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Effects of aminoguanidine on nitric oxide production induced by inflammatory cytokines and endotoxin in cultured rat hepatocytes 被引量:20
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作者 Guo Liang Zhang Ye Hong Wang Hui Ling Teng Zhi Bin Lin Department of Pharmacology,School of Basic Medical Sciences,Beijing University,Beijiog 100083,ChinaDr.Guo Liang Zhang graduated from Xinxiang Medical College in 1982,got Ph.D.at Nagoya City University Medical School,Japan in 1994,finished postdoctoral research at Beijing Medical Univcrsity in 1996,now an associate professor of pharmacology,specialized in hepatic pharmacology,having 15 papers published. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期331-334,共4页
AIM: To study the effects of aminoguanidine (AG) and two L-arginine analogues N(omega)-nitro-L-arginine methyl ester (L-NAME) and N(omega)-nitro-L-arginine (L-NNA) on nitric oxide (NO) production induced by cytokines ... AIM: To study the effects of aminoguanidine (AG) and two L-arginine analogues N(omega)-nitro-L-arginine methyl ester (L-NAME) and N(omega)-nitro-L-arginine (L-NNA) on nitric oxide (NO) production induced by cytokines (TNF-alpha, IL-1 beta, and IFN-gamma) and bacterial lipopolysaccharide (LPS) mixture (CM) in the cultured rat hepatocytes, and examine their mechanisms action. METHODS: Rat hepatocytes were incubated with AG, L-NAME, L-NNA, Actinomycin D (ActD) and dexamethasone in a medium containing CM (LPS plus TNF-alpha, IL-1 beta, and IFN-gamma) for 24h. NO production in the cultured supernatant was measured with the Griess reaction. Intracellular cGMP level was detected with radioimmunoassy. RESULTS: NO production was markedly blocked by AG and L-NAME in a dose-dependent manner under inflammatory stimuli condition triggered by CM in vitro. The rate of the maximum inhibitory effects of L-NAME (38.9%) was less potent than that obtained with AG(53.7%, P 【 0.05). There was no significant difference between the inhibitory effects of AG and two L-arginine analogues on intracellular cGMP accumulation in rat cultured hepatocytes. Non-specific NOS expression inhibitor dexamethasone (DEX)and iNOS mRNA transcriptional inhibitor ActD also significantly inhibited CM-induced NO production. AG(0.1 mmol x L(-1)) and ActD (0.2 ng x L(-1)) were equipotent in decreasing NO production induced by inflammatory stimuli in vitro, and both effects were more potent than that induced by non-selectivity NOS activity inhibitor L-NAME (0.1 mmol x L(-1)) under similar stimuli conditions (P【0.01). CONCLUSION: AG is a potent selective inhibitor of inducible isoform of NOS,and the mechanism of action may be not only competitive inhibition in the substrate level, but also the gene expression level in rat hepatocytes. 展开更多
关键词 Animals Antineoplastic Agents Cells Cultured Comparative Study Cyclic GMP Cytokines DACTINOMYCIN Dexamethasone Enzyme Inhibitors Glucocorticoids GUANIDINES Hepatocytes Interferon Type II INTERLEUKIN-1 LIPOPOLYSACCHARIDES Male NG-Nitroarginine Methyl Ester Nitric oxide Nitric oxide Synthase inhibitors Nitroarginine Protein Synthesis Inhibitors RATS Rats Wistar Research Support Non-U.S. Gov't Tumor Necrosis Factor-alpha
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Oxidation Kinetics of Aluminum Powders in a Gas Fluidized Bed Reactor in the Potential Application of Surge Arresting Materials
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作者 Hong Shih 《Materials Sciences and Applications》 2019年第3期253-292,共40页
In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arre... In this technical paper, the oxidation mechanism and kinetics of aluminum powders are discussed in great details. The potential applications of spherical aluminum powders after oxidation to be part of the surging arresting materials are discussed. Theoretical calculations of oxidation of spherical aluminum powders in a typical gas fluidization bed are demonstrated. Computer software written by the author is used to carry out the basic calculations of important parameters of a gas fluidization bed at different temperatures. A mathematical model of the dynamic system in a gas fluidization bed is developed and the analytical solution is obtained. The mathematical model can be used to estimate aluminum oxide thickness at a defined temperature. The mathematical model created in this study is evaluated and confirmed consistently with the experimental results on a gas fluidization bed. Detail technical discussion of the oxidation mechanism of aluminum is carried out. The mathematical deviations of the mathematical modeling have demonstrated in great details. This mathematical model developed in this study and validated with experimental results can bring a great value for the quantitative analysis