Objective: To explore the health status of the workers who were leaving their posts from small-scaled coal mines, and to provide evidence for coal workers’ pneumoconiosis prevention and safeguard measures. Methods: In 2017, 1008 workers from the coal mine in a town were monitored for occupational health, and the effects of working type, age were analyzed and evaluated. Results: The health monitoring of the mine workers in this town showed high rate of the abnormal detection of respiratory system and cardiovascular system, the incidence rate of pneumoconiosis was up to 34.82%. The incidence of pneumoconiosis in different types of work was not the same (P<0.05) , and the incidence of tunneling workers' pneumoconiosis was the highest. Pneumoconiosis detection rate increased with age (P<0.05) . The difference of pneumoconiosis detection rate among workers of different ages was statistically significant (P<0.05) , among which the pneumoconiosis detection rate was the highest in the group of 40 years old. Conclusion The pneumoconiosis is serious in small coal mines in this town. It should strengthen the prevention of diseases such as respiratory system and cardiovascular system of coal mine workers, and pay attention to their health management and prolong the life of patients with pneumoconiosis.

Objective To analyze the status of Leishmania infantum asymptomatic infection in human population of a Kala-azar endemic area in Wenxian County,Gansu Province,and to evaluate the tests used.Methods Blood samples were tested by PCR using two pairs of primers,RV1-RV2 and K13A-K13B,for detecting Leishmania-specific DNA.ELISA and rK39-dipstick were used to detect Leishmania-specific antibodies.Results The positive rate of PCR,ELISA and rK39-dipstick was 30.9%(83/269),24.2%(65/269) and 0(0/269) respectively.Conclusion The prevalence of asymptomatic infection of L.infantum in humans is high in the area.PCR test based on RV1-RV2 and K13A-K13B primer pairs is a sensitive and specific method for detecting the asymptomatic infection.

Background Coal workers' pneumoconiosis is a serious occupational disease in China. Exhaled volatile organic compounds (VOCs) can serve as the "breath fingerprint" of internal pathological processes, which provides a theoretical basis for exhaled VOCs to be used as potential non-invasive biomarkers for early diagnosis of coal workers' pneumoconiosis. Objective To screen out the characteristic VOCs and important characteristic VOCs of exhaled air in patients with coal workers' pneumoconiosis, and to explore the potential of these VOCs as biomarkers for early non-invasive diagnosis of the disease. Methods In this study, 27 VOCs in the exhaled breath of 22 patients with stage I coal workers' pneumoconiosis, 77 workers exposed to dust, and 92 healthy controls were quantitatively detected by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). Substances with P<0.05 in univariate analysis and variable importance projection (VIP) >1 in supervised orthogonal partial least squares discriminant analysis (OPLS-DA) model were selected as the characteristic VOCs for early diagnosis of coal workers' pneumoconiosis. Age was included in the LASSO regression model as a covariate to screen out important characteristic VOCs, and the diagnostic performance was evaluated by receiver operating characteristic (ROC) curve. Spearman correlation was further used to explore the correlation between important characteristic VOCs and clinical lung function indicators. Results Through univariate analysis and OPLS-DA modeling, 8 VOCs were selected, including 2-methylpentane, 3-methylpentane, n-hexane, methylcyclopentane, n-heptane, methylcyclohexane, 4-methyl-2-pentanone, and 2-hexanone, in exhaled breath of patients with coal workers' pneumoconiosis. The concentrations of 4 VOCs, including 3-methylpentane, n-hexane, 4-methyl-2-pentanone, and 2-hexanone, showed a decreasing trend with the increase of dust exposure years. By LASSO regression, the important characteristic VOCs of the coal workers' pneumoconiosis group and the dust exposure group were n-hexane, methylcyclohexane and 4-methyl-2-pentanone, and the important characteristic VOCs of the coal workers' pneumoconiosis group and the healthy group were 2-methyl-pentane and 4-methyl-2-pentanone. The ROC analysis showed that the area under the curve (AUC) of n-hexane, methylcyclohexane, and 4-methyl-2-pentanone were 0.969, 0.909, and 0.956, respectively, and the AUC of combined diagnosis was 0.988 and its Youden index was 0.961, suggesting that these results can serve as a valuable reference for further research on early diagnosis. The Correlation analysis found that there was a positive correlation between n-hexane and lung function indicators in the important characteristic VOCs, indicating that it could indirectly reflect the obstruction of lung function ventilation, further proving that important characteristic VOCs have the potential to monitor lung function decline. Conclusion Three important characteristic VOCs selected in this study have the potential to be used as non-invasive biomarkers for early diagnosis and disease monitoring of coal workers' pneumoconiosis, and are worthy of further study and verification.