Negative pressure wound therapy reduces the incidence of postoperative wound dehiscence and surgical site infections after total knee arthroplasty in patients with obesity.

Obesity is a risk factor for total knee arthroplasty (TKA). Wound dehiscence and surgical site infections (SSIs) are the main complications of TKA in patients with obesity. They can profoundly affect patients because they often require readmission, additional surgical interventions, lengthy intravenous antibiotic administration, and delayed rehabilitation. Negative pressure wound therapy (NPWT) exposes the wound site to negative pressure, resulting in the improvement of blood supply, removal of excess fluid, and stimulation of cellular proliferation of granulation tissue. This study aims to assess the incidence of wound dehiscence and SSIs in patients with obesity undergoing TKA after the routine use of NPWT. This sduty enrolled adult patients with obesity who underwent TKA within 8 years. A total of 360 adult patients with obesity (NPWT: 150, non-NPWT: 210) underwent TKA, and the baseline characteristics were similar between the 2 groups. Compared with the non-NPWT group, the NPWT group had a 50% lower incidence of wound dehiscence (3.33% vs 9.52%; P < .05) and a significantly lower incidence of SSIs (11.33% vs 25.24%; P < .05), including prosthetic joint infection (4.0% vs 10.0%; P < .05) and superficial wound infection (7.33% vs 15.24%; P < .05). In addition, the NPWT group had a lower need to return to the operating room for new interventions for any reason (2.67% vs 9.05%; P = .0107) than the non-NPWT group. Conventional incision NPWT can significantly reduce the incidence of wound dehiscence and SSIs in patients with obesity after TKA.

Resveratrol prevents steroid-induced osteonecrosis of the femoral head via miR-146a modulation.

The purpose of this study was to investigate the possible use of resveratrol (Res) to reverse abnormal osteogenesis/osteoclastogenesis activity that occurs during femoral head osteonecrosis and to explore the detailed mechanisms. Application of Res to bone marrow-derived mesenchymal stem cells in vitro promoted survival, inhibited apoptosis, and downregulated expression of reactive oxygen species expression. Moreover, Res application was associated with elevated microRNA-146a (miR-146a) expression, osteogenic differentiation, and suppressed osteoclastic differentiation, which were markedly reversed by miR-146a inhibitor. Histopathological observations and micro-computed tomography scanning results indicated that the Res-treated group had lower incidence of osteonecrosis and better bone microstructure than the untreated group. Res inhibited osteoclastogenesis through altering the levels of sirtuin1 (Sirt1), nuclear transcription factor-κB (NF-κB), and receptor activator of NF-κB ligand (RANKL). Simultaneously, Res treatment improved bone formation and increased ß-catenin and runt-related transcription factor 2 (Runt2) expression levels, while reducing forkhead box class O (FOXO) family protein levels. The results of our study suggest that Res prevents steroid-induced osteonecrosis by upregulating miR-146a, and thereby stabilizes osteogenesis/osteoclastogenesis homeostasis via Wnt/FOXO and Sirt1/NF-κB pathways.

Oral treatment with glycyrrhizin inhibits NLRP3 inflammasome activation and promotes microglial M2 polarization after traumatic spinal cord injury.

The inflammatory response induced by traumatic spinal cord injury (SCI) involves the activation of NLRP3 inflammasomes, which are closely related to the activation of microglia. Microglial polarization between M1/M2 phenotypes is a pivotal regulatory factor in neuroinflammatory responses to traumatic SCI-induced secondary injuries, and altering this polarization could be beneficial. Glycyrrhizin is a neuroprotective agent with a potent anti-inflammatory property in different neurological disorders and could potentially be useful in SCI. In this study, we investigated the potency of oral treatment with glycyrrhizin to reduce inflammation and improve functional recovery after traumatic SCI by inhibiting NLRP3 inflammasome activation and promoting microglial M2 polarization. After inducing traumatic SCI by dropping a 10 g impactor on the T9 and T10 spinal segments of male Sprague-Dawley rats, the animals were given glycyrrhizin orally immediately after injury and every 12 h for the next 3 d. Behavioral scores improved in glycyrrhizin-treated animals compared to the SCI group. The functional improvement in glycyrrhizin-treated rats paralleled the decreased expression of NLRP3 inflammasome components, such as ASC, NLRP3, and cleaved caspase-1, as well as IL-1ß and IL-18. At the histopathological level, oral treatment with glycyrrhizin diminished the SCI-enhanced production of Iba-1+CD86+ cells (M1 microglia) but improved the release of Iba-1+CD206+ cells (M2 microglia). Likewise, oral therapy with glycyrrhizin significantly enriched the protein expression levels of M2 microglia-related markers (CD206 and Arg-1) but reduced those of M1 microglia-related markers (CD86 and iNOS) in the injured spinal cord. These findings support and extend the knowledge on post-traumatic SCI glycyrrhizin-mediated neuroprotection. Glycyrrhizin's regulation of NLRP3 inflammasome activation and microglial polarization might be a new approach to understanding the anti-inflammatory potency of glycyrrhizin.

[Total arthroscopic internal drainage technique for the treatment of popliteal cyst].

OBJECTIVE: To compare the clinical effects of total arthroscopic internal drainage and arthroscopic combined with posterior small incision in the treatment of popliteal cyst. METHODS: From January 2015 to January 2017, 60 patients with popliteal cyst were treated, including 29 males and 31 females, aged 30 to 65(47.8±2.5) years old, with a course of disease (8.5±4.2) months. Among them, 30 cases received total arthroscopic internal drainage for popliteal fossa cyst(total arthroscopic group), 30 cases received arthroscopic combined with posterior small incision for popliteal fossa cyst(arthroscopic combined with small incision group). The operation time, intraoperative bleeding volume, incision length, Rauschning and Lindgren grade 0 recovery rate and Lysholm score were compared between the two groups. RESULTS: Twenty-nine patients in total arthroscopy group were followed up, and 28 patients in arthroscopy combined with small incision group were followed up for 8 to 20(12.8±2.1) months. Operation time: total arthroscopic group(45.32±5.71) min, arthroscopic combined small incision group (44.56±3.85) min; Rauschning and Lindgren grade 0 recovery: 23 cases in total arthroscopic group, 22 cases in arthroscopic combined small incision group; postoperative Lysholm score: total arthroscopic group 84.5±11.2, arthroscopic combined small incision group 83.2±12.7; there was no significant difference between the two groups(P>0.05). Intraoperative bleeding volume: total arthroscopic group(5.32±1.25) ml, arthroscopic combined small incision group(20.75±8.18) ml; incision length: total arthroscopic group (1.51±0.34) cm, arthroscopic combined small incision group (7.34±0.75) cm; the difference between the two groups was significant(P<0.05). At the last follow-up, the knee joint was examined by magnetic resonance imaging, and no recurrence of cyst was found. CONCLUSIONS: Total arthroscopic internal drainage and arthroscopic combined with posterior small incision technique for popliteal fossa cyst with intra-articular lesions have the same clinical effect, but less trauma and faster recovery.

The effectiveness and safety of 3-dimensional printed composite guide plate for atlantoaxial pedicle screw: A retrospective study.

This study aims to evaluate the effectiveness and safety of the application of a 3-dimensional (3D)-printed composite guide plate for atlantoaxial pedicle screw.This was a retrospective study. A total of 43 atlantoaxial dislocation patients admitted in our hospital between January 2014 and October 2016 were retrospectively analyzed. According to the different methods of operation, patients were divided into 2 groups: 3D-printed plate group (n = 19) and traditional fixation group (n = 24). Placement time, operation duration, fluoroscopy number, intraoperative bleeding volume, and the neck and shoulder pain visual analog scale and Japanese Orthopaedic Association cervical nerve function scores were compared between pre- and postoperation.Differences in general data between these 2 groups were not statistically significant (P > .05). For patients in the 3D-printed plate group, a total of 68 assisting screws were placed at the pedicle, the accuracy rate of screw placement was 94.1%, placement time was 2.2 ±â€Š0.4 minutes, fluoroscopy number was 4.6 ±â€Š1.1 times, operation duration was 197 ±â€Š41 minutes, and intraoperative bleeding volume was 395 ±â€Š64 mL. In the traditional fixation group, a total of 76 screws were placed at the pedicle of patients, the accuracy rate of screw placement was 76.3%, placement time was 3.4 ±â€Š0.7 minutes, fluoroscopy number was 9.4 ±â€Š2.7 times, operation duration was 245 ±â€Š67 minutes, and intraoperative bleeding volume was 552 ±â€Š79 mL. Differences in accuracy rate, placement time, fluoroscopy number, operation duration, and intraoperative bleeding volume between these 2 groups were statistically significant (P < .05).The effectiveness and safety of 3D-printed composite guide plate for atlantoaxial pedicle screw were better than traditional method.

Muscone exerts protective roles on alcohol-induced osteonecrosis of the femoral head.

Long-term alcohol abuse causes musculoskeletal disorders, among of which, alcohol-induced osteonecrosis of the femoral head (ONFH) is of concern due to its significant and severe complications. A variety of methods have been attempted to prevent alcohol-induced ONFH, and monomers extracted from Chinese herbs might benefit the disease profoundly. In the current study, muscone, the main ingredient of musk, was used to prevent alcohol-induced ONFH. In vitro, ethanol was used to affect the potential of osteogenesis and proliferation of human bone mesenchymal stem cells (hBMSCs), and beneficial role of muscone was investigated on hBMSCs. In vivo, following the establishment of alcohol-induced ONFH, muscone was employed to treat the diseased rats, which were analyzed by micro-CT scanning and a series of histologic staining. As a result, we found ethanol could significantly suppress osteogenic differentiation of hBMSCs, while muscone held the potential to promote ALP activity and mRNA expressions of COL1 and OCN under ethanol treatment. Meanwhile, imaging analysis revealed muscone could restore BV/TV ratio and bone mineral density of the necrotic femoral head, and the protective role of muscone on alcohol-induced ONFH was further confirmed by histologic examinations. Our study confirmed the protective effect of muscone against alcohol-induced ONFH both in vitro and in vivo. Therefore, muscone may be considered as a valuable therapeutic natural drug for alcohol-induced ONFH in humans.

Effects of periarticular injection on analgesic effects and NSAID use in total knee arthroplasty and total hip arthroplasty

OBJECTIVES: This study examined periarticular multimodal drug injection and the use of nonsteroidal anti-inflammatory drugs for an early analgesic effect after total knee arthroplasty and total hip arthroplasty. Patient satisfaction and benefits from the treatment were also assessed. METHODS: A total of 110 patients who were scheduled to undergo total knee arthroplasty and 86 patients who were scheduled to undergo total hip arthroplasty were divided into two groups, the study group and the control group. The study group received a periarticular multimodal drug injection during surgery. The control group received an equal volume of normal saline. All patients received an analgesia pump and a moderate dose of nonsteroidal anti-inflammatory drugs. Resting and motion Numeric Rating Scale scores, the Western Ontario and McMaster Universities Arthritis Index, knee or hip joint range of motion, length of postoperative hospital stay, patient satisfaction, total nonsteroidal anti-inflammatory drug consumption and side effects were recorded. RESULTS: Both study groups exhibited significant improvement in pain Numeric Rating Scale scores during rest and exercise several days after the surgery. The range of joint motion was greater in the study group, and the length of postoperative hospital stay was shorter than that in the control group. Patients in the study group consumed fewer nonsteroidal anti-inflammatory drugs and reported greater satisfaction with surgery. CONCLUSION: Intraoperative periarticular multimodal drug injection significantly relieved pain after surgery and reduced nonsteroidal anti-inflammatory drug consumption. These patient had a better postoperative experience, including satisfaction and rehabilitation.

Patient-specific core decompression surgery for early-stage ischemic necrosis of the femoral head.

INTRODUCTION: Core decompression is an efficient treatment for early stage ischemic necrosis of the femoral head. In conventional procedures, the pre-operative X-ray only shows one plane of the ischemic area, which often results in inaccurate drilling. This paper introduces a new method that uses computer-assisted technology and rapid prototyping to enhance drilling accuracy during core decompression surgeries and presents a validation study of cadaveric tests. METHODS: Twelve cadaveric human femurs were used to simulate early-stage ischemic necrosis. The core decompression target at the anterolateral femoral head was simulated using an embedded glass ball (target). Three positioning Kirschner wires were drilled into the top and bottom of the large rotor. The specimen was then subjected to computed tomography (CT). A CT image of the specimen was imported into the Mimics software to construct a three-dimensional model including the target. The best core decompression channel was then designed using the 3D model. A navigational template for the specimen was designed using the Pro/E software and manufactured by rapid prototyping technology to guide the drilling channel. The specimen-specific navigation template was installed on the specimen using positioning Kirschner wires. Drilling was performed using a guide needle through the guiding hole on the templates. The distance between the end point of the guide needle and the target was measured to validate the patient-specific surgical accuracy. RESULTS: The average distance between the tip of the guide needle drilled through the guiding template and the target was 1.92±0.071 mm. CONCLUSIONS: Core decompression using a computer-rapid prototyping template is a reliable and accurate technique that could provide a new method of precision decompression for early-stage ischemic necrosis.

