657 research outputs found

    Spectrophotometric Observations of Blue Compact Dwarf Galaxies: Mrk 370

    Full text link
    We present results from a detailed spectrophotometric analysis of the blue compact dwarf galaxy (BCD) Mrk 370, based on deep UBVRI broad-band and Halpha narrow-band observations, and long-slit and two-dimensional spectroscopy of its brightest knots. The spectroscopic data are used to derive the internal extinction, and to compute metallicities, electronic density and temperature in the knots. By subtracting the contribution of the underlying older stellar population, modeled by an exponential function, removing the contribution from emission lines, and correcting for extinction, we can measure the true colors of the young star-forming knots. We show that the colors obtained this way differ significantly from those derived without the above corrections, and lead to different estimates of the ages and star-forming history of the knots. Using predictions of evolutionary synthesis models, we estimate the ages of both the starburst regions and the underlying stellar component. We found that we can reproduce the colors of all the knots with an instantaneous burst of star formation and the Salpeter initial mass function with an upper mass limit of 100 solar masses. The resulting ages range between 3 and 6 Myrs. The colors of the low surface brightness component are consistent with ages larger than 5 Gyr. The kinematic results suggest ordered motion around the major axis of the galaxy.Comment: 26 pages with 14 figures; accepted for publication in Ap

    Design and rationale of a multicentre, randomised, double-blind, placebo-controlled clinical trial to evaluate the effect of vitamin D on ventricular remodelling in patients with anterior myocardial infarction: the VITamin D in Acute Myocardial Infarction (VITDAMI) trial

    Get PDF
    Introduction:Decreased plasma vitamin D (VD) levels are linked to cardiovascular damage. However, clinical trials have not demonstrated a benefit of VD supplements on left ventricular (LV) remodelling. Anterior ST-elevation acute myocardial infarction (STEMI) is the best human model to study the effect of treatments on LV remodelling. We present a proof-of-concept study that aims to investigate whether VD improves LV remodelling in patients with anterior STEMI. Methods and analysis:The VITamin D in Acute Myocardial Infarction (VITDAMI) trial is a multicentre, randomised, double-blind, placebo-controlled trial. 144 patients with anterior STEMI will be assigned to receive calcifediol 0.266 mg capsules (Hidroferol SGC)/15 days or placebo on a 2:1 basis during 12 months. Primary objective:to evaluate the effect of calcifediol on LV remodelling defined as an increase in LV end-diastolic volume >= 10\% (MRI). Secondary objectives:change in LV end-diastolic and end-systolic volumes, ejection fraction, LV mass, diastolic function, sphericity index and size of fibrotic area; endothelial function; plasma levels of aminoterminal fragment of B-type natriuretic peptide, galectin-3 and monocyte chemoattractant protein-1; levels of calcidiol (VD metabolite) and other components of mineral metabolism (fibroblast growth factor-23 (FGF-23), the soluble form of its receptor klotho, parathormone and phosphate). Differences in the effect of VD will be investigated according to the plasma levels of FGF-23 and klotho. Treatment safety and tolerability will be assessed. This is the first study to evaluate the effect of VD on cardiac remodelling in patients with STEMI. Ethics and dissemination: This trial has been approved by the corresponding Institutional Review Board (IRB) and National Competent Authority (Agencia Espanola de Medicamentos y Productos Sanitarios (AEMPS)). It will be conducted in accordance with good clinical practice (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use-Good Clinical Practice (ICH-GCP)) requirements, ethical principles of the Declaration of Helsinki and national laws. The results will be submitted to indexed medical journals and national and international meetings.The VITDAMI trial is an investigator initiated study, sponsored by the Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS-FJD). Funding has been obtained from Fondo de Investigaciones Sanitarias (PI14/01567; http://www.isciii.es/) and Spanish Society of Cardiology (http://secardiologia.es/). In addition, the study medication has been provided freely by the pharmaceutical Company FAES FARMA S.A. (Leioa, Vizcaya, Spain; http://faesfarma.com/). This company was the only funder who collaborated in study design (IG-H).S