of a gas fluidization bed in general from a theoretical point of view. It can be applied for the oxidation not only for aluminum spherical powders, but also for other spherical metal powders. The mathematical model developed can further enhance the applications of gas fluidization technology. In addition to the development of mathematical modeling of a gas fluidization bed reactor, the formation of oxide film through diffusion on both planar and spherical aluminum surfaces is analyzed through a thorough mathematical deviation using diffusion theory and Laplace transformation. The dominant defects and their impact to oxidation of aluminum are also discussed in detail. The well-controlled oxidation film on spherical metal powders such as aluminum and other metal spherical powders can potentially become an important part of switch devices of surge arresting materials, in general. 展开更多
关键词 Aluminum Spherical Power GAS FLUIDIZATION Bed Oxidation Mechanism oxide Growth Rate Gibbs Free Energy Ellingham Diagram Mathematical Modeling Dynamic System Plasma DIFFUSION DIFFUSION Coefficient Crystallographic Defect Vacancy Pressure Temperature Flow Laplace Transform Equation Boundary Condition Ficks Second Law Software Experimental Theoretical SURGE ARRESTING MATERIALS Analytical Solution
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Phase composition,conductivity,and sensor properties of cerium-doped indium oxide
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作者 M.I.Ikim G.N.Gerasimov +2 位作者 V.F.Gromov O.J.Ilegbusi L.I.Trakhtenberg 《Nano Materials Science》 EI CAS CSCD 2024年第2期193-200,共8页
The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these compounds.During the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)... The hydrothermal synthesis of In_(2)O_(3)and CeO_(2)–In_(2)O_(3)is investigated as well as the properties of sensor layers based on these compounds.During the synthesis of In_(2)O_(3),intermediate products In(OH)_(3)and InOOH are formed,which are the precursors of stable cubic(c-In_(2)O_(3))and metastable rhombohedral(rh-In_(2)O_(3))phases,respectively.A transition from c-In_(2)O_(3)to rh-In_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-In_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-In_(2)O_(3).The data on the sensor activity of the composites correlate with XPS results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-In_(2)O_(3).The reverse situation is observed in composites based on c-In_(2)O_(3).Compared to In_(2)O_(3)and CeO_(2)–In_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between In_(2)O_(3)and CeO_(2). 展开更多
关键词 Cerium oxide Indium oxide NANOCOMPOSITE Hydrothermal method Cubic phase Rhombohedral phase Sensor response CONDUCTIVITY HYDROGEN Response/recovery time
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Molecular Dynamics, Physical Properties, Diffusion Coefficients and Activation Energy of the Lithium Oxide (Li-O) and Sodium Oxide (Na-O) Electrolyte (Cathode)
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作者 Alain Second Dzabana Honguelet Abel Dominique Eboungabeka Timothée Nsongo 《Advances in Materials Physics and Chemistry》 CAS 2024年第9期213-234,共22页
This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied ... This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied a gap-free model using molecular dynamics. Physical quantities such as volume and pressure of the Na-O and Li-O systems exhibit similar behaviors around the thermodynamic ensembles NPT and NVE. However, for the Na2O system, at a minimum temperature value, we observe a range of total energy values;in contrast, for the Li2O system, a minimum energy corresponds to a range of temperatures. Finally, for physicochemical properties, we studied the diffusion coefficient and activation energy of lithium and potassium oxides around their melting temperatures. The order of magnitude of the diffusion coefficients is given by the relation Dli-O >DNa-O for the multiplicity 8*8*8, while for the activation energy, the order is well reversed EaNa-O > EaLi-O. 展开更多
关键词 Molecular Dynamics Diffusion Coefficients Activation Energy Lithium oxide Sodium oxide Lennard Jones Potential Data File Atomic and Charge Models CATHODE LAMMPS
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Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity
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作者 Riccardo Brandiele Andrea Guadagnini +9 位作者 Mattia Parnigotto Federico Pini Vito Coviello Denis Badocco Paolo Pastore Gian Andrea Rizzi Andrea Vittadini Daniel Forrer Vincenzo Amendola Christian Durante 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期508-520,共13页
