Materials
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2020
·Vol. 13
·期 3
·755
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IF 3.057
Lingfei Li,Qiu Sun,Xiangqun Chen,Yongjun Xu,Zhaohua Jiang
In this work, poly(1-butene) (PB-1) composite films with multi-walled carbon nanotubes (MWCNT) were prepared by a solution casting method. The relationship between the dielectric properties and the crystal transformation process of the films was investigated. It was indicated that there were two crystal forms of I and II of PB-1 during the solution crystallization process. With the prolongation of the phase transition time, form II was converted into form I. The addition of the conductive filler (MWCNT) accelerated the rate of phase transformation and changed the nucleation mode of PB-1. The presence of crystal form I in the system increased the breakdown strength and the dielectric constant of the films and reduced the dielectric loss, with better stability. In addition, the dielectric constant and the dielectric loss of the MWCNT/PB-1 composite films increased with the addition of MWCNT, due to the interfacial polarization between MWCNT and PB-1 matrix. When the mass fraction of the MWCNT was 1.0%, the composite film had a dielectric constant of 43.9 at 25 °C and 103Hz, which was 20 times that of the original film.Keywords:poly(1-butene);multi-walled carbon nanotubes;solution crystallization;dielectric properties;breakdown strength
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MICROCHEMICAL JOURNAL
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2020
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IF 3.594
Lulu Hao,Liying Zhao,Guangbao Li,Yingying Li,Ligang Ma,Yanju Liu,Wenbin Wang,Jinming Kong
Cytokeratin fragment antigen 21-1 (CYFRA 21-1) DNA is a significant biomarker with relation to non-small cell lung cancer. Here, we described an ultrasensitive electrochemical biosensor for detection of CYFRA 21-1 DNA (target DNA, tDNA) via surface-initiated reversible addition fragmentation chain transfer (SI-RAFT) polymerization-based DNA metallization signal amplification strategy. Specifically, 5′terminal modified thiol peptide nucleic acid (PNA) probes are immobilized on the gold electrode surface (by Au-S selfassembly) for the identification of specific tDNA sequences. After hybridization, the 4-cyano-4-(phenylcarbonothioylthio) pentanoic acid (CPAD) is tethered to the PNA/DNA duplexes by means of the recognized phosphate-Zr 4+ -carboxylate chemistry. Subsequently, in the situation of C 3 H 4 O as the monomer, SI-RAFT polymerization can bring numerous aldehyde groups sites for the subsequent silver mirror reaction. The acrolein-polymers act as reductant to reduce Ag + into Ag 0 , and then the silver particles are deposited on the polymer skeleton, which significantly amplifies the electrochemical signal. Under optimal conditions, the designed sensor for tDNA detection show a wide linear range from 100 aM to 1 nM, and the detection limit is as low as 0.89 aM. Moreover, the proposed biosensor exhibits prominent applicability for analysis of tDNA in serum samples and high selectivity for different mismatched oligonucleotide fragments. Given the proposed biosensor without extra natural enzyme or bio-labels, this method has enormous potential in bioanalysis.
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SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Jiuli Han,Lu Bai,Shuangjiang Luo,Bingbing Yang,Yinge Bai,Shaojuan Zeng,Xiangping Zhang
Ionic liquids (ILs) are attractive and prospective materials used in membranes due to the nonvolatility, structure tunability, and the ability to tune the interface compatibility. The cobalt IL Bmim 2 Co(NCS) 4 possesses the porphyrin-like N4-coordinated cobalt center which could selectively and reversibly interact with O 2 . Herein the Bmim 2 Co(NCS) 4 as liquid-phase oxygen carrier was used to fabricate thin-film composite (TFC) membrane with the polymer of intrinsic microporosity (PIM-1). The microstructures, properties and gas separation performance of the membrane were compared with the TFC membrane which takes cobalt porphyrin (T(4-Cl)PPCo) as a carrier. We found that the addition of a small amount of T(4-Cl)PPCo can enlarge the d -spacing of packed chains of PIM-1 and significantly increase the fractional free volume (FFV) and the gas permeability of the membrane, but the selectivity is unsatisfactory. It is worth noting that adding Bmim 2 Co(NCS) 4 into the polymer can increase greatly the O 2 /N 2 selectivity which is higher than that of the membrane with T(4-Cl)PPCo. Although the addition of Bmim 2 Co(NCS) 4 decreases the d -spacing of packed chains of PIM-1, resulting in the slight decline of FFV and gas permeability of the membrane, the Bmim 2 Co(NCS) 4 /PIM-1 TFC membranes exhibit better O 2 /N 2 separation performance than the T(4-Cl)PPCo/PIM-1 TFC membranes in consideration of the Robeson upper bound.
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RSC Advances
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2020
·Vol. 10
·期 17
·10006-10016
·
IF 3.119
Ruimin Li,Shiyong Xing,Shuai Zhang,Minghan Han
H-beta zeolites of 100–200 nm (named BEA-L) and 20–30 nm (named BEA-S) were treated by chemical liquid deposition (CLD) of tetraethyl orthosilicate (TEOS) to improve the selectivity of 2-phenyl linear alkylbenzene (2-LAB) from benzene alkylation with 1-dodecene. The results indicate that H-beta zeolite with a smaller crystal size has a longer lifetime due to shorter channels and less diffusion limitation. The deposited SiO2 layers passivated the external surface acid sites of the zeolite and made the pores narrower. BEA-L lost more external Brønsted acid sites than BEA-S with the same added amount of TEOS, which was due to the severe aggregation of BEA-S grains. This increased passivation gave BEA-L increased 2-LAB selectivity. And when the added amount of SiO2 was 7.20 wt% of the parent zeolite, the selectivity of 2-LAB over BEA-L significantly increased from 41.9% to 54.7% while that of BEA-S only increased by 2%.
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CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Ihtisham Ul Haq,Shen Hui Li,Hong-Gang Zhen,Rehan Khan,Ao-Shuai Zhang,Zhi-Ping Zhao
For separating 1, 3-butadiene (BD) from BD/N 2 mixture, among numerous studied metal–organic frameworks-based adsorbents, Ni-ZIF-8 was comparatively selected here based on intelligent gravimetric analysis, simulation studies, facile synthesis, and very good IAST selectivity. Experimental results showed good butadiene uptake capacity of Ni-ZIF-8 of 7.41 mol/kg, which is 42% higher than pure ZIF-8. Additionally, Ni-ZIF-8 exhibits IAST selectivities of 2826 and 3302 at 0.1 bar, at 25 and 45 °C respectively, for 20% BD/N 2 adsorption. The molecular simulation results showed that Ni-ZIF-8 has binding energies of 65.25, 9.54 kJ/mol, while ZIF-8 has 56.07, 15.03 kJ/mol for butadiene, and nitrogen, respectively. This strongly supported the experimental results. To the best of our knowledge, Ni-ZIF-8 showed the best working capacity of 5.91 mol/kg for butadiene among all the reported adsorbents. Moreover, dynamic adsorption experiments revealed that butadiene could be recovered from BD/N 2 mixtures at room temperature, suggesting great potential for industrial BD/N 2 separation.
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JOURNAL OF THE ELECTROCHEMICAL SOCIETY
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2020
·Vol. 167
·期 6
·067525
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IF 3.721
Yi Xiu,Ruiping Luo,Baoqing Han,Lu Liu,Hongsu Wang
There is an urgent need to develop convenient, rapid and sensitive detection methods to determine antibiotic residues in food. New Delhi metal-β-lactamase-1 (NDM-1) is a β-lactamase enzyme that catalyzes removal of all β-lactam antibiotics other than aztreonam via a spectral hydrolysis mechanism. In the present study, a new biosensor based on NDM-1 was designed and tested to detect penicillin antibiotics namely penicillin sodium (Pen G) and ampicillin sodium (AMP) without using any pH redox probe. The glassy carbon electrode (GCE) was modified by electro-polymerization of methylene blue (PMB), and the biosensor (NDM-1/PMB/GCE) was prepared by immobilizing NDM-1 enzyme with glutaraldehyde (GA). Penicillin was detected by differential pulse voltammetry (DPV). This study seems to be one of the first kind to apply NDM-1 enzyme to detect antibiotic residues in food. It can be used repeatedly and can successfully detect penicillin in actual milk samples by spike recovery experiment.
