Unraveling Key m6A Modification Regulators Signatures in Postmenopausal Osteoporosis through Bioinformatics and Experimental Verification.

OBJECTIVE: Bone marrow mesenchymal stem cells (BMSCs) show significant potential for osteogenic differentiation. However, the underlying mechanisms of osteogenic capability in osteoporosis-derived BMSCs (OP-BMSCs) remain unclear. This study aims to explore the impact of YTHDF3 (YTH N6-methyladenosine RNA binding protein 3) on the osteogenic traits of OP-BMSCs and identify potential therapeutic targets to boost their bone formation ability. METHODS: We examined microarray datasets (GSE35956 and GSE35958) from the Gene Expression Omnibus (GEO) to identify potential m6A regulators in osteoporosis (OP). Employing differential, protein interaction, and machine learning analyses, we pinpointed critical hub genes linked to OP. We further probed the relationship between these genes and OP using single-cell analysis, immune infiltration assessment, and Mendelian randomization. Our in vivo and in vitro experiments validated the expression and functionality of the key hub gene. RESULTS: Differential analysis revealed seven key hub genes related to OP, with YTHDF3 as a central player, supported by protein interaction analysis and machine learning methodologies. Subsequent single-cell, immune infiltration, and Mendelian randomization studies consistently validated YTHDF3's significant link to osteoporosis. YTHDF3 levels are significantly reduced in femoral head tissue from postmenopausal osteoporosis (PMOP) patients and femoral bone tissue from PMOP mice. Additionally, silencing YTHDF3 in OP-BMSCs substantially impedes their proliferation and differentiation. CONCLUSION: YTHDF3 may be implicated in the pathogenesis of OP by regulating the proliferation and osteogenic differentiation of OP-BMSCs.

METTL3-mediated m6A modification of SOX4 regulates osteoblast proliferation and differentiation via YTHDF3 recognition.

N6-methyladenosine (m6A), the most prevalent internal modification in mRNA, is related to the pathogenesis of osteoporosis (OP). Although methyltransferase Like-3 (METTL3), an m6A transferase, has been shown to mitigate OP progression, the mechanisms of METTL3-mediated m6A modification in osteoblast function remain unclear. Here, fluid shear stress (FSS) induced osteoblast proliferation and differentiation, resulting in elevated levels of METTL3 expression and m6A modification. Through Methylated RNA Immunoprecipitation Sequencing (MeRIP-seq) and Transcriptomic RNA Sequencing (RNA-seq), SRY (Sex Determining Region Y)-box 4 (SOX4) was screened as a target of METTL3, whose m6A-modified coding sequence (CDS) regions exhibited binding affinity towards METTL3. Further functional experiments demonstrated that knockdown of METTL3 and SOX4 hampered osteogenesis, and METTL3 knockdown compromised SOX4 mRNA stability. Via RNA immunoprecipitation (RIP) assays, we further confirmed the direct interaction between METTL3 and SOX4. YTH N6-Methyladenosine RNA Binding Protein 3 (YTHDF3) was identified as the m6A reader responsible for modulating SOX4 mRNA and protein levels by affecting its degradation. Furthermore, in vivo experiments demonstrated that bone loss in an ovariectomized (OVX) mouse model was reversed through the overexpression of SOX4 mediated by adeno-associated virus serotype 2 (AAV2). In conclusion, our research demonstrates that METTL3-mediated m6A modification of SOX4 plays a crucial role in regulating osteoblast proliferation and differentiation through its recognition by YTHDF3. Our research confirms METTL3-m6A-SOX4-YTHDF3 as an essential axis and potential mechanism in OP.

[Study on the diagnostic value of different posterior cruciate ligament index measurement methods for anterior cruciate ligament injury].

OBJECTIVE: To compare the posterior cruciate ligament(PCL) index with six different measurement methods, and analyze and verify its clinical diagnostic value in anterior cruciate ligament (ACL) injury. METHODS: The Magnetic resonance imaging (MRI) data of 225 knee joints in our hospital from May 2018 to March 2022 were retrospectively analyzed, aged from 18 to 60 years old, with a median of 32 years old. On the sagittal MRI images of 114 patients with ACL injury and 111 patients with intact ACL, Measure the straight-line distance (A) between the femoral attachment point and the tibial attachment point of the PCL on the MRI sagittal image and the maximum vertical distance (B) between the straight line and the arcuate mark point of the PCL on the sagittal image, calculate the PCL index and evaluate the diagnostic value of the PCL index for ACL injury. RESULTS: The PCL index of the ACL normal group and the ACL injury group were statistically described. There was no significant difference in PCL index 1, 2, 3 and 6 between the two groups(P>0.05). The difference of PCL index 4 and 5 between the two groups was statistically significant (P<0.001). This study only found that the PCL index 2, 6 in the ACL normal group had a negative correlation with the patient's age (correlation coefficient=-0.213, -0.819;P<0.05), and the PCL index 5 in the ACL injury group was significantly correlated with the patient's body mass index(BMI)had a negative correlation (correlation coefficient=-0.277, P<0.05). CONCLUSION: The change of PCL index is helpful for the diagnosis of ACL injury, PCL index 4 and 5 can be used as effective reference indexes for diagnosing ACL injury in clinic.

