title: Brain metabolic pattern analysis using a magnetic resonance spectra classification software in experimental stroke.
abstract: Magnetic resonance spectroscopy (MRS) provides non-invasive information about the metabolic pattern of the brain parenchyma in vivo. The SpectraClassifier software performs MRS pattern-recognition by determining the spectral features (metabolites) which can be used objectively to classify spectra. Our aim was to develop an Infarct Evolution Classifier and a Brain Regions Classifier in a rat model of focal ischemic stroke using SpectraClassifier.
  
  
  
  A total of 164 single-voxel proton spectra obtained with a 7 Tesla magnet at an echo time of 12 ms from non-infarcted parenchyma, subventricular zones and infarcted parenchyma were analyzed with SpectraClassifier ( http://gabrmn.uab.es/?q=sc ). The spectra corresponded to Sprague-Dawley rats (healthy rats, n = 7) and stroke rats at day 1 post-stroke (acute phase, n = 6 rats) and at days 7 ± 1 post-stroke (subacute phase, n = 14). In the Infarct Evolution Classifier, spectral features contributed by lactate + mobile lipids (1.33 ppm), total creatine (3.05 ppm) and mobile lipids (0.85 ppm) distinguished among non-infarcted parenchyma (100% sensitivity and 100% specificity), acute phase of infarct (100% sensitivity and 95% specificity) and subacute phase of infarct (78% sensitivity and 100% specificity). In the Brain Regions Classifier, spectral features contributed by myoinositol (3.62 ppm) and total creatine (3.04/3.05 ppm) distinguished among infarcted parenchyma (100% sensitivity and 98% specificity), non-infarcted parenchyma (84% sensitivity and 84% specificity) and subventricular zones (76% sensitivity and 93% specificity).
  
  
  
  SpectraClassifier identified candidate biomarkers for infarct evolution (mobile lipids accumulation) and different brain regions (myoinositol content).
authors.affiliation: Stroke Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Sant Antoni Maria Claret 167, 08025, Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Jiménez-Xarrié
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Unitat de Biociències, Edifici C, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain.|Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08193, Cerdanyola del Vallès, Spain.
authors.forename: Myriam
authors.initials: M
authors.lastname: Davila
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Unitat de Biociències, Edifici C, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain.|Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08193, Cerdanyola del Vallès, Spain.|Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Candiota
authors.affiliation: Stroke Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Sant Antoni Maria Claret 167, 08025, Barcelona, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Delgado-Mederos
authors.affiliation: Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08193, Cerdanyola del Vallès, Spain.|Department of Applied Mathematics, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK.
authors.forename: Sandra
authors.initials: S
authors.lastname: Ortega-Martorell
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Unitat de Biociències, Edifici C, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain.|Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08193, Cerdanyola del Vallès, Spain.|Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain.
authors.forename: Margarida
authors.initials: M
authors.lastname: Julià-Sapé
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Unitat de Biociències, Edifici C, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain. carles.arus@uab.cat.|Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), 08193, Cerdanyola del Vallès, Spain. carles.arus@uab.cat.|Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Spain. carles.arus@uab.cat.
authors.forename: Carles
authors.initials: C
authors.lastname: Arús
authors.affiliation: Stroke Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Sant Antoni Maria Claret 167, 08025, Barcelona, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Martí-Fàbregas
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D002545:Brain Ischemia / Q000145:classification* / Q000000981:diagnostic imaging / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007294:Inositol / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D050356:Lipid Metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D055442:Metabolome; D055432:Metabolomics / Q000379:methods; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D012984:Software; D020521:Stroke / Q000145:classification* / Q000000981:diagnostic imaging / Q000378:metabolism
chemical_list: D019344:Lactic Acid; D007294:Inositol; D003401:Creatine
keywords: Animal model; Magnetic resonance spectroscopy; Metabolomics; Pattern recognition; Stroke