Microglia are one of the three glial cell populations in the central nervous system(CNS),along with astrocytes and oligodendrocytes.While microglia are unique among brain cells due to their hematologic origin and perf...Microglia are one of the three glial cell populations in the central nervous system(CNS),along with astrocytes and oligodendrocytes.While microglia are unique among brain cells due to their hematologic origin and perform immune functions similar to peripheral macrophages,they are not simply macrophages of the CNS.展开更多
AIM: To characterize and compare our current series of patients to prior reports in order to identify any changes in the incidence of neurological injury related to hunting accidents in Rochester, New York.METHODS: Al...AIM: To characterize and compare our current series of patients to prior reports in order to identify any changes in the incidence of neurological injury related to hunting accidents in Rochester, New York.METHODS: All tree stand-related injuries referred to our regional trauma center from September 2003 through November 2011 were reviewed. Information was obtained from the hospital's trauma registry and medical records were retrospectively reviewed for data pertaining to the injuries.RESULTS: Fifty-four patients were identified. Ninetysix percent of patients were male with a mean age of 47.9 years(range 15-69). The mean Injury Severity Score was 12.53 ± 1.17(range 2-34). The average height of fall was 18.2 feet(range 4-40 feet). All patients fell to the ground with the exception of one who landed on rocks, and many hit the tree or branches on the way down. A reason for the fall was documented in only 13 patients, and included tree stand construction(3), loss of balance(3), falling asleep(3), structural failure(2), safety harness breakage(3) or lightheadedness(1). The most common injuries were spinal fractures(54%), most commonly in the cervical spine(69%), followed by the thoracic(38%) and lumbar(21%) spine. Eight patients required operative repair. Head injuries occurred in 22%. Other systemic injuries include rib/clavicular fractures(47%), pelvic fractures(11%), solid organ injury(23%), and pneumothorax or hemothorax(19%). No patient deaths were reported. The average hospital length of stay was 6.56 ± 1.07 d. Most patients were discharged home without(72%) or with(11%) services and 17% required rehabilitation. CONCLUSION: Falls from hunting tree stands are still common, with a high rate of neurological injury. Compared to a decade ago we have made no progress in preventing these neurological injuries, despite an increase in safety advances. Neurosurgeons must continue to advocate for increased safety awareness and participate in leadership roles to improve outcomes for hunters.展开更多
To investigate the effects of different degrees of hemodilution on neurological injury and amino acid content in different brain areas after deep hypothermic circulatory arrest (DHCA).Methods Forty-eight male adult SD...To investigate the effects of different degrees of hemodilution on neurological injury and amino acid content in different brain areas after deep hypothermic circulatory arrest (DHCA).Methods Forty-eight male adult SD rats weighing 400～450 g were randomly divided into 4 groups (n=12 each):group Ⅰ Hct 10%(H1);group Ⅱ Hct 20% (H2);group Ⅲ Hct 30%(H3) and control group (C).All animals except those in control group underwent DHCA at 18℃ for 90 min (includinhg cooling and rewarming) under general anesthesia with fentanyl,ketamine and droperidol.Different degrees of hemodilution were accomplised by changing the composition and volume of priming solution used in cardiopulmonary bypass (CPB).Hct was determined before,at the initiation of CPB and beginning of rewarming.PaO2,pH and blood lactate of arterial blood and SO2 of venous blood from internal jugular vein (SjvO2) were determined at the beginning and end of cooling and rewarming.The animals were killed and brains removed after recovery of circulatory function for the count of injured neurons and detemination of glutamate (Glu),aspartate (Asp),glycine (Gly),γ-aminobutyric acid (GABA) and taurine (Tau) contents in cortex,hippocampus and thalamus.Results The number of injured neurons in hippocampus and parietal cortex were significantly smaller in Hct 30% group than in the other two groups (P<0.05).The contents of the five amino acids in hippocampus and parietal cortex were all increased after DHCA.The Glu,Asp and Gly contents in hippocampus and parietal cortex were significantly lower in Hct 30% group than in the other 2 groups (P<0.05).There was no significant difference in GABA and Tau contents among the 3 groups.Conclusion Hemodilution at Hct 30% attenuates the neuronal injury after DHCA.The inhibition of the release of the excitatory amino acids in the brain may be involved in the mechanism of neuronal protection.13 refs,1 fig,3 tabs.展开更多
Acquired neurological injuries initiate a pathological cascade of secondary injury processes,including inflammation,which continue for days to weeks following injury.Injury-induced neuroinflammation acts as a host def...Acquired neurological injuries initiate a pathological cascade of secondary injury processes,including inflammation,which continue for days to weeks following injury.Injury-induced neuroinflammation acts as a host defense mechanism contributing to the neutralization of the insult(removing offending factors)and restoring structure and function of the brain(establish homeostasis).The timing of these protective functions of the immune response is vital,since chronic展开更多
BACKGROUND Elevated levels of cardiac troponin and abnormal electrocardiogram changes are the primary basis for clinical diagnosis of acute coronary syndrome(ACS).Troponin levels in ACS patients can often be more than...BACKGROUND Elevated levels of cardiac troponin and abnormal electrocardiogram changes are the primary basis for clinical diagnosis of acute coronary syndrome(ACS).Troponin levels in ACS patients can often be more than 50 times the upper reference limit.Some patients with subarachnoid hemorrhage(SAH)also show electrocardiogram abnormalities,myocardial damage,and elevated cardiac biomarkers.Unlike ACS patients,patients with SAH only have a slight increase in troponin,and the use of anticoagulants or antiplatelet drugs is prohibited.Because of the opposite treatment modalities,it is essential for clinicians to distinguish between SAH and ACS.CASE SUMMARY A 56-year-old female patient was admitted to the emergency department at night with a sudden onset of severe back pain.The final diagnosis was intraspinal hematoma in the thoracic spine.We performed an emergency thoracic spinal canal hematoma evacuation procedure with the assistance of a microscope.Intraoperatively,diffuse hematoma formation was found in the T7-T10 spinal canal,and no obvious spinal vascular malformation changes were observed.Postoperative head and spinal magnetic resonance imaging(MRI)showed a small amount of SAH in the skull,no obvious abnormalities in the cervical and thoracic spinal canals,and no abnormal signals in the lumbar spinal canal.Thoracoab-dominal aorta computed tomography angiography showed no vascular malfor-mation.Postoperative motor system examination showed Medical Research Council Scale grade 1/5 strength in both lower extremities,and the patient experienced decreased sensation below the T12 rib margin and reported a Visual Analog Scale score of 3.CONCLUSION Extremely elevated troponin levels(more than 50 times the normal range)are not unique to coronary artery disease.SAH can also result in extremely high troponin levels,and antiplatelet drugs are contraindicated in such cases.Emergency MRI can help in the early differential diagnosis,as a misdiagnosis of ACS can lead to catastrophic neurological damage in patients with spontaneous spinal SAH.展开更多
Studies have shown that repetitive transcra nial magnetic stimulation(rTMS)can enhance synaptic plasticity and improve neurological dysfunction.Howeve r,the mechanism through which rTMS can improve moderate traumatic ...Studies have shown that repetitive transcra nial magnetic stimulation(rTMS)can enhance synaptic plasticity and improve neurological dysfunction.Howeve r,the mechanism through which rTMS can improve moderate traumatic brain injury remains poorly understood.In this study,we established rat models of moderate traumatic brain injury using Feeney's weight-dropping method and treated them using rTMS.To help determine the mechanism of action,we measured levels of seve ral impo rtant brain activity-related proteins and their mRNA.On the injured side of the brain,we found that rTMS increased the protein levels and mRNA expression of brain-derived neurotrophic factor,tropomyosin receptor kinase B,N-methyl-D-aspartic acid receptor 1,and phosphorylated cAMP response element binding protein,which are closely associated with the occurrence of long-term potentiation.rTMS also partially reve rsed the loss of synaptophysin after injury and promoted the remodeling of synaptic ultrastructure.These findings suggest that upregulation of synaptic plasticity-related protein expression is the mechanism through which rTMS promotes neurological function recovery after moderate traumatic brain injury.展开更多
Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotectiv...Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotective effects of erythropoietin on spinal cord injury has not been examined.In this study,we established rat models of spinal cord injury by modified Allen’s method and intraperitoneally administered 1000 and 5000 IU/kg erythropoietin once a week for 2 successive weeks.Both low and high doses of erythropoietin promoted recovery of hindlimb function,and the high dose of erythropoietin led to better outcome.High dose of erythropoietin exhibited a stronger suppressive effect on ferroptosis relative to the low dose of erythropoietin.The effects of erythropoietin on inhibiting ferroptosis-related protein expression and restoring mitochondrial morphology were similar to those of Fer-1(a ferroptosis suppressor),and the effects of erythropoietin were largely diminished by RSL3(ferroptosis activator).In vitro experiments showed that erythropoietin inhibited RSL3-induced ferroptosis in PC12 cells and increased the expression of xCT and Gpx4.This suggests that xCT and Gpx4 are involved in the neuroprotective effects of erythropoietin on spinal cord injury.Our findings reveal the underlying anti-ferroptosis role of erythropoietin and provide a potential therapeutic strategy for treating spinal cord injury.展开更多
Chronic compressive spinal cord injury in compressive cervical myelopathy conditions can lead to rapid neurological deterioration in the early phase,followed by partial self-recovery,and ultimately an equilibrium stat...Chronic compressive spinal cord injury in compressive cervical myelopathy conditions can lead to rapid neurological deterioration in the early phase,followed by partial self-recovery,and ultimately an equilibrium state of neurological dysfunction.Ferroptosis is a crucial pathological process in many neurodegenerative diseases;however,its role in chro nic compressive spinal cord injury remains unclear.In this study,we established a chronic compressive spinal cord injury rat model,which displayed its most severe behavioral and electrophysiological dysfunction at 4 wee ks and partial recovery at 8 weeks after compression.Bulk RNA sequencing data identified enriched functional pathways,including ferroptosis,presynapse,and postsynaptic membrane activity at both 4 and 8 wee ks following chro nic compressive spinal co rd injury.Tra nsmission electron microscopy and malondialdehyde quantification assay confirmed that ferroptosis activity peaked at 4 weeks and was attenuated at 8 weeks after chronic compression.Ferro ptosis activity was negatively correlated with behavioral score.Immunofluorescence,quantitative polymerase chain reaction,and western blotting showed that expression of the anti-ferroptosis molecules,glutathione peroxidase 4(GPX4) and MAF BZIP transcription factor G(MafG),in neuro ns was suppressed at 4 weeks and upregulated at 8 weeks following spinal co rd compression.There was a positive correlation between the expression of these two molecules,suggesting that they may work together to contribute to functional recovery following chronic compressive spinal cord injury.In conclusion,our study determined the genome-wide expression profile and fe rroptosis activity of a consistently compressed spinal cord at different time points.The results showed that anti-fe rroptosis genes,specifically GPX4 and MafG,may be involved in spontaneous neurological recovery at 8 weeks of chronic compressive spinal cord injury.These findings contribute to a better understanding of the mechanisms underlying chronic compressive spinal cord injury and may help identify new therapeutic targets for compressive cervical myelopathy.展开更多
Objective To investigate the effects of propofol and sevoflurane on neurological recovery of traumatic brain injury(TBI)patients in the early postoperative stage.Methods We retrospectively analyzed the clinical data o...Objective To investigate the effects of propofol and sevoflurane on neurological recovery of traumatic brain injury(TBI)patients in the early postoperative stage.Methods We retrospectively analyzed the clinical data of TBI patients who underwent craniotomy or decompressive craniectomy.Generalized additive mixed model(GAMM)was used to analyze effects of propofol and sevoflurane on Glasgow Coma Scale(GCS)on postoperative days 1,3,and 7.Multivariate regression analysis was used to analyze effects of the two anesthetics on Glasgow Outcome Scale(GOS)at discharge.Results A total of 340 TBI patients were enrolled in this study.There were 110 TBI patients who underwent craniotomy including 75 in the propofol group and 35 in the sevoflurane group,and 134 patients who underwent decompressive craniectomy including 63 in the propofol group and 71 in the sevoflurane group.It showed no significant difference in GCS at admission between the propofol and the sevoflurane groups among craniotomy patients(β=0.75,95%CI:-0.55 to 2.05,P=0.260).However,elevation in GCS from baseline was 1.73 points(95%CI:-2.81 to-0.66,P=0.002)less in the sevoflurane group than that in the propofol group on postoperative day 1,2.03 points(95%CI:-3.14 to-0.91,P 0.001)less on day 3,and 1.31 points(95%CI:-2.43 to-0.19,P=0.022)less on day 7.The risk of unfavorable GOS(GOS 1,2,and 3)at discharge was higher in the sevoflurane group(OR=4.93,95%CI:1.05 to 23.03,P=0.043).No significant difference was observed among two-group decompressive craniectomy patients in GCS and GOS.Conclusions Compared to propofol,sevoflurane was associated with worse neurological recovery during the hospital stay in TBI patients undergoing craniotomy.This difference was not detected in TBI patients undergoing decompressive craniectomy.展开更多
Endorepellin plays a key role in the regulation of angiogenesis,but its effects on angiogenesis after traumatic brain injury are unclear.This study explored the effects of endorepellin on angiogenesis and neurobehavio...Endorepellin plays a key role in the regulation of angiogenesis,but its effects on angiogenesis after traumatic brain injury are unclear.This study explored the effects of endorepellin on angiogenesis and neurobehavioral outcomes after traumatic brain injury in mice.Mice were randomly divided into four groups:sham,controlled cortical impact only,adeno-associated virus(AAV)-green fluorescent protein,and AAV-shEndorepellin-green fluorescent protein groups.In the controlled cortical impact model,the transduction of AAV-shEndorepellin-green fluorescent protein downregulated endorepellin while increasing the number of CD31+/Ki-67+proliferating endothelial cells and the functional microvessel density in mouse brain.These changes resulted in improved neurological function compared with controlled cortical impact mice.Western blotting revealed increased expression of vascular endothelial growth factor and angiopoietin-1 in mice treated with AAV-shEndorepellin-green fluorescent protein.Synchrotron radiation angiography showed that endorepellin downregulation promoted angiogenesis and increased cortical neovascularization,which may further improve neurobehavioral outcomes.Furthermore,an in vitro study showed that downregulation of endorepellin increased tube formation by human umbilical vein endothelial cells compared with a control.Mechanistic analysis found that endorepellin downregulation may mediate angiogenesis by activating vascular endothelial growth factor-and angiopoietin-1-related signaling pathways.展开更多
For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein th...For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.展开更多
A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researche...A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researchers have begun to focus on nanocarriers and other brain-targeting drug delivery systems.In this review,we summarize the epidemiology,basic pathophysiology,current clinical treatment,the establishment of models,and the evaluation indicators that are commonly used for traumatic brain injury.We also report the current status of traumatic brain injury when treated with nanocarriers such as liposomes and vesicles.Nanocarriers can overcome a variety of key biological barriers,improve drug bioavailability,increase intracellular penetration and retention time,achieve drug enrichment,control drug release,and achieve brain-targeting drug delivery.However,the application of nanocarriers remains in the basic research stage and has yet to be fully translated to the clinic.展开更多
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen...Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.展开更多
Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen availability.In this context,mammals,which are probably the organisms that show one of the highes...Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen availability.In this context,mammals,which are probably the organisms that show one of the highest levels of metabolic complexity,have developed an elegant system that uses constant and rechargeable energy sources of modulate their metabolism.This homeostasis is especially important in the central nervous system,as neurons and other cells in the brain are highly susceptible to fluctuations in nutrients and oxygen availability.展开更多
Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,...Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal regrowth.During development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(Foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).展开更多
Efforts to promote recovery of function after human spinal cord injury(SCI) will likely require interventions to rgeting the corticospinal tract(CST) motor system:the most important pathway for voluntary motor control...Efforts to promote recovery of function after human spinal cord injury(SCI) will likely require interventions to rgeting the corticospinal tract(CST) motor system:the most important pathway for voluntary motor control in humans.This system has historically been the most refractory to regenerative efforts after SCI.The "nonregeneration" of the CST changed when robust regeneration of the CST into spared tissue was demonstrated by the inactivation of phosphatase and tensin homolog and delivery of inosine.展开更多
Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of biomedicine.And among these,the preventive-therapeutic approach to the treatment of brain...Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of biomedicine.And among these,the preventive-therapeutic approach to the treatment of brain trauma is one of the most striking examples.Traumatic brain injury(TBI)is a leading cause of brain damage among young and elderly populations with a very high hospitalization and death rate.TBI is characterized by two pathologically distinct but strictly consequential phases:a first characterized by an immediate and highly variable mechanical dysfunction of the brain tissue,which involves widespread cell death and tissue degeneration,followed by a second phase which can last from days to even years depending on the severity of the TBI and the patient’s pre-existing health status.Secondary processes,including inflammatory phenomena,oxidative stress associated with metabolic,vascular,and neuro-modulatory deficits,are very often responsible for neuro-motor and psychological deficits leading to long-term disabilities(Kaur and Sharma,2018).展开更多
Harmful and helpful roles of astrocytes in spinal cord injury(SCI):SCI induce gradable sensory,motor and autonomic impairments that correlate with the lesion severity and the rostro-caudal location of the injury site....Harmful and helpful roles of astrocytes in spinal cord injury(SCI):SCI induce gradable sensory,motor and autonomic impairments that correlate with the lesion severity and the rostro-caudal location of the injury site.The absence of spontaneous axonal regeneration after injury results from neuron-intrinsic and neuron-extrinsic parameters.Indeed,not only adult neurons display limited capability to regrow axons but also the injury environment contains inhibitors to axonal regeneration and a lack of growth-promoting factors.Amongst other cell populations that respond to the lesion,reactive astrocytes were first considered as only detrimental to spontaneous axonal regeneration.Indeed,astrocytes.展开更多
Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial ac...Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.展开更多
What is spinal cord injury:Spinal cord injury(SCI)is the damage to the structure of the bundles of cells and nerves that communicate signals from the brain to the body and extremities.The pathology of SCI includes bot...What is spinal cord injury:Spinal cord injury(SCI)is the damage to the structure of the bundles of cells and nerves that communicate signals from the brain to the body and extremities.The pathology of SCI includes both primary and secondary injuries(Morales et al.,2016).Physical forces such as compression,shearing,contusion,and tearing are major causes of primary injury in SCI.There are two main processes in primary injury:acute and subacute.The acute phase includes traumatic disruption of axons and hemorrhage of the blood vessels around the spinal cord.Hemorrhagic injury to the vessels can lead to increased edema within the neural and cord tissues,susceptibility to infiltration by microglia and astrocytes,excitotoxicity,and demyelination.Similarly,disruption of the blood-spinal cord barrier results in the release of inflammatory cytokines from specific cells and vessels.展开更多
文摘Microglia are one of the three glial cell populations in the central nervous system(CNS),along with astrocytes and oligodendrocytes.While microglia are unique among brain cells due to their hematologic origin and perform immune functions similar to peripheral macrophages,they are not simply macrophages of the CNS.
文摘AIM: To characterize and compare our current series of patients to prior reports in order to identify any changes in the incidence of neurological injury related to hunting accidents in Rochester, New York.METHODS: All tree stand-related injuries referred to our regional trauma center from September 2003 through November 2011 were reviewed. Information was obtained from the hospital's trauma registry and medical records were retrospectively reviewed for data pertaining to the injuries.RESULTS: Fifty-four patients were identified. Ninetysix percent of patients were male with a mean age of 47.9 years(range 15-69). The mean Injury Severity Score was 12.53 ± 1.17(range 2-34). The average height of fall was 18.2 feet(range 4-40 feet). All patients fell to the ground with the exception of one who landed on rocks, and many hit the tree or branches on the way down. A reason for the fall was documented in only 13 patients, and included tree stand construction(3), loss of balance(3), falling asleep(3), structural failure(2), safety harness breakage(3) or lightheadedness(1). The most common injuries were spinal fractures(54%), most commonly in the cervical spine(69%), followed by the thoracic(38%) and lumbar(21%) spine. Eight patients required operative repair. Head injuries occurred in 22%. Other systemic injuries include rib/clavicular fractures(47%), pelvic fractures(11%), solid organ injury(23%), and pneumothorax or hemothorax(19%). No patient deaths were reported. The average hospital length of stay was 6.56 ± 1.07 d. Most patients were discharged home without(72%) or with(11%) services and 17% required rehabilitation. CONCLUSION: Falls from hunting tree stands are still common, with a high rate of neurological injury. Compared to a decade ago we have made no progress in preventing these neurological injuries, despite an increase in safety advances. Neurosurgeons must continue to advocate for increased safety awareness and participate in leadership roles to improve outcomes for hunters.
文摘To investigate the effects of different degrees of hemodilution on neurological injury and amino acid content in different brain areas after deep hypothermic circulatory arrest (DHCA).Methods Forty-eight male adult SD rats weighing 400～450 g were randomly divided into 4 groups (n=12 each):group Ⅰ Hct 10%(H1);group Ⅱ Hct 20% (H2);group Ⅲ Hct 30%(H3) and control group (C).All animals except those in control group underwent DHCA at 18℃ for 90 min (includinhg cooling and rewarming) under general anesthesia with fentanyl,ketamine and droperidol.Different degrees of hemodilution were accomplised by changing the composition and volume of priming solution used in cardiopulmonary bypass (CPB).Hct was determined before,at the initiation of CPB and beginning of rewarming.PaO2,pH and blood lactate of arterial blood and SO2 of venous blood from internal jugular vein (SjvO2) were determined at the beginning and end of cooling and rewarming.The animals were killed and brains removed after recovery of circulatory function for the count of injured neurons and detemination of glutamate (Glu),aspartate (Asp),glycine (Gly),γ-aminobutyric acid (GABA) and taurine (Tau) contents in cortex,hippocampus and thalamus.Results The number of injured neurons in hippocampus and parietal cortex were significantly smaller in Hct 30% group than in the other two groups (P<0.05).The contents of the five amino acids in hippocampus and parietal cortex were all increased after DHCA.The Glu,Asp and Gly contents in hippocampus and parietal cortex were significantly lower in Hct 30% group than in the other 2 groups (P<0.05).There was no significant difference in GABA and Tau contents among the 3 groups.Conclusion Hemodilution at Hct 30% attenuates the neuronal injury after DHCA.The inhibition of the release of the excitatory amino acids in the brain may be involved in the mechanism of neuronal protection.13 refs,1 fig,3 tabs.
文摘Acquired neurological injuries initiate a pathological cascade of secondary injury processes,including inflammation,which continue for days to weeks following injury.Injury-induced neuroinflammation acts as a host defense mechanism contributing to the neutralization of the insult(removing offending factors)and restoring structure and function of the brain(establish homeostasis).The timing of these protective functions of the immune response is vital,since chronic
文摘BACKGROUND Elevated levels of cardiac troponin and abnormal electrocardiogram changes are the primary basis for clinical diagnosis of acute coronary syndrome(ACS).Troponin levels in ACS patients can often be more than 50 times the upper reference limit.Some patients with subarachnoid hemorrhage(SAH)also show electrocardiogram abnormalities,myocardial damage,and elevated cardiac biomarkers.Unlike ACS patients,patients with SAH only have a slight increase in troponin,and the use of anticoagulants or antiplatelet drugs is prohibited.Because of the opposite treatment modalities,it is essential for clinicians to distinguish between SAH and ACS.CASE SUMMARY A 56-year-old female patient was admitted to the emergency department at night with a sudden onset of severe back pain.The final diagnosis was intraspinal hematoma in the thoracic spine.We performed an emergency thoracic spinal canal hematoma evacuation procedure with the assistance of a microscope.Intraoperatively,diffuse hematoma formation was found in the T7-T10 spinal canal,and no obvious spinal vascular malformation changes were observed.Postoperative head and spinal magnetic resonance imaging(MRI)showed a small amount of SAH in the skull,no obvious abnormalities in the cervical and thoracic spinal canals,and no abnormal signals in the lumbar spinal canal.Thoracoab-dominal aorta computed tomography angiography showed no vascular malfor-mation.Postoperative motor system examination showed Medical Research Council Scale grade 1/5 strength in both lower extremities,and the patient experienced decreased sensation below the T12 rib margin and reported a Visual Analog Scale score of 3.CONCLUSION Extremely elevated troponin levels(more than 50 times the normal range)are not unique to coronary artery disease.SAH can also result in extremely high troponin levels,and antiplatelet drugs are contraindicated in such cases.Emergency MRI can help in the early differential diagnosis,as a misdiagnosis of ACS can lead to catastrophic neurological damage in patients with spontaneous spinal SAH.
基金supported by the President Foundation of Nanfang Hospital,Southern Medical University,No.2016Z003(50107021)(to JZF).
文摘Studies have shown that repetitive transcra nial magnetic stimulation(rTMS)can enhance synaptic plasticity and improve neurological dysfunction.Howeve r,the mechanism through which rTMS can improve moderate traumatic brain injury remains poorly understood.In this study,we established rat models of moderate traumatic brain injury using Feeney's weight-dropping method and treated them using rTMS.To help determine the mechanism of action,we measured levels of seve ral impo rtant brain activity-related proteins and their mRNA.On the injured side of the brain,we found that rTMS increased the protein levels and mRNA expression of brain-derived neurotrophic factor,tropomyosin receptor kinase B,N-methyl-D-aspartic acid receptor 1,and phosphorylated cAMP response element binding protein,which are closely associated with the occurrence of long-term potentiation.rTMS also partially reve rsed the loss of synaptophysin after injury and promoted the remodeling of synaptic ultrastructure.These findings suggest that upregulation of synaptic plasticity-related protein expression is the mechanism through which rTMS promotes neurological function recovery after moderate traumatic brain injury.
基金supported by the National Natural Science Foundation of China,Nos.81871785 and 81672161(both to ZSY)。
文摘Ferroptosis is one of the critical pathological events in spinal cord injury.Erythropoietin has been reported to improve the recovery of spinal cord injury.However,whether ferroptosis is involved in the neuroprotective effects of erythropoietin on spinal cord injury has not been examined.In this study,we established rat models of spinal cord injury by modified Allen’s method and intraperitoneally administered 1000 and 5000 IU/kg erythropoietin once a week for 2 successive weeks.Both low and high doses of erythropoietin promoted recovery of hindlimb function,and the high dose of erythropoietin led to better outcome.High dose of erythropoietin exhibited a stronger suppressive effect on ferroptosis relative to the low dose of erythropoietin.The effects of erythropoietin on inhibiting ferroptosis-related protein expression and restoring mitochondrial morphology were similar to those of Fer-1(a ferroptosis suppressor),and the effects of erythropoietin were largely diminished by RSL3(ferroptosis activator).In vitro experiments showed that erythropoietin inhibited RSL3-induced ferroptosis in PC12 cells and increased the expression of xCT and Gpx4.This suggests that xCT and Gpx4 are involved in the neuroprotective effects of erythropoietin on spinal cord injury.Our findings reveal the underlying anti-ferroptosis role of erythropoietin and provide a potential therapeutic strategy for treating spinal cord injury.
文摘Chronic compressive spinal cord injury in compressive cervical myelopathy conditions can lead to rapid neurological deterioration in the early phase,followed by partial self-recovery,and ultimately an equilibrium state of neurological dysfunction.Ferroptosis is a crucial pathological process in many neurodegenerative diseases;however,its role in chro nic compressive spinal cord injury remains unclear.In this study,we established a chronic compressive spinal cord injury rat model,which displayed its most severe behavioral and electrophysiological dysfunction at 4 wee ks and partial recovery at 8 weeks after compression.Bulk RNA sequencing data identified enriched functional pathways,including ferroptosis,presynapse,and postsynaptic membrane activity at both 4 and 8 wee ks following chro nic compressive spinal co rd injury.Tra nsmission electron microscopy and malondialdehyde quantification assay confirmed that ferroptosis activity peaked at 4 weeks and was attenuated at 8 weeks after chronic compression.Ferro ptosis activity was negatively correlated with behavioral score.Immunofluorescence,quantitative polymerase chain reaction,and western blotting showed that expression of the anti-ferroptosis molecules,glutathione peroxidase 4(GPX4) and MAF BZIP transcription factor G(MafG),in neuro ns was suppressed at 4 weeks and upregulated at 8 weeks following spinal co rd compression.There was a positive correlation between the expression of these two molecules,suggesting that they may work together to contribute to functional recovery following chronic compressive spinal cord injury.In conclusion,our study determined the genome-wide expression profile and fe rroptosis activity of a consistently compressed spinal cord at different time points.The results showed that anti-fe rroptosis genes,specifically GPX4 and MafG,may be involved in spontaneous neurological recovery at 8 weeks of chronic compressive spinal cord injury.These findings contribute to a better understanding of the mechanisms underlying chronic compressive spinal cord injury and may help identify new therapeutic targets for compressive cervical myelopathy.
基金Beijing Natural Sciences Foundation(7173255)Beijing Municipal Administration of Hospital Incubating Program(PX2019019).
文摘Objective To investigate the effects of propofol and sevoflurane on neurological recovery of traumatic brain injury(TBI)patients in the early postoperative stage.Methods We retrospectively analyzed the clinical data of TBI patients who underwent craniotomy or decompressive craniectomy.Generalized additive mixed model(GAMM)was used to analyze effects of propofol and sevoflurane on Glasgow Coma Scale(GCS)on postoperative days 1,3,and 7.Multivariate regression analysis was used to analyze effects of the two anesthetics on Glasgow Outcome Scale(GOS)at discharge.Results A total of 340 TBI patients were enrolled in this study.There were 110 TBI patients who underwent craniotomy including 75 in the propofol group and 35 in the sevoflurane group,and 134 patients who underwent decompressive craniectomy including 63 in the propofol group and 71 in the sevoflurane group.It showed no significant difference in GCS at admission between the propofol and the sevoflurane groups among craniotomy patients(β=0.75,95%CI:-0.55 to 2.05,P=0.260).However,elevation in GCS from baseline was 1.73 points(95%CI:-2.81 to-0.66,P=0.002)less in the sevoflurane group than that in the propofol group on postoperative day 1,2.03 points(95%CI:-3.14 to-0.91,P 0.001)less on day 3,and 1.31 points(95%CI:-2.43 to-0.19,P=0.022)less on day 7.The risk of unfavorable GOS(GOS 1,2,and 3)at discharge was higher in the sevoflurane group(OR=4.93,95%CI:1.05 to 23.03,P=0.043).No significant difference was observed among two-group decompressive craniectomy patients in GCS and GOS.Conclusions Compared to propofol,sevoflurane was associated with worse neurological recovery during the hospital stay in TBI patients undergoing craniotomy.This difference was not detected in TBI patients undergoing decompressive craniectomy.
基金supported by the National Natural Science Foundation of China,Nos.81801236(to ZX),81974189(to HT)a grant from Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,No.ynlc201719(to QZ).
文摘Endorepellin plays a key role in the regulation of angiogenesis,but its effects on angiogenesis after traumatic brain injury are unclear.This study explored the effects of endorepellin on angiogenesis and neurobehavioral outcomes after traumatic brain injury in mice.Mice were randomly divided into four groups:sham,controlled cortical impact only,adeno-associated virus(AAV)-green fluorescent protein,and AAV-shEndorepellin-green fluorescent protein groups.In the controlled cortical impact model,the transduction of AAV-shEndorepellin-green fluorescent protein downregulated endorepellin while increasing the number of CD31+/Ki-67+proliferating endothelial cells and the functional microvessel density in mouse brain.These changes resulted in improved neurological function compared with controlled cortical impact mice.Western blotting revealed increased expression of vascular endothelial growth factor and angiopoietin-1 in mice treated with AAV-shEndorepellin-green fluorescent protein.Synchrotron radiation angiography showed that endorepellin downregulation promoted angiogenesis and increased cortical neovascularization,which may further improve neurobehavioral outcomes.Furthermore,an in vitro study showed that downregulation of endorepellin increased tube formation by human umbilical vein endothelial cells compared with a control.Mechanistic analysis found that endorepellin downregulation may mediate angiogenesis by activating vascular endothelial growth factor-and angiopoietin-1-related signaling pathways.
基金supported by Hong Kong Spinal Cord Injury Fund (HKSCIF),China (to HZ)。
文摘For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.
基金supported by the Natural Science Foundation of Beijing,No.L222126(to LD)。
文摘A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researchers have begun to focus on nanocarriers and other brain-targeting drug delivery systems.In this review,we summarize the epidemiology,basic pathophysiology,current clinical treatment,the establishment of models,and the evaluation indicators that are commonly used for traumatic brain injury.We also report the current status of traumatic brain injury when treated with nanocarriers such as liposomes and vesicles.Nanocarriers can overcome a variety of key biological barriers,improve drug bioavailability,increase intracellular penetration and retention time,achieve drug enrichment,control drug release,and achieve brain-targeting drug delivery.However,the application of nanocarriers remains in the basic research stage and has yet to be fully translated to the clinic.
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Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.
基金RTDC postdoctoral fellowship is defrayed by an AHA Supplement to Promote Diversity in Science.MES is funded by AHA(Career Development Award),Rutgers University(StartUp Funds),and NIH(R00AG055701).
文摘Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen availability.In this context,mammals,which are probably the organisms that show one of the highest levels of metabolic complexity,have developed an elegant system that uses constant and rechargeable energy sources of modulate their metabolism.This homeostasis is especially important in the central nervous system,as neurons and other cells in the brain are highly susceptible to fluctuations in nutrients and oxygen availability.
基金supported by grants from The University of Connecticut School of Medicine (StartUp Fund)the National Institutes of Health (NIH)(Grant R01-EY029 739)+1 种基金the Connecticut Institute for the Brain and Cognitive Sciences (Research Seed Grant)the BrightFocus Foundation (Grant G2017204)(all to EFT)
文摘Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal regrowth.During development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(Foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).
基金supported by the Veterans Administration (I01RX002264-01A2)(to PL)Wings For Life (WFL-US-10/21)(to CMF)。
文摘Efforts to promote recovery of function after human spinal cord injury(SCI) will likely require interventions to rgeting the corticospinal tract(CST) motor system:the most important pathway for voluntary motor control in humans.This system has historically been the most refractory to regenerative efforts after SCI.The "nonregeneration" of the CST changed when robust regeneration of the CST into spared tissue was demonstrated by the inactivation of phosphatase and tensin homolog and delivery of inosine.
文摘Is it better to be safe than sorry?This Hamletic dilemma has always stimulated medical-scientific debates in numerous fields of biomedicine.And among these,the preventive-therapeutic approach to the treatment of brain trauma is one of the most striking examples.Traumatic brain injury(TBI)is a leading cause of brain damage among young and elderly populations with a very high hospitalization and death rate.TBI is characterized by two pathologically distinct but strictly consequential phases:a first characterized by an immediate and highly variable mechanical dysfunction of the brain tissue,which involves widespread cell death and tissue degeneration,followed by a second phase which can last from days to even years depending on the severity of the TBI and the patient’s pre-existing health status.Secondary processes,including inflammatory phenomena,oxidative stress associated with metabolic,vascular,and neuro-modulatory deficits,are very often responsible for neuro-motor and psychological deficits leading to long-term disabilities(Kaur and Sharma,2018).
基金supported by the patient organizations“Verticale”(to YNG and FEP).
文摘Harmful and helpful roles of astrocytes in spinal cord injury(SCI):SCI induce gradable sensory,motor and autonomic impairments that correlate with the lesion severity and the rostro-caudal location of the injury site.The absence of spontaneous axonal regeneration after injury results from neuron-intrinsic and neuron-extrinsic parameters.Indeed,not only adult neurons display limited capability to regrow axons but also the injury environment contains inhibitors to axonal regeneration and a lack of growth-promoting factors.Amongst other cell populations that respond to the lesion,reactive astrocytes were first considered as only detrimental to spontaneous axonal regeneration.Indeed,astrocytes.
基金supported by Canadian Institutes for Health Research (CIHR)(to ADR and WW)Ontario Graduate Scholarship (to NOB)+2 种基金Alzheimer's Society of CanadaHeart and Stroke Foundation of Canada,CIHRthe Canadian Consortium for Neurodegeneration and Aging (CCNA)(to SNW)。
文摘Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022R1C1C1005410)(to GWL).
文摘What is spinal cord injury:Spinal cord injury(SCI)is the damage to the structure of the bundles of cells and nerves that communicate signals from the brain to the body and extremities.The pathology of SCI includes both primary and secondary injuries(Morales et al.,2016).Physical forces such as compression,shearing,contusion,and tearing are major causes of primary injury in SCI.There are two main processes in primary injury:acute and subacute.The acute phase includes traumatic disruption of axons and hemorrhage of the blood vessels around the spinal cord.Hemorrhagic injury to the vessels can lead to increased edema within the neural and cord tissues,susceptibility to infiltration by microglia and astrocytes,excitotoxicity,and demyelination.Similarly,disruption of the blood-spinal cord barrier results in the release of inflammatory cytokines from specific cells and vessels.
