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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124520, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38796894

RESUMEN

Molecular imprinting is one of the most frequently occurring post-modification in the preparation of covalent organic frameworks (COFs) to enhance selectivity and specificity. In this study, we prepared a 2D layer structure of methoxy-conjugated COFs with the modification of azide (4-azido-L-phenylalanine), named [4-ALP]0.17-COFs, which exhibited a large specific surface area of 827.6 m2/g, good stability of water, polar solvents, chemistry, and thermodynamics. Fluorescent COF nanosheets ([4-ALP]0.17-CONs) obtained by liquid-assisted ultrasonic stripping have excellent blue luminescence properties and ultra-high absolute fluorescence quantum yield of 33.34 %. The modifiable functional groups in the surface of [4-ALP]0.17-CONs interacted with the targets and functional monomers of molecularly imprinted polymers (MIPs) through hydrogen bonding interactions, to form the 3D holes with recognition sites. The quantitative detection of pyrraline (PRL) could be achieved in the concentration range of 0.05-4 µg/L with the LOD was 34.81 ng/L. The spiked recovery of PRL in meat products was 88.01-106.00 %. The [4-ALP]0.17-CONs@MIPs sensing system showed excellent stability, reliability, reusability, and practicability, promising its potential for targeted monitoring of trace molecules in real matrices.

2.
Food Chem ; 452: 139527, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38703741

RESUMEN

Tryptamine is a biogenic amine that affects organoleptic quality through the generation of off-odours in foods. Herein, imine-based covalent organic frameworks (COFs) were synthesized via Schiff base reactions and postmodified with click chemistry to generate azide-functionalized COFs with tunable azide units on the walls. The combination of molecular imprinting with COFs enabled the specific recognition of the targets. The resulting optosensing system (azide-functionalized COFs@MIPs) was used as a sample-to-answer analyser for detecting tryptamine (detection time within 10 min). A linear relationship was observed for the fluorescence response to tryptamine concentrations in the range of 3-120 µg L-1, with a limit of detection of 1.74 µg L-1. The recoveries for spiked samples were satisfactory, with relative standard deviations <9.90%. The optosensing system is a potential tool for the quantitative detection of tryptamine in meat products because of its lower cost, shorter processing time, and simpler processing steps compared to conventional chromatographic techniques.

3.
Tob Induc Dis ; 21: 104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37581174

RESUMEN

INTRODUCTION: The widespread popularity of e-cigarettes is considered an important public health concern. However, only some studies have investigated the prevalence of e-cigarette use in Shanghai, China. Research on the perceived harmfulness of e-cigarettes and public support for e-cigarette regulations in China is limited. This study aimed to estimate e-cigarette awareness, prevalence, and associated factors among adults in Shanghai, China. METHODS: This study used data from a representative survey conducted in Shanghai, China, in 2019. The survey was conducted at 64 surveillance points in Shanghai, China, using a multistage, stratified, cluster-randomized sampling design, recruiting community-based Chinese adults aged ≥15 years. Based on the principles outlined in the Global Adult Tobacco Survey (GATS) China Project, data were collected by conducting face-to-face interviews in households. Of the 3200 selected households, 3060 people completed the individual survey. The overall response rate was 97.4%. RESULTS: In all, 72.3% of the respondents had heard of e-cigarettes. The respondents who had used e-cigarettes at some point in their life, used them in the last 12 months, and used them currently were 5.8%, 2.6%, and 1.3%, respectively. Among adult residents who had heard of e-cigarettes, 38.2% thought they were less harmful than traditional cigarettes. The respondents who perceived e-cigarettes as more harmful than traditional cigarettes were less likely to have ever used e-cigarettes (AOR=0.2; 95% CI: 0.1-0.5, p=0.0015) and more likely to support incorporating e-cigarettes into the regulation of smoking control (AOR=3.9; 95% CI: 1.8-8.6, p=0.0008). CONCLUSIONS: Our findings reveal that the awareness about e-cigarettes was high, and the prevalence of e-cigarette use was similar to the findings from previous studies in China. The harmful perception of e-cigarettes warrants further attention from public health practitioners.

