1.The advance of bioceramics for bone tissue engineering scaffold material
Rui ZHONG ; Kai QIU ; Changxiu WAN
Chinese Medical Equipment Journal 1989;0(04):-
Bioceramics, because of their advantages such as biocompatibility and osteoconduction, have been widely used for bone repairing and bone substitute as bone tissue engineering materials. This study primarily compares the characteristics and the application range of some kinds of bioactive ceramics and biodegradable ceramics, and introduces their latest development in degradability and strength et al. Among these materials, calcium polyphosphate is a new material as bone tissue engineering scaffold. With a controllable degradation rate and the required strength, it has been paid much attention.
2.Galactosylated alginate-chitosan oligomer microcapsule:How to encapsulate hepatocytes?
Meng TIAN ; Bo HAN ; Chao YOU ; Changxiu WAN
Chinese Journal of Tissue Engineering Research 2013;(47):8215-8221
BACKGROUND:A novel galactosylated alginate-chitosan oligomer microcapsule has been prepared successful y. There is no report on hepatocytes encapsulated into the microcapsule prepared with chitosan oligomer and alginate sodium.
OBJECTIVE:To study the structure and properties of the previous novel galactosylated alginate-chitosan oligomer microcapsule, and then explore the morphology and function expression of the hepatocytes encapsulated.
METHODS:The membrane structure and thickness of the microcapsule (containing 50%or 30%galactosylated alginate) were observed using a laser confocal microscopy. Mechanical property was determined by mechanical rupture rate. Permeability was evaluated by release profile of fluoresceine isothiocyanate-labeled human serum albumin and immunoglobulin G. The morphology of hepatocytes in the microcapsule was observed using an inverted phase contrast microscopy. Function expression of the hepatocytes included albumin secretion and urea synthesis.
RESULTS AND CONCLUSION:The microcapsule had an asymmetry structure, with dense inner and loosened outer surfaces. With the increase of the galactosylated alginate, the membrane became loose, which indicated the negative charge on the alginate molecular chains was weakened after introduction of galactose, and thus electrostatic complex was affected. Mechanical property was correlated with both membrane structure and thickness. With the increase of the galactosylated alginate, the membrane structure became loose and the thickness was decreased, resulting in poor mechanical properties. The permeability was dependent mainly on the pore size of the skin layer of the membrane other than the loose sublayer. The prepared microcapsule can selectively pass through the human serum albumin and cut off immunoglobulin G, indicating skin pore size between human serum albumin and immunoglobulin G. The hepatocytes can form sphere assemble in the galactosylated alginate-chitosan oligomer microcapsule and exhibit improved albumin secretion and urea synthesis compared to the control in the alginate-chitosan oligomer microcapsule.
3.Galactosylated alginate and sodium alginate:What is the optimal mass ratio for maintaining the mechanical stability?
Meng TIAN ; Bo HAN ; Chao YOU ; Changxiu WAN
Chinese Journal of Tissue Engineering Research 2013;(25):4644-4651
10.3969/j.issn.2095-4344.2013.25.012
4.Construction of System Framework of Basic Dataset of Nursing Management Information for Hospital of TCM
Yu ZHAO ; Changxiu WAN ; Qiong ZHOU ; Qian XU
Journal of Medical Informatics 2017;38(5):39-42
Starting with the concepts of basic dataset and basic dataset of nursing management information of hospital of Tradtional Chinese Medicine (TCM),the paper introduces the research purpose,construction principle,construction method,construction contents and system framework of the basic dataset standard system of nursing management information of hospital of TCM,in order to lay a foundation for achieving nursing management data resource sharing and exchange of hospital of TCM.
5.The advance of bioactive peptide RGD in the research of bone regeneration.
Kai QIU ; Xin CHEN ; Tianquan LI ; Changxiu WAN
Journal of Biomedical Engineering 2003;20(3):546-549
Clinically, there has been so far no effective way to repair the bone-missing of large extent due to gash, infection and removal of tumor. The solution of this problem can be assisted by the addition of bioactive substances to substrate materials, because the growth of peripheral tissue and the fiber tissue growing the materials can be induced to the direction of bone-tissue by these biomaterials with bioactive peptides. The peptide Arg-Gly-Asp is the point between the integrin which comes from membrane and the ligand. In certain cases, the artificially synthesized RGD can be competitively combined with the integrin on cell surface, and outer-cell information is transmitted into cells, which will cause a series of physiological changes in cells. Presently, it is reported that the RGD has the ability to induce the growth of osteoblasts, restrain the adhesion between osteoclasts and substrates. This paper reviews and introduces the progress made with the work of RGD-inducing bone regeneration.
