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NMR in Biomedicine

Timothy L Kline, Caroline R Sussman, Maria V Irazabal, Prasanna K Mishra, Elisabeth A Pearson, Vicente E Torres, Slobodan I Macura
While zebrafish embryos in the first five days after fertilization are clear and amenable to optical analysis, older juveniles and adults are not, due to pigmentation development and tissue growth. Thus other imaging methods are needed to image adult specimens. NMR is a versatile tool for studies of biological systems and has been successfully used for in vivo zebrafish microscopy. In this work we use NMR microscopy (MRM) for assessment of zebrafish specimens, which includes imaging of formalin fixed (FF), formalin fixed and paraffin embedded (FFPE), fresh (unfixed), and FF gadolinium doped specimens...
November 15, 2018: NMR in Biomedicine
Jan Heidkamp, Petra L M Zusterzeel, Adriana C H van Engen-van Grunsven, Christiaan G Overduin, Andor Veltien, Arie Maat, Maroeska M Rovers, Jurgen J Fütterer
In the surgical treatment of vulvar squamous-cell carcinoma (VSCC), tumor-free margins of 8 mm or more are considered adequate. However, limited perioperative information on the tumor-free margins other than the surgeon's own estimation is available. The purpose of this study was therefore to investigate the feasibility of ex vivo MRI in localizing VSCC and to assess the surgical tumor-free margins in fresh radical local excision (RLE) specimens to guide the surgeon during resections. Nine patients with biopsy-proven VSCC scheduled for RLE were prospectively included...
November 15, 2018: NMR in Biomedicine
Haiyun Qi, Christian Østergaard Mariager, Per Mose Nielsen, Marie Schroeder, Jakob Lindhardt, Rikke Nørregaard, Janet D Klein, Jeff M Sands, Christoffer Laustsen
Renal urea handling is central to the urine concentrating mechanism, and as such the ability to image urea transport in the kidney is an important potential imaging biomarker for renal functional assessment. Glucagon levels associated with changes in dietary protein intake have been shown to influence renal urea handling; however, the exact mechanism has still to be fully understood. Here we investigate renal function and osmolite distribution using [13 C,15 N] urea dynamics and 23 Na distribution before and 60 min after glucagon infusion in six female rats...
November 14, 2018: NMR in Biomedicine
Nikola Cesarovic, Julia Busch, Miriam Lipiski, Maximilian Fuetterer, Thea Fleischmann, Silvia Born, Constantin von Deuster, Mareike Sauer, Francesco Maisano, Sebastian Kozerke, Christian T Stoeck
Intracardiac blood flow patterns are affected by the morphology of cardiac structures and are set up to support the heart's pump function. Exercise affects contractility and chamber size as well as pre- and afterload. The aim of this study was to test the feasibility of four-dimensional phase contrast cardiovascular MRI under pharmacological stress and to study left ventricular blood flow under stress. 4D flow data were successfully acquired and analysed in 12 animals. During dobutamine infusion, heart rate and ejection fraction increased (82 ± 5 bpm versus 124 ± 3 bpm/46 ± 9% versus 65 ± 7%; both p < 0...
November 7, 2018: NMR in Biomedicine
Marianna Inglese, Carlo Cavaliere, Serena Monti, Ernesto Forte, Mariarosaria Incoronato, Emanuele Nicolai, Marco Salvatore, Marco Aiello
46 patients with histologically confirmed breast cancer were enrolled and imaged with a 3T hybrid PET/MRI system, at staging. Diffusion, functional and perfusion parameters (measured by Tofts and shutter speed models) were compared. Results showed a good correlation between pharmacokinetic parameters and the SUV.
October 31, 2018: NMR in Biomedicine
Elisenda Bonet-Carne, Edward Johnston, Alessandro Daducci, Joseph G Jacobs, Alex Freeman, David Atkinson, David J Hawkes, Shonit Punwani, Daniel C Alexander, Eleftheria Panagiotaki
VERDICT (vascular, extracellular and restricted diffusion for cytometry in tumours) estimates and maps microstructural features of cancerous tissue non-invasively using diffusion MRI. The main purpose of this study is to address the high computational time of microstructural model fitting for prostate diagnosis, while retaining utility in terms of tumour conspicuity and repeatability. In this work, we adapt the accelerated microstructure imaging via convex optimization (AMICO) framework to linearize the estimation of VERDICT parameters for the prostate gland...
October 31, 2018: NMR in Biomedicine
Hui Zhang, Yijuan Zou, Hao Lei
Many neurological/psychiatric disorders are associated with metabolic abnormalities in the brain observable with in vivo proton MRS (1 H-MRS). The underlying molecular/cellular mechanisms and functional correlations of such metabolic alterations, however, are yet to be understood fully. The rodent prefrontal cortex (PFC) is comprised of multiple sub-regions with distinctive cytoarchitecture and functions, providing a good model system to study the correlations among cerebral metabolism, regional cytoarchitecture and connectivity...
