Т mapping of rat lungs in F MRI using octafluorocyclobutane.

Purpose: To demonstrate the feasibility of using octafluorocyclobutane (OFCB, c-C F ) for T mapping of lungs in F MRI.

Methods: The study was performed at 7 T in three healthy rats and three rats with pulmonary hypertension. To increase the sensitivity of F MRI, a bent-shaped RF coil with periodic metal strips structure was used.

Design and first implementation of wireless square-shaped transmission line resonators in H MRI for small animal studies.

This work is dedicated to the development of a novel design for wireless transmission line resonators (TLRs). The TLRs are often considered as circular-shaped coils made up of two conductive circuits separated by a dielectric layer. We propose a square-shaped TLR design, wherein the coil has two square turns with two symmetrical gaps on each of the conductive layers, and the latter are rotated relative to each other by 90°.

Three-dimensional fast single-point macromolecular proton fraction mapping of the human brain at 0.5 Tesla.

Fast single-point macromolecular proton fraction (MPF) mapping is a recent magnetic resonance imaging (MRI) method enabling quantitative assessment of myelin content in neural tissues. To date, the reported technical implementations of MPF mapping utilized high-field MRI equipment (1.5 T or higher), while low-field applications might pose challenges due to signal-to-noise ratio (SNR) limitations and short .

F MRI of human lungs at 0.5 Tesla using octafluorocyclobutane.

Purpose: The aim of this study was to demonstrate the feasibility of fluorine-19 ( F) MRI of the human lungs using octafluorocyclobutane (OFCB, C F ). This gas has 8 magnetically equivalent fluorine nuclei and relatively long T and T (˜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 F MRI (sulfur hexafluoride and perfluoropropane).

Application of copper plates for frequency tuning of surface wired and wireless MRI coils.

This study shows how a copper plate could be used for frequency tuning of surface wired and wireless MRI coils. For this purpose, it is proposed to place the copper plate directly on their conducting circuit. This leads to increase in the resonance frequency of coils.

Computation of the resonance frequencies of the transmission line resonators used in MRI.

Stripline high frequency resonators or transmission line resonators (TLRs) manufactured as concentric RF coils at the opposite sides of a dielectric sheet serve as wireless self-resonant transmitters-receivers in MRI. Owing to their high quality factor relative to traditional RF coils composed of bulk inductor and capacitors, frequency selectivity of TLRs is high, making them promising elements for single-nucleus MRI. However, the computation of their resonance frequencies is cumbersome, and numerous mathematical mistakes and typos in publications lead to incorrect results.

Realization of F MRI oximetry method using perfluorodecalin.

Objective: To identify the technical aspects of the potential use of clinically approved perfluorodecalin (PFD, CF) for F magnetic resonance imaging (MRI) oximetry method at high magnetic field 7.05 T.

Materials And Methods: F T measurements were made on a set of PFD samples with different oxygen contents (0%, 21%, and 100%) at room (21 °C) and body temperature (37 °C).

Neuroprotective Effects of Mitochondria-Targeted Plastoquinone in a Rat Model of Neonatal Hypoxic⁻Ischemic Brain Injury.

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.

Small-animal, whole-body imaging with metamaterial-inspired RF coil.

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.

Neuroprotective Effects of Mitochondria-Targeted Plastoquinone and Thymoquinone in a Rat Model of Brain Ischemia/Reperfusion Injury.

We explored the neuroprotective properties of natural plant-derived antioxidants plastoquinone and thymoquinone (2-demethylplastoquinone derivative) modified to be specifically accumulated in mitochondria. The modification was performed through chemical conjugation of the quinones with penetrating cations: Rhodamine 19 or tetraphenylphosphonium. Neuroprotective properties were evaluated in a model of middle cerebral artery occlusion.

Magnetic resonance spectroscopy of the ischemic brain under lithium treatment. Link to mitochondrial disorders under stroke.

Recent evidence suggests that mitochondria are one of the main factors in the pathogenesis in different organs including brain. The pathogenesis after brain damage is caused not only by the change in bioenergetics, but also involves impairment of alternative functions of mitochondria, particularly those related to the control of cell death. In this study we evaluated partial metabolic pathways under the simulation of a stroke by using the occlusion of the middle cerebral artery in rats.