic and cytotoxic effects in buccal mucosa cells of welders in the cities of Cubatão and Santos, state of São Paulo, Brazil.

BACKGROUND: Approximately 5 million workers are estimated to be occupationally exposed to welding fumes worldwide. Nickel and chromium are genotoxic metals found in welding fumes, therefore welders are exposed to these metals at the workplace. OBJECTIVE: The objective of the present study was to investigate the frequency of cytotoxic and genetic damage in cells harvested from the oral mucosa of welders and also from a group of workers not exposed to metallic fumes. METHODS: A total of 44 individuals, divided into 2 groups - welders and non-welders - were compared using the micronucleus assay technique and cell death (pyknosis, karyorrhexis and karyolysis) on buccal mucosa cells of welding workers. The examined cells were stained with Feulgen/Fast Green. Results: Welders exhibited higher frequency (p<0.05) of cytotoxicity than the group of volunteers not exposed to metallic fumes. CONCLUSION: The results of this preliminary study suggest that the frequency of cytotoxic damage in buccal mucosa cells might be higher among welders compared to non-welders.

CONTEXTO: Estima-se que no mundo existam, aproximadamente, 5 milhões de trabalhadores expostos ocupacionalmente à fumaça de soldagem. Níquel e Cromo são metais que podem ocasionar danos ao material genético, e soldadores, por força do ofício, são rotineiramente expostos a eles. OBJETIVO: O objetivo do presente estudo foi investigar a frequência de danos citotóxicos e genotóxicos em células da mucosa bucal de um grupo de soldadores. MÉTODOS: Um total de 44 indivíduos, distribuídos em 2 grupos - soldadores e não soldadores -, foi comparado utilizando a técnica do ensaio do micronúcleo e morte celular (picnose, cariorrexe e cariólise) em células da mucosa oral de trabalhadores de soldagem. As células examinadas foram coradas com Feulgen/Fast-green. RESULTADO: Os soldadores apresentaram maior frequência (p<0,05) de alterações indicativas de citotoxicidade quando comparados ao grupo de indivíduos não expostos a fumos metálicos. CONCLUSÃO: Os resultados deste estudo preliminar sugerem que soldadores apresentam maior frequência de danos citotóxicos e morte celular em células da mucosa bucal que trabalhadores não expostos.