Dip2a regulates stress susceptibility in the basolateral amygdala.

JOURNAL/nrgr/04.03/01300535-202506000-00025/figure1/v/2024-08-05T133530Z/r/image-tiff Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post-traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A (Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid-associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

Biofunctionalized dissolvable hydrogel microbeads enable efficient characterization of native protein complexes.

The characterization of protein complex is vital for unraveling biological mechanisms in various life processes. Despite advancements in biophysical tools, the capture of non-covalent complexes and deciphering of their biochemical composition continue to present challenges for low-input samples. Here we introduce SNAP-MS, a Stationary-phase-dissolvable Native Affinity Purification and Mass Spectrometric characterization strategy. It allows for highly efficient purification and characterization from inputs at the pico-mole level. SNAP-MS replaces traditional elution with matrix dissolving during the recovery of captured targets, enabling the use of high-affinity bait-target pairs and eliminates interstitial voids. The purified intact protein complexes are compatible with native MS, which provides structural information including stoichiometry, topology, and distribution of proteoforms, size variants and interaction states. An algorithm utilizes the bait as a charge remover and mass corrector significantly enhances the accuracy of analyzing heterogeneously glycosylated complexes. With a sample-to-data time as brief as 2 hours, SNAP-MS demonstrates considerable versatility in characterizing native complexes from biological samples, including blood samples.

Application of galactosylated albumin for targeted delivery of triptolide to suppress hepatocellular carcinoma progression through inhibiting de novo lipogenesis.

Hepatocellular carcinoma (HCC) remains the fourth leading cause of cancer-associated death globally with a lack of efficient therapy. The pathogenesis of HCC is a complex and multistep process, highly reliant on de novo lipogenesis, from which tumor cells can incorporate fatty acids to satisfy the necessary energy demands of rapid proliferation and provide survival advantages. Triptolide (TP) is a bioactive ingredient exhibiting potent abilities of anti-proliferation and lipid metabolism regulation, but its clinical application is constrained because of its toxicity and non-specific distribution. The present study has developed galactosylated bovine serum albumin nanoparticles loaded with TP (Gal-BSA-TP NPs) to alleviate systemic toxicity and increase tumor-targeting and antitumor efficacy. Furthermore, Gal-BSA-TP NPs could inhibit de novo lipogenesis via the p53-SREBP1C-FASN pathway to deprive the fuel supply of HCC, offering a specific strategy for HCC treatment. In general, this study provided a biocompatible delivery platform for targeted therapy for HCC from the perspective of de novo lipogenesis.

Epithelial-mesenchymal plasticity in cancer: signaling pathways and therapeutic targets.

Currently, cancer is still a leading cause of human death globally. Tumor deterioration comprises multiple events including metastasis, therapeutic resistance and immune evasion, all of which are tightly related to the phenotypic plasticity especially epithelial-mesenchymal plasticity (EMP). Tumor cells with EMP are manifest in three states as epithelial-mesenchymal transition (EMT), partial EMT, and mesenchymal-epithelial transition, which orchestrate the phenotypic switch and heterogeneity of tumor cells via transcriptional regulation and a series of signaling pathways, including transforming growth factor-ß, Wnt/ß-catenin, and Notch. However, due to the complicated nature of EMP, the diverse process of EMP is still not fully understood. In this review, we systematically conclude the biological background, regulating mechanisms of EMP as well as the role of EMP in therapy response. We also summarize a range of small molecule inhibitors, immune-related therapeutic approaches, and combination therapies that have been developed to target EMP for the outstanding role of EMP-driven tumor deterioration. Additionally, we explore the potential technique for EMP-based tumor mechanistic investigation and therapeutic research, which may burst vigorous prospects. Overall, we elucidate the multifaceted aspects of EMP in tumor progression and suggest a promising direction of cancer treatment based on targeting EMP.

Comprehensive Screening and Characterization of α-glucosidase Inhibitory Components in the Edible Medicinal Plant Pholidota cantonensis Rolfe Using UPLC-Q-TOF-MS/MS Analysis and Molecular Docking.