4.
Anal Bioanal Chem ; 415(20): 5011-5021, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37341783

RESUMEN

A thermal-sensitive molecularly imprinted optosensing probe based on fluorescent advanced glycation end products (AGEs) was prepared by one-pot hydrothermal synthesis. Carbon dots (CDs) derived from fluorescent AGEs were used as the luminous centers, while molecularly imprinted polymers (MIPs) were wrapped outside of the CDs to form specific target recognition sites to highly selectively adsorb the intermediate product of AGEs of 3-deoxyglucosone (3-DG). Thermosensitive N-isopropylacrylamide (NIPAM) was combined with acrylamide (AM) as co-functional monomers, and ethylene glycol dimethacrylate (EGDMA) was chosen as a cross-linker for targeting identification and detection of 3-DG. Under optimal conditions, the fluorescence of MIPs could be gradually quenched with the adsorption of 3-DG on the surface of MIPs in the linear range of 1-160 µg/L, and the detection limit was 0.31 µg/L. The spiked recoveries of MIPs ranged from 82.97 to 109.94% in two milk samples, and the relative standard deviations were all less than 1.8%. In addition, the inhibition rate for non-fluorescent AGEs of pyrraline (PRL) was 23% by adsorbing 3-DG in the simulated milk system of casein and D-glucose, indicating that temperature-responsive MIPs not only could detect the dicarbonyl compound 3-DG quickly and sensitively, but also had an excellent inhibitory effect on AGEs.


Asunto(s)
Impresión Molecular , Polímeros , Colorantes Fluorescentes , Carbono , Productos Finales de Glicación Avanzada
5.
Front Immunol ; 14: 1130697, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153558

RESUMEN

Background: Vagus nerve stimulation (VNS) has a protective effect on neurological recovery in ischaemic stroke. However, its underlying mechanism remains to be clarified. Ubiquitin-specific protease 10 (USP10), a member of the ubiquitin-specific protease family, has been shown to inhibit the activation of the NF-κB signalling pathway. Therefore, this study investigated whether USP10 plays a key role in the protective effect of VNS against ischemic stroke and explore its mechanism. Methods: Ischaemic stroke model was constructed by transient middle cerebral artery occlusion (tMCAO) in mice. VNS was performed at 30 min, 24hr, and 48hr after the establishment of tMCAO model. USP10 expression induced by VNS after tMCAO was measured. LV-shUSP10 was used to establish the model with low expression of USP10 by stereotaxic injection technique. The effects of VNS with or without USP10 silencing on neurological deficits, cerebral infarct volume, NF-κB pathway activation, glial cell activation, and release of pro-inflammation cytokines were assessed. Results: VNS enhanced the expression of USP10 following tMCAO. VNS ameliorated neurological deficits and reduced cerebral infarct volume, but this effect was inhibited by silencing of USP10. Activation of the NF-κB pathway and the expression of inflammatory cytokines induced by tMCAO were suppressed by VNS. Moreover, VNS promoted the pro-to-anti-inflammatory response of microglia and inhibited activation of astrocytes, while silencing of USP10 prevented the neuroprotective and anti-neuroinflammatory effects of VNS. Conclusion: USP10 is a potential mediator for VNS to alleviate neurological deficits, neuroinflammation, and glial cell activation in ischaemic stroke by inhibiting NF-κB signalling pathway.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Ubiquitina Tiolesterasa , Estimulación del Nervio Vago , Animales , Ratones , Isquemia Encefálica/metabolismo , Citocinas/metabolismo , Infarto de la Arteria Cerebral Media/terapia , Accidente Cerebrovascular Isquémico/terapia , Enfermedades Neuroinflamatorias , FN-kappa B/metabolismo , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/metabolismo , Estimulación del Nervio Vago/métodos , Ubiquitina Tiolesterasa/genética
6.
Cell Tissue Res ; 392(3): 671-687, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36795153