Biocompatible Materials
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Bone Regeneration
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drug effects
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physiology
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Cell Adhesion
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drug effects
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Oligopeptides
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administration & dosage
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chemistry
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pharmacology
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Osteoblasts
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drug effects
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physiology
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Osteoclasts
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drug effects
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physiology
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Tissue Engineering
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methods
6.Preparation and properties of porous co-substituted calcium polyphosphate scaffold as bone repair material*
Qifei JING ; Xu ZHANG ; Huixu XIE ; Qiguang WANG ; Xiaohua ZHANG ; Xixun YU ; Changxiu WAN
Chinese Journal of Tissue Engineering Research 2011;15(38):7045-7048
BACKGROUND: Ions doping is an important method for the modification of bioceramic.OBJECTIVE: To evaluate a novel co-substituted bioceramic scaffolds as bone repair material.METHODS: The microstructure and crystallization of the scaffolds were detected by scanning electron microscope and X-ray diffraction. Compression strength test,degradation test and cell culture experiment were assumed to evaluate the properties of KSCPP in vitro. After a short period of muscle pouches implantation,the performance of KSCPP in vivo was evaluated.RESULTS AND CONCLUSION: The results show that KSCPP scaffold has a higher compressive strength and degradation rate. Moreover,the MTT assay and implantation test reveal that the KSCPP scaffold exhibits lower cytotoxicity and better tissue biocompatibility than CPP and HA. The study proved the great potential of KSCPP in bone repair applications.
7.Effect of strontium-doped calcium polyphosphate on the secretion of vascular endothelial growth factor from osteoblastic cells
Fei LIU ; Yuanting XU ; Dawei REN ; Xixun YU ; Ting FENG ; Xiaohua ZHANG ; Changxiu WAN
Chinese Journal of Tissue Engineering Research 2009;13(47):9269-9272
BACKGROUND: Strontium-doped calcium polyphosphate (SCPP) is a new type of bone repair materials with good biocompatibility and controlled degradation. The preliminary studies of our group indicate their role in promoting angiogenesis,but its mechanism is unclear.OBJECTIVE: By co-culturing osteoblasts ROS17/2.8 with SCPP in vitro to observe cell proliferation and the secretion of vascular endothelial growth factor (VEGF).DESIGN, TIME AND SETTING: A contrast study was performed at the Laboratory of Tissue Engineering of Sichuan University from October 2008 to June 2009.MATERIALS: A series of calcium polyphosphate (CPP) respectively containing 0%, 1 %, 2%, 5%, 8%, and 10% Sr~(2+) were prepared. ROS17/2.8 osteoblastic cell strain was provided by Laboratory of Transplantation Immunity and Transplantation Engineering, West China Hospital, Sichuan University.METHODS: ①Preparation of cell scaffold complexes: The materials were placed in 24-well plates, then 300 μL cell suspension with a concentration of 2×10~7 cells/Lwas inoculated into each hole. These complexes were cultured for 14 days and the liquid was changed every two days. ②These complexes were measured by MTT assay to observe the proliferation of osteoblasts on the 1~(st), 3~(rd), 5~(th), 7~(th), 10~(th) and 14~(th) days, respectively. ③ The centrifugal supernatant of the complex cultured for seven days was measured by ELISA assay to check the secretion of VEGF.MAIN OUTCOME MEASURES: The proliferation of osteoblastic cells on SCPP and CPP was observed. The amount of VEGF protein secreting from osteoblastic cells was detected.RESULTS: The results of MTT showed that, compared with the CPP group, SCPP groups could promote the proliferation of osteoblasts, and 8% SCPP group was the best; ELISA results showed that, compared with the CPP group, SCPP groups could increase the amount of VEGF protein secretion, of which the promoting role of 8% SCPP was the most obvious (P < 0.05).CONCLUSION: When cultured with osteoblasts, SCPP can promote cell proliferation, and can significantly increase the secretion of VEGF; moreover, 8% SCPP is the best, which reveals a certain mechanism of its promoting angiogenesis.
