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1.
Nano Lett ; 24(11): 3361-3368, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38446607

RESUMO

For the first time, a series of MXene (Ti3C2Tx)/Bi2WO6 Schottky junction piezocatalysts were constructed, and the piezocatalytic hydrogen evolution activity was explored. Optimal Ti3C2Tx/Bi2WO6 exhibits the highest piezocatalytic hydrogen evolution rate of 764.4 µmol g-1 h-1, which is nearly 8 times higher than that of pure Ti3C2Tx and twice as high as that of Bi2WO6. This value also surpasses that of most recently reported typical piezocatalysts. Moreover, related experimental results and density functional theory calculations reveal that Ti3C2Tx/Bi2WO6 can provide unique channels for efficient electron transfer, enhance piezoelectric properties, optimize the adsorption Gibbs free energy of water, reduce activation energy for hydrogen atoms, endow robust separation capacity of charge carrier, and restrict the electron-hole recombination rate, thus significantly promoting the efficiency of hydrogen evolution reaction. Ultimately, we have unraveled an innovative piezocatalytic mechanism. This work broadens the scope of MXene materials in a sustainable energy piezocatalysis application.

2.
Inorg Chem ; 62(16): 6428-6438, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37032488

RESUMO

Developing high-efficiency, low-cost, and earth-abundant electrocatalysts toward the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is highly desirable for boosting the energy efficiency of water splitting. Herein, we adopted an interfacial engineering strategy to enhance the overall water splitting (OWS) activity via constructing a bifunctional OER/HER electrocatalyst combining MoS2-Ni3S2 with NiFe layered double hydroxide (NiFe-LDH) on a nickel foam substrate. The NiFe-LDH/MoS2-Ni3S2/NF electrocatalyst delivers superior OER/HER activity and stability, such as low overpotentials (220 and 79 mV for OER and HER at current densities of 50 and 10 mA cm-2, respectively) and a low Tafel slope. This excellent electrocatalytic performance mainly benefits from the electronic structure modulation and synergistic effects between NiFe-LDH and MoS2-Ni3S2, which provides a high electrochemical activity area, more active sites, and strong electron interaction. Furthermore, the assembly of NiFe-LDH/MoS2-Ni3S2/NF into a two-electrode system only requires an ultra-low cell voltage of 1.50 V at a current density of 10 mA cm-2 and exhibits outstanding stability with a decay of current density of only 2.11% @50 mA cm-2 after 50 h, which is far superior to numerous other reported transition metal NiFe-LDH and MoS2-Ni3S2-based as well as RuO2||Pt-C electrocatalysts. This research highlights the rational design of heterostructures to efficiently advance electrocatalysis for water splitting applications.

3.
BMC Med ; 20(1): 437, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352434

RESUMO

BACKGROUND: Cervical squamous cell carcinoma (SCC) is known to arise through increasingly higher-grade squamous intraepithelial lesions (SILs) or cervical intraepithelial neoplasias (CINs). This study aimed to describe sequential molecular changes and identify biomarkers in cervical malignant transformation. METHODS: Multidimensional data from five publicly available microarray and TCGA-CESC datasets were analyzed. Immunohistochemistry was carried out on 354 cervical tissues (42 normal, 62 CIN1, 26 CIN2, 47 CIN3, and 177 SCC) to determine the potential diagnostic and prognostic value of identified biomarkers. RESULTS: We demonstrated that normal epithelium and SILs presented higher molecular homogeneity than SCC. Genes in the region (e.g., 3q, 12q13) with copy number alteration or HPV integration were more likely to lose or gain expression. The IL-17 signaling pathway was enriched throughout disease progression with downregulation of IL17C and decreased Th17 cells at late stage. Furthermore, we identified AURKA, TOP2A, RFC4, and CEP55 as potential causative genes gradually upregulated during the normal-SILs-SCC transition. For detecting high-grade SIL (HSIL), TOP2A and RFC4 showed balanced sensitivity (both 88.2%) and specificity (87.1 and 90.1%), with high AUC (0.88 and 0.89). They had equivalent diagnostic performance alone to the combination of p16INK4a and Ki-67. Meanwhile, increased expression of RFC4 significantly and independently predicted favorable outcomes in multi-institutional cohorts of SCC patients. CONCLUSIONS: Our comprehensive study of gene expression profiling has identified dysregulated genes and biological processes during cervical carcinogenesis. RFC4 is proposed as a novel surrogate biomarker for determining HSIL and HSIL+, and an independent prognostic biomarker for SCC.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Prognóstico , Biomarcadores Tumorais/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Expressão Gênica , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/genética , Proteína de Replicação C/genética , Proteína de Replicação C/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/genética , Displasia do Colo do Útero/patologia
4.
Micromachines (Basel) ; 14(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38004878

RESUMO

This article presents a novel approach for evaluating laser scribing quality through cross-section profiles generated from a three-dimensional optical profiler. Existing methods for assessing scribing quality only consider the width and depth of a scribe profile. The proposed method uses a cubic spline model for cross-section profiles. Two quality characteristics are proposed to assess scribing accuracy and consistency. Accuracy is measured by the ratio of the actual laser-scribed area to the target area (RA), which reflects the deviation from the desired profile. The mean square error (MSE) is a measure of how close each scribed cross-section under the same scribing conditions is to the fitted cubic spline model. Over 1370 cross-section profiles were generated under 171 scribing conditions. Two response surface polynomial models for RA and MSE were built with 18 scribing conditions with acceptable scribing depth and RA values. Both RA and MSE were considered simultaneously via contour plots. A scatter plot of RA and MSE was then used for Pareto optimization. It was found that the cross-sectional profile of a laser scribe could be accurately represented by a cubic spline model. A multivariate nonlinear regression model for RA and MSE identified pulse energy and repetition rate as the two dominant laser parameters. A Pareto optimization analysis further established a Pareto front, where the best compromised solution could be found.

5.
J Colloid Interface Sci ; 639: 343-354, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36812851

RESUMO

Piezocatalysis as an emerging technology is broadly applied in hydrogen evolution and organic pollutants degradation aspects. However, the dissatisfactory piezocatalytic activity is a severe bottleneck for its practical applications. In this work, CdS/BiOCl S-scheme heterojunction piezocatalysts were constructed and explored the performances of piezocatalytic hydrogen (H2) evolution and organic pollutants degradation (methylene orange, rhodamine B and tetracycline hydrochloride) under strain by ultrasonic vibration. Interestingly, CdS/BiOCl presents a volcano-type relationship between catalytic activity and CdS contents, namely firstly increases and then decreases with the increase of CdS content. Optimal 20 % CdS/BiOCl endows superior piezocatalytic H2 generation rate of 1048.2 µmol g-1h-1 in methanol solution, which is 2.3 and 3.4 times higher than that of pure BiOCl and CdS, respectively. This value is also much higher than the recently reported Bi-based and most of other typical piezocatalysts. Meanwhile, 5 % CdS/BiOCl delivers the highest reaction kinetics rate constant and degradation rate toward various pollutants compared with other catalysts, which also exceeds that of the previously numerous results. Improved catalytic capacity of CdS/BiOCl is mainly ascribed to the construction of S-scheme heterojunction for enhancing the redox capacity as well as inducing more effective charge carriers separation and transfer. Moreover, S-scheme charge transfer mechanism is demonstrated via electron paramagnetic resonance and Quasi-In-situ X-ray photoelectron spectroscopy measurements. Eventually, a novel piezocatalytic mechanism of CdS/BiOCl S-scheme heterojunction has been proposed. This research develops a novel pathway for designing highly efficient piezocatalysts and provides a deeper understanding in construction of Bi-based S-scheme heterojunction catalysts for energy conservation and wastewater disposal applications.

6.
Signal Transduct Target Ther ; 7(1): 317, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097006

RESUMO

Finely tuned mitogen-activated protein kinase (MAPK) signaling is important for cancer cell survival. Perturbations that push cells out of the MAPK fitness zone result in cell death. Previously, in a screen of the North China Pharmaceutical Group Corporation's pure compound library of microbial origin, we identified elaiophylin as an autophagy inhibitor. Here, we demonstrated a new role for elaiophylin in inducing excessive endoplasmic reticulum (ER) stress, ER-derived cytoplasmic vacuolization, and consequent paraptosis by hyperactivating the MAPK pathway in multiple cancer cells. Genome-wide CRISPR/Cas9 knockout library screening identified SHP2, an upstream intermediary of the MAPK pathway, as a critical target in elaiophylin-induced paraptosis. The cellular thermal shift assay (CETSA) and surface plasmon resonance (SPR) assay further confirmed the direct binding between the SHP2 and elaiophylin. Inhibition of the SHP2/SOS1/MAPK pathway through SHP2 knockdown or pharmacological inhibitors distinctly attenuated elaiophylin-induced paraptosis and autophagy inhibition. Interestingly, elaiophylin markedly increased the already-elevated MAPK levels and preferentially killed drug-resistant cells with enhanced basal MAPK levels. Elaiophylin overcame drug resistance by triggering paraptosis in multiple tumor-bearing mouse models resistant to platinum, taxane, or PARPi, suggesting that elaiophylin might offer a reasonable therapeutic strategy for refractory ovarian cancer.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Animais , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Feminino , Humanos , Macrolídeos , Camundongos , Proteínas Quinases Ativadas por Mitógeno , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética
7.
J Exp Clin Cancer Res ; 38(1): 415, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615580

