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1.
Sensors (Basel) ; 15(4): 7323-48, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25815450

RESUMEN

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes--the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC--were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes.

2.
Artículo en Inglés | MEDLINE | ID: mdl-22046195

RESUMEN

HDAC inhibitors (HDACis) have been developed as promising anticancer agents in recent years. In this study, we synthesized and characterized a novel HDACi, termed NBM-HD-1. This agent was derived from the semisynthesis of propolin G, isolated from Taiwanese green propolis (TGP), and was shown to be a potent suppressor of tumor cell growth in human breast cancer cells (MCF-7 and MDA-MB-231) and rat glioma cells (C6), with an IC(50) ranging from 8.5 to 10.3 µM. Western blot demonstrated that levels of p21((Waf1/Cip1)), gelsolin, Ac-histone 4, and Ac-tubulin markedly increased after treatment of cancer cells with NBM-HD-1. After NBM-HD-1 treatment for 1-4 h, p-PTEN and p-AKT levels were markedly decreased. Furthermore, we also found the anticancer activities of NBM-HD-1 in regulating cell cycle regulators. Treatment with NBM-HD-1, p21((Waf1/Cip1)) gene expression had markedly increased while cyclin B1 and D1 gene expressions had markedly decreased. On the other hand, we found that NBM-HD-1 increased the expressions of tumor-suppressor gene p53 in a dose-dependent manner. Finally, we showed that NBM-HD-1 exhibited potent antitumor activity in a xenograft model. In conclusion, this study demonstrated that this compound, NBM-HD-1, is a novel and potent HDACi with anticancer activity in vitro and in vivo.

3.
Cancer Lett ; 291(1): 108-19, 2010 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19913353

RESUMEN

Liverwort constituents have been reported to exert a broad spectrum of biological activities. In this study, we used a bioactivity-guided separation of an extract from the liverwort species Marchantia emarginata subsp. tosana to determine its anticancer activity. A high level of the active ingredient was isolated from this liverwort and its chemical structure was identified and characterized by various spectra. It was found to be identical to a well-known compound, marchantin A, a cyclic bisbibenzyl ether. However, no anticancer activities of this compound have previously been reported. We found that marchantin A efficiently induced cell growth inhibition in human MCF-7 breast cancer cells, with an IC(50) of 4.0microg/mL. Fluorescence microscopy and a Western blot analysis indicated that marchantin A actively induced apoptosis of MCF-7 cells. The levels of cleaved caspase-8, cleaved caspase-3, cleaved caspase-9, and cleaved poly (ADP ribose) polymerase (PARP) increased. However, the level of Bid markedly decreased in a dose- and time-dependent manner. We also evaluated the anticancer activities of marchantin A on the regulation of cell cycle regulators such as p21, p27, cyclin B1, and cyclin D1. The p21 and p27 gene expressions increased markedly while cyclin B1 and D1 gene expression decreased markedly by treatment with marchantin A. Many report demonstrated that liverwort was suggested to possess potent antioxidant activity. Our results indicate that marchantin A possesses free radical-scavenging activity (EC(50)=20microg/mL). Taken together, for the first time, the compound marchantin A from liverworts demonstrated to be a potent inducer of apoptosis in MCF-7 cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Bibencilos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Éteres Cíclicos/farmacología , Bibencilos/aislamiento & purificación , Neoplasias de la Mama/patología , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclina D1/genética , Éteres Cíclicos/aislamiento & purificación , Femenino , Depuradores de Radicales Libres/farmacología , Humanos
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