The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date... The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating conditions.In this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ORR.Pt_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in liquid.The novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(<10 nm)of commercial Pt catalysts,yet resulting remarkably more active with E_(1/2)=0.943 V vs.RHE,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode. 展开更多
关键词 ELECTROCATALYSIS GDE ORR Pt_(2)Y Pt_(3)Y LAL LFL oxide support PTO NANOALLOYS
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Nitric oxide mediated Staphylococcus aureus pathogenesis and protective role of nanoconjugated vancomycin 被引量:4
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作者 Subhankari Prasad Chakraborty Santanu Kar Mahapatra +3 位作者 Sumanta Kumar Sahu Sourav Chattopadhyay Panchanan Pramanik Somenath Roy 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第2期102-109,共8页
Objective:To investigate the relation between fruit seeds,plants residuals and appendicitis. Methods:Among cases that underwent appendectomy,the appendicitis cases having fruit seeds and undigested plant residuals in ... Objective:To investigate the relation between fruit seeds,plants residuals and appendicitis. Methods:Among cases that underwent appendectomy,the appendicitis cases having fruit seeds and undigested plant residuals in their etiology were examined retrospectively.Also, histopathological features,age,sex,and parameters of morbidity and mortality were used. Results:Fruit seed was found in one case(0.05%) with presence of pus in appendix lumen, undigested plant residuals in 7 cases(0.35%).It was determined that there were appendix inflammation in 2 of the plant residuals cases,while there were obstruction and lymphoid hyperplasia in the appendix lumen of 5 cases.No mortality was observed.Conclusions:The ratio of acute appendicitis caused by plants is minimal among all appendectomised patients, but avoidence of eating undigested fruit seeds and chewing plants well may help to prevent appendicitis. 展开更多
关键词 STAPHYLOCOCCUS AUREUS Lymphocyte Nanoconjugated VANCOMYCIN Antioxidant enzymes TNF-α IL-10 Infection Anti-inflammatory ANTIOXIDATIVE effect BACTEREMIA Oxidative stress Nitric oxide Inflammatory parameter PATHOGENESIS
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New insights on the pathogenesis of pyloric stenosis of infancy. A review with emphasis on the hyperacidity theory 被引量:1
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作者 Ian M. Rogers 《Open Journal of Pediatrics》 2012年第2期97-105,共9页
A review is presented on the theories concerning the cause of pyloric stenosis with emphasis on the primary position of inherited hyperacidity in pathogenesis. Existing theories are critically analysed and the hyperac... A review is presented on the theories concerning the cause of pyloric stenosis with emphasis on the primary position of inherited hyperacidity in pathogenesis. Existing theories are critically analysed and the hyperacidity theory is precisely defined in the light of recent physiological insights into the gastrointestinal hormone motilin. The progressive fixed fasting hypergastrinaemia within the first few weeks of life will, in the baby who inherits acid secretion at the top of the normal range, produce hyperacidity of sufficient severity to trigger the process of acid-induced work hypertrophy of the pylorus. The potential contribution of motilin is discussed. The baby who inherits a normal gastric acidity will not reach acid levels severe enough to trigger sphincter hypertrophy despite the early gastrin stimulus. The potential threat will cease when gastrin naturally declines with age and the pyloric canal becomes wider. Genetic factors clearly must also be involved and these are separately discussed. 展开更多
关键词 Infantile Hypertrophic Pyloric stenosis (IHPS) Immunohistochemistry Smooth Muscle CELLS Gastrin MOTILIN Gastrointestinal MOTILITY Erythromycin PYLOROMYOTOMY Acidification of the Stomach Pyloric SPHINCTER Function Receptor Binding Pathogenesis Antral MOTILITY Gastric Outflow Obstruction Linkage Analysis Single Nucleotide Polymorphism: Interstitial CELLS of Cahal Nitric oxide Synthetase
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Association of endothelial nitric oxide synthase gene T-786C promoter polymorphism with gastric cancer 被引量:2
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作者 Devulapalli Krishnaveni Bhayal Amar Chand +6 位作者 Porika Shravan Kumar Malladi Uma Devi Macherla Ramanna Akka Jyothy Nallari Pratibha N Balakrishna Ananthapur Venkateshwari 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2015年第7期87-94,共8页
