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    18 January 2018, Volume 22 Issue 2 Previous Issue    Next Issue
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    A modified working tube can reduce bone cement leakage in the treatment of osteoporotic vertebral compression fracture
    Zhang Zhi-qiang, Yang Jian-dong, Feng Xin-min, Wang Yong-xiang, Tao Yu-ping, Cai Jun, Zhang Liang
    2018, 22 (2):  165-170.  doi: 10.3969/j.issn.2095-4344.0001
    Abstract ( 503 )   PDF (1159KB) ( 190 )   Save
    BACKGROUND: Vertebroplasty is an effective treatment for osteoporotic vertebral compression fractures (OVCF), but it is nagged by bone cement leakage.
    OBJECTIVE: To summarize the clinical outcome of modified self-making working tube in percutaneous vertebroplasty (PVP) for treatment of thoracolumbar OVCF.
    METHODS: Modified PVP working tube was designed to have a lateral gap at the sleeve tail, which could control the cement diffuse direction though rotating the working tube. Totally 121 thoracolumbar OVCF patients were enrolled, including 49 males and 72 females, aged 62-90 years, and then divided into two groups: 59 patients were treated with modified PVP in test group, and the other 62 patients experienced conventional PVP in control group. In the test group, a lateral gap instead of the conventional gap at the sleeve tail was made to control the direction of bone cement injection by rotating the sleeve. The visual analogue scale scores were compared before and after operation; radiographic examination was performed to detect bone cement leakage at 1 day postoperatively.
    RESULTS AND CONCLUSION: There were significant differences between the preoperative and postoperative visual analogue scale scores in the two groups (P < 0.05), but there was no significant difference between the two groups. There were 3 cases of bone cement leakage in the test group and 10 cases of bone cement leakage in the control group. Modified PVP working tube had significant lower rate of bone cement leakage than traditional PVP (14.9% vs. 4.6%, P < 0.05). Therefore, the modified PVP working tube is an effective tool to decrease the incidence of bone cement leakage in the treatment of thoracolumbar OVCF.
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    Effects of percutaneous vertebroplasty with different bone cement volumes on the adjacent intervertebral disc in a rabbit model of osteoporosis  
    Zhang Han-xiang, Fan Hua-hua, Cai Xiao-jun
    2018, 22 (2):  171-177.  doi: 10.3969/j.issn.2095-4344.0002
    Abstract ( 386 )   PDF (3055KB) ( 206 )   Save
    BACKGROUND: With the development of clinical practices, some complications of vertebroplasty are gradually highlighted. Considering the thermal reaction, toxicity and space-occupying filling of bone cement, vertebroplasty with bone cement injection is likely to cause some impacts on the surrounding vertebrae, especially the adjacent ones. However, little is reported on the effect of different volumes of bone cement on degeneration of the adjacent vertebrae.
    OBJECTIVE: To determine the effects of different bone cement volumes in percutaneous vertebroplasty on adjacent intervertebral discs in a rabbit model of osteoporosis.
    METHODS: Thirty 5-month-old New Zealand rabbits were randomly assigned into five groups: sham, iohexol, low-dose bone cement, middle-dose bone cement and high-dose bone cement groups. Osteoporosis models were established by ovariectomy combined with glucocorticoid injection. After modeling, sham puncture at the fifth lumbar vertebrae was done in the sham group, and true puncture at the fifth lumber vertebra was done in the iohexol group followed by injection with 0.2 mL of iohexol. Different volumes of bone cement (0.1, 0.2, 0.3 mL) were injected in the low-, middle- and high-dose bone cement groups, respectively. After 12 weeks, rabbits in these three groups were killed to take the intact L4-5 segments that were divided into two parts: one for TUNEL staining to observe cell apoptosis and to calculate apoptotic index, and the other for real-time PCR detection of relative expression of interleukin-1, type II collagen and matrix metalloproteinase-7.
    RESULTS AND CONCLUSION: The cell apoptosis index in the low-, middle- and high-dose bone cement groups were significantly different from that in the sham and iohexol groups, but there was no significant difference among three bone cement groups. The relative expression of interleukin-1 mRNA showed a significant difference between the high-dose group and sham group. The relative expression of type II collagen and matrix metalloproteinase-7 in the three bone cement groups was significantly different from that in the sham and iohexol groups, and the expression in the high-dose bone cement group was also significantly different from that in the low- and middle-dose bone cement groups. To conclude, after percutaneous vertebroplasty, injected bone cement certainly impacts the adjacent vertebrae in the rabbit model of osteoporosis, but not in a dose-dependent manner. Moreover, a dramatic aggravation of degeneration of the adjacent vertebrae is developed when high-dose bone cement is injected.
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    Treatment of Sanders type III fracture of the calcaneus with polymethylmethacrylate bone cement: a biomechanical study 
    Guan Zhi-hai, Wang Qin-ye, Chang Xiao-bo, Ning Bo, Luo Ya-ping
    2018, 22 (2):  178-182.  doi: 10.3969/j.issn.2095-4344.0003
    Abstract ( 312 )   PDF (1286KB) ( 147 )   Save
    BACKGROUND: Polymethylmethacrylate (PMMA), commonly known as bone cement, has been widely used in the orthopedic surgery. It ensures the immediate stability of prosthesis and the minimal micromotion at the cement-bone interface, allowing early weight-bearing after surgery.
    OBJECTIVE: To investigate the biomechanical performance of Sanders type III fracture of the calcaneus by using PMMA bone cement as a treatment.
    METHODS: Eight adult cadaveric ankle and calcaneus specimens were selected and served as normal controls after detection of biomechanical properties. Another eight specimens were collected and randomized into experimental group and control group to make a model of Sanders type III fracture in the calcaneus. In the experimental group, PMMA bone cement was injected into the defect area. In the control group, the artificial bone was implanted in the defect area and a steel plate was used to fix the lateral calcaneus. Biomechanical properties of the specimens in the experimental and control group were detected.
    RESULTS AND CONCLUSION: (1) Strain and stress of the calcaneus: The stress distribution of the calcaneus in the normal control group was consistent with that in the experimental group, and there was no significant difference between the two groups. The stress of the calcaneus in the experimental group was similar to that in the control group with no significant difference. (2) Displacement and axial stiffness of the calcaneus: Compared with the normal control group, the calcaneal displacement in the experimental group only decreased slightly, and there was no significant difference between the two groups, and likewise, the calcaneal displacement in the control group increased slightly. In the experimental group, the axial compression strength was (21.98±1.88) MPa and the axial compression stiffness was (1 633±150) N/mm. Therefore, there was no significant difference between the experimental group and the normal control group (P > 0.05). (3) Contact strength of the subtalar joint: Fractures basically recovered with good outcomes after PMMA bone cement injection. To conclude, by using PMMA bone cement in the treatment of calcaneus fractures, the scientific validity and clinical utility can be ensured.
