{"id":"4ac9cb8e-2499-524a-8210-a56cbf0fbec8","stable_key":"0ad8610d-d575-5870-b7cd-763a9f750783:copper-human-lowcu-sod-boundary","predicate":"depletion_did_not_show_significant_time_trend_in","statement":"Erythrocyte SOD activity was lower on average during low intake, but did not show a significant time trend across depletion.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"ed5abcf4-4ec0-5b8d-8bcd-746924fe8785","mechanism_event_label":"Not every copper-related marker responded with the same sensitivity.","subject":{"id":"9f0afdde-1ec1-5c8a-bb5e-f3b2b75f67f6","slug":"copper","display_name":"Copper","entity_type_key":"nutrient_element"},"object":{"id":"09fadb77-b222-5d11-b365-077675f16d13","slug":"erythrocyte-cu-zn-sod-activity","display_name":"Erythrocyte copper/zinc superoxide dismutase activity","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"ed5abcf4-4ec0-5b8d-8bcd-746924fe8785","stable_key":"0ad8610d-d575-5870-b7cd-763a9f750783:copper-human-lowcu-sod-boundary-event","event_type":"observed_intervention","label":"Not every copper-related marker responded with the same sensitivity.","description":"Erythrocyte SOD activity was lower on average during low intake, but did not show a significant time trend across depletion.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"9f0afdde-1ec1-5c8a-bb5e-f3b2b75f67f6","slug":"copper","display_name":"Copper","entity_type_key":"nutrient_element"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"09fadb77-b222-5d11-b365-077675f16d13","slug":"erythrocyte-cu-zn-sod-activity","display_name":"Erythrocyte copper/zinc superoxide dismutase activity","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/copper-research/8988916.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"0be30b28f91bce964b969517de4b15eb3ba5905a6f5f1f0a9dc4afa29e9d101b\", \"start_char\": 0, \"end_char\": 1349, \"text_sha256\": \"0be30b28f91bce964b969517de4b15eb3ba5905a6f5f1f0a9dc4afa29e9d101b\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Metabolic-ward depletion and repletion study","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Eleven men: 0.66 mg copper/day for 24 days, 0.38 for 42 days, then 2.49 for 24 days","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Small controlled feeding study; regimen-specific changes are not universal diagnostic thresholds or modern intake recommendations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Copper research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"copper","display_name":"Copper","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human young men","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Not every copper-related marker responded with the same sensitivity.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[copper-p8988916] Copper status of young men consuming a low-copper diet. (1997). https://pubmed.ncbi.nlm.nih.gov/8988916/ DOI: 10.1093/ajcn/65.1.72","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Plasma, urine and erythrocytes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"42c8545f-9c8b-5ebf-b3b4-e983742eada6","evidence_kind":"source_excerpt","locator":"Lines 1352-1363","start_line":1352,"end_line":1363,"excerpt":"### copper-human-lowcu-sod-boundary\nErythrocyte SOD activity was lower on average during low intake, but did not show a significant time trend across depletion.\nCondition category: biomarker_context\nnutrient_topic: Copper research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Not every copper-related marker responded with the same sensitivity.\norganism: Human young men\ntissue_or_cell_type: Plasma, urine and erythrocytes\nexperimental_model: Metabolic-ward depletion and repletion study\nlimitations: Small controlled feeding study; regimen-specific changes are not universal diagnostic thresholds or modern intake recommendations.\nexposure: Eleven men: 0.66 mg copper/day for 24 days, 0.38 for 42 days, then 2.49 for 24 days\nevidence_span: {\"source_cache\": \"artifacts/copper-research/8988916.abstract.txt\", \"locator\": \"Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"0be30b28f91bce964b969517de4b15eb3ba5905a6f5f1f0a9dc4afa29e9d101b\", \"start_char\": 0, \"end_char\": 1349, \"text_sha256\": \"0be30b28f91bce964b969517de4b15eb3ba5905a6f5f1f0a9dc4afa29e9d101b\"}\n[copper-p8988916] Copper status of young men consuming a low-copper diet. 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