Winter
Volume 25, Issue 2, 2014

News and Views

Hiroshima and Nagasaki, Japan

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Table of Contents
From the Editors ......................................................................................................................................... 1
RERF News
Fourth meeting of the Board of Councilors Held at Nagasaki RERF ................................................... 1
Local Liaison Council Meeting Held at Nagasaki RERF ..................................................................... 3
Texas Woman’s University Nursing Doctoral Students Visit Hiroshima RERF,
Meet with Former ABCC Nurses/Staff ............................................................................................. 4
Dr. Susan Lindee, Author/Scholar, Visits Hiroshima Laboratory to Gather Information for
Publication about RERF .................................................................................................................... 5Open House 2014 Held at Hiroshima and Nagasaki RERF .................................................................. 6
Patent Received for Invention “Development and use of an animal model whose internal
cells glow when mutated” ................................................................................................................. 7
Staff News ............................................................................................................................................. 8
Visiting Student Fellows ....................................................................................................................... 8Award Received by RERF Chairman .................................................................................................. 10
Conference and Workshop Reports
Fourth Meeting of the Scientific and Ethics Committee for the Clinical Study of the
F1 Offspring of A-bomb Survivors Held at Hiroshima RERF, by Waka Ohishi ............................. 11
Fifth Epidemiological Training Workshop for Biologists, by Ritsu Sakata ........................................ 12
Meeting of the Conference on Radiation and Health Held in Las Vegas, by Harry Cullings ............. 14International Space Agencies Visit Hiroshima RERF to Further Understanding of
Health Effects from Radiation in Space .......................................................................................... 15
Science Articles
Inverse Associations between Obesity Indicators and Thymic T-cell Production Levels in
Aging Atomic-bomb Survivors, by Kengo Yoshida ........................................................................ 17
A Novel RET Rearrangement (ACBD5/RET) by Pericentric Inversion, inv(10) (p12.1;q11.2),
in Papillary Thyroid Cancer from an Atomic-bomb Survivor Exposed to High-dose
Radiation, by Kiyohiro Hamatani ................................................................................................... 19
Linkage between Dendritic and T-cell Commitments in Human Circulating Hematopoietic
Progenitors, by Seishi Kyoizumi ..................................................................................................... 21
Human Interest Notes
George Takei Visits Hiroshima RERF for Filming of Takei’s Take Involving Technology in Japan ..... 23
Facts and Figures
Neutrons from the Atomic Bombs in Hiroshima and Nagasaki, by Harry M. Cullings ..................... 24
Recent Publications................................................................................................................................... 26
Cover photographs: Texas Woman’s University Ph.D. nursing students/staff in front of RERF (left); see page 4
RERF Chairman Toshiteru Okubo receiving JISHA Distinguished Service Award (right); see page 10

This newsletter is published twice a year by the Radiation Effects Research Foundation (RERF;
formerly the Atomic Bomb Casualty Commission), established in April 1975 as a private,nonprofit Japanese foundation. It is supported by the government of Japan through its Ministryof Health, Labour and Welfare and by the United States through its Department of Energy (DOE),
in part by DOE contract DE-HS0000031 with the National Academy of Sciences. RERF becamea public interest incorporated foundation on April 1, 2012.
RERF conducts research and studies—for peaceful purposes—on medical effects of radiation
and associated diseases in humans, with a view to contributing to maintenance of the health andwelfare of the atomic-bomb survivors and to enhancement of the health of all humankind.
Editor-in-Chief: Harry M. Cullings, Chief, Department of Statistics
Technical Editors: Jeffrey L. Hart, Chief, Setsumi Harachi, Tomoe Matsumoto, Public Relations& Publications Office
Editorial Policy
Contributions to RERF Update receive editorial review only and do not receive scientific peer
review. The opinions expressed herein are those of the authors only and do not necessarily reflect
RERF policies or positions.
Contact: Mailing address: RERF Public Relations & Publications Office, 5-2 Hijiyama Park,
Minami-ku, Hiroshima 732-0815 Japan
Telephone: 81-82-261-3131; Facsimile: 81-82-263-7279
Internet: http://www.rerf.jp/

update 1

From the Editors / RERF News

From the Editors
Greetings from the hilltop on Hijiyama in
Hiroshima and welcome to the Winter 2014 editionof RERF Update. It is early December now and thedays are growing very short. We have had somereal autumn (chilly) weather suddenly in the last
week or so and a sudden loss of foliage from thetrees—it appears that winter may arrive after all.
The seasonal lighting display on Peace Boulevardin the downtown area is even bigger than before,
yet again this year.
With the change in seasons, we have experienced staff changes: the previous technicaleditor of RERF Update, Ms. Tomoe Sugiyama,
was transferred to the administrative staff of the
Epidemiology Dept. Hers was a short but fruitfulstay as editor. Starting with this issue, Mr. Jeffrey
L. Hart, Chief of the Public Relations and Publications Office, and some of his staff will take over thetechnical editor duties.
In this issue of RERF Update we talk about
opening our doors to several important RERF visitors, including Dr. Susan Lindee, the U.S. authorof “Suffering Made Real: American Science andthe Survivors at Hiroshima,” who is researchinga paper on ABCC’s transition to RERF. A groupof doctoral nursing students from Texas Woman’s
University listened to a lecture by Dr. Waka Ohishi,
Chief of the Clinical Studies Dept., and then met
with former ABCC nurses and staff. NASA andother international space agencies held a meeting of the Multilateral Radiation Health Working
Group at RERF for four days in mid-October,based on their desire to understand radiation healtheffects as seen in our research on the health experiences of the survivors of the atomic bombings ofHiroshima and Nagasaki. George Takei, Star Trek
and internet icon, and his crew, as part of a videoseries on technology in Japan, visited his ancestral
home of Hiroshima in early summer and filmed Dr.
Harry M. Cullings explaining GIS technology andits use in more accurately determining
A-bomb survivors’
locations at the timeof bombing. Links
to the four relevant
Takei’s Take videos
appear on our Facebook page (“Radiation Effects Research
Foundation”).
We discuss, inHarry Cullings, PhD
our science articles,
recent research taking place at RERF, as well asreports on meetings and workshops held at RERF
and a major radiation-related scientific meeting in
Las Vegas. Dr. Cullings has provided material in
the “Facts and Figures” article about the issue ofneutrons from the atomic bombings of Hiroshima
and Nagasaki, providing a numerical perspectiveon the impact of neutrons compared with that of
gamma-rays for the radiation doses received bysurvivors, an issue of enduring concern.
We hope that you enjoy this issue of RERF
Update as we approach the end of the year andwinter, as well as the myriad year-end parties, orbonenkai, that accompany this cold but warmly festive season in Japan.

Harry M. Cullings
Editor-in-Chief
Technical Editors
Jeffrey L. Hart
Setsumi Harachi
Tomoe Matsumoto

Fourth Meeting of the Board of Councilors Held at Nagasaki RERF
The fourth meeting of the RERF Board of
Councilors (BOC) was held at the Nagasaki Laboratory over the course of two days, June 19–20,
2014. The meeting was attended by seven of theeight councilors, as well as directors, auditors,
and the Japanese co-chair of the Scientific Advisory Committee. Representatives of the U.S. andJapanese governments and the U.S. National AcadReturn to Table of Contents

emy of Sciences also attended as observers. Executive Councilor Jonathan M. Samet served as themoderator. In their remarks at the beginning of themeeting, the representatives of the U.S. and Japan
governments confirmed their intention to continue
support of RERF. The meeting’s major agenda
items and discussions are summarized below.
The FY2013 activities, settlement of accounts,
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RERF News

List of Participants

Fourth Board of Councilors meeting held at the Nagasaki
Laboratory: Executive Councilor Jonathan Samet (right) andVice Executive Councilor Ohtsura Niwa (left)

and audit results were reported, with the settlementof accounts approved without any modification.
Regarding the FY2014 activity plans, as in the previous year, reports were made on research projects
related to the health of A-bomb survivors and of
their children; research to review individual radiation doses and elucidate radiation’s effects on risk
estimates; projects to release research results to the
public and to collaborate with other scientific organizations; training programs for Japan and overseas
specialists; public information programs; activities
necessary to carry out these projects; as well as
budget estimates for all the activities. An explanation was also given on the schedule of operations
for the Biosample Center, which was established in
April 2013.
Scientific Advisory Committee Co-chair Yoichi
Gondo reported the committee’s recommendations
for the activities of the Departments of Epidemiology, Statistics, and Information Technology, issued
as a result of its 41st meeting held at the Hiroshima
Laboratory March 3–5, 2014. General recommendations were made on research prioritization,
improvement of research quality, future plans forreorganization of research departments and personnel training, and enhancement of the global impact
of RERF and its contributions to society. RERF’s
responses to these recommendations were also discussed at the meeting.
Next, based on the various appointment procedures stipulated in the BOC operational regulations, which were set forth this year, two Councilors and two Scientific Advisors were appointed.
Finally, it was decided to hold next year’s BOC
meeting in Washington, D.C., June 18–19, 2015.
On June 17, an informal gathering will be held
prior to the BOC meeting, as was the case this year.

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Councilors
Dr. Jonathan M. Samet, Professor and Flora L.
Thornton Chair, Department of Preventive
Medicine, Keck School of Medicine; andDirector, Institute for Global Health, Universityof Southern California
Dr. Ohtsura Niwa, Emeritus Professor, Kyoto University
Dr. Hiroo Dohy, Director, Japanese Red Cross
Chugoku-Shikoku Block Blood Center
Dr. Shelley A. Hearne, Visiting Professor, Johns
Hopkins Bloomberg School of Public Health,
Department of Health Policy and Management
Mr. Masaaki Kuniyasu, Former Ambassador
Extraordinary and Plenipotentiary to the
Republic of Portugal
Dr. Yasuhito Sasaki, Director General, ClinicalResearch Center, Shonan Kamakura General
Hospital
Mr. James W. Ziglar, Senior Counsel, Van Ness
Feldman and Senior Fellow and Advisor to theBoard, Migration Policy Institute (Former Sergeant at Arms of the United States Senate)(Not in attendance)
Dr. James D. Cox, Former Head, Department ofRadiation Oncology, The University of Texas
M.D. Anderson Cancer Center
Directors
Dr. Toshiteru Okubo, Chairman/Representative
DirectorDr. Roy E. Shore, Vice Chairman and Executive
Director
Mr. Takanobu Teramoto, Executive Director
Auditors
Mr. Takashi Kohno, Hiroshima General Law/
Accounting Office (Hiroshima CPA Cooperative Office/A&A Tax Accountant Corporation)
Mr. David Williams, Retired Chief Financial Officer, National Academy of Sciences; Certified
Public Accountant
Co-chair of Scientific Advisory Committee
Dr. Yoichi Gondo, Team leader, Mutagenesis andGenomics Team, RIKEN BioResource Center
Representatives of Supporting Agencies
Mr. Takeshi Sakakibara, Director, A-Bomb Survivor Support Office, General Affairs Division,
Health Service Bureau, Ministry of Health,Labour and Welfare (MHLW)
Dr. Shuichiro Hayashi, Deputy Director, General
Affairs Division, Health Service Bureau,
MHLW
Mr. Hiroki Yamamoto, Deputy Director, A-Bomb
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RERF News
Survivor Support Office, General Affairs Division, Health Service Bureau, MHLW
Dr. Patricia R. Worthington, Director, Office of
Health and Safety, Office of Environment,
Health, Safety and Security, DOE
Dr. Isaf Al-Nabulsi, Senior Technical Advisor,
Japan Program Manager, Office of Health and
Safety, Office of Environment, Health, Safety
and Security, DOE
Dr. Kevin D. Crowley, Director, Nuclear and Radiation Studies Board, Division on Earth and Life

Studies, National Research Council, U.S.
National Academy of Sciences
RERF
Dr. Robert L. Ullrich, Associate Chief of Research
Dr. Kazunori Kodama, Chief Scientist
Mr. Eiji Akimoto, Chief of Secretariat
Mr. Douglas C. Solvie, Associate Chief of Secretariat
Mr. Yutaka Ogasawara, Associate Chief of Secretariat

Local Liaison Council Meeting Held at Nagasaki RERF
The 23rd meeting of the Nagasaki Local Liaison Council (NLLC) was held in the third-floor
conference room at Nagasaki RERF on October 15,
2014. Of 21 Council members, 12 (including four
proxies) were in attendance.
Prior to the start of the meeting, Mr. Eiji
Akimoto, RERF Chief of Secretariat, introduced
the new Council members. After greetings by
RERF Chairman Toshiteru Okubo, the proceedings
got underway, with NLLC Chairman Dr. Shigeru
Katamine (President of Nagasaki University) presiding over the meeting.
Dr. Okubo first reported on the present status
of RERF. Vice Chairman and Executive Director
Roy E. Shore then spoke about recent research,and Chief Scientist Kazunori Kodama reported
on progress made at the RERF Biosample Centerin terms of methods related to the preservation
and use of biosamples. Dr. Okubo subsequently

reported on progress in the collaborative study with
the U.S. National Institute of Allergy and Infectious Diseases (NIAID), followed by Executive
Director Takanobu Teramoto explaining RERF’s
public relations activities.
Each of the above reports was followed by aquestion-and-answer session and active debate
among the Council members, including about such
topics as data in RERF’s possession and RERF
research achievements, resulting in the expressionof many valuable opinions.
Dr. Katamine concluded the 23rd NLLC meeting with the following closing remarks: “Theobjectives of this Council are to compile requests
from the local community and have them reflected
in RERF’s operations. I hope that RERF can fully
review and utilize in its future operations the comments and opinions expressed during this meeting.”

Scene of the 23rd Nagasaki Local Liaison Council meeting held at Nagasaki RERF

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RERF Update Volume 25, Issue 2, 2014

RERF News

update 4

Texas Woman’s University Nursing Doctoral Students Visit Hiroshima
RERF, Meet with Former ABCC Nurses/Staff
On October 16, 2014, RERF was visited by
ficult circumstances under which they had labored.
a group of nursing doctoral students from Texas
According to Dr. Cesario about their meeting, “I
Woman’s University, whose nursing doctoral profeel that the Japanese nurses were talking aboutgram is the largest in the United States. The purissues rarely discussed in their day-to-day life.”
pose of the group’s trip to Japan—part of an elecTouring RERF and hearing of the ongoingtive study-abroad course titled “Historical Researchresearch carried out at the institute was reported toin Nursing–Exploring Japan” that is designed to
be another of the highlights of the Texas Woman’s
introduce historical research in the field of nursing,
University trip. Afterward, there was said to be
including methodology, significance, analytic techunanimous agreement among the members regardniques, and application—was to highlight the siging the importance of continuing the scientificnificance of historical nursing research. The Texas
work that takes place at RERF. Because of the varWoman’s University course aimed at illustrating
ied backgrounds and interests of the group memthe process of conducting historical research based
bers, however, each had her own idea regarding
on lessons learned following the Hiroshima andwhat area of research she found most interesting.
Nagasaki A-bombings at the end of World War
Later that evening, the class enjoyed dinner
II and the contribution of those historical eventsand discussion with Dr. Susan Lindee, author ofto the current understanding of radiation therapy,“Suffering Made Real: American Science and theoccupational safety, civil defense, environmental
Survivors at Hiroshima,” who happened to pay acontrols, disaster response, and ethics.
visit to Hiroshima RERF the next day, October 17
Dr. Sandra K. Cesario, Program Coordinator(for related information, please refer directly to
and Professor, College of Nursing, Texas Woman’s
our Facebook page [Radiation Effects Research
University—Houston Campus, led the class comFoundation] or by clicking the Facebook link onprised of one other university staff member and five
the RERF homepage, and to page 5 of this edition
doctoral students to Japan. Dr. Cesario indicatedof Update).
that students, through this course, have the opporThe group’s three-day trip to Hiroshima, as
tunity to evaluate personal worldviews, values, andpart of the eight-day total, made the content of
the professional nursing role in the context of thethe history course “come to life,” according to Dr.
global health community.
Cesario. Dr. Cesario indicated that the historical
After two days in Tokyo, spent speaking toresearch data from the Hiroshima and Nagasaki
Japanese nursing doctoral students, the groupatomic bombings, which make a large contribuvisited Hiroshima. At RERF, after viewing ourtion to scientific understanding of radiation healthintroductory video, the group was taken on a tour
effects and are used around the world today toof the facilities and listened to a lecture delivered
shape policies on occupational, environmental andby Dr. Waka Ohishi, Chief, Departmentof Clinical Studies, who provided an
overview of the history and the conduct
of RERF’s Adult Health Study (AHS)
study since the study’s inception in1958.
After the lecture and lunch, the groupof visitors from Texas met with four
former Japanese ABCC-RERF employees, three of whom had been nurses
attending to the A-bomb survivors, with
their period of employment comprising different periods between 1947 and1989. One of the highlights of the students’ trip was said to be the chance to
speak with the Japanese women, who
had been in Hiroshima or Nagasaki at
Texas Woman’s University students/staff with former ABCC/RERF nurses/
around the time of the bombings. The
staff
students expressed their feelings about(from left, at rear: Deborah Unruh; Terrylene Ingle; Sabrenda T. Littles; Vicki
how inspirational it was listening to the
Brooks; Sandra Cesario; Jen Heathman; Rhonda Kitchen; in front row:
ABCC employees’ stories, given the difSetsuko Fujimoto, Hisae Tanaka, Kiyoko Minato, Merry Y. Uemoto)
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RERF Update Volume 25, Issue 2, 2014

RERF Newsother exposures, perfectly fulfill the objectives of
the course.
On the day before visiting RERF, the group
visited Hiroshima Peace Memorial Park. And, in
Dr. Cesario’s words, “No trip to Hiroshima would
be complete without a trip to the Peace Memorial
Park. The entire complex was breathtaking. We
found the Hall of Remembrance to be the mostmoving.”
We at RERF are pleased to have been able toupdate 5
provide relevant historical information related tonursing and medical care, as well as serve as avenue for a bicultural meeting between U.S. andformer ABCC-RERF nurses and staff. We feel that
RERF is a compelling site for anyone travelingto Hiroshima or Nagasaki as a tourist or student,
and we welcome other university study-abroad
programs to visit and learn about RERF and our
research into the radiation health effects from the1945 atomic bombings of Hiroshima and Nagasaki.

Dr. Susan Lindee, Author/Scholar, Visits Hiroshima Laboratory toGather Information for Publication about RERF
Dr. Susan Lindee, Professor and former Associate Dean for the Social Sciences, School of Arts
and Sciences, University of Pennsylvania and avisiting research scholar at the Graduate Schoolfor International Development and Cooperation(IDEC), Hiroshima University, visited Hiroshima
RERF on October 17, 2014. While here, she met
and spoke with RERF directors and a number of
research scientists as a means of gathering information for a scholarly article on the historical transition from ABCC to RERF, the current status of
RERF, and the organization’s future with respect to
its research on radiation risks.
Dr. Lindee is author of the well-regarded bookabout the early years of ABCC, titled “Suffering
Made Real: American Science and the Survivors
at Hiroshima,” published by University of Chicago
Press in 1994 and reviewed on our Facebook page.

Dr. Susan Lindee (left) and Dr. John Cologne, Senior
Scientist, Statistics Dept., inside RERF beneath a bannercommemorating ABCC-RERF’s 60th anniversary
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She is particularly interested in describing in her
upcoming article about how RERF’s research,which she terms “epidemiology without end,”might be used in many different scenarios for scientific planning of unknown future risks, such as
both technological and natural disasters.
Dr. Lindee’s IDEC appointment is scheduled
for the period October 1—December 26, 2014.
While at IDEC, Dr. Lindee will be teaching a
graduate course on Cold War science—a subject
she teaches in the United States at the Universityof Pennsylvania—in a position to which she wasappointed by the president of Hiroshima University.
At RERF, Dr. Lindee met first with Chairman
Toshiteru Okubo for a conversation about RERF and
the A-bomb survivors, followed by interviews of Dr.
Roy E. Shore, Vice Chairman and Executive Director; Mr. Takanobu Teramoto, Executive Director;
and Dr. Akio Awa, former Chief of Genetics/Associate Chief of Research, who was present in the days
when RERF was changing over from ABCC.
After lunch with some of the staff at a local
sushi restaurant, Dr. Lindee met with Dr. Kazunori
Kodama, Chief Scientist; Dr. Robert L. Ullrich,
Associate Chief of Research; Dr. Harry M.
Cullings, Chief, Statistics Department; and Dr. Eric
J. Grant, Assistant Chief, Epidemiology Department. Dr. Lindee joined Dr. John B. Cologne,
Senior Scientist, Department of Statistics—who,along with Mr. Jeffrey L. Hart, Chief, Public Relations and Publications Office, organized the visit—
for a photo session beneath the banner inside thefacilities commemorating ABCC-RERF’s 60th
anniversary (the organization is now in its 67th
year; see photograph at left) and at the front
entrance outside, next to the pond of Japanese koi.
According to Dr. Lindee, her new project
involves the story of ABCC’s transition to RERF,“partly because that transition led many involved
to articulate why the project was important and
RERF Update Volume 25, Issue 2, 2014

update 6

RERF News
had to be continued.” She wanted to visit RERF to
speak with those directly involved in determining
the direction of RERF’s research efforts, because,in her words, “What I feel I have absolutely nounderstanding of at this stage is the current thinking about the future of RERF—I have seen a few
references, but I need to understand much better
how things look to those involved today.”
ABCC-RERF is a scientific organization dat-

ing back to 1947, with ABCC becoming RERF in
1975. We are fortunate to be able to provide accessto an influential science historian who strives toconvey a detailed view of both the historical ABCC
and the current RERF. The ABCC era was covered
in Dr. Lindee’s historical interpretation of the organization, and we now await the follow-up work thatis to cover the contemporary RERF. We wish Dr.
Lindee great success in her latest endeavor.

Open House 2014 Held at Hiroshima and Nagasaki RERF
The RERF Hiroshima and Nagasaki Laboratories held their 20th and 18th Open House events,
under the theme “Explore and Discover RERF,” onAugust 5–6 and August 8–9, 2014, respectively.
At the event in Hiroshima, a special exhibit
titled “Considering the health effects of low-doseradiation exposure based on atomic-bomb radiation studies” was displayed, in addition to general
exhibits reporting recent achievements from ourresearch, which continues because of the understanding and cooperation of A-bomb survivors andnumerous others. Many children enjoyed ‘handson’ events such as experiments with liquid nitrogenand DNA extraction from broccoli at the sciencecorner, as well as a quiz/stamp rally that they
played while walking around the facilities.
On each of the two days, Dr. Masataka Taga,
Research Scientist, Department of Radiobiology/
Molecular Epidemiology, gave a lecture titled“What is radiation? Basic properties and healtheffects of radiation” involving background information about radiation. Dr. Yoshiaki Kodama,Chief, Department of Genetics, presented a lecture
titled “Radiation exposure and chromosome aberration” concerning radiation-induced chromosomal
damage.
Following the aforementioned lectures, Mr.
Jeffrey L. Hart, Chief, Public Relations and Publications Office and a translator in the Translation
Office, delivered a presentation titled “That’s why
translation is fun! The art of English translating ina scientific environment.” The presentation comprised an explanation of the work of translationfrom Japanese into English, touching on culturaland other differences.
Despite the rainy weather, 889 people visitedthe laboratory over the course of the two days.
Visitors and RERF staff members engaged in active
communication at the event, and families with children in particular were prominent throughout thefacilities.
At Nagasaki RERF, as in Hiroshima, a special
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exhibit titled “Considering the health effects of
low-dose radiation exposure based on atomicbomb radiation studies” was displayed, as weregeneral exhibits introducing methods and results of
RERF’s studies.
For the first time at the Nagasaki Laboratory,
lectures were presented by research scientists:“RERF clinical studies on A-bomb survivors andchildren of A-bomb survivors,” by Dr. Ayumi Hida,
Acting Chief, Department of Clinical Studies; andScene from Open House, Hiroshima: A boy studying cancer cells

Open House, Hiroshima: Dr. Masataka Taga, Research
Scientist, Radiobiology/Molecular Epidemiology Dept.,
speaking to visitors

RERF Update Volume 25, Issue 2, 2014

RERF News

Open House, Nagasaki: Children filing into Nagasaki RERF

“What is radiation? Basic properties and healtheffects of radiation,” by Dr. Taga. Based on discussions with Hiroshima staff members regarding the

update 7
results of a questionnaire survey from last year,
a QR code for cell phones and smartphones was
newly added to this year’s flyer advertising theOpen House event for the purpose of appealing tocollege students and adults.
Fortunately, there was no rain over the two daysof the Nagasaki Open House, despite the hot andhumid weather ahead of an approaching typhoon.
A total of 529 visitors to the laboratory for thetwo days were welcomed by RERF staff members.
The questionnaire survey results showed a slightincrease in proportion of adult visitors (ages 20
to 59). Furthermore, it was notable that the rate of
response to the questionnaire increased to 81.7%,
compared with last year’s 74.1%. The survey information is expected to greatly contribute to the planning and holding of the Open House event next year.

Patent Received for Invention “Development and use of an animalmodel whose internal cells glow when mutated”
Patent #: 5525683“Development and use of an animal model whose
internal cells glow when mutated”
Asao Noda, Assistant Chief, Department of
Genetics
Nori Nakamura, Consultant, Department of
Genetics
Radiation Effects Research Foundation
A patent was granted to Dr. Asao Noda, Assistant Chief, and Dr. Nori Nakamura, Consultant,both of the Department of Genetics, for their invention titled “Development and use of an animalmodel whose internal cells glow when mutated.”
Radiation and environmental mutagens are
known to cause mutations (alterations of a cell’sDNA) in the cells that make up the body. With
the purpose of creating a model mouse that would
allow the measurement of mutation risks forsomatic/germ cells, the aforementioned inventors
succeeded in developing a mouse in which mutatedcells glow green in vivo to allow easy detection of
mutations inside the body, obtaining a patent forthis invention. It is expected that the relevant model
mouse will be utilized for the benefit of society,such as in environmental monitoring and safetyassessment of food, pharmaceuticals, and more.
The relevant June 18, 2014, issue of the Patent
Gazette is available at the Industrial Property Digital Library (IPDL), a free-of-charge database of the
National Center for Industrial Property Information
and Training.

Patent certificate

Image of mutated cells illuminated in tissue
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RERF Update Volume 25, Issue 2, 2014

update 8

RERF News

Staff News
Mieko Kodaira’s term as Chief of the Laboratory of Biochemical Genetics, Department of
Genetics, expired on June 30, 2014. She was reappointed as Adjunct Specialist (research scientist)
effective July 1, in order to continue her research at
the same laboratory.
Fukiko Mitsui joined the Department of Clinical Studies as a research scientist as of October 1,
2014. She introduces herself in the following section.
Fukiko Mitsui, MD, PhD
On October 1, 2014, I assumed the position of
fixed-term research scientist at the Department ofClinical Studies in Hiroshima.
Starting in 2000, after graduating from the Faculty of Medicine, Hiroshima University, I served asa resident at the Hiroshima University Hospital andthe Hiroshima Red Cross Hospital & Atomic-bomb
Survivors Hospital for two years. I subsequently
joined the Department of Internal Medicine I(present-day Department of Gastroenterology andMetabolism), Faculty of Medicine, Hiroshima
University, worked for the JA Hiroshima General
Hospital, and in 2005 entered the Graduate Schoolof Biomedical & Health Sciences, Hiroshima University.
The theme of my doctoral research at the graduate school was: “Study of the therapeutic effectiveness of nucleotide analogues (antiviral drugs)
for hepatitis B.” With the advent of nucleotide
analogues, dramatic progress has been made in
the area of treatment for hepatitis B. Since suchtreatment is ineffective in some cases, however, I

studied the factors affecting antiviral effectiveness.
Upon completion of my doctoral degree basedon this research, I worked at the Hiroshima Red
Cross Hospital & Atomic-bomb Survivors Hospital
until I left the hospital for the birth and care of mychild. In April 2013, I assumed the post of visiting research associate at the RERF Department ofClinical Studies in Hiroshima to engage in healthexamination work.
I was hired as a fixed-term research scientist at
the Department of Clinical Studies in Hiroshima
most recently to also engage in research. I hope tocontribute to the department’s research activities,
while studying the long history of RERF and its
research achievements. Since there are so manythings I need to learn, I would appreciate everyone’s continued support.

Research Scientist Fukiko Mitsui in her office at ClinicalStudies Dept., Hiroshima RERF

Visiting Student Fellows
Kaitlin Kelly-Reif (Training period: June 17–
August 18, 2014)
As a summer fellow of the Japan Society for the
Promotion of Science (JSPS), I studied at RERF
under the guidance of Dr. Harry M. Cullings,
Chief, Department of Statistics. While at RERF,
I conducted a geostatistical estimation of residual
radiation in the area near the hypocenter of theHiroshima atomic bomb as well as the Koi-Takasu
area in the western part of Hiroshima, using historical surveys and spatial hierarchical modelingtechniques.
I grew up in Sacramento, California, where I
developed my interest in health sciences at an early
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age by monitoring air quality at my high school asa volunteer with the American Lung Association.
I attended college at UCLA, where I continued
my studies in environmental science, conservation
biology, and geographical information systems(GIS). After college, I traveled extensively and then
lived in the Republic of Cameroon, in Africa, working for an environmental research group. In 2012, I
moved to Chapel Hill, North Carolina, where I currently live. I am pursuing a Ph.D. in environmental
and occupational epidemiology at the University ofNorth Carolina at Chapel Hill.
Although I am training as an epidemiologist, I
have a strong interest in geospatial statistics and
RERF Update Volume 25, Issue 2, 2014

RERF News

Kaitlin Kelly-Reif during training at RERF, with Dr. Harry
Cullings (left) and Mr. Takanobu Teramoto, Executive Director (right)

environmental modeling. These are important tools
with the potential to improve exposure information for many different types of epidemiologicalstudies. Working with Dr. Cullings has given me
a great introduction to these methods, knowledge
that is sure to enhance my future doctoral research.
Attending meetings in the Epidemiology and Statistics Departments has provided me with valuable
insight into the long-term health consequences of
the atomic bombings. I also have developed a morenuanced understanding of the historical, social, andmethodological challenges that radiation scientists
face in addressing radiation risk.
I have enjoyed my time working at RERF, andalso enjoyed my time exploring Japan’s natural
beauty. I am particularly fond of the Japan Alps andthe Shimanami Kaido bicycle route. I look forward
to returning to Japan in the near future for more
research and travel.
I am grateful to RERF, JSPS, and the National
Science Foundation for making this valuable
opportunity possible. In addition to research support, JSPS provided an excellent language and culture orientation for all its summer fellows. I would
like to thank Dr. Cullings in particular for his assistance and expertise on this project. I would also
like to thank my friends and colleagues at RERF
who have helped me throughout my time here.
Yoshifumi Kondo (Training period: October 1,
2014–January 20, 2015)
I am a visiting research fellow at RERF’s
Department of Radiobiology/Molecular Epidemiology (R/ME). At the same time, I study medicine

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update 9
at Hiroshima University and, as such, have theprivilege of undergoing training at RERF as part of
the university’s medical training program provided
in the latter half of the fourth year of the program.
I learned about RERF’s plan to accept trainees
when Dr. Toshiteru Okubo, RERF Chairman, visited our university to give a lecture, and I decided
to seek the valuable opportunity. I am studying
under Dr. Kengo Yoshida, Research Scientist of thesame R/ME Department, since I am particularlyinterested in biochemistry and hematology among
all the other interesting classes at the university,
among which I am having such difficulties choosing a future career path.
I was born and raised in Hiroshima and havethus known about RERF on Hijiyama since I wasin elementary school. However, I feel that thistraining in particular has been instrumental inteaching me about the history and role of RERF.
I am committed to doing my best to grow during
the training period under the mentorship of the R/
ME members, although I have little experience inor knowledge of work related to lab experiments.
At my university, I retired last year from a
motorsports club, where I had many good friends,
and am now a member of a pop music club. I likemotorsports and enjoy going for a drive to thebeach and the mountains while listening to myfavorite music.
In conclusion, I am grateful for the thoughtfulness of everyone at RERF to make sure that I gaina footing not only in research activities but also inlife at RERF. I ask for your continued support.

