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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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Glucocorticoid receptor signaling in the brain and its involvement in cognitive function
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作者 Chonglin Su Taiqi Huang +3 位作者 Meiyu Zhang Yanyu Zhang Yan Zeng Xingxing Chen 《Neural Regeneration Research》 SCIE CAS 2025年第9期2520-2537,共18页
The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an impo... The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and neuroplasticity.The glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic mechanisms.Protein interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive functions.An appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive impairment.Patients with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor expression.This review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive activities.It emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive impairment.This provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders. 展开更多
关键词 brain-derived neurotrophic factor calcium signaling glucocorticoid receptor GLUCOCORTICOID glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders NEUROPLASTICITY stress
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Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases
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作者 Fengcheng Deng Dan Yang +6 位作者 Lingxi Qing Yifei Chen Jilian Zou Meiling Jia Qian Wang Runda Jiang Lihua Huang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3095-3112,共18页
The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enh... The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain axis.The gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine systems.Conversely,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host interactions.This reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological diseases.The coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological diseases.This study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological diseases.Recent pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional disorders.This can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage forms.These findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases. 展开更多
关键词 cyclic adenosine monophosphate emotional disorders gut microbiota neurodegenerative diseases neurological diseases protein kinase A reciprocal regulation signaling pathway STRATEGY THERAPIES
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The dopaminergic system and Alzheimer's disease
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作者 Yuhan Zhang Yuan Liang Yixue Gu 《Neural Regeneration Research》 SCIE CAS 2025年第9期2495-2512,共18页
Alzheimer's disease is a common neurodegenerative disorder in older adults.Despite its prevalence,its pathogenesis remains unclea r.In addition to the most widely accepted causes,which in clude excessive amyloid-b... Alzheimer's disease is a common neurodegenerative disorder in older adults.Despite its prevalence,its pathogenesis remains unclea r.In addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this condition.Dopamine is a crucial catecholaminergic neurotransmitter in the human body.Dopamine-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical manifestations.Howeve r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive impairment.This review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related drugs.The aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options. 展开更多
关键词 adverse drug reaction Alzheimer's disease CATECHOLAMINE dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease NEUROTRANSMITTER signaling pathways traditional Chinese medicine TREATMENT
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Netrin-1 signaling pathway mechanisms in neurodegenerative diseases
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作者 Kedong Zhu Hualong Wang +2 位作者 Keqiang Ye Guiqin Chen Zhaohui Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期960-972,共13页
Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal sur... Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders. 展开更多
关键词 Alzheimer’s disease axon guidance colorectal cancer Netrin-1 receptors Netrin-1 signaling pathways NETRIN-1 neurodegenerative diseases neuron survival Parkinson’s disease UNC5C
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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats
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作者 Ping Zhang Ying Zhu +7 位作者 Pu Chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期93-109,共17页
BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling p... BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal cells.Moreover,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal cells.Cajal cells are the pacemakers of gastrointestinal motility.AIM To investigate the effects of Bifidobacterium lactis(B.lactis)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit pathway.METHODS The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 days.The tail group was given B.lactis BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/day.Hematoxylin&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and PCR.The fecal flora and mucosal flora of rats in each group were detected by 16S rRNA.RESULTS Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic intervention.Simulated microgravity reduced the expressions of SCF and c-kit,and increased the expressions of ERK and P-ERK in the gastric antrum of rats.However,after probiotic intervention,the expressions of SCF and ckit were increased,while the expressions of ERK and P-ERK were decreased,with statistical significance(P<0.05).In addition,simulated microgravity can reduce the operational taxonomic unit(OTU)of the overall intestinal flora of rats,B.lactis BLa80 can increase the OTU of rats,simulated microgravity can reduce the overall richness and diversity of stool flora of rats,increase the abundance of firmicutes in stool flora of rats,and reduce the abundance of Bacteroides in stool flora of rats,most of which are mainly beneficial bacteria.Simulated microgravity can increase the overall richness and diversity of mucosal flora,increase the abundance of Bacteroides and Desulphurides in the rat mucosal flora,and decrease the abundance of firmicutes,most of which are proteobacteria.After probiotics intervention,the overall Bacteroidetes trend in simulated microgravity rats was increased.CONCLUSION B.lactis BLa80 can ameliorate intestinal mucosal injury,regulate intestinal flora,inhibit ERK expression,and activate the SCF/c-kit signaling pathway,which may have a facilitating effect on gastrointestinal motility in simulated microgravity rats. 展开更多
关键词 Simulated microgravity RAT Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway
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Regulator of G protein signaling 6 mediates exercise-induced recovery of hippocampal neurogenesis,learning,and memory in a mouse model of Alzheimer’s disease
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作者 Mackenzie M.Spicer Jianqi Yang +5 位作者 Daniel Fu Alison N.DeVore Marisol Lauffer Nilufer S.Atasoy Deniz Atasoy Rory A.Fisher 《Neural Regeneration Research》 SCIE CAS 2025年第10期2969-2981,共13页
Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rode... Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rodents and improves memory and slows cognitive decline in patients with Alzheimer’s disease.However,the molecular pathways for exercise-induced adult hippocampal neurogenesis and improved cognition in Alzheimer’s disease are poorly understood.Recently,regulator of G protein signaling 6(RGS6)was identified as the mediator of voluntary running-induced adult hippocampal neurogenesis in mice.Here,we generated novel RGS6fl/fl;APP_(SWE) mice and used retroviral approaches to examine the impact of RGS6 deletion from dentate gyrus neuronal progenitor cells on voluntary running-induced adult hippocampal neurogenesis and cognition in an amyloid-based Alzheimer’s disease mouse model.We found that voluntary running in APP_(SWE) mice restored their hippocampal cognitive impairments to that of control mice.This cognitive rescue was abolished by RGS6 deletion in dentate gyrus neuronal progenitor cells,which also abolished running-mediated increases in adult hippocampal neurogenesis.Adult hippocampal neurogenesis was reduced in sedentary APP_(SWE) mice versus control mice,with basal adult hippocampal neurogenesis reduced by RGS6 deletion in dentate gyrus neural precursor cells.RGS6 was expressed in neurons within the dentate gyrus of patients with Alzheimer’s disease with significant loss of these RGS6-expressing neurons.Thus,RGS6 mediated voluntary running-induced rescue of impaired cognition and adult hippocampal neurogenesis in APP_(SWE) mice,identifying RGS6 in dentate gyrus neural precursor cells as a possible therapeutic target in Alzheimer’s disease. 展开更多
关键词 adult hippocampal neurogenesis Alzheimer’s disease dentate gyrus EXERCISE learning/memory neural precursor cells regulator of G protein signaling 6(RGS6)
