| 11. |
- Bivehed, Erik, et al.
(författare)
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Visualizing DNA single- and double-strand breaks in the Flash comet assay by DNA polymerase-assisted end-labelling
- 2024
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Ingår i: Nucleic Acids Research. - : Oxford University Press. - 0305-1048 .- 1362-4962. ; 52:4
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Tidskriftsartikel (refereegranskat)abstract
- In the comet assay, tails are formed after single-cell gel electrophoresis if the cells have been exposed to genotoxic agents. These tails include a mixture of both DNA single-strand breaks (SSBs) and double-strand breaks (DSBs). However, these two types of strand breaks cannot be distinguished using comet assay protocols with conventional DNA stains. Since DSBs are more problematic for the cells, it would be useful if the SSBs and DSBs could be differentially identified in the same comet. In order to be able to distinguish between SSBs and DSBs, we designed a protocol for polymerase-assisted DNA damage analysis (PADDA) to be used in combination with the Flash comet protocol, or on fixed cells. By using DNA polymerase I to label SSBs and terminal deoxynucleotidyl transferase to label DSBs with fluorophore-labelled nucleotides. Herein, TK6-cells or HaCat cells were exposed to either hydrogen peroxide (H2O2), ionising radiation (X-rays) or DNA cutting enzymes, and then subjected to a comet protocol followed by PADDA. PADDA offers a wider detection range, unveiling previously undetected DNA strand breaks. Graphical Abstract
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| 12. |
- Blomgren, Jan, et al.
(författare)
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Progress in Dosimetry of Neutrons and Light Nuclei
- 2007
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Ingår i: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 126:1-4, s. 1-2
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Forskningsöversikt (övrigt vetenskapligt/konstnärligt)
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Buratovic, Sonja, et al.
(författare)
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Developmental effects of fractionated low-dose exposure to gamma radiation on behaviour and susceptibility of the cholinergic system in mice
- 2016
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Ingår i: International Journal of Radiation Biology. - : Informa UK Limited. - 0955-3002 .- 1362-3095. ; 92:7, s. 371-379
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To investigate whether neonatal exposure to fractionated external gamma radiation and co-exposure to radiation and nicotine can affect/exacerbate developmental neurotoxic effects, including altered behavior/cognitive function and the susceptibility of the cholinergic system in adult male mice. Materials and methods: Neonatal male Naval Medical Research Institute (NMRI) mice were irradiated with one 200 mGy fraction/day and/or exposed to nicotine (66 μg/kg b.w.) twice daily on postnatal day (PND) 10, 10–11, 10–12 or 10–13 (nicotine only). At 2 months of age the animals were tested for spontaneous behavior in a novel home environment, habituation capacity and nicotine-induced behavior. Results: Fractionated irradiation and co-exposure to radiation and nicotine on three consecutive days disrupted behavior and habituation and altered susceptibility of the cholinergic system. All observed effects were significantly more pronounced in mice co-exposed to both radiation and nicotine. Conclusions: The fractionated irradiation regime affects behavior/cognitive function in a similar manner as has previously been observed for single-dose exposures. Neonatal co-exposure to radiation and nicotine, during a critical period of brain development in general and cholinergic system development in particular, enhance these behavioral defects suggesting that the cholinergic system can be a target system for this type of developmental neurotoxic effects.
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| 17. |
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| 18. |
- Buratovic, Sonja, 1986-, et al.
