Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Nanotechnology ; 34(18)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36669193

RESUMO

To enhance the performance of transition metal chalcogenide composite electrode material, a key point is a composite design and preparation based on the synergistic effect between the oxide and selenide materials. With a facile 'one step template-annealing' step, Ni3Se4, Ni0.6Zn0.4O and ZnO are simultaneously synthesized, by 500 °C annealing. With the increase of annealing temperature from 350 °C to 600 °C, nickel selenides change from NiSe2to Ni3Se4to NiSe. The charge storage capacity increases first and then decreases with the increase of annealing temperature, and the 500 °C annealing obtained three compound composite Ni3Se4/Ni0.6Zn0.4O/ZnO (NNZ-500) nanoparticle material displayed a high specific capacitance of 1089.2 F g-1at 1 A g-1, and excellent cycle stability of 99.8% capacitance retention after 2000 cycles at 5 A g-1. Moreover, an asymmetric supercapacitor was assembled with NNZ-500 as the positive electrode material and activated carbon as the negative electrode material. This kind of asymmetric supercapacitor demonstrated a high energy density of 53.4 Wh kg-1at 819.0 W kg-1, and cycle stability with 98.6% capacitance retention after 2000 cycles. This material preparation approach provides great potential for the future development of high performance transition metal composite electrode materials in energy storage applications.

2.
Environ Res ; 233: 116387, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37302743

RESUMO

Medium chain fatty acids (MCFA) generation is attracting growing interest due to fossil fuel depletion. To promote the production of MCFA, especially caproate, hydrochloric acid pretreated activated carbon (AC) was introduced into chain elongation fermentation. In this study, the role of pretreated AC on caproate production was investigated using lactate and butyrate as electron donor and electron acceptor, respectively. The results showed that AC did not improve the chain elongation reaction at beginning but promoted the caproate production at later stage. The addition of 15 g/L AC facilitated reactor reaching the peak of caproate concentration (78.92 mM), caproate electron efficiency (63.13%), and butyrate utilization rate (51.88%). The adsorption experiment revealed a positive correlation between the adsorption capacity of pretreated AC and the concentration as well as the carbon chain length of carboxylic acids. Moreover, the adsorption of undissociated caproate by pretreated AC contributed to a mitigated toxicity towards microorganisms, thereby facilitating the production of MCFA. Microbial community analysis revealed an increasing enrichment of key functional chain elongation bacteria, including Eubacterium, Megasphaera, Caproiciproducens, and Pseudoramibacter, but a suppression on acrylate pathway microorganism Veillonella, as the dosage of pretreated AC increasing. The findings of this study demonstrated the substantial impact of the adsorption effect of acid-pretreated AC on promoting caproate production, which would aid to the development of more efficient caproate production process.


Assuntos
Caproatos , Ácido Clorídrico , Carvão Vegetal , Ácido Láctico , Adsorção , Ácidos Graxos , Fermentação , Butiratos , Reatores Biológicos
3.
J Med Chem ; 67(5): 3321-3338, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38363069

RESUMO

Immunotherapy targeting the toll-like receptor 7 (TLR7) is a promising strategy for cancer treatment. Herein, we describe the design and synthesis of a series of imidazoquinoline-based TLR7 agonists and assess NF-κB pathway activation using HEK-Blue hTLR7 cells to identify the most potent small-molecule TLR7 agonist, SMU-L11 (EC50 = 0.024 ± 0.002 µM). In vitro experiments demonstrated that SMU-L11 specifically activated TLR7, resulting in recruitment of the MyD88 adaptor protein and activation of the NF-κB and MAPK signaling pathways. Moreover, SMU-L11 was found to exert immune-enhancing effects by significantly inducing the secretion of proinflammatory cytokines in murine dendritic cells, macrophages, and human peripheral blood mononuclear cells while promoting M1 macrophage polarization. In vivo studies using a B16-F10 mouse tumor model showed that SMU-L11 significantly enhanced immune cell activation and augmented CD4+ T and CD8+ T-cell proliferation, directly killing tumor cells and inhibiting tumor growth.


Assuntos
Melanoma , Humanos , Animais , Camundongos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , NF-kappa B/metabolismo , Receptor 7 Toll-Like/metabolismo , Microambiente Tumoral , Leucócitos Mononucleares/metabolismo , Adjuvantes Imunológicos/metabolismo
4.
Microsc Res Tech ; 86(8): 1057-1066, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37078746

RESUMO

In situ liquid cell electron microscopy (LC-EM) is a powerful platform for real time nanoscale imaging of liquid systems. In situ liquid cell scanning electron microscopy (LC-SEM) as a relatively low cost and potentially more convenient characterization method, has not been as widely used as compared to in situ liquid cell transmission electron microscopy (LC-TEM). This paper reports a real time high resolution and comprehensive characterization of Au nanoparticles (NPs) and nanoparticle clusters (NPCs), which are surface-decorated with cetyltrimethylammonium bromide (CTAB), in an oleic acid (OA) emulsion system with LC-SEM. Single NP resolution images are routinely collected with both secondary electron (SE) and backscattered electron (BSE) imaging modes, with different SEM systems. Energy dispersive spectroscopy (EDS) mapping data clearly demonstrates the single particle level chemical element distributions, particle stacking structure, as well as the preferred distribution of OA molecules on the Au particle surfaces. Moreover, both liquid droplet growth and particle motions are observed with LC-SEM, among which, ways for faster tracking the single particle level dynamic motion behavior of Au NPs and NPCs are explored. We expect that our work will bring new insight of high resolution and fast analysis in a broad range of materials in liquid with LC-SEM.

5.
Chem Sci ; 13(8): 2324-2330, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35310505

RESUMO

Leucine aminopeptidase (LAP) is involved in tumor cell proliferation, invasion, and angiogenesis, and is a well-known tumor marker. In recent years, chemiluminescence has been widely used in the field of biological imaging, due to it resulting in a high sensitivity and excellent signal-to-noise ratio. Here, we report the design, synthesis, and evaluation of the first LAP-activated chemiluminescent probe for LAP detection and imaging. The probe initially had no chemiluminescence but produced an extremely strong chemiluminescence after the release of the dioxetane intermediate in the presence of LAP. The probe had high selectivity over other proteases and higher signal-to-noise ratios than commercial fluorophores. Real-time imaging results indicated that the chemiluminescence was remarkably enhanced at the mice tumor site after the probe was injected. Furthermore, the chemiluminescence of this probe in the cancerous tissues of patients was obviously improved compared to that of normal tissues. Taken together, this study has developed the first LAP-activable chemiluminescent probe, which could be potentially used in protein detection, disease diagnosis, and drug development.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA