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1.
Small ; : e2312135, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501794

RESUMO

Carbon fiber (CF) is a potential microwave absorption (MA) material due to the strong dielectric loss. Nevertheless, owing to the high conductivity, poor impedance matching of carbon-based  materials results in limited MA performance. How to solve this problem and achieve excellent MA performance remains a principal challenge. Herein, taking full advantage of CF and excellent impedance matching of bimetallic metal-organic frameworks (MOF) derivatives layer, an excellent microwave absorber based on micron-scale 1D CF and NiCoMOF (CF@NiCoMOF-800) is developed. After adjusting the oxygen vacancies of the bimetallic MOF, the resultant microwave absorber presented excellent MA properties including the minimum reflection loss (RLmin ) of -80.63 dB and wide effective absorption bandwidth (EAB) of 8.01 GHz when its mass percent is only 5 wt.% and the thickness is 2.59 mm. Simultaneously, the mechanical properties of the epoxy resin (EP)-based coating with this microwave absorber are effectively improved. The hardness (H), elastic modulus (E), bending strength, and compressive strength of CF@NiCoMOF-800/EP coating are 334 MPa, 5.56 GPa, 82.2 MPa, and 135.8 MPa, which is 38%, 15%, 106% and 53% higher than EP coating. This work provides a promising solution for carbon materials achieving excellent MA properties and mechanical properties.

2.
Basic Res Cardiol ; 119(1): 75-91, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38172251

RESUMO

Mast cells (MCs) are important intermediates between the nervous and immune systems. The cardiac autonomic nervous system (CANS) crucially modulates cardiac electrophysiology and arrhythmogenesis, but whether and how MC-CANS neuroimmune interaction influences arrhythmia remain unclear. Our clinical data showed a close relationship between serum levels of MC markers and CANS activity, and then we use mast cell stabilizers (MCSs) to alter this MC-CANS communication. MCSs, which are well-known anti-allergic agents, could reduce the risk of ventricular arrhythmia (VA) after myocardial infarction (MI). RNA-sequencing (RNA-seq) analysis to investigate the underlying mechanism by which MCSs could affect the left stellate ganglion (LSG), a key therapeutic target for modulating CANS, showed that the IL-6 and γ-aminobutyric acid (GABA)-ergic system may be involved in this process. Our findings demonstrated that MCSs reduce VA risk along with revealing the potential underlying antiarrhythmic mechanisms.


Assuntos
Antialérgicos , Estabilizadores de Mastócitos , Humanos , Neuroimunomodulação , Arritmias Cardíacas/prevenção & controle , Coração
3.
J Mol Cell Cardiol ; 184: 37-47, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37783395

RESUMO

Psychological stress has been recognized as a contributing factor to worsened prognosis in patients with cardiac failure following myocardial infarction (MI). Although the ventrolateral part of the ventromedial hypothalamus (VMHVL) has been implicated in emotional distress, its involvement in post-MI cardiac dysfunction remains largely unexplored. This study was designed to investigate the effect of the VMHVL activation in the MI rat model and its underlying mechanisms. Our findings demonstrate that activation of VMHVL neurons enhances the activity of the cardiac sympathetic nervous system through the paraventricular nucleus (PVN) and superior cervical ganglion (SCG). This activation leads to an elevation in catecholamine levels, which subsequently modulates myosin function and triggers the release of anti-inflammatory factors, to exacerbate the post-MI cardiac prognosis. The denervation of the superior cervical ganglion (SGN) effectively blocked the cardiac sympathetic effects induced by the VMHVL activation, and ameliorated the cardia fibrosis and dysfunction. Therefore, our study identified the role of the "VMHVL-PVN-SCG" sympathetic pathway in the post-MI heart, and proposed SGN as a promising strategy in mitigating cardiac prognosis in stressful rats.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Ratos , Animais , Infarto do Miocárdio/metabolismo , Coração , Sistema Nervoso Simpático/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo
4.
J Virol ; 96(16): e0079122, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35913215

