Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “GASTROINTESTINAL TRACT”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 487 records · Page 27Linked to original sources
PubMed1980

Effects of autonomic stimulation on the release of vasoactive intestinal peptide from the gastrointestinal tract in the calf.

1. The effects of autonomic stimulation on the release of vasoactive intestinal peptide (VIP) from the gastrointestinal tract have been investigated in adrenalectomized claves 2-5 weeks after birth.2. Stimulation of the peripheral ends of the splanchnic nerves (10 Hz for 10 min) caused a small fall in the concentration of VIP in portal and arterial plasma, together with a rise in the concentration in intestinal lymph. None of these changes achieved statistical significance.3. The effects of stimulation of the peripheral ends of the thoracic vagi, below the heart (10 Hz for 10 min), were found to depend in part upon the integrity of the splanchnic sympathetic innervation. A substantial rise in the concentration of VIP in intestinal lymph occurred whether or not the splanchnic nerves had been cut whereas an associated rise in arterial plasma VIP was only observed in calves in which the splanchnic nerves had been sectioned.4. The rise in the concentration of VIP in intestinal lymph, in response to vagal stimulation, was unaffected by concomitant stimulation of the splanchnic nerves, although the associated rise in arterial plasma VIP concentrations was suppressed. The response was also found to be resistant to atropine.5. The minimum estimated concentration of VIP in the extracellular fluid of the gastrointestinal tract was estimated to be about 60 p-mole/l. at rest and to rise by 70-120 p-mole/l. in response to vagal stimulation.6. Intravenous infusions of VIP at a dose of 50 ng kg(-1) min(-1) (16 p-mole kg(-1) min(-1)), which raised the minimum estimated concentration of VIP in the gastro-intestinal tract to the highest range encountered during stimulation, produced no significant changes in the concentrations of glucose, insulin, pancreatic glucagon or pancreatic polypeptide in the arterial plasma.7. It is concluded that a small amount of VIP is released from the gastrointestinal tract in response to vagal stimulation. In contrast, release of VIP is unaffected by stimulation of the splanchnic nerves except in so far as the rate at which the peptide passes into the circulation is reduced by adrenergic vasoconstriction.

Animals↗
PubMed2004

Endoscopic and histological changes in upper gastrointestinal tract of patients with chronic renal failure.

To evaluate the endoscopic and histological changes in upper gastrointestinal tract of patients with chronic renal failure 50 patients and 50 controls were studied. Upper gastrointestinal endoscopy was done and 2 biopsies each were taken from oesophagus, corpus and antrum of the stomach and duodenum. Sections were stained with haematoxylin & eosin, Alcian blue--Periodic acid Schiff's (pH 2.5), and Loeffler's methylene blue stains. Oesophagus was endoscopically normal in most of the patients. Predominant histological finding was chronic oesophagitis which was significantly higher in patients than controls (47.1% Vs 26%; p<0.05). Significantly higher (p<0.001) number of patients had gastritis, oedema and pale mucosa on endoscopic examination of stomach. Predominant histological changes were mucosal oedema (82.35%), gastritis (23.5%) and increase in number of bi- and multinucleated parietal cells with vacuolation and fragmentation of the cytoplasm (29%). Prevalence of H. pylori was less in patients as controls (35.2% Vs 54%; p< 0.01). Endoscopic examination of duodenum mainly showed duodenitis, pale mucosa, oedema and nodularity. Brunner's gland hyperplasia (82.4%), duodenitis (70.6%) and gastric metaplasia (29.4%) were the main histological features. H. pylori was seen in 5.9% cases of gastric metaplasia in duodenum. Patients with CRF have significant upper gastrointestinal tract abnormalities which mainly occur due to metabolic changes in response to high urea concentration in gastric juice and are not related to H. pylori infection.

Adult↗
PubMed1997

Biliodigestive shunt evokes hyperCCKemia and trophic effects in the rat pancreas, but not in the liver or gastrointestinal tract.

The influence of bile on the release of cholecystokinin (CCK) and, thereby, on the regulation of exocrine pancreatic function and growth is unsettled. The aim of this study was to elucidate the effect of long-term diversion of bile from the upper small intestine of CCK release and on the pancreas, liver, and gastrointestinal tract. A surgical biliodigestive shunt was performed in rats, diverting the bile flow directly to the middle of the small intestine. The animals were killed after 4 or 12 weeks. Plasma CCK and trophic effects on the pancreas, liver, and gastrointestinal tract were determined, as were the trypsin and chymotrypsin contents in the intestine. The CCK concentration in plasma increased 10-fold at both time points studied. The pancreas doubled its weight from 4 weeks onward. Also, pancreatic protein, DNA, and amylase contents were increased throughout the study. The liver and gastrointestinal tract were unaffected. Intraluminal bile plays a role in the feedback regulation of CCK release and is involved in this way in the control of pancreatic growth but has no similar effects on the liver or gastrointestinal tract.

