Our understanding of human colonic motility, and autonomic reflexes that generate motor patterns, has increased markedly through high-resolution manometry. Details of the motor patterns are emerging ...related to frequency and propagation characteristics that allow linkage to interstitial cells of Cajal (ICC) networks. In studies on colonic motor dysfunction requiring surgery, ICC are almost always abnormal or significantly reduced. However, there are still gaps in our knowledge about the role of ICC in the control of colonic motility and there is little understanding of a mechanistic link between ICC abnormalities and colonic motor dysfunction. This review will outline the various ICC networks in the human colon and their proven and likely associations with the enteric and extrinsic autonomic nervous systems. Based on our extensive knowledge of the role of ICC in the control of gastrointestinal motility of animal models and the human stomach and small intestine, we propose how ICC networks are underlying the motor patterns of the human colon. The role of ICC will be reviewed in the autonomic neural reflexes that evoke essential motor patterns for transit and defecation. Mechanisms underlying ICC injury, maintenance, and repair will be discussed. Hypotheses are formulated as to how ICC dysfunction can lead to motor abnormalities in slow transit constipation, chronic idiopathic pseudo-obstruction, Hirschsprung's disease, fecal incontinence, diverticular disease, and inflammatory conditions. Recent studies on ICC repair after injury hold promise for future therapies.
Fermented foods play a significant role in the human diet for their natural, highly nutritious and healthy attributes. Our aim was to study the effect of yeast extract, a fermented substance ...extracted from natural yeast, on colonic motility to better understand its potential therapeutic role. A yeast extract was given to rats by gavage for 3 days, and myogenic and neurogenic components of colonic motility were studied using spatiotemporal maps made from video recordings of the whole colon ex vivo. A control group received saline gavages. The yeast extract caused excitation of the musculature by increasing the propagation length and duration of long‐distance contractions, the major propulsive activity of the rat colon. The yeast extract also evoked rhythmic propulsive motor complexes (RPMCs) which were antegrade in the proximal and mid‐colon and retrograde in the distal colon. RPMC activity was evoked by distention‐induced neural activity, but it was myogenic in nature since we showed it to be generated by bethanechol in the presence of tetrodotoxin. In conclusion, ingestion of yeast extract stimulates rat colon motility by exciting neurogenic and myogenic control mechanisms.
The cyclic motor patterns in the human colon Pervez, Maham; Ratcliffe, Elyanne; Parsons, Sean P. ...
Neurogastroenterology and motility,
20/May , Volume:
32, Issue:
5
Journal Article
Peer reviewed
Background
High‐resolution colonic manometry gives an unprecedented window into motor patterns of the human colon. Our objective was to characterize motor activities throughout the entire colon that ...possessed persistent rhythmicity and spanning at least 5 cm.
Methods
High‐resolution colonic manometry using an 84‐channel water‐perfused catheter was performed in 19 healthy volunteers. Rhythmic activity was assessed during baseline, proximal balloon distention, meal, and bisacodyl administration.
Key Results
Throughout the entire colon, a cyclic motor pattern occurred either in isolation or following a high‐amplitude propagating pressure wave (HAPW), consisting of clusters of pressure waves at a frequency centered on 11‐13 cycles/min, unrelated to breathing. The cluster duration was 1‐6 minutes; the pressure waves traveled for 8‐27 cm, lasting 5‐8 seconds. The clusters itself could be rhythmic at 0.5‐2 cpm. The propagation direction of the individual pressure waves was mixed with >50% occurring simultaneous. This high‐frequency cyclic motor pattern co‐existed with the well‐known low‐frequency cyclic motor pattern centered on 3‐4 cpm. In the rectum, the low‐frequency cyclic motor pattern dominated, propagating predominantly in retrograde direction. Proximal balloon distention, a meal and bisacodyl administration induced HAPWs followed by cyclic motor patterns.
Conclusions and Inferences
Within cyclic motor patterns, retrograde propagating, low‐frequency pressure waves dominate in the rectum, likely keeping the rectum empty; and mixed propagation, high‐frequency pressure waves dominate in the colon, likely promoting absorption and storage, hence contributing to continence. Propagation and frequency characteristics are likely determined by network properties of the interstitial cells of Cajal.
High‐resolution colonic manometry allows detailed assessment of human colon motor function and dysfunction. Here, a cyclic motor pattern at ~12 cycles/min follows a high‐amplitude propagating pressure wave at 160 mm Hg. It may restore the absorption and mixing condition after a mass movement of content.
(MR) is rich in anthocyanins, and it has good anti-cancer, anti-aging, antioxidant, and antiviral effects. The proportion of disability and death caused by ischemic stroke gradually increased, ...becoming a major disease that is harmful to human health. However, research on effects of anthocyanin from MR on cerebral ischemia-reperfusion (I/R) injury is rare. In this study, we prepared eight purified anthocyanin extracts (PAEs) from different types of MR, and examined the amounts of total anthocyanin (TA) and cyanidin-3-
-glucoside (C-3-G). After one week of PAE treatment, the cerebral infarction volume, disease damage, and contents of nitric oxide and malondialdehyde were reduced, while the level of superoxide dismutase was increased in I/R mice. Altogether, our results show that Boqi¹ MR contained the most TA (22.07%) and C-3-G (21.28%), and that PAE isolated from Dongkui MR can protect the brain from I/R injury in mice, with the mechanism possibly related to the Toll-like receptor 4 (TLR4)/ nuclear factor-κB (NF-κB) and NOD-like receptor pyrin domain-containing 3 protein (NLRP3) pathways.
