Dissertations / Theses on the topic 'Gastrointestinal system'
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1
Bennett, Ethelle. "Functional gastrointestinal disorders relations between psychosocial factors, symptoms and sensorimotor disturbance /." Connect to full text, 1999. http://hdl.handle.net/2123/410.
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Thesis (Ph. D.)-- University of Sydney, 1999.Title from title screen (viewed Apr. 21, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Depts. of Psychological Medicine and Medicine. Includes tables. Includes bibliography. Also available in print form.
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Ababio, Frank James Kweku. "The endocannabinoid system in inflammatory bowel system." Thesis, Nelson Mandela Metropolitan University, 2014. http://hdl.handle.net/10948/d1020338.
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Crohn’s disease (CD) and ulcerative colitis (UC) constitute the two major forms of inflammatory bowel disease (IBD), which are disorders of chronic inflammation in the gastrointestinal tract that are associated with significant morbidity and socioeconomic burden. IBD patients with long-standing intestinal inflammation are more prone to developing colorectal cancer (CRC). Until now, none of the existing IBD treatments is able to heal the mucosal ulcerations satisfactorily. The endocannabinoid system (ECS), which comprises of endogenous cannabinoid ligands, their receptors, and metabolic enzymes, has been implicated in gut homeostasis, visceral sensation, inflammation and gastrointestinal motility. Available studies in rodent models of IBD suggest that enhancing the ECS tone may reduce inflammation and improve mucosal integrity. This evidence indicates that the components of the ECS seem well positioned to exert a protective role in IBD and also to offer a great opportunity for therapeutic exploitation. Despite the role of the ECS in the gut, the presence and function of the components of the ECS is not well characterised in human IBD. The primary aim of the study was to investigate the state of the major components of the ECS in human IBD and to establish whether IBD is associated with any changes of the components of the ECS. Cannabinoid CB1 and CB2 receptors, enzymes for endocannabinoid biosynthesis PLC, “LRAT”, NAPE-PLD and DAGL, and endocannabinoid metabolic enzymes FAAH and MAGL were analysed from colonic tissue samples of CD, UC and control patients by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) to determine the relative mRNA expression of the above genes. The RT-qPCR analysis showed that the mRNA expression of PLC, LRAT, and NAPE-PLD were unchanged in both CD and UC, whiles DAGL mRNA was decreased in UC but was unchanged in CD. The endocannabinoid degradation enzymes, FAAH mRNA expression was also unchanged in CD but decreased in UC, whereas the mRNA expression of MAGL was significantly decreased in both CD and UC. NAPE-PLD/FAAH and DAGL/MAGL ratios, an estimation of the balance of AEA and 2-AG levels, showed that AEA and 2-AG levels could be increased and unchanged, respectively, in IBD. The mRNA expression of CB1 was significantly decreased in CD and UC whilst CB2 mRNA expression was unchanged in both forms of IBD. The study demonstrated that the components of the ECS which were investigated were present in colonic tissues of both IBD patients and healthy individuals, but they appear to be off balance in CD and UC patients. The decreased CB1 receptors in IBD patients could be an important modifier in the disease and could also provide a possible pathoaetiological mechanism linking IBD and CRC. Although these findings look promising, more studies with larger sample size are required to characterise the components of the ECS in human IBD.
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Andrews, Jane Mary. "Relationships between motor and sensory function in the proximal gut, appetite, & nutrients in healthy human subjects." Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09pha567.pdf.
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Bibliography: leaves 206-251. The motor and sensory interactions between nutrients and proximal gut in humans are not well understood, despite the pivotal importance of these interactions on appetite, absorption and thus, nutrition. In part, this lack of knowledge results from technical difficulties in studying motor function in the human gut. In particular, the inability to continuously measure intraluminal flow with any degree of temporal resolution, has impeded progress in this field. The studies described in this thesis focus on nutrient-gut interactions, and also on the development of novel methodologies aimed at advancing the understanding and interpretation of the relationships between intraluminal pressures and flows.
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Stevenson, Diane J. "P2X7, inflammation and gastrointestinal disease." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/28897/.
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The inflammatory bowel diseases, ulcerative colitis and Crohn's disease are characterised by spontaneously relapsing and remitting inflammation, associated with increased mucosal levels of the inflammatory cytokine, interleukin-1 (IL-1)β. IL-1β processing and release is mediated by ATP stimulation of the purine receptor, P2X7. P2X7 is a membrane ion channel highly expressed in immune cells. Signal transduction occurs via rapid cation exchange, plasma membrane depolarisation and increased intracellular calcium. Additionally, prolonged or repeated P2X7 stimulation leads to formation of a non-selective membrane pore permeable to small molecules, and ultimately to cell death. The aim of this project was to investigate the properties of the P2X7 receptor in mononuclear cells, to show that it is associated with IL-1β release in the colon, and that this release can be modified by P2X7 antagonists. Studies of ethidium bromide uptake, a functional assay, showed that P2X7 receptors are present on LPMCs and displayed properties similar to those of PBMCs and THP-1 cells. P2X7 receptor-stimulation released mature IL-1β from LPMCs in a dose-dependent manner that, in IBD patients, matched the severity of their inflammation, and could be markedly reduced by P2X7 antagonists. P2X7 stimulation also results in increased exposure of phosphatidylserine on the outer cell membrane (PS flip), often considered to be a marker of apoptotic cell death. P2X7-stimulated PS flip however is reversible and is not associated with cell death following brief stimulation times. Cell death caused by longer stimulation did not have features of apoptosis, was more evident in monocytes than lymphocytes, with LPMCs being less susceptible than PBMCs and THP-1 cells. These studies have shown that the P2X7 receptor is intimately involved in the release of IL-1β from human colonic mononuclear cells, that the release is greater in cells from IBD tissue and can be markedly inhibited by P2X7 antagonists.
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Njuguna, Peter. "Studies on the manipulation of gastrointestinal tract bacteria." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060719.125402/index.html.
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Brauns, Seth Clint Aron. "Physiological and non-physiological induction of gastrointestinal differentiation." Thesis, University of Port Elizabeth, 1999. http://hdl.handle.net/10948/d1015521.
