A288 ANAL SPHINCTER RELAXATION ASSOCIATED WITH THE DEFECATION REFLEX AND GAS EXPULSION, ASSESSED BY HIGH-RESOLUTION COLONIC MANOMETRY
Notice bibliographique
Résumé
Continence and defecation require coordination between colonic motor patterns and internal anal sphincter relaxation, yet these relationships are not well understood. Our aim was to investigate the coordination between human colonic motor patterns and anal sphincter activity. High-Resolution Colonic Manometry (HRCM) was performed using an 84 sensor water-perfused catheter (1 cm spacing) in 14 healthy subjects. Colonic motor patterns and anorectal activity were recorded at baseline and provoking conditions (after a meal, balloon distensions, and luminal bisacodyl administration). A highly rhythmic alternation of contraction and relaxation of the internal AS in resting condition was observed in all subjects: a low-frequency rhythmicity at 1.2 ± 0.3 cpm with slowly developing and declining contraction, and a high-frequency rhythmicity at 15.0 ± 2.7 cpm superimposed on the slow rhythmicity. The High Amplitude Pressure Wave (HAPW) (Chen et al., 2017) was not routinely associated with IAS relaxation. However, 62.5% of HAPWs were associated with a brief transient relaxation at the onset of the HAPW in the proximal colon, which did not last for the duration of the HAPW. Gas expulsion was associated with Simultaneous Pressure Waves (SPWs), pan-colonic pressurizations that penetrated into the anal canal and were most often associated with strong relaxation of the IAS. Many HAPWs terminated in the mid or descending colon but were immediately followed by an SPW and this was accompanied by IAS relaxation. A total of 61 independent SPWs with a mean amplitude of 26.3 ± 7.9 mmHg, were associated with 50.2 ± 12.7% % IAS relaxation from 65.1 ± 15.6 mmHg to 31.5 ± 11.3 mmHg. Bisacodyl induced SPWs of highest amplitude (30.3 ± 4.7 mmHg), that were followed by 63.8 ± 9.0% IAS relaxation, compared to SPWs occurring at baseline of 23.8 ± 5.6 mmHg associated with 44.3 ± 12.4% IAS relaxation. Duration of relaxation was correlated neither with the amplitude of SPW nor the percentage of IAS relaxation. Out of 44 HAPWs analyzed, 27.2% were not associated with IAS relaxation, whereas 72.8% were accompanied by a transient IAS relaxation of 51.2 ± 17.3% at the onset of the HAPW which recovered during the progression of the HAPW. 45.4% of HAPWs (103.3 ± 24.0 mmHg) were immediately followed by SPWs (18.7 ± 6.5 mmHg), which were then associated with strong IAS relaxation of 66.9 ± 13.6%, going from 63.2 ± 19.4 mmHg to 20 ± 8.6 mmHg. The SPW, either in isolation and associated with gas expulsion or following an HAPW as part of the defection reflex, is consistently associated with internal anal sphincter relaxation. This relaxation reduces IAS tone which is maintained by rhythmic contractile activity. Chen JH, et al. (2017). Nature’s Scientific Reports doi:10.1038/srep41436. High-Resolution Colonic Manometry (HRCM) with 84 sensors, 1 cm apart. A simultaneous pressure wave (SPW), following a High Amplitude Pressure Wave (HAPW), penetrates into the anal canal and is associated with internal anal sphincter (IAS) relaxation. CIHRHamilton Academic Health Sciences Organization and the Canadian Foundation for Innovation
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Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».