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Evaluation of Technical Education by Using a Modern Structured MOODLE Laboratory Course, in Relation to Recent Data
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作者 Gerasimos Vlassopoulos George Albert Karikas +4 位作者 Efstathia Papageorgiou Ioannis Psaromiligkos Niki Giannouli Pigi Vlassopoulou Petros Karkalousos 《Journal of Intelligent Learning Systems and Applications》 2024年第3期316-339,共24页
E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo... E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant. 展开更多
关键词 Information and Communication Technologies (ICT) Distance Learning E-Learning students Opinions Education in Greece I.C.T. in Greece sTUDENTs Pupils Adults Adult students MOODLE MOOC (V.H.s.) Vocational High schools (s.H.V.T.) schools of Higher Vocational Training VOCATIONAL Profession Interactive Lessons Courses Training Laboratory Course secondary Education Automotive systems Car systems
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Overexpression of heme oxygenase-1 protects smooth muscle cells against oxidative injury and inhibits cell proliferation 被引量:17
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作者 MIN ZHANG, BAO HuI ZHANG, LI CHEN, WEI AN1 Institute of Sports Medicine, The Third Hospital, Peking University, Beijing 100083, China 2Department of Cell Biology, Capital University of Medical Sciences, Beijing 100054, China 《Cell Research》 SCIE CAS CSCD 2002年第2期123-132,共10页
To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we establishe... To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of HO-1, and this effect might be related to decreased phosphorylation of MAPK. These results suggest that the overexpression of introduced hHO-1 is potentially able to reduce the risk factors of atherosclerosis, partially due to its cellular protection against oxidative injury and to its inhibitory effect on cellular proliferation. 展开更多
关键词 Animals Blotting Northern Blotting southern Blotting Western Cell Division Cell survival Cells Cultured Cyclic GMP Dose-Response Relationship Drug Flow Cytometry Free Radicals Genetic Vectors Heme Oxygenase (Decyclizing) Heme Oxygenase-1 Humans Hydrogen Peroxide MAP Kinase signaling system Male Membrane Proteins Muscle smooth Myocytes smooth Muscle OXIDANTs Oxidative stress Oxygen Phosphorylation RATs Rats sprague-Dawley Research support Non-U.s. Gov't RETROVIRIDAE Time Factors Transfection
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Multi-compartmental migration and ecological-health risks of trace metals in Dexing mining concentration areas:A holistic quantitative assessment
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作者 Xiao-tao Zhang Jun-jie Hu +3 位作者 Bin Shen Man-dan Huang Shan-hong Lan Zhi-hang Xin 《China Geology》 2025年第3期500-513,I0005-I0025,共35页
To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and ... To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and Ni in China’s Dexing copper mining district through paired sampling of water-amphibians,soil-earthworms,and air-lichens.Advanced methodologies were employed,including ICP-MS quantification for heavy metals,geochemical indices(Igeo,BCF,BAF)to assess bioavailability,NMDS for source apportionment,and HPLC to detect DNA methylation alterations.Aquatic systems exhibited severe Cd/Pb enrichment(16.25-24.42μg/L;11-15×WHO limits),while agricultural soils showed extreme Cd contamination(1.5 mg/kg;15×background).Biota displayed metal-specific accumulation:frogs achieved BCFs>1,000 for Pb/Cd,earthworms showed pH-modulated BAFs>2.5 for Cd/As,and lichens recorded 100-1,000×atmospheric Cr enrichment.NMDS resolved three contamination pathways:mining-derived Cd/Pb/As(MDS1=2.56),atmospheric Cr(PC2=1.84),and geogenic Ni.Cd dominated ecological risks(Eri=554.25;RI 300),while atmospheric Cr drove carcinogenic risks(TCR=4.11×10^(-5))exceeding safety thresholds.The source-media-biota-risk framework pioneers the integration of geochemical transport with epigenetic toxicity biomarkers,demonstrating that sub-lethal Cd/Pb exposure induces genome-wide DNA hypomethylation(2.4%-6.6%reduction;ρ=−0.71 to−0.91).This paradigm shift prioritizes bioavailability-informed regulations over concentration-based metrics,offering actionable strategies for sustainable development goals-aligned mining pollution control. 展开更多
关键词 Copper mining operations Trace metal(loid)s contamination Cross-media transfer Water-amphibians soil-earthworms Air-lichens DNA methylation biomarkers Biogeochemical processes Risk assessment sustainable Development Goals(sDG3) Dexing mining area Environmental geological survey engineering
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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease 被引量:1
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作者 Hongli Li Jianhua Huang +4 位作者 Di Zhao Lemei Zhu Zheyu Zhang Min Yi Weijun Peng 《Neural Regeneration Research》 SCIE CAS 2025年第10期2982-2997,共16页
Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzhei... Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease development.To do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of age.Twelve-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 mice.Notably,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 mice.These findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies. 展开更多
关键词 Alzheimer’s disease APP/Ps1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis
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Cardiometabolic diseases in patients with inflammatory bowel disease:An evidence-based review
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作者 Krishneel Dutt Abhinav Vasudevan +2 位作者 Alexander Hodge Tuan L Nguyen Ashish R Srinivasan 《World Journal of Gastroenterology》 2025年第24期1-24,共24页
Metabolic syndrome-comprising central adiposity,dyslipidaemia,insulin resis-tance,and hypertension-is a major risk factor for cardiometabolic diseases such as ischaemic heart disease,stroke,and type 2 diabetes.Its glo... Metabolic syndrome-comprising central adiposity,dyslipidaemia,insulin resis-tance,and hypertension-is a major risk factor for cardiometabolic diseases such as ischaemic heart disease,stroke,and type 2 diabetes.Its global prevalence is rising,largely driven by urbanization,sedentary lifestyles,and dietary changes.These same factors are also associated with the increasing incidence of inflammatory bowel diseases(IBD),including Crohn’s disease and ulcerative colitis.Emerging evidence supports a potential biological link between chronic gastrointestinal inflammation and the later development of cardiometabolic disorders;a con-nection that is particularly relevant for patients with IBD.Comparative studies examining cardiometabolic risk associated with Crohn’s disease versus ulcerative colitis have reported inconsistent findings,likely due to confounding factors such as age,lifestyle,and comorbidities.This review summarizes current evidence linking IBD and cardiometabolic disorders,and highlights the need for clinicians to recognize cardiometabolic risk in patients with IBD.Future research should investigate whether treat-to-target strategies focused on controlling intestinal inflammation can simultaneously improve both long-term IBD and cardiometabolic outcomes. 展开更多
关键词 Inflammatory bowel disease Crohn’s disease Ulcerative colitis Metabolic syndrome OBEsITY Cardiovascular disease sTROKE Metabolic liver disease Cardiometabolic diseases Gastrointestinal inflammation
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Calcium bridges built by mitochondria-associated endoplasmic reticulum membranes:potential targets for neural repair in neurological diseases 被引量:1
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作者 Yichen Peng Li Zhou +10 位作者 Yaju Jin Danli Wu Na Chen Chengcai Zhang Hongpeng Liu Chunlan Li Rong Ning Xichen Yang Qiuyue Mao Jiaxin Liu Pengyue Zhang 《Neural Regeneration Research》 2025年第12期3349-3369,共21页
The exchange of information and materials between organelles plays a crucial role in regulating cellular physiological functions and metabolic levels.Mitochondria-associated endoplasmic reticulum membranes serve as ph... The exchange of information and materials between organelles plays a crucial role in regulating cellular physiological functions and metabolic levels.Mitochondria-associated endoplasmic reticulum membranes serve as physical contact channels between the endoplasmic reticulum membrane and the mitochondrial outer membrane,formed by various proteins and protein complexes.This microstructural domain mediates several specialized functions,including calcium(Ca^(2+))signaling,autophagy,mitochondrial morphology,oxidative stress response,and apoptosis.Notably,the dysregulation of Ca^(2+)signaling mediated by mitochondria-associated endoplasmic reticulum membranes is a critical factor in the pathogenesis of neurological diseases.Certain proteins or protein complexes within these membranes directly or indirectly regulate the distance between the endoplasmic reticulum and mitochondria,as well as the transduction of Ca^(2+)signaling.Conversely,Ca^(2+)signaling mediated by mitochondria-associated endoplasmic reticulum membranes influences other mitochondria-associated endoplasmic reticulum membraneassociated functions.These functions can vary significantly across different neurological diseases—such as ischemic stroke,traumatic brain injury,Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,and Huntington's disease—and their respective stages of progression.Targeted modulation of these disease-related pathways and functional proteins can enhance neurological function and promote the regeneration and repair of damaged neurons.Therefore,mitochondria-associated endoplasmic reticulum membranes-mediated Ca^(2+)signaling plays a pivotal role in the pathological progression of neurological diseases and represents a significant potential therapeutic target.This review focuses on the effects of protein complexes in mitochondria-associated endoplasmic reticulum membranes and the distinct roles of mitochondria-associated endoplasmic reticulum membranes-mediated Ca^(2+)signaling in neurological diseases,specifically highlighting the early protective effects and neuronal damage that can result from prolonged mitochondrial Ca^(2+)overload or deficiency.This article provides a comprehensive analysis of the various mechanisms of Ca^(2+)signaling mediated by mitochondria-associated endoplasmic reticulum membranes in neurological diseases,contributing to the exploration of potential therapeutic targets for promoting neuroprotection and nerve repair. 展开更多
关键词 Alzheimer’s disease amyotrophic lateral sclerosis Ca^(2%PLUs%)signaling conduction Huntington’s disease ischemic stroke MAMMALs mitochondrial dynamics neural function repair oxidative stress Parkinson’s disease traumatic brain injury
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5D Projection Theory Fermat’s Last Theorem Perelman’s Mappings self-Rotation Dipolar MAGNETIC FIELD of stars LAWs of sTELLAR Magnetism LAWs of sTELLAR Angular Momentum MAGNETIC Bode’s Law NON-EXIsTENCE of Gravitational singularity semion state of Atoms in sTELLAR surface MAGNETIC storm Planetary MAGNETIC FIELD Maxwell Equations at 4D-5D Boundary MAGNETIC Fields of the Trappist-1 system
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Riemann Hypothesis, Catholic Information and Potential of Events with New Techniques for Financial and Other Applications
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作者 Prodromos Char. Papadopoulos 《Advances in Pure Mathematics》 2021年第5期524-572,共49页
In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic... In this research we are going to define two new concepts: a) “The Potential of Events” (EP) and b) “The Catholic Information” (CI). The term CI derives from the ancient Greek language and declares all the Catholic (general) Logical Propositions (<img src="Edit_5f13a4a5-abc6-4bc5-9e4c-4ff981627b2a.png" width="33" height="21" alt="" />) which will true for every element of a set A. We will study the Riemann Hypothesis in two stages: a) By using the EP we will prove that the distribution of events e (even) and o (odd) of Square Free Numbers (SFN) on the axis Ax(N) of naturals is Heads-Tails (H-T) type. b) By using the CI we will explain the way that the distribution of prime numbers can be correlated with the non-trivial zeros of the function ζ(s) of Riemann. The Introduction and the Chapter 2 are necessary for understanding the solution. In the Chapter 3 we will present a simple method of forecasting in many very useful applications (e.g. financial, technological, medical, social, etc) developing a generalization of this new, proven here, theory which we finally apply to the solution of RH. The following Introduction as well the Results with the Discussion at the end shed light about the possibility of the proof of all the above. The article consists of 9 chapters that are numbered by 1, 2, …, 9. 展开更多
关键词 Twin Problem Twin’s Problem Unsolved Mathematical Problems Prime Number Problems Millennium Problems Riemann Hypothesis Riemann’s Hypothesis Number Theory Information Theory Probabilities statistics Management Financial Applications Arithmetical Analysis Optimization Theory stock Exchange Mathematics Approximation Methods Manifolds Economical Mathematics Random Variables space of Events strategy Games Probability Density stock Market Technical Analysis Forecasting
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Achieving Large Six Non-Volatile States via Monolayer Homologous Multiferroic MoPtGe_(2)S_(6)in van der Waals Tunnel Junctions 被引量:1
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作者 Ruixia Yang Xujin Zhang +3 位作者 Jianhua Xiao Zhi Yan Fang Wang Xiaohong Xu 《Chinese Physics Letters》 2025年第7期251-262,共12页
Multiferroic tunnel junctions(MFTJs),which combine tunneling magnetoresistance(TMR)and electroresistance(TER)efects,have emerged as key candidates for data storage.Two-dimensional van der Waals(vdW)MFTJs,in particular... Multiferroic tunnel junctions(MFTJs),which combine tunneling magnetoresistance(TMR)and electroresistance(TER)efects,have emerged as key candidates for data storage.Two-dimensional van der Waals(vdW)MFTJs,in particular,are promising spintronic devices for the post-Moore era.However,these vdW MFTJs are typically based on multiferroics composed of ferromagnetic and ferroelectric materials or multilayer magnetic materials with sliding ferroelectricity,which increases device fabrication complexity.In this work,we design a vdW MFTJ using bilayer MoPtGe_(2)S_(6),a material with homologous multiferroicity in each monolayer,combined with symmetric PtTe_(2)electrodes.Using frst-principles calculations based on density functional theory and nonequilibrium Green's functions,we theoretically explore the spin-polarized electronic transport properties of this MFTJ.By controlling the ferroelectric and ferromagnetic polarization directions of bilayer MoPtGe_(2)S_(6),the MFTJ can exhibit six distinct non-volatile resistance states,with maximum TMR(137%)and TER(1943%)ratios.Under biaxial strain,TMR and TER can increase to 265%and 4210%,respectively.The TER ratio also increases to 2186%under a 0.1 V bias voltage.Remarkably,the MFTJ exhibits a pronounced spin-fltering and a signifcant negative diferential resistance efect.These fndings not only highlight the potential of monolayer multiferroic MoPtGe_(2)S_(6)for MFTJs but also ofer valuable theoretical insights for future experimental investigations. 展开更多
