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Unity and Diversity of Responses to Xenobiotics in Organisms

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Biomedical and Environmental Sciences 1993年第4期6卷 352-366页

作者： pOONAMKAKKAR FARHATN.JAFFERY p.N.VISWANATHAN Ecotoxicology EcotoxicologyEcotoxicology SectionIndustrial Toxicology Research Centre P.O.Box 80M.G.MargLucknow-226001IndiaSectionIndustrial Toxicology Research Centre P.O.Box 80M.G.MargLucknow-226001IndiaSectionIndustrial Toxicology Research Centre P.O.Box 80M.G.MargLucknow-226001India

A conceptual treatment of the mechanisms involved in the process of toxicosis by diverse agents in different tissues indicate a likely unspecific, common, central process in addition to specific precipitating factors acting on a particular site in a cascade of events. Free radicals, membrane functions and calcium functions appear to be links in the common pathway. Such a central mechanism could be interrelated with immunological defenses as well as genotoxic changes at different sites, suggesting parallel or related evolution of these antistress mechanisms. Many radical scavengers, antioxidants, membrane stabilizers, nutritional supplements and calcium modulators have proved beneficial either in reducing toxic impact, delaying the development of lesions or even reversing the effects. Similarly, recent evidences show that some immunomodulators can act as antioxidants and antigenotoxicants. Thus, the status of body defenses which may vary from one individual to the other have a role in deciding the effects under the same quantified risks with varying relative responses. Whether modulation of physiological defenses against stress could help in developing prophylactic measures remains an open question.

关键词： Unity and Diversity of Responses to Xenobiotics in Organisms

New methods for identification of disinfection byproducts of toxicological relevance: progress and future directions

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Journal of Environmental Sciences 2021年第1期33卷 151-159页

作者： Nicholas J.p.Wawryk Caley B.Craven Lindsay K.Jmaiff Blackstock Xing-Fang Li Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonABT6G 2G3Canada

Disinfection byproducts(DBps)represent a ubiquitous source of chemical exposure in disinfected *** over 700 DBps have been identified,the drivers of toxicity remain poorly ***,ever evolving water treatment practices have led to a continually growing list of *** of analytical technologies have enabled the identification of new classes of DBps and the quantification of these chemically diverse sets of *** we summarize advances in new workflows for DBp analysis,including sample preparation,chromatographic separation with mass spectrometry(MS)detection,and data *** aid in the selection of techniques for future studies,we discuss necessary considerations for each step in the *** review focuses on how each step of a workflow can be optimized to capture diverse classes of DBps within a single ***,we highlight new MS-based approaches that can be powerful for identifying novel DBps of toxicological *** discuss current challenges and provide perspectives on future research directions with respect to studying new DBps of toxicological *** analytical technologies continue to advance,new strategies will be increasingly used to analyze complex DBps produced in different treatment processes with the aim to identify potential drivers of toxicity.

关键词： Water disinfection byproducts(DBps) Emerging contaminants Mass spectrometry Chromatography Nontargeted analysis Toxicity drivers

Melatonin prevents oxidative stress,inflammatory activity,and DNA damage in cirrhotic rats

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World Journal of Gastroenterology 2022年第3期28卷 348-364页

作者： Josieli R Colares Renata M Hartmann Elizângela G Schemitt Sandielly R B Fonseca Marilda S Brasil Jaqueline N picada Alexandre S Dias Aline F Bueno Cláudio A Marroni Norma p Marroni Medical Sciences program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil Marilda S BrasilNorma Biological Sciences program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil Cellular and Molecular Biology program Lutheran University of Brazil(ULBRA)Canoas 92425-900Brazil pneumological Sciences program Universidade Federal do Rio Grande do SulPorto Alegre 90050-170Brazil posgraduate program in Hepatology Universidade Federal de Ciências da Saúde de Porto AlegrePorto Alegre 90050-170Brazil

BACKGROUND Cirrhosis is an important health problem characterized by a significant change in liver *** animals,this can be reproduced by an experimental model of bile duct ligation(BDL).Melatonin(MLT)is a physiological hormone synthesized from serotonin that has been studied for its beneficial properties,including its antioxidant *** To evaluate MLT’s effects on oxidative stress,the inflammatory process,and DNA damage in an experimental model of secondary biliary *** Male Wistar rats were divided into 4 groups:Control(CO),CO+MLT,BDL,and BDL+*** was administered(20 mg/kg)daily beginning on day 15 after biliary *** day 29 the animals were *** samples,liver tissue,and bone marrow were collected for further *** BDL caused changes in biochemical and histological parameters and markers of inflammatory *** acid(0.46±0.01)reactive substance levels,superoxide dismutase activity(2.30±0.07)and nitric oxide levels(2.48±0.36)were significantly lower(pps that received *** damage was also lower(pps(171.6±32.9)than the BDL-only group(295.5±34.8).Tissue damage and the expression of nuclear factor kappa B,interleukin-1β,Nrf2,NQO1 and Hsp70 were significantly lower in animals treated with MLT(pparameters.

关键词： Antioxidants Secondary biliary cirrhosis Oxidative stress Melatonin Bile duct ligation

Reliable folding of hybrid tetrapeptides into shortβ-hairpins

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Chinese Chemical Letters 2022年第1期33卷 257-261页

作者： Xue-Yi Sun Yulong Zhong Yao-Hua Li Daniel p.Miller Sagar Buttan Xiang-Xiang Wu Yukun Zhang Quan Tang Hong-Wei Tan Jin Zhu Rui Liu Eva Zurek Zhong-Lin Lu Bing Gong College of Chemistry Beijing Normal UniversityBeijing 100875China Department of Chemistry University at BuffaloThe State University of New YorkBuffaloNY 14260United States Department of Chemistry Hofstra UniversityHempsteadNY 11549United States Academy of Chinese Medical Science Henan University of Chinese MedicineZhengzhou 450046China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China

Five hybrid tetrapeptides,each consisting a central dipeptide segment ofα-amino acid residues flanked by two aromaticγ-amino acid residues,are found to fold into well-definedβ-hairpin conformations as shown by NMR,computational study,and X-ray *** turn loop of thisβ-hairpin motif accommodates different two-residueα-amino acid sequences from the highly flexible Gly-Gly,to the more restricted *** presence ofα-amino acid side chains enhances the stabilities of theβ-hairpins with the exception of D-pro-Gly-which results in *** on this hairpin/turn motif,a variety of different dipeptide sequences ofα-amino acids which rarely occur inβ-turns can be introduced and presented as two-residue loops.

关键词： β-Hairpin β-Turn γ-Amino acid NMR X-ray

Development of cost effective personnel armour through structural hybridization

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Defence Technology（防务技术） 2020年第6期16卷 1089-1097页

作者： p.Rama Subba Reddy T.Sreekantha Reddy I.Srikanth Juhi Kushwaha V.Madhu Defence Metallurgical Research Laboratory Hyderabad500058India Advanced Systems Laboratory Hyderabad500058India

The objective of the present study is to develop cost effective thermoplastic hybrid laminate using Dyneema®HB50 and Tensylon®HSBD 30A through structural hybridization *** having 20 mm thickness were fabricated and subjected to 7.6239 mm mild steel core projectile with an impact velocity of 730±10 ms*** such as energy absorption,back face deformation and rate of back face deformation were measured as a function of hybridization *** was observed that hybrid laminate with 50:50 ratio(w/w)of Tensylon®and Dyneema®with Tensylon®as front face showed 200%more energy absorption when compared to 100%Tensylon®laminate and showed equal energy absorption as that of expensive 100%Dyneema®***,hybrid laminate with TD50:50 ratio showed 40%lower in terms of final back face deformation than Dyneema®*** of back face deformation was also found to be slow for hybrid laminate as compared to Dyneema®*** mechanical analysis showed that,Tensylon®laminate has got higher stiffness and lower damping factor than Dyneema®and hybrid *** interface between Tensylon®and Dyneema®layers was found to be separating during the penetration process due to the poor interfacial *** behaviour of laminates for different hybridization ratios were studied by sectioning the impacted *** was observed that,the Tensylon®laminate has undergone shear cutting of fibers as major failure mode whereas the hybrid laminate showed shear cutting followed by tensile stretching,fiber pull out and *** inputs are highly useful for body armour applications to design cost effective armour with enhanced performance.

