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The massive loss of oligodendrocytes caused by various pathological factors is a basic feature of many demyelinating diseases of the central nervous system (CNS). Based on a variety of studies, it is now well established that impairment of oligodendrocyte precursor cells (OPCs) to differentiate and remyelinate axons is a vital event in the failed treatment of demyelinating diseases. Recent evidence suggests that Foxg1 is essential for the proliferation of certain precursors and inhibits premature neurogenesis during brain development. To date, very little attention has been paid to the role of Foxg1 in the proliferation and differentiation of OPCs in demyelinating diseases of the CNS. Here, for the first time, we examined the effects of Foxg1 on demyelination and remyelination in the brain using a cuprizone (CPZ)-induced mouse model. In this work, 7-week-old Foxg1 conditional knockout and wild-type (WT) mice were fed a diet containing 0.2% CPZ w/w for 5 weeks, after which CPZ was withdrawn to enable remyelination. Our results demonstrated that, compared with WT mice, Foxg1-knockout mice exhibited not only alleviated demyelination but also accelerated remyelination of the demyelinated corpus callosum. Furthermore, we found that Foxg1 knockout decreased the proliferation of OPCs and accelerated their differentiation into mature oligodendrocytes both in vivo and in vitro. Wnt signaling plays a critical role in development and in a variety of diseases. GSK-3β, a key regulatory kinase in the Wnt pathway, regulates the ability of β-catenin to enter nuclei, where it activates the expression of Wnt target genes. We then used SB216763, a selective inhibitor of GSK-3β activity, to further demonstrate the regulatory mechanism by which Foxg1 affects OPCs in vitro. The results showed that SB216763 clearly inhibited the expression of GSK-3β, which abolished the effect of the proliferation and differentiation of OPCs caused by the knockdown of Foxg1. These results suggest that Foxg1 is involved in the proliferation and differentiation of OPCs through the Wnt signaling pathway. The present experimental results are some of the first to suggest that Foxg1 is a new therapeutic target for the treatment of demyelinating diseases of the CNS.
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Objective To evaluate the safety and effectiveness of repeated transcranial magnetic stimulation ( rTMS) for treating non-fluent aphasia after stroke. Methods Forty-five stroke survivors with non-fluent aphasia were randomly divided into a 0.5 Hz group, a 1 Hz group and a sham group, each of 15. In addition to routine lin-guistic training, the three groups were given rTMS over the inferior frontal gyrus of the right hemisphere at the corre-sponding frequency or sham stimulation. Before as well as 5 and 10 days after the treatment, all of the subjects were evaluated using the Chinese version of the Western Aphasia Battery ( WAB) . The occurrence of adverse events was al-so observed. Results Before treatment, no significant differences were observed in the groups' average aphasia rati-o, spontaneous speech, listening comprehension, retelling and naming using the WAB. After 5 and 10 days signifi-cant increases were observed in the average WAB scores of all three groups, but the listening comprehension of the 0.5 Hz group was significantly better than that of the sham group 10 days later, as was the spontaneous speech of the 1 Hz group. Conclusion rTMS at either 1 Hz or 0.5 Hz can improve the linguistic functioning of stroke survivors with non-fluent aphasia. Both 0.5 Hz and 1 Hz rTMS are safe, but the latter is more effective.
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Objective@#To evaluate the safety and effectiveness of repeated transcranial magnetic stimulation (rTMS) for treating non-fluent aphasia after stroke.@*Methods@#Forty-five stroke survivors with non-fluent aphasia were randomly divided into a 0.5 Hz group, a 1 Hz group and a sham group, each of 15. In addition to routine linguistic training, the three groups were given rTMS over the inferior frontal gyrus of the right hemisphere at the corresponding frequency or sham stimulation. Before as well as 5 and 10 days after the treatment, all of the subjects were evaluated using the Chinese version of the Western Aphasia Battery (WAB). The occurrence of adverse events was also observed.@*Results@#Before treatment, no significant differences were observed in the groups′ average aphasia ratio, spontaneous speech, listening comprehension, retelling and naming using the WAB. After 5 and 10 days significant increases were observed in the average WAB scores of all three groups, but the listening comprehension of the 0.5 Hz group was significantly better than that of the sham group 10 days later, as was the spontaneous speech of the 1 Hz group.@*Conclusion@#rTMS at either 1 Hz or 0.5 Hz can improve the linguistic functioning of stroke survivors with non-fluent aphasia. Both 0.5 Hz and 1 Hz rTMS are safe, but the latter is more effective.
