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1.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38953451

RESUMO

Inspired by biological channels, achieving precise separation of ion/water and ion/ion requires finely tuned pore sizes at molecular dimensions and deliberate exposure of charged groups. Covalent organic frameworks (COFs), a class of porous crystalline materials, offer well-defined nanoscale pores and diverse structures, making them excellent candidates for nanofluidic channels that facilitate ion and water transport. In this study, we perform molecular simulations to investigate the structure and kinetics of water and ions confined within the typical COFs with varied exposure of charged groups. The COFs exhibit vertically arrayed nanochannels, enabling diffusion coefficients of water molecules within COFs to remain within the same order of magnitude as in the bulk. The motion of water molecules manifests in two distinct modes, creating a mobile hydration layer around acid groups. The ion diffusion within COFs displays a notable disparity between monovalent (M+) and divalent (M2+) cations. As a result, the selectivity of M+/M2+ can exceed 100, while differentiation among M+ is less pronounced. In addition, our simulations indicate a high rejection (R > 98%) in COFs, indicating their potential as ideal materials for desalination. The chemical flexibility of COFs indicates that would hold significant promise as candidates for advanced artificial ion channels and separation membranes.

2.
J Cell Mol Med ; 23(11): 7651-7663, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31565849

RESUMO

Diabetic cardiomyopathy is characterized by diabetes-induced myocardial abnormalities, accompanied by inflammatory response and alterations in inflammation-related signalling pathways. Kirenol, isolated from Herba Siegesbeckiae, has potent anti-inflammatory properties. In this study, we aimed to investigate the cardioprotective effect of kirenol against DCM and underlying the potential mechanisms in a type 2 diabetes mellitus model. Kirenol treatment significantly decreased high glucose-induced cardiofibroblasts proliferation and increased the cardiomyocytes viability, prevented the loss of mitochondrial membrane potential and further attenuated cardiomyocytes apoptosis, accompanied by a reduction in apoptosis-related protein expression. Kirenol gavage could affect the expression of pro-inflammatory cytokines in a dose-dependent manner but not lower lipid profiles, and only decrease fasting plasma glucose, fasting plasma insulin and mean HbA1c levels in high-dose kirenol-treated group at some time-points. Left ventricular dysfunction, hypertrophy, fibrosis and cell apoptosis, as structural and functional abnormalities, were ameliorated by kirenol administration. Moreover, in diabetic hearts, oral kirenol significantly attenuated activation of mitogen-activated protein kinase subfamily and nuclear translocation of NF-κB and Smad2/3 and decreased phosphorylation of IκBα and both fibrosis-related and apoptosis-related proteins. In an Electrophoretic mobility shift assay, the binding activities of NF-κB, Smad3/4, SP1 and AP-1 in the nucleus of diabetic myocardium were significantly down-regulated by kirenol treatment. Additionally, high dose significantly enhanced myocardial Akt phosphorylation without intraperitoneal injection of insulin. Kirenol may have potent cardioprotective effects on treating for the established diabetic cardiomyopathy, which involves the inhibition of inflammation and fibrosis-related signalling pathways and is independent of lowering hyperglycaemia, hyperinsulinemia and lipid profiles.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Diterpenos/uso terapêutico , Inflamação/tratamento farmacológico , Animais , Biomarcadores/metabolismo , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno/biossíntese , Citocinas/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Cardiomiopatias Diabéticas/sangue , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Diterpenos/administração & dosagem , Diterpenos/química , Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Glucose/toxicidade , Inflamação/sangue , Inflamação/complicações , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Inibidor de NF-kappaB alfa/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Proteínas Smad/metabolismo , Remodelação Ventricular/efeitos dos fármacos
3.
Angew Chem Int Ed Engl ; 56(27): 7769-7773, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28467678

RESUMO

Cobalt-based nanomaterials have been intensively explored as promising noble-metal-free oxygen evolution reaction (OER) electrocatalysts. Herein, we report phase-selective syntheses of novel hierarchical CoTe2 and CoTe nanofleeces for efficient OER catalysts. The CoTe2 nanofleeces exhibited excellent electrocatalytic activity and stablity for OER in alkaline media. The CoTe2 catalyst exhibited superior OER activity compared to the CoTe catalyst, which is comparable to the state-of-the-art RuO2 catalyst. Density functional theory calculations showed that the binding strength and lateral interaction of the reaction intermediates on CoTe2 and CoTe are essential for determining the overpotential required under different conditions. This study provides valuable insights for the rational design of noble-metal-free OER catalysts with high performance and low cost by use of Co-based chalcogenides.

