Barcelona, Spain
Barcelona, Spain

Time filter

Source Type

PubMed | University of Trento, University of Genoa, University of Barcelona, LENITEM Laboratory of Epidemiology and 15 more.
Type: Journal Article | Journal: Human brain mapping | Year: 2016

Free water elimination (FWE) in brain diffusion MRI has been shown to improve tissue specificity in human white matter characterization both in health and in disease. Relative to the classical diffusion tensor imaging (DTI) model, FWE is also expected to increase sensitivity to microstructural changes in longitudinal studies. However, it is not clear if these two models differ in their test-retest reproducibility. This study compares a bi-tensor model for FWE with DTI by extending a previous longitudinal-reproducibility 3T multisite study (10 sites, 7 different scanner models) of 50 healthy elderly participants (55-80 years old) scanned in two sessions at least 1 week apart. We computed the reproducibility of commonly used DTI metrics (FA: fractional anisotropy, MD: mean diffusivity, RD: radial diffusivity, and AXD: axial diffusivity), derived either using a DTI model or a FWE model. The DTI metrics were evaluated over 48 white-matter regions of the JHU-ICBM-DTI-81 white-matter labels atlas, and reproducibility errors were assessed. We found that relative to the DTI model, FWE significantly reduced reproducibility errors in most areas tested. In particular, for the FA and MD metrics, there was an average reduction of approximately 1% in the reproducibility error. The reproducibility scores did not significantly differ across sites. This study shows that FWE improves sensitivity and is thus promising for clinical applications, with the potential to identify more subtle changes. The increased reproducibility allows for smaller sample size or shorter trials in studies evaluating biomarkers of disease progression or treatment effects. Hum Brain Mapp 38:12-26, 2017. 2016 Wiley Periodicals, Inc.

PubMed | University of Trento, University of Genoa, University of Barcelona, University of Leipzig and 16 more.
Type: Journal Article | Journal: Human brain mapping | Year: 2016

Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within-site test-retest reliability and the across-site reproducibility consistency of DMN-derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue-based regression, PESTICA and FSL-FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z-scores and, albeit less markedly, the cluster-size in the DMN; in particular, FSL-FIX tended to increase the DMN z-scores compared to others. Within-site test-retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5-11% for DMN z-scores and cluster-size reliability. DMN pattern overlap was in the range 60-65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL-FIX and Tissue-based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC=0.67) for the DMN z-scores relative to NPC. Overall these findings support the use of rPNC methods like tissue-based or FSL-FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114-2132, 2016. 2016 Wiley Periodicals, Inc.

Madrigal I.,CIBER ISCIII | Madrigal I.,Hospital Clinic and IDIBAPS | Rodriguez-Revenga L.,CIBER ISCIII | Rodriguez-Revenga L.,Hospital Clinic and IDIBAPS | And 3 more authors.
Gene | Year: 2012

Genomic rearrangements of chromosome 15q11-q13 are responsible for diverse phenotypes including intellectual disabilities and autism. 15q11.2 deletion, implicating common PWS/AS breakpoints BP1-BP2, has been described in patients with delayed motor and speech development and behavioural problems. Here we report the clinical and molecular characterisation of a maternally inherited BP1-BP2 deletion in two siblings with intellectual, motor and speech delay, autistic syndrome disorder and several dysmorphic features. One of the patients was also a carrier of an FMR1 allele in the low premutation range. The four genes within the deletion were under-expressed in all deletion carriers but FMR1 mRNA levels remained normal. Our results suggest that BP1-BP2 deletion could be considered as a risk factor for neuropsychological phenotypes and that it presents with variable clinical expressivity. © 2012 Elsevier B.V.

Madrigal I.,CIBER ISCIII | Madrigal I.,Hospital Clinic and IDIBAPS | Martinez M.,Hospital Universitario Virgen Of Las Nieves | Rodriguez-Revenga L.,CIBER ISCIII | And 4 more authors.
American Journal of Medical Genetics, Part A | Year: 2012

Congenital balanced reciprocal translocations are one of the most frequent structural chromosomal aberrations in the population. We report a familial translocation t(12;22)(p13.3;pter) responsible for intellectual disabilities and congenital anomalies characterized by FISH and array CGH. Two patients carried a der(12)t(12;22)(p13.3;pter), resulting in a 6Mb 12pter deletion. Patients presented with intellectual disabilities, pre- and post-natal growth retardation, ponderal development delay, global hypotonia, feeding problems and dysmorphic features. Two relatives presented with the reciprocal 12pter duplication, which had no clinical manifestations associated. For this translocation, we propose a mechanism based on a non-allelic recombination model, in which recombination of direct oriented segmental duplications between non-homologous chromatids leads to the reciprocal translocation. The characterization of this translocation has been critical for the family. Translocation carriers have a risk of 40% of having offspring carrying unbalanced products. 12p13.3 deletion carriers present with a recognizable syndrome and on the contrary, 12p13.3 duplication carriers present without clinical manifestations. Other published cases of 12p13.3 duplication show that this syndrome has a variable phenotype. It is advisable to delineate the duplication size and to discard other genetic aberrations, in order to give an accurate genetic counseling in patients carrying 12pter duplications. © 2012 Wiley Periodicals, Inc.