Yoshifumi Kondo in his office as student trainee at Radiobiology/Molecular Epidemiology Dept.

RERF Update Volume 25, Issue 2, 2014

update 10

RERF NewsAward Received by RERF Chairman
RERF Chairman Toshiteru Okubo Receives JISHA Distinguished Service AwardRERF Chairman Toshiteru Okubo was recently
honored as the recipient of the 2014 DistinguishedService Award of the Japan Industrial Safety and
Health Association (JISHA). The award ceremony
took place during the general conference of the73rd National Industrial Safety and Health Convention, held at the Hiroshima Prefectural Sports
Center on October 22, 2014.
Starting with his work at Japan’s Universityof Occupational and Environmental Health in his
previous post, Dr. Okubo has endeavored to establish a system of specialization for occupational
physicians, whose role is to protect worker safety
and health, in order to enhance the professionalism
and improve the status of this particular group ofphysicians. He has made significant contributions
for more than 30 years to the development of occupational health and the prevention of workplace
accidents in Japan. Chairman Okubo’s considerable achievements were acknowledged with thepresentation of this year’s JISHA DistinguishedService Award.
To commemorate Dr. Okubo’s prestigious
award, Mr. Takanobu Teramoto, Executive Director, Dr. Kazunori Kodama, Chief Scientist, andMr. Eiji Akimoto, Chief of Secretariat, organizeda gathering at the traditional Japanese restaurant

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Mitaki-So, in Nishi-ku, Hiroshima, on October
24. This festive occasion was attended by RERF
colleagues and distinguished guests, including
President Ginji Endo of the Japan Society of Occupational Health, RERF Councilor Hiroo Dohy, andRERF Auditor Takashi Kohno.

RERF Chairman Toshiteru Okubo backstage, with the JISHA
Distinguished Service AwardRERF Update Volume 25, Issue 2, 2014

Conference and Workshop Reports

update 11

Fourth Meeting of the Scientific and Ethics Committee for the Clinical Studyof the F1 Offspring of A-bomb Survivors Held at Hiroshima RERF
Waka Ohishi, Chief
Department of Clinical Studies, Hiroshima
The fourth meeting of the Scientific and Ethics
Committee for the Clinical Study of the F1 Offspring of A-bomb Survivors was held at the RERF
Hiroshima Laboratory Auditorium on May 15,
2014, in order to deliberate on a report regarding
progress of the Longitudinal Clinical Study of the
F1 Offspring of A-bomb Survivors and draft revisions of the informed consent form and explanatory documents in accordance with the revisionsof the Ethics Guidelines for Human Genome/GeneAnalysis Research.
In the previous health effects study of the children of A-bomb survivors, a mail survey of 24,673
subjects and a clinical health study of 11,951 subjects were conducted between 2000 and 2006 to
determine the relationship between parental radiation exposure and the prevalence of multifactorialdiseases among their children. In that study, we
found no evidence showing an increase of diseaserisks related to parental radiation exposure, either inanalyzing six multifactorial diseases (hypertension,
hypercholesterolemia, diabetes, angina pectoris,
myocardial infarction, and stroke) together or inanalyzing the individual multifactorial diseases
separately. However, continuation of the study wasrecommended because in such prevalence studies
there tends to be a bias related to decision-making
among the participants regarding whether or not
to undergo health examinations. Moreover, at thattime the average age of the subjects, about 49 years,
was still relatively young. In response to this recommendation, on November 24, 2010, the Longitudinal Clinical Study of the F1 Offspring of A-bomb
Survivors was initiated for about 12,000 subjects.
The meeting’s proceedings began with greetings and the introduction of committee members
by RERF Chairman Toshiteru Okubo, which was
followed by greetings from committee Chairman
Tadao Shimao. Dr. Ohishi reported on the progress
made in the Longitudinal Clinical Study of the F1
Offspring of A-bomb Survivors during the three
years since its initiation. Measures have been taken
since the year before last to include people who
remained undecided about undergoing examination and people whose address was unknown. Letters requesting participation were re-sent to those
who had refused to undergo examination, and as
a result, the participation rate including expectedparticipants has improved steadily, increasing from
69.2% in the first year to 76.0% and 76.8% after
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two and three years, respectively. Future plans forthe longitudinal study were also explained: the firstexamination cycle (four years) concluded at theend of November 2014, and preliminary calculations of the prevalence and incidence of individual
multifactorial diseases began in December 2014 todetermine whether there are sufficient numbers ofcases for statistical analysis.
As for the ethics agenda item discussed inaccordance with revisions made in February 2013
to the Japan Ethics Guidelines for Human Genome/
Gene Analysis Research, Dr. Ohishi explained
policies concerning how to deal with requests fromhealth examination participants for the withdrawal
of informed consent, as well as draft revisions forthe consent form concerning storage and use ofsamples, related explanatory note, and for the formof request for discontinuation. Animated disussions
were held, with committee Vice Chairman Hiraku
Takebe serving as moderator. As a result of the
discussions, it was decided that the draft revisions
required further review, and we were requested
to reconsider them based on the opinions of thecommittee members. The meeting concluded witha summary delivered by Dr. Shimao and closing
remarks and words of appreciation by RERF Vice
Chairman Roy E. Shore.
Due to our efforts to achieve a participation rateof 80% (about 10,000 individuals), the numberof participants visiting RERF to undergo healthexaminations in the first examination cycle of thelongitudinal clinical study is projected to exceed
9,500. We will continue our efforts to ensure thatthe study participants understand the significanceof the longitudinal clinical study and encourage

Fourth meeting of the Scientific and Ethics Committee for
the Clinical Study of the F1 Offspring of A-bomb survivors
held at the Hiroshima Laboratory

RERF Update Volume 25, Issue 2, 2014

update 12

Conference and Workshop Reports
their continued involvement in the study by sending letters requesting participation and contacting
them by telephone.
Members of the Scientific and Ethics Committee for the Clinical Study of the F1 Offspring of A-bomb Survivors
Dr. Tadao Shimao (Chairman), Consultant, Japan
Anti-Tuberculosis Association
Dr. Hiraku Takebe (Vice Chairman), Fellow, Kinki
University Atomic Energy Research InstituteDr. Hirotsugu Ueshima, Special Contract Professor, Lifestyle-Related Disease Prevention Center, Shiga University of Medical Science
Dr. Takashi Kawamoto, Professor, Graduate
School of Education, The University of Tokyo
Mr. Shinsuke Kimura, Attorney, Kimura Shinsuke
Law OfficeDr. Hideo Sasaki, Professor, Department of Nutritional Sciences, Faculty of Human Ecology,
Yasuda Women’s University
Dr. Steve Wing, Associate Professor, Departmentof Epidemiology, School of Public Health, University of North Carolina
Dr. Kazuo Tajima, Director, Aichi Cancer Center
Research InstituteDr. Masao Tomonaga, Director, Japanese Red
Cross Nagasaki Atomic Bomb Hospital
Dr. Taisei Nomura, Professor Emeritus, Osaka
University
Dr. Norihiko Hayakawa, Professor Emeritus,
Hiroshima University
Dr. Yoshimitsu Fukushima, Dean, Shinshu University School of Medicine
Dr. Katsumi Furitsu, Assistant Professor, Department of Genetics, Hyogo College of Medicine
Dr. Eiji Maruyama, Professor, Graduate School ofLaw, Kobe University
RERF Participants
Dr. Toshiteru Okubo, Chairman
Dr. Roy E. Shore, Vice Chairman and Executive
Director
Mr. Takanobu Teramoto, Executive Director
Dr. Robert L. Ullrich, Associate Chief of Research
Dr. Kazunori Kodama, Chief Scientist
Mr. Eiji Akimoto, Chief of Secretariat
Mr. Douglas C. Solvie, Associate Chief of Secretariat
Members, Working Group for the Clinical Study ofthe F1 Offspring of A-bomb Survivors
Research Scientists, Department of Clinical Studies

Fifth Epidemiological Training Workshop for Biologists
Ritsu Sakata, Associate Senior Scientist
Department of Epidemiology, Hiroshima
The fifth Epidemiological Training Workshop
for Biologists, sponsored by the Council of Radiation Effects Research Organizations*, was held
August 25–26, 2014, at the Auditorium of theHiroshima Laboratory, and 34 people, 11 from
RERF, attended. During the reception at last year’s
workshop, there was a request that young researchers be given more opportunities to express theiropinions during workshop sessions. Thus, at thestart of this year’s event, young researchers andself-designated “beginners” were encouraged to
speak up throughout the workshop events. Even
when a discussion extended beyond its scheduled
time, this year’s event did not conclude until questions and debate had finished.
To help establish a common vocabulary for all
attendees, on the first day Dr. Ritsu Sakata, Associate Senior Scientist, Hiroshima Department of
Epidemiology, gave a lecture titled “Epidemiology
for non-specialists,” and explained epidemiologiReturn to Table of Contents

cal terms and described typical research methods.
This was followed by the lectures “Recent resultsfrom the Life Span Study” (Dr. Sakata), “Genetic
effects in atomic bomb survivors” (Dr. Yoshiaki
Kodama, Chief, Department of Genetics), and“The past, present, and future of radiation effects
studies among the atomic bomb survivors exposed
in utero” (Dr. Nori Nakamura, Consultant, Department of Genetics), in which were presented
research results of the RERF follow-up study populations of the Life Span Study (LSS), the studyof children of A-bomb survivors, and the in utero
study.
In a subsequent lecture titled “Natural radiation risk for leukemia,” Dr. Atsuko Sadakane,
Associate Senior Scientist, Hiroshima Departmentof Epidemiology, explained appropriate ways ofreading and understanding epidemiological papers.
In a lecture titled “Radiation exposure and thyroid
cancer,” Dr. Misa Imaizumi, Chief, Division of
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update 13

