Cloning of novel conotoxin precursor sequences from Conus pulicarius

Conotoxins are small peptides in the venoms of Conus genus with various physiological activities targeting ion channels and receptors in the neuromuscular system. Applying a modified 3'-RACE (Rapid Amplification of cDNA Ends) strategy, two novel precursor cDNA sequences were cloned from a small vermivorous cone snail, Conus pulicarius. The predicted mature peptides were named conotoxin PuIA, and PuIIA respectively. Conotoxin PuIA consists of 30 residues of amino acids and conotoxin PuIIA 28. Both the two conotoxins have the same cysteine framework and are believed to be members of the O-superfamily conotoxins.     

Effect of New O-Superfamily Conotoxin on Voltage-Activated Currents of Hippocampal Neurons

The effects of a new O-superfamily conotoxin, SO3, on sodium current (INa), transient A-type potassium currents (IA), and delayed rectified potassium currents (IK), were examined in cultured rat hippocampal neurons using the whole-cell patch clamp technique. Addition of SO3 caused a concentration-dependent, rapidly developing, and reversible inhibition of voltage-activated currents. The IC50 values for the blockage of INa, IA, and IK were calculated as 0.49, 33.9, and 7.6 μmol/L, respectively. The determined Hill coefficients were 1.7, 0.6, and 1.2, respectively. These results indicate that SO3 can selectively inhibit neuronal sodium and potassium currents.     

Molecular characterization of a K+ channel blocker in the scorpionButhus martensii Karsch

K⁺ channel blockers of scorpion venoms are of important value in studying pharmacology and physiology of specific K⁺ channel of cells. Based on the amino acid sequences of BmP01 previously characterized as a small-conductance Ca²⁺-activated K⁺ channel blocker, two “back to back” degenarate primers have been designed and synthesized for inverse PCR strategy, its full-length cDNA has been cloned from the venom gland of the Chinese scorpionButhus martensii. The cDNA is composed of 3 parts: 5′ UTR, ORF and 3′ UTR. The flanking sequence of translation initiation codon ATG is AAAATGA, which is highly conserved in scorpion Na⁺ channel toxin and protozoan genes, suggesting that these genes may have followed a common mechanism for translation initiation. The 3′ UTR contains poly(A) signal AATAAA. The open reading frame encodes a precursor of 57 residues with a signal peptide of 28 residues and a mature peptide of 29 residues. The signal peptide is rich in hydrophobic amino acid residues and its length is significantly different from that of the determined scorpion Na⁺ channel toxin. The deduced amino acid sequence of mature peptide is completely consistent with BmP01 previously determined by primary structure analysis.     

Embryonic development and organogenesis of Chinese giant salamander, Andrias davidianus

The morphology and organogenesis of Chinese giant salamander, Andrias davidianus, in its different developmental periods and stages are described in detail, which provides an intact criterion for distinguishing different stages of its developmental process. Based on the external morphological and internal histological features, six periods including 20 stages of organogenesis of Chinese giant salamander are established, which are cleavage period, blastula period, gastrula period, neurula period, organogenesis stage and hatching stage. Generally, the embryonic development of Chinese giant salamander is consistent with those of Eastern newt, Cynops orientalis, and Black spots frog, R. nigromaculata. However, they have some differences in the early cleavage process and the development of digestive system. The cleavage of Chinese giant salamander, A. davidianus is not a discoidal division type, which is different from other species reported. And the first three cleavages being meridional and a retardant development of its digestive system without halter and sucker existing are the evident features of the embryonic development of Chinese giant salamander.     

不同种植模式对香榧生长及水土保持的影响

香榧是我国特有干果树种,常以香榧-中药材复合种植模式开展经营作业。通过测定香榧-艾蒿、香榧-黄精、香榧-前胡、香榧-掌叶覆盆子的林药复合种植模式的香榧生长变化指标及土壤含水量变化特征,探究香榧生长最佳、水土保持能力最优的香榧-中药材复合种植模式,为香榧复合种植不同中药材的合理性提供借鉴。研究结果表明：香榧-艾蒿、香榧-黄精是香榧树干基径增长率最高的2种模式。不同复合种植模式、不同坡位与不同的复合种植模式的中介效应可以联合解释83.4%的林下土壤含水量变化。香榧-艾蒿复合种植模式下的香榧生长情况较好、水土保持效果最佳,开展香榧经济林的林药模式复合经营时,可以考虑采用艾蒿作为药材植物。     