RESUMO

Spring viremia of carp virus (SVCV) is a severe infectious pathogen that causes high rates of mortality in cyprinids and other fish species. Despite numerous investigations of SVCV infection, the underlying molecular mechanisms remain poorly understood. In this study, we found that the SVCV matrix protein (SVCV-M) played an inhibitory role in the host interferon (IFN) response by targeting the MAVS/TRAF3 signaling axis, thereby uncovering a previously unrecognized mechanism of SVCV escape from host innate antiviral immunity. Mechanistically, SVCV-M was located at the mitochondria independent of MAVS, which allowed SVCV-M to build an arena for competition with the MAVS platform. A microscale thermophoresis assay showed that SVCV-M had a high affinity for TRAF3, as indicated by a lower equilibrium dissociation constant (KD) value than that of MAVS with TRAF3. Therefore, the association of MAVS with TRAF3 was competitively impaired by SVCV-M in a dose-dependent manner. Accordingly, SVCV-M showed a potent ability to inhibit the K63-linked polyubiquitination of TRAF3. This inhibition was accompanied by the impairment of the IFN response, as shown by the marked decline in IFN-φ1-promoter (pro) luciferase reporter activity. By constructing truncated TRAF3 and SVCV-M proteins, the RING finger, zinc finger, and coiled-coil domains of TRAF3 and the hydrophobic-pocket-like structure formed by the α2-, α3-, and α4-helices of SVCV-M may be the major target and antagonistic modules responsible for the protein-protein interaction between the TRAF3 and SVCV-M proteins. These findings highlighted the intervention of SVCV-M in host innate immunity, thereby providing new insights into the extensive participation of viral matrix proteins in multiple biological activities. IMPORTANCE The matrix protein of SVCV (SVCV-M) is an indispensable structural element for nucleocapsid condensation and virion formation during viral morphogenesis, and it connects the core nucleocapsid particle to the outer membrane within the mature virus. Previous studies have emphasized the architectural role of SVCV-M in viral construction; however, the potential nonstructural functions of SVCV-M in viral replication and virus-host interactions remain poorly understood. In this study, we identified the inhibitory role of the SVCV-M protein in host IFN production by competitively recruiting TRAF3 from the MAVS signaling complex and impairing TRAF3 activation via inhibition of K63-linked polyubiquitination. This finding provided new insights into the regulatory role of SVCV-M in host innate immunity, which highlighted the broader functionality of rhabdovirus matrix protein apart from being a structural protein. This study also revealed a previously unrecognized mechanism underlying SVCV immune evasion by inhibiting the IFN response by targeting the MAVS/TRAF3 signaling axis.


Assuntos
Carpas , Infecções por Rhabdoviridae/veterinária , Rhabdoviridae/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Imunidade Inata , Interferons/metabolismo , Infecções por Rhabdoviridae/imunologia , Fator 3 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/metabolismo , Proteínas da Matriz Viral/metabolismo , Viremia/veterinária
5.
Inflamm Res ; 72(5): 901-913, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933018

RESUMO

BACKGROUND AND OBJECTIVE: Emotional stress substantially increases the risk of ischemic cardiovascular diseases. Previous study indicates that sympathetic outflow is increased under emotional stress. We aim to investigate the role of increased sympathetic outflow induced by emotional stress in myocardial ischemia-reperfusion (I/R) injury, and explore the underlying mechanisms. METHODS AND RESULTS: We used Designer Receptors Exclusively Activated by Designer Drugs technique to activate the ventromedial hypothalamus (VMH), a critical emotion-related nucleus. The results revealed that emotional stress stimulated by VMH activation increased sympathetic outflow, enhanced blood pressure, aggravated myocardial I/R injury, and exacerbated infarct size. The RNA-seq and molecular detection demonstrated that toll-like receptor 7 (TLR7), myeloid differentiation factor 88 (MyD88), interferon regulatory factor 5 (IRF5), and downstream inflammatory markers in cardiomyocytes were significantly upregulated. Emotional stress-induced sympathetic outflow further exacerbated the disorder of the TLR7/MyD88/IRF5 inflammatory signaling pathway. While inhibition of the signaling pathway partially alleviated myocardial I/R injury aggravated by emotional stress-induced sympathetic outflow. CONCLUSION: Increased sympathetic outflow induced by emotional stress activates TLR7/MyD88/IRF5 signaling pathway, ultimately aggravating I/R injury.


