A major genome region underlying artemisinin resistance in malaria     

Cheeseman IH  Miller BA  Nair S  Nkhoma S  Tan A  Tan JC  Al Saai S  Phyo AP  Moo CL  Lwin KM  McGready R  Ashley E  Imwong M  Stepniewska K  Yi P  Dondorp AM  Mayxay M  Newton PN  White NJ  Nosten F  Ferdig MT  Anderson TJ 《Science (New York, N.Y.)》2012,336(6077):79-82

Evolving resistance to artemisinin-based compounds threatens to derail attempts to control malaria. Resistance has been confirmed in western Cambodia and has recently emerged in western Thailand, but is absent from neighboring Laos. Artemisinin resistance results in reduced parasite clearance rates (CRs) after treatment. We used a two-phase strategy to identify genome region(s) underlying this ongoing selective event. Geographical differentiation and haplotype structure at 6969 polymorphic single-nucleotide polymorphisms (SNPs) in 91 parasites from Cambodia, Thailand, and Laos identified 33 genome regions under strong selection. We screened SNPs and microsatellites within these regions in 715 parasites from Thailand, identifying a selective sweep on chromosome 13 that shows strong association (P = 10(-6) to 10(-12)) with slow CRs, illustrating the efficacy of targeted association for identifying the genetic basis of adaptive traits.  相似文献   

Spiders (Araneae) in the pesticide world: an ecotoxicological review     

Stano Pekár 《Pest management science》2012,68(11):1438-1446

Being one of the most abundant and species‐rich groups of natural enemies occurring in all agroecosystems, spiders are variably affected by pesticide applications. Here, a review is given of research on spider ecotoxicology. More than 40 species of spiders and almost 130 pesticides (acaricides, insecticides, fungicides and herbicides) have been tested so far in the field or under laboratory conditions. Field studies show that the degree of population reduction following pesticide application is a function of a number of factors inherent to pesticides, crops and spider species (guilds). These studies also revealed indirect effects via habitat and prey disruption. Among laboratory studies, a number of papers have investigated only the direct lethal effect. A meta‐analysis of these data reveals that spiders are mainly affected by acaricides and insecticides, particularly neurotoxic substances. Currently, ecotoxicological research on spiders is focused more on direct sublethal effects on a variety of behavioural traits (locomotion, predation, web‐building, reproduction, development) and physiology. Yet a standardised approach to the evaluation of sublethal effects is lacking. A few studies have provided some evidence for hormesis in spiders. Future research should be more concentrated on sublethal effects and the estimation of long‐term changes in spider populations as a result of pesticide treatment. Copyright © 2012 Society of Chemical Industry  相似文献   

油茶良种‘华鑫’   总被引：1，自引：0，他引：1  

谭晓风  袁德义  邹锋  袁军  谢鹏  苏勇  王渊  杨定桃  彭建桃 《林业科学》2012,48(3):170-171

‘华鑫’是从普通油茶实生林分中选育的高产油茶良种,属霜降籽类型,鲜果平均单果质量48.83g,最大单果质量66.30g,鲜出籽率52.56%,干籽含油率39.97%,盛果期产量1050kg·hm-2以上,具有高产、稳产、抗性强等特点。  相似文献   

Tyrosinase inhibition constituents from the roots of Morus australis     

Zheng ZP  Tan HY  Wang M 《Fitoterapia》2012,83(6):1008-1013

The phytochemical profiles of Morus australis roots, stems and twigs were firstly compared by HPLC analysis. It was found that Morus australis stem extract mainly contained one known tyrosinase inhibitor, oxyresveratrol, while its root and twig extract might contain some unknown potential tyrosinase inhibitors. The root extract of Morus australis was further investigated in this study. One new compound, austraone A, together with 21 known compounds, was isolated and their structures were identified by interpretation of MS and NMR data. In the tyrosinase inhibitory testing, some of them, such as oxyresveratrol, moracenin D, sanggenon T, and kuwanon O, exhibited stronger tyrosinase inhibitory activities than that of kojic acid. These results suggested the Morus australis root extract as a good source of natural tyrosinase inhibitors with a great potential to be used in foods as anti-browning agents and in cosmetics as skin-whitening agents.  相似文献   

Cytotoxic sesquiterpenes and lignans from Saussurea deltoidea     

Xu JJ  Huang HQ  Zeng GZ  Tan NH 《Fitoterapia》2012,83(6):1125-1130

Two new sesquiterpenes deltoiden A (1) and deltoiden B (2), and two new lignans deltoignan A (9) and deltoignan B (10), together with 14 known compounds, including six sesquiterpenes 3-8 and three lignans 11-13, were isolated from the whole plant of Saussurea deltoidea. Compounds 3-8 and 11-17 were isolated for the first time from this plant. Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Cytotoxicities of compounds 1-13 were tested against three cancer cell lines A549, Hela and SMMC-7721. Results showed that 5, 6 and 7 exhibited cytotoxicity against SMMC-7721 with the IC(50) values of 6.49, 9.53, 1.23 μg/ml, 5 and 7 against A549 with the IC(50) values of 4.99 and 5.35 μg/ml, 5, 6, 7, 13 against Hela with the IC(50) values of 1.40, 4.75, 0.93 and 5.42 μg/ml, respectively. The structure-activity relationships of sesquiterpenes 1-8 were discussed on the base of cytotoxic results.  相似文献   

Neuroprotective activity of galloylated cyanogenic glucosides and hydrolysable tannins isolated from leaves of Phyllagathis rotundifolia     

Tan HP  Wong DZ  Ling SK  Chuah CH  Kadir HA 《Fitoterapia》2012,83(1):223-229

The galloylated cyanogenic glucosides based on prunasin (1-7), gallotannins (8-14), ellagitannins (15-17), ellagic acid derivatives (18, 19) and gallic acid (20) isolated from the leaves of Phyllagathis rotundifolia (Melastomataceae) were investigated for their neuroprotective activity against hydrogen peroxide (H₂O₂)-induced oxidative damage in NG108-15 hybridoma cell line. Among these compounds, the gallotannins and ellagitannins exhibited remarkable neuroprotective activities against oxidative damage in vitro as compared to galloylated cyanogenic glucosides and ellagic acid derivatives in a dose-dependent manner. They could be explored further as potential natural neuroprotectors in various remedies of neurodegenerative diseases.  相似文献   

Maternal supply of cysteamine alleviates oxidative stress and enhances angiogenesis in porcine placenta     

Shuangbo Huang  Zifang Wu  Zihao Huang  Xiangyu Hao  Longmiao Zhang  Chengjun Hu  Jianfu Wei  Jinping Deng  Chengquan Tan 《畜牧与生物技术杂志(英文版)》2022,(1):181-196

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日粮纤维的营养学功能及对母猪产仔数的影响   总被引：1，自引：0，他引：1  

谭成全  孙海清  彭健 《饲料工业》2012,(19):17-22

母猪繁殖性状主要包括总产仔数、产活仔数、初生个体均重及初生窝重、泌乳力、断奶仔猪数、断奶个体均重及断奶窝重,其中,产仔数是最重要的繁殖力评定指标。日粮纤维对家畜的营养物质的消化率存在负面影响,但是近半个世纪以来由于日粮纤维独特的性质在母猪的营养研究中备受关注。文中将从日粮纤维的定义及分析方法、理化特性着手,阐述日粮纤维添加到母猪妊娠日粮中对产仔数的影响并分析其可能原因。  相似文献   

厚朴林下轮作玄参、大黄种植技术研究   总被引：1，自引：1，他引：0  

林孝培侯义梅  谭勋桃彭建雄 曾美 《湖北林业科技》2012,(4):14-17

为更好地指导厚朴规范化种植,充分利用土地资源,大力发展林下经济,增加农民收入。2002年,在龙坪乡开展了厚朴林下轮作玄参、大黄种植模式和厚朴单作种植模式对比试验研究。试验结果表明:在厚朴林下轮作玄参、大黄种植模式下,厚朴各测树因子及皮产量较对照具有明显地增长和增产作用,同时每个轮作期内比对照增产大黄药材520 kg/666.7 m2、玄参药材320 kg/666.7 m2。  相似文献   

Arcgis视域分析在鹿门寺景区林火视频监控中的应用     

张源长谭正刚  万丽娟孔红霞 朱玫 《湖北林业科技》2012,(2):31-33

利用Arcgis地理信息系统平台,运用空间分析技术手段,以湖北襄阳鹿门寺景区地形图和卫星影像等数据为基础,选择不同观测点进行视域分析,设定了景区林火视频监控摄像头的位置,为森林防火管理辅助决策提供了依据。  相似文献