A5065022341- Advanced NMR Techniques and Applications
- Advanced MRI Techniques and Applications
- Electron Spin Resonance Studies
- Atomic and Subatomic Physics Research
- Solid-state spectroscopy and crystallography
- Alcoholism and Thiamine Deficiency
- Infectious Encephalopathies and Encephalitis
- Neuroscience and Neuropharmacology Research
- Ultrasound and Hyperthermia Applications
- Advanced Neuroimaging Techniques and Applications
- bioluminescence and chemiluminescence research
- Medical Imaging Techniques and Applications
- Functional Brain Connectivity Studies
- Neurological and metabolic disorders
- Lung Cancer Diagnosis and Treatment
- NMR spectroscopy and applications
- Metabolomics and Mass Spectrometry Studies
- Enzyme Structure and Function
- Medical Image Segmentation Techniques
- Cancer, Hypoxia, and Metabolism
- Virus-based gene therapy research
- Neurotransmitter Receptor Influence on Behavior
- Liver Disease Diagnosis and Treatment
- Radiomics and Machine Learning in Medical Imaging
- Heat shock proteins research
University of Maryland, Baltimore
2015-2025
U-M Rogel Cancer Center
2018-2024
Advanced Imaging Research (United States)
2024
University of Maryland, College Park
2021-2023
SRI International
2008-2021
University of Maryland Medical Center
2017-2021
Klinikum Coburg
2008-2020
University of Split
2020
Stanford University
2006-2015
Menlo School
2008-2015
Oesophageal injury has been reported with delivery of radio-frequency lesions at the left atrium posterior wall in catheter ablation procedures for atrial fibrillation (AF). In this observational study we prospectively assessed endoscopical oesophageal changes after pulmonary vein antrum isolation (PVAI) patients presenting treatment AF. Twenty eight (18 men; mean age 55 ± 11 years) were ablated using either a cooled-tip or an 8 mm tip catheter. Endoscopy oesophagus was performed 24 h PVAI....
Abstract MRI with hyperpolarized (HP) 13 C agents, also known as HP MRI, can measure processes such localized metabolism that is altered in numerous cancers, liver, heart, kidney diseases, and more. It has been translated into human studies during the past 10 years, recent rapid growth largely based on increasing availability of agent preparation methods suitable for use humans. This paper aims to capture current successful practices [1‐ C]pyruvate—by far most commonly used agent, which sits...
Abstract Formulation, polarization, and dissolution conditions were developed to obtain a stable hyperpolarized solution of [1‐ 13 C]‐ethyl pyruvate. A maximum tolerated concentration injection rate determined, C spectroscopic imaging was used compare the uptake pyruvate relative C]‐pyruvate into anesthetized rat brain. Hyperpolarized metabolic in normal brain is demonstrated quantified this feasibility range‐finding study. Magn Reson Med 63:1137–1143, 2010. © 2010 Wiley‐Liss, Inc.
Abstract Purpose: To determine if magnetotactic bacteria can target tumors in mice and provide positive contrast for visualization using magnetic resonance imaging. Experimental Design: The ability of the bacterium, Magnetospirillum magneticum AMB-1 (referred to from here as AMB-1), confer imaging was determined vitro vivo. For latter studies, were injected either i.t. or i.v. Bacterial growth conditions manipulated produce small (∼25-nm diameter) magnetite particles, which observed...
Traumatic brain injury (TBI) is known to cause perturbations in the energy metabolism of brain, but current tests metabolic activity are only indirect markers use or highly invasive. Here we show that hyperpolarized 13C magnetic resonance spectroscopic imaging (MRSI) can be used as a direct, non-invasive method for studying effects TBI on metabolism. Measurements were performed rats with moderate induced by controlled cortical impact one cerebral hemisphere. Following injection...
Abstract Dynamic nuclear polarization can create hyperpolarized compounds with MR signal‐to‐noise ratio enhancements on the order of 10,000‐fold. Both exogenous and normally occurring endogenous be polarized, their initial concentration downstream metabolic products assessed using spectroscopy. Given transient nature signal enhancement, fast imaging techniques are a critical requirement for real‐time imaging. We report development an ultrafast, multislice, spiral chemical shift sequence,...
Glutamate (Glu), the principal excitatory neurotransmitter of prefrontal cortical efferents, potentially mediates higher order cognitive processes, and its altered availability may underlie mechanisms age-related decline in frontally based functions. Although animal studies support a role for Glu deterioration, human studies, which require magnetic resonance spectroscopy vivo measurement this neurotransmitter, have been impeded because similarity Glu's spectroscopic signature to those...
A single-voxel Carr-Purcell-Meibloom-Gill sequence was developed to measure localized T2 relaxation times of 13C-labeled metabolites in vivo for the first time. Following hyperpolarized [1-13C]pyruvate injections, pyruvate and its metabolic products, alanine lactate, were observed liver five rats with hepatocellular carcinoma healthy control rats. The lactate both significantly longer HCC tumors than normal livers (p < 0.002). also showed higher signal relative total 13C 0.006). intra-...
