Table of Contents
From the Editors ......................................................................................................................................... 1
Letters to the Editors ................................................................................................................................... 2
RERF News
Responses to the Fukushima Dai-ichi Nuclear Power Plant Crisis ....................................................... 2
The First Board of Councilors Meeting Held in Hiroshima.................................................................. 5
Local Liaison Council Meetings in Hiroshima and Nagasaki............................................................... 6
The First Public Lectures for Citizens Held in Nagasaki ...................................................................... 6Open House Events in Hiroshima and Nagasaki................................................................................... 7
RERF and Fukushima Medical University Signs a Collaborative Agreement ...................................... 8
Visit by Scientists from IAEA ............................................................................................................... 8
Visit by Ambassador of Japan to the Conference on Disarmament ...................................................... 9
Staff News ........................................................................................................................................... 10
Visiting Student Researchers ............................................................................................................... 10
Recognition Received by an RERF Scientist ...................................................................................... 11
Conference and Workshop Reports
The 52nd Meeting of the Late A-bomb Effects Research Association Held in Hiroshima,by Kanya Hamasaki......................................................................................................................... 12
The Second Epidemiological Training Workshop for Biologists, by Nori Nakamura ........................ 13
The 14th International Congress of Radiation Research, by Evan B. Douple .................................... 14
Visit to RERF by Dr. Salerno of the National Academies, by Evan B. Douple .................................. 15
Science Articles
Generation of Novel and Versatile Recombinant Cell Systems That Detect and Measure
Genetic Effects of Radiation, by Asao Noda ................................................................................... 17
Effects of Radiation Exposure and Hepatitis Virus Infection on Risk of Hepatocellular
Carcinoma among Atomic Bomb Survivors, by Waka Ohishi ........................................................ 21
Lifetime Risk of Stroke and Impact of Hypertension: Estimates from the Adult Health Studyin Hiroshima and Nagasaki, by Ikuno Takahashi ............................................................................ 27
Human Interest Notes
Unveiling Ceremony of Monument Honoring Barbara Reynolds....................................................... 30
Report on the Health Examinations for A-bomb Survivors in the U.S., by Akihiko Suyama ............ 32
In Memoriam: Mrs. Ruth W. Beebe .....................................................................................................34
Facts and Figures ...................................................................................................................................... 35
Research Protocols and Publications
Research Protocols Approved in May–October 2011 ......................................................................... 36
Recent Publications ............................................................................................................................. 37

This newsletter is published by the Radiation Effects Research Foundation (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 Ministry of Health, Labour and Welfare andthat of the United States through the National Academy of Sciences under contract with the
Department of Energy.
RERF conducts research and studies—for peaceful purposes—on the medical effects of radiation on humans with a view toward contributing to the maintenance of the health and welfare of
atomic-bomb survivors and to the enhancement of the health of all mankind.
Editor-in-Chief: Evan B. Douple, Associate Chief of ResearchTechnical Editor: Yuko Ikawa, 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 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: www.rerf.jp

1

From the Editors

From the Editors
Welcome to RERF Update!
As efforts continue to try to bring the three
Fukushima power plants to cool down nine months
after the accident, RERF continues to provide
information and assistance in many forms to thecitizens of Japan and the rest of the world. The
A-bomb survivors of Hiroshima and Nagasaki
should be recognized for their enormous contributions to the ABCC and RERF’s search for knowledge and understanding of the risks of exposure toradiation. The results of those studies are now
being applied to serve decision-making and the citizens of the survivors’ own homeland, Japan, during this period of considerable uncertainty, misinformation, and misunderstanding. In this issue we
begin by providing a brief summary of RERF scientists’ responses, contributions, and involvement
as the planning for follow-up studies of thoseaffected in the Tohoku region of northern Japan
continues. A public lecture series reporting andexplaining the findings of RERF that was begun
last year in Hiroshima, has now been begun in
Nagasaki (see cover photo). The second of the public lectures was held in Hiroshima on December 10
and included “Thinking about low-dose radiation
exposure risk” and “Methods for radiation dose
assessment.” In Facts and Figures you will also geta sense of the many contacts that have been maderequesting information from RERF’s website.
The Fukushima accident has impacted RERF in
many ways. One side effect has been that several
distinguished scientists from around the world havevisited RERF as part of their consultative work inJapan, some of them for the first time. For example,
please read about the visit of Dr. Daud Mohamad,
Deputy Director General and Head of Nuclear

Sciences and Applications of the International
Atomic Energy Agency (IAEA) who was also
accompanied by Dr. Eduardo Rosenblatt, Head of
the Applied Radiation Biology and Radiotherapy
Section of the IAEA.
Please read about the first meeting of the Boardof Councilors (formerly the Board of Directors)
under the new guidelines required as RERF transitions to a public-interest incorporated foundation(PIIF). And finally, summaries of three recent
RERF research papers were selected for a numberof reasons. Two of the authors, Drs. Asao Noda andWaka Ohishi, were recently promoted to Assistant
Department Chiefs in their respective departments.
Dr. Noda is planning an international workshop in
January that will focus on the role of stem cellresearch in radiation carcinogenesis and in thisissue he describes an interesting model that he hasdeveloped in his laboratory. The papers of Dr.
Ohishi and Dr. Ikuno Takahashi represent examplesof the use of RERF’s clinical databases to study
risks of diseases associated with an aging population. Such studies were the focus of a visit by Dr.
Judith A. Salerno, Executive Officer of the Instituteof Medicine of the National Academies. Dr.
Salerno was formerly Deputy Director of the U.S.
National Institute on Aging (NIA) and she participated in a small workshop with RERF scientists todiscuss how RERF’s research might contribute to
the study of aging. Such research is important since
it improves our understanding of the backgroundrisks from “natural diseases” and thereby improves
the quality of our radiation risk estimates. The
knowledge gained also benefits the health of the
A-bomb survivors and medicine for all mankind—sounds very consistent with the mission of RERF
and the requirements of a PIIF too!
We hope that you enjoy this issue and don’t
hesitate to let us know how we might improve
our reporting of RERF’s many activities. Mataoidekudasai (goodbye and please come again),

Evan B. Douple
Editor-in-Chief

IAEA Deputy Director General Daud Mohamad (second
from right) and Dr. Eduardo Rosenblatt (right) being briefedby the directors and senior staff of RERF on November 22
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Yuko Ikawa
Technical Editor

RERF Update Volume 22, Issue 2, 2011

2

Letters to the Editors, RERF News

Letters to the Editors
As to the article on nursing in the years of
ABCC (RERF Update Volume 20, Issue 2, 2009), I
found it very interesting; however, there is one significant error. Chiye (Chiyoko) Watanabe was not
the second director of nursing. The head of nursing
after Louise Cavagnaro left would have been
Mildred Sherwood and she shared that function
with Marion Batchelder. In fact, these are two of
the “gaijin” women in the center of the front row of
the picture of the nurses that accompanied the article. In this same picture, Chiye Watanabe is thesecond person on the left in the front row. Chiye
was, at one time, in charge of the Genetics nurses.
She was an exceptionally fine woman. If memory
serves me correctly, Mildred and Marion bothcame to ABCC from Duke University, and I think it
was Grant Taylor who recruited them. You may
remember that he too had come from Duke where
he was Associate or Assistant Dean of the Duke
Medical School.

Warmest regards,
Jack Schull(former RERF Vice Chairman)
The recent issue of RERF Update was interesting with RERF’s involvement in the Tohoku disaster and Dr. Schull’s historical article.
Dr. Schull has experienced the transition of
ABCC and Hiroshima city from 1947 when he firstarrived to the present RERF and the modernizationof the city because of his involvement all theseyears. The readers undoubtedly are appreciative oflearning what had transpired in those years when
Japan was slowly recovering from the vast destruction.
Sincerely,
Merry Y. Uemoto(former secretary to Dr. William J. Schull)

Responses to the Fukushima Dai-ichi Nuclear Power Plant Crisis
Immediately after the nuclear power plant crisis
occurred on March 11, 2011, RERF convened its
Committee for Radiation Emergency Medical
Response (Chair: Chief Scientist Kazunori Kodama,Vice Chair: Information Technology Department
Chief Hiroaki Katayama) and has since adopted thefollowing measures based on deliberations led by
the relevant committee:

1. Dispatch of experts to affected regions andradiation measurement
a. Dispatch of a radiation technologist to Fukushima
prefecture for radiation measurement, March
16–22, 2011
Mr. Toshinori Kurisu, Assistant Chief of Technicians in the Department of Clinical Studies, wasdispatched to Fukushima prefecture as a memberof an emergency assistance team sponsored by theHiroshima International Council for Health Care of
the Radiation-exposed (HICARE). This team (sixmembers) was organized to respond to Fukushima
prefectural government’s request to the Hiroshima
prefectural government. In Fukushima, together
with the staff of local health and welfare offices andpublic health centers, the team members visited 12
evacuation sites, where they conducted radiation
measurements using radiation survey meters andprovided consultation services to the evacuees.
Return to Table of Contents

b. Dispatch of a research scientist and a radiation
technologist to Yamagata prefecture for providing
guidance and training regarding radiation measurement, March 17–24, 2011
Dr. Norio Takahashi, Research Scientist in
the Department of Genetics, and Mr. Katsuhisa
Yamasaki, Senior Technician in the Department ofClinical Studies in Nagasaki, were dispatched by
RERF at the request of the Yamagata prefectural
government via Japan’s Ministry of Health, Labourand Welfare. Dr. Takahashi and Mr. Yamasaki visited four public health centers and six evacuationsites in Yamagata prefecture, providing guidance
and training regarding radiation measurement
using radiation survey meters.
c. Radiation measurement at RERF Hiroshima
At the request of 33 persons (as of August 26)
who had moved to Hiroshima from areas near the
nuclear power plant, Dr. Asao Noda, AssistantChief, Department of Genetics, and other relevant
staff conducted radiation measurements of the individuals using radiation survey meters.

