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Metabolomic studies in the inborn error of metabolism alkaptonuria reveal new biotransformations in tyrosine metabolism

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Genes & Diseases 2022年第4期9卷 1129-1142页

作者： brendan P.Norman Andrew S.Davison Juliette H.hughes Hazel Sutherland Peter J.M.Wilson Neil G.berry Andrew T.hughes Anna M.Milan Jonathan C.Jarvis Norman b.Roberts Lakshminarayan R.Ranganath George bou-Gharios James A.gallagher Institute of Life Course and Medical Sciences University of LiverpoolWilliam Henry Duncan Building6 West Derby StreetLiverpoolL78TXUK Department of Clinical biochemistry&Metabolic Medicine Liverpool Clinical LaboratoriesRoyal Liverpool University HospitalPrescot StreetLiverpoolL78XPUK School of Sport&Exercise Sciences Liverpool John Moores UniversityTom Reilly BuildingByrom StreetLiverpoolL33AFUK Department of Chemistry University of LiverpoolCrown StreetLiverpoolL697ZDUK

Alkaptonuria (AKU) is an inherited disorder of tyrosine metabolism caused by lack of active enzyme homogentisate 1,2-dioxygenase (HGD). The primary consequence of HGD deficiency is increased circulating homogentisic acid (Hga), the main agent in the pathology of AKU disease. Here we report the first metabolomic analysis of AKU homozygous Hgd knockout (Hgd−/−) mice to model the wider metabolic effects of Hgd deletion and the implication for AKU in humans. Untargeted metabolic profiling was performed on urine from Hgd−/− AKU (n = 15) and Hgd+/− non-AKU control (n = 14) mice by liquid chromatography high-resolution time-of-flight mass spectrometry (Experiment 1). The metabolites showing alteration in Hgd−/− were further investigated in AKU mice (n = 18) and patients from the UK National AKU Centre (n = 25) at baseline and after treatment with the Hga-lowering agent nitisinone (Experiment 2). A metabolic flux experiment was carried out after administration of 13C-labelled Hga to Hgd−/−(n = 4) and Hgd+/−(n = 4) mice (Experiment 3) to confirm direct association with Hga. Hgd−/− mice showed the expected increase in Hga, together with unexpected alterations in tyrosine, purine and TCA-cycle pathways. Metabolites with the greatest abundance increases in Hgd−/− were Hga and previously unreported sulfate and glucuronide Hga conjugates, these were decreased in mice and patients on nitisinone and shown to be products from Hga by the 13C-labelled Hga tracer. Our findings reveal that increased Hga in AKU undergoes further metabolism by mainly phase II biotransformations. The data advance our understanding of overall tyrosine metabolism, demonstrating how specific metabolic conditions can elucidate hitherto undiscovered pathways in biochemistry and metabolism.

关键词： Alkaptonuria biotransformation Metabolism Metabolomics Mice

Tailoring thermoelectric properties of Zr(0.43)Hf(0.57)NiSn half-Heusler compound by defect engineering

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Rare Metals 2020年第6期39卷 659-670页

作者： Krzysztof galazka Wenjie Xie Sascha Populoh Myriam H.Aguirre Songhak yoon Gesine büttner Anke Weidenkaff Institute of Plasma Physics and Laser Microfusion Warsaw 01-497Poland Department of Materials Science Technische Universitat DarmstadtDarmstadt 64287Germany Laboratory for Solid State Chemistry and Catalysis EmpaDlibendorf 8600Switzerland Instituto de Nanociencia de Aragon Universidad de ZaragozaSaragossa 50018Spain Departamento de Fisica de la Materia Condensada Universidad de ZaragozaSaragossa 50009Spain Laboratorio de Microscopias Avanzadas Universidad de ZaragozaSaragossa 50018Spain Fraunhofer Research Institution for Materials Recycling and Resource Strategies IWKS Hanau 63457Germany

The thermoelectric transport properties of Zr0.43Hf0.57 NiSn half-Heusler compounds were investigated for samples sintered with different spark plasma sintering(SPS)periods:8,32 and 72 *** means of scanning transmission electron microscopy with a highangular annular dark-field detector(STEM-HAADF),it was found that sintering time affected the defect concentration,namely the amount of Ni interstitial atoms,and created locally ordered inclusions of full-Heusler *** structural information,phase composition and electrical transport properties could be consistently explained by the assumption that Ni interstitials give rise to an impurity band situated about 100 meV below the bottom of the conduction band via a self-doping *** impurity band was found to merge with the conduction band for the sample with intermediate SPS *** effect was ascribed to the gradual dissolution of full-Heusler phase inclusions and production of interstitial Ni defects,which eventually vanished for the sample with the longest sintering *** was demonstrated that the modification of the density of states near the edge of the conduction band and enhanced overall charge carrier concentration provided by defect engineering led to overall 26%increase in the thermoelectric figure of merit(ZT)with respect to the other samples.

