Insightful Understanding of Synergistic Oxygen Reduction on PtCo3(111) Toward Zinc-Air Batteries.

Theory-guided materials design is an effective strategy for designing catalysts with high intrinsic activity whilst minimizing the usage of expensive metals like platinum. As proof-of-concept, herein it demonstrates that using density functional theory (DFT) calculations and experimental validation that intermetallic PtCo3 alloy nanoparticles offer enhanced electrocatatalytic performance for the oxygen reduction reaction (ORR) compared to Pt nanoparticles. DFT calculations established that PtCo3(111) surfaces possess better intrinsic ORR activity compared to Pt(111) surfaces, owing to the synergistic action of adjacent Pt and Co active sites which optimizes the binding strength of ORR intermediates to boost overall ORR kinetics. With this understanding, a PtCo3/NC catalyst, comprising PtCo3 nanoparticles exposing predominantly (111) facets dispersed on an N-doped carbon support, is successfully fabricated. PtCo3/NC demonstrates a high specific activity (3.4 mA cm-2 mgPt -1), mass activity (0.67 A mgPt -1), and cycling stability for the ORR in 0.1 M KOH, significantly outperforming a commercial 20 wt.% Pt/C catalyst. Moreover, a zinc-air battery (ZAB) assembled with PtCo3/NC as the air-electrode catalyst delivered an open-circuit voltage of 1.47 V, a specific capacity of 775.1 mAh gZn -1 and excellent operation durability after 200 discharge/charge cycles, vastly superior performance to a ZAB built using commercial Pt/C+IrO2 as the air-electrode catalyst.

Iron-Cobalt Phosphide Encapsulated in a N-Doped Carbon Framework as a Promising Low-Cost Oxygen Reduction Electrocatalyst for Zinc-Air Batteries.

The oxygen reduction reaction (ORR) plays a vital role in many next-generation electrochemical energy conversion and storage devices, motivating the search for low-cost ORR electrocatalysts possessing high activity and excellent durability. In this work, we demonstrate that iron-cobalt phosphide (FeCoP) nanoparticles encapsulated in a N-doped carbon framework (FeCoP@NC) represent a very promising catalyst for the ORR in alkaline media. The core-shell structured FeCoP@NC catalyst offered outstanding ORR activity with a half-wave potential (E1/2) of 0.86 V vs reversible hydrogen electrode (RHE) and excellent stability in a 0.1 M KOH electrolyte, outperforming commercial Pt/C and many recently reported noble-metal-free ORR electrocatalysts. The superiority of FeCoP@NC as an ORR electrocatalyst relative to Pt/C was further verified in prototype zinc-air batteries (ZABs), with the aqueous and flexible ZABs prepared using FeCoP@NC offering excellent stability, impressive open circuit voltages (1.56 and 1.44 V, respectively), and high maximum power densities (183.5 and 69.7 mW cm-2, respectively). Density functional theory calculations revealed that encapsulating FeCoP nanoparticles in N-doped carbon shells resulted in favorable electron penetration effects, which synergistically regulated the adsorption/desorption of ORR intermediates for optimal ORR performance while also boosting the electronic conductivity. Our findings offer valuable new insights for rational design of transition metal phosphide-based catalysts for the ORR and other electrochemical applications.

Electroacupuncture Activated Impaired Brain Areas and Improved Mental Status and Sleep Quality in Primary Insomnia Patients.

Objective: This study aimed to investigate the specific neurological mechanisms underlying the effects of electroacupuncture at Shenmen (Heart 7) with Neiguan (Pericardium 6) acupoints in patients with primary insomnia (PI). We sought to understand these mechanisms by comparing changes in areaal homogeneity (ReHo) before and after treatment in PI patients and healthy controls (HC). Methods: Between November 2019 and November 2021, we recruited 17 primary insomnia patients (PI group) and 20 matched healthy controls (HC group) as study subjects from Zhaoqing First People's Hospital. Before electroacupuncture treatment, all participants completed the Pittsburgh Sleep Quality Index (PSQI), Hamilton Depression Rating Scale (HAMD), and Hamilton Anxiety Rating Scale (HAMA) assessments. Resting-state magnetic resonance imaging (MRI) scans were conducted before and after two sessions of electroacupuncture at Shenmen and Neiguan acupoints. Results: Before treatment, primary insomnia patients showed higher PSQI (χ2=1.964; P = .017), HAMA (χ2=2.016; P = .027), and HAMD scores (χ2=2.367; P = .013) compared to healthy controls, and increased ReHo values were observed in the left amygdala, bilateral middle temporal gyrus, and left posterior cingulate gyrus in PI patients, while decreased ReHo values were found in the left posterior cingulate gyrus, right middle frontal gyrus, and right precuneus. After treatment, ReHo values increased in the left superior frontal gyrus, right parahippocampal gyrus, and right cingulate gyrus, while they decreased in the left amygdala and right angular gyrus. Primary insomnia disrupts brain areas in the default network, salience network, and parts of the affective cognitive network. Conclusion: Electroacupuncture at Shenmen and Neiguan acupoints partially activated impaired brain areas in patients with primary insomnia, leading to improvements in mental status and sleep quality. This offers a novel perspective for the clinical treatment of primary insomnia.

