瘿花香茶菜的微量成分

从唇形科瘿花茶菜（Ｒａｂｄｏｓｉａ ｒｏｓｔｈｏｒｎｉｉ）叶的乙醚抽出物中分出２个新的微量成分,瘿花丙素和丁素。基于详细的光谱分析,包括应用二维核磁共振数据,瘿花丙素和化学结合分别确定为对映－１１α－乙酰氧基－７β,１３β,１９－三羟基贝壳杉－１６烯－１５－酮（１）和对映－１１α－乙酰氧基－７β,１２β,１４α－三羟基贝壳杉－１６烯－１５－酮（２）。     

西北蔷薇果实化学成分的研究

从西北蔷薇（Rosa davidii Crep.)果实中分得１１个化合物,经波谱方法鉴定为：２α,３β,１９β－三羟基－齐墩果烷－１２－烯－２８－酸（１）２α,３β－二羟基－乌苏烷－２８（１３）－内酯（２）、arjunic acid(3)、蔷薇酸（４）、２α,３β－二羟基乌苏酸（５）、齐墩果酸（６）、山奈素（６）、tiliroside(８）、槲皮素（９）、胡萝卜甙（１０）和β－谷甾醇（１１）。其中１和２为首次发现的新化合物。     

光轴苎叶Ju的化学成分研究

从光轴苎叶Ｊｕ地上部分甲醇浸膏中分得１１个化合物,经波谱分析确定其结构分别为：β－谷旮醇（４）,４－烯－６β－羟基－３豆甾烷酮（２）,麦角甾醇过氧化物（３）,α－软脂酸甘油酯（４）,（Ｅ）－３,４－亚甲二氧基苯丙烯醛（５）,胡椒碱（６）,胡椒次碱（７）,荜拔明宁碱（８）,ｇｕｉｎｅｅｎｓｉｎｅ（９）,ｃｅｐｈａｒａｎｏｎｅＡ（１０）,ｃｅｐｈａｒａｎｏｎｅＢ（１）。     

藤山柳的化学成分

从藤山柳〖Ｃｌｅｍａｔｏｃｌｅｔｈｒａ ｓｃａｎｄｅｎｓ（Ｆｒａｎｃｈ．）Ｍａｘｉｍ〗根茎甲醇提取物的石油醚和波谱分析,分离出８个化合物,经理化常数和波谱分析,分别鉴定为：７－羧基贝壳杉烯内酯（１）,蒲公英赛烷醇（２）,桦木酸（３）,乌苏酸（４）,２α,３α,２３－三羟基乌苏－１２－烯－２８－酸（５０,２α３α２３－三羟基乌苏－１２,２０（３０）－二烯－２８０酸（６）,豆甾－４－烯－３,６－二酮（     

毛喉鞘蕊花的微量成分

从唇形科毛喉鞘蕊花全草的氯仿提取物分离到２个新的微量成分,鞘蕊花戊素和已素。基于光谱分析,鞘蕊花戊素和已 素的化学结构分别鉴定为１α,７β－二乙酰氧基－８,１３－环氧－６β羟基勒丹－１４烯－１１－酮（１）和７β－乙酰氧基－８,１３环氧－６β,α－二羟基勒丹－１４烯－１１－酮（２）。     

麻疯树根的化学成分研究

从麻疯树（Ｊａｔｒｏｐｈａ ｃｕｒｃａｓ Ｌ．）的根中分离到１３ 个化合物,经理化常数和波谱鉴定（ＩＲ、１Ｈ－ＮＭＲ、１３Ｃ－ＮＭＲ、ＥＩＭＳ和ＦＡＢＭＳ）分别为∶５α－豆甾烷－３,６－二酮（１）、川皮甙（２）、β－谷甾醇（３）、蒲公英脑（４）、２Ｓ－正二十四饱和脂肪酸甘油酯－１（５）、５－羟基－６,７－二甲氧基香豆素（６）、麻疯树酚酮Ａ（７）、麻疯树酚酮Ｂ（８）、６－甲氧基－７－羟基香豆素（９）、ｃａｎｉｏｊａｎｅ （１０）、３－羟基－４－甲氧基－苯甲醛（１１）、３－甲氧基－４－羟基苯甲酸（１２）和胡萝卜甙（１３）． 其中,化合物５ 为未见报道的新化合物,化合物１、２、９、１０、１１、１２ 为首次从该植物中分得,１０ 为含有过氧基团的二萜化合物． ７ 和８ 为一对四环二萜的立体异构体,并在碱中相互转化     

四川清风藤根皮中三萜成分的研究

从四川清风藤（Ｓａｂｉａ ｓｃｈｕｍ ａｎｎｉａｎａ Ｄｉｅｌｓ）的根皮分离到５ 个三萜化合物,根据理化常数、波谱分析及配合衍生物制备,分别鉴定为：３－氧,Δ１１,１３（１８）－齐墩果二烯（１）、３,１１－二氧,Δ１２－齐墩果烯（２）、３β－羟基,Δ１１,１３（１８）－齐墩果二烯（３）、３－氧,１１α－羟基,Δ１２－齐墩果烯（４）和３β,１１α－二羟基,Δ１２－齐墩果烯（５）。其中,４为新化合物     

香港坚木中的达玛烷型三萜

从楝科植物香港坚木的树吉中分得了４个新的达玛烷型三萜,基于详细的光谱分析及与同类化合物的光谱数据比较鉴定了其结构,分别命名为：２０Ｒ,２４Ｒ－表－２５－达玛烷烯－３－酮,１６β－羟基达玛烷－２０,２５－二烯－３－酮,２６－羟基达玛烷－２０,２４－二烯－３－酮和３β－乙酰基－７α,２１Ｓ,２５－三羟基－２１Ｓ,２３Ｒ－表－１（１１）－达玛烷烯。     

梨头霉11α—羟基化制备16β—甲基—11α,17α21—三烃基孕甾—1, …

选育到一株对１６β－甲基－１７α,２１－二羟基孕甾－１,４＝－二烯－３,２０－二酮（Ⅱａ）１１α－羟基化活性强的梨头霉Ａ２８菌株,并发现底物２１－乙酰化（Ⅱｂ）可明显提高１１α－羟工 能力。在适宜的转化条件下,１１ｂ投料浓度０．５％,产物１６β－基１１α,１７α,２１－三羟基孕甾－１,４－二烯－３,２０－二酮（Ⅲ）收率为７３％,结构经波谱分析确认。     

钩藤的三萜成分

从钩藤枝叶的乙醇提取物中分离得到５个三萜成分。经光谱鉴定。Ｉ为已知化合物：３β,６β。１８α－ｔｒｈｙｄｒｏｘｙｕｒｓ－１２－ｅｎ－２８－ｏｉｃ－ａｃｉｄ;Ⅱ为新化合物;３β,６β－ｄｉｈｙｄｒｏｘｙｕｒｓ－１２,１８（１９）－２８－ｏｉｃａｃｉｄ,命名为钩藤甙元Ａ     

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.