关键词： Thermoelectric Half-Heusler Interstitial Defect engineering

bone disorders in experimentally induced liver disease in growing rats

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World Journal of gastroenterology 2005年第45期11卷 7169-7173页

作者： Viktória Ferencz Csaba Horváth béla Kári János gaál Szilvia Mészáros Zsuzsanna Wolf Dalma Heged(?)s Andrea Horváth Anikó Folhoffer Ferenc Szalay 1st Department of Internal Medicine Department of Diagnostic Radiology and Oncotherapy Department of Polymer Engineering and Textile Technology

AIM： To investigate the change of bone parameters in a new model of experimentally induced liver cirrhosis and hepatocellular carcinoma （HCC） in growing rats. METHODS： Fischer-344 rats （n = 55） were used. Carbon tetrachloride （CCh）, phenobarbital （Pb）, and a single diethylnitrosamine （DEN） injection were used. Animals were killed at wk 8 and 16. bone mineral content, femoral length, cortical index （quotient of cortical thickness and whole diameter） and ultimate bending load （Fmax） of the femora were determined. The results in animals treated with DEN＋Pb＋CCh （DPC, n = 21） were com- pared to those in untreated animals （UNT, n = 14） and in control group treated only with DEN＋Pb （DP, n = 20）. RESULTS： Fatty liver and cirrhosis developed in each DPC-treated rat at wk 8 and HCC was presented at wk 16. No skeletal changes were found in this group at wk 8, but each parameter was lower （P〈0.05 for each） at wk 16 in comparison to the control group. Neither fatty liver nor cirrhosis was observed in DP-treated animals at any time point. Femoral length and Fmax values were higher （P〈0.05 for both） in DP-treated animals at wk 8 compared to the UNT controls. However, no difference was found at wk 16. CONCLUSION： Experimental liver cirrhosis and HCC are accompanied with inhibited skeletal growth, reduced bone mass, and decreased mechanical resistance in growing rats. Our results are in concordance withthe data of other studies using different animal models. A novel finding is the transiently accelerated skeletal growth and bone strength after a 8-wk long phenobarbital treatment following diethylnitrosamine injection.

关键词： bone disorder bone mineral content Mechanical resistance Experimental liver cirrhosis Growingrat

水介质中_(C60)纳米晶体颗粒的扩散状态对其光化学反应活性的影响研究

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环境化学 2011年第9期30卷 1533-1538页

作者：倪明张波何义亮 Kim Jae-kong hughes Joeseph b 上海交通大学环境科学与工程学院上海200240 School of Civil and Environmental Engineering Georgia Institute of Technology

研究了阳离子表面活性剂CTAb,阴离子表面活性剂SDS和非离子表面活性剂TX-100和TX-405对水介质中C60纳米晶体颗粒的光化学反应活性诱导效应.结果表明,在阳离子表面活性剂CTAb、阴离子表面活性剂SDS和非离子表面活性剂TX-405中,C60纳米晶... 详细信息

研究了阳离子表面活性剂CTAb,阴离子表面活性剂SDS和非离子表面活性剂TX-100和TX-405对水介质中C60纳米晶体颗粒的光化学反应活性诱导效应.结果表明,在阳离子表面活性剂CTAb、阴离子表面活性剂SDS和非离子表面活性剂TX-405中,C60纳米晶体颗粒没有显示明显的光化学反应活性,而非离子表面活性剂TX-100能够明显诱导C60的光化学反应活性.紫外-可见吸收光谱、DLS分析和TEM成像都表明,在TX-100溶液中,C60从聚集状态向分子状态转变,尺寸变小,因而恢复其分子态C60的光化学反应活性.

关键词： C60纳米晶体颗粒扩散状态光化学反应活性

Texture development and grain boundary phase formation in Ce-and Ce-La-substituted Nd-Fe-b magnets during hot-deformation process

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Journal of Materials Science & Technology 2022年第31期126卷 71-79页

作者： ga.yeong Kim Tae-Hoon Kim Hee-Ryoung Cha Sang-hyub Lee Dong-Hwan Kim yang-Do Kim Jung-Goo Lee Department of Magnetic Materials Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Engineering Pusan National UniversityBusan 46241Republic of Korea R&D Center Star Group Ind.Co.Ltd.Daegu 42714Republic of Korea

