Use of the thyrocyte sodium iodide symporter as the basis for a perchlorate cell-based assay
Bibliographic record
Abstract
Perchlorates are strong oxidants widely employed in military and civilian energetic materials and recently have been scrutinized as persistent environmental pollutants. The perchlorate anion, ClO(4)(-), is a well-known and potent competitive inhibitor of iodide transport by the sodium iodide symporter (NIS) expressed in the basolateral membranes of thyroid follicular cells (thyrocytes). Iodide uptake by thyroid follicular cells is rapid and reproducible. The competitive radiotransporter assay in this study shows promise as a rapid and convenient method to assay for ClO(4)(-) in water samples at the nM level. This work describes the initial efforts to define the assay conditions that enhance NIS selectivity for ClO(4)(-). Experiments of 10 min co-incubation of ClO(4)(-) and (125)I(-) demonstrate a more significant effect on (125)I(-) transport, with a quantifiable ClO(4)(-) concentration range of 50 nM (5 ppb) to 2 microM (200 ppb), and IC(50) of 180 nM (18 ppb), nearly three-fold lower than previous reports. Since the IC(50) in our assay for other known competitor anions (SCN(-), ClO(3)(-), NO(3)(-)) remains unchanged from previous research, the increased sensitivity for ClO(4)(-) also produces a three-fold enhancement in selectivity. In addition to the possible applicability of the thyrocyte to the development of a cellular perchlorate biosensor, we propose that the high affinity of the NIS for ClO(4)(-) also creates the potential for exploiting this membrane protein as a selective, sensitive, and broadly applicable biomechanical mechanism for controlled movement and concentration of perchlorate.
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.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.002 |
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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".