A deep learning system to obtain the optimal parameters for a threshold-based breast and dense tissue segmentation

[EN] Background and Objective: Breast cancer is the most frequent cancer in women. The Spanish healthcare network established population-based screening programs in all Autonomous Communities, where mammograms of asymptomatic women are taken with early diagnosis purposes. Breast density assessed from digital mammograms is a biomarker known to be related to a higher risk to develop breast cancer. It is thus crucial to provide a reliable method to measure breast density from mammograms. Furthermore the complete automation of this segmentation process is becoming fundamental as the amount of mammograms increases every day. Important challenges are related with the differences in images from different devices and the lack of an objective gold standard. This paper presents a fully automated framework based on deep learning to estimate the breast density. The framework covers breast detection, pectoral muscle exclusion, and fibroglandular tissue segmentation. Methods: A multi-center study, composed of 1785 women whose "for presentation" mammograms were segmented by two experienced radiologists. A total of 4992 of the 6680 mammograms were used as training corpus and the remaining (1688) formed the test corpus. This paper presents a histogram normalization step that smoothed the difference between acquisition, a regression architecture that learned segmentation parameters as intrinsic image features and a loss function based on the DICE score. Results: The results obtained indicate that the level of concordance (DICE score) reached by the two radiologists (0.77) was also achieved by the automated framework when it was compared to the closest breast segmentation from the radiologists. For the acquired with the highest quality device, the DICE score per acquisition device reached 0.84, while the concordance between radiologists was 0.76. Conclusions: An automatic breast density estimator based on deep learning exhibits similar performance when compared with two experienced radiologists. It suggests that this system could be used to support radiologists to ease its work.This work was partially funded by Generalitat Valenciana through I+D IVACE (Valencian Institute of Business Competitiviness) and GVA (European Regional Development Fund) supports under the project IMAMCN/2019/1, and by Carlos III Institute of Health under the project DTS15/00080.Perez-Benito, FJ.; Signol, F.; Perez-Cortes, J.; Fuster Bagetto, A.; Pollan, M.; Pérez-Gómez, B.; Salas-Trejo, D.... (2020). A deep learning system to obtain the optimal parameters for a threshold-based breast and dense tissue segmentation. Computer Methods and Programs in Biomedicine. 195:123-132. https://doi.org/10.1016/j.cmpb.2020.105668S123132195Kuhl, C. K. (2015). The Changing World of Breast Cancer. 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Impact of COVID-19 on the degree of compliance with hand hygiene: a repeated cross-sectional study

Hand hygiene (HH) is the paramount measure used to prevent healthcare associated infections. A repeated cross-sectional study was undertaken with direct observation of the degree of compliance on HH of healthcare personnel during the SARS-CoV-2 pandemic. Between, 2018-2019, 9,083 HH opportunities were considered, and 5,821 in 2020-2022. Chi squared tests were used to identify associations. The crude and adjusted odds ratios were used along with a logistic regression model for statistical analyses. Compliance on HH increased significantly (p < 0.001) from 54.5% (95% CI: 53.5, 55.5) to 70.1% (95% CI: 68.9, 71.2) during the COVID-19 pandemic. This increase was observed in four of the five key moments of HH established by the World Health Organization (WHO) (p<0.05), except at moment 4. The factors that were significantly and independently associated with compliance were the time period considered, type of healthcare-personnel, attendance at training sessions, knowledge of HH and WHO guidelines, and availability of hand disinfectant alcoholic solution in pocket format. Highest HH compliance occurred during the COVID-19 pandemic, reflecting a positive change in healthcare-personnel’s behavior regarding HH recommendations.We received funding through the Alicante Institute for Health and Biomedical Research (ISABIAL) plan for scientific and technical research and innovation project number 2021-0392

Three-dimensional cardiac fibre disorganization as a novel parameter for ventricular arrhythmia stratification after myocardial infarction

Aims: Myocardial infarction (MI) alters cardiac fibre organization with unknown consequences on ventricular arrhythmia. We used diffusion tensor imaging (DTI) of three-dimensional (3D) cardiac fibres and scar reconstructions to identify the main parameters associated with ventricular arrhythmia inducibility and ventricular tachycardia (VT) features after MI. Methods and results: Twelve pigs with established MI and three controls underwent invasive electrophysiological characterization of ventricular arrhythmia inducibility and VT features. Animal-specific 3D scar and myocardial fibre distribution were obtained from ex vivo high-resolution contrast-enhanced T1 mapping and DTI sequences. Diffusion tensor imaging-derived parameters significantly different between healthy and scarring myocardium, scar volumes, and left ventricular ejection fraction (LVEF) were included for arrhythmia risk stratification and correlation analyses with VT features. Ventricular fibrillation (VF) was the only inducible arrhythmia in 4 out of 12 infarcted pigs and all controls. Ventricular tachycardia was also inducible in the remaining eight pigs during programmed ventricular stimulation. A DTI-based 3D fibre disorganization index (FDI) showed higher disorganization within dense scar regions of VF-only inducible pigs compared with VT inducible animals (FDI: 0.36; 0.36-0.37 vs. 0.32; 0.26-0.33, respectively, P = 0.0485). Ventricular fibrillation induction required lower programmed stimulation aggressiveness in VF-only inducible pigs than VT inducible and control animals. Neither LVEF nor scar volumes differentiated between VF and VT inducible animals. Re-entrant VT circuits were localized within areas of highly disorganized fibres. Moreover, the FDI within heterogeneous scar regions was associated with the median VT cycle length per animal (R2 = 0.5320). Conclusion: The amount of scar-related cardiac fibre disorganization in DTI sequences is a promising approach for ventricular arrhythmia stratification after MI.The CNIC (Madrid, Spain) is supported by the Ministry of Science, Innovation and Universities and the Pro CNIC Foundation. The CNIC and the BSC (Barcelona, Spain) are Severo Ochoa Centers of Excellence (SEV-2015-0505 and SEV-2011-0067, respectively). This study was supported by grants from Instituto de Salud Carlos III, Fondo Europeo de Desarrollo Regional (RD12/0042/0036, CB16/11/00458), Spanish Ministry of Science, Innovation and Universities (SAF2016-80324-R, PI16/02110, and DTS17/00136), and by the European Commission [ERA-CVD Joint Call (JTC2016/APCIN-ISCIII-2016), grant#AC16/00021]. The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain), the Spanish Society of Cardiology (Dr. Pedro Zarco award) and the Heart Rhythm section of the Spanish Society of Cardiology (DFR). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health. J.A.S. is funded by the CompBioMed project, H2020-EU.1.4.1.3 European Union's Horizon 2020 research and innovation programme, grant#675451. D.G.L. has received financial support through the 'la Caixa' Fellowship Grant for Doctoral Studies, 'la Caixa' Banking Foundation, Barcelona, Spain.S

Evaluation of a program for updating recommendations about hand hygiene

Introducción. La higiene de manos (HM) es la medida más importante para prevenir las infecciones nosocomiales. El objetivo es evaluar el programa de actualización de las recomendaciones sobre HM implantado. Material y métodos. Intervenciones: marzo-octubre/2005 se realizaron sesiones de actualización sobre cuándo y cómo realizar la HM y mayo/2006 se repartió un tríptico explicativo a todos los trabajadores informando del grado de cumplimiento de las recomendaciones. Indicadores: nivel conocimientos (NC) medido con un cuestionario de cinco preguntas que se pasaba antes y después de las sesiones y se consideró respuesta inadecuada cuando se fallaban tres o más preguntas; el consumo soluciones alcohólicas (CSA) en ml/estancia agrupado en semestres desde 2004-2006; el grado cumplimiento de recomendaciones (GCR) sobre la HM medida por observación directa en dos momentos (diciembre/2005-febrero/2006 y octubre-noviembre/2006) y la prevalencia de infecciones nosocomiales (PI) y de pacientes con infección nosocomial (PPI) a partir estudios EPINE 2004-2005-2006. Resultados. La frecuencia de respuestas inadecuadas para evaluar NC pasó de un 57,5% antes a 18,9% después (p<0,001). El CSA para HM pasó de 3 ml/estancia en 2º semestre/2004 a 17 ml/estancia en 2º semestre/2006 (p<0,001). El GCR ha pasado del 31,0% al 55,6% (p<0,001). La PI y PPI han pasado del 11,4% y el 9,6% respectivamente en el 2004 al 9,4% y 8,9% en 2006 (N.S.). Conclusión. El programa está consiguiendo de manera progresiva sus objetivos ya que los tres indicadores de proceso (NC, CSA, GC) han mejorado de manera estadísticamente significativa, y los de resultado (PI y PPI) han mejorado aunque sin significación estadística.Background. Hand Hygiene (HH) is the most important measure in the prevention of nosocomial infections. The objective was to evaluate the program for updating recommendations on HH that had been introduced. Methods. Interventions: between March-October/2005 realisation of updating sessions about when and how to realize HH and May/2006 distribution of an explicative three-part document to all healthcare workers reporting on compliance with the recommendations. Indicators: level of knowledge (LK) measured with a questionnaire of five questions that was given to those attending before and after sessions, responses were considered inadequate when three or more questions were not answered; consumption of alcoholic solutions (CAS) on ml/stay grouped into semesters from 2004-2006; compliance (CO) with recommendations on HH was measured by direct observation at two times (December/2005-February/2006 and October-November/2006); and infections prevalence (IP) and patients with infection (IPP) for EPINE studies 2004-2005-2006. Results. The frequency of inadequate answers for evaluating LK has fallen from 57,5% before to 18,9% afterwards (p <0.001). The CAS for HH has passed from 3 ml/stay in 2nd semester/2004 to 17 ml/stay 2nd semester/2006 (p <0.001). The CO with HH has risen from 31,0% to 55,6% (p <0.001). The IP and IPP have risen respectively from 11,4% and 9,6% in 2004 to 9,4% and 8,9% in 2006 (N.S.). Conclusion. The program is progressively achieving its objectives as the three process indicators (LK, CAS, CO) have improved in a statistically significant way, and the indicators of results (IP and IPP) have improved but without achieving statistical significance.Proyecto de investigación financiado por el Fondo de Investigaciones Sanitarias del Ministerio de Sanidad, Nº Expte: PI0542075 y la Dirección General de Calidad de la Conselleria de Sanitat de la Generalitat Valenciana. Nº Expte: 12-2004

Immunotherapy with CAR-T cells in paediatric haematology-oncology

Despite being a rare disease, cancer is the first cause of mortality due to disease during the paediatric age in the developed countries. The current, great increase in new treatments, such as immunotherapy, constitutes a new clinical and regulatory paradigm. Cellular immunotherapy is one of these types of immunotherapy. In particular, the advanced therapy drugs with chimeric antigen receptors in the T-lymphocytes (CAR-T), and particularly the CAR-T19 cells, has opened up a new scenario in the approach to haematology tumours like acute lymphoblastic leukaemia and the B-Cell lymphomas. The approval of tisagenlecleucel and axicabtagene ciloleucel by the regulatory authorities has led to the setting up of the National Plan for Advanced Therapies-CAR-T drugs in Spain. There is evidence of, not only the advantage of identifying the centres most suitable for their administration, but also the need for these to undergo a profound change in order that their healthcare activity is extended, in some cases, to the ability for the in-house manufacture of these types of therapies. The hospitals specialised in paediatric haematology-oncology thus have the challenge of progressing towards a healthcare model that integrates cellular immunotherapy, having the appropriate capacity to manage all aspects relative to their use, manufacture, and administration of these new treatments.A pesar de ser una enfermedad rara, el cáncer es la primera causa de mortalidad por enfermedad durante la edad pediátrica en los países desarrollados. En este momento, la irrupción de nuevos tratamientos como la inmunoterapia constituye un nuevo paradigma clínico y regulatorio. Uno de estos tipos de inmunoterapia es la inmunoterapia celular. En particular, los medicamentos de terapia avanzada con receptores antigénicos quiméricos en los linfocitos T (CAR-T), y en concreto las células CAR-T19, han supuesto un nuevo escenario en el abordaje de los tumores hematológicos, como la leucemia aguda linfoblástica y los linfomas de células tipo B. La aprobación por las autoridades regulatorias de tisagenlecleucel y axicabtagene ciloleucel,ha impulsado la puesta en marcha del Plan Nacional de Terapias Avanzadas-Medicamentos CAR-T en España, evidenciándose no solo la conveniencia de identificar los centros más adecuados para su administración, sino la necesidad de que estos sufran una profunda transformación para que su actividad asistencial se extienda en algunos casos a la capacidad de fabricación propia de este tipo de terapias. Los hospitales especializados en hematooncología pediátrica tienen por tanto el reto de evolucionar hacia un modelo asistencial que integre la inmunoterapia celular,dotándose de capacidad propia para gestionar todos los aspectos relativos al uso, fabricación y administración de estos nuevos tratamientos.Fundación CRIS contra el cáncer

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

El conflicto entre cristianos y musulmanes en las relaciones de sucesos : la liberación de Buda

Este trabajo propone el análisis de una selección de textos escritos en romance sobre la derrota turca y la toma de la ciudad de Buda en 1686, que denuncian la exultante acogida popular de la noticia de las gestas cristianas en Centroeuropa, la percepción del eterno conflicto entre Oriente y Occidente y la proyección del imaginario colectivo del siglo xvii acerca de la lucha contra los infieles.This paper offers the analysis of a selection of texts, written in Romance languages, about the Turkish defeat and the conquest of the city of Buda in 1686, which provide evidence of the popular exultation at the news of the Christian achievements in Central Europe, the perception of the eternal conflict between East and West, and the projection of the seventeenth-century collective imagination regarding the struggle against the infidel

Combined fit to the spectrum and composition data measured by the Pierre Auger Observatory including magnetic horizon effects

The measurements by the Pierre Auger Observatory of the energy spectrum and mass composition of cosmic rays can be interpreted assuming the presence of two extragalactic source populations, one dominating the flux at energies above a few EeV and the other below. To fit the data ignoring magnetic field effects, the high-energy population needs to accelerate a mixture of nuclei with very hard spectra, at odds with the approximate E$^{-2}$ shape expected from diffusive shock acceleration. The presence of turbulent extragalactic magnetic fields in the region between the closest sources and the Earth can significantly modify the observed CR spectrum with respect to that emitted by the sources, reducing the flux of low-rigidity particles that reach the Earth. We here take into account this magnetic horizon effect in the combined fit of the spectrum and shower depth distributions, exploring the possibility that a spectrum for the high-energy population sources with a shape closer to E$^{-2}$ be able to explain the observations