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1.
bioRxiv ; 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39229176

ABSTRACT

Cognitive abilities of primates, including humans, continue to improve through adolescence 1,2. While a range of changes in brain structure and connectivity have been documented 3,4, how they affect neuronal activity that ultimately determines performance of cognitive functions remains unknown. Here, we conducted a multilevel longitudinal study of monkey adolescent neurocognitive development. The developmental trajectory of neural activity in the prefrontal cortex accounted remarkably well for working memory improvements. While complex aspects of activity changed progressively during adolescence, such as the rotation of stimulus representation in multidimensional neuronal space, which has been implicated in cognitive flexibility, even simpler attributes, such as the baseline firing rate in the period preceding a stimulus appearance had predictive power over behavior. Unexpectedly, decreases in brain volume and thickness, which are widely thought to underlie cognitive changes in humans 5 did not predict well the trajectory of neural activity or cognitive performance changes. Whole brain cortical volume in particular, exhibited an increase and reached a local maximum in late adolescence, at a time of rapid behavioral improvement. Maturation of long-distance white matter tracts linking the frontal lobe with areas of the association cortex and subcortical regions best predicted changes in neuronal activity and behavior. Our results provide evidence that optimization of neural activity depending on widely distributed circuitry effects cognitive development in adolescence.

2.
Nanomaterials (Basel) ; 14(17)2024 Aug 31.
Article in English | MEDLINE | ID: mdl-39269087

ABSTRACT

Silver nanoparticles (Ag NPs) have accumulated significant interest due to their exceptional physicochemical properties and remarkable applications in biomedicine, electronics, and catalysis sensing. This comprehensive review provides an in-depth study of synthetic approaches such as biological synthesis, chemical synthesis, and physical synthesis with a detailed overview of their sub-methodologies, highlighting advantages and disadvantages. Additionally, structural properties affected by synthesis methods are discussed in detail by examining the dimensions and surface morphology. The review explores the distinctive properties of Ag NPs, including optical, electrical, catalytic, and antimicrobial properties, which render them beneficial for a range of applications. Furthermore, this review describes the diverse applications in several fields, such as medicine, environmental science, electronics, and optoelectronics. However, with numerous applications, several kinds of issues still exist. Future attempts need to address difficulties regarding synthetic techniques, environmental friendliness, and affordability. In order to ensure the secure utilization of Ag NPs, it is necessary to establish sustainability in synthetic techniques and eco-friendly production methods. This review aims to give a comprehensive overview of the synthesis, structural analysis, properties, and multifaceted applications of Ag NPs.

3.
Plant Physiol Biochem ; 215: 109011, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39128403

ABSTRACT

Phosphate deficiency and drought are significant environmental constraints that impact both the productivity and quality of wheat. The interaction between phosphorus and water facilitates their mutual absorption processes in plants. Under conditions of both phosphorus deficiency and drought stress, we observed a significant upregulation in the expression of wheat MYB-CC transcription factors through the transcriptome analysis. 52 TaMYB-CC genes in wheat were identified and analyzed their evolutionary relationships, structures, and expression patterns. The TaMYB-CC5 gene exhibited specific expression in roots and demonstrated significant upregulation under phosphorus deficiency and drought stress compared to other TaMYB-CC genes. The overexpression of TaMYB-CC5A in Arabidopsis resulted in a significant increase of root length under stress conditions, thereby enhancing tolerance to phosphate starvation and drought stress. The wheat lines with silenced TaMYB-CC5 genes exhibited reduced root length under stress conditions and increased sensitivity to phosphate deficiency and drought stress. In addition, silencing the TaMYB-CC5 genes resulted in altered phosphorus content in leaves but did not lead to a reduction in phosphorus content in roots. Enrichment analysis the co-expression genes of TaMYB-CC5 transcription factors, we found the zinc-induced facilitator-like (ZIFL) genes were prominent associated with TaMYB-CC5 gene. The TaZIFL1, TaZIFL2, and TaZIFL5 genes were verified specifically expressed in roots and regulated by TaMYB-CC5 transcript factor. Our study reveals the pivotal role of the TaMYB-CC5 gene in regulating TaZIFL genes, which is crucial for maintaining normal root growth under phosphorus deficiency and drought stress, thereby enhanced resistance to these abiotic stresses in wheat.


Subject(s)
Droughts , Gene Expression Regulation, Plant , Phosphorus , Plant Proteins , Plant Roots , Triticum , Triticum/genetics , Triticum/metabolism , Triticum/growth & development , Phosphorus/deficiency , Phosphorus/metabolism , Plant Roots/metabolism , Plant Roots/genetics , Plant Roots/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Stress, Physiological/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis/physiology , Plants, Genetically Modified
4.
Anal Chem ; 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39134457

ABSTRACT

Circulating tumor DNA (ctDNA) is a critical biomarker for early tumor detection. However, accurately quantifying low-abundance ctDNA in human serum remains a significant challenge. To address this challenge, we introduce a bimodal biosensor tailored for detecting the epidermal growth factor receptor (EGFR) mutation L858R in specific nonsmall cell lung cancer (NSCLC) patients. This biosensor utilizes dual CRISPR-Cas12a systems to quantify the target via fluorescence and electrochemical signals. In our system, the EGFR L858R exhibits resistance to digestion by the restriction enzyme MscI, which activates the first CRISPR-Cas12a protein and inhibits the binding of magnetic beads with fluorescein (FAM)-labeled hybridization chain reaction (HCR) products, thereby reducing the fluorescence signal. This activation also inhibits the cleavage activity of the second CRISPR-Cas12a protein, allowing the electrode to sustain a higher electrochemical signal from nanomaterials. The wild-type EGFR (wt EGFR) produces the opposite effect. Consequently, the concentration of EGFR L858R can be accurately quantified and verified using both fluorescence and electrochemical signals. The biosensor offers a dynamic detection ranging from 10 fM to 1 µM, with a detection limit of 372 aM. It demonstrates excellent specificity, reproducibility, stability, and recovery rates. Moreover, the sensor's enhanced analytical sensitivity highlights its critical role in biosensing applications and early disease diagnosis.

5.
Nat Commun ; 15(1): 6694, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39107317

ABSTRACT

Prefrontal cortical activity represents stimuli in working memory tasks in a low-dimensional manifold that transforms over the course of a trial. Such transformations reflect specific cognitive operations, so that, for example, the rotation of stimulus representations is thought to reduce interference by distractor stimuli. Here we show that rotations occur in the low-dimensional activity space of prefrontal neurons in naïve male monkeys (Macaca mulatta), while passively viewing familiar stimuli. Moreover, some aspects of these rotations remain remarkably unchanged after training to perform working memory tasks. Significant training effects are still present in population dynamics, which further distinguish correct and error trials during task execution. Our results reveal automatic functions of prefrontal neural circuits allow transformations that may aid cognitive flexibility.


Subject(s)
Macaca mulatta , Memory, Short-Term , Neurons , Prefrontal Cortex , Animals , Prefrontal Cortex/physiology , Prefrontal Cortex/cytology , Male , Neurons/physiology , Memory, Short-Term/physiology , Cognition/physiology , Photic Stimulation
6.
Talanta ; 279: 126665, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39116728

ABSTRACT

Mucin 1 (MUC1) is frequently overexpressed in various cancers and is essential for early cancer detection. Current methods to detect MUC1 are expensive, time-consuming, and require skilled personnel. Therefore, developing a simple, sensitive, highly selective MUC1 detection sensor is necessary. In this study, we proposed a novel "signal-on-off" strategy that, in the presence of MUC1, synergistically integrates catalytic hairpin assembly (CHA) with DNA tetrahedron (Td)-based nonlinear hybridization chain reaction (HCR) to enhance the immobilization of electrochemically active methylene blue (MB) on magnetic nanoparticles (MNP), marking the MB signal "on". Concurrently, the activation of CRISPR-Cas12a by isothermal amplification products triggers the cleavage of single-stranded DNA (ssDNA) at the electrode surface, resulting in a reduction of MgAl-LDH@Fc-AuFe-MIL-101 (containing ferrocene, Fc) on the electrode, presenting the "signal-off" state. Both MB and MgAl-LDH@Fc-AuFe-MIL-101 electrochemical signals were measured and analyzed. Assay parameters were optimized, and sensitivity, stability, and linear range were assessed. Across a concentration spectrum of MUC1 spanning from 10 fg/mL to 100 ng/mL, the MB and MgAl-LDH@Fc-AuFe-MIL-101 signals were calibrated with each other, demonstrating a "signal-on-off" dual electrochemical signaling pattern. This allows for the precise and quantitative detection of MUC1 in clinical samples, offering significant potential for medical diagnosis.


Subject(s)
Biosensing Techniques , CRISPR-Cas Systems , Electrochemical Techniques , Mucin-1 , Nucleic Acid Hybridization , Mucin-1/analysis , Mucin-1/genetics , Electrochemical Techniques/methods , Humans , Biosensing Techniques/methods , CRISPR-Cas Systems/genetics , Methylene Blue/chemistry , Magnetite Nanoparticles/chemistry , DNA, Single-Stranded/chemistry , DNA, Single-Stranded/genetics , Electrodes , Limit of Detection , Gold/chemistry
7.
Molecules ; 29(14)2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39064899

ABSTRACT

Nickel-based catalysts are regarded as the most excellent urea oxidation reaction (UOR) catalysts in alkaline media. Whatever kind of nickel-based catalysts is utilized to catalyze UOR, it is widely believed that the in situ-formed Ni3+ moieties are the true active sites and the as-utilized nickel-based catalysts just serve as pre-catalysts. Digging the pre-catalyst effect on the activity of Ni3+ moieties helps to better design nickel-based catalysts. Herein, five different anions of OH-, CO32-, SiO32-, MoO42-, and WO42- were used to bond with Ni2+ to fabricate the pre-catalysts ß-Ni(OH)2, Ni-CO3, Ni-SiO3, Ni-MoO4, and Ni-WO4. It is found that the true active sites of the five as-fabricated catalysts are the same in situ-formed Ni3+ moieties and the five as-fabricated catalysts demonstrate different UOR activity. Although the as-synthesized five catalysts just serve as the pre-catalysts, they determine the quantity of active sites and activity per active site, thus determining the catalytic activity of the catalysts. Among the five catalysts, the amorphous nickel tungstate exhibits the most superior activity per active site and can catalyze UOR to reach 158.10 mA·cm-2 at 1.6 V, exceeding the majority of catalysts. This work makes for a deeper understanding of the pre-catalyst effect on UOR activity and helps to better design nickel-based UOR catalysts.

8.
Am J Transl Res ; 16(6): 2501-2508, 2024.
Article in English | MEDLINE | ID: mdl-39006257

ABSTRACT

OBJECTIVES: To assess the efficacy, safety, and impact on serum cytokines of olopatadine hydrochloride (OLP) combined with desloratadine citrate disodium (DES) in treating urticaria. METHODS: We retrospectively analyzed 114 urticaria patients treated at the Affiliated Hospital of Xinyang Vocational and Technical College from March 2020 to March 2023. The control group (55 patients) received DES, while the research group (59 patients) received OLP+DES combination therapy. We compared efficacy, safety (including epigastric pain, dry mouth, lethargy, dizziness, and fatigue), changes in serum cytokines (interleukin [IL]-2, IL-4, and interferon [IFN]-γ), symptom resolution (wheal number, wheal size, and itching degree), and 3-month recurrence rates. A univariate analysis was also conducted to identify factors influencing urticaria recurrence. RESULTS: The research group exhibited a significantly higher overall efficacy rate, lower incidence of adverse events, and reduced recurrence rates at 3 months (all P<0.05) compared to the control group. Post-treatment, the research group showed significant increases in IL-2 and IFN-γ levels and reductions in IL-4 levels, wheal number, wheal size, and itching degree (all P<0.05). Factors such as history of drinking/smoking, IL-2 levels, and treatment method were associated with urticaria recurrence (all P<0.05). CONCLUSIONS: The combination of OLP and DES is an effective and safe treatment option for urticaria, significantly improving serum cytokine profiles, alleviating symptoms, and reducing recurrence risk.

