长缘厚朴中的新配糖体

从长缘厚朴（Magnolia rostrata W.W.Smith)干燥树皮的乙醇提取物中分离得到一个新的配糖体,1,1'－联苯－6',8',9'-三羟基－3－丙基－4－O－β－D吡喃葡萄糖苷（1）,以及6个已知的苯丙素类配糖体,3,4－二羟基－烯丙基－3－O－α－L－吡喃鼠李糖（1→6）β－D－吡喃葡萄糖苷（2）,3,4－二羟基－烯丙基苯－3－O－α－L－吡鼠李糖（1→2）β－D－吡喃葡萄糖苷（3）,sinapaldehyde(E)-O-β-D-glucopyranoside(4),syringaresinol-di-O-β-D-glucopynanoside(5),A阿克苷（E）（6）,IcarisideE5(7),经光谱和化学方法鉴定其结构。     

灯盏花中的糖苷

从灯盏花（Erigeron breviscapus (Vant.) Hand.-Mazz.) 全株的乙醇提取物的正丁醇部分分得10个化合物,通过波谱方法鉴定为erigeside I(1)、γ－吡喃酮－3－O－β－D－[6′－（4″－羟基－3″,5″－二甲氧基苯甲酰）-]-吡喃葡萄糖苷（erigeside D,2)、erigeside A(3)、erigeside B(4)、erigeside Ⅱ(5)、7-O-β-D-吡喃葡萄糖－6－甲氧基香豆素（6）、icariside B2(7)、blumenol C葡萄糖苷（8）、（＋）－丁香树酯醇O－β－D－吡喃葡萄糖苷（9）和野黄芩苷甲酯（10）。用X射线单晶衍射方法确定了化合物7的绝对构型。2是一个新化合物,7、8和9首次从该属植物分离得到,6首次从该种植物分离得到。     

杜仲皮中木脂素类化学成分及其对高糖诱导的肾小球系膜细胞保护作用研究

研究杜仲皮中的木脂素类化学成分,并评价其对高糖诱导的人肾小球系膜细胞的保护作用。将杜仲树皮粉碎后,纯化水提取,采用HPD-100大孔吸附树脂、硅胶、Sephadex LH-20、半制备高效液相色谱等方法进行分离,根据理化性质和波谱学方法鉴定化合物结构,从杜仲皮水提物中分离鉴定了6个木脂素类化合物,包括caruilignan D(1)、(-)-表松脂素(2)、(+)-松脂素4-O-β-D-吡喃葡萄糖苷(3)、(-)-松脂素4-O-β-D-吡喃葡萄糖苷(4)、(+)-中脂素4-O-β-D-吡喃葡萄糖苷(5)和(+)-中脂素4′-O-β-D-吡喃葡萄糖苷(6),化合物1为首次从杜仲中分离得到。在高糖诱导异常增殖的肾小球系膜细胞模型中,采用MTT法检测木脂素类化合物干预后的细胞活力。化合物5能剂量依赖性地抑制细胞增殖,对高糖诱导的肾小球系膜细胞具有保护活性。     

中药金樱子的化学成分

从中药金樱子（Rosa laevigata Michx.）的果实是分离到7个化合物,经理化性质和波谱分析分别确定为β－谷甾醇（1）、胡萝卜甙（2）、乌苏酸（3）、2α,3β,19α,23－四羟基乌苏－12－烯－28酸（4）,2α,3β,19α,23－四羟基乌苏－12－烯－28酸28－O-β-D-吡喃葡萄糖苷（5）,2α,3β,19α,23－三羟基乌苏－12－烯－28酸（6）和4',5,7－三羟黄酮醇－3－O－β-D-（6”－O－（E）－p－羟基苯丙烯酰）吡喃葡萄糖苷（7）,其中化合物4、5、7为首次从金樱子果实中分离得到。     

珍珠菜中黄酮及Megastigmane类化学成分研究北大核心CSCD

对珍珠菜Lysimachia clethroides的化学成分进行研究。应用硅胶、Sephadex LH-20和制备型HPLC等柱色谱技术进行分离纯化,并运用现代波谱技术（ESI-MS,^1H-NMR,^13C NMR）进行结构鉴定。从珍珠菜中分离得到12个化合物,分别鉴定为山柰酚（1）、槲皮素（2）、cinchonain Ib（3）、芹菜素-6-C-β-D-吡喃木糖基-8-C-α-L-吡喃阿拉伯糖苷（4）、芹菜素-6,8-二-C-α-L-吡喃阿拉伯糖苷（5）、芹菜素-6-C-α-L-吡喃阿拉伯糖基-8-C-β-D-吡喃木糖苷（6）、芹菜素-6,8-二-C-β-D-吡喃木糖苷（7）、芹菜素-6-C-β-L-吡喃阿拉伯糖基-8-C-β-D-吡喃葡萄糖苷（8）、芹菜素-6-C-α-L-吡喃阿拉伯糖基-8-C-β-D-吡喃葡萄糖苷（9）、芹菜素-6-C-β-D-吡喃葡萄糖基-8-C-α-L-吡喃阿拉伯糖苷（10）、blumenol A（11）、（3S,5R,6R,7E,9S）-大柱香波龙-7-烯-3,5,6,9-四醇-3-O-β-D-吡喃葡萄糖苷（12）。化合物3-8和11-12为首次从该属植物中分离得到。体外活性测试结果显示化合物1-12均没有明显的细胞毒活性（IC50〉10 μM）。     

荔枝核的五个苷类成分

通过溶剂分部和多种色谱分离,从荔枝(Litchi chinensis Sonn.)核中得到5个苷类成分。经光谱分析及与文献数据对照,分别鉴定为(-)-松脂素4-O-β- D-吡喃葡萄糖苷 (1)、苯乙基β- D-吡喃葡萄糖苷 (2)、乙基β- D-吡喃葡萄糖苷 (3)、乙基α- D-吡喃葡萄糖苷 (4)和胞苷 (5)。它们均为首次从荔枝核中分离得到。     

厚朴叶中具血管舒张作用的化学成分研究

实验采用离体血管环灌流模型,观察厚朴叶正丁醇萃取部位对去甲肾上腺素预收缩的内皮完整和去除内皮的家兔离体血管环张力的影响。结果显示:厚朴叶正丁醇萃取部位对内皮完整和去除内皮的血管环在一定剂量内呈现浓度依赖性舒张作用,该作用可能与该部位大量成分———槲皮苷和芦丁有关。从该部位分离得到7个化合物,分别为槲皮苷(1),芦丁(2),紫丁香苷(3),丁香脂素-4,4’-双-O-β-D-葡萄糖苷(4),芥子醛-4-O-β-D-吡喃葡萄糖苷(5),松脂素-4-O-β-D-吡喃葡萄糖苷(6),丁香脂素-4-O-β-D-吡喃葡萄糖苷(7)。其中化合物4和6首次从该种植物中分离得到。     

鞑靼滨藜地上部分化学成分的研究

从鞑靼滨藜（Atriplex tatarica）首次分离得到6个化合物,通过理化及波谱分析,它们分别确定为苜素（tricin,1）,苜蓿素-7-O-β-D-吡喃葡萄糖苷（tricin 7-O-β-D-glucopyranoside,2）,异鼠李素（isorhanmetin,3）,异鼠李素．3-芸香糖甙（Isorhamnetin-3-rutinoside,4）,豆甾醇（stigmasteml,5）,β-谷甾醇（β-sitosterol,6）。     

缘毛紫菀化学成分研究

目的:对藏紫菀来源之一——缘毛紫菀(Aster souliei Franch.)的头状花序的化学成分进行研究。方法:采用硅胶柱层析、凝胶柱层析以及制备型液相等方法分离化学物,并采用光谱学方法进行结构鉴定。结果:从缘毛紫菀中分离鉴定了9个化合物,分别为黄酮类的槲皮素(1)、芹菜素(2)、山柰酚(3)、柚皮素(4)、芹菜素-7-O-β-D-吡喃葡萄糖苷(5)、芹菜素-7-O-β-D-吡喃葡萄糖醛酸苷(6);植物甾醇类的β-谷甾醇(7)、β-胡萝卜苷(8)、α-菠甾醇-3-O-β-D-吡喃葡萄糖苷(9)。结论:化合物4、9为该植物中首次分离得到。     

弯蕊开口箭中的新甾体配糖体

从百合科植物弯蕊开口箭（Tupistra Hook,f．）的根茎中分离得到4个新的甾体配糖体,分别命名为弯蕊苷（wattoside)B-E(1-4),其中,3个多羟基呋甾型配糖体,另1个为强心苷,经化学降解和光谱分析,其化学结构分别鉴定为：22－0－甲基－25（R,S）,－呋甾烷－1β,3β,4β5β,22ξ,26β－六醇－26－O－β－D－葡萄吡喃糖苷（1）：22－O－甲基－26－O－β－D-葡萄吡喃糖基－25（S）－呋甾烷－5－烯－β,3β,22ξ,26β－甲醇－3－0－[O-β-D-葡萄吡喃糖基（1－4）]－β－D-半乳吡喃糖苷（2）;22－0－甲基－25（S)-呋甾烷－1β,2β,3β,4β,5β,22,26β－七醇－26－O-β－D－葡萄吡喃糖苷（3）和夹竹桃苷元－3－O－[O-β-D-葡萄吡喃糖基（1－2）]－α－L－鼠李吡喃糖苷,弯蕊苷E为开口箭属植物中首次分离到的强心苷。     

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.