Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Thesis (M.Sc. (Pyysiology))--Mahidol University, 1983.

Orientador: Elizete Aparecida Lomazi da Costa Pinto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T13:04:46Z (GMT). No. of bitstreams: 1 VerasNeto_MagnoCardoso_M.pdf: 1277080 bytes, checksum: 79819f766291c884cad1299f8efb29ef (MD5) Previous issue date: 2006 / Resumo: A constipação intestinal é um problema freqüente na população pediátrica e sua apresentação clínica expressa grande heterogeneidade. Um grupo de pacientes constipados apresenta constipação refratária ao tratamento habitual e os conceitos fisiopatológicos clássicos pouco contribuíram para os avanços terapêuticos desejáveis a esses pacientes. O reconhecimento de distúrbios da motilidade gastrointestinal pode contribuir para o entendimento da fisiopatologia da constipação intestinal em crianças. Assim, o objetivo deste trabalho foi comparar os valores dos índices de contratilidade da vesícula biliar em crianças com constipação intestinal crônica funcional com aqueles de crianças sadias. Foi realizado estudo observacional, analítico e transversal, sendo selecionados como casos todos os pacientes com diagnóstico de constipação intestinal funcional, na faixa etária de 2 a 16 anos, em acompanhamento no ambulatório de Gastroenterologia Pediátrica do Hospital das Clínicas da UNICAMP no período de janeiro de 2004 a agosto de 2005. Os controles foram selecionados a partir de Unidades Básicas de Saúde de Campinas e região e pareados por sexo e idade. Casos e controles foram incluídos num protocolo de estudo e em seguida, foi realizado exame ultra-sonográfico pelo mesmo observador, mascarado e com registro dos índices de contratilidade. Foi considerado alterado o índice de contratilidade menor que 25%. Foram avaliados 132 casos e o mesmo número de controles. O índice de contratilidade da vesícula biliar apresentou diferença estatisticamente significativa entre os grupos, sendo menor nos pacientes constipados (31,5 ± 16,9 vs. 41,6 ± 12,7; p<0,001). Não houve diferença significativa no índice de contratilidade da vesícula biliar dos pacientes constipados de acordo com a idade de início da constipação, hábito intestinal, presença de escape fecal ou impactação, sintomas digestivos e uso de laxativos. Concluímos que, para o grupo de pacientes estudados, a contratilidade da vesícula biliar mostrou-se menor. Deste modo, a constipação intestinal pode representar um distúrbio mais amplo da motilidade do trato gastrintestinal / Abstract: Intestinal constipation is a frequent condition in pediatric population. Clinical presentation is heterogeneous. A group of children has a refractory outcome despite habitual therapy. Clinical picture in these children may result from physiopathologic mechanisms related to gastrointestinal motility disorders. Gastrointestinal motility investigation in children with functional constipation may add useful information for managing refractory patients. The objective of this study was to evaluate gallbladder motility in constipated children. An observational, cross-sectional study design was conducted. Research period included patients seen from January, 2004 to August, 2005 in a pediatric outclinic of a School Hospital. All patients with functional constipation assisted in the period were included (age range: 2 - 16 years). The control group was selected from Pediatrics Outclinics which usually sent patients to the School Hospital. The control group was matched for sex and age. Patients were interviewed for filling a study protocol. Gallbladder contractility index, calculated from fast and post-prandial area, was calculated in children with refractory functional constipation, using an ultrassonographic method. Data were compared with results obtained in healthy children. Ultrassonography studies were performed by the same physician in a blinded way. One-hundred-thirty-two constipated children and the same number of healthy children were included. Contractility index from constipated children was inferior than index from healthy children (31,5 ± 16,9 vs. 41,6 ± 12,7, p<0,001). There was no significant difference in contractility index from constipated children analyzed for constipation duration, evacuation frequency, and occurrence of soiling or fecal impaction, laxatives use and clinical symptoms. In a group of children with refractory intestinal constipation the gallbladder motility is reduced when compared with healthy children. This phenomenon may light up the understanding about functional constipation in children / Mestrado / Saude da Criança e do Adolescente / Mestre em Saude da Criança e do Adolescente

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24458号 / 理博第4957号 / 新制||理||1708(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 高橋 淑子, 准教授 佐藤 ゆたか, 教授 中務 真人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