9.
Cancer Lett ; 598: 217094, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-38945204

ABSTRACT

Recent therapeutic strategies for the treatment of triple-negative breast cancer (TNBC) have shifted the focus from vascular growth factors to endothelial cell metabolism. This study highlights the underexplored therapeutic potential of peri-tumoral electroacupuncture, a globally accepted non-pharmacological intervention for TNBC, and molecular mechanisms. Our study showed that peri-tumoral electroacupuncture effectively reduced the density of microvasculature and enhanced vascular functionality in 4T1 breast cancer xenografts, with optimal effects on day 3 post-acupuncture. The timely integration of peri-tumoral electroacupuncture amplified the anti-tumor efficacy of paclitaxel. Multi-omics analysis revealed Glyoxalase 1 (Glo1) and the associated methylglyoxal-glycolytic pathway as key mediators of electroacupuncture-induced vascular normalization. Peri-tumoral electroacupuncture notably reduced Glo1 expression in the endothelial cells of 4T1 xenografts. Using an in vivo matrigel plug angiogenesis assay, we demonstrated that either Glo1 knockdown or electroacupuncture inhibited angiogenesis. In contrast, Glo1 overexpression increased blood vessel formation. In vitro pharmacological inhibition and genetic knockdown of Glo1 in human umbilical vein endothelial cells inhibited proliferation and promoted apoptosis via downregulating the methylglyoxal-glycolytic pathway. The study using the Glo1-silenced zebrafish model further supported the role of Glo1 in vascular development. This study underscores the pivotal role of Glo1 in peri-tumoral electroacupuncture, spotlighting a promising avenue for enhancing vascular normalization and improving TNBC treatment outcomes.


Subject(s)
Electroacupuncture , Glycolysis , Lactoylglutathione Lyase , Neovascularization, Pathologic , Triple Negative Breast Neoplasms , Animals , Female , Humans , Mice , Cell Line, Tumor , Cell Proliferation , Electroacupuncture/methods , Endothelial Cells/metabolism , Human Umbilical Vein Endothelial Cells , Lactoylglutathione Lyase/metabolism , Lactoylglutathione Lyase/genetics , Mice, Inbred BALB C , Neovascularization, Pathologic/metabolism , Paclitaxel/pharmacology , Pyruvaldehyde/metabolism , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Triple Negative Breast Neoplasms/therapy , Xenograft Model Antitumor Assays , Zebrafish
10.
Int J Mol Sci ; 25(11)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38892338

ABSTRACT

The elongation of the mesocotyl plays an important role in the emergence of maize deep-sowing seeds. This study was designed to explore the function of exogenous salicylic acid (SA) and 6-benzylaminopurine (6-BA) in the growth of the maize mesocotyl and to examine its regulatory network. The results showed that the addition of 0.25 mmol/L exogenous SA promoted the elongation of maize mesocotyls under both 3 cm and 15 cm deep-sowing conditions. Conversely, the addition of 10 mg/L exogenous 6-BA inhibited the elongation of maize mesocotyls. Interestingly, the combined treatment of exogenous SA-6-BA also inhibited the elongation of maize mesocotyls. The longitudinal elongation of mesocotyl cells was the main reason affecting the elongation of maize mesocotyls. Transcriptome analysis showed that exogenous SA and 6-BA may interact in the hormone signaling regulatory network of mesocotyl elongation. The differential expression of genes related to auxin (IAA), jasmonic acid (JA), brassinosteroid (BR), cytokinin (CTK) and SA signaling pathways may be related to the regulation of exogenous SA and 6-BA on the growth of mesocotyls. In addition, five candidate genes that may regulate the length of mesocotyls were screened by Weighted Gene Co-Expression Network Analysis (WGCNA). These genes may be involved in the growth of maize mesocotyls through auxin-activated signaling pathways, transmembrane transport, methylation and redox processes. The results enhance our understanding of the plant hormone regulation of mesocotyl growth, which will help to further explore and identify the key genes affecting mesocotyl growth in plant hormone signaling regulatory networks.


Subject(s)
Benzyl Compounds , Gene Expression Regulation, Plant , Plant Growth Regulators , Purines , Salicylic Acid , Zea mays , Zea mays/growth & development , Zea mays/drug effects , Zea mays/genetics , Zea mays/metabolism , Salicylic Acid/pharmacology , Salicylic Acid/metabolism , Purines/pharmacology , Benzyl Compounds/pharmacology , Gene Expression Regulation, Plant/drug effects , Plant Growth Regulators/pharmacology , Plant Growth Regulators/metabolism , Oxylipins/pharmacology , Cytokinins/metabolism , Cytokinins/pharmacology , Seeds/drug effects , Seeds/growth & development , Seeds/genetics , Gene Expression Profiling , Signal Transduction/drug effects , Indoleacetic Acids/pharmacology , Indoleacetic Acids/metabolism , Cyclopentanes/pharmacology
11.
Neurochem Res ; 49(7): 1806-1822, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38713437

ABSTRACT

Ischemic stroke presents a global health challenge, necessitating an in-depth comprehension of its pathophysiology and therapeutic strategies. While reperfusion therapy salvages brain tissue, it also triggers detrimental cerebral ischemia-reperfusion injury (CIRI). In our investigation, we observed the activation of nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy in an oxygen-glucose deprivation/reoxygenation (OGD/R) model using HT22 cells (P < 0.05). This activation contributed to oxidative stress (P < 0.05), enhanced autophagy (P < 0.05) and cell death (P < 0.05) during CIRI. Silencing NCOA4 effectively mitigated OGD/R-induced damage (P < 0.05). These findings suggested that targeting NCOA4-mediated ferritinophagy held promise for preventing and treating CIRI. Subsequently, we substantiated the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway effectively regulated the NCOA4-mediated ferritinophagy, by applying the cGAS inhibitor RU.521 and performing NCOA4 overexpression (P < 0.05). Suppressing the cGAS-STING pathway efficiently curtailed ferritinophagy (P < 0.05), oxidative stress (P < 0.05), and cell damage (P < 0.05) of CIRI, while NCOA4 overexpression could alleviate this effect (P < 0.05). Finally, we elucidated the specific molecular mechanism underlying the protective effect of the iron chelator deferoxamine (DFO) on CIRI. Our findings revealed that DFO alleviated hypoxia-reoxygenation injury in HT22 cells through inhibiting NCOA4-mediated ferritinophagy and reducing ferrous ion levels (P < 0.05). However, the protective effects of DFO were counteracted by cGAS overexpression (P < 0.05). In summary, our results indicated that the activation of the cGAS-STING pathway intensified cerebral damage during CIRI by inducing NCOA4-mediated ferritinophagy. Administering the iron chelator DFO effectively attenuated NCOA4-induced ferritinophagy, thereby alleviating CIRI. Nevertheless, the role of the cGAS-STING pathway in CIRI regulation likely involves intricate mechanisms, necessitating further validation in subsequent investigations.


Subject(s)
Autophagy , Ferritins , Nuclear Receptor Coactivators , Reperfusion Injury , Nuclear Receptor Coactivators/metabolism , Animals , Reperfusion Injury/metabolism , Reperfusion Injury/drug therapy , Ferritins/metabolism , Mice , Autophagy/drug effects , Autophagy/physiology , Cell Line , Oxidative Stress/drug effects , Oxidative Stress/physiology , Brain Ischemia/metabolism , Brain Ischemia/drug therapy
12.
Toxicol Lett ; 397: 34-41, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38734219

ABSTRACT

Humantenmine, koumine, and gelsemine are three indole alkaloids found in the highly toxic plant Gelsemium. Humantenmine was the most toxic, followed by gelsemine and koumine. The aim of this study was to investigate and analyze the effects of these three substances on tissue distribution and toxicity in mice pretreated with the Cytochrome P450 3A4 (CYP3A4) inducer ketoconazole and the inhibitor rifampicin. The in vivo test results showed that the three alkaloids were absorbed rapidly and had the ability to penetrate the blood-brain barrier. At 5 min after intraperitoneal injection, the three alkaloids were widely distributed in various tissues and organs, the spleen and pancreas were the most distributed, and the content of all tissues decreased significantly at 20 min. Induction or inhibition of CYP3A4 in vivo can regulate the distribution and elimination effects of the three alkaloids in various tissues and organs. Additionally, induction of CYP3A4 can reduce the toxicity of humantenmine, and vice versa. Changes in CYP3A4 levels may account for the difference in toxicity of humantenmine. These findings provide a reliable and detailed dataset for drug interactions, tissue distribution, and toxicity studies of Gelsemium alkaloids.


