土牛膝碱（abidenine）的分离及结构测定

从土牛膝(Achyranthes bidentata Bl.)的根中分离到一种新的生物碱——土牛膝碱(abidenine)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）。     

土牛膝抗炎成分分离、鉴定与含量测定研究

本研究建立脂多糖诱导的巨噬细胞炎症模型,结合层析法对土牛膝抗炎活性成分进行分离,并用NMR、MS以及与对照品比较,对得到的化合物进行结构鉴定。结果表明粗毛牛膝醇提取物抗炎效果最佳,其反相层析50%、70%及100%甲醇洗脱物抗炎活性高和细胞毒性低,从50%～70%甲醇洗脱物分离鉴定出9种单体化合物:β-蜕皮甾酮(1)、牛膝甾酮(2)、水龙骨甾酮B(3)、N-反式阿魏酰酪胺(4)、N-顺式阿魏酰酪胺(5)、N-顺式阿魏酰-3-甲氧基酪胺(6)、N-反式阿魏酰-3-甲氧基酪胺(7)、竹节参皂苷Ⅳa(8)、5,2′-二甲氧基-6-甲氧甲基-7-羟基-异黄酮(10);100%甲醇洗脱物鉴定出主要成分竹节参皂苷Ⅰ(9)。在LPS+25μM单体浓度下,化合物抗炎活性由强到弱为41526910378。反相液相色谱测定结果表明,野生牛膝和柳叶牛膝(两年生)地下根茎β-蜕皮甾酮含量在温度高季节含量高,8月份达到最高,分别为0.914±0.016和1.412±0.038 mg/g;两年生粗毛牛膝随季节变化规律不明显。具有抗炎活性的阿魏酰酪胺类生物碱首次从土牛膝中分离鉴定。     

三株解烃菌的分离鉴定和菌种保藏

我们从油田土样中分离得到三株解烃菌。它们是C20—11能利用樟脑,D36—3能利用十六烷,T3能利用苯甲酸和萘。菌株经鉴定,C20—11为粪产碱菌(Alcaligenes faecalls),D36—3为节杆菌(Arthrobacter sp.),T_3为乙酸钙不动杆菌(Acinetobacter calcaceticus)。     

中国单轴霉分类的研究——Ⅰ.寄生在唇形科和苋科植物上的新种

本文描述了单轴霉属(Plasmopara)霜霉菌的二个新种。它们是:寄生于唇形科植物香薷(Elsholtzia ciliata(Thunb.)Hyland)上的香薷单轴霉(Plasmopara elsholtziae spnov.)及苋科植物牛膝(Achyranthes bidentata Bl.)上的牛膝单轴霉(Plasmopara achyranthis sp. nov.)。牛膝单轴霉是本属真菌寄生于苋科植物的首次记录。上述二新种都有拉丁文及汉文描述,还分别讨论了新种与其同科或不同科寄主上的近似种之间的区别。     

乳突拟耧斗菜中的一新二萜成分

从乳突拟耧斗菜(Paraquilegia anemoides)乙醇提取物的非碱部分中分得两个二萜类化合物:ent—考兰烷—16β,17—二醇和拟耧斗菜素(paraquilegin)。其中拟耧斗菜素是一新化合物,其结构经光谱解析和化学方法证明为ent—17—咖啡酰氧基-考兰烷—16B-醇。     

中国单轴霉分类的研究*I．寄生在唇形科和苋科植物上的新种

本文描述了单轴霉属(Hasmopara)霜霉菌的二个新种。它们是： 寄生于唇形科植物香薷(Elsholtzia ciliata (Thunb．)Hyland)上的香薷单轴霉(Plasmopara elsholtziae sp.Nov．)及苋科植物牛膝(Achyranthcs bidentata BI．)上的牛膝单轴霉(Plasmopara achyranthis sp．nov．)。牛膝单轴霉是本属真菌寄生于苋科植物的首次记录。 上述二新种都有拉丁文及汉文描述,还分别讨论了新种与其同科或不同科寄主上的近似种之间的区别。     

