Spinal Cord Blood Perfusion Deficit is Associated with Clinical Impairment after Spinal Cord Injury.

Spinal cord injury (SCI) results in intramedullary microvasculature disruption and blood perfusion deficit at and remote from the injury site. However, the relationship between remote vascular impairment and functional recovery remains understudied. We characterized perfusion impairment , rostral to the injury, using magnetic resonance imaging (MRI), and investigated its association with lesion extent and impairment following SCI.

Fast online spectral-spatial pulse design for subject-specific fat saturation in cervical spine and foot imaging at 1.5 T.

Objective: To compensate subject-specific field inhomogeneities and enhance fat pre-saturation with a fast online individual spectral-spatial (SPSP) single-channel pulse design.

Methods: The RF shape is calculated online using subject-specific field maps and a predefined excitation k-space trajectory. Calculation acceleration options are explored to increase clinical viability.

Investigation of perfusion impairment in degenerative cervical myelopathy beyond the site of cord compression.

The aim of this study was to determine tissue-specific blood perfusion impairment of the cervical cord above the compression site in patients with degenerative cervical myelopathy (DCM) using intravoxel incoherent motion (IVIM) imaging. A quantitative MRI protocol, including structural and IVIM imaging, was conducted in healthy controls and patients. In patients, T2-weighted scans were acquired to quantify intramedullary signal changes, the maximal canal compromise, and the maximal cord compression.

What can we gain from subpopulation universal pulses? A simulation-based study.

Purpose: The aim of the study was to explore a novel methodology for designing universal pulses (UPs) that balances the benefits of a calibration-free approach with subject-specific online pulse design.

Methods: The proposed method involves segmenting the population into subpopulations with variability in anatomical shapes and positions reduced to 75%, 50%, and 25% of their original values while keeping the mean values unchanged. An additional 25% extreme case with a large volume of interest and shifted position was included.

Contrast-agent-based perfusion MRI code repository and testing framework: ISMRM Open Science Initiative for Perfusion Imaging (OSIPI).

Purpose: Software has a substantial impact on quantitative perfusion MRI values. The lack of generally accepted implementations, code sharing and transparent testing reduces reproducibility, hindering the use of perfusion MRI in clinical trials. To address these issues, the ISMRM Open Science Initiative for Perfusion Imaging (OSIPI) aimed to establish a community-led, centralized repository for sharing open-source code for processing contrast-based perfusion imaging, incorporating an open-source testing framework.

Tau, an sensor of tau multimerization, identifies neuroprotective interventions in tauopathy.

Tau protein aggregates are a defining neuropathological feature of "tauopathies," a group of neurodegenerative disorders that include Alzheimer's disease. In the current study, we develop a split-luciferase-based sensor of tau-tau interaction. This model, which we term "tau," allows investigators to quantify tau multimerization at individual time points or longitudinally in adult, living animals housed in a 96-well plate.

Clinically compatible subject-specific dynamic parallel transmit pulse design for homogeneous fat saturation and water-excitation at 7T: Proof-of-concept for CEST MRI of the brain.

Purpose: To evaluate the benefits and challenges of dynamic parallel transmit (pTx) pulses for fat saturation (FS) and water-excitation (WE), in the context of CEST MRI.

Methods: "Universal" k -points (for FS) and spiral non-selective (for WE) trajectories were optimized offline for flip angle (FA) homogeneity. Routines to optimize the pulse shape online, based on the subject's fields maps, were implemented (target FA of 110°/0° for FS, 0°/5° for WE at fat/water frequencies).

Pulmonary Dysfunction after Pediatric COVID-19.

Background Long COVID occurs at a lower frequency in children and adolescents than in adults. Morphologic and free-breathing phase-resolved functional low-field-strength MRI may help identify persistent pulmonary manifestations after SARS-CoV-2 infection. Purpose To characterize both morphologic and functional changes of lung parenchyma at low-field-strength MRI in children and adolescents with post-COVID-19 condition compared with healthy controls.

Exploration and analysis of R-loop mapping data with RLBase.