With the advancement of technology and the widespread of coronavirus disease 2019 pandemic, catering operators have favored electronic ordering due to its convenience and safety. However, little ...research has examined whether the change from traditional waiter ordering to electronic device ordering would affect consumers' healthy eating. Based on previous research of self‐control, this article explores whether ordering by electronic device or waiter prompts healthier food choices. Through four experimental studies conducted in China, our findings demonstrated that whether ordering by electronic device or waiter is also one determinant of healthy eating. Compared to waiter ordering, consumers would make healthier food choices through electronic ordering, because it relives the time pressure brought on by the interpersonal waiter interaction. Whereas electronic ordering may be effective only if there is no waiting line or only for consumers who have a relatively low degree of trait self‐control. The findings advance the understanding of determinants of healthy eating, as well as enrich the literature that explores the difference between human and electronic service.
Background
Gastroenterologists have ignored or emphasized the importance of the rectosigmoid junction in continence or constipation on and off for 200 years. Here, we revisit its significance using ...high-resolution colonic manometry.
Methods
Manometry, using an 84-channel water-perfused catheter, was performed in 18 healthy volunteers.
Results
The rectosigmoid junction registers as an intermittent pressure band of 26.2 ± 7.2 mmHg, or intermittent phasic transient pressure increases at a dominant frequency of 3 cpm and an amplitude of 28.6 ± 8.6 mmHg; or a combination of tone and transient pressures, at a single sensor, 10–17 cm above the anal verge. Features are its relaxation or contraction in concert with relaxation or contraction of the anal sphincters when a motor pattern such as a high-amplitude propagating pressure wave or a simultaneous pressure wave comes down, indicating that such pressure increases or decreases at the rectosigmoid junction are part of neurally driven programs. We show that the junction is a site where motor patterns end, or where they start; e.g. retrogradely propagating cyclic motor patterns emerge from the junction.
Conclusions
The rectosigmoid junction is a functional sphincter that should be referred to as the sphincter of O’Beirne; it is part of the “braking mechanism,” contributing to continence by keeping content away from the rectum. In an accompanying case report, we show that its excessive presence in a patient with severe constipation can be a primary pathophysiology.
Background
Activating luminal 5‐HT4 receptors results in the release of 5‐HT from enterochromaffin cells into the lamina propria to modulate colonic motility. Our aim was to evaluate characteristics ...of colonic motor patterns involved in the prokinetic effects of intraluminal prucalopride in the rabbit colon.
Methods
Colonic motor patterns were studied ex vivo using simultaneous spatiotemporal diameter mapping and pressure sensing.
Key Results
Intraluminal prucalopride and intraluminal exogenous 5‐HT strongly evoked or enhanced the colonic motor complex at all levels of excitation beginning with generation of clusters of fast propagating contractions (FPCs), then development of long‐distance contractions (LDCs) within the clusters, and finally forceful LDCs as the highest level of excitation. Intraluminal prucalopride and intraluminal exogenous 5‐HT stimulated propulsive motor activity in a dose‐dependent and antagonist‐sensitive manner by increasing the contraction amplitude, intraluminal pressure, frequency, velocity, and degree of propagation of the colonic motor complex.
Conclusions and Inferences
Activating mucosal 5‐HT4 receptors via intraluminal prucalopride or 5‐HT increases propulsive motor activity in a graded manner; that is, depending on starting conditions, amplitudes or frequencies of an activity may increase or a new pattern may be initiated. Our data support further studies into delivering 5‐HT4 receptor agonists via colon‐targeted drug delivery systems and studies into the role of luminal 5‐HT as an essential requirement for normal colon motor pattern generation.
Activating luminal 5‐HT4 receptors can regulate colonic motility. Our aim was to evaluate motor patterns involved in the prokinetic effects of intraluminal prucalopride. Intraluminal prucalopride or intraluminal exogenous 5‐HT enhanced propulsive motor patterns in a graded, dose‐dependent, and 5‐HT4 receptor antagonist‐sensitive manner manifesting various levels of excitation. Luminal prucalopride may become a preferred prokinetic for slow transit constipation. Luminal serotonin may play a physiological role in colonic motility via 5‐HT4 receptors.
Aspergillus niger
and
Yarrowia lipolytica
are highly important in citric acid (CA) production. To further minimize the cost of CA bio-production using
A. niger
and
Y
.
lipolytica
, some strategies ...(e.g., metabolic engineering, efficient mutagenesis, and optimal fermentation strategies) were developed to enhance CA production and low-cost carbon sources were also utilized to decrease CA bio-production cost. In this review, we summarize the recent significant progresses in CA bio-production, including metabolic engineering, efficient mutagenesis and screening methods, optimal fermentation strategies, and use of low-cost carbon sources, and future prospects in this field are also discussed, which could help in the development of CA production industry.
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