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Wind RA, Hu JZ, Majors PD. Slow-MAS NMR: A new technology for in vivo metabolomic studies. DRUG DISCOVERY TODAY. TECHNOLOGIES 2014; 2:291-4. [PMID: 24981950 DOI: 10.1016/j.ddtec.2005.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obtaining detailed in vivo metabolic information has been identified as key elements of better understanding the efficacy and toxicity of new therapies. A new nuclear magnetic resonance (NMR) technology called LOCMAT is reported in this paper that yields substantially increased spectral resolution in spatially localized in vivo H NMR metabolite spectra, as illustrated by measurements in the liver of a live mouse. LOCMAT promises to significantly enhance the utility of NMR spectroscopy for biomedical research.:
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Affiliation(s)
- Robert A Wind
- Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, 3335 Q Avenue, Richland, WA 99352, USA.
| | - Jian Z Hu
- Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, 3335 Q Avenue, Richland, WA 99352, USA
| | - Paul D Majors
- Pacific Northwest National Laboratory, P.O. Box 999, MS K8-98, 3335 Q Avenue, Richland, WA 99352, USA
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Tsai SY, Otazo R, Posse S, Lin YR, Chung HW, Wald LL, Wiggins GC, Lin FH. Accelerated proton echo planar spectroscopic imaging (PEPSI) using GRAPPA with a 32-channel phased-array coil. Magn Reson Med 2008; 59:989-98. [PMID: 18429025 DOI: 10.1002/mrm.21545] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Shang-Yueh Tsai
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
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Ulrich M, Wokrina T, Ende G, Lang M, Bachert P. 31P-{1H} echo-planar spectroscopic imaging of the human brain in vivo. Magn Reson Med 2007; 57:784-90. [PMID: 17390361 DOI: 10.1002/mrm.21192] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Echo-planar spectroscopic imaging (EPSI) is one of the fastest spectroscopic imaging (SI) methods. It has been applied to (1)H MR spectroscopy (MRS) studies of the human brain in vivo. However, to our knowledge, EPSI with detection of the (31)P nucleus to monitor phosphorus-containing neurometabolites has not yet been considered. In this work, eight different (31)P-{(1)H} EPSI sequence versions with spectral widths ranging from 313 Hz to 2.27 kHz were implemented on a clinical 1.5T whole-body MR tomograph. The sequence versions utilized the heteronuclear nuclear Overhauser effect (NOE) for (31)P signal enhancement. The sensitivity observed in experiments with model solutions was in good agreement with theoretical predictions. In vivo measurements performed on healthy volunteers (N = 16) demonstrated the feasibility of performing two-dimensional (2D) (31)P-{(1)H} EPSI in the human brain, and the technique enabled fast acquisition of well-resolved localized spectra.
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Affiliation(s)
- M Ulrich
- Department of Neuroimaging, Central Institute of Mental Health, Mannheim, Germany.
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Richards TL, Aylward EH, Field KM, Grimme AC, Raskind W, Richards AL, Nagy W, Eckert M, Leonard C, Abbott RD, Berninger VW. Converging evidence for triple word form theory in children with dyslexia. Dev Neuropsychol 2006; 30:547-89. [PMID: 16925475 DOI: 10.1207/s15326942dn3001_3] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
This article has 3 parts. The 1st part provides an overview of the family genetics, brain imaging, and treatment research in the University of Washington Multidisciplinary Learning Disabilities Center (UWLDC) over the past decade that points to a probable genetic basis for the unusual difficulty that individuals with dyslexia encounter in learning to read and spell. Phenotyping studies have found evidence that phonological, orthographic, and morphological word forms and their parts may contribute uniquely to this difficulty. At the same time, reviews of treatment studies in the UWLDC (which focused on children in Grades 4 to 6) and other research centers provide evidence for the plasticity of the brain in individuals with dyslexia. The 2nd part reports 4 sets of results that extend previously published findings based on group analyses to those based on analyses of individual brains and that support triple word form awareness and mapping theory: (a) distinct brain signatures for the phonological, morphological, and orthographic word forms; (b) crossover effects between phonological and morphological treatments and functional magentic resonance imaging (fMRI) tasks in response to instruction, suggestive of cross-word form computational and mapping processes; (c) crossover effects between behavioral measures of phonology or morphology and changes in fMRI activation following treatment; and (d) change in the relationship between structural MRI and functional magnetic resonance spectroscopy (fMRS) lactate activation in right and left inferior frontal gyri following treatment emphasizing the phonological, morphological, and orthographic word forms. In the 3rd part we discuss the next steps in this programmatic research to move beyond word form alone.
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Affiliation(s)
- Todd L Richards
- Department of Radiology, University of Washington, Seattle, WA 98195, USA.
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Mulkern RV, Chen NK, Oshio K, Panych LP, Rybicki FJ, Gambarota G. Fast spectroscopic imaging strategies for potential applications in fMRI. Magn Reson Imaging 2005; 22:1395-405. [PMID: 15707789 DOI: 10.1016/j.mri.2004.10.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Accepted: 10/08/2004] [Indexed: 01/28/2023]
Abstract
Technical aspects of two general fast spectroscopic imaging (SI) strategies, one based on gradient echo trains and the other on spin echo trains, are reviewed within the context of potential applications in the field of functional magnetic resonance imaging (fMRI). Fast spectroscopic imaging of water may prove useful for identifying mechanisms underlying the blood oxygenation level dependence (BOLD) of the water signal during brain activation studies. Reasonably rapid mapping of changes in proton signals from brain metabolites, like lactate, creatine or even neurotransmitter associated metabolites like GABA, is substantially more challenging but technically feasible particularly as higher field strengths become available. Fast spectroscopic methods directed towards the 31P signals from phosphocreatine (PCr) and adenosine tri-phosphates (ATP) are also technically feasible and may prove useful for studying cerebral energetics within fMRI contexts.
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Affiliation(s)
- Robert V Mulkern
- Department of Radiology, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Abstract
The neurophysiological basis of cognition is relatively unexplained, with most studies reporting weak relationships between cognition and measures of brain function, such as event-related potentials, brain size and cerebral blood flow. Magnetic resonance spectroscopy (MRS) is an in vivo method used to detect neurochemicals within the brain that are relevant to certain brain processes. The most widely used methods are 1H-MRS and 31P-MRS, which detect compounds that contain hydrogen and phosphorus, respectively. Recent studies have shown that the absolute concentrations or ratios of these neurochemicals, in particular N-acetyl aspartate (NAA), which is associated with neuronal viability, correlate with performance on neuropsychological tests or other measures of cognitive function in normal subjects. Many studies in adults and children have shown a relationship between neurometabolite values and cognitive status or extent of cognitive dysfunction in various neurological and neuropsychiatric disorders. We review these studies and conclude that MRS has potential applications for the study of cognitive processes in health and disease and may be used clinically for differential diagnosis, the early detection of pathology and the examination of longitudinal change.
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Affiliation(s)
- Amy J Ross
- School of Psychiatry, University of New South Wales, Kensington, New South Wales 2033, Australia.
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Abstract
PURPOSE To determine if children with speech delay who have been sedated have patterns of activation to passive language paradigms that are different than those of children with normal speech. MATERIALS AND METHODS Seventeen children with speech delay (age range, 2-7 years; mean, 4.0 years) and 35 age-matched children with normal speech (age range, 2-8 years; mean, 4.2 years) were evaluated. The subjects in the control group were selected from patients referred for conventional magnetic resonance (MR) imaging. All children had absence of auditory impairment or mental retardation, and MR findings indicated that brain structure was normal. Sedation was achieved with pentobarbital (3-5 mg/kg) or chloral hydrate (75 mg/kg). Functional MR imaging was performed with a single-shot echo-planar blood oxygen-level-dependent technique and a passive block paradigm, in which the child listened to his or her mother's prerecorded voice. Statistical postprocessing of functional MR images was performed with the t test and cluster detection methods. Comparison between groups was performed depending on the type of data with a nonparametrical Mann-Whitney test, parametrical t test, or Fisher exact test. RESULTS Five (83%) of the six children older than 3 years with speech delay had lateralized activation of functional MR imaging signal in the right hemisphere. Ten (71%) of 14 age-matched patients with normal speech had activation in the left hemisphere when exposed to the same passive listening tasks. When these groups were compared, this difference was statistically significant. (P =.036). No statistically significant lateralization was seen across all age groups in children with activation. CONCLUSION Children older than 3 years with speech delay have activation in the right hemisphere more frequently than children older than 3 years with normal speech, who often have the expected finding of activation in the left hemisphere.
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Affiliation(s)
- Byron Bernal
- Department of Radiology, Miami Childrens' Hospital, 3100 SW 62nd Ave, Miami, FL 33155, USA
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Sachs BC, Gaillard WD. Organization of language networks in children: functional magnetic resonance imaging studies. Curr Neurol Neurosci Rep 2003; 3:157-62. [PMID: 12583845 DOI: 10.1007/s11910-003-0068-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Functional magnetic resonance imaging (fMRI) is a relatively new neuroimaging procedure that has been used to study a wide variety of cognitive phenomena in adults, including attention, language, and memory. More recently, this technique has been successfully applied to pediatric populations as well. In particular, many investigators have employed fMRI as a tool to study language development in normal children. This paper reviews the current imaging research on the identification of cortex subserving components of language processing in young children. The literature suggests that fMRI can successfully identify regions of language cortex in children in much the same capacity as it can with adults, and that generally, adults and children show fundamental similarities in the patterns of activation. However, special considerations with pediatric imaging, paradigm design, and image analysis are also discussed.
