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Petiveria alliacea Suppresses Airway Inflammation and Allergen-Specific Th2 Responses in Ovalbumin-Sensitized Murine Model of Asthma

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Chinese Journal of Integrative Medicine 2018年第12期24卷 912-919页

作者： Rosa martha Perez Gutierrez Jose Maria Mota Flores Natural Products Research Laboratory Higher School of Chemical Engineering and Extractive IndustriesInstituto Politecnico Nacional (IPN) Professional Unit Adolfo Lopez Mateos Av. Instituto Politécnico NacionalS/N

Objective： To examine the effect of metanol extract of Petiveria alliacea （PM） on airway inflammation in a murine model of chronic asthma. Methods： Two-month-old male BALB/c mice （n=6-8/group） were sensitized on days 0 and 14 by intraperitoneal injection of 20μg ovalbumin （OVA）. On day 25, the mice received an airway challenge with OVA （3%, w/v, in phosphate buffered saline）. PM was administered orally by oral gavage to mice at doses of 100, 200 and 400 mg/kg body weight once daily from days 18 to 23. Control mice were orally administered phosphate buffered saline （PBS） to induce a model of asthma. At the end of the test, respiratory reactivity was assayed, the total cell number, interleukin-4 （IL-4）, IL-5, IL-13, tumor necrosis factor-alpha （TNF-α） and reactive oxygen species （ROS） in the bronchoalveolar lavage fluid （BALF） were determined and the levels of serum IgE, intercellular cell adhesion molecule 1 （ICAM-1） and eotoxin were measured. In addition, lung tissue was used to qualify the IL-4, IL-5, IL-13, TNF-α and transforming growth factor beta 1 （TGF-β1）. Histologic examination was performed to observe inflammatory cellular infiltration. Results： The administration of PM in comparison with the OVA-only treated group significantly attenuated the infiltration of eosinophUs and other inflammatory cells （P〈0.01）. Airway resistance （RI） in the OVA-only induced group was significantly higher than that of the PBS control group （P〈0.01） when methacholine was added. TNF-α, IgE, TGF-β1 and cytokine levels IL-4, IL-5, IL-β in the BALF decreased compared to control mice （P〈0.01 or P〈0.05）. PM treatment also inhibited the production of chemokines, eotaxin and ICAM-1 in BALF （P〈0.01）, which improved lung function. Histopathological examination revealed that the sensitized treated PM groups had significant lower in inflammatory scores similar to dexamethasone treatments and the untreated group. Conclusion： Administration of PM could inhibit airway inflammation, regulate cyt

关键词： Petiveria alliacea allergy antiinflammation asthma

Calcineurin B-like interacting protein kinase OsCIPK23 functions in pollination and drought stress responses in rice (Oryza sativa L.)

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Journal of Genetics and Genomics 2008年第9期35卷 531-543页

作者： Wenqiang Yang Zhaosheng Kong edith Omo-Ikerodah Wenying Xu Qun Li Yongbiao Xue Institute of Genetics and Developmental Biology Chinese Academy of Sciences National Centre for Plant Gene Research Beijing 100190 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Drought is very harmful to grain yield due to its adverse effect on reproduction, especially on pollination process in rice. However, the molecular basis of such an effect still remains largely unknown. Here, we report the role of a member of CBL （Calcineurin B-Like） Interacting Protein Kinase （CIPK） family, OsCIPK23, in pollination and stress responses in rice. Molecular analyses revealed that it is mainly expressed in pistil and anther but up-regulated by pollination, as well as by treatments of various abiotic stresses and phytohormones. RNA interference-mediated suppression of OsCIPK23 expression significantly reduced seed set and conferred a hypersensitive response to drought stress, indicating its possible roles in pollination and drought stress. In consistent, overexpression of OsCIPK23 induced the expression of several drought tolerance related genes. Taken together, these results indicate that OsCIPK23 is a multistress induced gene and likely mediates a signaling pathway commonly shared by both pollination and drought stress responses in rice.

关键词： OsCIPK23 water pollination drought rice (Oryza sativa L.)

The functional role of miRNAs in colorectal cancer: insights from a large population-based study

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Cancer Biology & Medicine 2019年第2期16卷 211-219页

作者： Lila E.Mullany martha L.Slattery Department of Internal Medicine University of Utah

Identification of causal microRNAs(miRNAs) in colorectal cancer(CRC) is elusive, due to our lack of understanding of how specific miRNAs affect biological pathways and outcomes. An miRNA can regulate many mRNAs and an mRNA can be associated with many miRNAs;appreciation of these complex networks in which miRNAs operate is necessary to transition from identifying dysregulated miRNAs to identifying individual miRNAs or groups of miRNAs that are suitable for therapeutic purposes. The aim of the paper is to compile results from a population-based study(n = 1,954 cases with matched carcinoma/normal tissue) of miRNAs in CRC. The information gained allows for cohesive and comprehensive insight into miRNAs and CRC in terms of function and impact. Comparison of miRNA expression with mRNA expression from nine signaling pathways in carcinogenic processes allowed us to identify miRNA targets within a biological context. MiRNAs that directly influence mRNA expression may be effective biomarkers or therapeutic targets.

关键词： mRNA miRNA pathways colorectal cancer

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准则、规划和保护:在莫高窟的保护合作

敦煌研究 2024年第4期 18-29页

作者：内维尔·阿根纽玛莎·迪马斯莎伦·莎莉文王平先(译) 盖蒂保护研究所美国洛杉矶90001 澳大利亚遗产委员会澳大利亚堪培拉0200 敦煌研究院编辑部甘肃兰州730030

在中国国家文物局的支持下,敦煌研究院和盖蒂保护研究所已经在莫高窟和其他历史文化遗址有效地协同合作了约35年。在这些年中,双方开展了很多项目和活动。所有活动的指导原则都是通过保护干预、规划和管理、培训、研究和制定广泛适用的... 详细信息

在中国国家文物局的支持下,敦煌研究院和盖蒂保护研究所已经在莫高窟和其他历史文化遗址有效地协同合作了约35年。在这些年中,双方开展了很多项目和活动。所有活动的指导原则都是通过保护干预、规划和管理、培训、研究和制定广泛适用的方法来保护遗址的诸多价值。

关键词：莫高窟敦煌研究院盖蒂保护研究所文物保护合作

Using Location based Augmented Reality to Improve Destination Image of China-Beijing:Role of Immersive Experience,User Engagement,Perceived Service Quality and Authenticity

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Using Location based Augmented Reality to Improve Destinatio...

作者： Vikih edith Vefemsi 山西大学

学位级别：硕士

旅游业正蓬勃发展,过去七年中全球旅游业保持持续增长。中国旅游业现已发展成为国内经济最重要的支柱产业之一。“旅游目的地形象”这一概念表示游客对特定目的地的综合感知和印象。如今,人们认为良好的旅游目的地形象是带动旅游业发展... 详细信息

旅游业正蓬勃发展,过去七年中全球旅游业保持持续增长。中国旅游业现已发展成为国内经济最重要的支柱产业之一。“旅游目的地形象”这一概念表示游客对特定目的地的综合感知和印象。如今,人们认为良好的旅游目的地形象是带动旅游业发展的重要因素。因此,在旅游业中,旅游目的地形象和沉浸式体验这两个概念获得广泛关注。本研究运用实证主义哲学,基于演绎方法的定量研究,旨在探讨通过提升沉浸体验给旅游目的地形象所带来的影响,并分析通过提升游客的实际用户体验、感知服务质量和感知真实性给旅游目的地形象所带来的间接影响。本研究针对422位旅客通过在线问卷调查的方式收集了与上述变量相关的数据,所有旅客均为到访北京并在旅行期间使用基于地理位置的增强现实技术（LBAR）的人。样本采集针对性强,采样技术便捷。分析结果表明,提升旅客的沉浸式体验不仅对旅游目的地形象影响显著,而且对于旅客的用户体验、感知服务质量和感知真实性给旅游目的地形象所带来的间接影响,影响也较为显著。基于SEM假设检验,证实本研究中提出的所有假设都是正确的。故本研究对于未来旅游业发展以及增强现实技术在旅游业中的应用具有重要意义。

关键词：增强现实技术沉浸式体验旅游目的地形象用户体验感知服务质量感知真实性

Memory for location and visual cues in white-eared hummingbirds Hylocharis leucotis

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Current Zoology 2011年第4期57卷 468-476页

作者： Guillermo PEREZ Carlos LARA Jose VICCON-PALE martha SIGNORET-POILLON Doctorado en Ciencias Biologicas Universidad Autonoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 Moxico D.F. Moxico Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtoncatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Moxico. Departamento el Hombre y su Ambiente. Universidad Autdnoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 MExico D.F. Mexico

In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 （4）： 468-476, 2011].

