Friday, June 28, 2013

Prostate cancer

One of the most relevant pieces of evidence in favor of the causal association between sex steroids and prostate cancer has been provided by animal studies. Long-term administration of testosterone and estradiol to Noble rats results in a high incidence of adenocarcinomas in the dorsolateral prostate. The combined treatment of intact Noble rats with testosterone and estradiol, but not the separate administration of these gonadal steroids alone, induced florid dysplasia and markedly elevated mitotic index in the rat dorsolateral prostates. It has been suggested that protracted androgen-supported estrogen-enhanced stimulation of cell proliferation may be required to develop dysplastic lesions in the rat prostate. More recently, a 5-8-week treatment with testosterone and estradiol induced atypical hyperplasia and carcinoma in male nude mouse grafted with retinoblastoma-null mouse embryonic prostates, suggesting that deletion of the retinoblastoma gene predisposes prostatic epithelium to hyperplasia and enhances its susceptibility to hormonal carcinogenesis.

High levels of endogenous gonadal steroids are considered to be risk factors for prostate cancer. However, while the association of sex steroids with prostate cancer is supported by biological evidence, epidemiological studies have reported inconclusive data. Analytical studies using direct measurement of serum steroid levels in relation to prostate cancer risk have shown inconsistent results. Measurement of endogenous hormones in blood or urine poses many methodological and logistic problems, including variations in biological specimen collection and assay methods. These problems may explain, at least in part, the inconsistency of previous study results.

In specific tissues of the body, including prostate, the balance between androgens and estrogens may differ significantly from that in the plasma, being dependent upon the presence and activity of steroid-metabolizing enzymes, such as 5a-reductase and aromatase.

Thursday, June 20, 2013

Prostate cancer

Chemotherapy is the use of drugs to control cancer's growth or relieve pain. Often the drugs are given through a needle in your vein, and your blood vessels carry the drugs through your body. Sometimes the drugs are available as pills you can swallow. Sometimes they are given through a shot, or injection.

Chemotherapy usually involves two or more drugs given together. This is done to lower the chances that the cancer cells will become resistant to the drugs. It is most often used when prostate cancer is hormone-resistant.

Pain-relief and appetite-stimulant drugs:
Pain-relief and appetite stimulant drugs may be used when prostate cancer has spread to other parts of the body. Steroids, such as hydrocortisone or prednisone, control pain and improve appetite. Radioactive drugs such as strontium-89 and samarium-153 are called radionuclides. They are absorbed near the area of bone pain. Then the radiation that is released helps relieve the pain caused by tumors that have spread to the bone. Bisphosphonate drugs such as zoledronic acid (Zometa) and pamidronate disodium (Aredia) may help relieve bone pain and prevent osteoporosis, which is sometimes caused by long-term hormone therapy.

Friday, June 14, 2013

Viagra and Cialis popular among bodybuilders

For the past time men are buying Viagra every day and buying Viagra is much more than aspirin buying. In 1998 the Viagra was used to solve impotence in man. The active substance of the Viagra is Sildenafil which can be compared with Cialis. The basic difference of the Cialis and Viagra is the activity period of the two Sildenafil. The activity period of Viagra is only 4 to 6 hours while the activity period of the Cialis is about 36 hours.  Though the activity period is less but it is more active to keep a long erection. The main reason to buy Viagra is its cheap price and readily available on the market and online.

Viagra and Cialis are impotence drugs and are known to be popular among body builders to revive sexual drive after steroid cycles. Use of steroids can inhibit the natural production of androgens, leading to depressed hormonal levels after intake of these anabolic compounds. Men may experience erection problems because of this. Viagra is also used as pre-contest drug in body-building circles.