Screening and identification of potential hub genes and immune cell infiltration in the synovial tissue of rheumatoid arthritis by bioinformatic approach.

Background: Rheumatoid arthritis (RA) is an autoimmune disease that affects individuals of all ages. The basic pathological manifestations are synovial inflammation, pannus formation, and erosion of articular cartilage, bone destruction will eventually lead to joint deformities and loss of function. However, the specific molecular mechanisms of synovitis tissue in RA are still unclear. Therefore, this study aimed to screen and explore the potential hub genes and immune cell infiltration in RA. Methods: Three microarray datasets (GSE12021, GSE55457, and GSE55235), from the Gene Expression Omnibus (GEO) database, have been analyzed to explore the potential hub genes and immune cell infiltration in RA. First, the LIMMA package was used to screen the differentially expression genes (DEGs) after removing the batch effect. Then the clusterProfiler package was used to perform functional enrichment analyses. Second, through weighted coexpression network analysis (WGCNA), the key module was identified in the coexpression network of the gene set. Third, the protein-protein interaction (PPI) network was constructed through STRING website and the module analysis was performed using Cytoscape software. Fourth, the CIBERSORT and ssGSEA algorithm were used to analyze the immune status of RA and healthy synovial tissue, and the associations between immune cell infiltration and RA-related diagnostic biomarkers were evaluated. Fifth, we used the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to validate the expression levels of the hub genes, and ROC curve analysis of hub genes for discriminating between RA and healthy tissue. Finally, the gene-drug interaction network was constructed using DrugCentral database, and identification of drug molecules based on hub genes using the Drug Signature Database (DSigDB) by Enrichr. Results: A total of 679 DEGs were identified, containing 270 downregulated genes and 409 upregulated genes. DEGs were primarily enriched in immune response and chemokine signaling pathways, according to functional enrichment analysis of DEGs. WGCNA explored the co-expression network of the gene set and identified key modules, the blue module was selected as the key module associated with RA. Seven hub genes are identified when PPI network and WGCNA core modules are intersected. Immune infiltration analysis using CIBERSORT and ssGSEA algorithms revealed that multiple types of immune infiltration were found to be upregulated in RA tissue compared to normal tissue. Furthermore, the levels of 7 hub genes were closely related to the relative proportions of multiple immune cells in RA. The results of the qRT-PCR demonstrated that the relative expression levels of 6 hub genes (CD27, LCK, CD2, GZMB, IL7R, and IL2RG) were up-regulated in RA synovial tissue, compared with normal tissue. Simultaneously, ROC curves indicated that the above 6 hub genes had strong biomarker potential for RA (AUC >0.8). Conclusions: Through bioinformatics analysis and qRT-PCR experiment, our study ultimately discovered 6 hub genes (CD27, LCK, CD2, GZMB, IL7R, and IL2RG) that closely related to RA. These findings may provide valuable direction for future RA clinical diagnosis, treatment, and associated research.

[Comparative study on posterior cruciate ligament reconstruction with autologous hamstring tendon and LARS artificial ligament in the treatment of KD-â ¢-M knee dislocation].

OBJECTIVE: To observe the curative effect of one-stage reconstruction of anterior cruciate ligament(ACL), posterior cruciate ligament (PCL) and medial collateral ligament (MCL) in patients with KD-Ⅲ-M knee injury, and to compare the operation time, hospitalization cost and curative effect after arthroscopic reconstruction of PCL with LARS artificial ligament and autogenous hamstring tendon, ACL reconstruction with autogenous hamstring tendon and MCL repair combined with limited incision. METHODS: From March 2016 to January 2019, a total of 36 patients met the criteria of this study. Twenty patients in group A were treated with autogenous hamstring tendon reconstruction of ACL and PCL and repair of MCL, including 17 males and 3 females, with an average age of (34.7±9.2) years old. Sixteen patients in group B with LARS artificial ligament reconstruction of PCL, with an autogenous hamstring tendon reconstruction of PCL and MCL repair as before as group B, including 15 males and 1 female, with an average age of (36.8±8.6) years old. The operation time, hospitalization time and total hospitalization cost were compared between the two groups. The preoperative and postoperative functions of the two groups were evaluated by Hospital for Sepcial Surgery (HSS) score and Lysholm score respectively, and the curative effects were compared within and between groups. RESULTS: All the patients in the two groups were followed up for at least 1 year. There were no complications such as infection and poor wound healing in both groups. There was significant difference in operation time between (120.25±9.55) min in group A and (106.63±8.85) min in group B (P<0.01). The average hospitalization days in group A was (10.60±1.64) days, while that in group B was (10.38±1.59) days. There was no significant difference between the two groups (P>0.05). The HSS score of group A increased from preoperative 32.95±5.03 to postoperative 84.70±5.72 (P<0.01), and that of group B increased from preoperative 33.81±4.10 to postoperative 85.00±5.25 (P<0.01). The Lyshlom score in group A increased from preoperative 21.10±3.46 to postoperative 80.25±5.75 (P<0.01), and in group B increased from preoperative 21.56±3.01 to postoperative 80.00±4.30(P<0.01). There was no significant difference in preoperative and postoperative scores between the two groups(P>0.05). CONCLUSION: There was no significant difference in the average hospitalization days between the two groups, but the operation time in group A was longerthan that in group B, and the hospitalization cost in group B was higher than that in group A. There was no difference in HSS score and Lysholm score before and follow-up for a certain period of time after operation.

Application of Triggered EMG in the Intraoperative Neurophysiological Monitoring of Posterior Percutaneous Endoscopic Cervical Discectomy.

OBJECTIVE: To describe the rationale and application of triggered EMG (T-EMG) in intraoperative neurophysiological monitoring, and to explore the efficacy and safety of posterior percutaneous endoscopic cervical discectomy (PPECD) in the treatment of cervical spondylotic radiculopathy (CSR) under multimodal intraoperative neurophysiological monitoring (IOM). METHODS: This study was a retrospective cohort control study. The clinical data of 74 patients with single-segment CSR from June 2015 to August 2018 were analyzed retrospectively, of whom 35 underwent IOM-assisted PPECD with triggered EMG (T-EMG group), while 39 were subjected to IOM-assisted PPECD alone (IOM group). Operation time, hospital stay, and complications were recorded for both groups. The curative effect was evaluated according to the Visual Analog Scale (VAS) of neck and arm pain, Japanese Orthopaedic Association (JOA) score, and modified MacNab scale. RESULTS: Operations were successful and all patients were followed up for at least 24 (average 31.77 ± 9.51) months with no patient lost to follow-up. No significant difference was found in preoperative baseline data between the T-EMG and the IOM group (P > 0.05). Also, no significant difference was found in the operation time between the T-EMG (108.29 ± 11.44 min) and the IOM (110.13 ± 12.70 min) (P > 0.05) group, but the difference in hospital stay (T-EMG: 5.66 ± 0.99 days; IOM: 7.10 ± 1.43 days) was statistically significant (P < 0.05). The VAS for the neck and upper limbs in the two groups at 1 month post-operation (T-EMG: 2.09 ± 1.07, 2.26 ± 0.92; IOM:2.18 ± 1.05, 2.31 ± 0.77) and the last follow-up (T-EMG: 0.83 ± 0.62, 0.86 ± 0.55; IOM: 0.90 ± 0.50, 0.87 ± 0.61) were significantly different from the preoperative scores (T-EMG: 6.14 ± 1.09, 7.17 ± 1.04; IOM: 6.18 ± 1.28, 7.15 ± 1.23) (P < 0.05). However, no significant difference was found between the two groups (P > 0.05). The 1-month postoperative JOA scores for the two groups (12.69 ± 0.76; 12.59 ± 0.82) and those at the last follow-up (14.60 ± 0.77; 14.36 ± 0.78) were significantly different from the preoperative scores (11.09 ± 0.98; 11.05 ± 0.89) (P < 0.05), but the difference between the two groups was not significant (P > 0.05). One patient in the T-EMG group developed a transient aggravation of symptoms on the first day after surgery. In the IOM group, three patients had intraoperative cerebrospinal fluid leakage, and symptoms of C5 nerve root paralysis were presented in four patients following surgery. Compared with the IOM group, the T-EMG group had fewer complications (1/35; 7/39, P < 0.05). At the last follow-up, the modified MacNab criteria were 91.43% (32/35) and 89.7% (35/39) for the T-EMG group and IOM group, respectively. CONCLUSIONS: Triggered EMG prevents the occurrence of neurological complications, which not only aids PPECD for CSR treatment in achieving satisfactory results, but also reduces average hospital stay and complication rates.

Percutaneous Endoscopic Unilateral Laminotomy and Bilateral Decompression for Lumbar Spinal Stenosis.

