226 research outputs found
Targeting kinases with anilinopyrimidines: Discovery of N-phenyl-N'-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives as selective inhibitors of class III receptor tyrosine kinase subfamily
Kinase inhibitors are attractive drugs/drug candidates for the treatment of cancer. The most recent
literature has highlighted the importance of multi target kinase inhibitors, although a correct
balance between specificity and non-specificity is required. In this view, the discovery of multityrosine
kinase inhibitors with subfamily selectivity is a challenging goal. Herein we present the
synthesis and the preliminary kinase profiling of a set of novel 4-anilinopyrimidines. Among the
synthesized compounds, the N-phenyl-N\u2019-[4-(pyrimidin-4-ylamino)phenyl]urea derivatives selectively
targeted some members of class III receptor tyrosine kinase family. Starting from the structure of
hit compound 19 we synthesized a further compound with an improved affinity toward the class III
receptor tyrosine kinase members and endowed with a promising antitumor activity both in vitro
and in vivo in a murine solid tumor model. Molecular modeling simulations were used in order to
rationalize the behavior of the title compounds
The Next Generation Virgo Cluster Survey XVI. The Angular Momentum of Dwarf Early-Type Galaxies from Globular Cluster Satellites
We analyze the kinematics of six Virgo cluster dwarf early-type galaxies
(dEs) from their globular cluster (GC) systems. We present new Keck/DEIMOS
spectroscopy for three of them and reanalyze the data found in the literature
for the remaining three. We use two independent methods to estimate the
rotation amplitude (Vmax) and velocity dispersion (sigma_GC) of the GC systems
and evaluate their statistical significance by simulating non-rotating GC
systems with the same number of GC satellites and velocity uncertainties. Our
measured kinematics agree with the published values for the three galaxies from
the literature and, in all cases, some rotation is measured. However, our
simulations show that the null hypothesis of being non-rotating GC systems
cannot be ruled out. In the case of VCC1861, the measured Vmax and the
simulations indicate that it is not rotating. In the case of VCC1528, the null
hypothesis can be marginally ruled out, thus, it might be rotating although
further confirmation is needed. In our analysis, we find that, in general, the
measured Vmax tends to be overestimated and the measured sigma_GC tends to be
underestimated by amounts that depend on the intrinsic Vmax/sigma_GC, the
number of observed GCs (N_GC), and the velocity uncertainties. The bias is
negligible when N_GC>~20. In those cases where a large N_GC is not available,
it is imperative to obtain data with small velocity uncertainties. For
instance, errors of <2km/s lead to Vmax<10km/s for a system that is
intrinsically not rotating.Comment: ApJ in press. 20 pages, 17 figures, 5 table
The GALEX Ultraviolet Virgo Cluster Survey (GUViCS) III. The Ultraviolet Source Catalogs
In this paper we introduce the deepest and most extensive ultraviolet
extragalactic source catalogs of the Virgo Cluster area to date. Archival and
targeted GALEX imaging is compiled and combined to provide the deepest possible
coverage over ~120 deg^2 in the NUV (lambda_eff=2316 angstroms) and ~40 deg^2
in the FUV (lambda_eff=1539 angstroms) between 180 deg <= R.A. <= 195 deg and 0
deg <= Decl. <= 20 deg. We measure the integrated photometry of 1770 extended
UV sources of all galaxy types and use GALEX pipeline photometry for 1,230,855
point-like sources in the foreground, within, and behind the cluster. Extended
source magnitudes are reliable to m_UV ~22, showing ~0.01 sigma difference from
their asymptotic magnitudes. Point-like source magnitudes have a 1 sigma
standard deviation within ~0.2 mag down to m_uv ~23. The point-like source
catalog is cross-matched with large optical databases and surveys including the
SDSS DR9 (> 1 million Virgo Cluster sources), the Next Generation Virgo Cluster
Survey (NGVS; >13 million Virgo Cluster sources), and the NED (~30,000 sources
in the Virgo Cluster). We find 69% of the entire UV point-like source catalog
has a unique optical counterpart, 11% of which are stars and 129 are Virgo
cluster members neither in the VCC nor part of the bright CGCG galaxy catalog
(i.e., m_pg < 14.5). These data are collected in four catalogs containing the
UV extended sources, the UV point-like sources, and two catalogs each
containing the most relevant optical parameters of UV-optically matched
point-like sources for further studies from SDSS and NGVS. The GUViCS catalogs
provide a unique set of data for future works on UV and multiwavelength studies
in the cluster and background environments.Comment: 35 pages, 24 figures, 15 tables, Accepted for publication in A&
Transabdominal pre-peritoneal mesh in inguinal hernia repair in elderly: end point of our experience
BACKGROUND: Aim of this study is to present our standardized laparoscopic transabdominal preperitoneal hernia repair (TAPP) technique, and to study our experience in the elderly as far as concerns preoperative and postoperative variables. METHODS: We described our standardized TAPP technique according with Stuttgart technique [1], and we evalutated our team's experience in TAPP inguinal hernia repair in elderly (> 65 yrs) and in young patients (< 65 yrs). RESULTS: We retrospectively reviewed our Surgery Division's experience about TAPP; we included in our study 185 patients. The sample was subdivided in two groups: TAPP Group (< 65 years patients) and TAPPe Group (> 65 years patients). TAPP Group was composed by 154 patients and TAPPe Group of 31 patients. According with literature, in this subgroup recurrence rate (3,2%), early and delayed complications and mean operative time (86 min). There were no major vascular or intestinal complications. At the moment follow-up is 31 months. There were no incisional hernias on umbilical trocar. Mean satisfaction rate was excellent also in elderly patients. CONCLUSIONS: According with literature, in our experience TAPP technique is a safe and feasible procedure, even in elderly patients
