PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GASTROINTESTINAL TRACT”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources

Inhibition of translocation of viable Escherichia coli from the gastrointestinal tract of mice by bacterial antagonism.

The incidence of translocation of viable Escherichia coli C25 from the gastrointestinal tract to the mesenteric lymph nodes was compared in gnotobiotic mice colonized with only E. coli C25 and in gnotobiotic mice colonized with E. coli C25 plus the whole cecal flora from specific pathogen-free mice. The population levels of E. coli C25 in the ilea and ceca of these mice also were compared. E. coli C25 maintained high population levels in the gastrointestinal tracts of the monoassociated gnotobiotes, and the incidence of translocation to the mesenteric lymph nodes was 100%. The gastrointestinal population levels of E. coli C25 were reduced drastically in the gnotobiotes associated with both E. coli C25 and a cecal flora with concomitant reduction in the incidence of translocation of E. coli C25 from 100 to 0%. A decrease in the numbers of viable E. coli C25 per mesenteric lymph node also accompanied the decrease in C. coli C25 population levels in the gastrointestinal tracts of these mice. Thus, high population levels of E. coli C25 in the gastrointestinal tracts of monoassociated gnotobiotic mice appear to promote translocation of viable E. coli C25 to the mesenteric lymph nodes. Bacterial antagonism of E. coli population levels in conventional mice, therefore, could be one mechanism whereby viable E. coli are confined to the gastrointestinal tract.

Animals↗

Expression of Ca(2+)-activated K(+) channels, SK3, in the interstitial cells of Cajal in the gastrointestinal tract.

A role for small-conductance Ca(2+)-activated K(+) (SK) channels on spontaneous motility of the gastrointestinal tract has been suggested. Although four subtypes of SK channels were identified in mammalian tissues, the subtypes of SK channel expressed in the gastrointestinal tract are still unknown. In this study, we investigated the expression and localization of SK channels in the gastrointestinal tract. RT-PCR analysis shows expression of SK3 and SK4 mRNA, but not SK1 or SK2 mRNA, in the rat intestine. SK3 immunoreactivity was detected in the myenteric plexus and muscular layers of the stomach, ileum, and colon. SK3-immunoreactive cells were stained with antibody for c-kit, a marker for the interstitial cells of Cajal (ICC), but not with that for glial fibrillary acidic protein in the ileum and stomach. Immunoelectron microscopic analysis indicates that SK3 channels are localized on processes of ICC that are located close to the myenteric plexus between the longitudinal and circular muscle layers and within the muscular layers. Because ICC have been identified as pacemaker cells and are known to play a major role in generating the regular motility of the gastrointestinal tract, these results suggest that SK3 channels, which are expressed specifically in ICC, play an important role in generating a rhythmic pacemaker current in the gastrointestinal tract.

Animals↗

[Interactions between the brain and gastrointestinal tract].

Peptides have been implicated to subserve neurotransmitter function within the brain and the gastrointestinal tract. While the anatomical distribution of neuropeptides suggest that most neuropeptides identified in brain tissue are also present in the gastrointestinal tract and vice versa, the functional interrelationship of the central nervous system and the gastrointestinal tract are less well documented. Most studies examined the peripheral actions of peptide hormones on visceral functions. This paper summarizes the central nervous system actions of neuropeptides on various gastrointestinal entities (secretion, motility, blood flow, absorption and eating behavior). This paper also deliniates the efferent and afferent pathways that allow to occur communication of the brain and the gastrointestinal tract. From this summary it will become evident that over the past ten years progress has mainly been made in the understanding of how the brain regulates gastrointestinal functions and only little knowledge has been accumulated to improve the understanding of afferent information flow from the gut to the brain.

Animals↗

Effect of haemodialysis on upper gastrointestinal tract pathology in patients with chronic renal failure.

Upper gastrointestinal tract pathology observed at autopsy in 94 patients with end-stage renal disease (GFR less than 10 ml/min) was analysed retrospectively. To better evaluate the effect of haemodialysis on this pathology, the chronic renal failure patients were subdivided into three groups: 19 patients who had died before haemodialysis treatment could be undertaken (group I), 21 patients who had died during the first month (group II), and 54 patients who had died after at least one month of haemodialysis treatment (group III). The results revealed that the number of patients with upper gastrointestinal tract pathology was significantly higher in groups I and II (58% and 57% respectively) as compared to group III (31%) and controls (35%). No difference could be demonstrated between group III and controls. The most prevalent lesions observed were gastritis, followed by gastric and peptic ulcers. The incidence of this pathology appeared to decline as the duration of dialysis therapy increased. Mortality caused by upper gastrointestinal tract pathology remained high during the first two years of treatment in group III, despite a smaller incidence of upper tract lesions. This was explained by a relatively higher proportion of haemorrhage.

Cross-Sectional Studies↗

Endoscopic and pathological manifestations of the gastrointestinal tract in familial amyloidotic polyneuropathy type I (Met30).

OBJECTIVES: To evaluate the characteristic changes in the gastrointestinal tract in familial amyloidotic polyneuropathy (FAP) (Met30), both fibre gastroscopy and colonoscopy studies were performed in FAP (Met30) patients. Microscopic changes were also examined in autopsied and biopsied materials from patients with FAP, and compared with data from autopsied samples from patients with AL amyloidosis, and secondary amyloidosis patients. DESIGN: Endoscopic and histopathological study. SETTING: Kumamoto University Hospital, Kumamoto, Japan. SUBJECTS: Nine patients with FAP (Met30) underwent fibre gastroscopy and colonoscopy. Six autopsied and 23 biopsied gastrointestinal samples from FAP patients, four from autopsied amyloidosis (including two myeloma associated form), and two from autopsied secondary amyloidosis patients were examined for histopathological study. MAIN OUTCOME MEASURES: Fibre gastroscopy and colonoscopy were employed for macroscopic study. Congo red and H-E staining were performed for histopathological study. Macroscopic changes in the gastrointestinal tract and microscopic differences in the amyloid distribution pattern were compared between the different types of amyloidosis. RESULTS: Fibre gastroscopy and colonoscopy for nine FAP patients revealed that four showed a fine granular appearance in the duodenum, three showed lack of lustre, and two showed mucosal friability in the gastrointestinal tract; however, no macroscopic abnormality was observed in four other FAP patients. Histopathological examination of tissue from FAP patients revealed that, although a small amount of amyloid was recognized in the submucosa perivascular layer, a significant amount of amyloid was seen in and around the nerves of the gastrointestinal tract, but very little in Auerbach's nerve plexus. In total, the amount of deposited amyloid in the tissues was small compared with that in other types of systemic amyloidosis, such as AL and secondary amyloidosis. CONCLUSION: These results suggest that the major reason why FAP patients show such severe gastrointestinal symptoms, compared with other types of systemic amyloidosis, may be because of the deposition of a significant amount of amyloid in the nerves in the gastrointestinal tract.

Adult↗

Leb glycolipids present in the lumen of the gastrointestinal tract of rats do not enter the plasma compartment.

We orally administered to rats several times more Leb glycolipids than is proportionally found in the gastrointestinal tract of humans. This was done in an effort to study two potential phenomena: the possibility that glycolipids in plasma may originate from glycolipids derived from the lumen of the gastrointestinal tract, and to investigate the potential to secondarily modify in vivo the glycolipid profile of gastrointestinal tract epithelial cells, a phenomenon clearly established for human erythrocytes, leukocytes, and platelets. We were able to establish that some of the orally administered glycolipids can be detected at the surface of the upper region mucosa of the gastrointestinal tract for more than 24 hours and are essentially excreted intact in stools in less than 72 hours. Some fecal degradation of the Leb glycolipids into Lea and H type 1 did occur. Although we clearly established that the glycolipids were present in the mucus layer adherent to the cell surface, we could not conclusively establish if the glycolipids had inserted into the epithelial cell membrane. This, however, could not be excluded. The fact that the fed glycolipids remained in the mucus layer of the upper region of the gastrointestinal tract for at least 24 hours may have some pharmacological value. Using sensitive techniques, including red cell serology, immunohistology, and immunochemistry of glycolipids isolated from plasma and red cells, there was no evidence that the fed Leb glycolipids reached the plasma compartment, thus suggesting that glycolipids present in the lumen of the gastrointestinal tract cannot reach the circulation.

