摘要：Due to a worldwide focus on sustainable materials for human health and economy services, more and more natural renewable biomass are regarded as promising materials that could replace synthetic polymers and reduce global dependence on petroleum resources. Cellulose is known as the most abundant renewable polymer in nature, varieties of cellulose-based products have been developed and have gained growing interest in recent years. In this review, a kind of water-soluble cellulose derivative, i.e., sodium cellulose sulfate (NaCS) is introduced. Details about NaCS's physicochemical properties like solubility, biocompatibility, biodegradability, degree of substitution, etc. are systematically elaborated. And promising applications of NaCS used as biomaterials for microcarriers' designing, such as microcell- carriers, micro-drug-carriers, etc., are presented.

摘要：The immune response after implantation of a biomaterial may shorten the functional life of the implant,depending on the degree of the *** this study,we used a polyacrylamide-alginate(PAAm-Alg)hydrogel,which has been previously characterized as a biocompatible material and shown to enhance regeneration of cartilage in vivo,along with a graphiteenhanced hydrogel(PAAm-Alg-G)as a non-biocompatible counterpart,to evaluate macrophage attachment and polarization to pro-or anti-inflammatory *** performance of each biomaterial in the presence of fibroblasts and chondrocytes was validated by an in vitro model which demonstrated modulation of the foreign-body response.A blend of 5%gelatin methacryloyl and 0.1%methacrylated hyaluronic acid was optimized to mimic the extracellular matrix(ECM)and support cell viability,proliferation,migration,and functionality at an initial concentration of 3.25×10^(5) cells/*** PAAm-Alg-G hydrogel localized in the simulated ECM showed cytotoxic and genotoxic effects for both fibroblasts and chondrocytes,while exhibiting a proliferative effect on macrophages with elevated immune *** M1/M2 ratio was 0.73 for PAAm-Alg hydrogel but 2.64 for PAAm-Alg-G,leading to significant M1 dominance(p0.05).The interleukin-6(IL-6)concentration secreted in the presence of PAAm-Alg hydrogel(4.58 pg/mL)significantly decreased(p<0.0001)on day 13,while the increase(p<0.0001)in interleukin-10(IL-10)concentration(120.73 pg/mL)confirmed the switch from a pro-inflammatory to an anti-inflammatory *** immune responses by developing a simplistic yet powerful three-dimensional in vitro model provides advantages in preparing for clinical use of biomaterials.

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：Three-dimensional(3D)organoids derived from pluripotent or adult tissue stem cells seem to possess excellent potential for studying development and disease mechanisms alongside having a myriad of applications in regenerative ***,lack of precise architectures and large-scale tissue sizes are some of the key limitations of current organoid technologies.3D bioprinting of organoids has recently emerged to address some of these *** this review,we discuss 3D bioprinting with respect to the use of bioinks and bioprinting methods and highlight recent studies that have shown success in bioprinting of stem cells and *** also summarize the use of several vascularization strategies for the bioprinted organoids,that are critical for a complex tissue *** fully realize the translational applications of organoids in disease modeling and regenerative medicine,these areas in 3D bioprinting need to be appropriately harnessed and channelized.

摘要：In this paper,we present a 3D printed tumor spheroidal model suitable for drug *** model is based on a hydroxyethyl cellulose/alginate/gelatin(HCSG)composite biomaterial that has three distinct properties:(1)the HCSG is similar to the commercial basement membrane extract in Ki67,MUC1,and PARP1 expressions of MCF-7 cells for embedding culture;(2)the HCSG is printable at room temperature;and(3)the HCSG can be large-scale manufactured at an ultralow *** printed a 3D MCF-7 spheroid model with HCSG and characterized it in terms of cell viability,spheroid size,key protein expression,and mitochondrial metabolic *** used the 3D MCF-7 spheroid model to evaluate the anti-breast cancer activity of 13 amino acid-based flavone phosphoramidates and found that the alanine structure induced a stronger drug resistance,whereas phenylalanine hardly caused drug resistance in the MCF-7 *** is the first time that 3D bioprinting technology has been used in a structure–activity relationship study.

摘要：The keratoprosthesis(KPro;artificial cornea)is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain *** main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating *** current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial *** a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells,modification of keratoprosthesis to support cornea cells remains *** of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials,but also more importantly continuous and stable cornea cells can prevent the destruction of *** necrosis of stroma and spontaneous extrusion of the device,allow for maintenance of a precorneal tear layer,and play the role of ensuring a good optical surface and resisting bacterial *** a result,improvement in corneal cells has been the main aim of several recent investigations;some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea *** purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

摘要：Magnesium alloys have shown prospective applications as a new biodegradable metal within bone. To garantee the longterm biocompatibility, a Mg-Zn-Ca alloy,composing of essential elements for human, was prepared and its feasibility for orthopedic applications was investigated. The in vitro and in vivo corrosion of Mg-Zn-Ca alloy as well as the biocompatibility were studied. The in vitro corrosion tests in five kinds of physiological solutions showed that the corrosion rates and corrosion morphologies of the alloy were strongly influenced by the solution used. The addition of serum in Hank’s and MEM significantly slowed down the corrosion rate and improved the corrosion uniformity of the alloy. The corrosion rate decreased with increasing serum *** alloy showed the slowest corrosion rate as well as homogeneous corrosion morphology in MEM＋10%FBS. Both the indirect and direct cell experiments indicated good cytocompatibility of the extruded Mg-Zn-Ca alloy. In vivo, we observed a gradual degradation process from the surface of extruded Mg-Zn-Ca alloy and only 40% in volume of implant was left after 4 weeks implantation in medullary cavities of mice. The micro-CT and histological analyses revealed its good biocompatibility with peri-implant new bone formation and increasing cortical bone thickness with increasing implantation period. This study showed that the extruded MgZn-Ca alloy provided sufficient biocompatibility for orthopedic application, though the in vivo corrosion rate should be further reduced for clinical use.

摘要：Many cellular models have been used to investigate bone substitutes including coralderived hydroxylapatite (HA). The aim of this study was to verify whether a new cellular model represented by Saos-eGFP cells can be used to test biomaterials by in vitro assays. SaoseGFP cells which express the enhanced Green Fluorescent Protein (eGFP), were derived from the osteoblast-like cell line Saos-2. To this purpose Saos-eGFP cells were employed to investigate the in-vitro bioactivity of a well characterized coral-derived HA biomaterial, in block and granule forms. This engineered cell line, by evaluating the emitted fluorescence, allowed us to assay (i) cell adhesion, (ii) cell proliferation and (iii) colony capability. Electron microscopy analysis was employed to evaluate the (iv) morphology of cells seeded on the biomaterial surface. (v) Histological analysis of the bone grown after scaffold implantation was carried out in specimens from two clinical cases. Saos-eGFP cells indicate, as established before, that the coralline-HA biomaterials has a good in vitro cytocompatibility when tested with human osteoblast-like cells. Some differences in proliferation activity was detected for the two different forms assayed. Cytocompatibility data from in vitro analyses were confirmed by in vivo behaviour of biomaterials. Our tests suggest that the engineered cell line Saos-eGFP represents a suitable in vitro mode for studying the biocompatibility, the cell adhesion, spreading and proliferation on biomaterials developed for clinical applications. The main advantages of this cellular model are (i) less time consuming and (ii) a reduced cost of the experiments.

摘要：Tissue engineering is an interdisciplinary field promising new therapeutic means for replacing lost or severely damaged tissues or organs. However, the fabrication of complex engineered tissues has been hampered due to the lack of vascularization to provide sufficient blood supply after implantation. In this article, we propose using rapid prototyping technology to prefabricate a scaffold with an inside hollowed vascular system including an arterial end, a venous end and capillary networks between them. The scaffold will be ''printed'' layer by layer. When printing every layer, a ''low-melting point'' material will be used to form a blood vessel network and a tissue-specific material will be used outside it. Hereafter the ‘low-melting point’ material will be evacuated by vaporization to ensure a hollowed vessel network. Then the inside hollowed capillary network can be endothelialized by using autologous endothelial cells in a cycling bioreactor while the outside material can be embedded with tissue-special cells. In the end, the new vascularized autologous grafts could be transferred to the defect site by using microsurgical techniques to connect the grafts with the host artery and vein. The strategy would facilitate construction of complex tissue engineering if the hypothesis proved to be practical.