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Most of advanced hypopharyngeal squamous cell carcinoma (HSCC) are resistant to chemotherapy, and there is still lack of effective treatment for HSCC now. The present study aimed to investigate whether downregulation of RNA-binding motif protein 17 (RBM17) could enhance cisplatin sensitivity and inhibit cell invasion in HSCC and the underlying mechanism. We observed that RBM17 was upregulated in tumor tissues and associated with poor progression. Treatment of FaDu cells with cisplatin increased RBM17 expression in mRNA levels. Downregulation of RBM17 enhanced cisplatin-mediated inhibition of FaDu cells. In addition, downregulation of RBM17 effectively suppressed tumor cell migration and invasion through the reversion of epithelial–mesenchymal transition. Moreover, downregulation of RBM17 could significantly slow tumor growth in FaDu xenograft tumor model. Liquid chromatography–mass spectrometry/mass spectrometry detection and independent PRM analysis showed that 21 differentially expressed proteins were associated with the downregulation of RBM17. Taken together, our study implied that downregulation of RBM17 could serve as a novel approach to enhance cisplatin sensitivity in HSCC.

Designing composite catalysts that harness the strengths of individual components while mitigating their limitations is a fascinating yet challenging task in catalyst engineering. In this study, we aimed to enhance the catalytic performance by anchoring ZIF-67 nanoparticles of precise sizes onto lamella Si-MWW zeolite surfaces through a stepwise regrowth process. Co ions were initially grafted onto the zeolite surface using ultrasonication, followed by a seed-assisted secondary growth method. Si-MWW proved to be the ideal zeolite support due to its thin layered structure, large external surface area and substantial lateral dimensions. The abundant Si–OH groups on its surface played a crucial role in securely binding Co ions, limiting size growth and preventing undesirable ZIF-67 aggregation. The resulting ZIF-67/MWW composite with finely dispersed nano-scale ZIF-67 particles exhibited a remarkable catalytic performance and stability in the aldol condensation reactions involving acetone and various aldehydes. This approach holds promise for designing MOF/zeolite composite catalysts. [ABSTRACT FROM AUTHOR]

The 20th National Congress of the Communist Party of China proposed accelerating the promotion of Chinese-style modernization, placing higher requirements on regional economic development. In this context, interregional industrial convergence has become a new driving force for achieving high-quality economic development and regional industrial transformation and upgrading. Using the 2017 interregional input-output table provided by Carbon Emission Accounts and Datasets (CEADs), this study constructs a directed weighted network from both the supply side and the demand side, with "province-industry" as the node and the real flow between industries as the edge weight. Network analysis is used to investigate the overall status of industrial convergence in China, as well as differences according to industry and region. Finally, an exponential random graph model (ERGM) is used to examine the influencing factors and effects of network formation. The results show the following: (1) the industrial convergence relationship between regions in China is transitive and reciprocal, and the overall tendency of the network is one in which output capacity is greater than absorption capacity. (2) The marginal flow of manufacturing and services occupies an absolute advantage in China's industrial convergence network, in which mid-end manufacturing and producer services are the most prominent. (3) Industrial convergence between provinces has formed a hierarchical spatial layout of "output-conduction-absorption". In the absorption layer, the breadth and depth of Beijing's industrial integration are characterized by absorption-dominant development. In the output layer, Shanghai's capital-intensive industries have a strong external radiation capacity and generally show open-led development. (4) Interregional industrial convergence tends to occur in areas with similar economic levels and output value levels, showing a coordinated development trend of high-level output and low-level absorption, which is also affected by location proximity relationships, regional technology gaps, and employment population gaps. This research shows that China's inter-provincial industrial convergence network generally shows the characteristics of spatial hierarchy, significant industry differences and multi-factor drivers. [ABSTRACT FROM AUTHOR]

β-Diketones are one of the most widely used ligands for sensitizing the luminescence of lanthanide complexes due to their excellent sensitization abilities. However, the difficulties in introducing chiral groups to take part in the electronic transitions of conjugated systems limit their application in lanthanide circularly polarized luminescence (CPL) materials. In view of the inherent chirality of the helical structure, herein, a pair of homochiral quadruple-stranded helicates, Eu2L4, is assembled based on chiral bis-β-diketonate ligands, wherein the two point chirality centers in the spacer preorganize the helical conformation of the ligand (3S,4S)/(3R,4R)-3,4-bis(4,4′-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenoxyl)-1-benzylpyrrolidine, LSS/LRR. X-ray crystallographic analyses reveal that the R,R configurations of the chiral carbons in the spacer induce the M helical sense of the ligand, while the S,S configurations induce the P helical sense. Through the comprehensive spectral characterization in combination with semiempirical geometry optimization using the Sparkle/RM1 model, it is confirmed that the preorganized ligands successfully control the homochirality of the helicates. Moreover, the mirror-image CD and CPL spectra and NMR measurements confirm the formation of enantiomeric pairs and their diastereopurities in solution. Detailed photophysical and chiroptical characterization studies reveal that the helicates not only exhibit intense circularly polarized luminescence (CPL) with ‖glum‖ values reaching 0.10, but also show a high luminescence quantum yield of 34%. This study effectively combines the helical chirality of the helicates with the excellent sensitization ability of the β-diketones, providing an effective strategy for the syntheses of chiral lanthanide CPL materials. [ABSTRACT FROM AUTHOR]

The construction of defective sites is one of the effective strategies to create high-activity Metal-Organic frameworks (MOFs) catalysts. However, traditional synthesis methods usually suffer from cumbersome synthesis steps and disordered defect structures. Herein, a cluster-cluster co-nucleation (CCCN) strategy is presented that involves the in situ introduction of size-matched functional polyoxometalates (H 6 P 2 W 18 O 62 , {P 2 W 18 }) to intervene the nucleation process of cluster-based MOFs (UiO-66), achieving one-step inducement of exposed defective sites without redundant post-processing. POM-induced UiO-66 ({P 2 W 18 }-0.1@UiO-66) exhibits a classical reo topology for well-defined cluster defects. Moreover, the defective sites and the interaction between POM and skeletal cluster nodes are directly observed by Integrated Differential Phase Contrast in Scanning Transmission Electron Microscopy (iDPC-STEM). Owing to the molecular-level proximity between defective sites and POM in the same nano-reaction space, {P 2 W 18 }-0.1@UiO-66 exhibits efficient tandem catalysis in the preparation of γ-valerolactone (γ-GVL) from laevulinic acid (LA) by the combination of Lewis and Brønsted acids with 11 times higher performance than defective UiO-66 formed by conventional coordination modulation strategy. The CCCN strategy is applicable to different POM and has the potential to be extended to other cluster-based MOFs, which will pave a new way for the construction of functional MOFs with multi-centered synergistic catalysis., (© 2024 Wiley‐VCH GmbH.)

Designing composite catalysts that harness the strengths of individual components while mitigating their limitations is a fascinating yet challenging task in catalyst engineering. In this study, we aimed to enhance the catalytic performance by anchoring ZIF-67 nanoparticles of precise sizes onto lamella Si-MWW zeolite surfaces through a stepwise regrowth process. Co ions were initially grafted onto the zeolite surface using ultrasonication, followed by a seed-assisted secondary growth method. Si-MWW proved to be the ideal zeolite support due to its thin layered structure, large external surface area and substantial lateral dimensions. The abundant Si-OH groups on its surface played a crucial role in securely binding Co ions, limiting size growth and preventing undesirable ZIF-67 aggregation. The resulting ZIF-67/MWW composite with finely dispersed nano-scale ZIF-67 particles exhibited a remarkable catalytic performance and stability in the aldol condensation reactions involving acetone and various aldehydes. This approach holds promise for designing MOF/zeolite composite catalysts.

Traditional polymer membranes exhibit a constant structure that makes adjustment of the filtration process difficult, such as flux changing and contaminant cleaning. Inspired by the automatically closing behavior of leaf stomata under strong light, we prepared a membrane with thermo- and photosensitivities, whose microstructure, as well as filtration properties, could be controlled by adjusting the light condition. The membrane was fabricated by the immersion phase inversion method with a casting solution of polyvinylidene fluoride- g -poly( N -isopropylacrylamide) (PVDF- g -PNIPAAm) and graphene oxide (GO) nanosheets. Additionally, the membrane could be heated to a high temperature in a short time under illumination, causing shrinkage of its PNIPAAm chains and expansion of its membrane pores. On the basis of the reversible photoinduced structural transformation, the membrane exhibited a high water gating ratio under the switching of light on/off. Moreover, we proposed a novel and simple method to clear the contaminant from the pores of the membrane via light, which we named "light-cleaning". Light-cleaning had a flux recovery rate of 99.2%, substantially higher than that of back-washing (62%). This work not only extends the controllability and functionality of the polymer membrane but also develops a new membrane cleaning system.

β-Diketones are one of the most widely used ligands for sensitizing the luminescence of lanthanide complexes due to their excellent sensitization abilities. However, the difficulties in introducing chiral groups to take part in the electronic transitions of conjugated systems limit their application in lanthanide circularly polarized luminescence (CPL) materials. In view of the inherent chirality of the helical structure, herein, a pair of homochiral quadruple-stranded helicates, Eu 2 L 4 , is assembled based on chiral bis-β-diketonate ligands, wherein the two point chirality centers in the spacer preorganize the helical conformation of the ligand (3S,4S)/(3R,4R)-3,4-bis(4,4'-bis(4,4,4-trifluoro-1,3-dioxobutyl)phenoxyl)-1-benzylpyrrolidine, L SS /L RR . X-ray crystallographic analyses reveal that the R,R configurations of the chiral carbons in the spacer induce the M helical sense of the ligand, while the S,S configurations induce the P helical sense. Through the comprehensive spectral characterization in combination with semiempirical geometry optimization using the Sparkle/RM1 model, it is confirmed that the preorganized ligands successfully control the homochirality of the helicates. Moreover, the mirror-image CD and CPL spectra and NMR measurements confirm the formation of enantiomeric pairs and their diastereopurities in solution. Detailed photophysical and chiroptical characterization studies reveal that the helicates not only exhibit intense circularly polarized luminescence (CPL) with |g lum | values reaching 0.10, but also show a high luminescence quantum yield of 34%. This study effectively combines the helical chirality of the helicates with the excellent sensitization ability of the β-diketones, providing an effective strategy for the syntheses of chiral lanthanide CPL materials.

Chitin deacetylases (CDAs) convert chitin into chitosan, the N-deacetylated form of chitin, which influences the mechanical and permeability properties of structures such as the cuticle and peritrophic matrices. In this article, a new CDA encoding gene, Hacda2, was cloned by reverse transcription-polymerase chain reaction method in Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), with an open reading frame of 1,611 bp. The deduced protein composed of 536 amino acid residues with a signal peptide, a chitin-binding domain, a low-density lipoprotein receptor class A domain, and a polysaccharide deacetylase-like catalytic domain. The highest expression level of Hacda2 was detected in fat body among tissues tested in the fifth-instar larvae using real-time quantitative polymerase chain reaction method. Feeding of Bacillus thuringiensis (Bt) (Bacillales: Bacillaceae) diet changed the expression level of Hacda1, Hacda2, Hacda5a, and Hacda5b significantly and differentially in the third-instar larvae. Hacda5a and Hacda5b expression were initially down-regulated and then up-regulated, whereas, the expression level of Hacda1 and Hacda2 was suppressed constantly postfeeding on Bt diet. These results suggested that HaCDAs may be involved in the response of H. armigera larvae to Bt and may be helpful to elucidate the roles of HaCDAs in the action of Bt cry toxin. The potential of HaCDAs to be used as synergists of Bt insecticidal protein needs to be further tested., (© The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.)