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19 November 2010, Volume 14 Issue 47 Previous Issue    Next Issue

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Feasibility of small intestinal submucosa acellular matrix as vaginal smooth muscle cell carrier Li Qing-lin, Liu Wei, Li Wen-fang, Liu De-wu, Zhang Jie 2010, 14 (47):  8741-8746.  doi: 10.3969/j.issn.1673-8225.2010.47.001 Abstract ( 289 )   PDF (819KB) ( 457 )   Save BACKGROUND: The main scaffold for vaginal tissue engineering study, polyglycolic acid, has rapid degradation and other defects. Acellular natural scaffold material, in particular small intestinal submucosa, is becoming a hot spot of tissue engineering research. OBJECTIVE: To explore the possibility of using porcine small intestinal submucosa acellular matrix as a cell carrier in vaginal tissue engineering. METHODS: The vaginal smooth muscle tissues were separated from New Zealand female rabbits, and cultured by tissue explant + collagen digestion methods in vitro, then passaged and incubated into self-made porcine small intestinal submucosa matrix as a seed cell. Morphology, growth and proliferation of the cells were monitored under the inverted microscope. The cell-matrix complex was harvested at 1, 2, 3, 4 weeks for histological examination. RESULTS AND CONCLUSION: ①The vaginal smooth muscle cells were successfully cultured in vitro. The cells were fusiform and aggregated in Petri dish, forming “peak-valley” structure. ② The submucosa acellular matrix was white, semitransparent and tough. No cell component could be seen by hematoxylin-eosin staining. ③ Specimens of vaginal smooth muscle cell-intestinal submucosa were stained by hematoxylin-eosin, cell components were increasing gradually and grew from surface to deep site under light microscope. ④ Specimens of vaginal smooth muscle cell-intestinal submucosa were stained by monoclonal antibody of anti-rabbit smooth muscle a-actin by immunohistochemistry. The a-actin positive cells can be seen. Results preliminarily prove that porcine intestinal submucosa matrix can be used as smooth muscle cells carrier. Related Articles | Metrics

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Effects of fibrin glue on the proliferation and viability of adipose tissue-derived stem cells Zhang Xue-lian, Ma Yi-tong, Wang Chang-yong, Ma Xiang, Adila•Azhati, Liu Fen, Chen Bang-dang 2010, 14 (47):  8747-8750.  doi: 10.3969/j.issn.1673-8225.2010.47.002 Abstract ( 352 )   PDF (437KB) ( 367 )   Save BACKGROUND: Many biological scaffolds are used in carrying seed cells, however, there is no criterion about the co-culture of fibrin glue with adipose tissue-derived stem cells and the evaluation of the proliferation and viability of seed cells on the scaffolds. OBJECTIVE: To investigate the effects of fibrin glue on the proliferation and viability of rat adipose tissue-derived stem cells cultured in vitro, and to provide the experimental evidence for injectable tissue engineered myocardial treatment for myocardial infarction. METHODS: Adipose tissue-derived stem cells were isolated from rats and then cultured. Their immunophenotype was identified by flow cytometry. Adipose tissue-derived stem cells were co-cultured with fibrin glue. The proliferation of adipose tissue-derived stem cells were tested by MTT assay and cell viability was assessed with LIVE/DEAD fluorescence double stain. RESULTS AND CONCLUSION: The adipose tissue-derived stem cells of rats were positive for CD90 and CD105, but negative for CD34 and CD45. MTT assay showed that adipose tissue-derived stem cells proliferated faster in fibrin glue group than the control group (P < 0.05); LIVE/DEAD fluorescence double stain showed that adipose tissue-derived stem cells grew well in fibrin glue. The viability of adipose tissue-derived stem cells maintained > 90% and the mortality was < 7% at 24 hours and 72 hours. Adipose tissue-derived stem cells well proliferate and survive in fibrin glue, fibrin scaffold may work as a carrier in deliverying adipose tissue-derived stem cells for injectable myocardial tissue engineering study. Related Articles | Metrics

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Survival and differentiation of neural stem cells adhered to muscle basal lamina tissue engineering scaffolds Song Yu,Liu Jia-mei, Xue Hui, Zhang Xiu-ying, Tian Xiao-wei 2010, 14 (47):  8751-8754.  doi: 10.3969/j.issn.1673-8225.2010.47.003 Abstract ( 402 )   PDF (335KB) ( 445 )   Save BACKGROUND: Many researches have shown that neural stem cell can promote the rat neural function recover of spinal injury. Muscle basal lamina has a good biocompatibility and degradability. Therefore the combination of muscle and neural stem cells to be a new nerve tissue engineering scaffold has been considered.  OBJECTIVE: To observe the survival and differentiation of neural stem cells as seed cells adhered to the muscle basal lamina as a scaffold. METHODS: Rat neural stem cells were isolated, cultured and then identified in vitro. Following preparation of acellular bone muscle basal lamina scaffolds by chemical extraction method, the neural stem cells were implanted into the scaffolds. After seven days of cultivation, the survival and differentiation of neural stem cells were detected by immunohistochemical technique, and the ultra-structure was observed under a scanning electron microscope. RESULTS AND CONCLUTION: On the fifth day of cultivation, a great amount of neurospheres were seen by Nestin immunofluorescence. Following 7-day culture and differentiation in serum medium, the neural stem cells were used for anti-NF and anti-GFAP immunofluorescent staining. NF and GFAP positive cells were found under the microscope, which indicated that the cultured neural stem cells owned multi-lineage differentiation potential. Hemotoxylin and eosin (HE) staining showed that myocytes disappeared from the muscle basal lamina and there were roughly parallel tunnels inside the muscle basal lamina scaffolds. Immunofluorescent staining showed that the neural stem cells adhered to the scaffolds still had the characteristics of stem cells and could differentiate into neurons and neurogliocytes. The neural stem cells were firmly attached to the muscle basal lamina under the scanning electron microscope. These findings indicated that nerve tissue engineering scaffold has a good biocompatibility and can be used for in vivo transplantation to treat nervous system diseases, such as spinal cord injury. Related Articles | Metrics

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Effect of polylysine and gelatin on proliferation and differentiation of neural stem cells Sun Li1, Zhang Li, Hu Xiao-feng, Zhang Hui, Luo Qiang, Wang Xin-sheng, Zhu Deng-xiang, Bo Ai-hua 2010, 14 (47):  8755-8758.  doi: 10.3969/j.issn.1673-8225.2010.47.004 Abstract ( 432 )   PDF (318KB) ( 429 )   Save BACKGROUND: Currently, there are plenty of the investigations regarding the induced differentiation of neural stem cells (NSCs) in vitro, but the process of differentiation is difficult to control, many methods are complicated to operate, and the proportions of differentiation are very low. OBJECTIVE: To discuss in vitro cultivation of rat embryonic forebrain NSCs and to observe the differentiation rule of NSCs. METHODS: The forebrains were isolated from fetal rats under aseptic conditions, to prepare monocell suspension, and cultured with DMEM/F12 medium containing N2 at the density of 1×1011/L. In the process of cultivating, BrdU was added to mark NSC spheres. The induced differentiation experiment was divided into three groups: polylysine culture plate, gelatin plate and no plate culture groups. 20% volume fraction of embryonic bovine serum was used to stimulate the differentiation. Immunohistochemistry method was applied to detect the level of nestin and BrdU, as well as NSCs differentiation into nerve cells in the serum induction. RESULTS AND CONCLUSION: The cells presented the NSC-like growth and continuous proliferative capacity, they can subculture. Nestin and BrdU were both positive in passaged neurospheres. The inducing differentiation effect of the polylysine culture plate group and the gelatin plate group was greater than no plate culture group (P < 0.01), and the polylysine culture plate group had a little higher percentage of neurons differentiating than the gelatin plate group (P > 0.05). The result of immunohistochemistry was glial fibrillary acidic protein-positive and microtubule-associated protein-2-positive. Rat embryonic forebrain is full of NSCs. The polylysine and the gelatin as cells holder in inducing NSCs differentiation can improve NSCs differentiation and mostly differentiate into the astrocytes through differentiation observation. Related Articles | Metrics

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Calcium hydrogen phosphate/collagen composite versus hydroxyapatite/collagen composite for repair of massive bone defects Hu Qing-liu 2010, 14 (47):  8759-8763.  doi: 10.3969/j.issn.1673-8225.2010.47.005 Abstract ( 287 )   PDF (455KB) ( 468 )   Save BACKGROUND: Hydroxyapatite or the complex with other components has become the international standard materials for bone repair, which has been widely used in clinical and experimental research. Their biocompatibility has been fully verified, but poor performance of degradability and limited ability to induce bone regeneration are also recognized. We believe that hydroxyapatite as a bone induction material is only to mechanically mimic the composition of natural bone, other calcium phosphate salts as inorganic components of bone composites may lead to breakthrough the fixed current scientific thinking and provide a new aspect of artificial bone development. OBJECTIVE: To compare the osteo-conductivity and osteo-inductivity of calcium hydrogen phosphate/collagen (DCP/CO) composite with hydroxyapatite/collagen (HA/CO) composite. METHODS: Fifteen New Zealand rabbits were used in this experiment to prepare a 10-mm bone defect at left ulnas, and then implanted with DCP/CO composite, standard HA/CO composite and synthesized HA/CO composites. The rabbits were killed at 92 postoperative days after the completion of X-ray photography, and processed into anatomical observation and histological examination. RESULTS AND CONCLUSION: X-ray photography showed that, the defects were completely healed owing to bone hyperblastosis in the DCP/CO composite group at 92 days after surgery, anatomical observation demonstrated that the repaired defects were similar to the appearance of non-surgical site. Histological sections showed the bone lamella formed at the defect site and fully ossified, with obvious osteon, there was no remarkable layered bone lamella, osteocytes were visible in the scattered absconsiones, and new vessels in central canal, without artificial bone residue. The artificial bone was completely biodegraded and absorbed. At 92 days after surgery, the defects of ulnas in standard HA/CO group were broken easily, indicating poor ossification; in HA/CO group the defect remained unrpaired. DCP/CO composite (imitating cancellous bone bioactive bone), produced by Nanjing Medicine Science & Technology Co., Ltd., has a superior osteo-conductivity and osteo-inductivity than HA/CO composite. Related Articles | Metrics

