摘要：At present,the clinical reconstruction of the auricle usually adopts the strategy of taking autologous costal *** method has great trauma to patients,poor plasticity and inaccurate ***-dimensional(3d)printing technology has made a great breakthrough in the clinical application of orthopedic *** study explored the combination of 3d printing and tissue engineering to precisely reconstruct the ***,a polylactic acid(PLA)polymer scaffold with a precisely customized patient appearance was fabricated,and then auricle cartilage fragments were loaded into the 3d-printed porous PLA scaffold to promote auricle *** vitro,gelatin methacrylamide(GelMA)hydrogels loaded with different sizes of rabbit ear cartilage fragments were studied to assess the regenerative activity of various autologous cartilage *** vivo,rat ear cartilage fragments were placed in an accurately designed porous PLA polymer ear scaffold to promote auricle *** results indicated that the chondrocytes in the cartilage fragments could maintain the morphological phenotype in *** three months of implantation observation,it was conducive to promoting the subsequent regeneration of cartilage in *** autologous cartilage fragments combined with 3d printing technology show promising potential in auricle reconstruction.

摘要：Micro-/nano-patterns on hydrogels are widely used in cell ***,manufacturing molds with traditional lithography is time-consuming and *** addition,the excessive demolding force can easily damage patterns since biocompatible hydrogels are ultra-soft or ***,we presented a novel method for rapid and mass fabrication of cell ***-precision three-dimensional(3d)printing was used to manufacture a mold with a resolution of 2µm,and the gelatin-based hydrogel was cured by thermal–photo-crosslinking so that the low-concentration and low-substitutionrate hydrogel could be demolded *** found that pre-cooling before illumination made gelatin-based hydrogels resilient due to the partial regain of triple-helix *** this method,arbitrarily customized hydrogel patterns with a feature size of 6–80µm can be fabricated stably and at low *** cardiomyocytes were seeded on ultra-soft hydrogels with parallel groove structures,a consistent and spontaneous beating with 216 beats per minute(BPM)could be observed,approaching the natural beating rate of rat hearts(300 BPM).Overall,this work provides a general scheme for manufacturing cell patterns which has great potential for cell ethology and tissue repair.

摘要：Over millions of years of evolution,nature has created organisms with overwhelming performances due to their unique materials and structures,providing us with valuable inspirations for the development of next-generation biomedical *** a promising new technology,3d printing enables the fabrication of multiscale,multi-material,and multi-functional threedimensional(3d)biomimetic materials and structures with high precision and great *** manufacturing challenges of biomedical devices with advanced biomimetic materials and structures for various applications were overcome with the flourishing development of 3d printing *** this paper,the state-of-the-art additive manufacturing of biomimetic materials and structures in the field of biomedical engineering were *** kinds of biomedical applications,including implants,lab-on-chip,medicine,microvascular network,and artificial organs and tissues,were respectively *** technical challenges and limitations of biomimetic additive manufacturing in biomedical applications were further investigated,and the potential solutions and intriguing future technological developments of biomimetic 3d printing of biomedical devices were highlighted.

摘要：Tissue engineering is an emerging means for resolving the problems of tissue repair and organ replacement in regenerative *** supply of nutrients and oxygen to cells in large-scale tissues has led to the demand to prepare blood ***-based tissue engineering approaches are effective methods to form new blood vessel *** demand for blood vessels prompts systematic research on fabrication strategies of vascular scaffolds for tissue *** advances in 3d printing have facilitated fabrication of vascular scaffolds,contributing to broad prospects for tissue *** review presents state of the art on modeling methods,print materials and preparation processes for fabrication of vascular scaffolds,and discusses the advantages and application fields of each ***,significance and importance of scaffold-based tissue engineering for vascular regeneration are *** materials and preparation processes are discussed in *** a focus is placed on preparation processes based on 3d printing technologies and traditional manufacturing technologies including casting,electrospinning,and Lego-like *** related studies are *** of vascular scaffolds to clinical application is ***,four trends of 3d printing of tissue engineering vascular scaffolds are presented,including machine learning,near-infrared photopolymerization,4d printing,and combination of self-assembly and 3d printing-based methods.

摘要：Three-dimensional(3d)-printed scaffolds have attracted considerable attention in recent years as they provide a suitable environment for bone cell tissue regeneration and can be customized in *** many other challenges,the material composition and geometric structure have major impacts on the performance of *** and tricalcium phosphate(HA/TCP),as the major constituents of natural bone and teeth,possess attractive biological properties and are widely used in bone scaffold *** fabrication methods have been investigated in attempts to achieve HA/TCP scaffolds with microporous structure enabling cell growth and nutrient ***,current 3d printing methods can only achieve the fabrication of HA/TCP scaffolds with certain range of microporous *** overcome this challenge,we developed a slurry-based microscale mask image projection stereolithography,allowing us to form a HA/TCP-based photocurable suspension with complex geometry including biomimetic features and hierarchical ***,the curing performance and physical properties of the HA/TCP suspension were investigated,and a circular movement process for the fabrication of highly viscous HA/TCP suspension was *** on these investigations,the scaffold composition was *** determined that a 30 wt%HA/TCP scaffold with biomimetic hierarchical structure exhibited superior mechanical properties and *** proliferation was investigated in vitro,and the surgery was conducted in a nude mouse in vivo model of long bone with cranial neural crest cells and bone marrow mesenchymal stem *** results showed our 3d-printed HA/TCP scaffold with biomimetic hierarchical structure is biocompatible and has sufficient mechanical strength for surgery.