威灵仙水提物对卵形鲳鲹源溶藻弧菌的抑制作用

近年来水产养殖行业不断扩大,但随之而来的鱼病对养殖行业造成了巨大损失.本研究以卵形鲳鲹(前期发病)上分离出的溶藻弧菌为实验对象,批量筛选多种中草药,选择抑菌效果最好的一种或几种中草药,并探究不同浓度中草药水提物的抑菌效果,确定其杀菌浓度(MBC)及最小抑菌浓度(MIC),再通过生化指标胞内乳酸脱氢酶(Lactate d...     

我国海洋生物废弃物药用研究现状与策略

《神农本草经》《本草纲目》均有以海洋生物废弃物作中药应用的记载,用药历史悠久,现代研究同样证实海洋生物废弃物中药营养价值丰富,有巨大的药用潜力.加之我国海洋生物物种繁多,每年产生的海洋生物废弃物数量庞大,不利于海洋环境保护,因此,可采用现代科技有效利用海洋生物废弃物,发挥其药用价值.本文综述《神农本草经》《本草纲目》中...     

中国海背肛虫属Notopygos(多毛纲,仙虫科)两新纪录种

记述了中国海背肛虫属Notopygos仙虫科Amphinomidae两新纪录种——厚唇背肛虫Notopygos labiatus McIntosh,1885和安氏背肛虫Notopygos andrewsi Monro,1924。前者在中越北部湾海洋综合调查(1959~1962年)时,采集于广西北部湾潮下带;后者在全国海洋综合调查(1958~1960年)时,采集于西沙群岛潮间带。标本均保存在中国科学院海洋研究所海洋生物标本馆。本文对两新种的外部形态特征进行了仔细观察并描记。     

基于CiteSpace软件的绞股蓝研究文献可视化分析

目的 分析绞股蓝的研究现状,以发现其研究热点及变化趋势,为今后研究提供参考。方法 检索中国知网（CNKI）、万方、维普、中国生物医学文献数据库和Web of science中1991年1月1日至2021年12月31日绞股蓝的相关文献,采用CiteSpace.5.7.R5软件对文献作者、研究机构、关键词等内容构建知识图谱的可视化分析。结果 共筛选纳入中文文献2491篇、英文文献510篇。中、英文文献发文量总体呈波浪式上升趋势;研究机构和作者的共现知识图谱显示,研究机构和作者主要集中在各大高校和科研院所;论文发文量最多的作者分别是谭华炳和朴香兰;发文量最多的机构是吉首大学生物资源与环境科学学院和中国科学院,各研究机构间合作较少;高频关键词知识图谱显示“绞股蓝总皂苷”、“绞股蓝皂苷”、“绞股蓝多糖”关键词中心性排在前3位。中英文文献分析显示绞股蓝的研究主要集中在药理作用和临床实验等方面,成分分析、药效物质作用机制、临床应用、开发利用是今后的研究热点。结论 目前绞股蓝的研究仍处于发展阶段,科学合作网络分布松散,未来作者、研究机构之间需跨团体、跨区域增强团队间交流合作,为进一步研究提供借鉴。     

基于数据挖掘分析含青蒿方剂的配伍规律及应用特点

目的 基于数据挖掘技术探讨青蒿配伍规律及应用特点,为临床使用中药青蒿提供参考依据。方法 以国家人口与健康科学数据共享平台收录的含青蒿中药方剂为数据来源建立青蒿方剂数据库,利用MicrosoftOffice Excel 2021、IBM SPSS Modeler 18.0、IBM SPSS Statistics 23.0等软件对纳入方剂进行分析,使用Cytoscape3.7.2软件构建网络可视图。结果 最终纳入含青蒿的中药方剂50首,主治疾病为发热。涉及的189味中药累计使用564次,性多寒、温,味辛、苦,归肝经、肺经为主,功效分类上以清热药、补虚药、解表药最为常见。高频中药关联规则分析显示,药对组合中青蒿-柴胡,青蒿-黄芩的支持度较高;三味药组中青蒿-黄芩-柴胡的支持度最高。治疗发热时,青蒿常与柴胡、黄芩、金银花等中药配伍,高频中药关联规则45项,聚类分析得到5类治疗发热的基本药物组合。结论 本研究分析总结了含青蒿中药方剂的主治病证、配伍规律及应用特点,为临床科学规范使用青蒿提供了参考。     

