Contribution of Magnetic Resonance Imaging Studies to the Understanding of Cerebral Malaria Pathogenesis.

Cerebral malaria (CM), the most lethal clinical syndrome of infection, mostly affects children under 5 in sub-Saharan Africa. CM is characterized by seizures and impaired consciousness that lead to death in 15-20% of cases if treated quickly, but it is completely fatal when untreated. Brain magnetic resonance imaging (MRI) is an invaluable source of information on the pathophysiology of brain damage, but, due to limited access to scanners in endemic regions, only until very recently have case reports of CM patients studied with advanced MRI methods been published.

Repeatability of alkaline inorganic phosphate quantification in the skeletal muscle using P-magnetic resonance spectroscopy at 3 T.

The detection of a secondary inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (P-MRS), poses technical challenges at 3 Tesla (T). Overcoming these challenges is imperative for the integration of this biomarker into clinical research. To evaluate the repeatability and reliability of measuring resting skeletal muscle alkaline Pi (Pi) using with P-MRS at 3 T.

Self-assembling dendrimer nanosystems for specific fluorine magnetic resonance imaging and effective theranostic treatment of tumors.

Fluorine magnetic resonance imaging (F-MRI) is particularly promising for biomedical applications owing to the absence of fluorine in most biological systems. However, its use has been limited by the lack of safe and water-soluble imaging agents with high fluorine contents and suitable relaxation properties. We report innovative F-MRI agents based on supramolecular dendrimers self-assembled by an amphiphilic dendrimer composed of a hydrophobic alkyl chain and a hydrophilic dendron.

Neurofilament Light Chain Levels Interact with Neurodegenerative Patterns and Motor Neuron Dysfunction in Amyotrophic Lateral Sclerosis.

Background And Purpose: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease involving rapid motor neuron degeneration leading to brain, primarily precentral, atrophy. Neurofilament light chains are a robust prognostic biomarker highly specific to ALS, yet associations between neurofilament light chains and MR imaging outcomes are not well-understood. We investigated the role of neurofilament light chains as mediators among neuroradiologic assessments, precentral neurodegeneration, and disability in ALS.

Dynamic functional changes upon thalamotomy in essential tremor depend on baseline brain morphometry.

Patients with drug-resistant essential tremor (ET) may undergo Gamma Knife stereotactic radiosurgical thalamotomy (SRS-T), where the ventro-intermediate nucleus of the thalamus (Vim) is lesioned by focused beams of gamma radiations to induce clinical improvement. Here, we studied SRS-T impacts on left Vim dynamic functional connectivity (dFC, n = 23 ET patients scanned before and 1 year after intervention), and on surface-based morphometric brain features (n = 34 patients, including those from dFC analysis). In matched healthy controls (HCs), three dFC states were extracted from resting-state functional MRI data.

Mitigating slice cross-talk in multi-slice multi-echo spin echo T mapping.

Purpose: To investigate whether a T inter-slice variation could occur when a multi-slice multi-echo spin echo (MESE) sequence is used for image acquisition and to propose an enhanced method for reconstructing T maps that can effectively address and correct these variations.

Methods: Bloch simulations were performed accounting for the direct saturation effect to evaluate magnetization changes in multi-slice 2D MESE sequence. Experimental phantom scans were performed to validate these simulations.

Modular Self-Assembling Dendrimer Nanosystems for Magnetic Resonance and Multimodality Imaging of Tumors.

Bioimaging is a powerful tool for diagnosing tumors but remains limited in terms of sensitivity and specificity. Nanotechnology-based imaging probes able to accommodate abundant imaging units with different imaging modalities are particularly promising for overcoming these limitations. In addition, the nanosized imaging agents can specifically increase the contrast of tumors by exploiting the enhanced permeability and retention effect.

Autologous haematopoietic stem cell transplantation for multiple sclerosis: a position paper and registry outline.

Background: While substantial progress has been made in the development of disease-modifying medications for multiple sclerosis (MS), a high percentage of treated patients still show progression and persistent inflammatory activity. Autologous haematopoietic stem cell transplantation (AHSCT) aims at eliminating a pathogenic immune repertoire through intense short-term immunosuppression that enables subsequent regeneration of a new and healthy immune system to re-establish immune tolerance for a long period of time. A number of mostly open-label, uncontrolled studies conducted over the past 20 years collected about 4000 cases.

Quantification of muscle involvement in familial amyloid polyneuropathy using MRI.

Background And Purpose: Transthyretin familial amyloid polyneuropathy (TTR-FAP) is a rare genetic disease with autosomal-dominant inheritance. In this study, we aimed to quantify fatty infiltration (fat fraction [FF]) and magnetization transfer ratio (MTR) in individual muscles of patients with symptomatic and asymptomatic TTR-FAP using magnetic resonance imaging. Secondarily, we aimed to assess correlations with clinical and electrophysiological variables.

CNN-based fully automatic wrist cartilage volume quantification in MR images: A comparative analysis between different CNN architectures.

