keyword
MENU ▼
Read by QxMD icon Read
search

Hyperpolarized MRI

keyword
https://www.readbyqxmd.com/read/28517362/the-absence-of-quadrupolar-nuclei-facilitates-efficient-13-c-hyperpolarization-via-reversible-exchange-with-parahydrogen
#1
Danila A Barskiy, Roman V Shchepin, Christian P N Tanner, Johannes F P Colell, Boyd M Goodson, Thomas Theis, Warren S Warren, Eduard Y Chekmenev
Nuclear spin hyperpolarization techniques are revolutionizing the field of (13) C molecular MRI. While dissolution dynamic nuclear polarization (d-DNP) is currently the leading technique, it is generally slow (requiring ≈1 h) and costly (≈$USD10(6) ). As a consequence of carbon's central place in biochemistry, tremendous progress using (13) C d-DNP bioimaging has been demonstrated to date including a number of clinical trials. Despite numerous attempts to develop alternatives to d-DNP, the competing methods have faced significant translational challenges...
May 18, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28514950/lung-function-imaging-methods-in-cystic-fibrosis-pulmonary-disease
#2
REVIEW
Magdalena Kołodziej, Michael J de Veer, Marian Cholewa, Gary F Egan, Bruce R Thompson
Monitoring of pulmonary physiology is fundamental to the clinical management of patients with Cystic Fibrosis. The current standard clinical practise uses spirometry to assess lung function which delivers a clinically relevant functional readout of total lung function, however does not supply any visible or localised information. High Resolution Computed Tomography (HRCT) is a well-established current 'gold standard' method for monitoring lung anatomical changes in Cystic Fibrosis patients. HRCT provides excellent morphological information, however, the X-ray radiation dose can become significant if multiple scans are required to monitor chronic diseases such as cystic fibrosis...
May 17, 2017: Respiratory Research
https://www.readbyqxmd.com/read/28508450/simultaneous-assessment-of-both-lung-morphometry-and-gas-exchange-function-within-a-single-breath-hold-by-hyperpolarized-129-xe-mri
#3
Jianping Zhong, Huiting Zhang, Weiwei Ruan, Junshuai Xie, Haidong Li, He Deng, Yeqing Han, Xianping Sun, Chaohui Ye, Xin Zhou
During the measurement of hyperpolarized (129) Xe magnetic resonance imaging (MRI), the diffusion-weighted imaging (DWI) technique provides valuable information for the assessment of lung morphometry at the alveolar level, whereas the chemical shift saturation recovery (CSSR) technique can evaluate the gas exchange function of the lungs. To date, the two techniques have only been performed during separate breaths. However, the request for multiple breaths increases the cost and scanning time, limiting clinical application...
May 16, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28484627/the-chinchilla-as-a-novel-animal-model-of-pregnancy
#4
Emmeli Mikkelsen, Henrik Lauridsen, Per Mose Nielsen, Haiyun Qi, Thomas Nørlinger, Maria Dahl Andersen, Niels Uldbjerg, Christoffer Laustsen, Puk Sandager, Michael Pedersen
Several parameters are important when choosing the most appropriate animal to model human obstetrics, including gestation period, number of fetuses per gestation and placental structure. The domesticated long-tailed chinchilla (Chinchilla lanigera) is a well-suited and appropriate animal model of pregnancy that often will carry only one offspring and has a long gestation period of 105-115 days. Furthermore, the chinchilla placenta is of the haemomonochorial labyrinthine type and is therefore comparable to the human villous haemomonochorial placenta...
April 2017: Royal Society Open Science
https://www.readbyqxmd.com/read/28473321/hyperpolarized-gas-diffusion-mri-of-biphasic-lung-inflation-in-short-and-long-term-emphysema-models
#5
Yi Xin, Maurizio Cereda, Stephen Kadlecek, Kiarash Emami, Hooman Hamedani, Ian Duncan, Jennia Rajaei, Liam Hughes, Natalie Meeder, Joseph Naji, Harrilla Profka, Brian J Bolognese, Joseph P Foley, Patricia L Podolin, Rahim R Rizi
During lung-inflation, airspace dimensions are affected non-linearly by both alveolar expansion and recruitment, potentially confounding the identification of emphysematous lung by hyperpolarized helium-3 diffusion magnetic resonance imaging (HP MRI). This study aimed to characterize lung inflation over a broad range of inflation volume and pressure values in two different models of emphysema, as well as in normal lungs. Elastase-treated rats (n=7) and healthy controls (n=7) were imaged with HP MRI. Gradual inflation was achieved by incremental changes to both inflation volume and airway pressure...
May 4, 2017: American Journal of Physiology. Lung Cellular and Molecular Physiology
https://www.readbyqxmd.com/read/28451127/cubic-three-dimensional-hybrid-silica-solids-for-nuclear-hyperpolarization
#6
D Baudouin, H A van Kalkeren, A Bornet, B Vuichoud, L Veyre, M Cavaillès, M Schwarzwälder, W-C Liao, D Gajan, G Bodenhausen, L Emsley, A Lesage, S Jannin, C Copéret, C Thieuleux
Hyperpolarization of metabolites by dissolution dynamic nuclear polarization (D-DNP) for MRI applications often requires fast and efficient removal of the radicals (polarizing agents). Ordered mesoporous SBA-15 silica materials containing homogeneously dispersed radicals, referred to as HYperPolarizing SOlids (HYPSOs), enable high polarization - P((1)H) = 50% at 1.2 K - and straightforward separation of the polarizing HYPSO material from the hyperpolarized solution by filtration. However, the one-dimensional tubular pores of SBA-15 type materials are not ideal for nuclear spin diffusion, which may limit efficient polarization...
November 1, 2016: Chemical Science
https://www.readbyqxmd.com/read/28443626/nanodiamond-enhanced-mri-via-in-situ-hyperpolarization
#7
David E J Waddington, Mathieu Sarracanie, Huiliang Zhang, Najat Salameh, David R Glenn, Ewa Rej, Torsten Gaebel, Thomas Boele, Ronald L Walsworth, David J Reilly, Matthew S Rosen
Nanodiamonds are of interest as nontoxic substrates for targeted drug delivery and as highly biostable fluorescent markers for cellular tracking. Beyond optical techniques, however, options for noninvasive imaging of nanodiamonds in vivo are severely limited. Here, we demonstrate that the Overhauser effect, a proton-electron polarization transfer technique, can enable high-contrast magnetic resonance imaging (MRI) of nanodiamonds in water at room temperature and ultra-low magnetic field. The technique transfers spin polarization from paramagnetic impurities at nanodiamond surfaces to (1)H spins in the surrounding water solution, creating MRI contrast on-demand...
April 26, 2017: Nature Communications
https://www.readbyqxmd.com/read/28407455/construction-and-13-c-hyperpolarization-efficiency-of-a-180%C3%A2-ghz-dissolution-dynamic-nuclear-polarization-system
#8
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. In this paper, we report on the development and (13) C hyperpolarization efficiency of a homebuilt 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
#9
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
#10
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
#11
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
#12
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
#13
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 18, 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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
keyword
keyword
85860
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"