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1.
Neurogastroenterol Motil ; 32(7): e13926, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32478910

RESUMO

BACKGROUND: The COVID-19 pandemic, declared by WHO on March 13, 2020, had a major global impact on the healthcare system and services. In the acute phase, the presence of the SARS-CoV-2 virus in the aerodigestive tract limited activities in the gastroenterology clinic and procedures to emergencies only. Motility and function testing was interrupted and as we enter the recovery phase, restarting these procedures requires a safety-focused approach with adequate infection prevention for patients and healthcare professionals. METHODS: We summarized knowledge on the presence of the SARS-CoV-2 virus in the aerodigestive tract and the risk of spread with motility and functional testing. We surveyed 39 European centers documenting how the pandemic affected activities and which measures they are considering for restarting these measurements. We propose recommendations based on current knowledge as applied in our center. RESULTS: Positioning of catheters for gastrointestinal motility tests carries a concern for aerosol-borne infection of healthcare workers. The risk is low with breath tests. The surveyed centers stopped almost all motility and function tests from the second half of March. The speed of restarting and the safety measures taken varied highly. CONCLUSIONS AND INFERENCES: Based on these findings, we provided recommendations and practical relevant information for motility and function test procedures in the COVID-19 pandemic era, to guarantee a high-quality patient care with adequate infection prevention.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Gastroenterologia/métodos , Motilidade Gastrointestinal/fisiologia , Pandemias , Pneumonia Viral/epidemiologia , Recuperação de Função Fisiológica/fisiologia , Infecções por Coronavirus/prevenção & controle , Europa (Continente)/epidemiologia , Gastroenterologia/normas , Pessoal de Saúde/normas , Humanos , Pandemias/prevenção & controle , Assistência ao Paciente/métodos , Assistência ao Paciente/normas , Pneumonia Viral/prevenção & controle , Guias de Prática Clínica como Assunto/normas , Roupa de Proteção/normas , Inquéritos e Questionários
2.
Neurogastroenterol Motil ; 32(7): e13930, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32525249

RESUMO

BACKGROUND: During the peak of the COronaVIrus Disease 2019 (COVID-19) pandemic, care for patients with gastrointestinal motility and functional disorders was largely suspended. In the recovery phases of the pandemic, non-urgent medical care is resumed, but there is a lack of guidance for restarting and safely conducting motility and function testing. Breath tests and insertion of manometry and pH-monitoring probes carry a risk of SARS-CoV-2 spread through droplet formation. METHODS: A panel of experts from the European Society for Neurogastroenterology and Motility (ESNM) evaluated emerging national and single-center recommendations to provide the best current evidence and a pragmatic approach to ensure the safe conduct of motility and function testing for both healthcare professionals and patients. RESULTS: At a general level, this involves evaluation of the urgency of the procedure, evaluation of the infectious risk associated with the patient, the investigation and the healthcare professional(s) involved, provision of the test planning and test units, education and training of staff, and use of personnel protection equipment. Additional guidance is provided for specific procedures such as esophageal manometry, pH monitoring, and breath tests. CONCLUSIONS AND INFERENCES: The ESNM guidelines provide pragmatic and appropriate guidance for the safe conduct of motility and function testing in the COVID-19 pandemic and early recovery phase.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Gastroenterologia/normas , Motilidade Gastrointestinal/fisiologia , Neurologia/normas , Pneumonia Viral/epidemiologia , Guias de Prática Clínica como Assunto/normas , Recuperação de Função Fisiológica/fisiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Europa (Continente)/epidemiologia , Prova Pericial/métodos , Prova Pericial/normas , Pessoal de Saúde/normas , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Roupa de Proteção/normas , Sociedades Médicas/normas
3.
J Vis Exp ; (159)2020 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-32449718

RESUMO

Most animals use the gastrointestinal (GI) tract to digest food. The movement of the ingested food in the GI tract is essential for nutrient absorption. Disordered GI motility and gastric emptying cause multiple diseases and symptoms. As a powerful genetic model organism, Drosophila can be used in GI motility research. The Drosophila crop is an organ that contracts and moves food into the midgut for further digestion, functionally similar to a mammalian stomach. Presented is a protocol to study Drosophila crop motility using simple measurement tools. A method for counting crop contractions to evaluate crop motility and a method for detecting the distribution of food dyed blue between the crop and gut using a spectrophotometer to investigate the effect of the crop on food passaging is described. The method was used to detect the difference in crop motility between control and nprl2 mutant flies. This protocol is both cost-efficient and highly sensitive to crop motility.