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    Construction of a three-dimensional finite element model of pulp-exposed maxillary premolar with wedge-shaped defect restored by fiber post
    Mo Si-su, Bao Wei, Shen Qing-yi
    2018, 22 (2):  183-188.  doi: 10.3969/j.issn.2095-4344.0004
    Abstract ( 376 )   PDF (1065KB) ( 179 )   Save
    BACKGROUND: To date, there is no report on the successful construction of a three-dimensional finite element model of maxillary premolar with wedge-shaped defect restored by fiber post.
    OBJECTIVE: To establish the three-dimensional finite element model of maxillary premolar with wedge-shaped defect restored by fiber post.
    METHODS: Micro-CT was used to obtain imaging information of the human maxillary first premolar sample. Then Mimics, Geomagic and Hypermesh were used to establish a clear-structured three-dimensional finite element model of pulp-exposed maxillary premolar with wedge-shaped defect restored by fiber post.
    RESULTS AND CONCLUSION: The three-dimensional finite element model of normal maxillary premolar had 180 119 units and 33 289 nodes. Compared with the real subject, the three-dimensional finite element model of maxillary premolar with wedge-shaped defect restored by fiber post had vivid appearance, good image quality and accurate grid partitioning with 237 496 units and 43 965 nodes in total, which could obtain good results in the aspects of geometry, boundary constraint and mechanical compatibility. Moreover, it could better simulate the mechanical stress distribution of diseased teeth under occlusion to further confirm the magnitude and distribution of forces, thereby providing a better basis for future biomechanical studies. 
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    Preparation and biological properties of TiN/Ag composite coating on pure titanium surface 
    Ma Ming, Wan Rong-xin, Lv Xiao-fei, Chu Shan-shan, Li Li-jun, Gu Han-qing, Peng Cheng
    2018, 22 (2):  189-195.  doi: 10.3969/j.issn.2095-4344.0005
    Abstract ( 382 )   PDF (2836KB) ( 162 )   Save
    BACKGROUND: It is of vital importance to fabricate an interface on the titanium implant surface which can promote early cell adhesion, proliferation, and differentiation, and exert better antibacterial effects with no cytotoxicity.
    OBJECTIVE: To prepare a TiN/Ag composite coating on the surface of pure titanium implant, and to explore its antibacterial properties and effects on MC3T3-E1 biobehaviors.
    METHODS: Acid etching blasting and multi-arc ion plating were adopted to prepare TiN/Ag composite coating on the smooth surface of pure titanium. Then, MC3T3-E1 cells that grew well were inoculated onto pure titanium plate, sandblasted and acid-etched titanium plate, and TiN/Ag-coated titanium plate. Twenty-four hours later, cell adhesion and viability were observed under confocal laser scanning microscope, and cell morphology was observed under scanning electron microscope. Cell counting kit-8 was used to detect cell proliferation and cytotoxicity at 24, 48, 72 hours after inoculation. In addition, Staphylococus aureus solution was dropped onto the smooth titanium plated, acid-etched and sandblasted titanium and TiN/Ag-coated titanium plate, and the growth of bacteria was observed by the laser confocal scanning microscope at 16 hours.
    RESULTS AND CONCLUSION: Under the confocal laser scanning microscope, spindle cells with bipolar or three poles were observed on the smooth titanium surface, and there was less F-actin and filopodia expression; cells on the TiN/Ag-coated titanium surface and sandblasted and acid-etched titanium surface were scattered with a large amount of interconnected filopodia that were fully stretched and adhered to the titanium surface, highly expressed F-actin was detected, and actin fibers were thickened. Under the scanning electron microscope, the cells on the smooth titanium surface were not fully adhered and stretched, and those on the TiN/Ag-coated titanium surface or the sandblasted and acid-etched titanium surface exhibited better adhesion and extension. Findings from the cell counting kit-8 showed that after 72 hours of inoculation, the cells on the smooth titanium surface grew well, with cytotoxicity level 1. In addition, Staphylococus aureus grew well on the smooth titanium surface under the confocal laser scanning microscope, while a large amount of Staphylococus aureus died on the TiN/Ag-coated titanium surface or on the sandblasted and acid-etched titanium surface. These findings indicated that TiN/Ag coating has good biocompatibility and antibacterial properties. 
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    Biomechanical finite element analysis on the bone interface of posterior mandibular area under different setting forces after inclined implantation with angled abutment
    Liu Li-ping, Lv Xiao-fei, Deng Shu, Peng Cheng
    2018, 22 (2):  196-203.  doi: 10.3969/j.issn.2095-4344.0006
    Abstract ( 393 )   PDF (5808KB) ( 203 )   Save
    BACKGROUND: Single tooth loss at posterior mandibular area is difficult to complete regularly axial implantation under limited conditions. Concerning this problem, some scholars employ the skill of tilted implantation with abutment angulations to restore it. However, the security study of this design has been limited until now.
    OBJECTIVE: To provide theoretical evidence for tilted implantation in the posterior mandibular area, and to make a biomechanical analysis on bone-implant interface after titled implantation under the same dynamic force stress.
    METHODS: First, restoration models of implant crown at different tilting angles in posterior mandibular area were built and optimized using the software CBCT and DICOM. Then dynamic force stress was applied in chewing cycles of the crown model. Finally, the stress-strain analysis of bone-implant interface was made by utilizing the three-dimensional finite element software Ansys.
    RESULTS AND CONCLUSION: (1) When the dental implant in the axis implantation was tilted to the lingual side at 5° or 10°, the maximum stress and strain values at the bone interface were 53.8 MPa and 2 671, respectively, under three loading conditions: the force during the chewing cycle was given vertical to the implant, toward the lingual side from the buccal side at 45° with the long axis of the tooth, and toward the buccal side from the lingual side at 45° with the long axis of the tooth. (2) When the implant inclined to the lingual side at a 15° angle, the rear edge of the implant was close to the interface between the cortical and cancellous bone, and the stress and strain values were bigger than those at any other implantation angle. (3) When the implant inclined to the lingual side at a 20° angle, the rear edge of the implant was beyond the interface between the cortical and cancellous bone, and contacted with the cortical bone that provided a support for the rear part of the implant. The stress and strain values on the bone interface were both reduced. The stress was concentrated in the cortex around the neck of the implant, and reduced a lot in the cancellous bone. The maximum strain value appeared at the contact site between the bone interface and the implant neck or rear part. It is concluded that in posterior mandibular area, the dental implant can be implanted at a < 10° linguoclination angle.
