Biomaterial Database

Microdosimetry of haemopoietic stem cells irradiated by alpha particles from the short-lived products of 222Rn decays in fat cells and haemopoietic tissue. 1996

D E Charlton, and T D Utteridge, and A H Beddoe

Physics Department, Concordia University, Montreal, Quebec, Canada.

The Monte Carlo method is used to model fat cells and the nuclei of stem cells in haemopoietic tissue where 222Rn is dissolved in different amounts in the fat and tissue. Calculations are performed for fat cells of diameters 50 and 100 microns and for stem cell nuclei of 8 and 16 microns diameters for various fractions of fat filling the volume. Average doses (and their distributions) to stem cell nuclei from single passages of alpha particles are presented. In addition to dose, the relationship between LET and dose is obtained, illustrating the importance of 'stoppers' in the calculations. The annual average dose equivalent for a concentration of 1 Bq/m3 in air agrees well with other authors at 12 mu Sv/year. The method also allows the calculation of the fraction of stem cell nuclei hit annually. Here for 1 Bq/m3, stem cell nuclei of diameter 8 microns and 100% fat filing 15 x 10(-7) of the stem cell nuclei are hit.

UI	MeSH Term	Description	Entries
D011886	Radon	A naturally radioactive element with atomic symbol Rn, and atomic number 86. It is a member of the noble gas family found in soil, and is released during the decay of RADIUM.	Actinon,Thoron (Element)
D004307	Dose-Response Relationship, Radiation	The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.	Dose Response Relationship, Radiation,Dose-Response Relationships, Radiation,Radiation Dose-Response Relationship,Radiation Dose-Response Relationships,Relationship, Radiation Dose-Response,Relationships, Radiation Dose-Response
D006412	Hematopoietic Stem Cells	Progenitor cells from which all blood cells derived. They are found primarily in the bone marrow and also in small numbers in the peripheral blood.	Colony-Forming Units, Hematopoietic,Progenitor Cells, Hematopoietic,Stem Cells, Hematopoietic,Hematopoietic Progenitor Cells,Cell, Hematopoietic Progenitor,Cell, Hematopoietic Stem,Cells, Hematopoietic Progenitor,Cells, Hematopoietic Stem,Colony Forming Units, Hematopoietic,Colony-Forming Unit, Hematopoietic,Hematopoietic Colony-Forming Unit,Hematopoietic Colony-Forming Units,Hematopoietic Progenitor Cell,Hematopoietic Stem Cell,Progenitor Cell, Hematopoietic,Stem Cell, Hematopoietic,Unit, Hematopoietic Colony-Forming,Units, Hematopoietic Colony-Forming
D000512	Alpha Particles	Positively charged particles composed of two protons and two NEUTRONS, i.e. equivalent to HELIUM nuclei, which are emitted during disintegration of heavy ISOTOPES. Alpha rays have very strong ionizing power, but weak penetrability.	Alpha Rays,Alpha Radiation,Radiation, Alpha,Alpha Particle,Alpha Ray,Particle, Alpha,Particles, Alpha,Ray, Alpha,Rays, Alpha
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D017667	Adipocytes	Cells in the body that store FATS, usually in the form of TRIGLYCERIDES. WHITE ADIPOCYTES are the predominant type and found mostly in the abdominal cavity and subcutaneous tissue. BROWN ADIPOCYTES are thermogenic cells that can be found in newborns of some species and hibernating mammals.	Fat Cells,Lipocytes,Adipocyte,Cell, Fat,Cells, Fat,Fat Cell,Lipocyte
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus
D018499	Linear Energy Transfer	Rate of energy dissipation along the path of charged particles. In radiobiology and health physics, exposure is measured in kiloelectron volts per micrometer of tissue (keV/micrometer T).	Energy Transfer, Linear,LET,Transfer, Linear Energy