Effect of copper excess on peripheral blood T-lymphocytes in the chicken

Experimental study was conducted to examine the effect of copper excess on the peripheral blood T-lymphocyte by the methods of flow cytometry （FCM） and experimental pathology. 420 one-day-old Avian chickens were randomly divided into seven groups, and fed on diets as follows： 1. controls （Cu 11mg/kg） and 2. copper excess （ Cu 100mg/kg, copper excess group Ⅰ; Cu 200mg/kg, copper excess group Ⅱ; Cu 30（hng/kg, copper excess group Ⅲ; Cu 400mg/kg, copper excess group Ⅳ; Cu 500mg/kg, copper excess group Ⅴ; Cu 600mg/kg, copper excess group VI） for six weeks. The results were as follows- 1 ） In thymus, lymphocytes in the medulla were decreased in number in copper excess groups Ⅲ,Ⅳ,Ⅴ, and Ⅵ, and the increased and enlarged thymic corpuscles and the proliferated reticular cells were also observed in both copper excess group V and copper excess group VI in comparison with those of control group. 2） The percentage of CD4＋ T cells was markedly decreased from 2 to 6 weeks of age in copper excess groups Ⅳ, Ⅴ and Ⅵ （P 〈0.05 or P 〈0.01）. 3） The percentage of CD8＋ T cell was not varied in six copper excess groups during the experiment when compared with that of control group （ P 〉 0.05 ）. 4） The CD4 ＋ / CD8＋ ratio was lower from 2 to 6 weeks of age in copper excess groups Ⅳ, Ⅴ and VI than in control group （ P 〈0.05 or P 〈0.01）. 5） It was concluded that dietary copper in excess of 300mg / kg suppressed the development of T-lymphocytes and reduced the percentage of CD4＋ T cells and the CD4＋/CD8＋ ratio, and resulted in pathological injury of the thymus. Cellular immune function was finally impaired.     

Metastasis: cell-autonomous mechanisms versus contributions by the tumor microenvironment

The fatality of cancer predominantly results from the dissemination of primary tumor cells to distant sites and the subsequent formation of metastases. During tumor progression, some of the primary tumor cells as well as the tumor microenvironment undergo characteristic molecular changes, which are essential for the metastatic dissemination of tumor cells. In this review, we will discuss recent insights into pro-metastatic events occurring in tumor cells themselves and in the tumor stroma. Tumor cell-intrinsic alterations include the loss of cell polarity and alterations in cell-cell and cell-matrix adhesion as well as deregulated receptor kinase signaling, which together support detachment, migration and invasion of tumor cells. On the other hand, the tumor stroma, including endothelial cells, fibroblasts and cells of the immune system, is engaged in an active molecular crosstalk within the tumor microenvironment. Subsequent activation of blood vessel and lymph vessel angiogenesis together with inflammatory and immune-suppressive responses further promotes cancer cell migration and invasion, as well as initiation of the metastatic process. Received 4 July 2005; received after revision 3 November 2005; accepted 14 November 2005     

上海天马山蝉花的初步研究

对采自上海天马山的蝉花进行分离获得纯菌种 ,并在米饭培养基上培养得到长棒状体     

Altered proteoglycan gene expression and the tumor stroma

Tumor stroma is a specialized form of tissue that is associated with epithelial neoplasms. Recent evidence indicates that significant changes in proteoglycan content occur in the tumor stroma and that these alterations could support tumor progression and invasion as well as tumor growth. Our main hypothesis is that the generation of tumor stroma is under direct control of the neoplastic cells and that, via a feedback loop, altered proteoglycan gene expression would influence the behavior of tumor cells. In this review, we will focus primarily on the work from our laboratory related to the altered expression of chondroitin sulfate proteoglycan and its role in tumor development and progression. The connective tissue stroma of human colon cancer is enriched in chondroitin sulfate and the stromal cell elements, primarily colon fibroblasts and smooth muscle cells, are responsible for this biosynthetic increase. These changes can be reproduced in vitro by using either tumor metabolites or co-cultures of human colon carcinoma cells and colon mesenchymal cells. The levels of decorin, a leucine-rich proteoglycan involved in the regulation of matrix assembly and cell proliferation, are markedly elevated in the stroma of colon carcinoma. These changes correlate with a marked increase in decorin mRNA levels and a concurrent hypomethylation of decorin gene, a DNA alteration associated with enhanced gene expression. Elucidation of decorin gene structure has revealed an unexpected degree of complexity in the 5 untranslated region of the gene with two leader exons that are alternatively spliced to the second coding exon. Furthermore, a transforming growth factor beta (TGF-)-negative element is present in the promoter region of decorin gene. This regulatory domain is likely to be implicated in the silencing of decorin gene by TGF- and may contribute to the regulation of this matrix gene in the tumor stroma.     

原发性血小板减少性紫癜患者胸腺近期输出功能状态

目的:了解原发性血小板减少性紫瘢(ITP)患者胸腺近期输出功能的状态,评价其T细胞潜能.方法:采用实时定量PCR(TaqMan)方法检测15例ITP患者外周血单个核细胞(PBMCs)中T细胞受体重排删除DNA环(TRECs)的含量,17例正常人作为对照.结果:正常人外周血中每1 000个PBMCs中TRECs拷贝数为(3.76±3.42),ITP患者TRECs水平变化较大[每1000个PBMCs中TRECs拷贝数为(2.60±2.99)],4例病人未能检测到TRECs,病人平均TRECs水平与正常人的差异没有显著性(P＞0.05),女性病人TRECs水平略高于男性(P=0.499),但无统计学意义.结论:多数ITP患者外周血初始T细胞水平和胸腺近期输出功能保持正常水平.     

空间微重力环境对人牙髓间充质细胞的影响初探

通过实际空间搭载实验,研究空间环境对人牙髓间充质细胞的影响。将人牙髓间充质细胞无源(细胞保存于密闭环境条件中,没有细胞培养所需的5%CO2、37℃、饱和湿度标准条件的适宜环境)搭载长征2号飞船进入空间环境,空间飞行时间为17d,返回地面后,继续培养成活并传代,观察其细胞骨架的改变。激光共聚焦显微镜观察显示:空间实验组细胞骨架出现弥散性的变化,局部微丝解聚。实验结果表明:人牙髓间充质细胞经历空间飞行后可以继续成活,并且细胞骨架发生了明显改变。     

黄化型大麦的系列研究 Ⅵ 南黄大麦叶绿体超微结构的发育

本文报道了黄化型大麦不同生育期叶绿体的发育情况.三叶期时叶绿体的基质片层简单分散,类囊体垛叠极少;分蘖期时类囊体膜较复杂,并与叶绿体长轴平行,拨节期时类囊体垛叠增多;灌浆期时片层较复杂,但均不及正常的原品种早熟三号三叶期时的垛叠多.黄化型大麦在个体发育过程中叶绿体的片层是逐渐发育而复杂化的.这个过程,反映了叶绿体的演化历史,说明了在光合作用中的重要作用,具有理论和实践上的价值.     

壳聚糖植入兔角膜的生物学反应

目的：探讨壳聚糖植入兔角膜的生物相容性，以评价其作为人组织工程角膜材料的可行性。方法：将壳聚糖材料制成的膜植入新西兰兔角膜的板层内，进行裂隙灯观察并进行组织病理学检查。结果：术后1周有结膜睫状充血，角膜水肿；2周后充血水肿逐渐消失。兔眼的情况稳定，术后2周角膜半透明；术后8周新生血管消退，材料与角膜的生物相容性好，材料部分吸收溶解，角膜透明。电镜超微结构检查可见兔角膜标本中材料内有角膜基质细胞长入，细胞胞浆较多，细胞器丰富，有大量的新生胶原。结论：壳聚糖与角膜组织具有良好的生物相容性，且能自然溶解吸收，可用作组织工程角膜的载体材料。