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ABSTRACT: Abstract Background: Calcitonin gene-related peptide (CGRP) is a neuropeptide distributed in bone tissue involved in bone remodeling. Previously we demonstrated that CGRP can promote proliferation and migration of endothelial cells, relating to the expression of vascular endothelial growth factor (VEGF) and focal adhesion kinase (FAK). Methods: CGRP1 receptor expression in human umbilical vein endothelial cells (HUVECs) was examined by immunofluorescence microscopy and real-time PCR. Tube formation was measured by a Matrigel tube formation assay. VEGF protein and mRNA levels were quantified by ELISA and real-time PCR, respectively. The expression of VEGF receptor 1 (FLT1) and VEGF receptor 2 (KDR) were measured by real-time PCR and immunoblotting assays. Results: CGRP significantly induced vascular tube formation of outgrowth HUVECs in a Matrigel. The expression of FLT and KDR were significantly increased by CGRP, and CGRP enhanced the expression of CGRP1 receptors. Compared to the known angiogenesis regulator VEGF165, CGRP had an equal or stronger effect on migration and tube formation, but not on proliferation of endothelial cells. The upregulation of calcitonin receptor-like receptor (CRLR), FAK, VEGF and its two main receptors (FLT1, KDR) by CGRP was also more pronounced than that obtained by VEGF165. Conclusion: It is concluded that CGRP is a strong proangiogenic growth factor, thereby contributing to bone development and remodeling by promoting angiogenesis.
Journal of Receptor and Signal Transduction Research 03/2013; · 1.59 Impact Factor
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ABSTRACT: OBJECTIV: To explore the value of three-dimensional digital reconstruction techniques in the diagnosis and treatment of proximal humeral fractures.
From January, 2008 to May, 2010, 25 patients with proximal humeral fractures underwent preoperative examinations with conventional X-ray, plain CT scan and 3D-CT scan. Based on the two-dimensional gray-scale CT scan data in DICOM format, personalized virtual fracture models were reconstructed using Amira4.1 software and compared with the conventional imaging examination methods for fracture typing to identify the fracture classification. Personalized surgical treatment was implemented according to the typing of the fractures, and the patients were followed up postoperatively for 8 to 35 months (mean 21 months) for functional evaluation using the Constant-Murley score.
In the 25 cases of proximal humeral fractures, plain X-ray examination obtained a clear diagnosis and classification of the fractures in 15 cases, and CT scan, three-dimensional CT, and personalized three-dimensional model reconstruction confirmed the diagnosis and classification in 20, 22, and 25 cases, respectively. The humeral fractures healed generally 6 months after the operation, and the patients showed a Constant-Murley score ranging from 70 to 100 (mean 88).
Preoperative personalized three-dimensional reconstruction of proximal humeral fracture can help obtain a more accurate diagnosis of the fracture type to facilitate the decision on the optimal surgical plan, surgical approach and internal fixation methods.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 11/2012; 32(11):1671-4.
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ABSTRACT: Autologous platelet rich plasma (PRP) has been extensively investigated for large bone defect treatment, but its clinical application is harassed by controversial outcome, due to highly variable PRP quality among patients. Alternatively, allogeneic PRP from well-characterized donors can not only generate more consistent and reliable therapeutic effect, but also avoid harvesting large quantities of blood, an additional health burdens to patients. However, the use of allogeneic PRP for bone defect treatment is generally less investigated, especially for its immunogenicity in such application. Here, we meticulously investigated the immunogenicity of allogeneic PRP and evaluated its healing efficacy for critical sized defects treatment. Allogeneic PRP contained 4.1 folds and 2.7-4.9 folds higher amount of platelets and growth factors than whole blood respectively. The intramuscular injection of allogeneic PRP to rabbits did not trigger severe and chronic immuno-response, evidenced by little change in muscular tissue microstructure and CD4+ /CD8+ T lymphocyte subpopulation in peripheral blood. The implantation of allogeneic PRP/ deproteinized bone matrix (DPB) constructs(PRP+DPB) successfully bridged 1.5 cm segmental radial defects in rabbits, achieving similar healing capacity as autologous MSC/ DPB constructs (MSC+DPB), with greater bone formation (1.1-1.5x, p<0.05) and vascularization (1.3-1.6x, p<0.05) than DPB alone, shown by histomorphometric analysis, bone mineral density measurement and radionuclide bone imaging. Furthermore, the implantation of both allogeneic PRP and autologous MSC mediated DPB constructs (PRP+MSC+DPB) resulted in the most robust bone regeneration (1.2-2.1x, p<0.05) and vascularization (1.3-2.0x, p<0.05) than others (PRP+DPB, MSC+DPB or DPB alone). This study has demonstrated the promising use of allogeneic PRP for bone defect treatment with negligible immunogenicity, great healing efficacy, potentially more consistent quality and no additional health burden to patients; additionally, the synergetic enhancing effect found between allogeneic PRP and autologous MSCs may shed a light on developing new therapeutic strategies for large bone defect treatment.
