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At least 469 records · Page 26Linked to original sources
PubMed2002

Seasonal changes in morphology and function of the gastrointestinal tract of free-living alpine marmots ( Marmota marmota).

The gastrointestinal tracts of 76 free-living alpine marmots ( Marmota marmota) shot during a population control program in Switzerland were collected and analysed for patterns of change in morphology and function over the period from emergence from hibernation in April to just before re-entry into hibernation in September. Between first emergence and mid-summer (July) the fresh tissue mass of the stomach increased by 105%, the small intestine by 259% (among the largest recorded for a mammal), caecum by 185%, proximal colon by 138%, and distal colon by 144%. Mitotic activity was greatest in the small intestine; the mitotic index was high (40%) compared with indexes in the stomach and hindgut (approximately 4%) even at emergence, and increased to approximately 60% by mid-summer. Microbial activity in the caecum was also significant at emergence. The stomach (length) and caecum (length and fresh mass) increased in response to ingested food earlier than did the small intestine. Between mid-summer and September there were decreases in small intestinal tissue mass and mitotic activity. It is concluded that the gastrointestinal tract of alpine marmots probably continues to function throughout hibernation at a low level, with a mid-winter trough as part of an endogenous circannual rhythm. However, after emergence in spring, increases in size and activity of the tract appear to be a response to ingested food rather than to an endogenous signal. The early signs of down-regulation of the small intestine before re-entry into hibernation, together with its delayed up-regulation in response to food in spring, are consistent with the high costs of maintaining this section of the digestive system.

Animals↗
PubMedDate not supplied

[The gastrointestinal tract in H.I.V. patients. Anatomopathologic aspects of opportunistic infections].

The symptoms of the Acquired Immuno-Deficiency Syndrome (A.I.D.S.) in the gastrointestinal tract are principally represented by neoplastic processes (Kaposi's sarcoma, lymphoma) and by opportunistic infections. These infections, for the diversity of bacterial, viral or parasitic etiological agents which are involved, ask for new and more specific interpretative problems, from the pathological point of view-either in the identification of the pathogenic agents either in the recognition of infective lesions associated with the presence of a not directly objectivable infective agent. On the basis of these considerations the authors report the principal histopathological characteristics connected with opportunistic infections of the gastrointestinal tract in 18 H.I.V. positive patients. Of every segment of the gastrointestinal tract, the detected agents are described with the lesions related to them, the other not specific A.I.D.S. associated infective forms recently described in literature, and in particular the differential diagnostic problems connected with viral infections. In the large bowel must be underlined the problems and the principal distinctive elements between opportunistic agents derived colitis and idiopathic colitis.

Acquired Immunodeficiency Syndrome↗
PubMed2001

[Endoscopic mucosal resection of premalignant lesions of the upper gastrointestinal tract].

BACKGROUND: Surgical therapy of early malignancies of the upper gastrointestinal tract is associated with substantial morbidity and mortality, especially in elderly and co-morbid patients. In Japan endoscopic mucosal resection (EMR) has been proven to be safe and efficacious in this indication. PATIENTS AND METHODS: 22 patients (68 +/- 14 years, 9 females) with high-grade dysplasia of the esophagus (n = 5), early carcinoma of the esophagus (T1N0M0, n = 11) or early gastric cancer (T1N0M0, n = 6) proven by high-resolution videoendoscopy (plus chromoendoscopy in most cases), miniprobe-endosonography (12-20 MHz) and biopsy were enrolled. The lesion size ranged from 7-40 mm in diameter. EMR was performed using a monofile snare, in almost all cases after submucosal injection of an attenuated epinephrine-solution (1:20,000) to effect a lifting sign. "En bloc" resection was possible in 17/22 cases (77 %), but in 5 patients piecemeal-resection had to be performed due to a larger lesion size. RESULTS: Active bleeding occurred on 14 of 22 occasions (64 %), in another 5 patients secondary bleeding (within 24 h after EMR) were detected. All these events could be managed endoscopically (mainly by hemoclip application) and blood transfusion was not required. Other complications did not occur. A complete resection (R0) was achieved in 21/22 cases, however, one patient had to undergo a second EMR procedure because histology of the first resected specimen had revealed malignant infiltration of the resection margin (R1). After the second EMR procedure complete (R0)-resection was obtained. Compared to the histological findings after EMR the pre-procedural staging proved to be correct in all cases. The control examinations (clinical exam, lab data, endoscopy with multiple biopsies, endosonography and CT) after EMR revealed no local or systemic cancer recurrence in 21/22 patients (median follow-up 5 months, range 3-12 months). However, in one patient with adenocarcinoma and Barrett-esophagus another mucosal adenocarcinoma was detected 3 months after EMR (located in opposite to the initial carcinoma treated with EMR). CONCLUSION: EMR seems to be a safe and effective (regarding local tumor control) therapy for high-grade dyplasia and early malignancies in the upper gastrointestinal tract. However, long-term follow-up in these patients has to be awaited.

