501 research outputs found
Cytotoxic Potential of Rare Plant Salvia candidissima subsp. candidissima on Breast Cancer Cells
© 2023 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC), https://creativecommons.org/licenses/by-nc/4.0/Breast cancer is the leading cause of cancer-related deaths in women throughout the world. Research on natural anti-cancer products from plants has gained traction. Salvia L. species and their derivatives are rare in Turkey and have suggested for their potential anti-cancer effects. The aim of this study is to assess the potential cytotoxic/apoptotic activities of methanol extract of Salvia candidissima Vahl. subsp. candidissima (SCE) on MCF-7 and MDA-MB-231 breast cancer cells. A GCxGC-TOF/MS system and a dual stage commercial thermal desorption injector were used to determine the chemical components of SCE. MTT and ATP viability tests were used to investigate the anti-growth activity. The apoptosis-inducing effect was assessed using a fluorescence staining method. Caspase-cleaved keratin 18 (ccK18, M30-antigen) levels measured by M30-CytoDeath ELISA Kit. The results showed that SCE suppressed the survival of the MCF-7 and MDA-MB-231 breast cancer cells in a dose-dependent manner, based on the findings of both MTT and ATP cell viability tests and pyknotic cell nuclei were observed via fluorescent staining in both cell lines after 48 h of treatment. The treatment group had greater levels of caspase-cleaved keratin 18 in the MCF-7 cells than the untreated group. These results showed that SCE triggers apoptosis, causes cell death in MCF-7 and MDA-MB-231 cell lines. SCE may become promising therapeutic strategy in the treatment of breast cancer with further in vitro and in vivo studies.Peer reviewe
Phase diagram of neutron-rich nuclear matter and its impact on astrophysics
Dense matter as it can be found in core-collapse supernovae and neutron stars
is expected to exhibit different phase transitions which impact the matter
composition and equation of state, with important consequences on the dynamics
of core-collapse supernova explosion and on the structure of neutron stars. In
this paper we will address the specific phenomenology of two of such
transitions, namely the crust-core solid-liquid transition at sub-saturation
density, and the possible strange transition at super-saturation density in the
presence of hyperonic degrees of freedom. Concerning the neutron star
crust-core phase transition at zero and finite temperature, it will be shown
that, as a consequence of the presence of long-range Coulomb interactions, the
equivalence of statistical ensembles is violated and a clusterized phase is
expected which is not accessible in the grand-canonical ensemble. A specific
quasi-particle model will be introduced to illustrate this anomalous
thermodynamics and some quantitative results relevant for the supernova
dynamics will be shown. The opening of hyperonic degrees of freedom at higher
densities corresponding to the neutron stars core modifies the equation of
state. The general characteristics and order of phase transitions in this
regime will be analyzed in the framework of a self-consistent mean-field
approach.Comment: Invited Talk given at the 11th International Conference on
Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1,
2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference
Series (JPCS
Precise Localization of the Soft Gamma Repeater SGR 1627-41 and the Anomalous X-ray Pulsar AXP 1E1841-045 with Chandra
We present precise localizations of AXP 1E1841-045 and SGR 1627-41 with
Chandra. We obtained new infrared observations of SGR 1627-41 and reanalyzed
archival observations of AXP 1E1841-045 in order to refine their positions and
search for infrared counterparts. A faint source is detected inside the error
circle of AXP 1E1841-045. In the case of SGR 1627-41, several sources are
located within the error radius of the X-ray position and we discuss the
likelihood of one of them being the counterpart. We compare the properties of
our candidates to those of other known AXP and SGR counterparts. We find that
the counterpart candidates for SGR 1627-41 and SGR 1806-20 would have to be
intrinsically much brighter than AXPs to have detectable counterparts with the
observational limits currently available for these sources. To confirm the
reported counterpart of SGR 1806-20, we obtained new IR observations during the
July 2003 burst activation of the source. No brightening of the suggested
counterpart is detected, implying that the counterpart of SGR 1806-20 remains
yet to be identified.Comment: 29 pages, 4 figures, accepted for publication in Ap
Neutron rich matter, neutron stars, and their crusts
Neutron rich matter is at the heart of many fundamental questions in Nuclear
Physics and Astrophysics. What are the high density phases of QCD? Where did
the chemical elements come from? What is the structure of many compact and
energetic objects in the heavens, and what determines their electromagnetic,
neutrino, and gravitational-wave radiations? Moreover, neutron rich matter is
being studied with an extraordinary variety of new tools such as Facility for
Rare Isotope Beams (FRIB) and the Laser Interferometer Gravitational Wave
Observatory (LIGO). We describe the Lead Radius Experiment (PREX) that is using
parity violation to measure the neutron radius in 208Pb. This has important
implications for neutron stars and their crusts. Using large scale molecular
dynamics, we model the formation of solids in both white dwarfs and neutron
stars. We find neutron star crust to be the strongest material known, some 10
billion times stronger than steel. It can support mountains on rotating neutron
stars large enough to generate detectable gravitational waves. Finally, we
describe a new equation of state for supernova and neutron star merger
simulations based on the Virial expansion at low densities, and large scale
relativistic mean field calculations.Comment: 10 pages, 2 figures, Plenary talk International Nuclear Physics
Conference 2010, Vancouver, C
Stability window and mass-radius relation for magnetized strange quark stars
The stability of magnetized strange quark matter (MSQM) is investigated
within the phenomenological MIT bag model, taking into account the variation of
the relevant input parameters, namely, the strange quark mass, baryon density,
magnetic field and bag parameter. We obtain that the energy per baryon
decreases as the magnetic field increases, and its minimum value at vanishing
pressure is lower than the value found for SQM. This implies that MSQM is more
stable than non-magnetized SQM. Furthermore, the stability window of MSQM is
found to be wider than the corresponding one of SQM. The mass-radius relation
for magnetized strange quark stars is also derived in this framework.Comment: 12 pages, 6 figures, 3 table
The identification of the optical companion to the binary millisecond pulsar J0610-2100 in the Galactic field
We have used deep V and R images acquired at the ESO Very Large Telescope to
identify the optical companion to the binary pulsar PSR J0610-2100, one of the
black-widow millisecond pulsars recently detected by the Fermi Gamma-ray
Telescope in the Galactic plane. We found a faint star (V~26.7) nearly
coincident (\delta r ~0".28) with the pulsar nominal position. This star is
visible only in half of the available images, while it disappears in the
deepest ones (those acquired under the best seeing conditions), thus indicating
that it is variable. Although our observations do not sample the entire orbital
period (P=0.28 d) of the pulsar, we found that the optical modulation of the
variable star nicely correlates with the pulsar orbital period and describes a
well defined peak (R~25.6) at \Phi=0.75, suggesting a modulation due to the
pulsar heating. We tentatively conclude that the companion to PSR J0610-2100 is
a heavily ablated very low mass star (~ 0.02Msun) that completely filled its
Roche Lobe.Comment: 17 pages, 5 figures - Accepted for pubblication in Ap
The Dark Side of ROTSE-III Prompt GRB Observations
We present several cases of optical observations during gamma-ray bursts
(GRBs) which resulted in prompt limits but no detection of optical emission.
These limits constrain the prompt optical flux densities and the optical
brightness relative to the gamma-ray emission. The derived constraints fall
within the range of properties observed in GRBs with prompt optical detections,
though at the faint end of optical/gamma flux ratios. The presently accessible
prompt optical limits do not require a different set of intrinsic or
environmental GRB properties, relative to the events with prompt optical
detections.Comment: ApJ accepted. 20 pages in draft manuscript form, which includes 6
pages of tables and 2 figure
EGRET Gamma-Ray Observations of the Crab P2/P1 Ratio
Recent observations of the Crab pulsar by the Energetic Gamma-Ray Experiment
Telescope (EGRET) on the Compton Gamma Ray Observatory show that the
high-energy gamma-ray light curve has changed little over the lifetime of the
instrument. Previous data collected by SAS-2 and COS-B in the years 1972-82,
along with earlier EGRET data, suggested a 14 year sinusoidal variation in the
flux ratio between the first and second peaks. The new data from EGRET indicate
that the flux ratio is constant.Comment: 6 pages, 3 figures. To be published in Ap
Nutritional status in Turkish cystic fibrosis patients
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