Cell Transplantation 08/2012; · 5.13 Impact Factor
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ABSTRACT: To explore the characteristics of the talonavicular joint movement in vivo and its effects on changes of the medial longitudinal arch.
Foot CT images in the initial position (neutral position) and terminal position (maximum varus-adduction-dorsiflexion position) were acquired from 9 cases (5 healthy volunteers, including 4 males and 1 female) during foot varus-adduction-dorsiflexion motion. Based on the principle of rigid body kinematics, the CT data were reconstructed and analyzed with Mimics and Geomagic reverse engineering software. The changes of the talonavicular joint in three-dimensional in 6 degrees of freedom were calculated to determine its correlation to the medial longitudinal arch angle.
During foot varus-adduction-dorsiflexion motion, the talonavicular joint underwent varus-adduction-plantarflexion motion, with the motion range of 38.82∓5.98° in varus, 19.71∓6.33° in adduction, and -5.09∓6.89° in plantarflexion. During talonavicular joint motion, the medial shift of the navicular was significantly correlated to the changes of foot medial longitudinal arch (P<0.05).
Digital technology can solve the problem of measurement of talonavicular joint three-dimensional motion in vivo. Though as a ball-and-socket joint, the talonavicular joint mainly rotates around the sagittal axis, and its movement is a major factor to cause changes of foot medial longitudinal arch.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 05/2012; 32(5):622-6.
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Tao Wu,
KaiHui Nan,
JingDi Chen, Dan Jin,
Shan Jiang,
PeiRan Zhao,
JunChang Xu,
Hao Du,
XiaoQiang Zhang,
JianWei Li,
GuoXian Pei
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ABSTRACT: Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone tissue engineering. A new
bone repair scaffold was generated by thorough mixing of icariin and chitosan/hydroxyapatite (icariin-CS/HA) using freeze-drying
technigue. Characteristics of morphology, mechanical properties, biocompatibility, drug release behavior and bone repair abilities
in vivo were evaluated. The results show that drug loading process of icariin did not affect physical structure of CS/HA composite
significantly but decreased mechanical properies of CS/HA composite, which happened with a high dosage; icariin-CS/HA had
favorable cell compatibility and promoted osteogenic differentiation of hBMSCs; the controlled release of icariin was satisfactory
and the release retained after 90 d in vitro. In addition, icariin-CS/HA scaffolds had favorable osteoconduction and osteoinduction in vivo, and could fill bone defect sites and stimulate newborn bone tissues formation at early stage. On the basis of these data,
icariin-CS/HA is believed to be an optical bone repair scaffold for tissue engineering.
Chinese Science Bulletin 04/2012; 54(17):2953-2961. · 1.32 Impact Factor
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ABSTRACT: Tissue engineered bone implanted with sensory nerve can effectively promote angiogenesis and repair of bone defects. To investigate the effects of calcitonin gene-related peptide (CGRP) on proliferation and migration of human umbilical vein endothelial cells (HUVECs) for further revealing the mechanism of tissue engineered bone implanted with sensory nerve promoting angiogenesis.
HUVECs were collected from human umbilical core, and identified through von Willebrand factor (vWF) and CD31 immunofluorescence. The HUVECs were treated with CGRP and were divided into 6 groups according to CGRP concentration: group A (0 mol/L), group B (1 x 10(-12) mol/L), group C (1 x 10(-11) mol/L), group D (1 x 10(-10) mol/L), group E (1 x 10(-9) mol/L), and group F (1 x 10(-8) mol/L). The expression of the CGRP1 receptor (CGRP1R) was observed in HUVECs by cell immunofluorescence. The growth rate of HUVECs was detected throug AAlarmarBlue at 1, 2, 3, 4, and 5 days. Transwell chamber was used to detect the ability of cell migration. ELISA assay was used to detect the vascular endothelial growth factor (VEGF) secretion and the protein expression of focal adhesion kinase (FAK) was examined using Western blot.
