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1.
Sci Rep ; 13(1): 2498, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36781904

RESUMEN

Isorhamnetin (ISO) is a methylated flavonol present in the leaves, flowers, and fruits of many plants with antitumour, anti-inflammatory, antioxidant, and anti-apoptotic properties. ISO has been suggested as the active substance in Vernonia anthelmintica (L.) to treat vitiligo. However, the mechanisms underlying its effects remain unclear. In this study, human keratinocytes (HaCaT cells) were pre-treated with or without ISO and then stimulated with hydrogen peroxide (H2O2) to generate oxidative damage. Pre-treatment with ISO increased HaCaT cell viability, reduced malondialdehyde content, and enhanced superoxide dismutase activity, resulting in a reduction in the loss of mitochondrial membrane potential, improved cell morphological damage, and apoptosis inhibition. Furthermore, we identified 51 significantly dysregulated differentially expressed genes (DEGs) of HaCaT cells treated with ISO using RNA-sequencing. Enrichment analysis using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases indicated that the protective effect of ISO could be related to its effects on the Wnt signalling pathway. Our study provides novel insights into key gene regulation in the progression of oxidative damage and the mechanisms of action of ISO.


Asunto(s)
Células HaCaT , Peróxido de Hidrógeno , Humanos , Peróxido de Hidrógeno/toxicidad , Peróxido de Hidrógeno/metabolismo , Estrés Oxidativo , Quercetina/farmacología , Antioxidantes/farmacología , Antioxidantes/metabolismo , Apoptosis , Supervivencia Celular , Especies Reactivas de Oxígeno/metabolismo
2.
ACS Nano ; 16(7): 11291-11299, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35848713

RESUMEN

The rapid development of spintronics requires the devices to be flexible, to be used in wearable electronics, and controllable, to be used with magnetoelectric (ME) structures. However, the clamping effect inevitably leads to a decreased ME effect on the rigid substrate, and it remains challenging to directly prepare high-quality ferroelectric (FE) membranes on the widely used flexible substrate such as MICA or polyimide (PI). Here, periodic wrinkle-patterned flexible (Co/Pt)5/BaTiO3 (BTO) perpendicular magnetic anisotropy (PMA) heterostructures were prepared using the water-soluble method. The high-quality single-crystal BTO membrane ensures that intricate wrinkles do not fracture and a high ME coefficient is achievable. The transferred sample that is released from the clamping effect shows an enhanced ME effect in both in-plane and out-of-plane directions, with the ME coefficient reaching up to 68 Oe °C-1. The ferromagnetic resonance (FMR) field of the flexible sample can be tuned by tensile strain up to 272 Oe. The finely controlled wrinkle shows periodic strain variations at peak and valley regions that switch the PMA magnetic domain motion as an effective control method. The proposed ultraflexible wrinkle sample shows great potential for combining multiple magnetization tuning approaches, allowing it to potentially serve as a tunable high-density 3D storage prototype.

3.
Chin Med J (Engl) ; 133(4): 444-451, 2020 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-31977550

RESUMEN

BACKGROUND: Pioglitazone may be beneficial in the treatment of psoriasis. However, based on the effectiveness and safety considerations, it has not been widely used. To fully evaluate the strength of evidence supporting psoriasis treatment with pioglitazone, we conducted a meta-analysis of existing published studies. METHODS: PubMed, Ovid, Cochrane Library, Google Scholar, and Web of Science databases were systematically searched before February 2019. Randomized controlled trials (RCTs) of pioglitazone administration compared with placebo, administered to patients with psoriasis for at least 10 weeks, and published in English were included. Quality of the included RCTs was identified by the modified Jadad scale. The quality of evidence for each outcome was evaluated using the GRADEpro Guideline Development Tool online software. Primary outcomes were proportion of patients showing psoriasis area and severity index (PASI) score improvement (>75%) and the mean percent change in PASI score from baseline to the end of treatment. Dichotomous data were analyzed using odds ratios (ORs) corresponding to the 95% confidence interval (CI), whereas continuous variables, expressed as mean and standard deviation, were analyzed using the mean differences (MD) with the 95% CI. RESULTS: Six RCTs were analyzed. Meta-analysis showed that pioglitazone reduced the PASI scores in patients with psoriasis compared with the control group when administered at 30 mg per day (P < 0.001, MD = -3.82, 95% CI = -5.70, -1.93) and at 15 mg per day (P = 0.04, MD = -3.53, 95% CI = -6.86, -0.20). The PASI-75 of the pioglitazone group was significantly higher than that of the control group at 30 mg per day (P < 0.001, OR = 8.30, 95% CI = 3.99, 17.27) and at 15 mg per day (P = 0.03, OR = 2.96, 95% CI = 1.08, 8.06). No statistically significant differences in total adverse events were observed between the groups. There were no significant differences in common adverse reactions such as weight gain and elevated liver enzymes between the two pioglitazone groups. CONCLUSIONS: Use of pioglitazone in the current treatment of psoriasis is beneficial. The therapeutic effect of the daily 30 mg dose may be greater than that of the 15 mg dose per day with no significant change in the frequency of adverse reactions.


Asunto(s)
Pioglitazona/uso terapéutico , Psoriasis/tratamiento farmacológico , Humanos , Pioglitazona/administración & dosificación , Pioglitazona/efectos adversos , Sesgo de Publicación , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad
4.
ACS Appl Mater Interfaces ; 12(7): 8855-8861, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-31984722

RESUMEN

The operation mechanism of giant magnetoresistance (GMR) sensors relies on the linear response of the magnetization direction to an external magnetic field. Since the magnetic anisotropy of ferromagnetic layers can be manipulated by a strain-mediated magnetoelectric coupling effect, we propose a tunable GMR magnetic field sensor design that allows for voltage tuning of the linear range and sensitivity. A spin valve structure Ru/CoFe/Cu/CoFe/IrMn/Ru is grown on a PMN-PT (011) substrate, and the magnetization directions of ferromagnetic layers can be controlled by an electric field. An adjustable linear magnetoresistance is therefore induced. Based on the magnetoelectric coupling effect and spin valve, we prepared tunable GMR magnetic field sensors with bridge structures. The linear sensing range of a DC magnetic field is enhanced 6 times by applying an electric field of 14 kV/cm. The electrically tunable GMR sensor fulfills the requirements to work at different magnetic field ranges in the same configuration, therefore exhibiting great potential for applications in the Internet of things.

5.
ACS Nano ; 12(4): 3751-3758, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29498510

RESUMEN

Traditional magnetostrictive/piezoelectric laminated composites rely on the two-dimensional interface that transfers stress/strain to achieve the large magnetoelectric (ME) coupling, nevertheless, they suffer from the theoretical limitation of the strain effect and of the substrate clamping effect in real ME applications. In this work, 3D NZFO/BTO-pillar nanocomposite films were grown on SrTiO3 by template-assisted pulsed laser deposition, where BaTiO3 (BTO) nanopillars appeared in an array with distinct phase transitions as the cores were covered by NiZn ferrite (NZFO) layer. The perfect 3D heteroepitaxial interface between BTO and NZFO phases can be identified without any edge dislocations, which allows effective strain transfer at the 3D interface. The 3D structure nanocomposites enable the strong two magnon scattering (TMS) effect that enhances ME coupling at the interface and reduces the clamping effect by strain relaxation. Thereby, a large FMR field shift of 1866 Oe in NZFO/BTO-pillar nanocomposite was obtained at the TMS critical angle near the BTO nanopillars phase transition of 255 K.

6.
Adv Mater ; : e1802902, 2018 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-30109765

RESUMEN

The voltage modulation of yttrium iron garnet (YIG) is of practical and theoretical significance; due to its advantages of compactness, high-speed response, and energy efficiency, it can be used for various spintronic applications, including spin-Hall, spin-pumping, and spin-Seebeck effects. In this study, a significant ferromagnetic resonance change is achieved within the YIG/Pt bilayer heterostructures uisng ionic modulation, which is accomplished by modifying the interfacial magnetism in the deposited "capping" platinum layer. With a small voltage bias of 4.5 V, a large ferromagnetic field shift of 690 Oe is achieved in heterostructures of YIG (13 nm)/Pt (3 nm)/(ionic liquid, IL)/(Au capacitor). The remarkable magnetoelectric (ME) tunability comes from the additional and voltage-induced ferromagnetic ordering, caused by uncompensated d-orbital electrons in the Pt metal layer. Confirmed by first-principle calculations, this finding paves the way for novel voltage-tunable YIG-based spintronics.

7.
ACS Appl Mater Interfaces ; 9(36): 30733-30740, 2017 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-28810124

RESUMEN

Yttrium iron garnet (YIG) is of great importance in RF/microwave devices for its low loss, low intrinsic damping, and high permeability. Nevertheless, tuning of YIG-based multiferroics is still a challenge due to its near-zero magnetostriction and the difficulty of building epitaxial interface between ferromagnetic garnet and ferroelectric perovskite phases. In this work, the vertically aligned heterostructure of YIG:BTO/STO(001) with local epitaxial interface between BTO and YIG is well-constructed, where the single crystal BTO pillars are embedded in YIG matrix. A large magnetoelectric coupling effect that drives YIG's FMR shift up to 512 and 333 Oe (1-2 order greater than those of all state-of-the-art progresses) is obtained through BTO ferroelectric phase changes induced by temperature variation at 295 and 193 K, correspondingly. This record high magnetoelectric tunability of YIG paves a way toward thermal/electrical tunable YIG devices.

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