Search results for "Geriatrics"

Cholesterol and Amyloid-β: Evidence for a Cross-Talk between Astrocytes and Neuronal Cells.

2011

Accumulating data supports the concept that alterations of cholesterol metabolism might influence the development of Alzheimer's disease (AD), a neurodegenerative disorder characterized by progressive accumulation of amyloid-β (Aβ) peptides in the brain. Changes in the neuronal production of Aβ have been described as a function of cholesterol levels, thus suggesting a causal link between cholesterol homeostasis dysregulation and AD pathogenesis. Under physiological conditions, cholesterol uptake in the brain is efficiently prevented by the blood-brain barrier, and mature neurons are thought to rely on glial cells for their cholesterol supply. In the present study, we tested the hypothesis t…

P3‐039: Axonal neuritic pathology induces early presynaptic alterations in ps1/APP Alzheimer's mice hippocampus

2011

Loss of neurons in the hippocampus correlates with memory impairment in AD. Significant early reduction in the numerical density of hippocampal SOM interneurons was found in single (APPswe) and double (APPswe/ PS1dE9 and APPswe/TauP301S-G272V) transgenic models based on APP over expression and amyloid production. However, this inhibitory population was unaffected in age-matched single PS1 and tau transgenic mice as well as nontransgenic controls. Whereas SOM neuron loss in APPswe/PS1dE9 was associated to the onset of extracellular amyloid pathology in double APP/ tau mice this loss preceded plaque formation. Conclusions: As in human AD, somatostatin cell loss is a common early pathological …

DETERMINANTS OF DNA METHYLATION BASED AGE ACCELERATION IN YOUNG AND OLDER TWIN PAIRS

2017

DNA methylation (DNAm) age, a novel marker of biological aging, has been shown to predict mortality and to be associated with physiological aging. However, the relative contribution of genetic and environmental factors to DNAm age over life span is not fully known. We estimated the magnitude of genetic and environmental factors in DNAm based age acceleration.

Analysis of HLA-DQA, HLA-DQB frequencies in a group of Sardinian centenarians

2006

Human leukocyte antigen (HLA) alleles, regulating type and intensity of the immune response, might influence life expectancy. In previous case-control studies the authors have demonstrated that both HLA-DR and -DQ alleles are not associated with longevity in the Sardinian population. On the other hand, association studies are subjected (as part of the homogeneity of the population in terms of geographic origin) to a number of possible confounding factors. Therefore, the authors typed the HLA-DQA1 and HLA-DQB1 alleles in 24 sibs (age range 85 to 97) of 17 centenarians by PCR-SSP. Sib pair analysis showed non-significant differences between the observed and expected percentage of DQA* or DQB1…

Does Down's syndrome support the homocysteine theory of atherogenesis?

2006

Abstract Down syndrome (DS) is generally considered as an “atheroma-free model”. In this preliminary study, we investigated homocysteine, folate and Vitamin B 12 levels in 13 DS patients (male, average age 60 years) and 20 age-matched individuals. We also studied lipid fractions, and polymorphisms for Cystothionine β-synthase (CBS), 5,10-methyl-tetrahydro-folate reductase (MTHFR) and apolipoprotein E (Apo-E) genes. However, DS patients with the MTHFR TT genotype showed an increased of plasma homocysteine (tHcy). Our results indicate that this group of “healthy old” Down syndrome patients, although showing some classical biochemical risk factors for atherosclerosis, did not suffer clinical c…

P2‐077: Identification of potential modifiers of Alzheimer's disease pathology by quantitative mass spectrometry and drosophila genetics

2015

Environmental Features Associated With Older Adults' Physical Activity in Different Types of Urban Neighborhoods.

2020

The authors studied associations of nature- and infrastructure-based features with physical activity (PA) in different urban neighborhood types; 848 community-dwelling people aged 75–90 years reported PA and three perceived nature-based destinations and seven infrastructure-based features as outdoor mobility facilitators. Neighborhood type was defined using a geographic information system based on proximity to central service areas and residential density (city center, subcenter, and dense and dispersed areas outside centers). PA was higher in dense areas and the city center. Binary logistic regression showed that perceiving nature-based destinations increased the odds for higher PA in the …

Thoracic kyphosis and ventilatory dysfunction in unselected older persons: an epidemiological study in Dicomano, Italy.

2004

OBJECTIVES: To assess whether kyphosis is associated with ventilatory dysfunction in older community dwellers. DESIGN: Cross-sectional study. SETTING: The unselected population of Dicomano, Italy aged>or=65 years. PARTICIPANTS: A total of 323 nonheart failure participants underwent clinical evaluation for the presence of kyphosis and spirometry. The severity of kyphosis was estimated from the difference between standing stature and knee-height-derived stature and from the occiput-wall distance. MEASUREMENTS: Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and prevalence of obstructive and restrictive ventilatory pattern. RESULTS: The 130 kyphotic participants (40.2…

Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Eff…

2015

Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target related P300 for the expected antonym ("white"; an eff…

El derecho como institución espontánea

2021

En este artículo trataremos de mostrar la viabilidad y con-veniencia de un orden jurídico descentralizado frente a una or-ganización monocéntrica que genere e imponga sus propios mandatos jurídicos.
 En la primera parte, comenzaremos con al análisis haye-kiano del orden espontáneo para explicar las distintas carac-terísticas y etapas que componen una institución. En la se-gunda, aplicaremos estas conclusiones al caso particular del derecho.
 Con este análisis podremos elaborar ciertas predicciones y explicaciones sobre la evolución política del Estado y pergeñar estrategias para lograr defender la libertad.
 Para Hayek las instituciones sociales «no sólo no han sido creadas p…