心房利钠肽样免疫反应神经元在大鼠中脑和脑桥中某些锥体外系神经核内的分布

采用PAP免疫组织化学方法对大鼠中脑和脑桥内心房利钠肽(ANP)样免疫反应神经元的分布进行了研究,结果显示阳性神经元除存在于其他作者报导过的导水管周围灰质、Edinger-Westphal核、中缝核、脚间核和蓝斑核外,还存在于属于锥体外系的红核、黑质和脑桥核内,因此,推测脑内的ANP可能在锥外系对躯体运动的调节中起着一种神经递质或神经调质的作用。这为脑内ANP可能具有与液体和电解质平衡以及心血管功能的调节无关的其它作用提供了部分形态学证据。     

土牛膝碱（abidenine）的分离及结构测定

从土牛膝(Achyraanthes bidentata Bl.)的根中分离到一种新的生物碱——土牛膝碱(ubidenine),通过波谱方法测定出土牛膝碱的化学结构为5,6—二氢化—2,3,10,11—四甲氧基—二苯并[a,g]—喹嗪盐(1)。     

应用气-质联用仪测定三种螺旋藻中的甾醇成分

应用GLC/MS联用仪对室内培养的钝顶螺旋藻(Spirulina platensis (Nordstedt) Geitler)、极大螺旋藻(S.maxima (Stechell & Gardiner) Geitler)和盐泽螺旋藻(S.subsalsa Oerst)的甾醇成分进行了测定。从钝顶螺旋藻和盐泽螺旋藻中共分出11个相同的甾醇组分:胆甾醇、胆甾烷醇、芸苔甾醇、麦角甾醇、海绵甾醇、菜子甾醇、豆甾醇、24-乙基-Δ~(5,7,22)-胆甾醇、β-谷甾醇、异岩藻甾醇和4α,23,24-三甲基Δ~(5,22)-胆甾醇;从极大螺旋藻中只分离出8个甾醇组分。其中胆甾醇含量最高。4α,23,24-三甲基-Δ~(5,22)-胆甾醇为蓝藻中首次报导。     

肺心病患者血清甲状腺激素的变化

本文分析30例慢性肺心病心衰并呼衰患者(心衰并呼衰组)及30例慢性肺心病心衰无呼衰患者(心衰无呼哀组)和慢性肺心病死亡组的血清甲状腺激素水平。结果表明心衰并呼衰组T_3、T_4水平均值显著低于心衰无呼衰组和健康组,心衰无呼衰组T_3水平均值显著低于健康组,肺心病死亡组T_3、T_4水平均值显著低于存活组,并发现血清T_3、T_4水平与动脉血氧分压(PaO_2)呈正相关。作者认为T_3明显降低是重症肺心病的损伤性结果,预示病情严重,预后差。而T_4明显下降,可能是死亡的信号之一。     

双拷贝人α型心钠素基因的组建及大肠杆菌分泌型克隆与表达

将单拷贝人α心钠素基因3′端用Ban Ⅱ酶解除去包括终止密码在内的36个碱基对,代之以人工合成的含Glu-Lys-Phe-Glu连接片段与另一单拷贝人α心钠素基因的5′端串连成编码60肽的双拷贝心钠素基因,克隆于大肠杆菌分泌型表达载体pIN-Ⅲ-OmpA_2质粒中,表达生成60肽的双拷贝人α型心钠素衍生物,在信号肽的作用下分泌至胞膜间质并自动切割为60肽的外源基因产物。分子量约8K的表达产物用分子筛或超滤膜分离后再经HPLC纯化,表达产物具有明显的心钠素放免活性和舒张血管活性。     

Identification of a neutralization epitope on the envelope gp46 antigen of human T cell leukemia virus type I and induction of neutralizing antibody by peptide immunization.

We have generated a number of mAb against various epitopes on the external envelope glycoprotein, gp46, of human T cell leukemia virus type I (HTLV-I) from a WKA rat immunized with a recombinant vaccinia virus containing the HTLV-I env gene. Among these mAb, one group of mAb, represented by a mAb designated LAT-27, could neutralize the infectivity of HTLV-I, as determined by a HTLV-I-mediated cell fusion inhibition assay. LAT-27 also interfered with transformation of normal T lymphocytes by HTLV-I in vitro. An antibody-binding assay using overlapping synthetic oligopeptides showed that LAT-27 bound specifically to 10-mer peptides that contained the gp46 amino acid sequence 191-196 (Leu-Pro-His-Ser-Asn-Leu). Antibodies from HTLV-I+ humans interfered with the binding of LAT-27 to gp46 Ag. Sera from rabbits immunized with a LAT-27-reactive peptide, 190-199, conjugated with OVA, but not sera from OVA-immunized rabbits, reacted with gp46 Ag and neutralized infectivity of HTLV-I. These results show that the HTLV-I neutralization epitope recognized by LAT-27 locates to the gp46 amino acids 191-196, and that immunization with a peptide containing the LAT-27 epitope can elicit an HTLV-I neutralizing antibody response.     

1,4—二取代酰氨基硫脲类化合物(DATCDs)的植物生理效应与应用研究——Ⅴ.DATCD-A对离体黄瓜子叶扩张及核酸代谢的影响

本实验以离体黄瓜子叶为材料,研究了 DATCD—A 对子叶扩张及核酸代谢的影响。结果表明,DATCD—A 可显著地促进离体黄化子叶扩张,使其鲜重明显增加;并且在处理后期逐渐提高子叶干重。在离体子叶扩张变绿的过程中,DATCD—A 促进离体黄化子叶 RNA、DNA 含量和 DNA/RNA 比率明显上升,且 RNA 的增加发生在 DNA 合成增加之前。凝胶电泳证明,RNA 的增加主要是25s 和18s 的 rRNA。     

基因定点诱变删除及天然α型心钠素的分泌型表达

用基因定点诱变技术,删除了pO_1α ANF表达质粒中的33对碱基,使人α型心钠素结构基因直接与大肠杆菌分泌型表达质粒pIN-Ⅲ-OmPA中的信号肽酶切位点编码区相连,构成天然人α型心钠素的表达质粒pANF,在IPTG诱导下表达28肽的天然人α型心钠素。纯化后的表达产物具有天然心钠素的放免活性和很强的舒张血管的生物活性。     

Function of the N-terminal half of RepA in activation of Rts1 ori.

The RepA protein of the Rts1 plasmid, consisting of 288 amino acids, is a trans-acting protein essential for replication. A mutant repA gene, repA delta C143, carrying a deletion that removed the 143 C-terminal amino acids of RepA, could transform, but at a low frequency, an Escherichia coli polA strain, JG112, when repA delta C143 was cloned into pBR322 with Rts1 ori in the natural configuration. The transformation was less efficient without the dyad DnaA box in the ori region, and no transformation occurred at 42 degrees C, characteristic of Rts1 replication. A fusion of the 3'-terminal half of repA of the P1 plasmid to repA delta C143 yielded a pBR322 chimeric plasmid that contained Rts1 ori through hybrid (Rts1-P1) repA. This plasmid was maintained much more stably in JG112 at 37 degrees C. At 42 degrees C, however, it was quite unstable. The overproduced hybrid RepA protein showed interference with mini-Rts1 replication in trans and also exhibited an autorepressor function, although both activities were decreased. These findings suggest that the N-terminal half of the RepA molecule of Rts1 is involved in the activation of the replication origin.