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1.
Nat Commun ; 15(1): 6109, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030195

RESUMO

The collective modes of the superconducting order parameter fluctuation can provide key insights into the nature of the superconductor. Recently, a family of superconductors has emerged in non-magnetic kagome materials AV3Sb5 (A = K, Rb, Cs), exhibiting fertile emergent phenomenology. However, the collective behaviors of Cooper pairs have not been studied. Here, we report a distinct collective mode in CsV3-xTaxSb5 using scanning tunneling microscope/spectroscopy. The spectral line-shape is well-described by one isotropic and one anisotropic superconducting gap, and a bosonic mode due to electron-mode coupling. With increasing x, the two gaps move closer in energy, merge into two isotropic gaps of equal amplitude, and then increase synchronously. The mode energy decreases monotonically to well below 2 Δ and survives even after the charge density wave order is suppressed. We propose the interpretation of this collective mode as Leggett mode between different superconducting components or the Bardasis-Schrieffer mode due to a subleading superconducting component.

2.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5617-5626, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36471980

RESUMO

Laportea bulbifera extract is effective in resisting inflammation and shows a good therapeutic effect on rheumatoid arthritis in rats. However, the absorption characteristics of active components in L. bulbifera extract in Caco-2 cells are still unclear, which limits the in-depth development of L. bulbifera resources. The purpose of this study was to investigate the absorption and transport mechanism of the active components of L. bulbifera extract in the Caco-2 cell model and explore the effects of different factors(concentration, time, pH value, temperature, and efflux transporter inhibitor) on its uptake and transport. The results showed that L. bulbifera extract at the concentration of 2.0-8.0 mg·mL~(-1) showed no toxicity to Caco-2 cells. The uptake and transport of L. bulbifera extract in the Caco-2 cell model were concentration-dependent and time-dependent. The main absorption mechanism was passive diffusion, and acidic condition(pH 5.0-6.0) and 37 ℃ were more favorable for drug absorption. P_(app)>1.0×10~(-6 )cm·s~(-1) of each component indicated that L. bulbifera was a moderately absorbed drug. P-gp, MRP2, and BCRP were not involved in its uptake and transport.


Assuntos
Absorção Intestinal , Urticaceae , Humanos , Ratos , Animais , Células CACO-2 , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Neoplasias/metabolismo , Transporte Biológico , Extratos Vegetais/farmacologia
3.
Zhongguo Zhong Yao Za Zhi ; 45(11): 2626-2633, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-32627498

RESUMO

This study aims to reveal the pharmacokinetics of Shuganning Injection in normal rats. In this experiment,ultra-high performance liquid chromatography-electrospray-tandem mass spectrometry( UPLC-ESI-MS/MS) was used to establish an analytical method for simultaneous determination of chlorogenic acid,gardenioside,oroxylin A and baicalin in rat plasma. Then,the non-compartmental model( NCA) in Phoenix WinN onL in 6. 4 software was used to fit pharmacokinetic parameters. The methodological validation showed that the linear relationship of the components in rat plasma samples were good( r>0. 995). The recovery rate and matrix effect of plasma samples with low,middle and high concentration were 79. 14%-101. 4%. The intra-day and inter-day precision,accuracy and stability meet the requirements of biological sample analysis. The half-life( t1/2) of chlorogenic acid,gardenioside,oroxylin A did not change significantly and the area under blood concentration-time curve( AUC0-t) is proportional to the dose,which suggested that three components showed a linear kinetic characteristics,but baicalin showed nonlinear kinetic characteristics. Moreover,the retention time of each component in rats was short. The established UPLC-MS/MS quantitative analysis method is rapid,sensitive and accurate,which can be used for the determination of chlorogenic acid,gardenioside,oroxylin A and baicalin in rat plasma and pharmacokinetic study of Shuganning Injection.


Assuntos
Plasma , Espectrometria de Massas em Tandem , Animais , Ácido Clorogênico , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
4.
Artigo em Inglês | MEDLINE | ID: mdl-32595724

RESUMO

Eucommiae Cortex (EC), a rare, nourishing medicinal herb that is native in China, has good effect in the treatment of hypertension. In this study, we compared tissue distribution of six representative active components of EC extract-genipinic acid (GA), protocatechuic acid (PCA), neochlorogenic acid (NCA), chlorogenic acid (CA), (+)-pinoresinol di-O-ß-D-glucopyranoside (PDG), and (+)-pinoresinol 4'-O-ß-D-glucopyranoside (PG)-between normal rats and spontaneously hypertensive rats (SHRs). Each rat was intragastrically given EC extract at a dose of 5.4 g/kg. Rats were sacrificed at 10 min, 30 min, 2 h, and 8 h after administration; six rats were sacrificed at each time point. Then, we quickly harvested their major organs, including heart, liver, spleen, lungs, kidneys, and brain. Using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), we determined the levels of the above mentioned six components in the organs of both types of rats and then analyzed differences in the tissue distribution. The results showed that levels of each component differed between SHRs and the normal group at each time point. As time progressed, the number of organs in which GA distribution in each tissue of SHRs differed from that of the normal group gradually increased: SHRs showed lower GA levels than normal rats. Levels of PG and PDG in both groups at 10 and 30 min were similar. NCA and CA in the SHR group and the normal group at 10 min, 30 min, and 2 h were also similar to some extent. The results indicated that the pathological state of spontaneous hypertension could affect tissue distribution of EC active components in rats.

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