霍山三种石斛与其栽培土壤中微量元素分布关系研究

本文应用灰色系统理论,对安徽霍山三种石斛与其栽培土壤中15种微量元素分布状况进行了关联分析．结果发现.其关联序为γ_根＞γ_叶＞γ_茎;γ_(-年茎)≈γ_(二年茎)≈γ_(三年茎);γ_(霍斛)＞γ_(铁斛)＞γ_(铜斛).可见霍山石斛与其栽培土壤间的微量元素相关性比其它石斛强,因而可通过增施微肥的办法来提高霍山石解中某些人体必需微量元素的含量．     

霍山石斛产业化发展的问题与对策

介绍了霍山石斛的概况,阐述了霍山石斛产业化发展的重要性和可行性。在分析了霍山石斛资源状况的基础上,着重剖析了霍山石斛产业化发展面临的主要问题,提出了相应的对策措施,旨在为霍山石斛的产业化开发与持续利用提供依据。     

群体表型性状研究揭示环境与遗传因素对霍山石斛表型及物种分类的影响

石斛属(Dendrobium)种类繁多, 属内物种具有丰富的表型多样性。霍山石斛(D. huoshanense)为我国特有物种, 其与河南石斛(D. henanense)和细茎石斛(D. moniliforme)以及铁皮石斛(D. catenatum)等近缘种表型相似, 在分类处理中存在争议。这种争议很大程度上与植物普遍存在的表型可塑性和代际共存有关。为探究环境和代际间遗传因素对霍山石斛表型性状的影响以及霍山石斛与近缘种的物种边界问题, 本研究观测了安徽省霍山县霍山石斛(野生、林间和温室F₁代、林间和温室F₂代)、野生河南石斛、细茎石斛和铁皮石斛, 共计16个群体2,279株植株的假鳞茎茎长等12个表型性状; 在种内层面, 首次借鉴生态学同质园实验和遗传学代际间性状比较的方法, 对霍山石斛群体表型性状进行差异显著性检验和95%置信区间比较以及主成分和变异系数等统计学分析。在种间层面, 对霍山石斛与河南石斛和铁皮石斛等近缘种群体表型性状进行比较和分析。结果表明, 环境因素对霍山石斛假鳞茎茎长和假鳞茎直径等具有显著的影响, 代际间遗传因素对霍山石斛假鳞茎直径具有显著的影响。霍山石斛与铁皮石斛和细茎石斛等近缘种群体在假鳞茎茎长、假鳞茎直径、花瓣长和花瓣宽等表型性状方面均存在显著性差异和间隔, 但与河南石斛仅在假鳞茎表型性状方面有显著性差异。我们的研究明确了环境和代际间遗传因素对霍山石斛表型性状的影响程度, 为霍山石斛与近缘种等争议物种的分类和鉴定提供了表型证据。     

道地药材霍山石斛及其相似种的分子鉴定

为检测霍山石斛与霍山产铜皮石斛、霍山产铁皮石斛及其它产地的几种药用石斛的差异,对霍山石斛及其相似种进行ISSR分子标记比较研究。结果表明,尽管霍山石斛及其相似种的外部形态差异较小,但在ISSR分子标记指纹图谱上却存在着显著而稳定的差异。因此,根据ISSR分子标记指纹图谱所显示的多态性位点差异,能准确鉴别霍山石斛及其相似种植物及药材。此方法简单、稳定性高、可重复性好,在霍山石斛的分子鉴定研究中有较大的应用价值。     

组培霍山石斛、野生霍山石斛及河南石斛多糖及乙醇溶出物动态积累规律研究

为了揭示不同种源的霍山石斛及其近缘种河南石斛多糖和醇溶性浸出物含量的动态变化规律,为霍山石斛和河南石斛规范化种植及品种鉴定提供依据,采用蒽酮-浓硫酸比色法和醇溶性浸出物热浸法对1~4年株龄的野生霍山石斛、组培霍山石斛和河南石斛的多糖和浸出物含量进行测定。结果表明,不同株龄的组培霍山石斛、野生霍山石斛和河南石斛的多糖、浸出物含量均存在极显著差异。以多糖含量为标准,三者均以生长2年采收为宜,以醇溶物为标准,以栽培三年采收最好。以多糖和醇溶出物总量计,组培霍山石斛以2年采收为宜,野生霍山石斛及河南石斛以3年株龄品质最佳。     

