Mucosal changes in a long-term bovine intestinal segment model following removal of ingesta and microflora
Bibliographic record
Abstract
The intestinal immune system influences responses to both enteric pathogens and commensal microflora but few models are available to analyze mucosal immune responses to either enteric pathogens or commensal microflora. We surgically isolated ileal segments in 2-3 week old calves, infused antibiotics, and subdivided each segment into three compartments. Following a 6-8 week period the isolated ileal segments appeared grossly normal in 4 of 5 calves, retained compartmentalization, and contents were culture positive for either Enterococcus spp. or Escherichia coli. In a second experiment, isolated ileal segments were examined following a 9-11 month period and appeared grossly normal with compartmentalization retained in 8 of 11 animals. Streptococcus spp or Escherichia coli were cultured from segment contents collected from 3 of these 8 animals. Histology revealed a marked reduction in villus height in isolated ileal segments despite sustained crypt epithelium proliferation. Lymphoid follicles in ileal Peyer's patches were reduced in size but remained sites of active lymphoproliferation within segments. Significant mucosal T cell, macrophage, and dendritic cell depletion was observed in isolated ileal segments and T cell and NK cell depletion increased significantly in the absence of culturable bacteria. Finally, Toll-like receptor (TLR)-4 expression was decreased but TLR-5 and -6 expression increased in ileal segments. Thus, isolated ileal segments remained relatively stable for prolonged periods and significant changes in mucosal leukocyte populations were correlated with the presence or absence of culturable microflora. Stable, as opposed to sterile, isolated ileal segments provide an opportunity to analyze bovine mucosal immune responses in the presence or absence of commensal microflora.
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 | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 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".