CYLD alleviates NLRP3 inflammasome-mediated pyroptosis in osteoporosis by deubiquitinating WNK1.

BACKGROUND: Osteoporosis (OP) is the result of bone mass reduction and bone structure disorder. Bone marrow mesenchymal stem cells (BMSCs) are the main source of osteogenic precursor cells involved in adult bone remodeling. The involvement of the deubiquitinating enzyme CYLD in OP has recently been discovered. However, the detailed role and mechanism of CYLD remain unknown. METHODS: The OP mouse model was established by performing ovariectomy (OVX) on mice. Hematoxylin and eosin staining, Masson and Immunohistochemical staining were used to assess pathologic changes. Real-time quantitative PCR, Western blot, and immunofluorescence were employed to assess the expression levels of CYLD, WNK1, NLRP3 and osteogenesis-related molecules. The binding relationship between CYLD and WNK1 was validated through a co-immunoprecipitation assay. The osteogenic capacity of BMSCs was determined using Alkaline phosphatase (ALP) and alizarin red staining (ARS). Protein ubiquitination was evaluated by a ubiquitination assay. RESULTS: The levels of both CYLD and WNK1 were decreased in bone tissues and BMSCs of OVX mice. Overexpression of CYLD or WNK1 induced osteogenic differentiation in BMSCs. Additionally, NLRP3 inflammation was activated in OVX mice, but its activation was attenuated upon overexpression of CYLD or WNK1. CYLD was observed to reduce the ubiquitination of WNK1, thereby enhancing its protein stability and leading to the inactivation of NLRP3 inflammation. However, the protective effects of CYLD on osteogenic differentiation and NLRP3 inflammation inactivation were diminished upon silencing of WNK1. CONCLUSION: CYLD mitigates NLRP3 inflammasome-triggered pyroptosis in osteoporosis through its deubiquitination of WNK1.

Limb Reconstruction System Assisted Reduction and Internal Fixation for Intra-Articular Calcaneal Fractures: A New Application.

BACKGROUND: Minimally invasive reduction and fixation of intra-articular calcaneal fractures poses great challenges for orthopaedic surgeons. The aim of the present study was to report the technical points, evaluate the efficacy of minimally invasive reduction and internal fixation assisted by the temporary limb reconstruction system (LRS) external fixator for intra-articular calcaneal fractures, and propose the indications of our protocol. METHODS: In this retrospective study, a series of 34 consecutive closed and displaced intra-articular calcaneal fractures involving the articular surface were treated by this technology between June 2016 and April 2018. X-ray and computed tomography (CT) scans were performed before and after surgery to measure Bohler's angle; the length, height, and width of the calcaneus; and the mechanical axis of the hindfoot. Postoperative complications were recorded. Imaging and clinical outcomes were comprehensively evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle scoring system. After testing the normality of the data, Bohler's angle and the length of calcaneus were compared using the Wilcoxon signed-rank test. The height, width of the calcaneus, and the mechanical axis of the hindfoot were compared using the Paired-Samples t-test. RESULTS: Thirty-two fractures were followed up for an average of 20.66 months (from 12 to 32 months). All fractures achieved stable reduction and bony union. The articular surface was reduced and fixed with direct vision through the sinus tarsi incision. No failure of internal fixation or loss of reduction was detected during follow-up. There were no soft tissue complications. Bohler's angle; the length, height, and width of the calcaneus; and the mechanical axis of the hindfoot improved significantly. The AOFAS scores averaged 84.12 points; seven cases were rated excellent, 20 good, four fair, and one poor. CONCLUSIONS: For intra-articular calcaneal fractures, minimally invasive surgery assisted with temporary LRS external fixation can reconstruct the calcaneal shape and the sub-talar articular surface. This simple surgical modality with limited complications may be helpful in the surgical treatment of most type II and III calcaneal fractures except comminuted fractures of the calcaneal tuberosity.

Multiple Reconstructive Osteotomy Treating Malunited Calcaneal Fractures Without Subtalar Joint Fusion.

OBJECTIVE: Various surgical techniques have been reported in treating calcaneal malunions over the decades, while the operations on single plane were accompanied by respective limitations. The purpose of this study is to evaluate the efficacy of a novel multiple reconstructive osteotomy for treating malunited calcaneal fractures without subtalar joint fusion. METHODS: From March 12, 2010, to August 17, 2017, 10 patients (10 feet) with malunited calcaneal fractures were treated with multiple reconstructive osteotomy with subtalar joint-preserving operations. All patients were treated with a corrective osteotomy, joint realignment, soft tissue balancing, and secondary internal fixation at a mean of 5.6 ± 2.41 months since the initial injury. With the utilization of the multiple reconstructive osteotomy, the posterior facet was restored to preserve the subtalar joint. All patients were evaluated clinically and radiographically at a mean follow-up of 3.04 ± 1.21 years. RESULTS: All patients were subjectively satisfied with the treatment. The average time to union was 12.2 ± 1.11 weeks. The American Orthopedic Foot and Ankle (AOFAS) ankle and hind foot score was 86.3 ± 4.45 (t = 27.64, P < 0.0001, paired t-test), which was significantly higher than the preoperative assessment. Postoperative radiographic assessment revealed great improvement in Böhler's angle (from 25.4° to 86.3°), talocalcaneal height (65.15-72.68 mm) and Calcaneus-talus angle (from 34.46° to 39.7°). One patient had mild discomfort after a 1-h brisk walk. One patient was suspected to have early posttraumatic arthritis of the subtalar joint based upon radiographic evidence during the follow-up, but the patients could walk normally for a long time without pain. CONCLUSION: Multiple reconstructive osteotomy is an effective way to restore the calcaneal morphology and preserve the subtalar joint for selected calcaneal malunion.

