{"id":"b3d4159b-aa71-5194-9b4f-2b2df3bc2473","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-act-skin-photoconversion","predicate":"photoconverts_to","statement":"Narrow-band ultraviolet irradiation converted cutaneous 7-dehydrocholesterol to previtamin D3; 295-300 nm was the most effective tested range.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"dd9c2e63-1a8e-5b38-8c77-988ee5759a50","mechanism_event_label":"UVB starts the skin pathway that makes vitamin D3.","subject":{"id":"f8abe141-5f9e-5028-9b3e-e524e0b8afc4","slug":"7-dehydrocholesterol","display_name":"7-Dehydrocholesterol","entity_type_key":"small_molecule"},"object":{"id":"a1afa10a-5cad-5821-b11c-35a98b3fc4c5","slug":"previtamin-d3","display_name":"Previtamin D3","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"dd9c2e63-1a8e-5b38-8c77-988ee5759a50","stable_key":"1deb434a-3547-51a0-a038-87b1ce79ec38:vd-act-skin-photoconversion-event","event_type":"biochemical_relationship","label":"UVB starts the skin pathway that makes vitamin D3.","description":"Narrow-band ultraviolet irradiation converted cutaneous 7-dehydrocholesterol to previtamin D3; 295-300 nm was the most effective tested range.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"f8abe141-5f9e-5028-9b3e-e524e0b8afc4","slug":"7-dehydrocholesterol","display_name":"7-Dehydrocholesterol","entity_type_key":"small_molecule"},"role":"substrate","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"a1afa10a-5cad-5821-b11c-35a98b3fc4c5","slug":"previtamin-d3","display_name":"Previtamin D3","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Primary abstract: optimal 295-300 nm; up to 65% conversion under 295-nm radiation.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human skin irradiation with chemical product measurements","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Narrow-band radiation; up to 65% conversion at 295 nm; fluence/time not in retrieved abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Controlled photochemistry; no safe or universally effective sunlight duration follows.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient","value_text":"Vitamin D2 and D3","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"nutrient_topic","value_text":"Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-d","display_name":"Vitamin D2 and D3","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"UVB starts the skin pathway that makes vitamin D3.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[maclaughlin1982] Spectral character of sunlight modulates photosynthesis of previtamin D3 and its photoisomers in human skin. (1982). https://pubmed.ncbi.nlm.nih.gov/6281884/ DOI: 10.1126/science.6281884","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"skin","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"756db153-5e3f-58ce-8d0d-bb8eebd50f1c","evidence_kind":"source_excerpt","locator":"Lines 91-104","start_line":91,"end_line":104,"excerpt":"### vd-act-skin-photoconversion\nNarrow-band ultraviolet irradiation converted cutaneous 7-dehydrocholesterol to previtamin D3; 295-300 nm was the most effective tested range.\nCondition category: normal\nnutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: UVB starts the skin pathway that makes vitamin D3.\norganism: Homo sapiens\ntissue_or_cell_type: skin\nexperimental_model: Human skin irradiation with chemical product measurements\nlimitations: Controlled photochemistry; no safe or universally effective sunlight duration follows.\nexposure: Narrow-band radiation; up to 65% conversion at 295 nm; fluence/time not in retrieved abstract.\ncross_nutrient: false\nevidence_location: Primary abstract: optimal 295-300 nm; up to 65% conversion under 295-nm radiation.\nnutrient: Vitamin D2 and D3\n[maclaughlin1982] Spectral character of sunlight modulates photosynthesis of previtamin D3 and its photoisomers in human skin. 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