Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acute gut disorder is a cause for significant medicinal and economic concern. Certain individual pathogens of the gut, often transmitted in food or water, have the ability to cause severe discomfort. There is a need to manage such conditions more effectively. The route of reducing the risk of intestinal infections through diet remains largely unexplored. Antibiotics are effective at inhibiting pathogens; however, these should not be prescribed in the absence of disease and therefore cannot be used prophylactically. Moreover, their indiscriminate use has reduced effectiveness. Evidence has accumulated to suggest that some of the health-promoting bacteria in the gut (probiotics) can elicit a multiplicity of inhibitory effects against pathogens. Hence, an increase in their numbers should prove effective at repressing pathogen colonisation if/when infectious agents enter the gut. As such, fortification of indigenous bifidobacteria/lactobacilli by using prebiotics should improve protection. There are a number of potential mechanisms for lactic acid bacteria to reduce intestinal infections. Firstly, metabolic endproducts such as acids excreted by these micro-organisms may lower the gut pH to levels below those at which pathogens are able to effectively compete. Also, many lactobacilli and bifidobacteria species are able to excrete natural antibiotics, which can have a broad spectrum of activity. Other mechanisms include an improved immune stimulation, competition for nutrients and blocking of pathogen adhesion sites in the gut. Many intestinal pathogens like type 1 fimbriated Escherichia coli, salmonellae and campylobacters utilise oligosaccharide receptor sites in the gut. Once established, they can then cause gastroenteritis through invasive and/or toxin forming properties. One extrapolation of the prebiotic concept is to simulate such receptor sites in the gut lumen. Hence, the pathogen is 'decoyed' into not binding at the host mucosal interface. The combined effects of prebiotics upon the lactic acid flora and anti-adhesive strategies may lead towards new dietary interventions against food safety agents.
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PMID:Prebiotics and resistance to gastrointestinal infections. 1587 92

A fusion protein containing the shiga toxin-1 B subunit (STB) linked to a 90 amino acid peptide (aa residues 86--175) from simian rotavirus (SA--11) nonstructural protein NSP4 was synthesized in Escherichia coli. Mice orally inoculated with 60 microg of STB::NSP4(90) fusion protein per dose generated higher humoral and intestinal antibody titers than mice inoculated with 30 microg of NSP4 alone. Serum anti-NSP4 IgG2a isotype titers were substantially greater than IgG1 titers, suggesting a dominant Th1 immune response. ELISA measurement of cytokines secreted from splenocytes isolated from immunized mice confirmed the STB::NSP4(90) fusion protein stimulation of a strong Th1 cell mediated immune response. Diarrhea in SA-11 rotavirus challenged neonates suckling from STB::NSP4 immunized dams was significantly reduced in severity and duration in comparison with virus challenged neonates from unimmunized mice. Together, our experiments demonstrate for the first time that the shiga toxin B subunit provides ligand mediated delivery of virus antigens to the gut-associated lymphoid tissues for enhanced stimulation of humoral and cellular responses against rotavirus gastroenteritis.
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PMID:Oral immunization with a shiga toxin B subunit: rotavirus NSP4(90) fusion protein protects mice against gastroenteritis. 1604 Jan 69

The human gut is known to be a reservoir of a wide variety of microbes, including viruses. Many RNA viruses are known to be associated with gastroenteritis; however, the enteric RNA viral community present in healthy humans has not been described. Here, we present a comparative metagenomic analysis of the RNA viruses found in three fecal samples from two healthy human individuals. For this study, uncultured viruses were concentrated by tangential flow filtration, and viral RNA was extracted and cloned into shotgun viral cDNA libraries for sequencing analysis. The vast majority of the 36,769 viral sequences obtained were similar to plant pathogenic RNA viruses. The most abundant fecal virus in this study was pepper mild mottle virus (PMMV), which was found in high concentrations--up to 10(9) virions per gram of dry weight fecal matter. PMMV was also detected in 12 (66.7%) of 18 fecal samples collected from healthy individuals on two continents, indicating that this plant virus is prevalent in the human population. A number of pepper-based foods tested positive for PMMV, suggesting dietary origins for this virus. Intriguingly, the fecal PMMV was infectious to host plants, suggesting that humans might act as a vehicle for the dissemination of certain plant viruses.
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PMID:RNA viral community in human feces: prevalence of plant pathogenic viruses. 1633 43

