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AD Subjects (ad + subject)
Selected AbstractsEvent-related delta oscillatory responses of Alzheimer patientsEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2008G. Yener Background and purpose:, Alzheimer type of dementia (AD) is the most common neuropsychiatric morbidity in elderly individuals. Event-related oscillations (ERO) provide an useful tool for detecting subtle abnormalities of cognitive processes with high temporal resolution. Methods:, In the present report, event-related oscillations of patients with AD were analyzed by using a visual oddball paradigm. A total of 22 mild probable AD subjects according to NINCDS-ADRDA criteria and 20 age-, gender-, and education-matched healthy control subjects were compared. AD group consisted from 11 untreated patients and 11 patients treated with cholinesterase inhibitor. Oscillatory responses were recorded from 13 scalp electrodes. Results:, Significant differences in delta frequency range were seen between the groups by using repeated measures of anova analysis [F(9.120) = 2.228; P = 0.022]. Post-hoc analyses using Wilcoxon test showed that at mid- and left central regions, (Cz, C3) peak amplitudes of delta responses of healthy subjects were significantly higher than either group. Also cholinesterase inhibitors did not have effect on delta oscillatory responses. Conclusions:, Our findings imply that the delta oscillatory responses at central locations are highly instable in mild probable AD patients regardless of treatment when compared to the healthy aged controls. This study supports the importance of oscillatory event-related potentials for investigating AD brain dynamics. [source] Working memory in early Alzheimer's disease: a neuropsychological reviewINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2010J. D. Huntley Abstract Background Reports of the extent of working memory (WM) impairment in early Alzheimer's disease (AD) have been inconsistent. Using the model of WM proposed by Baddeley, neuropsychological evidence for the impairment of WM in early AD is evaluated. Method Literature searches were performed using Medline, PsycINFO and Embase databases. Individual papers were then examined for additional references not revealed by computerised searches. Results Phonological loop function is intact at the preclinical and early stages of AD, becoming more impaired as the disease progresses. In mild AD, there is impairment on tasks assessing visuospatial sketchpad (VSS) function; however, these tasks also require executive processing by the central executive system (CES). There is evidence that the CES is impaired in mild AD and may be affected in the earlier preclinical stage of the disease. Episodic buffer function may be impaired but further research is required. Conclusions Future research into central executive functioning at the earliest stages of the disease, combined with further longitudinal studies, needs to be carried out. Tasks to assess the proposed functions of the episodic buffer and specific tests of the VSS suitable for AD subjects need to be developed and validated. Learning more about these processes and how they are affected in AD is important in understanding and managing the cognitive deficits seen in the early stages of AD. Copyright © 2009 John Wiley & Sons, Ltd. [source] A SPECT study of wandering behavior in Alzheimer's diseaseINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2005Yves Rolland Abstract Background Among behavior disturbance during Alzheimer's disease (AD), wandering is one of the most common. Different psychological processes have been suggested to explain the wandering behavior. The aim of this study was to examine whether wandering during AD was associated with cerebral perfusion patterns measured by (99,m)Tc-labeled bicisate (ECD) brain SPECT. Methods We compared SPECT scans of 13 AD subjects with wandering behavior (sex ratio M/F, 4/9; age, 73.1 years, SD 7.4; Mini Mental Status Examination score, median 20 interquartile range [16,23]), 13 AD subjects without wandering behavior (matched for age [,±,2 years], sex and MMSE score [,±,2 points]) and 13 healthy controls (matched for age [,±,2 years] and sex) without cognitive impairment. Wandering was defined on the Neuro-Psychiatric Inventory. Score of leukoaraiosis, assessed with the scale of Blennow and number of lacuna infarction were compared on CT scan. SPECT imaging was compared using statistical parametric mapping (SPM 2). Results There were no significant differences between the groups in term of educational level and CT scan analysis. SPECT imaging was consistent with the diagnosis of AD in both wanderers and AD subjects without wandering behavior. Despite similar clinical dementia severity, wanderers had more severely reduced regional cerebral blood flow (rCBF) in the left parietal-temporal lobe than AD subjects without wandering behavior. Conclusion Wandering behavior could be facilitated by a specific patterns of cerebral blood flow. Wandering, as a physical activity, could also enhance the recruitment of the cortical network. Copyright © 2005 John Wiley & Sons, Ltd. [source] Visuospatial impairment in dementia with Lewy bodies and Alzheimer's disease: a process analysis approachINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 5 2003Martine Simard Abstract Background Reports of differential impairments on visual-construction tasks in dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) are sometimes controversial, whereas visual-perceptual data are lacking. The existence of different clinical sub-groups of DLB has been hypothesized to explain the discrepancies among the cognitive results. The goal of this study was to compare the visual-perceptual performance of subjects with DLB with predominant psychosis, DLB with predominant parkinsonian features and AD. Methods This is a cross-sectional neuropsychological study with between diagnostic group comparisons. The Benton Judgement Line Orientation (BJLO) test was administered to four DLB patients with predominant psychosis (DLB-psy), four DLB subjects with predominant parkinsonian features (DLB-PD), and 13 patients with AD. An analysis of error types was applied to the results of the BJLO with QO1, QO2, QO3, QO4 (visual attention) errors, as well as VH, IQO, IQOV, and IQOH (visual-spatial perception) errors. Results A MANOVA showed significant differences between the DLB, and AD groups on the number of VH (F,=,6.049, df,=,1,19, p,=,0.024), IQOH (F,=,4.645, df,=,1,19, p,=,0.044) and QO1 (F,=,4.491, df,=,1,19, p,=,0.047) errors, but no difference on the total score of the BJLO. Another MANOVA and post hoc Student,Newman,Keuls analyses demonstrated that the DLB-psy sub-group made significantly more VH and IQOH errors than AD and the DLB-PD subjects. Conclusions Subjects with DLB and psychosis have more severe visual-perception (VH errors) impairments than subjects with DLB and predominant parkinsonian features, and AD subjects. Copyright © 2003 John Wiley & Sons, Ltd. [source] The Apathy Inventory: assessment of apathy and awareness in Alzheimer's disease, Parkinson's disease and mild cognitive impairmentINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2002P. H. Robert Abstract Objective This study was designed to establish the validity and reliability of the apathy inventory (IA), a rating scale for global assessment of apathy and separate assessment of emotional blunting, lack of initiative, and lack of interest. Method Information for the IA can be obtained from the patient or from a caregiver. We evaluated 115 subjects using the IA, consisting of 19 healthy elderly subjects, 24 patients with Mild Cognitive Impairment (MCI), 12 subjects with Parkinson's disease (PD) and 60 subjects with Alzheimer's disease (AD). Results Internal consistency, item reliability, and between,rater reliability were high. A test,retest reliability study demonstrated that caregiver responses to IA questions were stable over short intervals. A concurrent validity study showed that the IA assesses apathy as effectively as the Neuro Psychiatric Inventory apathy domain. In the caregiver-based evaluation, AD subjects had significantly higher scores than controls, both for global apathy score and for the lack of interest dimension. When the AD patients were subdivided according to diagnostic criteria for apathy, apathetic patients had significantly higher scores than non apathetic patients. With the patient-based evaluations, no differences were found among the AD, MCI and control groups. The scores in the patient-based evaluations were only higher for the PD group versus the control subjects. The results also indicated that AD patients had poor awareness of their emotional blunting and lack of initiative. Conclusions The IA is a reliable method for assessing in demented and non-demented elderly subjects several dimensions of the apathetic syndrome, and also the subject's awareness of these symptoms. Copyright © 2002 John Wiley & Sons, Ltd. [source] Quantitative analysis of neurofibrillary pathology in a general population to reappraise neuropathological criteria for senile dementia of the neurofibrillary tangle type (tangle-only dementia): The Hisayama studyNEUROPATHOLOGY, Issue 6 2006Kazuhito Noda Senile dementia of the neurofibrillary tangle type (SD-NFT) is characterized by numerous neurofibrillary tangles (NFT) in the hippocampal region and the absence or minimal presence of senile plaques throughout the brain. We analyzed 207 demented subjects and 68 non-demented subjects autopsied in the Hisayama study to investigate the clinicopathological aspects of SD-NFT in the general Japanese population. The prevalence of SD-NFT in the consecutive autopsy cases was 8/207 (3.9%), comprising three men and five women. The average age at onset and death was 83.8 ± 6.8 (mean ± SD; standard deviation) and 88.1 ± 7.6 years, respectively. A mild memory disturbance preceded a decrease in the ability to undertake the activities of daily living and the diagnosis of dementia. Focal cerebral symptoms, such as aphasia and paralysis, did not appear during the disease course of any subject. Gross examination of the brains showed moderate to severe diffuse cerebral atrophy with brain weight loss (mean ± SD; standard deviation: 1118.1 ± 124.0 g). Histologically, there were abundant NFT and neuropil threads predominantly in or limited to the limbic cortex. The density of NFT in the CA1/subiculum in SD-NFT was much higher than the densities in the other hippocampal regions. The average density of NFT in CA1 in SD-NFT subjects was 115.4 per 100× field (range 23,247), that in Alzheimer disease (AD) subjects was 80.1 (range 1,227), and that in non-demented elderly subjects was 37.2 (range 0,203). Although many previous papers have reported that the densities of NFT in the limbic system in SD-NFT were significantly higher than those in AD, there was considerable overlap of NFT densities in CA1 among the non-demented elderly, AD subjects and SD-NFT subjects. [source] The p53 homologue p73 accumulates in the nucleus and localizes to neurites and neurofibrillary tangles in Alzheimer disease brainNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 1 2004C. Wilson The molecular mechanisms that regulate neuronal survival vs. death during Alzheimer disease (AD) remain unclear. Nonetheless, a number of recent studies indicate that increased expression or altered subcellular distribution of numerous cell cycle proteins during AD may contribute to disease pathogenesis. Because homologues of p53, a key regulatory protein in the cell cycle, such as p73, have been identified and shown to participate in cellular differentiation and death pathways, we examined the expression and distribution of p73 in the hippocampus of eight control and 16 AD subjects. In control subjects, hippocampal pyramidal neurones exhibit p73 immunoreactivity that is distributed predominately in the cytoplasm. In AD hippocampus, increased levels of p73 are located in the nucleus of pyramidal neurones and p73 is located in dystrophic neurites and cytoskeletal pathology. Immunoblot analysis confirmed the presence of p73 in the hippocampus. These data indicate that p73 is expressed within hippocampal pyramidal neurones and exhibits altered subcellular distribution in AD. [source] 18F-flutemetamol amyloid imaging in Alzheimer disease and mild cognitive impairment: A phase 2 trialANNALS OF NEUROLOGY, Issue 3 2010Rik Vandenberghe MD Objective The most widely studied positron emission tomography ligand for in vivo ,-amyloid imaging is 11C-Pittsburgh compound B (11C-PIB). Its availability, however, is limited by the need for an on-site cyclotron. Validation of the 18F-labeled PIB derivative 18F-flutemetamol could significantly enhance access to this novel technology. Methods Twenty-seven patients with early-stage clinically probable Alzheimer disease (AD), 20 with amnestic mild cognitive impairment (MCI), and 15 cognitively intact healthy volunteers (HVs) above and 10 HVs below 55 years of age participated. The primary endpoint was the efficacy of blinded visual assessments of 18F-flutemetamol scans in assigning subjects to a raised versus normal uptake category, with clinical diagnosis as the standard of truth (SOT). As secondary objectives, we determined the correlation between the regional standardized uptake value ratios (SUVRs) for 18F-flutemetamol and its parent molecule 11C-PIB in 20 of the AD subjects and 20 of the MCI patients. We also determined test-retest variability of 18F-flutemetamol SUVRs in 5 of the AD subjects. Results Blinded visual assessments of 18F-flutemetamol scans assigned 25 of 27 scans from AD subjects and 1 of 15 scans from the elderly HVs to the raised category, corresponding to a sensitivity of 93.1% and a specificity of 93.3% against the SOT. Correlation coefficients between cortical 18F-flutemetamol SUVRs and 11C-PIB SUVRs ranged from 0.89 to 0.92. Test-retest variabilities of regional SUVRs were 1 to 4%. Interpretation 18F-Flutemetamol performs similarly to the 11C-PIB parent molecule within the same subjects and provides high test-retest replicability and potentially much wider accessibility for clinical and research use. ANN NEUROL 2010 [source] Imaging of amyloid burden and distribution in cerebral amyloid angiopathyANNALS OF NEUROLOGY, Issue 3 2007Keith A. Johnson MD Objective Cerebrovascular deposition of ,-amyloid (cerebral amyloid angiopathy [CAA]) is a major cause of hemorrhagic stroke and a likely contributor to vascular cognitive impairment. We evaluated positron emission tomographic imaging with the ,-amyloid,binding compound Pittsburgh Compound B (PiB) as a potential noninvasive method for detection of CAA. We hypothesized that amyloid deposition would be observed with PiB in CAA, and based on the occipital predilection of CAA pathology and associated hemorrhages, that specific PiB retention would be disproportionately greater in occipital lobes. Methods We compared specific cortical PiB retention in 6 nondemented subjects diagnosed with probable CAA with 15 healthy control subjects and 9 patients with probable Alzheimer's disease (AD). Results All CAA and AD subjects were PiB-positive, both by distribution volume ratio measurements and by visual inspection of positron emission tomographic images. Global cortical PiB retention was significantly increased in CAA (distribution volume ratio 1.18 ± 0.06) relative to healthy control subjects (1.04 ± 0.10; p = 0.0009), but was lower in CAA than in AD subjects (1.41 ± 0.17; p = 0.002). The occipital-to-global PiB ratio, however, was significantly greater in CAA than in AD subjects (0.99 ± 0.07 vs 0.86 ± 0.05; p = 0.003). Interpretation We conclude that PiB-positron emission tomography can detect cerebrovascular ,-amyloid and may serve as a method for identifying the extent of CAA in living subjects. Ann Neurol 2007 [source] | ||||||||||||||||||||||