Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of sev...Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of severe liver disease or cirrhosis.Previous studies have reported spatially distributed structural and functional abnormalities related to HE,but the exact relationship between the structural and functional alterations with respect to disease progression remains unclear.In this study,we performed surface-based cortical thickness comparisons and functional connectivity(FC)analyses between three cross-sectional groups:healthy controls(HC,N¼51),patients with minimal hepatic en-cephalopathy(MHE,N¼50),patients with overt hepatic encephalopathy(OHE,N¼51).In addition to the distributed cortical thinning that is extensively thought to be associated with cognitive decline in HE,we found significant cortical thickening in the left para-hippocampal gyrus cortex in the OHE group(p<0.001,p¼0.009)as compared to the HC and MHE group respectively,which is further corroborated by the significant correlation between the cortical thickness and digit symbol test(DST)scores.Furthermore,the decreased FC between the right postcentral gyrus and several sensory regions(bilateral somatosensory and visual cortices)was found to be significant in MHE patients as compared to the HC group.Our results revealed cross-sectional structural and functional variations concerning disease progression across different subsystems(e.g.,visual,motor and sensory),providing evidence that can potentially explain the mechanisms underlying the sensorimotor and cognitive deficits related to HE.展开更多
After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the tim...After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions.展开更多
The hippocampus is part of the brain limbic system and plays an important role in learning and memory.Moreover,its ability to form,consolidate,and retrieve different types of memories makes it a central component in t...The hippocampus is part of the brain limbic system and plays an important role in learning and memory.Moreover,its ability to form,consolidate,and retrieve different types of memories makes it a central component in the cognitive functions necessary for everyday life.Understanding the role of the hippocampus helps comprehend how memories are created,stored,and recalled and sheds light on the impact of hippocampal damage in conditions such as Alzheimer’s disease and other forms of dementia.展开更多
The thermal conductivity of nanofluids is an important property that influences the heat transfer capabilities of nanofluids.Researchers rely on experimental investigations to explore nanofluid properties,as it is a n...The thermal conductivity of nanofluids is an important property that influences the heat transfer capabilities of nanofluids.Researchers rely on experimental investigations to explore nanofluid properties,as it is a necessary step before their practical application.As these investigations are time and resource-consuming undertakings,an effective prediction model can significantly improve the efficiency of research operations.In this work,an Artificial Neural Network(ANN)model is developed to predict the thermal conductivity of metal oxide water-based nanofluid.For this,a comprehensive set of 691 data points was collected from the literature.This dataset is split into training(70%),validation(15%),and testing(15%)and used to train the ANN model.The developed model is a backpropagation artificial neural network with a 4–12–1 architecture.The performance of the developed model shows high accuracy with R values above 0.90 and rapid convergence.It shows that the developed ANN model accurately predicts the thermal conductivity of nanofluids.展开更多
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
Epilepsy,a common neurological disorder,is characterized by recurrent seizures that can lead to cognitive,psychological,and neurobiological consequences.The pathogenesis of epilepsy involves neuronal dysfunction at th...Epilepsy,a common neurological disorder,is characterized by recurrent seizures that can lead to cognitive,psychological,and neurobiological consequences.The pathogenesis of epilepsy involves neuronal dysfunction at the molecular,cellular,and neural circuit levels.Abnormal molecular signaling pathways or dysfunction of specific cell types can lead to epilepsy by disrupting the normal functioning of neural circuits.The continuous emergence of new technologies and the rapid advancement of existing ones have facilitated the discovery and comprehensive understanding of the neural circuit mechanisms underlying epilepsy.Therefore,this review aims to investigate the current understanding of the neural circuit mechanisms in epilepsy based on various technologies,including electroencephalography,magnetic resonance imaging,optogenetics,chemogenetics,deep brain stimulation,and brain-computer interfaces.Additionally,this review discusses these mechanisms from three perspectives:structural,synaptic,and transmitter circuits.The findings reveal that the neural circuit mechanisms of epilepsy encompass information transmission among different structures,interactions within the same structure,and the maintenance of homeostasis at the cellular,synaptic,and neurotransmitter levels.These findings offer new insights for investigating the pathophysiological mechanisms of epilepsy and enhancing its clinical diagnosis and treatment.展开更多