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Histological variation of heterogeneous biological bone screw applied in fracture model Zhang Ying, Liu De-hua, Xia Yuan-jun, Wu Wen, Xie Hui-bin, Tan Xin-yu, Liu Han-hui 2010, 14 (47):  8764-8768.  doi: 10.3969/j.issn.1673-8225.2010.47.006 Abstract ( 309 )   PDF (345KB) ( 381 )   Save BACKGROUND: In recent years, the fixation of articular fracture using absorbable screws is achieved in more and more cases, but mechanical properties are instable and early absorption results in fixation failure. Therefore, it is necessary to develop xenogeneic bone screws of stable performance and affordable cost to be an alternative of absorbable screw. OBJECTIVE: To observe the histology variation of heterogeneous biological bone screws applying in rabbit fracture model. METHODS: Healthy adult New Zealand rabbits were adopted to prepare left femur condylar fracture in animal models and then were divided into experiment group and control group, which were respectively fixed using heterogeneous biological bone screws and absorbable polylactic screws. At 2, 4, 6, 8, 12, 24 weeks postoperation, the screws and tissue around bone screw were observed on histology. RESULTS AND CONCLUSION: Animals in both groups gradually restored the activities 1-2 days later, and the activities were normal at 10 days, local wound had no swelling, ulceration, exudation or necrosis, all wounds completely healed in 2 weeks. Pathological sections revealed that at 2-4 weeks, inflammatory cell infiltrated between biological bone screw and host bone; at 6-12 weeks, the number of inflammatory cells gradually reduced, fibrosis was significantly obvious than before, fibrous edges appeared some osteoclasts; at 24 weeks, fiber layer thickness reduced, the number of osteoclasts significantly increased, and bone bridge was visible with host bone. Inflammatory cells infiltrated on the surface of the absorbable screw channel at 2-4 weeks after surgery; at 6-8 weeks, cancellous bone inflammatory cell infiltration decreased, fibrosis was significant, and no infiltration of osteoclasts was observed; at 12-24 weeks, the thickness of fibrous connective tissue layer on surface of the screw channel became thicker, some osteoclasts infiltrated in the host cancellous bone. Biological bone screws could induce ossification to a certain extent, and no obvious immunological rejection is observed in this experiment. Related Articles | Metrics

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Preparation and biological detection of demineralized cancellous bone scaffolds Yang Yuan, Lin Chun-bo, Chen Wei-ping 2010, 14 (47):  8769-8772.  doi: 10.3969/j.issn.1673-8225.2010.47.007 Abstract ( 311 )   PDF (308KB) ( 318 )   Save BACKGROUND: Collagen is the main component of demineralized cancellous bone, because of its excellent three-dimensional space and growth factors that promote cellular proliferation and differentiation, it has a dual function of bone conduction and bone induction, but there are no amendments of a standard scientific preparation process. OBJECTIVE: To prepare rabbit demineralized cancellous bone, to detect the porosity, degradation rate and biocompatibility, and to investigate the feasibility of demineralized cancellous bone used for tissue engineering scaffolds. METHODS: Based on Urist’s method, demineralized cancellous bone was prepared using a new method, and the porosity, in vitro degradation rate, cell viability and ossification ability of inducing bone marrow mesenchymal stem cells were determined. The experiment was divided into three groups at decalcification 3, 24, 48 hours. The other processing steps were the same. RESULTS AND CONCLUSION: The porosity of decalcification 3, 24, 48 hours was 76.56%, 81.25%, 84.38%; complete degradation time was 64, 59, 53 days, respectively. Cells in 1-3 days after incubation were latent phase, entered the logarithmic growth phase at 5 days, then entered the stagnate phase. The induced bone marrow mesenchymal stem cells were stained positive for alkaline phosphatase. The demineralized cancellous bone prepared by new methods has no toxicity and can meet the biological characteristics requirements of bone tissue engineering scaffold materials. Related Articles | Metrics

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Vertebral body defect augmentation with silk fibroin/calcium phosphate cement in vitro Chen Xiao-qing, Zhao Jian, Zhang Feng, Wang Gen-lin, Gan Min-feng, Gu Yong, Zhu Xue-song, Yang Hui-lin 2010, 14 (47):  8773-8776.  doi: 10.3969/j.issn.1673-8225.2010.47.008 Abstract ( 239 )   PDF (252KB) ( 363 )   Save BACKGROUND: Injection into the vertebral fracture model of corpse is the most common used method for screening bone cement biomechanically in vertebral augmentation. This model can hardly be applied in the further studies in vivo. OBJECTIVE: To develop a vertebral body defect model for screening vertebral augmentation filler materials and to evaluate the mechanical property after the bone cement augmentation. METHODS: Forty-eight lumbar vertebrae harvested from ten fresh skeletally mature female sheep cadavers were evenly assigned to eight groups, 6 vertebrae in each. Four groups of vertebrae were drilled in the perpendicular direction to center of the vertebra, with the different drills at a diameter of 2.0, 4.0, 6.0, 8.0, to form a cylindrical bone defect. All vertebrae were compressed to determine the strength and stiffness, which were compared with normal vertebrae group. Based on the biomechanical test, a certain defect was selected as the vertebral body defect model. The remaining 3 groups were prepared into bone defect models, and then augmented by calcium phosphate cement, silk fibroin/calcium phosphate cement, polymethyl methacrylate, respectively. The biomechanical test was performed after setting for 24 hours in simulated body fluid. RESULTS AND CONCLUSION: The compressive strength and stiffness of the vertebrae with bone defect gradually decreased as the diameter of the bone defect increased, and the decline was remarkable in the vertebrae at a diameter of 6.0 mm. After bone defect in vertebrae was produced using a 6.0-mm-diameter drill, there was no difference in the compressive strength and stiffness of the vertebrae among silk fibroin/calcium phosphate cement, polymethyl methacrylate compared with normal vertebrae group (P > 0.05), while calcium phosphate cement group had a lower value compared with normal vertebrae group (P < 0.05). The sheep vertebra with a 6.0-mm diameter and 10.0-mm depth defect is a suitable model to screen vertebral augmentation filler materials. This model keeps the vertebral figuration intact and can be used to adjust the performance of vertebral enhancer in vitro, so it can be used in further studies in vivo. Silk fibroin/calcium phosphate cement has a prompt and efficient augmentation effect in bone defect vertebral model. Related Articles | Metrics

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Tissue engineered blood vessels constructed by implanting different densities of cells on decellularized vascular matrix Chi Yi-fan, Xu Hui, Lin Ming-shan, Hou Wen-ming, Niu Zhao-zhuo, Sun Yong, Sun Zhong-dong, Sun Long, Sheng Wei 2010, 14 (47):  8779-8782.  doi: 10.3969/j.issn.1673-8225.2010.47.010 Abstract ( 276 )   PDF (318KB) ( 383 )   Save BACKGROUND: Previous studies have shown that decellularized vascular matrix prepared is suitable for the growth of smooth muscle cells and endothelial progenitor cells, but the effect of cell inoculation density on cell coverage of vascular matrix in co-culture model remains unclear. OBJECTIVE: To observe the growth of seeding cells at different densities implanted on decellularized vascular matrix. METHODS: Cell implantation was performed using two-step seeding method. Firstly, smooth muscle cells were seeded onto the decellularized vascular matrix with different densities, and cultured for 3 days, and then endothelial progenitor cells were then seeded onto the smooth muscle cells-vascular matrix compound with different densities, to construct lamellar tissue engineered materials. The samples were harvested at 3 days and 1 week after the implantation of endothelial progenitor cells, cell growth was observed by scanning electron microscope. RESULTS AND CONCLUSION: Smooth muscle cells and endothelial progenitor cells grew well on the decellularized vascular matrix, cells arranged differently on the matrix with different seeding densities; with the increase of seeding density, cells showed higher covering rate on the material surface. Tissue engineering blood vessels can be constructed by implanting suitable density of seeding cells to the decellularized vascular matrix using a two-step method. Related Articles | Metrics

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Preparation of extracellular matrix of human umbilical veins Wang Hai-jiang, Fan Ying-zhong, Li Lu-ping, Zhang Zhen, Zhang Da 2010, 14 (47):  8783-8786.  doi: 10.3969/j.issn.1673-8225.2010.47.011 Abstract ( 318 )   PDF (308KB) ( 383 )   Save BACKGROUND: Preparation of extracellular matrix (ECM) aims to remove the cellular components in tissues, there is no uniform standard for the current acellular methods, but the prepared ECM should be proved to be without residual cells.  OBJECTIVE: To prepare human umbilical vein ECM by using hypotonic and hypertonic solutions, detergent and proteinase in a multistep process, mixed solution of Triton X-100 and ammonia water, and to explore the ideal method of preparing human umbilical vein ECM.  METHODS: ECM of human umbilical veins was prepared by use of hypotonic and hypertonic solutions, detergent and proteinase in a multistep process and solution of Triton X-100 and NH3·H2O. The physical properties and hematoxylin-eosin staining of human umbilical vein before and after acellular matrix were observed, the amount of residual cell debris in 50 images at 400 magnification was measured. RESULTS AND CONCLUSION: The acellular umbilical veins exhibited translucent porcelain-white jelly-like tubular structure. The cell components of the human umbilical veins resulting from hypotonic and hypertonic solutions, detergent and proteinase were almost removed, ECM maintained an integrity, and fibrous structures were preserved. ECM resulting from solution of Triton-X100 and NH3·H2O had different quantities of remaining cellular elements. There were significant differences between the two groups (P < 0.05). Hypotonic and hypertonic solutions, detergent and proteinase are ideal methods to prepare ECM from human umbilical veins. Related Articles | Metrics

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System evaluation of different materials and types of periodontal splints in periodontal repair Wang Xing, He Hui-yu, Man Yun-na, Wu Yan-ni, Wu Tai-xiang 2010, 14 (47):  8787-8790.  doi: 10.3969/j.issn.1673-8225.2010.47.012 Abstract ( 356 )   PDF (235KB) ( 475 )   Save BACKGROUND: Loosen teeth are a long-term problem for dentists in treatment of periodontal disease, the use of periodontal splints is still in dispute.　 OBJECTIVE: To assess the effectiveness and safety of periodontal splints for the treatment of periodontal mobile teeth. METHODS: A computer research of Cochrane Library (Issue 4, 2009), MEDLINE (1966/November 2009), EMbase (1980/November 2009), China Biomedicine Database (1978/2009), CNKI (1989/2009), and VIP (1989/2009) was performed to search randomized controlled trials for periodontal splints in treatment of periodontal repair. Quality assessment and data extraction were performed by two reviewers independently. Statistical analysis of the study data was performed with RevMan 5.0 software offered by Cochrane Cooperative net. RESULTS AND CONCLUSION: Nine studies of randomized controlled trials were included. The included studies did not report the splint-related serious adverse reactions. Existing researches show that periodontal splint can improve the mobility of loosed teeth with periodontal diseases and periodontal status, permanent splints are more effective than temporary splints, fixed permanent splints are more effective than removable permanent splints, super-strong fiber splints are more effective than traditional stainless steel wire combined resin splints, precious metal splints are more effective than cheap metal splints. Due to few high-quality randomized controlled trials and limited cases of patients, there is a high possibility of selection bias and publication bias. Related Articles | Metrics

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Biodegradability and biocompatibility of ε-caprolactone and L-lactide copolym Gao Xi-xiang, Zhang Jian, Chen Bing, Yu Heng-xi, Li Jian-xin, Zhang Shu-wen, Meng Yan, Han Jian, Ye Lin, Feng Zeng-guo 2010, 14 (47):  8791-8794.  doi: 10.3969/j.issn.1673-8225.2010.47.013 Abstract ( 274 )   PDF (485KB) ( 404 )   Save BACKGROUND: Copolymers of ε-caprolactone and L-lactide have good mechanical property, and regulable degradation rate. They become popular as a tissue engineered vascular graft. OBJECTIVE: To study the biodegradability and biocompatibility of ε-caprolactone and L-lactide copolymers. METHODS: A kind of ε-caprolactone/L-lactide copolymer with different compositions and molecular weights was prepared by varying the monomer molar ratios in feed. The biodegradability was studied in lipase solution (accelerated degradation). The biocompatibility was also studied by implantation in vivo. RESULTS AND CONCLUSION: The ε-caprolactone/L-lactide copolymer at 75/25 molar ratio has a great mechanical property through the biodegradation, as well as high biocompatibility in vivo. It is suitable for the preparation of artificial blood vessel of tissue engineering. Related Articles | Metrics

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Proliferation and differentiation of bone marrow mesenchymal stem cells cultured on hydroxyapatite/collagen composite scaffolds Song Qin, Yan Jun, Guo Xiao-qiang, Yao Qian, Yu Xiao-bing○ 2010, 14 (47):  8795-8799.  doi: 10.3969/j.issn.1673-8225.2010.47.014 Abstract ( 485 )   PDF (370KB) ( 458 )   Save BACKGROUND: Presently collagen as cell three-dimensional scaffold in vitro, has been mainly used in tissue engineering. But collagen scaffolds has low mechanical strength, and weak fatigue resistance. Therefore hydroxyapatite/collagen composite scaffolds are prepared to explore the biocompatibility and bioactivity of the composite scaffold. OBJECTIVE: To investigate the proliferation and differentiation of bone marrow mesenchymal stem cells (MSCs) cultured on hydroxyapatite/collagen composite scaffolds. METHODS: MSCs were isolated from SD rats using adherence method and inoculated into the dish, collagen scaffold and hydroxyapatite/collagen composite scaffold respectively. The cellular growth under three conditions was observed, the cellular proliferation was assessed using MTT assay. The differentiation of MSCs was characterized by alkaline phosphatase activity and the secretion of collagen at 14 and 21 days after the culture. RESULTS AND CONCLUSION: The MSCs well spread on the hydroxyapatite/collagen composite scaffolds, and showed a higher proliferation rate than that cultured on the collagen scaffold and dish. The quantitative examination of alkaline phosphatase activity and secretion of collagen indicated that the cells cultured on the hydroxyapatite/collagen composite scaffolds expressed a higher level than that on the collagen scaffold and dish. The hydroxyapatite/collagen composite scaffold can promote the differentiation and proliferation of MSCs, and induce MSCs differentiate into osteoblasts. Related Articles | Metrics

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Preparation of integrin αvβ3 targeted liposome and its targeted ability in vitro Xie Xu-pin, Zhou Zhao-xiong, Hu Ya-li, Zhang Bai-gen, Zhang Ji-wei 2010, 14 (47):  8800-8804.  doi: 10.3969/j.issn.1673-8225.2010.47.015 Abstract ( 383 )   PDF (742KB) ( 459 )   Save BACKGROUND: RGD-containing peptides are recognition sites of a variety of integrin and are widely used in the design of targeting nanoparticles for drug delivery system due to its small molecular weight, stability, easy preparation, and no immunogenicity. OBJECTIVE: To synthesize the integrin αvβ3 targeted liposome, loading drugs and with RGD oligopeptide as main binding components, and to assess its receptor targeted ability through in vitro cytology experiment. METHODS: The synthetic RGD oligopeptide served as targeted molecular probe, the liposomes conjugated with Arg-Gly-Asp (RGD) peptides were made by high pressure homogeneous processing methods. The morphology and size were examined by scanning electron microscope and laser particle size analyzer. The specific mark of vascular smooth muscle cells was analyzed with flow cytometry, as well as the ex vivo release and in vitro targeting ability of loaded drugs. RESULTS AND CONCLUSION: The particle size of targeted liposome was (175±6) nm, and the encapsulation efficiency was (96.33±1.02)%.The targeted liposome loading drugs could release persisted over 5 days in vitro. The targeted liposome had specific affinity for αvβ3 integrin and could enter cells with receptor-mediated endocytosis. The integrin αvβ3 targeted liposomes have relatively high encapsulation efficiency and sustained release pattern, it can bind particularly with αvβ3 integrin and may become a new type receptor-mediated targeting agent. Related Articles | Metrics

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Effect of dispersant on polystyrene preparation using suspension polymerization and morphology analysis Liang Bo, Han Feng-lan, Yang Peng-yuan 2010, 14 (47):  8805-8808.  doi: 10.3969/j.issn.1673-8225.2010.47.016 Abstract ( 403 )   PDF (1172KB) ( 609 )   Save BACKGROUND: Polystyrene microspheres have been widely used in solid-phase organic synthesis, biomedical applications, polymeric absorption and supported catalyst based on high specific surface area, strong absorbability, good mechanical property, strong reactivity, great surface activity and recycling. Therefore it is a lasting and important task for daily process control to produce polystyrene microspheres at appropriate particle size according to market demand. OBJECTIVE: To investigate the influence of dispersant amount, type and adding times on the dispersed properties of polystyrene microspheres. METHODS: The polystyrene microspheres were prepared by suspension polymerization in water as dispersing medium, without adding any stabilizers. Polystyrene 0.5 g was weighed at all the experimental conditions to measure the number of the particles contained. As for the same quality of polystyrene particles, more particles contained indicated smaller particle size. The surface morphology and particle size distribution of polystyrene particles were observed under Panasonic digital camera. RESULTS AND CONCLUSION: ① With the increasing amount of dispersing agent, the number of polystyrene particles also increased, especially at 0.8 g and 1.0 g dispersant, the number of particles sharply increased, particle size decreases rapidly in the topography. ② Using polyvinyl alcohol alone, the number of particles significantly increased along with the increasing amount of alcohol, the topography showed the particle size decreased sharply, indicating a good dispersion; Using sodium phosphate alone and using a compound dispersant of polyvinyl alcohol and sodium phosphate, the number of particles reduced along with the increase of dispersant, the topography showed that particle size significantly increased. ③ With the increasing times of adding dispersant, the number of polystyrene particles was also increasing under the same quality. The additional times increase may accelerate the dispersion effect of dispersants to some extent. Related Articles | Metrics

