Objective To analyze the emergency testing results of a mixed poisoning incident involving methyl acetate and dimethyl carbonate in a composite fabric processing enterprise. Methods A mixed poisoning incident involving methyl acetate and dimethyl carbonate occurred at a composite fabric processing enterprise in a city of Guangdong Province. On-site occupational health investigation data and laboratory testing results related to this incident were collected, and an integrated analysis was conducted. Results The on-site occupational health investigation revealed inadequate ventilation and non-standard use of personal protective equipment. Volatile organic component analysis of raw and auxiliary materials showed that methyl acetate and dimethyl carbonate had relatively high percentages of peak area among all used volatile organic chemical agents in post-incident emergency testing, accounting for 65.10% and 38.25%, respectively. The exposure concentration of short term (C_STE) of methyl acetate in the production line air was 15.13 mg/m³. In the chemical storage area, C_STE of methyl acetate and methanol were 451.04 and <0.21 mg/m³, respectively, all below their respective occupational exposure limits (500.00 and 50.00 mg/m³). In the poisoned workers, blood methanol, blood formic acid, and urinary formic acid levels were 147, 414, and 4 389 mg/L, respectively. Conclusion Occupational exposure to methyl acetate and dimethyl carbonate may lead to acute occupational poisoning and cause health damage. Employers should fulfill their responsibilities for occupational disease prevention by ensuring proper operation of protective facilities, while workers should enhance awareness of occupational disease prevention and correctly use personal protective equipment.

OBJECTIVETo observe the effect of rosiglitazone on the content of cholesterol and expressions of Acy-coenzyme A: cholesterol acyltransferase 1 (ACAT-1) and scavenger receptor class B type I (SR-BI) in RAW264.7 macrophage-derived foam cells and explore the anti-atherosclerotic mechanism of rosiglitazone.

METHODSRAW264.7 macrophages were incubated with oxidized low-density lipoproteins (ox-LDL) or with both ox-LDL and rosiglitazone (5, 10, or 20 µmol/L). Oil red O staining was used to observe the formation of foam cells, and cholesterol oxidase was used to determine the content of cellular cholesterol contents. Western blotting was used observe the expressions of ACAT-1 and SR-BI in RAW264.7 foam cells.

RESULTSCompared with the control cells, RAW264.7 macrophage-derived foam cells showed significantly increased contents of total cholesterol and free cholesterol (P<0.01) and ACAT-1 expressions (P<0.05) with mildly increased SR-BI expression (P>0.05). Rosiglitazone treatments significantly lowered the contents of total cholesterol and free cholesterol (P<0.05), decreased the expression of ACAT-1 (P<0.05), and increased SR-BI expression (P<0.05) in the foam cells in a dose-dependent manner.

CONCLUSIONRosiglitazone can decrease the contents of total and free cholesterol, down-regulate ACAT-1 expression and up-regulate SR-BI expression in the foam cells produce the anti-atherosclerotic effect.

Acetyl-CoA C-Acetyltransferase ; metabolism ; Cell Line ; Cholesterol ; metabolism ; Foam Cells ; cytology ; drug effects ; metabolism ; Humans ; Scavenger Receptors, Class B ; metabolism ; Thiazolidinediones ; pharmacology