草玉梅一新变种

发表草玉梅一新变种,大理草玉梅Ａｎｅｍｏｎｅ ｒｉｖｕｌａｒｉｓ Ｂｕｃｈ．＝ａｍ ｖａｒ ａｌｉｅｎｓｉｓ。     

单条草的皂甙成分

从单条草（ＬｙｓｉｍａｃｈｉａｃａｎｄｉｄａＬｉｎｄｌ）全草中分离出３个皂甙类化合物,经波谱分析并结合化学方法鉴定为：报春花素Ａ３ＯβＤ吡喃木糖基（１→２）βＤ吡喃葡萄糖基（１→４）［βＤ吡喃葡萄糖基（１→２）］αＬ吡喃阿拉伯糖甙（１）、原报春花素Ａ３ＯβＤ吡喃木糖基（１→２）βＤ吡喃葡萄糖基（１→４）［βＤ吡喃葡萄糖基（１→２）］αＬ吡喃阿拉伯糖甙（ｌｙｓｉｋｏｉａｎｏｓｉｄｅ,２）和α菠甾醇葡萄糖甙（３）。其中１是新化合物,命名为单条草甙（ｃａｎｄｉｄｏｓｉｄｅ）。     

鞭打绣球中的苯丙素甙和环烯醚萜甙

从鞭打绣球（ＨｅｍｉｐｈｒａｇｍａｈｅｔｅｒｏｐｈｙｌｌｕｍＷａｌｌ．）（玄参科）的全草中分离到２个新的苯丙素甙,命名为鞭打绣球甙Ａ和Ｂ（ｈｅｍｉｐｈｒｏｓｉｄｅＡａｎｄＢ）,２个已知的苯丙素甙,ｐｌａｎｔａｍａｊｏｓｉｄｅ和ｐｌａｎｔａｉｎｏｓｉｄｅＤ,以及３个已知的环烯醚萜甙,ｇｌｏｂｕｌａｒｉｃｉｓｉｎ,ｇｌｏｂｕｌａｒｉｎ和ｉｓｏ－ｓｃｒｏｐｈｕｌａｒｉｏｓｉｄｅ．通过化学和光谱分析,鞭打绣球甙Ａ和Ｂ的结构分别鉴定为２－（３－羟基－４－甲氧基苯基）乙基０－β－Ｄ－葡萄吡喃糖基（１→３）－４－Ｏ－反式阿魏醚基－β－Ｄ－葡萄吡喃糖试和２－（３,４－二羟基苯基）乙基Ｏ－［６－Ｏ－乙醚基－β－Ｄ－葡萄吡喃糖基（１→３）］－４－Ｏ－反式咖啡醚基－β－Ｄ－葡萄吡喃糖甙．     

中药玄参的化学成分

从中药玄参（ＳｃｒｏｐｈｕｌａｒｉａｎｉｎｇｐｏｅｎｓｉｓＨｅｍｓｌ．）中分离得到１个新化合物：４－Ｏ－（对甲氧基肉桂酰基）－α－Ｌ－鼠李糖［４－Ｏ－（ｐ－ｍｅｔｈｏｘｙｃｉｎｎａｍｏｙｌ）－α－Ｌ－ｒｈａｍｎｏｐｙｒａｎｏｓｅ］;同时还分离到４个已知的环烯醚萜甙：爪钧草甙（ｈａｒｐａｇｉｄｅ）,爪钩草酯甙（ｈａｒｐａｇｏｓｉｄｅ）,Ｏ－甲基梓醇（Ｏ－ｍｅｔｈｙｌｃａｔａｌｐｏｌ）,士可玄参甙Ａ（ｓｃｒｏｐｏｌｉｏｓｉｄｅＡ）和１个已知的苯丙素甙：安格洛甙Ｃ（ａｎｇｏｒｏｓｉｄｅＣ）。新化合物的结构通过化学降解和光谱分析得到证明。     

瓦草中三个新环肽

从云南民间中草药瓦草（Ｓｉｌｅｎｅｓｚｅｃｈｕｅｎｓｉｓ）的根中分离鉴定了３个新的环肽,分别命名为瓦草环肽Ａ,Ｂ,Ｃ（ｓｉｌｅｎｉｎｓＡ,Ｂ,Ｃ）用光谱和化学方法确定它们均为环八肽,其结构分别为：ｓｉｌｅｎｉａＡ－ｃｙｃｌｏ－（Ｐｒｏ－Ｌｅｕ－Ｓｅｒ－Ｐｈｅ－Ｐｒｏ－Ｔｙｒ－Ｌｅｕ－Ｖａｌ）,ｓｉｌｅｎｉｎＢ－－ｃｙｃｌｏ－（Ｐｈｅ－Ｌｅｕ－Ａｌａ－Ｐｒｏ－Ｌｅｕ－Ｐｒｏ－Ｐｈｅ－Ｐｒｏ）,ｓｉｌ     