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The human colonic carcinoma cell lines HT-29 and Caco-2 both exhibit structural and functional differentiation under appropriate culture conditions. HT-29 can be induced to differentiate by treatment with short-chain fatty acids or acetoacetate. Caco-2 cells differentiate spontaneously upon contact inhibition. In this study HT-29 cells were treated with 5 mM acetate, propionate, butyrate and acetoacetate (physiological inducers) to assess their effects on the expression of carbonic anhydrase 1, sucrase-isomaltase and alkaline phosphatase which are reported to be markers of gastrointestinal differentiation. The maturation induction observed was compared to that of the spontaneous differentiation observed in Caco-2 cells. Assays were performed over an 18 day period. Results showed a close correlation (p < 0.05) between HT-29 and Caco-2 cell on days 4 and 12. These results indicate that differentiation reported in both cell lines is comparable and can be used as a basis for further comparative studies. In addition, parallel experiments to the above were conducted using a selection of nine rationally designed cyclic dipeptides (CDPs) potential drug entities which were chosen as non-physiological inducers. The results showed that the cyclic dipeptides were able to induce the gastrointestinal phenotype as observed in HT-29 cells treated with physiological inducers. Studies on the effects of energy-related metabolism in HT-29 and Caco-2 cells as induced by physiological and non-physiological inducers indicated that energy metabolism is a significant role player in gastrointestinal differentiation. The results reported show a decrease in ATP concentrations indicating that the cyclic dipeptides, like physiological inducers, affect the energy state of the HT-29 cells and thus may effect the differentiation of these cells. A positive correlation was found between histone phsophorylation and differentiation confirming that histone phsophorylation was partly responsible for the decrease in ATP concentrations. It is suggested that the induction of differentiation in HT- 29 cells could be either due to non-specific transcription of genes by activation of a chromatin switch or specific by the activation of signal transduction pathways based on the flux of ATP through the cells. Differential display RT-PCR is probably the most sensitive method that could be used to validate the suggestion of either a nonspecific transcription of genes or a specific differentiation reported for HT-29 cells.
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Karling, Pontus. "The emotional motor system and gastrointestinal symptoms." Doctoral thesis, Umeå universitet, Folkhälsa och klinisk medicin, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1802.
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There is a significant comorbidity between anxiety/depression and functional gastrointestinal syndromes, such as irritable bowel syndrome (IBS) and functional dyspepsia. The pathophysiological link between emotions and the gut is not known. A model of an emotional motor system (EMS) which reacts to interoceptive and exteroceptive stress has been proposed. EMS consists of specific brain structures including anterior cingulate cortex (ACC), amygdala, hippocampus and hypothalamus and mediates their communication to the rest of the body (including the gastrointestinal tract) through the hypothalamus-pituitary-adrenal (HPA) axis, the autonomic nervous system (ANS) and by a pain modulation system. The aim of this thesis was to test the EMS model by studying the relationship between symptoms of anxiety and depression and IBS-like symptoms in patients with recurrent unipolar depression, in patients with IBS and in a sample of a normal Swedish population. The peripheral limb of EMS (ANS, HPA axis and the pain modulations system) was tested in patients with IBS and control subjects. Spectral heart rate variability was used to investigate ANS function in patients with refractory IBS and in healthy controls. The HPA axis function was tested by a weight adjusted low dose dexamethasone suppression test in control subjects. The influence of catecholamine degradation on pain modulation was tested by analyzing val158met catechol-o-methyl transferase (COMT) polymorphism in patients with IBS and in control subjects. We found a significant relationship between symptoms of anxiety/depression and IBS-like symptoms in patients with recurrent unipolar depression, in patients with IBS and in a sample of the normal population. Interestingly, patients with recurrent unipolar depression in remission had no more IBS-like symptoms than controls, indicating that the gastrointestinal symptoms may resolve when depression is treated to remission. Patients with IBS have an increased mid-frequency power in rest and in supine position (after tilt test) compared to healthy controls indicating an increased sympathetic ANS drive. The symptoms of diarrhea and early satiety has in the litterature been associated to the stimulation of corticotropin releasing hormone (CRH) receptors and was also in our study related to HPA axis function tested by a low dose dexamethasone test. Interestingly both hypo- and hyperfunction of the HPA axis was related to these symptoms in control subjects. The val158met COMT polymorphism was associated to IBS-like symptoms. Control subjects with IBS-like symptoms (defined by the upper quartile in total GSRS-IBS score) had a higher frequency of the met/met and a significantly lower frequency of the val/met genotype. Also patients with IBS tended to have a lower frequency of the heterozygous val/met genotype so we conclude that this genotype may be protective against IBS/IBS like symptoms. In addition, the val/val genotype in patients with IBS was associated to diarrhea symptoms. Conclusions: Our results support the model of an emotional motor system in the genesis of functional gastrointestinal symptoms by the finding of the association of IBS-like symptoms and mood disturbances, and by finding alterations in the peripheral limbs of EMS (ANS, HPA axis and catecholamines) in subjects with IBS and IBS-like symptoms.
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Crooks, Colin J. "The epidemiology of upper gastrointestinal bleeding." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13394/.
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Background There have been many conflicting changes in the prevalence of the risk factors for upper gastrointestinal bleeding and therefore it is not clear what the current trends in mortality or incidence are, nor which factors are important in driving these trends. As populations in many countries are ageing with an increasing burden of co-morbidity, this thesis investigates whether the relationship between non gastrointestinal co-morbidity and upper gastrointestinal bleeding might be an explanation for current trends. I hypothesised that non gastrointestinal co-morbidity was responsible for a large proportion of bleeds in the population and the deaths that occur following a bleed. Methodology Large scale routine population based data records were used to assess the current incidence and mortality trends of upper gastrointestinal bleeding in England, as well as more in depth studies of predictors of its occurrence and subsequent mortality. The databases were examined and compared to external sources to assess their representativeness, and methods for defining cases in linked primary and secondary care were developed. The specific questions addressed in the studies were: 1. What are the current trends and variations in occurrence of upper gastrointestinal bleeding? Incidence rates and adjusted incidence rate ratios were calculated by quintiles of socioeconomic status, age group, sex, region, and calendar year. 2. Has there been an improvement in 30 day mortality following upper gastrointestinal bleeding? A nested case control study using Hospital Episodes Statistics from England 1999-2007 examined mortality trends by age, sex, co-morbidity and type of bleed. 3. Does non gastrointestinal co-morbidity predict upper gastrointestinal bleeding? A matched nested case control study used the linked Hospital Episodes Statistics and General Practice Research Database to examine non gastrointestinal co-morbidity as a risk factor adjusted for other known risk factors for bleeding. Sequential population attributable fractions were calculated to estimate what each risk factor contributed to the disease burden. 4. What are the excess causes of death following upper gastrointestinal bleeding? Causes of death by ICD 10 category were extracted following a bleed from the linked Office for National Statistics death register. Crude mortality rates and excess cumulative incidence functions were calculated; the latter adjusted for the competing risks between different causes of death. Results 1. A higher incidence of upper gastrointestinal bleeding was observed in the north of England, but this variation was dwarfed by the variation associated with deprivation. Areas of greater deprivation had 2-3 fold higher rates of hospitalisation for upper gastrointestinal bleeding than areas of less deprivation suggesting that strong modifiable risk factors exist. 2. Over the last decade there was a 20% improvement in 28 day mortality following upper gastrointestinal bleeding, and those admitted with bleeding were increasingly older and had more co-morbidity. 3. A combined measure of non gastrointestinal co-morbidity was a significant independent predictor of upper gastrointestinal bleeding and explained a greater proportion of the burden of bleeding (19%) than any other risk factor in the population, including medications such as aspirin and NSAIDs. 4. More than half the absolute excess risk of death was due to co-morbidity not related to the upper gastrointestinal tract. Conclusions Non gastrointestinal co-morbidity both strongly predicts an event of upper gastrointestinal bleeding, and is responsible for a large proportion of the subsequent long term mortality. The magnitude of the association in the population explains both why its incidence had not decreased, and why the improvements in mortality were observed irrespective of endoscopic management or bleed type. Furthermore a bleed can be an indicator for a re-assessment of the severity of co-existing non gastrointestinal morbidity.
