OBJECTIVETo assess the DNA damage of copper 8-quinolinolate (CuQ) and to elucidate the plausible mechanisms.METHODSHepG2 cells were treated with CuQ0-4 μmol·L-1 for different time,DNA damage was measured by Comet assay.Catalase (CAT) activity,glutathione(GSH) level and thiobarbituric acid reactive substances (TBARS) were measured.NF-κB was examined using Western blotting.8-Hydroxydeoxyguanosine (8-OHdG) was measured by immunoperoxidase staining analysis.RESULTSCuQ 0.5 -4 μmol·L-1 caused significant increase of DNA migration in HepG2 cells.CuQ significantly decreased levels of GSH and activity of CAT in HepG2 cells (P ＜0.05).Moreover,CuQ significantly increased accumulation of the p65 subunit of NF-κB into nucleus,levels of lipid peroxidation product TBARS and the formation of 8-OHdG (P ＜0.05).The intracellular GSH level was modulated by pre-treatment with buthionine-(S,R)-sulfoximine (BSO),depletion of GSH in HepG2 cells pre-treated with BSO dramatically increased susceptibility of HepG2 cells to CuQ-induced DNA damage.CONCLUSIONCuQ exerts DNA damage by oxidative stress and increases accumulation of p65 subunit of NF-κB into nucleus in HepG2 cells.

Objective To study the significance of DNA of Toxoplasma gondii in peripheral blood. Methods DNA of T.gondii in peripheral blood of 50 infected rats was detected by polymerase chain reaction. A pair of primers was designed, according to the sequence P30 gene specific to T.gondii, to amplify DNA from T.gondii by PCR. Results The primers amplified DNA specifically from T.gondii and could not amplify DNA from humans, uninfected rat and mouse and from Trichomonas vaginalis and Entamoeba histolytica. DNA of two Toxoplasma parasites was detected by 35 cycles of amplification, indicating a fair sensitivity of the PCR system. Conclusion PCR may have a value for early diagnosis of T.gondii infection in rat.

To adapt to the new challenge of nutrition and food safety as well as to cultivate talents with capacity of innovation and practical application, Dalian Medical University starts to explore a wide range of experimental teaching system:expanding classical confirmatory experiment, offering comprehensive and designing experiment , encouraging students to participate in scientific research , building Internet teaching platform, and initiating community practice service projects. Multiple dimensional and teaching patterns contribute to strengthen basic skills, interest in scientific research, innovation consciousness and practical ability of undergraduate students, which greatly improves their consciousness of social service and responsibility and helps to cultivate the practical professional talents.