{"id":"6da1d615-4b77-541c-83b4-91887ad7ec28","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-redox-nadk2-knockdown-viability-null","predicate":"did_not_change_detectably","statement":"The same short NADK2-knockdown experiment did not detect reduced HEK293A viability, including in the tested menadione condition.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"neutral","is_public":true,"mechanism_event_id":"21a9b735-472f-52fb-9d71-4af93081ce2a","mechanism_event_label":"The oxidant readout rose without a detected loss of viability over this interval.","subject":{"id":"eac1269b-354c-52d4-b3e6-26e6cd111632","slug":"nadk2","display_name":"NADK2","entity_type_key":"protein"},"object":{"id":"69e377ac-cb14-558d-be47-1a3505aa7726","slug":"hek293a-cell-viability","display_name":"HEK293A cell viability","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"21a9b735-472f-52fb-9d71-4af93081ce2a","stable_key":"a9dd23c6-978a-5755-8bd8-f29bd1fe0cda:b3-redox-nadk2-knockdown-viability-null-event","event_type":"observed_intervention","label":"The oxidant readout rose without a detected loss of viability over this interval.","description":"The same short NADK2-knockdown experiment did not detect reduced HEK293A viability, including in the tested menadione condition.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"eac1269b-354c-52d4-b3e6-26e6cd111632","slug":"nadk2","display_name":"NADK2","entity_type_key":"protein"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"69e377ac-cb14-558d-be47-1a3505aa7726","slug":"hek293a-cell-viability","display_name":"HEK293A cell viability","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/niacin-redox-sources/nadk2-2012.fulltext.txt\", \"locator\": \"Results\", \"start_char\": 16830, \"end_char\": 18219, \"file_sha256\": \"65209c0b4ea7220bc95afdd182e40910f2445345172956e85552d5c6db649648\", \"text_sha256\": \"5de49f80d76c73b6a308096c07b330e8d3d53ee28c6a06f4b2a331e4798b45d7\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"siRNA; calcein-AM and supporting MTT assays","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Three-day knockdown; viability experiment used 12.5 μM menadione for 20 h","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Null short-term viability result does not exclude longer-term injury or other cell-type responses; ROS and viability challenges used different concentrations.","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":"The oxidant readout rose without a detected loss of viability over this interval.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[nadk2-2012] Identification and characterization of a human mitochondrial NAD kinase. (2012). https://pubmed.ncbi.nlm.nih.gov/23212377/ DOI: 10.1038/ncomms2262","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"HEK293A cells","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":"e63e922c-6a75-5d40-856b-4990b4d5e8d4","evidence_kind":"source_excerpt","locator":"Lines 951-962","start_line":951,"end_line":962,"excerpt":"### b3-redox-nadk2-knockdown-viability-null\nThe same short NADK2-knockdown experiment did not detect reduced HEK293A viability, including in the tested menadione condition.\nCondition category: machinery_impairment\nnutrient_topic: Niacin research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The oxidant readout rose without a detected loss of viability over this interval.\norganism: Homo sapiens\ntissue_or_cell_type: HEK293A cells\nexperimental_model: siRNA; calcein-AM and supporting MTT assays\nlimitations: Null short-term viability result does not exclude longer-term injury or other cell-type responses; ROS and viability challenges used different concentrations.\nexposure: Three-day knockdown; viability experiment used 12.5 μM menadione for 20 h\nevidence_span: {\"source_cache\": \"artifacts/niacin-redox-sources/nadk2-2012.fulltext.txt\", \"locator\": \"Results\", \"start_char\": 16830, \"end_char\": 18219, \"file_sha256\": \"65209c0b4ea7220bc95afdd182e40910f2445345172956e85552d5c6db649648\", \"text_sha256\": \"5de49f80d76c73b6a308096c07b330e8d3d53ee28c6a06f4b2a331e4798b45d7\"}\n[nadk2-2012] Identification and characterization of a human mitochondrial NAD kinase. 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