Semi-Synthesis,Cytotoxic Evaluation,and Structure—Activity Relationships of Brefeldin A Derivatives with Antileukemia Activity     

Xu-Xiu Lu  Yao-Yao Jiang  Yan-Wei Wu  Guang-Ying Chen  Chang-Lun Shao  Yu-Cheng Gu  Ming Liu  Mei-Yan Wei 《Marine drugs》2022,20(1)

Brefeldin A (1), a potent cytotoxic natural macrolactone, was produced by the marine fungus Penicillium sp. (HS-N-29) from the medicinal mangrove Acanthus ilicifolius. Series of its ester derivatives 2–16 were designed and semi-synthesized, and their structures were characterized by spectroscopic methods. Their cytotoxic activities were evaluated against human chronic myelogenous leukemia K562 cell line in vitro, and the preliminary structure–activity relationships revealed that the hydroxy group played an important role. Moreover, the monoester derivatives exhibited stronger cytotoxic activity than the diester derivatives. Among them, brefeldin A 7-O-2-chloro-4,5-difluorobenzoate (7) exhibited the strongest inhibitory effect on the proliferation of K562 cells with an IC₅₀ value of 0.84 µM. Further evaluations indicated that 7 induced cell cycle arrest, stimulated cell apoptosis, inhibited phosphorylation of BCR-ABL, and thereby inactivated its downstream AKT signaling pathway. The expression of downstream signaling molecules in the AKT pathway, including mTOR and p70S6K, was also attenuated after 7-treatment in a dose-dependent manner. Furthermore, molecular modeling of 7 docked into 1 binding site of an ARF1–GDP-GEF complex represented well-tolerance. Taken together, 7 had the potential to be served as an effective antileukemia agent or lead compound for further exploration.  相似文献   

Exogenous application of melatonin improves plant resistance to virus infection     

L. Zhao  L. Chen  P. Gu  X. Zhan  Y. Zhang  C. Hou  Z. Wu  Y.-F. Wu  Q.-C. Wang 《Plant pathology》2019,68(7):1287-1295

In this study, melatonin (MEL)-mediated plant resistance to tobacco mosaic virus (TMV) was examined to study local infection in Nicotiana glutinosa and systemic infection in Solanum lycopersicum. Exogenous application of 100 µm MEL increased anti-virus infection activity to 37.4% in virus-infected N. glutinosa plants. The same treatment significantly reduced relative levels of virus RNA analysed by qRT-PCR and virus titres measured by dot-ELISA, and increased the relative expression levels of the PR1 and PR5 genes analysed by qRT-PCR, in virus-infected S. lycopersicum. MEL treatment induced considerable accumulations of salicylic acid (SA) and nitric oxide (NO) but did not significantly affect production of hydrogen peroxide (H₂O₂) in the virus-infected S. lycopersicum plants. Transgenic nahG N. tabacum was used to determine whether MEL-induced TMV resistance was dependent on the SA pathway. The results showed that the relative RNA level of the TMV analysed by qRT-PCR and virus titres analysed by dot-ELISA were not reduced by the MEL treatment in the nahG transgenic N. tabacum seedlings treated twice with 100 µm MEL. The increased relative expression levels of PR1 and PR5 were greatly reduced when cPTIO, an NO scavenger, was included in the MEL treatment. A working model of MEL-mediated plant resistance to TMV is proposed. MEL-mediated plant resistance to viruses provides a new avenue to control plant viral diseases.  相似文献   