Assuntos
Traumatismo por Reperfusão Miocárdica , Angústia Psicológica , Traumatismo por Reperfusão , Humanos , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 7 Toll-Like , Receptor 4 Toll-Like/metabolismo , Transdução de Sinais , Fatores Reguladores de Interferon/metabolismo , Traumatismo por Reperfusão/metabolismo
6.
Phys Chem Chem Phys ; 25(8): 6079-6088, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752046

RESUMO

Magnetic clusters on an insulating substrate are potential candidates for spin-based quantum devices. Here we investigate the geometric, electronic, and magnetic structures of small Ti and Cr clusters, from dimers to pentamers, adsorbed on a single-layer hexagonal boron nitride (h-BN) sheet within the framework of density functional theory. The stable adsorption configurations of the Ti clusters and Cr clusters composed of the same number of atoms are found to be totally different from each other. The difference in their bonding mechanisms has been revealed by the density of states and the charge density difference of the corresponding adsorption systems. While chemical bonds are formed between the Ti atoms and the supporting sheet, the Cr clusters are found in the physisorption state on the substrate. In addition, it is shown that the h-BN sheet is energetically favorable for building three-dimensional Ti clusters. These findings support the use of h-BN as a suitable decoupling substrate for manipulation of quantum spin states in small transition metal (TM) clusters and fabrication of devices based on them.

7.
Phys Chem Chem Phys ; 25(24): 16559-16569, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37309184

RESUMO

The coexistence of spin-orbit coupling and piezoelectricity in a single material may have potential application in multifunctional devices, including spintronics, nanorobotics and piezotronics. Spin-orbit coupling provides a new means to manipulate electron's spin without an additional external magnetic field, while piezoelectricity refers to the interplay between mechanical stresses and electric polarization. Using first-principles calculations, the structural, electronic, optical, spin, and piezoelectric properties of the Janus Ge2XY (X ≠ Y = P, As, Sb, and Bi) monolayers were systematically investigated. All the Ge2XY are energetically and dynamically stable in the α phase. At the GW level, Ge2AsSb, Ge2AsBi, and Ge2SbBi have direct fundamental band gaps of 0.65, 0.64, and 0.91 eV. At the GW + BSE level, their optical gaps are 0.42, 0.45, and 0.63 eV, and the optical absorption coefficients can reach about 10-5 cm-1 in the infrared light region, which reveals that they have potential for application in infrared photodetectors. For Ge2PBi, Ge2AsBi, and Ge2SbBi containing the heavy Bi element, the lowermost conduction band and uppermost valence band have large spin splitting along the M-K and K-Γ lines, and the bands near the Fermi level possess Rashba spin splitting at the Γ point. Ge2PBi and Ge2SbBi have both large in-plane piezoelectric coefficients d11 (-0.75 and -3.18 pm V-1) and out-of-plane piezoelectric coefficients d31 (0.37 and 0.30 pm V-1). Our findings are helpful to understand the mechanism of the spin-orbit physics and piezoelectricity of Janus Ge2XY monolayers and guide experiments in exploring novel multifunctional materials.

8.
J Med Internet Res ; 25: e52464, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-38048156

RESUMO

BACKGROUND: The advantages of multimodal digitally transformed mobile health management for patients diagnosed with mild to moderate hypertension are not yet established. OBJECTIVE: We aim to evaluate the therapeutic benefits of a novel WeChat-based multimodal digital transforming management model in mobile health blood pressure (BP) management. METHODS: This randomized controlled clinical trial included 175 individuals with new-onset mild to moderate hypertension who were admitted to our center between September and October 2022. The patients were randomly assigned to either the multimodal intervention group (n=88) or the usual care group (n=87). The primary composite outcome was home and office BP differences after 6 months. The major secondary outcomes were 6-month quality-of-life scores, including the self-rating anxiety scale, self-rating depression scale, and Pittsburgh Sleep Quality Index. RESULTS: The mean home BP decreased from 151.74 (SD 8.02)/94.22 (SD 9.32) to 126.19 (SD 8.45)/82.28 (SD 9.26) mm Hg in the multimodal intervention group and from 150.78 (SD 7.87)/91.53 (SD 9.78) to 133.48 (SD 10.86)/84.45 (SD 9.19) mm Hg in the usual care group, with a mean difference in systolic blood pressure and diastolic blood pressure of -8.25 mm Hg (95% CI -11.71 to -4.78 mm Hg; P<.001) and -4.85 mm Hg (95% CI -8.41 to -1.30 mm Hg; P=.008), respectively. The mean office BP decreased from 153.64 (SD 8.39)/93.56 (SD 8.45) to 127.81 (SD 8.04)/ 82.16 (SD 8.06) mm Hg in the multimodal intervention group and from 151.48 (SD 7.14)/(91.31 (SD 9.61) to 134.92 (SD 10.11)/85.09 (SD 8.26) mm Hg in the usual care group, with a mean difference in systolic blood pressure and diastolic blood pressure of -9.27 mm Hg (95% CI -12.62 to -5.91 mm Hg; P<.001) and -5.18 mm Hg (95% CI -8.47 to -1.89 mm Hg; P=.002), respectively. From baseline to 6 months, home BP control <140/90 mm Hg was achieved in 64 (72.7%) patients in the multimodal intervention group and 46 (52.9%) patients in the usual care group (P=.007). Meanwhile, home BP control <130/80 mm Hg was achieved in 32 (36.4%) patients in the multimodal intervention group and 16 (18.4%) patients in the usual care group (P=.008). After 6 months, there were significant differences in the quality-of-life total and graded scores, including self-rating anxiety scale scores (P=.04), self-rating depression scale scores (P=.03), and Pittsburgh Sleep Quality Index scores (P<.001), in the multimodal intervention group compared with the usual care group. CONCLUSIONS: The WeChat-based multimodal intervention model improved the BP control rates and lowered the BP levels more than the usual care approach. The multimodal digital transforming management model for hypertension represents an emerging medical practice that utilizes the individual's various risk factor profiles for primary care and personalized therapy decision-making in patients with hypertension. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200063550; https://www.chictr.org.cn/showproj.html?proj=175816.


