• Title/Summary/Keyword: Proton magnetic resonance spectroscopy

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[ $^1H$ ] Magnetic Resonance Spectroscopy of Primary Central Nervous System Lymphoma (일차성 중추신경 림프종의 수소 자기공명분광법)

  • Kim Yong Sun;Lee Hui Joong
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.2
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    • pp.86-93
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    • 2004
  • Purpose: We evaluated $^1H$ MR spectroscopy improves the preoperative diagnosis of diffuse infiltrative type of primary central nervous system lymphomas. Materials and methods: After review of conventional MR images and medical records, we retrospectively reviewed proton MR spectra in seven patients with primary central nervous system lymphoma diagnosed by means of biopsy. Relative ratio of choline (Cho), N-acetylaspartate (NAA), and lipid-lactate (Lip-Lac) to creatine (Cr) were measured for quantitative analysis. Results: The average ratio of Cho/Cr was $1.80{\pm}0.95$, NAA/Cr was $1.34{\pm}0.41$, and Lip-Lac/Cr was $1.12{\pm}0.16$. All cases of lymphomas showed increased Lip-Lac peak. Two case of mass forming lymphoma showed decreased NAA/Cr significantly, whereas five cases of lymphoma without mass formation showed preserved NAA/Cr. Conclusion : We thought the presence of Lip-Lac peak without significant reduction of NAA on the MR spectroscopy was helpful for diagnosis of diffuse infiltrative type of central nervous system lymphoma.

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Conformational Study of Decamer DNA Duplex $d(ACGTATACGT)_2$ by NMR Spectroscopy

  • Lee, Joon-Hwa;Park, Jin-Young;Han, Hi-Jung;Park, Byong-Seok
    • Journal of the Korean Magnetic Resonance Society
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    • v.1 no.2
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    • pp.63-70
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    • 1997
  • The conformation of the self-complementary decamer duplex, d(ACGTATACGT)2 (TATA-duplex) has been studied by proton NMR spectroscopy. The duplex is essentially B-type, with distortions apparent at the TATA steps. These conformational distortion which may be preferable to occur in the thymine residue on the 5'-side, has been investigated by unusual NOE crosspeaks.

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Assessment of Malignancy in Brain Tumors by 3T MR Spectroscopy

  • 최보영;전신수;김범수;이재문;정성택;안창범;오창현;김선일;이형구
    • Proceedings of the KSMRM Conference
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    • 2003.10a
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    • pp.84-84
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    • 2003
  • Purpose: To assess clinical proton MR spectroscopy (MRS) as a noninvasive method for evaluating tumor malignancy at 3T high field system. Materials and methods: Using 3T MRI/MRS system, localized water-suppressed single-voxel technique in patients with brain tumors was employed to evaluate spectra with peaks of N-acetyl aspartate (NAA), choline-containing compounds (Cho), creatine/phosphocreatine (Cr) and lactate. On the basis of Cr, these peak areas were quantificated as a relative ratio.

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1D Proton NMR Spectroscopic Determination of Ethanol and Ethyl Glucuronide in Human Urine

  • Kim, Siwon;Lee, Minji;Yoon, Dahye;Lee, Dong-Kye;Choi, Hye-Jin;Kim, Suhkmann
    • Bulletin of the Korean Chemical Society
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    • v.34 no.8
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    • pp.2413-2418
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    • 2013
  • Forensic and legal medicine require reliable data to indicate excessive alcohol consumption. Ethanol is oxidatively metabolized to acetate by alcohol dehydrogenase and non-oxidatively metabolized to ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanol, or fatty acid ethyl esters (FAEE). Oxidative metabolism is too rapid to provide biomarkers for the detection of ethanol ingestion. However, the non-oxidative metabolite EtG is a useful biomarker because it is stable, non-volatile, water soluble, highly sensitive, and is detected in body fluid, hair, and tissues. EtG analysis methods such as mass spectroscopy, chromatography, or enzyme-linked immunosorbent assay techniques are currently in use. We suggest that nuclear magnetic resonance (NMR) spectroscopy could be used to monitor ethanol intake. As with current conventional methods, NMR spectroscopy doesn't require complicated pretreatments or sample separation. This method has the advantages of short acquisition time, simple sample preparation, reproducibility, and accuracy. In addition, all proton-containing compounds can be detected. In this study, we performed $^1H$ NMR analyses of urine to monitor the ethanol and EtG. Urinary samples were collected over time from 5 male volunteers. We confirmed that ethanol and EtG signals could be detected with NMR spectroscopy. Ethanol signals increased immediately upon alcohol intake, but decreased sharply over time. In contrast, EtG signal increased and reached a maximum about 9 h later, after which the EtG signal decreased gradually and remained detectable after 20-25 h. Based on these results, we suggest that $^1H$ NMR spectroscopy may be used to identify ethanol non-oxidative metabolites without the need for sample pretreatment.

[ $T_2$ ]-relaxation Time Measurement of ex vivo $^1H$ MR Metabolite Peaks for Evaluation of Human Stomach Cancer

  • Mun Chi-Woong;Choi Ki-Sueng;Shin Oon-Jae;Yang Young-Ill;Chang Hee-Kyung;Hu Xiaoping;Eun Chung-Ki
    • Journal of Biomedical Engineering Research
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    • v.27 no.2
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    • pp.53-58
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    • 2006
  • In this study, transverse relaxation time (T2) measurement and the evaluation of the characteristics of the spectral peak related to stomach tissue metabolites were performed using ex vivo proton magnetic resonance spectroscopic imaging (MRSI) at 1.5-T MRI/S instruments. Thirty-two gastric tissues resected from 12 patients during gastric cancer surgery, of which 19 were normal tissue and 13 were cancerous tissue, were used to measure the $T_2$ of the magnetic resonance spectroscopy (MRS) peaks. The volume of interest data results from the MRSI measurements were extracted from the proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and were statistically analyzed. MR spectra were acquired using the chemical shift imaging (CSI) point resolved spectroscopy (CSI-PRESS) technique with the parameters of pulse repetition time (TR) and echo times (TE) TR/(TE1,TE2)=1500 msec/(35 msec, 144 msec), matrix $size=24{\times}24$, NA=1, and voxel $size=2.2{\times}2.2{\times}4mm^3$. In conclusion, the measured $T_2$ of the metabolite peaks, such as choline (3.21ppm) and lipid (1.33ppm), were significantly decreased (p<0.01 and p<0.05, respectively) in the cancerous stomach tissue.