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1
White, J. S. "Models of intestinal barrier function and their application in the study of biliary obstruction". Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368529.
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Vianna, Karina Costa Maia. "Tumor estomal gastrointestinal (GIST)". reponame:Repositório Institucional da UFPR, 2012. http://hdl.handle.net/1884/26630.
Testo completoAbstract (sommario):
Resumo: Introdução: Os tumores estromais gastrointestinais (GIST) são neoplasias raras que se originam das células intersticiais de Cajal .A última década foi de grande avanço com o esclarecimento dos mecanismos moleculares, seguido da terapia molecular, que propiciaram um grande aumento na sobrevida. Objetivo: Avaliar a experiência do Hospital de Clínicas de Curitiba no tratamento do GIST localizado e avançado, com análise das características clínicas e anatomo-patológicas e uso do imatinibe. Metodologia: Estudo retrospectivo de 32 pacientes com diagnóstico de GIST por imunohistoquímica, c-Kit positivo, no período de 2003 a 2008 Resultados: Os dados evidenciaram que a idade mediana foi de 66 anos, o tamanho mediano de 8,4 cm e as localizações mais frequentes foram estômago em 46,9% e intestino delgado em 40,9%. Considerado com alto risco de agressividade 37,5% dos pacientes. Do grupo total, 23 pacientes apresentavam doença localizada no diagnóstico, sendo que 39,1% recaíram, e 9 pacientes doença avançada. O seguimento mediano foi de 43,7 meses. A sobrevida global em 5 anos no grupo total foi de 56,2%, sendo que na doença localizada foi de 73,8% e na doença avançada foi de 37,5% (p=0,03). Não foi observado impacto dos fatores prognósticos na sobrevida. A utilização do imatinibe ocorreu em 16 pacientes, 43,8% por metástase inicial, 37,5% por recaída a distância, 12,5% por recaída local e 6,2% por margem cirúrgica comprometida. A sobrevida global com uso do imatinibe mediana foi de 53 meses e a sobrevida livre de primeira progressão de 32,9 meses. Ocorreu uma boa tolerabilidade ao imatinibe, com 2 pacientes com toxicidade grau 3 e apenas dois pacientes utilizaram o sunitinibe. Conclusão: A maioria dos tumores foram grandes, de localização gástrica e de alto risco de agressividade. A taxa de recaída na doença localizada foi alta. E a sobrevida global dos pacientes de doença localizada e que utilizaram o imatinibe foi considerada satisfatória.
3
Thoree, Cheetranjan Vinay. "Characterisation of gastrointestinal microparticles". Thesis, King's College London (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.555927.
Testo completoAbstract (sommario):
Intestinal Peyer's patches, through their specialized M cell-rich epithelium, can act as a portal of entry for bacteria, viruses, macromolecules and particles. Particles can be further classified as exogenous particles such as those derived from the diet in the form of food additives or endogenous particles which result from calcium and phosphate precipitation in the mid-distal intestinal lumen. Although exogenous dietary particles have been found to accumulate in "pigment cells" at the base of the human Peyer's patch, little is known about calcium phosphate particles. This thesis aimed (i) to investigate and compare the micro-anatomical site of exogenous and endogenous particles within the Peyer's patch, and (ii) to analyse the phenotype of cells involved in their uptake. Following an Introduction chapter (Chapter 1) and Methods chapter (Chapter 2), the focus of chapter 3 was to look for the presence of both calcium phosphate and exogenous particles in human intestinal Peyer's patches using the Von Kossa staining method and dark field microscopy, respectively. The elemental makeup of the endogenous particles was investigated by X-Ray Microanalysis (XRMA). This study revealed a sub-epithelial Peyer's patch dome-associated population of Von Kossapositive particle cells, the majority of which appeared to be calcium-rich, and more especially calcium- and phosphorus- rich. Exogenous particles associated with the usual basal pigment cells could similarly be found in the sub-epithelial dome cells and suggested that the exogenous particles made their way through the patch via intermediary cells. Following work concentrated on the phenotyping of cells responsible for the uptake of exogenous and endogenous particles (Chapters 4 and 5, respectively). Pigment cells of the Peyer's patch base were found to be macrophages, chiefly of a mature phenotype, and appeared metabolically and immunologically of low activation status. In contrast, calcium phosphate particles were found mainly in dendritic cells of the sub epithelial dome region of the Peyer's patch. The cell phenotype (CDIlc+, CDl lb+) was consistent with immune tolerance-inducing dendritic cells reported in the literature - the specific mechanism being induction of regulatory T cells. I have speculated on how the uptake of endogenous particles may influence such process.
4
Ullah, Sana. "Factors governing gastrointestinal motility". Thesis, University of Hull, 2012. http://hydra.hull.ac.uk/resources/hull:7166.
Testo completoAbstract (sommario):
Introduction: The reasons for the rapid resolution of diabetes (DM) following bariatric surgery in a significant proportion of patients with morbid obesity remain unclear. This thesis investigates the putative role of changes in gastrointestinal (GI) motility and GI hormones as well as the possible significance of alterations in energy expenditure that occur as a consequence of weight loss. Methodology: My preliminary studies involved a systematic review of GI motility in obesity, and retrospective studies measuring GI motility with alternative methods including capsule endoscopy and hydrogen breath test. Subsequent to this I measured changes in GI motility in two very different patient cohorts; one following bariatric surgery for morbid obesity and the other a group of patients with proven gastroparesis treated with gastric neuromodulation (GNM). Parallel to the above I conducted studies of indirect calorimetry in these patients in an attempt to determine if changes in energy expenditure which occur as a consequence of weight loss were significant. Results: In our prospective study temporary GNM significantly improved gastric emptying and nutritional intake. There was conclusive evidence to causally relate alterations in GI motility and Glucagon like peptide -1 (GLP-1) with weight loss and resolution of DM following bariatric surgery. An interesting "spin off" result of my studies was validation of capsule endoscopy (CE) as a means of assessing GI motility. My results obtained from measure if indirect calorimetrty clearly show that standard equations tend to over estimate the energy requirements of this group. The implications of this are discussed. Conclusions: 1. Fast pouch emptying; an early and exaggerated GLP-1 response contributes in resolution of type 2 diabetes following RYGB. 2. GNM is an effective treatment for gastroparesis. 3. Capsule endoscopy may be used to assess GI motility. 4. Prediction equations over estimate energy requirements in morbidly obese patients.