2. Information provision and consultation regarding radiation and healtha. Responses to inquiries from the general public
and media
Since March 11, the date of the start of the criRERF Update Volume 22, Issue 2, 2011

RERF Newssis, RERF has been inundated with general public
inquiries and media requests for information.
During the first three days (including Saturday
and Sunday) after the initial disaster, Chairman
Toshiteru Okubo received more than 50 telephoneinquiries regarding a wide variety of issues, notjust about research themes pursued by RERF.
Based on such inquiries, on March 14, the chairman prepared a list of the most frequently asked
questions, to which Dr. Nori Nakamura, Chief Scientist, provided model answers. Since that day, theresulting Q&A manuals have been shared among
all employees, while Dr. Nakamura has mainly
responded to inquiries from the media and the Public Relations and Publications Office to inquiries
from the general public. The Departments of Clinical Studies and Epidemiology have responded toinquiries from the Adult Health Study and the Life
Span Study subjects, respectively.
b. Creation of a special webpage
On March 15, on its website’s “What’s New”
page, RERF notified the general public of availability of brochures regarding radiation health effects.
On March 17, a special webpage related to the
nuclear power crisis was created, and thereafter
RERF website access dramatically increased (seeFacts and Figures).

3. Biological dose assessment
Dr. Yoshiaki Kodama, Chief of the Departmentof Genetics and member of the Chromosome Network Committee sponsored by the National Institute of Radiological Sciences, has been placed onstandby in case of occurrence of high-level radiation exposure, maintaining the emergency liaison
system within the network. Since chromosomebased dose assessment is time-consuming andlabor-intensive, and RERF is capable of conducting
such assessments for only an estimated 40–50
cases, it was decided that RERF would accept
requests only from the said network and theHiroshima University Radiation Emergency Medicine Promotion Center, a tertiary referral medical
institute for western Japan (to date no requests forbiological dose assessments have been received at
RERF).
4. Preparation for long-term epidemiologicalresearch
To prepare for the possibility of long-term epidemiological research on residents of the affectedareas, discussions on how to carry out suchresearch were initiated on March 15. Thereafter,with increased worldwide attention on the nuclear
power plant crisis, international organizations, governmental agencies, and research institutes might
be expected to turn to RERF’s history and experience in conducting long-term epidemiological
Return to Table of Contents

3
research.
With that in mind, RERF Chairman Okubo proposed to member institutions of the Council of
Radiation Effects Research Organizations on
March 29 establishment of a system for conducting
long-term epidemiological research. The Council
held an ad hoc meeting at the Fukushima Medical
University on April 2. On April 25, a group ofobservers from the Fukushima Medical University
visited RERF. On April 27, the sixth working meeting of the Council of Radiation Effects Research
Organizations was held in Tokyo, attended by Dr.
Okubo and Dr. K. Kodama. The Council decided tonominate advisors for radiation dose estimationand long-term epidemiological research fromamong the Council members.

5. Cooperation in a health management study
to be conducted by the Fukushima Medical
University
On May 13, a preparatory meeting for a committee to review Fukushima health studies washeld at the Fukushima Medical University, attended
by Dr. K. Kodama and Dr. Kotaro Ozasa, Chiefof the Department of Epidemiology. On May 20,
the Fukushima prefectural government called
on RERF to recommend a candidate to serve asa member of a review committee for the prefecture’s Health Management Study on Fukushima
Residents (hereinafter referred to as “Fukushima
Health Management Study”). In response, it was
decided that Dr. K. Kodama would assume theposition of committee member. On May 25 and
26, Professor Seiji Yasumura from the Fukushima
Medical University, as well as employees in charge
at the Fukushima prefectural government, visited
RERF and toured the Departments of Epidemiology and Clinical Studies. Subsequently, the visitors
exchanged opinions and held deliberations with
RERF staff members.
On May 27, the first meeting of the Fukushima
Health Management Study Review Committee washeld at the Fukushima Prefectural Jichi-Kaikan,
where the Fukushima prefectural government andthe Fukushima Medical University officiallyannounced that a health study of Fukushima residents would be conducted. On June 8, the firstmeeting in fiscal year 2011 of the Radiation Dose
Estimation Expert Panel was held at the Fukushima
Medical University, attended by Dr. Ozasa. On
June 12, the first meeting of the headquarters for
implementation of the Fukushima Health Management Study (FHMS) was held at the Fukushima
Medical University, attended by Dr. K. Kodama
and Dr. Ozasa. On June 18, the second meeting of
the FHMS Review Committee was held at the
Fukushima Prefectural Jichi-Kaikan, attended by
Dr. K. Kodama. At the relevant meeting it was
RERF Update Volume 22, Issue 2, 2011

RERF News
decided that a basic survey (questionnaire) would
be conducted to estimate radiation dose to which
Fukushima residents were exposed and that therelevant survey would be commenced around theend of June, starting with areas of relatively highcontamination.
On July 24, the third meeting of the FHMS
Review Committee was held at the Fukushima prefectural government offices, attended by Dr. K.
Kodama and Dr. Ozasa. At this meeting, discussions were held regarding implementation of thebasic study as well as more specific studies, including health examinations for those residing in theevacuation and other restricted areas and a thyroid
study for children. On August 12, RERF and the
Fukushima Medical University entered into a collaboration agreement in the fields of education,
research, and health (see RERF News). The fourth
meeting of the FHMS Review Committee was heldon October 17 in Fukushima and Dr. K. Kodama
attended. A summary of an international symposium (see below) was reported and the progress ofthe thyroid study was also discussed at the meeting.
With regard to the health management study targeting about two million Fukushima residents, RERF
will continue to provide know-how to the project,utilizing the foundation’s experience accumulated
through its follow-up of A-bomb survivors in
Hiroshima and Nagasaki.
Drs. Okubo and K. Kodama participated in theInternational Expert Symposium in Fukushima—
Radiation and Health Risks held in Fukushima on
September 11 and 12, 2011. Dr. Kiyohiko Mabuchi,
former chief of RERF’s Epidemiology Department
and currently Deputy Chief of the U.S. National
Cancer Institute’s Radiation Epidemiology Branchalso participated. The purpose of the symposium
was for a group of international and Japaneseexperts in radiation and health-related fields toreview the potential health effects of radiation fromthe Fukushima nuclear accident.
The symposium was also attended by experts
from relevant international, intergovernmental
bodies including the United Nations ScientificCommittee on the Effects of Atomic Radiation(UNSCEAR), the World Health Organization(WHO) and the International Atomic Energy
Agency (IAEA) and by representatives of nongovernmental organizations including the International Commission on Radiological Protection(ICRP). The symposium participants took note of
the wide global experience available for assessing
the consequences of major releases of radioactive
substances into the environment, which haveresulted from the international review of the aftermath of large accidents, such as the Chernobyl
accident. The conclusions and recommendations
that emerged from the symposium included the folReturn to Table of Contents

4lowing two that are especially relevant to RERF:(1) “Because of the long-term support to persons
exposed to radiation in Hiroshima and Nagasaki by
Japanese health professionals and scientists during
the past 60 years, Japan has considerable expertise,probably the best in the world, in radiation-related
issues. That expertise should be called upon to help
those affected by the Fukushima nuclear accident.
At the same time it is important to recognize theresponsibility of the authorities to learn as muchas possible from the information obtained.” and(2) “Health professionals and scientists must seek
to explain the possible effects or lack of detectable effects of radiation to the best of their ability
to the people of Fukushima and other concerned
individuals. Transparency in dose evaluation, risk
assessment and decision-making is vital. At thesame time, the scientific evidence and understanding must be provided to the public in a manner thatcan be readily understood.”
RERF’s Dr. Waka Ohishi (Assistant Chief of the
Department of Clinical Studies) has been consulted
by Fukushima Medical University regarding methodologies for storage of biological specimens at
RERF. They need the information to help themdevelop storage systems for the FHMS.

6. Advice to the government and other organizations
On April 1, Dr. K. Kodama, Chief Scientist, wasappointed as one of the policy investigators (sevenexperts with medical licenses) serving the Cabinet
Secretariat to provide advice regarding medical
responses to the Fukushima nuclear power plantcrisis. Thereafter, Dr. K. Kodama has engaged in
the relevant work two days each week.
In November, Dr. K. Kodama was also appointed
as an advisor to serve on the Advisory Committeeon Radiation and Health for Fukushima Prefecture.
During the same month, Dr. Roy E. Shore, Vice
Chairman, was appointed to serve as an advisor to
the Health Risk Assessment Working Group on the
Fukushima Dai-ichi Nuclear Power Plant Accident,
a working group of the WHO.

Mr. Toshinori Kurisu (right) measuring the soil contaminationin Fukushima prefecture as a sub-leader of the HICARE’sradiation-dose measurement team

RERF Update Volume 22, Issue 2, 2011

5

RERF NewsThe First Meeting of the Board of Councilors Held in Hiroshima
The first meeting of the Board of Councilors
was held at RERF’s Hiroshima Laboratory over thetwo days of June 21 and 22. The Board of Councilors, newly established with RERF’s status change
this April to an exceptional incorporated foundation with councilors, is a decision-making body
replacing the former Board of Directors. Of thetotal of eight Councilors, seven were in attendanceat the meeting, with representatives from the U.S.
and Japanese governments also present. The Councilors discussed RERF’s activities report, settlement of accounts report, activities plan, and working budget, as well as other agenda items such asprocedures for transition to a public-interest incorporated foundation (PIIF), RERF’s response to the
Fukushima Dai-ichi nuclear power plant crisis, andappointment of Directors.
In the meeting’s opening remarks, the representatives from the U.S. and Japanese governments
indicated that they would provide RERF with continued support. The main topics discussed at themeeting were the FY2010 activities report, settlement of accounts, and audit reports, with the settlement of accounts approved as drafted. The activities report touched on RERF’s responses to theongoing Fukushima Dai-ichi nuclear power plantcrisis, followed by Councilors’ comments callingfor RERF’s more active involvement in the situation.
The Councilors approved, as drafted, FY2011
plans for research activities including the clinicalstudy of A-bomb survivors’ children, research on
individual radiation doses, and collaborative projects with other organizations, as well as the

FY2011 working budget. Regarding the 12th planfor decreases in budgeted personnel slots, initiatedin FY2010, it was reported that the number of
employees would be reduced by five in the current
fiscal year.
A report concerning the 38th Scientific Council
meeting, at which detailed review of the Departments of Epidemiology and Statistics was conducted, outlined general recommendations callingfor improvement of research quality and development of research plans based on priorities that take
into consideration contemporary relevance andother factors, as well as five specific recommendations. Discussion about RERF’s responses to thoserecommendations then followed.
The ongoing procedures for transition to PIIF
status were explained, as follows: RERF obtained
the competent minister’s approval for change of its
Act of Endowment and transitioned to an exceptional incorporated foundation with councilors in
April of this year for an improved operational
structure toward becoming a PIIF; in addition to
the legally stipulated organizations, RERF also
explained its establishment of a Scientific Advisory
Committee and appointment of Local Advisors.
The Councilors approved a draft application for
status-change approval and a draft Articles ofIncorporation. It was then reported that RERF wasscheduled to submit the application to Japan’s
Cabinet Office and to complete transition to PIIF
status by April 2012.
Lastly, the Councilors appointed three Directors, two Scientific Advisors, and two Local Advisors.

Participants of the first meeting of the Board of Councilors (Hiroshima Laboratory)

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RERF Update Volume 22, Issue 2, 2011

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RERF News

Hiroshima and Nagasaki Local Liaison Council Meetings
The Hiroshima and Nagasaki Local Liaison
Councils, established to incorporate into RERF’s
operations local community input regarding maintenance of the health and improvement of the welfare of atomic-bomb survivors, consist of representatives of related local organizations, including
universities, medical institutions, A-bomb survivors’ organizations, prefectures, municipalities,
and other leaders in their field.
The 20th meeting of the Nagasaki Local Liaison
Council was held at the Nagasaki Laboratory on
July 14, 2011. Following greetings by Chairman
Toshiteru Okubo and Dr. Shigeru Katamine, President of Nagasaki University and chairman of theNagasaki Local Liaison Council, RERF reported
on its present status, recent research activities andresults, and its clinical study of second-generation
atomic-bomb survivors (F1 clinical study). The status of RERF’s collaborative study with the U.S.
National Institute of Allergy and Infectious Diseases (NIAID) and RERF’s public relations activities, including public lectures in Hiroshima andNagasaki, were also touched on. In response to theabovementioned presentations, the council members asked several questions, such as methods used
for assessment of internal radiation exposure,proper recognition of psychological and mental
effects of radiation exposure, and locating F1 clinical study participants who happen to change
addresses.
RERF also made a report concerning its responseto the Fukushima Dai-ichi nuclear power plant crisis to the effect that RERF, in collaboration withother institutions concerned, intends to strengthen
its support for and cooperation in long-term epidemiological studies in Fukushima. Council members
provided RERF with many valuable opinions about
RERF’s plan. The 20th meeting concluded with Dr.
Katamine’s closing remark that the council encour-ages RERF to fully review the opinions expressedat the meeting and incorporate them into its operations.
The Hiroshima Local Liaison Council heldits 17th meeting on July 27 at the Hiroshima
Laboratory. At the meeting chaired by the council chairman Dr. Toshimasa Asahara (Presidentof Hiroshima University), RERF made the same
reports that it did in Nagasaki and, as was the casefor the meeting in Nagasaki, the council members
expressed various opinions. In particular, a strong
request was made for relocation of the Hiroshima
facilities, as also happened at the last year’s
meeting. RERF’s report on its response to the
Fukushima Dai-ichi nuclear power plant crisis led
to active discussion concerning RERF’s support for
long-term epidemiological studies in Fukushima
and strengthening of collaborative arrangementswith other institutes. RERF reported that it had
agreed with Fukushima Medical University to sign
a collaborative agreement on education, research,and health care in order to allow RERF to use its
expertise and experience accumulated throughlong-term studies of atomic-bomb survivors inhealth surveys to be conducted among residents inthe affected area.

The 17th Hiroshima Local Liaison Council meetingFirst Public Lectures for Citizens Held in Nagasaki
As a result of the success of the first public lectures in Hiroshima, RERF sponsored its first public
lectures for citizens in Nagasaki at a hall of theNagasaki Atomic Bomb Museum from 1:30 to 4:00
in the afternoon of July 16 (see cover photo). The
open lecture program for citizens was planned topromote exchange between citizens and RERF
staff by providing readily understandable explanations to the general public including A-bomb surviReturn to Table of Contents

vors on research achievements concerning healtheffects of A-bomb radiation obtained at RERF overmany years. More than 180 people attended.
The public lecture program consisted of two
lectures. First, Chief Scientist Kazunori Kodama
spoke on “Radiation and cancer risk,” explaining
how much increase in risk of cancer, including leukemia, has been observed due to radiation exposure, based on results of long-term health effects
RERF Update Volume 22, Issue 2, 2011

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RERF News
studies. Next, Chief Scientist Nori Nakamura gave
a lecture titled “Studies on children of A-bomb survivors conducted thus far,” introducing research
results involving such topics as birth abnormalities,
chromosome aberrations, mortality, cancer incidence, and the absence of detected effects in children who were born to parents who had been
exposed to A-bomb radiation.
At the beginning of the program, following
greetings by Chairman Toshiteru Okubo, Dr. Yuji
Nagayama, Director of the Nagasaki University
Atomic Bomb Disease Institute, read a message
from Dr. Shun-ichi Yamashita (former Dean of theNagasaki University Graduate School of Biomedical Sciences), who had assumed the position ofVice President of Fukushima Medical University
on the previous day. Before a question-and-answer
session, Dr. Masao Tomonaga, Director of theJapanese Red Cross Nagasaki Atomic Bomb Hospital, made special remarks about the relationshipbetween Nagasaki and RERF. In this question-andanswer session, many questions were raised,
including those about internal and external exposure caused by nuclear power plant accidents. Even
after the program ended, some citizens remained in
the hall eagerly asking questions.

Open House Events in Hiroshima and Nagasaki
August 5 and 6 and August 8 and 9, RERF
held its annual Open House in Hiroshima (17thannual event) and Nagasaki (15th annual event),
respectively, under the theme “Radiation and healthsciences.” With enhanced public interest in radiation due to the Tokyo Electric Power Company’s
Fukushima Dai-ichi nuclear power plant crisis,
the events this year featured a special exhibition
introducing the basics of radiation and its effects onhuman health, in addition to the regular exhibitionsof our latest research results.
At the Hiroshima Laboratory, a specialist’s corner set up next to the abovementioned special
exhibition corner, attracted many visitors eager to
ask questions, including families with children. In
the event’s public lectures, which have become partof the regular program in Hiroshima, Dr. Asao
Noda, Assistant Chief of the Department of Genetics, and Chief Scientist Nori Nakamura spoke
about “What is radiation?” on the 5th and 6th,
respectively, and on the 6th, Dr. Kotaro Ozasa,
Chief of the Department of Epidemiology, spokeon the theme “What is radiation epidemiology?”
Compared with the two lectures of last year’s

event, this year’s Open House had three lecturesattended by large enthusiastic audiences who asked
many questions even after the lectures were concluded. The Hiroshima Laboratory’s Open Housedrew 1,375 visitors for the two days.
The Nagasaki Laboratory also prepared special
exhibition posters introducing the basics of radiation science. Information about the efforts of RERF
employees who were dispatched to Fukushima
prefecture to assist in that prefecture’s responseto radiation exposure, such as radiation measurement and screening, and to Yamagata prefecture
to help people evacuated from Fukushima to
Yamagata, was also introduced. The special exhibition attracted many visitors, including families
with children, who listened intently to explanations
provided by researchers in front of the posters
illustrating basic information about radiation andits human health effects. Despite occasional heavy
rain on both days of the event, all of the handson exhibitions attracted many visitors as usual.
Nagasaki Laboratory’s Open House drew 390 visitors for the two days.

Q & A corner in the Hiroshima Open House

Open House at the Nagasaki Laboratory

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RERF Update Volume 22, Issue 2, 2011

8

RERF NewsRERF and Fukushima Medical University Sign
a Collaborative Agreement
RERF and Fukushima Medical University, inthe wake of the nuclear crisis at the Tokyo ElectricPower Company’s Fukushima Dai-ichi nuclear
power plant, agreed to strengthen their collaborative relationship in the fields of education, research,and public health, signing a collaborative agreement at the university on August 12, 2011.
The agreement aims at further development ofboth organizations and establishment of a pioneering educational/research center concerning healtheffects of radiation through promotion of educational and academic research activities in the fieldof radiation effects research, closer interactions
between university faculty members and RERF
researchers, and improvement of the health andwelfare of residents of Hiroshima, Nagasaki, andFukushima prefectures.
In addition, aside from health effects of direct
A-bomb radiation exposure, which RERF has
investigated on its own over many years, progressis expected in research on health effects of internal
exposure to low-dose radiation and lifetime cumulative exposure, the types of radiation exposuresfrom the radioactive contamination emitted in the

Fukushima catastrophe and currently causing public concern.
On the same day, Fukushima Medical University also signed a collaborative agreement with the
National Institute of Radiological Sciences.

(from left) Dr. Yoshiharu Yonekura, President, National Institute of Radiological Sciences, Dr. Shin-ichi Kikuchi, President, Fukushima Medical University, and RERF Chairman
Toshiteru Okubo

IAEA’s Deputy Director General and Other Officers Visit RERF
RERF received visits from four officers of theInternational Atomic Energy Agency (IAEA) during the period from August through November,2011. On August 5 and September 15, Dr. Rethy
Chhem, Director of Division of Human Health,
Department of Nuclear Sciences and Applications,and Dr. Jan Wondergem, Applied Radiation Biology and Radiotherapy Section, visited RERF’s
Hiroshima Laboratory, respectively. On November
22, Dr. Daud Mohamad, Deputy Director Generaland Head of Department of Nuclear Sciences andApplications, visited RERF, with Dr. Eduardo
Rosenblatt, Head of the Applied Radiation Biology
and Radiotherapy Section, Department of Nuclear
Sciences and Applications.
Dr. Rethy Chhem, who visited during our OpenHouse event, was in Hiroshima to exchange opinions on research collaboration with the Hiroshima
International Council for Health Care of the Radiation-exposed (HICARE). He was guided by RERF
Chairman Toshiteru Okubo on a tour of RERF’s
posters on the foundation’s history, chromosomalchanges caused by radiation, dosimetry systems
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used for the A-bomb survivors, collaborations
between IAEA and RERF, and a summary of theactivities of HICARE. Later in the Chairman’s
Office, Vice Chairman Roy E. Shore explained
RERF’s recent research results to Dr. Chhem, leading to an active exchange of questions and answers.

