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1.
Small ; 20(24): e2309647, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38240559

RESUMO

1T-MoSe2 is recognized as a promising anode material for sodium-ion batteries, thanks to its excellent electrical conductivity and large interlayer distance. However, its inherent thermodynamic instability often presents unparalleled challenges in phase control and stabilization. Here, a molecular intercalation strategy is developed to synthesize thermally stable 1T-rich MoSe2, covalently bonded to an intercalated carbon layer (1TR/2H-MoSe2@C). Density functional theory calculations uncover that the introduced ethylene glycol molecules not only serve as electron donors, inducing a reorganization of Mo 4d orbitals, but also as sacrificial guest materials that generate a conductive carbon layer. Furthermore, the C─Se/C─O─Mo bonds encourage strong interfacial electronic coupling, and the carbon layer prevents the restacking of MoSe2, regulating the maximum 1T phase to an impressive 80.3%. Consequently, the 1TR/2H-MoSe2@C exhibits an extraordinary rate capacity of 326 mAh g-1 at 5 A g-1 and maintains a long-term cycle stability up to 1500 cycles, with a capacity of 365 mAh g-1 at 2 A g-1. Additionally, the full cell delivers an appealing energy output of 194 Wh kg-1 at 208 W kg-1, with a capacity retention of 87.3% over 200 cycles. These findings contribute valuable insights toward the development of innovative transition metal dichalcogenides for next-generation energy storage technologies.

2.
Appl Opt ; 63(16): 4245-4250, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856599

RESUMO

A novel, to our knowledge, L-band erbium-doped fiber laser, utilizing a nonlinear optical loop mirror (NOLM) as a mode-locker, is presented in this study. Through precise adjustments of the polarization controllers (PCs), the laser achieves the generation of rectangular pulses with distinct single wavelengths, λ 1=1593n m and λ 2=1571n m, as well as dual-wavelength operation. The laser's operational mode can extend further to include harmonic mode-locking (HML). Furthermore, the investigation reveals the emergence of trapezoidal pulses and low-peak-power rectangular pulses within proximity of the conventional rectangular pulses. Notably, the evolutions of these low-peak-power pulses with the pump power also adhere to the peak power clamping (PPC) effect. Remarkably, the relative positioning of these pulses remains consistent across varying pump power levels or harmonic orders. Intriguingly, the evolution of the trapezoidal pulse with respect to pump power stands in stark contrast to that of the h-shaped pulse.

3.
Angew Chem Int Ed Engl ; : e202407770, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934232

RESUMO

Magnesium metal batteries (MMBs), recognized as promising contenders for post-lithium battery technologies, face challenges such as uneven magnesium (Mg) plating and stripping behaviors, leading to uncontrollable dendrite growth and irreversible structural damage. Herein, we have developed a Mg foil featuring prominently exposed (002) facets and an architecture of nanosheet arrays (termed (002)-Mg), created through a one-step acid etching method. Specifically, the prominent exposure of Mg (002) facets, known for their inherently low surface and adsorption energies with Mg atoms, not only facilitates smooth nucleation and dense deposition but also significantly mitigates side reactions on the Mg anode. Moreover, the nanosheet arrays on the surface evenly distribute the electric field and Mg ion flux, enhancing Mg ion transfer kinetics. As a result, the fabricated (002)-Mg electrodes exhibit unprecedented long-cycle performance, lasting over 6000 h (> 8 months) at a current density of 3 mA cm-2 for a capacity of 3 mAh cm-2. Furthermore, the corresponding pouch cells equipped with various electrolytes and cathodes demonstrate remarkable capacity and cycling stability, highlighting the superior electrochemical compatibility of the (002)-Mg electrode. This study provides new insights into the advancement of durable MMBs by modifying the crystal structure and morphology of Mg.

4.
Environ Toxicol ; 38(8): 1874-1890, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37148176

RESUMO

Hydroquinone (HQ), one of the main active metabolites of benzene in vivo, 7is commonly used as a surrogate for benzene in in vitro studies and has been shown to be cytotoxic. The aim of this study was to investigate the role of endoplasmic reticulum stress (ERS) in HQ-induced autophagy and apoptosis in human lymphoblastoid cells (TK6) and how activating transcription factor 6 (ATF-6) is involved. We treated TK6 cells with HQ to establish a cytotoxicity model and found that HQ induced cellular ERS, autophagy and apoptosis by Western blot, flow cytometry and transmission electron microscopy. In addition, inhibition of both reactive oxygen species (ROS) and ERS inhibited cellular autophagy and apoptosis, suggesting that ERS may be induced by ROS, which in turn affects autophagy and apoptosis. Our study also found that HQ could inhibit ATF6 expression and mTOR activation. Knockdown of ATF6 enhanced autophagy and apoptosis levels and further inhibited mTOR activation; activation of ATF6 by AA147 enhanced cellular activity, suggesting that ATF6 may affect cellular autophagy and apoptosis through mTOR. In conclusion, our data suggest that ROS mediated ERS may promote autophagy and apoptosis by inhibiting ATF6-mTOR pathway after HQ treatment of TK6 cells.


Assuntos
Fator 6 Ativador da Transcrição , Hidroquinonas , Humanos , Hidroquinonas/toxicidade , Fator 6 Ativador da Transcrição/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Benzeno , Serina-Treonina Quinases TOR/metabolismo , Estresse do Retículo Endoplasmático , Apoptose/fisiologia , Autofagia
5.
Ecotoxicol Environ Saf ; 241: 113757, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35714482

RESUMO

Reprogramming of cellular metabolism is a vital event during tumorigenesis. The role of glycolysis in malignant progression promoted by hydroquinone (HQ), one of the metabolic products of benzene, remains to be understood. Recently, we reported the overexpression of sirtuin 1 (SIRT1) in HQ-enhanced malignant progression of TK6 cells and hypothesized that SIRT1 might contribute to glycolysis and favor tumorigenesis. Our data showed that acute exposure of TK6 cells to HQ for 48 h inhibited glycolysis, as indicated by reduction in glucose consumption, lactate production, hexokinase activity, and the expression of SIRT1 and glycolytic enzymes, including HIF-1α, hexokinase-2 (HK-2), ENO-1, glucose transporter 1 (Glut-1), and lactic dehydrogenase A (LDHA). Knockdown of SIRT1 or inhibition of glycolysis using the glycolytic inhibitor 2-deoxy-D-glucose (2-DG) downregulated the levels of SIRT1 and glycolytic enzymes and significantly enhanced HQ-induced cell apoptosis, although knockdown of SIRT1 or 2-DG alone had little effect on apoptosis. Furthermore, immunofluorescence and Co-IP assays demonstrated that SIRT1 regulated the expression of HK-2, and HQ treatment caused a decrease in SIRT1 and HK-2 binding to mitochondria. Importantly, we found that glycolysis was promoted with increasing HQ treatment weeks. Long-term HQ exposure increased the expression of SIRT1 and several glycolytic enzymes and promoted malignant cell progression. Moreover, compared with the PBS group, glucose consumption and lactate production increased after 10 weeks of HQ exposure, and the protein levels of SIRT1 and HK-2 were increased after 15 weeks of HQ exposure, while those of Glut-1, ENO-1, and LDHA were elevated. In addition, SIRT1 knockdown HQ 19 cells exhibited decreased lactate production, glucose consumption, glycolytic enzymes expression, cell growth, and tumor formation in nude mice. Our findings identify the high expression of SIRT1 as a strong oncogenic driver that positively regulates HK-2 and promotes glycolysis in HQ-accelerated malignant progression of TK6 cells.


Assuntos
Hexoquinase , Sirtuína 1 , Animais , Carcinogênese , Glucose , Glicólise , Hexoquinase/genética , Hexoquinase/metabolismo , Humanos , Hidroquinonas/toxicidade , Lactatos , Camundongos , Camundongos Nus , Sirtuína 1/genética , Sirtuína 1/metabolismo
6.
BMC Med Imaging ; 21(1): 43, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685388

RESUMO

BACKGROUND: The purpose of this study was to investigate the relationship between breast density, age, and mammographic lesion type among Chinese breast cancer patients included in a large clinical dataset. METHODS: A review of mammographic images acquired between July 2014 and June 2017 from a total of 9716 retrospectively registered breast cancer patients was conducted. Mammographic breast density was defined according to the American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS) 4-class density rating. Mammographic lesion types were defined according to the ACR BI-RADS, including mass, mass with calcifications, calcifications, architectural distortion/asymmetries, and architectural distortion/asymmetries with calcifications. Three experienced breast radiologists interpreted all mammograms. The chi-square (χ2) test and Pearson correlation analyses were performed to assess the relationship between breast density, age, and mammographic lesion type. RESULTS: A significant inverse relationship was observed between the BI-RADS breast density rating given by radiologists and patient age (r = - 0.521, p < 0.01). The breast density distribution in breast cancer patients from China reversed at the age of 55 years, and exhibited one age peak in the age 55-59 year group. The percentage of lesions with calcifications decreased with increasing age (p < 0.01), and increased with increasing breast density (p < 0.01). CONCLUSIONS: In general, we identified a relationship between patient breast density, age, and mammographic lesion type. This finding may provide a basis for clinical diagnoses and support development of breast cancer screening programs in China.


Assuntos
Densidade da Mama/etnologia , Neoplasias da Mama/patologia , Mamografia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , China , Conjuntos de Dados como Assunto , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
8.
ACS Appl Mater Interfaces ; 15(4): 5172-5179, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36650087

RESUMO

CuO has been regarded as a promising catalyst for the electrochemical reduction of nitrate (NO3-RR) to ammonium (NH3); however, the intrinsic activity is greatly restricted by its poor electrical property. In this work, self-supported Zn-doped CuO nanosheet arrays (Zn-CuO NAs) are synthesized for NO3-RR, where the Zn dopant regulates the electronic structure of CuO to significantly accelerate the interfacial charge transfer and inner electron transport kinetics. The Zn-CuO NAs are constructed by a one-step etching of commercial brass (Cu64Zn36 alloy) in 0.1 M NaOH solution, which experiences a corrosion-oxidation-reconstruction process. Initially, the brass undergoes a dealloying procedure to produce nanosized Cu, which is immediately oxidized to the Cu2O unit with a low valence state. Subsequently, Cu2O is further oxidized to the CuO unit and reconstructed into nanosheets with the coprecipitation of Zn2+. For NO3-RR, Zn-CuO NAs show a high NH3 production rate of 945.1 µg h-1 cm-2 and a Faradaic efficiency of up to 95.6% at -0.7 V in 0.1 M Na2SO4 electrolyte with 0.01 M NaNO3, which outperforms the majority of the state-of-the-art catalysts. The present work offers a facile yet very efficient strategy for the scale-up synthesis of Zn-CuO NAs for high-performance NH3 production from NO3-RR.

9.
Toxicol Lett ; 373: 132-140, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36442682

RESUMO

Aflatoxin B1 (AFB1) is a human procarcinogen known to be activated by cytochrome P450 (CYP) 1A2 and 3A4. In a previous study AFB1 caused chromosomal rearrangement in a yeast strain genetically engineered for stably expressing human CYP1B1. Yet, further verification of the effect of AFB1 in human cells, a potential role of the aryl hydrocarbon receptor (AhR), and CYP1B1-catalyzed AFB1 metabolism remain unidentified. In this study, a human hepatocyte (L-02) line and a human lymphoblastoid (TK6) cell line were genetically engineered for the expression of human CYP1B1, producing L-02-hCYP1B1 and TK6-hCYP1B1, respectively. They were exposed to AFB1 and analyzed for the formation of micronucleus and elevation of γ-H2AX (indicating double-strand DNA breaks); the metabolites formed by CYP1B1 from AFB1 after incubation of AFB1 with human CYP1B1 isoenzyme microsomes were determined by LC-MS. The results showed significantly more potent induction of micronucleus by AFB1 in L-02-hCYP1B1 and TK6-hCYP1B1 than in the parental (L-02 and TK6) cells, and the effects were reduced by (E)- 2,3',4,5'-tetramethoxystilbene, a specific CYP1B1 inhibitor. In the AFB1- CYP1B1 microsomes incubations AFM1, a known stable metabolite of AFB1, was detected. Moreover, in L-02 and TK6 cells, AFB1 apparently increased the protein levels of AhR, ANRT and CYP1B1, and caused the nuclear translocation of AhR and ARNT, the latter effect being blocked by BAY-218 (an inhibitor of AhR). In conclusion, this study indicates that human CYP1B1 is capable of metabolically activating AFB1 through the AhR signaling pathway.


