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1.
J Cell Mol Med ; 28(10): e18343, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760903

RESUMEN

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.


Asunto(s)
Colon , Motilidad Gastrointestinal , Animales , Colon/efectos de los fármacos , Colon/fisiología , Motilidad Gastrointestinal/efectos de los fármacos , Ratas , Masculino , Levaduras , Ratas Sprague-Dawley , Tetrodotoxina/farmacología
2.
Am J Physiol Gastrointest Liver Physiol ; 324(1): G1-G9, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36283962

RESUMEN

The machinery maintaining fecal continence prevents involuntary loss of stool and is based on the synchronized interplay of multiple voluntary and involuntary mechanisms, dependent on cooperation between motor responses of the musculature of the colon, pelvic floor, and anorectum, and sensory and motor neural pathways. Knowledge of the physiology of fecal continence is key toward understanding the pathophysiology of fecal incontinence. The idea that involuntary contraction of the internal anal sphincter is the primary mechanism of continence and that the external anal sphincter supports continence only by voluntary contraction is outdated. Other mechanisms have come to the forefront, and they have significantly changed viewpoints on the mechanisms of continence and incontinence. For instance, involuntary contractions of the external anal sphincter, the puborectal muscle, and the sphincter of O'Beirne have been proven to play a role in fecal continence. Also, retrograde propagating cyclic motor patterns in the sigmoid and rectum promote retrograde transit to prevent the continuous flow of content into the anal canal. With this review, we aim to give an overview of primary and secondary mechanisms controlling fecal continence and evaluate the strength of evidence.


Asunto(s)
Defecación , Incontinencia Fecal , Humanos , Defecación/fisiología , Recto/fisiología , Canal Anal/fisiología , Colon Sigmoide
3.
Am J Physiol Gastrointest Liver Physiol ; 325(4): G295-G305, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37461842

RESUMEN

Effective and widely available strategies are needed to diagnose colonic motility dysfunction. We investigated whether ultrasonography could generate spatiotemporal maps combined with motor pattern frequency analysis, to become a noninvasive method to characterize human colon motor patterns. Abdominal colonic ultrasonography was performed on healthy subjects (N = 7), focusing on the detailed recording of spontaneous haustral activities. We developed image segmentation and frequency analysis software to analyze the motor patterns captured. Ultrasonography recordings of the ascending, transverse, and descending colon identified three distinct rhythmic motor patterns: the 1 cycle/min and the 3 cycles/min cyclic motor pattern were seen throughout the whole colon, whereas the 12 cycles/min cyclic motor pattern was identified in the ascending colon. The rhythmic motor patterns of the human colon that are associated with interstitial cells of Cajal-associated pacemaking activity can be accurately identified and quantified using ultrasound.NEW & NOTEWORTHY Ultrasonography in the clinical field is an underutilized tool for assessing colonic motility; however, with the addition of frequency analysis techniques, it provides a method to identify human colonic motor patterns. Here we report on the 1, 3, and 12 cpm rhythmic motor patterns. Ultrasound has the potential to become a bedside assessment for colonic dysmotility and may reveal the health of interstitial cells of Cajal (ICC) pacemaker activities.


Asunto(s)
Motilidad Gastrointestinal , Células Intersticiales de Cajal , Humanos , Colon/diagnóstico por imagen , Ultrasonografía
4.
Am J Physiol Regul Integr Comp Physiol ; 324(4): R446-R456, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36717167

