ERK5在小鼠骨质疏松性骨折愈合过程中作用的实验研究

目的通过构建小鼠骨质疏松骨折模型,研究ERK5在骨质疏松性骨折愈合过程中的作用。方法将108只6周龄雌性昆明小鼠随机分成4组,通过手术切除小鼠双侧卵巢及小鼠股骨离断分别构建骨质疏松(OVX)和骨折模型(Fracture),然后给实验组小鼠每日腹腔注射ERK5特异性阻断剂XMD8-92,于1 w、2 w、4 w后分别处死一定数量的小鼠,取术侧股骨标本,行X线片检查、股骨骨痂Micro-CT、HE染色及免疫组织化学染色检查,观察骨折端骨小梁生长情况,骨痂内成骨相关蛋白及ERK5表达情况。结果给予实验小鼠注射XMD8-92后第2周及第4周,Fracture组小鼠骨痂生长较快,骨小梁数目较多,厚度较大,成骨相关蛋白ALP、Runx2的表达相对较多(P0.05),而Fracture+XMD8-92组小鼠骨痂生长则相对缓慢,骨小梁稀少且绯薄,结构相对较乱,碱性磷酸酶(alkaline phosphatase,ALP)、Runx2表达较少(P0.05);且OVX+Fracture+XMD8-92组小鼠与OVX+Fracture组小鼠相比,骨小梁生成更少且紊乱,骨痂生长明显延迟,ALP、Runx2表达量显著减少(P0.05)。结论 ERK5影响骨折端骨痂形成的速度和质量,在促进骨质疏松性骨折愈合过程中起着十分重要的生理作用。     

study of anatomical location of the low tibial tunnel in posterior cruciate ligament reconstruction based on CT images北大核心CSCD

Objective To measure the anatomical parameters of the simulated low tibial tunnel of posterior cruciate ligament (PCL) based on knee CT images so as to provide clinical reference for accurate location of the tunnel. Methods The CT images of 201 healthy knee joints collected at Department of Orthopedics, The Second Hospital of Lanzhou University from June 2016 to September 2021 were used for simulation of the PCL low tibial tunnel. The anatomical parameters of the tibial tunnel were measured using the RadiAnt DICOM Viewer. The primary measures included the angle between tibial plateau and tibial tunnel (ATPT) and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau (L1 and L2). The secondary measures included the angle between tibial plateau and posterior slope (PSA), the angle between tibial anatomical axis and central line of tibial tunnel (ATAA), the angle between posterior tibial slope line and the central line of tibial tunnel (APST), the anterior and posterior diameter of tibial plateau (APD), the length of posterior tibial slope (LPTS), and the length of tibial tunnel (LTT). The measurement results were analyzed according to the body height (divided into 3 groups: a 1.00 to 1.60 m group, a 1.61 to 1.70 m group, and a ≥1.71 m group) and gender using the software IBM SPSS 26. Results The primary measures: ATPT was 37.0°±4.5°, and L1 and L2 were respectively (57.8±7.4) mm and (34.5±3.3) mm. The secondary measures: PSA 128.1°±5.4°, ATAA 52.7°±4.1°, APST 89.1°±5.9°, APD was (32.9±2.6) mm, LPTS (20.5±2.4) mm, and LTT (40.9±5.7) mm. After grouping by gender, there was no significant difference in PSA between men and women (P>0.05) while there were significant differences in the other indexes between men and women (P<0.05). After grouping by body height, there was no significant difference in ATPT, PSA, APST or ATAA between the 3 groups (1.00 to 1.60 m group, 1.61 to 1.70 m group and ≥1.71 m group) (P>0.05) while there were significant differences in L1, L2, APD, LPTS and LTT between the 3 groups (P<0.05). Conclusions Based on the knee CT images, the primary measures of PCL low tibial tunnel are as follows: the angle between tibial plateau and tibial tunnel is 37.0°±4.5°, and the perpendicular distances from the tibial tunnel entrance and exit point to the tibial plateau are (57.8±7.4) mm and (34.5±3.3) mm, respectively. Gender and body height are the important factors influencing the above measurement outcomes. © 2022 Chinese Journal of Orthopaedic Trauma. All rights reserved.     

震荡流体剪切力通过ERK5信号通路促进成骨细胞增殖

目的探讨震荡流体剪切力(oscillatory shear stress,OSS)通过ERK5信号通路在诱导成骨细胞增殖中发挥的作用。方法对成骨MC3T3-E1细胞进行不同的处理,分为正常组、OSS组、XMD8-92组和OSS+XMD8-92组。采用MTT实验分别测定4组细胞的增殖活性并绘制生长曲线;蛋白免疫印迹法分别检测P-ERK5、ERK5和Cyclin D1等蛋白水平变化。结果 OSS可显著增加成骨MC3T3-E1细胞增殖活性,但此效应可被ERK5高选择性抑制剂XMD8-92阻断。OSS可显著上调Cyclin D1的表达,而XMD8-92可显著下调OSS诱导的Cyclin D1的表达。结论 OSS通过激活ERK5信号通路促进成骨细胞增殖,Cyclin D1是ERK5信号通路下游的重要靶点基因。     

膝关节镜下单双束重建后交叉韧带术后临床疗效的Meta分析

目的 评价膝关节镜下单双束重建后交叉韧带(posterior cruciate ligament,PCL)的临床疗效.方法 检索Pubmed、Embase、The Cochrane Library、中国期刊全文数据库(CNKI)、中国生物医学文献数据库(CBM)、中文科技期刊数据库(VIP),全面检索发表的有关膝关节镜下经胫骨骨道单束、双束重建PCL的随机对照试验(randomized controlled trims,RCT)与非随机对照试验(non-RCT).由2名研究者独立评价并交叉核对纳入文献的方法学质量评价,采用RevMan5.3软件进行统计学分析.结果 共纳入8篇文献,包括4篇RCT,4篇回顾性对照研究,共计323例PCL损伤患者.Meta分析结果显示:膝关节镜下单束和双束重建PCL在Lysholm评分{MD=-3.51,95％ CI[-4.54,-2.48],P＜0.01}、Tegner评分{MD=-0.52,95％ CI[-0.89,-0.14],P=0.007}、IKDC正常与接近正常评分{ OR=0.40,95％ CI(0.19,0.84),P=0.01}、IKDC不正常与严重不正常评分{OR=2.48,95％ CI(1.20,5.15),P=0.01}、膝关节屈曲90°时的后向稳定性评分{MD=0.92,95％ CI(0.18,1.56),P=0.01}方面的Meta分析结果显示差异具有统计学意义;而2组在膝关节屈曲30°时的后向稳定性评分{MD=0.63,95％ CI(-1.63,2.61),P=0.54}、术后并发症发生率{OR =0.60,95％CI(0.22,1.62),P=0.32}方面无统计学差异.结论 关节镜下经胫骨骨道PCL的单束重建优于双束重建,且手术难度较小、损伤较小、骨道位置较易控制,但膝关节屈曲90°时的后向稳定性较双束重建差.