摘要：Fast electron-hole recombination issues during titanium dioxide(TiO_(2))photocatalysis limit its application in preventing bacterial infection during bone defect *** this study,TiO_(2)@reduced graphene oxide(rGO)composites were synthesized using a hydrothermal method in which rGO,which possesses very high electrical conductivity,promotes the separation of photoelectron-hole pairs of TiO_(2),thus improving the efficiency of photocatalytic production of reactive oxygen species(ROS).Subsequently,TiO_(2)@rGO composites were introduced into poly-L-lactic acid(PLLA)to prepare bone scaffolds with photocatalytic antibacterial function via selective laser *** results showed that TiO_(2)grew on the surface of rGO and formed a covalent bond connection(Ti-O-C)with rGO.A decreased electrochemical impedance of TiO_(2)@rGO composites was observed,and the transient photocurrent intensity increased from 0.05 to 0.5μA/cm^(2).Analysis of electron spin resonance found that the photocatalytic products of TiO_(2)were·OH and·O^(2-),two kinds of ROS capable of killing bacteria via disrupting the structure of the bacterial membrane in *** experiments showed that the PLLA/TiO_(2)@rGO scaffolds had good antibacterial properties against Escherichia coli and Staphylococcus ***,we report that these scaffolds exhibited both enhanced mechanical properties due to the addition of TiO_(2)@rGO as a reinforcement material and good biocompatibility during cell proliferation.

摘要：The aim of the study was to analyze the histologic and ultrastructural changes after maxillary sinus augmentation with simultaneous implant placement using engineered bone graft *** this study,calcium phosphate cement(CPC)scaffolds combined with goat bone marrow stromal cells(BMSCs)were used to fill goat sinus floor space after maxillary sinus floor elevation with simultaneous implant placement comparing with those not filled any grafted materials and used as *** a healing period of 3 months,the goat maxillary sinus membrane was examined using light microscopy and scanning electronic *** results showed that the connective tissue thickness and the epithelium thickness of mucosa were not statistically significant difference between two *** tissue engineered bone complex might be an ideal graft for the sinus floor elevation and have no influence on the sinus membrane under the histological and ultrastructural observation.

摘要：Regeneration and reconstruction of bone tissue is always a challenge for clinicians due to the uncertainty of bone repair materials in terms of long-term and efficient effects on ***,we propose a novel strategy combining benidipine,an antihypertensive drug and nanoparticles to synergistically promote the healing of bone *** and porous benidipine-loaded magnesium silicate nanoparticles were prepared and validated for their *** nanoparticles were efficiently taken up by preosteoblasts and uniformly distributed around the *** internalization into cells,the nanosystem is degraded by lysosomes,and the effect of promoting osteogenic differentiation is reflected by the continuous release of benidipine,silicon and magnesium *** results clearly evaluated that the nanoflower-like magnesium silicate delivering benidipine tends to be more appropriate for the bone regeneration in preosteoblasts,indicating that it might be a potential approach in guiding bone repair in clinical applications.

摘要：The organized alignment of cells in various tissues plays a significant role in the maintenance of specific *** induce such an alignment,ideal scaffolds should simulate the characteristics and morphologies of natural *** structures that guide cell orientation are used to facilitate tissue regeneration and *** here review how various aligned structures are fabricated,including aligned electrospun nanofibers,aligned porous or channeled structures,micropatterns and combinations thereof,and their application in nerve,skeletal muscle,tendon,and tubular dentin *** future use of aligned structures in tissue engineering is also discussed.

摘要：Mandibular defect occurs more frequently in recent years,and clinical repair operations via bone transplantation are difficult to be further improved due to some intrinsic *** engineering,which is a hot research field of biomedical engineering,provides a new direction for mandibular defect *** the basis and key part of tissue engineering,scaffolds have been widely and deeply studied in regards to the basic theory,as well as the principle of biomaterial,structure,design,and fabrication ***,little research is targeted at tissue regeneration for clinic repair *** mandibular bone has a special structure,rather than uniform and regular structure in existing studies,a methodology based on tissue engineering is proposed for mandibular defect repair in this *** steps regarding scaffold digital design,such as external shape design and internal microstructure design directly based on triangular meshes are discussed in *** analyzing the theoretical model and the measured data from the test parts fabricated by rapid prototyping,the feasibility and effectiveness of the proposed methodology are properly *** works about mechanical and biological improvements need to be done to promote its clinical application in future.

摘要：Previous studies have suggested that the transforming growth factor-β receptor ALK5 is crucial for articular chondrogenesis by bone marrow mesenchymal stem cells. Here, the wild-type ALK5 plasmids were mutated by overlapping extended PCR and transfected into bone marrow mesenchymal stem cells. The knee joint osteoarthritis mouse model was constructed by cutting oft＂ the anterior cruciate ligament and divided into three groups： saline group, bone marrow mesenchymal stem cells and ALK5-transfected bone marrow mesenchymal stem cells group. HE staining showed that the articular cartilage lesions were more serious of saline group compared with that of mesenchymal stem cell group, and this trend was more pronounced as time goes on. Immunohistochemical staining showed that although the expression level of type II collagen in all three groups down-regulated gradually upon time, its expression in ALK5-transfected bone marrow mesenchymal stem cells group was significantly enhanced compared with the other two groups. Micro-CT also suggested that ALK5 transfection of mouse bone marrow mesenchymal stem cells would promote repairing the knee cartilage lesions with arthritis of the mice. Although the osteoarthritis mechanism underlying a variety of factors work together, and the appropriate proportion of ALKS/ALK1 was also emphasized for the treatment of osteoarthritis. This work therefore demonstrated that ALK5 transfection of bone marrow mesenchymal stem cells could be a promising stem cell therapy for repair of cartilage lesions.

