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A biomaterial that can remove remaining oral squamous cell carcinoma (OSCC) cells and repair oral mucosal damage is urgently needed. This graphical abstract described a composite scaffold that would simultaneously kill OSCC cells and promote the regeneration of the oral mucosa. [Display omitted] • Quercetin acts as an inhibitor when heat shock proteins make tumor cells more resistant to photothermal therapy. • Ti 3 C 2 MXene and quercetin are effectively carried by scaffold made of collagen and silk fibroin. • The composite scaffold successfully limits tumor cells migration and promotes oral mucosal defects regeneration. The most prevalent oral and maxillofacial cancer is oral squamous cell carcinoma (OSCC). Patient survival is compromised by relapse due to post-operative tumor remnants and significant mucosal defects. Photothermal therapy (PTT) is used to ablate local malignancies, but the capacity of tumor cells to resist it is correlated with the overexpression of heat shock protein 70 (HSP70). In this work, PTT and tissue engineering scaffold were rationally integrated to construct a Ti 3 C 2 MXene, collagen, silk fibroin and quercetin composite scaffold (M-CSQ scaffold), a 3D printed biomaterial that simultaneously kill OSCC cells and promote the regeneration of the mucosal defects. The M-CSQ scaffolds were prepared by cryogenic 3D printing and freeze-drying techniques with sufficient pores that allow an abundant cell migration and provide a proliferation space. Ti 3 C 2 MXene has excellent photothermal conversion ability and stability. Quercetin targeted HSP70 to decrease its expression in OSCC cells, consequently weakening their resistance to high temperature and enhancing the effect of PTT. The M-CSQ scaffold effectively killed OSCC cells in vitro and inhibited tumor growth in vivo. In addition, the M-CSQ scaffold provided adhesion sites for Sprague-Dawley rat (SD rat) buccal mucosal fibroblasts and promoted the repair of buccal mucosal wounds. [ABSTRACT FROM AUTHOR]

[Display omitted] The tissue engineering is a promising method for cartilage regeneration studies. The rough in vivo initial repair environment of articular cartilage is a challenge for the development of cartilage tissue engineering. Hereon, in this study, a silk fibroin/collagen type II scaffold was designed. The optimal mechanical environment for chondrocyte/scaffold complex in vitro maturation culture was determined and in vitro cultured mature artificial cartilage was evaluated for in vivo defect repair. Our research shows that the silk fibroin/collagen type II scaffold has good performance and can meet the special requirements of cartilage repair. 10 % compressive strain is the optimal compressive loading in vitro. Under optimal compression loading in vitro , chondrocytes can proliferate and grow rapidly on the scaffold to achieve better "maturation". The in vitro cultured chondrocyte/scaffold complex effectively improves the cartilage repair effect after implantation. The compressive elastic modulus of the new tissue reached 0.682 ± 0.010 MPa after 12 weeks of repair (0.714 ± 0.011 MPa for the surrounding host cartilage). Therefore, this study not only enhance the effect of cartilage repair but also provides a promising strategy for mechanical stimulation to promote functional in situ regeneration of articular cartilage. [ABSTRACT FROM AUTHOR]

Abstract: The microstructures of lath martensite in 25CrMo48V steel quenched at 900°C and tempered at 600–700°C for 5–105min were characterized by field emission scanning electron microscopy (FESEM), electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM). The tensile properties of 25CrMo48V martensitic steel were evaluated from the specimens subjected to various tempering temperature and time. The result shows that with the tempering temperature and time decreased, the refinement of martensitic packet, block and lath can take place and induce the enhancement of the yield strength. The yield strength follows the classical formula of Hall–Petch relationship with the packet size and block width, and the value of ky is 102.7Nmm−3/2 and 46.6Nmm−3/2 respectively. The yield strength is more dependent on the packet size than the block width, while the martensitic lath is the minimum structure unit controlling the yield strength of the steel. [Copyright &y& Elsevier]