1.Expression and correlation between erythropoietin mRNA and hypoxia inducible factor-1? mRNA in rats with brain ischemic tolerance
Zhongling SUN ; Renliang ZHAO ; Ruijian DONG
Journal of Clinical Neurology 2001;0(05):-
Objective To research the expression and correlation between erythropoietin(EPO)mRNA and hypoxia inducible factor-1?(HIF-1?)mRNA in rats with brain ischemic tolerance induced by ischemic preconditioning.Methods Models of cerebral ischemic preconditioning and ischemic-reperfusion(preconditioning group)were made by twice suture method,after the short ischemic preconditioning 1 d,3 d,7 d,14 d and 21 d respectively,the models were underwent ischemic-reperfusion again.The infarct volume was measured by tetrazolium chloride(TTC)staining,the expressions of HIF-1? mRNA and EPO mRNA in the different time(1~21 d)of ischemic-reperfusion were detected by reverse transcriptase polymerase chain reaction(RT-PCR)and compared with non-preconditioning group.Results The infarct volume in the 1 d,3 d and 7 d subgroups of preconditioning group were significantly smaller compared with non-preconditioning group(all P
2.Abnormal expression of glucose regulated protein 78 in glioma and its clinical significance
Xiaojun ZHANG ; Yisong ZHANG ; Zhong WANG ; Ruijian ZHANG ; Wei SUN
Chinese Journal of Postgraduates of Medicine 2021;44(7):591-595
Objective:To observe the expression of glucose regulated protein 78 (GRP78) in glioma and its clinical value in evaluating clinical prognosis.Methods:A total of 163 patients with glioma who were surgically removed and confirmed after surgery in the People′s Hospital of Inner Mongolia Autonomous Region were collected from March 2012 to October 2015. Immunohistochemical staining was used to observe the expression of GRP78 in patients with different WHO grades of glioma. Chi square test was used to compare the expression of GRP78 in glioma patients with different age, gender and WHO grade. Whether COX regression analysis GRP78 can be used as an independent prognostic indicator was investigated. Time series test and Kaplan Meier analysis were used to analyze the survival time of patients with different GRP78 expression levels.Results:The expression of GRP78 was up-regulated in glioma, and the patients with high expression of GRP78 (positive expression/strongly positive expression) were more common in stage Ⅲ/Ⅳ than in stage Ⅰ/Ⅱ. The expression of GRP78 was not statistically significant in different age and gender groups ( P>0.05), but was statistically significant in different WHO stages ( P<0.01). GRP78 was an independent prognostic factor for glioma ( P = 0.045). The median survival time of patients with glioma was 28 months (95% CI 37.594 to 47.046), of which the survival time of patients with high expression of GRP78 was 15 months (95% CI 12.922 to 40.801); the survival time of patients with low expression of GRP78 was 35 months (95% CI 39.807 to 51.352), and the difference was statistically significant ( P<0.01). The survival time of patients with high expression of GRP78 was significantly shorter than that of patients with low expression of GRP78 ( χ2 = 13.588, P<0.01). Conclusions:The expression level of GRP78 in glioma is significantly increased; high expression of GRP78 is more common in Ⅲ/Ⅳ glioma, and GRP78 can be used as an effective index to evaluate the poor prognosis of glioma.
3. A new exploration and consideration of Type A fracture of distal femur based on finite element biomechanical analysis
Duo XU ; Ruijian SUN ; Tianyu WANG ; Xinqiang ZHAO ; Zhenggang BI ; Shuo GENG
Chinese Journal of Surgery 2019;57(11):812-817
Objective:
To investigate the changes of internal fixation stress under different angles of interior fracture line and different screw placement modes in the case of A-type distal femoral fracture.
Methods:
A 24-year-old healthy male volunteer was recruited to collect the right femur data. CATIA V5R21 software produced a 10 mm fracture gap at the external side of the femur 6.5 cm proximal to the joint line and different angle fracture lines were generated on the internal of the femur at the same height. Based on the actual measured dimensions, the three-dimensional (3D) model of the locking plate and screw was reconstructed using CATIA V5R21 software, ignoring the screw surface threads and then the assembly of the internal fixation of the titanium plate, screws and femur was done. All models were meshed using Hypermesh 13.0 software. The assembled 3D model was input into ABAQUS 6.14 to generate a finite element model. Preliminary finite element biomechanical analysis was performed using the four medial fracture line angles and the stress distribution of the internal fixation under the three screw placement modes, and then the analysis was continued after the optimal screw placement method was re-determined.
Results:
Under an axial loading of 700 N, with the increase of the angle of the fracture line, the stress of the lateral internal fixation gradually increased, and the displacement of the proximal end of the fracture gradually increased. The sequential screw placement method was superior to the leaping screw placement method. The placement of the first screw at the proximal end of the fracture was critical to the distribution of the internal fixation stress.
Conclusions
The operation plan of the type A of distal femoral fracture needs to be confirmed according to the internal and external fracture′s condition. When the fracture line is at a excessive positive angle or a negative angle, a simple lateral fixation may not provide a stable fracture fixation so that other fixation methods are needed.