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Detection of spinal long fiber tract degeneration in HSP: Improved diffusion tensor imaging.

Spinal diffusion tensor imaging (sDTI) is still a challenging technique for selectively evaluating anatomical areas like the pyramidal tracts (PT), dorsal columns (DC), and anterior horns (AH) in clinical routine and for reliably quantifying white matter anisotropy and diffusivity. In neurodegenerative diseases, the value of sDTI is promising but not yet well understood. The objective of this prospective, single-center study was to evaluate the long fiber tract degeneration within the spinal cord in normal aging (n = 125) and to prove its applicability in pathologic conditions as in patients w…

Compressibility and High-Pressure Structure of CaMg2Bi2 and YbMg2Bi2.

Compounds with the formula AM2X2 in the CaAl2Si2 structure type have garnered increasing interest across various solid-state research domain … ghting the more compressible and flexible octahedral A-Bi bonds as the primary contributors to this anisotropy. Moreover, we observed a phase transition in both CaMg2Bi2 and YbMg2Bi2 at pressures above 9.6 and 8.7 GPa, respectively. The newly identified high-pressure phase exhibits a distortion of the original CaAl2Si2 structure with space group C2/m. This h …

MRI biomarkers of post-stroke stem cell implantation and motor recovery: systematic review of clinical trials.

BACKGROUND: Stroke causes long-term disability, and stem cell implantation may augment neural repair. Advanced MRI may provide objective bio … acked robust controls and were accompanied by preserved or increased corticospinal tract fractional anisotropy and greater task-related BOLD activity within motor regions (BA4/BA6). MNC trials reported NIHSS reductions and later increases in relative FA; the single MRS study suggested rising N-acetylaspartate with decreasing choline. Evidence for NSCs was li …

Exploring multifunctional behavior in X2CoGa (X = Cu, Ag, Zn, Nb) Heusler alloys via first-principles calculations.

In the present work, first-principles density functional theory calculations are performed to investigate the structural, spin-polarized ele … s reveal that both compounds satisfy the Born stability criteria and are ductile in nature. Elastic anisotropy analysis indicates that Nb2CoGa exhibits a near-isotropic behavior, consistent with an anisotropy factor close to unity (AZ ≈ 0.95). The higher Debye temperature and lattice thermal conductivity of Nb2CoGa imply stronger interatomic bonding, highlig …

Continuous Monitoring of Hydric Deformation in Macigno Sandstone After Thermal Conditioning.

Hydric deformation can contribute to progressive damage in building stones, particularly when moisture-induced strains interact with pre-existing fabric anisotropy and thermally induced microstructural changes. Six Macigno sandstone prisms (20 mm × 20 mm × 200 mm), three with the longitudinal axis orthogonal to bedding (MTO) and three parallel to bedding (MTP), were examined after drying at 60 °C and after sequential thermal conditioning at 350 and 500 °C. At each stage, hydric deformation was continuously monitored during 8400 min of water immersion, and at the end of each test, water absorpt…

Damage Mechanisms of Oil Shale Induced by Drilling Fluid Invasion under Coupled Stress-Seepage Conditions.

Shale oil exploration and development is important to meet our global energy demand. To improve wellbore stability in oil shale formations, … il shale cores and ambient relative humidity and water potential. The oil shale exhibits pronounced anisotropy, and the coupled stress-seepage response is strongly influenced by this anisotropy. The strength of samples using oil-based drilling fluids is significantly higher than using water-based drilling fluids, with increases reaching up to 71%, confirming …

Diffusion tensor imaging parameters in the presence of optic neuritis in multiple sclerosis.

OBJECTIVE: This study examined how different diffusion tensor imaging (DTI) acquisition planes affect diffusion tensor indices in multiple s … xerted a significant main effect on ten parameters following FDR correction - among them Fractional Anisotropy, Apparent Diffusion Coefficient, Mean Diffusivity, and Radial Diffusivity - with axial acquisitions consistently yielding higher diffusivity and anisotropy values than coronal ones. CONCLUSION: Optic nerve DTI parameters did not differ significantl …

Compact piezo-driven rotatable magnetic force microscope in a cryogen-free magnet.

