OBJECTIVE Megakaryocytic cells (Mks) undergo endomitosis and become polyploid. Mk ploidy correlates with platelet production. We previously showed that nicotinamide (NIC) greatly increases Mk ploidy in cultures of human mobilized peripheral blood CD34(+) cells. This study aims to examine the generality of NIC effects, NIC's impact on Mk ultrastructure, and potential mechanisms for the increased...

Natural animal populations are rarely screened for ploidy-level variation at a scale that allows detection of potentially important aberrations of common ploidy patterns. This type of screening can be especially important for the many mixed sexual/asexual systems in which sexuals are presumed to be dioecious diploids and asexuals are assumed to be triploid and all-female. For example, elevation...

The role of ploidy—copy number of chromosomes in an organism—on cells under environmental stress is poorly understood. Variations in ploidy such as aneuploidy—deviations in copy number of chromosomes compared to an organisms base ploidy—and polyploidy—more than two sets of each chromosome—are common in cancer so it is important to understand how ploidy impacts evolution. We performed an evoluti...

To determine whether a relationship exists between DNA ploidy and the prognosis of hepatocellular carcinoma (HCC), flow cytometric DNA analysis was performed in paraffin-embedded specimens obtained from 44 patients with HCC who underwent hepatectomy. There were 26 diploid (59%) and 18 aneuploid (41%) tumors. No correlation was shown between DNA ploidy pattern and patient age, sex, liver cirrhos...