关键词： Dyneema® Tensylon® Hybrid laminate Ballistic impact Energy absorption Back face signature

A practical model for efficient anti-fatigue design and selection of metallic materials:Ⅰ.Model building and fatigue strength prediction

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Journal of Materials Science & Technology 2021年第11期70卷 233-249页

作者： R.Liu p.Zhang Z.J.Zhang B.Wang Z.F.Zhang Laboratory of Fatigue and Fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsInstitute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

The high cost and low efficiency of fatigue tests are bottleneck problem for the anti-fatigue design of metallic *** this problem,a theoretical fatigue model is proposed in this study,the possible applications have also been *** results would be introduced in two serial papers,in which the first paper focuses on the model building and the applications on fatigue strength prediction;the second paper put emphasis on the influencing factors of the model parameters and the applications on fatigue strength *** this first paper,a theoretical model is proposed considering both the strength and plastic restrictions of fatigue *** the model builds up a brief relationship among yield strength(Y),tensile strength(T)and fatigue strength(F),it is named as the Y-T-F *** the verification with fatigue strength data covering various kinds of metallic materials and loading conditions,this Y-T-F model exhibits both generality and *** the Y-T-F model,the efficient fatigue strength prediction could be conducted by brief linear fitting and calculation,just through yield strength,tensile strength and several known fatigue strength ***,through its deduced Y-F model,the analytical formula of fatigue strength continuously changing with materials strengthening can be obtained,as well as the maximum value of fatigue strength and corresponding critical yield *** summary,the Y-T-F model would be useful for reducing the fatigue tests,thus providing new possibilities on the efficient anti-fatigue design and selection of metallic materials.

关键词： Yield strength Tensile strength plasticity Fatigue strength Anti-fatigue design

Differential fate of metabolism of a disperse dye by microorganisms Galactomyces geotrichum and Brevibacillus laterosporus and their consortium GG-BL

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Journal of Environmental Sciences 2012年第7期24卷 1295-1304页

作者： Tatoba R.Waghmode Mayur B.Kurade Anuradha N.Kagalkar Sanjay p.Govindwar Department of Biochemistry Shivaji University Department of Biotechnology Shivaji University

The present work aims to evaluate Brown 3 REL degrading potential of developed microbial consortium GG-BL using two microbial cultures, Galactomyces geotrichum MTCC 1360 （GG） and BrevibaciUus laterosporus MTCC 2298 （BL）. Microbial consortium GG-BL showed 100% decolorization of a dye Brown 3 REL, while individually G. geotrichum MTCC 1360 and B. laterosporus MTCC 2298 showed 26% and 86% decolorization under aerobic condition （shaking） respectively. Measurements of biochemical oxygen demand （BOD）（76%） and chemical oxygen demand （COD）（68%） were done after decolorization by consortium GG-BL. No induction in activities of oxidoreductive enzymes found in G. geotrichum while B. laterosporus showed induction of veratryl alcohol oxidase, Nicotineamide adenine dinucleotide-dichlorophenol indophenol （NADH-DCIp） reductase and riboflavin reductase indicating their role in dye metabolism. Consortium GG-BL showed induction in the activities of laccase, veratryl alcohol oxidase, tyrosinase, NADH-DCIp reductase and riboflavin reductase. Two different sets of induced enzymes from G. geotrichum and B. laterosporus work together in consortium GG-BL resulting in faster degradation of dye. The degradation of Brown 3 REL was analyzed using high performance thin layer chromatography （HpTLC）, high performance liquid chromatography （HpLC）, Fourier transform infrared spectroscopy （FT-IR） and gas chromatography mass spectroscopy （GC-MS）. phytotoxicity study revealed that metabolites formed after degradation was significantly less toxic in nature.

关键词： consortium GG-BL decolorization Brown 3 REL biochemical oxygen demand laccase biodegradation

In-vivo evaluation of molybdenum as bioabsorbable stent candidate

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Bioactive Materials 2022年第8期7卷 262-271页

作者： Malgorzata Sikora-Jasinska Lea M.Morath Maria p.Kwesiga Margaret E.plank Alexia L.Nelson Alexander A.Oliver Martin L.Bocks Roger J.Guillory II Jeremy Goldman Department of Biomedical Engineering Michigan Technological UniversityUSA Department of Biomedical Engineering and physiology Mayo Clinic Graduate School of Biomedical SciencesUSA Case Western Reserve University School of Medicine UH Rainbow Babies&Children’s HospitalClevelandOHUSA

Biodegradable stents have tremendous theoretical potential as an alternative to bare metal stents and drug-eluting stents for the treatment of obstructive coronary artery *** bioresorbable or biodegradable scaffold material needs to possess optimal mechanical properties and uniform degradation behavior that avoids local and systemic ***,molybdenum(Mo)has been investigated as a potential novel biodegradable material for this *** its proven moderate degradation rate and excellent mechanical properties,Mo may represent an ideal source material for clinical cardiac and vascular *** present study was performed to evaluate the mechanical performance of metallic Mo in vitro and the biodegradation properties in *** results demonstrated favorable mechanical behavior and a uniform degradation profile as desired for a new generation ultra-thin degradable endovascular stent ***,Mo implants in mouse arteries avoided the typical cellular response that contributes to *** was minimal neointimal hyperplasia over 6 months,an absence of excessive smooth muscle cell(SMC)proliferation or inflammation near the implant,and avoidance of significant harm to regenerating endothelial cells(EC).Qualitative inspection of kidney sections showed a potentially pathological remodeling of kidney Bowman’s capsule and glomeruli,indicative of impaired filtering function and development of kidney disease,although quantifications of these morphological changes were not statistically ***,the results suggest that the products of Mo corrosion may exert beneficial or inert effects on the activities of inflammatory and arterial cells,while exerting potentially toxic effects in the kidneys that warrant further investigation.

关键词： Biodegradable stent Molybdenum Biocompatibility Degradation

Diagnostic Classification of Normal persons andCancer patients by Using Neural NetworkBased on Trace Metal Contents in Serum Samples

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Chemical Research in Chinese Universities 2001年第2期17卷 153-158页

作者： ZHANG Zhuo-yong, HONG Zhe, ZHOU Hua-lan and LIU Si-dong (Faculty of Chemistry, Northeast Normal University, Changchun 130024, p. R. China Chemical Engineering Department, Dandong College, Dandong 118003, p. R. China) 东北师范大学吉林长春 130024 丹东职业技术学院辽宁丹东 118003

Artificial neural network with the back-propagation (Bp-ANN) approach was applied to the classification of normal persons and various cancer patients based on the elemental contents in serum samples. This method was verified by the cross-validation method. The effects of the net- work parameters were investigated and the related problems were discussed. The samples of 72, 42, and 52 for lung, liver, and stomach cancer patients and normal persons, respectively, were used for the classification study. About 95% of the samples can be classified correctly. There- fore, the method can be used as an auxiliary means of the diagnosis of cancer.

关键词： Artificial neural network Classification Trace element Cancer