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Hyperpolarized MRI

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https://www.readbyqxmd.com/read/28407455/construction-and-13-c-hyperpolarization-efficiency-of-a-180%C3%A2-ghz-dissolution-dynamic-nuclear-polarization-system
#1
Andhika Kiswandhi, Peter Niedbalski, Christopher Parish, Sarah Ferguson, David Taylor, George McDonald, Lloyd Lumata
Dynamic nuclear polarization (DNP) via the dissolution method has become one of the rapidly emerging techniques to alleviate the low signal sensitivity in nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI). In this paper, we report on the development and (13) C hyperpolarization efficiency of a homebuilt dynamic nuclear polarization (DNP) system operating at 6.423 T and 1.4 K. The DNP hyperpolarizer system was assembled on a wide-bore superconducting magnet, equipped with a standard continuous-flow cryostat, and a 180 GHz microwave source with 120 mW power output and wide 4 GHz frequency tuning range...
April 13, 2017: Magnetic Resonance in Chemistry: MRC
https://www.readbyqxmd.com/read/28394085/dual-echo-epi-sequence-for-integrated-distortion-correction-in-3d-time-resolved-hyperpolarized-13-c-mri
#2
Benjamin J Geraghty, Justin Y C Lau, Albert P Chen, Charles H Cunningham
PURPOSE: To provide built-in off-resonance correction in time-resolved, volumetric hyperpolarized (13) C metabolic imaging by implementing a novel dual-echo 3D echo-planar imaging (EPI) sequence and reconstruction. METHODS: A spectral-spatial pulse for single-resonance excitation followed by a dual-echo 3D EPI readout was implemented to provide 64 × 8 × 6 cm(3) coverage at 5 × 5 × 5 mm(3) nominal resolution. Multiple sources of EPI distortions were encoded using a multi-echo (1) H EPI reference scan...
April 10, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28386017/multinuclear-nmr-and-mri-reveal-an-early-metabolic-response-to-mtor-inhibition-in-sarcoma
#3
Valentina Di Gialleonardo, Hannah N Aldeborgh, Vesselin Miloushev, Kelly M Folkers, Kristin Granlund, William D Tap, Jason S Lewis, Wolfgang A Weber, Kayvan Keshari
Biomarkers predicting rapalog responses in sarcomas where PI3K and mTOR are often hyperactivated could improve the suitable recruitment of responsive patients to clinical trials. PI3K/mTOR pathway activation drives energy production by regulating anaerobic glycolysis in cancer cells, suggesting a route toward a monitoring strategy. In this study, we took a multi-modality approach to evaluate the phenotypic effects and metabolic changes which occur with inhibition of the PI3K/mTOR pathway. Its central role in regulating glycolysis in human sarcomas was evaluated by short- and long-term rapamycin treatment in sarcoma cell lines...
April 6, 2017: Cancer Research
https://www.readbyqxmd.com/read/28384123/magnetic-resonance-imaging-with-hyperpolarized-agents-methods-and-applications
#4
Erin Adamson, Kai Ludwig, David 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 (<sup>3</sup>He) and xenon (<sup>129</sup>Xe) gases have reached the stage where they are under study in clinical research. HP <sup>129</sup>Xe, in particular, is poised for larger scale clinical research to investigate asthma, chronic obstructive pulmonary disease, and fibrotic lung diseases...
April 6, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28382694/quantitative-analysis-of-hyperpolarized-129-xe-gas-transfer-mri
#5
Ziyi Wang, Scott Haile Robertson, Jennifer Wang, Mu He, Rohan S Virgincar, Geoffry M Schrank, Elianna A Bier, Sudarshan Rajagopal, Yuh Chin Huang, Thomas G O'Riordan, Craig R Rackley, H Page McAdams, Bastiaan Driehuys
PURPOSE: Hyperpolarized (129) Xe magnetic resonance imaging (MRI) using Dixon-based decomposition enables single-breath imaging of (129) Xe in the airspaces, interstitial barrier tissues, and red blood cells (RBCs). However, methods to quantitatively visualize information from these images of pulmonary gas transfer are lacking. Here, we introduce a novel method to transform these data into quantitative maps of pulmonary ventilation, and (129) Xe gas transfer to barrier and RBC compartments...
