Neonatal hypoxia–ischemia is one of the main causes of mortality and disability of newborns. To study the mechanisms of neonatal brain cell damage, we used a model of neonatal hypoxia–ischemia in seven-day-old rats, by annealing of the common carotid artery with subsequent hypoxia of 8% oxygen. We demonstrate that neonatal hypoxia–ischemia causes mitochondrial dysfunction associated with high production of reactive oxygen species, which leads to oxidative stress. Targeted delivery of antioxidants to the mitochondria can be an effective therapeutic approach to treat the deleterious effects of brain hypoxia–ischemia. We explored the neuroprotective properties of the mitochondria-targeted antioxidant SkQR1, which is the conjugate of a plant plastoquinone and a penetrating cation, rhodamine 19. Being introduced before or immediately after hypoxia–ischemia, SkQR1 affords neuroprotection as judged by the diminished brain damage and recovery of long-term neurological functions. Using vital sections of the brain, SkQR1 has been shown to reduce the development of oxidative stress. Thus, the mitochondrial-targeted antioxidant derived from plant plastoquinone can effectively protect the brain of newborns both in pre-ischemic and post-stroke conditions, making it a promising candidate for further clinical studies.

Purpose The aim of this study was to demonstrate the feasibility of fluorine‐19 (19F) MRI of the human lungs using octafluorocyclobutane (OFCB, C4F8). This gas has 8 magnetically equivalent fluorine nuclei and relatively long T1 and T2 (˜50 ms), which render it suitable as an MRI contrast agent. Previous experiments in small laboratory animals showed that OFCB could be successfully used as an alternative to the gases often used for 19F MRI (sulfur hexafluoride and perfluoropropane). Methods One male volunteer participated in this study. Immediately before an MRI scan, the volunteer inhaled the gas mixture—80% OFCB with 20% oxygen—and held his breath. Experiments were performed on a 0.5T whole‐body MR scanner with a customized transmit–receive coil tuned at 19F frequency. Fast spin echo in 2D and 3D modes was used for image acquisition. 2D images were obtained with in‐plane resolution of 10 × 10 mm2 without slice selection. 3D images were obtained with the voxel size of 10 × 10 × 30 mm2. Breath‐hold duration was 20 s for 2D and 40 s for 3D imaging, respectively. Results Anatomically consistent 19F MR images of the human lungs were obtained with SNR around 50 in 2D mode and 20 in 3D mode. 3D volumetric images of the lungs were reconstructed and provided physiologically reasonable volume estimates. Conclusion The application of OFCB enables informative 19F lung imaging even at low magnetic field strengths. The OFCB gas shows promise as an inhalable contrast agent for fluorine lung MRI and has a potential for clinical translation.

Particular applications in preclinical magnetic resonance imaging require the entire body of an animal to be imaged with sufficient quality. This is usually performed by combining regions scanned with small coils with high sensitivity or long scans using large coils with low sensitivity. Here, a metamaterial-inspired design employing a parallel array of wires operating on the principle of eigenmode hybridization was used to produce a small-animal imaging coil. The coil field distribution responsible for the coil field of view and sensitivity was simulated in an electromagnetic simulation package and the coil geometrical parameters were optimized for whole-body imaging. A prototype coil was then manufactured and assembled using brass telescopic tubes with copper plates as distributed capacitance. Its field distribution was measured experimentally using the B mapping technique and was found to be in close correspondence with the simulated results. The coil field distribution was found to be suitable for large field of view small-animal imaging and the coil image quality was compared with a commercially available coil by whole-body scanning of living mice. Signal-to-noise measurements in living mice showed higher values than those of a commercially available coil with large receptive fields, and rivalled the performance of small receptive field and high-sensitivity coils. The coil was deemed to be suitable for some whole-body, small-animal preclinical applications.

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The cover image, by Mikhail Zubkov et al., is based on the Research Article Small‐animal, whole‐body imaging with metamaterial‐inspired RF coil, https://doi.org/10.1002/nbm.3952.