Purpose: Automatic measurement of wrist cartilage volume in MR images.

Methods: We assessed the performance of four manually optimized variants of the U-Net architecture, nnU-Net and Mask R-CNN frameworks for the segmentation of wrist cartilage. The results were compared to those from a patch-based convolutional neural network (CNN) we previously designed.

Radiomics model to classify mammary masses using breast DCE-MRI compared to the BI-RADS classification performance.

Background: Recent advanced in radiomics analysis could help to identify breast cancer among benign mammary masses. The aim was to create a radiomics signature using breast DCE-MRI extracted features to classify tumors and to compare the performances with the BI-RADS classification.

Material And Methods: From September 2017 to December 2019 images, exams and records from consecutive patients with mammary masses on breast DCE-MRI and available histology from one center were retrospectively reviewed (79 patients, 97 masses).

Morphometric and microstructural characteristics of hippocampal subfields in mesial temporal lobe epilepsy and their correlates with mnemonic discrimination.

Introduction: Pattern separation (PS) is a fundamental aspect of memory creation that defines the ability to transform similar memory representations into distinct ones, so they do not overlap when storing and retrieving them. Experimental evidence in animal models and the study of other human pathologies have demonstrated the role of the hippocampus in PS, in particular of the dentate gyrus (DG) and CA3. Patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HE) commonly report mnemonic deficits that have been associated with failures in PS.

Morphometric features of drug-resistant essential tremor and recovery after stereotactic radiosurgical thalamotomy.

Essential tremor (ET) is the most common movement disorder. Its neural underpinnings remain unclear. Here, we quantified structural covariance between cortical thickness (CT), surface area (SA), and mean curvature (MC) estimates in patients with ET before and 1 year after ventro-intermediate nucleus stereotactic radiosurgical thalamotomy, and contrasted the observed patterns with those from matched healthy controls.

Exploring the heterogeneous morphometric data in essential tremor with probabilistic modelling.

Essential tremor (ET) is a prevalent movement disorder characterized by marked clinical heterogeneity. Here, we explored the morphometric underpinnings of this cross-subject variability on a cohort of 34 patients with right-dominant drug-resistant ET and 29 matched healthy controls (HCs). For each brain region, group-wise morphometric data was modelled by a multivariate Gaussian to account for morphometric features' (co)variance.

Huntingtin regulates calcium fluxes in skeletal muscle.

The expression of the Huntingtin protein, well known for its involvement in the neurodegenerative Huntington's disease, has been confirmed in skeletal muscle. The impact of HTT deficiency was studied in human skeletal muscle cell lines and in a mouse model with inducible and muscle-specific HTT deletion. Characterization of calcium fluxes in the knock-out cell lines demonstrated a reduction in excitation-contraction (EC) coupling, related to an alteration in the coupling between the dihydropyridine receptor and the ryanodine receptor, and an increase in the amount of calcium stored within the sarcoplasmic reticulum, linked to the hyperactivity of store-operated calcium entry (SOCE).

Graph Theoretical Analysis of Structural Covariance Reveals the Relevance of Visuospatial and Attentional Areas in Essential Tremor Recovery After Stereotactic Radiosurgical Thalamotomy.

Essential tremor (ET) is the most common movement disorder. Its pathophysiology is only partially understood. Here, we leveraged graph theoretical analysis on structural covariance patterns quantified from morphometric estimates for cortical thickness, surface area, and mean curvature in patients with ET before and one year after (to account for delayed clinical effect) ventro-intermediate nucleus (Vim) stereotactic radiosurgical thalamotomy.

Evaluation of new MR invisible silicon carbide based dielectric pads for 7 T MRI.

Purpose: The use of dielectric pads to redistribute the radiofrequency fields is currently a popular solution for 7 T MRI practical applications, especially in brain imaging. In this work, we tackle several downsides of the previous generation of dielectric pads. This new silicon carbide recipe makes them MR invisible and greatly extends the performance lifespan.

The Role of the Human Hypothalamus in Food Intake Networks: An MRI Perspective.

Hypothalamus (HT), this small structure often perceived through the prism of neuroimaging as morphologically and functionally homogeneous, plays a key role in the primitive act of feeding. The current paper aims at reviewing the contribution of magnetic resonance imaging (MRI) in the study of the role of the HT in food intake regulation. It focuses on the different MRI techniques that have been used to describe structurally and functionally the Human HT.

Factors Associated with 90-Day Mortality in Invasively Ventilated Patients with COVID-19 in Marseille, France.

Objectives: To describe clinical characteristics and management of intensive care units (ICU) patients with laboratory-confirmed COVID-19 and to determine 90-day mortality after ICU admission and associated risk factors.

Methods: This observational retrospective study was conducted in six intensive care units (ICUs) in three university hospitals in Marseille, France. Between 10 March and 10 May 2020, all adult patients admitted in ICU with laboratory-confirmed SARS-CoV-2 and respiratory failure were eligible for inclusion.