HUVECs were identified through morphology, vWF and CD31 immunofluorescence. HUVECs expressed CGRP1R. CGRP could stimulate HUVECs proliferation in a time- and concentration-dependent manners; the cell growth rates of groups B-F were significantly higher than that of group A at all time (P < 0.05); group F had highest cell growth rate. The number of cell migration of group B-F was significantly higher than that of group A (P < 0.05), which increased more than 3 times. Groups B-F had higher amount of VEGF than group A (P < 0.05), and groups C and D had highest amount of VEGF. FAK expression of groups B-F was significantly increased at 3, 7, and 10 days after CGRP treatment when compared with group A (P < 0.05).
CGRP may enhance the proliferation and migration of HUVECs by increasing the secretion of VEGF and expression of FAK.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 04/2012; 26(4):495-500.
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ABSTRACT: Aim: We conducted the present study to assess health-related quality of life (HRQoL) among bone cancer patients after surgical treatment in one large teaching hospitals in China, and assess the risk factors for improving the physical or mental HRQoL. Methods: 344 eligible adult patients who were admitted to the hospital with malignant bone tumors during the period of Jun. 2008 to Dec. 2011, and a reference group with 361 health cases was recruited in the same hospital during the same period. All 344 patients were followed up for one year. The HRQoL before treatment and after one year was evaluated with the Medical Outcome Short Form 36 (SF-36). Results: All 8 domains of HRQoL had the lowest scores greatly improved over the first year after discharge. However, the patients still had significantly lower scores in every domain than the reference group one year after discharge. Age and type of surgery were associated with HRQoL in the mental domain. Conclusion: The HRQoL of patients with malignant bone tumors greatly improved one year after the treatment. This study also highlighted the utility of HRQoL assessment for prognostic evaluation of patients after surgical treatment for bone cancer.
Asian Pacific journal of cancer prevention: APJCP 01/2012; 13(7):3099-102. · 0.66 Impact Factor
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ABSTRACT: Osteonecrosis of the femoral head (ONFH) is generally characterized as an irreversible disease and tends to cause permanent disability. Therefore, understanding the pathogenesis and molecular mechanisms of ONFH and developing effective therapeutic methods is critical for slowing the progress of the disease.
In this study, an experimental rabbit model of early stage traumatic ONFH was established, validated, and used for an evaluation of therapy. Computed tomography (CT) and magnetic resonance (MR) imaging confirmed that this model represents clinical Association Research Circulation Osseous (ARCO) phase I or II ONFH, which was also confirmed by the presence of significant tissue damage in osseous tissue and vasculature. Pathological examination detected obvious self-repair of bone tissue up to 2 weeks after trauma, as indicated by revascularization (marked by CD105) and expression of collagen type I (Col I), osteocalcin, and proliferating cell nuclear antigen. Transplantation of hepatocyte growth factor (HGF)-transgenic mesenchymal stem cells (MSCs) 1 week after trauma promoted recovery from ONFH, as evidenced by a reversed pattern of Col I expression compared with animals receiving no therapeutic treatment, as well as increased expression of vascular endothelial growth factor.
These results indicate that the transplantation of HGF-transgenic MSCs is a promising method for the treatment for ONFH and suggest that appropriate interference therapy during the tissue self-repair stage contributes to the positive outcomes. This study also provides a model for the further study of the ONFH etiology and therapeutic interventions.
PLoS ONE 01/2012; 7(5):e37503. · 4.09 Impact Factor
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ABSTRACT: Icariin, a plant-derived flavonol glycoside, has been proved as an osteoinductive agent for bone regeneration. For this reason, we developed an icariin-loaded chitosan/nano-sized hydroxyapatite (IC-CS/HA) system which controls the release kinetics of icariin to enhance bone repairing. First, by Fourier transform infrared spectroscopy, we found that icariin was stable in the system developed without undergoing any chemical changes. On the other hand, X-ray diffraction, scanning electron microscopy and mechanical test revealed that the introduction of icariin did not remarkably change the phase, morphology, porosity and mechanical strength of the CS/HA composite. Then the hydrolytic degradation and drug release kinetics in vitro were investigated by incubation in phosphate buffered saline solution. The results indicated that the icariin was released in a temporally controlled manner and the release kinetics could be governed by degradation of both chitosan and hydroxyapatite matrix. Finally the in vitro bioactivity assay revealed that the loaded icariin was biologically active as evidenced by stimulation of bone marrow derived stroma cell alkaline phosphatase activity and formation of mineralized nodules. This successful IC-CS/HA system offers a new delivery method of osteoinductive agents and a useful scaffold design for bone regeneration.