Pholidota cantonensis Rolfe is an edible medicinal plant in the genus Pholidota of the family Orchidaceae. This plant is used to prepare medicated food in China and has been reported to possess anti-α-glucosidase activity. To date, little is known about the active substances responsible for the observed anti-α-glucosidase activity. In the present study, we aimed to screen and characterize the α-glucosidase inhibitory fraction of P. cantonensis using ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) analysis and molecular docking. As a result, the 50% ethanol fraction obtained from D101 macroporous adsorption resin column chromatography (D50 fraction) had the highest total phenol content (353.83 ± 6.06 mg GAE/g) and the most prominent α-glucosidase inhibitory activity (IC50 = 30.01 ± 7.30 µg/mL). Forty-five compounds were identified from the D50 fraction by using UPLC-Q-TOF-MS/MS analysis. Molecular docking results showed that six main constituents, namely, crepidatin, 2,7-dihydroxy-4-methoxyl-9,10-dihydrophenylene, 4,4',5,6-tetrahydroxystilbene, 4,7-dihydroxy-2-methoxyl-9,10-dihydrophenylene, (-)-lariciresinol, and thunalbene, in the D50 fraction occupied the catalytic sites of α-glucosidase through strong hydrophobic interactions, hydrogen bonding, and other patterns. The binding energies were between - 29.95 and - 11.41 kJ/mol, indicating good binding between the tested compounds and α-glucosidase. The active ingredients responsible for the α-glucosidase inhibitory activity may include phenanthrenes, stilbenes, dibenzyls, and lignans. The D50 fraction has potential value for developing innovative drugs for the prevention and treatment of diabetes mellitus (DM) and is worthy of in-depth research.

Main-Group Metal-Nonmetal Dynamic Proton Bridges Enhance Ammonia Electrosynthesis.

The electrochemical nitrogen reduction reaction is a crucial process for the sustainable production of ammonia for energy and agriculture applications. However, the reaction's efficiency is highly dependent on the activation of the inert N≡N bond, which is hindered by the electron back-donation to the π* orbitals of the N≡N bond, resulting in low eNRR capacity. Herein, we report a main-group metal-non-metal (O-In-S) eNRR catalyst featuring a dynamic proton bridge, with In-S serving as the polarization pair and O functioning as the dynamic electron pool. In-situ spectroscopic analysis and theoretical calculations reveal that the In-S polarization pair acts as asymmetric dual-sites, polarizing the N≡N bond by concurrently back-donating electrons to both the πx* and πy* orbitals of N2, thereby overcoming the significant band gap limitations, while inhibiting the competitive hydrogen evolution reaction. Meanwhile, the O dynamic electron pool acts as a "repository" for electron storage and donation to the In-S polarization pair. As a result, the O-In-S dynamic proton bridge exhibits exceptional NH3 yield rates and Faradaic efficiencies (FEs) across a wide potential window of 0.3 V, with an optimal NH3 yield of 80.07 ± 4.25 µg h-1 mg-1 and an FE of 38.01 ± 2.02%, outperforming most previously reported catalysts.

PACAP ameliorates obesity-induced insulin resistance through FAIM/Rictor/AKT axis.

