丹参四个栽培类型的脂溶性成分的聚类分析

为给丹参优质新品种选育研究提供一定的理论依据,本文采用HPLC法测定江苏栽培的四个丹参类型的丹参酮IIA、隐丹参酮的含量,采用紫外分光光度法测定其总丹参酮的含量,以DPS软件对其脂溶性成分的HPLC的8个峰的比例、隐丹参酮与丹参酮IIA的比值、丹参酮IIA、隐丹参酮和总丹参酮的含量进行聚类分析。结果表明四个类型丹参的脂溶性成分类别基本一致,其中小叶型丹参的隐丹参酮与丹参酮IIA的比值、隐丹参酮的含量与其它三个类型相差较大,聚类结果显示小叶型丹参独自成为一个类群,说明小叶型丹参为一个较为特殊的类型,也是一个优质的丹参材料。     

脱落酸不同处理时间对丹参毛状根有效成分积累的影响

采用HPLC测定脱落酸(abscisic acid,ABA)处理1、3、6、9 d后丹参毛状根中丹参酮I、隐丹参酮、二氢丹参酮I、丹参酮IIA含量的方法,研究不同ABA处理时间对丹参酮类成分积累的影响。结果表明:①随着ABA处理时间的增加,丹参毛状根生长受到抑制逐渐减弱,并在处理6 d左右变的不显著;②毛状根中四种丹参酮的产量和含量均在ABA处理6 d左右趋于稳定。其中丹参酮I、隐丹参酮、二氢丹参酮I和丹参酮II的产量分别提高为空白对照组的4.65、7.80、18.33和2.11倍;③三种丹参酮类合成抑制剂均对丹参毛状根的生长、丹参酮类的合成有抑制作用。     

丹参酮Ⅰ通过诱导凋亡抑制HepG2细胞生长

目的:研究丹参酮Ⅰ对肝癌细胞HepG2生长的影响。方法:MTT法检测丹参酮Ⅰ对HepG2细胞增殖的影响,Western印迹检测经丹参酮Ⅰ处理的HepG2细胞中凋亡标志物c-Parp和周期蛋白D1的表达变化,流式细胞术检测细胞的凋亡及周期分布。结果:MTT分析发现丹参酮Ⅰ可抑制HepG2细胞的生长;经丹参酮Ⅰ处理的HepG2细胞中凋亡标志物c-Parp表达升高,周期蛋白D1表达无明显变化;流式细胞术分析结果进一步证明丹参酮Ⅰ可诱导HepG2细胞发生凋亡,对细胞周期分布无明显影响。结论:丹参酮Ⅰ通过诱导细胞凋亡而抑制HepG2细胞的生长,对细胞周期无明显阻滞,为进一步研究丹参酮Ⅰ的抗肿瘤作用分子机制提供了线索。     

mTORC2/Akt的反馈激活可拮抗隐丹参酮对HepG2细胞的抑制作用

目的:研究隐丹参酮对Akt活性的影响及其在抑制HepG2细胞生长中的作用。方法:Western印迹检测隐丹参酮对Akt磷酸化的影响;CCK-8法检测隐丹参酮与MK2206或PP242联合用药对HepG2的生长抑制作用。结果:Western印迹证明隐丹参酮处理能够增强HepG2细胞Akt的磷酸化,同时发现隐丹参酮对Akt的增强作用依赖于mTORC2的活性;通过MK2206或PP242抑制Akt的反馈激活,能够明显促进隐丹参酮对HepG2细胞的生长抑制作用。结论:通过抑制Akt的反馈激活能够增强隐丹参酮的抗肿瘤作用,为隐丹参酮肿瘤治疗的临床应用联合用药提供了理论基础。     

回流提取过程中丹参酮的热降解行为研究

用甲醇作提取溶剂,在回流条件下考察了从丹参药材中提取丹参酮类有效成分的过程中,隐丹参酮、丹参酮I及丹参酮IIA等三种丹参酮的热降解行为。结果表明,回流提取过程中所考察的三种丹参酮均发生严重的热降解,降解速率:丹参酮IIA>丹参酮I>隐丹参酮,其热降解均具有零级反应动力学特征;同时,回流提取过程中丹参酮的热降解是在丹参酮共萃物存在下发生的。     

