浙江吻虾虎鱼属一新种（鲈形目：虾虎鱼科）

本文描述分布于浙江省武义县武义江的一吻虾虎鱼新种,定名为武义吻虾虎鱼Rhinogobius wuyiensis。该虾虎鱼具有如下特征可区别于相近种：具备眼肩胛骨管及前鳃盖管;椎骨数10+16=26;臀鳍分支鳍条7～9（平均7.8）;颊部斑点大小不等且不规则,常呈线状交织;鳃盖条部内侧无斑点。     

福建吻虾虎鱼属一新种(鲈形目,虾虎鱼科)

描述分布于福建省福州市北峰溪流中的一吻虾虎鱼新种,定名为网纹吻虾虎鱼Rhinogobius reticulates sp.nov..该虾虎鱼与R.mekongianus和R.nammaensis在头部斑纹上相似,但具有区别于此两种吻虾虎鱼的特征:纵列鳞27～29(平均27.7);椎骨数26～27(平均26.5);成体眼肩胛骨管通常于眼窝后具有两个感觉管孔ω和ω1;鳃盖条部具8～13条红色网状条纹;眼下缘具1红棕色条纹;全身密布黑褐色细点;体侧无斑块.     

中国广东省虾虎鱼一新种——周氏吻虾虎鱼(Rhinogobius zhoui)(鲈形目:虾虎鱼科)

记述了分布于广东省海丰县莲花山溪流中的吻虾虎鱼属一新种,定名为周氏吻虾虎鱼Rhinogobius zhoui。该新种可由如下特征区别于相近种：第二背鳍条I, 8—9;臀鳍条I, 7—8;胸鳍条16—18;纵列鳞29—31;背鳍前鳞10—12;椎骨数10+16=26;成年雄性个体第一背鳍无黑斑,各奇鳍具宽大的亮白色边缘,颊部与鳃盖膜无斑纹,体侧具6—8个红色斑块。     

中国吻虾虎鱼属一新种：鲈形目：虾虎鱼科

在浙江省灵江水系上游横溪镇附近溪流中,采到１种吻虾虎鱼属鱼类,经鉴定为１新种。根据该种鱼类颊部具１－４条明显的细斜纹,定名为颊纹吻虾虎鱼Ｒｈｉｎｏｇｏｂｉｕｓ ｇｅｎａｎｅｍａｔｕｓ Ｚｈｏｎｇ ｅｔ Ｔｚｅｎｇ ｓｐ．ｎｏｖ．     

广西云南鳅属鱼类一新种记述

2003年5月,在广西壮族自治区都安县高岭乡红水河水系采集到一批条鳅标本。经鉴定,为云南鳅属(Yunnanilius)一未经发表的新种。新种长须云南鳅(Yunnanilus longibarbatus sp.nov.)属于黑斑云南鳅种组(Yunnanilus nigromaculatusgroup),并与黑斑云南鳅[Y.nigromaculatus(Regan)]、钝吻云南鳅(Y.obtusirostris Yang)、长背云南鳅(Y.longidorsalisLi,Tao et Lu)和巴江云南鳅(Y.bajingensisLi)等4种最为相似。长背云南鳅背鳍分枝鳍条11根,颌须短,仅达眼中部,背鳍起点距吻端较距尾鳍基为近,可与包括本种在内的其余4种相区别(背鳍分枝鳍条8-9根,颌须达到或超过眼后缘,背鳍起点距吻端较距尾鳍基为远)。本种和钝吻云南鳅上颌中央无齿状突、下颌中央无缺刻,可与黑斑云南鳅和巴江云南鳅相区别。本种在鳍条数、上下颌、背鳍起点的位置、尾鳍形状、鳞片、头部侧线管孔、体侧纵纹等方面与钝吻云南鳅最为相似,但本种可藉多个特征与后者相区别:颌须伸过眼后缘至鳃盖后缘的中点至鳃盖后缘,是已知云南鳅中须最长的;背鳍不分枝鳍条下1/3处具一不显著黑色斑点(vs.无斑);体侧纵纹,其宽窄于眼径,较大个体背鳍之前的纵纹被虫状纹取代(vs.体侧纵纹始终存在,其宽约等于眼径);头背具斑点(vs.无斑);尾柄较细长,体长/尾柄长=5.3-6.1(vs.7.4-9.0,尾柄长/尾柄高=1.3-1.8vs.0.8-1.1)。     

云南滇池入侵虾虎鱼类的共存策略

虾虎鱼类是入侵种的一个重要来源,常数种共同入侵同一区域,其种间如何实现共存是当前鱼类入侵生态学的一个重要科学问题。本研究通过形态分析、空间分布调查及摄食分析等方法,从形态分化和生态位分化角度揭示滇池新入侵的粘皮鯔虾虎鱼与先期入侵近缘种的共存策略。结果表明: 粘皮鯔虾虎鱼与小黄黝鱼、子陵吻虾虎鱼、波氏吻虾虎鱼等先期入侵种在形态上存在显著差异。其空间分布在研究区域上与上述物种存在显著差异,空间生态位指数显著高于其余物种。摄食分析显示,粘皮鯔虾虎鱼的食物多样性指数显著高于其余物种;其主要摄食种类为圆形盘肠溞和腺介虫等,与其他虾虎鱼类主要摄食种类也存在明显差异。在摄食生态位上,滇池入侵虾虎鱼类存在显著分化。这说明形态差异、空间生态位分化及营养生态位分化降低了种间竞争强度,促进了粘皮鯔虾虎鱼与先期入侵虾虎鱼类实现共存。粘皮鯔虾虎鱼可能凭借摄食策略上的优势在种群数量、占据栖息地范围上优于竞争对手,成为研究区域入侵虾虎鱼类中的优势种群。     