This report presents 2 cases in which puppy fatalities were associated with canine coronavirus (CCV), but no evidence of concurrent canine parvovirus (CPV-2) disease was observed. Case 1 involved a 7-week-old, male short-haired Chihuahua, which had become lethargic 24 hours after purchase from a pet store. Within 72 hours, the puppy began to vomit, had diarrhea, and was admitted to the veterinary clinic, where it was placed on IV fluids. The parvovirus Cite test was negative. The puppy died within 12 hours of admission and was submitted for diagnostic workup. Gross pathology revealed an enteritis suggestive of CPV-2. Histopathology on intestines showed scattered dilated crypts with necrotic cellular debris and neutrophils. There was moderate depletion and necrosis of lymphoid follicles. Electron microscopy (EM) on intestinal contents was positive for coronavirus and negative for parvovirus. Immunohistochemistry (IHC) on gut sections was positive for CCV and negative for CPV-2. Case 2 was an 8-week-old, male Shih Tzu, which was admitted to the veterinary clinic exhibiting symptoms of severe gastroenteritis with abdominal pain. The referring veterinarian euthanized the puppy, and the entire body was submitted for diagnostic evaluation. Necropsy revealed a severe ileo-cecal intussusception and segmental necrotic enteritis of the small intestine. Electron microscopy of the intestinal contents was positive for coronavirus and negative for parvovirus. Immunohistochemistry on sections of affected gut were positive for CCV and negative for CPV-2. These cases emphasize the importance of pursuing a diagnosis of CCV in young puppies when CPV-2 disease has been ruled out by IHC.
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PMID:Canine coronavirus-associated puppy mortality without evidence of concurrent canine parvovirus infection. 1647 26

Irritable bowel syndrome (IBS) is one of the most common disorders and a heterogeneous condition in view of symptoms and underlying mechanisms. Though underlying causes of pathophysiologic changes remain unclear, low grade mucosal inflammation and abnormal intestinal motility are accepted mechanisms which alter gut function and generate symptoms of IBS. First, before 1980s, abnormal colonic and rectal motor functions were regarded as the main pathophysiology of IBS, but only 25-75% of IBS patients have apparent motor abnormalities which differ from the motor functions in normal controls. So, various gastrointestinal motility tests were not indicated for the diagnosis of IBS. The high-amplitude propagating contractions of colon in IBS patients may be related to the visceral pain perception. Second, the low grade mucosal inflammation may be involved in the pathophysiology of visceral hypersensitivity. Post infectious IBS (PI-IBS) occupied 6-17% of the total IBS and some previous prospective studies reported that 7-33% of acute bacterial enteritis patients developed IBS after 6-12 months of infection. The relative risk of IBS in the gastroenteritis cohort was 11.9 and the strongest risk factor is the duration of diarrhea. After enteritis event, the increased number of immunocytes, mast cells and large amount of lymphocytes infiltration were revealed in mucosa and enteric nervous system of the gut. Beside the inflammatory cells, enterochromaffin cells, cytokines and inducible nitric oxide may be related to the pathophysiologic mechanism of PI-IBS. Lastly, the abnormalities in the gastrointestinal autonomic nervous system can induce constipation or motor disorders, but further research should elucidate it.
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PMID:[The pathophysiology of irritable bowel syndrome: inflammation and motor disorder]. 1649 75

Salmonella enterica serovar Enteritidis has emerged during the last 20 years as the major causative agent of food-borne gastroenteritis in humans and as the major infectious agent on poultry farms, replacing Salmonella enterica serovar Typhimurium as the dominant pathogenic serovar. Because adhesion to gut tissues and colonization of the alimentary tract, mediated in large part by the FimH adhesins located on type 1 fimbriae, is an important stage in the pathogenesis of both serovars, the binding properties of the FimH adhesins from these two enteropathogens were compared. Salmonella Enteritidis FimH protein and the Salmonella Typhimurium low-adhesive variant of this adhesin were expressed in Escherichia coli and the recombinant proteins were analysed for their ability to bind glycoproteins carrying different oligomannosidic structures and different types of eukaryotic cells. In static binding assays (ELISA and Western blotting) both FimH proteins bound equally well to all three tested glycoproteins (RNase B, horseradish peroxidase and mannan-BSA). In addition, no differences were found in the binding specificity of the FimH proteins and intact cells of Salmonella Enteritidis and Salmonella Typhimurium to human colon carcinoma or bladder cancer cells. The presence of the same amino acid residues at positions 61 (glycine) and 118 (phenylalanine) and the similar binding properties of these two adhesins suggest that the newly described FimH protein of Salmonella Enteritidis represents the low-adhesive variant found in Salmonella Typhimurium. To study the binding specificity of Salmonella Enteritidis FimH protein further, direct kinetic analysis using surface plasmon resonance was performed. With this method it was found that Salmonella Enteritidis FimH adhesin bound with the highest K(d) value to high-mannose type N-glycans carried by RNase B; about 100 times lower K(d) values were obtained in the interactions with mannan-BSA and horseradish peroxidase.
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PMID:Functional characterization of the FimH adhesin from Salmonella enterica serovar Enteritidis. 1662 51