RESUMEN

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have therapeutic potential in various diseases due to their capacity to transfer bioactive cargoes such as microRNAs (miRNAs or miRs) to recipient cells. The present study isolated EVs from rat MSCs and aimed to delineate their functions and molecular mechanisms in early brain injury following subarachnoid hemorrhage (SAH). We initially determined the expression of miR-18a-5p and ENC1 in hypoxia/reoxygenation (H/R)-induced brain cortical neurons and rat models of SAH induced by the endovascular perforation method. Accordingly, increased ENC1 and decreased miR-18a-5p were detected in H/R-induced brain cortical neurons and SAH rats. After MSC-EVs were co-cultured with cortical neurons, the effects of miR-18a-5p on neuron damage, inflammatory response, endoplasmic reticulum (ER) stress, and oxidative stress markers were evaluated based on ectopic expression and depletion experiments. miR-18a-5p overexpression in brain cortical neurons co-cultured with MSC-EVs was shown to impede neuron apoptosis, ER stress and oxidative stress while augmenting neuron viability. Mechanistically, miR-18a-5p bound to the 3'UTR of ENC1 and reduced its expression, weakening the interaction between ENC1 and p62. Through this mechanism, transfer of miR-18a-5p by MSC-EVs contributed to the eventual inhibition of early brain injury and neurological impairment following SAH. Overall, miR-18a-5p/ENC1/p62 may be a possible mechanism underlying the cerebral protective effects of MSC-EVs against early brain injury following SAH.


Asunto(s)
Lesiones Encefálicas , Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Hemorragia Subaracnoidea , Animales , Ratas , Hemorragia Subaracnoidea/complicaciones , Lesiones Encefálicas/genética , Hipoxia , MicroARNs/genética
7.
Mikrochim Acta ; 190(3): 88, 2023 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-36773114

RESUMEN

A novel and facile method was proposed for preparation of red emissive N-doped carbon dots encapsulated within molecularly imprinted polymers (RNCDs@MIPs) using a one-pot room-temperature reverse microemulsion polymerization. RNCDs used citric acid and urea as carbon and nitrogen sources by one-step solvothermal synthesis with the optimum emission of 620 nm. Unique optical properties of RNCDs coupled with high selective MIPs make the RNCDs@MIPs conjugate capable to adsorb specific targets of pyrraline (PRL), such a binding event was then transduced to quench fluorescence response signal of the RNCDs. RNCDs@MIPs for PRL showed linearity from 0.1 to 40 µg/L, with a detection limit of 65 ng/L. The RNCDs@MIPs exhibited a good reproducibility of 4.67% obtained from four times of rebinding for PRL. The optosensing probe was successfully applied to the detection of PRL in fatty foods with the spiked recovery of 85.93-106.96%.


Asunto(s)
Impresión Molecular , Puntos Cuánticos , Carbono/química , Polímeros Impresos Molecularmente , Impresión Molecular/métodos , Polímeros/química , Reproducibilidad de los Resultados , Puntos Cuánticos/química
8.
Food Chem ; 415: 135715, 2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-36842375

RESUMEN

Herein, we reported the room-temperature fabrication of ionic liquid-modified carbon dots encapsulated in bionic antibodies (IL-modified CDs@BAs) by one-pot green synthesis. In order to enhance the fluorescence intensity of CDs, imidazole ILs and lemon rich in heteroatoms were selected as CDs modifiers and sources. The resulting IL-modified CDs@BAs showed good selectivity and capture toward urea and obviously induced fluorescence quenching by template-binding. The inhibition rate ofIL-modified CDs@BAs on the urea pathway of ethyl carbamate was about 29.07% in the simulated Huangjiu system, indicating a good inhibitory effect. The IL-modified CDs@BAs system was also reproducible after five consecutive uses, thus reducing the economic cost. This research would expand the application fields of BAs-based optical sensing system from the perspectives of energy conservation, environmental protection and resource recovery, focusing on their application in the field of food safety control.