October 30, 2018: NMR in Biomedicine
Logan Fairgrieve-Park, Clara J Fallone, Atiyah Yahya
The glycerol methylene proton resonances (4-4.5 parts per million, ppm), which arise from the triglyceride backbone, are relevant to fat composition assessment and can be measured with proton MRS. The purpose of the presented work is to determine long TE (echo time) point resolved spectroscopy (PRESS) and stimulated echo acquisition mode (STEAM) values at 3 T to resolve the glycerol resonances from that of overlapping water. The response of the glycerol methylene protons of nine edible oils as a function of PRESS and STEAM TE (mixing time, TM = 20 ms) was investigated...
October 30, 2018: NMR in Biomedicine
C S Arteaga de Castro, J P Hoogendam, I M L van Kalleveen, A J E Raaijmakers, R P Zweemer, R H M Verheijen, P R Luijten, W B Veldhuis, D W J Klomp
The differentiation grade of cervical cancer is histologically assessed by examining biopsies or surgical specimens. MRS is a highly sensitive technique that images tissue metabolism and can be used to increase the specificity of tissue characterization in a non-invasive manner. We aim to explore the feasibility of using in vivo 1 H-MRS at 7 T in women with cervical cancer to study tissue fatty acid composition. 10 women with histologically proven Stage IB1-IIB cervical cancer were scanned with a whole-body 7 T MR system with a multi-transmit system and an internal receive only monopole antenna...
October 30, 2018: NMR in Biomedicine
Rossella Canese, Gianmauro Palombelli, Mattea Chirico, Paola Sestili, Marina Bagnoli, Silvana Canevari, Delia Mezzanzanica, Franca Podo, Egidio Iorio
Although several drugs are available to treat recurrences of human epithelial ovarian cancer (EOC), clinical responses often remain short lived and lead to only marginal improvements in patients' survival. One of the new drugs proposed for recurrent platinum-resistant EOC patients is trabectedin (Trab), a marine-derived antitumor agent initially isolated from the tunicate Ecteinascidia turbinata and currently produced synthetically. Predictive biomarkers of therapy response to this drug and the potential use of non-invasive functional MRI and MRS approaches for an early assessment of Trab efficacy have not yet been evaluated, although they might be relevant for improving the clinical management of EOC patients...
October 30, 2018: NMR in Biomedicine
Zhongliang Zu
Recently, a new nuclear Overhauser enhancement (NOE)-mediated saturation transfer effect at around -1.6 ppm from water, termed NOE(-1.6), was reported to show hypointense signals in brain tumors. Similar to chemical exchange saturation transfer or magnetization transfer (MT) effects, which depend on the solute pool concentration, the exchange/coupling rate, the solute transverse relaxation rate, etc., the NOE(-1.6) effect should also depend on these factors. Since the exchange rate is relevant to tissue pH, and the coupling rate and the solute transverse relaxation rate are relevant to the motional property of the coupled molecules, further studies to quantify the contribution from only the exchange/coupling rate and the solute transverse relaxation rate are always interesting...
October 18, 2018: NMR in Biomedicine
Sahar Nassirpour, Paul Chang, Thomas Kirchner, Anke Henning
The aim of this work was to use post-processing methods to improve the data quality of metabolite maps acquired on the human brain at 9.4 T with accelerated acquisition schemes. This was accomplished by combining an improved sensitivity encoding (SENSE) reconstruction with a B0 correction of spatially over-discretized magnetic resonance spectroscopic imaging (MRSI) data. Since MRSI scans suffer from long scan duration, investigating different acceleration techniques has recently been the focus of several studies...
October 18, 2018: NMR in Biomedicine
Christina Precht, Gaëlle Diserens, Martina Vermathen, Anna Oevermann, Josiane Lauper, Peter Vermathen
Listeria rhombencephalitis is caused by infection with Listeria monocytogenes and is associated with a high mortality rate in humans and ruminants. Little is known about the metabolic changes associated with neurolisteriosis in particular and infectious central nervous system (CNS) diseases in general. The purpose of our study was to investigate the metabolic changes associated with listeria rhombencephalitis in small ruminants (goats and sheep) as a model for inflammatory CNS disease by 1 H high-resolution magic angle spinning nuclear magnetic resonance (1 H HR-MAS NMR) spectroscopy of brain biopsies obtained from the brainstem and thalamus...
October 17, 2018: NMR in Biomedicine
Dmitry S Novikov, Els Fieremans, Sune N Jespersen, Valerij G Kiselev
We review, systematize and discuss models of diffusion in neuronal tissue, by putting them into an overarching physical context of coarse-graining over an increasing diffusion length scale. From this perspective, we view research on quantifying brain microstructure as occurring along three major avenues. The first avenue focusses on transient, or time-dependent, effects in diffusion. These effects signify the gradual coarse-graining of tissue structure, which occurs qualitatively differently in different brain tissue compartments...
