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Journal of Materials Science & Technology 2002年第2期18卷 113-117页

作者： G.Dehm B.J.Inkson 等 Max-Planck-InstitutfirtMetallforschung Seestr9270174StuttgartGermany DepartmentofMaterials UniversityofOxfordParksRoadOxfordOX13PHU.K.

Stresses in epitaxial and textured Al films were determined by substrate-curvature measurements. It is found that in both cases the flow stresses increase with the decrease of film thickness. The flow stress in the epitaxial Al films is in agreement with a dislocation-based model, while the same model strongly underestimates the flow stress of textured Al films. In-situ transmission electron microscopy studies indicate that dislocations channeling through epitaxial Al films on single-crystalline (0001) α-Al2O3 substrates frequently deposit dislocation segments adjacent to the interface. Furthermore, the Al/α-Al2O3 interface can act as a dislocation source. In this case, the interface is between two crystalline lattices. In contrast, the interface of textured Al films on oxidized silicon substrates is between the crystalline Al and the amorphous SiOx interlayer. It is speculated that the different nature of the interfaces changes the dislocation mechanism and thus influences the flow stress.

关键词： Thin film plasticity Dislocation Interface

Neuroregeneration and plasticity: a review of the physiological mechanisms for achieving functional recovery postinjury

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Military Medical Research 2020年第4期7卷 464-481页

作者： Palaniappan Ganesh Nagappan Hong Chen De-Yun Wang School of Clinical Medicine University of CambridgeCambridge CB21TNUK Shengli Clinical College of Fujian Medical University Department of NeurologyFujian Provincial HospitalFuzhouFujian 350001China Department of Otolaryngology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 119228Singapore

Neuronal networks,especially those in the central nervous system(CNS),evolved to support extensive functional capabilities while ensuring stability.Several physiological"brakes"that maintain the stability of the neuronal networks in a healthy state quickly become a hinderance postinjury.These"brakes"include inhibition from the extracellular environment,intrinsic factors of neurons and the control of neuronal plasticity.There are distinct differences between the neuronal networks in the peripheral nervous system(PNS)and the CNS.Underpinning these differences is the trade-off between reduced functional capabilities with increased adaptability through the formation of new connections and new neurons.The PNS has"facilitators"that stimulate neuroregeneration and plasticity,while the CNS has"brakes"that limit them.By studying how these"facilitators"and"brakes"work and identifying the key processes and molecules involved,we can attempt to apply these theories to the neuronal networks of the CNS to increase its adaptability.The difference in adaptability between the CNS and PNS leads to a difference in neuroregenerative properties and plasticity.plasticity ensures quick functional recovery of abilities in the short and medium term.Neuroregeneration involves synthesizing new neurons and connections,providing extra resources in the long term to replace those damaged by the injury,and achieving a lasting functional recovery.Therefore,by understanding the factors that affect neuroregeneration and plasticity,we can combine their advantages and develop rehabilitation techniques.Rehabilitation training methods,coordinated with pharmacological interventions and/or electrical stimulation,contributes to a precise,holistic treatment plan that achieves functional recovery from nervous system injuries.Furthermore,these techniques are not limited to limb movement,as other functions lost as a result of brain injury,such as speech,can also be recovered with an appropriate training program.

关键词： Neuroregeneration plasticity Neuronal systems Postinjury Central nervous system Peripheral nervous system Rehabilitation

Cephalopod RNA recoding: linking protein plasticity to thermal adaptation and catalyzing beyond-species protein characterization

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5146-5148页

作者： Junyi Wang Guoping Li Min Wu Laboratory of Allergy and Precision Medicine Department of Pulmonary and Critical Care MedicineChengdu Institute of Respiratory HealthThe Third People’s Hospital of ChengduAffiliated Hospital of Southwest Jiaotong UniversityChengduChina State Key Laboratory of Quality Research in Chinese Medicine Macao University of Science and TechnologyTaipaMacao SARChina Wenzhou Institute University of Chinese Academy of Sciences325000WenzhouZhejiangChina

A recent publication in Cell by Rangan et al.highlights the remarkable ability of squids to dynamically regulate the function of microtubule motor proteins through RNA recoding in response to ocean temperature fluctuations(Fig.1).This study not only provides valuable insights into the crucial role of RNA recoding in generating protein plasticity for adapting to ever-changing environmental conditions but also presents an unprecedented methodology facilitating characterization of conserved non-cephalopod proteins,particularly in the realm of human health and disease.1 Fig.

