BACKGROUND AND AIMS Polyploidy is viewed as an important mechanism of sympatric speciation, but only a few studies have documented patterns of distribution and ecology of different cytotypes in their contact zone. Aster amellus agg. (Asteraceae) is one of the species with documented multiple ploidy levels. The aim of this study was to determine spatial distribution and ecology of two cytotypes,...

Nucleotypic effects are phenotypic changes related to the total nuclear DNA amount per cell. These effects are commonly observed among and within genera for certain cell types, and the generality of the positive correlation between genome size and cell size has been well established. However, there are few studies of nucleotypic effects which incorporate into the analysis both ploidy level and ...

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...

The liquid-based cytology (ThinPrep) is an alternative to the long-used conventional cytology that received Food and Drug Administration approval in 1996. The purpose of the current study was to determine the diagnostic cytomorphologic criteria of ThinPrep cytology and a comparison of the accuracy of conventional and ThinPrep cytology in investigation of patients with epithelial ovarian cancer....

Comparisons of 2x, 3x, and 4X sugarbeet (Beta vulgaris L.) lines and hybrids were made to determine the effects of ploidy level on sucrose yield and quality components in equivalent and non-equivalent hybrid populations. The relative order of importance for the components of recoverable sucrose was generally the same for all three ploidy levels, with root weight having the greatest path coeffic...

Evolutionary chromosome change involves significant variation in DNA amount in diploids and genome downsizing in polyploids. Genome size and karyotype parameters of Hippeastrum species with different ploidy level were analysed. In Hippeastrum, polyploid species show less DNA content per basic genome than diploid species. The rate of variation is lower at higher ploidy levels. All the species ha...

In order to clarify the relationship between polyploidization and the capability of phenotypic switching in the imperfect yeast Candida albicans, two types of variants were isolated as segregants from a fusant, which produced a proportion of the cell population with a higher ploidy than the rest, either in a temperature-dependent or -independent manner, when incubated at low (28 degrees C) and ...

Despite numerous studies investigating the action of c-mpl ligand, no reports have defined the in vivo changes in megakaryocytopoiesis in response to a single injection of this cytokine. Here we compare the kinetics of the megakaryocytopoietic response in C57BI/6J mice administered 25 micrograms/ kg or 250 micrograms/kg of pegylated (PEG) murine megakaryocyte growth and development factor (MGDF...

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...