喷头和施药液量对水稻植株上农药沉积和药剂防治效果的影响   总被引：2，自引：0，他引：2  

徐德进  徐广春  许小龙  徐鹿  顾中言  邱白晶 《植物保护学报》2019,46(2):409-416

为明确喷头及施药液量对水稻植株上农药沉积及药剂防治效果的影响,采用丽春红-G示踪法测定了4种喷头ST11001、ST11002、TR8001、TR8002在不同施药液量条件下喷雾农药在水稻植株上的沉积分布特性,并比较了4种喷头施用相同剂量的40%氯虫苯甲酰胺·噻虫嗪WDG对水稻纵卷叶螟Cnaphalocrocis medinalis和褐飞虱Nilaparvata lugens的防治效果。结果表明,选择ST11002和TR8001喷头,在施药液量300 L/hm~2条件下喷雾,单株水稻上的丽春红-G沉积量分别达到27.55μg和28.16μg;选择ST11001和TR8002喷头,在施药液量900 L/hm~2条件下喷雾,单株水稻上的丽春红-G沉积量仅分别为12.27μg和14.86μg。喷头和施药液量的改变不影响水稻植株上农药沉积分布特性,均为上层沉积量中层沉积量下层沉积量。当施药液量从300 L/hm~2增加到900 L/hm~2,4种喷头ST11001、ST11002、TR8001、TR8002喷雾在水稻基部的雾滴密度分别增加了8.21、8.54、7.79和9.69倍;但在相同施药液量下,4种喷头在水稻基部的雾滴密度没有显著差异。同一剂量下,喷头和施药液量不同组合的防治效果间差异显著。表明针对稻田不同防治对象,选择合适的喷头及施药液量将有助于提高农药沉积及防治效果。  相似文献   

Transport‐induced changes in hypothalamic–pituitary–interrenal axis gene expression and oxidative stress responses in Coilia nasus          下载免费PDF全文

Fukuan Du  Gangchun Xu  Jinwei Gao  Zhijuan Nie  Pao Xu  Ruobo Gu 《Aquaculture Research》2016,47(11):3599-3607

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植物收割对人工湿地基质酶活性的影响     

曾梦兆  李谷  吴恢碧  陶玲  姚雁鸿 《淡水渔业》2008,38(2):51-53,45

研究了7月份植物收割对人工湿地基质磷酸酶、脲酶、蛋白酶、脱氢酶活性及养殖废水中总氮(TN)、总磷(TP)、COD去除率的影响。结果显示:植物收割后磷酸酶、脲酶、蛋白酶活性开始增高,分别于第20天(13.7 mg/100 g)、第16天(1.9 mg/100 g)、第12天(61.7 mg/100 g)达到最大值,均于第28天(10.1 mg/100 g、1.1 mg/100 g、43.2 mg/100 g)恢复到收割前水平。脱氢酶活性在植物收割后第4天(142.3μL/100 g)降到最小值,此后开始增高,第16天(249.5μL/100 g)达到最大值,于第24天(195.6μL/100 g)恢复到收割前水平。净化效果研究表明,植物收割后TP、TN去除率开始增高,分别在植物收割后第20天(75.1%)、16天(60.6%)达到最大值,均于第28天(51.1%、34.1%)恢复到收割前水平。COD去除率在收割后第4天(25.3%)降到最小值,此后开始增高,第16天(70.2%)达到最高值,第24天(46.5%)恢复到收割前水平。  相似文献   

刺参南移与人工育苗试验   总被引：4，自引：0，他引：4  

肖树旭  顾功超 《水产学报》1981,5(2):147-154

本文报道了将刺参从山东南移到厦门的试验结果及在人工饲养条件下的生长、发育和度夏情况,并介绍了人工培育刺参幼体的几种方法。  相似文献   

鲤IGF-Ⅰ基因2个高度多态微卫星位点的鉴定及其与生长相关性状的关联分析     

胡雪松  于淼  李池陶  贾智英  石连玉 《中国水产科学》2014,21(5)

利用PCR结合测序方法,在鲤(Cyprinus carpio)类胰岛素生长因子-Ⅰ(insulin-like growth factor-Ⅰ,IGF-Ⅰ)基因内含子1和内含子2中各鉴定1个微卫星多态性位点,分别命名为intron1189和intron2310,这两个位点均以4碱基为重复单元.以黑龙江鲤(Cyprinus cario haematopterus,YL)(n=263)、德国镜鲤选育系(Cyprinus carpio L.mirror,JL)(n=229),及荷包红鲤抗寒品系(Cyprinus carpio var.wuyuanensis,HL)(n=255)为研究对象,评估了这两个位点不同基因型(频率＞3％)与鲤4个生长时段(135 d、325 d、335 d和445 d)生长表型的关联.结果显示,2个位点在3个鲤群体中均表现为高度多态(PIC＞0.5).intron1189位点多态性主要对YL的135 d、325 d体长和325 d、385 d体质量有显著影响(P＜0.05),而intron2 310位点多态性对JL各检测时段的体长和体质量均有显著影响(P＜0.05).对不同基因型个体的体长和体质量性状进行多重比较,结果显示,在intron 1189位点,185/229基因型YL的135 d、325 d体长和325 d、385 d体质量最低,而205/221基因型YL的135 d、325 d体长和325 d体质量最高.在mtron2310位点,290/350基因型JL在各检测时段的体长及135 d、325 d、385 d体质量最低,而318/350基因型JL的135 d、325 d、385 d体长和体质量均为最高.上述结果表明,鲤IGF-Ⅰ基因内含子中的这两个高度多态微卫星位点潜在影响鲤的生长性能.  相似文献   

