114 research outputs found
Long Latency and High Variability in Accuracy-Speed of Prosaccades in Alzheimer's Disease at Mild to Moderate Stage
Background: Studying saccades is a useful tool to investigate brain function. There is still controversy regarding deficits in prosaccades in Alzheimer’s disease (AD), and a study of saccades in subjects with mild cognitive impairment (MCI) has not been published to date. Methods: We examined horizontal saccades in 10 healthy elderly, and 9 MCI and 9 AD patients. Two tasks were used: gap (fixation target extinguishes prior to target onset) and overlap (fixation stays on after target onset). Eye movements were recorded with the Skalar IRIS system. Results: (1) Latencies were shorter in the gap than in the overlap task (a gap effect) in all three groups of subjects: healthy elderly, MCI and AD; (2) for both tasks, latency of saccades was longer for AD patients than for healthy and MCI subjects, and (3) accuracy and mean velocity were normal in MCI and AD subjects, however, variability in accuracy-speed was higher for AD patients than for healthy and MCI subjects in the overlap task. Conclusions: Abnormalities in reaction time and accuracy-speed variability reflect deficits in cerebral areas involved in the triggering and execution of saccades; a saccade test can be useful to follow up the evolution of MCI subjects as some of them may develop AD disease
Tofu intake is associated with poor cognitive performance among community-dwelling elderly in China
© 2015 IOS Press and the authors. All rights reserved.Tofu is a soy product which is commonly consumed in Asian countries, such as China and Indonesia. Several studies found negative associations of high tofu consumption with cognitive function in older Asian populations. However, the effect of tofu on cognitive function remains disputed as it was not found in Western populations. In the present study, the effect of weekly tofu intake on cognitive performance was investigated in an observational cross sectional study of 517 Chinese elderly from Shanghai. Similar to earlier studies, results showed that a higher weekly intake of tofu was associated with worse memory performance using the Hopkins Verbal Learning Test (β =-0.10, p = 0.01) after controlling for age, gender, education, being vegetarian, and weekly intake of fruit/juice, green vegetables, and orange/red vegetables. Furthermore, among older elderly (≥68 years of age), high tofu intake increased the risk of cognitive impairment indicative of dementia (OR = 1.27, 95% CI = 0.99-1.64, p = 0.04), after adjusting for all covariates. Consumption of meat and green vegetables independently also reduced risk of dementia. To conclude, high intake of tofu was negatively related to cognitive performance among community-dwelling elderly in China. Similar findings were reported in Indonesia and in Japanese Americans in the US. These findings suggest that the effect of tofu on cognition in elderly should be further investigated
Abnormal Changes of Brain Cortical Anatomy and the Association with Plasma MicroRNA107 Level in Amnestic Mild Cognitive Impairment
MicroRNA107 (Mir107) has been thought to relate to the brain structure phenotype of Alzheimer’s disease. In this study, we evaluated the cortical anatomy in amnestic mild cognitive impairment (aMCI) and the relation between cortical anatomy and plasma levels of Mir107 and beta-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1). Twenty aMCI (20 aMCI) and 24 cognitively normal control (NC) subjects were recruited, and T1-weighted MR images were acquired. Cortical anatomical measurements, including cortical thickness (CT), surface area (SA), and local gyrification index (LGI), were assessed. Quantitative RT-PCR was used to examine plasma expression of Mir107, BACE1 mRNA. Thinner cortex was found in aMCI in areas associated with episodic memory and language, but with thicker cortex in other areas. SA decreased in aMCI in the areas associated with working memory and emotion. LGI showed a significant reduction in aMCI in the areas involved in language function. Changes in Mir107 and BACE1 messenger RNA plasma expression were correlated with changes in CT and SA. We found alterations in key left brain regions associated with memory, language, and emotion in aMCI that were significantly correlated with plasma expression of Mir107 and BACE1 mRNA. This combination study of brain anatomical alterations and gene information may shed lights on our understanding of the pathology of AD
Risk factors for possible dementia using the Hopkins verbal learning test and the mini-mental state examination in Shanghai
Using a combination of the Hopkins Verbal Learning Test (HVLT) and the
Mini-Mental State Examination (MMSE), we investigated the prevalence of possible
