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1.
J Colloid Interface Sci ; 674: 19-28, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38909591

RESUMO

Exploring robust electrode materials which could permit fast and reversible insertion/extraction of large K+ is a crucial challenge for potassium-ion batteries (PIBs). Smart interfacial design could facilitate electron/ion transport as well as assure the integrity of electrode. Herein, Cetyltrimethylammonium bromide (CTAB) was found to play bifunctional roles in construction of Nb2CTx@MoSe2 heterostructure. Firstly, functionalization of CTAB on the surface of Nb2CTx could influence the subsequent growth of MoSe2 by electrostatic effect, stereochemical effect and the synergetic Lewis acid-base interaction, leading to the formation of Nb2CTx@MoSe2 with tiled heterostructure. Secondly, the interlayer spacing of Nb2CTx was expanded from 0.77 to 1.21 nm owing to the pillar effect of CTAB. As excepted, the capacity retention was 80 % from 100 mA g-1 (406 mA h g-1) to 1000 mA g-1 concerning rate capability and the specific capacity maintained at 240 mA h g-1 (at 2000 mA g-1) over 300 cycles. The calculated DK values from Galvanostatic intermittent titration technique (GITT) measurement of the titled C-T-Nb2CTx@MoSe2@C electrode is two orders of magnitude larger than the traditional T-Nb2CTx@MoSe2@C electrode, further confirming intimate interface between MoSe2 and Nb2CTx could provide convenient potassium-ion transport channels and fast diffusion kinetics. Finally, ex-situ characterizations at different charging and discharging voltage stages, including ex-situ XRD/Raman/HRTEM/XPS have been carried out to reveal the potassium storage mechanism. This work provides a facile strategy for the regulation of interface engineering by the assist of CTAB which could extend to other MXenes-TMDs (Transition metal dichalcogenides) hybrid electrodes.

2.
Chem Sci ; 15(9): 3262-3272, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38425519

RESUMO

The precisely engineered structures of materials greatly influence the manifestation of their properties. For example, in the process of alkali metal ion storage, a carefully designed structure capable of accommodating inserted and extracted ions will improve the stability of material cycling. The present study explores the uniform distribution of self-grown carbon nanotubes to provide structural support for the conductive and elastic MXene layers of Ti3C2Tx-Co@NCNTs. Furthermore, a compatible electrolyte system has been optimized by analyzing the solvation structure and carefully regulating the component in the solid electrolyte interphase (SEI) layer. Mechanistic studies demonstrate that the decomposition predominantly controlled by FSI- leads to the formation of a robust inorganic SEI layer enriched with KF, thus effectively inhibiting irreversible side reactions and major structural deterioration. Confirming our expectations, Ti3C2Tx-Co@NCNTs exhibits an impressive reversible capacity of 260 mA h g-1, even after 2000 cycles at 500 mA g-1 in 1 M KFSI (DME), surpassing most MXene-based anodes reported for PIBs. Additionally, density functional theory (DFT) calculations verify the superior electronic conductivity and lower K+ diffusion energy barriers of the novel superstructure of Ti3C2Tx-Co@NCNTs, thereby affirming the improved electrochemical kinetics. This study presents systematic evaluation methodologies for future research on MXene-based anodes in PIBs.

3.
Chem Commun (Camb) ; 59(89): 13329-13332, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37867331

RESUMO

Herein, carbon-coated MoSe2 decorated Mo2CTx MXene heterostructures (MoSe2/Mo2CTx@C) have been fabricated. Mo2CTx works as a dual-function electron/ion conductor, which not only provides high conductivity and mechanical strength, but also prevents the severe self-aggregation of few layered MoSe2 nanosheets. The high reversible capacities of 405 mA h g-1 at 100 mA g-1 after 150 cycles and 258 mA h g-1 at 2000 mA g-1 after 400 cycles could be achieved for a potassium-ion battery.

