Characterizing the evolution of lesion, penumbra and blood-brain barrier permeability in a photothrombotic juvenile rat stroke model using MRI and histology
Bibliographic record
Abstract
Pediatric stroke is a significant cause of childhood mortality and morbidity. The clinical research in this field bears certain limitations that do not exist in the pre-clinical setting. Experimental models of ischemic stroke show differences in lesion evolution and blood-brain barrier (BBB) permeability between adult and neonatal rats. However, little is known about these factors in the juvenile stage. Here, we characterize the evolution of the lesion, penumbra and degree of BBB permeability in a photothrombotic ring model of juvenile stroke using a mixed longitudinal and cross-sectional study. Fourteen Sprague Dawley juvenile rats (weight 130-189 g), lesion, penumbra volume and blood-brain barrier (BBB) leakage were measured longitudinally on days 0, 2, and 7 following photothrombotic stroke. Magnetic resonance imaging (MRI) techniques were used to measure lesion and penumbra volumes (T2-weighted imaging [T2]), water restriction (diffusion-weighted imaging [DWI]) and BBB leakage (with dynamic contrast-enhanced imaging [DCE]). To confirm stroke, histology was performed (n = 9) with Triphenyltetrazolium chloride staining (TTC) (n=9), (Haemotoxylin and Eosin (H&E) staining (n=3); andn Evans Blue (EB) staining to assess BBB permeability (n=9). We found the volume of the penumbra to be larger and better delineated on MRI and histology in the acute compared to the subacute and chronic stages. The lesion was smaller in volume and increased over time following same time trajectory. The BBB was most compromised at the hyperacute stage (day 0) and decreasingly, yet persistently, disrupted to day 7. Our in vivo and ex vivo findings provide insight into the evolution of stroke and could serve as a study model to test blood-brain barrier stabilization agents in the pediatric setting.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 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 | 0.001 |
| 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".