Aims. We aim at constraining the stellar population properties of quiescent galaxies. These properties reveal how these galaxies evolved and assembled since z ∼ 1 up to the present time. Methods. ...Combining the ALHAMBRA multi-filter photo-spectra with the fitting code for spectral energy distribution MUFFIT (MUlti-Filter FITting), we built 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 simple stellar population (SSP) models. We developed and applied 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 adopted different star formation histories to discard potential systematics in the analysis. Results. The number density of quiescent galaxies is found to increase since z ∼ 1, with a more substantial variation at lower stellar mass. Quiescent galaxies feature extinction AV < 0.6, with median values in the range AV = 0.15–0.3. At increasing stellar mass, quiescent galaxies are older and more metal rich since z ∼ 1. A detailed analysis of the PDFs reveals that the evolution of quiescent galaxies is not compatible with passive evolution and a slight decrease of 0.1–0.2 dex is hinted at median metallicity. The intrinsic dispersion of the age and metallicity PDFs show a dependence on stellar mass and/or redshift. These results are consistent with both sets of SSP models and assumptions of alternative star formation histories 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.
Aims: We present MUFFIT, a new generic code optimized to retrieve the main stellar population parameters of galaxies in photometric multi-filter surveys, and check its reliability and feasibility ...with real galaxy data from the ALHAMBRA survey.Methods: Making use of an error-weighted χ2-test, we compare the multi-filter fluxes of galaxies with the synthetic photometry of mixtures of two single stellar populations at different redshifts and extinctions, to provide the most likely range of stellar population parameters (mainly ages and metallicities), extinctions, redshifts, and stellar masses. To improve the diagnostic reliability, MUFFIT identifies and removes from the analysis those bands that are significantly affected by emission lines. The final parameters and their uncertainties are derived by a Monte Carlo method, using the individual photometric uncertainties in each band. Finally, we discuss the accuracies, degeneracies, and reliability of MUFFIT using both simulated and real galaxies from ALHAMBRA, comparing with results from the literature.Results: MUFFIT is a precise and reliable code to derive stellar population parameters of galaxies in ALHAMBRA. Using the results from photometric-redshift codes as input, MUFFIT improves the photometric-redshift accuracy by ~10-20%. MUFFIT also detects nebular emissions in galaxies, providing physical information about their strengths. The stellar masses derived from MUFFIT show excellent agreement with the COSMOS and SDSS values. In addition, the retrieved age-metallicity locus for a sample of z ≤ 0.22 early-type galaxies in ALHAMBRA at different stellar mass bins are in very good agreement with the ones from SDSS spectroscopic diagnostics. Moreover, a one-to-one comparison between the redshifts, ages, metallicities, and stellar masses derived spectroscopically for SDSS and by MUFFIT for ALHAMBRA reveals good qualitative agreements in all the parameters, hence reinforcing the strengths of multi-filter galaxy data and optimized analysis techniques, like MUFFIT, to conduct reliable stellar population studies.
To estimate the population frequency of uveitis complications and to evaluate their main risk factors in the patients with uveitis from the UVECAM study.
Development of complications in 386 patients ...with uveitis in the whole health area of the province of Toledo (UVECAM study) during a period of 1 year. Description of complications and study of their possible determinants by means of multivariate regression models.
Information on the development of complications was available in 371 of the 386 patients of the UVECAM study. The most frequent complications were posterior synechiae (19.0%), ocular hypertension (14.0%), macular edema (7.5%), epirretinal membrane (6.9%), glaucoma (6.6%), iridian atrophy (5.6%) and cataract (5.5%). The risk of complications increases with age, intermediate and panuveitis locations, and those of chronic or recurrent evolution.
Uveitis is associated with a high frequency of complications, especially in older patients, with intermediate or posterior localization of the inflammatory process and chronic or recurrent evolution.
Estimar la frecuencia poblacional de complicaciones de uveítis y evaluar sus principales factores de riesgo en los pacientes con uveítis del estudio UVECAM.
Desarrollo de complicaciones de los 386 pacientes con uveítis de toda el área sanitaria de la provincia de Toledo (estudio UVECAM) durante el periodo de 1 año. Descripción de complicaciones y estudio de los posibles determinantes mediante modelos de regresión multivariante.
Se dispuso de información sobre el desarrollo de complicaciones en 371 de los 386 pacientes del estudio. El 45,8% de los pacientes presentó al menos una complicación siendo las más frecuentes las sinequias posteriores (19,0%), hipertensión ocular (14,0%), edema macular (7,5%), membrana epirretiniana (6,9%), glaucoma (6,6%), atrofia iridiana (5,6%) y cataratas (5,5%). El riesgo de complicaciones aumenta con la edad, las formas intermedias y panuveítis y las de evolución crónica o recurrente.
Las uveítis se asocian con una elevada frecuencia de complicaciones especialmente en pacientes de edad avanzada, con localización intermedia o posterior del proceso inflamatorio y evolución crónica o recurrente.
Aims.
We aim at constraining the stellar population properties of quiescent galaxies. These properties reveal how these galaxies evolved and assembled since
z
∼ 1 up to the present time.
Methods.
...Combining the ALHAMBRA multi-filter photo-spectra with the fitting code for spectral energy distribution MUFFIT (MUlti-Filter FITting), we built 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 simple stellar population (SSP) models. We developed and applied 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 adopted different star formation histories to discard potential systematics in the analysis.
Results.
The number density of quiescent galaxies is found to increase since
z
∼ 1, with a more substantial variation at lower stellar mass. Quiescent galaxies feature extinction
A
V
< 0.6, with median values in the range
A
V
= 0.15–0.3. At increasing stellar mass, quiescent galaxies are older and more metal rich since
z
∼ 1. A detailed analysis of the PDFs reveals that the evolution of quiescent galaxies is not compatible with passive evolution and a slight decrease of 0.1–0.2 dex is hinted at median metallicity. The intrinsic dispersion of the age and metallicity PDFs show a dependence on stellar mass and/or redshift. These results are consistent with both sets of SSP models and assumptions of alternative star formation histories 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.
Short-chain carboxylic acids (SCCAs) produced by gut microbial fermentation may reflect gastrointestinal health. Their concentrations in serum and urine are indicative of specific metabolic pathway ...activity; therefore, accurate quantitation of SCCAs in different biofluids is desirable. However, it is often challenging to quantitate SCCAs since matrix effects, induced by the presence of a vast variety of other compounds other than SCCAs in complex biofluids, can suppress or enhance signals. Materials used for sample preparation may introduce further analytical challenges. This study reports for the first time a LC-MS/MS-based method to quantitate ten SCCAs (lactate, acetate, 2-hydroxybutyrate, propionate, isobutyrate, butyrate, 2-methylbutyrate, isovalerate, valerate and hexanoate) and evaluates the matrix effects in five human biofluids: serum, urine, stool, and contents from the duodenum and intestinal stoma bags. The optimized method, using 3-Nitrophenylhydrazone as a derivatization agent and a Charge Surface Hybrid reverse phase column, showed clear separation for all SCCAs at a concentration range of 0.1−100 µM, in a 10.5 min run without carry-over effects. The validation of the method showed a good linearity (R2 > 0.99), repeatability (CV ≤ 15%) assessed by intra- and inter-day monitoring. The lowest limit of detection (LLOD) was 25 nM and lowest limit of quantitation (LLOQ) was 50 nM for nine SCCA except acetate at 0.5 and 1 µM, respectively. Quantitative accuracy in all biofluids for most compounds was < ±15%. In summary, this methodology has the advantages over other techniques for its simple and fast sample preparation and a high level of selectivity, repeatability and robustness for SCCA quantification. It also reduced interferences from the matrix or sample containers, making it ideal for use in high-throughput analyses of biofluid samples from large-scale studies.
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•Improved LC-MS/MS-based quantitation of short-chain carboxylic acids.•Comprehensively evaluated matrix effects of human biofluids and intestinal content.•Optimized for high-throughput analyses of human biofluids from large-scale studies.
The aim of the study was to describe the clinical drivers that lead physicians to perform imaging tests in search of metastasis in non-metastasic castration prostate resistant cancer (nmCRPC) ...patients.
Observational, cross-sectional study conducted at the Departments of Urology of 38 Spanish hospitals. The study included 188 patients diagnosed with nmCRPC who underwent an imaging test for the assessment of metástasis. In one study visit, physicians were requested to specify the clinical factors that led them to perform these tests. The results of the imaging tests and the clinical characteristics of the patients since the time of prostate cancer (PC) diagnosis, were reported. Regression analyses were used to determine predictors of imaging test results.
Prostate-specific antigen (PSA) level was the most important driver to order imaging tests (57.1%), followed by regular follow-up (16.5%) and PSA doubling time (PSADT) (12.0%). Although these drivers were not associated to detection of metastasis, patients with PSA levels ≥20 ng/mL had a greater risk of metastasis than patients with PSA levels <4 ng/mL (p = 0.004) and CRPC patients diagnosed with metastasis (mCRPC) had higher median PSA levels (20.9; interquartile range IQR: 6.7–38.6) than nmCRPC (9.1; IQR: 5.0–18.0) (p = 0.005). Sixty-six percent of the patients did not undergo any imaging test after CRPC diagnosis until the study visit (10.6, IQR: 4.0−19.5 months). Curative-intent treatment at PC diagnosis and Gleason score predicted longer time from PC to CRPC diagnosis.
Physicians based their decisions to order imaging tests for metastasis detection in nmCRPC patients mainly on PSA and PSA kinetics, including the regular follow-up stated by guideline recommendations.
El objetivo del estudio consistió en describir los factores clínicos que llevan a los médicos a realizar pruebas de imagen para identificar metástasis en pacientes con cáncer de próstata (CP) resistente a la castración no metastásico (CPRCnm).
Estudio observacional transversal realizado en los servicios de Urología de 38 hospitales españoles; 188 pacientes diagnosticados con CPRCnm sometidos una prueba de imagen para evaluar la presencia de metástasis fueron incluidos. Se solicitó a los médicos, en una única visita del estudio, que especificaran los factores clínicos que los llevaron a realizar estas pruebas. Se presentaron los resultados de las pruebas de imagen y las características clínicas de los pacientes desde el diagnóstico de CP. Se utilizaron análisis de regresión para determinar factores predictivos de los resultados de las pruebas de imagen.
El valor del «prostate-specific antigen» (por sus siglas en inglés, PSA), fue el factor más importante que determinó la solicitud de pruebas de imagen (57,1%), seguido de un seguimiento habitual (16,5%) y del tiempo de duplicación del PSA (TDPSA) (12,0%). Aunque estos factores no guardaron relación con la detección de metástasis, los pacientes con una concentración de PSA ≥20 ng/mL tuvieron un mayor riesgo de metástasis que aquellos con una concentración <4 ng/mL (p = 0,004), mientras que los pacientes con CPRC diagnosticados de metástasis (CPRCm) tuvieron una mayor mediana de concentración de PSA (20,9; intervalo intercuartílico IIC: 6,7–38,6) que aquellos con CPRCnm (9,1; IIC: 5,0–18,0) (p = 0,005). Un 66% no se sometió a ninguna prueba de imagen entre el diagnóstico de CPRC y la visita del estudio (10,6, IIC: 4,0–19,5 meses). El tratamiento con intención curativa en el momento del diagnóstico de CP y la puntuación de Gleason predijeron un mayor tiempo transcurrido entre los diagnósticos de CP y CPRC.
Los médicos basaron sus decisiones de solicitar pruebas de imagen para detectar metástasis en pacientes con CPRCnm principalmente en el PSA y su cinética, incluido el seguimiento habitual establecido por las guías clínicas.
Vitreous coatings of the SiO(2)-CaO system have been prepared on Ti6Al4V substrates by the sol-gel method. The textural parameters (porosity and roughness) and thickness of the films obtained ...increase when the concentration of the precursor solutions is raised. In vitro studies of these coatings have been performed using two approaches: soaking in simulated body fluid, and by growing osteoblasts on these materials. The results of both studies show differences in terms of chemical reactivity. While in simulated body fluid the coatings were dissolved without forming a bioactive surface, when osteoblast-like cells grew on the coatings they were more stable. Furthermore, cell culture assays show biocompatible behavior of these coatings making them of potential interest for clinical applications. The effect of the textural parameters of the obtained coatings on the cell functions (attachment, spreading, proliferation and differentiation) has also been studied. The results show an increase in these cell parameters as the roughness and porosity of the coatings increase.
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