Assessing functional impairment, therapeutic response and disease progression in patients with idiopathic pulmonary fibrosis (IPF) continues to be challenging. Hyperpolarized

Purpose We sought to develop and test a clinically feasible 1‐point Dixon, three‐dimensional (3D) radial acquisition strategy create isotropic 3D MR images of 129 Xe in the airspaces, barrier, red blood cells (RBCs) single breath. The approach was evaluated healthy volunteers subjects with idiopathic pulmonary fibrosis (IPF). Methods A calibration scan determined echo time at which RBCs barrier were 90° out phase. At this TE, interleaved dissolved gas‐phase acquired using reconstructed...

Hyperpolarized 129 Xe magnetic resonance imaging (MRI) using Dixon-based decomposition enables single-breath of in the airspaces, interstitial barrier tissues, and red blood cells (RBCs). However, methods to quantitatively visualize information from these images pulmonary gas transfer are lacking. Here, we introduce a novel method transform data into quantitative maps ventilation, RBC compartments.A total 13 healthy subjects 12 idiopathic fibrosis (IPF) underwent thoracic 1 H MRI...

Although some central aspects of pulmonary function (ventilation and perfusion) are known to be heterogeneous, the distribution diffusive gas exchange remains poorly characterized. A solution is offered by hyperpolarized 129Xe magnetic resonance (MR) imaging, because this can separately detected in lung's air spaces dissolved its tissues. Early dissolved-phase images exhibited intensity gradients that favored dependent lung. To quantitatively corroborate finding, we developed an interleaved,...

A variety of pulmonary pathologies, in particular interstitial lung diseases, are characterized by thickening the blood–gas barrier, and this results reduced gas exchange. Such diffusive impairment is challenging to quantify spatially, because distributions metabolically relevant gases (CO 2 O ) cannot be detected directly within lungs. Hyperpolarized (HP) 129 Xe a promising surrogate for these metabolic gases, MR spectroscopy imaging allow gaseous alveolar separately from dissolved red...

The spectral parameters of hyperpolarized 129 Xe exchanging between airspaces, interstitial barrier, and red blood cells (RBCs) are sensitive to pulmonary pathophysiology. This study sought evaluate whether the dynamics spectroscopy provide additional insight, with particular focus on quantifying cardiogenic oscillations in RBC resonance. spectra were dynamically acquired eight healthy volunteers nine subjects idiopathic fibrosis (IPF). FIDs collected every 20 ms (TE = 0.932 ms, 512 points,...

The goal of this work is to characterize and optimize gridding reconstruction 3D radial hyperpolarized (HP) 129 Xe MRI. In support objective, we developed a flexible, open source software package in MATLAB optimally reconstruct radially acquired, undersampled HP Using framework, demonstrate the effects 5 key parameters: overgridding, kernel function, sharpness, extent, density compensation algorithm. We further how each parameter can be tuned high‐resolution acquired image ventilated mouse....

Purpose The purpose of this work was to accurately characterize the spectral properties hyperpolarized 129 Xe in patients with idiopathic pulmonary fibrosis (IPF) compared healthy volunteers. Methods Subjects underwent breath‐hold spectroscopy, during which 38 dissolved‐phase free induction decays (FIDs) were acquired after reaching steady state (echo time/repetition time = 0.875/50 ms; bandwidth 8.06 kHz; flip angle≈22 °). FIDs averaged and then decomposed into multiple components using...

Network approaches provide sensitive biomarkers for neurological conditions, such as Alzheimer's disease (AD). Mouse models can help advance our understanding of underlying pathologies, by dissecting vulnerable circuits. While the mouse brain contains less white matter compared to human brain, axonal diameters compare relatively well (e.g. ~0.6 µm in and ~0.65-1.05 corpus callosum). This makes an attractive test bed novel diffusion imaging protocols. Remaining questions on accuracy...

ABSTRACT Different subgroups of feline leukemia virus (FeLV) use different host cell receptors for entry. Subgroup A FeLV (FeLV-A) is the that transmitted from cat to cat, suggesting cells expressing FeLV-A receptor are important targets at earliest stages infection. FeLV-B evolves in infected through acquisition cellular sequences related envelope gene. FeLV-Bs have been shown infect using Pit1 receptor, and some variants can a lower efficiency Pit2. Because these observations were made...

