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Antibacterial compounds from Rutaceae with activities against Flavobacterium columnare and Streptococcus iniae

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Journal of Agricultural Chemistry and Environment 2013年第4期2卷 90-100页

作者： Kumudini M. Meepagala kevin K. schrader Charles L. Burandt University of Mississippi National Center for Natural Products Research University MS USA USDA-ARS Natural Products Utilization Research Unit University MS USA

From the ethyl acetate extract of Murraya koenegii (Rutaceae) leaves, isomahanine (1) and mahanine (2) were isolated that showed antibacterial activity towards Flavobacterium columnare and Streptococcus iniae which caused columnaris disease and streptococcosis respectively. Isomahanine was found to have the strongest activity against F. columnare (isolate ALM-00-173) and S. iniae (isolate LA94-426) based on 24-h 50% inhibition concentration (IC50) and minimum inhibition concentration (MIC). Although compound (7), a nicotinamide isolated from Amyris texana had the lowest MIC (2.8 ± 0 mg/L) of any of the test compounds against F. columnare, the 24-h IC50 of 14.8 ± 0.6 mg/L was higher than that of isomahanine and subsequently the 24-h IC50 RDC values for (7) were almost a magnitude of order higher than those obtained for isomahanine. Isomahanine also had the strongest activity against S. iniae, with a 24-h IC50 of 1.3 ± 0.1 mg/L and MIC of 3.5 ± 0 mg/L, respectively.

关键词： Murraya koenigii Amyris texana Piper nigrum Columnaris Disease Flavobacterium columnare Streptococcosis Streptococcus iniae Aquaculture

Evaluation of the toxicity of Streptomyces aburaviensis (R9) extract towards various agricultural pests

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Agricultural Sciences 2011年第4期2卷 491-497页

作者： Ismail Saadoun Sereen Bataineh Qutaiba Ababneh Khalid Hameed kevin schrader Charles Cantrell Franck Dayan David Wedge 不详

The dichloromethane extract of culture filtrate from Streptomyces aburaviensis R9 was evaluated using various rapid bioassays to determine potential inhibitory effects towards phytopathogenic fungi (Colletotrichum acutatum, C. fragariae, C. gloeosoprioids, Botrytis cinerea, Fusarium oxysporum, Phomopsis viticola and P. obscurans), fish bacterial pathogens (Edwardsiella ictaluri and Flavobacterium columnare), a green alga (Selenastrum capricornutum), plant seeds [Bent grass (Agrostis sp.) monocot and lettuce (Lactuca sativa) dicot] and 2-methylisoborneol (MIB)-producing cyanobacteria (Planktothrix perornata and Pseudanabaena sp.). The dichloromethane extract showed selective inhibition against the cyanobacterium P. perornata, with a lowest-complete-inhibition concentration (LCIC) of 10 mg/L and lowest-observed-effect concentration (LOEC) of 10 mg/L while LCIC and LOEC values were 100 mg/L when tested against S. capricornutum. This extract also showed slight meristematic cytogenic necrosis at 200 mg/L towards germinated seeds of both test plants. The compounds were not very toxic towards the channel catfish (Ictalurus punctatus) pathogenic bacteria E. ictaluri and F. columnare. Preliminary evaluation of the extract toward C. acutatum, C. fragariae and C. gloeosoprioids using TLC bioautography revealed moderate activity. However, further evaluation of the extract using a microtiter plate bioassay determined that inhibition was strongest against C. acutatum and C. fragariae, though this inhibitory activity diminished at 72 hours and was moderately less active than the commercial fungicides azoxystrobin and captan when comparing 1 - 100 mg/L levels at 48 hours.

关键词： Algae Catfish Cyanobacteria Fungi Pathogens Streptomyces

Algae and Aquatic Plants as Sources of New Agrochemicals

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Algae and Aquatic Plants as Sources of New Agrochemicals

Lipid nanoparticles deliver mRNA to the blood-brain barrier

The First Asia—Pacific Conference on Chemical Ecology

作者： Dale G.Nagle David E.Wedge kevin K.schrader Ira Rajbhandari Department of Pharmacognosy and National Center for the Development of Natural Products Research Institute of Pharmaceutical SciencesSchool of PharmacyThe University of MississippiUniversityMS38677USA USDA-ARS Natural Products Utilization Research Unit:The National Center for the Development of Natural Products The University of MississippiUniversityMS38677USA