RESUMO

In the original publication of this manuscript [1], Fig. 5E lower panel was incorrect due to an error in the preparation of these figures for publication. It was noticed that in the lower panel of Fig. 5E, one mouse image of ApoE-/- + PBS group (upper) was a photograph coming from ApoE-/- + BAPN pre-treatment group (lower). The corrected figure appears below. We apologize for any confusion this may have caused.

8.
J Exp Clin Cancer Res ; 37(1): 32, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29458390

RESUMO

BACKGROUND: Extracellular matrix (ECM) is a mediator of tumor progression. However, whether the alterations of the intraperitoneal ECM prior to tumor establishment affects the malignant progression of ovarian cancer remains elusive. METHODS: Apolipoprotein (ApoE) knock-out mice was used to analyze the intraperitoneal ECM alterations by quantification of the major components of ECM. ID8 cells were implanted in vivo to generate allografts and human ovarian cancer cell lines were characterized in vitro to assess the effects of ECM alterations on the malignant progression of ovarian cancer. Adhesion assay, immunochemistry, cytokines profile, proliferation assay, transwell invasion assay and western blot were used to determine the malignant phenotype of ovarian cancer cells. RESULTS: ApoE loss induced increased ECM deposition, which stimulated the adhesions of ovarian cancer cells. The adhesion-mediated focal adhesion kinase (FAK) signaling enhanced the invasive behaviors of ovarian cancer cells through activation of a ERK-MMP linkage. This ECM-induced signaling cascade was further confirmed in human ovarian cancer cell lines in vitro. Furthermore, reversal of the ECM accumulation with BAPN or abrogation of adhesion-induced ERK activation in ovarian cancer cells with MEK inhibitors (MEKi) was found to effectively delay ovarian cancer progression. CONCLUSIONS: These findings identify the FAK-ERK activation in cell/matrix adhesion in the malignant progression of ovarian cancer and the efficiency of BAPN or MEKi for tumor suppression, providing an impetus for further studies to explore the possibility of new anticancer therapeutic combinations.


Assuntos
Apolipoproteínas E/deficiência , Matriz Extracelular/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Aminopropionitrilo/farmacologia , Animais , Adesão Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Camundongos , Camundongos Knockout , Neoplasias Ovarianas/patologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral
9.
ACS Appl Mater Interfaces ; 6(21): 19318-26, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25322454

RESUMO

We report that CoNi2S4 nanosheet arrays exhibit ultrahigh specific capacitance of 2906 F g(-1) and areal capacitance of 6.39 F cm(-2) at a current density of 5 mA cm(-2), as well as good rate capability and cycling stability, and superior electrochemical performances with an energy density of 33.9 Wh kg(-1) at a power density of 409 W kg(-1) have been achieved in an assembled aqueous asymmetric supercapacitor. The CoNi2S4 nanosheet arrays were in situ grown on nickel foams by a facile two-step hydrothermal method. The formation mechanism of the CoNi2S4 nanosheet arrays was based on an anion-exchange reaction involving the pseudo Kirkendall effect. The two aqueous asymmetric supercapacitors in series using the CoNi2S4 nanosheet arrays as the positive electrodes can power four 3-mm-diameter red-light-emitting diodes. The outstanding supercapacitive performance of CoNi2S4 nanosheet arrays can be attributed to ravine-like nanosheet architectures with good mechanical and electrical contact, low crystallinity and good wettability without an annealing process, rich redox reactions, as well as high conductivity and transport rate for both electrolyte ions and electrons. Our results demonstrate that CoNi2S4 nanosheet arrays are promising electrode materials for supercapacitor applications.

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