AIM: To investigate the role of endothelial nitric oxide synthase-786 T > C promoter polymorphism in the etiology of gastric cancer(GC). METHODS: A total of 150 GC patients and 150 control subjects were included in... AIM: To investigate the role of endothelial nitric oxide synthase-786 T > C promoter polymorphism in the etiology of gastric cancer(GC). METHODS: A total of 150 GC patients and 150 control subjects were included in the study. The information on demographic features was elicited with an informed consent from all the patients and control subjects using a structured questionnaire. Helicobacter pylori(H. pylori) infectivity status was tested in antral biopsies from all the subjects by rapid urease test following the method of Vaira et al. Genomic DNA was isolated from whole blood samples following the salting out method of Lahiri et al. Genotype analysis of the rs2070744 polymorphism was carried out by allele-specific polymerase chain reaction method. The genotypes were determined based on the appearance of bands on an agarose gel stained with ethidium bromide under ultraviolet gel documentation with the help of 100 bp ladder. Odds ratios and corresponding 95%CIs were determined using java stat online software. RESULTS: There was a significant difference in the distribution of C allele(C vs T; P = 0.000, OR = 5.038) in patient group compared to the control subjects exhibiting a fivefold increased risk for GC. When the T/T and C/C genotypes were compared, there was an enhanced GC risk for individuals with C/C genotype(T/T vs C/C; P = 0.000). Among the demographic factors, smoking and alcoholism were the common risk factors in patients compared to the control subjects(P < 0.05). Patients with smoking and alcoholism developed cancer even in heterozygous T/C condition(smoking: P = 0.020 and alcoholism: P = 0.005). Individuals with H. pylori infection showed seven fold increased risk for cancer. All the patients with C/C genotype revealed a significant association between H. pylori infection and GC. Among the patients 2.4% of them revealed familial incidence of GC. No significant difference was noticed between cases and controls with regard to consanguinity(P = 0.473).CONCLUSION: The Present data suggest that eN OS-786 C/C genotype and C allele may be considered as potential risk factors in patients with GC. 展开更多
关键词 Genetics HELICOBACTER PYLORI Nutrition Oncology Endoscopy Gastro DUODENAL NITRIC oxide Single NUCLEOTIDE polymorphism rs2070744 Agarosegel electrophoresis ALLELE specific polymerase chainreaction
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Design and Analysis of MEMS Based Aluminum Nitride (AlN), Lithium Niobate (LiNbO<sub>3</sub>) and Zinc Oxide (ZnO) Cantilever with Different Substrate Materials for Piezoelectric Vibration Energy Harvesters Using COMSOL Multiphysics Software
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作者 Ahmad M.Alsaad Ahmad A.Ahmad +2 位作者 Qais M.Al-Bataineh Nermeen S.Daoud Mais H.Khazaleh 《Open Journal of Applied Sciences》 2019年第4期181-197,共17页
Interest in energy harvesters has grown rapidly over the last decade. The cantilever shaped piezoelectric energy harvesting beam is one of the most employed designs, due to its simplicity and flexibility for further p... Interest in energy harvesters has grown rapidly over the last decade. The cantilever shaped piezoelectric energy harvesting beam is one of the most employed designs, due to its simplicity and flexibility for further performance enhancement. The research effort in the MEMS Piezoelectric vibration energy harvester designed using three types of cantilever materials, Lithium Niobate (LiNbO3), Aluminum Nitride (AlN) and Zinc Oxide (ZnO) with different substrate materials: aluminum, steel and silicon using COMSOL Multiphysics package were designed and analyzed. Voltage, mechanical power and electrical power versus frequency for different cantilever materials and substrates were modeled and simulated using Finite element method (FEM). The resonant frequencies of the LiNbO3/Al, AlN/Al and ZnO/Al systems were found to be 187.5 Hz, 279.5 Hz and 173.5 Hz, respectively. We found that ZnO/Al system yields optimum voltage and electrical power values of 8.2 V and 2.8 mW, respectively. For ZnO cantilever on aluminum, steel and silicon substrates, we found the resonant frequencies to be 173.5 Hz, 170 Hz and 175 Hz, respectively. Interestingly, ZnO/steel yields optimal voltage and electrical power values of 9.83 V and 4.02 mW, respectively. Furthermore, all systems were studied at different differentiate frequencies. We found that voltage and electrical power have increased as the acceleration has increased. 展开更多
关键词 MEMS PIEZOELECTRIC Energy Harvester CANTILEVER Lithium Niobate (LiNbO3) Aluminum Nitride (AlN) Zinc oxide (ZnO) Aluminium SUBSTRATE Steel SUBSTRATE Silicon SUBSTRATE COMSOL Finite Element Method
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Cycling performance of layered oxide cathode materials for sodium-ion batteries
