Decreased Mineral Content in MMP-20 Null Mouse Enamel is Prominent During the Maturation Stage
Bibliographic record
Abstract
During enamel development, matrix metalloproteinase-20 (MMP-20, enamelysin) is expressed early during the secretory stage as the enamel thickens, and kallikrein-4 (KLK-4, EMSP1) is expressed later during the maturation stage as the enamel hardens. Thus, we investigated whether the physical properties of the secretory-/maturation-stage MMP-20 null enamel were significantly different from those of controls. We demonstrated that although, in relative terms, the weight percent of mature mineral in the MMP-20 null mouse enamel was only 7-16% less than that in controls, overall the enamel mineral was reduced by about 50%, and its hardness was decreased by 37%. Percent mineral content by weight was assessed at 3 different developmental stages. Remarkably, the biggest difference in mineral content between MMP-20 null and controls occurred in the nearly mature enamel, when MMP-20 is normally no longer expressed. This suggests that MMP-20 acts either directly or indirectly to facilitate the removal of maturation-stage enamel proteins.
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How this classification was reachedexpand
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 | 0.001 | 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 | 0.001 |
| 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, 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".