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1.
Angew Chem Int Ed Engl ; 62(32): e202306420, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37264717

RESUMO

Sluggish oxygen evolution kinetics and serious charge recombination restrict the development of photoelectrochemical (PEC) water splitting. The advancement of novel metal-organic frameworks (MOFs) catalysts bears practical significance for improving PEC water splitting performance. Herein, a MOF glass catalyst through melting glass-forming cobalt-based zeolitic imidazolate framework (Co-ag ZIF-62) was introduced on various metal oxide (MO: Fe2 O3 , WO3 and BiVO4 ) semiconductor substrates coupled with NiO hole transport layer, constructing the integrated Co-ag ZIF-62/NiO/MO photoanodes. Owing to the excellent conductivity, stability and open active sites of MOF glass, Co-ag ZIF-62/NiO/MO photoanodes exhibit a significantly enhanced photoelectrochemical water oxidation activity and stability in comparison to pristine MO photoanodes. From experimental analyses and density functional theory calculations, Co-ag ZIF-62 can effectively promote charge transfer and separation, improve carrier mobility, accelerate the kinetics of oxygen evolution reaction (OER), and thus improve PEC performance. This MOF glass not only serves as an excellent OER cocatalyst on tunable photoelectrodes, but also enables promising opportunities for PEC devices for solar energy conversion.

2.
Br J Nutr ; 127(12): 1868-1877, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34308819

RESUMO

DNA methylation is one of the most important epigenetic modifications in breast cancer (BC) development, and long-term dietary habits can alter DNA methylation. Cadherin-4 (CDH4, a member of the cadherin family) encodes Ca2+-dependent cell-cell adhesion glycoproteins. We conducted a case-control study (380 newly diagnosed BC and 439 cancer-free controls) to explore the relationship of CDH4 methylation in peripheral blood leukocyte DNA (PBL DNA), as well as its combined and interactive effects with dietary factors on BC risk. A case-only study (335 newly diagnosed BC) was conducted to analyse the association between CDH4 methylation in breast tissue DNA and dietary factors. CDH4 methylation was detected using quantitative methylation-specific PCR. Unconditional logistic regressions were used to analyse the association of CDH4 methylation in PBL DNA and BC risk. Cross-over analysis and unconditional logistic regression were used to calculate the combined and interactive effects between CDH4 methylation in PBL DNA and dietary factors in BC. CDH4 hypermethylation was significantly associated with increased BC risk in PBL DNA (ORadjusted (ORadj) = 2·70, (95 % CI 1·90, 3·83), P < 0·001). CDH4 hypermethylation also showed significant combined effects with the consumption of vegetables (ORadj = 4·33, (95 % CI 2·63, 7·10)), allium vegetables (ORadj = 7·00, (95 % CI 4·17, 11·77)), fish (ORadj = 7·92, (95 % CI 3·79, 16·53)), milk (ORadj = 6·30, (95 % CI 3·41, 11·66)), overnight food (ORadj = 4·63, (95 % CI 2·69, 7·99)), pork (ORadj = 5·59, (95 % CI 2·94, 10·62)) and physical activity (ORadj = 4·72, (95 % CI 2·87, 7·76)). Moreover, consuming milk was significantly related with decreased risk of CDH4 methylation (OR = 0·61, (95 % CI 0·38, 0·99)) in breast tissue. Our findings may provide direct guidance on the dietary intake for specific methylated carriers to decrease their risk for developing BC.


Assuntos
Metilação de DNA , Neoplasias , Animais , Estudos de Casos e Controles , Epigênese Genética , Ingestão de Alimentos , Modelos Logísticos , Fatores de Risco
3.
J Enzyme Inhib Med Chem ; 32(1): 1282-1290, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29072109

RESUMO

Twenty-three novel resveratrol-based cinnamic ester hybrids were designed and synthesized. All the compounds were evaluated for their anti-inflammatory activity using RAW264.7 cells. Among them, compound D15 was found to be the most potent one in inhibiting NO production in LPS-stimulated RAW264.7 cells. The further study indicated that compound D15 could suppress expression of proteins iNOS, COX-2, p-p65, and p-IκB LPS-induced. Immunofluorescence further revealed compound D15 could reduce activation p65 in nuclei. All the results indicated that the anti-inflammatory activity of title compound may partly due to its inhibitory effect on the NF-κB signaling pathway.


Assuntos
Cinamatos/síntese química , Cinamatos/farmacologia , Ésteres/síntese química , Ésteres/farmacologia , Macrófagos/efeitos dos fármacos , Estilbenos/síntese química , Estilbenos/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Western Blotting , Células Cultivadas , Cinamatos/química , Cristalografia por Raios X , Ésteres/química , Macrófagos/imunologia , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Células RAW 264.7 , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/química
4.
Angew Chem Int Ed Engl ; 54(29): 8480-4, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26068934

RESUMO

The photochemical conversion of carbon dioxide provides a straightforward and effective strategy for the highly efficient production of solar fuels with high solar-light utilization efficiency. However, the high recombination rate of photoexcited electron-hole (e-h) pairs and the poor photostability have greatly limited their practical applications. Herein, a practical strategy is proposed to facilitate the separation of e-h pairs and enhance the photostability in a semiconductor by the use of a Schottky junction in a bimetal-graphene-semiconductor stack array. Importantly, Au-Cu nanoalloys (ca. 3 nm) supported on a 3D ultrathin graphene shell encapsulating a p-type Cu2O coaxial nanowire array promotes the stable photochemical reduction of CO2 to methanol by the synergetic catalytic effect of interfacial modulation and charge-transfer channel design. This work provides a promising lead for the development of practical catalysts for sustainable fuel synthesis.

