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1.
Guo-Yu Li Ya-Xin Zheng Fu-Zhou Sun Jian Huang Meng-Meng Lou Jing-Kai Gu Jin-Hui Wang 《International journal of molecular sciences》2015,16(9):22190-22204
This study aimed at investigating the possible mechanisms of hepatic protective activity of Cichorium intybus L. (chicory) in acute liver injury. Pathological observation, reactive oxygen species (ROS) detection and measurements of biochemical indexes on mouse models proved hepatic protective effect of Cichorium intybus L. Identification of active compounds in Cichorium intybus L. was executed through several methods including ultra performance liquid chromatography/time of flight mass spectrometry (UPLC-TOF-MS). Similarity ensemble approach (SEA) docking, molecular modeling, molecular docking, and molecular dynamics (MD) simulation were applied in this study to explore possible mechanisms of the hepato-protective potential of Cichorium intybus L. We then analyzed the chemical composition of Cichorium intybus L., and found their key targets. Furthermore, in vitro cytological examination and western blot were used for validating the efficacy of the selected compounds. In silico analysis and western blot together demonstrated that selected compound 10 in Cichorium intybus L. targeted Akt-1 in hepatocytes. Besides, compound 13 targeted both caspase-1 and Akt-1. These small compounds may ameliorate liver injury by acting on their targets, which are related to apoptosis or autophagy. The conclusions above may shed light on the complex molecular mechanisms of Cichorium intybus L. acting on hepatocytes and ameliorating liver injury. 相似文献
2.
J. Thomas BRENNA 《粮油食品科技》2022,30(3):7-15
人体大脑和身体的发育,需要从食物中摄取均衡的营养物质。人类大脑是区分人类和其他动物的特征。食物中的必需脂肪酸是机体组织结构和功能的必要组成部分。Omega-6(O6)亚油酸(LA6)是皮肤组织的组成成分,且是炎症、血栓形成、免疫和其他信号分子的前体;Omega-3(O3)α-亚麻酸(ALA3),特别是其长链代谢产物——二十二碳六烯酸(DHA3),是大脑、视网膜和部分神经组织中的关键组分。从富含LA6脂肪酸(缺乏O3脂肪酸)的植物籽中提取出的廉价而优质油脂,是20世纪的西方国家食品工业生产的主要脂肪来源。在代谢通路中,高浓度的LA6脂肪酸可拮抗O3脂肪酸代谢,造成O3脂肪酸不足,因此,在给怀孕动物的饲料中,只提供富含LA6但缺乏O3脂肪酸的油脂作为唯一的脂肪来源,会导致幼崽大脑发育不良。过去20~30年的研究表明,低含量LA6且含DHA3的油脂可改善大脑的功能。近年来的研究较多集中在营养因素对大脑发育的影响,最新研究数据表明,脂肪酸平衡对营养不良儿童的大脑发育尤为重要。世界卫生组织(WHO)越来越重视大脑的营养健康,通过其下属的食品法典委员会,建议用于治疗严重急性营养不良儿童的即食治疗食品中,使用含有均衡脂肪酸组成/构成的脂肪。同样,脂肪酸均衡对老年人可能也很重要。目前,业界已经有了调整油脂成分的方法,以确保脂肪酸均衡,从而维持人体整个生命周期的大脑健康。 相似文献
3.
大塑性变形制备纳米结构金属 总被引:5,自引:0,他引:5
细化晶粒是改善材料性能的有效手段,传统的压力加工技术(如轧制、挤压、拉拔和锻造等)可以细化晶粒(微米量级)。纳米结构金属由于具有很小的晶粒尺寸(20-500nm)和独特的缺陷结构,从而表现出优异的物理—力学性能。大塑性变形(SPD)具有将铸态粗晶金属的晶粒细化到纳米量级的巨大潜力,近年来已引起人们的极大关注。介绍了4种大塑性变形制备纳米结构金属的方法、原理、变形特点及应用,分析了纳米结构金属的强度和超塑性变形特征,以及当前研究中存在的主要问题,并对大塑性变形技术的应用前景进行了展望。 相似文献
4.
A. M. Waldum 《Building Research & Information》1993,21(1):51-55
The restoration of relatively old masonry buildings, 1870-1920, represents about 119930 flats and offices in the 4-5 largest cities in Norway. Driving rain and a severe climate are the key factors for deterioration. The paper describes a case study at the city campus of the University of Oslo. 相似文献
5.
