Betaine alleviates alcohol-induced osteonecrosis of the femoral head via mTOR signaling pathway regulation

Osteonecrosis of the femoral head (ONFH) is usually caused by chronic and excessive alcohol dependency, and this condition largely suppresses the osteogenic differentiation of bone mesenchymal stem cells (BMSCs). As a trimethyl derivative of glycine, betaine is an important human nutrient that regulates a series of vital biological processes, including oxidative stress, inflammatory responses, osteoblast differentiation and cellular apoptosis. However, no study has investigated the role of betaine in alcohol-induced ONFH. In this study, we hypothesized that betaine might have protective effects on ethanol-treated BMSCs and decrease the morbidity of alcohol-induced ONFH in a rat model. In vitro, we found that ethanol significantly downregulated the expression of osteocalcin (OCN), collagen 1 (COL1) and RUNX2 via activating the mammalian target of rapamycin (mTOR) signaling cascade. However, the inhibitory effects were rescued by betaine co-treatment at concentrations of 1 mM and 10 mM. In vivo, the typical ONFH pathological changes in a rat model of alcohol-induced ONFH were investigated by using multiple methods, including hematoxylin-eosin staining, micro-CT scans, TdT-mediated dUTP nick end labeling (TUNEL) assays and immunohistochemical staining for OCN and COL1. Osteonecrotic lesions of the femoral head could be alleviated by betaine as evidenced by significant histological and radiological improvements. Collectively, betaine plays a protective role against ethanol-induced suppression of osteogenesis and mineralization of hBMSCs and is thus a potential pharmacotherapy for alcohol-induced ONFH in vivo.

Autologous costal chondral transplantation and costa-derived chondrocyte implantation: emerging surgical techniques

It is a great challenge to cure symptomatic lesions and considerable defects of hyaline cartilage due to its complex structure and poor self-repair capacity. If left untreated, unmatured degeneration will cause significant complications. Surgical intervention to repair cartilage may prevent progressive joint degeneration. A series of surgical techniques, including biological augmentation, microfracture and bone marrow stimulation, autologous chondrocyte implantation (ACI), and allogenic and autogenic chondral/osteochondral transplantation, have been used for various indications. However, the limited repairing capacity and the potential pitfalls of these techniques cannot be ignored. Increasing evidence has shown promising outcomes from ACI and cartilage transplantation. Nevertheless, the morbidity of autologous donor sites and limited resource of allogeneic bone have considerably restricted the wide application of these surgical techniques. Costal cartilage, which preserves permanent chondrocytes and the natural osteochondral junction, is an ideal candidate for the restoration of cartilage defects. Several in vitro and in vivo studies have shown good performance of costal cartilage transplantation. Although costal cartilage is a classic donor in plastic and cosmetic surgery, it is rarely used in skeletal cartilage restoration. In this review, we introduce the fundamental properties of costal cartilage and summarize costa-derived chondrocyte implantation and costal chondral/osteochondral transplantation. We will also discuss the pitfalls and pearls of costal cartilage transplantation. Costal chondral/osteochondral transplantation and costa-based chondrocytotherapy might be up-and-coming surgical techniques for recalcitrant cartilage lesions.

LMCD1 promotes osteogenic differentiation of human bone marrow stem cells by regulating BMP signaling

Human bone marrow stem cells (BMSCs) are heterogeneous progenitor cells with two defining features, self-renew and multi-lineage differentiation. As one of the differentiation directions, osteogenesis is vital for bone homeostasis. A growing body of evidences show that ubiquitin-dependent protein degradation plays an essential role in the osteogenic differentiation of BMSCs. In this study, we found that LMCD1 was upregulated during osteogenic differentiation process of BMSCs by analyzing GSE80614. In vitro and in vivo functional studies confirmed that LMCD1 was critical to the osteogenic commitment of BMSCs. Compared to those of the controls, downregulation of LMCD1 significantly restrained osteogenic differentiation and enhanced adipogenic differentiation, while upregulation of LMCD1 increased the osteogenic differentiation and suppressed adipogenic differentiation. Mechanically, we found that LMCD1 could protect RUNX2 and Smad1 protein from Smurf1-induced ubiquitination degradation thereby regulating BMP signaling. In conclusion, our findings suggest that LMCD1 is a novel regulator of osteogenic differentiation and may be a potential therapeutic target for bone metabolism related diseases.