To introduce a new surgery, percutaneous endoscopic unilateral laminotomy and bilateral decompression (Endo-ULBD) using visual trepan, and investigate its efficacy and safety in elderly patients with lumbar spinal stenosis. In our retrospective study, a total of 69 patients were enrolled between March 2018 and September 2018; 31 patients were treated with Endo-ULBD and 38 patients were treated with posterior lumbar interbody fusion surgery (PLIF). The operation time, intraoperative blood loss, and hospitalization duration were compared between the two groups. A visual analog scale (VAS) was used to evaluate the degree of pain. The Oswestry Disability Index (ODI) and European Quality of Life-5 Dimensions (EQ-5D) were used to evaluate lumbar function and quality of life, respectively. Lumbar X-ray, computed tomography (CT) and magnetic resonance imaging (MRI) were performed postoperatively at different time points. MacNab's outcome assessment and perioperative complications were also documented. The surgeon completed all surgeries successfully, and all 69 patients were followed up. The operative time of the Endo-ULBD group was 60.68 ± 0.47 min, while that of the PLIF group was 120.23 ± 10.24 min. The operative time of the Endo-ULBD group was shorter than that of the PLIF group, and the difference was statistically significant (P < 0.001). The volume of intraoperative blood loss was 47.25 ± 0.43 mL in the Endo-ULBD group and 256.90 ± 20.83 mL in the PILF group (P < 0.001). The length of hospital stay in the Endo-ULBD group was 5.12 ± 1.60 days and that in the PILF group was 10.54 ± 1.82 days (P < 0.001). The VAS scores at postoperative 1 day, 3 months, 6 months, final follow-up (Endo-ULBD: 6.58 ± 0.65, 4.55 ± 0.54, 2.78 ± 0.24, 1.31 ± 0.78; PLIF: 7.19 ± 1.14, 4.80 ± 0.13, 2.71 ± 0.83, 1.29 ± 0.56) were significantly improved compared with those before surgery (Endo-ULBD: 8.63 ± 0.37; PLIF: 8.31 ± 1.34). The ODI and EQ-5D scores of lumbar function and quality of life at each time point after surgery (Endo-ULBD ODI: 30.29% ± 0.47%, 23.35% ± 0.95%, 19.45% ± 0.81%, 10.84% ± 0.36%; EQ-5D: 0.38 ± 0.15, 0.45 ± 0.17, 0.63 ± 0.14, 0.71 ± 0.20; PLIF ODI: 33.56% ± 1.58%, 25.69% ± 2.69%, 20.01% ± 1.49%, 10.72% ± 0.29%; EQ-5D: 0.33 ± 0.03, 0.39 ± 0.05, 0.62 ± 0.07, 0.72 ± 0.10) were significantly improved compared with those before surgery (Endo-ULBD: 44.56 ± 1.32, 0.33 ± 0.07; PLIF: 43.79 ± 1.91, 0.31 ± 0.09, respectively), with statistically significant differences (P < 0.05); however, there was no significant difference between the two groups at the last follow-up (P > 0.05). At the last follow-up, the excellent and good efficacy rate was 90.3% (28/31) in the Endo-ULBD group and 89.4% (34/38) in the PILF group (χ2 = 0.089, P = 0.993). No mortality, irreversible nerve injury, or even paralysis occurred in either group. Endo-ULBD for lumbar spinal stenosis has the advantages of less trauma, a shortened operation time, and rapid recovery and is an effective alternative for the treatment of lumbar spinal stenosis. Strict surgical indications, reasonable surgical plans, and experienced surgeons are important factors to ensure safety and satisfactory postoperative efficacy.

Early Clinical Evaluation of Percutaneous Full-endoscopic Transforaminal Lumbar Interbody Fusion with Pedicle Screw Insertion for Treating Degenerative Lumbar Spinal Stenosis.

OBJECTIVE: To compare the clinical efficacy of percutaneous full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) with percutaneous pedicle screws (PPSs) performed by using a visualization system with that of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for the treatment of degenerative lumbar spinal stenosis (LSS). METHODS: From June 2017 to May 2018, the data of a total of 78 patients who met the selection criteria were retrospectively reviewed and were divided into the Endo-TLIF group (40 cases) and the MIS-TLIF group (38 cases) according to the surgical method used. The visual analog scale (VAS) and the Japanese Orthopaedic Association (JOA) scale were administered preoperatively and at the 1-week, 3-month, and 1-2-year follow-ups. The fusion rate and major complications, including revision, were also recorded. RESULTS: All the patients were followed up for 24 to 34 months, with an average follow-up of 30.7 months. The intraoperative blood loss and length of hospital stay for the Endo-TLIF group (60.56 ± 0.36 mL, 8.12 ± 0.92 days, respectively) were statistically significantly lower than those for the MIS-TLIF group (65.47 ± 0.91 mL, 9.66 ± 1.34 days, respectively) (P < 0.05). The VAS and JOA scores of the patients in the two groups at postoperative 1 week, 3 months, 1 year, 2 years (Endo-TLIF VAS: 4.16 ± 0.92, 3.72 ± 1.54, 1.32 ± 0.45, 1.29 ± 0.34; JOA:16.71 ± 0.99, 19.86 ± 0.24, 24.91 ± 0.97, 25.88 ± 0.52; MIS-TLIF VAS: 4.17 ± 1.41, 2.98 ± 0.91, 1.54 ± 0.32, 1.33 ± 0.18; JOA: 16.67 ± 0.67, 19.58 ± 0.65, 25.33 ± 0.73, 25.69 ± 0.33) were statistically significantly improved from the preoperative scores (Endo-TLIF: 8.45 ± 1.44, 14.36 ± 0.56; MIS-TLIF: 8.11 ± 0.93, 14.45 ± 0.34, respectively) (P < 0.01). The VAS and JOA scores of the Endo-TLIF group were statistically significantly better than those of the MIS-TLIF group at 3 months and 1 year after surgery (P < 0.05). There were no statistically significant differences in the scores between the two groups at any of the other time points (P > 0.05). There was no significant difference in the intervertebral altitude between the two groups at the 3-month (11.36 ± 0.23, 11.21 ± 0.42, respectively) or final follow-up (10.88 ± 0.64, 10.81 ± 0.39, respectively) (P > 0.05). Dural tears, cerebrospinal fluid leakage, infection, and neurologic injury did not occur. Both groups showed good intervertebral fusion at the last follow-up. The intervertebral fusion rate was 97.5% (39/40) in the Endo-TLIF group and 94.7% (36/38) in the MIS-TLIF group, with no statistically significant difference between the two groups (χ2 = 0.118, P = 0.731). At the final follow-up, the modified MacNab's criteria were 92.5% and 89.5% between the two groups. CONCLUSION: Endo-TLIF with percutaneous pedicle screws (PPS) performed by using a visualization system for lumbar degenerative disease may be regarded as an efficient alternative surgery for degenerative lumbar spinal stenosis. It is a safe and minimally invasive way to perform this surgery and has shown satisfactory clinical outcomes.

