Exploring molecular mechanisms of intra-articular changes in osteonecrosis of femoral head using DIA proteomics and bioinformatics.

PURPOSE: This study is aimed to delve into the crucial proteins associated with hormonal osteonecrosis of the femoral head (ONFH) and its intra-articular lesions through data-independent acquisition (DIA) proteomics and bioinformatics analysis. METHODS: We randomly selected samples from eligible ONFH patients and collected samples from the necrotic area of the femoral head and load-bearing cartilage. The control group comprised specimens from the same location in patients with femoral neck fractures. With DIA proteomics, we quantitatively and qualitatively tested both groups and analyzed the differentially expressed proteins (DEPs) between groups. Additionally, we enriched the analysis of DEP functions using gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways and verified the key proteins in ONFH through Western blot. RESULTS: Proteomics experiment uncovered 937 common DEPs (422 upregulated and 515 downregulated) between the two groups. These DEPs mainly participate in biological processes such as hidden attributes, catalytic activity, molecular function regulators, and structural molecule activity, and in pathways such as starch and sucrose metabolism, ECM-receptor interaction, PI3K-Akt signaling, complement and coagulation cascades, IL-17 signaling, phagosome, transcriptional misregulation in cancers, and focal adhesion. Through protein-protein interaction network target gene analysis and Western blot validation, we identified C3, MMP9, APOE, MPO, LCN2, ELANE, HPX, LTF, and THBS1 as key proteins in ONFH. CONCLUSIONS: With DIA proteomics and bioinformatics analysis, this study reveals the molecular mechanisms of intra-articular lesions in ONFH. A correlation in the necrotic area and load-bearing cartilage of ONFH at ARCO stages IIIB-IV as well as potential key regulatory proteins was identified. These findings will help more deeply understand the pathogenesis of ONFH and may provide important clues for seeking more effective treatment strategies.

Effect of N-cadherin on Chondrogenic Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells through Wnt Signaling Pathway.

This study aimed to compare and analyze the effect of N-cadherin on chondrogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) and to explore the related mechanism, so as to provide a novel theoretical basis for the clinical work of articular cartilage injury regeneration and repair. For this purpose, the experimental animals were clean grade SD rats (aged 5-6 weeks, weighing 180-250g). Alcian blue staining was carried out to observe the induced chondrogenesis following N-cadherin inhibition. The specific role of N-cadherin in the Wnt signaling pathway and chondrogenic differentiation of BMSCs was detected by Western blot; while the effect of N-cadherin on the molecular level changes of ß-catenin in the cytoplasm was evaluated by fluorescence quantitative real-time PCR (qRT-PCR). In addition, immunoprecipitation (IP) was used for the verification of the interaction between N-cadherin and ß-catenin. Results showed that under the light microscope, 90% of the BMSCs at the third generation, 90% of the cells were fused. Alcian blue staining showed that the green staining area in the BMP2 induction group was large and dense, while that in the N-cadherin inhibition group and blank control group was small and sparse. Western blot revealed that N-cadherin and SOX9 were significantly developed in the BMP2 induction group, but Wnt3a was not significantly developed. While in the N-cadherin inhibition group, the development of Wnt3a was obvious, yet without evident development of N-cadherin and SOX9. The qRT-PCR indicated that the relative mRNA expression of Wnt3a was significantly increased in the N-cadherin inhibition group (P<0.05). However, no obvious difference was observed in the mRNA expression of ß-catenin between the BMP2 induction group and the N-cadherin inhibition group (P>0.05). Western blot indicated that in the BMP2 induction group; there existed the development of ß-catenin, significant development of phos-GSK-3ß and total GSK-3ß, but no obvious development of Wnt3a. In the N-cadherin inhibition group, there was significantly enhanced development of Wnt3a and ß-catenin than that before, blurred development of phos-GSK-3ß than that before, and also obvious development of total GSK-3ß with little change from before. N-cadherin promoted the expression of ß-catenin mostly in the cell membrane, but only a few in the cytoplasm and nucleus. Additionally, verification by IP showed that N-cadherin and ß-catenin were developed on N-cadherin and ß-catenin bands, suggesting an interaction between N-cadherin and ß-catenin. According to these results, N-cadherin can ultimately promote chondrogenic differentiation of BMSCs by inhibiting the Wnt signaling pathway.

