An uncommon noncancerous tumour that develops from placental tissue early in a pregnancy in which the embryo has failed to develop normally. The mole, which resembles a bunch of grapes, is caused by degeneration of the chorionic villi. The cause of the degeneration is unknown. In a small number of affected pregnancies, the mole develops into a choriocarcinoma.Vaginal bleeding and severe morning sickness generally occur. Ultrasound scanning reveals the tumour. Urine and blood tests detect excessive amounts of human chorionic gonadotrophin (see gonadotrophin, human chorionic), which
is produced by the tumour.
The tumour can be removed by suction, a D and C, or, less commonly, a hysterectomy.
A rare complication of pregnancy, in which there is tremendous proliferation of the epithelium of the chorion (the outer of the two fetal membranes). It seldom occurs during a ?rst pregnancy. Treatment consists of immediate evacuation of the womb.
a collection of fluid-filled sacs that develop when the membrane (chorion) surrounding the embryo degenerates in early pregnancy with proliferation of the *trophoblast. These sacs give the placenta the appearance of a bunch of grapes and a characteristic snowstorm appearance on ultrasound. The levels of hCG are abnormally high. Hydatidiform mole can be subdivided into complete and partial mole based on genetic and histological features. Complete moles show no evidence of fetal tissue; there is usually evidence of a fetus or fetal red blood cells with a partial mole. The widespread use of ultrasound has led to earlier diagnosis and has changed the pattern of molar pregnancy. The majority of women present with symptoms of early pregnancy failure. See gestational trophoblastic disease.
The smallest possible amount of a substance comprising two or more linked atoms which retains the chemical characteristics of that substance. Molecules vary greatly in their size and complexity, ranging from oxygen (two linked oxygen atoms) and water (two hydrogen atoms and one oxygen) to large complex molecules such as deoxyribonucleic acid (DNA) comprising thousands of atoms of carbon, hydrogen, oxygen, nitrogen and phosphorus that form the double-helix structure which helps to form GENES, the basic building blocks of the hereditary material of living things.... molecule
molecules on the surface of cell membranes that are responsible for most cellular functions directly related to their immediate environment. Many have very precise functions of adhesion (see adhesion molecules), metabolic exchange, hormone reception, respiration, and immune reactions. Cell-to-cell exchanges involve specialized surface structures (junctions), which form a communicating nexus.... cell-surface molecules
a type of *heparin that is more readily absorbed and requires less frequent administration than standard heparin preparations used as *parenteral anticoagulant therapy to prevent and treat deep vein thrombosis following surgery or during kidney dialysis. Preparations in use include, dalteparin sodium, enoxaparin sodium, and tinzaparin sodium.... low-molecular-weight heparin
an emerging area of imaging that exploits recent developments of molecular and cell biology to create new markers. Most molecular imaging uses versions of these markers labelled with radioactive isotopes, which – after administration – are localized in the body and can be detected using such techniques as *positron emission tomography, *SPECT scanning, *magnetic resonance imaging, and optical imaging.... molecular imaging
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