The effect of tourniquet uses on total blood loss, early function, and pain after primary total knee arthroplasty: a prospective, randomized controlled trial.

AIMS: The aim of this study was to examine whether tourniquet use can improve perioperative blood loss, early function recovery, and pain after primary total knee arthroplasty (TKA) in the setting of multiple-dose intravenous tranexamic acid. METHODS: This was a prospective, randomized clinical trial including 180 patients undergoing TKA with multiple doses of intravenous tranexamic acid. One group was treated with a tourniquet during the entire procedure, the second group received a tourniquet during cementing, and the third group did not receive a tourniquet. All patients received the same protocol of intravenous tranexamic acid (20 mg/kg) before skin incision, and three and six hours later (10 mg/kg). The primary outcome measure was perioperative blood loss. Secondary outcome measures were creatine kinase (CK), CRP, interleukin-6 (IL-6), visual analogue scale (VAS) pain score, limb swelling ratio, quadriceps strength, straight leg raising, range of motion (ROM), American Knee Society Score (KSS), and adverse events. RESULTS: The mean total blood loss was lowest in the no-tourniquet group at 867.32 ml (SD 201.11), increased in the limited-tourniquet group at 1024.35 ml (SD 176.35), and was highest in the tourniquet group at 1,213.00 ml (SD 211.48). The hidden blood loss was lowest in the no-tourniquet group (both p < 0.001). There was less mean intraoperative blood loss in the tourniquet group (77.48 ml (SD 24.82)) than in the limited-tourniquet group (137.04 ml (SD 26.96)) and the no-tourniquet group (212.99 ml (SD 56.35); both p < 0.001). Patients in the tourniquet group showed significantly higher levels of muscle damage and inflammation biomarkers such as CK, CRP, and IL-6 than the other two groups (p < 0.05). Outcomes for VAS pain scores, limb swelling ratio, quadriceps strength, straight leg raising, ROM, and KSS were significantly better in the no-tourniquet group at three weeks postoperatively (p < 0.05), but there were no significant differences at three months. No significant differences were observed among the three groups with respect to transfusion rate, thrombotic events, or the length of hospital stay. CONCLUSION: Patients who underwent TKA with multiple doses of intravenous tranexamic acid but without a tourniquet presented lower total blood loss and hidden blood loss, and they showed less postoperative inflammation reaction, less muscle damage, lower VAS pain score, and better early knee function. Our results argue for not using a tourniquet during TKA.Cite this article: Bone Joint Res 2020;9(6):322-332.

[Clinical observation of high tibial osteotomy for knee osteoarthritis:10 years follow-up].

OBJECTIVE: To explore long-term following-up clinical effects of lateral closed high tibial osteotomy for the treatment of knee osteoarthritis. METHODS: Twenty patients with medial unicompartmental knee osteoarthritis were treated with lateral closed high tibial osteotomy and screw fixation from June 2005 to December 2015. Among them, including 17 females and 3 males, aged from 43 to 76 years old with an average of (57.80±8.05) years old. VAS score and KSS score were applied to evaluate recovery degree of pain and function before operation and after operation at 1, 5 and 10 years, and postoperative complications were observed. RESULTS: Sixteen patients were followed-up, the time ranged from 9 to 11(10.0±0.8) years, 4 patients were loss to follow-up. Preoperative VAS score was 7.88±1.15 and decreased to 3.19±0.91, 3.44±0.96, 3.69±1.20 at 1, 5 and 10 years after operation, and there were statistical differences in VAS score between before and after operation at different time points (P<0.05). Clinical score of KSS increased from 61.94±5.74 before opertaion to 75.50±4.62, 80.13±3.97, 77.38±6.40 at 1, 5 and 10 years after operation, and there were statistical differences in clinical score of KSS between before and after operation at different time points(P<0.05); functional score of KSS increased from 62.81±13.03 before operation to 77.50±8.56, 81.88±6.55, 76.88±10.78, and there were statistical differences in functional score of KSS between before and after operation at different time points(P<0.05). All incisions healed well without complications such as fibula nerve injury and fracture nonunion. CONCLUSIONS: Lateral closed high tibial osteotomy and screw fixation for knee osteoarthritis could receive good clinical results, stop and delay progress of knee osteoarthritis, and long-term following-up could achieve the same effect as total knee arthroplasty.

