中国广西红树林植物海漆的化学成分研究

用硅胶柱层析和凝胶柱层析对红树林植物海漆(Excoecaria agallochaL.)的乙酸乙酯提取物进行分离纯化,从中分离得到9个化合物;通过波谱学数据它们分别鉴定为kayadiol(1)、8(14),15-isopimaradiene-7α,18-diol(2)5、,11-epoxy-9-hydroxy-7-megastigmen-3-one(3)、annuionone E(4)、28,30-dihydroxy-lup-20(29)-ene-3-one(5)、mes-sagenic acid G(6)、3,β24-dihydroxy-12-oleanen-28-oic acid(7)s、yringaresinol(8)、ethyl gallate(9)。这些化合物均为首次从该植物中分离得到。     

香樟叶化学成分的研究

采用硅胶色谱柱层析、聚酰胺色谱柱层析、制备薄层色谱及其它分离手段从香樟叶(Cinnamomum camphora Leaves)70%乙醇提取中分离得到9个化合物,根据化合物理化性质和波谱数据分别鉴定为:邻苯二甲酸二丁酯(1)、l-细辛脂素(2)、(8R,8'R)-3,3',4,4'-四甲氧基-9-氧代-8-8',9-O-9'-木脂素(3)、槲皮素-3-Ο-β-D-葡萄糖苷(4)、山奈酚-3-O-β-芸香糖苷(5)、山柰酚-3-O-α-L-吡喃鼠李糖苷(6)、槲皮素3-Ο-α-L-鼠李糖苷(7)、芦丁(8)、异鼠李素-3-O-β-芸香糖苷(9)。其中化合物1,2,6和9为首次从该种植物叶中分离得到。     

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.     

一株秋茄内生真菌Colletotrichum sp. SCSIO KcB3-2的次级代谢产物研究

对红树植物秋茄内生真菌Colletotrichum sp. SCSIO Kc B3-2的次级代谢产物进行研究,利用硅胶柱层析,中压ODS反相柱层析,半制备高效液相色谱仪等分离手段对其大米发酵产物进行分离纯化,利用核磁共振、质谱等波谱学手段并结合其理化性质及文献数据鉴定了14个单体化合物的结构:对羟基苯甲醛(1),2-(4-羟苯基)乙醇(2),2-(4-羟苯基)乙酸乙酯(3),2-羟基-2-(4'-羟基苯基)乙醇(4),2-甲氧基-2-(4'-羟基苯基)乙醇(5),苯乙二醇(6),2-氨基-3-苯基-1-丙醇(7),对羟基苯乙酸甲酯(8),2-(2-羟基乙基)苯酚(9),3-chlorogentisyl alcohol (10),4-hydroxymellein (11),diaporthin (12),环(L-苯丙-L-亮)二肽(13),环(D-苯丙-L-异亮)二肽(14)。化合物3～14均为首次从红树植物秋茄内生真菌中分离得到。     

黄桐枝叶的化学成分研究

为研究黄桐(Endospermum chinense Benth.)的化学成分,运用柱层析等分离纯化方法从黄桐枝叶中分离得到13个化合物:pubinernoid A(1)、(E)-linalool-1-oic acid(2)、(+)-去氢催吐萝芙木醇(3)、3α-hydroxy-5,6-epoxy-7-megastigmen-9-one(4)、齐墩果酸(5)、3-羰基齐墩果酸(6)、3-oleana-9(11),12-dien-28-oic acid(7)、甘五酸(8)、altissimanin C(9)、7-羟基-β-谷甾醇(10)、丁香脂素(11)、ficusesquilignan A(12)、ficusesquilignan B(13)。其中化合物7为新天然产物,化合物1~4、8~13为首次从该属植物中分离得到。     

