Effect of cigarette smoke on fibroblast-mediated gel contraction is dependent on cell density
Bibliographic record
Abstract
Cigarette smoke exposure has been associated with a variety of diseases, including emphysema. The current study evaluated the interaction of cell density and cigarette smoke extract (CSE) on fibroblast contraction of collagen gels. Protein levels of transforming growth factor (TGF)-beta1, fibronectin, PGE(2), and TGF-beta1 mRNA were quantified. Although both 5 and 10% CSE inhibited contraction by low-density fibroblasts (1 x 10(5) cell/ml), only 5% CSE augmented contraction in higher-density cultures (3-5 x 10(5) cells/ml). CSE also inhibited fibronectin and TGF-beta1 production in low-density cultures but stimulated fibronectin production in high-density cultures. Active TGF-beta1 was readily detectable only in higher-density cultures and was markedly augmented by 5% CSE. In contrast, although TGF-beta1 mRNA expression was inhibited in high-density cultures by 10% CSE, expression was increased in the presence of 5% CSE. These results suggest that CSE-induced inhibition of low-density fibroblast contraction is due to inhibition of fibronectin production, whereas CSE's stimulatory effect on high-density cells is the result of increased release of TGF-beta1. These effects may help explain the varied pathologies associated with exposure to cigarette smoke.
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 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) | 0.001 | 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 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".