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Prolonged intermittent theta burst stimulation restores the balance between A_(2A)R-and A_(1)R-mediated adenosine signaling in the 6-hydroxidopamine model of Parkinson's disease
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作者 Milica Zeljkovic Jovanovic Jelena Stanojevic +4 位作者 Ivana Stevanovic Milica Ninkovic Tihomir V.Ilic Nadezda Nedeljkovic Milorad Dragic 《Neural Regeneration Research》 SCIE CAS 2025年第7期2053-2067,共15页
An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)R-mediated signaling,plays a role in the pathogenesis of Parkinson's disease.Existing therapeutic approaches fail to alter disease prog... An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)R-mediated signaling,plays a role in the pathogenesis of Parkinson's disease.Existing therapeutic approaches fail to alter disease progression,demonstrating the need for novel approaches in PD.Repetitive transcranial magnetic stimulation is a non-invasive approach that has been shown to improve motor and non-motor symptoms of Parkinson's disease.However,the underlying mechanisms of the beneficial effects of repetitive transcranial magnetic stimulation remain unknown.The purpose of this study is to investigate the extent to which the beneficial effects of prolonged intermittent theta burst stimulation in the 6-hydroxydopamine model of experimental parkinsonism are based on modulation of adenosine-mediated signaling.Animals with unilateral 6-hydroxydopamine lesions underwent intermittent theta burst stimulation for 3 weeks and were tested for motor skills using the Rotarod test.Immunoblot,quantitative reverse transcription polymerase chain reaction,immunohistochemistry,and biochemical analysis of components of adenosine-mediated signaling were performed on the synaptosomal fraction of the lesioned caudate putamen.Prolonged intermittent theta burst stimulation improved motor symptoms in 6-hydroxydopamine-lesioned animals.A 6-hydroxydopamine lesion resulted in progressive loss of dopaminergic neurons in the caudate putamen.Treatment with intermittent theta burst stimulation began 7 days after the lesion,coinciding with the onset of motor symptoms.After treatment with prolonged intermittent theta burst stimulation,complete motor recovery was observed.This improvement was accompanied by downregulation of the e N/CD73-A_(2A)R pathway and a return to physiological levels of A_(1)R-adenosine deaminase 1 after 3 weeks of intermittent theta burst stimulation.Our results demonstrated that 6-hydroxydopamine-induced degeneration reduced the expression of A_(1)R and elevated the expression of A_(2A)R.Intermittent theta burst stimulation reversed these effects by restoring the abundances of A_(1)R and A_(2A)R to control levels.The shift in ARs expression likely restored the balance between dopamine-adenosine signaling,ultimately leading to the recovery of motor control. 展开更多
关键词 A_(1)R A_(2A)R adenosine receptors ADENOSINE ecto-5′-nucleotidase intermittent theta burst stimulation non-invasive brain stimulation Parkinson's disease purinergic signalling
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Molecular mechanism of pancreatic ductal adenocarcinoma:The heterogeneity of cancer-associated fibroblasts and key signaling pathways
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作者 Zhong-Yuan Hu Ding Ding +3 位作者 Yu Song Ya-Feng Deng Cheng-Ming Zhang Tao Yu 《World Journal of Clinical Oncology》 2025年第2期18-28,共11页
Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a d... Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a detailed exploration of epidemiological trends in pancreatic cancer and key molecular drivers,such as mutations in CDKN2A,KRAS,SMAD4,and TP53,along with the influence of cancer-associated fibroblasts(CAFs)on disease progression.In particular,we focused on the pivotal roles of signaling pathways such as the transforming growth factor-βand Wnt/β-catenin pathways in the development of pancreatic cancer and investigated their application in emerging therapeutic strategies.This study provides new scientific perspectives on pancreatic cancer treatment,especially in the development of precision medicine and targeted therapeutic strategies,and demonstrates the importance of signaling pathway research in the development of effective therapeutic regimens.Future studies should explore the subtypes of CAFs and their specific roles in the tumor microenvironment to devise more effective therapeutic methods. 展开更多
关键词 Pancreatic cancer FIBROBLASTS signaling pathways Tumor microenvironment
