Age-related cognitive decline (ARCD) leads to deterioration of the quality of life in the elderly. Because emerging evidence suggests age-related illness is associated with gene regulation, it is ...necessary to understand the factors related to ARCD from an epigenetic perspective to aim for successful cognitive aging (SCA). This study aimed to identify biomarkers for SCA by comparing peripheral blood DNA methylation profiles of community-dwelling older adults with SCA and normal cognitive aging (NCA). We selected 14 SCA participants with scores for all cognitive functions (four domains, namely global cognitive, memory, attention, and executive function) above the average of normative values in Korean older adults and 15 NCA participants from the Korean Frailty Aging Cohort Study (KFACS). We performed methylation microarrays to compare the level of DNA methylation at CpG sites in the SCA and NCA groups. We also validated our findings using gene expression analysis. We found significant differences in eight differentially methylated genes (DMGs)—two hypermethylated genes (IL26 and LOC101060542) and six hypomethylated genes (CEND1, GNAT2, SNORD95, miR885, LOC255167, and HK2). CEND1 (fold change = 5.67) and miR885 (fold change = 8.91) were validated as having significantly different gene expressions between the SCA and NCA groups. Therefore, we postulate them to be potentially promising biomarkers to explain SCA attainment. These findings provide preliminary evidence for understanding SCA and assessing cognitive health in aging.
•Eight differentially methylated genes were identified between successful cognitive aging and normal cognitive aging.•CEND1 and miR885 were validated by gene expression analysis.•CEND1 and miR885 methylation changes can be used biomarkers for successful cognitive aging attainment.
Understanding the role of smartphones to promote the health status of older adults is important in the digital society. Little is known about the effects of having smartphones on physical frailty ...despite its positive effect on the well-being of older adults. This study aimed to explore the association between smartphone ownership and frailty in community-dwelling older adults and its underlying mechanism.
We used data from the Korean Frailty and Aging Cohort Study and analyzed 2,469 older adults aged 72-86 years. Frailty, health literacy, and social support were assessed by Fried's frailty phenotype, the Behavioral Risk Factor Surveillance System health literacy module, and the Enhancing Recovery in Coronary Heart Disease (ENRICHD) Social Support Instrument, respectively. The mediation model and moderated mediation model were estimated, where the mediator was health literacy and the moderator was social support, to explore the relationship between smartphone ownership and frailty.
Of our study participants, 58.9% owned smartphones, and 10.9% were classified as frail. Smartphone ownership was negatively associated with frailty (β = -0.623, p < 0.001). Health literacy mediated the relationship between smartphone ownership and frailty (β = -0.154, boot confidence interval CI = - 0.222, - 0.096), and social support moderated the mediation effect (β = -0.010, Boot CI = - 0.016, - 0.004).
Owning smartphones among older adults could reduce the risk of frailty. Promoting health literacy and social support among older adults with smartphones would be effective to prevent frailty.
Background and Purpose
There is a scarcity of information regarding the role of prothrombin kringle‐2 (pKr‐2), which can be generated by active thrombin, in hippocampal neurodegeneration and ...Alzheimer's disease (AD).
Experimental Approach
To assess the role of pKr‐2 in association with the neurotoxic symptoms of AD, we determined pKr‐2 protein levels in post‐mortem hippocampal tissues of patients with AD and the hippocampi of five familial AD (5XFAD) mice compared with those of age‐matched controls and wild‐type (WT) mice, respectively. In addition, we investigated whether the hippocampal neurodegeneration and object memory impairments shown in 5XFAD mice were mediated by changes to pKr‐2 up‐regulation.
Key Results
Our results demonstrated that pKr‐2 was up‐regulated in the hippocampi of patients with AD and 5XFAD mice, but was not associated with amyloid‐β aggregation in 5XFAD mice. The up‐regulation of pKr‐2 expression was inhibited by preservation of the blood–brain barrier (BBB) via addition of caffeine to their water supply or by treatment with rivaroxaban, an inhibitor of factor Xa that is associated with thrombin production. Moreover, the prevention of up‐regulation of pKr‐2 expression reduced neurotoxic symptoms, such as hippocampal neurodegeneration and object recognition decline due to neurotoxic inflammatory responses in 5XFAD mice.
Conclusion and Implications
We identified a novel pathological mechanism of AD mediated by abnormal accumulation of pKr‐2, which functions as an important pathogenic factor in the adult brain via blood brain barrier (BBB) breakdown. Thus, pKr‐2 represents a novel target for AD therapeutic strategies and those for related conditions.
Motoric cognitive risk (MCR) syndrome is originally defined as the presence of subjective cognitive complaints (SCCs) and slow gait (SG). MCR is well known to be useful for predicting adverse health ...outcomes, including falls and dementia. However, around four out of five older Korean adults reported SCCs, thereby, it may not be discriminative to define MCR in Korea. We adopted the three-item recall (3IR) test, instead of SCCs, to define MCR. This cross-sectional analysis included 2133 community-dwelling older adults aged 70-84 years, without dementia or any dependence in activities of daily living from the Korean Frailty and Aging Cohort Study. The newly attempted criteria of MCR using 3IR were met by 105 participants (4.9%). MCR using 3IR showed synergistic effects on fall-related outcomes, whereas the conventional definition of MCR using SCCs was not superior to SG only. MCR using 3IR was associated with falls (odds ratio OR: 1.92; 95% confidence interval (CI): 1.16-3.16), recurrent falls (OR: 2.19; 95% CI: 1.12-4.32), falls with injury (OR: 1.98; 95% CI: 1.22-3.22), falls with fracture (OR: 2.51; 95% CI: 1.09-5.79), fear of falling (OR: 3.00; 95% CI: 1.83-4.92), and low activities-specific balance confidence (OR: 3.13; 95% CI: 1.57-6.25). We found that MCR using 3IR could be useful in predicting fall-related outcomes in a cultural background reporting more SCCs, such as Korea.