Assuntos
Drosophila/patogenicidade , Motilidade Gastrointestinal/fisiologia , Animais , Análise de Alimentos , Masculino
4.
PLoS One ; 15(4): e0232023, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32352981

RESUMO

INTRODUCTION: Intestinal atresia is a rare congenital affliction that is often associated with severe bacterial infections despite adequate neonatal surgery. Previous studies have focused on enteric nervous system variations. We hypothesized that epithelial systems (ES) may also be involved in the pathophysiology of postnatal disorders. MATERIALS AND METHODS: Global gene expression was measured by transcriptomic analysis in a rat model of induced intestinal atresia. The analyses then focused on genes involved in ES (enterocytes and goblet cells). Rat fetus small intestines at various stages of development (ED15, ED17, ED19, and ED21, n = 22), were used as non-operated controls and compared to the upper and lower segments of rat fetus small intestines with an induced atresia (n = 14; ligature at ED18). The pattern of gene expression was then confirmed by histochemistry, electron microscopy, and RT-qPCR. RESULTS: From ED15 to ED21, the expression of several genes exhibited a physiological increase of ES markers, with a significant increase at the end of gestation. The operated embryos exhibited significantly higher variations of gene expression in the proximal segment than in the distal segment in terms of absorption and the epithelial barrier. An increase in goblet cells and markers was observed in the proximal segment compared to the controls. CONCLUSION: Fetal intestinal obstruction accelerates maturation in the proximal segment and disrupts the intestinal wall in the distal segment, with a decrease in the number of mucosal cells. Moreover, the epithelial cells underwent significant changes, supporting the notion that intestinal disorders involve more than the ENS.


Assuntos
Atresia Intestinal/genética , Atresia Intestinal/fisiopatologia , Mucosa Intestinal/fisiopatologia , Animais , Modelos Animais de Doenças , Sistema Nervoso Entérico , Enterócitos/metabolismo , Células Epiteliais/metabolismo , Feminino , Feto , Motilidade Gastrointestinal/fisiologia , Perfilação da Expressão Gênica/métodos , Células Caliciformes/metabolismo , Obstrução Intestinal/fisiopatologia , Intestinos/fisiopatologia , Gravidez , Ratos , Ratos Wistar , Transcriptoma/genética
5.
Med Sci Monit ; 26: e919815, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-32248203

RESUMO

BACKGROUND Fructus aurantii is a flavonoid derived from Citrus aurantium (bitter orange) that is used in traditional Chinese medicine (TCM) to treat gastric motility disorders. This study aimed to investigate the effects of low-dose and high-dose decoctions of Fructus aurantii in a rat model of functional dyspepsia (FD). MATERIAL AND METHODS Sprague-Dawley rats (n=90) were divided into nine study groups: the control group, the FD model group, the domperidone-treated (Domp) group, the low-dose raw Fructus aurantii (FA-L) group, the high-dose raw Fructus aurantii (FA-H) group, the low-dose Fructus aurantii with stir-fried wheat bran (Bran-L) group, the high-dose Fructus aurantii with stir-fried wheat bran (Bran-H) group, the low-dose Fructus aurantii with stir-fried wheat bran and honey (Honey-L) group, and the high-dose Fructus aurantii with stir-fried wheat bran and honey (Honey-H) group. The FD rat model was established by semi-starvation, followed by tail damping, stimulation, and forced exercise with fatigue. Change in weight, rate of gastric emptying and intestinal propulsion, and serum levels of leptin, motilin, vasoactive intestinal peptide (VIP), gastrin, calcitonin gene-related peptide (CGRP), ghrelin, and cholecystokinin were compared between the groups. RESULTS In the FD model group, weight, rate of gastric emptying and intestinal propulsion significantly decreased, the expression of leptin, VIP and CGRP increased, and expression of motilin, gastrin, ghrelin, and cholecystokinin significantly decreased. Treatment with low-dose Fructus aurantii with stir-fried wheat bran significantly reversed these effects. CONCLUSIONS In the rat model of FD, low-dose Fructus aurantii with stir-fried wheat bran increased gastrointestinal motility and gastrointestinal hormone levels.


Assuntos
Citrus/química , Dispepsia/tratamento farmacológico , Animais , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Esvaziamento Gástrico/fisiologia , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Medicina Tradicional Chinesa , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
6.
PLoS Biol ; 18(3): e3000661, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32196484

RESUMO

Some of the densest microbial ecosystems in nature thrive within the intestines of humans and other animals. To protect mucosal tissues and maintain immune tolerance, animal hosts actively sequester bacteria within the intestinal lumen. In response, numerous bacterial pathogens and pathobionts have evolved strategies to subvert spatial restrictions, thereby undermining immune homeostasis. However, in many cases, it is unclear how escaping host spatial control benefits gut bacteria and how changes in intestinal biogeography are connected to inflammation. A better understanding of these processes could uncover new targets for treating microbiome-mediated inflammatory diseases. To this end, we investigated the spatial organization and dynamics of bacterial populations within the intestine using larval zebrafish and live imaging. We discovered that a proinflammatory Vibrio symbiont native to zebrafish governs its own spatial organization using swimming motility and chemotaxis. Surprisingly, we found that Vibrio's motile behavior does not enhance its growth rate but rather promotes its persistence by enabling it to counter intestinal flow. In contrast, Vibrio mutants lacking motility traits surrender to host spatial control, becoming aggregated and entrapped within the lumen. Consequently, nonmotile and nonchemotactic mutants are susceptible to intestinal expulsion and experience large fluctuations in absolute abundance. Further, we found that motile Vibrio cells induce expression of the proinflammatory cytokine tumor necrosis factor alpha (TNFα) in gut-associated macrophages and the liver. Using inducible genetic switches, we demonstrate that swimming motility can be manipulated in situ to modulate the spatial organization, persistence, and inflammatory activity of gut bacterial populations. Together, our findings suggest that host spatial control over resident microbiota plays a broader role in regulating the abundance and persistence of gut bacteria than simply protecting mucosal tissues. Moreover, we show that intestinal flow and bacterial motility are potential targets for therapeutically managing bacterial spatial organization and inflammatory activity within the gut.


Assuntos
Microbioma Gastrointestinal/fisiologia , Motilidade Gastrointestinal/fisiologia , Intestinos/patologia , Locomoção/fisiologia , Animais , Animais Geneticamente Modificados , Quimiotaxia/genética , Quimiotaxia/fisiologia , Inflamação , Intestinos/microbiologia , Locomoção/genética , Macrófagos/metabolismo , Interações Microbianas , Mutação , Fator de Necrose Tumoral alfa/metabolismo , Vibrio/genética , Vibrio/fisiologia , Peixe-Zebra/microbiologia , Peixe-Zebra/fisiologia
7.
Aliment Pharmacol Ther ; 51(8): 760-769, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32128859

