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Reduction of the oxidative damage to H_(2)O_(2)-induced HepG2 cells via the Nrf2 signalling pathway by plant flavonoids Quercetin and Hyperoside
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作者 Meijing Zhang Gaoshuai Zhang +10 位作者 Xiangxing Meng Xinxin Wang Jiao Xie Shaoshu Wang Biao Wang Jilite Wang Suwen Liu Qun Huang Xu Yang Jing Li Hao Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1864-1876,共13页
Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pat... Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pathway predicted by network pharmacology.And the antioxidant effect and mechanism of hyperoside and quercetin were measured and compared in H_(2)O_(2)-induced Hep G2 cells and Caenorhabditis elegans.The findings indicated that quercetin was more effective than hyperoside in reducing oxidative damage,which was proved by improved cell viability,decreased reactive oxygen species(ROS)production,decreased cellular apoptosis,and alleviated mitochondrial damage.In addition,quercetin was more efficient than hyperoside in enhancing the expression of Nrf2-associated m RNAs,increasing the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT),and reducing the cellular malondialdehyde(MDA)content.Quercetin was superior to hyperoside in prolonging the lifespan of worms,decreasing the accumulation of lipofuscin,inhibiting ROS production,and increasing the proportion of skn-1 in the nucleus.With the Nrf2 inhibitor ML385,we verified that quercetin and hyperoside primarily protected the cells against oxidative damage via the Nrf2 signalling pathway.Furthermore,molecular docking and dynamics simulations demonstrated that the quercetin-Kelch-like ECH-associated protein 1(Keap1)complex was more stable than the hyperoside-Keap1 complex.The stable structure of the complex might hinder the binding of Nrf2 and Keap1 to release Nrf2 and facilitate its entry into the nucleus to play an antioxidant role.Overall,quercetin had a better antioxidant than hyperoside. 展开更多
关键词 HYPEROSIDE QUERCETIN HepG2 cell oxidative damage Nrf2 signalling pathway
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Roles of Aqueous Extract of Marigold on Arsenic-Induced Oxidative Damage in Pancreatic Islet β-Cells
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作者 Zongqin Mei Jiao Dai +2 位作者 Guofen Liu Zuoshun He Shiyan Gu 《Journal of Biosciences and Medicines》 2024年第5期19-34,共16页
Roles of Marigold extracts (ME) on arsenic trioxide (ATO)-induced oxidative damage to pancreatic β-cells need to be further elucidated. In this study, NIT-1 cells were treated with different concentrations of and/or ... Roles of Marigold extracts (ME) on arsenic trioxide (ATO)-induced oxidative damage to pancreatic β-cells need to be further elucidated. In this study, NIT-1 cells were treated with different concentrations of and/or ATO, following by the cell viability was detected by CCK8 assay. Then, intracellular reactive oxygen species (ROS) levels, lipid peroxide (MDA) contents and superoxide dismutase (SOD) activity were measured with a fluorescence probe method and colorimetric assay, respectively. The apoptosis rate and morphology was detected and observed with hoechst 33,258 staining assay. The mRNA levels and protein expressions of nuclear factor E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were measured by real-time fluorescence quantitative polymerase chain reaction and protein immunoblotting assay, respectively. Our results indicated that Co-treatment with ME and ATO exacerbated the cell viability decreasing reduced by ATO, while the addition of ME after ATO treatment effectively promote the recovery of ATO reduced survival rates. The ATO group increased apoptosis (P P β-cells by modulating the activation of the Nrf2 signaling pathway. 展开更多
关键词 Arsenic Trioxide Marigold Extracts Nuclear Factor E2-Related Factor 2 oxidative damage
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Cath-KP,a novel peptide derived from frog skin,prevents oxidative stress damage in a Parkinson’s disease model
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作者 Huanpeng Lu Jinwei Chai +9 位作者 Zijian Xu Jiena Wu Songzhe He Hang Liao Peng Huang Xiaowen Huang Xi Chen Haishan Jiang Shaogang Qu Xueqing Xu 《Zoological Research》 SCIE CSCD 2024年第1期108-124,共17页
Parkinson’s disease(PD)is a neurodegenerative condition that results in dyskinesia,with oxidative stress playing a pivotal role in its progression.Antioxidant peptides may thus present therapeutic potential for PD.In... Parkinson’s disease(PD)is a neurodegenerative condition that results in dyskinesia,with oxidative stress playing a pivotal role in its progression.Antioxidant peptides may thus present therapeutic potential for PD.In this study,a novel cathelicidin peptide(Cath-KP;GCSGRFCNLF NNRRPGRLTLIHRPGGDKRTSTGLIYV)was identified from the skin of the Asiatic painted frog(Kaloula pulchra).Structural analysis using circular dichroism and homology modeling revealed a uniqueαββconformation for Cath-KP.In vitro experiments,including free radical scavenging and ferric-reducing antioxidant analyses,confirmed its antioxidant properties.Using the 1-methyl-4-phenylpyridinium ion(MPP^(+))-induced dopamine cell line and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced PD mice,Cath-KP was found to penetrate cells and reach deep brain tissues,resulting in improved MPP^(+)-induced cell viability and reduced oxidative stress-induced damage by promoting antioxidant enzyme expression and alleviating mitochondrial and intracellular reactive oxygen species accumulation through Sirtuin-1(Sirt1)/Nuclear factor erythroid 2-related factor 2(Nrf2)pathway activation.Both focal adhesion kinase(FAK)and p38 were also identified as regulatory elements.In the MPTP-induced PD mice,Cath-KP administration increased the number of tyrosine hydroxylase(TH)-positive neurons,restored TH content,and ameliorated dyskinesia.To the best of our knowledge,this study is the first to report on a cathelicidin peptide demonstrating potent antioxidant and neuroprotective properties in a PD model by targeting oxidative stress.These findings expand the known functions of cathelicidins,and hold promise for the development of therapeutic agents for PD. 展开更多
关键词 Cath-KP PEPTIDE Parkinson’s disease oxidative stress Neuroprotection
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Black radish root extract alleviates sodium valproate-induced liver damage via inhibiting mitochondrial membrane potential collapse and oxidative stress in mice
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作者 Mohammad Hadi Zarei Sami Akbulut +5 位作者 Maryam Zafari Elham Saghaei Zahra Lorigooini Hossein AminiKhoei Somaye Khosravi Elham Bijad 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第7期298-306,共9页
Objective:To explore the effect of black radish(Raphanus sativus L.var niger)root extract on liver enzymes,oxidative stress,and histopathological alterations in mice with sodium valproate-induced hepatotoxicity.Method... Objective:To explore the effect of black radish(Raphanus sativus L.var niger)root extract on liver enzymes,oxidative stress,and histopathological alterations in mice with sodium valproate-induced hepatotoxicity.Methods:Thirty-two mice were divided into four groups:the control group received drinking water by gavage,the second group was administered with 100 mg/kg of sodium valproate,the third group received 300 mg/kg of black radish root extract,and the fourth group was given both sodium valproate(100 mg/kg)and black radish root extract(300 mg/kg).After 28 days,the mice were euthanized,and serum levels of aspartate aminotransferase(AST),alanine aminotransferase(ALT),and alkaline phosphatase(ALP),along with liver malondialdehyde(MDA),reactive oxygen species(ROS),mitochondrial parameters,tumor necrosis factor-alpha(TNF-α)gene expression,and histopathological changes were assessed.Results:Sodium valproate caused hepatic damage in mice,characterized by elevated serum levels of liver enzymes,increased MDA and ROS levels and TNF-αgene expression,as well as histopathological alterations.The black radish root extract significantly alleviated sodium valproate-caused hepatic injury by decreasing the serum levels of ALT and AST,MDA,ROS,TNF-αgene expression,as well as mitochondrial impairment,but did not have a significant effect on sodium valproate-induced histopathological changes.Conclusions:The black radish root extract demonstrates protective effects against sodium valproate-induced liver injury,possibly through mitigating oxidative stress,mitochondrial impairment,and inflammatory mediator expression. 展开更多
关键词 Black radish Raphanus sativus Sodium valproate HEPATOTOXICITY oxidative stress ANTI-INFLAMMATION
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Melatonin alleviates oxidative stress,inflammation,apoptosis,and DNA damage in acrylamide-induced nephrotoxicity in rats
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作者 Fatmaİbaokurgil Hakan Aydin +1 位作者 Serkan Yildirim Emin Sengul 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2023年第3期121-130,共10页
Objective:To investigate the effects of melatonin on renal inflammation,oxidative stress,apoptosis,as well as DNA and tissue damage in acrylamide-induced nephrotoxicity in rats.Methods:Fifty male rats were randomly di... Objective:To investigate the effects of melatonin on renal inflammation,oxidative stress,apoptosis,as well as DNA and tissue damage in acrylamide-induced nephrotoxicity in rats.Methods:Fifty male rats were randomly divided into five groups.The control group received distilled water by gastric lavage for 11days and the acrylamide group was administered acrylamide(50 mg/kg,i.g.)for 11 days.The MEL10+ACR and MEL20+ACR groups received intraperitoneal melatonin 10 and 20 mg/kg,respectively,for 11 days,and acrylamide(50 mg/kg,i.g.)was administered 1h after melatonin injection.The MEL20 group was injected with melatonin(20 mg/kg)for 11 days.Kidney function tests were performed and biochemical and inflammatory parameters were determined.In addition,histopathological,immunohistochemical,and immunofluorescence examinations were carried out.Results:Melatonin significantly abated acrylamide-induced rise in serum urea and creatinine levels.Acrylamide caused oxidative stress,inflammation,apoptosis,as well as DNA and tissue damage in the kidneys.Melatonin treatment alleviated acrylamide-induced renal damage by exhibiting antioxidant,anti-inflammatory,and antiapoptotic effects.Moreover,melatonin significantly ameliorated acrylamide-caused histopathological changes in kidney tissue.Conclusions:Melatonin attenuates acrylamide-induced renal oxidative stress,inflammation,apoptosis,and DNA damage in rats. 展开更多
关键词 Acrylamide APOPTOSIS INFLAMMATION MELATONIN NEPHROTOXICITY oxidative stress Rat
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Protective effects of ferulic acid against ionizing radiation-induced oxidative damage in rat lens through activating Nrf2 signal pathway
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作者 Yueqin Chen Jiawei Shen +4 位作者 Xiaoran Zhang Weiping Gao Qian Cao Feng Yan Chunyan Xue 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第5期687-693,共7页
AIM: To examine the protection of ferulic acid(FA) against ionizing radiation(IR)-induced lens injury in rats, as well as the underlying mechanisms.METHODS: FA(50 mg/kg) was administered to rats for 4 consecutive days... AIM: To examine the protection of ferulic acid(FA) against ionizing radiation(IR)-induced lens injury in rats, as well as the underlying mechanisms.METHODS: FA(50 mg/kg) was administered to rats for 4 consecutive days before they were given 10 Gy γ-radiation, as well as for 3 consecutive days afterward. Two weeks after radiation, the eye tissues were collected. Histological alterations were evaluated by hematoxylineosin staining. Enzyme linked immunosorbent assay(ELISA) was utilized to assess the activities of glutathione reductase(GR) and superoxide dismutase(SOD), as well as the levels of glutathione(GSH) and malondialdehyde(MDA) in the lenses. The protein and m RNA levels of Bcl-2, caspase-3, Bax, heme oxygenase-1(HO-1), and glutamatecysteine ligase catalytic subunit(GCLC) were quantified using Western blot and quantitative reverse transcription polymerase chain reaction, respectively. With nuclear extracts, the nuclear factor erythroid-2 related factor(Nrf2) protein expressions in the nuclei were also measured.RESULTS: Rats exposed to IR showed lens histological alterations which could be alleviated by FA. FA treatment reversed apoptosis-related markers in IR-induced lens, as evidenced by lower levels of Bax and caspase-3 and higher level of Bcl-2. Furthermore, IR induced oxidative damage manifested by decreased GSH level, increased MDA level, and decreased SOD and GR activities. FA boosted nuclear translocation of Nrf2 and increased the expressions of HO-1 and GCLC to inhibit oxidative stress, as evidenced by an increase in GSH, a decrease in MDA, and an increase in GR and SOD activities.CONCLUSION: FA may work well in preventing and treating IR-induced cataract through promoting the Nrf2 signal pathway to attenuate oxidative damage and cell apoptosis. 展开更多
关键词 ferulic acid ionizing radiation LENS oxidative stress NRF2
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Composition and antioxidant activity of Paeonia lactiflora petal flavonoid extract and underlying mechanisms of the protective effect on H_(2)O_(2)-induced oxidative damage in BRL3A cells
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作者 Lei Liu Yingdan Yuan +1 位作者 Jiajia Zuo Jun Tao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第2期335-344,共10页
Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UH... Flavonoids have attracted considerable attention due to their health benefits. This study aimed to investigate the flavonoid profiles and antioxidant activity of Paeonia lactiflora petal flavonoid extract(PPF). The UHPLC-ESI-Q-Exactive HF MS/MS method was established for characterization, and 21 predominant flavonoid compounds were tentatively identified in PPF. Among them, isoscutellarein-7-(6’-acetylallosyl-(1->2)-glucoside) and scutellarin methylester were discovered in PPF for the first time. Pretreatment with PPF significantly reduced H2O2-induced cell damage, ROS accumulation, and malondialdehyde content and increased the activity of SOD, CAT, and GSH-Px in buffalo rat liver 3A(BRL3A) cells. Moreover, the expression of nuclear Factor E2-related factor(Nrf2) was upregulated by PPF, whose expression trend was consistent with that of heme oxygenase-1(HO-1), glutamate-cysteine ligase catalytic subunit(GCLC), and NAD(P)H quinone oxidoreductase-1(NQO1). These findings suggested that herbaceous peony flavonoids can be used as a natural bioactive agent to prevent oxidative stress. 展开更多
关键词 Antioxidant activity Flavonoid Herbaceous peony petal oxidative stress Solid-phase extraction
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Selenoproteins synergistically protect porcine skeletal muscle from oxidative damage via relieving mitochondrial dysfunction and endoplasmic reticulum stress
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作者 Jinzhong Jing Ying He +10 位作者 Yan Liu Jiayong Tang Longqiong Wang Gang Jia Guangmang Liu Xiaoling Chen Gang Tian Jingyi Cai Lianqiang Che Bo Kang Hua Zhao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第5期2180-2196,共17页
Background The skeletal muscle of pigs is vulnerable to oxidative damage,resulting in growth retardation.Selenoproteins are important components of antioxidant systems for animals,which are generally regulated by diet... Background The skeletal muscle of pigs is vulnerable to oxidative damage,resulting in growth retardation.Selenoproteins are important components of antioxidant systems for animals,which are generally regulated by dietary selenium(Se)level.Here,we developed the dietary oxidative stress(DOS)-inducing pig model to investigate the protective effects of selenoproteins on DOS-induced skeletal muscle growth retardation.Results Dietary oxidative stress caused porcine skeletal muscle oxidative damage and growth retardation,which is accompanied by mitochondrial dysfunction,endoplasmic reticulum(ER)stress,and protein and lipid metabolism disorders.Supplementation with Se(0.3,0.6 or 0.9 mg Se/kg)in form of hydroxy selenomethionine(OH-SeMet)linearly increased muscular Se deposition and exhibited protective effects via regulating the expression of selenotranscriptome and key selenoproteins,which was mainly reflected in lower ROS levels and higher antioxidant capacity in skeletal muscle,and the mitigation of mitochondrial dysfunction and ER stress.What’s more,selenoproteins inhibited DOS induced protein and lipid degradation and improved protein and lipid biosynthesis via regulating AKT/mTOR/S6K1 and AMPK/SREBP-1 signalling pathways in skeletal muscle.However,several parameters such as the activity of GSH-Px and T-SOD,the protein abundance of JNK2,CLPP,SELENOS and SELENOF did not show dose-dependent changes.Notably,several key selenoproteins such as MSRB1,SELENOW,SELENOM,SELENON and SELENOS play the unique roles during this protection.Conclusions Increased expression of selenoproteins by dietary OH-SeMet could synergistically alleviate mitochondrial dysfunction and ER stress,recover protein and lipid biosynthesis,thus alleviate skeletal muscle growth retardation.Our study provides preventive measure for OS-dependent skeletal muscle retardation in livestock husbandry. 展开更多
关键词 Dietary oxidative stress Endoplasmic reticulum stress Growth retardation Mitochondrial dysfunction SELENOPROTEINS Skeletal muscle
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Polyphenols and pectin enriched golden kiwifruit (Actinidia chinensis) alleviates high fructose-induced glucolipid disorders and hepatic oxidative damage in rats:in association with improvement of fatty acids metabolism
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作者 Aamina Alim Ting Li +4 位作者 Tanzeela Nisar Zeshan Ali Daoyuan Ren Yueyue Liu Xingbin Yang 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1872-1884,共13页
