Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Adv Sci (Weinh) ; 11(32): e2307571, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923859

RESUMO

The demand for low-dimensional ferroelectric devices is steadily increasing, however, the thick substrates in epitaxial films impede further size miniaturization. Freestanding films offer a potential solution by eliminating substrate constraints. Nevertheless, it remains an ongoing challenge to improve the stability in thin and fragile freestanding films under strain and temperature. In this work, the structure and ferroelectric order of freestanding PbTiO3 (PTO) films are investigated under continuous variation of the strain and temperature using nondestructive optical second harmonic generation (SHG) technique. The findings reveal that there are both out-of-plane and in-plane domains with polarization along out-of-plane and in-plane directions in the orthorhombic-like freestanding PTO films, respectively. In contrast, only out-of-plane domains are observed in the tetragonal epitaxial PTO films. Remarkably, the ferroelectricity of freestanding PTO films is strengthened under small uniaxial tensile strain from 0% up to 1.66% and well-maintained under larger biaxial tensile strain up to 2.76% along the [100] direction and up to 4.46% along the [010] direction. Moreover, a high Curie temperature of 630 K is identified in 50 nm thick freestanding PTO films by wide-temperature-range SHG. These findings provide valuable understanding for the development of the next-generation electronic nanodevices with flexibility and thermostability.

2.
ESC Heart Fail ; 11(5): 2684-2693, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38661235

RESUMO

The study aims to evaluate whether rhythm control by catheter ablation is superior to medical therapy for the patients with atrial fibrillation (AF) and heart failure (HF). The literatures were searched by using PubMed, Cochrane Library, Embase, and Web of Science databases up to 12 October 2023. The randomized controlled trials (RCTs) comparing rhythm control using catheter ablation vs. medical therapy in AF patients with HF were pooled. The primary outcomes included all-cause mortality, HF re-hospitalization, and stroke, and the secondary outcomes included left ventricular ejection fraction (LVEF), atrial tachyarrythmia recurrence, quality of life (Minnesota Living with Heart Failure Questionnaire score, MLHFQ score), 6 min walking distance (6MWD), the level of N-terminal B-type natriuretic peptide precursor (NT-proBNP), and adverse events. Nine RCTs involving in 2293 patients met the inclusion criteria. Compared with medical therapy, catheter ablation reduced all-cause mortality [10.07% (121/1201) vs. 15.26% (175/1147), risk ratio (RR):0.60, 95% confidence interval (CI): 0.48-0.74, P < 0.00001, I2 = 0%] and the rate of HF re-hospitalization (RR: 0.65, P = 0.02, 95% CI: 0.45 to 0.94, I2 = 74%), but had no obvious difference in incidence of stroke (RR: 0.67, P = 0.27, 95% CI: 0.32 to 1.38, I2 = 0%). Catheter ablation enhanced LVEF [mean difference (MD), 6.26%, P < 0.00001, I2 = 89%], reduced AT recurrence (RR: 0.37, P < 0.00001, 95% CI: 0.26 to 0.52, I2 = 89%), improved the quality of life (MLHFQ score) (MD: -6.83, P = 0.003, I2 = 67%), elevated 6MWD (MD: 15.92, P = 0.006, I2 = 76%), and diminished the level NT-proBNP (MD: -44.19, P < 0.00001, I2 = 75%), but had no significant difference in adverse events [25.81% (310/1201) vs. 30.25% (347/1147), RR: 0.81, 95% CI: 0.65-1.01, P = 0.06, I2 = 55%]. Catheter ablation as rhythm control strategy substantially enhances the survival rate, reduces HF re-hospitalization, increases the rate of sinus rhythm maintenance, improves the left ventricular function and the quality of life for AF patients with HF, and has similar safety, compared with medical therapy. The rhythm control by catheter ablation may be a better strategy for the AF patients with HF.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Insuficiência Cardíaca , Humanos , Fibrilação Atrial/cirurgia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/complicações , Fibrilação Atrial/terapia , Ablação por Cateter/métodos , Saúde Global , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/complicações , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
3.
Nat Commun ; 15(1): 3257, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627413

RESUMO

Biological nervous system outperforms in both dynamic and static information perception due to their capability to integrate the sensing, memory and processing functions. Reconfigurable neuromorphic transistors, which can be used to emulate different types of biological analogues in a single device, are important for creating compact and efficient neuromorphic computing networks, but their design remains challenging due to the need for opposing physical mechanisms to achieve different functions. Here we report a neuromorphic electrolyte-gated transistor that can be reconfigured to perform physical reservoir and synaptic functions. The device exhibits dynamics with tunable time-scales under optical and electrical stimuli. The nonlinear volatile property is suitable for reservoir computing, which can be used for multimodal pre-processing. The nonvolatility and programmability of the device through ion insertion/extraction achieved via electrolyte gating, which are required to realize synaptic functions, are verified. The device's superior performance in mimicking human perception of dynamic and static multisensory information based on the reconfigurable neuromorphic functions is also demonstrated. The present study provides an exciting paradigm for the realization of multimodal reconfigurable devices and opens an avenue for mimicking biological multisensory fusion.

