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1.
Langmuir ; 39(7): 2618-2630, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36775933

RESUMO

The application of intrinsic and transition metals (TM)-doped VSe2 monolayers for the detection of faulty gases in SF6 electrical insulated equipment is investigated based on first-principles calculations. The electron density difference, density of state, and adsorption energy are analyzed to further clarify the reaction mechanism. The results show that the intrinsic VSe2 monolayer has weak adsorption performance for SO2 and SOF2 molecules, but the adsorption properties of the system are significantly improved after doping TM atoms. Among them, the TM-doped VSe2 monolayer has better sensing performance for SO2 than for SOF2 molecules. Furthermore, the modulating effect of biaxial strain on the gas-sensitive properties of TM-doped VSe2 system is also analyzed. Finally, the recovery time of the gas molecules on the solid adsorbent is evaluated. The results confirm that the TM-doped VSe2 monolayer can be used as a novel sensing material or scavenger to ensure the normal operation of SF6 electrical insulated equipment. This will provide a prospective insight for experimenters to implement VSe2-based sensing materials or scavengers.

2.
Langmuir ; 39(31): 10769-10778, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37491738

RESUMO

Building two-dimensional (2D) vertical van der Waals heterostructures (vdWHs) is one of the effective methods to regulate the properties of single 2D materials. In this paper, we stack the hexagonal boron nitride (h-BN) monolayer (ML) on the SnSe2 ML to construct the stable h-BN/SnSe2 vdWH, of which the crystal and electronic structures, together with the optical properties, are also analyzed by the first-principles calculations. The results show that the h-BN/SnSe2 vdWH belongs to a type-I heterostructure with an indirect bandgap of 1.33 eV, in which the valence band maximum and conduction band minimum are both determined by the component SnSe2 ML. Interestingly, the h-BN/SnSe2 vdWH under the tensile strain or electric field undergoes the transitions both from type-I to type-II heterostructure and from the indirect to direct bandgap semiconductor. In addition, the carrier mobility of the h-BN/SnSe2 heterostructure has a significant enhancement relative to that of the SnSe2 ML, up to 104 cm2 V-1 s-1. Meanwhile, the h-BN/SnSe2 heterostructure presents the superb optical absorption and unique type-II hyperbolic property. Our findings will broaden the potential applications of SnSe2 ML and provide theoretical guidance for the related experimental studies.

3.
Phys Chem Chem Phys ; 24(33): 19895-19910, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35960000

RESUMO

A SnS monolayer is a new two-dimensional material with a black phosphorous structure, with high carrier mobility and a large surface-to-volume ratio, and is an ideal candidate material for gas sensors. The adsorption and sensing behaviors between the SnS monolayer and gas molecules are enhanced under the action of TM atoms with high catalytic performance. The adsorption behavior of CO and H2S on intrinsic and transition metal atom modified SnS monolayers is investigated based on the first principles calculations. The adsorption structure, adsorption energy, electron transfer, density of states, electron local density, work function, and desorption properties are discussed to evaluate the potential applications of SnS monolayers as scavengers and gas sensors for CO and H2S molecules. The results show that Ni, Pd, Pt and Cu atoms tend to be adsorbed on TH sites, while Ag and Au atoms are more easily captured by TS sites. Further studies have shown that all TM atoms can significantly enhance the sensing behavior between the SnS monolayer and the gas molecules. The adsorption performance of the CO molecule on the TM-mediated SnS (TM-SnS) monolayer is obviously better than that of the H2S molecule. Furthermore, the effects of electric field and biaxial strain on the sensing properties of gas molecules on Ni-SnS monolayers are also investigated. Finally, the desorption time of gas molecules from the TM-SnS monolayer is estimated. This will provide experimenters with theoretical guidance for the application of SnS-based sensing materials, and our work is of great significance for predicting new monochalcogenide sensing materials.