Efficacy of acetaminophen with and without oxycodone for analgesia in non-operative treatment of extremity fractures in adults: protocol for a double-blind randomized clinical trial

BACKGROUND

Opioids and acetaminophen are both widely used to relieve pain after non-operative treatment of limb fractures, but evidence for the superiority of opioids versus acetaminophen is lacking. In this study, we aim to determine whether acetaminophen is non-inferior to the acetaminophen/oxycodone combination for pain relief after non-operative fixation of an extremity limb fracture. We hypothesize that acetaminophen is non-inferior to the acetaminophen/oxycodone combination.

METHODS

A double-blind randomized controlled trial will be conducted. Power analysis determined that 1226 participants will be needed (P <0.05, power 90%). Patients with acute limb fracture who receive non-operative treatment will be recruited and randomly allocated into two groups: the intervention group will receive oral oxycodone (10 mg) and acetaminophen (650 mg), and the control group will receive acetaminophen (650 mg) only. All participants will be instructed to take one pill of study medication on an as-needed basis and no more frequently than once every 8 h. The primary outcome measure will be scores on the 11-point Numeric Rating Scale (NRS-11) over 14 days. Secondary outcome measures are scores on the Self-Rating Anxiety Scale (SAS), Self-Rating Depression Scale (SDS), EuroQol five-dimension questionnaire (EQ-5D), self-rated satisfaction with the analgesia produced, self-reported nighttime sleep duration, number of intervention or control pills used, and total duration for taking intervention or control medication. Change of pain scores and the number of times that analgesic drugs were taken in the two groups will be statistically evaluated with Student t tests according to their fracture site.

DISCUSSION

This study will be a randomized controlled trial that is adequately powered to test the hypothesis that acetaminophen is non-inferior to the combination of acetaminophen and oxycodone in relieving objectively measured pain after non-operative treatment of limb fractures in adults. It will hopefully provide a safe and effective analgesic plan for such patients.

TRIAL REGISTRATION

ChiCTR registry: ChiCTR1800017015 . Registered on July 8, 2018.

Current surgical options and innovation for repairing articular cartilage defects in the femoral head

Total hip arthroplasty is a common surgical technique, yet it has severe complications, such as loosening and repeated revision. Thus, hip-preserving surgical options should be considered first to treat cartilage defects in the femoral head, especially for younger patients. Current surgical options for chondral repair of the femoral head include microfracture, trapdoor procedure, transplantation of osteochondral allografts and autografts, and autologous chondrocyte implantation. Each of these techniques has unique advantages and limitations; however, none of them have been consented as the best practice for cartilage defects. In this review article, we also introduced a novel technique for repairing osteochondral defects of the femoral head using autologous costal cartilage grafts that may have good translational potential for cost-effective and safe applications.

The translational potential of this article

This review updates current surgical options for reparing articular cartilage defects in the femoral head. We also introduce a novel technique for repairing osteochondral defects of the femoral head using autologous costal cartilage grafts.

Vascularized Fibular Grafting in Treatment of Femoral Neck Nonunion: A Prognostic Study Based on Long-Term Outcomes

BACKGROUND

The purpose of this study was to evaluate the long-term efficacy and prognostic factors predicting success of revision surgery with free vascularized fibular grafting (FVFG) for treatment of femoral neck nonunion.

METHODS

We prospectively enrolled patients who underwent revision surgery with FVFG between January 2001 and January 2013 in a tertiary hospital in China. A total of 98 patients with a minimum 5-year follow-up were included for analysis. The criteria for FVFG failure were conversion to hip arthroplasty, recommendation for a hip arthroplasty, or a Harris hip score of <80 points. Demographic information, the preoperative neck shortening ratio (NSR), the fixation method, and postoperative radiographic parameters including the postoperative NSR and neck-shaft angle (NSA) were recorded for prognostic analysis.

