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Objective:To study the effects of IL 6、IL 1? and TNF? on the expression of c fos and c jun,which may provide the foundation for a further study in clinic.Methods:Used the a model of primary culture of human fetal cerebral neurons in serum free medium,by DNA RNA dot blot hybrdization.Results:The expression of c fos and c jun was increased between 15 min to 30 min after stimulation,reached a maximum at 1 h and declined over the subsequent 1 h.Conclusion:IL 6、IL 1? and TNF ? have induce the expression of c fos and c jun during development of human fetal cerebral neurons in vitro at the level of transcription.
RESUMO
The thyroid allografts in rats were cultured for 48h in the conditions of hyperbaric oxygen (a mixture of 95% O2,5% CO2 pressurized at 2 atmospheres)and low pH(5.5 and 6.9).Uncultured and air cultured allografts were taken as control groups.The thyroid slices were transplanted under the kidney eapsulse of thyroidectomized recipients.By examining histological changes,detecting the serum T3 and T4 levels and five weeks body weight gain,the graft survival was cvaluated.Though the thyroids cultured in hyperbaric O2 were contaminated with the passenger leukocytes,the grafts had prolonged survival,suggesting this method might effectively diminish MHC immunogenicity to thyroid grafts.
RESUMO
Objective The aim of the study was to assess the human neural stem cells (NSCs) induced by mitogens in vitro and investigate effects of TH(T 3) on differentiation. Methods The cerebral hemispheres of human fetal at 10-12 weeks of gestation were minced and mechanically dissociated. Cells were seeded at a concentration of 10 5 per ml into defined medium that consisted of DMEM/F12 Epidermal growth factor (EGF,20??g/L) and basic fibroblast growth factor (bFGF,20??g/L) were added respectively as mitogens for 7 days. In some cases, triiodothyronine (T 3, 30??g/L) was added through the culture period. Upon differentiation, the cell cultures were exposured to a substrate and treated with or without T 3 after removing the mitogens. To detect the phenotypes of differentiated cells, immunochemistry staining was performed with the antibody to NF 200, GFAP, MBP and Gal C. To recognize the different stages of oligodendrocytes development, the antibodies O4 and A2B5 were used. The proportion of each neural cell type was determined by counting positive cells in standardized fields at 40? magnifications. Results NSCs induced by EGF and/or bFGF grew in culture as free floating spheres(neurospheres) and were immunoreactive for the intermediate filament nestin. After removing EGF and bFGF, the cells cease mitosis and can be induced to differentiate into neurons, astrocytes, and oligodendrocytes regardless of whether T 3 was presented. T 3 favored an neuroglia cell fate especially when combining EGF with T 3 and differentiated cells appeared more early when added of T 3.MBP positive cell is over 80%. The O4 and A2B5 positive cells can be observed at early stage of differentiation only after process grew from neurospheres after adhesion to certain substrate, which indicated that the neuronal network could promote the maturity of oligodendrocyte.Discussion The timing of NSCs differentiation depends on both intracellular mechanisms and extracellular signals. TH is such a signal to activate the effector component of a “clock” mechanism that induces oligodendrocyte differentiation after a limited number of cell divisions.[