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1. A small spheric structure.
2. A sporangiallike structure filled with endospores at maturity, produced within tissue and in vitro by Coccidioides immitis.
[LL. sphaerula, dim. of L. sphaera, sphere, ball]


Etymology: Gk, sphaira, ball
a small ball.


A thick-walled, nonbudding structure recognized as the tissue form of Coccidioides immitis; variable in size, it may contain endospores or granular material. When the spherule ruptures, it releases endospores into the surrounding tissues.
[LL. sphaerula, dim. of L. sphaera, sphere, ball]


a thick-walled structure containing large numbers of fungal spores.
References in periodicals archive ?
Moreover, industrial spherules may contaminate the natural glasses, both at the outcrop and during laboratory treatments [3-5].
Examinations of the YDB spherules revealed that while they are consistent with the type of sediment found on the surface of the earth in their areas at the time of impact, they are geochemically dissimilar from volcanic materials.
Since in all the above-mentioned mires silicate spherules were detected only in one layer, we proposed a new precise correlation method for Holocene sequences, based on these microimpactites.
A case of coccidioidomycosis was defined as one in which the diagnosis could be corroborated by positive coccidioidal serologic results, fungal culture, or histologic identification of spherules in biopsy specimens.
Although the spherules could have come from volcanoes, the droplets' widespread distribution and mineral composition suggest they condensed from a cloud of rock vapor blasted into and above the atmosphere after a massive impact.
2) Spherules and endospores may be detected in tissues on hematoxylin-eosin-stained slides and with Gomori methenamine silver staining, or in cytologic specimens.
The spherules were created when asteroids crashed into the Earth, vaporizing rock that expanded into space as a giant vapour plume.
immitis spherule morphology and clearly formed a biofilm on the surface of the tubing.
Keller and her colleagues also dispute the theory that huge, impact-generated waves deposited the layers of disturbed sediments above the spherule bed.
A killed whole spherule vaccine that showed promise in animal trials was not well tolerated in humans (13).
When released from the spherule, each endospore can act as a new infectious unit in vivo (1).
The primary cell or spherule is known as the theca, and the appearance of the autospherulating theca has been termed mulberry-like endosporulation,[1] morula,[2] and frambasiform.