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Sample records for 1h magnetic resonance

  1. 1H magnetic resonance spectroscopy of the prostate

    To provide a brief summary of important technical and biochemical aspects and current clinical applications of magnetic resonance spectroscopy (MRS) of the prostate.Material and methods Pertinent radiological and biochemical literature was searched and retrieved via electronic media (medline trademark, pubmed trademark). Basic concepts of MRS of the prostate and its clinical applications were extracted to provide an overview. The prostate lends itself to MRS due to its unique production, storage, and secretion of citrate. While healthy prostate tissue demonstrates high levels of citrate and low levels of choline that marks cell wall turnover, prostate cancer (PCA) utilizes citrate for energy metabolism and shows high levels of choline. The ratio of (choline + creatine)/citrate differentiates healthy prostate tissue and PCA. The combination of magnetic resonance imaging (MRI) and 3-dimensional MRS (3D-MRSI or 3D-CSI) of the prostate localizes PCA to a sextant of the peripheral zone of the prostate with sensitivity/specificity of up to 80/80%. Combined MRI and 3D-MRSI exceed the sensitivity and specificity of sextant biopsy of the prostate. When MRS and MRI agree on PCA presence, the positive predictive value is about 90%. In principle, combined MRI and 3D-MRSI recognize and localize remnant or recurrent cancer after hormone therapy, radiation therapy and cryo-surgery. Since it is non-invasive and radiation-free, combined MRI and 3D-MRSI lends itself to the planning of prostate biopsy and therapy as well as to post-therapeutic follow-up. For broad clinical application, it will be necessary to facilitate MRS examinations and their evaluation and make MRS available to a wider range of institutions. (orig.)

  2. 1H and 31P nuclear magnetic resonance spectroscopy of erythrocyte extracts in myotonic muscular dystrophy

    Extracts freshly prepared from erythrocytes of patients with myotonic muscular dystrophy, their unaffected siblings, and normal control subjects were examined with both 1H and 31P nuclear magnetic resonance spectroscopy. A moderate variability was found in the relative amounts of various nonphosphorylated compounds among patients and control subjects; however, no significant differences were found between the groups. As for the phosphorylated compounds, the sum of ADP+ATP was found significantly elevated in the myotonic muscular dystrophy patients

  3. Application of 1H magnetic resonance spectroscopy in diagnosis and differential diagnosis of cerebral infection

    Objective: To study the application of single voxel proton magnetic resonance spectroscopy in diagnosis and differential diagnosis of cerebral infection according to manifestations of the 8 patients with cerebritis and 13 patients with gliomas. Methods: The patients including 8 cerebral abscess and 13 gliomas were examined with MRS. And the quantity of the NAA, Cho, Cr, Lip, Lac, AA were measured and compared. Results: There were differences between cerebral abscess and tumors on MRS. NAA/Cr and Cho/Cr of abscess were 4.114±3.637 and 3.084±0.933. NAA/Cr and Cho/Cr of tumors were 1.064±0.823 and 5.987±4.380. There was amino acids (AA) could be seen in some of cerebral abscess. Conclusion: 1H magnetic resonance spectroscopy can supply important information in diagnosis cerebral infection and differentiate information with tumor. (authors)

  4. A sup 1 H nuclear magnetic resonance study of structural and organisational changes in the cell

    Tunnah, S K

    2000-01-01

    Increasing importance is being placed on understanding the role of membrane lipids in many different areas of biochemistry. It is of interest to determine what interactions may occur between membrane lipids and drug species. Furthermore, an increasing body of evidence suggests that membrane lipids are involved in the pathology of numerous diseases such as rheumatoid arthritis, cancer and HIV. Clearly, the more information available on the mechanisms involved in diseases, the greater the potential for identifying a cure or even a prevention. sup 1 H nuclear magnetic resonance (NMR) spectroscopy was used to study the alterations in membrane lipid organisation and structure in intact, viable cultured cells. Changes in the sup 1 H NMR spectra and the spin-lattice relaxation measurements of the human K562 and the rat FRTL-5 cell lines were observed on the addition of the fatty acid species: triolein, evening primrose oil, arachidonic acid and ITF 1779. Results indicate that the membrane lipids are reorganised to a...

  5. Serum metabolic signature of minimal hepatic encephalopathy by (1)H-nuclear magnetic resonance.

    Jiménez, Beatriz; Montoliu, Carmina; MacIntyre, David A; Serra, Miguel A; Wassel, Abdallah; Jover, María; Romero-Gomez, Manuel; Rodrigo, Jose M; Pineda-Lucena, Antonio; Felipo, Vicente

    2010-10-01

    Minimal hepatic encephalopathy (MHE) reduces quality of life of cirrhotic patients, predicts overt hepatic encephalopathy, and is associated with poor prognosis. We hypothesized that MHE arises once metabolic alterations derived from the liver reach a particular threshold. Our aim was to assess whether metabolic profiling of serum samples by high-field (1)H-nuclear magnetic resonance spectroscopy ((1)H NMR) and subsequent multivariate analyses would be useful to characterize metabolic perturbations associated with MHE and to identify potential metabolic biomarkers. Metabolic serum profiles from controls (n = 69) and cirrhotic patients without MHE (n = 62) and with MHE (n = 39) were acquired using high field NMR. Supervised modeling of the data provided perfect discrimination between healthy controls and cirrhotic patients and allowed the generation of a predictive model displaying strong discrimination between patients with and without MHE (R(2)Y = 0.68, Q(2)Y = 0.63). MHE patients displayed increased serum concentrations of glucose, lactate, methionine, TMAO, and glycerol, as well as decreased levels of choline, branch amino acids, alanine, glycine, acetoacetate, NAC, and lipid moieties. Serum metabonomics by (1)H NMR offers a useful approach for characterizing underlying metabolic differences between patients with and without MHE. This procedure shows great potential as a diagnostic tool of MHE as it objectively reflects measurable biochemical differences between the patient groups and may facilitate monitoring of both disease progression and effects of therapeutic treatments. PMID:20690770

  6. Single voxel 1 H magnetic resonance spectroscopy in the diagnosis of musculoskeletal mass lesions

    Shalini Agarwal

    2014-01-01

    Full Text Available Introduction: In vivo magnetic resonance spectroscopy (MRS is an established technique for evaluation of malignant tumors in brain, breast, prostate, etc., However, its efficacy in the diagnosis of musculoskeletal (MSK mass lesions is yet to be established. We present our experience with MRS of these lesions. Materials and Methods: Magnetic resonance imaging (MRI, dynamic contrast-enhanced MRI and single-voxel 1 H MRS was performed in 30 consecutive patients with histologically proven benign and malignant MSK tumors/mass lesions each, on a 1.5-T magnetic resonance scanner. MRS was performed with echo times (TE of 40, 135 and 270 ms. A clearly identifiable peak at 3.2 ppm in at least two of the three spectra acquired at the three TE was taken as positive for choline. MRS imaging and enhancement patterns were compared in these two groups and were analyzed by a Radiologist blinded to the histopathological findings. Results: Ages of patients in the malignant age group ranged from 2 to 65 years (M: F - 19:11 while that of patients in the benign group ranged from 7 months to 56 years (M: F - 17:13. There were two patients with Type I curve, 18 with Type II curve and 10 with Type III curve on dynamic contrast enhanced images in the malignant group while there were no patients with Type I curve, 5 with Type II curve and 25 with Type III curve in the benign group. The sensitivity of MRS for predicting malignancy was 60%, specificity was 93.33%, positive predictive value was 90%, negative predictive value was 70% and accuracy was 76.66%. Conclusion: MRS is a promising technique for evaluation of MSK mass lesions. The accuracy at present remains low. We recommend that it be used as an adjunct to routine MRI.

  7. Quantification of choline concentration following liver cell apoptosis using 1H magnetic resonance spectroscopy

    Zhi-Wei Shen; Zhen Cao; Ke-Zeng You; Zhong-Xian Yang; Ye-Yu Xiao; Xiao-Fang Cheng; Yao-Wen Chen

    2012-01-01

    AIM:To evaluate the feasibility of quantifying liver choline concentrations in both normal and apoptotic rabbit livers in vivo,using 1H magnetic resonance spectroscopy (1H-MRS).METHODS:1H-MRS was performed in 18 rabbits using a 1.5T GE MR system with an eight-channel head/neck receiving coil.Fifteen rabbits were injected with sodium selenite at a dose of 10 μmol/kg to induce the liver cell apoptosis.Point-resolved spectroscopy sequencelocalized spectra were obtained from 10 livers once before and once 24 h after sodium selenite injection in vivo.T1 and T2 relaxation time of water and choline was measured separately in the livers of three healthy rabbits and three selenite-treated rabbits.Hematoxylin and eosin and dUTP-biotin nick end labeling (TUNEL) staining was used to detect and confirm apoptosis.Choline peak areas were measured relative to unsuppressed water using LCModel.Relaxation attenuation was corrected using the average of T1 and T2 relaxation time.The choline concentration was quantified using a formula,which was tested by a phantom with a known concentration.RESULTS:Apoptosis of hepatic cells was confirmed by TUNEL assay.In phantom experiment,the choline concentration (3.01 mmol/L),measured by 1H-MRS,was in good agreement with the actual concentration (3 mmol/L).The average T1 and T2 relaxation time of choline was 612 ± 15 ms and 74 ± 4 ms in the control group and 670 ± 27 ms and 78 ± 5 ms in apoptotic livers in vivo,respectively.Choline was quantified in 10 rabbits,once before and once after the injection with sodium selenite.The choline concentration decreased from 14.5 ± 7.57 mmol/L before sodium selenite injection to 10.8 ± 6.58 mmol/L (mean ± SD,n =10) after treatment (Z =-2.395,P < 0.05,two-sample paired Wilcoxon test).CONCLUSION:1H-MRS can be used to quantify liver choline in vivo using unsuppressed water as an internal reference.Decreased liver choline concentrations are found in sodium selenite-treated rabbits undergoing liver cell

  8. {sup 1}H and {sup 31}P-magnetic resonance spectroscopy of cerebral infarction in rats

    Yamamuro, Manabu; Katayama, Yasuo; Igarashi, Hironaka; Terashi, Akiro [Nippon Medical School, Tokyo (Japan)

    1997-04-01

    Magnetic resonance spectroscopy (MRS) allows the noninvasive study of metabolism in vivo. In order to further understand the time course of biochemical changes during cerebral infarction, we performed the MRS study with pathological analysis. The left middle cerebral artery (MCA) was occluded in spontaneously hypertensive male rats (SHR) by the method of Tamura et al. The spectra were obtained from the infarcted hemisphere by placing the surface coils over the left side of the calvarium. {sup 31}P and {sup 1}H-MRS were performed at 3 hours, 24 hours and 7 days after MCA occlusion. Ischemic lesions caused by the left MCA occlusion extended into the parietal lobe and caudate putamen. After 3 hours of ischemia, vacuolated neurophils and shrunken neurons were observed. At 24 hours, these changes were severe. After 7 days, infiltration of monocytes and capillary hyperplasia were seen, and neurons had disappeared. At the acute stage of ischemia the phosphocreatine/inorganic phosphate (PCr/Pi) peak ratio decreased. After 7 days of ischemia, these changes became obscure. The intracellular pH (pHi) decreased after 3 hours of ischemia and recovered almost to the control level at 24 hours post ischemia. Alkalosis was apparent 7 days after ischemia. This alkalosis might be due to increased permeability of the deteriorated blood brain barrier. Although the lactate level was high 24 hours post ischemia, the pHi was almost normal. The N-acetyl-aspartate/creatine ratio decreased significantly from the acute stage of stroke. This decrease correlated with pathological changes. The correlation of the magnetic resonance spectra with the histological results may open aspects for monitoring stroke therapy and a new approach to tissue characterization. (author)

  9. 1H magnetic resonance spectroscopy in the diagnosis of paediatric low grade brain tumours

    Introduction: Low grade gliomas are the commonest brain tumours in children but present in a myriad of ways, each with its own treatment challenges. Conventional MRI scans play an important role in their management but have limited ability to identify likely clinical behaviour. The aim of this study is to investigate 1H magnetic resonance spectroscopy (MRS) as a method for detecting differences between the various low grade gliomas and related tumours in children. Patients and methods: Short echo time single voxel 1H MRS at 1.5 or 3.0 T was performed prior to treatment on children with low grade brain tumours at two centres and five MR scanners, 69 cases had data which passed quality control. MRS data was processed using LCModel to give mean spectra and metabolite concentrations which were compared using T-tests, ANOVA, Receiver Operator Characteristic curves and logistic regression in SPSS. Results: Significant differences were found in concentrations of key metabolites between glioneuronal and glial tumours (T-test p < 0.05) and between most of the individual histological subtypes of low grade gliomas. The discriminatory metabolites identified, such as choline and myoinositol, are known tumour biomarkers. In the set of pilocytic astrocytomas and unbiopsied optic pathway gliomas, significant differences (p < 0.05, ANOVA) were found in metabolite profiles of tumours depending on location and patient neurofibromatosis type 1 status. Logistic regression analyses yielded equations which could be used to assess the probability of a tumour being of a specific type. Conclusions: MRS can detect subtle differences between low grade brain tumours in children and should form part of the clinical assessment of these tumours

  10. A 1H nuclear magnetic resonance study of structural and organisational changes in the cell

    Increasing importance is being placed on understanding the role of membrane lipids in many different areas of biochemistry. It is of interest to determine what interactions may occur between membrane lipids and drug species. Furthermore, an increasing body of evidence suggests that membrane lipids are involved in the pathology of numerous diseases such as rheumatoid arthritis, cancer and HIV. Clearly, the more information available on the mechanisms involved in diseases, the greater the potential for identifying a cure or even a prevention. 1H nuclear magnetic resonance (NMR) spectroscopy was used to study the alterations in membrane lipid organisation and structure in intact, viable cultured cells. Changes in the 1H NMR spectra and the spin-lattice relaxation measurements of the human K562 and the rat FRTL-5 cell lines were observed on the addition of the fatty acid species: triolein, evening primrose oil, arachidonic acid and ITF 1779. Results indicate that the membrane lipids are reorganised to accommodate the interpolation of these molecules. The spatial arrangement adopted by each of these species appeared to dictate its effect on the lipids. Doxorubicin and menadione, both known to cause oxidative stress, were added to K562 cells. Although both agents are known to act by different mechanisms, the NMR data and scanning electron microscopy suggested that both caused similar alterations in the membrane organisation and lipid fluidity. Protrusions were formed indicating areas of weakness in the membrane. Spin-echo NMR was employed to investigate the action of the thiol-containing compounds, penicillamine, captopril and N-acetylcysteine in erythrocytes under conditions of oxidative stress. Results indicate that while captopril acts as a free radical scavenger, penicillamine may act as either oxidant or reductant. N-acetylcysteine was observed to act as a reducing agent. (author)

  11. {sup 1}H magnetic resonance spectroscopy in the diagnosis of paediatric low grade brain tumours

    Orphanidou-Vlachou, E., E-mail: eleni.orphanidou@googlemail.com [School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Birmingham Children' s Hospital NHS Foundation Trust, Whittall Street, Birmingham, B4 6NH (United Kingdom); Auer, D., E-mail: dorothee.auer@nottingham.ac.uk [Division of Academic Radiology, School of Medical and Surgical Sciences, The University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Children' s Brain Tumour Research Centre, Queens Medical Centre, University of Nottingham (United Kingdom); Brundler, M.A., E-mail: marie-anne.brundler@bch.nhs.uk [Birmingham Children' s Hospital NHS Foundation Trust, Whittall Street, Birmingham, B4 6NH (United Kingdom); Davies, N.P., E-mail: nigel.davies@nhs.net [School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT (United Kingdom); Birmingham Children' s Hospital NHS Foundation Trust, Whittall Street, Birmingham, B4 6NH (United Kingdom); Department of Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Mindelsohn Way, Edgbaston, Birmingham, B15 2WB (United Kingdom); Jaspan, T., E-mail: tim.jaspan@nuh.nhs.uk [Children' s Brain Tumour Research Centre, Queens Medical Centre, University of Nottingham (United Kingdom); MacPherson, L., E-mail: Lesley.MacPherson@bch.nhs.uk [Birmingham Children' s Hospital NHS Foundation Trust, Whittall Street, Birmingham, B4 6NH (United Kingdom); Natarajan, K., E-mail: Kal.Natarajan@uhb.nhs.uk [Birmingham Children' s Hospital NHS Foundation Trust, Whittall Street, Birmingham, B4 6NH (United Kingdom); Department of Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Mindelsohn Way, Edgbaston, Birmingham, B15 2WB (United Kingdom); and others

    2013-06-15

    Introduction: Low grade gliomas are the commonest brain tumours in children but present in a myriad of ways, each with its own treatment challenges. Conventional MRI scans play an important role in their management but have limited ability to identify likely clinical behaviour. The aim of this study is to investigate {sup 1}H magnetic resonance spectroscopy (MRS) as a method for detecting differences between the various low grade gliomas and related tumours in children. Patients and methods: Short echo time single voxel {sup 1}H MRS at 1.5 or 3.0 T was performed prior to treatment on children with low grade brain tumours at two centres and five MR scanners, 69 cases had data which passed quality control. MRS data was processed using LCModel to give mean spectra and metabolite concentrations which were compared using T-tests, ANOVA, Receiver Operator Characteristic curves and logistic regression in SPSS. Results: Significant differences were found in concentrations of key metabolites between glioneuronal and glial tumours (T-test p < 0.05) and between most of the individual histological subtypes of low grade gliomas. The discriminatory metabolites identified, such as choline and myoinositol, are known tumour biomarkers. In the set of pilocytic astrocytomas and unbiopsied optic pathway gliomas, significant differences (p < 0.05, ANOVA) were found in metabolite profiles of tumours depending on location and patient neurofibromatosis type 1 status. Logistic regression analyses yielded equations which could be used to assess the probability of a tumour being of a specific type. Conclusions: MRS can detect subtle differences between low grade brain tumours in children and should form part of the clinical assessment of these tumours.

  12. Purity Assessment of Aryltetralin Lactone Lignans by Quantitative 1H Nuclear Magnetic Resonance

    Yan-Jun Sun

    2015-05-01

    Full Text Available In the present work, a quantitative 1H Nuclear Magnetic Resonance (qHNMR was established for purity assessment of six aryltetralin lactone lignans. The validation of the method was carried out, including specificity, selectivity, linearity, accuracy, precision, and robustness. Several experimental parameters were optimized, including relaxation delay (D1, scan numbers (NS, and pulse angle. 1,4-Dinitrobenzene was used as internal standard (IS, and deuterated dimethyl sulfoxide (DMSO-d6 as the NMR solvent. The purities were calculated by the area ratios of H-2,6 from target analytes vs. aromatic protons from IS. Six aryltetralin lactone lignans (deoxypodophyllotoxin, podophyllotoxin, 4-demethylpodophyllotoxin, podophyllotoxin-7′-O-β-d-glucopyranoside, 4-demethylpodophyllotoxin-7′-O-β-d-glucopyranoside, and 6′′-acetyl-podophyllotoxin-7′-O-β -d-glucopyranoside were analyzed. The analytic results of qHNMR were further validated by high performance liquid chromatography (HPLC. Therefore, the qHNMR method was a rapid, accurate, reliable tool for monitoring the purity of aryltetralin lactone lignans.

  13. Interleaved localized 1H/31P nuclear magnetic resonance spectroscopy of skeletal muscle

    Nuclear magnetic resonance (NMR) has been used as a spectroscopic method in physics and chemistry before it was developed to become a diagnostic imaging tool in medicine. When NMR spectroscopy is applied to human tissue, metabolism can be studied in normal physiological and pathological states in vivo. Metabolite concentrations and rates can be monitored dynamically and with localization of a defined region of interest. The 'window' which is opened for observation, i.e. which quantities are measured, depends on the nucleus used for RF excitation. Mechanisms of adenosine tri-phosphate (ATP) resynthesis, as a direct source of energy for muscle contraction, are phosphocreatine (PCr) splitting, glycolysis, beta-oxidation and, finally, oxidative phosphorylation. Whilst the dependency of these processes' fractional contribution to muscular energy supply on exercise type and duration is well known, quantitative models of the regulating mechanisms involved are still subject of current research. A large fraction of the established knowledge about metabolism is based on biochemical analysis of tissue acquired invasively (e.g. microdialysis and open-flow microperfusion) or representing averaged metabolic concentrations for the whole body (via serum metabolites or gas exchange analysis). Localized NMR spectroscopy, however, is capable of non-invasively acquiring time-resolved data from a defined volume of interest, in vivo. In contrast to the vast majority of MRS studies investigating metabolism, where spectra of a single nucleus (commonly 1H, 31P or 13C) were acquired or several MR spectra with different nuclei were measured in separate experiments, this work opens an additional 'window' on muscle metabolism by interleaved localized acquisition of 1H and 31P NMR spectra from human calf muscle in vivo, during rest, exercise and recovery, in a single experiment. Using this technique, the time courses of the concentrations of phosphocreatine, inorganic phosphate (Pi), ATP, total

  14. 1H magnetic resonance spectroscopy (1H MRS) in the initially differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis

    Objective: To evaluate 1H magnetic resonance spectroscopy (1H MRS) in the differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis. Methods: Fifteen patients who had clinical and CT, MRI changes that suggested a diagnosis of delayed cerebral necrosis or recurrent brain tumor after radiation therapy and 5 patients who had a definite clinical diagnosis of delayed cerebral necrosis underwent single MR spectroscopy simultaneously both in the lesion's region and the contralateral side. Results: Of the former 15 cases who proved by surgical pathology, 14 cases were gliomas, 1 case was delayed cerebral necrosis, and their etiologic diagnoses of 1H MRS were correct. (1) 1H MRS in 14 cases with gliomas exhibited specific spectral peaks including prominent choline-containing compounds (Cho), decreased or absent acetylaspartate (NAA) and total creatine (Cr), and the metabolic ratios showed significantly increased Cho/Cr, decreased NAA/Cr. Twelve cases showed abnormal lactate (Lac). (2) Among 6 cases with delayed cerebral necrosis, 5 cases exhibited decreased or absent Cho, NAA, Cr, and abnormal Lipid, 1 case showed absent Cho, NAA, and Cr with a flat curve without Lac. Conclusion: 1H MRS was positively claimed for differentiating recurrent brain gliomas after radiation therapy from delayed cerebral necrosis

  15. 1H magnetic resonance spectroscopy of the brain in paediatrics: The diagnosis of creatine deficiencies

    Sijens, P.E.; Oudkerk, M.

    2005-01-01

    The diagnosis of creatine deficiencies, a paediatric application of magnetic resonance spectroscopy that has already become a diagnostic tool in clinical practice, is reviewed and illustrated with results from recent examinations

  16. Non-invasive assessment of hepatic fat accumulation in chronic hepatitis C by 1H magnetic resonance spectroscopy

    Background: Liver biopsy is the standard method for diagnosis of hepatic steatosis, but is invasive and carries some risk of morbidity. Aims and methods: Quantification of hepatocellular lipid content (HCL) with non-invasive single voxel 1H magnetic resonance spectroscopy (MRS) at 3 T was compared with histological grading and biochemical analysis of liver biopsies in 29 patients with chronic hepatitis C. Body mass index, indices of insulin resistance (homeostasis model assessment index, HOMA-IR), serum lipids and serum liver transaminases were also quantified. Results: HCL as assessed by 1H MRS linearly correlated (r = 0.70, p 1H MRS (r = 0.63, p 1H MRS is a valid and useful method for quantification of HCL content in patients with chronic hepatitis C and can be easily applied to non-invasively monitoring of steatosis during repeated follow-up measurements in a clinical setting.

  17. A sample preparation protocol for 1H nuclear magnetic resonance studies of water-soluble metabolites in blood and urine.

    Sheedy, John R; Ebeling, Peter R; Gooley, Paul R; McConville, Malcolm J

    2010-03-15

    We describe a general protocol for preparing protein-containing biofluids for (1)H nuclear magnetic resonance (NMR) metabolomic studies. In this protocol, untreated samples are diluted in deuterated solvents to precipitate proteins and recover metabolites quantitated relative to standard reference compounds such as 3-trimethylsilylpropionic acid (TSP) and 2,2-dimethyl-2-silapentane-5-sulfonic acid (DSS). The efficacy of this protocol was tested using a bovine serum albumin/metabolite mix and human serum samples. This sample preparation method can be readily applied to any protein-containing biofluid for (1)H NMR studies. PMID:19941831

  18. Longitudinal monitoring of metabolic alterations in cuprizone mouse model of multiple sclerosis using 1H-magnetic resonance spectroscopy.

    Orije, Jasmien; Kara, Firat; Guglielmetti, Caroline; Praet, Jelle; Linden, van der, M.; Ponsaerts, Peter; Verhoye, Marleen

    2015-01-01

    Non-invasive measures of well-known pathological hallmarks of multiple sclerosis (MS) such as demyelination, inflammation and axonal injury would serve as useful markers to monitor disease progression and evaluate potential therapies. To this end, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) provides a powerful means to monitor metabolic changes in the brain and may be sensitive to these pathological hallmarks. In our study, we used the cuprizone mouse model to study pa...

  19. Early Biomarkers in 1H Nuclear Magnetic Resonance Spectroscopy of Striatal Pathological Mechanisms after Acute Carbon Monoxide Poisoning in Rats

    GUAN Li; LI Zong Yang; ZHANG Yan Lin; CONG Cui Cui; ZHAO Jin Yuan

    2015-01-01

    Objective In vivo Proton Magnetic Resonance Spectroscopy (1H-MRS) can be used to evaluate the levels of specific neurochemical biomarkers of pathological mechanisms in the brain. Methods We conducted T2-Weighted Magnetic Resonance Imaging (MRI) and 1H-MRS with a 3.0-Tesla animal MRI system to investigate the early microstructural and metabolic profiles in vivo in the striatum of rats following carbon monoxide (CO) poisoning. Results Compared to baseline, we found significant cortical surface deformation, cerebral edema changes, which were indicated by the unclear gray/white matter border, and lateral ventricular volume changes in the brain. A significant reduction in the metabolite to total creatine (Cr) ratios of N-acetylaspartate (NAA) was observed as early as 1 h after the last CO administration, while the lactate (Lac) levels increased marginally. Both the Lac/Cr and NAA/Cr ratios leveled off at 6 h and showed no subsequent significant changes. In addition, compared to the control, the choline (Cho)/Cr ratio was slightly reduced in the early stages and significantly increased after 6 h. In addition, a pathological examination revealed mild cerebral edema on cessation of the insult and more severe cerebral injury after additional CO poisoning. Conclusion The present study demonstrated that 1H-MRS of the brain identified early metabolic changes after CO poisoning. Notably, the relationship between the increased Cho/Cr ratio in the striatum and delayed neuropsychologic sequelae requires further research.

  20. The classification of benign and malignant human prostate tissue by multivariate analysis of {sup 1}H magnetic resonance spectra

    Hahn, P.; Smith, I.; Leboldus, L.; Littman, C.; Somorjai, L.; Bezabeh, T. [Institute for Biodiagnostic, National Research Council, Manitoba (Canada)

    1998-04-01

    {sup 1}H magnetic resonance spectroscopy studies (360 MHz) were performed on specimens of benign (n = 66) and malignant (n = 21) human prostate tissue from 50 patients and the spectral data were subjected to multivariate analysis, specifically linear-discriminant analysis. On the basis of histopathological assessments, an overall classification accuracy of 96.6 % was achieved, with a sensitivity of 100 % and a specificity of 95.5 % in classifying benign prostatic hyperplasia from prostatic cancer. Resonances due to citrate, glutamate, and taurine were among the six spectral subregions identified by our algorithm as having diagnostic potential. Significantly higher levels of citrate were observed in glandular than in stromal benign prostatic hyperplasia (P < 0.05). This method shows excellent promise for the possibility of in vivo assessment of prostate tissue by magnetic resonance. (author)

  1. 1H-Magnetic resonance spectroscopy in Mb. Alzheimer's and MCI patients

    In this study a proton magnetic spectroscopy was conducted on 38 patients suffering from Alzheimer, 10 patients with MCI (mild cognitive impairment) and 21 elderly controls. The analyzed metabolites were N-acetyl-aspartate (NAA), creatine (Cr), choline (Cho) and myo-Inositol (Ins). 1H-MRS was conducted in the cingulated gyri and the centrum semiovale of 38 patients with AD, 10 patients with MCI and 21 elderly controls. A STEAM sequence was used at 1,5 Tesla. The values of NAA, Cho, Cr and Ins were measured and the ratios of NAA/Cr, NAA/Cho, Cho/Cr and Ins/Cr were statistically evaluated. The Ins/Cr Ratio in the posterior cingulated gyrus was significantly lower in the MCI group than in the DAT group (p=0,007), while the decrease of the Ins/Cr Ratio in the compared controls was not significant. The NAA/Cr ratio was not significantly different whether in patients with AD, MCI nor in the examined controls. NAA/Cho and Cho/Cr ratios were likewise not significantly different in the three groups. Our findings of an increased Ins/Cr Ratio in the AD group might indicate the beginning of glial activation in the posterior cingulated gyri. As the other examined ratios were not significantly different among the three groups, our patients may not have suffered significant neuronal loss yet. (author)

  2. Glutamatergic system dysfunction in schizophrenia. A proton magnetic resonance spectroscopy (1H MRS) study

    The present study was performed to determine whether there are any differences in metabolite levels as measured by 1 H MRS between chronic and first-episode schizophrenic patients. 17 patients with the diagnosis of chronic schizophrenia and 31 patients with first-episode schizophrenia (ICD-10) were included into the study. The patients were assessed by means of PANSS, CGI and Calgary scales.We also examined 13 healthy persons as control group. MRI and MRS procedures: Proton resonance spectroscopy was performed on a 1,5 MR scanner, PRESS sequence, TR=1500 ms, TE=35 ms, number of repetition=192 and included suppression of water by MOIST sequence. Each volume element (voxel) had dimension of 2x2x2 cm and was localised in the left frontal lobe, in the left temporal lobe and in left thalamus. Complex containing glutamine (Gln), glutamate (Glu) and gamma-aminobutyric acid (GABA) was measured. Ratios of metabolite to creatine and unsuppressed water signal were analysed. We didn't find any significant differences in Glx levels between chronic and first-episode patients and between chronic patients and controls in all studied regions.In the left temporal lobe Glx/Cr ratio was significantly higher in first-episode patients in comparison to controls.We observed significant positive correlation between Glx/Cr level in the left temporal lobe and CGI and PANSS-Negative scores, and negative correlation between Glx/H20 level in the left temporal lobe and PANSS-Positive score. Increased Glx level in the left temporal lobe in first-episode patients suggest that altered glutamatergic activity in this region is present at the onset of disease and doesn't progress over time. (author)

  3. 1H-magnetic resonance spectroscopy of vascular endothelial growth factor-induced neuroprotection following acute cerebral ischemia and reperfusion

    Li Yi; Haiou Zhang; Hao Lei; Li Wei

    2008-01-01

    BACKGROUND: It has become generally accepted that measuring N-acetyI-L-aspartic acid through the use of 1H-magnetic resonance spectroscopy (1H-MRS) could be used to evaluate neuronal injury. OBJECTIVE: To study metabolic changes of N-acetyl-L-aspanic acid surrounding the acute cerebral ischcmia area following vascular endothelial growth factor (VEGF) treatment using 1H-MRS imaging, and to evaluate the neuroprotective effects of VEGE.DESIGN, TIME AND SETTING: Randomly controlled animal study, according to one-factor analysis of variance, was performed at the Shenzhen Hospital of Peking University and State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences from August 2003 to December 2005.MATERIALS: Twelve healthy, adult, Sprague Dawley rats were used to establish an ischemia/reperfusion model through the use of middle cerebral artery occlusion. The 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. VEGF164 was purchased from Shenzhen Jingmei Bioengineering Co., Ltd. Titus ancsthesia machine was purchased from Draeger Medical AG & Co. KG.METHODS: The rats were randomly divided into model control (n = 6) and VEGF-injected (n = 6) groups. All animals received 60-minute middle cerebral artery occlusion and 24-hour repcrfusion. Lateral cerebral ventricle injection was performed by stereotaxic technique at respective time points. The VEGF group received 0. 1 μ g/μ L VEGF (5 μL), and the model group received the same amount of normal saline, once daily for 3 days.MAIN OUTCOME MEASURES: Metabolic changes of N-acetyl-L-aspartic acid and lactic acid following cerebral ischemia and reperfusion were detected using 1H-MRS, and the ischemic volume was measured.RESULTS: Twelve rats were included in the final analysis. =H-MRS results revealed that the ischemic volume increased in the control group compared with prior to injection (P < 0.01). In the

  4. IN VIVO 1H MAGNETIC RESONANCE SPECTROSCOPY IN EVALUATION OF HEPATOCELLULAR CARCINOMA AND ITS EARLY RESPONSE TO TRANSCATHETER ARTERIAL CHEMOEMBOLIZATION

    Bin Wu; Wei-jun Peng; Pei-jun Wang; Ya-jia Gu; Wen-tao Li; Liang-pin Zhou; Feng Tang; Guo-ming Zhong

    2006-01-01

    Objective To investigate the value of in vivo proton magnetic resonance spectroscopy (MRS) in the assessment of hepatocellular carcinoma (HCC) and monitor its metabolic change shortly after transcatheter arterial chemoembolization (TACE).Methods In this prospective study,28 consecutive patients with large HCC (≥3 cm in diameter) confirmed by fine needle aspiration biopsy were recruited.The 1H MRS of all hepatic lesions and some uninvolved liver parenchyma were performed with 1.5T whole body MR scanner.Among them,15 cases were evaluated again about one week after TACE.The main metabolites such as choline and lipid before and after interventional therapy were measured to assess the early response of the tumor.Results The technical success rate of 1H MRS in liver was high (33/41,80%),closely related to breath motion,location of lesion,and size of voxel.In spectra,the choline compound peak of HCC elevated compared with uninvolved liver parenchyma.After TACE,both the amplitude and the area of choline resonance peak significantly descended (choline-to-lipid ratios from 0.352±0.080 to 0.167±0.030,P=0.026;from 0.205±0.060 to 0.070±0.020,P=0.042,respectively);yet lipid resonance peak ascended.Conclusions In vivo 1H MRS is technically feasible for the evaluation of large focal hepatic lesions,however,the reproducibility and stability are not as good as routine MR scan.1H MRS can monitor the early stage metabolic changes of HCC after TACE but limitation like quantification still exists.

  5. Investigation of stroke in sickle cell disease by 1H nuclear magnetic resonance spectroscopy

    Localized proton nuclear magnetic resonance spectroscopy (MRS), obtained with stimulated echo and spin echo sequences, MR imaging (MRI) and MR angiography (MRA) were used to study the brain in 13 children and adolescents with sickle cell disease. Regions of interest (ROI) studied by MRS included regions appearing normal on MRI as well as regions showing complications of sickle cell disease, including focal deep white matter areas of high signal intensity (deep white matter ischemia, DWMI) seen on long TR images, focal atropic brain areas, and infarcts. The findings in these studies are summarized as follows: Normal-appearing regions on MRI have normal MRS. In ROI including small areas of DWMI, lactate elevation was not detected, but the levels of N-acetyl-aspartate (NAA) appeared slightly elevated. In areas of DWMI 1-2 cm in size, reduced blood flow could be seen on MRA and lactate elevation could be detected with MRS. When blood flow to a DWMI region was normal, NAA was reduced and there was little lactate elevation, as cell death had already occurred. ROI consisting of atrophic tissue had reduced NAA levels but total creatine levels were not changed. Sometimes lipids, presumably from broken cell membrane, could be detected. In regions of past massive stroke, all metabolites were absent except for small amounts of lactate or lipids. (orig.)

  6. Application of cryoprobe 1H nuclear magnetic resonance spectroscopy and multivariate analysis for the verification of corsican honey.

    Donarski, James A; Jones, Stephen A; Charlton, Adrian J

    2008-07-23

    Proton nuclear magnetic resonance spectroscopy ((1)H NMR) and multivariate analysis techniques have been used to classify honey into two groups by geographical origin. Honey from Corsica (Miel de Corse) was used as an example of a protected designation of origin product. Mathematical models were constructed to determine the feasibility of distinguishing between honey from Corsica and that from other geographical locations in Europe, using (1)H NMR spectroscopy. Honey from 10 different regions within five countries was analyzed. (1)H NMR spectra were used as input variables for projection to latent structures (PLS) followed by linear discriminant analysis (LDA) and genetic programming (GP). Models were generated using three methods, PLS-LDA, two-stage GP, and a combination of PLS and GP (PLS-GP). The PLS-GP model used variables selected by PLS for subsequent GP calculations. All models were generated using Venetian blind cross-validation. Overall classification rates for the discrimination of Corsican and non-Corsican honey of 75.8, 94.5, and 96.2% were determined using PLS-LDA, two-stage GP, and PLS-GP, respectively. The variables utilized by PLS-GP were related to their (1)H NMR chemical shifts, and this led to the identification of trigonelline in honey for the first time. PMID:18564849

  7. Proton magnetic resonance spectroscopy ((1H-MRS reveals geniculocalcarine and striate area degeneration in primary glaucoma.

    Yan Zhang

    Full Text Available BACKGROUND: Glaucoma is a collection of neurodegenerative diseases that affect both the retina and the central visual pathway. We investigated whether metabolites' concentrations changed in the geniculocalcarine (GCT and the striate area of occipital lobe by proton magnetic resonance spectroscopy ((1H-MRS, suggesting neurodegeneration of the central visual pathway in primary glaucoma. METHODOLOGY/PRINCIPAL FINDINGS: 20 patients with glaucoma in both eyes were paired with 20 healthy volunteers in same gender and an age difference less than 3 years. All the participants were examined by MR imaging including T1 Flair, T2 FSE and (1H-MRS. The T1 intensity and T2 intensity of their GCTs and striate areas were measured. The ratio of N-acetylaspartate (NAA/Creatine (Cr, Choline (Cho/Cr, glutamine and glutamate (Glx/Cr were derived by multi-voxels (1H-MRS in the GCT and the striate area of each brain hemisphere. The T1 intensity and T2 intensity had no difference between the groups. Significant decreases in NAA/Cr and Cho/Cr but no difference in Glx/Cr was found between the groups in both the GCT and the striate area. CONCLUSIONS/SIGNIFICANCE: Primary glaucoma affects metabolites' concentrations in the GCT and the striate area suggesting there is ongoing neurodegenerative process.

  8. Establishing 1H nuclear magnetic resonance based metabonomics fingerprinting profile for spinal cord injury: a pilot study

    JIANG Hua; PENG Jin; ZHOU Zhi-yuan; DUAN Yu; CHEN Wei; CAI Bin; YANG Hao; ZHANG Wei

    2010-01-01

    Background Spinal cord injury (SCI) is a complex trauma that consists of multiple pathological mechanisms involving cytotoxic, oxidation stress and immune-endocrine. This study aimed to establish plasma metabonomics fingerprinting atlas for SCI using 1H nuclear magnetic resonance (NMR) based metabonomics methodology and principal component analysis techniques.Methods Nine Sprague-Dawley (SD) male rats were randomly divided into SCI, normal and sham-operation control groups. Plasma samples were collected for 1H NMR spectroscopy 3 days after operation. The NMR data were analyzed using principal component analysis technique with Matlab software.Results Metabonomics analysis was able to distinguish the three groups (SCI, normal control, sham-operation). The fingerprinting atlas indicated that, compared with those without SCI, the SCI group demonstrated the following characteristics with regard to second principal component: it is made up of fatty acids, myc-inositol, arginine, very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), triglyceride (TG), glucose, and 3-methyl-histamine.Conclusions The data indicated that SCI results in several significant changes in plasma metabolism early on and that a metabonomics approach based on 1H NMR spectroscopy can provide a metabolic profile comprising several metabolite classes and allow for relative quantification of such changes. The results also provided support for further development and application of metabonomics technologies for studying SCI and for the utilization of multivariate models for classifying the extent of trauma within an individual.

  9. 1H Nuclear Magnetic Resonance Relaxometry Study of Water State in Milk Protein Mixtures

    Le Dean, A.; Mariette, F.; Marin, M

    2004-01-01

    1H NMR signal was used to characterize highly hydrated milk protein dispersions (3-20% dry matter) with various micellar casein concentrations (3-15%), whey protein concentrations (0-3%), lactose concentrations (0-7.5%), CaCl2 concentrations (0-2 mM), and pH (6.2-6.6). The results showed the predominant effect of micellar casein concentration on water state and were consistent with the three-site relaxation model in the absence of lactose. The relaxation rates observed for these dispersions w...

  10. 1H and 19F nuclear magnetic resonance microimaging of water and chemical distribution in soil columns.

    Simpson, Myrna J; Simpson, André J; Gross, Dieter; Spraul, Manfred; Kingery, William L

    2007-07-01

    Nuclear magnetic resonance (NMR) microimaging is a noninvasive and nondestructive technique that has great potential for the study of soil processes. Hydrogen-1 NMR microimaging techniques were used to examine the distribution of water in four different soil cores. Fluorine-19 NMR microimaging is also used to study the transport of three model contaminants (hexafluorobenzene, sodium fluoride, and trifluralin) in soil columns. The 1H water distribution studies demonstrate that NMR microimaging can provide unique detail regarding the nature and location of water in soils. Image distortion (magnetic susceptibility) was observed for soil samples low in water (20-28% by weight) and that contained an iron content of 0.73 to 0.99%. Highly resolved images were obtained for the organic-rich soil (Croatan sample) and also facilitated the analysis of bound and unbound soil water through varying spin echo times. The contaminant studies with 19F NMR demonstrated that preferential flow processes can be observed in soil cores in as little as 16 h. Studies with hexafluorobenzene produced the highest quality images whereas the definition decreased over time with both trifluralin and sodium fluoride as the compounds penetrated the soil. Nonetheless, both 1H and 19F NMR microimaging techniques demonstrate great promise for studying soil processes. PMID:17665672

  11. Stereoelectronic effects on 1H nuclear magnetic resonance chemical shifts in methoxybenzenes

    Lambert, Maja; Olsen, Lars; Jaroszewski, Jerzy W

    2006-01-01

    differences are due to different conformational behavior of the OH and OCH3 groups; while the ortho-disubstituted OH group remains planar in polyphenols due to hydrogen bonding and conjugative stabilization, the steric congestion in ortho-disubstituted anisoles outweighs the conjugative effects and forces the......Investigation of all O-methyl ethers of 1,2,3-benzenetriol and 4-methyl-1,2,3-benzenetriol (3-16) by 1H NMR spectroscopy and density-functional calculations disclosed practically useful conformational effects on 1H NMR chemical shifts in the aromatic ring. While the conversion of phenol (2) to...... Ar-OCH3 torsion out of the ring plane, resulting in large stereoelectronic effects on the chemical shift of Hpara. Conformational searches and geometry optimizations for 3-16 at the B3LYP/6-31G** level, followed by B3LYP/6-311++G(2d,2p) calculations for all low-energy conformers, gave excellent...

  12. Non-invasive assessment of hepatic fat accumulation in chronic hepatitis C by {sup 1}H magnetic resonance spectroscopy

    Krssak, Martin [Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna (Austria); Hofer, Harald [Department of Internal Medicine III, Division of Gastroenterology and Hepatology, Medical University of Vienna (Austria); Wrba, Fritz [Department of Clinical Pathology, Medical University of Vienna (Austria); Meyerspeer, Martin [MR Centre-of-Excellence, Department of Radiodiagnostics, Medical University of Vienna (Austria); Center for Biomedical Engineering and Physics, Medical University of Vienna (Austria); Brehm, Attila [Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna (Austria); Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center of Diabetes Research and Department of Medicine/Metabolic Diseases, Heinrich Heine University, Duesseldorf (Germany); Lohninger, Alfred [Department of Medical Chemistry, Center for Physiology and Pathophysiology, Medical University of Vienna (Austria); Steindl-Munda, Petra [Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna (Austria); MR Centre-of-Excellence, Department of Radiodiagnostics, Medical University of Vienna (Austria); Moser, Ewald [MR Centre-of-Excellence, Department of Radiodiagnostics, Medical University of Vienna (Austria); Center for Biomedical Engineering and Physics, Medical University of Vienna (Austria); Ferenci, Peter [Department of Internal Medicine III, Division of Gastroenterology and Hepatology, Medical University of Vienna (Austria); Roden, Michael, E-mail: michael.roden@ddz.uni-duesseldorf.d [Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna (Austria); Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center of Diabetes Research and Department of Medicine/Metabolic Diseases, Heinrich Heine University, Duesseldorf (Germany)

    2010-06-15

    Background: Liver biopsy is the standard method for diagnosis of hepatic steatosis, but is invasive and carries some risk of morbidity. Aims and methods: Quantification of hepatocellular lipid content (HCL) with non-invasive single voxel {sup 1}H magnetic resonance spectroscopy (MRS) at 3 T was compared with histological grading and biochemical analysis of liver biopsies in 29 patients with chronic hepatitis C. Body mass index, indices of insulin resistance (homeostasis model assessment index, HOMA-IR), serum lipids and serum liver transaminases were also quantified. Results: HCL as assessed by {sup 1}H MRS linearly correlated (r = 0.70, p < 0.001) with histological evaluation of liver biopsies and was in agreement with histological steatosis staging in 65% of the patients. Biochemically assessed hepatic triglyceride contents correlated with HCL measured with {sup 1}H MRS (r = 0.63, p < 0.03) and allowed discriminating between none or mild steatosis versus moderate or severe steatosis. Patients infected with hepatitis C virus genotype 3 had a higher prevalence of steatosis (62%) which was not explained by differences in body mass or whole body insulin resistance. When these patients were excluded from correlation analysis, hepatic fat accumulation positively correlated with insulin resistance in the remaining hepatitis C patients (HCL vs. HOMA-IR, r = 0.559, p < 0.020, n = 17). Conclusion: Localized {sup 1}H MRS is a valid and useful method for quantification of HCL content in patients with chronic hepatitis C and can be easily applied to non-invasively monitoring of steatosis during repeated follow-up measurements in a clinical setting.

  13. (1)H-Nuclear Magnetic Resonance-Based Plasma Metabolic Profiling of Dairy Cows with Fatty Liver.

    Xu, Chuang; Sun, Ling-Wei; Xia, Cheng; Zhang, Hong-You; Zheng, Jia-San; Wang, Jun-Song

    2016-02-01

    Fatty liver is a common metabolic disorder of dairy cows during the transition period. Historically, the diagnosis of fatty liver has involved liver biopsy, biochemical or histological examination of liver specimens, and ultrasonographic imaging of the liver. However, more convenient and noninvasive methods would be beneficial for the diagnosis of fatty liver in dairy cows. The plasma metabolic profiles of dairy cows with fatty liver and normal (control) cows were investigated to identify new biomarkers using (1)H nuclear magnetic resonance. Compared with the control group, the primary differences in the fatty liver group included increases in β-hydroxybutyric acid, acetone, glycine, valine, trimethylamine-N-oxide, citrulline, and isobutyrate, and decreases in alanine, asparagine, glucose, γ-aminobutyric acid glycerol, and creatinine. This analysis revealed a global profile of endogenous metabolites, which may present potential biomarkers for the diagnosis of fatty liver in dairy cows. PMID:26732447

  14. Integration of 3D 1H-magnetic resonance spectroscopy data into neuronavigation systems for tumor biopsies

    Kanberoglu, Berkay; Moore, Nina Z.; Frakes, David; Karam, Lina J.; Debbins, Josef P.; Preul, Mark C.

    2013-03-01

    Many important applications in clinical medicine can benefit from the fusion of spectroscopy data with anatomical images. For example, the correlation of metabolite profiles with specific regions of interest in anatomical tumor images can be useful in characterizing and treating heterogeneous tumors that appear structurally homogeneous. Such applications can build on the correlation of data from in-vivo Proton Magnetic Resonance Spectroscopy Imaging (1HMRSI) with data from genetic and ex-vivo Nuclear Magnetic Resonance spectroscopy. To establish that correlation, tissue samples must be neurosurgically extracted from specifically identified locations with high accuracy. Toward that end, this paper presents new neuronavigation technology that enhances current clinical capabilities in the context of neurosurgical planning and execution. The proposed methods improve upon the current state-of-the-art in neuronavigation through the use of detailed three dimensional (3D) 1H-MRSI data. MRSI spectra are processed and analyzed, and specific voxels are selected based on their chemical contents. 3D neuronavigation overlays are then generated and applied to anatomical image data in the operating room. Without such technology, neurosurgeons must rely on memory and other qualitative resources alone for guidance in accessing specific MRSI-identified voxels. In contrast, MRSI-based overlays provide quantitative visual cues and location information during neurosurgery. The proposed methods enable a progressive new form of online MRSI-guided neuronavigation that we demonstrate in this study through phantom validation and clinical application.

  15. 1H and 31P magnetic resonance spectroscopic imaging of white matter signal hyperintensity areas in elderly subjects

    White matter signal hyperintensities (WMSH) are commonly seen on MRI of elderly subjects. The purpose of this study was to characterize metabolic changes in the white matter of elderly subjects with extensive WMSH. We used water-suppressed proton (1H) magnetic resonance spectroscopic imaging (MRSI) to compare six subjects with extensive WMSH with eight age-matched elderly subjects with minimal or absent WMSH, and phosphorus (31P) MRSI to compare nine subjects with extensive WMSH and seven age-matched elderly subjects without extensive WMSH. Relative to region-matched tissue in elderly controls, extensive WMSH were associated with increased signal from choline-containing metabolites, no significant change of signal from N-acetylaspartate, and a trend to a decreased phosphomonoester (PME) resonance. These findings suggest that WMSH may be associated with an alteration of brain myelin phospholipids in the absence of axonal damage. There were no differences in energy phosphates, consistent with lack of ongoing brain ischemia. Within the group with extensive WMSH, PME resonance measures were significantly lower in WMSH than in contralateral normal-appearing white matter. These results provide information on pathophysiology of WMSH and a basis for comparison with WMSH in Alzheimer's disease, vascular dementia, multiple sclerosis, and other diseases. (orig.). With 4 figs., 4 tabs

  16. 1H Nuclear Magnetic Resonance (NMR) metabonomic study of breast cancer in Indian population

    Breast cancer is the most common cancer diagnosed in women worldwide with over 1.3 million new cases per year. Recently it has been observed that breast cancer is increasing very rapidly in low income countries including India. Lipids not only play very important and vital role of prime structural component in human body they are also important functional components in cellular metabolism. Transformation from benign to malignant tissue involves several biochemical processes and understanding these processes provides very useful insight related to cancer prognosis. Thus study of lipids becomes very important and NMR spectroscopy is one of the techniques which can be utilized to identifying all lipid components simultaneously. The tissue specimens (35, benign 20 and malignant 15; patient age group 47 yrs) were collected after breast surgeries and were snap frozen in liquid nitrogen. Part of all tissues was sent for routine histopathology. Lipid extraction was performed by Folch method (Folch, 1957) using cholesterol and methanol (2:1 ratio). The NMR spectra of the extracted lipids were recorded immediately after the sample preparation. All NMR experiments were performed on a Bruker Avance 800 MHz spectrometer. 1H NMR analysis of lipid extract of breast tissue in Indian population shows there is significant elevation of phosphotidycholine, plasmalogen and esterified cholesterol with decrease in triacylglycerol in cancer breast compared to benign tissue implying that their metabolism is definitely altered during carcinogenesis. This study analyzes the role of NMR as an additional diagnostic tool on the basis of examination of lipid extract. (author)

  17. ~1H nuclear magnetic resonance-based metabolomics reveals sex-specific metabolic changes of gastrodin intervention in rats

    Xin; Li; Yuan-Wei; Jia; Jun-Song; Wang; Ming-Hua; Yang; Kelvin; D.G.Wang; Ling-Yi; Kong

    2014-01-01

    Objective:To explore~1H nuclear magnetic resonance-based metabolomics on sex-specific metabolic changes of gastrodin intervention in rats.Methods:In this research,~1H NMR-based metabolomics was used for the first time to investigate metabolic changes following chronic intervention with gastrodin in rats.Results:24 endogenous metabolites were identified.Body weight.daily diet and the total volume of urine in in each day of each rat were measured synchronously.Modifications in 12 metabolites were observsd following gastrodin intervention,indicating gastrodin-induced alterations in carbohydrate and energy metabolism.Interestingly,these metabolic changes were not totally identical in female and male rats.Some metabolic changes arising from gastrodin intervention showed sexual dimorphism including LDL/VLDL and lactate which were on the decrease in the female but on the increase in the male,together with arginine/ornithine,creatine,and glycerol which were on the increase in the female but on the decrease in the male.While the decrease in pyruvate,succinate and glutamate was only shown in the male and the increase in valine,α-ketoglutarate and glucose was only in the female.Conclusions:This resesrch shows the sex-specific metabolic response to GAS intervention,weather GAS is a healthy dietary supplement for the male merits further investigation

  18. A program for semi-automatic sequential resonance assignments in protein 1H nuclear magnetic resonance spectra

    Billeter, M.; Basus, V. J.; Kuntz, I. D.

    A new approach to the sequential resonance assignment of protein 1H NMR spectra based on a computer program is presented. Two main underlying concepts were used in the design of this program. First, it considers at any time all possible assignments that are consistent with the currently available data. If new information is added then assignments that have become inconsistent are eliminated. Second, the process of the assignment is split into formal steps that follow strictly from the available data and steps that involve the interpretation of ambiguous NMR data. The first kind of step is safe in the sense that it never leads to false assignments provided that the input does not contain any error; these steps are executed automatically by the program when the input files are read and whenever new data have been entered interactively. The second kind of step is left to the user: An interactive dialog provides detailed information on the current situation of the assignment and indicates what kind of new data would be most promising for further assignment. The user then provides new data to the program and restarts the automatic part which will attempt to draw logical conclusions from the joint use of the new data and the earlier available information and will eliminate assignments that have become inconsistent. Results of test problems using simulated NMR data for proteins consisting of up to 99 residues as well as the application of the program to obtain the complete assignment of α-bungarotoxin, a 74-residue snake neurotoxin, are reported.

  19. In vivo research in astrocytoma cell proliferation with {sup 1}H-magnetic resonance spectroscopy: correlation with histopathology and immunohistochemistry

    Chen, Jun; Li, Tao; Chen, Xi-Lan [Renmin Hospital of Wuhan University, Department of Radiology, Wuhan, Hubei Province (China); Huang, Shu-Lan [Renmin Hospital of Wuhan University, Department of Neurosurgery, Wuhan, Hubei Province (China)

    2006-05-15

    Assessment of brain tumor proliferative potential provides important prognostic information that supplements standard histopathologic grading. Proton magnetic resonance spectroscopy ({sup 1}H-MRS) gives completely different information, relating to cell membrane proliferation, neuronal damage, energy metabolism and necrotic transformation of brain or tumor tissues. The aim of this study was to investigate the relationship between {sup 1}H-MRS and tumor proliferative potential in astrocytomas. We studied 34 patients with histologically verified astrocytomas using the {sup 1}H-MRS protocol following routine MRI preoperatively. The tumor in 26 of these patients was classified as grade I/II (low grade), and the tumor in the remaining patients as grade III/IV (high grade) according to the World Health Organization classification criteria of nervous system tumors (2000). The tumor in 21 patients was homogeneous astrocytoma, and of these 17 were classified as low grade and 4 as high grade. Expression of proliferating cell nuclear antigen (PCNA) was determined immunohistochemically using streptavidin-biotin-peroxidase complex (SP) staining. The ratios of choline (Cho) to N-acetylaspartate (NAA) and Cho to creatine (Cr) in those with high-grade astrocytomas (n=4) were significantly higher than in those with low-grade astrocytomas (n=17) (t=2.899, P=0.009; t=3.96, P=0.001, respectively), and were found to be significantly correlated with the expression of PCNA in 21 patients with homogeneous astrocytomas (r=0.455, P=0.038; r=0.633, P=0.002, respectively). (orig.)

  20. Bevacizumab impairs oxidative energy metabolism and shows antitumoral effects in recurrent glioblastomas: a 31P/1H MRSI and quantitative magnetic resonance imaging study

    HATTINGEN, ELKE; Jurcoane, Alina; Bähr, Oliver; Rieger, Johannes; Magerkurth, Jörg; Anti, Sandra; Steinbach, Joachim P.; Pilatus, Ulrich

    2011-01-01

    Bevacizumab shows unprecedented rates of response in recurrent glioblastomas (GBM), but the detailed mechanisms are still unclear. We employed in vivo magnetic resonance spectroscopic imaging (MRSI) and quantitative magnetic resonance imaging to investigate whether bevacizumab alters oxygen and energy metabolism and whether this effect has antitumoral activity in recurrent GBM. 31P and 1H MRSI, apparent diffusion coefficient (ADC), and high-resolution T2 and T2′ mapping (indirect marker of ox...

  1. Evaluation of invasiveness of astrocytoma using {sup 1}H-magnetic resonance spectroscopy: correlation with expression of matrix metalloproteinase-2

    Zhang, Kai; Li, Chuanfu; Ma, Xiangxing; Meng, Xiangshui; Feng, Dechao [Shandong University, Department of Radiology, Qilu Hospital, Jinan (China); Liu, Ying [Shandong University, Department of Radiology, Qilu Hospital, Jinan (China); Anhui Provincial Hospital, MRI Department, Hefei (China); Li, Li [Shandong University, Department of Pathology, Qilu Hospital, Jinan (China)

    2007-11-15

    Even low-grade astrocytomas infiltrate the entire brain, a feature that precludes their successful therapy. So to assess the invasive potential of astrocytoma is very important. The aim of this study was determine whether there is a significant correlation between the results of {sup 1}H-magnetic resonance spectroscopy ({sup 1}H-MRS) and tumor invasive potential of astrocytoma, which is reflected by expression of matrix metalloproteinase-2 (MMP-2). The {sup 1}H-MRS spectra of 41 histologically verified astrocytomas were obtained on a 3-T MR scanner. According to the World Health Organization classification criteria for central nervous system tumors, there were 16 low-grade astrocytomas (2 pilocytic astrocytomas, 14 grade II astrocytomas) and 25 high-grade astrocytomas (5 anaplastic astrocytomas, 20 glioblastomas).The choline/N-acetylaspartate (Cho/NAA) and choline/creatine (Cho/Cr) ratios were calculated. Of the 41 astrocytomas, 19 (8 low-grade and 11 high-grade) were analyzed immunohistochemically. Expression of MMP-2 was determined using streptavidin-peroxidase complex (SP) staining which was quantified by calculating its calibrated opacity density (COD) using an image analysis system. The correlations between metabolite ratios and the quantitative data from the immunohistochemical tests in the 19 astrocytomas were determined. The Cho/NAA and Cho/Cr ratios of high-grade astrocytoma were both significantly greater than those of low-grade astrocytoma (t = -6.222, P = 0.000; t = -6.533, P = 0.000, respectively). MMP-2 COD values of high-grade astrocytomas were also significantly greater than those of low-grade astrocytomas (t = -5.892, P = 0.000). There were strong positive correlations between Cho/NAA ratio and MMP-2 COD (r = 0.669, P = 0.002), and between Cho/Cr ratio and MMP-2 COD (r = 0.689, P = 0.001). {sup 1}H-MRS is helpful in evaluating the invasiveness of astrocytomas and predicting prognosis preoperatively by determining the Cho/NAA and Cho/Cr ratios

  2. 1H magnetic resonance spectroscopy of urine for the assessment of renal dysfunction in healthy pregnant women

    Background. Pregnancy is associated with adaptive alterations affecting almost all organs and systems of the female body and is also a time when pathologies appear which would otherwise remain asymptomatic for many years. 1H Magnetic Resonance Spectroscopy (1H-MRS) of urine, a modern diagnostic method, can disclose discrete changes in organ function. It seemed interesting to search for pregnancy-dependent renal pathology in healthy women and thus prognosticate progression to overt disease after pregnancy. Objectives. To determine whether physiological pregnancy is accompanied by alterations in renal structures detectable by 1H-MRS of urine and to assess the type and reversibility of alterations. Material and Methods. Eighty women were enrolled in two groups: a study group (B) consisting of 40 healthy pregnant women and a control group (K) of 40 healthy nulligravida women. Enrollment criteria included normal health status, unrevealing physical and gynecological examination, and normal results of laboratory tests (complete blood count, urea, creatinine, uric acid, urinalysis). MRS of urine and laboratory tests were done in group B during each trimester (B1, B2, and B3, i.e. the 1st, 2nd, and 3rd trimesters, respectively) and six weeks after delivery (BP). In group K, the tests were done only once. The spectra were processed with MestReC software and then multidimensional statistical analysis using Unscrambler software was performed. The results were presented as the distribution of the variables in multidimensional space. Results. The patterns in multidimensional space revealed a clustering of points when comparing the first and third trimesters of pregnancy and comparing the third trimester and the healthy non-pregnant women. Also, a partial clustering of points comparing healthy non-pregnant and pregnant women after the puerperium was noticeable. Conclusions. Differences in 1H-MRS profiles of urine between healthy pregnant and non-pregnant women reflect alterations

  3. Evaluation of invasiveness of astrocytoma using 1H-magnetic resonance spectroscopy: correlation with expression of matrix metalloproteinase-2

    Even low-grade astrocytomas infiltrate the entire brain, a feature that precludes their successful therapy. So to assess the invasive potential of astrocytoma is very important. The aim of this study was determine whether there is a significant correlation between the results of 1H-magnetic resonance spectroscopy (1H-MRS) and tumor invasive potential of astrocytoma, which is reflected by expression of matrix metalloproteinase-2 (MMP-2). The 1H-MRS spectra of 41 histologically verified astrocytomas were obtained on a 3-T MR scanner. According to the World Health Organization classification criteria for central nervous system tumors, there were 16 low-grade astrocytomas (2 pilocytic astrocytomas, 14 grade II astrocytomas) and 25 high-grade astrocytomas (5 anaplastic astrocytomas, 20 glioblastomas).The choline/N-acetylaspartate (Cho/NAA) and choline/creatine (Cho/Cr) ratios were calculated. Of the 41 astrocytomas, 19 (8 low-grade and 11 high-grade) were analyzed immunohistochemically. Expression of MMP-2 was determined using streptavidin-peroxidase complex (SP) staining which was quantified by calculating its calibrated opacity density (COD) using an image analysis system. The correlations between metabolite ratios and the quantitative data from the immunohistochemical tests in the 19 astrocytomas were determined. The Cho/NAA and Cho/Cr ratios of high-grade astrocytoma were both significantly greater than those of low-grade astrocytoma (t = -6.222, P = 0.000; t = -6.533, P = 0.000, respectively). MMP-2 COD values of high-grade astrocytomas were also significantly greater than those of low-grade astrocytomas (t = -5.892, P 0.000). There were strong positive correlations between Cho/NAA ratio and MMP-2 COD (r = 0.669, P = 0.002), and between Cho/Cr ratio and MMP-2 COD (r = 0.689, P = 0.001). 1H-MRS is helpful in evaluating the invasiveness of astrocytomas and predicting prognosis preoperatively by determining the Cho/NAA and Cho/Cr ratios. (orig.)

  4. Brain temperature measured by {sup 1}H-magnetic resonance spectroscopy in acute and subacute carbon monoxide poisoning

    Fujiwara, Shunrou; Nishimoto, Hideaki; Murakami, Toshiyuki; Ogawa, Akira; Ogasawara, Kuniaki [Iwate Medical University, Department of Neurosurgery, Morioka, Iwate (Japan); Yoshioka, Yoshichika [Osaka University, Laboratory of Biofunctional Imaging, WPI Immunology Frontier Research Center, Osaka (Japan); Matsuda, Tsuyoshi [MR Applications and Workflow Asia Pacific, GE Healthcare Japan, Tokyo (Japan); Beppu, Takaaki [Iwate Medical University, Department of Neurosurgery, Morioka, Iwate (Japan); Iwate Medical University, Department of Hyperbaric Medicine, Iwate (Japan)

    2016-01-15

    Brain temperature (BT) is associated with the balance between cerebral blood flow and metabolism according to the ''heat-removal'' theory. The present study investigated whether BT is abnormally altered in acute and subacute CO-poisoned patients by using {sup 1}H-magnetic resonance spectroscopy (MRS). Eight adult CO-poisoned patients underwent 3-T magnetic resonance imaging in the acute and subacute phases after CO exposure. MRS was performed on deep cerebral white matter in the centrum semiovale, and MRS-based BT was estimated by the chemical shift difference between water and the N-acetyl aspartate signal. We defined the mean BT + 1.96 standard deviations of the BT in 15 healthy controls as the cutoff value for abnormal BT increases (p < 0.05) in CO-poisoned patients. BT of CO-poisoned patients in both the acute and subacute phases was significantly higher than that of the healthy control group. However, BT in the subacute phase was significantly lower than in the acute phase. On the other hand, no significant difference in body temperature was observed between acute and subacute CO-poisoned patients. BT weakly correlated with body temperature, but this correlation was not statistically significant (rho = 0.304, p = 0.2909). The present results suggest that BT in CO-poisoned patients is abnormally high in the acute phase and remains abnormal in the subacute phase. BT alteration in these patients may be associated with brain perfusion and metabolism rather than other factors such as systemic inflammation and body temperature. (orig.)