Assuntos
Saúde Digital , Hipertensão , Aplicativos Móveis , Humanos , Povo Asiático , Pressão Sanguínea , Hospitalização , Hipertensão/terapia , Qualidade de Vida
9.
Basic Res Cardiol ; 117(1): 34, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35819552

RESUMO

The stellate ganglia play an important role in cardiac remodeling after myocardial infarction (MI). This study aimed to investigate whether adiponectin (APN), an adipokine mainly secreted by adipose tissue, could modulate the left stellate ganglion (LSG) and exert cardioprotective effects through the sympathetic nervous system (SNS) in a canine model of MI. APN microinjection and APN overexpression with recombinant adeno-associated virus vector in the LSG were performed in acute and chronic MI models, respectively. The results showed that acute APN microinjection decreased LSG function and neural activity, and suppressed ischemia-induced ventricular arrhythmia. Chronic MI led to a decrease in the effective refractory period and action potential duration at 90% and deterioration in echocardiography performance, all of which was blunted by APN overexpression. Moreover, APN gene transfer resulted in favorable heart rate variability alteration, and decreased cardiac SNS activity, serum noradrenaline and neuropeptide Y, which were augmented after MI. APN overexpression also decreased the expression of nerve growth factor and growth associated protein 43 in the LSG and peri-infarct myocardium, respectively. Furthermore, RNA sequencing of LSG indicated that 4-week MI up-regulated the mRNA levels of macrophage/microglia activation marker Iba1, chemokine ligands (CXCL10, CCL20), chemokine receptor CCR5 and pro-inflammatory cytokine IL6, and downregulated IL1RN and IL10 mRNA, which were reversed by APN overexpression. Our results reveal that APN inhibits cardiac sympathetic remodeling and mitigates cardiac remodeling after MI. APN-mediated gene therapy may provide a potential therapeutic strategy for the treatment of MI.


Assuntos
Adiponectina , Infarto do Miocárdio , Adiponectina/genética , Adiponectina/metabolismo , Animais , Arritmias Cardíacas/prevenção & controle , Cães , Infarto do Miocárdio/metabolismo , RNA Mensageiro , Remodelação Ventricular
10.
J Pineal Res ; 73(4): e12829, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36031757

RESUMO

Light in the external environment might affect cardiovascular function. The light disruption seems to be related to changes in cardiovascular physiological functions, and disturbing light may be a risk factor for cardiovascular diseases. Prior studies have found that light disruption after myocardial infarction (MI) exacerbates cardiac remodeling, and the brain-heart sympathetic nervous system may be one of the key mechanisms. However, how to improve light-disrupted cardiac remodeling remains unclear. Melatonin is an indoleamine secreted by the pineal gland and controlled by endogenous circadian oscillators within the suprachiasmatic nucleus, which is closely associated with light/dark cycle. This study aimed to explore whether melatonin could improve light-disrupted cardiac remodeling and modulate the brain-heart sympathetic nervous system. Our study revealed that light disruption reduced serum melatonin levels, aggravated cardiac sympathetic remodeling, caused overactivation of the brain-heart sympathetic nervous system, exacerbated cardiac dysfunction, and increased cardiac fibrosis after MI, while melatonin treatment improved light disruption-exacerbated cardiac remodeling and brain-heart sympathetic hyperactivation after MI. Furthermore, RNA-Seq results revealed the significant changes at the cardiac transcription level. In conclusion, melatonin may be a potential therapy for light-disrupted cardiac remodeling.


