Tissue-engineered scaffolds are an effective method for the treatment of bone defects, and their structure and function are essential for bone regeneration. Digital light processing (DLP) printing technology has been widely used in bone tissue engineering (BTE) due to its high printing resolution and gentle printing process. As commonly used bioinks, synthetic polymers such as polyethylene glycol diacrylate (PEGDA) and Pluronic F127 diacrylate (F127DA) have satisfactory printability and mechanical properties but usually lack sufficient adhesion to cells and tissues. Here, a compound BTE scaffold based on PEGDA, F127DA, and gelatin methacrylate (GelMA) was successfully prepared using DLP printing technology. The scaffold not only facilitated the adhesion and proliferation of cells, but also effectively promoted the osteogenic differentiation of mesenchymal stem cells in an osteoinductive environment. Moreover, the bone tissue volume/total tissue volume (BV/TV) of the GelMA/PEGDA/F127DA (GPF) scaffold in vivo was 49.75 ± 8.50%, higher than the value of 37.10 ± 7.27% for the PEGDA/F127DA (PF) scaffold and 20.43 ± 2.08% for the blank group. Therefore, the GPF scaffold prepared using DLP printing technology provides a new approach to the treatment of bone defects.

Intervertebral disc degeneration (IVDD) stands as the foremost contributor to low back pain (LBP), imposing a substantial weight on the world economy. Traditional treatment modalities encompass both conservative approaches and surgical interventions; however, the former falls short in halting IVDD progression, while the latter carries inherent risks. Hence, the quest for an efficacious method to reverse IVDD onset is paramount. Biomaterial delivery systems, exemplified by hydrogels, microspheres, and microneedles, renowned for their exceptional biocompatibility, biodegradability, biological efficacy, and mechanical attributes, have found widespread application in bone, cartilage, and various tissue engineering endeavors. Consequently, IVD tissue engineering has emerged as a burgeoning field of interest. This paper succinctly introduces the intervertebral disc (IVD) structure and the pathophysiology of IVDD, meticulously classifies biomaterials for IVD repair, and reviews recent advances in the field. Particularly, the strengths and weaknesses of biomaterials in IVD tissue engineering are emphasized, and potential avenues for future research are suggested.

Spinal cord injury (SCI) is a severe central nervous system injury without effective therapies. PANoptosis is involved in the development of many diseases, including brain and spinal cord injuries. However, the biological functions and molecular mechanisms of PANoptosis-related genes in spinal cord injury remain unclear. In the bioinformatics analysis of public data of SCI, the differentially expressed genes (DEGs) identified by GSE151371 were hybridized with PANoptosis-related genes (PRGs) to obtain differentially expressed PANoptosis-related genes (DE-PRGs). Through three machine learning algorithms, we obtained the hub genes. Then, we constructed functional analysis, drug prediction, regulatory network construction, and immune infiltrating cell analysis. Finally, the expression of the hub gene was verified in GSE93561, GSE45376, and qRT-PCR analysis. Through the above analysis, 14 DE-PRGs were obtained by intersecting 3582 DEGs with 46 PRGs. Five key hub genes, CASP4, GSDMB, NAIP, NLRC4, and NLRP3, were obtained by 3 machine learning algorithms. All five hub genes were enriched in phagocytosis mediated by FC GAMMA R. The 11 immune cells were significantly different between spinal cord injury (SCI) group and human control (HC) group, such as mast cell and gamma delta T cell. The transcription factor (TF)-hub gene network contained 10-nodes (4 hub genes and 6 TFs) and 8-edges. The miRNA-hub gene network consisting of 5-nodes (3 hub genes and 2 miRNAs) and 3-edges was constructed. Moreover, the CASP4 predicted 1 small molecule drug and NLRP3 predicted 9 small molecule drugs. Finally, the expression of 5 hub genes were significantly different in GSE45376 and GSE93561 (SCI vs. HC) and mice SCI model (Sham vs. SCI). Collectively, we identified 5 hub genes (CASP4, GSDMB, NAIP, NLRC4, and NLRP3) associated with PANoptosis, providing potential directions for treating spinal cord injury.

Managing severe bleeding, particularly in soft tissues and visceral injuries, remains a significant challenge in trauma and surgical care. Traditional hemostatic methods often fall short in wet and dynamic environments. This study addresses the critical issue of severe bleeding in soft tissues, proposing an innovative solution using a polyethylene glycol (PEG)-based hydrogel combined with zinc oxide (ZnO). The developed hydrogel forms a dual-network structure through amide bonds and metal ion chelation, resulting in enhanced mechanical properties and adhesion strength. The hydrogel, exhibiting excellent biocompatibility, is designed to release zinc ions, promoting coagulation and accelerating hemostasis. Comprehensive characterization, including gelation time, rheological properties, microstructure analysis, and swelling behavior, demonstrates the superior performance of the PEG/ZnO hydrogel compared to traditional PEG hydrogels. Mechanical tests confirm increased compression strength and adhesive properties, which are crucial for withstanding tissue dynamics. In vitro assessments reveal excellent biocompatibility and enhanced procoagulant ability attributed to ZnO. Moreover, in vivo experiments using rat liver and tail bleeding models demonstrate the remarkable hemostatic performance of the PEG/ZnO hydrogel, showcasing its potential for acute bleeding treatment in both visceral and peripheral scenarios.

Janus hydrogels, distinguished by their dual-sided structure with distinct physical and chemical properties, have garnered significant attention in the medical field, particularly for applications in drug delivery, tissue engineering, and wound healing. Their ability to simultaneously perform multiple functions, such as targeted drug release and biomimetic tissue interaction, positions them as a promising platform for advanced therapeutic strategies. The growing interest in these hydrogels is primarily driven by their multifunctionality and capacity to address complex biological needs. This review delves into the design, fabrication methods, and applications of Janus hydrogels in medicine, focusing on their potential to overcome the limitations of conventional therapies and providing a comprehensive overview of their role in contemporary biomedical applications.

Laminectomy is a commonly performed surgical procedure by orthopedic and neurosurgeons, aimed at alleviating nerve compression and reducing pain. However, in some cases, excessive proliferation of fibrous scar tissue in the epidural space post-surgery can lead to persistent and intractable lower back pain, a condition known as Failed Back Surgery Syndrome (FBSS). The persistent fibrous tissue causes both physical and emotional distress for patients and also makes follow-up surgeries more challenging due to reduced visibility and greater technical difficulty. It has been established that the application of biomaterials to prevent epidural fibrosis post-lumbar surgery is more beneficial than revision surgeries to relieve dural fibrosis. Hydrogel-based biomaterials, with their excellent biocompatibility, degradability, and injectability and tunable mechanical properties, have been increasingly introduced by clinicians and researchers. This paper, building on the foundation of epidural fibrosis, primarily discusses the strategies for the preparation of natural and polymeric biomaterials to prevent epidural fibrosis, their physicochemical properties, and their ability to mitigate the excessive proliferation of fibroblasts. It also emphasizes the challenges that need to be addressed to translate laboratory research into clinical practice and the latest advancements in this field.