RESUMO

BACKGROUND: Managing chronic constipation is challenging as patients frequently remain dissatisfied with laxative treatments. Novel studies using transabdominal electrical interferential therapy in children have shown benefit but there are inadequate adult studies. AIM: To examine the effects of transabdominal interferential stimulation on bowel symptoms and quality of life in women with refractory constipation. METHODS: In a single-blind, randomised, sham-controlled pilot study, women aged ≥18 years with refractory constipation were randomised to receive interferential stimulation (with crossing of electric currents) or a novel sham stimulation (with no crossing of currents) for 1 hour a day for 6 weeks. Primary outcome was the number of patients with ≥3 spontaneous bowel movements/week. Secondary endpoints included change in PAC-SYM (Patient Assessment of Constipation-SYMptoms), PAC-QOL (Patient Assessment of Constipation-Quality of Life) and an overall symptom severity score (measured at baseline, mid time point of stimulation, end of treatment and 3 months after cessation of treatment). RESULTS: Interferential therapy (n = 17) met the primary outcome in 9(53%) compared with 2(12%) with sham therapy (n = 16) (P = 0.02). Interferential therapy resulted in reductions in PAC-SYM (P = 0.03) and overall symptom scores (P = 0.05). Laxative use more than halved in 66% with interferential therapy compared with 14% with sham therapy (P = 0.01). Significant improvements in symptom outcomes were maintained at 3 months. There were no treatment-related adverse effects. CONCLUSION: Transabdominal interferential electrical stimulation is effective in reducing constipation in adult women. Three months after therapy, response is maintained and quality of life improved. Not allowing currents to cross intra-abdominally was an effective placebo. (Australianclinicaltrials.gov.au ACTRN12614000736640).


Assuntos
Constipação Intestinal/terapia , Terapia por Estimulação Elétrica/métodos , Abdome , Adolescente , Adulto , Idoso , Austrália , Constipação Intestinal/fisiopatologia , Defecação/fisiologia , Feminino , Motilidade Gastrointestinal/fisiologia , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Placebos , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
8.
Curr Gastroenterol Rep ; 22(3): 14, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32078071

RESUMO

PURPOSE OF REVIEW: Small bowel dysmotility is a broad heterogeneous term that encompasses a wide range of gastrointestinal disorders resulting from abnormal gut motility. Chronic intestinal pseudo-obstruction (CIPO) is a severe, rare, and complex small bowel motility disorder at the extreme end of this spectrum. It is characterized by failure of the intestinal tract to propel contents, which results in signs and symptoms of bowel obstruction albeit in the absence of any obstructive lesion(s). In this article, we discuss up-to-date diagnostic techniques, management options, and histopathological findings in CIPO. RECENT FINDINGS: We will emphasize the latest diagnostic methodologies and therapeutic options as well as enteric histopathologic abnormalities in patients with CIPO. CIPO continues to be a clinical challenge. Several novel pharmacological agents hold promise including gastrointestinal hormone agonists and prokinetics. Furthermore, histopathologic findings may help guide therapy and provide further prognostic significance. At present, nutritional support, symptom management, and avoidance of long-term complications are the mainstay of treatment in CIPO.


Assuntos
Motilidade Gastrointestinal/fisiologia , Pseudo-Obstrução Intestinal/diagnóstico , Pseudo-Obstrução Intestinal/terapia , Intestino Delgado/fisiopatologia , Doença Crônica , Humanos , Íleus/diagnóstico , Íleus/etiologia , Íleus/fisiopatologia , Íleus/terapia , Pseudo-Obstrução Intestinal/etiologia , Pseudo-Obstrução Intestinal/fisiopatologia , Apoio Nutricional
10.
Am J Physiol Gastrointest Liver Physiol ; 318(4): G646-G660, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32068445

RESUMO

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.


Assuntos
Colo/fisiologia , Motilidade Gastrointestinal/fisiologia , Contração Muscular/fisiologia , Adulto , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Adulto Jovem
11.
Expert Rev Gastroenterol Hepatol ; 14(2): 103-111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31996050

RESUMO

Introduction: Motilin was first alluded to nearly a century ago. But it remains a rather abstruse peptide, in the shadow of its younger but more lucid 'cousin' ghrelin.Areas covered: The review aimed to bring to the fore multifarious aspects of motilin research with a view to aiding prioritization of future studies on this gastrointestinal peptide.Expert opinion: Growing evidence indicates that rodents (mice, rats, guinea pigs) do not have functional motilin system and, hence, studies in these species are likely to have a minimal translational impact. Both the active peptide and motilin receptor were initially localized to the upper gastrointestinal tract only but more recently - also to the brain (in both humans and other mammals with functional motilin system). Motilin is now indisputably implicated in interdigestive contractile activity of the gastrointestinal tract (in particular, gastric phase III of the migrating motor complex). Beyond this role, evidence is building that there is a cross-talk between motilin system and the brain-pancreas axis, suggesting that motilin exerts not only contractile but also orexigenic and insulin secretagogue actions.


