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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron 认领 引用
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 Electron Positron Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein Gordon Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction Repulsion Shell Theorem Ehrenfest Virial Normalization Harmonic Oscillator
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Establishing minimum clinically important difference values for the Patient-Reported Outcomes Measurement Information System Physical Function, hip disability and osteoarthritis outcome score for joint reconstruction, and knee injury and osteoarthritis out 认领 引用 被引量:3
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作者 Man Hung Jerry Bounsanga +1 位作者 Maren W Voss Charles L Saltzman 《World Journal of Orthopedics》 2018年第3期41-49,共9页
AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint condition... AIM To establish minimum clinically important difference(MCID) for measurements in an orthopaedic patient population with joint disorders.METHODS Adult patients aged 18 years and older seeking care for joint conditions at an orthopaedic clinic took the Patient-Reported Outcomes Measurement Information System Physical Function(PROMIS~? PF) computerized adaptive test(CAT), hip disability and osteoarthritis outcome score for joint reconstruction(HOOS JR), and the knee injury and osteoarthritis outcome score for joint reconstruction(KOOS JR) from February 2014 to April 2017. MCIDs were calculated using anchorbased and distribution-based methods. Patient reports of meaningful change in function since their first clinic encounter were used as an anchor.RESULTS There were 2226 patients who participated with a mean age of 61.16(SD = 12.84) years, 41.6% male, and 89.7% Caucasian. Mean change ranged from 7.29 to 8.41 for the PROMIS~? PF CAT, from 14.81 to 19.68 for the HOOS JR, and from 14.51 to 18.85 for the KOOS JR. ROC cut-offs ranged from 1.97-8.18 for the PF CAT, 6.33-43.36 for the HOOS JR, and 2.21-8.16 for the KOOS JR. Distribution-based methods estimated MCID values ranging from 2.45 to 21.55 for the PROMIS~? PF CAT; from 3.90 to 43.61 for the HOOS JR, and from 3.98 to 40.67 for the KOOS JR. The median MCID value in the range was similar to the mean change score for each measure and was 7.9 for the PF CAT, 18.0 for the HOOS JR, and 15.1 for the KOOS JR.CONCLUSION This is the first comprehensive study providing a wide range of MCIDs for the PROMIS? PF, HOOS JR, and KOOS JR in orthopaedic patients with joint ailments. 展开更多
关键词 Hhip disability and osteoarthritis outcome score for joint reconstruction Patient-Reported Outcomes Measurement Information System Physical Function Knee injury and osteoarthritis outcome score for joint reconstruction Minimum clinically important difference Joint Physical function Minimum detectable change Arthroplasty Orthopaedics Clinical outcomes
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Functional near-infrared spectroscopy:Systematic mapping of abnormal brain function features in neurological disorders 认领 引用 被引量:1
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作者 Yunjie Li Yangyang Feng +6 位作者 Xia Liu Ruochao Yuan Shiling Chen Jingyi Wang Chao Pan Gaigai Li Zhouping Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第10期4506-4522,共17页
Functional near-infrared spectroscopy quantifies cerebral hemodynamic signals by capturing oxygenation-dependent changes in hemoglobin in a noninvasive,portable,and ecologically valid manner,providing a unique insight... Functional near-infrared spectroscopy quantifies cerebral hemodynamic signals by capturing oxygenation-dependent changes in hemoglobin in a noninvasive,portable,and ecologically valid manner,providing a unique insight into neurovascular coupling.However,functional imaging biomarkers with high ecological validity for neurological disorders such as stroke,Parkinson's disease,dementia,amyotrophic lateral sclerosis,epilepsy,spinal cord injury,and traumatic brain injury are lacking,limiting the mechanistic understanding,treatment evaluations,and individualized interventions.The aim of this review is to systematically summarize evidence from the past decade on the use of functional near-infrared spectroscopy under the aforementioned conditions,synthesize its value for revealing neural mechanisms and assessing therapeutic responses,and identify current technical bottlenecks and future directions for advancement.Collectively,the findings demonstrate that functional near-infrared spectroscopy possesses substantial and far-reaching potential for uncovering the neural mechanisms underlying disease and for evaluating treatment-induced changes in brain function.Equipped with wearable probes,functional near-infrared spectroscopy can continuously and noninvasively monitor brain activity in naturalistic environments for extended periods,thereby overcoming the limitations of conventional imaging modalities that can only acquire data under restricted settings.This capability can furnish unprecedented objective neuroimaging evidence for neuroregenerative therapy research.Moreover,the portability of functional near-infrared spectroscopy allows it to be integrated into neurofeedback training systems:hemoglobin signals can be fed back to participants within milliseconds,enabling targeted,individualized,closed-loop modulation of brain function and considerably expanding the scope of hemodynamicsbased neurofeedback.When combined with other brain function assays(such as electroencephalography)and intervention techniques(such as transcranial magnetic stimulation