Page 289 - 2014 Printable Abstract Book
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observe strand break behavior possibly indicative of protection of guanine (G) bases when flanked by
pyrimidines, and sensitization of guanine to strand break when flanked by adenine bases in both isolated
G and GGG cases. Each of these observations provide insight into the strand break behavior in telomeric
regions due to direct-type radiation damage and in addition, could be indicative of charge transport
behavior in duplex DNA.
(PS5-04) Safety and Optimization of Radiation Sterilization in Tissue Banking: Studies on functional
1
properties of irradiated tissue grafts (IAEA CRP E31006, 2010-2014). Jan Wondergem, PhD ; Oleg
2
2
1
Belyakov, PhD ; and Eduardo Rosenblatt, MD ; LUMC, 2300 RC Leiden, Netherlands and IAEA, Vienna,
2
Austria
Introduction: The use of tissue allografts in surgical procedures has increased tremendously over
the last several years. Radiation has been used to sterilize tissue allografts on a large scale. Controversies
exist regarding the optimal dosage required since radiation may also compromise tissue allograft integrity
and/or its biological function. Tissue banks use radiation doses just based on empirical and/or historical
data, or use a fixed dose of 15 or 25 kGy for all tissue allografts. Moreover, radiation conditions differ very
strongly from institute to institute which may strongly influence the efficacy of the radiation treatment.
In order to improve the knowledge on radiosterilization of tissue allografts “new” and additional studies
were designed and conducted under controlled and validated conditions. This “new knowledge” will lead
to an optimization of the radiation sterilization process/procedures. From 2010 till 2014 the International
Atomic Energy Agency is running a Coordinated Research Project (CRP) on radiation sterilization of tissue
allografts. Five main categories of research topics were studied: Bone, Demineralized bone, Cartilage
allograft, Skin and Amnion. Results: Bone: Adoption of sterilization doses below 15 kGy improves tissue
quality and surgical outcomes. Demineralized bone (DMB): Sufficient Osteo-induction was observed after
experiments using DBM treated at 15 kGy radiation dose. Cartilage: The present studies demonstrated
that Optical Coherence Tomography (OCT) is a suitable non-destructive technique to evaluate the changes
in costal cartilage after sterilisation by ionizing radiation. Skin&Amnion: Most sensitive tissue to structural
changes induced by radiation proved to be animal skin, least sensitive human skin. In contrast to amnion,
irradiation dose up to 25kGy had minor impact on the ultrastructure of the irradiated skin its functionality
(evaporation index). Conclusion: It can be concluded that since 2010 significant progress has been made
by the participating tissue banks/institutes leading to the production of safer allografts both with respect
to its functionality and sterility.
(PS5-05) Quantification of electron induced desorption and polymerisation in thins films of thymine and
thymidine. Pierre-Olivier Lahaie, B.Sc. Physics; Andrew D. Bass, PhD; Léon Sanche, PhD; and Michael A.
Huels, PhD; Université de Sherbrooke, Sherbrooke, Canada
Low energy electrons (with E < 50 eV) play an important role in radiation induced damage to DNA.
Various species created by the reactions of LEE with DNA can be identified by liquid chromatography
(HPLC) analysis of LEE irradiated short oligonucleotide samples. Measurement of both the loss of un-
damaged parent molecules and the formation of new radiation products, has allowed damage pathways,
such as electron transfer, to be identified (Z. Li et al, JACS, 132, 15, 2010). However, this experimental
method could not account for some 70% of the observed loss of undamaged DNA, which represented 6%
287 | P a g e
pyrimidines, and sensitization of guanine to strand break when flanked by adenine bases in both isolated
G and GGG cases. Each of these observations provide insight into the strand break behavior in telomeric
regions due to direct-type radiation damage and in addition, could be indicative of charge transport
behavior in duplex DNA.
(PS5-04) Safety and Optimization of Radiation Sterilization in Tissue Banking: Studies on functional
1
properties of irradiated tissue grafts (IAEA CRP E31006, 2010-2014). Jan Wondergem, PhD ; Oleg
2
2
1
Belyakov, PhD ; and Eduardo Rosenblatt, MD ; LUMC, 2300 RC Leiden, Netherlands and IAEA, Vienna,
2
Austria
Introduction: The use of tissue allografts in surgical procedures has increased tremendously over
the last several years. Radiation has been used to sterilize tissue allografts on a large scale. Controversies
exist regarding the optimal dosage required since radiation may also compromise tissue allograft integrity
and/or its biological function. Tissue banks use radiation doses just based on empirical and/or historical
data, or use a fixed dose of 15 or 25 kGy for all tissue allografts. Moreover, radiation conditions differ very
strongly from institute to institute which may strongly influence the efficacy of the radiation treatment.
In order to improve the knowledge on radiosterilization of tissue allografts “new” and additional studies
were designed and conducted under controlled and validated conditions. This “new knowledge” will lead
to an optimization of the radiation sterilization process/procedures. From 2010 till 2014 the International
Atomic Energy Agency is running a Coordinated Research Project (CRP) on radiation sterilization of tissue
allografts. Five main categories of research topics were studied: Bone, Demineralized bone, Cartilage
allograft, Skin and Amnion. Results: Bone: Adoption of sterilization doses below 15 kGy improves tissue
quality and surgical outcomes. Demineralized bone (DMB): Sufficient Osteo-induction was observed after
experiments using DBM treated at 15 kGy radiation dose. Cartilage: The present studies demonstrated
that Optical Coherence Tomography (OCT) is a suitable non-destructive technique to evaluate the changes
in costal cartilage after sterilisation by ionizing radiation. Skin&Amnion: Most sensitive tissue to structural
changes induced by radiation proved to be animal skin, least sensitive human skin. In contrast to amnion,
irradiation dose up to 25kGy had minor impact on the ultrastructure of the irradiated skin its functionality
(evaporation index). Conclusion: It can be concluded that since 2010 significant progress has been made
by the participating tissue banks/institutes leading to the production of safer allografts both with respect
to its functionality and sterility.
(PS5-05) Quantification of electron induced desorption and polymerisation in thins films of thymine and
thymidine. Pierre-Olivier Lahaie, B.Sc. Physics; Andrew D. Bass, PhD; Léon Sanche, PhD; and Michael A.
Huels, PhD; Université de Sherbrooke, Sherbrooke, Canada
Low energy electrons (with E < 50 eV) play an important role in radiation induced damage to DNA.
Various species created by the reactions of LEE with DNA can be identified by liquid chromatography
(HPLC) analysis of LEE irradiated short oligonucleotide samples. Measurement of both the loss of un-
damaged parent molecules and the formation of new radiation products, has allowed damage pathways,
such as electron transfer, to be identified (Z. Li et al, JACS, 132, 15, 2010). However, this experimental
method could not account for some 70% of the observed loss of undamaged DNA, which represented 6%
287 | P a g e
