Unveiling the Active Nucleus of Centaurus A

We report new HST WFPC2 and NICMOS observations of the center of the nearest radio galaxy Centaurus A (NGC 5128) and discuss their implications for our understanding of the active nucleus and jet. We detect the active nucleus in the near-IR (K and H) and, for the first time, in the optical (I and V), deriving the spectral energy distribution of the nucleus from the radio to X-rays. The optical and part of the near-IR emission can be explained by the extrapolation of the X-ray power law reddened by A_V~14mag, a value consistent with other independent estimates. The 20pc-scale nuclear disk discovered by Schreier et al. (1998) is detected in the [FeII] 1.64mic line and presents a morphology similar to that observed in Pa alpha with a [FeII]/Pa alpha ratio typical of low ionization Seyfert galaxies and LINERs. NICMOS 3 Pa alpha observations in a 50"x50" circumnuclear region suggest enhanced star formation (~0.3Msun/yr) at the edges of the putative bar seen with ISO, perhaps due to shocks driven into the gas. The light profile, reconstructed from V, H and K observations, shows that Centaurus A has a core profile with a resolved break at ~4" and suggests a black--hole mass of ~10^9 Msun. A linear blue structure aligned with the radio/X-ray jet may indicate a channel of relatively low reddening in which dust has been swept away by the jet.Comment: 19 pages, 13 figures, Astrophysical Journal, in press. High quality figures available at http://www.arcetri.astro.it/~marconi/colpic.htm

In vitro propagation of cedar (Cedrela odorata L.) from juvenile shoots

Garriga, M (Garriga, Miguel); Caligari, PDS (Caligari, Peter D. S.). Univ Talca, Inst Biol Vegetal & Biotecnol, Talca, ChileCedrela odorata L. is one of the most important timber species currently traded in the Caribbean and Central America; however, it has been intensively exploited. In vitro techniques and clonal propagation can help to develop new plantations and assist in establishing improvement programs for this species. The aim of this study was to develop a protocol to establish in vitro conditions and to micropropagate this species from nodal explants from juvenile cuttings taken from field trees. Disinfection of node explants with 5% propiconazole CE 25 during 3 min resulted in 100% explant disinfection and 60% morphogenic response on those established explants. Shoot development was optimized by cultivating in vitro node explants in Murashige and Skoog basal medium supplemented with 2 mg L(-1) 6-bencilaminopurine and 3 mg L(-1) naphthaleneacetic acid. This medium resulted in 100% shoot development from the in vitro node explants with a 3.93 cm mean height. Rooting was also stimulated 6 wk after individualization of the regenerated plants on the same micropropagation medium with a mean of 3.9 roots per plant. In vitro plants did not show morphologic differences when compared to ex vitro seeds

The composite starburst/AGN nature of the superwind galaxy NGC 4666

We report the discovery of a Compton-thick AGN and of intense star-formation activity in the nucleus and disk, respectively, of the nearly edge-on superwind galaxy NGC 4666. Spatially unresolved emission is detected by BeppoSAX only at energies <10 keV, whereas spatially resolved emission from the whole disk is detected by XMM-Newton. A prominent (EW ~ 1-2 keV) emission line at ~6.4 keV is detected by both instruments. From the XMM-Newton data alone the line is spectrally localized at E ~ 6.42 +/- 0.03 keV, and seems to be spatially concentrated in the nuclear region of NGC 4666. This, together with the presence of a flat (Gamma ~ 1.3) continuum in the nuclear region, suggests the existence of a strongly absorbed (i.e., Compton-thick) AGN, whose intrinsic 2-10 keV luminosity is estimated to be L_{2-10} > 2 x 10^{41} erg/s. At energies <1 keV the integrated (BeppoSAX) spectrum is dominated by a ~0.25 keV thermal gas component distributed throughout the disk (resolved by XMM-Newton). At energies ~2-10 keV, the integrated spectrum is dominated by a steep (G > 2) power-law (PL) component. The latter emission is likely due to unresolved sources with luminosity L ~ 10^{38} - 10^{39} erg/s that are most likely accreting binaries (with BH masses <8 M_sun). Such binaries, which are known to dominate the X-ray point-source luminosity in nearby star-forming galaxies, have Gamma ~ 2 PL spectra in the relevant energy range. A Gamma ~ 1.8 PL contribution from Compton scattering of (the radio-emitting) relativistic electrons by the ambient FIR photons may add a truly diffuse component to the 2-10 keV emission.Comment: A&A, in press (10 pages, 14 figures.) Full gzipped psfile obtainable from http://www.bo.iasf.cnr.it/~malaguti/r_stuff.htm

Global Perspectives on Task Shifting and Task Sharing in Neurosurgery.

BACKGROUND: Neurosurgical task shifting and task sharing (TS/S), delegating clinical care to non-neurosurgeons, is ongoing in many hospital systems in which neurosurgeons are scarce. Although TS/S can increase access to treatment, it remains highly controversial. This survey investigated perceptions of neurosurgical TS/S to elucidate whether it is a permissible temporary solution to the global workforce deficit. METHODS: The survey was distributed to a convenience sample of individuals providing neurosurgical care. A digital survey link was distributed through electronic mailing lists of continental neurosurgical societies and various collectives, conference announcements, and social media platforms (July 2018-January 2019). Data were analyzed by descriptive statistics and univariate regression of Likert Scale scores. RESULTS: Survey respondents represented 105 of 194 World Health Organization member countries (54.1%; 391 respondents, 162 from high-income countries and 229 from low- and middle-income countries [LMICs]). The most agreed on statement was that task sharing is preferred to task shifting. There was broad consensus that both task shifting and task sharing should require competency-based evaluation, standardized training endorsed by governing organizations, and maintenance of certification. When perspectives were stratified by income class, LMICs were significantly more likely to agree that task shifting is professionally disruptive to traditional training, task sharing should be a priority where human resources are scarce, and to call for additional TS/S regulation, such as certification and formal consultation with a neurosurgeon (in person or electronic/telemedicine). CONCLUSIONS: Both LMIC and high-income countries agreed that task sharing should be prioritized over task shifting and that additional recommendations and regulations could enhance care. These data invite future discussions on policy and training programs

TOI-431/HIP 26013: A Super-Earth And A Sub-Neptune Transiting A Bright, Early K Dwarf, With A Third RV Planet

We present the bright (Vmag = 9.12), multiplanet system TOI-431, characterized with photometry and radial velocities (RVs). We estimate the stellar rotation period to be 30.5 ± 0.7 d using archival photometry and RVs. Transiting Exoplanet Survey Satellite (TESS) objects of Interest (TOI)-431 b is a super-Earth with a period of 0.49 d, a radius of 1.28 ± 0.04 R⊕, a mass of 3.07 ± 0.35 M⊕, and a density of 8.0 ± 1.0 g cm⁻³; TOI-431 d is a sub-Neptune with a period of 12.46 d, a radius of 3.29 ± 0.09 R⊕, a mass of 9.90 (+1.53)/(-1.49) M⊕, and a density of 1.36 ± 0.25 g cm⁻³. We find a third planet, TOI-431 c, in the High Accuracy Radial velocity Planet Searcher RV data, but it is not seen to transit in the TESS light curves. It has an Msin i of 2.83 (+0.41)/(-0.34) M⊕, and a period of 4.85 d. TOI-431 d likely has an extended atmosphere and is one of the most well-suited TESS discoveries for atmospheric characterization, while the super-Earth TOI-431 b may be a stripped core. These planets straddle the radius gap, presenting an interesting case-study for atmospheric evolution, and TOI-431 b is a prime TESS discovery for the study of rocky planet phase curves

Prevalencia de esofagitis eosinofílica: estudio multicéntrico en población pediátrica evaluada en 36 centros de gastroenterología de América Latina

Introducción y objetivo: La esofagitis eosinofílica es una enfermedad crónica, mediada inmunológicamente, descrita en series y publicaciones alrededor del mundo. En los últimos 20 años diversos estudios han intentado evaluar la incidencia y prevalencia de la enfermedad. El objetivo del presente trabajo es estimar la prevalencia de esofagitis eosinofílica en un grupo de niños atendidos en 36 centros de gastroenterología pediátrica de 10 países latinoamericanos. Materiales y métodos: A través de un protocolo multicéntrico, observacional y transversal se estimó la prevalencia de período de esofagitis eosinofílica entre los niños atendidos en consulta externa y sometidos a endoscopia superior diagnóstica por cualquier motivo en 36 centros de 10 países latinoamericanos durante un período de 3 meses. Resultados: Entre abril y junio de 2016 108 casos de esofagitis eosinofílica fueron evaluados. Asimismo, un promedio de 29,253 consultas ambulatorias y 4,152 endoscopias superiores de carácter diagnóstico fueron realizadas en los 36 centros participantes. La tasa de prevalencia de esofagitis eosinofílica en la población estudiada (n = 29,253) fue de 3,69 casos × 1,000 (IC 95%: 3.04 a 4.44) y entre los niños sometidos a endoscopia superior de rutina (n = 4,152) fue de 26 x 1,000 (IC 95%: 22.6 a 29.4). Conclusión: La tasa general de prevalencia de período de esofagitis eosinofílica en un grupo de niños evaluados en 36 centros latinoamericanos de gastroenterología pediátrica resultó de 3,69 × 1,000, y entre aquellos sometidos a endoscopia fue de 26 × 1,000. La prevalencia mostró una importante variabilidad entre los países y centros participantes. Este es el primer estudio de prevalencia de esofagitis eosinofílica pediátrica en Latinoamérica. Abstract: Introduction and objective: Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. Materials and methods: A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. Results: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n = 29,253) was 3.69 cases × 1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n = 4,152), it was 26 x 1,000 (95% CI: 22.6 to 29.4). Conclusions: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69 × 1,000, and in the children that underwent endoscopy, it was 26 × 1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America. Palabras clave: Esofagitis, Eosinofílica, Niños, Prevalencia, Latinoamérica, Keywords: Esophagitis, Eosinophilic, Children, Prevalence, Latin Americ

Role of 4-1BB Receptor in the Control Played by CD8+ T Cells on IFN-γ Production by Mycobacterium tuberculosis Antigen-Specific CD4+ T Cells

BACKGROUND: Antigen-specific IFN-gamma producing CD4(+) T cells are the main mediators of protection against Mycobacterium tuberculosis infection both under natural conditions and following vaccination. However these cells are responsible for lung damage and poor vaccine efficacy when not tightly controlled. Discovering new tools to control nonprotective antigen-specific IFN-gamma production without affecting protective IFN-gamma is a challenge in tuberculosis research. METHODS AND FINDINGS: Immunization with DNA encoding Ag85B, a candidate vaccine antigen of Mycobacterium tuberculosis, elicited in mice a low but protective CD4(+) T cell-mediated IFN-gamma response, while in mice primed with DNA and boosted with Ag85B protein a massive increase in IFN-gamma response was associated with loss of protection. Both protective and non-protective Ag85B-immunization generated antigen-specific CD8(+) T cells which suppressed IFN-gamma-secreting CD4(+) T cells. However, ex vivo ligation of 4-1BB, a member of TNF-receptor super-family, reduced the massive, non-protective IFN-gamma responses by CD4(+) T cells in protein-boosted mice without affecting the low protective IFN-gamma-secretion in mice immunized with DNA. This selective inhibition was due to the induction of 4-1BB exclusively on CD8(+) T cells of DNA-primed and protein-boosted mice following Ag85B protein stimulation. The 4-1BB-mediated IFN-gamma inhibition did not require soluble IL-10, TGF-beta, XCL-1 and MIP-1beta. In vivo Ag85B stimulation induced 4-1BB expression on CD8(+) T cells and in vivo 4-1BB ligation reduced the activation, IFN-gamma production and expansion of Ag85B-specific CD4(+) T cells of DNA-primed and protein-boosted mice. CONCLUSION/SIGNIFICANCE: Antigen-specific suppressor CD8(+) T cells are elicited through immunization with the mycobacterial antigen Ag85B. Ligation of 4-1BB receptor further enhanced their suppressive activity on IFN-gamma-secreting CD4(+) T cells. The selective expression of 4-1BB only on CD8(+) T cells in mice developing a massive, non-protective IFN-gamma response opens novel strategies for intervention in tuberculosis pathology and vaccination through T-cell co-stimulatory-based molecular targeting

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112