三七中达马烷型皂甙的热不稳定性及酸水解产物

前人已证明人参和三七中富含的达马烷型人参皂甙在通常酸性水解下甙元即发生变化,而在弱酸(如50％醋酸,0.1N盐酸)条件下则形成次级皂甙。本文报道人参甙(ginseno-sides)和三七甙(notoginsenosides)的水溶液在水浴上加热亦分别形成相应的C-20位去糖基的次级皂甙。联系到人参和三七均有在蒸煮加工后C-20位去糖基皂甙收率增大的趋势,似可认为人参和三七中的这类皂甙有相当一部分是在生药的加工泡制以及提取过程中形成的次级皂甙,而不一定是植物体的原生成分。将人参甙Rb_1单体以酸水解,不仅得到主产物人参二醇(3),还分离到异去氢原人参二醇(5)、达马烷-20(22)-烯-3β,12β,26-三醇(6)、20(R)-达马烷-3β,12β,20,25-四醇(7)以及20(S)-和20(R)-原人参二醇(1、2)的混合物,从而认为这些微量成分与人参二醇一样均为达马烷型人参皂甙在酸性水解条件下C-20位糖基断裂后由真甙元的侧链转化形成的工作产物。     

The hemolymph coagulation system in invertebrate animals

A hemocyte lysate from horseshoe crab produced a gel, when exposed to Gram-negative bacterial endotoxins. This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1 3)--d-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, factor G and anti-LPS factor, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. Among these components, the complete amino acid sequences of coagulogens isolated from one American and three Asian species of horseshoe crabs have been established. Moreover, the reconstitution experiment using the isolated clotting factors, C, B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin get. Based on these results, we propose here a mechanism for the Limulus coagulation cascade.     

Immunohistochemical localization of neuropeptide Y in the guinea pig medulla oblongata

Summary The immunohistochemical localization of neuropeptide Y (NPY) was correlated with those of dopamine--hydroxylase (DBH) and vasoactive intestinal polypeptide (VIP) by mapping serial 7 m paraffin sections at three levels of the guina pig lower brainstem: a) area postrema, b) dorsal motor nucleus of the vagus, and c) nucleus prepositus of the hypoglossal nerve. Based on differences in transmitter expression, three populations of NPY-immunoreactive (IR) neurons were distinguished: NPY-IR catecholaminergic cells (NPY/CA), NPY-IR VIP-ergic cells (NPY/VIP), and NPY-IR cells which were not reactive to either DBH or VIP. Within these populations, size differences among neurons in characteristic locations allowed differentiation among the following subpopulations: NPY/CA neurons in the lateral reticular nucleus — magnocellular part (mean neuronal size 538 m²) and parvocellular part (318 m²)-, in the vagus-solitarius complex (433 m²), and in the dorsal strip (348 m²); NPY/VIP neurons in the vagus-solitarius complex (368 m²) and in the nucleus ovalis (236 m²). Apart from scattered NPY-IR cell bodies in the regions listed above, NPY-IR cell bodies in the lateral portion of the nucleus solitarius and in the caudal part of the spinal nucleus of the trigeminal nerve did not exhibit IR to either DBH or VIP. NPY-IR neurons in the area postrema occurred too infrequently for co-localization studies. The differential distribution of heterogeneous NPY-IR cell subpopulations may reflect the involvement of NPY in a variety of neuronal functions.Supported by the Deutsche Forschungsgemeinschaft, grant He 919/6-1     

Synthesis of ribonucleic acid in normal bone in vitro

1. The incorporation of [2-(14)C]uridine into nucleic acids of bone cells was studied in rat and pig trabecular-bone fragments surviving in vitro. 2. The rapid uptake of uridine into trichloroacetic acid-soluble material, and its subsequent incorporation into a crude nucleic acid fraction of bone or purified RNA extracted from isolated bone cells, was proportional to uridine concentration in the incubation medium over a range 0.5-20.0mum. 3. During continued exposure to radioactive uridine, bulk RNA became labelled in a curvilinear fashion. Radioactivity rapidly entered nuclear RNA, which approached its maximum specific activity by 2hr. of incubation; cytoplasmic RNA, and particularly microsomal RNA, was more slowly labelled. The kinetics of labelling and rapid decline of the nuclear/microsomal specific activity ratio were consistent with a precursor-product relationship. 4. Bulk RNA preparations were resolved by zonal centrifugation in sucrose density gradients into components with approximate sedimentation coefficients 28s, 18s and 4s. 5. Rapidly labelled RNA, predominantly nuclear in location, demonstrated a polydisperse sedimentation pattern that did not conform to the major types of stable cellular RNA. Material of highest specific activity, sedimenting in the 4-18s region and insoluble in 10% (w/v) sodium chloride, rapidly achieved its maximum activity during continued exposure to radioactive precursor and decayed equally rapidly during ;chase' incubation, exhibiting an average half-life of 4.3hr. 6. Ribosomal 28s and 18s RNA were of lower specific activity, which increased linearly for at least 6hr. in the continued presence of radioactive uridine. There was persistent but variable incorporation into ribosomal RNA during ;chase' incubation despite rapid decline in total radioactivity of the acid-soluble pool containing RNA precursors.     

