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Bile acid profile and white matter microstructural changes in early Alzheimer's disease.

BACKGROUND: Although recent disease-modifying treatments such as Lecanemab have shown promise in reducing amyloid burden and modestly slowin … us three predefined BA ratios, cerebrospinal-fluid biomarkers, and diffusion-tensor MRI. Fractional anisotropy (FA), mean (MD), radial (RD) and axial (AxD) diffusivities were derived using tract-based spatial statistics and atlas-based regions of interest. RESULTS: Higher FA was associated with greater taurochenodeoxycholic acid, L-aspartate and L-asparagin …

Exploratory MIA study: multimodal magnetic resonance imaging characteristics of rat offspring induced by maternal Poly(I:C) exposure during pregnancy.

BACKGROUND: Maternal infection or inflammatory stimulation during pregnancy can disrupt fetal brain development through immune activation, i … d MRS. Voxel-based morphometry of T2 images evaluated structural changes; DTI quantified fractional anisotropy (FA) and diffusivity indices (mean diffusivity [MD], axial diffusivity [AD], radial diffusivity [RD]); ASL measured cerebral blood flow (CBF) in the prefrontal cortex and striatum; and MRS assessed metabolite levels in the prefrontal cortex. Group d …

Correlation between anxiety-depression disorders and brain structural connectivity abnormalities after subarachnoid hemorrhage.

BACKGROUND: Subarachnoid hemorrhage (SAH) is associated with high incidence of anxiety and depression disorders (27%-54% and 20%-42%, respec … d at multiple time points (1 hour to 72 hours post-hemorrhage). DTI parameters including fractional anisotropy (FA) and apparent diffusion coefficient were measured in limbic-prefrontal circuits. Serum and cerebrospinal fluid inflammatory markers [interleukin-6 (IL-6), IL-1β, tumor necrosis factor-α] were quantified using enzyme-linked immunosorbent assay. …

The cognitive cerebellum: linking microstructure to cognitive functions in a healthy population.

BACKGROUND: The cerebellum is recognized for its role in motor control. However, it also plays a crucial part in modulating circuits involve … on grey matter (GM) and white matter (WM) volumes, while microstructural evaluation used fractional anisotropy (FA) values. METHODS: Using a large normative cohort, the study examined cerebellar GM and WM volumes in 151 participants and FA in 83 participants. Cerebellar GM and WM volumes and FA values were correlated voxel-wise against the following cogniti …

Analysis of the BOLD signal along colour-opponent pathways in LGN and V1 and microstructural alterations of the optic radiation in POAG and OHT patients.

PURPOSE: Primary open angle glaucoma (POAG) is associated with retinal ganglion cell loss and atrophies in the lateral geniculate nucleus (L … ased Spatial Statistics (TBSS) was applied to Diffusion weighted images (DWI) to compare fractional anisotropy (FA) values across the whole-brain between patient groups. Probabilistic tractography along the optic radiation (OR) tested for differences in microstructural alterations associated with POAG compared to OHT patients. Behavioural deficits associated …

The Histological and Mechanical Behavior of Skin During Puncture for Different Impactor Sizes and Loading Rates.

PURPOSE: The hierarchical structure of skin dictates its protective function against mechanical loading, which has been extensively studied through numerous experiments. Viscoelasticity and anisotropy have been defined for skin in tensile loading, but most puncture studies utilized skin simulants, which lacked natural tension and varying skin thicknesses. The purpose of this study was to define the mechanical behavior and failure thresholds of skin during puncture with various blunt impactor sizes and loading rates. METHODS: After determining natural tension of porcine skin, 232 isolated skin…

Longitudinal and transverse muscle stiffness change differently with knee osteoarthritis and do not align with stiffness sensation.

Knee osteoarthritis (OA) is a prevalent joint condition associated with disability, pain, and stiffness in the muscles surrounding the knee. Myofascial and massage techniques are employed to alleviate these symptoms. Unclear is whether muscle stiffness is measurably increased in the painful muscles, and how measured muscle stiffness relates to perceived stiffness, pain, and functional impairment. Given muscle anisotropy, stiffness changes may occur in the longitudinal plane parallel to muscle fibers or perpendicularly in the transverse plane. Shear wave velocity (SWV) was measured in both scan…

Frontotemporal dementia characterization using neurite orientation dispersion and density imaging.

Microstructural alterations in brain tissue play a crucial role in the pathophysiology of frontotemporal dementia (FTD). This study assessed … ), 14 nonfluent-variant primary progressive aphasia (nfvPPA), 9 semantic-bvFTD (sbvFTD). Fractional anisotropy (FA), mean diffusivity (MD), intracellular-volume fraction (ICVF), and orientation-dispersion index (ODI) were analysed using tract-based and GM-based spatial statistic at the voxel-wise level, with nonparametric and permutation-based methods. Suppo …

Corpus Callosum Structural Alterations in Essential Tremor with and Without Resting Tremor: A Multimodal MRI Study.

BACKGROUND: Essential tremor (ET) is a common movement disorder characterized by postural and kinetic tremor. Some patients also show restin … 27 HC). We performed a multimodal MRI evaluation (thickness, mean diffusivity [MD], and fractional anisotropy [FA]) of the CC's genu, body, and splenium, using different statistical approaches. We first performed a traditional group-based comparison, controlling for relevant covariates. Then, we used an unsupervised classification model based on MRI data to …

Association of Corticospinal Tract Asymmetry With Ambulatory Ability After Intracerebral Hemorrhage.

BACKGROUND: Ambulatory ability after intracerebral hemorrhage (ICH) is important to patients. We tested whether asymmetry between ipsi- and contra-lesional corticospinal tracts (CSTs) assessed by diffusion tensor imaging (DTI) is associated with post-ICH ambulation. METHODS: Patients with spontaneous supratentorial ICH were recruited from 8 US sites between 2017 and 2024. For each patient, fractional anisotropy (FA) asymmetry index (AI) was computed for the whole CST and on a subset of fibers restricted to the cerebral peduncle (CP). Clinical and radiographic features were collected. The prim…

Brain tissue integrity in neuromyelitis optica spectrum disorder through T1-w/T2-w ratio, MTR and DTI.

BACKGROUND: The presence of diffuse brain damage in normal-appearing white matter (NAWM) and gray matter (NAGM) in neuromyelitis optica spec … ach participant. The mean values of T1-w/T2-w ratio, magnetization transfer ratio (MTR), fractional anisotropy (FA), axial diffusivity (AD), mean diffusivity (MD), and radial diffusivity (RD) were obtained in NAWM, NAGM, as well as in global and hypointense lesion masks. Global lesions refer to those typically associated with aquaporin-4-IgG positive NMOSD. …

Dispersion-based cognitive intra-individual variability in former American football players: Association with traumatic encephalopathy syndrome, repetitive head impacts, and biomarkers.

Background: Exposure to repetitive head impacts (RHI), such as those experienced in American football, is linked to cognitive dysfunction la … ct index (CHII) measured RHI exposure. Lumipulse technology was used for CSF assays. DTI fractional anisotropy assessed white matter integrity. Coefficient of variation (CoV) measured d-CIIV. ANCOVA compared d-CIIV among groups (football versus control; TES-status). Pearson correlations and linear regressions tested associations between d-CIIV, RHI exposure, …

Воздействие когнитивной реабилитации и физических упражнений на структуру мозга при прогрессивном множественном склерозе: результаты испытания CogEx.

Ранее мы демонстрировали повышенный объем кортикальной серой материи (GM) у участников судебных процессов по делу CogEx, которые проводили когнитивную реабилитацию (CR). Здесь мы изучаем комбинированное воздействие CR и аэробных упражнений (EX) на региональные изменения в объемах мозга и целостности белых веществ (WM). Семьдесят три пациента были произвольно разбиты на четыре группы, которые получили комбинацию CR и EX или их фальшивые версии: CR + EX, CR + EX-sham, EX + CR-sham и CR-sham + EX-sham. Для включения в программу требуется диагностика прогрессивного множественного склероза (ПМС) и

Совпадение в аннотации оригинала
BACKGROUND: We previously showed increased cortical grey matter (GM) volume in CogEx trial participants who performed cognitive rehabilitati … acquired with a standardized protocol, and voxelwise variations of brain volumes and WM fractional anisotropy (FA) were analyzed. RESULTS: Baseline regional brain volumes and WM FA were comparable between groups. Voxelwise analyses at W12 and M9 revealed generalized volume reductions in all groups. We found different patterns of volumetric changes in the l …

Association between diffusion tensor imaging measurements and cognitive performances in people with multiple sclerosis: A systematic review and meta-analysis.

