Objective To explore the determination of dioxin in wastewater samples pretreated by solid phase microextraction(SPME). Methods The wasterwater samples were purified and enriched by SPME, then were determined with HRGC-HRMS for the concentration of dioxin in wastewater samples. Results The most suitable conditions of the pretreatment were 30 min microextraction at 45 ℃. The detection limit was 0.05 pg/?l. RSD was lower than 10%. The recovery rates were 99%-102%. The concentration of total dioxins in wastewater sample was 0.78 pg/?l. Conclusion The method of the determination of dioxins in wastewater by SPME was simple and quick, and presented a broad prospects for application.

ObjectiveTo investigate the effect of Mashao Pingchuan decoction （MSPC） on lipopolysaccharides （LPS）-induced autophagy in human bronchial airway epithelial cells （16HBE） via the phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/mammalian target of rapamycin （mTOR） signaling pathway. Method16HBE cells were selected for the study， and cell counting kit-8 （CCK-8） was used to detect the activity of of LPS-induced 16HBE cells and the effect of MSPC-containing serum on the cells. Suitable LPS-induced 16HBE cells were screened by the CCK-8 method， and the content of tumor necrosis factor-α （TNF-α） was measured to identify the established model. And MSPC-containing serum was prepared. The cells were divided into normal group， LPS group， LPS+MSPC group， LY294002+LPS group and LY294002+LPS+MSPC group. Transmission electron microscopy was performed to observe the changes in autophagic vesicles and ultrastructure of the cells. Western blot was performed to detect the protein expressions of PI3K， phosphorylated PI3K （p-PI3K）， Akt， phosphorylated Akt （p-Akt）， mTOR， phosphorylated mTOR （p-mTOR） and microtubule-associated protein 1 light chain 3B （LC3B）， and enzyme-linked immunosorbent assay （ELISA） was used to detect the expressions of inflammatory factors interleukin-5 （IL-5）， IL-6， TNF-α and IL-10 in the five groups. ResultLPS inhibited the 16HBE cells in a dose-dependent manner. Compared with the normal group， the LPS group （150 mg·L^-1 of LPS） increased the expression of pro-inflammatory factor TNF-α after 24 h of treatment （P<0.05） and facilitated the autophagosome formation， and MSPC-containing serum exerted a concentration-dependent promotion effect on the 16HBE cells， inhibited the autophagy to a certain degree and enhanced the cell status. Western blot revealed that the protein expressions of p-PI3K， p-Akt and p-mTOR in the model group were lower （P<0.05） and the protein expression of LC3B was higher （P<0.01） than those in the normal group. Compared with the conditions in the LPS group， the protein expressions of p-PI3K， p-Akt and p-mTOR in the LPS+MSPC group were elevated （P<0.05） and that of LC3B was reduced （P<0.05）. Compared with the LPS+LY294002 group， the LY294002+LPS+MSCP group had up-regulated protein expressions of p-PI3K， p-Akt and p-mTOR （P<0.05） and down-regulated protein expression of LC3B （P<0.05）. ELISA showed that the LPS group had higher levels of IL-5， IL-6， TNF-α and IL-10 than the normal group， while the levels of TNF-α， IL-6 and IL-8 were decreased （P<0.01） and the level of IL-10 was increased （P<0.01） after treatment with MSCP. ConclusionMSCP may lower the LPS-induced autophagy in 16HBE cells and improve the inflammatory response through activating the PI3K/Akt/mTOR signaling pathway.