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1.
J Colloid Interface Sci ; 664: 511-519, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38484519

RESUMEN

The conversion-type anode material of iron phosphide (FeP) promises enormous prospects for Na-ion battery technology due to its high theoretical capacity and cost-effectiveness. However, the poor reaction kinetics and large volume expansion of FeP significantly degrade the sodium storage, which remains a daunting challenge. Herein, we demonstrate a binder-free nanotube array architecture constructed by FeP@C hybrid on carbon cloth as advanced anodes to achieve fast and stable sodium storage. The nanotubular structure functions in multiple roles of providing short electron/ion transport distances, smooth electrolyte diffusion channels, and abundant active sites. The carbon layer could not only pave high-speed pathways for electron conductance but also cushion the volume change of FeP. Benefiting from these structural virtues, the FeP@C anode receives a high reversible capacity of 881.7 mAh/g at 0.1 A/g, along with a high initial Coulombic efficiency of 90% and excellent rate capability and cyclability in half and full cells. Moreover, the sodium energy reaction kinetics and mechanism of FeP@C are systematically studied. The present work offers a rational design and construction of high-capacity anode materials for high-energy-density Na-ion batteries.

2.
Fitoterapia ; 138: 104342, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31479703

RESUMEN

Cordyceps militaris (L.) Link (C. militaris) has been used as a folk medicine for treatment of various diseases in China and some other countries. Recent evidence suggests that aqueous extracts of C. militaris have hypoglycemic activity. So the aim of this study was to isolate and characterize compounds with aiti-PTP1B (protein tyrosine phosphatase 1B) activity from C. militaris. As a result, cordycerebroside B (1) together with other three known cerebrosides (2-4) and a disaccharide (5) were isolated by silica gel column chromatography and semi-preparative high performance liquid chromatography (HPLC) and then elucidated on the basis of 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy (MS) and chemical method. Among of which, cordycerebroside B was a new compound and isolated from C. militaris for the first time. The results of the activity assays demonstrated that all these four cerebrosides (compounds 1-4) showed marked inhibition activity against PTP1B with IC50 values of 4.68 ±â€¯0.18, 16.93 ±â€¯1.08, 10.43 ±â€¯0.64 and 18.92 ±â€¯1.65 µM. All the compounds had no discernible cytotoxicity for Rat pheochromocytoma (PC12 cells). These findings suggested that C. militaris or its cerebrosides may be considered as potential useful therapeutic agents for type 2 diabetes.


Asunto(s)
Cerebrósidos/farmacología , Cordyceps/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Animales , Cerebrósidos/aislamiento & purificación , China , Cuerpos Fructíferos de los Hongos/química , Estructura Molecular , Células PC12 , Ratas , Pruebas de Toxicidad
3.
Front Pharmacol ; 9: 393, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29740319

RESUMEN

The balance and smooth shift between flexible, goal-directed behaviors and repetitive, habitual actions are critical to optimal performance of behavioral tasks. The striatum plays an essential role in control of goal-directed versus habitual behaviors through a rich interplay of the numerous neurotransmitters and neuromodulators to modify the input, processing and output functions of the striatum. The adenosine receptors (namely A2AR and A1R), with their high expression pattern in the striatum and abilities to interact and integrate dopamine, glutamate and cannabinoid signals in the striatum, may represent novel therapeutic targets for modulating instrumental behavior. In this study, we examined the effects of pharmacological blockade of the A2ARs and A1Rs on goal-directed versus habitual behaviors in different information processing phases of instrumental learning using a satiety-based instrumental behavior procedure. We found that A2AR antagonist acts at the coding, consolidation and expression phases of instrumental learning to modulate animals' sensitivity to goal-directed valuation without modifying action-outcome contingency. However, pharmacological blockade and genetic knockout of A1Rs did not affect acquisition or sensitivity to goal-valuation of instrumental behavior. These findings provide pharmacological evidence for a potential therapeutic strategy to control abnormal instrumental behaviors associated with drug addiction and obsessive-compulsive disorder by targeting the A2AR.

4.
Biomed Res Int ; 2018: 3674906, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30596088

RESUMEN

Female reproductive system diseases caused by exposure to a cold environment are widely considered as important human health challenges. Although the projection of female reproduction in cold temperature has been studied, a holistic view on the probable effects of cold exposure on the functions of the female reproductive system has not been achieved. Our aim was to evaluate the effects of cold exposure to the functions of the ovary and uterus in female rats. For this purpose, female rats were randomly grouped as follows: (1) the cold group was exposed to -10°C, 4 h per day for 2 weeks, and (2) the normal temperature (23 ± 1°C) group was used as control. Alterations were observed in different parameters, including body weight gain, organ coefficients, estrus cycle, and pathology of the cold-exposed female rats. Similarly, the serum reproductive hormones and mRNA expression were evaluated. Cold exposure induced estrus cycle irregularity and some alterations in the morphology of the ovary. Cold exposure impairs the function of the ovary probably by changing the level of serum LH and increasing LHR expression. Cold exposure induced a significant reduction of uterine epithelium height. Cold exposure causes alterations in the morphology of the uterus probably because of the effect of progesterone, the increase in the PR level, and the decrease in the ER level.


Asunto(s)
Reproducción/fisiología , Animales , Frío , Estradiol/metabolismo , Femenino , Hormona Luteinizante/metabolismo , Tamaño de los Órganos/fisiología , Ovario/metabolismo , Ovario/fisiología , Progesterona/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de HL/metabolismo , Útero/metabolismo , Útero/fisiología
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