BACKGROUND: Alterations in structural connectivity of brain networks have been linked to complex cognitive functions in people with multiple … analysis indicated that the SDMT exhibited the greatest correlation with corpus callosum fractional anisotropy (FA) (r = 0.54, 95 % CI: 0.4 to 0.66, p-value < 0.001, I2 = 34.1 %, p-heterogeneity = 0.19) and mean diffusivity (MD) (r = -0.48, 95 % CI: 0.61 to -0.33, p-value < 0.001, I2 = 0 %, p-heterogeneity = 0.77), white matter FA (r = 0.39, 95 % CI: 0.24 to …

Tunable long-range spin transport in a van der Waals Fe3GeTe2/WSe2/Fe3GeTe2 spin valve.

The seamless integration of two-dimensional (2D) ferromagnetic materials with similar or dissimilar materials can widen the scope of low-power spintronics. In this regard, a vertical van der Waals (vdW) heterostructure of 2D ferromagnets with semiconducting transition metal dichalcogenides (TMDCs) forms magnetic junctions with exceptional stability and electrical control. Interestingly, 2D metallic Fe3GeTe2 (FGT) reveals above room temperature Curie temperatures and has large magneto anisotropy due to spin-orbit coupling. In addition, it also possesses topological states and a large Berry curv…

White matter microstructure of children with sensory over-responsivity is associated with affective behavior.

BACKGROUND: Sensory processing dysfunction (SPD) is linked to altered white matter (WM) microstructure in school-age children. Sensory over- … nd in matched children with neurodevelopmental concerns but not SOR. RESULTS: Global WM fractional anisotropy (FA) is negatively correlated with somatization and with emotional disturbance in the SOR group but not the non-SOR group. Also observed in children with SOR are positive correlations of radial diffusivity (RD) and free water fraction (FISO) with so …

Effects of mixed metal exposures on MRI diffusion features in the medial temporal lobe.

BACKGROUND: Environmental exposure to metal mixtures is common and may be associated with increased risk for neurodegenerative disorders inc … kness) and diffusion tensor imaging [mean (MD), axial (AD), radial diffusivity (RD), and fractional anisotropy (FA)] metrics. In exposed subjects, correlation, multiple linear, Bayesian kernel machine regression, and mediation analyses were employed to examine effects of single- or mixed-metal predictor(s) and their interactions on MTL structural and neurops …

Structural projections to the nucleus accumbens link to impulsive components of human risk preference.

Functional responses in the Nucleus Accumbens (NAcc) to risk- and reward-relatedcues can predict real-life risk-taking behavior. Since NAcc … set ofhypotheses concerning the association between different risk preference factorsand fractional anisotropy (or FA, which is sensitive to fiber coherence) forprojections to the NAcc from Medial PreFrontal Cortex (MPFC), Anterior Insula,Amygdala, and an inferior tract from the Ventral Tegmental Area (iVTA). Wetested our hypotheses in a community sample of …

Semi-supervised auto-segmentation method for pelvic organ-at-risk in magnetic resonance images based on deep-learning.

BACKGROUND AND PURPOSE: In radiotherapy, magnetic resonance (MR) imaging has higher contrast for soft tissues compared to computed tomograph … taset, ensemble learning and post-processing methods were employed. Additionally, when dealing with anisotropy and limited sample sizes, the 2D model outperformed the 3D model in terms of performance.

Quantitative muscle magnetic resonance imaging in limb-girdle muscular dystrophy type R1 (LGMDR1): A prospective longitudinal cohort study.

Limb-girdle muscular dystrophy (LGMD) type R1 (LGMDR1) is the most common subtype of LGMD in Europe. Prospective longitudinal data, includin … ion tensor imaging. The qMRI values of fat fraction (FF), water T2 relaxation time (T2), fractional anisotropy, mean diffusivity, axial diffusivity and radial diffusivity were analysed. Within the clinical outcome measures, significant deterioration between baseline and follow-up was found for ACTIVLIM (p = 0.029), QMFM (p = 0.012). Analysis of qMRI paramete …