4.
Front Immunol ; 14: 1206406, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37398657

RESUMO

Pulmonary hypertension is characterized by pulmonary arterial remodeling that results in increased pulmonary vascular resistance, right ventricular failure, and premature death. It is a threat to public health globally. Autophagy, as a highly conserved self-digestion process, plays crucial roles with autophagy-related (ATG) proteins in various diseases. The components of autophagy in the cytoplasm have been studied for decades and multiple studies have provided evidence of the importance of autophagic dysfunction in pulmonary hypertension. The status of autophagy plays a dynamic suppressive or promotive role in different contexts and stages of pulmonary hypertension development. Although the components of autophagy have been well studied, the molecular basis for the epigenetic regulation of autophagy is less understood and has drawn increasing attention in recent years. Epigenetic mechanisms include histone modifications, chromatin modifications, DNA methylation, RNA alternative splicing, and non-coding RNAs, which control gene activity and the development of an organism. In this review, we summarize the current research progress on epigenetic modifications in the autophagic process, which have the potential to be crucial and powerful therapeutic targets against the autophagic process in pulmonary hypertension development.


Assuntos
Epigênese Genética , Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/genética , Metilação de DNA , Código das Histonas/genética , Autofagia/genética
5.
J Colloid Interface Sci ; 630(Pt B): 580-590, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36335777

RESUMO

Anion substitution is a valid strategy to modulate the active sites of the transition metal dichalcogenides (TMDs). Herein, a series of cobalt sulfoselenide nanomeshes (CoS2(1-x)Se2x@NC) were synthesized by calcining S/Se power with ultrathin metal-organic framework (MOFs) nanosheets. The vacancy concentration of CoS2(1-x)Se2x@NC could be adjusted through changing the ratio of S/Se precursor. Interestingly, CoS1.25Se0.75@NC electrocatalyst possesses the largest vacancy concentration as well as the optimal electrocatalytic performance. CoS1.25Se0.75@NC delivers an overpotential as low as 134 mV for hydrogen evolution reaction (HER) and 270 mV for oxygen evolution reaction (OER) at the current density of 10 mA cm -2, respectively. Furthermore, CoS1.25Se0.75@NC affords a low cell voltage of 1.67 V (at 10 mA cm-2) and outstanding cycling stability for overall water splitting reaction (more than 55 h). For HER process, theoretical calculations prove that anion vacancy not only lower the free energy barrier of H2O dissociation step but also favor the desorption step of intermediate H*. For OER process, the anion vacancies could modulate the adsorption/desorption free energy of oxygen-containing intermediates. The present work demonstrates a practical approach to modulate the vacancy concentration of cobalt sulfoselenide and provides new ideas for design of efficient non-metal electrocatalysts.

6.
J Healthc Eng ; 2022: 9494981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35222898

RESUMO

BACKGROUND: Sacubitril valsartan and valsartan are the first new drugs approved for angiotensin receptor neprilysin lysine inhibitors (ARNIs) in outpatients with chronic heart failure (CHF) and hypertension. Compared with enalapril, sacubitril valsartan and valsartan have been shown to reduce the mortality and morbidity of cardiovascular diseases. However, there is little actual evidence regarding the efficacy of ARNIs in hypertensive patients with CHF. METHODS: From January 2019 to January 2021, 60 patients with hypertension and chronic heart failure were diagnosed and treated in our hospital. The patients were randomly divided into an observation group and a control group, with 30 cases in each group. The control group was given valsartan, the observation group was given sacubitril valsartan, and both groups were treated for six months. The endothelium-dependent vasodilation (EDD) function of the brachial artery and serum nitric oxide (NO), endothelin-1 (ET-1), carotid artery intima-media thickness, and glomerular filtration, excess rate (eGFR), and left ventricular ejection fraction (LVEF) were compared between the two groups of patients before and after treatment. The serum adiponectin (APN), matrix metalloproteinase-9 (MMP-9), and brain natriuretic peptide (BNP) levels were compared before and after treatment. RESULTS: The total effective rate of treatment in the research group was higher than that in the control group (P < 0.05). After treatment, the cardiac function indexes LVESD and LVEDD of the two groups of patients were lower than before treatment, and LVEF was higher than before treatment, and the improvement rate of the treatment group was better than that of the control group (P < 0.05). After treatment, the serum APN of the two groups was higher than before treatment, the levels of MMP-9 and BNP were lower than before treatment, and the improvement rate of patients in the treatment group was better than that of patients in the control group (P < 0.05). There was no statistically significant in the levels of EDD, NO, and ET-1 of the two groups of patients before treatment (P < 0.05). After treatment, compared with the control group, the EDD function and NO level of the research group were significantly increased (P < 0.05), and the level of ET-1 was significantly reduced (P < 0.05). There was no statistically significant difference in carotid artery intima-media thickness, glomerular filtration rate, and left ventricular ejection fraction before and after treatment in the two groups (P < 0.05). CONCLUSION: In the treatment of hypertension and chronic heart failure, sacubitril valsartan can improve the clinical symptoms of patients to the greatest extent and can significantly improve the levels of LVEF, LVEDD, NT-proBNP, heart function, and other indicators. Sacubitril valsartan can increase serum APN levels, reduce MMP-9 and BNP levels, and have good clinical effects. Sacubitril valsartan has a protective effect on the vascular endothelial function of patients with hypertension and CHF. However, these results need to be confirmed in studies involving more subjects and require longer follow-up times.


Assuntos
Insuficiência Cardíaca , Hipertensão , Peptídeo Natriurético Encefálico/metabolismo , Adiponectina/farmacologia , Adiponectina/uso terapêutico , Aminobutiratos/farmacologia , Aminobutiratos/uso terapêutico , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Espessura Intima-Media Carotídea , Combinação de Medicamentos , Endotélio , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Metaloproteinase 9 da Matriz/farmacologia , Metaloproteinase 9 da Matriz/uso terapêutico , Volume Sistólico , Resultado do Tratamento , Valsartana/farmacologia , Valsartana/uso terapêutico , Função Ventricular Esquerda
7.
Can J Physiol Pharmacol ; 94(8): 900-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27409158

RESUMO

Fargesin, a bioactive neolignan isolated from magnolia plants, is widely used in the treatment of managing rhinitis, inflammation, histamine, sinusitis, and headache. To provide more biological information about fargesin, we investigated the effects of fargesin on rat aortic rings and 2-kidney, 1-clip (2K1C) hypertensive rats. In vitro, fargesin caused concentration-dependent vasorelaxation in rat isolated aortic rings induced by KCl and norepinephrine. The effect was weakened by endothelium denudation and nitric oxide (NO) synthesis inhibition. In vivo, the evolution of systolic blood pressure (SBP) was followed by weekly measurements. Angiotensin II (Ang II) and endothelin (ET) levels, NO and nitric oxide synthase (NOS), and plasma and liver oxidative stress markers were determined at the end of the experimental period. After 5 weeks of fargesin treatment, we found that fargesin treatment reduced SBP, cardiac hypertrophy, and Ang II and ET levels of hypertensive rats. Increased NOS activity and NO level were observed in fargesin-treated rats. Normalisation of plasma MDA concentrations and improvement of the antioxidant defence system in plasma and liver accompanied the antihypertensive effect of fargesin. Taken together, these results provided substantial evidences that fargesin has antihypertensive effect in 2K1C hypertensive rats via inhibiting oxidative stress and promoting NO release.


Assuntos
Anti-Hipertensivos/uso terapêutico , Benzodioxóis/uso terapêutico , Hipertensão/tratamento farmacológico , Lignanas/uso terapêutico , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Hipertensivos/farmacologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Benzodioxóis/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Hipertensão/metabolismo , Lignanas/farmacologia , Masculino , Técnicas de Cultura de Órgãos , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
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