Arthroscopic Primary Repair for Partial Proximal Anterior Cruciate Ligament Tear in Military Personnel.

OBJECTIVE: To evaluate the short-term clinical outcomes of arthroscopic primary repair for partial proximal anterior cruciate ligament (ACL) tear in a young, active duty military population. DESIGN: Retrospective cohort study. SETTING: A national tertiary-level medical and academic institution. PATIENTS: Nineteen active duty military patients with partial proximal ACL tears and excellent tissue quality were included and 18 were finally analyzed. INTERVENTIONS: All patients underwent arthroscopic primary repair using a suture anchor technique between March 2014 and June 2016. MAIN OUTCOME MEASURES: Clinical outcomes were evaluated using anterior drawer test (ADT), Lachman test, pivot shift test, 3-km run test, 10 m × 5 shuttle run test, physical readiness test (PRT) score, Tegner activity score, Lysholm score, modified Cincinnati score, International Knee Documentation Committee (IKDC) subjective score, and magnetic resonance imaging. RESULTS: At final follow-up, 17 patients had negative ADT, Lachman, and pivot shift examination findings, and 1 patient had a 1+ ADT, negative Lachman, and pivot shift result. Mean 3-km run time at final follow-up was not statistically different from that preinjury (12:55 vs 12:39, P = 0.071), nor were the 10 m × 5 shuttle run time (23.4 vs 22.9, P = 0.235), PRT score (82.5 vs 85.1, P = 0.086), and Tegner activity score (7.8 vs 7.9, P = 0.083). Mean Lysholm score at final follow-up was significantly improved compared with that preoperative (93.1 vs 70.7, P < 0.001), so were the modified Cincinnati score (90.4 vs 58.6, P < 0.001) and IKDC subjective score (88.3 vs 67.4, P < 0.001). CONCLUSIONS: Arthroscopic primary repair can achieve short-term clinical success in high-demand military patients with partial proximal ACL tears and excellent tissue quality.

Is Primary Arthroscopic Repair Using the Pulley Technique an Effective Treatment for Partial Proximal ACL Tears?

BACKGROUND: Attention has recently been paid to primary arthroscopic repair to treat ACL tears because of the disadvantages associated with reconstruction. However, there remain many unanswered questions and concerns about its application in the treatment of ACL tears. QUESTIONS/PURPOSES: (1) Does primary arthroscopic repair using the pulley technique result in satisfactory ROM (a functional ROM with a flexion contracture of 30° or less), knee stability, and functional scores in patients with partial proximal ACL tears? (2) What complications are associated with primary arthroscopic repair using the pulley technique in patients with partial proximal ACL tears? METHODS: Between January 2014 and March 2016, we treated 23 patients surgically who had partial proximal ACL tears and excellent tissue quality (defined as a remnant with mild interstitial tearing and the ability to hold sutures). All patients meeting those two criteria were treated using primary arthroscopic repair using the pulley technique. During that period, this represented 13% (23 of 183) of the patients we treated surgically for an ACL tear. Patients were excluded if they had other ACL tear types, insufficient tissue quality (defined as a severely torn remnant that was not strong enough to hold sutures), multi-ligamentous injuries, or substantial arthrosis (chondromalacia greater than Outerbridge grade 3, most of which underwent conversion to ACL reconstruction). Clinical outcomes were assessed using ROM, the anterior drawer test, the Lachman test, Lysholm score, Tegner activity score, IKDC subjective score, and radiographs. Twenty-one patients were observed for a mean (range) period of 36 months (25-49), and two were lost to follow-up. RESULTS: At the most-recent follow-up examination, all patients achieved full extension and only one patient lacked full flexion, with a flexion contracture of 10°. Twenty patients had no instability on the anterior drawer test and Lachman test findings, and one patient had a 1 + anterior drawer test. The mean Lysholm score improved from a mean ± SD of 71 ± 9 before surgery to 94 ± 6 (mean difference 23 points [95% CI 20 to 25]; p < 0.001) at latest follow-up. The IKDC subjective score improved from 64 ± 10 to 86 ± 11 points (mean difference 22 points; p < 0.001). We found no difference in the Tegner score from before surgery to latest follow-up (6.3 ± 1.2 versus 6.1 ± 1.2; mean difference 0.2; p = 0.056). One patient re-ruptured his ACL 2 months after surgery in military training during an obstacle race. No complications such as infection, thrombosis, stiffness, patellofemoral pain, or implant failure were observed. CONCLUSIONS: Primary arthroscopic repair using the pulley technique can achieve short-term clinical success in a carefully selected (the selection process includes first identifying the ACL injury pattern preoperatively with MRI, then confirming the diagnosis under arthroscopy, and deciding whether to perform a repair intraoperatively) subset of patients with partial proximal ACL tears and excellent tissue quality (defined as a remnant with mild interstitial tearing and the ability to hold sutures). Despite the promising clinical outcomes of our study, this technique should not be widely adopted unless it has been compared directly with ACL reconstruction, so future studies should be conducted to compare the clinical outcomes between this technique and ACL reconstruction, and longer-term follow-up is necessary to identify whether there is deterioration in the clinical outcomes over time. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Clinical outcomes of a combined arthroscopic and mini-open Outerbridge-Kashiwagi procedure for elbow osteoarthritis.

BACKGROUND: To evaluate the short-term clinical outcomes of a modified Outerbridge-Kashiwagi (O-K) procedure in the treatment of elbow osteoarthritis. METHODS: Between January 2012 and December 2016, 27 patients with elbow osteoarthritis were treated with a modified O-K procedure combining mini-open and arthroscopic technique in our institution. All patients with primary osteoarthritis and post-traumatic degenerative osteoarthritis of the elbow were included in the study if they had undergone the modified O-K procedure. Clinical outcomes were assessed using the visual analog scale (VAS), degree of flexion, extension loss, arc of motion, Mayo Elbow Performance Score (MEPS), and radiographs. RESULTS: Twenty-five patients with a mean age of 47.2 years (range, 21-69 years) at surgery were followed up for a mean of 54.5 months (range, 27-86 months). The VAS improved from 8.0 ± 1.4 (range, 6-10) preoperatively to 1.3 ± 1.1 (range, 0-3) at the final follow-up (P < .001), degree of flexion from 115.2° ± 12.0° (range, 90°-135°) to 130.6° ± 6.3° (range, 120°-140°) (P < .001), extension loss from 31.2° ± 15.0° (range, 10°-60°) to 10.2° ± 7.7° (range, 0°-30°) (P < .001), arc of motion from 84.0° ± 18.8° (range, 55°-120°) to 120.4° ± 9.3° (range, 105°-135°) (P < .001), and MEPS from 55.8 ± 8.1 (range, 40-70) to 88.4 ± 7.2 (range, 70-100) (P < .001). Radiographs at the final follow-up showed that 9 patients (36%) had significant recurrence of bone formation within the fenestration of the olecranon fossa. One patient developed delayed-onset ulnar neuropathy, with only slight numbness in the ulnar nerve distribution 6 months after surgery. CONCLUSIONS: The modified O-K procedure is safe and effective in pain relief and function restoration in patients with elbow osteoarthritis.

Arthroscopic Fixation of Tibial Eminence Fractures: A Biomechanical Comparative Study of Screw, Suture, and Suture Anchor.

PURPOSE: To compare biomechanical outcomes of 4 different arthroscopic techniques for fixation of tibial eminence fractures. METHODS: Twenty-four skeletally mature, fresh-frozen cadaveric knees were divided into 4 comparison groups based on the fixation method: screw fixation (group A), traditional sutures fixation with 2 FiberWire sutures (group B), a modified suture technique with 2 FiberWire sutures that created neckwear knots to firmly trap the fracture fragment (group C), or suture anchors which was based on the suture bridge technique primarily used in the shoulder for repair of rotator cuff tears and greater tuberosity fractures (group D). A tibial eminence fracture was created in each knee for subsequent fixation. After fixation, each knee underwent cyclic loading of 100 N to assess the displacement change after 500 cycles of the fixation construct. Afterward, a single tensile failure test load was performed to assess the ultimate failure load, stiffness, and failure mode for each specimen. RESULTS: All specimens survived cyclic testing and were subsequently loaded to failure. Group C had the highest ultimate failure load (P < .05) and group D had the lowest displacement compared with the other 3 groups (P < .05). Different failure modes were found among the 4 groups. CONCLUSIONS: Suture fixation using the neckwear knots technique provides superior fixation with regard to higher ultimate failure load, and absorbable suture anchor fixation with the suture bridge technique provides less displacement under cyclic loading conditions. Both techniques exhibited superior biomechanical properties compared with traditional screw and suture fixation. CLINICAL RELEVANCE: The new techniques showed satisfactory biomechanical properties and provided more choice for surgeons in the treatment of tibial eminence fractures.

Comparison of Arthroscopic and Conservative Treatments for Knee Osteoarthritis: A 5-Year Retrospective Comparative Study.

