Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a ...Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a compatibilizer.The synergistic effects of the two additives on the mechanical,thermal,and morphological properties of the PLA/PBAT blend films were investigated.The influence of TEC content on the plasticized PLA films and the effect of TDI’s presence on the PLA/PBAT blend films were also studied by comparing them with neat PLA.The results showed a pronounced increase in elongation at break of the plasticized PLA films with increasing TEC levels,but a slight reduction in thermal stability.Also,the addition of TEC and TDI to the blend system not only synergistically enhanced the tensile properties and tensile-impact strength of the PLA/PBAT blends,but also affected their crystallinity and cold crystallization rate,a result of the improvement of interfacial interaction between PLA and PBAT,including the enhancement of their chain mobility.The synergy of the plasticization and compatibilization processes led to the improvement of tensile properties,tensile-impact strength,and compatibility of the blends,accelerating cold crystallization without affecting crystallization.展开更多
Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results...Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.展开更多
A plasticizer triethylene glycol maleate（TEG-MA） was synthesized. The dominated monoester of moderate hydrophobicity with apparent oil-water partition coefficient of 0.042 in the product was confirmed by acid value ...A plasticizer triethylene glycol maleate（TEG-MA） was synthesized. The dominated monoester of moderate hydrophobicity with apparent oil-water partition coefficient of 0.042 in the product was confirmed by acid value determination, HPLC and FTIR. Its plasticizing effect on oxidized starch was manifested by crystallization, aging behaviour, moisture absorption, and mechanical performance. X-ray diffraction data showed that the relative crystallinity of the plasticized starch decreased. Both the crystal and the crystallinity of starch films were rarely changed in aging. Moisture absorption relied on the ester content and relative humidity. The elongation at break increased significantly with plasticizer content more than 10% in the matrix.展开更多
The additives present in polyvinyl chloride(PVC)materials are the major source of organic by-products during PVC degradation.The thermal stabilizer and plasticizer are the main additives that endow PVC with the requir...The additives present in polyvinyl chloride(PVC)materials are the major source of organic by-products during PVC degradation.The thermal stabilizer and plasticizer are the main additives that endow PVC with the required properties during its processing.However,these two additives easily migrate when samples are obtained by physical mixing of the additives with PVC.This causes the reduction of PVC sample efficacy and the increase in the formation of organic by-products in the radiolysis process.In this work,two kinds of grafted PVC samples(tungoil derivative grafted PVC and Atz grafted PVC,abbreviated as P-GT4 and P-AZ3)were synthesized by chemical grafting of 3-amino-1,2,4-triazole(Atz)and tung-oil derivative on PVC,respectively.These two PVC samples were then blended at different mass ratios to obtain hybrid PVC materials with excellent plasticization,thermal stability and migration resistance ability.Differential scanning calorimetry(DSC),discoloration,Congo red test and thermogravimetric analysis(TGA)showed that when the mass ratio of P-GT4 to P-AZ3 in the mixed PVC resin was 1:3,the resulting P1:3-GT4-AZ3(P4)presented the best plasticization and thermal stability.The kinetics of thermal decomposition showed that the activation energy of P4 was much higher than that of the reference material[PVC/DOTP/CaSt2/ZnSt2,PVC/CZ41 for short]at mass lossα=20%and 80%.In addition,the leaching test showed that P4 material possessed excellent migration resistance ability.展开更多
Tributyl citrate （TBC） plasticizer has been selected to prepare the novel plasticized PC under different time and temperature. The TBC plasticization effect on PC T, mechanical properties and morphology has been inv...Tributyl citrate （TBC） plasticizer has been selected to prepare the novel plasticized PC under different time and temperature. The TBC plasticization effect on PC T, mechanical properties and morphology has been investigated by DMTA, DSC, tensile test and SEM. The results show that the TBC content in PC is controlled by plasticization time and temperature. The mass-loss test has conftnned a less lost rate of TBC in PC. The T declines gradually with increasing TBC content. The tensile modulus and strength of the plasticized PC also decrease with the increase of TBC content, and an approximate linear relationship is found to exist between the TBC content and the tensile modulus and strength. The SEM images show that significant changes have taken place on the surface and in the cross-section of plasticized thin PC sheet.展开更多
Pharmaceutical solid dosage forms are commonly coated to modify the release of drugs. Due to the disadvantages of coated single-unit dosage forms, such as occurrences of dose dumping and local irritation, coated multi...Pharmaceutical solid dosage forms are commonly coated to modify the release of drugs. Due to the disadvantages of coated single-unit dosage forms, such as occurrences of dose dumping and local irritation, coated multi-particulates are preferred.Coated multi-particulates can eventually be filled into capsules or compressed into tablets.展开更多
The photodegradation of thin films of poly (4-chlorostyrene) and poly (4-bromostyrene) with 265 nm radiation in the presence of oxygen and as a function of irradiation time has been studied mainly using fluorescence, ...The photodegradation of thin films of poly (4-chlorostyrene) and poly (4-bromostyrene) with 265 nm radiation in the presence of oxygen and as a function of irradiation time has been studied mainly using fluorescence, FT-IR, and UV-VIS spectroscopic techniques. The influence of phthalate and terephthalate plasticizers on photo-oxidative degradation was also investigated. Phthalate and terephthalate-plasticizers were found to increase the photodegradation processes in polymeric chains. On the other hand, the intensity of absorption was also found to increase with irradiation time and in the intensity of a new absorption band at longer wavelength. The appearance of new fluorescence bands in the irradiated polymer films can well indicate a possibility of photodegradation of polymer films. In addition, the observed increase in the intensities of the carbonyl and hydroxyl regions of the FT-IR spectra, providing evidence for the photodegradation as well as the photo-oxidation of polymeric chains. The increase in the analyzed ranges was attributed to the formation of alcohols, aliphatic ketones and to the increase in the number of (C=C) that resulted from hydrogen abstraction during chains - scission.展开更多
Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications wit...Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications with metabolic reprogramming.Nonetheless,the specific mechanisms and roles of this connection in astrocytes remain unclear.Therefore,this review aims to explore the role and specific mechanisms of lactate in the metabolic reprogramming of astrocytes in the central nervous system.The close relationship between epigenetic modifications and metabolic reprogramming was discussed.Therapeutic strategies for targeting metabolic reprogramming in astrocytes in the central nervous system were also outlined to guide future research in central nervous system diseases.In the nervous system,lactate plays an essential role.However,its mechanism of action as a bridge between metabolic reprogramming and epigenetic modifications in the nervous system requires future investigation.The involvement of lactate in epigenetic modifications is currently a hot research topic,especially in lactylation modification,a key determinant in this process.Lactate also indirectly regulates various epigenetic modifications,such as N6-methyladenosine,acetylation,ubiquitination,and phosphorylation modifications,which are closely linked to several neurological disorders.In addition,exploring the clinical applications and potential therapeutic strategies of lactic acid provides new insights for future neurological disease treatments.展开更多
Diamonds were formed in the mantle lithosphere,mostly at depths of 150~200km in the centres of Precambrian cratons,the buoyant ancient cores of continents.From there they were normally transported into the upper crust...Diamonds were formed in the mantle lithosphere,mostly at depths of 150~200km in the centres of Precambrian cratons,the buoyant ancient cores of continents.From there they were normally transported into the upper crust in kimberlite pipes whose diamonds are largely colourless and light yellow related to trace element N(Ia type),although brown,green,and more rarely blue-coloured diamonds are related to lattice defect and trace amounts of H,more rarely B and Ni.Pink diamonds are extremely rare in the approximately 90 diamondiferous pipes mined globally.Although small quantities have been discovered elsewhere,about 90%have been mined from the ca.1.3Ga Argyle diamond pipe in Western Australia,with the Arkhangelskaya diamond pipe in Russia the only other significant source.The pink colour at both Argyle and Arkhangelskaya is unrelated to trace elements and instead results from absorption of light from nanoscale(550nm)defects related to shear stress and plastic deformation.Macroscopically,defects are shown by glide planes,lamellae,and grain lines imposed on the originally colourless diamonds derived from their mantle source.The key question is why these defects were uniquely acquired in diamonds in the Argyle and Arkhangelskaya pipes.Unlike most diamondiferous pipes,Argyle is a rare diamondiferous volatile-rich lamproite pipe that was emplaced into the multiply deformed and rifted NNE-trending Halls Creek Orogen on the margin of the Kimberley Craton.Similarly,Arkhangelskaya in the Devonian Lomonosov kimberlite cluster is a volatile-rich low-Ti type kimberlite,a close relative to lamproite,that was emplaced into the multiply deformed Lapland-Kola Orogen on the rifted margin of the Kola Craton.These craton margins are underlain by subduction-induced volatile-enriched metasomatized mantle lithosphere in contrast to the more primeval mantle under craton centres.It is thus likely that shear stresses were exacerbated at Argyle and Arkangelskaya by rapid vertical emplacement of the anomalous volatile-enriched magmas at supercritical pressures and temperatures,that induced catastrophic phase separation of these volatiles and'mini seismic events'during rapid pressure drops during ascent from 200km depth to the surface.Such a mechanism is consistent with the presence of strongly resorbed and plastically deformed small brown industrial diamonds in the Argyle pipe.From a China perspective,it is potentially important that at 1.3Ga the alkaline Argyle pipe in northern Australia is placed adjacent to the North China Craton(NCC),with numerous world-class mineral deposits including the giant ca.1.4~1.2Ga alkaline Bayan Obo REE system on its margin.However,it is the southeastern margin of the Yangtze Craton and the Jiangnan Orogen with their lamproite pipes derived from metasomatized mantle lithosphere that present the most prospective regions for pink diamond occurrences.展开更多
The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves gl...The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves global alterations,making understanding plastic responses triggered by local damage difficult.One key feature of the dentate gyrus is that it contains a well-defined neurogenic niche,the subgranular zone,and beyond neurogenesis,newly born granule cells may maintain a“young”phenotype throughout life,adding to the plastic nature of the structure.Here,we present a novel experimental model of local brain damage in organotypic entorhino-hippocampal cultures that results in the activation of adjacent newly born granule cells.A small piece of filter paper was placed on the surface of the granule cell layer of the dentate gyrus,which evoked a foreign body reaction of astrocytes,along with the activation of local young neurons expressing doublecortin.Forty-eight hours after foreign body placement,the number of doublecortin-immunoreactive cells increased in the subgranular zone in the direct vicinity of the foreign body,whereas overall increased doublecortin immunoreactivity was observed in the granule cell layer and molecular layer of the dentate gyrus.Foreign body placement in the pyramidal layer of the CA1 region evoked a comparable local astroglial reaction but did not lead to an increase in doublecortin-immunoreactive in either the CA1 region or the adjacent dentate gyrus.Seven days after foreign body placement in the dentate gyrus,the increase in doublecortin-immunoreactivity was no longer observed,indicating the transient activation of young cells.However,7 days after foreign body placement,the number of doublecortin-immunoreactive granule cells coimmunoreactive for calbindin was lower than that under the control conditions.As calbindin is a marker for mature granule cells,this result suggests that activated young cells remain at a more immature stage following foreign body placement.Live imaging of retrovirally green fluorescent protein-labeled newly born granule cells revealed the orientation and growth of their dendrites toward the foreign body placement.This novel experimental model of foreign body placement in organotypic entorhino-hippocampal cultures could serve as a valuable tool for studying both glial reactivity and neuronal plasticity,specifically of newly born neurons under controlled in vitro conditions.展开更多
Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinso...Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease.展开更多
The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.H...The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.However,recent findings revealed that some forms of neural plasticity can show a reverse trend.Although plasticity is a well-preserved,transversal feature across the animal world,a variety of cell populations and mechanisms seem to have evolved to enable structural modifications to take place in widely different brains,likely as adaptations to selective pressures.Increasing evidence now indicates that a trade-off has occurred between regenerative(mostly stem cell–driven)plasticity and developmental(mostly juvenile)remodeling,with the latter primarily aimed not at brain repair but rather at“sculpting”the neural circuits based on experience.In particular,an evolutionary trade-off has occurred between neurogenic processes intended to support the possibility of recruiting new neurons throughout life and the different ways of obtaining new neurons,and between the different brain locations in which plasticity occurs.This review first briefly surveys the different types of plasticity and the complexity of their possible outcomes and then focuses on recent findings showing that the mammalian brain has a stem cell–independent integration of new neurons into pre-existing(mature)neural circuits.This process is still largely unknown but involves neuronal cells that have been blocked in arrested maturation since their embryonic origin(also termed“immature”or“dormant”neurons).These cells can then restart maturation throughout the animal's lifespan to become functional neurons in brain regions,such as the cerebral cortex and amygdala,that are relevant to high-order cognition and emotions.Unlike stem cell–driven postnatal/adult neurogenesis,which significantly decreases from small-brained,short-living species to large-brained ones,immature neurons are particularly abundant in large-brained,long-living mammals,including humans.The immature neural cell populations hosted in these complex brains are an interesting example of an“enlarged road”in the phylogenetic trend of plastic potential decreases commonly observed in the animal world.The topic of dormant neurons that covary with brain size and gyrencephaly represents a prospective turning point in the field of neuroplasticity,with important translational outcomes.These cells can represent a reservoir of undifferentiated neurons,potentially granting plasticity within the high-order circuits subserving the most sophisticated cognitive skills that are important in the growing brains of young,healthy individuals and are frequently affected by debilitating neurodevelopmental and degenerative disorders.展开更多
Regenerative capacity of the central nervous system(CNS)is unevenly distributed among vertebrates.While most mammalian species including humans elicit limited repair following CNS injury or disease,highly regenerative...Regenerative capacity of the central nervous system(CNS)is unevenly distributed among vertebrates.While most mammalian species including humans elicit limited repair following CNS injury or disease,highly regenerative vertebrates including urodele amphibians and teleost fish spontaneously reverse CNS damage.Teletost zebrafish(danio rerio)are tropical freshwater fish that proved to be an excellent vertebrate model of successful CNS regeneration.Differential neuronal,glial,and immune injury responses underlie disparate injury outcomes between highly regenerative zebrafish and poorly regenerative mammals.This article describes complications associated with neuronal repair following spinal cord injury(SCI)in poorly regenerative mammals and highlights intersecting modes of plasticity and regeneration in highly regenerative zebrafish(Figures 1 and 2).Comparative approaches evaluating immunoglial SCI responses were recently reviewed elsewhere(Reyes and Mokalled,2024).展开更多
Multisensory integration allows biological organisms to merge information from various sensory modalities,enhancing perception,decision-making,and adaptability in complex environments.This process,involving specialize...Multisensory integration allows biological organisms to merge information from various sensory modalities,enhancing perception,decision-making,and adaptability in complex environments.This process,involving specialized cortical and subcortical areas,reduces uncertainty,speeds up responses,enriches perception,and supports adaptive behaviors.Recent findings reveal that even primary sensory cortices contribute to multisensory processing,further boosting adaptability and decisionmaking.Inspired by these natural capabilities,researchers aim to develop artificial systems replicating biological sensory integration to address challenges in robotics,artificial intelligence,and big data.Current artificial systems,often reliant on single-modal perception,struggle in dynamic environments due to their limited adaptability.Advances in materials,device architectures,and neuromorphic technologies,such as memristor-and transistor-based neurons,are enabling the development of multimodal systems with enhanced efficiency,flexibility,and functionality.This review explores strategies to overcome single-modal limitations,focusing on synchronization,fusion,and deep interpretation of sensory data.Future directions emphasize improving integration density,novel device designs,and adaptable mechanisms.Multimodal systems hold promise to revolutionize artificial perception,narrowing the gap between biological systems and intelligent technologies.展开更多
Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglio...Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglion cells and their axons,leading to axonal transport dysfuntion,subsequently causing secondary damage to anterior or posterior ends of the visual system.Accordingly,recent evidence indicates that glaucoma is a degenerative disease of the central nervous system that causes damage throughout the visual pathway.However,the effects of glaucoma on synaptic plasticity in the primary visual cortex remain unclear.In this study,we established a mouse model of unilateral chronic ocular hypertension by injecting magnetic microbeads into the anterior chamber of one eye.We found that,after 4 weeks of chronic ocular hypertension,the neuronal somas were smaller in the superior colliculus and lateral geniculate body regions of the brain contralateral to the affected eye.This was accompanied by glial cell activation and increased expression of inflammatory factors.After 8 weeks of ocular hypertension,we observed a reduction in the number of excitatory and inhibitory synapses,dendritic spines,and activation of glial cells in the primary visual cortex contralateral to the affected eye.These findings suggest that glaucoma not only directly damages the retina but also induces alterations in synapses and dendritic spines in the primary visual cortex,providing new insights into the pathogenesis of glaucoma.展开更多
Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune check...Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune checkpoint-T cell”axis.Collagen not only constitutes a mechanical barrier that distinguishes between the periphery and core of solid tumors but also systematically remodels the orientation of metabolism,vasculature,and immune cell phenotypic plasticity through its spatial density,fiber arrangement,and crosslinking patterns(F igure 1)[1,2].Abundant evidence suggests that over-accumulated types I and III collagen drive CD8+T cell exhaustion,NK cell functional inhibition,and tumor-associated macrophage polarization through ligand-receptor networks involving LAIR-1,DDR2,andβ1/β3 integrins[3-6].Mechanistically,collagen engagement of LAIR-1 delivers inhibitory signals in effector lymphocytes,promoting dysfunctional or exhausted states[7-9].In parallel,collagen-β1/β3 integrin signaling activates mechanotransduction pathways(e.g.,FAK/SRC),reducing T-cell motility and immune-tumor contact,while DDR2 activation supports matrix-remodeling programs that limit lymphocyte trafficking.展开更多
Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise,thereby adjusting the panel's stiffness.Since each layer of the composite may...Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise,thereby adjusting the panel's stiffness.Since each layer of the composite may be affected by a different failure mode,the optimal fiber volume fraction to suppress damage initiation and evolution is different across the layers.This research examines how re-allocating the fibers layer-wise enhances the composites'impact resistance.In this study,constant stiffness panels with the same fiber volume fraction throughout the layers are compared to variable stiffness ones by varying volume fraction layer-wise.A method is established that utilizes numerical analysis coupled with optimization techniques to determine the optimal fiber volume fraction in both scenarios.Three different reinforcement fibers(Kevlar,carbon,and glass)embedded in epoxy resin were studied.Panels were manufactured and tested under various loading conditions to validate results.Kevlar reinforcement revealed the highest tensile toughness,followed by carbon and then glass fibers.Varying reinforcement volume fraction significantly influences failure modes.Higher fractions lead to matrix cracking and debonding,while lower fractions result in more fiber breakage.The optimal volume fraction for maximizing fiber breakage energy is around 45%,whereas it is about 90%for matrix cracking and debonding.A drop tower test was used to examine the composite structure's behavior under lowvelocity impact,confirming the superiority of Kevlar-reinforced composites with variable stiffness.Conversely,glass-reinforced composites with constant stiffness revealed the lowest performance with the highest deflection.Across all reinforcement materials,the variable stiffness structure consistently outperformed its constant stiffness counterpart.展开更多
The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory ...The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory fibers.While the reticulospinal tract has been shown to be particularly prone to axonal growth and plasticity following injuries of the spinal cord,the differential capacities of excitatory and inhibitory fibers for plasticity remain unclear.As adaptive axonal plasticity involves a sophisticated interplay between excitatory and inhibitory input,we investigated in this study the plastic potential of glutamatergic(vGlut2)and GABAergic(vGat)fibers originating from the gigantocellular nucleus and the lateral paragigantocellular nucleus,two nuclei important for locomotor function.Using a combination of viral tracing,chemogenetic silencing,and AI-based kinematic analysis,we investigated plasticity and its impact on functional recovery within the first 3 weeks following injury,a period prone to neuronal remodeling.We demonstrate that,in this time frame,while vGlut2-positive fibers within the gigantocellular and lateral paragigantocellular nuclei rewire significantly following cervical spinal cord injury,vGat-positive fibers are rather unresponsive to injury.We also show that the acute silencing of excitatory axonal fibers which rewire in response to lesions of the spinal cord triggers a worsening of the functional recovery.Using kinematic analysis,we also pinpoint the locomotion features associated with the gigantocellular nucleus or lateral paragigantocellular nucleus during functional recovery.Overall,our study increases the understanding of the role of the gigantocellular and lateral paragigantocellular nuclei during functional recovery following spinal cord injury.展开更多
Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery ...Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.展开更多
基金financially supported by Development and Promotion of Science and Technology Talents (DPST) (No. 013/2559)
文摘Polylactide(PLA)films blended with poly(butylene adipate-co-terephthalate)(PBAT)were hot melted using a twin screw extruder with the addition of triethyl citrate(TEC)as a plasticizer and toluene diisocyanate(TDI)as a compatibilizer.The synergistic effects of the two additives on the mechanical,thermal,and morphological properties of the PLA/PBAT blend films were investigated.The influence of TEC content on the plasticized PLA films and the effect of TDI’s presence on the PLA/PBAT blend films were also studied by comparing them with neat PLA.The results showed a pronounced increase in elongation at break of the plasticized PLA films with increasing TEC levels,but a slight reduction in thermal stability.Also,the addition of TEC and TDI to the blend system not only synergistically enhanced the tensile properties and tensile-impact strength of the PLA/PBAT blends,but also affected their crystallinity and cold crystallization rate,a result of the improvement of interfacial interaction between PLA and PBAT,including the enhancement of their chain mobility.The synergy of the plasticization and compatibilization processes led to the improvement of tensile properties,tensile-impact strength,and compatibility of the blends,accelerating cold crystallization without affecting crystallization.