基于碳、氮稳定同位素技术研究象山港虾虎鱼类营养生态位

以象山港水域9种虾虎鱼为研究对象,利用稳定同位素技术分析虾虎鱼类的营养生态位和种间竞争关系。结果表明:所测样品δ13C值和δ15N值的变化范围分别为-20.4‰~-12.7‰和6.7‰~14.5‰,不同种类样品的δ15N值和δ13C值均存在显著差异;象山港虾虎鱼类营养层次整体较低,多数种类在该生态系统中起到次级消费者的作用;舌虾虎鱼(Glossogobius giuris)、矛尾虾虎鱼(Chaeturichthys stigmatias)和六丝钝尾虾虎鱼(Amblychaeturichthys hexanema)的营养生态位宽幅相对较大,而小头栉孔虾虎鱼(Ctenotrypauchen microcephalus)、绿斑缰虾虎鱼(Amoya chlorostigmatoides)和纹缟虾虎鱼(Tridentiger trigonocephalus)等营养生态位宽幅相对较小;象山港虾虎鱼类营养生态位重叠严重,小头栉孔虾虎鱼-孔虾虎鱼(Trypauchen vagina)、髭缟虾虎鱼(Tridentiger barbatus)-纹缟虾虎鱼等之间存在激烈的营养生态位竞争。     

诸氏鲻虾虎鱼出血病病原鉴定及传播途径分析

目的分离鉴定诸氏鲻虾虎鱼(Mugilogobius chulae)出血病病原,并探讨其传播途径,为虾虎鱼微生物质量控制提供技术依据。方法从患出血病虾虎鱼肝脏取样分离病原菌,经菌落形态、生化特性和分子特征鉴定细菌,回归感染确定其致病性,并采用双重PCR方法对虾虎鱼、轮虫、卤虫、水进行嗜水气单胞菌(Aeromonas hydrophila)检测。结果分离到1株优势菌PYMc15-1,该菌株API生化反应结果与嗜水气单胞菌一致,gry B序列与Gen Bank上的嗜水气单胞菌相应基因序列同源性最高;根据已知序列构建gry B分子系统进化树,分离株PYMc15-1与嗜水气单胞菌聚类;分离株PYMc15-1溶血素基因(hly A)和气溶素基因(aer A)检测结果阳性,对虾虎鱼半致死剂量(median lethal dose,LD_(50))为每尾1. 2×104cfu。野生虾虎鱼、卤虫和野生轮虫致病性嗜水气单胞菌检测出现阳性结果,虾虎鱼封闭群、室内培育的轮虫以及海水样品致病性嗜水气单胞菌检测均为阴性。结论嗜水气单胞菌可自然感染虾虎鱼;野生虾虎鱼和生物饵料是其潜在传播媒介,引进虾虎鱼和生物饵料时应检测该病原。     

矛尾复虾虎鱼物种命名有效性探讨

利用形态学和遗传学方法探讨斑尾复虾虎鱼和矛尾复虾虎鱼的亲缘关系及矛尾复虾虎鱼物种有效性.研究结果显示:两种虾虎鱼在量度特征上存在极显著的差异,但分节特征不存在显著差异;与斑尾复虾虎鱼相比,矛尾复虾虎鱼头长相对较小,而尾鳍相对较长.对两种虾虎鱼的线粒体DNA控制区片段序列进行比较分析,得到两种虾虎鱼的遗传距离仅为0.006,与种内距离相当;NJ和MP法构建的系统树也显示两种虾虎鱼间亲缘关系很近,两种间不存在显著差异.综上,矛尾复虾虎鱼并非有效物种,应为斑尾复虾虎鱼的同种异名.     

虾虎鱼类线粒体全基因组序列结构特征分析及系统发育关系探讨

虾虎鱼类体态变异大、体型小、种类多, 形态鉴定及谱系分类较为困难。为深入开展虾虎鱼类的鉴定、分类及遗传进化等研究, 文章对已获得的26种虾虎鱼线粒体全基因组进行分析。结果发现, 虾虎鱼类线粒体基因组的基因组成及排列模式与大多数脊椎动物线粒体基因组特征基本一致; 由于不同物种的控制区存在不同数量的重复序列而导致基因组序列长度存在明显的差异; 26种虾虎鱼线粒体全基因组序列及不同基因中A+T的含量均超过50%, 并存在碱基G偏倚现象。基于37个编码基因序列, 利用Kimura双参数法计算遗传距离, 发现矛尾刺虾虎鱼与斑尾刺虾虎鱼、斑纹舌虾虎鱼与钝吻舌虾虎鱼分别为同种异名。通过对26种虾虎鱼线粒体基因组控制区序列的比较, 识别了终止结合序列区、中央保守区及保守序列区。利用26种虾虎鱼线粒体基因组的36个编码基因序列构建系统发育树, 发现部分聚类结果不同于传统的形态学分类方式, 虾虎鱼科中的5个亚科出现了明显的分化, 近盲虾虎鱼亚科、背眼虾虎鱼亚科、瓢虾虎鱼亚科亲缘关系较近而聚成一大支, 然后与拟虾虎鱼亚科种类形成姐妹类群, 虾虎鱼亚科与其它的4个亚科亲缘关系较远, 单独成为一个类群。根据分子钟估算结果推测虾虎鱼科物种可能起源于始新世晚期至渐新世时段, 在中新世进一步分化为具有现代表征的虾虎鱼种类。     

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