Objective To monitor the autophagy in osteosarcoma cells by constructing three rLC3B fusion expression vectors,respectively.Methods Rat LC3B gene sequence was amplified by PCR and cloned into pEGFP-C 1 and pmCherry-C1 to construct the fusion expression vector of pEGFP-rLC3B and pmCherry-rLC3B.Subsequently,the EGFP-rLC3B sequence was obtained by PCR with the pEGFP-rLC3B as a template,and cloned into pmCherry-C 1,so the pmCherry-EGFP-rLC3B fusion expression vector was constructed.Three plasmids were transfected into U-2OS cells,and the starvation or Rapamycin was adopted to induce autophagy or the chloroquine or Baf-A1 was used to inhibit autophagy,to verify the above plasmids' function in autophagy detection by laser scanning confocal microscopy.Western blot was used to detect the endogenous LC3B and exogenous EGFPrLC3B,pmCherry-rLC3B and mCherry-EGFP-rLC3B,and to verify the correct expression of exogenous rLC3B and their function of autophagy detection.Finally,cleaved free EGFP was detected by western blot to evaluate the level of autophagic degradation.Results Three fusion expression vectors were constructed successfully through sequencing and restriction enzyme digestion validation.The starvation or Rapamycin was adopted to induce autophagy or the chloroquine or Baf-A 1 was used to inhibit autophagy in transfected U-2OS cells.Clear autophagosomes and autolysosomes were observed by laser scanning confocal microscopy.Endogenous LC3B and exogenous EGFP-rLC3B,pmCherry-rLC3B and mCherry-EGFP-rLC3B were detected through western blot.Finally,western blot verified that the expression of cleaved free EGFP was significantly up-regulated with the increase of starvation time.12 h group increased 1.05 times than the control group and 24 h group increased 1.56 times,showing that the levels of autophagic degradation increased.Conclusion EGFP-rLC3B can be used to detect autophagosome and evaluate the level of autophagic degradation.mCherry-rLC3B can be used to detect autophagosome and autolysosome,but can't distinguish autophagosome from autolysosome.The pmCherry-EGFP-rLC3B has an advantage in the detection of autophagic flux which can distinguish autophagosome from autolysosome.

Objective To study the short-term clinical outcomes of unicompartmental knee arthroplasty for medial compartmental knee osteoarthritis,and to compare 2 kinds of unicompartmental prosthesis.Methods From March 2010 to June 2013,data of 43 patients underwent unicompartmental knee arthroplasty (UKA) were retrospectively analyzed.17 patients (17knees) used rotating platform prosthesis,and 26 patients (28 knees) used fixed bearing prosthesis.There were 7 males (7 knees)and 9 females (10 knees) in rotating platform group,with an average age of 64.1 years (range,54-82 years);while 10 males (10knees) and 17 females (18 knees) in fixed bearing group,with an average age of 62.2 years (range,43-79 years).All patients presented signs of narrowed medial joint space,medial tenderness and pain on weight-bearing.X-ray and MRI were used for documenting joint narrowing and cartilage defect.The pain and the knee functions were recorded both pre and post-operatively with knee society score (KSS),2 cases of simultaneous anterior cruciate ligament (ACL) reconstruction were assessed with TegnerLysholm knee scoring scale as well.Results All 43 patients were followed up for 6 month to 37 months,and the average duration was 21.1 months.There were no dislocations,joint infection,deep venous thrombosis,prosthetic loosening,etc.The KSS in rotating platform group was 56.11 ±9.51 preoperatively,and 92.23±5.46 postoperatively.While the KSS in fixed bearing group was 57.11 ±9.56,and 93.69±6.37,respectively.There were statistical differences comparing between preoperative and postoperative KSS knee scores.There was no significant difference in KSS scores between rotating platform group and fixed bearing group.Conclusion Unicompartmental knee arthroplasty is a less invasive and effective method for knee osteoarthritis in medial compartment with less complications.There was no significant difference in clinical outcomes between rotating platform and fixed bearing design in terms of patients' satisfactory rate,clinical and functional outcomes in this short-term follow-up study.

Objective: To investigate the clinical effects of primary revision after artificial hip replacement and causes of revision surgery. Methods: A total of 344 patients who underwent revision surgery after total hip arthroplasty (THA) and artificial femoral head replacement from January 2010 to December 2016 were retrospectively analyzed. There were 141 males and 203 fe-males, with a mean age 65.64±10.81 years (28-87 years). A total of 351 hip revisions were performed in 344 patients with 7 pa-tients in bilateral revisions. All patients were followed up for 60.38±22.75 months (24-105 months). All patients with periprosthet-ic infection underwent two-stage revision after prosthesis placement, and all others underwent one-stage revision. The clinical out-comes of revision surgery were assessed with the Harris hip score and the survival rate of the revision prosthesis. According to the duration from artificial hip replacement to revision surgery, all patients were divided into early revision (less than 5 years) and late revision (more than 5 years) groups. They were also divided into two groups according to the age of the patient in revision sur-gery: >55-year-old and ≤55-year-old groups. The causes of revision, hip reoperation and re-revision were recorded. Results: In the 351 hip revisions, a total of 238 (67.8%) had aseptic loosening, 41 (11.7%) periprosthetic fractures, 30 (8.5%) periprosthetic infection, 23 (6.6%) recurrent dislocation and 19 (5.4%) the eccentric liner wear. The infection rate was significantly higher in the early revision group (21.1%) than that in the late revision group (4.2%) (χ²=24.443, P<0.001). The aseptic loosening rate was sig-nificantly higher in the late revision group (72.4%) than that in the early revision group (54.4%) (χ²=9.899, P=0.002). Sixteen pa-tients underwent hip surgery after revision, including 6 recurrent dislocations, 4 aseptic loosening, 3 periprosthetic fractures, and 3 periprosthetic infections. Eight of them underwent revision surgery, including 4 cases of aseptic loosening, 2 cases of periprosthet-ic fractures, and 2 cases of recurrent dislocation. The duration from the primary revision to the second revision was 22.1±10.0 months (1-75 months). The 5-year and 8-year survival rates of the revision prostheses were 99.3%[95%CI(98.3%, 100.3%)] and 92.6% [95%CI(87.1%, 98.1%)], respectively. The proportions of prosthetic infection and eccentric liner wear in the ≤55-year-old group were significantly higher than those in the >55-year-old group (χ²=3.981, P=0.046; χ²=5.226, P=0.022), while the propor-tion of aseptic loosening in the >55-year-old group was significantly higher than that in the ≤55-year-old group (χ²=5.254, P=0.022). The 8-year survival rates of the revision prostheses of ≤55-year-old group and >55-year-old group were 76.8% [95%CI(50.5%, 103.1%)] and 95.4% [95%CI(91.1%, 99.7%)], respectively. Conclusion Young patients have a higher risk of re-revi-sion after revision THA.