Graphene-based materials (GMs) have great application prospects in bone tissue engineering due to their osteoinductive ability and antimicrobial activity. GMs induce osteogenic differentiation through several mechanisms and pathways in bone tissue engineering. First of all, the surface and high hardness of the porous folds of graphene or graphene oxide (GO) can generate mechanical stimulation to initiate a cascade of reactions that promote osteogenic differentiation without any chemical inducers. In addition, change of the extracellular matrix (ECM), regulation of macrophage polarization, the oncostatin M (OSM) signaling pathway, the MAPK signaling pathway, the BMP signaling pathway, the Wnt/β-catenin signaling pathway, and other pathways are involved in GMs' regulation of osteogenesis. In bone tissue engineering, GMs prevent the formation of microbial biofilms mainly through preventing microbial adhesion and killing them. The former is mainly achieved by reducing surface free energy (SFE) and increasing hydrophobicity. The latter mainly includes oxidative stress and photothermal/photodynamic effects.Graphene and its derivatives (GDs) are mainly combined with bioactive ceramic materials, metal materials and macromolecular polymers to play an antimicrobial effect in bone tissue engineering. Concentration, number of layers, and type of GDs often affect the antimicrobial activity of GMs. In this paper, we reviewed relevant osteoinductive and antimicrobial mechanisms of GMs and their applications in bone tissue engineering.

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Nano (or) microfiber structures made from biodegradable polymers offer many benefits for biomedical applications, including the tissue engineering system. In this study, a mixture of poly (lactic acid) (PLA)/gelatin (GEL) conjugated epidermal growth factor (EGF) electrospun nanofiber scaffolds, which may have potential applications for nursing care of diabetic wound healing. The amount of EGF conjugation on the PLA/GEL nanofibers was quantitated by X-ray photoelectron spectroscopy. A morphological examination of the electrospun nanofibers was performed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which has bead-free morphology nanofibers. After characterizing, the PLA/GEL and PLA/GEL/EGF scaffolds were selected for further investigation based on their superior mechanical properties, including tensile strength, maximum elongation, and tensile modulus. We evaluated the antibacterial activity, cell proliferation and the efficiency of diabetic wound healing in vivo. The antibacterial effect of EGF present in the PLA/GEL nanofibers was assessed using the zone inhibition test against S. aureus and E. coli. In vitro cell proliferation activity was well maintained after the PLA/GEL conjugation and was compared to that of EGF with L929 fibroblast cells. The nanofiber PLA/GEL conjugated with EGF exerted greater curative activities in vivo compared to the control groups or EGF solutions. This study showed that the nanofiber PLA/GEL in combination with EGF could potentially be used as a novel material for nursing care of wound healing by antibacterial, increasing inflammatory cell, and re-epithelialization.

Organ transplantation is the ultimate treatment for end-stage diseases such as heart and liver failure. However, the severe shortage of donor organs has limited the organ transplantation progress. Xenogeneic stem cell transplantation provides a new strategy to solve this problem. Researchers have shown that xenogeneic stem cell transplantation has significant therapeutic effects and broad application prospects in treating liver failure, myocardial infarction, advanced type 1 diabetes mellitus, myelosuppression, and other end-stage diseases by replacing the dysfunctional cells directly or improving the endogenous regenerative milieu. In this review, the sources, problems and solutions, and potential clinical applications of xenogeneic stem cell transplantation will be discussed.

Background Cervicofacial space infections are potentially life-threatening, which require accurate diagnosis, early incision, and adequate drainage. The utilization of computed tomography (CT) in cervicofacial space infections has significantly increased for its advantages in the evaluation of abscesses, its availability, and low cost. However, the clinical value of preoperative CT imaging in cervicofacial space infections remains controversial for its poor specificity, radiation exposure, potential complications, and extra cost. We, therefore, investigated whether CT examination should be used as a routine examination in the treatment of patients with cervicofacial space infections. Methods A retrospective study of all patients affected by cervicofacial space infections that received incision and drainage surgery from Jan 2016 to Dec 2020 was performed at West China Hospital of Stomatology at Sichuan University. Patients were divided into two groups: the group with preoperative CT and without preoperative CT. Outcomes, including reoperation rate, missed diagnosis rate, days of symptom relief, length of stay, duration of surgery, and total cost of hospitalization, were analyzed. Results Out of n = 153 patients, 108 patients underwent surgery with preoperative CT and 45 patients without preoperative CT. The reoperation rate in the preoperative CT group (6/108, 5.6%) was significantly lower (P = 0.00) than that in the group without preoperative CT (10/45, 22.2%). Significant reduction of missed diagnosis rate (P = 0.00), days of symptom relief (P = 0.01), length of stay(P = 0.03), and duration of surgery (P = 0.01) were detected in the preoperative CT group. The results demonstrated that the utilization of preoperative CT can reduce the missed diagnosis rate and repeated surgery complications. Conclusions We recommend preoperative CT as a routine examination in cervicofacial space infections.