(from left) Dr. Rethy Chhem of IAEA, RERF Chairman
Toshiteru Okubo, Statistics Department Chief Harry Cullings,
and Vice Chairman Roy Shore

RERF Update Volume 22, Issue 2, 2011

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RERF News
Dr. Wondergem is an expert in the field of biodosimetry based on chromosomal aberrations andplays a core role in research collaboration between
the IAEA and HICARE. After being greeted by thechairman and senior staff, he toured the facilities,
including the biological specimen storage facilities,
led by Chief Scientist Kazunori Kodama. Dr.
Wondergem subsequently had a substantive discussion regarding collaborative research programswith the chiefs and assistant chiefs of the Departments of Genetics and Radiobiology/Molecular
Epidemiology.
IAEA Deputy Director General Mohamad and
Dr. Rosenblatt, who visited RERF in November,were briefed on RERF’s current status, futureplans, and research activities by Chairman Okubo
and Vice Chairman Shore. They were guided
by the chairman and other senior staff on a tourof the facilities, including the Departments ofGenetics and Epidemiology. Drs. Mohamad andRosenblatt visited RERF on the occasion of being
in Hiroshima to attend the 2011 HICARE International Symposium “The Effects of Radiation on the

IAEA Deputy Director General Daud Mohamad (second
from right) and Dr. Eduardo Rosenblatt (background left)
with RERF Chairman Toshiteru Okubo (right) as they depart
RERF

Human Body—Toward Establishing an International Network for Medical Care for the Radiationexposed,” held on November 23 in cooperation
with IAEA, where they gave keynote speeches
and Dr. Mohamad served as a commentator in the
symposium.

Ambassador Mari Amano, Delegation of Japan to theConference on Disarmament, Visits RERF
Ambassador Mari Amano, from the Delegationof Japan to the Conference on Disarmament, visited the Hiroshima Laboratory on September 16.
The Delegation is an organ that deals with the Conference on Disarmament held in Geneva, the First
Committee of the United Nations General Assembly held in New York, and other international disarmament meetings held around the world, thereby
advancing Japan’s disarmament diplomacy.
Mr. Amano toured the RERF facilities after
being briefed on the organization’s current status
and research activities by Chairman Toshiteru
Okubo and other officers. Mr. Amano, who was
appointed to the position of Japan’s ambassador to
the Conference on Disarmament on September 1,
2011, came to Hiroshima for the purpose of making a courtesy visit to the mayor of Hiroshima. He
visited RERF to gain a general understanding of
RERF’s research studies.

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Ambassador Mari Amano, from the Delegation of Japan to
the Conference on Disarmament (far left) being briefed by
the directors and senior staff of RERF

RERF Update Volume 22, Issue 2, 2011

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RERF News

Staff News
Midori Soda, Assistant Chief in the Department of Epidemiology, Nagasaki, and Mieko
Kodaira, Laboratory Chief of Biochemical Genetics, Department of Genetics, reached mandatory
retirement age on December 31, 2010 and June 30,
2011, respectively. Dr. Soda was re-employed asa Research Scientist in the same department as ofJanuary 1, 2011 and Dr. Kodaira was re-appointed
as Laboratory Chief as of July 1.
In the Laboratory of Cytogenetics, Departmentof Genetics, Laboratory Chief Asao Noda was promoted to Assistant Department Chief, and Yuko
Hirai, Senior Scientist, was promoted to Laboratory Chief to replace the former laboratory chief

Noda on July 1. In the Department of ClinicalStudies, Waka Ohishi, Division Chief of ClinicalLaboratories, was promoted to Assistant Department Chief effective from August 1.
Ravindra Khattree resigned effective August
15 as a Senior Scientist in the Department of Statistics. He returned to the U.S. where he is a Professor
in the Department of Mathematics and Statistics at
Oakland University in Rochester, Michigan. As of
November 1, Norio Takahashi, Research Scientist,
transferred to the Department of Radiobiology/
Molecular Epidemiology from the Laboratory ofBiochemical Genetics in the Department of Genetics.

Visiting Student Researchers
Sandra Jaudzema, MD
I am a trainee (from June 1 to July 28, 2011) in
the field of pathology from Latvia. Latvia is a small
but very beautiful country on the sandy coasts of
the Baltic Sea with its wonderful capital Riga. My
country is rich in beautiful nature and various culture traditions—especially singing.
I graduated from the University of Latvia Faculty of Medicine in 2010. Currently I am studying
at the Department of Continuing Education in Riga
Stradins University and working at Pauls Stradins
Clinical University Hospital’s Institute of Pathology. Work at the hospital is one of my trainee
duties. Additionally I also work as a lecturer at the
Department of Pathology in Riga Stradins University Faculty of Medicine.
It was a great opportunity for me to study andwork in the Radiation Effects Research Foundation(RERF) and the experience was very important for
my education and my development of professional
skills. In RERF’s Immunology Laboratory, I wastrained in the effects of radiation exposure on
immune function, especially using methods tomeasure intracellular reactive oxygen species levels in plasma samples, to prepare lymphocyte cellsubsets, and to examine genomic instability. I amvery grateful for this chance and would like toexpress my gratitude to the Hiroshima International
Council for Health Care of the Radiation-exposed(HICARE) and RERF for the opportunity to participate in the RERF Training Program. I would
also like to express my deepest gratitude to the staffof the Department of Radiobiology/Molecular Epidemiology for their great support and warm-heartedness, especially to Dr. Tomonori Hayashi who
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Sandra Jaudzema, MD (right) with Dr. Tomonori Hayashi at
the Immunology Laboratory

guided and supervised me through this delicate
world of science.
Luzhou Xu, MD, PhD
I am a physician at the affiliated hospital of
Nanjing University of Traditional Chinese Medicine (TCM) in Nanjing, China, and I also received
my PhD there. Our hospital is one of the national
clinical research centers. Although I did some clinical and basic research work in the last five years,
I am aware of my insufficiencies and I need morelaboratory training to further my scientific career.
I arrived at Hiroshima University in early June
2011, and then came to the Genetics Department of
RERF. I am honored to have been accepted as avisiting research fellow here.
At the guidance of Dr. Asao Noda, I joined his
team and focused on the mechanisms of DNA douRERF Update Volume 22, Issue 2, 2011

11

RERF Newsble-strand break repair following ionizing radiation. I likethis challenge because it isentirely different from my former work in China. I used toread Chinese publications but
now I’m reading the international top journals such as
Luzhou Xu, MD, PhD Nature, Science, and Cell, andperforming some gene-manipulation experiments. I changed my idea for researchfrom pathophysiology to cell signaling. I’m interested in whether Chinese herbs have something to
do with the repair mechanisms of double-strand
breaks or recovery from radiation injury. I am
expecting to get good results.
In RERF, I enjoy working with such diligent
scientists. We are able to exchange our ideas, discuss
our outcomes, and remark about our conclusions. I
thank RERF’s amicable and unselfish scientists andstaff who have been so helpful. I think my days in
RERF will be an important memory in my life.
Ayako Takamori
I am a doctoral student in
the biostatistics program at
Kurume University’s Graduate
School of Medicine, and I am
here at RERF as a visiting student fellow in the Departmentof Epidemiology. Immediately
after I was born in Hiroshima,
Ayako Takamori
my parents moved my family to Tokyo, then to Ehime
prefecture, and finally back to Hiroshima. Whenin Ehime, I attended Matsuyama Higashi HighSchool, where Natsume Soseki, a famous Japanesewriter, once taught (located near Dogo Onsen Spa).
I have had a strong interest in researching social
medicine ever since I was young. While I was tak-ing general education classes during my master’s
program at Kyushu University’s Graduate Schoolof Medical Sciences, in which I enrolled to study
medical care systems assessment, I encountered thefield of statistics. Just as I was worried about everfinding an opportunity to study statistics further, I
came to know of the Kurume University Biostatistics Center. When I learned that Kurume University
had a partnership agreement with RERF, I decided
to enter the Center’s program hoping to become
involved in research of the health effects of the
A-bomb survivors, an area of study in which I havealways wanted to take part. Since then I have beenworking diligently to enhance my knowledge of
medical statistics based on mathematical statistics.
With this internship opportunity, I was able to add
even more motivation to research and develop a
research protocol titled “Mortality analysis of theLife Span Study (LSS) cohort taking into accountmultiple causes of death indicated in death certificates” in June 2011. The objective of the project is
to study association between radiation and underlying/secondary (other than underlying) causes ofdeath that were identified from those indicated in
the death certificates of A-bomb survivors who had
been registered as LSS subjects.
At RERF, research scientists and administrative
staff have been so kind to me for which I am very
grateful. Although I am shy and easily become nervous around strangers, the friendliness of people at
RERF makes me relaxed, and as days go by, it iseasier for me to talk to people, which has become
one of my pleasures at RERF. I am grateful for the
instructions I receive at RERF in terms of English
and practical study methods. During the course ofthis fiscal year, I will travel back and forth between
Kurume and Hiroshima to make progress on mystudy. I am firmly determined to work hard to complete my analysis and write a paper as soon as possible. Thank you very much.

