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PubMed1982

[New stage in the study of the central effects on digestive system functions].

The review included author's own studies and emphasizes the problem of peptides participating in transmission of central influences to the intramural nervous system in the digestive tract's organs, to their endocrine cells or directly to the secretory (or smooth muscle) cells. The role of endocrine apparatus of the digestive tract's organs is discussed as well as the role of the so called peptidergic fibers of the vegetative nervous system in regulation of secretory function of the stomach and pancreas.

Animals↗
PubMed1993

Expression of growth factor peptides and their receptors in neuroendocrine tumors of the digestive system.

Neuroendocrine tumors of the digestive system are slow growing neoplasms which often present with pronounced fibrosis around tumor cells and in the peritoneal cavity. In this report 30 midgut carcinoids and endocrine pancreatic tumors were examined for the expression of peptide growth factors and their receptors, both by immunohistochemistry and in situ hybridization. Our data indicate that multiple peptide growth factors, PDGF, TGF-beta, and bFGF are expressed by these tumors. PDGF was expressed on tumor cells and stroma in 70% of tissues examined. PDGF alpha-receptor was seen on clusters of tumor cells and occasionally on adjacent stroma, whereas PDGF beta-receptor was seen only in the stroma. Our data suggest that PDGF may be involved in the autocrine stimulation of tumor cells and stimulation of stromal cell growth through paracrine and possibly autocrine mechanism. In addition, tumor tissues express all three isoforms of TGF-beta in more than half of the tissues examined. Tumor cells produce small latent complexes causing an escape from potent inhibitory effect of TGF-beta and stimulation of stromal cell growth and matrix deposition through paracrine mechanism. bFGF, a potent stimulant of endothelial cell growth, was expressed by all tumor tissues examined. Our data suggest that multiple peptide growth factors may have an important role in tumor progression and desmoplastic reaction accompanying these tumors.

Adenoma, Islet Cell↗
PubMedDate not supplied

Expression of transforming growth factors beta 1, beta 2, beta 3 in neuroendocrine tumors of the digestive system.

Neuroendocrine tumors of the digestive system are slowly growing neoplasms which often present pronounced fibrosis around tumor cells and in the peritoneal cavity. In this study, 23 midgut carcinoids and 7 endocrine pancreatic tumors were examined for the presence of TGF-beta with affinity-purified polyclonal antibodies raised against synthetic peptides coding for a specific region of latency-associated peptide sequences of TGF-beta 1, -beta 2, -beta 3, a rabbit anti serum against TGF-beta binding protein (LTBP) and a rabbit polyclonal antibody against TGF-beta type II-receptor (TGF-beta RII). Tumor cells from most tissues expressed all three isoforms of TGF-beta but LTBP was only weakly expressed. In stromal cells abundant expression of TGF-beta 2 and LTBP was found, whereas TGF-beta 1 and TGF-beta 3 were expressed only weakly. TGF beta RII immunoreactivity was observed mostly in the stromal cells. Tissue sections from 4 of these neuroendocrine tumors were also investigated by in situ hybridization. Strong signals on tumor cells were detected with TGF-beta 2 and TGF-beta 3 cRNA probes and also weakly with TGF-beta 1 and LTBP cRNA probe. Strong positive signals were observed on stromal cells with TGF-beta 2 and LTBP probe whereas only weak signals were observed on the stromal cells with TGF-beta 3 probe. Strong signals were detected on stromal cells with TGF-beta RII probe whereas no signals were observed on tumor cells. Our data suggest that TGF-beta might play an important role in the interaction of tumor and stromal cells. Thus TGF-beta might stimulate matrix production and angiogenesis of stromal cells, whereas tumor cells themselves are unaffected by the growth inhibitory activity of TGF-beta.

Adenoma, Islet Cell↗
PubMed2003

Cholesterol crystal embolization to the digestive system: characterization of a common, yet overlooked presentation of atheroembolism.

In the 1359 published patients with multiorgan cholesterol crystal embolism (CCE), the digestive system seems to be the third most frequently affected system. Yet, this system received hitherto only little attention in the medical literature. Therefore, the aim of the present study was to clinically characterize the subset of patients with CCE involving the digestive system, based on our institutional experience and a review of the literature. Cases with CCE in a 7-yr period (1995-2001) were sought in the computerized records of our medical center. Of the CCE patients, those with digestive system involvement that could be related to CCE were included in this study. The clinical features of CCE were determined and compared with those found in published series. Fourteen cases with CCE were identified, giving an annual incidence of 0.8 per 10(5). Digestive system involvement was found in five (36%) of the 14 patients. All five patients had established atherosclerosis. Precipitating factors were vascular manipulations or anticoagulation treatment in four of these five patients. Two patterns of disease appeared: acute catastrophic multiorgan disorder with poor prognosis and chronic and more indolent GI disease. Abdominal pain, GI bleeding, fever, and diarrhea were the most common manifestations, resulting from bowel infarction, mucosal ulcerations, hepatocellular liver disorder, and/or pancreatitis. CCE is a systemic disorder with a frequent involvement of the digestive system and protean clinical manifestations. It should, therefore, be considered in any gastroenterological patient with atherosclerosis and recent vascular manipulations or systemic anticoagulation.

Aged↗
PubMed1990

Environmental diseases of the digestive system.

Environmental factors are important mediators of many diseases of the digestive system, defined as the alimentary tract and the accessory organs of digestion, the liver and pancreas. In this review, we principally focus on the action of chemical agents which are classified as (1) naturally occurring compounds, (2) occupational hazards, (3) therapeutic drugs, and (4) constituents of substances of abuse. In addition, the putative role of dietary habits in the pathogenesis of malignant diseases of the digestive system is discussed.

Alcohol Drinking↗
PubMed1996

[Evaluation of the effectiveness of screening for tumors of the digestive system].

Some features of digestive cancers encourage screening programs, even though no such program has been shown so far effective in reducing mortality rates. The visual inspection of the oral cavity and pharynx, with the addition of flexible endoscopy and, possibly, blue-toluidine staining, can be easily performed by specialists and dentists. The strong association with smoking habits and alcohol consumption favours the organization of screening programs but primary prevention maintains the highest priority. For cancer of the colon-rectum two different screening approaches are under close scrutiny: fecal occult blood testing, on an yearly basis, and once-in-a-life sigmoidoscopy at 55-60 years of age. Only one of five ongoing randomized prospective studies on occult blood testing has reported, so far, a significant reduction, around 33%, of mortality from colorectal cancer, with, however, a large burden of sigmoidoscopies.

Colorectal Neoplasms↗
PubMed1965

Specific carcinoembryonic antigens of the human digestive system.

A wide variety of human adult and fetal tissues were studied by immune-diffusion techniques in agar gel to determine whether they contained the tumor-specific antigen(s) previously found in coionic cancers. In the adult tissues it was demonstrated that identical antigens were present in all tested specimens of malignant tumors of the entodermally derived epithelium of the gastrointestinal tract and pancreas, but were absent from all other tested adult tissues. The common antigenic constituents, therefore, represent system-specific cancer antigens of the human digestive system. System-specific cancer antigens have not previously been demonstrated in humans. Experiments with fetal tissues demonstrated that identical antigens were also present in fetal gut, liver, and pancreas between 2 and 6 months of gestation. These components were named "carcinoembryonic" antigens of the human digestive system. On the basis of the present findings and the recent work regarding control of the expression of genetic potentialities in various types of cells, it was concluded that the carcinoembryonic antigens represent cellular constituents which are repressed during the course of differentiation of the normal digestive system epithelium and reappear in the corresponding malignant cells by a process of derepressive-dedifferentiation.

Antigens↗
PubMed1968

Physicochemical studies of the carcinoembryonic antigens of the human digestive system.

A procedure has been described for the purification of the carcinoembryonic antigens (CEA) of the human digestive system. Tumor tissue extraction in 0.6 M perchloric acid followed by paper block electrophoresis and column chromatography on Sephadex G-200 resulted in highly purified CEA preparations as determined by both immunological and physicochemical criteria. The properties and composition of five different purified CEA preparations derived from digestive system cancer metastases were examined. The findings demonstrated a high degree of uniformity amongst these samples. Sedimentation coefficients ranged from 6.9 to 8S. Each sample showed the presence of 14 different amino acid residues and six different carbohydrate constituents (four of which could be quantitated with the amount of material available for analyis). Studies of a purified CEA preparation from a primary hepatoma yielded results which, in some respects, differed from those obtained with the CEA samples of metastatic tumor origin. The implications of these variations were discussed with regard to the probable presence of non-CEA components in the hepatoma preparation. Of primary importance was the observation that the few normal adult digestive system tissues tested failed to show the presence of constituents similar to the CEA. This finding would seem to indicate that, in the adult, the carcinoembryonic antigens of the human digestive system are qualitatively tumor-specific and are not dectectable in comparable normal tissues.

Amino Acids↗
PubMedDate not supplied

The digestive system: linking theory and practice.

This article, the second in the nutrition series, presents an outline of food chemistry and the digestion of energy-producing foods. It is hoped that this will facilitate understanding of some of the principles of nutrition. A number of 'clinical points' are highlighted to emphasize the link between theory and practice. The processes by which the chemical building blocks (carbon, oxygen, hydrogen and nitrogen) are formed into more complex molecules such as proteins, carbohydrates and fats are explained. The gross anatomy of the digestive system is outlined and the sites where digestive enzymes are secreted are identified. Regulation of the digestive system by endocrine secretions and the nervous system is described and tabulated.

Carbohydrate Metabolism↗
PubMedDate not supplied

[A comparative evaluation of the action of kvamatel and omez on the glutathione system in different sections of the digestive system in experimental duodenal ulcer].

Experiments on male albino rats demonstrated significant changes in the content of oxidized and reduced glutathione in the tissues of the liver, pancreas, stomach, duodenum, and small intestine in acetate ulcer of the duodenum. Experimental therapy with quamatel and particularly with omez led to activation of the glutathione system in the tissues under and in this way increased their resistance to the ulcerogenic effect.

Animals↗
PubMed1996

[Analysis of mortality by population groups migrating within the country. Tumors of the digestive system].

This paper analyzes mortality of digestive system cancers in Italy during the years 1981-84 by groups of people migrated inside the country. Individuals born and died in the same region are defined as "stables". "Migrants" indicate individuals for which the region of birth differ from that of residence. Mortality for cancers of oral cavity and pharynx, and of the oesophagus, shows a negative effect of being born in the high risk regions of the north-east and a protective effect of being born in the low mortality regions of the south. Leaving high risk areas brings a positive effect, while to settle there makes mortality getting worse. For stomach cancer, the birth effect is very strong: in this first generation of migrants mortality rates are very similar to those of the stable in the birth areas. A strong migration effect is observed for colorectal cancer mortality: age specific mortality rates in migrants fit well those of host stable population. Liver cancer mortality of migrants from high risk areas approaches the one of the host population. Pancreatic cancer mortality shows a protective effect of being born in the south and a negative effect of residing in the northern high mortality areas.

Adolescent↗
PubMed1995

Early transition of the digestive system to exogenous nutrition in domestic post-hatch birds.

The effect of early transition of the digestive system to exogenous nutrition was examined in three experiments with growing birds. A nutrient mixture (0.5 ml) of glucose, starch and oil (1:1:0.5, by vol) was orally administered immediately after hatch to turkey poults (Meleagris gallopavo) having immediate or delayed access to feed (Expt 1). Increasing amounts (0, 0.25 and 0.5 ml) of this mixture were administered immediately after hatch to turkey poults (Expt 2), or to broiler chicks (Gallus domesticus; Expt 3). The relative weights of the gastrointestinal tract (GIT) and its ingesta content, and the amylolytic capability of the pancreas were examined during the immediate post-hatch period (to 30 h). Oral administration of nutrients immediately after hatching only slightly influenced the growth of the pancreas and its amylolytic activity, but significantly increased GIT weight in both species, in a dose-dependent manner. It is suggested that early post-hatching exposure of the digestive system by the forced administration of nutrient mixture induces anatomical and metabolic changes in the digestive system slightly earlier than in birds with late access to feed. This increases GIT content and plasma glucose levels, resulting in enhanced feed consumption and growth promotion.

Animals↗
PubMed1985

Determination and significance of a new carbohydrate antigen CA19-9 in digestive system cancers.

To assess the diagnostic significance of CA19-9, the serum levels in 225 healthy subjects, 201 patients with cancers, 423 patients with benign diseases and 21 pregnant women, were determined by RIA. The mean CA19-9 level of the healthy subjects was 11.2 +/- 0.4 U/ml (range, 6-100 U/ml). Only 3.1% of them were above 37 U/ml. The CA19-9 levels were elevated above 37 U/ml in 7.9% of 293 patients with non-carcinomatous diseases of the digestive system. Among digestive system cancers, elevated levels were found in 18.2% of 11 patients with esophageal cancer, 42.7% of 68 patients with gastric cancer, 39.1% of 23 patients with colorectal cancer, 27.8% of 18 patients with primary hepatic cancer, 71.4% of 35 patients with biliary cancer, and 75% of 20 patients with pancreatic cancer. Most of the patients with levels above 100 U/ml had carcinomatous diseases. The CA19-9 positive rates for patients with gastric cancer and colorectal cancer were extremely low at stages I, II and III, while in patients at stage IV and in patients with recurrent cancer, a tendency for rapid increase in the positive rates and concentrations of CA19-9 was noted. Based on combination assay of CA19-9, CEA and ferritin, in comparison with the positive rates for CA19-9 alone, it was found that the rates were raised to 42.7% in gastric cancer, to 39.1% in colorectal cancer, and to 71.4% in biliary cancer, suggesting the simultaneous determination with these tumor markers may serve to elevate their usefulness.

Adolescent↗