Purpose: To use magnetic resonance imaging (MRI) at two field strengths to assess healthy adults' regional myocardial noncontrast (native) T1 relaxation time distribution, and global myocardial native T1 between sexes and across age groups.
Materials And Methods: In all, 84 healthy volunteers underwent MRI at 1.5T and 3.0T. T1 maps were acquired in three left ventricular short axis slices using an optimized modified Look-Locker inversion recovery investigational prototype sequence. T1 measurements in msec were calculated from 16 regions-of-interest, and a global T1 value from all evaluable segments per subject. Associations were assessed with a multivariate linear regression model.
Results: In total, 1297 (96.5%) segments were evaluable at 1.5T and 1263 (94.0%) segments at 3.0T. Native T1 was higher in septal than lateral myocardium (1.5T: 956.3 ± 44.4 vs. 939.2 ± 54.2 msec; P < 0.001; 3.0T: 1158.2 ± 45.9 vs. 1148.9 ± 56.9 msec; P = 0.012). Native T1 decreased with increasing age in females but not in males. Among lowest age tertile (<33 years) global native T1 was higher in females than in males at 1.5T (960.0 ± 20.3 vs. 931.5 ± 22.2 msec, respectively; P = 0.003) and 3.0T (1166.5 ± 19.7 vs. 1130.2 ± 20.6 msec; P < 0.001). No sex differences were observed in upper age tertile (≥55 years) at 1.5T (937.7 ± 25.4 vs. 934.7 ± 22.3 msec; P = 0.762) or 3.0T (1153.0 ± 30.0 vs. 1132.3 ± 23.5 msec; P = 0.056). Association of global native T1 to age (P = 0.002) and sex (P < 0.001) was independent of field strength and body size.
Conclusion: In healthy adults, native T1 values are highest in the ventricular septum. Global native T1 was inversely associated with age in women, but not in men. J. Magn. Reson. Imaging 2016;44:541-548.
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http://dx.doi.org/10.1002/jmri.25217 | DOI Listing |
Appl Magn Reson
October 2024
Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520 USA.
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January 2025
Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, Hong Kong SAR 999077, P. R. China.
Bioimaging probes based on carbon dots (CDs) can become a useful replacement for existing commercial probes, benefiting clinical diagnostics. While the development of dual-mode CD-based probes for magnetic resonance imaging (MRI), which provides the ability for photoluminescence (PL) detection at the same time, is ongoing, several challenges have to be addressed. First, most of the CD-based probes still emit at shorter wavelengths (blue/green spectral range), which is harmful to biological objects or have very low PL intensity in the biological window of tissue transparency (red/near-infrared spectral range).
View Article and Find Full Text PDFSci Rep
January 2025
Department of Pharmacology and Experimental Therapeutics; MS 1015, College of Pharmacy and Pharmaceutical Sciences, The University of Toledo, Health Education Building; Room 282E, 3000 Arlington Ave, Toledo, OH, 43614, USA.
We previously demonstrated that the inability of primary endothelial cilia to sense fluid shear stress can lead to nitric oxide (NO) deficiency and cause hypertension (HTN). Decreased biosynthesis of NO contributes to cerebral amyloid angiopathy in Alzheimer's disease (AD) patients through increased deposition of amyloid beta (Aβ). However, the molecular mechanisms underlying the pathogenesis of HTN and AD are incompletely understood.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
College of Physics Science and Technology, Yangzhou University, Yangzhou 225009, China.
Developing high-performance solar cells is a practical way to improve clean energy conversion efficiency. However, the performance of solar cells faces challenges such as fast carrier combination, poor stability, and limited solar light harvesting. Herein, we propose a strategy by decorating periodic holes in two-dimensional (2D) porous carbon-nitrogen (CN) materials with a zero-dimensional (0D) semiconducting (ZnO) cluster.
View Article and Find Full Text PDFHeliyon
January 2025
Division of Polymer Chemistry, Department of Chemistry, Atomic Energy Commission, P.O. Box: 6091, Damascus, Syrian Arab Republic.
The degree of sulfonation (DS) is a key property of sulfonated polymers, as it significantly influences their swelling behaviour, conductivity and mechanical properties. Accurately determining the DS is essential for optimizing these materials for various applications. In this work, the DS of sulfonated poly (ether ether ketone) (SPEEK) was evaluated using a combination of analytical techniques, including titration, back titration, Fourier Transform Infrared (FTIR), Ultra-Violet (UV) and proton nuclear magnetic resonance (H NMR) spectroscopies, Thermogravimetric analysis (TGA), Rutherford backscattering (RBS) and particle induced X-ray emission (PIXE) analysis.
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