Health Phys.Abstracts，Volume 119,Number 1

“LIVINGINCONTAMINATEDAREAS”—CONSIDERATIONOFDIFFERENTPERSPECTIVES

Michael Abend1, Anne Nisbet1, Florian Gering1, Viktor Averin1, Kasper Andersson2, Thierry Schneider1, Carmel Mothersill1, Hajo Zeeb1, Peter Scholz-Kreisel1, Shunichi Yamashita1, Christina Pölz-Viol1, Matthias Port1

(1.Bundeswehr Institute of Radiobiology, Neuherberg str.11, 80937 Munich;2.Technical University of Denmark, DTU Environment, Radioecology and Tracer Studies Section, Frederiksborgvej 399, DK-4000 Roskilde, Denmark)

Abstract:Following large-scale nuclear power plant accidents such as those that occurred at Chernobyl(Ukraine)in 1986 and Fukushima Daiichi(Japan)in 2011, large populations are living in areas containing residual amounts of radioactivity.As a key session of the ConRad conference, experts were invited from different disciplines to provide state-of-the-art information on the topic of “living in contaminated areas.” These experts provided their different perspectives on a range of topics including radiation protection principles and dose criteria, environmental measurements and dose estimation, maintaining decent living and working conditions, evidence of health risks, and social impact and risk communication.A short summary of these different perspectives is provided in this paper.

Keywords: Chernobyl; contamination; decontamination; Fukushima

Health Phys.119(1):2-11; 2020

TOCOLPROPHYLAXISFORTOTAL-BODYIRRADIATION:APROTEOMICANALYSISINMURINEMODEL

Elliot Rosen1, Oluseyi O.Fatanmi2,3, Stephen Y.Wise2,3, V.Ashutosh Rao1, Vijay K.Singh2,3

(1.Division of Biotechnology Research and Review III, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S.Food and Drug Administration, Silver Spring, MD;2.Division of Radioprotectants, Department of Pharmacology and Molecular Therapeutics, F.Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD;3.Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD)

Abstract:The aim of this study was to analyze the changes in mouse jejunum protein expression in response to prophylactic administration of two promising tocols, γ-tocotrienol(GT3)and α-tocopherol succinate(TS), as radiation countermeasures before irradiation to elucidate the molecular mechanism(s)of their radioprotective efficacy.Mice were administered GT3 or TS(200 mg kg-1)subcutaneously 24 h prior to exposure to 11 Gy60Co γ-radiation, a supralethal dose for mice.Jejunum was harvested 24 h post-irradiation.Results of the two-dimensional differential in-gel electrophoresis(2D-DIGE), coupled with mass spectrometry, and advanced bioinformatics tools suggest that the tocols have a corresponding impact on expression of 13 proteins as identified by mass spectrometry.Ingenuity Pathway Analysis(IPA)reveals a network of associated proteins involved in inflammatory response, organismal injury and abnormalities, and cellular development.Relevant signaling pathways including actin cytoskeleton signaling, RhoA signaling, and Rho family GTPase were identified.This study reveals the major proteins, pathways, and networks involved in preventing the radiation-induced injury in gut that may be contributing to enhanced survival.

Keywords:60Co; gamma radiation; mice; radiation protection

Health Phys.119(1):12-20; 2020

MSC-DERIVEDEXTRACELLULARVESICLES:NEWEMERGENCYTREATMENTTOLIMITTHEDEVELOPMENTOFRADIATION-INDUCEDHEMATOPOIETICSYNDROME?

Sophie Cavallero, Diane Riccobono, Michel Drouet, Sabine François1

(1.DEBR/Rad Unit/Biomedical Research Institute of the Armed Forces, 1 place du général Valérie André, 91223 Brétigny sur orge, France)

Abstract:Nuclear accidents or acts of terrorism involving radioactive sources might lead to mass casualties irradiation.The hematopoietic system is one of the most critical and radiation-sensitive tissues because the limited life span of blood cells requires the continuous division of hematopoietic stem cells(HSCs)into the bone marrow.The radiation-induced hematopoietic syndrome, RI-HS, is an impairment of the hematopoiesis that will result in pancytopenia of various degrees.In fact, treatment with granulocyte-colony stimulating factor(G-CSF)is considered as a valuable adjunct to treatment controls in some irradiated patients.Nevertheless, these overexposed patients with bone marrow suppression have minimal medullary territories that do not allow complete recovery of hematopoiesis but lead to significant immunoreactivity following allogeneic hematopoietic stem cell transplantation(HSCT).The high morbidity and mortality of these overexposed patients is a reminder of the lack of effective treatment for hematopoietic syndrome.During the last 20 y, a therapeutic approach for mesenchymal stem cells(MSC)has been proposed for the management of accidentally irradiated victims.Many preclinical animal studies have shown that MSC, mainly by their secretory activity, in particular extracellular vesicles(EVs), contribute to the control of inflammation and promote regeneration of tissues by accelerating angiogenesis and re-epithelialization processes.Therefore, we investigated the potential effect of EVs on the reduction of early bone marrow ionization toxicity, early anti-apoptotic therapy, and vascular protection in the RI-HS model.The main purpose is to propose an innovative treatment of non-patient-specific RI-HS emergency treatment in order to limit allogeneic HSC.

