ABSTRACT
Objective To investigate platelet α and β secretase activities and the amounts of platelet soluble fragment of APP (sAPPα) produced by α-secretase in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD).Methods The neurological functions of 48 nondemented patients,42 MCI and 40 AD patients were evaluated by neuropsychological examinations.The platelet α and β secretase activities and sAPPα production in each group were measured by fluorescence and Western blotting analysis respectively.Results The α secretase activities in non-demented,MCI and AD group were 100.0％ ± 10.6％,78.2％ ± 9.4％ and 61.8％ ± 7.2％ respectively.As compared with nondemented group,the α secretase activities in MCI and AD group were decreased (F =22.935,P =0.001).The α secretase activity in AD group was significantly lower than MCI group.The β secretase activities in non-demented,MCI and AD group were 100.0％ ± 11.2％,145.8％ ± 12.7％ and 189.8％ ± 14.2％respectively.The β secretase activities in MCI and AD group were significantly higher than that in nondemented group (F =16.368,P =0.001).The β secretase activity in AD group was significantly decreased as compared with MCI group.The sAPPα amounts in MCI group and AD group were all decreased as compared with that in control group; the sAPPo amount in AD patients was significantly decreased as compared with that in MCI group.Conclusions The platelet α secretase activity and its production sAPPα in MCI and AD patients are decreased,while β secretase activity is increased,as compared with that in control group; the altered α and β secretase activities may participate in the pathogenesis of MCI and AD patients and may have diagnostic potential for them.
ABSTRACT
The cluster sampling method was used and a retrospective survey on mortality trends of cerebrovascular diseases from 1989 to 2008 was conducted among residents from Erqi District in Zhengzhou city and Xigong District in Luoyang city. The average mortality rate of cerebrovascular diseases in these two districts was 69. 5/100 000 in 1989 to 2008. The standardized mortality rate for men was 118. 67/100 000 in 1989 to 1993, and dropped to 44. 23/100 000 in 2004 to 2008. The standardized mortality rate for women was 68.21/100 000 in 1989 to 1993, and dropped to 30. 2/100 000 in 2004 to 2008. The declining trends of cerebrovascular disease mortality rates might be related to early diagnosis and early treatment of the disease, and the extensive health education and prevention programs.