Objective:To evaluate the feasibility of using polyethyleneimine(PEI) coated magnetic iron oxide nanoparticles(polyMAG-1000) as gene vectors. Methods:The surface characteristies of the nanoparticles were observed with scan electronical microscope.The ability of the nanoparticles to combine and protect DNA were investigated at different PH after the polyMAG-1000 and DNA were combined at different ratio.The nanoparticles were tested as a gene vectors through transfection models in vitro. Results: Under scan electronical microscope, the diameter of the nanoparticles was about 100 nm. The nanoparticles could bind and condense DNA under acidic ,neutral and alkaline pH conditions. The nanoparticles could transfer gene into cell and express green fluorescent protein(GFP).The efficiency of transfection was the highest when the ratio of the nanoparticles and DNA was 1 ∶ 1(v ∶ w).The difference was marked in the transfection efficiency when magnetic field was added or not. Conclusion: The magnetic iron oxide nanoparticles coated with PEI may be potentially used as gene vectors.

Background:Gankyrin is an ankyrin repeat oncoprotein overexpressed and involved in the tumorigenesis and progression of various cancers. Aims:To investigate the effect and underlying mechanism of down-regulation of gankyrin expression on proliferation of gastric cancer cells. Methods:Lentivirus vector carrying gankyrin-targeted siRNA was transfected into human gastric cancer cell line MKN28. Cell proliferation,cell cycle distribution and β-catenin/ cyclin D1 signaling pathway was analyzed by MTT assay,flow cytometry and Western blotting,respectively,in gankyrin-silenced MKN28 cells and control cells. Results:The transfection efficiency of lentivirus vector was more than 90% ,and the protein expression of gankyrin in gankyrin siRNA transfected MKN28 cells was significantly repressed( P ﹤ 0. 01). Compared with cells transfected with control lentivirus and cells without transfection,MKN28 cells transfected with gankyrin siRNA showed markedly repressed cell growth after 3-day-culture;the proportion of cells in cell cycle G1 phase was significantly increased,and that in S phase was significantly decreased;down-regulated expression of β-catenin and cyclin D1 was observed(P all ﹤ 0. 01). Conclusions:Down-regulation of gankyrin expression in gastric cancer cells may induce cell cycle G1 phase arrest and inhibit cell proliferation by suppressing β-catenin/ cyclin D1 signaling pathway. Gankyrin might be a promising novel target for targeted therapy of gastric cancer.

Objective To investigate the risk factors of surgical site infection (SSI) related complications after radical gastrectomy for gastric cancer in elderly patients.Methods The clinical data of 410 elderly patients with gastric cancer who underwent radical gastrectomy was retrospectively collected from 2009 to 2016.Univariate and multivariate analysis were performed to investigate the risk factors of SSI related complications,and the impact of SSI on short-term prognosis.Results SSI developed in 50 out of 410 elderly patients who underwent radical gastrectomy for gastric cancer,including 19 incisional infections and 31 organ lacuna infections.The corresponding incidence was 12.2％,4.6％ and 7.6％,respectively.By univariate analysis,age ＞ 75 (x2 =5.315,P =0.021),preoperative anemia (x2 =3.983,P =0.046),NRS 2002 ≥ 3 (x2 =4.785,P =0.029),diabetes (x2 =5.895,P =0.015),preoperative obstruction (x2 =5.250,P =0.022),undifferentiated carcinoma (x2 =4.448,P =0.035),cardiac carcinoma (x2 =5.265,P =0.022) and combined organs resection (x2 =4.165,P =0.041) were associated with SSI.Multivariate analysis showed that advanced age (OR =2.422,P =0.016),diabetes (OR =2.524,P =0.026),preoperative obstruction (OR =2.098,P =0.047) and high NRS 2002 score (OR =1.969,P =0.043) were independent risk factors for SSI.Conclusion The independent risk factors of SSI for elderly gastric cancer patients are advanced age,diabetes,preoperative obstruction and high NRS 2002 score.