PubMed | EULAR, Diakonhjemmet Hospital, St Vincents University Hospital, North Devon and 22 more.
Type: Journal Article | Journal: Annals of the rheumatic diseases | Year: 2016

Since the publication of the European League Against Rheumatism recommendations for the pharmacological treatment of psoriatic arthritis (PsA) in 2012, new evidence and new therapeutic agents have emerged. The objective was to update these recommendations.A systematic literature review was performed regarding pharmacological treatment in PsA. Subsequently, recommendations were formulated based on the evidence and the expert opinion of the 34 Task Force members. Levels of evidence and strengths of recommendations were allocated.The updated recommendations comprise 5 overarching principles and 10 recommendations, covering pharmacological therapies for PsA from non-steroidal anti-inflammatory drugs (NSAIDs), to conventional synthetic (csDMARD) and biological (bDMARD) disease-modifying antirheumatic drugs, whatever their mode of action, taking articular and extra-articular manifestations of PsA into account, but focusing on musculoskeletal involvement. The overarching principles address the need for shared decision-making and treatment objectives. The recommendations address csDMARDs as an initial therapy after failure of NSAIDs and local therapy for active disease, followed, if necessary, by a bDMARD or a targeted synthetic DMARD (tsDMARD). The first bDMARD would usually be a tumour necrosis factor (TNF) inhibitor. bDMARDs targeting interleukin (IL)12/23 (ustekinumab) or IL-17 pathways (secukinumab) may be used in patients for whom TNF inhibitors are inappropriate and a tsDMARD such as a phosphodiesterase 4-inhibitor (apremilast) if bDMARDs are inappropriate. If the first bDMARD strategy fails, any other bDMARD or tsDMARD may be used.These recommendations provide stakeholders with an updated consensus on the pharmacological treatment of PsA and strategies to reach optimal outcomes in PsA, based on a combination of evidence and expert opinion.

PubMed | University Hospitals Leuven, Carol Davila University of Medicine and Pharmacy, Diakonhjemmet Hospital, Paris-Sorbonne University and 11 more.
Type: | Journal: Arthritis care & research | Year: 2016

Patient-physician discordance in global assessment of disease activity concerned one third of patients but what does it reflect? We aimed to assess patient-physician discordance in psoriatic arthritis (PsA) and patient-reported domains of health (physical and psychological) associated to discordance.The PsAID (Psoriatic Arthritis Impact of Disease) cross-sectional multicenter European study of patients with PsA according to expert opinion was analysed. Patient- and Physician-Global Assessment (PGA and PhGA) were rated with a 0-10 numeric rating scale. Discordance was defined as the difference (PGA-PhGA) and as the absolute difference |PGA-PhGA|3 points. Determinants of (PGA-PhGA) were assessed by a stepwise multivariate linear regression among 12 physical and psychological aspects of impact: pain, skin problems, fatigue, ability to work/leisure, functional incapacity, feeling of discomfort, sleep disturbance, anxiety/fear, coping, embarrassment/shame, social participation and depressive affects.In 460 patients (mean age 50.612.9 years, 52.2% female, mean disease duration 9.59.5 years, mean DAPSA 30.832.4, 40.4% treating by biologics), mean PGA was higher than mean PhGA with a mean absolute difference of 1.91.8 points. Discordance defined by |PGA-PhGA|3/10 concerned 134 (29.1%) patients and 115 (85.8% of patients with discordance) had PGA>PhGA. Higher fatigue (=0.14), lower self-perceived coping (=0.23) and impaired social participation (=0.16) were independently associated with a higher difference (PGA-PhGA).Discordance concerned 29.1% of these patient/physician dyads, mainly by PGA>PhGA. Factors associated with discordance were psychological rather than physical domains of health. Discordance was more frequent in patients in remission, indicating more work is needed on the patient perspective regarding disease activity. This article is protected by copyright. All rights reserved.

PubMed | Medical & Scientific Relations, University of Edinburgh, University Pompeu Fabra, Alzheimer Europe and 9 more.
Type: Journal Article | Journal: Alzheimer's & dementia : the journal of the Alzheimer's Association | Year: 2016

Alzheimers disease (AD) is among the most significant health care burdens. Disappointing results from clinical trials in late-stage AD persons combined with hopeful results from trials in persons with early-stage suggest that research in the preclinical stage of AD is necessary to define an optimal therapeutic success window. We review the justification for conducting trials in the preclinical stage and highlight novel ethical challenges that arise and are related to determining appropriate risk-benefit ratios and disclosing individuals biomarker status. We propose that to conduct clinical trials with these participants, we need to improve public understanding of AD using unified vocabulary, resolve the acceptable risk-benefit ratio in asymptomatic participants, and disclose or not biomarker status with attention to study type (observational studies vs clinical trials). Overcoming these challenges will justify clinical trials in preclinical AD at the societal level and aid to the development of societal and legal support for trial participants.

Loading Hospital Clinic and IDIBAPS collaborators
Loading Hospital Clinic and IDIBAPS collaborators