关键词 multiferroic tunnel junctions mftjs which multiferroic tunnel junctions data storagetwo dimensional tunneling magnetoresistance tmr multilayer magnetic materials sliding ferroelectricitywhich spintronic devices monolayer moptge s
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’... Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease. 展开更多
关键词 ALPHA-sYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice
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作者 Yanli Zhang Tian Li +8 位作者 Jie Miao Zhina Zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei Zhang Haiting Li Qiang Su Junhong Guo 《Neural Regeneration Research》 SCIE CAS 2025年第2期533-547,共15页
In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of A... In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of Alzheimer’s disease remains unclear.This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying mechanism.We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse model.Additionally,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits.Interestingly,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 mice.This effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa B.Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice.These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease amyloid-β APP/Ps1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1
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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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Potential common pathogenesis of several neurodegenerative diseases
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作者 Ting Fan Jiaman Peng +3 位作者 Huiting Liang Wenzhi Chen Junlin Wang Renshi Xu 《Neural Regeneration Research》 2026年第3期972-988,共17页
With the gradual advancement of research methods and technologies,various biological processes have been identified as playing roles in the pathogenesis of neurodegenerative diseases.However,current descriptions of th... With the gradual advancement of research methods and technologies,various biological processes have been identified as playing roles in the pathogenesis of neurodegenerative diseases.However,current descriptions of these biological processes do not fully explain the onset,progression,and development of these conditions.Therefore,exploration of the pathogenesis of neurodegenerative diseases remains a valuable area of research.This review summarizes the potential common pathogeneses of Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,Huntington’s disease,frontotemporal lobar dementia,and Lewy body disease.Research findings have indicated that several common biological processes,including aging,genetic factors,progressive neuronal dysfunction,neuronal death and apoptosis,protein misfolding and aggregation,neuroinflammation,mitochondrial dysfunction,axonal transport defects,and gut microbiota dysbiosis,are involved in the pathogenesis of these six neurodegenerative diseases.Based on current information derived from diverse areas of research,these biological processes may form complex pathogenic networks that lead to distinctive types of neuronal death in neurodegenerative diseases.Furthermore,promoting the regeneration of damaged neurons may be achievable through the repair of affected neural cells if the underlying pathogenesis can be prevented or reversed.Hence,these potential common biological processes may represent only very small,limited elements within numerous intricate pathogenic networks associated with neurodegenerative diseases.In clinical treatment,interfering with any single biological process has proven insufficient to completely halt the progression of neurodegenerative diseases.Therefore,future research on the pathogenesis of neurodegenerative diseases should focus on uncovering the complex pathogenic networks,rather than isolating individual biological processes.Based on this,therapies that aim to block or reverse various targets involved in the potential pathogenic mechanisms of neurodegenerative diseases may be promising directions,as current treatment methods that focus on halting a single pathogenic factor have not achieved satisfactory efficacy. 展开更多
关键词 aging Alzheimer’s disease amyotrophic lateral sclerosis frontotemporal lobar dementia genetics Huntington’s disease Lewy body disease Parkinson’s disease progressive neuron dysfunction and death protein misfolding
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Exosomes in neurodegenerative diseases:Therapeutic potential and modification methods
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作者 Hongli Chen Na Li +7 位作者 Yuanhao Cai Chunyan Ma Yutong Ye Xinyu Shi Jun Guo Zhibo Han Yi Liu Xunbin Wei 《Neural Regeneration Research》 2026年第2期478-490,共13页
In recent years,exosomes have garnered extensive attention as therapeutic agents and early diagnostic markers in neurodegenerative disease research.Exosomes are small and can effectively cross the blood-brain barrier,... In recent years,exosomes have garnered extensive attention as therapeutic agents and early diagnostic markers in neurodegenerative disease research.Exosomes are small and can effectively cross the blood-brain barrier,allowing them to target deep brain lesions.Recent studies have demonstrated that exosomes derived from different cell types may exert therapeutic effects by regulating the expression of various inflammatory cytokines,mRNAs,and disease-related proteins,thereby halting the progression of neurodegenerative diseases and exhibiting beneficial effects.However,exosomes are composed of lipid bilayer membranes and lack the ability to recognize specific target cells.This limitation can lead to side effects and toxicity when they interact with non-specific cells.Growing evidence suggests that surface-modified exosomes have enhanced targeting capabilities and can be used as targeted drug-delivery vehicles that show promising results in the treatment of neurodegenerative diseases.In this review,we provide an up-to-date overview of existing research aimed at devising approaches to modify exosomes and elucidating their therapeutic potential in neurodegenerative diseases.Our findings indicate that exosomes can efficiently cross the blood-brain barrier to facilitate drug delivery and can also serve as early diagnostic markers for neurodegenerative diseases.We introduce the strategies being used to enhance exosome targeting,including genetic engineering,chemical modifications(both covalent,such as click chemistry and metabolic engineering,and non-covalent,such as polyvalent electrostatic and hydrophobic interactions,ligand-receptor binding,aptamer-based modifications,and the incorporation of CP05-anchored peptides),and nanomaterial modifications.Research into these strategies has confirmed that exosomes have significant therapeutic potential for neurodegenerative diseases.However,several challenges remain in the clinical application of exosomes.Improvements are needed in preparation,characterization,and optimization methods,as well as in reducing the adverse reactions associated with their use.Additionally,the range of applications and the safety of exosomes require further research and evaluation. 展开更多
关键词 Alzheimer’s disease cell recognition central nervous system diseases enhanced targeting exosome modification exosome targeting neurodegenerative disease Parkinson’s disease stem cell exosomes stem cell therapy
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Challenges and limitations in assessing mucosal healing in Crohn’s disease:Discrepancies between endoscopic and histologic evaluations
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作者 Arunkumar Krishnan Diptasree Mukherjee 《World Journal of Gastrointestinal Endoscopy》 2025年第3期78-82,共5页
The recent study published by Lee et al examined the discrepancies between endoscopic and histologic evaluations of mucosal inflammation in active ileal Crohn’s disease(CD).While this research contributes to our unde... The recent study published by Lee et al examined the discrepancies between endoscopic and histologic evaluations of mucosal inflammation in active ileal Crohn’s disease(CD).While this research contributes to our understanding of the limitations of current biopsy protocols,it raises several concerns about the generalizability of its findings,sample size,and methodology.One major limitation was the exclusion of patients with ileal strictures,ileostomies,or J-pouches,which reduced the applicability of the results to the wider CD population.Furthermore,the biopsy protocol's focus on single biopsies from specific locations may inadequately capture the patchy inflammation characteristic of CD.The study also uses histologic indices primarily developed for ulcerative colitis,which may not be suitable for assessing CD.It is recommended that multi-center studies be conducted and histologic indices specific to CD be developed to improve the relevance of future research.Additionally,researchers should consider the influence of treatment regimens on the findings.Addressing these limitations would enhance the clinical significance of the study and inform better diagnostic and therapeutic approaches for CD. 展开更多
关键词 Endoscopy Inflammatory bowel disease Crohn’s disease COLONOsCOPY HIsTOLOGY DIsCORDANCE Biopsy Imaging-histological discordance
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review 被引量:1
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging BALANCE encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography sOMATOsENsORY VEsTIBULAR visual
