In patients with essential thrombocytemia characterized by thrombocytosis associated with impaired mpl expression in both platelets and megakaryocytes
, TPO was within the reference interval or increased (25-27), confirming that the TPO concentration is regulated mainly by mpl in megakaryocytes
Semiquantitative results are summarized in Table 1, morphometric and morphologic data of megakaryocytes
in Table 2, and clinical and hematologic data in Table 3.
a) Adipose tissue, acute hemorrhage and hemosiderin pigment is seen at left, and hematopoietic tissue, including megakaryocytes
, at right (100x).
Maternal ingestion of chlorothiazide diuretics or tolbutamide can have a direct cytotoxic effect on the fetal marrow megakaryocytes
The relation of thrombokinetics to bone marrow megakaryocytes
and to the size of the nucleus in polycythemia vera.
The system is exponentially more efficient in generating megakaryocytes
than previous methods," stated Shi-Jiang Lu, Ph.
24) Given the finding that regulation of platelet production under steady-state conditions is aimed at keeping the total platelet mass constant, (24) it is understandable that this can only be achieved when the megakaryocytes
produce more smaller or less larger platelets, as is reflected by the retPLTs.
In chronic alcoholic cirrhosis, the thrombocytopenia and platelet functional deficiencies may result from the toxic effects of alcohol on bone marrow megakaryocytes
Bone marrow aspirate showed slight nuclear-cytoplasmic maturational dyssynchrony in the erythroid series, small hypolobate megakaryocytes
, an orderly myeloid maturation, and rare bizarre mitotic figures.
Essential thrombocythemia is characterized by uncontrolled proliferation of myeloid lineage cells, especially megakaryocytes
, leading to the overproduction of platelets.
Histological examination revealed mature necrotic bone with multiple areas of bone marrow formation, including megakaryocytes
Platelets are fragment of the large megakaryocytes
, produced in the bone morrow under influence of thrombopoetin, a chemical made by the liver and kidney.