This study aimed to investigate the protective effects of fleshes from two Actinidia chinensis(ACF), pericarps from two A. chinensis(ACP), and fleshes with pericarps from two A. chinensis(ACFP)on high fructose(HF)-ins... This study aimed to investigate the protective effects of fleshes from two Actinidia chinensis(ACF), pericarps from two A. chinensis(ACP), and fleshes with pericarps from two A. chinensis(ACFP)on high fructose(HF)-instigated dyslipidemia, hepatic steatosis, oxidative stress, insulin resistance, and fatty acid metabolism disorders in rats. In general, the above abnormalities were improved after 10 weeks intervention of ACF, ACP, and ACFP. Especially, ACFP considerably ameliorated HF-induced abnormal changes in body weight gain, serum TC, TG, LDL-C and HDL-C levels, as well as serum and hepatic SFAs, MUFAs and PUFAs contents. ACFP also alleviated HF-induced hyperglycemia and hyperinsulinemia, stabilized HF-caused increase in hepatic MDA and serum ALT, AST levels, and restored HF-declined hepatic T-SOD and GSH-Px activities. Besides, histopathology of the liver further endorsed the protective effects of ACFP on hepatocellular injury. Moreover, ACFP increased HF-dropped acetic, propionic and butyric acid levels. Overall, ACFP employs more efficacious protective effects against HF-induced metabolic disorders and liver damage than ACF and ACP. This study delivers a scientific foundation for developing kiwifruit(counting peel)-based dietary supplements for those with glucolipid-metabolic disorders and liver damage. 展开更多
关键词 Actinidia chinensis peel Lipid homeostasis oxidative stress Insulin resistance Hepatocellular injury Fatty acid metabolism
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Inhibitory effect of water soluble propolis on oxidative damage in rats with ulcerative colitis
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作者 ZHOU Hua ZHANG Min JIANG Wen-tao 《Journal of Hainan Medical University》 CAS 2023年第18期15-22,共8页
Objective:To investigate the effects of water-soluble propolis(WSP)on the levels of colonic mucosal inflammation and oxidative stress in rats with ulcerative colitis(UC).Methods:The UC rat model was made by sodium dex... Objective:To investigate the effects of water-soluble propolis(WSP)on the levels of colonic mucosal inflammation and oxidative stress in rats with ulcerative colitis(UC).Methods:The UC rat model was made by sodium dextran sulfate(DSS).Forty-eight male rats were randomly divided into six groups:the normal group(N group),the control group(C group),the positive control group(P group),the low-dose propolis group(L group),he medium-dose propolis(M group)and the high-dose propolis group(H group).The protective effect of WSP on DSS induced UC rats was evaluated by preadministration and re-construction model.Body mass,disease activity index(DAI),blood stool,colon length,intestinal mucosal damage index(CMDI)of rats were observed.The indexes of medulla peroxidase(MPO),superoxidase(SOD),malondialdehyde(MDA)and glutathione peroxidase(GSH-Px)in colon tissue were determined by ELISA.Results:the oxidative stress level of colon tissue in the model group was increased and neutrophils were activated.After medium and high concentration propolis intervention,the oxidative stress level was reduced and the colonic inflammatory injury was relieved.Conclusion:WSP can improve the activity of SOD,GSH-Px and other endogenous antioxidant enzymes,reduce oxidative stress products,inhibit the activity of neutrophil and other mechanisms to relieve intestinal inflammation in experimental UC rat model. 展开更多
关键词 Water-soluble propolis Ulcerative colitis oxidative stress Intestinal mucosal barrier Natural products
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Enhanced structural damage behavior of liquid-filled tank by reactive material projectile impact 被引量:1
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作者 Jianwen Xie Yuanfeng Zheng +4 位作者 Zhenyang Liu Chengzhe Liu Aoxin Liu Pengwan Chen Haifu Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期211-229,共19页
A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was s... A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was studied in detail.PTFE/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering process.The projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/s.The corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system,and further compared to those of steel and aluminum projectiles.Significantly different from the conical cavity formed by the inert metal projectile,the cavity formed by the RMP appeared as an ellipsoid with a conical front.The RMPs were demonstrated to enhance the radial growth velocity of cavity,the global HRAM pressure amplitude and the front panel damage,indicating the enhanced HRAM and structural damage behavior.Furthermore,combining the impact-induced fragmentation and deflagration characteristics,the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was analyzed.The mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse analysis.Finally,the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and analyzed.It was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior. 展开更多
