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1.
Nanotechnology ; 34(6)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36252529

RESUMO

To carry out effective resource reforming of sustainable electricity, hydrogen production by electrochemical water splitting provides an eco-friendly and economical way. Nevertheless, the oxygen evolution reaction (OER) at the anode is limited by the slow reaction process, which hinders the large-scale development and application of electrolysis technology. In this work, we present an electrocatalyst with superior OER performance, which attributed to the abundant active sites and good electronic conductivity. The two-dimensional CoMo Layered Double Hydroxide nanosheets are synthesized and deposited on conductive carbon nanotubes (CoMo LDH/CNTs), and then hybrid composites show better catalytic performance than their undecorated counterpart under identical conditions. Specifically, CoMo LDH/CNTs exhibit the low overpotential of 268 mV to obtain 10 mA cm-2and satisfactory stability (more than 40 h). We emphasize that this hybridization strategy with a conductive supporting framework could design more abundant and low-cost OER electrocatalysts to minimize electrical energy consumption, thereby achieving efficient conversion between energy sources.

2.
Am J Transl Res ; 10(5): 1511-1521, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887964

RESUMO

The number of patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) has shown a significant upward trend in recent years. However, antiviral drugs are not very effective. Regulation of liver regeneration by traditional Chinese medicine is an important way to improve clinical efficacy. This randomized controlled trial assessed the efficacy and safety of DWYG in patients with HBeAg-negative CHB. Overall, 130 subjects were randomized to (A) DWYG 1.2 g three times daily (n = 44), (B) entecavir 0.5 mg/day (n = 43) in combination with DWYG or (C) entecavir 0.5 mg/day (n = 43). The liver histological response rate was assessed as the primary efficacy endpoint. The results showed that the liver histological response rate in the combination treatment group was significantly higher than that in the group with entecavir (71.43% versus 22.22%; P = 0.036) after 48 weeks of treatment. And the pathological progression rate of liver in the group with DWYG was significantly lower than that of the entecavir group during 228 weeks of follow-up (0% versus 60.00%; P = 0.019). No significant adverse events occurred during the study. In conclusion, treating HBeAg-negative CHB with DWYG is safe and effective to improve liver histological response.

3.
Proc Natl Acad Sci U S A ; 113(50): 14195-14200, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27911786

RESUMO

Frank-Kasper (F-K) and quasicrystal phases were originally identified in metal alloys and only sporadically reported in soft materials. These unconventional sphere-packing schemes open up possibilities to design materials with different properties. The challenge in soft materials is how to correlate complex phases built from spheres with the tunable parameters of chemical composition and molecular architecture. Here, we report a complete sequence of various highly ordered mesophases by the self-assembly of specifically designed and synthesized giant surfactants, which are conjugates of hydrophilic polyhedral oligomeric silsesquioxane cages tethered with hydrophobic polystyrene tails. We show that the occurrence of these mesophases results from nanophase separation between the heads and tails and thus is critically dependent on molecular geometry. Variations in molecular geometry achieved by changing the number of tails from one to four not only shift compositional phase boundaries but also stabilize F-K and quasicrystal phases in regions where simple phases of spheroidal micelles are typically observed. These complex self-assembled nanostructures have been identified by combining X-ray scattering techniques and real-space electron microscopy images. Brownian dynamics simulations based on a simplified molecular model confirm the architecture-induced sequence of phases. Our results demonstrate the critical role of molecular architecture in dictating the formation of supramolecular crystals with "soft" spheroidal motifs and provide guidelines to the design of unconventional self-assembled nanostructures.

4.
Zhongguo Zhong Yao Za Zhi ; 39(13): 2498-503, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25276971

RESUMO

Astragali Radix was firstly recorded in the "Shen Nong's Herbal Classic" as a top-grade and commonly used traditional Chinese medicine. Its frequently used slices include raw Astragali Radix and honey-processed products. In current studies, many reports were made on honey-processed Astragali Radix, whereas fewer study reports were made on the cutting process of Astragali Radix. Currently, because Astragali Radix is primarily cut by drug workers according to their operating experience, but with out specific cutting parameters, it is easy to cause the loss or mildew of active ingredients. As a result, the quality of Astragali Radix circulated in the market is not guaranteed, and the quality of their slices and preparations are hard to be controlled, which seriously impact the clinical efficacy. In response, this experiment was performed, in which the optimum cutting process of Astragali Radix was taken as the study objective, the Box-Benhnken central composite design in the response surface analysis was adopted, and the content and appearance character of astragaloside and calycosin-7-glucoside were regarded as the study indicators. Three factors, namely the softening time, the drying temperature and the drying time, were selected to optimize the cutting process of Astragali Radix and obtain the optimum cutting process parameters as follows: the softening time was 3 hours, the drying temperature was 50 degrees C, and the drying time was 4 hours. According to the verification test, the Astragali Radix cutting process is steady and feasible, which has certain significance for normalizing the cutting process of Astragali Radix.


