南丹参三萜类化学成分的研究

为研究南丹参根中三萜类化学成分,该文采用95%乙醇浸泡提取,依次应用D101大孔吸附树脂、MCI、硅胶柱色谱、ODS及反相高效液相色谱方法进行分离纯化,根据理化性质及波谱数据鉴定其化合物的结构。结果表明:从南丹参根提取物中分离得到9个化合物,分别鉴定为齐墩果酸(1)、2α,3α-二羟基-12-烯-28-齐墩果酸(2)、乌苏酸(3)、2α,3α-二羟基-12-烯-28-乌苏酸(4)、2α,3β-二羟基-12-烯-28-乌苏酸(5)、2α,3β,19α-三羟基-12-烯-28-乌苏酸(6)、2α,3β,24-三羟基-12-烯-28-乌苏酸(7)、psiguanin A(8)、正十六烷酸(9)。化合物1-9为首次从该植物中分离得到。     

白透骨消化学成分的研究

采用乙醇提取,硅胶柱反复层析的方法,从白透骨消[Glechoma biondiana (Diels) C.Y.Wu et C.Chen]全草的乙酸乙酯部分分离了11个化合物,利用现代波谱技术(MS,1H-NMR,13C-NMR,DEPT)以及与文献对照的方法鉴定了这些化合物的结构,分别为2α-羟基乌苏酸(1)、2α,3α-二羟基乌苏-12-烯-28-酸(2)、乌苏酸(3)、2α,3α,23-三羟基乌苏-12-烯-28-酸(4)、3β,24-二羟基乌苏-12-烯-28-酸(5)、3α-羟基乌苏-12-烯-28-酸(6)、豆甾烷-3,6-二酮(7)、7β-羟基谷甾醇(8)、豆甾醇(9)、β-胡萝卜苷(10)、棕榈酸(11).除化合物(3)和(10)外,其余均为首次从该植物中分离得到.     

尼泊尔水东哥的化学成分研究

从尼泊尔水东哥树皮的95%乙醇提取物中首次分离到12个化合物,应用波谱方法或与已知品对照的手段鉴定为auranamide(1)、aurantiamide benzoate(2)、齐墩果酸(3)、β-谷甾醇(4)、β-胡萝卜甙(5)、乌苏酸(6)、2α,3α-二羟基-12-烯-28-乌苏酸(7)、2α,3β,24-三羟基-12-烯-28-乌苏酸(8)、(2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol(9)、2α,3α,24-三羟基-12-烯-28-齐墩果酸(10)、2α,3β-二羟基-12-烯-28-乌苏酸(11)和2α,3α,24-三羟基-12-烯-28-乌苏酸(12)。     

红根草三萜类化学成分的研究

该研究利用大孔吸附树脂D101、MCI树脂、正相硅胶、ODS、Sephadex LH-20和反相HPLC等多种色谱分离方法,对红根草95%乙醇提取物的乙酸乙酯萃取部位进行了分离。结果表明:通过分离共得到了10个化合物,经波谱数据分析鉴定为3-表-白桦脂酸(1)、白桦脂醇(2)、齐墩果酸(3)、3β,6β,23-三羟基-12-烯-28-齐墩果酸(4)、高根二醇(5)、2α,3β,23-三羟基-12-烯-28-乌苏酸(6)、2α,3β,19α-三羟基-12-烯-28-乌苏酸(7)、2α,3α,24-三羟基-12-烯-28-乌苏酸(8)、2α,3α,24-三羟基-12,20(30)-二烯-28-乌苏酸(9)、山奈酚-3-O-葡萄糖苷(10)。其中,化合物1为首次从鼠尾草属植物中分离得到,化合物2、4、5、6、7、8、9、10为首次从该植物中分离得到。     

海莲内生真菌Pestalotiopsis clavispora代谢产物研究

从海莲内生真菌Pestalotiopsis clavispora发酵液乙酸乙酯萃取物中分离得到9个化合物。根据波谱数据,化合物1－9结构分别鉴定为：3β,22β,24-三羟基齐墩果-12-烯,乌苏酸,3-羟基-4-甲氧基苯乙烯,邻苯二甲酸二异丁酯,3,4-二羟基苯乙醇,对羟基苯乙醇,3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯,麦角甾-4,6,8(14),22-四烯-3-酮,胸苷。9个化合物均为首次从该内生真菌中分离得到。     

光果金樱子三萜类化合物的分离鉴定与抗SARS-CoV-2活性评价

为了解光果金樱子(Rosa laevigata var. leiocapus)的三萜类化学成分及其抗严重急性呼吸综合征冠状病毒2活性(severe acute respiratory syndrome coronavirus 2, SARS-CoV-2)，运用多种色谱分离技术从其95%乙醇提取物中分离得到15个三萜化合物。根据理化性质及波谱数据，分别鉴定为：laevigaterpeneA(1)、2α,23-二羟基齐墩果酸(2)、1β-羟基蔷薇酸(3)、3β-(p-hydroxytrans-cinnamoyloxy)olean-12-en-28-oic acid (4)、3β-反式对羟基肉桂酰氧基-2α-羟基齐墩果酸(5)、2α,3α-二羟基-12-烯-28-齐墩果酸(6)、坡模酸(7)、桦木酸甲酯(8)、2α,3α,19α,23-四羟基-12-烯-乌苏酸(9)、乙酰基-11α-甲氧基-β-乳香酸(10)、阿江榄仁尼酸(11)、2α,3α,19α-trihydroxy-28-norurs-12-ene (12)、蔷薇酸(13)、2α,19α-dihydroxy-3-oxo-12-urse...     

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。     

齐墩果酸氧化产物的成分研究

以齐墩果酸为原料,分别用高锰酸钾和SeO2/H2O2(30%)进行氧化。从产物中分离得到3个化合物,经1H NMR、13C NMR、2D-NMR、MS等波谱分析,分别鉴定为3,11-二羰基-12,17-二烯-28-去甲基齐墩果烷(1)、3β-羟基-11-烯-13,28-内酯-齐墩果烷(2)和3α,12β,13α-三羟基-28-羧基齐墩果烷(3),收率依次是4.5%、6.4%、2%,其中化合物1和3为新化合物。     

连钱草化学成分研究

从连钱草(Glechoma longituba)分离并鉴定了10个化合物,分别为β-谷甾醇(1)、齐敦果酸(2)、熊果酸(3)、2α,3α-二羟基乌苏-12-烯-28-酸(4)2、α,3β-二羟基乌苏-12-烯-28-酸(5)、胡萝卜苷(6),3,6-二甲氧基-6″,6″-二甲基苯并吡喃-(7,8,2″,3″)-黄酮(7)、芫花素(8)、芹菜素-7-O--βD-葡萄糖苷(9)、木犀草素-7-O-β-D-葡萄糖甙(10)。其中化合物2,4~8首次从该植物中分离得到。     

中华小苦荬萜类化学成分的研究(英文)

从中华小苦荬全草的乙酸乙酯提取物中分离得到8个萜类化合物,通过波谱方法及文献对照分别鉴定为β-香树脂素(1),3β-羟基-20(30)-蒲公英甾烯(2),熊果-12-烯-3β-醇(3),羽扇豆醇(4),10-羟基艾里莫芬-7(11)-烯-12,8α-内酯(5),乌苏-12,20(30)-二烯-3β,28-二醇(6),3β,8α-二羟基-6β-当归酰基艾里莫芬-7(11)-烯-12,8β-内酯(7)和乌苏酸(8),化合物1～8均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.