Chromosomal aberrations: Aberrations are changes encountered in the chromosomes during cell division
. Although many types of aberrations are found, the more commonly observed are deletion (loss of a small segment of a chromosome usually in only one homologue) leading to loss of information, translocation (a segment of one of the two homologous chromosomes breaks and binds to the other), duplication (occurrence of the same sectors twice on the same chromosome), inversion (a particular sector is reversed in the chromosome), insertion (a new sector is inserted into the chromosome) and substitution (a certain chromosome sector is replaced with another).
The target of the drug is Plk-1 (polo-like kinase1), a protein that acts as a catalyst in cell division
Professor Premkumar Reddy, from Temple University School of Medicine in Philadelphia, USA, who led the research, said: 'Because all signalling pathways that have gone awry in a cancer cell ultimately affect cell proliferation, a reasonable approach to cancer therapy is to develop inhibitors that block the function of a critical molecule required by a tumour cell to complete cell division
. One such molecule appears to be Plk1.'
"Nevertheless, the cell division
program for eggs is extraordinarily similar in mice and humans, and the results of our studies in mice are disturbing because brief exposure during the final stages of egg growth were sufficient to cause significant increases in meiotic abnormalities."
Douglas James, general manager of EVI's Fuel Cell Division
Likewise, Mambelli and Setter (1998) have shown that an increasing concentration of ABA in maize endosperm negatively affects cell division
. Also, cytokinins have been shown to regulate cell and plastid division in plant tissue (Davies, 1987).
Team leader Dr Stephen Davis said: "We've blocked cell division
in the hair follicle and blocked the process of cell death.
It was in this way that the German botanist Eduard Adolf Strasburger (1844-1912) was able to observe some of the changes that took place during cell division
A: When carcinogens or viruses activate a cell's cancer-producing oncogenes, those genes start making proteins, many of which are enzymes that control cell division
. When the enzymes are overproduced and underregulated, the cell starts proliferating.
Vernon and Hicks (1980, pp.529-534), reporting on the handicapping conditions associated with the neurological damage referred to above, cite the reduction of cell division
in the embryo, the failure of whatever systems have not already matured in the foetus when the rubella strikes, and the continued inflammation (usually from six to eighteen months postnatally but in some rare cases up to 29 years) with its attendant cell damage.
Before cell division
, the long strings of the cell's DNA are wrapped tightly into the structures we know as chromosomes.