The role of gama aminobutyric acid (GABA) in acute ischemic stroke
Bibliographic record
Abstract
P171 Background: GABA neurotransmission causes membrane hyperpolarization which may counterbalance the toxic effects of glutamate during cerebral ischemia. Although the neuroprotective action of a GABA agonist (Clomethiazole) on acute ischemic stroke is currently being investigated, the importance of GABA in human stroke is unknown. Objective: to analyze whether the concentrations of GABA were related to early stroke outcome in 258 patients with an acute hemispheric cerebral infarction. Methods: GABA was measured using HPLC in blood and CSF samples obtained within 24h from stroke onset, and in blood 48h after admission. Stroke was classified according to Bamford’s scheme. Deterioration was diagnosed if Canadian stroke scale dropped 1 or more points during the first 48h after inclusion. The relative importance of GABA for neurologic worsening was evaluated by logistic regression analysis. Results: GABA concentrations (nmol/L) in plasma and CSF were significantly lower in TACS (108±86 and 44±20) than in PACS (240±164 and 87±60), LACS (377±136 and 134±43), and POCS (374±137 and 134±35) (all p<0.0001). There was a significant linear correlation between plasma and CSF values of GABA (r=0.70, p<0.001). Neurologic deterioration occurred in 87 patients (33.7%). In TACS and PACS, mean plasma and CSF levels of GABA at admission were three fold lower in patients with progressing stroke than in those without worsening (all p<0.0001); in LACS and POCS they were 40% lower in patients with progression (p<0.01). GABA concentrations of less than 190 nmol/L in plasma (OR,13.0; 95%CI, 3.8 to 44.8), and of less than 82 nmol/L in CSF (OR,20.3; 95%CI, 5.6 to 71.8) were significantly associated with neurologic worsening after adjusting for age, inclusion delay, serum glucose, body temperature, and stroke severity on admission, and ultimate infarct volume. Mean plasma GABA levels did not change at 48h in patients with deterioration, but increased a 17% in those who improved or remained stable (Wilcoxon, p<0.001). Conclusions: Early neurologic deterioration in acute ischemic stroke is related to low GABA concentrations in blood and CSF, particularly in patients with total or partial anterior circulation syndromes.
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 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 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 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".