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.
J Am Chem Soc ; 144(13): 5841-5854, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35333056

RESUMO

Electrode materials for Li+-ion batteries require optimization along several disparate axes related to cost, performance, and sustainability. One of the important performance axes is the ability to retain structural integrity though cycles of charge/discharge. Metal-metal bonding is a distinct feature of some refractory metal oxides that has been largely underutilized in electrochemical energy storage, but that could potentially impact structural integrity. Here LiScMo3O8, a compound containing triangular clusters of metal-metal bonded Mo atoms, is studied as a potential anode material in Li+-ion batteries. Electrons inserted though lithiation are localized across rigid Mo3 triangles (rather than on individual metal ions), resulting in minimal structural change as suggested by operando diffraction. The unusual chemical bonding allows this compound to be cycled with Mo atoms below a formally +4 valence state, resulting in an acceptable voltage regime that is appropriate for an anode material. Several characterization methods including potentiometric entropy measurements indicate two-phase regions, which are attributed through extensive first-principles modeling to Li+ ordering. This study of LiScMo3O8 provides valuable insights for design principles for structural motifs that stably and reversibly permit Li+ (de)insertion.

2.
Naunyn Schmiedebergs Arch Pharmacol ; 394(5): 955-965, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33404687

RESUMO

Lithium (Li) represents a first choice mood stabilizer for bipolar disorder (BD). Despite extensive clinical use, questions regarding its mechanism of action and pathological mechanism of renal function impairment by Li remain open. The present study aimed to improve our knowledge in this area paying special attention to the relationship between the length of Li action, lipid peroxidation (LP), and Na+/K+-ATPase properties. The effects of therapeutic Li doses, administered daily to male Wistar rats for 1 (acute), 7 (short term) and 28 days (chronic), were studied. For this purpose, Na+/K+-ATPase activity measurements, [3H]ouabain binding and immunoblot analysis of α-Na+/K+-ATPase were performed. Li-induced LP was evaluated by determining the malondialdehyde concentration by HPLC. Sleep deprivation (SD) was used as an experimental approach to model the manic phase of BD. Results obtained from the kidney were compared to those obtained from erythrocytes and different brain regions in the same tested animals. Whereas treatment with therapeutic Li concentration did not bring any LP damage nor significant changes of Na+/K+-ATPase expression and [3H]ouabain binding in the kidney, it conferred strong protection against this type of damage in the forebrain cortex. Importantly, the observed changes in erythrocytes indicated changes in forebrain cortices. Thus, different resistance to SD-induced changes of LP and Na+/K+-ATPase was detected in the kidney, erythrocytes and the brain of Li-treated rats. Our study revealed the tissue-specific protective properties of Li against LP and Na+/K+-ATPase regulation.


Assuntos
Antimaníacos/farmacologia , Transtorno Bipolar/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Carbonato de Lítio/farmacologia , Animais , Antimaníacos/administração & dosagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Carbonato de Lítio/administração & dosagem , Masculino , Ratos , Ratos Wistar , Privação do Sono/psicologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Fatores de Tempo
3.
Artigo em Inglês | MEDLINE | ID: mdl-32360816

RESUMO

Lithium (Li) is a typical mood stabilizer and the first choice for treatment of bipolar disorder (BD). Despite an extensive clinical use of Li, its mechanisms of action remain widely different and debated. In this work, we studied the time-course of the therapeutic Li effects on ouabain-sensitive Na+/K+-ATPase in forebrain cortex and hippocampus of rats exposed to 3-day sleep deprivation (SD). We also monitored lipid peroxidation as malondialdehyde (MDA) production. In samples of plasma collected from all experimental groups of animals, Li concentrations were followed by ICP-MS. The acute (1 day), short-term (7 days) and chronic (28 days) treatment of rats with Li resulted in large decrease of Na+/K+-ATPase activity in both brain parts. At the same time, SD of control, Li-untreated rats increased Na+/K+-ATPase along with increased production of MDA. The SD-induced increase of Na+/K+-ATPase and MDA was attenuated in Li-treated rats. While SD results in a positive change of Na+/K+-ATPase, the inhibitory effect of Li treatment may be interpreted as a pharmacological mechanism causing a normalization of the stress-induced shift and return the Na+/K+-ATPase back to control level. We conclude that SD alone up-regulates Na+/K+-ATPase together with increased peroxidative damage of lipids. Chronic treatment of rats with Li before SD, protects the brain tissue against this type of damage and decreases Na+/K+-ATPase level back to control level.


Assuntos
Antimaníacos/farmacologia , Hipocampo/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Carbonato de Lítio/farmacologia , Prosencéfalo/efeitos dos fármacos , Prosencéfalo/metabolismo , Privação do Sono/tratamento farmacológico , Privação do Sono/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Antimaníacos/uso terapêutico , Ligação Competitiva/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Malondialdeído/metabolismo , Ouabaína/metabolismo , Prosencéfalo/enzimologia , Ratos , Ratos Wistar , Privação do Sono/enzimologia
4.
J Neuroimmunol ; 341: 577191, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113006

RESUMO

Morphine- and Concanavalin A-induced changes of protein composition of rat spleen lymphocytes were determined by high-resolution proteomic analysis, gel-free, label-free quantification, MaxLFQ. Stimulation by Con A resulted in a major reorganization of spleen cell protein composition evidenced by increased expression level of 94 proteins; 101 proteins were down-regulated (>2-fold). Interestingly, among proteins that were up-regulated to the largest extent were the prototypical brain proteins as a neuron specific enolase, synapsin-1, brain acid-soluble protein-1 and myelin basic protein. Morphine-induced change was limited to no more than 5 up-regulated and 18 down-regulated proteins (>2-fold).


Assuntos
Concanavalina A/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Morfina/farmacologia , Proteoma/efeitos dos fármacos , Proteômica/métodos , Baço/citologia , Animais , Perfilação da Expressão Gênica , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/genética , Linfócitos/metabolismo , Masculino , Ratos , Ratos Wistar
5.
Philos Trans A Math Phys Eng Sci ; 377(2152): 20190020, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31280717

RESUMO

Intercalation compounds are popular candidate electrode materials for sodium-ion batteries and other 'beyond lithium-ion' technologies including potassium- and magnesium-ion batteries. We summarize first-principles efforts to elucidate the behaviour of such compounds in the layered and spinel structures. Trends based on the size and valence of the intercalant and the ionicity of the host are sufficient to explain phase stability and ordering phenomena, which in turn determine the equilibrium voltage profile. For the layered structures, we provide an overarching view of intercalant orderings in prismatic coordination based on antiphase boundaries, which has important consequences for diffusion. We examine details of stacking sequence transitions between different layered structures by calculating stacking fault energies and discussing the nature of dislocations. A better understanding of these transitions will likely aid the development of batteries with improved cyclability. This article is part of a discussion meeting issue 'Energy materials for a low carbon future'.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA