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Novel miRNA, miR-sc14, promotes Schwann cell proliferation and migration 被引量:8
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作者 Xi-Meng Ji Shan-Shan Wang +5 位作者 Xiao-Dong Cai Xing-Hui Wang Qian-Yan Liu Pan Wang Zhang-Chun Cheng Tian-Mei Qian 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第9期1651-1656,共6页
MicroRNAs refer to a class of endogenous,short non-coding RNAs that mediate numerous biological functions.MicroRNAs regulate various physiological and pathological activities of peripheral nerves,including peripheral ... MicroRNAs refer to a class of endogenous,short non-coding RNAs that mediate numerous biological functions.MicroRNAs regulate various physiological and pathological activities of peripheral nerves,including peripheral nerve repair and regeneration.Previously,using a rat sciatic nerve injury model,we identified many functionally annotated novel microRNAs,including miR-sc14.Here,we used real-time reverse transcription-polymerase chain reaction to examine miR-sc14 expression in rat sciatic nerve stumps.Our results show that miRsc14 is noticeably altered following sciatic nerve injury,being up-regulated at 1 day and diminished at 7 days.EdU and transwell chamber assay results showed that miR-sc14 mimic promoted proliferation and migration of Schwann cells,while miR-sc14 inhiThe study was approved by the Jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004).bitor suppressed their proliferation and migration.Additionally,bioinformatic analysis examined potential target genes of miR-sc14,and found that fibroblast growth factor receptor 2 might be a potential target gene.Specifically,our results show changes of miR-sc14 expression in the sciatic nerve of rats at different time points after nerve injury.Appropriately,up-regulation of miR-sc14 promoted proliferation and migration of Schwann cells.Consequently,miR-sc14 may be an intervention target to promote repair of peripheral nerve injury.The study was approved by the Jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004). 展开更多
关键词 NERVE REGENERATION novel microRNAs miR-sc14 PERIPHERAL NERVE injury cell PROLIFERATION cell migration Schwann cells fibroblast growth factor receptor 2 biological functions PERIPHERAL NERVE REGENERATION regulatory mechanisms neural REGENERATION
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Small extracellular vesicles derived from hair follicle neural crest stem cells enhance perineurial cell proliferation and migration via the TGF-β/SMAD/HAS2 pathway
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作者 Yiming Huo Bing Xiao +8 位作者 Haojie Yu Yang Xu Jiachen Zheng Chao Huang Ling Wang Haiyan Lin Jiajun Xu Pengfei Yang Fang Liu 《Neural Regeneration Research》 2026年第5期2060-2072,共13页
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi... Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects. 展开更多
关键词 hair follicle neural crest stem cells HAS2 migration miR-21-5p perineurial cells proliferation peripheral nerve injury SMAD7 small extracellular vesicles transforming growth factor-β/SMAD signaling pathway
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In-situ observations on interphase boundary migration and grain growth during α/γ phase transformation in iron-4.2%Cr alloy
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作者 渡边忠雄 OBARA Kouichi TSUREKAWA Sadahiro 《材料与冶金学报》 CAS 2005年第2期91-91,共1页
In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr allo... In-situ observations on α/γ phase transformation were made to study the effects of grain boundary microstructures on the formation of a new phase and the migration of α/γ interphase boundary in an iron4. 2%Cr alloy. It was found that triple junctions with more random boundaries could be the primary nucleation sites for a new phase, while triple junctions with low angle or low ∑ coincidence boundaries did not play any role as preferential sites. The migration of α/γ interphase boundary during heating over the transformation temperature range showed the two stage behaviour characterized by a stage with a migration velocity of 0. 33-0. 75 mm/s and secondly by a stage with 3. 7-7. 6 mm/s. It was also found that abnormal grain growth and a high density of ∑3 coincidence boundaries could occur in a phase with bcc structure after cycling of α/γ phase transformation. A new mechanism of nucleation and growth of a new phase in α/γ phase transformation is proposed on the basis of roles of plane-matching interphase boundaries, as previously discussed on the origin of anisotropy of grain growth due to the migration of {110} plane-matching boundaries in Fe-3z%Si alloy. The most recent theoretical work on the distribution of plane-matching boundaries in solids with different crystal structures was found to be useful for the understanding of nucleation and growth during α/γ phase transformation. 展开更多
关键词 In-situ phase velocity stage effects crystal with random origin the range after new was more play over high MOST for The to DID BCC It be
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Vertical dominant migration channel and hydrocarbon migration in complex fault zone, Bohai Bay sag, China 被引量:1
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作者 XU Changgui PENG Jingsong +2 位作者 WU Qingxun SUN Zhe YE Tao 《Petroleum Exploration and Development》 2019年第4期720-728,共9页