基于组学的丹参酮生物合成途径新基因CYP71D375克隆和功能研究

丹参酮能有效治疗心脑血管疾病,其生物合成途径解析是国内外研究热点,其中CYP450氧化酶超家族的关键修饰作用最受关注.基于药用模式植物丹参的基因组及转录组数据分析,本研究克隆到一个新的CYP450氧化酶编码基因,命名为SmCYP71D375,全长1515 bp,编码504个氨基酸,差异表达分析显示,该基因在丹参的根及根周皮部位显著高表达,与丹参酮合成和积累的部位一致,推测其催化丹参酮的生物合成.进一步构建RNAi转基因毛状根体系,通过化学检测及代谢组学分析发现抑制SmCYP71D375的基因表达导致羟基丹参新酮、丹参新酮、隐丹参酮、丹参酮ⅡA等含量显著降低,证实SmCYP71D375在丹参体内催化丹参酮的生物合成.本研究为解析丹参酮的生源途径提供新思路,对植物高氧化次生代谢产物合成途径研究具有重要示范意义.     

过表达丹参GGPPS研究丹参酮类的生物合成途径

丹参酮是药用植物丹参(Salvia miltiorrhiza)中具有较强生物活性的脂溶性二萜醌类化合物,是目前国际上广泛认可的有效治疗心脑血管疾病的天然药物之一.本研究通过分析过表达萜类生物合成途径中的牻牛儿基牻牛儿基焦磷酸合酶(GGPPS)的转基因丹参,发现丹参酮类化合物与叶绿素具有共同的上游生物合成途径,而下游途径因组织的特异化而不同,从而生成不同的代谢产物.通过对丹参毛状根外施两个萜类生物合成途径的抑制剂Lovastatin和Fosmidomycin,在处理6周丹参酮积累达到稳定时测定丹参酮的含量,探明了丹参酮类的生物合成主要是通过质体中的MEP途径来完成,而非胞质中的MVA途径.本研究为丹参酮类的代谢生物学及合成生物学研究提供了证据和基础.     

丹参酮生物合成途径及其相关酶的研究进展

丹参酮是丹参中具有多种药理活性的二萜醌类化合物，对预防和治疗心脑血管系统疾病有显著效果。因其具有重要的经济和药用价值，丹参酮的生物合成研究受到人们的广泛关注。随着丹参基因组和转录组数据的不断积累和完善，以及丹参遗传转化体系的建立和基因编辑技术的应用，丹参酮的生物合成途径解析及相关酶基因研究取得了新进展。现系统阐述丹参酮的生物合成途径与研究进展，同时对合成途径相关酶基因的研究现状进行概述，并展望未来的研究方向。     

丹参酮Ⅱ-A在RAW264.7细胞系中的抗炎症作用机制

目的:丹参酮Ⅱ-A是丹参的一种重要成分。研究丹参酮Ⅱ-A的抗炎症机制。方法:以小鼠腹腔巨噬细胞系RAW264.7作为药物刺激靶细胞,使用不同浓度的分析纯丹参酮Ⅱ-A对RAW264.7细胞系进行刺激,在细胞被刺激24、48h后,使用MTT比色法和半定量RT-PCR法对刺激后的细胞进行检测。结果:通过MTT比色法检测,发现丹参酮Ⅱ-A抑制炎症细胞的增殖,初步计算出丹参酮Ⅱ-A的半抑制浓度(IC50)为43.2μmol/L;在半定量RT-PCR实验中发现,在发生炎症后,丹参酮Ⅱ-A通过抑制磷脂酶A2来减轻炎症。结论:在炎症发生后,丹参酮Ⅱ-A通过抑制磷脂酶A2来达到其抗炎症的作用。     

丹参酮ⅡA结构修饰及其对HeLa细胞的抑制作用研究

本研究运用Mannich反应,得到了丹参酮ⅡA的16位被酯化氨基酸取代的5个衍生物,结构均经EI-MS、1H及13C NMR确证。经MTT法测定丹参酮ⅡA及其衍生物对HeLa细胞增殖的抑制作用,并计算出IC50。结果表明,5个衍生物的生物活性较丹参酮ⅡA均有所增强;即丹参酮ⅡA在16位进行结构修饰可以增强其对肿瘤细胞抑制活性。     

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.     

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     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

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.     

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).