＜正＞Microbial pests continue to represent major problems for the agriculture and aquaculture industries. Fungicide resistant fungal pathogens threaten ***,cyanobacteria（blue-green algae） bloom in aquaculture ponds and certain species can produce noxious or toxic chemicals that pose a particular problem for fish *** environmentally friendly methods to control microbial pests are urgently needed. We have established a program that focuses on the discovery of new naturally-derived agents to control

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Nano Research 2024年第10期17卷 9126-9134页

作者： Yanina Kuzminich Avraham Shakked Randi Calkins Sebastian Rudden Camille Jones Jessie Doan Bora Jang Elisa schrader Echeverri Ryan Zenhausern Liming Lian David Loughrey Hannah E.Peck Rachelle Wiese Dorothy Koveal Philip J.Santangelo James E.Dahlman George C.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Parker H.Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA Wallace H.Coulter Department of Biomedical Engineering Emory University School of Medicine and Georgia Institute of TechnologyAtlantaGA 30332USA

Lipid nanoparticles(LNPs)have delivered RNA to hepatocytes in patients after intravenous *** clinical data support efforts to design LNPs that transfect cells in the central nervous system(CNS).However,delivery to the CNS has been difficult,in large part because quantifying on-target delivery alongside common off-target cell types in adult mice remains *** we report methods to isolate different cell types from the CNS,and subsequently present mRNA delivery readouts using a liver-detargeted *** data suggest that LNPs without targeting ligands can transfect cerebral endothelial cells in mice after intravenous *** the difficulty of crossing the blood-brain barrier,they also underscore the value of quantifying delivery in the CNS with cell-type resolution instead of whole-tissue resolution.

关键词： lipid nanoparticle mRNA nanomedicine central nervous system blood-brain barrier

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生物活性指导下的白芷中抗真菌香豆素的分离

生物活性指导下的白芷中抗真菌香豆素的分离

Evaluation of the toxicity of Streptomyces aburaviensis (R9) extract towards various agricultural pests

2013全国中药与天然药物高峰论坛暨第十三届全国中药和天然药物学术研讨会

作者：谢谦李顺祥江星明廖端芳王炜 Abass Ali kevin K.schrader Stephen O.Duke Charles L.Cantrell David E.Wedge 湖南中医药大学药学院 National Center for Natural Products Research University of Mississippi USDA-ARS-NPURU University of Mississippi

目前,从天然产物中发现新型农药用于病虫害管理已成为可能,但是从传统中药中发现的新化学物质很少在生物农药领域做活性测试。白芷,早在公元前400年被记载用其根茎治疗的疾病,如头痛,鼻塞,解毒的血,牙龈肿痛,牙痛,消炎剂,润肠通便,镇静...

目前,从天然产物中发现新型农药用于病虫害管理已成为可能,但是从传统中药中发现的新化学物质很少在生物农药领域做活性测试。白芷,早在公元前400年被记载用其根茎治疗的疾病,如头痛,鼻塞,解毒的血,牙龈肿痛,牙痛,消炎剂,润肠通便,镇静,皮肤真菌感染,白芷也被广泛认为含有呋喃香豆素成分。

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Assessing the reproductive health of men with occupational exposures

Agricultural Sciences（农业科学） 2011年第4期

作者： Ismail Saadoun Sereen Bataineh Qutaiba Ababneh Khalid Hameed kevin schrader Charles Cantrell Franck Dayan David Wedge

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Asian Journal of Andrology 2014年第1期16卷 23-30页

作者： Steven M schrader Katherine L Marlow Centers for Disease Control and Prevention National Institute for Occupational Safety and Health Division of Applied Research and Technology Cincinnati OH USA.

The earliest report linking environmental （occupational） exposure to adverse human male reproductive effects dates back to1775 when an English physician, Percival Pott, reported a high incidence of scrotal cancer in chimney sweeps. This observation led to safety regulations in the form of bathing requirements for these workers. The fact that male-mediated reproductive harm in humans may be a result of toxicant exposures did not become firmly established until relatively recently, when Lancranjan studied lead-exposed workers in Romania in 1975, and later in 1977, when Whorton examined the effects of dibromochloropropane （DBCP） on male workers in California. Since these discoveries, several additional human reproductive toxicants have been identified through the convergence of laboratory and observational findings. Many research gaps remain, as the pool of potential human exposures with undetermined effects on male reproduction is vast. This review provides an overview of methods used to study the effects of exposures on male reproduction and their reproductive health, with a primary emphasis on the implementation and interpretation of human studies. Emphasis will be on occupational exposures, although much of the information is also useful in assessing environmental studies, occupational exposures are usually much higher and better defined.