  5. Brain temperature measured by 1H-magnetic resonance spectroscopy in acute and subacute carbon monoxide poisoning

    Brain temperature (BT) is associated with the balance between cerebral blood flow and metabolism according to the ''heat-removal'' theory. The present study investigated whether BT is abnormally altered in acute and subacute CO-poisoned patients by using 1H-magnetic resonance spectroscopy (MRS). Eight adult CO-poisoned patients underwent 3-T magnetic resonance imaging in the acute and subacute phases after CO exposure. MRS was performed on deep cerebral white matter in the centrum semiovale, and MRS-based BT was estimated by the chemical shift difference between water and the N-acetyl aspartate signal. We defined the mean BT + 1.96 standard deviations of the BT in 15 healthy controls as the cutoff value for abnormal BT increases (p < 0.05) in CO-poisoned patients. BT of CO-poisoned patients in both the acute and subacute phases was significantly higher than that of the healthy control group. However, BT in the subacute phase was significantly lower than in the acute phase. On the other hand, no significant difference in body temperature was observed between acute and subacute CO-poisoned patients. BT weakly correlated with body temperature, but this correlation was not statistically significant (rho = 0.304, p = 0.2909). The present results suggest that BT in CO-poisoned patients is abnormally high in the acute phase and remains abnormal in the subacute phase. BT alteration in these patients may be associated with brain perfusion and metabolism rather than other factors such as systemic inflammation and body temperature. (orig.)

  6. Metabolic Alterations of the Zebrafish Brain after Acute Alcohol Treatment by 1H Nuclear Magnetic Resonance Spectroscopy

    Dong-Cheol Woo

    2013-01-01

    Full Text Available The purpose of this study is to investigate the metabolic alterations associated with acute alcohol treatment in zebrafish by 1H nuclear magnetic resonance spectroscopy (NMRS. The brain metabolism of zebrafish was investigated after acute alcohol treatment (one-hour long exposure of adult fish to 0.00%, 0.25%, 0.50%, or 1.00% ethyl alcohol with whole brain extraction. The results of this study showed that glutamate (Glu was significantly decreased, scyllo-inositol (sIns showed a small apparent increase only in the highest acute treatment dose group, and myoinositol (mIns showed a significant decrease. [Glu]/[tCr] and [mIns]/[tCr] levels were significantly reduced regardless of the alcohol dose, and [sIns]/[tCr] was increased in the highest alcohol treatment dose group. The present NMR study revealed that specific metabolites, such as Glu and mIns, were substantially decreased in case of acute alcohol exposed zebrafish brain.

  7. 1H nuclear magnetic resonance-based metabolomics reveals sex-specific metabolic changes of gastrodin intervention in rats

    Xin Li; Yuan-Wei Jia; Jun-Song Wang; Ming-Hua Yang; Kelvin D G Wang; Ling-Yi Kong

    2014-01-01

    Objective:To explore1H nuclear magnetic resonance-based metabolomics on sex-specific metabolic changes of gastrodin intervention in rats.Methods:In this research,1HNMR-based metabolomics was used for the first time to investigate metabolic changes following chronic intervention with gastrodin in rats.Results:24 endogenous metabolites were identified.Body weight, daily diet and the total volume of urine in in each day of each rat were measured synchronously.Modifications in12 metabolites were observed following gastrodin intervention, indicating gastrodin-induced alterations in carbohydrate and energy metabolism.Interestingly, these metabolic changes were not totally identical in female and male rats.Some metabolic changes arising from gastrodin intervention showed sexual dimorphism includingLDL/VLDL and lactate which were on the decrease in the female but on the increase in the male, together with arginine/ornithine, creatine, and glycerol which were on the increase in the female but on the decrease in the male.While the decrease in pyruvate, succinate and glutamate was only shown in the male and the increase in valine,α-ketoglutarate, glycine and glucose was only in the female. Conclusions:This research shows the sex-specific metabolic response toGAS intervention, weatherGAS is a healthy dietary supplement for the male merits further investigation.

  8. Selective inversion of 1H resonances in solid-state nuclear magnetic resonance: Use of double-DANTE pulse sequence

    Mithu, Venus Singh; Tan, Kong Ooi; Madhu, P. K.

    2013-12-01

    We here present a method based on DANTE pulses and homonuclear dipolar decoupling scheme to invert selectively any desired resonance in a proton spin system under magic-angle spinning. Experimental results are reported on a sample of L-histidine·HCl·H2O at magic-angle spinning frequencies of 15 and 60 kHz. The results are also substantiated numerically.

  9. Conformational requirement of signal sequences functioning in yeast: Circular dichroism and 1H nuclear magnetic resonance studies of synthetic peptides

    Recently, the authors have designed a series of simplified artificial signal sequences and have shown that a proline residue in the signal sequence plays an important role in the secretion of human lysozyme in yeast, presumably by altering the conformation of the signal sequence. To elucidate the conformational requirement of the signal sequence in more detail, functional and nonfunctional signal sequences connected to the N-terminal five residues of mature human lysozyme were chemically synthesized and their conformations in a lipophilic environment analyzed by circular dichroism (CD) and 1H nuclear magnetic resonance (NMR) spectroscopy. The helix content of the peptides, including functional (L8, CL10) and nonfunctional (L8PL, L8PG, L8PL2) signal sequences, was estimated from CD spectra to be 40-50% and 60-70%, respectively, indicating that the helical structure is more abundant in the nonfunctional signal sequences. Two-dimensional NMR analyses in 50% TFE/H2O revealed that each peptide adopted a helical conformation throughout the sequence except for a few residues at the N- and C-termini. Furthermore, H-D exchange experiments indicated that the helical structure of the C-terminal region of the functional signal sequences (L8 and CL10) was less stable than that of the nonfunctional signal sequences (L8PL and L8PL2). On the basis of these results, a model was developed in which the functional signal sequence is inserted in the membrane with a helical conformation and the C-terminal helix unraveled in an extended conformational form through an interaction with the signal peptidase

  10. Metabolic profiles using (1)H-nuclear magnetic resonance spectroscopy in postpartum dairy cows with ovarian inactivity.

    Xu, Chuchu; Xia, Cheng; Sun, Yuhang; Xiao, Xinhuan; Wang, Gang; Fan, Ziling; Shu, Shi; Zhang, Hongyou; Xu, Chuang; Yang, Wei

    2016-10-01

    To understand the differences in metabolic changes between cows with ovarian inactivity and estrus cows, we selected cows at 60-90 days postpartum from an intensive dairy farm. According to clinical manifestations, B-ultrasound scan, rectal examination, 10 cows were assigned to the estrus group (A) and 10 to the ovarian inactivity group (B). All plasma samples were analyzed by (1)H-nuclear magnetic resonance spectroscopy to compare plasma metabolomic profiles between the groups. We used multivariate pattern recognition to screen for different metabolites in plasma of anestrus cows. Compared with normal estrous cows, there were abnormalities in 12 kinds of metabolites in postpartum cows with ovarian inactivity (|r|> 0.602), including an increase in acetic acid (r = -0.817), citric acid (r = -0.767), and tyrosine (r = -0.714), and a decrease in low-density lipoprotein (r = 0.820), very low-density lipoprotein (r = 0.828), lipids (r = 0.769), alanine (r = 0.816), pyruvate (r = 0.721), creatine (r = 0.801), choline (r = 0.639), phosphorylcholine (r = 0.741), and glycerophosphorylcholine (r = 0.881). These metabolites were closely related to abnormality of glucose, amino acid, lipoprotein and choline metabolism, which may disturb the normal estrus. The decrease in plasma creatine and the increase in tyrosine were new changes for ovarian inactivity of postpartum cows. The decrease in plasma creatine and choline and the increase in tyrosine and p-hydroxyphenylalanine in cows with ovarian inactivity provide new directions for research on the mechanism of ovarian inactivity in cows. PMID:27291083

  11. Quantitative analysis of retinol and retinol palmitate in vitamin tablets using 1H-nuclear magnetic resonance spectroscopy

    1H-NMR spectrometry was applied to the quantitative analysis of Vitamin A in four different types of vitamin tablets without any chromatographic purification or saponification. The experiment was performed analysing the H-15 resonance, which appears at δ 4.32 for retinol and δ 4.69 for retinol palmitate, well separated from other resonances in the 1H-NMR spectrum. Compounds were quantified using the relative ratio of the integral of the H-15 signal to that of a known amount of internal standard (200 μg/ml), anthracene. In order to evaluate the feasibility of avoiding the saponification of retinol palmitate in the preparation of samples, several solvents such as dimethylsulfoxide, n-hexane, methanol, water, and 0.1 M of HCl were tested as possible extraction solvents. Among these, dimethylsulfoxide showed the best yield of retinol palmitate. This method, using dimethylsulfoxide extraction and 1H-NMR, allows rapid and simple quantitation of retinol palmitate in tablets avoiding tedious saponification

  12. 1H-magnetic resonance spectroscopy screening for animals with acute cerebral infraction suitable for thrombolytic therapy

    Li Yi; Haiou Zhang; Hao Lei; Li Wei

    2007-01-01

    BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 'H-magnetic resonance spectroscopy ('H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke.OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 'H-MRS technology and investigate its adaptability. DESIGN: Randomly controlled animal study. SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science. MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260 - 300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 1H/kg urokinase was dissolved in 2 Ml saline and the operation lasted for 5 minutes. ②1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③The T2W image was conducted 24 hours after

  13. A retunable surface coil for high field 31P and 1H magnetic resonance evaluations of the living mouse leg

    This study presents a retunable surface coil that can be adjusted to at least two Larmor frequencies sequentially without the need to remove the coil from the magnet and while avoiding interference between channels. A prototype 1H/31P surface coil for the analysis of the in vivo mouse leg under electrical stimulation was designed for operation at 11.75 T. The coil has a high-quality factor of over 100 for both operational frequencies. To demonstrate the capabilities of this simple design, in vivo experiments were conducted to acquire high-resolution 1H images and 31P spectra of the C57BL/6 mouse leg, both with high temporal resolution. Proton diffusion tensor imaging was also performed to evaluate rodent skeletal muscle architecture. This design makes the acquisition of physiological data about both muscle structure and energetics (PCr, ATP and Pi) possible in a single experimental session

  14. High-speed magic angle spinning solid-state 1H nuclear magnetic resonance study of the conformation of gramicidin A in lipid bilayers.

    Bouchard, M.; Davis, J H; Auger, M.

    1995-01-01

    One- and two-dimensional solid-state 1H nuclear magnetic resonance spectra of gramicidin A incorporated in a dimyristoylphosphatidylcholine membrane have been obtained with use of high-speed magic angle spinning. By rotating the sample at 13 kHz, it is possible to observe signals in the 1H spectra between 6.0 and 9.0 ppm attributable to the aromatic protons of the tryptophan residues and the formyl group proton of gramicidin A. Two-dimensional solid-state COSY spectra provided information for...

  15. Analysis of Brain Metabolism by Proton-Magnetic-Resonance-Spectroscopy (1H-MRS) in Attention-Deficit/Hyperactivity Disorder Suggests a Generalized Differential Ontogenic Pattern from Controls

    Arcos-Burgos, Mauricio; Londoño, Ana C.; DAVID A PINEDA; Lopera, Francisco; Palacio, Juan David; Arbelaez, Andres; Acosta, Maria T.; Vélez, Jorge I.; Castellanos, Francisco Xavier; Muenke, Maximilian

    2012-01-01

    Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder of childhood. Preliminary studies with proton magnetic resonance spectroscopy (1HMRS) of the brain have reported differences in brain metabolite concentration-to-Cr ratios between individuals with ADHD and unaffected controls in several frontal brain regions including anterior cingulate cortex. Using multivoxel 1H-MRS, we compared 14 individuals affected with ADHD to 20 individuals without ADHD from the sam...

  16. Reduction in temporal N-acetylaspartate and creatine (or choline) ratio in temporal lobe epilepsy: does this 1H-magnetic resonance spectroscopy finding mean poor seizure control?

    Mendes-Ribeiro, J.; Soares, R.,; Simoes-Ribeiro, F.; Guimaraes, M

    1998-01-01

    BACKGROUND—Proton magnetic resonance spectroscopy (1H-MRS) is a potentially useful tool in the in vivo investigation of brain metabolites in intractable temporal lobe epilepsy (TLE). Focal N-acetylaspartatate (NAA) reductions have been correlated with mesial temporal sclerosis (MTS) in surgically resected epileptogenic foci.
OBJECTIVE—To evaluate the abnormalities in the metabolites NAA, creatine+ phosphocreatine (Cr), and choline containing compounds (Cho) in the tempora...

  17. 1H magnetic resonance spectroscopy and diffusion weighted imaging findings of medulloblastoma in 3.0T MRI A retrospective analysis of 17 cases

    Guangyao Wu; Haopeng Pang; Prasanna Ghimire; Guobing Liu

    2012-01-01

    1H magnetic resonance spectroscopy and diffusion weighted imaging features of the cerebellar vermis in 17 medulloblastoma patients were retrospectively analyzed, and 17 healthy volunteers were selected as controls. 1H magnetic resonance spectroscopy showed that in all 17 medulloblastoma patients, N-acetyl aspartate and creatine peaks were significantly decreased, the choline peak was significantly increased, and there was evidence of a myo-inositol peak. Further, 11 patients showed a low taurine peak at 3.4 ppm, five patients showed a lipid peak at 0.9–1.3 ppm, and three patients showed a negative lactic acid peak at 1.33 ppm. Compared with the control group, the ratios of N-acetyl aspartate/choline and N-acetyl aspartate/creatine were significantly decreased, and the ratio of choline/creatine was increased, in medulloblastoma patients. Diffusion weighted imaging displayed hyperintensity and decreased apparent diffusion coefficient in medulloblastoma patients. These findings indicate that 1H magnetic resonance spectroscopy and diffusion weighted imaging are useful for qualitative diagnosis of medulloblastoma.

  18. Proton magnetic resonance spectroscopy (1H MRS) of human brain tumours: assessment of differences between tumour types and its applicability in brain tumour categorization

    Our objective was to evaluate the usefulness of proton magnetic resonance spectroscopy (1H MRS) in categorizing brain tumours. In vivo single-voxel 1H MRS at an echo time of 136 ms was performed in 108 patients with brain neoplasms that included 29 meningiomas (MEN), 15 low-grade astrocytomas (LGA), 12 anaplastic astrocytomas (AA), 25 glioblastomas (GBM) and 27 metastases (MET). Time-domain fitted areas of nine resonances were evaluated in all spectra. Twenty-five additional tumours were prospectively included as independent test set. Differences in at least two resonances were found in all pairwise comparisons of tumour groups except in GBM vs MET. Large lipid resonance at 1.30 ppm was found to be characteristic of GBM and MET, and alanine was characteristic of MEN. Significant differences were found between LGA and AA in choline-containing compounds and total creatine resonances. When implemented in a stepwise algorithm, these findings correctly classified 84% (21 of 25) tumours in the independent test set. Some additional utility was found in glycine/myo-inositol at 3.55 ppm for bilateral differentiation between GBM and MET (9 of 11, 82% correct classification in the test set). 1H MRS provides useful information to categorize the most common brain tumours that can be implemented in clinical practice with satisfactory results. (orig.)

  19. Quantitative {sup 1}H and hyperpolarized {sup 3}He magnetic resonance imaging: Comparison in chronic obstructive pulmonary disease and healthy never-smokers

    Owrangi, Amir M., E-mail: aowrangi@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Graduate Program in Biomedical Engineering, The University of Western Ontario, London (Canada); Wang, Jian X., E-mail: jxwang@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Applied Science Laboratories, General Electric Healthcare (Canada); Wheatley, Andrew, E-mail: awheat@imaging.robarts.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); McCormack, David G., E-mail: David.Mccormack@lhsc.on.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Division of Respirology, Department of Medicine, The University of Western Ontario, London (Canada); Parraga, Grace, E-mail: gparraga@robats.ca [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Canada N6A 5K8 (Canada); Graduate Program in Biomedical Engineering, The University of Western Ontario, London (Canada); Department of Medical Imaging, The University of Western Ontario, London (Canada); Department of Medical Biophysics, The University of Western Ontario, London (Canada)

    2014-01-15

    Objective: The aim of this study was to quantitatively evaluate the relationship between short echo time pulmonary {sup 1}H magnetic resonance imaging (MRI) signal intensity (SI) and {sup 3}He MRI apparent diffusion coefficients (ADC), high-resolution computed tomography (CT) measurements of emphysema, and pulmonary function measurements. Materials and methods: Nine healthy never-smokers and 11 COPD subjects underwent same-day plethysmography, spirometry, short echo time ((TE) = 1.2 ms) {sup 1}H and diffusion-weighted hyperpolarized {sup 3}He MRI (b = 1.6 s/cm{sup 2}) at 3.0 T. In addition, for COPD subjects only, CT densitometry was also performed. Results: Mean {sup 1}H SI was significantly greater for never-smokers (12.1 ± 1.1 arbitrary units (AU)) compared to COPD subjects (10.9 ± 1.3 AU, p = 0.04). The {sup 1}H SI AP-gradient was also significantly greater for never-smokers (0.40 AU/cm, R{sup 2} = 0.94) compared to COPD subjects (0.29 AU/cm, R{sup 2} = 0.968, p = 0.05). There was a significant correlation between {sup 1}H SI and {sup 3}He ADC (r = −0.58, p = 0.008) and significant correlations between {sup 1}H MR SI and CT measurements of emphysema (RA{sub 950}, r = −0.69, p = 0.02 and HU{sub 15}, r = 0.66, p = 0.03). Conclusions: The significant and moderately strong relationship between {sup 1}H SI and {sup 3}He ADC, as well as between {sup 1}H SI and CT measurements of emphysema suggests that these imaging methods and measurements may be quantifying similar tissue changes in COPD and that pulmonary {sup 1}H SI may be used to monitor emphysema as a complement to CT and noble gas MRI.

  20. Quantitative 1H and hyperpolarized 3He magnetic resonance imaging: Comparison in chronic obstructive pulmonary disease and healthy never-smokers

    Objective: The aim of this study was to quantitatively evaluate the relationship between short echo time pulmonary 1H magnetic resonance imaging (MRI) signal intensity (SI) and 3He MRI apparent diffusion coefficients (ADC), high-resolution computed tomography (CT) measurements of emphysema, and pulmonary function measurements. Materials and methods: Nine healthy never-smokers and 11 COPD subjects underwent same-day plethysmography, spirometry, short echo time ((TE) = 1.2 ms) 1H and diffusion-weighted hyperpolarized 3He MRI (b = 1.6 s/cm2) at 3.0 T. In addition, for COPD subjects only, CT densitometry was also performed. Results: Mean 1H SI was significantly greater for never-smokers (12.1 ± 1.1 arbitrary units (AU)) compared to COPD subjects (10.9 ± 1.3 AU, p = 0.04). The 1H SI AP-gradient was also significantly greater for never-smokers (0.40 AU/cm, R2 = 0.94) compared to COPD subjects (0.29 AU/cm, R2 = 0.968, p = 0.05). There was a significant correlation between 1H SI and 3He ADC (r = −0.58, p = 0.008) and significant correlations between 1H MR SI and CT measurements of emphysema (RA950, r = −0.69, p = 0.02 and HU15, r = 0.66, p = 0.03). Conclusions: The significant and moderately strong relationship between 1H SI and 3He ADC, as well as between 1H SI and CT measurements of emphysema suggests that these imaging methods and measurements may be quantifying similar tissue changes in COPD and that pulmonary 1H SI may be used to monitor emphysema as a complement to CT and noble gas MRI

  1. 1H nuclear magnetic resonance spectroscopy-based metabonomic study in patients with cirrhosis and hepatic encephalopathy

    Dabos, Konstantinos John; Parkinson, John Andrew; Sadler, Ian Howard; Plevris, John Nicholas; Hayes, Peter Clive

    2015-01-01

    AIM: To identify plasma metabolites used as biomarkers in order to distinguish cirrhotics from controls and encephalopathics. METHODS: A clinical study involving stable cirrhotic patients with and without overt hepatic encephalopathy was designed. A control group of healthy volunteers was used. Plasma from those patients was analysed using 1H - nuclear magnetic resonance spectroscopy. We used the Carr Purcell Meiboom Gill sequence to process the sample spectra at ambient probe temperature. We used a gated secondary irradiation field for water signal suppression. Samples were calibrated and referenced using the sodium trimethyl silyl propionate peak at 0.00 ppm. For each sample 128 transients (FID’s) were acquired into 32 K complex data points over a spectral width of 6 KHz. 30 degree pulses were applied with an acquisition time of 4.0 s in order to achieve better resolution, followed by a recovery delay of 12 s, to allow for complete relaxation and recovery of the magnetisation. A metabolic profile was created for stable cirrhotic patients without signs of overt hepatic encephalopathy and encephalopathic patients as well as healthy controls. Stepwise discriminant analysis was then used and discriminant factors were created to differentiate between the three groups. RESULTS: Eighteen stabled cirrhotic patients, eighteen patients with overt hepatic encephalopathy and seventeen healthy volunteers were recruited. Patients with cirrhosis had significantly impaired ketone body metabolism, urea synthesis and gluconeogenesis. This was demonstrated by higher concentrations of acetoacetate (0.23 ± 0.02 vs 0.05 ± 0.00, P < 0.01), and b-hydroxybutarate (0.58 ± 0.14 vs 0.08 ± 0.00, P < 0.01), lower concentrations of glutamine (0.44 ± 0.08 vs 0.63 ± 0.03, P < 0.05), histidine (0.16 ± 0.01 vs 0.36 ± 0.04, P < 0.01) and arginine (0.08 ± 0.01 vs 0.14 ± 0.02, P < 0.03) and higher concentrations of glutamate (1.36 ± 0.25 vs 0.58 ± 0.04, P < 0.01), lactate (1.53 ± 0

  2. DIFFERENTIATION BETWEEN BENIGN PROSTATIC HYPERPLASIA AND PROSTATE CANCER IN THE TRANSITIONAL ZONE EVALUATED BY 1H MAGNETIC RESONANCE SPECTROSCOPIC IMAGING

    Sa-ying Li; Min Chen; Rui Wang; Cheng Zhou

    2007-01-01

    To quantitatively evaluate the metabolic changes of benign prostatic hyperplasia (BPH) and prostate cancer in the transitional zone using magnetic resonance spectroscopic imaging ( MRSI), and to analyze the characteristics and differences of the spectra in this zonal area.Methods Eighteen patients with prostate cancer in the transitional zone underwent magnetic resonance imaging( MRI)/MRSI examinations. The ( Choline + Creatine)/Citrate (CC/Ci) ratio and the Choline/Creatine (Cho/Cr) ratio were evaluated in each voxel with cancer or BPH confirmed by pathological results. Discriminant analysis was used to determine the power of the two ratios in differentiation between cancer and BPH.Results The CC/Ci ratio and Cho/Cr ratio for cancer voxels were significantly higher than those in the voxels with BPH in the transitional zone ( CC/Ci: 2.36 ± 1.31 vs. 0.85 ± 0.29, P < 0.01; Cho/Cr: 4.14 ± 1.79 vs. 1.26 ±0.45, P < 0.01 ). As for the discriminant function with the CC/Ci ratio and the Cho/Cr ratio, the specificity, sensitivity, and accuracy were 98.6%, 85.7%, 92.9% respectively for the differentiation between cancer and BPH.Conclusions The prostate cancer is characterized by higher CC/Ci ratio and Cho/Cr ratio compared to BPH in the transitional zone. Both CC/Ci ratio and Cho/Cr ratio have high specificity, sensitivity, and accuracy in their discriminative power between cancer and BPH in this zonal area.

  3. Whole-brain patterns of (1)H-magnetic resonance spectroscopy imaging in Alzheimer's disease and dementia with Lewy bodies.

    Su, L; Blamire, A M; Watson, R; He, J; Hayes, L; O'Brien, J T

    2016-01-01

    Magnetic resonance spectroscopy has demonstrated metabolite changes in neurodegenerative disorders such as Alzheimer's disease (AD) and dementia with Lewy bodies (DLB); however, their pattern and relationship to clinical symptoms is unclear. To determine whether the spatial patterns of brain-metabolite changes in AD and DLB are regional or diffused, and to examine whether the key metabolite levels are associated with cognitive and non-cognitive symptoms, we acquired whole-brain spatially resolved 3T magnetic resonance spectroscopic imaging (MRSI) data from subjects with AD (N=36), DLB (N=35) and similarly aged controls (N=35). Voxel-wise measurement of N-acetylaspartate to creatine (NAA/Cr), choline to Cr (Cho/Cr), myo-inositol to Cr (mI/Cr) as well as glutamate and glutamine to Cr (Glx/Cr) ratios were determined using MRSI. Compared with controls, AD and DLB groups showed a significant decrease in most brain metabolites, with NAA/Cr, Cho/Cr and mI/Cr levels being reduced in posterior cingulate, thalamus, frontotemporal areas and basal ganglia. The Glx/Cr level was more widely decreased in DLB (posterior cingulate, hippocampus, temporal regions and caudate) than in AD (only in posterior cingulate). DLB was also associated with increased levels of Cho/Cr, NAA/Cr and mI/Cr in occipital regions. Changes in metabolism in the brain were correlated with cognitive and non-cognitive symptoms in the DLB but not in the AD group. The different patterns between AD and DLB may have implications for improving diagnosis, better understanding disease-specific neurobiology and targeting therapeutics. In addition, the study raised important questions about the role of occipital neuroinflammation and glial activation as well as the glutamatergic treatment in DLB. PMID:27576166

  4. Chronic Cocaine Use and Its Association with Myocardial Steatosis Evaluated by 1H Magnetic Resonance Spectroscopy in African Americans

    Lai, Shenghan; Gerstenblith, Gary; Li, Ji; Zhu, Hong; Bluemke, David A.; Liu, Chia-Ying; Zimmerman, Stefan L.; Chen, Shaoguang; Lai, Hong; Treisman, Glenn

    2014-01-01

    Objectives Cardiac steatosis is a manifestation of ectopic fat deposition and is associated with obesity. The impact of chronic cocaine use on obesity measures and on the relationship between obesity measures and cardiac steatosis is not well-characterized. The objectives of this study were to compare obesity measures in chronic cocaine users and non-users, and to explore which factors, in addition to obesity measures, are associated with myocardial triglyceride in African Americans (AAs), using noninvasive magnetic resonance spectroscopy (MRS). Methods Between June 2004 and January 2014, 180 healthy AA adults without HIV infection, hypertension and diabetes were enrolled in an observational proton MRS and imaging study investigating factors associated with cardiac steatosis. Results Among these 180 participants, 80 were chronic cocaine users, and 100 were non-users. The median age (with IQR) was 42 (34-47) years. Obesity measures trended higher in cocaine users than non-users. The median myocardial triglyceride was 0.6% (IQR:0.4-1.1%). Among the factors investigated, years of cocaine use, leptin and visceral fat were independently associated with myocardial triglyceride. BMI and visceral fat, which were significantly associated with myocardial triglyceride in non-cocaine users, were not associated with myocardial triglycerides content in cocaine users. Conclusions This study shows (1) cocaine users may have more fat than nonusers and (2) myocardial triglyceride is independently associated with duration of cocaine use, leptin, and visceral fat in all subjects, while leptin and HDL-cholesterol, but not visceral fat or BMI, in cocaine users, suggesting that chronic cocaine use may modify the relationships between obesity measures and myocardial triglyceride. PMID:25325298

  5. Modeling sickle cell vasoocculsion in the rat leg: Quantification of trapped sickle cells and correlation with 31P metabolic and 1H magnetic resonance imaging changes

    The authors have developed an animal model to elucidate the acute effects of perfusion abnormalities on muscle metabolism induced by different density-defined classes of erythrocytes isolated from sickle cell anemia patients. Technetium-99m (99mTc)-labeled, saline-washed normal (AA), homozygous sickle (SS), or high-density SS (SS4) erythrocytes were injected into the femoral artery of the rat and quantitative 99mTc imaging, 31P magnetic resonance spectroscopy by surface coil at 2 teslas, and 1H magnetic resonance imaging at 0.15 tesla were performed. Between 5 and 25 μl of SS4 cells was trapped in the microcirculation of the thigh. In contrast, fewer SS discocytes (SS2) or AA cells were trapped. After injection of SS4 cells an initial increase in inorganic phosphate was observed in the region of the thigh served by the femoral artery, intracellular pH decreased, and subsequently the proton relaxation time T1 reached a broad maximum at 18-28 hr. When T1 obtained at this time was plotted against the volume of cells trapped, an increase of T1 over the control value of 411 ± 48 msec was found that was proportional to the number of cells trapped. They conclude that the densest SS cells are most effective at producing vasoocclusion. The extent of the change detected by 1H magnetic resonance imaging is dependent on the amount of cells trapped in the microcirculation and the magnitude of the initial increase of inorganic phosphate

  6. Analysis of metabolites in human brain tumors and cerebral infarctions using 31P- and 1H-magnetic resonance spectroscopy

    31P- and 1H-MRS with a 2.0 tesla MRI/S system was used to monitor the cerebral energy levels, phospholipid metabolism, intracellular pH, and lactate and amino acid levels in patients with brain tumors and cerebral infarctions. Studies of human brain tumors have suggested that the 31P-MRS of malignant brain tumors show low concentrations of phosphocreatine (PCr) and β-ATP, high levels of phosphomonoester (PME) and inorganic Pi, and an alkaline pH. The Pi, PME, and intracellular pH of malignant lymphoma were higher than those of other brain tumors. 1H-MRS showed an increase of lactate in malignant brain tumors and epidermoids. After ACNU administration, the tumor 31P-MRS showed transient reduction and elevation of Pi on five patients with malignant gliomas. Intracellular pH also showed a transient reduction during radiotherapy. 1H-MRS showed a reduction of lactate at the beginning of therapy and showed a marked re-elevation of lactate with tumor regrowth. After radiotherapy, the normal brain 31P-MRS showed transient elevation and reduction of Pi. Intracellular pH also showed a transient elevation during radiotherapy. To investigate the mechanism of hyperbaric oxygen therapy (HBO) in cerebral ischemia, changes of brain lactate level were estimated by 1H-MRS. Although the Lactate/Creatine ratio decreased consistently over time in all patients, it decreased more rapidly in the patients receiving HBO therapy than in those without such therapy. 1H-MRS demonstrated that HBO therapy may improve metabolism in the ischemic brain and reduces the lactate levels. 31P- and 1H-MRS are practical tools for the clinical analysis of cerebral disorders as well as for deciding on therapeutic procedures and evaluating the response. (K.H.)

  7. The Response of RIF-1 Fibrosarcomas to the Vascular-Disrupting Agent ZD6126 Assessed by In Vivo and Ex Vivo1H Magnetic Resonance Spectroscopy

    Basetti Madhu

    2006-07-01

    Full Text Available The response of radiation-induced fibrosarcoma1 (RIF-1 tumors treated with the vascular-disrupting agent (VDA ZD6126 was assessed by in vivo and ex vivo1H magnetic resonance spectroscopy (MRS methods. Tumors treated with 200 mg/kg ZD6126 showed a significant reduction in total choline (tCho in vivo 24 hours after treatment, whereas control tumors showed a significant increase in tCho. This response was investigated further within both ex vivo unprocessed tumor tissues and tumor tissue metabolite extracts. Ex vivo high-resolution magic angle spinning (HRMAS and 1H MRS of metabolite extracts revealed a significant reduction in phosphocholine and glycerophosphocholine in biopsies of ZD6126-treated tumors, confirming in vivo tCho response. ZD6126-induced reduction in choline compounds is consistent with a reduction in cell membrane turnover associated with necrosis and cell death following disruption of the tumor vasculature. In vivo tumor tissue water diffusion and lactate measurements showed no significant changes in response to ZD6126. Spin-spin relaxation times (T2 of water and metabolites also remained unchanged. Noninvasive 1H MRS measurement of tCho in vivo provides a potential biomarker of tumor response to VDAs in RIF-1 tumors.

  8. Artificial neural networks for classification in metabolomic studies of whole cells using 1H nuclear magnetic resonance.

    Brougham, D F

    2011-01-01

    We report the successful classification, by artificial neural networks (ANNs), of (1)H NMR spectroscopic data recorded on whole-cell culture samples of four different lung carcinoma cell lines, which display different drug resistance patterns. The robustness of the approach was demonstrated by its ability to classify the cell line correctly in 100% of cases, despite the demonstrated presence of operator-induced sources of variation, and irrespective of which spectra are used for training and for validation. The study demonstrates the potential of ANN for lung carcinoma classification in realistic situations.

  9. 1H-Nuclear Magnetic Resonance Analysis of the Triacylglyceride Composition of Cold-Pressed Oil from Camellia japonica

    Salinero, Carmen; Feás, Xesús; Mansilla, J. Pedro; Seijas, Julio A.; Vázquez-Tato, M. Pilar; Vela, Pilar; Sainz, María J.

    2012-01-01

    Camellia japonica (CJ) has oil-rich seeds, but the study of these oils has received little attention and has mainly focused only on their health properties. In the present work the relative composition of the fatty acid (FA) components of the triglycerides in cold-pressed oil from CJ is studied by 1H-NMR. The results obtained were: 75.75%, 6.0%, 0.17% and 18.67%, for oleic, linoleic, linolenic and saturated FA respectively. Levels of C18 unsaturated FA found in CJ oil were similar to those re...

  10. Detection and quantification of phenolic compounds in olive oil by high resolution 1H nuclear magnetic resonance spectroscopy

    High resolution 1H NMR spectroscopy has been employed as a versatile and rapid method to analyze the polar fraction of extra virgin olive oils containing various classes of phenolic compounds. The strategy for identification of phenolic compounds is based on the NMR chemical shifts of a large number of model compounds assigned by using two-dimensional (2D) NMR spectroscopy. Furthermore, 2D NMR was applied to phenolic extracts in an attempt to discover additional phenolic compounds. The 1H NMR methodology was successful in detecting simple phenols, such as p-coumaric acid, vanillic acid, homovanillyl alcohol, vanillin, free tyrosol, and free hydroxytyrosol, the flavonols apigenin and luteolin, the lignans (+) pinoresinol, (+) 1-acetoxypinoresinol and syringaresinol, two isomers of the aldehydic form of oleuropein and ligstroside, the dialdehydic form of oleuropein and ligstroside lacking a carboxymethyl group, and finally total hydroxytyrosol and total tyrosol reflecting the total amounts of free and esterified hydroxytyrol and tyrosol, respectively. The absolute amount of each phenolic constituent was determined in the polar fraction by using anhydrous 1,3,5-triazine as an internal standard

  11. Detection and quantification of phenolic compounds in olive oil by high resolution {sup 1}H nuclear magnetic resonance spectroscopy

    Christophoridou, Stella [NMR Laboratory, Department of Chemistry, University of Crete, P.O. Box 2208, Voutes, 71003 Heraklion, Crete (Greece); Dais, Photis [NMR Laboratory, Department of Chemistry, University of Crete, P.O. Box 2208, Voutes, 71003 Heraklion, Crete (Greece)], E-mail: dais@chemistry.uoc.gr

    2009-02-09

    High resolution {sup 1}H NMR spectroscopy has been employed as a versatile and rapid method to analyze the polar fraction of extra virgin olive oils containing various classes of phenolic compounds. The strategy for identification of phenolic compounds is based on the NMR chemical shifts of a large number of model compounds assigned by using two-dimensional (2D) NMR spectroscopy. Furthermore, 2D NMR was applied to phenolic extracts in an attempt to discover additional phenolic compounds. The {sup 1}H NMR methodology was successful in detecting simple phenols, such as p-coumaric acid, vanillic acid, homovanillyl alcohol, vanillin, free tyrosol, and free hydroxytyrosol, the flavonols apigenin and luteolin, the lignans (+) pinoresinol, (+) 1-acetoxypinoresinol and syringaresinol, two isomers of the aldehydic form of oleuropein and ligstroside, the dialdehydic form of oleuropein and ligstroside lacking a carboxymethyl group, and finally total hydroxytyrosol and total tyrosol reflecting the total amounts of free and esterified hydroxytyrol and tyrosol, respectively. The absolute amount of each phenolic constituent was determined in the polar fraction by using anhydrous 1,3,5-triazine as an internal standard.

  12. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time 1H magnetic resonance spectroscopy (MRS) study

    Raininko, Raili (Dept. of Radiology, Uppsala Univ., Uppsala (Sweden)), e-mail: raili.raininko@radiol.uu.se; Mattsson, Peter (Dept. of Neuroscience, Neurology, Uppsala Univ., Uppsala (Sweden))

    2010-04-15

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different 1H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people

  13. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time {sup 1}H magnetic resonance spectroscopy (MRS) study

    Raininko, Raili [Dept. of Radiology, Uppsala Univ., Uppsala (Sweden)], e-mail: raili.raininko@radiol.uu.se; Mattsson, Peter [Dept. of Neuroscience, Neurology, Uppsala Univ., Uppsala (Sweden)

    2010-04-15

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different {sup 1}H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people.

  14. Metabolite concentrations in supraventricular white matter from teenage to early old age: A short echo time 1H magnetic resonance spectroscopy (MRS) study

    Background: Age- and sex-related changes of metabolites in healthy adult brains have been examined with different 1H magnetic resonance spectroscopy (MRS) methods in varying populations, and with differing results. A long repetition time and short echo time technique reduces quantification errors due to T1 and T2 relaxation effects and makes it possible to measure metabolites with short T2 relaxation times. Purpose: To examine the effect of age on the metabolite concentrations measured by 1H MRS in normal supraventricular white matter using a long repetition time (TR) and a short echo time (TE). Material and Methods: Supraventricular white matter of 57 healthy subjects (25 women, 32 men), aged 13 to 72 years, was examined with a single-voxel MRS at 1.5T using a TR of 6000 ms and a TE of 22 ms. Tissue water was used as a reference in quantification. Results: Myoinositol increased slightly and total N-acetyl aspartate (NAA) decreased slightly with increasing age. Glutamine/glutamate complex (Glx) showed U-shaped age dependence, with highest concentrations in the youngest and oldest subjects. No significant age dependence was found in total choline and total creatine. No gender differences were found. Macromolecule/ lipid (ML) fractions were reliably measurable only in 36/57 or even fewer subjects and showed very large deviations. Conclusion: The concentrations of several metabolites in cerebral supraventricular white matter are age dependent on 1H MRS, even in young and middle-aged people, and age dependency can be nonlinear. Each 1H MRS study of the brain should therefore take age into account, whereas sex does not appear to be so important. The use of macromolecule and lipid evaluations is compromised by less successful quantification and large variations in healthy people

  15. Influence of fat and phytosterols concentration in margarines on their degradation at high temperature. A study by (1)H Nuclear Magnetic Resonance.

    Sopelana, P; Ibargoitia, María L; Guillén, María D

    2016-04-15

    The objective of this work was to study the influence of several factors, especially fat and phytosterols concentration, on the behavior of margarine under thermo-oxidative conditions. For this purpose, margarines with similar compositions in acyl groups, but differing in the concentration of both fat and phytosterols, were heated at 180°C. The changes in the main components of margarine lipids and the formation of new compounds throughout the thermal treatment were monitored by (1)H Nuclear Magnetic Resonance. The results show that the presence of high concentrations of phytosterols seems to have an antioxidant effect, since it slows down the thermo-oxidation rate of margarine and, consequently, the generation rate and concentrations of secondary oxidation products such as some aldehydes, epoxides and alcohols. The oil-water ratio also seems to have an important effect on margarine behavior, in such a way that the lower the fat concentration is, the higher its thermo-oxidation rate. PMID:26675865

  16. 1H nuclear magnetic resonance study of olive oils commercially available as Italian products in the United States of America.

    Del Coco, Laura; Schena, Francesco Paolo; Fanizzi, Francesco Paolo

    2012-05-01

    Multivariate analysis of (1)H NMR data has been used for the characterization of 12 blended olive oils commercially available in the U.S. as Italian products. Chemometric methods such as unsupervised Principal Component Analysis (PCA) allowed good discrimination and gave some affinity indications for the U.S. market olive oils compared to other single cultivars of extra virgin olive oil such as Coratina and Ogliarola from Apulia, one of Italy's leading olive oil producers, Picual (Spain), Kalamata (Greece) and Sfax (Tunisia). The olive oils commercially available as Italian products in the U.S. market clustered into 3 groups. Among them only the first (7 samples) and the second group (2 samples) showed PCA ranges similar to European references. Two oils of the third group (3 samples) were more similar to Tunisian references. In conclusion, our study revealed that most EVOO (extra virgin olive oils) tested were closer to Greek (in particular) and Spanish olive oils than Apulia EVOO. The PCA loadings disclose the components responsible for the discrimination as unsaturated (oleic, linoleic, linolenic) and saturated fatty acids. All are of great importance because of their nutritional value and differential effects on the oxidative stability of oils. It is evident that this approach has the potential to reveal the origin of EVOO, although the results support the need for a larger database, including EVOO from other Italian regions. PMID:22690321

  17. An Evaluation of 1-Deoxynojirimycin Oral Administration in Eri Silkworm through Fat Body Metabolomics Based on 1H Nuclear Magnetic Resonance

    Wen, Chao-wei; Lin, Xiao-dong; Dong, Min-jian; Deng, Ming-jie

    2016-01-01

    1-Deoxynojirimycin (DNJ), the main hypoglycemic constituent in mulberry (Morus alba) latex, has been extensively researched. Although there is considerable interest in the biological effects of DNJ, the roles of 1-deoxynojirimycin (DNJ) in glycometabolism and energy metabolism in insects have received little attention. In this paper, 1H nuclear magnetic resonance (1H NMR) based metabonomic was performed to study the effects of the oral supplementation of 0.25% DNJ, 0.5% DNJ, latex, and the mixture of 0.5% DNJ and latex (1 : 1) on the fat body glycometabolism and energy metabolism of the fourth-instar larvae of Eri silkworms, Samia cynthia ricini. Metabolic pattern recognition analysis (partial least square-discriminant analysis, PLS-DA) of fat body extracts indicated that the groups of 0.25% DNJ, 0.5% DNJ, latex, and the mixture of 0.5% DNJ and latex (1 : 1) were significantly different from the control group. Further, compared to the control group, the metabolites levels of lactate, trehalose, succinate, malate, and fumarate were remarkably changed in experimental groups, which were involved in glycolysis, hydrolysis of trehalose, and tricarboxylic acid (TCA) cycle. Our results indicate that DNJ has a positive impact on the reverse energy metabolism of Eri silkworms and metabonomic analysis based on NMR can be used as a tool to identify potential biomarkers. PMID:27294120

  18. Analysis of brain metabolism by proton magnetic resonance spectroscopy (1H-MRS) in attention-deficit/hyperactivity disorder suggests a generalized differential ontogenic pattern from controls.

    Arcos-Burgos, Mauricio; Londoño, Ana C; Pineda, David A; Lopera, Francisco; Palacio, Juan David; Arbelaez, Andres; Acosta, Maria T; Vélez, Jorge I; Castellanos, Francisco Xavier; Muenke, Maximilian

    2012-12-01

    Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder of childhood. Preliminary studies with proton magnetic resonance spectroscopy ((1)H-MRS) of the brain have reported differences in brain metabolite concentration-to-Cr ratios between individuals with ADHD and unaffected controls in several frontal brain regions including anterior cingulate cortex. Using multivoxel (1)H-MRS, we compared 14 individuals affected with ADHD to 20 individuals without ADHD from the same genetic isolate. After controlling by sex, age, and multiple testing, we found significant differences at the right posterior cingulate of the Glx/Cr ratio density distribution function between ADHD cases and controls (P metabolite concentration-to-Cr ratio, age, and ADHD status: Ins/Cr and Glx/Cr ratios at the left posterior cingulate, and NAA/Cr at the splenius, right posterior cingulate, and at the left posterior cingulate. We also found a differential metabolite ratio interaction between ADHD cases and controls for Ins/Cr and NAA/Cr at the right striatum. These results show that: (1) NAA/Cr, Glx/Cr, and Ins/Cr ratios, as reported in other studies, exhibit significant differences between ADHD cases and controls; (2) differences of these metabolite ratios between ADHD cases and controls evolve in specific and recognizable patterns throughout age, a finding that replicates previous results obtained by structural MRI, where is demonstrated that brain ontogeny follows a different program in ADHD cases and controls; (3) Ins/Cr and NAA/Cr ratios, at the right striatum, interact in a differential way between ADHD cases and controls. As a whole, these results replicate previous 1H-MRS findings and add new intriguing differential metabolic and ontogeny patterns between ADHD cases and controls that warrant further pursue. PMID:23012086

  19. Bevacizumab impairs oxidative energy metabolism and shows antitumoral effects in recurrent glioblastomas: a 31P/1H MRSI and quantitative magnetic resonance imaging study.

    Hattingen, Elke; Jurcoane, Alina; Bähr, Oliver; Rieger, Johannes; Magerkurth, Jörg; Anti, Sandra; Steinbach, Joachim P; Pilatus, Ulrich

    2011-12-01

    Bevacizumab shows unprecedented rates of response in recurrent glioblastomas (GBM), but the detailed mechanisms are still unclear. We employed in vivo magnetic resonance spectroscopic imaging (MRSI) and quantitative magnetic resonance imaging to investigate whether bevacizumab alters oxygen and energy metabolism and whether this effect has antitumoral activity in recurrent GBM. (31)P and (1)H MRSI, apparent diffusion coefficient (ADC), and high-resolution T2 and T2' mapping (indirect marker of oxygen extraction) were investigated in 16 patients with recurrent GBM at 3 Tesla before and 1.5-2 months after initiation of therapy with bevacizumab. Changes of metabolite concentrations and of the quantitative values in the tumor and normal appearing brain tissue were calculated. The Wilcoxon signed-ranks test was used to evaluate differences for tumor/edema versus control as well as changes before versus after commencement of therapy. Survival analyses were performed for significant parameters. Tumor T2', pH, ADC, and T2 decreased significantly in patients responding to bevacizumab therapy (n = 10). Patients with at least 25% T2' decrease during treatment showed longer progression-free and overall survival durations. Levels of high-energy metabolites were lower at baseline; these persisted under therapy. Glycerophosphoethanolamine as catabolic phospholipid metabolite increased in responders. The MRSI data support the hypothesis that bevacizumab induces relative tumor hypoxia (T2' decrease) and affects energy homeostasis in recurrent GBM, suggesting that bevacizumab impairs vascular function. The antiangiogenic effect of bevacizumab is predictive of better outcome and seems to induce antitumoral activity in the responding GBMs. PMID:21890539

  20. 1H and 31P nuclear magnetic resonance investigation of the interaction between 2,3-diphosphoglycerate and human normal adult hemoglobin

    High-resolution 1H and 31P nuclear magnetic resonance spectroscopy has been used to investigate the binding of 2,3-diphosphoglycerate to human normal adult hemoglobin and the molecular interactions involved in the allosteric effect of the 2,3-diphosphoglycerate molecule on hemoglobin. Individual hydrogen ion NMR titration curves have been obtained for 22-26 histidyl residues of hemoglobin and for each phosphate group of 2,3-diphosphoglycerate with hemoglobin in both the deoxy and carbonmonoxy forms. The results indicate that 2,3-diphosphoglycerate binds to deoxyhemoglobin at the central cavity between the two β chains and the binding involves the β2-histidyl residues. Moreover, the results suggest that the binding site of 2,3-diphosphoglycerate to carbonmonoxyhemoglobin contains the same (or at least some of the same) amino acid residues responsible for binding in the deoxy form. As a result of the specific interactions with 2,3-diphosphoglycerate, the β2-histidyl residues make a significant contribution to the alkaline Bohr effect under these experimental conditions. These results give the first experimental demonstration that long-range electrostatic and/or conformation effects of the binding could play an important role in the allosteric effect of 2,3-diphosphoglycerate on hemoglobin. The 31P nuclear magnetic resonance titration data for each phosphate group of 2,3-diphosphoglycerate have been used to calculate the pK values of the phosphate groups in 2,3-diphosphoglycerate bound to deoxy- and carbon-monoxyhemoglobin and the proton uptake by 2,3-diphosphoglycerate upon ligand binding to hemoglobin

  1. Analysis of Brain Metabolism by Proton-Magnetic-Resonance-Spectroscopy (1H-MRS) in Attention-Deficit/Hyperactivity Disorder Suggests a Generalized Differential Ontogenic Pattern from Controls

    Arcos-Burgos, Mauricio; Londoño, Ana C.; Pineda, David A.; Lopera, Francisco; Palacio, Juan David; Arbelaez, Andres; Acosta, Maria T.; Vélez, Jorge I.; Castellanos, Francisco Xavier; Muenke, Maximilian

    2012-01-01

    Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder of childhood. Preliminary studies with proton magnetic resonance spectroscopy (1HMRS) of the brain have reported differences in brain metabolite concentration-to-Cr ratios between individuals with ADHD and unaffected controls in several frontal brain regions including anterior cingulate cortex. Using multivoxel 1H-MRS, we compared 14 individuals affected with ADHD to 20 individuals without ADHD from the same genetic isolate. After controlling by sex, age and multiple testing, we found significant differences at the right posterior cingulate of the Glx/Cr ratio density distribution function between ADHD cases and controls (P<0.05). Furthermore, we found several interactions of metabolite concentration-to-Cr ratio, age, and ADHD status: Ins/Cr and Glx/Cr ratios at the left posterior cingulate, and NAA/Cr at the splenius, right posterior cingulate, and at the left posterior cingulate. We also found a differential metabolite ratio interaction between ADHD cases and controls for Ins/Cr and NAA/Cr at the right striatum. These results show that: 1) NAA/Cr, Glx/Cr and Ins/Cr ratios, as reported in other studies, exhibit significant differences between ADHD cases and controls; 2) differences of these metabolite ratios between ADHD cases and controls evolve in specific and recognizable patterns throughout age, a finding that replicates previous results obtained by structural MRI, where is demonstrated that brain ontogeny follows a different program in ADHD cases and controls; 3) Ins/Cr and NAA/Cr ratios, at the right striatum, interact in a differential way between ADHD cases and controls. As a whole, these results replicate previous 1H-MRS findings and add new intriguing differential metabolic and ontogeny patterns between ADHD cases and controls that warrant further pursue. PMID:23012086

  2. Dynamics of ferroelectric bis(imidazolium) pentachloroantimonate(III) by means of nuclear magnetic resonance 1H relaxometry and dielectric spectroscopy.

    Piecha-Bisiorek, A; Jakubas, R; Medycki, W; Florek-Wojciechowska, M; Wojciechowski, M; Kruk, D

    2014-05-22

    Some of haloantimonates(III) and halobismuthates(III) are ferroelectric. Bis(imidazolium) pentachloroantimonate(III), (C3N2H5)2SbCl5 (abbreviation: ICA) is the first example of such compounds with a one-dimensional anionic chain which exhibits ferroelectric properties. The relation between the ionic dynamics and network structure and the ferroelectric features is not clear. Here Nuclear Magnetic Resonance (NMR) (1)H spin-lattice relaxation experiments at 25 MHz are reported for ICA in the temperature range of 80 K-360 K, covering ferroelectric-paraelectric and structural phase transitions of the compound occurring at 180 and 342 K, respectively. The relaxation process is biexponential in the whole temperature range indicating two dynamically nonequivalent types of imidazolium cations. Temperature dependences of both relaxation contributions allow for identifying three motional processes. Two of them are cation-specific - i.e. they are attributed to the two types of imidazolium cations, respectively. The third process involves both types of cations, and it is characterized by much lower activation energy. Moreover, the relaxation data (combined with (1)H second moment measurements) show that the ferroelectric-paraelectric phase transition mechanism is governed, to a large extent, by the anionic network arrangement. The NMR studies are complemented by dielectric spectroscopy experiments performed in the vicinity of the Curie temperature, TC = 180 K, to get insight into the mechanism of the ferroelectric-paraelectric phase transition. The dielectric dispersion data show critical slowing down of the macroscopic relaxation time, τ, in ICA when approaching TC from the paraelectric side, indicating an order-disorder type of ferroelectrics. PMID:24804840

  3. Metabolic alterations produced by 3-nitropropionic acid in rat striata and cultured astrocytes: quantitative in vitro 1H nuclear magnetic resonance spectroscopy and biochemical characterization

    Quantitative high resolution in vitro 1H nuclear magnetic resonance spectroscopy was employed to study the metabolic effects of 3-nitropropionic acid associated with aging from perchloric acid extracts of rat striata. Systemic injection of 3-nitropropionic acid in rats at a dose of 10 mg/kg/day for seven consecutive days significantly impaired energy metabolism in rats one, four and eight months of age, as evidenced by a marked elevation of succinate and lactate levels. However, a significant decrease in N-acetyl-l-aspartate level, a neuronal marker, was observed in four- and eight-month-old rats but not in one-month-old rats. This would indicate that rats at four to eight months are more susceptible to 3-nitropropionic acid than those at one month. A significant decrease in GABA level was observed in four-month-old 3-nitropropionic acid-treated rats, which is consistent with the literature that GABAergic neurons are particularly vulnerable to 3-nitropropionic acid treatment. In addition, glutamine and glutamate levels were markedly decreased at four and eight months in 3-nitropropionic acid-treated rats. Since glutamine is synthesized predominantly in glia, the observation above suggests that 3-nitropropionic acid intoxication may involve perturbation of energy metabolism, glial injury and consequent neuronal damage. Astrocytes which are essential in the metabolism of glutamate and glutamine were used to further assess 3-nitropropionic acid-induced toxicity. Glial proliferation, mitochondrial metabolism and glutamine synthetase activity were all reduced by 3-nitropropionic acid treatment with a concomitant increase, in a dose-dependent manner, of lactate levels, suggesting that 3-nitropropionic acid is also detrimental to astrocytes in vivo and thus may affect metabolic interaction between neurons and glia.These results not only imply that 3-nitropropionic acid blocks energy metabolism prior to exerting neurotoxic damage but also demonstrate that the degree of

  4. Insula-specific 1H magnetic resonance spectroscopy reactions in heavy smokers under acute nicotine withdrawal and after oral nicotine substitution

    Gutzeit, Andreas; Froehlich, Johannes M; Hergan, Klaus; Graf, Nicole; Binkert, Christoph A; Meier, Dieter; Brügger, Mike; Reischauer, Carolin; Sutter, Reto; Herdener, Marcus; Schubert, Tillmann; Kos, Sebastian; Grosshans, Martin; Straka, Matus; Mutschler, Jochen

    2013-01-01

    The aim of this study was to clarify whether addiction-specific neurometabolic reaction patterns occur in the insular cortex during acute nicotine withdrawal in tobacco smokers in comparison to nonsmokers. Fourteen male smokers and 10 male nonsmokers were included. Neurometabolites of the right and the left insular cortices were quantified by magnetic resonance spectroscopy (MRS) on a 3-Tesla scanner. Three separate MRS measurements were performed in each subject: among the smokers, the first...

  5. Towards real-time metabolic profiling of a biopsy specimen during a surgical operation by 1H high resolution magic angle spinning nuclear magnetic resonance: a case report

    Piotto Martial

    2012-01-01

    Full Text Available Abstract Introduction Providing information on cancerous tissue samples during a surgical operation can help surgeons delineate the limits of a tumoral invasion more reliably. Here, we describe the use of metabolic profiling of a colon biopsy specimen by high resolution magic angle spinning nuclear magnetic resonance spectroscopy to evaluate tumoral invasion during a simulated surgical operation. Case presentation Biopsy specimens (n = 9 originating from the excised right colon of a 66-year-old Caucasian women with an adenocarcinoma were automatically analyzed using a previously built statistical model. Conclusions Metabolic profiling results were in full agreement with those of a histopathological analysis. The time-response of the technique is sufficiently fast for it to be used effectively during a real operation (17 min/sample. Metabolic profiling has the potential to become a method to rapidly characterize cancerous biopsies in the operation theater.

  6. Possibilities and limitations of sup 1 H and sup 13 C nuclear magnetic resonance spectroscopy for the identification and the quantitative determination of some naturally occurring carcinogenic risk factors. [Senecio vulgaris; Senecio vernalis; Senecio jacobaea; Euphorbia ingens

    Pieters, L.

    1988-01-01

    The aim of this work was to develop a phytochemical screening method for some selected carcinogenic or tumor-promoting principles in higher plants. The pyrrolizidine alkaloids from some Senecio species (Compositae or Asteraceae), and the diterpene ester from Croton tiglium L. and Euphorbia ingens E. Mey (Euphorbiaceae) were chosen as representatives of both groups. The possibilities and limitations of {sup 1}H and {sup 13}C nuclear magnetic resonance spectroscopy ({sup 1}H and {sup 13}C NMR) for the analysis of mixtures of carcinogenic pyrrolizidine alkaloids were compared with high performance liquid chromatography, and gas chromatography with high performance liquid chromatography, and gas chromatography was well as gas chromatography - mass spectrometry. Senecio vulgaris L., Senecio vernalis Waldst. and Kit. and Senecio jacobaea L. were investigated.

  7. Tumor Metabolism and Perfusion in Head and Neck Squamous Cell Carcinoma: Pretreatment Multimodality Imaging With 1H Magnetic Resonance Spectroscopy, Dynamic Contrast-Enhanced MRI, and [18F]FDG-PET

    Purpose: To correlate proton magnetic resonance spectroscopy (1H-MRS), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and 18F-labeled fluorodeoxyglucose positron emission tomography ([18F]FDG PET) of nodal metastases in patients with head and neck squamous cell carcinoma (HNSCC) for assessment of tumor biology. Additionally, pretreatment multimodality imaging was evaluated for its efficacy in predicting short-term response to treatment. Methods and Materials: Metastatic neck nodes were imaged with 1H-MRS, DCE-MRI, and [18F]FDG PET in 16 patients with newly diagnosed HNSCC, before treatment. Short-term patient radiological response was evaluated at 3 to 4 months. Correlations among 1H-MRS (choline concentration relative to water [Cho/W]), DCE-MRI (volume transfer constant [Ktrans]; volume fraction of the extravascular extracellular space [ve]; and redistribution rate constant [kep]), and [18F]FDG PET (standard uptake value [SUV] and total lesion glycolysis [TLG]) were calculated using nonparametric Spearman rank correlation. To predict short-term responses, logistic regression analysis was performed. Results: A significant positive correlation was found between Cho/W and TLG (ρ = 0.599; p = 0.031). Cho/W correlated negatively with heterogeneity measures of standard deviation std(ve) (ρ = −0.691; p = 0.004) and std(kep) (ρ = −0.704; p = 0.003). Maximum SUV (SUVmax) values correlated strongly with MRI tumor volume (ρ = 0.643; p = 0.007). Logistic regression indicated that std(Ktrans) and SUVmean were significant predictors of short-term response (p 1H-MRS, DCE-MRI, and [18F]FDG PET is feasible in HNSCC patients with nodal metastases. Additionally, combined DCE-MRI and [18F]FDG PET parameters were predictive of short-term response to treatment.

  8. Quantitative nuclear magnetic resonance spectrometry II. Purity of phosphorus-based agrochemicals glyphosate (N-(phosphonomethyl)-glycine) and profenofos (O-(4-bromo-2-chlorophenyl) O-ethyl S-propyl phosphorothioate) measured by 1H and 31P QNMR spectrometry

    The purities of the widely-used herbicide glyphosate (N-(phosphonomethyl)glycine), and the insecticide profenofos (O-(4-bromo-2-chlorophenyl) O-ethyl S-propyl phosphorothioate) were determined by 1H and 31P quantitative nuclear magnetic resonance (QNMR) spectrometry using an internal standard. QNMR does not need a standard reference of the same target analyte, in contrast to chromatographic methods, but only a compound containing the nucleus of interest. Sodium acetate and sodium phosphate of known purity were chosen as internal standards for 1H NMR and 31P NMR), respectively for the water soluble glyphosate and a single internal standard, trimethyl phosphate for both 1H and 31P NMR quantitative analysis of the organic soluble profenofos. These standards have NMR peaks that do not interfere with those of the analyte, they are chemically inert and are soluble in the deuterated solvent. The average purity of glyphosate obtained by 1H NMR (97.07%, σ=0.68) agreed with that by 31P NMR (96.53%, σ=0.90; ANOVA, P=0.074) for the five batches provided by the manufacturer according to the procedures for chemical registration in Australia. The standard deviations of seven independent analyses of a single batch by 1H NMR and 31P NMR were σ=0.24% and σ=0.33%, respectively, values which confirm the exceptional precision of the method. The purity of profenofos by 1H NMR (94.63%, σ=0.14) also agreed with that by 31P NMR (94.62%, σ=0.59; ANOVA, P=0.97). Uncertainty budgets for the measured purities of glyphosate and profenofos show that the uncertainty in the purity of the internal standard is a major contributor to the uncertainty of the result. NMR was also used to establish the impurity profile of both compounds, and quantify the impurities present

  9. Analysis of metabolites in human brain tumors and cerebral infarctions using {sup 31}P- and {sup 1}H-magnetic resonance spectroscopy

    Hirakawa, Wataru [Kagoshima Univ. (Japan). Faculty of Medicine

    1996-08-01

    {sup 31}P- and {sup 1}H-MRS with a 2.0 tesla MRI/S system was used to monitor the cerebral energy levels, phospholipid metabolism, intracellular pH, and lactate and amino acid levels in patients with brain tumors and cerebral infarctions. Studies of human brain tumors have suggested that the {sup 31}P-MRS of malignant brain tumors show low concentrations of phosphocreatine (PCr) and {beta}-ATP, high levels of phosphomonoester (PME) and inorganic Pi, and an alkaline pH. The Pi, PME, and intracellular pH of malignant lymphoma were higher than those of other brain tumors. {sup 1}H-MRS showed an increase of lactate in malignant brain tumors and epidermoids. After ACNU administration, the tumor {sup 31}P-MRS showed transient reduction and elevation of Pi on five patients with malignant gliomas. Intracellular pH also showed a transient reduction during radiotherapy. {sup 1}H-MRS showed a reduction of lactate at the beginning of therapy and showed a marked re-elevation of lactate with tumor regrowth. After radiotherapy, the normal brain {sup 31}P-MRS showed transient elevation and reduction of Pi. Intracellular pH also showed a transient elevation during radiotherapy. To investigate the mechanism of hyperbaric oxygen therapy (HBO) in cerebral ischemia, changes of brain lactate level were estimated by {sup 1}H-MRS. Although the Lactate/Creatine ratio decreased consistently over time in all patients, it decreased more rapidly in the patients receiving HBO therapy than in those without such therapy. {sup 1}H-MRS demonstrated that HBO therapy may improve metabolism in the ischemic brain and reduces the lactate levels. {sup 31}P- and {sup 1}H-MRS are practical tools for the clinical analysis of cerebral disorders as well as for deciding on therapeutic procedures and evaluating the response. (K.H.)

  10. Effects of time and temperature of firing on Fe-rich ceramics studied by Mössbauer spectroscopy and two-dimensional 1H-nuclear magnetic resonance relaxometry

    Casieri, Cinzia; De Luca, Francesco; Nodari, Luca; Russo, Umberto; Terenzi, Camilla; Tudisca, Valentina

    2012-10-01

    The combined effects of firing temperature and soaking time on the microstructure of iron-rich porous ceramics have been studied by 57Fe-Mössbauer spectroscopy and 2D 1H nuclear magnetic resonance (NMR) relaxometry using a single-sided probe. Examining water-saturated ceramics using the relaxation correlation method, where longitudinal (T1) and transverse (T2) relaxation times are measured concurrently, provides information about firing-induced changes in both porosity (related to T1) and magnetic properties (related to T2). Comparing the information obtained from 1H-NMR analyses with that obtained from Mössbauer spectroscopy (which characterizes changes in iron-bearing species) shows that the T1-T2 NMR correlation technique is very sensitive to even subtle modifications in the magnetic behavior of Fe-bearing species. Moreover, the single-sided NMR approach allows us to perform millimeter-scale depth-resolved measurements, which can be used to non-invasively study the microstructural heterogeneities associated with non-uniform firing effects inside ceramics. This is in contrast to Mössbauer spectroscopy, which requires that the ceramic samples be ground.