Risk factors of young males with physically demanding occupations having accumulated damage of anterior cruciate ligament.

OBJECTIVE: To present the clinical characteristics of accumulated anterior cruciate ligament (ACL) damage among young male patients undergoing routine exercise, and to evaluate the related risk factors. METHODS: A retrospective study involving ACL-accumulated damage from June 2015 to December 2019 was conducted. Baseline characteristics, such as age, body mass index (BMI), training parameters, and clinical signs, were recorded. The results of the radiologic examinations and related standardized tests were obtained to evaluate the research outcomes. These results were compared using Student's t-test or Chi-square test, and the impact of risk factors on the patient's injury were analyzed. RESULTS: A total of 86 men with accumulated ACL damage were included in this study. Exercise pain (86 [100%]), synovitis (80 [93.0%]), and intra-articular effusion (79 [91.9%]) were the most common clinical symptoms. Loosening of ligaments, decreased tension, mild hyperplasia, and intercondylar fossa effusion were observed using radiography, magnetic resonance imaging, and arthroscopy. Age, BMI, training intensity, length of training, and knee hyperextension were identified as risk factors for accumulated ACL damage. CONCLUSION: This study suggests that accumulated ACL damage has differentiated clinical symptoms, imaging features, and risk factors compared to common ACL injuries.

Arthroscopic treatment for patients with borderline developmental dysplasia of the hip and cam-type femoroacetabular impingement syndrome / 中华骨科杂志

Objective:To evaluate the clinical outcomes of patients with borderline developmental dysplasia of the hip (BDDH) and cam-type femoroacetabular impingement syndrome (FAIS) after hip arthroscopy.Methods:Data were retrospectively reviewed for patients with BDDH and cam-type FAIS who underwent hip arthroscopy surgery from June 2017 to December 2019. A total of 32 patients were enrolled, with a mean age of 36.13±8.67 years (range, 20-50 years), including 15 males and 17 females. The preoperative lateral center-edge angle was 22.3°±1.6° (range 20.1°-24.7°), while the preoperative α angle was 64.1°±4.6° (range, 56.0°-69.8°). All patients were treated with arthroscopic limited acetabular plasty, labral repair, femoral osteoplasty, and capsular plication after excluding from external hip diseases by ultrasound-guided hip blocking test. The visual analogue scale (VAS), modified Harris Hip Scores (mHHS) and International Hip Outcome Tool-12 (iHOT-12) scores were used to evaluate the clinical effects.Results:All patients were followed up, and the mean follow-up time was 2.5±0.8 years (range, 2.0-4.7 years). The VAS score decreased from 6.07±1.56 to 1.96±0.92 at 1 year and to 1.86±1.01 at 2 years after operation ( F=112.64, P<0.001); the mHHS score increased from 53.87±13.04 to 86.12±8.64 at 1 year and to 88.71±8.15 at 2 years after operation ( F=101.70, P<0.001); the iHOT-12 score was improved from 40.00±7.33 to 76.27±9.50 at 1 year and to 78.67±10.31 at 2 years after operation ( F=134.91, P<0.001). The α angle improved to 40.27°±4.52° (range, 34.8°-49.7°) with significant difference ( t=9.24, P<0.001). Conclusion:Hip arthroscopy can achieve satisfied short-term outcomes in treating BDDH and cam-type FAIS with few complications and less trauma.

Portal Setup: the Key Point in the Learning Curve for Hip Arthroscopy Technique.

