BACKGROUND:As a neurotrophic factor, basic fibroblast growth factors extensively distribute in the central nervoussystem,andplay an important physiological roleby combinationwith their relative receptors.
OBJECTIVE:To investigate the effect of basic fibroblast growth factors on the learning ability and proliferation of nestin-positive hippocampal neural stem cels in rats with vascular dementia.
METHODS:Totaly 30 Sprague-Dawley rats were randomly divided into vascular dementia, sham operation and treatment groups. The vascular dementia and treatment groups were for preparing vascular dementia model, and the treatment group was given subcutaneous injection of basic fibroblast growth factors. Subsequently, at 4 weeks, the learning ability of rats and the number of nestin-positive hippocampal neural stem cels was detected by the Morris water maze test and immunohistochemical staining, respectively.
RESULTS AND CONCLUSION:Compared with thevascular dementia groupthe latency period was significantlyshorterin thesham operation and treatment groups, and the number oftimes crossing the target quadrant was significantlyhigher in thesham operation and treatment groups (P< 0.05). But there was no significant difference between the sham operation and treatment groups(P> 0.05). Under fluorescence microscope, yelow-green fluorescence stained neuronspositive forbasic fibroblast growth factorcould be found in the CA1, CA2 and CA3 of the treatment group. Additionaly, the number of nestin-positive neurons in the CA1 area of the hippocampus was the most inthetreatment group, folowed by the sham operation group, andthe leastin the vascular dementia group. These results suggest that the subcutaneous injection of basic fibroblast growth factors can migrate to the hippocampus,, andimprove the learning ability of rats by inducing proliferation of nestin-positive hippocampal neural stem cels.

Objective:To study the effects of Hedgehog signal transduction pathway on the cell proliferation, apoptosis and connexin 32 (Cx32)and connexin 43 (Cx43)membranous distribution of breast cancer cells,and to explore its mechanism in the cell proliferation and metastasis of breast cancer.Methods:The breast cancer MCF-7 cells at logarithmic growth period were divided into cyclopamine groups and blank control groups. The MCF-7 in cyclopamine groups were treated with 5,10,20,30 and 40μmol·L-1 for 24,48 and 72 h;MTT assay was applied to detect the inhibitory rate of proliferation of MCF-7 cells. After the MCF-7 cells were treated with 0 (negative control group)and 25μmol·L-1 cyclopamine for 48 h,flow cytometry was employed to determine the apoptotic rate and to analyze membranous distribution of Cx32 and Cx43 in the MCF-7 cells.Results:Compared with blank control group,the inhibitory rates of proliferation in cyclopamine groups were increased (P<0.05), and the inhibitory effect of proliferation was increased with the increasing of cyclopamine doses and prolongation of treatment time.After treated with 25μmol·L-1 cyclopamine,the apoptotic rate of MCF-7 cells was higher than that in blank control group (P<0.05).The positive expression rates of Cx32 and Cx43 48 h after treatment were higher than those in negative control group (P<0.05).Conclusion:Hedgehog signal transduction pathway can inhibit the apoptosis and mediate membranous distribution of Cx32 and Cx43 in breast cancer cells.

Objective:To prepare PLGA nanoparticles modified with folic acid conjugated chitosan oligosaccharide containing pa-clitaxel (F-CS-PLGA-NPs) and study the inhibitory effect on SKOV-3. Methods:F-CS-PLGA-NPs were prepared by an interface dep-osition method, 30% ethanol was used as the release medium for the in vitro release profiles of nanoparticles, and MTT was adopted to evaluate the inhibitory effect of paclitaxel with different formulations and concentrations on SKOV-3. Results:The particle size and zeta potential of F-CS-PLGA-NPs was (321 ± 0. 76) nm and (22. 6 ± 0. 26) mV, respectively, the drug loading was (5. 1 ± 0. 25)%, and the encapsulation efficiency was (41. 96 ± 1. 96)%. F-CS-PLGA-NPs had a similar in vitro release profiles with the ordinary nanoparti-cles ( PLGA-NPs) . About 35% of paclitaxel was released from the nanoparticles in the initial 24 h, and then a near zero order release at a relative slow rate was shown, and the cumulative release rate in 144 h was about 75%. The results of cell experiments suggested that at the same paclitaxel concentration, the inhibition effect of F-CS-PLGA-NPs group was stronger than that of the PLGA-NPs group and the solution group. The inhibition effect of F-CS-PLGA-NPs could be reduced by free folic acid. Conclusion:PLGA nanoparticles modified with folic acid conjugated chitosan oligosaccharide can increase the targeting efficiency in SKOVS-3 tumor cells.