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1.
Diagnosing diabetic nephropathy by 1H NMR metabonomics of serum 总被引:2,自引:0,他引:2
Mäkinen VP Soininen P Forsblom C Parkkonen M Ingman P Kaski K Groop PH Ala-Korpela M;FinnDiane Study Group 《Magma (New York, N.Y.)》2006,19(6):281-296
Object: The most severe complication of type 1 diabetes (T1DM) is diabetic nephropathy. It is associated with a high risk of cardiovascular
complications and premature death and requires early detection to be efficiently treated. The clinical practice to diagnose
diabetic nephropathy is also a non-optimal and tedious set up based on albumin excretion rate in multiple overnight or 24h
urine samples. Conversely, in this study, these independent diagnostic data are used to provide a realistic testing case for
applying 1H NMR metabonomics of serum in a diagnostic fashion.
Materials and Methods: 182 T1DM and 21 non-diabetic (non-T1DM) individuals were studied. The 1H NMR of serum at 500 MHz was targeted at two molecular windows: lipoprotein lipids and low-molecular-weight metabolites.
Results: T1DM and non-T1DM individuals were exclusively separated by 1H NMR. For diabetic nephropathy diagnosis in the T1DM patients, 1H NMR data (and clinical biochemistry data) gave a sensitivity of 87.1% (83.9%) and a specificity of 87.7% (95.9%). The predictive
values of positive and negative tests were 89.0% (95.5%) and 83.6% (79.2%), respectively.
Conclusions: 1H NMR metabonomics clearly distinguishes metabolic characteristics of T1DM and appears approximately as good a means to diagnose
diabetic nephropathy from serum as an advanced set of biochemical variables. 相似文献
2.
Vít Herynek Kateřina Růžičková Pavla Jendelová Eva Syková Milan Hájek 《Magma (New York, N.Y.)》2009,22(4):211-220
Object Metabolite changes in an experimental lesion in the rat cortex and in the contralateral hemisphere after the intravenous administration
of mesenchymal stem cells (MSCs) were assessed by proton MR spectroscopy to verify the impact of the cell treatment on the
brain tissue.
Materials and methods Wistar rats with a photochemical cortical lesion and transplanted MSCs or sham transplanted rats were examined. Proton spectra
were obtained from the lesion and from the contralateral cortex.
Results Magnetic resonance spectroscopy revealed a gradual recovery of the damaged tissue; however, we found no significant differences
in metabolite concentrations in the lesioned hemisphere between treated and untreated animals. Higher concentrations of glutamate
and N-acetyl aspartate were found in the contralateral hemisphere in cell-treated animals compared to untreated ones. Lesioned
animals showed neurogenesis in the contralateral hemisphere; the number of newly generated cells in stem cell-treated animals
was 50% higher than those observed in untreated animals.
Conclusion No direct impact of cell transplantation was observed in the lesion. However, changes in the contralateral hemisphere suggest
that the transplanted MSCs might stimulate repair processes and plasticity resulting in the generation of newborn cells, which
might enable the faster adoption of the damaged tissue’s function by healthy tissue. 相似文献
3.
4.
Azaroual N Imbenotte M Cartigny B Leclerc F Vallée L Lhermitte M Vermeersch G 《Magma (New York, N.Y.)》2000,10(3):177-182
Analysis of biological fluids by proton and carbon nuclear magnetic resonance spectroscopy (1H and13C NMR) is a promising tool in clinical biology. We used this method for rapid toxicological screening in the case of two suicide
attempts. For each case, a urine sample was analysed at 300 MHz by 1D and 2D sequences (TOCSY and HMBC) in a short experimental
time. Quantification was performed by peak integration on the 1D1H NMR spectrum. For the two patients, results showed the same resonances of the major metabolite, valproyl-O-glucuronide at concentrations of 121 and 44 mmol/l. 相似文献
5.