Assuntos
Melatonina , Infarto do Miocárdio , Glândula Pineal , Humanos , Remodelação Ventricular , Núcleo Supraquiasmático/fisiologia
11.
J Neurosci ; 40(6): 1355-1365, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31882402

RESUMO

Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, resulted from the silencing of the Fmr1 gene and the subsequent loss of fragile X mental retardation protein (FMRP). Spine dysgenesis and cognitive impairment have been extensively characterized in FXS; however, the underlying mechanism remains poorly understood. As an important regulator of spine maturation, intercellular adhesion molecule 5 (ICAM5) mRNA may be one of the targets of FMRP and involved in cognitive impairment in FXS. Here we show that in Fmr1 KO male mice, ICAM5 was excessively expressed during the late developmental stage, and its expression was negatively correlated with the expression of FMRP and positively related with the morphological abnormalities of dendritic spines. While in vitro reduction of ICAM5 normalized dendritic spine abnormalities in Fmr1 KO neurons, and in vivo knockdown of ICAM5 in the dentate gyrus rescued the impaired spatial and fear memory and anxiety-like behaviors in Fmr1 KO mice, through both granule cell and mossy cell with a relative rate of 1.32 ± 0.15. Furthermore, biochemical analyses showed direct binding of FMRP with ICAM5 mRNA, to the coding sequence of ICAM5 mRNA. Together, our study suggests that ICAM5 is one of the targets of FMRP and is implicated in the molecular pathogenesis of FXS. ICAM5 could be a therapeutic target for treating cognitive impairment in FXS.SIGNIFICANCE STATEMENT Fragile X syndrome (FXS) is characterized by dendritic spine dysgenesis and cognitive dysfunctions, while one of the FMRP latent targets, ICAM5, is well established for contributing both spine maturation and learning performance. In this study, we examined the potential link between ICAM5 mRNA and FMRP in FXS, and further investigated the molecular details and pathological consequences of ICAM5 overexpression. Our results indicate a critical role of ICAM5 in spine maturation and cognitive impairment in FXS and suggest that ICAM5 is a potential molecular target for the development of medication against FXS.


Assuntos
Disfunção Cognitiva/metabolismo , Espinhas Dendríticas/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Regulação da Expressão Gênica/fisiologia , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Disfunção Cognitiva/genética , Espinhas Dendríticas/patologia , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/complicações , Síndrome do Cromossomo X Frágil/genética , Masculino , Camundongos , Camundongos Knockout , Neurogênese/genética
12.
J Biol Chem ; 295(4): 1120-1141, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31852739

RESUMO

The NLR family pyrin domain containing 3 (NLRP3) inflammasome is one of the best-characterized inflammasomes in humans and other mammals. However, knowledge about the NLRP3 inflammasome in nonmammalian species remains limited. Here, we report the molecular and functional identification of an NLRP3 homolog (DrNLRP3) in a zebrafish (Danio rerio) model. We found that DrNLRP3's overall structural architecture was shared with mammalian NLRP3s. It initiates a classical inflammasome assembly for zebrafish inflammatory caspase (DrCaspase-A/-B) activation and interleukin 1ß (DrIL-1ß) maturation in an apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC)-dependent manner, in which DrNLRP3 organizes DrASC into a filament that recruits DrCaspase-A/-B by homotypic pyrin domain (PYD)-PYD interactions. DrCaspase-A/-B activation in the DrNLRP3 inflammasome occurred in two steps, with DrCaspase-A being activated first and DrCaspase-B second. DrNLRP3 also directly activated full-length DrCaspase-B and elicited cell pyroptosis in a gasdermin E (GSDME)-dependent but ASC-independent manner. These two events were tightly coordinated by DrNLRP3 to ensure efficient IL-1ß secretion for the initiation of host innate immunity. By knocking down DrNLRP3 in zebrafish embryos and generating a DrASC-knockout (DrASC-/-) fish clone, we characterized the function of the DrNLRP3 inflammasome in anti-bacterial immunity in vivo The results of our study disclosed the origin of the NLRP3 inflammasome in teleost fish, providing a cross-species understanding of the evolutionary history of inflammasomes. Our findings also indicate that the NLRP3 inflammasome may coordinate inflammatory cytokine processing and secretion through a GSDME-mediated pyroptotic pathway, uncovering a previously unrecognized regulatory function of NLRP3 in both inflammation and cell pyroptosis.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Receptores de Estrogênio/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Caspases/metabolismo , Células HEK293 , Humanos , Camundongos , Agregados Proteicos , Receptores de Estrogênio/química , Proteínas de Peixe-Zebra/química
13.
Biochem Biophys Res Commun ; 517(4): 741-748, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400857