Asunto(s)
Líquidos Iónicos , Puntos Cuánticos , Carbono , Biomasa , Biónica , Microesferas , Anticuerpos , Colorantes Fluorescentes
9.
Environ Sci Pollut Res Int ; 30(11): 29442-29457, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36417062

RESUMEN

Nitrogen pollution in groundwater is an environmental issue of global concern. Identifying nitrogen pollution sources and determining migration and transformation processes are the major ways to prevent and control nitrogen pollution in the groundwater on a regional scale. In this study, groundwater in the lower Wei River was investigated by combining multi-isotope tracing techniques with the SIAR hybrid model (source resolution) to trace the nitrate sources and their contribution rate to nitrogen pollution in groundwater of different geomorphological units, considering types of geomorphology as the units. The multi-isotope tracing technique allows dynamic analysis of nitrate sources, and the combination of this technology can improve the accuracy of nitrogen source traceability. The results indicated that the pH of the water bodies in the study area ranged from 6.83 to 8.01, which is neutral and weakly alkaline. The nitrogen pollution was mainly due to nitrates. The significant factors affecting nitrogen migration in groundwater are the geomorphological type, the chemical characteristics of the groundwater, and the age of the groundwater. Nitrogen migration and transformation processes in the study area were dominated by nitrification, and sources of nitrate pollution were mainly animal manure and domestic sewage (32.6%), followed by atmospheric deposition (26.8%), soil nitrogen (20.9%), and chemical fertilizer (19.7%). The main sources of nitrate in groundwater from river flats, alluvial plains, and loess tableland were animal manure and domestic sewage (43.7%), animal manure and domestic sewage (59.1%), and atmospheric deposition (55.5%), respectively. The result is mainly related to the different structural characteristics of various geomorphic units and the intensity of human activities. This study can provide a theoretical basis for the relevant agencies to develop plans to combat groundwater pollution.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Animales , Humanos , Nitrógeno/análisis , Nitratos/análisis , Isótopos de Nitrógeno/análisis , Ríos/química , Estiércol/análisis , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Agua Subterránea/química , China
10.
Neurochem Res ; 48(2): 502-518, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36322371

RESUMEN

Accumulating evidence of the critical role of Ferrostatin-1 (Fer-1, ferroptosis inhibitor) in cerebral ischemia has intrigued us to explore the molecular mechanistic actions of Fer-1 delivery by bone marrow mesenchymal stem cells-derived extracellular vesicles (MSCs-EVs) in cerebral ischemia-reperfusion (I/R) injury. In vivo middle cerebral artery occlusion (MCAO) in mice and in vitro oxygen-glucose deprivation/reperfusion (OGD/R) in hippocampal neurons were developed to simulate cerebral I/R injury. After Fer-1 was confirmed to be successfully delivered by MSCs-EVs to neurons, we found that MSCs-EVs loaded with Fer-1 (MSCs-EVs/Fer-1) reduced neuron apoptosis and enhanced viability, along with curtailed inflammation and ferroptosis. The regulation of Fer-1 on GPX4/COX2 axis was predicted by bioinformatics study and validated by functional experiments. The in vivo experiments further confirmed that MSCs-EVs/Fer-1 ameliorated cerebral I/R injury in mice. Furthermore, poor expression of GPX4 and high expression of COX-2 were witnessed in cerebral I/R injury models. MSCs-EVs/Fer-1 exerted its protective effects against cerebral I/R injury by upregulating GPX4 expression and inhibiting COX-2 expression. Taken together, our study indicates that MSCs-EVs/Fer-1 may be an attractive therapeutic target for the treatment of cerebral I/R injury due to its anti-ferroptotic properties.


