Objective: Application of magnetic nanoparticles as gene carrier in gene therapy has developed quickly. This study was designed to investigate the preparation of superparamagnetic dextran-coated iron oxide nanoparticl...Objective: Application of magnetic nanoparticles as gene carrier in gene therapy has developed quickly. This study was designed to investigate the preparation of superparamagnetic dextran-coated iron oxide nanoparticles (SDION) and the feasibility of SDION used as a novel gene carrier for plasmid DNA in vitro. Methods: SDION were prepared by chemical coprecipitation and separated by gel filtration on Sephacryl S-300HR, characterized by TEM, laser scattering system and Vibrating Sample Magnetometer Signal Processor. The green fluorescent protein (pGFP-C2) plasmid DNA was used as target gene. SDION-pGFP-C2 conjugate compounds were produced by means of oxidoreduction reaction. The connection ratio of SDION and pGFP-C2 DNA was analyzed and evaluated by agarose electrophoresis and the concentration of pGFP-C2 in supernatant was measured. Using liposome as control, the transfection efficiency of SDION and liposome was respectively evaluated under fluorescence microscope in vitro. Results: The diameter of SDION ranges from 3 nm to 8 nm, the effective diameter was 59.2 nm and the saturation magnetization was 0.23 emu/g. After SDION were reasonably oxidized, SDION could connect with pGFP-C2 to a high degree. The transfection efficiency of SDION as gene carrier was higher than that of liposome. Conclusion: The successes in connecting SDION with pGFP-C2 plasmid by means of oxidoreduction reaction and in transferring pGFP-C2 gene into human bladder cancer BIU-87 cells in vitro provided the experimental evidence for the feasibility of SDION used as a novel gene carrier.展开更多
小儿误食异物（foreign body ingestion,FBI）在小儿外科门诊中经常碰到,其中80％ ～ 90％可以自行通过胃肠道排出体外,不到1％伴发严重并发症,如肠穿孔、主动脉食管瘘等[1-2].鉴于此,结合目前在消化道异物处理上没有一个完善、被广泛...小儿误食异物（foreign body ingestion,FBI）在小儿外科门诊中经常碰到,其中80％ ～ 90％可以自行通过胃肠道排出体外,不到1％伴发严重并发症,如肠穿孔、主动脉食管瘘等[1-2].鉴于此,结合目前在消化道异物处理上没有一个完善、被广泛接受而执行的治疗指南[3],本次研究搜集了3个儿童医疗中心消化道异物需要外科干预的24例病例,对异物的类型及滞留部位、就诊时间、诊治过程及术后恢复情况进行总结,为临床医生尤其门急诊医生在碰到FBI的患儿时提供帮助.展开更多
基金This project was supported by a grant from the National Natural Science Foundation of China (No. 30271300).
文摘Objective: Application of magnetic nanoparticles as gene carrier in gene therapy has developed quickly. This study was designed to investigate the preparation of superparamagnetic dextran-coated iron oxide nanoparticles (SDION) and the feasibility of SDION used as a novel gene carrier for plasmid DNA in vitro. Methods: SDION were prepared by chemical coprecipitation and separated by gel filtration on Sephacryl S-300HR, characterized by TEM, laser scattering system and Vibrating Sample Magnetometer Signal Processor. The green fluorescent protein (pGFP-C2) plasmid DNA was used as target gene. SDION-pGFP-C2 conjugate compounds were produced by means of oxidoreduction reaction. The connection ratio of SDION and pGFP-C2 DNA was analyzed and evaluated by agarose electrophoresis and the concentration of pGFP-C2 in supernatant was measured. Using liposome as control, the transfection efficiency of SDION and liposome was respectively evaluated under fluorescence microscope in vitro. Results: The diameter of SDION ranges from 3 nm to 8 nm, the effective diameter was 59.2 nm and the saturation magnetization was 0.23 emu/g. After SDION were reasonably oxidized, SDION could connect with pGFP-C2 to a high degree. The transfection efficiency of SDION as gene carrier was higher than that of liposome. Conclusion: The successes in connecting SDION with pGFP-C2 plasmid by means of oxidoreduction reaction and in transferring pGFP-C2 gene into human bladder cancer BIU-87 cells in vitro provided the experimental evidence for the feasibility of SDION used as a novel gene carrier.
文摘小儿误食异物（foreign body ingestion,FBI）在小儿外科门诊中经常碰到,其中80％ ～ 90％可以自行通过胃肠道排出体外,不到1％伴发严重并发症,如肠穿孔、主动脉食管瘘等[1-2].鉴于此,结合目前在消化道异物处理上没有一个完善、被广泛接受而执行的治疗指南[3],本次研究搜集了3个儿童医疗中心消化道异物需要外科干预的24例病例,对异物的类型及滞留部位、就诊时间、诊治过程及术后恢复情况进行总结,为临床医生尤其门急诊医生在碰到FBI的患儿时提供帮助.
