Monday, February 28, 2011

Anabolic Steroids


A family of steroids related to the male sex hormone TESTOSTERONE. These are classified as prescription drugs used to make up for hormone imbalance and deficiencies. However, synthetic analogs of testosterone have been obtained illegally by athletes and by teenage males to build muscles, and the U.S. FDA has described steroid abuse as a drug epidemic. While testosterone stimulates growth during adolescence, the synthetic derivatives can cause many side effects. Athletes compound this unsafe practice by “stacking” anabolic steroids—taking a combination of brands at 10 to 100 times the recommended doses for weeks at a time.
In men, the side effects of anabolic steroid use include lowered sperm count, enlarged prostate gland, shrinking testicles, balding, and enlarged breasts. If taken before puberty, anabolic steroids can stunt growth. These effects seem to be reversible if anabolic steroids have been used for a short time. Some women body builders also use steroids to build muscle. Side effects in women do not seem to be reversible: masculinization, including increased muscles, increased size of clitoris, growth of facial hair, a deepening voice, shrinkage of breast size, uterine atrophy, and menstrual irregularities. Severe cases of acne and bouts of rage are signs of anabolic steroid use, especially in males. Anabolic steroid use can have more subtle, longterm detrimental effects; damage may show up years later as a HEART ATTACK, high blood pressure, CANCER, and LIVER damage in both men and women.

Amylose

A water-soluble form of STARCH found in seeds, tubers, and root vegetables. It is made up of long chains of GLUCOSE units, and often contains a thousand or more glucose units. Amylose differs from the other prevalent form of starch, AMYLOPECTIN, which is highly branched. Amylose forms large spiral configurations when dissolved in water and can react with iodide to form a characteristic blue-purple pigment. Amylopectin and amylose occur together in starch, and the relative amounts vary depending on the plant sources. During digestion, AMYLASE breaks down amylose to maltose, a disaccharide composed of two glucose units. An intestinal enzyme, MALTASE, then hydrolyzes maltose to the simple sugar glucose, the ultimate product of starch digestion.

Amylopectin

The water-insoluble form of STARCH. Plants synthesize this very long chain of GLUCOSE units as a storage form of energy, often to nurture the future embryo, seedling or sprout. It is often the major form of starch and it possesses a highly branched, bushy structure resembling liver GLYCOGEN (animal starch). In contrast, AMYLOSE is made up of single straight chains of glucose units.
Amylopectin forms a paste in hot water. Starch occurs in seeds, tubers, and root vegetables as both amylopectin and amylose, although the ratio of two forms varies with the source. Cooking softens starch granules, making them available to DIGESTION by AMYLASE. The ultimate product of amylopectin digestion is GLUCOSE. Commercial processing converts starch to glucose, then to HIGHFRUCTOSE CORN SYRUP, a major sweetener