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• GelMA/AlgMA and GelMA/AlgMA/hydroxyapatite bioinks were successfully synthesised using a one-pot strategy. • The novel bioinks were found to be highly suitable for DLP printing, offering high-resolution capabilities, and significantly expanding the range of available DLP bioinks. • The hydroxyapatite hybrid bioinks displayed superior bone repair abilities compared to pure organic bioinks. Three-dimensional (3D) bioprinting has revolutionized tissue engineering by enabling precise fabrication with bioinks. Among these techniques, digital light processing (DLP) stands out due to its exceptional resolution, speed, and biocompatibility. However, the progress of DLP is hindered by the limited availability of suitable bioinks. Currently, some studies involve simple mixing of different materials, resulting in bioinks that lack uniformity and photopolymerization characteristics. To address this challenge, we present an innovative one-pot synthesis method for bioinks based on methacrylated gelatin/alginate with hydroxyapatite (HAP). This approach offers significant advantages in terms of efficiency and uniformity. The synthesized bioinks demonstrate excellent printability, stability, and notably enhanced mechanical properties, facilitating optimal in vitro compatibility. Additionally, the HAP-hybrid bioinks printed scaffolds demonstrated impressive bone repair capabilities in vivo compared with pure organic bioinks. In conclusion, the Gel/Alg/HAP bioinks presented herein offer an innovative solution for DLP bioprinting within the field of bone tissue engineering. Their multifaceted advantages help overcome the limitations of restricted bioink choices, pushing forward the boundaries of bioprinting technology and contributing to the progress of regenerative medicine and tissue engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

Posttraumatic osteoarthritis (PTOA) patients are often diagnosed by X-ray imaging at a middle-late stage when drug interventions are less effective. Early PTOA is characterized by overexpressed matrix metalloprotease 13 (MMP13). Herein, we constructed an integrated diagnosis and treatment micelle modified with MMP13 enzyme-detachable, cyanine 5 (Cy5)-containing PEG, black hole quencher-3 (BHQ3), and cRGD ligands and loaded with siRNA silencing MMP13 (siM13), namely ERMs@siM13. ERMs@siM13 could be cleaved by MMP13 in the diseased cartilage tissues to detach the PEG shell, causing cRGD exposure. Accordingly, the ligand exposure promoted micelle uptake by the diseased chondrocytes by binding to cell surface αvβ3 integrin, increasing intracellular siM13 delivery for on-demand MMP13 downregulation. Meanwhile, the Cy5 fluorescence was restored by detaching from the BHQ3-containing micelle, precisely reflecting the diseased cartilage state. In particular, the intensity of Cy5 fluorescence generated by ERMs@siM13 that hinged on the MMP13 levels could reflect the PTOA severity, enabling the physicians to adjust the therapeutic regimen. Finally, in the murine PTOA model, ERMs@siM13 could diagnose the early-stage PTOA, perform timely interventions, and monitor the OA progression level during treatment through a real-time detection of MMP13. Therefore, ERMs@siM13 represents an appealing approach for early-stage PTOA theranostics.

Segmental bone defects, stemming from trauma, infection, and tumors, pose formidable clinical challenges. Traditional bone repair materials, such as autologous and allogeneic bone grafts, grapple with limitations including source scarcity and immune rejection risks. The advent of nucleic acid nanotechnology, particularly the use of DNA hydrogels in tissue engineering, presents a promising solution, attributed to their biocompatibility, biodegradability, and programmability. However, these hydrogels, typically hindered by high gelation temperatures (∼46 °C) and high construction costs, limit cell encapsulation and broader application. Our research introduces a novel polymer-modified DNA hydrogel, developed using nucleic acid nanotechnology, which gels at a more biocompatible temperature of 37 °C and is cost-effective. This hydrogel then incorporates tetrahedral Framework Nucleic Acid (tFNA) to enhance osteogenic mineralization. Furthermore, considering the modifiability of tFNA, we modified its chains with Aptamer02 (Apt02), an aptamer known to foster angiogenesis. This dual approach significantly accelerates osteogenic differentiation in bone marrow stromal cells (BMSCs) and angiogenesis in human umbilical vein endothelial cells (HUVECs), with cell sequencing confirming their targeting efficacy, respectively. In vivoexperiments in rats with critical-size cranial bone defects demonstrate their effectiveness in enhancing new bone formation. This innovation not only offers a viable solution for repairing segmental bone defects but also opens avenues for future advancements in bone organoids construction, marking a significant advancement in tissue engineering and regenerative medicine.

Minimally invasive surgery for hallux valgus correction, has been attracting great interests in the recent decades, due to the potential benefits of less pain, decreased recovery times, smaller scars with better cosmesis, and improved early post-operative range of motion. The most recent developments in minimally invasive surgery have evolved into the third generation with modifications of the chevron-type osteotomy. This evidence-based clinical guideline of the third generation minimally invasive surgery for hallux valgus is initiated and developed collectively by the Foot and Ankle Committee of Orthopedic Branch of Chinese Medical Doctor Association, Foot and Ankle Committee of Sports Medicine Branch of Chinese Medical Doctor Association, and Foot and Ankle Expert Committee of Orthopedic Branch of the Chinese Association of the Integrative Medicine. This clinical guideline provides recommendations for indications, contraindications, operative planning and techniques, post-operative management, management of complications, and prognosis of the third generation minimally invasive surgery for hallux valgus.

