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Hyperpolarized xenon

Jörg Döpfert, Matthias Schnurr, Martin Kunth, Honor May Rose, Andreas Hennig, Leif Schröder
We propose a method to dynamically monitor the progress of an enzymatic reaction using NMR of hyperpolarized 129 Xe in a host-guest system. It is based on a displacement assay originally designed for fluorescence experiments that exploits the competitive binding of the enzymatic product on the one hand and a reporter dye on the other hand to a supramolecular host. Recently, this assay has been successfully transferred to NMR, using xenon as a reporter, cucurbit[6]uril as supramolecular host, and Hyper-CEST as detection technique...
December 23, 2017: Magnetic Resonance in Chemistry: MRC
Brandon Zanette, Elaine Stirrat, Salomeh Jelveh, Andrew Hope, Giles Santyr
PURPOSE: To map physiological gas exchange parameters using dissolved hyperpolarized (HP) 129 Xe in a rat model of regional radiation-induced lung injury (RILI) with spiral-IDEAL and the model of xenon exchange (MOXE). Results are compared to quantitative histology of pulmonary tissue and red blood cell (RBC) distribution. METHODS: Two cohorts (n=6 each) of age-matched rats were used. One was irradiated in the right-medial lung, producing regional injury. Gas exchange was mapped four weeks post-irradiation by imaging dissolved-phase HP 129 Xe using spiral-IDEAL at five gas exchange timepoints using a clinical 1...
December 14, 2017: Medical Physics
Gaëlle Milanole, Bo Gao, Audrey Paoletti, Grégory Pieters, Christophe Dugave, Eric Deutsch, Sofia Rivera, Frédéric Law, Jean-Luc Perfettini, Emilie Mari, Estelle Léonce, Céline Boutin, Patrick Berthault, Hervé Volland, François Fenaille, Thierry Brotin, Bernard Rousseau
Although Non-Small Cell Lung Cancer (NSCLC) is one of the main causes of cancer death, very little improvement has been made in the last decades regarding diagnosis and outcomes. In this study, a bimodal fluorescence/129 Xe NMR probe containing a xenon host, a fluorescent moiety and a therapeutic antibody has been designed to target the Epidermal Growth Factor Receptors (EGFR) overexpressed in cancer cells. This biosensor shows high selectivity for the EGFR, and a biological activity similar to that of the antibody...
December 15, 2017: Bioorganic & Medicinal Chemistry
Erin J Song, Chris R Kelsey, Bastiaan Driehuys, Leith Rankine
Hyperpolarized (129) Xenon-MRI (HP (129) Xe MRI) is an emerging imaging modality that allows assessment of both ventilation and gas transfer. Most research to date has focused on non-malignant pulmonary diseases. However, the capability of evaluating the two primary physiological processes of the lung (ventilation and gas transfer) makes HP (129) Xe MRI a promising imaging modality in the management of patients with lung cancer.
September 22, 2017: Journal of Medical Imaging and Radiation Oncology
Anupama Lakshmanan, George J Lu, Arash Farhadi, Suchita P Nety, Martin Kunth, Audrey Lee-Gosselin, David Maresca, Raymond W Bourdeau, Melissa Yin, Judy Yan, Christopher Witte, Dina Malounda, F Stuart Foster, Leif Schröder, Mikhail G Shapiro
Gas vesicles (GVs) are a unique class of gas-filled protein nanostructures that are detectable at subnanomolar concentrations and whose physical properties allow them to serve as highly sensitive imaging agents for ultrasound and MRI. Here we provide a protocol for isolating GVs from native and heterologous host organisms, functionalizing these nanostructures with moieties for targeting and fluorescence, characterizing their biophysical properties and imaging them using ultrasound and MRI. GVs can be isolated from natural cyanobacterial and haloarchaeal host organisms or from Escherichia coli expressing a heterologous GV gene cluster and purified using buoyancy-assisted techniques...
October 2017: Nature Protocols
Madhwesha R Rao, Neil J Stewart, Paul D Griffiths, Graham Norquay, Jim M Wild
Purpose To evaluate the feasibility of directly imaging perfusion of human brain tissue by using magnetic resonance (MR) imaging with inhaled hyperpolarized xenon 129 ((129)Xe). Materials and Methods In vivo imaging with (129)Xe was performed in three healthy participants. The combination of a high-yield spin-exchange optical pumping (129)Xe polarizer, custom-built radiofrequency coils, and an optimized gradient-echo MR imaging protocol was used to achieve signal sensitivity sufficient to directly image hyperpolarized (129)Xe dissolved in the human brain...
