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February 10, 2012

Low Testosterone (Low T) Glossary of Terms

The following are health and medical definitions of terms that appear in the Low Testosterone (Low T) article.

Abdomen: The belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs.
See the entire definition of Abdomen

Abnormal: Not normal. Deviating from the usual structure, position, condition, or behavior. In referring to a growth, abnormal may mean that it is cancerous or premalignant (likely to become cancer).

Aging: The process of becoming older, a process that is genetically determined and environmentally modulated.
See the entire definition of Aging

Ambiguous genitalia: Genitalia that are neither typically female nor typically male. Also known as intersexual genitalia.
See the entire definition of Ambiguous genitalia

Androgenic: Pertaining to the development of male characteristics, including body hair, the genital organs and muscle mass. "Androgenic" is the adjective form of the noun "androgen," a word referring to any of the male hormones, including testosterone and androsterone.
See the entire definition of Androgenic

Bilateral: Having, or relating to, two sides. Bilateral is as opposed, for example, to unilateral (which means having, or relating to, one side).

Bone density: Bone density is the amount of bone tissue in a certain volume of bone. It can be measured using a special x-ray called a quantitative computed tomogram.

Brain: That part of the central nervous system that is located within the cranium (skull). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres."

Brain stem: The stemlike part of the brain that is connected to the spinal cord. Or conversely, the extension of the spinal cord up into the brain. The brain stem is small but important. It manages messages going between the brain and the rest of the body, and it also controls basic body functions such as breathing, swallowing, heart rate, and blood pressure. The brain stem also controls consciousness and determines whether one is awake or sleepy.
See the entire definition of Brain stem

Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread).
See the entire definition of Cancer

Cheek: The side of the face forming the side wall of the mouth.
See the entire definition of Cheek

Chemotherapy: 1. In the original sense, a chemical that binds to and specifically kills microbes or tumor cells. The term chemotherapy was coined in this regard by Paul Ehrlich (1854-1915).
2. In oncology, drug therapy for cancer. Also called "chemo" for short.
See the entire definition of Chemotherapy

Chromosome: A visible carrier of the genetic information.
See the entire definition of Chromosome

Chromosomes: The microscopically visible carriers of the genetic material. They are composed of deoxyribonucleic acid (DNA) and proteins and, under a microscope, look like little rods.
See the entire definition of Chromosomes

Complication: In medicine, an additional problem that arises following a procedure, treatment or illness and is secondary to it. A complication complicates the situation.

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Diagnosis: 1 The nature of a disease; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies. 3 The identification of any problem. The diagnosis was a plugged IV.
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Dysfunction: Difficult function or abnormal function.
See the entire definition of Dysfunction

Erectile dysfunction: A common men's health problem characterized by the consistent inability to sustain an erection sufficient for sexual intercourse or the inability to achieve ejaculation, or both. Impotence can vary. It can involve a total inability to achieve an erection or ejaculation, an inconsistent ability to do so, or a tendency to sustain only very brief erections. Erectile dysfunction is also called impotence,
See the entire definition of Erectile dysfunction

Estrogen: Estrogen is a female hormone produced by the ovaries. Estrogen deficiency can lead to osteoporosis.
See the entire definition of Estrogen

Estrogens: Female hormones produced by the ovaries. Estrogen deficiency can lead to osteoporosis.
See the entire definition of Estrogens

FDA: The Food and Drug Administration, an agency within the U.S. Public Health Service, which is a part of the Department of Health and Human Services.
See the entire definition of FDA

Female genitalia: The genital organs of the female. These are usually separated by convention into the external and internal genitalia.
See the entire definition of Female genitalia

Fetus: The unborn offspring from the end of the 8th week after conception (when the major structures have formed) until birth. Up until the eighth week, the developing offspring is called an embryo.

Genital: Pertaining to the external and internal organs of reproduction. (Not to be confused with genetic.)

Genitalia: The male and female reproductive organs. The genitalia include internal structures such as the ovary, and external structures such as the penis. See also: Female organs of reproduction; Male organs of reproduction.