Assuntos
Encéfalo/fisiologia , Trato Gastrointestinal/fisiologia , Motilina/fisiologia , Pâncreas/fisiologia , Animais , Motilidade Gastrointestinal/fisiologia , Grelina/fisiologia , Humanos , Fome/fisiologia , Insulina/fisiologia , Complexo Mioelétrico Migratório/fisiologia , Receptor Cross-Talk/fisiologia , Receptores dos Hormônios Gastrointestinais/fisiologia , Receptores de Neuropeptídeos/fisiologia , Transdução de Sinais/fisiologia
12.
PLoS One ; 15(1): e0227781, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978146

RESUMO

BACKGROUND: Memantine, currently available for the treatment of Alzheimer's disease, is an uncompetitive antagonist of the N-methyl-D-aspartate type of glutamate receptors. Under normal physiologic conditions, these unstimulated receptor ion channels are blocked by magnesium ions, which are displaced after agonist-induced depolarization. In humans, memantine administration is associated with different gastrointestinal dysmotility side effects (vomiting, diarrhoea, constipation, motor-mediated abdominal pain), thus limiting its clinical use. Mechanism of these motility disorders has not been clarified yet. Pigs can be used in various preclinical experiments due to their relatively very similar gastrointestinal functions compared to humans. The aim of this study was to evaluate the impact of a single and repeated doses of memantine on porcine gastric myoelectric activity evaluated by means of electrogastrography (EGG). METHODS: Six adult female experimental pigs (Sus scrofa f. domestica, mean weight 41.7±5.0 kg) entered the study for two times. The first EGG was recorded after a single intragastric dose of memantine (20 mg). In the second part, EGG was accomplished after 7-day intragastric administration (20 mg per day). All EGG recordings were performed under general anaesthesia. Basal (15 minutes) and study recordings (120 minutes) were accomplished using an EGG stand (MMS, Enschede, the Netherlands). Running spectral analysis based on Fourier transform was used. Results were expressed as dominant frequency of gastric slow waves (DF) and power analysis (areas of amplitudes). RESULTS: Single dose of memantine significantly increased DF, from basic values (1.65±1.05 cycles per min.) to 2.86 cpm after 30 min. (p = 0.008), lasting till 75 min. (p = 0.014). Basal power (median 452; inter-quartile range 280-1312 µV^2) raised after 15 min. (median 827; IQR 224-2769; p = 0.386; NS), lasting next 30 min. Repetitively administrated memantine caused important gastric arrhythmia. Basal DF after single and repeated administration was not different, however, a DF increase in the second part was more prominent (up to 3.18±2.16 after 15 and 30 min., p<0.001). In comparison with a single dose, basal power was significantly higher after repetitively administrated memantine (median 3940; IQR 695-15023 µV^2; p<0.001). Next dose of 20 mg memantine in the second part induced a prominent drop of power after 15 min. (median 541; IQR 328-2280 µV^2; p<0.001), lasting till 120 min. (p<0.001). CONCLUSIONS: Both single and repeated doses of memantine increased DF. Severe gastric arrhythmia and long-lasting low power after repeated administration might explain possible gastric dysmotility side effects in the chronic use of memantine.


Assuntos
Antagonistas de Aminoácidos Excitatórios/efeitos adversos , Gastroenteropatias/induzido quimicamente , Motilidade Gastrointestinal/efeitos dos fármacos , Memantina/efeitos adversos , Estômago/efeitos dos fármacos , Administração Oral , Doença de Alzheimer/tratamento farmacológico , Animais , Modelos Animais de Doenças , Eletromiografia , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Feminino , Gastroenteropatias/diagnóstico , Gastroenteropatias/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Humanos , Memantina/administração & dosagem , Estômago/fisiopatologia , Sus scrofa
13.
Gastroenterology ; 158(5): 1232-1249.e3, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31945360

