不同产地怀牛膝β-蜕皮甾酮含量测定及指纹图谱研究

建立怀牛膝中β-蜕皮甾酮的HPLC含量测定和指纹图谱方法,比较不同产地牛膝的质量差异。采用Waters SunFire C18色谱柱(250 mm×4.6 mm,5μm),以甲醇和水为流动相,进行梯度洗脱,流速1.0 mL/min,柱温30℃,检测波长250 nm。β-蜕皮甾酮在0.26μg～2.60μg线性关系良好(r=0.9994),平均回收率为100.29%(RSD=2.42%,n=6);建立了怀牛膝药材的HPLC指纹图谱,标定了怀牛膝药材中7个共有峰,并对21个不同产地的牛膝药材进行了测定。该方法简便、准确、重现性好,可为怀牛膝质量控制和道地性研究提供依据。     

国产巴西人参的生药学

为了进一步开发国内引种栽培的巴西人参药材,通过对巴西人参的原植物形态、药材性状、粉末显微鉴别及薄层层析等进行分析研究,发现该药材的原植物形态特征基本稳定、根横切面结构除三生维管束构造异常外其余特征稳定,粉末鉴别草酸钙砂晶特征明显,药材与对照药材及β-蜕皮甾酮对照品在相应位置均有相同颜色斑点显现.实验结果稳定,可作为巴西人参生药学鉴别的重要依据.     

安徽东至中药材粗榧高效液相指纹图谱和化学成分分析

建立安徽东至粗榧药材高效液相指纹图谱,比较不同产地、不同干燥方法、不同药用部位粗榧药材的质量.以Kromasil C18为分析柱,用甲醇-乙腈(1:1)和0.1%醋酸水溶液梯度洗脱进行色谱分离,利用有效部位HPLC图谱辅助对共有峰进行指认,标示出13个共有峰,使用计算机辅助相似度评价软件进行数据处理.通过对不同产地、不同干燥方法、不同药用部位粗榧药材指纹图谱的分析,发现不同来源粗榧药材化学组成相似,其相对比例具有差异.通过HPLC-UV-MS/MS联用分析以及分离纯化鉴定两个主要化学成分的结构,它们分别为芹菜素-5-O-α-L-吡喃鼠李糖基-(1→4)-β-D-吡喃葡萄糖苷,芹菜素-5-O-α-L-吡喃鼠李糖基-(1→4)-6"-O-乙酰基-β-D-吡喃葡萄糖苷,干燥过程可能使它们发生转化.指纹图谱用于粗榧药材的质量评价切实可行,方法重现性好.     

国产巴西人参的生药学

为了进一步开发国内引种栽培的巴西人参药材,通过对巴西人参的原植物形态、药材性状、粉末显微鉴别及薄层层析等进行分析研究,发现该药材的原植物形态特征基本稳定、根横切面结构除三生维管束构造异常外其余特征稳定,粉末鉴别草酸钙砂晶特征明显,药材与对照药材及β-蜕皮甾酮对照品在相应位置均有相同颜色斑点显现。实验结果稳定,可作为巴西人参生药学鉴别的重要依据。     

不同产地野生与栽培伊贝母药材水溶性成分指纹图谱研究

目的:建立伊贝母药材水溶性成分高效液相色谱指纹图谱,为科学评价和有效控制其质量提供可靠的方法。方法:采用HPLC-DAD方法,以Kromasil C18色谱柱(4.6 mm×150 mm,5μm),流动相为甲醇和水,梯度洗脱,流速0.5 mL·min-1,柱温25℃,检测波长:260 nm。采用药典委员会颁布的中药色谱指纹图谱相似度评价系统2004 A版软件,对29批野生与栽培伊贝母药材进行指纹图谱分析。结果:29批伊贝母药材中有14个共有特征峰,建立了HPLC指纹图谱共有模式。各批次伊贝母药材相似度都在0.714以上,29批野生与栽培伊贝母药材可通过系统聚类分成5类,不同产地野生与栽培药材组成质量相似性较好,并定量测定了样品中的β-胸苷和腺苷。结论:所建立的HPLC指纹图谱及定量分析均具有良好的精密度、重复性、稳定性,可用于伊贝母药材的质量综合评价。     

不同采收期栽培宽叶羌活挥发性成分的研究

采用水蒸气蒸馏法提取不同采收时间(5、6、7、8和9月)栽培宽叶羌活药材中的挥发油,测定其含量;通过GC-MS对挥发油成分进行了分析鉴定,并采用面积归一化法计算各组分的相对含量。实验结果表明,不同采收时间,栽培宽叶羌活挥发油含量存在差异,以8月份采收的药材挥发油含量最高;挥发油经GC-MS分析,共鉴定出39个化合物,有31种共有成分;对共有组分进行主成分分析显示,香桧烯、α-蒎烯、莰烯、β-蒎烯、γ-萜品烯、乙酸龙脑酯、α-红没药醇等15种成分可作为挥发油季节变化的特征组分。不同季节采集的羌活生药材,其挥发油含量和成分具有一定的差别,在一定程度上反映了其药用价值的微妙差异,可为羌活药材药理药用价值的进一步开发利用提供一定的参考。     

HPLC特征图谱结合化学计量学评价独一味药材及其与独一味胶囊的一致性

采用HPLC方法建立独一味药材及独一味胶囊的特征指纹图谱,运用相似度评价药材质量;并结合化学计量学对独一味药材进行分类,以相对保留时间对独一味药材和独一味胶囊进行成分一致性评价。结果显示,独一味药材含共有峰23个,独一味胶囊含共有峰24个;10批独一味药材的相似度均大于0.85,可见药材来源较为单一;同时结合化学计量学中聚类分析和主成分分析对10批药材进行分类,可将其分为4类,且分类结果一致,可见以该法评价独一味药材可行;并对以同一HPLC特征图谱方法建立的独一味药材及独一味胶囊特征图谱进行比较,可知独一味胶囊很好的保留了独一味药材的诸多药效成分。     

孢粉药材及花类药材的孢粉形态(续)

 利用光学显微镜和扫描电子显微镜对10种孢粉药材及花类药材进行了孢子或花粉的显微和亚显微研究,为孢粉药材及花粉药材的鉴别提供了新的方法和科学依据。     

基于化学计量学结合HPLC指纹图谱评价桔梗药材质量

建立了桔梗药材HPLC指纹图谱检测方法,并基于化学计量学对不同产地桔梗药材进行了分析,为科学评价桔梗药材质量提供参考。收集11个省份的22批次桔梗药材,建立HPLC-ELSD指纹图谱,确定了9个共有峰,并对其中4个共有峰进行了明确的化学成分指认;应用化学计量学的聚类分析(cluster analysis,CA)、主成分分析(principal component analysis,PCA)和偏最小二乘-判别分析(partial least squares discriminant analysis,PLS-DA)多种分析方法对不同批次桔梗药材的指纹图谱进行评价。结合产地气候特征发现,温带季风气候更适于桔梗药材生长,所含药效化学成分丰富,质量更佳。本研究所建立的桔梗药材指纹图谱方法快速准确、灵敏度高、重复性好,结合化学计量学分析,可以对不同产地的桔梗药材质量进行评价,可为该桔梗药材的质量控制提供科学依据。     

蒙药材瑞香狼毒的化学成分研究

采用溶剂提取及柱色谱等方法,首次对瑞香狼毒Stellera chamaejasme L.的正丁醇萃取部位进行系统研究,分离得到6个苯丙素类化合物,并运用UV、1H NMR、13C NMR等现代波谱技术依次鉴定为伞形花内酯7-O-β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖苷(1),芥子醇1,3’-双-O-β-D-吡喃葡萄糖苷(2),紫丁香苷(3),(+)-落叶松树脂醇4,4’-O-β-D-吡喃葡萄糖苷(4),(+)-松树脂醇4,4’-O-双-β-D-吡喃葡萄糖苷(5)和(+)-丁香树脂醇-双-O-β-D-吡喃葡萄糖苷(6)。其中,化合物4、6为首次从该药材中分离得到。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

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.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).