and transcranial direct current stimulation),functional near-infrared spectroscopy also supplies high-temporal-resolution hemodynamic information,laying a critical foundation for the construction of high-precision noninvasive brain–computer interfaces,real-time cognitivestate decoding,and adaptive neuromodulation.Admittedly,almost all existing functional near-infrared spectroscopy studies are still observational and have small sample sizes,short follow-ups,and insufficient controls—shortcomings that together produce low-grade evidence.Therefore,there is still a significant gap before clinical translation can be achieved.Technically,the limited penetration depth of functional near-infrared spectroscopy restricts sampling to the superficial cortex,leaving deep nuclei largely unreachable.In addition,no consensus exists across devices regarding optode layout,light-source choice,motion-artifact correction,or analytical pipelines,creating pronounced heterogeneity that undermines reproducibility.With artificial intelligence and big data analytics advancing rapidly,functional near-infrared spectroscopy embedded within multimodal fusion frameworks is now poised to systematically map aberrant brain function signatures of neurological disorders,identify pathological regions suitable for targeted intervention,and provide real-time assessments of functional changes produced by neuroregenerative therapies. 展开更多
关键词 biomarkers brain mapping clinical translational application functional connectivity functional near-infrared spectroscopy multimodal fusion nervous system diseases neuroimaging neuroregenerative therapy neurovascular coupling
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Paired associative stimulation improves synaptic plasticity and functional outcomes after cerebral ischemia 认领 引用 被引量:7
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作者 Yan Hu Tie-Cheng Guo +2 位作者 Xiang-Yu Zhang Jun Tian Yin-Shan Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第11期1968-1976,共9页
Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulati... Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulation on the excitability of the cerebral cortex can vary according to the time interval between the transcranial magnetic stimulation and peripheral nerve stimulation. We established a model of cerebral ischemia in rats via transient middle cerebral artery occlusion. We administered paired associative stimulation with a frequency of 0.05 Hz 90 times over 4 weeks. We then evaluated spatial learning and memory using the Morris water maze. Changes in the cerebral ultra-structure and synaptic plasticity were assessed via transmission electron microscopy and a 64-channel multi-electrode array. We measured mRNA and protein expression levels of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 in the hippocampus using a real-time polymerase chain reaction and western blot assay. Paired associative stimulation treatment significantly improved learning and memory in rats subjected to cerebral ischemia. The ultra-structures of synapses in the CA1 area of the hippocampus in rats subjected to cerebral ischemia were restored by paired associative stimulation. Long-term potentiation at synapses in the CA3 and CA1 regions of the hippocampus was enhanced as well. The protein and mRNA expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 increased after paired associative stimulation treatment. These data indicate that paired associative stimulation can protect cog-nition after cerebral ischemia. The observed effect may be mediated by increases in the mRNA and protein expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1, and by enhanced synaptic plasticity in the CA1 area of the hippocampus. The animal experiments were approved by the Animal Ethics Committee of Tongji Medical College, Huazhong University of Science & Technology, China(approval No. TJ-A20151102) on July 11, 2015. 展开更多
关键词 cerebral ischemia paired associative stimulation cognitive function long-term potentiation synaptic plasticity Morris water maze synaptic structure N-methyl-D-aspartic acid receptor brain-derived neurotrophic factor multi-electrode array neural regeneration
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Topical administration of GLP-1 eyedrops improves retinal ganglion cell function by facilitating presynaptic GABA release in early experimental diabetes 认领 引用 被引量:4
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作者 Yu-Qi Shao Yong-Chen Wang +6 位作者 Lu Wang Hang-Ze Ruan Yun-Feng Liu Ti-Hui Zhang Shi-Jun Weng Xiong-Li Yang Yong-Mei Zhong 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第2期800-810,共11页
Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission ... Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission are associated with pathophysiological and neurodegenerative disorders,whereas glucagon-like peptide-1 has demonstrated neuroprotective effects.However,it is not yet clear whether diabetes causes alterations in inhibitory input to retinal ganglion cells and whether and how glucagon-like peptide-1 protects against neurodegeneration in the diabetic retina through regulating inhibitory synaptic transmission to retinal ganglion cells.In the present study,we used the patch-clamp technique to recordγ-aminobutyric acid subtype A receptor-mediated miniature inhibitory postsynaptic currents in retinal ganglion cells from streptozotocin-induced diabetes model rats.We found that early diabetes(4 weeks of hyperglycemia)decreased the frequency of GABAergic miniature inhibitory postsynaptic currents in retinal ganglion cells without altering their amplitude,suggesting a reduction in the spontaneous release ofγ-aminobutyric acid to retinal ganglion cells.Topical administration of glucagon-like peptide-1 eyedrops over a period of 2 weeks effectively countered the hyperglycemia-induced downregulation of GABAergic mIPSC frequency,subsequently enhancing the survival of retinal ganglion cells.Concurrently,the protective effects of glucagon-like peptide-1 on retinal ganglion cells in diabetic rats were eliminated by topical administration of exendin-9-39,a specific glucagon-like peptide-1 receptor antagonist,or SR95531,a specific antagonist of theγ-aminobutyric acid subtype A receptor.Furthermore,extracellular perfusion of glucagon-like peptide-1 was found to elevate the frequencies of GABAergic miniature inhibitory postsynaptic currents in both ON-and OFF-type retinal ganglion cells.This elevation was shown to be mediated by activation of the phosphatidylinositol-phospholipase C/inositol 1,4,5-trisphosphate receptor/Ca2+/protein kinase C signaling pathway downstream of glucagon-like peptide-1 receptor activation.Moreover,multielectrode array recordings revealed that glucagon-like peptide-1 functionally augmented the photoresponses of ON-type retinal ganglion cells.Optomotor response tests demonstrated that diabetic rats exhibited reductions in visual acuity and contrast sensitivity that were significantly ameliorated by topical administration of glucagon-like peptide-1.These results suggest that glucagon-like peptide-1 facilitates the release ofγ-aminobutyric acid onto retinal ganglion cells through the activation of glucagon-like peptide-1 receptor,leading to the de-excitation of retinal ganglion cell circuits and the inhibition of excitotoxic processes associated with diabetic retinopathy.Collectively,our findings indicate that theγ-aminobutyric acid system has potential as a therapeutic target for mitigating early-stage diabetic retinopathy.Furthermore,the topical administration of glucagon-like peptide-1 eyedrops represents a non-invasive and effective treatment approach for managing early-stage diabetic retinopathy. 展开更多
关键词 diabetic retinopathy glucagon-like peptide-1 inhibitory synaptic transmission miniature inhibitory postsynaptic currents neurodegeneration neuroprotection patch-clamp recording protein kinase C signaling pathway visual function
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Ab initio density functional theory approach to warm dense hydrogen:From density response to electronic correlations 认领 引用 被引量:1
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作者 Zhandos A.Moldabekov Xuecheng Shao +5 位作者 Hannah M.Bellenbaum Cheng Ma Wenhui Mi Sebastian Schwalbe Jan Vorberger Tobias Dornheim 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2026年第2期14-20,共7页
Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confinement fusion applications.The workhorse ... Understanding the properties of warm dense hydrogen is of key importance for the modeling of compact astrophysical objects and to understand and further optimize inertial confinement fusion applications.The workhorse of warm dense matter theory is thermal density functional theory(DFT),which,however,suffers from two limitations:(i)its accuracy can depend on the utilized exchange-correlation functional,which has to be approximated,and(ii)it is generally limited to single-electron properties such as the density distribution.Here,we present a new ansatz combining time-dependent DFT results for the dynamic structure factor See(q,ω)with static DFT results for the density response.This allows us to estimate the electron-electron static structure factor See(q)of warm dense hydrogen with high accuracy over a broad range of densities and temperatures.In addition to its value for the study of warm dense matter,our work opens up new avenues for the future study of electronic correlations exclusively within the framework of DFT for a host of applications. 展开更多
关键词 thermal density functional theory dft whichhoweversuffers understanding properties warm dense hydrogen thermal density functional theory understand further optimize inertial confinement fusion applicationsthe warm dense matter theory electronic correlations warm dense hydrogen density functional theory
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A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study 认领 引用 被引量:3
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作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
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A comparison of piecewise cubic Hermite interpolating polynomials,cubic splines and piecewise linear functions for the approximation of projectile aerodynamics 认领 引用 被引量:9
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作者 C.A.Rabbath D.Corriveau 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期741-757,共17页
Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and repr... Modelling and simulation of projectile flight is at the core of ballistic computer software and is essential to the study of performance of rifles and projectiles in various engagement conditions.An effective and representative numerical model of projectile flight requires a relatively good approximation of the aerodynamics.The aerodynamic coefficients of the projectile model should be described as a series of piecewise polynomial functions of the Mach number that ideally meet the following conditions:they are continuous,differentiable at least once,and have a relatively low degree.The paper provides the steps needed to generate such piecewise polynomial functions using readily available tools,and then compares Piecewise Cubic Hermite Interpolating Polynomial(PCHIP),cubic splines,and piecewise linear functions,and their variant,as potential curve fitting methods to approximate the aerodynamics of a generic small arms projectile.A key contribution of the paper is the application of PCHIP to the approximation of projectile aerodynamics,and its evaluation against a set of criteria.Finally,the paper provides a baseline assessment of the impact of the polynomial functions on flight trajectory predictions obtained with 6-degree-of-freedom simulations of a generic projectile. 展开更多
