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The tissue survey is in rat; the human arm is the demonstration that inversion is one-way.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Ibuprofen research collection; topical membership is not evidence of a direct clinical effect, and the racemate is recorded separately from each of its two enantiomers.","comparator":null,"unit":null,"notes":"","entity":{"slug":"ibuprofen","display_name":"Ibuprofen","entity_type_key":"drug"}},{"dimension":"organism","value_text":"Human and rat","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"An enzyme flips the activated form from one hand to the other, mostly in the liver and kidney.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[ibu-p1680979] Metabolic inversion of stereoisomeric ibuprofen in man. (1991). https://pubmed.ncbi.nlm.nih.gov/1680979/","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Liver and kidney","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"c4e9da92-dcbb-51ce-9198-54012e13c57c","evidence_kind":"source_excerpt","locator":"Lines 97-108","start_line":97,"end_line":108,"excerpt":"### ibu-epimerase-acts-on-the-thioester\nIbuprofen epimerization in humans is virtually irreversible from R to S, and 2-arylpropionyl-CoA epimerase readily converts R-ibuprofen-CoA into its S counterpart in active subcellular hepatic preparations, with examination of epimerase activity across tissues indicating that this metabolism occurs mainly in liver and kidney; reduced renal clearance together with metabolic bioactivation from inversion may raise plasma levels of the active species unpredictably.\nCondition category: normal\nnutrient_topic: Ibuprofen research collection; topical membership is not evidence of a direct clinical effect, and the racemate is recorded separately from each of its two enantiomers.\nplain_language: An enzyme flips the activated form from one hand to the other, mostly in the liver and kidney.\norganism: Human and rat\ntissue_or_cell_type: Liver and kidney\nexperimental_model: Enantioselective high performance liquid chromatography in humans with active subcellular hepatic preparations from rats\nlimitations: Establishes the epimerase step directly on the thioester. The tissue survey is in rat; the human arm is the demonstration that inversion is one-way.\nexposure: Racemic and single-enantiomer ibuprofen, with R-ibuprofen-CoA applied to subcellular fractions\nevidence_span: {\"source_cache\": \"artifacts/ibuprofen-research/1680979.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"4888135fd1db1817c370825ee8a1435b7654e68af33912093c725fe7041341cc\", \"start_char\": 0, \"end_char\": 1119, \"text_sha256\": \"4888135fd1db1817c370825ee8a1435b7654e68af33912093c725fe7041341cc\"}\n[ibu-p1680979] Metabolic inversion of stereoisomeric ibuprofen in man. (1991). https://pubmed.ncbi.nlm.nih.gov/1680979/","model_system":"Enantioselective high performance liquid chromatography in humans with active subcellular hepatic preparations from rats","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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