关键词： Visual cues Location White-eared hummingbird Foraging

Rare earth element geochemistry in soils along arid and semiarid grasslands in northern China

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Ecological Processes 2022年第1期11卷 386-399页

作者： Yi‑Wen Cao Xiao‑Ming Liu Chao Wang edith Bai Nanping Wu CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China Department of Earth Marine and Environmental SciencesUniversity of North Carolina‑Chapel HillChapel HillNC 27515USA Key Laboratory of Geographical Processes and Ecological Security of Changbai Mountains School of Geographical SciencesNortheast Normal UniversityChangchun 130024China Institute of Deep‑Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Background:Rare earth elements(REE)are a group of trace elements that behave geochemically *** fractionation patterns normalized to reference materials provide a powerful tool for documenting *** processes are particularly difficult to illustrate with respect to contemporary and past climate *** this study,we characterize the rare earth element(REE)contents in bulk soils and respective geochemical fractions(e.g.,exchangeable,carbonate‑bound,reducible,and oxidizable fractions)and to decipher the relationships between REE geochemistry components and climatic factors across a large‑scale northern China transect(NCT).Results:Across the NCT,bulk REE concentrations ranged from 55.2 to 241.1μg g^(−1)with a main portion in the residual fraction(49–79%),followed by oxidizable fraction(2–40%),reducible fraction(3–22%),carbonate‑bound fraction(0.1–16%),and negligible exchangeable *** REE contents of geochemical components(carbonate‑bound,reducible,and oxidizable)in topsoils correlated to climate factors(mean annual precipitation,mean annual temperature,potential evaporation,and aridity index(AI)).The normalized abundances to the upper continental crust(UCC)composition show that the middle REE was generally enriched than the light REE and heavy REE in topsoils along the *** overall UCC‑normalized bulk REE patterns in topsoils and subsoils were similar,characterized by weak negative Ce anomalies and positive Eu ***:Our data in topsoils and depth profiles collectively suggest that cycling of REE was primarily regulated by abiotic processes in area with AI*** similar UCC normalized patterns in topsoils suggest that the REE was originated from a common source with limited influences from other sources(e.g.,atmospheric dusts and anthropogenic contribu‑tions).Our results to some extent provide evidence for

关键词： Rare earth elements Soil Grassland Northern China Aridity index

Fiber transmission demonstrations in vector mode space division multiplexing

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Frontiers of Optoelectronics 2018年第2期11卷 155-162页

作者： Leslie A. rusch Sophie LAROCHELLE Centre for Optics Photonics and Lasers ECE Department Universite Laval Quebec G1V 0A6 Canada

Much attention has been focused on the use of scalar modes for space division multiplexing （SDM）. Alternative vector mode bases offer another solution set for SDM, expanding the available trade-offs in system performance and complexity. We present two types of ring core fiber conceived and designed to explore SDM with fibers exhibiting low interactions between supported modes. We review demonstrations of fiber data transmis- sion tbr two separate vector mode bases： one for orbital angular momentum （OAM） modes and one for linearly polarized vector （LPV） modes. The OAM mode demon- strations include short transmissions using commercially available transceivers, as well as kilometer length transmission at extended data rates. The LPV demonstra- tions span kilometer length transmissions at high data rate with coherent detection, as well as a radio over fiber experiment with direct detection of narrowband signals.

关键词： space division multiplexing (SDM) few-mode fiber (FMF) orbital angular momentum (OAM) linearly polarized vector (LPV) modes ring core fiber(RCF) polarization maintaining fiber

Reaction mechanism of azoreductases suggests convergent evolution with quinone oxidoreductases

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Protein & Cell 2010年第8期1卷 780-790页

作者： Ali Ryan Chan-Ju Wang Nicola Laurieri Isaac Westwood edith Sim Department of Pharmacology University of OxfordMansfield RoadOxfordOX13QTUK

Azoreductases are involved in the bioremediation by bacteria of azo dyes found in waste *** the gut flora,they activate azo pro-drugs,which are used for treatment of inflammatory bowel disease,releasing the active component 5-aminosalycilic *** bacterium *** has three azoreductase genes,paAzoR1,paAzoR2 and paAzoR3,which as recombinant enzymes have been shown to have different substrate *** mechanism of azoreduction relies upon tautomerisation of the substrate to the hydrazone *** report here the characterization of the *** azoreductase enzymes,including determining their thermostability,cofactor preference and kinetic constants against a range of their favoured *** expression levels of these enzymes during growth of *** are altered by the presence of azo *** is shown that enzymes that were originally described as azoreductases,are likely to act as NADH quinone *** low sequence identities observed among NAD(P)H quinone oxidoreductase and azoreductase enzymes suggests convergent evolution.

关键词： azoreductase enzyme mechanism NAD(P)H quinone oxidoreductase enzyme characterisation convergent evolution