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Molecular Plant 2010年第5期3卷 834-841页

作者： Brian D. Keppler allan M. Showalter Department of Environmental and Plant Biology Molecular and Cellular Biology Program Ohio University 315 Porter Hall Athens OH 45701-2979 USA

IRX14 and IRX14-LIKE （IRX14L） are two closely related glycosyl transferases in the glycosyl transferase 43 （GT43） family of Arabidopsis. A T-DNA insertion mutant for IRX14 results in comparatively minor changes, such as irregular xylem, while a mutation for IRX14L results in no changes. However, an irx14 and irx14L double mutant severely affects growth and development, with the dwarf plants failing to produce an inflorescence stem. Plants that are homozygous for IRX14 but heterozygous for IRX14L （irx14 irx14L（±）） exhibit an intermediate phenotype, including noticeably smaller leaves, stems, and underdeveloped siliques. Additionally, the T-DNA insertion mutant for IRX14 was found to result in a drought-tolerant phenotype. Carbohydrate analysis of total cell wall extracts revealed a reduction in xylose for the irx14 and irx14 irx14L（±） mutants, consistent with a defect in glucuronoxylan biosynthesis. Immunolocalization of xylan with the LM10 antibody revealed a loss of xylan in irx14 mutants and a further reduction in the irx14 irx14L（±） mutants. IRX14L likely functions redundantly with IRX14 in glucuronoxylan biosynthesis, with IRX14 having a more important role in the process.

关键词： Abiotic/environmental stress cell walls genetics Arabidopsis irregular xylem xylan.

SYNTHESIS OF POLYMERS CONTAINING N-N LINKAGES

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Chinese Journal of Polymer Science 2003年第5期21卷 541-550页

作者： Zaza Gomurashvili allan S.Hay Department of Chemistry McGill University 801 Sherbrooke Street West Montreal Ouebec Canada H3A 2K6Department of Chemistry McGill University 801 Sherbrooke Street West Montreal Ouebec Canada H3A 2K6

The N--N linkage in hydrazine is thermally stable when it is tetrasubstituted and there are electron-withdrawinggroups attached to the nitrogen atoms. Our research on the synthesis of polymers contaning N--N linkages is reviewed. TheN,N-bisimide structure has been introduced in the backbone of polymers as well as a pendant group in poly(aryl ether)s togive very thermoxidatively stable polymers with very high glass transition temperatures. Most of the polymers form tough,flexible films. N-Aminotriazoles also form stable imides by reaction with anhydrides and these N-imidotriazole groups havebeen introduced as pendent groups on poly(aryl ether)s. The polymers are highly fluorescent materials. Three methods for thesynthesis of polymers containing the tetrasubstituted-azine structure will be discussed: (1) oxidative coupling of bisimines;(2) condensation of bishydrazones with diketones; (3) poly(aryl ether azines) from the azine formed from 4-fluorobenzo-phenone by reaction with salts of bisphenols.

关键词： Hydrazine N-N-linkage N-aminoimide Poly(imidoaryll ether) N-aminotriazole Polyazine

Unified methodology for site-characterization and sampling of highway runoff

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Frontiers of Environmental Science & Engineering 2010年第1期4卷 47-58页

作者： Jy S.WU Craig J.allan Department of Civil and Environmental Engineering University of North Carolina at CharlotteCharlotteNC 28223USA 2 Department of Geography and Earth SciencesUniversity of North Carolina at CharlotteCharlotteNC 28223USA

Hydrology,roadway traffic conditions,and atmospheric deposition are three essential data categories for the planning and implementation of highway-runoff monitoring and characterization *** variables pertaining to each data category could be site specific but have been shown to correlate with runoff pollutant *** data categories were combined to derive statistical relationships for characterization and prioritization of the respective pollutant loads at highway runoff *** runoff data of total suspended solids(TSS),total dissolved solid(TDS),chemical oxygen demand(COD),total Kjeldahl nitrogen(TKN)and total phosphorus(TP)collected from three highway sites in Charlotte,North Carolina,USA,were used to illustrate the development of site-specific highway-runoff pollutant loading *** unified methodology provides a basis for initial assessment of the pollutant-constituent loads from highway runoff using hydrologic component *** reliability is achievable when additional traffic and/or atmospheric component variables are incorporated into the basic hydrologic regression *** addition,operational guidance is suggested for implementing highway-runoff monitoring programs that are subject to sampling and resources constraints.

