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From the dust:extracellular vesicles as regulators of development and neuroregeneration

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Neural Regeneration Research 2024年第5期19卷 933-934页

作者： Leon g.Coleman Jr The University of North Carolina at Chapel hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

First impressions can have a lasting *** science,this can be especially problematic,because our lack of understanding often causes us to mislabel and thus ignore important biological *** this vein,extracellular vesicles(EVs)were once considered to be“cellular dust”.Similar to the previous concept of“junk DNA”to describe protein non-coding regions,EVs are far more than just cellular *** fact,EVs are emerging as key mediators of intracellular communication across nearly all biological *** includes peripheral immune responses(e.g.,arthropathies and sepsis),intra-organ communication(Seim et al.,2023),and a host of other physiological and pathological states(Figure 1A and b).

关键词： Figure extracellular

genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin:Creation of an unnatural analogue with improved anticancer properties

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Acta Pharmaceutica Sinica b 2024年第1期14卷 421-432页

作者： Dexiu Yan Jemma Arakelyan Teng Wan Ritvik Raina Tsz Ki Chan Dohyun Ahn Vladimir Kushnarev Tsz Kiu Cheung Ho Ching Chan Inseo Choi Pui Yi Ho Feijun Hu Yujeong Kim hill Lam Lau Ying Lo Law Chi Seng Leung Chun Yin Tong Kai Kap Wong Wing Lam Yim Nikolay S.Karnaukhov Richard Y.C.Kong Maria V.babak Yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina igEM Team“VarieCure” City University of Hong KongHong Kong SARChina Department of biomedical Engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.S.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin(1)and variecolactone(2)was identified in Aspergillus aculeatus ATCC *** production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 ***,the replacement of Vrcb with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues(5-7).Analysis of the compounds’anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic *** study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

关键词： Animal studies Anticancer properties biosynthesis Natural products Sesterterpenoids Synthetic biology Terpene synthases Variecolin

Electrically pumped metallic and plasmonic nanolasers

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Chinese Physics b 2018年第11期27卷 158-166页

作者： Martin T hill School of Electrical Electronic and Computer Engineering The University of Western Australia

In recent years, there have been a significant number of demonstrations of small metallic and plasmonic lasers. The vast majority of these demonstrations have been for optically pumped devices. Electrically pumped devices are advantageous for applications and could demonstrate concepts not amenable for optical pumping. However, there have been relatively few demonstrations of electrically pumped small metal cavity lasers. This lack of results is due to the following reasons： there are limited types of electrically pumped gain media available; there is a significantly greater level of complexity required in the fabrication of electrically pumped devices; finally, the required components for electrical pumping restrict cavity design options and furthermore make it intrinsically more difficult to achieve lasing. This review looks at the motivation for electrically pumped nanolasers, the key issues that need addressing for them to be realized, the results that have been achieved so far including devices where lasing has not been achieved, and potential new directions that could be pursued.

关键词： semiconductor lasers laser diode microcavity and microdisk laser integrated optics

Characterization of Ion Contents and Metabolic Responses to Salt Stress of Different Arabidopsis AtHKT1;1 genotypes and Their Parental Strains

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Molecular Plant 2013年第2期6卷 350-368页

作者： Camilla b. hill Deepa Jha Antony bacic Mark Tester Ute Roessner Australian Centre for Plant Functional genomics School of Botany University of Melbourne Victoria 3010 Australia Australian Centre for Plant Functional genomics University of Adelaide Waite Campus Glen Osmond 5064 SA Australia Metabolomics Australia School of Botany University of Melbourne Victoria 3010 Australia bio21 Molecular Science and biotechnology Institute University of Melbourne Victoria 3010 Australia ARC Centre of Excellence in Plant Cell Walls School of Botany University of Melbourne Victoria 3010 Australia

Plants employ several strategies to maintain cellular ion homeostasis under salinity stress, including mediat-ing ion fluxes by transmembrane transport proteins and adjusting osmotic pressure by accumulating osmolytes. The HKT （high-affinity potassium transporter） gene family comprises Na^＋ and Na^＋/K^＋ transporters in diverse plant species, with HKT1,1 as the only member in Arabidopsis thaliana. Cell-type-specific overexpression of AtHKT1;1 has been shown to prevent shoot Na^＋ overaccumulation under salinity stress. Here, we analyzed a broad range of metabolites and elements in shoots and roots of different AtHKT1;1 genotypes and their parental strains before and after salinity stress, revealing a reciprocal relationship of metabolite differences between an AtHKT1;1 knockout line （hktl;1） and the AtHKT1;1 overex- pressing lines （E2586 UASgAL4：HKT1;1 and J2731＊UASgAL4：HKT1;1）. Although levels of root sugars were increased after salt stress in both AtHKTI,1 overexpressing lines, E2586 UASgAL4：HKT1;1 showed higher accumulation of the osmopro-tectants trehalose, gentiobiose, and melibiose, whereas J2731＊UASgAL4：HKT1;1 showed higher levels of sucrose and raffinose, compared with their parental lines, respectively. In contrast, the knockout line hktl,1 showed strong increases in the levels of the tricarboxylic acid （TCA） cycle intermediates in the shoots after salt treatment. This coincided with a significant depletion of sugars, suggesting that there is an increased rate of carbon influx into the TCA cycle at a constant rate of C-efflux from the cycle, which might be needed to support plant survival during salt stress. Using correlation analysis, we identified associations between the Na^＋ content and several sugars, suggesting that regulation of sugar metabolism is important in plant responses to salinity stress.

