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Gut Function (gut + function)
Selected AbstractsFundus rotation gastroplasty: rationale, technique and results,DISEASES OF THE ESOPHAGUS, Issue 2 2002W. Uhl SUMMARY. Anastomotic leakage is the main factor (up to 30%) for postoperative morbidity and mortality after esophageal resection. Compromised anastomotic perfusion after dissection of supplying vessels for gastric tube formation and tension on the suture line are the two main reasons for anastomotic insufficiency. To prevent anastomotic leakage, a new technique for gastric tube formation after esophageal resection has been developed and introduced into surgical practice: the fundus rotation gastroplasty (FRG). The following paper summarizes rationale, technique and early results of this new technique. It is shown that the FRG is a safe and effective technique for esophageal reconstruction and offers important advantages over conventional gastroplasties: (i) the improved perfusion of the oral part of the tube; (ii) the gain of tube length allowing for a safer performance of even pharyngeal anastomosis as shown by the low insufficiency rate of 9%; and (iii) the increase of remaining gastric reservoir supporting physiologic stomach and gut function. Therefore, the FRG seems to be an alternative and safe method for esophageal reconstruction, especially for high anastomotic locations. [source] In vivo analysis of gut function and disease changes in a zebrafish larvae model of inflammatory bowel disease: A feasibility studyINFLAMMATORY BOWEL DISEASES, Issue 7 2010Angeleen Fleming PhD Abstract Background: The aim of this study was to develop a model of inflammatory bowel disease (IBD) in zebrafish larvae, together with a method for the rapid assessment of gut morphology and function in vivo thereby enabling medium-throughput compound screening. Methods: Assays were performed using larval zebrafish from 3,8 days postfertilization (d.p.f.) in 96-well plates. Gut morphology and peristalsis were observed in vivo using fluorescent imaging following ingestion of fluorescent dyes. IBD was induced by addition of 2,4,6-trinitrobenzenesulfonic acid (TNBS) to the medium within the well. Pathology was assessed in vivo using fluorescent imaging and postmortem by histology, immunohistochemistry, and electron microscopy. Therapeutic compounds were evaluated by coadministration with TNBS. Results: A novel method of investigating gut architecture and peristalsis was devised using fluorescent imaging of live zebrafish larvae. Archetypal changes in gut architecture consistent with colitis were observed throughout the gut. Significant changes in goblet cell number and tumor necrosis factor alpha (TNF-,) antibody staining were used to quantify disease severity and rescue. Prednisolone and 5-amino salicylic acid treatment ameliorated the disease changes. Candidate therapeutic compounds (NOS inhibitors, thalidomide, and parthenolide) were assessed and a dissociation was observed between efficacy assessed using a single biochemical measure (TNF-, staining) versus an assessment of the entire disease state. Conclusions: Gut physiology and pathology relevant to human disease state can be rapidly modeled in zebrafish larvae. The model is suitable for medium-throughput chemical screens and is amenable to genetic manipulation, hence offers a powerful novel premammalian adjunct to the study of gastrointestinal disease. (Inflamm Bowel Dis 2010) [source] Simultaneous measurement of serotonin and melatonin from the intestine of old mice: the effects of daily melatonin supplementationJOURNAL OF PINEAL RESEARCH, Issue 1 2010P. P. Bertrand Abstract:, Ageing is associated with important changes in gastrointestinal function and in the levels of intestinal hormones secreted. Enterochromaffin (EC) cells containing serotonin (5-HT) and melatonin may play a major role in maintaining gut function during ageing. Our aim was to characterise the mucosal availability of 5-HT and melatonin in the ileum and colon of a mouse model of ageing. Female young mice (2,5 month; n = 6), aged mice (22,24 months; n = 6) and aged mice treated with melatonin (n = 6; 10 mg/kg/day) were examined. Electrochemical methods were used to measure 5-HT and melatonin concentrations near the mucosal surface of ileum and distal colon. Amperometry studies showed that steady state levels of 5-HT from ileum and colon were decreased in aged mice treated with melatonin when compared to aged mice, while compression-evoked 5-HT release was unchanged. Differential pulse voltammetry studies showed that young mice had concentrations of 5-HT of 4.8 ± 0.8 ,m in the ileum and 4.9 ± 1.0 ,m in the colon. Concentrations of melatonin were 5.7 ± 1.4 ,m in the ileum and 5.6 ± 1.9 ,m in the colon. Compared to young mice, the levels of 5-HT and melatonin were increased in aged mice (combined ileum and colon: 5-HT = 130% and melatonin = 126% of young mice) and decreased in melatonin-treated mice (5-HT = 94% and melatonin = 82%). In conclusion, our data show that the availability of gut 5-HT and melatonin is increased in aged mice and melatonin treatment suppresses natural gastrointestinal production of 5-HT and melatonin in the aged mouse intestine. [source] Altered intestinal microbiota in irritable bowel syndromeNEUROGASTROENTEROLOGY & MOTILITY, Issue 5 2010K. J. Lee Abstract, Recent studies have suggested that alterations in the composition of the intestinal microbiota may play an important role in irritable bowel syndrome (IBS) symptoms. However, an association between the composition of the intestinal microbiota and IBS symptoms has not been clearly demonstrated. In the current issue of the Journal, Tana et al. suggest that altered intestinal microbiota contributes to the symptoms of IBS through increased levels of organic acids. In fecal samples, IBS patients had significantly higher numbers of Veillonella and Lactobacillus than healthy controls. They also showed significantly higher levels of acetic acid and propionic acid. Furthermore, IBS patients with high acetic acid or propionic acid levels presented more severe symptoms, impaired quality of life and negative emotions. These results are in accordance with the concept that the gut microbiota influences the sensory, motor and immune system of the gut and interacts with higher brain centers. Small intestinal bacterial overgrowth