RESUMEN

Deep breathing exercises are the second most used complementary health approach in the United States. Two heart rate variability (HRV) parameters, the root mean square of successive differences (RMSSD) and the respiratory sinus arrhythmia (RSA), are used to assess parasympathetic reactivity to deep breathing, but they are often not in agreement. Our purpose was to determine the cause of the disagreement. We investigated HRV parameters in 38 subjects during baseline, deep breathing, and recovery. Here we show that RMSSD as a measure of parasympathetic reactivity is unreliable; it does not reflect the increase in HRV during deep breathing as determined by RSA. We observed a decrease in RMSSD values despite a marked increase in HRV as determined by RSA and the standard deviation of normal heartbeat interval (SDNN) in healthy subjects and patients with functional bowel disorders. We show that RSA captures all aspects of HRV, whereas successive differences in heart rate intervals are only a small part of HRV, with decreasing variability during deep breathing in most subjects. We present a new measure of calculating RSA during deep breathing that may become an essential tool for researchers and clinicians. We also provide a unique visualization of the increased heart rate variability during deep breathing. Hence, RMSSD cannot be used to assess parasympathetic reactivity during deep breathing; using RSA is recommended. The use of RMSSD in previous influential studies may have led to erroneous conclusions about parasympathetic reactivity during deep breathing. Its continued use may undervalue the effects of the autonomic nervous system in slow deep breathing.


Asunto(s)
Sistema Nervioso Autónomo , Arritmia Sinusal Respiratoria , Humanos , Frecuencia Cardíaca/fisiología , Arritmia Sinusal , Menopausia
5.
Adv Exp Med Biol ; 1383: 205-212, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36587159

RESUMEN

The musculature of the gastrointestinal tract is a vast network of collaborating excitable cell types. Embedded throughout are the interstitial cells of Cajal (ICC) intertwined with enteric nerves. ICC sense external stimuli such as distention, mediate nerve impulses to smooth muscle cells, and provide rhythmic excitation of the musculature. Neural circuitry involving both the intrinsic and extrinsic autonomic nervous systems, in collaboration with the ICC, orchestrate an array of motor patterns that serve to provide mixing of content to optimize digestion and absorption, microbiome homeostasis, storage, transit, and expulsion. ICC are specialized smooth muscle cells that generate rhythmic depolarization to the musculature and so provide the means for peristaltic and segmenting contractions. Some motor patterns are purely myogenic, but a neural stimulus initiates most, further depolarizing the primary pacemaker cells and the musculature and/or initiating transient pacemaker activity in stimulus-dependent secondary ICC pacemaker cells. From stomach to rectum, ICC networks rhythmically provide tracks along which contractions advance.


Asunto(s)
Sistema Nervioso Entérico , Células Intersticiales de Cajal , Células Intersticiales de Cajal/fisiología , Sistema Nervioso Entérico/fisiología , Motilidad Gastrointestinal/fisiología , Músculo Liso/fisiología , Sistema Nervioso Autónomo
6.
Am J Physiol Gastrointest Liver Physiol ; 321(5): G552-G575, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34612070

RESUMEN

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.


Asunto(s)
Colon/patología , Enfermedades del Colon/patología , Defecación , Motilidad Gastrointestinal , Células Intersticiales de Cajal/patología , Animales , Sistema Nervioso Autónomo/fisiopatología , Colon/inervación , Colon/metabolismo , Enfermedades del Colon/metabolismo , Enfermedades del Colon/fisiopatología , Seudoobstrucción Colónica/metabolismo , Seudoobstrucción Colónica/patología , Seudoobstrucción Colónica/fisiopatología , Estreñimiento/metabolismo , Estreñimiento/patología , Estreñimiento/fisiopatología , Sistema Nervioso Entérico/fisiopatología , Incontinencia Fecal/metabolismo , Incontinencia Fecal/patología , Incontinencia Fecal/fisiopatología , Enfermedad de Hirschsprung/metabolismo , Enfermedad de Hirschsprung/patología , Enfermedad de Hirschsprung/fisiopatología , Humanos , Células Intersticiales de Cajal/metabolismo , Manometría
7.
Am J Physiol Gastrointest Liver Physiol ; 320(6): G1067-G1080, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33909507