关键词 Aerodynamic coefficients Piecewise polynomial functions Cubic splines Curve fitting Piecewise linear functions Piecewise cubic Hermite interpolating polynomial Projectile modelling and simulation Fire control inputs Precision Ballistic computer software
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Monitoring Zenithal Total Delays over the three different climatic zones from IGS GPS final products:A comparison between the use of the VMF1 and GMF mapping functions 认领 引用 被引量:4
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作者 Benachour Labib Jianguo Yan +2 位作者 Jean-Pierre Barriot Fangzhao Zhang Peng Feng 《Geodesy and Geodynamics》 2019年第2期93-99,共7页
The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. ... The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. In this study, we investigate if there is a systematic difference coming from the choice between the Vienna Mapping Function 1(VMF1) and the Global Mapping Function(GMF) for the modeling of Zenith Total Delay(ZTD) estimates, as well as the Integrated Precipitable Water Vapor(IPWV) estimates that are deduced from them. As ZTD estimates cannot be fully separated from coordinate estimates, we also investigated the coordinate repeatability between subsequent measurements.For this purpose, we monitored twelve GNSS stations on a global scale, for each of the three climatic zones(polar, mid-latitudes and tropical), with four stations on each zone. We used an automated processing based on the Bernese GNSS Software Version 5.2 by applying the Precise Point Positioning(PPP)approach, L3 Ionosphere-free linear combination, 7 cutoff elevation angle and 2 h sampling. We noticed an excellent agreement with the ZTD estimates and coordinate repeatability for all the stations w.r.t to CODE(the Center for Orbit Determination in Europe) and USNO(US Naval Observatory) products, except for the Antarctic station(Davis) which shows systematic biases for the GMF related results. As a final step, we investigated the effect of using two mapping functions(VMF1 and GMF) to estimate the IPWV,w.r.t the IPWV estimates provided by the Integrated Global Radiosonde Archive(IGRA). The GPS-derived IPWV estimates are very close to the radiosonde-derived IPWV estimates, except for one station in the tropics(Tahiti). 展开更多
关键词 International GNSS Service (IGS) Vienna Mapping Function 1 (VMF1) Global Mapping Function (GMF) Precise Point Positioning (PPP) Zenith Total Delay (ZTD) Zenith Wet Delay (ZWD) Integrated Precipitable Water Vapor (IPWV)
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Intermittent hypoxic perconditioning improves cognitive function in a mouse model of vascular cognitive impairment and dementia with comorbidities by recovering cerebral blood flow 认领 引用
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作者 Feiyang Jin Zhengming Tian +9 位作者 Yuying Guan Yuning Li Yakun Gu Mengyuan Guo Qianqian Shao Yingxia Liu Xiuhai Guo Zhenzhen Quan Jia Liu Xunming Ji 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第6期2415-2424,共10页
Vascular cognitive impairment and dementia is a debilitating neurological disorder caused by chronic cerebral hypoperfusion,for which no effective causative treatments are currently available.Intermittent hypoxia has ... Vascular cognitive impairment and dementia is a debilitating neurological disorder caused by chronic cerebral hypoperfusion,for which no effective causative treatments are currently available.Intermittent hypoxia has been shown to enhance cerebral blood flow in mice,but its efficacy in a model of vascular cognitive impairment and dementia remains unclear.In this study,we established a mouse model of vascular cognitive impairment and dementia by bilateral carotid artery stenosis.Intermittent hypoxia was induced before and after this stenosis.We found that intermittent hypoxia increased cerebral blood flow,oxygen saturation,and microcirculation in the prefrontal cortex and hippocampus in the model mice,without causing neurovascular damage.Additionally,intermittent hypoxia significantly improved cognitive function in the mouse model of vascular cognitive impairment and dementia,with perconditioning showing greater efficacy than preconditioning.Improvements in cerebral microcirculation and blood flow were positively correlated with cognitive recovery.Even in a mouse model of vascular cognitive impairment and dementia with comorbidities induced by a high-fat,high-fructose diet,intermittent hypoxic perconditioning demonstrated protective effects on cognitive function.Proteomic analysis indicated that mitochondrial protection is a key mechanism,particularly through upregulating NDUFB8 expression and increasing the activity of mitochondrial complex I.These findings suggest that intermittent hypoxia is a potential non-invasive strategy for the prevention and treatment of vascular cognitive impairment and dementia. 展开更多
关键词 bilateral carotid artery stenosis cerebrovascular microcirculation chronic cerebral hypoperfusion cognitive function high fat-high fructose diet hippocampus intermittent hypoxia mitochondrial respiratory chain prefrontal cortex vascular cognitive impairment and dementia
