Isolation of neural precursor cells from skeletal muscle tissues and their differentiation into neuron-like cells

Skeletal muscle contains several precursor cells that generate muscle, bone, cartilage and blood cells. Although there are reports that skeletal muscle-derived cells can trans-differentiate into neural-lineage cells, methods for isolating precursor cells, and procedures for successful neural induction have not been fully established. Here, we show that the preplate cell isolation method, which separates cells based on their adhesion characteristics, permits separation of cells possessing neural precursor characteristics from other cells of skeletal muscle tissues. We term these isolated cells skeletal muscle-derived neural precursor cells (SMNPs). The isolated SMNPs constitutively expressed neural stem cell markers. In addition, we describe effective neural induction materials permitting the neuron-like cell differentiation of SMNPs. Treatment with retinoic acid or forskolin facilitated morphological changes in SMNPs; they differentiated into neuron-like cells that possessed specific neuronal markers. These results suggest that the preplate isolation method, and treatment with retinoic acid or forskolin, may provide vital assistance in the use of SMNPs in cell-based therapy of neuronal disease.     

Supramolecular assemblies built with host-stabilized charge-transfer interactions

Host-stabilized charge-transfer (CT) interactions and supramolecular assemblies built with these interactions are described. A variety of supramolecular assemblies including polyrotaxanes, molecular necklaces, and rotaxane dendrimers were synthesized through the intramolecular or intermolecular host-stabilized CT complex formation using cucurbit[8]uril (CB[8]) and D-A molecules having both electron-donor and electron-acceptor units connected by various types of linkers. Applications, including the design and synthesis of redox-driven molecular machines such as molecular loop locks, development of redox-controllable vesicles and detection of biologically important molecules, are also described.     

Conjugated polymer nanoparticles for biochemical protein kinase assay

Sensitive and reliable monitoring of kinase activity was reported by using highly efficient fluorescence resonance energy transfer of conjugated polymer nanoparticles (CPNs) to a rhodamine labelled peptide substrate.     

Effect of the residual silanol group protection on the liquid chromatographic resolution of racemic primary amino compounds on a chiral stationary phase based on optically active (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6

A liquid chromatographic chiral stationary phase (CSP) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6, which has been utilized in the resolution of alpha-amino acids, amines and amino alcohols, was treated with excess of n-octyltriethoxysilane to prepare a new improved CSP. The residual silanol groups of the original CSP were protected by n-octyl groups in the new CSP. The chiral recognition ability of the new CSP was superior to that of the original CSP in the resolution of alpha-amino acids, amines and amino alcohols. Retention factors (k1) for the resolution of alpha-amino acids were lower on the new CSP than on the original CSP while those for the resolution of amines and amino alcohols were higher on the new CSP than on the original CSP. The improved chiral recognition ability of the new CSP and the retention behaviors of the two enantiomers on the new CSP have been rationalized to stem from the removal of the non-enantioselective interactions between the analytes and the residual silanol groups of the original CSP and the improved lipophilicity of the CSP.     

Synthesis of quinolines by ruthenium-catalyzed heteroannulation of anilines with 3-amino-1-propanol

Anilines react with 3-amino-1-propanol in dioxane in the presence of a catalytic amount of a ruthenium catalyst and tin(II) chloride dihydrate together with a hydrogen acceptor to afford the corresponding quinolines in moderate yields.     

Measurements of wall shear stress of a turbulent boundary layer using a micro-shear-stress imaging chip

Measurements of wall shear-stress streaks of a turbulent boundary layer in the channel flow were carried out using a MEMS-based micro-shear-stress imaging chip, which contains about 100 sensors. The chip is designed and fabricated by surface micromachining technology. One arrray of 25 micro-shear-stress sensors in the chip that covers a length of 7.5 mm is used to measure the instantaneous spanwise distribution of the surface shear stress. The statistics of high shear-stress streaks were established. Based on the measurement, the physical quantities associated with the high shear-stress streaks, such as their length, width and peak shear-stress level, were obtained. We found out that a high correlation exists between the peak shear-stress level and front-end shear-stress slope of a high shear-stress streak. This important property is currently being applied to the deisgn of a real-time flow control logic.     

测定两干扰组分体系的新吸光度法——图解比例法的研究

当用吸光度法测定欲测组分时,在显色反应中若有两干扰组分体系存在就会使此显色反应为基础的吸光度法的实用价值大大降低。如何使这种体系克服Me_Ⅱ的干扰,顺利地测定Me_Ⅰ的含量,这是个既有理论意义又有实用价值的课题。本文试图用通常的分光光度计以图解比例法为途径解决此课题。     

合成聚乙烯基苯甲酸树脂的研究(Ⅱ)——由氯甲基化交联聚苯乙烯树脂按二步法合成

用两种二步法将交联度6％的大孔氯甲基化聚苯乙烯树脂制成了聚乙烯基苯甲酸树脂,产品氯含量均为零。     

Near‐infrared spectroscopic studies on the cure behaviors of the CAE/DGEBA blend system initiated by a thermal latent catalyst

The latent properties and cure behaviors of an epoxy blend system based on cycloaliphatic epoxy (CAE) and diglycidyl ether of bisphenol A (DGEBA) epoxy containing N‐benzylpyrazinium hexafluoroantimonate (BPH) as a thermal latent initiator were investigated with near‐infrared (N‐IR) spectroscopy. The assignments of the latent properties and cure kinetics were performed by the measurements of the N‐IR reflectance for epoxide and hydroxyl functional groups at different temperatures and compositions. As a result, this system showed more than one type of reaction, and BPH was an excellent thermal latent catalyst without any coinitiator. The cure behaviors were identified by the changes in the absorption intensity of the hydroxyl groups at 7100 cm⁻¹ with different composition ratios. Moreover, characteristic N‐IR band assignments were used to evaluate the reactive kinetics and were shown to be an appropriate method for studying the cure behaviors of the CAE/DGEBA blend system containing a thermal latent catalyst. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 326–331, 2001