H-ATPase in the plasma membrane of Arabidopsis pollen cells is involved in extracellular calmodulin-promoted pollen germination

In this paper, the role of the plasma membrane (PM) H⁺-ATPase in extracellular calmodulin (CaM)-promoted pollen germination and in tube growth of Arabidopsis thaliana was investigated. Pollen germination, pollen tube growth rate, free cytosolic Ca²⁺ concentration ([Ca²⁺]_cyt) and Ca²⁺ channel activity in the PM of pollen cells were measured. In response to fusicoccin or CaM treatment, in vitro pollen germination and pollen tube growth rate, [Ca²⁺]_cyt and activity of a hyperpolarization-activated Ca²⁺-permeable channel increased. Sodium vanadate inhibited the promotion of these parameters by extracellular CaM. The results suggest that H⁺-ATPase may be involved in extracellular CaM-regulated pollen germination and in tube growth by modulation of the hyperpolarization-activated Ca²⁺ channel in the PM of A. thaliana pollen cells.     

Reporter-based screen for <Emphasis Type="Italic">Arabidopsis</Emphasis> mutants compromised in nonhost resistance

Plants are exposed to many potentially pathogenic microbes in the environment, but each species is only susceptible to a limited number of pathogens. The broad resistance is referred to as nonhost resistance. To date, little is known about the underlying mechanism of nonhost resistance and the signaling transduction process. Here we describe a simple method for isolating Arabidopsis nonhost resistance mutants against a nonadapted bacterial pathogen. A RAP2.6 promoter-driven LUC reporter system was developed to replace the tedious bacterial growth assay during the primary screening. The RAP2.6-LUC reporter gene is normally induced by the virulent bacterium Pseudomonas syringae pv tomato but not the nonadapted bacterium P. syringae pv phaseolicola. By using this method we iso- lated 4 mutants displaying strong reporter activity in response to P. syringae pv phaseolicola, which were characterized in some details, ebsl, ebs2, ebs3, and ebs4 （enhanced bacterial susceptibility） were compromised in resistance against P. syringae pv phaseolicola and/or P. syringae pv tomato. In addition, ebs4 showed enhanced hypersensitive response to the incompatible bacterium P. syringae pv tomato （avrB）. These results demonstrated that the method is suited for large scale screening for nonhost resistance mutants.     

Modulation of low-frequency oscillations in GaAs MESFETs’ channel current by sidegating bias

Low-frequency oscillations in channel current are usually observed when measuring the GaAs MESFET‘s output characteristics. This paper studies the oscillations by testing the MESFET‘s output characteristics under different sidegate bias conditions. It is shown that the low-frequency oscillations of channel current are directly related to the sidegate bias. In other words, the sidegate bias can modulate the oscillations. Whether the sidegate bias varies positively or negatively, there will inevitably be a threshold voltage after which the low-frequency oscillations disappear. The observation is strongly dependent upon the peculiarities of channel-substrate (C-S) junction and impact ionization of traps-EL2 under high field. This conclusion is of particular pertinence to the design of low-noise GaAs IC‘s.     

Genetic study on the behavior of honeybees influenced by polyandry system

Within a honeybee population, due to polyandry, there are supersister and halfsister relations, thus many subfamilies exist. For the Chinese honeybee (Apis cerana cerana F.) a phylogenetic dendrogram has been constructed in which 4 subfamilies are clustered based on DNA fingerprint patterns. And it has been observed that each kind of workers is distributed to several dierent sub-families.     