The quantitatively/semi-quantitatively formation conditions of vertical dominant hydrocarbon migration pathways were analyzed based on the big data analysis of petroleum geological parameters of complex fault Zone zon... The quantitatively/semi-quantitatively formation conditions of vertical dominant hydrocarbon migration pathways were analyzed based on the big data analysis of petroleum geological parameters of complex fault Zone zone in the central-south Bohai Bay. According to this condition, the vertical dominant migration pathway and its charge points/segments are searched through structural modeling assistant analysis in the East Sag of Huanghekou. Under the constraints of charge points/segments, numerical simulation of hydrocarbon charge and migration is carried out to successfully predict hydrocarbon migration pathways and hydrocarbon enrichment blocks in shallow layers of complex fault zone. The main results are as follows:(1) The hydrocarbon charge in shallow layers of the active fault zone is differential, the charge points/sections of vertical dominant migration pathways are the starting points of shallow hydrocarbon migration and are very important for the hydrocarbon migration and accumulation in the shallow layers.(2) Among the shallow faults, those cutting the deep transfer bins or deep major migration pathways, with fault throw of more than 80 m in the accumulation period and the juxtaposition thickness between fault and caprock of the deep layers of less than 400 m are likely to be vertical dominant migration pathways in the sag area.(3) By controlling the vertical dominant migration pathways and charging points/segments in carrier layer, Neo-tectonic movement caused the differential hydrocarbon accumulation in the complex fault zone. The research results are of great significance for the fine exploration of the complex fault zone. 展开更多
关键词 offshore Bohai Bay Basin SAG area VERTICAL DOMINANT migration pathway COMPLEX fault zone charge points NEOTECTONIC movement big data analysis
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Historical Course Follows Climate Change: Patterns of the Northern Hemisphere — From Peoples’ Migration until the Industrial Revolution (3<sup>rd</sup>-18<sup>th</sup>Century)
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 2018年第13期1167-1194,共28页
This paper relates to the statement that the so-called “Little Ice Age” (RCC 6: 1.350-1.800 A.D.) represents—besides the 8k-Event (8.200-8.000 yr cal. B.P.)—the fastest and strongest onset in Holocene History [1].... This paper relates to the statement that the so-called “Little Ice Age” (RCC 6: 1.350-1.800 A.D.) represents—besides the 8k-Event (8.200-8.000 yr cal. B.P.)—the fastest and strongest onset in Holocene History [1]. Its intention focuses on the correlation of interplaying natural processes (i.e. solar energy variation, aerosols, oceanic currents, volcanism as part of plate tectonics, heat flow) with social/political evidence through the time-span of Peoples’ Migration until Industrial Revolution (3rd-18th Century). The time-span comprises the cool/wet/respectively dry climate phase of the P.M. (260-550), a Climate Optimum (600-1.100 A.D.) owning a final Thermal Maximum (1.100-1.260 A.D.) and the “little Ice Age” (1.350-1.800 A.D.), the latter intercalated by the Sp&#246;rer Minimum (1.460-1.550 A.D.) and the Maunder Minimum (1.650-1.720 A.D.). Thereby, an average temperature difference of 1.0&#176;C - 2.0&#176;C seems sufficient for incising climatic/cultural consequences [2]. It has become obvious that a Climate Optimum primarily provides constructive life conditions;however with a problematic final as the following “Effect-Chain” tells: balanced agricultural/cultural population growth → rich harvests → satisfying nourishment → health, encouragement → overpopulation under favorable materialistic conditions → increasing stress → lack of food, high prices → revolts → migration. In contrast, cool/wet/resp. dry conditions originate destructive/depressive conditions (see Peoples’ Migration) which initiate the following “Effect Chain”: bad agricultural conditions → poor/no harvesting → famine → disease, growing death rate → social, political revolts, wars → human cruelties with psychic/religious background (inquisition, witch-combustion → general chaos (30 yr-war) → death, migration (maritime endeavors, colonization). Furthermore, it should be stressed that volcanic aerosols play besides the solar influx variation—an important role on climate/cultural change [3]. However, the effects of oceanic currents’ heat flow of Mid-Oceanic Ridges and Hot Spots, as well as Earth-Magnetism and Sun/Earth Geometry are poorly understood in this context (Example: Iceland as hot spot situated on the Mid-Atlantic Ridge having been working since 40 Ma). The Chapter-introducing citations play a challenging role in regard to Science Criticism and touch the so-called 95% Confidence line (accepted realm of causal interrelation and according recommendation to Society [4]). 展开更多
关键词 Little Ice Age Climate-Change Social/Political Concern Psychic/Spiritual Implication VOLCANISM Plate Tectonics Peoples migration Northern HEMISPHERE Natural/Cultural Effect-Chains Science Criticism
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Retraction:MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells
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作者 Oncology Research Editorial Office 《Oncology Research》 2026年第1期621-621,共1页
The published article titled“MicroRNA-133b Inhibits Proliferation,Cellular Migration,and Invasion via Targeting LASP1 in Hepatocarcinoma Cells”has been retracted from Oncology Research,Vol.25,No.8,2017,pp.1269–1282.
