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101.
Phenethyl isothiocyanate (PEITC), a constituent of many cruciferous vegetables, is well known to have versatile physiological activities, including chemopreventive effects. On the other hand, its anti‐inflammatory effects are poorly reported. Nitric oxide (NO) is associated with a wide variety of inflammatory diseases. In this study, we investigated the effects of PEITC on NO production in LPS‐activated peritoneal macrophages from ICR mice. The signaling pathway of LPS‐induced NO production was examined using neutralizing antibodies [anti‐interferon (IFN)‐γ and anti‐interleukin (IL‐12)] and specific protein kinase inhibitors, as well as others. The activity of PEITC toward NOx production was assessed in mice that received LPS via intraperitoneal administration. The neutralizing antibody of anti‐IFN‐γ, but not anti‐IL‐12, suppressed LPS‐induced NO production by 90%. LY294002, a specific inhibitor of phosphoinositide‐3‐kinase, suppressed Akt and IFN‐γ mRNA expression up‐regulated by LPS, whereas PEITC exhibited a similar inhibition profile. Furthermore, oral administration of PEITC significantly suppressed the serum concentration of NOx in ICR mice. Our results suggest that PEITC suppresses LPS‐induced NO production via inhibition of Akt activation and the resultant decrease in expression of IFN‐γ. This is one of the first reports to demonstrate a marked anti‐inflammatory effect of PEITC following its oral administration.  相似文献   
102.
Nanoscale magnetic beads coated with nerve growth factor (NGF) allow us to accumulate neurons differentiated from mouse ES cells in a selected area of the culture plate surface using a magnet. Neurons with neurite outgrowths within a particular area expressed TrkA and incorporated beads in the soma.  相似文献   
103.
The thermodynamics of partitioning of allyl isothiocyanate (AITC) in oil/air, oil/water, and octanol/water systems were investigated using the van’t Hoff approach with olive and canola oils as model food oils. The partition coefficients were determined by phase ratio variation method at temperatures between 4 and 50 °C. AITC showed much stronger partitioning into oil or octanol phase than into air or water phase because of its strong hydrophobic nature. As temperature increased, the oil/air, oil/water, and octanol/water partition equilibria were shifted toward air, oil, and octanol phases, respectively. These partitioning behaviors are attributed that the air-to-oil transfer of AITC is an entropically unfavorable, enthalpy-driven spontaneous process, whereas both water-to-oil and water-to-octanol transfers are energetically unfavorable, entropy-driven spontaneous processes. Canola oil was found to be more effective as a solvent for AITC than olive oil in oil/air system but less effective in oil/water system.  相似文献   
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In this study, we presented a simple and direct approach for the decoration of graphene oxide (GO) by fluorescent material. In this protocol, the GO functionalized with COCl groups was first prepared by treating with SOCl2. Fluorescein isothiocyanate (FITC), which is a popular fluorescence probe, was then chemically bonded to the surface of GO sheets, resulting in the formation of FITC-coupled GO hybrid. Fluorescence spectrophotometer, Raman spectroscopy, X-ray photoelectron spectrometer, and Fourier transform infrared spectra were used to demonstrate the successful attachment of FITC to the surface of GO sheets. In addition, the method could be extended to further development of graphene-based nanoelectronics.  相似文献   
108.
建立了环糊精-异硫氰酸烯丙酯包合物的定量分析方法,即利用有机溶剂洗涤法测定包合物表面油,有机溶剂浸提-紫外分光光度法测定包合物中的包合油;该方法具有需要样品量少,操作简便,准确度高的优点。  相似文献   
109.
探究辣木异硫氰酸酯-4-[(α-L-rhamnosyloxy) benzyl] Isothiocyanates(MIC-1)抑制3T3-L1脂肪细胞脂质积累的作用及可能的调控机制。体外诱导3T3-L1前脂肪细胞分化为成熟脂肪细胞,用MIC-1干预48 h后检测细胞脂质积累情况,甘油三酯(TG)、甘油(Gly)和游离脂肪酸(FFA)含量;qRT-PCR检测脂代谢相关基因的表达;Western blot法测定腺苷酸活化蛋白激酶(AMPK)蛋白磷酸化水平和氧化物酶体增殖激活受体γ(PPARγ)蛋白表达水平。结果表明,MIC-1对3T3-L1前脂肪细胞存活率无影响;与对照组相比,MIC-1可降低脂肪细胞内脂滴分布及细胞着色程度,降低细胞内TG含量,减少FFA及甘油的溢出。MIC-1处理浓度达4 mol/L时,TG和FFA浓度分别下降64.00%和75.00%。同时,显著下调细胞中PPARγ(46.00%)、硬脂酰辅酶A去饱和酶1(SCD1)(62.00%)的mRNA表达水平;显著上调AMPK蛋白磷酸化水平(64.47%)和下调PPARγ(52.10%)蛋白表达水平。以上结果表明,MIC-1通过促进TG分解和抑制TG的合成,从而抑制脂质积累,其机制可能与AMPK的活化有关。  相似文献   
110.
二苯乙炔基异硫氰酸酯的合成与液晶性质研究   总被引:4,自引:4,他引:0  
通过先偶联后还原的方法合成了3种具有氟取代的二苯乙炔基异硫氰酸酯化合物。液晶性质测试表明,这些材料均具有较高的Δn值,且随着分子中π电子共轭长度增加而变大,最大可达0.576。将这些高Δn液晶化合物溶于商品炔类液晶材料,可提高其响应速度;其中苯基二苯乙炔基异硫氰酸酯对器件响应性能的提升幅度最大。实验结果表明,二苯乙炔基异硫氰酸酯是一种具有高Δn、低旋转黏度的快速液晶材料,在液晶空间光调制器件中具有一定的应用价值。  相似文献   
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