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CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY
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2020
·Vol. 98
·期 6
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IF 1.946
Di Wang,Meilan Zhou,Yan Wang,Shiren Sun
Xerostomia is a self-conscious symptom. High-mobility group box 1 (HMGB1) promotes pro-inflammatory effects in many diseases. This study aimed to clarify the role of HMGB1 in Sjögren syndrome (SS)-triggered xerostomia. Nonobese diabetic (NOD)/Ltj mice were used to establish an SS-triggered xerostomia model. The results showed that saliva production was decreased and anti-Sjögren syndrome B (anti-SSB) level was increased in SS. PCR, Western blot, and immunohistochemistry experiments indicated that the HMGB1 and aquaporin 5 (AQP5) levels were enhanced and diminished in SS compared with those in the control, respectively. While the mice were treated with anti-HMGB1, xerostomia was reversed due to the elevated saliva production and reduced anti-SSB level. In addition, it was found that the inhibition of HMGB1 restrained the toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) axis activation. The TLR4 and p-IκB levels were alleviated, while the IκBα and NF-κB p65 levels were augmented. The NF-κB p65 binding activity was attenuated via the electrophoretic mobility shift assay (EMSA) after anti-HMGB1 treatment. Moreover, the repression of HMGB1 facilitated the expression of AQP5. These findings demonstrate that suppression of HMGB1 ameliorates SS-triggered xerostomia via suppressing the HMGB1/TLR4/NF-κB signaling pathway and upregulating AQP5 expression.
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SENSORS AND ACTUATORS B-CHEMICAL
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2021
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IF 7.46
Bin Zhou,Lei Lin,Bingzhi Li
Flap endonuclease 1 (FEN1) is a nuclease overexpressed in cells with a high replicate rate, which has been recognized as a potential biomarker in the molecular diagnosis of cancers. In this work, we developed a fluorescent biosensor based on exponential amplification reaction (EXPAR) to realize the rapid and sensitive detection of FEN1. A DNA probe specific for FEN1 is used for the generation of reporter DNA (rDNA), and then the rDNA hybridizes with a template, triggering EXPAR to produce substantial rDNA exponentially. However, when no FEN1 is in the system, the EXPAR will not be initiated because of the lack of rDNA. Derived from the high amplification efficiency of EXPAR, the rapid quantification of FEN1 with a limit of detection (LOD) of 0.5 fM was realized. It is also revealed that this biosensor exhibits good selectivity towards FEN1 under the challenge from real samples including extracts of cells and solid tumors. Furthermore, this sensor was reengineered for the analysis of FEN1 inhibitors, which shows promise in the screening and evaluation of potential drugs targeting FEN1. This work integrates EXPAR into the biosensing of FEN1 for the first time, which provides a promising tool for FEN1-related biomedical investigations.
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INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2021
·Vol. 22
·期 21
·11466
·
IF 5.924
Miaomiao Qi,Xiang Liu,Ying Zhou,Haoyu Wang,Ying Zhao,Jing Ren,Jin Xiang
G protein-coupled estrogen receptor 1 (GPER1) is a potential therapeutic target for treating triple-negative breast cancers (TNBC). However, modulators for GPER1 that can be used to treat TNBC have not appeared. Berberine (BBR) is a bioactive isoquinoline alkaloid with high oral safety. In recent years, BBR has shown an inhibitory effect on TNBC tumors such as MDA-MB-231, but the molecular target remains unclear, which hinders related clinical research. Our work proved that BBR is a modulator of GPER1 that can inhibit cell viability, migration, and autophagy of MDA-MB-231 cells. The inhibitory effect of BBR on MDA-MB-231 cells has a dependence on estrogen levels. Although BBR promoted the proteasome, which is a major factor in the degradation of GPER1, it could still induce the protein level of GPER1. Correspondingly, the transcription of cellular communication network factor 2 (CCN2) was promoted. BBR could bind to GPER1 directly and change the secondary structure of GPER1, as in the case of 17β-estradiol (E2). In addition, BBR induced not only a high degree of co-localization of GPER1 and microtubule-associated protein 1 light chain 3 (MAP1LC3), but also the accumulation of sequestosome 1 (SQSTM1/p62) by the inhibition of the nuclear translocation of the nuclear factor-kappa B (NF-κB) subunit (RELA/p65), which indicates NF-κB inhibition and anti-cancer effects. This result proved that the promotional effect of BBR on the GPER1/NF-κB pathway was closely related to its inhibitory effect on autophagy, which may serve as a new mechanism by which to explain the inhibitory effect of BBR on MDA-MB-231 cells and expand our understanding of the function of both BBR and GPER1.Keywords:berberine;binding;co-localization;GPER1;MAP1LC3;NF-κB
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Journal of Physical Chemistry C
·
2021
·
IF 4.126
Fuyong Zhang,Wei Zhou,Xuewei Xiong,Yuhao Wang,Kang Cheng,Jincan Kang,Qinghong Zhang,Ye Wang
Catalytic transformation of CO2 into chemicals in large demand such as ethanol has attracted much research attention under the background of establishing carbon-neutral societies. Supported Rh catalysts are promising candidates for the hydrogenation of CO2 to ethanol but suffer from low ethanol productivity and poor catalyst stability. Here, we report that zeolite silicalite-1 embedded Na-promoted Rh nanoparticles (Na-Rh@S-1) demonstrate high productivity and stability for CO2 hydrogenation to ethanol. The ethanol selectivity of 24% was attained at a CO2 conversion of 10%, and the space-time yield of ethanol reached 72 mmol gRh–1 h–1, which outperformed most of the Rh-based catalysts reported to date. While a reference catalyst prepared by impregnation underwent deactivation, the Na-Rh@S-1 catalyst was stable for at least for 100 h owing to the confinement effect. The Na+ modifier played crucial roles in enhancing the CO2 conversion and ethanol selectivity by suppressing methane formation. The characterizations suggest that the presence of Na+ enables the coexistence of Rh0 and Rh+ and enhances CO2 adsorption, thus boosting ethanol formation. A comparative study between CO and CO2 hydrogenation reveals that the Na-Rh@S-1 catalyst is significantly more active and selective toward CO2 hydrogenation to ethanol.
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ARCHIVES OF ORAL BIOLOGY
·
2021
·
IF 2.635
Yujia Cui,Mingru Bai,Daimo Guo,Yueyi Yang,Haoran Chen,Jianxun Sun,Jing Xie,Xuedong Zhou
Objective Insulin-like growth factor 1 (IGF1) is one of the vital factors in regenerative endodontics . Previous studies have focused on the role of IGF1 in the mineralization of dental tissues. However, the role of IGF1 in the neural differentiation of dental stem cells was little discussed. Design IGF1 was overexpressed in human stem cells from the apical papilla (hSCAPs) by lentivirus and knocked down in hSCAPs by small interfering RNA . The neural differentiation level of hSCAPs was investigated histologically by HE staining and Nissl staining after neural induction for 3 days. The expression of proteins was examined by western blot and immunofluorescence. Results IGF1 promoted neural differentiation of hSCAPs, more cell processes and Nissl-positive body stained cells. IGF1 overexpression could both promote glial differentiation in hSCAPs, characterized by the increase of S100β and GFAP proteins, and neuronal differentiation , characterized by the increase of βIII-tubulin and functional GAD67/vGLUT1 proteins. Conversely, IGF1 knockdown suppressed both glial and neuronal differentiation. IGF1 activated AKT to regulate the early neural differentiation of hSCAPs. Conclusions The results indicate IGF1 could promote neural differentiation of hSCAPs by activating AKT signaling and provide a cue for the candidate of induced neural seeding cells in regenerative endodontics.
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PHYTOMEDICINE
·
2019
·
IF 4.18
Dan Chen,Ya-Xian Wu,Yu-bao Qiu,Bin-bin Wan,Gang Liu,Jun-liang Chen,Mu-dan Lu,Qing-feng Pang
Background Hypoxia is commonly existed in tumors and lead to cancer cell chemo/radio-resistance. It is well-recognized that tumor hypoxia is a major challenge for the treatment of various solid tumors . Hyperoside (quercetin-3-O-galactoside, Hy) possesses antioxidant effects and has been reported to protect against hypoxia/reoxygenation induced injury in cardiomyocytes . Therefore, Hy may be attractive compound applicable to hypoxia-related diseases . Purpose This study was designed to determine the role of Hy in hypoxia-induced proliferation of non-small cell lung cancer cells and the underlying mechanism. Study Design and Methods A549, a human non-small cell lung cancer (NSCLC) cell line, was used in the present study. 1% O 2 was used to mimic the in vivo hypoxic condition of NSCLC. The potential mechanisms of Hy on hypoxia-induced A549 survival and proliferation, as well as the involvement of AMPK/HO-1 pathway were studied via CCK-8 assay, EdU staining, flow cytometry, qRT-PCR and western blot . Results We showed that pretreatment with Hy suppressed hypoxia-induced A549 survival and proliferation in dose-dependent manner. In terms of mechanism, hypoxia-treated A549 showed the lower AMPK phosphorylation and the reduced HO-1 expression, which were reversed by Hy pretreatment. Both AMPK inhibitor (Compound C) and HO-1 activity inhibitor (Zinc protoporphyrin IX) abolished Hy-evoked A549 cell death under hypoxia stimuli. Of note, Ferrous iron contributed to Hy-induced A549 cell death under hypoxia, while Hy had no effect on lipid peroxidation under hypoxia. Conclusion Taken together, our results highlighted the beneficial role of Hy against hypoxia-induced A549 survival and proliferation through ferrous accumulation via AMPK/HO-1 axis.
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