重庆发现云南小狭口蛙及其系统发育关系

2021年5月在重庆武隆仙女山国家森林公园采集到3号小狭口蛙标本,经形态学及分子生物学鉴定为云南小狭口蛙（Glyphoglossus yunnanensis）,属重庆市两栖动物分布新记录种。本文给出了这3号标本的17项外形特征测量值,并描述了其生境特征。对10个不同地理种群的云南小狭口蛙种群相关16S rRNA基因片段构建最大似然树表明,重庆武隆标本与云南小狭口蛙产地标本序列聚在一起,且其间的遗传距离为0.6%,远远小于小狭口蛙属物种之间的遗传距离。重庆武隆的这一分布点,使得对云南小狭口蛙在我国分布的认知往东北延伸了超过350 km。云南小狭口蛙在重庆武隆的分布新记录能帮助理解该物种潜在分布区以及谱系地理。     

陕西省发现绿臭蛙

在陕西省宁强县青木川国家级自然保护区采集了6只臭蛙类标本,经形态特征比较,鉴定为绿臭蛙(Odorrana margaretae),为陕西省首次发现。本文对其特征和分布进行了讨论。     

贵州威宁发现景东臭蛙

2020年8月6日在贵州省威宁县雪山镇（27°04′09″N,104°04′44″E,海拔2 218 m）采集到6号两栖动物标本,经形态特征比较,与景东臭蛙（Odorrana jingdongensis）相似;基于线粒体16S rRNA构建臭蛙属（Odorrana）部分物种系统发育树,此次采集的臭蛙标本与景东臭蛙聚为一支,且具有较高的支持率（0.97/92,贝叶斯法/最大似然法）;基于Kimura双参数模型估算本次采集的臭蛙标本与景东模式产地标本间的遗传距离为0%,远小于臭蛙属物种间的遗传距离（1.3%～9.5%）。综合形态特征和分子系统发育比较,确定此次采集到的臭蛙标本为无尾目（Anura）蛙科（Ranidae）臭蛙属的景东臭蛙,系贵州省两栖动物分布新记录种。     

云南高黎贡山发现僜湍蛙和察隅湍蛙

2021年4和5月及7和8月在云南省高黎贡山开展两栖爬行动物调查过程中,采集到无尾目（Anura）蛙科（Ranidae）湍蛙属（Amolops）标本8号,通过形态学与分子系统学鉴定为僜湍蛙（Amolops deng）和察隅湍蛙（A. chayuensis）,为云南省两栖动物分布新纪录种。僜湍蛙雌性体长63.1 ~ 68.5 mm（n = 3）,雄性体长49.3 ~ 52.9 mm（n = 3）,头长大于头宽,鼓膜明显且纵径大于横径,掌突三个,颞褶不显,背侧褶直达胯部,后肢前伸贴体时胫跗关节超过吻端,形态特征与模式标本基本一致;察隅湍蛙雄性体长44.7 ~ 44.8 mm（n = 2）,具咽侧下外声囊,颞褶及背侧褶明显,前后肢均具褐色条纹,形态特征与模式标本基本一致。基于线粒体16S rRNA基因和COI基因片段进行系统发育分析表明,僜湍蛙和察隅湍蛙均和其模式产地西藏的序列聚成单系支。此外,基于16S rRNA计算本次采集的标本与模式产地西藏的序列间遗传距离均较小,僜湍蛙是0.8% ~ 1.2%,察隅湍蛙是0.2%。综上,确定云南高黎贡山采集到的两种湍蛙分别是僜湍蛙和察隅湍蛙。僜湍蛙此前记录仅分布于西藏察隅县和墨脱县,察隅湍蛙仅分布于西藏察隅县和八宿县,僜湍蛙在福贡县和贡山县及察隅湍蛙在贡山县的分布为首次记录;本研究进一步更新了察隅湍蛙分布的海拔海拔范围,较此前纪录低1 385 m高至2 884 m,这提示其有更广阔的生态位。     

安徽黄山发现孟闻琴蛙

琴蛙属(Nidirana)是广泛分布于东洋界的两栖动物，目前安徽省琴蛙属仅记录了弹琴蛙 (N. adenopleura)1种。2022年7月在安徽省黄山地区(九龙峰自然保护区和马金岭自然保护区)采集到9号两栖动物标本，其形态特征与孟闻琴蛙(N. mangveni)相似；此外，基于线粒体COI基因片段的分子系统发育分析显示，此次采集到的琴蛙标本与孟闻琴蛙聚为一支，且具有高的支持率(贝叶斯后验概率/最大似然支持率为1.00/98%)，而且和孟闻琴蛙遗传距离最近，与模式产地的孟闻琴蛙遗传距离仅有0.04%。因此，结合形态比较和分子系统学分析，鉴定此次采集的琴蛙属标本为孟闻琴蛙，为安徽省两栖动物分布新记录种。这一发现将孟闻琴蛙的分布范围扩展至皖南地区，为琴蛙属和皖南地区的生物地理学和地史研究提供了重要数据。     