Vulnerability, scar, and reciprocal-relations models of depressive symptoms and self-esteem were compared among people with severe mental illness (SMI; N=260) participating in a partnership-based intervention study. Assessments were conducted at baseline, midway through the intervention (after 4 months), and at termination (after 9 months). Cross-lagged, structural equation modeling analyses revealed that participants' baseline depressive symptoms predicted a decrease in self-esteem in the first 4 months but not in the subsequent 5 months of participation. Exploratory regression analyses indicated that improved social functioning buffered this deleterious effect of depressive symptoms. These findings, which are consistent with the scar model, highlight the fragile nature of the self and the importance of social functioning in recovery from SMI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Hypnosis has been demonstrated to reduce analogue pain, and studies on the mechanisms of laboratory pain reduction have provided useful applications to clinical populations. Studies showing central nervous system activity during hypnotic procedures offer preliminary information concerning possible physiological mechanisms of hypnotic analgesia. Randomized controlled studies with clinical populations indicate that hypnosis has a reliable and significant impact on acute procedural pain and chronic pain conditions, Methodological issues of this body of research are discussed, as are methods to better integrate hypnosis into comprehensive pain treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
立管系统中严重段塞流的一维瞬态模型 总被引:1,自引:0,他引:1
严重段塞流主要出现在下倾管段、紧接有一上倾管段或立管段的气、液两相混输海底管道中。根据严重段塞流形成的4个阶段,从一维瞬态流体力学方程出发,建立了一个简化的、准平衡态的严重段塞流数学模型,该模型考虑了流体的物性及流动瞬态效应,可对严重段塞长度、段塞周期、流动速度、压力等特性参数的变化进行模拟。与其他瞬态多相流模型相比,本文模型具有数学模型简单、计算效率高的特点。数值模拟结果表明:当管径较小时,无论介质是空气和水,还是空气和油,由本文模型计算得到的段塞周期和压力结果都与实验数据吻合较好;当管径较大时,若介质为空气和水,则本文模型计算结果与OLGA软件模拟结果较接近;若介质为石油和天然气,在模拟工况范围内,除了小气量工况下偏差较大外,本文模型计算结果与OLGA软件模拟结果相比,段塞周期偏差在25%以内,压力偏差在10%以内;此外,用本文模型计算液塞生长阶段时间t1比Saga-tun模型模拟结果更接近实测结果。 相似文献
8.
聚乙二醇修饰的蓖麻毒蛋白A链的免疫原性和在小鼠体内急性毒性研究 总被引:2,自引:0,他引:2
目的研究单甲氧聚乙二醇(mPEG)与蓖麻毒蛋白A链(RA)偶联后RA免疫原性和毒性的改变。方法从天然蓖麻籽中提取纯化的RA,经与含活性马来酰亚胺基团的mPEG反应偶联,得到纯化的mPEG偶联RA。用蛋白质印迹方法比较RA修饰前后的免疫原性,通过测定半数致死量(LD50)比较RA修饰前后的毒性。结果mPEG偶联RA后免疫原性和毒性均明显下降。偶联前RA链的LD50为2.37 mg.kg-1,经mPEG修饰后RA的LD50为6.15mg.kg-1。结论聚乙二醇能遮蔽RA,降低其免疫原性和毒性。 相似文献
9.
10.
Karolina Bukowska-Strakova Joanna Wodek Ewelina Pitera Magdalena Kozakowska Anna Konturek-Ciela Maciej Ciela Monika Goka Witold Nowak Aleksandra Wieczorek Katarzyna Pawiska-Wsikowska Alicja Jzkowicz Maciej Siedlar 《International journal of molecular sciences》2021,22(3)
Whilst the survival rates of childhood acute lymphoblastic leukemia (ALL) have increased remarkably over the last decades, the therapy resistance and toxicity are still the major causes of treatment failure. It was shown that overexpression of heme oxygenase-1 (HO-1) promotes proliferation and chemoresistance of cancer cells. In humans, the HO-1 gene (HMOX1) expression is modulated by two polymorphisms in the promoter region: (GT)n-length polymorphism and single-nucleotide polymorphism (SNP) A(−413)T, with short GT repeat sequences and 413-A variants linked to an increased HO-1 inducibility. We found that the short alleles are significantly more frequent in ALL patients in comparison to the control group, and that their presence may be associated with a higher risk of treatment failure, reflecting the role of HO-1 in chemoresistance. We also observed that the presence of short alleles may predispose to develop chemotherapy-induced neutropenia. In case of SNP, the 413-T variant co-segregated with short or long alleles, while 413-A almost selectively co-segregated with long alleles, hence it is not possible to determine if SNPs are actually of phenotypic significance. Our results suggest that HO-1 can be a potential target to overcome the treatment failure in ALL patients. 相似文献