5.
PLoS One ; 19(3): e0293818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507430

RESUMO

The innovation in technology and economic growth, which are brought about by digital transformation in enterprises, will inevitably impact their performance in the capital market. Using a sample of Chinese A-share listed companies from 2012 to 2021, this study extensively examines the impact, mechanism, and economic consequences of enterprises digital transformation on stock liquidity. The research reveals that enterprises digital transformation can significantly improve stock liquidity. From the perspective of corporate governance, a further analysis indicates that the digital transformation of enterprises can improve stock liquidity by three mechanisms: easing financing constraints, improving the quality of internal control, and enhancing information disclosure. The results of the heterogeneity analysis indicate that the digital transformation of enterprises, combined with a high level of financial technology, developed financial markets, and policy guidance, has a significantly more significant effect on improving stock liquidity. The analysis of economic consequences reveals that the digital transformation of enterprises can lower the risk of a stock price crash and enhance the accuracy of analysts' forecasts, primarily by improving stock liquidity. This study offers empirical evidence from a micro-mechanism perspective that elucidates the spillover effect of enterprise digital transformation on the capital market. It provides insight into the impact of enterprise digital transformation on stock liquidity and offers theoretical guidance to promote the adoption of enterprise digital transformation across different countries and enhance stock liquidity in the capital market.

6.
Phys Chem Chem Phys ; 15(37): 15660-8, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-23942887

RESUMO

Highly efficient hydrogen production can be achieved by three-dimensional (3D) architectures of CdS quantum dots (QDs) incorporated in the porous assembly of marigold-like ZnIn2S4 heterostructures coupled with graphene, leading to an efficient electron transfer between them and the enhancement of the ZnIn2S4 photostability. The as-prepared samples were characterized by X-ray diffraction, electron microscopy, Brunauer-Emmett-Teller analysis, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance absorption spectra, and photoluminescence spectra. Especially, 3 wt% CdS QDs decorated ZnIn2S4 heteroarchitectures showed a high rate of H2-production at 1.9 mmol h(-1), more 2.7 times than that of ZnIn2S4. The rate was further increased to 2.7 mmol h(-1) with a high quantum efficiency of 56% using the 3 wt% CdS QDs decorated ZnIn2S4 composites coupled with 1 wt% graphene (about 4 times higher than that of the pure ZnIn2S4). Moreover, the CdS QDs/graphene/ZnIn2S4 exhibited strong durability due to the high hydrothermal stability of the flower-like structure and the inhibition of CdS leaching owing to its strong interaction with ZnIn2S4. The excellent photocatalytic performance is ascribed to the enhanced light absorption and the improved separation of photogenerated carriers. This finding highlights the validity of 3D semiconductor heterostructures as effective building blocks for exploring efficient visible-light-active photocatalysts.

7.
Eur J Med Chem ; 103: 185-90, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26352677

RESUMO

Using a fragment-based drug design strategy, two biomedical interesting fragments, resveratrol and coumarin were linked to design a series of novel human monoamine oxidase (hMAO) inhibitors with a scaffold of 3-((E)-3-(2-((E)-styryl)phenyl)acryloyl)-2H-chromen-2-one, which demonstrated a very interesting selectivity profile against hMAO-A and hMAO-B: some compounds with this scaffold are selective hMAO-A inhibitors, whereas some are selective hMAO-B inhibitors. The small changes in the substituents of the coumarin moiety led to this interesting selectivity profile. The most potent selective hMAO-B inhibitor D7 has a selectivity ratio of 20.93, with an IC50 value of 2.78 µM, similar or better than selegiline (IC50 = 2.89 µM), a selective hMAO-B inhibitor currently in the market for the treatment of Parkinson's disease. Our modeling study indicates that Tyr 326 of hMAO-B (or corresponded Ile 335 of hMAO-A) may be the determinant for the specificity of these compounds. The selectivity profile of compounds reported herein suggests that we can further develop both selective hMAO-A and hMAO-B inhibitors based on this novel scaffold.


Assuntos
Cromonas/farmacologia , Desenho de Fármacos , Inibidores da Monoaminoxidase/síntese química , Inibidores da Monoaminoxidase/farmacologia , Monoaminoxidase/metabolismo , Estilbenos/química , Cromonas/síntese química , Cromonas/química , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores da Monoaminoxidase/química , Resveratrol , Relação Estrutura-Atividade
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