Journal of Materials Science Materials in Medicine 11/2011; 23(2):399-407. · 2.32 Impact Factor
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ABSTRACT: The aim of the study is to evaluate the surgical technique and clinical significance of the sequential therapy of vacuum sealing drainage (VSD) and free-flap transplantation for children with extensive soft-tissue defects below the knee in the extremities.
Twenty-two children (aged from 3 to 10 years) received sequential therapy of VSD and free-flap transplantation. All cases suffered from extensive area soft-tissue defects and exposure or partial defects of bones, tendons and other deep tissues. The wound sizes varied from 10 cm × 6 cm to 30 cm × 22 cm. Amongst 22 cases, 12 cases had fresh wounds and the remaining 10 children had necrotising infection. After complete debridement, the wounds were covered by VSD. External fixation or Kirschner-wire fixation should be performed for the cases complicated by unsteady fractures. After the removal of negative pressure VSD devices, free-flap transplantations were performed in 8 cases after debridement, and 14 cases received combined therapy of free-flap transplantation and skin grafting depending upon the severity of soft-tissue and deep-tissue defects. The flap survival and wound healing were followed up postoperatively.
After VSD treatment, the infection of deep-tissue exposure was effectively prevented, and granulation tissues surrounding the exposed areas of tendons and bones grew well. All patients who received free-flap transplantation at the second stage survived without the occurrence of vascular crisis, infection or sinus formation. During follow-up ranging from 6 to 24 months, all the patients were satisfied with the morphological appearance and functional recovery of the affected limbs.
Sequential therapy of VSD and free-flap transplantation can serve as a reliable option for children with extensive soft-tissue defects below the knee in the extremities and exposed deep tissues, after complete debridement, which significantly shortens remedy period, enhances success rate for surgery and achieves maximal restoration of limb function.
Injury 11/2011; 43(6):822-8. · 1.98 Impact Factor
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ABSTRACT: To explore the effects of calcitonin gene-related peptide (CGRP) on the migration of bone marrow mesenchymal stem cells (BMSCs) and vascular endothelial growth factor (VEGF) expression in vitro.
The BMSCs were isolated from Sprague Dawley rats using whole bone marrow adherence method. At 1, 2, and 3 weeks after culture, the expressions of CGRP receptor (CGRPR) was detected by Western blot. The BMSCs were treated with CGRP at concentration 1 x 10(-8) mol/L (experimental group) and did not treated (control group), and the efficacy of BMSCs migration was analyzed by Transwell chamber assay after 72 hours; at 1, 3, 5, and 7 days, the mRNA expressions of vascular cell adhesion molecule 1 (VCAM-1) were detected by real-time fluorescent quantitative PCR; the protein expressions of VEGF were examined using immunohistochemistry and Western blot.
CGRPR expressed stably in the cultured BMSCs and reached the peak at 2 weeks. CGRP had a significantly enhanced role in promoting cell migration. The number of cell migration was (3.20 +/- 1.77) cells/HP in experimental group and (1.11 +/- 0.49) cells/HP in control group, showing significant difference (t = 4.230, P = 0.001). In experimental group, the expressions of VCAM-1 mRNA increased with time and reached the peak at 7 days. There were significant differences in the expressions of VCAM-1 mRNA between control group and experimental group at 3, 5, and 7 days (P < 0.05). Immunocytochemistry results showed positive DAB staining for VEGF at 5 and 7 days in experimental group. Western blot results showed that the protein expressions of VEGF increased significantly at 5 and 7 days in experimental group when compared with control group (P < 0.05), which was signfiantly higher at 5 days than at 7 days in experimental group (P < 0.05).
CGRP can promote the migration of BMSCs and stimulate the protein expression of VEGF, which may plays an important role in regulating bone metabolism by increasing angiogenesis.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 11/2011; 25(11):1371-6.
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ABSTRACT: Cartilage injury has a very poor capacity for intrinsic regeneration. The cell-based treatment strategy for the cartilage repair using differentiated bone marrow mesenchymal stem cells (BMSCs) is, however, a promising approach to the chondral repair. This study was aimed to explore the chondrogenic potential of the goat BMSCs in the Transwell co-culture system and the poly-laetide-co-glycolide (PLGA) scaffolds.
The BMSCs were isolated from the goat iliac crest while the chondrocytes were obtained from the goat's last costal cartilage. In the Transwell co-culture system, the BMSCs co-cultured with chondrocytes were designed as group A, whereas the goat's BMSCs induced with the chondrogenic medium were group B. Both groups A and B were the experimental groups, while group C that only contained BMSCs was the control group. In the PLGA scaffolds co-culture system, BMSCs were seeded into the PLGA scaffolds, which were suspended in the 24-well plate, and the control group was established by presence or absence of chondrocytes at the bottom of the 24-well plate. Toluidine blue staining, Alcian blue staining, collagen II immunofluoresence, collagen II immunochemical staining, collagen I, collagen II, COL2a Q-PCR and osteopontin Q-PCR were used to examine the chondrogenic conditions as well as the expressions of chondrogenic and osteogenic genes.
Cells isolated from the aspirates of the goat bone marrow proliferated rapidly and gained characteristics of stem cells in Passage 4. However, the differentiations of chondrocytes were not apparent in Passage 3. The results from Toluidine blue staining, collagen II immunofluoresence and PCR showed the transformation of BMSCs to chondrocytes in the Transwell co-culture system and PLGA scaffolds. Although the cartilage gene expressions were upgraded in both chondrogenesis group and co-culture system, the osteopontin gene expression, which represents osteogenic level, was also up-regulated.
The Transwell co-culture system and the PLGA scaffolds co-culture system can promote the chondrogenic differentiation of the goat's BMSCs, while up-regulated osteopontin gene expression in the Transwell co-culture system implies the osteogenic potential of BMSCs.
Chinese medical journal 10/2011; 124(19):3080-6. · 0.86 Impact Factor
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ABSTRACT: To review the recent progress of the researches in construction of tissue engineered osteochondral composites, and to discuss the challenges in construction of tissue engineered osteochondral composites.
The recent literature on the construction of tissue engineered osteochondral composites was extensively reviewed and analyzed.
The studies on the construction of tissue engineered osteochondral composites are relatively more in vivo, the current focus is that different tissues derived mesenchymal stem cells are widely used to be seed cells; single-phase scaffold has been limited, studies on biphase scaffold and triphase scaffold are new trends; the design and performance of bioreactor need to be further optimized in the future.
The construction of tissue engineered osteochondral composites will be a promising method for the treatment of cartilage defects.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 09/2011; 25(9):1120-4.
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ABSTRACT: Icariin had been reported as a potential agent for osteogenesis, but the dose-effect relationship needed further research to realize the clinical application of icariin. We isolated and purified human bone mesenchymal stem cells (hBMSCs) and stimulated them with different concentrations of icariin. The cytotoxicity of icariin was evaluated by the methylthiazolytetrazolium (MTT) assay method. The proliferation and osteogenic differentiation of such hBMSCs were investigated for different concentrations of icariin. We found that icariin had a dose-dependent effect on the proliferation and osteogenic differentiation of hBMSCs in a suitable concentration range from 10(-9) M to 10(-6) M, but at concentrations above 10(-5) M, the cytotoxicity limited its use. The extremely low cost of icariin and its high abundance make it appealing for bone regeneration.
