Anionic synthesis of binary random in-chain multi-functionalized poly(styrene/butadiene/isoprene and dimethyl [4-phenylvinyl)-phenyl]silane)(PS-DPESiH,PB-DPESiH,PI-DPESiH) copolymers

The binary random in-chain silyl-hydride multi-functionalized poly(styrene/butadiene/isoprene and dimethyl[4-(1-phenylvinyl) phenyl]silane)(PS-DPESiH,PB-DPESiH,PI-DPESiH) copolymers were successfully synthesized.These functionalized copolymers were prepared in hexane with n-BuLi as the initiator at 50℃for 4 h.The silyl-hydride groups were introduced into polymer backbones quantitatively by living anionic polymerization.The copolymers were determined through ’H NMR,size exclusion chromatography(SEC) and differential scanning calorimetry(DSC) techniques,while the number of silyl-hydride groups was calculated and discussed.     

Production of high-quality agarwood in Aquilaria sinensis trees via whole-tree agarwood-induction technology

We used whole-tree agarwood-induction technology to produce agarwood from Aquilaria sinensis trees within 20 months,and evaluated the quality of this agarwood.The results showed its characteristics were similar to those of high-grade wild agarwood in terms of texture,chemical constituents,essential oil content,and ethanol-soluble extract content,with the lattermost quality far surpassing the requirement of traditional Chinese medicine agarwood,as indicated in Chinese Pharmacopoeia 2010.To the best of our knowledge,this is first study to show that high-quality agarwood can be produced in whole A.sinensis trees via a chemically induced technology.     

基于三维荧光特性的汽油聚类分析

应用三维荧光光谱法研究了90#、93#及97#3种汽油纯样品以及它们的相互掺杂样品的荧光特性。选取激发波长(λex)为330nm,发射波长(λem)在340～500nm间的荧光强度数据,用主成分聚类分析法作了研究。结果表明:所得的荧光数据分为三类,属90#汽油样品的数据为一类,处于第Ⅰ象限中;属97#汽油样品为第二类,处于第Ⅲ象限;属93#汽油样品为第三类,处于第Ⅳ象限。在第Ⅰ及第Ⅳ象限中的荧光数据又分为二类,一类为纯品油样,另一类为混杂油样。因此,根据聚类分析结果可方便地对不同标号的汽油加以区别。而且根据纯品汽油样品与混杂油样品的试验点之间的距离可推测油样中混杂组分量的多少。     

Recognition of myo-inositol 1,4,5-trisphosphate using a fluorescent imidazolium receptor

The first example of an imidazolium-based fluorescent receptor for D-myo-inositol 1,4,5-trisphosphate (IP(3)) is reported in this study. The fluorescent receptor 1 bearing four imidazolium and pyrene groups displayed a large fluorescent quenching effect with myo-IP(3) compared to fluorescent changes with various IP series, pyrophosphate, and ATP.     

Fluorescence-based multiplex protein detection using optically encoded microbeads

Potential utilization of proteins for early detection and diagnosis of various diseases has drawn considerable interest in the development of protein-based multiplex detection techniques. Among the various techniques for high-throughput protein screening, optically-encoded beads combined with fluorescence-based target monitoring have great advantages over the planar array-based multiplexing assays. This review discusses recent developments of analytical methods of screening protein molecules on microbead-based platforms. These include various strategies such as barcoded microbeads, molecular beacon-based techniques, and surface-enhanced Raman scattering-based techniques. Their applications for label-free protein detection are also addressed. Especially, the optically-encoded beads such as multilayer fluorescence beads and SERS-encoded beads are successful for generating a large number of coding.     

6-shogaol-rich extract from ginger up-regulates the antioxidant defense systems in cells and mice

The rhizome of ginger (Zingiber officinale Roscoe) is known to have several bioactive compounds including gingerols and shogaols which possess beneficial health properties such as anti-inflammatory and chemopreventive effects. Based on recent observations that 6-shogaol may have more potent bioactivity than 6-gingerol, we obtained a 6-shogaol-rich extract from ginger and examined its effects on the nuclear factor E2-related factor2 (Nrf2)/antioxidant response element (ARE) pathway in vitro and in vivo. 6-Shogaol-rich extract was produced by extracting ginger powder with 95% ethanol at 80 °C after drying at 80 °C (GEE8080). GEE8080 contained over 6-fold more 6-shogaol compared to the room temperature extract (GEE80RT). In HepG2 cells, GEE8080 displayed much stronger inductions of ARE-reporter gene activity and Nrf2 expression than GEE80RT. GEE8080 stimulated phosphorylations of mitogen-activated protein kinases (MAPKs) such as ERK, JNK, and p38. Moreover, the GEE8080-induced expressions of Nrf2 and HO-1 were attenuated by treatments of SB202190 (a p38 specific inhibitor) and LY294002 (an Akt specific inhibitor). In a mouse model, the GEE8080 decreased the diethylnitrosamine (DEN)-mediated elevations of serum aspartate transaminase and alanine transaminase as well as the DEN-induced hepatic lipid peroxidation. Inductions of Nrf2 and HO-1 by GEE8080 were also confirmed in the mice. In addition, the administration of GEE8080 to the mice also restored the DEN-reduced activity and protein expression of hepatic antioxidant enzymes such as superoxide dismutase, glutathione peroxidase and catalase. In conclusion, GEE8080, a 6-shogaol-rich ginger extract, may enhance antioxidant defense mechanism through the induction of Nrf2 and HO-1 regulated by p38 MAPK and PI3k/Akt pathway in vitro and in vivo.     

