Isomorphic biphasic algal life cycles often occur in the environment at ploidy abundance ratios (Haploid:Diploid) different from 1. Its spatial variability occurs within populations related to intertidal height and hydrodynamic stress, possibly reflecting the niche partitioning driven by their diverging adaptation to the environment argued necessary for their prevalence (evolutionary stability)...

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...

We have established a murine model and techniques with which to serially study thrombocytopoiesis after induction of experimental immune thrombocytopenia of variable severity and duration. Bone marrow megakaryocyte ploidy distribution was determined by using unfractionated bone marrow, a polyclonal megakaryocyte-specific probe, and two-color, fluorescence-activated flow cytometry. With these te...

to investigate the patterns of dna ploidy and proliferating activity in breast cancer and relate them to other prognostic factors, paraffin blocks of 53 cases of breast carcinoma were studied. cancer cells obtained by mechanical tissue disaggregation were examined for dna content, ploidy and s-phase fraction. dna assay was done using a cas interactive image analyzing system. all of the cases sh...

neuroblastoma, one of the common malignant childhood tumors, arises from neuroblast cells derived from theneural crest and destined for the adrenal medulla and the sympathetic nervous system and shows remarkable biologicalheterogeneity, resulting in favorable or unfavorable outcomes. some tumors make rapid progress with a fataloutcome. in other instances, the tumors regress spontaneously in inf...

Characterizing phenotypic differences between sexual and asexual organisms is a critical step towards understanding why sexual reproduction is so common. Because asexuals are often polyploid, understanding how ploidy influences phenotype is directly relevant to the study of sex and will provide key insights into the evolution of ploidy-level variation. The well-established association between g...

Polyploidy is considered to be a major source of genetic diversity in plants. Genome duplication has been shown repeatedly to be associated with changes in biotic interactions, but little is known about whether species traits such as herbivore resistance consistently change with increasing ploidy level among closely related plant species. We tested whether larval survival and performance of the...