关键词 lasp cellular migration PROLIFERATION INVASION hepatocarcinoma cells targeting lasp microrna b
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Cell type-dependent role of transforming growth factor-βsignaling on postnatal neural stem cell proliferation and migration
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作者 Kierra Ware Joshua Peter +1 位作者 Lucas McClain Yu Luo 《Neural Regeneration Research》 2026年第3期1151-1161,共11页
Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postn... Adult neurogenesis continuously produces new neurons critical for cognitive plasticity in adult rodents.While it is known transforming growth factor-βsignaling is important in embryonic neurogenesis,its role in postnatal neurogenesis remains unclear.In this study,to define the precise role of transforming growth factor-βsignaling in postnatal neurogenesis at distinct stages of the neurogenic cascade both in vitro and in vivo,we developed two novel inducible and cell type-specific mouse models to specifically silence transforming growth factor-βsignaling in neural stem cells in(mGFAPcre-ALK5fl/fl-Ai9)or immature neuroblasts in(DCXcreERT2-ALK5fl/fl-Ai9).Our data showed that exogenous transforming growth factor-βtreatment led to inhibition of the proliferation of primary neural stem cells while stimulating their migration.These effects were abolished in activin-like kinase 5(ALK5)knockout primary neural stem cells.Consistent with this,inhibition of transforming growth factor-βsignaling with SB-431542 in wild-type neural stem cells stimulated proliferation while inhibited the migration of neural stem cells.Interestingly,deletion of transforming growth factor-βreceptor in neural stem cells in vivo inhibited the migration of postnatal born neurons in mGFAPcre-ALK5fl/fl-Ai9 mice,while abolishment of transforming growth factor-βsignaling in immature neuroblasts in DCXcreERT2-ALK5fl/fl-Ai9 mice did not affect the migration of these cells in the hippocampus.In summary,our data supports a dual role of transforming growth factor-βsignaling in the proliferation and migration of neural stem cells in vitro.Moreover,our data provides novel insights on cell type-specific-dependent requirements of transforming growth factor-βsignaling on neural stem cell proliferation and migration in vivo. 展开更多
关键词 adult neurogenesis DOUBLECORTIN HIPPOCAMPUS migration neural stem cells PROLIFERATION transforming growth factor-β
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Effect of particle size on migration and retention of bacteria in sand and its biomineralization
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作者 Hanjiang Lai Shuiquan Deng +5 位作者 Mingjuan Cui Shaohui Zheng Junjie Zheng Runming Liu Jianwei Zhang Yu Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1496-1503,共8页
Bacterial cells are widely accepted as nucleation sites for calcium carbonate precipitation in biomineralization based on the Microbially Induced Carbonate Precipitation(MICP)process.For MICP-based insitu biotreatment... Bacterial cells are widely accepted as nucleation sites for calcium carbonate precipitation in biomineralization based on the Microbially Induced Carbonate Precipitation(MICP)process.For MICP-based insitu biotreatment,the firstproblem to be solved is how to introduce and retain the bacterial cells in the soil,which involves the migration and retention of bacterial cells during the biogrouting process.Soil particle size,a key factor in determining pore throat size,can have a significanteffect on the migration and retention of bacterial cells in the soil and therefore on biomineralization.To investigate the effect of particle size on the migration and retention of bacterial cells in sand and its biomineralization,two sets of tests were carried out in this study,including percolation tests and sand column treatment tests.Soil urease activity(definedas urease activity per unit mass of soil)and calcium carbonate content of the biomineralized sand were measured to comprehensively assess the migration and retention of bacterial cells in the sand.The results indicate that sands with a particle size smaller than 0.25 mmwould inhibit the migration of bacteria in the sand,resulting in a nonuniform distribution of precipitated calcium carbonate and a low strength enhancement of biomineralization.On the other hand,sands with a particle size larger than 1.18 mm are unfavorable for retaining bacterial cells in the sand,resulting in low calcium conversion efficiency.Meanwhile,particle size would also affect the formation of effective calcium carbonate through interparticle contact number and interparticle pore size,and thus biomineralization. 展开更多
关键词 Microbially induced carbonate precipitation(MICP) Soil particle size Bacterial cell migration RETENTION BIOMINERALIZATION
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Redundant source-wavelet amplitude influence in wave-equation migration/demigration flow and its removal
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作者 QianCheng Liu JiaLe Kang Jie Li 《Earth and Planetary Physics》 2026年第1期75-81,共7页
In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly... In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly(effectively imposing a wavelet-spectrum weighting,often akin to an amplitude-squared bias).This redundancy degrades structural fidelity and amplitude balance yet is frequently overlooked.We(i)formalize the mechanism by which cross-correlation duplicates the source-wavelet amplitude effect in both migration and demigration,and(ii)introduce a source-equalized operator that removes the redundancy by deconvolving(or dividing by)the wavelet amplitude spectrum in the imaging condition and its demigration counterpart,while leaving phase/kinematics intact.Using a band-limited Ricker wavelet on a two-layer model and on Marmousi,we show that,if unmanaged,the redundant wavelet spectrum broadens main lobes,introduces ringing,and suppresses vertical resolution in migrated images,and inflates spectrum mismatches between demigrated and observed data even when peak times agree.With our correction,images recover observed-data-consistent bandwidth and sharpened interfaces,and demigrated data also exhibit improved spectrum conformity and reduced amplitude misfit.The results clarify when source amplitudes matter,why cross-correlation makes them redundantly matter,and how a lightweight spectral correction restores physically meaningful amplitude behavior in wave-equation migration/demigration. 展开更多
关键词 wave-equation migration DEmigration cross-correlation imaging condition source wavelet amplitude spectrum spectral deconvolution
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Origin and migration model of natural gas in L gas field, eastern slope of Yinggehai Sag, China 被引量:2
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作者 YANG Jihai HUANG Baojia 《Petroleum Exploration and Development》 2019年第3期471-481,共11页
Based on the chemical and stable carbon isotopic composition of natural gas and light hydrocarbons, along with regional geological data, the genetic type, origin and migration of natural gases in the L lithologic gas ... Based on the chemical and stable carbon isotopic composition of natural gas and light hydrocarbons, along with regional geological data, the genetic type, origin and migration of natural gases in the L lithologic gas field, the eastern slope of Yinggehai Sag were investigated. The results show that these gases have a considerable variation in chemical composition, with 33.6%–91.5% hydrocarbon, 0.5%-62.2% CO2, and dryness coefficients ranging from 0.94 to 0.99. The alkane gases are characterized by δ13C1 values of -40.71‰--27.40‰,δ13C2 values of –27.27‰– –20.26‰, and the isoparaffin contents accounting for 55%–73% of the total C5–C7 light hydrocarbons. These data indicate that the natural gases belong to the coal-type gas and are mainly derived from the Miocene terrigenous organic-rich source rocks. When the CO2 contents are greater than 10%, the δ13CCO2 values are –9.04‰ to – 0.95‰ and the associated helium has a 3He/4He value of 7.78×10^–8, suggesting that the CO2 here is crustal origin and inorganic and mainly sourced from the thermal decomposition of calcareous mudstone and carbonate in deep strata. The gas migrated in three ways, i.e., migration of gas from the Miocene source rock to the reservoirs nearby;vertical migration of highly mature gas from deeper Meishan and Sanya Formations source rock through concealed faults;and lateral migration along permeable sandbodies. The relatively large pressure difference between the “source” and “reservoir” is the key driving force for the vertical and lateral migration of gas. Short-distance migration and effective “source - reservoir” match control the gas distribution. 展开更多
关键词 EASTERN SLOPE of Yinggehai SAG L lithologic GAS field coal-type GAS CRUSTAL inorganic CO2 gas-source correlation migration model
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Mesh model building and migration and accumulation simulation of 3D hydrocarbon carrier system
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作者 GUO Qiulin LIU Jifeng +6 位作者 CHEN Ningsheng WU Xiaozhi REN Hongjia WEI Yanzhao CHEN Gang GONG Deyu YUAN Xuanjun 《Petroleum Exploration and Development》 2018年第6期1009-1022,共14页
Migration and accumulation simulation of oil and gas in carrier systems has always been a difficult subject in the quantitative study of petroleum geology. In view of the fact that the traditional geological modeling ... Migration and accumulation simulation of oil and gas in carrier systems has always been a difficult subject in the quantitative study of petroleum geology. In view of the fact that the traditional geological modeling technology can not establish the interrelation of carriers in three dimensional space, we have proposed a hybrid-dimensional mesh modeling technology consisting of body(stratum), surfaces(faults and unconformities), lines and points, which provides an important research method for the description of geometry of sand bodies, faults and unconformities, the 3 D geological modeling of complex tectonic areas, and the simulation of hydrocarbon migration and accumulation. Furthermore, we have advanced a 3 D hydrocarbon migration pathway tracking method based on the hybrid-dimensional mesh of the carrier system. The application of this technology in western Luliang Uplift of Junggar Basin shows that the technology can effectively characterize the transport effect of fault planes, unconformities and sand bodies, indicate the hydrocarbon migration pathways, simulate the process of oil accumulation, reservoir adjustment and secondary reservoir formation, predict the hydrocarbon distribution. It is found through the simulation that the areas around the paleo-oil reservoir and covered by migration pathways are favorable sites for oil and gas distribution. 展开更多
关键词 oil and gas migration and accumulation CARRIER SYSTEM hybrid-dimensional MESH migration pathway geological modeling MESH generation JUNGGAR Basin western Luliang UPLIFT
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Increased levels of miR-3099 induced by peripheral nerve injury promote Schwann cell proliferation and migration 被引量:7