Acid hydrolases of the rat uterus in relation to pregnancy, post-partum involution and collagen breakdown

1. The rat uterus contains acid cathepsin, beta-glucuronidase, beta-galactosidase, acid phosphatase and deoxyribonuclease II at concentrations comparable with those found in liver. Two non-hydrolytic uterine enzymes, cytochrome c oxidase and aspartate aminotransferase, display only 2-6% of the activity found in liver. 2. The concentrations of acid cathepsin and beta-glucuronidase are significantly decreased in pregnancy and increase 3-4-fold during post-partum involution. 3. The concentrations of beta-galactosidase and acid phosphatase are not decreased in pregnancy and increase only 2-3-fold during involution. 4. The concentrations of these four acid hydrolases increase linearly during the first 4 days post partum and reach their peak values at the same time that wet weight and collagen content fall to their lowest point. 5. The concentration of deoxyribonuclease is depressed in pregnancy but does not rise above normal in the post-partum period. 6. Only a small proportion of each hydrolytic activity can be isolated in the mitochondrial-lysosomal fraction of sucrose homogenates of the rat uterus. This proportion increases during involution. However, the extensive mitochondrial rupture occurring during homogenization indicates that the technique is probably too harsh to obtain a true measure of the proportion of lysosomes present in the intact tissue. 7. There are no significant changes in either the concentration or subcellular distribution of the five acid hydrolases in the livers of the experimental rats during pregnancy or involution. In each case the largest proportion of the activity is found in the mitochondrial-lysosomal fraction of liver homogenates. 8. The results are interpreted in terms of the lysosomal theory of intracellular digestion.     

牛生长激素结构不均一性的研究

本文报导用常规方法分离纯化的牛生长激素,在还原性SDS-11％聚丙烯酰胺凝胶电泳中呈分子量很接近的两条主带(22KD,21.5KD)。用单克隆抗体和多克隆抗体亲和层析技术分析了不同分子量形式的牛生长激素的转化,结果表明:牛生长激素可能在pH5.5条件下转化为21.5KD分子,在pH8.3条件下则转化18KD分子。这几种形式的牛生长激素均保留与抗体的结合力,但亲和力不尽相同,如在亲和层析的洗脱性质上存在差异。已检验分离并部分纯化了18KD分子以备作进一步的研究。     

Release of erythrocytes from the spleen during exercise and splenic constriction by adrenaline infusion in the rainbow trout

Erythrocyte-supplying function of the spleen was examined in the rainbow troutSalmo gairdneri under exercise. The spleen showed remarkable reduction, about 70% in weight and about 85% in hemoglobin content, after forced exercise of 15 min. The amount of erythrocytes released from the spleen was 2.33 ml/kg body, and this amount corresponds to about 20% of the total volume of circulating erythrocytes in resting condition. No damage was observed at the spleen, splenic artery and splenic vein after the exercise. Examination of the vascular system by a corrosion casting method showed that no place other than the venous circulation exists for the erythrocytes released from the contracted spleen. The spleen was strongly constricted by infusion of adrenaline into the organ. These facts imply that the fish spleen supplies stored hemoglobin into the circulating blood in response to an increased demand of oxygen during exercise, under the control of the sympathetic nervous system.     

倭竹属地理分布的研究

倭竹属Shibataea Makino隶于禾本科之竹亚科,现已知有8种,分布于我国东南部的浙江、福建、江苏、安徽、江西等省,广东、台湾两省有少量栽培,日本产1种。苏联、西德、印尼等国所栽培的倭竹均系自我国或日本引入。我国浙-闽地区产8种,且都有野生发现,是本属的现代分布中心。倭竹属植物体型矮小,常植于庭院或公园中供观赏。近年来盆景艺术迅速发展,微型园林日益兴起,倭竹属植物体态优美,常绿,耐寒且易于栽培,为广大园林工作者所垂青。     

安徽烟草病毒类型及优势种初步研究

1978年,烟草病毒病在安徽烟区流行,导致凤阳县烟叶总产损失92.3％,引起了普遍震惊。1981—1984年作者对来自16个县、市552个病毒材料,经生物测定、血清反应、电镜观察,初步分离出CMV、TMV、PVY和PVX四种病毒。它们分别约占检测总数的82.79％、4.53％、2.54％和0.36％,其中CMV与长期视为优势种的TMV比值为18.3,除此,尚有约占检测总数9.8％的CMV和TMV、CMV和PVY复合侵染,以及不明类型的毒株。通过对田间烟草以及其他植物花叶病株的实际检测,进一步表明:CMV在烟区分布范围极广、出现频次最多,已形成了复杂的循环侵染系统,成为近期内烟草病毒病持续流行危害的首要毒原。     

高胆固醇高脂肪膳食对家兔β-VLDL组成及其与巨噬细胞相互作用的影响的初步研究

给家兔喂以1％胆固醇及10％菜油(A组)或猪油(B组)50多天后A组血胆固醇水平(824.2±265.1mg/dl)明显低于B组(1666±693.8mg/dl);A组甘油三酯水平(51.9±19.1mg/dl)亦低于B组(104±40.2mg/dl)。二组家兔的β—VLDL的脂类组成无差别,但A组β—VLDL的apoE高于B组,分别为45.2％及37.5％。高分子量apoB(apoB_h)为33.6％,低于B组β-VLDL(47.3％)。A组β-VLDL促进小鼠腹腔巨噬细胞胆固醇堆积的程度大于B组,可能与apoE含量高有关。我们认为多不饱和脂酸减轻动脉粥样硬化(As)的作用不在于改变脂蛋白构成后阻碍泡沫细胞的形成而是促进β—VLDL从体内清除。