Gland: 1. A group of cells that secrete a substance for use in the body. For example, the thyroid gland. 2. A group of cells that removes materials from the circulation. For example, a lymph gland.

Gynecomastia: Excessive development of the male breasts. Temporary enlargement of the breasts is not unusual or abnormal in boys during adolescence or during recovery from malnutrition. Gynecomastia may be abnormal as, for example, in Klinefelter's syndrome.
See the entire definition of Gynecomastia

HIV: Acronym for the Human Immunodeficiency Virus, the cause of AIDS (acquired immunodeficiency syndrome). HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus. No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase, the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism).
See the entire definition of HIV

Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs.
See the entire definition of Hormone

Hypogonadism: A condition in which decreased production of gonadal hormones leads to below-normal function of the gonads and to retardation of sexual growth and development. (The gonads are the ovaries and testes and the hormones they normally produce include estrogen, progesterone, and testosterone.)

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Hypothalamus: The area of the brain that controls body temperature, hunger, and thirst.

Immunization: Vaccination. Immunizations work by stimulating the immune system, the natural disease-fighting system of the body. The healthy immune system is able to recognize invading bacteria and viruses and produce substances (antibodies) to destroy or disable them. Immunizations prepare the immune system to ward off a disease. To immunize against viral diseases, the virus used in the vaccine has been weakened or killed. To immunize against bacterial diseases, it is generally possible to use only a small portion of the dead bacteria to stimulate the formation of antibodies against the whole bacteria. In addition to the initial immunization process, it has been found that the effectiveness of immunizations can be improved by periodic repeat injections or "boosters." Also see Immunizations (in the plural) and Immunization of a specific type (such Immunization, Polio).

Incidence: The frequency with which something, such as a disease, appears in a particular population or area. In disease epidemiology, the incidence is the number of newly diagnosed cases during a specific time period. The incidence is distinct from the prevalence which refers to the number of cases alive on a certain date.

Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person.
See the entire definition of Infection

Infertility: The diminished ability or the inability to conceive and have offspring. Infertility is also defined in specific terms as the failure to conceive after a year of regular intercourse without contraception.
See the entire definition of Infertility

Inflammation: A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain. Inflammation is now recognized as a type of nonspecific immune response.
See the entire definition of Inflammation

Injury: Harm or hurt. The term "injury" may be applied in medicine to damage inflicted upon oneself as in a hamstring injury or by an external agent on as in a cold injury. The injury may be accidental or deliberate, as with a needlestick injury. The term "injury" may be synonymous (depending on the context) with a wound or with trauma.

Interstitial: Pertaining to being between things, especially between things that are normally closely spaced.
See the entire definition of Interstitial

Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."

Libido: 1. Sexual drive. 2. In psychoanalysis, the psychic energy from all instinctive biological drives.
See the entire definition of Libido

Low testosterone: Abnormally low levels of the male sex hormone testosterone in the blood. Testosterone is produced by the testes and to a lesser extent by the adrenal glands. Testosterone encourages the development of male sexual characteristics at puberty, stimulates the activity of the male secondary sex characteristics, drives the production of sperm, and is involved in regulation of muscle mass and sex drive. Testosterone levels are highly regulated by a complex glandular system. Abnormally low testosterone levels can occur due to a number of conditions affecting the glands that regulate and produce this hormone. Symptoms of low testosterone include decreased libido, impotence or erectile dysfunction, breast enlargement, and a lowered sperm count. Low testosterone levels may be treated with hormone therapy.

Menopause: The time in a woman's life when menstrual periods permanently stop; it is also called the "change of life." Menopause is the opposite of the menarche.
See the entire definition of Menopause

Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.

Mumps: An acute (sudden, shortlived) viral illness that usually presents with inflammation of the salivary glands, particularly the parotid glands. A child with mumps often looks like a chipmunk with a full mouth due to the swelling of the parotids (the salivary glands near the ears).
See the entire definition of Mumps

Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."

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Obesity: The state of being well above one's normal weight.
See the entire definition of Obesity

Oophorectomy: The removal of one or both ovaries by surgery. Also known as ovariectomy.

Orchitis: Inflammation of the testis (male sex organ). There are many causes of inflammation of the testis including infections (such as mumps), diseases (such as polyarteritis nodosa), or injury. Also called orchiditis.

Organ: A relatively independent part of the body that carries out one or more special functions. The organs of the human body include the eye, ear, heart, lungs, and liver.

Osteoporosis: Thinning of the bones with reduction in bone mass due to depletion of calcium and bone protein. Osteoporosis predisposes a person to fractures, which are often slow to heal and heal poorly. It is more common in older adults, particularly post-menopausal women; in patients on steroids; and in those who take steroidal drugs. Unchecked osteoporosis can lead to changes in posture, physical abnormality (particularly the form of hunched back known colloquially as "dowager's hump"), and decreased mobility.
See the entire definition of Osteoporosis

Ovarian: Of or pertaining to the ovary.

Ovary: The female gonad, the ovary is one of a pair of reproductive glands in women. They are located in the pelvis, one on each side of the uterus. Each ovary is about the size and shape of an almond. The ovaries produce eggs (ova) and female hormones. During each monthly menstrual cycle, an egg is released from one ovary. The egg travels from the ovary through a fallopian tube to the uterus. The ovaries are the main source of female hormones, which control the development of female body characteristics, such as the breasts, body shape, and body hair. They also regulate the menstrual cycle and pregnancy.

Pediatric: Pertaining to children.

Penis: The external male sex organ used to copulate and ejaculate semen and to convey urine outside the body.
See the entire definition of Penis

Pituitary: 1. As an adjective, pertaining to the pituitary gland or its hormonal secretions. 2. As a noun, the pituitary gland itself.
See the entire definition of Pituitary

Pituitary gland: The main endocrine gland. It is a small structure in the head. It is called the master gland because it produces hormones that control other glands and many body functions including growth. The pituitary consists of the anterior and posterior pituitary.
See the entire definition of Pituitary gland

Prognosis: 1. The expected course of a disease.
2. The patient's chance of recovery.
The prognosis predicts the outcome of a disease and therefore the future for the patient. His prognosis is grim, for example, while hers is good.
See the entire definition of Prognosis

Protein: A large molecule composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein.
See the entire definition of Protein

Puberty: A complex biologic and psychologic process involving sexual development, accelerated growth, and adrenal maturation heralded by the secretion of gonadotropin releasing hormone (GnRH) from a part of the brain called the hypothalamus. This event is the first known step in the reproductive cascade. It initiates the pulsatile release of gonadotropins, gonadal secretion of sex steroids, pubertal development, and gametogenesis (the production of sperm and ova).
See the entire definition of Puberty

Radiation: 1. Rays of energy. Gamma rays and X-rays are two of the types of energy waves often used in medicine. 2. The use of energy waves to diagnose or treat disease. See also: Irradiation.

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Radiation therapy: The use of high-energy rays to damage cancer cells, stopping them from growing and dividing. Like surgery, radiation therapy is a local treatment that affects cancer cells only in the treated area.
See the entire definition of Radiation therapy

Receptor: 1. In cell biology, a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance. There are many receptors. There is a receptor for (insulin; there is a receptor for low-density lipoproteins (LDL); etc. To take an example, the receptor for substance P, a molecule that acts as a messenger for the sensation of pain, is a unique harbor on the cell surface where substance P docks. Without this receptor, substance P cannot dock and cannot deliver its message of pain. Variant forms of nuclear hormone receptors mediate processes such as cholesterol metabolism and fatty acid production. Some hormone receptors are implicated in diseases such as diabetes and certain types of cancer. A receptor called PXR appears to jump-start the body's response to unfamiliar chemicals and may be involved in drug-drug interactions.
2. In neurology, a terminal of a sensory nerve that receives and responds to stimuli.

Sarcoidosis: A disease of unknown origin that causes small lumps (granulomas) due to chronic inflammation to develop in a great range of body tissues. Sarcoidosis can appear in almost any body organ, but most often starts in the lungs or lymph nodes. It also affects the eyes, liver and skin; and less often the spleen, bones, joints, skeletal muscles, heart and central nervous system (brain and spinal cord).
See the entire definition of Sarcoidosis

Scrotum: A pouch of skin which contains the testes, epididymides, and lower portions of the spermatic cords.

Sleep: The body's rest cycle.
See the entire definition of Sleep

Steroid: A general class of chemical substances that are structurally related to one another and share the same chemical skeleton (a tetracyclic cyclopenta[a]phenanthrene skeleton).
See the entire definition of Steroid

Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease.
See the entire definition of Syndrome

Systemic: Affecting the entire body. A systemic disease such as diabetes can affect the whole body. Systemic chemotherapy employs drugs that travel through the bloodstream and reach and affect cells all over the body.

Testes: The male sex glands. They are located behind the penis in a pouch of skin called the scrotum. The testes produce and store sperm, and are also the body's main source of male hormones, such as testosterone. These hormones control the development of the reproductive organs and other male characteristics, such as body and facial hair, low voice, and wide shoulders.
See the entire definition of Testes

Testicles: The testicles (also called testes or gonads) are the male sex glands. They are located behind the penis in a pouch of skin called the scrotum. The testicles produce and store sperm, and they are also the body's main source of male hormones (testosterone). These hormones control the development of the reproductive organs and other male characteristics, such as body and facial hair, low voice, and wide shoulders.

Testis: The testis (or testicle) is the male sex gland. A pair of testes are located behind the penis in a pouch of skin called the scrotum.
See the entire definition of Testis

Testosterone: A "male hormone" -- a sex hormone produced by the testes that encourages the development of male sexual characteristics, stimulates the activity of the male secondary sex characteristics, and prevents changes in them following castration. Chemically, testosterone is 17-beta-hydroxy-4-androstene-3-one.
See the entire definition of Testosterone

Testosterone replacement therapy: The practice of giving testosterone to treat conditions in which the testes do not produce enough testosterone. This may be due to absence, injury, or disease.
See the entire definition of Testosterone replacement therapy

Therapy: The treatment of disease.
See the entire definition of Therapy

TSH: Stands for thyroid stimulating hormone, a hormone produced by the pituitary gland at the base of the brain in response to signals from the hypothalamus gland in the brain. TSH promotes the growth of the thyroid gland in the neck and stimulates it to produce more thyroid hormones. When there is an excessive amount of thyroid hormones, the pituitary gland stops producing TSH, reducing thyroid hormone production. This mechanism maintains a relatively constant level of thyroid hormones circulating in the blood.
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Tuberculosis: A highly contagious infection caused by the bacterium called Mycobacterium tuberculosis. Abbreviated TB. Tubercles (tiny lumps) are a characteristic finding in TB. Diagnosis may be made by skin test, which if positive should will be followed by a chest X-ray to determine the status (active or dormant) of the infection. Tuberculosis is more common in people with immune system problems, such as AIDS, than in the general population. Treatment of active tuberculosis is mandatory by law in the US, and should be available at no cost to the patient through the public health system. It involves a course of antibiotics and vitamins that lasts about six months. It is important to finish the entire treatment, both to prevent reoccurrence and to prevent the development of antibiotic-resistant tuberculosis. Most patients with tuberculosis do not need to be quarantined, but it is sometimes necessary.
See the entire definition of Tuberculosis

Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult.
See the entire definition of Virus