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Lion Eyes the Stars Senegal joins Chinese lunar station programme,a&rming its space ambitions
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作者 《ChinAfrica》 2025年第11期46-47,共2页
Space was once a distant dream for African nations like Senegal.But that is changing fast.Today,space is emerging as a strategic frontier for the continent,with 22 countries including Senegal now operating national sp... Space was once a distant dream for African nations like Senegal.But that is changing fast.Today,space is emerging as a strategic frontier for the continent,with 22 countries including Senegal now operating national space agencies.Senegal launched its own agency,the Senegalese Space Study Agency(ASES),in March 2023.The recent inauguration of the African Space Agency’s headquarters in Cairo,Egypt,marks a new chapter in Africa’s rising ambitions beyond Earth.Tasked with coordinating national programmes,the agency seeks to drive economic and social development through space technologies while promoting scientific cooperation both within Africa and internationally. 展开更多
关键词 coordinating national programmesthe space agenciessenegal space ambitions senegal african space agency s senegalese space study agency ases sPACE space agencies
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Transplantation of human hepatocytes into tolerized genetically immunocompetent rats 被引量:23
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作者 EdwinC.Ouyang CatherineH.Wu +2 位作者 CherieWalton KittichaiPromrat GeorgeY.Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期324-330,共7页
AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human... AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human hepatocytes was established by injection of primary human hepatocytes or Huh7 human hepatoma cells into the peritoneal cavities of fetal rats. Corresponding cells were subsequently transplanted into newborn rats via intrasplenic injection within 24h after birth. RESULTS: Mixed lymphocyte assays showed that spleen cells from non-tolerized rats were stimulated to proliferate when exposed to human hepatocytes, while cells from tolerized rats were not. Injections made between 15 d and 17 d of gestation produced optimal tolerization. Transplanted human hepatocytes in rat livers were visualized by immunohistochemical staining of human albumin. By dot blotting of genomic DNA in livers of tolerized rats 16 weeks after hepatocyte transplantation, it was found that approximately 2.5 X 10(5) human hepatocytes survived per rat liver. Human albumin mRNA was detected in rat livers by RT-PCR for 15 wk, and human albumin protein was also detectable in rat serum. CONCLUSION: Tolerization of an immuno-competent rat can permit transplantation, and survival of functional human hepatocytes. 展开更多
关键词 ALBUMINs Animals Cell Line Transformed Disease Models Animal Female Gene Expression Graft survival Hepatitis HEPATOBLAsTOMA Hepatocytes Humans Immune Tolerance IMMUNOCOMPETENCE Liver Liver Neoplasms Lymphocyte Culture Test Mixed Microscopy Confocal Pregnancy RNA Messenger RATs Rats sprague-Dawley Research support Non-U.s. Gov't Research support U.s. Gov't P.H.s.
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Recombinant scorpion insectotoxin AaIT kills specifically insect cells but not human cells 被引量:5
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作者 SHENG JIAN JI, FENG LIU, ER Qiu LI, Yu XIAN ZHUThe National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China 《Cell Research》 SCIE CAS CSCD 2002年第2期143-150,共8页
The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was ... The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LC50 value of 18.4 microM and 0.70 microM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 microM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3 microM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells. 展开更多
关键词 Amino Acid sequence Animals Base sequence Biological Assay Cell Line Cloning Molecular Dose-Response Relationship Drug Electrophoresis Polyacrylamide Gel Escherichia coli Humans Inhibitory Concentration 50 Insects Molecular sequence Data Peptides Protein structure Tertiary Recombinant Proteins Research support Non-U.s. Gov't scorpion Venoms sequence Analysis Protein sodium Time Factors Tumor Cells Cultured
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Europe’s Strategic Choices and the Future of China-EU Relations
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作者 WU HUIPING 《China Today》 2025年第6期51-53,共3页
While celebrating 50 years of diplomatic ties,China and the EU are deepening their strategic partnership to counter U.S.-China tensions and Europe’s own geopolitical and economic challenges.
关键词 strategic partnership U s China tensions China EU relations strategic choices geopolitical challenges economic challenges deepening their strategic partnership diplomatic ties
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