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Affiliation(s)
- Bonnie C Sachs
- Department of Neurology, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
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Balsamo LM, Gaillard WD. The utility of functional magnetic resonance imaging in epilepsy and language. Curr Neurol Neurosci Rep 2002; 2:142-9. [PMID: 11898481 DOI: 10.1007/s11910-002-0023-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Functional magnetic resonance imaging (fMRI) is a viable presurgical tool for use with the pediatric epilepsy population as replacement for the intra-carotid sodium amobarbital test (IAT) used to identify hemispheric language dominance. This paper reviews the current imaging research on the identification of language cortex in pediatric epilepsy patients and in normal children. A review of the literature comparing fMRI to the IAT and electrocortical stimulation suggests that fMRI reliably identifies the dominant hemisphere, with pediatric and adult studies producing comparable results. Within-hemisphere localization of eloquent cortex with fMRI is more problematic. Paradigm selection, data analysis techniques, and considerations specific to imaging children are discussed. Utility of fMRI for studying neural plasticity as a result of brain insult (e.g., epilepsy) is also considered.
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Affiliation(s)
- Lyn M Balsamo
- Department of Neurology, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
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Abstract
Magnetic resonance spectroscopy (MRS) provides a useful method for studying a number of psychotropic medications and metabolites in human brain in vivo. New insights regarding the pharmacokinetic and pharmacodynamic properties of psychotropic medications in the target organ (i.e., brain) have been obtained using lithium-7 MRS and fluorine-19 MRS. Both proton and phosphorus-31 MRS have significantly enhanced our knowledge of the pathophysiology of a number of psychiatric disorders by providing estimates of brain concentrations of several important cerebral metabolites. Efforts are also being made to link MRS measures of cerebral metabolism with neurophysiologic and neurocognitive processes. Ongoing improvement and refinement in MRS techniques, including the installation of scanners with increased magnetic field strength and better methods of data processing, will improve both spatial and temporal resolution. In addition, efforts to develop multisite research studies may result in greater standardization of MRS procedures and methods for interpretation of results. In this review, the current status of MRS applications in psychiatric research is reviewed, and new frontiers and possible future developments are discussed.
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Affiliation(s)
- In Kyoon Lyoo
- McLean Hospital Brain Imaging Center, Belmont, Massachusetts 02478, USA
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Corina DP, Richards TL, Serafini S, Richards AL, Steury K, Abbott RD, Echelard DR, Maravilla KR, Berninger VW. fMRI auditory language differences between dyslexic and able reading children. Neuroreport 2001; 12:1195-201. [PMID: 11338191 DOI: 10.1097/00001756-200105080-00029] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
During fMRI, dyslexic and control boys completed auditory language tasks (judging whether pairs of real and/or pseudo words rhymed or were real words) in 30 s 'on' conditions alternating with a 30 s 'off' condition (judging whether tone pairs were same). During phonological judgment, dyslexics had more activity than controls in right than left inferior temporal gyrus and in left precentral gyrus. During lexical judgment, dyslexics were less active than controls in bilateral middle frontal gyrus and more active than controls in left orbital frontal cortex. Individual dyslexics were reliably less active than controls in left insula and left inferior temporal gyrus. Dyslexic and control children differ in brain activation during auditory language processing skills that do not require reading.
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Affiliation(s)
- D P Corina
- Department of Radiology, University of Washington, Box 357115, University of Washington, Seattle, WA 98195-7115, USA
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Beckmann N, Gentsch C, Baumann D, Bruttel K, Vassout A, Schoeffter P, Loetscher E, Bobadilla M, Perentes E, Rudin M. Current awareness. NMR IN BIOMEDICINE 2001; 14:217-222. [PMID: 11357188 DOI: 10.1002/nbm.669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 9 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Brain and Nerves; 5 Neuropathology; 6 Cancer; 7 Cardiac, Vascular and Respiratory Systems; 8 Liver, Kidney and Other Organs; 9 Muscle and Orthopaedic. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted.
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Affiliation(s)
- N Beckmann
- Core Technologies Area, Novartis Pharma AG, CH-4002 Basel, Switzerland
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