Adenocarcinoma↗
PubMed1993

Multiple lymphomatous polyposis of the gastrointestinal tract.

We report two rare cases of multiple lymphomatous polyposis of the gastrointestinal tract. Both patients had multiple polypoidal defects involving large segments of gastrointestinal tract. The histopathology in both cases was diffuse poorly differentiated lymphoma. One case had multiple relapses despite treatment and died after 58 months. The second patient died following induction chemotherapy.

Adult↗
PubMed2001

In situ hybridization of Epstein-Barr virus in tumor cells and tumor-infiltrating lymphocytes of the gastrointestinal tract.

Unlike gastric carcinoma, associations of the Epstein-Barr virus (EBV) with carcinomas of other sites in the gastrointestinal tract have not yet been clarified. To elucidate these associations, we investigated the presence of EBV in 142 cases of esophageal carcinoma, 107 cases of ampulla of Vater carcinoma, and 274 cases of colorectal carcinoma in Korean patients using EBV-encoded small RNAs (EBER)-in situ hybridization (ISH). In all cases, none of the tumor cells showed a positive signal, indicating that EBV is not generally related to the carcinogenesis of these cancers. Some EBV-positive tumor-infiltrating lymphocytes (TILs) were found in 8 of 142 cases (5.6%) of esophageal carcinoma, 8 of 107 cases (7.5%) of ampulla of Vater cancer, and 35 of 274 cases (12.8%) of colorectal carcinoma. For comparison, EBER-ISH was performed in consecutive gastric carcinomas; the EBER signal on tumor cells was observed in 17 of 306 cases (5.6%), and EBV-positive TILs were seen in 31 of the 289 cases (10.7%). There was no statistically significant difference in the frequencies of cases with EBV-positive TILs among the gastrointestinal tract cancers. We suggest that the reservoir lymphocytes carrying EBV, like other inflammatory cells, are able to reach anywhere, and that the chance for an epithelial cell to be exposed to EBV is similar at different sites of the gastrointestinal tract, regardless of its carcinogenic effect on the epithelial cell. HUM PATHOL 32:297-301.

Adenocarcinoma↗
PubMed2006

[Evaluation of FDG-PET imaging for the detection of gastrointestinal tract cancer in patients with suspected lung cancer].

This study evaluated 18F-FDG-PET imaging for the detection of gastrointestinal tract cancer in patients with suspected lung cancer. A total of 351 patients who had abnormal lung shadows and who underwent whole-body FDG-PET between June 1998 and January 2006 were retrospectively entered for analysis. Gastrointestinal tract cancers were subsequently found in 15 patients (4.3%) who had been found to have lung diseases consisting of 7 inflammatory changes, 6 lung cancers, and 2 metastatic lung carcinomas, 9 colon cancers, 4 gastric cancers, and 2 esophageal cancers. Five patients (2 colon cancers, 2 gastric cancers, and 1 esophageal cancer) had early stage carcinoma. In this study, FDG-PET was useful not only for the diagnosis and staging of lung cancer, but also for the detection of unexpected gastrointestinal tract cancers. FDG-PET may be most suitable for cancer screening.

Aged↗
PubMed1993

Contrast enhancement of the gastrointestinal tract on MR images using intravenous gadolinium-DTPA.

Gadopentetate dimeglumine was administered intravenously to 16 patients undergoing abdominal magnetic resonance (MR) imaging. T1-weighted and fat-suppressed T1-weighted images were acquired before and after intravenous administration of 0.1 mmol/kg gadopentetate dimeglumine. The stomach, small bowel, and colon were analyzed regarding the presence and relative intensity of contrast enhancement. Diffuse enhancement of the gastrointestinal tract wall was observed in all patients following contrast material administration. Such enhancement was most conspicuous on fat-suppressed T1-weighted images. Quantitative measurements indicated that the wall of the gastrointestinal tract enhanced approximately 100% with gadopentetate dimeglumine. This study demonstrates that enhancement of the normal gastrointestinal tract occurs routinely when intravenous gadopentetate dimeglumine is administered, and such enhancement should not be considered indicative of gastrointestinal pathology. Furthermore, it suggests the potential utility for using intravenous rather than orally administered contrast agents to provide enhancement of the gastrointestinal tract on MR images.

Adult↗
PubMed1996

Biomechanics of the gastrointestinal tract.

As the function of the gastrointestinal tract is to a large degree mechanical, it has become increasingly popular to acquire distensibility data in motility research based on various parameters. Hence it is important to know on which geometrical and mechanical assumptions the various parameters are based. Currently, compliance and tone derived from pressure-volume curves are by far the most often used parameters. However, pressure-volume relations obtained in tubular organs must be carefully interpreted as they provide no direct measure of luminal cross-sectional area and other variables useful in plane stress and strain analysis. Thus, erroneous conclusions concerning tissue distensibility may be deduced. Other parameters, such as wall tension, stress and strain, give more useful information about mechanical behaviour. Distensibility data procure significance in fluid mechanics and in the study of tone, peristaltic reflexes, and mechanoreceptor kinematics. Such data are needed for the determination of the interaction between stimulus, electrical responses in neurons and the mechanical behaviour of the gut. Furthermore, from a clinical perspective, investigation of visco-elastic properties is important because GI diseases are associated with growth and remodelling. For example, prestenotic dilatation, increased collagen synthesis, dysmotility and altered distensibility are common features of obstructive diseases. The purpose of this review is to discuss the physiological and clinical importance of acquiring biomechanical data, distensibility parameters and interpretation of these results and their associated errors. We will also discuss some aspects of the relationship between morphology, growth and biomechanics. Finally, we will outline a number of techniques to study the mechanical properties of the GI tract.

Biomechanical Phenomena↗
PubMed1998

Systemic amyloidosis and the gastrointestinal tract.

Systemic amyloidosis is caused by a variety of different diseases and frequently involves the gastrointestinal tract. Each type of amyloid affects the gastrointestinal tract differently. This article reviews the unique pathogenesis, pattern of gastrointestinal disposition, diagnosis, and treatment of the five systemic amyloidoses, and discusses the gastrointestinal diseases that cause systemic amyloidosis: inflammatory bowel disease and familial Mediterranean fever.

Amyloidosis↗
PubMed2002

[Treatment of acute ulcerations of the upper part of the gastrointestinal tract in patient with a neuroreanimation profile].

A success in treatment of acute ulcerations of the upper parts of the gastrointestinal tract in patients with a severe neurosurgical pathology can be achieved only with a complex approach to treatment of the intensive care patients. The application of antiulcerous medicines in combination with pyrokinetics and medicines improving the regeneratory ability of the gastrointestinal tract mucosa allowed to considerably decrease risk of the development of gastroduodenal bleedings against the background of erosive-ulcerous lesion of the mucosa. The endoscopic methods of arresting bleedings in such patients in combination with the correction of homeostasis by infusions and local hemostatic therapy in most cases result in reliable hemostasis of the upper parts of the gastrointestinal tract. The program of active measures is completed with the early enteral feeding with balanced nutritional mixtures.

Acute Disease↗
PubMed1996

Zinc uptake in five sectors of the rat gastrointestinal tract: kinetic study in the whole colon.