池塘养殖尾水经稻田生态工程净化后的浮游细菌群落特征     

陶玲  李晓丽  朱建强  李谷 《淡水渔业》2017,47(1):71-77

为利用稻田生态工程对精养池塘尾水进行循环利用,采用Illumina Mi Seq第二代测序技术比较分析了稻田生态工程进出水中浮游细菌群落结构和多样性差异,以探讨稻田生态工程净化回用水中浮游细菌群落变化对池塘养殖的影响。结果显示,稻田生态工程进出水中优势浮游细菌在门水平上的组成相同,均为蓝细菌门(Cyanobacteria)、变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、浮霉菌门(Planctomycetes)和拟杆菌门(Bacteroidetes)。但优势门类的相对丰度发生变化,蓝细菌门的相对丰度由进水中的46.72%显著降低至表面流出水中的41.82%和渗流出水中的34.77%;而放线菌门的相对丰度由3.90%增加至表面流出水中的5.65%和渗流出水中的6.45%。属水平上优势浮游细菌组成也相同,但微囊藻属(Microcystis)的相对丰度由0.83%显著降低至渗流出水中的0.46%(P0.05)。另外,稻田生态工程表面流出水中浮游细菌物种丰富度指数(Chao 1)显著提高,渗流出水中Shannon多样性指数显著提高,且Simpson指数显著降低(P0.05)。  相似文献   

转Bt-基因棉棉仁粉对鲤鱼营养价值的研究     

李谷  陈松  游文章  黄骏麒  吴建开  张震林  文华  周宝良 《水产科学》2000,19(5):6-9

为评估转Ｂｔ－基因棉棉仁粉用作鱼饲料的有效性和安全性,将其配成试验饲料进行了１４周鲤鱼喂养,前８周着重就鲤钱垢增重率、特定生长率、铒料系数、鱼体化学成分含量等营养学指标进行了观察。上述各项指标经统计分析,在试验组和对照组之间均无显著性差异。表明转Ｂｔ－基因棉棉仁粉经脱棉酚处理后,与常规棉棉仁粉一样可作鱼用饲料的蛋白源。  相似文献   

大头鲤、黑龙江鲤、德国镜鲤及其杂种F3肌肉品质的比较   总被引：3，自引：0，他引：3  

李池陶  关海红  胡雪松 《水产学报》2008,32(1):45-50

对大头鲤、黑龙江鲤、德国镜鲤及杂种F3背部肌肉的肉色、嫩度、pH、失水率、系水力和肌纤维性状进行研究,评价杂种F3的肌肉品质.结果表明:(1)杂种F3肌肉的亮度为47.37,红度为1.85,黄度3.27,嫩度为1.65 kg·f,pH 6.62,失水率为22.54%,系水力为97.30%,肌纤维的横截面积为128.76 μm2,纤维的密度为每平方毫米183.38根,肌纤维面积的比例为55.55%.(2)杂种F3与亲本肌肉品质的比较,肉色亮度与黑龙江鲤相近,高于大头鲤和德国镜鲤;红度与大头鲤和黑龙江鲤相近,低于德国镜鲤;嫩度与大头鲤相近,小于黑龙江鲤和德国镜鲤;肌纤维的横截面积与大头鲤相近,小于黑龙江鲤和德国镜鲤;肌纤维密度与大头鲤相近,大于黑龙江鲤和德国镜鲤;pH、失水率、系水力、肉色的黄度和肌纤维面积的比例与3亲本差异不显著.研究表明杂种F3具有与大头鲤相似的肌肉品质,经进一步选育可以育成一个优质的鲤新品系.  相似文献