Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Clustered DNA damage other than double-strand breaks (DSBs) can be detrimental to cells and can lead to mutagenesis or cell death. In addition to DSBs induced by ionizing radiation, misrepair of non-DSB clustered damage contributes extra DSBs converted from DNA misrepair via pathways for base excision repair and nucleotide excision repair. This study aimed to quantify the relative biological effectiveness (RBE) when DSB induction and conversion from non-DSB clustered damage misrepair were used as biological endpoints. The results showed that both linear energy transfer (LET) and indirect action had a strong impact on the yields for DSB induction and conversion. RBE values for DSB induction and maximum DSB conversion of helium ions (LET = 120 keV/μm) to (60)Co gamma rays were 3.0 and 3.2, respectively. These RBE values increased to 5.8 and 5.6 in the absence of interference of indirect action initiated by addition of 2-M dimethylsulfoxide. DSB conversion was ∼1-4% of the total non-DSB damage due to gamma rays, which was lower than the 10% estimate by experimental measurement. Five to twenty percent of total non-DSB damage due to helium ions was converted into DSBs. Hence, it may be possible to increase the yields of DSBs in cancerous cells through DNA repair pathways, ultimately enhancing cell killing.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4497398 | PMC |
| http://dx.doi.org/10.1093/jrr/rrv025 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
High-throughput DNA repair monitoring in Saccharomyces cerevisiae suggests SSB- and DSB-induced chromatin reconfiguration.
Sci Rep
September 2025
Faculty of Biomedical Engineering, Technion - Israel Institute of Technology, Haifa, 3200003, Israel.
Unlabelled: DNA repair is critical for cellular function and genomic stability across organisms. Yeast mating-type switching serves as an established model for studying DNA break repair and chromosome dynamics. However, real-time tracking of mating-type switching in live cells remains challenging due to resolution limitations of existing techniques.
View Article and Find Full Text PDFThe Mre11 nuclease is part of the highly conserved MRX complex involved in the repair of DNA double-strand breaks (DSBs). During meiosis in budding yeast, MRX is also required for the programmed induction of DSBs by Spo11, thereby initiating homologous recombination to promote accurate chromosome segregation. Recruitment of Mre11 to meiotic DSB sites depends on Rec114-Mei4 and Mer2 (RMM), which are thought to organize the meiotic DSB machinery by a mechanism involving biomolecular condensation.
View Article and Find Full Text PDFTumor irradiation induced immunogenic response: the impact of DNA damage induction and misrepair.
Radiat Oncol
August 2025
Department of Stomatology, Shenzhen University General Hospital, Shenzhen University, Shenzhen, 518055, China.
Focal tumor irradiation, a cornerstone of cancer therapy, has been increasingly recognized for its capacity to provoke systemic immunogenic responses that extend beyond localized tumor control. Recent advances highlight DNA damage, especially DNA double-strand breaks (DSBs), as a central mediator linking radiotherapy to anti-tumor immune activation. Importantly, DNA misrepair, prevalent in cancer cells with deficient or dysregulated repair machinery, serves as a double-edged sword: while fostering tumor adaptation and genomic instability, it also fuels immune recognition through the accumulation of neoantigens, extracellular DNA release, immunogenic cell death, and the modulation of immune-related cytokines and chemokines.
View Article and Find Full Text PDFChanges in brain connectivity and neurovascular dynamics during dexmedetomidine-induced loss of consciousness.
Commun Biol
August 2025
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
Understanding the neurophysiological changes underlying conscious-unconscious transitions is a key goal in neuroscience. Using magnetic resonance neuroimaging, we investigate the network connectivity and neurovascular changes occurring as the human brain transitions from wakefulness to dexmedetomidine-induced hypnosis, and recovery. Hypnosis led to widespread decreases in functional connectivity strength and increased structure-function coupling, indicating functional patterns more constrained by the underlying anatomical connectivity.
View Article and Find Full Text PDFExposure of human lymphocytes to sweeping-frequency ELF MF.
Int J Radiat Biol
August 2025
Department of Radiobiology, Cancer Research Institute, Biomedical Research Center, Slovak Academy of Sciences, Bratislava, Slovakia.
Purpose: Whereas most of the research on possible bioeffects of extremely low frequency magnetic fields (ELF MF) on blood cells has been performed at 50/60 Hz regardless of background fields, here, we exposed human lymphocytes to sweeping-frequency ELF MF in a different range, defined by the DC background field of our incubator and the corresponding ion-cyclotron frequencies.
Materials And Methods: Umbilical cord blood lymphocytes (UCBL) were isolated and exposed for 48 h to an ELF MF (sinusoidal, frequency sweeping 3-26 Hz) with 6 different amplitudes between 6 µT and 24 µT, utilizing an oblong coil. DNA double-strand breaks (DSB) were assessed by enumeration of γH2AX, 53BP1 and γH2AX/53BP1 co-localized DNA repair foci.