April 6, 2017: Medical Physics
https://www.readbyqxmd.com/read/28377523/delivering-strong-1-h-nuclear-hyperpolarization-levels-and-long-magnetic-lifetimes-through-signal-amplification-by-reversible-exchange
#6
Peter J Rayner, Michael J Burns, Alexandra M Olaru, Philip Norcott, Marianna Fekete, Gary G R Green, Louise A R Highton, Ryan E Mewis, Simon B Duckett
Hyperpolarization turns typically weak NMR and MRI responses into strong signals so that ordinarily impractical measurements become possible. The potential to revolutionize analytical NMR and clinical diagnosis through this approach reflect this area's most compelling outcomes. Methods to optimize the low-cost parahydrogen-based approach signal amplification by reversible exchange with studies on a series of biologically relevant nicotinamides and methyl nicotinates are detailed. These procedures involve specific (2)H labeling in both the agent and catalyst and achieve polarization lifetimes of ca 2 min with 50% polarization in the case of methyl-4,6-d2 -nicotinate...
April 4, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28371091/novel-magnetic-resonance-imaging-for-assessment-of-bronchial-stenosis-in-lung-transplant-recipients
#7
Kamran Mahmood, Lukas Ebner, Mu He, Scott Haile Robertson, Ziyi Wang, H Page McAdams, Momen M Wahidi, Scott L Shofer, Yuh-Chin T Huang, Bastiaan Driehuys
Bronchial stenosis in lung transplant recipients is a common disorder that adversely affects clinical outcomes. It is evaluated by spirometry, CT scan and bronchoscopy with significant limitations. We hypothesize that magnetic resonance imaging (MRI) employing both ultrashort echo time (UTE) scans and hyperpolarized (HP) (129) Xe gas can offer structural and functional assessment of bronchial stenosis seen after lung transplantation. Six patients with lung transplantation-related bronchial stenosis underwent HP (129) Xe MRI and UTE MRI...
March 29, 2017: American Journal of Transplantation
https://www.readbyqxmd.com/read/28365086/synthesis-and-hyperpolarisation-of-enos-substrates-for-quantification-of-no-production-by-1-h-nmr-spectroscopy
#8
Fernando Fernandez Diaz-Rullo, Francesco Zamberlan, Ryan E Mewis, Marianna Fekete, Lionel Broche, Lesley A Cheyne, Sergio Dall'Angelo, Simon B Duckett, Dana Dawson, Matteo Zanda
Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of l-arginine into l-citrulline. NO is a free radical gas with a short half-life in vivo (≈5s), therefore direct NO quantification is challenging...
May 15, 2017: Bioorganic & Medicinal Chemistry
https://www.readbyqxmd.com/read/28336821/hyperbaric-oxygen-therapy-reduces-renal-lactate-production
#9
Thomas S Nørlinger, Per Mose Nielsen, Haiyun Qi, Emmeli Mikkelsen, Kasper Hansen, Nikolaj H Schmidt, Michael Pedersen, Peter Agger, Fredrik Palm, Christoffer Laustsen
Intrarenal hypoxia is an acknowledged factor contributing to the development of diabetic nephropathy. Hyperbaric oxygen (HBO) therapy is a well-known adjuvant treatment for several medical conditions, such as decompression sickness, infections, and wound healing. The underlying metabolic response of HBO is largely unknown. In this study, we investigated the effect of HBO on the intrarenal metabolic alteration in diabetes. Hyperpolarized [1-(13)C]pyruvate MRI was performed to assess intrarenal energy metabolism in normoglycemic controls and short-term (2 weeks) streptozotocin-induced diabetic rats with and without HBO for five consecutive days...
