Kidney stone diseaseKidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine stream. A small stone may pass without causing symptoms. If a stone grows to more than , it can cause blockage of the ureter, resulting in sharp and severe pain in the lower back or abdomen. A stone may also result in blood in the urine, vomiting, or painful urination.
DihydrotestosteroneDihydrotestosterone (DHT, 5α-dihydrotestosterone, 5α-DHT, androstanolone or stanolone) is an endogenous androgen sex steroid and hormone. The enzyme 5α-reductase catalyzes the formation of DHT from testosterone in certain tissues including the prostate gland, seminal vesicles, epididymides, skin, hair follicles, liver, and brain. This enzyme mediates reduction of the C4-5 double bond of testosterone. DHT may also be synthesized from progesterone and 17α-hydroxyprogesterone via the androgen backdoor pathway in the absence of testosterone.
Neurogenic bladder dysfunctionNeurogenic bladder dysfunction, or neurogenic bladder, refers to urinary bladder problems due to disease or injury of the central nervous system or peripheral nerves involved in the control of urination. There are multiple types of neurogenic bladder depending on the underlying cause and the symptoms. Symptoms include overactive bladder, urinary urgency, frequency, incontinence or difficulty passing urine.
EjaculationEjaculation is the discharge of semen (the ejaculate; normally containing sperm) from the male reproductive tract as a result of an orgasm. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. Ejaculation can occur spontaneously during sleep, and is a normal part of human sexual development (a nocturnal emission or "wet dream"). In rare cases, ejaculation occurs because of prostatic disease. Anejaculation is the condition of being unable to ejaculate.
Prostate-specific antigenProstate-specific antigen (PSA), also known as gamma-seminoprotein or kallikrein-3 (KLK3), P-30 antigen, 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.
Frequent urinationFrequent urination, or urinary frequency (sometimes called pollakiuria), is the need to urinate more often than usual. Diuretics are medications that increase urinary frequency. Nocturia is the need of frequent urination at night. The most common cause of this condition for women and children is a urinary tract infection. The most common cause of urinary frequency in older men is an enlarged prostate. Frequent urination is strongly associated with frequent incidents of urinary urgency, which is the sudden need to urinate.
Prostate cancerProstate cancer is the uncontrolled growth of cells in the prostate, a gland in the male reproductive system just below the bladder. Early prostate cancer usually causes no symptoms. As the tumor grows, it can damage nearby organs causing erectile dysfunction, blood in the urine or semen, and trouble urinating. Some tumors eventually spread to other areas of the body, particularly the bones and lymph nodes. There, tumors cause severe bone pain, leg weakness or paralysis, and eventually death.
Medical ultrasoundMedical ultrasound includes diagnostic techniques (mainly imaging techniques) using ultrasound, as well as therapeutic applications of ultrasound. In diagnosis, it is used to create an image of internal body structures such as tendons, muscles, joints, blood vessels, and internal organs, to measure some characteristics (e.g. distances and velocities) or to generate an informative audible sound. The usage of ultrasound to produce visual images for medicine is called medical ultrasonography or simply sonography, or echography.
RectumThe rectum (: rectums or recta) is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult human rectum is about long, and begins at the rectosigmoid junction (the end of the sigmoid colon) at the level of the third sacral vertebra or the sacral promontory depending upon what definition is used. Its diameter is similar to that of the sigmoid colon at its commencement, but it is dilated near its termination, forming the rectal ampulla.
HypospermiaHypospermia is a condition in which a man has an unusually low ejaculate (or semen) volume, less than 1.5 mL. It is the opposite of hyperspermia, which is a semen volume of more than 5.5 mL. It should not be confused with oligospermia, which means low sperm count. Normal ejaculate when a man is not drained from prior sex and is suitably aroused is around 1.5–6 mL, although this varies greatly with mood, physical condition, and sexual activity. Of this, around 1% by volume is sperm cells. The U.S.