Optogenetics has revolutionized the field of neuroscience by enabling precise control of neural activity through light-sensitive proteins known as opsins.This review article discusses the fundamental principles of opt...Optogenetics has revolutionized the field of neuroscience by enabling precise control of neural activity through light-sensitive proteins known as opsins.This review article discusses the fundamental principles of optogenetics,including the activation of both excitatory and inhibitory opsins,as well as the development of optogenetic models that utilize recombinant viral vectors.A considerable portion of the article addresses the limitations of optogenetic tools and explores strategies to overcome these challenges.These strategies include the use of adeno-associated viruses,cell-specific promoters,modified opsins,and methodologies such as bioluminescent optogenetics.The application of viral recombinant vectors,particularly adeno-associated viruses,is emerging as a promising avenue for clinical use in delivering opsins to target cells.This trend indicates the potential for creating tools that offer greater flexibility and accuracy in opsin delivery.The adaptations of these viral vectors provide advantages in optogenetic studies by allowing for the restricted expression of opsins through cell-specific promoters and various viral serotypes.The article also examines different cellular targets for optogenetics,including neurons,astrocytes,microglia,and Schwann cells.Utilizing specific promoters for opsin expression in these cells is essential for achieving precise and efficient stimulation.Research has demonstrated that optogenetic stimulation of both neurons and glial cells-particularly the distinct phenotypes of microglia,astrocytes,and Schwann cells-can have therapeutic effects in neurological diseases.Glial cells are increasingly recognized as important targets for the treatment of these disorders.Furthermore,the article emphasizes the emerging field of bioluminescent optogenetics,which combines optogenetic principles with bioluminescent proteins to visualize and manipulate neural activity in real time.By integrating molecular genetics techniques with bioluminescence,researchers have developed methods to monitor neuronal activity efficiently and less invasively,enhancing our understanding of central nervous system function and the mechanisms of plasticity in neurological disorders beyond traditional neurobiological methods.Evidence has shown that optogenetic modulation can enhance motor axon regeneration,achieve complete sensory reinnervation,and accelerate the recovery of neuromuscular function.This approach also induces complex patterns of coordinated motor neuron activity and promotes neural reorganization.Optogenetic approaches hold immense potential for therapeutic interventions in the central nervous system.They enable precise control of neural circuits and may offer new treatments for neurological disorders,particularly spinal cord injuries,peripheral nerve injuries,and other neurodegenerative diseases.展开更多
The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regul...The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regulates diverse aspects of neural development and function. Genetic mutations within the m TOR pathway lead to severe neurodevelopmental disorders, collectively known as “mTORopathies”(Crino, 2020). Dysfunctions of m TOR, including both its hyperactivation and hypoactivation, have also been implicated in a wide spectrum of other neurodevelopmental and neurodegenerative conditions, highlighting its importance in CNS health.展开更多
Spinal cord injury results in permanent loss of neurological functions due to severance of neural networks.Transplantation of neural stem cells holds promise to repair disrupted connections.Yet,ensuring the survival a...Spinal cord injury results in permanent loss of neurological functions due to severance of neural networks.Transplantation of neural stem cells holds promise to repair disrupted connections.Yet,ensuring the survival and integration of neural stem cells into the host neural circuit remains a formidable challenge.Here,we investigated whether modifying the intrinsic properties of neural stem cells could enhance their integration post-transplantation.We focused on phosphatase and tensin homolog(PTEN),a well-characterized tumor suppressor known to critically regulate neuronal survival and axonal regeneration.By deleting Pten in mouse neural stem cells,we observed increased neurite outgrowth and enhanced resistance to neurotoxic environments in culture.Upon transplantation into injured spinal cords,Pten-deficient neural stem cells exhibited higher survival and more extensive rostrocaudal distribution.To examine the potential influence of partial PTEN suppression,rat neural stem cells were treated with short hairpin RNA targeting PTEN,and the PTEN knockdown resulted in significant improvements in neurite growth,survival,and neurosphere motility in vitro.Transplantation of sh PTEN-treated neural stem cells into the injured spinal cord also led to an increase in graft survival and migration to an extent similar to that of complete deletion.Moreover,PTEN suppression facilitated neurite elongation from NSC-derived neurons migrating from the lesion epicenter.These findings suggest that modifying intrinsic signaling pathways,such as PTEN,within neural stem cells could bolster their therapeutic efficacy,offering potential avenues for future regenerative strategies for spinal cord injury.展开更多
With the rapid development of the Artificial Intelligence of Things(AIoT),convolutional neural networks(CNNs)have demonstrated potential and remarkable performance in AIoT applications due to their excellent performan...With the rapid development of the Artificial Intelligence of Things(AIoT),convolutional neural networks(CNNs)have demonstrated potential and remarkable performance in AIoT applications due to their excellent performance in various inference tasks.However,the users have concerns about privacy leakage for the use of AI and the performance and efficiency of computing on resource-constrained IoT edge devices.Therefore,this paper proposes an efficient privacy-preserving CNN framework(i.e.,EPPA)based on the Fully Homomorphic Encryption(FHE)scheme for AIoT application scenarios.In the plaintext domain,we verify schemes with different activation structures to determine the actual activation functions applicable to the corresponding ciphertext domain.Within the encryption domain,we integrate batch normalization(BN)into the convolutional layers to simplify the computation process.For nonlinear activation functions,we use composite polynomials for approximate calculation.Regarding the noise accumulation caused by homomorphic multiplication operations,we realize the refreshment of ciphertext noise through minimal“decryption-encryption”interactions,instead of adopting bootstrapping operations.Additionally,in practical implementation,we convert three-dimensional convolution into two-dimensional convolution to reduce the amount of computation in the encryption domain.Finally,we conduct extensive experiments on four IoT datasets,different CNN architectures,and two platforms with different resource configurations to evaluate the performance of EPPA in detail.展开更多
