蜡菊花的化学成分研究

从菊科植物蜡菊(Helichrysum bracteatumVent)花的乙醇提取物中分离出11个化合物,经波谱分析鉴定为subscandenin(1),江户樱花苷(2),圣草素5-O-β-D-葡萄吡喃糖苷(3),pyracanthoside(4),槲皮素(5),木犀草素(6),柯伊利素(7),异荭草素(8),咖啡酸(9),piperitol(10),4-hydroxymethyl-1-methoxycarbonylazulene(11)。这些化合物均为首次从该植物中分离得到。     

类芒齿黄芪地下部分化学成分研究

为了解类芒齿黄芪( Astragalus camptodontoides)主要化学成分,从其地下部分甲醇提取物的乙酸乙酯部位分离出19个单体化合物,通过现代波谱分析及理化性质等手段分别鉴定为异补骨脂黄酮(1),4′-hydroxy-isolonchocarpin (2),5-去氧山豆根黄酮(3),shinflavanone (4),khonklonginols H (5),4′-O-methylpreglabridin (6),3′-hydroxy-4′-O-methylglabridin (7),4′-O-methylglabridin (8),8-prenyl-phaseollinisoflavan (9),xambioona (10),光甘草酚(11),粗毛甘草素H (12),methylnissolin (13),邻苯二甲酸异丁酯(14),邻苯二甲酸丁酯异丁酯(15),β-谷甾醇(16),胡萝卜苷(17),齐墩果酸(18),(2S,3S,4R,9E)-1,3,4-trihydroxy-2-[(2′R)-2′- hydr-oxytetraco-sanoylamino]-9-octadecene (19)。化合物1~19均为首次从该植物中获得,化合物1~7为首次从黄芪属(Astraga-lus)植物中分离得到。     

艾纳香化学成分的研究

从艾纳香(Blumea balsamifera DC.)中分离得到12个化合物,通过理化性质和波谱数据分析分别鉴定为;商路素(1),花椒油素(2),2,4-二羟基-6-甲氧基苯乙酮(3),5,7-二羟基色原酮(4),金丝桃苷(5),异槲皮苷(6),3′,4′,5,7-四羟基-3-甲氧基黄酮(7),槲皮素(8),槲皮素-3′-甲氧基-3-O-β-D-半乳吡喃糖苷(9),4′,5,7-三羟基-3,3′-二甲氧基黄酮(10),3,5,7-三羟基-3′,4′-二甲氧基黄酮(11),木犀草素(12).其中,化合物3-7和9- 11为首次从该属植物中分离得到.     

木荷茎皮化学成分研究

综合使用硅胶柱色谱、HP20大孔树脂柱色谱、ODS反相柱色谱及Sephadex LH-20凝胶柱色谱等色谱技术对木荷(Schima superba)茎皮进行分离纯化,并根据化合物理化性质以及应用MS、NMR技术对分离得到的化合物进行结构鉴定。从木荷中分离得到9个化合物,分别鉴定为三十烷酸(1)、棕榈酸(2)、Dodecanoic acid(3)、松脂素(4)、槲皮素(5)、山柰酚(6)、Americanin A(7)、槲皮素-3-O-β-D-葡萄糖苷(8)及槲皮素-3-O-α-L-鼠李糖苷(9)。化合物1～4 为首次从木荷中分离得到,化合物5、7、9 为首次从木荷属植物中分离得到。     

白叶香茶菜中的紫罗兰酮衍生物

从白叶香茶菜Isodon leucophyllus(Dunn)Kudo地上部分的丙酮提取物中,分离得到1个新的紫罗兰酮类化合物和6个黄酮类化合物,经IR,UV,MS,NMR波谱数据分析,其结构分别确定为：13—羧基布卢姆醇C(1),5,7,3′,4′—四甲氧基黄酮(2),线蓟素(3),5—羟基—6,7,3′,4′—四甲氧基黄酮(4),3′—羟基—5,7,8,4′—四甲氧基黄酮(5),异甜橙素(6)和异槲皮素(7)。其中,化合物2—7均为首次从该植物中得到。     

艾纳香中的黄酮类化合物及其抗氧化与α-葡萄糖苷酶抑制活性研究

本文对艾纳香Blumea balsamifera DC.叶中的黄酮类成分及其抗氧化与α-葡萄糖苷酶抑制活性进行了研究。从艾纳香叶中分离得到9个黄酮类化合物,分别鉴定为:4'-甲氧基二氢槲皮素(1),柽柳黄素(2),3,3'-二甲氧基槲皮素(3),7,4'-二甲氧基二氢槲皮素(4),(2α,3β)-二氢鼠李素(5),艾纳香素(6),sterubin(7),enodicytol(8),二氢槲皮素(9)。化合物3、5、8为首次从艾纳香中分离得到。分别用DPPH法和PNPG法筛选化合物的抗氧化活性及α-葡萄糖苷酶抑制活性。结果表明化合物2、5~9表现出强抗氧化活性;化合物1~3、5、9表现有较高的α-葡萄糖苷酶抑制活性。该结果为艾纳香的品质评价和深度开发利用提供了理论依据。     

构树皮中具有α-葡萄糖苷酶抑制活性的成分

本文报道构树皮中α-葡萄糖苷酶抑制剂的分离鉴定。构树皮的乙醇浸膏通过溶剂萃取以及各种柱层析方法分离纯化得到6个化合物,通过波谱学方法鉴定为:broussonetine A(1),broussonetinine A(2),brous-sonetinine B(3),黑立脂素苷(liriodendrin)(4),butyrospermyl acetate(5)以及胡萝卜苷(6)。所有化合物均首次从构树中分离得到,其中1~3具有较强抑制α-葡萄糖苷酶的活性,IC50有分别为0.530、0.445和0.460mg/mL。     

尾叶香茶菜水溶性部位化学成分研究

采用XAD16N大孔树脂、HW-40C凝胶柱和硅胶柱等色谱手段,从长白山产尾叶香茶菜甲醇提取物的水溶性部位中纯化得到山柰酚-3-O-芸香糖苷(1)、芦丁(2)、异槲皮苷(3)、槲皮素-7-O-鼠李糖苷(4)、金樱子皂苷A(5)、β-胡萝卜苷(6)、咖啡酸(7)、槲皮素(8)和熊果酸(9),其中化合物1,4,5,7,8为首次从尾叶香茶菜中分离得到,化合物1和5为首次从该属中分离得到。     

艾纳香黄酮类化学成分的研究(英文)

从艾纳香(Blumea balsamiferaDC.)的地上部分中分离得到13个黄酮类化合物,经鉴定分别为5,7-二羟基-3,3′,4′-三甲氧基黄酮(1),3,5,3′,4′-四羟基-7-甲氧基黄酮(2),4,2′,4′-三羟基双氢查尔酮(3),儿茶素(4),阿亚黄素(5),davidioside(6),二氢槲皮素-7,4′-二甲醚(7),艾纳香素(8),二氢槲皮素-4′-甲醚(9),3,5,3′-三羟基-7,4′-二甲氧基黄酮(10),5,7,3′,5′-四羟基二氢黄酮(11),木犀草素(12),槲皮素(13)。其中化合物1和3~6为首次从该植物中分离得到。     

新疆甘草化学成分研究

从新疆甘草(GlycyrrhizauralensisFisch.)根中分离得到5个化合物,分别鉴定为:槲皮素(1)、甘草次酸(2)、阿魏酸(3)、5,7,3′,4′-四羟基-7-葡萄糖基二氢黄酮醇(4)、8,5′-二羟基3′α-鼠李糖黄酮(5)。其中化合物4,5为首次从该植物中分离得到。     

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.