中国蚊蝎蛉属四新种记述(长翅目,蚊蝎蛉科)

记述了中国蚊蝎蛉属Bittacus Latreille 4新种,即暗蚊蝎蛉Bittacus obscurus sp.nov.,浅黄蚊蝎蛉Bittacusflavidus sp nov,长突蚊蝎蛉Bittacus longiprocessus sp.nov.和四边蚊蝎蛉Bittacus trapezoideus sp.nov..模式标本保存于西北农林科技大学昆虫博物馆.     

米仓山蚊蝎蛉二新种记述(长翅目:蚊蝎蛉科)

记述陕西南部米仓山蚊蝎蛉2新种,净翅蚊蝎蛉Bittacus puripennatus Cai et Hua和缠绕蚊蝎蛉Bittacus implicatus Huang et Hua。模式标本均保存在西北农林科技大学昆虫博物馆。     

浙江蚊蝎蛉属一新种(长翅目,蚊蝎蛉科)

记述了产于中国浙江的蚊蝎蛉属Bittacus Latreille,1805 1新种,浙江蚊蝎蛉Bittacus zhejiangicus sp.nov.,提供了雄性正模成虫的整体照片,绘制了雄性和雌性外生殖器特征图。新种与中华蚊蝎蛉Bittacus sinensis Walker和天目山蚊蝎蛉B.tienmushana Cheng相似,但根据羽状触角,翅Av脉存在,前足腿节明显黑褐色,雄性上生殖瓣基部下缘大的耳状突起,载肛突末端有1小突起,突起上有1束长毛,生殖肢端节不具突起等特征容易区分。正模♂,采于浙江凤阳山七星潭;副模: 1♀,采于浙江泰顺乌岩岭; 1 ♂,采于浙江庆元百山祖。模式标本分存于西北农林科技大学昆虫博物馆[NWAU]和上海昆虫博物馆[SHEM]。     

扁蚊蝎蛉的行为学观察

通过室内饲养和观察,记述了扁蚊蝎蛉Bittacus planusCheng成虫捕食过程、雌雄交配和产卵行为。捕食过程分准备、捕捉、取食和清洁等4个步骤。观察到了雄虫的献礼行为,雌虫边取食边交配。存在有自相残杀行为。     

蚊蝎蛉捕捉足构造

依据光学显微镜和扫描电镜观察,对扁蚊蝎蛉Bittacus planus Cheng和缠绕蚊蝎蛉Bittacus implicatus Huang et Hua成虫足的外部形态、肌肉组织及超微结构进行了描述和绘图。蚊蝎蛉成虫三对足结构相似,均为捕捉式,以高度特化的跗节捕捉猎物,各跗分节间具发达的关节、凹槽和爪缩肌肌腱膨大区,第4和5跗分节的齿形成嵌合构造,在昆虫纲中为该类群独有特征。首次发现胫节伸肌b由腿节基部发出的一小块三角形肌肉组织和一条长肌腱组成; 爪缩肌肌腱在第5跗分节凹槽末端有一突起,收缩时突起羁绊于凹槽内的“Y”字形底托。分析了成虫捕食行为与捕捉足构造之间的关系,并简要比较了蚊蝎蛉捕捉足与螳螂捕捉足的结构特点。     

蝎蛉科与蚊蝎蛉科昆虫触角感器超微形态比较

触角是昆虫重要的感觉器官,其感觉功能主要是通过其上的各类感器来实现的。本文以染翅蝎蛉Sinopanorpa tincta(Nav偄s)和中华蚊蝎蛉Bittacus sinensis Walker为代表,采用扫描电子显微镜观察了蝎蛉科Panorpidae和蚊蝎蛉科Bittacidae触角感器的类型及其超微结构,并简要讨论了各种感器的功能。结果显示:染翅蝎蛉触角上共发现7种感器,分别为短刺形感器、Bhm氏鬃毛、毛形感器、短毛形感器、锥形感器、刺形感器、和微毛形感器。中华蚊蝎蛉触角上也发现7种感器,分别为Bhm氏鬃毛、芽形感器、毛形感器、刺形感器、畸形毛感器、腔锥感器和钟形感器。蚊蝎蛉触角与蝎蛉的最大区别是着生有大量的腔锥感器,初步推测众多的腔锥感器可能与蚊蝎蛉对湿度的高度敏感有关。     