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Overview of bile acid signaling in the cardiovascular system 被引量:6
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作者 Rou Zhang Wen-Qi Ma +6 位作者 Meng-Jun Fu Juan Li Chun-Hua Hu Yi Chen Mi-Mi Zhou Zhi-Jie Gao Ying-Li He 《World Journal of Clinical Cases》 SCIE 2021年第2期308-320,共13页
Bile acids(BAs)are classically known to play a vital role in the metabolism of lipids and in absorption.It is now well established that BAs act as signaling molecules,activating different receptors(such as farnesoid X... Bile acids(BAs)are classically known to play a vital role in the metabolism of lipids and in absorption.It is now well established that BAs act as signaling molecules,activating different receptors(such as farnesoid X receptor,vitamin D receptor,Takeda G-protein-coupled receptor 5,sphingosine-1-phosphate,muscarinic receptors,and big potassium channels)and participating in the regulation of energy homeostasis and lipid and glucose metabolism.In addition,increased BAs can impair cardiovascular function in liver cirrhosis.Approximately 50%of patients with cirrhosis develop cirrhotic cardiomyopathy.Exposure to high concentrations of hydrophobic BAs has been shown to be related to adverse effects with respect to vascular tension,endothelial function,arrhythmias,coronary atherosclerotic heart disease,and heart failure.The BAs in the serum BA pool have relevant through their hydrophobicity,and the lipophilic BAs are more harmful to the heart.Interestingly,ursodeoxycholic acid is a hydrophilic BA,and it is used as a therapeutic drug to reverse and protect the harmful cardiac effects caused by hydrophobic elevated BAs.In order to elucidate the mechanism of BAs and cardiovascular function,abundant experiments have been conducted in vitro and in vivo.The aim of this review was to explore the mechanism of BAs in the cardiovascular system. 展开更多
关键词 Bile acids CARDIOVASCULAR ARTERIES RECEPTORS signaling CIRRHOSIS
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Roles of Eph/ephrin bidirectional signaling during injury and recovery of the central nervous system 被引量:4
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作者 Yue Wan Jin-Shan Yang +3 位作者 Li-Cai Xu Xiao-Jiang Huang Wei Wang Min-Jie Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1313-1321,共9页
Multiple cellular components, including neuronal, glial and endothelial ceils, are involved in the sophis- ticated pathological processes following central nervous system injury. The pathological process cannot reduce... Multiple cellular components, including neuronal, glial and endothelial ceils, are involved in the sophis- ticated pathological processes following central nervous system injury. The pathological process cannot reduce damage or improve functional recovery by merely targeting the molecular mechanisms of neuronal cell death after central nerve system injuries. Eph receptors and ephrin ligands have drawn wide attention since the discovery of their extensive distribution and unique bidirectional signaling between astrocytes and neurons. The roles of Eph/ephrin bidirectional signaling in the developmental processes have been re- ported in previous research. Recent observations suggest that Eph/ephrin bidirectional signaling continues to be expressed in most regions and cell types in the adult central nervous system, playing diverse roles. The Eph/ephrin complex mediates neurogenesis and angiogenesis, promotes glial scar formation, regulates endocrine levels, inhibits myelin formation and aggravates inflammation and nerve pain caused by injury. ~lhe interaction between Eph and ephrin is also considered to be the key to angiogenesis. This review focus- es on the roles of Eph/ephrin bidirectional signaling in the repair of central nervous system injuries. 展开更多
关键词 nerve regeneration Eph/ephrin bidirectional signaling central nervous system INJURY RECOVERY NEURONS glial cells
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BER Performance of FSO Communication System with Differential Signaling over Correlated Atmospheric Turbulence Fading 被引量:3
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作者 Xiaoyan Li Xiaohui Zhao +1 位作者 Peng Zhang Shoufeng Tong 《China Communications》 SCIE CSCD 2020年第4期51-65,共15页