HSYA alleviates secondary neuronal death through attenuating oxidative stress, inflammatory response, and neural apoptosis in SD rat spinal cord compression injury.

BACKGROUND: Hydroxysafflor yellow A (HSYA) is a major active component of yellow pigment extracted from safflowers; this compound possesses potent neuroprotective effects both in vitro and in vivo. However, underlying mechanism of HSYA is not fully elucidated. The present study investigated the protective effects of HSYA in rat spinal cord compression injury model and related mechanisms involved. METHODS: Sprague-Dawley rats were divided as Sham, Control, and HSYA groups (n = 30 per group). Spinal cord injury (SCI) model was induced by application of vascular clips (force of 50 g, 1 min) to the dura at T9-T10 level of vertebra. Injured animals were administered with either HSYA (8 mg/kg at 1 and 6 h after injury, then 14 mg/kg, for a total of 7 days at 24-h time intervals) or equal volume of saline by intraperitoneal injection. RESULTS: From this experiment, we discovered that SCI in rats resulted in severe trauma, which is characterized by tissue damage, lipid peroxidation, neutrophil infiltration, inflammation mediator release, and neuronal apoptosis. However, HSYA treatment significantly reduced the following: (1) degree of tissue injury (histological score) and edema; (2) neutrophil infiltration (myeloperoxidase activity); (3) oxidative stress (superoxide dismutase, malondialdehyde, and nitric oxide); (4) pro-inflammatory cytokine expression (tumor necrosis factor-α, interleukin-6, inducible nitric oxide synthase, cyclooxygenase-2); (5) nuclear factor-κB activation; (6) apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling staining and cysteine-aspartic protease-3 activity). Moreover, in a separate set of experiments, we clearly demonstrated that HSYA treatment significantly ameliorated recovery of limb function (as evaluated by Basso, Beattie, and Bresnahan behavioral recovery scores). CONCLUSIONS: Treatment with HSYA restrains development of oxidative stress, inflammation response, and apoptotic events associated with SCI of rats, demonstrating that HSYA is a potential neuroprotectant for human SCI therapy.

Effects of periarticular injection on analgesic effects and NSAID use in total knee arthroplasty and total hip arthroplasty.

OBJECTIVES: This study examined periarticular multimodal drug injection and the use of nonsteroidal anti-inflammatory drugs for an early analgesic effect after total knee arthroplasty and total hip arthroplasty. Patient satisfaction and benefits from the treatment were also assessed. METHODS: A total of 110 patients who were scheduled to undergo total knee arthroplasty and 86 patients who were scheduled to undergo total hip arthroplasty were divided into two groups, the study group and the control group. The study group received a periarticular multimodal drug injection during surgery. The control group received an equal volume of normal saline. All patients received an analgesia pump and a moderate dose of nonsteroidal anti-inflammatory drugs. Resting and motion Numeric Rating Scale scores, the Western Ontario and McMaster Universities Arthritis Index, knee or hip joint range of motion, length of postoperative hospital stay, patient satisfaction, total nonsteroidal anti-inflammatory drug consumption and side effects were recorded. RESULTS: Both study groups exhibited significant improvement in pain Numeric Rating Scale scores during rest and exercise several days after the surgery. The range of joint motion was greater in the study group, and the length of postoperative hospital stay was shorter than that in the control group. Patients in the study group consumed fewer nonsteroidal anti-inflammatory drugs and reported greater satisfaction with surgery. CONCLUSION: Intraoperative periarticular multimodal drug injection significantly relieved pain after surgery and reduced nonsteroidal anti-inflammatory drug consumption. These patient had a better postoperative experience, including satisfaction and rehabilitation.

Apoptosis associated with Wnt/ß-catenin pathway leads to steroid-induced avascular necrosis of femoral head.

BACKGROUND: The objective of the current study was to establish a rat model to investigate apoptosis in steroid-induced femoral head osteonecrosis occurring via the Wnt/ß-catenin pathway. METHODS: Male Sprague-Dawley (SD) rats were randomly divided into a control group (group A), model group (group B) and sFRP1 group (group C), each consisting of 24 rats, and the rats were intravenously injected with LPS (10 µg/kg body weight). After 24 h, three injections of MPS (20 mg/kg body weight) were administered intramuscularly at 24-h intervals. The rats in group C were injected intramuscularly with 1 µg/kg sFRP1 protein per day for 30 days, beginning at the time of the first MPS administration. The group A rats were fed and housed under identical conditions but received saline injection. All animals were sacrificed at weeks 2, 4 and 8 from the first MPS injection. Histopathological staining was preformed to evaluated osteonecrosis. Apoptosis was detected via quantitative terminal deoxynucleotidyl transferase (TdT) deoxyuridine triphosphate nick-end labelling (TUNEL) staining, caspase-3 activity assay, and detection of Bcl-2 and Bax protein expression by immunohistochemistry and Western blotting. Wnt/ß-catenin pathway signalling molecules, including activated ß-catenin and c-Myc, were detected by immunohistochemistry and Western blotting. RESULTS: Typical osteonecrosis was observed in groups B and C. Apoptosis gradually increased with increasing time in both groups B and C. More severe osteonecrosis and apoptosis were observed in group C compared with group B. The expression levels of caspase-3 and Bax were higher while that of Bcl-2 was lower in group C compared with group B. The expression levels of activated ß-catenin and c-Myc gradually decreased with increasing time in both groups B and C, and they were lower in group C compared with group B. CONCLUSIONS: The Wnt/ß-catenin pathway is involved in the pathogenesis of early stage SANFH, as we have demonstrated in an SANFH rat model, and it may act through the regulation of c-Myc, which affects the cell cycle and cell apoptosis.

Repair effect of coexpression of the hVEGF and hBMP genes via an adeno-associated virus vector in a rabbit model of early steroid-induced avascular necrosis of the femoral head.

We investigated the repair effect of coexpression of the human vascular endothelial growth factor (hVEGF) and human bone morphogenetic protein (hBMP) genes via an adeno-associated virus (AAV) vector in a rabbit model of early steroid-induced avascular necrosis of the femoral head (SANFH). The following AAV vectors were constructed: AAV-green fluorescent protein, AAV-VEGF, AAV-BMP, and AAV-VEGF/BMP. The rabbit model was induced using lipopolysaccharide and methylprednisolone. Virus vector was injected into the core decompression region at a dose of 25 µL per side after core decompression operation in each group. hVEGF165 and BMP-7 expressions were determined by Western blotting and immunohistochemical staining, and the femoral head was examined by magnetic resonance image scan, histopathologic staining, ink vessel staining, microcomputed tomography scan, and biomechanical assessment to determine the repair effect. The vector AAV-VEGF/BMP successfully expressed hVEGF165 and BMP-7 at the gene and protein levels at 12 weeks after virus injection. The expression of hVEGF165 promoted metabolism of the necrotic region by inducing vessel formation. The expression of BMP-7 promoted osteogenesis by increasing the mineral density and biomechanical strength of the femoral head. The repair effect of the AAV-VEGF/BMP group was better than those of the AAV-VEGF and AAV-BMP groups in the rabbit early SANFH model. The AAV-VEGF/BMP vector improved the bone repair capacity of the necrotic femoral head by inducing angiogenesis and improving bone quality in the femoral head.

Partial greater trochanter osteotomy for hip reduction in total hip arthroplasty for high dislocated hip: a preliminary report.

BACKGROUND: Hip reduction in total hip arthroplasty for high dislocated hips is difficult. Various femur osteotomy procedures have been used for hip reduction, but these methods increase operative time and risk of nonunion. We investigated the efficacy of a novel partial greater trochanter osteotomy technique for hip reduction in total hip arthroplasty for patients with high hip dislocation. METHODS: Twenty-one patients (23 hips) with high dislocated hip were treated with total hip arthroplasty that included partial greater trochanter osteotomy, i.e., the upper 2/3 greater trochanter was resected, and the gluteus medius muscle attachment was spared. The clinical outcome was evaluated by comparing the Harris hip scores and radiographic exam results, obtained before surgery and at follow-ups. RESULTS: Follow-ups of 21 patients ranged from 13 to 56 months. The mean Harris hip score increased from preoperative 55.0 (36-69) to postoperative 86.1 (71-93; P = 0.00). The average preoperative leg length discrepancy in patients with unilateral high hip dislocation was 46 mm (28-65 mm); postoperatively leg length discrepancy was less than 1 cm in 11 patients, between 1 and 2 cm in 8 patients, and more than 2 cm in 2 patients. The average leg lengthening at the time of surgery was 36 mm (24-54 mm). Trendelenburg's gait changed from positive to negative in 20 hips by the last follow-up. No nerve injury occurred postoperative. CONCLUSION: Partial greater trochanter osteotomy is an effective method to render hip reduction in total hip arthroplasty for patients with high dislocation of the hip.