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Activin A enhances neurofunctional recovery following traumatic spinal cord injury by inhibiting autophagy 认领 引用
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作者 Liqun Yu Zhaoyang Yin +12 位作者 Ruiqi Huang Zhibo Liu Yuchen Liu Xinxin Zheng Simin Song Zhaojie Wang Xiaolie He Yuxin Bai Li Yang Xu Xu Bairu Chen Jian Yin Yanjing Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第6期2485-2494,共10页
In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neur... In the early stages of traumatic spinal cord injury,extensive accumulation of autophagosomes creates a neurotoxic microenvironment,exacerbating neuronal cell death and worsening tissue damage,ultimately hindering neurofunctional recovery.Activin A is a critical growth factor necessary for the development of the embryonic nervous system and for maintaining neuronal function in the adult cerebral cortex.It can inhibit excessive autophagy in ischemic stroke to reduce neuronal damage.However,the specific mechanism through which Activin A functions in the spinal cord remains poorly understood.In this study,we administered different concentrations of Activin A to neural stem cells from the spinal cord and found that Activin A stimulated the proliferation and neuronal differentiation of neural stem cells.Then,we established an in vitro oxidative stress model by using hydrogen peroxide to stimulate the neural stem cells-induced neurons.We found that Activin A could reduce apoptosis caused by oxidative stress.Subsequently,we treated a mouse model of spinal cord contusion with intrathecal injection of Activin A.Behavioral and electrophysiological results showed that Activin A promoted recovery of motor function and reconstruction of neural circuits in the model mice.Finally,RNA sequencing indicated that Activin A inhibited autophagy by activating the PI3K/AKT/mTOR pathway and upregulating the expression of synaptogenesis-related factor Sema3A in the spinal cord.These results suggest that Activin A may mediate the excessive autophagic response after spinal cord injury,promote the reconstruction of damaged neural circuits,and restore neurological function in the injured spinal cord. 展开更多
关键词 Activin A autophagy cell differentiation motor function recovery neural regeneration neural stem cell neuroprotection phosphoinositide 3-kinase/protein kinase B pathway spinal cord injury transforming growth factor-βsuperfamily
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Dynamic characterization of pathological and functional deterioration in a mouse model of optic neuritis related to neuromyelitis optica spectrum disorder 认领 引用
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作者 Xiayin Yang Shi-Qi Yao +1 位作者 Henry Ho-Lung Chan Shaoying Tan 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第8期3870-3880,共11页
Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disord... Neuromyelitis optica spectrum disorder-related optic neuritis involves various cellular responses to inflammation and degeneration.In most patients,the primary mechanism underlying neuromyelitis optica spectrum disorder-related optic neuritis is the interaction of aquaporin-4 antibodies with the aquaporin-4 protein present on astrocytes within posterior optic nerve.This binding subsequently initiates a cascade of events leading to secondary demyelination of the optic nerve,ultimately culminating in optic nerve degeneration.Earlier studies on this disorder primarily used systemic-induced animal models,which often require prior activation of a systemic immune response.This can result in primary demyelination of the optic nerve,complicating the interpretation of experimental results.Such methodologies hinder the ability to isolate immune responses triggered by specific antibodies.Additionally,the lack of a detailed profile of disease progression over time limits our capacity to identify potential intervention windows.Therefore,constructing a targeted optic neuritis animal model induced by specific antibodies and elucidate the disease progression arecrucial for exploring the mechanisms underlying neuromyelitis optica spectrum disorder-related optic neuritis.In this study,specific antibodies against aquaporin-4 were precisely injected into the retrobulbar optic nerve of mice to induce a targeted inflammatory response in the posterior optic nerve,resulting in a more representative mouse model of neuromyelitis optica spectrum disorder-related optic neuritis than current models.The progression of the disease was then dynamically observed from both histological and functional perspectives over the course of 1 month following the induction of inflammation.By the first week,astrocytes were damaged,as evidenced by the loss of aquaporin-4 and glial fibrillary acidic protein,the activation of microglia,and the upregulation of microglia-related cytokines,including tumor necrosis factor,interleukin-6,interleukin-1β,C-X-C motif ligand 10,and brain-derived neurotrophic factor.Starting from the second week,there were signs of optic nerve demyelination and significant damage to axonal fibers and retinal ganglion cell bodies.Visual-evoked potentials and dark adaptation threshold responses in electroretinogram both indicated dysfunction in the visual pathway and retina,while optical coherence tomography revealed thinning of the retinal nerve fiber layer in live mice.In summary,in this study we conducted a dynamic exploration of the occurrence and progression of neuromyelitis optica spectrum disorder-related optic neuritis triggered by specific antibodies.Our results show pathological changes at various stages and correlate histological and molecular alterations with in vivo structural and functional deterioration.The findings from this study lay an important foundation for further research on neuromyelitis optica spectrum disorder-related optic neuritis. 展开更多