Patients with diabetes often experience fragile fractures despite normal or higher bone mineral density (BMD), a phenomenon termed the diabetic bone paradox (DBP). The pathogenesis and therapeutics opinions for diabetic bone disease (DBD) are not fully explored. In this study, we utilize two preclinical diabetic models, the leptin receptor-deficient db/db mice (DB) mouse model and the streptozotocin-induced diabetes (STZ) mouse model. These models demonstrate higher BMD and lower mechanical strength, mirroring clinical observations in diabetic patients. Advanced glycation end products (AGEs) accumulate in diabetic bones, causing higher non-enzymatic crosslinking within collagen fibrils. This inhibits intrafibrillar mineralization and leads to disordered mineral deposition on collagen fibrils, ultimately reducing bone strength. Guanidines, inhibiting AGE formation, significantly improve the microstructure and biomechanical strength of diabetic bone and enhance bone fracture healing. Therefore, targeting AGEs may offer a strategy to regulate bone mineralization and microstructure, potentially preventing the onset of DBD.

Nanostructured calcium phosphate porous microspheres are of great potential in drug delivery and bone regeneration due to their large specific surface area, biocompatibility, and similarity to inorganic component of osseous tissue. In this work, strontium (Sr)-doped amorphous calcium phosphate porous microspheres (SrAPMs) were synthesized through a microwave-hydrothermal method using fructose 1,6-bisphosphate trisodium salt as the source of phosphate ions. The SrAPMs showed a mesoporous structure and a relatively high specific area. Compared with the hydroxyapatite nanorods prepared by using Na2HPO4·12H2O as the phosphorus source, the SrAPMs with a higher specific surface area were more effective in drug loading using vancomycin as the antiobiotics of choice and consequently having a higher antibacterial efficiency both on agar plates and in broths. Furthermore, to assess the potential application of SrAPMs in bone defect repair, a novel biomimetic bone tissue-engineering scaffold consisting of collagen (Coll) and SrAPMs was constructed using a freeze-drying fabrication process. Incorporation of the SrAPMs not only improved the mechanical properties, but also enhanced the osteogenesis of rat bone marrow mesenchymal stem cells. The in vivo experiments demonstrated that the SrAPMs/Coll scaffolds remarkably enhanced new bone formation compared with the Coll and APMs/Coll scaffolds in a rat critical-sized calvarial defect model at 8 weeks postimplantation. In summary, SrAPMs developed in this work are promising as antibiotic carriers and may encourage bone formation when combined with collagen.

•Identification of patients with high risk for chronic ankle instability (CAI) is crucial for more effective and efficient treatment of acute lateral ankle sprain (LAS).•For patients who had at least 1 positive clinical finding in the 10-meter walk test, the anterior drawer test, or the inversion tilt test, magnetic resonance imaging (MRI) scans were helpful in predicting CAI after first-episode LAS.•Age, body mass index, posterior talofibular injury, large talus bone marrow lesion, and grade-2 tibiotalar joint effusion were 5 prognostic factors that MRI scanning used to predict CAI after first-episode LAS.

A new full time-domain nonlinear coupled method has been established and then applied to predict the responses of a Truss Spar in irregular wave. For the coupled analysis, a second-order time-domain approach is developed to calculate the wave forces, and a finite element model based on rod theory is established in three dimensions in a global coordinate system. In numerical implementation, the higher-order boundary element method (HOBEM) is employed to solve the velocity potential, and the 4th-order Adams-Bashforth-Moultn scheme is used to update the second-order wave surface. In deriving convergent solutions, the hull displacements and mooring tensions are kept consistent at the fairlead and the motion equations of platform and mooring-lines/risers are solved simultaneously using Newmark-βintegration scheme including Newton-Raphson iteration. Both the coupled quasi-static analysis and the coupled dynamic analysis are performed. The numerical simulation results are also compared with the model test results, and they coincide very well as a whole. The slow-drift responses can be clearly observed in the time histories of displacements and mooring tensions. Some important characteristics of the coupled responses are concluded.

Because China is becoming an aging society, the incidence of diabetes and diabetic foot have been increasing. Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates. Negative pressure wound therapy (NPWT) is one of the most effective techniques for the treatment of diabetic foot wounds and great progress, both in terms of research and its clinical application, has been made in the last 20 years of its development. However, due to the complex pathogenesis and management of diabetic foot, irregular application of NPWT often leads to complications, such as infection, bleeding and necrosis, that seriously affect its treatment outcomes. In 2020, under the leadership of Burns, Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association, the writing group for ‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’ was established with the participation of scholars from the specialized areas of burns, endocrinology, vascular surgery, orthopedics and wound repair. Drawing on evidence-based practice suggested by the latest clinical research, this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot. The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.

Introduction: Synthetic fibrous membranes unveil a promising field in anti-adhesion of tendons. Meanwhile, oriented nanofiber structures have been widely studied and used in the application of biomedical engineering, particularly in repairing and strengthening effects.Methods: In this study, a bi-layer poly(L-lactic acid) (PLLA) electrospun membrane was fabricated, in which the inner oriented fibrous layer was designed to promote tendon healing while outer random aligned layer was designed to prevent peritendinous adhesion.Results: It was found that fibroblasts were aligned along the oriented fiber of membranes in vitroand in a Leghorn chicken model. In biomechanical tests of repaired tendons, no significant difference was found between oriented fibrous membrane and blank control in maximum tensile strength; both oriented fibrous membranes and random fibrous membranes showed lower work of flexion than blank control, which was consistent with gross assessment.Conclusion: It was practicable to promote tendon healing while preventing adhesion viabi-layer PLLA membranes with an inner-oriented-fiber fabricated structure.