Amylases↗
PubMed1987

Dysplasia in the gastrointestinal tract: definition and clinical significance.

The term "dysplasia" is used increasingly in gastrointestinal pathology. Dysplasia denotes an unequivocal neoplastic epithelial alteration without invasive growth and is synonymous with the term "intraepithelial neoplasia." Dysplasia is the paradigm of a precancerous lesion. Confusion arises because some pathologists do not use the term in the above-defined sense but to describe regenerative, inflammatory and reactive changes. It is essential to separate these kinds of non-neoplastic epithelial changes from neoplastic dysplasia because the clinical consequences are completely different. The general morphology and the grading of dysplasia are described. Most dysplasias in the gastrointestinal tract are the polypoid lesion; dysplasias in flat mucosa are uncommon. Knowledge of the incidence of dysplasia in the gastrointestinal tract is important for the concept of secondary cancer prevention.

Gastrointestinal Neoplasms↗
PubMed1950

Radioiron absorption in anemic dogs; fluctuations in the mucosal block and evidence for a gradient of absorption in the gastrointestinal tract.

The control of iron absorption appears to reside in the mucosa of the gastrointestinal tract. The normal dog absorbs very little iron, but the anemic iron-depleted dog may absorb 10 to 20 times as much. This "mucosal block" of the normal dog probably is due largely to iron stores in the mucosa. "Mucosal block" can be effected in the anemic iron-depleted dog by feeding of iron salts, but the degree of "mucosal block" under these conditions never reaches the high degree of "mucosal block" in the normal dog. Rapid movement of iron through the mucosa may explain the short duration of "mucosal block" due to iron feeding in the anemic iron-depleted dogs (18 to 20 hours, Fig. 1). The colon absorbs very little iron under the conditions described. The stomach and duodenum seem to be most active in its absorption. This suggests the existence of a gradient in the capacity of the gastrointestinal tract to absorb iron.

Anemia↗
PubMed1997

Double-contrast barium examination of the upper gastrointestinal tract with nonendoscopic biopsy: findings in 100 patients.

PURPOSE: To evaluate the performance of double-contrast barium examination of the upper gastrointestinal tract augmented with nonendoscopic gastric mucosal biopsy. MATERIALS AND METHODS: One hundred twenty-six patients (aged 9-81 years) underwent double-contrast barium examination of the upper gastrointestinal tract and nasogastric biopsy. Pathology reports were recovered for 100 patients. These patients' records were searched for procedural complications, sufficiency of biopsy tissue, diagnoses among various age groups, and radiographic findings. RESULTS: Forty-nine (49%) of the 100 patients had biopsy-proved Helicobacter pylori infection with chronic active gastritis. Twenty-one patients (21%) with H pylori-negative biopsy specimens had chronic gastritis. One patient with eosinophilic gastritis and one with granulomatous gastritis were identified. Twenty-nine patients (29%) had negative biopsy results. Nineteen (30%) of the patients with negative barium studies had a positive biopsy specimen, and four (6%) of the patients with positive barium studies had negative biopsy specimens. Eight patients (8%) had a second diagnosis of intestinal metaplasia. CONCLUSION: Use of double-contrast barium examination of the upper gastrointestinal tract combined with nonendoscopic biopsy is quick and safe and can provide reliable histologic information to the primary care physician.

Adolescent↗
PubMed2005

Gastrointestinal tract perforation in dogs treated with a selective cyclooxygenase-2 inhibitor: 29 cases (2002-2003).

OBJECTIVE: To identify factors associated with gastrointestinal tract perforation in dogs being treated with a selective cyclooxygenase-2 (COX-2) inhibitor (deracoxib). DESIGN: Retrospective study. ANIMALS: 29 dogs. PROCEDURE: The Novartis Animal Health pharmacovigilance database was searched for records of dogs treated with deracoxib in which gastrointestinal tract perforation was documented. Results-16 of the 29 (55%) dogs had received deracoxib at a dosage higher than that approved by the FDA for the particular indication being treated, with 25 (86%) dogs having received deracoxib at a dosage > 2 mg/kg/d (0.9 mg/lb/d). Seventeen (59%) dogs had received at least 1 other nonsteroidal anti-inflammatory drug (NSAID) or a corticosteroid in close temporal association (within 24 hours) with deracoxib administration (ie, immediately before or following). In all, 26 (90%) dogs had received deracoxib at a higher-than-approved dosage or had received at least 1 other NSAID or corticosteroid in close temporal association with deracoxib administration. Twenty dogs died or were euthanatized, and 9 survived. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with gastrointestinal tract perforation and that had been treated with deracoxib, perforation was most likely attributable to a number of factors. Deracoxib should only be used at approved dosages. Cortico-steroids and other less selective NSAIDs should not be administered in close temporal association with selective COX-2 inhibitors, including deracoxib. Further study is required to define this problem.