5
Silva, Vera Lisa Generosa da. "Estase gastrointestinal no coelho". Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4935.
Testo completoAbstract (sommario):
Dissertação de Mestrado Integrado em Medicina VeterináriaActualmente, como o coelho é um animal de estimação frequente, é importante que o Médico Veterinário esteja bem informado sobre este paciente "exótico", para que assim o consiga acompanhar devidamente. Uma das urgências mais comum neste animal, é a estase gastrointestinal (GI), que é uma doença adquirida, em que ocorre uma diminuição ou interrupção da motilidade do tracto GI. É dos problemas mais desafiantes com que o veterinário poderá ser confrontado, sendo o seu tratamento complexo e a resposta terapêutica do paciente, lenta. Esta dissertação resultou de um estágio curricular, com a duração de seis meses, realizado no Centro Veterinário de Exóticos do Porto. São apresentados e discutidos dez casos clínicos de estase GI, em coelhos de estimação, presentes à consulta durante esse período. Os sinais mais frequentemente observados nestes animais, incluíram anorexia, diminuição/ausência na produção de fezes e dilatação abdominal. A principal causa da estase GI nestes pacientes deveu-se a uma dieta inadequada, no entanto, outras etiologias frequentes foram, ainda, o stress e a dor (muito vulgarmente causada por problemas dentários). De acordo com os casos clínicos observados, é de salientar a importância da precocidade na administração do tratamento adequado, para que assim se consiga restabelecer a motilidade GI, não descurando, no entanto, o diagnóstico da etiologia primária, que deve ser realizado simultaneamente.
ABSTRACT - Gastrointestinal stasis in rabbit - Nowadays, the rabbit is a fairly common pet, for this reason, it is important for the Veterinarian, to be updated on this “exotic” patient, in order to handle and treat it, accordingly. One of the most common emergencies in this species, is gastrointestinal stasis, an acquired disease, where reduced to inexistent GI tract motility occurs. It is one of the most challenging problems the veterinarian might be presented with, due to its complex treatment and slow recovery of the patient. This essay was the result of a six months training, on Centro Veterinário de Exóticos do Porto. Ten GI stasis clinical cases, on rabbit pets, are presented and discussed; all of them took place during the training. The most commonly observed signs included anorexia, reduced /no faeces output and abdominal enlargement. The main cause for GI stasis in these patients, was an inadequate diet, although, other frequent aetiologies were stress and pain (commonly caused by dental problems). According to the analyzed clinical cases, it is mandatory to emphasize the importance of early adequate treatment administration, so GI motility might be re-established. Nevertheless, diagnosing the primary aetiology must take place simultaneously.
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Шевченко, Володимир Порфирович, Владимир Порфирьевич Шевченко, Volodymyr Porfyrovych Shevchenko, Z. Jawad e O. Amazu. "Nsaid - related gastrointestinal bleeding". Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/4899.
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7
Tekkis, Paris Procopiou. "Risk-adjustment in gastrointestinal surgery". Thesis, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406906.
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Stevenson, Diane J. "P2X7, inflammation and gastrointestinal disease". Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/28897/.
Testo completoAbstract (sommario):
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.
9
Khosla, Rajiv. "Gastrointestinal transit of dosage forms". Thesis, University of Nottingham, 1987. http://eprints.nottingham.ac.uk/12741/.
Testo completoAbstract (sommario):
This thesis describes the results from a series of studies designed to evaluate the gastrointestinal transit of oral dosage forms. The transit of placebo pellet and tablet formulations was monitored using the technique of gamma scintigraphy. The formulations were radiolabelled with either technetium-99m or indium-lil. Four parameters, two physiological and two pharmaceutical, were selected for investigation. All the studies were conducted in healthy male volunteers. The first study examined the influence of the supine position on the gastric emptying of pellets in fasted and fed subjects. There was no marked difference between the supine and control gastric emptying data. As would be expected, food had a significant effect on gastric emptying. The influence of the time of day of administration on the gastrointestinal transit of pellets was investigated in fasted subjects. Transit of the pellets was not affected by their time of administration. The effect of the putative bioadhesive, polycarbophil, on the gastrointestinal transit of a pellet formulation was studied in fasted subjects. The pellets emptied from the stomach, rapidly and in an exponential manner. A set of studies was conducted to evaluate the transit of tablets in fed and fasted subjects. Tablet size did not affect gastric emptying, although there was an increase in the variability of gastric emptying with increasing tablet size. Food had a marked effect on gastric emptying. The rate of emptying was related to the energy content of the meal. Tablet size did not appear to be a determinant of transit through the ileocaecal sphincter. The colon transit and dispersion of the tablets was examined. Neither the ingestion of food nor defecation appeared to alter the rate of transit through the colon.
10
Daly, R. "Gastrointestinal bacteria : attachment and interactions". Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398156.
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11
Pye, G. "Gastrointestinal pH and colorectal neoplasia". Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381466.
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Porter, Timothy Robin. "Molecular genetics of gastrointestinal cancer". Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273741.
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13
Yates, Catherine Ann. "Gastrointestinal development and riboflavin deficiency". Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312293.
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14
Woloshynowych, Maria. "Psychological preparation for gastrointestinal endoscopy". Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287454.
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15
Poxon, Valerie Anne. "Gastrointestinal inflammation and mucus biosynthesis". Thesis, Birmingham City University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334499.
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16
Losson, B. J. "Immunological unresponsiveness to gastrointestinal nematodes". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372886.
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17
Mrowicki, Anna. "Disordered eating in gastrointestinal disorders". Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/88064/.
Testo completoAbstract (sommario):
This thesis consists of three chapters, a literature review, an empirical paper, and a reflective paper. Chapter one is a critical review of case study research on Disordered Eating (DE) in Gastrointestinal disorders (GId). Following both database and manual searches, twelve case study reports, describing 29 cases, were included and reviewed. The case study data shows there be a relationship between DE and GId, though the nature and direction of this relationship remains unclear. Possible risk factors for the onset of DE behaviours in the GId population are identified and discussed, as are suggestions for future research. Chapter two is a quantitative research study looking at DE in people with Crohn’s Disease (CD), compared to the general population. Participants in both groups (CD and control) completed self-reported, standardised measures of eating attitudes/behaviours and mood. The prevalence of DE was shown to be higher for people with CD compared to the general population, with females with CD shown to be most at risk of developing DE behaviours. In addition, anxiety and depression in children is highlighted as a possible risk factor for the development of DE in CD, in children. Clinical implications and directions for future research are discussed. Chapter three is a reflective account exploring the researcher’s research journey, from beginning to end. In this paper the choice of thesis topic is discussed, as are the researcher’s associated thoughts and feelings. The researcher’s epistemological position in relation to the methodology and natural style is also explored.