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作者 Jinpin Wu Junhang Tian +1 位作者 Xueyi Sun Weidong Zhuang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1720-1744,共25页
Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the applicat... Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the application prospects of batteries.However,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application requirements.Therefore,this review proposes several strategies to address these challenges.First,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion doping.Second,homogeneous surface coating and concentration gradient modification are reviewed.In addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are proposed.Finally,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials. 展开更多
关键词 sodium-ion battery layered oxide materials cycling performance bulking doping surface coating concentration gradient mixed structure high-entropy
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转录因子CREB激活介导吗啡依赖SK-N-SH细胞的nNOS及fosB基因表达的调控机制 被引量:3
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作者 苏彦君 丛斌 +4 位作者 张国忠 张瑾 李淑瑾 姚玉霞 付丽红 《第三军医大学学报》 CAS CSCD 北大核心 2005年第5期395-398,共4页
目的 探讨吗啡依赖的SK- N -SH细胞表达神经元型一氧化氮合酶 (neuronalnitricoxidesynthase ,nNOS)及fosB基因的调控机制。方法 建立吗啡依赖及戒断细胞模型 ,体外合成含cAMP反应元件 (cAMPresponseelement ,CRE)序列的寡核苷酸 ,经... 目的 探讨吗啡依赖的SK- N -SH细胞表达神经元型一氧化氮合酶 (neuronalnitricoxidesynthase ,nNOS)及fosB基因的调控机制。方法 建立吗啡依赖及戒断细胞模型 ,体外合成含cAMP反应元件 (cAMPresponseelement ,CRE)序列的寡核苷酸 ,经硫代磷酸化修饰 ,作为单链寡核苷酸 (CRE transcriptionfactordecoyoligodeoxynucleotide ,CRE decoyODN)。分别采用电泳迁移率改变分析 (electrophoresismobilityshiftassay ,EMSA)及RT -PCR技术 ,检测CRE decoyODN对吗啡依赖及纳络酮急性戒断诱导的CREB的DNA结合活性、nNOS及fosBmRNA表达的影响。结果 吗啡依赖及纳络酮急性戒断使SK- N- SH细胞的CREB的DNA结合活性、nNOS及fosBmRNA明显升高 ,CRE decoyODN可特异抑制上述指标升高。结论 CREB的激活介导了吗啡依赖SK- N 展开更多
关键词 SK-N-SH NNOS CREB FOSB DNA RT-PCR nitric factor mRNA oxide decoy cAMP ODN
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The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia
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作者 Xiaorong Zhang Zhiying Chen +3 位作者 Yinyi Xiong Qin Zhou Ling-Qiang Zhu Dan Liu 《Neural Regeneration Research》 SCIE CAS 2025年第2期402-415,共14页
With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic... With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic rate.However,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia patients.Similarly in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive decline.Nitric oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous system.Recently,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular dementia.This review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular dementia.Additionally,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia. 展开更多
关键词 endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia
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Elimination of methicillin‑resistant Staphylococcus aureus biofilms on titanium implants via photothermally‑triggered nitric oxide and immunotherapy for enhanced osseointegration
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作者 Yong‑Lin Yu Jun‑Jie Wu +5 位作者 Chuan‑Chuan Lin Xian Qin Franklin R.Tay Li Miao Bai‑Long Tao Yang Jiao 《Military Medical Research》 SCIE CAS CSCD 2024年第2期157-179,共23页
Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to expl... Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to explore more effective approaches for the treatment of MRSA biofilm infections.Methods:Herein,an interfacial functionalization strategy is proposed by the integration of mesoporous polydopamine nanoparticles(PDA),nitric oxide(NO)release donor sodium nitroprusside(SNP)and osteogenic growth peptide(OGP)onto Ti implants,denoted as Ti-PDA@SNP-OGP.The physical and chemical properties of Ti-PDA@SNP-OGP were assessed by scanning electron microscopy,X-ray photoelectron spectroscope,water contact angle,photothermal property and NO release behavior.The synergistic antibacterial effect and elimination of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein diacetate probe,1-N-phenylnaphthylamine assay,adenosine triphosphate intensity,O-nitrophenyl-β-D-galactopyranoside hydrolysis activity,bicinchoninic acid leakage.Fluorescence staining,assays for alkaline phosphatase activity,collagen secretion and extracellular matrix mineralization,quantitative real‑time reverse transcription‑polymerase chain reaction,and enzyme-linked immunosorbent assay(ELISA)were used to evaluate the inflammatory response and osteogenic ability in bone marrow stromal cells(MSCs),RAW264.7 cells and their co-culture system.Giemsa staining,ELISA,micro-CT,hematoxylin and eosin,Masson's trichrome and immunohistochemistry staining were used to evaluate the eradication of MRSA biofilms,inhibition of inflammatory response,and promotion of osseointegration