红毛五加叶的三萜皂甙

红毛五加（ＡｃａｎｔｈｏｐａｎａｘｇｉｒａｌｄｉｉＨａｒｍｓ）系五加科五加属植物,分布于河北、河南、四川、陕西、甘肃等省,有祛风湿、通关节、强筋骨、治痿痹等功效［１］。其化学成分未见报道。本文报道红毛五加叶的５个三萜皂甙（甙Ⅰ、Ⅱ、Ⅲ、Ⅳ和Ⅴ）的分离鉴定。它们均首次从该属植物发现,其结构如下：　　　　　　　　　　　　　Ｒ１　　　　　　　　　　　　　　Ｒ２　　　　　　　　Ⅰ　ｒｈａｍ－（１→２）－ａｒａ　　　　　Ｈ　　　　　　　Ⅱ　Ｈ　　　ｒｈａｍ－（１→４）－ｇｌｃ－（１→６）－ｇｌｃ　　　　　…     

云木香化学成分研究Ⅱ

从丽江产云木香（ＳａｕｓｒｅａｌａｐｐａＣ．Ｂ．Ｃｌａｒｋｅ）根中分离得到的另外７个化合物,它们分别是＿孕甾烯醇酮（ｐｒｅｇｎｅｎｏｌｏｎｅ）（１）,β－谷甾醇（β－ｓｉｔｏｓｔｅｒｏｌ）（２）,葫萝卜甙（ｄａｕｃｏｓｔｅｒｏｌ）（３）,苯丙素甙（ｓｙｒｉｎｇｉｎ）（４）,木质素甙（１－ｈｙｄｒｏｘｙｐｉｎｏｒｅｓｉｎｏｌ－１－β－Ｄ－ｇｌｕｃｏｐｙｒａｎｏｓｉｄｅ）（５）,油酸［（ｚ,ｚ）－９,１２－ｏｃｔａｄｅｃａｄｉｅｎｏｉｃａｃｉｄ］（６）和油酸－１,３－甘油二酯［（ｚ,ｚ）－９,１２－ｏｃｔａｄｅｃａｄｉｅｎｏｉｃａｃｉｄ－２－ｈｙｄｒｏｘｙ－１,３－ｐｒｏｐａｎｅｄｉｎｙｌｅｓｔｅｒ］（７）．它们的结构通过波谱和化学的方法得到鉴定。其中化合物１作为天然产物首次从植物中分离得到,化合物３,４,５和７为首次从该植物中分离得到。     

蜘蛛抱蛋根茎中的甾体皂甙

从蜘蛛抱蛋（ＡｓｐｉｄｉｓｔｒａｅｌａｔｉｏｒＢｌ．）根茎的甲醇提取物中分离得两个甾体皂甙。经波谱解析及化学降解证明其化学结构分别为薯芋皂甙元一３一Ｏ－［Ｂ－Ｄ－葡萄吡喃糖基（１→２）］－［Ｂ－Ｄ－木吡喃糖基（１→３）］－Ｂ－Ｄ－葡萄吡喃糖基（１→４）－Ｂ－Ｄ一半乳吡喃糖甙（即蜘蛛抱蛋甙ａｓｐｉｄｉｓｔｒｉｎ）及新静诺特皂甙元－３－Ｏ－［Ｂ－Ｄ－葡萄吡喃糖基（１→２）］～［Ｂ－Ｄ－木吡喃糖基（１→３）－Ｂ－Ｄ－葡萄吡喃糖基（１→４）一Ｂ－Ｄ－半乳吡喃糖甙,后者为一新试,命名为新蜘蛛抱蛋甙ｒｅｏａｓｐｉｄｉｓｔｒｉｎ。     

大花地不容中的生物碱

大花地不容（ＳｔｅｐｈａｎｉａｍａｃｒａｎｔｈａＨ．Ｓ．ＬｏｅｔＭ．Ｙａｎｇ）系防己科千金藤属（Ｓｔｅｐｈａ－ｎｉａ）一新种［１］。其化学成分未见报道。今从其块根中分得８种生物碱,经鉴定,主要为ｌ－四氢巴马汀（ｌ－ｔｅｔｒａｈｙｄｒｏｐａｌｍａｔｉｎｅ,Ⅰ）和异紫堇定碱（ｉｓｏｃｏｒｙｄｉｎｅ,Ⅱ）,得率分别为０．８３％和１．８２％。其余为紫堇定碱（ｃｏｒｙｄｉｎｅ,Ⅲ）、紫堇单酚碱（ｃｏｒｙｄａｌｍｉｎｅ,Ⅳ）、千金藤定碱（ｓｔｅｐｈａｌｉｄｉｎｅ,Ⅴ）、巴马汀碱（ｐａｌｍａｔｉｎｅ,Ⅵ）、紫…     

藏玄参中的抑精三萜皂甙

从藏药植物藏玄参（ＯｒｅｏｓｏｌｅｎｗａｔｔｉｉＨｏｏｋ．ｆ．）的全草中分离到４个三萜皂甙,密蒙花甙（ｍｉｍｅｎｇｏｓｉｄｅ）Ａ和Ｂ及醉鱼草甙（ｂｕｄｄｌｅｊａｓａｐｏｎｉｎ）Ｉ和Ｉａ,另外还得到阿克甙（ａｃｔｅｏｓｉｄｅ）和６－羟基木犀草素－７－Ｏ－葡萄糖甙（６－ｈｙｄｒｏｘｙｌｕｔｅｏｌｉｎ－７－Ｏ－ｇｌｕｃｏｓｉｄｅ）。体外抑精实验表明,４个三萜皂甙均有较强的抑精活性,其中密蒙花甙Ａ和醉鱼草     

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.