Gastrointestinal system stomach

Other forms of lead poisoning can also occur. For example, people who work in factories where lead is used can inhale lead fumes. The amount of fumes inhaled at any one time may be small. But over months or years, the lead in a person s body can build up. This type of lead poisoning can lead to nerve damage and problems with the gastrointestinal system (stomach and intestines). 

Gastrointestinal Effects. There were no histopathological effects on the stomach, small intestines, or large intestines with inhalation or oral exposure to hexachloroethane at any concentration tested (15-5,900 ppm for the inhalation route and 1-750 mg/kg/day for the oral route) and with acute, intermediate, or chronic exposure durations (Gorzinski et al. 1985 NTP 1977, 1989 Weeks et al. 1979). The risk that humans will experience adverse effects on the gastrointestinal system as the result of exposure to hexachloroethane in the environment seems to be relatively low. 

The gastrointestinal system of zebrafish presents clear differences from the human system. The zebrafish does not possess a stomach, the intestine is continuous with the pharynx through a short esophagus, and no sphincters are present [61]. However, zebrafish have most of the cell types observed in the small intestine -absorptive, endocrine, goblet, and interstitial cells of Cajal, although Paneth cells are absent. Gut contractions are under the control of the enteric nervous systems, which respond to different pharmaceuticals in similar way as the mammalian counterpart. For example, zebrafish embryos can be used as predictor of emetic response to pharmaceuticals, one of the most commonly reported clinical adverse effects to be considered in the development of new dmgs [61]. 

For the plant, another good way to stop consumption by an animal is to affect the animal s gastrointestinal system. This approach is used by a number of plants, but the mechanism of action varies. The first approach is direct irritation of the stomach lining to induce nausea and vomiting. The induction of mild vomiting is useful in some situations. The sacred bark of the California buckthorn produces cascara that is used to induce mild vomiting (a purgative). 

As mentioned above, the liver has a dual blood supply. The hepatic artery delivers material from the systemic circulation and the portal blood flow delivers directly from the gastrointestinal system. The portal system is involved in the first pass effect , where the nutrients and xenobiotics that are absorbed from the stomach and intestines are filtered through the liver before reaching the systemic circulation (Treinen-Moslen, 2001). The space of Disse allows close contact between circulating plasma, plasma proteins, and hepatocytes, allowing for rapid diffusion of lipophilic compounds across the hepatocyte membrane. Some compounds are specifically taken up by sinusoidal transporters, including... 

Cancer at Other Sites. Mortality studies of asbestos workers have revealed small increases in the incidence of death from cancer at one or more sites other than the lung, the pleura, or the peritoneirm, mostly in tissues of the gastrointestinal system. For example, a total of 99 deaths from cancers of the esophagus, stomach, colon, or rectum were observed in a cohort of 17,800 insulation workers, while only... 

When a drug is taken in solid form, as aspirin is, for example, its solubilitt depends on conditions at the site of absorption. For instance, aspirin is fairly insoluble in the acidic environment of the stomach, and this places a limit on its absorbability. This point relates to the importance of the environment in the gastrointestinal system and its influence on the absorjition of drugs that are taken oralh, as we have discussed. Circulation at the site of absorption also influences it, as more blood flow speeds absorption. Finally, the size of the absorbing surface makes a difference. Drugs arc absorbed more rapidly from larger surface areas. 

There are numerous reports on the biomedical effects of pectin. Antidiarrheic action is the most widely known property, and pectin has been used to treat diarrhea for more than half a century (Malyoth, 1934 Tompkins, 1938). This effect is often followed by an antivomitive action, which in babies improves assimilation and toleration, particularly of dairy products. This is a consequence of some protection and regulation of the gastrointestinal system (Pilnick and Zwicker, 1970). High-methoxyl pectins are often used to treat gastritis and ulcers. Because the stomach walls become covered with a gel-like film after swallowing pectin, a protective effect on the stomach from gastric and biliar hypersecretions occurs (Navarro and Navarro, 1985). 

Leukotriene Actions in the Gastrointestinal System - Large species differences have been found in the response of gastrointestinal tissue to sulfidcpeptide leukotrienes. Human gastrointestinal muscle (ileum, stonach, jejunum, colon) does not contract to SRS-A from guinea pig lung. In contrast, both LTC, and ITD contract the rat stomach and colon but not the duodenum or ileum. 4 dd E, produce... 

At some point, all of us have had a bellyache—especially right before an exam— that suddenly disappeared once the exam was over. However, a stomach ache and other ahments of the gastrointestinal system are not as easily cured by removing stress. Some require more sophisticated treatment with medication. 

Ear, nose and throat, endocrine and gastrointestinal systems The safety of ginkgo biloba extract was investigated in rats and mice as part of a U.S. National Toxicology Program [9. Animals were administered com oil extract with or without ginkgo biloba, at different doses, for up to 2 years. Ginkgo biloba induced liver and thyroid hypertrophy in rats and mice liver hyperplasia in rats hyperplasia and atrophy of the epithelium in the nose of rats and inflammation, hyperplasia and ulcer in the stomach of mice. Moreover, there was an increased incidence of thyroid cancer in rats and male mice, and liver cancer in mice [9 ]. 

In severe cases, or those refractory to treatment, truncal and limb weakness may be accompanied by involvement of masticatory, bulbar, and respiratory muscles. However the most life-threatening clinical manifestations are those affecting the gastrointestinal tract, since stomach ulceration can occur and death from perforation and peritonitis are not unknown. Medication with steroidal antiinflammatory agents is necessary but weakens the childrens resistance to infection, so that systemic spread of usually self-limiting disorders, such as candidiasis, may occasionally occur. 

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