of Ti-PDA@SNP-OGP in vivo.Results:Ti-PDA@SNP-OGP displayed a synergistic photothermal and NO-dependent antibacterial effect against MRSA following near-infrared light(NIR)irradiation,and effectively eliminated the formed MRSA biofilms by inducing reactive oxygen species(ROS)-mediated oxidative stress,destroying bacterial membrane integrity and causing leakage of intracellular components(P<0.01).In vitro experiments revealed that Ti-PDA@SNP-OGP not only facilitated osteogenic differentiation of MSCs,but also promoted the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2-phenotype(P<0.05 or P<0.01).The favorable osteo-immune microenvironment further facilitated osteogenesis of MSCs and the anti-inflammation of RAW264.7 cells via multiple paracrine signaling pathways(P<0.01).In vivo evaluation confirmed the aforementioned results and revealed that Ti-PDA@SNP-OGP induced ameliorative osseointegration in an MRSA-infected femoral defect implantation model(P<0.01).Conclusions:Ti-PDA@SNP-OGP is a promising multi-functional material for the high-efficient treatment of MRSA infections in implant replacement surgeries. 展开更多
关键词 Polydopamine nanoparticles Methicillin-resistant Staphylococcus aureus Nitric oxide OSSEOINTEGRATION Osteo-immunomodulation Photothermal effect Titanium implants
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Expression of inducible nitric oxide synthase and cyclooxygenase-2 in pancreatic adenocarcinoma:Correlation with microvessel density 被引量:14
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作者 Hans U.Kasper Hella Wolf +2 位作者 Uta Drebber Helmut K.Wolf Michael A.Kern 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第13期1918-1922,共5页
AIM:Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins.Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible i... AIM:Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins.Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible isoforms.The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis,tumorigenesis and inflammatory processes.This study was to clarify their role in pancreatic adenocarcinomas. METHODS:We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocardnomas of different grade and stage.The results were compared with microvessel density and dinicopathological data. RESULTS:Twenty-one (52.5%) of the cases showed iNOS expression,15 (37.5%) of the cases were positive for COX-2. The immunoreaction was heterogeneously distributed within the tumors.Staining intensity was different between the tumors.No correlation between iNOS and COX-2 expression was seen.There was no relationship with microvessel density. However,iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression.There was no correlation with other clinicopathological data. CONCLUSION:Approximately half of the cases expressed iNOS and COX-2.These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas.Due to a low prevalence of COX-2 expression,chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success. 展开更多
关键词 Adenocarcinoma Aged Aged 80 and over Cyclooxygenase 2 Female Humans Immunohistochemistry ISOENZYMES Male Membrane Proteins MICROCIRCULATION Middle Aged Nitric oxide Synthase Nitric oxide Synthase Type II Pancreas Pancreatic Neoplasms Prostaglandin-Endoperoxide Synthases
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Analysis of the nitric oxide-cyclic guanosine monophosphate pathway in experimental liver cirrhosis suggests phosphodiesterase-5 as potential target to treat portal hypertension 被引量:2
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作者 Denise Schaffner Adhara Lazaro +7 位作者 Peter Deibert Peter Hasselblatt Patrick Stoll Lisa Fauth Manfred W Baumstark Irmgard Merfort Annette Schmitt-Graeff Wolfgang Kreisel 《World Journal of Gastroenterology》 SCIE CAS 2018年第38期4356-4368,共13页
AIM To investigate the potential effect of inhibitors of phosphodiesterase-5(PDE-5) for therapy of portal hypertension in liver cirrhosis.METHODS In the rat model of thioacetamide-induced liver fibrosis/cirrhosis the ... AIM To investigate the potential effect of inhibitors of phosphodiesterase-5(PDE-5) for therapy of portal hypertension in liver cirrhosis.METHODS In the rat model of thioacetamide-induced liver fibrosis/cirrhosis the nitric oxide-cyclic guanosine monophosphate(NO-cGMP) pathway was investigated. Expression and localization of PDE-5, the enzyme that converts vasodilating cGMP into inactive 5'-GMP, was in the focus of the study. Hepatic gene expression of key components of the NO-cGMP pathway was determined by qRT-PCR: Endothelial NO synthase(eNOS), inducible NO synthase(iNOS), soluble guanylate cyclase subunits α1 and β1(sGCa1, sGCb1), and PDE-5. Hepatic PDE-5 protein expression and localization were detected by immunohistochemistry. Serum cGMP concentrations