Document Detail

An analysis of particle track effects on solid mammalian tissues.
MedLine Citation:
PMID:  11681323     Owner:  NASA     Status:  MEDLINE    
Relative biological effectiveness (RBE) and quality factor (Q) at extreme values of linear energy transfer (LET) have been determined on the basis of experiments with single-cell systems and specific tissue responses. In typical single-cell systems, each heavy particle (Ar or Fe) passes through a single cell or no cell. In experiments on animal tissues, however, each heavy particle passes through several cells, and the LET can exceed 200 keV micrometers-1 in every cell. In most laboratory animal tissue systems, however, only a small portion of the hit cells are capable of expressing the end-point being measured, such as cell killing, mutation or carcinogenesis. The following question was therefore addressed: do RBEs and Q factors derived from single-cell experiments properly account for the damage at high LET when multiple cells are hit by HZE tracks? A review is offered in which measured radiation effects and known tissue properties are combined to estimate on the one hand, the number of cells at risk, p3n, per track, where n is the number of cells per track based on tissue and organ geometry, and p3 is the probability that a cell in the track is capable of expressing the experimental end-point. On the other hand, the tissue and single-cell responses are compared by determining the ratio RBE in tissue/RBE in corresponding single cells. Experimental data from the literature indicate that tissue RBEs at very high LET (Fe and Ar ions) are higher than corresponding single-cell RBEs, especially in tissues in which p3n is high.
P Todd
Related Documents :
3555773 - Inhibition of growth and induction of differentiation in a malignant human glioma cell ...
20237903 - Alternative sources of adult stem cells: human amniotic membrane.
17465883 - Does thioredoxin-1 prevent mitochondria- and endoplasmic reticulum-mediated neurotoxici...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, U.S. Gov't, Non-P.H.S.; Review    
Journal Detail:
Title:  International Journal Of Radiation Applications And Instrumentation. Part D, Nuclear Tracks And Radiation Measurements     Volume:  20     ISSN:  0735-245X     ISO Abbreviation:  Int J Rad Appl Instrum D     Publication Date:  1992  
Date Detail:
Created Date:  2001-10-26     Completed Date:  2001-12-07     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  9882025     Medline TA:  Int J Rad Appl Instrum D     Country:  United States    
Other Details:
Languages:  eng     Pagination:  241-6     Citation Subset:  S    
2595 Vassar Drive, Boulder, CO 80303, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bone and Bones / cytology,  radiation effects
Cells / radiation effects*
Cells, Cultured
Cosmic Radiation*
Culture Techniques
Jejunum / cytology,  radiation effects
Linear Energy Transfer*
Radiation Tolerance*
Relative Biological Effectiveness
Scattering, Radiation
Testis / cytology,  radiation effects
T W Clarkson / U Rochester, NY

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Motor unit properties after operant conditioning of rat H-reflex.
Next Document:  Ultrastructural analyses of somatic embryo initiation, development and polarity establishment from m...