Peptoid-based reprogrammable template for cell-permeable inhibitors of protein–protein interactions

The development of inhibitors of intracellular protein–protein interactions (PPIs) is of great significance for drug discovery, but the generation of a cell-permeable molecule with high affinity to protein is challenging. Oligo(N-substituted glycines) (oligo-NSGs), referred to as peptoids, are attractive as potential intracellular PPI inhibitors owing to their high membrane permeability. However, their intrinsically flexible backbones make the rational design of inhibitors difficult. Here, we propose a peptoid-based rational approach to develop cell-permeable PPI inhibitors using oligo(N-substituted alanines) (oligo-NSAs). The rigid structures of oligo-NSAs enable independent optimization of each N-substituent to improve binding affinity and membrane permeability, while preserving the backbone shape. A molecule with optimized N-substituents inhibited a target PPI in cells, which demonstrated the utility of oligo-NSA as a reprogrammable template to develop intracellular PPI inhibitors.

A peptoid-based modular approach using oligo(N-substituted alanine) as a reprogrammable template enables independent optimization of N-substituents and facile development of cell-permeable inhibitors of protein–protein interactions.     

利用多个导流装置降低大后壁车辆气动阻力的实验研究

安装在车辆尾部1边和2边上的导流装置在降低大后壁车辆气动阻力中的作用和机理已在前面的实验中得出,为了搞清安装在车辆尾部3边和4边上的导流装置在降低大后壁车辆气动阻力中的作用和机理,本文利用1/16缩比的公共汽车模型及两种类型的导流装置,在一带有可移动地面和边界层吸收装置的开放型风洞中,进行了在车辆后端面的上、下、侧边的3边和4边分别安装导流装置时车辆后部尾流区的压强恢复及气动阻力降低的实验。对每一组合的导流装置,其与车辆表面的间隙尺寸是从0mm增加到5mm,间隔为1mm。通过对不同组合、不同间隙的导流装置的压强恢复效果和阻力降低效果的实验对比和分析,最终找出了能使车辆的气动阻力降低16%左右的最佳位置组合,为新型车辆的设计和改造提供了有利依据。     

The possibility of graded-index plastic optical fibers containing lanthanide chelates for amplifiers and lasers

Absorption spectra of lanthanide ions in perfluorinated (PF) plastic solution were measured, and Judd-Ofelt parameters (Ω₂, Ω₄, Ω₆) were determined by the absorption measurements. Fluorescence spectrum of Nd³⁺ in PF plastic solution from 900 nm to 1350 nm, pumped at 580 nm, were measured for the first time.     

Synthesis and optical properties of polyimides

Polyimides are important industrial materials because of their excellent properties. They are extensively used in the electronics industry and have great potential in the field of optical communications. In this article, we discuss the effect of the polyimide structure and the processing conditions on the optical properties. Both commercially available fluorinated polyimides and polyimides synthesized in our laboratory were used in this study. The relationship between the extent of fluorination and the refractive index was studied, and it was found that fluorination reduced the refractive index as expected. Studies conducted on the structure–property relationship revealed that with the use of more rigid monomers for the polyimides, the polyimides could be modified to show a large birefringence. The extent of birefringence depended on the composition of the polymer. In addition, the processing conditions directly controlled the residual stress in the polymer films. The residual stress was an important factor in inducing light scattering, which resulted in higher optical loss. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4832–4838, 2000