关键词 animal model aquaporin-4 immunoglobulin G dynamic profile electroretinogram functional deterioration in vivo retinal structural scan neuromyelitis optica spectrum disorder-related optic neuritis optic neuritis pathology visual-evoked potential
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 认领 引用 被引量:4
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 angiogenesis apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation microglia motor function spinal cord injury vascular endothelial growth factor
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Periodontitis pathogen Porphyromonas gingivalis promotes chronic obstructive pulmonary disease via affecting neutrophils chemotaxis and function 认领 引用 被引量:1
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作者 Luyao Zhang Huan Tian +4 位作者 Yuanyuan Ma Jing Xu Chang Guo Zuomin Wang Jie Ma 《International Journal of Oral Science》 SCIE CAS CSCD 2026年第1期115-125,共11页
Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microb... Chronic obstructive pulmonary disease(COPD),a disease responsible for early mortality worldwide,is well accepted to be associated with periodontitis epidemiologically.Although both of the diseases are the multi-microbial inflammatory disease,the precise underlying mechanisms by which periodontitis influences the progression of COPD remains largely unknown.Here,we established COPD accompanied with periodontitis mouse models and observed the pronounced progress in pulmonary symptoms and histopathology,cha racterized by poorer respiratory function,thicke ned bronchial walls,and increased neutrophils infiltration in lung tissue.Mechanistically,periodontitis pathogen Porphyromonas gingivalis(P.gingivalis)relocated in the lung through the respiratory tract and LPS from P.gingivalis promoted the secretion of chemokines CXCL2 and G-CSF of alveolar epithelial cells through NF-κB and p38 MAPK pathways to recruit neutrophils.Furthermore,exposure to P.gingivalis of infiltrated neutrophils released matrix metallopeptidase-8(MMP-8)and neutrophil elastase(NE),which aggravated airway inflammation and tissue damage.These findings indicated that periodontitis could exacerbate COPD via its pathogen P.gingivalis,which translocated in the lung and stimulated neutrophil chemotaxis and activation in the lung. 展开更多
关键词 neutrophils chemotaxis pulmonary symptoms histopathology periodontitis neutrophils function chronic obstructive pulmonary disease respiratory function chronic obstructive pulmonary disease copd
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Scalable synthetic peptide hydrogel enables self-organized luminal cavity architecture within hiPSC 3D colonies supporting functional hepatocyte differentiation 认领 引用
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作者 Quan Li Guangyan Qi +12 位作者 Ling Cai Abhishek P.Shrestha Sergio Duarte Yu Shrike Zhang Ali Zarrnapar Tawfik Aboellail Xuming Liu Jianfa Bai Md Sharifur Rahman Bruno Hagenbuch Ming-Shun Chen Anthony Atala Xiuzhi Susan Sun 《Bioactive Materials》 SCIE CSCD 2026年第8期814-830,共17页
Human induced pluripotent stem cells(hiPSCs)possess broad differentiation potential;however,efficient maturation into functional hepatocytes remains challenging,in part because conventional differentiation stra-tegies... Human induced pluripotent stem cells(hiPSCs)possess broad differentiation potential;however,efficient maturation into functional hepatocytes remains challenging,in part because conventional differentiation stra-tegies rely on 2D culture or partially defined 3D systems that fail to recapitulate key developmental microen-vironmental cues.Although 3D culture has been shown to promote hepatic specification and maturation,a fully defined platform that supports the entire differentiation process from hiPSCs in 3D has not been established.Here,we report a scalable synthetic peptide hydrogel(PepGel)platform that enables hiPSCs to self-organize into long-term,proliferative luminal cavity(LC)architectures within 3D colonies(LC-hiPSCs).These LC-hiPSCs exhibited markedly enhanced differentiation efficiency compared to hiPSC aggregates generated via scaffoldfree suspension methods.Using a shear-thinning,self-healing hydrogel configuration optimized for suspension culture,we produced large quantities of LC-hiPSCs and directed their differentiation into PepGel-derived hiPSCderived hepatocyte-like cells(PG-hiHs).PG-hiHs formed polarized,multi-luminal organoid-like structures and exhibited robust expression of hepatocyte-specific genes and proteins,high cytochrome P450 activity,and in vitro metabolic functions comparable to primary human hepatocytes(PHHs).Following live shipment and transplantation into immunocompromised mouse livers,PG-hiHs engrafted efficiently and maintained humanspecific albumin and alpha-1 antitrypsin secretion at PHH-equivalent levels.Furthermore,both LC-hiPSCs and PG-hiHs retained viability,structural organization,and phenotype in complex 3D bioprinted constructs for at least 14 days.Together,this work establishes a fully defined,reproducible,and scalable 3D platform that sup-ports the entire differentiation process,overcoming limitations in hiPSC-derived hepatic maturation and enables physiologically relevant hepatocyte-like tissues for disease modeling,regenerative medicine,and biofabrication. 展开更多
