<title>Photofrin mediated PDT in normal rat brain: assessment on apoptosis as a quantitative biological endpoint</title>
Bibliographic record
Abstract
The extent of the apoptotic response of normal rat brain tissue to Photofrin-mediated photodynamic therapy was determined following sub-necrotic light exposures. Wistar rats were injected with 12.5 mg kg<SUP>-1</SUP> Photofrin and the brain surface was exposed to 1-17 J cm<SUP>-2</SUP> of 630 nm light 24 hours later. In order to identify apoptotic cells on tissue sections 24 hour post treatment, the TUNEL assay was used to fluorescently label DNA cleavage, with propidium iodide as a control counter stain. Confocal laser scanning microscopy was used to quantify the local spatial density of apoptotic bodies and to determine their depth distribution in the tissue from the irradiated surface. Radiant exposures of 1-3 J cm<SUP>-2</SUP> produced the highest apoptotic response, which occurred in well-circumscribed volumes, without evidence of gross tissue necrosis. Up to 40 percent of all cells in the treatment field were positively stained, with more apoptotic bodies observed at the edge of the lesion. The number of TUNEL-positive cells was lower at 5 and 17 J cm<SUP>-2</SUP>. The apoptotic depth distribution was correlated with the light fluence distribution in the tissue over a limited depth range. Beyond this range there is evidence of a threshold for apoptosis, while at small depth and height radiant exposures there is a significant reduction in observed apoptosis. Hence, there is evidence that apoptosis is 'inhibited' by the presence of PDT-induced necrosis.
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 | 0.001 |
| 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 | 0.000 |
| 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 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".