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    21 May 2011, Volume 15 Issue 21 Previous Issue    Next Issue
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    Tissue engineered periosteum fabricated using bone marrow mesenchymal stem cells and small intestinal submucosa
    Wang Jun-sheng, Wang Shuan-ke, Chen Xing-li, Hu Xiao-wu
    2011, 15 (21):  3801-3804.  doi: 10.3969/j.issn.1673-8225.2011.21.001
    Abstract ( 106 )   PDF (1430KB) ( 319 )   Save

    BACKGROUND: Periosteum has been confirmed to repair bone defects in large number of experiments. But its source is limited, thus restricting clinical applications. Therefore, artificial periosteum constructed using tissue engineering principles and methods is worthy of further exploration and research.
    OBJECTIVE: To explore the practicability of tissue engineered periosteum fabrication by small intestinal submucosa as a tissue scaffold with rabbit bone marrow mesenchymal stem cells (BMSC).
    METHODS: Bone marrow was obtained from healthy New Zealand rabbits, by using density gradient centrifugation BMSCs were isolated and were then cultured in vitro. Following induced differentiation and identification, the BMSCs were compounded with porcine small intestinal submucosa to fabricate tissue engineered periosteum. The adhesion, growth, proliferation of BMSCs on the materials, as well as extracellular matrix secretion were observed.
    RESULTS AND CONCLUSION: The BMSCs by osteogenic induction could quickly adhere and proliferate on the surface of porcine small intestinal submucosa and got into the holes. Meantime, BMSCs secreted a great deal of extracellular matrices. BMSCs grew well there in layers, and the periosteum became thicker as time passed, acting like a biological periosteum. Combined culture of porcine small intestinal submucosa and BMSCs can construct a tissue engineering periosteum with physiological function.

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    In vivo degradation of beta-tricalcium phosphate/poly-l-lactide composites in cancellous bone
    Wang Xiao, Liu Yu-jie, Chen Xu
    2011, 15 (21):  3807-3810.  doi: 10.3969/j.issn.1673-8225.2011.21.003
    Abstract ( 218 )   PDF (1239KB) ( 508 )   Save

    BACKGROUND: To improve the degradation and osteoinductive property of Poly-L-lactide (PLLA) materials, adding inorganic particles such as hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) is a popular choice.
    OBJECTIVE: To investigate the in vivo degradation and osteoinductive property of β-TCP/PLLA and PLLA materials in cancellous bone comparatively.
    METHODS: Totally 12 adult New Zealand rabbits were implanted PLLA andβ-TCP/PLLA materials into medial and lateral femoral condyle on both sides respectively. The rabbits were sacrificed separately at 6, 12, 24 weeks after operation, 4 animals at each time. The bioabsorption rate, light microscopic and scanning electron microscopic images of PLLA and β-TCP/PLLA materials and surrounding bony tissues were investigated.
    RESULTS AND CONCLUSION: β-TCP/PLLA composites contacted more closely with surrounding bone tissues than PLLA. No foreign body reaction was observed. The bioabsorption rate of β-TCP/PLLA that was slower than PLLA in the first 6 weeks accelerated after this period, while more micropores and fine groove in the surfaces and inner part of β-TCP/PLLA composites were observed. No bony replacement was observed in 24 weeks postoperatively. The results show that the degradation rate of β-TCP /PLLA composites that are slower than PLLA in early stage speed up after this period, which is propitious to stablize fixation of implants. Tissue compatibility of β-TCP /PLLA composites is better than PLLA. However, no osteoinductive property of both materials is observed during the study periods.

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    Adhesion and proliferation of osteoblasts on the surface of titanium alloy modified by chitosan-casein phosphopeptides
    Wang Lin, Bu Yin-zhong, Wang Jin-qing, Yang Sheng-rong, Liu Bin
    2011, 15 (21):  3811-3814.  doi: 10.3969/j.issn.1673-8225.2011.21.004
    Abstract ( 202 )   PDF (1241KB) ( 420 )   Save

    BACKGROUND: The surface of titanium alloy only absorbs some organic molecule to activate the growth factor and stimulate cell proliferation, thereby activating the surrounding bone cells and producing a marked effect.
    OBJECTIVE: To prepare a bioactive coating on the surface of the titanium alloy implant, and to evaluate one promising strategy to enhance osseointegration.
    METHODS: The surface of titanium alloy modified by silane coupling agent was covalently grafted with chitosan (CS) and the concentration of 0, 5, 10 g/L casein phosphopeptides (CPP) in turn to form composite coatings using multi-step assembly method, compared with unmodified titanium alloy. The biocompatibility of the fabricated coatings was evaluated through co-culture of the titanium alloy and osteoblasts that modified through different procedures, using cell counting, fluorescence staining, and MTT colorimetric assay.
    RESULTS AND CONCLUSION: Compared with the titanium alloy without modification, the early adhesion and proliferation of surface of titanium alloy were significantly increased after CS covalently grafted with CPP (P < 0.05). Moreover, with the increase of CPP concentration, the promotion enhanced significantly (P < 0.05). (The osteoblasts on the surface of titanium alloy without modification displayed smooth surface, clear boundary, not fully stretched; the osteoblast cell body of the surface of titanium alloy increased significantly, rough surface, fuzzy boundaries, and fully stretched after modification by CS -CPP composite coating). It is indicated that the prepared CS-CPP composite coating can significantly increased the function of osteoblasts, improve biological properties of titanium alloy, and expected to be an effective method to promote osseointegration.

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    Effect of calcium acid phosphate and calcium sulfate on tendon-bone healing
    Ni Feng, Huangfu Xiao-qiao, Zhao Jin-zhong, Sha Lin, Xie Guo-ming
    2011, 15 (21):  3815-3821.  doi: 10.3969/j.issn.1673-8225.2011.21.005
    Abstract ( 114 )   PDF (1657KB) ( 465 )   Save

    BACKGROUND: The reports are related to the promotion of tendon-bone healing are many, the main method is to give tendon-bone gap some excitor substance, so as to promote tendon-bone healing. Calcium acid phosphate as bioactive material has bone conductibility, and has been commonly used in substitution and padding of clinical bone defect. However, calcium sulfate as artificial material has potential osteoinductivity.
    OBJECTIVE: To observe the effect of calcium acid phosphate and calcium sulfate on tendon-bone healing during the process of anterior cruciate ligament of knee joint constructed with autologous hamstring tendon transplantation.
    METHODS: A total of 36 male Beagle dogs were selected, and treated with cut off bilateral anterior cruciate ligament, the tendon of flexor digitorum longus was obtained. Suspended fixation method was used to reconstruct anterior cruciate ligament; which were randomly divided into 3 groups: calcium acid phosphate group, calcium sulfate group and blank group. Calcium acid phosphate was injected into femoral tendon bone tunnel in calcium acid phosphate group. Calcium sulfate was injected into calcium sulfate group. No additional treatment was applied to blank group after ligament reconstruction. Dogs were undergoing general observation, histological examination and biomechanical test at 1, 2, 3, 4, 6 months after reconstruction.
    RESULTS AND CONCLUSION: Tendon-bone interface fibronectin in calcium acid phosphate group and calcium sulfate group was significantly better than that in blank group at 1, 2, 3, 4 months after reconstruction of anterior cruciate ligament. There was no significant difference between calcium acid phosphate group and calcium sulfate group. The healing degree in each group was similar after 6 months. In biomechanics, the pull-off strength of tendon-bone interface in calcium acid phosphate group and calcium sulfate group was higher than that in blank group (P < 0.05). However, there was no significance between calcium acid phosphate group and calcium sulfate group (P > 0.05). It is indicated that calcium acid phosphate and calcium sulfate can promote tendon-bone healing, and there was no significant difference between two groups.

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    Bone marrow mesenchymal stem cells differentiation into chondrocytes under growth factor composing allogeneic decalcified bone matrix
    Xu Bin, Xuan Tao, Xu Hong-gang, Wang Hao
    2011, 15 (21):  3822-3828.  doi: 10.3969/j.issn.1673-8225.2011.21.006
    Abstract ( 104 )   PDF (2143KB) ( 365 )   Save

    BACKGROUND: Effective repair of articular cartilage defects and achieving a good long-term efficacy using tissue engineering methods remain unclear. The research group proposed an experimental hypothesis that “allogeneic bone marrow mesenchymal stem cells in articular cavity culture tissue engineered cartilage”.
    OBJECTIVE: To demonstrate the role of allogeneic decalcified bone matrix combined transforming growth factor β1 and insulin-like growth factor Ⅰ to differentiate bone marrow mesenchymal stem cells (MSCs) into cartilage, and to investigate the method of promoting differentiation into articular cartilage by the culture in articular cavity.
    METHODS: Bone marrow MSCs were separated and cultivated in vitro. In experimental group, transforming growth factor β1 and insulin-like growth factor Ⅰ were applied into DMEM to induce proliferation and chondrogenic transformation, while in control group only DMEM was used. The proliferation and chondrogenic transformation between two groups were compared. Allogeneic decalcified bone matrix was prepared, bone marrow MSCs in the experimental group were seeded into the decalcified bone matrix, to construct tissue engineered cartilage complex, which was then place into knee cavity of 30 rabbits after parceled with fascia. At 4, 8, 12 weeks following implantation, ten specimens were selected for histological section observation and type Ⅱ collagen immunohistochemistry staining.
    RESULTS AND CONCLUSION: Colony forming efficiency in experimental group was significantly higher than that of control group (u=3.326, P < 0.01). Immunohistochemical identification of type Ⅱ collagen was positive in experimental group, while negative in control group. At 12 weeks after the tissue engineered complex were cultured, hematoxylin-eosin staining showed that a large amount of chondrocytes began to proliferate, caryon was stained blue. Toluidine blue staining showed that the chondrocytes aligned, there were plenty of cartilage lacunas, and were surrounded by lots of extracellular matrix. Immunohistochemical identification of type Ⅱ collagen was strongly positive, lots of brown-yellow stained particles could be discerned in extracellular matrix. Bone marrow MSCs proliferation and differentiation into chondrocyte can be significantly promoted by the synergistic action of transforming growth factorβ1 and insulin-like growth factor Ⅰ. MSCs combine with decalcified bone matrix can successfully cultivate tissue engineered cartilage in articular cavity. Allogeneic decalcified bone matrix may satisfy the demands of tissue engineered cartilage scaffold.

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    Tissue engineered cartilage constructed by acellular porcine small intestinal submucosa scaffold combined with autologous chondrocytes
    Wu Di, Xie Yu, Wang Shao-yun, Zhu Xiao-song, Li Qing, Dong Jian, Li Shi-he
    2011, 15 (21):  3829-3833.  doi: 10.3969/j.issn.1673-8225.2011.21.007
    Abstract ( 119 )   PDF (1699KB) ( 328 )   Save

    BACKGROUND: It is difficult to achieve a satisfactory repair effect on articular cartilage injury with or without intervention.
    OBJECTIVE: To study the feasibility of constructing tissue engineered cartilage using cultivated the autologous chondrocytes combined acellular porcine small intestinal submucosa (SIS) scaffold.
    METHODS: The third-generation chondrocytes from porcine knee joint were incubated on porcine SIS and cultured for 48 hours to construct a chondrocyte-scaffold complex. The growth of chondrocytes on the scaffold was observed under light microscope and scanning electron microscope.
    RESULTS AND CONCLUSION: Hematoxylin-eosin staining results showed that the chondrocytes presented monolayer or multilayer growth on the surface of the SIS scaffold. Immunohistochemistry staining results showed that there was a successive positive expression strap between the chondrocytes and SIS. Under the scanning electron microscope, the cells adhered to the SIS scaffold grew well.

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    Cell biocompatibility of a new-type nanofiber scaffold for tissue engineering
    Cao Xi-ying, Weng Guo-xing, Xiao Rong-dong, Liu Hai-qing, Wang Jiang-nan
    2011, 15 (21):  3834-3838.  doi: 10.3969/j.issn.1673-8225.2011.21.008
    Abstract ( 70 )   PDF (1404KB) ( 407 )   Save

    BACKGROUND: High-porosity polycaprolactone (PCL) nanofiber scaffolds have a good multi-pore structure for the adhesion and proliferation of vascular smooth muscle cells and perfect biocompatibility.
    OBJECTIVE: To evaluate the cell biocompatibility of high-porosity PCL scaffold made by electrostatic spinning technology.
    METHODS: Electrostatic spinning technology was used to produce high-porosity PCL nanofiber stents. WST-1 method was used to evaluate the effects of scaffold on the adhesion and proliferation of smooth muscle cells cultured with different scaffolds. Light microscope and scanning electron microscope were used to observe the morphology of cells.
    RESULTS AND CONCLUSION: The high-porosity PCL scaffold exhibited better biocompatibility than the traditional one in cell morphology, adhesion and proliferation. It is indicated that the high-porosity PCL nanofiber stents produced by electrostatic spinning technology owns better biocompatibility.

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    Biocompatibility of energied copolyesters coating for magnesium alloy evaluated by cell culture assay
    Pan Feng, Bai Shu-ling
    2011, 15 (21):  3839-3842.  doi: 10.3969/j.issn.1673-8225.2011.21.009
    Abstract ( 118 )   PDF (1360KB) ( 333 )   Save

    BACKGROUND: Compared with polylactic acid (PLA), polyglycolic acid (PGA) and PLA-PGA, 3-hydroxybutyrate-co-3 - hydroxyhexanoate copolyesters (PHBHHx) has structural diversity, good biocompatibility, biodegradability and hot-working character.
    OBJECTIVE: To evaluate the biocompatibility of PHBHHx at different ferulic acid mass concentration by cell culture assay.
    METHODS: Acetic ether was used to prepare films with 0 (control group), 50, 100, 130, 150 g/L ferulic acid PHBHHx and the appearance of films was observed. MTT test, fluorescence microscope and scanning electron microscope were used to assess the growth of bone marrow mesenchymal stem cells surface.
    RESULTS AND CONCLUSION: PHBHHx with 50 g/L ferulic acid showed a lucent film without white crystalline precipitates, but obvious white crystalline precipitates distributed in films formed by PHBHHx with 100, 130, 150 g/L ferulic acid. MTT test indicated PHBHHx with 50, 100 g/L ferulic acid could better promote the growth of bone marrow mesenchymal stem cells. The adhension of bone marrow mesenchymal stem cells in the surface of PHBHHx with 50g/L ferulic acid could be seen under fluorescence microscope and scanning electron microscope. PHBHHx with 50 g/L ferulic acid is the most appropriate coating for magnesium alloys.

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    Preparation and biocompatibility of new heterogeneous acellular nerve of squid
    Fan Wei-jie, Ding Zhi-qing, Xu Xue-mei
    2011, 15 (21):  3843-3846.  doi: 10.3969/j.issn.1673-8225.2011.21.010
    Abstract ( 74 )   PDF (1548KB) ( 340 )   Save

    BACKGROUND: Acellular nerves of mammals have disadvantages: ①The diameter of myelinated fiber is small ; ②The cellular components are difficult to eliminate ; ③The cells are uneven when the acellular nerves are made into tissue engineering nerve.
    OBJECTIVE: To prepare a new kind of squid acellular nerve and to explore its biocompatibility.
    METHODS: The acellular nerves of squid were prepared by chemical methods (Haase chemical extraction). The effects of cells removed were estimated. The integrity of the nerve fiber tube and Schwann cell basilar membrane was observed. The compatibilities of acellular nerves of squid and cells were detected by MTT assay. Its histocompatibility was observed by subcutaneous implantation experiment.
    RESULTS AND CONCLUSION: The cells and myelin of acellular squid nerve prepared by Haase chemical extraction had been cleared completely, and the integrity of the nerve fiber tube and Schwann cell basilar membrane had been remained, and the tube of nerve fiber were large. Subcutaneous implantation results indicated that inflammatory cells expressed around the material at 1 week, 2 weeks after implantation, and thin fibrous connective tissue capsule appeared around the material at 4 weeks after implantation, and few inflammatory cells expressed. The compatibility of xenogeneic cell and the compatibility of xenogeneic tissue were good.

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    Targeting effect of hyaluronic acid coupled chitosan nanoparticles on non-small cell lung cancer
    Liang Heng-lun, Li Jing, Tong Jian, Zhang Fu-wei, Ruan Bao-qin
    2011, 15 (21):  3847-3850.  doi: 10.3969/j.issn.1673-8225.2011.21.011
    Abstract ( 168 )   PDF (1190KB) ( 682 )   Save

    BACKGROUND: CD44 has been found to be over-expressed in non-small cell lung cancer (NSCLC). Hyaluronic acid (HA) has a high affinity state with CD44 and has the potential as a targeted delivery vehicle for chemotherapy agents.
    OBJECTIVE: To evaluate the targeting effect of HA coupled chitosan nanoparticles (HACTNPs) on NSCLC.
    METHODS: HACTNPs bearing Docetaxel (DTX-HACTNPs) were prepared by ionotropic gelation. The nanoparticles were characterized for their shape by transmission/scanning electron microscopy. The particle size distribution was assessed by laser scattering. The biocompatibility of FITC-labeled nanoparticle formulations was evaluated for in vitro cytotoxicity by MTT assay using CD44+A549 cell lines.
    RESULTS AND CONCLUSION: The DTX-HACTNPs appeared to be spherical in shape and the mean size was found to be around (228.0±2.6) nm with low polydispersity index. The cytotoxicity of DTX-HACTNPs was higher than that of DTX-CTNPs, but lower than that of conventional DTX for injection. And their IC50 were (15.06±0.94), (25.73±3.37), (5.35±0.61) mg/L, respectively (F=73.871, P=0.000). The results indicate that HACTNPs are anticipated to be promising alternate carriers for targeting of CD44+ tumor cells.

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    Cytotoxicity effect of MePEG-PLA nanoparticles prepared by modified self-emulsion solvent diffusion technique on osteoblasts in vitro
    Wang Zhong-lei, Gao Yan, Lai Chun-hua, Lu Hai-bin, Li Shao-bing, Jiang Ying, Wei Cong-yun, Zhou Lei
    2011, 15 (21):  3851-3854.  doi: 10.3969/j.issn.1673-8225.2011.21.012
    Abstract ( 168 )   PDF (1127KB) ( 316 )   Save

    BACKGROUND: Amphiphilic block copolymers have been widely applied in the drug delivery system because of the high capacity of drug carriers, nanoparticles and long circulation time.
    OBJECTIVE: To evaluate the cytotoxicity effect of MePEG-PLA nanoparticles prepared by modified self-emulsion solvent diffusion technique on MG63 in vitro.
    METHODS: MePEG-PLA nanoparticles were prepared by modified self-emulsion solvent diffusion technique. The cytotoxicity effect of MePEG-PLA nanoparticles on MG63 was detected using MTS assay at days 1, 2, 3. Particles size, polydispersity index and Zeta electric potential were measured by laser particle size analzer. The morphology of MePEG-PLA nanoparticles were observed by transmission electron microscope. Absorbance values at days 1, 2, 3 were detected by microplate reader.
    RESULTS AND CONCLUSION: MePEG-PLA nanoparticles had a regular spherical shape with the mean diameter of 25.7 nm and scattered evenly. The Zeta potential was -8.06 mV. The cytotoxicity grade of MePEG-PLA nanoparticles was 0. The results indicate that MePEG-PLA nanoparticles prepared easily by modified self-emulsion solvent diffusion technique are nontoxic to the MG63 and have a good prospect.

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    Cross-linked alginate/heparin coated cardiopulmonary bypass support device
    Liu Dong, Li Tong, Yu Mei-li, Hu Xiao-min, Duan Da-wei, Li Xin
    2011, 15 (21):  3855-3858.  doi: 10.3969/j.issn.1673-8225.2011.21.013
    Abstract ( 132 )   PDF (578KB) ( 472 )   Save

    BACKGROUND: Currently, non-heparin-coated pipe and tube have a great impact on internal cardiopulmonary bypass (CPB) cardiac surgery, which can cause blood damage, heavy inflammatory response, and influence the postoperative recovery and survival of patients.
    OBJECTIVE: To develop a new heparin-coated CPB pipe by using the bomedical polymer materials, and to study its stability and performance of anticoagulant.   
    METHODS: CaCl2 was used to form Ca2+ membrane for modifying the inner surface of medical polyvinyl chloride (PVC) pipe cross-linking with sodium alginate and heparin. The Ca2+ reacted with Na+ which was in the sodium alginate and heparin, so that the linear polymer cross-linking molecules were to form chemical cross-linked sodium alginate-heparin complex network structure, a type of biomaterial heparin coating.
    RESULTS AND CONCLUSION: CaCl2 modified activated medical PVC cardiopulmonary bypass pipe reacting with heparin and sodium alginate to bring out the cross-linking reaction and form biological polymers heparin-coating pipe. The heparin-coated pipe has been proved that it has good blood compatibility, stability, anti-coagulation performance to meet short-term extracorporeal circulation bypass.

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    Particle size and morphology characterization of polystyrene microspheres prepared by dispersion polymerization
    Liang Bo, Wu Lan-er, Zhang Xue
    2011, 15 (21):  3859-3862.  doi: 10.3969/j.issn.1673-8225.2011.21.014
    Abstract ( 164 )   PDF (674KB) ( 550 )   Save

    BACKGROUND: According to market needs, production of polystyrene microspheres with appropriate particle size is an important daily work of process technique control. Microspheres fabricated by dispersion polymerization have good mono-dispersion, the particle size can be synthesized from several hundred nanometers to a few microns.
    OBJECTIVE: To investigate the influence of dispersing medium and monomer dosage of dispersion polymerization on the particle size the distribution width of the polystyrene microspheres.
    METHODS: In the three-necked bottle with mechanical agitation and condensation tube import and export holes, a certain amount of polyvinylpyrrolidone, ethanol and water were added for pre-dispersion at 70 ℃ for 30 minutes, a monomer styrene dissolving azobisisobutyronitrile was slowly dropped, followed by a polymerization reaction at 70 ℃ for 8 hours, then centrifugation, washing and drying, thus monodisperse polymer microspheres were prepared. By scanning electron microscopy, the morphology of polystyrene microspheres was characterized, the particle size of polystyrene microspheres was measured by laser particle size analyzer.
    RESULTS AND CONCLUSION: Using ethanol/water as the dispersing medium and certain amount of the monomer, the particle size of polystyrene microspheres prepared by dispersion polymerization was at a range of 1-2 μm, and the distribution width was 0.715-0.965.

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    Nano silver-porcine small intestine submucosa and polypropylene mesh for repair of rabbit abdominal injury: A comparative study
    Zhang Chun-yang, Xu Ya-na, Wei Xin-lin, Zhou Zhong-xiao, Zhang Jian
    2011, 15 (21):  3863-3866.  doi: 10.3969/j.issn.1673-8225.2011.21.015
    Abstract ( 129 )   PDF (695KB) ( 329 )   Save

    BACKGROUND: It is essential to find the ideal replacement materials for abdominal injury.
    OBJECTIVE: To compare the application effect of composite repair materials-nano silver-porcine small intestine submucosa and polypropylene mesh on abdominal injury in rabbits..
    METHODS: Composite repair materials-nano silver-porcine small intestine submucosa, experimental models (3×3 cm) with abdominal injury in rabbits caused by operation were prepared. Twenty white rabbits were randomly divided into experimental and control groups. Composite materials were used to repair abdominal injury in experimental group; polypropylene mesh was used to repair abdominal injury in control group. Postoperative recovery of rabbits was observed and the cytotoxicity of composite materials was evaluated after operation. Rabbits underwent tensile strength of abdominal wall determination, intra-abdominal adhesion score, and histological observation at 1, 2 and 4 months after repair.
    RESULTS AND CONCLUSLON: Two groups were simultaneously compared after operation, the extent and intensity of abdominal adhesions in composite materials were significantly lower than that in polypropylene mesh at the same time point (P < 0.05). The extent and intensity of abdominal adhesions in the two groups were higher at 4 months after repair than at 1 month after repair (P < 0.05). The tensile strength of composite materials was higher than that of polypropylene mesh at 1 and 2 months after repair (P < 0.05); and up to the fourth month, the tensile strength was similar in the two groups (P < 0.05). These two repair materials have good repair capacity, which can maintain adequate tensile strength of abdominal wall after operation. However, composite materials in terms of histocompatibility and anti-abdominal adhesion are superior to polypropylene mesh. The self-made nano silver-porcine small intestine submucosa feeding has no cytotoxicity, and which has feasibility of repairing abdominal injury as tissue engineering material.

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    Histological and biomechanical evaluation in the interface between nano-surface titanium alloy implants and bone
    Huang Cheng-long, Zhao Chang-li, Han Pei, Ji Wei-ping, Guo Shang-chun, Jiang Yao, Zhang Xiao-nong
    2011, 15 (21):  3867-3870.  doi: 10.3969/j.issn.1673-8225.2011.21.016
    Abstract ( 147 )   PDF (586KB) ( 358 )   Save

    BACKGROUND: Prosthetic looseness is the main cause of arthroplasty failure and revision. Surface treatment of the materials can promote the osseointegration rate and the stability of implants.
    OBJECTIVE: To evaluate the osseointergration of nano-surface titanium alloy (Ti6A14V) implant in animals.
    METHODS: Novel nanophase Ti6A14V substrates were prepared according to the severe plastic deformation principle. Ti6A14V substrate implants with common surface, hydroxyapatite-coated surface and nanophase surface were transplanted into each femoral intercondylar notch of beagle dogs. Three months later, all the beagle dogs were checked with X-ray film, then sacrificed. The condyles of femur with the implants were taken out, non-decalcification group sections were prepared for Van Gieson staining, bone ingrowth between the interfaces of the bone-implant were studied and kinesics parameter was measured. Pull-out test was applied to compare the shear strength between the interfaces of the bone-implant.
    RESULTS AND CONCLUSION: Radiographic examinations showed bone recovery around the implant and no obvious lucent gap in the interface of implant-bone. Histological examination suggested that lots of mature trabecular bone formed around Ti6A14V substrate implants with hydroxyapatite-coated surface and nanophase surface, the interface osseointegration rates showed no difference between them (P > 0.05), but all significantly higher than that of Ti6A14V substrate implants with common surface (P < 0.001). Pull-out test demonstrated that shear strength showed no difference between Ti6A14V substrate implants with hydroxyapatite-coated surface and nanophase surface (P > 0.05), but all significantly stronger than that of Ti6A14V substrate implants with common surface (P < 0.001). Ti6A14V substrate implants with nanophase surface improves the bone-implant osseointegration in vivo as hydroxyapatite-coated surface did, suggesting that novel nanophase Ti6A14V substrates prepared according to the severe plastic deformation principle may has a bone induction activity and might has a prosperous future for implant applications.

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    Treatment of osteomyelitis in rabbits with plastic nanohydroxyapatite/poly (3-hydroxybutyrate-hydroxyvalerate)-polyethylene glycol drug delivery system
    Zhang Bo-ping, Tang Shan-hua, Zhang Li, Lü Ren-fa, Lu Hai-feng, Jin An-min, Wang Xu-dong
    2011, 15 (21):  3871-3876.  doi: 10.3969/j.issn.1673-8225.2011.21.017
    Abstract ( 106 )   PDF (793KB) ( 344 )   Save

    BACKGROUND: Existing local drug delivery system is mostly massive, cannot arbitrary moulding and is difficult to completely sticking with the bone cavity, which easily lead to recurrence of osteomyelitis, and obvious effect of drug burst release, small amount of drug loading, short releasing time, and certain antigenicity. Therefore, a new type of plastic local drug delivery system was developed by task force and South China University of Technology, in order to provide a better method of treatment of osteomyelitis.
    OBJECTIVE: To investigate the therapeutic effect of the plastic nanohydroxyapatite/poly (3-hydroxybutyrate-hydroxyvalerate)-polyethylene glycol-gentamicin local drug delivery system (nano-HA/PHBV-PEG-GM-DDS) on osteomyelitis.
    METHODS: Proximal tibia osteomyelitis model of rabbits was prepared. Staphylococcus aureus was injected into proximal tibia bone window after 2 weeks and underwent debridement. The plastic nano-HA/PHBV-PEG-GM-DDS of 1 mL was implanted into groupⅠ, the plastic nano- HA/PHBV-PEG of 1 mL mixed gentamicin power of 23.2 mg into group Ⅱ, the plastic nano- HA/PHBV-PEG of 1 mL in conjunction with intramuscle gentamicin into group Ⅲ 5 days, a total of 23.2 mg, the plastic nano-HA/PHBV-PEG of 1 mL without antibiotic in group Ⅳ, and nothing into group Ⅴ. Specimens were harvestd 8 weeks after the above procedures and then were subjected to radiological, histological and bacteriological examinations.
    RESULTS AND CONCLUSION: In groupⅠ, the bacteria counting and X-ray Norden scoring were by far the smallest among all 5 groups (P < 0.01)，with no histological manifestation of osteomyelitis. In groupⅡ, Ⅲ, and Ⅳ, the bacteria counting gradually increased and there was significant difference among three groups (P < 0.01). However, there was no significant difference in improved X-ray Norden scoring among 3 groups (P > 0.05); histological manifestation had also no essential difference. The bacteria counting and Norden scoring as well as the histological manifestation in groupⅡ, Ⅲ, and Ⅳ were significantly higher than those in group Ⅴ (P < 0.01 or 0.05), its histology showed severe osteomyelitis manifestation. The results showed that the plastic nano- HA/PHBV-PEG-GM-DDS could be implanted as primary graft into the remaining infected defect after debridement to effectively treat osteomyelitis. Conventional systemic antibiotic or simple local antibiotic following debridement was not effective in treating chronic osteomyelitis. Primary bone grafting would rather make the condition worse, under without any antibiotic or conventional systemic antibiotic or simple local antibiotic.