RESULTS

At an average of 9.8 ± 3.5 years (range, 3 to 17 years) postoperatively, the overall success rate of this surgical procedure was 77% (75 of 98). The success and failure groups had no significant differences in age, fixation method, interval between initial fixation and revision surgery, or postoperative NSA. The success group had a significantly higher NSR than the failure group both preoperatively (77.8% versus 62.4%, p < 0.001) and postoperatively (87.6% versus 78.4%, p = 0.001). The receiver operating characteristic (ROC) curve analysis revealed an optimal cutoff for preoperative NSR of 60% to predict the outcome. Patients with a preoperative NSR of >60% had a success rate of 91% (68 of 75).

CONCLUSIONS

Revision surgery with FVFG and internal fixation is an effective and important option for treating nonunion of the femoral neck in young patients without severe preoperative shortening and neck resorption (preoperative NSR of >60%).

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Replantation of a Completely Amputated Thumb with Assistance of High-Speed Video Recording

Background

Generally, surgeons assess the quality of vascular anastomosis in digit replantation on the basis of their experience.

Description

The steps for replantation of a completely amputated thumb, with assistance of high-speed video recording, consist of (1) debridement, (2) fixation, (3) tendon suture, (4) anastomosis, and (5) wound closure^1,2.

Alternatives

Revision amputation or flap coverage.

Rationale

With the assistance of high-speed video recording, the refilling velocity ratio (RVR) is an objective index for the quality assessment of the vascular anastomosis.

Ginkgolide B promotes osteoblast differentiation via activation of canonical Wnt signalling and alleviates osteoporosis through a bone anabolic way

Osteoporosis has become a worldwide problem as the population ages. Although many advances have been made in the treatment of osteoporosis in the past few years, the outcome are sometimes disturbing because of the adverse effects of these treatments. Further studies are still needed to identify novel alternate agents to improve the therapeutic effect. Ginkgolide B (GB), a derivative of Ginkgo biloba leaves, has numerous pharmacological effects, including anticancer and anti-inflammation activities. However, the effect of GB on the regulation of osteoblast activity and bone formation effect has not yet been investigated. In this study, we showed the in vitro and in vivo effects of GB on osteoblast differentiation and bone formation. We found that GB promotes osteoblast differentiation of Bone Mesenchymal Stem Cells (BMSCs) and MC3T3-E1 cells in vitro in a Wnt/β-catenin-dependent manner. In an in vivo study, we constructed a cranial defect model in rats and treated with GB. Histomorphometric and histological analyses confirmed that the usage of GB significantly promotes bone formation. Further study on ovariectomy (OVX) rats demonstrated that GB is capable of alleviating ovariectomy-induced bone loss by enhancing osteoblast activity. Our findings indicate that GB is a potential therapeutic agent of osteoporosis through an anabolic way in bone.

Ischaemic stroke etiological classification system: the agreement analysis of CISS, SPARKLE and TOAST

Background and purpose

The ideal stroke classification system needs to have validity, high reliability and applicability among different stroke research settings. The Chinese Ischemic Stroke Subclassification (CISS) and the Subtypes of Ischemic Stroke Classification System (SPARKLE) have emerged recently but have not been tested using agreement analysis. As a result, the objective of this study is to investigate the level of agreement among stroke subtype classifications using CISS, SPARKLE and Trial of Org 10172 in Acute Stroke Treatment (TOAST). We also analyse the inter-rater reliability of CISS.

Methods

The data include 623 inpatients who have had an ischaemic stroke, accrued from Beijing Tiantan Hospital between 1 October 2015 and 19 April 2016. According to the diagnostic standards of the three subtype classification systems, 299 inpatients who satisfied the requirements of our study were independently classified with etiological subtypes, and we compared the three subclassifications.

