Influence of Pregnancy on Plasma Cytokines and the Febrile Response to Intraperitoneal Administration of Bacterial Endotoxin in Rats
Bibliographic record
Abstract
Rats have an attenuated febrile response to exogenous (e.g. bacterial endotoxin) and endogenous pyrogen (e.g. interleukin-1beta) near the term of pregnancy, the mechanism of which is unknown. The present experiments were carried out on 71 non-pregnant and 181 pregnant Sprague-Dawley rats to determine if basal levels of the endogenous antipyretic substance, interleukin-1 receptor antagonist (IL-1ra), change relative to interleukin-1beta (IL-1beta) throughout gestation. Furthermore, we have constructed complete Escherichia coli lipopolysaccharide (LPS) dose-core temperature response curves in non-pregnant and pregnant rats on days 10, 15 and 20 of gestation (term of gestation approximately 21 days) to determine if the attenuated febrile response near the term of pregnancy results from a simple shift of the dose-response relationship or results from a dampening of the overall dose-response relationship. Basal IL-1beta, as determined by ELISA on trunk blood from non-pregnant and pregnant rats on days 10, 15 and 20 of gestation (d10, d15, d20), did not change significantly during pregnancy. Basal IL-1ra, however, was increased significantly in d15 rats as compared to non-pregnant, and d10 and d20 rats. The attenuated febrile response near the term of pregnancy, as determined by biotelemetry, did not result from a simple shift of the E. coli LPS dose-core temperature response curve but rather a dampening of the overall dose-response relationship. The febrile responses to EC(50) and EC(100) doses of E. coli LPS were preceded by a period of hypothermia, and were delayed and attenuated near the term of pregnancy as compared to that observed early in pregnancy and in non-pregnant rats. Our data provide evidence that pregnant rats are more sensitive to the hypothermia-producing effects of E. coli LPS than are non-pregnant rats and allow us to speculate that elevated basal IL-1ra may play a role in mediating the attenuated febrile response to pyrogen on day 15 but not on day 20 of gestation in rats.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| 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".