title: DNA double-strand breaks and micronuclei in human blood lymphocytes after repeated whole body exposures to 7T Magnetic Resonance Imaging.
abstract: To examine the extent of genetic damage, assessed from deoxyribonucleic acid (DNA) double-strand breaks (DSBs) and micronuclei (MN) in peripheral blood mononuclear cells obtained from individuals repeatedly exposed to 7T Magnetic Resonance Imaging (MRI).
  
  
  
  The study protocol was approved by the local ethics committee. Informed consent was obtained from 22 healthy, non-smoking, non-alcoholic male individuals, who had never undergone radio-/chemo-therapy, scintigraphy, and had not undergone X-ray examination one year prior blood withdrawal. Eleven participants were repeatedly exposed to 7T and 3T MRI while working with/around scanners or frequently participating as 7T and lower field MRI research subjects (mean age 34±7years). The other half was never exposed to 7T or lower field MRI and served as controls (mean age 33±9years). The damage in lymphocytes was assessed using anti-γH2AX immunofluorescence staining of DNA DSBs and by quantification of MN. Isolated cells were further exposed in vitro to 7T MRI either alone or in the presence of the DNA damaging drug etoposide, to determine if there is any additional combined effect. The kinetics of DNA damage repair were examined.
  
  
  
  The mean base-level of γH2AX foci/cell and incidence of MN between repeatedly exposed and control group were not significantly different (P=0.618 and P=0.535, respectively). The additional in vitro exposure of cells to 7T MRI had no significant impact on MN frequencies and γH2AX foci at 1, 20 and 72h after exposure.
  
  
  
  Frequently repeated 7T MRI exposure did not result in a detectable increase in genotoxicity indices and alterations of DNA repair kinetics.
authors.affiliation: Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany. Electronic address: Mahsa.Fatahi@ovgu.de.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Fatahi
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Reddig
authors.affiliation: Department of Radiology, University of Texas Health Science Center, San Antonio, USA.
authors.lastname: Vijayalaxmi
authors.affiliation: Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Friebe
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Hartig
authors.affiliation: Department of Pathology, University of Texas Health Science Center San Antonio, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Prihoda
authors.affiliation: Department of Radiology and Nuclear Medicine, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Ricke
authors.affiliation: Medipan GmbH, Dahlewitz, Berlin, Germany; Faculty of Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Senftenberg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Roggenbuck
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Reinhold
authors.affiliation: Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany; German Center for Neurodegenerative Disease, Site Magdeburg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Speck
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics / Q000528:radiation effects*; D004249:DNA Damage; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008214:Lymphocytes / Q000473:pathology / Q000528:radiation effects*; D008279:Magnetic Resonance Imaging / Q000009:adverse effects*; D048629:Micronuclei, Chromosome-Defective / Q000528:radiation effects*; D015162:Micronucleus Tests; D011829:Radiation Dosage; D014916:Whole-Body Irradiation / Q000009:adverse effects* / Q000379:methods
chemical_list: D004247:DNA
keywords: Double strand breaks; Human blood lymphocytes; Micronuclei; Repeated exposure; Ultra-High Field Magnetic Resonance Imaging