The intestinal immune and inflammatory responses of Norovirus (NoV) are poorly defined. The objective of this study was to investigate fecal cytokine and lactoferrin profiles in response to NoV gastroenteritis in travelers. Both fecal cytokines and fecal lactoferrin were measured for NoV-associated diarrhea (N = 7), mixed infection of NoV and enterotoxigenic E. coli (ETEC)-associated diarrhea (N = 10) and in pathogen-negative diarrhea cases (N = 19). Both IL-2 and IFN-gamma were significantly increased in NoV-associated diarrhea specimens, suggesting a predominant Th1 immune response to NoV infection in the gut. When a mixed infection of NoV and ETEC occurred, a combined Th1/Th2 response was observed suggesting a dual immune response secondary to infection by both pathogens. Intestinal inflammation associated with increased fecal lactoferrin, important in bacterial enteric infection, was not found in NoV-associated gastroenteritis.
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PMID:Fecal cytokines and markers of intestinal inflammation in international travelers with diarrhea due to Noroviruses. 1662 72

About twenty years ago, a new coronavirus, porcine respiratory coronavirus (PRCoV), was detected in swine herds. This virus is related to transmissible gastroenteritis virus (TGEV); however, it is not enteropathogenic but causes only minor respiratory symptoms. As PRCoV shares some epitopes for neutralizing antibodies with TGEV, it acts like a nature-made vaccine against TGEV resulting in a drastic reduction of TGE outbreaks in Europe. A major difference between the two porcine coronaviruses is a large deletion in the surface protein S gene of PRCoV. Because of this structural difference, TGEV but not PRCoV has a sialic acid binding activity that allows the attachment to mucins and mucin-type glycoproteins. The sialic acid binding activity may allow TGEV to overcome the mucus barrier in the gut and to get access to the intestinal epithelium for initiation of infection.
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PMID:Transmissible gastroenteritis virus infection: a vanishing specter. 1671 52

Irritable bowel syndrome (IBS) is a complex, yet common diagnosis in gastroenterology. Recent data suggest the increasing importance of bacteria in the pathophysiology of IBS. Some studies have shown that IBS can be precipitated by an acute case of gastroenteritis. These pathogenic organisms may contribute to long-term gut dysfunction. In another line of effort, a growing body of evidence links IBS to the presence of excessive bacteria in the small bowel, called bacterial overgrowth. Although the means by which this is determined have been indirect, studies demonstrating the benefit of unabsorbed antibiotics suggest that reduction in gut flora is important. Further work has also examined bacterial overgrowth in the context of the various symptoms of patients with IBS. These symptom complexes include constipation, diarrhea, and alternating forms of the condition. Although this idea seems initially counterintuitive, it has been demonstrated that the fermentation of methane in the gut is associated with and can result in the slowing of intestinal transit, resulting in constipation. In this review, these topics are discussed and outlined.
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PMID:Bacteria and irritable bowel syndrome: the evidence for small intestinal bacterial overgrowth. 1683 42

Lesions associated with two species of tapeworms within the digestive tract of wild-caught specimens of the bull shark, Carcharhinus leucas, and the sicklefin weasel shark, Hemigaleus microstoma, from Malaysian Borneo are described. Portions of the glandular stomach and pyloric gut with parasites were removed and fixed in 10% formalin buffered in sea water. Whole mounts, histological sections of tissues with and without worms in situ, and scanning electron microscopy images of detached worms were examined. Both species of cestodes belonged to the trypanorhynch family Tentaculariidae. Heteronybelinia estigmena was found in large numbers parasitizing the pyloric gut of C. leucas; an unidentified tentaculariid was found in relatively small numbers in both the glandular stomach and pyloric gut of H. microstoma. Both species burrowed their scoleces deeply in the mucosa and attached via hooked tentacles and unciniform microtriches of the scolex. The lesions induced by the parasites were marked in both sharks and ranged from acute necrotizing to chronic granulomatous gastroenteritis. Regenerative hyperplasia and intestinal metaplasia of gastric epithelium were also present. The severity and character of pathology was causally linked to the intensity of infection, the attachment mode of the parasites, and to the anatomophysiological relationships within the gut of the host shark.
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PMID:Mode of attachment and lesions associated with trypanorhynch cestodes in the gastrointestinal tracts of two species of sharks collected from coastal waters of Borneo. 1686 23


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