Orbicularis oculi muscle biopsies for mitochondrial DNA analysis in suspected mitochondrial myopathy
Bibliographic record
Abstract
AIMS: We wished to demonstrate the feasibility of performing diagnostic mitochondrial DNA (mtDNA) analysis on biopsies of the orbicularis oculi muscle in patients with a chronic progressive external ophthalmoplegia (CPEO) phenotype and suspicion of an underlying mitochondrial disorder. METHOD: Case series of three patients who underwent ptosis surgery and had simultaneous biopsy of the orbicularis oculi muscle because of a suspicion of a mitochondrial disorder. Orbicularis muscle samples were divided into two pieces at the time of biopsy. The first was snap-frozen in liquid nitrogen, DNA was extracted and mtDNA deletion analysis was performed by two complementary methods (long PCR and Southern blot analysis). The second piece of muscle was assessed using routine histopathology, electron microscopy and immuno-histochemical analysis. RESULTS: Three patients with clinical features of CPEO, without any positive family history, underwent orbicularis muscle biopsies at time of eyelid ptosis surgery. All biopsies were adequate to conduct histopathological and immuno-histochemical analysis, which showed evidence of abnormal muscle structure and function. mtDNA was successfully extracted from all biopsies, and long PCR and Southern blot analysis confirmed diagnostic large single mtDNA deletions in all three cases. CONCLUSIONS: Orbicularis oculi muscle biopsies are useful in patients with CPEO to perform mtDNA analysis, thus avoiding a separate biopsy of skeletal muscle elsewhere.
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 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".