钩枝藤化学成分研究

采用95%乙醇提取,石油醚、乙酸乙酯萃取分部,利用反复硅胶柱和凝胶柱色谱进行分离、纯化,根据波谱技术鉴定结构,研究钩枝藤茎中的化学成分。结果发现:分离得到5个已知二氢黄烷类化合物(-)-表儿茶素-3-没食子酸酯(1)、3,3',5,5',7-五羟基黄烷(2)、(-)-儿茶素(3)、(-)-表儿茶素(4)、(-)-表没食子酸儿茶素(5)和1个酚类化合物(3,5-二甲氧基-4-羟基苯酚)-1-O-β-D-(6-O-没食子酸)葡萄糖苷(6)。其中化合物1、2、4-6均为首次从该植物分离得到。     

头序瓜馥木化学成分研究

综合运用硅胶柱色谱、反相硅胶柱色谱和Sephadex LH-20凝胶柱色谱以及制备型高效液相等色谱方法对番荔枝科瓜馥木属植物头序瓜馥木Fissistigma retusum枝叶中的化学成分进行了系统研究,从其枝叶的95%乙醇提取物中分离鉴定了12个化合物,根据化合物的理化性质及其波谱学数据将它们分别鉴定为:原儿茶酸乙酯(1)、(S)-甲氧基-(3,5-二甲氧基-4-羟苯基)乙二醇(2)、2-顺式-4-反式-脱落酸(3)、山萘酚-3-O-а-L-吡喃阿拉伯糖苷(4)、柚皮素(5)、香树素(6)、圣草酚(7)、(2R,3S)-5,7,3'-三甲氧基表儿茶素(8)、5,6,8-三甲氧基-7-羟基二氢黄酮(9)、丁香脂素(10)、epiyangambin(11)、seartemin(12)。其中化合物1和2为2个酚酸类化合物,3和4为2个萜类化合物,5~9为5个黄酮类化合物,化合物10~12为3个木脂素类化合物,化合物1~12为首次从番荔枝科瓜馥木属植物中分离得到。     

重唇石斛地上部分化学成分及其生物活性研究

为了解重唇石斛(Dendrobium hercoglossum)的化学成分,利用硅胶、Sephadex LH-20柱色谱和半制备高效液相色谱等方法,从其地上部分分离了14个化合物,经波谱分析,其结构分别鉴定为：3,4,5-三甲氧基苯酚(1)、3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-propan-1-one (2)、methyl 3-(p-hydroxyphenyl) propionate (3)、justiciresinol (4)、榕醛(5)、异落叶松脂素(6)、threo-2,3-bis-(4-hydroxy-3-methoxyphenyl)-3-methoxypropanol (7)、(+)-松脂素(8)、aloifolⅠ(9)、dendrocandin T (10)、3-甲氧基-4-羟基苯丙酮(11)、1,3,5-三甲氧基苯酚(12)、香草醇(13)和丁香脂素(14),其中化合物1～12,14均为首次从重唇石斛中分离得到,化合物7、10和14为首次从石斛属植物中分离得到。化合物4、8和10具有显著的酪氨酸酶抑制活性,IC_...     

小花清风藤叶的化学成分研究

对于小花清风藤的化学成分和药理作用的研究目前较少报道,为了阐明小花清风藤的物质基础,该研究对小花清风藤(Sabia parviflora)的干燥叶,采用反复硅胶柱色谱、Sephadex LH-20柱色谱、制备薄层色谱及重结晶等手段进行分离纯化,运用化学分析和波谱学方法鉴定化合物的结构。结果表明:从小花清风藤干燥叶的甲醇超声提取物中进行分离共得到12个化合物,分别为N-反式阿魏酰酪胺(1)、N-顺式阿魏酰酪胺(2)、N-反式-对-香豆酰酪胺(3)、N-顺式-对-香豆酰酪胺(4)、N-反式-对-香豆酰章鱼胺(5)、N-顺式-对-香豆酰章鱼胺(6)、阿魏酸(7)、芹菜素(8)、木犀草素(9)、咖啡酸(10)、5-氧阿朴菲碱(11)、齐墩果酸(12)。其中,化合物2、4-9为首次从清风藤属植物中分离得到,化合物1、3、10为首次从该植物中分离得到。     

无梗五加根中苯丙素类化合物的研究

从无梗五加(Acanthoparax sessiliflorus( Rupr.et Maxim.)Seem.)根70％乙醇提取物的乙酸乙酯层中提取分离得到8个苯丙素类化合物.经理化和波谱分析鉴定为(+)-表芝麻脂素(1)、(-)-芝麻脂素(2)、赛菊芋黄素(3)、洒维宁(4)、咖啡酸甲酯(5)、对羟基桂皮酸(6)、(-)-丁香脂素(7)、(+)-松脂索(8).化合物8是首次从五加科植物中分离得到,化合物1和5是首次从五加属植物中分离得到,化合物3、6和7是首次从该植物中分离得到.     

海南栽培肾茶的化学成分研究

为了解肾茶(Clerodendranthus spicatus)的化学成分,从海南栽培肾茶地上部分分离得到11个化合物,经波谱分析分别鉴定为:吐叶醇(1)、丁香脂素(2)、3,4-二羟基苯乙醇(3)、甜橙素(4)、5,6,7,4′-四甲氧基黄酮(5)、5-羟基-6,7,3′,4′-四甲氧基黄酮(6)、6-羟基-5,7,4′-三甲氧基黄酮(7)、5-羟基-6,7,3′,4′-四甲氧基黄烷酮(8)、3,3′,5-三羟基-4′,7-二甲氧基-二氢黄酮(9)、松脂素(10)和熊果酸(11)。化合物3、9和10为首次从肾茶中分离得到。对化合物1~6进行活性测试,结果表明化合物3~5对乙酰胆碱酯酶具有一定的抑制活性。     

白花牛角瓜根部的化学成分研究

从萝藦科植物白花牛角瓜的根部中分离得到了8个化合物,经波谱分析鉴定为1-O-methyl-guaiacylglyc-erol(1)、ω-hydroxypropioguaiacone(2)、C-Veratroylglycol(3)、Ficusol(4)、(+)-丁香脂素(5)、9α-hydroxypinoresinol(6)、对羟基苯甲醛(7)、尼克酰胺(8)。以上化合物皆为首次从该种中分离得到。     

水栀子果实化学成分研究(Ⅱ)

利用多种色谱学技术从水栀子Gardenia jasminoides var.radicans果实中分离得到11个化合物,并应用多种波谱学手段将它们的结构分别鉴定为Z-甲基-6-氧代-Z,4-庚二烯酸O-β-D-龙胆二糖苷(1)、jasminoside O(2)、3,5-二甲氧基-4-羟基-苯甲醛(3)、5-羟甲基糠醛(4)、(5R,2E)-5-羟基-2-甲基-庚-2-烯-1,6-二酮(5)、1-O-对香豆酰基葡萄糖苷(6)、6,7-二甲氧基-4-羟基-1-萘甲酸(7)、10-O-E-p-香豆酰京尼平苷酸(8)、6'-O-反式-肉桂酰基京尼平龙胆二糖苷(9)、丁香脂素(10)、松脂素(11)。以上化合物均为首次从该植物中分离得到。     

蝴蝶花的化学成分研究

对鸢尾科鸢尾属植物蝴蝶花全草进行化学成分和生物活性研究。通过正相硅胶、Sephadex LH-20以及反相HPLC柱等等色谱方法对蝴蝶花的化学成分进行分离纯化,应用谱学技术鉴定化合物的结构。从蝴蝶花95%乙醇提取物中分离得到18个化合物,分别鉴定为:(+)-(7S,8R,7'E)-4-hydroxy-3,5'-dimethoxy-4',7-epoxy-8,3'-neolign-7'-ene-9,9'-diol 9'-ethyl ether(1)、丁香脂素(2)、erythro-guaiacylglycerol-β-O-4'-coniferylether(3)、threo-guaiacylglycerol-β-O-4'-coniferylether(4)、4-O-β-d-(6-O-vanilloylglucopyranosyl)vanillic acid(5)、4-[6-O-(4-hydroxy-3,5-dimethoxybenzoyl)-β-d-glucopyranosyloxy]-3-methoxybenzoic acid(6)、藏黄连新苷B(7)、belalloside B(8)、藏黄连新苷A(9)、茶叶花宁(10)、sakuranetin(11)、鼠李柠檬素(12)、鸢尾甲黄素B(13)、染料木素(14)、5,7,4'-三羟基-6,8-二甲氧基异黄酮(15)、野鸢尾苷元(16)、8-羟基鸢尾苷元(17)、3'-O-methylorobol(18)。其中,化合物1~18均为首次从该种植物中分离得到。化合物1、2、5、6、15为首次从该属植物中分离得到。对所分离得到的化合物进行了保肝、抗炎、抗氧化等体外药理活性筛选。     

旋覆花的化学成分研究(英文)

通过应用硅胶柱色谱,Sephadex LH-20柱色谱,以及高效液相制备色谱等手段,从旋覆花地上部分分离纯化得到10个化合物,再通过光谱学方法,并结合化合物的理化性质鉴定为泽兰内酯(1)、7-羟基香豆素(2)、瑞香素(3)、东莨菪素(4)、蟛蜞菊内酯(5)、枸橼苦素(6)、杜仲树脂酚(7)、丁香酸(8)、香草酸(9)和异丁香酸(10)。化合物1～10均为首次从旋覆花属植物中分离得到。     

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.