Persistence of Vascular Calcification: A Failure of Cell-Mediated Resorption
Bibliographic record
Abstract
BACKGROUND: Medial arterial calcification is a common lesion associated with aging, chronic kidney disease, and diabetes that can lead to poor outcomes. Because the calcification is extensive when first apparent clinically or even radiologically, optimal therapy should target reversal in addition to prevention. However, studies to date suggest that medial calcification is irreversible under physiological conditions. This lack of reversal was investigated further by implanting calcified human arteries or hydroxyapatite subcutaneously into mice, or culturing them with murine osteoclasts in vitro. METHODS: Calcified human tibial arteries, obtained from amputations and previously frozen, were implanted subcutaneously in the dorsum of mice. Mineral content was measured by microcomputed tomography before and after implantation and compared with the calcium content of implanted pure hydroxyapatite or murine bone particles, along with histology. Calcified arteries were also incubated in vitro with osteoclasts generated by treating murine macrophages with receptor activator of NF-κB (nuclear factor kappa B). RESULTS: There was no decrease in mineral content of implanted arteries over 6 weeks and only minimal loss of calcium in devitalized bone particles, compared with almost complete resorption of hydroxyapatite. No resorption of hydroxyapatite occurred when implanted within a cell-impermeable diffusion chamber. Multinucleated giant cells, negative for osteoclast markers, were numerous among implanted hydroxyapatite, but rare in implanted arteries and bone. There was no histological evidence of resorption in calcified arteries incubated with osteoclasts. CONCLUSIONS: Hydroxyapatite is readily reabsorbed in vivo by a cell-mediated process not involving osteoclasts. The lack of resorption of medial arterial calcifications, even in the presence of osteoclasts, indicates that calcifications have properties that prevent cell-mediated resorption. Further studies are needed to identify these properties and develop strategies to overcome this.
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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".