Obesity and obesity-related insulin resistance have been a research hotspot. Pituitary adenylate cyclase activating polypeptide (PACAP) has emerged as playing a significant role in energy metabolism, holding promising potential for attenuating insulin resistance. However, the precise mechanism is not fully understood. Palmitic acid and a high-fat diet (HFD) were used to establish insulin resistance model in Alpha mouse liver 12 cell line and C57BL/6 mice, respectively. Subsequently, we assessed the effects of PACAP both in vivo and in vitro. Lentivirus vectors were used to explore the signaling pathway through which PACAP may ameliorate insulin resistance. PACAP was found to selectively bind to the PACAP type I receptor receptor and ameliorate insulin resistance, which was characterized by increased glycogen synthesis and the suppression of gluconeogenesis in the insulin-resistant cell model and HFD-fed mice. These effects were linked to the activation of the Fas apoptotic inhibitory molecule/rapamycin-insensitive companion of mammalian target of rapamycin/RAC-alpha serine/threonine-protein kinase (FAIM/Rictor/AKT) axis. Furthermore, PACAP ameliorated insulin resistance by increasing solute carrier family 2, facilitated glucose transporter members 2/4 and inhibiting gluconeogenesis-related proteins glucose 6-phosphatase catalytic subunit 1 and phosphoenolpyruvate carboxykinase 2 expression. Meanwhile, the phosphorylation of hepatic AKT/glycogen synthase kinase 3ß was promoted both in vivo and in vitro by PACAP. Additionally, PACAP treatment decreased body weight, food intake and blood glucose levels in obese mice. Our study shows that PACAP ameliorated insulin resistance through the FAIM/Rictor/AKT axis, presenting it as a promising drug candidate for the treatment of obesity-related insulin resistance.

IKIP downregulates THBS1/FAK signaling to suppress migration and invasion by glioblastoma cells.

Background: Inhibitor of NF-κB kinase-interacting protein (IKIP) is known to promote proliferation of glioblastoma (GBM) cells, but how it affects migration and invasion by those cells is unclear. Methods: We compared levels of IKIP between glioma tissues and normal brain tissue in clinical samples and public databases. We examined the effects of IKIP overexpression and knockdown on the migration and invasion of GBM using transwell and wound healing assays, and we compared the transcriptomes under these different conditions to identify the molecular mechanisms involved. Results: Based on data from our clinical samples and from public databases, IKIP was overexpressed in GBM tumors, and its expression level correlated inversely with survival. IKIP overexpression in GBM cells inhibited migration and invasion in transwell and wound healing assays, whereas IKIP knockdown exerted the opposite effects. IKIP overexpression in GBM cells that were injected into mouse brain promoted tumor growth but inhibited tumor invasion of surrounding tissue. The effects of IKIP were associated with downregulation of THBS1 mRNA and concomitant inhibition of THBS1/FAK signaling. Conclusions: IKIP inhibits THBS1/FAK signaling to suppress migration and invasion of GBM cells.

Evolution and Genetic Differentiation of Pleurotus tuoliensis in Xinjiang, China, Based on Population Genomics.

Pleurotus tuoliensis is a unique species discovered in Xinjiang, China, which is recognized for its significant edible, medicinal, and economic value. It has been successfully incorporated into industrial production. Controversy has emerged concerning the evolution and environmental adaptability of this species due to inadequate interspecific ecology and molecular data. This study examines the germplasm resources of P. tuoliensis in the Xinjiang region. A total of 225 wild and cultivated strains of P. tuoliensis were gathered from seven representative regions. Phylogenetic analysis revealed that seven populations were notably segregated into three distinct groups, primarily attributed to environmental factors as the underlying cause for this differentiation. Population historical size data indicate that P. tuoliensis underwent two expansion events, one between 2 and 0.9 Mya (Miocene) and the other between 15 and 4 Mya (Early Pleistocene). The ancient climate fluctuations in the Xinjiang region might have contributed to the comparatively modest population size during the Pliocene epoch. Moreover, through the integration of biogeography and ancestral state reconstruction, it was determined that group C of P. tuoliensis emerged initially and subsequently dispersed to groups D and B, in that order. Subsequently, group D underwent independent evolution, whereas group B continued to diversify into groups A and EFG. The primary factor influencing this mode of transmission route is related to the geographical conditions and prevailing wind direction of each group. Subsequent research endeavors focused on assessing the domestication adaptability of P. tuoliensis to different substrates. It was found that the metabolic processes adapted during the domestication process were mainly related to energy metabolism, DNA repair, and environmental adaptability. Processes adapted to the host adaptability include responses to the host (meiosis, cell cycle, etc.) and stress in the growth environment (cysteine and methionine metabolism, sulfur metabolism, etc.). This study analyzed the systematic evolution and genetic differentiation of P. tuoliensis in Xinjiang. The identified loci and genes provide a theoretical basis for the subsequent improvement of germplasm resources and conducting molecular breeding.

