Wang C.,Shanghai JiaoTong University |
Xue Y.,Shanghai JiaoTong University |
Lin K.,CAS Shanghai Institute of Ceramics |
Lu J.,Shanghai Bio Lu Biomaterials Co. |
And 2 more authors.
Acta Biomaterialia | Year: 2012
β-Tricalcium phosphate (β-TCP) is osteoconductive, while β-calcium silicate (β-CS) is bioactive with osteostimulative properties. Porous β-CaSiO 3/β-Ca 3(PO 4) 2 composite bioceramic scaffolds with various β-TCP:β-CS ratios were designed to combine both osteoconductivity and osteostimulation in order to enhance bone regeneration. The composite scaffolds were implanted in critical sized femur defects (6 × 12 mm) for 4, 12 and 26 weeks with pure β-TCP and β-CS scaffolds as the controls. The in vivo biodegradation and bone regeneration of the specimens were investigated using sequential histological evaluations, immunohistochemical examination and micro-computed tomography technology. The results showed that the scaffolds with 50 and 80 wt.% β-CS dramatically enhanced the amount of newly formed bone and reduced the degradation rate. In contrast, porous β-CS displayed poor new bone formation due to its rapid degradation, while porous β-TCP showed moderate bone regeneration starting on the surface of the implants, due to a lack of osteostimulation. More importantly, the scaffolds with 50 and 80 wt.% β-CS not only had excellent osteoconductivity, but also stimulated rapid bone formation, and they could degrade progressively at a rate matching the regeneration of new bone. In summary, our findings indicated that the degradation rate and bioactivity of β-CS/β-TCP composite bioceramic scaffolds could be adjusted by controlling the ratio of β-CS to β-TCP, suggesting the potential application of β-CS/β-TCP composite bioceramic scaffolds with 50 and 80 wt.% β-CS component in hard tissue regeneration and bone tissue engineering. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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.
Yuan J.,Shanghai JiaoTong University |
Wang B.,Shanghai JiaoTong University |
Han C.,Shanghai JiaoTong University |
Lu X.,Shanghai Bio lu Biomaterials Co. |
And 6 more authors.
Journal of Materials Science: Materials in Medicine | Year: 2015
The antibiotic compound, rifampicin (RFP), was loaded into porous reinforced β-tricalcium phosphate (β-TCP) scaffolds using three different solution adsorption methods. This resulted in drug delivery systems (DDS) generated by vacuum adsorption (VA), dynamic adsorption (DA), and static adsorption (SA). In vitro examination of the drug loading and release profiles of the DDS indicated that the unit mass of RFP loaded into the scaffold by the VA method (0.44 mg/g) was higher than that achieved by SA (0.42 mg/g) or DA (0.38 mg/g) (P < 0.05). The mechanical strength had no significant change after RFP-loading (P > 0.05). Moreover, there were no significant differences among the mechanical strength of three β-TCP DDS generated by loading RFP using SA, DA, and VA (P > 0.05). In vitro release testing showed an initial burst release of RFP from the three different DDS within the first 3 h and in the first 51 h, the cumulative release of RFP from VA-DDS, DA-DDS, and SA-DDS had reached 56.2, 83.6, and 88.6 %, respectively. Complete RFP release had occurred from VA-DDS, DA-DDS, and SA-DDS after 23, 17, and 15 days, respectively. As the VA-DDS method showed improved RFP loading and a more sustained drug release, this method is recommended for solution adsorption drug loading into porous β-TCP scaffolds to form a DDS. © 2015, Springer Science+Business Media New York.
Ma C.,Chinese People's 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.
PubMed | Xijing University, PLA Fourth Military Medical University and Shanghai Bio lu Biomaterials Co.
