Experimental evidence to support the hypothesis that damage to vascular endothelium plays the primary role in the development of late radiation-induced CNS injury

ABSTRACTAtomic transport in irradiated solids has been investigated in both the prompt and delayed regimes. Prompt effects are revealed on an atomic level through molecular dynamics computer simulations. It is demonstrated that for metals like gold, which have high atomic numbers and low melting points, thermal spikes play a primary role in the cascade dynamics and that concepts like melting and rapid quenching are useful descriptions. Surface effects in these metals are also discussed. For metals with higher melting points and lower atomic numbers, the cascade dynamics are determined almost exclusively by energetic collisions far above thermal energies. This is illustrated by simulations of cascades in NiAl. The effect of the high ordering energy in this intermetallic compound on the radiation-induced defect structure has also been studied.Atomic transport in the delayed regime is illustrated by two examples: an order-disorder alloy, Cu3Au, and an amorphous alloy, NiZr. The first example is used to illustrate various aspects of radiation enhanced diffusion (RED): ion beam mixing, diffusion kinetics, the effects of primary recoil spectrum, and the importance of chemical order. The second example illustrates that the basic theory of RED, which was developed to describe crystalline materials, appears to work adequately for amorphous metal alloys, suggesting that similar mechanisms may be operating. It is shown, however, that the kinetics of RED observed in amorphous alloys are not unique to point defect models.

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Experimental evidence of Er^3+ ion reduction in the radiation-induced degradation of erbium-doped silica fibers

Optics Letters ◽

10.1364/ol.39.006154 ◽

2014 ◽

Vol 39 (21) ◽

pp. 6154 ◽

Cited By ~ 15

Author(s):

Yasmine Mebrouk ◽

Franck Mady ◽

Mourad Benabdesselam ◽

Jean-Bernard Duchez ◽

Wilfried Blanc

Keyword(s):

Experimental Evidence ◽

Silica Fibers ◽

Erbium Doped ◽

Radiation Induced

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Tumor targeted drug delivery directed to radiation-induced cell adhesion molecules in tumor vascular endothelium

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/s0360-3016(02)03103-6 ◽

2002 ◽

Vol 54 (2) ◽

pp. 27

Author(s):

L Geng ◽

S.R Konjeti ◽

H Onishko ◽

D.E Hallahan

Keyword(s):

Drug Delivery ◽

Cell Adhesion ◽

Adhesion Molecules ◽

Vascular Endothelium ◽

Targeted Drug Delivery ◽

Cell Adhesion Molecules ◽

Radiation Induced ◽

Targeted Drug

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Untersuchungen über den Mechanismus des Strahlenschutzes von Thiol- und Disulfidverbindungen am Modell biologischer Elementareinheiten

Zeitschrift für Naturforschung B ◽

10.1515/znb-1966-0211 ◽

1966 ◽

Vol 21 (2) ◽

pp. 148-152 ◽

Cited By ~ 3

Author(s):

G. Hotz

Keyword(s):

Experimental Evidence ◽

Gamma Rays ◽

Room Temperature ◽

Protective Action ◽

Protective Mechanism ◽

Experimental Conditions ◽

Phage Dna ◽

Radiation Induced

The inactivation of plaque forming ability of T 1 bacteriophage by X- and 60Co-gamma-rays was used to test the protective action of different concentrations of cysteamine and cystamine in broth-suspension, in the dry state. at 300 and at 80°K respectively. Under all experimental conditions the amount of radioprotection given by the disulfide is comparable within a few percent to the protection afforded by the thiol. The protective mechanism by which both compounds act at room temperature or at 80°K is discussed emphasizing evidence in favour of the hypothesis of electron-hydrogen donation. Oxygen reduces the efficiency of this mechanism by competing with the thiol as well as with the disulfide for radiation induced radicals in the phage DNA. Experimental evidence is given for the conclusion that cystamine needs not be reduced by enzymes or radiation to show efficient radioprotection.

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