Autophagy-mediated activation of the AIM2 inflammasome enhances M1 polarization of microglia and exacerbates retinal neovascularization.

Retinopathy of prematurity (ROP) is a retinal neovascularization (RNV) disease that is characterized by abnormal blood vessel development in the retina. Importantly, the etiology of ROP remains understudied. We re-analyzed previously published single-cell data and discovered a strong correlation between microglia and RNV diseases, particularly ROP. Subsequently, we found that reactive oxygen species reduced autophagy-dependent protein degradation of absent in melanoma 2 (AIM2) in hypoxic BV2 cells, leading to increased AIM2 protein accumulation. Furthermore, we engineered AIM2 knockout mice and observed that the RNV was significantly reduced compared to wild-type mice. In vitro vascular function assays also demonstrated diminished angiogenic capabilities following AIM2 knockdown in hypoxic BV2 cells. Mechanistically, AIM2 enhanced the M1-type polarization of microglia via the ASC/CASP1/IL-1ß pathway, resulting in RNV. Notably, the administration of recombinant protein IL-1ß exacerbated angiogenesis, while its inhibition ameliorated the condition. Taken together, our study provides a novel therapeutic target for ROP and offers insight into the interaction between pyroptosis and autophagy.

Modulating *OOH Adsorption on RuO2 for Efficient and Durable Acidic Water Oxidation Electrocatalysis.

Acidic water electrolysis is of considerable interest due to its higher current density operation and energy conversion efficiency, but its real industrial application is highly limited by the shortage of efficient, stable, and cost-effective acidic oxygen evolution reaction (OER) electrocatalysts. Here, an electrocatalyst consisting of Ni-implanted RuO2 supported is reported on α-MnO2 (MnO2/RuO2-Ni) that shows high activity and remarkable durability in acidic OER. Precisely, the MnO2/RuO2-Ni catalyst shows an overpotential of 198 mV at a current density of 10 mA cm-2 and can operate continuously and stably for 400 h (j = 10 mA cm-2) without any obvious attenuation of activity, making it one of the best-performing acid-stable OER catalysts. Experimental results, in conjunction with density functional theory calculations, demonstrate that the interface electron transfer effect from RuO2 to MnO2, further enhanced by Ni incorporation, effectively modulates the adsorption of OOH* and significantly reduces the overpotential, thereby enhancing catalytic activity and durability.

ZmPHR1 contributes to drought resistance by modulating phosphate homeostasis in maize.

As an essential macronutrient, phosphorus (P) is often a limiting nutrient because of its low availability and mobility in soils. Drought is a major environmental stress that reduces crop yield. How plants balance and combine P-starvation responses (PSRs) and drought resistance is unclear. In this study, we identified the transcription factor ZmPHR1 as a major regulator of PSRs that modulates phosphate (Pi) signaling and homeostasis. We found that maize zmphr1 mutants had reduced P concentration and were sensitive to Pi starvation, whereas ZmPHR1-OE lines displayed elevated Pi concentration and yields. In addition, 57% of PSR genes and nearly 70% of ZmPHR1-regulated PSR genes in leaves were transcriptionally responsive to drought. Under moderate and early drought conditions, the Pi concentration of maize decreased, and PSR genes were up-regulated before drought-responsive genes. The ZmPHR1-OE lines exhibited drought-resistant phenotypes and reduced stomatal apertures, whereas the opposite was true of the zmphr1 mutants. ZmPT7-OE lines and zmspx3 mutants, which had elevated Pi concentration, also exhibited drought resistance, but zmpt7 mutants were sensitive to drought. Our results suggest that ZmPHR1 plays a central role in integrating Pi and drought signals and that Pi homeostasis improves the ability of maize to combat drought.

Myelin debris phagocytosis in demyelinating disease.

Demyelinating diseases are often caused by a variety of triggers, including immune responses, viral infections, malnutrition, hypoxia, or genetic factors, all of which result in the loss of myelin in the nervous system. The accumulation of myelin debris at the lesion site leads to neuroinflammation and inhibits remyelination; therefore, it is crucial to promptly remove the myelin debris. Initially, Fc and complement receptors on cellular surfaces were the primary clearance receptors responsible for removing myelin debris. However, subsequent studies have unveiled the involvement of additional receptors, including Mac-2, TAM receptors, and the low-density lipoprotein receptor-related protein 1, in facilitating the removal process. In addition to microglia and macrophages, which serve as the primary effector cells in the disease phase, a variety of other cell types such as astrocytes, Schwann cells, and vascular endothelial cells have been demonstrated to engage in the phagocytosis of myelin debris. Furthermore, we have concluded that oligodendrocyte precursor cells, as myelination precursor cells, also exhibit this phagocytic capability. Moreover, our research group has innovatively identified the low-density lipoprotein receptor as a potential phagocytic receptor for myelin debris. In this article, we discuss the functional processes of various phagocytes in demyelinating diseases. We also highlight the alterations in signaling pathways triggered by phagocytosis, and provide a comprehensive overview of the various phagocytic receptors involved. Such insights are invaluable for pinpointing potential therapeutic strategies for the treatment of demyelinating diseases by targeting phagocytosis.

Volatilomics of Cabernet Sauvignon grapes and sensory perception of wines are affected by canopy side in vineyards with different row orientations.

This study aimed to clarify how microclimate diversity altered volatilomics in Cabernet Sauvignon grapes and wines. Four row-oriented vineyards were selected, and metabolites of grapes and wines were determined from separate canopy sides. Results showed that shaded sides received 59% of the solar radiation and experienced 55% of the high-temperature days compared to the exposed sides on average. Grape primary metabolites were slightly affected by the canopy side. Herbaceous aromas were consistently more abundant in grapes and wines from shaded clusters. Heat-stressed canopy sides accelerated terpenoid loss and increased norisoprenoid levels in grapes, while ß-damascenone in north-side wines was 13%-32% higher than that in south-side wines of the east-west vineyard. The northeast-southwest vineyard showed the most notable variation in taste and aroma sensory scores, with four parameters significantly different. There were 32 aroma series identified in wines, and banana, pineapple, and strawberry odors were highly correlated with aroma sensory score.

A novel one-stepped synthesized Schiff-base fluorescence probe for specific recognition of zinc ions with highly sensitive and its application in living cells.

Fluorescent turn-on receptors are extensively employed for the detection of Zn ions contamination in the environment due to its simplicity, convenience and portability. However, developing highly sensitive and cell-imageable fluorescent turn-on probe for the recognition of Zn ions in living organisms remains a significant challenge. Herein, we have successfully synthesized a novel Schiff base probe (H2L) with a significant fluorescence turn-on response (Zn ions) by one-step synthetic method. In this work, H2L exhibited high sensitivity to Zn2+ ions upon interaction with various common metal ions in HEPES buffer solution. Its detection limit is 1.87 × 10-7 M, which is lower than the requirement of Environmental Protection Agency (EPA) and World Health Organization (WHO) guidelines. The fluorescence titration and Job's plot analysis suggested a 1:1 binding ratio between the probe and Zn ion, and the single-crystal structures obtained further confirmed this inference. In addition, the fluorescent sensor demonstrated recyclability, maintaining its fluorescence intensity for up to 6 cycles without significant decrease, which holds promise for future investigations on reversible fluorescent chemosensors. Notably, fluorescence imaging experiments demonstrated that H2L could be successfully used for the detection of Zn2+ in live cells.