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The study was o investigate the effectiveness of problem-based learning and scenario simulated teaching in Pathological experiment course.Clinical common,multiple cardiovascular diseases related experiments were selected for reform.The case was in advance handed out to the second year students of clinical medicine,stomatology,imaging medicine and otherspecialty,requiring them to complete the data access,group discussion,PPT production,diagnoses and treatment scenarios simulation video shooting tasks.Every group showed their PPT and video in class.They were asked between groups.Summative evaluation was given before class.Curriculum effectiveness questionnaire was issued and recycled,and according to students' performance teacher gave their scores and reward.The study showed that the comprehensive application of the above teaching methods and means could effectively improve students' learning enthusiasm and initiative,cultivate their medical humanistic spirit,and help to improve the teaching quality of pathology experiment.
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BACKGROUND: Researches find that grape seed proanthocyanidins (GSP) can eliminate free radicals, protect heart against ischemia-reperfusion injury and enhance learning and memory abilities in experimental animal, but their effects on the cerebral ischemia-reperfusion injury remain unclear.OBJECTIVE: To study the protective effects of proanthocyanidins derived from grape seeds on the cerebral ischemic reperfused brain by measuring the total antioxidative capacity (T-AOC), nitric oxide synthase activities and malondialdehyde (MDA) content in brain tissue of mice.DESIGN: A completely randomized and controlled study.SETTING: Department of Pathophysiology and Functional Central Laboratory, Jinzhou Medical College; Department of Neurology, the First Affiliated Hospital of Jinzhou Medical College.MATERIALS: The experiment was conducted in the Department of Functional Central Laboratory, Jinzhou Medical College from March to August 2004. Forty Kunming mice, provided by the Experimental Animal Center, Jinzhou Medical College, were randomly divided into five groups: sham control group, cerebral ischemia-reperfusion group (IR group) and cerebral ischemia-reperfusion treated with low or high dose of GSP or nimdipine (IR+GSP or IR+Nim) group with eight mice in each group.METHODS: ① Animal model establishment: The animals were anesthetized with ether. Then they were incised through median incision of the neck. The bilateral common carotid arteries were then occluded by microaneurysm clips for 30 minutes. After removing the clips, return of flow was visualized in the arteries. ② Model group and control group:The mice in low or high dose of GSP treated group or nimdipine treated group were injected GSP or nimdipine 10, 40, 2 mg/kg body mass respectively during the common carotid arteries occlusion and again at 24hours after reperfusion, while the mice in sham control group were injected the same volume distilled water with 40 mg/kg body mass. After 72-hour reperfusion, nitric oxide synthase activities, the total antioxidative capacity and MDA content in brain tissue of mice in each group were detected with chemical chromatometry. ③ The results were assessed by t test.MAIN OUTCOME MEASURES: Nitric oxide synthase activities, the total antioxidative capacity and MDA content in brain tissue of mice in each group were detected.RESULTS: Data of forty Kunming mice was entered the results analysis without any loss. ① Total antioxidative capacity: Total antioxidative capacity in cerebral ischemia-reperfusion group was obvious lower than that in the sham control group (t=8.145, P=0.000) while total antioxidative capacity in low or high dose of GSP treated group and nimdipine treated group was obvious higher than that in the cerebral ischemia-reperfusion group (t=6.313, 8.956, 4.14, P ＜ 0.01). ② Nitric oxide synthase activities: Nitric oxide synthase activities in cerebral ischemia-reperfusion group was obvious higherthan that in the sham control group (t=12.541, P ＜ 0.01), while nitric oxide synthase activities in low or high dose of GSP treated group and nimdipine treated group was obvious lower than that in the cerebral ischemia-reperfusion group (t=2.231, 8.956, 7.260, P ＜ 0.05-0.01). ③ MDA content: MDA content in cerebral ischemia-reperfusion group was obvious higher than that in the sham control group (t=7.883, P ＜ 0.01), while high dose of GSP treated group and nimdipine treated group was obvious lower than that in the cerebral ischemia-reperfusion group (t =5.234,4.518, P ＜ 0.01).CONCLUSION: GSP exerted a protective effect on the cerebral ischemic reperfused brain by enhancing total antioxidative capacity and reducing lipid peroxidantion and nitric oxide synthase activities.
