Jing Zhong's research while affiliated with Guangzhou Medical University and other places

Hyperplastic scars, especially keloids, have posed a significant clinical challenge due to their high recurrence rate. Compression therapy, a cost‐effective treatment, has demonstrated efficacy in reducing scarring and preventing recurrence. However, the compression methods exhibit limitations in adapting to the complex contours and accurately adjusting the treatment pressure, resulting in unsatisfactory treatment effects. In this study, silicone is chosen as the substrate layer ink, while the conductive ink is developed by incorporating nano‐carbon black into the polymer composite. These are printed alternately within the supported gels to construct an integrated orthotic device with precise pressure control capabilities and complex structures. Results demonstrated the printed orthosis displayed excellent mechanical properties, durability and biocompatibility. It can successfully detect various stress changes with short response times. The utilization of finite element analysis aided in the design of personalized orthosis to achieve optimal pressure for scar treatment. Finally, orthosis‐mediated pressure treatment is performed on rat tail scar models. By monitoring resistance value, it can be inferred whether the treatment pressure applied by orthosis fell within an optimal range. Overall, personalized piezoresistive anti‐scar orthoses offer an accurate and effective treatment method for scar. This innovative approach presents a novel strategy in the realm of personalized scar management.

Orthopedic insoles is the most commonly used nonsurgical treatment method for the flatfoot. Polyurethane (PU) plays a crucial role in the manufacturing of orthopedic insoles due to its high wear resistance and elastic recovery. However, preparing orthopedic insoles with adjustable hardness, high-accuracy, and matches the plantar morphology is challenging. Herein, a liquid crystal display (LCD) three-dimensional (3D) printer was used to prepare the customized arch-support insoles based on photo-curable and elastic polyurethane acrylate (PUA) composite resins. Two kinds of photo-curable polyurethanes (DL1000-PUA and DL2000-PUA) were successfully synthesized, and a series of fast-photocuring polyurethane acrylate (PUA) composite resins for photo-polymerization 3D printing were developed. The effects of different acrylate monomers on the Shore hardness, viscosity, and mechanical properties of the PUA composite resins were evaluated. The PUA-3-1 composite resin exhibited low viscosity, optimal hardness, and mechanical properties. A deviation analysis was conducted to assess the accuracy of printed insole. Furthermore, the stress conditions of the PUA composite resin and ethylene vinyl acetate (EVA) under the weight load of healthy adults were compared by finite element analysis (FEA) simulation. The results demonstrated that the stress of the PUA composite resin and EVA were 0.152 MPa and 0.285 MPa, and displacement were 0.051 mm and 3.449 mm, respectively. These results indicate that 3D-printed arch-support insole based on photocurable PUA composite resin are high-accuracy, and can reduce plantar pressure and prevent insoles premature deformation, which show great potential in the physiotherapeutic intervention for foot disorders.

The immunotherapeutic effect elicited by photodynamic therapy (PDT) is attenuated by tumor defense mechanisms associated with glutamine metabolism, including the metabolic regulation of redox homeostasis and the limitation of the immunosuppressive tumor microenvironment (ITM). Herein, a carrier-free immunotherapeutic nanobooster C9SN with dual synergistic effects was constructed by the self-assembly of glutaminase (GLS) inhibitor compound 968 (C968) and photosensitizer Chlorin e6. C968-mediated GSH deprivation through inhibiting glutamine metabolism prevented PDT-generated reactive oxygen species from being annihilated by GSH, amplifying intracellular oxidative stress, which caused severe cell death and also enhanced the immunogenic cell death (ICD) effect. In addition, genome-wide analysis was carried out using RNA-sequencing to evaluate the changes in cell transcriptome induced by amplifying oxidative stress. Thereafter, neoantigens generated by the enhanced ICD effect promoted the maturation of dendritic cells, thereby recruiting and activating cytotoxic T lymphocytes (CTLs). Meanwhile, C9SN remodeled the ITM by blocking glutamine metabolism to polarize M2-type tumor-associated macrophages (TAMs) into M1-type TAMs, which further recruited and activated the CTLs. Ultimately, this immunotherapeutic nanobooster suppressed primary and distant tumors. This "kill two birds with one stone" strategy would shed light on enhancing tumor immunogenicity and alleviating tumor immunosuppression to improve the immunotherapeutic effect of PDT.

Alveolar ridge preservation techniques have been developed as a possible method to maintain the optimum ridge contour and dimensions. Grafting a bone substitute is paramount to prevent alveolar ridge resorption after tooth extraction. However, it remains a great challenge to develop alveolar ridge preservation materials with sufficient mechanical strength, bioactivity, and osteoinductivity and favorable tooth extraction socket morphological matching. In this work, a novel photocrosslinked composite ink consisting of nacre, polyurethane (PU) and polyhedral oligomeric silsesquioxane (POSS) was prepared and used to fabricate 3D porous scaffolds for alveolar ridge preservation. This nacre/PU/POSS (NPP) composite was characterized in terms of its rheological behavior, mechanical properties, and surface hydrophilicity. The biomineralization of these NPP scaffolds was confirmed via in vitro experiments. MC3T3-E1 cells were distributed homogeneously on the NPP scaffolds and stimulated cellular proliferation. When the NPP scaffolds were grafted into the sockets after extraction of mandibular incisors, the height and width of alveolar bone resorption were reduced, and new bone formation was observed. These NPP composites are promising scaffold materials for alveolar ridge preservation and 3D printing of bone grafts in future.

High-density polyethylene (HDPE) is a promising material for the development of scaffold implants for auricle reconstruction. However, preparing a personalized HDPE auricle implant with favorable bioactive and antibacterial functions to promote skin tissue ingrowth is challenging. Herein, we present 3D-printed HDPE auricle scaffolds with satisfactory pore size and connectivity. The layer-by-layer (LBL) approach was applied to achieve the improved bioactive and antibacterial properties of these 3D printed scaffolds. The HDPE auricle scaffolds were fabricated using an extrusion 3D printing approach, and the individualized macrostructure and porous microstructure were both adjusted by the 3D printing parameters. The polydopamine (pDA) coating method was used to construct a multilayer ε-polylysine (EPL) and fibrin (FIB) modification on the surface of the 3D HDPE scaffold via the LBL self-assembly approach, which provides the bioactive and antibacterial properties. The results of the in vivo experiments using an animal model showed that LBL-coated HDPE auricular scaffolds were able to significantly enhance skin tissue ingrowth and ameliorate the inflammatory response caused by local stress. The results of this study suggest that the combination of the 3D printing technique and surface modification provides a promising strategy for developing personalized implants with biofunctional coatings, which show great potential as a scaffold implant for auricle reconstruction applications.

Skin necrosis is the most common complication in total auricular reconstruction, which is mainly induced by vascular compromise and local stress concentration of the overlying skin. Previous studies generally emphasized the increase in the skin flap blood supply, while few reports considered the mechanical factors. However, skin injury is inevitable due to uneasily altered loads generated by the intraoperative continuous negative suction and uneven cartilage framework structure. Herein, this study aims to attain the stable design protocol of the ear cartilage framework to decrease mechanical damage and the incidence of skin necrosis. Finite element analysis was initially utilized to simulate the reconstructive process while the shape optimization technique was then adopted to optimize the three-pretested shape of the hollows inside the scapha and fossa triangularis under negative suction pressure. Finally, the optimal results would be output automatically to meet clinical requirement. Guided by the results of FE-based shape optimization, the optimum framework with the smallest holes inside the scapha and fossa triangularis was derived. Subsequent finite element analysis results also demonstrated the displacement and stress of the post-optimized model were declined 64.9 and 40.1%, respectively. The following clinical study was performed to reveal that this new design reported lower rates of skin necrosis decrease to 5.08%, as well as the cartilage disclosure decreased sharply from 14.2 to 3.39% compared to the conventional method. Both the biomechanical analysis and the clinical study confirmed that the novel design framework could effectively reduce the rates of skin necrosis, which shows important clinical significance for protecting against skin necrosis.

We herein firstly reported a dual-responsive peptide substrate (Comp.1) for preparing self-assembly nanomaterials triggered by pH and legumain. The dual-responsive self-assembly of Comp.1 in glioma cells enabled it long-time retention in lysosomes, S phase arrest, and locking cells growth. We verified the blocked degradation of HIF-1α in lysosomes played a key role in cell cycle arrest and decreased DNA replication. This work illustrated the disturbance of lysosomal function by self-assembly nanomaterials as a promising strategy for inhibiting the glioma cells growth.