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    Platelet-rich fibrin combined with tooth ash promotes bone repair
    Wang De-li, Xu Wen-xiu, Lin Na, Wang Hai-yan, Shi Yi, Yu Xue-gang, Li Qiao-ling, Zhou Yang,Luan Hai-rong
    2018, 22 (2):  204-209.  doi: 10.3969/j.issn.2095-4344.0007
    Abstract ( 352 )   PDF (5905KB) ( 196 )   Save
    BACKGROUND: The tooth ash can be used as a scaffold for bone tissue growth and provide calcium and phosphorus components during bone regeneration. Platelet-rich plasma can promote the soft and hard tissue regeneration. However, either of them has its shortcomings.
    OBJECTIVE: To investigate the effect of platelet-rich plasma combined with tooth ash in repairing skull bone defects.
    METHODS: Nine healthy rabbits were selected to make bone defects on both sides of the skull. Rabbit platelet-rich plasma combined with tooth ash was implanted into the skull defect on the left side as experimental group, while rabbit platelet-rich plasma was implanted into the skull defect on the right side as control group. Skull samples were taken out at 4, 6, 8 weeks after implantation for soft X-ray detection, hematoxylin-eosin staining and modified Gomori staining.
    RESULTS AND CONCLUSION: (1) Soft X-ray: The trabecular bone area of the experimental group was larger than that of the control group at 6 and 8 weeks after implantation (P < 0.05 or P < 0.01). (2) Hematoxylin-eosin staining: With the duration of implantation, newly formed fibers with bone structure gradually reduced at the defect sites in both groups, and there was a orderly layered arrangement in the bone structure and increased calcification. Compared with the control group, relatively higher new bone maturity, better bone trabecular arrangement and more osteoblasts were observed in the experimental group. (3) Modified Gomori staining: With the prolongation of implantation time, the new bone became mature gradually in the two groups, and the bone maturity in the experimental group was higher than that in the control group. To conclude, platelet-rich fibrin combined with tooth ash is better to promote bone defect repair. 
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    Recombinant human bone morphogenetic protein 2/poly(lactic-co-glycolic acid) copolymer microspheres with different particle sizes: preparation and release performance in vivo and in vitro  
    Bao Yu-cheng, Wang Yong, Zhang Wen-long, Xie Yi, Yu Mei-li
    2018, 22 (2):  210-215.  doi: 10.3969/j.issn.2095-4344.0008
    Abstract ( 375 )   PDF (1573KB) ( 202 )   Save
    BACKGROUND: The technology of biodegradable materials covering growth factors can be used to make sustained-release microspheres, which provides the feasibility for the efficient utilization of growth factors.
    OBJECTIVE: To prepare nano/micron-sized spheres using recombinant human bone morphogenetic protein 2/poly(lactic-co-glycolic acid) (rhBMP-2/PLGA) copolymer and to compare their release behaviors by in vivo and in vitro release experiments.
    METHODS: The rhBMP-2/PLGA nano/micron-sized spheres were prepared by emulsion solvent evaporation method to control the rate of pulp mixing. (1) In vitro release experiment: Prepared nano/micron-sized spheres were dissolved in PBS for 70 days, and then ELISA method was used to detect the rhBMP-2 concentration in the supernatant at different time. (2) In vivo release experiment: Forty-four New Zealand rabbits were divided into two groups, and rhBMP-2/PLGA nano/micron-sized spheres were respectively implanted into trochanteric defects. The concentration of rhBMP-2 in the defect site was detected by ELISA within 70 days after implantation.
    RESULTS AND CONCLUSION: In vitro sustained release experiment: There was a sudden release of nanospheres in the former 3 days, and the cumulative release nearly reached 41%, followed by a steady and slow release, and then the cumulative release was up to approximately 83% at 70 days. The initial release of micron-sized spheres was less than that of nanospheres, and the cumulative release was about 20% within the former 3 days and reached to 70% at 70 days. In vivo sustained release test: There was a sudden release of the nanospheres, the cumulative release was nearly 35%, followed by a steady and slow release, and then the cumulative release was up to approximately 72% at 70 days. The initial release of micron-sized spheres was less than that of nanospheres, and the cumulative release was about 21% in the former 3 days and increased to about 63% at 70 days. In both in vivo and in vitro release experiments, the release duration of micron-sized spheres was longer than that of nanospheres in the former 3 days. To conclude, the release time of rhBMP-2/PLGA micron-sized spheres fulfills the need of bone growth cycle, therefore, rhBMP-2/PLGA micron-sized spheres are more favorable than rhBMP-2/PLGA nanospheres for bone defect repair in clinical practice.
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    In vivo and in vitro hemostatic effects of composite collagen sponge
    Jin Shao-feng, Qi Hui, Shu Xiong, Jie Yong-sheng, Zheng Rui, Chen Lei, Sun Lei
    2018, 22 (2):  216-221.  doi: 10.3969/j.issn.2095-4344.0009
    Abstract ( 483 )   PDF (1548KB) ( 202 )   Save
    BACKGROUND: Collagen has good hemostatic effect, but the single collagen hemostatic material has no ideal hemostatic efficiency due to limited water absorption capacity and poor blood concentration effect.
    OBJECTIVE: To observe the hemostatic effect of composite collagen sponge in vivo and in vitro.
    METHODS: Collagen, sponge and calcium chloride were used as raw materials to prepare composite collagen sponge. (1) Cell toxicity test: Mouse L929 cells were cultured using composite collagen sponge extract, phenol solution and cell culture medium for 2, 4, 7 days. Then, cell proliferation was detected by MTT to evaluate cell toxicity. (2) The relationship between the material and the whole blood: The relationship between the materials and the whole blood was observed by scanning electron microscope among composite collagen sponge, imported hemostatic materials and domestic hemostatic materials, following dripping the rabbit's anticoagulant blood onto the material surface. (3) In vitro coagulation activity: Blood Clotting Index was used to detect the effect of coagulation among composite collagen sponge, imported hemostatic materials and domestic hemostatic materials, following dripping the rabbit's anticoagulant blood onto the material surface. (4) Liver leaves from 18 rabbits were drilled, and then randomly divided into three groups covered with composite collagen sponge, imported hemostatic materials and domestic hemostatic materials, respectively. Bleeding time and bleeding volume were measured.
