Medical use
The pharmaceutical product and medical use of radium-223 against skeletal metastases was invented by Roy H. Larsen, Gjermund Henriksen and Øyvind S. Bruland and has been developed by the former Norwegian company Algeta ASA, in a partnership with Bayer, under the trade name Xofigo (formerly Alpharadin), and is distributed as a solution containing radium-223 chloride (1100 kBq/ml), sodium chloride, and other ingredients for intravenous injection. Algeta ASA was later acquired by Bayer who is now the sole owner of Xofigo. The recommended regimen is six treatments of 55 kBq/kg (1.5 μCi/kg), repeated at 4-week intervals. Mechanism of action
The use of radium-223 to treat metastatic bone cancer relies on the ability of alpha radiation from radium-223 and its short-lived decay products to kill cancer cells. Radium is preferentially absorbed by bone by virtue of its chemical similarity to calcium, with most radium-223 that is not taken up by the bone being cleared, primarily via the gut, and excreted. Although radium-223 and its decay products also emit beta and gamma radiation, over 95% of the decay energy is in the form of alpha radiation. Alpha radiation has a very short range in tissues compared to beta or gamma radiation: around 2-10 cells. This reduces damage to surrounding healthy tissues, producing an even more localized effect than the beta-emitter strontium-89, also used to treat bone cancer.
In anatomy, the precordium or praecordium is the portion of the body over the heart and lower chest.Defined anatomically, it is the area of the anterior chest wall over the heart. It is therefore usually on the left side, except in conditions like dextrocardia, where the individuals heart is on the right side. In such a case, the precordium is on the right side as well. The precordium is naturally a cardiac area of dullness. During examination of the chest, the percussion note will therefore be dull. In fact, this area only gives a resonant percussion note in hyperinflation, emphysema or tension pneumothorax. Precordial chest pain can be an indication of a variety of illnesses, including costochondritis and viral pericarditis. See also
Precordial thump
Precordial examination
Commotio cordis
Hyperdynamic precordium
Precordial catch syndrome


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