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Journal of Rare Earths 2013年第10期31卷 1009-1016页

作者： T. F. Abbs Fen Reji A. Jeena Pearl Bojaxa A. Rosy Department of Chemistry & research centre Nesamony Memorial Christian College Department of Chemistry& research centre Scott Christian College Department of Botany & research centre Holy Cross College (Autonomous)

Lanthanide complexes of Eu（III）, Gd（III）, Nd（III）, Sm（III）, and Tb（III） with phenylthioacetic acid were synthesized and characterized by elemental analysis, mass, infrared radiation （IR）, electronic spectra, molar conductance, thermogravimetric analysis （TGA）, and powder X-ray diffraction （XRD）. The results showed that the lanthanide complexes were homodinuclear in nature. The two lanthanide ions were bridged by eight oxygen atoms from four carboxylate groups. Thermal decomposition profiles were consis- tent with the proposed formulations. Powder XRD studies showed that all the complexes were amorphous in nature. Antimicrobial studies indicated that these complexes exhibited more activity than the ligand itself. The DNA cleavage activity of the ligand and its complexes were assayed on CT DNA using gel electrophoresis in the presence of H202. The result showed that the Eu（Ⅲ） and Nd（Ⅲ） complexes completely cleaved the DNA. The anticancer activities of the complexes were also studied towards human cervical cancer cell line （HeLa） and colon cancer cells （HCT116） and it was found that the Eu（Ⅲ） and Nd（Ⅲ） complexes were more active than the corresponding Gd（Ⅲ）, Sm（Ⅲ）, Tb（Ⅲ） complexes and the free ligand on both the cancer cells.

关键词： lanthanide complexes phenylthioacetic acid antimicrobial DNA cleavage anticancer rare earths

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Injection-switchable erbium-doped fiber laser with two output ports

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Chinese Optics Letters 2007年第2期5卷 96-98页

作者：陈达如秦山 centre for Optical and Electromagnetic research Joint Research Centre of Optical CommunicationsZhejiang UniversityHangzhou 310058

An injection-switchable erbium-doped fiber laser （EDFL） with two output ports based on a ring structure is proposed. Wavelength switching together with the switching of the dominating output port of the fiber laser is achieved by controlling the power of a tunable injection laser. The characteristics of the wavelength switching for different levels of the pump laser power and different wavelengths of the injection laser are studied experimentally.

关键词： Injection lasers Switching Wavelength

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Drug resistance in the sexually transmitted protozoan Trichomonas vaginalis

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Cell research 2003年第4期13卷 239-249页

作者： REBECCA L DUNNE,LINDA A DUNN,PETER UPCROFT,PETERJO’DONOGHUE,JACQUELINE A UPCROFT The Queensland Institute of Medical research The Australian centre for International and Tropical health and Nutrition Brisbane Queensland 4029 Australia Tie School of Molecular and Microbial Science University of Queensland Brisbane Queensland 4072 Australia The Queensland Institute of Medical research The Australian centre for International and Tropical health and Nutrition Brisbane Queensland 4029 Australia The Queensland Institute of Medical research The Australian centre for International and Tropical health and Nutrition Brisbane Queensland 4029 Australia The School of Molecular and Microbial Science University of Queensland Brisbane Queensland 4072 Australia The Queensland Institute of Medical research The Australian centre for International and Tropical health and Nutrition Brisbane Queensland 4029 Australia

Trichomoniasis is the most common, sexually transmitted infection. It is caused by the flagellated protozoan parasite Trichomonas vaginalis. Symptoms include vaginitis and infections have been associated with preterm delivery, low birth weight and increased infant mortality, as well as predisposing to HIV/AIDS and cervical cancer. Trichomoniasis has the highest prevalence and incidence of any sexually transmitted infection. The 5-nitroimidazole drugs, of which metronidazole is the most prescribed, are the only approved, effective drugs to treat trichomoniasis. Resistance against metronidazole is frequently reported and cross resistance among the family of 5-nitroimidazole drugs is common, leaving no alternative for treatment, with some cases remaining unresolved. The mechanism of metronidazole resistance in T. vaginalis from treatment failures is not well understood, unlike resistance which is developed in the laboratory under increasing metronidazole pressure. In the latter situation, hydrogenosomal fu

关键词： Trichomonas vaginalis metronidazole pyruvate: ferredoxin oxidoreductase ferredoxin hydrogenase drug resistance.

Forecasting the effects of EU policy measures on the nitrate pollution of groundwater and surface waters

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Journal of Environmental Sciences 2010年第6期22卷 872-877页

作者： Ralf Kunkel Peter Kreins Bjrn Tetzlaff Frank Wendland research centre Jülich Institute of Chemistry and Dynamics of the Geosphere Institute of Rural Studies Federal Agricultural Research Centre

We used the interdisciplinary model network REGFLUD to predict the actual mean nitrate concentration in percolation water at the scale of the Weser river basin （Germany） using an area differentiated （100 m × 100 m） approach. REGFLUD combines the agro-economic model RAUMIS for estimating nitrogen surpluses and the hydrological models GROWA/DENUZ for assessing the nitrate leaching from the soil. For areas showing predicted nitrate concentrations in percolation water above the European Union （EU） groundwater quality standard of 50 mg NO3-N/L, effective agri-environmental reduction measures need to be derived and implemented to improve groundwater and surface water quality by 2015. The effects of already implemented agricultural policy are quantified by a baseline scenario projecting the N-surpluses from agricultural sector to 2015. The REGFLUD model is used to estimate the effects of this scenario concerning groundwater and surface water pollution by nitrate. From the results of the model analysis the needs for additional measures can be derived in terms of required additional N-surplus reduction and in terms of regional prioritization of measures. research work will therefore directly support the implementation of the Water Framework Directive of the European Union in the Weser basin.

关键词： catchment management diffuse source pollution mitigation methods river basin management Water Framework Directive

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Glutamate transporters, EAAT1 and EAAT2, are potentially important in the pathophysiology and treatment of schizophrenia and affective disorders

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World Journal of Psychiatry 2018年第2期8卷 51-63页

作者： Georgia M Parkin Madhara Udawela Andrew Gibbons Brian Dean Molecular Psychiatry Laboratory the Florey Institute of Neuroscience and Mental Health CRC for Mental health research centre for Mental health the Faculty of Health Arts and Design Swinburne University

Glutamate is the predominant excitatory neurotransmitter in the human brain and it has been shown that prolonged activation of the glutamatergic system leads to nerve damage and cell death. Following release from the pre-synaptic neuron and synaptic transmission, glutamate is either taken up into the presynaptic neuron or neighbouring glia by transmembrane glutamate transporters. Excitatory amino acid transporter(EAAT) 1 and EAAT2 are Na+-dependant glutamate transporters expressed predominantly in glia cells of the central nervous system. As the most abundant glutamate transporters, their primary role is to modulate levels of glutamatergic excitability and prevent spill over of glutamate beyond the synapse. This role is facilitated through the binding and transportation of glutamate into astrocytes and microglia. The function of EAAT1 and EAAT2 is heavily regulated at the levels of gene expression, post-transcriptional splicing, glycosylation states and cell-surface trafficking of the protein. Both glutamatergic dysfunction and glial dysfunction have been proposed to be involved in psychiatric disorder. This review will present an overview of the roles that EAAT1 and EAAT2 play in modulating glutamatergic activity in the human brain, and mount an argument that these two transporters could be involved in the aetiologies of schizophrenia and affective disorders as well as represent potential drug targets for novel therapies for those disorders.

关键词： Glia Excitatory amino acid transporter Psychiatry Affective disorders Glutamate transporter Glutamate Schizophrenia

Measurement of serum paraoxonase-1 activity in the evaluation of liver function

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World Journal of Gastroenterology 2009年第16期15卷 1929-1933页

作者： Jordi Camps Judit Marsillach Jorge Joven centre of Biomedical research University Hospital Sant JoanInstitute of Health Research Pere VirgiliUniversity Rovira i Virgili

Paraoxonase-1 (PON1) is an esterase and lactonase synthesized by the liver and found in the circulation associated with high-density lipoproteins. The physiological function of PON1 seems to be to degrade specific oxidized cholesteryl esters and oxidized phospholipids in lipoproteins and cell membranes. PON1 is, therefore, an antioxidant enzyme. Alterations in circulating PON1 levels have been reported in a variety of diseases involving oxidative stress including chronic liver diseases. Measurement of serum PON1 activity has been proposed as a potential test for the evaluation of liver function. However, this measurement is still restricted to research and has not been extensively applied in routine clinical chemistry laboratories. The reason for this restriction is due to the problem that the substrate commonly used for PON1 measurement, paraoxon, is toxic and unstable. The recent development of new assays with non-toxic substrates makes this proposal closer to a practical development. The present editorial summarizes PON1 biochemistry and function, its involvement with chronic liver impairment, and some aspects related to the measurement of PON1 activity in circulation.

