1.Silk fibroin/mesoporous bioactive glass ceramics repair skull defects
Zhihao GUO ; Linqiang TIAN ; Pan LIU ; Xiaotan LIU ; Hongwei WANG
Chinese Journal of Tissue Engineering Research 2017;21(2):192-196
BACKGROUND:Silk fibroin/mesoporous glass ceramic composites have been reported to exert satisfactory repair outcomes in bone defects and hold good biocompatibility. However, the biosafety and preparation methods are rarely reported. OBJECTIVE:To investigate the preparation method and treatment outcomes of silk fibroin/mesoporous bioactive glass ceramic in skul repair. METHODS:Thirty-two Sprague-Dawley rats were enrol ed to establish the skul defect models and were thenrandomized into two groups:fibroin/mesoporous glass ceramic materials and silk fibroin were respectively implanted into the defect region in experimental and control groups. At 4 and 8 weeks after implantation, the CT examination and histological observation were performed. RESULTS AND CONCLUSION:CT examination showed that at 4 weeks after implantation, the defect area in the experimental group diminished in size, showing more dense new bones. The defect area of the control group was reduced, and a smal amount of new bones were observed. At 8 weeks after implantation, bone defect repair was completed in the experimental group, but not in the control group. The bone volume in the experimental group was significantly larger than that in the control group at different time points after implantation (P<0.05). Hematoxylin-eosin staining found that at 4 weeks after implantation, in the experimental group, there was new bone between the implant and the bone, which did not cause inflammation;there were few new bones and fibrous tissues in the control group. At 8 weeks after implantation, many new bones formed in the experimental group, with similar morphology to the host bone and the scaffold was degraded completely. Conversely, the implant material stil existed in the control group. In conclusion, the silk fibroin/mesoporous glass ceramic composite can promote bone repair.
2.A genetic study of dynamic compressive stress promoting proliferation and differentiation of rat osteoblasts
Linqiang TIAN ; Fengjin GUO ; Jizhe YU ; Anmin CHEN
Chinese Journal of Physical Medicine and Rehabilitation 2012;34(3):178-181
Objective To study the impacts of dynamic compressive stress on the mRNA expression of osteopontin ( OPN ),runt related gene 2 ( Runx2 ),osteocalcin ( OC ),osterix,alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP-2) in the osteoblasts of Sprague-Dawley (SD) rats. Methods Osteoblasts extracted from skull periosteum tissue of neonatal SD rats were digested using trypsin and collagenase (Ⅰ),then were subcultured and amplified in vitro.ALP staining and alizarin red staining were performed to identify the purified cells.The cells were treated with compressive stress at 20,50 or 100 mmHg for 24 h.The expression levels of OPN,Runx-2,OC,osterix,ALP and BMP-2 were measured and quantitatively analysed using a real-time quantitative polymerase chain reaction. Results Under 20 mmHg of dynamic compressive stress the expression levels of OPN,Runx2,OC,osterix,ALP and BMP-2 all were elevated compared with the control group.The peak expression oecured under 50 mmHg pressure. The expression levels did not change significantly compared with the control group under 100 mmHg pressure. Conclusions Moderate dynamic compressive stress can promote the expression of OPN,Runx-2,OC,osterix,ALP and BMP-2 mRNA in osteoblasts,which might be an important mechanism for promoting the union of fractures.
3.Schwann cells purification by four different methods in vitro
Gang CHEN ; Caihong YANG ; Linqiang TIAN ; Fengjin GUO ; Anmin CHEN ; Kai SUN
Chinese Journal of Tissue Engineering Research 2010;14(10):1892-1896
BACKGROUND:Schwann cell is one of the major seed cells In peripheral nervous system and plays an important role in neural injury and neural disease.However,the source of Schwann cells is limited.And the purity of Schwann cells is affected due to the pollution of fibroblasts.Many purified methods have been proposed,but every one has its defect to satisfy the clinical demand.OBJECTIVE:To compare the differences among differential adhesion purified method,cold jet purified method,immunomagnetic beads selection purified method and G418 selection purified method to purify Schwann cells of neonatal rat in vitro.METHODS:Bilateral sciatic nerves of SD rats were harvested under sterile condition.Schwann cells were purified respectively using differential adhesion purified method,cold jet purified method,immunomagnetic beads selection purified method and G418 selection purified method.Cell viability was compared,and cell purity was determined by immunohistochemistry.RESULTS AND CONCLUSION:The purity of Schwann cells separated by differential adhesion method was low,but the viability was fair.The purity and viability of cells following cold jet method immunomagnetic beads selection method was high.The purity of cells separated by immunomagnetic beads selection methods was similar to that of cold jet method immunomagnetic beads selection method,but the cell viability was worse.The cell viability following G418 selection method was bad,but the purity was high.
4.Down stream involvement of the bile duct in hepatolithiasis.
Shichun LU ; Lünan YAN ; Linqiang RAO ; Tian XIA ; Jianlin GOU ; Shiyu ZHANG ; Song LEI
Chinese Medical Journal 2002;115(1):62-64
OBJECTIVETo evaluate the down stream involvement of the bile duct in hepatolithiasis.
METHODSMechanical damage to bile duct epithelia and long standing cholangitis as result of hepatolithiasis play an important role in the carcinogenesis of bile duct epithelia and stricture of the intra- and extra-hepatic bile duct. Macromorphological and microscopic changes in bile duct mucosa of 100 consecutive patients with hepatolithiasis were investigated using intra- or post-operative cholangioscopy. Biopsy specimens of lesions obtained during cholangioscopy were studied with immunohistochemical staining and flow cytometry to determine proliferative activity and DNA content. Five cases of well-proven cholangiocarcinoma were simultaneously studied as controls.
RESULTSOf the 100 patients, those with chronic cholangitis accounted for 86% (86/100), proliferative lesions 11% (11/100), adenomatous polyps 1% (1/100), and adenocarcinoma 2% (2/100). The obvious mucosal lesion associated with hepatolithiasis was located down-stream of the bile duct, predominantly in the hilar region, e.g. orifices of the right/left hepatic duct and common hepatic duct (73% mucosa lesions in the hilar region). The intensity of cancer embryonic antigen stain and the proliferative cell nuclear antigen index increased with the development of bile duct lesions. Aneuploid DNA presented mainly in the high degree malignant adenocarcinomas (> 80% of cases).
CONCLUSIONSThe obvious mucosal lesions associated with hepatolithiasis were located down-stream of the bile duct, predominantly in the hilar region (73% of mucosal lesions). The proliferative activity of examined bile duct mucosa lesions increased with the development of pathological deterioration, which may contribute to the development of hilar bile duct stricture and hilar cholangiocarcinoma.
Adult ; Aged ; Bile Ducts ; pathology ; Carcinoembryonic Antigen ; analysis ; Cholangiocarcinoma ; etiology ; Humans ; Lithiasis ; complications ; pathology ; Liver Diseases ; complications ; pathology ; Middle Aged ; Proliferating Cell Nuclear Antigen ; analysis