摘要：Aim:The correction of nasal tip defects presents many ***’s bilobed flap has been widely used for such repairing defects,but may be complicated by interrupted scars on the nasal *** study evaluates the design principles,results,and advantages of a modified bilobed flap for repairing nasal tip ***:The primary lobe was located between the defect and the cheek,and the second lobe was located in the *** width of the primary lobe was equal to that of the primary *** length of the primary lobe was 10%longer than the distance of the distal defect edge to the pivot point of the *** length of the second lobe was 30%longer than the distance of the distal defect edge to the pivot point of the *** width of the second lobe was 90-100%of that of the primary *** ability to close the defect under minimal tension,the cosmetic appearance,and any complications were ***:This technique was performed in 34 cases;defect size ranged from 0.8 cm×0.9 cm to 1.2 cm×1.8 *** defects were closed under minimal wound tension,all scars were inconspicuous,no obvious complications occurred,and the aesthetic outcomes were considered ***:The modified bilobed flap can provide satisfying outcomes with lower morbidity and inconspicuous *** is simple and suitable for repairing small-to medium-sized defects in the nasal tip.

摘要：In maxillofacial surgery, there is a significant need for the design and fabrication of porous scaffolds with customizable bionic structures and mechanical properties suitable for bone tissue engineering. In this paper, we characterize the porous Ti6Al4V implant, which is one of the most promising and attractive biomedical applications due to the similarity of its modulus to human bones. We describe the mechanical properties of this implant, which we suggest is capable of providing important biological functions for bone tissue regeneration. We characterize a novel bionic design and fabrication process for porous implants. A design concept of “reducing dimensions and designing layer by layer” was used to construct layered slice and rod-connected mesh structure (LSRCMS) implants. Porous LSRCMS implants with different parameters and porosities were fabricated by selective laser melting (SLM). Printed samples were evaluated by microstructure characterization, specific mechanical properties were analyzed by mechanical tests, and finite element analysis was used to digitally calculate the stress characteristics of the LSRCMS under loading forces. Our results show that the samples fabricated by SLM had good structure printing quality with reasonable pore sizes. The porosity, pore size, and strut thickness of manufactured samples ranged from (60.95± 0.27)% to (81.23±0.32)%,(480±28) to (685±31)μm, and (263±28) to (265±28)μm, respectively. The compression results show that the Young’s modulus and the yield strength ranged from (2.23±0.03) to (6.36±0.06) GPa and (21.36±0.42) to (122.85±3.85) MPa, respectively. We also show that the Young’s modulus and yield strength of the LSRCMS samples can be predicted by the Gibson-Ashby model. Further, we prove the structural stability of our novel design by finite element analysis. Our results illustrate that our novel SLM-fabricated porous Ti6Al4V scaffolds based on an LSRCMS are a promising material for bone implants, and are potential

摘要：Nanofibers can mimic natural tissue structure by creating a more suitable environment for cells to grow,prompting a wide application of nanofiber *** this review,we include relevant studies and characterize the effect of nanofibers on mesenchymal stem cells,as well as factors that affect cell adhesion and osteogenic *** hypothesize that the process of bone regeneration in vitro is similar to bone formation and healing in vivo,and the closer nanofibers or nanofibrous scaffolds are to natural bone tissue,the better the bone regeneration process will *** general,cells cultured on nanofibers have a similar gene expression pattern and osteogenic behavior as cells induced by osteogenic supplements in *** involved in cell adhesion(focal adhesion kinase(FAK)),cytoskeletal organization,and osteogenic pathways(transforming growth factor-β(TGF-β)/bone morphogenic protein(BMP),mitogen-activated protein kinase(MAPK),and Wnt)are upregulated *** adhesion and osteogenesis may be influenced by several *** possess certain physical properties including favorable hydrophilicity,porosity,and swelling properties that promote cell adhesion and ***,nanofiber stiffness plays a vital role in cell fate,as cell recruitment for osteogenesis tends to be better on stiffer scaffolds,with associated signaling pathways of integrin and Yes-associated protein(YAP)/transcriptional co-activator with PDZ-binding motif(TAZ).Also,hierarchically aligned nanofibers,as well as their combination with functional additives(growth factors,HA particles,etc.),contribute to osteogenesis and bone *** summary,previous studies have indicated that upon sensing the stiffness of the nanofibrous environment as well as its other characteristics,stem cells change their shape and tension accordingly,regulating downstream pathways followed by adhesion to nanofibers to contribute to ***,additional experiments are needed to id

摘要：设计和制备具有优异防污能力的可注射防粘连材料对预防手术后组织和器官的粘连具有重要的意义.在此,我们将含有羟基的氨基酸衍生物引入水凝胶的制备中,通过N-丙烯酰丝氨酸(ASer)的自由基聚合制备了一种新型的氢键交联水凝胶(PASer).结果发现一个甲基取代基的存在会对分子间氢键相互作用产生明显的影响:与聚(N-丙烯酰苏氨酸)(PAThr)水凝胶相比,PASer水凝胶具有较低的成胶浓度和增强的力学性能.值得一提的是,亲水性羟基使PASer水凝胶能够有效抵抗蛋白质吸附和细胞粘附.PASer水凝胶具有优异的力学性能、可注射性、自融合性、良好的生物相容性和适宜的体内停留时间,符合临床对术后抗粘连材料的要求.体内研究实验结果表明,PASer水凝胶在建立的小鼠腹壁缺损模型中可以有效预防术后腹膜粘连发生.