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OBJECTIVE: To investigate the effects of human cerebrospinal fluid (CSF) during development phase on migration and differentiation of fetal brain neural stem cells (NSCs).METHODS: Fetal brain cells of gestational age of 16 weeks that were frozen in liquid nitrogen were obtained, resuscitated and incubated in DMEM/F12 medium containing epithium growth factor (EGF), basic fibroblast growth factor (bFGF), B27 and N2. The neurospheres cultured for 14 days were obtained. CSF was absorbed from the subarachnoid cavity and brain ventricle in the embryonic group. CSF was collected by lumbar puncture or ventricular puncture in the child group. The neurospheres cultured for 14 days were transplanted into the pure CSF in an incubator containing 5% CO_2 at 37 ℃. Cellular migration and growth of neurospheres in CSF were observed. Effects of CSF on neural cell differentiation were identified by immunofluorescence. RESULTS: Neural stem cells in the form of neurospheres derived from fetal brain were inoculated into the pure CSF, and cell migration were commonly observed besides few of neurospheres in child CSF culture at 6 hours following culture. Surrounding cells of neurospheres extended processes, forming cell cord that became cell webs after extension. Compared with the embryonic group, positive rate of glial fibrillary acidic protein was significantly increased in the children group (P < 0.01), but positive rates of nerve fiber and nestin were significantly decreased (P < 0.01). In addition, galactocerebroside-positive cells were only found in 3 baby CSF cultures. CONCLUSION: There existed significant affections on both migration and differentiation of human neural stem cells when cultured in pure CSF with different developmental phase, suggesting that CSF is one of major niche factors for central neural system development.
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Objective:To investigate the effect of rapamycin eluting coronary stent for inhibition of neointimal hyperplasia in diabetic porcine model.Methods:There were two groups in this study. Diabetic group, n=12, diabetic porcine model was established by a single dose of streptozotocin, and rapamycin eluting coronary stents were randomly implanted into 2 of the major epicardial coronary arteries. Control group, n=12, with non-diabetic porcine. The degree of neointimal hyperplasia evaluated by coronary angiography, intravascular ultrasound (IVUS) and histopathology were compared between two groups respectively at 6 months of the event. Results:The distribution of vessels received stents, reference vessel diameters and post-procedural minimal luminal diameter were comparable between two groups. All animals received angiographic follow-up at 6 months of time. In Diabetic group, the degree of stent stenosis (35.6%±9.2% vs. 7.9%±3.1%,P<0.001), late lumen loss (0.32±0.09 mm vs. 0.09±0.04 mm,P<0.001), the thickness of neointima by IVUS examination (0.35±0.12 mm vs. 0.11±0.08 mm,P<0.05) and area stenosis by IVUS (1.29±0.51 mm~2 vs. 0.26±0.11 mm~2, P<0.001); and histopathological examination (1.24±0.76 mm~2 vs. 0.19±0.08mm~2, P<0.05) were significantly higher than those in Control group. Conclusion: The neointimal hyperplasia after rapamycin eluting stent implantation was significantly severe in the diabetic porcine models than those in non-diabetic ones.