There are many gastrointestinal diseases, such as Crohn’s disease, which can be treated effectively with topical, localized medicine delivered to the intestinal wall through the gastrointestinal tract by the use of a targeted drug delivery capsule. The success of such a delivery method is contingent on the properties of the fluid flow near the delivery site; specifically, how well-mixed the medicine will be in the chyme so that it can act on the intestinal wall. Pursuant to understanding the mixed state of the chyme, several fluid simulations were performed with ANSYS Fluent, simulating different types of muscular contractions. Fluid particles – which were originally segregated into three sections of the simulated small intestine – were tracked, and simulation results were compared based on how well-distributed the tracked particles were at the end state, using the second moment of distribution. The results of this comparison have revealed that there is little difference between the mixing produced by segmentation in a 3.0 cm diameter small intestine and that produced in a 2.0 cm diameter small intestine. Results have also shown little difference between mixing produced when the segmentation contractions vary qualitatively in any of several ways. There is, however, some difference between distribution produced by segmentation contractions and peristaltic, or propulsive, contractions. This work could be further pursued with more simulations; of different types of contractions, of contraction patterns with different properties, and with simulations with more comprehensive particle tracking. It would also be straightforward to incorporate analysis of the large intestine into the study. / Mechanical Engineering

Associations between the use of antibiotics and altered brain function and mental illness are now well evidenced from animal models and clinical trials. Based on these findings, emerging research efforts have largely focused on how high-dose antibiotic- mediated perturbations of the gut microbiota result in altered neurophysiological and behavioural outcomes. However, these studies have not investigated whether antibiotics also act directly on the host nervous system. My central hypothesis is that high-dose antibiotics, as used in experimental models testing the modulatory role of the gut microbiome, can induce pathophysiological outcomes by direct interaction with enteric neuronal circuits. I designed two sets of experiments to characterize the acute effect of high-dose antibiotics on gut motility and gut-brain neuronal signalling. The first experimental study aimed to determine whether acute exposure of the gastrointestinal tract to high-dose antibiotics directly modulates enteric neurons, with consequences for gut motility. To test this, I used enteric nervous system dependent motility reflexes, ex vivo, as an index of putative effects on the intestinal nervous system. The results of these experiments have shown that luminal antibiotics alter oral to anal propulsive peristalsis in a system where such motility is dependent on the enteric nervous system. The second study aimed to test whether these local effects modulate brain function and behaviour by altering responses of vagal afferent pathways. I performed single-unit recordings from the mesenteric nerve bundle in ex vivo preparations to test this research question. The results suggest that antibiotics can increase activity of extrinsic vagal afferent neurons largely through cholinergic synapses with myenteric IPANs. The present work offers significant therapeutic implications, although its main relevance is in the interpretation of the experimental use of high-dose antibiotics on animal models and where effects on behaviour and the nervous system are attributed solely to alterations in the microbiome. / Thesis / Master of Science (MSc) / Little is known about the mechanisms by which high-dose antibiotics produce changes in gut-brain signalling to negatively affect brain functions and behaviour. Although the general consensus is that these changes are caused by antibiotic-mediated perturbations of the gut microbiota, whether high-dose antibiotics also act directly on the nervous system remains a topic of debate. I have hypothesized that high-dose antibiotics, as used in experimental models associating pathophysiological outcomes to gut microbial changes, also produce adverse effects by direct modulation of enteric neuronal circuits. Indeed, our findings suggest that high-dose antibiotics directly signal to enteric neurons, which locally regulate gut motility reflexes and can transmit that information further to vagal neurons, to influence homeostatic regulation of brain functions and behaviour. This work offers novel therapeutic potential for antibiotics and advises careful interpretation of studies that have attributed effects of high-dose antibiotics solely to alterations in the gut microbiome.