Abstract Background Tissue morphogenesis is a complex process whereby tissue structures self-assemble by the aggregate behaviors of independently acting cells responding to both intracellular and extracellular cues in their environment. During embryonic development, particularly important for organizing into tissues, although key regulatory events this are well studied isolation, number systems-level questions remain unanswered. This due, part, lack integrative tools that enable coupling...

Hypodense metastases are not always completely distinguishable from benign cysts in the liver using conventional Computed Tomography (CT) imaging, since two lesion types present with overlapping intensity distributions due to similar composition as well other factors including beam hardening and patient motion. This problem is extremely challenging for small lesions diameter less than 1 cm. To accurately characterize such lesions, multiple follow-up CT scans or additional Positron Emission...

Hyperpolarized (HP) media enable biomedical imaging applications that cannot be achieved with conventional MRI contrast agents. Unfortunately, quantifying HP images is challenging, because relaxation and radio-frequency pulsing generate spatially varying signal decay during acquisition. We demonstrate that, by combining center-out k-space sampling postacquisition keyhole reconstruction, voxel-by-voxel maps of regional magnetization can generated no additional data collection.

129 Xe interacts with biological media to exhibit chemical shifts exceeding 200 ppm that report on physiology and pathology. Extracting this functional information requires be measured precisely. Historically, have been reported relative the gas-phase resonance originating from pulmonary airspaces. However, frequency is not fixed-it affected by bulk magnetic susceptibility, as well Xe-N2 , Xe-Xe, Xe-O2 interactions. In study, we addressed introducing a robust method determine 0 reference in...

Abstract Purpose The interaction between 129 Xe atoms and pulmonary capillary red blood cells provides cardiogenic signal oscillations that display sensitivity to precapillary postcapillary hypertension. Recently, such have been spatially mapped, but little is known about optimal reconstruction or artifacts. In this study, we use digital phantom simulations specifically optimize keyhole for oscillation imaging. We then optimized method re‐establish healthy reference values quantitatively...

Abstract Eddy current fields, generated in an animal‐size superconducting NMR magnet by a nominally rectangular pulsed transverse gradient applied the vertical direction, have been studied measuring offset frequency of proton signal obtained from small spherical sample. Measurements were made, after various time delays, at nine different locations sample space. Analysis data shows that time‐dependent fields all are quite well accounted for superposition only four independent exponentially...

Bronchial stenosis in lung transplant recipients is a common disorder that adversely affects clinical outcomes. It evaluated by spirometry, CT scanning, and bronchoscopy with significant limitations. We hypothesize MRI using both ultrashort echo time (UTE) scans hyperpolarized (HP) 129 Xe gas can offer structural functional assessment of bronchial seen after transplantation. Six patients transplantation-related underwent HP UTE the same session. Three subsequently airway stent placement had...

The objective of our study was to identify the magnitude and distribution ventilation defect scores (VDSs) derived from hyperpolarized (HP)

Human parainfluenza virus type 3 (HPIV3) is a major cause of disease in newborns and infants. It also has striking potential to reinfect individuals throughout their lives, suggesting that HPIV3 does not induce lifelong immunity; however, the operative mechanism for failure prevent reinfection known. We have assessed infect nontransformed human T lymphocytes found cells are readily infected by virus. Productive infection requires activation results marked inhibition proliferation....

Abstract The switching of magnetic field gradients in MRI gives rise to eddy currents the structural components superconducting magnet systems. associated fieldscause intensity artifacts which are particularly severe some animal‐size We treat theoretically three mechanisms cause one‐dimensional projection images obtained by a spin‐echo technique. first is an off‐resonance effect, caused applying refocusing pulse before read compensation gradient has decayed sufficiently. other two spatial...

To study the mechanisms of inducible immunity to Haemophilus ducreyi infection in temperature-dependent rabbit model chancroid, we conducted passive immunization experiments and characterized inflammatory infiltrate chancroidal lesions. Polyclonal immunoglobulin G was purified from immune sera raised against H. 35000 whole-cell lysate or a pilus preparation naive control rabbits. Rabbits were passively immunized with 24 48 mg polyclonal intravenously, followed h after infusion by homologous...