Prostate-specific antigen

Prostate-specific antigen (PSA), also known as gamma-seminoprotein or kallikrein-3 (KLK3), is a glycoprotein enzyme encoded in humans by the KLK3 gene. PSA is a member of the kallikrein-related peptidase family and is secreted by the epithelial cells of the prostate gland. PSA is produced for the ejaculate, where it liquefies semen in the seminal coagulum and allows sperm to swim freely. It is also believed to be instrumental in dissolving cervical mucus, allowing the entry of sperm into the uterus.

PSA is present in small quantities in the serum of men with healthy prostates, but is often elevated in the presence of prostate cancer or other prostate disorders. The United States Preventive Services Task Force (USPSTF, 2012) does not recommend PSA screening for prostate cancer, noting that the test may result in “overdiagnosis” and “overtreatment” because "most prostate cancer is asymptomatic for life" and treatments involve risks of complications including impotence (erectile dysfunction) and incontinence. The USPSTF concludes "the potential benefit does not outweigh the expected harms." PSA is not a unique indicator of prostate cancer, but may also detect prostatitis or benign prostatic hyperplasia. 30 percent of patients with high PSA have prostate cancer diagnosed after biopsy.

PSA

PSA, PsA, Psa, or psa may refer to:

Airlines and airports

Art

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Computing

Contracts, legislation, and government

Prostate cancer

Prostate cancer, also known as carcinoma of the prostate, is the development of cancer in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, some grow relatively quickly. The cancer cells may spread from the prostate to other parts of the body, particularly the bones and lymph nodes. It may initially cause no symptoms. In later stages it can lead to difficulty urinating, blood in the urine, or pain in the pelvis, back or when urinating. A disease known as benign prostatic hyperplasia may produce similar symptoms. Other late symptoms may include feeling tired due to low levels of red blood cells.

Factors that increase the risk of prostate cancer include: older age, a family history of the disease, and race. About 99% of cases occur in those over the age of 50. Having a first degree relative with the disease increases the risk 2 to 3 fold. In the United States it is more common in the African American population than the White American population. Other factors that may be involved include a diet high in processed meat, red meat, or milk products or low in certain vegetables. An association with gonorrhea has been found, but a reason for this relationship has not been identified. Prostate cancer is diagnosed by biopsy. Medical imaging may then be done to determine if the cancer has spread to other parts of the body.

John M. Ford

John Milo "Mike" Ford (April 10, 1957 – September 25, 2006) was an American science fiction and fantasy writer, game designer, and poet.

Ford was regarded (and obituaries, tributes and memories describe him) as an extraordinarily intelligent, erudite and witty man. He was a popular contributor to several online discussions. He composed poems, often improvised, in both complicated forms and blank verse, notably Shakespearean pastiche; he also wrote pastiches and parodies of many other authors and styles. At Minicon and other science fiction conventions he would perform "Ask Dr. Mike", giving humorous answers to scientific and other questions in a lab coat before a whiteboard.

Life

Ford was born in East Chicago, Indiana, and raised in Whiting, Indiana. In the mid-1970s he attended Indiana University Bloomington, where he was active in the IU science fiction club and Society for Creative Anachronism (using the name Miles Atherton de Grey); while there, he published his first short story "This, Too, We Reconcile" in the May 1976 Analog.

Prostate

The prostate (from Greek προστάτης, prostates, literally "one who stands before", "protector", "guardian") is a compound tubuloalveolar exocrine gland of the male reproductive system in most mammals. It differs considerably among species anatomically, chemically, and physiologically.

The function of the prostate is to secrete a slightly alkaline fluid, milky or white in appearance, that in humans usually constitutes roughly 30% of the volume of the semen along with spermatozoa and seminal vesicle fluid. Semen is made alkaline overall with the secretions from the other contributing glands, including, at least, the seminal vesicle fluid. The alkalinity of semen helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm. The prostatic fluid is expelled in the first ejaculate fractions, together with most of the spermatozoa. In comparison with the few spermatozoa expelled together with mainly seminal vesicular fluid, those expelled in prostatic fluid have better motility, longer survival and better protection of the genetic material.