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Objective To investigate the expressions of protein kinase B (PKB/Akt) and glycogen synthase kinasc-3β in the hippocampus in mice with vascular dementia (VaD) induced by repetitive bilateral common carotid artery occlusion.Methods Forty-eight healthy adult male C57B1/6 mice were randomly allocated into 3 group:normal group,sham operation group,and model group (n =16 in each group).A mouse VaD model was induced by intermittent blocking the bilateral common carotid artery for 3 times in the model group.The sham group only separated the bilateral common carotid artery,but did not block it.The normal group did not receive any treatment.The behavioral changes of the mice were observed using the water maze and step-down tests at 4 weeks after procedure.HE staining was used to observe the histopathological changes of hippocampal tissue.The Western blotting was used to detect the expressions of Akt,p-Akt (Ser473),GSK3β and p-GSK3β (Ser9) proteins.Results In the water maze test,the time of swimming the entire distance was prolonged at the learning stage and memory stage (learning stage:F =19.389,P ＜0.05; memory stage:F =27.929,P ＜ 0.05),the number of errors increased (learning stage:F =7.228,P ＜ 0.05; memory stage:F =21.189,P＜0.05) in the model group.In the step-down test,the response time was prolonged (F=19.162,P ＜0.05) at learning stage and the number of errors increased (F =6.562,P ＜ 0.05),the latency time was shortened (F=10.634,P＜0.05) and the number of errors increased (F=12.890,P＜0.05) in the model group.At the same time,HE staining showed the reduction of neurons and the proliferation of glial cells in the hippocampal CA1 region in the model group; p-Akt (Ser473) (F=37.849,P＜0.05) and p-GSK3β (Ser9)(F =67.725,P ＜0.05) protein expressions were up-regulated significantly (F =37.849,P ＜0.05; F =67.725,P＜0.05) at 4 weeks after procedure compared to those in the sham operation group,while there were no significant differences in Akt (F =1.004,P ＞0.05) and GSK3β(F =0.329,P ＞0.05) total protein expressions among all groups.Conclusions The repetitive bilateral common carotid artery occlusion may result in learning and memory impairment and severe damage in the hippocampus in mice.The Akt and GSK3β expressions may be involved in the mechanism of VaD.
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Objective To investigate the histochemical characteristics of muscle fiber in patients with Becker type muscular dystrophy (BMD) and its clinical significance.Methods Muscular biopsies were performed in 3 patients with BMD. The specimens were stained by HE and nicotinamide-adenine dinucleotid-tetrazole reducase (NADH-TR) methods and observed under light microscope. Normal muscles from healthy people were saved as controls.Results The slice from BMD patients showed varied sizes of muscular fibers, remarkable hypertrophy fibers, splitting fibers, targetoid fibers, lobulated fibers, whorled fibers and ring fibers. Targetoid fibers were also found using NADH-TR staining.Conclusions The degree of fiber necrosis in BMD is mild. Degeneration and proliferation are the main pathological changes, which predict mild clinical symptoms, long course of disease and favourable prognosis.