Response to mannitol in asymptomatic subjects with airway hyper‐responsiveness to methacholine
Bibliographic record
Abstract
BACKGROUND: Bronchial provocation using methacholine, a cholinergic agonist, causes airway narrowing directly by contraction of bronchial smooth muscle. While methacholine has a high sensitivity for identifying airway hyper-responsiveness (AHR), it does not have a high specificity to diagnose asthma and false-positive responses may be observed in non-asthmatics. Mannitol is an osmotic stimulus that acts indirectly to cause airway narrowing by release of endogenous bronchoconstricting mediators. OBJECTIVES: We tested the hypothesis that subjects with asymptomatic AHR to methacholine would not have AHR to mannitol. METHODS: Sixteen subjects with a methacholine PD(20) <8 micro mol were challenged with mannitol. A positive response to mannitol was defined as a 15% decline in forced expiratory volume in 1 s (FEV(1)) after <635 mg (PD(15)). Expired nitric oxide (eNO) and blood eosinophils were also measured. RESULTS: The GM PD(20) for methacholine was 2.25 micro mol [95% confidence interval (CI): 2.19-5.29], the mean eNO was 14.7 p.p.b. (CI: 10.1-19.4) and the eosinophil count was 0.20 x 10(-9)/L (CI: 0.14-0.27 x 10(-9)/L). Only one subject (a smoker, 10 pack-years, FEV(1) 76% pred, non-allergic rhinitis, normal eNO and eosinophil count) also had a mild positive response to mannitol (PD(15): 451 mg). CONCLUSIONS: The response to mannitol was within the normal range in asymptomatic subjects with AHR to methacholine. Further evidence on the responsiveness to mannitol compared with methacholine in a random population sample is required to elucidate whether mannitol is a more specific test for diagnosing asthma.
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) | 0.000 | 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 | 0.001 | 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".