家蚕线粒体ND2、COⅠ和若干tRNA基因的克隆及序列分析

克隆并测定了家蚕（Bombyx mori）线粒体基因组3468bp的EcoRⅠ和HindⅢ双酶一段序列,根据序列同源性比较,该DNA片段包括3个蛋白质编码基因：ND2基因、COⅠ基因和COⅡ基因5′端399bp的序列,以及6个tRNA基因和一个尚待确定的tRNA^Met基因。家蚕与果蝇的ND2基因序列同源性约69.7%,COⅠ基因的同源性约83.8%,COⅡ基因5′端的同源性约80％,这表明细胞色素氧化酶基因在物种间比烟酰胺腺漂呤二核苷酸脱氢酶基因保守,6个推定的tRNA基因序列与果蝇相应tRNA基因序列差异较大,另外,除tRNA^Chn基因的二级结构相似外,其它tRNA基因的二级结构与果蝇相应tRNA基因的二级结构也有较大差异。     

Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells

The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.     

慢性缺氧对大鼠肺内皮素表达的影响

本文以ＡＢＣ法和原位杂交技术,观察了慢性缺氧时大鼠肺组织内内皮素－１（ＥＴ－１）的表达情况,结果发现：①正常肺血管内皮细胞有少许ＥＴ－１样阳性染色物质呈现。②缺氧ＩＷ后,肺内ＥＴ－１含量增加,主要位于肺血管内皮细胞和支气管粘膜上皮细胞。③缺氧２Ｗ和３Ｗ后,ＥＴ１阳性免疫物质进一步增加,于肺泡细胞内也见到阳性染色。④缺氧１Ｗ后肺内ＥＴ－１ｍＲＮＡ表达增加,缺氧２Ｗ和３Ｗ后,ＥＴ－１ｍＲＮＡ的表达进一步加强。提示缺氧可刺激肺内ＥＴ－１ｍＲＮＡ的表达,慢性缺氧时肺内ＥＴ－１持续分泌增加,这可能是缺氧性肺动脉高压发生的重要因素之一。     

双波长法用于磺酸型树脂吸附BSA和trypsin的研究

考察了H^ 和Na^ 变化对紫外吸收单波长法、双波长法和考马斯亮蓝法的影响。结果表明双波长法比考马斯亮蓝法和单波长法稳定性要好。选择双波长法用于磺酸型离子交换树脂吸附胰蛋白酶(trypsin)和牛血清白蛋白(BSA)的检测,结果表明：交换容量为4-88mmol／g的树脂对BSA和trypsin的吸附速率和饱和吸附量均高于交换容量为3．17mmol／g的树脂。     

Effects of thymic polypeptides on the thymopoiesis of mouse embryonic stem cells

The thymus provides a unique cellular and hormonic microenvironment for the development of immunocompetent T cells. Thymic polypeptides have been widely used clinically for the treatment of tumors, infectious diseases and immune deficiency diseases. They have already shown the ability to stimulate the maturation of hematopoietic stem cells towards the CD3+CD4+ T cell lineage. However, their effects on the thymopoiesis of embryonic stem cells are still unexplored. In this paper, we compared the effects of three thymic polypeptides, thymopentin (TP5), thymosin alpha-1 (Talpha-1) and thymopeptides on the in vitro thymopoiesis of mouse embryonic stem (ES) cells. Using the embryoid body induction system, we found that both Talpha-1 and thymopeptides effectively induced ES cells to differentiate sequentially into the CD3+ and CD4+/CD8+ T cells. These T cells had T cell receptor (TCR) Vbeta gene rearrangement and most were TCRalphabeta T cells. We also found that the expression of the Notch receptor and its ligands Delta-like-1 and Delta-like-4 gradually increased during the induction. However, TP5 failed to induce the T cell differentiation of the ES cells. In summary, this is the first report to demonstrate that Talpha-1 can stimulate the T cell early stage differentiation from ES cells using the embryoid body protocol. These findings provide a powerful model for studying T cell development and may open new venues for the clinical application of Talpha-1.     

中国蚜科新纪录,3

在调查云南森林昆虫中发现下述种类为我国首次纪录。 埃二尾蚜Cavariella aegopodii(scopoli,1763),中国新纪录。采自云南丽江(黑龙潭,1980.V.25),各型孤雌蚜。寄主为茴香,取食于嫩叶反面,叶向反面微卷。活体绿色,有翅孤雌蚜腹部背面有斑纹,有翅若蚜背面有翠绿色斑。国外分布于日本,欧洲,非洲,澳洲和美洲。 康二尾蚜Cavariella konoi Takahashi,1939,中国新纪录。采自云南剑川(老君山,3100m,1980     

植物钾营养高效分子遗传机制

钾是植物生长发育所必需的矿质营养元素之一。不同种类植物的钾营养效率存在差异, 已有证据表明这种差异是受遗传基因控制的。植物细胞依靠细胞膜上的各种钾转运体和通道蛋白吸收和转运钾离子, 这些膜蛋白的活性调控是植物钾营养效率调控的关键和基础。本文对植物钾营养高效性状分子遗传机制以及相关基因的分子功能和调控机制的研究进展进行了简要评述, 并讨论了改善作物钾营养高效性状的可能途径。     

Interaction between GAMs and Mean Flow Shear During SMBI Injection into HL-2A Tokamak

Plasma Physics Reports - The interactions among geodesic acoustic modes (GAMs), mean flow, and mean flow shear were investigated using Langmuir probe arrays under periodic supersonic molecular beam...