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unverified.","entity":null},{"dimension":"evidence_location","value_text":"Results: BBB Dysfunction; Figure 5","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_span","value_text":"before the onset of apparent cell loss","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Dietary thiamine removal plus daily pyrithiamine in mice or rats","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"IgG localization is a permeability proxy; timing does not prove the barrier change caused later neuron death.","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":"Mus musculus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A blood protein crossed the barrier before overt tissue loss was visible.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Vulnerable thalamic and related regions","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":"7ba74144-cf33-54ae-95e2-ba61d5789d49","evidence_kind":"source_excerpt","locator":"Lines 1183-1195","start_line":1183,"end_line":1195,"excerpt":"### thiamine-def-bbb-igg-leak\nFocal extravascular IgG staining appeared in susceptible mouse brain regions by day 10, before obvious cell loss or hemorrhage.\nCondition category: nutrient_deficiency\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A blood protein crossed the barrier before overt tissue loss was visible.\norganism: Mus musculus\ntissue_or_cell_type: Vulnerable thalamic and related regions\nexperimental_model: Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.\nlimitations: IgG localization is a permeability proxy; timing does not prove the barrier change caused later neuron death.\nevidence_location: Results: BBB Dysfunction; Figure 5\nevidence_span: before the onset of apparent cell loss\nexposure: Dietary thiamine removal plus daily pyrithiamine in mice or rats\n[calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","model_system":"Adult male C57BL/6 mice and Fischer 344 Brown Norway F1 rats; thiamine-deficient diet plus pyrithiamine 0.5 mg/kg/day intraperitoneally; staged brain histochemistry.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [calingasan-1998-bbb-iron-nos] Induction of nitric oxide synthase and microglial responses precede selective cell death induced by chronic impairment of oxidative metabolism (1998). https://pmc.ncbi.nlm.nih.gov/articles/PMC1852979/ DOI: 10.1016/S0002-9440(10)65602-7","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}