Application of HN-FeO Nanoparticles for Prostate Cancer Magnetic Resonance Imaging in an Animal Model.

This paper presents the efficacy of a contrast agent based on HN-FeO nanoparticles for the detection of prostate cancer in an animal model using a preclinical 9.4 T MRI system. The relaxivities r and r of the nanoparticles were 6.

H Spin-Lattice Relaxation Processes in Solutions of HN-FeO Nanoparticles: Insights from NMR Relaxometry.

H spin-lattice relaxation experiments have been performed for water and glycerol/water solutions of HN-FeO superparamagnetic nanoparticles (NPs) of about 7 nm diameter. The experiments encompass a broad frequency range covering 3 orders of magnitude, from 10 kHz to 10 MHz (referring to H resonance frequency), and have been performed in the temperature range from 298 to 313 K, varying the concentration of the superparamagnetic species. This extensive dataset has been used for twofold purposes.

X-ray-Sensitive Doped CaF-Based MRI Contrast Agents for Local Radiation Dose Measurement.

Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose.

FeO Magnetic Nanoparticles Obtained by the Novel Aerosol-Based Technique for Theranostic Applications.

This work is aimed at presenting a novel aerosol-based technique for the synthesis of magnetite nanoparticles (Fe3O4 NPs) and to assess the potential medical application of their dispersions after being coated with TEA-oleate. Refinement of the processing conditions led to the formation of monodispersed NPs with average sizes of ∼5-6 nm and narrow size distribution ( of ∼3 nm). The NPs were coated with Triethanolammonium oleate (TEA-oleate) to stabilize them in water dispersion.

Contrast Enhancement in MRI Using Combined Double Action Contrast Agents and Image Post-Processing in the Breast Cancer Model.

Gd- and Fe-based contrast agents reduce T and T relaxation times, respectively, are frequently used in MRI, providing improved cancer detection. Recently, contrast agents changing both T/T times, based on core/shell nanoparticles, have been introduced. Although advantages of the T/T agents were shown, MR image contrast of cancerous versus normal adjacent tissue induced by these agents has not yet been analyzed in detail as authors considered changes in cancer MR signal or signal-to-noise ratio after contrast injection rather than changes in signal differences between cancer and normal adjacent tissue.

A truncated twisted solenoid RF phase gradient transmit coil for TRASE MRI.

Transmit array spatial encoding (TRASE) is an MR imaging technique that achieves k-space encoding through the use of phase gradients in the RF transmit field. Without requiring B gradient fields, TRASE MRI can be performed using significantly cheaper bi-planar permanent magnets or Halbach arrays. For TRASE encoding with these magnets, the twisted solenoid has been demonstrated as the most efficient RF transmit coil; however, this specific geometry results in a long coil with a relatively short imaging volume.

Target-Specific Magnetic Resonance Imaging of Human Prostate Adenocarcinoma Using NaDyF-NaGdF Core-Shell Nanoparticles.

We illustrate the development of NaDyF-NaGdF core-shell nanoparticles (NPs) for targeting prostate cancer cells using a preclinical 9.4 T magnetic resonance imaging (MRI) of live animals. The NPs composed of paramagnetic Dy and Gd (- and -contrast agents, respectively) demonstrate proton relaxivities of = 20.

Simple compensation method for improved half-pulse excitation profile with rephasing gradient.

Purpose: To improve the slice profile quality obtained by RF half-pulse excitation for 2D-UTE applications.

Methods: The overall first-order and zero-order phase errors along the slice-selection direction were obtained with the help of an optimization task to minimize the out-of-slice signal contamination from the calibration 1-dimenisonal (1D) profile data. The time-phase-error evolution was approximated from the k-space readout data, which were acquired primarily for correction of the readout trajectories during data regridding to the rectilinear grids.

A high duty-cycle, multi-channel, power amplifier for high-resolution radiofrequency encoded magnetic resonance imaging.

Objective: A radiofrequency (RF) power amplifier is an essential component of any magnetic resonance imaging (MRI) system. Unfortunately, no commercial amplifier exists to fulfill the needs of the transmit array spatial encoding (TRASE) MRI technique, requiring high duty cycle, high RF output power and independently controlled multi-channel capability. Thus, an RF amplifier for TRASE MRI is needed.

Bifunctional Pyrrolidin-2-one Terminated Manganese Oxide Nanoparticles for Combined Magnetic Resonance and Fluorescence Imaging.

Multimodal probes are an asset for simplified, improved medical imaging. In particular, fluorescence and magnetic resonance imaging (MRI) are sought-after combined capabilities. Here, we show that pyrrolidin-2-one-capped manganese oxide nanoparticles (MnO NPs) combine MRI with fluorescence microscopy to function as efficient bifunctional bio-nanoprobes.

Challenges in developing a magnetic resonance-compatible haptic hand-controller for neurosurgical training.

A haptic device is an actuated human-machine interface utilized by an operator to dynamically interact with a remote environment. This interaction could be virtual (virtual reality) or physical such as using a robotic arm. To date, different mechanisms have been considered to actuate the haptic device to reflect force feedback from the remote environment.

Influence of k-space trajectory corrections on proton density mapping with ultrashort echo time imaging: Application for imaging of short T2 components in white matter.

Purpose: To evaluate the impact of MR gradient system imperfections and limitations for the quantitative mapping of short T2* signals performed by ultrashort echo time (UTE) acquisition approach.

Materials And Methods: The measurement of short T2* signals from a phantom and a healthy volunteer study (8 subjects of average age 28 ± 4 years) were performed on a 3T scanner. The characteristics of the gradient system were obtained using calibration method performed directly on the measured subject or phantom.

