Nucleocytoplasmic Ratio

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nucleocytoplasmic ratio

[¦nü·klē·ō‚sīd·ə′plaz·mik ′rā·shō]
(cell and molecular biology)
The ratio between the measured cross-sectional area or estimated volume of the nucleus of a cell to the volume of its cytoplasm. Also known as karyoplasmic ratio.

Nucleocytoplasmic Ratio


(also nucleoplasmic ratio), in biology, the ratio of nuclear to cytoplasmic volume. The ratio was introduced in 1908 by the German scientist R. Hertwig, who believed that regular decrease in the nucleocytoplasmic ratio was the immediate cause of the initiation of cell division. Hertwig’s hypothesis has not been confirmed. The volume of the nucleus is usually directly proportional to the volume of the cytoplasm, including the case of polyploidy of the nucleus. However, many exceptions to this proportionality are known, for example, in the development of egg cells or in changes of the functional activity of a cell. Cells of different tissues have different nucleocyto-plasmic ratios; therefore, the ratios are used to characterize cell types.

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Bone marrow aspiration was done, revealing clusters of cells, with high nucleocytoplasmic ratio, fine chromatin and two to three nucleoli.
Hypogranularity is less common whereas bizarrely shaped nuclei and a high nucleocytoplasmic ratio in mature cells are more common, but they are quite uncommon whereas they are characteristic of HIV infection.
In summary, this case illustrates that several of the key criteria used for a diagnosis of TIC can be seen in papillary syncytial metaplasia of tubal mucosal endometriosis, including marked epithelial stratification with loss of polarity, increased nucleocytoplasmic ratio, and rounded nuclei with chromatin clearing and prominent nucleoli.
The cells were cuboidal in the hyperplastic and papillary areas, with an increased nucleocytoplasmic ratio, round bland nuclei with low mitotic activity, and inconspicuous nucleoli (Figure 1).
Individual cells were uniform sized with eosinophilic cytoplasm, high nucleocytoplasmic ratio and increased mitotic activity (Figure 2).