Molecules 01/2011; 16(12):10123-33. · 2.39 Impact Factor
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ABSTRACT: Although vascularized tissue-engineered bone grafts (TEBG) have been generated ectopically in several studies, the use of prevascularized TEBG for segmental bone defect repair are rarely reported. In current study, we investigated the efficacy of prevascularized TEBG for segmental defect repair. The segmental defects of 15 mm in length were created in the femurs of rabbits bilaterally. In treatment group, the osteotomy site of femur was implanted with prevascularized TEBG, which is generated by seeding mesenchymal stem cells (MSCs) into β-TCP scaffold, and prevascularization with the insertion of femoral vascular bundle into the side groove of scaffold; whereas in the control group, only MSC mediated scaffolds (TEBG) were implanted. The new bone formation and vascularization were investigated and furthermore, the expression of endogenous vascular endothelial growth factor (VEGF) which might express during defect healing was evaluated, as well. At 4, 8, and 12 weeks postoperatively, the treatment of prevascularized TEBG led to significantly higher volume of regenerated bone and larger amount of capillary infiltration compared to non-vascularized TEBG. The expression of VEGF in mRNA and protein levels increased with implantation time and peaked at 4 weeks postoperatively, followed by a slow decrease, however, treatment group expressed a significant higher level of VEGF than control group throughout the whole study. In conclusion, this study demonstrated that prevascularized TEBG by insertion of vascular bundle could significantly promote the new bone regeneration and vascularization compared to non-vascularized TEBG, which could be partially explained by the up-regulated expression of VEGF.
Biomaterials 12/2010; 31(36):9452-61. · 7.40 Impact Factor
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ABSTRACT: Deep-freezing, freeze-drying and gamma (γ)-irradiation have deleterious effects on bone healing and mechanical properties of allograft bones. We tried preparing bone allografts using cyclosporine plus low-temperature-plasma sterilization. To explore the feasibility of this method of preparation, segmental defects in the right radii of rabbits were repaired with cyclosporine-impregnated allograft bones (CABs) sterilized with low-temperature-plasma (in the study group) and deep-frozen/freeze-dried irradiated allograft bones (D/FIABs) (in the control group). X-ray and quantitative histological analysis, peripheral blood T lymphocyte subset analysis and CD₂₅ molecule immunohistochemistry stain, the four-point bending test and safety evaluations were respectively conducted to compare bone-healing, immunosuppression, mechanical properties and safety between the two groups. X-ray scores were higher in the study group than those in the control (p = 0.032). There were significant differences in new bone areas at most repairs in both groups (p < 0.05). There were no significant differences in the percentages of CD₄(+) T, CD₈(+) T, ratios of CD₄(+) T:CD₈(+) T or serum concentrations of GPT/Cr in both groups (p > 0.05). At 16 weeks postoperatively, the density of CD₂₅ molecules in the control group was higher than that in the study group. The ultimate loading in the study group was significantly higher than that in the control (p = 0.048). Bone marrow stromal cells (BMSCs) grew thickly around and on the surface of a cyclosporine-impregnated allograft. Livers and kidneys in the study and control groups remained histologically normal at 7 days postoperatively. These results indicate that the CAB might be a better material than the D/FIAB in terms of bone healing, preservation of mechanical properties and immunosuppression without severe side-effects.
Journal of Tissue Engineering and Regenerative Medicine 12/2010; 4(8):638-51. · 3.28 Impact Factor
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ABSTRACT: We investigated whether implantation of vascular bundles or sensory nerves affected the expression of calcitonin gene-related peptide type I receptor (CGRP1R) and neuropeptide Y1 receptor (NPY1R) in tissue-engineered bone. We implanted osteogenically induced bone marrow mesenchymal stem cells (BMSCs) with β-tricalcium phosphate (β-TCP) as the scaffold material either with sensory nerve tracts (group I, n = 18), vascular bundles (group II, n = 18) or alone (group III, n = 18) to repair a 1.2 cm femur defect in the rabbit. Better osteogenesis was observed by x-ray and histology in groups I and II than in group III at 4, 8 and 12 weeks. Within the new bone, the mRNA levels of the two neuropeptide receptors determined by real-time PCR increased through week 8, and then gradually decreased (P < 0.05). Expression of the neuropeptide receptors determined by immunohistochemistry was lowest at 4 weeks (P < 0.05) and was higher in group II than in group I (P < 0.05). Expression was significantly higher in groups I and II than in group III at all time points. We conclude that implanting vascular bundles into tissue-engineered bone can significantly improve the early expression of CGRP1R and NPY1R. In contrast, implantation of sensory nerves did not show the same dramatic effect as implantation of vascular bundles.
Biomedical Materials 10/2010; 5(5):055002. · 2.16 Impact Factor
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ABSTRACT: To investigate the effectiveness and mechanism of tissue engineering vascularized bone in repairing segmental femoral bone defects in rabbits.