摘要：The major drawback associated with PEEK implants is their biologically inert surface,which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bone *** this study,polyetheretherketone(PEEK)was incorporated with calcium hydroxyapatite(cHAp)to fabricate a PEEK-cHAp biocomposite,using the fused deposition modeling(FdM)method and a surface treatment strategy to create microporous architectures onto the filaments of PEEK lattice ***,nanostructure and morphological tests of the PEEK-cHAp biocomposite were modeled and analyzed on the FdM-printed PEEK-cHAp biocomposite sample to evaluate its mechanical and thermal strengths as well as in vitro cytotoxicity via a scanning electron microscope(SEM).A technique was used innovatively to create and investigate the porous nanostructure of the PEEK with controlled pore size and distribution to promote cell penetration and biological integration of the PEEK-cHAp into the *** vivo tests demonstrated that the surface-treated micropores facilitated the adhesion of newly regenerated soft tissues to form tight implant-tissue interfacial bonding between the cHAp and *** results of the cell culture depicted that PEEK-cHAp exhibited better cell proliferation attachment spreading and higher alkaline phosphatase activity than PEEK *** islands formed on the PEEK-cHAp composite after immersion in simulated body fluid of dulbecco’s modified Eagle medium(dMEM)for 14 days and grew continuously with more or extended *** microstructure treatment of the crystallinity of PEEK was comparatively and significantly different from the PEEK-cHAp sample,indicating a better treatment of *** in vitro results obtained from the PEEK-cHAp biocomposite material showed its biodegradability and performance suitability for bone *** study has potential applications in the field of biomedical engineering to strengthen the conceptual kn

摘要：Bone is known to have a natural function to heal ***,if the bone damage is beyond a critical degree,intervention such as bone grafting may be *** this work,the fabrication of a novel bone scaffold composed of natural bone components and polycaprolactone(PCL)using 3d printing is put forward.α1,3-galactosyltransferase deficient pigs were used as the donor source of a *** porcine bone(dCB)with attenuated immunogenicity was used as the natural component of the scaffold with the aim to promote bone *** 3d printed dCB-PCL scaffolds combined essential advantages such as uniformity of the interconnected macropores and high porosity and enhanced compressive *** biological properties of the dCB-PCL scaffolds were evaluated by studying cell adhesion,viability,alkaline phosphatase activity and osteogenic gene expression of human bone marrow-derived mesenchymal stem *** in vitro results demonstrated that the dCB-PCL scaffolds exhibit an enhanced performance in promoting bone differentiation,which is correlated to the dCB ***,critical-sized cranial rat defects were used to assess the effect of dCB-PCL scaffolds on bone regeneration in *** results confirm that in comparison with PCL scaffolds,the dCB-PCL scaffolds can significantly improve new bone formation in cranial ***,the proposed 3d printed dCB-PCL scaffolds emerge as a promising regeneration alternative in the clinical treatment of large bone defects.

摘要：Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering *** present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue *** experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and *** resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3d)*** studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural *** scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue *** tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of *** enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue *** vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold *** addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3d structures,demonstrating its pote

摘要：Tissue engineering(TE)continues to be widely explored as a potential solution to meet critical clinical needs for diseased tissue replacement and tissue *** this study,we developed a poly(2-hydroxyethyl methacrylate-co-methacrylic acid)(pHEMA-co-MAA)based hydrogel loaded with newly synthesized conductive poly(3,4-ethylene-dioxythiophene)(PEdOT)and polypyrrole(PPy)nanoparticles(NPs),and subsequently processed these hydrogels into tissue engineered constructs via three-dimensional(3d)*** presence of the NPs was critical as they altered the rheological properties during ***,all samples exhibited suitable shear thinning properties,allowing for the development of an optimized processing window for 3d *** were 3d printed into pre-determined disk-shaped configurations of 2 and 10 mm in height and diameter,*** observed that the NPs disrupted the gel crosslinking efficiencies,leading to shorter degradation times and compressive mechanical properties ranging between 450 and 550 *** conductivity of the printed hydrogels increased along with the NP concentration to(5.10±0.37)×10^(−7)S/*** vitro studies with cortical astrocyte cell cultures demonstrated that exposure to the pHEMA-co-MAA NP hydrogels yielded high cellular viability and proliferation ***,hydrogel antimicrobial studies with staphylococcus epidermidis bacteria revealed that the developed hydrogels affected bacterial *** together,these materials show promise for various TE strategies.

摘要：Extrusion-based 3d bioprinting is a direct deposition approach used to create three-dimensional(3d)tissue scaffolds typically comprising *** are hydrated polymer networks that are chemically or physically ***,3d bioprinting is performed in air,despite the hydrated nature of hydrogels and the potential advantage of using a liquid phase to provide cross-linking and otherwise functionalize the *** this work,we print gelatin alginate hydrogels directly into a cross-linking solution of calcium chloride and investigate the influence of nozzle diameter,distance between nozzle and surface,calcium chloride concentration,and extrusion rate on the dimensions of the printed *** hydrogel layer height was generally found to increase with increasing extrusion rate and nozzle distance,according to the increased volume extruded and the available space,*** addition,the hydrogel width was generally found to increase with decreasing nozzle distance and cross-linking concentration corresponding to confinement-induced spreading and low crosslinking regimes,***/height ratios of^1 were generally achieved when the nozzle diameter and distance were comparable above a certain cross-linking *** these relationships,biocompatible 3d multilayer structures were successfully printed directly into calcium chloride cross-linking solution.