4.
Arch Pharm (Weinheim) ; 348(11): 757-775, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26462013

RESUMO

The androgen receptor (AR), a ligand-dependent transcription factor that regulates the expression of a series of downstream target genes after the binding of androgens, has been a target for the discovery of drugs used to treat prostate cancer. Prostate cancer always progresses to castration-resistant prostate cancer after a period of androgen deprivation therapy. Thus, developing potent androgen receptor antagonists for the therapy of castration-resistant prostate cancer possesses great significance. This review summarizes the preclinical development of androgen receptor antagonists, conventional androgen receptor antagonists that competitively bind to the ligand binding domain of the androgen receptor and coactivator antagonists of the androgen receptor, including both activation function-2 antagonists and binding function-3 antagonists. We hope that this review can help other researchers find new scaffolds and sites for the treatment of prostate cancer.

5.
Drug Discov Ther ; 8(3): 110-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25031042

RESUMO

A new series of 1,5-disubstituted indolin-2,3-diones was synthesized and their inhibition of the growth of a human acute promyelocytic leukemia (HL-60) cell line was evaluated. These compounds had promising inhibition of HL-60 cell growth in vitro. Results indicated that compounds with a benzyl substituent at the N-1 position on the indolin-2,3-dione ring had more potent antiproliferative activity than those with a (4-fluorobenzyl) amino-2-oxoethyl substituent at the N-1 position. Among the compounds synthesized, compound 8l inhibited half of cell growth at a concentration of 0.07 µM and compound 8p did so at a concentration of 0.14 µM. These compounds may serve as lead compounds for further optimization in order to develop novel anticancer agents.


Assuntos
Antineoplásicos/síntese química , Indóis/síntese química , Antineoplásicos/farmacologia , Células HL-60 , Humanos , Indóis/farmacologia
6.
Mol Cancer Ther ; 12(9): 1837-47, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23804706

RESUMO

Ethacrynic acid, a diuretic, inhibits glutathione S-transferase P1-1 (GSTP1-1) activity and induces cell death in malignant cells at high concentrations. To improve ethacrynic acid activity, ethacrynic acid oxadiazole analogs 6s and 6u were synthesized. Although both compounds have greater antiproliferative effects than ethacrynic acid in human HL-60 cells, 6u has a reduced ability to inhibit GSTP1-1 activity. The mechanisms of both 6s- and 6u-induced cell death as well as the role of GSTP1-1 in their actions were studied. Both 6s and 6u equally induced apoptosis in HL-60 cells due to the activation of caspase-3, -9, and -8, which was correlated with the downregulation of antiapoptotic proteins c-FLIP, Mcl-1, and XIAP. The caspase inhibitor Z-VAD-FMK blocked the reduction of XIAP, but not of c-FLIP and Mcl-1, in 6s-treated cells. The reduction of c-FLIP and Mcl-1 by 6s was not blocked by the proteasomal inhibitor MG132, but was correlated with inhibition of the phosphorylation of extracellular signal-regulated kinase (ERK) and eIF4E. Both 6s and 6u decreased the intracellular glutathione (GSH) levels. N-acetylcysteine blocked reduction in the levels of Mcl-1, c-FLIP, and intracellular GSH as well as apoptosis in HL-60 cells treated by either compound. Silencing of GSTP1-1 in K562 cells sensitized, but overexpression of GSTP1-1 in Raji cells blocked, apoptosis induction by either compound. GSH conjugation at the methylene group abrogated the ability of inducing apoptosis. These data suggest that the methylene group plays an important role in the downregulation of c-FLIP and Mcl-1 proteins and apoptosis induction, which is inactivated by GSTP1-1 by forming GSH conjugates.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Inibidores Enzimáticos/farmacologia , Ácido Etacrínico/análogos & derivados , Glutationa S-Transferase pi/metabolismo , Leucemia Mieloide/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Oxidiazóis/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Apoptose/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Caspases/análise , Caspases/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Ácido Etacrínico/química , Ácido Etacrínico/farmacologia , Regulação Leucêmica da Expressão Gênica , Glutationa/metabolismo , Glutationa S-Transferase pi/antagonistas & inibidores , Células HL-60 , Humanos , Células Jurkat , Células K562 , Leupeptinas/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Oxidiazóis/química , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA