{"id":"5b6b244d-28e1-5325-88c1-b9c987293607","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-pancreatic-competitor-rescue","predicate":"restores-in-tested-patients","statement":"In three patients with pancreatic insufficiency, oral cobinamide 100 nmol corrected malabsorption of 0.4 nmol radiocobalamin in Schilling tests, comparably to trypsin.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"08fb8f4f-72ca-580b-91b6-df8028618233","mechanism_event_label":"Blocking haptocorrin competition restored tracer absorption in three patients.","subject":{"id":"6611b55d-f95b-5d90-baa6-ae5a5697df36","slug":"cobinamide","display_name":"Cobinamide","entity_type_key":"small_molecule"},"object":{"id":"8c0f397a-9cad-554f-ac5b-bb51bf1be2ac","slug":"intestinal-cobalamin-absorption","display_name":"Intestinal cobalamin absorption","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"08fb8f4f-72ca-580b-91b6-df8028618233","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abs-pancreatic-competitor-rescue-event","event_type":"biochemical_relationship","label":"Blocking haptocorrin competition restored tracer absorption in three patients.","description":"In three patients with pancreatic insufficiency, oral cobinamide 100 nmol corrected malabsorption of 0.4 nmol radiocobalamin in Schilling tests, comparably to trypsin.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"b6d9b937-895d-5e0a-8cc5-0454a0b7d373","slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"},"role":"nutrient","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"21f01bdf-1da9-59c3-af35-c67281e89dd4","slug":"tcn1","display_name":"Human haptocorrin / TCN1","entity_type_key":"protein"},"role":"competition-target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"490161eb-b7f8-56b6-82bc-77c8c0bdc1ca","slug":"gif","display_name":"Human gastric intrinsic factor / GIF","entity_type_key":"protein"},"role":"acceptor","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"6611b55d-f95b-5d90-baa6-ae5a5697df36","slug":"cobinamide","display_name":"Cobinamide","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"8c0f397a-9cad-554f-ac5b-bb51bf1be2ac","slug":"intestinal-cobalamin-absorption","display_name":"Intestinal cobalamin absorption","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Three human pancreatic-insufficiency patients and parallel human binding assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Cobinamide competitor during Schilling test","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Small physiological intervention; cobinamide is an experimental analogue, not B12 nutrition. The absorption defect was pancreatic machinery impairment.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Blocking haptocorrin competition restored tracer absorption in three patients.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[allen-1978-cobinamide] Correction of cobalamin malabsorption in pancreatic insufficiency with a cobalamin analogue that binds with high affinity to R protein but not to intrinsic factor. In vivo evidence that a failure to partially degrade R protein is responsible for cobalamin malabsorption in pancreatic insufficiency. (1978). https://pubmed.ncbi.nlm.nih.gov/659618/ DOI: 10.1172/jci109083","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Intestinal absorption and urinary radiotracer recovery","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"9dea6546-2d33-5a4b-8a0a-207c8c6cae9b","evidence_kind":"source_excerpt","locator":"Lines 205-216","start_line":205,"end_line":216,"excerpt":"### b12-abs-pancreatic-competitor-rescue\nIn three patients with pancreatic insufficiency, oral cobinamide 100 nmol corrected malabsorption of 0.4 nmol radiocobalamin in Schilling tests, comparably to trypsin.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Blocking haptocorrin competition restored tracer absorption in three patients.\norganism: Homo sapiens\ntissue_or_cell_type: Intestinal absorption and urinary radiotracer recovery\nexperimental_model: Three human pancreatic-insufficiency patients and parallel human binding assays\nlimitations: Small physiological intervention; cobinamide is an experimental analogue, not B12 nutrition. The absorption defect was pancreatic machinery impairment.\nexposure: Cobinamide competitor during Schilling test\ncross_nutrient: false\n[allen-1978-cobinamide] Correction of cobalamin malabsorption in pancreatic insufficiency with a cobalamin analogue that binds with high affinity to R protein but not to intrinsic factor. In vivo evidence that a failure to partially degrade R protein is responsible for cobalamin malabsorption in pancreatic insufficiency. (1978). https://pubmed.ncbi.nlm.nih.gov/659618/ DOI: 10.1172/jci109083","model_system":"Three human pancreatic-insufficiency patients and parallel human binding assays","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [allen-1978-cobinamide] Correction of cobalamin malabsorption in pancreatic insufficiency with a cobalamin analogue that binds with high affinity to R protein but not to intrinsic factor. In vivo evidence that a failure to partially degrade R protein is responsible for cobalamin malabsorption in pancreatic insufficiency. (1978). https://pubmed.ncbi.nlm.nih.gov/659618/ DOI: 10.1172/jci109083","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"73145023-2982-5848-aff2-8d8875d6b9c5","stable_key":"import-7fc92b9e-9cbf-556e-8719-6b5244625250","title":"Vitamin B12: mechanisms, deficiency and nutrient interactions (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":"ad5b3a51d36e856aa7fdfd1cc23f690b094689bad87d28e1a621a54675a01c92","revision_id":"118bd616-0c13-549f-bfeb-bc439715b89c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}