observed in a subset of IBS patients describes quantitative changes in the small intestinal microbiota. Data on qualitative changes in the gut microbiota in IBS patients are lacking. Different members of gut bacteria may have different influence on gut function. The concepts identified here may lead to the development of novel therapeutic strategies for IBS using manipulation of the intestinal microbiota. [source] Understanding the role of tryptophan and serotonin metabolism in gastrointestinal functionNEUROGASTROENTEROLOGY & MOTILITY, Issue 12 2009D. Keszthelyi Abstract, Tryptophan is the precursor of a wide array of metabolites, which are involved in a variety of aspects of human nutrition and metabolism. Accumulating evidence suggests a role of tryptophan metabolites, especially serotonin (5-hydroxytryptamin) in intestinal (patho) physiology, although mechanisms of action are still poorly understood. Alterations of serotonin metabolism may give rise to gastrointestinal dysfunction. Recently, it has been postulated that other metabolites of tryptophan, mostly of the kynurenine pathway, also play a role in regulating gut function. This review analyses the current knowledge of the interrelationship between tryptophan metabolic pathways and summarizes the existing scientific evidence regarding the role of tryptophan metabolites in intestinal function and in the pathogenesis of gastrointestinal diseases. [source] Important antinutrients in plant feedstuffs for aquaculture: an update on recent findings regarding responses in salmonidsAQUACULTURE RESEARCH, Issue 3 2010Ĺshild Krogdahl Abstract This review presents an overview of antinutritive factors (ANFs) relevant for fish nutrition. The sources of ANFs and the possibilities of reducing the impact of ANFs are briefly mentioned. Proteinase inhibitors, lectins, saponins and oligosaccharides are given a more thorough presentation regarding mechanisms of action and the state of knowledge regarding effects on gut function in fish and upper safe dietary levels. Thereafter, selected results from recent works addressing the involvement of T cells and proteinase-activated receptors in soybean-induced enteritis are summarized. Our conclusions are as follows: we are only beginning to understand effects of ANFs in fish; strengthening of the knowledge base is urgently needed to understand the effects and to find the means to overcome or modify these effects; interactions between the effects of ANFs appear to be very important; the microbiota may modify the effects of ANFs; not only salmonids are affected; not only soybeans contain ANFs of biological importance in fish; and with increased knowledge, we can develop better diets for optimal nutrition, health and economy in aquaculture. [source] Consequences of Citrobacter rodentium infection on enteroendocrine cells and the enteric nervous system in the mouse colonCELLULAR MICROBIOLOGY, Issue 4 2006Jennifer R. O'Hara Summary We tested the hypothesis that Citrobacter rodentium infection leads to changes in the mucosal enteroendocrine signalling and the enteric nervous system and that the host's immune response contributes to these changes. Enteroendocrine cells, serotonin (5-HT) reuptake transporter (SERT), 5-HT release, and inducible nitric oxide synthase (iNOS) expression were assessed in the colon of infected wild-type or severe combined immunodeficient (SCID) mice. Immunoreactivity for iNOS and neuropeptides were examined in the submucosal and myenteric plexuses. Mice were orogastrically infected with C. rodentium and experiments were conducted during the injury phase (10 days) and the recovery phase (30 days). 5-HT and somatostatin enteroendocrine cells and SERT were significantly reduced 10 days after infection, with numbers returning to control values at 30 days. 5-HT release was increased at 10 days. Changes to the mucosal serotonin signalling system were not observed in SCID mice. iNOS immunoreactivity was increased in the submucosa and mucosa at 10 days and returned to baseline levels by 30 days. No differences were observed in neuropeptide or iNOS immunoreactivity in the enteric plexuses following infection. The host's immune response underlies changes to enteroendocrine cells, SERT expression and 5-HT release in C. rodentium infection. These changes could contribute to disturbances in gut function arising from enteric infection. [source] Protease-activated receptor-4 (PAR4): a role as inhibitor of visceral pain and hypersensitivityNEUROGASTROENTEROLOGY & MOTILITY, Issue 11 2009C. Augé Abstract, Protease-activated receptor-4 (PAR4) belongs to the family of receptors activated by the proteolytic cleavage of their extracellular N-terminal domain and the subsequent binding of the newly released N-terminus. While largely expressed in the colon, the role of PAR4 in gut functions has not been defined. We have investigated the effects of PAR4 agonist on colonic sensations and sensory neuron signalling, and its role in visceral pain. We observed that a single administration of the PAR4 agonist peptide (AYPGKF-NH2), but not the control peptide (YAPGKF-NH2) into the colon lumen of mice significantly reduced the visceromotor response to colorectal distension at different pressures of distension. Further, intracolonic administration of the PAR4 agonist, but not the control peptide, was able to significantly inhibit PAR2 agonist- and transcient receptor potential vanilloid-4 (TRPV4) agonist-induced allodynia and hyperalgesia in response to colorectal distension. Protease-activated receptor-4 was detected in sensory neurons projecting from the colon, and isolated from the dorsal root ganglia, where it co-expressed with PAR2 and TRPV4. In total sensory neurons, PAR4 agonist exposure inhibited free intracellular calcium mobilization induced by the pro-nociceptive agonists of PAR2 and TRPV4. Finally, PAR4 -deficient mice experienced increased pain behaviour in response to intracolonic administration of mustard oil, compared with wild-type littermates. These results show that PAR4 agonists modulate colonic nociceptive response, inhibit colonic hypersensitivity and primary afferent responses to pro-nociceptive mediators. Endogenous activation of PAR4 also plays a major role in controlling visceral pain. These results identify PAR4 as a previously unknown modulator of visceral nociception. [source] | |||||||||||||