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Preparation and properties of 5-Fluorouracil magnetic nanoparticles Wang Jin, Lin You-wen, Wang Ming-na 2010, 14 (47):  8809-8813.  doi: 10.3969/j.issn.1673-8225.2010.47.017 Abstract ( 380 )   PDF (331KB) ( 432 )   Save BACKGROUND: Within a magnetic field, magnetic drug-loaded nanoparticles can implement targeted therapy, reduce systemic side effect. Also serving as a release carrier, magnetic drug microspheres can decrease administration frequency and achieve effective treatment. OBJECTIVE: To prepare 5-Fluorouracil magnetic nanoparticles, and to estimate nanoparticles’ performance. METHODS: Nanometer-sized magnetic release particles were prepared by an emulsifying-complex coacervation method with alginate-chitosan as the coating material, 5-Fluorouracil as model drug, Span80 as emulsifier, liquid paraffin as disperse medium. The shape, stability, magnetic responsiveness, structures, swelling action, release action in vitro of nanoparticles were investigated. RESULTS AND CONCLUSION: The 5-Fluorouracil nanoparticles were spherical shape with a regular surface, fine dispersibility at a diameters of 100-300 nm. They have good stability and good magnetic responsiveness. To investigate the influence of Fe3O4 dosage, with the increase of Fe3O4 dosage, the magnetic responsiveness increased, while the loading capacity increased. The infrared results showed that the nanoparticles encapsulated with Fe3O4, and 5-Fluorouracil interacted with coating materials. The 5-Fluorouracil nanoparticles were immersed in three mediators of distilled water, 0.9% NaCl and phosphate buffer saline (pH=7.4), the hydrating rate and swelling ratios in distilled water were the highest, while the lowest in phosphate buffer saline (pH=7.4). The sustained-releasing ability of nanoparticles was well, and the releasing content counted for 53.20% of total drug within 50 hours. Related Articles | Metrics

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Assemble and biomimetic mineralization of chitosan-phosphorylated chitosan polyelectrolyte complex hydrogel Hen Jun, Li Quan-li, Tang Xu-yan, Zhou Jian 2010, 14 (47):  8814-8817.  doi: 10.3969/j.issn.1673-8225.2010.47.018 Abstract ( 309 )   PDF (392KB) ( 482 )   Save BACKGROUND: Based on the theory of biomineralized organic matrix template controls inorganic crystal growth, human hard tissue repair materials constructed using molecular bionic technology is one of the research hotspots of biological materials. But there is no report regarding polyelectrolyte complex organic matrix plate constructed for biomimetic synthesis of bone tissue repair materials. OBJECTIVE: Polyelectrolyte complex hydrogel formed by reacting polycation chitosan and polyanion derivate phosphorylated chitosan is used as the pre-tissue biomineralized organic matrix template to biomimetic synthesis of the biomaterials. METHODS: Firstly natural polycation polysaccharide chitosan was modified through phosphorylation, to synthesize polyanion derivate phosphorylated chitosan; then polyelectrolyte complex hydrogel was formed from equal volumes of phosphorylated chitosan solution and polycation chitosan solution. The obtained polyelectrolyte complex hydrogel was soaked in supersaturated CA/P solution to induce hydroxyapatite crystals deposit and grow under the regulation of hydrogel matri. It was characterized with fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. RESULTS AND CONCLUSION: The porous polyelectrolyte complex hydrogel formed by the interaction between polycation chitosan and polyanion phosphorylated chitosan can induce hydroxyapatite crystals nucleated and grew on the fiber surfaces of the hydrogel, thus biomimetic synthesizing a new composite biomaterial for bone repairing. Related Articles | Metrics

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In vitro experiment of modified nano-bone adhesive Zhao Zhe, Lei Ming, Xiao De-ming, Xiong Jian-yi, Ma Jing-ye, Xu Yun, Chen Xu-hong, Peng Fu-ning 2010, 14 (47):  8818-8823.  doi: 10.3969/j.issn.1673-8225.2010.47.019 Abstract ( 293 )   PDF (529KB) ( 478 )   Save BACKGROUND: Currently α-cyanoacrylate glue can be used in many clinical fields, but the application is limited in orthopedics due to some shortcomings of the glue itself. OBJECTIVE: To develop a nano-bone adhesive by modifying common medical glue, to evaluate its cytotoxicity and mechanical property.  METHODS: Rabbit bone marrow stromal stem cells were directly implanted with nano-bone adhesive and common medical glue, the growth of these cells on the surface of the two glues was observed by inverted microscope and scanning electron microscope. The extracting solution of the two glues was collected to culture cells. At 0, 6, 12, 18, 24 hours (short-term assay, viability) and 1-7 days (long-term assay, survival), the cells were examined everyday. Standard polyvinyl chloride tubes were cohered by the two glues respectively, to compare their adhesive strength. Their consolidation time on different contract surfaces was also accounted.  RESULTS AND CONCLUSION: After three times of culture medium replacement, the cells can be grow on the surface of nano-bone adhesive and medical glue. Both had some cytotoxicity that was not significant difference. The mechanical strength of nano-bone adhesive was stronger than the medical glue, and the consolidation time of the former was also faster than the latter. The cytotoxicity of modified nano-bone adhesive is not higher than the medical glue, but the mechanical strength and consolidation are more superior. The former also can stimulate the ossification. Related Articles | Metrics

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Expression of basic fibroblast growth factor in biological transition of collagen lattice in vivo Wang Jian-ning, Sun Yu-gang, Xu Jie, Han Liang 2010, 14 (47):  8824-8826.  doi: 10.3969/j.issn.1673-8225.2010.47.020 Abstract ( 282 )   PDF (263KB) ( 293 )   Save BACKGROUND: As a new dermal substitute, acellular dermal matrix (ADM) has been extensively used in repair of tissue defects. But there are no reports about the expression of basic fibroblast growth factor (bFGF) during long-dated biological transition of ADM. OBJECTIVE: To discuss the rule of the bFGF expression in long-dated biological transition of collagen lattice in vivo. METHODS: A total of 21 Wistar rats were applied to prepare ADM. A wound at 2.5 cm×2.5 cm was made to deep fascia surface on left side of spine cord in 84 rats. ADM was transplanted to the back of Wistar rats, while contralateral normal skin served as the control. Samples were acquired at 3, 5, 7, 10 days, 2, 3, 4, 6, 8, 10 weeks, 4, 6, 8, 10 months after operation. The bFGF expression was detected using immunohistochemical method. RESULTS AND CONCLUSION: Expression of bFGF came to appear in 3 days, and reached the peak in 10 days, then became stable in 4 weeks, after 8 weeks the expression of bFGF was the same with normal skin. In the course of long-dated biological transition of ADM, its rebuilding begins from the border of ADM gradually to the center; the rebuilding will become stable at 6-8 weeks after transplantation, then the ADM is considered to be autologous tissue and participates in the metabolic process of normal tissue. Related Articles | Metrics

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Preparation and characterization of folate-conjugated polymeric micelles Zhang Tong, Chen Han, Liu Ling-rong, Li Xue-min, Zhang Qi-qing 2010, 14 (47):  8827-8830.  doi: 10.3969/j.issn.1673-8225.2010.47.021 Abstract ( 348 )   PDF (389KB) ( 679 )   Save BACKGROUND: Polymeric micelles have a solubilization capacity for insoluble drugs and are suitable carriers of anticancer drugs. Surface modification of polymeric micelles with folic acid could facilitate cellular uptake in folate receptor-positive tumor cells.  OBJECTIVE: To prepare and characterize folate-conjugated micelles incorporated with hydrophobic drugs. METHODS: Polymeric micelles containing coumarin 6 were prepared using thin-film hydration method. Coumarin 6, methoxy polyethylene glycol-phosphatidylethanolamine and folate-polyethylene glycol-phosphatidylethanolamine were dissolved in chloroform/methanol and the organic solution was evaporated by rotary evaporator, then the polymer thin-film was developed, followed by vacuum drying overnight. Hepes buffer solution was added to the thin-film and stirred by magnetic stirrer at 50 ℃ for 30 minutes. Meanwhile, plain micelles without folate-polyethylene glycol-phosphatidylethanolamine were also prepared. Plain micelles and folate-conjugated micelles were characterized, including the morphology by transmission electron microscopy, particle size distribution by dynamic light scattering and drug loading and encapsulation efficacy by high-performance liquid chromatography. RESULTS AND CONCLUSION: The size of plain micelles and folate-conjugated micelles was about 60 nm under transmission electron microscopy. The mean particle size of plain micelles and folate-conjugated micelles was about 100 nm by dynamic laser scattering. The drug loading and encapsulation efficacy of micelles was about 0.7% and 15%, respectively. Polymeric micelles have significant solubilization effect for unsoluble drugs, and can be used to evaluate the folate receptor targeting in vitro and in vivo. Related Articles | Metrics

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Biodegradation of polycarbonate polyurethane Tuo Xin-lin, Xia Wei-juan, Cheng Xiao-fei, Wu Ji-gong, Zou De-wei 2010, 14 (47):  8831-8834.  doi: 10.3969/j.issn.1673-8225.2010.47.022 Abstract ( 376 )   PDF (529KB) ( 383 )   Save BACKGROUND: Different polyurethanes vary in biostability. Study on the biostability of polycarbonate polyurethane (PCU) is important to determine the feasibility of polyurethane used as the external capsule of prosthetic disc nucleus pulposus.  OBJECTIVE: To observe the in vitro and in vivo degradation properties of polyether polyurethane (PEU) and PCU with different hard segment contents. METHODS: The in vitro hydrolysis, oxidative degradation and enzymolysis experiments of the polyurethane were performed in simulated environment. The prepared PEU and PCU samples were dipped into PBS and “H2O2/CoCl2 preoxidation-Papain” systems for in vitro degradation study at 37 ℃, and implanted into the back muscle of white rabbits for in vivo degradation experiment. RESULTS AND CONCLUSION: The degradation of PCU is greatly better than PEU, with larger hard segment contents and stronger degradation resistance. PCU is much more biostable than PEU, it’s more suitable for long-time biological implantation. Related Articles | Metrics

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Application of hyaluronic acids for osteoarthritic disease Li Qi, Tang Xin, Pei Fu-xing, Li Jian 2010, 14 (47):  8835-8839.  doi: 10.3969/j.issn.1673-8225.2010.47.023 Abstract ( 248 )   PDF (338KB) ( 536 )   Save BACKGROUND: Hyaluronic acid, a polymer polysaccharide, has a certain effect on the osteoarthritic diseases and has been widely used. But its mechanism is not entirely clear and the specific effect remains disputes. So how to select appropriate patients, appropriate drugs for getting greater efficacy and reducing side effects has become the aims of many scholars. OBJECTIVE: To review the application, underlying mechanism, safety, efficacy, indications and adverse reactions of hyaluronic acid used for osteoarthritic diseases. METHODS: A computer-based online search of CNKI (www.cnki.net) and PubMed database (www.pubmed.com) was performed with key words of “hyaluronic acid, fractures, arthritis” in Chinese and “hyaluronic acid, hyaluronan, osteoarthritis, fracture” in English. RESULTS AND CONCLUSION: Finally, 47 literatures were included for analysis. Hyaluronic acid is safe and effective for osteoarthritic diseases. The main mechanisms are: coverage, lubrication, cushioning cartilage stress; reducing the intra-articular inflammation; promoting the secretion of endogenous hyaluronic acid. Strict control of its indications and selection of suitable molecular weight hyaluronic acid can increase the symptomatic relief and improve treatment satisfaction, while reducing the medical data waster and adverse events. But some problems such as the course of hyaluronic acid treatment, interval and drug selection are still disputable and require further study. Related Articles | Metrics

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Application of nickel-titanium shape memory alloys in orthopedics Yu Yang, Li Xin-zhi, Zheng Zhi-he 2010, 14 (47):  8840-8842.  doi: 10.3969/j.issn.1673-8225.2010.47.024 Abstract ( 429 )   PDF (270KB) ( 902 )   Save BACKGROUND: Nickel-titanium shape memory alloys have been widely applied in many medical fields such as orthopedic internal fixation devices, dentistry, cardiovascular materials, neurosurgery, urology, gastrointestinal surgery, hepatobiliary surgery and reproductive medicine. OBJECTIVE: To review nickel-titanium shape memory alloy in all aspects of orthopedic applications and to clarify the status of its application in orthopedics. METHODS: A computer of CNKI database (2002-2009) and Pubmed database (1963-2009, http://www.ncbi.nlm.nih.gov/ PubMed) was performed by the first author using “nickel titanium shape memory alloy, fracture” in Chinese and English as the key words, to retrieve articles about the application of nickel-titanium shape memory alloy in orthopedics. RESULTS AND CONCLUSION: Totally 57 articles were obtained by the preliminary check, the titles and abstracts were screened, 24 literatures met the inclusion criteria were summarized. The results show that nickel-titanium shape memory alloy is not only used for the fractures in limbs, also used in the spine and femoral head fractures in recent years. Nickel-titanium shape memory alloy has good biocompatibility, and super-flexible, low-magnetic, wear-resistant, fatigue-resistant, corrosion-resistant properties, it has been widely used as a new type of internal fixation materials. Related Articles | Metrics

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Research progress of focal adhesions in cell biomechanics Feng Zhi-yuan, An Xiao-li, Zhang Bao-ping, Ma Hai-bing, Wang Jing, Liu Bin　 2010, 14 (47):  8843-8846.  doi: 10.3969/j.issn.1673-8225.2010.47.025 Abstract ( 294 )   PDF (260KB) ( 481 )   Save BACKGROUND: Focal adhesions have achieved many progresses in the biomechanical field, but the research is still at an early stage, facing the difference between theoretical model and experimental observations, some models lack experimental evidence and further optimizing. OBJECTIVE: To summarize recent research and related progress on focal adhesions biomechanics. METHODS: A computer-based online search of CNKI database from January 1995 to April 2010, PubMed database and Elsevier (ScienceDirect) database from January 1975 to April 2010, was performed with key words of “cell adhesion, focal adhesions, adhesion strength, cell mechanics, molecular bond, flexible interface” both in Chinese and English. Literatures concerning focal adhesions in cell biomechanics were included, repetitive research was excluded. RESULTS AND CONCLUSION: A total of 109 articles were screened out, 64 of them were excluded due to unrelated study objective and repeated contents, finally 45 articles were involved in further analysis. At present, studies on focal adhesions mainly focus on the biomechanical properties of adhesion plaques, the interactions between focal adhesions and cytoskeleton, the size of focal adhesions and adhesion strength, flexible interface and adhesion. With the cell biology, molecular biology and mathematical modeling of the finite element analysis method develop, bio-mechanics study of adhesion plaque will have a new space. Focal adhesion modeling method is further improved and closer to the biological experimental data, the mechanical problems related to focal adhesion is also a new discovery, the focal adhesion biomechanical research can help to establish and analyze other biological micro-models, as well as to understand the mechanism underlying cell adhesion and invasion of tumor cells from the mechanical point of view. Related Articles | Metrics

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Progress in the application of layered double hydroxide in bioengineering Zhao Jian-zhi, Yang Qin-zheng, Zhang Hai-guang 2010, 14 (47):  8847-8849.  doi: 10.3969/j.issn.1673-8225.2010.47.026 Abstract ( 318 )   PDF (248KB) ( 357 )   Save BACKGROUND: Layered double hydroxide is an inorganic nano-material which has the properties of good biocompatibility and biodegradability. At present, many drugs and layered double hydroxide successfully form intercalation compound and obtain expected results. OBJECTIVE: To review research progress and application of layered double hydroxide in bioengineering field. METHODS: A computer search was mainly performed among articles published from 2003 to 2010 with the Chinese and English key words of “nanotechnology, drug carrier, layered double hydroxide, gene, gene therapy, biosensor, targeting drug delivery”, and a library search was carried out as an assist. Researches about application of layered double hydroxide as drug (gene) carrierand biosensor in bioengineering were included. Researches on little related to theme and physicochemical properties about layered double hydroxide were excluded. RESULTS AND CONCLUSION: Research shows that intercalation compound not only controls release, but also improves stability for drugs (genes) with toxic and side-effect, and instable chemical property. So, layered double hydroxide is a “green” carrier material with greatly development potential. But, research on layered double hydroxide in bioengineering is confined to laboratory, and researchers must make hard work for clinical application. Related Articles | Metrics

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Biocompatibility and clinical application of inguinal hernia repair materials Li Guang-xie 2010, 14 (47):  8850-8852.  doi: 10.3969/j.issn.1673-8225.2010.47.027 Abstract ( 247 )   PDF (256KB) ( 410 )   Save OBJECTIVE: To evaluate the clinical application of inguinal hernia repair materials and in vivo histocompatibility after repair, to search for a suitable repair material. METHODS: Using “inguinal hernia, repair materials, wound healing, clinical, tissue compatibility” in Chinese and in English as the key words, a computer search was performed among articles published from January 2000 to December 2009. Articles about the hernia repair materials and inguinal defects repair were included; duplicated research or Meta analysis articles were eliminated. RESULTS: The article discussed the type and the nature of hernia repair materials, the reasonability and benefits of preperitoneal repair method. According to chemical composition of materials science and biological characteristics, hernia repair materials can be divided into non-absorbable materials, absorbable materials and composite materials. The advantages of polypropylene mesh, a non-absorbable material, is large mesh, which is conducive to fibrous tissue ingrowth, to improve the tissue strength and tensile resistance, with good resistance to infection; its disadvantage is hard texture, and can not be separately placed in an abdominal cavity. Absorbable materials can be against the infection and promote the proliferation of collagen. Composite materials may reduce the amount of foreign body (polypropylene), prevent adhesion, and have anti-inflammatory effects. CONCLUSION: The clinical application of hernia repair materials promotes the development of for a variety of tension-free hernia repair. With the emergence of new materials, more patches can be designed according to different physical or biological characteristics of patients. Related Articles | Metrics

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Characteristics and effects of acellular tissue matrix materials to construct tissue engineering vascular stent Li Chun 2010, 14 (47):  8853-8856.  doi: 10.3969/j.issn.1673-8225.2010.47.028 Abstract ( 321 )   PDF (282KB) ( 454 )   Save OBJECTIVE: To evaluate the properties and development prospects of tissue engineering vascular stents. METHODS: A computer search was performed for article published between January 1993 and October 2009, using “tissue engineering, tissue engineering blood vessels, stents” in Chinese as key words. Article about the biomaterials and tissue engineering blood vessels were included; duplicated research or Meta analysis articles were eliminated. The main focus of 26 articles was to discuss the type and properties of tissue engineering blood vessel materials. RESULTS: The vascular acellular matrix can be used as an ideal stent material in vascular tissue engineering. Fibrin stents not only have ideal biocompatibility, biodegradability and high affinity, but also can promote angiogenesis and tissue repair. The gelatin is antigenicity-free, biocompatible and completely biodegradable, it can achieve its own vascularization, but the mechanical strength is low. Natural biomaterials and synthetic polymer materials have certain deficiencies, a matrix compounded the two materials with certain combinations can play their respective advantages and construct tissue engineered blood vessels with good performance. Nano-modification technology is expected to be applied to the next generation of tissue engineered vascular grafts. CONCLUSION: In recent years the tissue engineered blood vessels rapidly develop, but so far there is no an ideal vascular stent. Natural biomaterials become a current research hotspot, but the physical and mechanical properties can not properly meet the requirements of the vascular stents, thus it is eager to emerge new materials which can better meet the requirements of the tissue engineered vascular stents, so as to achieve the purpose of repair and reconstruction. Related Articles | Metrics