Results

There was substantial overall agreement among the three classification systems: CISS versus SPARKLE (kappa value=0.684, p<0.001), CISS versus TOAST (kappa value=0.615, p<0.001) and SPARKLE versus TOAST (kappa value=0.675, p<0.001). The inter-rater reliability of CISS was excellent (kappa value=0.857, p<0.001). Furthermore, among the three subtype classification systems, the variance analysis results of the etiological subtypes were not uniform.

Conclusion

There were generally substantial agreements among three ischaemic stroke etiological classification systems. CISS is a valid and reliable classification system, with which different stroke research centres can apply and compare data.

Molecular Detection of QoI Resistance in Colletotrichum gloeosporioides Causing Strawberry Anthracnose Based on Loop-Mediated Isothermal Amplification Assay

Anthracnose is one of the most common diseases in strawberry plants. Colletotrichum gloeosporioides is the major cause of anthracnose in China, including Zhejiang Province. Early, specific, reliable, and time-saving detection is urgently needed to prevent the further spread of C. gloeosporioides, guiding farmers to utilize chemicals to control anthracnose. In this study, we showed that the high resistance to pyraclostrobin, caused by a point mutation at codon 143 (GGT→GCT) in the cytochrome b gene of C. gloeosporioides was prevalent in the strawberry growing regions, and we developed a loop-mediated isothermal amplification (LAMP) assay as a detection method. Primer sets S0 and S4 could be used to specifically detect C. gloeosporioides isolates and the G143A mutations, respectively. A detection limit of 10^-2 ng (10 pg), which is at least 10-fold more sensitive than conventional polymerase chain reaction, was achieved by the LAMP assay. Here, we utilized lateral-flow devices (LFDs), nitrocellulose membranes that can absorb nucleic acids, to acquire the total genomic DNA of strawberry plants within 2 min. The LFD membranes were used as DNA templates for the LAMP assays to accurately detect strawberry plants infected with C. gloeosporioides. This diagnostic method for strawberry anthracnose was accomplished within 1 h, including the sample preparation and LAMP assays. Collectively, we developed a sensitive and practical method for monitoring C. gloeosporioides and its quinone outside inhibitor-resistant mutants. The LAMP assay for detection of C. gloeosporioides in strawberry plants has great potential for rapid strawberry anthracnose surveillance and will provide farmers with advice on preventing C gloeosporioides at the early stages of strawberry development.

A Dynamic Model for Predicting Outcome in Patients with HBV Related Acute-On-Chronic Liver Failure

INTRODUCTION AND AIM

Accurately predicting the prognosis of individual patient is crucial in the management of ACLF. We aimed to establish a specific prognostic model for HBV-related ACLF patients treated with nucleoside analog (NA).

MATERIAL AND METHODS

We prospectively collected 205 ACLF cases diagnosed according to the APASL criteria. A dynamic prognostic model based on APASL criteria was established and validated. To demonstrate that the model is also applicable to those within EASL criteria, we divided the patients into two groups: met APASL criteria only (group A, n = 123); met both APASL and EASL criteria (group B, n = 82). Its prognostic accuracy was also compared with chronic liver failure-sequential organ failure assessment (CLIF-SOFA) score in group B.

RESULTS

The model is: R = 0.94 x Bilirubin + 0.53 x evolution of Bilirubin - 0.45 x PT-A - 0.22 x evolution in PT-A -0.1 x PLT + 10 x anti-HBe. The area under receiver operating characteristic curve (AUC) of the model for predicting 90-day mortality was 0.86, which was significantly higher than that of model for end stage liver disease(MELD), MELD-Na, CLIF-SOFA, ΔMELD (7d) and ΔMELD-Na (7d), ΔCLIF- SOFA(7d) (all p &lt; 0.01). The AUC of our model in the validation group was 0.79 which was superior to MELD (0.45) CLIF-SOFA (0.53) score in group B patients (p &lt; 0.01).

