The required time of conventional magnetic resonance spectroscopic imaging technique is too long to be applied to clinic. It is necessary to develop the fast methods for magnetic resonance spectroscopic imaging. Nowadays there are 7 kinds of methods presented, which come from MRI techniques. In this contribution the conventional spectroscopic imaging and 7 sorts of fast spectroscopic imaging are elaborated. It is envisaged that more rapid imaging techniques will be designed, if these arbitrary trajectory reconstruction methods in MRI are applied to spectroscopic imaging.
Magnetic Resonance Imaging ; methods ; trends ; Magnetic Resonance Spectroscopy ; methods

Nuclear magnetic resonance (NMR) spectroscopy can be used to both identify and quantify chemicals from complex mixtures. Over the last several decades, significant technical and experimental advances have made quantitative nuclear magnetic resonance (qNMR) a valuable analytical tool for quantitative measurements of a wide variety of samples. This particular approach is now being exploited to characterize the metabolomes of many different biological samples and is called quantitative metabolomics or targeted metabolic profiling. In this review, some of the strengths, limitations of NMR-based quantitative metabolomics will be discussed as well as the practical considerations necessary for acquisition with an emphasis on their use for bioanalysis. Recent examples of the application of this particular approach to metabolomics studies will be also presented.
Magnetic Resonance Spectroscopy ; Metabolome ; Metabolomics ; methods

Owing to the worldwide obesity epidemic and the sedentary lifestyle in industrialized countries, the number of people with metabolic diseases is explosively increasing. Magnetic resonance spectroscopy (MRS), which is fundamentally similar to magnetic resonance imaging, can detect metabolic changes in vivo noninvasively. With its noninvasive nature, 1H, 13C and 31P MRS are being actively utilized in clinical and biomedical metabolic studies to detect lipids and important metabolites without ionizing radiation. 1H MRS can quantify lipid content in liver and muscle and can detect other metabolites, such as 2-hydroxyglutarate, in vivo. Of interest, many studies have indicated that hepatic and intramyocellular lipid content is inversely correlated with insulin sensitivity in humans. Thus, lipid content can be utilized as an in vivo biomarker for detecting early insulin resistance. Employing 13C MRS, hepatic glycogen synthesis and breakdown can be directly detected, whereas 31P MRS provides in vivo adenosine triphosphate (ATP) synthesis rates by saturation transfer methods in addition to ATP content. These in vivo data can be very difficult to assess by other methods and offer a critical piece of metabolic information. To aid the reader in understanding these new methods, fundamentals of MRS are described in this review in addition to promising future applications of MRS and its limitations.
Carbon-13 Magnetic Resonance Spectroscopy ; Humans ; Magnetic Resonance Imaging/methods ; *Magnetic Resonance Spectroscopy/methods ; Metabolic Diseases/*diagnosis ; Phosphorus Isotopes ; Protons

The accurate diagnosis and staging of hepatic fibrosis is crucial for treatment and prognosis of liver disease. The current gold standard is liver biopsy, but it cannot be used in population-based screening, and has well known drawbacks if used for monitoring of disease progression or treatment results. Functional MR, as a non-invasive method, is increasingly used in hepatic fibrosis and became the current hot spot. Most recently available functional MR imaging techniques including diffusion weighted imaging, perfusion weighted imaging and MR spectroscopy can detect cirrhosis or fibrosis reasonably accurately. However, to date only MR elastography has been able to stage fibrosis or diagnose mild disease. MR diffusion weighted appears next most promising.
Diffusion Magnetic Resonance Imaging ; Humans ; Liver Cirrhosis ; classification ; diagnosis ; Magnetic Resonance Imaging ; methods ; Magnetic Resonance Spectroscopy

BACKGROUNDReliable early prediction response to therapy and time-to-progression (TTP) remain an important goal of high-grade gliomas (HGGs) research. Proton magnetic resonance spectroscopy ((1)H-MRS) has been applied with variable success in clinical application, and we hypothesize that (1)H-MRS in predictive value should perform well as a marker of TTP in patients treated with radiotherapy (RT) after surgery.

METHODS(1)H-MRS was performed before surgery on 25 patients who had undergone resection of HGGs; then the ratios of lipid/creatine (Lip/Cr) and myo-inositol/creatine (mI/Cr) were determined in the solid tumor. RT response was classified as follows: complete resolution (CR), partial response (PR), stable disease (SD), and progressive disease (PD) by comparison of pre-treatment and post-radiotherapy scans. TTP was defined at the time to radiographic progression by MacDonald criteria. Correlation was evaluated between the ratios of Lip/Cr, mI/Cr and treatment response, TTP. The chi-square test and Pearson correlation test were used for data analyses.

RESULTSMultivariate analysis revealed that the prognostic value of spectroscopic variables was independent of age, sex, WHO histologic grade, extent of surgery, and Karnofsky score (KPS). The correlation between the ratios of lipid/Cr and TTP was significant (r = 0.894, P = 0.000), and between the ratios of mI/Cr and TTP was also significant (r = 0.891, P = 0.000). As predicted, RT response correlated significantly with TTP (r = 0.59, P = 0.002): median TTP was 49.9 days for patients with PD compared with 202.7 days for SD, 208.0 days for PR, and 234.5 days for CR.

