It is chemically similar to the anti-cancer drug teniposide, being distinguished only by a methyl group where teniposide has a thienyl. Both these compounds have been developed with the aim of creating less toxic derivatives of podophyllotoxin.The substance is a white to yellow-brown, crystalline powder. It is soluble in organic solvents.It is used in form of its salt etoposide phosphate. History
Etoposide was first synthesized in 1966 and U.S. Food and Drug Administration approval was granted in 1983.The nickname VP-16 likely comes from a compounding of the last name of one of the chemists who performed early work on the drug (von Wartburg) and podophyllotoxin. Another scientist who was integral in the development of podophyllotoxin-based chemotherapeutics was the medical pharmacologist Hartmann F. Stähelin. References
External links
"Etoposide". Drug Information Portal. U.S. National Library of Medicine. "Etoposide phosphate". Drug Information Portal. U.S. National Library of Medicine. "Etoposide". National Cancer Institute. 12 August 2008. "Etoposide". NCI Drug Dictionary. National Cancer Institute.
Rachischisis can develop in conjunction with anencephaly, increasing the amount of area that is exposed. Although these conditions closely resemble one another, cases of rachischisis are morphologically different from cases of anencephaly, so they are indeed two separate conditions. Rachischisis is also a contributing factor to the onset of iniencephaly – a condition in which the spine is malformed. Further abnormalities such as rib malformations can occur with rachischisis. Stomach deformities can also develop with rachischisis. Risk factors
If a sibling of the fetus has been affected by rachischisis, there is increased risk that another child will develop the condition. There is also a slightly higher chance that females will develop the condition over males.Folate deficiency is also a well-accepted risk factor of all neural tube defects, including rachischisis. It is this reason that has caused many health policies regarding folic acid during pregnancy to be developed. Diagnosis
Initial diagnosis is typically by ultrasonography to reveal any congenital abnormalities. Fetuses affected typically show cranial abnormalities and deformities in brain tissue as well as spinal abnormalities. Following ultrasonography, magnetic resonance imaging (MRI) is commonly used to confirm the diagnosis. The presence of rachischisis is indicated in imaging by the absence of an arch-cranial line.Other neural tube defect diagnostic tools such as assays of α-fetoprotein or acetylcholinesterase may also be helpful in determining any other conditions that can lead to development of rachischisis. Classification
Rachischisis occurs most commonly in utero during the development of the child.