Gut regulatory peptides, such as neuropeptides and incretins, play important roles in hunger, satiety and gastrointestinal motility, and possibly mucosal permeability. Many peptides secreted by myenteric nerves that regulate motor control are also produced in mucosal epithelial cells. Derangements in motility and mucosal permeability occur in many diseases. Current knowledge is fragmentary regarding gut peptide actions and mechanisms in motility and permeability. This thesis aimed to 1) develop probes and methods for gut permeability testing, 2) elucidate the role of neuropeptide S (NPS) in motility and permeability, 3) characterize nitrergic muscle relaxation and 4) characterize mechanisms of glucagon-like peptide 1 (GLP-1) and the drug ROSE-010 (GLP-1 analog) in motility inhibition. A rapid fluorescent permeability test was developed using riboflavin as a transcellular transport probe and the bisboronic acid 4,4'oBBV coupled to the fluorophore HPTS as a sensor for lactulose, a paracellular permeability probe. This yielded a lactulose:riboflavin ratio test. NPS induced muscle relaxation and increased permeability through NO-dependent mechanisms. Organ bath studies revealed that NPS induced NO-dependent muscle relaxation that was tetrodotoxin (TTX) sensitive. In addition to the epithelium, NPS and its receptor NPSR1 localized at myenteric nerves. Circulating NPS was too low to activate NPSR1, indicating NPS uses local autocrine/paracrine mechanisms. Nitrergic signaling inhibition by nitric oxide synthase inhibitor L-NMMA elicited premature duodenojejunal phase III contractions in migrating motility complex (MMC) in humans. L-NMMA shortened MMC cycle length, suppressed phase I and shifted motility towards phase II. Pre-treatment with atropine extended phase II, while ondansetron had no effect. Intestinal contractions were stimulated by L-NMMA, but not TTX. NOS immunoreactivity was detected in the myenteric plexus but not smooth muscle. Food-intake increased motility of human antrum, duodenum and jejunum. GLP-1 and ROSE-010 relaxed bethanechol-induced contractions in muscle strips. Relaxation was blocked by GLP-1 receptor antagonist exendin(9-39) amide, L-NMMA, adenylate cyclase inhibitor 2´5´-dideoxyadenosine or TTX. GLP-1R and GLP-2R were expressed in myenteric neurons, but not muscle. In conclusion, rapid chemistries for permeability were developed while physiological mechanisms of NPS, nitrergic and GLP-1 and ROSE-010 signaling were revealed. In the case of NPS, a tight synchrony between motility and permeability was found.

A doença do refluxo gastroesofágico (DRGE), apresenta significativa variedade de sintomas e sinais esofagianos ou extra-esofagianas. Entre suas complicações, embora pouco freqüentes, estão o esôfago de Barrett e o adenocarcinoma, sendo, portanto, fundamental reconhecer os fatores implicados na etiologia e agravamento da DRGE. Nos últimos anos, tem sido dada maior importância à influência da atividade física na DRGE. Investigações recentes, embora com resultados conflitantes, em sua maioria, apontam para a exacerbação do refluxo gastroesofágico (RGE) durante o exercício físico. OBJETIVOS: Avaliar a influência da atividade física na DRGE, por meio do teste ergométrico de esforço (TE), em pacientes portadores de doença erosiva, bem como a relevância do tônus do esfíncter inferior do esôfago (EIE) e do índice de massa corporal (IMC), comparando com um grupo de pacientes portadores da forma não erosiva da doença. MÉTODOS: Foram avaliados prospectivamente 29 pacientes portadores de DRGE erosiva e, como grupo controle, 10 pacientes com a doença não erosiva. Todos foram submetidos à avaliação clínica, realização de endoscopia digestiva alta, manometria e pHmetria esofágica. Também realizaram TE precedendo a retirada da sonda de pH-metria. As seguintes variáveis foram avaliadas: eficácia do TE, consumo máximo de oxigênio (VO2max), tempo de refluxo ácido (TRA) e sintomas de RGE durante o TE, influência do tônus do EIE e do IMC na ocorrência de RGE no TE. RESULTADOS: A VO2max demonstrou correlação significativa somente no grupo de pacientes com esofagite erosiva quando esta foi maior ou igual a 70% (p=0,032) durante a realização do TE. As demais variáveis analisadas não demonstraram influência significativa entre a ocorrência de RGE e atividade física (p>0,05). CONCLUSÕES: 1) Atividade física de alta intensidade pode predispor a ocorrência de episódios de refluxo gastroesofágico em portadores de DRGE erosiva; 2) Atividade física de baixa intensidade ou de curta duração