布渣叶中三萜和黄酮类成分的研究

从布渣叶(Microcos paniculata L.)的叶中分离得到10个化合物.通过光谱和波谱分析,分别鉴定为无羁萜(1)、阿江榄仁树葡糖苷Ⅱ(2)、山柰酚-3-O-β-D-[3,6-二(对羟基桂皮酰)]-葡萄糖苷(3)、山柰酚-3-O-β-D-葡萄糖苷(4)、异鼠李素3-O-β-D-葡萄糖苷(5)、异鼠李素3-O-β-D-芸香糖苷(6)、牡荆苷(7)、佛来心苷(8)、异佛来心苷(9)、异牡荆苷(10).10个化合物均为首次从布渣叶中分离得到.     

尖叶胡枝子黄酮类化学成分的研究

采用硅胶、凝胶和聚酰胺等柱层析及HPLC等方法对尖叶胡枝子[Lespedeza hedysaroides (Pall.) Kitag.]70%乙醇提取物中的黄酮类化学成分进行研究,共分离得到8个化合物,通过光谱和波谱分析,分别鉴定为荭草素(1)、牡荆苷(2)、异荭草素(3)、异牡荆苷(4)、槲皮素-3-O-β-D-葡萄糖苷(5)、木犀草素-7-O-葡萄糖苷(6)、6-xylopyranosylluteolin(7)、异杨梅树皮苷(8),其中化合物5～8为首次从尖叶胡枝子中分离得到.研究结果表明:碳苷黄酮(化合物1～4)是尖叶胡枝子黄酮类的主要成分,具有较好的药理活性,作为一种药用植物资源,尖叶胡枝子具有广阔的开发利用前景.     

云南透骨草的化学成分研究

从云南透骨草全草95%乙醇提取物中分离得到11个化合物,经波谱分析鉴定为山奈酚3-O-α-L-吡喃鼠李糖苷(1),番石榴苷(2),滇白珠甲苷(3),槲皮苷(4)(,-)-5’-甲氧基异落叶松脂醇9-O-β-D-木糖苷(5),五味子苷(6)(,–)-表儿茶素(7),异槲皮苷(8),金鸡纳素Ia(9),熊果酸(10)和2,5-双-(β-苯乙基)苯酚(11)。其中化合物1、2、9和11为首次从该植物中分得,化合物11是首次报导的天然产物。     

槐角化学成分及其抗骨质疏松作用研究

研究槐角的化学成分及其抗骨质疏松作用。利用硅胶柱、ODS反相硅胶柱、Sephadex LH-20凝胶柱和半制备型高效液相等色谱技术对槐角进行分离纯化,并结合化合物的理化性质和波谱数据确定化合物的结构。从槐角中分离得到15个化合物,分别为染料木素(1)、山萘酚(2)、鸢尾苷(3)、芒柄花苷(4)、α-鼠李异洋槐素(5)、鹰嘴豆芽素A-7-O-β-D-葡萄糖苷(6)、南酸枣苷(7)、thevetiaflavon(8)、香豌豆酚-7-O-β-D-葡萄糖苷(9)、山萘酚-7-O-β-D-葡萄糖苷(10)、槲皮苷(11)、山萘酚-3-O-β-D-槐糖苷(12)、染料木素-7,4'-双葡萄糖苷(13)、槲皮素-3-O-β-D-槐糖苷(14)、山萘酚-3-O-β-D-槐糖-7-O-α-L-鼠李糖苷(15)。其中化合物6~12、14为首次从该种植物中分离得到,化合物7、8、10、14为首次从该属植物中分离得到。对所分离的化合物进行了抗骨质疏松体外药理活性筛选,结果表明除化合物7和15以外,其他化合物均具有促进成骨细胞增殖作用。     

飞蛾藤中的新C30甾体类化合物

从毛叶飞蛾藤(Porana racemosa Roxb.)全草的95%乙醇提取物中分离并鉴定了11个化合物,其中一新的C30甾体化合物鉴定为(22E,24ξ)-24-正丙基胆甾-7,22-二烯-3β-醇(飞蛾藤素,1).其余10个已知化合物分别为东莨菪素(2)、东莨菪苷(3)、伞形华内酯(4)、β-D-甲基吡喃果糖苷(5)、丁香脂素4-O-β-D-吡喃葡萄糖苷(6)、斛皮素-3-O-β-D-吡喃葡萄糖苷(7)、斛皮素-3-O-α-L-吡喃鼠李糖苷(8)、异泽兰黄素(9)、山奈素-3-O-β-D-吡喃葡萄糖苷(10)和(E)-N-2-(2,3-二羟基苯基)乙基肉桂酰胺(11).     

