Absence of expression of OKT8 antigen on cultured human, calf and rat oligodendrocytes

Monoclonal antibodies which recognize human suppressor T cells (OKT8) have been reported by Oger and co-workers to bind to cultured sheep oligodendrocytes. These authors speculated that an immune response directed at determinants shared by suppressor lymphocytes and oligodendrocytes could explain the decrease in both circulating blood suppressor T cells and oligodendrocytes in patients with multiple sclerosis. In view of the vital issue of potential cross-reactivity between oligodendrocytes and lymphocytes, we studied the binding of viable cultured calf, rat and human oligodendrocytes using monoclonal antibodies to human T cells and monocytes. We report here that we were unable to confirm the presence of shared determinants among oligodendrocytes and any leukocytes, including human T cells or monocytes. As the reported observations of lymphocyte-oligodendrocyte shared determinants could not be identified in three other species, including man, we found no evidence to support the hypothesis that such shared determinants are of importance in the pathogenesis of multiple sclerosis.     

Morphogenesis of human colon cancer cells with fetal rat mesenchymes in organ culture

The morphogenesis and cytodifferentiation of human colon cancer cells (LS174T and HT29) were examined by combining cancer cells with fetal rat digestive-tract mesenchyme in organ culture. LS174T cells migrated into the mesenchyme to form glandular structures composed of single columnar cells with their nuclei oriented basally, while HT29 cells formed cell masses with little lumen formation. Immunohistochemical studies with antibodies against carcinoembryonic antigen and secretory components showed that the composition of cell surface glycoproteins was not necessarily reversed to the normal type, even when neoplastic cells exhibited normal glandular structures.     

Rapid neutrophil adhesion to activated endothelium mediated by GMP-140.

Granule membrane protein-140 (GMP-140), a membrane glycoprotein of platelet and endothelial cell secretory granules, is rapidly redistributed to the plasma membrane during cellular activation and degranulation. Also known as PADGEM protein, GMP-140 is structurally related to two molecules involved in leukocyte adhesion to vascular endothelium: ELAM-1, a cytokine-inducible endothelial cell receptor for neutrophils, and the MEL-14 lymphocyte homing receptor. These three proteins define a new gene family, termed selectins, each of which contains an N-terminal lectin domain, followed by an epidermal growth factor-like module, a variable number of repeating units related to those in complement-binding proteins, a transmembrane domain, and a short cytoplasmic tail. Here we demonstrate that GMP-140 can mediate leukocyte adhesion, thus establishing a functional similarity with the other selectins. Human neutrophils and promyelocytic HL-60 cells bind specifically to COS cells transfected with GMP-140 complementary DNA and to microtitre wells coated with purified GMP-140. Cell binding does not require active neutrophil metabolism but is dependent on extracellular Ca2+. Within minutes after stimulation with phorbol esters or histamine, human endothelial cells become adhesive for neutrophils; this interaction is inhibited by antibodies to GMP-140. Thus, GMP-140 expressed by activated endothelium might promote rapid neutrophil targeting to sites of acute inflammation.     

Neuronal types in long-term culture of avian retina

Zusammenfassung Morphologische Befunde an Nervenzellen der Retina von Hühnerembryonen werden mitgeteilt. Mit der Bodian-Silberimprägnation in Langzeit-Gewebekulturen konnten multipolare Ganglienzellen, bipolare und Horizontalzellen, Amakrine und Synapsen identifiziert werden.

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This work was supported by the Medical Research Council of Canada.     

The dose reduction factor produced by topically applied dimethyl sulfoxide

Zusammenfassung Die früheren positiven Strahlenschutzmittel-Versuche mit äusserlich angewandtem Dimethyl-sulfoxid wurden mit verschieden grossen Strahlendosen erweitert, um den Strahlendosisreduktionsfaktor genauer zu ermitteln. Es zeigte sich, dass dieser Faktor einer Grösse von 1.35 entspricht.     

小鼠腔前卵泡卵母细胞的体外培养、体外成熟和体外受精研究

小鼠腔前卵泡在体外生长过程中，于培养液中添加血清，以及ＦＳＨ和胰岛素均对小鼠腔前卵泡的体外生长、体外成熟、体外受精起促进作用，其中以胰岛素的效果最为显著，腔前卵泡的体外成熟率和体外受精率可达６９．４％和８０．６％，但是体外受精后的体外发育率低于添加ＦＳＨ的试验组，表明ＦＳＨ有益于卵母细胞生长过程中细胞质的成熟。单层培养的卵巢颗粒细胞对腔前卵泡的体外生长也具有促进作用。将体外受精后发育至２—细胞的胚胎移植入受体鼠，胚胎可以正常着床发育。同时，卵母细胞的核仁和线粒体在培养过程中也发生相应的变化。     

The Constituents of Diterpenoids from Isodon excisa

从唇形科尾叶香茶菜叶子的甲醇提取物中，分离提取了４个对映－贝壳杉烯型二萜，并利用核磁共振氢谱和碳谱，以及质谱、红外光谱和紫外光谱等方法，对以上各化合物进行了结构鉴定．化合物１在该植物的文献中未见报道．     

利用亮度特性的形象复原

提示了从明暗图像中复原三维信息的新方法.Photometric Stereo Method(PSM)一般以直接照明为前提.在研究中采取PSM间接扩散照明,适用了漫反射成分和全反射成分所构成的混性反射模型.在混性反射模型和间接扩散照明的条件下,物体面的亮度分布比率与表面法线向量的关系中导出了反射函数.接着把得出的反射函数带入到输入在相机的物体像素亮度,从而得到发现向量.利用这个发现向量可以复原物体的三维形象.物体的三维形象复原是通过物体表面粗糙,表面反射率,还有物体像素亮度而得出的表面法线向量来求出的.因为所提示的研究采用了亮度参照表,形象复原的速度既快又准确.反射函数被广泛定义,对具有多种形态表面特性的物体适用可行.     

支持QoS的光突发交换网络偏射路由算法

指出了光突发交换(OBS)网络的一个关键问题是如何解决资源冲突,偏射路由是光网络中的冲突解决机制之一.提出了OBS网络非循环偏射路由算法(ADR),此算法基于各网络节点的路径度来确定路由中的偏射路径,支持突发数据的有序传输,将偏射路径的流量分布到具有低路径度的中间节点.利用此算法实现了区别服务以支持QoS,并通过仿真分析了其在优化OBS网络中的性能.     

潜热对激光涂敷过程中温度场的影响

应用自编子程序与通用软件ABAQUSTM联机模拟计算了考虑潜热影响的激光涂敷过程温度场的变化.为定量地考察潜热的影响,使用了考虑潜热及不考虑潜热两种分析模型.计算结果表明,在激光涂敷过程的温度场分析中,潜热的影响不是总可以忽略的,其误差取决于材料在物相转变时交界面温差的范围及材料熔解体积的大小.考虑潜热的有限元模型分析结果和忽略潜热的计算结果比较,前者显示出较低的最高温度、较小的熔池范围和较窄的热影响域.另外,在移动热源作用下潜热的影响比固定热源更为突出.与实验结果比较,证明考虑潜热的计算模型会得出更精确的结果.