Conference and Workshop Reports
Radiology, Chief, Division of Clinical Laboratories, Nagasaki Department of Clinical Studies,
spoke about thyroid cancer, a topic of special
interest given the nuclear power plant accident inFukushima.
Following the first day’s meetings, most workshop participants attended a reception, which Chief
Scientist Kazunori Kodama also joined. The gathering’s enjoyable atmosphere allowed for relaxedinteraction to take place among the researchers.
On the second day, three new topics wereaddressed, building on discussions arising fromthe basic knowledge presented on the opening day.
Dr. Nakamura presented two lectures: “What is themeaning of ‘no indication of an age at exposure
effect on breast cancer’?,” and “Does radiationinduce cancer or accelerate cancer onset?” Dr.
Otsura Niwa, a specially appointed professor at
Fukushima Medical University, gave a talk titled“Biological science paradigms from radiation biology.”
This series of workshops aims at enhancing
communication between biological and epidemiological researchers based on the use of commonly
understood, rather than arcane, terminology. Now,
after several workshops have been held, the gatherings feature participants actively raising questions
and speaking their minds, hinting at the fruitfulresult of the consecutive workshops. Even so, midway through the event this time, only researchers
well versed in RERF studies participated in thediscussions. At that point, we felt it necessary toprovide more descriptions using general terms, notthe specialized language we use typically, and to
give appropriate explanations in order to ensurethat participants attending the workshop for the
first time could also join in the dialogue.
At the close of the workshop, opinions weresought about the future of this workshop series.
Attendees identified a variety of goals and objec-

tives for their participation and suggested a number of desirable topics for the future, including
themes such as “how radiation dose estimates are
obtained,” “carcinogenesis research,” “a mathematical model of carcinogenesis,” and “comparisonswith epidemiological research in other fields.” It
was also suggested that attendees receive practical training in analysis. There were requests fora repeat of explanations of basic epidemiology
and appropriate techniques for reading and understanding epidemiological papers. Some attendees
asked about the possibility of having a retreat or
expanding the schedule, but considering the necessary budget and the inconvenience for participants
traveling from afar, it may be necessary to continue
the current practice of ending the workshop after a
day and a half. We need to review alternatives, suchas distributing basic information on the website or
sending relevant materials in advance to make surethat participants can study beforehand, and allocating more workshop time for requested topics.
I hope to modify the format of the next workshop based on the opinions and requests raised bythis year’s attendees. I would like to express myappreciation to all those who participated, those
who gave lectures, and the staff members of theGeneral Affairs Section and the Department of
Epidemiology who supported the holding of theworkshop.
*The Council of Radiation Effects Research Organizations was established to develop understanding amongradiation research organizations and strengthen their
alliance. The Council includes representatives of theInstitute for Environmental Sciences, Kyoto University,
Nagasaki University, Hirosaki University, Hiroshima
University, Fukushima Medical University, National
Institute of Radiological Sciences, and Radiation
Effects Research Foundation (arranged according to theJapanese syllabary).

Participants of the fifth Epidemiological Training Workshop for Biologists

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RERF Update Volume 25, Issue 2, 2014

Conference and Workshop Reports

update 14

Meeting of the Conference on Radiation and Health Held in Las Vegas
Harry M. Cullings, Chief
Department of Statistics
from a more global perspective. These viewpoints
The Conference on Radiation and Healthinclude the laboratory, the clinic, and epidemio(CRH), formerly the ASA Conference on Radialogic studies of populations exposed to ionizingtion and Health, recently held a successful meetingradiation from occupations, medical therapy, orSeptember 21–24, 2014, in conjunction with theenvironmental contamination. The research sciannual meeting of the Radiation Research Socientists in attendance were statisticians, epidemiety (RRS) in Las Vegas, Nevada, U.S.A. This isologists, physicians, risk assessors, psychologists,
a new affiliation for the CRH and its success wasbiologists, and physicists working in radiation
both important and auspicious for the conference’s
research and dosimetry.
future.
The meeting seems to have been a clear success.
The CRH was affiliated with the American StaThere were joint sessions, and attendees could partistical Association (ASA) for many years, starting
ticipate in both CRH and RRS sessions. There wasat its inception in 1981. For the first few years the
a complementarity in that the epidemiological andmeeting was held on a yearly basis at the Coolradiation protection emphases of the CRH fitted in
font Conference Center in Berkeley Springs, Westwell with the physical, molecular/biological, andVirginia, a small resort in the mountains northwest
radiation oncology emphases of the RRS meeting.
of Washington, D.C., and was often called the
In recent years, the CRH has also expanded its“Coolfont” meeting. It was a small, highly focused
portfolio to include travel support and mentoring
gathering held in a somewhat secluded area tofor young investigators (Early Stage Radiation
allow for maximal interaction among the particiInvestigators = ESRI).
pants. Over the years, it came to be held on a bianThis year’s CRH was supported by various
nual basis in various similarly secluded locations inorganizations including the U.S. Department of
the eastern and western U.S., but always under the
Energy and other federal agencies. RERF has long
aegis of the ASA. It was typically sponsored by abeen involved with and has supported the CRH,
number of organizations with an interest in promotand the author has been a member of the CRH
ing the scientific investigation of radiation healthorganizing committee for several years. This year,
effects, including various government agencies.
RERF contributed support in kind by supporting
After the 2012 meeting of the ASA-CRH in
travel for several invited speakers from RERF. The
Kennebunkport, Maine, the ASA decided to dismeeting was attended by numerous researchers
continue its involvement with the meeting, andfrom RERF, many of whom were invited speakers
the CRH organizing committee sought to affiliate
or presented posters at CRH, including Drs. Roy E.
with a new group that could provide the financial
Shore (Vice Chairman), Harry M. Cullings (Dept.
guarantees and other backing necessary to secureof Statistics), Eric J. Grant (Dept. of Epidemiola venue and arrange such a meeting. Fortunately,
particularly due to the diligence of organizers such as Dr. Dan Stram (University of Southern California), Dr. Lydia
Zablotska (University of California, San
Francisco), Dr. Cecile Ronckers (EmmaChildren’s Hospital/Academic Medical
Center, the Netherlands), and Dr. Alice
Sigurdson (U.S. National Cancer Institute), the CRH was able to arrange anaffiliation with the RRS and a meeting
held in conjunction with the society’s
annual meeting.
The purpose of the contemporary
CRH is to provide the latest information
on new methodologies and research in
the health effects of radiation exposure
from diverse perspectives with the goal
Dr. Kyoji Furukawa, Research Scientist, Statistics Dept., presenting at theof creating an understanding of the topic
Meeting of the Conference on Radiation and Health in Las Vegas
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RERF Update Volume 25, Issue 2, 2014

Conference and Workshop Reportsogy), Atsuko Sadakane (Dept. of Epidemiology),
Kyoji Furukawa (Dept. of Statistics), Ritsu Sakata(Dept. of Epidemiology), and Munechika Misumi(Dept. of Statistics). Other RERF researchers presented at RRS and were able to attend the CRH andjoint CRH-RRS sessions, including Drs. Robert L.
Ullrich (Associate Chief of Research), Kazunori
Kodama (Chief Scientist), Ikuno Takahashi (Dept.
of Clinical Studies), Norio Takahashi (Consultant,
Associate Chief of Research Office), and Yasunari
Satoh (Dept. of Genetics). The CRH organizers
graciously scheduled a late-breaking joint CRHRRS session on the recent joint RERF-NCI workon cancer incidence. There was also a joint CRHRRS session on Fukushima and Chernobyl, which
included an invited speaker from Keio University
in Japan, Dr. Yutaka Kato, who spoke on the psychosocial aspects of the earthquake, tsunami, andnuclear power plant disaster in Fukushima.
The conference keynote speaker, Dr. Flora
E. van Leeuwen, delivered the evening banquet address titled “From old radiation treatment
records to survivorship care plans: an exciting

update 15
journey.” The seven scientific sessions were titled(A) Radiation-induced long term non-cancer risks:
EU projects ‘CEREBRAD’ and ‘PROCARDIO,’(B) Solid cancer incidence among atomic bomb
survivors, updated analysis through 2009, (C) Lateeffects of radiotherapy: new dosimetric approaches
in epidemiologic studies, (D) CT scans and cancer risks: new results and methodological issues,(E) Genetic issues in radiation epidemiology, (F)Bridging mechanisms of radiation action at low
doses and human risk, and (G) Fukushima andChernobyl.
Although the nature of the CRH meeting maychange somewhat in future years, due to its being
collocated with another major scientific meeting,it appears that supporters of the CRH can look forward to more exciting meetings in the future.
The author is indebted to Dr. John B. Cologne,
Senior Scientist, Department of Statistics of RERF,
who amazingly had preserved a copy of the program of Coolfont IV, which he and the author
attended as graduate students 30 years ago, in
1984.