18
LePard, Kathy Jean. "Serotonergic control of gastrointestinal function /". The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487859879938908.
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Partridge, Stephen. "The gastrointestinal absorption of lead". Thesis, Aston University, 1986. http://publications.aston.ac.uk/14504/.
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20
Kabke, Geórgia Brum. "Escore prognostico de avaliação nutricional em pacientes com tumores do trato gastrointestinal superior". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/110236.
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Bennett, Ethelle. "Functional gastrointestinal disorders relations between psychosocial factors, symptoms and sensorimotor disturbance /". Connect to full text, 1999. http://hdl.handle.net/2123/410.
Testo completoAbstract (sommario):
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.
22
Filho, Dilson da Silva Pereira. "Desinfecção de endoscópios através da utilização de água ácida eletrolítica (pesquisa prospectiva e in vitro)". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/5/5154/tde-09102014-093609/.
Testo completoAbstract (sommario):
O Glutarldeído é usado como desinfetante de endoscópios, mas por ser irritante, deve ser substituído por outro produto alternativo. A água ácida eletrolisada (AAE) possui efeito bactericida, tecnologia essa desenvolvida no Japão para lavadoras de endoscópios. No nosso estudo, a contaminação endoscópica após o seu uso clínico foi examinada através de cultura para bactérias, micobactérias e fungos, tanto antes quanto após a desinfecção com glutaraldeído por 20 minutos ou água ácida eletrolizada por 7 minutos. As colônias de bactérias foram identificadas e contadas após 48 horas de incubação a 37o C. A contaminação microbiana dos colonoscópios foi detectada após 30 (trinta) procedimentos endoscópicos, contudo o tratamento com a AAE conseguiu erradicar todos os microorganismos. A atividade microbiana da AAE mostrou-se ser similar ao glutaraldeído a 2%. Os resultados indicam que a AAE é um eficiente desinfetante depois da limpeza mecânica dos colonoscópios, podendo ser usado nas unidades de endoscopias como uma alternativa ao glutaraldeídoEfficient disinfection is important given the multiplicity of bacterial exposures to equipment used in endoscopy. Glutaraldehyde is used as a disinfectant for endoscopes, but is an irritant and so should be replaced by an alternative. Electrolized cid water (EAW) has bactericidal effect, and an endoscopic washing device using EAW has been developed in Japan. In our study, endoscopic contamination after clinical use was examinated by culture for bacteria, mycobacteria and fungi before and after exposing to glutaraldehyde (20min) and electrolized acid water (7min). The bacterial colonies were identified and counted after 48 hours of incubation at 37oC. Microbial contamination of colonoscopes was detected after 30 endoscopic procedures, but the treatment of the endoscope with EAW eradicated the microbes. The microbicidal activities of EAW was similar to that of glutaraldehyde. These results indicate that EAW is effective disinfectant after mechanical cleaning of colonoscopes, and can, therefore, be used in the endoscopy unit as an alternative to glutaraldehyde
23
Dadgar, Anoushiravan. "Studies on rat gastrointestinal neuropeptide Y". Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27410.
Testo completoAbstract (sommario):
A sensitive and specific radioimmunoassay (RIA) for Neuropeptide Y (NPY) was developed and quantitation, characterization and release studies were performed.
The development of the RIA required the purification of the NPY tracer due to both multiple iodinated products resulting from the five tyrosine residues in its amino acid sequence, and the presence of unlabelled NPY. Ion-exchange and reverse phase high performance chromatography (HPLC) purification of ¹²⁵I-NPY were performed. Optimal purification of ¹²⁵I-NPY was achieved using a HPLC with a μBondapak C₈ column and a 45-50% acetonitrile concentration gradient. A polyethylene glycol separation technique was used in conjunction with the HPLC purified tracer to improve assay conditions.
Although many studies aimed at elucidating the actions of NPY have been performed, little information is available on the distribution of gastrointestinal (GI) NPY in the rat. Therefore the NPY-immunoreactivity (IR) in extracts of the various regions of the GI tract were determined using the developed RIA. The tissue content of NPY was found to be highest in the various segments of the rat stomach, with a decreasing trend in NPY-IR down the GI tract until the level of the ascending colon where an increase was detected. Characterization studies on the tissue extracts were performed using gel filtration chromatography and HPLC. One immunoreactive species was detected in the corpus and ileum extracts using gel filtration chromatography, and in the corpus and colon extracts using HPLC. This immunoreactive species eluted in a position similar to synthetic porcine NPY and later than peptide YY (PYY).
In the physiological investigation of the the role of neuropeptides in the regulation of GI functions, release studies are crucial. The presence of high levels of NPY-IR in the stomach allowed the investigation of the release mechanisms of NPY in the perfused isolated rat stomach. However, due to the low basal secreted levels of NPY in comparison with other gastric peptides, as well as the enzymatic degradation and/or peptide uptake that occurs in the stomach vasculature, certain steps had to be taken to allow for the detection of the endogenously released peptide. Sep Pak extraction was found to be required to concentrate the endogenously released peptide. Proteolytic inhibitors were also added to the perfusate to reduce enzymatic degradation. A low basal level of NPY was detected which ranged from 98 to 147 fmole/min. Neuropeptide Y was found to be released into the gastric vasculature in response to high potassium depolarization.
A few studies have been performed on cholinergic effects on NPY release, however no direct release studies have been performed on NPY-containing neurones innervating the stomach. Therefore, the actions of cholinergic agonists and antagonists on NPY secretion in the isolated perfused rat stomach were investigated. Acetylcholine and the nicotinic ganglionic agonist dimethyl-phenyl-piperazinium (DMPP) stimulated NPY secretion. The acetylcholine-stimulated secretion was not blocked by the cholinergic muscarinic antagonist atropine and was partially blocked by the ganglionic cholinergic antagonist hexamethonium.
The effects of α- and β-adrenergic agonists and antagonists on NPY secretion into the stomach vasculature were investigated in order to elucidate possible adrenergic release mechanisms. There were conflicting results on the α-adrenergic release of NPY. Both the α-adrenergic antagonist phentolamine and the agonist phenylephrine had a stimulatory effect on NPY secretion in the stomach. The β -adrenergic agonist isoproterenol had a stimulatory effect on NPY release. The β -adrenergic antagonist propranolol caused an initial small increase in mean NPY levels followed by a decrease, but this was not found to be statistically significant.
These studies demonstrated the presence of NPY in the GI tract of the rat with the highest content being in the rat stomach. There are cholinergic stimulatory mechanisms involved in the secretion of NPY which are partially ganglionically mediated. The results did not conclusively demonstrate as to whether there is an α-adrenergic stimulatory or
inhibitory action on NPY-containing neurones in the gut, however preliminary release studies suggest there is a β-adrenergic stimulatory mechanism involved in NPY secretion.Medicine, Faculty of
Cellular and Physiological Sciences, Department of
Graduate
24
Brink, Gijs Robert van den. "Morphostasis of the adult gastrointestinal tract". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2002. http://dare.uva.nl/document/85925.
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Georges, Jane Marie. "Distressing gastrointestinal symptoms in postmenopausal women /". Thesis, Connect to this title online; UW restricted, 1991. http://hdl.handle.net/1773/7275.
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Crooks, Colin J. "The epidemiology of upper gastrointestinal bleeding". Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13394/.
Testo completoAbstract (sommario):
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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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.
Testo completoAbstract (sommario):
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.
28
Riddoch, C. J. "Exercise-induced gastrointestinal symptoms : hormonal involvement". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335621.
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29
Henry, Brian T. "The barrier function of gastrointestinal mucus". Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334550.
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30
Young, Catriona Jean. "Modulated enzyme expression in gastrointestinal nematodes". Thesis, University of Glasgow, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318123.
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31
Macadam, Anglea Brenda. "Drug targeting in the gastrointestinal tract". Thesis, University of Brighton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306400.
Testo completo
32
Reid, Keith. "Gastrointestinal motility in vection induced nausea". Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299548.
Testo completo
33
Patterson, David Mark. "Caprine responsiveness towards gastrointestinal nematode infection". Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/15600.
Testo completoAbstract (sommario):
Studies were conducted using Scottish cashmere goats which were segregated into responsive and non-responsive individuals on the basis of ranked faecal egg count following artificial and natural gastrointestinal nematode infection. These studies demonstrate that caprine responsiveness is a relatively stable and heritable characteristic, largely unaffected by season and mode or site of infection. Initial comparative studies showed does to be considerably more susceptible to mixed artificial teladorsagia circumcincta and Trichostrongylus vitrinus infection than were ewes or worm-naive lambs. This was reflected in distinct differences in mucosal mast cell (MMC) and glouble leukocyte (GL) populations, the does having more GLs but many fewer MMCs than ewes. Theses differences together with the very low sheep mast cell proteinase concentrations recovered from doe tissue suggest that there are important functional differences in the mast cell responses of sheep and goats. The responses of breeding male and female goats were very consistent, with individuals occupying the same position of relative responsiveness while on pasture and after artificial challenge. Differences in the susceptibility of responders and non-responders were apparent in egg count following natural and artificial infection and selection was largely supported by worm burdens recovered after artificial challenge. There was a tendency for enhanced responsiveness to be associated with increased tissue eosinophil and GL numbers though this relationship wasn't very strong. However, responders were able to mount a more rapid and vigorous peripheral eosinophil response than were non-responders suggesting that peripheral eosinophil levels may be indicative of the ability of the host to respond to infection. Analysis of the cellular traffic of the gastric lymph showed that more resistant individuals were responding earlier. Results obtained from the first generation yearlings from the helminth-line showed that under the conditions encountered in these studies increased resistance to gastrointestinal nematode infection in Scottish cashmere goats is a heritable phenomenon with a heritabililty estimate (0.37) similar to those of production traits for which selection has been successful. Over the early stages of the programme selection for enhanced resistance appears to have had no detrimental effect upon productivity.
34
Karpathakis, A. "Molecular profiling of gastrointestinal neuroendocrine tumours". Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1461038/.
Testo completoAbstract (sommario):
Small intestinal neuroendocrine tumours (SI NETs) are the most common malignancy of the small intestine, however they remain poorly characterised and the underlying pathogenic mechanisms driving disease development have yet to be elucidated. Whole genome and exome sequencing has suggested SI NETs to be mutationally quiet, with the most frequent mutation in Cyclin Dependent Kinase 1B occurring in only 8% of tumours, suggesting mechanisms other than genetic mutations may be responsible for driving SI NET tumourigenesis. Using integrated genomic and epigenomic analysis three distinct somatic copy number alteration (SCNA) profiles of SI NET were identified. The largest subgroup characterised by loss of heterozygosity at chromosome 18, negative CpG island methylator phenotype (CIMP) status, and the presence of CDKN1B mutations, is associated with improved clinical outcomes. A novel Multiple-SCNA signature has been described which defines a smaller subgroup of SI NETs and is characterized by significantly (p=0.04) reduced progression-free survival. A panel of 21 recurrently epigenetically dysregulated genes has been identified, and these represent putative novel pathogenic drivers for SI NET tumourigenesis and candidate novel biomarkers. Epigenetically dysregulated genes identified at a recurrence rate of 80-100% include gastric inhibitory polypeptide receptor (GIPR)(73.5%) – a target for novel imaging techniques in NETs, CDX1 (85.7%), CELSR3 (83.7%), FBP1 (83.7%), PCSK1 (67.3%) and TRIM15 (63.3%). The utility of methylated circulating tumour DNA analysis, and molecular profiling of circulating tumour cells as novel non-invasive biomarkers in SI NETs have been demonstrated. This is the first comprehensive integrated molecular analysis of SI NETs, providing evidence for epigenetic rather than mutational events in addition to SCNAs as drivers of SI NET development. These findings will facilitate improved patient management, treatment selection and prognostication.
35
Moreira, Ricardo Filipe Silva. "Imunonutrição em doentes com cancro gastrointestinal". Bachelor's thesis, [s.n.], 2013. http://hdl.handle.net/10284/4272.