dementia (DEM) in community-dwelling elderly in Shanghai. Subsequently, we
investigated significant risk factors for DEM and generated a DEM self-checklist for early
DEM detection and case management. We found that among a total of 521 participants
using a HVLT cut-off score of <19 and a MMSE cut-off score of <24, a total of 69 DEM
cases were identified. Risk factors, such as advanced age (≥68 years), low education (no or
primary level), self-reported history of hypertension, and self-reported subjective memory
complaints (SMC) were significantly predictive of DEM. The presence of ≥3 out of four of the
above mentioned risk factors can effectively discriminate DEM cases from non-DEM subjects
Cluster analysis of physical and cognitive ageing patterns in older people from Shanghai
This study investigated the relationship between education, cognitive and physical function in older age, and their respective impacts on activities of daily living (ADL). Data on 148 older participants from a community-based sample recruited in Shanghai, China, included the following measures: age, education, ADL, grip strength, balance, gait speed, global cognition and verbal memory. The majority of participants in the present cohort were cognitively and physically healthy and reported no problems with ADL. Twenty-eight percent of participants needed help with ADL, with the majority of this group being over 80 years of age. Significant predictors of reductions in functional independence included age, balance, global cognitive function (MMSE) and the gait measures. Cluster analysis revealed a protective effect of education on cognitive function that did not appear to extend to physical function. Consistency of such phenotypes of ageing clusters in other cohort studies may provide helpful models for dementia and frailty prevention measures
Type 2 diabetes mellitus might be a risk factor for mild cognitive impairment progressing to Alzheimer’s disease
Attention-Guided Autoencoder for Automated Progression Prediction of Subjective Cognitive Decline with Structural MRI
Subjective cognitive decline (SCD) is a preclinical stage of Alzheimer's
disease (AD) which occurs even before mild cognitive impairment (MCI).
Progressive SCD will convert to MCI with the potential of further evolving to
AD. Therefore, early identification of progressive SCD with neuroimaging
techniques (e.g., structural MRI) is of great clinical value for early
intervention of AD. However, existing MRI-based machine/deep learning methods
usually suffer the small-sample-size problem which poses a great challenge to
related neuroimaging analysis. The central question we aim to tackle in this
paper is how to leverage related domains (e.g., AD/NC) to assist the
progression prediction of SCD. Meanwhile, we are concerned about which brain
areas are more closely linked to the identification of progressive SCD. To this
end, we propose an attention-guided autoencoder model for efficient
cross-domain adaptation which facilitates the knowledge transfer from AD to
SCD. The proposed model is composed of four key components: 1) a feature
encoding module for learning shared subspace representations of different
domains, 2) an attention module for automatically locating discriminative brain
regions of interest defined in brain atlases, 3) a decoding module for
reconstructing the original input, 4) a classification module for
identification of brain diseases. Through joint training of these four modules,
domain invariant features can be learned. Meanwhile, the brain disease related
regions can be highlighted by the attention mechanism. Extensive experiments on
the publicly available ADNI dataset and a private CLAS dataset have
demonstrated the effectiveness of the proposed method. The proposed model is
straightforward to train and test with only 5-10 seconds on CPUs and is
suitable for medical tasks with small datasets.Comment: 10 pages, 12 figure
Potent anti-tumor effects of a dual specific oncolytic adenovirus expressing apoptin in vitro and in vivo
<p>Abstract</p> <p>Background</p> <p>Oncolytic virotherapy is an attractive drug platform of cancer gene therapy, but efficacy and specificity are important prerequisites for success of such strategies. Previous studies determined that Apoptin is a p53 independent, bcl-2 insensitive apoptotic protein with the ability to specifically induce apoptosis in tumor cells. Here, we generated a conditional replication-competent adenovirus (CRCA), designated Ad-hTERT-E1a-Apoptin, and investigated the effectiveness of the CRCA a gene therapy agent for further clinical trials.