Couplage de mesures sur site et de méthodes géostatistiques : mise en oeuvre " en temps réel " à l'aide d'un FPXRF Projet REPERAGE

National audienceLa caractérisation des sites pollués effectuée à l'aide de prélèvements de sol et d'analyses de laboratoire est une étape longue et coûteuse. De telles pratiques incitent à limiter le nombre de points de mesure et ne permettent pas facilement, dans une même campagne, d'utiliser les premiers résultats d'analyse pour ajuster la localisation de nouveaux points d'échantillonnage. Depuis plusieurs années sont apparus sur le marché de nouveaux appareils portatifs permettant d'analyser sur le terrain la teneur en polluants dans les sols en un temps très court. Parmi ceux-ci les spectromètres portables à fluorescence de rayons X (FPXRF) sont de plus en plus utilisés pour analyser les métaux. Dans le même temps, des approches géostatistiques adaptées aux particularités des sites et sols pollués ont été développées en Europe et sont de plus en plus utilisées pour cartographier les sols en fonction de seuils réglementaires ou estimer des quantités de matériaux contaminés, tout en en quantifiant les incertitudes locales ou globales associées. Le couplage des deux outils, mesures sur site et méthodes géostatistiques, permet d'envisager des campagnes de reconnaissance optimisées où le nombre et la localisation de nouveaux points de mesure sont déterminés au fur et à mesure de l'acquisition des données dans l'objectif de réduire l'incertitude affectant la modélisation de la contamination. Le projet de recherche REPERAGE vise à concevoir une démarche associant mesures sur site et traitement géostatistique pour conduire de façon rationnelle des campagnes de reconnaissance par rapport à des scénarios et des objectifs classiques de gestion de sites contaminés (par ex. classification des sols par rapport à des seuils, estimation de tonnages, estimation de coûts de dépollution). Le travail réalisé inclut le développement théorique de la démarche et d'un code permettant de la mettre en oeuvre, la validation de la démarche à partir des données d'un site réel bien renseigné, les environs de l'ancienne usine MétalEurop (Nord de la France), et sa mise en oeuvre " en temps réel " sur le site d'une ancienne usine sidérurgique (Henricot II, Belgique). La communication aura pour objet de présenter les principaux résultats obtenus dans le cadre de ce projet

Robust Bayesian fusion of continuous segmentation maps

International audienceThe fusion of probability maps is required when trying to analyse a collection of image labels or probability maps produced by several segmentation algorithms or human raters. The challenge is to weight the combination of maps correctly, in order to reflect the agreement among raters, the presence of outliers and the spatial uncertainty in the consensus. In this paper, we address several shortcomings of prior work in continuous label fusion. We introduce a novel approach to jointly estimate a reliable consensus map and to assess the presence of outliers and the confidence in each rater. Our robust approach is based on heavy-tailed distributions allowing local estimates of raters performances. In particular, we investigate the Laplace, the Student’s t and the generalized double Pareto distributions, and compare them with respect to the classical Gaussian likelihood used in prior works. We unify these distributions into a common tractable inference scheme based on variational calculus and scale mixture representations. Moreover, the introduction of bias and spatial priors leads to proper rater bias estimates and control over the smoothness of the consensus map. Finally, we propose an approach that clusters raters based on variational boosting, and thus may produce several alternative consensus maps. Our approach was successfully tested on MR prostate delineations and on lung nodule segmentations from the LIDC-IDRI dataset

Personalized dietary advices provided by a dietitian increase calcium intake in outpatients with multiple sclerosis—Results from a randomized, controlled, single-blind trial

Background and aimsMultiple sclerosis (MS) is associated with osteoporosis, possibly due to neurological disability and decreased calcium intake. The objective of this study was to evaluate the efficacy of a personalized nutritional advice program by a dietitian compared to the delivery of a standard advice form to optimize dietary calcium intake in outpatients with MS.MethodsWe performed a randomized, controlled, parallel trial comparing the efficacy of a personalized dietary advice (PDA) program to standard advice form (SAF) to increase daily calcium intake in MS patients. The study population was composed by patients with relapsing-remitting MS aged 18–69 years old. PDA program consisted in dietary advice delivered by a dietitian at baseline, 1 month, and 3 months. Calcium and nutrient intake in patients from both groups was evaluated at baseline and 6 months using a dietary survey.ResultsOf the 194 patients screened for inclusion, 182 patients were included (79% female, median age of 42 years, and median EDSS of 2.0), and randomized to SAF (n = 92) or PDA (n = 90). At 6 months, median calcium intake increased by 241 mg/day in the PDA group and decreased by 120 mg/day in the SAF group (p < 0.0001). However, the median calcium intake was 947 mg/day in the SAF group and 778 mg/day in the PDA group at baseline (p = 0.0077), potentially favoring the effect of dietary advice. Complementary analyses focusing on patients with insufficient calcium intakes at baseline revealed comparable values in both groups (p = 0.69). Of those, patients included in the PDA group obtained significantly higher calcium intakes at 6 months than patients from the SAF group (p = 0.0086) independently of EDSS, PASAT, HADS and EQ-5D scores.ConclusionThis work shows the efficacy of dietary management based on personalized advice program over 3 months to durably increase calcium consumption in MS patients with insufficient calcium intake.Clinical trial registrationclinicaltrials.gov, identifier NCT02664623

A MANBA mutation resulting in residual beta-mannosidase activity associated with severe leukoencephalopathy: a possible pseudodeficiency variant

<p>Abstract</p> <p>Background</p> <p>β-Mannosidosis (OMIM 248510) is a rare inborn lysosomal storage disorder caused by the deficient activity of β-mannosidase, an enzyme encoded by a single gene (<it>MANBA</it>) located on chromosome 4q22-25. To date, only 20 cases of this autosomal recessive disorder have been described and 14 different <it>MANBA </it>mutations were incriminated in the disease. These are all null mutations or missense mutations that abolish β-mannosidase activity. In this study, we characterized the molecular defect of a new case of β-mannosidosis, presenting with a severe neurological disorder.</p> <p>Methods</p> <p>Genomic DNA was isolated from peripheral blood leukocytes of the patient to allow <it>MANBA </it>sequencing. The identified mutation was engineered by site-directed mutagenesis and the mutant protein was expressed through transient transfection in HEK293T cells. The β-mannosidase expression and activity were respectively assessed by Western blot and fluorometric assay in both leukocytes and HEK293T cells.</p> <p>Results</p> <p>A missense disease-associated mutation, c.1922G>A (p.Arg641His), was identified for which the patient was homozygous. In contrast to previously described missense mutations, this substitution does not totally abrogate the enzyme activity but led to a residual activity of about 7% in the patient's leukocytes, 11% in lymphoblasts and 14% in plasma. Expression studies in transfected cells also resulted in 7% residual activity.</p> <p>Conclusion</p> <p>Correlations between MANBA mutations, residual activity of β-mannosidase and the severity of the ensuing neurological disorder are discussed. Whether the c.1922G>A mutation is responsible for a yet undescribed pseudodeficiency of β-mannosidase is also discussed.</p

Long-term outcomes of CLIPPERS (chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids) in a consecutive series of 12 patients.

BACKGROUND: Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a central nervous system inflammatory disease. OBJECTIVE: To describe the disease course of CLIPPERS. DESIGN: A nationwide study was implemented to collect clinical, magnetic resonance imaging, cerebrospinal fluid, and brain biopsy specimen characteristics of patients with CLIPPERS. SETTING: Academic research. PATIENTS: Twelve patients with CLIPPERS. MAIN OUTCOME MEASURES: The therapeutic management of CLIPPERS was evaluated. RESULTS: Among 12 patients, 42 relapses were analyzed. Relapses lasted a mean duration of 2.5 months, manifested frequent cerebellar ataxia and diplopia, and were associated with a mean Expanded Disability Status Scale (EDSS) score of 4. Besides typical findings of CLIPPERS, magnetic resonance imaging showed brainstem mass effect in 5 patients, extensive myelitis in 3 patients, and closed ring enhancement in 1 patient. Inconstant oligoclonal bands were found on cerebrospinal fluid investigation in 4 patients, with an increased T-cell ratio of CD4 to CD8. Among 7 available brain biopsy specimens, staining was positive for perivascular CD4 T lymphocytes in 5 samples. Thirty-eight of 42 relapses were treated with pulse corticosteroid therapy, which led to improvement, with a mean residual EDSS score of 1.9 (range, 0-7). In 1 patient with untreated relapses, scores on the EDSS progressively increased to a score of 10 at death. Among 5 patients without long-term corticosteroid therapy, the mean annualized relapse rate was 0.5 (range, 0.25-2.8). Among 7 patients taking oral corticosteroids, no relapses occurred in those whose daily dose was 20 mg or higher. No progressive course of CLIPPERS was observed. Four patients with a final EDSS score of 4 or higher had experienced previous severe relapses (EDSS score, ≥5) and brainstem and spinal cord atrophy. CONCLUSIONS: CLIPPERS is a relapsing-remitting disorder without progressive forms. Long-term disability is correlated with the severity of previous relapses. Further studies are needed to confirm that prolonged corticosteroid therapy prevents further relapses.journal article2012 Julimporte

Functional outcomes in symptomatic versus asymptomatic patients undergoing incisional hernia repair: Replacing one problem with another? A prospective cohort study in 1312 patients

Background: Incisional hernias can be associated with pain or discomfort. Surgical repair especially mesh reinforcement, may likewise induce pain. The primary objective was to assess the incidence of pain after hernia repair in patients with and without pre-operative pain or discomfort. The secondary objectives were to determine the preferred mesh type, mesh location and surgical technique in minimizing postoperative pain or discomfort. Materials and methods: A registry-based prospective cohort study was performed, including patients undergoing incisional hernia repair between September 2011 and May 2019. Patients with a minimum follow-up of 3–6 months were included. The incidence of hernia related pain and discomfort was recorded perioperatively. Results: A total of 1312 patients were included. Pre-operatively, 1091 (83%) patients reported pain or discomfort. After hernia repair, 961 (73%) patients did not report pain or discomfort (mean follow-up = 11.1 months). Of the pre-operative asymptomatic patients (n = 221), 44 (20%, moderate or severe pain: n = 14, 32%) reported pain or discomfort after mean follow-up of 10.5 months. Of those patients initially reporting pain or discomfort (n = 1091), 307 (28%, moderate or severe pain: n = 80, 26%) still reported pain or discomfort after a mean follow-up of 11.3 months postoperatively. Conclusion: In symptomatic incisional hernia patients, hernia related complaints may be resolved in the majority of cases undergoing surgical repair. In asymptomatic incisional hernia patients, pain or discomfort may be induced in a considerable number of patients due to surgical repair and one should be aware if this postoperative complication

Lower limb muscle atrophy on MRI as a guide in the diagnosis of muscle diseases

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Evolution of Subarachnoid Hemorrhage Extension in Lobar Hemorrhage in the Early Chronic Phase and the Impact on Cerebral Amyloid Angiopathy Criteria

International audienceBACKGROUND:Subarachnoid hemorrhage extension (SAHE) in acute lobar hemorrhage (LH) is frequent. Little is known about the short- and medium-term radiological evolution of SAHE. Our aim was to study this evolution by magnetic resonance imaging (MRI).METHODS:We performed an observational study and analyzed retrospectively MRIs of patients with LH with possible/probable/definite cerebral amyloid angiopathy (CAA), and compared initial MRI performed between 3 hours and 21 days after symptom onset with follow-up MRI performed between 2 and 12 months after initial MRI.RESULTS:Twenty patients were analyzed. Initial MRI showed 11 of 20 patients (55%) with SAHE. Follow-up MRI showed, compared with initial MRI, an increase of 77% (45% versus 80%) of patients with chronic intrasulcal hemorrhage, an increase of 36% (22% versus 30%) of the number of lobes with chronic intrasulcal hemorrhage, and an increase of 37% (1.75 versus 2.4) of lobes with chronic intrasulcal hemorrhage seen per patient. All new chronic intrasulcal hemorrhages involved the brain lobe with initial LH except 1 lobe in 1 patient. Three patients switched from possible to probable CAA according to the modified Boston criteria after follow-up MRI due to chronic intrasulcal hemorrhage in the lobe involved by LH. In 6 patients, follow-up MRI showed more diffuse chronic intrasulcal hemorrhage than pre-existing combined SAHE and chronic intrasulcal hemorrhage in the LH lobe, or showed presence of chronic intrasulcal hemorrhage in the absence of initial SAHE and/or chronic intrasulcal hemorrhage in the LH lobe.CONCLUSION:In LH patients, presence of SAHE on initial MRI changes the modified Boston CAA criteria on follow-up MRI in a portion of patients. On follow-up MRI, SAHE/chronic intrasulcal hemorrhage extension or chronic intrasulcal hemorrhage appearance in the LH lobe is relatively frequent

CSF RBC count in successful first-attempt lumbar puncture: the interest of atraumatic needle use

International audienceThe objective of this study is to analyze CSF red blood cell (RBC) count from first-attempt lumbar punctures and to analyze parameters associated with first-attempt lumbar punctures and hemorrhagic lumbar puncture. This is a prospective analysis of consecutive patients who underwent lumbar puncture for any reason other than suspected acute subarachnoid hemorrhage. Analyzed parameters were the following: age, indication for lumbar puncture, aPTT ratio, PTT, platelet count, patient's position, needle type (atraumatic/standard), needle diameter, person performing lumbar puncture (medical student/resident/attending physician), number of lumbar levels punctured, necessity of needle repositioning, CSF RBC and white blood cell count, and protein level. Lumbar puncture resulting in RBC count > 5 RBC/mm2 was classified as hemorrhagic lumbar puncture (different cut-offs were studied: > 5/> 10/> 100/> 500/> 1000 RBC). In total, 169 elective lumbar punctures in 165 different patients were included. First-attempt lumbar puncture occurred in 22% > 5 RBC, in 19.5% > 10 RBC, in 4.5% > 100 RBC, in 3% > 500 RBC, and 1.5% > 1000 RBC count. First-attempt lumbar puncture was associated with non-hemorrhagic lumbar puncture for each of the RBC count cut-offs (OR for non-hemorrhagic lumbar puncture in first-attempt lumbar puncture 2.8, 95% CI 1.4-5.7). The presence of a hemorrhagic disorder (concerning cerebral amyloid angiopathy in all patients) and higher aPTT ratio were associated with hemorrhagic lumbar puncture. Atraumatic needle use was associated with non-hemorrhagic lumbar puncture for RBC count cut-offs ≤ 5 and ≤ 10 RBC (OR for non-hemorrhagic lumbar puncture in atraumatic needle use 2.5 [95% CI 1.3-4.8] and 2.2 [95% CI 1.1-4.4], respectively). First-attempt lumbar puncture and hemorrhagic lumbar puncture were not associated with other parameters. Slightly elevated CSF RBC count after first-attempt lumbar puncture occurs relatively frequently, but is even more frequent in non-first-attempt lumbar puncture. Atraumatic needle use is associated with non-hemorrhagic lumbar puncture

Radiologically Isolated Cerebral Amyloid Angiopathy-Related Inflammation

International audienceIn amyloid β-related angiitis of the central nervous system (also called cerebral amyloid angiopathy-related inflammation), cerebral amyloid angiopathy occurs in association with primary vasculitis of small- and medium-sized leptomeningeal and cortical arteries. To avoid brain biopsy, clinicoradiological criteria (including clinical features due to inflammation-related uni/multifocal white matter hyperintensities) for the diagnosis of cerebral amyloid angiopathy-related inflammation have been validated recently. We report 3 cases with acute symptoms directly related to cerebral amyloid angiopathy in the presence of asymptomatic cerebral amyloid angiopathy-related inflammation hyperintensities on initial magnetic resonance imaging. Recognizing radiological features of cerebral amyloid angiopathy-related inflammation in patients with cerebral amyloid angiopathy is important because radiological isolated cerebral amyloid angiopathy-related inflammation may become symptomatic and immunosuppressive treatment is often effective in cerebral amyloid angiopathy-related inflammation, although optimal treatment regimen is yet unknown. In contrast, apart from hypertension treatment, few therapeutic options exist in cerebral amyloid angiopathy