Purpose: To demonstrate a circular EPI (CEPI) sequence as well as a generalized EPI reconstruction for fast fMRI with parallel imaging acceleration.
Methods: The CEPI acquisition was constructed using variable readout lengths and maximum ramp sampling as well as blipped-CAIPI z-gradient encoding for simultaneous multislice (SMS) and 3D volumetric imaging. A signal equation model with constant and linear phase terms was used to iteratively reconstruct images with low ghosting. Simulation, phantom, and human imaging experiments including audio/visual fMRI were performed at 3T using a 52-channel coil.
Results: Application of CEPI gradients with duration of 27 ms covering a 22-cm FOV at a 64 × 64 pixel resolution in SMS and 3D acquisitions resulted in images with comparable quality to those of standard Cartesian EPI. With parallel imaging techniques robust detection of BOLD fMRI activation with temporal sampling down to 275 ms was possible. The high temporal resolution enabled higher activation statistics at a penalty in increased noise and residual aliasing. The un-accelerated 3D acquisition showed large temporal instability compared with a standard 2D acquisition.
Conclusion: Nonuniform sampling and generalized image reconstructions can be applied to EPI acquisitions including those with blipped-CAIPI z gradients. The same gradients can be used for either SMS or 3D acquisitions providing identical coverage.
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http://dx.doi.org/10.1002/mrm.27522 | DOI Listing |
Sci Rep
December 2024
Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore, 138673, Republic of Singapore.
Signaling interplay between the histamine 1 receptor (H1R) and transient receptor potential cation channel subfamily V member 1 (TRPV1) in mediating histaminergic itch has been well-established in mammalian models, but whether this is conserved in humans remains to be confirmed due to the difficulties in obtaining human sensory neurons (SNs) for experimentation. Additionally, previously reported species-specific differences in TRPV1 function indicate that use of human SNs is vital for drug candidate screening to have a higher chance of identifying clinically effective TRPV1 antagonists. In this study, we built a histamine-dependent itch model using peripheral SNs derived from human induced pluripotent stem cells (hiPSC-SNs), which provides an accessible source of human SNs for pre-clinical drug screening.
View Article and Find Full Text PDFJ Neurosci
December 2024
Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029
The neurotransmitter dopamine (DA) has a multifaceted role in healthy and disordered brains through its action on multiple subtypes of dopaminergic receptors. How modulation of these receptors influences learning and motivation by altering intrinsic brain-wide networks remains unclear. Here we performed parallel behavioral and resting-state functional MRI experiments after administration of two different DA receptor antagonists in male and female macaque monkeys.
View Article and Find Full Text PDFBiosensors (Basel)
November 2024
Department of Electrical and Computer Engineering, University of Manitoba, Winnipeg, MB R3T 5V6, Canada.
In this paper, we present a microfluidic flow cytometer for simultaneous imaging and dielectric characterization of individual biological cells within a flow. Utilizing a combination of dielectrophoresis (DEP) and high-speed imaging, this system offers a dual-modality approach to analyze both cell morphology and dielectric properties, enhancing the ability to analyze, characterize, and discriminate cells in a heterogeneous population. A high-speed camera is used to capture images of and track multiple cells in real-time as they flow through a microfluidic channel.
View Article and Find Full Text PDFMol Autism
December 2024
Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Background: Angelman syndrome (AS), a severe neurodevelopmental disorder resulting from the loss of the maternal UBE3A gene, is marked by changes in the brain's white matter (WM). The extent of WM abnormalities seems to correlate with the severity of clinical symptoms, but these deficits are still poorly characterized or understood. This study provides the first large-scale measurement of WM volume reduction in children with AS.
View Article and Find Full Text PDFBMJ Open
December 2024
Division of Endocrinology, Metabolism, and Lipids; Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
Introduction: People with cystic fibrosis (PwCF) are at high risk for developing cystic fibrosis (CF)-related diabetes (CFRD), which worsens morbidity and mortality. Although the pathological events leading to the development of CFRD are complex and not completely understood, dietary factors may play a role. For example, habitual intake of dietary added sugar (i.
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