EVERY Sunday,when the first ray breaks over Dawan Village in Wuwei City,Gansu Province,14-year-old Cai Hui leaps out of bed and hops on her bike.She pedals furiously to her friends'homes in neighboring villages,an...EVERY Sunday,when the first ray breaks over Dawan Village in Wuwei City,Gansu Province,14-year-old Cai Hui leaps out of bed and hops on her bike.She pedals furiously to her friends'homes in neighboring villages,and wakes them up one by one.Then all six of the sleepy-headed kids make the 15-kilometer journey to the Tengger Desert,buckets and spades in hand.After a 40-minute tractor ride along the bumpy road,they reach the 800-sq-km desert,and begin their work-afforestation.展开更多
目的利用CRISPR/Cas9基因编辑技术构建稳定敲除高迁移率族蛋白A2(high mobility group protein AT-Hook-2,HMGA2)基因的人甲状腺乳头状癌细胞系TPC-1细胞模型。方法重组pLV[2gRNA]-EGFP:T2A:Puro-U6>{hHMGA2[gRNA#A1]*}-U6>{hHMGA...目的利用CRISPR/Cas9基因编辑技术构建稳定敲除高迁移率族蛋白A2(high mobility group protein AT-Hook-2,HMGA2)基因的人甲状腺乳头状癌细胞系TPC-1细胞模型。方法重组pLV[2gRNA]-EGFP:T2A:Puro-U6>{hHMGA2[gRNA#A1]*}-U6>{hHMGA2[gRNA#A2]*}慢病毒质粒载体的构建:设计靶向HMGA2基因的Dual-gRNA序列,将合成的Dual-gRNA片段克隆到pLV[2gRNA]-EGFP:T2A:Puro-U6载体中,提取单克隆进行测序验证。成功构建的重组质粒载体进行慢病毒包装,并感染TPC-1细胞,利用嘌呤霉素进行筛选获得HMGA2敲除的单克隆,进行PCR及测序验证,实时荧光定量qPCR检测细胞中HMGA2 mRNA的敲除效率。结果经测序验证,成功构建了靶向HMGA2基因的pLV[2gRNA]-EGFP:T2A:Puro-U6>{hHMGA2[gRNA#A1]*}-U6>{hHMGA2[gRNA#A2]*}质粒。挑取单克隆进行PCR鉴定及基因测序,成功获得了HMGA2完全敲除的TPC-1细胞。经实时荧光定量qPCR检测HMGA2敲除的TPC-1细胞,未表达HMGA2 mRNA。结论利用CRISPR/Cas9基因编辑技术能成功构建稳定敲除HMGA2基因的人甲状腺乳头状癌细胞系TPC-1细胞模型。展开更多
The controlled synthesis of hollow magnetite （Fe3O4） nanospheres of varying sizes and structures was successfully obtained via a facile solvothermal process and varying cooling processes. The Fe3O4 nanospheres were ...The controlled synthesis of hollow magnetite （Fe3O4） nanospheres of varying sizes and structures was successfully obtained via a facile solvothermal process and varying cooling processes. The Fe3O4 nanospheres were characterized by X-ray diffraction, transmission electron microscopy, scanning elec- tron microscopy, and superconducting quantum interference device magnetometry. The diameters of the as-synthesized nanospheres were controlled at around 500-700 nm by simply changing the cool- ing rate, which had an obvious influence on the morphology and magnetic properties of these Fe3O4 nanospheres. While a low cooling rate triggered the formation and extension of the cracks present in the Fe3O4 nanospheres, a sudden drop of temperature tended to favor multi-site nucleation of the crystals as well as the formation of compact and smooth hollow nanospheres with superior crystallinity and high saturation magnetization. The growth mechanism of hollow magnetite oxide nanospheres was proposed and the correlation between the structure and the magnetic properties of the hollow nanospheres was discussed, which promises the potential of the hollow nanospheres in various applications such as drug delivery and cell separation.展开更多
文摘EVERY Sunday,when the first ray breaks over Dawan Village in Wuwei City,Gansu Province,14-year-old Cai Hui leaps out of bed and hops on her bike.She pedals furiously to her friends'homes in neighboring villages,and wakes them up one by one.Then all six of the sleepy-headed kids make the 15-kilometer journey to the Tengger Desert,buckets and spades in hand.After a 40-minute tractor ride along the bumpy road,they reach the 800-sq-km desert,and begin their work-afforestation.
文摘目的利用CRISPR/Cas9基因编辑技术构建稳定敲除高迁移率族蛋白A2(high mobility group protein AT-Hook-2,HMGA2)基因的人甲状腺乳头状癌细胞系TPC-1细胞模型。方法重组pLV[2gRNA]-EGFP:T2A:Puro-U6>{hHMGA2[gRNA#A1]*}-U6>{hHMGA2[gRNA#A2]*}慢病毒质粒载体的构建:设计靶向HMGA2基因的Dual-gRNA序列,将合成的Dual-gRNA片段克隆到pLV[2gRNA]-EGFP:T2A:Puro-U6载体中,提取单克隆进行测序验证。成功构建的重组质粒载体进行慢病毒包装,并感染TPC-1细胞,利用嘌呤霉素进行筛选获得HMGA2敲除的单克隆,进行PCR及测序验证,实时荧光定量qPCR检测细胞中HMGA2 mRNA的敲除效率。结果经测序验证,成功构建了靶向HMGA2基因的pLV[2gRNA]-EGFP:T2A:Puro-U6>{hHMGA2[gRNA#A1]*}-U6>{hHMGA2[gRNA#A2]*}质粒。挑取单克隆进行PCR鉴定及基因测序,成功获得了HMGA2完全敲除的TPC-1细胞。经实时荧光定量qPCR检测HMGA2敲除的TPC-1细胞,未表达HMGA2 mRNA。结论利用CRISPR/Cas9基因编辑技术能成功构建稳定敲除HMGA2基因的人甲状腺乳头状癌细胞系TPC-1细胞模型。
文摘The controlled synthesis of hollow magnetite （Fe3O4） nanospheres of varying sizes and structures was successfully obtained via a facile solvothermal process and varying cooling processes. The Fe3O4 nanospheres were characterized by X-ray diffraction, transmission electron microscopy, scanning elec- tron microscopy, and superconducting quantum interference device magnetometry. The diameters of the as-synthesized nanospheres were controlled at around 500-700 nm by simply changing the cool- ing rate, which had an obvious influence on the morphology and magnetic properties of these Fe3O4 nanospheres. While a low cooling rate triggered the formation and extension of the cracks present in the Fe3O4 nanospheres, a sudden drop of temperature tended to favor multi-site nucleation of the crystals as well as the formation of compact and smooth hollow nanospheres with superior crystallinity and high saturation magnetization. The growth mechanism of hollow magnetite oxide nanospheres was proposed and the correlation between the structure and the magnetic properties of the hollow nanospheres was discussed, which promises the potential of the hollow nanospheres in various applications such as drug delivery and cell separation.