Recognition Received by an RERF Scientist
Dr. Waka Ohishi, Assistant Chief, Departmentof Clinical Studies, was recognized recently by
the Editor-in-Chief of the journal of the American
Association for Cancer Research, Cancer Epidemiology, Biomarkers and Prevention (CEBP). In his
letter to Dr. Ohishi, CEBP Editor-in-Chief Timothy
A. Rebbeck said:“Congratulations! Your article ‘Risk factors forhepatocellular carcinoma in a Japanese population:
A nested case-control study’ is one of the mostcited 2008 CEBP articles from Japan. We appreciate your excellent contribution to our journal andReturn to Table of Contents

hope you will consider Cancer Epidemiology, Biomarkers
and Prevention for your future
manuscripts.”
Recently, Dr. Ohishi waspromoted to Assistant Chief inthe Department of ClinicalStudies (see Staff News). A
2011 follow-up paper to her Waka Ohishi, MD,
2008 paper is summarized by PhD
Dr. Ohishi in this current issueof RERF Update (see Science Articles).
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Conference and Workshop Reports

The 52nd meeting of the Late A-bomb Effects Research Association
Kanya Hamasaki, Research Scientist
Laboratory of Cytogenetics, Department of Genetics
The 52nd meeting of the Late A-bomb Effects
Research Association was held on June 5, 2011 at
the hotel Hacchobori Chanter. The opening address
by Dr. Saeko Fujiwara, Chief of the RERF Department of Clinical Studies, Hiroshima, and thisyear’s meeting organizer, marked the beginning of
the meeting program consisting of two special lectures, one symposium, and 29 general presentations.
In the first of the special lectures, titled “Utilization of HICARE’s (Hiroshima International
Council for Health Care of the Radiation-exposed)
expertise in the follow-ups of Hiroshima, Nagasaki,
Chernobyl, the nuclear fuel processing company
JCO accident, and the Fukushima nuclear power
plant crisis,” Dr. Hiroo Dohy, Director of theHiroshima Red Cross Hospital and Atomic-bomb
Survivors Hospital, talked about the atomic bombings, several radiation accidents, and HICARE’shistory. He said that a long-term health survey
needs to be conducted for the victims of radiation
contamination in the Fukushima nuclear power
plant crisis and that it is desirable for follow-ups tobe based on HICARE’s framework. In the second
special lecture, Dr. Koichi Tanigawa, Professor at
the Emergency and Critical Care Medicine, Graduate School of Biomedical Sciences, Hiroshima
University, gave a lecture titled “Lessons from the
Fukushima nuclear power plant disaster: Present
status and challenges of Japan’s emergency medical care system.” Dr. Tanigawa, who reestablishedthe radiation emergency medical response systemthat had become dysfunctional in the affected areas
after the crisis, laid out some of the problems identified in the crisis, such as dysfunctional chain ofcommand in the national government, insufficient
information on radiation, incomplete systems for
medical care of the radiation-exposed, and underestimation of the importance of radiology in medical school education.
Those lectures were followed by a symposiumon the theme “Global dissemination of results fromresearch on late effects of radiation.” Dr. Kenji
Kamiya, Director of the Hiroshima University
Research Institute for Radiation Biology and Medicine (RIRBM), Dr. Shun-ichi Yamashita, Dean of
the Nagasaki University Graduate School of Biomedical Sciences, and Mr. Takanobu Teramoto,
RERF Executive Director, talked about global dissemination of results from research on late effectsof radiation and scientific information at their
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respective institutes. Dr. Satoru Ubuki, a former
RIRBM researcher, spoke about Hiroshima’s history of information communication relating to thedamage caused by the atomic bombing. In addition
to those four symposiasts, two speakers gave designated remarks: Mr. Masaya Yamauchi, assistantchief editorial writer at the Chugoku Shimbun,
spoke on the topic of radiation risks from the
Fukushima and Chernobyl nuclear accidents fromthe viewpoint of a news reporter; and Mr. Koichiro
Maeda, Director of the Hiroshima Peace Memorial
Museum, talked about the present status of themuseum’s displays and renewal plans.
The 29 general presentations were all delivered
orally, and included 13 related to clinical or epidemiological studies of the atomic bombings ofHiroshima and Nagasaki, 12 related to basic
research into radiation exposure based on animal orcell experiments, and four related to radiation contamination from the Fukushima nuclear power
plant crisis. Representing RERF, Mr. Katsuhisa
Yamasaki, Senior Technician of the Department ofClinical Studies, Nagasaki, who visited Yamagata
prefecture with Dr. Norio Takahashi (Research Scientist, Department of Genetics), made a presentation titled “Support for people evacuated to
Yamagata prefecture due to the nuclear power plantcrisis.” Dr. Yoshiki Tanakamaru, Chief of the
Nuclear Scanning Section, Central Radiology Division, Department of Radiology, Hiroshima Red
Cross Hospital and Atomic-bomb Survivors Hospital, who led the team dispatched by HICARE to
Fukushima, which Mr. Toshinori Kurisu (AssistantChief of Technicians, Department of Clinical Studies, Hiroshima) also joined, made a presentation
titled “HICARE assistance in the Fukushima

RERF’s Mr. Katsuhisa Yamasaki speaking about his
activities in Yamagata prefecture in March 2011

RERF Update Volume 22, Issue 2, 2011

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Conference and Workshop Reports
nuclear power plant crisis.”
The top concern at this meeting was the
Fukushima nuclear power plant crisis, which had
spiraled out of control immediately after the Great
East Japan Earthquake on March 11 and still has
not come to an end. The crisis was discussed inboth of the two special lectures and referred to in
the symposium and some of the general presentations, reminding the audience of the magnitude of
the radioactive contamination from the Fukushimacrisis. I also felt the motivation of the participantsof this meeting to use the experience and expertise
accumulated in Hiroshima and Nagasaki to help
Fukushima in various areas, including mitigationof damage caused by harmful rumors and followup health surveys of its residents. RERF surely willplay a major role and bear great responsibility insuch support efforts. This meeting encouraged mydesire to be of help to such efforts in some fashion.

The Second Epidemiological Training Workshop for Biologists
Nori Nakamura, Chief Scientist
On September 26–27, 2011, the Epidemiological Training Workshop for Biologists, hosted
by the Council of Radiation Effects Research
Organizations, was held at the RERF Auditorium
in Hiroshima. This year’s event turned out to bea lively gathering, attracting over 80 scientists(56 non-RERF and 26 RERF participants). (TheCouncil of Radiation Effects Research Organizations, consisting of Fukushima Medical University,
Hiroshima University, the Institute for Environmental Sciences, Nagasaki University, the National
Institute of Radiological Sciences, the Radiation
Biology Center [Kyoto University], and RERF [inalphabetical order], was established to facilitate
mutual understanding and collaboration amongradiation effects research organizations.)
On the first day of the workshop, RERF Chairman Toshiteru Okubo gave opening remarks, andthe participants introduced themselves. Dr. Ritsu
Sakata, Department of Epidemiology, then delivered lectures titled “Overview of epidemiologicalstudies (including explanation of terms)” and “Calculation of low-dose risks (practical training).” Following those lectures, Dr. Kotaro Ozasa, Chief ofthe Department of Epidemiology, and Mr. Eric
Grant, from the same department, spoke on thetheme “Low-dose risks are difficult,” with Dr.
Nori Nakamura, Chief Scientist, and Dr. Yukiko
Shimizu, Department of Epidemiology, then discussing “Breast cancer risk and childhood susceptibility (age dependence).” In the afternoon, Professor Michiaki Kai, Oita University of Nursing and
Health Sciences, and Professor Emeritus Ohtsura
Niwa, Kyoto University, gave talks titled “Childhood susceptibility of thyroid cancer” and “Agesusceptibility from the viewpoint of biologicalmechanisms,” respectively, with a general discussion held under the theme “What is radiation biolReturn to Table of Contents

ogy’s aim?” The second day’s lectures were titled“Fetal radiation susceptibility” (delivered by Chief
Scientist Nori Nakamura and Dr. Hiromi Sugiyama,
Department of Epidemiology), “Childhood susceptibility to leukemia” (by Dr. Nori Nakamura) and“Genetic radiation effects” (by Dr. Nori Nakamura).
Due to the situation at the Fukushima Dai-ichi
nuclear power plant caused by the earthquake thatstruck the Tohoku region in March, participants
engaged in active questions and answers with astrong interest in that particular issue. A specificquestion regarding how to respond to questions of
the kind that were actually asked in Fukushima wasraised. Some lectures included many abbreviations
that not everyone could understand, forgetful of thefact that the workshop was intended for communication across different fields of research. However,many participants are seeking just this kind ofworkshop for learning and interaction, and thus for
us to continue to offer such opportunities is deemed
important.
The discussion went around in circles at one

Participants of the second epidemiological training workshop
for biologists

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Conference and Workshop Reports
point due to lack of accurate understanding of relative risk, absolute risk and lifetime risk, but theparticipants ultimately seemed to gain a goodunderstanding overall. In response to a request by
the epidemiologists, we would very much like toplan a biological training workshop for epidemiol-ogists, which RERF staff members alone should be
able to organize easily. Our future challenge seems
to be the creation of common research themes,
shared between RERF scientists and outside
researchers, on the occasion of such gatherings.

The 14th International Congress of Radiation Research—A Meetingof Science and History
Evan B. Douple, Associate Chief of Research
The largest meeting of radiation scientists in theworld is typically the International Congress ofRadiation Research (ICRR) which is held approximately every four years. The 14th ICRR was held
for the first time in Warsaw, Poland, from August
28 to September 1, 2011. It was very fitting that themeeting was hosted by the Maria SkłodowskaCurie Polish Radiation Research Society, since themeeting celebrated the 100th anniversary of theNobel Prize awarded to Maria Skłodowska-Curie
for the separation and characterization of radiumand polonium. That was the second time for the
famous scientist who was born in Warsaw toreceive the award—in 1903 she was awarded theNobel Prize for Physics along with her husband
Pierre and Henri Becquerel. Some readers may
have forgotten that less than a year and a half afterMarie Curie’s death (which was from leukemia
presumably caused by many years of work withradioactive substances, initially without protective
measures), her daughter and son-in-law received
the Nobel Prize for the discovery of artificial radiation, increasing the number of Nobel Laureates in
one family to four! Her granddaughter presented alecture at the meeting.
The lectures and poster sessions were held in the
Palace of Culture and Science, which is the highest
building in Poland (42 stories, 231 m). Completed
in 1955, it was a gift of the Stalinist Soviet Union
to the Polish People’s Republic. The seven scientists who attended the meeting from RERF werequite impressed by the massive building, but foundit quite difficult to get oriented and to find one’s
way around a building which has 3,288 rooms andhalls! A well-attended congress plenary lecture wasan update on the Fukushima Dai-ichi nuclear
power plant disaster by Takeo Ohnishi from the
Nara Medical University School of Medicine inJapan. A total of four scientific posters were
defended by RERF’s Harry Cullings, Kanya
Hamasaki, Wan-Ling Hsu, and Ritsu Sakata. In
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addition, Kazunori Kodama presented an “Eyeopener” invited lecture “Update on radiation risk
estimates from A-bomb survivors,” Kotaro Ozasa
participated in a symposium on biological effectsof low doses where he presented an invited lecture
on “Radiation risk of cancer and noncancer mortality in atomic-bomb survivors, 1950–2003,” andEvan Douple participated in a symposium titled“The use of archiving data and biological materials—Examples and strategies,” where he presented
an invited lecture “The use of unique archived data
and biological samples by the Radiation Effects
Research Foundation.” The large congress provided an excellent opportunity to attend many
informative lectures, to promote RERF’s latest
work and findings, and to meet and exchange information with scientists from many countries.
The long trip home for some of the RERF scientists became longer when they were delayed fortwo days in Helsinki, Finland, because a typhoon
was causing flights to be cancelled in Japan. Theirjourney should be much shorter in four years whenthe 15th ICRR returns to Kyoto, Japan, where
RERF Board of Councilors member, Ohtsura

Dr. Harry Cullings (left) makes a point at his poster with an
ICRR participant

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Conference and Workshop Reports
Niwa, who was also the 2011 President of theCouncil of the International Association for Radia-

tion Research, will play a key role in organizing
this important event.

Visit to RERF by Dr. Salerno of the National Academies
Evan B. Douple, Associate Chief of Research
On September 14, Dr. Judith A. Salerno, theExecutive Officer of the Institute of Medicine(IOM) of the National Academies, visited RERF
and participated in a workshop related to the
RERF studies associated with aging. Dr. Salerno
is the executive director and chief operating officer of the IOM and is responsible for managing
the IOM’s research programs and guiding theirwork on a daily basis. Prior to coming to the IOM,
Dr. Salerno was Deputy Director of the National
Institute on Aging (NIA) at the National Institutesof Health, U.S. Department of Health and Human
Services. She oversaw aging research conducted
and supported annually by the NIA, including
research on Alzheimer’s and other neurodegenerative diseases, frailty and function in late life, andthe social, behavioral and demographic aspects ofaging. As the NIA’s senior geriatrician, Dr. Salerno
was vitally interested in improving the health andwell-being of older persons, and designed awardwinning programs to communicate health andresearch advances to the public. She was accompanied in her visit by Dr. Warren R. Muir, the Executive Director of the National Academies’ Divisionof Earth and Life Studies, which is the division
responsible for supporting RERF using funds
from an award from the Department of Energy.
Dr. Salerno visited RERF to learn about RERF’s
research and to provide advice regarding how the
research might be of even greater benefit to the
problems facing the world’s aged populations.
The workshop began with an overview of RERF
research by Vice Chairman Dr. Roy E. Shore,
including historical background, origin and composition of the major cohorts, and a description of thetypes of research conducted by RERF’s departments and working groups. An overview of pastand current RERF aging research in the ClinicalStudies Department was presented by Department
Chief Dr. Saeko Fujiwara. The studies using longitudinal Adult Health Study (AHS) data included
changes in typical clinical measurements (cholesterol, blood pressure, Hb, and white blood cells),
predictors of mortality (biological scores and handgrip), and specific diseases such as stroke (risk factors and lifetime risk). In addition, there have been
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studies of osteoporosis, dementia, predictors offunctional decline, and other aging studies. She
described the valuable and extensive laboratory
data that has resulted from the physiological tests
conducted by the biennial AHS examinations. Lifestyle and medical history data are available on
smoking, alcohol consumption, gynecological history, physical activity, diet, and education. Some
examples of special studies related to aging included
measurement of grip strength, auditory acuity,
vibration perception, skin elasticity, and reaction
time. Ongoing studies include the development ofpredictive measures for disability in a national collaborative study, a comparison of body composition (percent fat and percent lean body mass)
between AHS participants and a U.S. population(in collaboration with Dr. T. Harris, at the U.S.
NIA), and a study of physiological and serum
markers for cardiovascular disease or atherosclerosis. All of those studies have both a radiation andan aging component.
Dr. Michiko Yamada continued the workshop
by describing the AHS longitudinal data analyses,
especially focusing on aging-related disease morbidity, cognitive function and dementia. She
emphasized that the large scale of the AHS, theinclusion of both sexes with a broad range of ages,
and the long follow-up period allow unique assessment of morbidity of noncancer diseases and trends
in measurements with age. Future analyses will
include endpoints such as hypertension, diabetes
mellitus, hyperlipidemia, hyperuricemia, hypothyroidism, and osteo-arthritis. She then turned her
attention to dementia, pointing out that RERF has
published manuscripts regarding prevalence andincidence of dementia. In responding to questions
from Dr. Salerno, Dr. Yamada explained the diagnostic criteria that have been used in the dementia
studies and RERF’s involvement in the Ni-Hon-Sea
collaborative study of dementia using standardized
procedures to compare Japanese-Americans living
in Seattle and Honolulu with Japanese (Nippon)
living in Hiroshima (the AHS cohort). New researchstudies were begun in 2011 of the A-bomb survivors exposed prenatally or in childhood to assesslongitudinal declines in neurocognitive abilities
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Conference and Workshop Reports
related to aging and radiation.
Dr. Masazumi Akahoshi, Chief of the ClinicalStudies Department in Nagasaki, described resultsof studies relating aging processes, menopause,
diabetes mellitus, and subclinical hypothyroidism.
Additional studies have been conducted relating
trends in systolic blood pressure and body massindex. He described future study plans, such asmeasuring body weight fluctuations and agingrelated diseases, searching for biomarker differences between obese subjects who do develop diabetes and those who do not, and additional studies
of subclinical hypothyroidism and chronic kidneydisease.
The workshop then turned to a discussion of thecurrent and potential future aging-related studies
using stored biosamples. Dr. Waka Ohishi, Assistant Chief of the Clinical Studies Department,
Hiroshima, reviewed the varieties and numbers ofbiosamples whose collection began in 1969 andcontinues until today based on the AHS or the F1clinical cohort, including studies of the role of hormones in breast cancer, the role of Helicobacter
pylori in gastric cancer, and the roles of hepatitis
viruses in hepatocellular carcinoma. She stressedthat the potential future of RERF’s aging-related
studies using stored biosamples includes clinicalepidemiologic, immunologic, and genomic studies
which may lead to new insights regarding susceptibility to both radiation-induced and aging diseases.
The final session of the discussions with Dr.
Salerno included basic science presentations fromthe Department of Radiobiology/Molecular Epidemiology (RME). Department Chief Dr. Yoichiro
Kusunoki presented an overview of the current
studies of immunosenescence in RME and describeda large collaborative project that is continuing tostudy the effects of both aging and radiation thathave been found in the A-bomb survivors. Two
major areas of proposed future studies include epigenetic studies of radiation and aging in blood cell
subpopulations such as hematopoietic stem cells,
dendritic cells, granulocytes, and naïve T cells, andaging-related histological and molecular alterations
using autopsy noncancer tissues from the Life Span
Study (LSS). Dr. Kengo Yoshida discussed potential studies of the decrease in the diversity of T
cells and the exhaustion of effector and memory T
cells, two hallmarks of immunosenescence, and of
epigenomic analyses of memory T-cell populations. The studies should improve our understanding of the role of the changes associated with aging
and their resulting impact on cancer and susceptibility to other diseases. Dr. Yasuharu Niwa
described RERF’s study of the radiation effects on
aging-related epigenetic changes in various blood

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16cell subsets and of the role of epigenetic changes inaging-related disease among A-bomb survivors.
Future studies are planned to explore aging-related
epigenetic alterations that may be affected bypast radiation exposure, including DNA methylation status of selected genes, genome-wide DNA
methylation and histone methylation and acetylation. Also of interest are aging-related mitochondrial dysfunctions in autopsy cardiomyocyte specimens related to methylation and gene expression.
Dr. Reiko Ito described morphological studies on
aging using noncancerous tissues from autopsy
samples, such as evaluation of glomerulus number
and morphologic changes in the kidney, degeneration of the dermis, and atrophy in the digestive
tract. Dr. Masataka Taga described studies ofradiation effects on noncancer lung tissues among
A-bomb survivors with a focus on their roles incarcinogenesis. Since radiation exposure at older
ages confers greater lung cancer risk than it does atyounger ages, aging-related molecular alterations
in lung tissue are of particular interest
Dr. Salerno was impressed with our “incredible
information, databases and biosample resources.”
She encouraged RERF scientists to consider the
many opportunities for research projects and to
consider collaborative studies and objectives thatcan be considered across studies, disciplines, andinstitutions. For example, she indicated that there iscurrently considerable interest in the aging researchcommunity in pre-diagnostic studies in cognitive
research and that there is evidence in the area of
psychological health to indicate that late-life
depression is different from early-life depression.
At the end of the day, it was clear that Dr. Salerno’s
visit had enabled RERF scientists to consider somenew areas in which to improve understanding of
the aging process and how that knowledge might
improve RERF’s assessment of radiation-associated risks of health effects.

Dr. Judith Salerno (center) at the aging workshop held in
Hiroshima Laboratory

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Generation of Novel and Versatile Recombinant
Cell Systems That Detect and Measure Genetic
Effects of Radiation*
Asao Noda
Department of Genetics, RERF
*This article is based on the following publication:
Noda A, Hirai Y, Kodama Y, Kretzschmar WW, Hamasaki K, Kusunoki Y, Mitani H, Cullings
HM, Nakamura N. Easy detection of GFP-positive mutants following forward mutations at specific gene locus in cultured human cells. Mutat Res 721:101–7, 2011. (doi:10.1016/j.mrgentox.
2010.12.010)

Introduction
Exposure to ionizing radiation may cause mutations that may have long-lasting effects and they
can be produced in both somatic and germ cells.
Some fraction of the somatic mutants may clonallyexpand, accumulate additional mutations, andeventually develop into a tumor. With regard totumors diagnosed in A-bomb survivors, mutations
in typical oncogenes or tumor suppressor genes,
such as Ras, Raf, TP53, and RET/PTC, have been
analyzed and the results of such studies have beenreported in previous issues of RERF Update.1,2
However, it is not yet clear whether the mutationsof such target genes were from the “direct hit” ofthe radiation or from additional damage incurred
later during the propagation of the affected cells.
Another model of how somatic mutations might
result in cancer development is that there may be atarget cell in the tissue. It is also reasonable toassume that every cell that constitutes a tissue ororgan does not have the same susceptibility todevelop cancer. For example, where the mutant celloriginates from and whether it was in a differentiated cell region or from a stem cell niche may also
be important.
Mutations occurring in germ cells can be transmitted to offspring. While to date no statisticallysignificant increases in genetic effects have been
observed in the children (F1) conceived by A-bomb
survivors after the A-bombs, data are available
from a number of animal experiments. However,
the mutation frequencies for specific loci are generally very low in those animal studies and much
ambiguity exists, particularly in the low-dose rangethat is relevant to the A-bomb survivors.
For the reasons mentioned above, there is anever-ending debate over the shape of the radiation
dose-effect curve regarding low-dose exposuresand cancer risk (or somatic mutation risk) or
Return to Table of Contents

genetic effects (germ cell mutation risk). Althoughanalytical results in the low-dose range have beenreported,3 the view of a “linear relationship without
threshold” has not been universally accepted.4
We wish to help resolve the problems by developing new experimental systems. We are creating
model cells and model animals in an effort to efficiently measure the effects of low-dose radiation
exposure and to obtain locational information
regarding the mutated cells in tissues. Our ultimate
goal is to develop an animal model in which living
cells fluoresce when mutations arise, in order toaccurately measure genetic effects of radiation
exposure, to quantify radiation-induced mutation
frequencies, and identify the locations of target
cells for tumor development. In this article, a cultured cell model will be described as the first stepin achieving our goal.5

Methods and Results
By applying the regulatory systems of the tetracycline gene expression system in E. coli (T-Rex
System, Invitrogen)Ivitrogen) toto mammalianmammaliancells,
cells, we havecreated a system in which mutant cells become
green, because expression of green fluorescent protein (GFP) is induced when a target gene is mutated(functionally destroyed). The following is an outline of the system. Tetracycline repressor (TetR)
gene is inserted into the human HPRT gene locus
to create a cell that can express TetR constitutively.
Subsequently, we introduce into the same cell asystem in which the GFP gene is expressed by tetracycline operator (TetO). So long as TetR protein
is expressed in this cell, GFP will not be expressedfrom TetO. However, when a mutation is caused in
the HPRT gene locus carrying TetR, the supply of
TetR will halt and GFP protein will be expressed,
causing the cell to fluoresce green (Figure 1).
Please refer to the original paper and its Appendix,
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18

Figure 1. Generation of GFP transgenic/TetR knock-in HT1080 cells
cells
HT1080(A) Integration of a single copy of a vector carrying the TetO-EGFPbsr sequence. The left picture indicateslocations of the bsr probe and BamHI site, and the right panel shows the results of Southern blots of 16transfectants.
(B) Diagram illustrating the intracellular system in which GFP transcription is induced by inactivation of TetR
gene which was inserted in intron 3 of HPRT gene by targeted integration, or by inhibition of TetR proteinwith tetracycline.
(C) Veriﬁcation of targeted integration of TetR gene. DNA from the candidate clones were digested with StuIand hybridized with 5c or 3c probes, respectively. Locations of the probes and fragments to be detected
are indicated. In wild-type cells both probes detected the 19.8 Kb band, while in knockin cells 5c and 3c
probes detected the 11.4 and 8.5 Kb bands, respectively.

since the actual gene-targeting approach is much
more complicated.
Naturally, inactivation of TetR protein is caused
by a gene mutation. Such inactivation, however, isalso transiently possible by adding tetracycline to aculture medium (in this case, although TetR protein
continues to be produced in a cell, TetR becomesinactive by its binding with tetracycline [allostericinhibition]). In other words, addition of tetracycline
can make a cell fluoresce as a pseudo-mutant cell,as depicted in Figure 2. Such cells turned brightgreen overnight after being treated with tetracycline (fluorescence intensity of GFP in the cells
was at least 200 times greater than that of control
cells; Figure 2A). With this level of intensity, it ispossible to detect mutant cells readily under a fluorescent microscope (Figure 2B) or by flow cytometer (Figure 2A). Even a mutated cell occurring at afrequency of one per one million can be detected in
one to two minutes. While most of naturally-occurring spontaneous mutations are point mutations
caused by replication errors of chromosomes in S
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phase (misreading of DNA polymerase), many
radiation-induced mutations are said to be due tothe loss of DNA base sequences (wide regions
encompassing dozens of Kb). In fact, fluorescentcells appearing after irradiation (mutants) included
spontaneous mutations and mutations attributableto radiation injury (Figure 2C). In mutants assumed
to be attributable to radiation exposure in particular, the HPRT gene locus itself (encompassing atleast 40 Kb) is lost.
The frequency of occurrence of spontaneousand radiation-induced mutations was analyzed withthe model cells. Cells carry a certain risk of spontaneous mutation. That risk, representing mutabilityof ordinal cells, namely, genetic stability, is called
the spontaneous mutation rate (p). After approximately 20 cell-division cycles, one cell can create apopulation of 220 or about 10 6 (one million) cells.
The number of mutant cells we expect in that cell
population simply depends on a probability event(p), related to when the mutant appears during the
expansion of the proliferating cell population. If
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19

Figure 2. Tet On/Off system verifications and analyses of spontaneous and radiation-related mutants(A) Flow cytometric analyses of HT1080 cells bearing the TetR/TetO-GFP system cultured overnight in theabsence [Tet(–), upper panel] or presence of tetracycline [Tet(+), middle panel]. The lower panel indicates
the window for mutant detection (the mean fluorescent intensity is >250-fold higher than in normal cells).
(B) Two representative views under fluorescent microscopy (X100).
(C) Molecular analyses of mutant clones for the presence or absence of HPRT exons and TetR gene bymultiplex polymerase chain reaction. All spontaneous mutants retained the 8 exons whereas four out ofseven mutants recovered after radiation exposure had lost all of them.

mutant cells appear in early stages of clonal expansion, and the mutants continue to divide at the samerate as other cells, the apparent mutation frequency
will naturally be high. In contrast, if the mutation
occurs at the last cell division in the forming of acell population, the apparent mutation frequency
will be very low. Therefore, even if the mutation
rate (p) is constant, the apparent mutant frequency
will significantly vary depending on when the random event occurs. Although it is possible to use theclassical Luria-Delbrück fluctuation test to calculate spontaneous mutation rate (p) of given cells,
we have developed a formula using a new measurement method and its results. This measurement
method can be characterized as follows: A large
cell population (about 5 × 106–107 cells) in whichmutant frequency is measured in advance is inoculated onto large culture dishes, cultured for shortperiods to get through a few cell divisions (population doublings), and then cell numbers reached arecounted. By obtaining the mutant frequency in thisReturn to Table of Contents

population, mutation rate (p) can be derived. The
following is the formula:
Mf1 − Mf 0 =  p (n0 × 2a −1 )a (n0 × 2a −1 )  = pa
where Mf0 and Mf1 are the mutation frequencies atthe beginning and end of the culture process, respectively, n0 is the number of cells at the time of seeding,and a is the number of cell divisions that took place
during the culture (population doublings). After theseeding of 4 × 106 cells, all of the cells were collected every 3–4 days to measure mutation frequency. This process was repeated, with the results
shown in Figure 3A. Based on Figure 3A and theabove formula, the spontaneous mutation rate (p) of
these cells was calculated to be 3.4 × 10–5/cell division (meaning that mutations occur at a rate of 3.4 ×
10–5 per cell division.). Figure 3B shows the doseresponse curve regarding radiation-induced mutation.
The graph suggests a linear-quadratic curve, withindication of a linear trend in the low-dose ranges.
The doubling dose was about 1 Gy.
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Figure 3. Kinetics for the accumulation of spontaneous
mutations and the dose response for radiation
mutagenesis(A) Mutant frequency at the time of each subculture was plotted against the number of
population doublings.
(B) X-ray dose response. Triplicate measurements were conducted at each dose level.
(C) Radiation dose response at doses below
400 mGy.

Discussion
We have developed a new cell system characterized by the ability to detect a wide range of mutations, from point mutations involving base substitution to megabase (Mb)-level deletions. It istherefore possible to measure not only mutagenic
effects of radiation, but also of other kinds ofchemical and environmental mutagens. In order todetect the number of mutants, conventional methods require colony formation of mutant cells, alarge number of culture dishes, and culturing overmany days. Our system only requires direct counting of the individual mutant cells for calculating
mutant frequency. Since it is possible to insert TetR

gene into any region of a chromosome (targeted
integration) with this method, it should become
possible to measure radiation-induced mutation
frequency in any important gene. Furthermore, thenext step is the creation of a system to measuregenetic effects (somatic mutations as well as germ
cell mutations) of radiation in all the cells in theentire body of a mouse. We hope that our proposedmodel animal will allow accurate measurement ofgenetic effects of low-dose radiation and detectionof radiation-induced mutation of target cells susceptible to carcinogenesis, and thereby provide
supplementary data for use in RERF’s research.

References
1. Eguchi H, Hamatani K, Taga M, et al. Molecular features of colorectal cancer developing among atomic bomb
survivors with emphasis on microsatellite instability—An interim report. RERF Update 18:19-32, 2007.
2. Hamatani K, Ito R, Taga M, et al. Preferential gene alterations in adult-onset papillary thyroid cancer among
atomic-bomb survivors: Chromosomal rearrangements vs. point mutations. RERF Update 19(2):12-8, 2008.
3. Preston DL, Ron E, Tokuoka S, et al. Solid cancer incidence among atomic bomb survivors, 1958–1998.
RERF Update 18:9-13, 2007.
4. Pierce DA, Preston DL. Cancer risks at low doses among A-bomb survivors. RERF Update 12:15-7, 2001.
5. Noda A, Hirai Y, Kodama Y, et al. Easy detection of GFP-positive mutants following forward mutations at
specific gene locus in cultured human cells. Mutat Res 721:101-7, 2011.