关键词 Synthetic peptide hydrogel Pluripotent stem cells Functional hepatocytes 3D organoids Bioprinting
Neuromodulation technologies improve functional recovery after brain injury:From bench to bedside 认领 引用 被引量:1
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作者 Mei Liu Yijing Meng +4 位作者 Siguang Ouyang Meng’ai Zhai Likun Yang Yang Yang Yuhai Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第2期506-520,共15页
Spontaneous recovery frequently proves maladaptive or insufficient because the plasticity of the injured adult mammalian central nervous system is limited.This limited plasticity serves as a primary barrier to functio... Spontaneous recovery frequently proves maladaptive or insufficient because the plasticity of the injured adult mammalian central nervous system is limited.This limited plasticity serves as a primary barrier to functional recovery after brain injury.Neuromodulation technologies represent one of the fastest-growing fields in medicine.These techniques utilize electricity,magnetism,sound,and light to restore or optimize brain functions by promoting reorganization or long-term changes that support functional recovery in patients with brain injury.Therefore,this review aims to provide a comprehensive overview of the effects and underlying mechanisms of neuromodulation technologies in supporting motor function recovery after brain injury.Many of these technologies are widely used in clinical practice and show significant improvements in motor function across various types of brain injury.However,studies report negative findings,potentially due to variations in stimulation protocols,differences in observation periods,and the severity of functional impairments among participants across different clinical trials.Additionally,we observed that different neuromodulation techniques share remarkably similar mechanisms,including promoting neuroplasticity,enhancing neurotrophic factor release,improving cerebral blood flow,suppressing neuroinflammation,and providing neuroprotection.Finally,considering the advantages and disadvantages of various neuromodulation techniques,we propose that future development should focus on closed-loop neural circuit stimulation,personalized treatment,interdisciplinary collaboration,and precision stimulation. 展开更多
关键词 functional recovery invasive electrical stimulation neuromodulation noninvasive electrical stimulation stroke transcranial magnetic stimulation transcranial photobiomodulation transcranial ultrasound stimulation traumatic brain injury
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Thermodynamic Fit Functions of the Two-Phase Fluid and Critical Exponents 认领 引用 被引量:2
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作者 Albrecht Elsner 《Engineering(科研)》 2014年第12期789-826,共38页
Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series ... Two-phase fluid properties such as entropy, internal energy, and heat capacity are given by thermodynamically defined fit functions. Each fit function is expressed as a temperature function in terms of a power series expansion about the critical point. The leading term with the critical exponent dominates the temperature variation between the critical and triple points. With β being introduced as the critical exponent for the difference between liquid and vapor densities, it is shown that the critical exponent of each fit function depends (if at all) on β. In particular, the critical exponent of the reciprocal heat capacity c﹣1 is α=1-2β and those of the entropy s and internal energy u are?2β, while that of the reciprocal isothermal compressibility?κ﹣1T is γ=1. It is thus found that in the case of the two-phase fluid the Rushbrooke equation conjectured α +?2β + γ=2 combines the scaling laws resulting from the two relations c=du/dT and?κT=dlnρ/dp. In the context with c, the second temperature derivatives of the chemical potential μ and vapor pressure p are investigated. As the critical point is approached, ﹣d2μ/dT2 diverges as c, while?d2p/dT2 converges to a finite limit. This is explicitly pointed out for the two-phase fluid, water (with β=0.3155). The positive and almost vanishing internal energy of the one-phase fluid at temperatures above and close to the critical point causes conditions for large long-wavelength density fluctuations, which are observed as critical opalescence. For negative values of the internal energy, i.e. the two-phase fluid below the critical point, there are only microscopic density fluctuations. Similar critical phenomena occur when cooling a dilute gas to its Bose-Einstein condensate. 展开更多
关键词 Critical Condition U = 0 Critical Opalescence Rushbrooke Equation Thermodynamic Fit Functions for Saturated Water Vapor and Liquid Volumes Vapor Pressure Chemical Potential Entropy Internal Energy Free Energy Heat Capacity
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Davunetide promotes structural and functional recovery of the injured spinal cord by promoting autophagy 认领 引用
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作者 Yituo Chen Rongjie Liu +9 位作者 Wanta Cai Liting Jiang Kongbin Chen Jingwei Shi Junsheng Lou Letian Yu Chenyu Wu Liangliang Yang Kailiang Zhou Wenfei Ni 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第8期3677-3686,共10页
