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1.
J Neuroinflammation ; 20(1): 247, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880726

RESUMO

BACKGROUND: The astrocytes in the central nervous system (CNS) exhibit morphological and functional diversity in brain region-specific pattern. Functional alterations of reactive astrocytes are commonly present in human temporal lobe epilepsy (TLE) cases, meanwhile the neuroinflammation mediated by reactive astrocytes may advance the development of hippocampal epilepsy in animal models. Nuclear factor I-A (NFIA) may regulate astrocyte diversity in the adult brain. However, whether NFIA endows the astrocytes with regional specificity to be involved in epileptogenesis remains elusive. METHODS: Here, we utilize an interference RNA targeting NFIA to explore the characteristics of NFIA expression and its role in astrocyte reactivity in a 4-aminopyridine (4-AP)-induced seizure model in vivo and in vitro. Combined with the employment of a HA-tagged plasmid overexpressing NFIA, we further investigate the precise mechanisms how NIFA facilitates epileptogenesis. RESULTS: 4-AP-induced NFIA upregulation in hippocampal region is astrocyte-specific, and primarily promotes detrimental actions of reactive astrocyte. In line with this phenomenon, both NFIA and vanilloid transient receptor potential 4 (TRPV4) are upregulated in hippocampal astrocytes in human samples from the TLE surgical patients and mouse samples with intraperitoneal 4-AP. NFIA directly regulates mouse astrocytic TRPV4 expression while the quantity and the functional activity of TRPV4 are required for 4-AP-induced astrocyte reactivity and release of proinflammatory cytokines in the charge of NFIA upregulation. NFIA deficiency efficiently inhibits 4-AP-induced TRPV4 upregulation, weakens astrocytic calcium activity and specific astrocyte reactivity, thereby mitigating aberrant neuronal discharges and neuronal damage, and suppressing epileptic seizure. CONCLUSIONS: Our results uncover the critical role of NFIA in astrocyte reactivity and illustrate how epileptogenic brain injury initiates cell-specific signaling pathway to dictate the astrocyte responses.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Fatores de Transcrição NFI , Canais de Cátion TRPV , Animais , Humanos , Camundongos , 4-Aminopiridina/efeitos adversos , Astrócitos/metabolismo , Encéfalo/metabolismo , Sistema Nervoso Central/metabolismo , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Fatores de Transcrição NFI/genética , Fatores de Transcrição NFI/metabolismo , Canais de Cátion TRPV/metabolismo , Regulação para Cima
2.
FASEB J ; 35(2): e21330, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33417289

RESUMO

Epilepsy is a common brain disorder, repeated seizures of epilepsy may lead to a series of brain pathological changes such as neuronal or glial damage. However, whether circular RNAs are involved in neuronal injury during epilepsy is not fully understood. Here, we screened circIgf1r in the status epilepticus model through circRNA sequencing, and found that it was upregulated after the status epilepticus model through QPCR analysis. Astrocytes polarizing toward neurotoxic A1 phenotype and neurons loss were observed after status epilepticus. Through injecting circIgf1r siRNA into the lateral ventricle, it was found that knocking down circIgf1r in vivo would induce the polarization of astrocytes to phenotype A2 and reduce neuronal loss. The results in vitro further confirmed that inhibiting the expression of circIgf1r in astrocytes could protect neurons by converting reactive astrocytes from A1 to the protective A2. In addition, knocking down circIgf1r in astrocytes could functionally promote astrocyte autophagy and relieve the destruction of 4-AP-induced autophagy flux. In terms of mechanism, circIgf1r promoted the polarization of astrocytes to phenotype A1 by inhibiting autophagy. Taken together, our results reveal circIgf1r may serve as a potential target for the prevention and treatment of neuron damage after epilepsy.


Assuntos
Astrócitos/metabolismo , Epilepsia/genética , Inativação Gênica , RNA Circular/metabolismo , Animais , Astrócitos/citologia , Células Cultivadas , Epilepsia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurogênese , Neurônios/metabolismo , RNA Circular/genética , Receptor IGF Tipo 1/genética
3.
Intervirology ; 65(1): 17-28, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34438397

RESUMO

BACKGROUND: For foamy virus, the transactivator of spumaretrovirus (Tas) could bind directly to target DNA sequences termed as Tas responsive elements and trigger the viral internal promoter (IP) and long terminal repeat (LTR) promoters. The cellular endogenous factors also play an important role in viral gene expressions. We hypothesized that except the viral transcription factor Tas, the cellular endogenous factors also affect the viral gene expression. METHODS: The full length of the prototype foamy virus (PFV) genome (U21247) was used to predict the potential binding sites of the transcription factors by online software JASPAR (http://jaspar.genereg.net) and Softberry (http://linux1.softberry.com/berry.phtml?topic=index&group=programs&subgroup=promoter). The Dual-Luciferase® Reporter Assay System (Promega, USA) was used to confirm the relative luciferase activities of the test groups. The different representative activating agents or inhibitors of each canonical signal pathway were used to identify the impact of these pathways on PFV 5'LTR and IP promoters. RESULTS: The results showed different cellular endogenous factors might have respective effects on PFV 5'LTR and IP. It is worth mentioning that activator protein-1 and BCL2-associated athanogene 3, 2 kinds of vital proteins associated with NF-κB and PKC pathways, could activate the basal activity of 5'LTR and IP promoters but inhibit the Tas-regulated activity of both promoters. Furthermore, PFV Tas was identified to trigger the transcription of the NF-κB promoter. CONCLUSION: NF-κB had a negative effect on PFV 5'LTR and IP promoter activities, the PKC pathway might upregulate 5'LTR and IP promoter activities, and the JNK and NF-AT signal pathway could increase the Tas-regulated promoter activity of PFV 5'LTR. This study sheds light on the interaction between PFV and the host cell and may help utilize the viral promoters in retroviral vectors designed for gene transfer experiments.


Assuntos
Spumavirus , Linhagem Celular , Regiões Promotoras Genéticas , Spumavirus/genética , Sequências Repetidas Terminais/genética , Fatores de Transcrição
4.
Genomics ; 113(1 Pt 1): 11-19, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33249173

RESUMO

To explore potential critical genes and identify circular RNAs (circRNAs) that act as the competitive endogenous RNA (ceRNA) in a hypoxic pulmonary hypertension (HPH) rat model. Constructed rat model, and a bioinformatics method was used to analyse differentially expressed (DE) genes and construct a circRNA-miRNA-mRNA ceRNA regulatory network. Then, qRT-PCR was used to verify. The significant DEcircRNAs/DEmiRNAs/DEmRNAs was showed, and a ceRNA network with 8 DEcircRNAs, 9 DEmiRNAs and 46 DEmRNAs were constructed. The functional enrichment suggested the inflammatory response, NF-κB signalling, MAPK cascade and Toll-like receptor were associated with HPH. Further assessment confirmed that circ_002723, circ_008021, circ_016925 and circ_020581 could have a potential ceRNA mechanism by sponging miR-23a or miR-21 to control downstream target gene and be involved in the pathophysiology of HPH. The qRT-PCR validation results were consistent with the RNA-Seq results. This study revealed potentially important genes, pathways and ceRNA regulatory networks in HPH.


Assuntos
Redes Reguladoras de Genes , Hipertensão Pulmonar/genética , Hipóxia/genética , Mapas de Interação de Proteínas , RNA Circular/metabolismo , Animais , Hipertensão Pulmonar/metabolismo , Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , NF-kappa B/metabolismo , RNA Circular/genética , Ratos , Ratos Sprague-Dawley , Receptores Toll-Like/metabolismo , Transcriptoma
5.
J Phys Ther Sci ; 32(6): 359-364, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32581426

RESUMO

[Purpose] This study aimed to explore whether trunk kinesiology taping (KT) can improve trunk function, mobility, and balance in post-stroke patients with hemiparesis. [Participants and Methods] We conducted a single-group pre-post design pilot feasibility study. Thirteen individuals with post-stroke hemiplegia were recruited for this study. All patients received therapeutic trunk KT on the skin, representing the direction of fibres of the trunk muscles underneath. We used the Trunk Impairment Scale (TIS) and Trunk Control Test (TCT) to measure trunk function, Fugl-Meyer assessment (FMA) for balance, limits of stability (LOS) to evaluate balance, and the modified Rivermead mobility index (MRMI) to assess mobility in post-stroke patients. All measures were assessed before and immediately after the intervention. [Results] No adverse effects were found and all patients completed the trial. Compared to the baseline, TIS scores were significantly increased after KT, whereas no changes in TCT score were detected. The directional control of LOS was significantly improved, while no significant changes were seen in the other parameters of LOS, FMA-balance, and MRMI scores. [Conclusion] The results of this investigation show that trunk KT has immediate effects that improve certain trunk functional and balance parameters in stroke patients.

6.
J Neuroinflammation ; 16(1): 114, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142341

RESUMO

BACKGROUND: Hypoxic-ischemic encephalopathy (HIE) is a serious birth complication with high incidence in both advanced and developing countries. Children surviving from HIE often have severe long-term sequela including cerebral palsy, epilepsy, and cognitive disabilities. The severity of HIE in infants is tightly associated with increased IL-1ß expression and astrocyte activation which was regulated by transient receptor potential vanilloid 1 (TRPV1), a non-selective cation channel in the TRP family. METHODS: Neonatal hypoxic ischemia (HI) and oxygen-glucose deprivation (OGD) were used to simulate HIE in vivo and in vitro. Primarily cultured astrocytes were used for investigating the expression of glial fibrillary acidic protein (GFAP), IL-1ß, Janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3), and activation of the nucleotide-binding, oligomerization domain (NOD)-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome by using Western blot, q-PCR, and immunofluorescence. Brain atrophy, infarct size, and neurobehavioral disorders were evaluated by Nissl staining, 2,3,5-triphenyltetrazolium chloride monohydrate (TTC) staining and neurobehavioral tests (geotaxis reflex, cliff aversion reaction, and grip test) individually. RESULTS: Astrocytes were overactivated after neonatal HI and OGD challenge. The number of activated astrocytes, the expression level of IL-1ß, brain atrophy, and shrinking infarct size were all downregulated in TRPV1 KO mice. TRPV1 deficiency in astrocytes attenuated the expression of GFAP and IL-1ß by reducing phosphorylation of JAK2 and STAT3. Meanwhile, IL-1ß release was significantly reduced in TRPV1 deficiency astrocytes by inhibiting activation of NLRP3 inflammasome. Additionally, neonatal HI-induced neurobehavioral disorders were significantly improved in the TRPV1 KO mice. CONCLUSIONS: TRPV1 promotes activation of astrocytes and release of astrocyte-derived IL-1ß mainly via JAK2-STAT3 signaling and activation of the NLRP3 inflammasome. Our findings provide mechanistic insights into TRPV1-mediated brain damage and neurobehavioral disorders caused by neonatal HI and potentially identify astrocytic TRPV1 as a novel therapeutic target for treating HIE in the subacute stages (24 h).


Assuntos
Astrócitos/metabolismo , Encéfalo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Interleucina-1beta/metabolismo , Canais de Cátion TRPV/deficiência , Animais , Astrócitos/patologia , Encéfalo/patologia , Células Cultivadas , Feminino , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canais de Cátion TRPV/genética
7.
J Neuroinflammation ; 16(1): 214, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722723

RESUMO

BACKGROUND: Neonatal hypoxic-ischemic brain damage (HIBD), a leading cause of neonatal mortality, has intractable sequela such as epilepsy that seriously affected the life quality of HIBD survivors. We have previously shown that ion channel dysfunction in the central nervous system played an important role in the process of HIBD-induced epilepsy. Therefore, we continued to validate the underlying mechanisms of TRPV1 as a potential target for epilepsy. METHODS: Neonatal hypoxic ischemia and oxygen-glucose deprivation (OGD) were used to simulate HIBD in vivo and in vitro. Primarily cultured astrocytes were used to assess the expression of TRPV1, glial fibrillary acidic protein (GFAP), cytoskeletal rearrangement, and inflammatory cytokines by using Western blot, q-PCR, and immunofluorescence. Furthermore, brain electrical activity in freely moving mice was recorded by electroencephalography (EEG). TRPV1 current and neuronal excitability were detected by whole-cell patch clamp. RESULTS: Astrocytic TRPV1 translocated to the membrane after OGD. Mechanistically, astrocytic TRPV1 activation increased the inflow of Ca2+, which promoted G-actin polymerized to F-actin, thus promoted astrocyte migration after OGD. Moreover, astrocytic TRPV1 deficiency decreased the production and release of pro-inflammatory cytokines (TNF, IL-6, IL-1ß, and iNOS) after OGD. It could also dramatically attenuate neuronal excitability after OGD and brain electrical activity in HIBD mice. Behavioral testing for seizures after HIBD revealed that TRPV1 knockout mice demonstrated prolonged onset latency, shortened duration, and decreased seizure severity when compared with wild-type mice. CONCLUSIONS: Collectively, TRPV1 promoted astrocyte migration thus helped the infiltration of pro-inflammatory cytokines (TNF, IL-1ß, IL-6, and iNOS) from astrocytes into the vicinity of neurons to promote epilepsy. Our study provides a strong rationale for astrocytic TRPV1 to be a therapeutic target for anti-epileptogenesis after HIBD.


Assuntos
Astrócitos/metabolismo , Epilepsia/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Inflamação/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Encéfalo/metabolismo , Movimento Celular/fisiologia , Citocinas/metabolismo , Epilepsia/etiologia , Hipóxia-Isquemia Encefálica/complicações , Camundongos , Camundongos Knockout , Neurônios/metabolismo
8.
J Neuroinflammation ; 15(1): 186, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925377

RESUMO

BACKGROUND: Neonatal hypoxic-ischemic brain damage, characterized by tissue loss and neurologic dysfunction, is a leading cause of mortality and a devastating disease of the central nervous system. We have previously shown that vitexin has been attributed various medicinal properties and has been demonstrated to have neuroprotective roles in neonatal brain injury models. In the present study, we continued to reinforce and validate the basic understanding of vitexin (45 mg/kg) as a potential treatment for epilepsy and explored its possible underlying mechanisms. METHODS: P7 Sprague-Dawley (SD) rats that underwent right common carotid artery ligation and rat brain microvascular endothelial cells (RBMECs) were used for the assessment of Na+-K+-Cl- co-transporter1 (NKCC1) expression, BBB permeability, cytokine expression, and neutrophil infiltration by western blot, q-PCR, flow cytometry (FCM), and immunofluorescence respectively. Furthermore, brain electrical activity in freely moving rats was recorded by electroencephalography (EEG). RESULTS: Our data showed that NKCC1 expression was attenuated in vitexin-treated rats compared to the expression in the HI group in vivo. Oxygen glucose deprivation/reoxygenation (OGD) was performed on RBMECs to explore the role of NKCC1 and F-actin in cytoskeleton formation with confocal microscopy, N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide, and FCM. Concomitantly, treatment with vitexin effectively alleviated OGD-induced NKCC1 expression, which downregulated F-actin expression in RBMECs. In addition, vitexin significantly ameliorated BBB leakage and rescued the expression of tight junction-related protein ZO-1. Furthermore, inflammatory cytokine and neutrophil infiltration were concurrently and progressively downregulated with decreasing BBB permeability in rats. Vitexin also significantly suppressed brain electrical activity in neonatal rats. CONCLUSIONS: Taken together, these results confirmed that vitexin effectively alleviates epilepsy susceptibility through inhibition of inflammation along with improved BBB integrity. Our study provides a strong rationale for the further development of vitexin as a promising therapeutic candidate treatment for epilepsy in the immature brain.


Assuntos
Anticonvulsivantes/uso terapêutico , Apigenina/uso terapêutico , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Hipóxia-Isquemia Encefálica/complicações , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Animais , Animais Recém-Nascidos , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Cloretos/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/deficiência , Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/metabolismo , Interleucina-3/genética , Interleucina-3/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Membro 2 da Família 12 de Carreador de Soluto/genética , Proteína da Zônula de Oclusão-1/metabolismo
9.
Brain Behav Immun ; 48: 68-77, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25801060

RESUMO

Febrile seizure (FS) is the most common seizure disorder in children, and children with FS are regarded as a high risk for the eventual development of epilepsy. Brain inflammation may be implicated in the mechanism of FS. Transient receptor potential vanilloid 1 (TRPV1) is believed to act as a monitor and regulator of body temperature. The role of inflammation in synaptic plasticity mediation indicates that TRPV1 is relevant to several nervous system diseases, such as epilepsy. Here, we report a critical role for TRPV1 in a febrile seizure mouse model and reveal increased levels of pro-inflammatory factors in the immature brain. Animals were subjected to hyperthermia for 30 min, which generates seizures lasting approximately 20 min, and then were used for experiments. To invoke frequently repetitive febrile seizures, mice are exposed to hyperthermia for three times daily at an interval of 4h between every time induced seizure, and a total of 4 days to induce. Behavioral testing for febrile seizures revealed that a TRPV1 knock-out mouse model demonstrated a prolonged onset latency and a shortened duration and seizure grade of febrile seizure when compared with wild type (WT) mice. The expression levels of both TRPV1 mRNA and protein increased after a hyperthermia-induced febrile seizure in WT mice. Notably, TRPV1 activation resulted in a significant elevation in the expression of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α and HMGB1) in the hippocampus and cortex. These data indicate that the reduction of TRPV1 expression parallels a decreased susceptibility to febrile seizures. Thus, preventative strategies might be developed for use during febrile seizures.


Assuntos
Encéfalo/metabolismo , Citocinas/metabolismo , Hipertermia Induzida , Convulsões Febris/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Encéfalo/imunologia , Linhagem Celular , Modelos Animais de Doenças , Hipocampo/imunologia , Hipocampo/metabolismo , Camundongos , Camundongos Knockout , Convulsões Febris/imunologia , Canais de Cátion TRPV/genética
10.
Epilepsy Behav ; 31: 276-80, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24269027

RESUMO

This study was designed to investigate the role of experimental febrile seizures in the induction of generalized clonic seizures and the involvement of heat-sensitive channel TRPV1. Pentylenetetrazol-induced clonic seizure was used as the seizure model, and Trpv1 gene knock-out and wild-type C57/BL6 mice were used as experimental subjects. Electroencephalograph and seizure behavior were recorded for the evaluation of the severity of seizures. Increased frequency of the experimental febrile seizures facilitated PTZ-induced generalized clonic seizures. Trpv1 gene deficiency decreased the properties of generalized clonic seizure. The intensity of experimental febrile seizures reduced the threshold to generalized clonic seizure, and Trpv1 gene deficiency decreased the susceptibility to PTZ-induced seizures following early-life hyperthermia challenges in mice.


Assuntos
Convulsivantes/toxicidade , Hipertermia Induzida , Pentilenotetrazol/toxicidade , Convulsões Febris/induzido quimicamente , Convulsões Febris/genética , Canais de Cátion TRPV/metabolismo , Análise de Variância , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroencefalografia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canais de Cátion TRPV/deficiência , Fatores de Tempo
11.
J Biol Chem ; 287(35): 29479-94, 2012 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-22761436

RESUMO

The voltage-gated Kv1.3 K(+) channel in effector memory T cells serves as a new therapeutic target for multiple sclerosis. In our previous studies, the novel peptide ADWX-1 was designed and synthesized as a specific Kv1.3 blocker. However, it is unclear if and how ADWX-1 alleviates experimental autoimmune encephalomyelitis, a model for multiple sclerosis. In this study, the administration of ADWX-1 significantly ameliorated the rat experimental autoimmune encephalomyelitis model by selectively inhibiting CD4(+)CCR7(-) phenotype effector memory T cell activation. In contrast, the Kv1.3-specific peptide had little effect on CD4(+)CCR7(+) cells, thereby limiting side effects. Furthermore, we determined that ADWX-1 is involved in the regulation of NF-κB signaling through upstream protein kinase C-θ (PKCθ) in the IL-2 pathway of CD4(+)CCR7(-) cells. The elevated expression of Kv1.3 mRNA and protein in activated CD4(+)CCR7(-) cells was reduced by ADWX-1 engagement; however, an apparent alteration in CD4(+)CCR7(+) cells was not observed. Moreover, the selective regulation of the Kv1.3 channel gene expression pattern by ADWX-1 provided a further and sustained inhibition of the CD4(+)CCR7(-) phenotype, which depends on the activity of Kv1.3 to modulate its activation signal. In addition, ADWX-1 mediated the activation of differentiated Th17 cells through the CCR7(-) phenotype. The efficacy of ADWX-1 is supported by multiple functions, which are based on a Kv1.3(high) CD4(+)CCR7(-) T cell selectivity through two different pathways, including the classic channel activity-associated IL-2 pathway and the new Kv1.3 channel gene expression pathway.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Memória Imunológica/efeitos dos fármacos , Canal de Potássio Kv1.3/antagonistas & inibidores , Esclerose Múltipla/tratamento farmacológico , Peptídeos/farmacologia , Receptores CCR7 , Animais , Encefalomielite Autoimune Experimental/imunologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Interleucina-2/imunologia , Células Jurkat , Canal de Potássio Kv1.3/imunologia , Esclerose Múltipla/imunologia , RNA Mensageiro/imunologia , Ratos , Ratos Sprague-Dawley
12.
Epilepsia ; 54(7): 1223-31, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23815572

RESUMO

PURPOSE: Cerebral hypoxia is a major cause of neonatal seizures, and can lead to epilepsy. Pathologic anatomic and physiologic changes in the dentate gyrus have been associated with epileptogenesis in many experimental models, as this region is widely believed to gate the propagation of limbic seizures. However, the consequences of hypoxia-induced seizures for the immature dentate gyrus have not been extensively examined. METHODS: Seizures were induced by global hypoxia (5-7% O2 for 15 min) in rat pups on postnatal day 10. Whole-cell voltage-clamp recordings were used to examine A-type potassium currents (IA ) in dentate granule cells in hippocampal slices obtained 1-17 days after hypoxia treatment. KEY FINDINGS: Seizure-inducing hypoxia resulted in decreased maximum IA amplitude in dentate granule cells recorded within the first week but not at later times after hypoxia treatment. The decreased IA amplitude was not associated with changes in the voltage-dependence of activation or inactivation removal, or in sensitivity to inhibition by 4-aminopyridine (4-AP). However, consistent with the role of IA in shaping firing patterns, we observed in the hypoxia group a significantly decreased latency to first spike with depolarizing current injection from hyperpolarized potentials. These differences were not associated with changes in resting membrane potential or input resistance, and were eliminated by application of 10 m 4-AP. SIGNIFICANCE: Given the role of IA to slow action potential firing, decreased IA could contribute to long-term hippocampal pathology after neonatal seizure-inducing hypoxia by increasing dentate granule cell excitability during a critical window of activity-dependent hippocampal maturation.


Assuntos
Hipocampo/patologia , Hipóxia/complicações , Neurônios/fisiologia , Canais de Potássio/fisiologia , Convulsões/etiologia , Convulsões/patologia , 4-Aminopiridina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Animais Recém-Nascidos , Biofísica , Modelos Animais de Doenças , Estimulação Elétrica/efeitos adversos , Técnicas In Vitro , Masculino , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/efeitos dos fármacos , Ratos , Ratos Long-Evans
13.
Materials (Basel) ; 16(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37763400

RESUMO

By experimental methods, 26 specimens were designed to conduct elastic and elastic-plastic buckling tests on cylindrical shells containing cracks. This study discusses the influence of factors such as the length-diameter ratio, the diameter-thickness ratio, the crack length, the inclination of the crack, etc., on the buckling load. Additionally, finite element models were established to compare with experimental results. For the PMMA cylindrical shell, the results showed that as the length-diameter ratio of the cylindrical shell increased, the buckling load first decreased and then increased. For the 6063 aluminum alloy cylindrical shell, with increasing length-diameter ratio, diameter-thickness ratio, and crack length of the cylindrical shell, the buckling load decreased accordingly. However, concerning the crack inclination, as the crack inclination increased, the buckling load increased accordingly. This indicates that the larger the crack inclination, the higher the load capacity of the cylindrical shell containing cracks. Through finite element simulations of cylindrical shells with cracks, it was found that through compressive mechanical properties, both elastic and elastic-plastic buckling loads yielded results that are closer to the experimental results. Additionally, the inclusion of contact effects in numerical simulations further improved the agreement with the experimental results, and the variation trend of the buckling load in the finite element simulation was consistent with the experimental results. The research findings provide valuable references for the assessment of load capacity in structures containing cracks.

14.
Acta Virol ; 56(4): 283-91, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23237084

RESUMO

One of the most fascinating findings in retrovirology is the construction of viral vectors based on foamy viruses (FVs) for gene therapy. The envelope glycoprotein (Env), one of the structural proteins of FV, is an important antigen in the immunoassays, as it is highly specific. To compare the characteristics of all 15 available FV Envs, the phylogenesis, hydrophobicity, modifications, and conserved motifs were analyzed based on the Env sequences. Meanwhile, the secondary structures of transmembrane (TM) domains of FV Envs were predicted. The results of phylogenetic analyses based on Envs indicated that the foamy viruses from different hosts could form three groups. The hydrophobicity analysis revealed that FV Envs had two prominent hydrophobic regions, which was similar to other retroviruses. Though the glycosylation, ubiquitination, and the secondary structures of TM domains of FV Envs were in line with other retroviruses, the roles were distinctly different. Interestingly, the analyses of conserved motifs suggested that FV Envs possessed several specific functional motifs.


Assuntos
Infecções por Retroviridae/veterinária , Infecções por Retroviridae/virologia , Spumavirus/genética , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Filogenia , Conformação Proteica , Alinhamento de Sequência , Spumavirus/química , Spumavirus/classificação , Proteínas do Envelope Viral/metabolismo
15.
Materials (Basel) ; 16(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614703

RESUMO

Based on fracture mechanics theory, a finite element method was used to determine the stress intensity factors of the inclined crack on the inner surface of the pipe under axial compression load and external pressure. The effects of different influencing factors on the stress intensity factor along the crack front considering crack closure were systematically explored, which were different to those under internal pressure. The effects of high aspect ratio on KII, the crack inclination asymmetry caused by curvature and the effects of the friction coefficient on the stress intensity factors of the pipe with an inclined inner surface crack under axial compression load and external pressure were explored in this paper. To be fit for defect assessment, the solutions for stress intensity factors KII and KIII were derived, and new correction factors fθ and fµ were proposed in the empirical solutions to accommodate the crack inclination asymmetry and the friction coefficient, respectively.

16.
Front Immunol ; 13: 766200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237257

RESUMO

Asparaginase/pegaspargase containing regimens combined with radiotherapy are highly effective and considered the cornerstone of localized Natural killer/T-cell lymphoma (NKTL) treatment. However, these chemotherapy regimens inevitably cause relatively high incidence of treatment-related adverse events (TRAEs). Herein we retrospectively evaluated the efficacy and safety of the combined regimen of anti-PD-1 antibody, anlotinib and pegaspargase "sandwich" with radiotherapy in localized NKTL. Anti-PD-1 antibody and pegaspargase at 2500 U/m2 were administered on day 1, while anlotinib (12 mg once a day) was orally administered on days 1-14. The treatment was repeated every 3 weeks. All the eight patients included received 3 cycles of the regimen followed by radiotherapy and an additional 3 cycles. The overall response rate was 100%, and the complete response rate was 87.5%. With a median follow-up time of 35.5 months (range, 34.03-40.90 months), median PFS and OS times were not reached. The 3-year PFS and OS rates were 100% and 100%, respectively. All patients were alive at the last follow-up. No treatment-related death and no grade 4 TRAE was reported. No grade 3/4 hematological toxicity was detected, and half of the patients didn't report any hematological toxicity. This study indicates that anti-PD-1 antibody combined with anlotinib and pegaspargase is a promising chemoradiotherapy regimen for localized NTKL, with mild toxicity and good tolerance.


Assuntos
Asparaginase , Linfoma Extranodal de Células T-NK , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Asparaginase/uso terapêutico , Desoxicitidina/uso terapêutico , Humanos , Indóis , Células Matadoras Naturais/patologia , Linfoma Extranodal de Células T-NK/tratamento farmacológico , Linfoma Extranodal de Células T-NK/radioterapia , Polietilenoglicóis , Quinolinas , Estudos Retrospectivos
17.
Neurotherapeutics ; 19(2): 660-681, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35182379

RESUMO

Astrocytes are critical regulators of the immune/inflammatory response in several human central nervous system (CNS) diseases. Emerging evidence suggests that dysfunctional astrocytes are crucial players in seizures. The objective of this study was to investigate the role of transient receptor potential vanilloid 4 (TRPV4) in 4-aminopyridine (4-AP)-induced seizures and the underlying mechanism. We also provide evidence for the role of Yes-associated protein (YAP) in seizures. 4-AP was administered to mice or primary cultured astrocytes. YAP-specific small interfering RNA (siRNA) was administered to primary cultured astrocytes. Mouse brain tissue and surgical specimens from epileptic patient brains were examined, and the results showed that TRPV4 was upregulated, while astrocytes were activated and polarized to the A1 phenotype. The levels of glial fibrillary acidic protein (GFAP), cytokine production, YAP, signal transducer activator of transcription 3 (STAT3), intracellular Ca2+([Ca2+]i) and the third component of complement (C3) were increased in 4-AP-induced mice and astrocytes. Perturbations in the immune microenvironment in the brain were balanced by TRPV4 inhibition or the manipulation of [Ca2+]i in astrocytes. Knocking down YAP with siRNA significantly inhibited 4-AP-induced pathological changes in astrocytes. Our study demonstrated that astrocytic TRPV4 activation promoted neuroinflammation through the TRPV4/Ca2+/YAP/STAT3 signaling pathway in mice with seizures. Astrocyte TRPV4 inhibition attenuated neuroinflammation, reduced neuronal injury, and improved neurobehavioral function. Targeting astrocytic TRPV4 activation may provide a promising therapeutic approach for managing epilepsy.


Assuntos
Astrócitos , Convulsões , Canais de Cátion TRPV , Animais , Astrócitos/metabolismo , Humanos , Camundongos , Neurônios/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Convulsões/induzido quimicamente , Convulsões/genética , Convulsões/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo
18.
Arthropod Struct Dev ; 61: 101030, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33578074

RESUMO

The morphology and ultrastructure of the compound eye of the predatory bug, Montandoniola moraguesi (Puton, 1986) was investigated using scanning and transmission electron microscopy. Its compound eyes, which contain ∼195 ommatidia per eye, have the following characteristics: each ommatidium possesses a laminated corneal lens measuring ∼9 µm in diameter and ∼7 µm in thickness, a tetrapartite eucone crystalline cone, which is approximately 5.5 µm long, like a dumbbell with the distal end larger than the proximal end, eight clustered retinula cells ∼25.6 µm in length, two primary pigment cells and eight secondary primary pigment cells. The rhabdomeres of the eight retinula cells form a circular, tiered rhabdom of two elongated and six peripheral retinula cells. The rhabdomeres of cells R7 and R8 are distributed along the basolateral surface of the cone and form a centrally-fused rhabdom that spans nearly the full length of the ommatidium. The microvilli of the peripheral rhabdom (R1-R6) are radially arranged and form a bilobed, V-like shape in the central rhabdom. Based on the similarity of the compound eye of M. moraguesi to the eyes of other predatory insect species, the evolution and function of eyes in predators are briefly discussed.


Assuntos
Heterópteros , Animais , Olho Composto de Artrópodes/ultraestrutura , Heterópteros/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
19.
J Cancer ; 12(7): 2059-2064, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33754004

RESUMO

Purpose: Diffuse large B cell lymphoma (DLBCL) with MYC rearrangement or double expression of MYC and BCL-2 (DE DLBCL) has a relatively poor prognosis and does not respond well to standard R-CHOP. In the current study, we aimed to investigate the efficacy and safety of R-split-EPOCH plus high dose methotrexate (HD-MTX) in the particular patient population. Methods: A total of 28 patients diagnosed with DE DLBCL or DLBCL with MYC rearrangement between January 2015 and December 2018 were included and retrospectively analyzed. All the participants underwent R-split-EPOCH plus HD-MTX as introduction therapy, with split infusion of etoposide, doxorubicin, and vincristine for 48 hours on D1-2 and D10-11, respectively. Results: The overall objective response (ORR) rate was 100%, with 24 (85.7%) complete response (CR) and 4 (14.3%) partial response (PR). The CR rate was 76.9% and 93.3% for DLBCL patients with MYC rearrangement and DE DLBCL patients, respectively. The 1- and 3-year PFS rate was 100% and 74.9%, respectively. The 1- and 3-year OS rate was 100% and 92.9%, respectively. Grade 3/4 non-hematological toxicity and grade 3/4 hematological toxicity occurred in 50% and 85.7% of patients, respectively. No treatment-related death was reported. Conclusions: R-split-EPOCH plus HD-MTX regimen is an effective and feasible treatment option for DE DLBCL and DLBCL with MYC rearrangement.

20.
Neurosci Bull ; 37(10): 1427-1440, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34309810

RESUMO

Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures. Recent studies have shown that complement component 3 (C3) aggravate the neuronal injury in epilepsy. And our previous studies revealed that TRPV1 (transient receptor potential vanilloid type 1) is involved in epilepsy. Whether complement C3 regulation of neuronal injury is related to the activation of TRPV1 during epilepsy is not fully understood. We found that in a mouse model of status epilepticus (SE), complement C3 derived from astrocytes was increased and aggravated neuronal injury, and that TRPV1-knockout rescued neurons from the injury induced by complement C3. Circular RNAs are abundant in the brain, and the reduction of circRad52 caused by complement C3 promoted the expression of TRPV1 and exacerbated neuronal injury. Mechanistically, disorders of neuron-glia interaction mediated by the C3-TRPV1 signaling pathway may be important for the induction of neuronal injury. This study provides support for the hypothesis that the C3-TRPV1 pathway is involved in the prevention and treatment of neuronal injury and cognitive disorders.


Assuntos
Complemento C3 , Epilepsia , Neurônios/patologia , Estado Epiléptico , Canais de Cátion TRPV , Animais , Astrócitos/metabolismo , Complemento C3/metabolismo , Camundongos , Canais de Cátion TRPV/metabolismo
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