    RESULTS AND CONCLUSION: (1) The cytotoxicity of composite collagen sponge was qualified as grade 1. (2) Compared with imported and domestic hemostatic materials, composite collagen sponge was conducive to blood water absorption but also to the further network hemoglobin and platelet clot formation, and the pores alternately extended to the interior to form the alternating complex sponge. (3) The blood clotting index of composite collagen sponge was significantly lower than that of imported and domestic hemostatic materials (P < 0.05). (4) The bleeding time and bleeding volume of composite collagen sponge were significantly lower than those of imported and domestic hemostatic materials (P < 0.05). Overall, the composite collagen sponge as a hemostatic material has good hemostatic effect and biocompatibility.
    中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程
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    Mitochondria-mediated synthesis of gold-silver alloy nanoparticles
    Meng Biao, Chen Wei-yi, Zhang Yi-xia, Wen Xu-dong, Li Kai
    2018, 22 (2):  222-227.  doi: 10.3969/j.issn.2095-4344.0010
    Abstract ( 283 )   PDF (1176KB) ( 143 )   Save
    BACKGROUND: Due to its strong catalytic activity and selective catalytic oxidation, gold-silver bimetallic nanoparticles have potential applications in biomedicine, drug delivery and electrochemical analysis.
    OBJECTIVE: To prepare the gold-silver alloy nanoparticles using mitochondria in animal cells as templates.
    METHODS: Separating mitochondria from the fish liver: 1 mL of mitochondrial mother liquor was added into 1 mL of alkaline HAuCl4 solution (10 mmol/L) and shaken; then, 1 mL of AgNO3 solution (10 mmol/L) was added, and the mixture was reacted in an electromagnetic stirrer for 20-30 hours until the color of the reaction solution was changed from colorless to purple, which indicated that gold and silver alloy nanoparticles were successfully obtained; finally, the characterization  of the nanoparticles was analyzed. (1) Cytotoxicity test: gold-silver alloy nanoparticles atdifferent concentrations (0, 25, 50, 75, 100, 125, 150 mg/L) were added into gastric cancer cells. After 48 hours of culture, the proliferation of cells (absorbance value) was detected by MTT assay. (2) Stability evaluation: 1 mL of gold-silver alloy nanoparticles at different concentrations (0, 25, 50, 75, 100, 125, 150 mg/L) were placed into glass reaction flasks and then, 0.2 mL of ultrapure water was added in portions following by shaking. After addition of the ultra-pure water, ultraviolet-visible spectrum was used to analyze the characterization of the solution.
    RESULTS AND CONCLUSION: The gold-silver alloy nanoparticles were spherically distributed and confirmed to have an alloy structure with the average particle size of 20-30 nm, and presented to have the advantages of simple structure, good crystallinity, and active groups such as hydroxyl and carbonyl groups on the surface. MTT results showed that the gold-silver alloy nanoparticles at the mass concentration of < 150 mg/L had no obvious cytotoxicity. The characteristic absorption peak with the largest intensity was positively correlated with the concentration of gold-silver alloy nanoparticles. To conclude, the gold-silver alloy nanoparticles have good cytocompatibility and stability in vitro.
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    Injectable nano-hydroxyapatite/chitosan composite scaffolds combined with bone marrow mesenchymal stem cells and bone morphogenetic protein 2 for bone defect repair in vitro  
    Liu Guang-tao, Gao Feng, Xu Jun, Zheng Wei-zhuo, Lin Xiao-zong, Zhou Chang-lin, Guo Ya-shan, Tian Jun
    2018, 22 (2):  228-233.  doi: 10.3969/j.issn.2095-4344.0011
    Abstract ( 372 )   PDF (2761KB) ( 179 )   Save
    BACKGROUND: Bone morphogenetic protein 2 (BMP-2) has a strong ability to induce and promote the osteogenic differentiation of mesenchymal stem cells.
    OBJECTIVE: To evaluate the BMP-2 effect on the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) on an injectable nano-hydroxyapatite/chitosan (nHA/CS) composite scaffold.
    METHODS: (1) Experiment 1: Passage 3 BMSCs were divided into two groups and cultured with the nHA/CS scaffold or cultured alone. Cell counting kit-8 was used to detect cell proliferation at 1, 3, 5, 7, 14 days of culture. (2) Experiment 2: Passage 3 BMSCs were seeded onto the nHA/CS scaffold and cultured in culture medium containing BMP-2 or not. Alkaline phosphatase activity in cells was detected at 3, 6, 9, 12, 15 days of culture. Cell counting kit-8 was used to detect cell proliferation at 1, 3, 5, 7, 14 days of culture. Alizarin red staining was used to observe the osteogenic differentiation of cells at 1 and 2 weeks of culture.
    RESULTS AND CONCLUSION: (1) Experiment 1: With the prolongation of culture time, the absorbance values in the two groups were gradually increased, but there was no significant difference between the two groups. At 7 days of culture, the BMSCs adhered tightly to the scaffold surface. (2) Experiment 2: With the prolongation of culture time, the alkaline phosphatase activities in the two groups were gradually increased, and moreover, the alkaline phosphatase activity in the experimental group was higher than that in the control group at different culture time (P < 0.05). The absorbance values in the two groups were also gradually increased, and the value in the experimental group was higher than that in the control group at different culture time (P < 0.05). At 1 and 2 weeks of culture, the number of calcified nodules was higher in the experimental group than the control group. To conclude, BMP-2 has a promotion role in the proliferation and differentiation of BMSCs cultured on the injectable nHA/CS scaffold.
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    Preparation of a poly(3-hydroxybutyrate-4-hydroxybutyrate)/polyvinyl alcohol composite scaffold by coaxial electrospinning and its biocompatibility
    Liu Qin, Ye Chuan, Zhang Jun-biao, He Zhi-xu, Cui Dong-bing, Yang Yan, Li Jing, Zhu Ting-ting, Chen Jiao, Ma Min-xian
    2018, 22 (2):  234-240.  doi: 10.3969/j.issn.2095-4344.0012
    Abstract ( 365 )   PDF (6145KB) ( 156 )   Save
    BACKGROUND: Poly(3-hydroxybutyrate-4-hydroxybutyrate) (P3HB4HB) is a kind of polymer material that can be completely degraded, has good film-forming property and physical properties, but has poor hydrophilicity.
    OBJECTIVE: To prepare P3HB4HB/polyvinyl alcohol (PVA) coaxial electrospun scaffolds, and to investigate the physical properties and biocompatibility of scaffolds in vitro.