CONCLUSION

In conclusion, the model was superior to the conventional methods in predicting the outcomes of patients with HBV related ACLF treated with NA. It is the first description of a novel prognostic model using consecutive data in patients with HBV-induced acute-on-chronic liver failure (ACLF) treated by nucleoside analogs.

Two-Incision, Wire-Assisted Achilles Tendon Z-Lengthening: Surgical Technique and Case Report

Achilles tendon lengthening is an important surgical procedure to manage gastrocnemius-soleus complex contracture. Because the Achilles tendon fibers twist like Manila rope and torsion varies widely, it is very difficult for any current lengthening procedure to be performed that accurately follows the rotation of the fibers; thus, irregular sliding or repeated cutting of the fibers may result. We present a patient with Achilles tendon contracture in whom the tendon was divided coronally along the twisted fibers using a stainless-steel wire before hemisection for Z-lengthening; thus, hemisection could be performed not only with minimal invasion but also accurately. After tendon lengthening, ankle function was restored to near normal. After a 15-month follow-up time, improvement of ankle function was well maintained, and no complication, such as crouch gait, was observed. We believe this was owed to accurate division of the tendon fibers before lengthening, preservation of the paratenon and deep fascial tube, and the use of Z-lengthening.

[Mid-term effectiveness of surgical hip dislocation for femoroacetabular impingement]

Objective

To assess the mid-term effecitveness of femoroacetabular impingement (FAI) treated by surgical hip dislocation.

Methods

Between April 2014 and August 2015, 15 patients (16 hips) with FAI were enrolled in the study and treated with surgical hip dislocation. There were 12 males and 3 females with an average age of 36.6 years (range, 22-59 years). Among them, 14 cases involved in unilateral hip and 1 in bilateral hips. The mean disease duration was 28 months (range, 4-120 months). Preoperative visual analogue scale (VAS) score and Harris hip score were 7.9±1.0 and 44.1±9.3, respectively.

Results

All incisions healed by first intention. There was no main complication, such as vessel and nerve injuries and infection. All 15 patients were followed up 30-46 months (mean, 39.5 months). The VAS score was 2.5±1.6 at 3 months and 0.5±0.7 at last follow-up. The Harris score was 85.5±4.4 at 3 months and 95.6±3.9 at last follow-up. There were significant differences in two scores between pre- and post-operation and between 3 months and last follow-up ( P<0.05). The satisfaction rate of hip function was 93.8% (15/16) at last follow-up. X-ray examination showed that there was no sign of impingment at the femoral head and neck and acetabulum forming site of the affected hip joint, and no complication such as loosening of internal fixator, nonunion of osteotomy, avascular necrosis of femoral head, and heterotopic ossification occurred during follow-up.

Conclusion

The surgical hip dislocation is a safe and effective way to treat FAI in the mid-term follow-up, which can repair torn labrum and trim acetabulum and femoral neck.

Infant Brain Development Prediction With Latent Partial Multi-View Representation Learning

The early postnatal period witnesses rapid and dynamic brain development. However, the relationship between brain anatomical structure and cognitive ability is still unknown. Currently, there is no explicit model to characterize this relationship in the literature. In this paper, we explore this relationship by investigating the mapping between morphological features of the cerebral cortex and cognitive scores. To this end, we introduce a multi-view multi-task learning approach to intuitively explore complementary information from different time-points and handle the missing data issue in longitudinal studies simultaneously. Accordingly, we establish a novel model, latent partial multi-view representation learning. Our approach regards data from different time-points as different views and constructs a latent representation to capture the complementary information from incomplete time-points. The latent representation explores the complementarity across different time-points and improves the accuracy of prediction. The minimization problem is solved by the alternating direction method of multipliers. Experimental results on both synthetic and real data validate the effectiveness of our proposed algorithm.

Cellular Response to 3-D Printed Bioactive Silicate and Borosilicate Glass Scaffolds

The repair and regeneration of loaded segmental bone defects is a challenge for both materials and biomedical science communities. Our recent work demonstrated the capability of bioactive glass in supporting bone healing and defect bridging using a rabbit femur segmental defect model without growth factors or bone marrow stromal cells (BMSCs). Here in the current work, a comprehensive in vitro evaluation of bioactive silicate (13-93) and borosilicate (2B6Sr) glass scaffolds was conducted to provide further understanding of their biological performances and to establish a correlation between in vitro and in vivo behaviors. Our in vitro evaluation using a murine MC3T3-E1 cell line confirmed the capability of both scaffolds to support cell attachment, vascular endothelial growth factor (VEGF) formation, and to stimulate mineral deposition and osteoblast marker gene expression. In particular, borosilicate (2B6Sr) glass showed a better capability in supporting the mineralization and gene expression than silicate (13-93) glass, consistent with a faster bone healing ability in vivo. The current in vitro results, combined with our previous in vivo findings, provide a strong basis for the further translational evaluation of bioactive glass scaffolds and for potential preclinical practice. © 2018 Wiley Periodicals, Inc. J. Biomed. Mater. Res. Part B, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 818-824, 2019.

[Comparison of combined intravenous and topical use of tranexamic acid with different dosage in primary total knee arthroplasty]

Objective

To compare the efficacy and safety of intra-articular combined with intravenous administration of tranexamic acid (TXA) with different dosage for reducing blood loss in primary total knee arthroplasty (TKA).

Methods

Between January 2017 and June 2017, 90 patients suffering from unilateral osteoarthritis who underwent primary TKA were randomly scheduled to three interventions, named groups A, B, and C. Single dosage of TXA via intravenous injection (IV) and different dosages of TXA via intra-articular injection (IA) were utilized in three groups, respectively. All patients in three groups received 1 g TXA IV at 10 minutes preoperatively, and received 1, 2, and 3 g TXA IA diluted in 50 mL saline after wound closure in groups A, B and C, respectively. The age, gender, body mass index, affected side of the knee, grade of osteoarthritis, grade of America Society of Anesthesiologist, preoperative hemoglobin (Hb) concentration, platelet count, preoperative prothrombin time, and activated partial thromboplastin time were not significantly different between groups ( P>0.05). The postoperative wound blood drainage, Hb concentration at 1, 3, and 7 days after operation, transfusion rate, and thromboembolic complications were observed. All patients were routinely observed for deep vein thrombosis (DVT) by the color Doppler ultrasonography at 1 week, 1 month, and 3 months after operation, and the symptomatic pulmonary embolism (PE) were observed.

Results

All patients in three groups were followed up 7-12 months (mean, 8.4 months). There was no significant difference in operation time between groups ( P>0.05). The postoperative wound blood drainage was significantly less in groups B and C than that in group A ( P<0.05), whereas no significant difference was found between group B and group C ( P>0.05). Incision skin necrosis occurred in 1 case of group B and fat liquefaction occurred in 1 case of group C. The other incisions of 3 groups healed by first intention. There was no significant difference in incision complication incidence between groups. The Hb concentration was significantly higher in groups B and C than that in group A at 1, 3, and 7 days after operation ( P<0.05). While between group B and group C, the significant difference of Hb concentration only existed at 1 day after operation ( P<0.05). The number of patients who got blood transfusion was significantly less in group B (4 cases, 13.3%) and group C (5 cases, 16.7%) than that in group A (9 cases, 30%) ( P< 0.05), but no significant difference was found between group B and group C ( P>0.05). The result of color Doppler ultrasonography showed that 1 case got DVT in the contralateral calf at 3 weeks in group B. And there was no symptomatic PE in 3 groups.

Conclusion

Combined administration of IV and IA TXA in a clinically relevant reduction in blood loss was effective and safe in primary TKA, and no thromboembolic complication was observed. The combination of 1 g IV with 2 g IA could be the optional choice.

[Research progress on the role of extracellular vesicles in bacterial pathogenesis]

Objective

To summarize the bioactive substances contained in bacterial extracellular vesicles (EVs) and their mechanisms in mediating bacterial-bacterial and bacterial-host interactions, as well as their mechanisms for use in implant infection-associated clinical guidance.

