2,346 research outputs found
Doxorubicin resistant choriocarcinoma cell line derived spheroidal cells exhibit stem cell markers but reduced invasion
Cell cycle-specifc cancer chemotherapy is based on the ability of a drug to halt, minimise or destroy rapidly dividing cells. However, their efcacy is limited by the emergence of a self-renewing cell pool called “cancer stem cells” (CSC). Choriocarcinoma is a tumour of trophoblastic tissue. We, in this study, analysed whether spheroids generated from doxorubicintreated and non-treated choriocarcinoma cell lines exhibit markers of stem cells. Two choriocarcinoma cell lines, namely JEG-3 and BeWo, were used in this study. Spheroids were generated from doxorubicin-treated cells and the non-treated cells under non-adherent condition, followed by analysis of stem-cell markers’ expression, namely NANOG, OCT4 and SOX2. Immunofuorescence analysis suggested a general increase in the markers’ concentration in spheroids relative to the parental cells. RT-qPCR and immunoblots showed an increase in the stem-cell marker expression in spheroids generated from doxorubicin-treated when compared to non-treated cells. In spheroids, Sox2 was signifcantly upregulated in doxorubicintreated spheroids, whereas Nanog and Oct4 were generally downregulated when compared to non-treated spheroids. Both
2D and 3D invasion assays showed that the spheroids treated with doxorubicin exhibited reduced invasion. Our data suggest
that choriocarcinoma cell lines may have the potential to produce spheroidal cells, yet the drug-treatment afected the invasion potential of spheroids
A Generative-Discriminative Basis Learning Framework to Predict Clinical Severity from Resting State Functional MRI Data
We propose a matrix factorization technique that decomposes the resting state
fMRI (rs-fMRI) correlation matrices for a patient population into a sparse set
of representative subnetworks, as modeled by rank one outer products. The
subnetworks are combined using patient specific non-negative coefficients;
these coefficients are also used to model, and subsequently predict the
clinical severity of a given patient via a linear regression. Our
generative-discriminative framework is able to exploit the structure of rs-fMRI
correlation matrices to capture group level effects, while simultaneously
accounting for patient variability. We employ ten fold cross validation to
demonstrate the predictive power of our model on a cohort of fifty eight
patients diagnosed with Autism Spectrum Disorder. Our method outperforms
classical semi-supervised frameworks, which perform dimensionality reduction on
the correlation features followed by non-linear regression to predict the
clinical scores
Near-IR studies of recurrent nova V745 Scorpii during its 2014 outburst
The recurrent nova (RN) V745 Scorpii underwent its third known outburst on
2014 February 6. Infrared monitoring of the eruption on an almost daily basis,
starting from 1.3d after discovery, shows the emergence of a powerful blast
wave generated by the high velocity nova ejecta exceeding 4000 kms
plowing into its surrounding environment. The temperature of the shocked gas is
raised to a high value exceeding 10K immediately after outburst
commencement. The energetics of the outburst clearly surpass those of similar
symbiotic systems like RS Oph and V407 Cyg which have giant secondaries. The
shock does not show a free-expansion stage but rather shows a decelerative
Sedov-Taylor phase from the beginning. Such strong shockfronts are known to be
sites for ray generation. V745 Sco is the latest nova, apart from five
other known novae, to show ray emission. It may be an important
testbed to resolve the crucial question whether all novae are generically
ray emitters by virtue of having a circumbinary reservoir of material
that is shocked by the ejecta rather than ray generation being
restricted to only symbiotic systems with a shocked red giant (RG) wind. The
lack of a free-expansion stage favors V745 Sco to have a density enhancement
around the white dwarf (WD), above that contributed by a RG wind. Our analysis
also suggests that the WD in V745 Sco is very massive and a potential
progenitor for a future SN Ia explosion.Comment: To appear in ApJ (Letters
Doping dependence of charge-transfer excitations in La_{2-x}Sr_xCuO_4
We report a resonant inelastic x-ray scattering (RIXS) study of the doping
dependence of charge-transfer excitations in . The mome
ntum dependence of these charge excitations are studied over the whole
Brillouin zone in underdoped (x=0.05) and optimally doped (x=0.17) samples, and
compared with that of the undoped (x=0) sample. We observe a large change in
the RIXS spectra between the x=0 and x=0.17 sample, while the RIXS spectra of
the x=0.05 sample are similar to that of the x=0 sample. The most prominent
effect of doped-holes on the charge excitation spectra is the appearance of a
continuum of intensity, which exhibits a strong momentum-dependence below 2 eV.
For the x=0.17 sample, some of the spectral weight from the lowest-lying
charge-transfer excitation of the undoped compound is transferred to the
continuum intensity below the gap, in agreement with earlier optical studies.
However, the higher energy charge-transfer excitation carries significant
spectral weight even for the x=0.17 sample. The doping dependence of the
dispersion of this charge-transfer excitation is also discussed and compared
with recent theoretical calculations.Comment: 7 pages, 6 figures, to appear in Phys. Rev.
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