Type: | Journal: Scientific reports | Year: 2015
The porous architectural characteristics of biomaterials play an important role in scaffold revascularization. However, no consensus exists regarding optimal interconnection sizes for vascularization and its scaffold bioperformance with different interconnection sizes. Therefore, a series of disk-type beta-tricalcium phosphates with the same pore sizes and variable interconnections were produced to evaluate how the interconnection size influenced biomaterial vascularization in vitro and in vivo. We incubated human umbilical vein endothelial cells on scaffolds with interconnections of various sizes. Results showed that scaffolds with a 150 m interconnection size ameliorated endothelial cell function evidenced by promoting cell adhesion and migration, increasing cell proliferation and enhancing expression of platelet-endothelial cell adhesion molecules and vascular endothelial growth factor. In vivo study was performed on rabbit implanted with scaffolds into the bone defect on femoral condyles. Implantation with scaffolds with 150 m interconnection size significantly improved neovascularization as shown by micro-CT as compared to scaffolds with 100 and 120 m interconnection sizes. Moreover, the aforementioned positive effects were abolished by blocking PI3K/Akt/eNOS pathway with LY-294002. Our study explicitly demonstrates that the scaffold with 150 m interconnection size improves neovascularization via the PI3K/Akt pathway and provides a target for biomaterial inner structure modification to attain improved clinical performance in implant vascularization.
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.
PubMed | Xi'an Jiaotong University, PLA Fourth Military Medical University and Shanghai Bio Lu Biomaterials Co.
Type: | Journal: Scientific reports | Year: 2016
The drawbacks of traditional bone-defect treatments have prompted the exploration of bone tissue engineering. This study aimed to explore suitable -tricalcium phosphate (-TCP) granules for bone regeneration and identify an efficient method to establish -TCP-based osteo-regenerators. -TCP granules with diameters of 1mm and 1-2.5mm were evaluated in vitro. The -TCP granules with superior osteogenic properties were used to establish in vivo bioreactors, referred to as osteo-regenerators, which were fabricated using two different methods. Improved proliferation of bone mesenchymal stem cells (BMSCs), glucose consumption and ALP activity were observed for 1-2.5mm -TCP compared with 1-mm granules (P<0.05). In addition, BMSCs incubated with 1-2.5mm -TCP expressed significantly higher levels of the genes for runt-related transcription factor-2, alkaline phosphatase, osteocalcin, osteopontin, and collagen type-1 and the osteogenesis-related proteins alkaline phosphatase, collagen type-1 and runt-related transcription factor-2 compared with BMSCs incubated with 1mm -TCP (P<0.05). Fluorochrome labelling, micro-computed tomography and histological staining analyses indicated that the osteo-regenerator with two holes perforating the femur promoted significantly greater bone regeneration compared with the osteo-regenerator with a periosteum incision (P<0.05). This study provides an alternative to biofunctionalized bioreactors that exhibits improved osteogenesis.
Li W.,South China University of Technology |
Kang J.,South China University of Technology |
Yuan Y.,PLA Fourth Military Medical University |
Xiao F.,South China University of Technology |
And 6 more authors.
Composites Science and Technology | Year: 2016
The poly(vinyl alcohol) (PVA) hydrogel is regarded as a potential articular cartilage replacement for its good biocompatibility, high permeability to fluid and load-bearing properties. This work investigated a novel Poly(vinyl alcohol)-polyetheretherketone/Poly(vinyl alcohol)-β-tricalcium phosphate (PVA-PEEK/PVA-β-TCP) bilayered hydrogels by freezing-thawing with biomimetic properties for articular cartilage and subchondral bone is developed. The bilayered hydrogels microarchitecture consists of a highly porous and dense structure, and the internal structure were analyzed by micro-CT. The morphology of the resulting hydrogels was analyzed by scanning electron microscopy (SEM), the enhancement of the mechanical properties of the PVA-PEEK/PVA-β-TCP bilayered hydrogels were demonstrated by mechanical testing. The bilayered structure indicate that a good bonding exist between the two layers, which is known to be a requisite necessary to assure a good integrity and functionality of the osteochondral construct. In addition, in vitro cell culture studies revealed that the hydrogels has no negative effect on the cell viability and proliferation and possess good biocompatibility. Then, the bilayered hydrogels were implanted into the knee joint defect of rabbits and hematoxylin and eosin and immunohistochemical staining. The PVA-PEEK/PVA-β-TCP bilayered hydrogels show good potential for use in the field of articular cartilage repair. © 2016 Elsevier Ltd.
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.
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.