Gastrointestinal microorganisms

C. S. Stewart, m Ecology and Physiology of Gastrointestinal Microorganisms,cds. R. I. Mackieand... 

R. R. Scheline, Metabolism of foreign compounds by gastrointestinal microorganisms, Pharmacol, Rev., 25,... 

On the other hand, there are reports that marijuana use is associated with compromised health status among HIV-infected individuals. Lozada et al. (1983) assessed oral manifestations of tumor and opportunistic infections in 53 AIDS-affected men with Kaposi s sarcoma (KS). Twenty-seven had biopsy-proved oral KS, the palate being the most common site. Past or present infections with cytomegalovirus, hepatitis, venereal diseases, and gastrointestinal microorganisms occurred in more than 70%. Oral candidiasis was confirmed in 57%. Heavy marijuana smoking was identified as the most common habit among these individuals. Newell et al. (1985) reported that marijuana use was a risk factor... 

This occurs in the seromucous secretions such as saliva, tears, nasal secretions, sweat, colostrum and secretions of the lung, urinogenital and gastrointestinal tracts. Its purpose appears to be to protect the external surfaces of the body from microbial attack. It occurs as a dimer in these secretions but as a monomer in human plasma, where its function is not known. The function of IgA appears to be to prevent the adherence of microorganisms to the surface ofmucosal cells thus preventing them entering the body tissues. It is protected from proteolysis by combination with another protein—the secretory component. 

The gastrointestinal microflora provide another potential site for drug metabolism within the GIT, and it has received some attention. In normal subjects the stomach and proximal small intestine contain small numbers of microorganisms. Concentrations of these organisms increase toward the distal end of the intestine. A wide variety of aerobic and anaerobic organisms are present in the gut. The microflora, derived primarily... 

Molecular hydrogen is an important intermediate in the degradation of organic matter by microorganisms in anoxic habitats such as freshwater and marine sediments, wet land soils, and the gastrointestinal tract of animals. In these particular conditions H2 is produced during fermentation of carbohydrates, lipids, nucleic acids, and proteins by anaerobic bacteria and,... 

Caution A toxin is a poison produced by a living organism. The middle term of staphylococcal enterotoxin B means a toxin that is produced by microorganisms, such as some staphylococci, and causes gastrointestinal symptoms. 

Savage, D. C. (1984). Association of indigenous microorganisms with gastrointestinal epithelial surfaces. In "Human Intestinal Microflora in Health and Disease." (D. H. Hentges, ed.), pp. 55-78. Academic Press Inc., New York, NY. 

Clarithromycin is better absorbed and irritates the gastrointestinal tract less than erythromycin. It is presumed that its activity exceeds that of erythromycin by 2-4 times with respect to a number of streptococci and staphylococci, and to a few other microorganisms. It is used for treating bacterial bronchitis, pneumonia, skin and sexual infections. It is believed that clarithromycin is the most active macrolide for treating atypical mycobacteria. Synonyms of this drug are biaxin and others. 

It is used for various gastrointestinal diseases caused by microorganisms sensitive to it, including enteritis, which is caused by microbes that are resistant to antibiotics. However, because of its high oto- and nephrotoxicity, its local use is preferred for infected skin diseases, infected wounds, conjunctivitis, keratitis, and others. Synonyms of this drug are framycetin, soframycin, tautomycin, and others. 

Ethionamide is active with respect to Mycobacterium tuberculosis and Mycobacterium leprae, but it does not have an effect on other microorganisms. It enhances phagocytosis at the center of tuberculous inflammation, which facilitates its decomposition. However, it frequently causes side effects associated with the gastrointestinal tract as well as a hepa-totoxic effect in approximately 5% of patients. Synonyms of this drug are trecatil, ethimide, thiomid, tuberin, tuberoid, and others. 

These antibiotics are partially absorbed from the stomach and upper gastrointestinal tract. Food impairs absorption of all tetracyclines except doxycycline and minocycline. Absorption of doxycycline and minocy-cbne is improved with food. Since the tetracyclines form insoluble chelates with calcium (such as are found in many antacids), magnesium, and other metal ions, their simultaneous administration with milk (calcium), magnesium hydroxide, aluminum hydroxide, or iron will interfere with absorption. Because some of the tetracyclines are not completely absorbed, any drug remaining in the intestine may inhibit sensitive intestinal microorganisms and alter the normal intestinal flora. 

Mechanism of Action A penicillin that acts as a bactericidal in susceptible microorganisms. Therapeutic Effect Inhibits bacterial cell wall synthesis. Bactericidal. Pharmacokinetics Poorly absorbed from gastrointestinal (GI) tract. Protein binding 87%-90%. Metabolized in liver. Primarily excreted in urine. Not removed by hemodialysis. Half-life 10.5-1 hr (half-life increased with imparted renal function). 

Inflammatory influences. Inflammation (p. 1211), which usually accompanies infection and can also arise from allergic responses, is affected by many substances.2293-6 These include chemotactic factors that attract neutrophils and monocytes2220 2294 and the adhesion molecules that assist in the movement of lymphocytes. 229e/f Some epithelial tissues, such as the mucosal surfaces of the gastrointestinal tract, are maintained in a continuous very low level of inflammation. This reflects the balance between activation of the immune system and inhibition of the system by signals from microorganisms both pathogenic and commensal 229 h... 

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