东北地区草本植物1个新记录科和3个新记录属

东北地区位于我国东北部,共有维管束植物164科928属3 103种。根据野外调查结果及相关资料,报道了东北地区草本植物1个新记录科—粟米草科(Molluginaceae)和3个新记录属—粟米草属(Mollugo L.)、牛膝属(Achyranthes L.)和秃疮花属(Dicranostigma Hook. f. et Thoms.),以及对应的3个新纪录种—粟米草(Mollugo stricta L.)、牛膝(Achyranthes bidentata Blume)和秃疮花[Dicranostigma leptopodum(Maxim.) Fedde]。新记录种凭证标本保存于大连自然博物馆植物标本室。这些新记录草本植物的发现,对东北地区生物多样性的研究具有重要意义,为其在我国的地理分布研究提供了新资料。     

培养基质、储藏方式和盐度对三种海滨植物种子萌发的影响

研究了培养基质、储藏方式和盐度对3种海滨植物互花米草(Spartina alterniflora)、盐地碱蓬(Suaeda salsa)和芦苇(Phragmites australis)种子萌发的影响,探索在潮间带环境下海滨植物种子萌发适应策略。结果表明:3种植物的干藏种子和湿藏芦苇种子随着盐度的升高,萌发率和萌发速率均显著下降,湿藏互花米草和盐地碱蓬种子在各盐度下萌发率和萌发速率差异不显著。各盐度-土培-干藏互花米草,中、高盐度-土培-干藏盐地碱蓬,土培各处理,中、高盐度-水培-干藏,高盐度-水培-湿藏芦苇种子萌发失败。湿藏提高了各盐度处理下土培互花米草,中、高盐度-水培和土培盐地碱蓬,淡水、中盐度-水培芦苇种子的萌发率和萌发速率。干藏互花米草种子在中、高盐度和土埋条件下种子的萌发受到抑制,限制了互花米草向高潮带与潮上带的扩展;而经常受潮水浸淹保持湿润的种子能抵抗高盐和泥沙沉积,导致互花米草种群逐步向低潮带方向发展;湿藏芦苇种子在淡水中萌发率和萌发速率最高,当潮上带盐度降低时,芦苇具有很强的竞争优势,但是对盐度和土埋敏感,限制了其向海的拓展;盐地碱蓬在中、高盐度和土培条件下萌发速率最高,快速萌发的适应策略和广适应性在盐地碱蓬占据高潮带和中潮带广大区域的过程中起到了重要的作用。     

入侵植物马缨丹(Lantana camara)及其伴生种的光合特性

马缨丹(Lantana camara L.)是粤东地区的入侵植物之一.采用LI-6400光合作用仪对马缨丹及其常见主要伴生种鬼针草(Bidens pilosa L.)、肖梵天花(Urena lobata L.)、土牛膝(Achyranthes aspera L.)在不同有效光合辐射(PAR)和不同CO2浓度下的光合生理指标进行测定,结果表明:(1)马缨丹的光饱和点(LSP)与光补偿点(LCP)分别为1225、13.58 μmol·m-2·s-1,均低于伴生种,且和伴生种差异达到显著水平,光饱和点时的最大净光合速率(Pmax)为13.89μmol·m-2·s-1,表观量子效率(AQY)为0 0503 μmol·m-2·s-1,与土牛膝相当,而显著高于肖梵天花;(2) 马缨丹的CO2饱和点(CSP)与CO2补偿点(CCP)分别为1350、61.78 μmol·mol -1,CO2饱和点时马缨丹的最大净光合速率(Pmax)为20.08 μmol·mol-1,显著高于土牛膝,马缨丹的表观羧化效率(CE)与鬼针草相当,为0.0424 μmol·mol -1;(3)有效光合辐射与CO2浓度的增加,对马缨丹气孔导度(Gs)、蒸腾速率(Tr)影响不明显,但大大提高了其水分利用率(WUE),提示马缨丹对于环境中光强和CO2的变化具有良好的适应能力.这些信息对马缨丹生理生态学特性的认识是一个补充,并能为马缨丹入侵机制的研究提供一些有价值的参考.     

牛膝药理作用的研究进展

牛膝为苋科牛膝属植物牛膝(Achyranthes bidentata Blume)的干燥根,是我国的传统中药,有着悠久的历史。牛膝始载于《神农本草经》,列为上品,又名百倍,因其茎有棱角,节部膨大,形似牛膝而得此名。主产于河南黄河以北的温县、沁阳、孟县、辉县、博爱     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细