A Further Study on the Incidence of Nucleoli in Myeloblasts of Patients Suffering from Acute Myeloid Leukemia

Technical Note Cell Dysplasia - Cell Dysplastic Features (A Morphological Note)

Cell dysplasia is a currently used term describing various cellular developmental abnormalities visible by microscopy. However, detailed description of these developmental abnormalities might provide useful information not only on the cell state but also on the abnormal developmental steps of cell lineages, tissues and organs. The frequently noted visualized cell dysplastic features reflect nuclear- or nucleolar-cytoplasmic anarchy (asynchrony), premature heterochromatin condensation state, marked aneuploidy, abnormal nucleus-cytoplasm ratio, abnormality of cell organelles including mitochondria, abnormal presence or absence of cell lineage-specific granules, and formation of peripheral buds or blebbing on the cell surface. The description of these frequently occurring cell dysplastic features might also be helpful in recognizing and studying defined specific disorders of the "whole macro-body" expressed as a disease.

Nucleolar asynchrony observed in HL-60 leukemic granulocytic precursors resistant to 5-aminolaevulinic acid-based photodynamic treatment

To provide more information on the 5-aminolaevulinic acid (ALA)-induced photodynamic effect on nucleoli, morphologically expressed nucleolar asynchrony (the presence of 'active' large nucleoli with an uniform distribution of RNA and 'resting' ring-shaped nucleoli in one and the same nucleus) was studied in cultured HL-60 leukemic granulocytic precursors using a simple cytochemical procedure for the demonstration of RNA. Nucleolar asynchrony was mainly expressed in cells which were apparently resistant to ALA-based photodynamic treatment (PDT) since most of them (about 75%) exhibited this phenomenon.

The Number of Nucleoli and Main Nucleolar Types in Lymphoblasts of Children Suffering from Acute Lymphoid Leukemia

Nucleoli were studied in lymphoblasts of children (untreated with cytostatic therapy) suffering from acute lymphoblastic leukemias (ALL) by means of a simple cytochemical procedure for the demonstration of RNA to provide information on the incidence of the main nucleolar types and the number of nucleoli in these cells. The values of the nucleolar coefficient reflecting the number of nucleoli per lymphoblast ranged between 1.66 and 2.03. The slightly larger values of the nucleolar coefficient in T-ALL were not statistically significant in comparison with those in nonT-ALL. Lymphoblasts in the bone marrow as well as the peripheral blood of both nonT and T-ALL patients mostly contained, "active" (RNA transcribing) large nucleoli with a relatively uniform distribution of RNA. "Inactive" micronucleoli or particularly "resting" ring shaped nucleoli were noted less frequently in these cells. On the other hand, the larger percentage of lymphoblasts determined in specimens stained with the panoptic staining (May-Grünwald-Giemsa) in comparison with that of lymphoblasts with "active nucleoli" in specimens stained for RNA apparently indicates the absence of such nucleoli in some of these cells. These cells might represent ageing, not proliferating, cells the existence of which has been already suggested by previous studies based on a different methodical approach.