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1.
Heparanase (Hpse) is an endo-β-D-glucuronidase capable of cleaving heparan sulfate side chains. Its upregulated expression is implicated in tumor growth, metastasis and angiogenesis, thus making it an attractive target in cancer therapeutics. Currently, a few small molecule inhibitors have been reported to inhibit Hpse, with promising oral administration and pharmacokinetic (PK) properties. In the present study, a ligand-based pharmacophore model was generated from a dataset of well-known active small molecule Hpse inhibitors which were observed to display favorable PK properties. The compounds from the InterBioScreen database of natural (69,034) and synthetic (195,469) molecules were first filtered for their drug-likeness and the pharmacophore model was used to screen the drug-like database. The compounds acquired from screening were subjected to molecular docking with Heparanase, where two molecules used in pharmacophore generation were used as reference. From the docking analysis, 33 compounds displayed higher docking scores than the reference and favorable interactions with the catalytic residues. Complex interactions were further evaluated by molecular dynamics simulations to assess their stability over a period of 50 ns. Furthermore, the binding free energies of the 33 compounds revealed 2 natural and 2 synthetic compounds, with better binding affinities than reference molecules, and were, therefore, deemed as hits. The hit compounds presented from this in silico investigation could act as potent Heparanase inhibitors and further serve as lead scaffolds to develop compounds targeting Heparanase upregulation in cancer.  相似文献   
2.
Catalysis Letters - We converted agro-waste Custard Apple Peels (CAP) to ash via thermal treatment, on which Pd(OAc)2 was immobilized easily that produced a low-cost, highly efficient Pd/CAP-ash...  相似文献   
3.
蒋宇佳  于晓强  包明 《精细化工》2021,38(10):2150-2153,2160
二酯类化合物广泛应用于有机中间体、药物、增塑剂、香料等领域,开发其绿色、高效的合成新方法具有重要意义.报道了以二元羧酸(或二羧酸酐)和脂肪醇为原料,以深共融溶剂(DESs)为催化剂催化合成二酯类化合物.以n(氯化胆碱):n(对甲苯磺酸)=1:2为催化剂,产率最高可达95%,并且DESs使用8次后产率仍保持在88%以上.运用1HNMR和13CNMR对产物进行了结构表征.该方法具有操作简单、产率高、易分离和催化剂可循环使用等优点.  相似文献   
4.
建立了层叠流道的三维模型和有限元网格模型,根据流变测试数据,采用Polymat对物料的黏度模型参数进行拟合,并利用Polyflow软件对聚丙烯腈(PAN)凝胶在层叠流道内的三维等温流动过程进行了数值模拟分析。研究发现,当入口流量增大时,层叠流道出口速度的不均匀性增加;沿流动方向流道内压力逐渐降低,并在出口处降低至同一最低值;流道进出口压力差与入口流量大小具有正相关性;在流道的中心截面上剪切速率分布均匀,波动较小。  相似文献   
5.
良好的负荷预测模型能够精准且快速地计算预测值,有利于合理地规划分配电能,提升电网运行稳定性.基于MATLAB搭建灰色Elman网络电力负荷预测模型,参考安徽省淮南市"十三五"能源规划[1],以对淮南市进行中长期电力负荷预测为例,同时设置基于MATLAB搭建的Elman网络和灰色理论中的GM(1,1)模型为对照组进行对比仿真实验.提出灰色Elman网络相比对照组具有更高的运算精度,灰色Elman网络对比Elman网络有更好的训练效果.  相似文献   
6.
运用八段锦进行女大学生篮球教学后疲劳恢复,并与传统恢复手段拉伸运动进行比较实验,探索快速消除运动性疲劳的方法.研究结果显示:女大学生运用八段锦进行篮球教学后的疲劳恢复,其心率恢复明显的优于传统拉伸运动;学生的主观感觉疲劳恢复程度也明显的优于传统拉伸运动.结果表明,八段锦能够有效促进女大学生生理和心理疲劳的恢复.  相似文献   
7.
Background: Recently, it was reported that leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4, also called GPR48) is another receptor for RANKL and was shown to compete with RANK to bind RANKL and suppress canonical RANK signaling during osteoclast differentiation. The critical role of the protein triad RANK–RANKL in osteoclastogenesis has made their binding an important target for the development of drugs against osteoporosis. In this study, point-mutations were introduced in the RANKL protein based on the crystal structure of the RANKL complex and its counterpart receptor RANK, and we investigated whether LGR4 signaling in the absence of the RANK signal could lead to the inhibition of osteoclastogenesis.; Methods: The effects of point-mutated RANKL (mRANKL-MT) on osteoclastogenesis were assessed by tartrate-resistant acid phosphatase (TRAP), resorption pit formation, quantitative real-time polymerase chain reaction (qPCR), western blot, NFATc1 nuclear translocation, micro-CT and histomorphological assay in wild type RANKL (mRANKL-WT)-induced in vitro and in vivo experimental mice model. Results: As a proof of concept, treatment with the mutant RANKL led to the stimulation of GSK-3β phosphorylation, as well as the inhibition of NFATc1 translocation, mRNA expression of TRAP and OSCAR, TRAP activity, and bone resorption, in RANKL-induced mouse models; and Conclusions: The results of our study demonstrate that the mutant RANKL can be used as a therapeutic agent for osteoporosis by inhibiting RANKL-induced osteoclastogenesis via comparative inhibition of RANKL. Moreover, the mutant RANKL was found to lack the toxic side effects of most osteoporosis treatments.  相似文献   
8.
针对PVC企业电石车间存在的粉尘污染严重、人工操作安全隐患大等问题,江苏中吴环境工程设计研究有限公司开发了电石汽车卸料、破碎、除尘、输送一体化智能系统(即中吴天玺系统),对该系统的工艺流程、系统组成、占地空间、经济效益和社会效益簣方面进行了介绍。  相似文献   
9.
The Ag-Pd internal electrode of multilayer piezoelectric ceramics needs to be sintered below 1000°C, and lead wires and components need to be welded with lead-free solder at 260°C. PNN–PMW–PZT–xSr piezoelectric ceramics with high Curie temperature (Tc > 260°C) were synthesized at a low sintering temperature (960°C) to meet the requirements of multilayer piezoelectric devices. The relationship between structures (phase, domain, and microstructures) and electrical properties (piezo/ferroelectric properties, and dielectric relaxation) in the Sr2+ substituted ceramics was investigated. Rietveld refinement and Raman spectra show that Sr2+ substitution can cause the phase change and increase the force constant of [BO6] octahedron. The piezoelectric response increases with increasing the content of the tetragonal phase (CTP) in the rhombohedral-tetragonal (R-T) coexisted ceramics. The ceramics with 0.6 mol% Sr2+ substitution have minimum activation energy for domain wall movement (Ea) of 0.0362 eV which favors the formation of nanometer-sized domains, and possess excellent electrical properties (d33 = 623 pC/N, d33* =783 pm/V, Tc =295°C). The higher the CTP, the lower the Ea. The lower Ea favors the rotation of polarization direction and extension, and is beneficial to the generation of the nanometer-size domains, resulting in high piezoelectric properties.  相似文献   
10.
洪礼武 《大氮肥》2021,44(2):124-126
在传统检测手段无法满足越来越趋向大型化、超大型化的塔器整体两侧直线度的过程检测和控制保障背景下,打破传统思维,大胆创新检测手段,自行设计开发出超大型塔器整体两侧直线度检测整套技术,充分解决超大型塔器整体两侧直线度的检测难题.  相似文献   
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