August 31, 2017: Radiology
M A Antonacci, Alex Burant, Wolfgang Wagner, Rosa T Branca
Continuous-flow spin-exchange optical pumping (SEOP) continues to serve as the most widespread method of polarizing (129)Xe for magnetic resonance experiments. Unfortunately, continuous-flow SEOP still suffers from as-yet unidentified inefficiencies that prevent the production of large volumes of xenon with a nuclear spin polarization close to theoretically calculated values. In this work we use a combination of ultra-low field nuclear magnetic resonance spectroscopy and atomic absorption spectroscopy (AAS) measurements to study the effects of dark Rb vapor on hyperpolarized (129)Xe in situ during continuous-flow SEOP...
June 2017: Journal of Magnetic Resonance
Erin B Adamson, Kai D Ludwig, David G Mummy, Sean B Fain
In the past decade, hyperpolarized (HP) contrast agents have been under active development for MRI applications to address the twin challenges of functional and quantitative imaging. Both HP helium (3 He) and xenon (129 Xe) gases have reached the stage where they are under study in clinical research. HP129 Xe, in particular, is poised for larger scale clinical research to investigate asthma, chronic obstructive pulmonary disease, and fibrotic lung diseases. With advances in polarizer technology and unique capabilities for imaging of129 Xe gas exchange into lung tissue and blood, HP129 Xe MRI is attracting new attention...
July 7, 2017: Physics in Medicine and Biology
Kerstin Demberg, Frederik Bernd Laun, Johannes Windschuh, Reiner Umathum, Peter Bachert, Tristan Anselm Kuder
Diffusion pore imaging is an extension of diffusion-weighted nuclear magnetic resonance imaging enabling the direct measurement of the shape of arbitrarily formed, closed pores by probing diffusion restrictions using the motion of spin-bearing particles. Examples of such pores comprise cells in biological tissue or oil containing cavities in porous rocks. All pores contained in the measurement volume contribute to one reconstructed image, which reduces the problem of vanishing signal at increasing resolution present in conventional magnetic resonance imaging...
February 2017: Physical Review. E
Shengjun Yang, Yaping Yuan, Weiping Jiang, Lili Ren, He Deng, Louis S Bouchard, Xin Zhou, Maili Liu
A new magnetic resonance imaging (MRI) molecular sensor for hydrogen sulfide detection and imaging using the nuclear spin resonance of hyperpolarized (129) Xe is developed. The designed MRI sensor employs cryptophane for NMR sensing, together with an azide group serving as a reaction site. It demonstrates a "proof-of-concept" that a fluorescent H2 S probe can be linked to a xenon-binding cryptophane and thereby converted into an MRI probe, which could provide a very generalizable template.
February 28, 2017: Chemistry: a European Journal
Qingbin Zeng, Qianni Guo, Yaping Yuan, Yuqi Yang, Bin Zhang, Lili Ren, Xiaoxiao Zhang, Qing Luo, Maili Liu, Louis-S Bouchard, Xin Zhou
Biothiols such as gluthathione (GSH), cysteine (Cys), homocysteine (Hcy), and thioredoxin (Trx) play vital roles in cellular metabolism. Various diseases are associated with abnormal cellular biothiol levels. Thus, the intracellular detection of biothiol levels could be a useful diagnostic tool. A number of methods have been developed to detect intracellular thiols, but sensitivity and specificity problems have limited their applications. To address these limitations, we have designed a new biosensor based on hyperpolarized xenon magnetic resonance detection, which can be used to detect biothiol levels noninvasively...
February 9, 2017: Analytical Chemistry
Francis T Hane, Tao Li, Peter Smylie, Raiili M Pellizzari, Jennifer A Plata, Brenton DeBoef, Mitchell S Albert
The Hyperpolarized gas Chemical Exchange Saturation Transfer (HyperCEST) Magnetic Resonance (MR) technique has the potential to increase the sensitivity of a hyperpolarized xenon-129 MRI contrast agent. Signal enhancement is accomplished by selectively depolarizing the xenon within a cage molecule which, upon exchange, reduces the signal in the dissolved phase pool. Herein we demonstrate the in vivo detection of the cucurbit[6]uril (CB6) contrast agent within the vasculature of a living rat. Our work may be used as a stepping stone towards using the HyperCEST technique as a molecular imaging modality...
January 20, 2017: Scientific Reports
K Qing, J Mugler, Q Chen
PURPOSE: Hyperpolarized xenon-129 dissolved-phase MRI is the first imaging technique that allows 3-dimensional regional mapping of ventilation and gas uptake by tissue and blood the in human lung. Multiple outcome measures can be produced from this method. Existing studies in subjects with major lung diseases compared to healthy controls demonstrated high sensitivities of this method to pulmonary physiological factors including ventilation, alveolar tissue density, surface-to-volume ratio, pulmonary perfusion and gas-blood barrier thickness...
