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2D mesoporous materials fabricated via the assembly of nanoparticles (NPs) not only possess the unique properties of nanoscale building blocks but also manifest additional collective properties due to the interactions between NPs. In this work, reported is a facile and designable way to prepare free-standing 2D mesoporous gold (Au) superstructures with a honeycomb-like configuration. During the fabrication process, Au NPs with an average diameter of 5.0 nm are assembled into a superlattice film on a diethylene glycol substrate. Then, a subsequent thermal treatment at 180 °C induces NP attachment, forming the honeycomb-like ordered mesoporous Au superstructures. Each individual NP connects with three neighboring NPs in the adjacent layer to form a tetrahedron-based framework. Mesopores confined in the superstructure have a uniform size of 3.5 nm and are arranged in an ordered hexagonal array. The metallic bonding between Au NPs increases the structural stability of architected superstructures, allowing them to be easily transferred to various substrates. In addition, electron energy-loss spectroscopy experiments and 3D finite-difference time-domain simulations reveal that electric field enhancement occurs at the confined mesopores when the superstructures are excited by light, showing their potential in nano-plasmonic applications.
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The hierarchical CuCo2O4@carbon quantum dots (CQDs) hollow microspheres constructed by 1D porous nanowires have been successfully prepared through a simple CQDs-induced hydrothermal self-assembly technique. XPS analysis shows the CuCo2O4@CQDs possesses the Co(II)-rich surface associated with the oxygen vacancies, which can effectively boost the Faradaic reactions and oxygen evolution reaction (OER) activity. For example, the as-synthesized 3D porous CuCo2O4@CQDs electrode exhibits high activity toward overall electrochemical water splitting, for example, an overpotential of 290 mV for OER and 331 mV for hydrogen evolution reaction (HER) in alkaline media have been achieved at 10 mA cm-2, respectively. Furthermore, an asymmetric supercapacitor (ASC) (CuCo2O4@CQDs//CNTs) delivers a high energy density of 45.9 Wh kg-1 at 763.4 W kg-1, as well as good cycling ability. The synergy of Co(II)-rich surface, oxygen vacancies, and well-defined 3D hollow structures facilitates the subsequent surface electrochemical reactions. This work presents a facile method to fabricate energetic nanocomposites with highly reactive, durable, and universal functionalities.
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We report a facile method to realize the selective synthesis of Cs xPb yBr z-based perovskites, including CsPbBr3, Cs4PbBr6 and CsPb2Br5. The use of an appropriate amount of N, N-dimethylformamide (DMF) solvent is experimentally determined to play a critical role in the controlled formation of various perovskite products. With continuously increasing DMF concentration, first CsPbBr3 nanocrystals with tunable size can be achieved, and then the production of Cs4PbBr6 and CsPb2Br5 perovskite analogues is successively realized. Our findings present a novel path for the controlled synthesis of other perovskite analogues for specific applications.
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BACKGROUND: Interleukin-27 (IL-27) has been recognized as a pleiotropic cytokine with both pro- and anti-inflammatory properties. PATIENTS AND METHODS: A case-control study was conducted to investigate the possible associations of IL-27 gene polymorphisms with susceptibility to cervical cancer and clinical outcome. RESULTS: Our results suggested that the IL-27 2905T/G was significantly associated with a decreased risk of cervical cancer. Further analysis showed IL-27 2905T/G genotypes were associated with advanced tumor stages of cervical cancer patients. More interestingly, the IL-27 2905T/G genotypes were statistically significantly associated with the survival in cervical cancer patients. CONCLUSION: Our results showed that the IL-27 2905T/G genotypes were associated with decreased the susceptibility and development of cervical cancer in Chinese Han population.
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Estudos de Associação Genética , Predisposição Genética para Doença , Interleucinas/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Alelos , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Neoplasias do Colo do Útero/patologiaRESUMO
AIM: Breast cancer 2, early onset (BRCA2) has been reported to be associated with familial breast and ovarian cancer. Several proteins interact with conserved regions of BRCA2, which play significant roles in DNA damage repair and centrosomal localization. This study was aimed to identify a novel protein, Wilms tumor 1 interacting protein (WTIP), which might interact with the conserved regions of BRCA2, as well as the functional role of silencing of WTIP in response to centrosomal localization. MATERIALS AND METHODS: Hela S3 cells were used in our study. A yeast two-hybrid screening was used to identify a novel BRCA2-interacting protein. Coimmunoprecipitation and glutathione S-transferase (GST) pull-down assays were performed to detect protein-protein interaction between BRCA2 and hemaglutinin (HA)-WTIP. The expression of WTIP was silenced by short hairpin RNA (shRNA) and the levels of WTIP were confirmed by Western blot. Immunofluorescence microscopy was performed to study the centrosome localization. The functional role of knocking down WTIP expression in response to centrosomal localization was then investigated. RESULTS: The results showed that there was an interaction between WTIP and BRCA2 (amino acids 2750-2864) in Hela S3 cells. We found that WTIP interacted with BRCA2 in both exogenous and endogenous level. The expression levels of WTIP were significantly decreased by siRNA compared to the control group. Downregulation of WTIP abolished BRCA2 centrosome localization and abnormal cell division. CONCLUSION: This study indicates that WTIP interacts with BRCA2 and might be responsible for BRCA2 centrosome localization in cervical cancer cell.
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Proteína BRCA2/fisiologia , Proteínas de Transporte/fisiologia , Centrossomo/metabolismo , Neoplasias do Colo do Útero/metabolismo , Proteína BRCA2/análise , Proteínas Correpressoras , Proteínas do Citoesqueleto , Feminino , Células HeLa , Humanos , RNA Interferente Pequeno/genéticaRESUMO
Genetic polymorphisms in the Fas/Fas ligand (FasL) gene were proposed to be associated with susceptibility to cervical cancer, but previous studies reported controversial findings. We performed a meta-analysis to assess the associations between Fas/FasL polymorphisms and susceptibility to cervical cancer. We carried out a literature search in PubMed and Embase databases for studies on the associations between Fas/FasL polymorphisms and susceptibility to cervical cancer. The associations were assessed by odds ratio (OR) together with its 95% confidence intervals (CIs). Eleven individual studies with a total of 6,919 subjects were finally included into the meta-analysis. Overall, there was no association between Fas 1377G > A polymorphism and susceptibility to cervical cancer (A vs. G: OR = 0.99, 95% CI 0.88-1.12, P = 0.91; AA vs. GG: OR = 1.00, 95% CI 0.76-1.32, P = 0.99; AA/GA vs. GG: OR = 0.95, 95% CI 0.81-1.12, P = 0.54; AA vs. GG/GA: OR = 1.11, 95% CI 0.85-1.43, P = 0.45). In addition, there was also no association between FasL 844 T > C polymorphism and susceptibility to cervical cancer (C vs. T: OR = 1.12, 95% CI 0.91-1.36, P = 0.28; CC vs. TT: OR = 1.17, 95% CI 0.90-1.51, P = 0.24; CC/TC vs. TT: OR = 1.13, 95% CI 0.92-1.39, P = 0.24; CC vs. TT/TC: OR = 1.11, 95% CI 0.83-1.50, P = 0.47). In subgroup analysis by ethnicity, there were also no associations between Fas/FasL polymorphisms and susceptibility to cervical cancer in Asians and Africans. In conclusion, Fas 1377G > A polymorphism and FasL 844 T > C polymorphism are both not associated with susceptibility to cervical cancer.
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Proteína Ligante Fas/genética , Predisposição Genética para Doença , Polimorfismo Genético , Neoplasias do Colo do Útero/genética , Receptor fas/genética , Feminino , Humanos , Risco , Neoplasias do Colo do Útero/etiologiaRESUMO
Tin phosphide has gained extensive attention as a prospective anode for lithium/potassium ion batteries because of its high theoretical capacity. Nevertheless, the fast capacity fading, which is induced by the huge volume expansion and poor electrical conductivity during cycling, severely restricts its practical applications. In this work, a SnP3-CNTs/KB composite with a SnP3 content as high as 90 wt% was successfully synthesized by a two-step ball milling method. SnP3 nanoparticles were tightly encapsulated in multi-geometric composite carbon layers to efficiently relieve the volume changes and enhance conductivity. Specifically, the resulting SnP3-CNTs/KB anode showed a specific capacity up to 998.6 mA h g-1 after 100 cycles at 50 mA g-1 and 810.4 mA h g-1 after 500 cycles at 1000 mA g-1 for lithium ion batteries. For potassium ion batteries, a high reversible capacity of 200.2 mA h g-1 was achieved after 200 cycles at 1000 mA g-1. This work affords a new insight for exploring excellent support structures of tin phosphide-based anodes.
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The production of hydrogen through seawater electrolysis has recently garnered increasing concern. However, hydrogen evolution reaction (HER) by alkaline seawater electrocatalysis is severely impeded by the slow H2O adsorption and H* binding kinetics at industrial current densities. Herein, a face-centered cubic/hexagonal close packed (fcc/hcp) NiRu alloy heterojunction was fabricated on Ni foam (N doped NiRu-inf/NF) by a low-temperature nitrogen plasma activation. Simultaneously, nitrogen atoms are introduced into the alloy to facilitate d-p hybridization. When N doped NiRu-inf/NF is integrated into a dual-electrode cell for urea-assisted seawater electrolysis, it achieves 100 mA cm-2 with an ultra-low voltage of 1.36 V and excellent stability. Density functional theory (DFT) verifies that the robust d-p hybridization among Ni, Ru and N exhibits more energy level matching for H2O molecule adsorption at the Ru sites, while simultaneously reducing the interaction between H* and Ni sites in N-doped NiRu-inf.
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The previous research addressed the waste problem of agriculture and forestry residues by exploring the efficient utilization of liquefied soybean straw in supercapacitor. The structures of the liquefied soybean straw were controlled by coupling microwave hydrothermal treatment with carbonization under the influence of a C3N4 bifunctional template. What's more, C3N4 could effectively regulate the pore structures and provide an effective N active site of carbon materials C3N4. The obtained N-SLR Carbon-700 possess a specific surface area of up to 1593.7â m2 g -1, and the pore size is mainly concentrated in the range of 1.8-2.5â nm, providing efficient ions transmission channels and storage space. Its specific capacitance is up to 261.5â F g-1 (current density of 0.5â A g-1), and the capacity retention is 74.04 % when the current density is expanded by 20 times. In the two-electrode system, the energy density of N-SLR Carbon-700 could reach to 31.3â W h kg-1 at a power density of 360â W kg-1, as well as the energy surface density is maintained at 69 % when the power density is increased by a factor of 20. This work enhances effectively the charging and discharging stability and capacitance value of carbon-based supercapacitor.
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Accumulating evidence has supported the concept that long noncoding RNAs (lncRNAs) participate in the initiation and progression of human cervical cancer (CC). The long intergenic nonprotein-coding RNA 173 (LINC00173) is a recently identified cancer-associated factor. However, the expression and biological role of LINC00173 in CC are poorly understood. Here, for the first time, we found that the expression of LINC00173 was decreased in CC tissues compared with that in nontumor tissues. Data from The Cancer Genome Atlas (TCGA) further revealed that the downregulated expression of LINC00173 in CC tissues was correlated with poor survival. Functionally, LINC00173 overexpression suppressed HeLa cell proliferation via induction of G0/G1 phase arrest. Ectopic expression of LINC00173 also repressed the invasiveness of HeLa cells. Conversely, LINC00173 depletion resulted in the enhanced proliferation and invasiveness of C33A cells. Mechanistically, LINC00173 functioned as a molecular sponge for miR-182-5p and inversely regulated the miR-182-5p level in CC cells. F-box and WD repeat domain-containing 7 (FBXW7) was identified as the target of miR-182-5p. LINC00173 overexpression enhanced the FBXW7 level via regulation of miR-182-5p in HeLa Cells. More importantly, the inhibitory effects of LINC00173 on HeLa cell proliferation and invasiveness were reversed by FBXW7 silencing. Taken together, the results indicate that the LINC00173/miR-182-5p/FBXW7 axis is critical for CC progression, which might offer new insights into effective therapy for CC.
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Proteína 7 com Repetições F-Box-WD/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Biomarcadores Tumorais/genética , Proliferação de Células/genética , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HeLa , Humanos , Invasividade Neoplásica/genética , Transdução de Sinais/genéticaRESUMO
Engineering novel Sn-based bimetallic materials could provide intriguing catalytic properties to boost the electrochemical CO2 reduction. Herein, the first synthesis of homogeneous Sn1- x Bix alloy nanoparticles (x up to 0.20) with native Bi-doped amorphous SnOx shells for efficient CO2 reduction is reported. The Bi-SnOx nanoshells boost the production of formate with high Faradaic efficiencies (>90%) over a wide potential window (-0.67 to -0.92 V vs RHE) with low overpotentials, outperforming current tin oxide catalysts. The state-of-the-art Bi-SnOx nanoshells derived from Sn0.80 Bi0.20 alloy nanoparticles exhibit a great partial current density of 74.6 mA cm-2 and high Faradaic efficiency of 95.8%. The detailed electrocatalytic analyses and corresponding density functional theory calculations simultaneously reveal that the incorporation of Bi atoms into Sn species facilitates formate production by suppressing the formation of H2 and CO.
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Tin-based nanomaterials have been of increasing interest in many fields such as alkali-ion batteries, gas sensing, thermoelectric devices, and solar cells. Finely controllable structures and compositions of tin-based nanomaterials are crucial to improve their performances. The solution-based colloidal synthesis of these compounds offers a promising path toward controlling their structures and components. This feature article summarizes the progress in recent studies on the colloidal synthesis of tin-based nanomaterials (such as metallic tin, alloys, oxides, chalcogenides, and phosphides) and their applications in alkali-ion batteries including our own recent contributions to this subject. The challenges and future outlook of the controllable synthesis and practical development of tin-based anode materials are also addressed.
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Intractable hurdles of low Coulombic efficiency and dendritic Li formation during a repeated deposition/stripping process hinder the commercial use of Li metal anode for next-generation battery systems. Achieving uniform Li nucleation is one of the effective strategies to address these issues, and it is of practical importance to realize this on a commercial Cu current collector that is lithiophobic. Herein, we design a nanostructured Ag lithiophilic layer on a Cu foil via an electroless plating process for a Li metal current collector. The deposition of lithiophilic Ag particles that are homogeneously distributed on the Cu foil can reduce the nucleation overpotential, realizing uniform Li nucleation and subsequently flat Li plating. As a result, a stable cycle stability of up to 360 h (1 mA cm-2) and an average Columbic efficiency of 94.5% for 100 cycles (1 mA cm-2) are achieved. Furthermore, CuAg full cells with LiFePO4 as a cathode exhibit good cycle performances and low polarization voltage. This approach provides another facile way for a stable lithium metal anode.
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Na metal is a promising anode for Na batteries owing to its high theoretical capacity and low reduction potential. Nevertheless, an unstable and inhomogeneous solid electrolyte interphase originated from the instantaneous reactions between the Na metal anode and organic liquid electrolyte causes the intractable hurdles of dendrite growth and low Coulombic efficiency. Here, a sodium fluoride (NaF)-poly(vinylidene difluoride) (PVDF) inorganic-organic hybrid protective layer is constructed on a commercial Cu current collector via a simple blade-coating technique. A flexible PVDF matrix can endure volume change, maintaining the integrity of the anode/coating interface, while NaF particles provide improved Na+ diffusion conductivity and mechanical strength, suppressing the dendrite initiation and growth. Based on these synergetic effects, an excellent cycle life of more than â¼2100 h is realized at 1 mA cm-2 at 50% depth of discharge (DOD), which outperforms 10-fold lifetime of the Cu current collector (â¼170 h). Moreover, the Cu current collector with a NaF-PVDF protective layer also delivers good cycling stability at 5 mA cm-2 and an ultrahigh DOD (80%). The rational design of the hybrid protective layer offers a new approach to realize stable Na metal batteries.
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Ultrathin metal-organic framework (MOF) nanosheets possessing inherent advantages of both two-dimensional (2D) features and MOFs are attracting intensive research interest. The direct manufacture of MOF nanosheets is still a challenge up to now. Here, we have developed a novel bottom-up approach to synthesize zeolitic imidazolate framework-67 (ZIF-67) nanosheets, which can be in situ converted into Co3O4 ultrathin nanomeshes after thermal treatment. Interestingly, the obtained Co3O4 nanomeshes are rich in oxygen defects, providing fruitful active sites for the faradaic reaction. The modified electrode exhibits a large specific capacitance (1216.4 F g-1 at 1 A g-1), as well as a high rate capability (925.5 F g-1 at 20 A g-1). Moreover, an asymmetric supercapacitor made of Co3O4//activated carbon shows an energy density of 46.5 Wh kg-1 at 790.7 W kg-1. Furthermore, the 2D Co3O4 ultrathin nanomeshes show an outstanding performance for the oxygen evolution reaction with an overpotential of 230 mV at the onset potential and a small Tafel slope of 74.0 mV dec-1. The present method presents a facile avenue to the preparation of other 2D ultrathin metal oxide nanostructures with various applications in energy catalysis and conversion.
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Colloidal nanocrystals (NCs) of metal halide perovskite have recently aroused great research interest, due to their remarkable optical and electronic properties. We report a solution synthesis of a new member in this category, that is, all-inorganic lead-free cesium germanium iodine (CsGeI3 ) perovskite NCs. These CsGeI3 colloidal NCs are confirmed to adopt a rhombohedral structure. Moreover, the electron beam-induced transformations of these lead-free perovskite NCs have been investigated for the first time. The fracture of single-crystalline CsGeI3 nanocubes occurs first, followed by the emergence and growth of cesium iodine (CsI) single crystals and the final fragmentation into small debris with random orientations. Notably, the electron-reduced Ge species in CsGeI3 nanocubes exhibit a distinctive transformation path, compared to heavier Pb atoms in lead halide perovskite NCs.
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Well-defined PtNi nanocrystals represent one of the most efficient electrocatalysts to boost the oxygen reduction reaction (ORR), especially in the shape of octahedrons, nanoframes, and nanowires. However, the synthesis of complex PtNi nanostructure is still a great challenge. Herein, we report a new class of PtNi hexapods with high activity and stability toward ORR. The hexapods are prepared by selective capping and simultaneous corrosion. By controlling the oxidative etching, PtNi polyhedrons and nanoparticles are obtained, respectively. The intriguing hexapods are composed of six nanopods with an average length of 12.5 nm. Due to their sharp tips and three-dimensional (3D) accessible surfaces, the PtNi hexapods show a high mass activity of 0.85 A mg Pt - 1 at 0.9 V vs. RHE, which are 5.4-fold higher than commercial Pt/C, also outperforming PtNi polyhedrons and PtNi nanoparticles. In addition, the mass activity of PtNi hexapods maintains 92.3% even after 10,000 potential cycles.
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We report a mild synthetic method to access Sn nanocrystals with tunable diameter and narrow size distribution (6-8%). The self-templated formation of various types of Sn chalcogenide hollow nanostructures including oxides, sulfides, selenides, and tellurides is also demonstrated for the first time. The use of air-stable tungsten hexacarbonyl that produces carbon monoxide at elevated temperature to reduce the SnCl2 precursor and coordinate the nanoparticle surface is thought to play an essential role in this method. This synthesis method is likely to be extended to other metal systems and could find potential applications including battery anodes and catalysts.
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Calcitriol (1α,25-dihydroxyvitamin D3) has demonstrated anticancer activity against several tumors. However, the underlying mechanism for this activity is not yet fully understood. Our experiment was designed and performed to address one aspect of this issue in cervical cancer. HeLa S3 cells were cultured in media with various concentrations of calcitriol. Cell proliferation and cell cycle were assessed by spectrophotometry and flow cytometry, respectively. The mRNA and protein expression levels of human cervical cancer oncogene (HCCR-1) and p21 were determined by RT-PCR and Western blot, respectively. Results indicated that calcitriol inhibited HeLa S3 cell proliferation and induced cell cycle arrest at the G1 phase. Calcitriol decreased HCCR-1 protein expression in a dose- and time-dependent manner. Furthermore, promoter activity analyses revealed that transcriptional regulation was involved in the inhibition of HCCR-1 expression. Overexpression of HCCR-1 in HeLa S3 cells reversed the inhibition of cell proliferation and G1 phase arrest that resulted from calcitriol treatment. In addition, calcitriol increased p21 expression and promoter activity. HCCR-1 overexpression decreased p21 expression and promoter activity. Thus, our results suggested that calcitriol inhibited HeLa S3 cell proliferation by decreasing HCCR-1 expression and increasing p21 expression.