Role of Junction-Mediating and Regulatory Protein in the Pathogenesis of Glucocorticoid-Induced Endothelial Cell Lesions.

OBJECTIVE: Nontraumatic osteonecrosis of the femoral head (ONFH) is one of the most common diseases in orthopaedics. The damage to vascular endothelial (VE) cells caused by glucocorticoids (GC) has been reported as a possible mechanism of pathogenesis for ONFH. Junction-mediating and regulatory protein (JMY), originally identified as a p53 coactivator, plays prominent roles in the DNA damage response and in cell motility. This study aimed to discover the role of JMY in the pathogenesis of GC-induced endothelial cell lesions. METHODS: High-throughput RNA sequencing was performed to identify the differentially expressed genes between GC-treated human umbilical vein endothelial cells (HUVEC) and control cells. JMY knockdown and overexpressing HUVEC lines were treated with GC. Cell proliferation was examined with a survival cell count assay (Cell Counting Kit-8, CCK-8); cell apoptosis was measured by flow cytometry; a scarification assay was used to detect the capability of cell migration; a Transwell chamber assay was done to detect the cell motility . Differential expression of cell protein was detected by western blot. RESULTS: A total of 1561 differential genes were obtained through transcription sequencing, of which 789 mRNA were upregulated and 772 mRNA were downregulated in the GC-treated HUVEC compared with the control cells. CCK-8 assay results showed that: without GC treatment, overexpression or knockdown of JMY did not affect the proliferation activity of HUVEC. In the presence of GC treatment, the proliferation activity of HUVEC in the JMY knockdown group was significantly higher than that in the control group (P < 0.01). The proliferation activity of HUVEC in the overexpression JMY group was significantly lower than that in the control group (P < 0.01). The results of flow cytometry showed that without GC treatment, overexpression or knockdown of JMY did not affect the apoptosis proportion of HUVEC. With GC treatment, the apoptosis proportion of HUVEC in the JMY knockdown group was significantly lower than that in the control group (P < 0.01), and the apoptosis proportion of HUVEC in the overexpression JMY group was significantly higher than that in the control group (P < 0.01). Western blot results showed that with GC treatment, the JMY expression level of HUVEC increased with the reaction time. Moreover, the distribution of JMY was mainly concentrated in the nucleus. The expression level of Bax also increased with the reaction time. With GC treatment, overexpression of JMY could significantly increase the expression of Bax in HUVEC. JMY knockdown could reduce the expression of Bax in HUVEC. In the absence of GC treatment, HUVEC overexpression or knockdown of JMY did not affect the expression of Bax. The results of scarification and Transwell chamber assays showed that: without GC treatment, JMY knockdown could significantly decrease the cell motility and increase the expression level of VE-cadherin in HUVEC; with GC treatment, JMY knockdown in HUVEC had lower cell motility compared with the control group (P < 0.01). CONCLUSION: Glucocorticoids can induce the HUVEC apoptosis, and reduce its proliferation, cell motility. Our results mainly confirmed the role of JMY in the pathogenesis of GC-inducing lesions in HUVEC. GC act on HUVEC, inducing cell damage. Following the event of cell damage, JMY levels upregulate in the nucleus to induce transcription of Bax, triggering apoptosis. JMY can also regulate HUVEC motility via its regulation of VE-cadherin levels.

High failure rate after Beta-tricalcium phosphate grafting for the treatment of femoral head osteonecrosis: a retrospective analysis.

BACKGROUND: Non-vascularized bone grafting is a promising head-preserving technique for younger patients diagnosed as non-traumatic osteonecrosis of the femoral head (NONFH). Among the various types of bone grafting techniques, "light-bulb" procedure grafting with synthetic bone substitute is an attractive option. We aimed to assess the effectiveness of using beta-tricalcium phosphate (ß-TCP) for the treatment of pre-collapse and early post-collapse lesions NONFH. METHODS: From April 2010 to June 2014, 33 patients (47 hips) with NONFH were treated using the afore-mentioned technique. The clinical and radiological outcomes were recorded and compared statistically between pre- and post-operation. Harris hip score (HHS) was used to evaluate the clinical results, and Association Research Circulation Osseous (ARCO) stage was applied to assess the radiological outcomes. RESULTS: The 5-years survival rate of using ß-TCP grafting was accounting for 25.5%. HHS was decreased from 78.47 to 52.87 points, and a very significant worsening of radiological results were revealed (P <  0.05). Two hips collapsed more than 2 mm were awaiting for THA, and 33 of the 47 hips had converted to THAs in an average time to failure of 24.24 months postoperatively. Meanwhile, only 4 hips survived without collapse, and 8 hips collapsed less than 2 mm. After surgery, the time onset of head collapse was 3.65 months on average, and the first conversion to THA was performed at 5 months postoperative. CONCLUSIONS: Our results suggest that "light-bulb" procedure grafting with ß-TCP sticks presented with a high failure rate in the early postoperative period. It is not proposed for the treatment of pre-collapse and early post-collapse lesions NONFH.

Selective medial soft tissue release combined with tibial reduction osteotomy in total knee arthroplasty.

BACKGROUND: To obtain the correct coronal alignment and balancing in flexion and extension, we established a selective medial release technique and investigated the effectiveness and safety of the technique during primary total knee arthroplasty (TKA). METHODS: Four hundred sixty-six primary TKAs with varus deformity were prospectively evaluated between June 2013 and June 2015. A knee joint position similar to Patrick's sign was used to release the medial structure. The medial release technique consisted of release of the capsule and the deep medial collateral ligament (dMCL) (step1), selective release of superficial medial collateral ligament (sMCL) or posterior oblique ligament (POL) (step 2), and selective tibial reduction osteotomy (step 3). Improvement of medial joint gap at each step and other clinical outcomes were evaluated. RESULTS: Among the 466 knees, symmetrical gaps could be achieved by the limited release of the capsule and the dMCcL in 276 (59%) knees. One hundred fifty-two (33%) required additional sMCL release with 2-5 cm from the joint line distally or POL release. Thirty-eight (8%) necessitated an additional tibial reduction osteotomy. Anterior-medial release and 4-mm medial osteotomy contributed to more improvement of medial gap in flexion than in extension (each p < 0.01). Posteromedial release and posteromedial osteotomy contributed to more improvement in extension than in flexion (each p < 0.01). No specific complication related to our technique was identified. CONCLUSION: The technique of the tibial reduction osteotomy combined with medial soft structure release using Patrick's sign is effective, safe, and minimally invasive to obtain balanced mediolateral and extension-flexion gaps in primary TKA.

[Case-control study on individual osteotomy instrument and conventional total knee arthroplasty for the treatment of knee osteoarthritis].

OBJECTIVE: To compare clinical efficacy of individual osteotomy instrument and total knee arthrolplasty (TKA) in treating patients with knee osteoarthritis. METHODS: From June 2014 to December 2014, 40 patients with unilateral knee osteoarthritis were randomly divided into two groups and 20 cases were in each group. One group (individual group) were treated with TKA with individual osteotomy instrument,including 5 males and 15 females with an average age of (67.3 ± 6.5) years old; 8 cases on the left side and 12 cases on the right side. Another group (conventional group) were treated with conventional TKA , including 6 males and 14 females with an average age of (66.8 ± 7.3) years old; 9 cases on the left side and 11 cases on the right side. Operative time, blood loss, postoperative HSS score at 6 months, and changes of mechanical alignment before and after operation were analyzed. RESULTS: Operative time in individual group was (79.3 ± 4.7) min, and (83.5 ± 3.2) min in conventional group; blood loss in individual group was (287.1 ± 24.9) ml and (363.4 ± 47.2) ml in conventional group, there were statistical differences between two groups in these two items. There was no significant difference in postoperative HSS score at 6 months between individual group (84.8 ± 3.2) and conventional group (84.2 ± 2.5). Postoperative limb alignment in individual group was (2.8 ± 0.6)°, and (2.8 ± 0.6)° in conventional group, with no significant difference between two groups. CONCLUSION: TKA with individual osteotomy instrument could reduce operative time and blood loss, but there was no differences in knee function, changes of mechanical alignment compared with TKA.

Simultaneous determination of tedizolid and linezolid in rat plasma by ultra performance liquid chromatography tandem mass spectrometry and its application to a pharmacokinetic study.

A sensitive and rapid ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed to determine tedizolid and linezolid in rat plasma simultaneously. Chromatographic separation was carried out on an Acquity UPLC BEH C18 column and mass spectrometric analysis was performed using a XEVO TQD triple quadruple mass spectrometer coupled with an electrospray ionization (ESI) source in the positive ion mode. Multiple reaction monitoring (MRM) mode was used for quantification using target fragment ions m/z 371.4→343.2 for tedizolid, and m/z 338.3→56.1 for linezolid. This assay method has been fully validated in terms of selectivity, linearity, recovery and matrix effect, accuracy, precision and stability. The linearity of this method was found to be within the concentration range of 5-5000ng/mL for tedizolid, and 10-10,000ng/mL for linezolid in rat plasma, respectively. Only 3.0min was needed for an analytical run. This assay was used to support a preclinical study where multiple oral doses were administered to rats to investigate the pharmacokinetics of tedizolid and linezolid.

[Research on the reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in total knee arthroplasty].

OBJECTIVE: To study on the reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in total knee arthroplasty (TKA) the rotational alignment reference bony landmarks of the proximal tibial component on magnetic resonance image (MRI) were measured. METHODS: From January 2010 to December 2013, 80 normal knees of Chinese volunteers including 35 males and 45 females with an average age of (35.4±6.1) years were reviewed. The images of the knees were obtained by MRI. The surgical epicondylar axis (STEA) was identified in the femoral transverse sections and then was projected to the side of tibia, forming the SETA'. A line connecting the medial border of the patellar tendon and the middle of the posterior cruciate ligament insertion (Akagi line) and its vertical line (AK), as well as a line connecting the medial 1/3 of the patellar tendon and the middle of the posterior cruciate ligament insertion and its vertical line (AP), were identified in the tibial transverse sections. The angles were measured between the AK, AP and STEA'. RESULTS: The angle between AK and STEA' was (0.59±2.07)°, and there was no significant difference between the two lines (t=-2.54, P=0.13). The mean angle between AP and STEA' was (3.21±2.04)°, and there was a significant difference between the two lines (t=14.05, P<0.05). There was a significant difference between the AK and AP (t=-11.68, P<0.05). CONCLUSION: The reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in TKA is good.

[Arthroscopic treatment of symptomatic anterior cruciate ligament cysts of the knee].

OBJECTIVE: To explore the clinical symptom and effect of arthroscopic treatment of symptomatic anterior cruciate ligament (ACL) cysts of the knee. METHODS: Clinical data from 12 symptomatic ACL cysts patients from January 2005 to December 2010 were retrospectively analyzed,including 8 males and 4 females,with an average age of (33.7±9.5) years old (ranged, 19 to 53 years old). The locations were the left knee in 5 cases and the right knee in 7 cases. The disease duration ranged from 3 to 48 months,with a mean of (15.8±13.2) months. All cysts were arthroscopically resected. Range of motion was measured preoperatively and postoperatively, and Lysholm scoring system was used to evaluate the knee function. RESULTS: All the incisions healed by first intention, and no complications occurred. Twelve patients were followed up for an average of (32.3±6.6) months(ranged, 24 to 48 months). The symptoms of arthralgia,swelling and interlocking of the affected knees disappeared. There was no recurrence during the follow-up. There were significant differences in the range of motion and Lysholm score between pre-operation and post-operation. CONCLUSION: Arthroscopic surgery, showing its advantages of minimal invasion and rapid recovery,is an effective measure in the treatment of ACL cysts.

[Application of orientation to the mechanical alignment of lower limbs in operation of high tibial osteotomy].

OBJECTIVE: To evaluate the effects of orientation to the mechanical alignment of lower limbs in high tibial osteotomy (HTO). METHODS: From March 2005 to July 2010, the data of 57 patients (63 knees) with medial compartment osteoarthritis were retrospectively analyzed. There were 24 males and 33 females with an average age of 52 years (ranged, 34 to 68). HTO was used in all the patients, and with wire the exact orientation to the mechanical alignment of lower limbs was performed in order to obtain good angle of intercepted bone. X-rays of full-length lower limbs were done at the 3rd month after operation and final follow-up, in which femorotibial angle would be observed. Clinical results were evaluated according to Hospital for Special Surgery knee scores (HSS) including pain, function, activities, myodynamia, deformity and instability. RESULTS: All patients were followed up from 24 to 60 months with an average of 36.7 months. All osteotomy site achieved radiographic healing. The femorotibial angle was corrected from preoperative (182.8 +/- 2.9) degrees to postoperative (167.6 +/- 2.5) degrees and (168.1 +/- 2.5) degrees at final follow-up (compared with preoperative data, P < 0.01). Pain relieved and genu valgum recovered. HSS score improved from preoperative 69.5 +/- 7.1 to postoperative 91.1 +/- 4.9 and 92.2 +/- 5.6 at final follow-up. According to HSS standard, 43 knees got excellent results, 18 good and 2 fair. CONCLUSION: The orientation to mechanical alignment of lower limbs using wire during operation of HTO is a good method in correcting femorotibial angle and treating medial compartment osteoarthritis of the knee. Moreover, the method is simple and precise for orthopedist.

