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unverified.","entity":null},{"dimension":"evidence_location","value_text":"Abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"before and after activation with exogenous thiamin diphosphate","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":"Assay response is influenced by the enzyme preparation and assay conditions; a small response is not a measurement of every tissue.","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":"This asks how much extra cofactor can activate the sampled enzyme, whereas HPLC counts the cofactor itself.","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":"Erythrocyte hemolysates","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":"3aacfdd4-d198-57cc-b5c8-f44d93d0f7f0","evidence_kind":"source_excerpt","locator":"Lines 1381-1393","start_line":1381,"end_line":1393,"excerpt":"### thiamine-def-exogenous-thdp-functional-assay\nThe functional erythrocyte test compared transketolase activity before and after adding exogenous thiamine diphosphate.\nCondition category: biomarker_context\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: This asks how much extra cofactor can activate the sampled enzyme, whereas HPLC counts the cofactor itself.\norganism: Homo sapiens\ntissue_or_cell_type: Erythrocyte hemolysates\nexperimental_model: Human erythrocytes incubated with thiamine, plus alcoholic, elderly and student comparison groups; HPLC ThDP versus basal and ThDP-stimulated transketolase assays.\nlimitations: Assay response is influenced by the enzyme preparation and assay conditions; a small response is not a measurement of every tissue.\nevidence_location: Abstract\nevidence_span: before and after activation with exogenous thiamin diphosphate\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. 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