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1.
J Sep Sci ; 41(19): 3686-3696, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30059192

RESUMO

Multi-component analysis is one of the key techniques for the overall quality control of traditional Chinese medicines. However, the shortage and high cost of reference substances are the greatest obstacles. The substitute method is an alternative solution. In the present study, 11 compounds of rhubarb were simultaneously determined by a method named "two reference substances for determination of multiple components", which includes a qualitative method with linear calibration using two reference substances and a quantitative method with a relative correction factor combined with ultra high performance liquid chromatography. Using aloe-emodin-8-O-ß-D-glucopyranoside and chrysophanol as reference compounds, chromatographic peak identification was performed. The results demonstrated that linear calibration using two reference substances method showed higher accuracy, less deviation, and better column adaptability compared to the relative retention time method. Using chrysophanol as a reference compound, the relative correction factors were determined and showed good reproducibility and stability in different laboratories with different instruments, columns, and wavelength fluctuations. The results had no significant difference compared with the external standard method. The strategy of two reference substances for determination of multiple components coupled with ultra high performance liquid chromatography is economical, efficient, accurate, reliable, and environmentally friendly and is suitable for the quality control of traditional Chinese medicines.


Assuntos
Antraquinonas/química , Glucosídeos/química , Rheum/química , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa , Estrutura Molecular
2.
Langmuir ; 31(7): 2127-35, 2015 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-25635508

RESUMO

Through the use of a sacrificial carbon layer, this work reports a method of performing electrophoretic deposition (EPD) of thick films on fully nonconducting substrates, overcoming the restricting requirement for EPD of a conducting or partially conducting substrate. As a proof of concept, the method was applied to the development of microwave-thick films on insulating alumina substrates. The key parameter to be controlled is the thickness of the sacrificial carbon layer; this is expected to be a general result for the application of the processing method. The method allows direct patterning of the structure and leads to the potential use of EPD in a far wider range of electronic applications (multilayer ceramic capacitors (MLCCs), low-temperature cofired ceramics (LTTCs), and biotech devices). Furthermore, in conjunction with work reported elsewhere, the development of specific BaNd2Ti5O14 (BNT) thick-film microwave dielectrics opens up a technology platform for a range of high-quality factor (Q) devices. More specifically, 100-µm-thick BNT layers were achieved with a dielectric constant of 149 and Q of 1161 (10 GHz). These materials can now be integrated with tunable dielectrics or dielectrics on metal substrates to provide a platform for devices in the front end of communication systems and cellular base stations.

3.
Langmuir ; 28(5): 2944-9, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22206407

RESUMO

Nanoporous barium titanate and lead titanate thin films (∼100 nm calculated from ellipsometric data) are prepared starting from sol-gel solutions modified with a commercially available block-copolymer and evaporation-induced self-assembly methodology. The tuning of the thermal treatment followed by in situ ellipsometry allows the decomposition of the organic components and of the structuring agent leading to the formation of porous tetragonal crystalline perovskite structures as observed by XRD, HRTEM, SEM, and ellipsoporosimetry. Both nanoporous barium titanate and lead titanate thin films present local piezoelectric and ferroelectric behavior measured by piezoresponse force microscopy (PFM), being promising platforms for the preparation of the generation of new multifunctional systems.

4.
Artif Cells Nanomed Biotechnol ; 47(1): 2670-2677, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31257923

RESUMO

Wilms' tumour (WT) is a frequent primary malignant tumour of urinary system in children. LncRNAs small nucleolar RNA host gene 6 (SNHG6) modulates kinds of biological procedures of cancer cells. Our research is to explore the effect and associated regulatory mechanism of SNHG6 in WT. CCK8 assays and bromodeoxyuridine were used to determine cell viability and cell proliferation, respectively. Flow cytometric analysis was performed to measure cell apoptosis rate. Cell mobility was tested through transwell and migration assays. Western blotting was employed to test the expression of proteins related to cell proliferation, cell apoptosis and signal pathways. In the results, overexpression of SNHG6 was found in WT tissues. The knockdown of SNHG6 suppressed cell proliferation, migration and incursion, but promoted apoptosis. Further study found that the knockdown of SNHG6 elevated the expression of miR-15a. Then, the combination of miR-15a inhibitor abolished the inhibiting effect of si-SNHG6 on WT progression. We also found that the TAK1/JNK and Wnt/ß-catenin signal pathways were inactivated by the knockdown of SNHG6 through elevating the expression of miR-15a. In summary, SNHG6 is an oncogene of WT development by targeting miR-15a.


Assuntos
Movimento Celular/genética , Inativação Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Tumor de Wilms/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Invasividade Neoplásica/genética , RNA Longo não Codificante/metabolismo , Via de Sinalização Wnt/genética
5.
Zhongguo Zhong Yao Za Zhi ; 32(19): 2018-21, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18161295

RESUMO

OBJECTIVE: To develop a LC-MS-MS method for determination of adenosine and cordycepin in Cordyceps sinensis and it's substitutes. METHOD: The sawple was extracted with. 90% methanol. Multi-reactions monitoring (MRM) technique was adopted. RESULT: The regression equations and coefficients were Y = 89.04X + 506.85 (r = 0.999 7) for adenosine, Y = 99.66X + 1 251.34 (r = 0.998 8) for cordycepin respectively. The linear range was 5.0-1 000.0 microg x L(-1) for adenosine and cordycepin. The limits of detection (LOD) were 0. 44 microg x L(-1) for adenosine and 0.31 microg x L(-1) for cordycepin, respectively. The average recoveries of adenosine and cordycepin were 98.1% and 97.9%, respectively. CONCLUSION: The method was highly sensitive, selective and fast, which can be used for the determination of adenosine and cordycepin in C. sinensis and it's substitutes. This method can also be applied for the quality control of the medicinal materials.


