[Studying the damages of mouse retina induced by 2,5-hexanedione].

Objective: To study toxic effects of 2,5-hexanedione (2,5-HD) on pathology and lipid peroxidation in mouse retina.

Methods: Forty-eight mice were randomly divided into blank control group (12 mice), negative control group exposed to normal solution (12 mice) and group exposed to 2,5-HD for 2. 4 and 8 weeks, respectively (24 mice) by intraperitoneal injection (2.

[NP9 gene inhibits tumorigenicity of nasopharyngeal carcinoma].

Objective: To study the effect of NP9 on the growth of transplanted nasopharyngeal carcinoma (NPC) in nude mice and explore the mechanisms involved.

Methods: Recombinant pRc/CMV2-NP9 plasmid was constructed and transfected into the NPC cell lines by lipofectamine 2000. Cell clones stably expressing NP9 were obtained by detecting the mRNA expression of NP9 in G418-resistant clones with RT-PCR.

[A study on lymphocyte DNA damage in traffic policemen in Guangzhou].

Objective: To study the effect of occupational exposure to traffic exhaust and smoking on DNA damage in traffic policemen.

Methods: 812 traffic policemen (741 men and 71 women, 130 of office-work and 682 of outside work) from 8 districts in Guangzhou were investigated. Blood samples were taken by venipuncture and lymphocytes were collected by using lymphocyte separation medium and centrifugation.