Objective To investigate the correlation between methylation status and death-associated protein kinase 1 (DAPK1) in SiHa and Hela cell line of cervical carcinoma and intervention of DNA methyltransferase inhibitor 5-azacytidine on the expression of DAPK1 and the proliferation of the cells. Methods DAPK1 methylation status was analyzed using methylation-specific PCR methods. The expression of mRNA and protein of DAPK1 were analyzed by RT-PCR and SABC methods after the treatment with 5-azacytidine. MTT assay was used to observe the changes of proliferation activity of the cells after 5-azacytidine treatment. Results DAPK1 genes were methylated and did not express in SiHa cells in the cervical carcinoma. Its expression could be restored by 5-azacytidine. MTT assay showed 5-azacytidine could weaken the proliferation of cancerous cells. Conclusion DAPK1 methylation plays an important role in the carcinogenesis of cervical cells and can reexpress after the treatment with 5-azacytidine which also restored its inhibitory function on carcinoma.

Mock circulatory system (MCS) is an experimental platform for simulating hemodynamic performance of human circulatory system, and has been widely used in in-vitro hemodynamic performance evaluation of passive devices such as ventricular assist devices (VADs), artificial valves, as well as hemodynamic responses of mock circulation loop. MCSs are capable of simulating various physiological conditions, including health, exercise, and heart failure, by adjusting drive element of heart simulator and lumped-parameter element of vasculature components. Since 1 960 s, the research and development target of MSCs has evolved from meeting the basic performance evaluation requirement of VADs and mechanical valve to mimicking local hemodynamic characteristics in vital organs. This review summarizes the design principles, system construction of MCSs as well as its research progress and future prospects.