Acute Disease↗
PubMed1993

Structural transformation of lignan compounds in rat gastrointestinal tract; II. Serum concentration of lignans and their metabolites.

Serum concentrations of arctiin, tracheloside, and their metabolites formed in the gastrointestinal tract were investigated in the rat. Arctiin or tracheloside was not detected in the serum after oral administration (200 mg/kg). In regard to their metabolites, each metabolite 1 (AM1, TM1), their genuine genins, appeared in the serum, and the serum concentration of arctiin metabolite 1 (AM1) reached its peak at 4 h and that of tracheloside metabolite 1 (TM1) reached its peak at 8 h. On the other hand, both metabolites 2 (AM2, TM2), which each possess a catechol moiety as reported previously, were not found in the serum. Now, we have studied the detection of their metabolites in the rat large intestinal contents after oral administration. It was revealed that all metabolites reported previously were certainly formed in rat gastrointestinal tract in vivo. Thus, we presumed a possibility that metabolite 2 was converted into metabolite 1 through C-3" methylation by catechol-O-methyltransferase (COMT) in rat liver. Each metabolite 2 was incubated with rat liver cytosol in the presence of S-adenosyl-L-methionine. It was proved that metabolite 2 was rapidly converted into metabolite 1 within 3 min. We suggest that arctiin or tracheloside was transformed to at least two metabolites in the gastrointestinal tract, and after absorption from the intestine, metabolite 2 was converted into metabolite 1 through methylation by COMT in the liver, and arctiin and tracheloside existed as metabolite 1, the genuine genin, in the blood stream.

4-Butyrolactone↗
PubMed1999

The application of ecological principles and fermentable fibers to manage the gastrointestinal tract ecosystem.

Because diet can influence the structure and functions of the gastrointestinal tract, there are opportunities for using diet as a "management tool" to affect the resident microbiota. Fermentable fibers increase the densities of beneficial bacteria and stimulate growth and functions of the healthy intestine. Recent findings show that after acute diarrhea, the use of an oral electrolyte solution with the fermentable fiber oligofructose accelerates recovery of beneficial bacteria, reduces the relative abundance of detrimental bacteria, stimulates mucosal growth and enhances digestive and immune functions. This review will focus on how the principles of stream ecology can be applied to better understand the distribution of bacteria along the length of the gastrointestinal tract, the effect of diarrhea on the gastrointestinal ecosystem and how fermentable fibers can be used as a "management tool" to promote gastrointestinal health in normal states and during recovery from diarrhea.

Acute Disease↗
PubMed2006

Drug-induced side effects affecting the gastrointestinal tract.

With the ever-growing armamentarium of pharmacological agents, the gastrointestinal drug-induced side effects of dyspepsia, nausea, vomiting, diarrhoea and constipation are increasingly seen. They are often self-limiting and without serious sequelae, but of greater concern is drug-induced mucosal ulceration that can manifest as gastrointestinal haemorrhage, stricture and perforation. These complications are mainly attributable to NSAIDs and aspirin, which can injure the mucosa anywhere along the gastrointestinal tract. These iatrogenic serious side effects can be reduced with co-prescription of a proton pump inhibitor, substitution of a COX-2 inhibitor and eradication of Helicobacter pylori when the bacterium is present. Other recognised gastrointestinal complications include small intestinal diaphragm, microscopic colitis, a range of hepatotoxic effects and pancreatitis. The introduction of new classes of drugs has resulted in new adverse effects that require consideration in patients presenting with gastroenterological symptoms. These include pill oesophagitis from bisphosphonates and ischaemic colitis relating to serotonin antagonists. Here, the authors review the literature on drug-induced complications of the gastrointestinal tract and present the pertinent management issues relevant to clinical practice.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1988

Anastomotic strictures of the upper gastrointestinal tract: results of balloon dilation.

Enteroenteric anastomotic strictures of the upper gastrointestinal tract are common and require treatment if significant obstruction occurs. The authors performed 44 fluoroscopically guided balloon dilations in 19 patients with symptomatic anastomotic strictures. The anastomoses were esophagoesophageal (n = 5), esophagogastric (n = 8), esophagoileocolonic (n = 4), and gastrojejunal (n = 2). Nine patients required only one balloon dilation for stricture lysis and relief of clinical symptoms. Recurrent symptoms developed in the remaining ten patients, who required two to eight dilations. Radiographically, stenoses made up 40%-90% of the anastomotic lumen before dilation (mean, 72%). Complete resolution of the stricture was achieved during the procedure in 24 instances. Residual stenosis in 18 instances varied from 7% to 45% (mean, 21%). Two complications, a mucosal tear and a perforation, were immediately recognized and successfully treated non-operatively. The authors conclude that fluoroscopically guided balloon dilation has an important role in the treatment of anastomotic strictures of the upper gastrointestinal tract.

Anastomosis, Surgical↗
PubMed1984

Multiple lymphomatous polyposis of the gastrointestinal tract.

Multiple lymphomatous polyposis (MLP) is a distinctive type of primary gastrointestinal lymphoma characterized by polypoid accumulations of lymphoma tissue involving long segments of the gastrointestinal tract. A study of four cases of MLP has shown a tendency for ileocaecal involvement and extra-abdominal dissemination. The lymphoma is of centrocytic type and exhibits a nodular pattern of variable degree. Trapping of reactive follicle centres with replacement of their mantle zones is characteristic. Immunohistochemical studies show a high concentration of monotypic SIg demonstrable in both cryostat and paraffin sections together with the other features of malignant lymphoma, centrocytic. The histological features of MLP bear a close resemblance to those of intermediate cell and mantle zone lymphoma, as described by American workers, which suggests that these two conditions and malignant lymphoma, centrocytic, are the same entity. In the gastrointestinal tract malignant lymphoma, centrocytic, produces a characteristic classic clinicopathological picture (MLP). In view of its less favourable prognosis it is important to distinguish MLP from other primary gastrointestinal lymphomas of follicle centre cell origin.

Aged↗
PubMed2001

Endoscopy for acute nonvariceal upper gastrointestinal tract hemorrhage: is sooner better? A systematic review.

BACKGROUND: While the effectiveness of upper endoscopy has been established for acute nonvariceal upper gastrointestinal tract hemorrhage, its optimal timing has not been clearly defined. Early endoscopy has been advocated for its ability to achieve prompt diagnosis, risk stratification, and therapeutic hemostasis. OBJECTIVE: To determine whether early vs delayed endoscopy improves patient and economic outcomes for all risk groups with nonvariceal upper gastrointestinal tract hemorrhage. METHODS: A systematic review of 3 computerized databases (MEDLINE, HEALTHSTAR, and Cochrane Database of Systematic Reviews) was performed along with hand searching of published abstracts to identify English-language citations from 1980 to 2000. RESULTS: Twenty-three studies met explicit inclusion criteria. The highest-quality study examining outcomes in low-risk patients found no significant complications at 1-month follow-up for any outpatients managed with early endoscopy. The largest randomized trial of high-risk patients showed no mortality benefit but a significant decrease in transfusion requirements with early endoscopy. Seven of the 8 studies examining the effect of early endoscopy on length of stay as a measure of resource utilization demonstrated a significant reduction compared with that of delayed endoscopy. However, most included studies were found to suffer from 1 or more potentially significant methodologic shortcomings. CONCLUSIONS: The overwhelming majority of existing data suggest that early endoscopy is safe and effective for all risk groups. The clinical and economic outcomes of early endoscopy should be confirmed in additional well-designed randomized controlled trials. Given the strength of the evidence, efforts to develop a more standardized and time-sensitive approach to acute nonvariceal upper gastrointestinal tract hemorrhage should be undertaken.

Endoscopy, Gastrointestinal↗
PubMed1993

Isolation of Acinetobacter calcoaceticus from the gastrointestinal tracts of SCID mice.

Acinetobacter calcoaceticus colonization was observed in the gastrointestinal tracts of C.-B17-scid/scid (SCID) mice, while it was not observed in C.B17-scid/+ and C.B17-+/+ mice with normal immunity housed under the same conditions. A. calcoaceticus and other viable enteric bacteria were not isolated from any organs other than gastrointestinal tract in SCID mice. The mice colonized with this organism were apparently healthy and no significant visceral lesion was observed.

Acinetobacter calcoaceticus↗
PubMed1995

Host-microbe interaction in the gastrointestinal tract.