Correction to: LyP-1 Conjugated Nanoparticles for Magnetic Resonance Imaging of Triple Negative Breast Cancer.

This article was updated to correct the spelling of B. Gino Fallone's name; it is correct as displayed above. Correction to: Mol Imaging Biol (2017).

LyP-1 Conjugated Nanoparticles for Magnetic Resonance Imaging of Triple Negative Breast Cancer.

Purpose: Triple-negative breast cancer (TNBC) does not express estrogen receptor, progesterone receptor, or Her2/neu. Both diagnosis and treatment of TNBC remain a clinical challenge. LyP-1 is a cyclic 9 amino acid peptide that can bind to breast cancer cells.

K-space trajectory mapping and its application for ultrashort Echo time imaging.

MR images are affected by system delays and gradient field imperfections which induce discrepancies between prescribed and actual k-space trajectories. This could be even more critical for non-Cartesian data acquisitions where even a small deviation from the assumed k-space trajectory results in severe image degradation and artifacts. Knowledge of the actual k-space trajectories is therefore crucial and can be incorporated in the reconstruction of high quality non-Cartesian images.

Site-specific conjugation of the quencher on peptide's N-terminal for the synthesis of a targeted non-spreading activatable optical probe.

Optical imaging offers high sensitivity and portability at low cost. The design of 'smart' or 'activatable' probes can decrease the background noise and increase the specificity of the signal. By conjugating a fluorescent dye and a compatible quencher on each side of an enzyme's substrate, the signal remains in its 'off ' state until it reaches the area where a specific enzyme is expressed.

MRI-based assessment of liver perfusion and hepatocyte injury in the murine model of acute hepatitis.

Objective: To assess alterations in perfusion and liver function in the concanavalin A (ConA)-induced mouse model of acute liver failure (ALF) using two magnetic resonance imaging (MRI)-based methods: dynamic contrast-enhanced MRI (DCE-MRI) with Gd-EOB-DTPA contrast agent and arterial spin labelling (ASL).

Materials And Methods: BALB/c mice were studied using a 9.4 T MRI system.

HyperCEST detection of cucurbit[6]uril in whole blood using an ultrashort saturation Pre-pulse train.

Xenon based biosensors have the potential to detect and localize biomarkers associated with a wide variety of diseases. The development and nuclear magnetic resonance (NMR) characterization of cage molecules which encapsulate hyperpolarized xenon is imperative for the development of these xenon biosensors. We acquired (129) Xe NMR spectra, and magnetic resonance images and a HyperCEST saturation map of cucurbit[6]uril (CB6) in whole bovine blood.

Evaluation of blood-brain barrier-stealth nanocomposites for in situ glioblastoma theranostics applications.

The blood-brain barrier (BBB) is a physiological structure of the blood vessels in the brain. The BBB efficiently traps most therapeutic drugs in the blood vessels and stops them from entering the brain tissue, resulting in a decreased therapeutic efficiency. In this study, we developed BBB-stealth nanocomposites composed of iron oxide (Fe3O4) nanoparticles (NPs) as a safe nanocarrier for glioblastoma therapy.

Hyperpolarized and inert gas MRI: the future.

Magnetic resonance imaging (MRI) is a potentially ideal imaging modality for noninvasive, nonionizing, and longitudinal assessment of disease. Hyperpolarized (HP) agents have been developed in the past 20 years for MR imaging, and they have the potential to vastly improve MRI sensitivity for the diagnosis and management of various diseases. The polarization of nuclear magnetic resonance (NMR)-sensitive nuclei other than (1)H (e.

Symmetry of the fornix using diffusion tensor imaging.

Purpose: To: 1) Present fornix tractography in its entirety for 20 healthy individuals to assess variability. 2) Provide individual and groupwise whole tract diffusion parameter symmetry assessments prior to clinical application. 3) Compare whole tract diffusion parameter assessments with tract-based spatial statistics (TBSS).

Lactate storm marks cerebral metabolism following brain trauma.

Brain metabolism is thought to be maintained by neuronal-glial metabolic coupling. Glia take up glutamate from the synaptic cleft for conversion into glutamine, triggering glial glycolysis and lactate production. This lactate is shuttled into neurons and further metabolized.

White and gray matter contrast enhancement in MR images of the mouse brain in vivo using IR UTE with a cryo-coil at 9.4 T.

Background: The aim of this work was to assess the capability of high field MRI to image brain micro-structures containing various amount of myelin.

New Method: A cryogenic RF receiver coil (Bruker 'CryoProbe') and an ultra-short echo (UTE) 2D pulse sequence with and without inversion pulse were used for coronal brain MR imaging of a healthy C57BL/6J mouse. A 9.

Tractography of Meyer's Loop asymmetries.

Purpose: The purpose of the current study was to use diffusion tensor imaging (DTI) to conduct tractography of the optic radiations (OR) and its component bundles and to assess both the degree of hemispheric asymmetry and the inter-subject variability of Meyer's Loop (ML). We hypothesized that there are significant left versus right differences in the anterior extent of ML to the temporal pole (TP) in healthy subjects.

Materials And Methods: DTI data were acquired on a 3T Siemens MRI system using a single-shot Spin Echo EPI sequence.

Magnetic resonance microscopy for assessment of morphological changes in hydrating hydroxypropylmethylcellulose matrix tablets in situ-is it possible to detect phenomena related to drug dissolution within the hydrated matrices?

Purpose: So far, the hydrated part of the HPMC matrix has commonly been denoted as a "gel" or "pseudogel" layer. No MRI-based results have been published regarding observation of internal phenomena related to drug dissolution inside swelling polymeric matrices during hydration. The purpose of the study was to detect such phenomena.