The sleep-promoting effects of the water extract of Nelumbo nucifera seeds (NNE) were investigated in an invertebrate model. The effects of NNE on the subjective nighttime activity, sleep episodes, ...and sleep time were determined using Drosophila melanogaster and locomotor activity monitoring systems in basal and caffeine-induced arousal conditions. The movements of fruit flies were analyzed using the Noldus EthoVision-XT system, and the levels of neuromodulators were analyzed using HPLC. Expression of neuromodulator receptors was analyzed using real-time PCR. NNE was shown to contain neurotransmission-related components; γ-aminobutyric acid (GABA) (2.33±0.22 mg/g), tryptophan (2.00±0.06 mg/g), quinidine (0.55±0.33 mg/g), and neferine (0.16±0.01 mg/g). The total activity of flies during nighttime was decreased by 52% with 1.0% NNE treatment. In the individual and collective conditions, the subjective nighttime activities (45/38%) and sleep bouts (20/14%) of flies was significantly decreased with NNE treatment, while total sleep times (10/27%) were significantly increased. This sleep-promoting effect is more pronounced in caffeine-treated conditions; the nighttime activity of flies was reduced by 53%, but total sleep time was increased by 60%. Our video-tracking analysis showed a significant decrease of the moving distance and velocity of flies by NNE. This NNE-mediated sleep-promoting effect was associated with up-regulation of GABAA/GABAB and serotonin receptors. The NNE-mediated increase of GABA content was identified in flies. These results demonstrate that NNE effectively promotes sleep in flies by regulating the GABAergic/serotonergic neuromodulators, and could be an alternative agent for sleep promotion.
Synthesis of 1-benzazepines has been achieved via a 1,5-hydride shift/7-endo cyclization sequence. The focus of this research is a direct transformation of 2-(aryl)cyclopropane 1,1-diester ...derivatives into 1-benzazepines using a cyclopropane moiety as the hydride acceptor in internal redox reactions.
We present 850 m polarization observations of the L1689 molecular cloud, part of the nearby Ophiuchus molecular cloud complex, taken with the POL-2 polarimeter on the James Clerk Maxwell Telescope ...(JCMT). We observe three regions of L1689: the clump L1689N which houses the IRAS 16293-2433 protostellar system, the starless clump SMM-16, and the starless core L1689B. We use the Davis-Chandrasekhar-Fermi method to estimate plane-of-sky field strengths of 366 55 G in L1689N, 284 34 G in SMM-16, and 72 33 G in L1689B, for our fiducial value of dust opacity. These values indicate that all three regions are likely to be magnetically transcritical with sub-Alfvénic turbulence. In all three regions, the inferred mean magnetic field direction is approximately perpendicular to the local filament direction identified in Herschel Space Telescope observations. The core-scale field morphologies for L1689N and L1689B are consistent with the cloud-scale field morphology measured by the Planck Space Observatory, suggesting that material can flow freely from large to small scales for these sources. Based on these magnetic field measurements, we posit that accretion from the cloud onto L1689N and L1689B may be magnetically regulated. However, in SMM-16, the clump-scale field is nearly perpendicular to the field seen on cloud scales by Planck, suggesting that it may be unable to efficiently accrete further material from its surroundings.
Demand on optical or photonic applications in the visible or short-wavelength infrared (SWIR) spectra, such as vision, virtual or augmented displays, imaging, spectroscopy, remote sensing (LIDAR), ...chemical reaction sensing, microscopy, and photonic integrated circuits, has envisaged new type of subwavelength-featured materials and devices for controlling electromagnetic waves. The study on metasurfaces, of which the thickness is either comparable to or smaller than the wavelength of the considered incoming electromagnetic wave, has been grown rapidly to embrace the needs of developing sub 100-micron active photonic pixelated devices and their arrayed form. Meta-atoms in metasurfaces are now actively controlled under external stimuli to lead to a large phase shift upon the incident light, which has provided a huge potential for arrayed two-dimensional active optics. This short review summarizes actively tunable or reconfigurable metasurfaces for the visible or SWIR spectra, to account for the physical operating principles and the current issues to overcome.
We present a new controllable superflash, a maximum transient peak at the falling edge of a square pulse, using a three-level electromagnetically induced transparency (EIT). The superflash in a ...two-level system occurs at a certain value of the detuning of the probe laser (Δ peak ) when the optical depth (OD) of the medium is sufficiently large and constant. Here, we show the external tunability of the Δ peak for obtaining the maximum transient peak by introducing a three-level EIT. Owing to the EIT dispersion properties, we effectively tune the phase of the forward-scattered light ( E s ) by externally controlling the EIT coupling light intensities associated with the Rabi frequency (Ω c ). When the incident light is turned off, the total transmitted field ( E t ) experiences an out-of-phase shift, producing a peak intensity that is three times higher than the input. We observe that this new class of superflash (Type II) occurs near the EIT window and exhibits inverse-linearity of the OD, which is in contrast with the characteristics of the previously reported two-level superflash (Type I). Furthermore, we find the quadratic nature of tunability in Δ peak (Ω c ).The new tunability of the superflash by the Rabi frequency may facilitate more rapid and effective control of the superflash compared to a passive optical medium.
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