In this study,the influence of Ce-and Ce-La-substitution for Nd in Nd-Fe-b magnets on their magnetic and microstructural changes in the course of the hot-deformation process was investigated to gain insight into further reducing the Nd content in fine-grained Nd-Fe-b hot-deformed *** found that the[001]texture and microstructure of the RE-rich grain boundary phases,which are the factors that de-termine the remanence and coercivity of hot-deformed magnets,were deteriorated by the Ce-and *** is because the volume fraction of the RE-rich liquid formed in the grain boundaries during the hot-press and hot-deformation decreased due to the Ce-and Ce-La-substitution,thereby in-creasing the friction between the 2:14:1 grains while the c-axes of grains were aligned by grain rotation and decreasing the RE concentration of grain boundary *** particular,the Ce-La-co-substitution further prevented the liquid formation within the grain boundaries of the magnets during hot-press and hot-deformation because the wettability of the RE-rich liquid on the 2:14:1 grains became poor when La was substituted for Nd in the 2:14:1 *** results indicate that there is room for further im-provement in both the remanence and coercivity of the Ce-and Ce-La-substituted magnets by intro-ducing additional liquid into the grain boundaries prior to hot-press and *** applying the Nd-Cu infiltration process to the melt-spun ribbons(intermediate infiltration,I-infiltration),both the remanence and coercivity of the Nd-saving(Nd 0.7 Ce 0.3)-Fe-b and(Nd 0.7 Ce 0.225 La 0.075)-Fe-b hot-deformed magnets were successfully improved.

关键词： Nd-Fe-b magnets Hot-deformation Nd-saving Ce-substitution La-substitution Infiltration

Effects of antibacterial compounds produced by Saccharomyces cerevisiae in Koumiss on pathogenic Escherichia coli O8 and its cell surface characteristics

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Journal of Integrative Agriculture 2017年第3期16卷 742-748页

作者： CHEN yu-jie WANG Chun-jie HOU Wen-qian WANG Xiao-shuo gaLI bing-ga HUASAI Si-mu-jide yANG Si-qin WU A-qi-ma ZHAO yu-fei WU ying-ga CHEN Ao-ri-ge-le Vocational and Technical College Inner Mongolia Agricultural University Baotou 014109 P.R. China College of Animal Science Inner Mongolia Agricultural university Hohhot 010018 P.R. China College of Veterinary Medicine Inner Mongolia Agricultural University Hohhot 010018 P.R. China

The effects of antibacterial compounds produced by Saccharomyces cerevisiae in Koumiss on pathogenic Escherichia coli O8 and its cell surface characteristics were *** isolated from Koumiss produced antibacterial compounds which were active against pathogenic *** O8 as determined by the Oxford cup *** aqueous phases from *** at p H=2.0（S2）and pH=8.0（S8）were extracted and tested,*** organic acids of S2 and S8 were determined by high performance liquid chromatography（HPLC）,and the concentrations of killer toxins were determined by enhanced bicinchoninic acid（bCA）Protein Assay *** minimum inhibition concentration（MIC）and the minimum bactericidal concentration（MbC）of S2 and S8 on *** O8 were determined by the broth microdilution *** effects of S2 and S8 on the growth curve of *** O8 were determined by turbidimetry,and the hydrophobicities of *** O8 cell surface were determined using the microbial adhesion to solvents method,the permeation of *** O8 cell membrane were determined by the o-nitrophenyl-β-D-galactoside（ONPG）*** phases at pH 2.0 and 8.0had larger inhibition zones and then S2 and S8 were obtained by *** main component in S2 was citric acid and it was propanoic acid in *** organic acids and killer toxins were also *** the MICs of S2 and S8 on *** O8 were 0.025 g m L^-1,the MbCs were 0.100 and 0.200 g m L^-1,*** normal growth curve of *** O8was S-shaped,however,it changed after addition of S2 and *** O8 was the basic character,and had a relatively hydrophilic *** hydrophobicity of *** O8 cell surface and the permeation of *** O8 cell membrane were increased after adding S2 and *** present study showed that S2 and S8 inhibit the growth of pathogenic *** O8and influence its cell surface characteristics.

关键词： antibacterial compound Saccharomyces cerevisiae Escherichia coil hydrophobicity permeation

Electrical and dielectric properties of Ni_(0.5)Co_(0.5)ga_(x)Fe_(1.8-x)O_(4)(x≤1.0)spinel ferrite microspheres

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Journal of Rare Earths 2023年第2期41卷 259-267页

作者： S.Akhtar M.A.Almessiere b.Unal A.Demir Korkmaz y.Slimani N.Tashkandi A.baykal A.Ul-Hamid A.Manikandan Department of biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Institute of Forensic Sciences and Legal Medicine Istanbul University-CerrahpasaBuyukcekmece CampusBuyukcekmece-Istanbul34500Turkey Department of Chemistry Istanbul Medeniyet UniversityUskudar/Istanbul34700Turkey Department of Nanomedicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Core Research Facilities King Fahd University of Petroleum&MineralsDhahran13261Saudi Arabia Department of Chemistry Bharath Institute of Higher Education and Research(BIHER)Bharath UniversityChennaiTamil Nadu600073India Center for Catalysis and Renewable Energy Bharath Institute of Higher Education and Research(BIHER)ChennaiTamil Nadu600073India

Microspheres of Ni_(0.5)Co_(0.5)ga_(x)Fe_(2-x)O_(4)(x≤1.0)microsphere spinel ferrites(NiCogaFe-MSFs)and carbon spheres were prepared via a hydrothermal *** micro structure of microspheres was investigated through scanning and transmission electron microscopy(SEM and TEM),respectively,and X-ray diffraction(XRD).The electrical and dielectric properties of NiCogaFe-MSF at temperatures ranging from20 to 120℃(between 293,1×10^(3)and 393.1×10^(3))for f≤3.0 MHz were systematically studied as a result of 3D graphical drawing of the data obtained from an impedance *** parameters such as ac/dc conductivity,dielectric loss,dielectric constant,activation energy,dissipation factor and Cole-Cole impedance spectra were extensively evaluated for various ga ion mole ratios in the substitution where x≤*** notice that the ac conductivity mostly obeys exponential power law rules,which vary significantly with the substitution ratios of ga *** analyses confirm that differences in conduction mechanisms in NiCogaFe-MSFs are mainly due to grain-to-grain boundaries related to ga ion substitution *** change in dielectric constant of NiCogaFe-MSFs is strongly dependent on the substitution rates and results in a normal dielectric distribution with *** tangential loss for all micro spheres is observed to vary with measured temperatures and their frequency dependencies can be attributed to the conduction mechanism similar to Koop’s phenomenological *** is clearly seen that the formation of semicircles is dominated by all the NiCogaFe-MSFs and the diameter of the semicircles mostly decreases with increasing temperature,as evidence of a temperaturedependent relaxation mechanism.

关键词： Spinel ferrites Microspheres Electrical properties Ac/dc conductivity Dielectric properties Rare earths

Corrosion by a Heavy Metal Oxide Glass

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Journal of Materials Science & Technology 2005年第2期21卷 243-245页

作者： b.b.Rana Department of Engineering Materials University of Sheffield Sheffield S1 4DU UK PCSIR Laboratories Complex LahorePakistan

Melts of lead bismuth gallate compositions are highly corrosive and attack on crucibles of different materials. In the present study, corrosion by a base glass (50PbO-30bi2O3-20ga2O3 in mole fraction) melted using different crucibles and the effect on UV-VIS and IR edges were studied. by melting the base glass in platinum/2% rhodium, gold zirconia and alumina crucibles showed less effect on the IR edge and therefore shifted the infrared edge to longer wavelength, whereas silica crucible contaminated the glass, causing a severe deterioration in the infrared and hence shifted infrared edge to much shorter wavelength. In the UV-VIS region, base glass melted in platinum/2% rhodium crucible shifted the edge to the longest wavelength whereas silica crucible shifted the edge to shorter wavelength. The contaminants from gold, zirconia and alumina crucibles caused the UV-VIS edge of the base glass to lie between the two extremes of Pt/2% Rh and SiO2 crucibles. The glasses melted in above mentioned crucibles were also characterized with inductively coupled plasma spectroscopy (ICP) analysis to measure the level of contamination from the crucibles. Depending upon crucible used, the colors of glasses obtained ranged from red to yellow.

关键词： Oxide glass Corrosion Crucible

Remarks on Thurston's Construction of Pseudo-Anosov Maps of Riemann Surfaces

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Chinese Annals of Mathematics,Series b 2008年第1期29卷 85-94页

作者： Chaohui ZHANG Department of Mathematical Sciences Morehouse College Atlanta GA 30314 USA

It is well known that certain isotopy classes of oseudo-Anosov maos on a Riemann surface S of non-excluded type can be defined through Dehn twists tα and tβ along simple closed geodesics α and β on S,respectively. Let G be the corresponding Fuchsian group acting on the hyperbolic plane H so that H/G≌*** any point α∈S,define S = S／{α}.In this article, the author gives explicit parabolic elements of G from which he constructs pseudo-Anosov classes on S that can be projected to a given pseudo-Anosov class on S obtained from Thurston＇s construction.

关键词： Quasiconformal mappings Riemann surfaces Teichmüller spaces Mapping classes Dehn twists Pseudo-Anosov bers fiber spaces