ABSTRACT
Objective To construct and identify over?expressing lentiviral vector of mSema3A. Methods Sema3A gene of mice was amplified by PCR,then the gene was inserted into plasmids pDown?mSema3A?IRES/EGFPby Gateway technology. The plasmids pLV/EXPNZ?puro?mSema3A?IRES/EGFP were produced by recombination. After sequencing identification,the vector pLV(Exp)?Puro?CMV?mSema3A?IRES/EGFP was packed and condensed. Finally the recombinant vectors were used to transfect 293T cells to obtain virus pools. Results The recombinant lentiviral vectors were 11 538 bp with EGFP marker,and Sema3Agenes were inserted into the lentiviral vector correctly,indicating the over?expressing vector of Sema3A gene in mice was successfully constructed. Conclusion The over?expressing lentiviral vector of mSema3A was constructed correctly, which lay a foundation of screening of over?expressing strains of such gene in specific cells.
ABSTRACT
Objective To evaluate the potential mutagenicity of a new machinable bioactive glass-ceramic material.Methods Thirty N1H mouse inbred line (female:male =1:1) were divided to three groups at random (n =10),including glass-ceramic groups (oral administration of 5 g/kg glass-ceramic powder and arabic gum),negative control group (arabic gum in equal volume),and positive control group (oral administration of 40 mg/kg cyclophosphamide).The mice orally intook the equivalent liquor and were sacrificed with bone marrow cells abstracted 24 hours later.The micronucleated cells were counted in 1 000 polychromatic erythrocytes (PCE) per mouse,then the rate of the micronucleus in every group was measured.Results The rate of the micronucleus in glass-ceramic group,negative control group and positive control group was 1.31±0.53‰, 1.32±0.62‰ and 29.20±0.74‰ respectively.There was no significant difference in the rate of the micronucleus between the experimental and negative groups (P＞0.05),while a significant difference in the rate of the micronucleus was observed between experimental and positive groups (P＜0.01).Conclusion The new machinable bioactive glass-ceramic materials couldn't increase the micronucleus rate of mouse bone marrow cells.