Journal of Alzheimer's Disease - Volume 47, issue 2

Authors: Xie, Yunyan | Cui, Zaixu | Zhang, Zhongmin | Sun, Yu | Sheng, Can | Li, Kuncheng | Gong, Gaolang | Han, Ying | Jia, Jianping

Article Type: Research Article

Abstract: Identifying amnestic mild cognitive impairment (aMCI) is of great clinical importance because aMCI is a putative prodromal stage of Alzheimer’s disease. The present study aimed to explore the feasibility of accurately identifying aMCI with a magnetic resonance imaging (MRI) biomarker. We integrated measures of both gray matter (GM) abnormalities derived from structural MRI and white matter (WM) alterations acquired from diffusion tensor imaging at the voxel level across the entire brain. In particular, multi-modal brain features, including GM volume, WM fractional anisotropy, and mean diffusivity, were extracted from a relatively large sample of 64 Han Chinese aMCI patients and 64 …matched controls. Then, support vector machine classifiers for GM volume, FA, and MD were fused to distinguish the aMCI patients from the controls. The fused classifier was evaluated with the leave-one-out and the 10-fold cross-validations, and the classifier had an accuracy of 83.59% and an area under the curve of 0.862. The most discriminative regions of GM were mainly located in the medial temporal lobe, temporal lobe, precuneus, cingulate gyrus, parietal lobe, and frontal lobe, whereas the most discriminative regions of WM were mainly located in the corpus callosum, cingulum, corona radiata, frontal lobe, and parietal lobe. Our findings suggest that aMCI is characterized by a distributed pattern of GM abnormalities and WM alterations that represent discriminative power and reflect relevant pathological changes in the brain, and these changes further highlight the advantage of multi-modal feature integration for identifying aMCI. Show more

Keywords: Alzheimer’s disease, amnestic mild cognitive impairment, classification, diffusion tensor imaging, structural magnetic resonance imaging, support vector machine

DOI: 10.3233/JAD-150184

Citation: Journal of Alzheimer's Disease, vol. 47, no. 2, pp. 509-522, 2015

Authors: Giil, Lasse M. | Kristoffersen, Einar K. | Vedeler, Christian A. | Aarsland, Dag | Nordrehaug, Jan Erik | Winblad, Bengt | Cedazo-Minguez, Angel | Lund, Anders | Reksten, Tove Ragna

Article Type: Research Article

Abstract: Background: Autoantibodies with agonist function are described in cardiovascular disorders. Since vascular risk factors are associated with an increased risk for Alzheimer’s disease (AD), we investigated a potential association between antibodies to the angiotensin 2 type 1 receptor (anti-AT1R) and AD. Objective: The primary objective of this study was to investigate the association between anti-AT1R and AD. The secondary objective was to investigate the association between clinical or biomarker features of AD and anti-AT1R. Methods: Samples from patients with mild AD participating in a longitudinal study in Western Norway (n  = 92, 65 …[71%] females, mean age 74.8 [range 50–89]) and age- and gender-matched healthy controls (n  = 102) were included. Cerebrospinal fluid (CSF) AD biomarkers were assessed in a subgroup of patients. Patients were examined annually, including Mini-Mental State Examination. ELISA was used to measure anti-AT1R in serum. Non-parametric tests were used for statistical calculations and a p  <  0.05 was considered significant. Results: AD patients had significantly higher levels of anti-AT1R compared with healthy controls (10.2 U/mL versus 8.1 U/mL, p  = 0.04). This difference was found only in patients without hypertension and diabetes. Anti-AT1R levels correlated with CSF total tau (p  = 0.03) and phosphorylated tau (p  = 0.03) levels, and inversely with blood pressure in AD (Spearman R −0.277, p  = 0.008). Discussion: AD is associated with increased levels of anti-AT1R, and the antibodies correlated with CSF total, and phosphorylated tau levels. Further research is needed to understand the blood pressure response in AD without hypertension and a potential link between tau and anti-AT1R in AD. Show more

Keywords: AT1R, autoimmunity, dementia, neurodegeneration

DOI: 10.3233/JAD-150053

Citation: Journal of Alzheimer's Disease, vol. 47, no. 2, pp. 523-529, 2015

Article Type: Meeting Report

DOI: 10.3233/JAD-150425

Citation: Journal of Alzheimer's Disease, vol. 47, no. 2, pp. 531-534, 2015