X-Message-Number: 29336 From: "Basie" <> Subject: Observation and identification of metabolites emerging during... Date: Mon, 19 Mar 2007 17:41:28 -0500 1: Magn Reson Med. 2002 Nov;48(5):915-20. Links Observation and identification of metabolites emerging during postmortem decomposition of brain tissue by means of in situ 1H-magnetic resonance spectroscopy.Ith M, Bigler P, Scheurer E, Kreis R, Hofmann L, Dirnhofer R, Boesch C. Department of Clinical Research (MR Spectroscopy and Methodology), University Bern, Switzerland. Postmortem decomposition of brain tissue was investigated by (1)H-magnetic resonance spectroscopy (MRS) in a sheep head model and selected human cases. Aiming at the eventual estimation of postmortem intervals in forensic medicine, this study focuses on the characterization and identification of newly observed metabolites. In situ single-voxel (1)H-MRS at 1.5 T was complemented by multidimensional homo- and heteronuclear high-resolution NMR spectroscopy of an extract of sheep brain tissue. The inclusion of spectra of model solutions in the program LC Model confirmed the assignments in situ. The first postmortem phase was characterized mainly by changes in the concentrations of metabolites usually observed in vivo and by the appearance of previously reported decay products. About 3 days postmortem, new metabolites, including free trimethylammonium, propionate, butyrate, and iso-butyrate, started to appear in situ. Since the observed metabolites and the time course is comparable in sheep and human brain tissue, the model system seems to be appropriate. Copyright 2002 Wiley-Liss, Inc. PMID: 12418008 [PubMed - indexed for MEDLINE] Related LinksStatistical evaluation of time-dependent metabolite concentrations: estimation of post-mortem intervals based on in situ 1H-MRS of the brain. [NMR Biomed. 2005] PMID: 15578674 Estimation of postmortem metabolic changes in porcine brain tissue using 1H-MR spectroscopy--preliminary results. [Int J Legal Med. 2005] PMID: 15578198 Dynamic high-resolution 1H and 31P NMR spectroscopy and 1H T2 measurements in postmortem rabbit muscles using slow magic angle spinning. [J Agric Food Chem. 2004] PMID: 15113176 Postmortem metabolic and morphologic alterations of the dog brain thalamus with use of in vivo 1H magnetic resonance spectroscopy and electron microscopy. [Invest Radiol. 1995] PMID: 7558730 Ex vivo proton MR spectroscopy (1H-MRS) for evaluation of human gastric carcinoma. [Magn Reson Imaging. 2004] PMID: 15234456 See all Related Articles... Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=29336