Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Angew Chem Int Ed Engl ; 63(3): e202316839, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014862

RESUMO

Reasonably elevating the working voltage (≥4.4 V vs. Li/Li+ ) of the cathode is one of the efficient approaches to maximize the energy density of lithium-ion batteries (LIBs). As a preferred partner for high-voltage LIB systems, localized high-concentration electrolyte (LHCE), characterized by a stronger Li solvation structure, less free solvent, and robust electrode/electrolyte interphase has attracted much attention in academic circles. Herein, we systematically studied the role of the diluent in LHCE on the formation of the cathode electrolyte interphase (CEI) and elucidated that the existing anion-diluent pairing in the inner Helmholtz plane (IHP) results in an uneven CEI and subsequent battery degradation under high voltage. A m-fluorotoluene (mFT) diluent was further employed in the LHCE containing lithium difluoro(oxalato)borate (LiDFOB) to facilitate a uniform and rich-anion-derived CEI, since the weaker interaction of HmFT -BDFOB - , as compared to the HHhydrofluoroether -BDFOB - , reduces the influence of mFT in IHP or initial CEI formation. Consequently, the mFT-dominated LHCE propels the high-voltage performance of LIBs one step forward, endowing a 4.6 V-class 1.2-Ah graphite||LiNi0.8 Co0.1 Mn0.1 O2 pouch cells a 90.4 % capacity retention after 130 cycles. Our study thus describes a new index affecting the CEI formation and proposes novel strategies to deeply optimize the high-voltage LIBs.

2.
Molecules ; 28(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687212

RESUMO

Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease that has become the third leading cause of death worldwide. Cycloastragenol (CAG), which is the genuine sapogenin of the main active triterpene saponins in Astragali radix, is a bioavailable pre-clinical candidate for chronic obstructive pulmonary disease (COPD), and it was investigated in our previous study. In order to progress medical research, it was first efficiently produced on a 2.5-kg scale via Smith degradation from astragaloside IV (AS-IV). Simultaneously, since the impurity profiling of a drug is critical for performing CMC documentation in pre-clinical development, a study on impurities was carried out. As these structures do not contain chromophores and possess weak UV absorption characteristics, HPLC-CAD and UPLC-LTQ-Orbitrap-MS were employed to carry out the quality control of the impurities. Then, column chromatography (CC), preparative thin-layer chromatography (PTLC), and crystallization led to the identification of 15 impurities from CAG API. Among these impurities, compounds 1, 4, 9, 10, 14, and 15 were elucidated via spectroscopic analysis, and 2-3, 5-8, and 11-13 were putatively identified. Interestingly, the new compounds 9 and 14 were rare 10, 19-secocycloartane triterpenoids that displayed certain anti-inflammatory activities against LPS-induced lymphocyte cells and CSE-induced MLE-12 cells. Additionally, a plausible structural transformation pathway of the degradation compounds from CAG or AS IV was proposed. The information obtained will provide a material basis to carry out the quality control and clinical safety assurance of API and related prescriptions. Reasonable guidance will also be provided regarding the compounds with weak UV absorption characteristics.


Assuntos
Astrágalo , Doença Pulmonar Obstrutiva Crônica , Sapogeninas , Cromatografia Líquida de Alta Pressão , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 2): 122084, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379087

RESUMO

Nanozymes have potential applications in many fields, and a novel copper-containing nanozyme with highly dispersity and uniformity was self-assembled for efficient degradation of various organic dyes in this work. In the nanozyme, histidine was used to coordinate with copper ions, and hydrogen peroxide was prone to Fenton-like reaction to generate hydroxylated copper oxide intermediates. The nanozyme showed good peroxidase-like activity, and also had the ability to catalyze the degradation of various organic dyes efficiently with good storage and recycling ability. Furthermore, the degradation kinetics and mechanism of nanozyme had been further studied, and found that hydroxyl radical and singlet oxygen play vital roles in the catalytic degradation process. Meanwhile, this nanozyme can efficiently degrade two organic compounds at the same time, and this system is capable of dealing with complex practical application scenarios where wastewater contains a variety of organic pollutants.