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Flachsenberger, Wolfgang Arthur. "Studies on the peristaltic reflex /." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phf571.pdf.
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Yip, Bon-ham. "Immunoglobulin gene translocations in gastric lymphoma." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37345321.
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Royal, E. L. "Interplay between hypoxia and gastrin in gastrointestinal cancer." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10805/.
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Tumour hypoxia has been linked to increased resistance to both radiotherapy and chemotherapy, especially in solid metastatic GI tumours. Under hypoxic conditions, genes that promote tumour growth and survival are up-regulated, via the transcription factor hypoxia-inducible factor-1 (HIF-1). The digestive hormone gastrin, which is often over-expressed in GI cancers, has also been shown to act as a pro-survival factor, up-regulating processes such as tumour proliferation, angiogenesis and migration, and down-regulating apoptosis. Due to the high level of similarity between the downstream events mediated by the two proteins, the relationship between gastrin and HIF-1 was investigated. HIF-1α nuclear protein expression was inducible under hypoxic conditions, which led to an expected increase in VEGF gene expression, followed by a 12-50 fold increase in hypoxic gastrin mRNA expression. HIF-1α expression and transcriptional activity were not consistently affected by exogenous gastrin. RNA-interference-mediated knockdown of HIF-1α resulted in a 40-60% down-regulation of gastrin gene expression under hypoxic conditions suggesting that HIF-1α is partially responsible for gastrin up-regulation in hypoxia. Potential hypoxia-response elements (HREs) were identified within the gastrin promoter, but were only partially responsive to hypoxic incubation in GI carcinoma cells in luciferase-reporter assays. Other possible mechanisms that may account for the increased gastrin gene expression induced under hypoxic conditions include interactions of gastrin with other transcriptional regulators, either in synergy with or independent from HIF-1, or the sequestration of gastrin within the cell by ‘P’-bodies or RNA-binding proteins. These findings may indicate that the addition of anti-gastrin agents such as CCK-2 receptor antagonists or gastrin immunogens to the treatment regime of patients with solid GI tumours may be clinically beneficial, especially if combined with agents used to reduce radiotherapy and chemotherapy resistance.
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Wixner, Jonas. "Gastrointestinal disturbances in hereditary transthyretin amyloidosis." Doctoral thesis, Umeå universitet, Institutionen för folkhälsa och klinisk medicin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-88745.
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Background Transthyretin amyloid (ATTR) amyloidosis is a systemic disorder caused by amyloid deposits formed by misfolded transthyretin (TTR) monomers. Two main forms exist – wild-type and hereditary ATTR amyloidosis, the latter associated with TTR gene mutations. Wild-type ATTR amyloidosis has a late onset and primarily cardiac manifestations, whereas hereditary ATTR amyloidosis is a rare autosomal dominant condition with a considerable phenotypic diversity. Both disorders are present all over the world, but endemic areas of the hereditary form are found in Sweden, Portugal, Brazil and Japan. Gastrointestinal (GI) complications are common in hereditary ATTR amyloidosis and play an important role in the patients’ morbidity and mortality. Malfunction of the autonomic and enteric nervous systems has been proposed to contribute to the GI disturbances, but the underlying mechanisms have not been fully elucidated. The aims of this thesis were to assess the prevalence of GI disturbances for different subtypes of ATTR amyloidosis, to further explore the mechanisms behind these disturbances, and to evaluate the outcome of the patients’ GI function after liver transplantation, which currently is the standard treatment for hereditary ATTR amyloidosis. Methods The Transthyretin Amyloidosis Outcomes Survey (THAOS) is the first global, multicenter, longitudinal, observational survey that collects data on patients with ATTR amyloidosis. THAOS enrollment data were used to assess the prevalence of GI symptoms and to evaluate their impact on nutritional status (mBMI) and health-related quality of life (EQ-5D Index Score). Data from routine investigations of heart-rate variability and cardio-vascular response to tilt tests were utilized to evaluate the impact of autonomic neuropathy on the scintigraphically measured gastric emptying half-times in Swedish patients with hereditary ATTR amyloidosis. Gastric wall autopsy specimens from Japanese patients with hereditary ATTR amyloidosis and Japanese non-amyloidosis controls were analyzed with immunohistochemistry and computerized image analysis to assess the densities of interstitial cells of Cajal (ICC) and nervous tissue. Data from gastric emptying scintigraphies and validated questionnaires were used to evaluate the outcome of Swedish patients’ GI function after liver transplantation for hereditary ATTR amyloidosis. Results Sixty-three percent of the patients with TTR mutations and 15 % of those with wild-type ATTR amyloidosis reported GI symptoms at enrollment into THAOS. Subsequent analyses focused on patients with TTR mutations and, among them, unintentional weight loss was the most frequent symptom (32 %) followed by early satiety (26 %). Early-onset patients (<50 years of age) reported GI symptoms more frequently than late-onset cases (70 % vs. 50 %, p <0.01), and GI symptoms were more common in patients with the V30M mutation than in those with non-V30M mutations (69 % vs. 56 %, p <0.01). Both upper and lower GI symptoms were significant negative predictors of nutritional status and health-related quality of life (p <0.01 for both). Weak but significant correlations were found between gastric emptying half-times and the function of both the sympathetic (rs = -0.4, p <0.01) and parasympathetic (rs = -0.3, p <0.01) nervous systems. The densities of c-Kit-immunoreactive ICC were significantly lower in the circular (median density 0.0 vs. 2.6, p <0.01) and longitudinal (median density 0.0 vs. 1.8, p <0.01) muscle layers of the gastric wall in patients compared to controls. Yet, no significant differences in protein gene product 9.5-immunoreactive nervous cells were found between patients and controls either in the circular (median density 3.0 vs. 6.8, p = 0.17) or longitudinal (median density 1.4 vs. 2.5, p = 0.10) muscle layers. Lastly, the patients’ GI symptoms scores had increased slightly from before liver transplantation to the follow-ups performed in median two and nine years after transplantation (median score 7 vs. 10 vs. 13, p <0.01). However, their gastric emptying half-times (median half-time 137 vs. 132 vs. 125 min, p = 0.52) and nutritional statuses (median mBMI 975 vs. 991 vs. 973, p = 0.75) were maintained at follow-ups in median two and five years after transplantation. Conclusion GI disturbances are common in hereditary ATTR amyloidosis and have a negative impact on the patients’ nutritional status and health-related quality of life. Fortunately, a liver transplantation appears to halt the progressive GI involvement of the disease, although the patients’ GI symptoms tend to increase after transplantation. An autonomic neuropathy and a depletion of gastrointestinal ICC seem to contribute to the GI disturbances, but additional factors must be involved.