  11. 1H-Magnetic resonance spectroscopy study of stimulant medication effect on brain metabolites in French Canadian children with attention deficit hyperactivity disorder

    BenAmor L

    2014-01-01

    Full Text Available Leila BenAmor1,21Department of Psychiatry Sainte-Justine Hospital, Montreal, Quebec, Canada; 2Department of Psychiatry, University of Montreal, Montreal, Quebec, CanadaBackground: Attention deficit hyperactivity disorder (ADHD is a common neurodevelopmental disorder in school aged children. Functional abnormalities have been reported in brain imaging studies in ADHD populations. Psychostimulants are considered as the first line treatment for ADHD. However, little is known of the effect of stimulants on brain metabolites in ADHD patients.Objectives: To compare the brain metabolite concentrations in children with ADHD and on stimulants with those of drug naïve children with ADHD, versus typically developed children, in a homogenous genetic sample of French Canadians.Methods: Children with ADHD on stimulants (n=57 and drug naïve children with ADHD (n=45 were recruited, as well as typically developed children (n=38. The presence or absence of ADHD diagnosis (Diagnostic and Statistical Manual of Mental Disorders IV criteria was based on clinical evaluation and The Diagnostic Interview Schedule for Children IV. All children (n=140 underwent a proton magnetic resonance spectroscopy session to measure the ratio of N-acetyl-aspartate, choline, glutamate, and glutamate–glutamine to creatine, respectively, in the left and right prefrontal and striatal regions of the brain, as well as in the left cerebellum.Results: When compared with drug naïve children with ADHD, children with ADHD on stimulants and children typically developed were found to have higher choline ratios in the left prefrontal region (P=0.04 and lower N-acetyl-aspartate ratios in the left striatum region (P=0.01, as well as lower glutamate–glutamine ratios in the left cerebellum (P=0.05. In these three regions, there was no difference between children with ADHD on stimulants and typically developed children.Conclusion: Therapeutic psychostimulant effects in children with ADHD may be

  12. Multivariate analysis of fingerprinting of majority secondary metabolites of propolis of Costa Rica using proton nuclear magnetic resonance (1H-NMR)

    Propolis is produced by Apis mellifera bees from resins of plants that are found around the apiary. The chemical composition is highly variable and Costa Rica has reported without studies of characterization to define the types of propolis in the country. 119 samples were collected from beekeeping areas of the country. The spectrum of 1H-NMR and its antioxidant activity against DPPH radical were measured. The spectra have been divided into 243 blocks of 0,04 ppm and processed with the Minitab software for multivariate analysis. 99 of the samples collected were used for construction of models for the valuation of the predictive ability of the model have been used coefficients of determination (R2) of prediction by the software and the remaining 20 samples. The existence of three types of propolis with chemically different metabolomes were determined by principal component analysis (PCA). A prediction model was constructed by analysis of partial least squares (PLS). The prediction model has allowed to classify a propolis according to the level of anti-oxidant activity (AAO), high (type I and II) or low (type III) from the spectrum of 1H-NMR. The R2 has been 0.88 and R2 prediction of 0, 718 for new samples. The n-coniferyl benzoate of group I and nemorosone of the group II as two discriminated antioxidants among the groups I and II were isolated and high concentration levels of these compounds have been differentiated with respect to type III. This has allowed the construction of a linear discriminant model with a success rate of 100% for the samples used for formulation and 92,9 for the prediction of different samples. The classification systems could be applied to the standardization of the quality of propolis from Costa Rica for future medicinal or cosmetic applications that take advantage of its antioxidant properties. Also, the methylated derivative has isolated and identified of the n-coniferyl benzoate thereof propolis than was obtained his counterpart

  13. Thalamus in Patients with Obsessive-Compulsive Disorder:1H Magnetic Resonance Spectroscopy Study%丘脑1H磁共振波谱成像在强迫症中的应用

    尤超; 谭令; 范青; 丁蓓; 肖泽萍; 陈克敏

    2011-01-01

    目的 基于强迫症前额叶-纹状体-丘脑环路障碍假说,采用磁共振波谱成像(1H-MRS)研究成人强迫症(OCD)患者双侧丘脑1H-MRS表现及其与临床症状的关系.方法 13例经临床确诊的强迫症患者和与之相匹配的14例健康志愿者,分别行11.5TMRI的MRS检查,采用单体素点回波成像序列,采集双侧丘脑的波谱图像.所获图像经Sage软件后处理相应代谢指标N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、肌醇(Mi),测量NAA/Cr,Cho/Cr,Mi/Cr峰高相对值;并分析上述各值与OCD患者临床评分及病程时间的相关性.结果 与健康对照相比,OCD患者双侧丘脑的Mi/Cr、NAA/Cr明显降低,具有显著统计学差异;并且右侧丘脑NAA/Cr与强迫症病程时间呈负相关(r=-0.963,P<0.001).结论 OCD患者双侧丘脑NAA及Mi代谢物含量降低,1H-MRS可反映OCD患者丘脑代谢物的变化特征,并且可以证实OCD前额叶-纹状体-丘脑环路障碍的假说.%Objective On the basis of the hypothesis that patients with obsessive-compulsive disorder( OCD) have dysfunction of fronto-striato-thalamocortical circuitry, to study the metabolism change in the bilateral thalamic region with 1H magnetic resonance spectroscopy ( 1 H- MRS) and its correlations with clinical scale. Methods 13 patients with OCD and 14 matched healthy volunteers were enrolled in this study. Single voxel proton magnetic resonance spectroscopy was used to examine the bilateral thalamus for each subject. N-acetylaspartate(NAA), creatine(Cr), choline( Cho) and myo-inositol( mI) value of bilateral thalamus were acquired by using Sage software. Then the relativity of the MRS results and clinical scale were analyzed. Results A significant reduction in NAA/Cr and mI/Cr were observed in bilateral thalamus, and NAA/Cr of right thalamu was negative correlated with the course of OCD(r= -0. 963,P<0. 001). Conclusion Neuronal loss and NAA and ml decreased can be detected by using proton MRS in OCD

  14. MRI (Magnetic Resonance Imaging)

    ... Procedures Medical Imaging MRI (Magnetic Resonance Imaging) MRI (Magnetic Resonance Imaging) Share Tweet Linkedin Pin it More sharing options ... 8 MB) Also available in Other Language versions . Magnetic Resonance Imaging (MRI) is a medical imaging procedure for making ...

  15. Magnetic resonance angiography

    MRA; Angiography - magnetic resonance ... Kwong RY. Cardiovascular Magnetic Resonance Imaging. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine . ...

  16. 1H relaxation enhancement induced by nanoparticles in solutions: Influence of magnetic properties and diffusion

    Magnetic nanoparticles that induce nuclear relaxation are the most promising materials to enhance the sensitivity in Magnetic Resonance Imaging. In order to provide a comprehensive understanding of the magnetic field dependence of the relaxation enhancement in solutions, Nuclear Magnetic Resonance 1H spin-lattice relaxation for decalin and toluene solutions of various Fe2O3 nanoparticles was investigated. The relaxation experiments were performed in a frequency range of 10 kHz–20 MHz by applying Field Cycling method, and in the temperature range of 257–298 K, using nanoparticles differing in size and shape: spherical – 5 nm diameter, cubic – 6.5 nm diameter, and cubic – 9 nm diameter. The relaxation dispersion data were interpreted in terms of a theory of nuclear relaxation induced by magnetic crystals in solution. The approach was tested with respect to its applicability depending on the magnetic characteristics of the nanocrystals and the time-scale of translational diffusion of the solvent. The role of Curie relaxation and the contributions to the overall 1H spin-lattice relaxation associated with the electronic spin-lattice and spin-spin relaxation was thoroughly discussed. It was demonstrated that the approach leads to consistent results providing information on the magnetic (electronic) properties of the nanocrystals, i.e., effective electron spin and relaxation times. In addition, features of the 1H spin-lattice relaxation resulting from the electronic properties of the crystals and the solvent diffusion were explained

  17. Fat fraction value measured by proton magnetic resonance spectroscopy in osteoporosis:a Meta analysis%骨质疏松症1H-MRS脂肪分数定量研究:Meta分析

    张慈慈; 沈思; 汪飞; 邱麟; 刘斯润

    2015-01-01

    Objective To have a systemic review of the association between fat fraction value measured by proton magnetic resonance spectroscopy and osteoporosis bone mineral density, and to explore if fat fraction can be a reliable indicator for the diagnosis osteoporosis like bone mineral density. Methods Pubmed, Cochrane library, Medline, and China National Knowledge Infrastructure (CNKI) datebases (from January, 2000 to December, 2014) were searched to collect articles about proton magnetic resonance spectroscopy assessing osteoporosis. The data of fat fraction in osteoporosis group and normal group and Pearson correlation coefficient between bone mineral density and fat fraction were extracted from the articles. Pooled weighted mean difference (WMD) and 95%confidence interval, Pearson correlation coefficient between bone mineral density and fat fraction were done using review manager 5. 0 software. Results Nine articles (seven English articles, two Chinese articles) were included with 499 cases (210 normal and 289 osteoporosis). The fat fraction value was higher in osteoporosis than normal (WMD 9.25, 95%CI:6.95 to 11.56). A negative correlation was found between fat fraction value and bone mineral density (-0.59,95%CI:-0.76~-0.42). Conclusion Fat fraction measured by Proton magnetic resonance spectroscopy has certain clinical value in the assessment of osteoporosis, it can be used as a supplemental examination of DXA. Whether it can be a reliable indicator for the diagnosis osteoporosis like bone mineral density, the feasibility and accuracy need more research.%目的:采用Meta 分析的方法综合评价1H-MRS 相对定量指标脂肪分数与骨质疏松症骨密度的关系,探索脂肪分数能否如骨密度一样成为诊断骨质疏松症的可靠指标。方法检索 Pubmed、Cochrane 图书馆、Medline、中国知网(CNKI)等数据库中2000年1月—2014年12月公开发表的有关1H-MRS评价骨质疏松的中英文文献,提取文献中骨质疏

  18. Two-dimensional 1H nuclear magnetic resonance study of AaH IT, an anti-insect toxin from the scorpion Androctonus australis Hector. Sequential resonance assignments and folding of the polypeptide chain

    Sequence-specific nuclear magnetic resonance assignments for the polypeptide backbone and for most of the amino acid side-chain protons, as well as the general folding of AaH IT, are described. AaH IT is a neurotoxin purified from the venom of the scorpion Androctonus australis Hector and is specifically active on the insect nervous system. The secondary structure and the hydrogen-bonding patterns in the regular secondary structure elements are deduced from nuclear Overhauser effects and the sequence locations of the slowly exchanging amide protons. The backbone folding is determined by distance geometry calculations with the DISMAN program. The regular secondary structure includes two and a half turns of α-helix running from residues 21 to 30 and a three-stranded antiparallel β-sheet including peptides 3-5, 34-38, and 41-46. Two tight turns are present, one connecting the end of the α-helix to an external strand of the β-sheet, i.e., turn 31-34, and another connecting this same strand to the central one, i.e., turn 38-41. The differences in the specificity of these related proteins, which are able to discriminate between mammalian and insect voltage-dependent sodium channels of excitable tissues, are most probably brought about by the position of the C-terminal peptide with regard to a hydrophobic surface common to all scorpion toxins examined thus far. Thus, the interaction of a given scorpion toxin with its receptor might well be governed by the presence of this solvent-exposed hydrophobic surface, whereas adjacent areas modulate the specificity of the interaction

  19. The study of 1H-Magnetic resonance spectroscope (1H-MRS) in the anterior cingulate cortex (ACC) in depressive patients with childhood neglect%伴儿童期忽略的抑郁症患者前扣带回氢质子波谱对照研究

    彭红军; 李凌江; 贺忠

    2013-01-01

    目的 探讨伴儿童期忽略抑郁症患者前扣带回氢质子波谱物质代谢的特点.方法 采用儿童期创伤问卷(childhood trauma questionnaire,CTQ)对40例抑郁症患者进行儿童期忽略评估和分组,伴儿童期忽略抑郁症组19例患者和不伴儿童期忽略抑郁症组21例患者,以及20名正常对照行磁共振氢质子波谱(hydrogen magnetic resonance spectroscopy,1H-MRS)扫描,兴趣区选取双侧前扣带回(anterior cingulate cortex,ACC),检测N-乙酰天门冬氨酸(N-acetyl aspartate,NAA)、谷氨酸复合物(glutamate/glutamine,Glx)、胆碱(choline,Cho)、肌醇(myo-inositol,mI)及肌酸(creatine,Cr)水平,比较3组NAA/Cr、Glx/Cr、Cho/Cr和mI/Cr比值的差异.结果 伴与不伴儿童期忽略抑郁症组分别与对照组比较,左右两侧ACC均表现NAA/Cr降低(均P<0.010);2组右侧Glx/Cr均低于对照组(均P<0.001);伴儿童期忽略抑郁症组较不伴儿童期忽略抑郁症组左右两侧NAA/Cr差异均有统计学意义(左P<0.005,右P<0.01).结论 抑郁症患者前扣带回物质代谢不同于正常人;伴儿童期忽略抑郁症患者ACC的物质代谢存在特异性改变.

  20. Magnetic Resonance Imaging (MRI)

    ... How Can I Help a Friend Who Cuts? Magnetic Resonance Imaging (MRI) KidsHealth > For Teens > Magnetic Resonance Imaging (MRI) Print A A A Text Size What's ... Exam Safety Getting Your Results What Is MRI? Magnetic resonance imaging (MRI) is a type of safe, painless testing ...

  1. Recommendations concerning magnetic resonance spectroscopy

    In medicine the technique of nuclear magnetic resonance (NMR) is applied in the form of in vivo nuclear magnetic resonance spectroscopy (MRS). In vivo MRS can be carried out non-invasively. The committee of the Dutch Health Council briefly discusses the qualities and potentialities of the nuclei that will probably be used in future clinical spectroscopy: 31P, 13C, 1H (and possibly 19F and 23Na). The committee discusses several possibilities of combining imaging and spectroscopy. The imaging of nuclei other than protons is also possible with MRS. Potential applications are considered in oncology, cardiology, neurology and hepatology. (Auth.)

  2. {sup 1}H relaxation enhancement induced by nanoparticles in solutions: Influence of magnetic properties and diffusion

    Kruk, D., E-mail: danuta.kruk@matman.uwm.edu.pl [Faculty of Mathematics and Computer Science, University of Warmia and Mazury in Olsztyn, Słoneczna 54, 10-710 Olsztyn (Poland); Experimentalphysik II, Universität Bayreuth, 95440 Bayreuth (Germany); Korpała, A. [Department of Biophysics, Jagiellonian University Medical College, Łazarza 16, 31-530 Kraków (Poland); Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków (Poland); Taheri, S. Mehdizadeh; Förster, S. [Department of Physical Chemistry I, Universität Bayreuth, 95440 Bayreuth (Germany); Kozłowski, A. [NU-MED Group Inc., Center of Radiotherapy and Improvements in Elbląg, Królewiecka 146, 82-300 Elbląg (Poland); Rössler, E. A. [Experimentalphysik II, Universität Bayreuth, 95440 Bayreuth (Germany)

    2014-05-07

    Magnetic nanoparticles that induce nuclear relaxation are the most promising materials to enhance the sensitivity in Magnetic Resonance Imaging. In order to provide a comprehensive understanding of the magnetic field dependence of the relaxation enhancement in solutions, Nuclear Magnetic Resonance {sup 1}H spin-lattice relaxation for decalin and toluene solutions of various Fe{sub 2}O{sub 3} nanoparticles was investigated. The relaxation experiments were performed in a frequency range of 10 kHz–20 MHz by applying Field Cycling method, and in the temperature range of 257–298 K, using nanoparticles differing in size and shape: spherical – 5 nm diameter, cubic – 6.5 nm diameter, and cubic – 9 nm diameter. The relaxation dispersion data were interpreted in terms of a theory of nuclear relaxation induced by magnetic crystals in solution. The approach was tested with respect to its applicability depending on the magnetic characteristics of the nanocrystals and the time-scale of translational diffusion of the solvent. The role of Curie relaxation and the contributions to the overall {sup 1}H spin-lattice relaxation associated with the electronic spin-lattice and spin-spin relaxation was thoroughly discussed. It was demonstrated that the approach leads to consistent results providing information on the magnetic (electronic) properties of the nanocrystals, i.e., effective electron spin and relaxation times. In addition, features of the {sup 1}H spin-lattice relaxation resulting from the electronic properties of the crystals and the solvent diffusion were explained.

  3. Magnetic Resonance Imaging (MRI)

    ... Resonance Imaging (MRI) What is an MRI? MRI stands for Magnetic Resonance Imaging. It is an important ... MRI is often used for diagnosis or for monitoring disease. For example, if someone is having severe ...

  4. Assignment of the side-chain 1H and 13C resonances of interleukin-1β using double- and triple-resonance heteronuclear three-dimensional NMR spectroscopy

    The assignment of the aliphatic 1H and 13C resonances of IL-1β, a protein of 153 residues and molecular mass 17.4 kDa, is presented by use of a number of novel three-dimensional (3D) heteronuclear NMR experiments which rely on large heteronuclear one-bond J couplings to transfer magnetization and establish through-bond connectivities. These 3D NMR experiments circumvent problems traditionally associated with the application of conventional 2D 1H-1H correlation experiments to proteins of this size, in particular the extensive chemical shift overlap which precludes the interpretation of the spectra and the reduced sensitivity arising from 1H line widths that are often significantly larger than the 1H-1H J couplings. The assignment proceeds in two stages. In the first step the 13Cα chemical shifts are correlated with the NH and 15N chemical shifts by a 3D triple-resonance NH-15N-13Cα (HNCA) correlation experiment which reveals both intraresidue NH(i)-15N(i)-13Cα(i) and some weaker interresidue NH(i)-15N(i)-Cα(i-1) correlations, the former via intraresidue one-bond 1JNCα and the latter via interresidue two-bond 2HNCα couplings. The second step involves the identification of side-chain spin systems by 3D 1H-13C-13C-1H correlated (HCCH-COSY) and 3D 1H-13C-13C-1H total correlated (HCCH-TOCSY) spectroscopy, the latter making use of isotropic mixing of 13C magnetization to obtain relayed connectivities along the side chains. The authors were able to obtain complete 1H and 13C side-chain assignments for all residues, with the exception of 4 (out of a total of 15) lysine residues for which partial assignments were obtained

  5. Detection of kestoses and kestose-related oligosaccharides in extracts of Festuca arundinacea, Dactylis glomerate L. , and Asparagus officinalis L. root cultures and invertase by sup 13 C and sup 1 H nuclear magnetic resonance spectroscopy

    Forsythe, K.L.; Feather, M.S.; Gracz, H.; Wong, T.C. (Univ. of Missouri, Columbia (USA))

    1990-04-01

    Previous studies show that {sup 13}C nuclear magnetic resonance spectroscopy can be used to detect and identify mixtures of 1-kestose and neokestose after conversion to the acetate derivatives. In this study, unequivocal assignments are made for the anomeric carbon and proton signals for the above two trisaccharide acetates as well as for 6-kestose hendecaacetate and for nystose tetradecaacetate (a 1-kestose-derived tetrasaccharide). A number of oligosaccharide fractions were isolated from several plant species, converted to the acetates, and nuclear magnetic resonance spectra obtained. Using the above reference data, the following information was obtained. The trisaccharide fraction from Dactylis gomerata L. stem tissue and Asparagus officinalis L. roots contain both 1-kestose and neokestose, and the tetrasaccharide fractions contain three components, one of which is nystose. Penta- and hexasaccharide acetates were also isolated from A. officinalis L. roots and were found to contain, respectively, four and at least five components. All components of both of the above species appear to contain a kestose residue and to be produced by the sequential addition of fructofuranosyl units to these. The trisaccharide fraction from Festuca arundinacea is complex, and contains at least five different components, two of which appear to be 1-kestose and neokestose.

  6. Selective excitation enables assignment of proton resonances and {sup 1}H-{sup 1}H distance measurement in ultrafast magic angle spinning solid state NMR spectroscopy

    Zhang, Rongchun; Ramamoorthy, Ayyalusamy, E-mail: ramamoor@umich.edu [Biophysics and Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055 (United States)

    2015-07-21

    Remarkable developments in ultrafast magic angle spinning (MAS) solid-state NMR spectroscopy enabled proton-based high-resolution multidimensional experiments on solids. To fully utilize the benefits rendered by proton-based ultrafast MAS experiments, assignment of {sup 1}H resonances becomes absolutely necessary. Herein, we propose an approach to identify different proton peaks by using dipolar-coupled heteronuclei such as {sup 13}C or {sup 15}N. In this method, after the initial preparation of proton magnetization and cross-polarization to {sup 13}C nuclei, transverse magnetization of desired {sup 13}C nuclei is selectively prepared by using DANTE (Delays Alternating with Nutations for Tailored Excitation) sequence and then, it is transferred to bonded protons with a short-contact-time cross polarization. Our experimental results demonstrate that protons bonded to specific {sup 13}C atoms can be identified and overlapping proton peaks can also be assigned. In contrast to the regular 2D HETCOR experiment, only a few 1D experiments are required for the complete assignment of peaks in the proton spectrum. Furthermore, the finite-pulse radio frequency driven recoupling sequence could be incorporated right after the selection of specific proton signals to monitor the intensity buildup for other proton signals. This enables the extraction of {sup 1}H-{sup 1}H distances between different pairs of protons. Therefore, we believe that the proposed method will greatly aid in fast assignment of peaks in proton spectra and will be useful in the development of proton-based multi-dimensional solid-state NMR experiments to study atomic-level resolution structure and dynamics of solids.

  7. Magnetic Resonance Imaging and Magnetic Resonance Spectroscopy in Dementias

    Hsu, Yuan-Yu; Du, An-Tao; Schuff, Norbert; Weiner, Michael W.

    2001-01-01

    This article reviews recent studies of magnetic resonance imaging and magnetic resonance spectroscopy in dementia, including Alzheimer's disease, frontotemporal dementia, dementia with Lewy bodies, idiopathic Parkinson's disease, Huntington's disease, and vascular dementia. Magnetic resonance imaging and magnetic resonance spectroscopy can detect structural alteration and biochemical abnormalities in the brain of demented subjects and may help in the differential diagnosis and early detection...

  8. Efficient isotropic magnetic resonators

    Martin, O. J. F.; Gay-Balmaz, P.

    2002-01-01

    We study experimentally and numerically a novel three-dimensional magnetic resonator structure with high isotropy. It is formed by crossed split-ring resonators and has a response independent of the illumination direction in a specific plane. The utilization of such elements to build a finite left-handed medium is discussed. (C) 2002 American Institute of Physics.

  9. Unambiguous assigning of the signals of the nuclear magnetic resonance spectra of {sup 1} H and {sup 13} C of monoterpenes using computational methods; Asignacion inequivoca de las senales del espectro de resonancia magnetica nuclear de {sup 1} H y {sup 13} C de monoterpenos empleando metodos computacionales

    Cortes, F.; Cuevas, G.; Tenorio, J.; Rochin, A.L. [Universidad Nacional Autonoma de Mexico, Instituto de Quimica, A.P. 70213, 04510 Mexico D.F. (Mexico)

    2000-07-01

    Ab initio calculations, within the frame of Density Functional Theory were carried out on camphene and {alpha}-pinene. The {sup 1} H and {sup 13} C shifts were estimated according to the recently developed Sum-Over-States Density Functional Perturbation Theory (SOS-DFPT) as implemented in a modified deMon-KS program. The calculations not only reproduced the observed NMR chemical shifts, quantitatively in the case of {sup 1} H nuclei and qualitatively in the case of {sup 13} C nuclei, but also allow assigning unambiguously the signal on these spectra. (Author)

  10. GHz nuclear magnetic resonance

    Cross, T.A.; Drobny, G.; Trewhella, J.

    1994-12-01

    For the past dozen years, 500- and 600-MHz spectrometers have become available in many laboratories. The first 600-MHz NMR spectrometer (at Carnegie Mellon University) was commissioned more than 15 years ago and, until 1994, represented the highest field available for high-resolution NMR. This year, we have witnessed unprecedented progress in the development of very high field magnets for NMR spectroscopy, including the delivery of the first commercial 750-MHz NMR spectrometers. In addition, NMR signals have been obtained from 20-Tesla magnets (850 MHz for {sup 1}H`s) at both Los Alamos National Laboratory and Florida State University in the NHMFL (National High Magnetic Field Laboratory). These preliminary experiments have been performed in magnets with 100-ppm homogeneity, but a 20-Tesla magnet developed for the NHMFL will be brought to field this year with a projected homogeneity of 0.1 ppm over a 1-cm-diam spherical volume.

  11. Advances in magnetic resonance 10

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 10, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters that examine superoperators in magnetic resonance; ultrasonically modulated paramagnetic resonance; and the utility of electron paramagnetic resonance (EPR) and electron-nuclear double-resonance (ENDOR) techniques for studying low-frequency modes of atomic fluctuations and their significance for understanding the mechanism of structural phase transitions in solids.

  12. 23Na and 1H NMR Relaxometry of Shale at High Magnetic Field

    Yang, Donghan

    2016-01-01

    Formation evaluation of unconventional reservoirs is challenging due to the coexistence of different phases such as kerogen, bitumen, movable and bound light hydrocarbon and water. Current low-frequency (0.05 T) nuclear magnetic resonance (NMR) laboratory and logging methods are incapable of quantitatively separating the different phases. We demonstrate the utility of high-field (9 T) NMR 2D T1-T2 measurements for separating hydrocarbon and the clay-interacting aqueous phases in shale based on the difference in the frequency dependence of the spin-lattice relaxation time. Furthermore, we demonstrate 23Na NMR as a promising complementary technique to conventional 1H NMR for shale fluid typing, taking advantage of the fact that sodium ions are only present in the aqueous phase. We validate high-field (9 T) 23Na-1H NMR relaxometry for assessing brine-filled porosity and brine salinity in various porous materials, including porous glass, conventional rocks, clays, and shale, and apply it for differentiating hydro...

  13. A conformational study of the adducts of 2'-deoxythymidine and 2,2,6,6-tetramethyl-1,4-piperidone-N-oxyl by sup(1)H and sup(13)C nuclear magnetic resonance

    γ-Irradiation of oxygen-free, aqueous solutions of 2'-deoxythymidine in the presence of the organic nitroxide free radical, 2,2,6,6-tetramethyl-1,4-piperidone-N-oxyl (TAN) leads to a complex mixture of products in which the TAN moiety is linked to the C5 or C6 position of a 5,6-saturated thymine ring. Extensive sup(1)H and sup(13)C nmr data are provided for the eight TAN-dT adducts which are produced in the largest amounts. The results show that the conformational properties of the sugar moiety are dependent on the point of attachment of the TAN group and the configuration of the standard thymine ring

  14. 轻度认知功能障碍和轻度Alzheimer病的1H-MRS研究%Brain proton magnetic resonance spectroscopy in mild cognitive impairment and mild Alzheimer disease

    丁萍; 苗华栋; 嵇鸣; 魏文石

    2008-01-01

    目的 探讨质子磁共振波谱(1H-MRS)对轻度认知功能障碍(MCI)和轻度Alzheimer病(AD)的诊断和鉴别诊断的作用.方法 采用刺激回波序列(STEAM),对30例MCI患者、30例轻度AD患者和30例性别、年龄、文化程度匹配健康对照的双侧内侧颞叶1H-MRS进行分析,比较各组间N-乙酰天门冬氨酸/肌酸(NAA/Cr)、胆碱,肌酸(Cho/Cr)和肌醇/肌酸(MI/Cr)、N-乙酰天门冬氨酸/肌醇(NAA/MI)比值及不对称指数的差别,并对MCI和轻度AD组的简易智能精神状态量表(MMSE)评分与NAA/Cr、Cho/Cr、MI/Cr、NAA/MI进行相关分析. 结果 MCI组的左侧NAA/Cr及轻度AD组的两侧NAA/Cr显著低于对照组(P<0.05),MCI组和轻度AD组的两侧NAA/Cr无显著差异(P>0.05).三组间的Cho/Cr无差异(P>0.05).MCI组和轻度AD组的两侧MI/Cr显著高于对照组(P<0.05),MCI组和轻度AD组的左侧MI/Cr有显著差异(P<0.05).MCI组和轻度AD组的两侧NAA/MI显著低于对照组(P<0.05),MCI组和轻度AD组的左侧NAA/MI有显著差异(P<0.05).MCI、轻度AD和对照组的NAA/Cr、MI/Cr、NAA/MI有一定的左侧偏性,但三组之间的代谢物不对称指数无显著差异(P>0.05).MCI和轻度AD两组的MMSE评分与两侧NAA/Cr明显正相关(P0.<05).轻度AD组的MMSE评分与右NAA/MI明显正相关(P<0.05).两组合并的MMSE评分与左NAA/Cr、MI/Cr、NAA/MI明显正相关(P<0.05).结论 MCI、轻度AD患者内侧颞叶NAA/Cr、NAA/MI比值的降低与MI/Cr比值的升高,以及MCI和轻度AD患者的左侧MI/Cr、NAA/MI有显著差异,为MCI和AD的早期诊断和鉴别诊断提供参考.MCI和轻度AD患者NAA/Cr、NAA/MI的变化与痴呆严重程度的相关性,对MCI和AD的疾病进展和治疗监测有重要作用.1H-MRS是MCI和AD的诊断、鉴别诊断和疾病监测的有用工具.

  15. Functional Magnetic Resonance Imaging

    Voos, Avery; Pelphrey, Kevin

    2013-01-01

    Functional magnetic resonance imaging (fMRI), with its excellent spatial resolution and ability to visualize networks of neuroanatomical structures involved in complex information processing, has become the dominant technique for the study of brain function and its development. The accessibility of in-vivo pediatric brain-imaging techniques…

  16. Resonant magnetic vortices

    By using the complex angular momentum method, we provide a semiclassical analysis of electron scattering by a magnetic vortex of Aharonov-Bohm type. Regge poles of the S matrix are associated with surface waves orbiting around the vortex and supported by a magnetic field discontinuity. Rapid variations of sharp characteristic shapes can be observed on scattering cross sections. They correspond to quasibound states which are Breit-Wigner-type resonances associated with surface waves and which can be considered as quantum analogues of acoustic whispering-gallery modes. Such a resonant magnetic vortex could provide a different kind of artificial atom while the semiclassical approach developed here could be profitably extended in various areas of the physics of vortices

  17. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... during MRI, but this is rarely a problem. Tooth fillings and braces usually are not affected by ... Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic Resonance Imaging ( ...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) ... conditions such as: brain tumors stroke infections developmental anomalies hydrocephalus — dilatation of fluid spaces within the brain ( ...

  19. Magnetic Resonance Imaging (MRI) Safety

    ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) Safety What is MRI and how does ... What is MRI and how does it work? Magnetic resonance imaging, or MRI, is a way of obtaining very ...

  20. Magnetic resonance of phase transitions

    Owens, Frank J; Farach, Horacio A

    1979-01-01

    Magnetic Resonance of Phase Transitions shows how the effects of phase transitions are manifested in the magnetic resonance data. The book discusses the basic concepts of structural phase and magnetic resonance; various types of magnetic resonances and their underlying principles; and the radiofrequency methods of nuclear magnetic resonance. The text also describes quadrupole methods; the microwave technique of electron spin resonance; and the Mössbauer effect. Phase transitions in various systems such as fluids, liquid crystals, and crystals, including paramagnets and ferroelectrics, are also

  1. Intermolecular interactions in nuclear magnetic resonance: medium shifts of the 1H and 13C nuclei in methane in the gas phase and in solution and of gaseous 3He

    An analysis has been carried out of the continuum and the binary collision models used in the description of NMR solvent shifts caused by Van der Waals intermolecular interactions. The basic assumption underlying the models, i.e. σ sub(w)= -BE2 (I) is examined. The possible effects on I of such phenomena as B anisotropy and field gradients are discussed, as well as the inadequacy of I in representing the true intermolecular shielding. A new expression for E2 is proposed, which in connection with I forms the bais of a modified binary collision model. The new E2 expression takes into account the dynamic character of the interaction. The major obstacle to the binary collision model, the requirement for accurate parameters for the intermolecular potential employed in the statistical-mechanical averaging, is alleviated by the establishment of priority rules to be used in the selection of these paramters. The proposed binary collision model and a collision model are used to interpret the 1H and 13C medium shifts of methane in the gas phase and in solution. The proton shift data conform equally well to either model; the 13C data indicate that a large solvent-dependent term contributes to the observed medium shifts in addition to I. Proton and 13C B parameters of methane in the gas phase and in solution are discussed. Preliminary results of 3He medium shifts as a function of gas density are presented. An extracted B parameter based on the proposed binary collision model appears to agree well with the result of a quantum-mechanical calculation of B for a 3He atom in a uniform static electric field. (LL)

  2. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  3. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

  4. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head ... limitations of MRI of the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is ...

  5. Parallel Magnetic Resonance Imaging

    Uecker, Martin

    2015-01-01

    The main disadvantage of Magnetic Resonance Imaging (MRI) are its long scan times and, in consequence, its sensitivity to motion. Exploiting the complementary information from multiple receive coils, parallel imaging is able to recover images from under-sampled k-space data and to accelerate the measurement. Because parallel magnetic resonance imaging can be used to accelerate basically any imaging sequence it has many important applications. Parallel imaging brought a fundamental shift in image reconstruction: Image reconstruction changed from a simple direct Fourier transform to the solution of an ill-conditioned inverse problem. This work gives an overview of image reconstruction from the perspective of inverse problems. After introducing basic concepts such as regularization, discretization, and iterative reconstruction, advanced topics are discussed including algorithms for auto-calibration, the connection to approximation theory, and the combination with compressed sensing.

  6. Cavity- and waveguide-resonators in electron paramagnetic resonance, nuclear magnetic resonance, and magnetic resonance imaging.

    Webb, Andrew

    2014-11-01

    Cavity resonators are widely used in electron paramagnetic resonance, very high field magnetic resonance microimaging and also in high field human imaging. The basic principles and designs of different forms of cavity resonators including rectangular, cylindrical, re-entrant, cavity magnetrons, toroidal cavities and dielectric resonators are reviewed. Applications in EPR and MRI are summarized, and finally the topic of traveling wave MRI using the magnet bore as a waveguide is discussed. PMID:25456314

  7. Magnetic Resonance Facility (Fact Sheet)

    2012-03-01

    This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

  8. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... bear denotes child-specific content. Related Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  9. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful magnetic ... that are clearer and more detailed than other imaging methods. This exam does not use ionizing radiation ...

