抗人CD20单克隆抗体诱导Daudi细胞凋亡的功能研究

目的　观察由基因重组抗原制备的抗人CD2 0单克隆抗体 (CD2 0 McAb) 1- 2 8对B淋巴瘤细胞的促凋亡作用 ,并探讨其作用机理。方法　利用流式细胞术测定所获 1- 2 8单抗对标准CD2 0 FITC单抗的竞争抑制作用及对胞内游离钙的影响 ;通过电镜观察其诱导Daudi细胞凋亡后形态上的改变 ,免疫印迹实验显示Daudi细胞凋亡后功能上的变化。结果　 1- 2 8能明显竞争标准CD2 0 FITC单抗与Daudi细胞表面CD2 0分子的结合。电镜结果证实了 1- 2 8能够促进Daudi细胞发生凋亡的结论 ;实验结果显示Daudi细胞与 1- 2 8作用后胞内游离钙浓度明显升高 (P <0 .0 5 ) ,细胞内Bcl 2蛋白和caspase酶原的表达量下降 ,而Bax蛋白和caspase酶原降解的活性产物表达增加。结论　 1- 2 8能竞争结合Daudi细胞表面的CD2 0分子并诱导其发生凋亡     

STAT3 couples with 14-3-3σ to regulate BCR signaling,B-cell differentiation,and IgE production

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Mutational analysis of the yeast multidrug resistance ABC transporter Pdr5p with altered drug specificity

Multidrug resistance ABC transporter Pdr5p of Saccharomyces cerevisiae is particularly important due to its ability to export a wide range of unrelated substrates. To clarify its function, we generated Pdr5p mutants by random mutagenesis and screened for mutants with altered drug specificity in vivo by using 5 drug compounds. Nine point mutations that caused significant changes in drug specificity distributed throughout the length of Pdr5p, namely, in the extracellular, transmembrane or cytoplasmic regions of the transporter. We then investigated their effects upon drug resistance, using 36 chemically related or distinct substrates. From this study, overall geometry of the Pdr5p was suggested to contribute in acquiring the enormous range of drug specificity. Based on their ability to inhibit the growth of the mutant strains, the 36 tested drugs were classified into: drugs to which the mutants responded differently (Group 1), drugs to which all the mutants showed sensitivity (Group 2), and drugs to which all the mutants exhibited resistance (Group 3). The ability of the compounds to be partitioned to the plasma membrane seemed an important factor for recognition by Pdr5p.     

Astrocytes give rise to oligodendrogliomas and astrocytomas after gene transfer of polyoma virus middle T antigen in vivo

The cells of origin for oligodendrogliomas and astrocytomas are not known but are presumed to be oligodendrocyte and astrocyte precursors, respectively. In this paper we report the generation of mixed gliomas from in vivo transformation of glial fibrillary acidic protein (GFAP)-positive cells (differentiated astrocytes) with polyoma virus middle T antigen (MTA). MTA is a powerful oncogene that activates a number of signal transduction pathways, including those proposed to be involved in gliomagenesis, and has been shown to induce tumors in many cell types. We have achieved transfer of MTA expression specifically to GFAP(+) cells in vivo using somatic cell gene transfer, and find resultant formation of anaplastic gliomas with mixed astrocytoma and oligodendroglioma morphological features. We conclude that GFAP- expressing astrocytes, with appropriate signaling abnormalities, can serve as the cell of origin for oligodendrogliomas, astrocytomas, or mixed gliomas.     

支气管哮喘病人焦虑与生命质量的相关性研究

目的　评估支气管哮喘病人焦虑与生命质量的水平 ;探讨支气管哮喘病人焦虑与生命质量的关系 .方法应用状态 -特质焦虑问卷 (STAIFORMY)和世界卫生组织生命质量量表简表 (WHOQOL -BREF) ,分别对支气管哮喘门诊病人和健康对照人群的焦虑和生命质量水平进行问卷调查 .结果　哮喘组状态焦虑为 45 1± 9 7,特质焦虑为46 5± 9 7,生命质量为 87 3± 13 2 ;健康组的状态焦虑为 3 7 7± 7 4,特质焦虑为 3 8 4± 8 1,生命质量为 95 4± 11 7.哮喘组状态焦虑、特质焦虑与生命质量均负相关 ,相关系数分别为 - 0 69和 - 0 79.结论　①支气管哮喘病人的状态焦虑及特质焦虑水平均高于健康人群 ,生命质量水平低于健康人群 ;②支气管喘病人的焦虑与生命质量负相关 .因此 ,在护理实践中应对哮喘病人进行焦虑的心理护理 ,提高其生命质量     

人脐静脉内皮细胞清除补体攻膜复合物的机制

目的：探讨内皮细胞清除补体攻膜复合物（MAC）的途径及其清除动力学，方法：原代培养的人脐静脉内皮细胞以RH414荧光标记质膜双层，0℃组装亚溶剂量的MAC，37℃复苏后，LSCM实时监MAC沉积诱导的质膜囊泡化形成和胞吞，胞吐情况,流式细胞仪定量检测内皮细胞表面MAC抗原的清除情况，结果：MAC沉积后，内皮细胞有的质膜囊泡化形成，囊泡以胞吞和胞吐2种方式离开细胞，并以前者占优，37度条件下，内皮细胞清除表面MAC的半衰期约为5min。结论：内皮细胞可通过胞吞和胞吐2种机制清除细胞表面沉积的MAC，并以胞吞方式为主。     

大白鼠下丘脑促肾上腺皮质激素(ACTH)样免疫反应神经元的分布及功能意义

本文应用免疫细胞化学技术观察大白鼠下丘脑促肾上腺皮质激素样神经元胞体,纤维及串珠样膨体的分布。胞体位于弓状核、下丘脑前核的腹侧、视上背侧连合、室周层的腹侧区及乳头体核腹侧。纤维及串珠样膨体广泛地分布于下丘脑,串珠样膨体在室旁核和室周层密集。串珠样膨体贴室管膜分布,伸至室管膜下神经毯,有的穿行室管膜上皮细胞之间并多与室管膜上皮细胞接触或穿过室管膜上皮细胞之间至第三脑室腔。在第三脑室侧壁的室管膜上皮细胞之间偶见促肾上腺皮质激素反应细胞。室旁核区促肾上腺皮质激素免疫反应串珠样膨体可能作用于催产素和后叶加压素神经元,控制催产素和后叶加压素的分泌和释放。室周层的串珠样膨体直接与脑脊液接触可认为是促肾上腺皮质激素神经元释放分泌产物的另一途径。     

不同年龄组儿童甲状腺测量值及其变化的研究

调查了90具童尸用状腺的基本形态,可分四型。其中以甲状腺由两侧叶及峡部组成者为最多,占50.22%。测量了甲状腺各部的长、宽、厚。分年龄组进行了数据的统计学处理,并计算出儿童与成人甲状腺各部相应值的百分比。结果显示:小儿甲状腺侧叶的长度和宽度在幼儿期(1—3岁)就已发育近成人的一半。随着年龄的增长,甲状腺各部的均值逐渐增加。除各部的宽度以及锥体叶的长度外,各相邻两组间同项均数的比较,经双侧T检验发现差异具有高度显著性(P<0.01)。     

乳腺富糖原透明细胞癌2例报道及文献复习

目的 探讨乳腺富糖原透明细胞癌临床病理特点及鉴别诊断要点。方法 对2例乳腺富糖原透明细胞癌进行临床资料及光镜和免疫组化标记观察。结果 组织学特点：癌细胞为多边形或柱状，胞界清楚，胞质透明，呈实性巢状、片状排列，可有乳头形成。表现为导管内癌和浸润性癌结构。免疫组化染色显示：癌细胞呈上皮性免疫表型，CK(AE1)、CEA强阳性，不表达S-100蛋白、肌动蛋白。PAS染色阳性。结论 富含糖原透明细胞癌是上皮性特殊类型乳腺癌，其诊断主要依靠组织病理学和免疫组化标记。