Objective To investigate the feasibility of NR2B small interference RNA(NR2B siRNA)carried by water-soluble lipopolymer(WSLP)for treatment of neuropathic pain in rats.Methods One hundred healthy male SD rats weighing 180-200 g were randomly divided into 5 groups(n=20 each):normal control group (group C),sham operation group(group S),neuropathic pain group(group NP),group WSLP-NR2B siRNA (group W)and group WSLP-negative NR2B siRNA(group WN).Neuropathic pain was induced by partial ligation of sciatic nenre.WSLP-NR2B siRNA complex was formed by binding WSLP and NR2B siRNA.Normal saline.WSLP-NR2B siRNA complex and WSLP-negative NR2B siRNA 20μl were injected intrathecally after operation in NP,W and WN groups respectively.Mechanical withdrawal threshold(MWT)and thermal withdrawal duration (TWD)were measured before(baseline)and at 3,7,14 and 21 days after operation.Ten animals in each group were sacrificed on the 3rd day after operation and the lumbar segment(L4-6)of the dorsal root ganglia was removed for determination of the expression of NR2B mRNA and protein using RT-PCR and Western blot analysis.Results Sciatic nerve ligation significantly decreased MWT and prolonged TWD and increased NR2B mRNA and protein expression in group NP as compared with group C.WSLP-NR2B siRNA complex significantly reduced sciatic nerve ligation-induced hyperalgesia and decreased NR2B mRNA and protein expression in group W as compared with group NP.Conclusion WSLP not only mediates NR2B siRNA successfully and inhibits the expression of NR2B,but also reduces neuropathic pain in rats.

Objective:To investigate the clinical efficacy of a medial support plate and a row of screws in the treatment of Schatzker type Ⅳ tibial plateau fracture involving the postero-lateral condyle.Methods:A retrospective analysis was performed of the data of 26 patients who had been admitted to Department of Orthopedic Trauma, Honghui Hospital Affiliated to Xi'an Jiaotong University for Schatzker type Ⅳ tibial plateau fracture involving the postero-lateral condyle from December 2015 to December 2020. There were 17 males and 9 females, aged from 19 to 51 years (average, 36.1 years). All their fracture lines involved the postero-lateral condyle and all fractures were fixated with a medial support plate and a row of screws via one medial and one lateral incisions. Recorded were the operation time, hospital stay, blood loss, incision length, fracture healing, complications, quality of knee joint reduction and knee joint function at the last follow-up.Results:The length of hospital stay ranged from 8 to 16 days, averaging 10.4 days. The 26 patients were followed up for 8 to 18 months, with an average of 14.3 months. All the fractures got united after 11 to 17 weeks (average, 13.7 weeks). During the follow-up, no reduction loss, internal fixation failure or surgical complications were observed. Rasmussen radiographic scores at the last follow-up ranged from 11 to 18 points, averaging 16.1 points. The range of motion of the knee joint ranged from 0° to 140°, averaging 120.8°. The Rasmussen scores of the knee function ranged from 14 to 28 points, averaging 24.4 points.Conclusion:In the treatment of Schatzker type Ⅳ tibial plateau fracture involving the postero-lateral condyle, the use of a medial support plate and a row of screws can achieve satisfactory clinical results.