中国蛙科一新种(两栖纲,无尾目)

对分布于广西龙胜和湖南宜章的龙胜臭蛙Odorrana(Odorrana)lungshengensis作了进一步比较研究,发现两者的形态特征有明显区别,并将湖南宜章的标本命名为新种--宜章臭蛙Odorrana(Odorrana)yizhangensis sp.nov..     

陕西镇坪发现光雾臭蛙

2022年6月在陕西省安康市镇坪县化龙山自然保护区(32°00′01″ N,109°17′05″ E,海拔1 641 m)采集到1号无尾两栖类标本,经形态特征比较确认为臭蛙属(Odorrana)物种,基于线粒体16S rRNA分子片段对臭蛙属35个物种的系统发育进行分析,其与模式产地四川南江的光雾臭蛙(O. kuangwuensis)在最大似然系统发育树中聚为一支,支持率高达99%,且遗传分化较小,应属种内关系。综合形态特征比较和系统发育分析,确定采集到的标本为无尾目(Anura)蛙科(Ranidae)臭蛙属的光雾臭蛙,系陕西省两栖动物分布新记录种,此发现为光雾臭蛙在大巴山脉分布的连续性提供了一定依据。     

贵州省两栖动物新纪录——宜章臭蛙及其系统发育分析

2015年5月至7月在贵州省梵净山国家级自然保护区采集到6号臭蛙标本,经鉴定为宜章臭蛙(Odorrana yizhangensis)(两栖纲,无尾目,蛙科),属贵州省两栖动物新纪录。本文给出了这6号标本的22项外形特征量度,并描述了其生境特征。基于12S r RNA和16S r RNA基因片段构建的最大似然系统发育树表明,这些标本与宜章臭蛙模式产地标本聚在一起,且他们之间的遗传距离远远小于臭蛙属物种之间的距离。宜章臭蛙在贵州的新记录将促进该物种的分类与谱系地理学研究。     

重庆市发现宜章臭蛙

2014年7~8月在重庆市南川区三泉镇采集到5号臭蛙类标本,经形态特征比较和DNA数据比对及遗传距离分析,鉴定为宜章臭蛙(Odorrana yizhangensis),属重庆市新纪录。重庆南川的宜章臭蛙与模式产地标本相比,指关节下瘤雌蛙较雄蛙明显;有外掌突;趾关节下瘤明显,趾间全蹼;后肢前伸贴体时胫跗关节超过吻端。重庆南川区与湖南宜章经度和纬度相距均约5°,为宜章臭蛙已知分布的最西点。宜章臭蛙的形态和遗传分化及分布格局,是否由于我国滇西高山峡谷地区、粤桂湘赣南岭山地和湘渝鄂边境地区特殊地理效应及第四纪冰期气候的反复变化造成的,值得进一步探讨。     

云南省发现弄岗狭口蛙

2018年6月,在位于云南省文山壮族苗族自治州的文山国家级自然保护区(23°21′41″N,104°50′26″E,海拔1 300 m)采集到无尾目(Anura)姬蛙科(Microhylidae)狭口蛙属(Kaloula)标本3号,包括雄性成体标本1号和雌性成体标本2号,并对相应形态特征进行了测量,雄性头体长为35.79mm,雌性头体长为48.01 mm和42.78 mm。根据形态特征比较发现,该种群的标本皮肤光滑,背部呈橄榄绿色,有不规则的深绿色斑纹,指端平切且具两排小乳突,雄性胸部有小柠檬黄色斑点,雄性全蹼,雌性为1/3蹼,与采集自弄岗国家级自然保护区的弄岗狭口蛙(K. nonggangensis)地模标本(海拔186 m)的形态鉴定特征基本一致,仅体色和体型大小稍有差异。基于16S rRNA基因片段进行系统发育分析表明,这些标本与弄岗狭口蛙模式产地标本聚在一起,共享同一单倍型。可以确定所采集的3号标本均为弄岗狭口蛙,为云南省两栖纲分布新记录物种。新发现的种群分布于中高海拔处,较地模标本的低海拔分布记录有较大的拓展。该物种的发现说明,云南东南部与广西西南部的喀斯特地区具有相似的物种组成,对该区域将来的生物地理学研究具有重要意义。     

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.