RESUMO
BACKGROUND: Human umbilical cord blood mesenchymal stem cells (hUC-MSCs) can repair the injury of nerve cells caused by ischemia and hypoxia, but which state of cells has a better therapeutic efficacy, primary isolation or induced differentiation is not yet known. OBJECTIVE: To compare the therapeutic effects of hUC-MSCs primary cultured and differentiated in a rat model of cerebral infarction.METHODS: After full-term delivery, fetal umbilical cord blood samples were obtained using quadruple bags by means of density gradient centrifugation. hUC-MSCS were induced in the medium containing basic fibroblast growth factor. Sixty rats were equivalently randomized into four groups: sham, model, primary culture and induced differentiation groups. Animal models of cerebral infarction were made in the rats in the latter three groups. Model rats in the primary culture and induced differentiation groups were subjected to tail vein transplantation of hUC-MSCs that were primary cultured or induced to differentiate in vitro at 7 days after modeling. RESULTS AND CONCLUSION: A marked improvement in balance, walking, spatial orientation, and learning and memory abilities was found in the rats after transplantation of hUC-MSCs that were primary cultured or induced to differentiate. Moreover, compared with the primary culture group, a significant improvement was found in the induced differentiation group, including improved pathological injury of the brain, higher expression of CD34 and Ki-67, lower expression of glial fibrillary acidic protein, lower expression of interleukin 1β and tumor necrosis factor β. Compared with the primary culture group, similar infarction size and expression of interleukin-6 were also found in the induced differentiation group. These findings indicate that hUC-MSCs with induced differentiation exhibit better therapeutic outcomes in the recovery of neurological function of cerebral infarction rats.
RESUMO
This study was purposed to investigate the effects of 25 Gy gamma-ray irradiation on the CD62p expression, platelet count and the mean platelet volume (MPV) of manually enriched platelet suspension in different time of shelf life at 22 degrees C. Each of 16 bags with plasma-rich platelet was divided into two bags, one of which was exposed to 25 Gy gamma-ray of 137Cs and the other ones was not exposed. 16 bags then were preserved for 72 hours according to AABB standards. The irradiated platelets were regarded as the observation group, and the other ones were regarded as the control group, the expression of p-selectin (CD62p) in the above 2 groups was detected by flow cytometry before irradiation and at 24, 72 hours after irradiation respectively; at the same time, the platelet count and MPV were assayed by using blood cell counter. The results showed that the expression level of CD62p on platelet in irradiated and control groups increased along with the prolonging of preservation time, the expression rate of CD62p on the platelets preserved for 24 hours was higher than that on fresh platelets with significant difference (p<0.05); the expression rate of CD62p on the platelets preserved for 72 hours obviously was enhanced as compared with platelets preserved for 24 hours (p<0.01). There were no significant differences in CD62p expression rate, platelet count and MPV between irradiated and control groups preserved for 24 and 72 hours (p>0.05), however the MPV of irradiated and control groups preserved for 72 hours was higher than that of fresh platelets (p<0.05). It is concluded that the gamma-ray irradiation does not affect the quantity and quality of platelets, but the preservation time for manually enriched platelet suspension should be shortened as far as possible.