oncosphere


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oncosphere

 [ong´ko-sfēr]
the larva of the tapeworm contained within the external embryonic envelope and armed with six hooks.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

hex·a·canth

(hek'să-kanth),
The motile six-hooked first-stage larva of cyclophyllidean cestodes; it emerges from the egg and actively claws its way through the intermediate host's intestine before development into the next larval stage; for example, the hexacanth of Taenia saginata, which penetrates the intestine of a cow that ingested the egg, then forms a cysticercus in the muscles of the intermediate host.
Synonym(s): oncosphere
[hexa- + G. akantha, hook or thorn]
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Depending on water temperature, an embryo (six-hooked oncosphere or hexacanth) is formed within the egg in a few days.
After ingestion of the eggs by the intermediate hosts, the larva (oncosphere) hatches from the egg, penetrates the intestinal mucosa, reaches the bloodstream, and migrates to the liver, lungs, and other internal organs.
From stillness to motion: 80 years after the first description of Taenia solium oncosphere hatching.
Once ingested, the oncosphere hatches and penetrates the small intestine to migrate to various organs and tissues, where it develops into one or more hydatid cysts (6).
After ingestion of the egg, the embryo (oncosphere) hatches, penetrates the intestinal mucosa, enters into the host's circulatory system (via venous and lymphatic pathways), and develops into the characteristic vesicular metacestode when reaching a suitable anatomical site, assuming the intermediate host's immune system is unable to destroy the oncosphere [1].
Infection of the intermediate host occurs by incidental ingestion of the oncosphere that develops in the liver and lungs to hydatid fluid filled cyst with protoscolices and daughter cysts (2).
(d) Oncosphere forming assay (number of colonies, left panel) and bromodeoxyuridine (BrdU) uptake (right panel) in NSCs after ectopic expression of HA-[beta]arr-1.
Each egg contained an oncosphere that hatched and activated in small intestine.
A double etiopathogenic mechanism is possible, with the primitive blood-graft of oncosphere or hexcanth and a graft in the pelvic pouch of Douglas of protoscolices coming from the cracking of abdominal hydatid cysts.
Hydatid disease is a zoonosis caused by the infestation of the oncosphere (embryo) of Echinococcus Granulosus.