In order for an infection to occur, the target organ must come in contact with sufficient microbes, the microbe must possess specific virulence factors, these virulence factors must be expressed, and the defenses of the organ system must be overcome. This dynamic process, which is ongoing in all living entities, can be described by the following relationship: [formula: see text] The establishment of infection first occurs in a particular organ. This phenomenon is known as tissue trophism and the association of microbes with organ systems governs the practice of clinical microbiology and infectious disease. With some microbes (e.g., Giardia, Cryptosporidium) the interaction with the particular organ is so specific that infections are almost always confined to one site; with others (e.g., Salmonella, enterovirus) the microbe has the potential to become systemic. When attempting to establish health risk assessment from microbes by contact with food and drinking water, one must therefore consider that the gastrointestinal tract is a complex organ system with a variety of specific host defense mechanisms. It is only when the microbe has particular virulence factors for sites in gastrointestinal tract, and the specific host defense mechanisms in the gastrointestinal tract are breached, that infection of this organ system occurs. Therefore, the general terms "immunosuppression" or "immunocompromise" are meaningless unless the specific immune defect is known. A description of the microbial virulence factors active against the gastrointestinal tract and the defense mechanisms of this organ system are reviewed to provide a biological basis health risk assessment and future food and drinking water regulations.

Antibody Formation↗
PubMed1977

A prospective, randomised study of endoscopy and radiology in acute upper-gastrointestinal-tract bleeding.

318 patients admitted to hospital with acute upper-gastrointestinal-tract bleeding were entered into a prospective randomised comparison of investigation by either endoscopy or radiology. Although the diagnostic yield was higher in the endoscopy group than the radiology group, there was no difference between the two groups in management or survival, and the accuracy of the findings as judged independently at operation and/or necropsy was also similar in the two groups. These findings case doubt on the need to provide emergency endoscopic facilities for the investigation of patients with acute upper-gastrointestinal-tract bleeding where radiological services are already adequate.

Acute Disease↗
PubMed2001

[Clinical significance of micrometastasis to lymph nodes in gastrointestinal tract cancers].

Surgery is the main therapy for malignancies of the gastrointestinal tract. Lymph node metastasis is one of the major factors in predicting patients' clinical course and choosing appropriate adjuvant therapy after surgery. The concept of micrometastasis to regional lymph nodes emerged over 10 years ago, but its significance has been controversial. To clarify the relevance of micrometastasis of gastrointestinal tract cancers, we have established RT-PCT based-diagnostic methods using multi-markers such as CEA, CK20, and Mage 3. Prospective studies have shown that not a few micrometastasis-positive patients with carcinoma of the colon, stomach, and esophagus suffered disease recurrence, even though they did not show histologically positive lymph node metastasis. They were initially diagnosed as node-negative, and thus predicted to be disease free. A retrospective study of 62 patients with stage II node-negative colorectal cancer showed that 5-year overall survival was 78.2% among micrometastasis-positive patients, against 95.3% micrometastasis-negative patients. Moreover, there was a marked difference in 5-year disease-free survival, with 61.4% versus 88.4%, respectively. These data warrant further prospective study with a large population since RT-PCR based detection systems for micrometastasis appear to have the potential to improve conventional diagnosis and therapy for colorectal cancer.

Biomarkers, Tumor↗
PubMed2004

Therapeutic efficacy and safety of percutaneous radiofrequency ablation of hepatocellular carcinoma abutting the gastrointestinal tract.

OBJECTIVE: The purpose of this study was to evaluate the therapeutic efficacy and safety of percutaneous radiofrequency ablation in the treatment of hepatocellular carcinomas abutting the gastrointestinal tract. MATERIALS AND METHODS: Forty-one patients with hepatocellular carcinomas abutting the gastrointestinal tract underwent sonographically guided percutaneous radiofrequency ablation. Forty-one tumors (1.2-4.3 cm in maximum diameter) had parts 5 mm or greater (or at least one quarter of their circumferences) abutting the stomach in 23 patients and the colon in 18 patients. Thirty tumors were ablated with internally cooled electrodes and 11 with multitined expandable electrodes. All patients were followed up for at least 1 year after ablation. Therapeutic efficacy and safety were evaluated with follow-up sonography and multiphase helical CT. RESULTS: At 1-month follow-up CT, three (7%) of the 41 tumors showed residual unablated tumor in the ablation zone. Of the remaining 38 hepatocellular carcinomas (93%) with no evidence of residual unablated tumor, four (11%) showed local tumor progression in the ablation zones on subsequent follow-up CT. We observed one major complication-a small perihepatic abscess-that needed specific treatment. CONCLUSION: Percutaneous radiofrequency ablation is an effective and safe technique for treating hepatocellular carcinomas abutting the gastrointestinal tract.

Adult↗