Abstract:
:The leakage of metabolites from frozen and thawed tissue biopsies was measured semi-quantitatively by high-field (8.5 T) proton MRS. Human prostate and rat brain tissue specimens, frozen within 1 min of collection, lost significant and variable amounts of diagnostic metabolites immediately upon thawing. For prostate tissue 30-50% of initial total choline compounds, total creatines and citrate were detected in the collection buffer immediately after thawing. The widely used protocol for MR assessment of tissue biopsies, which involves washing of thawed tissue samples in fresh buffer, results in loss of large and unpredictable amounts of possibly diagnostic metabolites prior to MRS. This reduces the reproducibility of MR analysis of tissue biopsies and compromises the reliable identification of MR spectral patterns diagnostic of tissue pathology. The problem can be avoided by minimizing the volume of storage buffer, omitting tissue washing and performing MRS measurements on the tissue immersed in the original storage buffer.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Bourne R,Dzendrowskyj T,Mountford Cdoi
10.1002/nbm.815subject
Has Abstractpub_date
2003-04-01 00:00:00pages
96-101issue
2eissn
0952-3480issn
1099-1492journal_volume
16pub_type
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pub_type: 杂志文章
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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更新日期:2021-01-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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abstract::Following the impetus of early clinical and experimental investigations, in vivo and in vitro MRS studies of tumours pointed in the eighties to the possible significance of signals arising from phospholipid (PL) precursors and catabolites as novel biochemical indicators of in vivo tumour progression and response to th...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
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更新日期:1999-11-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
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journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.692
更新日期:2001-04-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199804)11:2<67::aid-nbm503
更新日期:1998-04-01 00:00:00
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journal_title:NMR in biomedicine
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更新日期:2020-11-02 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.991
更新日期:2005-12-01 00:00:00
abstract::Chemical exchange saturation transfer (CEST) can offer information about protons associated with mobile proteins through the amide proton transfer (APT) effect, which has been shown to discriminate tumor from healthy tissue and, more recently, has been suggested as a prognosticator of response to therapy. Despite this...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2947
更新日期:2013-10-01 00:00:00
abstract::Traditional methods of measuring magnetization in magnetic fluid samples, such as vibrating sample magnetometry (VSM), are typically limited to maximum field strengths of about 1 T. This work demonstrates the ability of MRI to measure the magnetization associated with two commercial MRI contrast agents at 3 T by compa...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1412
更新日期:2009-10-01 00:00:00
abstract::This paper describes the use of off-resonance saturation to further manipulate the blood oxygenation level dependent (BOLD) contrast of fMRI. A customized narrow bandwidth radiofrequency pulse, applied with a range of frequency offsets prior to selection of each slice, was designed and incorporated into a gradient ech...
journal_title:NMR in biomedicine
pub_type: 杂志文章
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更新日期:1997-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1297
更新日期:2009-02-01 00:00:00
abstract::A number of NMR spectroscopic and microscopic MRI (microMRI) techniques were used to study proton dynamics in canine tendon and articular cartilage immersed in normal saline solution (NaCl solution) and high-concentration phosphate-buffered saline (PBS) solution. In a proton CPMG experiment on tendons, the T(2) relaxa...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1294
更新日期:2009-02-01 00:00:00
abstract::Determination of the apparent diffusion coefficient (ADC) of the prostate in men (n = 60) with raised prostate-specific antigen (PSA) or an abnormal digital rectal examination (DRE) prior to transrectal ultrasound (TRUS) guided biopsy using endorectal DWI is reported. Patients were categorized into different groups ba...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1114
更新日期:2007-08-01 00:00:00
abstract::This review highlights various magnetic resonance image (MRI) segmentation algorithms that employ pattern recognition. The procedures are grouped into two categories: low- to intermediate-level, and high-level image processing. The former consists of grey level histogram analysis, texture definition, edge identificati...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1099-1492(199806/08)11:4/5<157::aid-
更新日期:1998-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3849
更新日期:2018-01-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4118
更新日期:2019-09-01 00:00:00
abstract::During the measurement of hyperpolarized 129 Xe magnetic resonance imaging (MRI), the diffusion-weighted imaging (DWI) technique provides valuable information for the assessment of lung morphometry at the alveolar level, whereas the chemical shift saturation recovery (CSSR) technique can evaluate the gas exchange func...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3730
更新日期:2017-08-01 00:00:00
abstract::Early imaging or blood biomarkers of tumor response is needed to customize anti-tumor therapy on an individual basis. This study evaluates the sensitivity and relevance of five potential MRI biomarkers. Sixty nude rats were implanted with human glioma cells (U-87 MG) and randomized into three groups: one group receive...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1611
更新日期:2011-06-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3308
更新日期:2015-06-01 00:00:00
abstract:INTRODUCTION:Sarcoidosis is a systemic granulomatous disease affecting in particular the respiratory tract. Cardiac magnetic resonance (CMR), including a measurement of T1 relaxation time, could potentially detect early stadia of sarcoidosis of the heart. The study aims to assess T1 mapping in the detection of early ca...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4388
更新日期:2020-11-01 00:00:00
abstract::The processes of tumor invasion and metastasis have been well characterized at the molecular level, and numerous biomarkers of tumor aggressiveness have been discovered. Molecular imaging offers the opportunity to depict specific cell markers relevant to tumor aggressiveness. Here, we describe the role of MRI in ident...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1590
更新日期:2011-07-01 00:00:00
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journal_title:NMR in biomedicine
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.3905
更新日期:2018-06-01 00:00:00
abstract::Natural abundance proton-decoupled (13)C magnetic resonance spectroscopy was used to establish the in vivo lipid composition of normal adipose tissue and the corresponding effects of altered lipid diets. Experiments were performed on a standard 1.5 T clinical MR scanner using a double-tuned (1)H-(13)C coil. Peaks from...
journal_title:NMR in biomedicine
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.824
更新日期:2003-05-01 00:00:00
abstract::In this study, we have performed simulations to address the effects of diffusion encoding parameters, signal-to-noise ratio (SNR) and T2 on skeletal muscle diffusion tensor indices and fiber tracts. Where appropriate, simulations were corroborated and validated by in vivo diffusion tensor imaging (DTI) of human skelet...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2959
更新日期:2013-11-01 00:00:00
abstract::Citicoline supplementation has been used to ameliorate memory disturbances in older people and those with Alzheimer's disease. This study used MRS to characterize the effects of citicoline on high-energy phosphate metabolites and constituents of membrane synthesis in the frontal lobe. Phosphorus ((31)P) metabolite dat...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1281
更新日期:2008-11-01 00:00:00
abstract::Biomarkers of early response to treatment have the potential to improve cancer therapy by allowing treatment to be tailored to the individual. Alterations in lipids detected by in vivo MRS have been suggested as noninvasive biomarkers of cell stress and early indicators of cell death. An improved understanding of the ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2796
更新日期:2012-11-01 00:00:00