MicroRNA-185 inhibits the growth and proliferation of osteoblasts in fracture healing by targeting PTH gene through down-regulating Wnt/ß -catenin axis: In an animal experiment.

Fracture healing is a repair process of a mechanical discontinuity loss of force transmission, and pathological mobility of bone. Increasing evidence suggests that microRNA (miRNA) could regulate chondrocyte, osteoblast, and osteoclast differentiation and function, indicating miRNA as key regulators of bone formation, resorption, remodeling, and repair. Hence, during this study, we established a right femur fracture mouse model to explore the effect microRNA-185 (miR-185) has on osteoblasts in mice during fracture healing and its underlying mechanism. After successfully model establishment, osteoblasts were extracted and treated with a series of mimics or inhibitors of miR-185, or siRNA against PTH. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis were performed to determine the levels of miR-185, PTH, ß-catenin and Wnt5b. Cell viability, cycle distribution and apoptosis were detected by means of MTT and flow cytometry assays. Dual luciferase reporter gene assay verified that PTH is a target gene of miR-185. Osteoblasts transfected with miR-185 mimics or siRNA against PTH presented with decreased levels of PTH, ß-catenin and Wnt5b which indicated that miR-185 blocks the Wnt/ß -catenin axis by inhibiting PTH. Moreover, miR-185 inhibitors promoted the osteoblast viability and reduced apoptosis with more cells arrested at the G1 stage. MiR-185 mimics were observed to have inhibitory effects on osteoblasts as opposed to those induced by miR-185 inhibitors. Above key results indicated that suppression of miR-185 targeting PTH could promote osteoblast growth and proliferation in mice during fracture healing through activating Wnt/ß -catenin axis.

Knockdown of Ski decreased the reactive astrocytes proliferation in vitro induced by oxygen-glucose deprivation/reoxygenation.

Glia scar is a pathological marker in late phase of brain ischemia disease, which constitutes a major physical biochemical barrier to impede axonal regrowth. Astrocytes are known to be critically involved in the formation of glial scar. However, their response to ischemia and their role in neuroprotection after central nervous system (CNS) injury are not completely clear. Recently, we have demonstrated for the first time that Ski was up-regulated in reactive astrocytes after spinal cord injury in vivo and in vitro, which indicates Ski may be a new molecule that control astrocytes biologic properties after CNS injury. However, its role in the process of reactive astrogliosis after cerebral ischemia and its definite mechanism still remains unknown. This study is to elucidate the role of Ski in reactive astrocytes induced by oxygen-glucose deprivation/reoxygenation (OGD/R) model in vitro. The expression of Ski was proved to be up-regulated in OGD/R model. Meanwhile, Up-regulation of Ski was accompanied with high ratio of EdU (+) cells and up-expression of related proteins including GFAP, PCNA, CDK4, and CyclinD1, which demonstrated the distinct activation and proliferation of astrocytes after stimulation by OGD/R. Astrocytes were transfected with Ski-specific siRNA to knockdown Ski expression and subsequently attenuated OGD-induced astrocyte proliferation. Our results also showed that Ski down-regulation could suppress the activity of the Ras-Raf-ERK1/2 signaling pathway. Together, knockdown of Ski can effectively inhibit the proliferation of reactive astrogliosis via suppressing the Ras-Raf-ERK1/2 pathway. These findings indicated that maybe Ski is a promising therapeutic target for cerebral ischemic injury.

Comparison of Early Functional Recovery After Total Hip Arthroplasty Using a Direct Anterior or Posterolateral Approach: A Randomized Controlled Trial.

BACKGROUND: Controversy exists as to whether early functional outcomes differ after total hip arthroplasty performed using the direct anterior approach (DAA) or the posterolateral approach (PLA). METHODS: One hundred twenty patients were enrolled in this study and were divided into 2 groups based on surgical approach. Group A included patients who had a total hip arthroplasty with a DAA, whereas group B included those with a PLA. Patients were randomized into the DAA or PLA groups (n = 60), and perioperative and postoperative outcomes were recorded. RESULTS: When compared with the PLA, the DAA had a shorter incision length (9.1 vs 13.1 cm; P < .01), shorter hospital stay (2.8 vs 3.3 days, P = .04), and lower self-reported pain. Both serum inflammatory and muscle damage markers were lower in the DAA group. However, the PLA had shorter operative times (65.5 vs 83.3 min, P = .03) and less intraoperative blood loss (123.8 vs 165.9 mL, P = .04). The DAA had significantly lower variance in cup inclination and anteversion. Similar rates of intraoperative complications were identified in the 2 groups. The DAA was associated with better functional recovery at 3 months based on the Harris hip score, University of California Los Angeles activity score, and gait analysis; however, functional recovery at 6 months was similar between the 2 groups. CONCLUSION: We found functional advantages in early recovery after the DAA compared with the PLA. The DAA can offer rapid functional recovery with less muscle damage, greater pain relief, and lower variance in cup inclination and anteversion. However, no functional difference was found at 6 months follow-up.

