Qualitative Analysis of the Helical Electronic Energy of Inherently Chiral Calix[4]arenes: An Approach to Effectively Assign Their Absolute Configuration

For all microhelices on aromatic rings of inherently chiral calix[4]arene, an expression was derived from one approximation and one hypothesis on the basis of the electron-on-a-helix model of Tinoco and Woody as follows: , where µ = 1 for the right-handed microhelix and µ = −1 for the left-handed microhelix; and H and K are constant and greater than zero. The expression correlates microhelical electronic energy (E) with the atom polarizability difference (Δα) on both microhelix ends, which intuitively and clearly shows the impact of helical substituent polarizability on helical electronic energy. The case analysis almost entirely proves that the qualitative analysis of the helical electronic energy of inherently chiral Calix[4]arenes with the expression is scientific and can be used to effectively assign their absolute configuration.     

乙型脑炎灭活疫苗Vero细胞适应毒种的研究

将乙脑P3株鼠脑毒种在Vero细胞中适应性传代，当传至10代时，毒种的CPE和感染性虽无明显变化，但其免疫原性却明显减弱，因此，用在Vero细胞中传递1至2代的几株建立毒种库（P3V1和P3V2），其涵度分别为7．71和78210gpfu／ml。在毒种中加入以山梨醇为主要成分的稳定剂后，4～S℃保存30天，－30℃1年，－60℃2年，滴度降低约0．51ogpfu／ml，在生产中使用效果良好。     

Rapid and Efficient Functionalized Ionic Liquid-Catalyzed Aldol Condensation Reactions Associated with Microwave Irradiation

Five quaternary ammonium ionic liquid (IL) and two tetrabutylphosphonium ILs were prepared and characterized. An environmentally benign and convenient functionalized ionic liquid catalytic system was thus explored in the aldol condensation reactions of aromatic aldehydes with acetone. The aldol reactions proceeded more efficiently through microwave-assisted heating than through conventional thermal heating. The yield of products obtained under microwave heating for 30 min was approximately 90%, and the ILs can be recovered and reused at least five times without apparent loss of activity. In addition, this catalytic system can be successfully extended to the Henry reactions.     

Effect of In/Al ratios on structural and optical properties of InAlN films grown on Si(100) by RF-MOMBE

In _x Al_1-x N films were deposited on Si(100) substrate using metal-organic molecular beam epitaxy. We investigated the effect of the trimethylindium/trimethylaluminum (TMIn/TMAl) flow ratios on the structural, morphological, and optical properties of In _x Al_1-x N films. Surface morphologies and microstructure of the In _x Al_1-x N films were measured by atomic force microscopy, scanning electron microscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), respectively. Optical properties of all films were evaluated using an ultraviolet/visible/infrared (UV/Vis/IR) reflection spectrophotometer. XRD and TEM results indicated that In _x Al_1-x N films were preferentially oriented in the c-axis direction. Besides, the growth rates of In _x Al_1-x N films were measured at around 0.6 μm/h in average. Reflection spectrum shows that the optical absorption of the In _x Al_1-x N films redshifts with an increase in the In composition.     

Characterization and density control of GaN nanodots on Si (111) by droplet epitaxy using plasma-assisted molecular beam epitaxy

In this report, self-organized GaN nanodots have been grown on Si (111) by droplet epitaxy method, and their density can be controlled from 1.1 × 10¹⁰ to 1.1 × 10¹¹ cm^-2 by various growth parameters, such as substrate temperatures for Ga droplet formation, the pre-nitridation treatment of Si substrate, the nitridation duration for GaN crystallization, and in situ annealing after GaN formation. Based on the characterization of in situ RHEED, we can observe the surface condition of Si and the formation of GaN nanodots on Si. The surface nitridaiton treatment at 600°C provides a-SiNx layer which makes higher density of GaN nanodots. Crystal GaN nanodots can be observed by the HRTEM. The surface composition of GaN nanodots can be analyzed by SPEM and μ-XPS with a synchrotron x-ray source. We can find GaN nanodots form by droplet epitaxy and then in situ annealing make higher-degree nitridation of GaN nanodots.     

