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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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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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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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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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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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Utilizing Single-cell and Spatial RNA-seq databasE for Alzheimer’s Disease(ssREAD)in hypothesis-driven queries
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作者 Diana Acosta Cankun Wang +1 位作者 Qin Ma Hongjun Fu 《Neural Regeneration Research》 2026年第2期677-678,共2页
Alzheimer’s disease(AD)is the most common form of dementia.In addition to the lack of effective treatments,there are limitations in diagnostic capabilities.The complexity of AD itself,together with a variety of other... Alzheimer’s disease(AD)is the most common form of dementia.In addition to the lack of effective treatments,there are limitations in diagnostic capabilities.The complexity of AD itself,together with a variety of other diseases often observed in a patient’s history in addition to their AD diagnosis,make deciphering the molecular mechanisms that underlie AD,even more important.Large datasets of single-cell RNA sequencing,single-nucleus RNA-sequencing(snRNA-seq),and spatial transcriptomics(ST)have become essential in guiding and supporting new investigations into the cellular and regional susceptibility of AD.However,with unique technology,software,and larger databases emerging;a lack of integration of these data can contribute to ineffective use of valuable knowledge.Importantly,there was no specialized database that concentrates on ST in AD that offers comprehensive differential analyses under various conditions,such as sex-specific,region-specific,and comparisons between AD and control groups until the new Single-cell and Spatial RNA-seq databasE for Alzheimer’s Disease(ssREAD)database(Wang et al.,2024)was introduced to meet the scientific community’s growing demand for comprehensive,integrated,and accessible data analysis. 展开更多
关键词 sex specific alzheimer s disease ad deciphering molecular mechanisms spatial transcriptomics ssread spatial transcriptomics st Alzheimers disease single cell RNA seq
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Understanding price momentum,market fluctuations,and crashes:insights from the extended Samuelson model
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作者 Qingyuan Han 《Financial Innovation》 2025年第1期1377-1413,共37页
Although momentum strategies result in abnormal profitability,thereby challenging the efficient market hypothesis(EMH),concerns persist regarding their reliability due to their significant volatility and susceptibilit... Although momentum strategies result in abnormal profitability,thereby challenging the efficient market hypothesis(EMH),concerns persist regarding their reliability due to their significant volatility and susceptibility to substantial losses.In this study,we investigate the limitations of these strategies and propose a solution.Our literature review reveals that the volatile profits are due to statistical analyses that assume the persistence of past patterns,leading to unreliable results in out-of-sample scenarios when underlying mechanisms evolve.Statistical analysis,the predominant method in financial economics,often proves inadequate in explaining market fluctuations and predicting crashes.To overcome these limitations,a paradigm shift towards dynamic approaches is essential.Drawing inspiration from three groundbreaking economists,we introduce the extended Samuelson model(ESM),a dynamic model that connects price changes to market participant actions.This paradigm transition uncovers several significant findings.First,timely signals indicate momentum initiations,cessations,and reversals,validated using S&P 500 data from 1999 to 2023.Second,ESM predicts the 1987 Black Monday crash weeks in advance,offering a new perspective on its underlying cause.Third,we classify sequential stock price data into eight distinct market states,including their thresholds for transitions,laying the groundwork for market trend predictions and risk assessments.Fourth,the ESM is shown to be a compelling alternative to EMH,offering potent explanatory and predictive power based on a single,realistic assumption.Our findings suggest that ESM has the potential to provide policymakers with proactive tools,enabling financial institutions to enhance their risk assessment and management strategies. 展开更多
