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1.
Cereb Cortex ; 34(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39110410

RESUMO

Selection history refers to the notion that previous allocations of attention or suppression have the potential to elicit lingering and enduring selection biases that are isolated from goal-driven or stimulus-driven attention. However, in the singleton detection mode task, manipulating the selection history of distractors cannot give rise to pure proactive inhibition. Therefore, we employed a combination of a working memory task and a feature search mode task, simultaneously recording cortical activity using EEG, to investigate the mechanisms of suppression guided by selection history. The results from event-related potential and reaction times showed an enhanced inhibitory performance when the distractor was presented at the high-probability location, along with instances where the target appeared at the high-probability location of distractors. These findings demonstrate that a generalized proactive inhibition bias is learned and processed independent of cognitive resources, which is supported by selection history. In contrast, reactive rejection toward the low-probability location was evident through the Pd component under varying cognitive resource conditions. Taken together, our findings indicated that participants learned proactive inhibition when the distractor was at the high-probability location, whereas reactive rejection was involved at low-probability location.


Assuntos
Atenção , Eletroencefalografia , Potenciais Evocados , Memória de Curto Prazo , Tempo de Reação , Humanos , Masculino , Feminino , Adulto Jovem , Atenção/fisiologia , Tempo de Reação/fisiologia , Adulto , Potenciais Evocados/fisiologia , Memória de Curto Prazo/fisiologia , Percepção Espacial/fisiologia , Inibição Psicológica , Inibição Proativa , Aprendizagem/fisiologia , Estimulação Luminosa/métodos , Encéfalo/fisiologia
2.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338716

RESUMO

Transcription factors within microglia contribute to the inflammatory response following intracerebral hemorrhage (ICH). Therefore, we employed bioinformatics screening to identify the potential transcription factor tonicity-responsive enhancer-binding protein (TonEBP) within microglia. Inflammatory stimuli can provoke an elevated expression of TonEBP in microglia. Nevertheless, the expression and function of microglial TonEBP in ICH-induced neuroinflammation remain ambiguous. In our recent research, we discovered that ICH instigated an increased TonEBP in microglia in both human and mouse peri-hematoma brain tissues. Furthermore, our results indicated that TonEBP knockdown mitigates lipopolysaccharide (LPS)-induced inflammation and the activation of NF-κB signaling in microglia. In order to more deeply comprehend the underlying molecular mechanisms of how TonEBP modulates the inflammatory response, we sequenced the transcriptomes of TonEBP-deficient cells and sought potential downstream target genes of TonEBP, such as Pellino-1 (PELI1). PELI has been previously reported to mediate nuclear factor-κB (NF-κB) signaling. Through the utilization of CUT & RUN, a dual-luciferase reporter, and qPCR, we confirmed that TonEBP is the transcription factor of Peli1, binding to the Peli1 promoter. In summary, TonEBP may enhance the LPS-induced inflammation and activation of NF-κB signaling via PELI1.


Assuntos
Hemorragia Cerebral , Microglia , Fatores de Transcrição NFATC , Animais , Humanos , Camundongos , Hemorragia Cerebral/genética , Hemorragia Cerebral/metabolismo , Inflamação/genética , Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/metabolismo , Microglia/metabolismo , Doenças Neuroinflamatórias , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
3.
Int J Mol Sci ; 24(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37176030

