A303 SIMULTANEOUS PRESSURE WAVES ARE A KEY COMPONENT OF HUMAN COLON MOTOR FUNCTION ASSESSMENT, USING HIGH-RESOLUTION COLONIC MANOMETRY (HRCM)
Bibliographic record
Abstract
Colonic dysmotility is common, yet its nature is not fully understood through low-resolution manometry. High-Resolution Colonic Manometry (HRCM) is capable of revealing detailed motor patterns and their functions can be tested in the clinical setting. Our objective was to identify clinically relevant propulsive motor patterns in healthy volunteers and to improve interpretation of motor pattern functions through an in vitro study of equivalent patterns in the proximal rabbit colon. Healthy adult volunteers (n=13) received 84-sensor HRCM with different stimuli: balloon distention in proximal and transverse colon, a meal, and bisacodyl in the proximal colon and rectum. In rabbits (n=7) pressure patterns (by HRCM) and motor patterns (by video-recorded diameter changes expressed as spatio-temporal maps) were recorded simultaneously, in vitro, to characterize propulsive pressure patterns. In adult volunteers, High Amplitude Propagating Pressure Waves (HAPCs) were only observed after stimulation (balloon distention or bisacodyl administration). In contrast, Simultaneous Pressure Waves (SPWs) were observed at baseline. SPWs ranged in amplitude from 5 mmHg to >100 mmHg. SPWs were associated with gas and/or content expulsion and internal sphincter relaxation, consistent with a propulsive and neurogenic nature. Gas expulsion never occurred without SPWs. SPWs spanned between 80% and 100% of the colon. Proximal HAPCs sometimes developed into SPWs. SPWs increased in response to a meal and became prominent in amplitude during balloon distention and after bisacodyl administration. In response to bisacodyl, higher amplitude SPWs were associated with an urge to defecate. SPWs were found to occur in isolation or forming a rhythmic pattern with a dominant frequency of ~ 1 wave/min. When forming a rhythmic pattern, SPWs could inhibit non-propulsive motor patterns suggesting that the absence of a motor pattern can be due to competition from propulsive activity. Studies in the rabbit model identified SPWs similar to those found in humans, with SPWs caused by fast propagating contractions with velocities greater than 5 cm/s and associated with expulsion of colonic contents. The literature suggests that SPWs are artifacts or inhibit transit. Here we report that SPWs are the most common propulsive motor activity of the human colon, associated with internal anal sphincter relaxation and gas or content expulsion. SPWs should be considered, together with HAPCs, as an important propulsive motility pattern to characterize when evaluating motor patterns in patients with colonic dysmotility. CIHRHamilton Academic Health Sciences Organization (Ratcliffe)
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 | 0.001 |
| 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 | 0.000 | 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".