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Poly(methyl methacrylate) (PMMA) bone cement has been widely used in orthopedic surgeries including total hip/knee replacement, vertebral compression fracture treatment, and bone defect filling. However, aseptic loosening of the interface between PMMA bone cement and bone often leads to failure. Hence, the development of modified PMMA that facilitates the growth of bone into the modified PMMA bone cement is key to reducing the incidence of aseptic loosening. In this study, MgAl-layered double hydroxide (LDH) microsheets modified PMMA (PMMA&LDH) bone cement with superior osseointegration performance has been synthesized. The maximum polymerization reaction temperature of PMMA&LDH decreased by 7.0 and 11.8 °C, respectively, compared with that of PMMA and PMMA&COL-I (mineralized collagen I modified PMMA). The mechanical performance of PMMA&LDH decreased slightly in comparison with PMMA, which is beneficial to alleviate stress-shielding osteolysis, and indirectly promote osseointegration. The superior osteogenic ability of PMMA&LDH has been demonstrated in vivo, which boosts bone growth by 2.17-and 18.34-fold increments compared to the PMMA&COL-I and PMMA groups at 2 months, postoperatively. Moreover, transcriptome sequencing revealed four key osteogenic pathways: p38 MAPK, ERK/MAPK, FGF, and TGF-β, which were further confirmed by IPA, qPCR, and Western blot assays. Hence, LDH-modified PMMA bone cement is a promising biomaterial to enhance bone growth with potential applications in relevant orthopedic surgeries.

In this study, we investigated the role of macrophage stimulating 1 (Mst1) and the AMPK-Sirt1 signaling pathway in the oxidative stress-induced mitochondrial dysfunction and apoptosis seen in rheumatoid arthritis-related fibroblast-like synoviocytes (RA-FLSs). Mst1 mRNA and protein expression was significantly higher in hydrogen peroxide (H 2 O 2 )-treated RA-FLSs than untreated controls. H 2 O 2 treatment induced the mitochondrial apoptotic pathway by activating caspase3/9 and Bax in the RA-FLSs. Moreover, H 2 O 2 treatment significantly reduced mitochondrial membrane potential and mitochondrial state-3 and state-4 respiration, but increased reactive oxygen species (ROS). Mst1 silencing significantly reduced oxidative stress-induced mitochondrial dysfunction and apoptosis in RA-FLSs. Sirt1 expression was significantly reduced in the H 2 O 2 -treated RA-FLSs, but was higher in the H 2 O 2 -treated Mst1-silenced RA-FLSs. Pretreatment with selisistat (Sirt1-specific inhibitor) or compound C (AMPK antagonist) significantly reduced the viability and mitochondrial function in H 2 O 2 -treated Mst1-silenced RA-FLSs by inhibiting Sirt1 function or Sirt1 expression, respectively. These findings demonstrate that oxidative stress-related upregulation and activation of Mst1 promotes mitochondrial dysfunction and apoptosis in RA-FLSs by inhibiting the AMPK-Sirt1 signaling pathway. This suggests the Mst1-AMPK-Sirt1 axis is a potential target for RA therapy.

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Objective: To investigate the effects of improved perioperative sleep on pain, analgesic consumption, and postoperative nausea and vomiting (PONV) in patients who were undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA).Methods: Original studies published from 1 January 1970 to 30 September 2020 were queried in three unique databases using a common search term. The searches sought randomized controlled trials (RCT) investigating the effectiveness of sleep quality or quantity interventions for pain control early after TKA or THA. Grey literature was also searched by screening trial registers. There was no limitation on published language and patients. Two reviewers then assessed studies for eligibility. Eligible studies should have primary outcomes including perioperativeWe have comfirmed the edits. visual analogue scale (VAS) pain score and analgesic consumption; and secondary outcomes including side effects, such as PONV. Data extracted from the literature were abstracted into a comma-separated database spreadsheet using Microsoft Excel. A meta-analysis was then performed. Pooled statistics were calculated with weighting by inverse variance assuming a random effect model. I 2 was calculated as a quantifier of heterogeneity and interpreted according to the Cochrane manual. All data analysis was performed using Revman software.Results: From a total of 1285 potential records identified in the electronic search, six studies eventually fulfilled the eligibility criteria. The six controlled RCTs consisted of 207 patients in the sleep-improving group and 209 patients in the control group. The severity of rest pain was significantly lower in the sleep-improving group compared with the control group at day 1 and day 3 postoperatively; the severity of active pain was significantly lower in the sleep-improving group compared with the control group at day 3 postoperatively. Data concerning analgesic drugs could not undergo a meta-analysis due to the difference of eligible studies. No significant difference was found in the incidence of PONV between the sleep-improving group and the control group. Conclusion:Improved perioperative sleep, regardless of quality or quantity, could significantly reduce the pain level at the early stage after TKA or THA, thus the total amount of analgesic drugs consumed was decreased, without significant increase in the incidence of PONV.

Background: Total knee arthroplasty (TKA) has brought hope to patients with malignant knee joint diseases. Infection is one of the serious complications after TKA, and the purpose of this study was to use bibliometrics to analyze the current research status of infection after this surgery, to unmask any deficiencies with current research, and to provide references for future researchers.Methods: We used the Science Citation Index Expanded (SCI-E) database in the Web of Science Core Collection (WOSCC) as the data source, using the search terms "total knee arthroplasty" and "infection" respectively. The "And" operation was performed on the search results of the two subject terms, and the intersection of the two search results was taken as the final search result. CiteSpace software was used to analyze the results. Results:The search results consisted of 5,600 documents, with a total citation frequency of 148,871. The average number of citations for each literature was 26.58, and the h-index was 142. The top five countries in the number of publications were the United States, China, Germany, the United Kingdom, and Spain, while the top five centrally ranked countries were the United States, the Netherlands, Germany, the United Kingdom, and France. The top five institutions with the number of publications were

The techniques available to locate the femoral tunnel during anterior cruciate ligament (ACL) reconstruction have notable limitations. To evaluate whether the femoral tunnel center could be located intraoperatively with a ruler, using the posterior apex of the deep cartilage (ADC) as a landmark. This retrospective case series included consecutive patients with ACL rupture who underwent arthroscopic single-bundle ACL reconstruction at the Department of Orthopedics, Beijing Tongren Hospital between January 2014 and May 2018. During surgery, the ADC of the femoral lateral condyle was used as a landmark to locate the femoral tunnel center with a ruler. Three-dimensional computed tomography (CT) was performed within 3 days after surgery to measure the femoral tunnel position by the quadrant method. Arthroscopy was performed 1 year after surgery to evaluate the intra-articular conditions. Lysholm and International Knee Documentation Committee (IKDC) scores were determined before and 1 year after surgery. The final analysis included 82 knees of 82 patients (age = 31.7 ± 6.1 years; 70 males). The femoral tunnel center was 26 ± 1.5% in the deep-shallow (x-axis) direction and 31 ± 3.1% in the high-low (y-axis) direction, close to the “ideal” values of 27 and 34%. Lysholm score increased significantly from 38.5 (33.5–47) before surgery to 89 (86–92) at 1 year after surgery (p < 0.001). IKDC score increased significantly from 42.5 (37–47) before surgery to 87 (83.75–90) after surgery (p < 0.001). Using the ADC as a landmark, the femoral tunnel position can be accurately selected using a ruler.