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Jones, Karen Louise. "Studies of normal and disordered gastric motility in humans /." Title page, table of contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phj777.pdf.
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陳正錕 and Zhengkun Chen. "The patterns and correlates of bowel habits in Hong Kong adolescents." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41709603.
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Chung, Wing Sun Faith. "Development of new targeted prebiotic approaches for optimising the human intestinal microbiota." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231536.
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Chen, Zhengkun. "The patterns and correlates of bowel habits in Hong Kong adolescents." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41709603.
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PETERS, STEPHEN. "NONCHOLINERGIC NEUROTRANSMISSION IN THE GUINEA PIG INFERIOR MESENTERIC GANGLION: A SENSORY ROLE IN GASTROINTESTINAL PHYSIOLOGY (SYMPATHETIC, SLOW EPSP, PREVERTEBRAL, VASOPRESSIN, SUBSTANCE P)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188009.
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Noncholinergic neurotransmission was studied in vitro in the guinea pig inferior mesenteric ganglion (IMG) using the technique of intracellular recording. First, the role of substance P (SP) in noncholinergic transmission was examined. Forty-four percent of IMG neurons depolarized upon superfusion of SP (1-10 x 10⁻⁷M); however, some neurons that were insensitive to SP still exhibited slow excitatory potentials (EPSPs) in response to nerve stimulation. During exposure to SP, slow EPSPs were depressed by 52% compared to paired control EPSPs. In animals treated with systemic doses of capsaicin (50-350 mg/kg), mean slow EPSP amplitude was 3.5 mV compared to 6.8 mV in untreated animals. Arginine-vasopressin (AVP) was tested for its electrophysiological effects on IMG neurons and synaptic transmission. AVP (0.5-10 x 10⁻⁷M) produced a depolarization in 67% of neurons, accompanied by an increase in membrane resistance of 44%. The depolarizations and increase in resistance were blocked by a specific V₁ receptor antagonist. During AVP-induced depolarizations, slow EPSPs were reversibly depressed in the majority of neurons by a mean of 71% relative to paired control EPSPs. The V₁ antagonist blocked slow EPSPs in only 10% of neurons tested. A group of neurons exhibiting slow EPSPs was exposed separately to both AVP and SP. Some neurons were exclusively sensitive to either SP or AVP, others were sensitive to both peptides, and still others were sensitive to neither peptide. The physiologic role of noncholinergic transmission was examined using a preparation consisting of a segment of distal colon attached to the IMG. Distension of the colon segment produced a slow depolarization resistant to cholinergic antagonists in 44% of IMG neurons. Distension-induced noncholinergic depolarizations increased in amplitude with colonic intraluminal pressure and with membrane hyperpolarization, and were accompanied by an increase in membrane input resistance of 21%. Capsaicin in vivo reduced the number of neurons exhibiting the noncholinergic mechanosensory depolarization, and in vitro capsaicin and SP desensitization reduced the amplitude of the depolarization. These results suggest that (1) both SP and AVP may be transmitters of noncholinergic potentials in the IMG, (2) some IMG neurons receive heterogeneous peptidergic innervation, and (3) noncholinergic transmission in the IMG is involved in sensory regulation of visceral autonomic function.
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Thomas, Evan Alexander. "Mathematical and computer modelling of the enteric nervous system." Connect to thesis, 2001. http://repository.unimelb.edu.au/10187/2872.
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The enteric nervous system (ENS) runs within the intestinal wall and is responsible for initiating and enacting several reflexes and motor patterns, including peristalsis and the complex interdigestive motor programs, known as migrating motor complexes (MMCs). The ENS consists of several neuron types including intrinsic sensory neurons, interneurons and motor neurons. A great deal is known about the anatomy, pharmacology and electrophysiology of the ENS, yet there is almost no understanding of how enteric neural circuits perform the functions that they do and how they switch from one function to another. The ENS contains intrinsic sensory neurons (ISNs) that connect to every neuron type in the ENS, including making recurrent connections amongst themselves. Thus, they are likely to play a key role, not just in sensory transduction, but in coordination of reflexes and motor patterns. This thesis has explored how these functions are performed by developing and analysing mathematical and computer models of the network of ISNs. (For complete abstract open document)
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Sinagoga, Katie Lynn. "Development and Maturation of Endocrine Cells of the Gastrointestinal System." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1529667099100792.
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Malloy, Jaclyn. "CENTRAL AND PERIPHERAL REGULATION OF CIRCADIAN GASTROINTESTINAL RHYTHMS." UKnowledge, 2012. http://uknowledge.uky.edu/biology_etds/5.
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Circadian clocks are responsible for daily rhythms in gastrointestinal function which are vital for normal digestive rhythms and health. The present study examines the roles of the circadian pacemaker, the suprachiasmatic nuclei (SCN), and the sympathetic nervous system in regulation of circadian gastrointestinal rhythms in Mus musculus. Surgical ablation of the SCN abolishes circadian locomotor, feeding, and stool output rhythms when animals are presented with food ad libitum, while restricted feeding reestablishes these rhythms temporarily. In intact mice, chemical sympathectomy with 6- hydroxydopamine has no effect on feeding and locomotor rhythmicity, but attenuates stool output rhythms. Again, restricted feeding reestablishes these rhythms. Ex vivo, intestinal tissue from mPer2LUC knockin mice expresses circadian rhythms of luciferase bioluminescence. 6-hydroxydopamine has little effect upon these rhythms, but timed administration of β−adrenergic agonist isoproterenol causes a phase-dependent phase shift in PERIOD2 expression rhythms. Collectively, the data suggest the SCN are required to maintain feeding, locomotor and stool output rhythms during ad libitum conditions, acting at least in part through daily activation of sympathetic activity. Even so, this input is not necessary for entrainment to timed feeding, which may be the province of oscillators within the intestines themselves or other components of the gastrointestinal system.
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Spear, Estelle Trego. "Altered Gastrointestinal Motility in Multiple Sclerosis." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/837.
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Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that causes motor, visual, and sensory symptoms. Patients also experience constipation, which is not yet understood, but could involve dysfunction of the enteric nervous system (ENS). Autoimmune targeting of the ENS occurs in other autoimmune diseases that exhibit gastrointestinal (GI) symptoms, and similar mechanisms could lead to GI dysfunction in MS. Here, we characterize GI dysmotility in the experimental autoimmune encephalomyelitis (EAE) model of MS and test whether autoantibodies targeting the ENS are present in the serum of MS patients.
Male SJL or B6 mice were induced with EAE by immunization against PLP139-151, MOG35-55, or mouse spinal cord homogenate, and monitored daily for somatic motor symptoms. EAE mice developed GI symptoms consistent with those observed in MS. In vivo motility analysis demonstrated slower whole GI transit, and decreased colonic propulsive motility. EAE mice had faster rates of gastric emptying, with no changes in small intestinal motility. Consistent with these results, ex vivo evaluation of isolated colons demonstrated that EAE mice have slower colonic migrating myoelectric complexes and slow wave contractions. Immunohistochemistry of EAE colons exhibited a significant reduction in GFAP area of ENS ganglia, with no changes in HuD, S100, or neuron numbers.
To test whether antibodies in MS bind to ENS structures, we collected serum samples from MS patients with constipation and without constipation, and healthy control patients without constipation. Immunoreactivity was tested using indirect immunofluorescence by applying serum samples to guinea pig ENS tissue. MS serum exhibited significantly higher immunoreactivity against guinea pig ENS than control patients, which was particularly evident in MS patients who did not experience constipation. There was no significant difference in immunoreactivity between MS patients with and without constipation. Targets of human MS and mouse EAE serum include enteric glia and neurons.
Taken together, these data validate EAE as a model for constipation in MS, and support the concept that this symptom involves changes within the neuromuscular system of the colon. EAE mice develop symptoms consistent with constipation that affects functional ENS networks and may result in structural or phenotypic changes at the cellular level. Serum immunoreactivity suggests that autoantibodies could play a role in the development of constipation in MS by targeting the ENS itself.
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Cheng, Wai-chun. "Studying Hoxb5 functions in enteric nervous system development by dominant-negative repressor engrailed-Hoxb5." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39634528.
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Cheng, Wai-chun, and 鄭維俊. "Studying Hoxb5 functions in enteric nervous system development by dominant-negative repressor engrailed-Hoxb5." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39634528.
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Thornton, David James. "Determination of aluminum concentration in serum and tissue : factors affecting the gastrointestinal absorption of aluminum /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487265555438291.
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Gutierrez, Orozco Fabiola. "Influence of tea catechins on the viability, IL-8 synthesis and secretion, and NF-[kappa]B activation of gastric epithelial AGS cancer cells." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1230670032.
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Edlund, Charlotta. "Ecological aspects of new quinolones impact on human oropharyngeal and gastrointestinal microflora /." Stockholm : Kongl. Carolinska Medico Chirurgiska Institutet, 1989. http://catalog.hathitrust.org/api/volumes/oclc/19862051.html.
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Andrade, Marina Elizabeth Barbosa. "Growth curves of the visceral organs of Saanen goats /." Jaboticabal, 2017. http://hdl.handle.net/11449/151571.
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Orientador: Izabelle Auxiliadora Molina de Almeida TeixeiraCoorientador: Carla Joice Härter
Banca: Rafael Fernandes Leite
Banca: Kleber Tomas de Resende
Resumo: Este trabalho foi realizado utilizando informações de 7 estudos, em que foram ajustadas curvas de crescimento ao desenvolvimento dos órgãos do sistema visceral de fêmeas, machos castrados e machos inteiros da raça Saanen de 0,5 a 19,5 meses de idade. Inicialmente, foram avaliados oito modelos: Regressão linear simples; Quadrático; Monomolecular; Brody; Von Bertalanffy; Logística; Gompertz; e Richards. Os dados dos órgãos viscerais (fígado, pâncreas, baço, rúmen-retículo, omaso, abomaso, intestino delgado e intestino grosso) e tecido adiposo mesentérico (TAM), foram ajustados nos modelos usando o procedimento NLMIXED do SAS. O melhor modelo ajustado foi escolhido com base no Critério de Informações Akaike corrigido para pequenas amostras (AICc) e nos coeficientes de correlação de concordância (CCC). Após a escolha do modelo que melhor ajustou a curva de crescimento dos órgãos viscerais avaliados, modelamos a variância buscando um melhor ajuste. Os parâmetros dos modelos para cada sexo foram comparados utilizando o comando CONTRAST (p < 0,10). Em geral, o modelo que melhor descreveu o crescimento de órgãos do sistema visceral foi o logístico (menor AICc e maior CCC). Quando os órgãos foram expressos em gramas, o sexo não influenciou os parâmetros das equações para predição do crescimento dos órgãos avaliados (p > 0,10), exceto o MAT (p < 0,02); em que as fêmeas apresentaram menor taxa de deposição comparada aos machos inteiros e castrados (0,318 ± 0,034 vs 0,659 ± 0,062), e um ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work was performed gathering information of 7 studies, in which growth curves were fitted to the visceral organs of female, intact male, and castrated male Saanen goats from 0.5 to 19.5 months old. Initially, eight models were assessed: Monomolecular; Simple linear regression; Quadratic; Monomolecular; Brody; Von Bertalanffy; Logistics; Gompertz; and Richards. Data of the visceral organs (liver, pancreas, spleen, rumen-reticulum, omasum, abomasum, small intestine, and large intestine) and mesenteric adipose tissue (MAT) were fitted in the models using NLMIXED procedure of SAS. The best fitted model was choosing based on the Akaike Corrected Information Criterion for small samples (AICc) and values and the concordance correlation coefficient (CCC). After choosing the model that best fitted the growth curve of the evaluated visceral organs, we modelled the variance seeking a better fit. Parameters of the models for each sex were compared using the CONTRAST statement (p < 0.10). Overall, the model that best described visceral organ growth was the logistic (i.e., lower AICc and higher CCC). When organs were expressed in grams, the sex did not influence the parameters of equations to predict the growth of the evaluated organs (p > 0.10), except for TAM (p < 0.02); females presented a lower deposition rate compared to intact males and castrated males (0.318 ± 0.034 vs 0.659 ± 0.062), and a inflection point higher than intact males and castrated males (7.65 vs 3.69 months). However, this difference between the sexes is not found when TAM is expressed in % to empty body weight (EBW). Irrespective of sex, at the beginning of growth, liver stood for 2.75 ± 0.113 % of EBW, grew (g) at a maximum rate of 0.531 ± 0.062, and its inflection point of the curve occurred at 1.7 months. The gastrointestinal t... (Complete abstract click electronic access below)
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Boillat, Carol Simone. "Investigation of gastrointestinal motility in dogs using a wireless capsule system /." [S.l.] : [s.n.], 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Kapraali, Marjo. "Prostaglandin E₂ influences the gastrointestinal endocrine cell system in the rat /." Stockholm, 1998. http://diss.kib.ki.se/search/diss.se.cfm?19980918kapr.