    METHODS: We prepared P3HB4HB electrospun scaffold, PVA electrospun scaffold and P3HB4HB/PVA coaxial electrospun composite scaffold, and then detected the morphology and characterization, contact angle, and tensile mechanical properties of the scaffolds. Passage 4 bone marrow mesenchymal stem cells (BMSCs) from Sprague-Dawley rats were seeded on the three kinds of scaffolds. Cell adhesion rate was detected at 1, 3, 6 hours after seeding; cell proliferation was detect at 1, 3, 5, 7 days after seeding; and cell viability was observed fluorescence staining at 7 days after seeding. Passage 4 BMSCs were seeded onto the three kinds of scaffolds followed by 14 days of osteogenic and chondrogenic induction. Then, alizarin red staining and toluidine blue staining were used to verify BMSCs differentiation potentials.
    RESULTS AND CONCLUSION: (1) Scaffold morphology: Under the scanning electron microscope, the structure of the scaffold in each group was a three-dimensional interconnected network. The fiber diameters of P3HB4HB electrospun scaffold and P3HB4HB/PVA electrospun scaffold were homogeneous and ordered. The P3HB4HB/PVA scaffold showed an obvious core-shell structure under the transmission electron microscope. (2) Scaffold characterization: The tensile strength, tensile modulus and maximum stress of the P3HB4HB and P3HB4HB/PVA scaffolds were significantly higher than those of the PVA electrospun scaffold (P < 0.05). The contact angle of the P3HB4HB/PVA composite scaffold was less than 90°. (3) Cell adhesion rate was ranked as follows: PVA electrospun scaffold group > P3HB4HB/PVA composite scaffold group > P3HB4HB electrospun scaffold group (P < 0.05). (4) Proliferation and activity of cells: The cell proliferation of the P3HB4HB/PVA composite scaffold group was faster than that of the other two groups at 5 and 7 days (P < 0.05). There were more viable cells on the PVA electrospun scaffold and composite scaffold than on the P3HB4HB electrospun scaffold. (5) Cell differentiation: Osteogenesis and cartilage specific staining of the composite scaffold were stronger than those in the other two groups. Overall, the P3HB4HB/PVA coaxial electrospun scaffold has good biocompatibility and a certain mechanical strength.
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    Biocompatibility of a novel calcium-magnesium phosphate composite cement in dentistry
    Shen Qing-yi, Li Guo-qiang, Li Kai
    2018, 22 (2):  241-247.  doi: 10.3969/j.issn.2095-4344.0013
    Abstract ( 404 )   PDF (1113KB) ( 203 )   Save
    BACKGROUND: In our preliminary experiments, calcium phosphate cement, magnesium phosphate cement, calcium silicate and bismuth were mixed to manufacture a novel inorganic composite material, which would be used to repair furcal perforation. This novel composite cement has been confirmed to have excellent physiochemical and mechanical properties.
    OBJECTIVE: To study the biocompatibility of calcium phosphate-magnesium phosphate-calcium silicate-bismuth cement (CMSBC).
    METHODS: Cytotoxicity test: Relative growth rate of L929 cells cultured in CMSBC extract was analyzed using cell counting kit-8 assay. Acute hemolysis test: The leaching solution of test samples, saline and distilled water were added into the rabbit anti-clotting, to detect the rate of hemolysis. Acute systemic toxicity test: CMSBC lead liquor and normal saline were respectively injected via the tail vein into the mice in experimental group and control group, respectively. The general situation of mice was observed at 24, 48, 72 hours respectively and body weight change was valued. Ames test: In the flat-plate incorporation test of Salmonella typhimurium, the average number of spontaneous revertants of TA97, TA98, TA100 and TA102 of CMSBC leaching liquor was calculated after incubation at 37 ℃ for 72 hours. S-9 mixture was added to the plates as an in vitro activation system.
    RESULTS AND CONCLUSION: The cytotoxicity of CMSBC in vitro was grade 0. Negative results from the acute hemolytic test, acute systemic toxicity test and Ames test of CMSBC indicate that this novel inorganic composite material has good biocompatibility and biosecurity.
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    Comparative assessment of two detergents for decellularized lung scaffolds 
    Ma Jin-hui, Yu Jie, Qiao Ye-ru, Hou Chen-wei, Ju Zhi-hai, Hei Fei-long
    2018, 22 (2):  248-253.  doi: 10.3969/j.issn.2095-4344.0014
    Abstract ( 379 )   PDF (1541KB) ( 154 )   Save
    BACKGROUND: It is quite difficult to produce a decellularized lung scaffold, in which cells are removed and the extracellular matrix components (ECM) are preserved effectively. Perfusion of detergent-enzymes is an effective method with wide applications for decellularized lung scaffolds.
    OBJECTIVE: To investigate the effects of two detergents (sodium deoxycholate, SDC and sodium dodecyl sulfate, SDS) on the preparation of decellularized lung scaffolds.
    METHODS: Twenty-four male Sprague-Dawley rats were randomized into three groups: control group with no intervention, SDC group and SDS group. Decellularized lung scaffolds were prepared by perfusion of SDC or SDS combined with enzymes. The rat lung tissues in the three groups were taken for histological staining, immunofluorescent staining and DNA quantification. A549 cells were cultured and seeded onto the decellularized lung scaffolds for 7 days followed by hematoxylin-eosin staining. The decellularized lung scaffolds prepared by perfusion of SDC or SDS were subcutaneously implanted into the rat back, and the implants were retrieved and assessed by Masson staining after 2 weeks.
    RESULTS AND CONCLUSION: In the control group, there were abundant cells in the lung tissues. In the other two groups, the decellularized lung scaffolds were nearly transparent, and the morphology of the SDC scaffold was more close to the native lung. There were no residual cells and nuclei on the two scaffolds, and the DNA content in the SDS and SDC groups was significantly lower than that in the control group (P < 0.01). At 7 days of culture, A549 cells cultured on the SDS and SDC scaffolds migrated from the edge to the center of the scaffold. Comparatively speaking, the migration ability of A549 cells on the SDC scaffolds was stronger, and there was obvious cell invasion and growth in the middle part of the lung. After 2 weeks of scaffold transplantation, the SDC implants poorly fused with the surrounding tissues, with a clear boundary, a large number of infiltrating cells distributed evenly, and intravascular blood cells were clearly visible; the number of new blood vessels with larger diameter in the SDC scaffold was significantly higher than that in the SDS scaffold. These findings indicate that the SDC scaffold has better biocompatibility than the SDS scaffold, which can fuse with the surrounding tissues faster and produce more infiltrating cells and new blood vessels.  
