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Li D.,Shandong University | Li M.,Shandong University | Liu P.,Shandong University | Zhang Y.,Shandong University | And 2 more authors.
International Orthopaedics | Year: 2014

Purpose: Repair of bone defects, particularly critical-sized bone defects, is a considerable challenge in orthopaedics. Tissue-engineered bones provide an effective approach. However, previous studies mainly focused on the repair of bone defects in small animals. For better clinical application, repairing critical-sized bone defects in large animals must be studied. This study investigated the effect of a tissue-engineered bone for repairing critical-sized bone defect in sheep.Methods: A tissue-engineered bone was constructed by culturing bone marrow mesenchymal-stem-cell-derived osteoblast cells seeded in a porous β-tricalcium phosphate ceramic (β-TCP) scaffold in a perfusion bioreactor. A critical-sized bone defect in sheep was repaired with the tissue-engineered bone. At the eighth and 16th week after the implantation of the tissue-engineered bone, X-ray examination and histological analysis were performed to evaluate the defect. The bone defect with only the β-TCP scaffold served as the control.Result: X-ray showed that the bone defect was successfully repaired 16 weeks after implantation of the tissue-engineered bone; histological sections showed that a sufficient volume of new bones formed in β-TCP 16 weeks after implantation. Eight and 16 weeks after implantation, the volume of new bones that formed in the tissue-engineered bone group was more than that in the β-TCP scaffold group (P < 0.05).Conclusion: Tissue-engineered bone improved osteogenesis in vivo and enhanced the ability to repair critical-sized bone defects in large animals. © 2014, Springer-Verlag Berlin Heidelberg. Source

Li D.-Q.,Shandong University | Li M.,Shandong University | Liu P.-L.,Shandong University | Zhang Y.-K.,Shandong University | And 2 more authors.
Orthopedics | Year: 2014

Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the nonvascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. Source

Gao P.,PLA Fourth Military Medical University | Zhang H.,PLA Fourth Military Medical University | Xiao X.,PLA Fourth Military Medical University | Liu Y.,PLA Fourth Military Medical University | And 7 more authors.
Journal of Biomaterials and Tissue Engineering | Year: 2015

Drawbacks in traditional treatments of bone defects with autograft and allograft have prompted the exploration of tissue engineering. Bone tissue engineering generally needs exoteric cells and other growth factors and often unable to regenerate bone with the vascularization and hierarchical organization in native bone. The aim of this study was to establish an osteo-regenerator based on Beta-Tricalcium Phosphate granules which could generate bone without application of exoteric cells and growth factors. In this study, we established an ostoe-regenerator using /3-Tricalcium Phosphate granules in 1 mm-2.5 mm as the scaffold. We drilled two perforative holes in the femur of New Zealand rabbit before fixation. Two titanium alloy shields were applied to fix the whole osteo-regenerator in the femur. At 12 weeks after implantation, the osteo-regenerator was found occupied with abundant new bone. 6.9 eanwe h ri i cle, the connective tissue was seldom observed in the osteo-regenerator. This study has demonstrated that this novel osteo-regenerator can facilitate the new bone generation without any application of other exoteric cells and growth factors and can potentially serves as treatment in bone defect. © 2015 American Scientific Publishers All rights reserved. Source

Yuan J.-J.,Shanghai JiaoTong University | Xie Y.-Z.,Shanghai JiaoTong University | Han C.,Shanghai JiaoTong University | Sun W.,Shanghai JiaoTong University | And 5 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2014

Nowadays, the silver is widely used in the biological field and its biological safety catches great attention. It is important to know the distribution of silver ions within the biological organism and the toxic threshold concentration in the tissue. Therefore, a highly sensitive method for measurement of trace amount of silver ion in the medical biological samples is needed. With its high sensitivity for detection of metal ions, inductively coupled plasma mass spectrometry (ICP-MS) method is well suited for quantification of trace amount of silver ion in such samples, but method development is still in its infancy. Consequently, a simple and convenient method for determination of trace amount of silver in the animal serum, tissues or organs was developed, in which the samples were subjected to the microwave digestion, followed by the ICP-MS analysis. To begin with, the samples of serum, muscle, bone marrow, bone, heart, liver, spleen, and kidney were sequently processed in 5 mL of HNO3 and 2 mL of H2O2 solution. Then the samples were completely digested by microwave with the power of 2000 watts. The temperature was raised gradually by 3-step program. Moreover, the data achieved were reproducible and the method was time saving and especially for large amounts of sample processing. Then the digested solutions were diluted to constant volume. Finally, the concentration of 107Ag in the samples was analyzed by the method of ICP-MS under the optimized conditions. Element yttrium (Y) was used as the internal standard to compensate for matrix suppression effect and improve the accuracy of measurement. For one thing, the analytical results showed that the detection limit of the trace element 107Ag was 0.98 g·kg-1, and furthermore, the correlation coefficient of standard curve was 0.9999. For another thing, the recovery rate of the silver element ranged from 98% to 107%, which was calculated according to measured quantity before adding standard, adding standard and measured quantity after adding standard. At the same time, the relative standard deviation (RSD) of the method was in the range of 2.0%~4.3%. The concentrations of element silver in animal serum, tissues and organs were determined by the aboved method. The obtained results showed that silver ions were mainly accumulated in the liver after they were intaken into the body. The results suggested that the microwave digestion-ICP-MS method could accurately determine the trace element Ag in the body. The method developed has good feasibility and is suitable for the determination of trace element Ag in various types of medical and biological samples, especially for large quantities of biological samples. The process has the advantages of easy sample processing and it is simple and convenient. In addition, the accurate results could be obtained in a short time with high sensitivity. Last but not least, the method provides the guidance for the determination of trace elements in other biological samples. Source

Ma C.,Chinese Peoples Liberation Army | Wang Z.,PLA Fourth Military Medical University | Lu X.,South China University of Technology | Lu J.-X.,Shanghai Bio lu Biomaterials Co. | And 5 more authors.
RSC Advances | Year: 2016

In order to understand in vivo angiogenesis in a three-dimensional bone graft and the surrounding tissue penetration into the scaffolds, we implanted spherical porous β-tricalcium phosphate (β-TCP) scaffolding materials into the lumbodorsal fascia of New Zealand rabbits. At different times postoperatively, non-decalcified tissue sections were prepared and analyzed. Results showed that obvious angiogenesis accompanied the surrounding tissue penetration towards the center of implanted porous sphere. Quantitative analysis revealed that during the angiogenetic process there was a rapid increase in vessel numbers in the first 4 weeks but a significant drop afterwards, and there was a steady growth for vessel remolding (diameter expanding) after implantation. Further analysis on the distribution of vessels with different calibers indicated that small capillaries (50 μm or less in diameter) and arterioles (50-100 μm in diameter) accounted for the most part (>93.3%) while the proportion of large vessels (>100 μm in diameter) increased to 6.66% on the 12th week after implantation. In addition, we adopted a stereological method to compare angiogenesis and tissue penetration in the biomaterial implants quantitatively. With the scaffolds grafted, material biodegradation became evident in the outermost zone and was in close correlation with the increased blood vessel volume. To sum up, angiogenesis was a prerequisite for tissue penetration into the scaffolds, a process influenced by blood vessel formation and material biodegradation. © The Royal Society of Chemistry 2016. Source

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