Antisense EGFR sequence reverses the growth properties of human liver carcinoma cell line BEL-7404 in vitro

A recombinant plasmid containing a full length human epidermal growth factor receptor (EGFR) cDNA sequence in antisense orientation was transferred into cells of a human liver carcinoma cell line BEL-7404. Compared with the control cell clone JX-0 transferred with the vector plasmid and the parent BEL-7404 cells, the antisense EGFR transferred cell clone JX-1 showed a decreased EGFR gene expression and reduced significantly the growth potential either in anchorage-dependent or anchorage-independent growth. Furthermore, JX-1 cells appeared to be distinctly dependent on serum concentration for monolayer growth. The results suggested that antisense EGFR could partly block the EGFR gene expression and reverse the malignant growth properties of human liver carcinoma cells in vitro.     

中国异皮属线虫一新种（线虫纲：垫刃目：异皮科）

本文描述采自河北省滦县寄生于白茅Ｉｍｐｅｒａｔｅ ｃｙｌｉｎｄｒｉｃａ ｖａｒ．Ｍａｊｏｒ的异皮属线虫一新种,中华异皮线虫Ｈｅｔｅｒｏｄｅｒａ ｓｉｎｅｎｓｉｓ ｓｐ．ｎｏｖ．;新种孢囊为柠檬形,阴门膜孔为两侧单膜孔型,下桥发达有泡状突;二龄幼虫口针基部球前部略凹陷,口孔侧唇外缘融合王头晕第１环纹内,即无明显侧唇,其体侧区有３条侧线与体环纹呈不完全网格状交叉;雄虫侧区有３条侧线与体环纹呈完全网格状     

Sequence variation and genetic diversity in the giant panda

About 336–444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent. Project supported by the “8.5” Key Project of Chinese Academy of Sciences, the Chairman Foundation of Chinese Academy of Sciences, K. C. Wang Education Foundation, the Applied Basic Research Foundation of Yunnan, the National Natural Science Foundation of China, the Special Foundation for Returned Chinese Scientists, and Zoological Society of San Diego.     

从大鼠肝染色质富集具有转录活性的DNA

采用DNase消化法从大鼠肝染色质分离得到富有转录活性的DNA(sDNA)。sDNA琼脂糖凝胶电泳,在0.5—6Kb范围内背景有一片荧光,小于1Kb范围内,出现明显区带。sDNA为探针与大鼠正常肝核RNA杂交百分数(29.5%),为以总核DNA为探针杂交百分数(8.2%)的3.6倍,并高于sDNA与大鼠肝癌核RNA杂交百分数(16.4%).     

人工补充寄主卵对松林内卵蜂种群消长的影响

在不同生境的松林中,人工补充寄主卵都能提高寄生效果。但林地生境不同,寄生率有明显差异。在松阔混交林中补充寄主,其寄生率比对照提高5.5—16.2倍。植被稀疏的纯松林效果较差,补充的寄生率比对照提高3.0倍。 卵蜂种群消长随季节温度而变化,全年以5月中旬至6月下旬和9月中旬至10月中旬为两个寄生高峰。卵蜂种群与松毛虫种群的消长存在较明显的相依关系,卵蜂种群随着松毛虫种群的消长而消长。施药对卵蜂种群有较大影响,施药区比对照区的寄生率约降低一倍。在混交林中填充寄主卵,能促进卵蜂种群世代延续。在逐步改善林地生境的基础上,利用人工补充寄主,可以代替人工繁蜂放蜂。     

散白蚁属两新种(等翅目:鼻白蚁科)

中国散白蚁属种类十分丰富,已发表的种类近20种,分属两个亚属,近年来湖南省林业部门结合普查工作又采得不少白蚁标本,经整理鉴定,其中鼻白蚁科的散白蚁属有两个新种。均属于额白蚁亚属。现描述如下。模式标本保存于中国科学院动物研究所。 平江散白蚁Reticulitermes(Frontotermes)pingjiangensis Tsai et Peng新种 兵蚁(图1—5)体中型,头部橙黄色,上颚棕褐色,颚基赤黄色,触角堤脊褐黄色,触角及胸部背板乳黄色,腹部色泽浅淡,体被小毛。     

银耳属的两个新种

本文报道了银耳目银耳属的两个新种——海南银耳(Tremella hainancnsis Peng sp·nov.)和莽山银耳(Tremella mangen．Peng sp．nov.)。其形态特征,前者与网状银耳(Tremellarcticulata)近似,后者与赖特银耳(Tremella wrightii)接近。对这两个新种进行了汉文和拉丁 文描述。     

转基因传播障碍中的文化因素辨析

近年来,转基因技术与产品在中国的传播遭遇了一定障碍.科学界和相关政府部门往往从科学知识的普及角度克服这些障碍.但实际上,转基因传播障碍的背后有着更为隐蔽的反智的社会态度及对传统农业的迷恋心理,三个因素都与中国传统直观外推思维方式有关.转基因传播所面临的实际是构造自然观与有机自然观之间的冲突.对有机自然观的误读与当前弥漫的反智主义关系密切,转基因带有“高科技”的突出特征,恰恰容易成为反智主义攻击的对象.在有机自然观和“反智”传统的影响下,社会上对传统农业的迷恋有着相当的市场.在此情况下,转基因技术要克服传播障碍,必须重构环境,除了以经济动力继续推动传播工作外,也要让技术发展与人们普遍接受的自然观相结合.     

miR-125b-5p促进分枝杆菌在宿主细胞和小鼠体内存活的研究

通过观察miR-125b-5p对分枝杆菌在宿主细胞和小鼠体内存活情况的影响,探究其在抗结核免疫过程中的作用。采用不同培养基对分枝杆菌进行培养并计数;以1640培养基加10%胎牛血清培养所有实验用细胞。将终浓度50 nmol/L的miR-125b-5p 模拟物、miR-125b-5p 抑制剂及磷酸盐缓冲液(PBS)对照加入细胞后,在不同时间点收集细胞。用分枝杆菌分别感染宿主细胞(A549、THP-1和RAW264.7)以及C57BL/6小鼠。采用定量聚合酶链反应检测miR-125b-5p的表达量。结果miR-125b-5p在分枝杆菌感染的多种宿主细胞及小鼠中都显著上调表达,其中小鼠肺部的表达量提高了约15倍。分别转染模拟物和抑制剂后,再用分枝杆菌感染细胞,结果发现miR-125b-5p可促进分枝杆菌在宿主细胞内的生长。当miR-125b-5p抑制剂注射到卡介苗(BCG)感染的小鼠体内时,小鼠体内的细菌载量显著降低(P<0.05)。本研究证明miR-125b-5p可调控分枝杆菌在宿主细胞及小鼠体内的生长,在抗结核免疫过程中发挥了重要作用。进一步对其作用机制的深入研究将为临床结核病的治疗提供理论指导。