Gastrointestinal systems

The principal nutrients of the body are of the same type as those that it uses as stores, namely, complex carbohydrates, triacylglycerol, and protein. These are hydrolyzed within the intestinal tract to produce primarily mono- and disaccharides, amino acids and small peptides, glycerol, and free fatty acids (Chapter 12). 

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In addition, the alkaloid colchicine (from Colchicum autumnale) blocks tubulin polymerization by binding to heterodimeric (3-tubulin between amino acids 239 and 254. Since it inhibits the MT-dependent migration of granulocytes into areas of inflammation and their MT-dependent release of proinflammatory agents, it is used to treat attacks of gout. Its antimitotic effect in the gastrointestinal system induces diarrhoea. Nocodazole competes for the binding site of colchicine and has similar effects on heterodimeric (3-tubulin. 

Q Constipation related to the effects of the narcotics on the gastrointestinal system... 

Gastrointestinal system—nausea, vomiting, increased appetite, weight gain, and peptic ulcer ... 

Goldenseal Hydrastis canadens s Antiseptic for skin (topical), astringent for mucous membranes (mouthwash), wash for inflamed eyes, sinus infections, peptic ulcers, colitis, gastritis Large doses may cause dry or irritated mucous membranes and injury to the gastrointestinal system may reduce the beneficial bacteria in the intestines. Siould not be taken for more than 3-7 days. 

Chapter 48 Drugs That Affect the Gastrointestinal System... 

Unit VIII lias been expanded to cover drugs that affect both the gastrointestinal and urinary systems. The unit consists of three chapters uretics, urinary anti-infectives and miscellaneous urinary drugp, and drag s that affect the gastrointestinal system. 

Meiss, R.A. (1989). Mechanics of gastrointestinal smooth muscle. In Handbook of Physiology, Section VI. The Gastrointestinal System, Volume 1, Part 1 (Wood, J.D. ed.), pp. 273-329, American, Physiological Society, Bethesda, MD. 

A further interesting phenotype identified in SDF-1/CXCR4 knockout mice is a deficiency in blood vessel development, initially observed in the gastrointestinal system (Tachibana et al. 1998). Consistent with such observations, CXCR4 receptors have been shown to be expressed by hemangioblasts, the earliest common precursor to hematopoietic and endothelial stem cells, found in yolk sac... 

Sato et al. (1991) expanded their earlier PBPK model to account for differences in body weight, body fat content, and sex and applied it to predicting the effect of these factors on trichloroethylene metabolism and excretion. Their model consisted of seven compartments (lung, vessel rich tissue, vessel poor tissue, muscle, fat tissue, gastrointestinal system, and hepatic system) and made various assumptions about the metabolic pathways considered. First-order Michaelis-Menten kinetics were assumed for simplicity, and the first metabolic product was assumed to be chloral hydrate, which was then converted to TCA and trichloroethanol. Further assumptions were that metabolism was limited to the hepatic compartment and that tissue and organ volumes were related to body weight. The metabolic parameters, (the scaling constant for the maximum rate of metabolism) and (the Michaelis constant), were those determined for trichloroethylene in a study by Koizumi (1989) and are presented in Table 2-3. 

ROBERFROID M B (1996) Functional effects of food components and the gastrointestinal system chicory fructooligosaccharides. Nutr Rev. 54 S38-42. 

Casein refers to a family of proteins, namely, ttgi-, 0. 2-, p-, and k-caseins (Table 5.1). Digestion of a- and p-caseins leads to production of peptides that may bind to opioid receptors that exist in the nervous, endocrine, immime, or gastrointestinal system (Kampa et ah, 1996 Meisel, 2004). These compoimds may modulate absorption processes in the gut and can potentially affect gastrointestinal fimction through transit... 

Explain why barium sulfate is used in X-ray 2. Explain why using a base such as baking soda diagnosis of the gastrointestinal system. is effective in cleaning up a spill of an acid,... 

Nausea and vomiting are due to complex interactions of the gastrointestinal system, the vestibular system, and various portions of the brain. Nausea and vomiting have a variety of causes that can be simple or complex. Preventing and treating... 

Zweibaum A, M Laburthe, E Grasset, D Louvard. (1991). Use of cultured cell lines in studies of intestinal cell differentiation and function. In M Field, CA Frizzell, eds. Handbook of Physiology, Section 6, The Gastrointestinal System, Vol. IV, Intestinal Absorption and Secretion. Bethesda, MD Am Physiol Society, pp 223-255. 

Table 4.2 shows the number of groups within which pharmaceutical presentations are classified at different levels of therapeutic differentiation. The classifications are made up of 15 and 14 main therapeutic chapters in England and Spain respectively. At this level, products are grouped according to their therapeutic effect in terms of the main anatomical systems gastrointestinal system, cardiovascular system, respiratory system and so on. 

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