After spinal cord injury,programmed cell death is common.In this context,autophagy plays a crucial role in clearing cellular debris,while necroptosis exacerbates neuroinflammation and further damages neural structures... After spinal cord injury,programmed cell death is common.In this context,autophagy plays a crucial role in clearing cellular debris,while necroptosis exacerbates neuroinflammation and further damages neural structures.The neuroprotective drug davunetide has shown substantial therapeutic effects on brain diseases,but its role in treating spinal cord injury remains unclear.Therefore,the aim of this study was to investigate the effects of davunetide on cell death after spinal cord injury.To do this,we established a mouse model of spinal cord contusion and administered davunetide intranasally daily at a dose of 0.5μg/5μL.Mouse locomotor function was assessed using footprint analysis and Basso Mouse Scale scoring,while the extent of spinal cord injury was evaluated using Masson’s trichrome staining.The expression levels of proteins related to locomotor function and spinal cord injury were analyzed by Western blotting and immunofluorescence staining,and protein-protein interactions were evaluated using immunoprecipitation techniques.Our results demonstrated that davunetide not only reduced the size of the injury area but also promoted the recovery of locomotor function after spinal cord injury.Specifically,davunetide exerted its effects by enhancing autophagy and inhibiting necroptosis.Inhibition of autophagy reversed the protective effects of davunetide on necroptosis.Further investigation revealed that davunetide acted through the SIRT1-FOXO1-TFEB signaling pathway,which is key to its therapeutic effects.These findings suggest the potential of davunetide in the treatment of spinal cord injury and provide valuable insights into the underlying mechanisms.This study offers strong scientific evidence to support the development of new therapeutic strategies for spinal cord injury. 展开更多
关键词 autophagy davunetide locomotor function recovery NAP necroptosis neuron Sirtuin1 spinal cord injury transcription factor EB
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Integration of functional magnetic resonance imaging and artificial intelligence in Alzheimer's disease 认领 引用
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作者 Liqin Yang Yuxin Li +2 位作者 Kuangyu Shi Axel Rominger Ruiqing Ni 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第9期4241-4242,共2页
Alzheimer's disease(AD),the most common cause of dementia,is a progressive neurodegenerative disease characterized by progressive cognitive decline and memory loss.Mild cognitive impairment(MCI)is the prodromal st... Alzheimer's disease(AD),the most common cause of dementia,is a progressive neurodegenerative disease characterized by progressive cognitive decline and memory loss.Mild cognitive impairment(MCI)is the prodromal stage of AD,with a conversion rate of 10%-15%per year and 50%conversion rate longitudinally.The pathological features of AD include the aberrant accumulation of amyloid-βplaques,neurofibrillary tangles formed by hyperphosphorylated tau and synaptic dysfunction(Nussbaumer et al.,2025),all of which have cascading effects on the brain activity of AD patients. 展开更多
关键词 integration artificial intelligence Alzheimers disease functional magnetic resonance imaging synaptic dysfunction nussbaumer hyperphosphorylated tau cognitive decline alzheimers disease ad
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Associations of the Triglyceride-Glucose Index with Kidney Function Decline,Cardiovascular Disease Events,and All-Cause Mortality Across Different Glucose Tolerance Statuses 认领 引用
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作者 Bei-bei Mao Yu-xi Xiang +8 位作者 Pei-qiong Luo Dan-pei Li Ya-ming Guo Xiao-yu Meng Ran-ran Kan Li-meng Pan Yi He Si-yi Wang Xue-feng Yu 《Current Medical Science》 SCIE CAS CSCD 2026年第1期131-142,共12页
Objective This study aimed to investigate the associations of the triglyceride-glucose(TyG)index with kidney function decline,cardiovascular disease(CVD)events,and all-cause mortality across different glucose toleranc... Objective This study aimed to investigate the associations of the triglyceride-glucose(TyG)index with kidney function decline,cardiovascular disease(CVD)events,and all-cause mortality across different glucose tolerance statuses.Methods We analyzed 8,434 participants from the China Cardiometabolic Disease and Cancer Cohort(4C)Study.The primary outcomes were kidney function decline,CVD events,and all-cause mortality.Associations between the TyG index and outcomes were evaluated using binary logistic regression models.Results During a 5-year follow-up,150 participants(1.80%)developed kidney function decline,357(4.30%)experienced CVD events,and 335(4.00%)died from all causes.An elevated TyG index was associated with increased risks of kidney function decline,nonfatal CVD events,and all-cause mortality in the overall population and among participants with diabetes(quartile 4[Q4]vs.quartile 1[Q1]:hazard ratio[HR][95%confidence interval,P-value]=4.97[1.41-31.71,P=0.034],4.63[1.25-30.19,P=0.047],and 4.54[1.70-15.88,P=0.007],respectively).These associations were not statistically significant in participants with normal glucose tolerance or prediabetes.Notably,an elevated TyG index was significantly associated with increased risk of fatal CVD events in the overall population and across all glucose tolerance subgroups,with the strongest association observed in participants with prediabetes rather than diabetes.Conclusions The TyG index is significantly associated with the risks of kidney function decline,CVD events,and all-cause mortality,and these associations differ by glucose tolerance status. 展开更多
关键词 Triglyceride-glucose index Glucose tolerance Kidney function decline Cardiovascular disease All-cause mortality Insulin resistance Diabetes Prediabetes Cohort study
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