关键词： accessory glands endocrine epidemiology semen sexual function sperm testis toxicology

Quantifyingα-diversity as a continuous function of location——a case study of a temperate forest

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林业研究:英文版 2023年第6期34卷 1683-1691页

作者： Peijian Shi Brady K.Quinn Long Chen Jie Gao Julian schrader Bamboo Research Institute College of Ecology and EnvironmentNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Tropical Silviculture and Forest Ecology University of GottingenBusgenweg 137077 GottingenGermany St.Andrews Biological Station Fisheries and Oceans Canada125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China School of Natural Sciences Macquarie UniversitySydneyNSW 2109Australia Biodiversity Macroecology&BiogeographyUniversity of GottingenBusgenweg 137077 GottingenGermany

α-diversity describes species diversity at local *** Simpson’s and Shannon-Wiener indices are widely used to characterizeα-diversity based on species abundances within a fixed study site(e.g.,a quadrat or plot).Although such indices provide overall diversity estimates that can be analyzed,their values are not spatially continuous nor applicable in theory to any point within the study region,and thus they cannot be treated as spatial covariates for analyses of other ***,we extended the Simpson’s and Shannon-Wiener indices to create point estimates ofα-diversity for any location based on spatially explicit species occurrences within different bandwidths(i.e.,radii,with the location of interest as the center).For an arbitrary point in the study region,species occurrences within the circle plotting the bandwidth were weighted according to their distance from the center using a tri-cube kernel function,with occurrences closer to the center having greater weight than more distant *** novel kernel-basedα-diversity indices were tested using a tree dataset from a 400 m×400 m study region comprising a 200 m×200 m core region surrounded by a 100-m width buffer *** newly extendedα-diversity indices did not disagree qualitatively with the traditional indices,and the former were slightly lower than the latter by<2%at medium and large band *** present work demonstrates the feasibility of using kernel-basedα-diversity indices to estimate diversity at any location in the study region and allows them to be used as quantifiable spatial covariates or predictors for other dependent variables of interest in future ecological *** continuousα-diversity indices are useful to compare and monitor species trends in space and time,which is valuable for conservation practitioners.

关键词： Distance-based weighting Diversity continuum Kernel function Shannon-Wiener index Simpson’s index Tri-cube kernel

An elliptical blade is not a true ellipse,but a superellipse–Evidence from two Michelia species

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Journal of Forestry Research 2022年第4期33卷 1341-1348页

作者： Yuping Li Karl JNiklas Johan Gielis Ülo Niinemets Julian schrader Rong Wang Peijian Shi College of Horticulture Jinling Institute of TechnologyNanjing 210038People’s Republic of China Bamboo Research Institute Nanjing Forestry UniversityNanjing 210037People’s Republic of China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium Institute of Agricultural and Environmental Sciences Estonian University of Life Sciences51006 TartuEstonia Estonian Academy of Sciences 10130 TallinnEstonia Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia Biodiversity Macroecology and BiogeographyUniversity of Göttingen37077 GöttingenGermany

The shape of leaf laminae exhibits considerable diversity and complexity that reflects adaptations to environmental factors such as ambient light and precipitation as well as phyletic *** leaves appear to be elliptical which may represent a‘default’developmental ***,whether their geometry truly conforms to the ellipse equation(EE),i.e.,(x/a)^(2)+(y/b)^(2)=1,remains *** alternative is described by the superellipse equation(SE),a generalized version of EE,i.e.,|x/a|^(n)+|y/b|^(n)=*** test the efficacy of EE versus SE to describe leaf geometry,the leaf shapes of two Michelia species(i.e.,*** ***,and ***),were investigated using 60 leaves from each *** shows that the majority of leaves(118 out of 120)had adjusted root-mean-square errors of<0.05 for the nonlinear fitting of SE to leaf geometry,i.e.,the mean absolute deviation from the polar point to leaf marginal points was smaller than 5%of the radius of a hypothesized circle with its area equaling leaf *** estimates of n for the two species were<2,indicating that all sampled leaves conformed to SE and not to *** study confirms the existence of SE in leaves,linking this to its potential functional advantages,particularly the possible influence of leaf shape on hydraulic conductance.

关键词： Bilateral symmetry Leaf ellipticalness index Leaf laminae Leaf roundness index Magnoliaceae