Free space optical(FSO) communication system with differential signaling possesses the advantage of requiring no channel state information and avoiding computational load or link throughput reduction compared to the s... Free space optical(FSO) communication system with differential signaling possesses the advantage of requiring no channel state information and avoiding computational load or link throughput reduction compared to the systems with conventional receivers. In this work, we investigate bit error rate(BER) performance of this system over partially and fully correlated atmospheric turbulence fading. In order to conduct the above analysis, we obtain a probability density functions(PDF) of the channel fading on the differential signals and derive our instantaneous BER using differential signaling scheme. Based on these results, we develop two closed-form mathematical expressions for the average BER under fully correlated and partially correlated fading in the convergent infinite series confirmed by Cauchy’s ratio test. The accuracy of the derived BER expressions is demonstrated by the Monte Carlo simulations, and the analyses for the effects of the system parameters on the BER performance are provided. 展开更多
关键词 free space optical communication BER performance CORRELATED atmospheric TURBULENCE FADING differential signaling
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Purinergic signaling systems across comparative models of spinal cord injury 被引量:1
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作者 Eva E.Stefanova Angela L.Scott 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第11期2391-2398,共8页
Within the last several decades,the scientific community has made substantial progress in elucidating the complex pathophysiology underlying spinal cord injury.However,despite the many advances using conventional mamm... Within the last several decades,the scientific community has made substantial progress in elucidating the complex pathophysiology underlying spinal cord injury.However,despite the many advances using conventional mammalian models,both cellular and axonal regeneration following spinal cord injury have remained out of reach.In this sense,turning to non-mammalian,regenerative species presents a unique opportunity to identify pro-regenerative cues and chara cterize a spinal cord microenvironment permissive to re-growth.Among the signaling pathways hypothesized to be dysregulated during spinal cord injury is the purinergic signaling system.In addition to its well-known role as energy currency in cells,ATP and its metabolites are small molecule neurotransmitte rs that mediate many diverse cellular processes within the central nervous system.While our unde rstanding of the roles of the purinergic system following spinal cord injury is limited,this signaling pathway has been implicated in all injury-induced secondary processes,including cellular death,inflammation,reactive gliosis,and neural regeneration.Given that the purinergic system is also evolutionarily conserved between mammalian and non-mammalian species,comparisons of these roles may provide important insights into conditions responsible for recovery success.Here,we compare the secondary processes between key model species and the influence of purinergic signaling in each context.As our understanding of this signaling system and pro-regenerative conditions continues to evolve,so does the potential for the development of novel therapeutic interventions for spinal cord injury. 展开更多
关键词 cell death differenriation GLIA inflammation NEUROGENESIS PROLIFERATION purinergic signaling reactive gliosis regeneration spinal cord injury TELEOST
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Promoting axon regeneration in the central nervous system by increasing PI3-kinase signaling 被引量:1
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作者 Bart Nieuwenhuis Richard Eva 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第6期1172-1182,共11页
Much research has focused on the PI3-kinase and PTEN signaling pathway with the aim to stimulate repair of the injured central nervous system.Axons in the central nervous system fail to regenerate,meaning that injurie... Much research has focused on the PI3-kinase and PTEN signaling pathway with the aim to stimulate repair of the injured central nervous system.Axons in the central nervous system fail to regenerate,meaning that injuries or diseases that cause loss of axonal connectivity have life-changing consequences.In 2008,genetic deletion of PTEN was identified as a means of stimulating robust regeneration in the optic nerve.PTEN is a phosphatase that opposes the actions of PI3-kinase,a family of enzymes that function to generate the membrane phospholipid PIP_(3) from PIP_(2)(phosphatidylinositol(3,4,5)-trisphosphate from phosphatidylinositol(4,5)-bisphosphate).Deletion of PTEN therefore allows elevated signaling downstream of PI3-kinase,and was initially demonstrated to promote axon regeneration by