  10. Dental magnetic resonance imaging

    Growing distribution and utilization of digital volume tomography (DVT) extend the spectrum of clinical dental imaging. Additional diagnostic value, however, comes along with an increasing amount of radiation. In contrast, magnetic resonance imaging is a radiation free imaging technique. Furthermore, it offers a high soft tissue contrast. Morphological and numerical dental anomalies, differentiation of periapical lesions and exclusion of complications of dental diseases are field of applications for dental MRI. In addition, detection of caries and periodontal lesions and injury of inferior alveolar nerve are promising application areas in the future.

  11. Cranial magnetic resonance imaging

    Cranial Magnetic Resonance Imaging is comprehensive, well structured, and well written. The material is current and well referenced. The illustrations are good and complement the text well. The overall quality of publication is above average. The greatest attribute of the book is its readability. The author demonstrates ample skill in making complex subjects, such as MR physics and imaging of cerebral hemorrhage, easy to understand. The book closes with a detailed atlas on the anatomic appearance of the brain on MR images in the axial, coronal, and sagittal planes

  12. Magnetic resonance imaging equipments

    Magnetic resonance imaging (MRI) is a new examination technique used in diagnostic medicine. Its use has increased notably during the last few years in Finland, too. The biological effects of electromagnetic fields used in MRI are quite different from the effects of x-rays. This report introduces the physics and the techniques of MRI; the biological effects of magnetic fields and the hazards associated with the use of MRI systems are briefly discussed. The major national and international recommendations are summarized, too. Furthermore, a description is given how safety aspects are considered in Finnish MRI units. Finally, recommendations are given to restrict the exposure caused by MRI and to ensure the safe use of MRI. Diagnostic applications and clinical or economic aspects fall outside the scope of this report. (orig.)

  13. 3T磁共振氢质子波谱在骨与软组织肿瘤诊断中的应用价值%Application Value of 3T 1H-Magnetic Resonance Spectroscopy in Diagnosing Tumors of Bone and Soft Tissue

    齐滋华; 李传福; 马祥兴; 李振峰; 张凯; 于德新

    2011-01-01

    Objective To study benign and malignant bone and soft tissue tumors with H-magnetic resonance spectroscopy ( H-MRS) at 3 Tesla MR scanner and assess the value of H-MRS in diagnosing bone and soft tissue tumors and distinguishing benign from malignant tumors. Methods Totally 49 patients with clinically and pathologically confirmed bone and soft tissue tumors were enrolled in this study. H-MRS was performed before treatment with point-resolved spectroscopy sequence. The imaging characteristics of 'H-MRS for bone and soft tissue tumors were observed and the possible differences between benign and malignant tumors was compared. Since spectra were directly found under single-voxel proton MRS brain examination, the peak height of choline containing compounds ( Cho) opposite to the creatine ( Cr) and the Cho peak were observed, and then the malignancies of the tumors were judged. Cho/Cr value was calculated and used to distinguishing benign tumors from malignancies. Results 'H-MRS spectra of bone and soft tissue tumors were different from those of the normal muscles, and such difference also existed between benign and malignant tumors. The Cho\\peak disappeared or was extremely low among benign tumors. The Cho/Cr values of malignant tumors and benign tumors were 3. 13 ±0. 9 and 1. 34 ± 1. 02 , respectively ( P = 0. 02). Using 1.79 as the threshold value, the Cho/Cr value had sensitivity, specificity, and accuracy of 94% , 80% , and 90% , respectively, in diagnosing malignancies. Conclusions The increased Cho level, as measured by ' H-MRS, is related with the bone and soft tissue malignant tumor. Cho/Cr value is useful in distinguishing benign tumors from malignancies. H-MRS can be an important supplement to the conventional magnetic resonance imaging.%目的 应用超高场3T磁共振机对良、恶性骨与软组织肿瘤进行磁共振氢质子波谱(1 H-MRS)研究,探讨1 H-MRS对骨与软组织肿瘤的成像特点,及对良、恶性骨与软组织肿瘤鉴

  14. Effect of Exercise on the Creatine Resonances in 1H MR Spectra of Human Skeletal Muscle

    Kreis, R.; Jung, B.; Slotboom, J.; Felblinger, J.; Boesch, C.

    1999-04-01

    1H MR spectra of human muscles were recorded before, during, and after fatiguing exercise. In contrast to expectations, it was found that the spectral contributions of creatine/phosphocreatine (Cr/PCr) were subject to change as a function of exercise. In particular, the dipolar-coupled methylene protons of Cr/PCr were found to be reduced in intensity in proportion to the co-registered PCr levels. Recovery after exercise and behavior under ischemic conditions provide further evidence to suggest that the contributions of the CH2protons of Cr/PCr to1H MR spectra of human musclein vivoreflect PCr rather than Cr levels. Variation of experimental parameters showed that this effect is not due to a trivial change in relaxation times. At present it can only be speculated about why the Cr resonances have reduced NMR visibility. If temporary binding to macromolecules should be involved, the free Cr concentration-important for equilibrium calculations of the creatine kinase reaction-might be different from what was previously assumed.

  15. Advances in magnetic resonance 11

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 11, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains three chapters and begins with a discussion of the principles and applications of dynamic nuclear polarization, with emphasis on molecular motions and collisions, intermolecular couplings, and chemical interactions. Subsequent chapters focus on the assessment of a proposed broadband decoupling method and studies of time-domain (or Fourier transform) multiple-quantum nuclear magnetic resonance.

  16. Advances in magnetic resonance 6

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 6 focuses on the theoretical and practical aspects of applying magnetic resonance methods to various problems in physical chemistry, emphasizing the different aspects of the exegesis of these problems. This book discusses the gas phase magnetic resonance of electronically excited molecules; techniques for observing excited electronic states; NMR studies in liquids at high pressure; and effect of pressure on self-diffusion in liquids. The nuclear magnetic resonance investigations of organic free radicals; measurement of proton coupling constants by NMR; an

  17. Structural polymorphism in new organic-inorganic hybrid: Pyrazolium bromoantimonates(III) [C 3N 2H 5] 6Sb 4Br 18·2H 2O (tetragonal and triclinic forms). Thermal, dielectric and proton magnetic resonance ( 1H NMR) studies on the tetragonal form

    Piecha, A.; Białońska, A.; Jakubas, R.; Medycki, W.

    2008-11-01

    Two polymorphic forms of pyrazolium bromoantimonates(III) - [C 3N 2H 5] 6Sb 4Br 18·2H 2O: α modification - tetragonal form and β modification - triclinic form, have been synthesized and structurally characterized at 100 K. The α-polymorph consists of a unique three-dimensional (3D) anionic substructure built up of cyclic tetramers and discrete chains linked to each other, three nonequivalent pyrazolium cations and water molecules. The β-polymorph is characterized by discrete cyclic anionic tetramers [Sb 4Br 18] -6, three nonequivalent cations and water molecules. The physical properties have been studied for the [C 3N 2H 5] 6Sb 4Br 18·2H 2O (α form). The differential scanning calorimetry (DSC) revealed a complex sequence of phase transitions above room temperature. The low-frequency dielectric relaxation process was found to appear at low temperatures, which was assigned to the dynamics of dipolar pyrazolium cations. The molecular motions of the pyrazolium cations in the α-polymorph were studied in a wide temperature range by means of a proton magnetic resonance ( 1H NMR) technique. Two minima of the spin-lattice relaxation time ( T1) are disclosed: at low temperatures a wide one attributed to a small-angle-libration of cations and motion of water molecules, whereas the high temperature one assigned to the reorientation of cation about its pseudo-fivefold axis.

  18. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... or cause problems during an MRI exam. Nephrogenic systemic fibrosis is currently a recognized, but rare, complication ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  19. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... the same effect. A very irregular heartbeat may affect the quality of images obtained using techniques that ... Tumor Treatment Magnetic Resonance Imaging (MRI) Safety Alzheimer's Disease Head Injury Brain Tumors Images related to Magnetic ...

  20. MUSIC in Triple-Resonance Experiments: Amino Acid Type-Selective 1H- 15N Correlations

    Schubert, Mario; Smalla, Maika; Schmieder, Peter; Oschkinat, Hartmut

    1999-11-01

    Amino acid type-selective triple-resonance experiments can be of great help for the assignment of protein spectra, since they help to remove ambiguities in either manual or automated assignment procedures. Here, modified triple-resonance experiments that yield amino acid type-selective 1H-15N correlations are presented. They are based on novel coherence transfer schemes, the MUSIC pulse sequence elements, that replace the initial INEPT transfer and are selective for XH2 or XH3 (X can be 15N or 13C). The desired amino acid type is thereby selected based on the topology of the side chain. Experiments for Gly (G-HSQC); Ala (A-HSQC); Thr, Val, Ile, and Ala (TAVI-HSQC); Thr and Ala (TA-HSQC), as well as Asn and Gln (N-HSQC and QN-HSQC), are described. The new experiments are recorded as two-dimensional experiments and therefore need only small amounts of spectrometer time. The performance of the experiments is demonstrated with the application to two protein domains.

  1. MUSIC in triple-resonance experiments: amino acid type-selective (1)H-(15)N correlations

    Schubert; Smalla; Schmieder; Oschkinat

    1999-11-01

    Amino acid type-selective triple-resonance experiments can be of great help for the assignment of protein spectra, since they help to remove ambiguities in either manual or automated assignment procedures. Here, modified triple-resonance experiments that yield amino acid type-selective (1)H-(15)N correlations are presented. They are based on novel coherence transfer schemes, the MUSIC pulse sequence elements, that replace the initial INEPT transfer and are selective for XH(2) or XH(3) (X can be (15)N or (13)C). The desired amino acid type is thereby selected based on the topology of the side chain. Experiments for Gly (G-HSQC); Ala (A-HSQC); Thr, Val, Ile, and Ala (TAVI-HSQC); Thr and Ala (TA-HSQC), as well as Asn and Gln (N-HSQC and QN-HSQC), are described. The new experiments are recorded as two-dimensional experiments and therefore need only small amounts of spectrometer time. The performance of the experiments is demonstrated with the application to two protein domains. Copyright 1999 Academic Press. PMID:10527741

  2. The Value of Short Echo Time Proton Magnetic Resonance Spectroscopy in Differential Diagnosing Tumefactive Demyelinating Lesions and Astrocytomas%短TE1H-MRS β,γ-Glx峰鉴别脑内脱髓鞘假瘤和星形细胞瘤的价值

    罗海营; 黄飚; 刘红军; 张水兴; 王广谊

    2011-01-01

    Objective To evaluate the value of short echo time(TE)proton magnetic resonance spectroscopy(1H MRS)in differential diagnosing tmefactive demyelinating lesions(TDLs) and astrocytomas.Materials and Methods 42 cases were collected in this study.Of the 42 patients,23 patients with pathologically proved astrocytoma(7 WHO grade Ⅱ and 16 WHO grade Ⅲ - Ⅳ )and 19 patients with TDLs( 11 cases pathologically proved and 8 cases clinically proved with TDLs).Single voxel spectra at TE 35 ms( short TE)was used in all cases.Peak heights of creatine( Cr)and glutamate( Glu)/glutamine ( Gln ) ( β, γ-Glx) were measured, then β, γ-Glx/Cr ratios of corresponding regions in TDLs and astrocytoma were compared to pathological and clinic results.Results The mean ratio β,γ-Glx/Cr was 0.6205 ±0.15050 in TDLs group and 0.3048 ± 0.09563 in astrocytoma group.The mesnβ,γ-Glx/Cr ratio in TDLs was significantly higher than that of astrocytoma statistically(P < 0.05).Conclusion The ratios of β, γ-Glx/Cr at short TE provide valuable information to discriminate between TDLs and astrocytomas.%目的 采用短回波时间(TE)氢质子磁共振波谱(1H-MRS)提高对脑内脱髓鞘假瘤和星形细胞瘤鉴别诊断的准确性.资料与方法 19例脑内脱髓鞘假瘤,其中11例经手术证实,8例经临床证实;经手术证实的23例星形细胞瘤(其中WHOⅡ级8例,WHOⅢ-Ⅳ级15例),均行常规MRI和单体素短TE1H-MRS检查,分析短TE1H-MRS检查中病灶的β,γ-谷氨酸复合物(Glx)/肌酸(Cr)值,结果与病灶病理诊断或临床诊断结果进行相关分析.结果 脑内脱髓鞘假瘤组病灶区平均β,γ-Glx/Cr值为0.6205±0.15050;星形细胞瘤组病灶区的平均β,γ-Glx/Cr 值为0.3048±0.09563,两者之间差异有统计学意义(P<0.05).结论 脑内脱髓鞘假瘤组病灶区的β,γ-Glx/Cr 值明显高于星形细胞瘤组,短TE1H-MRS中β,γ-Glx峰的升高可以作为鉴别脑内脱髓鞘假瘤和星形细胞瘤的补充手段,据此有助

  3. Magnetic hyperthermia efficiency and (1)H-NMR relaxation properties of iron oxide/paclitaxel-loaded PLGA nanoparticles.

    Ruggiero, Maria R; Crich, Simonetta Geninatti; Sieni, Elisabetta; Sgarbossa, Paolo; Forzan, Michele; Cavallari, Eleonora; Stefania, Rachele; Dughiero, Fabrizio; Aime, Silvio

    2016-07-15

    Magnetic iron oxide nanoparticles (Fe-NPs) can be exploited in biomedicine as agents for magnetic fluid hyperthermia (MFH) treatments and as contrast enhancers in magnetic resonance imaging. New, oleate-covered, iron oxide particles have been prepared either by co-precipitation or thermal decomposition methods and incorporated into poly(lactic-co-glycolic acid) nanoparticles (PLGA-Fe-NPs) to improve their biocompatibility and in vivo stability. Moreover, the PLGA-Fe-NPs have been loaded with paclitaxel to pursue an MFH-triggered drug release. Remarkably, it has been found that the nanoparticle formulations are characterized by peculiar (1)H nuclear magnetic relaxation dispersion (NMRD) profiles that directly correlate with their heating potential when exposed to an alternating magnetic field. By prolonging the magnetic field exposure to 30 min, a significant drug release was observed for PLGA-Fe-NPs in the case of the larger-sized magnetic nanoparticles. Furthermore, the immobilization of lipophilic Fe-NPs in PLGA-NPs also made it possible to maintain Néel relaxation as the dominant relaxation contribution in the presence of large iron oxide cores (diameters of 15-20 nm), with the advantage of preserving their efficiency when they are entrapped in the intracellular environment. The results reported herein show that NMRD profiles are a useful tool for anticipating the heating capabilities of Fe-NPs designed for MFH applications. PMID:27265726

  4. Magnetic hyperthermia efficiency and 1H-NMR relaxation properties of iron oxide/paclitaxel-loaded PLGA nanoparticles

    Ruggiero, Maria R.; Geninatti Crich, Simonetta; Sieni, Elisabetta; Sgarbossa, Paolo; Forzan, Michele; Cavallari, Eleonora; Stefania, Rachele; Dughiero, Fabrizio; Aime, Silvio

    2016-07-01

    Magnetic iron oxide nanoparticles (Fe-NPs) can be exploited in biomedicine as agents for magnetic fluid hyperthermia (MFH) treatments and as contrast enhancers in magnetic resonance imaging. New, oleate-covered, iron oxide particles have been prepared either by co-precipitation or thermal decomposition methods and incorporated into poly(lactic-co-glycolic acid) nanoparticles (PLGA-Fe-NPs) to improve their biocompatibility and in vivo stability. Moreover, the PLGA-Fe-NPs have been loaded with paclitaxel to pursue an MFH-triggered drug release. Remarkably, it has been found that the nanoparticle formulations are characterized by peculiar 1H nuclear magnetic relaxation dispersion (NMRD) profiles that directly correlate with their heating potential when exposed to an alternating magnetic field. By prolonging the magnetic field exposure to 30 min, a significant drug release was observed for PLGA-Fe-NPs in the case of the larger-sized magnetic nanoparticles. Furthermore, the immobilization of lipophilic Fe-NPs in PLGA-NPs also made it possible to maintain Néel relaxation as the dominant relaxation contribution in the presence of large iron oxide cores (diameters of 15–20 nm), with the advantage of preserving their efficiency when they are entrapped in the intracellular environment. The results reported herein show that NMRD profiles are a useful tool for anticipating the heating capabilities of Fe-NPs designed for MFH applications.

  5. Magnetic resonance in neuroborreliosis

    Magnetic resonance (MR) is commonly used in diagnosing infections of the central nervous system. The aim of the study is to evaluate central nervous system changes in neuroborreliosis patients. MR examinations were performed in 44 patients with clinical symptoms, epidemiology and laboratory tests results of neuroborreliosis. Abnormalities were detected in 22 patients. Most of them presented cortico-subcortical atrophy (86%). In 9 cases foci of increased signal in T2-weighted and FLAIR images were observed in white matter. They were single or multiple, located subcorticaly and paraventriculary. In 2 subjects areas of increased signal were found in the brain stem. Central nervous system abnormalities detected with MR are not specific for Lyme disease. They can suggest demyelinating lesions and/or gliosis observed in many nervous system disorders (SM, ADEM, lacunar infarcts). (author)

  6. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a ...

  7. Advances in magnetic resonance 12

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 12, presents a variety of contributions to the theory and practice of magnetic resonance. The book contains six chapters and begins with a discussion of diffusion and self-diffusion measurements by nuclear magnetic resonance. This is followed by separate chapters on spin-lattice relaxation time in hydrogen isotope mixtures; the principles of optical detection of nuclear spin alignment and nuclear quadropole resonance; and the spin-1 behavior, including the relaxation of the quasi-invariants of the motion of a system of pairs of dipolar coupled spin-1/2 nu

  8. 15N-{1H} NOE experiment at high magnetic field strengths

    The heteronuclear 15N-{1H} NOE values are typically determined by taking the ratio of 15N signal intensities recorded in the presence and absence of 1H saturation prior to evolution of 15N magnetization. Since the intensity ratio of two independent experiments is taken, complete recovery of 15N magnetization during the scan repetition delay is critical to obtain reliable NOE values. Because it may not be practical to wait for the complete recovery of magnetization at high magnetic fields, Solomon equations may be used to correct measured NOE values. Here, based on experiments and simulations, we show that since the cross-correlation between 1H-15N dipole and 15N chemical shift anisotropy becomes significant at high fields for small or deuterated proteins, measured NOE values can not be accurately corrected based on the Solomon equations. We also discuss ranges of rotational correlation times and proton spin-flip rate, in which the NOE values can be corrected by the equations

  9. Magnetic resonance imaging methodology

    Magnetic resonance (MR) methods are non-invasive techniques to provide detailed, multi-parametric information on human anatomy, function and metabolism. Sensitivity, specificity, spatial and temporal resolution may, however, vary depending on hardware (e.g., field strength, gradient strength and speed) and software (optimised measurement protocols and parameters for the various techniques). Furthermore, multi-modality imaging may enhance specificity to better characterise complex disease patterns. Positron emission tomography (PET) is an interesting, largely complementary modality, which might be combined with MR. Despite obvious advantages, combining these rather different physical methods may also pose challenging problems. At this early stage, it seems that PET quality may be preserved in the magnetic field and, if an adequate detector material is used for the PET, MR sensitivity should not be significantly degraded. Again, this may vary for the different MR techniques, whereby functional and metabolic MR is more susceptible than standard anatomical imaging. Here we provide a short introduction to MR basics and MR techniques, also discussing advantages, artefacts and problems when MR hardware and PET detectors are combined. In addition to references for more detailed descriptions of MR fundamentals and applications, we provide an early outlook on this novel and exciting multi-modality approach to PET/MR. (orig.)

  10. Magnetic Resonance angiography. Pt 1

    The objective of this paper is to describe the basic physical principles important in magnetic resonance angiography (MRA). The data used were obtained from recent articles on MRA and direct experience working with prototype MRA sequence. The information is presented in a manner suitable for those unfamiliar with the principles of MRA and magnetic resonance imaging (MRI). Magnetic resonance angiography is an important method that can be used to obtain angiograms without the injection of intravascular contrast medium. It is already proving to be of clinical use in the assessment of vascular disease. 11 refs., 5 figs

  11. Advances in magnetic resonance 9

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 9 describes the magnetic resonance in split constants and dipolar relaxation. This book discusses the temperature-dependent splitting constants in the ESR spectra of organic free radicals; temperature-dependent splittings in ion pairs; and magnetic resonance induced by electrons. The electron impact excitation of atoms and molecules; intramolecular dipolar relaxation in multi-spin systems; and dipolar cross-correlation problem are also elaborated. This text likewise covers the NMR studies of molecules oriented in thermotropic liquid crystals and diffusion

  12. Advances in magnetic resonance 1

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 1, discusses developments in various areas of magnetic resonance. The subject matter ranges from original theoretical contributions through syntheses of points of view toward series of phenomena to critical and painstaking tabulations of experimental data. The book contains six chapters and begins with a discussion of the theory of relaxation processes. This is followed by separate chapters on the development of magnetic resonance techniques for studying rate processes in chemistry and the application of these techniques to various problems; the geometri

  13. Functional magnetic resonance imaging.

    Buchbinder, Bradley R

    2016-01-01

    Functional magnetic resonance imaging (fMRI) maps the spatiotemporal distribution of neural activity in the brain under varying cognitive conditions. Since its inception in 1991, blood oxygen level-dependent (BOLD) fMRI has rapidly become a vital methodology in basic and applied neuroscience research. In the clinical realm, it has become an established tool for presurgical functional brain mapping. This chapter has three principal aims. First, we review key physiologic, biophysical, and methodologic principles that underlie BOLD fMRI, regardless of its particular area of application. These principles inform a nuanced interpretation of the BOLD fMRI signal, along with its neurophysiologic significance and pitfalls. Second, we illustrate the clinical application of task-based fMRI to presurgical motor, language, and memory mapping in patients with lesions near eloquent brain areas. Integration of BOLD fMRI and diffusion tensor white-matter tractography provides a road map for presurgical planning and intraoperative navigation that helps to maximize the extent of lesion resection while minimizing the risk of postoperative neurologic deficits. Finally, we highlight several basic principles of resting-state fMRI and its emerging translational clinical applications. Resting-state fMRI represents an important paradigm shift, focusing attention on functional connectivity within intrinsic cognitive networks. PMID:27432660

  14. A hyperpolarized equilibrium for magnetic resonance

    Hövener, Jan-Bernd; Schwaderlapp, Niels; Lickert, Thomas; Duckett, Simon B.; Mewis, Ryan E.; Highton, Louise A. R.; Kenny, Stephen M.; Green, Gary G. R.; Leibfritz, Dieter; Korvink, Jan G.; Hennig, Jürgen; von Elverfeldt, Dominik

    2013-12-01

    Nuclear magnetic resonance spectroscopy and imaging (MRI) play an indispensable role in science and healthcare but use only a tiny fraction of their potential. No more than ≈10 p.p.m. of all 1H nuclei are effectively detected in a 3-Tesla clinical MRI system. Thus, a vast array of new applications lays dormant, awaiting improved sensitivity. Here we demonstrate the continuous polarization of small molecules in solution to a level that cannot be achieved in a viable magnet. The magnetization does not decay and is effectively reinitialized within seconds after being measured. This effect depends on the long-lived, entangled spin-order of parahydrogen and an exchange reaction in a low magnetic field of 10-3 Tesla. We demonstrate the potential of this method by fast MRI and envision the catalysis of new applications such as cancer screening or indeed low-field MRI for routine use and remote application.

  15. Magnetic resonance energy and topological resonance energy.

    Aihara, Jun-Ichi

    2016-04-28

    Ring-current diamagnetism of a polycyclic π-system is closely associated with thermodynamic stability due to the individual circuits. Magnetic resonance energy (MRE), derived from the ring-current diamagnetic susceptibility, was explored in conjunction with graph-theoretically defined topological resonance energy (TRE). For many aromatic molecules, MRE is highly correlative with TRE with a correlation coefficient of 0.996. For all π-systems studied, MRE has the same sign as TRE. The only trouble with MRE may be that some antiaromatic and non-alternant species exhibit unusually large MRE-to-TRE ratios. This kind of difficulty can in principle be overcome by prior geometry-optimisation or by changing spin multiplicity. Apart from the semi-empirical resonance-theory resonance energy, MRE is considered as the first aromatic stabilisation energy (ASE) defined without referring to any hypothetical polyene reference. PMID:26878709

  16. Magnetic resonance spectroscopy: clinical application in neuroradiology

    Full text: Magnetic Resonance Spectroscopy (MRS) provides a non-invasive method of studying metabolism in vivo. Magnetic resonance spectroscopy (MRS) defines neuro chemistry on a regional basis by acquiring a radiofrequency signal with chemical shift from one or many voxels or volumes previously selected on MRI. The tissue's chemical environment determines the frequency of a metabolite peak in an MRS spectrum. Candidates for MRS include: 1H, 31P, 13C, 23Na, 7Li, 19F, 14N, 15N, 17O, 39K The most commonly studied nuclei are 1H and 31P. This lecture is focused on Proton (1H) Spectroscopy. Proton MRS can be added on to conventional MR imaging protocols. It can be used to serially monitor biochemical changes in tumors, stroke, epilepsy, metabolic disorders, infections, and neurodegenerative diseases.The MR spectra do not come labeled with diagnoses. They require interpretation and should always be correlated with the MR images before making a final diagnosis. As a general rule, the single voxel, short TE technique is used to make the initial diagnosis, because the signal-to-noise is high and all metabolites are represented. Multi-voxel, long TE techniques are used to further characterize different regions of a mass and to assess brain parenchyma around or adjacent to the mass. Multi-voxel, long TE techniques are also used to assess response to therapy and to search for tumor recurrence. Each metabolite appears at a specific ppm, and each one reflects specific cellular and biochemical processes

  17. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... is not harmful, but it may cause some medical devices to malfunction. Most orthopedic implants pose no ... Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose and treat ...

  19. Magnetic resonance imaging the basics

    Constantinides, Christakis

    2014-01-01

    Magnetic resonance imaging (MRI) is a rapidly developing field in basic applied science and clinical practice. Research efforts in this area have already been recognized with five Nobel prizes awarded to seven Nobel laureates in the past 70 years. Based on courses taught at The Johns Hopkins University, Magnetic Resonance Imaging: The Basics provides a solid introduction to this powerful technology. The book begins with a general description of the phenomenon of magnetic resonance and a brief summary of Fourier transformations in two dimensions. It examines the fundamental principles of physics for nuclear magnetic resonance (NMR) signal formation and image construction and provides a detailed explanation of the mathematical formulation of MRI. Numerous image quantitative indices are discussed, including (among others) signal, noise, signal-to-noise, contrast, and resolution. The second part of the book examines the hardware and electronics of an MRI scanner and the typical measurements and simulations of m...

  20. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... Magnetic resonance imaging (MRI) is a noninvasive medical test that physicians use to diagnose and treat medical ... CD. Currently, MRI is the most sensitive imaging test of the head (particularly the brain) in routine ...

  1. Kinetics of the in vivo31P 1H nuclear overhauser effect of the human-calf-muscle phosphocreatine resonance

    Bachert, Peter; Bellemann, Matthias E.

    In 31P 1H double-resonance experiments in a 1.5 T whole-body MR system, we observed in vivo the truncated driven, transient, and steady-state 31P- 1H nuclear Overhauser effect of the phosphocreatine resonance in 31P MR spectra of human gastrocnemius muscle. Maximum signal enhancements of 0.52 ± 0.01, 0.20 ± 0.01, and 0.79 ± 0.02 were measured, respectively. Fitting the data with theoretical functions which solve the multispin Solomon equations for N protons (S spins) dipolar coupled to a 31P nucleus (I spin) yields cross-relaxation times {2}/{[Σ i=1-N σIS(i) ] } in the order of 20 s. In vivo experiments are feasible for studying relaxation mechanisms in coupled 31P 1H spin systems in intact tissue.

  2. Magnetic Resonance Connectome Automated Pipeline

    Gray, William R.; Bogovic, John A.; Vogelstein, Joshua T; Landman, Bennett A.; Prince, Jerry L.; Vogelstein, R. Jacob

    2011-01-01

    This manuscript presents a novel, tightly integrated pipeline for estimating a connectome, which is a comprehensive description of the neural circuits in the brain. The pipeline utilizes magnetic resonance imaging (MRI) data to produce a high-level estimate of the structural connectivity in the human brain. The Magnetic Resonance Connectome Automated Pipeline (MRCAP) is efficient and its modular construction allows researchers to modify algorithms to meet their specific requirements. The pipe...

  3. Advances in magnetic resonance 2

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 2, features a mixture of experimental and theoretical contributions. The book contains four chapters and begins with an ambitious and general treatment of the problem of signal-to-noise ratio in magnetic resonance. This is followed by separate chapters on the interpretation of nuclear relaxation in fluids, with special reference to hydrogen; and various aspects of molecular theory of importance in NMR.

  4. Advances in magnetic resonance 4

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 4 deals with the relaxation, irradiation, and other dynamical effects that is specific to systems having resolved structure in their magnetic resonance spectra. This book discusses the anisotropic rotation of molecules in liquids by NMR quadrupolar relaxation; rotational diffusion constants; alternating linewidth effect; and theoretical formulations of the problem. The line shapes in high-resolution NMR; matrix representations of the equations of motion; matrix representations of the equations of motion; and intramolecular hydrogen bonds are also delibera

  5. Nuclear magnetic gamma double resonance

    A number of problems corresponding to different variants of experiments using nuclear magnetic-gamma double resonance (NMGDR) are theoretically investigated. Calculation is carried out and its results are compared to experimental ones concerning NMGDR for tantalum. Time dynamics of the source or scatterer nucleus sublevel populations under double resonance conditions with non-uniform initial population of this nucleus sublevels is studied

  6. Magnetic resonance imaging; Imagerie par resonance magnetique

    Fontanel, F. [Centre Hospitalier, 40 - Mont-de -Marsan (France); Clerc, T. [Centre Hospitalier Universitaire, 76 - Rouen (France); Theolier, S. [Hospice Civils de Lyon, 69 - Lyon (France); Verdenet, J. [Centre Hospitalier Universitaire, 25 - Besancon (France)

    1997-04-01

    The last improvements in nuclear magnetic resonance imaging are detailed here, society by society with an expose of their different devices. In the future the different technological evolutions will be on a faster acquisition, allowing to reduce the examination time, on the development of a more acute cardiac imaging, of a functional neuro-imaging and an interactive imaging for intervention. With the contrast products, staying a longer time in the vascular area, the angiography will find its place. Finally, the studies on magnetic fields should allow to increase the volume to examine. (N.C.).

  7. Magnetic Resonance Imaging of Thoracic Aortic Dissections

    Sax, Steven L.

