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Lysosomal storage diseases (LSDs; /ˌlaɪsəˈsoʊməl/) are a group of approximately 50 rare inherited metabolic disorders that result from defects in lysosomal function. Lysosomes are sacs of enzymes within cells that digest large molecules and pass the fragments on to other parts of the cell for recycling.
Signs and symptoms of this condition typically appear around the age of 3 or 4 months, when babies start to sleep through the night and do not eat as frequently as newborns. Affected infants may have low blood sugar (hypoglycemia), which can lead to seizures. They can also have a buildup of lactic acid in the body (lactic acidosis), high blood levels of a waste product called uric acid (hyperuricemia), and excess amounts of fats in the blood (hyperlipidemia). As they get older, children with GSDI have thin arms and legs and short stature. An enlarged liver may give the appearance of a protruding abdomen. The kidneys may also be enlarged. Affected individuals may also have diarrhea and deposits of cholesterol in the skin (xanthomas).
The vast majority of glucocorticoid activity in most mammals is from cortisol, also known as hydrocortisone. Corticosterone, the major glucocorticoid in rodents, is another glucocorticoid. Cortisol binds to the glucocorticoid receptor in the cytoplasm and the hormone-receptor complex is then translocated into the nucleus, where it binds to its DNA response element and modulates transcription from a battery of genes, leading to changes in the cell's phenotype. Only about 10% of circulating cortisol is free. The remaining majority circulates bound to plasma proteins, particularly corticosteroid-binding globulin (transcortin). This protein binding likely decreases the metabolic clearance rate of glucocorticoids and, because the bound steroid is not biologically active, tends to act as a buffer and blunt wild fluctuations in cortisol concentration.
A retroverted uterus (tilted uterus, tipped uterus) is a uterus that is tilted posteriorly. This is in contrast to the slightly "anteverted" uterus that most women have, which is tipped forward toward the bladder, with the anterior end slightly concave.
The "great arteries" in this anomaly refer to the aorta and the pulmonary artery, the two major arteries carrying blood away from the heart. In cases of transposition of the great arteries, these vessels arise from the wrong ventricle. They are "transposed" from their normal position so that the aorta arises from the right ventricle and the pulmonary artery from the left ventricle. Other heart defects may occur along with transposition of the great arteries. About 25 percent of children with transposition will also have a ventricular septal defect (VSD) . In nearly a third, the branching pattern of the coronary arteries as they leave the transposed aorta is unusual. Infants may also have narrowing below the pulmonary valve that blocks blood flow from the left ventricle to the lungs.
Sound waves enter the ear canal and make the ear drum vibrate. This action moves the tiny chain of bones (ossicles – malleus, incus, stapes) in the middle ear. The last bone in this chain 'knocks' on the membrane window of the cochlea and makes the fluid in the cochlea move.
Mother-to-child transmission of HIV is the spread of HIV from an HIV-infected woman to her child during pregnancy, childbirth (also called labor and delivery), or breastfeeding (through breast milk). Mother-to-child transmission of HIV is also called perinatal transmission of HIV.
Phencyclidine (PCP) was developed in the 1950s as an intravenous anesthetic but, due to the side effects of confusion and delirium, its development for human medical use was discontinued. In its pure form, it is a white crystalline powder that readily dissolves in water or alcohol and has a distinctive bitter chemical taste. On the illicit drug market, Phencyclidine contains a number of contaminants as a result of makeshift manufacturing, causing the color to range from tan to brown, and the consistency to range from powder to a gummy mass. It is available in a variety of tablets, capsules, and colored powders, which are either taken orally or snorted. The liquid form of phencyclidine is actually phencyclidine base dissolved most often in ether, a highly flammable solvent. For smoking, phencyclidine is typically sprayed onto leafy material such as mint, parsley, oregano, or marijuana.
Frontotemporal dementia (frontotemporal lobar degeneration) is an umbrella term for a diverse group of uncommon disorders that primarily affect the frontal and temporal lobes of the brain — the areas generally associated with personality, behavior and language. In frontotemporal dementia, portions of these lobes shrink (atrophy). Signs and symptoms vary, depending upon the portion of the brain affected. Some people with frontotemporal dementia undergo dramatic changes in their personality and become socially inappropriate, impulsive or emotionally indifferent, while others lose the ability to use language.
Furosemide is a prescription drug. It’s available in two forms that you take by mouth: a tablet and a solution. It’s also available as an injectable solution, which is given by a healthcare provider. The furosemide tablet is available as the brand-name drug Lasix. It’s also available as a generic drug. Generic drugs usually cost less. In some cases, they may not be available in every strength or form as the brand-name version.
A leaking mitral valve allows blood to flow in two directions during the contraction. Some blood flows from the ventricle through the aortic valve – as it should – and some blood flows back into the atrium. A leaking (or regurgitant) aortic valve allows blood to flow in two directions. Oxygen-rich blood either flows out through the aorta to the body – as it should – or it flows backwards from the aorta into the left ventricle when the ventricle relaxes. Leaking valves can cause the heart to work harder to pump the same amount of blood.
In a normal person, when a muscle tendon is tapped briskly, the muscle immediately contracts due to a two-neuron reflex arc involving the spinal or brainstem segment that innervates the muscle. The afferent neuron whose cell body lies in a dorsal root ganglion innervates the muscle or Golgi tendon organ associated with the muscles; the efferent neuron is an alpha motoneuron in the anterior horn of the cord. The cerebral cortex and a number of brainstem nuclei exert influence over the sensory input of the muscle spindles by means of the gamma motoneurons that are located in the anterior horn; these neurons supply a set of muscle fibers that control the length of the muscle spindle itself.