基金Funded by the Fundamental Research Funds for the Central Universities(DL13CB13)the China Postdoctoral Science Foundation Funded Project(No.2014M550178)the National Natural Science Foundation of China(No.31200442)
文摘Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.
基金Funded by Science and Technology Support Project of Sichuan Province(Nos.2014GZ0136 and 2015GZ0176)National Natural Science Foundation of China(No.51603134)
文摘A plasticizer triethylene glycol maleate（TEG-MA） was synthesized. The dominated monoester of moderate hydrophobicity with apparent oil-water partition coefficient of 0.042 in the product was confirmed by acid value determination, HPLC and FTIR. Its plasticizing effect on oxidized starch was manifested by crystallization, aging behaviour, moisture absorption, and mechanical performance. X-ray diffraction data showed that the relative crystallinity of the plasticized starch decreased. Both the crystal and the crystallinity of starch films were rarely changed in aging. Moisture absorption relied on the ester content and relative humidity. The elongation at break increased significantly with plasticizer content more than 10% in the matrix.
基金the National Natural Science Foundation of China(21905117)Guangxi Key Laboratory of Chemistry and Engineering of Forest Products(GXFK2203)and the Natural Science Foundation of Jiangsu Province(BK20201128)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘The additives present in polyvinyl chloride(PVC)materials are the major source of organic by-products during PVC degradation.The thermal stabilizer and plasticizer are the main additives that endow PVC with the required properties during its processing.However,these two additives easily migrate when samples are obtained by physical mixing of the additives with PVC.This causes the reduction of PVC sample efficacy and the increase in the formation of organic by-products in the radiolysis process.In this work,two kinds of grafted PVC samples(tungoil derivative grafted PVC and Atz grafted PVC,abbreviated as P-GT4 and P-AZ3)were synthesized by chemical grafting of 3-amino-1,2,4-triazole(Atz)and tung-oil derivative on PVC,respectively.These two PVC samples were then blended at different mass ratios to obtain hybrid PVC materials with excellent plasticization,thermal stability and migration resistance ability.Differential scanning calorimetry(DSC),discoloration,Congo red test and thermogravimetric analysis(TGA)showed that when the mass ratio of P-GT4 to P-AZ3 in the mixed PVC resin was 1:3,the resulting P1:3-GT4-AZ3(P4)presented the best plasticization and thermal stability.The kinetics of thermal decomposition showed that the activation energy of P4 was much higher than that of the reference material[PVC/DOTP/CaSt2/ZnSt2,PVC/CZ41 for short]at mass lossα=20%and 80%.In addition,the leaching test showed that P4 material possessed excellent migration resistance ability.
基金Funded by the Natural Science Foundation of Hubei Province(No.2010CDB04604)
文摘Tributyl citrate （TBC） plasticizer has been selected to prepare the novel plasticized PC under different time and temperature. The TBC plasticization effect on PC T, mechanical properties and morphology has been investigated by DMTA, DSC, tensile test and SEM. The results show that the TBC content in PC is controlled by plasticization time and temperature. The mass-loss test has conftnned a less lost rate of TBC in PC. The T declines gradually with increasing TBC content. The tensile modulus and strength of the plasticized PC also decrease with the increase of TBC content, and an approximate linear relationship is found to exist between the TBC content and the tensile modulus and strength. The SEM images show that significant changes have taken place on the surface and in the cross-section of plasticized thin PC sheet.
文摘Pharmaceutical solid dosage forms are commonly coated to modify the release of drugs. Due to the disadvantages of coated single-unit dosage forms, such as occurrences of dose dumping and local irritation, coated multi-particulates are preferred.Coated multi-particulates can eventually be filled into capsules or compressed into tablets.
文摘The photodegradation of thin films of poly (4-chlorostyrene) and poly (4-bromostyrene) with 265 nm radiation in the presence of oxygen and as a function of irradiation time has been studied mainly using fluorescence, FT-IR, and UV-VIS spectroscopic techniques. The influence of phthalate and terephthalate plasticizers on photo-oxidative degradation was also investigated. Phthalate and terephthalate-plasticizers were found to increase the photodegradation processes in polymeric chains. On the other hand, the intensity of absorption was also found to increase with irradiation time and in the intensity of a new absorption band at longer wavelength. The appearance of new fluorescence bands in the irradiated polymer films can well indicate a possibility of photodegradation of polymer films. In addition, the observed increase in the intensities of the carbonyl and hydroxyl regions of the FT-IR spectra, providing evidence for the photodegradation as well as the photo-oxidation of polymeric chains. The increase in the analyzed ranges was attributed to the formation of alcohols, aliphatic ketones and to the increase in the number of (C=C) that resulted from hydrogen abstraction during chains - scission.
基金supported by the National Natural Science Foundation of China,Nos.82071383,82371392(to BN)the Natural Science Foundation of Shandong Province of China(Key Project),No.ZR2020KH007(to BN)+1 种基金“Taishan Scholar Distinguished Expert Program”of Shandong Province,No.tstp20231257(to BN)Health Commission Science and Technology Plan Project of Jinan,No.2023-1-8(to YZ).
文摘Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications with metabolic reprogramming.Nonetheless,the specific mechanisms and roles of this connection in astrocytes remain unclear.Therefore,this review aims to explore the role and specific mechanisms of lactate in the metabolic reprogramming of astrocytes in the central nervous system.The close relationship between epigenetic modifications and metabolic reprogramming was discussed.Therapeutic strategies for targeting metabolic reprogramming in astrocytes in the central nervous system were also outlined to guide future research in central nervous system diseases.In the nervous system,lactate plays an essential role.However,its mechanism of action as a bridge between metabolic reprogramming and epigenetic modifications in the nervous system requires future investigation.The involvement of lactate in epigenetic modifications is currently a hot research topic,especially in lactylation modification,a key determinant in this process.Lactate also indirectly regulates various epigenetic modifications,such as N6-methyladenosine,acetylation,ubiquitination,and phosphorylation modifications,which are closely linked to several neurological disorders.In addition,exploring the clinical applications and potential therapeutic strategies of lactic acid provides new insights for future neurological disease treatments.
文摘Diamonds were formed in the mantle lithosphere,mostly at depths of 150~200km in the centres of Precambrian cratons,the buoyant ancient cores of continents.From there they were normally transported into the upper crust in kimberlite pipes whose diamonds are largely colourless and light yellow related to trace element N(Ia type),although brown,green,and more rarely blue-coloured diamonds are related to lattice defect and trace amounts of H,more rarely B and Ni.Pink diamonds are extremely rare in the approximately 90 diamondiferous pipes mined globally.Although small quantities have been discovered elsewhere,about 90%have been mined from the ca.1.3Ga Argyle diamond pipe in Western Australia,with the Arkhangelskaya diamond pipe in Russia the only other significant source.The pink colour at both Argyle and Arkhangelskaya is unrelated to trace elements and instead results from absorption of light from nanoscale(550nm)defects related to shear stress and plastic deformation.Macroscopically,defects are shown by glide planes,lamellae,and grain lines imposed on the originally colourless diamonds derived from their mantle source.The key question is why these defects were uniquely acquired in diamonds in the Argyle and Arkhangelskaya pipes.Unlike most diamondiferous pipes,Argyle is a rare diamondiferous volatile-rich lamproite pipe that was emplaced into the multiply deformed and rifted NNE-trending Halls Creek Orogen on the margin of the Kimberley Craton.Similarly,Arkhangelskaya in the Devonian Lomonosov kimberlite cluster is a volatile-rich low-Ti type kimberlite,a close relative to lamproite,that was emplaced into the multiply deformed Lapland-Kola Orogen on the rifted margin of the Kola Craton.These craton margins are underlain by subduction-induced volatile-enriched metasomatized mantle lithosphere in contrast to the more primeval mantle under craton centres.It is thus likely that shear stresses were exacerbated at Argyle and Arkangelskaya by rapid vertical emplacement of the anomalous volatile-enriched magmas at supercritical pressures and temperatures,that induced catastrophic phase separation of these volatiles and'mini seismic events'during rapid pressure drops during ascent from 200km depth to the surface.Such a mechanism is consistent with the presence of strongly resorbed and plastically deformed small brown industrial diamonds in the Argyle pipe.From a China perspective,it is potentially important that at 1.3Ga the alkaline Argyle pipe in northern Australia is placed adjacent to the North China Craton(NCC),with numerous world-class mineral deposits including the giant ca.1.4~1.2Ga alkaline Bayan Obo REE system on its margin.However,it is the southeastern margin of the Yangtze Craton and the Jiangnan Orogen with their lamproite pipes derived from metasomatized mantle lithosphere that present the most prospective regions for pink diamond occurrences.
基金funded by the Alexander von Humboldt Stiftungsupported by DFG (SCH W534/6-1 to SWS)
文摘The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves global alterations,making understanding plastic responses triggered by local damage difficult.One key feature of the dentate gyrus is that it contains a well-defined neurogenic niche,the subgranular zone,and beyond neurogenesis,newly born granule cells may maintain a“young”phenotype throughout life,adding to the plastic nature of the structure.Here,we present a novel experimental model of local brain damage in organotypic entorhino-hippocampal cultures that results in the activation of adjacent newly born granule cells.A small piece of filter paper was placed on the surface of the granule cell layer of the dentate gyrus,which evoked a foreign body reaction of astrocytes,along with the activation of local young neurons expressing doublecortin.Forty-eight hours after foreign body placement,the number of doublecortin-immunoreactive cells increased in the subgranular zone in the direct vicinity of the foreign body,whereas overall increased doublecortin immunoreactivity was observed in the granule cell layer and molecular layer of the dentate gyrus.Foreign body placement in the pyramidal layer of the CA1 region evoked a comparable local astroglial reaction but did not lead to an increase in doublecortin-immunoreactive in either the CA1 region or the adjacent dentate gyrus.Seven days after foreign body placement in the dentate gyrus,the increase in doublecortin-immunoreactivity was no longer observed,indicating the transient activation of young cells.However,7 days after foreign body placement,the number of doublecortin-immunoreactive granule cells coimmunoreactive for calbindin was lower than that under the control conditions.As calbindin is a marker for mature granule cells,this result suggests that activated young cells remain at a more immature stage following foreign body placement.Live imaging of retrovirally green fluorescent protein-labeled newly born granule cells revealed the orientation and growth of their dendrites toward the foreign body placement.This novel experimental model of foreign body placement in organotypic entorhino-hippocampal cultures could serve as a valuable tool for studying both glial reactivity and neuronal plasticity,specifically of newly born neurons under controlled in vitro conditions.
基金financially supported by King Abdulaziz University,Deanship of Scientific Research(DSR)。
文摘Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease.
基金supported by Progetto Trapezio,Compagnia di San Paolo(67935-2021.2174),to LBFondazione CRT(Cassa di Risparmio di Torino,RF=2022.0618),to LBPRIN2022(grant 2022LB4X3N),to LB。
文摘The capacity of the central nervous system for structural plasticity and regeneration is commonly believed to show a decreasing progression from“small and simple”brains to the larger,more complex brains of mammals.However,recent findings revealed that some forms of neural plasticity can show a reverse trend.Although plasticity is a well-preserved,transversal feature across the animal world,a variety of cell populations and mechanisms seem to have evolved to enable structural modifications to take place in widely different brains,likely as adaptations to selective pressures.Increasing evidence now indicates that a trade-off has occurred between regenerative(mostly stem cell–driven)plasticity and developmental(mostly juvenile)remodeling,with the latter primarily aimed not at brain repair but rather at“sculpting”the neural circuits based on experience.In particular,an evolutionary trade-off has occurred between neurogenic processes intended to support the possibility of recruiting new neurons throughout life and the different ways of obtaining new neurons,and between the different brain locations in which plasticity occurs.This review first briefly surveys the different types of plasticity and the complexity of their possible outcomes and then focuses on recent findings showing that the mammalian brain has a stem cell–independent integration of new neurons into pre-existing(mature)neural circuits.This process is still largely unknown but involves neuronal cells that have been blocked in arrested maturation since their embryonic origin(also termed“immature”or“dormant”neurons).These cells can then restart maturation throughout the animal's lifespan to become functional neurons in brain regions,such as the cerebral cortex and amygdala,that are relevant to high-order cognition and emotions.Unlike stem cell–driven postnatal/adult neurogenesis,which significantly decreases from small-brained,short-living species to large-brained ones,immature neurons are particularly abundant in large-brained,long-living mammals,including humans.The immature neural cell populations hosted in these complex brains are an interesting example of an“enlarged road”in the phylogenetic trend of plastic potential decreases commonly observed in the animal world.The topic of dormant neurons that covary with brain size and gyrencephaly represents a prospective turning point in the field of neuroplasticity,with important translational outcomes.These cells can represent a reservoir of undifferentiated neurons,potentially granting plasticity within the high-order circuits subserving the most sophisticated cognitive skills that are important in the growing brains of young,healthy individuals and are frequently affected by debilitating neurodevelopmental and degenerative disorders.
文摘Regenerative capacity of the central nervous system(CNS)is unevenly distributed among vertebrates.While most mammalian species including humans elicit limited repair following CNS injury or disease,highly regenerative vertebrates including urodele amphibians and teleost fish spontaneously reverse CNS damage.Teletost zebrafish(danio rerio)are tropical freshwater fish that proved to be an excellent vertebrate model of successful CNS regeneration.Differential neuronal,glial,and immune injury responses underlie disparate injury outcomes between highly regenerative zebrafish and poorly regenerative mammals.This article describes complications associated with neuronal repair following spinal cord injury(SCI)in poorly regenerative mammals and highlights intersecting modes of plasticity and regeneration in highly regenerative zebrafish(Figures 1 and 2).Comparative approaches evaluating immunoglial SCI responses were recently reviewed elsewhere(Reyes and Mokalled,2024).
基金the Hong Kong Research Grants Council,Young Collaborative Research Grant(No.C5001-24)Research Institute for Smart Energy(No.UCDC9)+10 种基金Guangdong Provincial Department of Science and Technology(No.2024B1515040002)RSC Sustainable Laboratories Grant(No.L24-8215098370)Guangdong Basic and Applied Basic Research Foundation(No.2023A1515012479)the Science and Technology Innovation Commission of Shenzhen(No.JCYJ20220818100206013)RSC Researcher Collaborations Grant(No.C23-2422436283)State Key Laboratory of Radio Frequency Heterogeneous Integration(Independent Scientific Research Program No.2024010)NTUT-SZU Joint Research Programsupported by the National Natural Science Foundation of China(No.52373248)Guangdong Provincial Department of Science and Technology(Nos.2024A1515010006 and 2024A1515011718)Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515012479 and 2025A1515011274)the Science and Technology Innovation Commission of Shenzhen(Nos.JCYJ20230808105900001,JCYJ20220531102214032,20231123155543001,and JCYJ20240813141813018).
文摘Multisensory integration allows biological organisms to merge information from various sensory modalities,enhancing perception,decision-making,and adaptability in complex environments.This process,involving specialized cortical and subcortical areas,reduces uncertainty,speeds up responses,enriches perception,and supports adaptive behaviors.Recent findings reveal that even primary sensory cortices contribute to multisensory processing,further boosting adaptability and decisionmaking.Inspired by these natural capabilities,researchers aim to develop artificial systems replicating biological sensory integration to address challenges in robotics,artificial intelligence,and big data.Current artificial systems,often reliant on single-modal perception,struggle in dynamic environments due to their limited adaptability.Advances in materials,device architectures,and neuromorphic technologies,such as memristor-and transistor-based neurons,are enabling the development of multimodal systems with enhanced efficiency,flexibility,and functionality.This review explores strategies to overcome single-modal limitations,focusing on synchronization,fusion,and deep interpretation of sensory data.Future directions emphasize improving integration density,novel device designs,and adaptable mechanisms.Multimodal systems hold promise to revolutionize artificial perception,narrowing the gap between biological systems and intelligent technologies.
基金supported by the National Natural Science Foundation of China,No.82271115(to MY).