Assuntos
Aflatoxina B1 , Receptores de Hidrocarboneto Arílico , Humanos , Aflatoxina B1/toxicidade , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Microssomos/metabolismo , Linhagem Celular
10.
Adv Mater ; 35(48): e2307017, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37821238

RESUMO

Nanoarray electrocatalysts with unique advantage of facilitating gas bubble detachment have garnered significant interest in gas evolution reactions (GERs). Existing research is largely based on a static hypothesis, assuming that buoyancy is the only driving force for the release of bubbles during GERs. However, this hypothesis overlooks the effect of the self-dynamic electrolyte flow, which is induced by the release of mature bubbles and helps destabilize and release the smaller, immature bubbles nearby. Herein, the enhancing effect of self-dynamic electrolyte flow on nanoarray structures is examined. Phase-field simulations demonstrate that the flow field of electrode with arrayed surface focuses shear force directly onto the gas bubble for efficient detachment, due to the flow could pass through voids and channels to bypass the shielding effect. The flow field therefore has a more substantial impact on the arrayed surface than the nanoscale smooth surface in terms of reducing the critical bubble size. To validate this, superaerophobic ferrous-nickel sulfide nanoarrays are fabricated and employed for water splitting, which display improved efficiency for GERs. This study contributes to understanding the influence of self-dynamic electrolyte on GERs and emphasizes that it should be considered when designing and evaluating nanoarray electrocatalysts.

11.
Chem Commun (Camb) ; 59(81): 12140-12143, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37740333

RESUMO

Placing blocking layers between electrodes has shown paramount prospects in suppressing the shuttle effect of Li-S batteries, but the associated ionic transport would be a concurrent obstacle. Herein, we present a Li-based crystal composited with carbon (LiPN2@C) by a one-step annealing of Li+ absorbed melamine polyphosphate, which simultaneously achieves alleviated polysulfide-shuttling and facilitated Li+ transport. As a homologous crystal, LiPN2 with abundant lithiophilic sites makes Li+ transport more efficient and sustainable. With a LiPN2@C-modified separator, the Li2S cathode exhibits a much-lower activation potential of 2.4 V and a high-rate capacity of 519 mA h g-1 at 2C. Impressively, the battery delivers a capacity of 726 mA h g-1 at 0.5C with a low decay rate of 0.25% per cycle during 100 continuous cycles.

12.
J Colloid Interface Sci ; 617: 391-398, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35279574

RESUMO

Surface Fe with low-coordination plays a decisive role in the performance of OER catalysts in basic media, however, it is still a huge challenge to construct a Fe-enriched surface. Herein, a novel S-incorporation and ligand anchoring strategy is reported for in-situ synthesis of surface-Fe enriched OER catalysts. During the OER test, the co-etching of S elements and ligands enables the formation of surface-Fe enriched trimetallic (oxy)hydroxide OER catalysts. Benefiting from the high catalytic activity of Fe enriched species on surface, the electrode delivers an ultralow overpotential of 234 mV to reach the current density of 10 mA cm-2 and a superior stability over 50 h. This efficient S-incorporation and ligand anchoring strategy offers a new perspective for in-situ construction of advanced earth-abundant OER catalysts.

13.
Adv Mater ; 34(37): e2204624, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35866182

RESUMO

Developing high-efficiency electrocatalysts for the hydrogen evolution and oxidation reactions (HER/HOR) in alkaline electrolytes is of critical importance for realizing renewable hydrogen technologies. Ruthenium phosphides (RuPx ) are promising candidates to substitute Pt-based electrodes; however, great challenges still remain in their electronic structure regulation for optimizing intermediate adsorption. Herein, it is reported that a homologous RuP@RuP2 core-shell architecture constructed by a phosphatization-controlled phase-transformation strategy enables strong electron coupling for optimal intermediate adsorption by virtue of the emergent interfacial functionality. Density functional theory calculations show that the RuP core and RuP2 shell present efficient electron transfer, leading to a close to thermoneutral hydrogen adsorption Gibbs free energy of 0.04 eV. Impressively, the resulting material exhibits superior HER/HOR activities in alkaline media, which outperform the benchmark Pt/C and are among the best reported bifunctional hydrogen electrocatalysts. The present work not only provides an efficient and cost-effective bifunctional hydrogen electrocatalyst, but also offers a new synthetic protocol to rationally synthesize homologous core-shell nanostructures for widespread applications.

14.
Front Mol Biosci ; 8: 674863, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055889

RESUMO

BACKGROUND: The coiled-coil domain containing (CCDC) family proteins have important biological functions in various diseases. However, the coiled-coil domain containing 137 (CCDC137) was rarely studied. We aim to investigate the role of CCDC137 in pan-cancer. METHODS: CCDC137 expression was evaluated in RNA sequence expression profilers of pan-cancer and normal tissues from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database. The influence of CCDC137 on the prognosis of tumor patients was analyzed using clinical survival data from TCGA. Function and pathway enrichment analysis was performed to explore the role of CCDC137 using the R package "clusterProfiler." We further analyzed the correlation of immune cell infiltration score of TCGA samples and CCDC137 expression using TIMER2 online database. RESULTS: CCDC137 was over-expressed and associated with worse survival status in various tumor types. CCDC137 expression was positively correlated with tumor associated macrophages (TAMs) and cancer associated fibroblasts (CAFs) in Lower Grade Glioma (LGG) and Uveal Melanoma (UVM). In addition, high CCDC137 expression was positively correlated with most immunosuppressive genes, including TGFB1, PD-L1, and IL10RB in LGG and UVM. CONCLUSIONS: Our study identified CCDC137 as an oncogene and predictor of worse survival in most tumor types. High CCDC137 may contribute to elevated infiltration of TAMs and CAFs and be associated with tumor immunosuppressive status.

15.
RSC Adv ; 9(53): 31177-31185, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35529388

RESUMO

In this study, novel Gd/TiO2@rGO (GTR) nanocomposites with high photocatalytic performance were fabricated via a one-pot solvothermal approach. During the preparation step, graphene oxide (GO) was reduced to reduced graphene oxide (rGO), and subsequently, on the surfaces of which anatase TiO2 doped with Gd metal was grown in situ with a 3D petal-like structure. Gd doping into the classical TiO2@rGO system efficiently expands the absorption range of light, improves the separation of photogenerated electrons, and increases the photocatalytic reaction sites. The specific surface areas, morphological structures, and valence and conduction bands of the obtained GTR nanocomposites were analyzed and correlated with their enhanced photocatalytic performances for the degradation of an aqueous RhB solution. The experimental results indicated that the best performance was achieved with the 3% GTR composite, which exhibited the highest photoelectrocatalytic activity because of two aspects: the rapid separation of electrons and holes, and improvement in adsorption capacity. As compared with pure TiO2, the GTR composites demonstrated enhanced photoactivity due to synergetic effects between the effective photo-induced electron transfer from TiO2 to the surface of the rGO acceptor through interfacial interactions and the variation of structure and electrons under the adoption of Gd.

16.
RSC Adv ; 8(52): 29645-29653, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35547273

RESUMO

We prepared a new three-dimensional, flower-like La-TiO2/g-C3N4 (LaTiCN) heterojunction photocatalyst using a solvothermal method. Analysis and characterization were performed by conducting scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform-infrared spectroscopy, ultraviolet-visible spectrophotometry, and nitrogen adsorption and desorption. The prepared g-C3N4 nanosheets could reach 100 nm in size and covered the TiO2 surface. A tightly bound interface formed between the g-C3N4 and TiO2, speeding up the effective transfer of photo-induced electrons. In addition, the incorporation of La3+ reduced the electron-hole recombination efficiency. Consequently, the prepared La-TiO2/g-C3N4 composite material exhibited better visible-light catalytic activity than pure TiO2.

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