Contrary to the adult central nervous system,the peripheral nervous system has an intrinsic ability to regenerate that relies on the expression of regenerationassociated genes,such as some kinesin family members.Kines...Contrary to the adult central nervous system,the peripheral nervous system has an intrinsic ability to regenerate that relies on the expression of regenerationassociated genes,such as some kinesin family members.Kinesins contribute to nerve regeneration through the transport of specific cargo,such as proteins and membrane components,from the cell body towards the axon periphery.We show here that KIF4A,associated with neurodevelopmental disorders and previously believed to be only expressed during development,is also expressed in the adult vertebrate nervous system and up-regulated in injured peripheral nervous system cells.KIF4A is detected both in the cell bodies and regrowing axons of injured neurons,consistent with its function as an axonal transporter of cargoes such asβ1-integrin and L1CAM.Our study further demonstrates that KIF4A levels are greatly increased in Schwann cells from injured distal nerve stumps,particularly at a time when they are reprogrammed into an essential proliferative repair phenotype.Moreover,Kif4a m RNA levels were approximately~6-fold higher in proliferative cultured Schwann cells compared with non-proliferative ones.A hypothesized function for Kif4a in Schwann cell proliferation was further confirmed by Kif4a knockdown,as this significantly reduced Schwann cell proliferation in vitro.Our findings show that KIF4A is expressed in adult vertebrate nervous systems and is up-regulated following peripheral injury.The timing of KIF4A up-regulation,its location during regeneration,and its proliferative role,all suggest a dual role for this protein in neuroregeneration that is worth exploring in the future.展开更多
Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after inju...Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.展开更多
Neural stem cells(NSCs)have the potential for self-renewal and multidirectional differentiation,and their transplantation has achieved good efficacy in a variety of diseases.However,only 1%-10%of transplanted NSCs sur...Neural stem cells(NSCs)have the potential for self-renewal and multidirectional differentiation,and their transplantation has achieved good efficacy in a variety of diseases.However,only 1%-10%of transplanted NSCs survive in the ischemic and hypoxic microenvironment of posthemorrhagic hydrocephalus.^(Sox2)is an important factor for NSCs to maintain proliferation.Therefore,^(Sox2)-overexpressing NSCs(NSC^(Sox2))may be more successful in improving neurological dysfunction after posthemorrhagic hydrocephalus.In this study,human NSC^(Sox2)was transplanted into a posthemorrhagic hydrocephalus mouse model,and retinoic acid was administered to further promote NSC differentiation.The results showed that NSC^(Sox2)attenuated the ventricular enlargement caused by posthemorrhagic hydrocephalus and improved neurological function.NSC^(Sox2)also promoted nerve regeneration,inhibited neuroinflammation and promoted M2 polarization(anti-inflammatory phenotype),thereby reducing cerebrospinal fluid secretion in choroid plexus.These findings suggest that NSC^(Sox2)rescued ventricular enlargement and neurological dysfunction induced by posthemorrhagic hydrocephalus through neural regeneration and modulation of inflammation.展开更多
Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using d...Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested.展开更多
Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic i...Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic injuries,and neurological diseases.Neural machine interface technology establishes direct connections with the brain or peripheral nervous system to restore impaired motor,sensory,and cognitive functions,significantly improving patients'quality of life.This review analyzes the chronological development and integration of various neural machine interface technologies,including regenerative peripheral nerve interfaces,targeted muscle and sensory reinnervation,agonist–antagonist myoneural interfaces,and brain–machine interfaces.Recent advancements in flexible electronics and bioengineering have led to the development of more biocompatible and highresolution electrodes,which enhance the performance and longevity of neural machine interface technology.However,significant challenges remain,such as signal interference,fibrous tissue encapsulation,and the need for precise anatomical localization and reconstruction.The integration of advanced signal processing algorithms,particularly those utilizing artificial intelligence and machine learning,has the potential to improve the accuracy and reliability of neural signal interpretation,which will make neural machine interface technologies more intuitive and effective.These technologies have broad,impactful clinical applications,ranging from motor restoration and sensory feedback in prosthetics to neurological disorder treatment and neurorehabilitation.This review suggests that multidisciplinary collaboration will play a critical role in advancing neural machine interface technologies by combining insights from biomedical engineering,clinical surgery,and neuroengineering to develop more sophisticated and reliable interfaces.By addressing existing limitations and exploring new technological frontiers,neural machine interface technologies have the potential to revolutionize neuroprosthetics and neurorehabilitation,promising enhanced mobility,independence,and quality of life for individuals with neurological impairments.By leveraging detailed anatomical knowledge and integrating cutting-edge neuroengineering principles,researchers and clinicians can push the boundaries of what is possible and create increasingly sophisticated and long-lasting prosthetic devices that provide sustained benefits for users.展开更多
