五节芒基因组大小测定

五节芒(Miscanthus floridulus)属于禾本科(Poaceae)芒属(Miscanthus Andersson),被认为是一种开发潜力巨大的生物质能源植物。本研究以水稻日本晴(Oryza sativa L.var.Nipponbare)为内标,采用流式细胞仪测定6份采自中国不同地区的五节芒基因组大小。结果首次确定了五节芒的基因组大小平均为2596.59 Mb,即2 C DNA含量为5.31 pg(以1 pg=978 Mb计算)。     

小麦EST-SSR标记对几种有潜力的禾本科能源植物的可转移性研究

为了筛选出一些有用可靠的分子标记,应用于禾本科能源植物的遗传化研究及种质资源评价,检测了48对源于小麦(Triticum aestivum)EST序列的SSR引物对7种有潜力的禾本科能源植物:斑茅(Saccharumarundinaceum)、中国芒( Miscanthus sinensis)、五节芒( M.floridulus)、河八王(Narenga porphyrocoma、南荻(Triarrhena lutarioriparia)、营(Themeda villosa和香根草(Vetiveria zizanioides)的可转移性.结果表明,在48对小麦EST-SSR引物中,36对具可转移性,可转移率为75.0％.这些可转移引物在7个物种中共检测出240个位点,其中多态性位点为184个,多态位点百分率高达76.7％.每个位点的PIC变幅为0～0.370,平均为0.220.利用EST-SSR数据构建了所研究的7种禾本科植物的系统发育树,其中斑茅、河八王、南荻及营被聚为A组,中国芒和五节芒聚为B组,香根草单独聚为C组,基本与形态学分类一致.因此,小麦EST-SSR分子标记在禾本科近源物种中的可转移性较高,对禾本科能源植物的遗传育种研究具有重要的参考价值.     

广东楝科植物分类的初步研究

本文是对广东楝科植物种类的初步整理、研究,记载了16属33种7交种,包括本省产的13属27种7变种和外来引种的3属6种。其中有1个新变种(封开地黄连Munronia hainanensis How et T. Chen var. microphyllina X. M. Chen),3个新组合(曾椤Amoora tsangii (Merr.) X. M. Chen, 雷楝Reinwardtiodendron dubium (Merr.) X. M. Chen, 毛香椿Toona sinensis (A. Juss.) M. J. Roem. var. schensiana (C. DC.) X. M. Chen), 3个分布新记录[雷楝属Reinwardtiodendron (我国新记录),鹧鸪花Trichilia connaroides (W. et A.) Bentv. var. connaroides(广东新记录),海南(木坚)木Dysoxylvm hainanense Merr. var. hainanense(广东大陆新记录)].     

玉米SSR引物在芒属植物遗传多样性分析的应用研究

目的:本文为了探索芒属植物的遗传多样性,方法:运用SSR分子标记的方法,用30对玉米SSR引物对15份中国湖南省的野生芒属材料进行扩增.结果:结果表明:30对引物共扩增出159条带,其中多态性条带121个,占76.10%.平均Nei's基因多样度为0.1992,平均Shannon信息指数为0.3139.UPGMA聚类分析显示,15份材料在遗传相似系数(GS)为0.75水平上,聚成三大类.第一大类由芒组成,第二大类由五节芒组成,第三大类由南获组成.这与形态学上的分类吻合.结论:玉米的SSR引物对于芒属植物遗传多样性分析仍具有很好的可行性.     

能源作物芒属双药芒组SSR引物的筛选及其评价

禾本科芒属植物具有在边际性土地(marginal land)上驯化成为高产能源作物的巨大潜力,其中尼泊尔芒(Miscanthus nepalensis)和双药芒(M.nudipes)两个双药芒组物种分布于喜马拉雅-黄断山地区,是具有耐寒及抗旱特性的优良种质资源.为了了解其遗传多样性和群体遗传结构,需要筛选出有效的分子标...     

