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71.
Compelling evidence has indicated the vital role of lysine-specific demethylase 4 A (KDM4A), hypoxia-inducible factor-1α (HIF1α) and the mechanistic target of rapamycin (mTOR) signaling pathway in nasopharyngeal carcinoma (NPC). Therefore, we aimed to investigate whether KDM4A affects NPC progression by regulating the HIF1α/DDIT4/mTOR signaling pathway. First, NPC and adjacent tissue samples were collected, and KDM4A protein expression was examined by immunohistochemistry. Then, the interactions among KDM4A, HIF1α and DDIT4 were assessed. Gain- and loss-of-function approaches were used to alter KDM4A, HIF1α and DDIT4 expression in NPC cells. The mechanism of KDM4A in NPC was evaluated both in vivo and in vitro via RT-qPCR, Western blot analysis, MTT assay, Transwell assay, flow cytometry and tumor formation experiments. KDM4A, HIF1α, and DDIT4 were highly expressed in NPC tissues and cells. Mechanistically, KDM4A inhibited the enrichment of histone H3 lysine 9 trimethylation (H3K9me3) in the HIF1α promoter region and thus inhibited the methylation of HIF1α to promote HIF1α expression, thus upregulating DDIT4 and activating the mTOR signaling pathway. Overexpression of KDM4A, HIF1α, or DDIT4 or activation of the mTOR signaling pathway promoted SUNE1 cell proliferation, migration, and invasion but inhibited apoptosis. KDM4A silencing blocked the mTOR signaling pathway by inhibiting the HIF1α/DDIT4 axis to inhibit the growth of SUNE1 cells in vivo. Collectively, KDM4A silencing could inhibit NPC progression by blocking the activation of the HIF1α/DDIT4/mTOR signaling pathway by increasing H3K9me3, highlighting a promising therapeutic target for NPC.Subject terms: Oncogenes, Cancer  相似文献   
72.
In this paper we consider the job shop scheduling problem under a discrete non-renewable resource constraint. We assume that jobs have arbitrary processing times and resource requirements and there is a unit supply of the resource at each time period. We develop an approximation algorithm for this problem and empirically test its effectiveness in finding the minimum makespan schedules.  相似文献   
73.
Journal of Radioanalytical and Nuclear Chemistry - Here we report the synthesis of boron nitride nanotubes (BNNTs) via a chemical vapor deposition method, as potential agents for boron neutron...  相似文献   
74.
A biosensing system based on α-glucosidase (AG) activity was developed by using bismuth film modified glassy carbon electrode (BiFE). AG enzyme was immobilized on the BiFE by means of gelatin membrane and the activity was measured by the following of liberated 4-nitrophenol from the 4-nitrophenyl-α-d-glucopyranoside (PNPGP) which is the synthetic substrate of the enzyme at the working potential of −950 mV. The proposed system was used as an AG based biosensing system. Experimental data showed that the response current of 4-nitrophenol obtained at the BiFE was linear in concentration range between 0.033 and 0.33 mM of PNPGP. Before examining the analytical characteristics, pH optimization of the AG-biosensor was also performed. Furthermore, the proposed method was applied to analyze two different AG inhibitors (Amaryl and Acorbose) which are important in Noninsulin-dependent diabetes mellitus (NIDDM).  相似文献   
75.
In this study, a bismuth film was used as a sensing platform for immunoreaction assay which includes the interactions between IgE and anti‐IgE molecules. For preparing this assay, IgE was deposited on a carbon paste electrode via bismuth(III) cations without using any membrane or functional reagent. The immobilized reagents and interaction of anti‐IgE on this formation were monitored by using atomic force microscopy technique and electrochemical impedance spectroscopy. Then some experimental parameters like the effect of IgE amount and the IgE–anti‐IgE interaction time were optimized. Under the optimal experimental conditions, the binding of anti‐IgE was also examined by following current decrease in differential pulse voltammograms of neutral red.  相似文献   
76.
In the title compound, poly[[triaqua{μ4‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}{μ2‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}barium(II)] monohydrate], {[Ba(C9H8N3O6S3)2(H2O)3]·H2O}n, each BaII atom is nine‐coordinated by six O atoms from carboxylate groups of four different 2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetate ligands and three O atoms from water molecules. The triazine ligand is partially deprotonated, as verified by intermolecular hydrogen‐bonding parameters, and adopts μ2‐η11 and μ4‐η112 coordination modes to connect the BaII centres, forming a novel double‐layered structure. Topological analysis indicates that the whole structure is a novel (4,6)‐connected net, considering the ligands and BaII centres as four‐ and six‐connected nodes, respectively.  相似文献   
77.
In this study we derive the Gelfand-Levitan-Marchenko type main integral equation of the inverse problem for the boundary value problem $L$ and prove the uniquely solvability of the main integral equation. Further, we give the solution of the inverse problem by the spectral data and by two spectrum.  相似文献   
78.
Flooded soil samples were collected in the typical area of the Yangtze Delta Region;fractions of heavy metals in flooded and air dried samples were measured with BCR sequential extraction method and atomic absorption spectrometry.In flooded soils, fractions of heavy metals increased in the order of acid soluble < oxidizable < reducible < residual.The acid soluble and reducible fractions significantly decreased but residual fraction significantly increased when the samples were air dried.The data obtained from air dried soil samples could not accurately represent the speciation of heavy metals in flooded field conditions.  相似文献   
79.
A catalytic method was developed to synthesize substituted phenols from the corresponding aryl bromides and chlorides under mild conditions (yields = 34–92%). 4-Methoxylbenzyl alcohol was used as water surrogate and CuI/3,4,7,8-tetramethyl-1,10-phenanthroline was used as catalyst to achieve the C–O cross-coupling.  相似文献   
80.
Thioxanthone (TX) and its derivatives, which are widely used as photoinitiators in UV curing technology, hold promising research interest in biological applications. In particular, the use of TXs as anticancer agent has recently been manifested as an outstanding additional property of this class of molecules. Incorporation of TX molecules into specially designed polymers widens their practical use in such applications. In this study, two water‐soluble, biocompatible, and stable polymers, namely poly(vinyl alcohol) and poly(ethylene glycol), possessing TX moieties at the side chains and chain ends, respectively, are prepared and used as anticancer and radiotherapy agents. The findings confirm that both polymers are potential candidates for therapeutic agents as they possess useful features including water‐solubility, radiosensitizer effect, and anticancer activity in a polymeric scaffold.

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