Construction and Applioation of the Gene Expressing Vector for Cynaobactorium

蓝藻是一类具植物型放氧光合作用特性的原核生物 .多数蓝藻富含营养物质 ,无毒 ,是表达外源目的基因的独特受体系统 .因此 ,构建适用于蓝藻表达外源目的基因的载体系统 ,并用于表达药物活性肽基因 ,已成为当前蓝藻基因工程研究的热点之一 .本课题组 10多年来率先在国内开展蓝藻基因工程研究 ,从蓝藻 Plectonema botyanum中分离得到了约 1.5kb的小质粒 ,以此为出发质粒 ,构建了蓝藻穿梭质粒 p PRS- 1和穿梭质粒表达载体 p PKE2 ;同时根据 DNA片段同源重组的性质 ,构建了蓝藻 Calothrix sp.PCC76 0 1、Synechococcus sp.PCC794 2的基因整合平台系统 .在国家 86 3项目经费资助下 ,利用构建的蓝藻质粒载体和基因整合平台系统 ,把人源胸腺素基因转入蓝藻 Calothrix sp.PCC76 0 1和 Synechococcus sp.PCC794 2 ,并能高效表达 ,首次获得了可直接口服的含人源胸腺素的转基因蓝藻 ,这对研究和开发基因工程口服药物具有重大的科学意义和经济、社会效益Cyanobacteria (blue green) algae, show special characters in photosynthesis, nitrogen fixation,genetics and evolution. Because most of them are not virulent and have high nutritional value, this kind of special prokaryote can become a new host system for the expression of foreign genes. It had been one of the hottest study on the genetic engineering of cyanobacteria that construction expression vector and expression of specialmedical peptide in blue green algae. For more than ten years study on genetic engineering of cyanobacteria, our group had constructed a serial of shutter plasmids from a little endocellular plasmid pPbS of cyanobacteria Plectonema boryanum, and gene integration platform system for Synechococcus sp. PCC7942 and Calothrix sp. PCC7601. Funded by national high science and technical program(863),we had succeed in expression human thymosinα1 gene in cyanobacteria Synechococcus sp. PCC7942 and Calothrix sp. PCC7601 by using these transform vector systems. The transgene blue green algae bring us a wonderful future on the genetic engineering medicine production, which has high value in both science and economic.国家自然科学基金!(39570 4 0 7);; 国家 86 3课题!(819- 0 4 - 0 3)资助项

利用新型一次性激流灌注式生物反应器培养动物细胞

利用新型一次性培养袋在5～10L激流灌注式生物反应器中培养3种贴壁和3种悬浮细胞,通过在线控制培养温度、pH值和溶氧等工艺参数,监测并分析培养过程中细胞密度、活率、糖耗等的变化情况.结果表明,贴壁培养细胞MDCK,VERO和DF-1培养6d后消化计数,密度分别达4.8×106,1.0×107和1.5×107mL-1,细胞状态良好,活率在90%以上.悬浮细胞CHO,BHK-21和Sf9经无血清悬浮驯化后,经种子链扩增,在激流式反应器中悬浮培养的初始接种密度分别为2.0×106,2.1×106和2.15×106mL-1时,培养一段时间后其最高培养密度分别可达2.0×107,2.1×107和1.8×107mL-1,维持培养时间分别为13,12和10d

用于视觉修复的视网膜下植入微芯片

为治疗由视网膜光感受器退化引起的失明，研制了一种可以满足视网膜下植入要求的光电刺激器件——硅基PIN光电探测器阵列结构微芯片，这种电刺激芯片可以在一定程度上代替因疾病受损的光感受细胞，向位于光感受细胞之后、尚未损伤的其他视网膜细胞发出电刺激，从而引发视神经的视觉冲动。微芯片制作采用了硅、硅氧化物以及金等生物相容性较好的材料。在微芯片上利用半导体工艺刻蚀隔离槽，形成一个探测器面阵，面阵上的每个探测器单元可以根据照射在其上的光强大小产生相应的刺激电流。对制作的芯片进行了生物相容性、伏安特性、响应度以及光谱特性的测量，结果表明，芯片在眼睛安全用光的范围内可以产生足够强度的刺激电流，满足动物植入实验的要求

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies