不同栽培年限黄花倒水莲产量与品质分析

为确定黄花倒水莲的适宜采收期，该研究采用国标等方法对1～5年生黄花倒水莲根系形态特征、生物量、药用成分、营养成分和矿质元素进行了分析。结果表明：(1)根系形态(根幅、基径及一级根径)和根生物量在前2年增长缓慢，第2～3年增长迅速，第3年后趋于平缓。(2)不同药用成分含量在不同栽培年限间存在显著差异，其中粗多糖在第1年含量最高，皂苷类化合物在第2年含量最高，黄酮类化合物在第4年含量最高。(3)矿质元素含量受栽培年限影响较复杂，Ca、Mg、Mn、Cu含量在第3年累积至最多，Fe含量逐年降低，Pb含量与Fe含量变化规律相反。(4)粗蛋白含量呈现先增加后降低的趋势，总灰分含量与粗脂肪含量呈逐年降低趋势。(5)黄花倒水莲在第3年达到高产量，4～5年生黄花倒水莲根中大多品质指标均处于最低值，第3年为黄花倒水莲较为理想的采收期。该研究阐明了黄花倒水莲在不同栽培年限根系的产量指标及品质指标积累动态变化规律，揭示了黄花倒水莲的最佳采收期，为黄花倒水莲高产优质栽培提供了技术指导。     

黄花倒水莲栽培及利用研究综述

黄花倒水莲(Polygala fallax Hemsl.)为远志科远志属灌木或小乔木,以根入药,有健脾利湿、活血调经的功能。为更好开发利用黄花倒水莲资源,综述了其生物学特性、栽培与育种、组培快繁、化学成分和药理作用以及提取工艺等方面研究,并对黄花倒水莲丰产开发技术的研究方向作出展望。     

黄花倒水莲生长与内源激素水平动态变化关系研究北大核心CSCD

为探索黄花倒水莲春梢生理生化特性的差异以及不同内源激素的变化规律,该文对黄花倒水莲春梢的生长动态进行监测,采用间接酶联免疫吸附法(ELISA)测定脱落酸(ABA)、生长素(IAA)、赤霉素(GA)、乙烯(ETH)和玉米素核苷(ZR)五种内源激素含量的动态变化,并对两者间的相关性进行分析。结果表明:(1)黄花倒水莲春梢生长发育过程可分为快速增长期(0~12 d)、生长转折期(16~20 d)和缓慢增长期(24~32 d)三个阶段。(2)内源激素ABA、GA、ETH和ZR含量在缓慢增长期显著高于快速增长期和生长转折期,IAA含量各时期差异较小。(3)春梢长、底部叶长和叶宽在快速增长期与ABA、GA、ETH和ZR含量呈负相关,且与ZR含量具有一定显著性,与IAA含量呈正相关;生长转折期,各指标与GA、ETH和ZR含量呈正相关,与GA含量具有一定显著性,与ABA含量呈负相关;缓慢增长期,各指标与五种内源激素含量均呈正相关,与IAA和ZR含量具有一定显著性。该研究结果为生产上利用外源激素调控黄花倒水莲春梢抽出以及生长提供了理论基础。     

不同产地与类型及采收方法对黄花蒿中青蒿素含量的影响

以来源于重庆、广西、湖南、广东、江苏、陕西等省区的72分种质资源为试验材料,研究不同产地与类型及采收方法对黄花蒿中青蒿素含量的影响,为良种的选育和药材的采收提供科学的依据。结果表明:(1)早熟型与中、晚熟型青蒿素含量的差异显著,其顺序为:中熟型>晚熟型>早熟型;(2)在同一管理条件下不同茎秆颜色的青蒿素含量之间差异显著,其顺序为:白杆型>黄绿秆型>紫秆型>绿秆型;(3)不同产地的黄花蒿青蒿素含量动态变化规律一致,青蒿素含量最高时期为孕蕾期,是最佳采收期;(4)不同部位之间青蒿素含量差异显著,以叶片的青蒿素含量最高。     

黄花倒水莲内生真菌生物活性评价及HNLF-44菌株鉴定

为充分开发黄花倒水莲(Polygala fallax)的内生真菌资源，获得具有抗植物病原真菌、抗氧化活性的内生真菌，该文以黄花倒水莲内生真菌为研究对象，使用平板对峙法检测内生真菌对6种植物病原真菌的抑菌活性，测定内生真菌发酵液的DPPH清除自由基能力和总还原能力，评价内生真菌的抗氧化活性，并对具有强抑菌活性和抗氧化活性的菌株进行形态和ITS鉴定。结果表明：(1)黄花倒水莲内生真菌中有2株内生真菌对香蕉专化尖孢镰刀菌、柑橘树脂病菌、叶点霉菌、香蕉具条叶斑病菌、茄病镰刀菌、三七根腐病菌具有明显的抑菌活性，抑菌率在50.3%～91.4%之间，其中HNLF-5对柑橘树脂病菌的抑菌率为73.2%,HNLF-44对香蕉专化尖孢镰刀菌抑菌率为91.4%。(2)内生真菌发酵液具有良好的抗氧化活性，DPPH清除率均在80%以上，总还原能力吸光值范围为0.279 2～0.748 8。(3)HNLF-44菌株为链格孢属真菌。该研究表明，药用植物黄花倒水莲内生真菌具有较好的生物活性，为后续从黄花倒水莲内生真菌中挖掘潜在新型抑菌活性和抗氧化活性物质奠定了基础。     

不同产地无患子果皮皂苷含量的地理变异研究

通过对不同产地无患子果皮皂苷含量的测定分析,结果表明,14个产地间果皮皂苷含量差异显著,平均含量为8.85%。果皮皂苷含量与产地经度间存在显著性正相关,东西部产地果皮皂苷含量差异明显,西部产地平均含量高于东部产地。聚类分析结果亦表明,东西部产地间果皮皂苷含量出现明显分化,西南部产地的江西宜丰、贵州榕江、广西龙州分化尤为明显,表现出较高的皂苷含量,为无患子高皂苷含量筛选的优良产区。     

云南不同产地珠子参的品质评价研究

目的：研究不同产地野生珠子参的竹节参皂苷IVa和总皂苷的含量差异，结合农艺性状对三个不同产地珠子参的种质资源进行评价，为珠子参的栽培及优质种质的筛选提供理论基础。方法：以云南三个不同产地野生珠子参为研究对象，采用紫外分光光度法和试剂显色法测定珠子参中总皂苷的含量；采用高效液相色谱法（HPLC）测定珠子参中竹节参皂苷IVa的含量；采用民族植物学田野调查法研究云南三个不同产地珠子参的农艺性状。结果：云南三个不同产地的野生珠子参，以云南省丽江市玉龙县的野生珠子参中总皂苷和竹节参皂苷IVa的含量最高，其珠子参总皂苷的含量为15.21%±1.25%，珠子参中竹节参皂苷IVa的含量为4.78%±0.35%，农艺性状也相对较优。结论：不同产地的珠子参质量差异较大，云南省丽江市玉龙县的野生珠子参品质较好，具有较高的开发利用价值。     

龙牙楤木总皂苷含量测定及其抗炎镇痛活性评价

建立了一种龙牙楤木中总皂苷的含量测定方法,比较了龙牙楤木根皮和茎皮中总皂苷含量,并研究了龙牙愡木的抗炎镇痛作用。采用超声辅助提取,用紫外-可见分光光度法,以齐墩果酸为对照品建立标准曲线;以5%香草醛-冰醋酸为显色剂,检测波长550nm,用比色法测定总皂苷含量。结果显示所建立的方法稳定可靠,龙牙楤木不同部位皂苷含量差异较大,根皮总皂苷含量为43.50mg/g,而茎皮为24.38mg/g。总皂苷在0.02~0.10mg/mL(R~2=0.999 6)质量浓度范围内呈良好线性关系,根皮和茎皮的平均回收率分别为100.12%(RSD=1.10%)和99.84%(RSD=1.77%)。采用醋酸致小鼠扭体试验和耳廓肿胀试验研究龙牙楤木总皂苷抗炎镇痛活性,结果表明龙牙楤木总皂苷能显著减轻醋酸对试验小鼠内脏所致的疼痛(P<0.05)和降低由二甲苯所致实验小鼠耳廓的肿胀程度(P<0.05),显示出较强的抗炎镇痛作用,且根皮的作用效果比茎皮好。龙牙愡木抗炎镇痛活性可能与其总皂苷含量呈正相关。建立的总皂苷含量测定方法简便、准确、重现性好,可作为龙牙楤木根皮与茎皮中总皂苷的含量测定方法。     

HPLC法同时测定延胡索不同部位中11种核苷类成分

目的：测定并评价不同产地延胡索药材不同部位中11种核苷类成分的含量。方法：采用高效液相色谱法测定核苷类成分的含量，并对测定结果进行聚类分析。结果：不同产地延胡索中核苷类物质含量由高到低为鸟苷>尿苷>腺苷>肌苷>胞苷>尿嘧啶>2’-脱氧肌苷>2’-脱氧胸苷>腺嘌呤>胸腺嘧啶>2’-脱氧腺苷，11种核苷总含量整体表现为叶>茎>块茎，不同产地延胡索核苷类总含量由高到低为浙江磐安>浙江东阳>陕西汉中>重庆万州>重庆开州，块茎中的11种核苷成分含量比无显著性差异，但茎和叶差异较大。结论：此方法可用于延胡索不同部位中核苷类成分的测定，为其综合利用提供思路。     

鳢肠不同部位抗骨质疏松活性及化学成分比较研究

为了比较鳢肠不同部位提取物的抗骨质疏松活性及总皂苷、总黄酮含量,采用MTT法和对硝基苯酚磷酸二钠法测定鳢肠不同部位乙醇提取物对UMR106细胞的增殖和碱性磷酸酶(ALP)活性;采用紫外分光光度法测定鳢肠不同部位总皂苷和总黄酮含量。结果表明,鳢肠根和叶提取物对UMR106细胞的增殖具有促进作用,浓度为50μg/mL时促增殖作用最强,增值率分别为7.7%和16.9%,茎提取物没有明显的作用;鳢肠根、茎、叶提取物对ALP活性均有促进作用,浓度为100μg/mL时促增殖作用最强,分别促进18.9%、20.1%和17.0%;鳢肠根、茎、叶中总皂苷含量分别为3.6%、4.0%和2.2%,总黄酮含量分别为1.4%、1.4%和3.4%。这些结果表明;鳢肠不同部位提取物均有抗骨质疏松活性,其不同部位总皂苷和总黄酮的含量差异较大。     

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.