Objective To investigate the relationship between the expression of β-catenin and drug-resistance mechanism of choriocarcinoma according to the expression of β-catenin in JEG-3 cells (human choriocarcinoma cell line) and drug resistant JEG-3/VP16 cells.Methods The mRNA and protein expressions of β-catenin were analyzed with reverse transcription-polymerase chain reaction(RT-PCR) and Western blotting.Flow cytometry was used to determine the percentages of β-catenin-positive cells in the two choriocarcinoma cell lines.Results Both drug resistant choriocarcinoma cells and drag sensitive cells were found to express β-catenin; but the expression of β-catenin mRNA (1.43 ±0.24) and protein(1.49 ±0.17)in drug resistant choriocarcinoma cells was found much higher than that in drug sensitive cells(0.65 ±0.14,0.66 ±0.16,P ＜0.01).And according to detect by flow cytometry,we found the number of β-catenin-positive cells in JEG-3/VP16 cells [(40.13 ±5.17) ％] was much more than that in JEG-3 cells [(13.15 ± 1.48) ％,P ＜ 0.01].Conclusions β-catenin was highly expressed in the drug resistant choriocarcinoma cell line (JEG-3/VP16).It indicates β-catenin might be involved in the drug resistance mechanism of choriocareinoma.

Objective To characterize the distribution and assess the exposure to phthalic acid esters （PAEs） in the indoor dust of Shanghai City. Methods Samples were collected from 33 sampling sites， including homes， hotels， offices and public places， in Shanghai in 2018， 2019， and 2020. The samples were pretreated by 100 sieves， extracted and concentrated， and then analyzed by gas chromatography-mass spectrometry in selected ion mode （SIM）. Results Results on the characteristics of PAEs in indoor dust in different places showed that concentrations of PAEs were in a range of <0.01-2 464 mg·kg^-1.The average concentration of 16 PAEs was 613 mg·kg^-1. Bis（2-ethylhexyl） phthalate （DEHP）， di-iso-butyl phthalate （DiBP）， di-n-butyl phthalate （DBP） and di-n-octyl phthalate （DnOP） were the main components of PAEs in indoor dust， accounting for approximately 99.5% of 16 PAEs. The intake of DEHP， DBP， DEP and BBP was lower than the tolerable daily intake （TDI） and reference doses （RfD） set by EU CSTEE and U.S. EPA. Conclusion Average daily dose （ADD） via indoor dust is estimated， and the order of intake through different pathways is hand-oral intake>skin contact>respiratory inhalation. Exposure risk of PAEs in children is greater than that in adults.