PURPOSE: To compare the effectiveness of arthroscopic and conservative treatments in patients with knee osteoarthritis (KOA) with 5 years of follow-up. METHODS: Patients diagnosed with Kellgren-Lawrence grade 2 to 4 KOA who underwent arthroscopic or conservative treatment from May 2005 to May 2012 were included. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score was collected 1, 2, 3, 4, and 5 years after the initial treatment, and the number of patients who underwent total knee arthroplasty (TKA) at every time point was recorded. RESULTS: Three hundred eighty-two patients (168 in the conservative group and 214 in the arthroscopy group) were included. Five years after the initial treatment, 32 of the 214 patients who underwent arthroscopy (15.0%) compared with 30 of the 168 patients in the conservative treatment group (17.9%) ultimately underwent TKA, with no statistically significant difference between groups (P = .20). The WOMAC score was significantly lower in the arthroscopy group than in the conservative group at year 1 (24.33 ± 21.56 vs 36.43 ± 16.22, respectively) and year 2 (26.31 ± 17.84 vs 35.41 ± 19.21, respectively). There were no significant between-group differences at years 3, 4, and 5. CONCLUSIONS: Compared with conservative treatment, arthroscopy provided no benefit in decreasing or delaying arthroplasty surgery. However, arthroscopy had a greater ability to relieve symptoms at 1 and 2 years. Our results suggest that arthroscopy can relieve symptoms up to 2 years without elevating the risk of arthroplasty. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Is Arthroscopic Technique Superior to Open Reduction Internal Fixation in the Treatment of Isolated Displaced Greater Tuberosity Fractures?

BACKGROUND: Arthroscopic double-row suture-anchor fixation and open reduction and internal fixation (ORIF) are used to treat displaced greater tuberosity fractures, but there are few data that can help guide the surgeon in choosing between these approaches. QUESTIONS/PURPOSES: We therefore asked: (1) Is there a difference in surgical time between arthroscopic double-row suture anchor fixation and ORIF for isolated displaced greater tuberosity fractures? (2) Are there differences in the postoperative ROM and functional scores between arthroscopic double-row suture anchor fixation and ORIF for isolated displaced greater tuberosity fractures? (3) Are there differences in complications resulting in additional operations between the two approaches? METHODS: Between 2006 and 2012, we treated 79 patients surgically for displaced greater tuberosity fractures. Of those, 32 (41%) were considered eligible for our study based on inclusion criteria for isolated displaced greater tuberosity fractures with a displacement of at least 5 mm but less than 2 cm. During that time, we generally treated patients with displaced greater tuberosity fractures with a displacement greater than 1 cm or with a fragment size greater than 3×3 cm with open treatment, and patients with displaced greater tuberosity fractures with a displacement less than 1 cm or with a fragment size less than 3×3 cm with arthroscopic treatment. Fifty-three underwent open treatment based on those indications, and 26 underwent arthroscopic treatment, of whom 17 (32%) and 15 (58%) were available for followup at a mean of 34 months (range, 24-28 months). All patients with such fractures identified from our institutional database were treated by these two approaches and no other methods were used. Surgical time was defined as the time from initiation of the incision to the time when suture of the incision was finished, and was determined by an observer with a stopwatch. Patients were followed up in the outpatient department at 6, 12, and 24 weeks, and every 6 month thereafter. Radiographs showed optimal reduction immediately after surgery and at every followup. Radiographs were obtained to assess fracture healing. Patients were followed up for a mean of 34 months (range, 24-48 months). At the last followup, ROM, VAS score, and American Shoulder and Elbow Surgeons (ASES) score were used to evaluate clinical outcomes. All these data were retrieved from our institutional database through chart review. Complications were assessed through chart review by one observer other than the operating surgeon. RESULTS: Patients who underwent arthroscopic double-row suture anchor fixation had longer surgical times than did patients who underwent ORIF (mean, 95.3 minutes, SD, 10.6 minutes vs mean, 61.5 minutes, SD, 7.2 minutes; mean difference, 33.9 minutes; 95% CI, 27.4-40.3 minutes; p < 0.001). All patients achieved bone union within 3 months. Compared with patients who had ORIF, the patients who had arthroscopic double-row suture anchor fixation had greater ranges of forward flexion (mean, 152.7°, SD, 13.3° vs mean, 137.7°, SD, 19.2°; p = 0.017) and abduction (mean, 146.0°, SD, 16.4° vs mean, 132.4°, SD, 20.5°; p = 0.048), and higher ASES score (mean, 91.8 points, SD, 4.1 points vs mean, 87.4 points, SD, 5.8 points; p = 0.021); however, in general, these differences were small and of questionable clinical importance. With the numbers available, there were no differences in the proportion of patients experiencing complications resulting in reoperation; secondary subacromial impingement occurred in two patients in the ORIF group and postoperative stiffness in one from the ORIF group. The two patients experiencing secondary subacromial impingement underwent reoperation to remove the implant. The patient with postoperative stiffness underwent adhesion release while receiving anesthesia, to improve the function of the shoulder. These three patients had the only reoperations. CONCLUSIONS: We found that in the hands of surgeons comfortable with both approaches, there were few important differences between arthroscopic double-row suture anchor fixation and ORIF for isolated displaced greater tuberosity fractures. Future, larger studies with consistent indications should be performed to compare these treatments; our data can help inform sample-size calculations for such studies. LEVEL OF EVIDENCE: Level III, therapeutic study.

