Differential equations were used to model cellular injury, repair, and compensatory proliferation in the irradiated bone marrow. Recently, that model was implemented as MarCell, a user-friendly MS-DOS computer program that allows users from a variety of technical disciplines to evaluate complex radiation exposure. The software allows menu selections for different sources of ionizing radiation. Choices for cell lineages include progenitor, stroma, and malignant, and the available species include mouse, rat, dog, sheep, swine, burro, and man. An attractive feature is that any protracted irradiation can be compared with an equivalent prompt dose (EPD) in terms of cell kinetics for either the source used or for a reference such as 250 kVp x rays or 60Co. EPD is used to mean a dose rate for which no meaningful biological recovery occurs during the period of irradiation. For human as species, output from MarCell includes: risk of 30-day mortality; risk of whole-body cancer and leukemia based either on radiation-induced cytopenia or compensatory cell proliferation; cell survival and repopulation plots as functions of time or dose; and 4-week recovery following treatment.

Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling toxicity-induced compensatory

Investigate the existence of microsatellite instability (MSI) in patients with invasive ductal breast carcinoma (IDC). Investigate the existence of microsatellite instability (MSI) in breast cancer of patients. DNA had been extracted from frozen tissue samples of breast cancer. This protocol done according to the kit manufacture's manual of QIAamp DNA Mini kit from Qiagen -USA. All samples tested for MSI by singleplex PCR reactions using two microsatellite markers BAT 25 and BAT 26. PCR achieved in a final volume of 50 µl and after thermal cycles, gel visualization performed. PCR demonstrating microsatellite instability in 13 (26%) of the 50 breast cancer sample. Eight (16%) of 50 breast cancer sample were BAT 25 positive with a PCR product size of 124 bp, while 5 (10%) of 50 breast cancer sample were BAT 26 positive with a PCR product size 121bp. The result suggests strong evidence that microsatellite instability (MSI) at the BAT 25 and BAT 26 and have involved in the pathogenesis of the great majority of breast cancers.