柿中具有△^12熊果烯骨架的五环三萜类化合物

柿（Diospyros kaki L.f.）的果实中分离出5个化合物,通过IR、MS、^1HNMR、^13CNMR鉴定,确定为：熊果辛酯（octyl yursolate）,△^5,6－3－（2′－甲在戊酰氧在）－熊果酸环己酯〔△^5,6－3－（2′－methyl pentanoyl）-ursolic acid cyclohexy ester〕,β－香树脂醇己醚（β－amyrin hexyl ether）,△^6,7－香树素（△^6,7－amyin）和熊果甲酯（methyl ursolate）。     

弯蕊开口箭中的新甾体配糖体

从百合科植物弯蕊开口箭（Tupistra Hook,f．）的根茎中分离得到4个新的甾体配糖体,分别命名为弯蕊苷（wattoside)B-E(1-4),其中,3个多羟基呋甾型配糖体,另1个为强心苷,经化学降解和光谱分析,其化学结构分别鉴定为：22－0－甲基－25（R,S）,－呋甾烷－1β,3β,4β5β,22ξ,26β－六醇－26－O－β－D－葡萄吡喃糖苷（1）：22－O－甲基－26－O－β－D-葡萄吡喃糖基－25（S）－呋甾烷－5－烯－β,3β,22ξ,26β－甲醇－3－0－[O-β-D-葡萄吡喃糖基（1－4）]－β－D-半乳吡喃糖苷（2）;22－0－甲基－25（S)-呋甾烷－1β,2β,3β,4β,5β,22,26β－七醇－26－O-β－D－葡萄吡喃糖苷（3）和夹竹桃苷元－3－O－[O-β-D-葡萄吡喃糖基（1－2）]－α－L－鼠李吡喃糖苷,弯蕊苷E为开口箭属植物中首次分离到的强心苷。     

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。     

四方蒿的化学成分

从唇形科植物四方蒿（Elsholtzia blanda (Benth.)Benth.)中分离得到9个化合物,用光谱分析、化学方法及与已知化合物对照,分别鉴定为：5,6－二氢－6－苯乙类吡喃－2酮（1）、木栓桐（2）、4－羟基－3－甲氧基苯乙烯（3）、5,2′－二甲氧基－6,7－二氧亚甲基双氢黄酮（4）、5－羟基07－甲氧基－6－O[α－L－鼠李糖（1→2）－β－D－岩藻糖]黄桐甙（5）,5,5′－二羟基－7－乙酰氧基6,8,3″,3″－四甲基吡喃（3′,4′）黄酮（6）、5,5′－二羟基－5－（α－甲基）丁酰氧基－6,8,3″,3″－四甲基吡喃（3′,4′）黄酮（7）、5,5′－二羟基－6,7－二氧亚甲基－8,3″,3″－三甲基吡喃（3′,4′）黄酮（8）和丁香酸葡萄糖甙（9）。其中,6、7、8为新化合物,分别命名为四方蒿素Ⅰ、Ⅱ和Ⅲ。     

抱茎獐牙菜的San酮甙和黄酮甙

从龙胆科植物抱茎獐牙菜（Swertia franchtiana H.Smith)中分得3种San酮甙,1种黄酮甙和1种三萜酸,通过光谱和化学等方法,分别鉴定为当药醇甙,当药黄素,芒果甙,1－O－[β－D－吡喃木糖－（1－6）－β－D－吡喃葡萄糖],－3,5－二甲氧基San酮（XI）和齐墩果酸,其中晶XI为一新化合物。     

抱茎獐牙菜的San酮甙和黄酮甙

从龙胆科植物抱茎獐牙菜（Swertia franchtiana H.Smith)中分得3种San酮甙,1种黄酮甙和1种三萜酸,通过光谱和化学等方法,分别鉴定为当药醇甙,当药黄素,芒果甙,1－O－[β－D－吡喃木糖－（1－6）－β－D－吡喃葡萄糖],－3,5－二甲氧基San酮（XI）和齐墩果酸,其中晶XI为一新化合物。     

无患子中两个新的大戟烷型三萜皂甙

从无患子科无患子（Sapindus mukorossi Gaertn.)根中分离到两个新的大戟烷型三萜皂甙SapimukosideA（1）和SapimukosideB（2）。运用波谱和化学方法鉴定它们的结构为3－O－α-L鼠李吡喃糖基－（1→2）-[α-L－阿拉伯吡喃糖基－（1→3）]－β－D－葡萄吡喃糖基－21,23R－epoxyl tirucall-7,24R-diene-3β,21-diol(1)和3－O－α-L－鼠李吡喃糖基－（1→6）－β-D-葡萄吡喃糖基21,23R-epoxyl tirucall-7,24R-diene-3β,21-diol(2)。     

茜草乔木酮乙和丙的结构

从小红参（Ｒｕｂｉａｙｕｎｎａｎｅｎｓｉｓ）中分离鉴定了２个新的乔木烷型三萜,分别命名为茜草乔木酮乙和丙（ｒｕｂｉａｒｂｏｎｏｎｅＢ,Ｃ）。用光谱和化学方法证明它们的结构分别为：７β,１９α,２８－三羟基乔木－９（１１）－烯－３－酮和２８－乙酰氧基－７β,１９α－二羟基乔木－９（１１）－烯－３－酮。     

鹿角蕨化学成分的研究

从鹿角蕨（Platycerium wallichii Hook.)的干燥叶中分离得到七个成分,利用UV、IR、^13C-NMR、^1H-NMR、MS等光谱方法鉴定出它们的结构,分别为β－谷甾醇（I）、谷甾醇β-D-吡喃葡萄糖苷（Ⅱ）、2－propenoic acid,3-[2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-5-benzofuramyl]-(Ⅲ）、松脂素（Ⅳ）、松脂素－4′－O－β－D－葡萄糖苷（Ⅴ）、2,5－二羟基苯甲酸甲酯（Ⅵ）、槲皮素3－O－β－吡喃半乳糖苷（Ⅶ）。七个成分均为首次从该种植物中获得。     

北五味子的水溶性化学成分

从北五味子（Schisandra chinensis）果实的水溶性部位得到8个已知化合物,经波谱分析确定其结构分别为：原儿茶酸（protocatechuic acid 1）,奎尼酸（quinic acid）,柠檬酸单甲酯（2－methyl citrate,3),5－羟甲基－2－糠醛（5-hydroxymethyl-2-furancarboxaldehyde 4),4-(3′－甲氮基－4′－羟基－苯基）－2－丁酮－4′-O-β-D0吡喃葡萄糖甙(zingerone glucoside 5),2－异丙基－5－甲基－1,4－苯二酚1－O－β－D－吡喃葡萄糖甙（thymoquinol 2-glu-coside 6),2－甲基－5－异丙基－1,4－苯二酚1－O－β－D－吡喃葡萄糖甙（thymoquinol 5-glu-coside 7)和胡萝卜甙（daucosterol 8）。     

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.     

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     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

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.     

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).     

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.