In vitro tetraploidy in patients with ulcerative colitis

Hypocellular myelodysplasia

Myelodysplasia must be considered in the differential diagnosis of patients who have bone marrow failure, but bone marrow cellularity per se may not substantially affect either response to therapy or prognosis. It is unclear whether the primary pathophysiologic defect differs between hyper- and hypoplastic patients who have myelodysplasia. Cellularity does not seem to affect response to immunosuppressive therapy significantly and does not seem to be the major factor affecting improvements in response to lenalidomide, stem cell transplantation, or hematopoietic growth factors.

Human skin fibroblast in vitro tetraploidy. Flow cytometric DNA assay used to confirm metaphase assay in patients with various colonic diseases

One hundred twenty-two patients with various colon pathologies (43 colorectal carcinoma patients exclusive of the known autosomal dominant colorectal cancer syndromes, 31 patients with solitary colorectal adenomas, 27 patients with ulcerative colitis, and 21 controls with no evidence of colorectal cancer) were investigated for in vitro tetraploidy in dermal fibroblasts cultures using a metaphase assay for determination of numerical chromosomal alterations. Later, stationary cultures of these skin fibroblasts were investigated with DNA flow cytometry. There was good correlation between the percentage of tetraploid metaphase cells and the percentage of nuclei with a flow cytometric DNA index of 2. Using a linear discrimination function to classify the flow cytometric data, the peak with DNA index of 2 was the most important parameter, supplemented by the region with DNA index greater than 2, whereas the region with DNA index between 1 and 2 probably represented a different subpopulation. We have thus demonstrated that only the region with a DNA index of 2 or greater is suitable in determining in vitro tetraploidy in stationary skin fibroblast cultures.

Increased in vitro tetraploidy and mandibular osteomas in patients with and without colorectal diseases

One hundred and seventy-six individuals with various colorectal diseases were investigated simultaneously for increased in vitro tetraploidy in dermal fibroblast cultures and for occult mandibular osteomas. In only 10 of the 176 persons were both presumed markers of colorectal genetic predisposition present in the same individual. No evidence was found that these traits are causally associated. A combination of the two presumed markers showed a tendency towards occurrence in individuals with a positive family history of colorectal cancer among first-degree relatives.