关键词： highway runoff pollutant loads regression models non-point source pollution storm water permit

An unusual enteropathy-associated T-cell lymphoma with MYC translocation arising in a Japanese patient:A case report

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World Journal of Gastroenterology 2012年第19期18卷 2434-2437页

作者： Kenji Okumura Masahiko Ikebe Tatsuro Shimokama Morishige Takeshita Nao Kinjo Keishi Sugimachi Hidefumi higashi Department of Surgery Nippon Steel Yawata Memorial HospitalKitakyushu 805-8508Japan Department of Pathology Nippon Steel Yawata Memorial HospitalKitakyushu 805-8508Japan Department of Pathology School of MedicineFukuoka UniversityFukuoka 814-0180Japan

Enteropathy-associated T-cell lymphoma （EATL） is a rare peripheral T-cell lymphoma classified into 2 types, with or without celiac disease, based on histology. Type 2 EATL is less commonly associated with celiac disease, in which cells are characterized by being monomorphic and small- to medium-sized. Cells are characterized by CD8 and CD56 expression and c-MYC oncogene locus gain. We present an atypical case of type 2 EATL in the jejunum, with human T-lymphotropic virus-1 that was CD4- CDS＋ CD56- CD30- CD25- TIA-I＋ and granzyme B＋ on immunohistological staining. It also displayed translocation of chromosome 8p24 （c-MYC）, as de- termined by fluorescent/n situ hybridization. Mucosalspreading and intraepithelial invasion by lymphoma with villous atrophy were detected adjacent to the mucosal layer. The lymphoma may be derived from in- traepithelial CD8＋ T cells, similar to celiac disease.

关键词： Enteropathy-associated T-cell lymphoma Celiac disease Human T-lymphotropic virus-l Fluores-cent in situ hybridization Chromosome 8p24

FORCED OSCILLATION OF SECOND ORDER DIFFERENTIAL EQUATIONS WITH MIXED NONLINEARITIES

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Acta Mathematica Scientia 2011年第2期31卷 613-626页

作者： Taher S. Hassan Lynn Erbe allan Peterson Department of Mathematics Faculty of Science Mansoura University Department of Mathematics University of Nebraska-Lincoln

This article is concerned with the oscillation of the forced second order differ- ential equation with mixed nonlinearities（a（t）（x＇（t））γ）＇＋po（t）xγ（go（t））＋n∑t=1pi（t）｜x（gi（t））｜αi sgn x（gi（t））=e（t）,where γ is a quotient of odd positive integers αi〉0,i=1,2 ……n,a,e,and pi ∈ C（[0,∞）R）,a（t）〉0,gi：R→R are positive continuous functions on R with lim gi （t）=∞,i=0,1,……,n. Our results generalize and improve the results in a recent article by Sun and Wong[29].

关键词： Oscillation functional differentail equations second order

Involvement of SNX1 in regulating EGFR endocytosis in a gefitinib-resistant NSCLC cell lines

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Cancer Drug Resistance 2019年第3期2卷 539-549页

作者： yukio Nishimura Kazuyuki Itoh Division of Pharmaceutical Cell Biology Graduate School of Pharmaceutical SciencesKyushu UniversityFukuoka 812-8582Japan Research Institute Nozaki Tokushukai(RINT) Osaka 574-0074Japan.

The drug gefitinib, a specific inhibitor of EGFR tyrosine kinase, has been shown to suppress the activation of EGFR signaling for survival and cell proliferation in non-small cell lung cancer cell lines. For many years, EGFR endocytosis has served as a model for investigating ligand-induced, receptor-mediated endocytosis. On EGF stimulation, EGFR is internalized and transported via clathrin-coated vesicles to early endosomes, and EGFR then recruits and phosphorylates signaling molecules, leading to the activation of downstream signaling such as MAPK/PI3K/AKT pathways-an important mechanism for regulating cell growth. Once delivered to the lysosomes, EGFR is degraded to terminate intracellular EGFR signaling via endocytosis;this process is known as receptor downregulation. Therefore, the endocytosis of EGFR is closely related with attenuation of intracellular EGFR signaling. Alternatively, EGFR is returned to cell surface from early endosomes for the continued signaling. Previous reports revealed that a competent EGF-induced endocytosis of EGFR followed by its rapid downregulation efficiently proceeds in the gefitinib-sensitive NSCLC cell lines. In contrast, gefitinib-resistant cell lines showed that EGFR endocytosis is impaired and the internalized EGFR is aggregated in the early endosomes, which is associated with the overexpressed sorting nexin 1 (SNX1), initially identified as a protein that interacts with EGFR. Thus dysregulated EGFR endocytosis is implicated in gefitinib resistance, as it leads to uncontrolled signal transduction. At present, the therapeutic relevance of EGFR endocytosis with regard to drug resistance in lung cancer has not been clarified. This review focused on the mechanism for EGFR endocytosis associated with SNX1 trafficking in gefitinib-resistant lung cancer cells.

关键词： Lung cancer drug-resistance EGFR endocytosis endosomes/lysosomes sorting nexin 1 membrane recycling

Modulation of mitochondrial respiration underpins neuronal differentiation enhanced by lutein

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Neural Regeneration Research 2019年第1期14卷 87-99页

作者： Kui Xie Sherry Ngo Jing Rong allan Sheppard Liggins Institute University of Auckland

Lutein is a dietary carotenoid of particular nutritional interest as it is preferentially taken up by neural tissues. Often linked with beneficial effects on vision, a broader role for lutein in neuronal differentiation has emerged recently, although the underlying mechanisms for these effects are not yet dear. The purpose of this study was to investigate the effect of lutein on neuronal differentiation and explore the associated underpinning mechanisms. We found that lutein treatment enhanced the differentiation of SH-SYSY cells, specifically increasing neuronal arborization and expression of the neuronal process filament protein microtubule-associated protein 2. This effect was mediated by the intracellular phosphoinositide-3-kinase （PI3K） signaling pathway. While PI3K activity is a known trigger of neuronal differentiation, more recently it has also been shown to modulate the metabolic state of cells. Our analysis of bioenergetics found that lutein treatment increased glucose consumption, rates of glycolysis and enhanced respiratory activity of mitochondrial complexes. Concomitantly, the generation of reactive oxygen species was increased （con- sistent with previous reports that reactive oxygen species promote neuronal differentiation）, as well as the production of the key metabolic intermediate acetyl-CoA, an essential determinant of epigenetic status in the cell. We suggest that lutein-stimulated neuronal differentiation is mediated by PI3K-dependent modulation of mitochondrial respiration and signaling, and that the consequential metabolic shifts initiate epigenetically dependent transcriptomic reprogramming in support of this morphogenesis. These obser- vations support the potential importance of micronutrients supplementation to neurogenesis, both during normal development and in regenerative repair.

关键词： lutein micronutrient neuronal differentiation metabolism PI3K-AKT pathway glycolysis mitochondria gene expression

Effect of phosphate on heterogeneous Fenton oxidation of catechol by nano-Fe_(3)O_(4):Inhibitor or stabilizer?

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Journal of Environmental Sciences 2016年第1期28卷 69-76页

作者： Xiaofang Yang Jie He Zhongxi Sun allan Holmgren Dongsheng Wang Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Chemistry and Chemical Engineering University of JinanJinan 250022China Chemical Engineering Department of CivilEnvironmental and Natural Resources EngineeringLulea University of TechnologySE-971 87Sweden

The effect of phosphate on adsorption and oxidation of catechol, 1,2-dihydroxybenzene,in a heterogeneous Fenton system was investigated. In situ attenuated total reflectance infrared spectroscopy（ATR-FTIR） was used to monitor the surface speciation at the nano-Fe_3O_4 catalyst surface. The presence of phosphate decreased the removal rate of catechol and the abatement of dissolved organic compounds, as well as the decomposition of H2O2. This effect of phosphate was mainly due to its strong reaction with surface sites on the iron oxide catalyst. At neutral and acid pH, phosphate could displace the adsorbed catechol from the surface of catalyst and also could compete for surface sites with H2O2. In situ IR spectra indicated the formation of iron phosphate precipitation at the catalyst surface. The iron phosphate surface species may affect the amount of iron atoms taking part in the catalytic decomposition of H2O2 and formation of hydroxyl radicals,and inhibit the catalytic ability of Fe3O4 catalyst. Therefore, phosphate ions worked as stabilizer and inhibitor in a heterogeneous Fenton reaction at the same time, in effect leading to an increase in oxidation efficiency in this study. However, before use of phosphate as pH buffer or H2O2 stabilizer in a heterogeneous Fenton system, the possible inhibitory effect of phosphate on the actual removal of organic pollutants should be fully considered.