Selection bias in dynamically measured supermassive black hole samples : its consequences and the quest for the most fundamental relation
We compare the set of local galaxies having dynamically measured black holes with a large, unbiased sample of galaxies extracted from the Sloan Digital Sky Survey. We confirm earlier work showing that the majority of black hole hosts have significantly higher velocity dispersions sigma than local galaxies of similar stellar mass. We use Monte Carlo simulations to illustrate the effect on black hole scaling relations if this bias arises from the requirement that the black hole sphere of influence must be resolved to measure black hole masses with spatially resolved kinematics. We find that this selection effect artificially increases the normalization of the M-bh-sigma relation by a factor of at least similar to 3; the bias for the M-bh-M-star relation is even larger. Our Monte Carlo simulations and analysis of the residuals from scaling relations both indicate that sigma is more fundamental than M-star or effective radius. In particular, the M-bh-M-star relation is mostly a consequence of the M-bh-sigma and sigma-M-star relations, and is heavily biased by up to a factor of 50 at small masses. This helps resolve the discrepancy between dynamically based black hole-galaxy scaling relations versus those of active galaxies. Our simulations also disfavour broad distributions of black hole masses at fixed sigma. Correcting for this bias suggests that the calibration factor used to estimate black hole masses in active galaxies should be reduced to values of f(vir) similar to 1. Black hole mass densities should also be proportionally smaller, perhaps implying significantly higher radiative efficiencies/black hole spins. Reducing black hole masses also reduces the gravitational wave signal expected from black hole mergers.Peer reviewe
The Next Generation Virgo Cluster Survey. X. Properties of Ultra-Compact Dwarfs in the M87, M49 and M60 Regions
We use imaging from the Next Generation Virgo cluster Survey (NGVS) to
present a comparative study of ultra-compact dwarf (UCD) galaxies associated
with three prominent Virgo sub-clusters: those centered on the massive,
red-sequence galaxies M87, M49 and M60. We show how UCDs can be selected with
high completeness using a combination of half-light radius and location in
color-color diagrams ( or ). Although the central galaxies in
each of these sub-clusters have nearly identical luminosities and stellar
masses, we find large differences in the sizes of their UCD populations, with
M87 containing ~3.5 and 7.8 times more UCDs than M49 and M60, respectively. The
relative abundance of UCDs in the three regions scales in proportion to
sub-cluster mass, as traced by X-ray gas mass, total gravitating mass, number
of globular clusters, and number of nearby galaxies. We find that the UCDs are
predominantly blue in color, with ~85% of the UCDs having colors similar to
blue GCs and stellar nuclei of dwarf galaxies. We present evidence that UCDs
surrounding M87 and M49 may follow a morphological sequence ordered by the
prominence of their outer, low surface brightness envelope, ultimately merging
with the sequence of nucleated low-mass galaxies, and that envelope prominence
correlates with distance from either galaxy. Our analysis provides evidence
that tidal stripping of nucleated galaxies is an important process in the
formation of UCDs.Comment: 37 pages, 40 figures. To appear in The Astrophysical Journa
The Next Generation Virgo Cluster Survey. VIII. The Spatial Distribution of Globular Clusters in the Virgo Cluster
We report on a large-scale study of the distribution of globular clusters
(GCs) throughout the Virgo cluster, based on photometry from the Next
Generation Virgo Cluster Survey, a large imaging survey covering Virgo's
primary subclusters to their virial radii. Using the g', (g'-i')
color-magnitude diagram of unresolved and marginally-resolved sources, we
constructed 2-D maps of the GC distribution. We present the clearest evidence
to date showing the difference in concentration between red and blue GCs over
the extent of the cluster, where the red (metal-rich) GCs are largely located
around the massive early-type galaxies, whilst the blue (metal-poor) GCs have a
more extended spatial distribution, with significant populations present beyond
83' (215 kpc) along the major axes of M49 and M87. The GC distribution around
M87 and M49 shows remarkable agreement with the shape, ellipticity and boxiness
of the diffuse light surrounding both galaxies. We find evidence for spatial
enhancements of GCs surrounding M87 that may be indicative of recent
interactions or an ongoing merger history. We compare the GC map to the
locations of Virgo galaxies and the intracluster X-ray gas, and find good
agreement between these baryonic structures. The Virgo cluster contains a total
population of 6730014400 GCs, of which 35% are located in M87 and M49
alone. We compute a cluster-wide specific frequency S_N,CL=,
including Virgo's diffuse light. The GC-to-baryonic mass fraction is
e_b=and the GC-to-total cluster mass formation
efficiency is e_t=, values slightly lower than, but
consistent with, those derived for individual galactic halos. Our results show
that the production of the complex structures in the unrelaxed Virgo cluster
core (including the diffuse intracluster light) is an ongoing
process.(abridged)Comment: 23 pages, 17 figures. Accepted for publication in the Astrophysical
Journal. Figure 1 has reduced resolution. Revised version with updated
references, corrected typos -- no changes to result
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