关键词： Lipoproteins Liver cirrhosis Liver function tests Oxidative stress Paraoxonase-1

A High-order Coupled Compact Integrated RBF Approximation Based Domain Decomposition Algorithm for Second-order Differential Problems

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Computer Modeling in Engineering & Sciences 2015年第4期104卷 251-304页

作者： C.M.T.Tien N.Pham-Sy N.Mai-Duy C.-D.Tran T.Tran-Cong Computational Engineering and Science research centre Faculty of HealthEngineering and SciencesThe University of Southern QueenslandToowoombaQueensland 4350Australia

This paper presents a high-order coupled compact integrated RBF(CC IRBF)approximation based domain decomposition(DD)algorithm for the discretisation of second-order differential *** Schwarz DD algorithms,including one-level additive/multiplicative and two-level additive/multiplicative/hybrid,are *** CCIRBF based DD algorithms are analysed with different mesh sizes,numbers of subdomains and overlap sizes for Poisson *** convergence analysis shows that the CCIRBF two-level multiplicative version is the most effective algorithm among various schemes employed ***,the present CCIRBF two-level method converges quite rapidly even when the domain is divided into many subdomains,which shows great promise for either serial or parallel *** practical tests,we then incorporate the CCIRBF into serial and parallel two-level multiplicative *** numerical examples,including those governed by Poisson and Navier-Stokes equations are analysed to demonstrate the accuracy and efficiency of the serial and parallel algorithms implemented with the *** results show:(i)the CCIRBF-Serial and-Parallel algorithms have the capability to reach almost the same solution accuracy level of the CCIRBF-Single domain,which is ideal in terms of computational calculations;(ii)the CCIRBF-Serial and-Parallel algorithms are highly accurate in comparison with standard finite difference,compact finite difference and some other schemes;(iii)the proposed CCIRBF-Serial and-Parallel algorithms may be used as alternatives to solve large-size problems which the CCIRBF-Single domain may not be able to deal *** ability of producing stable and highly accurate results of the proposed serial and parallel schemes is believed to be the contribution of the coarse mesh of the two-level domain decomposition and the CCIRBF *** is noted that the focus of this paper is on the derivation of highly accurate serial and parallel algorithms

关键词： Coupled compact integrated RBF (CCIRBF) Schwarz domain decomposition one-level two-level coarse meshes additive multiplicative hybrid serial parallel colouring technique Poisson equation Naiver-Stokes equation liddriven cavity

Novel understanding of ABC transporters ABCB1/MDR/P-glycoprotein, ABCC2/MRP2, and ABCG2/BCRP in colorectal pathophysiology

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World Journal of Gastroenterology 2015年第41期21卷 11862-11876页

作者： Vibeke Andersen Katrine Svenningsen Lina Almind Knudsen Axel Kornerup Hansen Uffe Holmskov Allan Stensballe Ulla Vogel Molecular Diagnostic and Clinical health research Unit Hospital of Southern Jutland Institute of Regional health research-centre S?nderjylland University of Southern Denmark Medical Department Regional Hospital Viborg Experimental Animal Models University of Copenhagen Department of Cancer and Inflammation research University of Southern Denmark Department of health Science and Technology Aalborg University National research centre for the Working Environment

AIM: To evaluate ATP-binding cassette(ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer(CRC) development. METHODS: Literature search was conducted on Pub Med using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohns disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein(P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2(MRP2) and ABCG2/breast cancer resistance protein(BCRP), Abcb1/Mdr1 a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function. RESULTS: Recently, human studies reported thatchanges in the levels of ABC transporters were early events in the adenoma-carcinoma sequence leading to CRC. A link between ABCB1, high fat diet and gut microbes in relation to colitis was suggested by the animal studies. The finding that colitis was preceded by altered gut bacterial composition suggests that deletion of Abcb1 leads to fundamental changes of hostmicrobiota interaction. Also, high fat diet increases the frequency and severity of colitis in specific pathogenfree Abcb1 KO mice. The Abcb1 KO mice might thus serve as a model in which diet/environmental factors and microbes may be controlled and investigated in relation to intestinal inflammation. Potential molecular mechanisms include defective transport of inflammatory mediators and/or phospholipid translocation from one side to the other of the cell membrane lipid bilayer by ABC transporters affecting inflammatory response and/or function of tight junctions, phagocytosis and vesicle trafficking. Also, diet and microbes give rise to molecules which are potential substrates for the ABC transporters and which may additionally affect ABC transporter function through nuclear receptors and transcriptional regulation. Another critical role of ABCB1 was suggested by the finding that ABCB1 expr

关键词： ATP-binding cassette transporters Colorectal cance

Impact of single annual treatment and four-monthly treatment for hookworm and Ascaris lumbricoides,and factors associated with residual infection among Kenyan school children

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Infectious Diseases of Poverty 2017年第1期6卷 249-260页

