{"id":"a1d6758b-0c80-578c-af78-353d26efb073","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:nia-clin-pellagra-lesions","predicate":"prolonged_shortage_associated_with","statement":"The three prolonged corn-diet subjects developed initial pellagra signs between days 50 and 60; lesions differed between individuals, and typical hand dermatitis developed later in two.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"33656a15-621f-5eb8-9bf3-e1172ba4b9ba","mechanism_event_label":"Long enough shortage injured skin and mucosal tissues, but people did not develop the same signs in the same order.","subject":{"id":"dfc664d3-d84d-55ca-afe2-1abbfafd83a7","slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"},"object":{"id":"e191e61f-d646-56db-b20b-59430d415668","slug":"pellagra-clinical-lesions","display_name":"Pellagra clinical lesions","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"33656a15-621f-5eb8-9bf3-e1172ba4b9ba","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:nia-clin-pellagra-lesions-event","event_type":"observed_intervention","label":"Long enough shortage injured skin and mucosal tissues, but people did not develop the same signs in the same order.","description":"The three prolonged corn-diet subjects developed initial pellagra signs between days 50 and 60; lesions differed between individuals, and typical hand dermatitis developed later in two.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"769339cb-213b-559e-acc0-07ed00368b94","slug":"l-tryptophan","display_name":"L-Tryptophan","entity_type_key":"small_molecule"},"role":"co_restricted_precursor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"dfc664d3-d84d-55ca-afe2-1abbfafd83a7","slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"e191e61f-d646-56db-b20b-59430d415668","slug":"pellagra-clinical-lesions","display_name":"Pellagra clinical lesions","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"L-Tryptophan (co_restricted_precursor)","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-clinical-sources/goldsmith1952.txt\", \"locator\": \"Primary full report; exact character range, zero-based and end-exclusive\", \"file_sha256\": \"2d4004fb5985f80c8e44909506e1aa05b6eefd838f4c28102beac30fb3092bc5\", \"start_char\": 13468, \"end_char\": 15488, \"text_sha256\": \"78476c492b7ccdbe08740a06623f5a4856394c368e22b1bfdcdde2bc345e9a36\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Historical metabolic-ward restriction; seven women, with three prolonged corn-diet cases developing pellagra","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Corn diet about 4.7 mg niacin and 190 mg tryptophan/day; other B-vitamin supplements; 40–135 days depending on subject; subsequent niacinamide or DL-tryptophan","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Very small nonrandomized historical experiment. Diets and exposure durations differed; signs were not universal. Nitrogen balance did not prove niacin sufficiency. This does not establish a modern intake threshold or demonstrate a corn toxin.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Niacin research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"niacin","display_name":"Niacin (vitamin B3)","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Long enough shortage injured skin and mucosal tissues, but people did not develop the same signs in the same order.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nia-clin-goldsmith1952] Studies of niacin requirement in man. I. Experimental pellagra in subjects on corn diets low in niacin and tryptophan. (1952). https://pubmed.ncbi.nlm.nih.gov/14938430/ DOI: 10.1172/jci102638","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Skin, oral and intestinal mucosa","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"40235768-c772-59d0-af11-7d24c117a070","evidence_kind":"source_excerpt","locator":"Lines 1191-1203","start_line":1191,"end_line":1203,"excerpt":"### nia-clin-pellagra-lesions\nThe three prolonged corn-diet subjects developed initial pellagra signs between days 50 and 60; lesions differed between individuals, and typical hand dermatitis developed later in two.\nCondition category: nutrient_deficiency\nnutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Long enough shortage injured skin and mucosal tissues, but people did not develop the same signs in the same order.\norganism: Homo sapiens\ntissue_or_cell_type: Skin, oral and intestinal mucosa\nexperimental_model: Historical metabolic-ward restriction; seven women, with three prolonged corn-diet cases developing pellagra\nlimitations: Very small nonrandomized historical experiment. Diets and exposure durations differed; signs were not universal. Nitrogen balance did not prove niacin sufficiency. This does not establish a modern intake threshold or demonstrate a corn toxin.\nexposure: Corn diet about 4.7 mg niacin and 190 mg tryptophan/day; other B-vitamin supplements; 40–135 days depending on subject; subsequent niacinamide or DL-tryptophan\ncross_nutrient: L-Tryptophan (co_restricted_precursor)\nevidence_span: {\"source_cache\": \"artifacts/niacin-clinical-sources/goldsmith1952.txt\", \"locator\": \"Primary full report; exact character range, zero-based and end-exclusive\", \"file_sha256\": \"2d4004fb5985f80c8e44909506e1aa05b6eefd838f4c28102beac30fb3092bc5\", \"start_char\": 13468, \"end_char\": 15488, \"text_sha256\": \"78476c492b7ccdbe08740a06623f5a4856394c368e22b1bfdcdde2bc345e9a36\"}\n[nia-clin-goldsmith1952] Studies of niacin requirement in man. I. Experimental pellagra in subjects on corn diets low in niacin and tryptophan. (1952). https://pubmed.ncbi.nlm.nih.gov/14938430/ DOI: 10.1172/jci102638","model_system":"Historical metabolic-ward restriction; seven women, with three prolonged corn-diet cases developing pellagra","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [nia-clin-goldsmith1952] Studies of niacin requirement in man. I. Experimental pellagra in subjects on corn diets low in niacin and tryptophan. (1952). https://pubmed.ncbi.nlm.nih.gov/14938430/ DOI: 10.1172/jci102638","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"a62b7b5b-786a-57e9-85e9-67c6912a5054","stable_key":"import-a9dd23c6-978a-5755-8bd8-f29bd1fe0cda","title":"Niacin: NAD metabolism, 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":"a8cac59639322f74812ce12eef338c2f6c385c04cc4af6ab511fc7c972f0c2e6","revision_id":"bec8fc45-12e7-5f75-a814-5d72ed015d01","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}