文摘Synaptic plasticity is essential for maintaining neuronal function in the central nervous system and serves as a critical indicator of the effects of neurodegenerative disease.Glaucoma directly impairs retinal ganglion cells and their axons,leading to axonal transport dysfuntion,subsequently causing secondary damage to anterior or posterior ends of the visual system.Accordingly,recent evidence indicates that glaucoma is a degenerative disease of the central nervous system that causes damage throughout the visual pathway.However,the effects of glaucoma on synaptic plasticity in the primary visual cortex remain unclear.In this study,we established a mouse model of unilateral chronic ocular hypertension by injecting magnetic microbeads into the anterior chamber of one eye.We found that,after 4 weeks of chronic ocular hypertension,the neuronal somas were smaller in the superior colliculus and lateral geniculate body regions of the brain contralateral to the affected eye.This was accompanied by glial cell activation and increased expression of inflammatory factors.After 8 weeks of ocular hypertension,we observed a reduction in the number of excitatory and inhibitory synapses,dendritic spines,and activation of glial cells in the primary visual cortex contralateral to the affected eye.These findings suggest that glaucoma not only directly damages the retina but also induces alterations in synapses and dendritic spines in the primary visual cortex,providing new insights into the pathogenesis of glaucoma.
文摘Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune checkpoint-T cell”axis.Collagen not only constitutes a mechanical barrier that distinguishes between the periphery and core of solid tumors but also systematically remodels the orientation of metabolism,vasculature,and immune cell phenotypic plasticity through its spatial density,fiber arrangement,and crosslinking patterns(F igure 1)[1,2].Abundant evidence suggests that over-accumulated types I and III collagen drive CD8+T cell exhaustion,NK cell functional inhibition,and tumor-associated macrophage polarization through ligand-receptor networks involving LAIR-1,DDR2,andβ1/β3 integrins[3-6].Mechanistically,collagen engagement of LAIR-1 delivers inhibitory signals in effector lymphocytes,promoting dysfunctional or exhausted states[7-9].In parallel,collagen-β1/β3 integrin signaling activates mechanotransduction pathways(e.g.,FAK/SRC),reducing T-cell motility and immune-tumor contact,while DDR2 activation supports matrix-remodeling programs that limit lymphocyte trafficking.
基金funded by the American University of Sharjah.United Arab Emirates award number EN 9502-FRG19-M-E75。
文摘Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise,thereby adjusting the panel's stiffness.Since each layer of the composite may be affected by a different failure mode,the optimal fiber volume fraction to suppress damage initiation and evolution is different across the layers.This research examines how re-allocating the fibers layer-wise enhances the composites'impact resistance.In this study,constant stiffness panels with the same fiber volume fraction throughout the layers are compared to variable stiffness ones by varying volume fraction layer-wise.A method is established that utilizes numerical analysis coupled with optimization techniques to determine the optimal fiber volume fraction in both scenarios.Three different reinforcement fibers(Kevlar,carbon,and glass)embedded in epoxy resin were studied.Panels were manufactured and tested under various loading conditions to validate results.Kevlar reinforcement revealed the highest tensile toughness,followed by carbon and then glass fibers.Varying reinforcement volume fraction significantly influences failure modes.Higher fractions lead to matrix cracking and debonding,while lower fractions result in more fiber breakage.The optimal volume fraction for maximizing fiber breakage energy is around 45%,whereas it is about 90%for matrix cracking and debonding.A drop tower test was used to examine the composite structure's behavior under lowvelocity impact,confirming the superiority of Kevlar-reinforced composites with variable stiffness.Conversely,glass-reinforced composites with constant stiffness revealed the lowest performance with the highest deflection.Across all reinforcement materials,the variable stiffness structure consistently outperformed its constant stiffness counterpart.
基金supported by the Deutsche Forschungsgemeinschaft(DFG),TRR274(Project ID 408885537,Sy Nergy,EXC 2145/ID 390857198,to FMB)。
文摘The remodeling of axonal connections following injury is an important feature driving functional recovery.The reticulospinal tract is an interesting descending motor tract that contains both excitatory and inhibitory fibers.While the reticulospinal tract has been shown to be particularly prone to axonal growth and plasticity following injuries of the spinal cord,the differential capacities of excitatory and inhibitory fibers for plasticity remain unclear.As adaptive axonal plasticity involves a sophisticated interplay between excitatory and inhibitory input,we investigated in this study the plastic potential of glutamatergic(vGlut2)and GABAergic(vGat)fibers originating from the gigantocellular nucleus and the lateral paragigantocellular nucleus,two nuclei important for locomotor function.Using a combination of viral tracing,chemogenetic silencing,and AI-based kinematic analysis,we investigated plasticity and its impact on functional recovery within the first 3 weeks following injury,a period prone to neuronal remodeling.We demonstrate that,in this time frame,while vGlut2-positive fibers within the gigantocellular and lateral paragigantocellular nuclei rewire significantly following cervical spinal cord injury,vGat-positive fibers are rather unresponsive to injury.We also show that the acute silencing of excitatory axonal fibers which rewire in response to lesions of the spinal cord triggers a worsening of the functional recovery.Using kinematic analysis,we also pinpoint the locomotion features associated with the gigantocellular nucleus or lateral paragigantocellular nucleus during functional recovery.Overall,our study increases the understanding of the role of the gigantocellular and lateral paragigantocellular nuclei during functional recovery following spinal cord injury.
基金supported by the NIH (R01NS103481, R01NS111776, and R01NS131489)Indiana Department of Health (ISDH58180)(all to WW)。
文摘Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.
