Non-invasive detection and quantification of human foetal brain lactate in utero by magnetic resonance spectroscopy

2010 ◽  
Vol 30 (3) ◽  
pp. 260-266 ◽  
Author(s):  
Geoffrey D. Charles-Edwards ◽  
Wajanat Jan ◽  
Meekai To ◽  
Darryl Maxwell ◽  
Stephen F. Keevil ◽  
...  
2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i2-i2
Author(s):  
Georgios Batsios ◽  
Celine Taglang ◽  
Meryssa Tran ◽  
Anne Marie Gillespie ◽  
Joseph Costello ◽  
...  

Abstract Telomere shortening constitutes a natural barrier to uncontrolled proliferation and all tumors must find a mechanism of maintaining telomere length. Most human tumors, including high-grade primary glioblastomas (GBMs) and low-grade oligodendrogliomas (LGOGs) achieve telomere maintenance via reactivation of the expression of telomerase reverse transcriptase (TERT), which is silenced in normal somatic cells. TERT expression is, therefore, a driver of tumor proliferation and, due to this essential role, TERT is also a therapeutic target. However, non-invasive methods of imaging TERT are lacking. The goal of this study was to identify magnetic resonance spectroscopy (MRS)-detectable metabolic biomarkers of TERT expression that will enable non-invasive visualization of tumor burden in LGOGs and GBMs. First, we silenced TERT expression by RNA interference in patient-derived LGOG (SF10417, BT88) and GBM (GS2) models. Our results linked TERT silencing to significant reductions in steady-state levels of NADH in all models. NADH is essential for the conversion of pyruvate to lactate, suggesting that measuring pyruvate flux to lactate could be useful for imaging TERT status. Recently, deuterium (2H)-MRS has emerged as a novel, clinically translatable method of monitoring metabolic fluxes in vivo. However, to date, studies have solely examined 2H-glucose and the use of [U-2H]pyruvate for non-invasive 2H-MRS has not been tested. Following intravenous injection of a bolus of [U-2H]pyruvate, lactate production was higher in mice bearing orthotopic LGOG (BT88 and SF10417) and GBM (GS2) tumor xenografts relative to tumor-free mice, suggesting that [U-2H]pyruvate has the potential to monitor TERT expression in vivo. In summary, our study, for the first time, shows the feasibility and utility of [U-2H]pyruvate for in vivo imaging. Importantly, since 2H-MRS can be implemented on clinical scanners, our results provide a novel, non-invasive method of integrating information regarding a fundamental cancer hallmark, i.e. TERT, into glioma patient management.


Author(s):  
Jordan David Fliss ◽  
Brandon Zanette ◽  
Yonni Friedlander ◽  
Siddharth Sadanand ◽  
Andras A Lindenmaier ◽  
...  

Premature infants often require mechanical ventilation and oxygen therapy which can result in bronchopulmonary dysplasia (BPD), characterized by developmental arrest and impaired lung function. Conventional clinical methods for assessing the prenatal lung are not adequate for the detection and assessment of long-term health risks in infants with BPD, highlighting the need for a non-invasive tool for the characterization of lung microstructure and function. Theoretical diffusion models, like the Model of Xenon Exchange (MOXE), interrogate alveolar gas exchange by predicting the uptake of inert Hyperpolarized (HP) 129Xe gas measured with HP 129Xe magnetic resonance spectroscopy (MRS). To investigate HP 129Xe MRS as a tool for non-invasive characterization of pulmonary microstructural and functional changes in vivo, HP 129Xe gas exchange data were acquired in an oxygen exposure rat model of BPD that recapitulates the fewer and larger distal airways and pulmonary vascular stunting characteristics of BPD. Gas exchange parameters from MOXE, including airspace mean chord length (L­m), apparent hematocrit in the pulmonary capillaries (HCT), and pulmonary capillary transit time (tx), were compared with airspace mean axis length and area density (MAL and ρ­A) and percentage area of tissue and air (PTA and PAA) from histology. L­m was significantly larger in the exposed rats (p=0.003) and correlated with MAL, ρ­A, PTA, and PAA (0.59<|ρ|<0.66 and p<0.05). Observed increase in HCT (p=0.012) and changes in tx are also discussed. These findings support the use of HP 129Xe MRS for detecting fewer, enlarged distal airways in this rat model of BPD, and potentially in humans.


QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A A Hafez ◽  
M A Nasr ◽  
N L Salman

Abstract Background Exclusion of malignancy in ovarian mass is of paramount importance. It is the most crucial step after identification of a mass and it has a profound effect on the patient's management. So, a reliable method with which to differentiate a benign from a malignant ovarian mass would provide a basis for optimal preoperative planning and may also reduce the number of unnecessary laparotomies for patients undergoing treatment for benign disease. Objective The aim of our study is to highlight the role of magnetic resonance spectroscopy as a non-invasive technique which may effectively assist in differentiating benign from malignant ovarian masses. Patients and Methods This study included 20 patients with adnexal masses as suggested by preliminary pelvic ultrasound examination. referred from the Gynecology Department to the Radiology Department at Ain shams university hospitals. nine were benign, two were borderline, and six were malignant tumors and 3 were hemorrhagic cyst. Endometriosis, tubo-ovarian abscess. Results Our study revealed sharp choline peak in some benign as well as some malignant cases and so Cho peak could not help in the differential diagnosis between benign and malignant tumors, creatine, lipid and NAA were detected in both benign and malignant tumors, also Choline/Creatine Ratio fairly can differentiate between benign and malignant tumors with cut off point = 3.750 at sensitivity = 75.0% & specificity = 100.0% . Conclusion Our study had some factors that affect the results. First, the sample size were not enough to achieve a good results, second, diversity of samples and the complicated tumor histopathologic and morphologic features.


1999 ◽  
Vol 58 (4) ◽  
pp. 861-870 ◽  
Author(s):  
A. Heerschap ◽  
C. Houtman ◽  
H. J. A. in 't Zandt ◽  
A. J. van den Bergh ◽  
B. Wieringa

31P magnetic resonance spectroscopy (MRS) offers a unique non-invasive window on energy metabolism in skeletal muscle, with possibilities for longitudinal studies and of obtaining important bioenergetic data continuously and with sufficient time resolution during muscle exercise. The present paper provides an introductory overview of the current status of in vivo31P MRS of skeletal muscle, focusing on human applications, but with some illustrative examples from studies on transgenic mice. Topics which are described in the present paper are the information content of the 31P magnetic resonance spectrum of skeletal muscle, some practical issues in the performance of this MRS methodology, related muscle biochemistry and the validity of interpreting results in terms of biochemical processes, the possibility of investigating reaction kinetics in vivo and some indications for fibre-type heterogeneity as seen in spectra obtained during exercise.


PEDIATRICS ◽  
2001 ◽  
Vol 107 (2) ◽  
pp. 227-231 ◽  
Author(s):  
L. M. Smith ◽  
L. Chang ◽  
M. L. Yonekura ◽  
K. Gilbride ◽  
J. Kuo ◽  
...  

Cancers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3406
Author(s):  
Elisabeth Bumes ◽  
Fro-Philip Wirtz ◽  
Claudia Fellner ◽  
Jirka Grosse ◽  
Dirk Hellwig ◽  
...  

Isocitrate dehydrogenase (IDH)-1 mutation is an important prognostic factor and a potential therapeutic target in glioma. Immunohistological and molecular diagnosis of IDH mutation status is invasive. To avoid tumor biopsy, dedicated spectroscopic techniques have been proposed to detect D-2-hydroxyglutarate (2-HG), the main metabolite of IDH, directly in vivo. However, these methods are technically challenging and not broadly available. Therefore, we explored the use of machine learning for the non-invasive, inexpensive and fast diagnosis of IDH status in standard 1H-magnetic resonance spectroscopy (1H-MRS). To this end, 30 of 34 consecutive patients with known or suspected glioma WHO grade II-IV were subjected to metabolic positron emission tomography (PET) imaging with O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET) for optimized voxel placement in 1H-MRS. Routine 1H-magnetic resonance (1H-MR) spectra of tumor and contralateral healthy brain regions were acquired on a 3 Tesla magnetic resonance (3T-MR) scanner, prior to surgical tumor resection and molecular analysis of IDH status. Since 2-HG spectral signals were too overlapped for reliable discrimination of IDH mutated (IDHmut) and IDH wild-type (IDHwt) glioma, we used a nested cross-validation approach, whereby we trained a linear support vector machine (SVM) on the complete spectral information of the 1H-MRS data to predict IDH status. Using this approach, we predicted IDH status with an accuracy of 88.2%, a sensitivity of 95.5% (95% CI, 77.2–99.9%) and a specificity of 75.0% (95% CI, 42.9–94.5%), respectively. The area under the curve (AUC) amounted to 0.83. Subsequent ex vivo 1H-nuclear magnetic resonance (1H-NMR) measurements performed on metabolite extracts of resected tumor material (eight specimens) revealed myo-inositol (M-ins) and glycine (Gly) to be the major discriminators of IDH status. We conclude that our approach allows a reliable, non-invasive, fast and cost-effective prediction of IDH status in a standard clinical setting.


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