关键词 Momentum strategy Investor behavior Efficient market hypothesis Behavior finance theory Excess demand Market crisis Market microstructure Market maker’s inventory Boom and bust 1987 Black Monday Warren Buffett samuelson’s model Asymmetric information Herding effect Noise trade sENTIMENT Risk assessment
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Maxwell’s Equations as the Basis for Model of Atoms
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作者 Milan Perkovac 《Journal of Applied Mathematics and Physics》 2014年第5期235-251,共17页
A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can... A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can derive Schr&ouml;dinger’s equation, which is the foundation of quantum physics. The equations for energy, momentum, frequency and wavelength of the electromagnetic wave in the atom are derived using the model of atom by analogy with the transmission line. The action constant A0 = (μ0/ε0)1/2s02e2 is a key term in the above mentioned equations. Besides the other well-known constants, the only unknown constant in the last expression is a structural constant of the atom s0. We have found that the value of this constant is 8.277 56 and that it shows up as a link between macroscopic and atomic world. After calculating this constant we get the theory of atoms based on Maxwell’s and Lorentz equations only. This theory does not require knowledge of Planck’s constant h, which is replaced with theoretically derived action constant A0, while the replacement for the fine structure constant α-1 is theoretically derived expression 2s02 = 137.036. So, the structural constant s0 replaces both constants h and α. This paper also defines the stationary states of atoms and shows that the maximal atomic number is equal to Zmax = 137. The presented model of the atoms covers three of the four fundamental interactions, namely the electromagnetic, weak and strong interactions. 展开更多
关键词 Action CONsTANT Fine structure CONsTANT Lecher’s LINE Maxwell’s Equations New ELEMENTs Phase Velocity Planck’s CONsTANT stability of ATOMs standing Waves stationary sTATEs synchronized sTATEs system of the ELEMENTs sTRUCTURAL Coefficient sTRUCTURAL CONsTANT Transmission LINE Undiscovered ELEMENTs
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The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes 被引量:15
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作者 LiaoJH ChenJS 《Cell Research》 SCIE CAS CSCD 2001年第2期89-94,共6页
We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly ... We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis. 展开更多
关键词 Animals Apoptosis Cells Cultured DNA Fragmentation Enzyme Inhibitors Gene Expression Regulation Enzymologic Genes Reporter Genetic Vectors HEPATOCYTEs IMIDAZOLEs MAP Kinase signaling system Mice Mitogen-Activated Protein Kinases Mutation Phosphorylation Plasminogen Activator Inhibitor 1 PYRIDINEs Research support Non-U.s. Gov't TRANsFECTION Transforming Growth Factor beta p38 Mitogen-Activated Protein Kinases
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JTE-522-induced apoptosis in human gastric adenocarinoma cell line AGS cells by caspase activation accompanying cytochrome C release,membrane translocation of Bax and loss of mitochondrial membrane potential 被引量:17
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作者 Hong-Liang Li Xiao-Hong Li Jun-Hua Lü Xian-Da Ren,Department of Pharmacology,Jinan University Pharmacy College,Guangzhou 510632,Guangdong Province,China Dan-Dan Chen,Department of Cardiology,First Affiliated Hospital,Zhongshan University,Guangzhou 510089,Guangdong Province,China Hai-Wei Zhang,Department of Pathology,Jinan University Medical College,Guangzhou 510632,Guangdong Province,China Cun-Chuan Wang,Department of laparoscopic surgery,First Affiliated Hospital,Jinan University Medical College,Guangzhou 510632,Guangdong Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期217-223,共7页
AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (D... AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells. 展开更多
关键词 Adenocarcinoma stomach Neoplasms Amino Acid Chloromethyl Ketones Anti-Inflammatory Agents Non-steroidal Apoptosis BENZENEsULFONATEs CAsPAsEs inhibitors Cyclooxygenase Inhibitors Cysteine Proteinase Inhibitors Cytochrome c Group Enzyme Activation Humans In situ Nick-End Labeling Membrane Potentials Mitochondria OXAZOLEs Proto-Oncogene Proteins Proto-Oncogene Proteins c-bcl-2 Research support Non-U.s. Gov't Tumor Cells Cultured bcl-2-Associated X Protein
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Reduction of tumorigenicity of SMMC-7721 hepatoma cells by vascular endothelial growth factor antisense gene therapy 被引量:33
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作者 Yu Cheng Tang Yu Li Guan Xiang Qian Department of Biochemistry, Shanghai Second Medical University, Shanghai 200025, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期22-27,共6页
AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cass... AIM: To test the hypothesis to block VEGF expression of SMMC-7721 hepatoma cells may inhibit tumor growth using the rat hepatoma model. METHODS: Amplify the 200 VEGF cDNA fragment and insert it into human U6 gene cassette in the reverse orientation transcribing small antisense RNA which could specifically interact with VEGF165, and VEGF121 mRNA. Construct the retroviral vector containing this antisense VEGF U6 cassette and package the replication-deficient recombinant retrovirus. SMMC-7721 cells were transduced with these virus and positive clones were selected with G418. PCR and Southern blot analysis were performed to determine if U6 cassette integrated into the genomic DNA of positive clone. Transfected tumor cells were evaluated for RNA expression by ribonuclease protection assays. The VEGF protein in the supernatant of parental tumor cells and genetically modified tumor cells was determined with ELISA. In vitro and in vivo growth properties of antisense VEGF cell clone in nude mice were analyzed. RESULTS: Restriction enzyme digestion and PCR sequencing verified that the antisense VEGF RNA retroviral vector was successfully constructed.After G418 selection, resistant SMMC-7721 cell clone was picked up. PCR and Southern blot analysis suggested that U6 cassette was integrated into the cell genomic DNA. Stable SMMC-7721 cell clone transduced with U6 antisense RNA cassette could express 200 bp small antisense VEGF RNA and secrete reduced levels of VEGF in culture condition. Production of VEGF by antisense transgene-expressing cells was 65+/-10 ng/L per 10(6) cells, 42045 ng/L per 10(6) cells in sense group and 485+/-30 ng/L per 10(6) cells in the negative control group, (P【 0.05). The antisense-VEGF cell clone appeared phenotypically indistinguishable from SMMC-7721 cells and SMMC-7721 cells transfected sense VEGF. The growth rate of the antisense-VEGF cell clone was the same as the control cells. When S.C. was implanted into nude mice, growth of antisense-VEGF cell lines was greatly inhibited compared with control cells. CONCLUSION: Expression of antisense VEGF RNA in SMMC-7721 cells could decrease the tumorigenicity, and antisense-VEGF gene therapy may be an adjuvant treatment for hepatoma. 展开更多
关键词 Gene Therapy Animals Carcinoma Hepatocellular Cell Division DNA Polymerase III Endothelial Growth Factors Endothelium Vascular Enzyme-Linked Immunosorbent Assay Gene Expression Humans Liver Neoplasms LYMPHOKINEs MICE Mice Nude Neovascularization Pathologic Promoter Regions (Genetics) RNA Antisense Research support Non-U.s. Gov't Transduction Genetic Tumor Cells Cultured Vascular Endothelial Growth Factor A Vascular Endothelial Growth Factors
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Studies on mechanism of Sialy Lewis-X antigen in liver metastases of human colorectal carcinoma 被引量:19
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作者 Xiao Wei Li~1 Yan Qing Ding~1 Jun Jie Cai~1 Shao Qing Yang~2 Lian Bing An~3 Dong Fang Qiao~3 ~1Department of Pathology,Nanfang Hospital of the First Military Medical University,Guangzhou 510515,Guangdong Province,China ~2The Northern Hospital of PLA,Shenyang 110015,Liaoning Province,China ~3Department of Electronmicroscopy,First Military Medical University,Guangzhou 510515,Gangdong Province,ChinaDr.Xiao Wei Li graduated from the First Military Medical University with a MM degree in 1999.Physician in Charge of pathology,having 6 papers published. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期425-430,共6页
INTRODUCTIONSialyl Lewis-X antigen ,correlated with carcinoma, is a group of carbohydrate antigen containing oligosaccharide expressed of embryonic tisue and glycoproteins on cell surface of embryonic tissue[1].The SL... INTRODUCTIONSialyl Lewis-X antigen ,correlated with carcinoma, is a group of carbohydrate antigen containing oligosaccharide expressed of embryonic tisue and glycoproteins on cell surface of embryonic tissue[1].The SLeX antigen located on cell surface is synthesized principally by two enzymes ,al ,3fucosyltransfrease and a2, 3sialyctransferase.In adults ,SLeX antigen is expressed principally on the surfaces of granulocytic cells and some tumor cells . 展开更多
关键词 Animals Antibodies Monoclonal Antigens CD15 Cell Adhesion Colorectal Neoplasms E-selectin Endothelium Vascular Flow Cytometry HT29 Cells Humans Immunohistochemistry In situ Hybridization Liver Neoplasms MICE Mice Inbred BALB C Mice Nude Microscopy Electron Microscopy Electron scanning N-Acetylneuraminic Acid RNA Messenger Research support Non-U.s. Gov't Tumor Cells Cultured Umbilical Veins
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Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR 被引量:14
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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 Alzheimer’s 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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Chemical exchange saturation transfer MRI for neurodegenerative diseases:An update on clinical and preclinical studies
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作者 Ahelijiang Saiyisan Shihao Zeng +4 位作者 Huabin Zhang Ziyan Wang Jiawen Wang Pei Cai Jianpan Huang 《Neural Regeneration Research》 2026年第2期553-568,共16页
Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been... Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been extensively studied for diagnosing malignancy and stroke.In recent years,the emerging exploration of chemical exchange saturation transfer magnetic resonance imaging for detecting pathological changes in neurodegenerative diseases has opened up new possibilities for early detection and repetitive scans without ionizing radiation.This review serves as an overview of chemical exchange saturation transfer magnetic resonance imaging with detailed information on contrast mechanisms and processing methods and summarizes recent developments in both clinical and preclinical studies of chemical exchange saturation transfer magnetic resonance imaging for Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and Huntington’s disease.A comprehensive literature search was conducted using databases such as PubMed and Google Scholar,focusing on peer-reviewed articles from the past 15 years relevant to clinical and preclinical applications.The findings suggest that chemical exchange saturation transfer magnetic resonance imaging has the potential to detect molecular changes and altered metabolism,which may aid in early diagnosis and assessment of the severity of neurodegenerative diseases.Although promising results have been observed in selected clinical and preclinical trials,further validations are needed to evaluate their clinical value.When combined with other imaging modalities and advanced analytical methods,chemical exchange saturation transfer magnetic resonance imaging shows potential as an in vivo biomarker,enhancing the understanding of neuropathological mechanisms in neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease chemical exchange saturation transfer Huntington’s disease magnetic resonance imaging molecular imaging multiple sclerosis neurodegenerative disease Parkinson’s disease
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Astrocyte glycolysis in Alzheimer’s disease:When the stars burn out
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作者 Simon M.Bell Heather Mortiboys 《Neural Regeneration Research》 2026年第3期1130-1131,共2页
Alzheimer’s disease(AD)is the most common form of dementia characterized pathologically by the deposition of amyloid plaques and hyperphosphorylated tau containing neurofibrillary tangles.The disease presents clinica... Alzheimer’s disease(AD)is the most common form of dementia characterized pathologically by the deposition of amyloid plaques and hyperphosphorylated tau containing neurofibrillary tangles.The disease presents clinically with progressive memory loss and disruption of cognitive function.Currently,there is no cure for AD;recent advances in the therapeutics aimed at clearing the amyloid protein from the brain have led to potential disease stabilization,however,this does not prevent eventual disease progression(Cummings et al.,2024). 展开更多
关键词 hyperphosphorylated tau containing neurofibrillary tanglesthe memory loss alzheimer s disease ad Alzheimers disease AsTROCYTE GLYCOLYsIs amyloid protein amyloid plaques
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Sesquiterpene lactones as potential drugs treating nerve injury
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作者 Philipp Gobrecht Marco Leibinger Dietmar Fischer 《Neural Regeneration Research》 2026年第2期671-672,共2页
Traumatic axonal lesions of peripheral nerves disrupt neuronal connections with their targets,resulting in the loss of motor and sensory functions.Despite the peripheral nervous system’s capacity for axonal regrowth,... Traumatic axonal lesions of peripheral nerves disrupt neuronal connections with their targets,resulting in the loss of motor and sensory functions.Despite the peripheral nervous system’s capacity for axonal regrowth,this may lead to permanent impairements resulting in a loss of quality of life and a high socioeconomic burden. 展开更多
关键词 traumatic axonal lesions peripheral nervous system s axonal regrowththis permanent impairements nerve injury peripheral nerves disrupt neuronal connections sesquiterpene lactones
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