Background: Gadolinium (Gd)-based delayed-enhancement MRI (DEMRI) identifies nonviable myocardium but is nonspecific and may overestimate nonviable territory. Manganese (Mn(2+))-enhanced MRI (MEMRI) denotes specific Mn(2+) uptake into viable cardiomyocytes. We performed a dual-contrast myocardial assessment in a porcine ischemia-reperfusion (IR) model to test the hypothesis that combined DEMRI and MEMRI identifies viable infarct border zone (BZ) myocardium in vivo.
Methods And Results: Sixty-minute left anterior descending coronary artery IR injury was induced in 13 adult swine. Twenty-one days post-IR, 3-T cardiac MRI was performed. MEMRI was obtained after injection of 0.7 mL/kg Mn(2+) contrast agent. DEMRI was then acquired after injection of 0.2 mmol/kg Gd. Left ventricular (LV) mass, infarct, and function were analyzed. Subtraction of MEMRI defect from DEMRI signal identified injured BZ myocardium. Explanted hearts were analyzed by 2,3,5-triphenyltetrazolium chloride stain and tissue electron microscopy to compare infarct, BZ, and remote myocardium. Average LV ejection fraction was reduced (30±7%). MEMRI and DEMRI infarct volumes correlated with 2,3,5-triphenyltetrazolium chloride stain analysis (MEMRI, r=0.78; DEMRI, r=0.75; P<0.004). MEMRI infarct volume percentage was significantly lower than that of DEMRI (14±4% versus 23±4%; P<0.05). BZ MEMRI signal-to-noise ratio (SNR) was intermediate to remote and core infarct SNR (7.5±2.8 versus 13.2±3.4 and 2.9±1.6; P<0.0001), and DEMRI BZ SNR tended to be intermediate to remote and core infarct SNR (8.4±5.4 versus 3.3±0.6 and 14.3±6.6; P>0.05). Tissue electron microscopy analysis exhibited preserved cell structure in BZ cardiomyocytes despite transmural DEMRI enhancement.
Conclusions: The dual-contrast MEMRI-DEMRI detects BZ viability within DEMRI infarct zones. This approach may identify injured, at-risk myocardium in ischemic cardiomyopathy.
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http://dx.doi.org/10.1161/CIRCIMAGING.110.960591 | DOI Listing |
Int J Mol Sci
January 2025
Department of Cell Biology, IFOM ETS-The AIRC Institute of Molecular Oncology, Via Adamello, 16, 20139 Milan, Italy.
The regeneration of endothelial cells (ECs) lining arteries, veins, and large lymphatic vessels plays an important role in vascular pathology. To understand the mechanisms of atherogenesis, it is important to determine what happens during endothelial regeneration. A comparison of these processes in the above-mentioned vessels reveals both similarities and some significant differences.
View Article and Find Full Text PDFInvest Ophthalmol Vis Sci
January 2025
Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York, New York, United States.
Purpose: To assess the preferential sites of retinal capillary occlusion at the parafovea in patients with sickle cell disease (SCD) using optical coherence tomography angiography (OCT-A).
Methods: OCT-A scans from 107 patients with SCD and 51 race-matched unaffected controls were obtained using a commercial spectral domain-OCT system. At least eight sequential 3 × 3 mm scans centered at the fovea were acquired and averaged for image analysis.
Sci Rep
January 2025
Thermal and Energetic Systems Studies Laboratory (LESTE), LR99ES31, College of Engineering, University of Monastir, 5000, Monastir, Tunisia.
Using the RANS approach with the standard k-ω turbulence model, this study offers a novel investigation into the dynamic and thermal properties of turbulent impinging jet arrays. Our study examines the combined effect of the number of jets (N) and the jet-jet spacing (S) on flow mechanisms and heat transfer performance, which is unique compared to previous research that frequently focuses on the individual effects of parameters. Through the investigation of the turbulent kinetic energy, friction coefficient, velocity contours, streamlines, pressure contours, and local and mean Nusselt numbers, we provide important information about how these parameters impact flow dynamics.
View Article and Find Full Text PDFJ Control Release
January 2025
Department of Cardiology, Zhongda Hospital, School of Medicine, Southeast University, 87 Dingjiaqiao, Nanjing 210009, China. Electronic address:
Treatment of myocardial ischemia-reperfusion (MI/R) injury still faces the lack of clinically approved drugs. Apelin-13 is a highly promising drug candidate of MI/R injury, but hampered by its extremely short half-life in plasma. This calls for efficient and smart delivering system for Apelin-13 delivery, but has not been reported.
View Article and Find Full Text PDFFree Neuropathol
January 2024
Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University Vienna, Vienna, Austria.
Just 40 years ago, Europe was divided into the Eastern communist bloc, which included the Czechoslovak Socialist Republic (ČSSR) and was dominated by the now historical Soviet Union, and the Western bloc comprising democracies such as Austria. The Iron Curtain, a heavily guarded and deadly border zone, separated the two blocs and constrained, in prison style, the populations of the Eastern bloc. The present neuropathological article relates the sad fate of František Faktor, a 33 years-old Czech who was shot by ČSSR border guards when attempting to flee to Austria at the border between and .
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