Thirty-two rabbits were randomized into two groups (n = 16 each). A segmental and critical bone defect of 15 mm in length was made at left femur. In experimental group, the tissue engineering bone constructed from autologous bone marrow mesenchymal stem cells plus beta-tricalcium phosphate (beta-TCP) and vascular bundle was implanted into bony defect. In control group, there was no implantation of vascular bundle. Animals were sacrificed at 2, 4, 8 and 12 weeks post-implantation respectively. Histological observation was conducted to determine the process of new bone formation and remodeling. The expression of vascular endothelial growth factor (VEGF) in new bone was measured by immunohistochemistry, real-time PCR and Western blot.
As indicated by histological observations over time, new bone formation increased in both groups. It was better in the experimental group than the control group at the beginning of 4 weeks. The expression level of VEGF gradually decreased in each group after an initial rise. And the expression of VEGF was significantly higher than the control group after implantation at all time points and peaked at 4 weeks.
Tissue engineering vascularized bone accelerates bone repair in critical size defect model of femur in rabbit. Implantation of vascular bundle can promote the secretion of VEGF. And VEGF is an essential mediator of both angiogenesis and ossification.
Zhonghua yi xue za zhi 06/2010; 90(23):1637-41.
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ABSTRACT: OBJECTIVE To explore the cytotoxicity, labeled time, marking rate, and effect on adhesion of quantum dot 655 (QD655) labeled rat bone marrow mesenchymal stem cells (BMSCs) in vitro, and to confirm its feasibility for stem cell labeling and tracer means for rat.
BMSCs were collected from the femur and tibia bone marrow cavity of a 2-week-old SD rat, cultured and identified. The 3rd passage of BMSCs were incubated with QD655 as the experimental group according to the recommended concentration of the markers. The cells were not labeled by QD655 as control group. The cell survival rate after QD655 labeling was detected by trypan-blue exclusion. The effect of QD655 on cell proliferation was observed by MTT. The osteogenic differentiation potential was identified by Alizarin red staining, alkaline phosphatase (ALP) staining, and real-time fluorogenic quantitative PCR. At immediately, 1, 2, 4, and 6 weeks, fluorescent microscopy was used to observe the labeled rate and scanning electron microscope was used to observe the cell adhesion to scaffold (bioglass/collagen composite).
The cell survival rates were more than 90% in both experimental group and control group, showing no significant difference (P > 0.05). There was no significant difference in the cell proliferation between 2 groups (P > 0.05). Alizarin red staining and ALP staining showed positive results. Real-time fluorogenic quantitative PCR result showed that the mRNA expression levels of osteopontin, osteocalcin, collagen type I, ALP, and BMP-2 in the experimental group was significantly higher than those in the control group. The labeled rates were 96.50% +/- 1.59%, 93.30% +/- 1.51%, 72.40% +/- 2.90%, 40.10% + 3.60%, and 10.00% +/- 1.70% immediately, 1, 2, 4, and 6 weeks after labeling, respectively. The labeled rate in the control group was 0. Scanning electron microscope showed a good distribution of fusiform or polygonal cells in the pores of scaffold.
QD655 can be used as a labeling marker for BMSCs. Rat BMSCs labeled with QD655 is of high efficiency and safety.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 06/2010; 24(6):744-8.
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ABSTRACT: To establish a computer-aided three-dimensional visualization operation simulation system based on Mimics and Unigraphics NX software to provide reliable evidence for accurate preoperative surgical planning.
The preoperative CT scans of 5 patients with intertrochanteric fractures were used for three-dimensional reconstruction of intertrochanteric fractures using Mimics software. Three-dimensional reconstruction of the surgical instruments was carried out using the modeling function of Unigraphics NX software, whose assembly function was used to visualize the simulates internal fixations of intertrochanteric fractures with dynamic hip screw (DHS) system. The operative procedures simulated by Unigraphics NX were analyzed preoperatively.
The virtual surgery procedures were clearly and vividly visualized in three dimensions. The fracture reduction and surgical effects could be predicted using this system.
This system of three-dimensional visualization of virtual surgery for intertrochanteric fractures has important values in surgical planning, risk assessment and clinical training, and can help improve the reliability and outcome of orthopedic surgery.
Nan fang yi ke da xue xue bao = Journal of Southern Medical University 05/2010; 30(5):1165-8.
