50 research outputs found
Decision support system for cardiovascular problems
The two main lines of medical research in this project are vascular anatomy (large vessels around
the heart, coronaries and peripheral arteries) and heart chambers. Geometric models will be
constructed to aid clinical diagnosis or multiphysical modelling and simulation. Two levels of
complexity will be considered. For heart modelling, the first level will concentrate on models of the
left and right ventricular cavities for robust and efficient extraction of simple clinical indexes of
geometry, volume, mass, and wall kinetics. The second level will aim at more complex, fourchambered
models, which will be important in developing comprehensive solid and fluid models to
assist the design of medical devices
Clasificadores basados en máquinas de soporte vertical para el diagnóstico y predicción de la enfermedad de Alzheimer
En este trabajo, se estableció una metodología de soporte al diagnostico de AD, principalmente
en sus etapas MCI ocasionado por AD y demencia ocasionada por AD.
Para este fin fueron obtenidos casos clínicos de dos proyectos de investigación en demencia
del tipo AD de reconocida trayectoria: las bases de datos Alzheimer's Disease
Neuroimaging Initiative (ADNI) (www.loni.ucla.edu/ADNI) y la base de datos The
Open Access Series of Imaging Studies (OASIS) (http://www.oasis-brains.org/).
Asimismo, fueron establecidas dos tareas principales: la selección de variables predictoras
de AD y la construcción de modelos de clasificacion basados en máquinas
de soporte vectorial (SVM), entrenados a partir de las variables seleccionadas. Las
variables predictoras seleccionadas estuvieron conformadas por biomarcadores morfométricos y características socio-demográficas y neuropsicológicas. Estas variables
deberan ser útiles para la discriminación de casos clínicos en tres estados: (1) Estado
normal (generalmente personas mayores sanas);
(2) Estado MCI ocasionado por
AD; y (3) Etapa de demencia ocasionada por AD. Por otro lado, los modelos SVM
estarán enfocados a dos tareas principales: (1) Diagnóstico de AD mediante la discriminación entre sujetos sanos y sujetos con AD; y (2) Predicción de AD, orientada
a la discriminación de sujetos MCI con riesgo de convertirse a AD y sujetos MCI
sin riesgo de conversión. Asimismo, estos modelos deberán garantizar resultados
aceptables, respecto a la sensibilidad y especificidad de las tareas de clasificación.
Los resultados obtenidos en esta investigación son prometedores. Por un lado, el
subconjunto de variables seleccionadas como relevantes para el diagnóstico de AD,
tienen correlación con los resultados de investigaciones previas. Asimismo, en la
etapa de testeo, los resultados demostraron que los modelos SVM son de gran utilidad
para el soporte diagnóstico clínico de esta enfermedad, siendo capaces de discriminar
sujetos con AD de sujetos sanos (diagnóstico) con una exactitud mayor al 99% y
distinguir a los sujetos MCI con riesgo de conversión a AD de los sujetos MCI sin
riego de conversión (predicción) con una exactitud superior al 94%
Hemodynamics in the thoracic aorta using OpenFOAM: 4D PCMRI versus CFD
The aim of this work is the study of fluid dynamics models using the CFD software
OpenFOAM, an open source software allowing meshing, manipulation, simulation
and post-processing of many problems involving fluid mechanics.
The work consists of a study with OpenFOAM of a real engineering problem, namely
to analyze hemodynamics in the thoracic aorta in collaboration with CIMNE (Centre
Internacional de Metodes Numerics a l'Enginyeria) and LABSON-UPC (Laboratorio de
Sistemas Oleohidricos y Neumcos). Speci cally, the study aims to compute the
shear stress that blood causes to aorta walls
An N-Terminal Extension to UBA5 Adenylation Domain Boosts UFM1 Activation: Isoform-Specific Differences in Ubiquitin-like Protein Activation
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Modification of proteins by the ubiquitin-like protein, UFM1, requires activation of UFM1 by the E1-activating enzyme, UBA5. In humans, UBA5 possesses two isoforms, each comprising an adenylation domain, but only one containing an N-terminal extension. Currently, the role of the N-terminal extension in UFM1 activation is not clear. Here we provide structural and biochemical data on UBA5 N-terminal extension to understand its contribution to UFM1 activation. The crystal structures of the UBA5 long isoform bound to ATP with and without UFM1 show that the N-terminus not only is directly involved in ATP binding but also affects how the adenylation domain interacts with ATP. Surprisingly, in the presence of the N-terminus, UBA5 no longer retains the 1:2 ratio of ATP to UBA5, but rather this becomes a 1:1 ratio. Accordingly, the N-terminus significantly increases the affinity of ATP to UBA5. Finally, the N-terminus, although not directly involved in the E2 binding, stimulates transfer of UFM1 from UBA5 to the E2, UFC1.Marie Curie Career Integration GrantIsrael Science FoundationIsraeli Cancer Associatio
Study of angulations of visceral abdominals arteries in their abdominal aorta emergency
Recently, fenestrated, branched and stent grafts have been developed in order to treat endovascular aneurysmal pathology at the level of the aorta in the emergence of the visceral arteries. For the implantation of stents, it is necessary to have a precise planimetry of the origin and orientation of the visceral branches in order firstly to perform the correct manufacture of the endoprosthesis and secondly the placement with precision of the same. The knowledge of the emergency of the vessels of the aortic wall and its orientation knowing the angle of emergency. The data obtained for the planning of the endovascular treatment of 37 patients in order to obtain data from the descriptive point of view of this sector
Valoración de los ángulos del cuello del aneurisma de aorta abdominal. Estudio en 507 pacientes
Angulation in different planes of the neck of abdominal aortic aneurysms may be considered a limiting factor in the implantation of different prostheses in the treatment of this pathology. It is necessary to make an assessment of the angles in different planes in routine studies prior to the planning of the procedures and especially by AngioTAC. The study evaluated the measurement of 507 patients with abdominal aortic aneurysms and treated endovascular procedures and of whom the complete information was available at the level of neck angulations. In a prospective and descriptive study the situation of this aortic sector was evaluated, contributing information about the tendency in the morphological presentation of the aorta in patients with this aetiolog
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NextGEM: Next-Generation Integrated Sensing and Analytical System for Monitoring and Assessing Radiofrequency Electromagnetic Field Exposure and Health
The evolution of emerging technologies that use Radio Frequency Electromagnetic Field (RF-EMF) has increased the interest of the scientific community and society regarding the possible adverse effects on human health and the environment. This article provides NextGEM's vision to assure safety for EU citizens when employing existing and future EMF-based telecommunication technologies. This is accomplished by generating relevant knowledge that ascertains appropriate prevention and control/actuation actions regarding RF-EMF exposure in residential, public, and occupational settings. Fulfilling this vision, NextGEM commits to the need for a healthy living and working environment under safe RF-EMF exposure conditions that can be trusted by people and be in line with the regulations and laws developed by public authorities. NextGEM provides a framework for generating health-relevant scientific knowledge and data on new scenarios of exposure to RF-EMF in multiple frequency bands and developing and validating tools for evidence-based risk assessment. Finally, NextGEM's Innovation and Knowledge Hub (NIKH) will offer a standardized way for European regulatory authorities and the scientific community to store and assess project outcomes and provide access to findable, accessible, interoperable, and reusable (FAIR) data
Discrete modeling of human body using preprocessing and segmentation techniques of medical images
The generation of anatomical models is one the most important concern to biomedical researchers as well as to medical doctors, due to needed to understand the human tissues. Is know that the soft tissues like heart, brain, prostate and hard tissues like jaw, bones, skull, etc are structures of complex morphologies, so, the anatomical models generation is not an easy and trivial task. Currently, this task has benefited of advances of imaging diagnostic, which permit obtain cross and longitudinal sections of human body. In this research, we describe a method to obtain 3D discrete models of human body given by a dataset of medical images. Five main modules were implemented in prototype software: (1) Reading and 3D reconstruction of Computerized Axial Tomography and Magnetic Resonance Images. (2) Preprocessing techniques for improve the low medical images quality by using enhancement algorithms to reduce image noise and to increase structures contrast. (3) Combined segmentation techniques for tissue identification, which were applied through a multi-stage approach. (4) Post processing techniques to improve segmented volumes and (5) Exportation task of volumes to readable formats by Computer Aided Design (CAD) tools to be later analyzed by numerical methods. The performance of our method is shown on several medical examples and the techniques were validated using statistical descriptors to compare our models with models from free databases. Results showed that the implemented techniques generate precise and useful models for numerical analysis and medical survey, planning and surgery in a short processing time
Mandibular advancement devices in the treatment of obstructive sleep apnea syndrome
Obstructive sleep apnea syndrome (OSAS) consists in the occurrence of recurrent episodes of airflow limitation during sleep, with undesirable consequences for the health. The phenomenon is well known from a medical point of view (prognosis, diagnosis and treatment), but there is not a methodology or analysis tools for the quantification of the clinical response using Mandibular Advancement Devices (MAD). This paper shows how combining image processing, fluid dynamics and engineering design criteria, imported from other fields, allow to establish a simple analysis method clinically useful to decide the more convenient positioning of the MAD based on the pressure or mechanical movement of the jaw. This methodology is applied to a patient suffering OSAS which the objective to evaluate the changes provoked in the upper-airways due to an innovative mandibular device