</p> <p>Results</p> <p>The observation that infection with Ad-hTERT-E1a-Apoptin significantly inhibited growth of the melanoma cells, protecting normal human epidermal melanocytes from growth inhibition confirmed cancer cell selective adenoviral replication, growth inhibition, and apoptosis induction of this therapeutic approach. The <it>in vivo </it>assays performed by using C57BL/6 mice containing established primary or metastatic tumors expanded the <it>in vitro </it>studies. When treated with Ad-hTERT-E1a-Apoptin, the subcutaneous primary tumor volume reduction was not only observed in intratumoral injection group but in systemic delivery mice. In the lung metastasis model, Ad-hTERT-E1a-Apoptin effectively suppressed pulmonary metastatic lesions. Furthermore, treatment of primary and metastatic models with Ad-hTERT-E1a-Apoptin increased mice survival.</p> <p>Conclusions</p> <p>These data further reinforce the previously research showing that an adenovirus expressing Apoptin is more effective and advocate the potential applications of Ad-hTERT-E1a-Apoptin in the treatment of neoplastic diseases in future clinical trials.</p
Alcohol Consumption and Subclinical Findings on Cognitive Function, Biochemical Indexes, and Cortical Anatomy in Cognitively Normal Aging Han Chinese Population
Background: Binge drinking of alcohol is associated with brain damage, but less is known about relationship of light-to-moderate alcohol consumption with cognitive function, biochemical indexes, and cortical anatomy. Previous findings have debated on whether light-to-moderate drinking has any health benefits. We investigated cortical thickness and its association with alcohol consumption and cognitive functions in a non-dementia aging Han Chinese population.Methods: 940 non-dementia aging subjects were included in our study (alcohol n = 149; non-alcohol n = 791). Among them, 572 received blood biochemical tests including liver function and lipid metabolism (alcohol n = 100; non-alcohol n = 472) and 141 had brain magnetic resonance imaging (alcohol n = 27; non-alcohol n = 114). The Beijing version of the Montreal Cognitive Assessment and the Chinese version of the neuropsychological test battery were used to assess cognitive functions.Results: There was no significant difference in cognitive functions between alcohol and non-alcohol groups in the overall database. Similarly, there was no significant difference in liver function and lipid metabolism between two groups in the sub-database. The left superiortemporal gyrus was one of age sensitive regions and alcohol consumption was significantly associated with thinner cortex of the left superiotemporal cluster in the sub-database.Conclusion: Alcohol consumption was not significantly associated with better or worse cognitive function and biochemical indexes abnormality, however, significantly associated with thinner cortex of the left superiortemporal gyrus in cognitively normal aging Han Chinese population
COSMIC (Cohort Studies of Memory in an International Consortium): An international consortium to identify risk and protective factors and biomarkers of cognitive ageing and dementia in diverse ethnic and sociocultural groups
BACKGROUND: A large number of longitudinal studies of population-based ageing cohorts are in progress internationally, but the insights from these studies into the risk and protective factors for cognitive ageing and conditions like mild cognitive impairment and dementia have been inconsistent. Some of the problems confounding this research can be reduced by harmonising and pooling data across studies. COSMIC (Cohort Studies of Memory in an International Consortium) aims to harmonise data from international cohort studies of cognitive ageing, in order to better understand the determinants of cognitive ageing and neurocognitive disorders.
METHODS/DESIGN: Longitudinal studies of cognitive ageing and dementia with at least 500 individuals aged 60 years or over are eligible and invited to be members of COSMIC. There are currently 17 member studies, from regions that include Asia, Australia, Europe, and North America. A Research Steering Committee has been established, two meetings of study leaders held, and a website developed. The initial attempts at harmonising key variables like neuropsychological test scores are in progress.
DISCUSSION: The challenges of international consortia like COSMIC include efficient communication among members, extended use of resources, and data harmonisation. Successful harmonisation will facilitate projects investigating rates of cognitive decline, risk and protective factors for mild cognitive impairment, and biomarkers of mild cognitive impairment and dementia. Extended implications of COSMIC could include standardised ways of collecting and reporting data, and a rich cognitive ageing database being made available to other researchers. COSMIC could potentially transform our understanding of the epidemiology of cognitive ageing, and have a world-wide impact on promoting successful ageing
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