Herein, a nickel coordination polymer (CP 1), {Ni(1,4-bib)
(TPA-Cl
)·H
O}
(1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene, H
TPA-Cl
= 2,5-dichloro-terephthalic acid), has been synthesized under ...solvothermal conditions. The structure of CP 1 is a 3D 3-fold interpenetrating framework with the sqc12 topology. The thermal stability and luminescence properties of CP 1 were investigated. Scanning electron microscopy (SEM) images of this material display that it possesses an irregular block 3D structure. Interestingly, CP 1 can serve as a multifunctional material via its luminescence sensing, electrochemical sensing, and photocatalytic properties. The experimental results indicate that CP 1 is an efficient luminescent sensor for the detection of Fe
ions in an aqueous solution. In addition, CP 1 exhibits a sensitive and rapid electrochemical response to nitrite ions in water solution. The photocatalytic activities of CP 1 were evaluated in the degradation of different dye contaminants (MB, RhB, and MO), and the results demonstrate that its photocatalytic efficiency for the degradation of MB is highest (92.1% for MB, 85.7% for RhB, and 86.2% for MO). The effects of different dyes, different powers of UV light, and different amounts of catalyst CP 1 on the photocatalytic efficiency were also explored. Finally, the mechanism of the luminescence quenching effect toward Fe
ions, electroreduction of nitrite ions, and photocatalytic degradation of different dyes have been investigated in detail.
Photocatalytic hydrogen (H2) evolution coupled with selective organic synthesis over semiconductor-based photocatalysts is attractive because the clean H2 fuel and value-added chemicals can be ...coproduced at ambient conditions using solar light as the sole energy input. Here, we report the efficient merging catalysis of photoredox-driven dehydrogenative C–C coupling of benzyl alcohol (BA) into hydrobenzoin (HB) and H2 evolution over the SiO2-supported semiconductor CdS quantum dots (QDs) at ambient temperature and pressure. In this system, we utilize the judicious interfacial engineering approach to rationally assemble CdS QDs onto the spherical SiO2 support by which CdS QDs can recycle the scattered light in the near field of SiO2 and achieve the significantly enhanced light-harvesting capability and more efficient generation of charge carriers. Consequently, as compared to bare CdS QDs and Pt/SiO2, the SiO2-supported CdS QDs (CdS/SiO2) exhibits distinctly boosted photoredox-catalyzed activity and stability for C–C coupling of BA into HB and H2 evolution. The underlying origin toward an efficient C–C coupling reaction over CdS/SiO2 is analyzed accordingly. This work would open a conceptual vista of utilizing a near-field scattering-promoted optical absorption model and nanoscale interfacial assembly method to maneuver the light-capturing property of semiconductor QDs without size alteration for solar fuel production and organic synthesis of fine chemicals.
•Mixed collectors exhibit selectivity in flotation separation of muscovite from quartz.•The ratio of the mixed collectors is an important criterion in the flotation tests.•Adsorption mechanism of ...mixed collectors systems is studied.•Mixed collectors absorb on muscovite by electrostatic and chemical adsorption.
The flotation separation of muscovite from quartz was investigated using mixed sodium oleate/dodecylamine acetate (NaOL/DDA) collectors. The experiments were conducted on single minerals and on a mixture of minerals, and their collecting performances were studied by means of Fourier transform infrared (FTIR) spectroscopy, zeta potential technique and X-ray photoelectron spectroscopy (XPS). The results show that neither muscovite nor quartz is floated with NaOL alone, while using DDA alone, they can be separated only at strong acid conditions (pH<3). Mixed NaOL/DDA collectors exhibits excellent performance in the flotation separation of muscovite from quartz at pH 10. The ratio of the mixed collectors is found to be an important criterion in the flotation tests. The best separation result (muscovite recovery of 80% and quartz recovery of 10%) could be achieved with NaOL/DDA molar ratios of 3/1 and 2/1 at pH 10. The co-adsorption of NaOL and DDA is found on muscovite surface by strong electrostatic interaction, hydrogen bonding and chemical adsorption. This study may provide guidance for the flotation mechanism and application of mixed anionic/cationic collectors.
Background/Aims: Angiotensin (Ang) II plays vital roles in vascular inflammation and remodeling in hypertension. Phenotypic transformation of vascular smooth muscle cells (VSMCs) is a major ...initiating factor for vascular remodeling. The present study was designed to determine the roles of NLRP3 inflammasome activation in Ang II-induced VSMC phenotypic transformation and vascular remodeling in hypertension. Methods: Primary VSMCs from the aorta of NLRP3 knockout (NLRP3-/-) mice and wild-type (WT) mice were treated with Ang II for 24 h. Subcutaneous infusion of Ang II via osmotic minipump for 2 weeks was used to induce vascular remodeling and hypertension in WT and NLRP3-/- mice. Results: NLRP3 gene deletion attenuates Ang II-induced NLRP3 inflammasome activation, phenotypic transformation from a contractile phenotype to a synthetic phenotype and proliferation in primary mice VSMCs. Ang II-induced hypertension and vascular remodeling in WT mice were attenuated in NLRP3-/- mice. Furthermore, Ang II-induced NLRP3 inflammasome activation, phenotypic transformation and proliferating cell nuclear antigen (PCNA) upregulation were inhibited in the media of aorta of NLRP3-/- mice. Conclusions: NLRP3 inflammasome activation contributes to Ang II-induced VSMC phenotypic transformation and proliferation as well as vascular remodeling and hypertension.
Two new Cd(II) coordination polymers, namely {Cd(L)(tp)·2H2O}n(1) and {Cd(L)(5-hip)·2.66H2O}n (2), where L = 1,3-bis(5,6-dimethylbenzimidazol-1-yl)-2-propanol, H2tp = terephthalic acid and 5-H2hip ...= 5-hydioxyisophthalic acid, were hydrothermally synthesized and characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analyses. 1 possesses a 4,4-connected two-dimensional 4,4L10 network with a point symbol of {32·4·62·7}2{32·62·72}. 2 displays a 3,5-connected three-dimensional 3,5T1 framework with a point symbol of {42·65·83}{42·6}. 1 and 2 attained highly photocatalytic efficiency toward the decomposition of methylene blue (MB) under UV light irradiation. Furthermore, 2 was successfully applied in selective sensing of Fe3+ and Cr2O72- ions with the low detection limit 1.56 × 10−7 M and 2.79 × 10−7 M, respectively.
Two coordination polymers based on 1,3-bis(5,6-dimethylbenzimidazol-1-yl)-2-propanol and different aromatic dicarboxylate ligands have been synthesized and characterized. The photocatalytic properties of 1 and 2 for degradation of MB upon UV light have been examined. Furthermore, the luminescence sensing for Fe3+ and Cr2O72- of 2 were investigated in detail. Display omitted
•Two Cd(II) CPs were synthesized and characterized.•New 2D and 3D coordination framework were presented.•1-2 display highly photocatalytic efficiencies for degrading MB.•2 shows high selectivity and sensitivity towards luminescent detection of Fe3+ and Cr2O72-.
Aims
The pathogenesis of diabetic peripheral neuropathy (DPN) is complex, and its treatment is extremely challenging. MicroRNA‐7a‐5p (miR‐7a‐5p) has been widely reported to alleviate apoptosis and ...oxidative stress in various diseases. This study aimed to investigate the mechanism of miR‐7a‐5p in DPN.
Methods
DPN cell model was constructed with high‐glucose–induced RSC96 cells. Cell apoptosis and viability were detected by flow cytometry analysis and cell counting kit‐8 (CCK‐8) assay respectively. The apoptosis and Jun N‐terminal kinase (JNK)/c‐JUN signalling pathway‐related proteins expression were detected by Western blotting. The intracellular calcium content and oxidative stress levels were detected by flow cytometry and reagent kits. Mitochondrial membrane potential was evaluated by tetrechloro‐tetraethylbenzimidazol carbocyanine iodide (JC‐1) staining. The targeting relationship between miR‐7a‐5p and voltage‐dependent anion‐selective channel protein 1 (VDAC1) was determined by RNA pull‐down assay and dual‐luciferase reporter gene assay. The streptozotocin (STZ) rat model was constructed to simulate DPN in vivo. The paw withdrawal mechanical threshold (PTW) was measured by Frey capillary line, and the motor nerve conduction velocity (MNCV) was measured by electromyography.
Results
MiR‐7a‐5p expression was decreased, while VDAC1 expression was increased in HG‐induced RSC96 cells and STZ rats. In HG‐induced RSC96 cells, miR‐7a‐5p overexpression promoted cell proliferation, inhibited apoptosis, down‐regulated calcium release, improved mitochondrial membrane potential and repressed oxidative stress response. MiR‐7a‐5p negatively regulated VDAC1 expression. VDAC1 knockdown improved cell proliferation activity, suppressed cell apoptosis and mitochondrial dysfunction by inhibiting JNK/c‐JUN pathway activation. MiR‐7a‐5p overexpression raised PTW, restored MNCV and reduced oxidative stress levels and nerve cell apoptosis in STZ rats.
Conclusion
MiR‐7a‐5p overexpression ameliorated mitochondrial dysfunction and inhibited apoptosis in DPN by regulating VDAC1/JNK/c‐JUN pathway.
Two new Cd2+ coordination polymers (CPs), namely {Cd(L)(1,4-PDA)·0.7(C2H5OH)}n (1) and {Cd(L)0.5(1,8-NDC)·H2O}n (2) L = 1,4-bis(5,6-dimethybenzimidazol-1-yl)-2-butene, 1,4-H2PDA = ...1.4-phenylenediacetic acid, 1,8-H2NDC = 1,8-naphthalenedicarboxylic acid, were hydrothermally synthesized and characterized. 1 is a (4,4)-layered structure and further extended into a 3D supramolecular network via π–π stacking interactions. 2 features a 2D (3,4)-connected 3,4L83 framework. 1 and 2 can act as luminescence sensors for detecting acetylacetone (acac) and Fe3+ with high sensitivity, selectivity and recyclability. This is the first dual fluorosensors employing CPs for the detection of Fe3+ and acac. The mechanism for the luminescent sensing of acac and Fe3+ was suggested.
Berberine (BH) is an important traditional medicinal herb endowed with diverse pharmacological and biological activities. In this work, the binding characteristics and molecular mechanism of the ...interaction between the BH and herring sperm DNA were explored by UV–vis absorbance and fluorescence spectroscopy. In the mechanism discussion, fluorescence quenching, absorption spectra, competition experiment, and iodide quenching experiment studies hinted at an intercalative mode of binding for BH to DNA. Fluorescence studies revealed the binding constant (K) of BH–DNA was ∼104 L·mol–1. The effects of temperature, chemical denaturants, thermal denaturation, and pH were studied to show the factors of the interaction and provided further support for the intercalative binding mode. The results of thermodynamic parameters ΔG, ΔH, and ΔS at different temperatures indicated that the hydrogen bonds and van der Waals interactions played major roles in the reaction, and the effect of ionic strength indicated that electrostatic attraction between the BH and DNA was also a component of the interaction.
Objective
Obesity can affect periodontal tissues and exacerbate periodontitis. Pyroptosis, a newly identified type of inflammatory cell death, is involved in the development of periodontal ...inflammation. The saturated fatty acid palmitic acid (PA) is elevated in obese patients. The effect of PA on pyroptosis in periodontal ligament cells (PDLCs) and its underlying mechanisms remain unknown.
Materials and Methods
Human PDLCs were isolated from healthy individuals and cultured for experiments. The effects of PA on PDLC pyroptosis and the underlying mechanisms were examined by transmission electron microscopy, quantitative real‐time PCR and western blotting.
Results
The morphology of PDLCs in the PA group indicated pyroptotic characteristics, including swollen cells, plasma membrane rupture and changes in subcellular organelles. PA induced inflammatory responses in PDLCs, as indicated by an increase in IL‐1β in the cell culture supernatant. Furthermore, we found that the pyroptosis‐related proteins caspase‐1, caspase‐4 and GSDMD were involved in PA‐induced cell death. GSDMD and caspase‐4 inhibitors alleviated pyroptotic death of PDLCs. Moreover, PA promoted NF‐κB P65 phosphorylation. A NF‐κB inhibitor decreased IL‐1β expression and partly rescued cell death induced by PA.
Conclusion
PA activated the NF‐κB pathway and induced the inflammatory response in PDLCs. Caspase‐4/GSDMD mediated PDLC pyroptosis induced by PA.
PDF