    1990-01-01

    Magnetic resonance imaging is an excellent noninvasive method for evaluating thoracic aortic dissections. A variety of magnetic resonance scans of aortic dissections are shown, documenting the ability of magnetic resonance to image the true lumen, the false channel, and the intimal septum. Detail is provided on magnetic resonance imaging techniques and findings. (Texas Heart Institute Journal 1990;17:262-70)

  8. Advances in magnetic resonance 5

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 5 deals with the interpretation of ESR spectra and provides descriptions of experimental apparatus. This book discusses the halogen hyperfine interactions; organic radicals in single crystals; pulsed-Fourier-transform nuclear magnetic resonance spectrometer; and inhomogenizer and decoupler. The spectrometers for multiple-pulse NMR; weak collision theory of relaxation in the rotating frame; and spin Hamiltonian for the electron spin resonance of irradiated organic single crystals are also deliberated. This text likewise covers the NMR in helium three and m

  9. Reproducibility of 3.0 Tesla magnetic resonance spectroscopy for measuring hepatic fat content

    J.R. van Werven; J.M. Hoogduin; A.J. Nederveen; A.A. van Vliet; E. Wajs; P. Vandenberk; E.S.G. Stroes; J. Stoker

    2009-01-01

    PURPOSE: To investigate reproducibility of proton magnetic resonance spectroscopy ((1)H-MRS) to measure hepatic triglyceride content (HTGC). MATERIALS AND METHODS: In 24 subjects, HTGC was evaluated using (1)H-MRS at 3.0 Tesla. We studied "between-weeks" reproducibility and reproducibility of (1)H-M

  10. Magnetic resonance and porous materials

    Mention the words magnetic resonance to your medical advisor and he or she will immediately think of a multi-million pound scanner that peers deep into the brain. A chemist, on the other hand, will imagine a machine that costs several hundred thousand pounds and produces high-resolution spectra for chemical analysis. Food technologists will probably think of a bench-top instrument for determining moisture content, while an oil prospector will envisage a device that can be operated several kilometres down an oil well. To a physicist the term is more likely to conjure up a mental picture of nuclear spins precessing in a magnetic field. These examples illustrate the diverse aspects of a phenomenon discovered by physicists over 50 years ago. Electron spin resonance was first discovered by Russian scientists, and nuclear magnetic resonance was discovered in the US shortly afterwards by Ed Purcell at Harvard University and Felix Bloch at Stanford University. Today, nuclear magnetic resonance (NMR) is the most widely used technique. Modern NMR machines are making it possible to probe microstructure and molecular movement in materials as diverse as polymers, cements, rocks, soil and foods. NMR allows the distribution of different components in a material to be determined with a resolution approaching 1μm, although the signal can be sensitive to even smaller lengthscales. In this article the authors describe how physicists are still developing magnetic resonance to exploit a range of new applications. (UK)

  11. 无痴呆型血管性认知障碍患者多体素质子磁共振波谱的诊断价值%A study of multi-voxel 1H-magnetic resonance spectroscopy in patients with vascular cognitive impairment no dementia

    刘娟; 李文; 王润榕; 沈钧康; 王琦; 杨毅; 赵合庆; 刘春风

    2010-01-01

    目的 探讨多体素质子磁共振波谱(1H-MRS)在无痴呆型血管性认知障碍(VCIND)早期诊断中的价值.方法 入选2008年12月至2009年9月本院门诊及住院患者共78例,完成成套神经心理学测验,包括北京版蒙特利尔认知量表(MoCA)、听觉词语学习测验(AVLT)、数字广度测验(DST)、Rey-Osterrieth复杂图形测验(CFT)、语义与语音流畅试验、数字符号编码测验(DSCT)、连线测验(TMT)、画钟测验(CDT)和Stroop色词测验(SCWT).根据测验成绩分为VCIND组和认知正常对照组,从中选择性别、年龄、文化程度匹配者各18例,利用多体素1H-MRS检测双侧额、颞、顶叶及丘脑灰质区N-乙酰天冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)水平,比较两组间NAA/Cr、Cho/Cr比值的差别;同时,对VCIND组患者MoCA总分及其有认知损害的子项评分与NAA/Cr、Cho/Cr比值进行相关分析.所有入选对象对试验方案均知情同意,本试验通过伦理委员会批准.结果 VCIND组患者左、右两侧丘脑灰质区NAA/Cr比值与对照组比较均明显下降(左侧1.56±0.49、1.89±0.48,F=11.222,P=0.002;右侧1.63±0.45、1.86±0.33,F=5.358,P=0.027);两组间额、颞、顶叶NAA/Cr比值以及所有区域Cho/Cr比值均无统计学意义.VCIND组患者左、右两侧NAA/Cr下降程度与MoCA评分(r=0.54、0.44)及记忆力(r=0.61、0.49)、注意力(r=0.43、0.36)、语言功能(r=0.39、0.31)、视空间与执行能力(r=0.29、0.33)等子项评分均呈正相关(均P<0.05或P<0.01).结论 VCIND患者认知功能损害可能与双侧丘脑神经元代谢异常有关,多体素1H-MRS在VCIND早期诊断和病情进展监测中起着重要的作用.%Objective To evaluate the roles of multi-voxel proton magnetic resonance spectroscopy (1H-MRS) in the early diagnosis of vascular cognitive impairment no dementia (VCIND).Methods Seventy-eight out-patients and inpatients in Department of Neurology, the second Affiliated Hospital of Soochow University

  12. Nanodiamond graphitization: a magnetic resonance study

    We report on the first nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) study of the high-temperature nanodiamond-to-onion transformation. 1H, 13C NMR and EPR spectra of the initial nanodiamond samples and those annealed at 600, 700, 800 and 1800 ° C were measured. For the samples annealed at 600 to 800 ° C, our NMR data reveal the early stages of the surface modification, as well as a progressive increase in sp2 carbon content with increased annealing temperature. Such quantitative experimental data were recorded for the first time. These findings correlate with EPR data on the sensitivity of the dangling bond EPR line width to air content, progressing with rising annealing temperature, that evidences consequent graphitization of the external layers of the diamond core. The sample annealed at 1800 ° C shows complete conversion of nanodiamond particles into carbon onions. (paper)

  13. NMR resonance splitting of urea in stretched hydrogels: proton exchange and (1)H/(2)H isotopologues.

    Kuchel, Philip W; Naumann, Christoph; Chapman, Bogdan E; Shishmarev, Dmitry; Håkansson, Pär; Bacskay, George; Hush, Noel S

    2014-10-01

    Urea at ∼12 M in concentrated gelatin gel, that was stretched, gave (1)H and (2)H NMR spectral splitting patterns that varied in a predictable way with changes in the relative proportions of (1)H2O and (2)H2O in the medium. This required consideration of the combinatorics of the two amide groups in urea that have a total of four protonation/deuteration sites giving rise to 16 different isotopologues, if all the atoms were separately identifiable. The rate constant that characterized the exchange of the protons with water was estimated by back-transformation analysis of 2D-EXSY spectra. There was no (1)H NMR spectral evidence that the chiral gelatin medium had caused in-equivalence in the protons bonded to each amide nitrogen atom. The spectral splitting patterns in (1)H and (2)H NMR spectra were accounted for by intra-molecular scalar and dipolar interactions, and quadrupolar interactions with the electric field gradients of the gelatin matrix, respectively. PMID:25241007

  14. magnetic resonance imaging,etc.

    张福基

    1998-01-01

    magnetic resonance imaging n.[1984] a noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within he body induced by the application of radio waves磁共振成像(指一种非侵害 性诊断技术,能生成内部身体组织的计算机化影像,其依据是应用无线电波 感生体内原子并使之产磁共振)

  15. Accelerated nanoscale magnetic resonance imaging through phase multiplexing

    We report a method for accelerated nanoscale nuclear magnetic resonance imaging by detecting several signals in parallel. Our technique relies on phase multiplexing, where the signals from different nuclear spin ensembles are encoded in the phase of an ultrasensitive magnetic detector. We demonstrate this technique by simultaneously acquiring statistically polarized spin signals from two different nuclear species (1H, 19F) and from up to six spatial locations in a nanowire test sample using a magnetic resonance force microscope. We obtain one-dimensional imaging resolution better than 5 nm, and subnanometer positional accuracy

  16. Accelerated nanoscale magnetic resonance imaging through phase multiplexing

    Moores, B. A.; Eichler, A., E-mail: eichlera@phys.ethz.ch; Takahashi, H.; Navaretti, P.; Degen, C. L. [Department of Physics, ETH Zurich, Otto-Stern-Weg 1, 8093 Zurich (Switzerland); Tao, Y. [Department of Physics, ETH Zurich, Otto-Stern-Weg 1, 8093 Zurich (Switzerland); Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

    2015-05-25

    We report a method for accelerated nanoscale nuclear magnetic resonance imaging by detecting several signals in parallel. Our technique relies on phase multiplexing, where the signals from different nuclear spin ensembles are encoded in the phase of an ultrasensitive magnetic detector. We demonstrate this technique by simultaneously acquiring statistically polarized spin signals from two different nuclear species ({sup 1}H, {sup 19}F) and from up to six spatial locations in a nanowire test sample using a magnetic resonance force microscope. We obtain one-dimensional imaging resolution better than 5 nm, and subnanometer positional accuracy.

  17. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - ... into the bloodstream. The radiologist , technologist or a nurse may ask if you have allergies of any ...

  18. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... structures of the brain and can also provide functional information (fMRI) in selected cases. MR images of ... Articles and Media MR Angiography (MRA) Magnetic Resonance, Functional (fMRI) - Brain Head and Neck Cancer Treatment Brain ...

  19. Magnetic Resonance Imaging (MRI) -- Head

    Full Text Available ... Safety En Español More Info Images/Videos News Physician Resources Professions Site Index A-Z Magnetic Resonance ... allergic reaction than iodinated contrast material. Tell your doctor about any health problems, recent surgeries or allergies ...

  20. Magnetometer of nuclear magnetic resonance

    We present a nuclear magnetic resonance magnetometer that measures magnetic fields, between 2,500 gauss and 5,000 gauss, with an accuracy of a few parts per million. The circuit of the magnetometer, based on a marginal oscillator, permits a continuous tunning in the frequency range comprised between 10.0 MHz, with a signal to noise ratio of about 20. The radiofrequency amplifier is of the cascode type in integrated circuit and it operates with two 9V batteries. The modulation is at 35 Hz and it is provided by an external oscillator. The instrument is compact, inexpensive and easy to operate; it can also be used for didactic purposes to show the phenomenon of magnetic nuclear resonance and its main characteristics. (author)

  1. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    ... produced by: Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

  2. Advances in magnetic and optical resonance

    Warren, Warren S

    1997-01-01

    Since 1965, Advances in Magnetic and Optical Resonance has provided researchers with timely expositions of fundamental new developments in the theory of, experimentation with, and application of magnetic and optical resonance.

  3. Optically detected magnetic resonance imaging

    Optically detected magnetic resonance provides ultrasensitive means to detect and image a small number of electron and nuclear spins, down to the single spin level with nanoscale resolution. Despite the significant recent progress in this field, it has never been combined with the power of pulsed magnetic resonance imaging techniques. Here, we demonstrate how these two methodologies can be integrated using short pulsed magnetic field gradients to spatially encode the sample. This result in what we denote as an 'optically detected magnetic resonance imaging' technique. It offers the advantage that the image is acquired in parallel from all parts of the sample, with well-defined three-dimensional point-spread function, and without any loss of spectroscopic information. In addition, this approach may be used in the future for parallel but yet spatially selective efficient addressing and manipulation of the spins in the sample. Such capabilities are of fundamental importance in the field of quantum spin-based devices and sensors

  4. MAGNETIC RESONANCE IMAGING AND SPECTROSCOPY IN A MOUSE MODEL OF SCHIZOPHRENIA

    Torres, German; Hallas, Brian H.; Gross, Kenneth W.; Spernyak, Joseph A.; Horowitz, Judith M.

    2007-01-01

    Metabolic brain abnormalities, as demonstrated by 1H-magnetic resonance spectroscopy techniques, are common occurrences in adult schizophrenia. As mice share important biochemical and genomic similarities with humans, we tested whether brain metabolic abnormalities also occur in a transgenic mouse model of schizophrenia. In vivo 1H-magnetic resonance spectroscopy at 4.7 T of the chakragati mouse brain revealed abnormalities in relative levels of choline 3.20 ppm and N-acetylaspartate 2.01 ppm...

  5. Complete assignment of lysine resonances in 1H NMR spectra of proteins as probes of surface structure and dynamics

    A strategy is presented for complete identification of 1H spin systems of lysine residues using sophisticated 2D NMR experiments. Relayed and remote connectivities within each spin system are determined for spin subsystems based at the backbone amide and Cε proton resonances. When complete spin system identification is combined with sequence-specific assignment, protein surface structure and dynamics can be probed in a site-specific manner. The interaction between the five lysine residues of French bean plastocyanin and a model redox partner Cr(CN)63- has been examined using this approach. 12 refs.; 3 figs.; 1 table

  6. 1H, 13C, and 15N resonance assignment of the ubiquitin-like domain from Dsk2p

    Chen, Tony; Zhang, Daoning; Matiuhin, Yulia; Glickman, Michael; Fushman, David

    2008-01-01

    The ubiquitin-like domain (UBL) of yeast protein Dsk2p is widely believed to recognize and bind to ubiquitin receptors on the proteasome and, as part of Dsk2p, to bridge polyubiquitinated substrates and proteasomal degradation machinery. Here we report NMR resonance assignment for 1H, 15N, and 13C nuclei in the backbone and side chains of the UBL domain of Dsk2p. This assignment will aid in NMR studies focused on understanding of Dsk2’s interactions with proteasomal receptors and its role as ...

  7. Resonant magnetic fields from inflation

    We propose a novel scenario to generate primordial magnetic fields during inflation induced by an oscillating coupling of the electromagnetic field to the inflaton. This resonant mechanism has two key advantages over previous proposals. First of all, it generates a narrow band of magnetic fields at any required wavelength, thereby allaying the usual problem of a strongly blue spectrum and its associated backreaction. Secondly, it avoids the need for a strong coupling as the coupling is oscillating rather than growing or decaying exponentially. Despite these major advantages, we find that the backreaction is still far too large during inflation if the generated magnetic fields are required to have a strength of O(10−15 Gauss) today on observationally interesting scales. We provide a more general no-go argument, proving that this problem will apply to any model in which the magnetic fields are generated on subhorizon scales and freeze after horizon crossing

  8. Pediatric Body Magnetic Resonance Imaging.

    Kandasamy, Devasenathipathy; Goyal, Ankur; Sharma, Raju; Gupta, Arun Kumar

    2016-09-01

    Magnetic resonance imaging (MRI) is a radiation-free imaging modality with excellent contrast resolution and multiplanar capabilities. Since ionizing radiation is an important concern in the pediatric population, MRI serves as a useful alternative to computed tomography (CT) and also provides additional clues to diagnosis, not discernible on other investigations. Magnetic resonance cholangiopancreatography (MRCP), urography, angiography, enterography, dynamic multiphasic imaging and diffusion-weighted imaging provide wealth of information. The main limitations include, long scan time, need for sedation/anesthesia, cost and lack of widespread availability. With the emergence of newer sequences and variety of contrast agents, MRI has become a robust modality and may serve as a one-stop shop for both anatomical and functional information. PMID:26916887

  9. Computer Assisted Instruction (Cain) For Nuclear Magnetic Resonance Spectroscopy

    A computer assisted instruction program for nuclear magnetic resonance spectroscopy was developed by using Author ware 5.0, Adobe Image Styler 1.0, Adobe Photo shop 7.0 and Flash MX. The contents included the basic theory of 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, the instrumentation of NMR spectroscopy, the two dimensional (2D) NMR spectroscopy and the interpretation of NMR spectra. The program was also provided examples, and exercises, with emphasis on NMR spectra interpretation to determine the structure of unknown compounds and solutions for self study. The questionnaire from students showed that they were very satisfied with the software

  10. Evanescent Waves Nuclear Magnetic Resonance

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad;

    2016-01-01

    Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order to char...... a new road to a better understanding of the evanescent waves component in NMR with the opportunity to perform localized spectroscopy and imaging....

  11. Tomography by nuclear magnetic resonance

    Imaging methods based on nuclear magnetic resonance allow the production of sectional images of the human body without ionizing radiation. It is possible to measure the density and relaxation times of the water protons in body fluids or tissue. This allows not only to obtain morphological information but also to get some insight into the spatial distribution of physiological data. Starting with a review of the principles of nuclear magnetic resonance it is explained how the measured signal can be associated with an image point; it is also explained what type of apparatus is necessary and what the physical limitations are. Possible risks the patient may be exposed to in an examination using nuclear magnetic resonance are discussed. The present state of the technical development enables the production of whole-body sectional images of a living person within about one minute. By means of some typical examples the nature and properties of these images are explained. Although extensive clinical studies will be necessary before a more general assessment can be made of this method, an outlook is provided on expected further developments and possible future fields of application. (orig.)

  12. 1H, 13C, and 15N resonance assignments of murine amelogenin, an enamel biomineralization protein.

    Buchko, Garry W.; Bekhazi, Jacky G.; Cort, John R.; Valentine, Nancy B.; Snead, Malcolm L.; Shaw, Wendy J.

    2008-06-01

    Amelogenin is the predominant matrix protein in developing dental enamel. Making extensive use of residue-specific 15N-labeled amino acids samples, the majority of the main and side chain resonances for murine amelogenin were assigned in 2% aqueous acetic acid at pH 3.0. This research was performed at Pacific Northwest National Laboratory, operated by Battelle for the US-DOE. A large part of this research was performed at the W.R. Wiley Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by U.S. Department of Energy’s Office of Biological and Environmental Research (BER) program located at Pacific Northwest National Laboratory (PNNL).

  13. Magnetic Resonance Force Detection using a Membrane Resonator

    Scozzaro, Nicolas; Ruchotzke, Will; Belding, Amanda; Cardellino, Jeremy D.; Blomberg, Erick C.; McCullian, Brendan A.; Bhallamudi, Vidya P.; Pelekhov, Denis V.; Hammel, P. Chris

    2016-01-01

    The availability of compact, low-cost magnetic resonance imaging instruments would further broaden the substantial impact of this technology. We report highly sensitive detection of magnetic resonance using low-stress silicon nitride (SiN$_x$) membranes. We use these membranes as low-loss, high-frequency mechanical oscillators and find they are able to mechanically detect spin-dependent forces with high sensitivity enabling ultrasensitive magnetic resonance detection. The high force detection...

  14. Magnetic resonance spectroscopy as an imaging method

    An experimental Magnetic Resonance (MR) system with 4 tesla flux density was set up. For that purpose a data acquisition system and RF coils for resonance frequencies up to 170 MHz were developed. Methods for image guided spectroscopy as well as spectroscopic imaging focussing on the nuclei 1H and 13C were developed and tested on volunteers and selected patients. The advantages of the high field strength with respect to spectroscopic studies were demonstrated. Developments of a new fast imaging technique for the acquisition of scout images as well as a method for mapping and displaying the magnetic field inhomogeneity in-vivo represent contributions to the optimisation of the experimental procedure in spectroscopic studies. Investigations on the interaction of RF radiation with the exposed tissue allowed conclusions regarding the applicability of MR methods at high field strengths. Methods for display and processing of multi-dimensional spectroscopic imaging data sets were developed and existing methods for real-time image synthesis were extended. Results achieved in the field of computer aided analysis of MR images comprised new techniques for image background detection, contour detection and automatic image interpretation as well as knowledge bases for textural representation of medical knowledge for diagnosis. (orig.) With 82 refs., 3 tabs., 75 figs

  15. Ultra-high frequency magnetic resonance imaging

    Magill, Arthur W.

    2007-01-01

    This thesis addresses the problem of radiofrequency probe design for Ultra High Frequency Magnetic Resonance Imaging (7T). The signal-to-noise ratio available in Magnetic Resonance Imaging (MRI) is determined by the static magnetic field strength, causing a continued drive toward higher fields to enable faster image acquisition at finer spatial resolution. The resonant frequency increases linearly with static field strength. At 7T the proton resonant frequency is 300MHz, with a wavelength...

  16. Absolute hydrogen depth profiling using the resonant $^{1}$H($^{15}$N,$\\alpha\\gamma$)$^{12}$C nuclear reaction

    Reinhardt, Tobias P; Bemmerer, Daniel; Stöckel, Klaus; Wagner, Louis

    2016-01-01

    Resonant nuclear reactions are a powerful tool for the determination of the amount and profile of hydrogen in thin layers of material. Usually, this tool requires the use of a standard of well-known composition. The present work, by contrast, deals with standard-less hydrogen depth profiling. This approach requires precise nuclear data, e.g. on the widely used $^{1}$H($^{15}$N,$\\alpha\\gamma$)$^{12}$C reaction, resonant at 6.4\\,MeV $^{15}$N beam energy. Here, the strongly anisotropic angular distribution of the emitted $\\gamma$-rays from this resonance has been re-measured, resolving a previous discrepancy. Coefficients of (0.38$\\pm$0.04) and (0.80$\\pm$0.04) have been deduced for the second and fourth order Legendre polynomials, respectively. In addition, the resonance strength has been re-evaluated to (25.0$\\pm$1.5)\\,eV, 10\\% higher than previously reported. A simple working formula for the hydrogen concentration is given for cases with known $\\gamma$-ray detection efficiency. Finally, the absolute approach i...

  17. Absolute hydrogen depth profiling using the resonant 1H(15N, αγ)12C nuclear reaction

    Reinhardt, Tobias P.; Akhmadaliev, Shavkat; Bemmerer, Daniel; Stöckel, Klaus; Wagner, Louis

    2016-08-01

    Resonant nuclear reactions are a powerful tool for the determination of the amount and profile of hydrogen in thin layers of material. Usually, this tool requires the use of a standard of well-known composition. The present work, by contrast, deals with standard-less hydrogen depth profiling. This approach requires precise nuclear data, e.g. on the widely used 1 H(15 N, αγ)12 C reaction, resonant at 6.4 MeV 15 N beam energy. Here, the strongly anisotropic angular distribution of the emitted γ -rays from this resonance has been re-measured, resolving a previous discrepancy. Coefficients of (0.38 ± 0.04) and (0.80 ± 0.04) have been deduced for the second and fourth order Legendre polynomials, respectively. In addition, the resonance strength has been re-evaluated to (25.0 ± 1.5) eV, 10% higher than previously reported. A simple working formula for the hydrogen concentration is given for cases with known γ -ray detection efficiency. Finally, the absolute approach is illustrated using two examples.

  18. Magnetic resonance imaging in oncology

    Nuclear magnetic resonance (NMR) employs radio-frequency radiation in the presence of a static magnetic field to produce signals from naturally occurring nuclei in biological tissue. The information in magnetic resonance imaging (MRI) can be derived from these signals in any orthogonal plane. Hydrogen is the most abundant of such nuclei, occurring naturally in water and lipid, and can be detected at relatively low magnetic field strength (0.04 tesla (T) upwards). The MR signal from hydrogen depends not only on the proton density and the T1 and T2 relaxation times of those protons following radio-frequency pulse disturbances, but also on the timing parameters of the radio-frequency pulse sequences employed. Image contrast depends on the interaction between all these factors; not simply as in X-ray computed tomography (CT) on the properties of the tissue itself. Therefore an understanding of both the imaging process and the pathology under investigation is essential in the proper use of MRI

  19. 氢质子磁共振波谱在高苯丙氨酸血症患儿脑苯丙氨酸浓度测量的临床意义%Quantification of phenylalanine in the brain of patients with hyperphenylalaninemia by 1H magnetic resonance spectroscopy

    王琨蒂; 周忠蜀; 沈明; 洪闻; 喻唯民

    2009-01-01

    Objective Hyperphenylalaninemia (HPA) is an inborn error of metabolism in which the hydroxylation of phenylalanine (Phe) to tyrosine is disturbed. Accumulation of Phe leads to severe mental and psychomotor retardation. 1H magnetic resonance spectroscopy (1 HMRS) is a novel non-invasive method to quantitate the brain metabolites besides Phe concentration in HPA patients. And it could be acquired conveniently on clinical MRI routine scanners. This study aimed to investigate the correlation between blood Phe([Phe]blood)and [Phe]brain, the characteristics of bloed-brain Pbe metabolism and its impacts on mental retardation. Method Totally 32 untreated patients diagnosed with HPA were studied, including 18 boys and 14 girls (age ranging from 33 days to 13 years). The patients were divided into two groups: elder than 4 months old(n=22)and younger than 4 months old(n=10). 1HMRS were performed in all patients. [Phe]brain were measured by absolute [Phe]brain using Creatinine as an internal reference. [Phe]blood were measured and developmental quotient (DQ) or intelligence quotients (IQ) were evaluated. [Phe]blood was from 0.3804 to 2.5140 mmol/L (M=1.5210 mmol/L) in all the 32 cases of HPA patients. to the mental retardation (rblood=-0.5045, rbrain=-0.6471(P<0.01)) in 22 cases of the HPA patients older than 4 months. And [Phe]brain had more significant correlation with mental development than [Phe]blood. Conclusion The [Phe]blood could correspondingly represent the [Phe]brain in most HPA patients. The Phe concentration could reflect the degree of mental retadafion substantially in 22 cases with HPA older than 4 months. And the [Phe]brain could more accurately illustrate it. 1HMRS can be used to quantitate intracerebral Phe concentrations non-invasively in HPA patients. Preliminary findings suggest that interindividual variations in the kinetics of Phe uptake and metabolism do exist. 1HMRS has great clinical significance in understanding the mechanism of HPA patient's mental

  20. Nuclear magnetic resonance characterization of apple juice containing enzyme preparations

    In this work, 1H nuclear magnetic resonance (1H NMR) was employed to evaluate changes in apple juice in response to the addition of Panzym Yieldmash and Ultrazym AFP-L enzymatic complexes and compare it with premium apple juice. The juice was processed at different temperatures and concentrations of enzymatic complexes. The differences in the results were attributed mainly to the enzyme concentrations, since temperature did not cause any variation. A quantitative analysis indicated that the concentration of fructose increased while the concentrations of sucrose and glucose decreased in response to increasing concentrations of the enzymatic complexes. (author)

  1. Fast magnetization reversal of nanoclusters in resonator

    Yukalov, V. I.; Yukalova, E. P.

    2012-01-01

    An effective method for ultrafast magnetization reversal of nanoclusters is suggested. The method is based on coupling a nanocluster to a resonant electric circuit. This coupling causes the appearance of a magnetic feedback field acting on the cluster, which drastically shortens the magnetization reversal time. The influence of the resonator properties, nanocluster parameters, and external fields on the magnetization dynamics and reversal time is analyzed. The magnetization reversal time can ...

  2. Wide-range nuclear magnetic resonance detector

    Sturman, J. C.; Jirberg, R. J.

    1972-01-01

    Compact and easy to use solid state nuclear magnetic resonance detector is designed for measuring field strength to 20 teslas in cryogenically cooled magnets. Extremely low noise and high sensitivity make detector applicable to nearly all types of analytical nuclear magnetic resonance measurements and can be used in high temperature and radiation environments.

  3. Quantitative evaluation of the changes of brain metabolits in rats with focal cerebral ischemia by using 1H magnetic resonance spectrum%1H磁共振波谱对局灶性脑缺血大鼠脑内代谢物变化的定量评估

    周仁兰; 谢鹏; 罗天友; 吕发金; 牟君; 王运良

    2005-01-01

    BACKGROUND: Brain metabolic abnormality can be observed after cerebral ischemia.OBJECTIVE: To observe the changes of biochemical metabolism of rats with focal cerebral ischemia with 1H magnetic resonance spectroscopy (MRS) in order to reflect the metabolite abnormalities of rats during cerebral ischemic recovery phase.DESIGN: Randomized controlled study.SETTING: Departments of Neurology and department of Radiology of First Affiliated Hospital of Chongqing Medical University.MATERIALS: The experiment was conducted at the Radiological Department of First Affiliated Hospital of Chongqing Medical University from April to July 2004. Totally 24 adult Wistar rats with clean grade were randomly divided into three groups, namely: control group, sham operation group and cerebral ischemia group, with 8 rats in each group.METHODS: The focal cerebral ischemic model was established by occluding the right internal carotid artery in cerebral ischemia group and the filament were just inserted into the internal carotid artery not into the middle cerebral artery in sham operation group, nothing was done except for anesthetizing in the control group. 1H MRS was performed within the area of cerebral infarction and the homologous area of the contralateral hemisphere using 1.5T GE signa Highspeed MRI spectrometer in cerebral ischemic and shamed operation group at the following time point of 30 minutes, 1, 3, 6, 12, 24 hours, 3, 7, 15 days, 1 and 2 months after cerebral ischemia, and in the control group at the same time point.MAIN OUTCOME MEASURES: Changes of lactate, N-acetyl-aspartate (NAA), choline and creatine in infarct hemisphere and contralateral hemisphere.RESULTS: Totally 24 rats were selected in the study, but two died of anesthesia in sham operation group and four of serious brain edema in cerebral ischemia group, only 18 rats entered the final analysis with 8 in normal control group, 6 in sham operation group and 4 in cerebral isThe marked increase in NAA, choline and

  4. Evanescent Waves Nuclear Magnetic Resonance.

    Halidi, El Mohamed; Nativel, Eric; Akel, Mohamad; Kenouche, Samir; Coillot, Christophe; Alibert, Eric; Jabakhanji, Bilal; Schimpf, Remy; Zanca, Michel; Stein, Paul; Goze-Bac, Christophe

    2016-01-01

    Nuclear Magnetic Resonance spectroscopy and imaging can be classified as inductive techniques working in the near- to far-field regimes. We investigate an alternative capacitive detection with the use of micrometer sized probes positioned at sub wavelength distances of the sample in order to characterize and model evanescent electromagnetic fields originating from NMR phenomenon. We report that in this experimental configuration the available NMR signal is one order of magnitude larger and follows an exponential decay inversely proportional to the size of the emitters. Those investigations open a new road to a better understanding of the evanescent waves component in NMR with the opportunity to perform localized spectroscopy and imaging. PMID:26751800

  5. Hyperpolarized Renal Magnetic Resonance Imaging

    Laustsen, Christoffer

    2016-01-01

    The introduction of dissolution dynamic nuclear polarization (d-DNP) technology has enabled a new paradigm for renal imaging investigations. It allows standard magnetic resonance imaging complementary renal metabolic and functional fingerprints within seconds without the use of ionizing radiation....... Increasing evidence supports its utility in preclinical research in which the real-time interrogation of metabolic turnover can aid the physiological and pathophysiological metabolic and functional effects in ex vivo and in vivo models. The method has already been translated to humans, although the clinical...

  6. Advances in magnetic resonance 3

    Waugh, John S

    2013-01-01

    Advances in Magnetic Resonance, Volume 3, describes a number of important developments which are finding increasing application by chemists. The book contains five chapters and begins with a discussion of how the properties of random molecular rotations reflect themselves in NMR and how they show up, often differently, in other kinds of experiments. This is followed by separate chapters on the Kubo method, showing its equivalence to the Redfield approach in the cases of most general interest; the current state of dynamic nuclear polarization measurements in solutions and what they tell us abou

  7. Sequence-specific Assignment of 1H-NMR Resonance and Determination of the Secondary Structure of Jingzhaotoxin-Ⅰ

    Xiong-Zhi ZENG; Qi ZHU; Song-Ping LIANG

    2005-01-01

    Jingzhaotoxin-Ⅰ (JZTX-Ⅰ) purified from the venom of the spider Chilobrachys jingzhao is a novel neurotoxin preferentially inhibiting cardiac sodium channel inactivation by binding to receptor site 3.The structure of this toxin in aqueous solution was investigated using 2-D 1H-NMR techniques. The complete sequence-specific assignments of proton resonance in the 1H-NMR spectra of JZTX-Ⅰ were obtained by analyzing a series of 2-D spectra, including DQF-COSY, TOCSY and NOESY spectra, in H2O and D2O. All the backbone protons except for Gln4 and more than 95% of the side-chain protons were identified by dαN,dαδ, dβN and dNN connectivities in the NOESY spectrum. These studies provide a basis for the further determination of the solution conformation of JZTX-Ⅰ. Furthermore, the secondary structure of JZTX-Ⅰ was identified from NMR data. It consists mainly of a short triple-stranded antiparallel β-sheet with Trp7-Cys9, Phe20-Lys23 and Leu28-Trp31. The characteristics of the secondary structure of JZTX-Ⅰ are similar to those of huwentoxin-Ⅰ (HWTX-Ⅰ) and hainantoxin-Ⅳ (HNTX-Ⅳ), whose structures in solution have previously been reported.

  8. Tunable Magnetic Resonance in Microwave Spintronics Devices

    Chen, Yunpeng; Fan, Xin; Xie, Yunsong; Zhou, Yang; Wang, Tao; Wilson, Jeffrey D.; Simons, Rainee N.; Chui, Sui-Tat; Xiao, John Q.

    2015-01-01

    Magnetic resonance is one of the key properties of magnetic materials for the application of microwave spintronics devices. The conventional method for tuning magnetic resonance is to use an electromagnet, which provides very limited tuning range. Hence, the quest for enhancing the magnetic resonance tuning range without using an electromagnet has attracted tremendous attention. In this paper, we exploit the huge exchange coupling field between magnetic interlayers, which is on the order of 4000 Oe and also the high frequency modes of coupled oscillators to enhance the tuning range. Furthermore, we demonstrate a new scheme to control the magnetic resonance frequency. Moreover, we report a shift in the magnetic resonance frequency as high as 20 GHz in CoFe based tunable microwave spintronics devices, which is 10X higher than conventional methods.

  9. Cerebellar hemangioblastoma: magnetic resonance findings

    To characterize the results of magnetic resonance imaging in cerebellar hemangioblastoma. This retrospective study deals with seven cases of histologically-confirmed cerebellar hemangioblastoma after surgery. Another patient, diagnosed as having Von Hippel-Lindau disease, also developed this lesions, but the finding was not histologically confirmed. In all, there were 2 women and 6 men. Three of these patients presented Von Hippel-Lindaus disease. All were studied on a 0.5 T imager with T1, T2 and PD-weighted spin-echo axial planes; T1-weighted sequences were repeated after intravenous gadolinium administration. According to their aspects, the lesions were divided into three groups as follows: cyst containing a mural nodule (n=3)solid tumor (n=3) and cavitated tumor (n=1). In one patient, the lesion was initially solid and was found to present cavitation two years later. Abnormal vascularization was observed in all the tumors except for two small solid tumors, and the findings were not clear in one of the cysts containing a mural nodule. In the differential diagnosis it may be difficult to rule out other tumors, such as cystic astrocytoma. However, magnetic resonance imaging, together with the clinical data, is of diagnostic value in the three morphological types of cerebellar hemangioblastoma. (Author) 15 refs

  10. Magnetic resonance imaging of hemochromatosis arthropathy

    This study was undertaken to compare plain film radiography and magnetic resonance imaging in the assessment of hemochromatosis arthropathy of the knees of ten patients with a biopsy-proven diagnosis. Both modalities enabled visualisation of bony degenerative changes; magnetic resonance imaging enabled additional visualization of deformity of both cartilage and menisci. Magnetic resonance imaging failed reliably to confirm the presence of intra-articular iron in the patients studied. No correlation was observed between synovial fluid magnetic resonance signal values, corresponding serum ferritin levels, or the severity of the observed degenerative changes. (orig.)

  11. Society for Cardiovascular Magnetic Resonance guidelines for reporting cardiovascular magnetic resonance examinations

    van Rossum Albert C; Raman Subha V; McConnell Michael V; Lawson Mark A; Higgins Charles B; Friedrich Matthias G; Bogaert Jan G; Bluemke David; Hundley W Gregory; Flamm Scott; Kramer Christopher M; Nagel Eike; Neubauer Stefan

    2009-01-01

    Abstract These reporting guidelines are recommended by the Society for Cardiovascular Magnetic Resonance (SCMR) to provide a framework for healthcare delivery systems to disseminate cardiac and vascular imaging findings related to the performance of cardiovascular magnetic resonance (CMR) examinations.

  12. Nuclear Magnetic Resonance Imaging of Li-ion Battery

    D. Ohno

    2010-12-01

    Full Text Available Nuclear magnetic resonance (NMR imaging has high sensitivity to proton (1H and lithium (7Li. It is a useful measurement for electrolyte in Li-ion battery. 1H NMR images of lithium ion battery which is composed of LiMn2O4 / LiClO4 + propylene carbonate (PC / Li-metal have been studied. 1H NMR images of electrolyte near cathode material (LiMn2O4 showed anomalous intensity distribution, which was quite inhomogeneous. From NMR images as a function of repetition time (TR, it was concluded that the anomalous intensity distribution was not due to change of relaxation time but an indirect (spatial para-magnetization effect from cathode material. The paramagnetization induced by high magnetic field distorts linearity of magnetic gradient field, leading to apparent intensity variance. This functional image is an easy diagnostic measurement for magnetization of cathode material, which allows the possibility to check uniformity of cathode material and change of magnetization under electrochemical process.

  13. Fetal abdominal magnetic resonance imaging

    This review deals with the in vivo magnetic resonance imaging (MRI) appearance of the human fetal abdomen. Imaging findings are correlated with current knowledge of human fetal anatomy and physiology, which are crucial to understand and interpret fetal abdominal MRI scans. As fetal MRI covers a period of more than 20 weeks, which is characterized not only by organ growth, but also by changes and maturation of organ function, a different MR appearance of the fetal abdomen results. This not only applies to the fetal intestines, but also to the fetal liver, spleen, and adrenal glands. Choosing the appropriate sequences, various aspects of age-related and organ-specific function can be visualized with fetal MRI, as these are mirrored by changes in signal intensities. Knowledge of normal development is essential to delineate normal from pathological findings in the respective developmental stages

  14. Magnetic Resonance Imaging of Electrolysis.

    Meir, Arie; Hjouj, Mohammad; Rubinsky, Liel; Rubinsky, Boris

    2015-02-01

    This study explores the hypothesis that Magnetic Resonance Imaging (MRI) can image the process of electrolysis by detecting pH fronts. The study has relevance to real time control of cell ablation with electrolysis. To investigate the hypothesis we compare the following MR imaging sequences: T1 weighted, T2 weighted and Proton Density (PD), with optical images acquired using pH-sensitive dyes embedded in a physiological saline agar solution phantom treated with electrolysis and discrete measurements with a pH microprobe. We further demonstrate the biological relevance of our work using a bacterial E. Coli model, grown on the phantom. The results demonstrate the ability of MRI to image electrolysis produced pH changes in a physiological saline phantom and show that these changes correlate with cell death in the E. Coli model grown on the phantom. The results are promising and invite further experimental research.

  15. Magnetic Resonance Imaging of Neurosarcoidosis

    Daniel T Ginat

    2011-01-01

    Full Text Available Neurosarcoidosis is an uncommon condition with protean manifestations. Magnetic resonance imaging (MRI is often used in the diagnostic evaluation and follow-up of patients with neurosarcoidosis. Therefore, familiarity with the variety of MRI appearances is important. In this pictorial essay, the range of possible patterns of involvement in neurosarcoidosis are depicted and discussed. These include intracranial and spine leptomeningeal involvement, cortical and cerebral white matter lesions, corpus callosum involvement, sellar and suprasellar involvement, periventricular involvement, cranial nerve involvement, cavernous sinus involvement, hydrocephalus, dural involvement, ischemic lesions, perivascular involvement, orbit lesions, osseous involvement, nerve root involvement, and spinal cord intramedullary involvement. Differential diagnoses for each pattern of involvement of neurosarcoidosis are also provided.

  16. Synovial pathology: Magnetic resonance study

    The synovial membrane lines the inner surface of the entire joint capsule of the so-called synovial, or diarthrosis, joints. It also constitutes the lining synovial bursa and tendon sheaths. It is lubricated at all these sites by the synovial fluid secreted by the membrane itself. The identification of this structure is bases on the correct knowledge of its anatomical locations. Synovial membrane pathology includes lesions produced by tumors, inflammation, degeneration and trauma. In this report, we classify them as benign (cysts, chondromatosis, pigmented villonodular synovitis, inflammatory synovitis and hemangioma) or malignant (synovial sarcoma and hemangiosarcoma). Magnetic resonance (MR) constitutes a useful and reliable method for diagnosis synovial lesions, providing a means of determining their origin and identifying distinctive features of some types. We present our experience in 12 cases of synovial pathology studied by MR over the past year, all of which were confirmed by histopathological study. 13 refs

  17. Fetal abdominal magnetic resonance imaging

    Brugger, Peter C. [Center of Anatomy and Cell Biology, Integrative Morphology Group, Medical University of Vienna, Waehringerstrasse 13, 1090 Vienna (Austria)]. E-mail: peter.brugger@meduniwien.ac.at; Prayer, Daniela [Department of Radiology, Medical University of Vienna, Waehringerguertel 18-20, 1090 Vienna (Austria)

    2006-02-15

    This review deals with the in vivo magnetic resonance imaging (MRI) appearance of the human fetal abdomen. Imaging findings are correlated with current knowledge of human fetal anatomy and physiology, which are crucial to understand and interpret fetal abdominal MRI scans. As fetal MRI covers a period of more than 20 weeks, which is characterized not only by organ growth, but also by changes and maturation of organ function, a different MR appearance of the fetal abdomen results. This not only applies to the fetal intestines, but also to the fetal liver, spleen, and adrenal glands. Choosing the appropriate sequences, various aspects of age-related and organ-specific function can be visualized with fetal MRI, as these are mirrored by changes in signal intensities. Knowledge of normal development is essential to delineate normal from pathological findings in the respective developmental stages.

  18. High-field small animal magnetic resonance oncology studies

    Bokacheva, Louisa; Ackerstaff, Ellen; LeKaye, H. Carl; Zakian, Kristen; Koutcher, Jason A.

    2014-01-01

    This review focuses on the applications of high magnetic field magnetic resonance imaging (MRI) and spectroscopy (MRS) to cancer studies in small animals. High-field MRI can provide information about tumor physiology, the microenvironment, metabolism, vascularity and cellularity. Such studies are invaluable for understanding tumor growth and proliferation, response to treatment and drug development. The MR techniques reviewed here include 1H, 31P, chemical exchange saturation transfer imaging and hyperpolarized 13C MRS as well as diffusion-weighted, blood oxygen level dependent contrast imaging and dynamic contrast-enhanced MRI. These methods have been proven effective in animal studies and are highly relevant to human clinical studies.

  19. Contrast agents in magnetic resonance imaging

    The origine of nuclear magnetic resonance signal is reminded and different ways for contrast enhancement in magnetic resonance imaging are presented, especially, modifications of tissus relaxation times. Investigations have focused on development of agents incorporating either paramagnetic ions or stable free radicals. Pharmacological and toxicological aspects are developed. The diagnostic potential of these substances is illustrated by the example of gadolinium complexes

  20. Pituitary tumors: Diagnosis by magnetic resonance imaging

    This paper presents a survey of the current status of the diagnosis of pituitary tumors by means of magnetic resonance imaging. It focuses on the clinical and practical aspects. The recommended procedure and the sequences and slice orientations for magnetic resonance imaging of the pituitary gland are presented, and the features that are essential for the diagnosis of pituitary tumors are discussed. (orig.)

  1. Magnetic resonance force microscopy: recent results

    Force detection of magnetic resonance has been demonstrated experimentally and used for imaging in EPR. This paper will review the basic principles of Magnetic Resonance Force Microscopy (MRFM) and will report some recent results in NMR imaging and the operation of a low-temperature MRFM. (author). 31 refs., 14 figs

  2. Nuclear magnetic resonance studies of erythrocyte membranes

    Chapman, D.; Kamat, V.B.; Gier, J. de; Penkett, S.A.

    1968-01-01

    The use of nuclear magnetic resonance spectroscopy for studying molecular interactions in biological membranes has been investigated using erythrocyte membrane fragments. Sonic dispersion of these fragments produces a sharp and well-defined high-resolution nuclear magnetic resonance spectrum. The sp

  3. Chemical Principles Revisited. Proton Magnetic Resonance Spectroscopy.

    McQuarrie, Donald A.

    1988-01-01

    Discusses how to interpret nuclear magnetic resonance (NMR) spectra and how to use them to determine molecular structures. This discussion is limited to spectra that are a result of observation of only the protons in a molecule. This type is called proton magnetic resonance (PMR) spectra. (CW)

  4. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Full Text Available ... produced by: Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot ... I’d like to talk with you about magnetic resonance angiography, or as it’s commonly known, MRA. MRA ...

  5. Magnetic resonance imaging of the prostate

    Iversen, P; Kjaer, L; Thomsen, C;

    1987-01-01

    Magnetic resonance imaging offers new possibilities in the investigation of the prostate. The current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be of value in the staging of carcinoma of the prostate....

  6. Magnetic resonance imaging of the prostate

    Iversen, P; Kjaer, L; Thomsen, C;

    1988-01-01

    Magnetic resonance imaging offers new possibilities in investigation of the prostate gland. Current results of imaging and tissue discrimination in the evaluation of prostatic disease are reviewed. Magnetic resonance imaging may be useful in the staging of carcinoma of the prostate....

  7. Functional Magnetic Resonance Imaging and Pediatric Anxiety

    Pine, Daniel S.; Guyer, Amanda E.; Leibenluft, Ellen; Peterson, Bradley S.; Gerber, Andrew

    2008-01-01

    The use of functional magnetic resonance imaging in investigating pediatric anxiety disorders is studied. Functional magnetic resonance imaging can be utilized in demonstrating parallels between the neural architecture of difference in anxiety of humans and the neural architecture of attention-orienting behavior in nonhuman primates or rodents.…

  8. Magnetic non-collinear neutron wave resonator

    Khaidukov, Yu N

    2009-01-01

    The expression are received for amplitude of neutron reflection from layered magnetic non-collinear structure (neutron wave resonator (NWR)). It is showed the magnetic non-collinear NWR is characterized by the system of pairs of resonances for the spin flipped neutrons. The conditions are defined at which amplifying of spin-flipped neutron flux in wave resonator is multiple increased in comparison with amplifying of neutron absorption.

  9. Magnetic Resonance of the Knee

    Magnetic Resonance Imaging (MRI) has been applied to muscoloskeletal pathoanatomy and has proved to be useful in the detection and characterization of knees and 8 normal knees were examined. The images were obtained in the Diagnostic Centre RMRC of Naples on a 0.5 T superconductive magnetic system, using a surface coil and a spin-echo pulse sequence (SE 600/28 ms). The examined limb was immobilized and bent at 8-10 grade, extrarotated for the examination of the anterior cruciate ligament (ACL) only. Images were obtained on a 256x256 matrix and had a 2 or 4-mm thickness. MRI cleary showed all the anatomical structures. The anterior and posterior cruciate ligaments (ACL and PAL) and tha patellar ligament were shown by sagittal SE images through the intercondylar notch; the tibial and fibular collateral ligaments (TCL and FCL) were evaluated on coronal SE images; the articular capsula and menisci on axial transverse SE images. Objective criteria for ACL and PCL tears were: lack of continuity of the signal and change in signal intensity; in meniscal pathology, menisci with small linear regions of increased signal or with grossly truncated shape were interpreted as tears. Preliminary results of this study indicate that MRI together with clinical evaluation may be an useful non-invasive procedure in the assessment of acute injuries of the knee

  10. Stepped Impedance Resonators for High Field Magnetic Resonance Imaging

    Akgun, Can E.; DelaBarre, Lance; Yoo, Hyoungsuk; Sohn, Sung-Min; Snyder, Carl J.; Adriany, Gregor; Ugurbil, Kamil; Gopinath, Anand; Vaughan, J. Thomas

    2014-01-01

    Multi-element volume radio-frequency (RF) coils are an integral aspect of the growing field of high field magnetic resonance imaging (MRI). In these systems, a popular volume coil of choice has become the transverse electromagnetic (TEM) multi-element transceiver coil consisting of microstrip resonators. In this paper, to further advance this design approach, a new microstrip resonator strategy in which the transmission line is segmented into alternating impedance sections referred to as step...

  11. Magnetic Microparticle Aggregation For Viscosity Determination By Magnetic Resonance

    Hong, Rui; Cima, Michael J; Weissleder, Ralph; Josephson, Lee

    2008-01-01

    Micron-sized magnetic particles were induced to aggregate when placed in homogeneous magnetic fields, like those of magnetic resonance (MR) imagers and relaxometers, and then spontaneously returned to their dispersed state when removed from the field. Associated with the aggregation and dispersion of the magnetic particles were time dependent increases and decreases in the spin-spin relaxation time (T2) of the water. Magnetic nanoparticles, with far smaller magnetic moments per particle, did ...

  12. Nuclear Magnetic Resonance imaging; Resonance magnetique nucleaire

    Thibierge, M.; Sevestre, L.; Slupecki, P. [Centre Hospitalier de Charleville-Mezieres, 08 (France)

    1998-06-01

    After many years of low profile business in the USA, MRI is back. Improvements are focused on high field magnets and on low field magnets. The former, are dedicated to high quality imaging. The new scanners are more and more efficient because of the spreading use of real time imaging. They can do now, procedures that just could not be imagined some years ago. Vascular imaging is done routinely. Abdominal imaging in apnea of EPI, perfusion and diffusion imaging, and, last not least, all the field of functional imaging are on the verge of coming out. The new magnets unveiled in 1997 are lighter, smaller, more, user friendly, less impressive for patients subject to claustrophobia. They also need less helium to operate and less space to be sited. The latter, are dedicated to interventional procedures. The new magnets are wide opened and a lot of companies show off. Though Picker unveiled a new light superconductive 0.5 Tesla magnet, it seems that this kind of machines are about to disappear. No significant progress was noticed in the field of dedicated MRI devices. Some features can be highlighted: the new Siemens short bore and its table integrates the Panoramic Array Coil Concept. It will allow simultaneous scanning with up to four coils; the excellent homogeneity of the new Picker magnet that will allow spectroscopy at 1 Tesla; the twin gradients of the Elscint Prisma that will open the field of microscopy MRI; the Philips `floppy gradients` that could speed up 4 or 6 times, the time needed for imaging; some new sequences sensitive to temperature are studied as WIP; a lot of work is achieved on 3 or 4 Tesla scanners etc. (author)

  13. Magnetic resonance imaging in mucopolysaccharidosis

    Nakajima, Seijun; Tanaka, Akemi; Kawawaki, Hisashi; Hattori, Hideji; Matsuoka, Osamu; Murata, Ryosuke; Isshiki, Gen; Inoue, Yuichi

    1988-11-01

    Magnetic resonance (MR) images in six patients with mucopolysaccharidosis (MPS), two with type I S, one with type II A, two with type III B, and one with type VI MPS, were reviewed and compared with reported pathological findings and with CT scans. We used a Picker International MR imager with a 0.5-tesla superconducting magnet. The pulse sequences involved the inversion recovery technique (TR, 2,100 msec ; TI, 600 msec ; TE, 40 msec) for the T/sub 1/-weighted images and spin echo technique (TR, 1,800 msec ; TE, 120 msec) for the T/sub 2/-weighted images. The TC scanner was a Somatom 2 or DR3. In the patients with type II A and type VI MPS, there were multi-focal lesions of various sizes that showed prolonged T/sub 1/ and T/sub 2/ in the white matter. These lesions, which were not detected by CT, seemed to be correlated with the pathological findings of cavitation and dilated periadventitial space with viscous fluid. In the patients with type II A and type III B MPS, the T/sub 2/-weighted images showed a reduced contrast between gray and white matters, which may be related to the deposition of glycolipids and mucopolysaccharides in the lysosomes of the neurons and astrocytes of the gray and white matters. These findings seemed to be correlated with the clinical finding of mental retardation. In the patient of type II A MPS, there were lesions that showed prolonged T/sub 2/ of the periventricular white matter, suggesting periventricular edema. But CT hardly detected these lesions. In the patients with type I S MPS, no abnormal findings were found in MR imaging. It was concluded that MR imaging was far more sensitive for the detection of MPS lesions than CT, and was a useful method for differential diagnosis in MPS.

  14. Magnetic resonance imaging in mucopolysaccharidosis

    Magnetic resonance (MR) images in six patients with mucopolysaccharidosis (MPS), two with type I S, one with type II A, two with type III B, and one with type VI MPS, were reviewed and compared with reported pathological findings and with CT scans. We used a Picker International MR imager with a 0.5-tesla superconducting magnet. The pulse sequences involved the inversion recovery technique (TR, 2,100 msec ; TI, 600 msec ; TE, 40 msec) for the T1-weighted images and spin echo technique (TR, 1,800 msec ; TE, 120 msec) for the T2-weighted images. The TC scanner was a Somatom 2 or DR3. In the patients with type II A and type VI MPS, there were multi-focal lesions of various sizes that showed prolonged T1 and T2 in the white matter. These lesions, which were not detected by CT, seemed to be correlated with the pathological findings of cavitation and dilated periadventitial space with viscous fluid. In the patients with type II A and type III B MPS, the T2-weighted images showed a reduced contrast between gray and white matters, which may be related to the deposition of glycolipids and mucopolysaccharides in the lysosomes of the neurons and astrocytes of the gray and white matters. These findings seemed to be correlated with the clinical finding of mental retardation. In the patient of type II A MPS, there were lesions that showed prolonged T2 of the periventricular white matter, suggesting periventricular edema. But CT hardly detected these lesions. In the patients with type I S MPS, no abnormal findings were found in MR imaging. It was concluded that MR imaging was far more sensitive for the detection of MPS lesions than CT, and was a useful method for differential diagnosis in MPS. (author)

  15. Artifacts in Magnetic Resonance Imaging

    Artifacts in magnetic resonance imaging and foreign bodies within the patient’s body may be confused with a pathology or may reduce the quality of examinations. Radiologists are frequently not informed about the medical history of patients and face postoperative/other images they are not familiar with. A gallery of such images was presented in this manuscript. A truncation artifact in the spinal cord could be misinterpreted as a syrinx. Motion artifacts caused by breathing, cardiac movement, CSF pulsation/blood flow create a ghost artifact which can be reduced by patient immobilization, or cardiac/respiratory gating. Aliasing artifacts can be eliminated by increasing the field of view. An artificially hyperintense signal on FLAIR images can result from magnetic susceptibility artifacts, CSF/vascular pulsation, motion, but can also be found in patients undergoing MRI examinations while receiving supplemental oxygen. Metallic and other foreign bodies which may be found on and in patients’ bodies are the main group of artifacts and these are the focus of this study: e.g. make-up, tattoos, hairbands, clothes, endovascular embolization, prostheses, surgical clips, intraorbital and other medical implants, etc. Knowledge of different types of artifacts and their origin, and of possible foreign bodies is necessary to eliminate them or to reduce their negative influence on MR images by adjusting acquisition parameters. It is also necessary to take them into consideration when interpreting the images. Some proposals of reducing artifacts have been mentioned. Describing in detail the procedures to avoid or limit the artifacts would go beyond the scope of this paper but technical ways to reduce them can be found in the cited literature

  16. Interaction of magnetic resonators studied by the magnetic field enhancement

    Yumin Hou

    2013-01-01

    It is the first time that the magnetic field enhancement (MFE) is used to study the interaction of magnetic resonators (MRs), which is more sensitive than previous parameters–shift and damping of resonance frequency. To avoid the coherence of lattice and the effect of Bloch wave, the interaction is simulated between two MRs with same primary phase when the distance is changed in the range of several resonance wavelengths, which is also compared with periodic structure. The calculated MFE osci...

  17. Functional magnetic resonance imaging by visual stimulation

    We evaluated functional magnetic resonance images obtained in 8 healthy subjects in response to visual stimulation using a conventional clinical magnetic resonance imaging system with multi-slice spin-echo echo planar imaging. Activation in the visual cortex was clearly demonstrated by the multi-slice experiment with a task-related change in signal intensity. In addition to the primary visual cortex, other areas were also activated by a complicated visual task. Multi-slice spin-echo echo planar imaging offers high temporal resolution and allows the three-dimensional analysis of brain function. Functional magnetic resonance imaging provides a useful noninvasive method of mapping brain function. (author)

  18. Presurgical functional magnetic resonance imaging

    Functional magnetic resonance imaging (fMRI) is an important and novel neuroimaging modality for patients with brain tumors. By non-invasive measurement, localization and lateralization of brain activiation, most importantly of motor and speech function, fMRI facilitates the selection of the most appropriate and sparing treatment and function-preserving surgery. Prerequisites for the diagnostic use of fMRI are the application of dedicated clinical imaging protocols and standardization of the respective imaging procedures. The combination with diffusion tensor imaging (DTI) also enables tracking and visualization of important fiber bundles such as the pyramidal tract and the arcuate fascicle. These multimodal MR data can be implemented in computer systems for functional neuronavigation or radiation treatment. The practicability, accuracy and reliability of presurgical fMRI have been validated by large numbers of published data. However, fMRI cannot be considered as a fully established modality of diagnostic neuroimaging due to the lack of guidelines of the responsible medical associations as well as the lack of medical certification of important hardware and software components. This article reviews the current research in the field and provides practical information relevant for presurgical fMRI. (orig.)

  19. Magnetic resonance in multiple sclerosis

    Magnetic Resonance Imaging was performed in more than 200 patients with clinical suspicion or knowledge of Multiple Sclerosis. One hundred and forty-seven (60 males and 87 females) had MR evidence of multiple sclerosis lesions. The MR signal of demyelinating plaques characteristically has prolonged T1 and T2 relaxation times and the T2-weighted spin-echo sequences are generally superior to the T1-weighted images because the lesions are better visualized as areas of increased signal intensity. MR is also able to detect plaques in the brainstem, cerebellum and within the cervical spinal cord. MR appears to be an important, non-invasive method for the diagnosis of Multiple Sclerosis and has proven to be diagnostically superior to CT, evoked potentials (EP) and CSF examination. In a selected group of 30 patients, with the whole battery of the relevant MS studies, MR was positive in 100%, CT in 33,3%, EP in 56% and CSF examination in 60%. In patients clinically presenting only with signs of spinal cord involvement or optic neuritis or when the clinical presentation is uncertain MR has proven to be a very useful diagnostic tool for diagnosis of MS by demonstrating unsuspected lesions in the cerebral hemispheres. (orig.)

  20. Magnetic resonance spectroscopy in schizophrenia. Possibilities and limitations

    Magnetic resonance spectroscopy is a noninvasive investigative technique for in vivo detection of biochemical changes in neuropsychiatric disorders for which especially proton (1H-MRS) and phosphorus (31P-MRS) magnetic resonance spectroscopy have been used. In this review we explain the principles of MRS and summarize the studies in schizophrenia. A systematic literature review was carried out for 1H-MRS studies investigating schizophrenic patients compared to controls. The inconsistent results in the cited studies may be due to different study population, specific neuroimaging technique, and selected brain regions. Frequent findings are decreased PME and increased PDE concentrations (31P-MRS) linked to altered metabolism of membrane phospholipids and decreased N-acetylaspartate (NAA) or NAA/choline ratio (1H-MRS) linked to neuronal damage in frontal (DLPFC) or temporal regions in patients with schizophrenia. These results contribute to the disturbed frontotemporal-thalamic network assumed in schizophrenia and are supported by additional functional neuroimaging, MRI morphometry, and neuropsychological evaluation. The combination of the described investigative techniques with MRS in follow-up studies may provide more specific clues for understanding the pathogenesis and disease course in schizophrenia. (orig.)

  1. A Magnetic Resonance Measurement Technique for Rapidly Switched Gradient Magnetic Fields in a Magnetic Resonance Tomograph

    K. Bartušek

    2003-01-01

    Full Text Available This paper describes a method for measuring of the gradient magnetic field in Nuclear Magnetic Resonance (NMR tomography, which is one of the modern medical diagnostic methods. A very important prerequisite for high quality imaging is a gradient magnetic field in the instrument with exactly defined properties. Nuclear magnetic resonance enables us to measure the pulse gradient magnetic field characteristics with high accuracy. These interesting precise methods were designed, realised, and tested at the Institute of Scientific Instruments (ISI of the Academy of Sciences of the Czech Republic. The first of them was the Instantaneous Frequency (IF method, which was developed into the Instantaneous Frequency of Spin Echo (IFSE and the Instantaneous Frequency of Spin Echo Series (IFSES methods. The above named methods are described in this paper and their a comparison is also presented.

  2. Enhancement of artificial magnetism via resonant bianisotropy

    Markovich, Dmitry; Baryshnikova, Kseniia; Shalin, Alexander; Samusev, Anton; Krasnok, Alexander; Belov, Pavel; Ginzburg, Pavel

    2016-03-01

    All-dielectric “magnetic light” nanophotonics based on high refractive index nanoparticles allows controlling magnetic component of light at nanoscale without having high dissipative losses. The artificial magnetic optical response of such nanoparticles originates from circular displacement currents excited inside those structures and strongly depends on geometry and dispersion of optical materials. Here an approach for enhancing of magnetic response via resonant bianisotropy effect is proposed and analyzed. The key mechanism of enhancement is based on electric-magnetic interaction between two electrically and magnetically resonant nanoparticles of all-dielectric dimer. It was shown that proper geometrical arrangement of the dimer in respect to the incident illumination direction allows flexible control over all vectorial components of the magnetic moment, tailoring the latter in the dynamical range of 100% and delivering enhancement up to 36% relative to performances of standalone spherical particles. The proposed approach provides pathways for designs of all-dielectric metamaterials and metasurfaces with strong magnetic responses.

  3. Magnetic resonance imaging study on rat sugar cataract

    Proton nuclear magnetic resonance (1H-NMR) is one of the most important methods for noninvasively evaluating the state of water in the biological system. It could be useful for evaluation of the early changes of cataract. In this study, in vivo magnetic resonance imaging (MRI) was applied to rat galactosemic cataract, which is a model of the human diabetic cataract, and compared with the histological findings. The relationship between the relaxation times (T1, T2) and the water contents were discussed. The T1 and T2 values were prolonged and the high intensity area of the lens cortex was enlarged from the early stage of the cataract (two days after the intake of galactose). These changes preceded the histological changes. This suggests that MRI is applicable for the evaluation of anti-cataract agents, for example aldose reductase inhibitors, against human diabetic cataract. (author)

  4. Reducing Field Distortion in Magnetic Resonance Imaging

    Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob

    2010-01-01

    A concept for a magnetic resonance imaging (MRI) system that would utilize a relatively weak magnetic field provides for several design features that differ significantly from the corresponding features of conventional MRI systems. Notable among these features are a magnetic-field configuration that reduces (relative to the conventional configuration) distortion and blurring of the image, the use of a superconducting quantum interference device (SQUID) magnetometer as the detector, and an imaging procedure suited for the unconventional field configuration and sensor. In a typical application of MRI, a radio-frequency pulse is used to excite precession of the magnetic moments of protons in an applied magnetic field, and the decaying precession is detected for a short time following the pulse. The precession occurs at a resonance frequency proportional to the strengths of the magnetic field and the proton magnetic moment. The magnetic field is configured to vary with position in a known way; hence, by virtue of the aforesaid proportionality, the resonance frequency varies with position in a known way. In other words, position is encoded as resonance frequency. MRI using magnetic fields weaker than those of conventional MRI offers several advantages, including cheaper and smaller equipment, greater compatibility with metallic objects, and higher image quality because of low susceptibility distortion and enhanced spin-lattice-relaxation- time contrast. SQUID MRI is being developed into a practical MRI method for applied magnetic flux densities of the order of only 100 T

  5. High Resolution Magic Angle Spinning 1H-NMR Metabolic Profiling of Nanoliter Biological Tissues at High Magnetic Field

    Feng, Ju; Hu, Jian Z.; Burton, Sarah D.; Hoyt, David W.

    2013-03-05

    It is demonstrated that a high resolution magic angle spinning 1H-NMR spectrum of biological tissue samples with volumes as small as 150 nanoliters, or 0.15 mg in weight, can be acquired in a few minutes at 21.1 T magnetic field using a commercial 1.6 mm fast-MAS probe with minor modification of the MAS rotor. The strategies of sealing the samples inside the MAS rotor to avoid fluid leakage as well as the ways of optimizing the signal to noise are discussed.

  6. Quantifying mixing using magnetic resonance imaging.

    Tozzi, Emilio J; McCarthy, Kathryn L; Bacca, Lori A; Hartt, William H; McCarthy, Michael J

    2012-01-01

    Mixing is a unit operation that combines two or more components into a homogeneous mixture. This work involves mixing two viscous liquid streams using an in-line static mixer. The mixer is a split-and-recombine design that employs shear and extensional flow to increase the interfacial contact between the components. A prototype split-and-recombine (SAR) mixer was constructed by aligning a series of thin laser-cut Poly (methyl methacrylate) (PMMA) plates held in place in a PVC pipe. Mixing in this device is illustrated in the photograph in Fig. 1. Red dye was added to a portion of the test fluid and used as the minor component being mixed into the major (undyed) component. At the inlet of the mixer, the injected layer of tracer fluid is split into two layers as it flows through the mixing section. On each subsequent mixing section, the number of horizontal layers is duplicated. Ultimately, the single stream of dye is uniformly dispersed throughout the cross section of the device. Using a non-Newtonian test fluid of 0.2% Carbopol and a doped tracer fluid of similar composition, mixing in the unit is visualized using magnetic resonance imaging (MRI). MRI is a very powerful experimental probe of molecular chemical and physical environment as well as sample structure on the length scales from microns to centimeters. This sensitivity has resulted in broad application of these techniques to characterize physical, chemical and/or biological properties of materials ranging from humans to foods to porous media (1, 2). The equipment and conditions used here are suitable for imaging liquids containing substantial amounts of NMR mobile (1)H such as ordinary water and organic liquids including oils. Traditionally MRI has utilized super conducting magnets which are not suitable for industrial environments and not portable within a laboratory (Fig. 2). Recent advances in magnet technology have permitted the construction of large volume industrially compatible magnets suitable for

  7. Biliary Ascariasis on Magnetic Resonance Cholangiopancreatography

    Hashmi, Mohammad A; Jevan K De

    2009-01-01

    A 17-year-old girl presented with features of biliary obstruction. Magnetic resonance cholangi-pancreatography revealed typical linear signals in common bile duct, which appears like Ascaris lumbricoides. The diagnosis was confirmed by endoscopic removal of the worm.

  8. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Full Text Available ... this Site RadiologyInfo.org is produced by: Image/Video Gallery Your Radiologist Explains Magnetic Resonance Angiography (MRA) ... Recently posted: Focused Ultrasound for Uterine Fibroids Dementia Video: General Ultrasound Video: Pediatric Nuclear Medicine Radiology and ...

  9. Your Radiologist Explains Magnetic Resonance Angiography (MRA)

    Full Text Available ... Pediatric Ultrasound Video: Angioplasty & vascular stenting Video: Arthrography Radiology and You About this Site RadiologyInfo.org is ... Explains Magnetic Resonance Angiography (MRA) Transcript Welcome to Radiology Info dot org Hello, I’m Dr. Elliot ...

  10. Chronic liver disease: evaluation by magnetic resonance

    Magnetic resonance (MR) imaging distinguished hepatitis from fatty liver and cirrhosis in a woman with a history of alcohol abuse. Anatomic and physiologic manifestations of portal hypertension were also demonstrated by MR