myeloblast


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Related to myeloblast: myeloblastic leukemia

myeloblast

 [mi´ĕ-lo-blast″]
an immature cell of bone marrow, not normally found in peripheral blood; it is the most primitive precursor in the granulocytic series, which develops into the promyelocyte and eventually into a granulocyte.

my·e·lo·blast

(mī'ĕ-lō-blast),
An immature cell (10-18 mcm in diameter) in the granulocytic series, occurring normally in bone marrow, but not in the circulating blood (except in certain diseases). When stained with the usual dyes, the cytoplasm is light blue, nongranular, and variable in amount, sometimes being only a thin rim around the nucleus; the latter is deep purple-blue with finely divided, punctate, threadlike chromatin that is somewhat condensed at the periphery. A few light blue nucleoli are usually present in the nucleus, and these generally disappear as the myeloblast matures into a promyelocyte and then a myelocyte. Myeloblasts ordinarily yield a negative reaction with peroxidase.
[myelo- + G. blastos, germ]

myeloblast

/my·elo·blast/ (mi´ĕ-lo-blast″) an immature cell found in the bone marrow and not normally in the peripheral blood; it is the most primitive precursor in the granulocytic series, which matures to develop into the promyelocyte and eventually the granular leukocyte.myeloblas´tic

myeloblast

(mī′ə-lə-blăst′)
n.
An immature cell of the bone marrow that is the precursor of a myelocyte.

my′e·lo·blas′tic adj.

myeloblast

[mī′əlōblast′]
Etymology: Gk, myelos + blastos, germ
earliest recognizable precursor of the granulocytic leukocytes. The cytoplasm appears light blue, scanty, and nongranular when seen in a stained blood film. The nucleus contains distinct chromatin material in strands, together with several nucleoli. In certain leukemias a marked increase in myeloblasts is observed in the marrow and in the peripheral blood. Compare megaloblast, myelocyte, normoblast. myeloblastic, adj.
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Myeloblast

my·e·lo·blast

(mī'ĕ-lō-blast)
An immature cell in the granulocytic series, occurring normally in bone marrow but not in the blood. When stained, the cytoplasm is light blue and variable in amount; the nucleus deep purple-blue with finely divided, punctate, threadlike chromatin. A few light blue nucleoli in the nucleus generally disappear as the myeloblast matures into a promyelocyte and then a myelocyte.
[myelo- + G. blastos, germ]

myeloblast

The bone marrow cell from which the whole series of granular white blood cells (GRANULOCYTES) derives. Up to 3% of bone marrow cells are myeloblasts.

myeloblast

an immature cell of bone marrow, not normally found in peripheral blood; it is the most primitive precursor in the granulocytic series, which develops into the promyelocyte and eventually into a granulocyte.
References in periodicals archive ?
Increased eosinophilic myelocytes and myeloblasts have been interpreted as eosinophilic leukemia,[20,21] and a valuable prognostic grading system has been described by Schooley.
The immature form consists of mixtures of myeloblasts and promyelocytes while the differentiated form contains promyelocytes and more mature forms.
Preliminary results from the trial show that patients with relapsed, refractory acute myeloid leukemia (AML) experienced a decrease in peripheral blood myeloblasts, a measure of clinical activity.
10) During the blast crisis the majority of blasts are myeloblasts, but one-third may have a lymphoid morphology, usually early B-cell markers.
Bone marrow biopsy 14 days after induction of treatment revealed persistent myeloblasts and mast cell infiltrate requiring a second course of therapy with 5 days of high-dose Ara-C (1 g/[m.
Neoplastic basophils and myeloblasts in acute myeloid leukemia can have similar features, complicating the correct identification of the cell lineage.
FAB subtype M4 and M5 morphology, and the presence of myeloblasts with high-level expression of CD4 were reported to be factors that predispose to the development of GS [15].
Eight of these ten patients experienced at least a 50% reduction in circulating myeloblasts following administration of XL999, one of whom achieved a partial response.
CD13 is expressed on approximately 25% of monocytes; CD33 is expressed by myeloblasts, promyelocytes, myelocytes, and mast cells, and throughout monocyte differentiation; and HLA-DR is positive in a myeloblastic population.
The expression of this gene is even higher in the myeloblasts of Down syndrome patients with leukemia: 12-fold higher than in non-Down syndrome individuals (7).
As a measure of clinical activity, five of the 12 AML patients, or 42%, had a decrease in peripheral blood myeloblasts while both of the MDS patients experienced stable disease.
Flow cytometry studies performed on the bone marrow aspirate found increased eosinophils (19%) with no increase in myeloblasts (3%) or hematogones (2%).