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991.
Feng‐Yao Tang Yu‐Ching Su Nai‐Chia Chen Hui‐Shan Hsieh Kaun‐Suei Chen 《Molecular nutrition & food research》2008,52(6):683-691
Metastasis is the primary cause of death from breast cancer. Cell migration and invasion play important roles in neoplastic metastasis. The insulin‐like growth factor (IGF‐1) stimulates cell migration through activation of PI‐3K/Akt signaling pathway. IGF‐1 induces the tumorigenicity of many types of cancer cells and is critical for metastatic cell spread in estrogen receptor (ER)‐negative breast‐cancer cells. Matrix metalloproteinase‐2 (MMP‐2) is a key enzyme in the degradation of extracellular matrices and its expression has been dysregulated in breast cancer invasion and metastasis. Resveratrol exhibited potential anticarcinogenic activities in several studies. However, the inhibitory effects of resveratrol on the expression of MMP‐2, migration and invasion of breast‐cancer cell have not been demonstrated yet. In the present study, we investigated the anti‐invasive mechanism of resveratrol in human breast cancer MDA‐MB 435cells. Here, we showed that IGF‐1 is a potent stimulant of the migration of ER‐negative human breast‐cancer cells. Resveratrol could inhibit IGF‐1‐mediated cell migration of MDA‐MB 435 in vitro. The inhibitory effect of resveratrol was mediated in part through the suppression of the activation of PI‐3K/Akt signaling pathway. Furthermore, IGF‐1‐mediated expression of MMP‐2 was significantly inhibited by resveratrol in concomitance with alteration of cell invasion. 相似文献
992.
Crude extract and solvent-partitioned fraction of Glehnia littoralis were found to possess different anti-proliferative effects against AGS, HT1080 and U937 human cancer cells. The crude extracts and solvent fractions dose-dependently inhibited cell proliferation. Especially, n-hexane and 85% aqueous MeOH fractions exhibited comparatively higher anti-proliferative effects and reduced expressions of Bcl-2, COX-2 and iNOS genes. Systematic separation of all solvent fractions by chromatographic methods led to the isolation of three glucopyranosides, four furanocoumarins and two polyacetylenic alcohols. All the nine compounds were evaluated for their inhibitory effects against both proliferation of human cancer cells and expressions of MMP-2 and -9 in HT1080 cells. Two polyacetylenic alcohols exerted the highest inhibitory activity against both human cancer cell lines, and MMP-2 and -9. These results suggest that G. littoralis may possibly be used as a valuable chemopreventive agent or food supplement for reducing cancer risk. 相似文献
993.
994.
Jing-Ying Xu Yuan-Yuan Su Jin-Sheng Cheng Ruili Liu Guo-Tong Xu Qing-Nuan Li 《Carbon》2010,48(5):1388-1396
An important biologically-relevant property of fullerenol is its ability to quench free radicals. Carbon tetrachloride (CCl4)-induced hepatotoxicity and nephrotoxicity model was used to investigate the possible mechanisms of fullerenol protection in Sprague-Dawley rats in this study. Rats were administrated with fullerenol (0, 1, 1.5 and 5 mg/kg d) by intravenous or intraperitoneal injection for 3 days before CCl4 challenge, 24 h following the CCl4 challenge, all the rats were assessed using serum and tissue homogenates biomarkers as well as the pathological evaluation. All results showed that CCl4 caused significant increasing serum activity of alanine aminotransferase and aspartate aminotransferase, as well as the concentration of blood urea nitrogen and creatinine. Malondialdehyde level was also increased significantly, whereas the ratio of reduced glutathione to oxidized glutathione was decreased in tissue homogenates. The pathological evaluation indicated the liver and kidney were damaged by CCl4. Fullerenol-pretreatment alleviated biomarker changes as well as histological changes significantly, and fullerenol-pretreatment alone can increase the ratio of reduced glutathione to oxidized glutathione, which indicated fullerenol could protect tissues against CCl4-induced oxidative stress by improving the antioxidant ability. 相似文献
995.
996.
叙述了阻燃聚氨酯软质泡沫塑料中氯含量的测定方法:在助燃剂存在下,氧瓶燃烧使聚氨酯软质泡沫塑料中的有机氯转化为HCl,用稀NaOH吸收,使用硫氰酸汞分光光度法测定聚氨酯软质泡沫塑料中阻燃剂的氯含量。该方法简单快捷、精确度高,回收率为99.64%~102.41%。 相似文献
997.