signaling through mTOR.More recently,additional mechanisms have been identified that contribute to the neuron-intrinsic control of regenerative ability.This review describes neuronal signaling pathways downstream of PI3-kinase and PIP3,and considers them in relation to both developmental and regenerative axon growth.We briefly discuss the key neuron-intrinsic mechanisms that govern regenerative ability,and describe how these are affected by signaling through PI3-kinase.We highlight the recent finding of a developmental decline in the generation of PIP_(3) as a key reason for regenerative failure,and summarize the studies that target an increase in signaling downstream of PI3-kinase to facilitate regeneration in the adult central nervous system.Finally,we discuss obstacles that remain to be overcome in order to generate a robust strategy for repairing the injured central nervous system through manipulation of PI3-kinase signaling. 展开更多
关键词 axon cytoskeleton axon regeneration axon transport cell signaling central nervous system growth cone NEUROPROTECTION PI3-kinase PI3K PTEN TRAFFICKING TRANSCRIPTION translation
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The neuroprotective and regenerative potential of parkin and GDNF/Ret signaling in the midbrain dopaminergic system 被引量:2
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作者 Edgar R.Kramer 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第11期1752-1753,共2页
Parkinson's disease(PD)is the second most common neurodegenerative disease after Alzheimer's disease.The etiology of PD is still not completely understood,but the degeneration of dopaminergic(DA)neurons in the s... Parkinson's disease(PD)is the second most common neurodegenerative disease after Alzheimer's disease.The etiology of PD is still not completely understood,but the degeneration of dopaminergic(DA)neurons in the substantia nigra pars compacta(SNpc),loss of DA innervation of the striatum,and protein aggregates in the form of Lewy bodies and neurites are its established hallmarks. In addition to α-synuclein accumu- lation in Lewy bodies and neurites, genetic mutations in the genes encoding parkin, PINK, DJ-1, LRRK2 and other proteins are associated with the inherited form of PD. An association study linked also the receptor tyrosine kinase Ret to PD (Meka et al., 2015). Currently there are only symptomatic treatments available for PD but no cure. Consequently much effort is being made to find neurotrophic and other factors able to stimulate SNpc DA neuron protection and regeneration. 展开更多
关键词 GDNF The neuroprotective and regenerative potential of parkin and GDNF/Ret signaling in the midbrain dopaminergic system
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Neuropathy optic glaucomatosa induced by systemic hypertension through activation endothelin-1 signaling pathway in central retinal artery in rats 被引量:1
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作者 Seskoati Prayitnaningsih Hidayat Sujuti +5 位作者 Maksum Effendi Aulia Abdullah Nanda Wahyu Anandita Febriani Yohana Nur Permatasari Mohamad Aris Widodo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第11期1568-1577,共10页
AIM: To evaluate effect of hypertension on retinal ganglion cell(RGC) apoptosis, intraocular pressure(IOP),and the activation of endothelin-1(ET-1) signaling pathway in central retinal artery(CRA) in rats.MET... AIM: To evaluate effect of hypertension on retinal ganglion cell(RGC) apoptosis, intraocular pressure(IOP),and the activation of endothelin-1(ET-1) signaling pathway in central retinal artery(CRA) in rats.METHODS: The experimental study was performed on20 male Sprague Dawley rats that were divided into control group, and hypertension groups. The hypertension was induced by subcutaneous deoxycorticoacetate(DOCA)10 mg/kg twice a week and administered 0.9% Na Cl solution daily for 2, 6, and 10 wk. Blood pressure(BP) was measured using animal BP analyzer. IOP was measured by handheld tonometry. Retinal tissue preparations by paraffin blocks were made after enucleation. The expression of ET-1, e NOS, ET-1 receptor A(ETRA), ET-1receptor B(ETRB), and phosphorylated myosin light chain kinase(MLCK), and caldesmon(Ca D) in CRA and RGC apoptosis were evaluated through immunofluorescent staining method then observed using laser scanning confocal microscopy. RESULTS: BP significantly increased in all of the hypertension groups compared to control(P =0.001).Peak IOP elevation(7.78±4.14 mm Hg) and RGC apoptosis(576.15±33.28 Au) occurred on 2wk of hypertension. ET-1expression(1238.6±55.1 Au) and e NOS expression(2814.2±70.7 Au) were found highest in 2wk of hypertension,although the ratio of ET-1/e NOS decreased since 2wk.ETRAreached peak expression in 10 wk of hypertension(1219.4 ±6.3 Au), while ETRBsignificantly increased only in 2 weeks group(1069.2 ±9.6 Au). The highest MLCK expression(1190.09±58.32 Au), Ca D(1670.28±18.36 Au)were also found in 2wk of hypertension.CONCLUSION: Hypertension effects to activation of ET-1 signaling pathway significantly in CRA, elevation of IOP, and RGC apoptosis. The highest value was achieved at 2wk, which is the development phase of hypertension. 展开更多
