Hubble Space Telescope Imaging of the CFRS and LDSS Redshift Surveys---III. Field elliptical galaxies at 0.2 < z < 1.0

Surface photometry has been performed on a sample of 46 field elliptical galaxies. These galaxies are described well by a deVaucouleurs R^{1/4} profile. The sample was selected from the combined Canada-France and LDSS redshift surveys and spans the range 0.20 < z < 1.00. The relationship between galaxy half-light radius and luminosity evolves such that a galaxy of a given size is more luminous by Delta M_B=-0.97 \pm 0.14 mag at z=0.92 and the mean rest-frame color shifts blueward by Delta (U-V) =-0.68 \pm 0.11 at z=0.92 relative to the local cluster relations. Approximately 1/3 of these elliptical galaxies exhibit [OII] 3727 emission lines with equivalent widths > 15 angstroms indicating ongoing star formation. Estimated star-formation rates imply that \le 5% of the stellar mass in the elliptical galaxy population has been formed since z=1. We see no evidence for a decline in the space density of early-type galaxies with look-back time. The statistics and a comparison with local luminosity functions are both consistent with the view that the population of massive early-type galaxies was largely in place by z~1. This implies that merging is not required since that time to produce the present-day space density of elliptical galaxies.Comment: 21 pages plus 8 figures plus 5 tables. Accepted by Astrophysical Journa

Formation and Evolution of Early-Type Galaxies: Spectro-Photometry from Cosmo-Chemo-Dynamical Simulations

One of the major challenges in modern astrophysics is to understand the origin and the evolution of galaxies, the bright, massive early type galaxies (ETGs) in particular. Therefore, these galaxies are likely to be good probes of galaxy evolution, star formation and, metal enrichment in the early Universe. In this context it is very important to set up a diagnostic tool able to combine results from chemo-dynamical N-Body-TSPH (NB-TSPH) simulations of ETGs with those of spectro-photometric population synthesis and evolution so that all key properties of galaxies can be investigated. The main goal of this paper is to provide a preliminary validation of the software package before applying it to the analysis of observational data. The galaxy models in use where calculated by the Padova group in two different cosmological scenarios: the SCDM, and the Lambda CDM. For these models, we recover their spectro-photometric evolution through the entire history of the Universe. We computed magnitudes and colors and their evolution with the redshift along with the evolutionary and cosmological corrections for the model galaxies at our disposal, and compared them with data for ETGs taken from the COSMOS and the GOODS databases. Starting from the dynamical simulations and photometric models at our disposal, we created synthetic images from which we derived the structural and morphological parameters. The theoretical results are compared with observational data of ETGs selected form the SDSS database. The simulated colors for the different cosmological scenarios follow the general trend shown by galaxies of the COSMOS and GOODS. Within the redshift range considered, all the simulated colors reproduce the observational data quite well.Comment: 28 pages, 28 figures, accepted for pubblication by A&

Population based prostate cancer screening in north Mexico reveals a high prevalence of aggressive tumors in detected cases

Background: Prostate Cancer (PCa) is the second most frequent neoplasia in men worldwide. Previous reports suggest that the prevalence of PCa in Hispanic males is lower than in Africans (including communities with African ancestry) and Caucasians, but higher than in Asians. Despite these antecedents, there are few reports of open population screenings for PCa in Latin American communities. This article describes the results of three consecutive screenings in the urban population of Monterrey, Mexico. Methods: After receiving approval from our University Hospital's Internal Review Board (IRB), the screening was announced by radio, television, and press, and it was addressed to male subjects over 40 years old in general. Subjects who consented to participate were evaluated at the primary care clinics of the University Health Program at UANL, in the Metropolitan area of Monterrey. Blood samples were taken from each subject for prostate specific antigen (PSA) determination; they underwent a digital rectal examination (DRE), and were subsequently interviewed to obtain demographic and urologic data. Based on the PSA (>4.0 ng/ml) and DRE results, subjects were appointed for transrectal biopsy (TRB). Results: A total of 973 subjects were screened. Prostate biopsy was recommended to 125 men based on PSA values and DRE results, but it was performed in only 55 of them. 15 of these biopsied men were diagnosed with PCa, mostly with Gleason scores ≥ 7. Conclusion: Our results reflect a low prevalence of PCa in general, but a high occurrence of high grade lesions (Gleason ≥ 7) among patients that resulted positive for PCa. This observation remarks the importance of the PCa screening programs in our Mexican community and the need for strict follow-up campaigns

Population based prostate cancer screening in north Mexico reveals a high prevalence of aggressive tumors in detected cases

Background: Prostate Cancer (PCa) is the second most frequent neoplasia in men worldwide. Previous reports suggest that the prevalence of PCa in Hispanic males is lower than in Africans (including communities with African ancestry) and Caucasians, but higher than in Asians. Despite these antecedents, there are few reports of open population screenings for PCa in Latin American communities. This article describes the results of three consecutive screenings in the urban population of Monterrey, Mexico. Methods: After receiving approval from our University Hospital's Internal Review Board (IRB), the screening was announced by radio, television, and press, and it was addressed to male subjects over 40 years old in general. Subjects who consented to participate were evaluated at the primary care clinics of the University Health Program at UANL, in the Metropolitan area of Monterrey. Blood samples were taken from each subject for prostate specific antigen (PSA) determination; they underwent a digital rectal examination (DRE), and were subsequently interviewed to obtain demographic and urologic data. Based on the PSA (>4.0 ng/ml) and DRE results, subjects were appointed for transrectal biopsy (TRB). Results: A total of 973 subjects were screened. Prostate biopsy was recommended to 125 men based on PSA values and DRE results, but it was performed in only 55 of them. 15 of these biopsied men were diagnosed with PCa, mostly with Gleason scores ≥ 7. Conclusion: Our results reflect a low prevalence of PCa in general, but a high occurrence of high grade lesions (Gleason ≥ 7) among patients that resulted positive for PCa. This observation remarks the importance of the PCa screening programs in our Mexican community and the need for strict follow-up campaigns

Translation without eIF2 Promoted by Poliovirus 2A Protease

Poliovirus RNA utilizes eIF2 for the initiation of translation in cell free systems. Remarkably, we now describe that poliovirus translation takes place at late times of infection when eIF2 is inactivated by phosphorylation. By contrast, translation directed by poliovirus RNA is blocked when eIF2 is inactivated at earlier times. Thus, poliovirus RNA translation exhibits a dual mechanism for the initiation of protein synthesis as regards to the requirement for eIF2. Analysis of individual poliovirus non-structural proteins indicates that the presence of 2Apro alone is sufficient to provide eIF2 independence for IRES-driven translation. This effect is not observed with a 2Apro variant unable to cleave eIF4G. The level of 2Apro synthesized in culture cells is crucial for obtaining eIF2 independence. Expression of the N-or C-terminus fragments of eIF4G did not stimulate IRES-driven translation, nor provide eIF2 independence, consistent with the idea that the presence of 2Apro at high concentrations is necessary. The finding that 2Apro provides eIF2-independent translation opens a new and unsuspected area of research in the field of picornavirus protein synthesis

Value of Early Circulating Tumor Cells Dynamics to Estimate Docetaxel Benefit in Metastatic Castration-Resistant Prostate Cancer (mCRPC) Patients.

Circulating tumor cell (CTC) enumeration and changes following treatment have been demonstrated to be superior to PSA response in determining mCRPC outcome in patients receiving AR signaling inhibitors but not taxanes. We carried out a pooled analysis of two prospective studies in mCRPC patients treated with docetaxel. CTCs were measured at baseline and 3-6 weeks post treatment initiation. Cox regression models were constructed to compare 6-month radiographical progression-free survival (rPFS), CTCs and PSA changes predicting outcome. Among the subjects, 80 and 52 patients had evaluable baseline and post-treatment CTC counts, respectively. A significant association of higher baseline CTC count with worse overall survival (OS), PFS and time to PSA progression (TTPP) was observed. While CTC response at 3-6 weeks (CTC conversion (from ≥5 to p < 0.005), the association was not significant for PSA30 or PSA50 response. CTC and PSA response were discordant in over 50% of cases, with outcome driven by CTC response in these patients. The c-index values for OS were superior for early CTC changes compared to PSA response endpoints, and similar to 6-month rPFS. Early CTC declines were good predictors of improved outcomes in mCRPC patients treated with docetaxel in this small study, offering a superior and/or earlier estimation of docetaxel benefit in comparison to PSA or rPFS that merits further confirmation in larger studies