ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Amyloid precursor protein (APP) gene encodes the short peptide fragment amyloid-beta-protein present in senile plaque cores, cerebrovascular amyloid, and intracellular neurofibrillary tangles in Alzheimer disease (AD). Usingin situhybridization with biotin-labeled RNA probes, we found distinctive patterns of APP gene expression in different regions of postmortem human brain. Strong hybridization signal for APP messenger RNA (mRNA) was detected in specific classes of neurons, fascicular oligodendroglia, satellite glia, and presumptive microglia. Weaker signal was seen in other neuronal classes, fascicular astrocytes, and vascular endothelial cells, but no signal was seen in protoplasmic astrocytes. Human thymus also shows a restricted pattern of hybridization with high signal in reticular epithelial cells, and much lower signal in lymphocytes. In AD patients, neuronal hybridization for APP mRNA was specifically increased in hippocampus, but not cerebellar and visual cortex when compared to hybridization for neuron-specific enolase mRNA. Most neurons with neurofibrillary tangles had strong APP mRNA signal. These results suggest that APP gene expression is highly regulated in normal tissue, that many different cell classes in brain express the APP gene, and that neuronal expression may increase specifically in brain regions where widespread injury occurs in AD. Amyloid deposits in brains of AD patients might be explained by local production of precursor protein in endothelial cells, neurons or glia.

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Patients with Alzheimer disease (AD) invariably display pronounced deficits in verbal memory when retention is tested explicitly. The present study examined the possibility that tasks which require memory only implicitly would be performed normally. Moderately demented patients with probable AD were severely impaired in free recall of a word list. On a subsequent word association test, the AD patients were less likely than normals to give items from the recall list as their word associations. The results suggest that implicit verbal memory, as well as explicit memory, is impaired in AD. While the magnitude of the activation effect was significantly reduced in AD patients, it was uncorrelated with recall performance or a measure of global cognitive functioning. Memory activation may thus depend on neural circuitry outside the traditional (i.e. temporo-limbic) memory system.

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Flow cytometry studies to measure mean DNA content and intercellular variability around the mean were performed on mononuclear blood cells obtained from 21 patients with a clinical diagnosis of dementia of the Alzheimer type (DAT) and 25 cognitively intact individuals. There was no difference in the mean DNA content between both groups. However, patients with DAT had significantly increased intercellular variability compared to controls (3.52 vs. 3.06, respectively). These results are consistent with the reports of increased aneuploidy associated with DAT found on cytogenetic examination.

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID

ISSN:0893-0341    

出版商:OVID    

年代:1988

数据来源: OVID