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
Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge- nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats w...Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge- nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into five groups： （1） sham operation （control）, （2） cerebral palsy model alone or with （3） phosphate-buffered saline, （4） vascular en- dothelial growth factor 165 ＋ neural stem cells, or （5） neural stem cells alone. The cerebral palsy model was established by ligating the left common carotid artery followed by exposure to hypox- ia. Phosphate-buffered saline, vascular endothelial growth factor ＋ neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. After transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas- cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for finding water and the finding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. These findings indicate that the transplantation of vascu- lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deficits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.展开更多
Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)...Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system diseases.In this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism.Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage.Additionally,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory microenvironment.RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier integrity.Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects.In summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.展开更多
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ...Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury.展开更多
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li...Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.展开更多
基金the National Natural Scientific Foundation of China(82071994,82202249)Tianjin Health High Level Talent Selection and Training Project(TJSQNYXXR-D2-143)+4 种基金Natural Scientific Foundation of Tianjin(21CYBJC01580,21JCQNJC01480)Tianjin Health Research Project(TJWJ2023QN031,TJWJ2023XK012)Tianjin Health Science and technology project(Specific projects of key disciplines)(TJWJ2022XK019)Tianjin Key Medical Discipline(Specialty)Construction Project(TJYXZDXK-041A)Tianjin Natural Science Foundation(21JCYBJC01290).
文摘Hepatic encephalopathy(HE)is a neurological condition that occurs as a complication of liver dysfunction that involves sensorimotor symptoms in addition to cognitive and behavioral changes,particularly in cases of severe liver disease or cirrhosis.Previous studies have reported spatially distributed structural and functional abnormalities related to HE,but the exact relationship between the structural and functional alterations with respect to disease progression remains unclear.In this study,we performed surface-based cortical thickness comparisons and functional connectivity(FC)analyses between three cross-sectional groups:healthy controls(HC,N¼51),patients with minimal hepatic en-cephalopathy(MHE,N¼50),patients with overt hepatic encephalopathy(OHE,N¼51).In addition to the distributed cortical thinning that is extensively thought to be associated with cognitive decline in HE,we found significant cortical thickening in the left para-hippocampal gyrus cortex in the OHE group(p<0.001,p¼0.009)as compared to the HC and MHE group respectively,which is further corroborated by the significant correlation between the cortical thickness and digit symbol test(DST)scores.Furthermore,the decreased FC between the right postcentral gyrus and several sensory regions(bilateral somatosensory and visual cortices)was found to be significant in MHE patients as compared to the HC group.Our results revealed cross-sectional structural and functional variations concerning disease progression across different subsystems(e.g.,visual,motor and sensory),providing evidence that can potentially explain the mechanisms underlying the sensorimotor and cognitive deficits related to HE.
基金supported by the National Key Research and Development Program of China,No.2023YFC3603705(to DX)the National Natural Science Foundation of China,No.82302866(to YZ).
文摘After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions.
基金supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (2020M3E5D9079764, RS-2024-00408736)(to KS)supported by Korea Drug Development Fund funded by Ministry of Science and ICT,Ministry of Trade,Industry,and Energy,and Ministry of Health and Welfare (RS-2024-00335752)(to KS)。
文摘The hippocampus is part of the brain limbic system and plays an important role in learning and memory.Moreover,its ability to form,consolidate,and retrieve different types of memories makes it a central component in the cognitive functions necessary for everyday life.Understanding the role of the hippocampus helps comprehend how memories are created,stored,and recalled and sheds light on the impact of hippocampal damage in conditions such as Alzheimer’s disease and other forms of dementia.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2021R1A6A1A10044950).
文摘The thermal conductivity of nanofluids is an important property that influences the heat transfer capabilities of nanofluids.Researchers rely on experimental investigations to explore nanofluid properties,as it is a necessary step before their practical application.As these investigations are time and resource-consuming undertakings,an effective prediction model can significantly improve the efficiency of research operations.In this work,an Artificial Neural Network(ANN)model is developed to predict the thermal conductivity of metal oxide water-based nanofluid.For this,a comprehensive set of 691 data points was collected from the literature.This dataset is split into training(70%),validation(15%),and testing(15%)and used to train the ANN model.The developed model is a backpropagation artificial neural network with a 4–12–1 architecture.The performance of the developed model shows high accuracy with R values above 0.90 and rapid convergence.It shows that the developed ANN model accurately predicts the thermal conductivity of nanofluids.
基金supported by NIH grants,Nos.R01NS125074,R01AG083164,R01NS107365,and R21NS127177(to YL),1F31NS129204-01A1(to KW)and Albert Ryan Fellowship(to KW).
文摘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.
基金supported by Basic Research Programs of Science and Technology Commission Foundation of Shanxi Province,No.20210302123486(to WJ).
文摘Epilepsy,a common neurological disorder,is characterized by recurrent seizures that can lead to cognitive,psychological,and neurobiological consequences.The pathogenesis of epilepsy involves neuronal dysfunction at the molecular,cellular,and neural circuit levels.Abnormal molecular signaling pathways or dysfunction of specific cell types can lead to epilepsy by disrupting the normal functioning of neural circuits.The continuous emergence of new technologies and the rapid advancement of existing ones have facilitated the discovery and comprehensive understanding of the neural circuit mechanisms underlying epilepsy.Therefore,this review aims to investigate the current understanding of the neural circuit mechanisms in epilepsy based on various technologies,including electroencephalography,magnetic resonance imaging,optogenetics,chemogenetics,deep brain stimulation,and brain-computer interfaces.Additionally,this review discusses these mechanisms from three perspectives:structural,synaptic,and transmitter circuits.The findings reveal that the neural circuit mechanisms of epilepsy encompass information transmission among different structures,interactions within the same structure,and the maintenance of homeostasis at the cellular,synaptic,and neurotransmitter levels.These findings offer new insights for investigating the pathophysiological mechanisms of epilepsy and enhancing its clinical diagnosis and treatment.
基金supported by a grant from the Russian Science Foundation,No.23-75-10041(to MY)。
文摘Optogenetics has revolutionized the field of neuroscience by enabling precise control of neural activity through light-sensitive proteins known as opsins.This review article discusses the fundamental principles of optogenetics,including the activation of both excitatory and inhibitory opsins,as well as the development of optogenetic models that utilize recombinant viral vectors.A considerable portion of the article addresses the limitations of optogenetic tools and explores strategies to overcome these challenges.These strategies include the use of adeno-associated viruses,cell-specific promoters,modified opsins,and methodologies such as bioluminescent optogenetics.The application of viral recombinant vectors,particularly adeno-associated viruses,is emerging as a promising avenue for clinical use in delivering opsins to target cells.This trend indicates the potential for creating tools that offer greater flexibility and accuracy in opsin delivery.The adaptations of these viral vectors provide advantages in optogenetic studies by allowing for the restricted expression of opsins through cell-specific promoters and various viral serotypes.The article also examines different cellular targets for optogenetics,including neurons,astrocytes,microglia,and Schwann cells.Utilizing specific promoters for opsin expression in these cells is essential for achieving precise and efficient stimulation.Research has demonstrated that optogenetic stimulation of both neurons and glial cells-particularly the distinct phenotypes of microglia,astrocytes,and Schwann cells-can have therapeutic effects in neurological diseases.Glial cells are increasingly recognized as important targets for the treatment of these disorders.Furthermore,the article emphasizes the emerging field of bioluminescent optogenetics,which combines optogenetic principles with bioluminescent proteins to visualize and manipulate neural activity in real time.By integrating molecular genetics techniques with bioluminescence,researchers have developed methods to monitor neuronal activity efficiently and less invasively,enhancing our understanding of central nervous system function and the mechanisms of plasticity in neurological disorders beyond traditional neurobiological methods.Evidence has shown that optogenetic modulation can enhance motor axon regeneration,achieve complete sensory reinnervation,and accelerate the recovery of neuromuscular function.This approach also induces complex patterns of coordinated motor neuron activity and promotes neural reorganization.Optogenetic approaches hold immense potential for therapeutic interventions in the central nervous system.They enable precise control of neural circuits and may offer new treatments for neurological disorders,particularly spinal cord injuries,peripheral nerve injuries,and other neurodegenerative diseases.
基金supported by grants from Simons Foundation (SFARI 479754),CIHR (PJT-180565)the Scottish Rite Charitable Foundation of Canada (to YL)funding from the Canada Research Chairs program。
文摘The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regulates diverse aspects of neural development and function. Genetic mutations within the m TOR pathway lead to severe neurodevelopmental disorders, collectively known as “mTORopathies”(Crino, 2020). Dysfunctions of m TOR, including both its hyperactivation and hypoactivation, have also been implicated in a wide spectrum of other neurodevelopmental and neurodegenerative conditions, highlighting its importance in CNS health.
基金supported by the National Research Foundation of Korea,Nos.2021R1A2C2006110,2021M3E5D9021364,2019R1A5A2026045(to BGK)the Korea Initiative for Fostering University of Research and Innovation(KIURI)Program of the NRF funded by the MSIT(to HK),No.NRF2021M3H1A104892211(to HSK)。
文摘Spinal cord injury results in permanent loss of neurological functions due to severance of neural networks.Transplantation of neural stem cells holds promise to repair disrupted connections.Yet,ensuring the survival and integration of neural stem cells into the host neural circuit remains a formidable challenge.Here,we investigated whether modifying the intrinsic properties of neural stem cells could enhance their integration post-transplantation.We focused on phosphatase and tensin homolog(PTEN),a well-characterized tumor suppressor known to critically regulate neuronal survival and axonal regeneration.By deleting Pten in mouse neural stem cells,we observed increased neurite outgrowth and enhanced resistance to neurotoxic environments in culture.Upon transplantation into injured spinal cords,Pten-deficient neural stem cells exhibited higher survival and more extensive rostrocaudal distribution.To examine the potential influence of partial PTEN suppression,rat neural stem cells were treated with short hairpin RNA targeting PTEN,and the PTEN knockdown resulted in significant improvements in neurite growth,survival,and neurosphere motility in vitro.Transplantation of sh PTEN-treated neural stem cells into the injured spinal cord also led to an increase in graft survival and migration to an extent similar to that of complete deletion.Moreover,PTEN suppression facilitated neurite elongation from NSC-derived neurons migrating from the lesion epicenter.These findings suggest that modifying intrinsic signaling pathways,such as PTEN,within neural stem cells could bolster their therapeutic efficacy,offering potential avenues for future regenerative strategies for spinal cord injury.
基金supported by the Natural Science Foundation of China No.62362008the Major Scientific and Technological Special Project of Guizhou Province([2024]014).
文摘With the rapid development of the Artificial Intelligence of Things(AIoT),convolutional neural networks(CNNs)have demonstrated potential and remarkable performance in AIoT applications due to their excellent performance in various inference tasks.However,the users have concerns about privacy leakage for the use of AI and the performance and efficiency of computing on resource-constrained IoT edge devices.Therefore,this paper proposes an efficient privacy-preserving CNN framework(i.e.,EPPA)based on the Fully Homomorphic Encryption(FHE)scheme for AIoT application scenarios.In the plaintext domain,we verify schemes with different activation structures to determine the actual activation functions applicable to the corresponding ciphertext domain.Within the encryption domain,we integrate batch normalization(BN)into the convolutional layers to simplify the computation process.For nonlinear activation functions,we use composite polynomials for approximate calculation.Regarding the noise accumulation caused by homomorphic multiplication operations,we realize the refreshment of ciphertext noise through minimal“decryption-encryption”interactions,instead of adopting bootstrapping operations.Additionally,in practical implementation,we convert three-dimensional convolution into two-dimensional convolution to reduce the amount of computation in the encryption domain.Finally,we conduct extensive experiments on four IoT datasets,different CNN architectures,and two platforms with different resource configurations to evaluate the performance of EPPA in detail.
基金supported by the Portuguese Foundation for Science and Technology(FCT),Centro 2020 and Portugol2020 and the EU FEDER program,via the project GoBack to SIV(PTDC/CVT-CVT/32261/2017,CENTRO-01-0145-FEDER-032261)the doctoral grants of PDC(SFRH/BD/139974/2018)and BMS(2020.06525.BD and DOI 10.54499/2020.06525.BD)+5 种基金the post-doctoral grant to JPF(SFRH/BPD/113359/2015-program-contract described in paragraphs 4,5,6 of art.23 of Law no.100157/2016,of August 29,as amended by Law no.57/2017 of July 2019),the project PTDC/MED-NEU/1677/2021 to JBRthe Institute of Biomedicine iBiMED(UIDB/04501/2020 and DOI 10.54499/UIDB/04501/2020,UIDP/04501/2020 and DOI 10.54499/UIDP/04501/2020)its LiM Bioimaging Facility-a PPBI node(POCI-01-0145-FEDER-022122)supported by the Research Commission of the Medical Faculty of the Heinrich-Heine-University(HHU)Düsseldorf,of the Biologisch-Medizinisches Forschungszentrum(BMFZ)of HHUfinanced by the Spanish"Plan Nacional de Investigacion Cientifica,Desarrollo e Innovacion Tecnologica,Ministerio de Economia y Competitividad(Instituto de Salud CarlosⅢ)",co-financed by the European Union(FEDER program),(grant FIS P/20/00318 and FIS P23/00337 to VC)grant CPP2021-009070 to VC by the"Proyectos de colaboracion publico-privada,Plan de Investigacion Cientifica,Tecnica y de inovacion 2021-2023,Ministerio de Ciencia e Innovacion,Union Europea,Agencia Estatal de Investigacion,Espana"。
文摘Contrary to the adult central nervous system,the peripheral nervous system has an intrinsic ability to regenerate that relies on the expression of regenerationassociated genes,such as some kinesin family members.Kinesins contribute to nerve regeneration through the transport of specific cargo,such as proteins and membrane components,from the cell body towards the axon periphery.We show here that KIF4A,associated with neurodevelopmental disorders and previously believed to be only expressed during development,is also expressed in the adult vertebrate nervous system and up-regulated in injured peripheral nervous system cells.KIF4A is detected both in the cell bodies and regrowing axons of injured neurons,consistent with its function as an axonal transporter of cargoes such asβ1-integrin and L1CAM.Our study further demonstrates that KIF4A levels are greatly increased in Schwann cells from injured distal nerve stumps,particularly at a time when they are reprogrammed into an essential proliferative repair phenotype.Moreover,Kif4a m RNA levels were approximately~6-fold higher in proliferative cultured Schwann cells compared with non-proliferative ones.A hypothesized function for Kif4a in Schwann cell proliferation was further confirmed by Kif4a knockdown,as this significantly reduced Schwann cell proliferation in vitro.Our findings show that KIF4A is expressed in adult vertebrate nervous systems and is up-regulated following peripheral injury.The timing of KIF4A up-regulation,its location during regeneration,and its proliferative role,all suggest a dual role for this protein in neuroregeneration that is worth exploring in the future.