Assuntos
Astrágalo/química , Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão , Glucosídeos/química , Raízes de Plantas/química
5.
Yao Xue Xue Bao ; 49(6): 938-41, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25212044

RESUMO

This study is to report the establishment of an UPLC-MS/MS method for the determination of plasma concentration of UA carried in self-microemulsifying drug delivery system (SMEDDS) and its pharmacokinetics in rats. It was used for determination and analysis when serum with internal standard was extracted from C18 solid-phase column. Acquity UPLC BEH C18 column (100 mm x 2.1 mm, 1.7 microm) was used for separation. The mobile phase was acetonitrile -0.1% ammonia with gradient elution at the flow rate of 0.2 mL x min(-1). The column temperature was 40 degrees C and the detection wave length was 210 nm. It was detected by negative ion using electrospray ionization source (ESI) and scanned by multiple reaction ion monitoring (MRM) mode. The liner relationship of UA was very good in the range of 1.19-3 815.00 ng x mL(-1) (r = 0.999 0). Recovery rate of different concentrations were 87.42%-89.95%. The precision of inter-day and intra-day were less than 11%. The method developed in our study was proved to be sensitive, rapid and simple. It is suitable for the pharmacokinetic study of UA-SMEDDS in rats.


Assuntos
Sistemas de Liberação de Medicamentos , Triterpenos/sangue , Triterpenos/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão , Emulsões/química , Ratos , Espectrometria de Massas em Tandem , Ácido Ursólico
6.
Zhongguo Zhong Yao Za Zhi ; 38(24): 4314-8, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24791537

RESUMO

To optimize the Scutellaria baicalensis extraction process, the filter paper method and the bacteriostatic ratio method were adopted to determine the in vitro bacteriostatic efficacy of water extracts and 60% alcohol extracts from S. baicalensis. The quantitative analysis of multi-components by single-marker (QAMS) was used to determined the contents of four active components, baicalin, wogonoside, baicalein and wogonin. In addition, with the bacteriostatic ratio and the overall desirability of the contents of four active components as indexes, the orthogonal experiment was adopted to detect the effect of water addition, extraction frequency and extraction time. The optimal extraction process was to add 12 times of water for the first time, 10 times of water for the second time, extract for 2 time, 2 h for each time. This optimization process is stable and feasible, with a higher bacteriostatic ratio in extracts.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fracionamento Químico/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Scutellaria baicalensis/química , Álcoois/química , Antibacterianos/química , Medicamentos de Ervas Chinesas/química , Água/química
7.
Zhongguo Zhong Yao Za Zhi ; 34(7): 833-5, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19623974

RESUMO

OBJECTIVE: To determine the contents of total saponin in the unprocessed Semen Platycladi and defatted powder of Semen Platycladi. METHOD: Through contrasting different coloration, proper condition was selected by using orthogonal test design. Spectrophotometry was established to determine the contents of total saponin in the unprocessed Semen Platycladi and defatted powder of Semen Platycladi. RESULT: Coloration system of vanillin-acetic acid-sulfuric acid was determined. The proper condition of coloration was that sulfuric acid was 80%, water bathed 85 and heated for 10 minutes. The contents of total saponin in unprocessed Semen Platycladi was 0.142% the content of total saponin in the defatted powder of Semen Platycladi was 0. 319%. CONCLUSION: This method, stable, simple and quick, is applicable to the determination of total saponin in Semen Platycladi. A Little of total saponin is lost in the processing course of Semen Platycladi.


Assuntos
Cupressaceae/química , Ácidos Graxos/isolamento & purificação , Saponinas/análise , Ácidos Graxos/química , Pós , Sensibilidade e Especificidade , Temperatura , Fatores de Tempo
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