中药前胡核磁共振氢谱法鉴定

使用＾１Ｈ－ＮＭＲ法对１９种前胡乙醚提取物进行了测试和解析,其中９种前胡的化学成分未见报道。根据主要化学成分香豆素的类型,将含角型二氢吡喃香豆素的１０种前胡归入白花前胡类;含线型二氢吡喃香豆素或线型二氢呋喃香豆素的８种前胡归秋紫花前胡类。研究结果表明,＾１Ｈ－ＮＭＲ法是鉴别中药前胡的快速、简便而可靠的检测方法。     

小前胡中香豆素类成分研究

本文对韩国植物新种小前胡(Angelica czernaeviaKita forma dentate Yook)的根部进行了化学成分研究,从中得到了7个香豆素类化合物,利用波谱方法分别鉴定为异欧前胡素(1),川白芷内酯(2),紫花前胡素(3),7-羟基香豆素(4),紫花前胡醇(5),紫花前胡苷元(6)和紫花前胡苷(7);同时采用高效液相色谱法对该植物的根、茎、叶和果实进行了主成分川白芷内酯(2)和紫花前胡素(3)定量分析。     

马山前胡的香豆素

从马山前胡(Peucedanum mashanense Shan et Sheh)中分离得到4个化合物,鉴定为香豆素化合物白花前胡丙素[( )pareruptorin A],白花前胡丁素[( )anomalin],虎耳草素(pimpinellin)和β-谷甾醇(β-sitosterol)。     

俯卧前胡的化学成分

从伞形科植物俯卧前胡(Peucedanum decumbens Maxiam)的根中分离鉴定了13个成分,其中化合物(1)是一个新的二氢呋喃香豆素,经各项光谱测定,确定其结构为:顺式-2′-(1″-甲基,1″-千里光酰氧基-乙基)-3′-羟基-线型二氢呋喃香豆素,命名为俯卧前胡素(decumbensol)。     

细裂前胡的香豆素成分

细裂前胡Peucedanum macilentum Franch。(伞形科)是云南西部应用的前胡地方品种,从其根的乙醇提取物中经硅胶柱层析得到6个化合物,分别鉴定为香豆素类化合物:伞形花内酯(umbelliferone)(1),佛手柑内酯(bergapten)(2),laserpitin(3),异白花前胡丁素(anomalin)(4);其它化合物:阿魏酸(ferulic acid)(5),β-谷甾醇(β-sitosterol)。     

水飞蓟油—一种很有开发利用价值的植物油

水飞蓟[Silybum marianum(L)Gaertn.],又名水飞雉、乳蓟,为菊科[Compositae]水飞蓟属植物,原产于南欧和北非。水飞蓟属共两种,另一种为象牙蓟[Silybum eburneum Coss. et Dur.]。常见的水飞蓟品种有紫花水飞蓟与白花水飞蓟[Silybum inarianum Var. albiflorum];白花水飞蓟系水飞蓟(紫花)的变种。在国外水飞蓟自古代就作为药用植物,应用较广泛的是德国民间,主要用于治疗肝胆疾     

遮阳对白花前胡叶片光合特性的影响

为规范白花前胡(Peucedanum praerupterum)种植和提高产量,对不同光强下白花前胡的光合特性进行了研究。结果表明,与遮阳40%和60%相比,对照(CK)和遮阳20%的白花前胡叶片具有更高的最大电子传递速率[分别为247.129和266.866μmol/(m~2·s)]和最大净光合速率[分别为25.621和28.167μmol/(m~2·s)],且最大净光合速率对应的饱和光强[分别为2 130.419和1 927.804μmol/(m~2·s)]也显著高于遮阳40%和60%处理。不同遮阳处理的白花前胡叶片的光能利用效率和水分利用效率有差异,但光化学猝灭系数和非光化学猝灭系数则无显著差异。这说明白花前胡为典型的阳生植物,光适应性较强,建议选择光强充足的开阔田地栽培白花前胡。     

泰山前胡化学成分的研究

泰山前胡(Peucedanum wawrii(Wolff)su.)为多年生草本,有镇咳,祛痰的功效有较多蕴藏量,但尚未加以利用现报道泰山前胡香豆素的研究结果。结晶 A,熔点138—140℃,分子式为 C_(24)H_(28)O_7,红外光谱提示有酯基、芳环、芳醚。质谱 m/z:M~ 428,核磁共振谱示有凯林(khellactone)母核,连结异戊草酸及当归酸。此结晶不溶于水,能溶于无水乙醇及氯仿等溶剂。经鉴定结晶 A 为白花前胡 E 素(3′-angeloyl-4′-isovaleryl-cis-khellactone)。     

中国伞形科前胡属果实表面微形态特征及分类学意义

采用扫描电镜方法对中国伞形科(Apiaceae)前胡属(Peucedanum L.) 22种2变种的果实表面微形态特征进行了观察和描述.结果显示:供试种类在果实棱槽细胞平滑度和细胞轮廓可见度、蜡质纹饰类型、细胞表面突起的有无及类型、表皮毛的有无及类型及其纹饰类型、表皮分泌物的有无及类型等方面有明显差异,具有丰富的种间多样性.根据这些特征可将供试种类分为4种类型.类型Ⅰ:棱槽细胞粗糙多毛—细胞轮廓不可见—簇状蜡质纹饰发达,包含滨海前胡(P.japonicum Thunb.)、天竺山前胡(P.ampliatum K.T.Fu)、华北前胡(P.harrysmithii Fedde ex Wolff)及其2变种、长前胡(P.turgeniifolium Wolff)、华山前胡(P.ledebourielloides K.T.Fu)和泰山前胡[P.wawrae (Wolff) Su ex Sheh];类型Ⅱ:棱槽细胞平滑无毛—细胞轮廓不可见或凹陷—条形蜡质纹饰发达或明显,包含芷叶前胡(P.angelicoides Wolff ex Kretschm.)、竹节前胡(P.dielsianum Fedde ex Wolff)、南川前胡[P.dissolutum (Diels)Wolff]、红前胡(P.rubricaule Shan et Sheh)、细裂前胡(P.macilentum Franch.)、前胡(P.praeruptorum Dunn)、华中前胡(P.medicum Dunn)、台湾前胡(P.formosanunt Hayata)、南岭前胡(P.longshengense Shum et Sheh)、会泽前胡(P.acaule Shah et Sheh)和马山前胡(P.mashanense Shan et Sheh);类型Ⅲ:棱槽细胞有稀疏毛—细胞轮廓[陷可见或不明显—蜡质纹饰几无,包含北京前胡(P.caespitosum Wolff)、草原前胡(P.stepposum Huang)、毛前胡(P.pubescens Hand.-Mazz.)和刺尖前胡(P.elegans Komarov);类型Ⅳ:棱槽细胞不平无毛—细胞轮廓呈近圆形凸起—蜡质纹饰为微波状长条形,仅包含石防风[P.terebinthaceum (Fisch.ex Trevir.)Fisch.ex Turcz.]1种.结合外部形态特征以及地理分布对各类型种类的分类关系进行了讨论,并对会泽前胡、马山前胡和石防风的特殊分类地位进行了分析,明确了果实表面微形态特征在前胡属中的分类学意义.     

前胡属（Peucedanum L.）血清分类学研究

利用琼脂板双扩散沉淀反应对我国前胡属（Peucedanum L.)13种2变种的叶片蛋白质进行了血清学分析,根据血清相似性将所分析的种类分成5个类群,其中石防风（p.terebinthaceum(Fisch)Fisch.ex Turcz.]刺尖前胡（p.elegans Komarov)和白花前胡（p.praeruptorum Dunn)各自为一类群,其余种类分别以华北前胡（p.harry-smithii Fedde ex Wolff)和华山前胡（p.ledebourielloides K.T.Fu)为代表分成二个类群,结合形态,地理等资料,分别讨论了各血清学类群的种间关系和分类学问题。     

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).