6,752 research outputs found
Mitochondrial apoptosis induced by Chamaemelum nobile extract in breast cancer cells
Chamaemelum nobile (Asteraceae) commonly known as ‹Roman chamomile› is a medicinal plant used for numerous diseases in traditional medicine, although its anticancer activity is unknown. The present study was carried out to investigate the anticancer as well as apoptotic activity of ethyl acetate fraction of C. nobile on different cancerous cell lines. The cells were treated with varying concentrations (0.001-0.25 mg/mL) of this fraction for 24, 48 and 72 h. Apoptosis induced in MCF-7 cells following treatment with ethyl acetate fraction was measured using Annexin V/PI, flowcytometry and western blotting analysis. The results showed that C. nobile ethyl acetate fraction revealed relatively high antiproliferative activity on MCF-7 cells; however, it caused minimal growth inhibitory response in normal cells. The involvement of apoptosis as a major cause of the fraction-induced cell death was confirmed by annexin-V/PI assay. In addition, ethyl acetate fraction triggered the mitochondrial apoptotic pathway by decreasing the Bcl-2 as well as increasing of Bax protein expressions and subsequently increasing Bax/Bcl-2 ratio. Furthermore, decreased proliferation of MCF-7 cells in the presence of the fraction was associated with G2/M phase cell cycle arrest. These findings confirm that ethyl acetate fraction of C.nobile may contain a diversity of phytochemicals which suppress the proliferation of MCF-7 cells by inducing apoptosis. © 2016 by School of Pharmacy Shaheed Beheshti University of Medical Sciences and Health Services
From Causes for Database Queries to Repairs and Model-Based Diagnosis and Back
In this work we establish and investigate connections between causes for
query answers in databases, database repairs wrt. denial constraints, and
consistency-based diagnosis. The first two are relatively new research areas in
databases, and the third one is an established subject in knowledge
representation. We show how to obtain database repairs from causes, and the
other way around. Causality problems are formulated as diagnosis problems, and
the diagnoses provide causes and their responsibilities. The vast body of
research on database repairs can be applied to the newer problems of computing
actual causes for query answers and their responsibilities. These connections,
which are interesting per se, allow us, after a transition -inspired by
consistency-based diagnosis- to computational problems on hitting sets and
vertex covers in hypergraphs, to obtain several new algorithmic and complexity
results for database causality.Comment: To appear in Theory of Computing Systems. By invitation to special
issue with extended papers from ICDT 2015 (paper arXiv:1412.4311
Compute-and-Forward Can Buy Secrecy Cheap
We consider a Gaussian multiple access channel with transmitters, a
(intended) receiver and an external eavesdropper. The transmitters wish to
reliably communicate with the receiver while concealing their messages from the
eavesdropper. This scenario has been investigated in prior works using two
different coding techniques; the random i.i.d. Gaussian coding and the signal
alignment coding. Although, the latter offers promising results in a very high
SNR regime, extending these results to the finite SNR regime is a challenging
task. In this paper, we propose a new lattice alignment scheme based on the
compute-and-forward framework which works at any finite SNR. We show that our
achievable secure sum rate scales with and hence, in most
SNR regimes, our scheme outperforms the random coding scheme in which the
secure sum rate does not grow with power. Furthermore, we show that our result
matches the prior work in the infinite SNR regime. Additionally, we analyze our
result numerically.Comment: Accepted to ISIT 2015, 5 pages, 3 figure
- …