文摘Exogenous neural stem cell transplantation has become one of the most promising treatment methods for chronic stroke.Recent studies have shown that most ischemia-reperfusion model rats recover spontaneously after injury,which limits the ability to observe long-term behavioral recovery.Here,we used a severe stroke rat model with 150 minutes of ischemia,which produced severe behavioral deficiencies that persisted at 12 weeks,to study the therapeutic effect of neural stem cells on neural restoration in chronic stroke.Our study showed that stroke model rats treated with human neural stem cells had long-term sustained recovery of motor function,reduced infarction volume,long-term human neural stem cell survival,and improved local inflammatory environment and angiogenesis.We also demonstrated that transplanted human neural stem cells differentiated into mature neurons in vivo,formed stable functional synaptic connections with host neurons,and exhibited the electrophysiological properties of functional mature neurons,indicating that they replaced the damaged host neurons.The findings showed that human fetal-derived neural stem cells had long-term effects for neurological recovery in a model of severe stroke,which suggests that human neural stem cells-based therapy may be effective for repairing damaged neural circuits in stroke patients.
基金supported by the National Natural Science Foundation of China,Nos.82473334(to LZ),82401629(to XL)the Major Scientific and Technological Achievements Transformation Project of Ningxia Hui Autonomous Region,No.2022CJE09013(to LZ)+4 种基金Mianyang Science and Technology Bureau(Mianyang Science and Technology Program),No.2023ZYDF097(to LZ)NHC Key Laboratory of Nuclear Technology Medical Transformation(Mianyang Central Hospital),No.2023HYX001(to LZ)Spinal Cord Diseases Clinical Medical Center of Yunnan Province,No.2024JSKFKT-16(to BG)the Natural Science Foundation of Sichuan Province,No.2024NSFSC1646(to XL)the China Postdoctoral Science Foundation,Nos.GZC20231811(to XL),2024T170601(to XL)and 2024M76228(to XL).
文摘Neural stem cells(NSCs)have the potential for self-renewal and multidirectional differentiation,and their transplantation has achieved good efficacy in a variety of diseases.However,only 1%-10%of transplanted NSCs survive in the ischemic and hypoxic microenvironment of posthemorrhagic hydrocephalus.^(Sox2)is an important factor for NSCs to maintain proliferation.Therefore,^(Sox2)-overexpressing NSCs(NSC^(Sox2))may be more successful in improving neurological dysfunction after posthemorrhagic hydrocephalus.In this study,human NSC^(Sox2)was transplanted into a posthemorrhagic hydrocephalus mouse model,and retinoic acid was administered to further promote NSC differentiation.The results showed that NSC^(Sox2)attenuated the ventricular enlargement caused by posthemorrhagic hydrocephalus and improved neurological function.NSC^(Sox2)also promoted nerve regeneration,inhibited neuroinflammation and promoted M2 polarization(anti-inflammatory phenotype),thereby reducing cerebrospinal fluid secretion in choroid plexus.These findings suggest that NSC^(Sox2)rescued ventricular enlargement and neurological dysfunction induced by posthemorrhagic hydrocephalus through neural regeneration and modulation of inflammation.
基金The work described in this paper was fully supported by a grant from Hong Kong Metropolitan University(RIF/2021/05).
文摘Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested.
