Neurobiology of aging
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Neurobiology of aging · Apr 2005
Comparative StudyWhite matter lesions are associated with cortical atrophy more than entorhinal and hippocampal atrophy.
The goal of this study was to examine the relationship between subcortical vascular disease and brain atrophy in patients with Alzheimer's disease (AD) and mixed dementia (i.e., AD and subcortical vascular disease together). MRI was performed on 77 cognitively normal (CN) subjects, 50 AD and 13 mixed dementia patients. Subcortical vascular disease was determined by white matter hyperintensities (WMH) volume and presence of subcortical lacunes. ⋯ Furthermore, no interaction was found between WMH and diagnosis on cortical atrophy, implying that WMH affect cortical atrophy indifferently of group. These results suggest that subcortical vascular disease, manifested as WMH, may affect cortical atrophy more than ERC and hippocampal atrophy. Further, AD pathology and subcortical vascular disease may independently affect cortical atrophy.
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Neurobiology of aging · Apr 2005
Comparative StudyVascular risk factors and cognitive function in a sample of independently living men.
Decline of cognitive function with age may be due, in part, to atherosclerotic changes. The aim of the present study was to determine the relative contribution of vascular risk factors to cognitive functioning in a non-clinical sample of men. Cognitive tests were administered to 400 independently living men aged 40-80 years. ⋯ Hierarchical regression analyses revealed independent contributions of the combination of vascular risk factors in explaining the observed variance in performance on tests of cognitive functioning targeted at information processing capacity and speed and general cognitive status. Of the individual predictor variables, alcohol intake and homocysteine levels were significantly associated with processing capacity and speed, and peak expiratory flow rate was significantly associated with general cognitive status. Our results indicate that the combination of several independent vascular risk factors predicts performance on cognitive tests of information processing capacity and speed in a population-based sample of middle-aged and elderly men.
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Neurobiology of aging · Nov 2003
Clinical Trial Controlled Clinical TrialIncreased concentrations of homocysteine and asymmetric dimethylarginine and decreased concentrations of nitric oxide in the plasma of patients with Alzheimer's disease.
Vascular risk factors increase the risk of developing Alzheimer's disease. Increased concentrations of circulating homocysteine are associated with an increased risk of both vascular disease and Alzheimer's disease. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase. ⋯ Endothelial dysfunction is also associated with atherosclerosis and stroke, which are important risk factors for Alzheimer's disease. Inflammation plays an important role in Alzheimer's disease and the inhibition of endothelial nitric oxide by ADMA may increase the concentration of inflammatory mediators in the brain. The inhibition of neuronal nitric oxide synthesis by ADMA may cause cognitive dysfunction in Alzheimer's disease.
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Neurobiology of aging · Jan 2003
Comparative StudyThe MRI pattern of frontal and temporal brain atrophy in fronto-temporal dementia.
To compare patterns of brain atrophy in fronto-temporal dementia (FTD) and Alzheimer's disease (AD) since atrophy in individual areas may not be sufficiently specific as diagnostic marker. ⋯ FTD is characterized by a specific pattern of atrophy, more useful than atrophy of single regions in the differential diagnosis.