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    Surface preparation of dental implant and osseointegration: Clinical application of 3i implant system
    Xiao Fei, Liu Yi, Wang Shuo-lin, Xu Hao, Guo Li-qiang, Zhao Bao-dong
    2011, 15 (21):  3877-3881.  doi: 10.3969/j.issn.1673-8225.2011.21.018
    Abstract ( 187 )   PDF (554KB) ( 504 )   Save

    BACKGROUND: Implant denture has been the conventional restoration means of dentition defect and edentulous gradually. A variety of implant systems are applied domestically and abroad with respective clinical effects.
    OBJECTIVE: To investigate the clinical effects of 3i implant system with double-etched surface preparation.
    METHODS: Ninety-five patients were selected as subjects. A total of 157 3i implants were implanted after contraindications to dental implantation were excluded. In view of various conditions of the soft and hard tissues in edentulous area, different surgical techniques were adopted accordingly. Permanent restorations were finished 1 to 3 months after the implantation. The following period was 24 months. Clinical effects were evaluated through clinical and imaging examination.
    RESULTS AND CONCLUSION: Favorable osseointegration was formed rapidly and no X-ray radiolucent area around the implants was observed in 157 implants. There was no implant loosening or shedding. High degree of satisfaction from patients was achieved. Both the survival rate and successful rate of implants were 100%. Implants with double-etched surface preparation facilitate the osteoblasts chemotaxis and osseointegration. 3i implants system could be considered as a manageable and effective implant system with shorter treatment course.

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    Rigidfix and Endobutton femoral fixation device, Intrafix tibial fixtaion device in arthroscopic reconstruction of anterior cruciate ligament using autografts of hamstring tendon
    Feng Wei, Xu Jian-zhong, Xin Ruo-bing, Wu Zeng-pu
    2011, 15 (21):  3882-3886.  doi: 10.3969/j.issn.1673-8225.2011.21.019
    Abstract ( 221 )   PDF (644KB) ( 734 )   Save

    BACKGROUND: Arthroscopic reconstruction of anterior cruciate ligament (ACL) is the golden standard for injured anterior cruciate ligament. However, it remains controversial in tendon fixation pattern.
    OBJECTIVE: To evaluate clinical effects of arthroscopic ACL reconstruction by using hamstring autograft with femoral fixation via Rigidfix, Endobutton system and tibial fixation via Intrafix system.
    METHODS: Thirty cases of patients were chosen from Department of Joint Surgery, First Affiliated Hospital of Zhengzhou University (2009-05 to 2010-05), which had been treated with arthroscopic ACL reconstruction by using hamstring autograft with femoral fixation via Endobutton, Rigidfix system and tibial fixation via Intrafix system. They all had been identified as ACL injure or ligament ruptures in arthroscopy. They were in a age range of 16 to 45, and twenty-two males with eight females. The femoral fixation was via Endobutton, Rigidfix system and tibial fixation via Intrafix system. The short-term effectiveness was observed postoperatively and knee function was evaluated by Lysholm and IKDC systems.
    RESULTS AND CONCLUSION: All 30 patients were followed up for 5-17 months (12 months on average), during when there were no severe complications and all injured knee-joints were with a normal mobility. Lysholm and IKDC systems showed that the scores ascended respectively from (50.0±6.0) before surgery to (85.5±3.5) and (49.5±5.5) to (87.0±2.5) (P < 0.05). These all indicates that this method of Rigidfix and Endobutton femoral fixation device, Intrafix tibial fixtaion device in arthroscopic reconstruction of ACL using autografts of hamstring tendon owns many advantages such as good short-term effectiveness, reliable graft fixation and less complications, which gets a good clinical recovery effectiveness.

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    Preparation and properties of chitosan/poly(ε-caprolactone) blend films
    Min Xiang, Tang Min-jian, Jiao Yan-peng, Zhou Chang-ren
    2011, 15 (21):  3887-3890.  doi: 10.3969/j.issn.1673-8225.2011.21.020
    Abstract ( 193 )   PDF (920KB) ( 383 )   Save

    BACKGROUND: Chitosan/poly(ε-caprolactone) (Chitosan/PCL) blend has a perspective in biomaterials. However, it is still unknown that the correlation between protein adsorption and cell activity on blends.
    OBJECTIVE: To investigation the correlation between protein adsorption behaviors and cell activities on chitosan/PCL blend films
    METHODS: Chitosan/PCL films with different mass ratios were prepared by spin coating with chitosan/PCL mixture solution. Atomic force microscopy (AFM), drop shape analyzer (DSA), quartz crystal microbalance (QCM) and MTT method were used to analyze the surface morphology, hydrophilicity, protein adsorption and cell metabolic activity of films.
    RESULTS AND CONCLUSION: The topography, hydrophilicity, protein adsorption and cell metabolic activity of films are largely related to the mass ratio of chitosan and PCL. The cell metabolic activity observed on hydrophobic PCL films is superior and cell adhesion level on hydrophilic chitosan films is excellent.

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    Effects of fusidic sodium combining rifampicin on Staphylococcus epidermidis biofilm in vitro
    Huang Liang-ku, Xu Tao, Tang Jin, Peng Li-hua, Chen Shi-rong
    2011, 15 (21):  3891-3894. 
    Abstract ( 146 )   PDF (1340KB) ( 395 )   Save

    BACKGROUND: Staphylococcus epidermidis is the major pathogen for the infection of the material after implantation, the underlying pathogenic mechanism is to form biofilm in the material surface, single drug administration is less effective to inhibit the growth of bacteria following biofilm formation.
    OBJECTIVE: To investigate the effect of fusidic sodium combining rifampicin on Staphylococcus epidermidis biofilm in vitro.
    METHODS: The biofilm was cultured in vitro. Tube dilution method was used to measure the minimal inhibitory concentration of fusidic sodium and rifampicin. The biofilm at early stage and mature stage was treated by fusidic sodium, rifampicin and the combination of fusidic sodium with rifampicin, which lower than the minimal inhibitory concentration. The influence of the combined administration on biofilm at early and mature stages was investigated.
    RESULTS AND CONCLUSION: Fusidic sodium and rifampicin can inhibit Staphylococcus epidermidis adhesion and biofilm formation, and have bactericidal effects on the early and mature biofilm bacteria, the combination is much better than alone (P < 0.05). The joint use of fusidic sodium and rifampicin can remarkably inhibit Staphylococcus epidermidis adhesion and biofilm formation, destroy the early and mature Staphylococcus epidermidis-biofilm and has significant bactericidal activity, it is a good choice for treatment of bacterial biofilm related infections.

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    Connective tissue changes at the position of tendon injury following implantation of streptomycin combined with slow-releasing biodegradable membrane
    Fu Ling, Song Ning, Su Xue-zhong, Li Na-ran, Sun Pei-jie, Su Qiu-xiang, Yang Xiao-xia
    2011, 15 (21):  3895-3899.  doi: 10.3969/j.issn.1673-8225.2011.21.022
    Abstract ( 134 )   PDF (1589KB) ( 319 )   Save

    BACKGROUND: Domestic and foreign scholars have used biological, non-biological, drug and other methods, such as biofilm, sodium hyaluronate, cellulose sealant, to perform a large number of studies on anti-adhesion tendon repair. However, there is no breakthrough up to now.
    OBJECTIVE: To observe the proliferation of connective tissues after implantation of streptomycin combined with slow-releasing biodegradable membrane.
    METHODS: After tendon cutting, SD rats were randomly divided into three groups: In group A, streptomycin combined with slow-releasing biodegradable membrane was implanted into the sutured site of Achilles tendon; in group B, vitamin C combined with slow-releasing degradable membrane were implanted; in group C, single slow-releasing degradable membrane was used. After 90 days, histological observation was performed for tendon injury as well as tractus hydroxyproline content and biomechanics indexes were measured.
    RESULTS AND CONCLUSION: In the group A, there were more fibroblasts and collagen fibers in the sutured site of Achilles tendon than its surrounding tissues, group B and group C. Surrounding the sutured site, many loose connective tissue with normal structure could be seen, but few hyperplastic connective tissues grew into the tendon. A clear demarcation existed between the tendon and its peripheral tissues. The content of hydroxyproline and the ultimate tensile strength in group A were higher than those of groups B and C. The findings show that streptomycin combined with slow-releasing biodegradable membrane can alleviate or prevent tendon adhesion through inhibiting peripheral connective tissue proliferation and preventing connective tissue to grow into the tendon.

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    Epidermal growth factor combined with degradable collagen membrance in prevention of tendon adhesion
    Wang Ji-hong, Wen Shu-zheng
    2011, 15 (21):  3900-3904.  doi: 10.3969/j.issn.1673-8225.2011.21.023
    Abstract ( 210 )   PDF (563KB) ( 360 )   Save

    BACKGROUND: The problems such as fast drug degradation, great drug loss and poor barrier effect exist when using liquid molecular biomaterial as barriers in preventing tendon adhesion. Accordingly, it has aroused increasing attention to seek for membrane biomaterials as barriers. Simultaneously, it found that tendon cells would proliferate and differentiate under controls of multiple endogenous growth factors that promote tendon endogenous healing. However, it is poorly understood which the specificity factor for tendon healing is. 
    OBJECTIVE: To study effect of epidermal growth factor (EGF) combined with degradable collagen membrane on preventing tendon adhesion and improving tendon endogenous healing.
    METHODS: Thirty ten-month old leghorn cocks were randomly divided into 3 groups, with 10 animals in each group. The third toe of left foot of each animal was prepared for avulsion model, and sutured with improved Kessler method. The broken ends were encapsulated with EGF combined with degradable collagen membrane (combination group), degradable membrane alone (collagen membrane group) or without treatment (blank control group). Four weeks later, the specimens were evaluated by gross observation, biomechanical test, light microscope and electron microscope.
    RESULTS AND CONCLUSION: In the combination group, there were a large amount of type Ⅰ collagen inside the sutured tendon, they were closely and lined up in order. The amount of collagen-fibronectin was less and the adhesion obviously was less than the control group. The tendon cells were matured. The adhesion in the collagen membrane group was slightly, there were a large amount of type Ⅲ collagen inside the sutured tendon, which loosely but well organized. In the blank control group, type Ⅰ and Ⅲ collagen arranged crisscrossed, with heavy adhesion. The results suggest that EGF can promote tendon endogenous healing and degradable collagen membrane can prevent tendon exogenous healing, thus, prevent the formation of adhesion.

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    Effects of bone wax and oxidized regenerated cellulose on the hemostasis of the sternum in elderly women undergoing open heart surgery
    Wang Chun, Dong Si-yuan, Gu Tian-xiang, Fang Qin, Song Lai-chun, Yu Lei
    2011, 15 (21):  3905-3908.  doi: 10.3969/j.issn.1673-8225.2011.21.024
    Abstract ( 98 )   PDF (720KB) ( 617 )   Save

    BACKGROUND: Oxidized regenerated cellulose has been used in neurological surgery and otolaryngology, but there is no report about oxidized regenerated cellulose applied in heart surgery for sternal bleeding.
    OBJECTIVE: To compare the effects of oxidized regenerated cellulose and bone wax on sternal bleeding and infections during open heart surgery in old women.
    METHODS: Totally 68 female patients over 60 years undergoing open heart surgery were divided into oxidized regenerated cellulose group and bone wax group. The sternal wound and bone marrow cavity of the former group was filled with oxidized regenerated cellulose and bone wax group with medical bone wax. Recording operating time, cardiopulmonary bypass time, time of closing chest, total drainage volume, re-exploration for bleeding, the volume of blood transfusion, suture removal time, average hospital stay, postoperative sternal wound healing were recorded.
    RESULTS AND CONCLUSION: The comparison between two groups in operating time, time of closing chest, total drainage volume, re-exploration for bleeding, the volume of blood transfusion was significantly different (P < 0.05). These indexes were improved dramatically in the oxidized regenerated cellulose group. The mortality, suture removal time, average hospital stay and postoperative sternal wound healing were no significantly different between two groups. Oxidized regenerated cellulose as a new material for sternal hemostasis can be routinely used after cardiopulmonary bypass, and the early results of the study showed its effectiveness and safety.

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    Effects of hemoperfusion using HA130 resin hemoperfusion apparatus on microinflammatory state in maintenance hemodialysis patients
    Zhou Xi-yu, Song Jie, Zhang Xiao-dong, Li Ying, Li Hui
    2011, 15 (21):  3909-3912.  doi: 10.3969/j.issn.1673-8225.2011.21.025
    Abstract ( 129 )   PDF (626KB) ( 527 )   Save

    BACKGROUND: Studies have found that the microinflammatory state exists in uremic patients undergoing maintenance hemodialysis (MHD).
    OBJECTIVE: To investigate the effects of hemoperfusion using HA130 resin hemoperfusion apparatus on microinflammatory state in MHD patients.
    METHODS: Sixty uremia patients undergoing maintenance hemodialysis were divided into two groups: hemoperfusion group (n=30) and MHD group (n=30). Hemoperfusion group underwent the treatment of hemoperfusion using HA130 resin hemoperfusion apparatus combined with hemodialysis. MHD group underwent the treatment of hemodialysis. The serum levels of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL–6) and tumor necrosis factor alpha (TNF-α) of all patients in the two group were detected before and after the treatment.
    RESULTS AND CONCLUSION: In the hemoperfusion group, the serum levels of hs-CRP, IL-6 and TNF-α were lower after treatment than those before treatment, and the difference was significant (P < 0.05); In the MHD group, the serum levels of hs-CRP, IL-6 and TNF-α were higher after treatment than those before treatment, and the difference was not significant (P > 0.05). The results indicate that hemoperfusion using HA130 resin hemoperfusion apparatus can reduce the serum levels of hs-CRP, IL-6 and TNF-α and control the microinflammatory state in MHD patients.

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    Polymer polyethylene membrane plasma separator in hyperlipemia: A 35-case analysis
    Yu Ying, Meng Jian-zhong, Jing Ying, Wang Su-xia, Ge Yan-ming, Jia Feng-yu
    2011, 15 (21):  3913-3916.  doi: 10.3969/j.issn.1673-8225.2011.21.026
    Abstract ( 112 )   PDF (500KB) ( 295 )   Save

    BACKGROUND: Blood lipid cleaning (BLC) can effectively reduce 50-70% of the level of cholesterol (CH), glycerin trilaurate (TG), low density lipoprotein (LDL), lipoprotein (a) and fibrinogen by double filtration plasmapheresis, without affecting the other components of plasma such as albumin, globulin, immune proteins, and electrolytes.
    OBJECTIVE: To observe the effect of polyethylene membrane plasma separator and membrane plasma separator in the treatment of hyperlipidemia.
    METHODS: A total of 35 cases of patiants with hyperlipemia were treated by BLC with polyethylene membrane plasma separator and membrane plasma separator. The operation of BLC machine, the use of anticoagulant dosage, blood, and immune outcome measures were performed according to operation procedure and corresponding monitoring data.
    RESULTS AND CONCLUSION: The level of blood-fat was significantly reduced and the blood viscidity was lowered in 35 cases after treatment. The clinical symptoms such as drowsiness, insomnia, unfocused were visibly improved. Existing diabetes, hypertension and coronary disease were more easily controlled, including 5 cases of coronary heart disease was often accompanied by episodes of chest pain and chest tightness, and free of recurrence by BLC. Glucose was controlled preferably in 9 cases of diabetes after the treatment of BLC. It is indicated that the clinical effect of BLC with polyethylene membrane plasma separator and membrane plasma separator in the treatment of hyperlipemia was reliable, large sample test needs to be further verified.

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    Tendon allograft materials for repair of posterior cruciate ligament injury combined with posterolateral complex injury
    Huang Ke-jian, Sun Hui, Gao Li-hua, Zang Xue-hui
    2011, 15 (21):  3917-3920.  doi: 10.3969/j.issn.1673-8225.2011.21.027
    Abstract ( 130 )   PDF (493KB) ( 404 )   Save

    BACKGROUND: Selection of tendon allograft materials for posterior cruciate ligament (PCL) injury combined with posterolateral complex (PLC) injury is controversial.
    OBJECTIVE: To observe the effect of tendon allograft materials on PCL plus PLC injuries during reconstruction.
    METHODS: Fifteen patients with arthroscopic PCL plus PLC injuries of the knee joint received knee joint construction with tendon allograft supported by Shanxi Provincial Medical Tissue Bank. Original remnants of the PCL were retained as much as possible. PCL tibial and femoral tunnel were prepared, and extrusion screws were introduced during allogeneic tendon repair.
    RESULTS AND CONCLUSION: Degree of knee joint flexion and extension was improved greatly after reconstruction (P < 0.01). The drawer test results showed that there were 4 cases of 2+ and 11 of 4+ before reconstruction as well as 8 negative cases, 6 of 1+ and 1 of 2+ after reconstruction. After reconstruction, the varus stress test was negative at 30° of flexion and full extension, indicating that the retrusion degree and stability of the joint was significantly improved. Lysholm scores had a great increased as compared with before reconstruction (P < 0.01). No knee joint rejection, infection and other complications were found during the follow-up period. The results confirmed that the tendon allograft reconstruction of PCL plus PLC injuries cannot damage the normal structure with satisfactory effects.