R-loops are three-stranded nucleic acid structures formed from the hybridization of RNA and DNA. In 2012, Ginno et al. introduced the first R-loop mapping method.

Quality-controlled R-loop meta-analysis reveals the characteristics of R-loop consensus regions.

R-loops are three-stranded nucleic acid structures formed from the hybridization of RNA and DNA. While the pathological consequences of R-loops have been well-studied to date, the locations, classes, and dynamics of physiological R-loops remain poorly understood. R-loop mapping studies provide insight into R-loop dynamics, but their findings are challenging to generalize.

Free-Breathing Low-Field MRI of the Lungs Detects Functional Alterations Associated With Persistent Symptoms After COVID-19 Infection.

Objectives: With the COVID-19 pandemic, repetitive lung examinations have become necessary to follow-up symptoms and associated alterations. Low-field MRI, benefiting from reduced susceptibility effects, is a promising alternative for lung imaging to limit radiations absorbed by patients during CT examinations, which also have limited capability to assess functional alterations. The aim of this investigative study was to explore the functional abnormalities that free-breathing 0.

[Imaging of the lung using low-field magnetic resonance imaging].

Background: Lung magnetic resonance imaging (MRI) examinations are challenging and have not become established in the routine clinical setting. Recent developments in low-field MRI, combined with computer-assisted algorithms for acquisition and evaluation, promise new perspectives for imaging of pulmonary diseases.

Objectives: This review aims to inform about the physical advantages of low-field MRI for imaging the lungs, provide a review of the sparse literature, and present first results from a new low-field MRI scanner.

Tau-induced deficits in nonsense-mediated mRNA decay contribute to neurodegeneration.

Introduction: While brains of patients with Alzheimer's disease and related tauopathies have evidence of altered RNA processing, we lack a mechanistic understanding of how altered RNA processing arises in these disorders and if such changes are causally linked to neurodegeneration.

Methods: Using Drosophila melanogaster models of tauopathy, we find that overall activity of nonsense-mediated mRNA decay (NMD), a key RNA quality-control mechanism, is reduced. Genetic manipulation of NMD machinery significantly modifies tau-induced neurotoxicity, suggesting that deficits in NMD are causally linked to neurodegeneration.

Biomechanical comparison of spinal cord compression types occurring in Degenerative Cervical Myelopathy.

Background: Degenerative Cervical Myelopathy results from spine degenerations narrowing the spinal canal and inducing cord compressions. Prognosis is challenging. This study aimed at simulating typical spinal cord compressions observed in patients with a realistic model to better understand pathogenesis for later prediction of patients' evolution.

Feasibility of human spinal cord perfusion mapping using dynamic susceptibility contrast imaging at 7T: Preliminary results and identified guidelines.

Purpose: To explore the feasibility of dynamic susceptibility contrast MRI at 7 Tesla for human spinal cord perfusion mapping and fill the gap between brain and spinal cord perfusion mapping techniques.

Methods: Acquisition protocols for high-resolution single shot EPI in the spinal cord were optimized for both spin-echo and gradient-echo preparations, including cardiac gating, acquisition times and breathing cycle recording. Breathing-induced MRI signal fluctuations were investigated in healthy volunteers.

Robustness Through Simplicity: A Minimalist Gateway to Neurorobotic Flight.

In attempting to build neurorobotic systems based on flying animals, engineers have come to rely on existing firmware and simulation tools designed for miniature aerial vehicles (MAVs). Although they provide a valuable platform for the collection of data for Deep Learning and related AI approaches, such tools are deliberately designed to be general (supporting air, ground, and water vehicles) and feature-rich. The sheer amount of code required to support such broad capabilities can make it a daunting task to adapt these tools to building neurorobotic systems for flight.

Intravoxel Incoherent Motion at 7 Tesla to quantify human spinal cord perfusion: limitations and promises.

Purpose: To develop a noninvasive technique to map human spinal cord (SC) perfusion in vivo. More specifically, to implement an intravoxel incoherent motion (IVIM) protocol at ultrahigh field for the human SC and assess parameters estimation errors.