Journal Article↗

Physical activity and the gastrointestinal tract.

Physical exercise is probably both beneficial and harmful for the gastrointestinal tract, depending partly on the training intensity. On the one hand, gastrointestinal symptoms such as heartburn, chest pain, nausea, vomiting, abdominal cramps, side ache and diarrhoea are common during heavy exercise. On the other hand, physical activity seems to protect from colon cancer, cholelithiasis and diverticular disease. Constipation has been shown to be related to inactivity. Despite this, no overwhelming evidence exists for a positive effect of physical exercise as a treatment option for chronic constipation. The reasons behind these somewhat discrepant effects are not understood fully. Altered gastrointestinal blood flow, effects on gastrointestinal motor function, neuroendocrine changes and mechanical effects are probably involved. Conflicting results exist regarding the effects of physical activity on gastrointestinal motility. Modern technologies now make motility studies in various parts of the gastrointestinal tract possible. More studies are needed to understand better the effects of physical exercise on the gastrointestinal tract. In particular, the relationship between the training intensity and duration and positive and negative alterations in gastrointestinal physiology needs to be addressed further.

Exercise↗

The impact of research quality and study design on epidemiologic estimates of the effect of nonsteroidal anti-inflammatory drugs on upper gastrointestinal tract disease.

BACKGROUND: Considerable differences in the estimates of the risk of upper gastrointestinal tract disease associated with treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) have been observed. We conducted a meta-analysis of epidemiologic studies of upper gastrointestinal tract disease related to NSAIDs to answer the following research questions: Are study characteristics (study design and quality) associated with different estimates of risk, for both aspirin and nonaspirin NSAIDs? Does the risk increase for particular groups of patients, such as women and the elderly? METHODS: Thirty-four studies addressing severe upper gastrointestinal tract disease associated with NSAIDs (including aspirin and nonaspirin NSAIDs) were examined and scored according to a quality checklist that we designed for this review. RESULTS: Only 44% of the studies controlled for major confounding variables (age and sex). While exposure was defined as current in 40% and 78% of the studies for nonaspirin NSAIDs and aspirin, respectively, few investigations checked for history of ulcer disease and concurrent diseases or other comedications known to be risk factors for upper gastrointestinal tract bleeding. The overall risk ratio, by means of a random-effects regression model, was 3.0 (95% confidence interval, 1.9 to 4.7). The individual estimates for aspirin and nonaspirin NSAIDs were similar. Both with and without control for quality, cohort studies provided a lower risk ratio estimate than did case-control studies. CONCLUSIONS: The design and quality of the studies appear to be strong independent predictors of the risk estimate; cohort studies were associated with lower risk estimates than case-control studies, and satisfactory studies were associated with lower risk estimates than unsatisfactory studies.

Aged↗

Frozen section of the gastrointestinal tract, appendix, and peritoneum.

CONTEXT: Intraoperative consultation is frequently requested by surgeons operating on the gastrointestinal tract, appendix, and peritoneum. In this setting, the pathologist's diagnosis plays a central role in determining whether a resection is needed, and if so, how much to resect and whether it was adequate. There is no room for errors in the frozen section laboratory, because a small mistake can have serious consequences. To my knowledge, no recent books or publications in the literature have dealt with this important topic. OBJECTIVE: To review the intraoperative consultation of the gastrointestinal tract, appendix, and peritoneum. DATA SOURCES: The MEDLINE database was queried for keywords, including gastrointestinal, esophagus, stomach, esophageal, gastric, small intestine, and all other names of the gastrointestinal tract, peritoneum, and appendix in combination with frozen section. All suitable articles were retrieved and reviewed. This literature search and my personal experience formed the basis of this review. CONCLUSIONS: The role, value, and limitations of frozen section and gross consultation are different for different areas of the gastrointestinal tract, even for the same types of lesions. Close interaction with the surgeon and knowing what is intended from the frozen section, what will be done following a certain diagnosis, and what is the minimal information needed from the pathologist at the time of frozen section are essential for proper patient management.

Appendicitis↗

Adaptation for water balance in the partial gastrointestinal tract of summer flounder.

Marine teleosts continually drink and absorb water across the intestine to prevent dehydration. Surprisingly, summer flounder that are missing most of their intestine, due to necrotizing enteritis, maintain osmotic homeostasis. Here, we tested the hypothesis that this remnant gastrointestinal tract undergoes compensatory adaptation for fluid uptake. Flounder (Paralicthys dentatus) with a partial gastrointestinal tract had an emaciated liver. Moisture content of muscle however was similar to healthy cohorts with an intact gastrointestinal tract, indicative of an undisturbed osmoregulatory status. Mass-specific rates of fluid uptake across all segments of the partial gastrointestinal tract were less than or similar to rates in corresponding segments from intact flounder. In contrast, weights (percent of body mass) were doubled in stomach and partial intestine of the remnant gastrointestinal tract. Consequently, total capacity for fluid uptake (microL h(-1) g body mass(-1)) was similar for both groups. The functional capacity of the remnant gastrointestinal tract was therefore of a magnitude sufficient to maintain osmoregulatory ability, further evidencing a critical role of the intestine in salt and water balance of marine teleosts.

Acclimatization↗

Ethanol and the antioxidant defense in the gastrointestinal tract.

Ethanol is known to have profound actions on the gastrointestinal tract. The present study was undertaken to examine the effects of ethanol on some of the natural antioxidant defensive enzymes in the gastrointestinal tract; the activities of these enzymes in the liver and the brain were also measured for comparison with those in the gastrointestinal tract. Oral administration of absolute ethanol induced severe gastric mucosal lesions and also damage in the small intestine, however the total superoxide dismutase was unaffected in the tissues measured. The glucose-6-phosphate dehydrogenase activity was reduced only in the stomach while the total glutathione was elevated in the small intestinal mucosa. The catalase activities were activated in the stomach, small and large intestines, and brain, but not in the liver which contained the highest concentration of the enzyme. The present findings indicate that endogenous hydrogen peroxide may be an important damaging agent towards biomolecules in different organs and the removal of this by catalase represents an important defensive mechanism against ethanol toxicity.

Animals↗

Structure and function of the gastrointestinal tract in infants and children.

An understanding of gastrointestinal tract development is essential in understanding the pathology and management of common structural anomalies and functional disorders in the pediatric population. This article reviews key steps in the embryologic development of the gastrointestinal tract and the acquisition of fecal continence, with brief explanations of common functional and structural disorders.

Child↗

A prospective evaluation of the upper gastrointestinal tract and periampullary region in patients with Gardner syndrome.

Neoplasms of the upper gastrointestinal tract and periampullary region occur in patients with Gardner syndrome (GS), but their true incidence is not yet established. Fourteen patients with GS underwent esophagogastroduodenoscopy prior to colectomy and every 1-3 years thereafter. In 10 patients the pancreatobiliary system was also investigated: nine by endoscopic retrograde cholangiopancreatography and one at autopsy. All of the patients underwent ultrasound examination of liver, biliary tree, and pancreas. Adenomas in the upper gastrointestinal tract were found in all of the patients: Vater's papilla--12, duodenum--nine, and gastric antrum--seven. Only five patients had adenomas at the time of diagnosis of GS, and all the others developed adenomas within a mean of 2.5 years. One patient had hyperplastic polyps in the stomach fundus. Adenomas of the papilla of Vater demonstrated a higher degree of dysplasia compared to dysplasia in other locations of the gastrointestinal tract. Endoscopic retrograde cholangiopancreatography helped in detecting adenomas in distal common bile duct not visible at endoscopy. We conclude that adenomas at the upper gastrointestinal tract occur frequently in patients with GS and, therefore, periodic endoscopic systematic investigation of all patients with GS is mandatory.

Adenoma↗

Histiocytic subpopulations in the gastrointestinal tract: distribution and possible relationship to function.

The distribution of specific histiocyte subsets within the human gastrointestinal tract has not been extensively characterized. Our goal was to immunohistochemically evaluate the distribution and location of CD1a-positive, CD68-positive, and Factor XIIIa (FXIIIa)-positive histiocyte subsets within the normal gastrointestinal tract and attempt to relate distribution to possible function. Twenty-nine samples of normal esophagus, stomach, small bowel, large bowel, and anus were routinely processed and immunohistochemically stained with antibodies to CD68, CD1a, and FXIIIa. The distribution and histologic location of histiocyte subsets were qualitatively analyzed. CD1a-positive cells were seen exclusively within anal and esophageal squamous mucosa. CD68 positive histiocytes were present in lamina propria and submucosa throughout the gastrointestinal tract and in Peyer patches. FXIIIa-positive histiocytes were also abundant in lamina propria and submucosa throughout the gastrointestinal tract, particularly around pericryptal sheaths and in parafollicular regions surrounding Peyer patches. Our results showed that there are distinct subpopulations of gastrointestinal histiocytes, and that distribution varies according to both cell type and site. Because Langerhans cells are epidermal antigen processing/presentation cells, their exclusive presence in squamous mucosa suggests an analogous function there. The prominence of both CD68 and FXIIIa-positive cells surrounding glandular pericryptal sheaths suggests that they are important to immune function at this mucosal interface and may play a role in communication between glands and lamina propria. In addition, the presence of specific histiocyte subsets within Peyer patches and para-follicular regions suggests that they are involved in different aspects of antigen processing associated with gut lymphoid tissue. Further studies are needed to explore the relation between specific histiocyte subsets and gastrointestinal disease processes.

Antigens, CD↗

[Primary amyloidosis of the gastrointestinal tract and liver--two case reports].

In primary amyloidosis the gastrointestinal tract and the liver are commonly involved, but clinical features and prognosis are mainly determined by the extent of cardiac and renal involvement. We review two cases with primary amyloidosis of the gastrointestinal tract and the liver. The predominant symptoms were malabsorption and hepatomegaly with cholestasis. The clinical aspects, diagnosis, treatment and prognosis of primary amyloidosis of the gastrointestinal tract and the liver are discussed in the context of the current literature.

Amyloidosis↗

Risk of hospitalization for upper gastrointestinal tract bleeding associated with ketorolac, other nonsteroidal anti-inflammatory drugs, calcium antagonists, and other antihypertensive drugs.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) cause substantial morbidity and mortality from upper gastrointestinal tract disease. Ketorolac tromethamine has been singled out as an NSAID with a distinct gastrotoxicity profile. Calcium channel blockers, a class of antihypertensive drugs, have also been found to increase the risk of gastrointestinal tract bleeding. METHODS: We identified 1505 patients hospitalized because of upper gastrointestinal tract bleeding and/or perforation, and we randomly sampled 20,000 controls in the source population. RESULTS: The adjusted relative risk (RR) for upper gastrointestinal tract bleeding and/or perforation in NSAID users compared with nonusers was 4.4 (95% confidence interval [CI], 3.7-5.3). The risk increased with higher daily doses. Ketorolac presented the highest risk (RR, 24.7; 95% CI, 9.6-63.5) and piroxicam ranked second (RR, 9.5; 95% CI, 6.5-13.8). Ketorolac was 5 times more gastrotoxic than all other NSAIDs (RR, 5.5; 95% CI, 2.1-14.4). The excess risk with ketorolac was observed with both oral and intramuscular administration and was already present during the first week of therapy. Among the various antihypertensive drug classes, beta-blockers were associated with the lowest relative risk (RR, 1.0; 95% CI, 0.7-1.4), and current use of calcium channel blockers with the highest (RR, 1.7; 95% CI, 1.3-2.1). The association with calcium channel blockers declined when adjusting for various markers of comorbidity (RR, 1.4; 95% CI, 1.1-1.8). Past use of calcium channel blockers was also associated with an increased risk (RR, 1.5; 95% CI, 1.3-1.8). CONCLUSIONS: The excess risk of major upper gastrointestinal tract complications associated with outpatient use of ketorolac suggests an unfavorable risk-benefit assessment compared with other NSAIDs. More data are required to reduce the uncertainty about the apparent small increased risk of upper gastrointestinal tract bleeding in patients using calcium channel blockers.

Adult↗

Diffuse lymphomatous polyposis of the gastrointestinal tract. A case report with immunohistochemical studies.

A case of diffuse lymphomatous polyposis of the gastrointestinal tract is reported. The patient presented with abdominal pain and weight loss and x-rays revealed multiple polyps involving the entire gastrointestinal tract. Biopsies confirmed the diagnosis of lymphomatous polyposis. The patient also had involvement of the bone marrow and supraclavicular lymph node. Immunologically this lymphoma was characterized as a monoclonal proliferation of B lymphocytes bearing immunoglobulin M, type kappa. Diffuse lymphomatous polyposis of the gastrointestinal tract appears to be a generalized malignancy of uncommitted B cells of Peyer's patches. The migratory properties of these cells may account for the tendency to dissemination of lymphomatous polyposis. Diffuse lymphomatous polyposis of the gastrointestinal tract is a distinct entity, separate from the diffuse gastrointestinal lymphoma known as Mediterranean-type lymphoma.

Aged↗

Complications of stent placement for benign stricture of gastrointestinal tract.

AIM: To observe the frequent complications of stent placement for stricture of the gastrointestinal tract and to find proper treatment. METHODS: A total number of 140 stents were inserted in 138 patients with benign stricture of the gastrointestinal tract. The procedure was completed under fluoroscopy in all of the patients. RESULTS: Stents were successfully placed in all the 138 patients. Pains occurred in 23 patients (16.7%), slight or dull pains were found in 21 patients and severe chest pain in 2 respectively. For the former type of pain, the patients received only analgesia or even no treatment, while peridural anesthesia was conducted for the latter condition. Reflux occurred in 16 of these patients (11.6%) after stent placement. It was managed by common antireflux procedures. Gastrointestinal bleeding occurred in 13 patients (9.4%), and was treated by hemostat. Restenosis of the gastrointestinal tract occurred in 8 patients (5.8%), and was apparently associated with hyperplasia of granulation tissue. In 2 patients, the second stent was placed under X-ray guidance. The granulation tissue was removed by cauterization through hot-node therapy under gastroscope guidance in 3 patients, and surgical reconstruction was performed in another 3 patients. Stent migration occurred in 5 patients (3.6%), and were extracted with the aid of a gastroscope. Food-bolus obstruction was encountered in 2 patients (1.4%) and was treated by endoscope removal. No perforation occurred in all patients. CONCLUSION: Frequent complications after stent placement for benign stricture of the gastrointestinal tract include pain, reflux, bleeding, restenosis, stent migration and food-bolus obstruction. They can be treated by drugs, the second stent placement or gastroscopic procedures according to the specific conditions.

Adolescent↗