International Space Agencies Visit Hiroshima RERF to Further
Understanding of Health Effects from Radiation in Space
RERF recently had the opportunity to serve
as host for the annual meeting of the Multilateral
Radiation Health Working Group (RHWG) during
the period October 20–23, 2014. The roughly 20
RHWG members included personnel from the U.S.
National Aeronautics and Space Administration(NASA), the Japan Aerospace Exploration Agency(JAXA), the Canadian Space Agency (CSA), theEuropean Space Agency (ESA), and the RussianFederal Space Agency (FSA). As its aim is toinvestigate radiation and health issues, the RHWG
asked to consult with RERF to take advantage ofDr. Michael Barratt, MD/(NASA) Physician Astronaut, speaking via Skype to RHWG
and RERF participants about spaceflight
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RERF Update Volume 25, Issue 2, 2014

Conference and Workshop Reports
our internationally recognized expertise and leadership in this area.
The opening session of the meeting, October 20,
included welcoming remarks by RERF Chairman
Toshiteru Okubo and greetings by a JAXA representative. The highlight of the morning was a videoconference presentation provided by Dr. Michael
Barratt, MD/Physician Astronaut, NASA Johnson
Space Center, who spoke from the United States on
the theme of human spaceflight and his experienceson the International Space Station (ISS), including
the numerous challenges while working in spacesuch as radiation exposure, appropriate exercise,
food choices, viral infections, and limits to the kindof research that can be conducted on board.
Other presentations throughout that day’s briefings session involved mainly radiation and healthconsiderations in space, including a presentation by
JAXA on its radiation health activities. NASA thenspoke on the theme of space radiation health, protection, and operational support, and separately, on
its radiation health research portfolio, while ESA
presented on European activities related to radiation protection in space. CSA added information
about its radiation health activity reviews. In thelate afternoon, the RHWG working group members
visited Hiroshima Peace Memorial Park and thePeace Memorial Museum, followed by a receptionthat was hosted by RERF at a popular Westernstyle restaurant in the downtown of Hiroshima.
The following day, October 21, was dedicatedto presentations by RERF staff, starting with welcome remarks by Dr. Robert L. Ullrich, Associate Chief of Research. Dr. Kotaro Ozasa, Chief,
Epidemiology Department, introduced RERF and
its LSS and AHS cohorts; Dr. Harry M. Cullings,
Chief, Statistics Department, gave a presentationon the RERF dosimetry system; Dr. Eric J. Grant,
Assistant Chief, Epidemiology Department, spokeon radiation risks of breast and other solid cancers;
Dr. Ritsu Sakata, Associate Senior Scientist, Epidemiology Department, presented information about
her research into radiation risks of lung cancer
and stomach cancer, both with and without adjustment made for smoking; and Dr. John B. Cologne,
Senior Scientist, Statistics Department, spoke onradiation risk of liver cancer, including the aspects
of interaction, mediation, and uncertainty.
The meeting resumed following a lunch heldin the reception room of the RERF Hijiyama Hall.
Dr. Waka Ohishi, Chief, Clinical Studies Department, explained radiation risks of cardiovasculardiseases; Dr. Michiko Yamada, Chief, Division ofRadiology, Clinical Studies Department, elaborated
on radiation effects in relation to cognitive changes
and other central nervous system issues; Dr. Roy

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update 16
E. Shore, Vice Chairman and Executive Director,
spoke on issues in modeling radiation risks; and Dr.
Ullrich concluded the session with his elaborationof tissue quality factors derived from experimental
studies. The day ended on a relaxed note, with theparticipants and other support staff attending a dinner hosted by JAXA at a tofu restaurant in the local
Hijiyama area.
The third day, October 22, comprised RHWG
discussions about its administrative business andother items, in what was a closed session. The
fourth and final day, October 23, concluded ataround noon, after a review of the meeting agenda
and a discussion, followed by an informal media
gathering in the early afternoon at RERF that
centered on a presentation offered by Mr. Edward
Semones, NASA Spaceflight Radiation Health
Officer, NASA Johnson Space Center.
Mr. Semones’ presentation to the media focusedon the importance of RERF’s radiation healtheffects research in terms of NASA attempts toovercome the health impacts of exposure to ionizing radiation from the space environment, inparticular when considering its future aim to keep
humans in space over a long duration on suchprojects as its asteroid capture mission and manned
mission to Mars. Mr. Semones closed his presentation with the sentiment that by collaborating with
RERF, NASA and other such agencies can explore
space while reducing the impact of radiation healtheffects on astronauts.
The meeting provided RERF with an excellent
opportunity to showcase its detailed knowledgeof radiation health effects based on its research on
the health experience of the survivors of the atomic
bombings of Hiroshima and Nagasaki. We hope forcontinued collaboration with the RHWG and theserenowned space agencies in the future.

Mr. Edward Semones, NASA Spaceflight Radiation Health
Officer, addresses a group of journalists in a media forum
following conclusion of the RHWG meeting

RERF Update Volume 25, Issue 2, 2014

update 17

Science Articles

Inverse Associations between Obesity Indicators
and Thymic T-cell Production Levels in Aging
Atomic-bomb Survivors*
Kengo Yoshida
Department of Radiobiology/Molecular Epidemiology, RERF
*This article is based on the following publication:
Kengo Yoshida, Eiji Nakashima, Yoshiko Kubo, Mika Yamaoka, Junko Kajimura, Seishi
Kyoizumi, Tomonori Hayashi, Waka Ohishi, Yoichiro Kusunoki: Inverse Associations between
Obesity Indicators and Thymic T-cell Production Levels in Aging Atomic-bomb Survivors,
PLoS ONE 2014 (March); 9(3):e91985 (doi: 10.1371/journal.pone.0091985)

Study Findings
T-cell receptor excision circles, or TRECs, arecircular molecules of DNA excised from chromosomes when T cells are produced in the thymus.
They indicate new production of T cells, and their
numbers, which decrease with aging, represent
an immunological marker of thymic capacity to
produce naïve T cells. In this study, low TREC
numbers were found to be associated with diseases
related to high body mass index (BMI) and obesity, such as diabetes and fatty liver. These results
suggest the possibility that reduction of immunological competence associated with aging may befurther accelerated by obesity.
Explanation
The production of T cells, which are blood cellswith immunological functions, starts in the bonemarrow and then continues in the thymus. In previous immunological studies at the Radiation Effects
Research Foundation (RERF), the number of naïve
T cells in peripheral blood was found to decrease
after radiation exposure, leading to a hypothesis
describing the mechanism behind this decline as
the effect of radiation exposure on the ability of thethymus to produce naïve T cells.
Based on animal model studies conducted inrecent years, obesity has been linked to the functional decline of the T-cell immune system associated with aging. However, findings based on studies of human populations were extremely limited.
We therefore conducted a study of RERF’s
Adult Health Study (AHS) participants, whose
health has been followed for many years, in orderto determine the effects of age, radiation dose, andobesity on indicators of thymic capacity to produce

Figure. Relationship of naïve T-cell production levels to aging and obesity
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RERF Update Volume 25, Issue 2, 2014

Science Articlesnaïve T cells (TREC number).Note
Note) TRECs, excised from chromosomes when
T cells are produced in the thymus, are by-products of this process and characteristic of newly
produced naïve T cells. Because they are notreplicated by subsequent cell divisions in blood,
TREC number can be used as an indicator ofthymic capacity to produce naïve T cells.
1. Objectives
The objectives of the study were to examine
the relationship between radiation exposure and
TREC number, an indicator of thymus capacity to
produce naïve T cells, and to determine the association of TREC number to obesity indicators anddiseases associated with obesity, after adjusting forthe effects of age, sex, radiation exposure, alcohol
consumption, and smoking.
2. Methods
Among 1,073 A-bomb survivors who participated in the AHS from 2003 to 2009, we measured
TREC number per 10,000 CD4 T cells (helper T
cells, which control immune response) and per
10,000 CD8 T cells (killer T cells, which detect anddestroy infected or transformed cells) in peripheral
blood, utilizing polymerase chain reaction. We
used information obtained from the AHS on BMI
as an indicator of obesity, total cholesterol level,
HbA1c level (which represents blood glucose levels over the previous 2–3 months), and CRP level(an indicator of inflammation), as well as diseases
related to obesity (type 2 diabetes, fatty liver, andhypertension), alcohol consumption, and smoking.
We conducted linear regression statistical analysis,
with adjustment made for age, sex, radiation dose,amount of alcohol consumed, and number of cigarettes smoked.

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update 18
3. Results(1) Relationship between TREC number and age
Subject ages ranged from 58 to 109 years. Evenin this elderly population, TREC number in CD4
and CD8 T cells decreased with age (p < 0.001 in
terms of significance).
(2) Relationship between TREC number and radiation dose
Radiation exposure had no effect on TREC
number in either CD4 or CD8 T cells. We also
conducted a preliminary analysis by selecting,from among the 1,073 subjects, a high-dose group(radiation dose of at least 1 Gy) and a control group(radiation dose of less than 5 mGy), matched bysuch factors as age and sex, and then comparing thetwo groups. No difference in TREC number wasobserved in relation to radiation dose.
(3) Association between TREC number and obesity indicators
TREC number in CD4 and CD8 T cells significantly decreased with an increase of HbA1c and
CRP levels (p < 0.05). TREC number also tended
to be inversely associated with BMI. Further,
TREC number was small in cases of diabetes andfatty liver (p < 0.05).
In this study, no association between TREC
number and radiation exposure was observed,
but TREC number was found to decrease withan increase in the levels of obesity indicators in ahuman population. This result provides evidence tosuggest that obesity may accelerate immunological aging in humans. Because obesity is known toincrease the risk of several age-related diseases,
attenuated immune competence due to the reduction in naïve T-cell production may be one of thedevelopmental mechanisms of diseases associatedwith obesity.