Hyperpolarized [1‐ 13 C]pyruvate ([1‐ C]Pyr) has been used to assess metabolism in healthy and diseased states, focusing on the downstream labeling of lactate (Lac), bicarbonate alanine. Although hyperpolarized [2‐ C]Pyr, which retains labeled carbon when Pyr is converted acetyl‐coenzyme A, successfully mitochondrial heart, application C]Pyr study brain limited date, with Lac being only metabolic product reported previously. In this study, single‐time‐point chemical shift imaging data were...
The metabolic phenotype that derives disproportionate energy via glycolysis in solid tumors, including glioma, leads to elevated lactate labeling imaging using hyperpolarized [1-13C]pyruvate. Although the pyruvate dehydrogenase (PDH)–mediated flux from acetyl coenzyme A can be indirectly measured through detection of carbon-13 (13C)-labeled bicarbonate, it has proven difficult visualize 13C-bicarbonate at high enough levels injected [1-13C]pyruvate for quantitative analysis brain. aim this...
Abstract Neuroinflammatory mechanisms contribute to the brain pathology resulting from human immunodeficiency virus ( HIV ) infection. Magnetic resonance spectroscopy MRS has been touted as a suitable method for discriminating in vivo markers of neuroinflammation. The present study was conducted four groups: alcohol dependent A , n = 37), ‐infected H 33), + infected HA 38) and healthy control C 62) individuals determine whether metabolites would change pattern reflecting Significant...
To facilitate diagnosis and staging of liver disease, sensitive non-invasive methods for the measurement metabolism are needed. This study used hyperpolarized 13C-pyruvate to assess metabolic parameters in a CCl4 model damage rats. Dynamic 3D 13C chemical shift imaging data from volume covering kidney were acquired 8 control 10 CCl4-treated At 12 time points at 5 s temporal resolution, we quantified signal intensities established courses pyruvate, alanine, lactate. These measurements...
Hyperpolarized [1‐ 13 C]pyruvate MRS provides a unique imaging opportunity to study the reaction kinetics and enzyme activities of in vivo metabolism because its favorable characteristics critical position cellular metabolic pathway, where it can either be reduced lactate (reflecting glycolysis) or converted acetyl‐coenzyme A bicarbonate oxidative phosphorylation). Cancer tissue is altered such way as result relative preponderance glycolysis phosphorylation (i.e. Warburg effect). Although...
Abstract Overconsumption of added sugars such as fructose has been associated with a remarkable decline in metabolic health. Fructose is primarily metabolized by the small intestines and liver, via phosphorylation mediated ketohexokinase (KHK). KHK activity traditionally viewed lacking negative feedback mechanisms, those present to limit glucose metabolism, leading excessive fat accumulation characteristic dysfunction-associated liver disease (MASLD). In this study, we observe downregulation...
Abstract A fast spiral chemical shift imaging (spCSI) sequence was developed for application to hyperpolarized 13 C imaging. The exploits sparse spectra, which can occur in such applications, and prior knowledge of resonance frequencies reduce the measurement time by undersampling data spectral domain. As a consequence, multiple reconstructions given set have be computed only components with within certain bandwidth are reconstructed “in focus” while others severely blurred (“spectral...
A least-squares-based optimization and reconstruction algorithm has been developed for rapid metabolic imaging in the context of hyperpolarized (13)C. The uses a priori knowledge resonance frequencies, J-coupling constants, T(2)* values to enable acquisition high-quality images with times approximately 100 ms an 8-cm field view (FOV) 0.5 cm isotropic resolution. root-mean-square error (rMSE) analysis is introduced optimize image quality by appropriate choice pulse sequence parameters, echo...
Abstract [1‐ 13 C]Pyruvate is a readily polarizable substrate that has been the subject of numerous magnetic resonance spectroscopy (MRS) studies in vivo metabolism. In this work C‐MRS hyperpolarized C]pyruvate was used to interrogate metabolic pathway involved neither aerobic nor anaerobic particular, ethanol consumption leads altered liver metabolism, which when excessive associated with adverse medical conditions including fatty disease, hepatitis, cirrhosis, and cancer. Here we present...
Abstract Hepatocellular carcinoma (HCC), the primary form of human adult liver malignancy, is a highly aggressive tumor with average survival rates that are currently less than 1 year following diagnosis. Most patients HCC diagnosed at an advanced stage, and no efficient marker exists for prediction prognosis and/or response(s) to therapy. We have reported previously high level [1‐ 13 C]alanine in orthotopic using single‐voxel hyperpolarized C]pyruvate MRS. In present study, we implemented...
Dynamic hyperpolarized [1- 13 C]pyruvate metabolic imaging in the normal anesthetized rat brain is demonstrated on a clinical 3-T magnetic resonance scanner. A 12-second bolus injection of imaged at 3-second temporal resolution. The observed dynamics are evaluated with regard to cerebral blood volume (CBV), flow, transport, and exchange lactate pool. model for C]lactate, based blood–brain transport kinetics, CBV, pyruvate described.