RESUMO

Spinal cord injury (SCI) is a devastating neurological condition that results in progressive tissue loss, secondary to vascular dysfunction and inflammation. Lack of effective pharmacotherapies for SCI is mainly attributable to an incomplete understanding of its pathogenesis. Stimulator of interferon gene (Sting), also known as Transmembrane protein 173 (TMEM173), activates the type I interferon-regulated innate immune response, playing crucial role in modulating inflammation. However, the mechanism underlying Sting activation in SCI is still unclear. Here, we reported that Sting functioned as a positive regulator of SCI. Sting expression was increased in the injured spinal cord samples of SCI mice, along with significantly up-regulated levels of pro-inflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-6. Suppressing Sting expression in lipopolysaccharide-incubated mouse microglia markedly reduced the activation of nuclear factor-κB (NF-κB) and mitogen activated protein kinases (MAPKs) signaling pathways, as illustrated by the decreased phosphorylation of IKKß, IκBα, NF-κB/p65, p38, ERK1/2 and JNK. Furthermore, LPS-stimulated release of pro-inflammatory cytokines in microglial cells was also reversed by Sting knockdown. In contrast, LPS-induced inflammation was further accelerated in microglial cells with Sting over-expression through potentiating NF-κB and MAPKs signaling. Mechanistically, Sting directly interacted with the TANK-binding kinase 1 (TBK1), thus promoting its phosphorylation and the activation of down-streaming NF-κB and MAPKs signaling pathways. Notably, the effects of Sting on SCI progression were verified in mice. Consistently, Sting knockout alleviated inflammatory response and facilitated recovery after SPI in mice through blocking TBK1 activation and subsequent NF-κB and MAPKs phosphorylation. In summary, our findings may provide a novel strategy for prevention and treatment of SCI by targeting Sting.


Assuntos
Inflamação/metabolismo , Inflamação/patologia , Proteínas de Membrana/metabolismo , Microglia/metabolismo , Microglia/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Animais , Linhagem Celular , Citocinas/metabolismo , Ativação Enzimática , Mediadores da Inflamação , Lipopolissacarídeos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Ligação Proteica
14.
ACS Appl Mater Interfaces ; 16(5): 6462-6473, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38266189

RESUMO

The peelable microwave absorption (MA) coating with reversible adhesion for stable presence on substrates and easy release without any residuals is highly desired in temporary electromagnetic protection, which can quickly enter and disengage the electromagnetic protection state according to the real-time changeable harsh surroundings. On the contrary, with the incorporation of abundant absorbent to achieve excellent MA ability, the tunable adhesion and sufficient cohesion are extremely challenging to fulfill the above requirement. The reported peelable coatings still have problems in controlling adhesion/cohesion strength and coating release, facing substantial residuals after peeling even using complex chemical modification or abundant additives. Herein, a peelable MA coating based on the block characteristics of polar and nonpolar segments of poly(styrene-(ethylene-co-butylene)-styrene) (SEBS) is successfully developed. The polyaniline-decorated carbon nanotube as a microwave absorber plays a positive influence on the adhesion/cohesion of the coating due to bonding interaction. The competitive effective absorption bandwidth (EAB) of 8.8 GHz and controllable yet reversible adhesion release on various substrates and complex surfaces have been achieved. The reusability endows peelable MA coating with 93% retention of EAB even after ten coating-peeling cycles. The coating with excellent chemical and adhesion stability can effectively protect substrates from salt/acid/alkali corrosion, showing over 98% retention of EAB even after 8 h of accelerated corrosion. Our peelable MA coating via a general yet reliable approach provides a prospect for temporary electromagnetic protection.

15.
Heart Rhythm ; 21(5): 610-619, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38160759

RESUMO

BACKGROUND: Neural remodeling in the left stellate ganglion (LSG), as mediated by neuroimmune reactions, promotes cardiac sympathetic nerve activity (SNA) and thus increases the incidence of ventricular arrhythmias (VAs). Interleukin-6 (IL-6) is an important factor of the neuroimmune interaction. OBJECTIVE: The present study explored the effects of IL-6 on LSG hyperactivity and the incidence of VAs. METHODS: Eighteen beagles were randomly allocated to a control group (saline with myocardial infarction [MI], n = 6), adeno-associated virus (AAV) group (AAV with MI, n = 6), and IL-6 group (overexpression of IL-6 via AAV vector with MI, n = 6). Ambulatory electrocardiography was performed before and 30 days after AAV microinjection into the LSG. LSG function and ventricular electrophysiology were assessed at 31 days after surgery, and a canine MI model was established. Samples of the LSG were collected for immunofluorescence staining and molecular biological evaluation. Blood samples and 24-hour Holter data were obtained from 24 patients with acute MI on the day after they underwent percutaneous coronary intervention to assess the correlation between IL-6 levels and SNA. RESULTS: IL-6 overexpression increased cardiac SNA and worsened postinfarction VAs. Furthermore, sustained IL-6 overexpression enhanced LSG function, promoted expression of nerve growth factor, c-fos, and fos B in the LSG, and activated the signal transducer and activator of transcription 3/regulator of G protein signalling 4 signaling pathway. Clinical sample analysis revealed a correlation between serum IL-6 levels and heart rate variability frequency domain index as well as T-wave alternans. CONCLUSION: IL-6 levels are correlated with cardiac SNA. Chronic overexpression of IL-6 mediates LSG neural remodeling through the signal transducer and activator of transcription 3/regulator of G protein signalling 4 signaling pathway, elevating the risk of VA after MI.


Assuntos
Modelos Animais de Doenças , Interleucina-6 , Gânglio Estrelado , Animais , Cães , Interleucina-6/metabolismo , Gânglio Estrelado/metabolismo , Arritmias Cardíacas/etiologia , Masculino , Eletrocardiografia Ambulatorial/métodos , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Sistema Nervoso Simpático/metabolismo , Neuroimunomodulação/fisiologia , Humanos , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/terapia
16.
iScience ; 27(3): 109163, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38425841

RESUMO

Doxorubicin (Dox) poses a considerable threat to patients owing to its cardiotoxicity, thus limiting its clinical utility. Optimal cardioprotective intervention strategies are needed to suppress tumor growth but also minimize cardiac side effects. Here, we showed that tragus vagus nerve stimulation (tVNS) improved the imbalanced autonomic tone, ameliorated impaired cardiac function and fibrosis, attenuated myocyte apoptosis, and mitochondrial dysfunction compared to those in the Dox group. The beneficial effects were attenuated by methyllycaconitine citrate (MLA). The transcript profile revealed that there were 312 differentially expressed genes and the protection of tVNS and retardation of MLA were related to inflammatory response and NADPH oxidase activity. In addition, tVNS synergizing with Dox inhibited tumor growth and lung metastasis and promoted apoptosis of tumor cells in an anti-tumor immunity manner. These results indicated that non-invasive neuromodulation can play a dual role in preventing Dox-induced cardiotoxicity and suppressing tumor growth through inflammation and oxidative stress.

17.
Hum Gene Ther ; 35(3-4): 114-122, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38131291

RESUMO

The cardiac autonomic nervous system (CANS) is intimately connected to the regulation of electrophysiology and arrhythmogenesis in cardiac systems. This work aimed at investigating whether interleukin-10 (IL-10) could effectively modulate CANS and suppress ischemia-induced ventricular arrhythmia (VA) through chronically acting on the cardiac sympathetic ganglion (CSG). Using an adeno-associated virus (AAV), we achieved local chronic overproduction of IL-10 in the CSG, left stellate ganglion (LSG). As a result, in the IL-10 group, we observed a decreased number of tyrosine hydroxylase-positive (TH+) cells in the LSG. IL-10 markedly downregulated the nerve growth factor, synaptophysin, as well as growth-associated protein 43 expression. In vivo, results from ambulatory electrocardiography showed that IL-10 overexpression significantly inhibited the cardiac sympathetic nervous system activity and improved heart rate variability. Meanwhile, we observed decreased LSG function as well as prolonged ventricular effective refractory period and suppressed VA after myocardial infarction (MI) in the IL-10 group. In addition, IL-10 overexpression attenuated inflammation and decreased norepinephrine levels in the myocardium after acute MI. In conclusion, our data suggest that chronic IL-10 overexpression modulates cardiac sympathetic nerve remodeling and suppresses VA induced by MI. Neuromodulation through AAV-mediated IL-10 overexpression may have the characteristics of and advantages as a potential neuroimmunotherapy for preventing MI-induced VAs.


Assuntos
Interleucina-10 , Infarto do Miocárdio , Animais , Interleucina-10/genética , Interleucina-10/metabolismo , Coração , Arritmias Cardíacas/genética , Arritmias Cardíacas/terapia , Arritmias Cardíacas/metabolismo , Infarto do Miocárdio/metabolismo , Gânglio Estrelado/metabolismo , Transgenes , Modelos Animais de Doenças
18.
Materials (Basel) ; 16(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37241489

RESUMO

TiMoNbX (X = Cr, Ta, Zr) RHEA coatings were fabricated on TC4 titanium alloy substrate using laser cladding technology. The microstructure and corrosion resistance of the RHEA were studied by XRD, SEM and an electrochemical workstation. The results show that the TiMoNb series RHEA coating was composed of a columnar dendrite (BCC) phase, a rod-like second phase, a needle-like structure and equiaxed dendrite, but the TiMoNbZr RHEA coating showed high-density defects, similar to those in TC4 titanium alloy, which were composed of small non-equiaxed dendrites and lamellar α'(Ti). In the 3.5% NaCl solution, compared with TC4 titanium alloy, the RHEA had a lower corrosion sensitivity and fewer corrosion sites, showing better corrosion resistance. The corrosion resistance of the RHEA ranged from strong to weak in this order: TiMoNbCr, TiMoNbZr, TiMoNbTa and TC4. The reason is that the electronegativity of different elements is different, and the speeds of the formation of the passivation film were very different. In addition, the positions of pores appearing in the laser cladding process also affected the corrosion resistance.

19.
ACS Appl Mater Interfaces ; 15(21): 25990-25999, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37204088

RESUMO

Polyimide (PI) foam with excellent microwave absorption (MA) performance and desirable compressive strength is highly critical and in demand in the structural MA components. Although the satisfactory MA performance of the present PI-based MA foams has been achieved by employing diverse methods, the relatively low compressive strength (∼KPa) restricted them from use as structural MA foams in practical application. Herein, isocyanate acid was introduced to the backbone of PI resin, which not only increased the PI backbone polarity and strength as rigid chain segment, but also served as a self-foaming component. The porous structure of PI foams was readily regulated by adjusting the water and carbon nanotube (CNT) filler contents of precursor dispersion. As a result of the improved polarity of the PI backbone resulted from the isocyanate group and high dielectric loss of CNT, the high compressive strength of 7.04 MPa and impressive MA property of the resultant PI foam with a low CNT loading ratio of 1.5 wt % were achieved, which were much higher than those reported previously. Especially, the effective absorption bandwidth (EAB) (RL < -10 dB) was up to 10.7 GHz (at the thickness of 3 mm), covering the C, X, and Ku bands simultaneously. Meanwhile, the EAB of the as-prepared PI foam retained 9.3 and 9.7 GHz even after being subjected to liquid nitrogen (-196 °C) and high temperature (300 °C) treatments due to the desirable stability of PI. In addition, the excellent thermal insulation resulted from the pores structure and low filler content was achieved, where the top surface only presented 60 °C after placing on 300 °C platform for 30 min. The high compressive strength, impressive MA property, and thermal insulation endowed the resultant CNT/PI foam with great potential application as structural MA foam in a harsh service environment.

20.
J Colloid Interface Sci ; 649: 501-509, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37356151

RESUMO

The impedance matching performance of carbon nanotubes (CNTs) can be effectively enhanced by developing a uniform magnetic impedance matching layer, which can take on critical significance in achieving the desirable microwave absorption (MA) performance. To obtain a uniform coating of Nickel (Ni) nanoparticles on CNTs, several methods have been developed (e.g., the γ-irradiation technique, electroless deposition, as well as microwave welding method). However, the intricate and complicated conditions of the above-mentioned methods limit their wide application. Therefore, controlling the distribution of Ni nanoparticles with the aid of a concise and effective method remains a great challenge. Herein, in view of the uniform dispersion effect of polyvinylpyrrolidone (PVP) on CNTs and its complexation with Ni ions, uniform coating of Ni nanoparticles on CNTs is well developed after it is introduced in the hydrothermal process. The prepared Ni/CNTs composites exhibited excellent MA performance in comparison with those of reported Ni/CNTs composites for the ideal impedance matching performance and microwave attenuation ability. When the filler content was only 15 wt%, the minimum reflection loss (RLmin) reached -39.5 dB, and the effective bandwidth (EB) with RL < -10 dB reached 5.2 GHz at the thickness of 1.15 mm. A scalable strategy of regulating the distribution of Ni nanoparticles and preparing a lightweight microwave absorber based on CNTs was developed in this study, which can serve as a vital guideline for preparing novel MA composite materials.

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