作者： Stella Kepha Charles S.Mwandawiro Roy M.Anderson Rachel L.Pullan Fred Nuwaha Jorge Cano Sammy M.Njenga Maurice R.Odiere Elizabeth Allen Simon J.Brooker Birgit Nikolay School of Public health Makerere University College of Health SciencesKampalaUganda Eastern and Southern Africa centre of International Parasite Control Kenya Medical Research Institute(KEMRI)NairobiKenya London centre for Neglected Tropical Disease research Department of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK London School of Hygiene and Tropical Medicine LondonUK centre for Global health research KEMRIKisumuKenya KEMRI-Wellcome Trust research Programme NairobiKenya

Background:School-based deworming is widely implemented in various countries to reduce the burden of soil-transmitted helminths(STHs),however,the frequency of drug administration varies in different *** this study,we compared the impact of a single annual treatment and 4-monthly treatment over a follow-up among Kenyan school children,and investigated the factors associated with residual ***:We performed a secondary analysis of data from a randomized trial investigating whether deworming for STHs alters risk of acquiring *** received either a single treatment or 4-monthly albendazole treatments were followed longitudinally from February 2014 to October *** relative impact of treatment and factors associated with residual infections were investigated using mixed-effects regression *** to infection was assessed based on Spearman’s rank and Kendall’s Tau correlation ***:In the 4-monthly treatment group,the proportion of children infected with hookworm decreased from 59.9 to 5.7%,while Ascaris lumbricoides infections dropped from 55.7 to 6.2%.In the single treatment group,hookworm infections decreased over the same time period from 58.7 to 18.3%(12.6%absolute difference in reduction,95%CI:8.9-16.3%),and *** from 56.7 to 23.3%(17.1%absolute difference in reduction,95%CI:13.1-21.1%).There was strong evidence for predisposition to both STH *** hookworm infection among children on 4-monthly treatment were associated with male sex and baseline nutritional status,whereas *** infection was associated with individual and school-level infection at baseline,latrine cleanliness at ***:This study found that 4-monthly treatment w more effective than single annual *** treatments led to dramatic reductions in the intensities of STHs,but did not completely clear infections among school children in Kenya,a presumed reflection of reinfection in a setti

关键词： School-based deworming Soil-transmitted helminths Albendazole School children Kenya

Neuroprotection by misoprostol against rotenone-induced neurotoxicity in rat brain

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Asian Pacific Journal of Tropical Medicine 2018年第1期11卷 40-47页

作者： Omar M.E.Abdel-Salam Amany A Sleem Eman R Youness Nadia A Mohammed Enayat A Omara Department of Toxicology and Narcotics National Research Centre Department of Pharmacology National Research Centre Department of Medical Biochemistry National Research Centre Department of Pathology National Research Centre

Objective: To investigate the effect of the prostaglandin E1 analogue misoprostol on oxidative stress and neurodegeration caused by subcutaneous rotenone administration in rats. Methods:Rotenone was administered in a dose of 1.5 mg/kg every other day for 2 weeks. Starting from the 1 st day of rotenone injection, rats were subcutaneously treated with misoprostol at doses of10, 100 or 1 000 μg/kg. Rats were evaluated for brain lipid peroxidation(malondialdehyde:MDA), reduced glutathione(GSH), nitric oxide(NO) levels, and paraoxonase-1(PON-1) *** concentrations of the anti-apoptotic protein B cell/lymphoma-2(Bcl-2) were determined in the striatum. Histopathologic examination and the expression of inducible nitric oxide synthase(iNOS) in the cerebral cortex and striatum were also performed. Results: Compared with the vehicle-treated group, rotenone caused a significant increase in brain lipid proxidation(MDA)by 61%(P<0.05) accompanied by an increase in NO by 73.1%(P<0.05) and a decrease in GSH concentration by 29.4%(P<0.05). In addition, brain PON-1 activity significantly decreased by63.0%(P<0.05) and striatal Bcl-2 significantly decreased by 27.9%(P<0.05) with respect to the corresponding control value. Brain sections from rotenone treated rats showed extensive dark pyknotic and apoptotic nuclei in neurons, shrunken cytoplasm and perineuronal *** also caused pronounced expression of iNOS in the cerebral cortex and *** with misoprostol at doses of 100 and 1 000 μg/kg resulted in decreased brain MDA(by 16.5%-23.0%)(P<0.05) and NO levels(by 37.1%-40.7%)(P<0.05) and increased GSH concentrations(by 18.8%-30.1%)(P<0.05). PON-1 activity was significantly increased by80.0%-114.8%(P<0.05) by misoprostol at 100 and 1 000 μg/kg, respectively. In addition,misoprostol treatment restored striatal Bcl-2 concentrations to its normal value. Misoprostol treatment resulted in markedly reduced brain injury and decreased iNOS expression in the cereb

关键词： Misoprostol Rotenone Brain oxidative stress B cell/lymphoma-2 Paraoxonase