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1.
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.

2.
Sensors (Basel) ; 23(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38067935

RESUMO

Three-dimensional (3D) porous graphene-based materials have displayed attractive electrochemical catalysis and sensing performances, benefiting from their high porosity, large surface area, and excellent electrical conductivity. In this work, a novel electrochemical sensor based on 3D porous reduced graphene (3DPrGO) and ion-imprinted polymer (IIP) was developed for trace cadmium ion (Cd(II)) detection in water. The 3DPrGO was synthesized in situ at a glassy carbon electrode (GCE) surface using a polystyrene (PS) colloidal crystal template and the electrodeposition method. Then, IIP film was further modified on the 3DPrGO by electropolymerization to make it suitable for detecting Cd(II). Attributable to the abundant nanopores and good electron transport of the 3DPrGO, as well as the specific recognition for Cd(II) of IIP, a sensitive determination of trace Cd(II) at PoPD-IIP/3DPrGO/GCE was achieved. The proposed sensor exhibited comprehensive linear Cd(II) responses ranging from 1 to 100 µg/L (R2 = 99.7%). The limit of detection (LOD) was 0.11 µg/L, about 30 times lower than the drinking water standard set by the World Health Organization (WHO). Moreover, PoPD-IIP/3DPrGO/GCE was applied for the detection of Cd(II) in actual water samples. The satisfying recoveries (97-99.6%) and relative standard deviations (RSD, 3.5-5.7%) make the proposed sensor a promising candidate for rapid and on-site water monitoring.

3.
J Am Chem Soc ; 143(3): 1553-1561, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33432813

RESUMO

Unprecedented interheteromacrocyclic hosts charge transfer (CT) crystals were generated by cooling organic solutions containing p-dimethoxybenzene-constituted pillar[5]arene (P5A) and p-benzoquinone-constituted pillar[5]quinone (P5Q). Despite the weak CT interaction known between p-dimethoxybenzene and p-benzoquinone and the lack of formation of CT complexes between P5A and P5Q in the solution phase, CT cocrystals between P5A and P5Q were formed with solvent molecules included into the hosts' cavities. Such a cocrystallization arises from an elegant synergy between the CT interaction and solvent-binding-promoted crystallization. The interhetero hosts CT crystals were studied by optical and electron microscopic techniques, X-ray powder diffraction, solid-state NMR, UV-vis, IR spectroscopic studies, and X-ray single-crystal studies. The solvent complexation was critical for formation of the supramolecular CT microcrystals. The CT absorption bands faded upon removing the solvent molecules under vacuum, but they could be recovered by reuptake of the solvent molecules. Intriguingly, the CT absorption bands and uptake kinetics are distinguishably different for various organic solvents, thus providing a unique way to distinguish between different commonly used chemicals.

4.
Cancer Cell Int ; 21(1): 550, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663343

RESUMO

BACKGROUND: Emerging studies have shown that long noncoding RNAs (lncRNAs) predominantly function in the carcinogenesis of multiple developing human tumors. The current study aimed to investigate the underlying mechanisms of LINC00337 in lung adenocarcinoma. METHODS: We analyzed TCGA and GTEx datasets and chose LINC00337 as the research object. Cell proliferation, cell apoptosis, cell cycle, migration, and invasion were detected in the gain and loss experiments of LINC00337 both in vitro and in vivo. Moreover, RNA pull-down, luciferase reporter assays, western blotting analysis, and rescue experiments were performed to investigate the underlying molecular mechanisms of LINC00337 function. RESULTS: LINC00337 expression was remarkably upregulated in lung adenocarcinoma. In addition, LINC00337 knockdown was shown to repress cell migration, invasion, and proliferation, as well as the cell cycle, and gear up apoptosis in lung adenocarcinoma in vitro and in vivo. With respect to the mechanism, LINC00337 knockdown boosted miR-1285-3p expression and then restrained YTHDF1 expression post-transcriptionally. Crucially, both miR-1285-3p decrement and YTHDF1 overexpression successfully reversed the influence on cell proliferation, migration, invasion, and apoptosis caused by LINC00337 shRNA. CONCLUSIONS: These results suggest that LINC00337 acts as an oncogenic lncRNA, targeting miR-1285-3p and regulating YTHDF1 expression, to promote the progression of lung adenocarcinoma.

5.
Sensors (Basel) ; 20(4)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069908

RESUMO

A novel electrochemical sensor based on electropolymerized ion imprinted poly (o-phenylenediamine) PoPD/electrochemical reduced graphene (ERGO) composite on glass carbon electrode (GCE) was fabricated for selective and sensitive determination of trace Cd(II) in water. ERGO was first deposited on the surface of GCE by electrochemical cyclic voltammetry (CV) scanning to enhance the electron transport activity at electrode surface. The ion imprinted polymer (IIP) of imprinted PoPD was then in situ electropolymerized on ERGO via CV scanning with oPD as functional monomer and Cd(II) ions as template, following removal of the template using electrochemical peroxidation method. The obtained imprinted PoPD/RERGO composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray energy spectroscopy (EDS) for the observation of their morphologies and components. The electrochemical behavior of the imprinted PoPD/ERGO/GCE was performed by CV and SWASV. The fabricated sensor of the imprinted PoPD/ERGO/GCE showed a good selectivity toward target Cd(II) ions in the presence of other heavy metal ions. Under the optimized experimental conditions, the sensor exhibited a good linear relationship between SWASV stripping peak values and Cd(II) concentration in the range of 1 to 50 ng/mL, with the limit of detection as 0.13 ng/mL (S/N = 3). The proposed electrochemical sensor of imprinted PoPD/ERGO/GCE was successfully applied for trace Cd(II) determination in real water samples.

6.
Sensors (Basel) ; 17(11)2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29125543

RESUMO

We have developed a novel mediated biochemical oxygen demand (BOD) biosensor based on immobilized Bacillus subtilis (B. subtilis) on three-dimensional (3D) porous graphene-polypyrrole (rGO-PPy) composite. The 3D porous rGO-PPy composite was prepared using hydrothermal method following with electropolymerization. Then the 3D porous rGO-PPy composite was used as a support for immobilizing negatively charged B. subtilis denoted as rGO-PPy-B through coordination and electrostatic interaction. Further, the prepared rGO-PPy-B was used as a microbial biofilm for establishing a mediated BOD biosensor with ferricyanide as an electronic acceptor. The indirect determination of BOD was performed by electrochemical measuring ferrocyanide generated from a reduced ferricyanide mediator using interdigited ultramicroelectrode array (IUDA) as the working electrode. The experimental results suggested a good linear relationship between the amperometric responses and BOD standard concentrations from 4 to 60 mg/L, with a limit detection of 1.8 mg/L (S/N ≥ 3). The electrochemical measurement of real water samples showed a good agreement with the conventional BOD5 method, and the good anti-interference as well as the long-term stability were well demonstrated, indicating that the proposed mediated BOD biosensor in this study holds a potential practical application of real water monitoring.


Assuntos
Técnicas Biossensoriais , Bacillus subtilis , Grafite , Polímeros , Pirróis
7.
Tumour Biol ; 37(9): 11825-11833, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27048285

RESUMO

This study aims to investigate CNE1 and CNE2 cell proliferation and apoptosis of nasopharyngeal cancer (NPC) and X-linked inhibitor of apoptosis protein (XIAP) expression in NPC patients after radiotherapy. Quantitative real-time quantitative polymerase chain reaction (qRT-PCR) and Western Blot detected XIAP and XIAP-associated factor1 (XAF1) messenger RNA (mRNA) and protein expression of CNE1 and CNE2 in NPC cells irradiated by γ-ray; MTT and flow cytometry assays detected CNE2 cells proliferation and apoptotic rate, respectively. With a retrospective analysis of 109 NPC patients in Xinxiang Central Hospital, immunohistochemistry (IHC) method detected XIAP expression, followed by a 5-year clinical analysis of the prognosis relevance after radiotherapy. In vitro, the inhibition and apoptotic rates of cells increased with the growth of radiation dose. qRT-PCR and Western blot detection declared that XIAP mRNA and protein expression increased, whereas XAF1 mRNA and protein expression decreased with the growth of radiation dose and exposure time. And XIAP mRNA and protein expression were negatively correlated with proliferation and apoptotic rates of the cells. In vivo, positive XIAP expression rate was negatively correlated with pathological tumor-node-metastasis (p-TNM) staging and tumor differentiation. Further, high XIAP expression, high p-TNM staging, and lower degree of differentiation were significantly correlated with the decrease of NPC patients' survival rate. Additionally, XIAP expression, p-TNM staging, and degrees of differentiation were independent risk factors for the survival of the NPC patients after radiotherapy. Increased XIAP expression and decreased XAF1 expression may be one reason for the apoptosis delays of CNE1 and CNE2 cells after irradiation, and the XIAP expression or the p-TNM staging and degree of differentiation are independent risk factors for NPC patients' survival after radiotherapy, providing a molecular rationale for radiotherapy and prognosis of NPC.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Proteínas de Neoplasias/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Adaptadoras de Transdução de Sinal , Apoptose/genética , Apoptose/efeitos da radiação , Proteínas Reguladoras de Apoptose , Western Blotting , Proliferação de Células/genética , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/metabolismo , Prognóstico , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
8.
J Phys Chem A ; 118(19): 3503-13, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24754754

RESUMO

The water-mediated neutral hydrolysis mechanism of carbonyl sulfide (OCS) has been re-examined using the hybrid supramolecule/continuum models with n = 2-8 explicit water cluster at the level of MP2(fc)(CPCM)/6-311++G(d,p)//MP2(fc)(CPCM)/6-31+G(d). Present calculations indicate that the potential energy surface in water solution is different from the one in the gas-phase, and only stepwise mechanism is observed in aqueous solution, i.e., monothiocarbonic acid (H2CO2S) is formed via monothiocarbonate (OCSOH(-), MTC) and its counterion, protonated water cluster, (H2O)nH3O(+). The predicted rate-determining step (RDS) barrier for the stepwise mechanism in water solution, about 90 kJ/mol, shows good agreement with the experimental values, 83.7-96.2 kJ/mol using six- or eight-water model including two cooperative water molecules. Moreover, two reaction pathways, the nucleophilic addition of water molecule across the C═O or the C═S bond of OCS are competitive.


Assuntos
Óxidos de Enxofre/química , Água/química , Hidrólise , Estrutura Molecular , Teoria Quântica
9.
Anal Methods ; 16(2): 179-188, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047435

RESUMO

A novel multi-functional microfluidic paper-based analytical device (µPAD) integrated with ion imprinted polymers (IIPs) was proposed for specific, portable and low-cost detection of cadmium (Cd(II)) in water. The IIP was grafted on paper and integrated into the µPAD for separation of Cd(II) through multi-layer design. The paper-based screen printed carbon electrode (pSPCE) modified with reduced graphene oxide was fabricated and combined with the µPAD for electrochemical sensing of the separated Cd(II). Reduced graphene oxide (rGO) was prepared via electroreduction on the working electrode surface of the pSPCE (rGO/pSPCE), which provided a sensitization effect with an improved signal for Cd(II) detection. The µPAD developed with the integrated IIP and combined with rGO/pSPCE is able to detect Cd(II) with a linear range from 1 ng ml-1 to 100 ng ml-1 and a detection limit of 0.05 ng ml-1. The accuracy of this µPAD was evaluated with spiked real water samples and compared with that of the inductively coupled plasma mass spectrometry (ICP-MS) method, from which the recovery values ranged from 96.5% to 114.2% with RSDs <10% between the two methods. This µPAD demonstrated its advantages of low-cost, portability, and suitability for highly sensitive detection of Cd(II), making it a valuable tool for on-site analysis.

10.
Biomimetics (Basel) ; 8(2)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37366851

RESUMO

In response to the requirements of large-scale space in-orbit assembly and the special environment of low gravity in space, this paper proposes a small robot structure with the integration of assembly, connection, and vibration reduction functionalities. Each robot consists of a body and three composite mechanical arms-legs, which can dock and transfer assembly units with the transport spacecraft unit, and also crawl along the edge truss of the assembly unit to a designated location to complete in-orbit assembly while ensuring precision. A theoretical model of robot motion was established for simulation studies, and in the research process, the vibration of the assembly unit was studied, and preliminary adjustments were made to address the vibration issue. The results show that this structure is feasible for in-orbit assembly schemes and has good adjustment ability for flexible vibration.

11.
Biosens Bioelectron ; 211: 114341, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594625

RESUMO

In this paper, we describe a simple and practical way to prepare hydrogel membranes in a conical channel (pipette tip). We used a pipette to create a gas pressure difference on both sides of the gel precursor, which drove the gel precursor to move in the pipette tip. During movement, the shape of the hydrogel precursor gradually becomes thinner as the radius of the tapered channel becomes larger. We use this principle to realize the highly controllable preparation of the hydrogel membrane structure (130 µm at its thinnest). Moreover, we fabricated a hydrogel membrane sensor in one step by implanting smart molecules in the hydrogel, which achieved rapid and sensitive detection of 0.5 µM-500 mM potassium ions. This method of preparing the hydrogel membrane sensor does not rely on professional membrane production equipment and complex molecular design processes, has high gel utilization and simple and controllable membrane thickness, and has a wide range of application value in the field of intelligent hydrogel-based analysis technology.


Assuntos
Técnicas Biossensoriais , Hidrogéis/química , Íons , Pressão
12.
Org Lett ; 24(1): 38-42, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-34932357

RESUMO

A highly enantioselective γ-addition-driven cascade of ß,γ-unsaturated carbonyl compounds by bifunctional ion-pair catalysis has been developed. With this protocol, a range of functionalized chiral 1,3-dioxolochroman derivatives were prepared in high yields with superior stereoselectivities (>99% ee and >20:1 dr). The utility of this method was demonstrated by one-pot synthesis, scaled-up preparation, and facile transformation. Moreover, mechanistic investigations provided insights into the reaction pathway and the origin of chiral induction.

13.
Lab Chip ; 21(4): 719-724, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33475116

RESUMO

Distance-based detection methods with a quantitative readout are of great significance to point-of-care testing (POCT), are low-cost and user-friendly, and can be integrated into portable analytical devices. Here, we submit a visual quantitative distance-based sensor by capillary force alteration in a capillary tube. This sensor converts the wettability alteration caused by the target molecules into a capillary rise height signal. Moreover, the sensor profits from isothermal amplification technology, achieving the detection of miRNAs with high sensitivity and specificity by visually reading the height of the water in the capillary tube. The proposed biosensor shows great potential in routine clinical diagnosis as well as POCT in resource-limited settings.


Assuntos
Técnicas Biossensoriais , Testes Imediatos , Molhabilidade
14.
Chem Commun (Camb) ; 57(14): 1806-1809, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33476351

RESUMO

A supramolecular strategy for detecting the concentration of polyamines has been established through competitive/synergetic complexation among polyamines, CB[7], γ-CD, and pyrene derivatives, which allows for convenient, rapid, and high throughput spectral/visual detection of the concentration of urinary polyamines based on the switching on/off of the pyrene excimer fluorescence.