Assuntos
Cobre , Peróxido de Hidrogênio , Histidina , Corantes , Águas Residuárias
4.
Immunopharmacol Immunotoxicol ; 41(1): 76-85, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30721636

RESUMO

Context: Phillygenin (PHI) is an intestinal metabolite of phillyrin from the genus Forsythia. Although the regulatory activity of Forsythia on immune system has been investigated, the effect of PHI on activated lymphocytes is poorly understood. Objective: This study was aimed to discuss the possible anti-inflammation potential of PHI on mitogen-activated stimulated lymphocytes in vitro. Methods: Mice spleen lymphocytes were incubated with PHI for 4 h, and then stimulated with concanavalin A (Con A) or phorbol 12-myristate 13-acetate/ionomycin (PMA + Ion). Cell viability was assayed by cell counting kit-8 (CCK-8). The expression of CD69 and CD25, proliferation, cell cycle, intracellular Ca2+ concentration, apoptosis, mitochondrial inner membrane potential (ΔΨm), mitochondrial permeability transition (MPT), interleukin-2 (IL-2), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) were analyzed by flow cytometry. The expression of cyclin B1, cyclin D1, Cyclin E, and the phosphorylation of c-jun N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (Erk1/2) and p38 were assayed by western blotting. Results: The results showed that PHI inhibited the proliferation of Con A-activated lymphocytes and induced a G0/G1 phase arrest by suppressing cyclin D1 and cyclin E. Meanwhile, PHI antagonized Con A-induced T cells activation through blocking intracellular Ca2+ overload and suppressing the phosphorylation of JNK and Erk1/2. Both Con A and PMA + Ion-induced secretion of IL-2, IFN-γ, and TNF-α were attenuated by PHI. PHI enhanced Con A-induced lymphocytes apoptosis through decreasing ΔΨm and increasing MPT. Conclusion: These results suggest that PHI exhibits its anti-inflammatory activity through modulating multiple cellular behaviors, leading to the suppression of the adaptive immune response.


Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Lignanas/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Animais , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Células Cultivadas , Citocinas/imunologia , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial
5.
Immunopharmacol Immunotoxicol ; 39(3): 131-139, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28290732

RESUMO

CONTEXT: Cycloastragenol (CAG) is a molecule isolated from various species in the genus Astragalus. Although the regulatory activity of Astragalus on immune system has been investigated, the effect of CAG on activated lymphocytes is poorly understood. OBJECTIVE: We aimed to biologically address the possible anti-inflammation potential of CAG on concanavalin A (Con A)-mediated mouse lymphocyte pan-activation model. MATERIALS AND METHODS: Mouse lymphocytes were obtained from spleens and subjected to Con A for 24 h. Herein, the cells were treated with different concentrations of CAG. Cell viability was assayed by MTT. Pretreated by CAG and stimulated by Con A, the expression of CD69 and CD25, Th1/Th2/Th17 cytokines, cell cycle, proliferation and intracellular Ca2+ concentration ([Ca2+]i) were analyzed by flow cytometry. RESULTS: The results declared that CAG significantly downregulated both CD69 and CD25 expressed on Con A activated CD3 + T cells' surface, as well as inhibiting proliferation of activated lymphocytes. In addition, CAG blocked the Con A-induced mitogenesis, exhibiting lymphocyte G0/G1-phase cell-cycle arrest with significant reduction of cells in S and G2/M phases. Meanwhile, pretreated by CAG, a significant decline in [Ca2+]i was observed. Furthermore, CAG significantly inhibited the production of Th1 cytokines IFN-γ, TNF, IL-2, Th2 cytokines IL-4, IL-6, IL-10 and Th17 cytokine IL-17 A on Con A-activated lymphocytes. CONCLUSION: Our results reinforce that CAG has important anti-inflammatory activity by inhibiting lymphocytes activation, proliferation and cytokines expression, and shows, that this effect may be related to reduction of overall intracellular Ca2+ overload.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Concanavalina A/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Sapogeninas/farmacologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Astrágalo/química , Sinalização do Cálcio/imunologia , Citocinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Sapogeninas/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA