41 research outputs found
Tratamiento con talidomida en estomatitis aftosa recurrente en una paciente pediátrica
El uso de talidomia es controvertido y especialmente en población pediátrica, si bien es cierto las publicaciones disponibles avalan su uso en determinadas condiciones en las que la presencia de aftas bucales comprometa la calidad de vida de los pacientes y éstas no hayan sido resueltas con los tratamientos habituales.
En nuestro caso nos encontramos ante una paciente pediátrica donde la estomatitis aftosa condicionaba incluso su correcta alimentación, por este motivo y tras realizar las pruebas oportunas para determinar las causas de las mismas se decide comenzar el tratamiento con talidomida. Los resultados fueron muy positivos en cuanto a reducción de episodios aftosos pero los efectos adversos observados en la paciente condicionaron la suspensión del tratamiento.
La implicación farmacéutica hizo posible una coordinación entre atención primaria y especializada, un asesoramiento tanto a personal sanitario como a la paciente y tutores legales, la adquisición del fármaco y la elaboración de una fórmula magistral adaptada a los cambios posológicos. Por otro lado el estrecho seguimiento de la paciente y de los efectos adversos hizo posible su suspensión en el momento en el que la relación beneficio/riesgo ya no era favorable.
Tratamiento con talidomida en estomatitis aftosa recurrente en una paciente pediátrica
El uso de talidomia es controvertido y especialmente en población pediátrica, si bien es cierto las publicaciones disponibles avalan su uso en determinadas condiciones en las que la presencia de aftas bucales comprometa la calidad de vida de los pacientes y éstas no hayan sido resueltas con los tratamientos habituales.
En nuestro caso nos encontramos ante una paciente pediátrica donde la estomatitis aftosa condicionaba incluso su correcta alimentación, por este motivo y tras realizar las pruebas oportunas para determinar las causas de las mismas se decide comenzar el tratamiento con talidomida. Los resultados fueron muy positivos en cuanto a reducción de episodios aftosos pero los efectos adversos observados en la paciente condicionaron la suspensión del tratamiento.
La implicación farmacéutica hizo posible una coordinación entre atención primaria y especializada, un asesoramiento tanto a personal sanitario como a la paciente y tutores legales, la adquisición del fármaco y la elaboración de una fórmula magistral adaptada a los cambios posológicos. Por otro lado el estrecho seguimiento de la paciente y de los efectos adversos hizo posible su suspensión en el momento en el que la relación beneficio/riesgo ya no era favorable.
The SAMI Galaxy Survey: Stellar population radial gradients in early-type galaxies
We study the internal radial gradients of the stellar populations in a sample
comprising 522 early-type galaxies (ETGs) from the SAMI (Sydney- AAO
Multi-object Integral field spectrograph) Galaxy Survey. We stack the spectra
of individual spaxels in radial bins, and derive basic stellar population
properties: total metallicity ([Z/H]), [Mg/Fe], [C/Fe] and age. The radial
gradient () and central value of the fits (evaluated at R/4) are
compared against a set of six possible drivers of the trends. We find that
velocity dispersion () - or, equivalently gravitational potential - is
the dominant driver of the chemical composition gradients. Surface mass density
is also correlated with the trends, especially with stellar age. The decrease
of [Mg/Fe] with increasing is contrasted by a rather shallow
dependence of [Z/H] with (although this radial gradient is
overall rather steep). This result, along with a shallow age slope at the
massive end, imposes stringent constraints on the progenitors of the
populations that contribute to the formation of the outer envelopes of ETGs.
The SAMI sample is split between a 'field' sample and a cluster sample. Only
weak environment-related differences are found, most notably a stronger
dependence of central total metallicity ([Z/H]) with , along
with a marginal trend of [Z/H] to steepen in cluster galaxies, a result
that is not followed by [Mg/Fe]. The results presented here serve as
constraints on numerical models of the formation and evolution of ETGs.Comment: 14 pages, 9 figures, 3 tables. Submitted to MNRA
Stellar populations of galaxies in the ALHAMBRA survey up to . II. Stellar content of quiescent galaxies within the dust-corrected stellar masscolour and the colourcolour diagrams
Our aim is to determine the distribution of stellar population parameters
(extinction, age, metallicity, and star formation rate) of quiescent galaxies
within the rest-frame stellar masscolour and colourcolour diagrams
corrected for extinction up to . These novel diagrams reduce the
contamination in samples of quiescent galaxies owing to dust-reddened galaxies,
and they provide useful constraints on stellar population parameters. We set
constraints on the stellar population parameters of quiescent galaxies
combining the ALHAMBRA multi-filter photo-spectra with our SED-fitting code
MUFFIT, making use of composite stellar population models. The extinction
obtained by MUFFIT allowed us to remove dusty star-forming (DSF) galaxies from
the sample of red galaxies. The distributions of stellar population
parameters across these rest-frame diagrams are revealed after the dust
correction and are fitted by the LOESS method to reduce uncertainty effects.
Quiescent galaxy samples defined via classical diagrams are typically
contaminated by a % fraction of DSF galaxies. A significant part of the
galaxies in the green valley are actually obscured star-forming galaxies
(%). Consequently, the transition of galaxies from the blue cloud to
the red sequence, and hence the related mechanisms for quenching, seems to be
much more efficient and faster than previously reported. The rest-frame stellar
masscolour and colourcolour diagrams are useful for constraining
the age, metallicity, extinction, and star formation rate of quiescent galaxies
by only their redshift, rest-frame colours, and/or stellar mass. Dust
correction plays an important role in understanding how quiescent galaxies are
distributed in these diagrams and is key to performing a pure selection of
quiescent galaxies via intrinsic colours.Comment: (37 pages, 29 figures, accepted for publication in A&A
Competitive Asymmetries in the Use of Supplementary Food by the Endangered Iberian Lynx (Lynx pardinus)
Background: As a conservation tool, supplementary feeding programs may be directed to specific individuals or sectors of the target population whose productivity or survival is thought to be limited by food scarcity. However, the use of supplemental food by different sex and age classes has received little attention. We studied individual variation in the access of the endangered Iberian lynx (Lynx pardinus) to supplementary food.
Methodology/Principal Findings: From 5349 pictures taken with automatic cameras placed in 25 feeding stations, we identified 28 individuals whose sex and age were known. All individuals known to live in areas subjected to supplementation regularly visited feeding stations. Food consumption was not proportional to expected variations in energy demand within sex and age classes. Food consumption by males was higher than by females, and increased with age, in agreement with a despotic distribution. Food consumption also increased with lynx body mass, and this pattern held for individuals sharing the same breeding territories. The access of inferior competitors increased with the number of feeding stations available within lynx territories.
Conclusions/Significance: All lynx exposed to food supplementation made a regular use of extra food but individuals predicted to be competitively dominant visited stations more frequently than subordinates of the same breeding territory. Our results suggest that insufficient provision of supplementary food could restrict the access of juveniles, or even adult females, to feeding stations. Limited consumption by these target individuals may compromise the efficiency of the supplementary feeding programme at the population level, in endangered species that, as the Iberian lynx, exhibit marked sexual dimorphism in body size.Peer reviewe
Anatomy of a post-starburst minor merger: a multi-wavelength WFC3 study of NGC 4150
(Abridged) We present a spatially-resolved near-UV/optical study of NGC 4150,
using the Wide Field Camera 3 (WFC3) on board the Hubble Space Telescope.
Previous studies of this early-type galaxy (ETG) indicate that it has a large
reservoir of molecular gas, exhibits a kinematically decoupled core (likely
indication of recent merging) and strong, central H_B absorption (indicative of
young stars). The core of NGC 4150 shows ubiquitous near-UV emission and
remarkable dusty substructure. Our analysis shows this galaxy to lie in the
near-UV green valley, and its pixel-by-pixel photometry exhibits a narrow range
of near-UV/optical colours that are similar to those of nearby E+A
(post-starburst) galaxies. We parametrise the properties of the recent star
formation (age, mass fraction, metallicity and internal dust content) in the
NGC 4150 pixels by comparing the observed near-UV/optical photometry to stellar
models. The typical age of the recent star formation (RSF) is around 0.9 Gyrs,
consistent with the similarity of the near-UV colours to post-starburst
systems, while the morphological structure of the young component supports the
proposed merger scenario. The RSF metallicity, representative of the
metallicity of the gas fuelling star formation, is around 0.3 - 0.5 Zsun.