October 15, 2018: NMR in Biomedicine
Rachelle Crescenzi, Paula M Donahue, Vaughn G Braxton, Allison O Scott, Helen B Mahany, Sarah K Lants, Manus J Donahue
The purpose of this work was to quantify 3.0 T (i) T1 and T2 relaxation times of in vivo human lymph nodes (LNs) and (ii) LN relaxometry differences between healthy LNs and LNs from patients with lymphatic insufficiency secondary to breast cancer treatment-related lymphedema (BCRL). MR relaxometry was performed over bilateral axillary regions at 3.0 T in healthy female controls (105 LNs from 20 participants) and patients with BCRL (108 LNs from 20 participants). Quantitative T1 maps were calculated using a multi-flip-angle (20, 40, 60°) method with B1 correction (dual-TR method, TR1 /TR2  = 30/130 ms), and T2 maps using a multi-echo (TE  = 9-189 ms; 12 ms intervals) method...
October 12, 2018: NMR in Biomedicine
Wybe J M van der Kemp, Tijl A van der Velden, Alexander M Schmitz, Kenneth G Gilhuijs, Peter R Luijten, Dennis W J Klomp, Jannie P Wijnen
Phosphorus MRS offers a non-invasive tool for monitoring cell energy and phospholipid metabolism and can be of additional value in diagnosing cancer and monitoring cancer therapy. In this study, we determined the transverse relaxation times of a number of phosphorous metabolites in a group of breast cancer patients by adiabatic multi-echo spectroscopic imaging at 7 T. The transverse relaxation times of phosphoethanolamine, phosphocholine, inorganic phosphate (Pi ), glycerophosphocholine and glycerophosphatidylcholine were 184 ± 8 ms, 203 ± 17 ms, 87 ± 8 ms, 240 ± 56 ms and 20 ± 10 ms, respectively...
October 12, 2018: NMR in Biomedicine
Hongchen Wang, Catherine Sebrié, Sébastien Judé, Anne Maurin, Stéphanie Rétif, Marilyne Le Mée, Felicia Julea, Rose-Marie Dubuisson, Georges Willoquet, Khaoula Bouazizi, Luc Darrasse, Geneviève Guillot, Xavier Maître, Ludovic de Rochefort
Asthma is a chronic respiratory disease, commonly treated with inhaled therapy. Better understanding of the mechanisms of aerosol deposition is required to improve inhaled drug delivery. Three-dimensional ultrashort echo time (UTE) MRI acquisitions at 1.5 T were combined with spontaneous nose-only inhalation of aerosolized gadolinium (Gd) to map the aerosol deposition and to characterize signal enhancement in asthmatic rat lungs. The rats were sensitized to ovalbumin (OVA) to develop asthmatic models and challenged before imaging by nebulization of OVA to trigger asthmatic symptoms...
October 11, 2018: NMR in Biomedicine
Grégory Kuchcinski, Florent Auger, Clémence Leboullenger, Romain Viard, Renaud Lopes
No abstract text is available yet for this article.
October 11, 2018: NMR in Biomedicine
Lena V Gast, Teresa Gerhalter, Bernhard Hensel, Michael Uder, Armin M Nagel
Double quantum filtered 23 Na MRI with magic angle excitation (DQF-MA) can be used to selectively detect sodium ions located within anisotropic structures such as muscle fibers. It might therefore be a promising tool to analyze the microscopic environment of sodium ions, for example in the context of osmotically neutral sodium retention. However, DQF-MA imaging is challenging due to various signal dependences, on both measurement parameters and external influences. The aim of this work was to examine how B0 in combination with B1 inhomogeneities alter the DQF-MA signal intensity...
October 5, 2018: NMR in Biomedicine
Małgorzata Marjańska, Alexander A Shestov, Dinesh K Deelchand, Emily Kittelson, Pierre-Gilles Henry
Carbon-13 NMR spectroscopy (13 C MRS) offers the unique capability to measure brain metabolic rates in vivo. Hyperpolarized 13 C reduces the time required to assess brain metabolism from hours to minutes when compared with conventional 13 C MRS. This study investigates metabolism of hyperpolarized [1-13 C]pyruvate and [2-13 C]pyruvate in the rat brain in vivo under various anesthetics: pentobarbital, isoflurane, α-chloralose, and morphine. The apparent metabolic rate from pyruvate to lactate modeled using time courses obtained after injection of hyperpolarized [1-13 C]pyruvate was significantly greater for isoflurane than for all other anesthetic conditions, and significantly greater for morphine than for α-chloralose...
October 1, 2018: NMR in Biomedicine
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