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    Combined use of adipose-derived stem cells and electrospun membrane for preparing sandwich-like cardiac cell sheets
    Wu Zhang-song, Zhu Hong-xia, Luo Zhi-qiang, Pan Wan-chun, Yang Fang, Lin Xin-yan, Zhu Yan-xia
    2018, 22 (2):  254-260.  doi: 10.3969/j.issn.2095-4344.0015
    Abstract ( 320 )   PDF (6618KB) ( 197 )   Save
    BACKGROUND: Increasing studies have shown that cell-sheet engineering is a more promising method for the treatment of myocardial infarction.
    OBJECTIVE: To construct sandwich-like myocardial cell sheets with electrospun chitosan-collagen membrane as support membrane and with adipose-derived stem cells as seed cells.
    METHODS: In this study, we prepared electrospun chitosan-collagen membranes at different mass ratio (7:3, 5:5) as a support membrane. Adipose-derived stem cells at passage 4 that were cultured in a thermo-sensitive petri dish for 3 days were seeded onto the two kinds of electrospun membranes at 20 ℃ for 15 minutes until the cell sheets rolled up. Then, the electrospun membranes and cell sheets with the cell layers facing up were placed together onto another thermo-sensitive petri dish in which adipose-derived stem cells were confluent completely. After 30 minutes of culture, the cell sheets were cultured in myocardial cell medium. Two weeks later, cell morphology was observed using multi-photon microscopy. Immunocytochemistry, western blot and flow cytometry were used to detect the expression of TnI and Cx43 in the myocardium. Real-time quantitative PCR was used to detect cardiomyocyte-specific gene expression.
    RESULTS AND CONCLUSION: From the results of scanning electronic microscopy (SEM) and propidium iodide (PI) staining, we could found that ADSCs grew easily on the chitosan-collagen (5:5) membrane, and there were more dead cells on the chitosan-collagen (7:3) membrane than on the chitosan-collagen (5:5) membrane. After 2 weeks of differentiation with the myocardial cell medium, higher troponin I and Cx43 protein expressions were observed on the chitosan-collagen (5:5) membrane (P < 0.05). Moreover, the mRNA levels of α-skA, β-MHC, TnI, Cx43, ANP, GATA-4 and Nkx2.5 were higher in the chitosan-collagen (5:5) membrane group than the chitosan-collagen (7:3) membrane group. All these results indicate that the chitosan-collagen (5:5) membrane is better for the growth and differentiation of adipose-derived stem cells, as well as for sandwich-like cell-sheet construction.
    中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程
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    Cell biocompatibility of an acellular heart scaffold of Sprague-Dawley neonatal rats
    Wei Ya-shu, Xu Yi-chen, Zhao Wen-jing, Wang Hui-feng, Liu Hong-jing, Xie Dan-ni, Chen Wei-ping
    2018, 22 (2):  261-266.  doi: 10.3969/j.issn.2095-4344.0016
    Abstract ( 322 )   PDF (5538KB) ( 195 )   Save
    BACKGROUND: Owing to the advantages of low sensitization and natural three-dimensional structure, good biocompatibility and cell affinity, acellular heart scaffold materials are of great current interest in cardiac tissue engineering.
    OBJECTIVE: To investigate the cytocompatibility of an acellular heart scaffold of neonatal rats.
    METHODS: In order to construct the seed cell-scaffold complex, passage 3 bone marrow mesenchymal stem cells (BMSCs) of Sprague-Dawley neonatal rats were cultured with an acellular heart scaffold of Sprague-Dawley neonatal rats for 7 and 14 days. Hematoxylin eosin staining and scanning electron microscopy were used to observe the growth of BMSCs in the scaffold. The cell-scaffold complex was induced in myocardial tissue lysate for 14 days. BMSCs with planar orientation differentiation for 14 and 20 days were used as control group. RT-PCR was used to detect the expression of myosin heavy chain α-MHC and zinc finger transcription factor GATA-4 in BMSCs.
    RESULTS AND CONCLUSION: (1) Hematoxylin-eosin staining showed the acellular heart scaffold contained a large number of eosinophilic fibrous structures, and the cell number of cell-scaffold complex after co-culture for 14 days was higher than that after co-culture for 7 days. Under the scanning electron microscope, a large amount of cells adhered to the fiber surface of the acellular scaffold at 14 days of co-culture. (2) BMSCs with planar orientation differentiation for 14 and 20 days had the bamboo-like and myotube-like structures. In the cell-scaffold complex with planar orientation differentiation for 14 days, the expression of α-MHC and GATA-4 could be detected, and their expression levels fulfilled the requirement for the presence of bamboo-like cells and myotube-like structure. These results indicate that the acellular heart scaffold exhibits good cytocompatibility.
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    Weak laser effects on the biocompatibility of chitosan and Nafion as implantable glucose sensor outer materials  
    Shen Hao, Liu Jun, Jing Wei-wei, Suo Yong-kuan, Chang Shi-jie, Sha Xian-zheng
    2018, 22 (2):  267-273.  doi: 10.3969/j.issn.2095-4344.0017
    Abstract ( 471 )   PDF (6640KB) ( 207 )   Save
    BACKGROUND: The biocompatibility of chitosan and Nafion can be improved by external factors.
    OBJECTIVE: To explore the effect of different weak laser irradiations (red, blue, green) on biocompatibility of porous chitosan membrane and the Nafion membrane.
    METHODS: (1) Porous chitosan membrane test: Forty-eight Sprague-Dawley rats were randomized into red, green, blue light groups (n=16 per group). Porous chitosan membranes (two membranes at each side) were implanted into the bilateral subcutaneous tissue of the rat back with the spine as the axis of symmetry, and then the four implanted membranes in each rat were irradiated by red light for 0, 2, 4, 6 minutes respectively. The irradiation lasted until sample collection at 7, 14, 28 and 56 days after implantation, and the samples were used for histological analysis. The same procedures were done in the blue and green light groups. (2) Nafion membrane test: Twenty-four Sprague-Dawley rats were randomized into red, blue and green light groups (n=8 per group). Nafion membranes (two membranes at each side) were implanted into the bilateral subcutaneous tissue of the rat back with the spine as the axis of symmetry, and then the four implanted membranes in each rat were irradiated by red light for 0, 2, 4, 6 minutes respectively. The irradiation lasted until sample collection at 7 and 14 days after implantation, and the samples were used for histological analysis. The same procedures were done in the blue and green light groups.
