1,719 research outputs found

    La orejuela izquierda como fuente de accidentes cerebrovasculares: cerrar (y cómo), o no cerrar (y por qué)

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    The left atrial appendage is considered the main source of emboli in strokes in patients with atrial fibrillation. Oral anticoagulant therapy significantly reduces the risk of cerebral embolic events compared to aspirin, but it is associated with bleeding complications, and is not always used. Closure of the left atrial appendage reduces the rate of thromboembolic events, and it is currently recommended in patients with atrial fibrillation submitted to mitral valve surgery. However, the formation of emboli in these patients may be due to other causes, as the role of the atrial appendage could be less important than is assumed. Moreover, not all patients are candidates for oral anticoagulation, and not all are kept in a proper therapeutic range, which could justify the formation of atrial thrombi. There are several methods for performing the closure of the appendage: direct suture in concomitant mitral surgery, epicardial exclusion by stapling or clips, or endovascular occlusion by percutaneous application. However, the results seem inconclusive with regards to their effectiveness for complete occlusion of the appendage, safety, and efficacy in preventing cerebral embolic events. To add to the confusion, some authors reveal no clear benefit in suture closure, and even describe an increased risk of thromboembolism. We present a review of left atrial appendage closure for the prevention of strokes, as well as the different procedures described above

    Cirugía de la fibrilación auricular

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    Atrial fibrillation surgery is based on creating scars in the atrium, in order to avoid re-entry phenomena that may initiate and perpetuate arrhythmia, and driving the normal stimuli from the sinus node to the atrio-ventricular node. The complexity and increased risk of the initial surgical technique, based on a "cut-and-sew" procedure, have enhanced other current procedures, in which different energies are used making it possible to perform scars in a safer and less invasive way. At present, atrial fibrillation surgery is not performed routinely in all cardiothoracic surgical centers, and there is no consensus in which is the best type of technique. Even if the results are good, they depend on multiples factors such as duration of arrhythmia, atrial size and type of technique employed. In addition, there is some variability in the description within the scientific community of the results and procedures used, which makes its analysis confusing. In this paper we review the different techniques described, the results and their application in minimally invasive surgery

    Left atrial appendage occlusion by invagination and double suture technique

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    Left atrial appendage (LAA) plays a crucial role as a source of atrial thrombus in patients with atrial fibrillation (AF). Thus, the need to close LAA becomes evident in patients with AF who undergo concomitant mitral valve surgery. Unfortunately, it has been reported a high rate of unsuccessful LAA occlusion, regardless of the technique employed.We propose a safe and simple method for LAA occlusion consisting in invagination of the appendage into the left atrium, followed by two sutures (purse string suture around the base of the LAA and a reinforce running suture)

    Úlcera penetrante de aorta ascendente en un paciente asintomático

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    La úlcera penetrante de aorta (UPA) es la ulceración de una placa aterosclerótica que afecta a la lámina elástica interna de la aorta, y que puede evolucionar hacia un hematoma de pared o una disección aórtica si se produce el paso de sangre hacia la capa media. A pesar de que se localiza más frecuentemente en la aorta descendente, puede presentar una alta mortalidad en caso de situarse en la aorta ascendente, donde la cirugía está indicada aunque el paciente se encuentre asintomático. Presentamos el caso de un paciente sin sintomatología con úlcera penetrante de aorta ascendente (UPAA) ascendente sometido a sustitución de aorta ascendente por una prótesis vascular.Penetrating aortic ulcer (PAU) has been defined as an atherosclerotic plaque ulceration that breaks the internal elastic lamina of the aorta, which may progress to a wall hematoma or aortic dissection in case of blood seeping into the middle layer. Although PAU is commonly located in the descending aorta, the involvement of the ascending aorta can be fatal. Therefore, surgery is indicated even in asymptomatic patients presenting an ascending PAU. We report on an asymptomatic patient with ascending PAU referred for replacement of the ascending aorta with a composite prosthetic graft

    Quantitative trait loci conferring grain mineral nutrient concentrations in durum wheat 3 wild emmer wheat RIL population

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    Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe

    Planck intermediate results. XXIX. All-sky dust modelling with Planck, IRAS, and WISE observations