15.
Neurosci Res ; 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33940081

RESUMO

Long non-coding RNAs (lncRNAs) have been reported to biologically regulate tumor progression. LncRNA MIR31HG has been identified as an oncogene in several cancer types, but its role and mechanism in glioblastoma (GBM) remain to be explored. In the present study, we detected strongly-expressed MIR31HG in GBM cells through RT-qPCR analysis. Through loss-of-function assays, we uncovered that MIR31HG exerted its oncogenic property in GBM through boosting cell proliferation and suppressing the apoptosis. Mechanistically, STAT1 was found to be as a transcription factor and played a part in activating the transcription of MIR31HG with upregulating the expression of MIR31HG in GBM. Moreover, high MIR31HG level was confirmed to induce the activation of Wnt/ß-catenin signaling pathway in a variety of cancers. From subcellular fractionation and western blot assays, it was displayed that MIR31HG activated Wnt/ß-catenin signaling pathway through enhancing the nuclear translocation of ß-catenin. Rescue assays showed that the treatment of LiCl countervailed MIR31HG depletion-induced inhibition on GBM cell growth. In conclusion, STAT1-induced upregulation of lncRNA MIR31HG facilitates GBM cell growth by activating Wnt/ß-catenin signaling pathway.

16.
ACS Appl Mater Interfaces ; 13(42): 50258-50269, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637260

RESUMO

Lithium-sulfur (Li-S) batteries have been widely considered as the next-generation energy storage system but hindered by the soluble polysulfide intermediate-induced shuttle effect. Doping heteroatoms was confirmed to enhance the affinity of polysulfide and the carbon host, release the shuttle effect, and improve the battery performance. To enhance the Lewis acidity and reinforce the interaction between polysulfide and the carbon skeleton, a novel covalent triazine framework (CTFO) was designed and fabricated by copolymerizing 2,4,6-triphenoxy-s-triazine and 2,4,6-trichloro-1,3,5-triazine through Friedel-Crafts alkylation. Polymerization led to triazine substitution on the para-position of the phenoxy groups of 2,4,6-triphenoxy-triazine and produced two-dimensional three-connected honeycomb nanosheets. These nanosheets were confirmed to exhibit packing in the AB style through the intralayer π-π interaction to form a three-dimensional layered network with micropores of 0.5 nm. The practical and simulated results manifested the enhanced polysulfide capture capability due to the abundant N and O heteroatoms in CTFO. The unique porous polar network endowed CTFO with improved Li-S battery performance with high Coulombic efficiency, rate capability, and cycling stability. The S@CTFO cathode delivered an initial discharge capacity of 791 mAh g-1 at 1C and retained a residual capacity of 512 mAh g-1 after 300 charge-discharge cycles with an attenuation rate of 0.117%. The present results confirmed that multiple heteroatom doping enhances the interaction between the porous polar CTF skeleton and polysulfide intermediates to improve the Li-S battery performance.

17.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): o645, 2010 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21580399

RESUMO

In the title compound, C(18)H(19)NO(2), the five-membered ring of the indane fragment adopts an envelope conformation with the unsubstituted carbon atom at the flap displaced by 0.412 (3) Šfrom the plane formed by the other four atoms. The nitro group forms a dihedral angle of 5.3 (2)° with the indane benzene ring while the dihedral angle between the phenyl ring and the indane benzene ring is 76.74 (9)°.

18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o212, 2009 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-21581832

RESUMO

The asymmetric unit of the title compound, C(22)H(22)O(4)S·2H(2)O, contains one quarter of the organic mol-ecule and one half water mol-ecule, the site symmetries of the S atom and the water O atom being mm2 and m, respectively. The dihedral angle between the benzene rings is 76.27 (11)°. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into chains running parallel to the a axis.

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): o794, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-21582518

RESUMO

In the mol-ecule of the title compound, C(21)H(18)O(9), the two aromatic rings are aligned at an angle of 49.7 (1)°.

20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1823, 2009 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21583525

RESUMO

In the mol-ecule of the title compound, C(25)H(20)N(2)O(3), the dihedral angles formed by adjacent benzene rings are 66.75 (8), 48.37 (8) and 71.43 (9)°. In the crystal structure, centrosymmetrically related mol-ecules are linked into dimers by inter-molecular N-H⋯O hydrogen bonds.

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