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1.
J Colloid Interface Sci ; 669: 23-31, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38703579

RESUMEN

Although ordered porous carbon materials (PCMs) have shown promising potential in the field of electromagnetic wave absorption (EWA), creating multifunctional PCMs with outstanding microwave absorption performance remains a significant challenge. Herein, ordered porous carbon aerogels loaded with pea-pod-like nitrogen-doped carbon nanotubes (CNTs) were fabricated via orientation freeze-drying followed by high-temperature pyrolysis. The optimized aerogel exhibits extraordinary EWA performance with a broad effective absorption bandwidth of 7.68 GHz and exceptionally strong absorption of -91.58 dB at a low filling ratio of only 3 wt%, which is the largest absorption strength among all known aerogels to date. The exceptional EWA performance is attributed to the synergistic effect of abundant loss mechanisms resulting from a unique pod-like structure in ordered porous carbon aerogel, where nitrogen-doped CNTs encapsulate magnetic alloy nanoparticles. Optimized aerogel exhibits superior compressive elasticity, thermal insulation, and light weight, laying the groundwork for designing practical next-generation EWA materials.

2.
Neurogenetics ; 25(2): 131-139, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38460076

RESUMEN

Twin and family studies have established the genetic contribution to idiopathic generalized epilepsy (IGE). The genetic architecture of IGE is generally complex and heterogeneous, and the majority of the genetic burden in IGE remains unsolved. We hypothesize that gene-gene interactions contribute to the complex inheritance of IGE. CNTN2 (OMIM* 615,400) variants have been identified in cases with familial adult myoclonic epilepsy and other epilepsies. To explore the gene-gene interaction network in IGE, we took the CNTN2 gene as an example and investigated its co-occurrent genetic variants in IGE cases. We performed whole-exome sequencing in 114 unrelated IGE cases and 296 healthy controls. Variants were qualified with sequencing quality, minor allele frequency, in silico prediction, genetic phenotype, and recurrent case numbers. The STRING_TOP25 gene interaction network analysis was introduced with the bait gene CNTN2 (denoted as A). The gene-gene interaction pair mode was presumed to be A + c, A + d, A + e, with a leading gene A, or A + B + f, A + B + g, A + B + h, with a double-gene A + B, or other combinations. We compared the number of gene interaction pairs between the case and control groups. We identified three pairs in the case group, CNTN2 + PTPN18, CNTN2 + CNTN1 + ANK2 + ANK3 + SNTG2, and CNTN2 + PTPRZ1, while we did not discover any pairs in the control group. The number of gene interaction pairs in the case group was much more than in the control group (p = 0.021). Taking together the genetic bioinformatics, reported epilepsy cases, and statistical evidence in the study, we supposed CNTN2 as a candidate pathogenic gene for IGE. The gene interaction network analysis might help screen candidate genes for IGE or other complex genetic disorders.


Asunto(s)
Contactinas , Epilepsia Generalizada , Epistasis Genética , Redes Reguladoras de Genes , Predisposición Genética a la Enfermedad , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven , Estudios de Casos y Controles , Contactinas/genética , Epilepsia Generalizada/genética , Secuenciación del Exoma , Frecuencia de los Genes
3.
Neurogenetics ; 24(3): 161-169, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37022522

RESUMEN

Gene sub-region encoded protein domain is the basic unit for protein structure and function. The DMD gene is the largest coding gene in humans, with its phenotype relevant to idiopathic generalized epilepsy. We hypothesized variants clustered in sub-regions of idiopathic generalized epilepsy genes and investigated the relationship between the DMD gene and idiopathic generalized epilepsy. Whole exome sequencing was performed in 106 idiopathic generalized epilepsy individuals. DMD variants were filtered with variant type, allele frequency, in silico prediction, hemizygous or homozygous status in the population, inheritance mode, and domain location. Variants located at the sub-regions were selected by the subRVIS software. The pathogenicity of variants was evaluated by the American College of Medical Genetics and Genomics criteria. Articles on functional studies related to epilepsy for variants clustered protein domains were reviewed. In sub-regions of the DMD gene, two variants were identified in two unrelated cases with juvenile absence epilepsy or juvenile myoclonic epilepsy. The pathogenicity of both variants was uncertain significance. Allele frequency of both variants in probands with idiopathic generalized epilepsy reached statistical significance compared with the population (Fisher's test, p = 2.02 × 10-6, adjusted α = 4.52 × 10-6). The variants clustered in the spectrin domain of dystrophin, which binds to glycoprotein complexes and indirectly affects ion channels contributing to epileptogenesis. Gene sub-region analysis suggests a weak association between the DMD gene and idiopathic generalized epilepsy. Functional analysis of gene sub-region helps infer the pathogenesis of idiopathic generalized epilepsy.