[Surgical treatment of displaced intra-articular fractures of the calcaneus in elderly patients].

OBJECTIVE: To study the clinical effects of surgical treatment of displaced intra-articular fractures of the calcaneus in elderly patients, and to discuss the operative indications. METHODS: From January 2000 to December 2007, 24 elderly patients with 26 fractures underwent open reduction and internal fixation for a displaced intra-articular fracture of calcaneus, which included 18 feet of 18 males and 8 feet of 6 female, with an average age of 67 years (range, 60 to 75 years). According to Sanders classification based on CT scanning, 13 fractures were rated as type II, 12 as type III and 1 as type IV. Böhler angle and Gissane angle were measured preoperatively and postoperatively and foot function was assessed with Maryland foot score system. RESULTS: Twenty-four cases with 26 feet were followed up for an average of 18.4 months (range, 12 to 26 months). Mean Böhler angle was (10.4 +/- 8.2) degrees preoperatively and (27.8 +/- 7.4) degrees postoperatively and mean Gissane angle was (136.5 +/- 10.3) degrees preoperatively and (124.3 +/- 4.2) degrees postoperatively. The difference between preoperative and postoperative values was found with statistically significant (P < 0.05). The results were excellent in 5 feet, good in 16 feet, fair in 4 feet and poor in 1 foot. There were 3 cases of wound necerosis, 2 cases of wound infection, 1 case of sural nerve injury and 6 cases of posttraumatic subtalar arthritis complications. CONCLUSION: Good clinical result could be obtained with surgical treatment in elderly patients with displaced intra-articular fractures of the calcaneus. Open reduction appears to be an acceptable method of treatment for displaced calcaneal fractures in elderly patients if they have good general conditions.

Effects of rhBMP-2 on cortical strut allograft healing to the femur in revision total hip arthroplasties: an experimental study.

We have studied the effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) on cortical strut allograft healing and remodelling in revision hip arthroplasty. Thirty adult New Zealand rabbits underwent bilateral onlay allograft strut procedures to the femur using wires. The left femur (experimental side) received the rhBMP-2 device (1.0-mg rhBMP-2/gelatin composites) interposed between the allograft and host bone, while the right side was grafted with an allograft strut as the control. The femurs and implants were retrieved at 4, 6, and 8 weeks postoperatively. The healing of cortical strut grafts to the femur was enhanced dramatically by the addition of the rhBMP-2 device in radiographic examination, contact radiographic examination, non-decalcification sections, fluorescence tag, and computer-aided image analysis. The remodelling of cortical strut allograft was also accelerated. The new bone formation ratio and radiographic scores of the experimental side were also much higher than the control side at all times. Strut healing with the rhBMP-2 device at 4 weeks postoperatively was superior to the healing in control sides at 8 weeks. Our findings showed that the rhBMP-2 device improved and accelerated the course of cortical strut allograft healing and remodelling with host bone.

Effect of dehydroepiandrosterone on cartilage and synovium of knee joints with osteoarthritis in rabbits.

The aim of this study was to investigate the effects of intra-articular injection of dehydroepiandrosterone (DHEA) on cartilage and synovium of knee joints with osteoarthritis (OA) in rabbits and the underlying mechanism. Forty rabbits underwent unilateral anterior cruciate ligament transaction and were divided into two groups. Rabbits were injected with 100 mumol/l DHEA dissolved in the dimethylsulphoxide (DMSO) in the knee joints 5 weeks after transaction, once a week for 5 weeks. Rabbits injected with DMSO under the same condition were served as a control. All rabbits were killed 1 week after the last injection. The knee joints were evaluated by gross morphology, histology, and gene expression analysis. Gross morphologic inspection and histological evaluation showed that the DHEA group appeared less damage in cartilage and synovium as compared with the control. Gene expression analysis revealed that the mRNA expression of matrix metalloproteinase-3 (MMP-3) in cartilage and synovium decreased significantly in the DHEA group and that of tissue inhibitor of metalloproteinase-1 (TIMP-1) increased. No significant difference of interleukin-1 beta (IL-1beta) mRNA expression was found in the cartilage between two groups while the mRNA expression of IL-1beta in the synovium was largely suppressed in the DHEA group. The study suggests that DHEA plays a protective role against cartilage degradation and synovium inflammation in rabbits with OA. This role may be achieved through the regulation of the MMP-3, TIMP-1, and IL-1beta gene expression in the cartilage and synovium.