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1.
J Environ Sci (China) ; 149: 512-523, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181663

RESUMO

Oxygen activation leading to the generation of reactive oxygen species (ROS) is essential for photocatalytic environmental remediation. The limited efficiency of O2 adsorption and reductive activation significantly limits the production of ROS when employing C3N4 for the degradation of emerging pollutants. Doping with metal single atoms may lead to unsatisfactory efficiency, due to the recombination of photogenerated electron-hole pairs. Here, Mn and S single atoms were introduced into C3N4, resulting in the excellent photocatalytic performances. Mn/S-C3N4 achieved 100% removal of bisphenol A, with a rate constant 11 times that of pristine C3N4. According to the experimental results and theoretical simulations, S-atoms restrict holes, facilitating the photo-generated carriers' separation. Single-atom Mn acts as the O2 adsorption site, enhancing the adsorption and activation of O2, resulting the generation of ROS. This study presents a novel approach for developing highly effective photocatalysts that follows a new mechanism to eliminate organic pollutants from water.


Assuntos
Oxigênio , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Oxigênio/química , Catálise , Manganês/química , Compostos Benzidrílicos/química , Nitrilas/química , Adsorção , Espécies Reativas de Oxigênio , Recuperação e Remediação Ambiental/métodos , Fenóis/química
2.
Elife ; 132024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963410

RESUMO

The sensorimotor system can recalibrate itself without our conscious awareness, a type of procedural learning whose computational mechanism remains undefined. Recent findings on implicit motor adaptation, such as over-learning from small perturbations and fast saturation for increasing perturbation size, challenge existing theories based on sensory errors. We argue that perceptual error, arising from the optimal combination of movement-related cues, is the primary driver of implicit adaptation. Central to our theory is the increasing sensory uncertainty of visual cues with increasing perturbations, which was validated through perceptual psychophysics (Experiment 1). Our theory predicts the learning dynamics of implicit adaptation across a spectrum of perturbation sizes on a trial-by-trial basis (Experiment 2). It explains proprioception changes and their relation to visual perturbation (Experiment 3). By modulating visual uncertainty in perturbation, we induced unique adaptation responses in line with our model predictions (Experiment 4). Overall, our perceptual error framework outperforms existing models based on sensory errors, suggesting that perceptual error in locating one's effector, supported by Bayesian cue integration, underpins the sensorimotor system's implicit adaptation.


Assuntos
Adaptação Fisiológica , Teorema de Bayes , Sinais (Psicologia) , Humanos , Masculino , Adulto , Adulto Jovem , Feminino , Desempenho Psicomotor/fisiologia , Aprendizagem/fisiologia , Percepção Visual/fisiologia , Propriocepção/fisiologia
3.
PLoS One ; 19(5): e0303740, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748639

RESUMO

Acute kidney injury (AKI) is a sudden loss of renal function with a high mortality rate and inflammation is thought to be the underlying cause. The phenylpropanoid components acteoside (ACT) and isoacteoside (ISO), which were isolated from Cistanche deserticola Y.C.Ma, have been reported to have preventive effects against kidney disorders. This study aimed to investigate the anti-inflammatory properties and protective mechanisms of ACT and ISO. In this investigation, kidney function was assessed using a semi-automatic biochemical analyzer, histopathology was examined using Hematoxylin-Eosin staining and immunohistochemistry, and the concentration of inflammatory cytokines was assessed using an enzyme-linked immunosorbent assay (ELISA) test. In addition, using Western blot and q-PCR, the expression of proteins and genes connected to the NF-κB signaling pathway in mice with lipopolysaccharide (LPS)-induced AKI was found. The findings showed that under AKI intervention in LPS group, ACT group and ISO group, the expression of Rela (Rela gene is responsible for the expression of NFκB p65 protein) and Tlr4 mRNA was considerably elevated (P<0.01), which led to a significant improvement in the expression of MyD88, TLR4, Iκ-Bɑ and NF-κB p65 protein (P<0.001). The levels of Alb, Crea and BUN (P<0.001) increased along with the release of downstream inflammatory factors such as IL-1ß, IL-6, Cys-C, SOD1 and TNF-α (P<0.001). More importantly, the study showed that ISO had a more favorable impact on LPS-induced AKI mice than ACT. In conclusion, by inhibiting NF-κB signaling pathway, ACT and ISO could relieve renal failure and inflammation in AKI, offering a fresh possibility for the therapeutic management of the condition.


Assuntos
Injúria Renal Aguda , Glucosídeos , Inflamação , NF-kappa B , Fenóis , Polifenóis , Transdução de Sinais , Animais , Camundongos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Citocinas/metabolismo , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/patologia , Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Rim/metabolismo , Lipopolissacarídeos , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Fenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Fator de Transcrição RelA/metabolismo , Polifenóis/metabolismo , Polifenóis/uso terapêutico
4.
Zhongguo Zhong Yao Za Zhi ; 47(5): 1286-1292, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35343156

RESUMO

This study discovered that the resolution of 3,5-O-dicaffeoylquinic acid(isochlorogenic acid A) in the content determination method of Chrysanthemi Flos in Chinese Pharmacopoeia(ChP)(2020 edition) was poor, which affected accurate quantification. We tested the method in ChP with chromatographic columns of seven brands to clarify the problems in the existing method, optimized the chromatographic conditions by adjusting the mobile phase composition and elution ratio and replacing the chromatographic column packing, and carried out the reproducibility assay for the new method. The two methods were compared for the content determination results of Chrysanthemi Flos prepared from six different varieties. As evaluated by the resolution based on different chromatographic columns of seven brands, the existing method failed to separate isochlorogenic acid A and isochlorogenic acid D well. The peaks of the two components were not completely separated on three chromatographic columns, and isochlorogenic acid A and isochlorogenic acid D generated a co-effluent peak in the other four columns. Isochlorogenic acid A and isochlorogenic acid D could be completely separated under the optimized chromatographic conditions. The difference in the peak areas of isochlorogenic acid A+isochlorogenic acid D obtained by the optimized method and the method in ChP was not significant, with deviation less than 3.0%, which further proved that the result measured by the method in ChP was the co-effluent of isochlorogenic acid A and isochlorogenic acid D. The optimized method can ensure the accurate quantification of isochlorogenic acid A. The existing content determination method of Chrysanthemi Flos has the problem of poor resolution. It is recommended to revise the chromatographic conditions for the content determination method of Chrysanthemi Flos to improve the resolution of isochlorogenic acid A and ensure its accurate quantification.


Assuntos
Medicamentos de Ervas Chinesas , China , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Flores/química , Reprodutibilidade dos Testes
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