Apigenin-7-Glycoside Prevents LPS-Induced Acute Lung Injury via Downregulation of Oxidative Enzyme Expression and Protein Activation through Inhibition of MAPK Phosphorylation

Apigenin-7-glycoside (AP7Glu) with multiple biological activities is a flavonoid that is currently prescribed to treat inflammatory diseases such as upper respiratory infections. Recently, several studies have shown that its anti-inflammatory activities have been strongly linked to the inhibition of secretion of pro-inflammatory proteins, such as inducible nitric oxide synthase (iNOs) and cyclooxygenase-2 (COX-2) induced through phosphorylation nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK) pathways. Additionally, inflammation, which can decrease the activities of antioxidative enzymes (AOEs) is also observed in these studies. At the same time, flavonoids are reported to promote the activities of heme oxygenase-1 (HO-1) decreased by LPS. The purpose of this study was to assess these theories in a series of experiments on the suppressive effects of AP7Glu based on LPS-induced nitric oxide production in RAW264.7 macrophages in vitro and acute lung injury in mice in vivo. After six hours of lipopolysaccharide (LPS) stimulation, pulmonary pathological, myeloperoxidase (MPO) activity, total polymorphonuclear leukocytes (PMN) cells, cytokines in bronchoalveolar lavage fluid (BALF) and AOEs, are all affected and changed. Meanwhile, our data revealed that AP7Glu not only did significantly inhibit the LPS-enhanced inflammatory activity in lung, but also exhibited anti-inflammatory effect through the MAPK and inhibitor NF-κB (IκB) pathways.     

The Effects of Marine Carbohydrates and Glycosylated Compounds on Human Health

Marine organisms have been recognized as a valuable source of bioactive compounds with industrial and nutraceutical potential. Recently, marine-derived carbohydrates, including polysaccharides and low molecular weight glycosylated oligosaccharides, have attracted much attention because of their numerous health benefits. Moreover, several studies have reported that marine carbohydrates exhibit various biological activities, including antioxidant, anti-infection, anticoagulant, anti-inflammatory, and anti-diabetic effects. The present review discusses the potential industrial applications of bioactive marine carbohydrates for health maintenance and disease prevention. Furthermore, the use of marine carbohydrates in food, cosmetics, agriculture, and environmental protection is discussed.     

New Coumarin Derivatives and Other Constituents from the Stem Bark of Zanthoxylum avicennae: Effects on Neutrophil Pro-Inflammatory Responses

Three new coumarin derivatives, 8-formylalloxanthoxyletin (1), avicennone (2), and (Z)-avicennone (3), have been isolated from the stem bark of Zanthoxylum avicennae (Z. avicennae), together with 15 known compounds (4–18). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 1, 4, 9, 12, and 15 exhibited inhibition (half maximal inhibitory concentration (IC₅₀) values ≤7.65 µg/mL) of superoxide anion generation by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (fMLP/CB). Compounds 1, 2, 4, 8 and 9 inhibited fMLP/CB-induced elastase release with IC₅₀ values ≤8.17 µg/mL. This investigation reveals bioactive isolates (especially 1, 2, 4, 8, 9, 12 and 15) could be further developed as potential candidates for the treatment or prevention of various inflammatory diseases.     

Cu-B2O3/SiO2, an effective catalyst for synthesis of fatty alcohol from hydrogenolysis of fatty acid esters

This work demonstrates that Cu- B₂O₃/SiO₂ is an effective catalyst for synthesis of fatty alcohols from hydrogenolysis of fatty acid esters. Boron oxide not only acts as a textural promoter to increase the dispersion of copper, but also as a structural promoter to decrease the activation energy of hydrogenolysis by 10 kJ/mol. The optimum loading of boron oxide doped is around 6.4 wt%. This chromium-free copper catalyst is seven times as active as the commercial copper chromite (Engelhard Cu-1234E) in the hydrogenolysis of methyl esters at 240°C, 110 bar. Cu- B₂O₃(6.4%)/SiO₂ is a promising catalyst for lower pressure (<150 bar) hydrogenolysis processes. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis of cocoa butter equivalent by lipase-catalyzed interesterification in supercritical carbon dioxide

With supercritical carbon dixoide as a reaction medium, the syntheses of cocoa butter equivalent by interesterification with various lipases were investigated. The study showed that among those five lipases tested, lipase IM-20 from Mucor miehei was the most effective and specific in synthesizing this cocoa butter equivalent product by interesterification. The yields of cocoa butter equivalent are affected by pressure, substrate oil composition, solubility and co-solvent. The best reaction conditions were: reaction pressure at 1500 psi, triglyceride with high content of POP (P, palmitate; O, oleate) and POO, reaction medium with 5.0% water, and reaction temperature at 50°C. The major component of cocoa butter, POS (S, stearate), can be increased by 6.0% by adding a small amount of carbon dioxide. The yield and melting point of the purified cocoa butter equivalent are 53.0% and 34.3°C, respectively.