Keywords: accidents, nuclear; accidents, power reactor; emergencies radiological; radiation damage

Health Phys.119(1):21-36; 2020

GENEEXPRESSIONANDCELLULARMARKERSOFOCCUPATIONALRADIATIONEXPOSUREINCHERNOBYLSHELTERCONSTRUCTIONWORKERS

Dimitry Bazyka, Iryna Ilienko, Natalya Golyarnik, Oleg Belyaev, Olena Lyaskivska1

(1.National Research Center for Radiation Medicine, Ukraine)

Abstract:Low-dose radiation effects were studied in Ukrainian personnel of the Chernobyl exclusion zone.The aim of this study was to determine the influence of borderline exposure to annual professional limits and age on expression of molecular markers.Study groups included 300 radiation workers performing construction work on the New Safe Confinement(Arch)upon the Chernobyl “Shelter” ternal dose, 26.1 ± 18.1 mSv; age, 43.1 ± 10.3 y overall and 48.7 ± 5.9 y for 69 control persons〗.Methods included gene expression using RT-PCR, flow cytometry of lymphocyte antigens, gamma-H2AX, Cyclin D1 expression, and relative telomere length using flow-FISH.A statistically significant upregulation ofVEGFABAX,DDB2,NFKB1 was shown at doses below 35 mSv.In workers aged under 40 y with doses higher than 35 mSv, an upregulation of 16 genes was revealed—VEGFA,TERF2,TERF1,BIRC5,BAX,TP53,DDB2,CDKN1B,CDKN2A,NFKB2,MAPK14,TGFBR1,MKNK2,CDKN1A,NFKB1,TP53I3; and four genes were downregulated—MADD,FASL,CSF2, andTERT.In workers older than 40 y, 8 genes were upregulated and 12 were downregulated.All groups showed an increased and dose-dependent gamma-H2AX expression.Downregulation ofCCND1 genes in older groups was accompanied by lower numbers of Cyclin D1 protein expression and lower CD3+and CD4+cell counts.Upregulation ofCSF2 in those over 40 y old positively correlated with B-cell and NK-cell counts.A non-linear type of gene expression response was demonstrated: in doses over 35 mSv for those over 40 y, the increased expression of gamma-H2AX is associated with upregulation of cell survival positive regulators—BIRC5,BRCA1,DDB2,CCND1,TERTgenes, and longer telomeres; the younger age group was characterized byTERF1andTERF2 upregulation and telomere shortening.

Keywords: biomarker; Chernobyl; exposure, occupational; nuclear workers

Health Phys.119(1):37-43; 2020

CTIRRADIATION-INDUCEDCHANGESOFGENEEXPRESSIONWITHINPERIPHERALBLOODCELLS

Hanns Leonhard Kaatsch1, Matthäus Majewski1, Gerrit Schrock1, Richard Obermair1, Jillyen Seidel1, Kai Nestler2, Michael Abend1, Stephan Waldeck2, Matthias Port1, Reinhard Ullmann1, Benjamin Valentin Becker2

(1.Bundeswehr Institute of Radiobiology affiliated to the University of Ulm, Neuherbergstrasse 11, 80937, Munich, Germany;2.Bundeswehr Central Hospital Koblenz, Department of Radiology, Rübenacher Straße 170, 56072 Koblenz, Germany)

Abstract:Computed tomography(CT)is a crucial element of medical imaging diagnostics.The widespread application of this technology has made CT one of the major contributors to medical radiation burden, despite the fact that doses per individual CT scan steadily decrease due to the advancement of technology.Epidemiological risk assessment of CT exposure is hampered by the fact that moderate adverse effects triggered by low doses of CT exposure are likely masked by statistical fluctuations.In light of these limitations, there is need of further insights into the biological processes induced by CT scans to complement the existing knowledge base of risk assessment.This prompted us to investigate the early transcriptomic response of ex vivo irradiated peripheral blood of three healthy individuals.Samples were irradiated employing a modern dual-source-CT-scanner with a tube voltage of 150 kV, resulting in an estimated effective dose of 9.6 mSv.RNA was isolated 1 h and 6 h after exposure, respectively, and subsequently analyzed by RNA deep sequencing.Differential gene expression analysis revealed shared upregulation ofAEN,FDXR, andDDB2 6 h after exposure in all three probands.All three genes have previously been discussed as radiation responsive genes and have already been implicated in DNA damage response and cell cycle control after DNA damage.In summary, we substantiated the usefulness ofAEN,FDXR, andDDB2 as RNA markers of low dose irradiation.Moreover, the upregulation of genes associated with DNA damage reminds one of the genotoxic nature of CT diagnostics even with the low doses currently applied.

Keywords: computed tomography; genetic effects; radiation, low-dose; X-ray imaging

Health Phys.119(1):44-51; 2020

AUTOMATEDDICENTRICABERRATIONSCORINGFORTRIAGEDOSEASSESSMENT:60CoGAMMARAYDOSE-RESPONSEATDIFFERENTDOSERATES

Uma Subramanian1, Brett O’Brien1, Maureen McNamara1, Lyudmila Romanyukha1, David L.Bolduc1, Cara Olsen2, William F.Blakely1

(1.Scientific Research Department, Armed Forces Radiobiology Research Institute(AFRRI), Uniformed Services University of the Health Sciences(USUHS), Bethesda, MD 20889-5648;2.Preventive Medicine and Biostatistics Department(PMB), Uniformed Services University of the Health Sciences(USUHS), Bethesda, MD 20814-4799)

Abstract:The objective of this study was to establish radiation dose-response calibration curves using automated dicentric scoring to support rapid and accurate cytogenetic triage dose-assessment.Blood was drawn from healthy human volunteers and exposed to60Co gamma rays at several dose rates(i.e., 1.0, 0.6, and 0.1 Gy min-1).After radiation, the blood was placed for 2 h in a 37 °C incubator for repair.Blood was then cultured in complete media to which a mitogen(i.e., phytoghemagglutinin, concentration 4%)was added for 48 h.Colcemid was added to the culture at a final concentration of 0.2 μg mL-1after 24 h for the purpose of arresting first-division metaphase mitotics.Cells were harvested at the end of 48 h.Samples were processed using an automated metaphase harvester and automated microscope metaphase finder equipped with a suite of software including a specialized automated dicentric scoring application.The data obtained were used to create dose-response tables of dicentric yields.The null hypothesis that the data is Poisson-distributed could not be rejected at the significance level of α = 0.05 using results from a Shiny R Studio application(goodness-of-fit Poisson).Calibration curves based on linear-quadratic fits for60Co gamma rays at the three different dose rates were generated using these data.The calibration curves were used to detect blind test cases.In conclusion, using the automated harvester and automated microscope metaphase finder with associated automated dicentric scoring software demonstrates high-throughput with suitable accuracy for triage radiation dose assessment.

Keywords:60Co; cytogenetics; dose assessment; dosimetry

Health Phys.119(1):52-58; 2020

BRINGINGRADIATIONEXPOSURESANDASSOCIATEDHEALTHRISKSINTO

PERSPECTIVE—DEVELOPMENTOFANAPP

Michael Abend, Daniela Stricklin, Nicole Flaig, Christophe Badie, Michel Drouet, Crawford Foster, Marek K.Janiak, Tjerk Kuipers, Florigio Lista, Ewa M.Nowosielska, Diane Riccobono, Stefania de Sanctis, Valeria Franchini, Ales Tichy, Matthias Port1

(1.Bundeswehr Institute of Radiobiology, Munich, Germany)

Abstract:The NATO HFM 291 research task group(RTG)on “Ionizing Radiation Bioeffects and Countermeasures” represents a group of scientists from military and civilian academic and scientific institutions primarily working in the field of radiobiology.Among other tasks, the RTG intends to extend their work on risk estimation and communication to bridge the gap in appropriate judgment of health risks given a certain radiation exposure.The group has no explicit psychological background but an expertise in radiobiology and risk assessment.The group believes that, as one of the essential first steps in risk communication, it is required to put radiation risk into perspective.Radiation risk requires a weight in comparison to already-known risks.What we envision is toCompareRadiation exposure-associated healthRisks(CRRis App)with daily life health risks caused by other common exposures such as cigarette smoking, driving a car, etc.Within this paper, we provide(1)an overview of health risks after radiation exposure,(2)an explanation of the task and concept of an envisioned CRRis App,(3)an overview of existing software tools related to this issue,(4)a summary of inputs and discussions with experts in the field of radiation protection and risk communication during the ConRad conference, and finally,(5)identification of the next steps in the development of the App.

Keywords: acute radiation syndrome; education; health effects; risk communication

Health Phys.119(1):59-63; 2020

ANEWSMARTPHONEAPPLICATIONTOPREDICTHEMATOLOGICACUTERADIATIONSYNDROMEBASEDONBLOODCELLCOUNTCHANGES—THEH-MODULEAPP

Matthäus Majewski1, Marco Rozgic2, Patrick Ostheim1, Matthias Port1, Michael Abend1

(1.Bundeswehr Institute of Radiobiology, Munich, Germany.2.Helmut Schmidt University, Hamburg, Germany)

Abstract:Treatment regimens for acute radiation syndrome have been improved over the past years.The application of appropriate therapy relies on rapid and high-throughput tests ideally conducted in the first 3 d after a radiation exposure event.We have examined the utility of blood cell counts(BCCs)3 d post irradiation to predict clinical outcome for hematologic acute radiation syndrome(HARS).The BCCs and HARS severity information originated from data available in the System-for-Evaluation-and-Archiving-of-Radiation Accidents-based-on-Case-Histories(SEARCH).We found an almost complete discrimination of unexposed(HARS score H0)vs.irradiated individuals during model development and validation(negative predictive value >94%)when using BCC data for all 3 d.We also found that BCC data increased the correct prediction of exposed individuals from day 1 to day 3.We developed spreadsheets to calculate the likelihood of correct diagnoses of the worried-well, requirement of hospitalization(HARS 2-4), or development of severe hematopoietic syndrome(HARS 3-4).In two table-top exercises, we found the spreadsheets were confusing and cumbersome, so we converted the spreadsheets into a smartphone application, named the H-module App, designed for ease of use, wider dissemination, and accommodation of co-morbidities in the HARS severity prediction algorithm.

Keywords: accidents, nuclear; blood; health effects; radiation effects

Health Phys.119(1):64-71; 2020

SCIENTIFICANDLOGISTICALCONSIDERATIONSWHENSCREENINGFORRADIATIONRISKSBYUSINGBIODOSIMETRYBASEDONBIOLOGICALEFFECTSOFRADIATIONRATHERTHANDOSE:THENEEDFORPRIORMEASUREMENTSOFHOMOGENEITYANDDISTRIBUTIONOFDOSE

Harold M.Swartz1,2, Ann Barry Flood1, Vijay K.Singh3,4, Steven G.Swarts5

(1.Department of Radiology, Geisel School of Medicine at Dartmouth College, Hanover, NH;2.Department of Medicine/Radiation Oncology, Geisel School of Medicine at Dartmouth College, Hanover, NH;3.Department of Pharmacology & Molecular Therapeutics, F.Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD;4.Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD;5.Department of Radiation Oncology, University of Florida, Gainesville, FL)

Abstract:An effective medical response to a large-scale radiation event requires prompt and effective initial triage so that appropriate care can be provided to individuals with significant risk for severe acute radiation injury.Arguably, it would be advantageous to use injury rather than radiation dose for the initial assessment; i.e., use bioassays of biological damage.Such assays would be based on changes in intrinsic biological response elements; e.g., up-or down-regulation of genes, proteins, metabolites, blood cell counts, chromosomal aberrations, micronuclei, micro-RNA, cytokines, or transcriptomes.Using a framework to evaluate the feasibility of biodosimetry for triaging up to a million people in less than a week following a major radiation event, Part 1 analyzes the logistical feasibility and clinical needs for ensuring that biomarkers of organ-specific injury could be effectively used in this context.We conclude that the decision to use biomarkers of organ-specific injury would greatly benefit by first having independent knowledge of whether the person’s exposure was heterogeneous and, if so, what was the dose distribution(to determine which organs were exposed to high doses).In Part 2, we describe how these two essential needs for prior information(heterogeneity and dose distribution)could be obtained by using in vivo nail dosimetry.This novel physical biodosimetry method can also meet the needs for initial triage, providing non-invasive, point-of-care measurements made by non-experts with immediate dose estimates for four separate anatomical sites.Additionally, it uniquely provides immediate information as to whether the exposure was homogeneous and, if not, it can estimate the dose distribution.We conclude that combining the capability of methods such as in vivo EPR nail dosimetry with bioassays to predict organ-specific damage would allow effective use of medical resources to save lives.

Keywords: bioassay; dosimetry; personnel; emergencies; radiological; emergency planning

Health Phys.119(1):72-82; 2020

RADIATIONEXPOSUREBIOMARKERSINTHEPRACTICEOFMEDICALRADIOLOGY:COOPERATIVERESEARCHANDTHEROLEOFTHEINTERNATIONALATOMICENERGYAGENCY(IAEA)BIODOSIMETRY/RADIOBIOLOGYLABORATORY

Volodymyr A.Vinnikov1, Oleg Belyakov2

(1.Grigoriev Institute for Medical Radiology, Ukranian National Academy of Medical Sciences, Pushkinskaya 82, Kharkiv 61024 Ukraine;2.International Atomic Energy Agency, Vienna International Centre, P.O.Box 100, Vienna A-1400, Austria)

Abstract:The strategy toward personalized medicine in radiation oncology, nuclear medicine, and diagnostic and interventional radiology demands a specific set of assays for individualized estimation of radiation load for safety concerns and prognosis of normal tissue reactions caused by ionizing radiation.Apparently, it seems reasonable to use validated radiation dosimetric biomarkers for these purposes.However, a number of gaps in knowledge and methodological limitations still have to be resolved until dosimetric biomarkers will start to play a valuable role in clinical practice beyond radiation protection and radiation medicine.An extensive international multicenter research is necessary to improve the methodology of clinical applications of biodosimetry.That became a rationale for launching the IAEA Coordinated Research Project E35010 MEDBIODOSE: “Applications of Biological Dosimetry Methods in Radiation Oncology, Nuclear Medicine, and Diagnostic and Interventional Radiology.” At the 2ndCoordination Meeting on MEDBIODOSE(18-22 February 2019, Recife, Brazil), participants reported progress in the usage of biological dosimetry for genotoxicity assessment and/or individualization of radiotherapy treatment plans.Another avenue of research was the prognosis of normal tissue toxicity and cancer risk prediction using biomarkers’ yield measured in vivo or after ex vivo irradiation of patients’ cells.Other important areas are mechanisms of cytogenetic radiation response, validation of new radiation biomarkers, development of innovative techniques, automated and high-throughput assays for biodosimetry, and the overall improvement of biodosimetry service.An important aspect of clinical application of biodosimetry is standardization of techniques and unification of approaches to data interpretation.The new IAEA Biodosimetry/Radiobiology Laboratory, which is being established, will provide support for this activity.The declared lab’s mission includes, among other tasks, a harmonization of the biodosimetry applications with relevant international standards, guidelines on good laboratory practice, and the IAEA EPR—Biodosimetry manual.

Keywords: biological indicators; dosimetry; International Atomic Energy Agency; medical radiation

Health Phys.119(1):83-94; 2020

DETECTIONOFEMBEDDEDLOW-LEVELRADIOACTIVESHRAPNELAFTERTHE

EXPLOSIONOFARADIOLOGICALDISPERSALDEVICEINRADIOLOGICAL

EMERGENCYIMAGING

Matthäus Majewski1, Kai Nestler2, Daniel A.Veit2, Birte Diekmeyer3, Stephan Waldeck2, Matthias Port1, Benjamin V.Becker2

(1.Bundeswehr Institute of Radiobiology affiliated to Ulm University, Genomics I, Neuherbergstrasse 11, 80804, Munich, Germany;2.Department for Radiology and Neuroradiology, Bundeswehr Central Hospital, Rübenacherstrasse 170, 56072, Koblenz, Germany;3.Department for Nuclear Medicine, Bundeswehr Central Hospital, Rübenacherstrasse 170, 56072, Koblenz, Germany)

Abstract:Concern about the threat of a terrorist attack with a Radiological Dispersal Device has increased considerably over the last few years, and this comes along with an immense challenge, especially regarding medical treatment of combined injuries with incorporated radioactive fragments.In such scenarios, the identification and surgical exploration of radioactive fragments is a major issue to prevent further radiation-induced effects like wound healing disorders, onset of acute radiation syndrome, and as a late-effect cancer.However, in a usual emergency setting, it is unclear how this task can be achieved.Within this study, we evaluated the feasibility of different radiological methods to identify and locate an incorporated radioactive fragment.We placed two different137Cs sources and several non-radioactive fragments representing sham control samples within a human spine phantom.Standard emergency imaging procedures were performed, including plane radiography and different CT scans(64 row, 384 row dual energy, 320 row without iterative metal artifact reduction), respectively.Eight radiologists were blinded toward the results and asked to identify the radioactive fragments within the provided images.For both sources, correct identification was rather low(15.63%).Furthermore, none of the questioned radiologists(N= 0)stated that they were able to identify the radioactive shrapnel distinctly.Positive predictive value was accordingly low(15.63%).Most participants recommended a scintigraphy-based technique for identification(26.67%)rather than radiographic procedures(6.67%).Identification and location of incorporated small radioactive fragments with low energies by standard radiological procedures prior to surgical exploration is not promising.Nevertheless, procedures that can achieve this aim are needed direly in the case of a terrorist attack with a radiological dispersal device and should be available in an emergency department.

Keywords:137Cs; computed tomography; diagnostic radiology; emergencies, radiological

Health Phys.119(1):95-100; 2020

EFFECTOFDIFFERENTANTIOXIDANTSONX-RAYINDUCEDDNADOUBLE-STRANDBREAKSUSINGγ-H2AXINHUMANBLOODLYMPHOCYTES

Nicoleta Simona Bicheru1, Cerasela Haidoiu1, Octavian Călborean1,2, Adrian Popa1, Ioana Porosnicu3, Radu Hertzog1

(1.Military Medical Research Center, Bucharest, Romania;2.Faculty of Biology, University of Bucharest, Bucharest, Romania;3.National Institute for Laser Plasma and Radiation Physics, Bucharest, Romania)

Abstract:Ionizing radiation exposure produces direct or indirect biological effects on genomic DNA.The latter are ionizing radiation mediated by induction of free radicals and oxygen species(ROS).The study was conducted to evaluate the dose-effect/time-effect of antioxidant treatments in reducing the induction of double-strand breaks in human blood lymphocytes.Human peripheral blood samples of 2 mL each from healthy donors were irradiated with 10 mGy after pre-incubation with different antioxidants(β-carotene, vitamin E, vitamin C, N-acetyl L-cysteine).In order to assess their efficiency as prophylactic therapy for irradiation, various concentrations and combinations of antioxidants, as well as different incubation times, have been evaluated.To assess double-strand breaks induced by ionizing radiation, the phosphorylated histone γ-H2AX has been used.A significant reduction(p< 0.001)in double-strand breaks studied with a γ-H2AX assay was observed with N-acetyl L-cysteine with a 1-h incubation time, followed by vitamin C, vitamin E, and β-carotene.The use of antioxidants, especially N-acetyl L-cysteine before irradiation, significantly decreased the occurrence of double-strand breaks, demonstrating the potential radiological protection for exposure to ionizing radiation.

Keywords: DNA; health effects; radiation damage; radiation, ionizing

Health Phys.119(1):101-108; 2020

IONIZINGRADIATIONALTERSTHETRANSITION/TRANSVERSIONRATIOINTHEEXOMEOFHUMANGINGIVAFIBROBLASTS

Neetika Nath1,2, Lisa Hagenau1, Stefan Weiss1, Ana Tzvetkova1,2, Lars R.Jensen1, Lars Kaderali2, Matthias Port3, Harry Scherthan3, Andreas W.Kuss1

(1.Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany；2.Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Germany；3.Bundeswehr Institute for Radiobiology, University of Ulm, München, Germany)

