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) relaxation of the tissue was found to be anisotropic and had two populations. When immersed in saline, the T(2) values were short and their relative populations were anisotropic. When immersed in PBS, the T(2) values increased and their relative populations became isotropic. These phenomena, also verified by proton double-quantum-filtered (DQF) NMR spectroscopy, were interpreted as the catalyzing effect of phosphate ions on proton exchange between water molecules. In the experiment on articular cartilage, the immersion of cartilage-bone blocks in PBS resulted in a significant reduction in the laminar appearance of cartilage on MRI (the magic angle effect). The quantitative T(2) anisotropy by microMRI at 13 microm pixel resolution and DQF NMR spectroscopy confirmed the substantial effect of PBS on the water dynamics in cartilage tissue blocks. This preliminary study has two important implications. For in vitro cartilage research, this work confirms the importance of the salt solution in which the specimen is stored - not all salts have the same effect on the measurable quantities in NMR and MRI. For in vivo cartilage diagnosis, especially using whole-body MRI scanners, this work suggests the possibility of using a suitable electrolyte as a novel contrast agent to assess the ultrastructural changes in cartilage due to tissue degradation.
journal_name
NMR Biomedjournal_title
NMR in biomedicineauthors
Zheng S,Xia Ydoi
10.1002/nbm.1294subject
Has Abstractpub_date
2009-02-01 00:00:00pages
158-64issue
2eissn
0952-3480issn
1099-1492journal_volume
22pub_type
杂志文章abstract::Organs consist of several types of cells with specialized functions. This cellular localization of function is often referred to as compartmentation. Due to the intrinsic low sensitivity of MR methods it is generally not possible in vivo to obtain images or spectra of single cells. Instead the MRS signal is the sum of...
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
abstract:PURPOSE:To develop a novel respiratory motion compensated three-dimensional (3D) cardiac magnetic resonance fingerprinting (cMRF) approach for whole-heart myocardial T1 and T2 mapping from a free-breathing scan. METHODS:Two-dimensional (2D) cMRF has been recently proposed for simultaneous, co-registered T1 and T2 mapp...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4370
更新日期:2020-10-01 00:00:00
abstract::The development and implementation of novel MRI pulse sequences remains challenging and laborious. Gradient waveforms are typically designed using a combination of analytical and ad hoc methods to construct each gradient waveform axis independently. This strategy makes coding the pulse sequence complicated, in additio...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4308
更新日期:2020-12-01 00:00:00
abstract::MRS provides a valuable tool for the non-invasive detection of brain γ-aminobutyric acid (GABA) in vivo. GABAergic dysfunction has been observed in the aging cerebellum. The study of cerebellar GABA changes is of considerable interest in understanding certain age-related motor disorders. However, little is known about...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3381
更新日期:2015-10-01 00:00:00
abstract::The intrinsic nonuniformities in the transmit radiofrequency field from standard quadrature volume resonators at high field are particularly problematic for localized MRS in areas such as the temporal lobe, where a low signal-to-noise ratio and poor metabolite quantification result from destructive B₁⁺ field interfere...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1638
更新日期:2011-08-01 00:00:00
abstract::The purpose of this work was to carry out diffusion tensor imaging (DTI) at multiple diffusion times Td in skeletal muscle in normal subjects and chronic exertional compartment syndrome (CECS) patients and analyze the data with the random permeable barrier model (RPBM) for biophysical specificity. Using an institution...
journal_title:NMR in biomedicine
pub_type: 临床试验,杂志文章
doi:10.1002/nbm.3087
更新日期:2014-05-01 00:00:00
abstract::Diffusion measurements were performed on the N-acetyl aspartate (NAA) signal in in situ brains (in vivo and post-mortem) and on in vitro brain tissue at 37 degrees C using wide ranges of b-values (from 0 up to 4.5 x 10(6) s/cm2 and 35.8 x 10(6) s/cm2 for the in vivo and the in vitro cases, respectively). In vivo and i...
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
abstract::One of the most commonly used methods for in vivo MRS detection of γ-aminobutyric acid (GABA) is the MEGA-point-resolved spectroscopy (MEGA-PRESS) technique. However, accurate quantification of GABA using MEGA-PRESS is complicated by spectral co-editing of macromolecular resonances. In this article, a new pulse sequen...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1688
更新日期:2011-12-01 00:00:00
abstract::Human tumor and skeletal muscle tissue was studied by means of in vivo 1H, 31P, and 13C MRS. The examinations were performed with a 1.5 T whole-body MR scanner equipped with a second RF system. Localized 1H and broadband proton-decoupled 31P and 13C MR spectra were obtained in measurement times of 5, 10 and 33 min, re...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940050402
更新日期:1992-07-01 00:00:00
abstract::An often-employed strategy to enhance signals in (31) P MRS is the generation of the nuclear Overhauser effect (NOE) by saturation of the water resonance. However, NOE allegedly increases the variability of the (31) P data, because variation is reported in NOE enhancements. This would negate the signal-to-noise (SNR) ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3455
更新日期:2016-03-01 00:00:00
abstract::Increased pulmonary lactate production is correlated with severity of lung injury and outcome in acute respiratory distress syndrome (ARDS) patients. This study was conducted to investigate the relative contributions of inflammation and hypoxia to the lung's metabolic shift to glycolysis in an experimental animal mode...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4380
更新日期:2020-11-01 00:00:00
abstract::The purpose of this work was to harmonize data acquisition and post-processing of single voxel proton MRS ((1) H-MRS) at 7 T, and to determine metabolite concentrations and the accuracy and reproducibility of metabolite levels in the adult human brain. This study was performed in compliance with local institutional hu...
journal_title:NMR in biomedicine
pub_type: 杂志文章,多中心研究
doi:10.1002/nbm.3252
更新日期:2015-03-01 00:00:00
abstract::The myeloproliferative leukemic virus (MPLV) induces within 2-3 weeks a massive infiltration of the adult mouse liver by hematopoietic leukemic cells. Since the metabolism of the infiltrated organ might be correlated with an interaction of two cell populations, it was decided to study the isolated hematopoietic cells ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940020106
更新日期:1989-06-01 00:00:00
abstract::A novel polarizer based on the dissolution-dynamic nuclear polarization (DNP) method has been designed, built and tested. The polarizer differs from those previously described by being designed with sterile use intent and being compatible with clinical use. The main features are: (1) an integral, disposable fluid path...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1682
更新日期:2011-10-01 00:00:00
abstract::The management and treatment of high-grade glioblastoma multiforme (GBM) and solitary metastasis (MET) are very different and influence the prognosis and subsequent clinical outcomes. In the case of a solitary MET, diagnosis using conventional radiology can be equivocal. Currently, a definitive diagnosis is based on h...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3163
更新日期:2014-09-01 00:00:00
abstract::The current study aims to evaluate the feasibility of creatine (Cr) chemical exchange saturation transfer (CEST)-weighted MRI at 7 T in the human brain by optimizing the saturation pulse parameters and computing contrast using a Z-spectral fitting approach. The Cr-weighted (Cr-w) CEST contrast was computed from phanto...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4176
更新日期:2019-12-01 00:00:00
abstract::We review several methods that have been developed to infer microstructural and physiological information about isotropic and anisotropic tissues from diffusion weighted images (DWIs). These include Diffusion Imaging (DI), Diffusion Tensor Imaging (DTI), isotropically weighted imaging, and q-space imaging. Just as DI ...
journal_title:NMR in biomedicine
pub_type: 杂志文章,评审
doi:10.1002/nbm.1940080707
更新日期:1995-11-01 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::The physiological status of anesthetized rats greatly influences blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). Monitoring of physiological parameters, particularly partial pressure of carbon dioxide (pCO(2)) levels in the blood, is therefore an important part in the design and ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.978
更新日期:2005-11-01 00:00:00
abstract::We introduce a new protocol to obtain very high-frame-rate cinematographic (Cine) MRI movies of the beating mouse heart within a reasonable measurement time. The method is based on a self-gated accelerated fast low-angle shot (FLASH) acquisition and compressed sensing reconstruction. Key to our approach is that we exp...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2883
更新日期:2013-04-01 00:00:00
abstract::The majority of functional MRI studies of pain processing in the brain use the blood oxygenation level-dependent (BOLD) imaging approach. However, the BOLD signal is complex as it depends on simultaneous changes in blood flow, vascular volume and oxygen metabolism. Arterial spin labeling (ASL) perfusion imaging is ano...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.2911
更新日期:2013-06-01 00:00:00
abstract::Results are presented from an in vivo study of human skin in which a zig-zag surface coil together with a three-pulse Fourier Series Window (FSW) protocol have been used to obtain minimally contaminated 31P skin spectra of the posterior calf. Phantom experiments indicate that while the fall-off in the B1 field profile...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(SICI)1099-1492(199608)9:5<195::AID-NBM416
更新日期:1996-08-01 00:00:00
abstract::An optimized semi-LASER sequence that is capable of acquiring artefact-free data with an echo time (TE) of 20.1 ms on a standard clinical 3 T MR system was developed. Simulations were performed to determine the optimal TEs that minimize the expected Cramér-Rao lower bound (CRLB) as proxy for quantification accuracy of...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.4324
更新日期:2020-09-01 00:00:00
abstract::31P Nuclear magnetic resonance spectroscopy has been used to investigate the combined effect of 70 mM ethanol administration and hypoxia on the energetic metabolism and cytosolic pH of the perfused liver isolated from naive, fasted or chronically ethanol-treated rats. Ethanol-treatment or fasting induce a similar 25% ...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.1940030306
更新日期:1990-06-01 00:00:00
abstract::Lung cancer is a primary cause of cancer deaths worldwide. Timely detection of this pathology is necessary to delay or interrupt lung cancer progression, ultimately resulting in a possible better prognosis for the patient. In this context, magnetic resonance imaging (MRI) is especially promising. Ultra-short echo time...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3790
更新日期:2017-11-01 00:00:00
abstract::This paper describes the development of a novel technique for functional MRI of the human brain at 0.135 microL resolution for a whole brain section. In comparison with conventional studies at 3 mm isotropic resolution or 27 microL voxel size, the method yields an improvement by a factor of 200. To achieve optimum ima...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.998
更新日期:2005-12-01 00:00:00
abstract::A recent analysis of the optimization of magnetization transfer experiments to estimate first-order rate constants is extended to the design of experiments for measuring these constants and T1 when both parameters are initially unknown. When the number of measurement times is fixed, an optimal design will consist of a...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(SICI)1099-1492(199605)9:3<135::AID-NBM404
更新日期:1996-05-01 00:00:00
abstract::The presence of the e4 allele of the apolipoprotein E (APOE) gene is the best-known genetic risk factor for Alzheimer's disease. In this study, we investigated the link between functional and behavioural differences and regional brain volume and cortical thickness differences in those who carry the e4 allele (e4+) and...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/nbm.3502
更新日期:2016-05-01 00:00:00
abstract::The potential for using pre-polarized liquids as contrast agents in vivo is investigated and the feasibility of the method demonstrated. In this study we show the enhancement obtained following intravenous delivery of pre-polarized saline into the antecubital vein of a volunteer. This form of contrast agent provides s...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(sici)1099-1492(199910)12:6<381::aid-nbm57
更新日期:1999-10-01 00:00:00
abstract::High-resolution MR imaging (312 microns in plane resolution) and MR spectroscopy (0.36 cm3 nominal voxel) have been performed on human frontal cortex using a 3 in surface coil. Localized proton spectra have been obtained from contiguous 6 x 6 x 10 mm voxels using one-dimensional phase encoding, TR 2000 ms and TE 31 ms...
journal_title:NMR in biomedicine
pub_type: 杂志文章
doi:10.1002/(SICI)1099-1492(199610)9:7<297::AID-NBM433
更新日期:1996-10-01 00:00:00