8.Effect of strontium-doped calcium polyphosphate on endothelial cells-derived angiogenic factor matrix metalloproteinase-2 expression
Dawei REN ; Fei LIU ; Xixun YU ; Xiaowei DENG ; Xiaohua ZHANG ; Changxiu WAN
Chinese Journal of Tissue Engineering Research 2009;13(38):7433-7436
BACKGROUND: Strontium-doped calcium polyphosphate (SCPP), as a new repairing material, has been demonstrated to have favorable biocompatibility and biodegradability and some effects on promoting self-angiogenesis. However, the mechanism remains still unknown. OBJECTIVE: Endothelial cells were cultured with SCPP scaffolds in vitro, as well as the cell proliferation and angiogenic factor matrix metalloproteinase-2 (MMP-2) secretion were observed. DESIGN,TIME AND SETTING: A contrast study was performed at the Laboratory of Tissue Engineering of Sichuan University from September 2008 to April 2009. MATERIALS: A series of calcium polyphosphate (CPP) respectively containing 1 %, 2%, 5%, 8%, and 10% Sr~(2+) were prepared.METHODS: ① Materials were plated on 24-well culture plate,and endothelial cell suspension (300 μL) were seeded on 24-well culture plate at the concentration of 3×10~7/L and cultured with 200 uL RPMI1640 culture media. Endothelial cell proliferation was observed using MTT method at days 1,3,5, and 7 after culture. ② CPP and 8% SCPP were plated on 24-well culture plate, and endothelial cell suspension (300 uL) was then incubated in 24-well culture plate at the concentration of 1x10~8/L and cultured with 600 uL RPMI1640 culture media. The morphology of endothelial cells was observed by scanning electron microscopy (SEM) at day 5 after culture.③ Endothelial cells were co-cultured with SCPP of various Sr~(2+) contents for 5 days. After confluence, cells were centrifuged to obtain supernatant. Angiogenic factor MMP-2 secretion was evaluated by ELISA assay.MAIN OUTCOME MEASURES: The proliferation and morphology of endothelial cells on SCPP and CPP were observed. The amount of endothelial cells-derived MMP-2 protein secretion was detected. RESULTS: MTT method demonstrated that the proliferation of endothelial cells on the 8% SCPP scaffold showed a higher level compared to CPP, and other SCPP groups. Scanning electron microscope results suggested that endothelial cells on 8% SCPP had a better growth status and biological activity. ELISA results indicated that angiogenic factor MMP-2 expression on the SCPP was promoted compared with that of CPP, and 8% SCPP showed the highest expression (P < 0.05). CONCLUSION: SCPP has good compatibility with endothelial cells,promoting angiogenesis and enhancing the angiogenic factor MMP-2 expression.
9.Research in synthesis of bioactive peptide RGD and the method for its grafting on PET surface.
Qiang ZHAO ; Changxiu WAN ; Jianwei LIU ; Kai QIU
Journal of Biomedical Engineering 2003;20(3):384-387
The aim of this experiment is to graft synthesizing Arg-Gly-Asp peptides (RGD) on the surface of polymer materials, combine endothelial cells with its special site, enhance the adhesion of endothelial cells on the surface, promote the blood compatibility of the biomaterials. Carboxy group (-COOH) was grafted on the materials surface by ultraviolet (UV) radiation, and the RGD serial obtained by liquid phase synthesis was successfully grafted on the disposed materials by chemical reaction. The endothelialization experiment was made also. The grafting results were measured by X-ray photoelectron spectroscopy (XPS), and endothelialization was observed using optical microscope and scanning electron microscope (SEM). The results indicated that the method improves the effect of materials endothelialization. The experiment has made successful use of UV grafting and chemical coupling methods to graft bioactive RGD onto PET film surface. This is a new method of grafting bioactive peptide.
Biocompatible Materials
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chemistry
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Cells, Cultured
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Cells, Immobilized
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Endothelium
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cytology
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drug effects
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Humans
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Oligopeptides
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chemical synthesis
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chemistry
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pharmacology
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Polyethylene Terephthalates
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chemistry
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Surface Properties
10.Advances in research on calcium polyphosphate bioceramic for bone tissue engineering scaffold.
Kai QIU ; Xin CHEN ; Changxiu WAN
Journal of Biomedical Engineering 2005;22(3):614-617
Bone tissue engineering is a novel, developing and challenging science which provides a new way to repair bone lost from injury and disease. Porous calcium polyphosphate bioceramic is one kind of absorptable bioceramic. Owing to its fine biocompatibility and degradability, more and more pieces of research wark have been carried out in bone tissue engineering, and because of its special characteristics, calcium polyphosphate bioceramic is regarded as a promising material for solving the problem of how to match the degradation velocity of scaffold with the velocity of cell growth. The recent research of using calcium polyphosphate bioceramic as the scaffold in bone tissue engineering is summarized, including the property, synthesis and advances.
Bone Substitutes
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chemistry
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Bone and Bones
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Calcium Phosphates
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chemistry
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Humans
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Porosity
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Tissue Engineering
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Tissue Scaffolds
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chemistry