Abstract:Little is known about the mutational impact of ionizing radiation(IR)exposure on a genome-wide level in mammalian tissues.Recent advancements in sequencing technology have provided powerful tools to perform exome-wide analyses of genetic variation.This also opened up new avenues for studying and characterizing global genomic IR-induced effects.However, genotypes generated by next generation sequencing(NGS)studies can contain errors, which may significantly impact the power to detect signals in common and rare variant analyses.These genotyping errors are not explicitly detected by the standard Genotype Analysis ToolKit(GATK)and Variant Quality Score Recalibration(VQSR)tool and thus remain a potential source of false-positive variants in whole exome sequencing(WES)datasets.In this context, the transition-transversion ratio(Ti/Tv)is commonly used as an additional quality check.In case of IR experiments, this is problematic when Ti/Tv itself might be influenced by IR treatment.It was the aim of this study to determine a suitable threshold for variant filters for NGS datasets from irradiated cells in order to achieve high data quality using Ti/Tv, while at the same time being able to investigate radiation-specific effects on the Ti/Tv ratio for different radiation doses.By testing a variety of filter settings and comparing the obtained results with publicly available datasets, we observe that a coverage filter setting of depth(DP)3 and genotype quality(GQ)20 is sufficient for high quality single nucleotide variants(SNVs)calling in an analysis combining GATK and VSQR and that Ti/Tv values are a consistent and useful indicator for data quality assessment for all tested NGS platforms.Furthermore, we report a reduction in Ti/Tv in IR-induced mutations in primary human gingiva fibroblasts(HGFs), which points to an elevated proportion of transversions among IR-induced SNVs and thus might imply that mismatch repair(MMR)plays a role in the cellular damage response to IR-induced DNA lesions.

Keywords: analysis, statistical; dose; exposure, radiation; genetic effects

Health Phys.119(1):109-117; 2020

CHARACTERIZATIONOFPRIMARYHUMANDERMALFIBROBLASTSTOENSUREFORINSTANCEEMFEXPOSUREEXPERIMENTSUNDERCOMPARABLECELL

CULTURECONDITION

Valeria Franchini, Thomas Müller, Julian M.Haupt, Patrick Ostheim, Matthaeus Majewski, Florigio Lista, Matthias Port, and Michael Abend1

(1.Bundeswehr Institute of Radiobiology Munich, Neuherbergstr.11, 80937 Munich, Germany)

Abstract:HDFa(human dermal fibroblasts)are used as cellular models for EMF exposure.To ensure reproducible in vitro experiments, comparable proliferation and differentiation cell conditions must exist, and different donors, passage numbers, culture time, and growth media must be considered.In this study, the authors cultured fibroblasts in DMEM or 106 medium.Growth curves, vitality, morphology, and gene expression of genes coding for proliferation(PCNA, CDKN2A, CDKN1A, SFN), differentiation(PDGFRA, TGM2, ACTA2, PDPN, NTN1, MGP, PPP1R14), and SFN target genes(TP63, MMP1, MMP3)were examined in both media and passage numbers 3-4, 5-6 and >6.At passages 3-4, proliferating cells can be observed in both media.While cells cultured in DMEM proliferate over the passages, from passage 5, cells in 106 medium persisted around the seeded number.TGM2 down-regulation over all passages in both media and cells morphology suggest papillary-type fibroblasts.Downregulation of SFN(negative regulator of mitotic translation and cell differentiation)coincided with proliferating fibroblasts over all examined conditions.Downstream SFN target genes in proliferating cells appeared upregulated(TP63)and downregulated(MMP1/MMP3), suggestive for a status characterized by increased stemnesses(upregulated TP63)and wound healing capacity(downregulated MMP1, MMP3).Resting cells(SFN control values)were associated with control values of TP63 and MMP1/MMP3 expression, suggesting a reduced stemness and wound healing capacity.In conclusion, a set of markers related to proliferation(SFN), differentiation(TGM2), stemnesses(TP63), and wound healing(MMP1/MMP3)allow a culture characterization so that cells under two different conditions can be exposed, thus enabling reproducible EMF experiments or experiments with other exposures.

Keywords: biological indicators; electromagnetic fields; health effects; skin dose

Health Phys.119(1):118-127; 2020

MISUSEOFAMEDICALRADIOISOTOPE:125ILABELEDPLAYINGCARDSINGERMANY,ACASESTUDY

Emily Alice Kroeger, Alexander Rupp, Joachim Gregor1

(1.Federal Office for Radiation Protection, Berlin)

Abstract:The security of medical radioactive sources, both open and sealed, is an important consideration for reducing the risk of an intentional or inadvertent additional radiation dose to the public, according to the principle of keeping any additional radiation dose as low as reasonably achievable.The detection and following radiological investigation of the misuse of iodine-125(125I), a medically used radionuclide, in Germany is described in detail with the aim of sharing experience and raising awareness.The misuse of125I shows that the security of125I is not guaranteed completely at the present time.