4.
Heliyon ; 10(12): e33144, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39005910

RESUMO

Immunotherapy has been an advanced and effective approach to treating various types of solid tumors in recent years, and the most successful strategy is immune checkpoint inhibitors (ICIs), which have shown beneficial effects in patients with colorectal cancer (CRC). Drug resistance to ICIs is usually associated with CD8+ T-cells targeting tumor antigens; thus, CD8+ T-cells play an important role in immunotherapy. Unfortunately, Under continuous antigen stimulation, tumor microenvironment(TME), hypoxia and other problems it leads to insufficient infiltration of CD8+ T-cells, low efficacy and mechanism exhaustion, which have become obstacles to immunotherapy. Thus, this article describes the relationship between CRC and the immune system, focuses on the process of CD8+ T-cells production, activation, transport, killing, and exhaustion, and expounds on related mechanisms leading to CD8+ T-cells exhaustion. Finally, this article summarizes the latest strategies and methods in recent years, focusing on improving the infiltration, efficacy, and exhaustion of CD8+ T-cells, which may help to overcome the barriers to immunotherapy.

5.
Adv Sci (Weinh) ; : e2404444, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965797

RESUMO

The trap states at both the upper and bottom interfaces of perovskite layers significantly impact non-radiative carrier recombination. The widely used solvent-based passivation methods result in the disordered distribution of surface components, posing challenges for the commercial application of large-area perovskite solar cells (PSCs). To address this issue, a novel NH3 gas-assisted all-inorganic dual-interfaces passivation strategy is proposed. Through the gas treatment of the perovskite surface, NH3 molecules significantly enhanced the iodine vacancy formation energy (1.54 eV) and bonded with uncoordinated Pb2+ to achieve non-destructive passivation. Meanwhile, the reduction of the film defect states is accompanied by a decrease in the work function, which promotes carrier transport between the interface. Further, a stable passivation layer is constructed to manage the bottom interfacial defects using inorganic potassium tripolyphosphate (PT), whose ─P═O group effectively mitigated the charged defects and lowered the carrier transport barriers and nucleation barriers of PVK, while the gradient distribution of K+ improved the crystalline quality of PVK film. Based on the dual-interface synergistic effect, the optimal MA-contained PSCs with an effective area of 0.1 cm2 achieved an efficiency of 24.51% and can maintain 90% of the initial value after aging (10-20% RH and 20 °C) for 2000 h.

6.
Sci Adv ; 10(30): eado3141, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39047111

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH) is regulated by complex interplay between the macrophages and surrounding cells in the liver. Here, we show that Atf3 regulates glucose-fatty acid cycle in macrophages attenuates hepatocyte steatosis, and fibrogenesis in hepatic stellate cells (HSCs). Overexpression of Atf3 in macrophages protects against the development of MASH in Western diet-fed mice, whereas Atf3 ablation has the opposite effect. Mechanistically, Atf3 improves the reduction of fatty acid oxidation induced by glucose via forkhead box O1 (FoxO1) and Cd36. Atf3 inhibits FoxO1 activity via blocking Hdac1-mediated FoxO1 deacetylation at K242, K245, and K262 and increases Zdhhc4/5-mediated CD36 palmitoylation at C3, C7, C464, and C466; furthermore, macrophage Atf3 decreases hepatocytes lipogenesis and HSCs activation via retinol binding protein 4 (Rbp4). Anti-Rbp4 can prevent MASH progression that is induced by Atf3 deficiency in macrophages. This study identifies Atf3 as a regulator of glucose-fatty acid cycle. Targeting macrophage Atf3 or Rbp4 may be a plausible therapeutic strategy for MASH.


Assuntos
Fator 3 Ativador da Transcrição , Macrófagos , Animais , Fator 3 Ativador da Transcrição/metabolismo , Fator 3 Ativador da Transcrição/genética , Camundongos , Macrófagos/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/etiologia , Células Estreladas do Fígado/metabolismo , Ácidos Graxos/metabolismo , Glucose/metabolismo , Fígado/metabolismo , Fígado/patologia , Hepatócitos/metabolismo , Antígenos CD36/metabolismo , Antígenos CD36/genética , Lipogênese , Humanos , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Reprogramação Celular , Camundongos Endogâmicos C57BL , Reprogramação Metabólica
7.
J Mol Cell Biol ; 14(10)2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36472556

RESUMO

Lipids and glucose exert many essential physiological functions, such as providing raw materials or energy for cellular biosynthesis, regulating cell signal transduction, and maintaining a constant body temperature. Dysregulation of lipid and glucose metabolism can lead to glucolipid metabolic disorders linked to various metabolic diseases, such as obesity, diabetes, and cardiovascular disease. Therefore, intervention in glucolipid metabolism is a key therapeutic strategy for the treatment of metabolic diseases. Activating transcription factor 3 (ATF3) is a transcription factor that acts as a hub of the cellular adaptive-response network and plays a pivotal role in the regulation of inflammation, apoptosis, DNA repair, and oncogenesis. Emerging evidence has illustrated the vital roles of ATF3 in glucolipid metabolism. ATF3 inhibits intestinal lipid absorption, enhances hepatic triglyceride hydrolysis and fatty acid oxidation, promotes macrophage reverse cholesterol transport, and attenuates the progression of western diet-induced nonalcoholic fatty liver disease and atherosclerosis. In addition to its role in lipid metabolism, ATF3 has also been identified as an important regulator of glucose metabolism. Here, we summarize the recent advances in the understanding of ATF3, mainly focusing on its role in glucose and lipid metabolism and potential therapeutic implications.


Assuntos
Fator 3 Ativador da Transcrição , Doenças Metabólicas , Humanos , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Fígado/metabolismo , Doenças Metabólicas/metabolismo , Glucose/metabolismo , Metabolismo dos Lipídeos , Lipídeos
8.
Digit Health ; 9: 20552076231181473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342095

RESUMO

Background: As a principal cause of mortality and disability worldwide, stroke imposes considerable burdens on society and effects on the lives of patients, families, and communities. Owing to their growing global popularity, health-related applications (apps) offer a promising approach to stroke management but show a knowledge gap regarding mobile apps for stroke survivors. Methods: This review was conducted across the Android and iOS app stores in September-December 2022 to identify and describe all apps targeting stroke survivors. Apps were included if they were designed for stroke management and contained at least one of the following components: medication taking, risk management, blood pressure management, and stroke rehabilitation. Apps were excluded if they were unrelated to health, not in Chinese or English, or the targeted users were healthcare professionals. The included apps were downloaded, and their functionalities were investigated. Results: The initial search yielded 402 apps, with 115 eligible after title and description screening. Some apps were later excluded due to duplicates, registration problems, or installation failures. In total, 83 apps were included for full review and evaluated by three independent reviewers. Educational information was the most common function (36.1%), followed by rehabilitation guidance (34.9%), communication with healthcare providers (HCPs), and others (28.9%). The majority of these apps (50.6%) had only one functionality. A minority had contributions from an HCP or patients. Conclusion: With the widespread accessibility and availability of smartphone apps across the mHealth landscape, an increasing number of apps targeting stroke survivors are being released. One of the most important findings is that the majority of the apps were not specifically geared toward older adults. Many of the currently available apps lack healthcare professionals' and patients' involvement in their development, and most offer limited functionality, thus requiring further attention to the development of customized apps.

9.
Dev Cell ; 58(21): 2326-2337.e5, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37863040

RESUMO

High-density lipoprotein (HDL) metabolism is regulated by complex interplay between the scavenger receptor group B type 1 (SR-BI) and multiple signaling molecules in the liver. Here, we show that lipocalin-2 (Lcn2) is a key regulator of hepatic SR-BI, HDL metabolism, and atherosclerosis. Overexpression of human Lcn2 in hepatocytes attenuates the development of atherosclerosis via SR-BI in western-diet-fed Ldlr-/- mice, whereas hepatocyte-specific ablation of Lcn2 has the opposite effect. Mechanistically, hepatocyte Lcn2 improves HDL metabolism and alleviates atherogenesis by blocking Nedd4-1-mediated SR-BI ubiquitination at K500 and K508. The Lcn2-improved HDL metabolism is abolished in mice with hepatocyte-specific Nedd4-1 or SR-BI deletion and in SR-BI (K500A/K508A) mutation mice. This study identifies a regulatory axis from Lcn2 to HDL via blocking Nedd4-1-mediated SR-BI ubiquitination and demonstrates that hepatocyte Lcn2 may be a promising target to improve HDL metabolism to treat atherosclerotic cardiovascular diseases.