(författare)
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Effects on adult cognitive function after neonatal exposure to clinically relevant doses of ionising radiation and ketamine in mice
- 2018
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Ingår i: British Journal of Anaesthesia. - : ELSEVIER SCI LTD. - 0007-0912 .- 1471-6771. ; 120:3, s. 546-554
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Tidskriftsartikel (refereegranskat)abstract
- Background: Radiological methods for screening, diagnostics and therapy are frequently used in healthcare. In infants and children, anaesthesia/sedation is often used in these situations to relieve the patients' perception of stress or pain. Both ionising radiation (IR) and ketamine have been shown to induce developmental neurotoxic effects and this study aimed to identify the combined effects of these in a murine model. Methods: Male mice were exposed to a single dose of ketamine (7.5 mg kg(-1) body weight) s.c. on postnatal day 10. One hour after ketamine exposure, mice were whole body irradiated with 50-200 mGy gamma radiation (Cs-137). Behavioural observations were performed at 2, 4 and 5 months of age. At 6 months of age, cerebral cortex and hippocampus tissue were analysed for neuroprotein levels. Results: Animals co-exposed to IR and ketamine displayed significant (P <= 0.01) lack of habituation in the spontaneous behaviour test, when compared with controls and single agent exposed mice. In the Morris Water Maze test, co-exposed animals showed significant (P <= 0.05) impaired learning and memory capacity in both the spatial acquisition task and the relearning test compared with controls and single agent exposed mice. Furthermore, in co-exposed mice a significantly (P <= 0.05) elevated level of tau protein in cerebral cortex was observed. Single agent exposure did not cause any significant effects on the investigated endpoints. Conclusion: Co-exposure to IR and ketamine can aggravate developmental neurotoxic effects at doses where the single agent exposure does not impact on the measured variables. These findings show that estimation of risk after paediatric low-dose IR exposure, based upon radiation dose alone, may underestimate the consequences for this vulnerable population.
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| 19. |
- Buratovic, Sonja, et al.
(författare)
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Exposure to a single dose of ionising radiation during brain development can cause cognitive defects and increased levels of tau in mice
- 2012
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Konferensbidrag (refereegranskat)abstract
- Ionising radiation (IR) is widely used in the medical field for treating tumours, including tumours in the central nervous system, and for imaging techniques such as computed tomography (CT). There is a lack of knowledge and increasing concern about effects and consequences from low dose exposure during critical phases of perinatal and/or neonatal brain development compared to prenatal irradiation. It is known that IR causes neurotoxicological and neurobehavioural defects in mammals. Further, an epidemiological study has suggested that low doses of IR to the human brain during infancy can have a negative effect on cognitive abilities in adulthood. The rapid brain growth spurt (BGS) occurs in humans as well as mice. In humans the BGS starts during the third trimester of pregnancy and continues throughout the first two years of life. In mouse and rat the BGS is neonatal, spanning the first 3-4 weeks of life. The BGS is characterized by maturation of axonal and dendritic outgrowth, establishment of neural connections and acquisition of many new motor and sensory abilities. By using the neonatal mouse as an animal model we are able to study the effect of IR during early periods of brain development and which consequences it has for the adult animal. Disturbances in development caused by nicotine, MeHg, PCBs and PBDEs have previously been shown to alter adult spontaneous behaviour and/or neuroprotein levels in mice.Neonatal NMRI male mice were irradiated (0; 0.35 and 0.5 Gy) at one single occasion on postnatal day 10. Mice serving as controls were placed in plastic dishes for a time-period corresponding to the irradiation. Spontaneous behaviour was tested in a novel home environment at 2- and 4-months of age and parameters observed were locomotion, rearing and total activity. Analyses of important neuroprotein levels were performed on 6-month-old control and 0.5 Gy irradiated mice.Spontaneous behaviour test (locomotion, rearing, total activity revealed a significantly deranged behaviour in 2- and 4-month old mice irradiated with 0.35 or 0.5 Gy in a dose-response related manner, when compared to controls. The behavioural alterations were manifested as a reduced activity during at the beginning of the observational period and a higher activity at the end of the observational period. Analyses of the neuroprotein tau, which in human medicine is used as a biomarker for Alzheimer’s disease, showed a significantly higher level in mice irradiated with 0.5 Gy compared to controls. This demonstrates that a single dose of gamma radiation, given at a defined critical time period during brain development, is sufficient to cause persistently reduced cognitive functions and increased levels of tau in mice.
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| 20. |
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