Keywords:125I; as low as reasonable achievable(ALARA); occupational safety; radiation protection

Health Phys.119(1):128-132; 2020

RESEARCHONTHERADIOTOXICOLOGYOFPLUTONIUMUSINGANIMALS:

CONSIDERATIONOFTHE3Rs—REPLACE,REDUCE,REFINE

Nina M.Griffiths1, Anne Van der Meeren1, Jaime F.Angulo1, Silvia Vincent-Naulleau2

(1.Laboratoire de RadioToxicologie, CEA, Université Paris-Saclay, Bruyères-le-Chtel, 91297 ARPAJON, France,2.Bureau des Etudes Biomédicales chez l’Animal, CEA/DRF/D3P/BEBA, 92260 FONTENAY-aux-ROSES, France)

Abstract:To characterize the health effects of incorporated plutonium, many experiments have been conducted using different animal models.These range from(1)applied(tissue uptake/retention determination, decorporation therapy efficacy),(2)fundamental(gene expression, cancer induction), and(3)dosimetry models.In recent years, the use of animals for scientific purposes has become a public concern.The application of the 3Rs—Replace(use of alternative methods or animals not considered capable of experiencing pain, suffering, and distress), Reduce(reduction in animal numbers), and Refine(better animal welfare and minimization of suffering, pain and distress)—has increased to address ethical concerns and legislative requirements.The introduction of novel non-animal technologies is also an important factor as complementary options to animal experimentation.In radiotoxicology research, it seems there is a natural tendency toReplacegiven the possibility of data reuse obtained from contamination cases in man and animal studies.The creation of “registries” and “repositories” for nuclear industry workers(civil and military)is now a rich legacy for radiotoxicological measurements.Similarly,Reductionin animal numbers can be achieved by good experimental planning with prior statistical analyses of animal numbers required to obtain robust data.Multiple measurements in the same animal over time(external body counting, excreta collection)with appropriate detection instruments also allowReduction.In terms ofRefinement, this has become “de rigueur” and a necessity given the societal and legal concerns for animal welfare.For research in radiotoxicology, particularly long-term studies, better housing conditions within the constraints of radiation protection issues for research workers are an important concern.These are all pertinent considerations for the 3Rs remit and future research in radiotoxicology.

Keywords: contamination; internal; inhalation; lungs, rodent; plutonium

Health Phys.119(1):133-140; 2020

DIAGNOSTICPERFORMANCEOF68Ga-PSMA-11POSITRON-EMISSION-TOMOGRAPHY/COMPUTED-TOMOGRAPHYINALARGECOHORTOFPATIENTSWITHBIOCHEMICALRECURRENCEOFPROSTATECARCINOMA

Manuela A.Hoffmann1,2,3, Hans-Georg Buchholz4, Helmut J.Wieler5, Jonas Müller-Hübenthal6, Ludwin Trampert7, Ines Richardsen8, Mathias Schreckenberger9

(1.Department of Occupational Health and Safety, Supervisory Center for Radiation Protection, Federal Ministry of Defense, Fontainengraben 150, 53123 Bonn, Germany;2.Clinic of Nuclear Medicine, Johannes Gutenberg-University, Langenbeckstraße 1, 55101 Mainz, Germany;3.Clinic of Nuclear Medicine, Bundeswehr Central Hospital, Rübenacher Straße 170, 56072 Koblenz, Germany;4.Clinic of Nuclear Medicine, Johannes Gutenberg-University, 55101 Mainz, Germany;5.Clinic of Nuclear Medicine, Bundeswehr Central Hospital, 56072 Koblenz, Germany;6.Practice of Radiology and Nuclear Medicine, Praxis im KölnTriangle, Ottoplatz 1, 50679 Köln, Germany;7.Clinic of Nuclear Medicine, Klinikum Mutterhaus der Borromäerinnen, Feldstraße 16, 54290 Trier, Germany;8.Clinic of General, Visceral and Thoracic Surgery, Bundeswehr Central Hospital, 56072 Koblenz, Germany;9.Clinic of Nuclear Medicine, Johannes Gutenberg-University, 55101 Mainz, Germany)

Abstract:Gallium-68(68Ga)prostate-specific-membrane-antigen positron-emission-tomography/computed-tomography is a highly promising method for imaging primary and recurrent prostate cancer.These dual-modality imaging technologies enable whole-body functional and anatomical evaluation in a single session.This study investigated the performance of68Ga-prostate-specific-membrane-antigen-11 positron-emission-tomography/computed-tomography for detecting prostate carcinoma in patients with rising prostate-specific-antigen after primary therapy.Six hundred sixty(660)patients with biochemical recurrence referred for positron-emission-tomography/computed-tomography with68Ga-prostate-specific-membrane-antigen-11 were evaluated retrospectively.Prostate-specific-antigen-stratified cohorts of pathological scan results were analyzed, and relationships between prostate-specific-antigen kinetics and PSMA-positive tumor lesions were correlated.Gallium-68 prostate-specific-membrane-antigen-11 positron-emission-tomography/computed-tomography showed a pathological prostate-specific-membrane-antigen uptake in 76%(500 of 660 patients).Positive scans were positively associated with prostate-specific-antigen(p<0.001).For patients with prostate-specific-antigen <0.2 ng mL-1, the PSMA-positive tumor lesions rate was 41%.Patients with prostate-specific-antigen of 0.2-<0.5 ng mL-1, 0.5-<1.0 ng mL-1, 1.0-<2.0 ng mL-1, and 2.0-<5.0 ng mL-1showed rates of 44.7%, 61.7%, 72.3%, 85.2%, respectively, and for prostate-specific-antigen of ≥5.0 ng mL-1it increased to 94%.Prostate-specific-antigen velocity was also correlated with PSMA-positive tumor lesions(p<0.001).In contrast, no association was found for prostate-specific-antigen doubling time(p=0.74).PSMA-positive tumor lesions were significantly increased in patients with primary intermediate-(Gleason Score7)and high-risk(Gleason Score>7)vs.low-risk prostate cancer(Gleason Score<7)(p<0.001).Our data confirm the high performance of68Ga-prostate-specific-membrane-antigen positron-emission-tomography/computed-tomography for the detection of recurrent prostate cancer.This may alter treatment planning and has been documented in other studies as well.

