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Fractionation and characterization of polysaccharides from cyanobacterium Spirulina (Arthrospira) maxima in nitrogen-limited batch culture

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journal of Central South University of Technology 2002年第2期9卷 81-86页

作者：聂珍媛夏金兰 j.M.LEVERT Institute of Bioengineering Faculty of Resource Processing and Bioengineering Central South University Changsha 410083 China Service de Chimie et Biochimie Appliquées Faculté Polytechnique de Mons Mons 7000 Belgque

By a sequentially selective extraction procedure, polysaccharides (ps) from cyanobacterium Spirulina (Arthrospira) maxima that can be bio functionally healthy components were fractionated in four parts including the culture medium (psCM), the external layers of the cell (psEL), the cell wall (psCW) and storage granules (psSG). The four fractionated parts of polysaccharides were characterized by gas liquid chromatography (GLC) equipped with FID and fused silica capillary column (15 m×0.53 mm i. d.). The contents of psCM, psEL, psCW and psSG were about 2.0%, 2.6%, 10.0% and 52.0% to cell dry matter, respectively. Glucose was almost the only monosaccharide in psSG and psCW and most predominant in psEL, while in psCM, xylose, rhamnose and glucose were the main ones. Two uronic acids represented by glucuronic acid and galacturoic acid, six neutral monosaccharides including fucose, rhamnose, xylose, mannose, galactose and glucose, and two possible unidentified sugars were found in psEL and psCM. These data are valuable for the selective productions of high added value sugars from Spirulina .

关键词： characterization cyanobacterium extraction fractionation gas liquid chromatography polysaccharides Spirulina (Arthrospira) maxima

Surfactant protein A (SP-A) binds to phosphatidylserine and competes with annexin V binding on late apoptotic cells

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Protein & Cell 2010年第2期1卷 188-197页

作者： Anne jäkel Kenneth B.M.Reid Howard Clark Department of Pharmacology University of OxfordMansfield RoadOxford OX13QTUK MRC Immunochemistry Unit Department of BiochemistryUniversity of OxfordSouth Parks RoadOxford OX13QUUK University of Southampton MP 803 Level FSouth BlockSouthampton General HospitalSouthampton SO166YDUK

The role of surfactant protein A(SP-A)in the recognition and clearance of apoptotic cells is well established,but to date,it is still not clear which surface molecules of apoptotic cells are involved in the *** we present evidence that phosphatidylserine(ps)is a relevant binding molecule for human *** binding is Ca^(2+)-dependent and is not inhibited by mannose,suggesting that the sugar-binding site of the carbohydrate recognition domain(CRD)of SP-A is not *** cytometry studies on apoptotic jurkat cells revealed apparent inhibition of annexin V binding by increasing concentrations of SP-A in late apoptotic but not early apoptotic cells,and this was consistent for jurkat cells and *** these data,confocal microscopy results show a co-localisation of annexin V and SP-A in late apoptotic but not early apoptotic ***,we cannot conclude that this inhibition is exclusively due to the binding of SP-A to ps on the cell surface,as annexin V is not wholly specific for ps and SP-A also interacts with other phospholipids that might become exposed on the apoptotic cell surface.

关键词： surfactant proteins phosphatidylserine apoptotic cells

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一般人群中腹型肥胖和新发心房颤动的关系

中华高血压杂志 2017年第9期25卷 830-830页

作者：刘莉叶鹏 Baek YS Yang ps Kim TH Uhm jS Park j Pak HN Lee MH joung B

已知身高越高,体质量越大,心房颤动发生风险越高。然而,心房颤动的风险是否与腹型肥胖有关尚不清楚。Baek等纳入韩国国民健康保险计划全国样本队列中基线无心房颤动的成人501 690人,年龄（47.6±14.3）岁,女性250 664人,占50%。测定其... 详细信息

已知身高越高,体质量越大,心房颤动发生风险越高。然而,心房颤动的风险是否与腹型肥胖有关尚不清楚。Baek等纳入韩国国民健康保险计划全国样本队列中基线无心房颤动的成人501 690人,年龄（47.6±14.3）岁,女性250 664人,占50%。测定其体质量指数（body mass index,BMI）和腰围,将BMI〈18．5kg／m2定义为低体质量，18．5～〈25．0kg／m2定义为正常体质量；25．0～〈30．0kg／m2定义为超重；≥30．0kg／m2定义为肥胖；将腰围≥90（男性）和≥80cm（女性）定义为腹型肥胖。

关键词：心房颤动腹型肥胖体质量保险计划国民健康基线队列腰围样本 body

Comparative study of 2mol% Li- and Mn-substituted lead-free potassium sodium niobate ceramics

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International journal of Minerals,Metallurgy and Materials 2014年第12期21卷 1241-1246页

作者： Asha Dahiya O.P.Thakur j.K.juneja Sangeeta Singh Dipti School of Applied Sciences Netaji Subhas Institute of Technology Dwarka University of Delhi Department of Physics Hindu College Department of Physics Geeta Vidya Mandir Girls College School of Physics & Material Sciences Thapar University

The effect of Li and Mn substitution on the dielectric, ferroelectric and piezoelectric properties of lead free K0.5Na0.5NbO3 （KNN） was investigated. Samples were prepared using a conventional solid state reaction method. The sintefing temperature for all the samples was 1050℃. The optimum doping concentration for the enhancement of different properties without the introduction of any other co-dopants such as Ti, Sb, and La was investigated. X-ray diffraction analysis confirmed that all the samples crystallize in a single phase perovskite structure. The dielectric properties were investigated as a function of temperature and applied electric field frequency. Compared with Li-substituted KNN （KLNN）, Mn-substituted KNN （KMNN） exhibited a higher dielectric constant εmax （i.e., 4840） at its critical transition temperature Tc （i.e., 421℃） along with a lower value of tangent loss at 10 kHz and greater values of saturation polarisation ps （i.e., 20.14 μC/cm^2） and remnant polarisation Pr （i.e., 15.48 μC/cm^2）. The piezoelectric constant （d33） of KMNN was 178 pC/N, which is comparable to that of lead-based hard ceramics. The results presented herein suggest that B-site or Mn substitution at the optimum concentration results in good enhancement of different properties required for materials used in memory devices and other applications.

关键词： ceramics dielectric properties ferroelectricity piezoelectricity substitution comparative study

Mutated trimeric RBD vaccines:a platform against variants of concern

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Signal Transduction and Targeted Therapy 2023年第5期8卷 2038-2040页

作者： Belén Aparicio juan j.Lasarte Pablo Sarobe Programa de Inmunología e Inmunoterapia Centro de Investigación Médica Aplicada(CIMACCUN)Universidad de NavarraPamplona31008Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas(CIBEREHD) Pamplona31008Spain IdiSNA Instituto de Investigación Sanitaria de NavarraPamplona31008Spain

He et *** reported in Nature Communications1 the development of a protein vaccine against SASR-CoV-2 Omicron variant consisting of a trimer of the spike protein receptor-binding domain(RBD)of the Delta variant fused to heptad-repeat sequences 1 and *** vaccine induced broad-spectrum neutralizing antibodies and fully protected mice and non-human primates against challenge with live Delta and Omicron virus.

关键词： vaccine vaccines

Themis regulates metabolic signaling and effector functions in CD4^(+) T cells by controlling NFAT nuclear translocation

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Cellular & Molecular Immunology 2021年第9期18卷 2249-2261页

作者： Mukul Prasad joanna Brzostek Namrata Gautam Renu Balyan Vasily Rybakin Nicholas R.j.Gascoigne Translational Immunology Programme Yong Loo Lin School of MedicineNational University of Singapore5 Science Drive 2Singapore 117545Singapore Department of Microbiology and Immunology Yong Loo Lin School of MedicineNational University of Singapore5 Science Drive 2Singapore 117545Singapore H.Lee Moffitt Cancer Center and Research Institute TampaFLUSA Torque Therapeutics CambridgeMAUSA

Themis is a T cell lineage-specific molecule that is involved in TCR signal *** effects of germline Themis deletion on peripheral CD4^(+)T cell function have not been described *** this study,we found that Themis-deficient CD4^(+)T cells had poor proliferative responses,reduced cytokine production in vitro and weaker inflammatory potential,as measured by their ability to cause colitis in *** T cells are quiescent,whereas activated T cells have high metabolic *** of these metabolic demands depends upon nutrient availability and upregulation of nutrient intake channels after efficient TCR signal transduction,which leads to metabolic reprogramming in T *** tested whether defects in effector functions were caused by impaired metabolic shifts in Themis-deficient CD4^(+)T cells due to inefficient TCR signal transduction,in turn caused by the lack of *** found that upon TCR stimulation,Themis-deficient CD4^(+)T cells were unable to upregulate the expression of insulin receptor(IR),glucose transporter(GLUT1),the neutral amino acid transporter CD98 and the mTOR pathway,as measured by c-Myc and ps6 *** analysis of activated Themis-deficient CD4^(+)T cells showed more oxidative phosphorylation(OXPHOS)than aerobic glycolysis,indicating defective metabolic ***,we found reduced NFAT translocation in Themis-deficient CD4^(+)T cells upon TCR *** previously reported ChIP-seq and RNA-seq data,we found that NFAT nuclear translocation controls IR gene ***,our results describe an internal circuit between TCR signal transduction,NFAT nuclear translocation,and metabolic signaling in CD4^(+)T cells.

关键词： Immunometabolism NFAT nuclear translocation Insulin receptor mTOR Mitochondria

The Epsps Pro106Ser substitution solely accounts for glyphosate resistance in a goosegrass(Eleusine indica) population from Tennessee, United States

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journal of Integrative Agriculture 2016年第6期15卷 1304-1312页

作者： janel L Huffman Chance W Riggins Lawrence E Steckel Patrick j Tranel Department of Crop Sciences University of Illinois Urbana IL 61801 USA Department of Plant Sciences University of Tennessee Jackson TN 38301 USA

Previous studies have documented the occurrence of glyphosate-resistant （GR） goosegrass （Eleusine indica （L.） Gaertn.） and, in at least some cases, resistance is due to an altered target site. Research was performed to determine if an altered target site was responsible for GR in a Tennessee, United States goosegrass population （TennGR）. DNA sequencing revealed a mutation in TennGR plants conferring the Prol06Ser 5-enolpyruvylshikimate-3-phosphate synthase （Epsps） substitution previously identified in other GR populations. F2 populations were derived from TennGR plants crossed with plants from a glyphosate-susceptible population （TennGS） and analyzed for their response to glyphosate and genotyped at the Epsps locus. Plants from the F2 populations segregated 1：2：1 sensitive：intermediate：resistant in response to a selec- tive dose of glyphosate, and these responses co-segregated with the Epsps genotypes （PP106, ps106, and SS106）. To separately investigate the effect of the Prol06Ser substitution on GR, glyphosate dose-response curves and 50% effective dose （EDso） values were compared among the three genotypes and the two parental populations. The SS106 genotype was 3.4-fold resistant relative to the PP106 genotype, identical to the resistance level obtained when comparing the resistant and susceptible parental populations. We conclude that the mutation conferring a Prol06Ser Epsps mutation is solely responsible for GR in the TennGR goosegrass population.

关键词： herbicide resistance monogenic trait glyphosate PCR amplification of specific alleles (PASA) Epsps target-site mutation

Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams

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Chinese Physics Letters 2018年第2期35卷 29-33页

作者： j.Shiri F.Shahi M.R.Mehmannavaz L.Shahrassai Young Researchers and Elite Club Tabriz BranchIslamic Azad University Department of Atomic and Molecular Physics University of Tabriz Young Researchers and Elite Club Mashhad BranchIslamic Azad University

We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot *** show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser *** and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching *** estimated range is between 5-8 ps for subluminal to superluminal light propagation.

关键词： Phase Control of Transient Optical Properties of Double Coupled Quantum-Dot Nanostructure via Gaussian Laser Beams QDs

Roles of manganese in photosystem II dynamics to irradiations and temperatures

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Frontiers in Biology 2013年第3期8卷 312-322页

作者： Xuejing HOU Harvey j. M. HOU Department of Chemistry and Biochemistry University of Massachusetts Dartmouth North Dartmouth MA 02747 USA Department of Physical Sciences Alabama State University Montgomery AL 36104 USA

The most amazing chemistry is the light-driven water splitting reaction occurred in the oxygen-evolving complex of phototsystem II in higher plants, green algae, and cyanobacteria. Mn, in the form of Mn4CaOs cluster in photosystem II, is responsible for the catalytic water splitting reaction as well as plays roles in photosystem II dynamics to irradiation and temperatures. Manganese hypothesis of UV-initiated photoinhibition as a direct target is established, and thermal inactivation of photosystem II involves the valence and structural changes of manganese. Recent progresses in understanding the roles of manganese in photoinhibition especially under UV light and in thermal inactivation including elevated temperatures using synthetic models and native ps II complexes are summarized and evaluated. Potential problems and possible solutions are discussed and presented.

关键词： photosynthesis manganese photosystem II irradiation temperature stress