仲彬草属5种植物的核型研究

本文对我国西部高原仲彬草属Ｋｅｎｇｙｉｌｉａ５种植物的核型进行了分析。它们的染色体数目均为２ｎ＝４２,六倍体。核型是：糙毛鹅观草Ｋ．ｈｉｒｓｕｔａ,２ｎ＝６ｘ＝４２＝３６６＋６ｓｍ;青海鹅观草Ｋ．ｋｏｋｏｎｏｒｉｃａ,２ｎ＝６ｘ＝４２＝３６ｍ＋６ｓｍ：黑药鹅观草Ｋ．ｍｅｌａｎｔｈｅｒａ,２ｎ＝６ｘ＝４２＝３８ｍ＋４ｓｍ;硬秆鹅观草Ｋ．ｒｉｇｉｄｕｌａ,２ｎ＝６ｘ＝４２＝３８ｍ＋４ｓｍ;窄颖鹅观草Ｋ．ｓｔｅｎａｃｈｙｒａ,２ｎ＝６ｘ＝４２＝３８ｍ＋４ｓｍ。它们的核型属于１Ｂ或２Ｂ型。染色体中均未发现随体。     

鹅观草与大鹅观草杂种的细胞遗传学及形态学研究

大鹅观草（ Ｒｏｅｇｎｅｒｉａ ｇｒａｎｄｉｓ Ｋｅｎｇ） 是分布于我国陕西的一种多年生四倍体植物。为了探索大鹅观草与鹅观草（ Ｒｏｅｇｎｅｒｉａ ｋａｍｏｊｉ Ｏｈｗｉ） 间的物种生物学关系, 通过对其进行远缘杂交,幼胚离体培养, 合成了远缘杂种; 并对亲本及杂种Ｆ１ 代花粉母细胞减数分裂中期Ⅰ染色体配对行为及形态学进行了研究。结果表明杂种Ｆ１ 减数分裂染色体配对平均构型为： Ｒ－ ｋａｍｏｊｉ ×Ｒ－ｇｒａｎｄｉｓ１０－２６ Ⅰ＋ １２－３７ Ⅱ（ｃ－ 值＝ ０－７４） , 大鹅观草与鹅观草所含的ＳＹ 染色体组间存在较大的同源性分化; 杂种穗部特征大多数介于双亲之间。     

中国禾草三新种

报道了禾本科鹅观草属二新种和以礼草属一新种,即稀节鹅观草（Ｒｏｅｇｎｅｒｉａｌａｘｉｎｏｄｉｓ）,缩芒鹅观草（Ｒｏｅｇｎｅｒｉａｃｕｒｔｉａｒｉｓｔａｔａ）和沙湾以礼草（Ｋｅｎｇｙｉｌｉａｓｈａｗａｎｅｎｓｉｓ）．     

赖草的种间和属间杂种胚胎培养研究

以小麦族赖草属植物的６个种：赖草（Ｌｅｙｍｕｓｓｅｃａｌｉｎｕｓ）、窄颖赖草（Ｌ．ａｎｇｕｓｔｕｓ）、单小穗赖草（Ｌ．ａｅｍｕｌａｎｓ）、多枝赖草（Ｌ．ｍｕｌｔｉｃａｕｌｉｓ）、大赖草（Ｌ．ｒａｃｅｍｏｓｕｓ）和天山赖草（Ｌ．ｔｉａｎｓｈａｎｉｃｕｓ）作试验材料,分别组配成５个种间杂交组合,并与新麦草属（Ｐｓａｔｈｙｒｏｓｔａｃｈｙｓ）、鹅观草属（Ｒｏｅｇｎｅｒｉａ）以及Ｔｈｉｎｏｐｙｒｕｍ属组配成９个属间杂交组合。应用胚胎培养技术,离体培养杂种胚胎,成功地拯救了赖草植物的种间和属间杂种。试验结果表明,杂种胚胎的胚龄、培养基的营养组成以及杂种基因型对离体胚胎的培养有明显影响。     

竹节花黄斑驳病毒启动了在棉花维管组织中是一个强启动子

用竹节花黄斑驳病毒（Ｃｏｍｍｅｌｉｎａ Ｙｅｌｌｏｗ Ｍｏｔｔｌｅ Ｖｉｒｕｓ,ＣｏＹＭＶ）启动子－ｇｕｓ嵌合基因和ＣａＭＶ３５Ｓ－ｇｕｓ嵌合基因通过根癌土壤杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍｅｆａｃｉｅｎｓ（Ｓｍｉｔｈ ｅｔ Ｔｏｗｎｓｅｎｄ）Ｃｏｎｎ）ＬＢＡ４４０４介导分别转入棉花（Ｇｏｓｓｙｐｉｕｍ ｈｉｒｓｕｔｕｍ Ｌ．ｃｖ．Ｊｉｎｇｍｉａｎ７,Ｊ７Ｇ）,诱导再生了棉花转基因植株。Ｇ     

