Blastoidea

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Blastoidea

[bla′stȯid·ē·ə]
(paleontology)
A class of extinct pelmatozoan echinoderms in the subphylum Crinozoa.

Blastoidea

 

(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.

REFERENCE

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

IU. A. ARENDT

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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.
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.
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Its primary use in the evaluation of DLBCL is to exclude the possibility of the blastoid or pleomorphic variants of mantle cell lymphoma, which may at times appear similar to DLBCL.
305) Histopathologically, blastic plasmacytoid dendritic cell neoplasm is characterized by a dense monomorphous infiltrate of blastoid cells that are positive for CD4, CD56, CD123, and T-cell leukemia/lymphoma-1 (TCL1), in the absence of T-cell (CD2, CD3), B-cell (CD20), and myelomonocytic cell lineage-specific markers (myeloperoxidase, lysozyme).
Cyclin D1negative blastoid mantle cell lymphoma identified by SOX11 expression.
49) However, mutated blastoid MCL tends to present more frequently at an earlier stage, without bone marrow involvement and with lower rates of relapse, suggesting a more-favorable clinical course.
The blastoid and pleomorphic variants could also be considered, depending on the cell size and degree of pleomorphism.