关键词 Reactive material projectile Hydrodynamic ram Enhanced structural damage Liquid-filled tank Impact
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A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling 被引量:1
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作者 Shahriyar Heidarzadeh Ali Saeidi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1993-2005,共13页
We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensiti... We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensities.To account for these variations,we utilized a Monte Carlo Simulation(MCS)technique coupled with the finite difference code FLAC^(3D),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GSIs)and subjected to different states of static loading.To quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BSR))and one strain-based failure criterion(plastic damage index(PDI)).Based on these criteria,we then developed fragility curves.Additionally,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock mass.The results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the tunnel.Therefore,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress state.Our method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels. 展开更多
关键词 Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3D Numerical modeling
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Damage evolution of rock-encased-backfill structure under stepwise cyclic triaxial loading 被引量:1
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作者 Xin Yu Yuye Tan +4 位作者 Weidong Song John Kemeny Shengwen Qi Bowen Zheng Songfeng Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期597-615,共19页
Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB ... Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground excavations. 展开更多
关键词 Rock and backfill Triaxial cyclic loading Volume fraction damage evolution 3D visualization
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Effects of Imazethapyr-Based Herbicide Formulation in the Zebrafish (Danio rerio) Hepatocyte Cell Line (ZF-L): Cytotoxicity and Oxidative Stress
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作者 Edila Maria Kickhöfel Ferrer Milena Mattes Cerveira +10 位作者 Pedro Henrique Flores Da Cruz Cleiton Jesus Andrade Pereira Lucas Moraes Berneira Claudio Martin Pereira de Pereira Nathalia Stark Pedra Roselia Maria Spanevello Jean Carlos Bauer Vieira Clarissa Piccinin Frizzo Mateus Tavares Kütter Janice Luehring Giongo Rodrigo de Almeida Vaucher 《Journal of Environmental Protection》 2024年第6期747-765,共19页
Seizures of agrochemical formulations have increased in Brazil and Rio Grande do Sul is among the Brazilian states with the highest number of seizures of these products obtained illicitly. The use of illicit formulati... Seizures of agrochemical formulations have increased in Brazil and Rio Grande do Sul is among the Brazilian states with the highest number of seizures of these products obtained illicitly. The use of illicit formulations can cause significant harm to agricultural production, the environment, and non-target species. This study evaluated the cytotoxicity and oxidative stress of a seized formulation containing the herbicide imazethapyr (IMZT). Characterization of the herbicide included gas chromatography-mass spectrometry (GC-MS) and thermal analyses (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)). Hemolytic and cytotoxicity assays in ZF-L hepatic cells showed IC50 values of 12.75 µg/mL, 3.01 µg/mL, 2.67 µg/mL, and 1.61 µg/mL for erythrocytes, [3(4,5-dimethyl)-2 bromide-5 diphenyl tetrazolium] (MTT), neutral red (NR), and lactate dehydrogenase (LDH) assays, respectively. The median IC50 of 2.84 µg/mL was used in oxidative stress assays, revealing increased reactive oxygen species (ROS) production, reduced total sulfhydryl content, and decreased superoxide dismutase (SOD) and catalase (CAT) activity. This study is the first to report in vitro oxidative stress induced by IMZT in the ZF-L cell line, emphasizing the importance of in vitro assays for assessing the toxic effects of seized agrochemicals on human health and the environment. 展开更多
关键词 Agrochemical IMIDAZOLINONE ZEBRAFISH Cell Viability oxidative damage