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Nano-scaffolds applied in repair of spinal cord injury Yu Peng, Song Zhan-zhao, Sun Pei-feng, Chen Jun, Ju Ping, Sui Yan, Liu Pin-ting 2010, 14 (47):  8857-8860.  doi: 10.3969/j.issn.1673-8225.2010.47.029 Abstract ( 250 )   PDF (295KB) ( 395 )   Save BACKGROUND: As the carrier of seed cells in tissue engineering scaffolds, nano-materials is exerting an increasingly important role in repair of spinal cord injury due to unique effects such as favorable cell adhesion and proliferation. OBJECTIVE: To analyze and summarize the literatures abour spinal cord injury repair using nano-scaffold materials published in recent years, and to search for a suitable nano-material and its applicable standards for spinal cord tissue engineering. METHODS: A computer-based search was performed in September, 2010 by the first author among PubMed database, Wanfang database and VIP database. English data retrieval time was from 2000 to 2009; Chinese data retrieval time was from January 2003 to August 2010. English key words were “nanometer scaffold; materials; spinal cord injury; repair; tissue engineering”; Chinese key words were “nano-scaffold, biomaterials, spinal cord injury, repair, tissue engineering”. Inclusion criteria: ① nano-scaffold preparation technology and properties. ② tissue engineering repair spinal cord injury. ③ animal experiments and clinical applications. After reading and screening, 30 articles were included in the final analysis. RESULTS AND CONCLUSION: Compared with the traditional scaffolds, nano-scaffolds have good bio-degradable performance, no immunogenicity, plasticity and excellent mechanical properties, so that the scaffold is potentially applied in the field of tissue engineering. With the development of nanotechnology, the manufacturing technique optimization, the introduction of genetic engineering, and the scientific evaluation of nano-materials’ safety will be the challenges for future clinical application of tissue engineering nano-scaffold materials. Related Articles | Metrics

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Safety of anti-tumor nano-materials for drug delivery Chen Qing-jiang, Zhang Ming-zhi, Chen Xiao-bing 2010, 14 (47):  8861-8864.  doi: 10.3969/j.issn.1673-8225.2010.47.030 Abstract ( 248 )   PDF (337KB) ( 359 )   Save OBJECTIVE: To introduce the advantages of anti-tumor nano-materials as drug carrier in prolonging the drug persistence in tumor, slowing tumor growth and reducing side effects, to investigate the safety of anti-tumor nano-materials for drug delivery. METHODS: Using “cancer, drug carriers, carrier materials, nanotechnology, targeting” in Chinese and in English as the key words, a computer retrieval of articles between January 1990 and December 2009 was performed. RESULTS: The nano-materials used for anticancer drug delivery include synthetic organic polymer materials, natural biological macromolecules materials and so on, as a drug carrier it can effectively reduce the adverse effects of anticancer drugs and improve its efficacy. Synthetic organic polymer materials have high purity, controllable performance, and good biodegradability, they have become the worldwide development hotspots. Most researches focus on alkyl cyanoacrylate polymer, polylactic acid, polylactic acid polyglycolic acid copolymer, polyamide-dendritic polymers and so on. Natural biological macromolecules chitosan, albumin, gelatin and starch can be used as carrier nanoparticles and exhibit good biocompatibility, biodegradability and low toxicity. CONCLUSION: The nano-material is an ideal carrier for anticancer drugs, it has important scientific value and application, can provide a new and effective means for clinical anti-tumor treatment. Related Articles | Metrics

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Type and clinical application of drug delivery carriers Lao Li-chun 2010, 14 (47):  8865-8868.  doi: 10.3969/j.issn.1673-8225.2010.47.031 Abstract ( 440 )   PDF (335KB) ( 1262 )   Save OBJECTIVE: To describe the clinical application of several important carrier materials. METHODS: Using “drug carrier, sustained-release materials, biodegradable” in Chinese as the key words, China Academic Journal Full-text database (CNKI: 1989/2010) was retrieved online for all relevant literatures. Meta analysis and repeated studies were excluded, and ultimately 20 articles were involved in the final analysis. RESULTS: The biodegradable synthetic polymer materials are safe and reliable, they have good biocompatibility and become a preferred material of drug delivery carriers; as a drug delivery carrier, chitosan plays an important role on reducing delivery times, reducing drug toxicity, and improving drug effect; nanofiber carriers could remarkably enhance the sustained-release of the drugs; fiber protein exhibits good biocompatibility and considered as a good carrier for drug delivery. CONCLUSION: The drug controlled-release system shows many advantages in vivo, such as passive targeting and sustained-release, it is an important component of drug delivery system and the main factors influencing the efficacy. Related Articles | Metrics

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Characteristics of bone tissue engineering scaffold materials for repair of bone defects Yu Meng 2010, 14 (47):  8869-8872.  doi: 10.3969/j.issn.1673-8225.2010.47.032 Abstract ( 286 )   PDF (332KB) ( 554 )   Save OBJECTIVE: To introduce the characteristics of various bone tissue engineering scaffolds and their role in repairing bone defects. METHODS: Using “bone tissue engineering, scaffold, bone defect” in Chinese and in English as the key words, a computer search of articles from January 2000 to June 2010 was performed. Articles related to bone tissue engineering scaffolds to repair bone defects were included. Totally 28 articles focuses on the characteristics of various bone tissue engineering scaffolds in repairing bone defects, and verified using calcium sulfate artificial bone. RESULTS: There are many materials for bone tissue engineering scaffolds, at present, the scaffold materials can be divided into three categories: bio-derived materials, inorganic materials and polymer materials. Each material has its own advantages and disadvantages in the repair of bone defects. With the deepening of the study, a composite scaffold becomes the current research focus. Some bioactive inorganic materials, such as bioactive glass and hydroxyapatite, have been used to prepare novel composite scaffold for bone tissue engineering by adding to collagen and chitosan matrix. Until now, there has no ideal scaffold for bone tissue engineering. Clinical verification shows that calciums sulfate artificial bone is effective in repairing large bone defects. CONCLUSION: It is believed that with the development of various disciplines, the properties of bone tissue engineering scaffold materials will be more perfect, thereby promoting the development of bone tissue engineering, and ultimately apply for clinical application. Related Articles | Metrics

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Tissue engineering scaffold materials repair sports cartilage injury Wang Yong-sheng 2010, 14 (47):  8873-8876.  doi: 10.3969/j.issn.1673-8225.2010.47.033 Abstract ( 223 )   PDF (339KB) ( 436 )   Save OBJECTIVE: To investigate the factors and characteristics of sports cartilage injury, to classify and summarize the selection and application of artificial biomaterial scaffolds in the repair process. METHODS: An online search of PubMed database (http://www.ncbi.nlm.nih.gov/PubMed) and CNKI database (www.cnki.net/ index.htm) was performed by screening the titles and abstracts with the key words of “Cartilage, Damage, Biological Materials, Support, Treatment” in English and in Chinese. Articles related to the treatment, materials science characteristics, biocompatibility and application effect of cartilage scaffolds were selected, these recently published or published in the authority journals were preferred in the same field, finally 26 articles were included in the analysis. RESULTS: Over half a century, the selection and design of cartilage tissue engineering scaffold materials have developed from natural materials, synthetic materials, and other single materials to composite materials. In addition, gene technology, nano-materials and modified technology may provide greater potential and ensure for the healing and rehabilitation of cartilage injury. CONCLUSION: The majority of cartilage injury is caused by sudden violence, and the cartilage cannot repair itself after injury, so cartilage injury is difficult to cure using conventional therapies. With the emergence of tissue engineering, tissue engineering technologies have been gradually applied to cartilage rehabilitation and achieved great success, in particularly the selection and development of cartilage scaffold materials. Single natural materials and synthetic materials have many disadvantages, so the major future direction of scaffold materials research is compound materials, biomimetic materials, and modified materials. With the rapid development and integration of tissue engineering, biological engineering technology and nanotechnology, new composite technology using a variety of materials and technologies will further meet the needs of both doctors and patients. References | Related Articles | Metrics

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Selection of artificial ligament stent and repair of wrist ligament sports injury Zhou Hai-tao 2010, 14 (47):  8877-8880.  doi: 10.3969/j.issn.1673-8225.2010.47.034 Abstract ( 241 )   PDF (361KB) ( 417 )   Save OBJECTIVE: To investigate the wrist ligament injury and selection of ligament stent using artificial biomaterials. METHODS: The PubMed database and CNKI database were retrieved on computer, by screening key words of “wrist joint, ligament, injury, stent” in English and in Chinese in the titles and abstracts. Articles related to wrist ligament injury and treatment, characteristics of materials science, biocompatibility and its application effect were included, those published recently or published in national core journals were preferred in the same field, ultimately 18 articles were involved. RESULTS: The synthetic absorbable scaffold materials may be used as a prosthetic ligament to replace the injured tendon or ligament. LARS artificial ligament imitates the anatomical structure and biomechanical characteristics of the human body, with good resistance to fatigue and not easy to induce inflammation. Treatment of tendon autograft ligament achieves excellent effect for dynamic scapholunate interosseous separation, but poor effect for static scapholunate separation, biological artificial ligament finished product is similar to normal tendon appearance, with flexible texture, reaches a pre-conceived requirement. CONCLUSION: The excellent biocompatibility and resistance to fatigue are essential for the selection of ligament tendon scaffolds, LARS artificial ligament is an ideal graft material, but more suitable for acute ligament injury patients. Ligament tendon autograft is difficult to select. Biological artificial ligament is effective to treat the wrist ligament injury. Cell and molecular biology techniques as well as the use of gene therapy will become a new direction in the treatment of wrist ligament injury and rehabilitation. Related Articles | Metrics

