Search

Objective To study the effect of cordycepin on proliferation, apoptosis and inflammatory reaction of human keratinocyte cell line HaCaT induced by TNF-α. Methods HaCaT cells were divided into control group, model group and intervention groups including low, middle, high dose (cordycepin 25 μmol/L, 50 μmol/L and 100 μmol/L, respectively). HaCaT cells were incubated with by 40 μg/L TNF-α in model group and cordycepin intervention group for 24 hours. Then, the cordycepin intervention groups were incubated with corresponding cordycepin for 24 hours. Cell proliferation was detected by CCK-8 method. Apoptosis was detected by flow cytometry. And mRNA expression of interleukin (IL)-8, IL-1β was detected by RT-qPCR. Results After 24 hours of cordycepin incubation, cell proliferation rate decreased (P＜0.05), cell apoptosis rate increased(P＜0.05)and mRNA expression of IL-8 and IL-1β decreased (P＜0.05). Conclusions Cordycepin can inhibit TNF-α-induced proliferation and inflammatory reaction of HaCaT cells and promote apoptosis of these cells.

A method of spontaneous deposition of 210Po on a silver disc was used to prepare the standard plane source in a 210Pb solution. The prepared source was measured by an alpha spectrometer. There was a unique alpha peak of 5.304 MeV with a full width at half maximum of 23.92 keV in the measured spectrum. A plateau length of about 1000 V was given in the plateau curve measued with a multi-wire proportional counter. The determined surface emission rate was 2.565 ×104 min-1 at JAN. 3RD , 2019, with the extended uncertainty of 2.7% (k=2). Some MPC9604 gas-flow low background gross alpha and gross beta counters were used to test the source according to the verification regulation JJG 1100-2014. All the α detection efficiencies were not less than 77%, the repeatability within 1.5% and the α interference to β channel not greater than 2.5%. It’s showed that the prepared source was in good quality and performance to meet the calibration of gas-flow low background gross alpha and gross beta counters.