RESUMO

With a worldwide prevalence of 15%, chronic constipation is one of the most frequent gastrointestinal diagnoses made in ambulatory medicine clinics, and is a common source cause for referrals to gastroenterologists and colorectal surgeons in the United States. Symptoms vary among patients; straining, incomplete evacuation, and a sense of anorectal blockage are just as important as decreased stool frequency. Chronic constipation is either a primary disorder (such as normal transit, slow transit, or defecatory disorders) or a secondary one (due to medications or, in rare cases, anatomic alterations). Colonic sensorimotor disturbances and pelvic floor dysfunction (such as defecatory disorders) are the most widely recognized pathogenic mechanisms. Guided by efficacy and cost, management of constipation should begin with dietary fiber supplementation and stimulant and/or osmotic laxatives, as appropriate, followed, if necessary, by intestinal secretagogues and/or prokinetic agents. Peripherally acting µ-opiate antagonists are another option for opioid-induced constipation. Anorectal tests to evaluate for defecatory disorders should be performed in patients who do not respond to over-the-counter agents. Colonic transit, followed if necessary with assessment of colonic motility with manometry and/or a barostat, can identify colonic dysmotility. Defecatory disorders often respond to biofeedback therapy. For specific patients, slow-transit constipation may necessitate a colectomy. No studies have compared inexpensive laxatives with newer drugs with different mechanisms. We review the mechanisms, evaluation, and management of chronic constipation. We discuss the importance of meticulous analyses of patient history and physical examination, advantages and disadvantages of diagnostic testing, guidance for individualized treatment, and management of medically refractory patients.


Assuntos
Constipação Intestinal/terapia , Defecação/fisiologia , Motilidade Gastrointestinal/fisiologia , Doença Crônica/epidemiologia , Doença Crônica/terapia , Colo/diagnóstico por imagem , Colo/inervação , Colo/metabolismo , Colo/fisiopatologia , Constipação Intestinal/diagnóstico , Constipação Intestinal/epidemiologia , Constipação Intestinal/etiologia , Defecografia , Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Exame Retal Digital , Eletromiografia , Motilidade Gastrointestinal/efeitos dos fármacos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatologia , Laxantes/administração & dosagem , Imagem por Ressonância Magnética , Manometria , Diafragma da Pelve/inervação , Diafragma da Pelve/fisiopatologia , Prevalência , Receptores Opioides mu/antagonistas & inibidores , Receptores Opioides mu/metabolismo , Reto/diagnóstico por imagem , Reto/inervação , Reto/metabolismo , Reto/fisiopatologia , Secretagogos/administração & dosagem
17.
Am J Physiol Gastrointest Liver Physiol ; 318(2): G225-G243, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31813235

RESUMO

The interstitial cells of Cajal associated with the myenteric plexus (ICC-MP) are a network of coupled oscillators in the small intestine that generate rhythmic electrical phase waves leading to corresponding waves of contraction, yet rhythmic action potentials and intercellular calcium waves have been recorded from c-kit-mutant mice that lack the ICC-MP, suggesting that there may be a second pacemaker network. The gap junction blocker carbenoxolone induced a "pinstripe" motor pattern consisting of rhythmic "stripes" of contraction that appeared simultaneously across the intestine with a period of ~4 s. The infinite velocity of these stripes suggested they were generated by a coupled oscillator network, which we call X. In c-kit mutants rhythmic contraction waves with the period of X traveled the length of the intestine, before the induction of the pinstripe pattern by carbenoxolone. Thus X is not the ICC-MP and appears to operate under physiological conditions, a fact that could explain the viability of these mice. Individual stripes consisted of a complex pattern of bands of contraction and distension, and between stripes there could be slide waves and v waves of contraction. We hypothesized that these phenomena result from an interaction between X and the circular muscle that acts as a damped oscillator. A mathematical model of two chains of coupled Fitzhugh-Nagumo systems, representing X and circular muscle, supported this hypothesis. The presence of a second coupled oscillator network in the small intestine underlines the complexity of motor pattern generation in the gut.NEW & NOTEWORTHY Physiological experiments and a mathematical model indicate a coupled oscillator network in the small intestine in addition to the c-kit-expressing myenteric interstitial cells of Cajal. This network interacts with the circular muscle, which itself acts as a system of damped oscillators, to generate physiological contraction waves in c-kit (W) mutant mice.


Assuntos
Motilidade Gastrointestinal/fisiologia , Células Intersticiais de Cajal/fisiologia , Plexo Mientérico/fisiologia , Rede Nervosa/fisiologia , Potenciais de Ação/fisiologia , Animais , Sinalização do Cálcio/fisiologia , Carbenoxolona/farmacologia , Feminino , Intestino Delgado/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Neurológicos , Modelos Teóricos , Contração Muscular , Músculo Liso Vascular/efeitos dos fármacos , Mutação , Junção Neuromuscular , Proteínas Proto-Oncogênicas c-kit/genética
18.
Am J Physiol Gastrointest Liver Physiol ; 318(2): G244-G253, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31790272

RESUMO

The mechanisms underlying electrical rhythmicity in smooth muscle of the proximal colon are incompletely understood. Our aim was to identify patterns of electrical rhythmicity in smooth muscle of the proximal region of isolated whole mouse colon and characterize their mechanisms of origin. Two independent extracellular recording electrodes were used to record the patterns of electrical activity in smooth muscle of the proximal region of whole isolated mouse colon. Cross-correlation analysis was used to quantify spatial coordination of these electrical activities over increasing electrode separation distances. Four distinct neurogenic patterns of electrical rhythmicity were identified in smooth muscle of the proximal colon, three of which have not been identified and consisted of bursts of rhythmic action potentials at 1-2 Hz that were abolished by hexamethonium. These neurogenic patterns of electrical rhythmicity in smooth muscle were spatially and temporally synchronized over large separation distances (≥2 mm rosto-caudal axis). Myogenic slow waves could be recorded from the same preparations, but they showed poor spatial and temporal coordination over even short distances (≤1 mm rostro-caudal axis). It is not commonly thought that electrical rhythmicity in gastrointestinal smooth muscle is dependent upon the enteric nervous system. Here, we identified neurogenic patterns of electrical rhythmicity in smooth muscle of the proximal region of isolated mouse colon, which are dependent on synaptic transmission in the enteric nervous system. If the whole colon is studied in vitro, recordings can preserve novel neurogenic patterns of electrical rhythmicity in smooth muscle.NEW & NOTEWORTHY Previously, it has not often been thought that electrical rhythmicity in smooth muscle of the gastrointestinal tract is dependent upon the enteric nervous system. We identified patterns of electrical rhythmicity in smooth muscle of the mouse proximal colon that were abolished by hexamethonium and involved the temporal synchronization of smooth muscle membrane potential over large spatial fields. We reveal different patterns of electrical rhythmicity in colonic smooth muscle that are dependent on the ENS.


Assuntos
Colo/inervação , Colo/fisiologia , Motilidade Gastrointestinal/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Colo/efeitos dos fármacos , Eletrodos Implantados , Fenômenos Eletrofisiológicos/fisiologia , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/fisiologia , Feminino , Bloqueadores Ganglionares/farmacologia , Hexametônio/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
19.
Gastroenterol. hepatol. (Ed. impr.) ; 43: 0-0, 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-191021

RESUMO

El coronavirus del síndrome respiratorio agudo severo tipo 2 (conocido por sus siglas en inglés, SARS-CoV-2) ha sido responsable del brote de la denominada enfermedad por coronavirus de 2019 (COVID-19), que ha llegado a tener la consideración de pandemia. Las estrategias adoptadas para su prevención han incluido medidas de distanciamiento social, así como la modificación, reducción o interrupción de gran parte de la actividad sanitaria habitual. Esto ha afectado de forma muy notable a la asistencia prestada en las Unidades de Motilidad Digestiva.Superado el pico de mortalidad y contagios por la infección, se ha observado durante las últimas semanas en España y otros países europeos una reducción paulatina en las cifras de transmisión. Sin embargo, el riesgo de reactivación sigue siendo alto, por lo que es necesario disponer de una planificación que permita a los centros sanitarios reiniciar con seguridad para pacientes y profesionales, las exploraciones instrumentales vinculadas al manejo de la patología motora. La Asociación Española de Neurogastroenterología y Motilidad (ASENEM) ha elaborado una serie de recomendaciones prácticas basadas en la evidencia científica disponible y en el consenso de un panel de expertos, y adaptadas a los riesgos inherentes a cada actividad. Se incluyen propuestas de protección individual, pero también medidas organizativas y estructurales, cuyo objetivo es permitir reanudar progresivamente las exploraciones, minimizando la posibilidad de contagio


