Image cytometric DNA measurements provide data which are most often interpreted as equivalent to the chromosomal ploidy although the chromosomal and the DNA ploidy are not identical. The common link between them is the cell cycle. Therefore, if destined for DNA ploidy interpretations, the DNA cytometry should be performed on a population-oriented stochastic basis. Using stochastic sampling the ...

BACKGROUND DNA cytometry is a technique that allows densitometric analysis of nuclear DNA of cells and in this way the evaluation of DNA ploidy. OBJECTIVE The purpose of the present study was the evaluation of DNA ploidy in oral leukoplakia and oral lichen planus and correlation with histological dysplasia. METHODS We analyzed oral incisional biopsies from a group of 40 patients with oral l...

It is well known that DNA-ploidy is useful independent prognosticator of malignancy. However, the biological significance of polyploid cells and the relation between polyploidy and prognosis is not well understood. We analyzed DNA ploidy by flow cytometry in Meth-A cells (a cultured sarcoma cell line) after treatment with K252a, a protein kinase inhibitor, and showed induction of polyploidizati...

The formation of symbiotic nodule cells in Medicago truncatula is driven by successive endoreduplication cycles and transcriptional reprogramming in different temporal waves including the activation of more than 600 cysteine-rich NCR genes expressed only in nodules. We show here that the transcriptional waves correlate with growing ploidy levels and have investigated how the epigenome changes d...

To study intratumoral DNA ploidy heterogeneity and S-phase fraction (SPF) variability, we prospectively collected five different samples from 48 breast carcinomas and each sample was analysed separately by flow cytometry. Aneuploidy rate was 89.6% after analysis of four or five samples. DNA ploidy heterogeneity, i.e., different samples classified as either DNA euploid or DNA aneuploid in the sa...

Ploidy studies of tumors are a diagnostic and prognostic aid. The aim of the present study was to evaluate the DNA content of palate aggressive pleomorphic adenomas (PA) and adenocarcinomas of the salivary glands. Twelve cases of salivary gland tumors of the palate were selected from the archives of the Oral Pathology Department, Faculty of Dentistry, University of Buenos Aires (1966-2001). Six...

In gynecologic oncology valid prognostic factors are necessary to estimate the course of disease and to define biologically similar subgroups for analysis of therapeutic efficacy. The presented study is a prospective study concerning prognostic significance of DNA ploidy and S-phase fraction in breast cancer following enrichment of tumor cells by cytokeratin labelling. Epithelial cells were lab...

The Achillea millefolium aggregate is one of the most diverse polyploid complexes of the Northern hemisphere and has its western Eurasian boundary in the Iberian Peninsula. Four ploidy levels have been detected in A. millefolium, three of which have already been found in Iberia (diploid, hexaploid and octoploid), and a fourth (tetraploid) reported during the preparation of this paper. We collec...

Prognostic value of DNA-ploidy in gastric cancers is still a matter of controversy. A possible explanation for the discrepant results reported in the literature could be sampling error in tumours with multiple stemlines differing in DNA-ploidy [2,4]. In order to determine whether or not such hetero-geneity exists and play a role in biology of gastric cancers we have analysed two different types...

Ploidy level is important in biodiversity studies and in developing strategies for isolating important plant genes. Many herbicide-resistant weed species are polyploids, but our understanding of these polyploid weeds is limited. Japanese foxtail, a noxious agricultural grass weed, has evolved herbicide resistance. However, most studies on this weed have ignored the fact that there are multiple ...