CONCLUSIONThe ratios of Lip/Cr and mI/Cr of the solid tumor region before surgery could provide important information in predicting RT response and TTP in patients with HGGs treated by radiation alone after surgery.

The 1H-NMR fingerprints of three different species tibetan medicine sea buckthorn were established by 1H-HMR metabolomics to find out different motablism which could provide a new method for the quality evaluation of sea buckthorn. The obtained free induction decay (FID) signal will be imported into MestReNova software and into divide segments. The data will be normalized and processed by principal component analysis and.partial least squares discriminant analysis to perform pattern recognition. The results showed that 25 metabolites belonging to different chemical types were detected from sea buckthorn,including flavonoids, triterpenoids, amino acids, carbohydrates, fatty acids, etc. PCA and PLS-DA analysis showed three different varietiest of sea buckthorn that can be clearly separated by the content of L-quebrachitol, malic acid and some unidentified sugars, which can be used as the differences metabolites of three species of sea buckthorn. 1H-NMR-based metabonomies method had a holistic characteristic with sample preparation and handling. The results of this study can offer an important reference for the species identification and quality control of sea buckthorn.
Hippophae ; metabolism ; Magnetic Resonance Spectroscopy ; methods ; Medicine, Tibetan Traditional ; Metabolomics

To research on the effect of three different magnetic nanoparticles upon relaxation time of proton. The detection by magnetic resonance imaging (MRI) indicates that there is the effect of marked difference to right control experiment and to analyze the difference from theory. The result discloses that will be able to perform the experiment of molecular recognition using magnetic nanoparticles later.
Ferric Compounds ; chemistry ; Humans ; Magnetic Resonance Imaging ; instrumentation ; methods ; Magnetic Resonance Spectroscopy ; methods ; Magnetics ; Nanoparticles ; Protons

With the development of magnetic resonance (MR) technology, the concern is focused on molecular and physiological imaging besides structural information. Ultra high field MR scanner shows great superiority. 3. 0-T MR scanners provide almost two-fold signal-to-noise ratio (SNR) compared with a standard 1. 5-T MR scanner. The higher baseline SNR can be converted into a variety of alternative benefits. There are still some other changes brought about by 3. 0-T, such as higher sensitivity to motion, susceptibility effect, more difference in resonant frequency among different metabolites, and so on. These features may be a double-edged sword in structural and functional imaging. But with the ceaseless progress of the technology and gains in experience, 3. 0-T systems will provide more information and show more advantages.
Animals ; Humans ; Image Enhancement ; methods ; Magnetic Resonance Imaging ; instrumentation ; methods ; Magnetic Resonance Spectroscopy ; instrumentation ; Sensitivity and Specificity

The portable light-weight magnetic resonance imaging system can be deployed in special occasions such as Intensive Care Unit (ICU) and ambulances, making it possible to implement bedside monitoring imaging systems, mobile stroke units and magnetic resonance platforms in remote areas. Compared with medium and high field imaging systems, ultra-low-field magnetic resonance imaging equipment utilizes light-weight permanent magnets, which are compact and easy to move. However, the image quality is highly susceptible to external electromagnetic interference without a shielded room and there are still many key technical problems in hardware design to be solved. In this paper, the system hardware design and environmental electromagnetic interference elimination algorithm were studied. Consequently, some research results were obtained and a prototype of portable shielding-free 50 mT magnetic resonance imaging system was built. The light-weight magnet and its uniformity, coil system and noise elimination algorithm and human brain imaging were verified. Finally, high-quality images of the healthy human brain were obtained. The results of this study would provide reference for the development and application of ultra-low-field magnetic resonance imaging technology.
Humans ; Magnetic Resonance Imaging/methods* ; Magnetic Resonance Spectroscopy/methods* ; Head ; Equipment Design ; Magnets

The present study established a quality evaluation method for ginsenoside reference substances based on quantitative nuclear magnetic resonance(qNMR) spectroscopy. ~1H-NMR spectra were collected on Bruker Avance Ⅲ 500 MHz NMR spectrometer equipped with a 5 mm BBO probe. The acquire parameters were set up as follows: pulse sequence of 30°, D_1=20 s, probe temperature= 303 K, and the scan number = 32. Dimethyl terephthalate, a high-quality ~1H-qNMR standard, was used as the internal standard and measured by the absolute quantitative method. Methyl peaks of comparatively good sensitivity were selected for quantification, and linear fitting deconvolution was adopted to improve the accuracy of integration results. The qNMR spectroscopy-based method was established and validated, which was then used for the quality evaluation of ginsenoside Rg_1, ginsenoside Re, ginsenoside Rb_1, ginsenoside Rd, and notoginsenoside R_1. The results suggested that the content of these ginsenoside reference standards obtained from the qNMR spectroscopy-based method was lower than that detected by the normalization method in HPLC provided by the manufacturers. In conclusion, the qNMR spectroscopy-based method can ensure the quality of ginsenoside reference substances and provide powerful support for the accurate quality evaluation of Chinese medicine and its preparations. The qNMR spectroscopy-based method is simple, rapid, and accurate, which can be developed for the quantitative assay of Chinese medicine standard references.
Chromatography, High Pressure Liquid/methods* ; Ginsenosides/analysis* ; Magnetic Resonance Spectroscopy/methods* ; Proton Magnetic Resonance Spectroscopy ; Reference Standards