牛心朴子中的三个新C21甾体配糖体

从宁夏产植物牛心朴子( Cynanchum komarovii Al. Iljinski.) 须根的乙醇提取物中分离并鉴定了4 个C₂₁ 甾体配糖体: 白前苷元C 3- O-β-D-吡喃葡萄糖基-(1→4 )-β-D-吡喃葡萄糖基-( 1→4-α-L-吡喃磁麻糖基-( 1→4 )-β- D-吡喃毛地黄毒糖基- (1→4 )-β- D-吡喃夹竹桃糖苷( 1) , 白前苷元A 3- O-β- D-吡喃葡萄糖基- (1→4 ) -β-D-吡喃葡萄糖基-(1→4 ) -α- D-吡喃夹竹桃糖基- (1→4 )-β- D-吡喃毛地黄毒糖基-(1→4 )-β- D-吡喃夹竹桃糖苷(2) , 白前苷元C 3- O-β-D-吡喃葡萄糖基-(1→4 )-β- D-吡喃葡萄糖基- (1→4 )-α- D-吡喃夹竹桃糖基-(1→4 ) -β-D-吡喃磁麻糖基-( 1→4 )-β- D-吡喃夹竹桃糖苷( 3) , 白前苷元A 3- O-β- D-吡喃葡萄糖基-(1→4 )-β-D-吡喃葡萄糖基-( 1→4 )-α- D-吡喃夹竹桃糖基- (1→4 ) -β-D-吡喃磁麻糖基- (1→4 )-β- D-吡喃夹竹桃糖苷( 4) , 分别命名为komaroside I (1) , komaroside J ( 2) , komaroside K ( 3) , komaroside L ( 4) , 除化合物1 外,其余化合物均为新化合物。     

滇产植物皂素成分的研究——Ⅹ.五指莲的两个新甾体皂甙(1)

从重楼属植物五指莲Paris axialis H.Li.根茎中分离到三个甾体皂甙,经化学降解,质谱,核磁共振谱分析,证明其中两个甙为新的化合物,即偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅰ)和24α-羟基偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)][α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖(Ⅲ);另一个鉴定为薯芋皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅱ)。     

金铁锁皂甙的研究

从金铁锁(Psammoslene tunicoides)根中分离到二个新的齐墩果烷型五环三萜皂甙Ⅰ、Ⅱ,经光谱测定和化学降解证明它们的化学结构为齐墩果烷-3α,16α-二羟基-12烯-23-酸-28-O-β-D-葡萄吡喃糖基(1—3)-β-D-葡萄吡喃糖基(1—6)-β-D-葡萄吡喃糖甙(Ⅰ)和齐墩果烷-3α,16α-二羟基-12烯-23-酸-28-O-β-D-葡萄吡喃糖基1—6[-β-D-葡萄吡喃糖基1—3]-β-D-葡萄吡喃糖甙(Ⅱ)。上述两个化合物的母核配基均为同一的物质,差异是糖的连接位置不相同。     

枸骨的化学成分

从枸骨(Ilex cornuta Lindl,ex paxt.)中分离得到20个化合物,鉴定了16个,分别为：枸骨甙1(Gougusidel,V)即坡摸酸3-β-O-O-L吡喃阿拉伯糖甙;枸骨甙2(Gouguside 2,Ⅵ)即3-β-O-D-吡喃葡萄糖基坡摸酸-β-28-O-D吡喃葡萄糖酯;枸骨甙3(Gouguside 3,Ⅶ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L吡喃葡萄糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯的类似物;枸骨甙4(Gouguside 5,ⅩⅦ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L-吡喃葡萄糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯;枸骨甙5(Gouguside 5,ⅩⅧ)即坡摸酸3-β-O-α-L-2’-乙酰氧基吡喃阿拉伯糖基-28-O-β-D-吡喃葡萄糖酯,枸骨甙6(Gouguside 6,ⅩⅪ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L-4-乙酰氧基吡喃阿拉伯糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯;枸骨甙7(Gouguside 7,ⅩⅩ)即3-β-O-α-L-吡喃阿拉伯糖基-28-O-β-D-吡喃葡萄糖酯;胡萝卜甙(daucostorol Ⅷ);2,4-二羟基苯甲酸(2,4-dihydroxybenzoicacid I);3,4-二羟基桂皮酸(3,4-dihyroxycinnamunic acid Ⅱ,Ⅳ);长链脂肪酸或醇5个(Longchain fatty acid Ⅲ,Ⅵ,Ⅶ,Ⅷ,ⅩⅣ)。在鉴定的16个化合物中,枸骨甙1、枸骨甙2、枸骨甙6和枸骨甙7为首次从枸骨中分离得到,枸骨甙3和枸骨甙4为新化合物。     

排风藤中皂苷类化学成分研究

从茄属植物排风藤的全草中分离得到了4个皂苷类化合物,经鉴定分别为:25R-螺甾-3-O-[β-D-吡喃木糖基-(1→3)]-O－β-D-吡喃葡萄糖基-(1→2)-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(1),5α,25R-螺甾-3-O-[β-D-吡喃木糖基-(1→3)]-O-β-D-吡喃葡萄糖基-(1→2)-O－β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(2),22α,25R-26-O-β-D-吡喃葡萄糖基-22-羟基-呋甾-△5-3β,26-二醇-3-O-β-D-吡喃葡萄糖基-(1→2)-O-[β-D-吡喃木糖基-(1→3)]-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃半乳糖苷(3),22α,25R-26-O-β-D-吡喃葡萄糖基-22-羟基-呋甾-△5-3β,26-二醇-3-O－β-D-吡喃葡萄糖基-(1→2)-O-β-D-吡喃葡萄糖基-(1→4)-O-β-D-吡喃葡萄糖苷(4).化合物1-4均为首次从排风藤中分离得到.     

油菜蜂花粉中皂苷化学成分的研究

油菜蜂花粉煮沸灭酶,减压蒸干,用80%乙醇提取,经AB-8大孔树脂、MCI柱和ODS反相柱层析柱分离,得到4个皂苷类化合物,通过理化方法、1H NMR、13C NMR等手段鉴定他们的化学结构,分别为:3,22-二羟基,3-O-β-D-葡萄糖-齐墩果烷(1)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果烷(2)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果酸(3)和3-O-β-D-葡萄糖-谷甾醇苷(4)。其中,皂苷1～3在油菜蜂花粉中首次报导。     

亮叶杨桐(石芽茶)中黄酮类成分的研究

从广西产亮叶杨桐(Adinandra nitida Merr.ex H.L.Li)中,分得三种黄酮类成分:Ⅰ、Ⅱ和Ⅲ。经IR、UV(位移诊断)、熔点、混熔点、薄层层析鉴定:Ⅰ为芹菜素(Apigenin);Ⅱ为芹菜素-5-0-α-L-吡喃鼠李糖基(1→4-6~(?)-乙酰基-β-D-吡喃葡萄糖吡;Ⅲ为芹菜素-5-0-α-L-吡喃鼠李糖基(1→4)-β-D-吡喃葡萄糖甙。     

无柄新乌檀中的配糖体

从无柄新乌檀乙醇浸膏的正丁醇部位分离得到7个已知配糖体化合物,经波谱分析为：喹诺酸-3-O-β-D-葡萄吡喃糖基(28→1)-β-D-葡萄吡喃糖酯(1),齐墩果酸-(28→1)-β-D-葡萄吡喃糖酯(2),熊果酸-(28→1)-β-D-葡萄吡喃糖酯(3),喹诺酸-3-O-β-D-葡萄吡喃糖基-(1→3)-6-去氧-β-葡萄吡喃糖苷(4),齐墩果酸-3-O-β-D-吡喃木糖基-(1→2)-β-D-葡萄吡喃糖基-28-O-β-D-葡萄吡喃糖酯(5),番木鳖甙(6),7-甲氧基-龙胆苦甙(7)。这些化合物均为首次从该属中分离得到。     

牛心朴子中三个新C21甾体配糖体

从宁夏产植物牛心朴子（Cymmehumkomarovii Al．IIjinski）须根的乙醇提取物中分离并鉴定了4个C21甾体配糖体：白前苷元C 3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α-L-吡喃磁麻糖基-（1→4）-β-D-吡喃毛地黄毒糖基-（1→4）-β—D-吡喃夹竹桃糖苷（1）,白前苷元A 3-O-β-D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α-D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃毛地黄毒糖基-（1→4）-β-D-吡喃夹竹桃糖苷（2）,白前苷元C3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α—D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃磁麻糖基-（1→4）-β-D-吡喃夹竹桃糖苷（3）,白前苷元A3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α—D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃磁麻糖基-（1→4）-β-D-吡喃夹竹桃糖苷（4）,分别命名为komarosideI（1）,komarosideJ（2）,komarosideK（3）,komarosideL（4）,除化合物1外,其余化合物均为新化合物。     

小花棘豆化学成分的研究

从有毒植物小花棘豆(Oxytropis glabra DC.)的地上部分分离得到10种化合物,经光谱分析及理化常数测定,分别鉴定为槲皮素(Ⅰ)、山奈酚(Ⅱ)、3′,7-二羟基-2′,4′-二甲氧基-异黄烷(Ⅲ)、山奈-7-O-α-L-鼠李吡喃糖甙(Ⅳ)、山奈酚-3-O-β-D-葡萄吡喃糖甙(Ⅴ)、山奈酚--O-β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖甙(Ⅵ)、山奈酚-3-O-β-D-葡萄吡喃糖-7-O-β-D-葡萄吡喃糖甙(Ⅶ)槲皮素-3-O-β-D-葡萄吡喃糖甙(Ⅷ)、杨梅树皮甙(Ⅺ)和3-O-[α-L-鼠李吡喃糖基(1→3)-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄吡喃糖醛酸基]-黄豆醇B(Ⅹ)。上述成分均为首次从该植物中分得。化合物Ⅹ为新化合物。     

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.