Narrow Intercondylar Notch and Anterior Cruciate Ligament Injury in Female Nonathletes with Knee Osteoarthritis Aged 41-65 Years in Plateau Region.

BACKGROUND: Few data are available concerning intercondylar notch dimensions in female nonathletes with knee osteoarthritis (OA) in plateau region. The aim of this study was to assess the relation of intercondylar notch morphology to anterior cruciate ligament (ACL) injuries in female nonathletes with knee OA aged 41-65 years from the Chinese Loess Plateau. METHODS: The study was conducted on 330 patients with ACL injury (aged 31-65 years; 159 males, 171 females), 141 patients with OA (aged 31-65 years; 59 males, 82 females), and 89 female healthy controls (aged 41-65 years), and this evaluation included identifying the distribution of patients with OA or ACL injury and measuring the intercondylar notch width indexes (NWIs). RESULTS: There was a significant rising trend in patients with OA (the Kellgren and Lawrence grade = 3) with ACL injury (OA-S + ACL) aged 41-65 years, especially in females. We found that the notches of OA-S + ACL had a smaller NWI compared with control and OA without ACL injury (OA-S-only, P = 0.000, 95% confidence interval [CI] = -0.059--0.030; P = 0.000, 95% CI = -0.049--0.016). A similar trend was found in notch shape index (NSI), but not in notch depth index and the cross-sectional area. The cutoff of NWI and NSI value was 0.26, and 0.65, and area under the receiver operating characteristic curve was 0.82, and 0.79, respectively. Further study displayed a significant correlation between a reduced NWI and NSI and OA-S + ACL (P = 0.000, χ2 = 14.012; P = 0.000, χ2 = 14.286). CONCLUSION: A narrower intercondylar notch and a plateau environment are risk factors of predisposing female nonathletes with knee OA to ACL injury aged 41-65 years.

[Reconstruction of complex proximal tibial defects using the long-stem tibial component combined with metallic wedge].

OBJECTIVE: To investigate results of total knee arthroplasty using the long-stem tibial component combined with metallic wedge of knee prosthesis for the treatment of proximal defects. METHODS: From January 2011 to May 2013, 10 patients (11 knees) were treated with total knee arthroplasties using the long-stem tibial component with metallic tibial wedge of knee prosthesis. All the patients were female and the average age was 67 years old (ranged, 60 to 77 years old). All the patients were osteoarthritis. All the patients were classified as T2A style. The patients were evaluated according to knee score system (KSS). RESULTS: All the patients were followed up for 12 months on average (ranged 3 to 29 months). The clinical outcome was assessed using KSS score, including knee pain score, knee stability score, knee range of motion score and knee walking score, knee stairs score. There were significantly differences at 6 weeks, 3 months, 6 months and 12 months between pre-and postoperative KSS score. CONCLUSION: The mechanical stability of tibial fixation in primary TKA is significantly increased by using the long-stem tibial component with metallic wedge of knee prosthesis, even in the presence of poor proximal bone.

The offset of the tibia plateau of osteoarthritis patients: a single-center study.

Component position and good fixation are important factors determining the success of a primary or revision total knee arthroplasty (TKA). The aim of this study was to measure the anatomic features of the tibial plateau and to assess variations in the offset of the tibial shaft from the tibial plateau in osteoarthritis (OA) patients. Computed tomography (CT) scan results were obtained from 126 knees of 121 OA patients (72 female, 49 male) with an average age of 65 ± 7 years. The anatomic features of the tibial plateau were measured and analyzed using three-dimensional reconstruction information derived from a 64-slice spiral CT. The results showed significant variations in proximal tibial anatomy among the subjects. The mean offset was 7.61 ± 3.04 mm at the resection just distal to the subchondral bone. The mean anteroposterior and mediolateral dimensions of the tibial plateau were 53.05 ± 4.82 mm and 70.42 ± 8.33 mm, respectively, at the resection just distal to the subchondral bone. The tibial shaft axis was located anterolateral to the center of the tibial plateau in 62% of knees, while in 36% of these knees, it was located anterior medial to the center of the tibial plateau at the resection just distal to the subchondral bone. Our study shows that anatomic variations should be fully evaluated before performing TKA. A wide range of implant sizes is thus necessary for optimum replacement.

[Relationship between coronal intercondylar notch width index and osteoarthritis].