腔孢纲真菌的三个新种

在调查香龙血树Ｄｒａｃａｅｎａ ｆｒａｇｒａｎｓ（Ｌ．）Ｋｅｒ－Ｇａｎｌ．的病害中,发现了腔孢纲真菌的３个新种,即：Ｐｈｌｍｏｐｓｉｓ ｄｒａｃａｅｎｉｃｏｌａＺ．Ｄ．Ｊｉａｎｇ,Ｐ．Ｇ．Ｘｉ ｅｔ Ｐ．Ｋ．Ｃｈｉ,Ｂａｒｔａｌｉｎｉａ ｄｒａｃａｅｎａｅ Ｐ．Ｇ．Ｘｉ,Ｚ．Ｄ．Ｊｉａｎｇ ｅｔ Ｐ．Ｋ．Ｃｈｉ及Ｓｐｈａｅｒｏｐｓｉｓ ｄｒａｃａｅｎａｅ Ｐ．Ｇ．Ｘｉ ｅｔ Ｐ．Ｋ．Ｃｈｉ,模式标     

华山新麦草和鹅观草属两个种间物种生物学研究

通过华山新麦草（２ｎ＝１４,ＮＮ）和鹅观草属的两个种（纤毛鹅观草（２ｎ＝２８ ＳＹ）和鹅观草（２ｎ＝４２ ＳＨＹ）属间杂交,两个组合均得到生长健壮的植株。杂种Ｆ１形态上均为双亲的中间型。纤毛鹅观草Ｘ华山新麦草和鹅观草Ｘ华山新麦草杂种Ｆ１染色体配对构型分别为：２０．７３Ｉ＋０．３１８Ⅱ,２４．８０１Ⅰ＋１．５７Ⅱ＋０．０１２Ⅲ。后期Ⅰ均出现多极分离。两个组合均发现减数分裂过程异常现象。两个组合染色体     

国产前原鹅观草的订正

对我国文献中记载的前原鹅观草（Ｒｏｅｇｎｅｒｉａｍａｙｅｂａｒａｎａ（Ｈｏｎｄａ）Ｏｈｗｉ）的标本和植物,与原产于日本的该种进行了比较形态学、细胞学研究,二者差异显著。作者认为我国所记载的该种种名应是山东鹅观草（Ｒｏｅｇｎｅｒｉａｓｈａｎｄｏｎｇｅｎｓｉｓ（Ｂ．Ｓａｌｏｍｏｎ）Ｊ．Ｌ．Ｙａｎｇ,Ｙ．Ｈ．ＺｈｏｕｅｔＹｅｎ）,其内稃先端钝圆,长为外稃的３／４,染色体数为２ｎ＝４ｘ＝２８,具ＳＹ染色体组,结实率达９０％以上,过去被错定为Ｒ．ｍａｙｅｂａｒａｎａ。而Ｒ．ｍａｙｅｂａｒａｎａ在日本系一天然杂种,其内稃先端尖,与外稃等长或稍短,染色体数为２ｎ＝６ｘ＝４２,具ＨＳＹ染色体组,结实率极低,仅０．２％～０．４％。     

ELYMUS SIBIRICUS,E.NUTANS和E.BURCHAN—BUDDAE的形态学鉴定及其染色体组

为了进一步研究Ｅｌｙｍｉｕｓ ｓｉｂｉｒｉｃｕｓ Ｌ．,Ｅ．ｎｕｔａｎｓ Ｇｒｉｓｅｂ．和Ｅ．ｂｕｒｃｈａｎ－ｂｕｄｄａｅ（Ｎｅｕｓｋｉ）Ｔｚｅｌｅｖ［＝Ｒｏｇｅｇｎｅｒｉａ ｎｕｔａｎｓ （ｋａｎｇ） Ｋｅｎｇ］ 的外部形态差及其系统学关系,本文对这三种植物的６个穗部形态性态状进行了观测和比较,并对这三个Ｅｌｙｍｕｓ种进行了种间杂交及杂种Ｆ１的减数分裂染色体配对行为的分析研究。结果表明：这三个Ｅ     

中国云南发现珍稀濒危树蕨巨大古树——屏边桫椤

屏边桫椤新种当地名：多头树蕨、树蕨王图１：１～８图版１：１～４ＡｌｓｏｐｈｉｌａｐｉｎｇｂｉａｎｉｃａＹ．Ｋ．Ｙａｎｇ．Ｙ．Ｍ．ＨｅｅｔＪ．Ｋ．Ｗｕｓｐ．ｎｏｖ．ＳｐｅｃｉｅｓｎｏｖａａｆｉｎｉｓＡｌｓｏｐｈｉｌａｃｏｓｔｕｌａｒｉｓＢａｋ．ｅｔＡｌ...     

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.