Achieving in situ rotation of scanning probe microscopes (SPMs) within high-field magnets presents significant technical challenges while remaining essential for micron-scale magnetic anisotropy studies. Here, we demonstrate a compact piezoelectrically driven rotatable magnetic force microscope operable within a standard 50 mm bore cryogen-free superconducting magnet, achieving fields up to 12 T and temperatures down to 2 K. The microscope features a nested coaxial piezoelectric scanning tube (PST) design sharing a common base. In this design, the outer PST provides rigid support for the tip h…

Effect of glucocorticoid therapy on brain white matter microstructure in thyroid-associated ophthalmopathy: a longitudinal diffusion kurtosis imaging study.

To investigate the changes in brain white matter microstructure in patients with thyroid-associated ophthalmopathy (TAO) before and after gl … to evaluate the mean kurtosis (MK), axial kurtosis (AK), radial kurtosis (RK), kurtosis fractional anisotropy, fractional anisotropy (FA) and mean diffusion of brain white matter. At baseline, TAO patients showed significantly decreased MK, AK, RK and FA in extensive white matter tracts compared to controls. After therapy, increased MK and AK were observed …

Характеристика повреждения тканей внутри и вокруг парамагнитных позвонков при многоразовом склерозе.

ВАЖНЯЯ ОСНОВА И ЦЕЛЬ: Повреждения парамагнитных ободов (ПРЛ) представляют собой визуальную биомаркировку хронического воспаления в MS, которые связаны с более агрессивными заболеваниями. Однако точные характеристики тканей и степень их повреждения, особенно в том, что касается соединенных аксоновых трактов, не вполне понятны. Количественные диффузионные измерения тканей и волокна могут дать более полное представление об этих явлениях. МАТЕРИАЛЫ И МЕТОДЫ: В этом исследовании приняли участие сто пятнадцать человек с MS. Количественное картирование и DWI были приобретены на 3T MRI-сканере. ПРЛ бы

Совпадение в аннотации оригинала
BACKGROUND AND PURPOSE: Paramagnetic rim lesions (PRLs) are an imaging biomarker of chronic inflammation in MS that are associated with more … tracts and PRL-connected versus nonconnected surrounding tracts. DWI metrics, including fractional anisotropy (FA), quantitative anisotropy (QA), mean diffusivity, axial diffusivity, radial diffusivity, isotropy, and restricted diffusion imaging, were compared between these tracts and within PRLs and non-PRL lesions themselves. RESULTS: Tissue within PRLs …

Exploring the Role of Neuropeptide PACAP in Cytoskeletal Function Using Spectroscopic Methods.

The behavior and presence of actin-regulating proteins are characteristic of various clinical diseases. Changes in these proteins significan … PACAP6-38, measuring their binding to actin monomers via fluorescence spectroscopy and steady-state anisotropy. Functional polymerization tests were used to track changes in fluorescent intensity over time. Unlike PACAP27, PACAP38 and PACAP6-38 significantly reduced the fluorescence emission of Alexa488-labeled actin monomers and increased their anisotropy, …

Monoexponential and advanced diffusion-weighted imaging for hepatic fibrosis staging based on high inter-examiner reliability.

OBJECTIVES: To determine the diagnostic efficiencies of multiple diffusion-weighted imaging (DWI) techniques for hepatic fibrosis (HF) stagi … enrolled 48 HVs, 59 EHF patients, and 38 AHF patients. Mean, radial, and axial kurtosis; fractional anisotropy; mean, radial, and axial diffusivity; and α exhibited excellent reliability (ICCs: 0.80-0.98). Fractional anisotropy of kurtosis, f, and apparent diffusion coefficient showed good reliability (ICCs: 0.69-0.92). The real (0.58-0.67), pseudo- (0.27-0. …

White Matter Microstructural Differences between Essential Tremor and Parkinson Disease, Evaluated Using Advanced Diffusion MRI Biomarkers.

BACKGROUND: Essential tremor (ET) is a common slowly-progressive neurologic disorder. It is predominantly characterized by kinetic tremors i … ners (General Electric (GE) and Philips) with different numbers of diffusion directions. Fractional anisotropy maps were generated by the Oxford Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB) Software Library (FSL), and FBA was performed using MRtrix3 to obtain fiber density, fiber bundle, and fiber density bundle cross-section. RESUL …

Field-induced slow magnetic relaxation behaviours in binuclear cobalt(II) metallocycles and exchange-coupled clusters.

Precise control of the structures and magnetic properties of a molecular material constitutes an important challenge to realize tailor-made … ions in 2 due to the long bimp ligands. Interestingly, both the complexes show significant magnetic anisotropy and thus exhibit slow magnetic relaxation under an external dc field originating from spin-lattice relaxation. Detailed theoretical calculations were further applied to understand the magnetic interactions and magnetic anisotropy in 1 and 2. The for …

Micropatterned conductive elastomer patch based on poly (glycerol sebacate)-graphene for cardiac tissue repair.

Preparing a micropatterned elastomer film with characteristics that can simulate the mechanical properties, anisotropy, and electroactivity of natural myocardial tissues is crucial in cardiac tissue engineering after myocardial infarction (MI). Therefore, in this study, we developed several elastomeric films with a surface micropattern based on poly (glycerol sebacate) (PGS) and graphene (Gr). These films have sufficient mechanical strength (0.6 ± 0.1-3.2 ± 0.08 MPa) to withstand heartbeats, and the micropatterned structure also satisfies the natural myocardium anisotropy in the transverse and…

Prenatal Exposure to Endocrine-Disrupting Chemicals and Subsequent Brain Structure Changes Revealed by Voxel-Based Morphometry and Generalized Q-Sampling MRI.

Previous studies have indicated that prenatal exposure to endocrine-disrupting chemicals (EDCs) can cause adverse neuropsychiatric disorders … morphometry (VBM) and generalized q-sampling imaging (GQI) mapping-including generalized fractional anisotropy (GFA), normalized quantitative anisotropy (NQA), and the isotropic value of the orientation distribution function (ISO)-were obtained in teenagers 13-16 years of age in order to find the association between maternal EDC concentrations and possible b …

Diagnostic Approach to Traumatic Axonal Injury of the Optic Radiation in Mild Traumatic Brain Injury.

We describe a diffusion tensor tractography-based diagnostic approach to traumatic axonal injury of the optic radiation in a patient who showed visual field defect after mild traumatic brain injury. A 43-yr-old female patient experienced head trauma during a motor vehicle accident. After the head trauma, she noticed visual disturbance. Peripheral field defects were detected in both eyes on the Humphrey visual field test. After diffusion tensor tractography-based reconstruction of the optic radiation, We determined the fractional anisotropy and fiber number of each whole optic radiation. Four r…

Persistence of abnormalities in white matter in children with type 1 diabetes.

AIMS/HYPOTHESIS: Prior studies suggest white matter growth is reduced and white matter microstructure is altered in the brains of young chil … re to hyperglycaemia, averaged over the time since diagnosis, was associated with higher fractional anisotropy (p = 0.037). Fractional anisotropy was positively correlated with performance (p < 0.002) and full-scale IQ (p < 0.02). CONCLUSIONS/INTERPRETATION: These results suggest that hyperglycaemia is associated with altered white matter development, which …

Brain white matter fiber tracts involved in post-transjugular intrahepatic portosystemic shunt hepatic myelopathy.

We aimed to detect alterations in diffusion characteristics of brain white matter in hepatic myelopathy (HM) patients. Liver cirrhosis patie … tics and diffusion metrics were also calculated. HM patients showed widespread decreased fractional anisotropy values in association fibers, callosal fibers, thalamic fibers, and limbic system fibers (P<0.01, family-wise error-corrected) compared with healthy controls. In addition, HM patients showed lower fractional anisotropy values in the corpus callosum, …

Reciprocal white matter alterations due to 16p11.2 chromosomal deletions versus duplications.

Copy number variants at the 16p11.2 chromosomal locus are associated with several neuropsychiatric disorders, including autism, schizophreni … is reciprocal relationship in white matter organization, showing widespread increases of fractional anisotropy throughout the supratentorial white matter in pediatric deletion carriers and, in contrast, extensive decreases of white matter fractional anisotropy in pediatric and adult duplication carriers. We find associations of these white matter alterations …