Subject(s)
Cytochrome P-450 CYP3A , Gelsemium , Indole Alkaloids , Animals , Gelsemium/chemistry , Cytochrome P-450 CYP3A/metabolism , Indole Alkaloids/toxicity , Tissue Distribution , Male , Mice , Ketoconazole/toxicity , Ketoconazole/pharmacology , Cytochrome P-450 CYP3A Inducers/pharmacology , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/drug effects , Cytochrome P-450 CYP3A Inhibitors/pharmacology , Alkaloids
13.
Sci Rep ; 14(1): 9711, 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38678041

ABSTRACT

Based on the system dynamics theory, this paper establishes an environmental mass event evolution model and explores the evolution law of mass events caused by environmental problems. From a methodological point of view, the mixed-strategy evolutionary game principle and dynamic punishment measures are combined, and simulation analysis is carried out by Anylogic software, and the results show that there is no stable evolutionary equilibrium solution for the two sides of the game in the traditional asymmetric mixed-strategy game model, and after adjusting the game payoff matrix and incorporating the dynamic punishment strategy, stable evolutionary equilibrium solutions appear in the evolutionary game model, and the system begins to tend to be stabilized. The process and conclusions of the simulation experiment provide methodological reference and theoretical support for the analysis of the evolution of environmental mass events.

14.
J Neurosci ; 44(23)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38641409

ABSTRACT

The behavioral and neural effects of the endogenous release of acetylcholine following stimulation of the nucleus basalis (NB) of Meynert have been recently examined in two male monkeys (Qi et al., 2021). Counterintuitively, NB stimulation enhanced behavioral performance while broadening neural tuning in the prefrontal cortex (PFC). The mechanism by which a weaker mnemonic neural code could lead to better performance remains unclear. Here, we show that increased neural excitability in a simple continuous bump attractor model can induce broader neural tuning and decrease bump diffusion, provided neural rates are saturated. Increased memory precision in the model overrides memory accuracy, improving overall task performance. Moreover, we show that bump attractor dynamics can account for the nonuniform impact of neuromodulation on distractibility, depending on distractor distance from the target. Finally, we delve into the conditions under which bump attractor tuning and diffusion balance in biologically plausible heterogeneous network models. In these discrete bump attractor networks, we show that reducing spatial correlations or enhancing excitatory transmission can improve memory precision. Altogether, we provide a mechanistic understanding of how cholinergic neuromodulation controls spatial working memory through perturbed attractor dynamics in the PFC.


Subject(s)
Memory, Short-Term , Models, Neurological , Prefrontal Cortex , Spatial Memory , Prefrontal Cortex/physiology , Memory, Short-Term/physiology , Spatial Memory/physiology , Animals , Acetylcholine/metabolism , Male , Cholinergic Neurons/physiology , Cholinergic Neurons/drug effects , Basal Nucleus of Meynert/physiology
15.
Mater Horiz ; 11(8): 1975-1988, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38353589

