Ions released from metal-on-metal hip implants: «in vitro» and «in vivo» investigations
Bibliographic record
Abstract
Studies have shown that Co and Cr particles and ions can enter the bloodstream and accumulate in tissues and organs of patients after metal-on-metal (MM) total hip arthroplasty (THA). These ions can generate reactive oxygen species (ROS) that can be deleterious for cells. We first assessed the biological effects of Cr(VI), Co(II), and Cr(III) by testing their effect on antioxidant enzymes (SODs, CAT, GPx, HO-1) that represent a primary defense system against ROS. We demonstrated that Cr(VI) induced the protein expression (translation) of antioxidant enzymes, whereas it had no effect on the mRNA expression (transcription). Co(II) induced the expression of both protein and mRNA of HO-1 only. Cr(III) had no effect on the activity of these enzymes. We then suggested that a difference in molecular structure may be at the origin of their differential effects and showed that Cr(III) can form precipitable complexes, whereas Co(II) and Cr(VI) cannot form complexes in the same experimental conditions. These Cr(III) complexes, formed in simulated-physiological fluids, were constituted by an organic phase (amino acids, phosphate) tangled with an inorganic phase (Cr, Ca, Na). Interestingly, these Cr(III) complexes interacted only with albumin in presence of fetal bovine serum, whereas they interacted with 8 different human serum proteins in presence of human serum. The interaction of Cr(III) complexes with serum proteins affect their internalization by macrophages, complexes formed with human serum being more easily internalized than those bound to bovine proteins. Lastly, results suggested that the levels of Co and Cr ions in patients with MM THA are not sufficient to induce significant oxidative stress in the blood of these patients, bringing optimism over concern for the long term biological effects of Co and Cr ions released from metal-metal bearings. In conclusion, this thesis gives very valuable information on the biological effects of Cr and Co ions and gives insight i
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 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| 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 | 0.000 |
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 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".