双功能抗体介导的胃癌杀伤效应

将诱变的αＣＤ３杂交瘤（ＴＫ~－）与ＰＤ４杂交瘤（ＨＧＰＲＴ~－）融合,获得分泌双功能抗体（ＢｓＡｂ）的四体杂交瘤Ｃ３．ＢｓＡｂＣ３可分别与ＣＤ３分子及胃癌相关抗原Ｐ４０反应．体外杀伤试验证实,当效靶比为４０：１,ＢｓＡｂＣ３浓度为１ｍｇ／Ｌ时,其杀伤效应可达７７．６％．该杀伤效应具有明显的特异性,仅Ｐ４０阳性表达的靶细胞可被溶解,体内杀伤试验证实,裸鼠接种胃癌细胞后５ｄ,以ＢｓＡｂＣ３活化的外周血淋巴细胞（ＰＢＬｓ）经局部皮下注射处理,可使移植胃癌完全消退（５／５）．这一明显的治疗作用可能与局部注射途径有关,可供临床应用参考．     

不同生长期蛋鸡的体脂水平和肝脏脂肪酸合成酶活性的关系

 不同生长期蛋鸡的体脂水平和肝脏脂肪酸合成酶活性的关系田维熙,董妍,权晖,陈文峰（中国科学院研究生院生物教学部,北京１０００３９）动物体脂的控制是一个复杂过程．不同种类不同年龄的动物体脂水平有很大差异,控制机制是什么,哪些是关键的控制因素？不久前我们曾...     

CaM BP－10对NAD激酶的抑制效应

ＮＡＤ激酶在光合作用等植物生理过程中起重要作用。ＮＡＤ激酶的激活依赖于钙离子和钙调素（ＣａｌｍＯｄｕｌｉｎ,ＣａＭ）．从植物中分离得到的一种新的ＣａＭ结合蛋白ＣａＭＢＰ－１０（ＢＰ－１０）明显抑制ＮＡＤ激酶的激活活性,抑制作用可被ＣａＭ所克服．动力学研究表明,抑制效应是ＢＰ－１０与ＣａＭ之间特异性相互作用的结果。实验证实ＢＰ－１０对ＮＡＤ激酶活性起着重要调节作用．     

The distribution of Gossypium hirsutum chromatin in G. barbadense germ plasm: molecular analysis of introgressive plant breeding

Cotton is unusual among major crop plants in that two cross-fertile species are widely cultivated for a common economic product, fiber. Both historical evidence and classical genetic studies suggest that many improved forms of Gossypium barbadense (Sea Island, Egyptian, and Pima cottons) may include chromatin derived from G. hirsutum. Using 106 restriction fragment length polymorphism (RFLP) loci well distributed across the cotton genome, we revealed the amount and genomic distribution of G. hirsutum chromatin in 54 G. barbadense collections from around the world. The average G. barbadense collection was comprised of 8.9% alleles apparently derived from G. hirsutum. Pima cultivars (7.3 %) had fewer G. hirsutum alleles than Sea Island (9.0%) or Egyptian (9.6%) cultivars. G. hirsutum alleles were not randomly distributed, as 57.5% of the total introgression observed was accounted for by five specific chromosomal regions that span less than 10% of the genome. The average length of an introgressed chromosome segment was 12.9 cM. Overlap of introgressed chromatin in different breeding programs hints that retention of these G. hirsutum chromosomal segments may impart a selective advantage to G. barbadense genotypes. Although cluster analysis generally grouped germ plasm from common classes and/or breeding programs together, no 2 genotypes were identical — thus differences in the length and repertoire of introgressed chromosome segments also permit DNA fingerprinting of G. barbadense cultivars.     

Regulation of cellulase synthesis in mycelial fungi: Participation of ATP and cyclic AMP

Summary ATP and cAMP in 4 strains of mycelial fungi were determined by luciferin-luciferase system and HPLC respectively. Cellulase synthesis was subject to the dual control of ATP and cAMP. No matter what carbon sourse was used, cellulase synthesis was repressed if intracellular ATP concentration was over 10^-7mg/ml. Exogenous cAMP could increase cellulase synthesis under depression conditions.     

The NADP-linked glyceraldehyde-3-phosphate dehydrogenases of Anabaena variabilis and Synechocystis PCC 6803, which lack one of the cysteines found in the higher plant enzyme,are not reductively activated

Light activation of NADP-linked glyceraldehyde-3-P dehydrogenase involves reductive cleavage of a disulfide bond. We have proposed that the inactivating disulfide locks the two domains of the enzyme, preventing catalysis, and we have tentatively identified the two critical cysteine residues in the chloroplast enzyme (D. Li, F.J. Stevens, M. Schiffer and L.E. Anderson (1994) Biophys J. 67: 29–35). We reasoned that if activation of this enzyme involves these cysteines that enzymes lacking one or both should be active in the dark and insensitive to reductants. One of these cysteines is present in the enzymes from Anabaena variabilis and Synechocystis PCC 6803 but the other is not. Consistent with the proposed mechanism, glyceraldehyde-3-P dehydrogenase is not affected by DTT-treatment in extracts of either of these cyanobacteria. Fructosebisphosphatase is DTT-activated in extracts of both of these cyanobacteria and glucose-6-P dehydrogenase is inactivated in Synechocystis, as in higher plant chloroplasts. Apparently reductive modulation is possible in these cyanobacteria but glyceraldehyde-3-P dehydrogenase is not light activated.     