Differentiation of human labia minora dermis-derived fibroblasts into insulin-producing cells

Recent evidence has suggested that human skin fibroblasts may represent a novel source of therapeutic stem cells. In this study, we report a 3-stage method to induce the differentiation of skin fibroblasts into insulin- producing cells (IPCs). In stage 1, we establish the isolation, expansion and characterization of mesenchymal stem cells from human labia minora dermis- derived fibroblasts (hLMDFs) (stage 1: MSC expansion). hLMDFs express the typical mesenchymal stem cell marker proteins and can differentiate into adipocytes, osteoblasts, chondrocytes or muscle cells. In stage 2, DMEM/F12 serum-free medium with ITS mix (insulin, transferrin, and selenite) is used to induce differentiation of hLMDFs into endoderm-like cells, as determined by the expression of the endoderm markers Sox17, Foxa2, and PDX1 (stage 2: mesenchymal-endoderm transition). In stage 3, cells in the mesenchymal- endoderm transition stage are treated with nicotinamide in order to further differentiate into self-assembled, 3-dimensional islet cell-like clusters that express multiple genes related to pancreatic β-cell development and function (stage 3: IPC). We also found that the transplantation of IPCs can normalize blood glucose levels and rescue glucose homeostasis in streptozotocin- induced diabetic mice. These results indicate that hLMDFs have the capacity to differentiate into functionally competent IPCs and represent a potential cell-based treatment for diabetes mellitus.     

Meniscus induced self organization of multiple deep concave wells in a microchannel for embryoid bodies generation

Embryonic stem cells (ESCs) have attracted great interest in the fields of tissue engineering, regenerative medicine, and organogenesis for their pluripotency and ability to self-renew. ESC aggregation, which produces an embryoid body (EB), has been widely utilized as a trigger of in vitro directed differentiation. In this paper, we propose a novel method for constructing large numbers of deep concave wells in PDMS microfluidic chips using the meniscus induced by the surface tension of a liquid PDMS prepolymer, and applied this chip for the mass production of uniform sized EBs. To investigate if the microenvironment in the deep concave well is suitable for ES cells, the oxygen diffusion to the deep concave well was analyzed by CFD simulation. Murine EBs were successfully formed in the deep concave wells without loss of cells and laborious careful intervention to refresh culture media. The size of the EBs was uniform, and retrieving of EBs was done just by flipping over the chip. All the processes including EB formation and harvest are easy and safe to cells, and their viability after completion of all processes was over 95%. The basic properties of the EBs were generated and their capacity to differentiate into 3 germ layers was investigated by analyzing the gene expression profile. The harvested EBs were found to differentiate into cardiac cells and neurons, and neurofilaments formed branches of elongated extensions more than 1.0 mm in length.     

Microwave-assisted Syntheses and Crystal Structures of Benzimidazole Thiazolinone Derivatives

A rapid and efficient microwave-assisted synthesis method for the preparation of 3-(1H-benzo[d]imidazol-2-yl)-2-substituted phenyl thiazolidin-4-one (4a, 4b) was described. The structures of 4a and 4b were determined by elemental analyses, IR, 1H NMR and X-ray diffraction. In the crystals of compounds 4a and 4b, the imidazole ring and two benzene rings are planar. Interestingly, the dihedral angle between two benzene rings is 71.5° in 4a, while it is almost perpendicular in 4b due to the different benzene substituents. Meanwhile, the thiazolidinone ring is planar in 4a while slightly distorted with an r.m.s deviation of 0.1494(2) in 4b. The hydrogen bonding interactions observed link the molecules to form a dimeric unit, which may be effective in the stabilization of the structure.     

横向限制下凝固微观组织演化的相场法模拟

凝固过程中横向限制挡板的存在对晶体微观结构的演化存在重要的影响, 不同性质的横向挡板将产生不同的限制效应, 对最终凝固微观组织形成起着决定性作用. 本文利用非等温相场模型, 定性地模拟了纯金属Ni凝固过程中横向限制的存在对其枝晶微观形貌演化的影响, 研究了不同尺寸及性质的横向挡板对枝晶微观结构形成的影响, 讨论了横向限制对不同初始枝晶间距枝晶形貌发展的作用. 计算结果表明, 横向限制挡板的存在将直接影响凝固过程中微观组织的形貌演化过程并最终改变微观结构. 随着横向挡板间距的减小, 微观组织变化更加明显; 挡板初始温度越低, 枝晶形貌改变越明显; 初始枝晶间距越大, 形貌变化越明显; 不同挡板高度对微观结构具有基本相同的影响. 关键词： 相场模拟 微观组织演化 横向限制