ABSTRACT

Flexible tactile sensors have become important as essential tools for facilitating human and object interactions. However, the materials utilized for the electrodes of capacitive tactile sensors often cannot simultaneously exhibit high conductivity, low modulus, and strong adhesiveness. This limitation restricts their application on flexible interfaces and results in device failure due to mechanical mismatch. Herein, we report an ultra-low modulus, highly conductive, and adhesive elastomer and utilize it to fabricate a microstructure-coupled multifunctional flexible tactile sensor. We prepare a supramolecular conductive composite film (SCCF) as the electrode of the tactile sensor using a supramolecular deep eutectic solvent, polyvinyl alcohol (PVA) solution, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), and MXene suspension. We employ a polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP) film containing 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM:TFSI) as the dielectric layer to fabricate capacitive sensors with an electrical double layer structure. Furthermore, we enhance the performance of the device by incorporating coupled pyramid and dome microstructures, which endow the sensor with multi-directional force detection. Our SCCF exhibits extremely high conductivity (reaching 710 S cm-1), ultra-low modulus (0.8 MPa), and excellent interface adhesion strength (>120 J m-2). Additionally, due to the outstanding conductivity and unique structure of the SCCF, it possesses remarkable electromagnetic shielding ability (>50 dB). Moreover, our device demonstrates a high sensitivity of up to 1756 kPa-1 and a wide working range reaching 400 kPa, combining these attributes with the requirements of an ultra-soft human-machine interface to ensure optimal contact between the sensor and interface materials. This innovative and flexible tactile sensor holds great promise and potential for addressing various and complex demands of human-machine interaction.

16.
bioRxiv ; 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38293215

ABSTRACT

The behavioral and neural effects of the endogenous release of acetylcholine following stimulation of the Nucleus Basalis of Meynert (NB) have been recently examined (Qi et al. 2021). Counterintuitively, NB stimulation enhanced behavioral performance while broadening neural tuning in the prefrontal cortex (PFC). The mechanism by which a weaker mnemonic neural code could lead to better performance remains unclear. Here, we show that increased neural excitability in a simple continuous bump attractor model can induce broader neural tuning and decrease bump diffusion, provided neural rates are saturated. Increased memory precision in the model overrides memory accuracy, improving overall task performance. Moreover, we show that bump attractor dynamics can account for the nonuniform impact of neuromodulation on distractibility, depending on distractor distance from the target. Finally, we delve into the conditions under which bump attractor tuning and diffusion balance in biologically plausible heterogeneous network models. In these discrete bump attractor networks, we show that reducing spatial correlations or enhancing excitatory transmission can improve memory precision. Altogether, we provide a mechanistic understanding of how cholinergic neuromodulation controls spatial working memory through perturbed attractor dynamics in PFC.

17.
J Colloid Interface Sci ; 660: 608-616, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38266342

ABSTRACT

The skin is the largest organ in the human body and serves vital functions such as sensation, thermal management, and protection. While electronic skin (E-skin) has made significant progress in sensory functions, achieving adaptive thermal management akin to human skin has remained a challenge. Drawing inspiration from squid skin, we have developed a hybrid electronic-photonic skin (hEP-skin) using an elastomer semi-embedded with aligned silver nanowires through interfacial self-assembly. With mechanically adjustable optical properties, the hEP-skin demonstrates adaptive thermal management abilities, warming in the range of +3.5°C for heat preservation and cooling in the range of -4.2°C for passive cooling. Furthermore, it exhibits an ultra-stable high electrical conductivity of âˆ¼4.5×104 S/cm, even under stretching, bending or torsional deformations over 10,000 cycles. As a proof of demonstration, the hEP-skin successfully integrates stretchable light-emitting electronic skin with adaptive thermal management photonic skin.


Subject(s)
Nanowires , Wearable Electronic Devices , Humans , Silver , Skin , Electric Conductivity
18.
Biol Trace Elem Res ; 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38277120

ABSTRACT

Cadmium (Cd) exposure is a persistent pollution problem, necessitating caution in using cadmium-expelling complexing agents. Currently, there is no targeted therapy to treat Cd poisoning. The thyroid gland is a major endocrine organ that directly regulates thyroid hormones involved in various physiological processes and is a target organ for Cd accumulation. Herein, the effects of Cd exposure on swine thyroid glands were investigated. Six-week-old male pigs were randomly divided into the Cd and control groups. The control group was fed a normal diet containing 0 mg Cd/kg, while the Cd group was fed a diet containing 20 mg Cd/kg (CdCl2) for 40 days. The regulation mechanism of phosphatase and tensin homolog (PTEN) microRNA-494-3p (miR-494-3p) was evaluated to determine the toxic effects of Cd exposure on free radicals' cleaner. Notably, heat shock proteins (HSPs) were triggered as defense agents against Cd. Cd exposure increased the enzyme activity of superoxide dismutase1(SOD1) and SOD2, catalase (CAT), and glutathione (GSH), and the endoplasmic reticulum stress in thyroid cells. Histopathological staining, RT-qPCR, and Western Blot assays were further employed to detect possible apoptosis and necroptosis of thyroid cells induced by Cd exposure. The assays revealed increased thyroid inflammatory injury, fibrosis, and apoptosis caused by Cd exposure. This study demonstrates the role of microRNAs in regulating Cd toxicity in pig thyroid tissue and provides evidence of Cd's negative effects. It further provides an assessment of the toxicological impact of Cd as an environmental endocrine disruptor (ED) that threatens public health and safety, which forms a basis for the development of Cd poisoning treatment therapies.

