{"id":"7cb0cbb7-f542-5fc3-8609-73ae883e5f2d","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-urinary-qa-ratio","predicate":"predicts_in_cohort","statement":"In critically ill humans, a higher urinary quinolinate/tryptophan ratio predicted acute kidney injury and adverse outcomes; reduced QPRT was a mechanistic interpretation informed by mouse work.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"14d63fcf-5fb6-5db7-a594-46796404286e","mechanism_event_label":"A urine ratio was a risk marker, not a direct human enzyme measurement.","subject":{"id":"73c173a6-1270-5dfc-a648-772ae3893d4c","slug":"human-urinary-quinolinate-tryptophan-ratio","display_name":"Human urinary quinolinate-to-tryptophan ratio","entity_type_key":"cellular_process"},"object":{"id":"07d188a0-bacc-5438-b794-4e0d6c23da2e","slug":"human-acute-kidney-injury-risk","display_name":"Human acute kidney injury risk","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"14d63fcf-5fb6-5db7-a594-46796404286e","stable_key":"584c58f5-ab9f-53f3-97a9-55783db943b0:tryptophan-urinary-qa-ratio-event","event_type":"observed_relationship","label":"A urine ratio was a risk marker, not a direct human enzyme measurement.","description":"In critically ill humans, a higher urinary quinolinate/tryptophan ratio predicted acute kidney injury and adverse outcomes; 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