关键词： plasticity characterization

plasticity Enhancement Processes in NiAl and MoSi_2

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Journal of Materials Science & Technology 1993年第6期9卷 405-415页

作者： R.Gibala H.Chang C.M.Czarnik K.M.Edwards A.Misra Department of Materials Science and Engineering,University of Michigan,Ann Arbor,Michigan 48109-2136,USA Univ of Michigan Ann Arbor United States

This paper demonstrates that plasticity enhancement processes previously observed in bcc metals and associated with the presence of surface films and precipitates or dispersoids are operative in or- dered intermetallic compounds.' Some specific results are given for NiAl-and MoSi_2-based materials.The plasticity of NiAl and related B2 ordered alloys at room temperature during monotonic deformation can be enhanced by application of surface films such as electroless nickel platings.Sig- nificant effects are also observed during cyclic deformation.The presence of ductile second phases such as fcc γ or the ordered phase γ' introduced by alloying also enhances the plasticity of NiAl. MoSi_2 exhibits similar effects of surface films and second phases,but primarily at elevated tempera- tures,T>900℃.In this paper,we illustrate the effects of ZrO_2 surface films deposited near room temperature and TiC particulate additions introduced by powder processing techniques.In all cases, the plasticity enhancement is associated with enhanced dislocation generation processes under the conditions of constrained deformation at the film-substrate or precipitate/dispersoid-matrix inter- face of the composite system.

关键词： plasticity ordered intermetallics NiAl MoSi_2

Curcumin improves synaptic plasticity impairment induced by HIV-1gp120 V3 loop

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Neural Regeneration Research 2015年第6期10卷 925-931页

作者： Ling-ling Shen Ming-liang Jiang Si-si Liu Min-chun Cai Zhong-qiu Hong Li-qing Lin Yan-yan Xing Gui-lin Chen Rui Pan Li-juan Yang Ying Xu Jun Dong Department of Pathophysiology Key Laboratory of the State Administration of Traditional Chinese MedicineMedical College of Jinan University GHM Institute of CNS Regeneration Jinan University Department of Orthopedics First Affiliated HospitalMedical College of Jinan University

Curcumin has been shown to significantly improve spatial memory impairment induced by HIV-1 gp 120 V3 in rats, but the electrophysiological mechanism remains unknown. Using extracellular microelectrode recording techniques, this study confirmed that the gp120 V3 loop could suppress long-term potentiation in the rat hippocampal CA1 region and synaptic plasticity, and that curcumin could antagonize these inhibitory effects. Using a Fura-2/AM calcium ion probe, we found that curcumin resisted the effects of the gp120 V3 loop on hippocampal synaptosomes and decreased Ca2＋ concentration in synaptosomes. This effect of curcumin was identical to nimodipine, suggesting that curcumin improved the inhibitory effects of gpl20 on synaptic plasticity, ameliorated damage caused to the central nervous system, and might be a potential neuroprotective drug.

关键词： nerve regeneration curcumin neurons HIV-1 gp l20 V3 loop plasticity HIV-associatedneurocognitive disorders output^input curve long-term potentiation excitatory postsynaptic potential paired-pulse facilitation Cd＋ synaptosome NSFC grants neural regeneration

AVP(4-8) Improves Cognitive Behaviors and Hippocampal Synaptic plasticity in the APP/PS1 Mouse Model of Alzheimer’s Disease

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Neuroscience Bulletin 2020年第3期36卷 254-262页

作者： Xiumin Zhang Fang Zhao Chenfang Wang Jun Zhang Yu Bai Fang Zhou Zhaojun Wang Meina Wu Wei Yang Junhong Guo Jinshun Qi Department of Neurology First HospitalShanxi Medical UniversityTaiyuan 030001China Department of Physiology Key laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuan 030001China

