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Improved diagnostic accuracy in differentiating malignant and benign lesions using single-voxel proton MRS of the breast at 3 T MRI

Suppiah S, Rahmat K, Mohd-Shah MN, Azlan CA, Tan LK, Aziz YF, et al.

Clin Radiol, 2013 Sep;68(9):e502-10.
PMID: 23706826 DOI: 10.1016/j.crad.2013.04.002

To investigate the diagnostic accuracy of single-voxel proton magnetic resonance spectroscopy (SV (1)H MRS) by quantifying total choline-containing compounds (tCho) in differentiating malignant from benign lesions, and subsequently, to analyse the relationship of tCho levels in malignant breast lesions with their histopathological subtypes.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods
Fulltext A Time-Domain NMR Study of the State of Water in Wet Granules with Different Fillers and Its Contribution to the Wet Granulation Process and to the Characteristics of Granules

Ito T, Okada K, Leong KH, Hirai D, Hayashi Y, Kumada S, et al.

Chem Pharm Bull (Tokyo), 2019;67(3):271-276.
PMID: 30828004 DOI: 10.1248/cpb.c18-00888

The different states of water incorporated in wet granules were studied by a low-field benchtop 1H-NMR time-domain NMR (TD-NMR) instrument. Wet granules consisting different fillers [cornstarch (CS), microcrystalline cellulose (MCC), and D-mannitol (MAN)] with different water contents were prepared using a high-speed granulator, and then their spin-spin relaxation time (T2) was measured using the NMR relaxation technique. The experimental T2 relaxation curves were analyzed by the two-component curve fitting, and then the individual T2 relaxation behaviors of solid and water in wet granules were identified. According to the observed T2 values, it was confirmed that the molecular mobility of water in CS and MCC granules was more restricted than that in the MAN granule. The state of water appeared to be associated with the drying efficiency and moisture absorption capacity of wet granules. Thus, it was confirmed that the state of water significantly affected the wet granulation process and the characteristics of the resultant granules. In the final phase of this study, the effects of binders on the molecular mobility of water in granulation fluids and wet granules were examined. The state of water in granulation fluids was substantially changed by changing the binders. The difference was still detected in wet granules prepared by addition of these fluids to the fillers. In conclusion, TD-NMR can offer valuable knowledge on wet granulation from the viewpoint of molecular mobility of water.

Matched MeSH terms: Proton Magnetic Resonance Spectroscopy/methods*
Optimization of cell disruption methods for efficient recovery of bioactive metabolites via NMR of three freshwater microalgae (chlorophyta)

Ma NL, Teh KY, Lam SS, Kaben AM, Cha TS

Bioresour Technol, 2015 Aug;190:536-42.
PMID: 25812996 DOI: 10.1016/j.biortech.2015.03.036

This study demonstrates the use of NMR techniques coupled with chemometric analysis as a high throughput data mining method to identify and examine the efficiency of different disruption techniques tested on microalgae (Chlorella variabilis, Scenedesmus regularis and Ankistrodesmus gracilis). The yield and chemical diversity from the disruptions together with the effects of pre-oven and pre-freeze drying prior to disruption techniques were discussed. HCl extraction showed the highest recovery of oil compounds from the disrupted microalgae (up to 90%). In contrast, NMR analysis showed the highest intensity of bioactive metabolites obtained for homogenized extracts pre-treated with freeze-drying, indicating that homogenizing is a more favorable approach to recover bioactive substances from the disrupted microalgae. The results show the potential of NMR as a useful metabolic fingerprinting tool for assessing compound diversity in complex microalgae extracts.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods*
AChE inhibitor: a regio- and stereo-selective 1,3-dipolar cycloaddition for the synthesis of novel substituted 5,6-dimethoxy spiro[5.3']-oxindole-spiro-[6.3″]-2,3-dihydro-1H-inden-1″-one-7-(substituted aryl)-tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazole

Ashraf Ali M, Ismail R, Choon TS, Kumar RS, Osman H, Arumugam N, et al.

Bioorg Med Chem Lett, 2012 Jan 1;22(1):508-11.
PMID: 22142546 DOI: 10.1016/j.bmcl.2011.10.087

Pyrrolothiazolyloxindole analogues share vital pharmacological properties, considered useful in Alzheimer's disease (AD). The aim of this study was synthesis and evaluate pyralothiazolyloxindole analogues if possess acetyl cholinesterase (AChE) inhibitory activity. The easily accessible one-pot synthesis of these compounds resulted to be significantly less difficult and expensive than that of donepezil. Several compounds possess anti-cholinesterase activity in the order of micro and sub-micromolar. Particularly, compound was the most potent inhibitors of the series against acetyl cholinesterase enzyme with IC(50) 0.11μmol/L.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods
Fulltext Metabolomic profiles of hepatocellular carcinoma in a European prospective cohort

Fages A, Duarte-Salles T, Stepien M, Ferrari P, Fedirko V, Pontoizeau C, et al.