木槿的化学成分研究

为了解木槿(Hibiscus syriacus)茎的化学成分,采用MCI-gel中压柱层析、硅胶柱层析、Sephadex LH-20凝胶柱层析和高效液相色谱等色谱方法,从木槿茎85%乙醇提取物中分离得到13个化合物。根据理化性质和波谱数据,其结构分别鉴定为methyl 4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl) ethyl] sinapate (1)、2,6,2′,6′-四甲氧基-4,4′-二(2,3-环氧-1-羟基丙基)二苯(2)、3,4,5-三甲氧基肉桂酸甲酯(3)、3,4-二甲氧基肉桂酸甲酯(4)、对羟基肉桂酸甲酯(5)、咖啡酸甲酯(6)、阿魏酸甲酯(7)、丁香脂素(8)、clemaphenol A (9)、(E)-3-hydroxyanetholeβ-D-glucopyranoside (10)、荭草苷(11)、木犀草素(12)和芹菜素(13)。其中化合物1～10为木脂素类,化合物11～13为黄酮类,化合物1为新天然产物,化合物1～12为首次从该植物中分离得到。采用MTS法检测,40μmol/L的化合物1～10对人白血病HL-60细胞和人肺癌A-549细胞株体外生长均未显示出较好的抑制活性。     

球药隔重楼的化学成分研究(英文)

采用硅胶柱层析、大孔吸附树脂、ODS柱层析、Sephadex LH-20和RP-C18柱层析等技术中分离得到8个化合物。通过波谱学数据和已知化合物数据比较,分别鉴定为β-谷甾醇(1),β-蜕皮激素(2),Paris SaponinsⅤ(3),Paris SaponinsⅠ(4),Paris SaponinsⅡ(5),Paris SaponinsⅦ(6),Paris Saponins H(7)和Paris SaponinsⅥ(8)。化合物1～8均为首次从球药隔重楼中分离得到。     

马槟榔种仁化学成分研究

对生长于云南文山的山柑科山柑属植物马槟榔种仁的化学成分进行分离鉴定。通过硅胶、MCI和Sephadex LH-20柱层析、分离纯化,结果分离得到8个化合物,运用现代波谱技术分别鉴定为:1-methoxy-3-indoleformic acid(1)、恶唑烷-2-硫酮(2)、O'-ethyl-1-β-D-arabinofuranosyluracil(3)、腺嘌呤核苷(4)、阿洛酮糖腺苷(5)、ethylβ-D-fructofuranoside(6)、1-β-D-psicofuranosyluracil(7)、尿嘧啶核苷uridine(8)。化合物1、3、7是新的天然化合物。化合物4、5、6为首次从马槟榔植物中分离得到。     

珍珠菜的化学成分研究(英文)

从珍珠菜(Lysimachia clethroidesDuby)的70%丙酮提取物中分离得到11个化合物,经理化性质及波谱数据分析分别鉴定为23-羟基乌苏酸(1)、Isotachioside(2)、对羟基苯甲酸(3)、3-甲氧基-4-羟基苯甲酸(4)、原儿茶酸(5)、3,5-二羟基苯甲酸(6)、甲基-α-D-呋喃果糖苷(7)、尿苷(8)、β-谷甾醇(9)、胡萝卜苷(10)和齐墩果酸(11)。化合物1、2、4、7和8为首次从该属植物中分离得到,化合物3、5、6、9~11为首次从该种植物中分离得到。     

芒果叶的化学成分研究

从芒果(Mangifera indica L.)叶中分离得到11个化合物,通过波谱数据分析分别鉴定为:芒果苷(1)、高芒果苷(2)、槲皮素(3)、没食子酸(4)、原儿茶酸(5)、没食子酸甲酯(6)、lingueresinol(7)、dihydrodehydrodiconiferyl alcohol (8)、1,3,6,7-tetrahydroxyxanthone(9)、5,7,3',4’-tetrahydroxy-2-methoxy-3,4-flavandione3-hydrate(10)、1-(4-hydroxy-3-methoxyphenyl)-2-[4-(w-hydroxypropyl-2-methoxy)-phenoxyl]-propane-l,3-diol(11).其中化合物7、8、10、11为首次从该植物中分离得到,化合物10的波谱数据为首次报道.     

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.