Social and Behavioral Sciences Commons^™

Post-Acquisition Processing Confounds In Brain Volumetric Quantification Of White Matter Hyperintensities, Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha

Neurology Faculty Publications

BACKGROUND: Disparate research sites using identical or near-identical magnetic resonance imaging (MRI) acquisition techniques often produce results that demonstrate significant variability regarding volumetric quantification of white matter hyperintensities (WMH) in the aging population. The sources of such variability have not previously been fully explored.

NEW METHOD: 3D FLAIR sequences from a group of randomly selected aged subjects were analyzed to identify sources-of-variability in post-acquisition processing that can be problematic when comparing WMH volumetric data across disparate sites. The methods developed focused on standardizing post-acquisition protocol processing methods to develop a protocol with less than 0.5% inter-rater variance.

RESULTS: A series …

Influence Of Dietary Salt Knowledge, Perceptions, And Beliefs On Consumption Choices After Stroke In Uganda, Martin N. Kaddumukasa, Elly Katabira, Martha Sajatovic, Svetlana Pundik, Mark Kaddumukasa, Larry B. Goldstein

Neurology Faculty Publications

Background

Previous research on Uganda's poststroke population revealed that their level of dietary salt knowledge did not lead to healthier consumption choices.

Purpose

Identify barriers and motivators for healthy dietary behaviors and evaluate the understanding of widely accepted salt regulation mechanisms among poststroke patients in Uganda.

Methods

Convergent parallel mixed methods triangulation design comprised a cross-sectional survey (n = 81) and 8 focus group discussions with 7-10 poststroke participants in each group. We assessed participant characteristics and obtained insights into their salt consumption attitudes, perceptions, and knowledge. Qualitative responses were analyzed using an inductive approach with thematic analytic procedures. Relationships …

Csf Protein Changes Associated With Hippocampal Sclerosis Risk Gene Variants Highlight Impact Of Grn/Pgrn, David W. Fardo, Yuriko Katsumata, John S. K. Kauwe, Yuetiva Deming, Oscar Harari, Carlos Cruchaga, Alzheimer’S Disease Neuroimaging Initiative, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

Objective—Hippocampal sclerosis of aging (HS-Aging) is a common cause of dementia in older adults. We tested the variability in cerebrospinal fluid (CSF) proteins associated with previously identified HS-Aging risk single nucleotide polymorphisms (SNPs).

Methods—Alzheimer’s Disease Neuroimaging Initiative cohort (ADNI; n=237) data, combining both multiplexed proteomics CSF and genotype data, were used to assess the association between CSF analytes and risk SNPs in four genes (SNPs): GRN (rs5848), TMEM106B (rs1990622), ABCC9 (rs704180), and KCNMB2 (rs9637454). For controls, non-HS-Aging SNPs in APOE (rs429358/rs7412) and MAPT (rs8070723) were also analyzed against Aβ1-42 and total tau CSF analytes.

Results—The GRN risk …

Discrimination Of Mild Cognitive Impairment And Alzheimer's Disease Using Transfer Entropy Measures Of Scalp Eeg, Joseph Mcbride, Xiaopeng Zhao, Nancy Munro, Gregory Jicha, Charles Smith, Yang Jiang

Sanders-Brown Center on Aging Faculty Publications

Mild cognitive impairment (MCI) is a neurological condition related to early stages of dementia including Alzheimer's disease (AD). This study investigates the potential of measures of transfer entropy in scalp EEG for effectively discriminating between normal aging, MCI, and AD participants. Resting EEG records from 48 age-matched participants (mean age 75.7 years)-15 normal controls, 16 MCI, and 17 early AD-are examined. The mean temporal delays corresponding to peaks in inter-regional transfer entropy are computed and used as features to discriminate between the three groups of participants. Three-way classification schemes based on binary support vector machine models demonstrate overall discrimination accuracies …

Sugihara Causality Analysis Of Scalp Eeg For Detection Of Early Alzheimer's Disease, Joseph C. Mcbride, Xiaopeng Zhao, Nancy B. Munro, Greg A. Jicha, Frederick A. Schmitt, Richard J. Kryscio, Charles D. Smith, Yang Jiang