RESUMEN

Contraction patterns of the human colon are rarely discussed from the perspective of its haustra. Colonic motility was analyzed in 21 healthy subjects using 84-sensor manometry catheters with 1-cm sensor spacing. Capsule endoscopy and manometry showed evidence of narrow rhythmic circular muscle contractions. X-ray images of haustra and sensor locations allowed us to identify manometry motor activity as intrahaustral activity. Two common motor patterns were observed that we infer to be associated with individual haustra: rhythmic pressure activity confined to a single sensor, and activity confined to a section of the colon of 3-6 cm length. Intrahaustral activity was observed by 3-4 sensors. Approximately 50% of the haustra were intermittently active for ∼30% of the time; 2,402 periods of haustral activity were analyzed. Intrahaustral activity showed rhythmic pressure waves, propagating in mixed direction, 5-30 mmHg in amplitude at a frequency of ∼3 cpm (range 2-6) or ∼12 cpm (range 7-15), or exhibiting a checkerboard segmentation pattern. Boundaries of the haustra showed rhythmic pressure activity with or without elevated baseline pressure. Active haustra often showed no boundary activity probably allowing transit to neighboring haustra. Haustral boundaries were seen at the same sensor for the 6- to 8-h study duration, indicating that they did not propagate, thereby likely contributing to continence. The present study elucidates the motility characteristics of haustral boundaries and the nature of intrahaustral motor patterns and paves the way for investigating their possible role in pathophysiology of defecation disorders.NEW & NOTEWORTHY Here, we present the first full characterization and quantification of motor patterns that we infer to be confined to single haustra, both intrahaustral activity and haustral boundary activity, in the human colon using high-resolution manometry. Haustral activity is intermittent but consistently present in about half of the haustra. Intrahaustral activity presents as a cyclic motor pattern of mixed propagation direction dominated by simultaneous pressure waves that can resolve into checkerboard segmentation, allowing for mixing, absorption, and stool formation.


Asunto(s)
Colon/fisiología , Motilidad Gastrointestinal/fisiología , Células Intersticiales de Cajal/fisiología , Adulto , Femenino , Voluntarios Sanos , Humanos , Masculino , Manometría , Persona de Mediana Edad , Contracción Muscular/fisiología , Adulto Joven
8.
Dig Dis Sci ; 66(10): 3516-3528, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33462748

RESUMEN

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.


Asunto(s)
Colon Sigmoide/fisiología , Recto/fisiología , Adulto , Colon Sigmoide/anatomía & histología , Femenino , Motilidad Gastrointestinal/fisiología , Humanos , Masculino , Manometría , Persona de Mediana Edad , Presión , Recto/anatomía & histología , Adulto Joven
9.
Dig Dis Sci ; 66(10): 3529-3541, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33462747

RESUMEN

BACKGROUND: Chronic constipation can have one or more of many etiologies, and a diagnosis based on symptoms is not sufficient as a basis for treatment, in particular surgery. AIM: To investigate the cause of chronic constipation in a patient with complete absence of spontaneous bowel movements. METHODS: High-resolution colonic manometry was performed to assess motor functions of the colon, rectum, the sphincter of O'Beirne and the anal sphincters. RESULTS: Normal colonic motor patterns were observed, even at baseline, but a prominent high-pressure zone at the rectosigmoid junction, the sphincter of O'Beirne, was consistently present. In response to high-amplitude propagating pressure waves (HAPWs) that were not consciously perceived, the sphincter and the anal sphincters would not relax and paradoxically contract, identified as autonomous dyssynergia. Rectal bisacodyl evoked marked HAPW activity with complete relaxation of the sphincter of O'Beirne and the anal sphincters, indicating that all neural pathways to generate the coloanal reflex were intact but had low sensitivity to physiological stimuli. A retrograde propagating cyclic motor pattern initiated at the sphincter of O'Beirne, likely contributing to failure of content to move into the rectum. CONCLUSIONS: Chronic constipation without the presence of spontaneous bowel movements can be associated with normal colonic motor patterns but a highly exaggerated pressure at the rectosigmoid junction: the sphincter of O'Beirne, and failure of this sphincter and the anal sphincters to relax associated with propulsive motor patterns. The sphincter of O'Beirne can be an important part of the pathophysiology of chronic constipation.


Asunto(s)
Ataxia/patología , Colon Sigmoide/patología , Estreñimiento/patología , Recto/patología , Canal Anal , Colon Sigmoide/anatomía & histología , Colon Sigmoide/inervación , Colon Sigmoide/fisiología , Estreñimiento/tratamiento farmacológico , Femenino , Motilidad Gastrointestinal , Humanos , Laxativos/uso terapéutico , Manometría , Persona de Mediana Edad , Recto/anatomía & histología , Recto/inervación , Recto/fisiología , Reflejo
10.
Am J Physiol Gastrointest Liver Physiol ; 318(4): G646-G660, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32068445

RESUMEN

Characterization of high-amplitude propagating pressure waves (HAPWs or HAPCs) plays a key role in diagnosis of colon dysmotility using any type of colonic manometry. With the introduction of high-resolution manometry, more insight is gained into this most prominent propulsive motor pattern. Here, we use a water-perfused catheter with 84 sensors with intervals between measuring points of 1 cm throughout the colon, for 6-8 h, in 19 healthy subjects. The catheter contained a balloon to evoke distention. We explored as stimuli a meal, balloon distention, oral prucalopride, and bisacodyl injection, with a goal to optimally evoke HAPWs. We developed a quantitative measure of HAPW activity, the "HAPW Index." Our protocol elicited 290 HAPWs. 21% of HAPWs were confined to the proximal colon with an average amplitude of 75.3 ± 3.3 mmHg and an average HAPW Index of 440 ± 58 mmHg·m·s. 29% of HAPWs started in the proximal colon and ended in the transverse or descending colon, with an average amplitude of 87.9 ± 3.1 mmHg and an average HAPW Index of 3,344 ± 356 mmHg·m·s. Forty-nine percent of HAPWs started and ended in the transverse or descending colon with an average amplitude of 109.3 ± 3.3 mmHg and an average HAPW Index of 2,071 ± 195 mmHg·m·s. HAPWs with and without simultaneous pressure waves (SPWs) initiated the colo-anal reflex, often abolishing 100% of anal sphincter pressure. Rectal bisacodyl and proximal balloon distention were the most optimal stimuli to evoke HAPWs. These measures now allow for a confident diagnosis of abnormal motility in patients with colonic motor dysfunction.NEW & NOTEWORTHY High-amplitude propagating pressure waves (HAPWs) were characterized using 84 sensors throughout the entire colon in healthy subjects, taking note of site of origin, site of termination, amplitude, and velocity, and to identify optimal stimuli to evoke HAPWs. Three categories of HAPWs were identified, including the associated colo-anal reflex. Proximal balloon distention and rectal bisacodyl were recognized as reliable stimuli for evoking HAPWs, and a HAPW Index was devised to quantify this essential colonic motor pattern.


Asunto(s)
Colon/fisiología , Motilidad Gastrointestinal/fisiología , Contracción Muscular/fisiología , Adulto , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Adulto Joven
11.
Appl Microbiol Biotechnol ; 103(1): 201-209, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30421107

RESUMEN

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.


Asunto(s)
Ácido Cítrico/metabolismo , Microbiología Industrial/métodos , Ingeniería Metabólica/métodos , Aspergillus niger/genética , Aspergillus niger/metabolismo , Carbono/metabolismo , Fermentación , Microbiología Industrial/economía , Microorganismos Modificados Genéticamente/metabolismo , Mutación , Yarrowia/genética , Yarrowia/metabolismo
12.
Molecules ; 23(7)2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30036952

RESUMEN

Myrica rubra (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-O-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.


Asunto(s)
Antocianinas/farmacología , Myrica/química , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Extractos Vegetales/farmacología , Daño por Reperfusión/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Animales , Antocianinas/química , Biomarcadores , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Humanos , Concentración de Iones de Hidrógeno , Masculino , Ratones , Modelos Biológicos , Estructura Molecular , Extractos Vegetales/química , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patología
13.
Am J Physiol Gastrointest Liver Physiol ; 310(3): G181-92, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26635318

RESUMEN

The rabbit proximal colon is similar in structure to the human colon. Our objective was to study interactions of different rhythmic motor patterns focusing on haustral boundary contractions, which create the haustra, using spatiotemporal mapping of video recordings. Haustral boundary contractions were seen as highly rhythmic circumferential ring contractions that propagated slowly across the proximal colon, preferentially but not exclusively in the anal direction, at ∼0.5 cycles per minute; they were abolished by nerve conduction blockers. When multiple haustral boundary contractions propagated in the opposite direction, they annihilated each other upon encounter. Ripples, myogenic propagating ring contractions at ∼9 cycles per min, induced folding and unfolding of haustral muscle folds, creating an anarchic appearance of contractile activity, with different patterns in the three intertaenial regions. Two features of ripple activity were prominent: frequent changes in propagation direction and the occurrence of dislocations showing a frequency gradient with the highest intrinsic frequency in the distal colon. The haustral boundary contractions showed an on/off/on/off pattern at the ripple frequency, and the contraction amplitude at any point of the colon showed waxing and waning. The haustral boundary contractions are therefore shaped by interaction of two pacemaker activities hypothesized to occur through phase-amplitude coupling of pacemaker activities from interstitial cells of Cajal of the myenteric plexus and of the submuscular plexus. Video evidence shows the unique role haustral folds play in shaping contractile activity within the haustra. Muscarinic agents not only enhance the force of contraction, they can eliminate one and at the same time induce another neurally dependent motor pattern.


Asunto(s)
Colon/fisiología , Músculo Liso/fisiología , Animales , Betanecol/farmacología , Relojes Biológicos/fisiología , Colon/anatomía & histología , Colon/citología , Fenómenos Electrofisiológicos/fisiología , Femenino , Motilidad Gastrointestinal/efectos de los fármacos , Técnicas In Vitro , Masculino , Agonistas Muscarínicos/farmacología , Contracción Muscular/fisiología , Neostigmina/farmacología , Conejos , Tetrodotoxina/farmacología
15.
Am J Physiol Cell Physiol ; 309(6): C403-14, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26135802

RESUMEN

Phase-amplitude coupling of two pacemaker activities of the small intestine, the omnipresent slow wave activity generated by interstitial cells of Cajal of the myenteric plexus (ICC-MP) and the stimulus-dependent rhythmic transient depolarizations generated by ICC of the deep muscular plexus (ICC-DMP), was recently hypothesized to underlie the orchestration of the segmentation motor pattern. The aim of the present study was to increase our understanding of phase-amplitude coupling through modeling. In particular the importance of propagation velocity of the ICC-DMP component was investigated. The outcome of the modeling was compared with motor patterns recorded from the rat or mouse intestine from which propagation velocities within the different patterns were measured. The results show that the classical segmentation motor pattern occurs when the ICC-DMP component has a low propagation velocity (<0.05 cm/s). When the ICC-DMP component has a propagation velocity in the same order of magnitude as that of the slow wave activity (∼1 cm/s), cluster type propulsive activity occurs which is in fact the dominant propulsive activity of the intestine. Hence, the only difference between the generation of propagating cluster contractions and the Cannon-type segmentation motor pattern is the propagation velocity of the low-frequency component, the rhythmic transient depolarizations originating from the ICC-DMP. Importantly, the proposed mechanism explains why both motor patterns have distinct rhythmic waxing and waning of the amplitude of contractions. The hypothesis is brought forward that the velocity is modulated by neural regulation of gap junction conductance within the ICC-DMP network.


Asunto(s)
Relojes Biológicos/fisiología , Células Intersticiales de Cajal/fisiología , Intestino Delgado/fisiología , Plexo Mientérico/fisiología , Plexo Submucoso/fisiología , Animales , Electrofisiología/métodos , Femenino , Masculino , Ratones , Músculo Liso/fisiología , Análisis de la Onda del Pulso/métodos , Ratas , Ratas Sprague-Dawley
16.
Curr Gastroenterol Rep ; 16(1): 363, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24408748

RESUMEN

The basic science and clinical interest in the networks of interstitial cells of Cajal (ICC) keep growing, and here, research from 2010 to mid-2013 is highlighted. High-resolution gastrointestinal manometry and spatiotemporal mapping are bringing exciting new insights into motor patterns, their function and their myogenic and neurogenic origins, as well as the role of ICC. Critically important knowledge is emerging on the partaking of PDGFRα+ cells in ICC pacemaker networks. Evidence is emerging that ICC and PDGFRα+ cells have unique direct roles in muscle innervation. Chronic constipation is associated with loss and injury to ICC, which is stimulating extensive research into maintenance and repair of ICC after injury. In gastroparesis, high-resolution electrical and mechanical studies are beginning to elucidate the pathophysiological role of ICC and the pacemaker system in this condition. Receptors and ion channels that play a role in ICC function are being discovered and characterized, which paves the way for pharmacological interventions in gut motility disorders through ICC.


Asunto(s)
Células Intersticiales de Cajal/fisiología , Relojes Biológicos/fisiología , Colon/fisiología , Sistema Nervioso Entérico/fisiología , Enfermedades Gastrointestinales/patología , Enfermedades Gastrointestinales/fisiopatología , Motilidad Gastrointestinal/fisiología , Gastroparesia/patología , Gastroparesia/fisiopatología , Humanos , Músculo Liso/inervación
17.
Gastroenterol Nurs ; 37(4): 289-98, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25078043

RESUMEN

A significant number of patients with irritable bowel syndrome hold misconceptions about their disease and experience more impaired quality of life compared with the general population and people suffering from other chronic diseases. This study was designed to explore the effectiveness of a structured educational intervention on disease-related misconceptions and quality of life in patients with irritable bowel syndrome in Wuhan, China. A convenience sample of 23 patients with irritable bowel syndrome participated in an educational program that consisted of 4 weekly sessions in a group setting. Instruments, including an irritable bowel syndrome-related misconception scale and irritable bowel syndrome quality-of-life scale, were used for evaluation at baseline and 3 months after the sessions. Three months after the structured educational intervention, the score for irritable bowel syndrome-related misconception was significantly decreased (p < .001), and the score for irritable bowel syndrome quality of life was significantly improved (p < .001). We conclude that the structured educational intervention seems to be a proper method to reduce the disease-related misconceptions and improve the quality of life in patients with irritable bowel syndrome. Planning and implementing such clinical education programs will be helpful in decreasing disease-related misconceptions and promoting quality of life in patients with irritable bowel syndrome.


Asunto(s)
Síndrome del Colon Irritable/psicología , Educación del Paciente como Asunto/métodos , Calidad de Vida , Adulto , Femenino , Humanos , Síndrome del Colon Irritable/terapia , Masculino , Persona de Mediana Edad
18.
Sci Rep ; 14(1): 8436, 2024 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600141

RESUMEN

The purpose of this study was to establish an integrated predictive model that combines clinical features, DVH, radiomics, and dosiomics features to predict RIHT in patients receiving tomotherapy for nasopharyngeal carcinoma. Data from 219 patients with nasopharyngeal carcinoma were randomly divided into a training cohort (n = 175) and a test cohort (n = 44) in an 8:2 ratio. RIHT is defined as serum thyroid-stimulating hormone (TSH) greater than 5.6 µU/mL, with or without a decrease in free thyroxine (FT4). Clinical features, 27 DVH features, 107 radiomics features and 107 dosiomics features were extracted for each case and included in the model construction. The least absolute shrinkage and selection operator (LASSO) regression method was used to select the most relevant features. The eXtreme Gradient Boosting (XGBoost) was then employed to train separate models using the selected features from clinical, DVH, radiomics and dosiomics data. Finally, a combined model incorporating all features was developed. The models were evaluated using receiver operating characteristic (ROC) curves and decision curve analysis. In the test cohort, the area under the receiver operating characteristic curve (AUC) for the clinical, DVH, radiomics, dosiomics and combined models were 0.798 (95% confidence interval [CI], 0.656-0.941), 0.673 (0.512-0.834), 0.714 (0.555-0.873), 0.698 (0.530-0.848) and 0.842 (0.724-0.960), respectively. The combined model exhibited higher AUC values compared to other models. The decision curve analysis demonstrated that the combined model had superior clinical utility within the threshold probability range of 1% to 79% when compared to the other models. This study has successfully developed a predictive model that combines multiple features. The performance of the combined model is superior to that of single-feature models, allowing for early prediction of RIHT in patients with nasopharyngeal carcinoma after tomotherapy.


Asunto(s)
Hipotiroidismo , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidad Modulada/efectos adversos , Aprendizaje Automático , Neoplasias Nasofaríngeas/radioterapia , Estudios Retrospectivos
19.
Dig Dis Sci ; 63(11): 2820-2822, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29881907
20.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(12): 1636-41, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24517060

RESUMEN

OBJECTIVE: To evaluate the clinical efficacy and safety of treatment of chronic primary glomerulopathy (CPG) patients of Shen deficiency and dampness heat syndrome (SDDHS) by Yishen Qingli Granule (YQG) combined with low-dose Tripterygium Wilfordii multiglycoside Tablet (TWT). METHODS: Totally 231 CPG patients of SDDHS were enrolled in this study (including 60 patients from First Affiliated Hospital of Nanjing University of Chinese Medicine, 58 from First Affiliated Hospital of Nanjing Medical University, 46 from Xinqiao Hospital of Third Military Medical University, 35 from First Affiliated Hospital of Guangzhou University of Chinese Medicine, 14 from First Affiliated Hospital of Soochow University, and 18 from Wuxi Affiliated Hospital of Nanjing University of Chinese Medicine). They were randomly assigned to the control group (116 cases) and the trial group (115 cases) according to block group method. There were 217 cases in the safety analysis set (109 cases in the trial group vs 108 cases in the control group), and 203 cases in the full analysis set (99 cases in the trial group vs 104 cases in the control group). All patients received basic treatment such as ACEI/ARB. Furthermore, YQG (consisting of raw astragalus 10 g, prepared Polygonum Multiflorum 10 g, Pyrrosia 10 g, 1.5 g each package, containing 10 g of crude drugs) was additionally given to patients in the trial group, each package, twice daily. The TWT (10 mg) was given, twice a day. The TWT dose was adjusted according to 24 h urinary total protein (UTP). The placebos of YQG and TWT were administered to those in the control group. The treatment course consisted of 24 weeks and the follow-up visit lasted for 24 weeks. The biochemical indices were observed before and after treatment including 24 h UTP, urine red cell count (U(RBC)), renal functions (BUN, SCr), blood routine test (WBC), and liver functions (SGPT, SGOT). Reverse reactions such as gastrointestinal discomfort, skin rash, and irregular menstruation were also observed. RESULTS: Compared with the control group, the total effective rate was better in the trial group (82.83% vs 61.54%, P < 0.01). Results of stratified comparison of UTP showed better efficacy in the trial group (0.8-3.0 g/24 h, P < 0.01). The UTP decline occurred in the trial group after 8 weeks of treatment, with stable action, showing statistical difference when compared with the control group (P < 0.01). In the trial group, U(RBC) level decreased after treatment but changed more significantly. But there was no statistical difference in the changes when compared with the control group (P > 0.05). After treatment, there were no statistical difference in safety indicators such as WBC, SGPT, and SGOT between the two groups after treatment (P > 0.05). CONCLUSION: On the basis of basic treatment such as ACEI/ARB, application of YQG combined with low-dose TWT had better effect in controlling proteinuria of CPG patients, and could help stabilizing their conditions with less adverse reactions.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Enfermedades Renales/diagnóstico , Enfermedades Renales/tratamiento farmacológico , Fitoterapia/métodos , Adulto , Femenino , Humanos , Glomérulos Renales/patología , Masculino , Medicina Tradicional China , Persona de Mediana Edad , Resultado del Tratamiento , Tripterygium
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