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A class of extinct pelmatozoan echinoderms in the subphylum Crinozoa.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(or sea buds), a class of extinct invertebrate animals of the phylum Echinodermata. The body of the blastoid consisted of a crown formed by a blastoid calyx, or theca, with numerous “arms,” or brachioles, and a stem. The brachioles caught particles of food, which were directed to the mouth along sulci, or grooves, running from the brachioles to the ambulacra. Under the surface of the calyx was a system of calcareous tubes (hydrospires), which probably served for breathing. Blastoidea lived in the oceans from the Silurian to the Permian period. They were numerous in the Devonian and Early Carboniferous periods in North America and in the Permian period in Indonesia and the Ural Region. More than 300 species of Blastoidea are known. Some of them are the leading fossils of the Carboniferous and Permian periods.


Osnovy paleontologii: Iglokozhie. . . . Moscow, 1964.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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Within the cervical mass, all monomorphic and blastoid cells (presumed neoplastic lymphoid cells) and few individual, nonneoplastic cells within mixed aggregates showed strong positive cytoplasmic immunoreactivity for CD3 (Fig 3B).
Loghavi et al., 2015 [24], have reported five cases of Tdt-positive B-cell neoplasms with BCL2 rearrangements and MYC rearrangements; four of these had high-grade blastoid neoplasms at presentation while the fifth case was transformed from preceding follicular lymphoma.
In this study one case was diagnosed as blastoid mantle cell lymphoma as it was reactive for CD20, CD5 and negative for CD23.
The blastoid types MCL are more aggressive than MCL and associated with a worse clinical outcome.
(** Denotes holotype, * specimen crushed.) TABLE 1 Blastoid and Crinoid fauna of the Columbus Limestone.
He concludes that if the ancient echinoderms had similar characteristics, snails would have been better off to treat blastoid and crinoids as long-term hosts rather than as prey.
Likewise, frequency of pleomorphic or blastoid morphology (8% at diagnosis; 31% at relapse) was not significantly different compared with the larger unselected series of MCL.
The pathology specimen was reviewed and showed lymphomatous involvement with sheets of medium-sized cells with blastoid morphology characterized by fine chromatin, occasional distinct nucleoli, and scant cytoplasm.
Although leukemic phase of blastoid MCL can be a difficult differential diagnosis of B-PLL, in the index case, the monomorphic population of atypical lymphocytes with characteristic morphology and immunophenotyping characteristics tilted our diagnosis in favor of B-PLL short of cyclin D1 staining and cytogenetics.
After extensive phylogenetic study involving careful character analysis, he found that the Permian survivors among blastoid echinoderms were drawn from many branches of the evolutionary tree.