Molecular Excitations in Radiation Damage as Studied by the Radiation-Induced Luminescence of Proteins

Transmission electron microscopy has been used to study the thermal annealing of radiation induced defect clusters in polycrystalline tungsten. Specimens were taken from cylindrical tensile bars which had been irradiated to a fast (E > 1 MeV) neutron fluence of 4.2 × 1019 n/cm2 at 70°C, annealed for one hour at various temperatures in argon, and tensile tested at 240°C in helium. Foils from both the unstressed button heads and the reduced areas near the fracture were examined.Figure 1 shows typical microstructures in button head foils. In the unannealed condition, Fig. 1(a), a dispersion of fine dot clusters was present. Annealing at 435°C, Fig. 1(b), produced an apparent slight decrease in cluster concentration, but annealing at 740°C, Fig. 1(C), resulted in a noticeable densification of the clusters. Finally, annealing at 900°C and 1040°C, Figs. 1(d) and (e), caused a definite decrease in cluster concentration and led to the formation of resolvable dislocation loops.

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Molecular Hydrogen as a Potential Clinically Applicable Radioprotective Agent

International Journal of Molecular Sciences ◽

10.3390/ijms22094566 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4566

Author(s):

Shin-ichi Hirano ◽

Yusuke Ichikawa ◽

Bunpei Sato ◽

Haru Yamamoto ◽

Yoshiyasu Takefuji ◽

...

Keyword(s):

Radiation Damage ◽

Molecular Hydrogen ◽

Regulation Of Gene Expression ◽

Animal Experiments ◽

Radiation Energy ◽

Water Radiolysis ◽

Low Dose Radiation ◽

Oxidizing Power ◽

Radiation Induced ◽

Radioprotective Agent

Although ionizing radiation (radiation) is commonly used for medical diagnosis and cancer treatment, radiation-induced damages cannot be avoided. Such damages can be classified into direct and indirect damages, caused by the direct absorption of radiation energy into DNA and by free radicals, such as hydroxyl radicals (•OH), generated in the process of water radiolysis. More specifically, radiation damage concerns not only direct damages to DNA, but also secondary damages to non-DNA targets, because low-dose radiation damage is mainly caused by these indirect effects. Molecular hydrogen (H2) has the potential to be a radioprotective agent because it can selectively scavenge •OH, a reactive oxygen species with strong oxidizing power. Animal experiments and clinical trials have reported that H2 exhibits a highly safe radioprotective effect. This paper reviews previously reported radioprotective effects of H2 and discusses the mechanisms of H2, not only as an antioxidant, but also in intracellular responses including anti-inflammation, anti-apoptosis, and the regulation of gene expression. In doing so, we demonstrate the prospects of H2 as a novel and clinically applicable radioprotective agent.

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Mesenchymal Stem Cell-Derived Exosomes: Biological Function and Their Therapeutic Potential in Radiation Damage

Cells ◽

10.3390/cells10010042 ◽

2020 ◽

Vol 10 (1) ◽

pp. 42

Author(s):

Xiaoyu Pu ◽

Siyang Ma ◽

Yan Gao ◽

Tiankai Xu ◽

Pengyu Chang ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Radiation Damage ◽

Therapeutic Potential ◽

Damage Model ◽

Bioactive Substances ◽

Radiation Induced ◽

Insight Into

Radiation-induced damage is a common occurrence in cancer patients who undergo radiotherapy. In this setting, radiation-induced damage can be refractory because the regeneration responses of injured tissues or organs are not well stimulated. Mesenchymal stem cells have become ideal candidates for managing radiation-induced damage. Moreover, accumulating evidence suggests that exosomes derived from mesenchymal stem cells have a similar effect on repairing tissue damage mainly because these exosomes carry various bioactive substances, such as miRNAs, proteins and lipids, which can affect immunomodulation, angiogenesis, and cell survival and proliferation. Although the mechanisms by which mesenchymal stem cell-derived exosomes repair radiation damage have not been fully elucidated, we intend to translate their biological features into a radiation damage model and aim to provide new insight into the management of radiation damage.

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RNA protects a nucleoprotein complex against radiation damage

Acta Crystallographica Section D Structural Biology ◽

10.1107/s2059798316003351 ◽

2016 ◽

Vol 72 (5) ◽

pp. 648-657 ◽

Cited By ~ 16

Author(s):

Charles S. Bury ◽

John E. McGeehan ◽

Alfred A. Antson ◽

Ian Carmichael ◽

Markus Gerstel ◽

...

Keyword(s):

Radiation Damage ◽

Rna Binding ◽

Dose Range ◽

Protein Molecule ◽

Highly Sensitive ◽

Structure Determinations ◽

Binding Pockets ◽

Radiation Induced ◽

Damage Susceptibility ◽

Dna Complex

Radiation damage during macromolecular X-ray crystallographic data collection is still the main impediment for many macromolecular structure determinations. Even when an eventual model results from the crystallographic pipeline, the manifestations of radiation-induced structural and conformation changes, the so-called specific damage, within crystalline macromolecules can lead to false interpretations of biological mechanisms. Although this has been well characterized within protein crystals, far less is known about specific damage effects within the larger class of nucleoprotein complexes. Here, a methodology has been developed whereby per-atom density changes could be quantified with increasing dose over a wide (1.3–25.0 MGy) range and at higher resolution (1.98 Å) than the previous systematic specific damage study on a protein–DNA complex. Specific damage manifestations were determined within the largetrpRNA-binding attenuation protein (TRAP) bound to a single-stranded RNA that forms a belt around the protein. Over a large dose range, the RNA was found to be far less susceptible to radiation-induced chemical changes than the protein. The availability of two TRAP molecules in the asymmetric unit, of which only one contained bound RNA, allowed a controlled investigation into the exact role of RNA binding in protein specific damage susceptibility. The 11-fold symmetry within each TRAP ring permitted statistically significant analysis of the Glu and Asp damage patterns, with RNA binding unexpectedly being observed to protect these otherwise highly sensitive residues within the 11 RNA-binding pockets distributed around the outside of the protein molecule. Additionally, the method enabled a quantification of the reduction in radiation-induced Lys and Phe disordering upon RNA binding directly from the electron density.

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Corrigendum to ‘Atomic Origins of Radiation-induced Defects and the Role of Lamellar Interfaces in Radiation Damage of Titanium Aluminide Alloy Irradiated with Kr-ions at Elevated Temperature’ [Acta Mater. 172 (2019) 72–83]

Acta Materialia ◽

10.1016/j.actamat.2020.07.043 ◽

2020 ◽

Vol 197 ◽

pp. 122

Author(s):

Hanliang Zhu ◽

Mengjun Qin ◽

Robert Aughterson ◽

Tao Wei ◽

Gregory Lumpkin ◽

...

Keyword(s):

Elevated Temperature ◽

Radiation Damage ◽

Titanium Aluminide ◽

Titanium Aluminide Alloy ◽

Acta Mater ◽

Radiation Induced ◽

Induced Defects ◽

Lamellar Interfaces

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Structural knowledge or X-ray damage? A case study on xylose isomerase illustrating both

Journal of Synchrotron Radiation ◽

10.1107/s1600577519005599 ◽

2019 ◽

Vol 26 (4) ◽

pp. 931-944 ◽

Cited By ~ 2

Author(s):

Helena Taberman ◽

Charles S. Bury ◽

Mark J. van der Woerd ◽

Edward H. Snell ◽

Elspeth F. Garman

Keyword(s):

Reaction Mechanism ◽

Radiation Damage ◽

Xylose Isomerase ◽

Data Sets ◽

High Resolution Data ◽

X Ray ◽

Metal Cofactor ◽

Acid Environment ◽

Radiation Induced ◽

Catalytic Metal

Xylose isomerase (XI) is an industrially important metalloprotein studied for decades. Its reaction mechanism has been postulated to involve movement of the catalytic metal cofactor to several different conformations. Here, a dose-dependent approach was used to investigate the radiation damage effects on XI and their potential influence on the reaction mechanism interpreted from the X-ray derived structures. Radiation damage is still one of the major challenges for X-ray diffraction experiments and causes both global and site-specific damage. In this study, consecutive high-resolution data sets from a single XI crystal from the same wedge were collected at 100 K and the progression of radiation damage was tracked over increasing dose (0.13–3.88 MGy). The catalytic metal and its surrounding amino acid environment experience a build-up of free radicals, and the results show radiation-damage-induced structural perturbations ranging from an absolute metal positional shift to specific residue motions in the active site. The apparent metal movement is an artefact of global damage and the resulting unit-cell expansion, but residue motion appears to be driven by the dose. Understanding and identifying radiation-induced damage is an important factor in accurately interpreting the biological conclusions being drawn.

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X-ray radiation-induced amorphization of metal–organic frameworks

Physical Chemistry Chemical Physics ◽

10.1039/c9cp01463b ◽

2019 ◽

Vol 21 (23) ◽

pp. 12389-12395 ◽

Cited By ~ 8

Author(s):

Remo N. Widmer ◽

Giulio I. Lampronti ◽

Nicola Casati ◽

Stefan Farsang ◽

Thomas D. Bennett ◽

...

Keyword(s):

Radiation Damage ◽

Metal Organic Frameworks ◽

X Rays ◽

X Ray ◽

P Accumulation ◽

Metal Organic ◽

Radiation Induced ◽

Crystalline Metal

Accumulation of radiation damage from synchrotron X-rays leads to complete amorphization of the initially crystalline metal–organic frameworks ZIF-4, ZIF-62, and ZIF-zni. The mechanism of this transformation is studied as a function of time and temperature and is shown to be non-isokinetic.

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Self-Radiation Damage in Actinide Host Phases of Nuclear Waste Forms

MRS Proceedings ◽

10.1557/proc-44-679 ◽

1984 ◽

Vol 44 ◽

Cited By ~ 6

Author(s):

W. J. Weber ◽

J. W. Wald ◽

Hi. Matzke

Keyword(s):

Radiation Damage ◽

Nuclear Waste ◽

Amorphous State ◽

Alpha Decay ◽

Ceramic Materials ◽

Thermal Recovery ◽

Radiation Induced ◽

Crystalline Ceramic ◽

Higher Doses ◽

Nuclear Waste Forms

AbstractThree crystalline ceramic materials, which occur as host phases for the long-lived actinides in many nuclear waste formulations, were doped with Cm-244, and the effects of self-radiation damage from alpha decay on microstructure and physical properties were investigated. The irradiation-induced microstructure consisted of individual amorphous tracks from both the alpha-recoil particles and the spontaneous fission fragments. The eventual overlap of the tracks at higher doses leads to a completely amorphous state. This radiation-induced amorphization process results in measured increases in volume, leachability, and stored energy. Thermal recovery of the radiation-induced swelling and amorphization occurs with full recrystallization to the initial structures.

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