Y chromosome: The sex chromosome found together with an X chromosome in most normal males. Once thought to be a genetic wasteland, the Y now is known to contain at least 20 genes, some of them unique to the Y including the male-determining gene and male fitness genes that are active only in the testis and are thought responsible for the formation of sperm. Other genes on the Y have counterparts on the X chromosome, are active in many body tissues and play crucial "housekeeping" roles with the cell.
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    • Tuberculosis
      • Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis bacteria. Symptoms include weakness, fever, weight loss, night sweats and in worse cases, chest pain, shortness of breath, and coughing up blood. A person with an active infection (a positive TB skin test, abnormal chest x-ray and TB bacteria in their sputum) requires treatment with izoniazid, rifampin, ethambutol and pyrazinaide.
    • Sarcoidosis
      • Sarcoidosis, a disease resulting from chronic inflammation, causes small lumps (granulomas) to develop in a great range of body tissues and can appear in almost any body organ. However, sarcoidosis most often starts in the lungs or lymph nodes.
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    • Infertility
      • Infertility is the diminished ability to conceive a child. The primary cause of infertility in men is a sperm disorder. In women, the primary cause of infertility is an ovulation disorder. Most forms of infertility can be treated. Conventional infertility therapies include drugs or surgery.
    • Obesity
      • Obesity is the state of being well above one's normal weight. A person has traditionally been considered to be obese if they are more than 20 percent over their ideal weight. That ideal weight must take into account the person's height, age, sex, and build.
    • Mumps
      • Mumps is an acute viral illness caused by the mumps virus. Symptoms of mumps include fever, headache, muscle aches, tiredness, and loss of appetite; followed by swelling of the salivary glands.
    • Gynecomastia
      • Gynecomastia, an enlargement of the gland tissue in the male breast is the caused by an imbalance of hormones. Certain medical conditions may also lead to gynecomastia such as cirrhosis, malnutrition, disorders of the male sex organs, kidney failure, thyroid disorders, and medications. Gynecomastia is generally treated with medication, and if necessary surgery.
    • Klinefelter Syndrome
      • Klinefelter syndrome, also referred to as XXY condition, is a genetic disease. Klinefelter syndrome affects mostly males. Symptoms include decreased testosterone levels, development of breasts, wider hips, and infertility. Some men with Klinefelter syndrome have no symptoms. Treatment includes educational, therapeutic, and medical therapy.
    • Prolactinoma (Pituitary Tumor)
      • Prolactinoma is an adenoma (benign tumor) of the pituitary gland. Causes of many prolactinomas are unknown. Symptoms in women include changes in menstruation and infertility, decreased libido, or painful intercourse due to vaginal dryness. The most common symptom in men is impotence (erectile dysfunction). Treatment of prolactinomas are medication or surgery.
    • Steroid Abuse
      • Anabolic steroids are synthetic substances that are related to testosterone and promote skeletal muscle growth and the development of male sexual characteristics in both men and women. In the 1930s, it was discovered that anabolic steroids could promote skeletal muscle growth in lab animals, which lead to anabolic steroid abuse by bodybuilders and weight lifters.
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      • Premature ovarian failure (POS) is the cessation of normal functioning of the ovaries in women under the age of 40. Premature ovarian failure may be caused by follicle depletion or dysfunction. The most common symptom of premature ovarian failure are irregular periods. There is no "treatment" that will restore the ovarian function, but there are treatments that my relieve symptoms.
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      • Men's health is an important component to a happy lifestyle and healthy relationships. Eating healthy, exercise, managing stress, and knowing when to have medical tests for a particular age is key to disease prevention in men.
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Low Testosterone (Low T)

What is erectile dysfunction?

Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain an erection for satisfactory sexual activity. Erectile dysfunction is different from other conditions that interfere with male sexual intercourse, such as lack of sexual desire (decreased libido) and problems with ejaculation and orgasm (ejaculatory dysfunction). This article focuses on the evaluation and treatment of erectile dysfunction.

How common is erectile dysfunction?

Erectile dysfunction (ED, impotence) varies in severity; some men have a total inability to achieve an erection, others have an inconsistent ability to achieve an erection, and still others can sustain only brief erections. The variations in severity of erectile dysfunction make estimating its frequency difficult. Many men also are reluctant to discuss erectile dysfunction with their doctors due to embarrassment, and thus the condition is unde...

Read the Erectile Dysfunction (Impotence) article »




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