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Malhi, Sukbir Kaur. "Drug targeting to the gastrointestinal tract using a novel carrier system." Thesis, University of Brighton, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318729.
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Lidums, Ilmars. "Pharmacological control of transient lower oesophageal sphincter relaxations /." Title page, contents and summary only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phl715.pdf.
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Kelsey, Thomas J. "Teaching gastrointestinal history: t he efficacy of including a comprehensive endoscopic digital overview of the gastrointestinal system in a histology curriculum." Thesis, Boston University, 2013. https://hdl.handle.net/2144/12133.
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Thesis (M.A.)--Boston UniversityOver the past several decades, significant changes have been made to the methods of teaching medical histology. One of the most significant modifications is the implementation of virtual microscopy in replacement of conventional light microscopes and glass slides. This innovative method for viewing histological samples allows students to use their computers as virtual microscopes and gives them access to hundreds of relevant digital histology slides through an online database. This modification increases efficiency and gives students more time to explore clinically relevant topics. One challenge students face in a typical histology curriculum is developing a connection between the microscopic histological samples in which they are studying and their macroscale anatomical counterparts. In gastrointestinal histology in particular, the ability to bridge this gap is imperative for generating an all-encompassing understanding of this complex system. On endoscopy, the specialized mucosal surfaces of the organs of the gastrointestinal system can be thoroughly investigated. By combining high-definition endoscopic footage of the normal gastrointestinal system with histological samples, the bridge between microanatomy and macroanatomy can be established. This study investigates the implementation of a comprehensive overview of the structure and function of the gastrointestinal system using high-definition endoscopic videos and histologic samples in a graduate and medical histology curriculum. Student performance is analyzed by comparing test question performance between students who watched the video and students who did not. After a complete review of the student performance data and student feedback, it is evident that this multidimensional overview assisted students in developing a comprehensive understanding of gastrointestinal histology.
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李保能 and Po-nung Peter Lee. "Melatonin and 2-[125I]iodomelatonin binding sites in the gastrointestinal tract." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233673.
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Ng, Fook-hong. "Management of adverse gastrointestinal events in patients with anti-platelet therapy." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41290963.
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Tse, Tak-fong. "Role of RON activation on chemoresistance in gastric cancer." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38592253.
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Gunson, Rory Niall. "The development, implementation and evaluation of a real-time PCR-based diagnostic service for viral causes of infectious intestinal disease." Connect to e-thesis, 2007. http://theses.gla.ac.uk/108/.
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Thesis (Ph.D.) - University of Glasgow, 2007.Ph.D. thesis submitted to the Division of Community Based Sciences, Faculty of Medicine, University of Glasgow, 2007. Includes bibliographical references. Print version also available.
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Winter, Jack. "Studies of in situ nitrosative stress following nitrate ingestion in the human upper gastrointestinal tract." Connect to e-thesis, 2008. http://theses.gla.ac.uk/207/.
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Thesis (M.D.) - University of Glasgow, 2008.M.D. thesis submitted to the Faculty of Medicine, Division of Cardiovascular and Medical Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.
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Mitchell, Belinda Michon Hall. "Restriction endonuclease analysis of chromosomal DNA from campylobacter and helicobacter organisms." Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/25220.
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Backman, Ruth Valerie. "The effects of plantain non starch polysaccharide upon the gut bacteria." Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=131552.
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The non-starch polysaccharide (NSP) components from apple, oat, broccoli and plantain were tested as growth substrates for representatives of the major groups of intestinal bacteria, none of which was able to fully utilise the NSPs for growth. More bacteria were able to use the soluble plantain NSP fraction for growth than any other NSP tested, with the Bacteroides group showing the strongest growth response. E. coli strains isolated from healthy people and Inflammatory bowel disease (IBD) patients were all able to utilise the soluble plantain substrate to the same high extent. A wide range of commensal anaerobes were able to bind to the insoluble plantain NSP in a strain specific manner that was independent of the ability to utilize the soluble plantain NSP for growth, with E. coli binding in the highest numbers to the insoluble NSP. The effects of plantain NSP were monitored in vivo, and only the Bacteroides group increased significantly after soluble plantain supplementation. E. coli populations were volunteer-specific and unaltered after plantain supplementation. Bacteroides and E. coli were the two main groups affected by plantain NSP after the in vitro work, both of which have been implicated in IBD. Binding to, and growth on plantain may therefore selectively alter the composition of the gut microbiota in patients. Despite the stimulation of E. coli growth, addition of plantain to the diet may help to prevent colonization of the gut wall by providing this alternative binding substrate.
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Chan, Rebeca, and 陳懿雯. "A systematic review on the effectiveness of the first-line treatment of gastroesophageal reflux disease in H. pylori infected patients." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47559895.
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Helicobacter pylori (H.pylori) had been confirmed by the World Health Organization (WHO) as Group 1 carcinogens, in which it has been identified to be related with the development of gastric carcinoma. Gastroesophageal reflux disease (GERD) is less commonly found in Asia, while the number of H.pylori infection is considerably to be higher than that of the Western population. The relationship between H.pylori and GERD still remains ambiguous nowadays. One of the contributing factors affecting the level of gastric secretion might be due to the genetic cause. The aim of this review is to assess whether the current first-line therapy on GERD would be effective or not in relieving the symptoms of the patients with H.pylori infection.published_or_final_version
Community Medicine
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Master of Public Health
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Lo, Wing-joe. "Effects of neurotransmitters and peptides on gastrointestinal motility in the shark, hemiscyllium plagiosum (Bennett) /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13597322.
