{"id":"1c25e8b4-1bdf-507b-ba2c-3f4faff0a461","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:c-high-oral-dose-calcium-oxalate-index","predicate":"increases_calcium_oxalate_risk_index_in_responders","statement":"The responder subset had a Tiselius Risk Index of 1.10 with versus 0.76 without supplementation.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"e773e5ee-b24a-5df3-93de-cd9d2cdb9fd0","mechanism_event_label":"Their urine measurements shifted toward a higher calculated calcium oxalate stone risk.","subject":{"id":"2047867f-9872-53b2-a553-71c911d0695b","slug":"ascorbic-acid","display_name":"L-Ascorbic acid","entity_type_key":"small_molecule"},"object":{"id":"1438d2e7-cbdb-52aa-9041-0f9944670491","slug":"tiselius-calcium-oxalate-risk-index","display_name":"Tiselius calcium oxalate risk index","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"e773e5ee-b24a-5df3-93de-cd9d2cdb9fd0","stable_key":"cb568d28-484a-5c2e-9fcc-2d780358e514:c-high-oral-dose-calcium-oxalate-index-event","event_type":"observed_intervention","label":"Their urine measurements shifted toward a higher calculated calcium oxalate stone risk.","description":"The responder subset had a Tiselius Risk Index of 1.10 with versus 0.76 without supplementation.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"8e2a5a1f-cd49-5f28-8611-325266fb78a6","slug":"calcium","display_name":"Calcium","entity_type_key":"nutrient_element"},"role":"connected_mineral","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"9c8d2b72-517d-5bb6-8589-cabd98267f65","slug":"oxalate","display_name":"Oxalate","entity_type_key":"ion"},"role":"connected_metabolite","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"2047867f-9872-53b2-a553-71c911d0695b","slug":"ascorbic-acid","display_name":"L-Ascorbic acid","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"1438d2e7-cbdb-52aa-9041-0f9944670491","slug":"tiselius-calcium-oxalate-risk-index","display_name":"Tiselius calcium oxalate risk index","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"Calcium/oxalate urinary chemistry connects a vitamin metabolite to mineral precipitation risk.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Calculated risk is not observed stone formation; this is distinct from a directly measured calcium oxalate activity product.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin C research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-c","display_name":"Vitamin C","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Their urine measurements shifted toward a higher calculated calcium oxalate stone risk.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human blood or whole-person endpoints","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"da2202f7-a0f6-5564-8950-68f49df33fee","evidence_kind":"source_excerpt","locator":"Lines 1682-1693","start_line":1682,"end_line":1693,"excerpt":"### c-high-oral-dose-calcium-oxalate-index\nThe responder subset had a Tiselius Risk Index of 1.10 with versus 0.76 without supplementation.\nCondition category: normal\nnutrient_topic: Vitamin C research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Their urine measurements shifted toward a higher calculated calcium oxalate stone risk.\norganism: Homo sapiens\ntissue_or_cell_type: Human blood or whole-person endpoints\nexperimental_model: Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.\nlimitations: Calculated risk is not observed stone formation; this is distinct from a directly measured calcium oxalate activity product.\nexposure: Ascorbic acid 1000 mg twice daily for six days versus no supplement for six days; 13C2 oxalate challenge after adaptation.\ncross_nutrient: Calcium/oxalate urinary chemistry connects a vitamin metabolite to mineral precipitation risk.\n[c-massey2005] Ascorbate increases human oxaluria and kidney stone risk (2005). https://pubmed.ncbi.nlm.nih.gov/15987848/ DOI: 10.1093/jn/135.7.1673","model_system":"Randomized controlled-diet crossover study: 29 calcium stone formers and 19 non-stone formers.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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