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    We present all-sky modelling of the high resolution Planck, IRAS, and WISE infrared (IR) observations using the physical dust model presented by Draine and Li in 2007 (DL). We study the performance and results of this model, and discuss implications for future dust modelling. The present work extends the DL dust modelling carried out on nearby galaxies using Herschel and Spitzer data to Galactic dust emission. We employ the DL dust model to generate maps of the dust mass surface density, the optical extinction Av, and the starlight intensity parametrized by Umin. The DL model reproduces the observed spectral energy distribution (SED) satisfactorily over most of the sky, with small deviations in the inner Galactic disk and in low ecliptic latitude areas. We compare the DL optical extinction Av for the diffuse interstellar medium with optical estimates for 2 10^5 quasi-stellar objects (QSOs) observed in the Sloan digital sky survey. The DL Av estimates are larger than those determined towards QSOs by a factor of about 2, which depends on Umin. The DL fitting parameter Umin, effectively determined by the wavelength where the SED peaks, appears to trace variations in the far-IR opacity of the dust grains per unit Av, and not only in the starlight intensity. To circumvent the model deficiency, we propose an empirical renormalization of the DL Av estimate, dependent of Umin, which compensates for the systematic differences found with QSO observations. This renormalization also brings into agreement the DL Av estimates with those derived for molecular clouds from the near-IR colours of stars in the 2 micron all sky survey. The DL model and the QSOs data are used to compress the spectral information in the Planck and IRAS observations for the diffuse ISM to a family of 20 SEDs normalized per Av, parameterized by Umin, which may be used to test and empirically calibrate dust models.Comment: Final version that has appeared in A&

    An Overview of the 2014 ALMA Long Baseline Campaign

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    A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ~15 km. To develop and test this capability, a Long Baseline Campaign (LBC) was carried out from September to late November 2014, culminating in end-to-end observations, calibrations, and imaging of selected Science Verification (SV) targets. This paper presents an overview of the campaign and its main results, including an investigation of the short-term coherence properties and systematic phase errors over the long baselines at the ALMA site, a summary of the SV targets and observations, and recommendations for science observing strategies at long baselines. Deep ALMA images of the quasar 3C138 at 97 and 241 GHz are also compared to VLA 43 GHz results, demonstrating an agreement at a level of a few percent. As a result of the extensive program of LBC testing, the highly successful SV imaging at long baselines achieved angular resolutions as fine as 19 mas at ~350 GHz. Observing with ALMA on baselines of up to 15 km is now possible, and opens up new parameter space for submm astronomy.Comment: 11 pages, 7 figures, 2 tables; accepted for publication in the Astrophysical Journal Letters; this version with small changes to affiliation

    Clinical characteristics of vulnerable populations hospitalized and diagnosed with COVID-19 in Buenos Aires, Argentina

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    There is not in Argentina publications regarding the presentation of patients with COVID-19 requiring hospitalized and emergency care in vulnerable populations (lower incomes and less education tend at greater risk for poor health status and healthcare access), and it has few reports in developing countries. The objective is to determine whether in the care of vulnerable patients, to succeed against COVID-19, multiple public health tools and interventions will be needed to minimize morbidity and mortality. The study is a prospective cohort investigation of patients with lab-confirmed COVID-19, who required to any of the Health Centers response from April 8, 2020, to August 18, 2020. In Buenos Aires Metropolitan Area (AMBA), April 8, 2020 the virus was identified in patients hospitalized in the "Southeast Network" (SN), AMBA. SN covering an area of 661 square kilometers, with 1.8 million inhabitants residing in urban, and rural areas. A total of 14 health centers with different levels of care complexity provide care to patients in the region. The information of each patient with COVID-19 evaluated by SN, was incorporated in an Epidemiological Dashboard. The investigation was designed and reported with consideration of observational studies in epidemiology. We describe the hospitals presentation and care of persons who required SN response and were ultimately diagnosed with COVID-19. From April 8, 2020, to August 18, 2020, were included 1495 patients with lab-confirmed COVID-19 in SN. A total of 58% patients were men, and the mean age (SD) was 48.9 (15.59) years. Eighty one percent patients with pre-existing diseases, most frequent hypertension and diabetes, but hypertension, chronic lung disease, and cardiovascular disease presented higher risk. A total of 13% were hospitalized in Intensive Therapy Unit. The mortality of the cohort was 9.77%. Mortality was higher for patients aged 65 or more (OR 5.09), and for those had some pre-existing disease (OR 2.61). Our observations are consistent with reports demonstrating older persons, and those with comorbidities have the highest risk of mortality related to COVID-19. However, unlike other reports from developed or some developing countries, the mortality in our study is lower. This finding may be related to age of our cohort is younger than other published. Also, the health system was able to respond to the demand.Fil: Yacobitti, A.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Otero, L.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Doldan Arrubarrena, V.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Arano, J.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Lage, S.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Silberman, M.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Zubieta, M.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Erbetta, I.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Danei, P.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Baeck, G.. Hospital Mi Pueblo; ArgentinaFil: Vallejos, V.. No especifíca;Fil: Cavalli, F.. No especifíca;Fil: Calderón, N.. Gobierno de la Provincia de Buenos Aires. Hospital Zonal General de Agudos Doctor Lucio Melendez.; ArgentinaFil: Di Gregorio, M.. Gobierno de la Provincia de Buenos Aires. Hospital Zonal General de Agudos Doctor Lucio Melendez.; ArgentinaFil: Hernandez, V.. Hospital Dr. Arturo Oñativia - Salta Capital.; ArgentinaFil: Bruno, D.. Hospital Dr. Arturo Oñativia - Salta Capital.; ArgentinaFil: Rodera, B.. Municipalidad de Quilmes (buenos Aires). Hospital Zonal General de Agudos Doctor Isidoro Iriarte.; ArgentinaFil: Macherett, I.. Municipalidad de Quilmes (buenos Aires). Hospital Zonal General de Agudos Doctor Isidoro Iriarte.; ArgentinaFil: Parisi, M.. Municipalidad de Quilmes (buenos Aires). Hospital Zonal General de Agudos Doctor Isidoro Iriarte.; ArgentinaFil: Gallastegui, M.. Municipalidad de Quilmes (buenos Aires). Hospital Zonal General de Agudos Doctor Isidoro Iriarte.; ArgentinaFil: Paz, A.. Municipalidad de Quilmes (buenos Aires). Hospital Sub Zonal Materno Infantil Doctor Eduardo Oller.; ArgentinaFil: Bernardi, R.. No especifíca;Fil: Azcárate, S.. Gobierno de la Provincia de Buenos Aires. Hospital Provincial Evita Pueblo.; ArgentinaFil: Hraste, A.. Gobierno de la Provincia de Buenos Aires. Hospital Provincial Evita Pueblo.; ArgentinaFil: Caridi, Délida Inés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; ArgentinaFil: Boechi, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; ArgentinaFil: Salgado, P.. Universidad de Buenos Aires. Rectorado. Instituto de Investigaciones en Salud Pública; ArgentinaFil: Kochen, Sara Silvia. Gobierno de la Provincia de Buenos Aires. Hospital de Alta Complejidad Cuenca Alta Doctor Nestor Carlos Kirchner.; Argentina. Universidad Nacional Arturo Jauretche; Argentina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Planck 2015 results. XXVII. The Second Planck Catalogue of Sunyaev-Zeldovich Sources

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    We present the all-sky Planck catalogue of Sunyaev-Zeldovich (SZ) sources detected from the 29 month full-mission data. The catalogue (PSZ2) is the largest SZ-selected sample of galaxy clusters yet produced and the deepest all-sky catalogue of galaxy clusters. It contains 1653 detections, of which 1203 are confirmed clusters with identified counterparts in external data-sets, and is the first SZ-selected cluster survey containing > 10310^3 confirmed clusters. We present a detailed analysis of the survey selection function in terms of its completeness and statistical reliability, placing a lower limit of 83% on the purity. Using simulations, we find that the Y5R500 estimates are robust to pressure-profile variation and beam systematics, but accurate conversion to Y500 requires. the use of prior information on the cluster extent. We describe the multi-wavelength search for counterparts in ancillary data, which makes use of radio, microwave, infra-red, optical and X-ray data-sets, and which places emphasis on the robustness of the counterpart match. We discuss the physical properties of the new sample and identify a population of low-redshift X-ray under- luminous clusters revealed by SZ selection. These objects appear in optical and SZ surveys with consistent properties for their mass, but are almost absent from ROSAT X-ray selected samples

    Latin America: the next region for haematopoietic transplant progress

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    Haematopoietic cell transplant activity in the 28 countries comprising Latin America is poorly defined. We conducted a voluntary survey of members of the Latin American Bone Marrow Transplantation Group regarding transplant activity 2009–2012. Collated responses were compared with data of transplant rates from the Worldwide Network for Blood and Marrow Transplantation for other geographic regions. Several socio-economic variables were analysed to determine correlations with transplant rates. In total, 94 teams from 12 countries reported 11519 transplants including 7033 autotransplants and 4486 allotransplants. Annual activity increased from 2517 transplants in 2009 to 3263 in 2012, a 30% increase. Median transplants rate (transplant per million inhabitants) in 2012 was 64 (autotransplants, median 40; allotransplants, median 24). This rate is substantially lower than that in North America and European regions (482 and 378) but higher than that in the Eastern Mediterranean and Asia Pacific regions (30 and 45). However, the Latin America transplant rate is 5–8-fold lower than that in America and Europe, suggesting a need to increase transplant availability. Transplant team density in Latin America (teams per million population; 1.8) is 3–4-fold lower than that in North America (6.2) or Europe (7.6). Within Latin America, there is substantial diversity in transplant rates by country partially explained by diverse socio-economic variables including per capita gross national income, health expenditure and physician density. These data should help inform future health-care policy in Latin America
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