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91.
Poya Kavianpour Madeleine C. M. Gemmell Dr. Jan U. Kahlert Prof. Louis M. Rendina 《Chembiochem : a European journal of chemical biology》2020,21(19):2786-2791
Histone deacetylase enzymes (HDACs) are responsible for the global silencing of tumour-suppressor genes. Treatment with a histone deacetylase inhibitor (HDACi) can reverse this process and restore normal cell function. Herein, we report a small series of boron-based (boronic acid, boronate ester and closo-1,2-carborane) HDAC2 inhibitors with IC50 values in the nanomolar range. The boronate ester 4 b was the most potent compound assessed in this study (IC50=40.6±1.5 nM), followed closely by the 1,2-closo-carborane (IC50=42.9±1.5 nM). Compound 4 b exceeds the potency of the related gold-standard HDAC pan-inhibitor vorinostat ( 1 ) toward this particular HDAC isoform. 相似文献
92.
Hans-Peter Martin Bing Feng Alexander Michaelis 《International Journal of Applied Ceramic Technology》2020,17(2):407-412
Boron carbide and Tantalum boride composites were prepared by pressureless sintering of B4C with addition of TaC powder. The effect of TaC addition on the sinterability of boron carbide was studied. High densified ceramic with a relative density of 98.7% was obtained at sintering temperature of 2250°C. The composition and the microstructure of the dense composites are characterized by means of x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDX). The studies show that the composites contain boron carbide, TaB2, and carbon phases with a homogeneous structure. In addition, the correlation between the composition and the electrical conductivity was investigated. The electrical conductivity of the composite increased with increasing addition of TaC, and a change in conduction behavior from semiconducting to metallic was observed. High hardness value of 28.49 ± 1.33 GPa was obtained by the sample with 30 wt% TaC addition. 相似文献
93.
Dr. Marlon R. Lutz Jr. Sebastian Flieger Andre Colorina John Wozny Prof. Dr. Narayan S. Hosmane Prof. Dr. Daniel P. Becker 《ChemMedChem》2020,15(20):1897-1908
Based on the previously reported potent and selective sulfone hydroxamate inhibitors SC-76276, SC-78080 (SD-2590), and SC-77964, potent MMP inhibitors have been designed and synthesized to append a boron-rich carborane cluster by employing click chemistry to target tumor cells that are known to upregulate gelatinases. Docking against MMP-2 suggests binding involving the hydroxamate zinc-binding group, key H-bonds by the sulfone moiety with the peptide backbone residues Leu82 and Leu83, and a hydrophobic interaction with the deep P1’ pocket. The more potent of the two triazole regioisomers exhibits an IC50 of 3.7 nM versus MMP-2 and IC50 of 46 nM versus MMP-9. 相似文献
94.
Qiaoran Zhang Mengmeng Zhang Huili Shi Zhiwei Li Laigui Yu Xiaohong Li Zhijun Zhang Zhishen Wu 《应用聚合物科学杂志》2020,137(17):48609
95.
电子回旋共振(ECR)质子源具有可给流强高、亮度高、可靠性高、使用频率高、易维护、小型化等优点,因而被硼中子俘获治疗(BNCT)装置的直线加速器所采用。本文利用CST软件对2.45 GHz ECR质子源进行优化设计。优化后ECR质子源的等离子体发生器腔体的尺寸为101.12 mm×45.00 mm,给出了脊波导耦合器的最优尺寸参数,使等离子体发生器腔体内电场强度提高为普通波导的4.5倍。通过Opera-3D对ECR质子源的引出电极结构进行了仿真计算,并给出了优化参数。另外,初步设计了质子源的线圈磁铁系统,优化了磁场分布。本文结果为质子源的研制提供了数据。 相似文献
96.
Naoya Miyahara Shuhei Miwa Naoki Horiguchi Isamu Sato Osaka Masahiko 《Journal of Nuclear Science and Technology》2019,56(2):228-240
In order to improve LWR source term under severe accident conditions, the first version of a fission product chemistry database named ‘ECUME’ was developed. The ECUME is intended to include several datasets of major chemical reactions and their effective kinetic constants for representative severe accident sequences. It is expected that the ECUME can serve as a fundamental basis from which fission product chemical models can be elaborated for use in the severe accident analysis codes. The implemented chemical reactions in the first version were those for representative gas species in Cs-I-B-Mo-O-H system from 300 to 3000 K. The chemical reaction kinetic constants were evaluated from either literature data or calculated values using ab-initio calculations. The sample chemical reaction calculation using the presently constructed dataset showed meaningful kinetics effects at 1000 K. Comparison of the chemical equilibrium compositions by using the dataset with those by chemical equilibrium calculations has shown rather good consistency for the representative Cs-I-B-Mo-O-H species. From these results, it was concluded that the present dataset should be useful to evaluate fission product chemistry in Cs-I-B-Mo-O-H system under LWR severe accident conditions, where kinetics effects should be considered. 相似文献
97.
In this study, changes of intramuscular phospholipids and free fatty acids were tracked during the processing of Nanjing dry-cured duck. Phospholipids were identified and quantified by high performance liquid chromatography combined with UV and evaporative light scattering detectors. The types and quantities of free fatty acids and fatty acids derived from phospholipids were analyzed by capillary gas chromatography. The results showed that raw duck meat had high quantities of phosphatidylethanolamine, and phosphatidylcholine (37.95% and 54.07% of total phospholipids, respectively), which contained high percentages of polysaturated fatty acids. The percentages of total phospholipids, phosphatidylethanolamine, and phosphatidylcholine decreased during processing, with a concomitant increase in quantities of free fatty acids. The lipolysis of phospholipids, especially phosphatidylethanolamine is the main contributor to the increase of free fatty acids. 相似文献
98.
通过对原料、触媒及合成工艺的研究,采用国产DS-029B型六面顶压机在4.2—5.3GPa,1350。1470℃的范围内,从hBN-单质触媒体系中合成出近乎完美的黑色八面体和截角八面体立方氮化硼单晶体。确定了该种形态的CBN晶体的生长区域。CBN晶体的尺寸在100—400μm,峰值粒度为125—150μm。对所得的晶体进行考察,发现这种CBN晶体结晶形貌发育比较完整、棱角尖锐、晶粒饱满,并且有较高的抗压强度。上述结果表明所用的单质触媒具有使CBN晶体均匀生长的能力,是一种合成CBN晶体的有效触媒,该种CBN晶体具有较好的破碎强度。 相似文献
99.
HY which is loaded with SbF5, BCl3, or BF3 at low coverages, one metal halide molecule per Brønsted acid site, is shown to be active in the isomerization and cracking of n-hexane and n-butane at room temperature. In contrast, NaY with the same metal halide loading shows greatly reduced activity under identical reaction conditions. The cracking reaction was repeated with DY in place of HY, demonstrating deuterium incorporation into the hexane isomer and light alkane products through interaction with the Brønsted site. Flow reactor studies demonstrate that the conversion is not constant as a function of time on stream, going through an induction period, reaching a maximum, at around 400 s, and then decaying to ~1% after 1 h. 相似文献
100.