RERF Update Volume 25, Issue 2, 2014

update 19

Science Articles

A Novel RET Rearrangement (ACBD5/RET) by Pericentric Inversion, inv(10) (p12.1;q11.2), in Papillary
Thyroid Cancer from an Atomic-bomb Survivor
Exposed to High-dose Radiation*
Kiyohiro Hamatani
Department of Radiobiology/Molecular Epidemiology, RERF
*This article is based on the following publication:
Kiyohiro Hamatani, Hidetaka Eguchi, Kazuaki Koyama, Mayumi Mukai, Kei Nakachi, andYoichiro Kusunoki: A Novel RET Rearrangement (ACBD5/RET) by Pericentric Inversion,inv(10) (p12.1;q11.2), in Papillary Thyroid Cancer from an Atomic-bomb Survivor Exposed toHigh-dose Radiation. Oncol Rep 2014 (August); 32:1809–14 (doi: 10.3892/or. 2014.3449)

Study Findings
Our analysis has shown that a novel type of RET
rearrangement (ACBD5-RET fusion gene) that was
identified in papillary thyroid cancer (PTC) cellsof an atomic bomb survivor constitutively activates
the MAPK-signaling pathway* and can lead to thedevelopment of tumors, as is the case with othertypes of RET fusion genes.
*The term “signaling pathways” denotes themechanism by which protein kinases phosphorylate (in other words, activate) other protein kinases and cascade signals downstream.
The MAPK-signaling pathway is one such
pathway.
Explanation
Through chromosomal inversion or translocation, radiation-related PTC cases such as adult PTC
among A-bomb survivors and childhood PTC thatdeveloped after the Chernobyl nuclear accident
often exhibit rearranged RET genes, that is fusion
genes such as CCDC6-RET and NCOA4-RET,
between the tyrosine kinase domain of the RET
gene and other gene sites. These fusion genes are
believed to be significantly involved in papillary
thyroid carcinogenesis.
We analyzed the structure and function of anovel RET rearrangement (ACBD5-RET fusiongene) found in the PTC of an A-bomb survivor
exposed to high-dose radiation.
1. Objectives
To elucidate, through in vitro and in vivo experiments, whether the ACBD5-RET fusion gene foundin the PTC of the A-bomb survivor activates the
MAPK-signaling pathway and induces tumor forReturn to Table of Contents

mation.
2. Methods(1) Expression vectors, i.e., plasmid DNA with apromoter sequence needed for gene expression,containing cDNA (DNA synthesized from an
RNA template by reverse transcriptase andcomplementary to mRNA) of the ACBD5-RET
fusion gene were introduced into mouse
NIH3T3 cells (immortalized fibroblasts established from mouse skin cells). This process wasundertaken to determine, using Western-blotting*, whether phosphorylation (or, activation)of protein kinase in the MAPK-signaling pathway is enhanced.
*Western-blotting is an analytical technique fordetecting specific proteins. It uses gel electrophoresis to separate protein samples, transfers
and fixes them to a membrane (filter paper for
blotting), and identifies specific proteins basedon antigen-antibody reactions.
(2) We introduced the cDNA of the ACBD5-RET
fusion gene into NIH3T3 cells, injected theresultant NIH3T3 cells subcutaneously into
nude mice, and examined tumor formation toevaluate the tumorigenicity of the ACBD5-RET
fusion gene.
3. Results(1) We determined that the ACBD5-RET fusion
gene is formed via inverse binding between abreak point in the tyrosine kinase domain of the
RET gene located in the long arm of chromosome 10 and the 5’ end of the ACBD5 genelocated in the short arm of the same chromosome (pericentric inversion) (see Figure).
RERF Update Volume 25, Issue 2, 2014

update 20

Science Articles

Figure (Inversion)
p15
p14
ACBDS gene 5’ p13
p12
3’ p113’

5’ACBDS-RET fusion gene

3’

RET gene 5’ q11
q21

Tyrosine kinase domain q22

Centromere
動原体

q23
q24
q25
q26

Chromosome 10

This figure shows the ACBD5-RET fusion gene formed by a pericentric inversion. Inversions occur when a chromosome breaks in two places and the resulting
fragment of DNA is inverted and re-inserted into the chromosome. Inversions thatinvolve the centromere (the constricted region of the chromosome) are called pericentric inversions.
(2) Accelerated phosphorylation of protein kinase
was observed in the NIH3T3 cells with an
ACBD5-RET fusion gene.
(3) After injection into the nude mice, the NIH3T3
cells with an ACBD5-RET fusion gene continued proliferating and formed tumors.
This study showed that the ACBD5-RET fusion
gene found in the PTC of an A-bomb survivor is

Return to Table of Contents

significantly involved in papillary thyroid carcinogenesis, as is the case with other RET fusion genes
such as CCDC6-RET and NCOA4-RET. RET generearrangement induced either directly or indirectly
by radiation is therefore suggested to be closely
involved in papillary thyroid carcinogenesis among
PTC patients exposed to relatively high doses ofradiation.

RERF Update Volume 25, Issue 2, 2014

update 21

Science Articles

Linkage between Dendritic and T-cell
Commitments in Human Circulating
Hematopoietic Progenitors*
Seishi Kyoizumi
Department of Radiobiology/Molecular Epidemiology, RERF
*This article is based on the following publication:
Seishi Kyoizumi, Yoshiko Kubo, Junko Kajimura, Kengo Yoshida, Tomonori Hayashi, Kei
Nakachi, Lauren F. Young, Malcolm A. Moore, Marcel R.M. van den Brink, Yoichiro Kusunoki: Linkage between Dendritic and T-cell Commitments in Human Circulating Hematopoietic Progenitors. J Immunol 2014 (June); 192(12):5749–60 (doi: 10.4049/jimmunol.1303260)

Study Findings
Dendritic cells (DCs) play an indispensable rolein the differentiation and functional expression of
T cells. These two types of cells differentiate fromhematopoietic stem cells (HSCs), and the current
study finds that the frequencies of T-cell and DC
precursors are significantly linked with each otherin stem cells existing in blood, whereas they are notlinked to the precursor frequency (PF) of naturalkiller (NK) cells.
Explanation
1. Objectives
DCs are a type of leukocyte with dendrites. They
initiate an adaptive immune response by conveying
antigen information about viruses and bacteria thathave invaded the body to T cells, which serve as a‘control tower’ for the adaptive immune response.
DCs also prevent the generation of self-antigenresponsive T cells in the thymus as a negative
selection. Because self-antigen-responsive T cells
recognize substances that make up their host bodyas antigens, these cells are detrimental. DCs arethus essential for the differentiation and functional
expression of T cells. Based on this understanding,we hypothesized that there may be a correlation
between the potency of HSCs to differentiate into
DCs and their potency to differentiate into T cells,suggesting a linkage between DC and T-cell commitments. (HSCs are the least differentiated cells
that can give rise to all blood cell types, are long
lived, and have the ability to self-replicate.) Verifying this hypothesis was considered to provide
important findings for ongoing studies of A-bomb
survivors involving T-cell progenitors and DCs.
DCs can be classified as conventional DCs (cDCs,
which inform T cells of antigens to initiate direct
attack) or plasmacytoid DCs (pDCs, which proReturn to Table of Contents

duce type-I interferon and induce anti-viral infection immunity). In the present study, we analyzed
DC progenitors of both types.
2. Methods
It is possible to separate hematopoietic progenitor cells (HPCs, cells with the potency to differentiate into T cells and DCs) in human peripheral
blood using a cell sorter, and then to differentiate
HPCs into T cells and NK cells using the culture
method reported in Kyoizumi et al.: J Immunol
2013; 190:6164–72. NK cells are a type of cytotoxic lymphocyte that is important for the innate
immune system. Since the present study confirmedthat this culture method could induce differentiation of HPCs into DCs, we used it as an experimental system to simultaneously assay T cells, NK
cells, and DC progenitors. Blood samples were collected, based on informed consent, from 20 RERF
in-house volunteer donors aged 26–65 years, andwe measured the PFs of T cells and NK cells,
as well as cDCs and pDCs, based on the culture
method, to examine correlations among the PFs ofthese cells. Furthermore, we examined the potencies of single precursor cells to differentiate into
T cells and NK cells, as well as cDCs and pDCs,
based on precursor cell clonal culture.
3. Results(1) The PFs of cDCs and pDCs in HPCs were
found to correlate significantly with T-cell PFs,
but not with NK-cell PFs.
(2) The precursors producing T cells and NK cells
were classified into clones producing T/NK
dual-, T single-, and NK single-lineage precursors. The clones of T/NK dual- and T singlelineage precursors produced cDCs or pDCs athigh frequencies. The clones of NK single-linRERF Update Volume 25, Issue 2, 2014

update 22

Science Articles
eage precursors, however, produced very few
cDCs or pDCs.
4. Consideration and Conclusion
These findings show that T-cell and DC commitments are linked with each other, as indicatedwith the green lines below. On the other hand,
this research suggests that NK-cell commitment
is induced independently from DC commitment.

Long-lived HSC

T/NK/DC duallineage precursor

In addition, the linkage between T-cell and DC
precursors might be intrinsically imprinted in longlived HSCs existing in bone marrow that are selfreplicating, since the T-cell and DC progenitors in
the human body have short life spans.
Note: Progenitors are specific cells, generated fromstem cells, that are able to differentiate into more
specific types of cells.

T/NK
dual-lineage
precursor

NK cell

T cellT/DC commitment
NK commitment

cDC

DC
pDC

Return to Table of Contents

RERF Update Volume 25, Issue 2, 2014

Human Interest Notes

update 23

George Takei Visits Hiroshima RERF for Filming of
Takei’s Take Involving Technology in Japan
exact location due to development of the city thatOn June 10, 2014, the Radiation Effects
has taken place since the A-bombing of Hiroshima
Research Foundation (RERF) in Hiroshima wason August 6, 1945.
very fortunate to host George Takei and his film
To view all four of Mr. Takei videos about
and support crew while they filmed a segment forJapanese technology and his thoughts about both
his series of AARP-sponsored YouTube videos,historical and modern-day Japan, please accessTakei’s Take.
them through Facebook at “Radiation Effects
Mr. Takei is a director, author, and actor,
Research Foundation” or by clicking the Facebook
originally known for his role as Lt. Sulu in thepage link on the front page of our website.
American television series Star Trek, which first
RERF studies the effects of radiation on healthaired in the late 1960s. More recently, Mr. Takei’sin the hope that, in the future, radiation technology
involvement in social media has brought him huge
will only be used for peaceful purposes. We arenumbers of followers, due to frequent postings ofprofoundly grateful to Mr. Takei for his efforts tosocial commentary and humor on his Facebook andhelp us more broadly convey information about theTwitter accounts. He has been involved in politics,
work taking place at RERF.
championed gay rights and other issues, and won
several awards for his work on human rights andJapanese–American relations, including his workwith the Japanese American National Museum,located near the downtown area of Los Angeles.
In this season of the series, Mr. Takei traveled around the globe to explore and experience
technology that is changing the world. We werethankful that he chose to stop by RERF for a feature series on Japan, which included an interview
with Dr. Harry M. Cullings, Chief, Department of
Statistics, related to a revised mapping system for
more accurately identifying survivor locations at
the time of the atomic bombings.
Dr. Cullings explained to Mr. Takei and his crew
the key advantages of Geographical Information
System (GIS) technology, which is used at RERF
to obtain more precise locations of survivors at theDr. Harry Cullings, Chief, Statistics Dept., explaining GIS
time of the bombings and thus enable more accutechnology to George Takei (left) during interview
rate assessment of the radiation dosesthat the survivors received.
For Mr. Takei, though, the visit to
RERF was also personal: some of his
relatives survived the atomic bombingof Hiroshima. In the second in thisseries of videos, Dr. Cullings showsby GIS image the estimated locationsof Mr. Takei grandparents’ and aunt’s
homes in Hiroshima at the time of the
A-bombing of that city (see photo atright). Mr. Takei goes on to describe
the destructive power of the atomic
bombs and their impact on the lives of
his own relatives. In the third episode,Mr. Takei, together with his cousin,
try to locate their grandparents’ home,
GIS image showing locations of the homes (represented by red circles) of
only to fall short of identifying the
George Takei’s relatives
Return to Table of Contents