Malunited calcaneal fracture: the role and technique of osteotomy-a systematic review.

PURPOSE: The research is aimed to introduce various corrective osteotomies utilized in treating calcaneal malunions in published papers, to further analyze the results, and to summarize recommended indications. METHODS: The relevant research screening was conducted on the following search engines: the Cochrane Library, Web of Science, PubMed, Embase, Medline, and Academic Search Premier. Key words input included "calcaneal/calcaneus", "malunion," and "malunited fracture(s)" with Boolean operators "AND" and "OR." The inclusion criteria were researches containing surgical procedures treating calcaneal malunion with corrective osteotomy and published in the English language. For included research article, such information was extracted and analyzed: the type of calcaneal malunion, the time from initial injury to corrective surgery, the method of osteotomy, outcomes of each osteotomy (score systems, Bohler angle, talocalcaneal height and width of calcaneus, etc.), the function of the affected limb, post-operative complications, and patients' satisfaction. For included review, descriptive, commentary, or indicative sentences about corrective osteotomy were highlighted, analyzed, and summarized. RESULTS: Ten research articles (170 patients with 184 feet) and nine reviews were included in this review, presenting seven types of corrective osteotomies (lateral wall exostectomy, Dwyer osteotomy, lateral wedge opening osteotomy, Romash osteotomy, tongue osteotomy, sagittal resection osteotomy, and modified Dwyer osteotomy). CONCLUSION: A different corrective osteotomy with/without arthrodesis is recommended to be utilized based on the classification of the malunion and the condition of the cartilage in treating malunited calcaneal fractures. With adequate postoperative care and rehabilitation, the results of treatment could be associated with patients' satisfaction and good function.

Surgical treatment for patients with hemophilic pseudotumor-related femoral fracture: a retrospective study.

BACKGROUND: Hemophilic pseudotumor (HPT)-related fracture is a rare but severe complication in patients with HPTs. These fractures often occur in femurs. There is no consensus on the standard surgical protocol for HPT-related femoral fracture. The present retrospective study evaluated the outcomes of these patients treated with surgical interventions. METHODS: Ten patients with HPT-related femoral fractures who were treated with 14 surgical procedures due to 11 fractures in our hospital from January 2014 to April 2020 were evaluated retrospectively. Demographic data, fracture location, complications after surgery, and follow-up outcomes were recorded and analyzed. The mean follow-up period was 39.7 months. RESULTS: The mean age at surgery was 31 years. Closed reduction external fixation (CREF) was originally performed in 2 patients, open reduction internal fixation (ORIF) was performed in 4 patients, screw fixation alone was performed in 1 patient, brace immobilization was performed in 1 patient, and amputation was performed in 3 patients. Bone union was observed in 5 patients, and an adequate callus was visible in 2 patients. Both patients with CREF had pin infections. Nonunion combined with external fixation (EF) failure occurred in 1 patient, and the plate was broken after ORIF. Three patients underwent autogenous or allogeneic cortical strut grafting. Three patients had HPT recurrence. CONCLUSIONS: It is necessary to perform surgery in patients with HPT-related femoral fractures. Surgical treatments must consider fracture stabilization and HPT resection. Internal fixation is preferable, and EF should only be used for temporary fixation. If the HPT erodes more than one third of the bone diameter, strut grafts are necessary for mechanical stability. Amputation is an appropriate curative method in certain situations.

Value of Golgi protein 73 monoclonal antibody in diagnosis of hepatocellular carcinoma / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the sensitivity and specificity of Golgi protein 73 (GP73) monoclonal antibody in the diagnosis of hepatocellular carcinoma (HCC).</p><p><b>METHODS</b>Self-prepared GP73 monoclonal antibody was used as the primary antibody for detecting the serum GP73 levels in healthy controls(n=31)and HCC patients (n=59). The baseline level of the healthy controls was determined by semiquantitative analysis. The results were compared with those from GP73 polyclonal antibody and alpha-fetoprotein (AFP).</p><p><b>RESULTS</b>The GP73 level of healthy controls was 1.2 (0.9-1.7) relative unit (RU), which was significantly lower than that of HCC patients [5.7 (2.5-7.8) RU] (P<0.001) with monoclonal antibody. Using polyclonal antibody, the GP73 level of HCC patients was also significantly higher than healthy controls [7.8 (3.0-12.4) RU vs. 1.1 (1.0-2.0) RU, P<0.001]. The sensitivity and specificity of GP73 monoclonal antibody in diagnosis of HCC were 84.7% and 93.5%; on the contrary, those of GP73 polyclonal antibody were 78.0% and 93.5%, respectively. The sensitivity and specificity of AFP (67.8% and 74.2%, respectively) in the HCC patients were markedly lower than those of GP73. Logistic regression analysis showed that the odds ratio (OR) of GP73 monoclonal antibody was 7.18 and that of GP73 polyclonal antibody was 1.51.</p><p><b>CONCLUSIONS</b>Our self-prepared monoclonal antibody can effectively detect GP73 serum level in HCC patients, and has higher sensitivity and specificity than AFP. It may be superior to the currently used GP73 polyclonal antibody. The results lay the foundation for the further development of ELISA methods by using this monoclonal antibody.</p>