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topical membership is not evidence of a direct dietary effect.\nplain_language: A second splice form retained transport activity.\norganism: Human constructs; human and canine host cells\ntissue_or_cell_type: ARPE19; MDCK; human colon\nexperimental_model: Human SLC44A4 isoforms expressed in ARPE19 cells; polarized MDCK imaging.\nlimitations: Not evidence for untested isoform 2.\nevidence_locator: Figure 10\nevidence_spans: [{\"source_document\": \"artifacts/thiamine_transport_sources/PMC3924303.txt\", \"start_char\": 39610, \"end_char\": 40292}]\nevidence-scope: ARPE19; MDCK; human colon\n[nabokina-2014-slc44a4] Molecular identification and functional characterization of the human colonic thiamine pyrophosphate transporter (2014). https://pmc.ncbi.nlm.nih.gov/articles/PMC3924303/ DOI: 10.1074/jbc.M113.528257","model_system":"Human SLC44A4 isoforms expressed in ARPE19 cells; polarized MDCK imaging.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [nabokina-2014-slc44a4] Molecular identification and functional characterization of the human colonic thiamine pyrophosphate transporter (2014). https://pmc.ncbi.nlm.nih.gov/articles/PMC3924303/ DOI: 10.1074/jbc.M113.528257","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}