Testo completoAbstract (sommario):
Trabalho Complementar apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de licenciado em Ciências da NutriçãoObjetivo: Fazer uma breve revisão da literatura sobre a importância da nutrição artificial, nomeadamente a imunonutrição, por via entérica, em doentes com cancro gastrointestinal, sujeitos ou não a cirurgia. Metodologia: Foi realizada uma pesquisa na base de dados da National Library of Medicine PUBMed-Medline e B-on, entre Abril e Outubro de 2013, utilizando-se os termos de pesquisa: “immunonutrition in gastrointestinal cancer surgery”, “enteral immunonutrition gastrointestinal cancer surgery operative”, “enteral immunonutrition gastrointestinal cancer preoperative”, “enteral immunonutrition gastrointestinal cancer perioperative” e “enteral immunonutrition gastrointestinal cancer postoperative”. Ao resultado da pesquisa foram aplicados os seguintes critérios de exclusão: - artigos que não estivessem escritos em inglês ou em português - artigos que não iam de encontro ao assunto em questão Além dos artigos, foram utilizadas revistas, livros científicos e alguns locais de internet. Resultados: Vários estudos demonstram que a imunonutrição é superior à nutrição padrão no que respeita à restauração da imunidade ajudando a modular a reação inflamatória, principalmente, em pacientes sujeitos a grandes cirurgias. A imunonutrição entérica, utilizando arginina, nucleótidos e glutamina, quando administrada no pré e pós-operatório é de grande valor clínico, nomeadamente em pacientes desnutridos. No pós-operatório, qualquer tipo de dieta imunomoduladora beneficia significativamente o paciente mas apenas em casos de desnutrição. Em pacientes, com cancro gastrointestinal, que recebem o suporte nutricional, a distribuição de nutrientes por via entérica é mais eficaz e mais económica do que a via parentérica. Conclusões: Comparado com a nutrição entérica padrão, a imunonutrição por via entérica pode melhorar os mecanismos de defesa do organismo do doente com cancro gastrointestinal e modular a ação inflamatória pós cirurgia. Vários estudos comprovam que a imunonutrição entérica pré-operatória, actua, reduzindo as complicações, a morbilidade e a mortalidade no pós-operatório, encurtando o tempo de internamento pós-cirurgia e assim reduzindo os custos na saúde. Em suma, a sua utilização tem uma boa relação custo-benefício. Objective: To make a brief review of the literature about the importance of artificial nutrition, specifically, enteral immunonutrition in patients with gastrointestinal cancer, whether or not subjected to surgery. Methodology: It was performed a literature research in the database of the National Library of Medicine PubMed, Medline, and B-on, between April and October 2013, using the following terms: "Immunonutrition in gastrointestinal cancer surgery", "enteral immunonutrition gastrointestinal cancer surgery operative", "enteral immunonutrition gastrointestinal cancer preoperative ", "enteral immunonutrition gastrointestinal cancer perioperative" and "enteral immunonutrition gastrointestinal cancer postoperative." To the outcome of the research were applied the following exclusion criteria: - articles that were not written in English or Portuguese, - articles that were not related to the subject matter, In addition to the articles, were used journals, scientific books and some internet sites. Results: Several studies have shown that immunonutrition is better than the standard nutrition, helping to restore the immunity and modulating the inflammatory reaction namely in patients who have undergone major surgery. The enteric immunonutrition, using arginine, glutamine and nucleotides, administered preoperatively and postoperatively is a promising way of nutritional support particularly in malnourished patients. Postoperatively, any kind of immunomodulatory diet significantly benefits the patient but only in cases of malnutrition. In patients, with gastrointestinal cancer, receiving nutritional support, the enteral distribution of nutrients is more effective and economical than the parenteral route. Conclusions: Compared with standard enteral nutrition, enteral immunonutrition can improve the defense mechanisms of the patient with gastrointestinal cancer and modulate inflammatory reaction, after surgery. Several studies have shown that preoperative enteral immunonutrition improves postoperative outcome by reducing postoperative complications, morbidity and mortality in the postoperative period, shortening the hospital stay after surgery and thus reducing health costs. So, it as a good cost-benefit ratio.
36
Eden, Kristin Beth. "Noncanonical NF-KB in Gastrointestinal Disease". Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/86127.
Testo completoAbstract (sommario):
Noncanonical NF-KB is an alternative NF-KB pathway that is critically involved in the development and maturation of the adaptive immune system. As such, it has typically been studied in B and T cell biology without application to complex organ systems such as the gut. The following work explores the contribution of noncanonical NF-KB to inflammatory and neoplastic disease in the gastrointestinal (GI) system, as well as the effects of its loss on GI health. Chapter 1 opens with an overview of gastrointestinal homeostasis and inflammation, with emphasis on the particular diseases studied in this body of work. Chapter 2 focuses on a review of noncanonical NF-KB function and components, as well as its applications in inflammatory bowel disease (IBD), a quintessential example of disruption of intestinal homeostasis. In Chapter 3 we determine the role of noncanonical NF-KB in allergic disease of the upper gastrointestinal tract, namely a novel model of the disease eosinophilic esophagitis. Our studies revealed that loss of NF-KB-inducing kinase (NIK), the bottleneck molecule in noncanonical NF-KB signaling, results in targeted esophageal inflammation, remodeling, and gene expression changes that are comparable to the human disease. In Chapter 4, we examine the role of noncanonical NF-KB in inflammatory bowel disease using biopsy samples from human IBD patients, and compare the expression of various components of the pathway to inflammation status and treatment response. Noncanonical NF-KB is upregulated in IBD patients, and also appears to be specifically upregulated in patients that have lost response to anti-TNF inhibitors, which are potent drugs that are widely used to treat IBD. In Chapter 5 we focus on NIK and its effects on stem cell function, growth, and inflammation-induced cancer in the gut. Loss of NIK in mice results in alterations in colonic stem cell function and changes in colonic microbiome, which predisposes them to the development of inflammation-induced carcinogenesis. Indeed, in human patients with colorectal cancer, noncanonical NF-KB is also suppressed. Overall, we have discovered multiple novel roles of noncanonical NF-KB signaling at multiple levels in the gut and in the context of a variety of diseases, and have greatly expanded the current body of knowledge as to the functions and effects of this pathway.Ph. D.
The gastrointestinal system has a complex set of checks and balances to maintain overall health. If factors involved in the promotion or suppression of inflammation, the regulation of growth, or the prevention of tumor formation become dysregulated, there can be catastrophic consequences for the human body. The aim of this work is to investigate a pathway called noncanonical NF-κB in the development of various diseases in the GI tract. Noncanonical NF-κB is not a well understood pathway and to date has mostly been studied in the context of white blood cell development. However, we discovered that noncanonical NF-κB has several very important functions in the GI tract that have implications in conditions such as inflammatory bowel disease and colorectal cancer. First we explored the role of noncanonical NF-κB in the upper GI tract, namely the esophagus, and found that this signaling pathway is critically involved in the movement of white blood cells called eosinophils to the esophagus, resulting in throat inflammation in both mouse models and human patients. Secondly, we determined that this same pathway also has effects in the lower GI tract. Human patients with inflammatory bowel disease, especially those who develop resistance to popular medications, see an upregulation of this pathway in their colon tissue. Loss of this pathway in the colons of mice also causes changes in growth of the colonic epithelium, and predisposes them to the formation of colon cancer. Interestingly, in human colon cancer patients, we also see similar changes in expression of genes associated with this pathway. Overall, we have found many new and exciting roles for this underappreciated pathway in the gut.
37
Eden, Kristin. "Noncanonical NF-KB in Gastrointestinal Disease". Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/86127.
Testo completoAbstract (sommario):
Noncanonical NF-KB is an alternative NF-KB pathway that is critically involved in the development and maturation of the adaptive immune system. As such, it has typically been studied in B and T cell biology without application to complex organ systems such as the gut. The following work explores the contribution of noncanonical NF-KB to inflammatory and neoplastic disease in the gastrointestinal (GI) system, as well as the effects of its loss on GI health. Chapter 1 opens with an overview of gastrointestinal homeostasis and inflammation, with emphasis on the particular diseases studied in this body of work. Chapter 2 focuses on a review of noncanonical NF-KB function and components, as well as its applications in inflammatory bowel disease (IBD), a quintessential example of disruption of intestinal homeostasis. In Chapter 3 we determine the role of noncanonical NF-KB in allergic disease of the upper gastrointestinal tract, namely a novel model of the disease eosinophilic esophagitis. Our studies revealed that loss of NF-KB-inducing kinase (NIK), the bottleneck molecule in noncanonical NF-KB signaling, results in targeted esophageal inflammation, remodeling, and gene expression changes that are comparable to the human disease. In Chapter 4, we examine the role of noncanonical NF-KB in inflammatory bowel disease using biopsy samples from human IBD patients, and compare the expression of various components of the pathway to inflammation status and treatment response. Noncanonical NF-KB is upregulated in IBD patients, and also appears to be specifically upregulated in patients that have lost response to anti-TNF inhibitors, which are potent drugs that are widely used to treat IBD. In Chapter 5 we focus on NIK and its effects on stem cell function, growth, and inflammation-induced cancer in the gut. Loss of NIK in mice results in alterations in colonic stem cell function and changes in colonic microbiome, which predisposes them to the development of inflammation-induced carcinogenesis. Indeed, in human patients with colorectal cancer, noncanonical NF-KB is also suppressed. Overall, we have discovered multiple novel roles of noncanonical NF-KB signaling at multiple levels in the gut and in the context of a variety of diseases, and have greatly expanded the current body of knowledge as to the functions and effects of this pathway.Ph. D.
The gastrointestinal system has a complex set of checks and balances to maintain overall health. If factors involved in the promotion or suppression of inflammation, the regulation of growth, or the prevention of tumor formation become dysregulated, there can be catastrophic consequences for the human body. The aim of this work is to investigate a pathway called noncanonical NF-κB in the development of various diseases in the GI tract. Noncanonical NF-κB is not a well understood pathway and to date has mostly been studied in the context of white blood cell development. However, we discovered that noncanonical NF-κB has several very important functions in the GI tract that have implications in conditions such as inflammatory bowel disease and colorectal cancer. First we explored the role of noncanonical NF-κB in the upper GI tract, namely the esophagus, and found that this signaling pathway is critically involved in the movement of white blood cells called eosinophils to the esophagus, resulting in throat inflammation in both mouse models and human patients. Secondly, we determined that this same pathway also has effects in the lower GI tract. Human patients with inflammatory bowel disease, especially those who develop resistance to popular medications, see an upregulation of this pathway in their colon tissue. Loss of this pathway in the colons of mice also causes changes in growth of the colonic epithelium, and predisposes them to the formation of colon cancer. Interestingly, in human colon cancer patients, we also see similar changes in expression of genes associated with this pathway. Overall, we have found many new and exciting roles for this underappreciated pathway in the gut.
38
Madden, Lisa J. "Pica and peptides : assessing gastrointestinal malaise /". Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/10637.
Testo completo
39
Spear, Estelle Trego. "Altered Gastrointestinal Motility in Multiple Sclerosis". ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/837.
Testo completoAbstract (sommario):
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.
40
Carvallo, Michelena Alvaro, e Domínguez Jorge Luis Rojas. "Factores asociados a mal pronóstico en pacientes con sangrado digestivo bajo en un hospital público". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2016. http://hdl.handle.net/10757/621792.
Testo completoAbstract (sommario):
Introducción: El sangrado digestivo bajo (SDB) es una entidad cuyas tasas de complicaciones y mortalidad se han incrementado en las últimas décadas. Si bien se han identificado algunos factores relacionados a mal pronóstico, aún quedan variables por evaluar. Objetivo: Identificar factores de mal pronóstico en pacientes que presentaron SDB en el Hospital Nacional Edgardo Rebagliati Martins de Lima, Perú. Materiales y métodos: Se realizó un estudio observacional analítico de tipo cohorte retrospectivo. Se realizó un censo de todos los pacientes que presentaron SDB agudo entre Enero 2010 y Diciembre 2013. Las variables principales a evaluar fueron frecuencia cardiaca ≥ 100/min, presión arterial sistólica < 100 mmHg y hematocrito bajo (≤ 35%) al ingreso. Se definió mal pronóstico como cualquiera de los siguientes criterios: muerte durante la hospitalización, sangrado que requiera transfusión de ≥ 4 unidades de sangre, reingreso dentro del primer mes, o necesidad de cirugía de hemostasia. Resultados: Se incluyó un total de 341 pacientes con SDB, de los cuales el 27% tuvo mal pronóstico y 2% fallecieron. Se encontró como variables asociadas a mal pronóstico: frecuencia cardiaca ≥ 100/min al ingreso (RR: 1,75 IC 95% 1,23-2,50), presión arterial sistólica < 100 mmHg al ingreso (RR: 2,18 IC 95% 1,49-3,19), hematocrito ≤ 35% al ingreso (RR: 1,98 IC 95% 1,23-3,18) y sangrado de origen no determinado (RR: 2,74 IC 95% 1,73-4,36). Conclusiones: Frecuencia cardiaca elevada al ingreso, hipotensión sistólica al ingreso, hematocrito bajo al ingreso y presentar un sangrado en el cual no se encuentra el punto de origen son factores que incrementan el riesgo de presentar mal pronóstico, por lo que se recomienda un monitoreo más estricto en estos pacientes.Background: Lower gastrointestinal bleeding (LGIB) is an event that has shown an increase in complications and mortality rates in the last decades. Although some factors associated with poor outcome have been identified, there are several yet to be evaluated. Objective: To identify risk factors for poor outcome in patients with LGIB in the Hospital Nacional Edgardo Rebagliati Martins of Lima, Peru. Material and methods: A prospective analytic observational cohort study was made, and a census was conducted with all patients with acute LGIB between January 2010 and December 2013. The main variables were heart rate ≥ 100/min, systolic blood pressure < 100 mmHg and low hematocrit (≤ 35%) at admission. Poor outcome was defined as any of the following: death during hospital stay, bleeding requiring transfusion of ≥ 4 blood packs, readmission within one month of hospital discharge, or the need for hemostatic surgery. Results: A total of 341 patients with LGIB were included, of which 27% developed poor outcome and 2% died. Variables found to be statistically related to poor outcome were: heart rate ≥ 100/min at admission (RR: 1,75 IC 95% 1,23-2,50), systolic blood pressure < 100 mmHg at admission (RR: 2,18 IC 95% 1,49-3,19), hematocrit ≤ 35% at admission (RR: 1,98 IC 95% 1,23-3,18) and LGIB of unknown origin (RR: 2,74 IC 95% 1,73-4,36). Conclusions: Elevated heart rate at admission, systolic hypotension at admission, low hematocrit at admission and having a LGIB of unknown origin are factors that increase the risk of developing poor outcome, and these patients should be monitored closely due to their higher risk of complications.
41
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.
Testo completoAbstract (sommario):
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.
42
Dinis, João Vitor Barrau Mendes Ferreira. "Estratégias nutricionais na prevenção de doenças digestivas dos suínos". Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2010. http://hdl.handle.net/10400.5/2573.
Testo completoAbstract (sommario):
Dissertação de Mestrado Integrado em Medicina VeterináriaDepois da proibição do uso de promotores de crescimento em produção animal pela União Europeia em 2003, a suinicultura deparou-se com uma série de doenças que anteriormente estavam suprimidas, nomeadamente a nível do tracto gastrointestinal, devido à incorporação consecutiva de promotores de crescimento, ou seja, antibióticos nos alimentos compostos. Os actuais sistemas de produção de suínos têm um impacto importante nas funções, na integridade e na saúde do seu tubo digestivo, havendo uma diversidade de factores que a podem prejudicar, nomeadamente nutricionais. O uso de determinadas estratégias, tanto a nível das características do alimento como a nível do sistema de alimentação das explorações, permitem diminuir ou até mesmo prevenir o impacto das doenças mais importantes do tubo digestivo dos suínos. A microbiota intestinal desempenha um papel fulcral na sua protecção e na função digestiva e de absorção, estando a constituição das populações microbianas da microflora gastrointestinal dependentes das características do alimento e da incorporação de aditivos que, geralmente, têm como objectivo modular estas populações. Os transtornos gastrointestinais também podem ser prevenidos através da forma como os animais são alimentados, estando a alimentação líquida aplicada em produção intensiva de suínos a mostrar resultados promissores. A finalidade deste trabalho é conhecer de que forma é possível, através da alimentação dos suínos, diminuir ou prevenir o impacto das doenças gastrointestinais mais importantes em suinicultura. Também foi realizado uma análise descritiva de dados recolhidos resultantes de uma prova comercial de rações, numa exploração de suínos clássico, e de dados anuais de uma exploração de suínos ibéricos, alimentados com sistema de alimentação líquida. Em ambos os casos, os dados sugerem um impacto da nutrição na saúde do tracto gastrointestinal dos suínos, assim como nas suas performances produtivas. Em relação à fase de recria, os leitões da exploração de suínos clássicos demonstraram superioridade produtiva em relação aos leitões da exploração de suínos ibéricos.
ABSTRACT - Nutritional strategies in the prevention of pig pig´s digestive disease - Since the use of antibiotics as growth promoters by the European Union was abolished in 2003, pig production faced several constrains related to diseases, mainly at the gastrointestinal level, which were suppressed by the consecutive incorporation of antibiotics in feed. There are a diversity of factors in the actual pig production systems, namely nutritional, that have an important impact in the function and health integrity of the pig digestive tract. The use of specific strategies concerning the characteristics of the diet and the feeding system used at the farm, allow to diminish or even prevent the impact of the most important pig’s digestive tract disorders. The intestinal microbiota seems to play a crucial role in the gastrointestinal function and protection, while the population of bacteria of the microbiota depend of the characteristics of the feed, and the presence of additives that generally have a modulatory effect on microbial growth. The way the animals are fed, and particularly Liquid Feed applied to intensive pig production, is showing promising results in preventing gastrointestinal disorders. The aim of this work is to understand how, through pig diet´s, is possible to decrease or prevent the impact of the most important pig’s gastrointestinal diseases. Based in data collected at a comercial feed trial in a classical pig farm, and from annual data collected at an iberian pig farm, whith a liquid feeding system, a descriptive analysis was made. In both cases, the analysis suggest an impact of nutrition in the pig´s gastrointestinal health, as well as in their productive performances. As for the growing phase, the piglets from the classical pig farm revealed productive superiority to the piglets from the iberian pig farm.
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Martínez, Perea Vicente. "Función de CCK y de los lípidos en la regulación de la motilidad gastrointestinal en el pollo". Doctoral thesis, Universitat Autònoma de Barcelona, 1993. http://hdl.handle.net/10803/3827.
Testo completo
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Cassana, Abad Carla Alessandra, Silvia Scialom, Eddy R. Segura e Alfonso Chacaltana. "Estudio de validación diagnóstica de la escala de Glasgow-Blatchford para la predicción de mortalidad en pacientes con hemorragia digestiva alta en un hospital de Lima, Perú (junio 2012-diciembre 2013)". Sociedad Española de Patología Digestiva, 2015. http://hdl.handle.net/10757/608517.
Testo completoAbstract (sommario):
Antecedentes y propósito del estudio: la hemorragia digestiva alta es una causa importante de ingreso hospitalario y constituye la principal emergencia gastroenterológica, con una tasa de mortalidad de hasta el 14%. En el Perú no existen estudios sobre el uso de la escala de Glasgow-Blatchford para predecir mortalidad por hemorragia digestiva alta. El objetivo de este estudio es realizar la validación externa de la escala de Glasgow-Blatchford y establecer su mejor punto de corte para predecir mortalidad por hemorragia digestiva alta en un hospital de Lima, Perú.
Métodos: estudio de validación diagnóstica, analítico, longitudinal, de tipo retrospectivo, con datos de pacientes con diagnóstico clínico y endoscópico de hemorragia digestiva alta atendidos en la Unidad de Hemorragia Digestiva del Hospital Nacional Edgardo Rebagliati Martins, entre junio de 2012 y diciembre de 2013. Calculamos el área bajo la curva ROC (receiver operating characteristic) de la escala de Glasgow-Blatchford para predecir mortalidad, con un intervalo de confianza al 95%.
Resultados: un total de 339 registros fueron analizados. El 57,5% fueron varones y la edad media (desviación estándar) fue de 67,0 (15,7) años. La mediana de la escala de Glasgow-Blatchford obtenida en la población fue de 12. El análisis ROC para mortalidad dio un área bajo la curva de 0,59 (IC95% 0,5-0,7). Se estratificó por tipo de hemorragia digestiva alta, obteniendo un área bajo la curva de 0,66 (IC95% 0,53-0,78) para el tipo no variceal.
Conclusiones: en la población estudiada, la escala de Glasgow-Blatchford no posee una validez diagnóstica adecuada para predecir mortalidad.
45
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.
Testo completoAbstract (sommario):
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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Lopes, Marco A. F. "Hydration of Colonic Ingesta and Feces in Horses Fed Large Grain Meals or Treated with Enteral Fluid Therapy, Saline Cathartics and Intravenous Fluid Therapy". Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/29338.
Testo completoAbstract (sommario):
Systemic hydration, plasma electrolytes, ingesta and fecal hydration and gastrointestinal passage of cobalt (after CoEDTA administration via nasogastric tube) in horses fed large grain meals or treated with enteral fluid therapy, IV fluid therapy and enteral laxatives were investigated. In the first study, 0.9% NaCl (10 L/h/8h) was administered slowly via a small-bore nasogastric tube or as 10 L boluses via a large-bore nasogastric tube to four normal horses. In the other studies, horses with a right dorsal colon fistula were used. To create the right dorsal colon fistula, a cannula with 5 cm internal diameter was implanted 2 to 6 weeks after a right dorsal colopexy had been created. Six horses with the right dorsal colostomy were alternately used to test three feeding regimes for 48 h: 1- hay free choice; 2- hay free choice plus 4.5 kg of sweet feed twice daily after a period of 5 days of adaptation; 3- sudden change from hay to hay plus sweet feed. Seven horses with the right dorsal colostomy were alternately used to test 6 experimental conditions while fasted for 24 h: 1- control (no treatment), 2- enteral MgSO4 (1 g/kg), 3- enteral Na2SO4 (1 g/kg), 4- IV lactated Ringer's solution (5 L/h/12 h), 5- enteral water (5 L/h/12 h), 6- enteral electrolyte solution (5 L/h/12 h). In the last study, four horses with the right dorsal colostomy were alternately treated with enteral electrolyte solution (10 L/h/6h) and enteral MgSO4 (1 g/kg) plus IV fluid therapy (10 L/h/6h). Despite the administration regimen, enteral administration of 0.9% NaCl produced diarrhea, hypernatremia and hyperchloremia. Colostomy allowed serial collection of large ingesta samples. Grain ingestion did not change PCV or plasma protein, but affected plasma electrolytes and produced dehydration of ingesta and formation of frothy ingesta. Fasting delayed gastrointestinal transit. Enteral fluid therapy was the most effective treatment in promoting ingesta hydration. Enteral water, MgSO4, Na2SO4, IV fluid therapy and enteral MgSO4 plus IV fluid therapy were either ineffective in promoting ingesta hydration or produced marked plasma electrolyte imbalance. These findings support the use of enteral fluid therapy in horses with gastrointestinal impaction.Ph. D.
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Dahlhoff, Maik. "Actions of betacellulin in the gastrointestinal tract". Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-98465.
Testo completo
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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.
Testo completoAbstract (sommario):
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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Hedberg, Jakob. "Gastrointestinal Physiology and Results following Bariatric Surgery". Doctoral thesis, Uppsala universitet, Gastrointestinalkirurgi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-131889.
Testo completoAbstract (sommario):
The number of operations for morbid obesity is rising fast. We have examined aspects of postoperative physiology and results after bariatric surgery. The pH in the proximal pouch after Roux-en-Y gastric bypass (RYGBP) was investigated with catheter-based and wire-less technique. Gastric emptying, PYY-levels in the fasting state and after a standardized meal was evaluated after biliopancreatic diversion with duodenal switch (DS). A clinical trial was undertaken, comparing DS to RYGBP in patients with BMI>48. Main outcome variables were safety and long-term weight results as well as abdominal symptoms and laboratory results. Patients with stomal ulcer had significantly lower pH in their proximal gastric pouch as compared to asymptomatic control subjects. Long-time pH measurements with the wire-less BRAVO-system were feasible and demonstrated pH<4 in median 10.5% of the time in asymptomatic post-RYGBP patients. After DS, the T50 of gastric emptying was 28±16 minutes. PYY-levels were higher after DS than in age-matched control subjects. BMI-reduction was greater after DS (24 BMI-units) than after RYGBP (17 BMI-units) in median 3.5 (2.0-5.3) years after surgery (p<0.001). Fasting glucose and HbA1c levels were lower one and three years after DS as compared to RYGBP. On the other hand, DS-patients reported having more diarrhea and malodorous flatus. This thesis has resulted in deepened knowledge. Acid produced in the proximal pouch is an important pathogenetic factor in the development of stomal ulcer after RYGBP. However, symptom-free patients have an acidic environment in the proximal Roux-limb as well. After DS, gastric emptying is fast, but not instantaneous, and PYY-levels are high. DS results in superior weight reduction and better glucose control as compared to RYGBP in patients with BMI>48. We believe that DS has a place in surgical treatment of the super-obese, even though symptoms of diarrhea and malodorous flatus are more common after DS.