{"id":"996b9d60-3ea3-50ea-b176-bc6bb49e6dc7","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:normal-serum-calcium-does-not-establish-sufficiency","predicate":"does_not_establish","statement":"Mice with intestinal Vdr deletion maintained serum calcium despite calcium malabsorption and impaired skeletal mineral storage.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"9f15ebcb-4baf-5a2e-9df9-b25821746bc0","mechanism_event_label":"Normal blood calcium can coexist with inadequate skeletal supply.","subject":{"id":"068b1eb6-c8bf-59d3-98a0-df623ad01b52","slug":"serum-calcium-concentration","display_name":"Serum calcium concentration","entity_type_key":"cellular_process"},"object":{"id":"a3041bd4-e52c-513e-bca5-0532cd0bc943","slug":"calcium-nutritional-status","display_name":"Calcium nutritional status","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"9f15ebcb-4baf-5a2e-9df9-b25821746bc0","stable_key":"434e1e27-eb90-583a-956b-62472726ffba:normal-serum-calcium-does-not-establish-sufficiency-event","event_type":"biomarker","label":"Normal blood calcium can coexist with inadequate skeletal supply.","description":"Mice with intestinal Vdr deletion maintained serum calcium despite calcium malabsorption and impaired skeletal mineral storage.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d725020b-bacc-5e90-b370-cda246025c91","slug":"vdr","display_name":"Vitamin D receptor / VDR","entity_type_key":"protein"},"role":"impaired_intestinal_machinery","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"e359bc15-e675-5d83-b0fe-1d70814e130b","slug":"calcium-ion","display_name":"Calcium ion","entity_type_key":"ion"},"role":"regulated_ion","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"068b1eb6-c8bf-59d3-98a0-df623ad01b52","slug":"serum-calcium-concentration","display_name":"Serum calcium concentration","entity_type_key":"cellular_process"},"role":"measured_marker","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"da1bbfb0-d536-5b3b-aa99-994620d9d07d","slug":"bone-mineralization","display_name":"Bone mineralization","entity_type_key":"cellular_process"},"role":"affected_process","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"a3041bd4-e52c-513e-bca5-0532cd0bc943","slug":"calcium-nutritional-status","display_name":"Calcium nutritional status","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; 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unverified.","entity":null}],"evidence":[{"id":"2ede55d0-8586-5512-8bff-b429df5fb669","evidence_kind":"source_excerpt","locator":"Lines 337-347","start_line":337,"end_line":347,"excerpt":"### normal-serum-calcium-does-not-establish-sufficiency\nMice with intestinal Vdr deletion maintained serum calcium despite calcium malabsorption and impaired skeletal mineral storage.\nCondition category: biomarker_context\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Normal blood calcium can coexist with inadequate skeletal supply.\norganism: Mus musculus\ntissue_or_cell_type: Blood, intestine and skeleton\nexperimental_model: Intestinal and osteoblast Vdr deletion, low-calcium diets, and skeletal assays in growing mice\nlimitations: Growing-mouse genetic model; not a validated human dietary diagnostic.\nresearch_relationship_category: biomarker\n[lieben2012] Normocalcemia is maintained in mice under conditions of calcium malabsorption by vitamin D-induced inhibition of bone mineralization (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3336970/ DOI: 10.1172/JCI45890","model_system":"Intestinal and osteoblast Vdr deletion, low-calcium diets, and skeletal assays in growing mice","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [lieben2012] Normocalcemia is maintained in mice under conditions of calcium malabsorption by vitamin D-induced inhibition of bone mineralization (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3336970/ DOI: 10.1172/JCI45890","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"3c083fa0-59c6-50e9-af42-678d0e3c1006","stable_key":"import-434e1e27-eb90-583a-956b-62472726ffba","title":"Calcium: mechanism-first literature curation (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"965c934d6b147f2b62f8d45ce6d7a87681a600bfe5c46a585b4704889afd3fc1","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[{"id":"21a03b7b-8fef-516e-8a9f-16077c7f30a9","title":"Circulating calcium and whole-body adequacy answer different questions","kind":"qualification","status":"qualified","why":"Total and ionized measurements can disagree, and normocalcemia can persist despite malabsorption.","resolution":"Curation interpretation: Preserve marker identity and clinical/model context; a blood value alone cannot establish dietary adequacy.","created_at":"2026-09-17 08:08:54","record_type":"qualification","display_label":"Source qualification","record_url":"/corrections/21a03b7b-8fef-516e-8a9f-16077c7f30a9","sides":[{"conflict_id":"21a03b7b-8fef-516e-8a9f-16077c7f30a9","ordinal":0,"label":"Total and ionized calcium are different measurements.","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","start_line":313,"end_line":323,"quote":"### total-calcium-imperfect-ionized-proxy-ckd\nIn 691 patients with stage 3-5 CKD, total calcium showed only fair agreement with ionized-calcium classification.\nCondition category: biomarker_context\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Total and ionized calcium are different measurements.\norganism: Homo sapiens\ntissue_or_cell_type: Blood\nexperimental_model: 691 patients with stage 3-5 chronic kidney disease; paired calcium measurements\nlimitations: CKD cohort; albumin correction did not improve prediction.\nresearch_relationship_category: biomarker\n[gauci2008] Pitfalls of measuring total blood calcium in patients with CKD (2008). https://pmc.ncbi.nlm.nih.gov/articles/PMC2488254/ DOI: 10.1681/ASN.2007040449","source_key":"import-434e1e27-eb90-583a-956b-62472726ffba","source_title":"Calcium: mechanism-first literature curation (2026-09-17)","claim_ids":["7394a38c-bc0f-5922-9be3-8cf03e6cb48a"]},{"conflict_id":"21a03b7b-8fef-516e-8a9f-16077c7f30a9","ordinal":1,"label":"Calculated correction is not a direct ionized-calcium test.","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","start_line":325,"end_line":335,"quote":"### albumin-adjustment-calcium-misclassification\nCommon albumin-adjusted calcium formulas generally classified ionized calcium no better than unadjusted total calcium in a 22,658-adult comparison.\nCondition category: biomarker_context\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Calculated correction is not a direct ionized-calcium test.\norganism: Homo sapiens\ntissue_or_cell_type: Blood\nexperimental_model: Cross-sectional comparison of paired laboratory tests in 22,658 adults in Alberta\nlimitations: Cross-sectional tested population; formulas and patient context differ.\nresearch_relationship_category: biomarker\n[desgagnes2025] Use of Albumin-Adjusted Calcium Measurements in Clinical Practice (2025). https://pmc.ncbi.nlm.nih.gov/articles/PMC11751745/ DOI: 10.1001/jamanetworkopen.2024.55251","source_key":"import-434e1e27-eb90-583a-956b-62472726ffba","source_title":"Calcium: mechanism-first literature curation (2026-09-17)","claim_ids":["614e43b7-8c68-56a2-9b6b-913aeba8f0d6"]},{"conflict_id":"21a03b7b-8fef-516e-8a9f-16077c7f30a9","ordinal":2,"label":"Normal blood calcium can coexist with inadequate skeletal supply.","revision_id":"543ec48b-4f70-5197-9d76-f5a3c443664c","start_line":337,"end_line":347,"quote":"### normal-serum-calcium-does-not-establish-sufficiency\nMice with intestinal Vdr deletion maintained serum calcium despite calcium malabsorption and impaired skeletal mineral storage.\nCondition category: biomarker_context\nnutrient_topic: Calcium research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Normal blood calcium can coexist with inadequate skeletal supply.\norganism: Mus musculus\ntissue_or_cell_type: Blood, intestine and skeleton\nexperimental_model: Intestinal and osteoblast Vdr deletion, low-calcium diets, and skeletal assays in growing mice\nlimitations: Growing-mouse genetic model; not a validated human dietary diagnostic.\nresearch_relationship_category: biomarker\n[lieben2012] Normocalcemia is maintained in mice under conditions of calcium malabsorption by vitamin D-induced inhibition of bone mineralization (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC3336970/ DOI: 10.1172/JCI45890","source_key":"import-434e1e27-eb90-583a-956b-62472726ffba","source_title":"Calcium: mechanism-first literature curation (2026-09-17)","claim_ids":["996b9d60-3ea3-50ea-b176-bc6bb49e6dc7"]}]}],"research":null}