Assuming that this galaxy is a merger and that the gas is sourced mainly from
the infalling companion, these metallicities plausibly indicate the gas-phase
metallicity (GPM) of the accreted satellite. Comparison to the local mass-GPM
relation suggests (crudely) that the mass of the accreted system is around
3x10^8 Msun, making NGC 4150 a 1:20 minor merger. A summation of the pixel RSF
mass fractions indicates that the RSF contributes about 2-3 percent of the
stellar mass. This work reaffirms our hypothesis that minor mergers play a
significant role in the evolution of ETGs at late epochs.Comment: 28 pages, 2 tables, accepted for publication in Ap
A Ks-band-selected catalogue of objects in the ALHAMBRA survey
The original ALHAMBRA catalogue contained over 400,000 galaxies selected using a synthetic F814W image, to the magnitude limit AB(F814W)24.5. Given the photometric redshift depth of the ALHAMBRA multiband data (=0.86) and the approximately -band selection, there is a noticeable bias against red objects at moderate redshift. We avoid this bias by creating a new catalogue selected in the band. This newly obtained catalogue is certainly shallower in terms of apparent magnitude, but deeper in terms of redshift, with a significant population of red objects at . We select objects using the band images, which reach an approximate AB magnitude limit . We generate masks and derive completeness functions to characterize the sample. We have tested the quality of the photometry and photometric redshifts using both internal and external checks. Our final catalogue includes sources down to , with a significant tail towards high redshift. We have checked that there is a large sample of objects with spectral energy distributions that correspond to that of massive, passively evolving galaxies at , reaching as far as . We have tested the possibility of combining our data with deep infrared observations at longer wavelengths, particularly Spitzer IRAC data
Improved constraints on the expansion rate of the Universe up to z~1.1 from the spectroscopic evolution of cosmic chronometers
We present new improved constraints on the Hubble parameter H(z) in the
redshift range 0.15 < z < 1.1, obtained from the differential spectroscopic
evolution of early-type galaxies as a function of redshift. We extract a large
sample of early-type galaxies (\sim11000) from several spectroscopic surveys,
spanning almost 8 billion years of cosmic lookback time (0.15 < z < 1.42). We
select the most massive, red elliptical galaxies, passively evolving and
without signature of ongoing star formation. Those galaxies can be used as
standard cosmic chronometers, as firstly proposed by Jimenez & Loeb (2002),
whose differential age evolution as a function of cosmic time directly probes
H(z). We analyze the 4000 {\AA} break (D4000) as a function of redshift, use
stellar population synthesis models to theoretically calibrate the dependence
of the differential age evolution on the differential D4000, and estimate the
Hubble parameter taking into account both statistical and systematical errors.
We provide 8 new measurements of H(z) (see Tab. 4), and determine its change in
H(z) to a precision of 5-12% mapping homogeneously the redshift range up to z
\sim 1.1; for the first time, we place a constraint on H(z) at z \neq 0 with a
precision comparable with the one achieved for the Hubble constant (about 5-6%
at z \sim 0.2), and covered a redshift range (0.5 < z < 0.8) which is crucial
to distinguish many different quintessence cosmologies. These measurements have
been tested to best match a \Lambda CDM model, clearly providing a
statistically robust indication that the Universe is undergoing an accelerated
expansion. This method shows the potentiality to open a new avenue in constrain
a variety of alternative cosmologies, especially when future surveys (e.g.
Euclid) will open the possibility to extend it up to z \sim 2.Comment: 34 pages, 15 figures, 6 tables, published in JCAP. It is a companion
to Moresco et al. (2012b, http://arxiv.org/abs/1201.6658) and Jimenez et al.
(2012, http://arxiv.org/abs/1201.3608). The H(z) data can be downloaded at
http://www.physics-astronomy.unibo.it/en/research/areas/astrophysics/cosmology-with-cosmic-chronometer
Stellar populations of galaxies in the ALHAMBRA survey up to . III. The stellar content of the quiescent galaxy population during the last Gyr
We aim at constraining the stellar population properties of quiescent
galaxies. These properties reveal how these galaxies evolved and assembled
since up to the present time. Combining the ALHAMBRA multi-filter
photo-spectra with the SED-fitting code MUFFIT, we build a complete catalogue
of quiescent galaxies via the dust-corrected stellar mass vs colour diagram.
This catalogue includes stellar population properties, such as age,
metallicity, extinction, stellar mass and photometric redshift, retrieved from
the analysis of composited populations based on two independent sets of SSP
models. We develop and apply a novel methodology to provide, for the first
time, the analytic probability distribution functions (PDFs) of mass-weighted
age, metallicity, and extinction of quiescent galaxies as a function of
redshift and stellar mass. We adopt different star formation histories to
discard potential systematics in the analysis. The number density of quiescent
galaxies is found to increase since , with a more substantial variation
at lower mass. Quiescent galaxies feature extinction , with median
values in the range . At increasing stellar mass,
quiescent galaxies are older and more metal rich since . A detailed
analysis of the PDFs reveals that the evolution of quiescent galaxies is not
compatible with passive evolution and a slight decrease is hinted at median
metallicity ~dex. The intrinsic dispersion of the age and
metallicity PDFs show a dependence with stellar mass and/or redshift. These
results are consistent with both sets of SSP models and the alternative SFH
assumptions explored. Consequently, the quiescent population must undergo an
evolutive pathway including mergers and/or remnants of star formation to
reconcile the observed trends, where the `progenitor' bias should also be taken
into account.Comment: 27 pages, 8 figures, 9 tables, accepted for publication in A&
Feline Leukemia Virus and Other Pathogens as Important Threats to the Survival of the Critically Endangered Iberian Lynx (Lynx pardinus)
BACKGROUND: The Iberian lynx (Lynx pardinus) is considered the most endangered felid species in the world. In order to save this species, the Spanish authorities implemented a captive breeding program recruiting lynxes from the wild. In this context, a retrospective survey on prevalence of selected feline pathogens in free-ranging lynxes was initiated. METHODOLOGY/ PRINCIPAL FINDINGS: We systematically analyzed the prevalence and importance of seven viral, one protozoan (Cytauxzoon felis), and several bacterial (e.g., hemotropic mycoplasma) infections in 77 of approximately 200 remaining free-ranging Iberian lynxes of the Doñana and Sierra Morena areas, in Southern Spain, between 2003 and 2007. With the exception of feline immunodeficiency virus (FIV), evidence of infection by all tested feline pathogens was found in Iberian lynxes. Fourteen lynxes were feline leukemia virus (FeLV) provirus-positive; eleven of these were antigenemic (FeLV p27 positive). All 14 animals tested negative for other viral infections. During a six-month period in 2007, six of the provirus-positive antigenemic lynxes died. Infection with FeLV but not with other infectious agents was associated with mortality (p<0.001). Sequencing of the FeLV surface glycoprotein gene revealed a common origin for ten of the eleven samples. The ten sequences were closely related to FeLV-A/61E, originally isolated from cats in the USA. Endogenous FeLV sequences were not detected. CONCLUSIONS/SIGNIFICANCE: It was concluded that the FeLV infection most likely originated from domestic cats invading the lynx's habitats. Data available regarding the time frame, co-infections, and outcome of FeLV-infections suggest that, in contrast to the domestic cat, the FeLV strain affecting the lynxes in 2007 is highly virulent to this species. Our data argue strongly for vaccination of lynxes and domestic cats in and around lynx's habitats in order to prevent further spread of the virus as well as reduction the domestic cat population if the lynx population is to be maintained