Keywords: cancer; computed tomography; diagnostic imaging; positron emission tomography

Health Phys.119(1):141-147; 2020

ADDITIONALCTA-SUBTRACTIONTECHNIQUEINDETECTIONOFPULMONARY

EMBOLISM—ABENEFITFORPATIENTSORONLYANINCREASEINDOSE?

Kai Nestler,1,2Benjamin Valentin Becker,1Matthäus Majewski,3Daniel Anton Veit,1Bastian Felix Krull,1Stephan Waldeck1

(1.German Federal Armed Forces Central Hospital Koblenz, Department for Radiology and Neuroradiology, Koblenz, Germany;2.Bundeswehr Institute for Preventive Medicine, Division A, Health and Performance Promotion, Andernach, Germany;3.Bundeswehr Institute for Radiobiology affiliated to Ulm University, Munich, Germany)

Abstract:Latest advantages in computed tomography(CT)come with enhanced diagnostic imaging and also sophisticated dose reduction techniques.However, overall exposure to ionizing radiation of patients in Germany rises slightly, which is mainly based on the growing number of performed CT scans.Furthermore, new possibilities in modern imaging, including 4D scans or perfusion protocols, offer new medical insights but require additional scans.In this study, we reevaluated data sets from patients undergoing CT examinations because of suspected pulmonary embolism and compared doses and diagnostic results of the standard protocol to the additional modern CT subtraction technique.Two groups of single-blinded radiologists were provided with CT data sets from 50 patients.One group(G1)had access to full datasets including CT subtraction with perfusion map.The other group(G2)only evaluated conventional CT angiography.Results were compared to final clinical diagnosis.Dose length product(DLP)of CT angiography was compared to CT subtraction technique, which consists of an additional non-contrast-enhanced scan and perfusion map.Effective dose was calculated using a Monte Carlo simulation-based software tool(Impact Dose).Inter-rater agreement of both groups was strong in G1withκ=0.896 and minimal in G2(κ=0.307).Agreement to final diagnosis was strong in both groups(G1,κ=0.848; G2,κ=0.767).Doses applied using the CT subtraction technique were 34.8% higher than for CT angiography alone(G1DLP337.6 ± 171.3 mGy x cm; G2DLP220.2±192.8 mGy、cm;p<0.001).Calculated effective dose was therefore significantly higher for G1(G14.82±2.20 mSv; G23.04±1.33 mSv;p<0.001).Our results indicate a benefit of the CT subtraction technique for the detection of pulmonary embolisms in clinical routine, accompanied by an increase in the dose administered.Although CT protocols should always be applied carefully to specific clinical indications in order to maximize the potential for dose reduction and keep the administered dose as low as reasonably achievable, one should never lose sight of the diagnostic benefit, especially in vital clinical indications.

Keywords: computed tomography; diagnostic radiology; exposure, radiation; lungs, human

Health Phys.119(1):148-152; 2020

EMISSIONOFULTRAVIOLETRADIATIONFROM220TO280nmBYACOLDPHYSICALPLASMAGENERATINGDEVICE

Karsten Kletschkus1, Nadine Gelbrich1, Martin Burchardt1, Axel Kramer2, Sander Bekeschus3, Matthias B.Stope1

(1.Plasma Oncology Laboratory, Department of Urology, University Medicine Greifswald, Greifswald, Germany;2.Institute of Hygiene and Environmental Medicine, University Medicine Greifswald, Greifswald, Germany;3.ZIK plasmatis, Leibniz Institute for Plasma Science and Technology(INP Greifswald), Greifswald, Germany)

Abstract:The generation of cold physical plasma at atmospheric pressure(cold atmospheric plasma: CAP)generates different reactive molecular species as well as radiation in the ultraviolet(UV)range.The therapy of tumor diseases has proven to be a new promising area of application for CAP treatment.With regard to the routine use of CAP in cancer therapy, however, application safety must be ensured both for the patient and for the operator.In this study, the intensity of UVC radiation of the CAP device MiniJet-R(HF Technik, Aachen, Germany)was measured in the range from 220 to 280 nm depending on various device-specific parameters.Depending on the distance to the CAP flame, the UVC intensity reaches values up to 124.5±11 mW m-2.It should be noted here that the UVC radiation generated by the CAP is emitted in all orientations in the room but is also shielded by the geometry of the handpiece of the CAP device.The device-specific settings for the flow rate of the carrier gas, argon, and the power level at the high-frequency(HF)generator of the CAP device also influence the intensity of the UVC radiation.With regard to the medical use of the CAP device, it can be stated that there is an exposure to UVC radiation, which, depending on the duration of treatment, can also be above the maximum value legally specified in Europe.Shielding components on the CAP device can reduce UVC exposure to the operator as well as adverse side effects to the patient.

Keywords: emissions, atmospheric; medical radiation; radiation, non-ionizing; ultraviolet radiation

Health Phys.119(1):153-159; 2020