RESUMO
BACKGROUND: Studies have demonstrated that platelet-rich plasma can promote osteogenesis and proliferation of bone marrow mesenchymal stem cells, adipose-derived stem cells and skeletal muscle satellite cell, but whether it can promote the proliferation and osteogenesis of human umbilical cord mesenchymal stem cells (hUC-MSCs) is unclear. OBJECTIVE: To investigate the effects of different concentrations of platelet-rich plasma on the proliferation and osteogenic differentiation of hUC-MSCs. METHODS: Passage 5 hUC-MSCs were cultured in medium containing different concentrations of platelet-rich plasma (0, 250, 500, 750, 1000, 2000 ng/L), respectively. Cell proliferation was detected at 1, 3, 5, 7 days after culture, and the best platelet-rich plasma mass concentration was screened. Afterwards, passage 5 hUC-MSCs were divided and cultured in complete medium (blank control group), optimal concentration of platelet-rich plasma (platelet rich plasma group), osteogenesis induction medium (osteogenic induction group), or the osteogenesis induction medium containing the optimal concentration of platelet-rich plasma (combined group). Cell activity of alkaline phosphatase was detected after cultivated for 3, 7, 14 days. Osteopontin, bone specific transcription factor, and osteocalcin mRNA relative expression levels were detected after cultivated for 7, 14, 21 days. Mineralization of the extracellular matrix was detected after cultivated for 21 days. RESULTS AND CONCLUSION: After 5 and 7 days of culture, the cell proliferation was higher in 500, 750, 1000 ng/L platelet-rich plasma groups than 0 ng/L group (P < 0.05), and 750 ng/L platelet-rich plasma showed the best effect on cell proliferation, which was used in the following experiments. Compared with the other groups, the combined group had significantly increased alkaline phosphatase activity (P < 0.05), and up-regulated osteopontin, bone specific transcription factor and osteocalcin mRNA relative expression levels (P < 0.05) at different culture times. In addition, the degree of extracellular matrix mineralization in the combined group was also higher than that in the other three groups (P < 0.05).To conclude, 750 ng/L platelet-rich plasma can promote hUC-MSCs proliferation and osteogenic differentiation.
RESUMO
BACKGROUND:Neural stem cel transplantation provides an important way to treat sequela of traumatic brain injury, but the timing for treatment is inconclusive. OBJECTIVE:To explore the clinical effect of neural stem cel transplantation in the treatment of sequela of traumatic brain injury and the choice of the best treatment time. METHODS: Totaly 178 patients with sequela of traumatic brain injury who underwent neural stem cel transplantation were divided into three groups as per the timing for neural stem cel transplantation: group A (with 6 months after injury,n=60), group B (6-12 months after injury,n=59), and group C (over 12 months after injury,n=59). Improvement in clinical symptoms and scores on function independent measure (FIM) were recorded and compared in the three groups. RESULTS AND CONCLUSION:The total effective rate of group A was significantly higher than that in groups B and C (P < 0.05). FIM scores were significantly improved in the three groups after cel transplantation (P < 0.05). At 3 months after the fourth transplantation, the FIM score in the group A was significantly higher than that in the other two groups, and the incidence of adverse reactions in the group A was significantly lower than that in the other two groups (P < 0.05). These findings indicate that neural stem cel transplantation at different timing can al harvest certain clinical effects, but the best timing for neural stem cel transplantation is within 6 months after injury.