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991.
Yueqiang Leng Mingxia Zhao Rui Wang Brian J. Steffenson Robert S. Brueggeman Shaobin Zhong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(7):1531-1539
Key message
We identified, fine mapped, and physically anchored a dominant spot blotch susceptibility gene Scs6 to a 125 kb genomic region containing the Mla locus on barley chromosome 1H.Abstract
Spot blotch caused by Cochliobolus sativus is an important disease of barley, but the molecular mechanisms underlying resistance and susceptibility to the disease are not well understood. In this study, we identified and mapped a gene conferring susceptibility to spot blotch caused by the pathotype 2 isolate (ND90Pr) of C. sativus in barley cultivar Bowman. Genetic analysis of F1 and F2 progeny as well as F3 families from a cross between Bowman and ND 5883 indicated that a single dominant gene (designated as Scs6) conferred spot blotch susceptibility in Bowman. Using a doubled haploid (DH) population derived from a cross between Calicuchima-sib (resistant) and Bowman-BC (susceptible), we confirmed that Scs6, contributed by Bowman-BC, was localized at the same locus as the previously identified spot blotch resistance allele Rcs6, which was contributed by Calicuchima-sib and mapped on the short arm of chromosome 1H. Using a genome-wide putative linear gene index of barley (Genome Zipper), 13 cleaved amplified polymorphism markers were developed from 11 flcDNA and two EST sequences and mapped to the Scs6/Rcs6 region on a linkage map constructed with the DH population. Further fine mapping with markers developed from barley genome sequences and F2 recombinants derived from Bowman?×?ND 5883 and Bowman?×?ND B112 crosses delimited Scs6 in a 125 kb genomic interval harboring the Mla locus on the reference genome of barley cv. Morex. This study provides a foundational step for further cloning of Scs6 using a map-based approach.992.
Rui Xu Ganyuan Xiao Yan Li Hongyan Liu Qing Song Xiaoyu Zhang Ziyi Yang Yunxiaozhu Zheng Zhenghuai Tan Yong Deng 《Bioorganic & medicinal chemistry》2018,26(8):1885-1895
A series of 5,6-dimethoxybenzo[d]isothiazol-3(2H)-one-N-alkylbenzylamine derivatives were designed, synthesized and evaluated as potential multifunctional agents for the treatment of Alzheimer’s disease (AD). The in vitro assays indicated that most of these derivatives were selective AChE inhibitors with good multifunctional properties. Among them, compounds 11b and 11d displayed comprehensive advantages, with good AChE (IC50?=?0.29?±?0.01?μM and 0.46?±?0.02?μM, respectively), MAO-A (IC50?=?8.2?±?0.08?μM and 7.9?±?0.07?μM, respectively) and MAO-B (IC50?=?20.1?±?0.16?μM and 43.8?±?2.0% at 10?μM, respectively) inhibitory activities, moderate self-induced Aβ1–42 aggregation inhibitory potency (35.4?±?0.42% and 48.0?±?1.53% at 25?μM, respectively) and potential antioxidant activity. In addition, the two representative compounds displayed high BBB permeability in vitro. Taken together, these multifunctional properties make 11b and 11d as a promising candidate for the development of efficient drugs against AD. 相似文献
993.
Zhongcheng Cao Jie Yang Rui Xu Qin Song Xiaoyu Zhang Hongyan Liu Xiaoming Qiang Yan Li Zhenghuai Tan Yong Deng 《Bioorganic & medicinal chemistry》2018,26(5):1102-1115
A series of 4′-OH-flurbiprofen-chalcone hybrids were designed, synthesized and evaluated as potential multifunctional agents for the treatment of Alzheimer’s disease. The biological screening results indicated that most of these hybrids exhibited good multifunctional activities. Among them, compounds 7k and 7m demonstrated the best inhibitory effects on self-induced Aβ1–42 aggregation (60.0% and 78.2%, respectively) and Cu2+-induced Aβ1–42 aggregation (52.4% and 95.0%, respectively). Moreover, these two representative compounds also exhibited good antioxidant activities, MAO inhibitions, biometal chelating abilities and anti-neuroinflammatory activities in vitro. Furthermore, compound 7m displayed appropriate blood-brain barrier permeability. These multifunctional properties highlight compound 7k and 7m as promising candidates for further development of multi-functional drugs against AD. 相似文献
994.
中药在提取炮制后残留大量生物质被简单堆弃,而其中的木质纤维素等生物质能被微生物有效利用降解,筛选到16株对木质纤维素有降解效果的菌株,对其中8株降解效果明显功能菌株进行了深入研究,经16(18)S rDNA鉴定发现5株细菌主要为Bacillus属、Streptomyces属和Enterobacter属,3株真菌为Ascomycete属、Aspergillus属和Trichosporon属;利用8株菌固相发酵中药废弃物,通过监测堆体温度、pH等参数,发现细菌类在发酵初期能迅速提高堆体温度,而真菌类发酵腐熟过程较缓慢,提示利用细菌-真菌联合组成降解菌系是提高中药废弃物固相发酵的重要手段。 相似文献
995.
报道了鄂西湘西武陵山区区域内虎耳草科金腰属植物新记录种7种,其中湖北省新记录种有3种,分别为:天胡荽金腰(Chrysosplenium hydrocotylifolium Levl.et Vaniot.)、陕甘金腰(Chrysosplenium qinlingense Jien ex J.T.Pan)、毛金腰(Chrysosplenium pilosum Maxim.);湖南省新记录种4种,分别为:微子金腰(Chrysosplenium microspermum Franch)、中华金腰(Chrysosplenium sinicum Maxim)、山溪金腰(Chrysospleniumnepalense D.Don.)和绵毛金腰(Chr ysos plenium lanu gino-sum Hook.f.et Thoms.).上述金腰属植物均提供了经纬度、海拔及植物照片,引证标本存放于中南民族大学植物标本馆(HSN). 相似文献
996.
为揭示毛竹入侵邻域林分过程中对土壤细菌群落多样性变化的影响,以马尾松林为研究对象,采集纯毛竹林、竹针混交林和常绿针叶(马尾松)混交林3类样地的混合土样,基于高通量测序技术分析土壤细菌群落多样性和结构变化.结果表明: 研究期间共得到细菌类群39门88纲134目160科511属;在门的分类水平上,与竹针混交林、常绿针叶混交林相比,纯毛竹林酸杆菌门所占比例显著较低,而放线菌门、拟杆菌门、TM7和衣原体门所占比例较高;在属的分类水平上,相对于纯毛竹林,竹针混交林和常绿针叶混交林均有多属表现出所占比例显著上升或下降,单独出现在竹针混交林或常绿针叶混交林且所占比例在0.005%~0.1%的非优势属有130属;α多样性指数均表现为常绿针叶混交林>竹针混交林>纯竹林,且纯竹林与两者均有显著差异,而常绿针叶混交林和竹针混交林之间差异不显著.PCoA分析表明,毛竹入侵对土壤细菌的种群多样性和群落结构产生了影响;所占比例小于0.1%的非优势菌群门分类水平的百分比特征与土壤环境梯度(水溶性有机氮和硝态氮)之间有显著相关性,两者对毛竹入侵马尾松林后土壤细菌群落的非优势种群影响巨大,具有重要的参考价值. 相似文献
997.
998.
999.
Polycyclic aromatic hydrocarbons (PAHs) have become a major type of persistent organic pollutant (POPs) in the world. To well understand the occurrence, spatial distribution and source apportionment of 16 PAHs in different media in Beijing, a comprehensive study was conducted based on 337 obtained and subsequently selected samples in four specific media, including soil, road dust, surface water and atmosphere covering sampling time spanning from 2005 to 2014. Mean concentrations of Σ16 PAHs in soils (878.5 μg/kg) decreased from inner city to exterior areas with different land uses decreased in the order of industrial estate (2510 μg/kg)>educational area (1331 μg/kg)>Park (783 μg/kg)>cultivated (650 μg/kg)>roadside (583 μg/kg)>residential (568 μg/kg)>green area (478 μg/kg)>forest area (125 μg/kg). Meanwhile, PAHs concentrations in branch roads were slightly higher than trunk roads and mainly concentrated in urban areas (1136 μg/kg). Affected by industrial and residential areas, PAHs concentrations in downstream surface rivers were much higher than upstream surface rivers (475 ng/L). Due to strong mobility, PAHs concentrations in atmosphere were not equally distributed around the study area (157.59 ng/m3). The result of source apportionment determined by diagnostic ratios method indicated PAHs in multiple media in Beijing are mainly from coal and biomass combustion. 相似文献
1000.
To investigate the occurrences of polychlorinated biphenyls (PCBs) in suburban vegetable soils of Changchun area, Northeast China, 106 urban vegetable soil samples were collected from Changchun City, Nongan County, Dehui City, Yushu City, Jiutai City, Shuangyang District. We analyzed the concentrations, compositions and sources of 7 PCBs in top soils of Changchun area, and evaluated the non-carcinogenic and carcinogenic risk of PCBs pollution to exposed population. The total concentrations of 7 PCBs ranged from 1.31 to 148 ng/g dry weight (dw) with a mean value of 42.0 ng/g and dominated by Hepta-CBs and Penta-CBs. Principal component analysis (PCA) revealed that PCB pollution in soils of Changchun area mainly related to transportation, vehicle emissions, paints and other industries. Human health risk assessment showed that the cumulative non-carcinogenic and the cumulative carcinogenic risk in children and adults in the industrial land and residential land were acceptable, considering only 7 PCBs homologues were analyzed in this study, the actual risk could be higher. 相似文献