BMC Med, 2015 Sep 23;13:242.
PMID: 26399231 DOI: 10.1186/s12916-015-0462-9

BACKGROUND: Hepatocellular carcinoma (HCC), the most prevalent form of liver cancer, is difficult to diagnose and has limited treatment options with a low survival rate. Aside from a few key risk factors, such as hepatitis, high alcohol consumption, smoking, obesity, and diabetes, there is incomplete etiologic understanding of the disease and little progress in identification of early risk biomarkers.
METHODS: To address these aspects, an untargeted nuclear magnetic resonance metabolomic approach was applied to pre-diagnostic serum samples obtained from first incident, primary HCC cases (n = 114) and matched controls (n = 222) identified from amongst the participants of a large European prospective cohort.
RESULTS: A metabolic pattern associated with HCC risk comprised of perturbations in fatty acid oxidation and amino acid, lipid, and carbohydrate metabolism was observed. Sixteen metabolites of either endogenous or exogenous origin were found to be significantly associated with HCC risk. The influence of hepatitis infection and potential liver damage was assessed, and further analyses were made to distinguish patterns of early or later diagnosis.
CONCLUSION: Our results show clear metabolic alterations from early stages of HCC development with application for better etiologic understanding, prevention, and early detection of this increasingly common cancer.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods*
Metabolite Variation in Lean and Obese Streptozotocin (STZ)-Induced Diabetic Rats via (1)H NMR-Based Metabolomics Approach

Abu Bakar Sajak A, Mediani A, Maulidiani, Ismail A, Abas F

Appl Biochem Biotechnol, 2017 Jun;182(2):653-668.
PMID: 27995574 DOI: 10.1007/s12010-016-2352-9

Diabetes mellitus (DM) is considered as a complex metabolic disease because it affects the metabolism of glucose and other metabolites. Although many diabetes studies have been conducted in animal models throughout the years, the pathogenesis of this disease, especially between lean diabetes (ND + STZ) and obese diabetes (OB + STZ), is still not fully understood. In this study, the urine from ND + STZ, OB + STZ, lean/control (ND), and OB + STZ rats were collected and compared by using (1)H NMR metabolomics. The results from multivariate data analysis (MVDA) showed that the diabetic groups (ND + STZ and OB + STZ) have similarities and dissimilarities for a certain level of metabolites. Differences between ND + STZ and OB + STZ were particularly noticeable in the synthesis of ketone bodies, branched-chain amino acid (BCAA), and sensitivity towards the oral T2DM diabetes drug metformin. This finding suggests that the ND + STZ group was more similar to the T1DM model and OB + STZ to the T2DM model. In addition, we also managed to identify several pathways and metabolism aspects shared by obese (OB) and OB + STZ. The results from this study are useful in developing drug target-based research as they can increase understanding regarding the cause and effect of DM.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods
NMR metabolomics for evaluating passage number and harvesting effects on mammalian cell metabolome

Abdul-Hamid NA, Abas F, Maulidiani M, Ismail IS, Tham CL, Swarup S, et al.

Anal Biochem, 2019 07 01;576:20-32.
PMID: 30970239 DOI: 10.1016/j.ab.2019.04.001

The variation in the extracellular metabolites of RAW 264.7 cells obtained from different passage numbers (passage 9, 12 and 14) was examined. The impact of different harvesting protocols (trypsinization and scraping) on recovery of intracellular metabolites was then assessed. The similarity and variation in the cell metabolome was investigated using 1H NMR metabolic profiling modeled using multivariate data analysis. The characterization and quantification of metabolites was performed to determine the passage-related and harvesting-dependent effects on impacted metabolic networks. The trypsinized RAW cells from lower passages gave higher intensities of most identified metabolites, including asparagine, serine and tryptophan. Principal component analysis revealed variation between cells from different passages and harvesting methods, as indicated by the formation of clusters in score plot. Analysis of S-plots revealed metabolites that acted as biomarkers in discriminating cells from different passages including acetate, serine, lactate and choline. Meanwhile lactate, glutamine and pyruvate served as biomarkers for differentiating trypsinized and scraped cells. In passage-dependent effects, glycolysis and TCA cycle were influential, whereas glycerophospholipid metabolism was affected by the harvesting method. Overall, it is proposed that typsinized RAW cells from lower passage numbers are more appropriate when conducting experiments related to NMR metabolomics.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods*
Plasma Metabolites as Predictors of Warfarin Outcome in Atrial Fibrillation

