Acronym for High Altitude pulmonary edema, the accumulation in the lungs of extravascular fluid (fluid outside of blood vessels) at high altitude, a consequence of rapid altitude ascent, especially when that ascent is accompanied by significant exercise.
HAPE leads to dyspnea (shortness of breath), cough, tachycardia (fast heart rate) and decreased arterial oxygen levels. HAPE varies in degree from very mild to potentially fatal.
Some people may be genetically susceptible to HAPE. People who develop HAPE have smaller lungs, higher pulmonary artery pressures, and higher pulmonary artery wedge pressures during exercise at sea level than those who do not develop HAPE.
The incidence of HAPE has been analyzed in a prospective study of people climbing a 4500-meter mountain. 15% of climbers had clearcut evidence of HAPE from examination of the chest (by stethoscope or X-ray) after their climb. There is probably a risk of HAPE for most climbers if the rate of ascent and degree of physical effort are great enough. (Lancet Jan. 24, 2002).
The planning and pacing of ascents is of critical importance. HAPE tends to be less frequent on well-planned ascents to much greater heights, despite the greater degree of hypoxemia (low blood oxygen levels).
A set of chromosomes that contains only one member of each chromosome pair. The sperm and egg are haploid and, in humans, each has 23 chromosomes.
In immunology, a molecule that is incapable, alone, of causing the production of antibodies but which can do so when fastened to a larger antigenic molecule called a carrier. The term “hapten” was taken from the Greek verb “haptein” meaning “to fasten or bind.” Haptin and haptene are alternative forms of this term that was […]
A situation in which the total level of a gene product (a particular protein) produced by the cell is about half of the normal level and that is not sufficient to permit the cell to function normally. Another way to define haploinsufficiency is as a condition that arises when the normal phenotype requires the protein […]
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An acute highly contagious viral disease with fever, runny nose, cough, red eyes, and a spreading skin rash. The eight-day measles is the ordinary measles, also known as rubeola, a potentially disastrous disease. Measles may be complicated by ear infections, pneumonia, encephalitis (that can cause convulsions, mental retardation. and even death), the sudden onset of […]
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The first section of the bony part of the roof of the mouth, located in front of the soft palate.