19.
J Neurosci ; 44(2)2024 Jan 10.
Article in English | MEDLINE | ID: mdl-37973375

ABSTRACT

Cortical neurons exhibit multiple timescales related to dynamics of spontaneous fluctuations (intrinsic timescales) and response to task events (seasonal timescales) in addition to selectivity to task-relevant signals. These timescales increase systematically across the cortical hierarchy, for example, from parietal to prefrontal and cingulate cortex, pointing to their role in cortical computations. It is currently unknown whether these timescales are inherent properties of neurons and/or depend on training in a specific task and if the latter, how their modulations contribute to task performance. To address these questions, we analyzed single-cell recordings within five subregions of the prefrontal cortex (PFC) of male macaques before and after training on a working-memory task. We found fine-grained but opposite gradients of intrinsic and seasonal timescales that mainly appeared after training. Intrinsic timescales decreased whereas seasonal timescales increased from posterior to anterior subregions within both dorsal and ventral PFC. Moreover, training was accompanied by increases in proportions of neurons that exhibited intrinsic and seasonal timescales. These effects were comparable to the emergence of response selectivity due to training. Finally, task selectivity accompanied opposite neural dynamics such that neurons with task-relevant selectivity exhibited longer intrinsic and shorter seasonal timescales. Notably, neurons with longer intrinsic and shorter seasonal timescales exhibited superior population-level coding, but these advantages extended to the delay period mainly after training. Together, our results provide evidence for plastic, fine-grained gradients of timescales within PFC that can influence both single-cell and population coding, pointing to the importance of these timescales in understanding cognition.


Subject(s)
Memory, Short-Term , Prefrontal Cortex , Animals , Male , Memory, Short-Term/physiology , Prefrontal Cortex/physiology , Macaca , Neurons/physiology , Primates
20.
Environ Pollut ; 343: 123120, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38072019

ABSTRACT

Human skin wipes from 30 participants, air, dust, and food items were collected from a former electronic waste site in South China to provide a comprehensive understanding of residents' exposure to halogenated flame retardants (HFRs) and polychlorinated biphenyls (PCBs). The total concentration of halogenated organic pollutants (HOPs) in the dust, air, food and skin wipes ranged 240-25000 ng/g, 130-2500 pg/m3, 0.08-590 ng/g wet weight, and 69-28000 ng/m2, respectively. Wild fish, vegetables, and air were dominated by PCBs, whereas dust, livestock, and poultry were dominated by HFRs. The HOP concentrations were several orders of magnitude higher in local foodstuffs than in market foodstuffs. The chemical composition on the forehead was remarkably different from that on the hand. The importance of different exposure routes depends on the residents' food choices, except decabromodiphenyl ethane (DBDPE). For residents who consumed a 100-foot diet (mainly egg) and local wild fish, diet ingestion overwhelmed other exposure routes, and PCBs were mainly contributed by fish and HFRs by egg. For residents who consumed market food, the dermal absorption of most PCB congeners and dust ingestion of highly brominated flame retardants were relatively prominent. Inhalation was found to be a crucial route for pentabromoethylbenzene (PBEB).


Subject(s)
Electronic Waste , Environmental Pollutants , Flame Retardants , Polychlorinated Biphenyls , Animals , Humans , Environmental Exposure/analysis , Persistent Organic Pollutants , Electronic Waste/analysis , Flame Retardants/analysis , Environmental Pollutants/analysis , Dust/analysis , China , Halogenated Diphenyl Ethers/analysis , Environmental Monitoring
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