RESUMO

Intracerebral hemorrhage (ICH) is a severe cerebrovascular disease with a high disability rate and high mortality, and pyroptosis is a type of programmed cell death in the acute phase of ICH. Neuronal Per-Arnt-Sim domain protein 4 (Npas4) is a specific transcription factor highly expressed in the nervous system, yet the role of NPAS4 in ICH-induced pyroptosis is not fully understood. NLR family Pyrin-domain-containing 6 (NLRP6), a new member of the Nod-like receptor family, aggravates pyroptosis via activating cysteine protease-1 (Caspase-1) and Caspase-11. In this study, we found that NPAS4 was upregulated in human and mouse peri-hematoma brain tissues and peaked at approximately 24 h after ICH modeling. Additionally, NPAS4 knockdown improved neurologic dysfunction and brain damage induced by ICH in mice after 24 h. Meanwhile, inhibiting NPAS4 expression reduced the levels of myeloperoxidase (MPO)-positive cells and Caspase-1/TUNEL-double-positive cells and decreased cleaved Caspase-1, cleaved Caspase-11, and N-terminal GSDMD levels. Consistently, NPAS4 overexpression reversed the above alternations after ICH in the mice. Moreover, NPAS4 could interact with the Nlrp6 promoter region (-400--391 bp and -33--24 bp) and activate the transcription of Nlrp6. Altogether, our study demonstrated that NPAS4, as a transcription factor, can exacerbate pyroptosis and transcriptionally activate NLRP6 in the acute phase of intracerebral hemorrhage in mice.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Camundongos , Humanos , Animais , Piroptose/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hemorragia Cerebral/genética , Hemorragia Cerebral/metabolismo , Caspase 1/genética , Caspase 1/metabolismo , Fatores de Transcrição , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
4.
Langmuir ; 36(16): 4503-4510, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32241112

RESUMO

Expansin has nonhydrolytic disruptive activity and synergistically acts with cellulases to enhance the hydrolysis of cellulose. The adsorption-desorption of expansin on noncellulosic lignin can greatly affect the action of expansin on lignocellulose. In this study, three lignins with different sources (kraft lignin (KL), sodium lignin sulfonate (SLS), and enzymatic hydrolysis lignin (EHL)) were selected as the substrates. The real-time adsorption-desorption of Bacillus subtilis expansin (BsEXLX1) on lignins was monitored using quartz crystal microgravimetry with dissipation (QCM-D). The effects of temperature and Tween 80 on the adsorption-desorption behaviors were also investigated. The results show that BsEXLX1 exhibited high binding ability on lignin and achieved maximum adsorption of 283.2, 273.8, and 266.9 ng cm-2 at 25 °C on KL, SLS, and EHL, respectively. The maximum adsorption decreased to 148.2-192.8 ng cm-2 when the temperature increased from 25 to 45 °C. Moreover, Tween 80 competitively bound to lignin and significantly prevented expansin adsorption. After irreversible adsorption of Tween 80, the maximum adsorption of BsEXLX1 greatly decreased to 33.3, 37.2, and 10.3 ng cm-2 at 25 °C on KL, SLS, and EHL, respectively. Finally, a kinetic model was developed to analyze the adsorption-desorption process of BsEXLX1. BsEXLX1 has a higher adsorption rate constant (kA) and a lower desorption rate constant (kD) on KL than on SLS and EHL. The findings of this study provide useful insights into the adsorption-desorption of expansin on lignin.

5.
Langmuir ; 34(45): 13514-13522, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30372079

RESUMO

Effective regulation of cellulase adsorption is key to improving the efficiencies of the two major bottlenecks of lignocellulose hydrolysis and cellulase recovery. In this work, we investigated the effect of inhibitors, pH, and temperature on the adsorption of exo- and endoglucanases (Cel7A and Cel7B, respectively) on cellulose using quartz crystal microgravimetry with dissipation. The addition of glucose and cellobiose can both inhibit the hydrolysis activity of Cel7A, whereas only cellobiose can inhibit that of Cel7B. Notably, the adsorption was favored by acidic conditions (pH ≤ 4.8) and low temperature, whereas alkaline conditions (pH 9 and 10) facilitated enzyme desorption, which is useful to guide the process of cellulase recovery. The adsorption and hydrolysis activity of Cel7A and Cel7B were both higher at 45 °C than at 25 °C. These findings pave the way to effective regulation of cellulase adsorption and thus improve lignocellulose conversion and cellulase recovery.


