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The skin is subjected to various external factors that contribute to aging including oxidative stress from hydrogen peroxide (H2O2). This study investigated the distribution of aquaporin-8 (AQP8), a protein that transports H2O2 across biological membranes, in skin cells, and its effects in mitigating H2O2-induced oxidative damage. Human dermal fibroblasts were treated with increasing concentrations of H2O2 to evaluate oxidative damage. Cell viability, reactive oxygen species (ROS) generation, and the expression of specific genes associated with skin aging (IL-10, FPR2, COL1A1, KRT19, and Aggrecan) were evaluated and AQP8 expression was assessed via quantitative polymerase chain reaction and western blotting. Small-interfering RNA was used to silence the AQP8 gene and evaluate its significance. The results show that H2O2 treatment reduces cell viability and increases ROS generation, leading to oxidative damage that affects the expression of target molecules. Interestingly, H2O2-treated cells exhibit high levels of AQP8 expression and gene silencing of AQP8 reverses high levels of ROS and low levels of COL1A1, KRT19, and Aggrecan expression in stressed cells, indicating that AQP8 plays a vital role in preventing oxidative damage and consequent aging. In conclusion, AQP8 is upregulated in human dermal fibroblasts during H2O2-induced oxidative stress and may help prevent oxidative damage and aging. These findings suggest that AQP8 could be a potential therapeutic target for skin aging. Further research is necessary to explore the feasibility of using AQP8 as a preventive or therapeutic strategy for maintaining skin health.

Studies have suggested that visually presented words are obligatorily decomposed into constituents that could be mapped to language representations. The present study aims to elucidate how orthographic processing of one constituent affects the other and vice versa during a word recognition task. Chinese orthographic system has characters representing syllables and meanings instead of suffixation roles, and the majority of Chinese characters are phonograms that can be further decomposed into phonetic radical and semantic radical. We propose that semantic radical combinability indexed by semantic radicals and the effect of phonological consistency indexed by phonetic radicals would interact with each other during the reading of Chinese phonograms. Twenty-six right-handed native Chinese speakers were recruited to the study. Participants were presented with phonograms divided into four conditions following their semantic radical combinability (large vs. small) and phonological consistency (high vs. low). EEG signals were recorded throughout the covert naming task. Our results show that there is an interaction effect between phonological consistency and semantic radical combinability on the right hemisphere N170 activity while reading phonograms. Semantic radical combinability influenced the right hemisphere N170 during the process of low-consistency character reading but not high-consistency character reading. On the other hand, the left hemisphere N170 revealed a more significant activity during reading high-consistency characters and was not affected by radical combinability. In addition, while low-consistency characters revealed a larger P200 than high-consistency characters, the semantic radical combinability effect on P200 was only significant when participants were reading high-consistency characters but not low-consistency characters. These results provide new information about how ERPs are involved in word recognition within the context of interaction among orthographic and phonological dimensions.

Neural decoding is useful to explore the timing and source location in which the brain encodes information. Higher classification accuracy means that an analysis is more likely to succeed in extracting useful information from noises. In this paper, we present the application of a nonlinear, nonstationary signal decomposition technique-the empirical mode decomposition (EMD), on MEG data. We discuss the fundamental concepts and importance of nonlinear methods when it comes to analyzing brainwave signals and demonstrate the procedure on a set of open-source MEG facial recognition task dataset. The improved clarity of data allowed further decoding analysis to capture distinguishing features between conditions that were formerly over-looked in the existing literature, while raising interesting questions concerning hemispheric dominance to the encoding process of facial and identity information.

The development of electrodes capable of maintaining strong adhesion and conductivity in wet environments is crucial for a wide range of electronic applications. From underwater monitoring systems to biomedical devices, the limitations of conventional electrodes pose a significant challenge. Inspired by the adhesive and self-healing properties of marine mussels, this work introduces a self-healing conductive adhesive that not only adheres tenaciously to various surfaces in wet conditions but also demonstrates exceptional conductivity for reliable detection of electrophysiological signals. In this study, our biocompatible adhesive consists of a boronic ester-based polyvinyl alcohol hydrogel with polydopamine particles (PVA/Borax/PDAP). Borate ions enable rapid self-healing (within 10 seconds) by forming dynamic bonds with hydroxyl groups, while the π–π interactions of PDAPs enhance adhesion strength (121 kPa). The inclusion of saturated saline further improves both stretchability (up to ∼1000%) and conductivity (38.3 mS cm−1). We successfully demonstrate the utility of this self-healing conductive adhesive in recording electrophysiological signals, including electroencephalography (EEG), electrodermal activity detection, and electrocardiograms, highlighting its potential for next-generation biomedical wearable devices. [ABSTRACT FROM AUTHOR]

The locus coeruleus‐norepinephrine (LC‐NE) system, which regulates arousal levels, is important for cognitive control, including emotional conflict resolution. Additionally, the LC‐NE system is implicated in P300 generation. If the P300 is mediated by the LC‐NE system, and considering the established correlations between LC activity and pupil dilation, P300 amplitude should correlate with task‐evoked (phasic) pupil dilation on a trial‐by‐trial basis. However, prior studies, predominantly utilizing oddball‐type paradigms, have not demonstrated correlations between concurrently recorded task‐evoked pupil dilation and P300 responses. Using a recently developed emotional face‐word Stroop task that links pupil dilation to the LC‐NE system, here, we examined both intra‐ and inter‐individual correlations between task‐evoked pupil dilation and P300 amplitude. We found that lower accuracy, slower reaction times, and larger task‐evoked pupil dilation were obtained in the incongruent compared to the congruent condition. Furthermore, we observed intra‐individual correlations between task‐evoked pupil dilation and P300 amplitude, with larger pupil dilation correlating with a greater P300 amplitude. In contrast, pupil dilation did not exhibit consistent correlations with N450 and N170 amplitudes. Baseline (tonic) pupil size also showed correlations with P300 and N170 amplitudes, with smaller pupil size corresponding to larger amplitude. Moreover, inter‐individual differences in task‐evoked pupil dilation between the congruent and incongruent conditions correlated with differences in reaction time and P300 amplitude, though these effects only approached significance. To summarize, our study provides evidence for a connection between task‐evoked pupil dilation and P300 amplitude at the single‐trial level, suggesting the involvement of the LC‐NE system in P300 generation. The locus coeruleus‐norepinephrine system is implicated in the generation of the P300. Using pupillometry as an indirect measure of locus coeruleus‐norepinephrine activity, we demonstrated intra‐individual trial‐to‐trial correlations between concurrently recorded task‐evoked pupil dilation and P300 responses in the emotional face‐word Stroop task, with larger pupil dilation correlating with a greater P300 amplitude, suggesting the involvement of the locus coeruleus‐norepinephrine system in P300 generation. [ABSTRACT FROM AUTHOR]

This study used the lexicality effects on N400 to investigate orthographic processing in children with developmental dyslexia. Participants performed a Go/No-Go semantic judgment task; three types of stimuli--real characters (RC), pseudocharacters (PC), and noncharacters (NC)--were embedded in No-Go trials. Two types of lexicality effects (RC vs. NC and PC vs. NC) were used to reflect the sensitivity to Chinese orthographic knowledge. In typical developing children, NC elicited a more negative N400 in frontal sites and a less negative N400 in bilateral posterior sites than RC and PC. The reversed lexicality effects in anterior and posterior sites support the dual-mechanism for lexical retrieval. Children with dyslexia revealed a more negative N400 for NC in frontal sites compared with RC, suggesting that they remained sensitive to orthographic familiarity. However, no difference between NC and PC was observed, suggesting a weakness in capturing Chinese orthographic knowledge in children with dyslexia.

We employ a linear mixed-effects model to estimate the effects of visual form and the linguistic properties of Chinese characters on M100 and M170 MEG responses from single-trial data of Chinese and English speakers in a Chinese lexical decision task. Cortically constrained minimum-norm estimation is used to compute the activation of M100 and M170 responses in functionally defined regions of interest. Both Chinese and English participants' M100 responses tend to increase in response to characters with a high numbers of strokes. English participants' M170 responses show a posterior distribution and only reflect the effect of the visual complexity of characters. On the other hand, the Chinese participants' left hemisphere M170 is increased when reading characters with high number of strokes, and their right hemisphere M170 is increased when reading characters with small combinability of semantic radicals. Our results suggest that expertise with words and the decomposition of word forms underlies processing in the left and right occipitotemporal regions in the reading of Chinese characters by Chinese speakers.

In this study, event-related potentials (ERPs) were used to trace the temporal dynamics of phonological consistency and phonetic combinability in the reading of Chinese phonograms. The data showed a significant consistency-by-combinability interaction at N170. High phonetic combinability characters elicited greater negativity at N170 than did low phonetic combinability characters, and the combinability effect was only found in the reading of high consistency characters. The results support the phonological mapping hypothesis of the reading-related N170 effect and suggest that the earlier stages of visual word recognition are shaped by the mapping of orthography to phonology even in Chinese. Moreover, our data revealed both consistency and combinability effects at P200 and N400, accounted for by the two-stage framework for visual word recognition. That is, characters with high combinability or high consistency facilitated the earlier stages of orthographic or phonological processing which were due to increased activation at the perceptual level; consequently, less positive P200 was demonstrated. In the later stages, high combinability or high consistency characters were associated with a larger semantic neighborhood, which increased semantic competition and exaggerated the N400 effect. These data support the assumption of radical-based inputs proposed by the lexical constituent model. However, the phonetic consistency effects found at N170 and P200 cannot be reconciled with the current framework of the lexical constituent model. A possible revision will be discussed. (Contains 4 figures and 2 tables.)