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Vascular dysfunction severely hinders the healing process of diabetic wounds. Therefore, a radially structured fibrous membrane was fabricated through electrospinning by using a polycaprolactone (PCL) and polyvinylpyrrolidone (PVP) mixed solution containing copper peroxide nanoparticles (CPs) as the chemodynamic therapy (CDT) agents, aiming to simultaneously accelerate tissue regeneration and angiogenesis. The fabricated membrane allowed for the in situ H2O2 generation activated by the acidic diabetic microenvironment and the subsequent Fenton-type reactions to realize 99.4% elimination against Staphylococcus aureus. Besides, the released Cu2+ ions significantly enhanced the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in human umbilical vein endothelial cells (HUVECs), and they showed enhanced in vitro angiogenesis. Interestingly, the CP-embedded membrane also guided cell spreading and orientated migration of L929 fibroblasts along the fiber distribution through the radially aligned topology. The in vivo implantation indicated that the raidally structured membrane modified by CPs not only dramatically accelerated wound healing of diabetic Sprague–Dawley (SD) rats in 14 days but also promoted angiogenesis in wound sites. The combination of the in situ CDT with the radially structured morphology of the functional membrane is highly promising in applications to promote diabetic wound healing through anti-infection and revascularization.

Study Design Comparative study Objective To compare manual and deep learning-based automated measurement of Cobb angle in adolescent idiopathic scoliosis. Methods We proposed a fully automated framework to measure the Cobb angle of AIS patients. Whole-spine images of 500 AIS individuals were collected. 200 digital radiographic (DR) images were labeled manually as training set, and the remaining 300 images were used to validate by mean absolute error (MAE), Pearson or spearman correlation coefficients, and intra/interclass correlation coefficients (ICCs). The relationship between accuracy of vertebral boundary identification and the subjective image quality score was evaluated. Results The PT, MT, and TL/L Cobb angles were measured by the automated framework within 300 milliseconds. Remarkable 2.92° MAE, .967 ICC, and high correlation coefficient (r = .972) were obtained for the major curve. The MAEs of PT, MT, and TL/L were 3.04°, 2.72°, and 2.53°, respectively. The ICCs of these 3 curves were .936, .977, and .964, respectively. 88.7% (266/300) of cases had a difference range of ±5°, with 84.3% (253/300) for PT, 89.7% (269/300) for MT, and 93.0% (279/300) for TL/L. The decreased bone/soft tissue contrast (2.94 vs 3.26; P=.039) and bone sharpness (2.97 vs 3.35; P=.029) were identified in the images with MAE exceeding 5°. Conclusion The fully automated framework not only identifies the vertebral boundaries, vertebral sequences, the upper/lower end vertebras and apical vertebra, but also calculates the Cobb angle of PT, MT, and TL/L curves sequentially. The framework would shed new light on the assessment of AIS curvature.

Editorial on the Research Topic Biomaterial advances in intervertebral disc degenerationNeck and back pain are ubiquitous in modern society, leading to serious lifelong disability and placing an enormous socioeconomic burden on the global healthcare system. Although the etiology of neck and back pain is multifaceted and still incompletely understood, intervertebral disc degeneration (IDD) is considered to be the most significant contributor. The current treatments for IDD, including medication, surgery, and others, are limited to symptomatic relief but fail to restore the structure and homeostasis of the intervertebral disc. The failure leads to the steady deterioration of compromised discs and undesirable consequences, such as recrudescence or adjacent vertebral disease. Tissueengineered approaches hold great promise for the treatment of IDD. Gullbrand et al. designed and manufactured a disc-like angle ply structure (DAPS), which has distinct components that mimic the structure of the native disc. The long-term integration and mechanical function of engineered DAPS in vivo, even in large animal models have been successfully tested (Gullbrand et al., 2018). After that, Sloan et al. demonstrated that combined nucleus pulposus augmentation using hyaluronic acid injection and annulus fibrosus repair using photo cross-linked collagen patch restore nucleus pulposus hydration, heal annulus fibrosus defects and maintain native torsional and compressive stiffness up to 6 weeks after discectomy injury in a large animal model. These studies move this approach a step towards translational feasibility (Sloan et al., 2020).Given the indispensable role of biomaterials in tissue engineering for IDD, we prepared this Research Topic to summarize the progress in this field. The harsh microenvironment of IDD is not suitable for disc regeneration. Therefore, various therapeutic agents, including small molecular, growth factor, exosome, and nucleic acids-based drugs are employed to reduce the inflammatory response, promote extracellular matrix synthesis, and direct cell differentiation to create a good regenerative microenvironment. Traditional drug delivery such as systemic administration or via in situ injection has low drug availability and high offtarget toxicity. Liu et al. have systematically demonstrated that biomaterials-based nanodrug delivery systems have improved treatment results of therapeutic agents for IDD because of their good biodegradability, biocompatibility, precise targeted specific drug delivery, prolonged drug release time, and enhanced drug efficacy (Liu et al., 2023). Except for drug delivery, a good cell carrier is critical for tissue regeneration. The microsphere is a class of three-dimensional spherical structures with an average particle size of 1-1000 μm that could be used in cell carrying and biomedical substance delivery. Guo et al. recently reviewed the use of various microspheres for disc regeneration and clearly demonstrated that the high

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