[Case-control study on effects of external fixation combined with limited internal fixation for the treatment of Pilon fractures of Rüedi-Allgower type III].

OBJECTIVE: To analyze the effects of three surgical operations in the treatment of Pilon fracture of Rüedi-Allgower type III, and put forward the best therapeutic method. METHODS: The clinical data of 33 patients with Pilon fracture who received surgical operations (plaster immobilization group, 10 cases; distal tibia anatomical plate group, 11 cases; external fixation with limited internal fixation group, 12 cases) from October 2009 to January 2012 were analyzed. There were 5 males and 5 females, ranging in age from 24 to 61 years in the plaster immobilization group. There were 7 males and 4 females, ranging in age from 21 to 64 years in the distal tibia anatomical plate group. There were 7 males and 5 females, ranging in age from 23 to 67 years in the external fixation with limited internal fixation group. The Ankle X-ray of Pilon fracture after operation, ankle score, early and late complications were collected. Bourne system was used to evaluate ankle joint function. RESULTS: After 8 months to 3 years follow-up, it was found that three kinds of treatment had significant differences in the outcomes and complications (P < 0.05): the external fixation with limited internal fixation group got the best results. The number of anatomic reduction cases in the external fixation with limited internal fixation group (7 cases) and the distal tibia anatomical plate group (8 cases) was more than the plaster immobilization group (2 cases). According to the ankle score, 8 patients got an excellent result, 3 good and 1 poor in the limited internal fixation group ,which was better than those of distal tibia anatomical plate group (5 excellent, 4 good and 2 poor) and the plaster immobilization group (3 excellent, 4 good and 3 poor). The number of early and late complications in the external fixation with limited internal fixation group was more than those in the plaster immobilization group and the distal tibia anatomical plate group (P< 0.05). CONCLUSION: Treatment of external fixation with limited internal fixation in the treatment of Pilon fracture of Rüedi-Allgower type III is effective and safe.

Downregulation of microRNA-26a is associated with metastatic potential and the poor prognosis of osteosarcoma patients.

Accumulating evidence indicates that microRNAs are involved in multiple processes in cancer development and progression. microRNA-26a (miR-26a) has been identified as a tumor suppressor and its downregulation is associated with poor prognosis in several types of human cancer. However, the specific function of miR-26a in osteosarcoma remains unclear. In the present study, we found that the expression of miR-26a in osteosarcoma tissues and cell lines was much lower than that in the normal controls, respectively. In addition, downregulation of miR-26a more frequently occurred in osteosarcoma specimens with adverse clinical stage and with the presence of distant metastasis. Moreover, multivariate survival analyses demonstrated that loss of miR-26a is an independent prognostic factor for both disease-free and overall survival in osteosarcoma. In addition, restoration of miR-26a expression inhibited the invasion and migration in osteosarcoma cells, and miR-26a directly inhibited enhancer of zeste homolog 2 (EZH2) expression by targeting its 3'-UTR. Moreover, EZH2 was upregulated and inversely correlated with miR-26a expression in the osteosarcoma tissues. Thus, for the first time, we provide convincing evidence that downregulation of miR-26a is associated with tumor aggressiveness and tumor metastasis, and miR-26a inhibits cell migration and invasion by targeting the EZH2 gene in osteosarcoma. Thus, miR-26a is an independent prognostic marker for osteosarcoma patients.

[Effects of artificial disc replacement with angles on stress of adjacent intervertebral disc].