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作者 Qian-Yan Liu Yang Miao +3 位作者 Xing-Hui Wang Pan Wang Zhang-Chun Cheng Tian-Mei Qian 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第3期525-531,共7页
MicroRNAs(miRNAs) can regulate the modulation of the phenotype of Schwann cells. Numerous novel miRNAs have been discovered and identified in rat sciatic nerve segments, including miR-3099. In the current study, miR-3... MicroRNAs(miRNAs) can regulate the modulation of the phenotype of Schwann cells. Numerous novel miRNAs have been discovered and identified in rat sciatic nerve segments, including miR-3099. In the current study, miR-3099 expression levels following peripheral nerve injury were measured in the proximal stumps of rat sciatic nerves after surgical crush. Real-time reverse transcription-polymerase chain reaction was used to determine miR-3099 expression in the crushed nerve segment at 0, 1, 4, 7, and 14 days post sciatic nerve injury, which was consistent with Solexa sequencing outcomes. Expression of miR-3099 was up-regulated following peripheral nerve injury. EdU and transwell chamber assays were used to observe the effect of miR-3099 on Schwann cell proliferation and migration. The results showed that increased miR-3099 expression promoted the proliferation and migration of Schwann cells. However, reduced miR-3099 expression suppressed the proliferation and migration of Schwann cells. The potential target genes of miR-3099 were also investigated by bioinformatic tools and high-throughput outcomes. miR-3099 targets genes Aqp4, St8 sia2, Tnfsf15, and Zbtb16 and affects the proliferation and migration of Schwann cells. This study examined the levels of miR-3099 at different time points following peripheral nerve injury. Our results confirmed that increased miR-3099 level induced by peripheral nerve injury can promote the proliferation and migration of Schwann cells. 展开更多
关键词 NERVE REGENERATION peripheral NERVE injury miR-3099 SCIATIC NERVE gene expression Schwann cells PROLIFERATION migration target genes mechanisms neural REGENERATION
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Photoperiod and Nitrogen Supply Limit the Scope of Northward Migration and Seed Transfer of Black Spruce in a Future Climate Associated with Doubled Atmospheric CO2 Concentration
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作者 Junlin Li Qing-Lai Dang Rongzhou Man 《American Journal of Plant Sciences》 2015年第1期189-200,共12页
The predicated changes in precipitation and temperature associated with the continued elevation of atmospheric CO2 concentration will trigger the northward shift of the Climate Envelopes for 130 North America tree spe... The predicated changes in precipitation and temperature associated with the continued elevation of atmospheric CO2 concentration will trigger the northward shift of the Climate Envelopes for 130 North America tree species by as much as 10 degrees. However, climate envelope models do not take into account changes in other factors that may also influence the survival and growth of plants at the predicted new locations, such as photoperiod and nutrient regimes. This study investigated how photoperiod and nitrogen supply would affect the ecophysiological traits of black spruce (Picea mariana (Mill) B. S. P.) that are critical for survival and growth at new locations predicted by climate envelope models. We exposed black spruce seedlings to the photoperiod regime at the seed origin (PS) and that 10° north of the seed origin (PNM) as predicted by climate envelope models under the current and doubled atmospheric CO2 concentration and different levels of N supply (30 vs. 300 μmol·mol-1 N). We found that the PNM and the 30 μmol·mol-1 N supply both had negative impact on the development of seedling cold hardiness in the fall, and led to earlier burst of the terminal bud and greater rate of mortality in the following growing season. While the PNM stimulated seedling growth in the first growing season, the effect was not sustained in the second growing season. Our results suggest that the photoperiod regimes and poor nutrient conditions at higher latitudes will likely constrain the scope of the northward migration or seed transfer of black spruce. 展开更多
关键词 Plant migration Tree Seed Transfer Nutrient Cold HARDINESS PICEA MARIANA (Mill) B.S.P. Boreal Forest Climate Envelope
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DLG3 Promotes Breast Cancer Cell Proliferation and Migration by Mediating STAT3 Activation
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作者 Khalid Idris GIDADO Rabiu LAWAN +4 位作者 PENG Xixia ZHANG Ziyang WAN Xiaochun LU Zhen ZHANG Guizhong 《集成技术》 2026年第1期41-55,共15页
Breast cancer(BRCA)is characterized by high heterogeneity,with aggressive subtypes frequently showing poor prognosis and resistance to conventional therapies,making the discovery of new therapeutic targets and strateg... Breast cancer(BRCA)is characterized by high heterogeneity,with aggressive subtypes frequently showing poor prognosis and resistance to conventional therapies,making the discovery of new therapeutic targets and strategies imperative.Although elevated expression of discs large homolog 3(DLG3)has been reported in BRCA,its functional role in disease progression remains unclear.We performed bioinformatic analyses of clinical datasets to evaluate the prognostic significance of DLG3 expression in BRCA patients.In vitro gain-and loss-of-function experiments were conducted to assess the impact of DLG3 on BRCA cell proliferation,migration,and colony formation.Transcriptomic profiling,coupled with pharmacological inhibition,was employed to identify and validate downstream signaling