RERF Update Volume 25, Issue 2, 2014

update 24

Facts and Figures

Neutrons from the Atomic Bombs
in Hiroshima and Nagasaki
Harry M. Cullings, Chief
Department of Statistics

mass of tissue suspended in air represented only
about 9 mGy from neutrons and 530 mGy fromgamma rays.2 The energy distribution of neutronsin Hiroshima is shown in the figure, for intervalsof energy into which neutrons are grouped forcomputational purposes in DS02 (“energy bins”). It
can be seen that most of the dose is associated withneutrons in the energy range of about 0.5 to 2 MeV.
Because neutrons are more rapidly attenuatedby passage through air than are gamma rays, theneutron absorbed dose to a small mass of tissuesuspended in air, as a % of the gamma-ray dose,
decreases with distance. It ranges from about 5%
at 1 km in Hiroshima to about 0.2% at 2.5 km.3 In
addition, although gamma rays are not attenuatedmuch by the human body, neutrons are strongly
attenuated by the body because of mechanical collisions between neutrons and the protons that constitute nuclei of the hydrogen atoms in tissue. Thus,
the neutron dose as a fraction of gamma-ray dose
for a deep organ such as the colon is much smaller
than for a superficial organ such as the skin or thelens of the eye, ranging from < 1% at 1 km to about
0.03% at 2.5 km.3
In Nagasaki, neutron doses as a fraction of

The direct radiations from the atomic bombs
in Hiroshima and Nagasaki, which are the basisof the dose estimates for individual survivors thatare used in all RERF studies, consisted of neutrons
and gamma rays. Although for each survivor theamount of energy deposited in the body (absorbed
dose) from neutrons was much less than that fromgamma rays, there has been enduring concern
about neutrons, because it is well known thatneutrons create more biological effect per unit ofabsorbed dose than do gamma rays (greater radiobiological effectiveness, or “RBE”). Here we givesome key numbers related to neutrons, particularly
relative to gamma rays, which may be helpful informing a numerical perspective on the importanceof neutron vs. gamma-ray dose for the atomic
bomb survivors.
The number of neutrons and gamma rays passing through a given cross-sectional area was verylarge: for example, at 1.5 km from the hypocenter
in Hiroshima there were about 2.2 billion neutronsand 155 billion gamma rays per square centimeterof cross-sectional area, or about 70 times as many
gamma rays as neutrons.1 However, as large asthese numbers may sound, absorbed dose to a small

Energy Distribution of Hiroshima Neutron Free-In-Air Kerma at 1500 m
0.0025

Energy in bin, gray

0.002

0.00150.001

0.0005Return to Table of Contents

18.25

14.55

13.3

11.65

9.5

7.8

5.7

4.4

2.7

2.05

0.825

0.135

0.03850.016

0.00230.000340.000020.0000021

0.000000205

0Energy bin midpoint, MeVRERF Update Volume 25, Issue 2, 2014

Facts and Figures
gamma-ray doses tend to be several times smaller
than in Hiroshima. Thus, it is really only the mostproximal survivors (those nearest the hypocenter)
in Hiroshima who had neutron doses that equaled asubstantial fraction of their gamma-ray doses.
All of these considerations about the small sizeof neutron doses relative to gamma-ray doses areoffset to some extent by the RBE that is typicallyused for neutrons. RERF has tended to use a constant RBE of ten (10) in most of its major publications, but constant values as high as twenty (20)have been advocated by some investigators. Furthermore, dose-dependent RBEs that take on values
approaching 100 at very low doses and decrease
with increasing dose have been advocated, basedon the curvature in the gamma-ray dose response
for many biological endpoints in experimental
radiation biology. However, at the low doses wheresuch large values of the variable RBEs would
apply, the neutron doses received by survivors were
extremely small relative to the gamma-ray doses,
as indicated above. Therefore, the choice of RBE
among the alternatives just described does not havea major effect on risk estimates, as explained in

Return to Table of Contents

update 25
detail in a new paper recently published in Radiation Research.4

References
1. Egbert SD, Kerr GD, Cullings HM. DS02 fluence spectra for neutrons and gamma rays at
Hiroshima and Nagasaki with fluence-to-kerma
coefficients and transmission factors for sample
measurements. Radiat. Environ. Biophys. 48(4);311-25 (2007). Erratum in Radiat Environ Biophys. 50(2); 329–33 (2011).
2. Table D2, Chapter 3, DS02 Report. Available
online at http://www.rerf.jp/library/archives_e/scids.html.
3. Figure 7, Cullings HM, Fujita S, Funamoto S,
Grant EJ, Kerr GD, Preston DL. Dose estimation for atomic bomb survivor studies: its evolution and present status. Radiat. Res. 166(1 Pt
2):219–54 (2006).
4. Cullings HM, Pierce DA, Kellerer AM.
Accounting for Neutron Exposure in theJapanese Atomic Bomb Survivors. Radiat. Res.
(2014 Nov 19) [Epub ahead of print].

RERF Update Volume 25, Issue 2, 2014

Recent Publications

update 26

Recent Publications

Kyoizumi S, Kubo Y, Kajimura J, Yoshida K,
Hayashi T, Nakachi K, Young LF, Moore MA,
van den Brink MRM, Kusunoki Y: Linkage
between dendritic and T cell commitments inhuman circulating hematopoietic progenitors. J
Immunol 2014 (June); 192(12):5749–60. (RERF
Report 7-13)(Japanese): the original article is in Japanese

Asakawa J, Kamiguchi Y, Kamiya K, Nakamura N:
Mutagenic effects of ionizing radiation on immature rat oocytes. Radiat Res 2014 (October);
182(4):430–4. (RERF Report 6-14)
Furukawa K: The importance of study designs andstatistical analysis in epidemiology. Clinical Calcium 2014 (May); 24(5):703–10. (Japanese)
Furukawa K, Preston DL, Misumi M, Cullings
HM: Handling incomplete smoking history datain survival analysis. Stat Methods Med Res 2014
(October 26). doi: 10.1177/0962280214556794[Epub ahead of print] (RERF Report 4-13)
Hamatani K, Eguchi H, Koyama K, Mukai M,
Nakachi K, Kusunoki Y: A novel RET rearrangement (ACBD5/RET) by pericentric inversion, inv(10) (p12.1;q11.2), in papillary thyroid cancerfrom an atomic bomb survivor exposed to highdose radiation. Oncol Rep 2014 (November);32(5):1809–14. (RERF Report 4-14)
Imaizumi M, Furukawa K: Thyroid disorders in
Hiroshima and Nagasaki atomic-bomb survivors.
Hiroshima Igaku [J Hiroshima Med Assoc] 2014
(April); 67(4):284–6. (Proceedings of the 54th
Late A-bomb Effects Research Meeting, 2013)(Japanese)
Ito R, Hamatani K, Yano S, Shinohara T, Takahashi
K, Yasui W, Nakachi K, Kusunoki Y: Microsatellite instability (MSI) and MLH1 alteration incolorectal cancer among A-bomb survivors.
Hiroshima Igaku [J Hiroshima Med Assoc] 2014
(April); 67(4):356–60. (Proceedings of the 54th
Late A-bomb Effects Research Meeting, 2013)(Japanese)
Kusumoto S, Kawano H, Makita N, Ichimaru S,
Kaku T, Haruta D, Hida A, Sera N, Imaizumi M,
Nakashima E, Maemura K, Akahoshi M: Rightbundle branch block without overt heart disease
predicts higher risk of pacemaker implantation:
The study of atomic-bomb survivors. Int J Cardiol 2014 (June); 174(1):77–82. (RERF Report
6-13)

Nakamura N: How to explain low dose risks to the
public. Hiroshima Igaku [J Hiroshima Med
Assoc] 2014 (April); 67(4):294–7. (Proceedingsof the 54th Late A-bomb Effects Research Meeting, 2013) (Japanese)
Sugiyama H, Misumi M, Kishikawa M, Iseki M,
Yonehara S, Hayashi T, Soda M, Tokuoka S,
Shimizu Y, Sakata R, Grant EJ, Kasagi F,
Mabuchi K, Suyama A, Ozasa K: Skin cancer
incidence among atomic bomb survivors from1958 to 1996. Radiat Res 2014 (May);
181(5):531–9. (RERF Report 16-12)
Taga M, Mukai M, Koyama K, Ito R, Misumi M,
Nakachi K, Kusunoki Y, Yasui W, Hamatani K:
Analysis of ALK gene rearrangements in lungadenocarcinomas of atomic-bomb survivors—A
pilot study. Hiroshima Igaku [J Hiroshima Med
Assoc] 2014 (April); 67(4):361–4. (Proceedingsof the 54th Late A-bomb Effects Research Meeting, 2013) (Japanese)
Tatsukawa Y, Cologne JB, Yamada M, Ohishi W,
Hida A, Furukawa K, Takahashi N, Nakamura N,
Ozasa K, Akahoshi M, Fujiwara S, Shore RE:
Association between parental radiation exposure
and prevalence of multifactorial diseases: F1
Clinical Health Study (2nd Report). Hiroshima
Igaku [J Hiroshima Med Assoc] 2014 (April);67(4):375–8. (Proceedings of the 54th Late
A-bomb Effects Research Meeting, 2013) (Japanese)
Zheng W, et al. (RERF: Ozasa K, Ohishi W,
Grant EJ): Burden of total and cause-specificmortality related to tobacco smoking among
adults aged ≥45 years in Asia: A pooled analysis of 21 cohorts. PLoS Med 2014 (April);11(4):e1001631.

Kyoizumi S: T-cell receptor mutation assay formonitoring human genotoxic exposure. Sierra
LM, Gaivao I, eds. Genotoxicity and
DNA Repair: A Practical Approach. New York:
Humana Press; 2014, pp 159–67.

Return to Table of Contents

RERF Update Volume 25, Issue 2, 2014

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