淡黄蚊蝎蛉染色体特征及其系统发育意义

【目的】染色体特征在昆虫系统发育研究中起着重要作用。然而,长翅目(Mecoptera)蚊蝎蛉科(Bittacidae)昆虫的染色体研究却比较匮乏。【方法】通过室内饲养获得淡黄蚊蝎Bittacus flavidus Huang & Hua各龄幼虫、蛹和成虫。取淡黄蚊蝎雄性末龄(4龄)幼虫、蛹和新羽化成虫精巢细胞进行染色体制片,通过4′,6-二脒基-2-苯基吲哚(4′,6-diamidino-2-phenylindole, DAPI)荧光染色,研究染色体核型、减数分裂行为和性别决定机制。【结果】结果表明,淡黄蚊蝎蛉的染色体数目为2n=26+X0,染色体均具有中着丝粒,核型高度对称。二价体绝对长度为(3.20±0.07)~(1.53±0.19) μm,相对长度为(5.31±0.29)~(2.73±0.24),均呈梯度变化。淡黄蚊蝎蛉的减数分裂为交叉型,其中核的平均交叉频率为11.5,二价体的平均交叉频率为0.88。性别决定机制为XX/X0型。DAPI荧光带型显示,粗线期二价体一端呈现高亮的AT富集区块。【结论】染色体特征(包括染色体数目、染色体臂基本数和核型公式等)在蚊蝎蛉科中表现出显著变异,表明染色体重排(尤其是融合、断裂和倒位)在蚊蝎蛉科昆虫的谱系分化和染色体演化中起着重要作用。     

中国东北晚侏罗世蝎蛉化石研究(长翅目:蚊蝎蛉科,直脉蝎蛉科)(英文)

本文描述蝎龄化石1新属4新种。新属Megabittacus2新种,即Megabittacuscolosseussp.nov.,Megabittacusbeipiaoensissp．nov,新种Sibirobittacusatalussp.nov.属于现生的蚊蝎蛉科,新种Orthophlebialiaoningensissp．nov．属于绝灭的直脉蝎蛉科。化石采于辽宁省北票市晚侏罗世义县组地层中。这些新的化石属种,其虫体特征包括触角、喙、足和翅脉特征均完整的保存。模式标本保存在中国地质博物馆。     

长蝎蛉幼期形态附生物学记述

【目的】蝎蛉科(Panorpidae)是长翅目(Mecoptera)最大的科,是重要的生态指示昆虫。然而,由于对环境条件要求苛刻,饲养困难,其幼期研究很不充分。【方法】本研究通过人工饲养成虫获得了长蝎蛉Panorpa macrostyla Hua的卵、幼虫和蛹等全部虫态,运用光学显微镜和扫描电子显微技术观察了其超微形态,并简要记载了其生物学特性。【结果】长蝎蛉每年发生1代,成虫发生于6月末至8月初。卵椭球形,卵壳表面覆盖一层隆起的网状结构。幼虫蠋型,具3对分4节的胸足和8对不分节的腹足;头壳高度骨化,具1对由26个小眼组成的复眼和1对3节的触角,口器咀嚼式;腹部第1-9节背面具有成对的背毛突,第10节仅有1根背毛突,腹部末端具有一个可伸缩的吸盘;呼吸系统为周气门式,具1对前胸气门和8对腹气门。幼虫共4个龄期,以预蛹期在土室内越冬。蛹为强颚离蛹,外形接近成虫,雄蛹腹部末端膨大。【结论】基于幼虫形态特征,长蝎蛉明显区别于新蝎蛉属Neopanorpa、华蝎蛉属Sinopanorpa、双角蝎蛉属Dicerapanorpa以及单角蝎蛉属Cerapanorpa幼虫。然而,长蝎蛉幼虫头部刚毛L2和SO2,腹部末节刚毛D2,SD1和SD2端部均膨大呈棒状,与蝎蛉属Panorpa其他种类区别明显,表明长蝎蛉的属级地位需要进一步研究。     

陕西秦岭蝎蛉的生物学观察

2004～2005年,在陕西省南部米仓山黎坪国家森林公园研究了秦岭蝎蛉Panorpa qinlingensis Chou et Ran的年生活史和生物学习性,通过饲养,成功获得卵、幼虫、蛹等虫态。结果表明,秦岭蝎蛉在米仓山1年发生2代,以预蛹在土室里越冬,5月中旬始见越冬代成虫,5月中旬末～6月上句为越冬代成虫羽化盛期,7月下旬～8月中句为第1代成虫羽化盛期,成虫在室内可存活35～60d。羽化近1周后开始交尾,交尾4～8d后开始产卵,单雌产卵量35～180粒,卵期5～9d;幼虫蝴型,共4龄。历期38～50d;蛹为强颚离蛹,蛹期8—18d。记述了主要生物学习性。     

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.     

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.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.