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Pharmacy is the health profession that links the health sciences with the chemical sciences and it is charged with ensuring the safe and effective use of pharmaceutical drugs. The word derives from the Greek: (pharmakon), meaning "drug" or "medicine". The scope of pharmacy practice includes more traditional roles such as compounding and dispensing medications, and it also includes more modern services related to health care, including clinical services, reviewing medications for safety and efficacy, and providing drug information. Pharmacists, therefore, are the experts on drug therapy and are the primary health professionals who optimize medication use to provide patients with positive health outcomes. An establishment in which pharmacy (in the first sense) is practiced is called a pharmacy, chemist's or drug store. In the United States and Canada, drug stores commonly sell not only medicines, but also miscellaneous items such as candy (sweets), cosmetics, and magazines, as well as light refreshments or groceries.

Thursday, May 3, 2012

Digestion, Absorption, and Transport of Carbohydrates

  • The major carbohydrates in the American diet are starch, lactose, and sucrose.
  • Starch is a polysaccharide composed of many glucose units linked together through α-1,4- and α-1,6-glycosidic bonds (see Fig.)
    N- and O-glycosidic bonds. ATP contains a β, N-glycosidic bond. Lactose contains an O-glycosidic β(1→4) bond. Starch contains α-1,4 and α-1,6 O-glycosidic bonds.
  • Lactose is a disaccharide composed of glucose and galactose.
  • Sucrose is a disaccharide composed of glucose and fructose.
  • Digestion converts all dietary carbohydrates to their respective monosaccharides.
  • Amylase digests starch; it is found in the saliva and pancreas, which releases it into the small intestine.
  • Intestinal epithelial cells contain disaccharidases, which cleave lactose, sucrose, and digestion products of starch into monosaccharides.
  • Dietary fiber is composed of polysaccharides that cannot be digested by human enzymes.
  • Monosaccharides are transported into the absorptive intestinal epithelial cells via active transport systems.
  • Monosaccharides released into the blood via the intestinal epithelial cells are recovered by tissues that utilize facilitative transporters.
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