Memory deficits with aging are related to the neurodegeneration in the brain, including a reduction in arginine vasopressin(AVP) in the brain of patients with Alzheimer’s disease(AD). AVP(4-8), different from its precursor AVP, plays memory enhancement roles in the CNS without peripheral side-effects. However, it is not clear whether AVP(4-8) can improve cognitive behaviors and synaptic plasticity in the APP/PS1 mouse model of AD. Here, we investigated for the first time the neuroprotective effects of AVP(4-8) on memory behaviors and in vivo long-term potentiation(LTP) in APP/PS1-AD mice.The results showed that:(1) APP/PS1-AD mice had lower spontaneous alternation in the Y-maze than wild-type(WT) mice, and this was significantly reversed by AVP(4-8);(2) the prolonged escape latency of APP/PS1-AD mice in the Morris water maze was significantly decreased by AVP(4-8), and the decreased swimming time in target quadrant recovered significantly after AVP(4-8) treatment;(3) in vivo hippocampal LTP induced by high-frequency stimulation had a significant deficit in the AD mice, and this was partly rescued by AVP(4-8);(4) AVP(4-8)significantly up-regulated the expression levels of postsynaptic density 95(PSD95) and nerve growth factor(NGF)in the hippocampus of AD mice. These results reveal the beneficial effects of AVP(4-8) in APP/PS1-AD mice,showing that the intranasal administration of AVP(4-8)effectively improved the working memory and long-term spatial memory of APP/PS1-AD mice, which may be associated with the elevation of PSD95 and NGF levels in the brain and the maintenance of hippocampal synaptic plasticity.

关键词： AVP(4-8) APP/PS1 transgenic mice Cognitive behavior Synaptic plasticity In vivo hippocampal LTP

Targeting cancer cell plasticity by HDAC inhibition to reverse EBV-induced dedifferentiation in nasopharyngeal carcinoma

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Signal Transduction and Targeted Therapy 2021年第10期6卷 3045-3061页

作者： Jiajun Xie Zifeng Wang Wenjun Fan Youping Liu Fang Liu Xiangbo Wan Meiling Liu Xuan Wang Deshun Zeng Van Wang Bin He Min Yan Zijian Zhang Mengjuan Zhang Zhijie Hou Chunli Wang Zhijie Kang Wenfeng Fang Li Zhang Eric W-F Lam Xiang Guo Jinsong Yan Yixin Zeng Mingyuan Chen Quentin Liu Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangzhouChina Institute of Cancer Stem Cell Cancer CenterDalian Medical UniversityDalianChina Department of Hematology Liaoning Key Laboratory of Hematopoietic Stem Cell Transplantation and Translational MedicineLiaoning Medical Center for Hematopoietic Stem Cell TransplantationDalian Key Laboratory of HematologyDiamond Bay Institute of HematologyThe Affiliated Second Hospital of Dalian Medical UniversityDalianChina Department of Radiation Oncology The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Sun Yat-sen Institute of Hematology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina

Application of differentiation therapy targeting cellular plasticity for the treatment of solid malignancies has been lagging.Nasopharyngeal carci noma(NPC)is a distinctive cancer with poor differe ntiatio n and high prevalenee of Epstein-Barr virus(EBV)infection.Here,we show that the expressi on of EBV latent protein LMP1 in duces dediffere ntiated and stem-like status with high plasticity through the transcriptional inhibition of CEBPA.Mechanistically,LMP1 upregulates STAT5A and recruits HDAC 1/2 to the CEBPA locus to reduce its histone acetylation.HDAC inhibition restored CEBPA expression,reversing cellular dedifferentiation and stem-like status in mouse xeno graft models.These fin dings provide a novel mecha nistic epigenetic-based in sight into virus-induced cellular plasticity and propose a promising concept of differentiation therapy in solid tumor by using HDAC inhibitors to target cellular plasticity.