Asunto(s)
Isquemia Encefálica , Vesículas Extracelulares , Células Madre Mesenquimatosas , Daño por Reperfusión , Ratones , Animales , Ciclooxigenasa 2/metabolismo , Vesículas Extracelulares/metabolismo , Isquemia Encefálica/metabolismo , Daño por Reperfusión/metabolismo , Células Madre Mesenquimatosas/metabolismo
11.
Environ Sci Pollut Res Int ; 30(3): 5799-5814, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35980525

RESUMEN

To study the inorganic nitrogen in the process of interaction of river and groundwater and the changes in the microbial community, a vertical simulation device was used to simulate groundwater recharge to river water (upwelling) and river water recharge to groundwater (downwelling). The inorganic nitrogen concentrations in the soil and water solution as well as the characteristics of the microbial community were assessed to determine the inorganic nitrogen transformation and microbial community response in the heterogeneous interaction zone under hydrodynamic action, and the interaction mechanism between nitrogen transformation and the microbial community in the interaction zone was revealed. The removal rates of NO3--N in the simulated solution reached 99.1% and 99.3% under the two fluid-groundwater conversion modes, and the prolonged hydraulic retention time (HRT) of the oxidization-reduction layer in the fine clay area and the high organic matter content made the inorganic nitrogen transformation process dominated by microorganisms more complete. The denitrification during upwelling, dominated by denitrifying bacteria in Sphingomonas, Pseudomonas, Bacillus, and Arthrobacter, was stronger than that during downwelling. Dissimilatory nitrate reduction to ammonium (DNRA), controlled by some aerobic bacteria in Pseudomonas, Bacillus, and Desulfovibrio, was more intense in downflow mode than upflow mode.


Asunto(s)
Compuestos de Amonio , Bacillus , Agua Subterránea , Microbiota , Nitrógeno , Hidrodinámica , Desnitrificación , Nitratos , Agua
12.
Sensors (Basel) ; 22(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502074

RESUMEN

In this paper, a fast-transient-response NMOS low-dropout regulator (LDO) with a wide load-capacitance range was presented to provide a V/2 read bias for cross-point memory. To utilize the large dropout voltage in the V/2 bias scheme, a fast loop consisting of NMOS and flipped voltage amplifier (FVA) topology was adopted with a fast transient response. This design is suitable to provide a V/2 read bias with 3.3 V input voltage and 1.65 V output voltage for different cross-point memories. The FVA-based LDO designed in the 110 nm CMOS process remained stable under a wide range of load capacitances from 0 to 10 nF and equivalent series resistance (ESR) conditions. At the capacitor-less condition, it exhibited a unity-gain bandwidth (UGB) of approximately 400 MHz at full load. For load current changes from 0 to 10 mA within an edge time of 10 ps, the simulated undershoot and settling time were only 144 mV and 50 ns, respectively. The regulator consumed 70 µA quiescent current and achieved a remarkable figure-of-merit (FOM) of 1.01 mV. At the ESR condition of a 1 µF off-chip capacitor, the simulated quiescent current, on-chip capacitor consumption, and current efficiency at full load were 8.5 µA, 2 pF, and 99.992%, respectively. The undershoot voltage was 20 mV with 800 ns settling time for a load step from 0 to 100 mA within the 10 ps edge time.


Asunto(s)
Amplificadores Electrónicos , Capacidad Eléctrica
13.
Front Neurosci ; 16: 1026152, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36408414

RESUMEN

Burn injury is a devastating disease with high incidence of disability and mortality. The cognitive dysfunctions, such as memory defect, are the main neurological sequelae influencing the life quality of burn-injured patients. The post-burn cognitive dysfunctions are related to the primary peripheral factors and the secondary cerebral inflammation, resulting in the destruction of blood-brain barrier (BBB), as is shown on Computed Tomography (CT) and magnetic resonance imaging examinations. As part of the neurovascular unit, BBB is vital to the nutrition and homeostasis of the central nervous system (CNS) and undergoes myriad alterations after burn injury, causing post-burn cognitive defects. The diagnosis and treatment of cognitive dysfunctions as burn injury sequelae are of great importance. In this review, we address the major manifestations and interventions of post-burn cognitive defects, as well as the mechanisms involved in memory defect, including neuroinflammation, destruction of BBB, and hormone imbalance.

