{"id":"db5751cc-38a4-51ed-bda5-757e8eee8b80","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:thiamine-def-frozen-erythrocyte-stability","predicate":"more-stable-in-frozen-samples-than","statement":"Direct erythrocyte ThDP was more stable during frozen storage than transketolase activity in the evaluated preparations.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"532d9209-fadf-52cb-a6df-fab4008fc72c","mechanism_event_label":"Storage can affect the chemical measurement and the functional enzyme test differently.","subject":{"id":"fff22d5c-def5-56a2-9dde-f9667bece0a5","slug":"erythrocyte-thdp-concentration","display_name":"Erythrocyte thiamine diphosphate concentration","entity_type_key":"cellular_process"},"object":{"id":"af53ced7-4786-5ca1-8ada-701af6aa6aca","slug":"blood-transketolase-activity","display_name":"Blood transketolase activity","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"532d9209-fadf-52cb-a6df-fab4008fc72c","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:thiamine-def-frozen-erythrocyte-stability-event","event_type":"observed_intervention","label":"Storage can affect the chemical measurement and the functional enzyme test differently.","description":"Direct erythrocyte ThDP was more stable during frozen storage than transketolase activity in the evaluated preparations.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"187db168-8028-5ce6-9f8b-4bc61ebad1a0","slug":"thiamine-diphosphate","display_name":"Thiamine diphosphate","entity_type_key":"small_molecule"},"role":"direct analyte","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"c95c645c-ae67-5911-871e-4f796a17faec","slug":"tkt","display_name":"Human transketolase","entity_type_key":"protein"},"role":"enzyme activity analyte","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"fff22d5c-def5-56a2-9dde-f9667bece0a5","slug":"erythrocyte-thdp-concentration","display_name":"Erythrocyte thiamine diphosphate concentration","entity_type_key":"cellular_process"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"af53ced7-4786-5ca1-8ada-701af6aa6aca","slug":"blood-transketolase-activity","display_name":"Blood transketolase activity","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"evidence_location","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"ETDP is more stable than ETKA in frozen erythrocytes","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Human erythrocytes incubated with thiamine, plus alcoholic, elderly and student comparison groups; HPLC ThDP versus basal and ThDP-stimulated transketolase assays.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Laboratory assessment of thiamine status using erythrocytes or whole blood","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Historical assay comparison, not a validated stability duration for every modern collection tube or analytical platform.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Storage can affect the chemical measurement and the functional enzyme test differently.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[baines-1988-erythrocyte-assays] The Evaluation of Erythrocyte Thiamin Diphosphate as an Indicator of Thiamin Status in Man, and its Comparison with Erythrocyte Transketolase Activity Measurements (1988). https://journals.sagepub.com/doi/10.1177/000456328802500617 DOI: 10.1177/000456328802500617","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Frozen erythrocyte specimens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"biomarker_context","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"aaedf9dc-6176-55be-843a-1655eaf24a22","evidence_kind":"source_excerpt","locator":"Lines 1395-1407","start_line":1395,"end_line":1407,"excerpt":"### thiamine-def-frozen-erythrocyte-stability\nDirect erythrocyte ThDP was more stable during frozen storage than transketolase activity in the evaluated preparations.\nCondition category: biomarker_context\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Storage can affect the chemical measurement and the functional enzyme test differently.\norganism: Homo sapiens\ntissue_or_cell_type: Frozen erythrocyte specimens\nexperimental_model: Human erythrocytes incubated with thiamine, plus alcoholic, elderly and student comparison groups; HPLC ThDP versus basal and ThDP-stimulated transketolase assays.\nlimitations: Historical assay comparison, not a validated stability duration for every modern collection tube or analytical platform.\nevidence_location: Abstract\nevidence_span: ETDP is more stable than ETKA in frozen erythrocytes\nexposure: Laboratory assessment of thiamine status using erythrocytes or whole blood\n[baines-1988-erythrocyte-assays] The Evaluation of Erythrocyte Thiamin Diphosphate as an Indicator of Thiamin Status in Man, and its Comparison with Erythrocyte Transketolase Activity Measurements (1988). https://journals.sagepub.com/doi/10.1177/000456328802500617 DOI: 10.1177/000456328802500617","model_system":"Human erythrocytes incubated with thiamine, plus alcoholic, elderly and student comparison groups; HPLC ThDP versus basal and ThDP-stimulated transketolase assays.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [baines-1988-erythrocyte-assays] The Evaluation of Erythrocyte Thiamin Diphosphate as an Indicator of Thiamin Status in Man, and its Comparison with Erythrocyte Transketolase Activity Measurements (1988). https://journals.sagepub.com/doi/10.1177/000456328802500617 DOI: 10.1177/000456328802500617","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: 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":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}