June 2016: Medical Physics
B Tahir, H Marshall, P Hughes, N Stewart, F Horn, G Collier, G Norquay, K Hart, J Swinscoe, M Hatton, J Wild, R Ireland
PURPOSE: To compare the spatial correlation of ventilation surrogates computed from inspiratory and expiratory breath-hold CT with hyperpolarized Helium-3 & Xenon-129 MRI in a cohort of lung cancer patients. METHODS: 5 patients underwent expiration & inspiration breath-hold CT. Xenon-129 & (1) H MRI were also acquired at the same inflation state as inspiratory CT. This was followed immediately by acquisition of Helium-3 & (1) H MRI in the same breath and at the same inflation state as inspiratory CT...
June 2016: Medical Physics
Weiwei Ruan, Jianping Zhong, Yu Guan, Yi Xia, Xiuchao Zhao, Yeqing Han, Xianping Sun, Shiyuan Liu, Chaohui Ye, Xin Zhou
PURPOSE: To demonstrate that hyperpolarized (HP) xenon diffusion kurtosis imaging (DKI) is able to detect smoke-induced pulmonary lesions in rat models. METHODS: Multi-b DKI with hyperpolarized xenon was used for the first time in five smoke-exposed rats and five healthy rats. Additionally, DKI with b values of up to 80 s/cm(2) were used in two healthy rats to probe the critical b value (a limit beyond which the DKI cannot describe the non-Gaussian diffusion). RESULTS: The mean apparent diffusion coefficient (Dapp ) and diffusion kurtosis (Kapp ) extracted by the DKI model revealed significant changes in the smoke-exposed rats compared with those in the control group (P = 0...
November 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Le Zhang, Michael Antonacci, Alex Burant, Karl M Koshlap, Rosa Tamara Branca
A remote detection scheme utilizing the distant dipolar field interaction between two different spin species was proposed by Granwehr et al. [J. Magn. Reson. 176(2), 125 (2005)]. In that sequence (1)H spins were detected indirectly via their dipolar field interaction with (129)Xe spins, which served as the sensing spins. Here we propose a modification of the proposed detection scheme that takes advantage of the longer T1 relaxation time of xenon to create a long lasting dipolar field with which the fast relaxing (1)H spins are allowed to interact many times during a single acquisition...
November 21, 2016: Journal of Chemical Physics
Alex Burant, Rosa Tamara Branca
The production of large volumes of highly polarized noble gases like helium and xenon is vital to applications of magnetic resonance imaging and spectroscopy with hyperpolarized (HP) gas in humans. In the past ten years,129 Xe has become the gas of choice due to its lower cost, higher availability, relatively high tissue solubility, and wide range of chemical shift values. Though near unity levels of xenon polarization have been achieved in-cell using stopped-flow Spin Exchange Optical Pumping (SEOP), these levels are currently unmatched by continuous-flow SEOP methods...
December 2016: Journal of Magnetic Resonance
Le Zhang, Alex Burant, Andrew McCallister, Victor Zhao, Karl M Koshlap, Simone Degan, Michael Antonacci, Rosa Tamara Branca
PURPOSE: To investigate the temperature dependence of the resonance frequency of lipid-dissolved xenon (LDX) and to assess the accuracy of LDX-based MR thermometry. METHODS: The chemical shift temperature dependence of water protons, methylene protons, and LDX was measured from samples containing tissues with varying fat contents using a high-resolution NMR spectrometer. LDX results were then used to acquire relative and absolute temperature maps in vivo and the results were compared with PRF-based MR thermometry...
September 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Tahreema N Matin, Najib Rahman, Annabel H Nickol, Mitchell Chen, Xiaojun Xu, Neil J Stewart, Tom Doel, Vicente Grau, James M Wild, Fergus V Gleeson
Purpose To compare lobar ventilation and apparent diffusion coefficient (ADC) values obtained with hyperpolarized xenon 129 ((129)Xe) magnetic resonance (MR) imaging to quantitative computed tomography (CT) metrics on a lobar basis and pulmonary function test (PFT) results on a whole-lung basis in patients with chronic obstructive pulmonary disease (COPD). Materials and Methods The study was approved by the National Research Ethics Service Committee; written informed consent was obtained from all patients. Twenty-two patients with COPD (Global Initiative for Chronic Obstructive Lung Disease stage II-IV) underwent hyperpolarized (129)Xe MR imaging at 1...
March 2017: Radiology
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