细胞凋亡诱导剂研究进展

细胞凋亡诱导剂作为癌症治疗药物日益受到重视,并已应用于临床研究,是一类非常有应用前景的药物.综述了近年来细胞凋亡诱导剂的研究状况及进展,重点介绍了它们的结构类型及作用特点.     

Synthesis and Crystal Structure of 3,3′-(Hexane-1,6-diyl)bis(1-acetyl-5,5-dimethylhydantoin),a New Inducer of Differentiation

1 INTRODUCTION Hexamethylenebis[acetamide] (HMBA) is an effective agent in phaseⅡclinical trial[1] that induces differentiation of certain types of tumors to nonmalignant phenotypes. In an attempt to discover more efficient inducers, a number of derivatives of HMBA have been synthesized and evaluated in vitro[2, 3]. The results proved that increasing the number of functional groups could enhance the anticancer activity. In addition, it was evident that compounds with six methylene i…     

Synthesis and Crystal Structure of 3,3‘—（Hexane—1,6—diyl）bis（1—acetyl—5,5—dimethylhydantoin）,a New Inducer of Differentiation

The title compound C20H30N4O6, Mr = 422.48)was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in the triclinic system, space group P ī with cell parameters: a = 8.330(2), b = 8.468(2), c = 16.017(3) A, α = 97.30(3), β = 92.33(3), γ = 103.94(3)o, V = 1084.7(4) A3, Dc = 1.294 g/cm3, Z = 2, F(000) = 452 and μ = 0.096 mm-1. The structure was refined to R = 0.0483 for 3732 observed reflections with I>2(I) and wR = 0.1335 for 4828 unique reflections. The hydantoin rings are planar and the two ring planes of one molecule are paralleled to each other.     

受乳糖启动子控制的基因表达过程的优化

借助于ＳＤＳ－聚丙烯酰胺凝胶电泳分析方法，对乳糖诱导的由乳糖启动子控制的大肠杆菌ＲＮＡ聚合酶σ７０因子基因表达过程进行了优化研究．结果表明，含此融合基因的大肠杆菌菌株ＢＬ２１（ＤＥ３）ｐＧＥＭＤ的生长量达到ＯＤ６００ｎｍ＝１．０时，用终浓度为０．０８％的乳糖进行连续５ｈ的诱导，可使大肠杆菌ＲＮＡ聚合酶σ７０因子基因的表达量达到最大，并达到ＩＰＴＧ同样的诱导效果．流加低浓度的乳糖溶液能增加σ７０因子的合成量，但是促进作用不很显著．     

Numerical simulation of cavitating flow in 2D and 3D inducer geometries

A computational method is proposed to simulate 3D unsteady cavitating flows in spatial turbopump inducers. It is based on the code FineTurbo, adapted to take into account two‐phase flow phenomena. The initial model is a time‐marching algorithm devoted to compressible flow, associated with a low‐speed preconditioner to treat low Mach number flows. The presented work covers the 3D implementation of a physical model developed in LEGI for several years to simulate 2D unsteady cavitating flows. It is based on a barotropic state law that relates the fluid density to the pressure variations. A modification of the preconditioner is proposed to treat efficiently as well highly compressible two‐phase flow areas as weakly compressible single‐phase flow conditions. The numerical model is applied to time‐accurate simulations of cavitating flow in spatial turbopump inducers. The first geometry is a 2D Venturi type section designed to simulate an inducer blade suction side. Results obtained with this simple test case, including the study of its general cavitating behaviour, numerical tests, and precise comparisons with previous experimental measurements inside the cavity, lead to a satisfactory validation of the model. A complete three‐dimensional rotating inducer geometry is then considered, and its quasi‐static behaviour in cavitating conditions is investigated. Numerical results are compared to experimental measurements and visualizations, and a promising agreement is obtained. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up...     

The directed self-assembly of amphiphilic diblock copolymers in selective solvents

The directed self-assembly of diblock copolymers in solvents is studied systematically using a simulated annealing method. Effects of the shape, scale, and adsorption capacity of the induced surface on the morphology of the aggregates are examined. A variety of morphologies are predicted. By increasing the scale of induced surface, the micellar shape transforms from cylinder to sheet with a tail and finally to thin sheet without tail. The shape of induced surface determines the sheet’s shape, such as rounded and square. Configurations of hydrophobic blocks and interfacial energies are investigated by calculating the mean square end-to-end distances and the contact numbers between hydrophobic monomer and other species, respectively.     

关于药物对小鼠肝脏细胞色素P-450含量的影响实验结果的分析

肝药酶诱导剂苯巴比妥能诱导细胞色素P-450的合成,而肝药酶抑制剂放线菌素D能抑制细胞色素P-450的合成,本实验应用示差光谱法对P-450含量加以测定.本文改进了传统的计算药后诱导组和抑制组P-450含量增加或减少的百分比来评价药物的方法,在M athem atica数学软件环境下,对数据进行方差分析和t检验,提高了数据处理精度和可信度.并对原方法表示怀疑.     

Actinolactomycin,a New 2-Oxonanonoidal Antitumor Antibiotic Produced by Streptomyces flavoretus 18522,and its Inhibitory Effect on the Proliferation of Human Cancer Cells

In the course of our screening for new anticancer agents from microbial resources usingmammalian cancer tsFT210 cells1-3, we found that the fermentation broth of anactinomycete strain 18522 significantly inhibited the cell cycle of tsFT210 cells at theG0/G1 phase. From the fermentation broth of this strain, we have now isolated a new2-oxonanonoidal anitumor antibiotic, named actinolactomycin 1, through a bioassay-guided separation procedure. In this communication, the isolation, structure de…