OBJECTIVE: To evaluate stress changes of intervertebral space and adjacent intervertebral space after artificial disc replacement with angles. METHODS: Artificial disc replacement with angles were designed according to existing data. Axial pressure, flexion/extension, lateral bending and torsion loading were applied on finite element models of normal cervical discs on C4,5 segments, C4,5 segments with 0 degrees artificial cervical discs and C4,5 segments with 10 degrees artificial cervical discs, then stress changes of C4,5 space was observed. The same loadings were applied on finite element models of normal cervical discs on C4-C6 segments, C4,5 segments with 0 degrees, C4,5 segments with 10 degrees, then stress changes of replaced segments space and adjacent segment space were observed. RESULTS: For C4,5 segments, 80 MPa/0 degrees artificial discs and 80 MPa/10 degrees artificial discs had the similar equivalent shear stress (Se), and were both larger than that of normal discs, when lateral bending were performed, 80 MPa/0 degrees artificial discs were closed to normal discs when axial pressure and flexion/extension were carried out, while 80 MPa/10 degrees artificial discs had a larger Se than that of normal ones,when torsion loading were applied, Szx/Szy stress of 80 MPa/0 degrees and 80 MPa/10 degrees artificial discs were closed to normal ones. For C4-C6 segments, the axial pressure, flexion/extension and lateral bending of C5,6 were all lower than normal discs after C4,5 discs were replaced by 80 MPa/10 degrees artificial discs, while Szx/Szy of torsion loading were closed to normal ones. CONCLUSION: Artificial discs with 10 degrees have less influences on stress of adjacent intervertebral space and closer to mechanical property after being implanted into intervertebral space.

Effects of sodium ferulate on preventing steroid-induced femoral head osteonecrosis in rabbits.

The aim of this study is to investigate the effects and possible mechanisms of sodium ferulate (SF) on anti-apoptosis in steroid-induced femoral head osteonecrosis in rabbits. Japanese white rabbits were randomly divided into three groups (control group, treatment group, and model group), each with 24 rabbits. The model and treatment groups were first injected with an intravenous dose of horse serum, 10 ml/kg, three weeks later with an intravenous dose of 7.5 ml/kg, and two weeks later with an intramuscular dose of methylprednisolone, 45 mg/kg, three times in order to establish rabbit models of osteonecrosis. Concurrently, the treatment group was injected with intravenous doses of SF 20 mg/kg for two weeks, once per day. Three time points, Weeks 2, 4, and 8, were selected after modeling was completed. Osteonecrosis was verified by histopathology with haematoxylin-eosin (HE) staining. The apoptosis rate of osteonecrosis was observed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The apoptosis expressions of caspase-3 and Bcl-2 were analyzed by immunohistochemistry and Western blot. The rabbit models of osteonecrosis were successfully established and observed by HE staining. SF was effective in intervening in apoptosis and decreasing the apoptosis rate in femoral head necrosis by the immunohistochemistry and TUNEL assay (P<0.01). Western blot analysis indicated that there were statistical significances in the protein levels of caspase-3 and Bcl-2 (P<0.01). SF has a protective effect by reducing the incidence of early steroid-induced femoral head necrosis in rabbits, effectively intervening in apoptosis through decreasing caspase-3 expression and up-regulating Bcl-2 expression.

[Analysis of chronergy for treatment of spinal cord injury with the allogeneic bone mesenchymal stem cells (BMscs) transplantation in rats].

OBJECTIVE: To observe the change of behavior, pathological change of the spinal cord,and expression of brain-derived neurotrophic factor (BDNF) and brain-derived neurotrophic factor (NGF) on rats with spinal cord injury in order to explore the optimal time of BMSCs transplantation. METHODS: Eighty health SD rats were randomly divided into 8 groups (group A,B,C,D,E,F,G,H), 10 rats in each group. According to the modified Allen method,the rat model of spinal cord injury was built. Group A as non-injured group only exposed the spinal cord but not result in blast injury. BMSCs of vitro culture were respectively infunded the region of spinal cord injury in group C, D, E, F, G, H (as transplantation groups) at the 0 h, 6 h, 24 h,3 d,5 d,7 d after model made. Group B as single model group was infunded the equal cell culture fluid. BBB score was used to evaluate the function of spinal cord at the 1st,2nd and 4th weeks after injury. The morphological changes of the tissue of spinal cord injury were observed by HE stain and the expression of BDNF and NGF were detected by Elisa method at the 4th weeks after BMSCs transplantation. RESULTS: In non-injured group,BBB score was highest than that of other 7 groups at the 1st, 2nd and 4th weeks after injury (P<0.01). There was no significant difference in BBB score between single model group and transplantation groups at the 1st week after BMSCs transplantation (P>0.05). BBB score in transplantation groups were higher than that of single model group at the 2nd and 4th weeks after BMSCs transplantation (P<0.05). At the 2nd week after injury, BBB score from high to low was group F,E,G,D,H,C,but there was no significant difference among the groups (P>0.05). At the 4th week after injury,there was significant differences in BBB score between group F and other transplantation groups (group C,D,E,G,H)(P0.05). The levels of BDNF and NGF in group F was highest at the 4th week after BMSCs transplantation (P<0.05). In non-injured group,HE staining showed the struction of spinal cord was clear and complete,no neutrophil was found. But in other 7 groups,HE staining showed obviously oedema at local tissue,juncture of gray and white matter was undefined,and different gliocyte proliferation and inflammatory cell infiltrate cound be found. CONCLUSION: Allogeneic BMSCs transplantation is effective to stimulate the recovery of spinal cord function in rats with spinal cord injury,and the optimal time of BMSCs transplantation maybe at the 3 d after injury.