14.
Oxid Med Cell Longev ; 2022: 3858314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36338345

RESUMEN

Ischemic stroke exhibits high morbidity, disability, and mortality, and treatments for ischemic stroke are limited despite intensive research. The potent neuroprotective benefits of Epimedium against ischemic stroke have gained lots of interest. Nevertheless, systematic research on the direct role and mechanisms of Epimedium in ischemic stroke is still lacking. Network pharmacology analysis coupled with experimental verification was utilized to systematically evaluate the potential pharmacological mechanism of Epimedium against ischemic stroke. The TCMSP database was used to mine the bioactive ingredients and Epimedium's targets. The DrugBank, OMIM, and GeneCards databases were employed to identify potential targets of ischemic stroke. GO and KEGG pathway analyses were also carried out. The interaction between active components and hub targets was confirmed via molecular docking. An experimental ischemic stroke model was used to evaluate the possible therapeutic mechanism of Epimedium. As a result, 23 bioactive compounds of Epimedium were selected, and 30 hub targets of Epimedium in its function against ischemic stroke were identified, and molecular docking results demonstrated good binding. The IL-17 signaling pathway was revealed as a potentially significant pathway, with the NF-κB and MAPK/ERK signaling pathways being involved. Furthermore, in vivo experiments demonstrated that Epimedium treatment could improve neurological function and reduce infarct volume. Additionally, Epimedium reduced the activation of microglia and astrocytes in both the ischemic penumbra of the hippocampus and cerebral cortex following ischemic stroke. Western blot and RT-qPCR analyses demonstrated that Epimedium not only depressed the expression of IL-1ß, TNF-α, IL-6, and IL-4 but also inhibited the NF-κB and MAPK/ERK signaling pathways. This study applied network pharmacology and in vivo experiment to explore possible mechanism of Epimedium's role against ischemic stroke, which provides insight into the treatment of ischemic stroke.


Asunto(s)
Medicamentos Herbarios Chinos , Epimedium , Accidente Cerebrovascular Isquémico , Humanos , Epimedium/química , Epimedium/metabolismo , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , FN-kappa B/metabolismo , Simulación del Acoplamiento Molecular , Farmacología en Red , Medicamentos Herbarios Chinos/farmacología
15.
Front Aging Neurosci ; 14: 940166, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36051307

RESUMEN

Backgroud: Vascular dementia is the second most common cause of dementia after Alzheimer's disease, accounting for an estimated 15% of cases. Recently, Epimedium has attracted great attention for its potential neuroprotective benefit. However, the direct role and mechanism of Epimedium on vascular dementia still lack systematic research. To systematically explore the possible pharmacological mechanism of Epimedium for the treatment of vascular dementia, network pharmacology, molecular docking, combined with experiment validation were conducted. Methods: The bioactive compounds and targets of Epimedium were obtained from the TCMSP database. The potential targets of vascular dementia were identified from the DrugBank, OMIM, Genecards, Therapeutic Target Database, and DisGeNET databases. GO and KEGG pathway analyses were performed. Molecular docking was applied to validate the interaction between active components and hub targets. The bilateral common carotid artery occlusion (BCCAO) method was used for construction of a vascular dementia model in mice. The effects of Epimedium on learning and memory ability were examined by behavioral tests. The mechanisms of the cerebral protective effects of Epimedium were evaluated by WB, RT-PCR, and immunofluorescence. Results: A total of 23 Epimedium active ingredients, and 71 intersecting targets of Epimedium against vascular dementia were obtained. The top five hub targets AKT1, TNF, IL1ß, IL6, and MMP9 were identified, and molecular docking showed good binding. GO enrichment showed a total of 602 enrichment results, with 458 (80.56%) key targets mainly focused on biological processes (BP). The response to hypoxia, positive regulation of nitric oxide biosynthetic process, aging, inflammatory response, cellular response to lipopolysaccharide, negative regulation of apoptotic process were well ranked. KEGG pathway enrichment analysis identified the TNF signaling pathway as an important pathway, with the MAPK/extracellular signal-regulated kinase (ERK) and NF-κB signaling pathways as the key pathways involved. Consistently, in vivo experiments showed that Epimedium treatment improved learning and memory functions in mice with vascular dementia. In addition, Epimedium attenuated the activation of microglia and astrocytes in the hippocampal region after BCCAO. RT-qPCR and Western blot analysis showed that Epimedium not only affected the expression of AKT, TNF, IL1ß, IL6, and MMP9, but also suppressed the TNF signaling pathway. Conclusion: Epimedium may exert a protective effect against vascular dementia through the alleviation of oxidative stress, neuroinflammation, BBB dysfunction, apoptosis through TNF signaling pathway. This study explored the mechanism of Epimedium on vascular dementia systematically through network pharmacological and in vivo experiment approach, which provides insight into the treatment of vascular dementia.