Methods

A wide range of publications on bacterial-derived EVs were extensively reviewed, analyzed, and summarized.

Results

Both gram-negative bacteria (G ^- bacteria) and gram-positive bacteria (G ⁺ bacteria) can secrete EVs which contain a variety of bioactive substances, including proteins, lipids, nucleic acids, and virulence factors, and mediate bacterial-bacterial and bacterial-host interactions. EVs play an important role in the pathogenic mechanism of bacteria.

Conclusion

Bioactive substances contained within bacteria-derived EVs play an important role in the pathogenesis of bacterial infectious diseases. In-depth study and understanding of their pathogenic mechanisms can provide new insights which will improve early clinical diagnosis, prevention, and treatment of implant-associated infection. However, at present, research in this area is still in its infancy, and many more in-depth mechanisms need to be further studied.

CENPE expression is associated with its DNA methylation status in esophageal adenocarcinoma and independently predicts unfavorable overall survival

Centrosome-associated protein E (CENPE) is a plus end-directed kinetochore motor protein, which plays a critical role in mitosis. In this in silico study, using data from the Cancer Genome Atlas-Esophageal Carcinoma (TCGA-ESCA), we analyzed the expression profile of CENPE mRNA in esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EA), its independent prognostic value and the potential mechanisms of its dysregulation in EA. Results showed that both ESCC and EA tissues had significantly elevated CENPE expression compared with their respective adjacent normal tissues. However, Kaplan-Meier survival curves showed that high CENPE was associated with unfavorable OS in EA. Univariate and multivariate analysis confirmed that CENPE expression was an independent indicator of unfavorable OS in EA patients, as a continuous variable (HR: 1.861, 95%CI: 1.235–2.806, p = 0.003) or as categorical variables (HR: 2.550, 95%CI: 1.294–5.025, p = 0.007). However, CENPE expression had no prognostic value in ESCC. Compared with the methylation status in normal samples, 3 CpG sites were hypomethylated (cg27388036, cg27443373, and cg24651824) in EA, among which two sites (cg27443373 and cg24651824) showed moderately negative correlation with CENPE expression. In addition, we also found that although heterozygous loss (-1) was frequent in EA (50/88, 56.8%), it was not necessarily associated with decreased CENPE expression compared with the copy neutral (0) cases. The methylation of the -1 group was significantly lower than that of the +1/0 group (p = 0.04). Based on these findings, we infer that CENPE upregulation in EA might serve as a valuable indicator of unfavorable OS. The methylation status of cg27443373 and cg24651824 might play a critical role in modulating CENPE expression.

Microporous polysaccharide multilayer coated BCP composite scaffolds with immobilised calcitriol promote osteoporotic bone regeneration both in vitro and in vivo

Incorporating a biomimetic coating and integrating osteoinductive biomolecules into basic bone substitutes are two common strategies to improve osteogenic capabilities in bone tissue engineering. Currently, the underlying mechanism of osteoporosis (OP)-related deficiency of osteogenesis remains unclear, and few treatments target at OP-related bone regeneration. Herein, we describe a self-assembling polyelectrolyte multilayered (PEM) film coating with local immobilisation of calcitriol (Cal) in biphasic calcium phosphate (BCP) scaffolds to promote osteoporotic bone regeneration by targeting the calcium sensing receptor (CaSR).

Methods: The ovariectomy-induced functional changes in bone marrow mesenchymal stem cells (BMSCs), protective effects of Cal, and the potential mechanism were all verified. A PEM film composed of hyaluronic acid (HA) and chitosan (Chi) was prepared through layer-by-layer self-assembly. The morphology, growth behaviour, and drug retention capability of the composite scaffolds were characterised, and their biocompatibility and therapeutic efficacy for bone regeneration were systematically explored in vitro and in vivo.

