ABSTRACT
Xuzhou Medical University, relying on the National Demonstration Center for Experimental Basic Medical Science Education and the scientific research platform of Jiangsu Key Laboratory of Brain Disease Bio-information, organizes clinical medical undergraduates to participate in the innovative training program of scientific research practice. Taking the research on signal transduction of ischemic nerve cell injury as an example, this paper studies the innovative practice training on experimental ability and scientific research thinking of medical undergraduates, and preliminarily discusses the promoting effect of innovative practice training on teaching reform of biochemistry and molecular biology. Innovative training in scientific research practice provides a new teaching method, which effectively promotes the cultivation of scientific research quality of medical undergraduates and the teaching reform of theoretical courses.
ABSTRACT
Objective To investigate the effects of aggrecanase-2 knockdown in chondrocytes from rheumatoid arthritis patient by shRNA infection.Methods Cartilage harvested from rheumatoid arthritis patients who underwent total knee arthroplasty was digested by pancreatin and type Ⅱ collagen enzyme to obtain chondrocytes.Then chondrocytes were cultured and passaged to second or third generation.After aggrecanase-2 shRNA5,aggrecanase-2 shRNA6,aggrecanase-2 shRNA7,aggrecanase-2 shRNA8 infection,growth and morphological changes of the chondrocytes were examined.To select the best target sequence,mRNA expression of aggrecanase-2 and aggrecan was detected by RT-qPCR assay on day 2,5,10,represented with Ct (Cycle threshold) value.Expression of aggrecan protein was detected by immunocytochemistry,represented with IOD (integral optical density) value.Results aggrecanase-2 knockdown had no obvious effects on the morphology and growth of the chondrocytes.MOI (multiplicity of infection) was 100,50,25,and infection efficiency was 90％,60％,30％ with the corresponding viral load of 200 μl,100 μl,50 μl after transfection.mRNA expression of aggrecanase-2 was suppressed significantly,especially the group of shRNA5 which suppressed aggrecanase-2 expression from 0.876 3±0.115 6 to 0.069 9±0.015 1 (P ＜ 0.05).mRNA and protein expression of aggrecan were significantly upregulated after infection.mRNA expression of aggrecan increased from 0.992 1±0.201 3 to 3.049 2±0.278 2 (P ＜ 0.05) and protein expression of aggrecan increased from 496.160 5± 225.673 7 to 4 525.433 0±1 131.813 0 (P ＜ 0.05).Conclusion aggrecanase-2 suppression in chondrocytes by lentivirius infection is an effective method to protect the expression of aggrecan.