John M. Pearce Mary C. Mahoney Jing-Huei Lee Wen-Jang Chu Kim M. Cecil Stephen M. Strakowski Richard A. Komoroski 《Magma (New York, N.Y.)》2013,26(3):337-343
Object
The relative amounts of choline (Cho), phosphocholine (PC), and glycerophosphocholine (GPC) may be sensitive indicators of breast cancer and the degree of malignancy. Here we implement some simple modifications to a previously developed 1H NMR analysis of fine-needle-aspirate (FNA) biopsies designed to yield sufficient spectral resolution of Cho, PC, and GPC for usable relative quantitation of these metabolites.Materials and methods
FNA biopsies of eighteen breast lesions were examined using our modified procedure for direct 1H NMR at 400 MHz. Resonances of choline metabolites and potential interferences were fit using the computer program NUTS.Results
Quantitation of PC, GPC, and Cho relative to each other and to (phospho)creatine was obtained for eleven confirmed cases of infiltrating ductal carcinoma. Reliable results could not be obtained for the remaining cases primarily due to interference from lidocaine anesthetic.Conclusion
Some simple modifications of a previously developed 1H NMR analysis of FNAs yielded sufficient spectral resolution of Cho, PC, and GPC to permit usable relative quantitation at 400 MHz. In 9 of the 11 quantified cases the sum of GPC and Cho exceeded 42 % of the total choline-metabolite peak area. 相似文献6.
Mika Ala-Korpela Jussi-Pekka Usenius Jyrki Keisala Aad van den Boogaart Pauli Vainio Jukka Jokisaari Seppo Soimakallio Risto Kauppinen 《Magma (New York, N.Y.)》1995,3(3-4):129-136
We present here a combination of time-domain signal analysis procedures for quantification of human brainin vivo
1H NMR spectroscopy (MRS) data. The method is based on a separate removal of a residual water resonance followed by a frequency-selective time-domain line-shape fitting analysis of metabolite signals. Calculation of absolute metabolite concentrations was based on the internal water concentration as a reference. The estimated average metabolite concentrations acquired from six regions of normal human brain with a single-voxel spin-echo technique for theN-acetylaspartate, creatine, and choline-containing compounds were 11.4±1.0,6.5±0.5, and 1.7±0.2 mmol kg–1 wet weight, respectively. The time-domain analyses ofin vivo
1H MRS data from different brain regions with their specific characteristics demonstrate a case in which the use of frequency-domain methods pose serious difficulties. 相似文献
7.
Jürgen Schiller Lama Naji Daniel Huster Jörn Kaufmann Klaus Arnold 《Magma (New York, N.Y.)》2001,13(1):19-27
Rheumatic diseases are accompanied by a progressive destruction of the cartilage layer of the joints. Despite the frequency of the disease, degradation mechanisms are not yet understood and methods for early diagnosis are not available. Although some information on pathogenesis could be obtained from the analysis of degradation products of cartilage supernatants, the most direct information on degradation processes would come from the native cartilage as such. We have used1H as well as13C HR-MAS (high resolution magic angle spinning) NMR spectroscopy to obtain suitable line-widths of NMR resonances of native cartilage. ID and 2D NMR spectra of native cartilage were compared with those of enzymatically-treated (collagenase and pa pain) samples. In the1H NMR spectra of native cartilage, resonances of polysaccharides, lipids and a few amino acids of collagen were detectable, whereas the13C NMR spectra primarily indicated the presence of chondroitin sulfate. Treatment with papain resulted only in small changes in the1H NMR spectrum, whereas a clear diminution of all resonances was detectable in the13C NMR spectra. On the other hand, treatment with collagenase caused the formation of peptides with an amino acid composition typical for collagen (glycine, proline, hydroxyproline and lysine). It is concluded that the HR-MAS NMR spectra of cartilage may be of significance for the investigation of cartilage degradation since they allow the fast evaluation of cartilage composition and only very small amounts of sample are required. © 2001 Elsevier Science B.V. All rights reserved. 相似文献
8.
2H quadrupolar splitting of deuterated water molecules is a sensitive measure of the order and density of the collagen fibers
in articular cartilage. In the calcified zone, near the bone, two pairs of quadrupolar split satellites were previously observed.
To examine whether the large splitting observed originates from the presence of calcium ions and hydroxyapatite, one-dimensional
2H single and double quantum filtered spectroscopic imaging were performed on articular cartilage-bone plugs before and after
decalcification. After decalcification, the magnitude splitting of the two pairs of satellites did not change and orientation
dependency was kept. However, the intensity of the large splitting was greatly enhanced. According to these results the two
pairs of satellites do not stem from the presence of calcium ions and hydroxyapatite but originate from the presence of two
groups of collagen fibers with different degrees of hydration. The enhanced intensity of the large splitting is attributed
to an increased amount of water molecules that fill the void, resulting from the removal of hydroxyapatite, which resides
near the fibers responsible for the large splitting. The quadrupolar splitting observed in the trabecular bone was not orientation-dependent,
indicating a random orientation of the collagen fibers in that tissue. 相似文献
9.
We used proton spectroscopy to compare metabolite levels in infarcted brain tissue with the levels in corresponding normal white matter. In a preliminary study of six patients, the ratios (mean ± standard deviation) were 0.72±0.25 (p=0.04) for choline, 0.41±0.24 (p=0.002) for creatine, and 0.21±0.22 (p<0.001) forN-acetylaspartate. 相似文献
10.
Objective
Recent years have seen an increased interest in combining MRI thermometry with devices capable of destroying malignancies by heat ablation. Expected from the MR protocols are accurate and fast thermal characterizations, providing real time feedback on restricted tissue volumes and/or rapidly moving organs like liver. This article explores the potential advantages of relying on spatiotemporally encoded (SPEN) sequences for retrieving real-time thermometric images based on the water’s proton resonance frequency (PRF) shifts.Materials and methods
Hybrid spatiotemporal/k-space encoding single-scan MRI experiments were implemented on animal and human scanners, and their abilities to deliver single- and multi-slice real-time thermometric measurements based on PRF-derived phase maps in phantoms and in vivo, were compared against echo planar imaging (EPI) and gradient-echo counterparts.Results
Under comparable acquisition conditions, SPEN exhibited advantages vis-à-vis EPI in terms of dealing with inhomogeneous magnetic field distortions, with shifts arising due to changes in the central frequency offsets, with PRF distributions, and for zooming into restricted fields-of-view without special pulse sequence provisions.Conclusion
This work confirms the ability of SPEN sequences, particularly when implemented under fully-refocused conditions, to exploit their built-in robustness to shift- and field-derived inhomogeneities for monitoring thermal changes in real-time under in vitro and in vivo conditions. 相似文献11.
Tedros Bezabeh Omkar B. Ijare Nils Albiin Urban Arnelo Bo Lindberg Ian C. P. Smith 《Magma (New York, N.Y.)》2009,22(5):267-275
Objective
There are no specific biomarkers available for the definitive diagnosis of pancreatic cancer. Analysis of d-glucuronic acid (GlcUA) in bile could be valuable in this regard. 相似文献12.
Brad R. Cohn Bonnie N. Joe Shoujun Zhao John Kornak Vickie Y. Zhang Rahwa Iman John Kurhanewicz Kiarash Vahidi Jingwei Yu Aaron B. Caughey Mark G. Swanson 《Magma (New York, N.Y.)》2009,22(6):343-352
Object
To establish and compare normative metabolite concentrations in 2nd and 3rd trimester human amniotic fluid samples in an effort to reveal metabolic biomarkers of fetal health and development.Materials and methods
Twenty-one metabolite concentrations were compared between 2nd (15–27 weeks gestation, N = 23) and 3rd (29–39 weeks gestation, N = 27) trimester amniotic fluid samples using 1H high resolution magic angle spinning (HR-MAS) spectroscopy. Data were acquired using the electronic reference to access in vivo concentrations method and quantified using a modified semi-parametric quantum estimation algorithm modified for high-resolution ex vivo data.Results
Sixteen of 21 metabolite concentrations differed significantly between 2nd and 3rd trimester groups. Betaine (0.00846±0.00206 mmol/kg vs. 0.0133±0.0058 mmol/kg, P < 0.002) and creatinine (0.0124±0.0058 mmol/kg vs. 0.247±0.011 mmol/kg, P < 0.001) concentrations increased significantly, while glucose (5.96±1.66 mmol/kg vs. 2.41±1.69 mmol/kg, P < 0.001), citrate (0.740±0.217 mmol/kg vs. 0.399±0.137 mmol/kg, P < 0.001), pyruvate (0.0659±0.0103 mmol/kg vs. 0.0299±0.286 mmol/kg, P < 0.001), and numerous amino acid (e.g. alanine, glutamate, isoleucine, leucine, lysine, and valine) concentrations decreased significantly with advancing gestation. A stepwise multiple linear regression model applied to 50 samples showed that gestational age can be accurately predicted using combinations of alanine, glucose and creatinine concentrations.Conclusion
These results provide key normative data for 2nd and 3rd trimester amniotic fluid metabolite concentrations and provide the foundation for future development of magnetic resonance spectroscopy (MRS) biomarkers to evaluate fetal health and development. 相似文献13.
Terpstra M Vaughan TJ Ugurbil K Lim KO Schulz SC Gruetter R 《Magma (New York, N.Y.)》2005,18(5):276-282
Objective: Quantitation of glutathione (GSH) in the human brain in vivo using short echo time 1 H NMR spectroscopy is challenging because GSH resonances are not easily resolved. The main objective of this study was to
validate such quantitation in a clinically relevant population using the resolved GSH resonances provided by edited spectroscopy.
A secondary objective was to compare several of the neurochemical concentrations quantified along with GSH using LCModel analysis
of short echo time spectra in schizophrenia versus control.
Materials and Methods: GSH was quantified at 4T from short echo STEAM spectra and MEGA-PRESS edited spectra from identical volumes of interest
(anterior cingulate) in ten volunteers. Neurochemical profiles were quantified in nine controls and 13 medicated schizophrenic
patients.
Results: GSH concentrations as quantified using STEAM, 1.6 ± 0.4 μmol/g (mean ± SD, n=10), were within error of those quantified using edited spectra, 1.4 ± 0.4 μmol/g, and were not different (p=0.4). None of the neurochemical measurements reached sufficient statistical power to detect differences smaller than 10%
in schizophrenia versus control. As such, no differences were observed.
Conclusions: Human brain GSH concentrations can be quantified in a clinical setting using short-echo time STEAM spectra at 4T. 相似文献
14.
This study reports proton relaxation times of water and metabolites in soleus and tibialis anterior muscles of young healthy volunteers at 3 T. The results are in agreement with data reported for 1.5 and 4 T, showing a steady increase of spin-lattice relaxation times of water, creatine and lipids with B0 and no effect of B0 on spin–spin relaxation. Comparison between muscles revealed a longer spin–spin relaxation time of water in soleus than in tibialis anterior muscle (31±1 ms vs. 28±1 ms, p<0.05). These data can be applied to relaxation correction for the absolute quantification of skeletal muscle metabolite concentrations and further sequence optimization. 相似文献
15.
Xiaoyan Pan Martin Wilson Carmel McConville Theodoros N. Arvanitis Risto A. Kauppinen Andrew C. Peet 《Magma (New York, N.Y.)》2012,25(6):479-485
Object
Cytoplasmic lipid droplets (LDs) are dynamic cellular organelles; their accumulation is associated with several cellular processes, such as cell proliferation, apoptosis and necrosis. 1H Nuclear Magnetic Resonance (NMR) spectroscopy detects resonances from lipids present in cytoplasmic (LDs); an understanding of the relationship between LD characteristics and NMR lipid signals is important.Materials and methods
In this study, five nervous system cancer cell lines were investigated. Nile red staining was used to measure the diameter of LDs. High-resolution magic angle spinning NMR (HR-MAS) was performed on harvested cell pellets to quantify the patterns of lipid signals.Results
LDs were present in all five cell lines with different morphology. An average LD diameter of approximately 0.2???m was found in all cell types. Diameter of the largest LDs varied across the cell lines. The intensity of NMR lipid signals varied greatly between cell types, and a good correlation was found between total volume of LDs and the proton NMR lipid signal intensity at 0.9 and 1.3?ppm.Conclusion
The correlation implied that little NMR signal is detected from LDs of diameters less than approximately 0.34???m, most likely due to restriction of rotational motion of the lipids. 相似文献16.
Magnetization transfer characteristics in atherosclerotic plaque components assessed by adapted binomial preparation pulses 总被引:1,自引:0,他引:1
Mathilde Pachot-Clouard Françoise Vaufrey Luc Darrasse Jean-François Toussainti 《Magma (New York, N.Y.)》1998,7(1):9-15
Increasing the contrast between atheromatous plaque components is a major issue in cardiovascular MRI research. It would allow one to identify unstable plaque by differentiating the lipid core associated with vulnerability, from the fibrous cap, considered as a factor of stability. T2 and diffusion-weighted imaging have already provided satisfying results. Magnetization transfer (MT) between restricted protons Hr and free-water protons Hf could achieve a different contrast related to collagen and lipoprotein macromolecules present in the fibrous cap and lipid core, respectively. The purpose of this work was to evaluate in vitro the MT effect produced by adapted T2-selective 1-3-3-1 binomial pulses on isolated samples of atheromatous arteries at 3 T. A method based on simulation was used in order to improve the MT specificity: it is shown that 50% 1-3-3-1 pulses (the percentage indicating the level of Hr saturation) allow an estimation of T2r, the Hr T2. Using this technique, magnetization transfer was observed for the first time in atherosclerotic plaque components, an effect more pronounced for the fibrous cap and media than for the lipid core and advantitia. The T2r estimation gave values ranging from 20 to 25 μs for the four samples. This preliminary study provides a basis for establishing an MT imaging sequence of atheromatous arteries, by using 50% 1-3-3-1 pulses calibrated for saturating protons with a 20 μs T2. This MT protocol should be further compared to T2 and diffusion-weighted imaging. 相似文献
17.
叙述了能够全面检测氢冷机组氢气品质参数的 QQFX- 型智能在线氢气分析仪研制的背景及其意义。介绍了该系统的组成部分 ,各自的功能、仪器的参数以及它的技术特点 ,该仪器除在电力系统的氢冷机组使用外 ,还可应用于石化、航天等领域 相似文献
18.
Serriere S Barantin L Seguin F Tranquart F Nadal-Desbarats L 《Magma (New York, N.Y.)》2011,24(5):267-275
Object
The impact of inflammation in utero on amniotic fluid composition, the delivery term and the number of newborn rats per litter was investigated. The growth of newborns during the first fourteen days of life was analysed. 相似文献19.
Sokół M 《Magma (New York, N.Y.)》2001,12(2-3):177-183
Short echo time (TE) in vivo PRESS1H MR spectra (2 T. TE = 35 ms) of normal brain were fitted in the frequency domain using the second derivative method. In
this approach, local maxima and hidden peaks are found as local minima of spectrum second derivative. The Lorentzian robust
minimisation procedure (referred to as maximum likelihood or m-estimate fitting) using Levenburg -Marquardt non-linear fitting
engine was applied. Spectral lines were approximated under the assumption of the mixed Lorentzian/Gaussian lineshapes. The
same procedure was applied to 18 proton spectra. The number of peaks found within the range of 0.74/4.2 parts per million
(ppm) was 52 ± 3 and their positions were almost the same. The fitted lines were assigned on the basis of the J-pattern recalculated
for the field strength of 2 T and by comparing the chemical shifts with the shifts in the single compound spectra. The ratios
of main metabolites, such as NAA/Cr, Cho/Cr, Cho/NAA and ml/Cr, are in accord with those obtained earlier using the software
supplied with the MR imager and the absolute concentrations ofN-acetylaspartate (NAA). choline containing compounds (Cho),myo Inositol (ml), glucose (Gle) and glutamate (Glu) obtained from the fit agree with those reported in literature, which confirms
the usefulness of the second derivative method in routine analyses of1H MR brain spectra. 相似文献
20.
Comparison of in vivo1H MRS of human brain tumours with1H HR-MAS spectroscopy of intact biopsy samples in vitro 总被引:4,自引:1,他引:3
Sarah J. Barton Franklyn A. Howe Andrew M. Tomlins Simon A. Cudlip Jeremy K. Nicholson B. Anthony Bell John R. Griffiths 《Magma (New York, N.Y.)》1999,8(2):121-128
High resolution magic angle spinning (MAS)1H nuclear magnetic resonance (NMR) spectroscopy has been employed to study intact human brain tumour tissue and comparison
with the corresponding in vivo spectrum has been made. Two dimensional1H MAS-NMR measurements, including J-resolved and homonuclear shift correlation spectra, were obtained to aid metabolite signal
assignment. MAS gave greatly improved line-shape and reduced line-width in comparison to conventional high resolution in vivo1H MRS of intact tissue, permitting the simultaneous detection of cellular lipids and metabolites. The technique provides the
most direct method for comparison of in vivo spectra with high resolution spectra in vitro and hence allows more reliable
peak assignment of in vivo1H MRS spectra. 相似文献