16.
Front Neurorobot ; 16: 948386, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966373

RESUMEN

As information technology is moving toward the era of big data, the traditional Von-Neumann architecture shows limitations in performance. The field of computing has already struggled with the latency and bandwidth required to access memory ("the memory wall") and energy dissipation ("the power wall"). These challenging issues, such as "the memory bottleneck," call for significant research investments to develop a new architecture for the next generation of computing systems. Brain-inspired computing is a new computing architecture providing a method of high energy efficiency and high real-time performance for artificial intelligence computing. Brain-inspired neural network system is based on neuron and synapse. The memristive device has been proposed as an artificial synapse for creating neuromorphic computer applications. In this study, post-silicon nano-electronic device and its application in brain-inspired chips are surveyed. First, we introduce the development of neural networks and review the current typical brain-inspired chips, including brain-inspired chips dominated by analog circuit and brain-inspired chips of the full-digital circuit, leading to the design of brain-inspired chips based on post-silicon nano-electronic device. Then, through the analysis of N kinds of post-silicon nano-electronic devices, the research progress of constructing brain-inspired chips using post-silicon nano-electronic device is expounded. Lastly, the future of building brain-inspired chips based on post-silicon nano-electronic device has been prospected.

17.
J Microsc ; 287(3): 148-155, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35789488

RESUMEN

The phase image of tapping-mode atomic force microscopy (TM-AFM) contains energy dissipation, which is related to the sample information on the physical properties such as the sample Young's modulus, adhesion, surface morphology and subsurface morphology. When TM-AFM is used for sample measurement, the frequency near the first resonance peak of probe is usually selected to drive the probe vibration. When the probe vibration is driven by the frequency, the probe has a high amplitude sensitivity, but the phase sensitivity is relatively low. In this paper, the frequency at the probe phase resonance peak was selected for driving the probe vibration to measure the sample, which improved the image resolution. Phase imaging was performed on three uniform photoresist samples with different thicknesses and the same structure. When the scanning parameters were fixed and the probe setpoint value was changed alone, it was found that with the decrease of setpoint value the horizontal resolution of the phase subsurface image was decreased, and the depth sensitivity was increased first and then decreased. The result shows that TM-AFM working at the phase resonance peak can better realise the subsurface imaging of samples at different depths. Phase subsurface imaging at the resonance can be used to quantitatively obtain subsurface phase images of different depths.


Asunto(s)
Vibración , Módulo de Elasticidad , Microscopía de Fuerza Atómica/métodos
18.
Anal Methods ; 14(18): 1820-1826, 2022 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-35481818