OBJECTIVE: To analyze the learning curve experience of hip arthroscopy based on patient demographics, surgical time, portal setup time, and postoperative complications and to find the key point in the learning curve. METHODS: From May 2016 to February 2019, a prospective study on the learning curve experience of hip arthroscopy was performed in our hospital. We evaluated the first 50 consecutive hip arthroscopy procedures performed by a single surgeon. There were nine females and 41 males with a mean age of 30.8 years. We divide the patients into early group and late group according to the date of their operation, with each group including 25 patients. Data on patient demographics, types of procedure, surgical time, portal setup time, and postoperative complications were collected. Functional scores were assessed with the modified Harris Hip Score (mHHS). RESULTS: Patients were followed up for 16.4 months on average (range, 13-27 months). The early group of patients had a mean age of 35.2 years and the late group a mean age of 26.5 years. The most common procedures performed for the early group were debridement (17 patients, 68%), and in the late group, most patients underwent labral repair (18 patients, 72%). Mean total surgical time was 168 min for the early group and 143 min for the late group, and there was no statistically significant difference between two groups. The portal setup time in the early group and late group was 40.2 ± 12.4 min and 18.5 ± 6.2 min, respectively (P < 0.001), and the portal setup time was significantly longer in the early group. Further analysis of the learning curve of portal setup showed that the average portal setup time was not statistically significant changed after 30 cases. There were six complications including iatrogenic cartilage injury and iatrogenic labrum injury in the early group and five complications including perineal crush injury and nerve stretch injury in the late group. The functional score of patients in the late group was significantly higher than that in the early group during follow-up. CONCLUSION: The steep learning curve of hip arthroscopy is mainly caused by the challenge of portal setup and portalrelated complications were more common in the early group than in the late group. Surgical time is not an effective indicator for evaluating progress on the learning curve of hip arthroscopy.

Cyst of the hip ligamentum teres: a case report and literature review / 中华骨科杂志

According to the literature review, no cyst of the hip ligamentum teres has been reported. In this study, a 50?year?old female patient was admitted to the hospital because of sprained left hip pain with movement restriction for 15 months. The unilateral hip joint MRI showed cyst of the hip ligamentum teres, which was diagnosed as left hip joint cyst in the outpatient de?partment. Thus, the patient was admitted to the hospital. Physical examination showed that the left hip joint movement was slightly restricted with positive FADDIR test and FABER test. Arthroscopic surgical examination revealed a 1.5 cm×1.0 cm cyst at the lo?cation of the round ligament which was then cleared with a planer knife and radiofrequency. The treatment results were satisfacto?ry. The present study reviewed the literature about anatomical and biomechanical physicochemical properties of the ligamentum teres. The function of the ligamentum teres is important for the hip joint. In diagnosis of hip disease, unilateral hip MRI plays an important role in accurate diagnosis of such diseases. The hip arthroscopy provide a minimal invasive technique in treating cyst of the hip ligamentum teres. With the application of the hip arthroscopy, it will undoubtedly improve the diagnosis and treatment of hip diseases.

Potent growth-inhibitory effect of TRAIL therapy mediated by double-regulated oncolytic adenovirus on osteosarcoma.

Osteosarcoma (OS) severely threatens the health of young people and understanding on the molecular mechanisms of OS etiology enables gene therapy to become an effective therapeutic modality. However, insufficient expression level of genes using existing vectors limits the clinical application of gene therapy for OS. To solve the problem, we developed an oncolytic adenoviral vector, OAT, which can selectively and efficiently replicate in OS cells to enhance the expression of transferred genes. We demonstrated that OAT-mediated TRAIL expression is significantly elevated after infection of OS cells than replication-incompetent Ad5 vector. Increased antitumor capacity was observed in OS cells after OAT-TRAIL treatment both in vitro and in vivo. In normal cells, adenoviral replication, TRAIL expression and growth-inhibiting effect were quite limited when OAT-TRAIL was administrated, showing a high biosafety of this oncolytic adenoviral vector. Collectively, we generated an efficient and promising expression vector for OS gene therapy.