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Cosmetic or Dietary Vegetable Oils Sampled in the Cameroonian Market May Not Expose Consumers to Lipid Oxidation Products Generating Oxidative Stress and Inflammation
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作者 Ferdinand Kouoh Elombo Erika Van Damme +5 位作者 Clara Delepine David Depraetere Ludovic Chaveriat Paul Lunga Keilah Nico Fréderic Njayou Patrick Martin 《American Journal of Plant Sciences》 CAS 2024年第3期193-202,共10页
Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ ... Vegetable oils are a source of energy, essential fatty acids, antioxidants and fat-soluble vitamins useful for human health care and development. These oils also contribute to organoleptic quality of their products’ derivatives. However, their chemical and physical properties can be modified by the mode of their extraction, storage and distribution. These modifications might negatively affect the nutritional quality of the oils. The goals of this study were to: sample different vegetable oils for cosmetic or dietary use marketed in Cameroon, and verify purity and oxidation states of each kind of oil through determination of its acidity, iodine, peroxide, saponification, refractive indexes and the conformity of the labeling. The carotene content, the level of polar components and specific absorbance were also determined. As the result, six oils namely palm, palm kernel, coconut, black cumin, peanut and shea butter were collected. Apart from labeling, chemicals and physicals parameters analyzed were generally in accordance with the Cameroonian and Codex Alimentarius standard. This study suggests that vegetable oils sampled in the Cameroonian market may not expose consumers to lipid oxidation products generating pathological oxidative stress and inflammation. However, efforts in application of existing standard need to be done as far as labeling are concerned. 展开更多
关键词 Vegetable Oils Quality Control Labeling Compliance Lipid oxidation oxidative Pathology
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Biochanin A attenuates spinal cord injury in rats during early stages by inhibiting oxidative stress and inflammasome activation 被引量:1
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作者 Xigong Li Jing Fu +3 位作者 Ming Guan Haifei Shi Wenming Pan Xianfeng Lou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2050-2056,共7页
Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord ... Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord injury is still unclea r. In this study,a rat model of spinal cord injury was established using the heavy o bject impact method,and the rats were then treated with Biochanin A(40 mg/kg) via intrape ritoneal injection for 14 consecutive days.The res ults showed that Biochanin A effectively alleviated spinal cord neuronal injury and spinal co rd tissue injury,reduced inflammation and oxidative stress in spinal cord neuro ns,and reduced apoptosis and pyroptosis.In addition,Biochanin A inhibited the expression of inflammasome-related proteins(ASC,NLRP3,and GSDMD)and the Toll-like receptor 4/nuclear factor-κB pathway,activated the Nrf2/heme oxygenase 1 signaling pathway,and increased the expression of the autophagy markers LC3 Ⅱ,Beclin-1,and P62.Moreove r,the therapeutic effects of Biochanin A on early post-s pinal cord injury were similar to those of methylprednisolone.These findings suggest that Biochanin A protected neurons in the injured spinal cord through the Toll-like receptor 4/nuclear factor κB and Nrf2/heme oxygenase 1 signaling pathways.These findings suggest that Biochanin A can alleviate post-spinal cord injury at an early stage. 展开更多
关键词 apoptosis AUTOPHAGY Biochanin A heme oxygenase 1 INFLAMMATION Nrf2 protein nuclear factor kappa-B oxidative stress spinal cord injury Toll-like receptor 4
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Stress-corrosion coupled damage localization induced by secondary phases in bio-degradable Mg alloys:phase-field modeling
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作者 Chao Xie Shijie Bai +2 位作者 Xiao Liu Minghua Zhang Jianke Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期361-383,共23页
In this study,a phase-field scheme that rigorously obeys conservation laws and irreversible thermodynamics is developed for modeling stress-corrosion coupled damage(SCCD).The coupling constitutive relationships of the... In this study,a phase-field scheme that rigorously obeys conservation laws and irreversible thermodynamics is developed for modeling stress-corrosion coupled damage(SCCD).The coupling constitutive relationships of the deformation,phase-field damage,mass transfer,and electrostatic field are derived from the entropy inequality.The SCCD localization induced by secondary phases in Mg is numerically simulated using the implicit iterative algorithm of the self-defined finite elements.The quantitative evaluation of the SCCD of a C-ring is in good agreement with the experimental results.To capture the damage localization,a micro-galvanic corrosion domain is defined,and the buffering effect on charge migration is explored.Three cases are investigated to reveal the effect of localization on corrosion acceleration and provide guidance for the design for resistance to SCCD at the crystal scale. 展开更多
关键词 Phase field Mg alloys Stress-corrosion coupled damage damage localization Finite element method
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YOLO-Based Damage Detection with StyleGAN3 Data Augmentation for Parcel Information-Recognition System
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作者 Seolhee Kim Sang-Duck Lee 《Computers, Materials & Continua》 SCIE EI 2024年第7期195-215,共21页
Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequentl... Damage to parcels reduces customer satisfactionwith delivery services and increases return-logistics costs.This can be prevented by detecting and addressing the damage before the parcels reach the customer.Consequently,various studies have been conducted on deep learning techniques related to the detection of parcel damage.This study proposes a deep learning-based damage detectionmethod for various types of parcels.Themethod is intended to be part of a parcel information-recognition systemthat identifies the volume and shipping information of parcels,and determines whether they are damaged;this method is intended for use in the actual parcel-transportation process.For this purpose,1)the study acquired image data in an environment simulating the actual parcel-transportation process,and 2)the training dataset was expanded based on StyleGAN3 with adaptive discriminator augmentation.Additionally,3)a preliminary distinction was made between the appearance of parcels and their damage status to enhance the performance of the parcel damage detection model and analyze the causes of parcel damage.Finally,using the dataset constructed based on the proposed method,a damage type detection model was trained,and its mean average precision was confirmed.This model can improve customer satisfaction and reduce return costs for parcel delivery companies. 展开更多
关键词 Parcel delivery service damage detection damage classification data augmentation generative adversarial network
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Does HSP27 injection induce glaucoma damage in mice?
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作者 Stephanie C.Joachim Sabrina Reinehr 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2347-2348,共2页
In a further aging society,excellent eyesight is an integral part of overall well-being and quality of life.Preserving good vision is crucial to maintaining mobility,independence,and mental health.There can be several... In a further aging society,excellent eyesight is an integral part of overall well-being and quality of life.Preserving good vision is crucial to maintaining mobility,independence,and mental health.There can be several reasons for visual impairment in elderly people,these include age-related macular degeneration,the leading cause of vision loss among older adults,cataract,glaucoma,diabetic retinopathy,retinal detachment,and others. 展开更多
关键词 HSP27 INJECTION damage
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Modulation of p75 neurotrophin receptor mitigates brain damage following ischemic stroke in mice
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作者 Golnoush Mirzahosseini Tauheed Ishrat 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2093-2094,共2页
Stroke is a significant leading cause of death and disability in the United States(Tsao et al.,2022).Approximately 87% of strokes fall into the ischemic category,mainly caused by arterial blockage(Jayaraj et al.,2019)... Stroke is a significant leading cause of death and disability in the United States(Tsao et al.,2022).Approximately 87% of strokes fall into the ischemic category,mainly caused by arterial blockage(Jayaraj et al.,2019).Although the only FDA-approved effective medication is tissue plasminogen activator(tPA),it should be administrated within 4.5 hours of ischemic stroke.Furthermore,tPA has been an integral part of managing acute ischemic stro ke. 展开更多
关键词 damage ARTERIAL DEATH P75
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