关键词： abiotic stress salinity salt tolerance HKT sodium transporter, metabolomics enhancer trap system.

Soybean aphid intrabiotype variability based on colonization of specific soybean genotypes

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Insect Science 2015年第6期22卷 785-792页

作者： Michelle Pawlowski Curtis b. hill David J. Voegtlin glen L. Hartman Department of Crop Sciences National Soybean Research Center University of Illinois Urbana Illinois USA Center for EconomicEntomology Illinois Natural History Survey University of Illinois Champaign Illinois USA USDA Agricultural Research Service National Soybean Research Center University of Illinois Urbana Illinois USA

The soybean aphid, Aphis glycines Matsumura （Hemiptera： Aphididae）, is one of the most destructive insect pests on soybeans in the United States. One method for managing this pest is through host plant resistance. Since its arrival in 2000, 4 aphid biotypes have been identified that are able to overcome soybean aphid resistance （Rag） genes. A soybean aphid isolate collected from Moline, Illinois readily colonized soybean plants with the soybean aphid resistance gene Rag2, unlike biotypes 1 and 2, but similar to soybean aphid biotype 3. Two no-choice experiments compared the virulence of the Moline isolate with biotype 3. In both experiments, differences in aphid population counts were not significant （P 〉 0.05） on soybean genotypes LD08-12957a （Rag2） and LD11-5413a （Rag2）, but the aphid counts for the Moline isolate were significantly （P 〈 0.05） lower than the aphid counts for the biotype 3 isolate on the soybean genotypes Dowling （Rag1）, LD05-16611 （Rag1）, LD11-4576a （Rag1）, and P1567598b （raglb and rag3）. The Moline isolate was a variant of aphid biotype 3, which is the first report showing that soybean aphid isolates classified as the same biotype, based on virulence against specific Rag genes, can differ in aggressiveness or ability to colonize specific host genotypes.

关键词： Aphis glycines biotype biotype variant soybean soybean aphid resistance

Assessing stakeholders'perceptions and values towards social-ecological systems using participatory methods

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Ecological Processes 2014年第1期3卷 31-42页

作者： grace b Villamor Ignacio Palomo Cesar A Lopez Santiago Elisa Oteros-Rozas Joe hill Department of Ecology and Natural Resources Management Center for Development Research(ZEF)University of Bonn53113BonnGermany World Agroforestry Centre(ICRAF) Jl.Situ Gede16115 BogorIndonesia basque Centre for Climate Change(bC3) Alameda Urquijo 448008 BilbaoSpain Department of Ecology Social-Ecological Systems LaboratoryUniversidad Autónoma de MadridMadrid 28049Spain Department of Political and Cultural Change Center for Development Research(ZEF)University of Bonn53113 BonnGermany

Introduction:Many conservation initiatives for managing social-ecological landscapes factor in the best available biophysical ***,insufficient consideration of social aspects can render such initiatives *** incorporating stakeholders'perceptions and values,and by involving stakeholders(transparently)in decision-making processes,conservation plans and efforts can better achieve desired goals and ***:In this paper,we present and analyze three case studies within different ecological and land use *** case study uses different participatory approaches to elicit stakeholders'perceptions and values,while seeking to involve stakeholders in the decision-making *** case studies are the following:(1)participatory scenario planning for a protected area in Doñana coastal wetland in Southwestern Spain;(2)assessment of ecosystem services trade-offs and social responses on rewards for agro-biodiversity in the rubber agroforest landscape in Jambi,Indonesia;and(3)socio-cultural evaluation,through visual stimuli,of ecosystem services provided by transhumance cultural landscapes in Central *** discuss how stakeholders perceive and value their environments and to what extent participatory approaches are useful for capturing information relating to land use and ecological ***:Social-ecological systems are inherently complex,having a variety of interacting actors with different types of ecological knowledge,interests,and *** participatory tools or approaches are appropriate for various and specific contexts and *** and integrating the various types of knowledge and values of different actors can contribute to a more comprehensive understanding of social-ecological systems.

