Chronic morphine treatment inhibits oxytocin release from the supraoptic nucleus slices of rats

Effect of chronic morphine treatment on oxytocin (OT) release from the long term-cultured organotypic slice of the supraoptic nucleus (SON) was investigated using radioimmunoassay. The co-localization of oxytocin and mu-opioid receptor in neurons within the SON was observed with the double-labeled methods of in situ hybridization combined with immunohistochemistry. After exposure to morphine for 6days, the OT levels in culture media were significantly decreased. Naloxone caused much greater release of OT in chronic morphine treatment group than in controls. Naloxone has no effect after acute morphine treatment. 90% of OT-ir (immunoreactive) neurons expressed mu-opioid receptor mRNA in the SON and 45% of the neurons that expressed mu-opioid receptor mRNAs were OT-ir neurons. These results indicated that the neurons within SON could develop dependence on morphine in vitro, and these effects might be exerted via mu-opioid receptor in oxytocin neurons of the SON.     

Vascular endothelial growth factor receptor signaling is required for cardiac valve formation in zebrafish.

Vascular endothelial growth factor-receptors (VEGF-Rs) are pivotal regulators of vascular development, but a specific role for these receptors in the formation of heart valves has not been identified. We took advantage of small molecule inhibitors of VEGF-R signaling and showed that blocking VEGF-R signaling with receptor selective tyrosine kinase inhibitors, PTK 787 and AAC 787, from 17-21 hr post-fertilization (hpf) in zebrafish embryos resulted in a functional and structural defect in cardiac valve development. Regurgitation of blood between the two chambers of the heart, as well as a loss of cell-restricted expression of the valve differentiation markers notch 1b and bone morphogenetic protein-4 (bmp-4), was readily apparent in treated embryos. In addition, microangiography revealed a loss of a definitive atrioventricular constriction in treated embryos. Taken together, these data demonstrate a novel function for VEGF-Rs in the endocardial endothelium of the developing cardiac valve.     

Arthrobacter scleromae sp. nov. isolated from human clinical specimens

A gram-positive, coryneform bacterium was isolated from swollen scleromata of a dermatosis patient. An analysis of its phenotypic, chemotaxonomic, and genotypic characteristics showed that this bacterium is closely associated with Arthrobacter oxydans and Arthrobacter polychromogenes but that it belongs to a distinct species, for which the name Arthrobacter scleromae sp. nov. is proposed.     

髋臼CT图像轮廓跟踪方法

目的为重建和测量髋臼的解剖结构,需要大量地读取CT图像的信息,以获得髋臼轮廓的坐标值。方法本研究采用直方图阈值图像分割、kirsh边缘提取法获得髋臼的二值化轮廓图像。轮廓坐标的提取应用了“迷宫”边缘跟踪算法。结果本方法可大量、快捷、正确的提取图像轮廓信息。     

Cell cycle dependent intracellular distribution of two spliced isoforms of TCP/ILF3 proteins

TCP80 is an approximately 80kDa mammalian cytoplasmic protein that binds to a set of mRNAs and inhibits their translation in vitro and ex vivo. This protein has high sequence similarity to interleukin-2 enhancer-binding factors (NF90/ILF3) and the M-phase phosphoprotein (MPP4)/DRBP76. A 110kDa immunologic isoform of TCP80/NF90/MPP4/DRBP76, termed TCP110, also is present in cytoplasm and nuclei of many types of cells. A cDNA sequence coding for TCP110 was derived by 5(')RACE. The TCP110 sequence is identical to ILF3. The gene coding for TCP110/ILF3 mapped to human chromosome 19 and the gene organization was analyzed using TCP80 and TCP110/ILF3 cDNA sequences. The TCP/ILF3 gene spans >34.8kb and contains 21 exons. At least one alternatively spliced product involving exons 19-21 exists and predicts the formation of either TCP80 or TCP110/ILF3. However, the functional relationships of TCP80 and TCP110/ILF3 required elucidation. The metabolic turnover rates and subcellular distribution of TCP80 and TCP110/ILF3 during the cell cycle showed TCP80 to be relatively stable (t(1/2)=5 days) in the cytoplasmic compartment. In comparison, TCP110/ILF3 migrated between the cytoplasmic and nuclear compartments during the cell cycle. The TCP110 C-terminal segment contains an additional nuclear localizing signal that plays a role in its nuclear translocation. This study indicates that the multiple cellular functions, i.e., translation control, interleukin-2 enhancer binding, or cell division, of TCP/ILF3 are fulfilled by alternatively spliced isoforms.     

三氧化二砷抑制人肝癌细胞P27kip1 187位苏氨酸磷酸化

目的 探讨三氧化二砷(As2O3)对人肝癌SMMC-7721细胞的生长抑制与P27kipl第187位苏氨酸(P27Thr187)磷酸化的关系.方法 体外培养人肝癌细胞株SMMC-7721,2 μmol/L As2O3处理72 h,细胞计数法检测SMMC-7721生长,流式细胞仪检测细胞周期,核质分离、Western Blot及细胞免疫荧光技术检测P27、Thr187磷酸化的P27(p-P27T187)在SMMC-7721细胞中的表达及亚细胞定位.结果 2 ttmoVL As2O3明显抑制SMMC-7721的增殖,细胞周期阻滞在G2/M期.As2O3作用后P27蛋白总量增加,p-P27T187蛋白总量减少,并伴有Cdk2及cyclinE表达下降,同时P27发生从胞质向胞核的易位,p-P27T187核内表达减少.结论 As2O3可抑制P27T187的磷酸化,诱导P27在SMMCa721细胞核中的积聚.     

基质金属蛋白酶1与冠状动脉粥样硬化斑块破裂的关系

目的 探讨冠状动脉粥样硬化斑块破裂与基质金属蛋白酶１（ＭＭＰ－１）的关系,以及不稳定斑块中ＭＭＰ－１的来源。方法 收集２０例死于急性心肌梗死、１０例有不稳定心绞痛史,以及１２例有稳定心绞痛史的尸体解剖病例共４２例,从冠状动脉各分支取材,常规病理检查、部分节段行ＭＭＰ－１、平滑肌肌动蛋白、ＣＤ６８、ＣＤ４５ＲＯ和ＣＤ２０洒色。结果 在急性心肌梗死及不稳定心绞痛病例中,均见有斑块破裂伴血栓形成,而在稳     

基于敏感性定理的EIT重构算法仿真研究

为了研究性能更好的EIT图像重构算法，我们对基于敏感性定理的EIT图像重构算法进行了计算机仿真研究，并与几种常用图像重构算法进行比较，提出对基于敏感性定理的EIT图像重构算法的改进措施。     

细粒棘球绦虫疫苗候选分子EgA31的GST融合蛋白原核表达及纯化

目的 :构建细粒棘球绦虫疫苗候选分子EgA31重组质粒 ,表达及纯化EgA31 GST融合蛋白 ,为疫苗的研究奠定基础。方法 :PCR扩增EgA31cDNA ,将得到的cDNA经限制性内切酶酶切 ,然后亚克隆入pGEX 5X 3质粒 ,转化BL2 1宿主菌 ,IPTG诱导重组质粒的表达 ,亲和层析纯化表达产物 ,Bradford法测定重组蛋白含量 ,用SDS PAGE和Westernblot进行分析鉴定。结果 :SDS PAGE显示分离纯化的EgA31 GST融合蛋白为 4 5kDa ,测序检验重组质粒中EgA31cDNA序列正确。EgA31 GST融合蛋白免疫豚鼠得到的抗血清可与细粒棘球绦虫原头蚴总蛋白在 6 6kDa处特异性反应。结论 :EgA31 GST融合蛋白获得高效表达 ,并成功纯化 ,初步实验证明具有良好的免疫原性 ,可用于进一步疫苗的免疫注射实验