Publications by authors named "Honglei Shen"

Introduction: Lung injury, a common complication of sepsis, arises from elevated reactive oxygen species (ROS), mitochondrial dysfunction, and cell death driven by inflammation. In this study, a novel class of ultrasmall nanoparticles (CuO USNPs) was developed to address sepsis-induced lung injury (SILI).

Methods: The synthesized nanoparticles were thoroughly characterized to assess their properties.

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Dual-atom catalysts (DACs) originate unprecedented reactivity and maximize resource efficiency. The fundamental difficulty lies in the high complexity and instability of DACs, making the rational design and targeted performance optimization a grand challenge. Here, an atomically dispersed Pd DAC with an in situ generated Pd─Pd bond is constructed by a dynamic strategy, which achieves high activity and selectivity for semi-hydrogenation of alkynes and functional internal acetylene, twice higher than commercial Lindlar catalyst.

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Exploiting emissive hydrophobic nanoclusters for hydrophilic applications remains a challenge because of photoluminescence (PL) quenching during phase transfer. In addition, the mechanism underlying PL quenching remains unclear. In this study, the PL-quenching mechanism was examined by analyzing the atomically precise structures and optical properties of a surface-engineered Ag nanocluster with an all-around-carboxyl-functionalized surface.

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Although several silver-based nanoclusters have been controllably prepared and structurally determined, their electrochemical catalytic performances have been relatively unexplored (or showed relatively weak ability towards electro-catalysis). In this work, we accomplished the step-by-step enhancement of the electrocatalytic hydrogen evolution reaction (HER) efficiency based on an Ag cluster template. A combination of atomically precise operations, including the kernel alloying, ligand engineering, and surface activation, was exploited to produce a highly efficient PtAg-BTT-Mn(10) nano-catalyst towards HER, derived from both experimental characterization and theoretical modelling.

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The determination of surface-active sites in metal nanoclusters is of great significance for the in-depth understanding of structural evolutions and physicochemical property mechanisms. In this work, the surface-active sites of the AuAg(DMBT)(DPPOE) cluster template towards metal-/ligand-exchange reactions were unambiguously identified at the atomic level. The active-site tailoring of this nanocluster gave rise to three derivative nanoclusters, AuAgCu(DMBT)(DPPOE), AuAg(DMBT)(DCBT)(DPPOE), and AuAg(DCBT)(DPPOE).

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Developing new approaches to fulfill the enantioseparation of nanocluster racemates and construct cluster-based nanomaterials with optical activity remains highly desired in cluster science, because it is an essential prerequisite for fundamental research and extensive applications of these nanomaterials. We herein propose a strategy termed "active-site exposing and partly re-protecting" to trigger the symmetry breaking of highly symmetrical nanoclusters and to render cluster crystals optically active. The vertex PPh of the symmetrical Ag(SSR)(PPh) (SSR = 1, 3-benzenedithiol) nanocluster was firstly dissociated in the presence of counterions with large steric hindrance, and then the exposed Ag active sites of the obtained Ag(SSR) nanocluster were partly re-protected by Ag, yielding an Ag(SSR)-Ag nanocluster with a symmetry-breaking construction.

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Silver nanoclusters have received unprecedented attention in cluster science owing to their promising functionalities and intriguing physical/chemical properties. However, essential instability significantly impedes their extensive applications. We herein propose a strategy termed "surface environment complication" to endow Ag nanoclusters with high robustness.

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Surface modification has served as an efficient approach to dictate nanocluster structures and properties. In this work, based on an Ag nanocluster template, the effects of surface modification on intracluster constructions and intercluster packing modes, as well as the properties of nanoclusters or cluster-based crystallographic assemblies have been investigated. On the molecular level, the Ag nanocluster with larger surface steric hindrance was inclined to absorb more small-steric chlorine but less bulky thiol ligands on its surface.

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The structural determination of metastable nanoclusters remains challenging, which impedes the in-depth understanding of their structural evolution. Herein, based on a case study of Pd1Au9, we present a "cocrystallization-driven stabilization" approach to stabilize the metastable nanocluster and then determine its atomically precise structure. The [Pd1Au9(TFPP)7Br2]+ nanocluster is unstable in solution and would spontaneously convert to Pd2Au23(TFPP)10Br7.

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The determination of active sites in metal nanoclusters is of great significance for the in-depth understanding of the structural evolution and the mechanism of physicochemical properties. In this work, the surface active Ag(SR) units of the AgCl(S-Adm) nanocluster are determined, and the active-site tailoring of this nanocluster gives rise to two derivative nanoclusters, i.e.

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A newly isolated Galactomyces geotrichum ZJUTZQ200 strain containing an epoxide hydrolase was used to resolve racemic ethyl 3-phenylglycidate (rac-EPG) for producing (2R,3S)-ethyl-3-phenylglycidate ((2R,3S)-EPG). G. geotrichum ZJUTZQ200 was verified to be able to afford high enantioselectivity in whole cell catalyzed synthesis of this chiral phenylglycidate synthon.

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A newly isolated Aspergillus niger strain containing epoxide hydrolase was used to resolve racemic glycidyl azide and four derivatives to the (R)-enantiomers. After optimization of the biotransformation conditions, (R)-glycidyl azide was produced with good enantioselectivity (e.e.

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Talaromyces flavus containing a constitutive epoxide hydrolase (EH) resolved racemic benzyl glycidyl ether and nine derivatives into their (R)-enantiomers. After optimization of the fermentation conditions, the specific EH activity and biomass concentration were improved from 13.5 U/g DCW and 14.

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Dietary antioxidants play an important role against oxidation, an underlying mechanism in the incidence of chronic diseases. Greens+ is a commercially available preparation containing a variety of plant-derived ingredients. The aim of the current study was to evaluate the antioxidant potential of the methanolic extract of greens+ powder using in vitro and in vivo techniques.

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Background: Several functions have been attributed to the BRCA1 protein. A recent study suggests that BRCA1 is involved in the cellular antioxidant response by inducing the expression of genes involved in the antioxidant defense system and thus conferring resistance to oxidative stress. It is possible that individuals with a BRCA1 mutation might be susceptible to the effects of oxidative stress.

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Lycopene is a bioactive carotenoid present in many fruits and vegetables. Tomatoes constitute the major dietary source of lycopene. Recent evidence shows lycopene to be associated with several health benefits.

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