RESUMEN

Various cell culture substrates have been developed for cell patterning to control cell distributions and orientations in tissue engineering, drug screening and regenerative medicine. In this study, a preparation method of modified fiber membranes was applied in the field of cell patterning, and the obtained fiber membranes guided the cell distributions and orientations flexibly. The aligned electrospinning fiber membranes were dip-coated with polydimethylsiloxane (PDMS) to improve the stability of wettability, and then it was treated with oxygen plasma with a photomask to obtain a hydrophilic-hydrophobic surface micropattern. The morphologies, wettabilities and chemical structures of the membranes were analyzed by using a scanning electron microscope (SEM), drop shape analysis instrument, energy dispersive spectrometer (EDS) and Fourier transform infrared (FTIR) spectrometer. The L929 cells were cultured on the obtained membranes to observe the controlled cell distributions and orientations by using a SEM and fluorescence microscope. The results indicate that the treated membranes have the ability to control both cell distributions and orientations simultaneously. This method offers a novel approach to develop cell culture substrates for cell patterning in tissue engineering.


Asunto(s)
Dimetilpolisiloxanos , Ingeniería de Tejidos , Técnicas de Cultivo de Célula , Dimetilpolisiloxanos/química , Humectabilidad
19.
Cell Death Discov ; 8(1): 54, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35136042

RESUMEN

Cumulative evidence suggests that pyroptosis, a new sort of programmed cell death, is closely related to cerebral ischemia/reperfusion (I/R) injury. Our previous studies have testified that vagus nerve stimulation (VNS) was involved in many different neuroprotective and neuroplasticity pathways via α7 nicotinic acetylcholine receptor (α7nAchR), a vital node of the cholinergic anti-inflammatory pathway during cerebral I/R injury. We aimed to determine the neuroprotective effects of VNS through α7nAchR-mediated inhibition of pyroptosis. Focal cerebral ischemic stroke rat models were obtained by middle cerebral artery occlusion for 120 min. Expression of the NLRP3 inflammasome was evaluated using western blotting and immunofluorescence (IF) staining. The neurological deficit score, infarct volume, TUNEL staining findings, transmission electron microscopy findings, and expression of inflammatory cytokines were assessed 3 days after I/R injury. Our findings suggested that the protein expression levels of NLRP3, GSDMD-N, cleaved caspase-1, and ASC gradually increased until they peaked on day 3 after I/R injury. VNS inhibited the expression of pyroptosis-related molecules and decreased the number of pyroptotic cells and membrane pores. Administration of α7nAchR-antagonist and agonist helped in further assessment of the role of α7nAchR in pyroptosis. α7nAchR-agonist mimicked VNS's neuroprotective effects on the improvement of neurological deficits, the reduction of infarct volumes, and the inhibition of neuronal pyroptosis after cerebral I/R injury. Conversely, the neuroprotection provided by VNS could be reversed by the administration of α7nAchR-antagonist. In conclusion, VNS-induced neuroprotection via inhibition of neuronal pyroptosis was α7nAchR-dependent, highlighting the pivotal role of α7nAChR in suppressing cellular pyroptosis and neuroinflammation. These findings may allow a better understanding of treatment principles for cerebral I/R injury.

20.
Neural Regen Res ; 17(8): 1809-1813, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35017442

RESUMEN

Transcutaneous auricular vagus nerve stimulation (ta-VNS) is a novel noninvasive treat-ment for stroke that directly stimulates the peripheral auricular branch of the vagus nerve. There have been recent reports that ta-VNS combined with conventional rehabilitation training promotes the recovery of neurological function of patients with acute stroke. However, these were small-sample-sized studies on the recovery of neurological function in patients after percutaneous vagus nerve stimulation in the subacute and chronic phases after stroke. This double-blinded randomized controlled trial involved 60 acute ischemic or hemorrhagic stroke patients aged 18-80 years who received treatment in the Second Affiliated Hospital of Chongqing Medical University. The subjects were randomly assigned to receive ta-VNS or sham ta-VNS combined with conventional rehabilitation training. The follow-up results over 1 year revealed that ta-VNS combined with conventional rehabilitation training greatly improved the recovery of motor and sensory functions and emotional responses compared with sham ta-VNS combined with conventional rehabilitation training. There were no obvious side effects. These findings suggest that ta-VNS combined with conventional rehabilitation training for the treatment of acute ischemic or hemorrhagic stroke patients is safe and effective.

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