黄连水提物对卵形鲳鲹源溶藻弧菌的抑菌作用

卵形鲳鲹(Trachinotus ovatus)是一种生长快速且肉质鲜美的经济型海水养殖鱼类,但是近些年为满足人们的日常需求,在不断扩大养殖的同时病菌也逐渐泛滥。溶藻弧菌(Vibrio alginolyticus)是华南沿海地区海水养殖鱼类细菌性鱼病的主要致病菌之一,给水产养殖业带来巨大损失。本研究对黄连(Coptis chinensis Franch)的抗菌作用进行系统研究,目的是为由溶藻弧菌引起的爆发性细菌性鱼病的高效防治提供科学的用药依据。本研究采用二倍稀释法测定黄连水提物对卵形鲳鲹源溶藻弧菌的最低抑菌浓度(MIC)、最低杀菌浓度(MBC)和半数致死量(LD50),并使用BCA蛋白浓度测定试剂盒测定细菌超声破碎上清液中可溶性蛋白含量。结果表明,黄连水提物对溶藻弧菌具有明显的抑制作用,其对溶藻弧菌的MIC、MBC和LD50的值分别为7.800mg/mL、31.250mg/mL和15.625mg/mL。胞内可溶性蛋白含量变化的结果提示:黄连发挥抑菌作用的机制可能是通过损伤细菌的细胞壁导致细菌内容物的释放并引起菌体裂解死亡。黄连具有发展成为一种高效抗水产病害中草药制剂的潜力。     

鳞尾木的食用和药用价值及开发现状

鳞尾木(Lepionurus sylvestris Bl.)是主产于云南东南部与广西西南部河谷密林或石缝间隙中的一种稀有木本野菜,其嫩茎作为当地的一种美味野生菜肴,具有丰富的营养成分和特殊的药用价值,但其资源稀少,人为破坏严重,自然栽培困难,势必会引起一场开发热潮。本文简述了鳞尾木的形态学特征、分布地、营养成分研究、活性成分研究等,并结合野菜的营养、药用价值,分析总结出鳞尾木拥有极高的开发前景,为中国原料药的研究生产和鳞尾木的合理开发提供科学的参考依据。     

The internal structure of Early Cambrian fossil embryo <Emphasis Type="Italic">Olivooides</Emphasis> revealed in the light of Synchrotron X-ray Tomographic Microscopy

Countless fossil embryo Olivooides and the hatched larvae, juveniles and adults （the latter two kinds are Punctatus） are recovered by means of acid maceration from the fine-crystalline to medium-crystalline phosphatic limestone and phosphatic micrite of Early Cambrian Kuanchuanpu Formation at the Shizhonggou section, near Kuanchuanpu Village, Ningqiang County, Shaanxi Province, China. Using the technique of Synchrotron X-ray Tomographic Microscopy, the 3D internal structure of Ofivooides and Punctatus is reconstructed. The morphological and statistic analyses are also given to the stellae structure of Ofivooides and Punctatus, which indicates that this structure is a result of adaptive evolution to a lifestyle of fast-attaching after hatching, probably with the function of mucilage secretion. The internal structure of Punctatus is described and discussed. The ovum-like structure, a common internal feature of Punctatus, is considered as the taphonomic structure, rather than eggs or other biological structure. This structure is thought to be formed after the burial of the animal and before or during the mineralization. The original internal structure of Punctatus is assumed to be tabulae-filled, with soft body grown on them.     

《中国药典》中四个品种来源的陈皮挥发油GC-MS分析比较

目的采用主成分分析(PCA)和聚类分析对《中国药典》中四个品种来源的陈皮挥发油GC-MS数据分析比较,鉴别其不同种源。方法对80批次不同品种和不同产地的陈皮样品挥发油进行GC-MS分析,利用其共有成分峰面积数据,采用主成分分析和聚类分析将共有特征峰进行鉴别区分。结果通过主成分分析和聚类分析可将广东新会茶枝柑样品与其它地区样品大致分为两类。结论本方法可用于新会陈皮和其它不同品种来源陈皮的鉴别。     

不结球白菜种质创新及资源信息管理研究进展

对不结球白菜(Brassica campestris ssp. chinensis Makino)抗性育种、细胞质雄性不育、基因克隆和转基因育种、遗传图谱和DNA分子标记辅助育种,以及种质资源信息管理进行了综述,以期为不结球白菜种质创新和管理提供参考和建议.     

吉安新引进铁皮石斛品种农艺性状及总多糖含量分析

通过比较分析新引进铁皮石斛的农艺性状和石斛总多糖含量的变化,为吉安引进优良铁皮石斛品种"雁吹雪3号"提供理论依据.研究结果表明:3月至5月期间为铁皮石斛生长旺盛时期,"雁吹雪3号"的株高、茎粗、顶叶长和宽等农艺性状,以及干鲜重、石斛总多糖含量均高于吉安主栽品种仙斛1号,采收最佳时间为第3年的5月开花之前.雁吹雪3号三年...