Assuntos
Aterosclerose , Lipoproteínas HDL , Camundongos , Humanos , Animais , Lipoproteínas HDL/metabolismo , Lipocalina-2/genética , Lipocalina-2/metabolismo , Hepatócitos/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Fígado/metabolismo , Antígenos CD36/metabolismo
10.
Int J Biol Macromol ; 115: 1189-1193, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29654859

RESUMO

Starch-based hydrogel containing azo group (SHA) was prepared through radical cross-linking reaction among starch- and PVA-based macromonomers, acrylic acid (AA) and 4-acryloyoxyazobenzene (AHAB). AHAB was prepared through an acylation reaction between acryloyl chloride and 4-hydroxyazobenzene (p-HAB), which was obtained by the diazo coupling reaction between aniline and phenol. The structure of SHA was confirmed with Fourier transform infrared spectrometer, thermogravimetric analysis and UV-Visible spectroscopy. SHA displayed pH-sensitive swelling in buffer saline. SHA film also exhibited a reversible trans-cis-trans photoisomerization behavior when they were subjected to alternative UV and visible light irradiation or dark storage. The dual-responsive characteristic was easily to be tailored via varying the initial amount of AHAB or AA.


Assuntos
Compostos Azo/química , Ácidos Carboxílicos/química , Hidrogéis/química , Amido/química , Técnicas de Química Sintética
11.
J Colloid Interface Sci ; 524: 465-474, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29677615

RESUMO

We successfully design and construct urchin-like non-precious-metal bifunctional oxygen electrocatalysts via a two-step pyrolysis process, where nitrogen, sulfur co-doped carbon nanotube frameworks are grafted onto mesoporous cobalt sulfide/nitrogen, sulfur co-doped carbon spheres. The urchin-like structure grants large electrochemically active area, good electron and mass transfer capability, as well as excellent structural stability. Nitrogen, sulfur co-doped carbon can synergistically enhance the catalytic activity of cobalt sulfide sites, and also contribute to the exposure of heteroatom-induced active sites, such as, pyridinic N, graphitic N, and C-S-C. Hence, benefiting from the unique architecture and efficient catalytic sites, the resulting catalysts demonstrate excellent bifunctional catalytic activities with a positive half-wave potential of 0.860 V vs. RHE for oxygen reduction reaction and low overpotential of ∼390 mV at the current density of 10 mA cm-2 for oxygen evolution reaction in alkaline medium, which can rank them among one of the most promising cobalt-based bifunctional oxygen electrocatalysts reported previously.

12.
ACS Appl Mater Interfaces ; 10(39): 33124-33134, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30199229

RESUMO

It is a critical challenge to construct efficient precious-metal-free bifunctional oxygen electrocatalysts for fuel cell and metal-air batteries via structural and component engineering. Herein, a one-dimensional mesoporous double-layered tubular structure, where Co9S8 nanocrystals are incorporated into nitrogen, sulfur codoped carbon, is successfully synthesized via the coordinated-assisted polymerization and sacrificial template methods. The double-layered tubular structure provides for a large electrochemically active surface area and promotes fast mass transfer. Cobalt oxides/oxyhydroxides, which are evolved from the sulfides during the catalytic processes, as the main active sites efficiently catalyze the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), in cooperation with the Co-N-C and heteroatom-induced active sites. Hence, it demonstrates excellent bifunctional electrocatalytic activity with the overvoltage between the OER potential at 10 mA cm-2 ( E10) and ORR half-wave potential ( E1/2) of 0.707 V, which is superior to most of precious-metal-free bifunctional oxygen electrocatalysts reported recently, as well as the state-of-art Pt/C and RuO2 catalysts.

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