The stress response factor RpoS is required for the natural transformation of Escherichia coli

The natural transformation of Escherichia coli is a novel and recently developed system that has significance for genetic studies and the biological safety of genetic engineering. However, the mechanisms of transformation, including development of competence and DNA uptake, are not thoroughly understood. In this study, we demonstrated the effect of the general stress response regulator RpoS, which has been associated with E. coli transformation, on natural transformation performed in an “open system”. We find that RpoS is required for natural transformation but not to artificial transformation and RpoS mainly affect transformation in the liquid culture prior to plating. In the liquid culture, RpoS over-expression promotes natural transformation in early exponential phase and static incubation accumulates RpoS and promotes transformation to a limited extent. These findings provide detailed understanding of RpoS function on natural transformation.     

Microelectronics-embedded channel bridging and signal regeneration of injured spinal cords

Due to the difficulty in spinal cord regeneration with biological methods, the microelectronic neural bridge, a new concept based on microelectronic technology, is presented. The microelectronic system has been realized in the forms of hybrid and integrated circuits. The integrated circuits for neural signal detection, stimulation, and regeneration are realized in a CMOS process. In animal experiments with 100 toads, 48 rats, and 3 rabbits, nerve signals have been successfully detected from spinal cords and sciatic nerves, and functional electrical stimulation has been carried out for spinal cords and sciatic nerves. When the microelectronic system is bridged between the controlling and stimulated nerve, the relevant motion of legs and nerve signal waveforms, which are stimulated by the evoked or spontaneous nerve signal through such a system, have been observed. Therefore, the feasibility of the presented method was demonstrated.     

鄱阳湖生态经济区动漫文化创意产业发展路径研究

由于生产力信息化的变革,对文化与动漫文化产品形成的设计思维、设计方法、设计样式、传播途径与方式等提出严峻的挑战。本文就江西动漫文化产业的开发,对动漫作品、产品设计、媒介之间的产业链进行了研究与分析。     

Inhibition of E coli ATPase activity by a troponin component, TN-I, and by mitochondrial ATPase inhibitor.

The enzymic activity of Mg2+- or Ca2+-stimulated ATPase from Escherichia coli was inhibited by one of the troponin components, TN-I, and by mitochondrial ATPase inhibitor (F1-inhibitor). The inhibitory ability of component TN-I against Mg2+-stimulated AtPase activity was lost after digestion of component TN-I with trypsin. The Mg2+-stimulated ATPase activity inhibited by component TN-I was completely restored by the addition of another troponin component TN-C.     

Interaction of c-Abl and p73alpha and their collaboration to induce apoptosis.

c-Abl, a non-receptor tyrosine kinase, is activated by agents that damage DNA. This activation results in either arrest of the cell cycle in phase G1 or apoptotic cell death, both of which are dependent on the kinase activity of c-Abl. p73, a member of the p53 family of tumour-suppressor proteins, can also induce apoptosis. Here we show that the apoptotic activity of p73alpha requires the presence of functional, kinase-competent c-Abl. Furthermore, p73 and c-Abl can associate with each other, andthis binding is mediated by a PxxP motif in p73 and the SH3 domain of c-Abl. We find that p73 is a substrate of the c-Abl kinase and that the ability of c-Abl to phosphorylate p73 is markedly increased by gamma-irradiation. Moreover, p73 is phosphorylated in vivo in response to ionizing radiation. These findings define a pro-apoptotic signalling pathway involving p73 and c-Abl.     

丙烯酸钠与丙烯酸羟乙酯共聚高吸水性树脂研究

高吸水性树脂是一种吸水能力特别强、具有广泛用途和良好前景的功能高分子材料。该文介绍了采用反相悬浮聚合法合成合成交联聚丙烯酸钠与丙烯酸羟乙酯的共聚高吸水性树脂的工艺方法。具体研究了丙炮酸浓度、中和度、引发剂及交联剂用量对树脂性能的影响，制得的每克树脂吸去离子水达到８００～１２００ｇ，并且保水性能优异。     

A radiation hybrid map of the rat genome containing 5,255 markers.

A whole-genome radiation hybrid (RH) panel was used to construct a high-resolution map of the rat genome based on microsatellite and gene markers. These include 3,019 new microsatellite markers described here for the first time and 1,714 microsatellite markers with known genetic locations, allowing comparison and integration of maps from different sources. A robust RH framework map containing 1,030 positions ordered with odds of at least 1,000:1 has been defined as a tool for mapping these markers, and for future RH mapping in the rat. More than 500 genes which have been mapped in mouse and/or human were localized with respect to the rat RH framework, allowing the construction of detailed rat-mouse and rat-human comparative maps and illustrating the power of the RH approach for comparative mapping.     

大学与国家R＆D体系

现代大学都进行科学研究,都是国家R＆D体系中的重要部分,但每个国家的大学与R＆D体系之间的关系仍各具特点.从高等教育的成就和科学技术的成就来看,美国大学与R＆D体系间关系的特点值得我们研究和借鉴.     

Reactivation by glycerol and ethylene glycol of inactivated delta-aminolevulinic acid synthetase of Rhodopseudomonas spheroides.

Reactivation effects by glycerol and ethylene glycol of inactivated ALA synthetase of R. spheroids were observed. Accompanying the reactivation of the inactivated enzyme, Km value for PLP decreased to levels similar to those of the freshly prepared enzyme.     

Active regions’ setting of the extracellular ligandbinding domain of human interleukin-6 receptor

The reliable three dimensional (3-D) structure of the extracellular ligand-binding domain (V106-P322) of human interleukin-6 receptor (hIL-6R) has been constructed by means of computer-guided homology modeling techniques using the crystal structure of the extracellular ligand-binding region (K52–L251) of human growth hormone receptor (hGHR) as templet. The space location of some key residues which influence the combination ability between the receptor and the ligand has been observed and the effects of point mutagenesis of the four conservative cysteine residues on the space conformation are analyzed. The results show that the space conformation of the side-chain carboxyl of E305 plays a key role in the ligand-binding ability. Furthermore, the space conformation of the side-chain carboxyl of E305 is very important for the electrostatic potential complementarity between hIL-6R and hIL-6 according to the docking method.