March 2017: Physiological Reports
https://www.readbyqxmd.com/read/28290535/continuous-flow-dnp-polarizer-for-mri-applications-at-1-5%C3%A2-t
#10
V Denysenkov, M Terekhov, R Maeder, S Fischer, S Zangos, T Vogl, T F Prisner
Here we describe a new hyperpolarization approach for magnetic resonance imaging applications at 1.5 T. Proton signal enhancements of more than 20 were achieved with a newly designed multimode microwave resonator situated inside the bore of the imager and used for Overhauser dynamic nuclear polarization of the water proton signal. Different from other approaches in our setup the hyperpolarization is achieved continuously by liquid water flowing through the polarizer under continuous microwave excitation. With an available flow rate of up to 1...
March 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28272754/hyperpolarized-%C3%AE-1-13-c-gluconolactone-as-a-probe-of-the-pentose-phosphate-pathway
#11
Karlos X Moreno, Crystal E Harrison, Matthew E Merritt, Zoltan Kovacs, Craig R Malloy, A Dean Sherry
The pentose phosphate pathway (PPP) is thought to be upregulated in trauma (to produce excess NADPH) and in cancer (to provide ribose for nucleotide biosynthesis), but simple methods for detecting changes in flux through this pathway are not available. MRI of hyperpolarized (13) C-enriched metabolites offers considerable potential as a rapid, non-invasive tool for detecting changes in metabolic fluxes. In this study, hyperpolarized δ-[1-(13) C]gluconolactone was used as a probe to detect flux through the oxidative portion of the pentose phosphate pathway (PPPox ) in isolated perfused mouse livers...
March 8, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28266629/an-optimized-microfabricated-platform-for-the-optical-generation-and-detection-of-hyperpolarized-129-xe
#12
Daniel J Kennedy, Scott J Seltzer, Ricardo Jiménez-Martínez, Hattie L Ring, Nicolas S Malecek, Svenja Knappe, Elizabeth A Donley, John Kitching, Vikram S Bajaj, Alexander Pines
Low thermal-equilibrium nuclear spin polarizations and the need for sophisticated instrumentation render conventional nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) incompatible with small-scale microfluidic devices. Hyperpolarized (129)Xe gas has found use in the study of many materials but has required very large and expensive instrumentation. Recently a microfabricated device with modest instrumentation demonstrated all-optical hyperpolarization and detection of (129)Xe gas. This device was limited by (129)Xe polarizations less than 1%, (129)Xe NMR signals smaller than 20 nT, and transport of hyperpolarized (129)Xe over millimeter lengths...
March 7, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28262691/liquid-state-carbon-13-hyperpolarization-generated-in-an-mri-system-for-fast-imaging
#13
A B Schmidt, S Berner, W Schimpf, C Müller, T Lickert, N Schwaderlapp, S Knecht, J G Skinner, A Dost, P Rovedo, J Hennig, D von Elverfeldt, J-B Hövener
Hyperpolarized (HP) tracers dramatically increase the sensitivity of magnetic resonance imaging (MRI) to monitor metabolism non-invasively and in vivo. Their production, however, requires an extra polarizing device (polarizer) whose complexity, operation and cost can exceed that of an MRI system itself. Furthermore, the lifetime of HP tracers is short and some of the enhancement is lost during transfer to the application site. Here, we present the production of HP tracers in water without an external polarizer: by Synthesis Amid the Magnet Bore, A Dramatically Enhanced Nuclear Alignment (SAMBADENA) is achieved within seconds, corresponding to a hyperpolarization of ∼20%...
March 6, 2017: Nature Communications
https://www.readbyqxmd.com/read/28247437/hyperpolarized-129xe-mri-sensor-for-h2s
#14
Shengjun Yang, Yaping Yuan, Weiping Jiang, Lili Ren, He Deng, Louis-S Bouchard, Xin Zhou, Maili Liu
A new MRI molecular sensor for hydrogen sulfide detection and imaging using the nuclear spin resonance of hyperpolarized 129Xe 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 fluorescent H2S 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
https://www.readbyqxmd.com/read/28237893/dynamic-nuclear-polarization-via-thermal-mixing-beyond-the-high-temperature-approximation
#15
W Th Wenckebach
Dynamic Nuclear Polarization (DNP) via the mechanism of thermal mixing has proven itself most powerful for the orientation of nuclear spins in polarized targets and hyperpolarization for magnetic resonance imaging (MRI). Unfortunately, theoretical descriptions of this mechanism have been limited to using-at least partially-the high temperature approximation, in which Boltzmann factors are expanded linearly. However, the high nuclear spin polarization required and obtained for these applications does not justify such approximations...
February 20, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28152435/nmr-spin-lock-induced-crossing-slic-dispersion-and-long-lived-spin-states-of-gaseous-propane-at-low-magnetic-field-0-05t
#16
Danila A Barskiy, Oleg G Salnikov, Alexey S Romanov, Matthew A Feldman, Aaron M Coffey, Kirill V Kovtunov, Igor V Koptyug, Eduard Y Chekmenev
When parahydrogen reacts with propylene in low magnetic fields (e.g., 0.05T), the reaction product propane develops an overpopulation of pseudo-singlet nuclear spin states. We studied how the Spin-Lock Induced Crossing (SLIC) technique can be used to convert these pseudo-singlet spin states of hyperpolarized gaseous propane into observable magnetization and to detect (1)H NMR signal directly at 0.05T. The theoretical simulation and experimental study of the NMR signal dependence on B1 power (SLIC amplitude) exhibits a well-resolved dispersion, which is induced by the spin-spin couplings in the eight-proton spin system of propane...
March 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28132845/use-of-hyperpolarized-helium-3-mri-to-assess-response-to-ivacaftor-treatment-in-patients-with-cystic-fibrosis
#17
Talissa A Altes, Mac Johnson, Meredith Fidler, Martyn Botfield, Nicholas J Tustison, Carlos Leiva-Salinas, Eduard E de Lange, Deborah Froh, John P Mugler
BACKGROUND: This pilot study evaluated the effect of short- and long-term ivacaftor treatment on hyperpolarized (3)He-magnetic resonance imaging (MRI)-defined ventilation defects in patients with cystic fibrosis aged ≥12years with a G551D-CFTR mutation. METHODS: Part A (single-blind) comprised 4weeks of ivacaftor treatment; Part B (open-label) comprised 48weeks of treatment. The primary outcome was change from baseline in total ventilation defect (TVD; total defect volume:total lung volume ratio)...
March 2017: Journal of Cystic Fibrosis: Official Journal of the European Cystic Fibrosis Society
https://www.readbyqxmd.com/read/28120553/what-makes-a-good-pediatric-transplant-lung-insights-from-in-vivo-lung-morphometry-with-hyperpolarized-3-he-magnetic-resonance-imaging
#18
Emily F Fishman, James D Quirk, Stuart C Sweet, Jason C Woods, David S Gierada, Mark S Conradi, Marilyn J Siegel, Dmitriy A Yablonskiy
Obtaining information on transplanted lung microstructure is an important part of the current care for monitoring transplant recipients. However, until now this information was only available from invasive lung biopsy. The objective of this study was to evaluate the use of an innovative non-invasive technique, in vivo lung morphometry with hyperpolarized ³He MRI-to characterize lung microstructure in the pediatric lung transplant population. This technique yields quantitative measurements of acinar airways' (alveolar ducts and sacs) parameters, such as acinar airway radii and alveolar depth...
May 2017: Pediatric Transplantation
https://www.readbyqxmd.com/read/28112867/high-spatial-resolution-hyperpolarized-3-he-mri-of-the-rodent-lung-using-a-single-breath-x-centric-gradient-recalled-echo-approach
#19
Alexei V Ouriadov, Giles E Santyr
PURPOSE: Hyperpolarized (HP) gas MRI of the rodent lung is of great interest because of the increasing need for novel biomarkers with which to develop new therapies for respiratory diseases. The use of fast gradient-recalled echo (FGRE) for high-resolution HP gas rodent lung MRI is challenging as a result of signal loss caused by significant diffusion weighting, particularly in the larger airways. In this work, a modified FGRE approach is described for HP (3) He rodent lung MRI using a centric-out readout scheme (ie, x-centric), allowing high-resolution, density-weighted imaging...
January 23, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28106110/in-vivo-detection-of-cucurbit-6-uril-a-hyperpolarized-xenon-contrast-agent-for-a-xenon-magnetic-resonance-imaging-biosensor
#20
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
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