Bawadikji AA, Teh CH, Sheikh Abdul Kader MAB, Abdul Wahab MJB, Syed Sulaiman SA, Ibrahim B

Am J Cardiovasc Drugs, 2020 Apr;20(2):169-177.
PMID: 31435902 DOI: 10.1007/s40256-019-00364-2

BACKGROUND: Warfarin is prescribed as an oral anticoagulant to treat/prevent thromboembolism in conditions such as atrial fibrillation. As there is a narrow therapeutic window, treatment with warfarin is challenging. Pharmacometabonomics using nuclear magnetic resonance (NMR) spectroscopy may provide novel techniques for the identification of novel biomarkers of warfarin.
PURPOSE: The aim was to determine the metabolic fingerprint that predicts warfarin response based on the international normalized ratio (INR) in patients who are already receiving warfarin (phase I: identification) and to ascertain the metabolic fingerprint that discriminates stable from unstable INR in patients starting treatment with warfarin (phase II: validation).
EXPERIMENTAL APPROACH: A total of 94 blood samples were collected for phase I: 44 patients with stable INR and 50 with unstable INR. Meanwhile, 23 samples were collected for phase II: nine patients with stable INR and 14 with unstable INR. Data analysis was performed using multivariate analysis including principal component analysis and partial least square-discriminate analysis (PLS-DA), followed by univariate and multivariate logistic regression (MVLR) to develop a model to identify unstable INR biomarkers.
KEY RESULTS: For phase I, the PLS-DA model showed the following results: sensitivity 93.18%, specificity 91.49% and accuracy 92.31%. In the MVLR analysis of phase I, ten regions were associated with unstable INR. For phase II, the PLS-DA model showed the following results: sensitivity 66.67%, specificity 61.54% and accuracy 63.64%.
CONCLUSIONS AND IMPLICATIONS: We have shown that the pharmacometabonomics technique was able to differentiate between unstable and stable INR with good accuracy. NMR-based pharmacometabonomics has the potential to identify novel biomarkers in plasma, which can be useful in individualizing treatment and controlling warfarin side effects, thus, minimizing undesirable effects in the future.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods
Metabolomics and Lipidomics of Ischemic Stroke

Au A

Adv Clin Chem, 2018 03 08;85:31-69.
PMID: 29655461 DOI: 10.1016/bs.acc.2018.02.002

Ischemic stroke is a sudden loss of brain function due to the reduction of blood flow. Brain tissues cease to function with subsequent activation of the ischemic cascade. Metabolomics and lipidomics are modern disciplines that characterize the metabolites and lipid components of a biological system, respectively. Because the pathogenesis of ischemic stroke is heterogeneous and multifactorial, it is crucial to establish comprehensive metabolomic and lipidomic approaches to elucidate these alterations in this disease. Fortunately, metabolomic and lipidomic studies have the distinct advantages of identifying tissue/mechanism-specific biomarkers, predicting treatment and clinical outcome, and improving our understanding of the pathophysiologic basis of disease states. Therefore, recent applications of these analytical approaches in the early diagnosis of ischemic stroke were discussed. In addition, the emerging roles of metabolomics and lipidomics on ischemic stroke were summarized, in order to gain new insights into the mechanisms underlying ischemic stroke and in the search for novel metabolite biomarkers and their related pathways.

Matched MeSH terms: Magnetic Resonance Spectroscopy/methods
Multinuclear MR and multilevel data processing: an insight into morphologic assessment of in vivo knee articular cartilage

Hani AF, Kumar D, Malik AS, Walter N, Razak R, Kiflie A

Acad Radiol, 2015 Jan;22(1):93-104.
PMID: 25481518 DOI: 10.1016/j.acra.2014.08.008

Quantitative assessment of knee articular cartilage (AC) morphology using magnetic resonance (MR) imaging requires an accurate segmentation and 3D reconstruction. However, automatic AC segmentation and 3D reconstruction from hydrogen-based MR images alone is challenging because of inhomogeneous intensities, shape irregularity, and low contrast existing in the cartilage region. Thus, the objective of this research was to provide an insight into morphologic assessment of AC using multilevel data processing of multinuclear ((23)Na and (1)H) MR knee images.

Matched MeSH terms: Proton Magnetic Resonance Spectroscopy/methods*