关键词： Heterogeneous Fenton oxidation Adsorption ATR-FTIR Interface mechanism

Potential of organic waste to energy and bio-fertilizer production in Sub-Saharan Africa:a review

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Waste Disposal and Sustainable Energy 2023年第3期5卷 259-267页

作者： Isaac Rubagumya allan John Komakech Isa Kabenge Nicholas Kiggundu Department of Agricultural and Biosystems Engineering Makerere UniversityP.O.Box 7062KampalaUganda

Many growing cities of Sub-Saharan Africa(SSA)are marred by the inefficient collection,management,disposal and reuse of organic *** purpose of this study was to review and compare the energy recovery potential as well as bio-fertilizer perspective,from the organic waste volumes generated in SSA *** on computations made with a literature review,we find that the amount of organic wastes varies across countries translating to differences in the energy and bio-fertilizer production potentials across *** wastes generated in SSA can potentially generate about 133 million GWh of energy per *** organic waste to bio-fertilizer production potentials range from 11.08 million tons to 306.26 million tons *** has the highest energy and bio-fertilizer potential among the SSA countries with a total per capita of 630 MWh/year and 306.26 million tons,*** challenges and technical considerations for energy and bio-fertilizer approaches in the management of organic waste in SSA have also been *** study is of help to the readers and strategic decision makers in understanding the contribution of bioenergy and bio-fertilizer to achieving sustainable development goals,namely,7(Affordable and Clean Energy)and 13(Climate Action)in SSA.

关键词： Sub-Saharan Africa Organic waste Energy production Bio-fertilizer production Challenges

Development of Simultaneous HPLC-Fluorescence Assay of Phenol and Chlorophenols in Tap Water after Pre-Column Derivatization with 3-Chlorocarbonyl-6,7-dimethoxy-1- methyl-2(1H)-quinoxalinone

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Detection 2016年第1期4卷 16-24页

作者： Yasuhiko higashi Department of Analytical Chemistry Faculty of Pharmaceutical Sciences Hokuriku University Kanazawa Japan

Chlorophenols (2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and 2,4, 6-trichlorophenol) may be presented in natural waters or drinking water as a result of disinfection processes involving chlorination, or as contaminants derived from domestic products, industrial operations and agricultural chemicals. A previous HPLC-UV method for determination of phenol and five chlorophenols in tap water using 4-fluoro-7-nitro-2,1,3-benzoxadiaole as a UV labeling reagent shows limited sensitivity. Here, we present an improved HPLC-fluorescence detection method for simultaneous determination of phenol and the above chlorophenols in tap water after pre-column derivatization with 3-chlorocarbonyl-6,7-dimethoxy-1-methyl-2(1H)-quino- xalinone (DMEQ-COCl), using a short, narrow column (50 × 2.1 mm i.d., packed with 5 μm particles of C18 material) to improve the sensitivity. Standard samples containing the compounds are derivatized with DMEQ-COCl in borate buffer (pH 9.0) at room temperature for 3 mins. The response is linear in the concentration range of 0.01 - 0.05 to 0.5 mg/L with r2 values ≥0.9967 for all compounds. The lower limits of detection are 0.001 to 0.008 mg/L, and the coefficients of variation are less than 8.8%. The recovery values from tap water spiked with standard samples are satisfactory. The present method is suitable for examining whether or not tap water samples are contaminated with phenol and chlorophenols in excess of regulatory values.

关键词： Phenol Chlorophenol Fluorescence Derivatization 3-Chlorocarbonyl-6 7-dimethoxy-1-methyl-2(1H)-quinoxalinone