基金supported in part by the National Natural Science Foundation of China,Nos.81927804(to GL),82260456(to LY),U21A20479(to LY)Science and Technology Planning Project of Shenzhen,No.JCYJ20230807140559047(to LY)+3 种基金Key-Area Research and Development Program of Guangdong Province,No.2020B0909020004(to GL)Guangdong Basic and Applied Research Foundation,No.2023A1515011478(to LY)the Science and Technology Program of Guangdong Province,No.2022A0505090007(to GL)Ministry of Science and Technology,Shenzhen,No.QN2022032013L(to LY)。
文摘Neural machine interface technology is a pioneering approach that aims to address the complex challenges of neurological dysfunctions and disabilities resulting from conditions such as congenital disorders,traumatic injuries,and neurological diseases.Neural machine interface technology establishes direct connections with the brain or peripheral nervous system to restore impaired motor,sensory,and cognitive functions,significantly improving patients'quality of life.This review analyzes the chronological development and integration of various neural machine interface technologies,including regenerative peripheral nerve interfaces,targeted muscle and sensory reinnervation,agonist–antagonist myoneural interfaces,and brain–machine interfaces.Recent advancements in flexible electronics and bioengineering have led to the development of more biocompatible and highresolution electrodes,which enhance the performance and longevity of neural machine interface technology.However,significant challenges remain,such as signal interference,fibrous tissue encapsulation,and the need for precise anatomical localization and reconstruction.The integration of advanced signal processing algorithms,particularly those utilizing artificial intelligence and machine learning,has the potential to improve the accuracy and reliability of neural signal interpretation,which will make neural machine interface technologies more intuitive and effective.These technologies have broad,impactful clinical applications,ranging from motor restoration and sensory feedback in prosthetics to neurological disorder treatment and neurorehabilitation.This review suggests that multidisciplinary collaboration will play a critical role in advancing neural machine interface technologies by combining insights from biomedical engineering,clinical surgery,and neuroengineering to develop more sophisticated and reliable interfaces.By addressing existing limitations and exploring new technological frontiers,neural machine interface technologies have the potential to revolutionize neuroprosthetics and neurorehabilitation,promising enhanced mobility,independence,and quality of life for individuals with neurological impairments.By leveraging detailed anatomical knowledge and integrating cutting-edge neuroengineering principles,researchers and clinicians can push the boundaries of what is possible and create increasingly sophisticated and long-lasting prosthetic devices that provide sustained benefits for users.
基金supported by the National Natural Science Foundation of China,No.81571211(to FL)the Natural Science Foundation of Shanghai,No.22ZR1476800(to CH)。
文摘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.
基金supported by grants from the National Natural Science Foundation of China,No.81070523,81270728
文摘Neural stem cells are characterized by the ability to differentiate and stably express exogenous ge- nes. Vascular endothelial growth factor plays a role in protecting local blood vessels and neurons of newborn rats with hypoxic-ischemic encephalopathy. Transplantation of vascular endothelial growth factor-transfected neural stem cells may be neuroprotective in rats with cerebral palsy. In this study, 7-day-old Sprague-Dawley rats were divided into five groups： （1） sham operation （control）, （2） cerebral palsy model alone or with （3） phosphate-buffered saline, （4） vascular en- dothelial growth factor 165 ＋ neural stem cells, or （5） neural stem cells alone. The cerebral palsy model was established by ligating the left common carotid artery followed by exposure to hypox- ia. Phosphate-buffered saline, vascular endothelial growth factor ＋ neural stem cells, and neural stem cells alone were administered into the sensorimotor cortex using the stereotaxic instrument and microsyringe. After transplantation, the radial-arm water maze test and holding test were performed. Immunohistochemistry for vascular endothelial growth factor and histology using hematoxylin-eosin were performed on cerebral cortex. Results revealed that the number of vas- cular endothelial growth factor-positive cells in cerebral palsy rats transplanted with vascular endothelial growth factor-transfected neural stem cells was increased, the time for finding water and the finding repetitions were reduced, the holding time was prolonged, and the degree of cell degeneration or necrosis was reduced. These findings indicate that the transplantation of vascu- lar endothelial growth factor-transfected neural stem cells alleviates brain damage and cognitive deficits, and is neuroprotective in neonatal rats with hypoxia ischemic-mediated cerebral palsy.
基金supported by the National Natural Science Foundation of China,No.8227050826(to PL)Tianjin Science and Technology Bureau Foundation,No.20201194(to PL)Tianjin Graduate Research and Innovation Project,No.2022BKY174(to CW).
文摘Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor prognosis.Human-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system diseases.In this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying mechanism.Our results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral hemorrhage.Additionally,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory microenvironment.RNA sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier integrity.Treatment with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these effects.In summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.
基金supported by the National Natural Science Foundation of China,Nos.82271397(to MG),82001293(to MG),82171355(to RX),81971295(to RX),and 81671189(to RX)。
文摘Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury.
基金supported by the National Key R&D Program of China,No.2019YFA0110300(to ZG)the National Natural Science Foundation of China,Nos.81773302(to YF),32070862(to ZG).
文摘Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.
