Objective To investigate the effect of anti-sense osteopontin(ANOPN)on proliferation and metastasis of esophagus cancer cells.Methods An OPN gene recombinant expression vector plasmid was constructed by RT-PCR from human umbilical vein endothelial cell gene and cloned into a mammalian expression vector pcDNA3.1(+).PcDNA3.1-ANOPN was introduced by LipofectinTM.Positive cell clones(ECA-ANOPN),vector-transfected cells ECA-vect and blank cell ECA were used as three groups.RT-PCR and immunocytochemistry assay were used to investigate the expressions of OPN mRNA and protein.The metastasis characteristics of cells were studied by Transwell method.Results The vector was constructed successfully,the sequencing result was identical with that reported in GenBank.Compared with vector-transfected cells(ECA-vect cells) and ECA cells,the growth rate of ECA-ANOPN cells was significantly slowed(P

Objective To investigate the activity concentration of 90St in tea produced in Chinese typical regions,enrich the baseline data for 90Sr level in Chinese tea,and evaluate possible exposure doses to people.Methods Samples were carbonized,ashed,digested and leached,and then extraction chromatography method was used to separate 90Sr and 90y.After preparation of sample source,radioactivity of 90Y was measured using low-level α/β counter.Results Twenty six kinds of tea produced in 16 typical regions from 26 cities of 16 provinces were collected in 2016,and their 90Sr activity concentrations were analyzed using the separation method of di (2-ethylhexyl) phosphate (HDEHP) extraction chromatography.The results revealed that the activity concentrations in 26 kinds of tea samples ranged from 0.28 to 3.78 Bq/kg,and contributed possible exposure doses of 0.44 × 10-2-6.00 × 10-2 μSv to each people.Conclusions These doses were far less than the ICRP annual dose limit of 1 mSv for the public,suggesting less impact on people's health.