1.Enrichment of lung cancer stem cells and expression of related markers
Chinese Journal of Tissue Engineering Research 2015;(14):2167-2171
BACKGROUND:Lung cancer stem cel s are tightly related to the treatment and prognosis of lung cancer. We can provide more references for clinical diagnosis and treatment of lung cancer through the study on the tumorigenicity and surface markers of lung cancer stem cel s. OBJECTIVE:To explore the enrichment methods for lung cancer stem cel s and cel ular tumorigenicity. METHODS:Lung cancer stem cel s were induced in serum-free culture medium containing epidermal growth factor, insulin-like growth factor 1, and basic fibroblast growth factor. Then, the expressions of related surface markers were detected using immunofluorescence method. After that, mice were implanted subcutaneous with lung cancer stem cel spheres to understand the tumorigenicity of lung cancer stem cel s. RESULTS AND CONCLUSION:Lung cancer stem cel s under serum-free induction and culture were changed to sphere-forming cel s, and the immunofluorescence detection showed that over 80%of sphere-forming cel s were positive for CCSP, SP-C and OCT4. After transplantation of sphere-forming cel s, the mice showed a high tumorigenicity. These findings indicate that sphere-forming cel s are formed after serum-free suspension culture of lung cancer stem cel s, which have a higher tumorigenicity.
6.Management of primary vesicoureteral reflux in children.
Yan CHEN ; Jie DING ; Jian-ping HUANG
Chinese Journal of Pediatrics 2004;42(10):750-752
9.Biodegradation of a novel bionic scaffold with nanostructure in vivo
Jianhong CHEN ; Qian TANG ; Huanyou LIANG ; Ping WANG ; Jian WU
Chinese Journal of Tissue Engineering Research 2009;13(25):4977-4980
BACKGROUND: Bone implant materials have been previously reported to be not coincident between inducing velocity of new bone formation and degradation velocity itself; therefore, the materials could not be completely degraded but formed into foreign substances. A novel artificial bone implant material, characterizing by well biocompatibUity, biodegradation, and biomechanics, is focused in biomaterials field recently.OBJECTIVE: To study the biodegredation of a novel bionic scaffold with nanostructure, i.e., poly (3-hydroxybutyrate-co-3-hydroxyvalerata)/sol gel bioactive glass (PHBV/SGBG), in vivo. DESIGN, TIME AND SETTING: A controlled animal experiment was performed at Animal Experimental Center of the Third Hospital affiliated to Sun Yat-sen University from May 2005 to October 2006. MATERIALS: PHBV/SGBG was provided by Materials Institute of South China University of Technology, and ethylene oxide was sterilized for preparation.METHODS: Eight hybrid dogs were used to make models of Ubia diaphyseal defect, having two defects on both left and right sides. The tibia diaphyseal defects at proximal part were considered as the control group, and those were not performed with any treatment; while, the tibia diaphyseal defects at distal part were considered as the experimental group, and PHBV/SGBG was fully implanted into the defect regions. Every two dogs were sacrificed at different time points of 2, 4, 8, and 12 weeks, respectively. MAIN OUTCOME MEASURES: In vivo biodogradation and osteogenesis were monitored under optic microscopy and electron microscope.RESULTS: The PHBV/SGBG scaffold had well biodegradation and rapid degradation velocity, and it began to degrade at two weeks after operation. The PHBV/SGBG scaffold was almost replaced by new bone tissues at 8 weeks after operation and completely degraded at 12 weeks after operation. In addition, the PHBV/SGBG scaffold had a good ability to induce new bone formation from edge to center. Whereas, surface depression in the defect region was still visible in the control group, cortical bone was not formed in embedded region of soft tissue; furthermore, electron microscopy demonstrated that calcium salt deposition was increased in the bone defect region, and the structure was tight; however, the defect was not completely repaired, and some voids were still visualized.CONCLUSION: The novel bionic scaffold, PHBV/SGBG, degrades fast in vivo to generate new bone tissues. The new bone regenerate accompanied by a fitting degradation of the novel bionic scaffold that achieve complete repair.
10.Experimental research on porous titanium implant fabricated by three-dimensional printing with different sintering temperatures
Jian SUN ; Yaoyang XIONG ; Ping CHEN ; Fuqiang ZHANG
International Journal of Biomedical Engineering 2012;(6):332-336,342
Objective The aim of this study was to evaluate the feasibility of three-dimensional printing (3DP) for the preparation of porous titanium implant and to investigate the impacts on microstructure and mechanical properties with different sintering temperatures.Methods The CAD model of the specimens was designed to be 25 mm in diameter,20 mm in height,and with 0.5 mm pore size mesh.On every cross-section,80% bonding area was designed.Titanium powder (purity of 98.5%,75 μm diameter) was selected as raw material.Polyvinyl alcohol powder (160 μm diameter) was selected as a binder,and polyvinylpyrrolidone powder was selected as an auxiliary binder.The green porous titanium implants were fabricated by 3DP followed by sintering at 1 200,1 300,1 400 ℃,separately,under the protection of argon gas.After sintering,the properties of porous titanium implants were evaluated,including the porosity,microstructure,microhardness,compressive strength and elastic modulus.Results After sintering,the specimen had uniform contraction and no obvious distortion.The specimen sintered at 1 200,1 300 and 1 400 ℃ sintering temperatures had porosity of (65.01±1.03)%,(46.73±0.73)% and (41.06±0.31)%,hardness of 115.2±0.6,148.6±1.1 and 182.8±2.1,elastic modulus of (5.9±0.5),(16.2±0.9) and (34.8±1.5) GPa,compressive strength of (81.3±4.3),(135.4±8.5) and (218.6±7.1) MPa,respectively.A porous structure with three-dimensional network of connected pores was observed under scanning electron microscope.Conclusion It is feasible to fabricate porous titanium implants by three dimensional printing technique.The mechanical properties of the porous titanium implants match well with bone tissue which has excellent biomechanical compatibility.