    Maquina Verde - El Arca Solar Decathlon Latin America & Caribbean 2019

    Get PDF
    The current supply of social housing in Latin American countries is often not adequate for the real needs of the population, generating situations of social conflict and permanent contraposition between the “formal” and the “informal” cities. The Pontificia Universidad Javeriana of Bogotá and the Politecnico di Torino participated together in the Solar Decathlon Latin America and Caribbean 2019 competition with the project Máquina Ver-de - El Arca, a vivienda social thought for the informal neighborhood of El Pozón, located in the periphery of the Colombian city of Cartagena de Indias. The project is based on the reinterpretation of the Caribbean house, starting from a study of the user needs, integrating industrial technologies - like the steel frame- and artisanal technologies -such as the tejidos in the façade-, with a strategy to reduce the environmental impact of the building in its life cycle. In December 2019 Máquina Verde - El Arca was built and tested by the students and professors of the two universities during the final phase of the Solar Decathlon in Cali, Colombia. The collaboration in the international competition was born as an innovative training activity based on PBL (Problem Based Learning) and “learning by doing” methodologies and has evolved into a shared research about the issues of environmental, social and economic sustainability for the architecture of social interest of the Latin American cities

    Deep Near Infrared Mapping of Young and Old Stars in Blue Compact Dwarf Galaxies

    Full text link
    We analyze J, H and Ks near-infrared data for 9 Blue Compact Dwarf (BCD) galaxies, selected from a larger sample that we have already studied in the optical. We present contour maps, surface brightness and color profiles, as well as color maps of the sample galaxies. The morphology of the BCDs in the NIR has been found to be basically the same as in the optical. The inner regions of these systems are dominated by the starburst component. At low surface brightness levels the emission is due to the underlying host galaxy; the latter is characterized by red, radially constant colors and isophotes well fit by ellipses. We derive accurate optical near--infrared host galaxy colors for eight of the sample galaxies; these colors are typical of an evolved stellar population. Interestingly, optical near--infrared color maps reveal the presence of a complex, large-scale absorption pattern in three of the sample galaxies. We study the applicability of the Sersic law to describe the surface brightness profiles of the underlying host galaxy, and find that, because of the limited surface brightness interval over which the fit can be made, the derived Sersic parameters are very sensitive to the selected radial interval and to errors in the sky subtraction. Fitting an exponential model gives generally more stable results, and can provide a useful tool to quantify the structural properties of the host galaxy and compare them with those of other dwarf classes as well as with those of star-forming dwarfs at higher redshifts.Comment: 49 pages, 9 figures, 10 tables, accepted for publication in the Astrophysical Journa

    Development and internal validation of a multifactorial risk prediction model for gallbladder cancer in a high-incidence country

    Get PDF
    Since 2006, Chile has been implementing a gallbladder cancer (GBC) prevention program based on prophylactic cholecystectomy for gallstone patients aged 35 to 49 years. The effectiveness of this prevention program has not yet been comprehensively evaluated. We conducted a retrospective study of 473 Chilean GBC patients and 2137 population-based controls to develop and internally validate three GBC risk prediction models. The Baseline Model accounted for gallstones while adjusting for sex and birth year. Enhanced Model I also included the non-genetic risk factors: body mass index, educational level, Mapuche surnames, number of children and family history of GBC. Enhanced Model II further included Mapuche ancestry and the genotype for rs17209837. Multiple Cox regression was applied to assess the predictive performance, quantified by the area under the precision-recall curve (AUC-PRC) and the number of cholecystectomies needed (NCN) to prevent one case of GBC at age 70 years. The AUC-PRC for the Baseline Model (0.44%, 95%CI 0.42-0.46) increased by 0.22 (95%CI 0.15-0.29) when non-genetic factors were included, and by 0.25 (95%CI 0.20-0.30) when incorporating non-genetic and genetic factors. The overall NCN for Chileans with gallstones (115, 95%CI 104-131) decreased to 92 (95%CI 60-128) for Chileans with a higher risk than the median according to Enhanced Model I, and to 80 (95%CI 59-110) according to Enhanced Model II. In conclusion, age, sex and gallstones are strong risk factors for GBC, but consideration of other non-genetic factors and individual genotype data improves risk prediction and may optimize allocation of financial resources and surgical capacity.Fil: Boekstegers, Felix. Ruprecht Karls Universitat Heidelberg; AlemaniaFil: Scherer, Dominique. Ruprecht Karls Universitat Heidelberg; AlemaniaFil: Barahona Ponce, Carol. Ruprecht Karls Universitat Heidelberg; AlemaniaFil: Marcelain, Katherine. Universidad de Chile; ChileFil: Gárate Calderón, Valentina. Universidad de Chile; ChileFil: Waldenberger, Melanie. No especifíca;Fil: Morales, Erik. Universidad Católica de Maule; ChileFil: Rojas, Armando. Universidad Católica de Maule; ChileFil: Munoz, César. Universidad Católica de Maule; ChileFil: Retamales, Javier. Instituto Nacional del Cáncer; ChileFil: de Toro, Gonzalo. Universidad Austral de Chile; ChileFil: Barajas, Olga. Universidad de Chile; ChileFil: Rivera, María Teresa. Hospital del Salvador; ChileFil: Cortés, Analía. Hospital del Salvador; ChileFil: Loader, Denisse. Hospital Padre Hurtado; ChileFil: Saavedra, Javiera. Hospital Padre Hurtado; ChileFil: Gutiérrez, Lorena. Hospital San Juan de Dios; ChileFil: Ortega, Alejandro. Hospital Regional; ChileFil: Bertrán, Maria Enriqueta. Hospital Base de Valdivia; ChileFil: Bartolotti, Leonardo. Hospital Base de Valdivia; ChileFil: Gabler, Fernando. Hospital Clínico San Borja Arriarán; ChileFil: Campos, Mónica. Hospital Clínico San Borja Arriarán; ChileFil: Alvarado, Juan. Hospital Regional de Concepción - Dr. Guillermo Grant Benavente; ChileFil: Moisán, Fabricio. Hospital Regional de Concepción - Dr. Guillermo Grant Benavente; ChileFil: Spencer, Loreto. Hospital Regional de Concepción - Dr. Guillermo Grant Benavente; ChileFil: Nervi, Bruno. No especifíca;Fil: Carvajal Hausdorf, Daniel. Universidad del Desarrollo; ChileFil: Losada, Héctor. Universidad de La Frontera; ChileFil: Almau, Mauricio. Hospital de Rancagua; ChileFil: Fernández, Plinio. Hospital de Rancagua; ChileFil: Olloquequi, Jordi. Universidad de Barcelona; EspañaFil: Fuentes Guajardo, Macarena. Universidad de Tarapacá; ChileFil: Gonzalez-Jose, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Ciencias Sociales y Humanas; ArgentinaFil: Bortolini, Maria Cátira. Universidade Federal do Rio Grande do Sul; BrasilFil: Acuña Alonzo, Victor. No especifíca;Fil: Gallo, Carla. Universidad Peruana Cayetano Heredia; PerúFil: Ruiz-Linares, Andres. Colegio Universitario de Londres; Reino UnidoFil: Rothhammer, Francisco. Universidad de Tarapacá; ChileFil: Lorenzo Bermejo, Justo. Ruprecht Karls Universitat Heidelberg; Alemani

    Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years

    Get PDF
    publishersversionPeer reviewe

    Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

    Get PDF
    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

    Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

    Get PDF
    There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

    Get PDF
    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

    Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

    Get PDF
    Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia
    corecore