3种海参多糖的分离纯化及其化学组成差异分析 总被引:1,自引:0,他引:1
提取3种海参中的粗多糖,通过Q Sepharose Fast Flow(QFF)阴离子交换柱分离纯化,得到海参硫酸软骨素(SC-CHS)及海参岩藻聚糖硫酸酯(SC-FUC)2个组分,并比较3种海参多糖的化学组成。对粗多糖、SC-CHS及SC-FUC分别采用高效凝胶排阻色谱法、柱前衍生高效液相色谱法及离子色谱法测定各海参多糖的相对分子质量、单糖组成及硫酸根含量。结果表明,随着海参种类的不同,3种海参SC-CHS相对分子质量之间无显著性差异,均为120kDa左右;各海参SC-FUC相对分子质量存在显著性差异,其中以海地瓜SC-FUC的相对分子质量最大。不同海参多糖葡萄糖醛酸(GlcUA)、氨基半乳糖(GalN)、半乳糖(Gal)及岩藻糖(Fuc)的物质的量比存在显著性差异。各海参SC-CHS的硫酸根含量在29%左右,各海参SC-FUC的硫酸根含量在26%左右。 相似文献
998.
为了顺利生产Outlast腈纶混纺针织纱,分析了Outlast腈纶纤维的性能特点,并在纺纱过程中针对性地采取了工艺技术改进措施。通过纺纱前喷洒抗静电剂;清梳工序适当降低各打击梳理机件速度,放大梳理隔距;并条工序采用重加压、大隔距、轻定量工艺原则;粗纱工序选用较小的后区牵伸与较大的罗拉隔距;细纱工序在较大粗纱捻系数的基础上,采用较大的后区隔距、较小的后区牵伸、低速度等工艺;各工序严格控制温湿度,结果成功纺制出棉/Outlast腈纶60/40 18.3 tex混纺针织纱,达到了较好的质量水平。 相似文献
999.
巨大芽孢杆菌L2发酵产物对魔芋软腐病菌的抑菌机制 总被引:1,自引:0,他引:1
目的:探究巨大芽孢杆菌(Bacillus megaterium)L2发酵产物对贮藏期魔芋软腐病菌——胡萝卜软腐欧文氏菌(Erwinia carotovora subsp. carotovora)EC-1的抑菌机制。方法:以巨大芽孢杆菌菌粉为原料提取发酵产物,用常压硅胶柱层析分离得到发酵产物流分LE4-1~LE4-7,经抑菌实验筛选得到对胡萝卜软腐欧文氏菌EC-1有良好抑菌作用的流分,再使用气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)法对其进行成分分析;并通过测定其半数抑制质量浓度(half maximal inhibitory concentration,IC50)、菌液电导率、核酸蛋白泄漏、可溶性总糖质量浓度、菌体总蛋白、菌体磷代谢及胞内活性氧水平对其抑菌机制进行研究。结果:巨大芽孢杆菌L2流分LE4-3对胡萝卜软腐欧文氏菌EC-1有良好抑菌作用,经GC-MS检测其主要成分为苯乙酸乙酯(32.190%(相对含量,后同))、亚油酸乙酯(15.819%)、苯乙酸甲酯(13.793%)等;LE4-3对胡萝卜软腐欧文氏菌EC-1的IC50为(1.06±0.01)mg/mL,并初步推测其作用机制是通过影响细胞膜完整性、损伤细胞结构、抑制细胞蛋白质合成及能量代谢等对胡萝卜软腐欧文氏菌EC-1发挥抑菌作用,因此巨大芽孢杆菌L2流分LE4-3在魔芋抗软腐病贮藏中具有良好的应用前景。 相似文献
1000.
Yunzi Feng Yu Cai Dongxiao Sun-Waterhouse Xiong Fu Guowan Su Mouming Zhao 《Food Analytical Methods》2017,10(4):931-942
A method based on simultaneous distillation extraction (SDE) coupled with gas chromatography–mass spectrometry/olfactometry (GC-MS/O) was developed for the analysis of volatile profiles in soy sauce. Its optimum operating conditions were as follows: 100 mL soy sauce plus 100 mL saturated brine; 2 h extraction using 50 mL dichloromethane. Eighty-eight volatile compounds were identified. Of these, 26 aroma-active compounds were detected by GC-O including 3-(methylthio)propanal, 2-methoxy-4-vinylphenol, 2-methoxyphenol, 2-methylbutanoic acid, 2,3-butanedione, phenylacetaldehyde, 2-ethyl-6-methylpyrazine, 3-methylbutanal, 2-methylbutanal, 3-methyl-1-butanol, and 2-methyl-1-butanol (which occurred at a high odor intensity in both high-salt liquid-state fermentation soy sauce (HLFSS) and low-salt solid-state fermentation soy sauce (LSFSS). SDE analysis of the odorless soy sauce indicated 12 volatiles (mainly Strecker aldehydes and α-dicarbonyl compounds). Thus, the proportions of these compounds (1.94–54.07 %) shown in previous GC-MS results could result from thermal degradation of non-volatile compounds in soy sauce. Especially, the contribution of 3-methylbutanal, 2-methylbutanal, phenylacetaldehyde, 3-(methylthio)propanal, and 2,3-butanedione to the aroma of soy sauce could be overestimated by conventional SDE-GC-O. With a full consideration of such limitations, this study will improve the application of SDE on aroma analysis of complex food matrix. 相似文献