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    Methods and efficacy of surface bioactivity modification for titanium and titanium alloy
    Yan Jie, Cao Cong, Dong Yu-qi
    2011, 15 (21):  3921-3924.  doi: 10.3969/j.issn.1673-8225.2011.21.028
    Abstract ( 156 )   PDF (571KB) ( 520 )   Save

    BACKGROUND: Titanium and titanium alloy are commonly used for medical biological materials, they have good biocompatibility, but lack of the ability of bone induction, the contact between titanium and bone tissue is a mechanical contact.
    OBJECTIVE: To review the methods and efficacy of surface bioactivity modification for titanium and titanium alloy, and to provide references for further clinical application.
    METHODS: A computer-based online search of literatures related to methods of surface bioactivity modification for titanium and titanium alloy was performed in PubMed database and CNKI database using the key words of “titanium, titanium alloy, coating, bioactivity, bone” in English and in Chinese respectively.
    RESULTS AND CONCLUSION: The surface modification methods include plasma spraying, micro-arc oxidation, sol-gel and biomimetic methods. The surface coating of titanium and titanium alloy has been developed from a single coating to the composite coatings, gradient coatings and nano-gradient coatings. The joint use of two or three modification methods enhances the properties of the coating. After the surface modifications, the efficacy is investigated by simulating body fluid soaking, the culture of the osteoblasts, bone affinity fluorescein staining and radiology detection. Surface bioactivity modification for titanium and titanium alloy is a complex engineering, which requires to consider the bioactivity of surface coating and its bonding strength between the substrate, as well as the ability of bone induction. With the development of surface modification technology, the bioactivity and binding of surface coating for titanium and titanium alloy will be enhanced.

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    Application of fluorid in orthodontic enamel adhesive
    Zhang Xiao-hui, Liu Mei-tian, Feng Zhi-yuan, Ran Hai-qun, Liu Bin
    2011, 15 (21):  3925-3928.  doi: 10.3969/j.issn.1673-8225.2011.21.029
    Abstract ( 151 )   PDF (690KB) ( 431 )   Save

    BACKGROUND: Demineralization of dental enamel is a complication in common after orthdontics treatment. The application of fluoride can inhibit the occurrence of demineralization of dental enamel and promote enamal remineralization.
    OBJECTIVE: To explore the mechanism and the application of fluoride in enamel adhesive in preventing enamel demineralization and reducing incidence of the enamel blazes after the treatment.
    METHODS: PubMed database from January 1990 to August 2010 was retrieved by computer with the key words of “fluoride release; enamel demineralization; enamel adhesive; orthdontics treatment” in English. CNKI database from January 1990 to August 2010 was retrieved with the key words of “fluoride release; enamel demineralization; enamel adhesive; orthdontics treatment” in Chinese. Literatures were limited to English and Chinese. Literatures concerning the development and clinical application of fluoride in enamel adhesive were included.
    RESULTS AND CONCLUSION: Hydroxy of Hhydroxyapatite unit cell was displaced by fluorine, the crystallinity, stability and hardness of apatite unit cell were enhanced. Fluorinion, calcium and phosphate ions in saliva constitute a mineralization system to improve the effect of enamal remineralization. The development of resin adhesive with slow-release fluorine source is an important direction to prevent demineralization of dental enamel. The effect of fluorine releasing in resin adhesive with inorganic and organic slow-release fluorine has been verified, and its clinical effect is need to be further studied.

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    Reparation of segmental defects by vascular endothelial growth factor combined with bone substitutes
    Lü Jun, Wang Pei-ji
    2011, 15 (21):  3929-3933.  doi: 10.3969/j.issn.1673-8225.2011.21.030
    Abstract ( 126 )   PDF (613KB) ( 484 )   Save

    BACKGROUND: The therapy for limb defects caused by injury, infection, tumor excision and congenital diseases is one of the commonest and most thorny problems in orthopedic clinics.
    OBJECTIVE: To summarize the biological characteristics of vascular endothelial growth factor (VEGF), the mechanism of composite artificial bone and the application of regional gene therapy in bone defects.
    METHODS: A computer-based online search of CNKI database and Pubmed database from January 1999 to December 2009 was performed for relative articles about VEGF and bone defect repair, with key words of “VEGF, Bone defect, Bone substitute, Gene therapy” in English and in Chinese by screening titles and abstracts. The documents that associated with VEGF and bone defect repair were selected, and those published recently or in authoritative journals were preferred in the same field.
    RESULTS AND CONCLUSION: Totally 285 articles were obtained in initial retrieval, 45 articles of them were chosen to summarize based on inclusion criteria. VEGF is a special growth factor promoting vascular permeability and angiogenesis, and it plays close coordination role between angiogenesis and osteogenesis in the growth, development and reconstruction of bone. Present artificial bone materials only have characteristics of conducting osteogenesis. Thus improving the angiogenesis of artificial bone materials can promote the formation of bone tissue with abundant blood supply.

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    Biomaterials of cruciate ligament reconstruction of exercise-induced knee injuries: Analysis of selection and the advantages and disadvantages
    Ren Gang
    2011, 15 (21):  3934-3936.  doi: 10.3969/j.issn.1673-8225.2011.21.031
    Abstract ( 80 )   PDF (495KB) ( 346 )   Save

    OBJECTIVE: To analyze the advantages and disadvantages of cruciate ligament reconstruction after exercise-induced knee injuries using various biomaterials, to provide theoretical basis for clinical application and selection of biomaterials for cruciate ligament reconstruction of exercise-induced knee injury.
    METHODS: Articles addressing synthetic knee joint ligament were retrieved from VIP database with the key words of cruciate ligament of knee, exercise, ligament repair, ligament reconstruction, artificial synthetic material in Chinese between January 1987 and September 2010. Highly related articles and strongly pertinent articles were included, outdated and duplicated researches were excluded. Totally 16 literature were involved in final analysis.
    RESULTS: The repair materials for the reconstruction of cruciate ligaments of the knee joint mainly include autograft, allograft and artificial ligament. These three materials have its advantages and disadvantages, and show their own scope in clinical application.
    CONCLUSION: The cruciate ligament reconstruction of exercise-induced knee injuries is deemed to select the best material based on the individuality, age, injury mechanism and requirements after operation.

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    Suture technology and materials for tissue engineered cartilage
    Ma Zhi-xiang
    2011, 15 (21):  3937-3940.  doi: 10.3969/j.issn.1673-8225.2011.21.032
    Abstract ( 80 )   PDF (604KB) ( 324 )   Save

    BACKGROUND: The physical characteristics and functional structure of cartilage tissue suppress its self-rehabilitation after injury. The injured area of cartilage tissue can be sutured according to injury characteristics. Therefore, the choice of suture materials is particularly important. The development and application of degradable suture materials provides a greater protection to the application of suture technology.
    OBJECTIVE: To review the physiological characteristics of cartilage tissue and progress and application of surgical suture materials, to introduce the material characteristics and clinical application of degradable suture materials, and to guide the rational selection of suture materials and development of new materials.
    METHODS: A computer-based search of CNKI and PubMed databases was performed for relevant articles published from 1993-01 to 2011-01 using the keywords of “cartilage; seam; materials” in Chinese and English. Articles published in recent years or in authorized journals were preferred. Finally, 30 of 193 articles were included in result analysis.
    RESULTS AND CONCLUSION: The physiological characteristics of the cartilage restrict the self-repair effect, so resection surgery is often used. However, the postoperative effects are not ideal. Generally considered, cartilage tissues should be retained as far as possible. Meanwhile, it is found that the surrounding area of cartilage tissues has some self-repair ability. Therefore, to suture regular laceration can obtain a good effect. Degradable suture thread superior to non-degradable one cannot lead to secondary injury and provide a great potential and security for suture rehabilitation of cartilage tissue and suture technology development. With the advances in suture technology and development of new materials, cartilage suture repair as tissue engineering method can be used and improved gradually.

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    Tissue engineered ligament in repair of sports-induced anterior cruciate ligament injury
    Xu Rong-mei
    2011, 15 (21):  3941-3944.  doi: 10.3969/j.issn.1673-8225.2011.21.033
    Abstract ( 86 )   PDF (557KB) ( 380 )   Save

    BACKGROUND: Cruciate ligaments are the core of the knee joint, which can guide physical activity and limit non-physiological functions of the joint. The anterior cruciate ligament is especially important, and anterior cruciate ligament injury has become the hotspot in sports medicine.
    OBJECTIVE: To investigate the achievements on the physiological functions, injury mechanism and tissue-engineered materials used in the repair of anterior cruciate ligament.
    MEHTODS: A computer-based search was conducted in PubMed and VIP databases for articles published from January 1990 to February 2011 related to tissue engineering progress in anterior cruciate ligament, biomechanical analysis of tendon scaffold, biomaterials for tendon tissue engineering and tissue engineering technology in tendon repair. The keywords were “anterior cruciate ligament, biological materials, damage, treatment” in Chinese and English. 102 articles were retrieved.
    REUSLTS AND CONCLUSION: Tissue engineering rehabilitation measures for anterior cruciate ligament injury have developed greatly. However, from the view of material selection, single graft materials with many deficiencies are not conductive to ligament rehabilitation. Composite materials can make up the deficiencies of single materials in biocompatibility, degradation rate, biomechanical properties, and lack of toughness. In addition, functional and structural processing of tissue engineering materials is necessary, which can provide a good environment for cell adherence, growth and differentiation. Meanwhile, advances in genetic technology and new materials can meet the need for rehabilitation of anterior cruciate ligament to a greater extent.