were measured using ELISA. Acute effects of the PDE-5 inhibitor Sildenafil(0.1 mg/kg or 1.0 mg/kg) on portal and systemic hemodynamics were investigated using pressure transducers.RESULTS Hepatic gene expression of eNOS(2.2-fold; P = 0.003), sGCa1(1.7-fold; P = 0.003), sGCb1(3.0-fold; P = 0.003), and PDE-5(11-fold; P = 0.003) was increased in cirrhotic livers compared to healthy livers. Overexpression of PDE-5(7.7-fold; P = 0.006) was less pronounced in fibrotic livers. iNOS expression was only detected in fibrotic and cirrhotic livers. In healthy liver, PDE-5 protein was localized primarily in zone 3 hepatocytes and to a lesser extent in perisinusoidal cells. This zonation was disturbed in cirrhosis: PDE-5 protein expression in perisinusoidal cells was induced approximately 8-fold. In addition, PDE-5-expressing cells were also found in fibrous septa. Serum cGMP concentrations were reduced in rats with cirrhotic livers by approximately 40%. Inhibition of PDE-5 by Sildenafil caused a significant increase in serum cGMP concentrations [+ 64% in healthy rats(P = 0.024), + 85% in cirrhotic rats(P = 0.018)]. Concomitantly, the portal venous pressure was reduced by 19% in rats with liver cirrhosis. CONCLUSION Overexpression and abrogated zonation of PDE-5 likely contribute to the pathogenesis of cirrhotic portal hypertension. PDE-5 inhibition may therefore be a reasonable therapeutic approach for portal hypertension. 展开更多
关键词 Portal hypertension THIOACETAMIDE Nitric oxide Liver cirrhosis Cyclic GUANOSINE MONOPHOSPHATE Phosphodiesterase-5 SILDENAFIL Hepatic stellate cells Metabolic zonation
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纳米晶PbTiO_3负载CuO催化NO分解 被引量:1
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作者 邢丽 薛念华 +3 位作者 陈向科 郭学锋 丁维平 陈懿 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第5期729-732,共4页
A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO d... A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO decomposition reactions. The catalytic properties were tested with a fix-bed micro-reactor. The results showed that the PbTiO3 was inactive for the reactions, but 1wt % Cu/PbTiO3 catalyst gave fairly good activities for NO decomposition at temperature as low as 473 K. Copper species were found well-dispersed but weakly interacted with the support before NO decomposition, and the NO decomposition caused significant change in the environment of the copper species, which became Cu(Ⅰ)and most probably incorporated into surface crystal lattice of the nano-sized PbTiO3. In NO reaction, a large amount of oxygen atoms from the decomposition of NO penetrated into the nano-sized PbTiO3 support and caused small expansion of crystal lattice. The transport of oxygen between the copper species and the catalyst support may be helpful to speed up the kinetic regeneration of active metal sites from oxygen occupancy and resulted in good catalytic performance. 展开更多
关键词 PBTIO3 catalyst surface crystal CUO transport performa lattice active the with and after Cu() small speed metal The area MOST was XPS XRD MAY in be
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Investigation of Microstructure and Phase Composition of Chromic Oxide, AZS/Cr and High-alumina Refractories after Exposure of Basalt and Aluminaboronsilicate Glasses Melts
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作者 Valeriy V.MARTYNENKO Iryna G.SHULYK +1 位作者 Yuliya Ye.MISHNYOVA Tetyana G.TYSHYNA 《China's Refractories》 CAS 2024年第1期1-6,共6页
The microstructure and phase composition of high-alumina,chromic oxide,and AZS/Cr refractories containing 30%and 60%(by mass)Cr_(2)O_(3) after exposure to aluminaboronsilicate glasses and basalt melts depending on the... The microstructure and phase composition of high-alumina,chromic oxide,and AZS/Cr refractories containing 30%and 60%(by mass)Cr_(2)O_(3) after exposure to aluminaboronsilicate glasses and basalt melts depending on the type of melts and temperature have been studied.The mechanisms of refractory corrosion by the used melts and the factors contributing to the inhibition of corrosion development have been investigated by the method of petrographic analysis.On the basis of obtained results,the use of high-alumina,chromic oxide,and AZS/Cr refractories in the sections of glass furnace linings,experiencing the intensive impact of aluminaboronsilicate glasses and basalt melts,has been confirmed and scientifically substantiated. 展开更多
关键词 high-alumina refractories chromic oxide refractories AZS/Cr refractories microstructure phase composition aluminaboronsilicate glasses melts basalt melt
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Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR 被引量:13
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作者 Kenneth Maiese 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第3期372-385,共14页
Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af... Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin(m TOR) is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1(m TORC1) and m TOR Complex 2(m TORC2) and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase(PI 3-K),protein kinase B(Akt),AMP activated protein kinase(AMPK),silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1),Wnt1 inducible signaling pathway protein 1(WISP1),and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM. 展开更多
关键词 Akt AMP activated protein kinase(AMPK) apoptosis Alzheimers disease autophagy β-cell cancer cardiovascular disease caspase CCN family diabetes mellitus epidermal growth factor erythropoietin fibroblast growth factor forkhead transcription factors Fox O FRAP1 hamartin(tuberous sclerosis 1)/tuberin(tuberous sclerosis 2)(TSC1/TSC2) insulin mechanistic target of rapamycin(mTOR) m TOR Complex 1(m T ORC1) m TOR Complex 2(m TORC2) nicotinamide nicotinamide adenine dinucleotide(NAD%PLUS%) non-communicable diseases oxidative stress phosphoinositide 3-kinase(PI 3-K) programmed cell death silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1) sirtuin stem cells wingless Wnt Wnt1 inducible signaling pathway protein 1(WISP1)
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Advancements,strategies,and prospects of solid oxide electrolysis cells(SOECs):Towards enhanced performance and large-scale sustainable hydrogen production 被引量:1
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作者 Amina Lahrichi Youness El Issmaeli +1 位作者 Shankara S.Kalanur Bruno G.Pollet 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期688-715,共28页
Solid oxide electrolysis cells(SOECs)represent a crucial stride toward sustainable hydrogen generation,and this review explores their current scientific challenges,significant advancements,and potential for large-scal... Solid oxide electrolysis cells(SOECs)represent a crucial stride toward sustainable hydrogen generation,and this review explores their current scientific challenges,significant advancements,and potential for large-scale hydrogen production.In SOEC technology,the application of innovative fabrication tech-niques,doping strategies,and advanced materials has enhanced the performance and durability of these systems,although degradation challenges persist,implicating the prime focus for future advancements.Here we provide in-depth analysis of the recent developments in SOEC technology,including Oxygen-SOECs,Proton-SOECs,and Hybrid-SOECs.Specifically,Hybrid-SOECs,with their mixed ionic conducting electrolytes,demonstrate superior efficiency and the concurrent production of hydrogen and oxygen.Coupled with the capacity to harness waste heat,these advancements in SOEC technology present signif-icant promise for pilot-scale applications in industries.The review also highlights remarkable achieve-ments and potential reductions in capital expenditure for future SOEC systems,while elaborating on the micro and macro aspects of sOECs with an emphasis on ongoing research for optimization and scal-ability.It concludes with the potential of SOEC technology to meet various industrial energy needs and its significant contribution considering the key research priorities to tackle the global energy demands,ful-fillment,and decarbonization efforts. 展开更多
关键词 Solid oxide electrolysis cells Proton-SOECs Oxygen-SoECs Hybrid-SOECs Intermediate-high temperature electrolysers Hydrogenproduction
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Neuroprotective potential for mitigating ischemia-reperfusion-induced damage
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作者 Zi Ye Runqing Liu +6 位作者 Hangxing Wang Aizhen Zuo Cen Jin Nan Wang Huiqi Sun Luqian Feng Hua Yang 《Neural Regeneration Research》 SCIE CAS 2025年第8期2199-2217,共19页
Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion injury.Curre... Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion injury.Current studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion injury.However,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional exploration.In this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and autophagy.The therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box O.This review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins expression.This review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk factors.While Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug therapies.Overall,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury. 展开更多
关键词 apoptosis autophagy blood-brain barrier dietary supplements drug HORMONES inflammation NEUROPROTECTION oxidative stress prognosis PYROPTOSIS reperfusion injury risk factors RNA THERAPEUTICS
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