关键词： Actors Ecosystem services Ecological knowledge Social processes Socio-cultural valuation Values

A simple umbelliferone based fluorescent probe for the detection of nitroreductase

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Frontiers of Chemical Science and Engineering 2018年第2期12卷 311-314页

作者： Adam C. Sedgwick Alex Hayden barry hill Steven D. bull Robert b. P. Elmes Tony D. James Department of Chemistry University of Bath Bath BA2 7AY UK Department of Chemistry Maynooth University Maynooth Co. Kildare Ireland

A simple nitrobenzyl-umbelliferone （NCOU1） was synthesised containing a nitroreductase （NTR） trigger moiety. The presence of NTR, resulted in the fragmentation of the parent molecule and release of the highly emissive fluorophore umbelliferone via an NTR-catalyzed reduction of the nitro group. In the presence of the NTR enzyme, NCOU1 gave rise to a 5-fold increase in fluorescence intensity at 455 nm and was selective for NTR over other reductive enzymes. These results indicate that NCOU1 can be used as a simple assay for the detection of NTR.

关键词： NITRO RADICALS NTSR1 gene FLUORESCENT PRObES Skimmetin Nitroreductases noise-temperature ratio

Molecular rotor based on an oxidized resorcinarene

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Organic Chemistry Frontiers 2022年第1期9卷 39-50页

作者： Daniel T.Payne Jan Labuta Zdeněk Futera Václav březina Lenka Hanyková Mandeep K.Chahal Jonathan P.hill International Center for Materials Nanoarchitectonics National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan bInternational Center for Young Scientists National Institute for Materials ScienceNamiki 1-1TsukubaIbaraki 305-0044Japan Institute of Physics Faculty of ScienceUniversity of South BohemiaBranišovská1760ČeskéBudějovice 37005Czech Republic Faculty of Mathematics and Physics Charles UniversityV Holešovičkách 218000 Prague 8Czech Republic

Molecular rotors are an important class of dynamic molecules which have been studied not only for their possible uses as components of molecular machines but also because of potential applications as probes of local viscosity in biological media,especially self-assembled *** the former,factors affecting rotational motility are critical while for the latter the rotor activity must be complexed with an output signal(often fluorescence)for reporting of local *** single stator-double rotor activity of an oxidized resorcinarene(fuchsonarene)macrocycle containing unsaturated hemiquinonoid groups at its meso positions was *** contain two hemiquinonoid substituents at diagonally-opposed meso-positions with two electron rich phenol groups at the remaining meso-positions between the hemiquinonoid *** meso-substituents are in proximity at one side of the resorcinarene macrocycle(so-called rccc-type isomer)with rotational activity of the phenol *** rates of the phenol moieties can be controlled by varying temperature,solvent polarity and acidity of the medium of study with rotation being thermally activated in neutral and acidic media and tunable in the range from 2 s^(−1) to 20000 s^(−1).Experimental and computational data indicate that rotation of the mobile phenol meso-substituents is remotely affected by interactions with acidic solvents at the carbonyl CvO groups of macrocyclic acetyloxy groups,which occurs with the emergence of a lower energy electronic absorption band whose intensity is correlated with both the acidity of the medium and the rotation rate of the phenol ***-dependent DFT calculations suggest that the low energy band is due to a molecular conformational adjustment affecting electronic conjugation caused by strong interaction of macrocyclic acetyloxy carbonyl groups with the acid *** work presents a molecular mechanical model for estimating solution acidity a

关键词： substituent rotation oxidized

Exploring ancestral phenotypes and evolutionary development of the mammalian middle ear based on Early Cretaceous Jehol mammals

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National Science Review 2021年第5期8卷 57-66页

作者： Fangyuan Mao Cunyu Liu Morgan hill Chase Andrew K.Smith Jin Meng Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment Division of Paleontology American Museum of Natural History beipiao Pterosaur Museum of China 5. Microscopy and Imaging Facility American Museum of Natural History Earth and Environmental Sciences Graduate CenterCity University of New York

We report a new Cretaceous multituberculate mammal with 3 D auditory bones preserved. Along with other fossil and extant mammals, the unequivocal auditory bones display features potentially representing ancestral phenotypes of the mammalian middle ear. These phenotypes show that the ectotympanic and the malleus-incus complex changed notably during their retreating from the dentary at various evolutionary stages and suggest convergent evolution of some features to extant mammals. In contrast, the incudomalleolar joint was conservative in having a braced hinge configuration, which narrows the morphological gap between the quadroarticular jaw joint of non-mammalian cynodonts and the incudomalleolar articulations of extant mammals. The saddle-shaped and abutting malleus-incus complexes in therians and monotremes, respectively, could have evolved from the braced hinge joint *** evolutionary changes recorded in the Mesozoic mammals are largely consistent with the middle ear morphogenesis during the ontogeny of extant mammals, supporting the relation between evolution and development.

关键词： Cretaceous Jehol biota malleus-incus ectotympanic mammal evolution