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    Biocompatibility of urethral stent made from different materials
    Zhao Hu
    2011, 15 (21):  3945-3948.  doi: 10.3969/j.issn.1673-8225.2011.21.034
    Abstract ( 150 )   PDF (678KB) ( 347 )   Save

    BACKGROUND: The repair and reconstruction of urinary system are performed with various biological materials, which has been the focus of the reconstruction of medical research.
    OBJECTIVE: To evaluate the clinical effect, complication and application of urethral stent made from different materials in the treatment of urinary system disease and the effect of different implantation on avoidance of complications.
    METHODS: Researches were related to urethral stent implantation from Wanfang database (1990-01/2010-12) by computer with the key words of “urethral stent material, biocompatibility”. Repetitive, common summarization or Meta-analysis were excluded, 19 literatures were screened for evaluation.
    RESULTS AND CONCLUSION: At present, urethral stent made from different materials including Ni-Ti memory alloy mesh stent, Ni-Ti memory alloy helical stent, titanium wire helical stent and silica gel stent. Although Ni-Ti memory alloy helical stent had good flexibility and compatibility, and its dissepiments had favorable permeability and indeed reliable drainage, stent prone to lodging or overlay, and should not be long placed. Ni-Ti memory alloy mesh stent was significantly better than helical stent. Ni-Ti memory alloy mesh stent had large enough diameter and bearing and had a recent significant curative effect. The clinical effect of titanium wire helical stent in treatment of lower urinary tract obstruction in elderly. This may be associated with special fovea centralis of stent and difficult to shift and slip in urethra. Silica gel supporter with multi-side holes is conductive to the success of urethroplasty, reduce trauma, and does not affect the results of operations. Urethral stent for the production has a lot of choices; the method of implantation is different. In practical operation, we should according to the actual situation of patients and take corresponding measures to achieve the most satisfactory results.

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    In vitro degradation and clinical application of lactide-glycolic acid copolymer as ureteral stent materials
    Yu Yin-hua
    2011, 15 (21):  3949-3952.  doi: 10.3969/j.issn.1673-8225.2011.21.035
    Abstract ( 138 )   PDF (627KB) ( 473 )   Save

    BACKGROUND: Complications exist after transplantation of different forms of ureteral stents. Therefore, how to choose the appropriate stent to treat urinary tract disease is the medical research focus.
    OBJECTIVE: To investigate the in vitro degradation rule and clinical application of lactide-glycolic acid copolymer used as ureteral stent materials.
    METHODS: The first author searched PubMed (http://www.ncbi.nlm.nih.gov/PubMed) and Wanfang databases (http://www.wanfangdata.com.cn) for relevant articles published from 1991-01 to 2009-12 with the keywords of “SR-PLGA; in-vitro degradation; degradalion rate” in English and Chinese. Old and repetitive articles were excluded, and finally 17 of 135 articles were included.
    RESULTS AND CONCLUSION: There are few reports about the in vivo biodegradable properties of biodegradable polymer ureteral stent materials. As a biodegradable polymer material, natural degradation and compatibility is the primary condition for clinical application. It is of significance to understand material degradation and compatibility in clinical application. Lactide-glycolic acid copolymer as biodegradable ureteral stent material has a good biocompatibility, and the degradation rate of this copolymer can be effectively regulated by adjusting the glycolide and lactide component ratio.

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    Clinical application and biocompatibility of ophthalmic implant materials
    Hu Li-qun
    2011, 15 (21):  3953-3956.  doi: 10.3969/j.issn.1673-8225.2011.21.036
    Abstract ( 99 )   PDF (659KB) ( 567 )   Save

    BACKGROUND: There are some achievements on ophthalmic implant materials, but several problems still exist.
    OBJECTIVE: To conclude the progress in biological characteristics and clinical application of ophthalmic implant materials.
    METHODS: PubMed and CNKI databases were searched by computer using the keywords of “artificial crystal material, artificial sclera, artificial cornea” in Chinese and English to retrieve articles related to ophthalmic materials. Articles published in recent years or in authorized journals were preferred. Totally 29 articles were included.
    RESULTS AND CONCLUSION: Ophthalmic implant materials have been widely used in clinic. The focus is to increase the stability and effectiveness of artificial materials and reduce complication occurrence due to some certain biocompatibility of implant materials. It is the normal defense phenomenon of the body reacting to implant materials as intraocular foreign bodies. The material compatibility should be considered to ensure the implantation efficacy and reduce complications, which is of great significance for quality of life in patients after implantation.

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    Covered stents for craniocervical vascular diseases
    Han Deng-feng, Kong Xiang-feng, Tuerxun•Shabier
    2011, 15 (21):  3957-3960.  doi: 10.3969/j.issn.1673-8225.2011.21.037
    Abstract ( 68 )   PDF (820KB) ( 331 )   Save

    BACKGROUND: Endovascular treatment has become the preferred choice for craniocervical vascular diseases, including detachable balloons, coils, liquid embolic agent, and covered stent. The covered stent has two advantages: a higher rate of complete occlusion and lower recanalization rate.
    OBJECTIVE: To introduce several kinds of covered stents in China and to investigate the curative effects of covered stents on craniocervical artery aneurysms and carotid cavernous fistula.
    METHODS: A computer based search of Wanfang database was performed for relevant articles published between 1998-01 and 2010-12 using the keywords of “covered stent, biocompatibility, aneurysms, carotid cavernous fistula”. Repetitive articles and Meta analysis were excluded.
    RESULT S AND CONCLUSION: Jostent stent produced by Abbott, USA, and Willis stent produced by Shanghai Mini-invasive Company are commonly used in clinical neurosurgery. Jostent stent has a good biocompatibility and expansibility, and its porous structure can reduce cell spreading, and prevent platelet aggregation and inflammatory cell migration so as to reduce the probability of secondary thrombosis and vascular stenosis. However, the disadvantages of Jostent stent are limitations used in intracranial arteries: the bending angles of the artery cannot be very sharp, and non-occlusive perforating arteries and branches cannot exist around the lesion. Willis stent that completely changes the traditional concept about endovascular treatment of intracranial aneurysms has certain flexibility in the entire stent system which contributes to the intracranial vascular system, in particular, the siphon segment of carotid artery. Because of its simple operation and satisfactory effects, Willis stent offers a new direction for endovascular therapy development.

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    Ligation ring, tissue adhesive and sclerotherapy for esophageal varices
    Zhao Dong-mei, An Hong-jun, Jia Shan-shan
    2011, 15 (21):  3961-3964.  doi: 10.3969/j.issn.1673-8225.2011.21.038
    Abstract ( 249 )   PDF (528KB) ( 753 )   Save

    BACKGROUND: Currently, the efficacy of endoscopic sclerotherapy, endoscopic ligation and tissue glue embolization on esophageal varices has been recognized, but the differences in the efficacy of various methods exist.
    OBJECTIVE: To elaborate the material characteristics and biocompatibility of ligation ring, tissue adhesive and sclerosant so as to investigate the therapeutic effects of endoscopic sclerotherapy, endoscopic ligation and tissue glue embolization on esophageal varices.
    METHODS: An electronic search of CNKI (1989/2009) and Medline (1989/2009) databases was conducted to retrieve articles about biocompatibility of igation ring, tissue adhesive and sclerosant and their effects on esophageal varices. The keywords were “esophageal varices, ligation ring, sclerosant, tissue adhesive, therapy” in Chinese and “cerebrovascular disease, stent, therapy” in English. Repetitive articles, animal experiments and Meta analysis were excluded. Totally 17 articles were included.
    RESULTS AND CONCLUSION: The efficacy of endoscopic ligation and sclerotherapy on the control of acute bleeding and prevention of early bleeding has been confirmed, which has become the god standard for esophageal varices bleeding. The common sclerostant includes 5% sodium cod liver oil, 1% ethyl alcohol sclerosis, 5% oleic acid and other amino acids. The current tissue adhesives belong to α-cyanide-acrylate glues, which can be solidified due to anion-induced polymerization reaction. Bleeding at the puncture site can be seen after needle injection during sclerotherapy. After tissue adhesive injection, acute bleeding can be controlled. The short-term effect of endoscopic treatment for esophageal varices bleeding is obvious, but the long-term effect still needs further studies.

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    Biological properties of orthoses made of different materials
    Lin Zhi-wei, Wang Ying-qiu, Zheng Qun-xiang
    2011, 15 (21):  3965-3968.  doi: 10.3969/j.issn.1673-8225.2011.21.039
    Abstract ( 134 )   PDF (643KB) ( 783 )   Save

    BACKGROUND: Orthoses are used to prevent and correct deformity through the force in order to treat bone, joint, muscle and nerve disorders and compensate the functions.
    OBJECTIVE: To introduce the classification, properties, and curative effects of orthoses made of different materials.
    METHODS: A computer-based search of CNKI and PubMed databases(1996-01/2010-12) were performed using the keywords of “orthosis, biological properties, congenital club food, infants” in Chinese and “orthosis，congenital club foot” in English. Articles related to orthosis and congenital club foot were included, and repetitive article or Meta analysis were excluded. Finally, 20 articles were included in the result analysis. A retrospective analysis was conducted to analyze the effects of static or dynamic ankle ortosis produced by low-temperature or high-temperature thermoplastic plate according to 3-point force principle in combination with massage on 96 cases of congenital club foot (106 feet).
    RESULTS AND CONCLUSION: This paper focuses on the classification, materials, fundamental role and clinical effect of orthosis. Now, orthopedic materials are metal (steel and aluminum), leather, rubber, plastics and fibers. Clinical validation results within 1 year show excellent efficacy in 86 cases (93 feet), good in 8 cases (10 feet), and fair in 2 cases (3 feet). It is indicated that static or dynamic ankle ortosis produced by high-temperature thermoplastic plate for treatment of congenital club foot can obtain good early effects.

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    Nerve tissue engineering scaffolds or heterologous nerve grafts in facial nerve defects
    Ning Li-na, Xiong Ji
    2011, 15 (21):  3969-3971.  doi: 10.3969/j.issn.1673-8225.2011.21.040
    Abstract ( 143 )   PDF (516KB) ( 262 )   Save

    BACKGROUND: It is necessary for proper selection of repair methods and scaffold materials to understand repair methods of facial nerve injury and features and benefits of various scaffolds.
    OBJECTIVE: To summarize the progress in nerve tissue engineering scaffolds or heterologous nerve grafts for repair of facial nerve defects.
    METHODS: A computer search of PubMed and CNKI databases were performed using keyword of “tissue engineering scaffold, nerve transplantation, facial, repair” in Chinese and English. Totally 21 articles were reviewed.
    RESULTS AND CONCLUSION: It is the best method to directly suture nerve stump immediately after facial nerve defects. Autologous nerve grafting is limited by implant sources, which often result in denervation of the donor site. Irregular growth of extrapyramidal myelinated and non-myelinated axons can lead to the fault regeneration of nerve fibers, causing serious shortcomings associated with the movement. Allogeneic or xenogeneic neural transplantation has yielded some results, but it is still used in the research phase of animal testing, which is difficult for clinical application.

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    Effects of peroxisome proliferator-activated receptor gamma agonists on fibronectin expression after SiO2 stimulation
    Du Hai-yan
    2011, 15 (21):  3972-3974.  doi: 10.3969/j.issn.1673-8225.2011.21.041
    Abstract ( 100 )   PDF (241KB) ( 278 )   Save

    BACKGROUND: The effect and mechanism of peroxisome proliferator-activated receptor gamma (PPARγ) agonists on transforming growth factor (TGF)-β1-induced fibrotic responses in lung fibroblasts remain unclear, and seldom reported.
    OBJECTIVE: To study the effects of PPARγ agonists on TGF-β1-induced fibrotic responses in lung fibroblasts, so as to investigate its effects in preventing pulmonary interstitial fibrosis of silicosis.
    METHODS: The pulmonary alveolar macrophage was prepared with 200 mg/L SiO2 and the supernatants were got. Chinese hamster lung fibroblasts were incubated with the prepared supernatants. Then a cellular model in vitro for studying pulmonary fibrosis induced by SiO2 was developed. Chinese hamster lung fibroblasts were cultured to observe the effects of the PPARγ ligand (15 d-PGJ2) and its agonists (troglitazone and ciglitazone) on the expression of TGF-β1-induced fibronectin. RT-PCR was used to detect the mRNA expression of fibronectin and Western blotting was used to detect the protein expression of fibronectin.
    RESULTS AND CONCLUSION: (1) The expression of TGF-β1 mRNA showed an effect in a dose- (0-5 μg/L) and time-(0-24 hours) dependent manner. (2) PPARγ ligands and agonists reduced the mRNA and protein expressions of fibronectin. Results suggested that PPARγ agonists can inhibit TGF-β1-induced fibronectin synthesis after stimulation by SiO2 and may play a potential role in preventing pulmonary interstitial fibrosis.

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    Effects of trehalose on bcl-2 and bax mRNA expression in the cryopreserved sternum
    Jiang Yu-hua, Xu Lin-hao, Luo Yi-ren, Yao Ru-yong, Wang Yong-jie
    2011, 15 (21):  3975-3978.  doi: 10.3969/j.issn.1673-8225.2011.21.042
    Abstract ( 115 )   PDF (327KB) ( 323 )   Save

    BACKGROUND: Studies have demonstrated that trehalose possesses protective effects on cyropreserved sternum. But the mechanism of action remains poorly understood.
    OBJECTIVE: To investigate the effects of trehalose on bcl-2 and bax mRNA expression in cryopreserved sternum.
    METHODS: Four groups of freshly prepared solution were used: low-potassium dextran (LPD), LPD + dimethyl sulfoxide (DMSO), LPD + trehalose, LPD + DMSO + trehalose. Rat sternum was cut and then immediately cryopreserved in the tubes containing each group of solution. Fresh rat sternum tissue and 4 groups of samples cryopreserved for 120 days were taken and bcl-2 and bax mRNA expression in fresh and cryopreserved sternum was detected using reverse transcription-polymerase chain reaction.
    RESULTS AND CONCLUSION: bcl-2 mRNA expression in the LPD + trehalose group was significantly higher, but bax mRNA expression was significantly lower, than in the LPD, LPD + DMSO groups (both P < 0.01). LPD + DMSO + trehalose group showed highest bcl-2 mRNA expression and lowest bax mRNA expression, which were basically similar to fresh bone tissue   (P > 0.05). These findings indicate that trehalose may protect cell activity in cryopreserved sternum by enhancing bcl-2 mRNA expression and inhibiting bax mRNA expression, and trehalose together with DMSO shows better protective effects.

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    Comparisons of dimensional accuracy and bending resistance among four kinds of super-hard plaster casts
    Lei Dong-hui, Yang Jian-jun, An Shi-chang, Li Xiao-fei, Fu Tong-xiao, Wang Chun-fang
    2011, 15 (21):  3979-3982.  doi: 10.3969/j.issn.1673-8225.2011.21.043
    Abstract ( 552 )   PDF (311KB) ( 465 )   Save

    BACKGROUND: In the clinic, super-hard plaster is widely used for preparation of casts that can duplicate oral cavity situation, such as fixed denture and removable denture. The bending resistance of super-hard plaster can sufficiently resist the force to strip, which would avoid the fracture of tooth model. However, the symptom of tooth model fracture exists when hard material, such as polyether rubber, is used as impression material.
    OBJECTIVE: To compare the dimensional accuracy and bending resistance among four kinds of super-hard plaster: YCG, Dentona, Heraeus, and Huicheng.
    METHODS: Mental casts including three unit fixed bridge and cuboid (50 mm×10 mm×5 mm) were prepared and then poured with the above-mentioned four kinds of super-hard plaster. Then dimensional accuracy and bending resistance of the casts were measured through the use of universal tool microscope and universal testing machine. 
    CONCLUSION AND RESULTS: The proximal-distal dimensional accuracy of YCG, Dentona, Heraeus, and Huicheng super-hard plaster casts was 15.043, 15.034, 15.037 and 15.040 mm, respectively, the buccolingual dimensional accuracy was 7.020, 7.015, 7.019, and 7.019 mm, respectively, the tooth long-axis dimensional accuracy was 8.022, 8.018, 8.019, and 8.02 mm, respectively. The bending resistance of the four super-hard plaster casts was 15.687, 13.000, 22.521, 18.675 MPa, respectively. There was no significant difference in dimensional accuracy (P > 0.05), but there was significant difference in bending resistance (P < 0.01), among these four super-hard plaster casts. The bending resistance of Heraeus super-hard plaster cast was significantly greater compared with the other 3 super-hard plaster casts (P < 0.01), and the bending resistance of Huicheng super-hard plaster cast was significantly greater than that of Dentona super-hard plaster cast (P < 0.01). These findings demonstrate that Heraeus super-hard plaster has the highest bending resistance, followed by Huicheng and YCG super-hard plaster casts, and lastly Dentona super-hard plaster cast. These findings suggest that super-hard plaster cast with greater bending resistance should be chosen as possible according to practical situation.

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    Subcellular localization prediction of proteins containing fibronectin domains using collocation of amino acid pairs
    Li Li-qi, Zhang Yuan, Zhou Yue, Wang Kai-fa
    2011, 15 (21):  3983-3986.  doi: 10.3969/j.issn.1673-8225.2011.21.044
    Abstract ( 144 )   PDF (579KB) ( 300 )   Save

    BACKGROUND: Proteins containing fibronectin domains play an important role in cell migration, adhesion, growth and differentiation and have been widely applied to a variety of new biological materials. Subcellular localization prediction of proteins containing fibronectin domains can promote protein function research and development of new biomaterials.
    OBJECTIVE: To realize subcellular localization prediction of proteins containing fibronectin domains.
    METHODS: A total of 80 human proteins were randomly selected from Uniprot database. The amino acid pairs for each protein were collocated to form 400 dimensional input feature vectors. The feature vectors were then trained and tested using support vector machine and k-nearest neighbor separately. The prediction quality was examined by the jackknife test.
    RESULTS AND CONCLUSION: The prediction accuracy was 92.5% and 95% for support vector machine and k-nearest neighbor methods respectively. This suggests that support vector machine and k-nearest neighbor methods are of important significance for predicting subcellular localization of proteins containing fibronectin domains and contribute to functional research of such proteins and surface modification of new biomaterials.

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    Medical biological adhesive treatment of chylous fistula in 12 cases
    Wu Jing, Feng Yuan-yong, Jin Xiao-ming, Wang Zeng-feng, Miao Hai-ping, Yan Ping, Shang Wei
    2011, 15 (21):  3987-3990.  doi: 10.3969/j.issn.1673-8225.2011.21.045
    Abstract ( 113 )   PDF (307KB) ( 594 )   Save

    BACKGROUND: As for the treatment of chylous fistula concurrent in oral-maxillofacial tumor resection simultaneously undergoing neck lymph node dissection, many different approaches have been put forward. A simple surgical ligation, strong negative pressure drainage, filling the muscle tissue alone or a combination of the above methods are all unsatisfactory regarding the prognosis and curative effect.
    OBJECTIVE: To evaluate the validity of medical biological adhesive cohering peripheral autologous muscle tissues to block thoracic duct fistula in order to prevent chylous fistula following neck lymph node dissection.
    METHODS: All of the 12 patients were detected and diagnosed as chylous fistula in neck lymph node dissection surgery, the wounds were immediately sutured and treated with medical biological adhesive cohering peripheral autologous muscle tissues to block thoracic duct fistula.
    RESULTS AND CONCLUTION: Of all the 12 patients, 10 recovered without chylous fistula or severe complications, and reoperations were adopted to cure the failed 2 cases. All patients were visited 3 months postoperatively, no recurrence of chylous fistula, local stimulus response or allergy was found. It is suggested medical adhesive to block thoracic duct fistula may be an effective and safe way for prevent chylous fistula following neck lymph node dissection.

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