The cyclooxygenase-2 inhibitor NS-398 inhibits proliferation and induces apoptosis in human osteosarcoma cells via downregulation of the survivin pathway.

Cyclooxygenase-2 (COX-2) is frequently overexpressed in human malignancies and plays a crucial role in tumorigenesis and cancer progression. The present study aimed to investigate the expression and clinical significance of COX-2 and survivin (SUV) in human osteosarcomas (OS), and explore the effects and molecular mechanisms of a selective COX-2 inhibitor NS-398 and SUV on tumor proliferation and apoptosis. Fifty cases of human OS and osteochondromas (OC) were collected. The expression of COX-2 and SUV was assessed using immunohistochemical assays in biopsy samples. MG-63 human OS cells were treated with different concentrations of NS-398, used to investigate their effects on cell proliferation and apoptosis. The recombinant small hairpin RNA adenovirus vector rAd5-SUV was constructed, and the effects and molecular mechanisms of knockdown of SUV on proliferation and apoptosis were evaluated in MG-63 cells. A subcutaneous xenograft tumor model was established, validating the effects of rAd5-SUV on tumor growth in vivo. Based on the results, the expression of COX-2 and SUV in OS showed a higher strong reactivity rate compared with OC (73.3 vs. 25.0%, P=0.001; 63.3 vs. 30.0%, P=0.02), but it did not correlate with the clinicopathological characteristics of OS. NS-398 inhibited proliferation, induced apoptosis and decreased the mRNA expression of COX-2 and SUV in MG-63 cells. Furthermore, adenovirus-mediated knockdown of SUV inhibited proliferation, induced apoptosis, reduced the expression of proliferating cell nuclear antigen (PCNA), increased the expression of caspase-3 (CAS-3) and slowed the growth of xenograft tumors in MG-63 cells. Taken together, the expression of COX-2 and SUV is closely correlated with human OS, and inhibition of COX-2 or knockdown of SUV suppresses tumor proliferation and induces apoptosis, suggesting that COX-2 may be involved in OS cell proliferation and apoptosis through SUV-mediated regulation of PCNA and CAS-3 expression, and provides a potential therapeutic strategy for the treatment of cancer.

In vitro and in vivo effects of puerarin on promotion of osteoblast bone formation.

OBJECTIVE: To assess the effect of puerarin, a natural flavonoid found in Chinese Pueraria Lobata (Wild.) Ohwi, on promotion of new bone formation. METHODS: Osteoblasts isolated from calvarial of newborn rats were cultured in vitro in the presence of puerarin at various concentrations. The viability of osteoblasts and alkaline phosphotase activity and mineral node formation were determined. In addition, osteoblasts seeded in the ß-tricaclium phosphate scalfolds as bone substitute were implanted in rat dorsal muscles. Half -of the recipient rats received intramuscular injection of puerarin at 10 mg/(kg·d) for 7 days. Osteogenesis was analyzed by examining the histology after 4 weeks of implantation. RESULTS: The viability of osteoblasts treated with puerarin at either 40 or 80 µmol/L was significantly higher than that of the control (P<0.05 and P<0.01, respectively). Alkaline phosphatase and mineral modules were significantly increased in osteoblasts cultured with puerarin at 40 or 80 mol/L when compared with that of the untreated cells. The puerarin-treated rats had a higher rate of bone formation in the osteoblast implants than the control rats (6.35% vs. 1.32%, respectively, P<0.05). CONCLUSION: Puerarin was able to affect osteoblast proliferation and differentiation, and promote the new bone formation in osteoblast implants.