Characterization of uptake of folates by rat and human blood–brain barrier endothelial cells
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
This study aimed to characterize (3)H-folic acid ((3)H-FA) and (14)C-methyltetrahydrofolic acid ((14)C-MTHF) uptake by rat (RBE4) and human (hCMEC/D3) blood-brain barrier (BBB) endothelial cell lines. Uptake of (3)H-FA and (14)C-MTHF by RBE4 cells was time dependent and linear for the first 2 min of incubation; uptake by hCMEC/D3 cells showed a less marked time-dependency and a greater experimental variability. So, further experiments were performed in RBE4 cells only. Uptake of (3)H-FA was stimulated at acidic and alkaline pH, Na(+) dependent, stimulated when F(-) substituted for Cl(-), energy independent, inhibited by premetrexed, stimulated by cytochalasin D, and unaffected by MTHF, DIDS, SITS, methotrexate, monensin, and FA. Uptake of (14)C-MTHF was found to be pH-, Na(+)-, Cl(-)- and energy independent, inhibited by premetrexed and methotrexate, stimulated by cytochalasin D, and unaffected by FA, DIDS, SITS, monensin, and MTHF. RT-PCR analysis showed mRNA expression of reduced folate transporter (RFC), but neither of FRalpha nor of proton-coupled folate transporter (PCFT) in RBE4 cells, and mRNA expression of RFC and PCFT, but not of FRalpha, in hCMEC/D3 cells. In conclusion, both human and rat BBB endothelial cells show little capacity for (3)H-FA and (14)C-MTHF apical uptake. Hence, these cell lines do not appear to be a good model to study the transport of folates at the BBB.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it