Assuntos
Adenosina/análise , Cromatografia Líquida de Alta Pressão/métodos , Cordyceps/química , Desoxiadenosinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Adenosina/normas , Animais , Cordyceps/classificação , Desoxiadenosinas/normas , Controle de Qualidade , Valores de Referência , Reprodutibilidade dos Testes
6.
J Pharm Anal ; 7(5): 271-279, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29404049

RESUMO

An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines (TCMs). However, the current quality standard research lacks the top-design and systematic design, mostly based on specific technologies or evaluation methods. To resolve the challenges and questions of quality control of TCMs, a brand-new quality standard system, named "iVarious", was proposed. The system comprises eight elements in a modular format. Meaning of every element was specifically illustrated via corresponding research instances. Furthermore, frankincense study was taken as an example for demonstrating standards and research process, based on the "iVarious" system. This system highlighted a holistic strategy for effectiveness, security, integrity and systematization of quality and safety control standards of TCMs. The establishment of "iVarious" integrates multi-disciplinary technologies and progressive methods, basis elements and key points of standard construction. The system provides a novel idea and technological demonstration for regulation establishment of TCMs quality standards.

7.
Adv Mater ; 26(9): 1405-9, 2014 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-24339131

RESUMO

Functional ferroelectric oxides for flexible electronics are achieved from activated solutions enabling low-temperature processing and large-area deposition directly on polymeric substrates. This processing technology reaches the lower limit temperature of crystallization at 300 °C, using a strategy that combines seeded diphasic precursors and photochemical solution deposition. Properties of these materials are comparable to those of high-temperature-processed counterparts and organic ferroelectrics.

8.
J Phys Chem B ; 117(6): 1670-9, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23130647

RESUMO

The importance of electrophoretic deposition (EPD) is well recognized for thick film technology, but unfortunately there is no universal suspension medium for the EPD of oxides. Thus, the selection of the medium, the stability of the suspensions, and the control of the particle potentials, critical for a good deposition, need to be established for each new material being processed by EPD. In this article, we investigate the key parameters, studying the electrochemistry of BaNd(2)Ti(5)O(14) (BNT) suspensions, and establish relationships between suspension media, EPD process conditions, microstructure of the deposits, and resulting electrical properties of the BNT films. Suspension stability of water, ethanol, acetic acid, and acetone-based media was analyzed in terms of zeta potential, particle size distribution, UV transmittance, and inductively coupled plasma spectrometry. The highest absolute zeta potential values determined for acetone with I(2) and acetic acid media are in good agreement with the high stability, small and narrow particle size distribution, and low UV light transmittance measured for these suspensions. Very high quality thick deposits were consequently achieved. However, it was demonstrated that aging of the acetic acid-based suspension have serious negative effects on the EPD process for BNT materials, including leaching of the metallic elements with a consequent modification of the material stoichiometry, change of the conductivity of the suspension, and degradation of the films microstructure. These facts severely restrict the use of acetic acid. Our results clearly indicate that, besides the stability of the suspension, the electrochemistry and aging behavior are key aspects for the EPD of functional oxides. Our systematic approach could be viewed as providing a set of guidelines for the development of EPD of other oxides.

9.
Artigo em Chinês | WPRIM | ID: wpr-660723

RESUMO

An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines (TCMs). However, the current quality standard research lacks top-level design and systematic design, mostly based on specific technologies or evaluation methods. To resolve the challenges and questions of quality control of TCMs, a brand-new quality standard system, named "iVarious", was proposed. The system comprises eight elements in a modular format. Meaning of every element was specifically illustrated via corresponding research instances. Furthermore, frankincense study was taken as an example for demonstrating standards and research process, based on the "iVarious" system. This system highlighted a holistic strategy for effectiveness, security, integrity and systematization of quality and safety control standards of TCMs. The establishment of "iVarious" integrates multi-disciplinary technologies and progressive methods, basis elements and key points of standard construction. The system provides a novel idea and technological demonstration for regulation establishment of TCMs quality standards.

10.
Artigo em Chinês | WPRIM | ID: wpr-658039

RESUMO

An effective quality control system is the key to ensuring the quality, safety and efficacy of traditional Chinese medicines (TCMs). However, the current quality standard research lacks top-level design and systematic design, mostly based on specific technologies or evaluation methods. To resolve the challenges and questions of quality control of TCMs, a brand-new quality standard system, named "iVarious", was proposed. The system comprises eight elements in a modular format. Meaning of every element was specifically illustrated via corresponding research instances. Furthermore, frankincense study was taken as an example for demonstrating standards and research process, based on the "iVarious" system. This system highlighted a holistic strategy for effectiveness, security, integrity and systematization of quality and safety control standards of TCMs. The establishment of "iVarious" integrates multi-disciplinary technologies and progressive methods, basis elements and key points of standard construction. The system provides a novel idea and technological demonstration for regulation establishment of TCMs quality standards.

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