não exercem influencia, independentemente do IMC; 3) O tônus do EIE não exerce influência na ocorrência de episódios de RGE durante realização de TE / Gastroesophageal Reflux Disease (GERD) is a worldwide prevalent condition that exhibits a large variety of signs and symptoms of esophageal or extraesophageal nature and can be related to the adenocarcinoma of the esophagus. Therefore, its of crucial importance to recognize the etiologic and aggravating factors of GERD. In the last few years, greater importance has been given to the influence of physical exercises on GERD. Some recent investigations, though showing conflicting results, point to an exacerbation of gastroesophageal reflux during physical exercises. Objectives: To evaluate the influence that physical activities can have on GERD patients presenting with erosive and non erosive disease by means of an ergometric stress test and evaluate the influence of the lower esophageal sphincter tonus and body mass index (BMI) during this situation. METHODS: Twenty-nine GERD patients with erosive disease (group I) and 10 patients with non-erosive disease (group II) were prospectively evaluated. All the subjects were submitted to clinical evaluation, followed by upper digestive endoscopy, manometry and 24h esophageal pH monitoring. A stress test was performed 1 hour before removing the esophageal pH probe. During the ergometric stress test, the following variables were analyzed: test efficacy, maximum oxygen uptake (VO2 max), duration of acid reflux and gastroesophaeal reflux symptoms and the influence of the lower esophageal sphincter tonus and influence of body mass index (BMI) in the occurrence of GER during these physical stress. RESULTS: VO2 max showed significant correlation when it was 70% or higher only in the group of erosive disease, evaluating the patients with or without acid reflux during the stress test (p = 0,032). The other variables considered didnt show significant correlations between gastroesophageal reflux and physical activity (p > 0,05). CONCLUSIONS: 1) Highly intensive physical activity can predispose the occurrence of gastroesophageal reflux episodes in GERD patients with erosive disease. 2) Light or short sessions of physical activity have no influence on reflux, regardless of BMI. 3) The tonus of the lower esophageal sphincter does not influence the occurrence of episodes of GER during exercise testing

In an irritable bowel syndrome (IBS) rat model, S. chinensis reversed the exaggerated visceral nocicptive responses (judged by abdominal withdrawal reflex and electromyographic measurement) to colorectal distension induced by neonatal maternal separation. Relief of visceral hypersensitivity by S. chinensis could be related to the decrease of elevated 5-HT level and the reduction in 5-HT3 receptor expression in colon. / In summary, given the modulatory effects on intestinal motility and visceral sensation, Schisandra chinensis would be potentially useful for the treatment of relieving diarrhea and visceral pain symptoms in IBS patients. Schisandra lignans, the major absorbable components, can be regarded as the active ingredients in S. chinensis for the potential treatment of IBS. / Schisandra chinensis, which is named "Wu-Wei-Zi" in Chinese Pin Yin, is widely used in Chinese medicine as an astringent, tonic and sedative agent. Dibenzo[a,c]-cyclooctadiene lignans are the major components of this herb. In the present study, the chemical constituents of S. chinensis were first characterized. A HPLC-DAD method was developed and validated for quantitative analysis of four major Schisandra lignans, namely, schisandrin (SCH-1), gomisin A (SCH-2), deoxyschisandrin (SCH-3) and gamma-schisandrin (SCH-4), in the aqueous and ethanolic extracts of S. chinensis. The ethanolic extract contains higher amount of lignan components than aqueous extract. The HPLC method has also been employed to obtain chromatographic fingerprintings to distinguish S. chinensis from a related species, S. sphenanthera. / The modulatory effects of both S. chinensis extracts and four major lignans on intestinal motility were evaluated using in vitro intestinal motility assays. The tested compounds induced relaxation on guinea pig ileum contracted by acetylcholine, serotonin and electrical field stimulation, as well as on rat colon with spontaneous contractility. While SCH-3 was most potent in inhibiting sensorimotor response in guinea pig ileum, SCH-1 displayed the highest potency of inhibition on spontaneous contraction of rat colon. / The relaxant effect on rat colon induced by SCH-1 has been demonstrated to involve two or more non-adrenergic non-cholinergic mediators. Nitric oxide was likely to be one of the inhibitory transmitters that involved cGMP-dependent pathways, whereas the non-nitrergic component was apamin-sensitive, but probably excluded vasoactive intestinal peptide (VIP) and adenosine. / With the aid of HPLC-DAD-MS for qualitative and quantitative analyses, the absorption of S. chinensis in the rat everted gut sac and human Caco-2 monolayer in vitro models have been profiled. Fifteen Schisandra lignans were identified as the major absorbable components of S. chinensis in these models. Transport study on SCH-1 has shown a passive diffusion pathway with high permeability. In an in vivo study, metabolites of Schisandra lignans could be found in rat plasma after a single oral administration of S. chinensis extract. The plasma pharmacokinetics of S. chinensis in rats was further evaluated using simultaneous quantification of four representative Schisandra lignans (SCH-1, SCH-2, SCH-3 and SCH-4). / Yang, Jiaming. / Adviser: Chun-Tao Che. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 262-283). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Dysfunktion av den gastrointestinala motiliteten under det postoperativa skedet är en komplikation som kan orsakas till följd av kirurgiska ingrepp. Detta kan orsaka bukspänning, illamående samt smärta som komplicerar en ofullständig och snabb återhämtning efter kirurgiska ingrepp. Dysfunktion av den gastrointestinala motiliteten ökar risken för ytterligare postoperativa komplikationer som uttorkning, elektrolytrubbning och sepsis. Samt ökar riskerna för reoperation och återintagning på sjukhus efter utskrivning. Dysfunktion av den gastrointestinala motiliteten kan ge ökat lidande för patienter, skapa längre vårdtider, medföra högre sjukhuskostnader samt öka arbetsbelastningen för hälso- och sjukvårdspersonal. Syfte: Syftet var att beskriva sjuksköterskors omvårdnadsåtgärder vid dysfunktion av den gastrointestinala motiliteten hos patienter under det postoperativa skedet. Metod: Studien genomfördes som en allmän litteraturstudie med induktiv ansats. Resultat: Resultatet baserades på nio vetenskapliga artiklar med kvantitativa ansats. Utifrån kodning av meningsenheter från de vetenskapliga artiklarna framkom fyra huvudkategorier: Patientnära samtal, Mobilisering, Kost- och vätskeintag och Stimulering av den gastrointestinala motiliteten. Slutsats: Omvårdnadsåtgärder var en viktig del i förebyggandet för främjandet av den gastrointestinala motiliteten under det postoperativa skedet samt förbättrade möjligheten till ett tidigare tillfrisknande för patienter. Ett tidigt ingripande med omvårdnadsåtgärder till patienter som genomgått kirurgi bidrog det till minskat lidande, kortare vårdtider för patienterna samt minskad arbetsbelastning för hälso- och sjukvårdspersonal. / Dysfunction of the gastrointestinal motility in the post-operative stage is a complication that can be caused by surgical procedures. This can cause abdominal tension, nausea and pain that complicate an incomplete and rapid recovery after surgery. Dysfunction of gastrointestinal motility increases the risk of additional postoperative complications such as dehydration, electrolyte disruption and sepsis. As well as increasing the risk of reoperation and readmission in hospitals after discharge. Dysfunction of the gastrointestinal motility can lead to increased suffering for patients, create longer care times, bring higher hospital costs and increase the workload of healthcare professionals. Purpose: The purpose was to describe nursing care measures in dysfunction of the gastrointestinal motility to patients in the postoperative stage. Method: The study was conducted as a literature review with inductive approach. Result: The result was based on nine scientific articles with quantitative approaches. Based on the coding of opinion units from the scientific articles, four main categories emerged: Patient-related conversation, Mobilization, Diet and fluid intake and Stimulation of gastrointestinal motility. Conclusion: Nursing care measures were an important part of the prevention of the promotion of gastrointestinal motility in the postoperative stage, and improved the possibility of an earlier recovery for patients. Early intervention with nursing care measures for patients who have undergone surgery, it contributed to reduced suffering, shorter patient care times and reduced workload for healthcare professionals.