关键词： LMP1 cancer plasticity

An enriched environment promotes synaptic plasticity and cognitive recovery after permanent middle cerebral artery occlusion in mice

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Neural Regeneration Research 2019年第3期14卷 462-469页

作者： Chuan-Jie Wang Yi Wu Qun Zhang Ke-Wei Yu Yu-Yang Wang Department of Rehabilitation Medicine Huashan Hospital Fudan University

Cerebral ischemia activates an endogenous repair program that induces plastic changes in neurons. In this study, we investigated the effects of environmental enrichment on spatial learning and memory as well as on synaptic remodeling in a mouse model of chronic cerebral ischemia, produced by subjecting adult male C57 BL/6 mice to permanent left middle cerebral artery occlusion. Three days postoperatively, mice were randomly assigned to the environmental enrichment and standard housing groups. Mice in the standard housing group were housed and fed a standard diet. Mice in the environmental enrichment group were housed in a cage with various toys and fed a standard diet. Then, 28 days postoperatively, spatial learning and memory were tested using the Morris water maze. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 in the hippocampus were analyzed by western blot assay. The number of synapses was evaluated by electron microscopy. In the water maze test, mice in the environmental enrichment group had a shorter escape latency, traveled markedly longer distances, spent more time in the correct quadrant(northeast zone), and had a higher frequency of crossings compared with the standard housing group. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 were substantially upregulated in the hippocampus in the environmental enrichment group compared with the standard housing group. Furthermore, electron microscopy revealed that environmental enrichment increased the number of synapses in the hippocampal CA1 region. Collectively, these findings suggest that environmental enrichment ameliorates the spatial learning and memory impairment induced by permanent middle cerebral artery occlusion. Environmental enrichment in mice with cerebral ischemia likely promotes cognitive recovery by inducing plastic changes in synapses.

关键词： nerve regeneration environmental enrichment cerebral ischemia cognitive recovery brain plasticity and reorganization synaptic plasticity electron microscopy growth-associated protein 43 synaptophysin postsynaptic density protein 95 permanent middle cerebral artery occlusion neural regeneration

Hippo signaling and epithelial cell plasticity in mammalian liver development, homeostasis, injury and disease

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Science China(Life Sciences) 2019年第12期62卷 1609-1616页

作者： Randy L.Johnson Department of Cancer Biology University of Texas MD Anderson Cancer Center

A traditional view of cellular differentiation is unidirectional: progenitor cells adopt specific fates in response to environmental cues resulting in deployment of cell-specific gene expression programs and acquisition of unique differentiated cellular properties such as production of structural and functional proteins that define individual cell types. In both development and in tissue repair stem and progenitor cells are thought to both self-renew to maintain the pool of precursors and to expand to give rise to transient amplifying and differentiated cell types. Recently, however, it has become appreciated that differentiated cell types can be reprogrammed to adopt progenitor and stem cell properties. In the case of epithelial cells in the mammalian liver, hepatocytes and biliary epithelial cells there is a significant degree of plasticity between these lineages that has been implicated in mechanisms of tissue repair and in liver pathologies such as cancer. Recent studies have highlighted the role of Hippo signaling, an emerging growth control and tumor suppressor pathway, in regulating epithelial cell plasticity in the mammalian liver and in this review, the role of cellular plasticity and Hippo signaling in regulating normal and abnormal tissue responses in the mammalian liver will be discussed.

关键词： liver homeostasis plasticity regeneration cancer Hippo pathway

Pericyte plasticity in the Brain

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Neuroscience Bulletin 2019年第3期35卷 551-560页

作者： Gabryella S.P.Santos Luiz A.V.Magno Marco A.Romano-Silva Akiva Mintz Alexander Birbrair Departamento de Patologia Universidade Federal de Minas GeraisBelo HorizonteMG 31270-901Brazil Department of Mental Health Federal University of Minas GeraisBelo HorizonteMG 30130-100Brazil Department of Radiology Columbia University Medical CenterNew YorkNY 10032USA

Cerebral pericytes are perivascular cells that stabilize blood vessels. Little is known about the plasticity of pericytes in the adult brain in vivo. Recently, using stateof-the-art technologies, including two-photon microscopy in combination with sophisticated Cre/loxP in vivo tracing techniques, a novel role of pericytes was revealed in vascular remodeling in the adult brain. Strikingly, after pericyte ablation, neighboring pericytes expand their processes and prevent vascular dilatation. This new knowledge provides insights into pericyte plasticity in the adult brain.

关键词： Pericytes Brain Blood vessel plasticity