Sensitivity-improved versions of two-dimensional (2D) C-H HSQC (heteronuclear single quantum coherence) and HSQC-TOCSY (HSQC-total correlation spectroscopy) NMR experiments optimized for small biological molecules and their complex mixtures encountered in metabolomics are presented that preserve the magnetization of H spins not directly attached to C spins. This allows (i) the application of rapid acquisition techniques to substantially shorten measurement time and (ii) their incorporation into supersequences (NOAH-NMR by ordered acquisition using H detection) for the compact acquisition of multiple 2D NMR data sets with significant gains in sensitivity, resolution, and/or time. The new pulse sequences, which are demonstrated for both metabolite model mixtures and mouse urine, offer an attractive approach for the efficient measurement of multiple 2D NMR spectra (HSQCsi and/or HSQCsi-TOCSY and TOCSY) of metabolomics samples in a single experiment for the accurate and comprehensive identification and quantitation of metabolites. These new methods bring to bear the advantages of 2D NMR to metabolomics studies with larger cohorts of samples.
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http://dx.doi.org/10.1021/acs.analchem.0c05205 | DOI Listing |
Methods Mol Biol
January 2025
Center for Environmental Measurement and Modeling, Environmental Protection Agency, Athens, GA, USA.
Metabolic profiling (untargeted metabolomics) aims for a global unbiased analysis of metabolites in a cell or biological system. It remains a highly useful research tool used across various analytical platforms. Incremental improvements across multiple steps in the analytical process may have large consequences for the end quality of the data.
View Article and Find Full Text PDFJ Neurol
January 2025
Department of Neurology, Clinic of Optic Neuritis and Danish Multiple Sclerosis Center, Rigshospitalet-Glostrup, Valdemar Hansens Vej 13, 2600, Glostrup, Denmark.
Background: Although optic neuritis (ON) is common in multiple sclerosis (MS), lesions of the optic nerve are not included as an anatomical substrate for dissemination in space and time (DIS and DIT).
Objective: To assess the increase in sensitivity of including MRI lesions of the optic nerve for the diagnosis of MS in patients with ON.
Methods: We included patients consecutively referred with first time, monosymptomatic ON, with no known cause of the ON, who underwent orbital MRI including fat suppressed T2 and T1-sequences with and without gadolinium contrast.
Eur Radiol Exp
January 2025
St Vincent's University Hospital, Dublin, Ireland.
Background: The large language model ChatGPT can now accept image input with the GPT4-vision (GPT4V) version. We aimed to compare the performance of GPT4V to pretrained U-Net and vision transformer (ViT) models for the identification of the progression of multiple sclerosis (MS) on magnetic resonance imaging (MRI).
Methods: Paired coregistered MR images with and without progression were provided as input to ChatGPT4V in a zero-shot experiment to identify radiologic progression.
J Neurol
January 2025
NMR Research Unit, Queen Square MS Centre, Department of Neuroinflammation, Faculty of Brain Sciences, UCL Queen Square Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
Cognitive impairment (CI) in multiple sclerosis (MS) is only partially explained by whole-brain volume measures, but independent component analysis (ICA) can extract regional patterns of damage in grey matter (GM) or white matter (WM) that have proven more closely associated with CI. Pathology in GM and WM occurs in parallel, and so patterns can span both. This study assessed whether joint-ICA of GM and WM features better explained cognitive function compared to single-tissue ICA.
View Article and Find Full Text PDFJ Neurol
January 2025
Department of Neurology, School of Medical Sciences, University of Campinas-UNICAMP, Universitaria "Zeferino Vaz", Rua Tessália Vieira de Camargo, 126. Cidade, Campinas, SP, 13083-887, Brazil.
Background: Skeletal and cardiac muscle damage have been increasingly recognized in female carriers of DMD pathogenic variants (DMDc). Little is known about cognitive impairment in these women or whether they have structural brain damage.
Objective: To characterize the cognitive profile in a Brazilian cohort of DMDc and determine whether they have structural brain abnormalities using multimodal MRI.
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