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Gudheti, Manasa V. Wrenn Steven Parker Dr. "Combined interaction of phospholipase C and apolipoprotein A-I with small unilamellar vesicles in the context of gallstone disease /." Philadelphia, Pa. : Drexel University, 2004. http://dspace.library.drexel.edu/handle/1860/363.
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Rachev, Petar Zahariev. "Integrated system for electromechanical modeling and functional electrical stimulation of gastrointestinal organs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65009.pdf.
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Maria, Ana Paula Judice [UNESP]. "Intervenção nutricional do estudo do envelhecimento do trato gastrointestinal em cães." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/89188.
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000735684.pdf: 2208916 bytes, checksum: fc893d8186bcdfad48c0cff2054427eb (MD5)A relação entre o envelhecimento e os componentes da dieta, carboidratos e proteínas, microbiota e produtos de fermentação no intestino, histologia e imunidade intestinal e imunidade sistêmica, são pontos importantes para a nutrição de cães, mas muito pouco estudados. Neste estudo foram analisados os efeitos da idade e das fontes de proteína e carboidrato sobre a digestibilidade dos nutrientes, produtos de fermentação, pH, microbiota e IgA das fezes, parâmetros imunológicos sanguíneos e histologia da mucosa gastrointestinal de cães. O ensaio seguiu esquema fatorial 3 x 2, com três rações e duas idades, gerando seis tratamentos experimentais. Foram empregados três blocos de 12 cães cada, sendo seis cães adultos (2,6 ± 0,9 anos) e seis idosos (10,2 ± 1,0 anos) com duas repetições por tratamento em cada bloco, totalizando seis repetições (cães) por tratamento. As rações experimentais foram: dieta com fibra insolúvel não fermentável a base de cana-de-açúcar (FC) e farinha de vísceras de frango; dieta com 30% de farelo de soja (FS), em substituição a farinha de vísceras de frango; dieta com fibra fermentável e parcialmente solúvel a base de polpa de beterraba (PBe). Os dados obtidos foram avaliados por análise de variância pelo procedimento MIXED do SAS, considerando-se os efeitos de bloco, animal e ração e suas interações. Médias foram comparadas pelo teste de Tukey (P<0,05). Os resultados de histologia da mucosa do trato digestivo foram comparados pelo teste de Kruskal-Wallis e o pós-teste de Dunn (P<0,05). Na dieta PBe houve interação entre idade e os coeficientes de digestibilidade aparente (CDA), sendo estes menores para os idosos (P<0,05). As contagens de colônias de anaeróbios totais, aeróbios totais, Lactobacillus spp e Bifidobacterium apresentaram interação idade e dieta (P<0,05). Para estas bactérias cães adultos alimentados com...
A relação entre o envelhecimento e os componentes da dieta, carboidratos e proteínas, microbiota e produtos de fermentação no intestino, histologia e imunidade intestinal e imunidade sistêmica, são pontos importantes para a nutrição de cães, mas muito pouco estudados. Neste estudo foram analisados os efeitos da idade e das fontes de proteína e carboidrato sobre a digestibilidade dos nutrientes, produtos de fermentação, pH, microbiota e IgA das fezes, parâmetros imunológicos sanguíneos e histologia da mucosa gastrointestinal de cães. O ensaio seguiu esquema fatorial 3 x 2, com três rações e duas idades, gerando seis tratamentos experimentais. Foram empregados três blocos de 12 cães cada, sendo seis cães adultos (2,6 ± 0,9 anos) e seis idosos (10,2 ± 1,0 anos) com duas repetições por tratamento em cada bloco, totalizando seis repetições (cães) por tratamento. As rações experimentais foram: dieta com fibra insolúvel não fermentável a base de cana-de-açúcar (FC) e farinha de vísceras de frango; dieta com 30% de farelo de soja (FS), em substituição a farinha de vísceras de frango; dieta com fibra fermentável e parcialmente solúvel a base de polpa de beterraba (PBe). Os dados obtidos foram avaliados por análise de variância pelo procedimento MIXED do SAS, considerando-se os efeitos de bloco, animal e ração e suas interações. Médias foram comparadas pelo teste de Tukey (P<0,05). Os resultados de histologia da mucosa do trato digestivo foram comparados pelo teste de Kruskal-Wallis e o pós-teste de Dunn (P<0,05). Na dieta PBe houve interação entre idade e os coeficientes de digestibilidade aparente (CDA), sendo estes menores para os idosos (P<0,05). As contagens de colônias de anaeróbios totais, aeróbios totais, Lactobacillus spp e Bifidobacterium apresentaram interação idade e dieta (P<0,05). Para estas bactérias cães adultos alimentados ...
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Duque, Ana Luiza Rocha Faria. "Influência do suco de laranja na microbiota intestinal humana /." Araraquara, 2016. http://hdl.handle.net/11449/138094.
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Orientador: Katia SivieriCoorientador: Magali Monteiro da Silva
Banca: Elaine Cristina Pereira de Martinis
Banca: Thais Borges Cesar
Resumo: A microbiota intestinal apresenta impacto direto na saúde do hospedeiro sendo fortemente influenciada pela dieta. O consumo de suco de laranja vem sendo associado à redução do risco de desenvolvimento de doenças crônicas, principalmente devido à presença de compostos bioativos. Os compostos bioativos presentes no suco de laranja, especialmente os polifenóis, também podem estar relacionados com a composição e o metabolismo da microbiota intestinal. O objetivo desse trabalho foi avaliar a influência do suco de laranja fresco e pasteurizado sobre a microbiota intestinal usando o Simulador do Ecossistema Microbiano Humano (SEMH®). O SEMH® foi utilizado para investigar a fermentação do suco de laranja ao longo do cólon e para avaliar as alterações na composição e no metabolismo microbiano. A atividade antioxidante dos sucos e das amostras dos compartimentos do SEMH® também foi avaliada. Foi observado no tratamento com suco de laranja fresco aumento (p≤0,05) das populações de Lactobacillus spp., Enterococcus spp., Bifidobacterium spp. e Clostridium spp. e diminuição (p≤0,05) de enterobactérias, enquanto no tratamento com suco de laranja pasteurizado houve aumento (p≤0,05) da população de Lactobacillus spp. e diminuição (p≤0,05) de enterobactérias. A análise de PCR-DGGE mostrou redução dos valores de riqueza da população de bactérias totais para ambos os sucos. Em relação ao metabolismo microbiano, foi observado aumento (p≤0,05) da produção de ácidos graxos de cadeia curta (AGCC) e diminuição (p≤0,05) do conteúdo de íons amônio no tratamento com os sucos de laranja fresco e pasteurizado. A atividade antioxidante das amostras dos compartimentos do SEMH® no tratamento com os sucos de laranja foi elevada, com ligeira redução em comparação àquela do suco fresco e do suco pasteurizado....