芒属植物资源研究、利用现状和开发前景北大核心CSCD

对芒属17种植物的自然资源状况,从分类学、遗传育种学和生理学等方面研究的进行了综述,梳理了芒属植物资源利用现状,并展望了芒属植物的应用前景和产业价值。同时指出,对芒属类群的研究深度和应用程度极不均衡,对适应于极端环境的地区特有类群开发利用不够。为全面促进芒属植物资源开发利用,助力芒属新品种的研发和推广,倡议加强极端环境下芒属种质资源研发,实现更广阔的应用前景。     

中国某些野生和栽培茶的核型研究

研究了茶的4个变种和广东野生毛叶茶等共12个材料的核型。所有材料的染色体数目均是2n=30,为二倍体。所有中国大叶变种(越南大叶除外)(Cametlia sinensis var. macrophylla)和阿萨姆大叶变种(C. sinensis var. assamica)均具比较对称或原始的“2A”核型;中国小叶变种(C.sinensis var.bohea)(“铁观音”品种除外),掸部变种(C.sinensis var. shan form)和广东野生毛叶茶(C. ptilophylla)均具较不对称或较进化的“2B”核型。根据核型特征,植物习性和地理分布,作者认为中国四川和云南可能是茶的起源中心,向东或北迁移,演变为中国小叶变种;向南移则演变为阿萨姆变种和掸部变种。     

芒和五节芒在中国的潜在分布

利用最大熵模型, 将我国现有芒(Miscanthus sinensis)和五节芒(M. floridulus)的地理分布信息与19个降水及温度等气候因子相拟合, 预测了芒和五节芒在我国的潜在分布区域, 并推测出芒和五节芒的基本生态位。结果显示: 芒的潜在适生区包括四川西部、陕西北部、宁夏、内蒙古中部、黑龙江、吉林西部、辽宁西部、青海东南部等地区, 其基本生态位参数为: 最暖季节降水量为400-1 000 mm, 平均8月降水量为100-350 mm, 7月平均最低气温为15 ℃, 平均7月降水量为100-350 mm, 11月平均最高气温为-10-22 ℃, 最干月平均气温为-15-20 ℃, 平均12月降水量为100 mm以下; 五节芒的潜在适生区为云南、陕西、山西、宁夏、河南、山东、吉林、辽宁以及四川西部、甘肃南部和内蒙古东部等地区, 其基本生态位参数为: 最暖季节降水量至少在400 mm以上, 平均6月降水量为150-550 mm, 7月平均最低气温在15-30 ℃之间, 6月平均最低气温为10 ℃, 平均4月降水量为50-100 mm。结果表明, 在进行遗传改良的前提下, 我国有丰富的适合栽植芒和五节芒的土地资源。     

湖北省植物分布新记录(一)

该文报道了湖北省植物分布的新记录种7个,新记录变种2个,隶属于7科8属,分别为大叶茜草(Rubia schumanniana)、光枝杜鹃(Rhododendron haofui)、黄花葱(Allium condensatum)、小叶绣球藤(Clematis montana var.sterilis)、台湾人字果(Dichocarpum arisanense)、杨梅蚊母树(Distylium myricoides)、西康绣线梅(Neillia thibetica)、尾叶中华绣线梅(Neillia sinensis var.caudata)、粗毛牛膝菊(Galinsogaquadriradiata),并提供了地理位置、海拔及植物照片。引证标本均存于中南民族大学植物标本馆。     

长兴石灰岩中的(虫筳)科化石*

一.前言本文所研究的(虫筳)科化石,共计6属5种2变种及三个不能定种名的标本。其中(1)Palaeofusulina wangi Sheng(sp.nov.),P.wangi var.chumipuensis Sheng(var.nov.)采自贵州桐梓楚米铺附近长兴石灰岩中(Sh 136);(2)Palaeofusulinawangi Sheng(sp.nov.),P.sinensis Sheng(sp.nov.),P.sinensis var.fusiformis     

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.