Arthroscopic Fixation of Tibial Eminence Fractures: A Clinical Comparative Study of Nonabsorbable Sutures Versus Absorbable Suture Anchors.

PURPOSE: To compare clinical outcomes of arthroscopic therapy for tibial eminence fracture with nonabsorbable suture and absorbable suture anchor. METHODS: Between February 2010 and September 2012, a total of 60 tibial eminence fracture patients were treated with nonabsorbable suture fixation or absorbable suture anchor fixation under arthroscopy. Patients with tibial plateau fractures and other significant injuries, including osteochondral lesions, meniscal tear, and anterior cruciate ligament (ACL) or mutiligament injuries, were excluded from the study. Radiographs, anterior drawer test (ADT), Lachman test, Lysholm score, and International Knee Documentation Committee (IKDC) 2000 subjective score were employed to evaluate clinical outcomes in follow-up. RESULTS: A total of 41 patients were analyzed. Among these patients, 22 were treated with nonabsorbable suture fixation and 19 with absorbable suture anchor fixation. According to the modified Meyers-McKeever classification, 15 cases were categorized as type II, 21 as type III, and 5 as type IV fractures. The mean time from injury to surgery was 7.1 days (range, 3 to 12 days). All patients were followed up for a median period of 33.7 months (range, 24 to 45 months). Radiographic evaluation showed optimal reduction immediately after operation and bone union within 3 months in all patients. At the final follow-up, there was no limitation of knee motion range in any patient. Grade II laxity was found in 2 cases from suture group and 1 from suture anchor group, showing no significant difference based on ADT (χ(2) = 0.538, P = .764) and Lachman test (χ(2) = 0.550, P = .760). Lysholm and IKDC 2000 subjective scores were significantly improved (P < .001). However, there were no significant differences in the improvement of Lysholm (t = 0.522, P = .604) and IKDC 2000 subjective scores (t = 0.644, P = .523) between the 2 groups. CONCLUSIONS: Nonabsorbable suture fixation and absorbable suture anchor fixation are equivalent techniques in terms of the clinical efficacy of arthroscopic tibial eminence fracture treatment. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

[Study on the accurate effects of radial shock wave therapy equipment].

The basic mechanical properties of a Radial Shock Wave Therapy Equipment (RSWTE) were experimentally studied in this paper. The output energy of the RSWTE working on the operation frequency of 10 Hz was measured by dynamic pressure transducer under the conditions of different operation pressure. The results showed that both operation pressure and operation frequency have effects on the output energy of the equipment. The output energy increases with the increase of operation pressure, and the magnitude of increased energy decreases with higher operation of frequency. With the increase of operation frequency, the output energy rises up in condition of lower operation pressure and drops off in condition of higher operation pressure. The accurate medical treatment should be selected with the optimized energy and condition according to the treatment requirement to different illness in clinical medical applications.

Stabilizing Mechanisms in Patients Treated Using Hill-Sachs Remplissage With Bankart Repair in Abduction-External Rotation Position.

BACKGROUND: Hill-Sachs lesion (HSL) remplissage with Bankart repair (RMBR) provides a minimally invasive solution for treating HSLs and glenoid bone defects of <25%. The infraspinatus tendon is inserted into the HSL during the remplissage process, causing the infraspinatus to shift medially, leading to an unknown effect on glenohumeral alignment during the resting abduction-external rotation (ABER) and muscle-active states. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the possible check-rein effect and muscle-active control in stabilizing the glenohumeral joint after RMBR in vivo. We hypothesized that the check-rein effect and active control would stabilize the glenohumeral joint in the ABER position in patients after RMBR. STUDY DESIGN: Controlled laboratory study. METHODS: We included 42 participants-22 patients in group A who met the inclusion criteria after RMBR and 20 healthy participants in group B without shoulder laxity. Three-dimensional magnetic resonance imaging was performed to analyze the alignment relationship of the glenohumeral joint with and without muscular activity. Ultrasonic shear wave elastography was used to evaluate the elastic properties of the anterior capsule covered with the anterior bands of the inferior glenohumeral ligament. RESULTS: Patients who underwent RMBR demonstrated more posterior (-1.81 ± 1.19 mm vs -0.76 ± 1.25 mm; P = .008) and inferior (-1.05 ± 0.62 mm vs -0.45 ± 0.48 mm; P = .001) shifts of the humeral head rotation center and less anterior capsular elasticity (70.07 ± 22.60 kPa vs 84.01 ± 14.08 kPa; P = .023) than healthy participants in the resting ABER state. More posterior (-3.17 ± 0.84 mm vs -1.81 ± 1.19 mm; P < .001) and less-inferior (-0.34 ± 0.56 mm vs -1.05 ± 0.62 mm; P < .001) shifts of the humeral head rotation center and less anterior capsular elasticity (36.57 ± 13.89 kPa vs 70.07 ± 22.60 kPa; P < .001) were observed in the operative shoulder during muscle-active ABER than in resting ABER states. CONCLUSION: The check-rein effect and muscle-active control act as stabilizing mechanisms in RMBR during the ABER position. CLINICAL RELEVANCE: Stabilizing mechanisms in RMBR during the ABER position include the check-rein effect and muscle-active control.

Proteomic analysis of synovial fluid: insight into the pathogenesis of knee osteoarthritis.

PURPOSE: We conducted a proteomic analysis of synovial fluid (SF) to identify differentially expressed proteins and analyse their correlation with osteoarthritis (OA) severity. Our primary purpose was to gain insight into the pathogenesis of OA. METHODS: SF samples were acquired from 12 knee OA patients and 12 non-OA controls (ten had a meniscus injury, two had a discoid meniscus and all exhibited intact articular cartilage) and sequentially subjected to two-dimensional electrophoresis (2-DE). The radiographic grading of knee OA was performed using the Kellgren-Lawrence criteria. Differentially expressed proteins were identified by matrix-assisted laser desorption/ionisation time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS). Proteins of interest identified from SF were detected using an enzyme-linked immunosorbent assay (ELISA). RESULTS: A total of 31 protein spots showed significant differences (p < 0.05) between the sample groups; 25 of the 31 spots (80.6 %) were identified as proteins of interest. Among them 20 corresponded to up-regulation and five to down-regulation in OA samples. HLA-DR was one of the proteins up-regulated, which was confirmed by ELISA. CONCLUSIONS: These observations have implications in delineating the protein expression underlying the pathogenesis of OA and facilitate further elucidation of molecular mechanisms involved in disease progression. Substantial alterations of the protein profile in SF may be associated with OA severity.

Gadoxetic acid-enhanced MRI combined with T1 mapping and clinical factors to predict Ki-67 expression of hepatocellular carcinoma.

Objectives: To explore the predictive value of gadoxetic acid-enhanced magnetic resonance imaging (MRI) combined with T1 mapping and clinical factors for Ki-67 expression in hepatocellular carcinoma (HCC). Methods: A retrospective study was conducted on 185 patients with pathologically confirmed solitary HCC from two institutions. All patients underwent preoperative T1 mapping on gadoxetic acid-enhanced MRI. Patients from institution I (n = 124) and institution II (n = 61) were respectively assigned to the training and validation sets. Univariable and multivariable analyses were performed to assess the correlation of clinico-radiological factors with Ki-67 labeling index (LI). Based on the significant factors, a predictive nomogram was developed and validated for Ki-67 LI. The performance of the nomogram was evaluated on the basis of its calibration, discrimination, and clinical utility. Results: Multivariable analysis showed that alpha-fetoprotein (AFP) levels > 20ng/mL, neutrophils to lymphocyte ratio > 2.25, non-smooth margin, tumor-to-liver signal intensity ratio in the hepatobiliary phase ≤ 0.6, and post-contrast T1 relaxation time > 705 msec were the independent predictors of Ki-67 LI. The nomogram based on these variables showed the best predictive performance with area under the receiver operator characteristic curve (AUROC) 0.899, area under the precision-recall curve (AUPRC) 0.946 and F1 score of 0.912; the respective values were 0.823, 0.879 and 0.857 in the validation set. The Kaplan-Meier curves illustrated that the cumulative recurrence probability at 2 years was significantly higher in patients with high Ki-67 LI than in those with low Ki-67 LI (39.6% [53/134] vs. 19.6% [10/51], p = 0.011). Conclusions: Gadoxetic acid-enhanced MRI combined with T1 mapping and several clinical factors can preoperatively predict Ki-67 LI with high accuracy, and thus enable risk stratification and personalized treatment of HCC patients.

[Study on the evaluation of glenoid bone defects by MRI three-dimensional reconstruction].

Objective: To investigate the feasibility of MRI three-dimensional (3D) reconstruction model in quantifying glenoid bone defect by comparing with CT 3D reconstruction model measurement. Methods: Forty patients with shoulder anterior dislocation who met the selection criteria between December 2021 and December 2022 were admitted as study participants. There were 34 males and 6 females with an average age of 24.8 years (range, 19-32 years). The injury caused by sports injury in 29 cases and collision injury in 6 cases, and 5 cases had no obvious inducement. The time from injury to admission ranged from 4 to 72 months (mean, 28.5 months). CT and MRI were performed on the patients' shoulder joints, and a semi-automatic segmentation of the images was done with 3D slicer software to construct a glenoid model. The length of the glenoid bone defect was measured on the models by 2 physicians. The intra-group correlation coefficient ( ICC) was used to evaluate the consistency between the 2 physicians, and Bland-Altman plots were constructed to evaluate the consistency between the 2 methods. Results: The length of the glenoid bone defects measured on MRI 3D reconstruction model was (3.83±1.36) mm/4.00 (0.58, 6.13) mm for physician 1 and (3.91±1.20) mm/3.86 (1.39, 5.96) mm for physician 2. The length of the glenoid bone defects measured on CT 3D reconstruction model was (3.81±1.38) mm/3.80 (0.60, 6.02) mm for physician 1 and (3.99±1.19) mm/4.00 (1.68, 6.38) mm for physician 2. ICC and Bland-Altman plot analysis showed good consistency. The ICC between the 2 physicians based on MRI and CT 3D reconstruction model measurements were 0.73 [95% CI (0.54, 0.85)] and 0.80 [95% CI (0.65, 0.89)], respectively. The 95% CI of the difference between the two measurements of physicians 1 and 2 were (-0.46, 0.49) and (-0.68, 0.53), respectively. Conclusion: The measurement of glenoid bone defect based on MRI 3D reconstruction model is consistent with that based on CT 3D reconstruction model. MRI can be used instead of CT to measure glenoid bone defects in clinic, and the soft tissue of shoulder joint can be observed comprehensively while reducing radiation.

In vitro sustained release of recombinant human bone morphogenetic protein-2 microspheres embedded in thermosensitive hydrogels.

Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a critical regulator of osteogenic capacity that is commonly used in bone grafts. The effectiveness of rhBMP-2 may be reduced as it can become unstable and degraded after injection into the body. Microspheres are considered appropriate vehicles for the sustained release of proteins in vivo. In this study, rhBMP-2 microspheres were manufactured using the water-in-oil-in-water (W/O/W) double-emulsion solvent-extraction technique by encapsulation in poly(lactic-co-glycolic) acid (PLGA). The microspheres were then embedded in two hydrogels made of either poloxamer 407 hydrogel or chitosan thioglycolic acid (CS-TA). The encapsulation efficiency and in vitro release of rhBMP-2 were examined and compared with the control release system (rhBMP-2 microspheres alone). The rhBMP-2 microspheres in the CS-TA hydrogel showed the lowest burst release (about 40% in the first 8h) among the three groups. The mechanisms may be the high viscosity of CS-TA hydrogel and the sustained release characteristics of CS-TA itself. The CS-TA hydrogel combined with PLGA microspheres can efficiently encapsulate rhBMP-2, control the burst release at early time points, and provide sustained release in vitro. It may be an appropriate rhBMP-2 vehicle for bone regeneration.

Optimization of the Platelet-Rich Plasma Concentration for Mesenchymal Stem Cell Applications.

IMPACT STATEMENT: In the current study, we screened the effects of different concentrations of platelet-rich plasma (PRP) on the mesenchymal stem cell (MSC) proliferation and differentiation. Our data demonstrated that concentrated PRP exerted different effects on cell proliferation and on the osteogenic, adipogenic, and chondrogenic differentiation of human bone marrow-derived MSCs. Meanwhile, we optimized PRP concentrations for each of these lineage differentiation and MSC expansion and, thus, suggested several promising clinical strategies for different kinds of diseases. These findings may help explain the controversial effects of PRP on MSCs and improve the progress in precise applications of PRP-based regenerative strategies.

Proteomic analysis of synovial fluid in osteoarthritis using SWATH­mass spectrometry.

The lack of early diagnostic maneuvers and effective pharmacotherapy for osteoarthritis (OA) is predominantly attributed to current limited understanding of its pathogenesis. In the present study, the alteration of synovial fluid (SF) proteome in OA were analyzed using SWATH­mass spectrometry (SWATH­MS) to further elucidate the pathogenesis of OA. SF samples were collected from 10 OA and 10 rheumatoid arthritis (RA) patients undergoing arthroplasty and 10 patients undergoing arthroscopy for traumatic arthritis (meniscus injury without cartilage lesion). According to the Kellgren­Lawrence (KL) radiographic grading criteria, all the OA and RA patients were classified as KL grade 4. SWATH­MS was applied to identify differentially expressed proteins specifically regulated in OA. Differentially expressed proteins identified by SWATH­MS were subjected to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation. Proteins of interest were quantified by enzyme­linked immunosorbent assay (ELISA) following identification. With the use of SWATH­MS, 131 proteins were identified to be differentially expressed in OA, of which 93 corresponded to upregulation and 38 to downregulation. Complement C1r was the most significantly upregulated protein in OA. Twenty­eight out of the 131 proteins were specifically regulated in OA, of which 17 were upregulated and 11 were downregulated. Dickkopf­related protein 2 (DKK2) was one of the proteins specifically upregulated in OA. Furthermore, KEGG pathway annotation indicated that differentially expressed proteins in OA were enriched in complement and coagulation cascades. ELISA indicated that OA severity was positively correlated with the levels of complement C1r (r=0.549; P<0.001) and DKK2 (r=0.79; P<0.001) in the SF. The results indicate that complement and coagulation cascades are involved in the pathogenesis of OA. Differentially expressed proteins, including complement C1r and DKK2 may be used as potential biomarkers or drug targets, which may facilitate with intervention of OA.

[Clinical research on suture anchor fixation for the treatment of avulsion fracture of tibial intercondylar eminence under arthroscopy].

OBJECTIVE: To evaluate the early clinical effects of suture anchor fixation for the treatment of avulsion fracture of tibial intercondylar eminence under arthroscopy. METHODS: From July 2012 to January 2015, 22 patients with the avulsion fracture of tibial intercondylar eminence were treated with arthroscopic suture anchor fixation. There were 12 males and 10 females, with an average age of 22.8 years old(ranged, 18 to 33 years old). Nine patients had the fractures in the right knee and 13 patients had the fractures in the left knee. The mean duration from injury to surgery was 6.8 days(ranged, 3 to 11 days). According to the improved Meyers-McKeever classification, 13 cases were type II, 7 cases were type III, and 2 cases were type IV. The clinical outcomes were evaluated by the range of motion, the Lysholm score, the IKDC 2000 subjective knee score, the axial shift test, and the anterior drawer test. RESULTS: All the incisions healed by first intention, and no complications occurred. All the patients were followed up, and the mean duration was 32.8 months (ranged, 18 to 42 months). The knee range of motion was improved from preoperative (49.37±7.69) ° to (126.38±5.58) °at the latest follow-up(P<0.01). Lysholm score was improved from preoperative 43.4±5.6 to 79.2±6.2 at the latest follow-up(P<0.01). And the IKDC 2000 score was improved from preoperative 52.6±6.2 to 81.4±5.7 at the latest follow-up(P<0.01). At the latest follow-up, the patient underwent physical examination. One patient had a positive result of axial shift test at the 18th month after operation with grade II laxity of anterior cruciate ligament. One patient had a weakly positive result of anterior drawer test at the 24th month after operation. CONCLUSIONS: Absorbable suture anchor fixation for the treatment of avulsion fracture of tibial intercondylar eminence under arthroscopy can provide accurate reduction and stable fixation, which can be applied to treat all types of fractures including comminuted fracture, and it is not necessary to remove the implant in the second operation.

[Clinical research of treating the avulsed fracture of humerus greater tuberosity using an arthroscopic double-row suture anchor fixation technique].

OBJECTIVE: To evaluate the early clinical effects of treating the avulsed fracture of humerus greater tuberosity using the double-row suture anchor fixation technique. METHODS: Total 20 patients with the avulsed fracture of the greater tuberosity of the humerus were treated from September 2009 to January 2013. There were 12 males and 7 females, with an average age of 46.8 years old(24 to 69 years old). Eleven patients had injuries on right shoulder joint and 8 patients had injuries on left side. The injury mechanism included 10 cases of traffic accident, 6 cases of sports injury, and 3 cases of falls. The mean interval from injury to surgery was 34.9 d (ranged, 3 to 72 d). The affacted arm was suspended and fixed within 3 weeks after operation. The swing exercise of shoulder joint was performed from the 2nd day after operation. The strap was removed 3 weeks after operation, and painless active exercise was performed 6 weeks after operation. The patients were followed up in the outpatient department 6, 12 and 24 weeks after operation, and then every 6 months. AP and lateral X-ray films were taken at each follow-up time. At the latest follow-up, protractor was used to measure activity of patients; and VAS pain score, California University of Losangeles(UCLA) standard, American Shoulder and Elbow Surgeons (ASES) score were used to evaluate therapeutic effects. RESULTS: All the patients were followed up, with a mean duration of 35.2 months (ranged, 24 to 48 months). All the incisions were healed on the first stage without secondary acromion impingement and other complications. All the patients had bony union within 12 weeks. The movements of shoulder joints including flexion, abduction, external rotation, internal rotation were increased obviously(P<0.05). The UCLA score was increased from preoperative 15.2±5.3 to 35.6±6.1 at the latest follow-up. The ASES score was increased from preoperative 31.2±5.4 to 91.2±6.8 at the latest follow-up (P<0.05). CONCLUSIONS: It has satisfactory curative effects for the avulsed fracture of humerus greater tuberosity using the double-row suture anchor fixation technique, especially the cases of small or comminuted fractures. It has several advantages such as firm fixation, simple and secure operation as well as quick postoperative recovery. Finally, patient should take exercises actively after operations.