Asunto(s)
Epilepsia Generalizada , Epilepsia , Humanos , Epilepsia Generalizada/genética , Frecuencia de los Genes , Fenotipo
4.
Front Neurorobot ; 16: 922756, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225260

RESUMEN

In the study of articulatory phonetics, lip shape and tongue position is the focus of linguists. In order to reveal the physiological characteristics of the lip shape during pronunciation, the author takes the Tibetan Xiahe dialect as the research object and defines the facial parameter feature points of the speaker according to the MPEG-4 international standard. Most importantly, the author uses the facial motion capture technology to obtain the dynamic lip viseme feature data, during the stop's forming-block, continuing-block, removing-block, and co-articulation with vowels in the CV structure. Through research and analysis, it is found that the distribution of lip shape change the characteristics of different parts' pronunciation is different during the stop's forming block. In the co-articulation with [a], the reverse effect is greater than the forward effect, which is consistent with the relevant conclusions in many languages obtained by many scholars through other experimental methods. The study also found that in the process of pronunciation, the movement of the lip physiological characteristics of each speaker is random to a certain extent, but when different speakers pronounce the same sound, they can always maintain the consistency of the changing trend of the lip shape characteristics.

5.
Brain Behav ; 12(7): e2634, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35608154

RESUMEN

BACKGROUND: Trigeminal neuralgia (TN) is a neuropathic pain that occurs in branches of the trigeminal nerve. MicroRNAs (miRNAs) have been considered key mediators of neuropathic pain. This study was aimed to elucidate the pathophysiological function and mechanisms of miR-223-3p in mouse models of TN. METHODS: Infraorbital nerve chronic constriction injury (CCI-ION) was applied in male C57BL/6J mice to establish mouse models of TN. Pain responses were assessed utilizing Von Frey method. The expression of miR-223-3p, MKNK2, and MAPK/ERK pathway protein in trigeminal ganglions (TGs) of CCI-ION mice was measured using RT-qPCR and Western blotting. The concentrations of inflammatory cytokines were evaluated using Western blotting. The relationship between miR-223-3p and MKNK2 was tested by a luciferase reporter assay. RESULTS: We found that miR-223-3p was downregulated, while MKNK2 was upregulated in TGs of CCI-ION mice. MiR-223-3p overexpression by an intracerebroventricular injection of Lv-miR-223-3p attenuated trigeminal neuropathic pain in CCI-ION mice, as well as reduced the protein levels of pro-inflammatory cytokines in TGs of CCI-ION mice. MKNK2 was verified to be targeted by miR-223-3p. Additionally, miR-223-3p overexpression decreased the phosphorylation levels of ERK1/2, JNK, and p38 protein in TGs of CCI-ION mice to inhibit MAPK/ERK signaling. CONCLUSIONS: Overall, miR-223-3p attenuates the development of TN by targeting MKNK2 to suppress MAPK/ERK signaling.


Asunto(s)
MicroARNs , Neuralgia , Neuralgia del Trigémino , Animales , Citocinas , Modelos Animales de Enfermedad , Sistema de Señalización de MAP Quinasas , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Proteínas Serina-Treonina Quinasas , Neuralgia del Trigémino/genética
6.
Neurochem Res ; 36(1): 67-75, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20848190

RESUMEN

Oxidative stress is one of the most important pathological mechanisms in neurodegenerative diseases and ischemia. Recent studies have indicated that the sonic hedgehog (SHH) signaling pathway is involved in these diseases, but the underlying mechanisms remains elusive. Here we report that the SHH pathway was activated in primary cultured cortical neurons after exposure to hydrogen peroxide (H2O2). H2O2 treatment decreased the cell viability of neurons, and inhibition of endogenous SHH signaling exacerbated its neurotoxicity. Activation of SHH signaling protected neurons from H2O2-induced apoptosis and increased the cell viability while those effects were partially reversed by blocking SHH signals. Exogenous SHH increased the activities of Superoxide dismutase (SOD) and Glutathione peroxidase (GSH-PX) in H2O2-treated neurons and decreased production of Malondialdehyde (MDA). It also promoted expression of the anti-apoptotic gene Bcl-2 and inhibited expression of pro-apoptotic gene Bax. Activation of SHH signals upregulated both Neurotrophic factors vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF). Pretreatment with SHH inhibited the activation of ERK (extracellular signal-regulated kinases) signals induced by H2O2. Our findings demonstrate that activation of SHH signaling protects cortical neurons against oxidative stress and suggest a potential role of SHH for the clinic treatments of brain ischemia and neurodegenerative disorders.


Asunto(s)
Corteza Cerebral/citología , Proteínas Hedgehog/metabolismo , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Animales , Apoptosis/fisiología , Corteza Cerebral/fisiología , Glutatión Peroxidasa/metabolismo , Proteínas Hedgehog/genética , Peróxido de Hidrógeno/farmacología , Malondialdehído/metabolismo , Neuronas/citología , Neuronas/efectos de los fármacos , Oxidantes/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología , Superóxido Dismutasa/metabolismo , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
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