{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T01:38:59Z","timestamp":1773020339948,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,22]],"date-time":"2022-07-22T00:00:00Z","timestamp":1658448000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Chang Gung Foundation","award":["BMRPF63"],"award-info":[{"award-number":["BMRPF63"]}]},{"name":"Chang Gung Foundation","award":["CMRPG3M0731"],"award-info":[{"award-number":["CMRPG3M0731"]}]},{"name":"Chang Gung Foundation","award":["CMRPG3G1211-3"],"award-info":[{"award-number":["CMRPG3G1211-3"]}]},{"name":"Chang Gung Foundation","award":["CLRPG3K0023"],"award-info":[{"award-number":["CLRPG3K0023"]}]},{"name":"Chang Gung Foundation","award":["MOST106-2218-E-182-004"],"award-info":[{"award-number":["MOST106-2218-E-182-004"]}]},{"name":"Chang Gung Foundation","award":["MOST 110-2628-B-182A-018"],"award-info":[{"award-number":["MOST 110-2628-B-182A-018"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["BMRPF63"],"award-info":[{"award-number":["BMRPF63"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["CMRPG3M0731"],"award-info":[{"award-number":["CMRPG3M0731"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["CMRPG3G1211-3"],"award-info":[{"award-number":["CMRPG3G1211-3"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["CLRPG3K0023"],"award-info":[{"award-number":["CLRPG3K0023"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["MOST106-2218-E-182-004"],"award-info":[{"award-number":["MOST106-2218-E-182-004"]}]},{"name":"Ministry of Science and Technology, Taiwan","award":["MOST 110-2628-B-182A-018"],"award-info":[{"award-number":["MOST 110-2628-B-182A-018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Hyperpolarized carbon-13 MRI has the advantage of allowing the study of glycolytic flow in vivo or in vitro dynamically in real-time. The apparent exchange rate constant of a metabolite dynamic signal reflects the metabolite changes of a disease. Downstream metabolites can have a low signal-to-noise ratio (SNR), causing apparent exchange rate constant inconsistencies. Thus, we developed a method that estimates a more accurate metabolite signal. This method utilizes a kinetic model and background noise to estimate metabolite signals. Simulations and in vitro studies with photon-irradiated and control groups were used to evaluate the procedure. Simulated and in vitro exchange rate constants estimated using our method were compared with the raw signal values. In vitro data were also compared to the Area-Under-Curve (AUC) of the cell medium in 13C Nuclear Magnetic Resonance (NMR). In the simulations and in vitro experiments, our technique minimized metabolite signal fluctuations and maintained reliable apparent exchange rate constants. In addition, the apparent exchange rate constants of the metabolites showed differences between the irradiation and control groups after using our method. Comparing the in vitro results obtained using our method and NMR, both solutions showed consistency when uncertainty was considered, demonstrating that our method can accurately measure metabolite signals and show how glycolytic flow changes. The method enhanced the signals of the metabolites and clarified the metabolic phenotyping of tumor cells, which could benefit personalized health care and patient stratification in the future.<\/jats:p>","DOI":"10.3390\/s22155480","type":"journal-article","created":{"date-parts":[[2022,7,25]],"date-time":"2022-07-25T04:52:47Z","timestamp":1658724767000},"page":"5480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Developing a Method to Estimate the Downstream Metabolite Signals from Hyperpolarized [1-13C]Pyruvate"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9475-5169","authenticated-orcid":false,"given":"Ching-Yi","family":"Hsieh","sequence":"first","affiliation":[{"name":"Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University, Taoyuan 333, Taiwan"},{"name":"Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan"}]},{"given":"Cheng-Hsuan","family":"Sung","sequence":"additional","affiliation":[{"name":"Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University, Taoyuan 333, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2910-1393","authenticated-orcid":false,"given":"Yi-Liang (Eric)","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology and Proton Therapy Center, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0148-9488","authenticated-orcid":false,"given":"Ying-Chieh","family":"Lai","sequence":"additional","affiliation":[{"name":"Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4677-9000","authenticated-orcid":false,"given":"Kuan-Ying","family":"Lu","sequence":"additional","affiliation":[{"name":"Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan"},{"name":"Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7246-1058","authenticated-orcid":false,"given":"Gigin","family":"Lin","sequence":"additional","affiliation":[{"name":"Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan"},{"name":"Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1046\/j.1432-1327.1998.2540096.x","article-title":"Carbon-flux distribution in the central metabolic pathways of Corynebacterium glutamicum during growth on fructose","volume":"254","author":"Dominguez","year":"1998","journal-title":"Eur. 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