A Halogen-Bonded Fluorescent Molecular Photoswitch: Transition from 3D Cubic Lattice to 1D Helical Superstructure for Polarization Inversion of Circularly Polarized Luminescence.

The fabrication of materials that can switch between circularly polarized luminescence (CPL) signals is both essential and challenging. Here, two new halogen-bonded fluorescent molecular photoswitches, namely, HB-switch 1 and HB-switch 2, containing α-cyano-substituted diarylethene compounds with different end groups were developed. Upon exposure to specific UV or visible light wavelengths, they exhibited controllable and reversible Z/E photoisomerization. When these switches were integrated into blue-phase liquid crystals (BPLCs), the temperature range of BP significantly expanded. Notably, the BP system incorporating HB-switch 1 exclusively achieved reversible polarization inversion of CPL signals under irradiation with specific UV/Visible light and during cooling/heating. The photo/thermal dual-response behavior of the CPL signals can be attributed to the phase transition from a high-symmetry 3D BP Icubic lattice to a low-symmetry 1D helical superstructure induced by the Z/E photoisomerization of HB-switch 1 and temperature changes. This study underscores the significance of employing halogen-bond assembly strategies to design materials with switchable CPL signals, opening new possibilities for CPL-active systems.

Diagnostic performance of mpox virus (MPXV) real-time PCR assays: multicenter assessment and extended sensitivity analysis.

PURPOSE: To comprehensively investigate the diagnostic performance of routinely used assays in MPXV testing, the National Center of Clinical Laboratories in China conducted a nationwide external quality assessment (EQA) scheme and an evaluated nine assays used by ≥ 5 laboratories in the EQA. METHODS: MPXV virus-like particles with 2700, 900 and 300 copies/mL were distributed to 195 EQA laboratories. For extended analysis, triple-diluted samples from 9000 to 4.12 copies/mL were repeated 20 times using the assays employed by ≥ 5 laboratories. The diagnostic performance was assessed by analyzing EQA data and calculating the limits of detection (LODs). RESULTS: The performance was competent in 87.69% (171/195) of the participants and 87.94% (175/199) of the datasets. The positive percentage agreements (PPAs) were greater than 99% for samples at 2700 and 900 copies/mL, and 95.60% (761/796) for samples at 300 copies/mL. The calculated LODs for the two clades ranged from 228.44 to 924.31 copies/mL and were greater than the LODs specified by the respective kits. EasyDiagnosis had the lowest calculated LODs and showed superior performance in EQA, whereas BioGerm and Sansure, with higher calculated LODs, did not perform well in EQA. CONCLUSION: This study provides valuable information from the EQA data and evaluation of the diagnostic performance of MPXV detection assays. It also provided insights into reagent optimization and enabled prompt public health interventions for the outbreak.

The responses and tolerance of photosynthetic system in Chlorella vulgaris to the pharmaceutical pollutant carbamazepine.

Screening for sensitive toxicological indicators and understanding algal tolerance to pharmaceutical contaminants (PhCs) are essential for assessing PhCs risk and their removal by microalgae. Carbamazepine (CBZ) showed adverse effects on microalgae, but the specific toxicity mechanisms on the most sensitive algal photosynthetic system (PS) remain limited. This study delved into the impact of CBZ exposure on the growth, cell viability, pigment content, and PS of Chlorella vulgaris. The findings revealed a notable inhibition of C. vulgaris growth by CBZ, with an IC50 value of 27.2 mg/L at 96 h. CBZ exposure induced algal membrane damage and cell viability. Intriguingly, CBZ drastically diminished intracellular pigment levels, notably showing "low promotion and high inhibition" of chlorophyll b (Chl b) by 72 h. Moreover, the study identified a decreased number of active reaction centers (RCs) within algal PSII alongside inhibited electron transport from QA to QB on the PSII receptor side, leading to PSII disruption. As an adaptive response to CBZ stress, C. vulgaris stimulated its Chl b synthesis, increased non-photochemical quenching (NPQ), and adapted its tolerance to bright light. Additionally, the alga attempted to compensate for the CBZ-induced reduction in electron transfer efficiency at the PSII receptor side and light energy utilization by increasing its electron transfer from downstream. Principal component analysis (PCA) further verified that the parameters on non-photochemical dissipation, electron transport, and integrative performance were the most sensitive algal toxicological indicators for CBZ exposure, and algal PS has energy protection capability through negative feedback regulation. However, prolonged exposure to high doses of CBZ will eventually result in permanent damage to the algal PS. Hence, attention should be paid to the concentration of CBZ in the effluent and the exposure time, while methods to mitigate algal photodamage should be appropriately sought for algal treatment of dense effluents.

A Surface Electromyography (sEMG) System Applied for Grip Force Monitoring.

Muscles play an indispensable role in human life. Surface electromyography (sEMG), as a non-invasive method, is crucial for monitoring muscle status. It is characterized by its real-time, portable nature and is extensively utilized in sports and rehabilitation sciences. This study proposed a wireless acquisition system based on multi-channel sEMG for objective monitoring of grip force. The system consists of an sEMG acquisition module containing four-channel discrete terminals and a host computer receiver module, using Bluetooth wireless transmission. The system is portable, wearable, low-cost, and easy to operate. Leveraging the system, an experiment for grip force prediction was designed, employing the bald eagle search (BES) algorithm to enhance the Random Forest (RF) algorithm. This approach established a grip force prediction model based on dual-channel sEMG signals. As tested, the performance of acquisition terminal proceeded as follows: the gain was up to 1125 times, and the common mode rejection ratio (CMRR) remained high in the sEMG signal band range (96.94 dB (100 Hz), 84.12 dB (500 Hz)), while the performance of the grip force prediction algorithm had an R2 of 0.9215, an MAE of 1.0637, and an MSE of 1.7479. The proposed system demonstrates excellent performance in real-time signal acquisition and grip force prediction, proving to be an effective muscle status monitoring tool for rehabilitation, training, disease condition surveillance and scientific fitness applications.

The Relationship Between Social Isolation and Cognitive Frailty Among Community-Dwelling Older Adults: The Mediating Role of Depressive Symptoms.

Purpose: Social isolation and depression have an impact on cognitive frailty. However, the underlying mechanisms between these variables have not been well defined. This study aims to investigate the mediating role of depressive symptoms in the association between social isolation and cognitive frailty among older adults in China. Methods: From Mar 2023 to Aug 2023, a cross-sectional study was conducted with 496 community-dwelling older adults aged ≥60 years in Nanjing, Jiangsu Province, China. Demographic information was collected using the General Information Questionnaire. The Lubben Social Network Scale-6 (LSNS-6), Geriatric Depression Scale 15-item (GDS-15), Montreal Cognitive Assessment (MoCA), Clinical Dementia Rating (CDR), and FRAIL scale were used for the questionnaire survey. Multiple linear regression and binary logistic regression were utilized to explore the associations among social isolation, depressive symptoms, and cognitive frailty, and Bootstrap analysis was used to explore the mediating role of depressive symptoms in social isolation and cognitive frailty. Results: Linear regression results revealed that social isolation was positively associated with depressive symptoms (ß = 0.873, p < 0.001). Logistic regression analysis showed that social isolation (OR = 1.769, 95% CI = 1.018~3.075) and depressive symptoms (OR = 1.227, 95% CI = 1.108~1.357) were significantly associated with cognitive frailty. Mediation analysis demonstrated that depressive symptoms significantly mediated the relationship between social isolation and cognitive frailty, with an indirect effect of 0.027 (95% CI = 0.003~0.051), and the mediating effect accounted for 23.6% of the total effect. Conclusion: Social isolation is associated with cognitive frailty in community-dwelling older adults, and depressive symptoms partially mediate the effect between social isolation and cognitive frailty. Active promotion of social integration among older individuals is recommended to enhance their mental health, reduce the incidence of cognitive frailty, and foster active aging.