    RESULTS AND CONCLUSION: The content of red blood cells in blood vessels and vascular density around the membrane materials (porous chitosan membranes and Nafion membranes) increased after irradiated by red light (especially at 7 days after implantation); the red light had less influence on the inflammatory response and fibrous capsule thickness around the two kinds of membranes. The inflammatory cells percentage around the membrane materials irradiated by green light for 4 minutes was significantly reduced, and the blue light had less influence on inflammatory responses; blue and green lights showed effects on the fibrous capsule thickness and vascular density around the membrane materials, but the effect was not obvious. Thus, to a certain extent, weak lasers can improve the biocompatibility of PCSM and Nafion membrane.
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    Numerical simulation analysis of the internal flow field of a 3D biological printhead based on FLUENT
    Liu Dong-fang, Zhou Ji-ping, Shi Hong-can, Xu Xiao-dong, Jiang Ya-ni, Zhang Qi
    2018, 22 (2):  274-280.  doi: 10.3969/j.issn.2095-4344.0018
    Abstract ( 403 )   PDF (1254KB) ( 200 )   Save
    BACKGROUND: With the development of 3D printing technology, organ and tissue construction can be achieved by constructing a three-dimensional scaffold that is conducive to cell growth.
    OBJECTIVE: To solve the scaffold over-accumulation during 3D printing.
    METHODS: Fluent, a finite element analysis software developed by ANSYS Company in the United States, was used to analyze the extrusion process of print heads and to obtain suitable viscosity and extrusion pressure of materials for the 3D printing of cellulose gel composites. We then compared simulation results with experimental results.
    RESULTS AND CONCLUSION: The error between simulation results and experimental results was less than 5%. The simulated values at a kinetic viscosity of 45 and a pressure of 0.10-0.12 MPa solved the phenomenon of over-accumulation of cellulose gel composites during the 3D printing process, ensuring enough space for the 3D printed scaffold.
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    Graft healing and functional recovery after anterior cruciate ligament reconstruction: a case study of rehabilitation training
    Fu Tao, Wu Peng, Zhao Lin-liang, Cheng Ji
    2018, 22 (2):  281-287.  doi: 10.3969/j.issn.2095-4344.0019
    Abstract ( 525 )   PDF (1371KB) ( 160 )   Save
    BACKGROUND: Anterior cruciate ligament (ACL) injury directly impacts the individual's lower limb function. It is very important for althelets whether rehabilitation training after ACL reconstruction is reasonable, effective and can restore the normal function of the knee joint.
    OBJECTIVE: To explore the effect of rehabilitation training on graft healing and knee joint function recovery after ACL reconstruction.
    METHODS: An elite rugby player was enrolled and subjected to phased rehabilitation training after ACL reconstruction. MRI examination was done before and after rehabilitation training. Then, the following indicators were tested, including joint flexion of knee, leg circumference degrees, isokinetic muscle strength of the lower limb, feedback test, the test of YBT, the Balance Error Scoring System, feedforward test, static balance test on one foot, dynamic balance test on the feet, Lysholm knee score, anaerobic work of the upper extremity, torso strength, to analyze the graft healing, body shape, the knee joint function and physical quality improvement after ACL reconstruction.
    RESULTS AND CONCLUSION: After 10 months of phased rehabilitation training, the graft healed well; the knee flexion degree was back to normal; knee joint swelling basically eliminated; the muscle strength of the extensor flexor of the knee joint was back to over 95% of the normal level; the function of the injured knee joint was good and returned to a higher level; the Lysholm knee score was 85 points; the anaerobic work of the upper limbs and trunk strength reached to 120% of the normal level; and the quality of the body was greatly improved. To conclude, a great improvement in graft healing, knee joint function, recovery of muscle strength and physical qualities has been achieved in athletes who receive rehabilitation training after ACL reconstruction.
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    Real-time positioning of the ablation catheter ultrasonic probe in the heart: a simulation experiment  
    Li Xiang-fei, Duan Jun-tao, Su Zhi-jian
    2018, 22 (2):  288-293.  doi: 10.3969/j.issn.2095-4344.0020
    Abstract ( 371 )   PDF (1121KB) ( 172 )   Save
    BACKGROUND: Three-dimensional magnetic field positioning and three-dimensional electric field positioning are two main technologies used in heart ablation, but their required equipments are very expensive.
    OBJECTIVE: To develop a new method of ablation catheter positioning by combining ultrasonic probe with ablation catheter.
    METHODS: Three-dimensional data of human heart were obtained from the anatomical data set of the body, and then a three-dimensional vector model of the endocardial surface was established. The basic parameters and scanning strategy of ultrasonic probe were designed and calculated, to compile a corresponding simulation software. Based on the three-dimensional endocardial vector model, the detection data of the ultrasonic probe were obtained by simulation calculation and processed. Then, the target surface characteristics were reconstructed, matching with the surface features of the proposed vector model. The position of the probe was finally determined.
    RESULTS AND CONCLUSION: The three-dimensional model of the endocardium was established based on the anatomical data set, and the ultrasonic surface detection data were obtained by the simulated ultrasonic irradiation. The reconstructed surface model with high accuracy exhibited a desired match with the target area in the three-dimensional model of endocardium. The error of the probe position and its theoretical position fulfilled the requirement of positioning accuracy. In conclusion, the use of ultrasonic imaging technology can accurately position the catheter probe in the heart during heart ablation, providing an accurate and reliable navigation for the implementation of heart ablation.
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    Hyaluronic acid scaffolds: application research and product prospects
    Zhang Xiao-ou, Lv Yang, Mao Hua, Fan Xin-yi, Huang Si-ling, Guo Xue-ping
    2018, 22 (2):  294-302.  doi: 10.3969/j.issn.2095-4344.0021
    Abstract ( 503 )   PDF (1309KB) ( 264 )   Save
    BACKGROUND: Hyaluronic acid is an important component of extracellular matrix, has good biocompatibility, unique rheological properties and a variety of physiological functions. Therefore, it has wide application prospect in the tissue engineering.
    OBJECTIVE: To review the latest research progress in hyaluronic acid scaffold materials in different directions of tissue engineering.
    METHODS: Using the keywords of "hyaluronic acid, tissue engineering, regeneration, scaffold" in English and Chinese, we retrieved relevant articles published from January 2013 to September 2016 in the databases of PubMed, ScienceDirect and CNKI.
