title: In vivo response to the different LET regions of a 55 MeV helium ion beam.
abstract: We evaluated the in vivo response to heavy particle irradiation in rat tail epidermis using silver-stained nucleolar organizer regions (AgNOR) as the end-point. The energy degradation of the beam across the circular section of the tail allowed us to study the damage elicited by two different LET regions of a helium beam, i.e. non-Bragg peak (NBP) and Bragg peak (BP), at different sites on the same sample. The tails were locally irradiated with a helium ion beam at different fluences. AgNOR exhibited marked variations between tissue areas only a few micrometers apart within each tail exposed to a given beam fluence. An analysis of the AgNOR variations in NBP and BP areas of tails exposed to different beam fluences revealed a dose-dependent effect. The AgNOR provide quantitative evidence of differential damage in neighboring tissue areas exposed to different LET regions of a helium-ion beam.
authors.affiliation: Department of Oral Pathology, Faculty of Dentistry University of Buenos Aires, Marcelo T. de Alvear 2142, (1122), Buenos Aires, Argentina.
authors.forename: M E
authors.initials: ME
authors.lastname: Itoiz
authors.forename: B
authors.initials: B
authors.lastname: Molinari
authors.forename: O
authors.initials: O
authors.lastname: Bernaola
authors.forename: E L
authors.initials: EL
authors.lastname: Kreimann
authors.forename: G
authors.initials: G
authors.lastname: Saint-Martin
authors.forename: A E
authors.initials: AE
authors.lastname: Schwint
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D004817:Epidermis / Q000528:radiation effects; D020450:Heavy Ions; D006371:Helium; D007477:Ions; D018499:Linear Energy Transfer; D016014:Linear Models; D009697:Nucleolus Organizer Region / Q000528:radiation effects; D011882:Radiotherapy, High-Energy / Q000295:instrumentation; D051381:Rats; D017208:Rats, Wistar; D016622:Silver Staining; D013623:Tail / Q000528:radiation effects
chemical_list: D007477:Ions; D006371:Helium