pathways.Additionally,we extended our validation to an in vivo model to assess the role of DLG3 in tumor progression.We found that elevated DLG3 levels correlated with poor prognosis in breast cancer patients.Functionally,DLG3 overexpression significantly promoted cell proliferation and migration in estrogen receptor-positive MCF7 and triple-negative MDA-MB-231 breast cancer cells,whereas its knockdown suppressed these effects.Transcriptomic analyses revealed that DLG3 activates signal transducer and activator of transcription 3(STAT3)signaling,a finding further corroborated by Western blot.Critically,treatment with the STAT3 inhibitor Stattic attenuated DLG3-driven proliferation and migration,supporting a DLG3-STAT3 oncogenic axis.Furthermore,in vivo studies validated the role of DLG3 in promoting tumor growth and its correlation with elevated STAT3 signaling,consistent with our in vitro findings.Our findings establish DLG3 as a novel driver of breast cancer progression that directly activates STAT3 signaling.DLG3 thus represents both a potential prognostic biomarker and a promising therapeutic target for aggressive breast cancer subtypes,including triple-negative breast cancer. 展开更多
关键词 breast cancer DLG3 STAT3 PROLIFERATION migration
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Oxime ester as bifunctional reagent for the alkylamination of alkynes via C-centered radical addition and N-centered radical migration
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作者 Keyuan Zhang Min Wang +3 位作者 Qi Jiang Bowu Dong Xin-Hua Duan Le Liu 《Science China Chemistry》 2026年第2期858-862,共5页
The radical addition/functional group migration strategy has emerged as a powerful tool for the difunctionalization of unsaturated hydrocarbons,yet the heteroatom-mediated functional group migration remains largely un... The radical addition/functional group migration strategy has emerged as a powerful tool for the difunctionalization of unsaturated hydrocarbons,yet the heteroatom-mediated functional group migration remains largely unexplored.Herein,we report an unprecedented radical difunctionalization of alkynes employing oxime esters as bifunctional reagents through a novel C-centered radical addition/N-centered radical translocation sequence.This innovative transformation paradigm enables efficient alkylamination of alkynes under mild photocatalytic redox conditions.Mechanistic investigations reveal a cascade sequence initiated by single-electron transfer from oxime derivatives,proceeding through radical addition,6-exo-trig cyclization,and subsequent imino group migration. 展开更多
关键词 bifunctional reagent alkylamination N-centered radical migration PHOTOREDOX tetrasubstituted alkenes
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Development of a model to simulate soil heavy metals lateral migration quantity based on SWAT in Huanjiang watershed,China 被引量:15
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作者 Pengwei Qiao Mei Lei +4 位作者 Sucai Yang Jun Yang Xiaoyong Zhou Nan Dong Guanghui Guo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第3期115-129,共15页
Lateral transportation of soil heavy metals in rainfall events could significantly increase the scope of pollution. Therefore, it is necessary to develop a model with high accuracy to simulate the migration quantity o... Lateral transportation of soil heavy metals in rainfall events could significantly increase the scope of pollution. Therefore, it is necessary to develop a model with high accuracy to simulate the migration quantity of heavy metals. A model for heavy metal migration simulation was developed based on the SWAT(Soil and Water Assessment Tool) model. This model took into consideration the influence of soil p H value, soil particle size, runoff volume, sediment amount,concentration of water-soluble heavy metals dissolved in runoff and insoluble absorbed to the soil particles. This model was reasonable in Huanjiang watershed, Guangxi Zhuang Autonomous Region, south China, covering an area of 273 km^2. The optimal drainage area threshold was determined by analyzing the effects of watershed subdivision on the simulation results to ensure the simulation accuracy. The main conclusions of this paper were:(1) watershed subdivision could affect simulation migration quantity of heavy metals;(2) the quantity of heavy metals transported by sediment accounted for 97%–99% of the total migration quantity in the study watershed. Therefore, sediment played the most important role in heavy metal migration;(3) the optimal drainage area threshold percentage to ensure high simulation accuracy was determined to be 2.01% of the total watershed;(4) with the optimal threshold percentage, this model could simulate the migration quantity of As, Pb and Cd accurately at the total watershed and subwatershed level. The results of this paper were useful for identifying the key regions with heavy metal migration. 展开更多
关键词 Soil heavy metal migration SIMULATION MODEL WATERSHED SUBDIVISION Optimal drainage area threshold PERCENTAGE SIMULATION accuracy
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Polysaccharide extracts of Astragalus membranaceus and Atractylodes macrocephala promote intestinal epithelial cell migration by activating the polyamine-mediated K^+ channel 被引量:16
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作者 ZENG Dan HU Can +6 位作者 LI Ru-Liu LIN Chuan-Quan CAI Jia-Zhong WU Ting-Ting SUI Jing-Jing LU Wen-Biao CHEN Wei-Wen 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2018年第9期674-682,共9页