PURPOSE: The uptake of zinc as acexamic acid salt in the rat gastrointestinal tract, using an in situ static technique, was studied. Our aim was to investigate an absorption window for zinc and the uptake kinetics in the colon. METHODS: To detect selectivity phenomena in zinc absorption, buffered saline solutions of zinc (50 micrograms/ ml) were perfused in stomach, whole colon and three 33-cm fractions of the small intestine (proximal, middle and distal segments). To characterize zinc uptake kinetics in whole colon, five different zinc concentrations (5, 25, 50, 150 y 250 micrograms/ml) were assayed. Zinc secreted into the gastrointestinal tract during the experiments was deducted from the uptake. RESULTS: Zinc secretion was characterized as an apparent zero-order process for all the studied segments (mean secretion rate = 0.10 +/- 0.03 microgram/(ml x min)). The stomach exhibited little ability to absorb zinc (apparent first order rate constant = 0.17 +/- 0.07 h-1), whereas the highest transport rates were found in the last two thirds of the small intestine and colon (first order constants: 0.66 +/- 0.13 h-1, 1.00 +/- 0.06 h-1, 0.97 +/- 0.14 h-1, 0.96 +/- 0.19 h-1 for proximal, middle, distal and colon segments, respectively). Zinc uptake in the colon was characterized by means of a Michaelis-Menten and first-order combined kinetics, with the following parameters: Vm = 0.36 +/- 0.02 microgram/(ml x min), Km = 18.01 +/- 0.40 microgram /ml and Ka = 0.40 +/- 0.01 h-1. CONCLUSIONS: Zinc is preferably absorbed in the middle and distal parts of the rat gastrointestinal tract. In the colon a saturable mechanism may be involved in apparent absorption.

Aminocaproates↗
PubMedDate not supplied

Melatonin and its receptors in the gastrointestinal tract.

Melatonin and its synthesizing enzymes have been demonstrated in the gastrointestinal tract, suggesting the in situ biosynthesis of melatonin by the gut tissues. There appears to be a diurnal rhythm of melatonin in the gastrointestinal tissues of birds and rodents, with high levels in the dark period. Release of gut melatonin into the general circulation, however, was recorded following tryptophan treatment. Melatonin has direct gastrointestinal functions: it decreased serotonin-induced gut concentration, alleviated serotonin-induced reduction in gastric glandular mucosal blood flow, diminished epithelial sodium absorption, and inhibited the proliferation of jejunal epithelium. The use of a radiolabeled melatonin agonist, 2-[125I]iodomelatonin, has allowed the study of putative melatonin receptors in the gut of duck, mouse, chicken and human. The gastrointestinal 2-[125I]iodomelatonin binding to the duck, chicken and human was rapid, stable, saturable, reversible, specific and with a high affinity. The 2-[125I]iodomelatonin binding sites in the mouse gut were of a much lower affinity. In the duck gut, there was a significant variation in the densities of 2-[125I]iodomelatonin binding sites in different regions of the gut, with the following descending order of density: ileum, jejunum > duodenum, colon > cecum > esophagus. Autoradiographical studies have showed that the highest concentration of 2-[125I]iodomelatonin binding sites was in the villi of the small intestine and also in the mucosal layers of the cecum and colon. In contrast to the diurnal rhythms of 2-[125I]iodomelatonin binding sites reported in other tissues, 2-[125I]iodomelatonin binding in the duck gut showed no daily rhythm. The subcellular distribution of binding sites was in the following descending order: nuclear > microsomal > mitochondrial >> cytosolic fraction. These findings are consistent with a paracrine and/or hormonal action of melatonin in the gastrointestinal tract.

Animals↗
PubMed1999

Outcome and cost-effectiveness of perioperative enteral immunonutrition in patients undergoing elective upper gastrointestinal tract surgery: a prospective randomized study.

HYPOTHESIS: Perioperatively administered enteral immunonutrition will improve early postoperative morbidity and cost-effectiveness after gastrointestinal tract surgery. DESIGN: A prospective, randomized, double-blind, multicenter clinical trial. SETTING: Surgical departments in German university and teaching hospitals. PATIENTS: One hundred fifty-four patients with upper gastrointestinal tract malignant neoplasms who were eligible for analysis. INTERVENTION: Preoperatively, patients received 5 days of oral immunonutrition (an arginine-, RNA-, and omega3 fatty acid-supplemented diet) or an isoenergetic control diet (1 L/d). Early postoperative enteral feeding with immunonutrition or an isoenergetic, isonitrogenous control diet using a catheter jejunostomy was performed for 10 days. MAIN OUTCOME MEASURES: Postoperative infectious complications, their treatment costs, and cost-effectiveness of immunonutrition were analyzed. Plasma levels of the fatty acids eicosapentaenoic acid and docosahexaenoic acid were measured. RESULTS: In the immunonutrition group, significantly fewer infectious complication events occurred (14 vs 27; P = .05). The number of patients with complications was significantly lower in the supplemented diet group after postoperative day 3 (7 vs 16; P = .04). The treatment costs of complications in the supplemented diet group were suggestively lower than in the control diet group (DM 75172 vs DM 204273). Cost-effectiveness was DM 1503 in the experimental group vs DM 3587 in the control group, where DM denotes deutsche mark (German currency). CONCLUSION: The perioperative administration of an enteral immunonutrition significantly (P = .05) decreased the early occurrence of postoperative infections and reduced substantially the treatment costs of the complications after major upper gastrointestinal tract surgery.

Adjuvants, Immunologic↗
PubMed2005

Endoscopic mucosal resection for early cancers of the upper gastrointestinal tract.

The purpose of this literature review is to examine recent advances in technique and technology of endoscopic mucosal resection of superficial early cancers of the upper gastrointestinal tract. Endoscopic mucosal resection (EMR) of superficial early cancers of the upper gastrointestinal tract is standard technique in Japan and is increasingly used in Western countries. Newer techniques of EMR allow removal of larger lesions en-bloc. These minimally invasive techniques, when applied correctly, allow safe and efficacious treatment in situations that would otherwise require major surgery. Through the establishment of long-term outcomes data, standardization of endoscopic and pathologic reporting, and newer EMR technology and techniques, the future treatment of early cancers in the upper gastrointestinal tract may be achieved primarily through the endoscope.

Endoscopy, Gastrointestinal↗
PubMed1988

Distribution and ontogeny of glucagon-like cells in the gastrointestinal tract of the cartilaginous fish Scyliorhinus stellaris (L.).

The ontogeny and distribution of glucagon-like cells were studied in the gastrointestinal tract of embryos, neonates, and adults of the cartilaginous fish Scyliorhinus stellaris (L.) by immunocytochemistry. The results indicate that they appear early during embryonic development, and, in some portion of the gastrointestinal tract, even before the mucosa morphological differentiation. Immunoreactive glucagon-like cells were observed both in gastric and intestinal epithelium, being present in the pyloric portion only at a particular period of its differentiation. Some differences were observed between the embryonic and adult distributive pattern. They were more numerous in proliferative zone and sometimes were situated near other endocrine epithelial cells. These findings together with available information on trophic effects of some gastrointestinal hormonal peptides suggest a possible regulatory role of this peptide on the growth and differentiation of the gastrointestinal tract.

Animals↗
PubMed1991

Carcinoid tumour of the gastrointestinal tract: prognostic factors and disease outcome.

This study represents retrospective analysis of 87 patients with a carcinoid tumour of the gastrointestinal tract seen and followed in the British Columbia Cancer Agency (BCCA) from 1960 to 1986. In 49 cases, the primary site was the small bowel. The rest of the cases were distributed as follows: 11 appendix, 10 rectum, 5 stomach, and 7 undetermined. We extrapolated the Dukes' and modified Astler-Coller surgicopathological classifications used for colorectal cancer for use in our cases of carcinoid tumour of the gastrointestinal tract. A strong correlation was found, using this staging, with disease-specific survival. Other prognostic factors included histologic differentiation, the presence of macroscopic residual disease after initial surgery, and level of 5-hydroxyindoleacetic acid (5-HIAA) in urine. Among 51 patients with surgically grossly removed disease, there was a tendency for the development of distant and distant/locoregional recurrence more often than locoregional recurrence alone. The liver was the commonest site of distant recurrence. Analysis of the effect of radiotherapy or chemotherapy on carcinoid tumour of the gastrointestinal tract proved unsuccessful because only a small portion of the patients had this treatment, and it was used mainly for palliation.

Adult↗
PubMed1992

Beta-adrenergic responsiveness of the gastrointestinal tract in diabetic rats.

Recently, decreased gastrointestinal beta-adrenergic responses in experimental diabetes have been demonstrated. Gastrointestinal responses to beta-adrenoceptor agonists are impaired in both insulin-dependent and non-insulin-dependent diabetic rat. Insulin treatment improves the impaired gastrointestinal beta-adrenergic responsiveness of diabetic rats. The improvement seen with insulin treatment on beta-adrenergic responsiveness is closely related to protein biosynthesis. The decreased beta-adrenergic responses in diabetic rat gastrointestinal tract seem to result from a decrease in the number of beta-adrenoceptors. It is most likely that the decreased gastrointestinal beta-adrenergic responsiveness is related to an impairment in the turnover of beta-adrenoceptors as a consequence of diabetes and that insulin has a beneficial effect on the impaired receptor turnover.

Adrenergic beta-Agonists↗