Results: The osteogenic differentiation, adhesion, and proliferation abilities of ovariectomised rat BMSCs (OVX-rBMSCs) decreased, in accordance with the deficiency of CaSR. Cal effectively activated osteogenesis in these OVX-rBMSCs by binding specifically to the active pocket of the CaSR structure, while the biomimetic PEM coating augmented OVX-rBMSCs proliferation and adhesion due to its porous surface structure. The PEM-coated scaffolds showed advantages in Cal loading and retention, especially at lower drug concentrations. HA/Chi PEM synergised with Cal to improve the proliferation, adhesion, and osteogenesis of OVX-rBMSCs and promote bone regeneration and BCP degradation in the critical-size calvarial bone defect model of OVX rats.

Conclusion: A composite scaffold based on BCP, created by simply combining a biomimetic PEM coating and Cal immobilisation, could be clinically useful and has marked advantages as a targeted, off-the-shelf, cell-free treatment option for osteoporotic bone regeneration.

Where should Kirschner wires be placed when fixing patella fracture with modified tension-band wiring? A finite element analysis

BACKGROUND

The position of Kirschner wires (K-wires) has an influence on the outcome of modified tension-band wiring (MTBW) in fixing patella fractures. However, the instruction for K-wires positioning is not clear enough. This study tried to clarify the effect of K-wires positioning and provide evidence for a more definite instruction.

METHODS

The sagittal position (SP) suitable for placing K-wires was evenly divided into SP 1-5 from anterior to posterior, and the finite element models of midpatella transverse fractures fixed by the figure-of-eight or figure-of-zero MTBW were built up at each SP. Separating displacement of the fracture, stress of the fracture, and stress of the internal fixations were measured at 45° knee flexion by using finite element analysis.

RESULTS

The separating displacement of the fracture was smaller at SP 3-5 (23% smaller than SP 1-2). From SP 1 to 5, the compression of the fracture surfaces increased (R = 0.99, P = 0.001); the improper stress area of the fracture surfaces decreased (R = - 0.96, P = 0.01), and so was the stress of K-wires (R = - 0.93, P = 0.02). However, the stress of stainless steel wires showed a stable trend.

CONCLUSIONS

The SP of K-wires plays a role in the function of MTBW in the surgical management of transverse patella fracture. At 45° knee flexion, posteriorly placed (close to the articular surface) K-wires enable optimal stability and stress for the fracture, which provides basis for the positioning of K-wires in clinical practice.

La-Doped biomimetic scaffolds facilitate bone remodelling by synchronizing osteointegration and phagocytic activity of macrophages

The capacity of osteoconduction held by HA/CS, osteoinduction by La³⁺, and biodegradability by a La-HA/CS composite, contributes to an ideal scaffold for osteointegration and remodelling.

Lanthanum phosphate/chitosan scaffolds enhance cytocompatibility and osteogenic efficiency via the Wnt/β-catenin pathway

BACKGROUND

Fabrication of porous scaffolds with great biocompatibility and osteoinductivity to promote bone defect healing has attracted extensive attention.

METHODS

In a previous study, novel lanthanum phosphate (LaPO4)/chitosan (CS) scaffolds were prepared by distributing 40- to 60-nm LaPO4 nanoparticles throughout plate-like CS films.

RESULTS

Interconnected three dimensional (3D) macropores within the scaffolds increased the scaffold osteoconductivity, thereby promoting cell adhesion and bone tissue in-growth. The LaPO4/CS scaffolds showed no obvious toxicity and accelerated bone generation in a rat cranial defect model. Notably, the element La in the scaffolds was found to promote osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) through the Wnt/β-catenin signalling pathway and induced high expression of the osteogenesis-related genes alkaline phosphatase, osteocalcin and Collagen I (Col-I). Moreover, the LaPO4/CS scaffolds enhanced bone regeneration and collagen fibre deposition in rat critical-sized calvarial defect sites.

CONCLUSION

The novel LaPO4/CS scaffolds provide an admirable and promising platform for the repair of bone defects.