4.
Zhongguo Zhong Yao Za Zhi ; 41(11): 2070-2080, 2016 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28901103

RESUMO

To explore the processing mechanism of Aurantii Fructus decoction pieces used in Guangdong province and Hong Kong by analysing the chemical variation between raw and processed Aurantii Fructus with different methods based on UHPLC-Q-TOF-MS. The total ion chromatograms detected in positive and negative ion modes, and ion peak area ratio before and after processing were taken as variation indexes in the comparison. The results indicated that fermented Aurantii Fructus could produce three new ingredients, namely eriodictyol-7-glucoside, hesperetin-7-O-glucoside and 5-demethylnobiletin. At the same time, it could significantly increase the content of naringenin and hesperetin components, and could increase the content of such limonin derivatives as sudachinoid A, obacunoic acid and limoninand nomilinic acid. This suggests that the fermentation processing method of Aurantii Fructus decoction pieces used in Guangdong province and Hong Kong is of important significance for enhancing biological activity and bioavailability, and improving the clinical efficacy of Aurantii Fructus decoction pieces, and so is worth further protection and promotion.


Assuntos
Citrus/química , Medicamentos de Ervas Chinesas/química , Flavonas/análise , Glucosídeos/análise , Cromatografia Líquida de Alta Pressão , Frutas/química , Espectrometria de Massas
5.
Zhong Yao Cai ; 36(9): 1457-63, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24620694

RESUMO

OBJECTIVE: To analyze the volatile components of Platycladus orientalis extracted by headspace solid phase microextraction (HS-SPME) and steam distillation-extraction (DSE). METHODS: The volatile components which were extracted by DSE and analyzed by GC-MS; The HS-SPME conditions was optimized, and the volatile components were analyzed by GC-MS. RESULTS: Sixty-two kinds of volatile components extracted by DSE were isolated and 50 of them were identified; Sixty-eight kinds of volatile components extracted by HS-SPME were isolated and 67 of them were identified. CONCLUSION: Compared with DSE,HS-SPME has higher retrieval matching and sensitivity, which is more suitable for the analysis of the volatile components of P. orientalis.


Assuntos
Cupressaceae/química , Medicamentos de Ervas Chinesas/química , Microextração em Fase Sólida/métodos , Vapor , Compostos Orgânicos Voláteis/análise , Destilação , Medicamentos de Ervas Chinesas/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Folhas de Planta/química , Caules de Planta/química , Reprodutibilidade dos Testes , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Volatilização
6.
J Ethnopharmacol ; 189: 22-30, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27184188

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE AND AIM OF THE STUDY: Guang-Pheretima, the live form of the earthworm Pheretima aspergillum, is a traditional Chinese medicine commonly used for the treatment of asthma, cough, stroke, epilepsy and other diseases due to its anti-inflammatory, anti-asthmatic, anti-seizure, thrombolytic and diuretic properties. Although Guang-Pheretima is effective in the relief of asthma, its pharmacological activity and the underlying molecular mechanisms are not fully understood. Hence, we investigated the effects of a Pheretima aspergillum decoction (PAD) against inflammation in a model of ovalbumin (OVA)-induced asthma in BALB/c mice, as well as the nuclear factor-κB (NF-κB) pathway involved in this process. MATERIALS AND METHODS: OVA was used to sensitize and challenge the airway of the mice, and PAD was administrated by gavage. We measured airway hyperresponsiveness (AHR) in the mice 24h following a final methacholine challenge with whole-body plethysmography. The bronchoalveolar lavage fluid (BALF), serum and pulmonary tissues were collected 48h after the last challenge. The levels of inflammatory factors and the related mRNAs were determined by enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR), respectively. The number of differential inflammatory cells in the BALF was counted. Serum total and OVA-specific IgE levels were measured with ELISA. The activation of NF-κB signaling in the lung was detected by western blotting. In addition, the lung tissues were stained with hematoxylin and eosin or periodic acid Schiff stain for histopathological examination. RESULTS: PAD treatment significantly alleviated AHR in the asthmatic mice, decreased the mRNA and protein levels of IL-4, IL-5 and IL-13 and downregulated IgE. In addition, PAD treatment attenuated mucus secretion and infiltration of inflammatory cells in the lung while inhibiting the activation of NF-κB signaling. CONCLUSIONS: PAD effectively inhibited the activation of NF-κB signaling in the lungs of mice with OVA-induced asthma, and mitigated AHR and Th2 type inflammatory reactions. Therefore, PAD may serve as a drug candidate for asthma treatment.


Assuntos
Antiasmáticos/farmacologia , Anti-Inflamatórios/farmacologia , Asma/tratamento farmacológico , Brônquios/efeitos dos fármacos , Hiper-Reatividade Brônquica/tratamento farmacológico , Broncoconstrição/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Oligoquetos/química , Extratos de Tecidos/farmacologia , Animais , Antiasmáticos/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Asma/sangue , Asma/imunologia , Asma/fisiopatologia , Brônquios/imunologia , Brônquios/metabolismo , Brônquios/fisiopatologia , Hiper-Reatividade Brônquica/sangue , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Imunoglobulina E/sangue , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Ovalbumina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Células Th2/imunologia , Células Th2/metabolismo , Fatores de Tempo , Extratos de Tecidos/isolamento & purificação
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