Assuntos
Celulases/química , Celulose/química , Adsorção , Celobiose/química , Celulases/antagonistas & inibidores , Inibidores Enzimáticos/química , Glucose/química , Concentração de Íons de Hidrogênio , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Temperatura , Trichoderma/enzimologia
6.
Polymers (Basel) ; 16(14)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39065393

RESUMO

The preparation of novel structures of light-diffusing particles is currently a research focus in the field of light-diffusing materials. This study, conducted by the common melt-blending process, controlled thermodynamic and kinetic factors to distribute smaller-sized organic silica bead (OSB) particles at the interface between a polycarbonate (PC) matrix and spherical island-phase styrene-acrylonitrile copolymer (SAN) for the in situ formation of compound eye-like microspheres with SAN as "large eyes" and OSBs as "small eyes". Through the multiple-scattering effects of these compound eye-like microspheres, these light-diffusing materials significantly improved the haze, scattering range, and light-shielding capabilities while maintaining high transmittance. Specifically, the PC/SAN-OSB light-scattering materials achieved a haze of 100% with an OSB content of only 0.17%, maintaining a transmittance of 88%. Compared with the PC/OSB system with the same level of haze, the addition of OSB was reduced by 88%. Therefore, this study achieved exceptionally effective light-diffusing materials through a simple, environmentally friendly, and low-cost preparation method, suitable for the scalable production of light-diffusing materials in new display and lighting fields.

7.
Nat Commun ; 15(1): 5628, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965215

RESUMO

The control of a molecule's geometry, chirality, and physical properties has long been a challenging pursuit. Our study introduces a dependable method for assembling D3-symmetric trigonal bipyramidal coordination cages. Specifically, D2h-symmetric anions, like oxalate and chloranilic anions, self-organize around a metal ion to form chiral-at-metal anionic complexes, which template the formation of D3-symmetric trigonal bipyramidal coordination cages. The chirality of the trigonal bipyramid is determined by the point chirality of chiral amines used in forming the ligands. Additionally, these cages exhibit chiral selectivity for the included chiral-at-metal anionic template. Our method is broadly applicable to various ligand systems, enabling the construction of larger cages when larger D2h-symmetric anions, like chloranilic anions, are employed. Furthermore, we successfully produce enantiopure trigonal bipyramidal cages with anthracene-containing backbones using this approach, which would be otherwise infeasible. These cages exhibit circularly polarized luminescence, which is modulable through the reversible photo-oxygenation of the anthracenes.

8.
Sci Rep ; 14(1): 20158, 2024 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215129

RESUMO

The development of intracerebral hemorrhage (ICH) is a dynamic process and intervention during the acute phase of ICH is critical for subsequent recovery. Therefore, it is crucial to screen potential signature genes and therapeutic target genes in the acute phase of ICH. In this study, based on the results of mRNA sequencing in mouse ICH and mRNA sequencing of human ICH from online databases, top five potential signature genes after ICH, Tyrobp, Itgb2, Tlr2, Ptprc and Itgam, were screened. Quantitative PCR results showed higher mRNA expression of Tyrobp, Itgb2, Tlr2, Ptprc, and Itgam in the 1-, 3- and 5-day mouse ICH groups compared to the sham-operated group. Immune infiltration correlation analysis shows that the top-ranked signature gene, Tyrobp, is negatively correlated with M2 macrophages and plasma cells, and Western blot analysis shows higher expression of the Tyrobp protein in the 1-, 3-, and 5-day mouse ICH groups compared to the sham-operated group. Furthermore, immunohistochemistry revealed that TYROBP protein expression was significantly higher in human ICH tissues than in normal brain tissues. Our results suggest that Tyrobp is a signature gene in the acute phase of ICH and may be a potential target for the treatment of the acute phase of ICH.


Assuntos
Hemorragia Cerebral , Hemorragia Cerebral/genética , Animais , Humanos , Camundongos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Perfilação da Expressão Gênica , Encéfalo/metabolismo , Encéfalo/patologia , Transcriptoma , Proteínas Adaptadoras de Transdução de Sinal
9.
Transl Pediatr ; 12(4): 681-694, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37181029

RESUMO

Background: Epilepsy is a chronic disease that is characterized by transient brain dysfunction caused by an abrupt abnormal neuronal discharge. Recent studies have indicated that the pathways related to inflammation and innate immunity play significant roles in the pathogenesis of epilepsy, suggesting an interrelationship between immunity and inflammatory processes and epilepsy. However, the immune-related mechanisms are still not precisely understood; therefore, this study aimed to explore the immune-related mechanisms in epilepsy disorders, highlight the role of immune cells at the molecular level in epilepsy, and provide therapeutic targets for patients with epilepsy. Methods: Brain tissue samples from healthy and epileptic individuals were collected for transcriptome sequencing to identify differentially expressed genes (DEGs) and differentially expressed (DE)-long coding RNAs (lncRNAs). Based on interactions from the miRcode, starBase2.0, miRDB, miRTarBase, TargetScan, and ENCORI databases, a lncRNA-associated competitive endogenous RNA (ceRNA) network was created. Gene ontology and the Kyoto encyclopedia of genes analyses established that the genes in the ceRNA network were mainly enriched in immune-related pathways. Immune cell infiltration, screening, and protein-protein interaction analyses of the immune-related ceRNAs, and correlation analysis between immune-related core messenger RNA (mRNA) and immune cells were also performed. Results: Nine hub genes (EGFR, GRB2, KRAS, FOS, ESR1, MAPK1, MAPK14, MAPK8, and PPARG) were obtained. Also, 38 lncRNAs, one miRNA (hsa-miR-27a-3p), and one mRNA (EGFR) comprised the final core ceRNA network. Mast cells, plasmacytoid dendritic cells, and immature dendritic cells all showed positive correlations with EGFR, while Cluster of differentiation 56 dim natural killer cells (CD56dim natural killer cells) showed negative correlations. Finally, we employed an epilepsy mouse model to validate EGFR, which is consistent with disease progression. Conclusions: In conclusion, the pathophysiology of epilepsy was correlated with EGFR. Thus, EGFR could be a novel biomarker of juvenile focal epilepsies, and our findings provide promising therapeutic targets for epilepsy.

10.
PhytoKeys ; 225: 153-164, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213819

RESUMO

Carexsect.Mitratae s.l. was established by Kükenthal in 1909 and can be distinguished from the closely related sections in having nutlets frequently discoid-annulate at the apex and a persistent style base. Based on field surveys and specimen examination, three new species of sect. Mitratae are described and illustrated here. Carexfatsuaniana was collected from Yunnan and differs from C.truncatigluma in having the utricles nearly glabrous, the nutlets with a ca. 0.5 mm long beak at the apex, the staminate spikes cylindrical, 5-7.5 cm long, 4-5 mm wide, and the pistillate glumes acuminate at the apex. Carexdamingshanica was collected from Guangxi and differs from C.breviscapa and C.rhynchachaenium in having 3 or 4 spikes, the lateral spikes cylindrical, the pistillate glumes, utricles and nutlets all shorter than in the other two species. Carexradicalispicula was collected from Sichuan and differs from C.truncatirostris in having the staminate spikes clavate, 1.5-2 mm wide, the pistillate glumes pale yellow-white, 3-3.2 mm long, acuminate or short-awned at the apex, and the nutlets with 3 angles shallowly constricted at the middle.

11.
J Colloid Interface Sci ; 645: 107-114, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37146374

RESUMO

Low-cost non-noble metal nanoparticles are promising electrocatalysts that can catalyze oxygen evolution reaction (OER). Various factors such as poor activity and stability hinder the practical applications of these materials. The electroactivity and durability of the electrocatalysts can be improved by optimizing the morphology and composition of the materials. Herein, we report the successful synthesis of hollow porous carbon (HPC) catalysts loaded with ternary alloy (FeCoNi) nanoparticles (HPC-FeCoNi) for efficient OER. HPC is firstly synthesized by a facile carbon deposition method using the hierarchical porous zeolite ZSM-5 as the hard template. Numerous defects are generated on the carbon shell during the removal of zeolite template. Subsequently, FeCoNi alloy nanoparticles are supported on HPC by a sequence of impregnation and H2 reduction processes. The synergistic effect between carbon defects and FeCoNi alloy nanoparticles endows the catalyst with an excellent OER performance (low overpotential of 219 mV; Tafel slope of 60.1 mV dec-1) in a solution of KOH (1 M). A stable potential is maintained during the continuous operation over 72 h. The designed HPC-FeCoNi presents a platform for the development of electrocatalysts that can be potentially applied for industrial OER.

12.
Carbohydr Polym ; 253: 117287, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278952

RESUMO

Effective binding between cellulases and cellulose is essential for enzymatic hydrolysis of lignocellulose. Expansin can loosen the cellulose structure and can enhance the efficiency of cellulase. However, possible synergy between cellulases and expansin is not clear. In this work, the real-time adsorption of exoglucanases (Cel7A) or endoglucanases (Cel7B) with Bacillus subtilis expansin (BsEXLX1) and the enzymatic hydrolysis of cellulose were followed using quartz crystal microbalance with dissipation (QCM-D). Initial adsorption rate, adsorption capacity, and pseudo-steady-state rate of cellulose hydrolysis by Cel7A/Cel7B increased in the presence of BsEXLX1. When injecting Cel7A or Cel7B together with BsEXLX1 at a mass ratio of 1:1, the hydrolysis rate was almost 5 times the rate for Cel7A or Cel7B alone at 25 °C. These results increase our understanding of the real-time synergism between cellulases and expansin on cellulose, as well as the impact of their synergy on the enzymatic hydrolysis of cellulose.


Assuntos
Celulase/química , Celulose/química , Lignina/química , Trichoderma/enzimologia , Adsorção , Bacillus subtilis/química , Proteínas de Bactérias/química , Proteínas de Bactérias/farmacologia , Celulase/isolamento & purificação , Celulase/farmacologia , Sinergismo Farmacológico , Hidrólise/efeitos dos fármacos , Cinética , Técnicas de Microbalança de Cristal de Quartzo/métodos , Temperatura
13.
Biotechnol Biofuels ; 11: 317, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479662

RESUMO

BACKGROUND: Biological pretreatment is an environmentally safe method for disrupting recalcitrant structures of lignocellulose and thereby improving their hydrolysis efficiency. Expansin and expansin-like proteins act synergistically with cellulases during hydrolysis. A systematic analysis of the adsorption behavior and mechanism of action of expansin family proteins can provide a basis for the development of highly efficient pretreatment methods for cellulosic substrates using expansins. RESULTS: Adsorption of Bacillus subtilis expansin (BsEXLX1) onto cellulose film under different conditions was monitored in real time using a quartz crystal microbalance with dissipation. A model was established to describe the adsorption of BsEXLX1 onto the film. High temperatures increased the initial adsorption rate while reducing the maximum amount of BsEXLX1 adsorbed onto the cellulose. Non-ionic surfactants (polyethylene glycol 4000 and Tween 80) at low concentrations enhanced BsEXLX1 adsorption; whereas, high concentrations had the opposite effect. However, sodium dodecyl sulfate inhibited adsorption at both low and high concentrations. We also investigated the structural changes of cellulose upon BsEXLX1 adsorption and found that BsEXLX1 adsorption decreased the crystallinity index, disrupted hydrogen bonding, and increased the surface area of cellulose, indicating greater accessibility of the substrate to the protein. CONCLUSIONS: These results increase our understanding of the interaction between expansin and cellulose, and provide evidence for expansin treatment as a promising strategy to enhance enzymatic hydrolysis of lignocellulose.

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