The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was responsible for the outbreak of the 2019 coronavirus disease (COVID-19), which is now considered as a pandemic. The prevention strategies adopted have included social distancing measures and the modification, reduction or interruption of a large proportion of routine healthcare activity. This has had a significant impact on the care provided in Gastrointestinal Motility Units. Having passed the peak, in terms of mortality and infections, a gradual reduction in transmission figures has been observed in Spain and other European countries. The risk of reactivation, however, remains high, so it is necessary to have a plan in place that allows healthcare centres to safely resume, for their patients and professionals, instrumental examinations linked to the management of motor pathology. Based on the available scientific evidence and the consensus of a panel of experts, the Spanish Association of Neurogastroenterology and Motility (ASENEM) has drawn up a series of practical recommendations, which have been adapted to the risks inherent in each activity. These include individual protection proposals, as well as organisational and structural measures, which are conceived to allow for the gradual resumption of examinations while minimising the possibility of contagion


Assuntos
Humanos , Guias de Prática Clínica como Assunto/normas , Gastroenterologia/normas , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Motilidade Gastrointestinal/fisiologia , Pneumonia Viral/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Espanha/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia
20.
Gen Comp Endocrinol ; 285: 113294, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585115

RESUMO

Motilin and ghrelin were identified in the pheasant by molecular cloning, and the actions of both peptides on the contractility of gastrointestinal (GI) strips were examined in vitro. Molecular cloning indicated that the deduced amino acid sequences of the pheasant motilin and ghrelin were a 22-amino acid peptide, FVPFFTQSDIQKMQEKERIKGQ, and a 26-amino acid peptide, GSSFLSPAYKNIQQQKDTRKPTGRLH, respectively. In in vitro studies using pheasant GI strips, chicken motilin caused contraction of the proventriculus and small intestine, whereas the crop and colon were insensitive. Human motilin, but not erythromycin, caused contraction of small intestine. Chicken motilin-induced contractions in the proventriculus and ileum were not inhibited by a mammalian motilin receptor antagonist, GM109. Neither atropine (a cholinergic receptor antagonist) nor tetrodotoxin (a neuron blocker) inhibited the responses of chicken motilin in the ileum but both drugs decreased the responses to motilin in the proventriculus, suggesting that the contractile mechanisms of motilin in the proventriculus was neurogenic, different from that of the small intestine (myogenic). On the other hand, chicken and quail ghrelin did not cause contraction in any regions of pheasant GI tract. Since interaction of ghrelin and motilin has been reported in the house musk shrew, interaction of two peptides was examined. The chicken motilin-induced contractions were not modified by ghrelin, and ghrelin also did not cause any contraction under the presence of motilin, suggesting the absence of interaction in both peptides. In conclusion, both the motilin system and ghrelin system are present in the pheasant. Regulation of GI motility by motilin might be common in avian species. However, absence of ghrelin actions in any GI regions suggests the avian species-related difference in regulation of GI contractility by ghrelin.


Assuntos
Aves/metabolismo , Trato Gastrointestinal/fisiologia , Grelina/farmacologia , Motilina/farmacologia , Contração Muscular/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Atropina/farmacologia , Sequência de Bases , Galinhas , Clonagem Molecular , Feminino , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/efeitos dos fármacos , Grelina/química , Grelina/genética , Humanos , Masculino , Motilina/química , Motilina/genética , Proventrículo/efeitos dos fármacos , Codorniz , Ratos , Receptores dos Hormônios Gastrointestinais/metabolismo , Receptores de Neuropeptídeos/metabolismo , Tetrodotoxina/farmacologia
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