算盘子的化学成分研究

对算盘子(Glochidion puberum)的化学成分进行研究.从其乙醇提取物的乙酸乙酯和正丁醇部位分离得到了9个化合物,根据化合物的理化性质和光谱数据鉴定其结构分别为:牡荆素(1)、β-D-吡喃半乳糖-(3→3)-O-β-D-吡喃半乳糖(2)、丁香脂素(3)、(Z)-3-已烯-D-吡喃葡萄糖(4)、(E)-2-已烯-D-吡喃葡萄糖(5)、4-O-乙基没食子酸(6)、没食子酸(7)、胡萝卜苷(8)、β-谷甾醇(9).     

维药洋甘菊化学成分及DPPH自由基清除活性研究

为对洋甘菊(Matricaria chamomilla L.)的化学成分进行分离纯化及化合物DPPH自由基清除的活性进行考察,本实验通过正、反相硅胶、Sephadex LH-20、半制备高效液相色谱,从洋甘菊中分离得到11个化合物,通过波谱方法进行鉴定结构为山萘酚-3-O-β-D-葡萄糖苷(1)、木犀草素-3′-O-β-D-葡萄糖苷(2)、6-羟基木犀草素-7-O-β-D-葡萄糖苷(3)、异槲皮苷(4)、5-羟基-4′,7-二甲基-6,8-二甲氧基黄酮(5)、槲皮素-3′-O-β-D-葡萄糖苷(6)、3-羟基苯甲醇(7)、1-(4-羟基苯基)乙烷-1,2-二醇(8)、2-(3-甲氧基-4-羟基苯基)-丙烷-1,3-二醇(9)、2-(4-羟基乙基)乙醇(10)、丁香酸(11),其中化合物1～3、5、7～11为首次从该植物中分离得到,经DPPH清除自由基活性筛选发现化合物1～3、5、6有着与对照组相当的DPPH自由基清除活性。     

阔鳞鳞毛蕨黄酮类化学成分的分离与鉴定

为研究阔鳞鳞毛蕨Dryopteris championii的化学成分,本研究利用硅胶、ODS、Sephadex LH-20柱层析及制备型高效液相等色谱分离技术对阔鳞鳞毛蕨地上部分的95%乙醇提取物进行分离纯化,从乙酸乙酯萃取部位分离得到13个黄酮类化合物,并通过现代光谱和文献对比的方法鉴定其结构分别为表儿茶素(1)、木犀草素(2)、柚皮素(3)、圣草酚(4)、槲皮素(5)、芹菜素(6)、山奈酚(7)、黄芪苷(8)、广寄生苷(9)、槲皮素-3-O-β-D葡萄糖苷(10)、牡荆素(11)、芹菜素-7-O-β-D-葡萄糖苷(12)、槲皮素-3-O-6-反式-对香豆酰基-β-D-葡萄糖-(1→2)-α-L-鼠李糖苷(13),包括1个黄烷醇、2个二氢黄酮、4个黄酮、6个黄酮醇。化合物1～13均为首次从该种植物中分离得到,其中6、8、9、11和13为首次从该属植物分离得到。     

昆仑雪菊黄酮类成分研究

采用大孔树脂、ODS RP-18和Sephadex LH-20柱从昆仑雪菊中分离得到7个黄酮类化合物,通过理化性质和波谱学方法鉴定化合物的结构,分别为:异奥卡宁7-O-β-吡喃葡萄糖苷(1)、栎草亭-7-O-β-D-吡喃葡萄糖苷(2)、马里苷(3)、奥卡宁(4)、木犀草素(5)、槲皮素(6)、8-羟基黄颜木素(7)。其中化合物2、5、6和7为首次从该植物中分离得到。     

枸骨叶的化学成分研究

采用溶剂提取和柱层析色谱分离,根据化合物理化性质和光谱数据鉴定其结构.结果从枸骨叶中分离得到9个化合物,分别为羽扇豆醇(1)、3,28-乌苏酸二醇(2)、熊果酸(3)、异鼠李黄素(4)、山奈酚-3-O-β-D-葡萄糖苷(5)、地榆苷Ⅰ(6)、槲皮苷-3-O-β-D-葡萄糖苷(7)、异鼠李素-3-O-β-D-葡萄糖苷(8)、冬青苷Ⅱ(9).化合物7和8为首次从冬青属植物中分离得到,化合物5为首次从该植物中分离得到,同时首次报道了化合物9的13CNMR数据.     

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.