霍山石斛多糖吸湿保湿性能及皮肤刺激性研究北大核心CSCD

为探讨霍山石斛多糖吸湿保湿性能及皮肤刺激性,应用干燥器控制湿度对霍山石斛多糖进行体外吸湿(43%、81%)和保湿性能研究,应用皮肤水分测定仪对霍山石斛多糖进行人体皮肤保湿性能研究,应用家兔正常皮肤和破损皮肤进行霍山石斛多糖皮肤刺激性研究。结果显示:霍山石斛多糖体外吸湿率随环境湿度的升高而升高,相对湿度43%、81%的吸湿率强弱为丙三醇>霍山石斛多糖>壳聚糖>海藻酸钠;体外的保湿强弱为壳聚糖>霍山石斛多糖>海藻酸钠>丙三醇,霍山石斛多糖在涂抹后6、8、12 h的人体皮肤保湿率显著高于丙三醇保湿率,12 h显著高于海藻酸钠保湿率,与壳聚糖保湿率无显著性差异;家兔正常皮肤及破损皮肤刺激值小于0. 5。表明霍山石斛多糖具有一定的吸湿保湿性能,且无皮肤刺激性,具有开发为天然保湿剂的潜能。     

霍山石斛多糖吸湿保湿性能及皮肤刺激性研究

为探讨霍山石斛多糖吸湿保湿性能及皮肤刺激性,应用干燥器控制湿度对霍山石斛多糖进行体外吸湿(43%、81%)和保湿性能研究,应用皮肤水分测定仪对霍山石斛多糖进行人体皮肤保湿性能研究,应用家兔正常皮肤和破损皮肤进行霍山石斛多糖皮肤刺激性研究。结果显示:霍山石斛多糖体外吸湿率随环境湿度的升高而升高,相对湿度43%、81%的吸湿率强弱为丙三醇霍山石斛多糖壳聚糖海藻酸钠;体外的保湿强弱为壳聚糖霍山石斛多糖海藻酸钠丙三醇,霍山石斛多糖在涂抹后6、8、12 h的人体皮肤保湿率显著高于丙三醇保湿率,12 h显著高于海藻酸钠保湿率,与壳聚糖保湿率无显著性差异;家兔正常皮肤及破损皮肤刺激值小于0. 5。表明霍山石斛多糖具有一定的吸湿保湿性能,且无皮肤刺激性,具有开发为天然保湿剂的潜能。     

霍山石斛多糖的分离鉴定及药理活性研究进展

霍山石斛是我国传统医药中的一种名贵中药材,拥有中华九大仙草之首的美誉,明确收录于《本草纲目拾遗》,其干燥茎和鲜品均可入药,具有悠久的药用历史和良好的药用价值。近年来,国内外学者对霍山石斛多糖的结构分析和药理活性等方面进行了大量深入研究,为霍山石斛资源的开发利用提供了理论依据,通过相关文献查阅,本文主要就霍山石斛多糖的分离鉴定及药理活性相关研究进展进行概述,为霍山石斛多糖的进一步研究奠定基础。     

不同产地铁皮石斛主要成分及甲醇提取物HPLC指纹图谱研究

本文采用紫外分光光度法、高效液相色谱法(HPLC)测定铁皮石斛中总黄酮、多糖、柚皮素、石斛酚的含量,同时运用HPLC法建立霍山铁皮石斛及其他产地铁皮石斛甲醇提取物HPLC指纹图谱并聚类分析。实验结果显示不同产地铁皮石斛的主要化学成分含量存在差异,5批霍山铁皮石斛的总黄酮、柚皮素、石斛酚含量较高,多糖含量较低。建立了霍山铁皮石斛的共有指纹图谱模式,5批霍山铁皮石斛具有极高的相似度,在92.6%~94.8%之间,浙江临安、浙江乐清、江苏盐城、云南昆明所产的铁皮石斛相似度在17.5%~41.5%之间。5批来自安徽霍山的铁皮石斛共有峰总面积较高,为9 827.40~14 102.28。其他产地铁皮石斛的共有峰面积在730.27~4 206.20之间,明显低于霍山铁皮石斛。聚类分析结果可分为两大类,安徽霍山为一类,其他产地为一类。霍山铁皮石斛与其他产地铁皮石斛存在一定差异,且小分子成分含量较高。上述结果为进一步研究霍山铁皮石斛化学成分提供参考,为铁皮石斛品质鉴别、质量控制及资源的综合利用提供实验依据。     

霍山石斛和铁皮石斛干花成分含量和抗氧化性的比较

探究同一生长条件下2种石斛干花所含主要成分的种类和含量,并评价成分的抗氧化作用。用国标法检测两种石斛干花的主要成分,用清除DPPH和铁氰化钾还原法研究成分的抗氧化性。霍山石斛干花粗蛋白、维生素C、单宁、总酸、多酚、黄酮含量与铁皮石斛干花的差异显著(P0.05),粗多糖、粗脂肪含量与铁皮石斛干花差异不显著(P0.05),两种石斛干花均含有17种常见氨基酸,其中霍山石斛干花必需氨基酸含量显著高于铁皮石斛干花,两种石斛干花提取液都具有一定的抗氧化性,以霍山石斛干花提取液的抗氧化性表现较强。霍山石斛干花有很高的营养价值和抗氧化性,更具备新食品研究开发和应用价值。     

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).     

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.