Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Digestive System”

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 271 records · Page 15Linked to original sources

[Acid base balance in the digestive system].

The mechanisms of acid base balance in digestive organs, including stomach, intestine as well as liver, have been described in the present paper. The stomach secrets large amount of acid as well as sodium bicarbonate, so that hydrogen ion would be lost in the severe vomiting state such as pyloric stenosis, resulting in metabolic alkalosis and hypokalemia. In the diarrheal condition, sodium bicarbonate would be lost in large amount, causing metabolic acidosis and hypokalemia. Hepatic failure induces the respiratory alkalosis of which mechanisms have not been clarified yet. In any case, urgent correction of acid base imbalnce would be crucial. It is, however, obscure to date how the systemic acid base imbalnce affects the function of the digestive system. This issue would be promising field in the investigation of digestive diseases.

Acid-Base Imbalance↗

Immunolocalization of the water channel, aquaporin-5 (AQP5), in the rat digestive system.

Aquaporin-5 (AQP5), an isoform of membrane water channel aquaporins, is expressed in the salivary and lacrimal glands. We surveyed the expression and immunohistochemical localization of AQP5 in the rat digestive system. RT-PCR analysis revealed that AQP5 is expressed in the submandibular gland, tongue, gastric corpus, pyloric region, duodenum, and liver. Immunofluorescence microscopy using AQP5-specific antibodies showed that AQP5 protein is present in the minor salivary glands of the tongue, the pyloric glands, and duodenal glands. To distinguish apical and basolateral domains of the plasma membrane of epithelial cells, double-immunofluorescence staining for AQP5 and tight junction protein occludin was performed. In the minor salivary gland, AQP5 was present in both the serous and mixed secretory end portions. AQP5 was found in the apical membrane of the secretory cells including intercellular secretory canaliculi demarcated with occludin. At higher magnifications, omega-shaped indentations of AQP5 labeling were seen along the apical membrane, suggesting a dynamic process for the apical membrane in exocytosis. Only weak labeling for AQP5 was detected in the basolateral domain. In the stomach, AQP5 was detected in the apical membrane of the pyloric gland secretory cells. In the duodenum, AQP5 was restricted to duodenal glands, where it was localized to the apical membrane. AQP5 was not detected in the intestinal glands or cells in the villi. These observations show that AQP5 is localized mainly in the apical membrane, including intercellular secretory canaliculi of secretory cells in the minor salivary glands, pyloric glands, and duodenal glands. AQP5 appears to play an important role in water transfer in these glands.

Animals↗

Histopathological and enzymological studies on the effects of chronic lead nitrate intoxication in the digestive system of a freshwater teleost, Channa punctatus.

The effect of lead nitrate on the digestive system of a teleost fish, Channa punctatus has been studied after 125 days of exposure to a sublethal concentration (6.8 mg/liter). The results show that considerable degenerative changes are produced in the histological structure of liver, intestine, and pyloric caeca. In the liver, the damage is in the form of liver cord disarray, necrosis, inflammation of portal areas, hardening of connective tissue, shrinkage of nuclei, and septa formation around blood vessels. No fatty infiltration or glycogen depletion has been observed. Lipofuscin granules accumulated in the cytoplasm of hepatocytes. In the intestine and pyloric caeca flattening of villi at a number of places, inflammation, and necrosis are the most conspicuous changes. The activities of alkaline phosphatase and aminotripeptidase are inhibited in the liver. In stomach, alkaline phosphatase is inhibited but an elevation in amylase activity was noted. Acid phosphatase showed an increase in the intestine and pyloric caeca while aminotripeptidase and glycylglycine dipeptidase were inhibited.

Aminopeptidases↗

Severe acute respiratory syndrome and its lesions in digestive system.

Severe acute respiratory syndrome (SARS) is an infectious atypical pneumonia that has recently been recognized in the patients in 32 countries and regions. This brief review summarizes some of the initial etiologic findings, pathological description, and its lesions of digestive system caused by SARS virus. It is an attempt to draw gastroenterologists and hepatologists' attention to this fatal illness, especially when it manifests itself initially as digestive symptoms.

Digestive System↗

Economic status and survivorship in digestive system cancers.

This study investigates economic differentials in cancer survival in a sample of 1180 white men, focusing in particular on the relationship between income level and survivorship in the various subsites comprising the digestive system cancer category. Using the Cox proportional hazards model to control for confounding variables, the economic status-survivorship relationship is estimated for several subgroupings of primary malignancies. The results show significant variation in this relationship across different cancer sites, with a pronounced effect observed in carcinomas of the small intestine, peritoneum and, especially, colon and rectum. High-income patients with these malignancies had a significantly lower risk of dying from the disease (P less than 0.05) than either their middle- or lower-income counterparts, controlling for age, stage, and initial course of treatment. Differences in immunologic status, tumor characteristics, and follow-up treatment may account for these economic effects.

Age Factors↗

New approach to control the methanogenic reactor of a two-phase anaerobic digestion system.

A new control strategy for the methanogenic reactor of a two-phase anaerobic digestion system has been developed and successfully tested on the laboratory scale. The control strategy serves the purpose to detect inhibitory effects and to achieve good conversion. The concept is based on the idea that volatile fatty acids (VFA) can be measured in the influent of the methanogenic reactor by means of titration. Thus, information on the output (methane production) and input of the methanogenic reactor is available, and a (carbon) mass balance can be obtained. The control algorithm comprises a proportional/integral structure with the ratio of (a) the methane production rate measured online and (b) a maximum methane production rate expected (derived from the stoichiometry) as a control variable. The manipulated variable is the volumetric feed rate. Results are shown for an experiment with VFA (feed) concentration ramps and for experiments with sodium chloride as inhibitor.

Algorithms↗