Astragalus membranaceus(Radix Astragali, RA) and Atractylodes macrocephala(Rhizoma Atractylodis Macrocephalae, RAM) are often used to treat gastrointestinal diseases. In the present study, we determined the effects of... Astragalus membranaceus(Radix Astragali, RA) and Atractylodes macrocephala(Rhizoma Atractylodis Macrocephalae, RAM) are often used to treat gastrointestinal diseases. In the present study, we determined the effects of polysaccharides extracts from these two herbs on IEC-6 cell migration and explored the potential underlying mechanisms. A migration model with IEC-6 cells was induced using a single-edged razor blade along the diameter of cell layers in six-well polystyrene plates. The cells were grown in control--media or media containing spermidine(5 μmol·L^(-1), SPD), alpha-difluoromethylornithine(2.5 mmol·L^(-1), DFMO), 4-Aminopyridine-(40 μ-mol·L^(-1), 4-AP), the polysaccharide extracts of RA or RAM(50, 100, or 200 mg·L^(-1)), DFMO plus SPD, or DFMO plus polysaccharide extracts of RA or RAM for 12 or 24 h. Next, cytosolic free Ca^(2+)([Ca^(2+)]cyt) was measured using laser confocal microscopy, and cellular polyamine content was quantified with HPLC. Kv1.1 mRNA expression was assessed using RT-qPCR and Kv1.1 and RhoA protein expressions were measured with Western blotting analysis. A cell migration assay was carried out using Image-Pro Plus software. In addition, GC-MS was introduced to analyze the monosaccharide composition of both polysaccharide extracts. The resutls showed that treatment with polysaccharide extracts of RA or RAM significantly increased cellular polyamine content, elevated [Ca^(2+)]cyt and accelerated migration of IEC-6 cells, compared with the controls(P < 0.01). Polysaccharide extracts not only reversed the inhibitory effects of DFMO on cellular polyamine content and [Ca^(2+)]cyt, but also restored IEC-6 cell migration to control level(P < 0.01 or < 0.05). Kv1.1 mRNA and protein expressions were increased(P < 0.05) after polysaccharide extract treatment in polyamine-deficient IEC-6 cells and RhoA protein expression was increased. Molar ratios of D-ribose, D-arabinose, L-rhamnose, D-mannose, D-glucose, and D-galactose was 1.0:14.1:0.3:19.9:181.3:6.3 in RA and 1.0:4.3:0.1:5.7:2.8:2.2 in RAM. In conclusion, treatment with RA and RAM polysaccharide extracts stimulated migration of intestinal epithelial cells via a polyamine-Kv1.1 channel activated signaling pathway, which facilitated intestinal injury healing. 展开更多
关键词 Intestinal epithelial CELL (IEC-6) CELL migration POLYSACCHARIDE EXTRACTS Astragalus membranaceus Atractylodes macrocephala Polyamines K^%PLUS% channel
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Numerical study on pebble-bed powder migration and clogging mechanism with purge gas
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作者 Xue-Tao Cui Qi-Gang Wu +2 位作者 Jian Wang Ming-Zhun Lei Yun-Tao Song 《Nuclear Science and Techniques》 2026年第2期194-207,共14页
As the primary functional component of a fusion reactor,the fusion blanket pebble bed,composed of numerous particles,is crucial for tritium breeding,neutron multiplication,and radiation shielding.Particles within trit... As the primary functional component of a fusion reactor,the fusion blanket pebble bed,composed of numerous particles,is crucial for tritium breeding,neutron multiplication,and radiation shielding.Particles within tritium-breeding pebble beds are subjected to prolonged neutron irradiation,high thermal loads,and strong magnetic fields in fusion environments.Such conditions render them susceptible to pulverization and fragmentation.The resulting fragments and powders migrate and are deposited into the gas channel,driven by the purge gas.The reduction in the effective flow area of the gas increases the flow resistance,resulting in tritium retention,degraded heat transfer,and other adverse effects.These conditions impair the thermodynamic properties of the pebble beds and hinder the self-maintenance of tritium.Limited information exists on powder migration and clogging mechanisms in fusion blanket pebble beds,particularly under diverse physical conditions.The aim of this study was to use a computational fluid dynamics model coupled with the discrete element method(CFD-DEM)to numerically explore powder migration and clogging in pebble beds.The model considers factors such as breeder orientation,purge velocity,powder size distribution,and friction coefficient.We propose two migration and clogging mechanisms.One involves powder with a large particle size,and the other does not.The results indicate that the powder migration velocity progresses through three stages:rapid decay,linear decay,and stability.Pebble-bed clogging manifests in two forms:extensive superficial clogging and uniform internal clogging.Two fitted curves were used to depict the migration and clogging tendencies.The powder size distribution significantly influenced the powder migration.The breeder orientation,powder size,and friction coefficient affected the distribution of the clogging powders.However,the impact of the purge velocity on powder migration and clogging in pebble beds was limited,and this effect varied significantly with different particle size ratios.Based on the analysis,a formula is proposed to characterize the behavior of the powder in the pebble beds.The results of this study can aid in analyzing and predicting powder dynamics in pebble beds. 展开更多
关键词 Coupled CFD-DEM Pebble beds Purge gas Powder flow migration and clogging mechanism
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Early treadmill exercise increases macrophage migration inhibitory factor expression after cerebral ischemia/reperfusion 被引量:12
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作者 Min Cheol Chang Chae Ri Park +2 位作者 Seung Hwa Rhie Woo Hyun Shim Dae Yul Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第7期1230-1236,共7页
The neuroprotective function of macrophage migration inhibitory factor(MIF) in ischemic stroke was rarely evaluated.This study aimed to investigate the effects of early treadmill exercise on recovery from ischemic str... The neuroprotective function of macrophage migration inhibitory factor(MIF) in ischemic stroke was rarely evaluated.This study aimed to investigate the effects of early treadmill exercise on recovery from ischemic stroke and to determine whether these effects are associated with the expression levels of MIF and brain-derived neurotrophic factor(BDNF) in the ischemic area.A total of 40 male Sprague-Dawley rats were randomly assigned to the ischemia and exercise group [middle cerebral artery occlusion(MCAO)-Ex,n = 10),ischemia and sedentary group(MCAO-St,n = 10),sham-surgery and exercise group(Sham-Ex,n= 10),or sham-surgery and sedentary group(Sham-St,n = 10).The MCAO-Ex and MCAO-St groups were subjected to MCAO for 60 minutes,whereas the Sham-Ex and Sham-St groups were subjected to an identical operation without MCAO.Rats in the MCAO-Ex and Sham-Ex groups then ran on a treadmill for 30 minutes once a day for 5 consecutive days.After reperfusion,the hanging time tested by the wire hang test was longer and the relative fractional anisotropy determined by MRI was higher in the peri-infarct region of the MCAO-Ex group compared with the MCAO-St group.The expression levels of MIF and BDNF in the peri-infarct region were upregulated in the MCAO-Ex group.Increased MIF and BDNF levels were positively correlated with relative fractional anisotropy changes in the peri-infarct region.There was no significant difference in the levels of MIF and BDNF in the peri-infarct region between the Sham-Ex and Sham-St groups.Our study demonstrated that early exercise(initiated 48 hours after the MCAO) could improve motor and neuronal recovery after ischemic stroke.Furthermore,the increased levels of MIF and BDNF in the peri-infarct region(penumbra) may be one of the mechanisms of enhanced neurological function recovery.All experiments were approved by the Institutional Animal Care and Use Committee in Asan Medical Center in South Korea(2016-12-126). 展开更多
关键词 ischemic stroke EARLY exercise macrophage migration inhibitory FACTOR BRAIN-DERIVED NEUROTROPHIC FACTOR motor recovery neural regeneration
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Expression of macrophage migration inhibitory factor in Aspergillus fumigatus keratitis 被引量:2
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作者 Qiang Xu Li-Ting Hu +4 位作者 Qian Wang Jing Lin Nan Jiang Cui Li Gui-Qiu Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第5期711-716,共6页
AIM: To investigate the expression of macrophage migration inhibitory factor(MIF) and detect its role in the innate immune response of fungal keratitis(FK). METHODS: We collected the paraffin-embedded cornea tissues f... AIM: To investigate the expression of macrophage migration inhibitory factor(MIF) and detect its role in the innate immune response of fungal keratitis(FK). METHODS: We collected the paraffin-embedded cornea tissues from 10 FK and 6 ocular trauma patients to explore the MIF expression by immunohistochemistry. Then we cultured telomease-immortalized human corneal epithelial cells(THCEs), stimulated by the hyphae suspension of Aspergillus fumigatus(A. fumigatus) to detect the change of MIF with or without the pretreatment of MIF inhibitor [4-Iodo-6-phenylpyrimidine(4-IPP)] by real-time polymerase chain reaction(PCR). The protein level of MIF was also tested by immunohistochemistry, and the level of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) mRNA were compared between normal, hyphae stimulated and 4-IPP pretreated groups by real-time PCR to study the influence of MIF on the expression of TNF-α and IL-6. Corneal severity of rats' FK models was documented by clinical scores, and real-time PCR. Western blot and immunohistochemistry were used to test the expression of MIF, TNF-α and IL-6 in rats' corneas.RESULTS: In the corneas of FK patients, there was much stronger expression of MIF than that in the normal group showed by immunohistochemistry. In cultured THCEs stimulated by A. fumigatus, the expression of MIF became stronger in both immunohistochemistry and PCR at 16, 24, 32 and 48 h post infection(p.i.; P<0.01, P<0.01, P<0.01, P<0.05). After pretreated with 4-IPP, the expression of MIF reduced at 4, 8, 16 h p.i.(P<0.05, P<0.05, P<0.05) and the downstream TNF-α and IL-6 decreased obviously(P<0.05, P<0.01). In rats with A. fumigatus keratitis, the relative mRNA and protein level of MIF increased than thosein the normal group by PCR(at 1 d: P<0.01, 3 d: P<0.01, 5 d: P<0.01), Western blot and immunohistochemistry. After blocked MIF with 4-IPP, the clinical outcomes of rat keratitis showed markedly reduced inflammatory response(P<0.01), with TNF-α and IL-6 decreased in accordance with those in THCEs by PCR(P<0.05, P<0.01). CONCLUSION: The expression of MIF increased significantly in FK patients, THCEs and rats stimulated by A. fumigatus. After blocked with 4-IPP, the expression of MIF reduced, and so did its downstream cytokines: TNF-α and IL-6. The inflammation reaction of the rats' corneas lightened after pretreated with 4-IPP. MIF may play a role in the innate immune response of the corneal resistance against A. fumigatus. 展开更多
关键词 macrophage migration INHIBITORY factor FUNGAL KERATITIS INNATE immune A. FUMIGATUS CORNEAL epithelial cells rats
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