Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently understood.As potent anti-i...Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently understood.As potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet known.In the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of action.In vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial polarization.Lipopolysaccharide,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were administered.RNA-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of dexamethasone.The Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our hypothesis.High-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain injury.Thus dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in vivo.Glucocorticoid receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain injury.Additionally,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is the GR/JAK1/STAT3 pathway.Overactivation of glucocorticoid receptor by high-dose dexamethasone reduced the expression of M2 microglia,which plays an antiinflammatory role.In contrast,inhibiting the activation of glucocorticoid receptor reduced the number of apoptotic glia and neurons and decreased the loss of dendritic spines after traumatic brain injury.Dexamethasone may exe rt its neurotoxic effects by inhibiting M2 microglia through the GR/JAK1/STAT3 signaling pathway.展开更多
After brain injury, infiltration and abnormal activation of neutrophils damages brain tissue and worsens inflammation, but the mediators that connect activated neutrophils with neuroinflammation have not yet been full...After brain injury, infiltration and abnormal activation of neutrophils damages brain tissue and worsens inflammation, but the mediators that connect activated neutrophils with neuroinflammation have not yet been fully clarified. To identify regulators of neutrophil-mediated neuroinflammation after traumatic brain injury, a mouse model of traumatic brain injury was established by controlled cortical impact. At 7 days post-injury(sub-acute phase), genome-wide transcriptomic data showed that interleukin 17 A-associated signaling pathways were markedly upregulated, suggesting that interleukin 17 A may be involved in neuroinflammation. Double immunofluorescence staining showed that interleukin 17 A was largely secreted by neutrophils rather than by glial cells and neurons. Furthermore, nuclear factor-kappaB and Stat3, both of which are important effectors in interleukin 17 A-mediated proinflammatory responses, were significantly activated. Collectively, our findings suggest that neutrophil-derived interleukin 17 A participates in neutrophil-mediated neuroinflammation during the subacute phase of traumatic brain injury. Therefore, interleukin 17 A may be a promising therapeutic target for traumatic brain injury.展开更多
Proteomics is a powerful tool that can be used to elucidate the underlying mechanisms of diseases and identify new biomarkers.Therefore,it may also be helpful for understanding the detailed pathological mechanism of t...Proteomics is a powerful tool that can be used to elucidate the underlying mechanisms of diseases and identify new biomarkers.Therefore,it may also be helpful for understanding the detailed pathological mechanism of traumatic brain injury(TBI).In this study,we performed Tandem Mass Tag-based quantitative analysis of cortical proteome profiles in a mouse model of TBI.Our results showed that there were 302 differentially expressed proteins in TBI mice compared with normal mice 7 days after injury.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that these differentially expressed proteins were predominantly involved in inflammatory responses,including complement and coagulation cascades,as well as chemokine signaling pathways.Subsequent transcription factor analysis revealed that the inflammation-related transcription factors NF-κB1,RelA,IRF1,STAT1,and Spi1 play pivotal roles in the secondary injury that occurs after TBI,which further corroborates the functional enrichment for inflammatory factors.Our results suggest that inflammation-related proteins and inflammatory responses are promising targets for the treatment of TBI.展开更多
The heterogeneity of traumatic brain injury(TBI)-induced secondary injury has greatly hampered the development of effective treatments for TBI patients.Targeting common processes across species may be an innovative st...The heterogeneity of traumatic brain injury(TBI)-induced secondary injury has greatly hampered the development of effective treatments for TBI patients.Targeting common processes across species may be an innovative strategy to combat debilitating TBI.In the present study, a cross-species transcriptome comparison was performed for the first time to determine the fundamental processes of secondary brain injury in Sprague-Dawley rat and C57/BL6 mouse models of TBI, caused by acute controlled cortical impact.The RNA sequencing data from the mouse model of TBI were downloaded from the Gene Expression Omnibus(ID: GSE79441) at the National Center for Biotechnology Information.For the rat data, peri-injury cerebral cortex samples were collected for transcriptomic analysis 24 hours after TBI.Differentially expressed gene-based functional analysis revealed that common features between the two species were mainly involved in the regulation and activation of the innate immune response, including complement cascades as well as Toll-like and nucleotide oligomerization domain-like receptor pathways.These findings were further corroborated by gene set enrichment analysis.Moreover, transcription factor analysis revealed that the families of signal transducers and activators of transcription(STAT), basic leucine zipper(BZIP), Rel homology domain(RHD), and interferon regulatory factor(IRF) transcription factors play vital regulatory roles in the pathophysiological processes of TBI, and are also largely associated with inflammation.These findings suggest that targeting the common innate immune response might be a promising therapeutic approach for TBI.The animal experimental procedures were approved by the Beijing Neurosurgical Institute Animal Care and Use Committee(approval No.201802001) on June 6, 2018.展开更多
Transfer RNA(t RNA)-derived small RNAs(ts RNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that ts RNAs are involved in...Transfer RNA(t RNA)-derived small RNAs(ts RNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that ts RNAs are involved in neurological disorders and play a role in the pathogenesis of neurodegenerative disease. However, whether ts RNAs are involved in traumatic brain injury-induced secondary injury remains poorly understood. In this study, a mouse controlled cortical impact model of traumatic brain injury was established, and integrated ts RNA and messenger RNA(m RNA) transcriptome sequencing were used. The results revealed that 103 ts RNAs were differentially expressed in the mouse model of traumatic brain injury at 72 hours, of which 56 ts RNAs were upregulated and 47 ts RNAs were downregulated. Based on micro RNA-like seed matching and Pearson correlation analysis, 57 differentially expressed ts RNA-m RNA interaction pairs were identified, including 29 ts RNAs and 26 m RNAs. Moreover, Gene Ontology annotation of target genes revealed that the significantly enriched terms were primarily associated with inflammation and synaptic function. Collectively, our findings suggest that ts RNAs may be associated with traumatic brain injury-induced secondary brain injury, and are thus a potential therapeutic target for traumatic brain injury. The study was approved by the Beijing Neurosurgical Institute Animal Care and Use Committee(approval No. 20190411) on April 11, 2019.展开更多
Dexamethasone has been widely used after various neurosurgical procedures due to its anti-inflammatory property and the abilities to restore vascular permeability,inhibit free radicals,and reduce cerebrospinal fluid p...Dexamethasone has been widely used after various neurosurgical procedures due to its anti-inflammatory property and the abilities to restore vascular permeability,inhibit free radicals,and reduce cerebrospinal fluid production.According to the latest guidelines for the treatment of traumatic brain injury in the United States,high-dose glucocorticoids cause neurological damage.To investigate the reason why high-dose glucocorticoids after traumatic brain injury exhibit harmful effect,rat controlled cortical impact models of traumatic brain injury were established.At 1 hour and 2 days after surgery,rat models were intraperitoneally administered dexamethasone 10 mg/kg.The results revealed that 31 proteins were significantly upregulated and 12 proteins were significantly downregulated in rat models of traumatic brain injury after dexamethasone treatment.The Ingenuity Pathway Analysis results showed that differentially expressed proteins were enriched in the mitochondrial dysfunction pathway and synaptogenesis signaling pathway.Western blot analysis and immunohistochemistry results showed that Ndufv2,Maob and Gria3 expression and positive cell count in the dexamethasone-treated group were significantly greater than those in the model group.These findings suggest that dexamethasone may promote a compensatory increase in complex I subunits(Ndufs2 and Ndufv2),increase the expression of mitochondrial enzyme Maob,and upregulate synaptic-transmission-related protein Gria3.These changes may be caused by nerve injury after traumatic brain injury treatment by dexamethasone.The study was approved by Institutional Ethics Committee of Beijing Neurosurgical Institute(approval No.201802001)on June 6,2018.展开更多
The mechanism of multinucleon transfer reactions has been investigated within the dinuclear system model, in which the sequential nucleon transfer is described by solving a set of microscopically derived master equati...The mechanism of multinucleon transfer reactions has been investigated within the dinuclear system model, in which the sequential nucleon transfer is described by solving a set of microscopically derived master equations. The transfer dynamics in the reaction of^(136)Xe+^(208)Pb near Coulomb barrier energies is thoroughly analyzed. It is found that the total kinetic energies of primary fragments are dissipated from the relative motion energy of two touching nuclei and exhibit a symmetric distribution along the fragment mass. The angular distribution of the projectile-like fragments moves forward with increasing beam energy. However, the target-like fragments exhibit an opposite trend. The shell effect is pronounced due to the fragment yields in multinucleon transfer reactions.展开更多
Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate so...Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate solution.The effects ofiron-containing phases on the transformation of sulfur-bearing ions(S2?,223S O?,23SO?and24SO?)in sodium aluminate solutionwere investigated.Fe,Fe2O3and Fe3O4barely react with23SO?and24SO?,but all of them,particularly Fe,can promote theconversion of223S O?to23SO?and S2?in sodium aluminate solution.Fe can convert to3Fe(OH)?in solution at elevatedtemperatures,and further react with S2?to form FeS2,but Fe2O3and Fe3O4have little influence on the reaction behavior of S2?insodium aluminate solution.Increasing temperature,duration,dosage of Fe,mole ratio of Na2Ok to Al2O3and caustic sodaconcentration are beneficial to the transformation of223S O?to23SO?and S2?.The results may contribute to the development oftechnologies for alleviating the equipment corrosion and reducing caustic consumption during the high-sulfur bauxite treatment bythe Bayer process.展开更多
The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system model.The Monte Carlo approach was implemented in the nucleon transfer process to include all possib...The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system model.The Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear fragments.The production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from Dubna.The evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically analyzed.The combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?122.We obtained that the production cross sections sensitively depend on the neutron richness of the reaction system.The structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.展开更多
Within the framework of the dinuclear system model,the multinucleon transfer dynamics for nearly symmetric nuclear collisions has been investigated.The reaction mechanism in the systems of 198Pt+198Pt and 204Hg+198Pt ...Within the framework of the dinuclear system model,the multinucleon transfer dynamics for nearly symmetric nuclear collisions has been investigated.The reaction mechanism in the systems of 198Pt+198Pt and 204Hg+198Pt was investigated at beam energies around the Coulomb barrier.It was found that the isotopic yields are enhanced with increased incident energy in the domain of proton-rich nuclides.However,the production on the neutron-rich side weakly depends on the energy.The angular distribution with the beam energy was also analyzed in the multinucleon transfer reactions.Projectile-like fragments were produced toward the forward emission with increasing incident energy.The target-like fragments manifested the opposite trend in the transfer reactions.展开更多
Electroless Cu plating was used for flake G powder and CNTs, Cu-G-CNTs （copper/graphite/carbon nanotubes） composites were manufactured by means of powder metallurgical method. The influences of CNTs on the mechanica...Electroless Cu plating was used for flake G powder and CNTs, Cu-G-CNTs （copper/graphite/carbon nanotubes） composites were manufactured by means of powder metallurgical method. The influences of CNTs on the mechanical properties, conductivity properties, friction, and wear performance of the composite were examined. The results indicate that adding a small amount of CNTs can improve comprehensive property of the composites, especially mechanical property. However, excessive CNT, which is easily winding reunion and grain boundary seg- regation, results in performances degradation.展开更多
Small and isolated populations face several intrinsic risks,such as genetic drift,inbreeding depression,and reduced gene fow.Thus,patterns of genetic diversity and differentiation have become an important focus of con...Small and isolated populations face several intrinsic risks,such as genetic drift,inbreeding depression,and reduced gene fow.Thus,patterns of genetic diversity and differentiation have become an important focus of conservation genetics research.The golden snub-nosed monkey Rhinopithecus roxellana,an endangered species endemic to China,has experienced rapid reduction in population size and severe population fragmentation over the past few decades.We measured the patterns of genetic diversity and population differentiation using both neutral microsatellites and adaptive major histocompatibility complex(MHC)genes in 2 R.roxellana populations(DPY and GNG)distributed on the northern and southern slopes of the Qinling Mountains,respectively.Eight MHC-linked haplotypes formed by 5 DQA1 alleles,5 DQB1 alleles,5 DRB1 alleles,and 4 DRB2 alleles were detected in the 2 populations.The larger GNG population showed higher genetic variation for both MHC and microsatellites than the smaller DPY population,suggesting an effect of genetic drift on genetic variation.Genetic differentiation index(FST)outlier analyses,principal coordinate analysis(PCoA),and inferred population genetic structure showed lower genetic differentiation in the MHC variations than microsatellites,suggesting that pathogen-mediated balancing selection,rather than local adaptation,homogenized the MHC genes of both populations.This study indicates that both balancing selection and genetic drift may shape genetic variation and differentiation in small and fragmented populations.展开更多
Infanticide,killing unweaned offspring in conspecifics,occurs widely among mammals,such as rodents,ungulates,and carnivores,especially in primates(Lukas and Huchard 2014).Such scenarios are often triggered by intruder...Infanticide,killing unweaned offspring in conspecifics,occurs widely among mammals,such as rodents,ungulates,and carnivores,especially in primates(Lukas and Huchard 2014).Such scenarios are often triggered by intruders that have replaced the former dominant males in nonhuman primates(Borries 1997).It has widely been viewed that infanticide is one of the solutions of sexually driven evolutionary selection:males kill infants to end lactational amenorrhea of the victim's mothers,forcing them to return to estrus and providing infanticidal males with the opportunities to sire their new offspring(Hrdy 1979).There is a broad spectrum regarding the patterns and mechanisms causing such events,referring to alternative breeding behaviors and mating systems-monogamy,polyandry,polygyny,and promiscuity(Qi et al.2020).展开更多
Traumatic brain injury(TBI),a growing public health problem,is a leading cause of death and disability worldwide,although its prevention measures and clinical cares are substantially improved.Increasing evidence shows...Traumatic brain injury(TBI),a growing public health problem,is a leading cause of death and disability worldwide,although its prevention measures and clinical cares are substantially improved.Increasing evidence shows that TBI may increase the risk of mood disorders and neurodegenerative diseases,including Alzheimer’s disease(AD).However,the complex relationship between TBI and AD remains elusive.Metabolic dysfunction has been the common pathology in both TBI and AD.On the one hand,TBI perturbs the glucose metabolism of the brain,and causes energy crisis and subsequent hyperglycolysis.On the other hand,glucose deprivation promotes amyloidogenesis viaβ-site APP cleaving enzyme-1 dependent mechanism,and triggers tau pathology and synaptic function.Recent findings suggest that TBI might facilitate Alzheimer’s pathogenesis by altering metabolism,which provides clues to metabolic link between TBI and AD.In this review,we will explore how TBI-induced metabolic changes contribute to the development of AD.展开更多
SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of ...SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of cobalt-induced SmF_(3)for preparing SmCo_(5)alloy is feasible.An alloy with 33.89 wt%samarium and a yield of 96.45%were achieved under the optimal conditions of 10%and 20%excess of SmF_(3)and calcium over the stoichiometry,respectively,and 1450℃for 4 min.The X-ray diffraction results show that the reduction products are SmCo_(5)alloy and CaF_(2).The scanning electron microscopy micrograph of the SmCo_(5)alloy ingot exhibits a distinct dendritic morphology composed of samarium and cobalt.The X-ray photoelectron spectroscopy shows that the atomic ratio of samarium to cobalt is approximately 1:5 and both elements demonstrate zero valency(Sm^(0),Co^(0)).The magnetic properties measurement of the SmCo_(5)alloy melt-spun ribbon shows the remanent magnetization B_r=0.59 T,intrinsic coercivity H_(Ci)=345.82 kA/m and maximum magnetic energy density(BH)_(max)=42.20 kJ/m^(3).These results may be helpful for the development of novel valence-variable rare-earth alloys.展开更多
The isospin effect in peripheral heavy-ion collisions was thoroughly investigated within the framework of the Lanzhou quantum molecular dynamics （LQMD） transport model. A coalescence approach was used to recognize t...The isospin effect in peripheral heavy-ion collisions was thoroughly investigated within the framework of the Lanzhou quantum molecular dynamics （LQMD） transport model. A coalescence approach was used to recognize the primary fragments formed in nucleus-nucleus collisions. described using the statistical code GEMINI. The production The secondary decay process of these fragments was mechanism and isospin effect of the projectile-like and target-like fragments were analyzed using the combined approach. It was found that the isospin migration from the high-isospin density to the low-density matter occurred in the neutron-rich nuclear reactions, i.e., ^48Ca＋^208Pb, ^86Kr＋^48SCa/^208Pb/^124Sn,^136Xe＋^208Pb, ^124Sn＋^124Sn, and ^136Xe＋^136Xe. A hard symmetry energy was available for creating the neutron-rich fragments, particularly in the medium-mass region. The isospin effect of the neutron-to- proton （n/p） ratio of the complex fragments was reduced when the secondary decay process was included. However, a soft symmetry energy enhanced the n/p ratio of the light particles, particularly at kinetic energies greater than 15 MeV/nucleon.展开更多
Neodymium naphthenate-loaded organic phase stripping using sodium oxalate solution was studied to explore the feasibility of synchronous rare earth-loaded organic phase stripping,rare earth precipitation,and blank org...Neodymium naphthenate-loaded organic phase stripping using sodium oxalate solution was studied to explore the feasibility of synchronous rare earth-loaded organic phase stripping,rare earth precipitation,and blank organic phase saponification.Experimental results show that loaded organic phase stripping,rare earth precipitation,and blank organic phase saponification can be realized simultaneously.When using 20% excess of sodium oxalate over the stoichiometry with the volume ratio of organic phase to aqueous phase of 1:1 at 25℃ for 40 min,the single stage stripping rate and saponification value are about 40% and 0.29 mol/L,respectively.After 16 stages of countercurrent continuous stripping,the stripping rate of neodymium can reach 99%,the saponification value is 0.42 mol/L,the Nd^(3+) concentration in saponified organic phase is less than 0.0020 mol/L,and the main phase in precipitation isNd_(2)(C2 O_(4))3·10 H_(2) O.Afterwards,this saponified organic phase can be used in the extraction of NdCl_(3) solution,and then the loaded organic phases(neodymium naphthenate) with 0.16 mol/L Nd^(3+) can be retrieved.The morphology,particle size distribution,and composition of theNd_(2)(C2 O_(4))3·10 H_(2) O products are similar to those of the current direct precipitation products.The neodymium oxide prepared by continuous calcination of neodymium oxalate meets the national standard of China(GB/T 5240-2015).These results prove the feasibility of stripping neodymium naphthenate-loaded organic phase by using sodium oxalate solution.Sodium oxalate can serve as a stripping agent,a saponifier,and a precipitator,thereby simplifying rare earth extraction and separation.This study provides theoretical and technical support for the development of a novel method for rare earth extraction and separation.展开更多
基金supported by research grants from the Ningbo Science and Technology Plan Project,No.2022Z143hezuo(to BL)the National Natural Science Foundation of China,No.82201520(to XD)。
文摘Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently understood.As potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet known.In the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of action.In vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial polarization.Lipopolysaccharide,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were administered.RNA-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of dexamethasone.The Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our hypothesis.High-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain injury.Thus dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in vivo.Glucocorticoid receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain injury.Additionally,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is the GR/JAK1/STAT3 pathway.Overactivation of glucocorticoid receptor by high-dose dexamethasone reduced the expression of M2 microglia,which plays an antiinflammatory role.In contrast,inhibiting the activation of glucocorticoid receptor reduced the number of apoptotic glia and neurons and decreased the loss of dendritic spines after traumatic brain injury.Dexamethasone may exe rt its neurotoxic effects by inhibiting M2 microglia through the GR/JAK1/STAT3 signaling pathway.
基金supported by the National Natural Science Foundation of China,No. 81771327 (to BYL)Construction of Central Nervous System Injury Basic Science and Clinical Translational Research PlatformBudget of Beijing Municipal Health Commission 2020, No. PXM2020_026280_000002 (BYL)。
文摘After brain injury, infiltration and abnormal activation of neutrophils damages brain tissue and worsens inflammation, but the mediators that connect activated neutrophils with neuroinflammation have not yet been fully clarified. To identify regulators of neutrophil-mediated neuroinflammation after traumatic brain injury, a mouse model of traumatic brain injury was established by controlled cortical impact. At 7 days post-injury(sub-acute phase), genome-wide transcriptomic data showed that interleukin 17 A-associated signaling pathways were markedly upregulated, suggesting that interleukin 17 A may be involved in neuroinflammation. Double immunofluorescence staining showed that interleukin 17 A was largely secreted by neutrophils rather than by glial cells and neurons. Furthermore, nuclear factor-kappaB and Stat3, both of which are important effectors in interleukin 17 A-mediated proinflammatory responses, were significantly activated. Collectively, our findings suggest that neutrophil-derived interleukin 17 A participates in neutrophil-mediated neuroinflammation during the subacute phase of traumatic brain injury. Therefore, interleukin 17 A may be a promising therapeutic target for traumatic brain injury.
基金supported by the National Natural Science Foundation of China,No. 81771327a grant for the Platform Construction of Basic Research and Clinical Translation of Nervous System Injury,China,No. PXM2020_026280_000002 (both to BYL)
文摘Proteomics is a powerful tool that can be used to elucidate the underlying mechanisms of diseases and identify new biomarkers.Therefore,it may also be helpful for understanding the detailed pathological mechanism of traumatic brain injury(TBI).In this study,we performed Tandem Mass Tag-based quantitative analysis of cortical proteome profiles in a mouse model of TBI.Our results showed that there were 302 differentially expressed proteins in TBI mice compared with normal mice 7 days after injury.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that these differentially expressed proteins were predominantly involved in inflammatory responses,including complement and coagulation cascades,as well as chemokine signaling pathways.Subsequent transcription factor analysis revealed that the inflammation-related transcription factors NF-κB1,RelA,IRF1,STAT1,and Spi1 play pivotal roles in the secondary injury that occurs after TBI,which further corroborates the functional enrichment for inflammatory factors.Our results suggest that inflammation-related proteins and inflammatory responses are promising targets for the treatment of TBI.
基金supported by the National Natural Science Foundation of China, Nos.81471238, 81771327(both to BYL)Construction of Central Nervous System Injury Basic Science and Clinical Translational Research Platform, Budget of Beijing Municipal Health Commission 2020, No.PXM2020_026280_000002(to BYL)。
文摘The heterogeneity of traumatic brain injury(TBI)-induced secondary injury has greatly hampered the development of effective treatments for TBI patients.Targeting common processes across species may be an innovative strategy to combat debilitating TBI.In the present study, a cross-species transcriptome comparison was performed for the first time to determine the fundamental processes of secondary brain injury in Sprague-Dawley rat and C57/BL6 mouse models of TBI, caused by acute controlled cortical impact.The RNA sequencing data from the mouse model of TBI were downloaded from the Gene Expression Omnibus(ID: GSE79441) at the National Center for Biotechnology Information.For the rat data, peri-injury cerebral cortex samples were collected for transcriptomic analysis 24 hours after TBI.Differentially expressed gene-based functional analysis revealed that common features between the two species were mainly involved in the regulation and activation of the innate immune response, including complement cascades as well as Toll-like and nucleotide oligomerization domain-like receptor pathways.These findings were further corroborated by gene set enrichment analysis.Moreover, transcription factor analysis revealed that the families of signal transducers and activators of transcription(STAT), basic leucine zipper(BZIP), Rel homology domain(RHD), and interferon regulatory factor(IRF) transcription factors play vital regulatory roles in the pathophysiological processes of TBI, and are also largely associated with inflammation.These findings suggest that targeting the common innate immune response might be a promising therapeutic approach for TBI.The animal experimental procedures were approved by the Beijing Neurosurgical Institute Animal Care and Use Committee(approval No.201802001) on June 6, 2018.
基金supported by grants from the National Natural Science Foundation of China,Nos.81471238,81771327Construction of Central Nervous System Injury Basic Science and Clinical Translational Research Platform,Budget of Beijing Municipal Health Commission 2020,No.PXM2020_026280_000002(all to BYL)。
文摘Transfer RNA(t RNA)-derived small RNAs(ts RNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that ts RNAs are involved in neurological disorders and play a role in the pathogenesis of neurodegenerative disease. However, whether ts RNAs are involved in traumatic brain injury-induced secondary injury remains poorly understood. In this study, a mouse controlled cortical impact model of traumatic brain injury was established, and integrated ts RNA and messenger RNA(m RNA) transcriptome sequencing were used. The results revealed that 103 ts RNAs were differentially expressed in the mouse model of traumatic brain injury at 72 hours, of which 56 ts RNAs were upregulated and 47 ts RNAs were downregulated. Based on micro RNA-like seed matching and Pearson correlation analysis, 57 differentially expressed ts RNA-m RNA interaction pairs were identified, including 29 ts RNAs and 26 m RNAs. Moreover, Gene Ontology annotation of target genes revealed that the significantly enriched terms were primarily associated with inflammation and synaptic function. Collectively, our findings suggest that ts RNAs may be associated with traumatic brain injury-induced secondary brain injury, and are thus a potential therapeutic target for traumatic brain injury. The study was approved by the Beijing Neurosurgical Institute Animal Care and Use Committee(approval No. 20190411) on April 11, 2019.
基金This study was supported by the National Natural Science Foundation of China,No.81771327(to BYL)the Platform Construction of Basic Research and Clinical Translation of Nervous System Injury,China,No.PXM2020_026280_000002(to BYL)the Scientific Research and Cultivation Fund of the Beijing Neurosurgical Institute,China,No.2020002(to FN).
文摘Dexamethasone has been widely used after various neurosurgical procedures due to its anti-inflammatory property and the abilities to restore vascular permeability,inhibit free radicals,and reduce cerebrospinal fluid production.According to the latest guidelines for the treatment of traumatic brain injury in the United States,high-dose glucocorticoids cause neurological damage.To investigate the reason why high-dose glucocorticoids after traumatic brain injury exhibit harmful effect,rat controlled cortical impact models of traumatic brain injury were established.At 1 hour and 2 days after surgery,rat models were intraperitoneally administered dexamethasone 10 mg/kg.The results revealed that 31 proteins were significantly upregulated and 12 proteins were significantly downregulated in rat models of traumatic brain injury after dexamethasone treatment.The Ingenuity Pathway Analysis results showed that differentially expressed proteins were enriched in the mitochondrial dysfunction pathway and synaptogenesis signaling pathway.Western blot analysis and immunohistochemistry results showed that Ndufv2,Maob and Gria3 expression and positive cell count in the dexamethasone-treated group were significantly greater than those in the model group.These findings suggest that dexamethasone may promote a compensatory increase in complex I subunits(Ndufs2 and Ndufv2),increase the expression of mitochondrial enzyme Maob,and upregulate synaptic-transmission-related protein Gria3.These changes may be caused by nerve injury after traumatic brain injury treatment by dexamethasone.The study was approved by Institutional Ethics Committee of Beijing Neurosurgical Institute(approval No.201802001)on June 6,2018.
基金supported by the National Natural Science Foundation of China(Nos.11722546 and 11675226)the Talent Program of South China University of Technology(No.K5180470)
文摘The mechanism of multinucleon transfer reactions has been investigated within the dinuclear system model, in which the sequential nucleon transfer is described by solving a set of microscopically derived master equations. The transfer dynamics in the reaction of^(136)Xe+^(208)Pb near Coulomb barrier energies is thoroughly analyzed. It is found that the total kinetic energies of primary fragments are dissipated from the relative motion energy of two touching nuclei and exhibit a symmetric distribution along the fragment mass. The angular distribution of the projectile-like fragments moves forward with increasing beam energy. However, the target-like fragments exhibit an opposite trend. The shell effect is pronounced due to the fragment yields in multinucleon transfer reactions.
基金Project(51604309)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare IndustryProject(2015CX001)supported by the Innovation-driven Plan in Central South University,China
文摘Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate solution.The effects ofiron-containing phases on the transformation of sulfur-bearing ions(S2?,223S O?,23SO?and24SO?)in sodium aluminate solutionwere investigated.Fe,Fe2O3and Fe3O4barely react with23SO?and24SO?,but all of them,particularly Fe,can promote theconversion of223S O?to23SO?and S2?in sodium aluminate solution.Fe can convert to3Fe(OH)?in solution at elevatedtemperatures,and further react with S2?to form FeS2,but Fe2O3and Fe3O4have little influence on the reaction behavior of S2?insodium aluminate solution.Increasing temperature,duration,dosage of Fe,mole ratio of Na2Ok to Al2O3and caustic sodaconcentration are beneficial to the transformation of223S O?to23SO?and S2?.The results may contribute to the development oftechnologies for alleviating the equipment corrosion and reducing caustic consumption during the high-sulfur bauxite treatment bythe Bayer process.
基金This work was supported by the National Natural Science Foundation of China(Nos.12175072 and 11722546)the Talent Program of South China University of Technology.
文摘The fusion dynamics of the formation of super-heavy nuclei were investigated thoroughly within the din-uclear system model.The Monte Carlo approach was implemented in the nucleon transfer process to include all possible orientations,at which the dinuclear system is assumed to be formed at the touching configuration of dinuclear fragments.The production cross sections of superheavy nuclei Cn,Fl,Lv,Ts,and Og were calculated and compared with the available data from Dubna.The evaporation residue excitation functions in the channels of pure neutrons and charged particles were systematically analyzed.The combinations of 44 Sc,48;50 Ti,49;51 V,52;54 Cr,58;62 Fe,and 62;64 Ni bombarding the actinide nuclides 238 U,244 Pu,248 Cm,247;249 Bk,249;251 Cf,252 Es,and 243 Am were calculated to produce the superheavy elements with Z¼119?122.We obtained that the production cross sections sensitively depend on the neutron richness of the reaction system.The structure of the evaporation residue excitation function is related to the neutron separation energy and fission barrier of the compound nucleus.
基金supported by the National Natural Science Foundation of China(Nos.11722546 and 11675226)the Talent Program of South China University of Technology。
文摘Within the framework of the dinuclear system model,the multinucleon transfer dynamics for nearly symmetric nuclear collisions has been investigated.The reaction mechanism in the systems of 198Pt+198Pt and 204Hg+198Pt was investigated at beam energies around the Coulomb barrier.It was found that the isotopic yields are enhanced with increased incident energy in the domain of proton-rich nuclides.However,the production on the neutron-rich side weakly depends on the energy.The angular distribution with the beam energy was also analyzed in the multinucleon transfer reactions.Projectile-like fragments were produced toward the forward emission with increasing incident energy.The target-like fragments manifested the opposite trend in the transfer reactions.
基金financially supported by the National Nature Science Foundation of China (No. 51003060)the Distinguished Young Talents in Higher Education of Guangdong China (No. 2012LYM_0118)the Shenzhen Innovation and Technology Commission under the Strategic Emerging Industries Development Project (No. ZDSY20120612094418467)
文摘Electroless Cu plating was used for flake G powder and CNTs, Cu-G-CNTs （copper/graphite/carbon nanotubes） composites were manufactured by means of powder metallurgical method. The influences of CNTs on the mechanical properties, conductivity properties, friction, and wear performance of the composite were examined. The results indicate that adding a small amount of CNTs can improve comprehensive property of the composites, especially mechanical property. However, excessive CNT, which is easily winding reunion and grain boundary seg- regation, results in performances degradation.
基金funded by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31020302)the National Natural Science Foundation of China(31730104,31770425,32071495,32170515,32070453,and 32000317)Derek W.Dunn was supported by a Shaanxi Province Talents 100 Fellowships.
文摘Small and isolated populations face several intrinsic risks,such as genetic drift,inbreeding depression,and reduced gene fow.Thus,patterns of genetic diversity and differentiation have become an important focus of conservation genetics research.The golden snub-nosed monkey Rhinopithecus roxellana,an endangered species endemic to China,has experienced rapid reduction in population size and severe population fragmentation over the past few decades.We measured the patterns of genetic diversity and population differentiation using both neutral microsatellites and adaptive major histocompatibility complex(MHC)genes in 2 R.roxellana populations(DPY and GNG)distributed on the northern and southern slopes of the Qinling Mountains,respectively.Eight MHC-linked haplotypes formed by 5 DQA1 alleles,5 DQB1 alleles,5 DRB1 alleles,and 4 DRB2 alleles were detected in the 2 populations.The larger GNG population showed higher genetic variation for both MHC and microsatellites than the smaller DPY population,suggesting an effect of genetic drift on genetic variation.Genetic differentiation index(FST)outlier analyses,principal coordinate analysis(PCoA),and inferred population genetic structure showed lower genetic differentiation in the MHC variations than microsatellites,suggesting that pathogen-mediated balancing selection,rather than local adaptation,homogenized the MHC genes of both populations.This study indicates that both balancing selection and genetic drift may shape genetic variation and differentiation in small and fragmented populations.
基金supported by the National Natural Science Foundation of China(32070457,32200396,31730104)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31020302)+2 种基金The Biodiversity Survey and Assessment Project(2019HJ2096001006)Key Cultivation Research Project of Shaanxi Academy of Sciences(2022K-05)The American Society of Primatologists wild“Saving Primates Where They Live”Partnership Award.
文摘Infanticide,killing unweaned offspring in conspecifics,occurs widely among mammals,such as rodents,ungulates,and carnivores,especially in primates(Lukas and Huchard 2014).Such scenarios are often triggered by intruders that have replaced the former dominant males in nonhuman primates(Borries 1997).It has widely been viewed that infanticide is one of the solutions of sexually driven evolutionary selection:males kill infants to end lactational amenorrhea of the victim's mothers,forcing them to return to estrus and providing infanticidal males with the opportunities to sire their new offspring(Hrdy 1979).There is a broad spectrum regarding the patterns and mechanisms causing such events,referring to alternative breeding behaviors and mating systems-monogamy,polyandry,polygyny,and promiscuity(Qi et al.2020).
基金This work was supported by grants from National Natural Science Foundation of China(81471238,81771327)Construction of Central Nervous System Injury Basic Science and Clinical Translational Research Platform,Budget of Beijing Municipal Health Commission 2020(No.PXM2020_026280_000002).
文摘Traumatic brain injury(TBI),a growing public health problem,is a leading cause of death and disability worldwide,although its prevention measures and clinical cares are substantially improved.Increasing evidence shows that TBI may increase the risk of mood disorders and neurodegenerative diseases,including Alzheimer’s disease(AD).However,the complex relationship between TBI and AD remains elusive.Metabolic dysfunction has been the common pathology in both TBI and AD.On the one hand,TBI perturbs the glucose metabolism of the brain,and causes energy crisis and subsequent hyperglycolysis.On the other hand,glucose deprivation promotes amyloidogenesis viaβ-site APP cleaving enzyme-1 dependent mechanism,and triggers tau pathology and synaptic function.Recent findings suggest that TBI might facilitate Alzheimer’s pathogenesis by altering metabolism,which provides clues to metabolic link between TBI and AD.In this review,we will explore how TBI-induced metabolic changes contribute to the development of AD.
基金Project supported by the National Natural Science Foundation of China(NSFC)(51774155)Jiangxi Provincial Key Research and Development Program(20192BBE50028)the Doctoral Scientific Research Foundation of Jiangxi University of Science and Technology(jxxjbs17077)。
文摘SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of cobalt-induced SmF_(3)for preparing SmCo_(5)alloy is feasible.An alloy with 33.89 wt%samarium and a yield of 96.45%were achieved under the optimal conditions of 10%and 20%excess of SmF_(3)and calcium over the stoichiometry,respectively,and 1450℃for 4 min.The X-ray diffraction results show that the reduction products are SmCo_(5)alloy and CaF_(2).The scanning electron microscopy micrograph of the SmCo_(5)alloy ingot exhibits a distinct dendritic morphology composed of samarium and cobalt.The X-ray photoelectron spectroscopy shows that the atomic ratio of samarium to cobalt is approximately 1:5 and both elements demonstrate zero valency(Sm^(0),Co^(0)).The magnetic properties measurement of the SmCo_(5)alloy melt-spun ribbon shows the remanent magnetization B_r=0.59 T,intrinsic coercivity H_(Ci)=345.82 kA/m and maximum magnetic energy density(BH)_(max)=42.20 kJ/m^(3).These results may be helpful for the development of novel valence-variable rare-earth alloys.
基金Supported by the National Natural Science Foundation of China(11722546,11675226)the Talent Program of South China University of Technology(K5180470)
文摘The isospin effect in peripheral heavy-ion collisions was thoroughly investigated within the framework of the Lanzhou quantum molecular dynamics （LQMD） transport model. A coalescence approach was used to recognize the primary fragments formed in nucleus-nucleus collisions. described using the statistical code GEMINI. The production The secondary decay process of these fragments was mechanism and isospin effect of the projectile-like and target-like fragments were analyzed using the combined approach. It was found that the isospin migration from the high-isospin density to the low-density matter occurred in the neutron-rich nuclear reactions, i.e., ^48Ca＋^208Pb, ^86Kr＋^48SCa/^208Pb/^124Sn,^136Xe＋^208Pb, ^124Sn＋^124Sn, and ^136Xe＋^136Xe. A hard symmetry energy was available for creating the neutron-rich fragments, particularly in the medium-mass region. The isospin effect of the neutron-to- proton （n/p） ratio of the complex fragments was reduced when the secondary decay process was included. However, a soft symmetry energy enhanced the n/p ratio of the light particles, particularly at kinetic energies greater than 15 MeV/nucleon.
基金Project supported by the Cultivation Project of the State Key Laboratory of Green Development and High-value Utilization of Ionic Rare Earth Resources in Jiangxi Province(20194AFD44003)。
文摘Neodymium naphthenate-loaded organic phase stripping using sodium oxalate solution was studied to explore the feasibility of synchronous rare earth-loaded organic phase stripping,rare earth precipitation,and blank organic phase saponification.Experimental results show that loaded organic phase stripping,rare earth precipitation,and blank organic phase saponification can be realized simultaneously.When using 20% excess of sodium oxalate over the stoichiometry with the volume ratio of organic phase to aqueous phase of 1:1 at 25℃ for 40 min,the single stage stripping rate and saponification value are about 40% and 0.29 mol/L,respectively.After 16 stages of countercurrent continuous stripping,the stripping rate of neodymium can reach 99%,the saponification value is 0.42 mol/L,the Nd^(3+) concentration in saponified organic phase is less than 0.0020 mol/L,and the main phase in precipitation isNd_(2)(C2 O_(4))3·10 H_(2) O.Afterwards,this saponified organic phase can be used in the extraction of NdCl_(3) solution,and then the loaded organic phases(neodymium naphthenate) with 0.16 mol/L Nd^(3+) can be retrieved.The morphology,particle size distribution,and composition of theNd_(2)(C2 O_(4))3·10 H_(2) O products are similar to those of the current direct precipitation products.The neodymium oxide prepared by continuous calcination of neodymium oxalate meets the national standard of China(GB/T 5240-2015).These results prove the feasibility of stripping neodymium naphthenate-loaded organic phase by using sodium oxalate solution.Sodium oxalate can serve as a stripping agent,a saponifier,and a precipitator,thereby simplifying rare earth extraction and separation.This study provides theoretical and technical support for the development of a novel method for rare earth extraction and separation.
