Disturbances of karyokinesis and its relation to the nuclear pattern

Cardiac stem cells and mechanisms of myocardial regeneration

This review discusses current understanding of the role that endogenous and exogenous progenitor cells may have in the treatment of the diseased heart. In the last several years, a major effort has been made in an attempt to identify immature cells capable of differentiating into cell lineages different from the organ of origin to be employed for the regeneration of the damaged heart. Embryonic stem cells (ESCs) and bone marrow-derived cells (BMCs) have been extensively studied and characterized, and dramatic advances have been made in the clinical application of BMCs in heart failure of ischemic and nonischemic origin. However, a controversy exists concerning the ability of BMCs to acquire cardiac cell lineages and reconstitute the myocardium lost after infarction. The recognition that the adult heart possesses a stem cell compartment that can regenerate myocytes and coronary vessels has raised the unique possibility to rebuild dead myocardium after infarction, to repopulate the hypertrophic decompensated heart with new better functioning myocytes and vascular structures, and, perhaps, to reverse ventricular dilation and wall thinning. Cardiac stem cells may become the most important cell for cardiac repair.

A flow cytofluorometric study on age-dependent ploidy class changes in mouse hepatocyte nuclei

To quantitate the age-dependent hyperploidization of mouse hepatic cell nuclei, a cytophotometric study using FACS III was performed. The isolated nuclei from the liver of C57BL/6CrSlc mice at various ages were stained with chromomycin A3. The fraction of polyploid nuclei was increased with age and invariably greater in male than in female animals of corresponding ages. The highest ploidy class observed was 16C, but from the analysis of polyploidization ratio, increase in 4C and 8C nuclei was considered to be the characteristic of the age-related change.