Purification, properties, and immunological characterization of GalT-3 (UDP-galactose: GM2 ganglioside, β1-3 galactosyltransferase) from embryonic chicken brain

A 1-3 galactosyltransferase (GalT-3; UDP-Gal; GM2 1-3galactosyltransferase) was purified over 5100-fold from 19-day-old embryonic chicken brain homogenate employing detergent solubilization, -lactalbumin Sepharose, Q-Sepharose, UDP-hexanolamine Sepharose, and GalNAc1-4Gal-Synsorb column chromatography. The purified enzyme was resolved into two bands on reducing gels with apparent molecular weights of 62 kDa and 65 kDa, respectively. GalT-3 activity was also localized in the same regions by activity gel analysis and sucrose-density gradient centrifugation of a detergent-solubilized extract of 19-day-old embryonic chicken brain. Purified GalT-3 exhibited apparentK _mS of 33 µm, 22 µm and 14.4mM with respect to the substrates GM2, UDP-galactose, and MnCl₂, respectively. Substrate specificity studies with the purified enzyme and a variety of glycosphingolipids, glycoproteins, and synthetic substrates revealed that the enzyme was highly specific only for the glycosphingolipid acceptors, GM2 and GgOse3Cer (asialo-GM2). Ovine-asialo-agalacto submaxillary mucin inhibited the transfer of galactose to GM2 but did not act as an acceptor in the range of concentrations tested. Polyclonal antibodies raised against purified GalT-3 inhibited GalT-3 activityin vitro and Western-immunoblot analysis of purified GalT-3 showed immunopositive bands at 62 and 65 kDa.Abbreviations CNS central nervous system - GM1 monosialotetraosylganglioside, Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer - GM2 monosialotriaosylganglioside, GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer - DSS detergent solubilized supernatant - ECB embryonic chicken brain - TBS Tris-buffered saline     

Evidence for selective effects of vanadium on adipose cell metabolism involving actions on cAMP-dependent protein kinase

The insulin-like effects of vanadiumin vivo are likely to be achieved at micromolar concentrations. Demonstrated effects of vanadium on adipose tissue of streptozotocin-diabetic rats include inhibition of basal and stimulated rates of lipolysis and effects on fat cell protein phosphorylation. The studies described below examined the effects of vanadium (to a maximum concentration of 0.5 mM) on adipose cells or tissuein vitro. Vanadium, added as a vanadyl-albumin complex or as sodium orthovanadate, produced a marked (greater than 50%) inhibition of isoproterenol-stimulated lipolysis. Inhibition of lipolysis equivalent to that seen with insulin, was achieved with 100 M vanadium. In contrast, no insulin-like stimulation ofde novo fatty acid biosynthesis was observed with vanadium below 0.5 mM. Surprisingly, the antilipolytic effects of vanadium persisted in the presence of cilostamide, an inhibitor of the insulin-sensitive isoform of cyclic nucleotide phosphodiesterase. Studies with purified preparations of the catalytic subunit of cyclic AMP-dependent protein kinase revealed dose-dependent inhibition with vanadyl-glutathione (to a maximum of 40% inhibition). Equivalent inhibition of cyclic AMP-dependent phosphorylation of Kemptide (50%) was observed upon incubation of freshly-prepared fat-pad supernatant fractions with vanadyl-glutathione. These results suggest that effects of low concentrations of vanadium may be mediated, at least in part, by actions on the catalytic subunit of cyclic AMP-dependent protein kinase.     

中国中生代晚期蛇蛉化石研究（蛇蛉目：巴依萨蛇蛉科,中蛇蛉科,异蛇蛉科）

本文根据最新采获的保存完好的蛇蛉化石,对中国古生代晚期蛇蛉化石巴依萨蛇蛉科,中蛇蛉科和异蛇蛉科的有关属种的构造特征,分类位置和异我进行新的补充和厘定,建立４个新属：野蛇蛉属Ｒｕｄｉｒａｐｈｉｄｉａ ｇｅｎ。ｎｏｖ,小蛇蛉属Ｍｉｏｒａｐｈｉｄｉａ ｇｅｎ。ｎｏｖ。普蛇蛉属Ｘｙｎｏｒａｐｈｉｄｉａ ｇｅｎ。ｎｏｖ。丽蛇蛉属Ｃａｌｏｒａｐｈｉｄｉａ ｇｅｎ,ｎｏｖ;７个新种;美脉巴依萨蛇蛉Ｂａｉｓｓｏｐ     

Genetic Analysis of Parasitism in the Soybean Cyst Nematode Heterodera Glycines

A genetic analysis of parasitic ability in the soybean cyst nematode Heterodera glycines was performed. To identify and characterize genes involved in parasitism, we developed three highly inbred H. glycines lines, OP20, OP25 and OP50, for use as parents for controlled crosses. Through these crosses, we have identified genes in the inbred parents that control reproduction of the nematode on hosts that carry resistance genes. These genes, designated as ror-* for reproduction on a resistant host, segregate in a normal Mendelian fashion as independent loci. Host range tests of F(1) generation progeny indicated that at least one parasitism gene in both the OP20 and OP50 lines for host PI 88788 was dominant. Parasitism genes in OP50 for hosts ``Peking' and PI 90763 are recessive. Two types of single female descent populations, a single backcrossed BC(1)F(2)-derived and a double backcrossed BC(2)F(1)-derived, were established on the susceptible soybean cultivar ``Lee 68.' Host range tests for parasitism in these lines demonstrated the presence of two independent genes in OP50, one for host PI 88788 designated ror-1 and one for host PI 90763 designated ror-2. OP20 carries two independent genes for parasitism on PI 88788, designated as alleles kr3 and kr4.