PubMed İndeksli Yayınlar / PubMed Indexed Publications

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Browsing PubMed İndeksli Yayınlar / PubMed Indexed Publications by Subject "Activation"

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    Emotional Face Expressions are Differentiated With Brain Oscillations
    (ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Güntekin, Bahar; BAŞAR, EROL; TR204666; TR142226
    The differentiation of "facial expressions" is a process of higher mental activity, which has considerable applications in "psychology of moods and emotions". We applied the approach of event-related oscillations (EROs) to investigate the modulation of electrical manifestations related to emotional expression in EEG recordings of 20 healthy subjects. EROs of "neutral, angry and happy" faces in 13 electrical recordings sites (F-3, F-4, C-z, C-3, C-4, T-3, T-4, T-5, T-6, P-3, P-4, O-1, O-2) were analyzed. Following the recording session, the subjects were asked to express the degree of their emotional involvement (valence and arousal) using the Self-Assessment Manikin ratings. Amplitude frequency characteristics (AFCs) were used to determine the frequencies of interest and the ranges for digital pass-band filtering applied accordingly. Consecutively, peak to peak amplitude measures of oscillatory responses were computed for the selected frequency bands and for the differentiation of the different stimuli. A differentiation between angry and happy facial expressions was observed especially in the alpha (9-13 Hz) and beta (15-24 Hz) frequencies, however, only when selecting stimuli with high mood involvement. Therefore, these frequency bands are the main focus of this report. The amplitudes of the alpha responses upon angry face stimulation were significantly higher than upon presentation of the happy faces at posterior locations. At F3, C, and C3, beta responses upon angry face stimulation were significantly higher in amplitude compared with the happy face stimulation. It is discussed that the frontal theta response is highly increased in comparison to all theta responses also encountered in studies of face recognition: During observation of facial expression, the occipital theta is much higher. We conclude and emphasize that the analysis of brain oscillatory responses distributed over the scalp in combination with subjective ratings of emotional impact of stimuli provide a good basis for analysing the influence of emotional information processing in the brain. In congruence with others, the results support the phylogenetical viewpoint suggesting that angry face stimulations are faster and more ample in responding. Furthermore, frontal, temporal, parietal and occipital lobes seem to be involved in processing of facial expressions, as reflected in an ensemble of different frequency brain oscillatory responses distributed over the scalp. (c) 2006 Published by Elsevier B.V.
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    The inhibition of PI3K and NF kappa B promoted curcumin-induced cell cycle arrest at G2/M via altering polyamine metabolism in Bcl-2 overexpressing MCF-7 breast cancer cells
    (Elsevier France-Editions Scientifiques Medicales Elsevier, 23 Rue Linois, 75724 Paris, France, 2016-02) Akkoç, Yunus; Çoker Gürkan, Ajda; Palavan Ünsal, Zeynep Narçın; Berrak, Özge; ARISAN, ELİF DAMLA; YERLİKAYA, PINAR OBAKAN; 113920; 125860; 156421; 6125
    Bcl-2 protein has been contributed with number of genes which are involved in oncogenesis. Among the many targets of Bcl-2, NF kappa B have potential role in induction of cell cycle arrest. Curcumin has potential therapeutic effects against breast cancer through multiple signaling pathways. In this study, we investigated the role of curcumin in induction of cell cycle arrest via regulating of NF kappa B and polyamine biosynthesis in wt and Bcl-2+ MCF-7 cells. To examine the effect of curcumin on cell cycle regulatory proteins, PI3K/Akt, NF kappa B pathways and polyamine catabolism, we performed immunoblotting assay. In addition, cell cycle analysis was performed by flow cytometry. The results indicated that curcumin induced cell cycle arrest at G2/M phase by downregulation of cyclin B1 and Cdc2 and inhibited colony formation in MCF-7 wt cells. However, Bcl-2 overexpression prevented the inhibition of cell cycle associated proteins after curcumin treatment. The combination of LY294002, PI3K inhibitor, and curcumin induced cell cycle arrest by decreasing CDK4, CDK2 and cyclin E2 in Bcl-2+ MCF-7 cells. Moreover, LY294002 further inhibited the phosphorylation of Akt in Bcl-2+ MCF-7 cells. Curcumin could suppress the nuclear transport of NF kappa B through decreasing the interaction of P-I kappa B-NF kappa B. The combination of wedelolactone, NF kappa B inhibitor, and curcumin acted different on SSAT expression in wt MCF-7 and Bcl-2+ MCF-7 cells. NF kappa B inhibition increased the SSAT after curcumin treatment in Bcl2 overexpressed MCF-7 cells. Inhibition of NF kappa B activity as well as suppression of ROS generation with NAC resulted in the partial relief of cells from G2/M checkpoint after curcumin treatment in wt MCF7 cells. In conclusion, the potential role of curcumin in induction of cell cycle arrest is related with NF kappa B-regulated polyamine biosynthesis. (C) 2015 Elsevier Masson SAS. All rights reserved.