Alzheimers disease, for example, is much more likely to develop in a person who has experienced a head injury. Brain damage, which is the destruction or degeneration of brain cells, is a common occurrence in those who experience a head injury. Neurotoxicity is another cause of brain damage that typically refers to selective, chemically induced neuron/brain damage. Classification
Head injuries include both injuries to the brain and those to other parts of the head, such as the scalp and skull. Head injuries can be closed or open. A closed (non-missile) head injury is where the dura mater remains intact. The skull can be fractured, but not necessarily. A penetrating head injury occurs when an object pierces the skull and breaches the dura mater. Brain injuries may be diffuse, occurring over a wide area, or focal, located in a small, specific area. A head injury may cause skull fracture, which may or may not be associated with injury to the brain. Some patients may have linear or depressed skull fractures. If intracranial hemorrhage occurs, a hematoma within the skull can put pressure on the brain. Types of intracranial hemorrhage include subdural, subarachnoid, extradural, and intraparenchymal hematoma. Craniotomy surgeries are used in these cases to lessen the pressure by draining off the blood.
Methoxy polyethylene glycol-epoetin beta is the active ingredient of a drug marketed by Hoffmann-La Roche under the brand name Mircera. Mircera is a long-acting erythropoietin receptor activator (CERA) indicated for the treatment of patients with anaemia associated with chronic kidney disease. It is the first approved, chemically modified erythropoiesis-stimulating agent (ESA). Mircera is supplied as a solution in pre-filled syringes for intravenous or subcutaneous administration. Mircera was approved for use in Europe in July 2007 by the European Commission, in September 2007 by the Swissmedic, and in November 2007 by the U.S. Food and Drug Administration for use in the United States. Methoxy polyethylene glycol-epoetin beta is made from erythropoietin by chemically linking the N-terminal amino group or the ε-amino group of any lysine present in the protein with methoxy polyethylene glycol butanoic acid. The average molecular weight is approximately 60 kDa. The drug stimulates erythropoiesis by interacting with the erythropoietin receptor on progenitor cells in the bone marrow. It has a reduced receptor binding activity compared to other ESAs and but retains in vivo activity due to an extended serum half-life. It has an in vivo half-life of around 135 hours (5.6 days) as compared to darbepoetin alfa which has a half life of around 21 to 70 hours, the half life of which is three times that of the naturally occurring erthropoietin in the body. It is on the World Health Organizations List of Essential Medicines.