OBJECTIVE: To study the relationship between knee osteoarthritis (OA) and intercondylar notch narrowing based on the notch width index. METHODS: Magnetic resonance (MR) images were collected from middle-aged and elderly patients with a definite diagnosis of knee OA, including 42 with mild OA and 37 with moderate to severe OA, with 70 healthy individuals serving as the control group. The notch width indexes NWI, NWI-A, and NWI-P on the coronal images at different levels were calculated, and the intercondylar notch was classified, according to the features on axial MR images, into types A, U, and W. The association of OA with NWI, NWI-A, NWI-P, and notch type was determined, and the cutoff values were obtained based on the ROC curves at different levels as indicators for diagnosis of intercondylar notch stenosis. RESULTS: In the control, mild OA, moderate to severe OA groups, the NWI value on coronal MR images were 0.252±0.019, 0.251±0.017, and 0.240±0.020, NWI-A were 0.261±0.024, 0.259±0.023, and 0.245±0.023, and NWI-P were 0.271±0.026, 0.270±0.024, and 0.254±0.022, respectively. Patients with moderate to severe OA had significantly smaller NWI, NWI-A, and NWI-P than the other two groups (P<0.05), and a significant association was found between NWI values at each level and the occurrence of moderate to severe OA (P<0.01). A NWI value<0.248, NWI-A<0.256, and NWI-P<0.266 supported a diagnosis of intercondylar notch narrowing. Type A intercondylar notch was found in the majority of patients with intercondylar notch narrowing (P<0.05). CONCLUSION: Patients with moderate to severe OA have significant intercondylar notch narrowing, and patients with a type A intercondylar notch are more likely to have intercondylar notch narrowing than those with type U notch.

Does Arthroplasty Provide Better Outcomes Than Internal Fixation At Mid- and Long-term Followup? A Meta-analysis.

BACKGROUND: Arthroplasty has been shown to be superior regarding low risk of reoperation and better function score to internal fixation for treatment of displaced femoral neck fractures at short-term followup. However, there are unanswered questions regarding the efficacy of arthroplasty in the longer term compared with internal fixation. QUESTIONS/PURPOSES: We performed a meta-analysis comparing arthroplasty (hemiarthroplasty or THA) with internal fixation in patients with displaced femoral neck fractures with respect to (1) mortality, (2) reoperation, (3) functional recovery, and (4) complications, including only randomized trials with a minimum of 4 years followup. METHODS: Computerized databases, including PubMed (MEDLINE), EMBASE, Cochrane Register of Controlled Trials databases, and Web of Science™ were searched for studies published from the inception date for each database to March 2014. Eleven randomized controlled trials that compared arthroplasty (either hemiarthroplasty or THA) with internal fixation for treatment of patients with a femoral neck fracture were included in our analysis. The quality of the trials was assessed according to the Cochrane Handbook and meta-analyses were conducted using RevMan 5.2 software from the Cochrane Collaboration. The heterogeneity among studies was evaluated by the I-squared index (I2) and publication bias was assessed using forest plots. RESULTS: There were no differences between the internal fixation and arthroplasty groups for patient mortality at mid-term (48.4% vs 46.8%) or long-term followup (83.2% vs 81.5%). Arthroplasty was associated with a lower risk of reoperation at mid-term (7.2% vs 39.8%; relative risk [RR]=0.10; 95% CI, 0.06-0.07) and at long-term followup (14.3% vs 43.8%; RR=0.10; 95% CI, 0.06-0.07). Arthroplasty was associated with better functional recovery at mid-term followup (standard mean difference [SMD]=0.55; 95% CI, 0.02-1.09), whereas function at long-term followup (SMD=0.14; 95% CI, -0.35 to 0.62) was not different between the arthroplasty and internal fixation groups. There were no significant differences in subsequent ipsilateral fractures (1.5% vs 1.2%; RR=2.18; 95% CI, 0.32-14.67; p=0.42) and deep infections (2.7% vs 2.9%; RR=0.89; 95% CI, 0.40-2.01; p=0.78) between patients treated with arthroplasty and internal fixation. CONCLUSIONS: Based on our results, we found that compared with internal fixation, arthroplasty may result in a lower rate of subsequent reoperation at mid- and long-term followup, and better mid-term functional recovery. Future studies should investigate the mid- and long-term results of THAs compared with hemiarthroplasty.

ERK5 signalling pathway is essential for fluid shear stress-induced COX-2 gene expression in MC3T3-E1 osteoblast.

Bone cells respond to various mechanical stimuli including fluid shear stress (FSS) in vitro. Induction of cyclooxygenase-2 (COX-2) is thought to be important for the anabolic effects of mechanical loading. Recently, extracellular-signal-regulated kinase 5 (ERK5) has been found to be involved in multiple cellular processes. However, the relationship between ERK5 and the induction of COX-2 is still unknown. Here, we investigated the potential involvement of ERK5 in the response of pre-osteoblastic MC3T3-E1 cells upon FSS. MC3T3-E1 cells were subjected to 12 dyn/cm(2) FSS. Then, we established a ERK5 small interfering RNA (siRNA) transfected cell line using the MC3T3-E1 cells. After the successful transfection confirmed by real-time reverse transcription-polymerase chain reaction and Western blotting, the expression of COX-2, cAMP response element-binding protein (CREB), and nuclear factor kappa B cells (NF-κB) were assayed for downstream effectors of activated ERK5 under FSS by Western blotting. Our results showed that FSS could stimulate COX-2 activity, and induce the phosphorylation of ERK5, CREB, and NF-κB. When the MC3T3-E1 cells were transfected using siRNA before exposure to FSS, COX-2 activity was suppressed, and the phosphorylation of CREB and NF-κB was significantly downregulated. In summary, we demonstrated that ERK5 pathway is essential in the induction of COX-2 gene.