BACKGROUND:Apoptin is a protein which is synthesized in vitro or expressed by genetic engineering, without toxic and transformation activity of normal cel s. Apoptin can specifical y induce the apoptosis of tumor cel s and provide the opportunity of inhibiting the growth of cancer.
OBJECTIVE:To construct a prokaryotic expression vector for apoptin, optimize the expression conditions, and detect the activity of the purified protein.
METHODS:The apoptin gene that had been constructed was cloned into prokaryotic expression vector pET-28b (+), which was transformed into E.coli host bacteria. Apoptin was induced by isopropyl-beta-D-thiogalactoside, and analyzed by polyacrylamide gel electrophoresis. The inhibition activity of apoptin on tumor cel s was detected.
RESULTS AND CONCLUSION:Apoptin gene was successful y cloned into pET-28b (+). Apoptin protein was induced to express in form of inclusion body by isopropyl-beta-D-thiogalactoside (0.5 mmol/L) at 26 ℃. And the expression of apoptin with relative molecular mass of about 15 000 was identified by polyacrylamide gel electrophoresis. The target protein was purified by denaturation-renaturation and affinity chromatography, which has pro-apoptotic effect on lung cancer cel s H460 and H1299. The prokaryotic expression vector pET-28b-apoptin is successful y constructed. The apoptin protein with bioactivity is obtained, which al ows further functional study of apoptin.

Objective: To investigate psychological and behavioral responses and the prevalence of acute stress disorder (ASD) among the injured from a serious road traffic accident. Methods: The injured persons at ages of 7 years and older from a serious road traffic accident were enrolled, and individuals with severe injury were exclude. Participants' gender, age, educational level, marital status, injury severity, family member's injury and death during the accident and psychological and behavioral status were collected. The prevalence of ASD was estimated using a semi-structured interview and the ASD Scale, and the factors affecting the development of ASD were identified using a multivariable logistic regression model. Results: A total of 132 survivors participated in psychological crisis assessment, including 82 men (62.12%) and 50 women (37.88%) and with a mean age of (46.50±18.57) years. There were 6 participants without obvious trauma (4.54%), 113 with mild injury (85.61%) and 13 with moderate injury (9.85%), and there were 6 participants with death of their family members during this accident. Insomnia, anxiety, flashback and fear were predominant psychological and behavioral responses, with prevalence rates of 42.42%, 35.58%, 26.52% and 23.48%, respectively. The prevalence of ASD was 30.30% among participants, and a higher rate of ASD was detected among women than among men (52.00% vs. 17.07%; χ2=17.940, P<0.001). The detection of ASD was higher among participants with death of their family members than among those without death of their family members (83.33% vs. 26.98%; χ2=8.370, P=0.004), and a higher detection rate of ASD was seen among participants with moderate injury (61.54%; χ2=6.786, P=0.034). Multivariable logistic regression analysis showed a higher risk of ASD among females (OR=7.764, 95%CI: 3.187-18.915) and those with a high educational level (high school/technical secondary school, OR=6.896, 95%CI: 1.030-46.152; diploma and above, OR=71.583, 95%CI: 4.145-1 236.270). Conclusions Insomnia and anxiety are predominant psychological and behavioral responses following serious road traffic accidents, and women and individuals with a high educational level present a high risk of ASD, which requires to be given timely psychological crisis interventions.