    RESULTS AND CONCLUSION: The application of hyaluronic acid tissue engineering scaffold materials mainly focuses on the regeneration of bone, cartilage, cardiovascular and nerve. The researchers optimize the composition, ratio of different materials, and modification or cross-linking methods to obtain the ideal scaffold materials to match the mechanical properties and physiological activity of the target tissue. However, there are not enough data on the influence of the molecular weight of hyaluronic acid and the original source of other raw materials on the scaffold properties. Further investigations are needed on the clinical transformation of hyaluronic acid tissue engineering products.
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    A patent analysis of biodegradable vascular scaffolds
    Zhang Xiao-dong, Sun Jing
    2018, 22 (2):  303-309.  doi: 10.3969/j.issn.2095-4344.0022
    Abstract ( 421 )   PDF (1600KB) ( 180 )   Save
    BACKGROUND: Biodegradable vascular stents show great commercial potential as the third generation of stents in the treatment of vascular stenosis, and there is naturally an intense competition in patents.
    OBJECTIVE: To analyze the patent information of biodegradable vascular scaffolds, which is helpful for better understanding of the development of biodegradable vascular scaffold technology, and provides reference for patent early warning.
    METHODS: Based on the Orbit patent database, through the manual screening, we conducted an analysis with FAMPAT patent family as analysis object from three aspects—the application trend, patent layout and competitor analysis. In combination with the development of technology and industrialization, important  Chinese patent list was also screened.
    RESULTS AND CONCLUSION: USA is in a leading position in this field, and China develops quickly. There are still a lot of research and patent layout space in the improvement of stent materials. Although some of basic patents have expired, patent infringement risks in China still needs to be investigated due to the intensive patent layout when Chinese enterprises develop their industrialization.
    中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程
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    Application of polymer interbody fusion cages
    Wang Peng, Sun Gui-sen, Li Hong-qi, Guo Long-sheng, Lang Ming-lei, Liu Wen-jun, Fan Wei-qiang
    2018, 22 (2):  310-315.  doi: 10.3969/j.issn.2095-4344.0023
    Abstract ( 337 )   PDF (1047KB) ( 169 )   Save
    BACKGROUND: Interbody fusion is an effective approach in the spinal surgery which is traditionally performed via auto/allogenic bone grafting, and it has a number of shortcomings as well as specific therapeutic effects. In the past few years, polymer interbody fusion cages have been gradually applied in clinical practice, which provides more options for spinal surgeons.
    OBJECTIVE: To introduce the advantages and disadvantages of degradable/non-degradable polymer materials respectively by analyzing their materialogy characteristics, and to further predict their application prospects.
    METHODS: PubMed, Ovid and CNKI were searched by computer to retrieve articles concerning the materialogy characteristics and application situation of common biomedical polymer materials in the spinal surgery. The key words were “spinal surgery, fusion cage, engineering plastic, degradable high polymer material” in Chinese and English, respectively.
    RESULTS AND CONCLUSION: Up to now, a variety of polymer materials, especially degradable polymer materials, are still at the stage of exploring and primary research, and their in-depth studies, including animal and biomechanics experiments, are still expected to be done gradually. Except for PEEK interbody fusion cages, some polymer materials are still lack of large sample and multi-center clinical trials before further application.
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    3D bioprinting: applications in cells, scaffolds and bone tissue engineering
    Hu Chao-ran, Qiu Bing
    2018, 22 (2):  316-322.  doi: 10.3969/j.issn.2095-4344.0024
    Abstract ( 548 )   PDF (1218KB) ( 252 )   Save
    BACKGROUND: 3D bioprinting is one of 3D printing technologies. Its characteristics are to plant biological materials or living cells in specific location to construct tissues and organs with complete biological functions. Until now, 3D bioprinting has been used to successfully produce various biological scaffolds, including bone tissue. In recent years, 3D bioprinting technology develops rapidly, which provides good prospects to regeneration and repair using tissue-engineered bone. 
    OBJECTIVE: To systemically introduce 3D bioprinting, to briefly clarify its fundamental principles, to summarize its current mainstream molding technologies and materials as well as their application in bone tissue engineering, and to discuss current bottleneck of 3D bioprinting in bone tissue engineering, providing reference for the development of regenerative medicine.
    METHODS: We searched CNKI, WanFang, PubMed databases for relevant articles published from 2005 to 2017. The keywords were “3D bioprinting, 3D bioprinted, bioink, bone tissue engineering, scaffold” in Chinese and English, respectively.
    RESULTS AND CONCLUSION: 3D bioprinting technology develops rapidly, which provides good prospect for future bone repair and transplantation. However, there are still several deficiencies, such as expensive printing equipment, laggard technology, strict requirements for bio-ink and medical team cooperation. Therefore, only depending on constant innovation in technological levels and material development, can 3D bioprinting make a further leap.
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    Properties of gelatin methacryloyl and its application in the skin tissue engineering
    Wu Xing, Liu Zhao-xing, Lin Huan-huan, Liu Sha, Sun Wei-jing, Chen Xiang-jun
    2018, 22 (2):  323-328.  doi: 10.3969/j.issn.2095-4344.0025
    Abstract ( 709 )   PDF (1335KB) ( 234 )   Save
    BACKGROUND: Gelatin methacryloyl has been widely used in the field of tissue engineering, as it has suitable biological properties, tunable physical and chemical properties, non-cytotoxic and non-immunogenicity.
    OBJECTIVE: To summarize the latest advances in the repair of skin and soft tissue damage using gelatin methacryl hydrogel materials. 
    METHODS: PubMed and SciFinder were retrieved for articles concerning gelatin methacrylate hydrogels published from January 2007 to August 2017. The key words were “seed cell, skin regeneration, wound vascularization, gelatin, gelatin methacryloyl, scaffold material, wound healing, microenvironment, tissue construction, skin tissue engineering”.
    RESULTS AND CONCLUSION: The gelatin methacryloyl hydrogel is very similar to the native extracellular matrix, and has a cell adhesion site, a matrix metalloproteinase-reactive peptide-based sequence and a cross-linkable property exhibiting good tissue affinity. The hydrogel has adjustable physical and chemical properties, a certain degree of adhesion and biodegradability, which make it an ideal cell scaffold, allowing all kinds of cells to proliferate and extend on its surface. Therefore, gelatin methacrylamide hydrogel has broad prospects in the skin tissue engineering, which can accelerate wound vascularization and epithelial tissue regeneration, improve wound healing rate, reduce the probability of infection, and improve the patient’s quality life. The gelatin methacrylamide hydrogen is proved to provide an efficient and portable gel dressing for burn wounds and war wounds, and it can also be used to fill skin and soft tissue defects such as trauma and ulcers, and cover cosmetic incisions.
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