Sanders-Brown Center on Aging Faculty Publications

Recently, Sugihara proposed an innovative causality concept, which, in contrast to statistical predictability in Granger sense, characterizes underlying deterministic causation of the system. This work exploits Sugihara causality analysis to develop novel EEG biomarkers for discriminating normal aging from mild cognitive impairment (MCI) and early Alzheimer's disease (AD). The hypothesis of this work is that scalp EEG based causality measurements have different distributions for different cognitive groups and hence the causality measurements can be used to distinguish between NC, MCI, and AD participants. The current results are based on 30-channel resting EEG records from 48 age-matched participants (mean age 75.7 …

Practice Effects In A Longitudinal, Multi-Center Alzheimer's Disease Prevention Clinical Trial, Erin L. Abner, Brandon C. Dennis, Melissa J. Mathews, Marta S. Mendiondo, Allison Caban-Holt, Richard J. Kryscio, Frederick A. Schmitt, John J. Crowley

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Practice effects are a known threat to reliability and validity in clinical trials. Few studies have investigated the potential influence of practice on repeated screening measures in longitudinal clinical trials with a focus on dementia prevention. The current study investigates whether practice effects exist on a screening measure commonly used in aging research, the Memory Impairment Screen (MIS).

METHODS: The PREADViSE trial is a clinical intervention study evaluating the efficacy of vitamin E and selenium for Alzheimer's disease prevention. Participants are screened annually for incident dementia with the MIS. Participants with baseline and three consecutive follow-ups who made less …

Elevated Stearoyl-Coa Desaturase In Brains Of Patients With Alzheimer's Disease, Giuseppe Astarita, Kwang-Mook Jung, Vitaly Vasilevko, Nicholas V. Dipatrizio, Sarah K. Martin, David H. Cribbs, Elizabeth Head, Carl W. Cotman, Daniele Piomelli

Sanders-Brown Center on Aging Faculty Publications

The molecular bases of Alzheimer's disease (AD) remain unclear. We used a lipidomic approach to identify lipid abnormalities in the brains of subjects with AD (N = 37) compared to age-matched controls (N = 17). The analyses revealed statistically detectable elevations in levels of non-esterified monounsaturated fatty acids (MUFAs) and mead acid (20:3n-9) in mid-frontal cortex, temporal cortex and hippocampus of AD patients. Further studies showed that brain mRNAs encoding for isoforms of the rate-limiting enzyme in MUFAs biosynthesis, stearoyl-CoA desaturase (SCD-1, SCD-5a and SCD-5b), were elevated in subjects with AD. The monounsaturated/saturated fatty acid ratio ('desaturation index')--displayed a strong …

Epigenetic Silencing Of Nucleolar Rrna Genes In Alzheimer's Disease, Maciej Pietrzak, Grzegorz Rempala, Peter T. Nelson, Jing-Juan Zheng, Michal Hetman

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Ribosomal deficits are documented in mild cognitive impairment (MCI), which often represents an early stage Alzheimer's disease (AD), as well as in advanced AD. The nucleolar rRNA genes (rDNA), transcription of which is critical for ribosomal biogenesis, are regulated by epigenetic silencing including promoter CpG methylation.

METHODOLOGY/PRINCIPAL FINDINGS: To assess whether CpG methylation of the rDNA promoter was dysregulated across the AD spectrum, we analyzed brain samples from 10 MCI-, 23 AD-, and, 24 age-matched control individuals using bisulfite mapping. The rDNA promoter became hypermethylated in cerebro-cortical samples from MCI and AD groups. In parietal cortex, the rDNA promoter …

Deficient Liver Biosynthesis Of Docosahexaenoic Acid Correlates With Cognitive Impairment In Alzheimer's Disease, Giuseppe Astarita, Kwang-Mook Jung, Nicole C. Berchtold, Vinh Q. Nguyen, Daniel L. Gillen, Elizabeth Head, Carl W. Cotman, Daniele Piomelli

Sanders-Brown Center on Aging Faculty Publications

Reduced brain levels of docosahexaenoic acid (C22:6n-3), a neurotrophic and neuroprotective fatty acid, may contribute to cognitive decline in Alzheimer's disease. Here, we investigated whether the liver enzyme system that provides docosahexaenoic acid to the brain is dysfunctional in this disease. Docosahexaenoic acid levels were reduced in temporal cortex, mid-frontal cortex and cerebellum of subjects with Alzheimer's disease, compared to control subjects (P = 0.007). Mini Mental State Examination (MMSE) scores positively correlated with docosahexaenoic/α-linolenic ratios in temporal cortex (P = 0.005) and mid-frontal cortex (P = 0.018), but not cerebellum. Similarly, liver docosahexaenoic acid content was lower in Alzheimer's …