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Application of polypropylene patch in repair of abdominal wall incisional hernia Guo Sheng-qi　　 2010, 14 (47):  8881-8884.  doi: 10.3969/j.issn.1673-8225.2010.47.035 Abstract ( 230 )   PDF (299KB) ( 412 )   Save BACKGROUND: How to repair large defects in abdominal wall is a frequently encountered clinical problem, many scholars have tried to repair using a variety of materials, but the clinical effect is not very satisfactory. OBJECTIVE: To comprehensively analyze the literatures about the application of artificial polypropylene patch to repair the abdominal wall incisional hernia. METHODS: A computer-based search of Pubmed database (http://www.ncbi.nlm.nih.gov/pubmed/) and Wanfang database (http://www.wanfangdata.com.cn) between January 1991 and December 2009 was performed, by screening “patch, surgery, incisional hernia” in English and in Chinese as key words to search the titles and abstracts. Articles related to the artificial material polypropylene patch in repair of abdominal incisional hernia were selected, those recently published literatures or published in the authority journal were preferred in the same field. Eventually 28 articles met the criteria were involved. RESULTS AND CONCLUSION: The large abdominal wall defects often require clinical use of appropriate materials, in order to maintain muscle tension and shape of the abdominal wall. Polypropylene patch has good biocompatibility, and no wound infection, rejection and other complications occur after implantation, the patch is effective to prevent postoperative incisional hernia of free transverse rectus abdominis myocutaneous flap, while enhancing abdominal walll strength. Clinical studies have shown its good tissue compatibility, no rejection, certain resistance to infection, is the ideal material of hernia repair. Hernia repair using artificially synthetic materials is easy to operate, with less damage, quick recovery, low recurrence rate and few complications. The key of related study should focus on the increase of repair techniques, selection and development of the patch with great resistant to tensile strength, mild inflammation, and high compliance. Related Articles | Metrics

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Biphasic ceramic-like bioactive bone compounded by bone morphogenetic protein and basic fibroblast growth factor to repair finger bone defects Wang Fu-ke, Li Yan-lin, Wang Guo-liang Cao Bin, Li Xiao-lin, Chen Jian-ming, Jin Yao-feng, Wang Yong-nian 2010, 14 (47):  8885-8888.  doi: 10.3969/j.issn.1673-8225.2010.47.036 Abstract ( 303 )   PDF (348KB) ( 367 )   Save BACKGROUND: Biphasic ceramic-like bioactive bone compounded bone morphogenetic protein (BMP) and basic fibroblast growth factor (bFGF) has bone conduction function, it can induce stem cells to differentiate into osteoblasts and have become one of ideal bone graft substitutes for repairing bone defects. OBJECTIVE: To explore the biphasic ceramic-like bioactive bone complex of BMP and bFGF in the clinical repair of bone phalanx defect. METHODS: Ten enchondroma patients, at a mean age of 33 years were selected. The tumor size was from 0.3 cm × 0.3 cm × 0.3 cm to 1.0 cm × 0.5 cm × 0.5 cm; tumors were located in the affected finger bone and performed tumor curettage, tumor cavities were stuffed with biphasic ceramic-like bioactive bone, followed by conventional wound suture; The postoperative wound healing, local inflammation, rejection, systemic toxicity, tumor cavity healing and recovery of limb function were observed after operation. RESULTS AND CONCLUSION: No postoperative wound infection, incisal opening healed well. Mild local inflammatory response was observed, with no rejection or systemic toxicity. All patients were followed up for 6 months, new bone grew into the complex BMP and BFGF biphasic ceramic-like bioactive bone filling areas at 3 months after surgery. Fingers could complete daily activities after 1 month. The complex BMP and BFGF biphasic ceramic-like bioactive bone has good osteogenesis, biological security and compatibility, can be used to repair bone defects. Related Articles | Metrics

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Nano-hydroxyapatite/polyamide 66 artificial vertebrae implantation for vertebral reconstruction He Bin, Jiang Dian-ming, Ou Yun-sheng, Quan Zheng-xue, Tang Ke 2010, 14 (47):  8889-8892.  doi: 10.3969/j.issn.1673-8225.2010.47.037 Abstract ( 296 )   PDF (271KB) ( 361 )   Save BACKGROUND: Thoracolumbar vertebral eosinophilic granuloma is uncommonly encountered in clinical practice. Vertebral body replacement with different biological materials is used for the reconstruction of the osseous defect after corpectomy. But it has been few researched about the nano-hydroxyapatite/polyamide 66 artificial vertebral body in the clinical application of the disease until now. OBJECTIVE: To observe the efficacy of nano-hydroxyapatite/polyamide 66 artificial vertebral body on the vertebral reconstruction of eosinophilic granuloma after corpectomy. METHODS: Fifteen patients with thoracolumbar vertebral eosinophilic granuloma confirmed by pathological detection were admitted to Department of Orthopedics at the First Affiliated Hospital of Chongqing Medical University from January 2005 to December 2009, their therapeutic effects were retrospectively analyzed. All the cases underwent anterior lesions removal, implantation of nano-hydroxyapatite/polyamide 66 artificial vertebral body, and anterior screw-plate fixation system. The incision healing, wound complication and recovery of spinal cord function were determined. RESULTS AND CONCLUSION: All 15 patients followed up for a mean of 2.1 years, all of them were cured without recurrence and complications. The spinal cord function recovered. After removal of vertebral eosinophilic granuloma, implantation of nano-hydroxyapatite/polyamide 66 artificial vertebral body, and anterior screw-plate fixation system can obtain good therapeutic effect of vertebral reconstruction. Related Articles | Metrics

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External application of methotrexate flexible nanoliposomes in treatment of rheumatoid arthritis Fan Rong, Liang Qing-hua, Wang Juan, Xiong Xin-gui, Chen Jiang 2010, 14 (47):  8893-8896.  doi: 10.3969/j.issn.1673-8225.2010.47.038 Abstract ( 285 )   PDF (323KB) ( 429 )   Save BACKGROUND: Studies have shown that external application of methotrexate can increase local drug concentration, with good efficacy and fewer systemic side effects. The current external formulations are creams, plastics, pellicles and so on, but the percutaneous absorption is not satisfactory. Developing a drug-laded flexible nanoliposome with excellent transdermal permeability, would greatly expand the applicable scope of transdermal drug delivery. OBJECTIVE: To investigate the effectiveness of flexible nanoliposomes of methotrexate for external application in the treatment of rheumatoid arthritis and to evaluate the adverse effect. METHODS: Based on routine rheumatoid arthritis therapy, 44 patients with rheumatoid arthritis were divided into a treatment group with flexible nanoliposomes of methotrexate and a control group with methotrexate pill for 12 weeks. The clinical indices including joint tenderness index, joint swelling index, joint dysfunction index, morning stiffness time and average gripping strength were observed. The safety of flexible nanoliposomes of methotrexate was also assessed. RESULTS AND CONCLUSION: After 12 week of the therapy, flexible nanoliposomes of methotrexate could significantly reduce the joints pain and tenderness compared with methotrexate pills, and the effective rates in treatment group and control group were respectively 90% and 75% with no significant differences between two groups (P > 0.05). Further, the side effects of treatment group were significant lower than control group (P < 0.01). Both external application of flexible nanoliposomes of methotrexate and the oral administration of methotrexate pills could significantly improve the clinical signs and symptoms of rheumatoid arthritis patients. But the former is better than the latter in the aspect of improving the pain, tenderness and swelling of involved joints. Moreover, flexible nanoliposomes of methotrexate has nearly no side effects. Related Articles | Metrics

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Efficacy comparison of fresh amnion and biological amnion transplantation for the treatment of early eyeburn injuries Jin Ke 2010, 14 (47):  8897-8900.  doi: 10.3969/j.issn.1673-8225.2010.47.039 Abstract ( 313 )   PDF (354KB) ( 554 )   Save BACKGROUND: Amniotic membrane transplantation has been commonly used in ocular surface reconstruction, it provides a new means for the treatment of early chemical injuries in eyes. But the specific choice of amniotic membrane has not yet standardized, its clinical results reported have some differences. OBJECTIVE: To compare the clinical efficacy of fresh amnion and biological amnion transplantation for the treatment of early eyeburn injuries. METHODS: A total of 66 patients (66 eyes) with early burn injuries were randomly divided into fresh amnion group and biological amnion group, with 33 cases in each group, they received fresh amnion transplantation and biological amnion transplantation respectively. All patients were followed up for 3 months after surgery, and the visual acuity, graft survival, complications were observed and compared. RESULTS AND CONCLUSION: The postoperative visual acuity of both groups improved significantly (P < 0.05); there were 2 cases and 3 cases of fresh amnion group and biological amnion group respectively occurred early dissolution and loss of amnion, and they were cured after the second transplantation. The incidence of complications such as keratoleukoma, corneal macula and corneal neovascularization had no significant difference between the two groups (P > 0.05). Both fresh amnion and biological amnion transplantation can be effective for the treatment of early ocular injuries and ocular surface reconstruction, the efficacy has no significant difference between the two methods. Related Articles | Metrics

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Hydroxyapatite artificial eye implantation in 25 cases: A comparison of traditional method and improved method Zhang Xiao-guang, Liu Xiao-qin, Zhou Qi, Wu Jiang 2010, 14 (47):  8901-8903.  doi: 10.3969/j.issn.1673-8225.2010.47.040 Abstract ( 225 )   PDF (213KB) ( 356 )   Save BACKGROUND: With improvement of artificial eye material, the method of artificial eye implantation is critical for artificial eye exposure. OBJECTIVE: To study a new method of hydroxyapatite (HA) artificial eye implantation with less complications after surgery than the common operation, and to explore the mechanism underlying artificial eye exposure after eye content enucleation and HA artificial eye implantation, so as to elevate the treatment standard. METHODS: Twenty-five patients were divided randomly into two groups according to surgical approach. In traditional approach group, 14 patients (14 eyes) were treated with eye enucleation and HA artificial eye implantation, while in modified approach group, 11 eyes underwent eye enucleation and double-sclera covered hydroxyapatite implantation in muscle cone. The rates of artificial eye exposure and materials-host reaction were compared and analyzed between two groups. RESULTS AND CONCLUSION: Artificial eyes of traditional approach group were exposed in 8 cases, and that of modified approach group was exposed in 1 case. There were significant differences between the two group by correct Chi-square test  (χ2=4.264, P=0.039 < 0.05). Modified HA artificial eye implantation is a good method with simple operation and less artificial eye exposure. Related Articles | Metrics

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Effect of two light-curing modes on marginal adaptation and microhardness of packable posterior resin-based composites Yang Jun-ying, Zhang Sheng-yan, Chen Shan, Feng Lei 2010, 14 (47):  8904-8908.  doi: 10.3969/j.issn.1673-8225.2010.47.041 Abstract ( 280 )   PDF (295KB) ( 651 )   Save BACKGROUND: The use of resin-based composites is increasing in clinical practice. The success and longevity of composite-resin restorations highly depends on adequate polymerization and small polymerization shrinkage, which are closely related with light-curing modes. OBJECTIVE: To investigate the effects of two different light-curing methods on marginal adaptation and microhardness of packable posterior composite restorations. METHODS: Specimens were made from these moulds with 3 types of packable resin-based composites: Ecusphere-Carat, 3M Filtek P60 and Tetric Ceram HB, and 2 curing modes: standard and soft-start curing mode with halogen light. The marginal adaptation was evaluated by measuring the width of margin gap between the mold and specimens with scanning electron microscope. Vickers microhardness was tested on the top and bottom surfaces of the specimens. RESULTS AND CONCLUSION: For Filtek P60 and Tetric Ceram HB, soft-start curing mode showed lower values of the widths of marginal gap than that of standard mode (t=5.78, P < 0.05; t=5.64, P < 0.05), but there was no significant difference with Ecusphere-Carat (t=1.62, P > 0.05). The top surface demonstrated higher microhardness values than the bottom surface in all experimental conditions (P < 0.05). The soft-start curing mode showed lower values of top surface hardness for the three resins than that of standard mode (P < 0.05). But no significant differences were found on the bottom surface hardness of the three resins between these two curing modes (P > 0.05). Compared with routine light-cured mode, the soft-start curing mode can reduce the polymerization shrinkage and surface hardness of packable resin-based composites. Related Articles | Metrics

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Application of polypyrrole-based biomaterials in tissue engineering Fan Jian-ping, Xie Ai-ni, Liu Cheng-gui, Zhang Kai-lun 2010, 14 (47):  8909-8915.  doi: 10.3969/j.issn.1673-8225.2010.47.042 Abstract ( 274 )   PDF (284KB) ( 589 )   Save BACKGROUND: Polypyrrole (PPy) has been widely applied in biomedical fields due to its special electronic property. Past 20 years, there are an increasing number of studies on the application of PPy as a potentially electrically addressable tissue/cell support substrate for tissue/cell regeneration. OBJECTIVE: To overall review the application of PPy in tissue engineering field, and to provide a new approach for the research and development of medical biomaterials. METHODS: Pubmed and Chinese biomedicine literature database were searched using key word of “polypyrrole” for documents published between 1990 and 2010. Literatures related to application of PPy in tissue engineering field were included, and the repetitive articles were excluded. RESULTS AND CONCLUSION: Totally 762 papers were searched by computer, according to the inclusive and exclusive criteria, 51 literature were reviewed. Currently, PPy has been widely used in the fields of cardiovascular tissue engineering, bone and muscle tissue engineering, as well as skin tissue engineering. Application of PPy and PPy-based biomaterials hold great potential in development of novel biomedical materials applied in tissue engineering due to their versatile functionality and superior biocompatibility. Related Articles | Metrics

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Interferon/poly (lactic-co-glycolic acid) and chitosan/poly (lactic-co-glycolic acid) composite membranes for prevention of epidural scar adhesion following laminectomy Su Yun, Meng Xiang-jun, Zhang Xin 2010, 14 (47):  8916-8920.  doi: 10.3969/j.issn.1673-8225.2010.47.043 Abstract ( 259 )   PDF (365KB) ( 381 )   Save BACKGROUND: Epidural resistance materials are an approach to prevent the epidural scar adhesion after laminectomy. A composite membrane of mechanical separation and fibroblast inhibition is promising to be widely studied. OBJECTIVE: To prepare the interferon (IFN)/poly (lactic-co-glycolic acid) (PLGA) and chitosan/PLGA composite membranes, and to observe their effects on preventing epidural scar adhesion after laminectomy in rabbits. METHODS: L2 laminectomy was performed in 120 rabbits, which were randomly and evenly divided into six groups. The control group received nothing on epidurals. In the autologous free fat group, the exposed dura was covered with subcutaneous fat. In the sodium hyaluronate group, 1 mL sodium hyaluronate was dripped onto the dura. In the PLGA, chitosan/PLGA, and IFN/PLGA groups, the exposed dura was covered with one of the three membranes at a sufficient size. The animals were sacrificed at 2, 4, 6, 8 weeks postoperatively. The scar formation and adhesion to the dura in L2 laminectomy sites were observed and scored by gross observation. At 4 weeks postoperatively, fibroblast ultrastructure was observed through the use of transmission electron microscope. RESULTS AND CONCLUSION: Widespread scars formed in the control group. The scars in the autologous free fat and PLGA groups were less compared with the control group, but there was no significant difference between these two groups. In the early stage, the scars in the sodium hyaluronate group were obviously less compared with the autologous free rat and PLGA groups, while in the later period, the difference between them was not significant, but the results from the sodium hyaluronate group were still better compared with the control group. The scars and slight adhesion to the dura were observed in the chitosan/PLGA and IFN/PLGA groups. The effect of preventing scar adhesion in these two groups was remarkably superior to that in the other groups, but there was no significant difference between these two composite membrane groups. At 4 weeks postoperatively, fibroblast morphology and function in the control, autologous free rat, and PLGA groups were better than those in the chitosan/PLGA and IFN/PLGA groups. Chitosan/PLGA and IFN/PLGA composite membranes are effective materials to prevent epidural scar adhesion after laminectomy. Related Articles | Metrics

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Acellular porcine aorta matrix as a novel tissue engineered vascular scaffold Biocompatibility and mechanical properties Lü Yu-ming, Huang Hua-mei, Wang Qiu-ling, Xie De-ming 2010, 14 (47):  8921-8926.  doi: 10.3969/j.issn.1673-8225.2010.47.044 Abstract ( 264 )   PDF (610KB) ( 518 )   Save BACKGROUND: The key of tissue engineered blood vessel research depends on the appropriate scaffolds. The porcine vascular tubes have frequently been used as candidates for tissue engineering vessel construction, but high immunogenicity and poor mechanical strength limit its application for tissue engineering scaffolds. OBJECTIVE: To prepare a novel tissue engineered vascular scaffold with good mechanical properties and biocompatibility using acellular porcine aorta matrix. METHODS: Porcine aorta was decellularized and modified by thermal cross-linking to improve the mechanical strength and biodegradation properties and to prepare acellular porcine aorta matrix scaffolds. Hematoxylin-eosin staining of histological sections and biomechanical tests were performed to assess the decellularization effects and the mechanical strength of the vascular matrix respectively. Vascular endothelial cells from human umbilical cord veins were isolated and seeded on the acellular matrix scaffolds and cultured in vitro. The biocompatibility was evaluated. RESULTS AND CONCLUSION: After the porcine aorta was treated by 1% Triton X-100 solution for 84 hours, the vessel was fully decellularized, and the architecture of matrix was well preserved. The acellular vascular matrix demonstrated improved biomechanical properties after modification by thermal cross-linking under vacuum at 120 °C for 12 hours. Its tensile strength reached 1.70 MPa. After 7 days of in vitro culture, the seeded endothelial cells formed a typical vascular endothelial layer structure on the surface of acellular matrix, as observed by scanning electron microscopy. Results proved that acellular vascular matrix of porcine aorta could maintain the morphology and structure of natural vessels, its mechanical strength could be greatly improved after successive freeze-drying and thermal cross-linking. A good compatibility between the acellular matrix and endothelial cells of umbilical vein is also achieved. Related Articles | Metrics

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Effects of fibrin gel combined with basic fibroblast growth factor on alkaline phosphatase activity in fetal rat limb cells Wang Ying-hui, Chen Li, Mai Xia, Zha La Ga Hu, Chen Xiao-yi 2010, 14 (47):  8927-8930.  doi: 10.3969/j.issn.1673-8225.2010.47.045 Abstract ( 271 )   PDF (640KB) ( 370 )   Save BACKGROUND: Fibrin is a natural biodegradable polymer material with good histocompatibility. Basic fibroblast growth factor (bFGF) is an important polypeptide growth factor with mitogenic effect. Fibrin gel (FG) combined with bFGF is conducive to cell migration and promotes proliferation and differentiation. OBJECTIVE: To investigate the effects of fibrin gel combined with bFGF on alkaline phosphatase activity (ALP) in fetal rat limb cells. METHODS: Four groups were included: FG group: fetal rat limb cells were seeded in FG (three-dimensional, 3D) with normal medium; FG + bFGF group: cells were seeded in FG containing 10 μg/L bFGF for 24-hour 3D culture; bFGF group: cells were seeded in 10 μg/L bFGF medium; normal control group: cells were seeded in normal culture medium. Under aseptic condition, rat fetal limb cells were isolated. Passage 3 cells were used for each group above mentioned. ALP activity, mRNA expression and cell morphology were analyzed at 3, 5, 7, 14, 21, and 28 days after culture. RESULTS AND CONCLUSION: The cells in the FG had more processes and formed an interconnected network after 7 days of incubation, while the cells in no gels remained cuboidal or “spindle-shaped”. At 7, 14, and 21 days, ALP activity was greater in the FG+ bFGF group than in the other groups (P < 0.05). At each time point, mRNA expression of ALP was greater in the FG+ bFGF group than in the control group (P < 0.01). These findings indicate that FG combined with bFGF is conducive to cell morphogenesis and markedly enhances ALP activity. Related Articles | Metrics