Methods: Monte-Carlo simulations were conducted to assess estimation errors of 2 standard IVIM fitting approaches (two-step versus one-step fit) over the range of IVIM values reported for the human brain and for typical SC diffusivities.

Mitochondrial clearance and maturation of autophagosomes are compromised in LRRK2 G2019S familial Parkinson's disease patient fibroblasts.

This study utilized human fibroblasts as a preclinical discovery and diagnostic platform for identification of cell biological signatures specific for the LRRK2 G2019S mutation producing Parkinson's disease (PD). Using live cell imaging with a pH-sensitive Rosella biosensor probe reflecting lysosomal breakdown of mitochondria, mitophagy rates were found to be decreased in fibroblasts carrying the LRRK2 G2019S mutation compared to cells isolated from healthy subject (HS) controls. The mutant LRRK2 increased kinase activity was reduced by pharmacological inhibition and targeted antisense oligonucleotide treatment, which normalized mitophagy rates in the G2019S cells and also increased mitophagy levels in HS cells.

Neurite Collapse and Altered ER Ca Control in Human Parkinson Disease Patient iPSC-Derived Neurons with LRRK2 G2019S Mutation.

The Parkinson disease (PD) genetic LRRK2 gain-of-function mutations may relate to the ER pathological changes seen in PD patients at postmortem. Human induced pluripotent stem cell (iPSC)-derived neurons with the PD pathogenic LRRK2 G2019S mutation exhibited neurite collapse when challenged with the ER Ca influx sarco/ER Ca-ATPase inhibitor thapsigargin (THP). Baseline ER Ca levels measured with the ER Ca indicator CEPIA-ER were lower in LRRK2 G2019S human neurons, including in differentiated midbrain dopamine neurons in vitro.

Tau-induced nuclear envelope invagination causes a toxic accumulation of mRNA in Drosophila.

The nucleus is a spherical dual-membrane bound organelle that encapsulates genomic DNA. In eukaryotes, messenger RNAs (mRNA) are transcribed in the nucleus and transported through nuclear pores into the cytoplasm for translation into protein. In certain cell types and pathological conditions, nuclei harbor tubular invaginations of the nuclear envelope known as the "nucleoplasmic reticulum.

Correction: Test-retest reliability of myelin imaging in the human spinal cord: Measurement errors versus region- and aging-induced variations.

[This corrects the article DOI: 10.1371/journal.pone.

Test-retest reliability of myelin imaging in the human spinal cord: Measurement errors versus region- and aging-induced variations.

Purpose: To implement a statistical framework for assessing the precision of several quantitative MRI metrics sensitive to myelin in the human spinal cord: T1, Magnetization Transfer Ratio (MTR), saturation imposed by an off-resonance pulse (MTsat) and Macromolecular Tissue Volume (MTV).

Methods: Thirty-three healthy subjects within two age groups (young, elderly) were scanned at 3T. Among them, 16 underwent the protocol twice to assess repeatability.

Nicotine as a discriminative stimulus for ethanol use.

Abused drugs reinforce behavior; i.e., they increase the probability of the behavior preceding their administration.

SCT: Spinal Cord Toolbox, an open-source software for processing spinal cord MRI data.

For the past 25 years, the field of neuroimaging has witnessed the development of several software packages for processing multi-parametric magnetic resonance imaging (mpMRI) to study the brain. These software packages are now routinely used by researchers and clinicians, and have contributed to important breakthroughs for the understanding of brain anatomy and function. However, no software package exists to process mpMRI data of the spinal cord.

ZOOM or Non-ZOOM? Assessing Spinal Cord Diffusion Tensor Imaging Protocols for Multi-Centre Studies.

The purpose of this study was to develop and evaluate two spinal cord (SC) diffusion tensor imaging (DTI) protocols, implemented at multiple sites (using scanners from two different manufacturers), one available on any clinical scanner, and one using more advanced options currently available in the research setting, and to use an automated processing method for unbiased quantification. DTI parameters are sensitive to changes in the diseased SC. However, imaging the cord can be technically challenging due to various factors including its small size, patient-related and physiological motion, and field inhomogeneities.