关键词 hypertension central retinal artery endothelin- 1 signaling pathway RATS
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Gut microbiota dysbiosis contributes toα-synuclein-related pathology associated with C/EBPβ/AEP signaling activation in a mouse model of Parkinson’s disease 被引量:4
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作者 Xiaoli Fang Sha Liu +9 位作者 Bilal Muhammad Mingxuan Zheng Xing Ge Yan Xu Shu Kan Yang Zhang Yinghua Yu Kuiyang Zheng Deqin Geng Chun-Feng Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2081-2088,共8页
Parkinson’s disease is a neurodegenerative disease characterized by motor and gastrointestinal dysfunction.Gastrointestinal dysfunction can precede the onset of motor symptoms by several years.Gut microbiota dysbiosi... Parkinson’s disease is a neurodegenerative disease characterized by motor and gastrointestinal dysfunction.Gastrointestinal dysfunction can precede the onset of motor symptoms by several years.Gut microbiota dysbiosis is involved in the pathogenesis of Parkinson’s disease,whether it plays a causal role in motor dysfunction,and the mechanism underlying this potential effect,remain unknown.CCAAT/enhancer binding proteinβ/asparagine endopeptidase(C/EBPβ/AEP)signaling,activated by bacterial endotoxin,can promoteα-synuclein transcription,thereby contributing to Parkinson’s disease pathology.In this study,we aimed to investigate the role of the gut microbiota in C/EBPβ/AEP signaling,α-synuclein-related pathology,and motor symptoms using a rotenone-induced mouse model of Parkinson’s disease combined with antibiotic-induced microbiome depletion and fecal microbiota transplantation.We found that rotenone administration resulted in gut microbiota dysbiosis and perturbation of the intestinal barrier,as well as activation of the C/EBP/AEP pathway,α-synuclein aggregation,and tyrosine hydroxylase-positive neuron loss in the substantia nigra in mice with motor deficits.However,treatment with rotenone did not have any of these adverse effects in mice whose gut microbiota was depleted by pretreatment with antibiotics.Importantly,we found that transplanting gut microbiota derived from mice treated with rotenone induced motor deficits,intestinal inflammation,and endotoxemia.Transplantation of fecal microbiota from healthy control mice alleviated rotenone-induced motor deficits,intestinal inflammation,endotoxemia,and intestinal barrier impairment.These results highlight the vital role that gut microbiota dysbiosis plays in inducing motor deficits,C/EBPβ/AEP signaling activation,andα-synuclein-related pathology in a rotenone-induced mouse model of Parkinson’s disease.Additionally,our findings suggest that supplementing with healthy microbiota may be a safe and effective treatment that could help ameliorate the progression of motor deficits in patients with Parkinson’s disease. 展开更多
关键词 C/EBP/AEP signaling pathway ENDOTOXEMIA fecal microbiota transplantation intestinal barrier intestinal inflammation microbiota-gut-brain axis Parkinson’s disease
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Melatonin improves synapse development by PI3K/Akt signaling in a mouse model of autism spectrum disorder 被引量:4
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作者 Luyi Wang Man Xu +8 位作者 Yan Wang Feifei Wang Jing Deng Xiaoya Wang Yu Zhao Ailing Liao Feng Yang Shali Wang Yingbo Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1618-1624,共7页
Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes,including Ctnnd2 as a candidate gene.Ctnnd2knockout mice,serving as an animal model of autis m,have been demonstrate... Autism spectrum disorders are a group of neurodevelopmental disorders involving more than 1100 genes,including Ctnnd2 as a candidate gene.Ctnnd2knockout mice,serving as an animal model of autis m,have been demonstrated to exhibit decreased density of dendritic spines.The role of melatonin,as a neuro hormone capable of effectively alleviating social interaction deficits and regulating the development of dendritic spines,in Ctnnd2 deletion-induced nerve injury remains unclea r.In the present study,we discove red that the deletion of exon 2 of the Ctnnd2 gene was linked to social interaction deficits,spine loss,impaired inhibitory neurons,and suppressed phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt) signal pathway in the prefrontal cortex.Our findings demonstrated that the long-term oral administration of melatonin for 28 days effectively alleviated the aforementioned abnormalities in Ctnnd2 gene-knockout mice.Furthermore,the administration of melatonin in the prefro ntal cortex was found to improve synaptic function and activate the PI3K/Akt signal pathway in this region.The pharmacological blockade of the PI3K/Akt signal pathway with a PI3K/Akt inhibitor,wo rtmannin,and melatonin receptor antagonists,luzindole and 4-phenyl-2-propionamidotetralin,prevented the melatonin-induced enhancement of GABAergic synaptic function.These findings suggest that melatonin treatment can ameliorate GABAe rgic synaptic function by activating the PI3K/Akt signal pathway,which may contribute to the improvement of dendritic spine abnormalities in autism spectrum disorders. 展开更多
关键词 AUTISM Ctnnd2 deletion GABAergic neurons MELATONIN PI3K/Akt signal pathway prefrontal cortex social behavior spine density synaptic-associated proteins
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Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway 被引量:2
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作者 Chenxi Zhao Tiangang Zhou +9 位作者 Ming Li Jie Liu Xiaoqing Zhao Yilin Pang Xinjie Liu Jiawei Zhang Lei Ma Wenxiang Li Xue Yao Shiqing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期434-439,共6页
Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we... Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we established a rat model of T10 moderate spinal cord injury using an NYU Impactor ModerⅢand performed intraperitoneal injection of argatroban for 3 consecutive days.Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord.RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway,which is involved in astrogliosis and glial scar formation.Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway.Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord.Taken together,these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway,thereby promoting the recovery of neurological function after spinal cord injury. 展开更多
关键词 ARGATROBAN ASTROGLIOSIS JAK/STAT signaling pathway protease-activated receptor-1 spinal cord injury THROMBIN vimentin
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Spi1 regulates the microglial/macrophage inflammatory response via the PI3K/AKT/mTOR signaling pathway after intracerebral hemorrhage 被引量:2
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作者 Guoqiang Zhang Jianan Lu +7 位作者 Jingwei Zheng Shuhao Mei Huaming Li Xiaotao Zhang An Ping Shiqi Gao Yuanjian Fang Jun Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期161-170,共10页
Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related t... Preclinical and clinical studies have shown that microglia and macrophages participate in a multiphasic brain damage repair process following intracerebral hemorrhage.The E26 transformation-specific sequence-related transcription factor Spi1 regulates microglial/macrophage commitment and maturation.However,the effect of Spi1 on intracerebral hemorrhage remains unclear.In this study,we found that Spi1 may regulate recovery from the neuroinflammation and neurofunctional damage caused by intracerebral hemorrhage by modulating the microglial/macrophage transcriptome.We showed that high Spi1expression in microglia/macrophages after intracerebral hemorrhage is associated with the activation of many pathways that promote phagocytosis,glycolysis,and autophagy,as well as debris clearance and sustained remyelination.Notably,microglia with higher levels of Soil expression were chara cterized by activation of pathways associated with a variety of hemorrhage-related cellular processes,such as complement activation,angiogenesis,and coagulation.In conclusion,our results suggest that Spi1 plays a vital role in the microglial/macrophage inflammatory response following intracerebral hemorrhage.This new insight into the regulation of Spi1 and its target genes may advance our understanding of neuroinflammation in intracerebral hemorrhage and provide therapeutic targets for patients with intracerebral hemorrhage. 展开更多
关键词 intracerebral hemorrhage MACROPHAGE microglia neuroinflammation PHAGOCYTOSIS PI3K/AKT/mTOR signaling pathway Spi1 TRANSCRIPTOMICS
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