Abstract: The gut microbiota has a direct impact on host's health being strongly influenced by diet. Orange juice consumption has been associated with a reduced risk of chronic diseases, largely because of the presence of bioactive compounds. The bioactive compounds present in orange juice, particularly polyphenols, may also be associated with the composition and metabolism of gut microbiota. The aim of this work was to evaluate the influence of fresh orange juice and pasteurized orange juice on gut microbiota using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®). SHIME® was used to investigate orange juice fermentation throughout the colon and to assess changes in microbial composition and microbial metabolism. Antioxidant activity of the SHIME® vessels and juice was also evaluated. An increase (p≤0.05) in Lactobacillus spp., Enterococcus spp., Bifidobacterium spp. and Clostridium spp. population was observed in fresh orange juice treatment, as well as a reduction (p≤0.05) in enterobacteria. Regarding pasteurized orange juice treatment, an increase (p≤0.05) in Lactobacillus spp. population and a decrease (p≤0.05) in enterobacteria was observed. The PCR-DGGE analysis showed a reduction in total bacteria population richness values on both juices. According to microbial metabolism, an increasing (p≤0.05) of short-chain fatty acids (SCFA) production and decreasing (p≤0.05) of ammonium was observed for two juices treatments evaluated. The antioxidant activity of the samples from the SHIME® vessels in the orange juice treatments was high, with a slight reduction compared to that of fresh juice and pasteurized juice. Both fresh and pasteurized orange juice influenced on gut microbiota according to Principal Component Analysis (PCA), which enabled to differentiate the orange juice treatments from control and washout periods. Both juices ...
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Maria, Ana Paula Judice. "Intervenção nutricional do estudo do envelhecimento do trato gastrointestinal em cães /." Jaboticabal, 2013. http://hdl.handle.net/11449/89188.
Full textAbstract:
Orientador: Aulus Cavalieri CarciofiBanca: Lilian Rose Marques de Sá
Banca: Luciana Domingues de Oliveira
Resumo: A relação entre o envelhecimento e os componentes da dieta, carboidratos e proteínas, microbiota e produtos de fermentação no intestino, histologia e imunidade intestinal e imunidade sistêmica, são pontos importantes para a nutrição de cães, mas muito pouco estudados. Neste estudo foram analisados os efeitos da idade e das fontes de proteína e carboidrato sobre a digestibilidade dos nutrientes, produtos de fermentação, pH, microbiota e IgA das fezes, parâmetros imunológicos sanguíneos e histologia da mucosa gastrointestinal de cães. O ensaio seguiu esquema fatorial 3 x 2, com três rações e duas idades, gerando seis tratamentos experimentais. Foram empregados três blocos de 12 cães cada, sendo seis cães adultos (2,6 ± 0,9 anos) e seis idosos (10,2 ± 1,0 anos) com duas repetições por tratamento em cada bloco, totalizando seis repetições (cães) por tratamento. As rações experimentais foram: dieta com fibra insolúvel não fermentável a base de cana-de-açúcar (FC) e farinha de vísceras de frango; dieta com 30% de farelo de soja (FS), em substituição a farinha de vísceras de frango; dieta com fibra fermentável e parcialmente solúvel a base de polpa de beterraba (PBe). Os dados obtidos foram avaliados por análise de variância pelo procedimento MIXED do SAS, considerando-se os efeitos de bloco, animal e ração e suas interações. Médias foram comparadas pelo teste de Tukey (P<0,05). Os resultados de histologia da mucosa do trato digestivo foram comparados pelo teste de Kruskal-Wallis e o pós-teste de Dunn (P<0,05). Na dieta PBe houve interação entre idade e os coeficientes de digestibilidade aparente (CDA), sendo estes menores para os idosos (P<0,05). As contagens de colônias de anaeróbios totais, aeróbios totais, Lactobacillus spp e Bifidobacterium apresentaram interação idade e dieta (P<0,05). Para estas bactérias cães adultos alimentados com ...
Abstract: A relação entre o envelhecimento e os componentes da dieta, carboidratos e proteínas, microbiota e produtos de fermentação no intestino, histologia e imunidade intestinal e imunidade sistêmica, são pontos importantes para a nutrição de cães, mas muito pouco estudados. Neste estudo foram analisados os efeitos da idade e das fontes de proteína e carboidrato sobre a digestibilidade dos nutrientes, produtos de fermentação, pH, microbiota e IgA das fezes, parâmetros imunológicos sanguíneos e histologia da mucosa gastrointestinal de cães. O ensaio seguiu esquema fatorial 3 x 2, com três rações e duas idades, gerando seis tratamentos experimentais. Foram empregados três blocos de 12 cães cada, sendo seis cães adultos (2,6 ± 0,9 anos) e seis idosos (10,2 ± 1,0 anos) com duas repetições por tratamento em cada bloco, totalizando seis repetições (cães) por tratamento. As rações experimentais foram: dieta com fibra insolúvel não fermentável a base de cana-de-açúcar (FC) e farinha de vísceras de frango; dieta com 30% de farelo de soja (FS), em substituição a farinha de vísceras de frango; dieta com fibra fermentável e parcialmente solúvel a base de polpa de beterraba (PBe). Os dados obtidos foram avaliados por análise de variância pelo procedimento MIXED do SAS, considerando-se os efeitos de bloco, animal e ração e suas interações. Médias foram comparadas pelo teste de Tukey (P<0,05). Os resultados de histologia da mucosa do trato digestivo foram comparados pelo teste de Kruskal-Wallis e o pós-teste de Dunn (P<0,05). Na dieta PBe houve interação entre idade e os coeficientes de digestibilidade aparente (CDA), sendo estes menores para os idosos (P<0,05). As contagens de colônias de anaeróbios totais, aeróbios totais, Lactobacillus spp e Bifidobacterium apresentaram interação idade e dieta (P<0,05). Para estas bactérias cães adultos alimentados ...
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羅穎祖 and Wing-joe Lo. "Effects of neurotransmitters and peptides on gastrointestinal motilityin the shark, hemiscyllium plagiosum (Bennett)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B3123382X.
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Anderson, Susan A. "Maternal dietary glucose intake affects neonatal gastrointestinal development in rats." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0029/MQ50707.pdf.
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Hamilton, Peter William. "A morphometric assessment of pre-neoplastic and neoplastic conditions in the gastrointestinal system." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335975.
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Addisu, Anteneh. "Natriuretic peptides as a humoral link between the heart and the gastrointestinal system." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002406.
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