Return to Table of Contents

RERF Update Volume 22, Issue 2, 2011

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Science Articles

Effects of Radiation Exposure and Hepatitis Virus
Infection on Risk of Hepatocellular Carcinoma
among Atomic Bomb Survivors*
Waka Ohishi
Department of Clinical Studies (Hiroshima), RERF
*This article is based on the following publication:
Ohishi W, Fujiwara S, Cologne JB, Suzuki G, Akahoshi M, Nishi N, Tsuge M, Chayama K.
Impact of radiation and hepatitis virus infection on risk of hepatocellular carcinoma. Hepatology
53:1237–45, 2011. (doi:10.1002/hep.24207)

Introduction
Hepatocellular carcinoma (HCC) is one of themost common cancers worldwide, and chronic
infections with hepatitis B virus (HBV) or hepatitis
C virus (HCV) are recognized as critically important risk factors for HCC. However, an increase of
non-B, non-C HCC without HBV and HCV infection has been noted recently in Japan.1,2 The etiology of non-B, non-C HCC has been poorly understood, though alcoholic hepatitis, nonalcoholic
fatty liver disease (NAFLD) including nonalcoholic steatohepatitis (NASH), and hemochromatosis3,4 are known as risk factors. In Japan, NAFLD
has increased along with Westernization of lifestyle, and most NASH cases have developed due tosuch lifestyle-related diseases as obesity, diabetes
mellitus, and hyperlipidemia.5 Obesity and diabetes
mellitus, as well as NAFLD, have also recently
received increased attention as risk factors for
HCC.6–12
An increased risk of liver cancer with radiationdose among atomic bomb survivors has beenreported based on tumor registries, mortality studies, and pathology review,13–16 but hepatitis virus
infection status has not been taken into account. On
the other hand, the cohort study in workers at the
Mayak nuclear facility demonstrated that the riskof liver cancer mortality was significantly associated with plutonium exposure,17 and that the incidence of HCC was marginally significantly associated with plutonium exposure. 18 However, livercancer in those analyses included hepatoblastoma
and intrahepatic cholangiocarcinoma as well as
HCC. In addition, hepatitis virus infection status
was not taken into account in a strict and in-depth
manner, though HCC accounted for most of theliver cancer.
With the aim of determining whether radiation
exposure is an independent risk factor for HCC,
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even after adjusting for hepatitis virus infection,
alcohol consumption, BMI, and smoking habits,
we conducted a nested case-control study among
atomic bomb survivors using stored sera. We also
evaluated whether radiation, alcohol consumption,
increase in body mass index (BMI), and smoking
habit contribute to increased risk for non-B, non-C
HCC.

Materials and Methods
Cohorts. The Atomic Bomb Casualty Commission (ABCC) and its successor, RERF, establishedthe Adult Health Study (AHS) longitudinal cohort
in 1958, in which more than 20,000 gender-, age-,and city-matched proximal and distal atomic bomb
survivors and persons not present in the cities at thetime of bombings are examined biennially in outpatient clinics in Hiroshima and Nagasaki.
Cases and controls. Incident cancer cases wereidentified through the Hiroshima Tumor and Tissue
Registry and Nagasaki Cancer Registry, supplemented by additional cases detected via pathological review of related diseases.19 As described in ourprevious study,6 359 primary HCC cases were diagnosed among 18,660 AHS participants between
1970 and 2002, who visited our outpatient clinics
before their diagnosis. Of those, 229 cases had
serum samples obtained within six years before
HCC diagnosis. After excluding five cases withinadequate stored serum, 224 cases remained forour study.
Three control sera per case were selected fromthe at-risk cohort members matched on gender, age,city, and time and method of serum storage, andcountermatched on radiation dose in nested casecontrol fashion.20 Countermatching (to increase
statistical efficiency for studying joint effects ofradiation and other factors) was performed using
four strata based on whole-body (skin) dose.
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Laboratory tests. HBsAg and antibody to hepatitis B core antigen (anti-HBc Ab) were measured
by enzyme immunoassay (EIA), and anti-HCV Ab
was measured by second-generation EIA as previously described.21,22 Qualitative detection of HCV
RNA among anti-HCV-positive samples was performed based on the nested polymerase chain reaction (PCR) method, as previously described. 22
HBV infection (HBV+) status was defined as positive for HBsAg or having a high titer of anti-HBc
Ab. HCV infection (HCV+) status was defined as
positive for HCV RNA. Non-B, non-C status was
defined as negative for HBsAg and not having ahigh titer of anti-HBc Ab (HBV–) as well as negative for HCV RNA (HCV–).
Radiation dose. Radiation dose to the liver was
estimated for each subject according to Dosimetry
System DS02.23 A weighted sum of the gamma
dose in gray plus 10 times the neutron dose in graywas used.
Information on alcohol consumption, BMI,
and smoking habit. Information on alcohol consumption was obtained from the 1965 AHS questionnaire when available, with missing data complemented using the 1978 mail survey. Alcohol
consumption was quantified as volume of each typeof alcoholic beverage; mean ethanol amounts were
calculated as grams per day as previously
described. 24 BMI (kg/m 2) was calculated fromheight and weight measured at the AHS examination. Information on smoking habit was obtained
from the 1965 questionnaire; subjects were categorized as never, current (at time of survey), or former smoker.
Ethical consideration. This study (RERF
Research Protocol 1-04) was reviewed and approvedby the Research Protocol Review Committee and22
the Human Investigation Committee of RERF.
Statistical analyses. The nested case-control
design is analyzed using a partial likelihood
method analogous to that used for cohort follow-up
studies,25 which is in practice the same as the conditional binary data likelihood for matched casecontrol studies26 except that the subjects (cases and“controls”) in the study are not completely independent due to repeated selection. Cumulative incidence of HCC by follow-up time (year) and age
was derived according to the method of Nelson and
Aalen, using Cox regression to adjust for age atstart of follow-up. Cumulative incidence by radiation dose groups (0–0.0009, 0.001–0.999, and 1.0+
Gray) was compared using the Gehan/Breslow
generalized Wilcoxon test. All factors other thanradiation were analyzed using relative risks (RRs)
estimated by a log-linear model. Although radiation exposure could have been adjusted by matching on radiation dose as an additional matching
factor in the control selection,27 in addition toassessing effects of lifestyle factors and viral hepatitis, another purpose of the present study was to
examine effects of radiation exposure after adjustment for possible confounding and interaction by
these factors, so matching on radiation—which
precludes analysis of radiation risk—was not desirable; rather, we countermatched on radiation.20,25,28
Radiation risk was analyzed using an excess relative risk (ERR) model (ERR = RR – 1) as has been
done previously.29

Results
Characteristics of cases and controls. HCC
cases and controls were comparable with respect togender, age, city, and time and method of serum
storage by design. Prevalence of HBV and/or HCV

Figure. Cumulative incidence of HCC (1970–2002) by radiation dose
Dotted line = radiation dose ≥1.0 Gy; dashed line = radiation dose 0.001 ≤ <1.0 Gy; solid line = radiation dose 0 ≤<0.001 Gy. Cumulative HCC incidence by follow-up time (A) and age (B) increased significantly (P = 0.028, P = 0.0003,
respectively) with radiation dose.
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changed little when radiation and hepatitis virus
infection were fit simultaneously (Table 1).
Risk of HCC for radiation after excluding
persons with either or both hepatitis virus infections. The adjusted analyses indicated that radiation exposure was significantly associated withincreased risks for HCC, even after excluding
HBV- or HCV-infected individuals. Furthermore,significant association was found between non-B,
non-C HCC and radiation dose, resulting in RR at 1
Gy of 1.90 (95% CI, 1.02–3.92, P = 0.041) forradiation without adjustment for categorical alcohol consumption, BMI, and smoking habit and 2.74
(95% CI, 1.26–7.04, P = 0.007) with such adjustment (Table 2).
Risk of non-B, non-C HCC. Effects of alcohol
consumption, BMI, and smoking habit on non-B,
non-C HCC risk with or without adjustment forradiation dose were estimated using continuousand categorical covariates. Risk of non-B, non-C
HCC for alcohol consumption per 20 g of ethanol
per day was significant with a log-linear model(adjusted RR 1.64, 95% CI, 1.05–2.81, P = 0.029),
but was limited to the category ≥40 g of ethanol per
day (adjusted RR 5.49, 95% CI, 0.98–39.2, P =0.052). Significant log-linear association was notfound with continuous BMI, and even the category
BMI >25.0 kg/m2 10 years before diagnosis did notevidence significant risk despite a rather large estimate of RR (adjusted RR 3.17, 95% CI, 0.92–12.3,
P = 0.068). Current smoking evidenced significant

infection status in HCC cases is higher than thosein controls. Higher proportions of HCC cases had ahistory of alcohol consumption of more than 40 gof ethanol per day, were obese (BMI >25.0 kg/m2),
and were current smokers, compared with the controls. HCC cases also received on average higher
radiation doses to the liver, compared with the controls.
Cumulative incidence of HCC by radiation
dose. Figures A and B show the cumulative incidence of HCC by radiation dose using either follow-up time (adjusted for age at start of follow-up)
or age. Of 359 HCC cases diagnosed among
18,660 AHS subjects between 1970 and 2002, theanalysis was performed using 322 HCC cases,
based on 16,766 subjects with known radiation
dose. A significant increase with radiation dose wasseen with cumulative incidence both by follow-up
time (P = 0.028) (Figure A) and by age (P =0.0003) (Figure B). The effect of radiation wasespecially evident at age 60 years or later.
Risk of HCC for radiation and hepatitis virus
infection. After adjustment for categorical alcohol
consumption, BMI, and smoking habit, a significant association was found between HCC and radiation dose or hepatitis virus infection, resulting in
an RR at 1 Gy of 1.67 (95% confidence interval[CI], 1.22–2.35, P < 0.001) for radiation and RRsof 63 (95% CI, 20–241, P < 0.001) for HBV+/HCV– status and 83 (95% CI, 36–231, P < 0.001)
for HBV–/HCV+ status. The above estimates

Table 1. Risk of HCC for radiation and HBV or HCV infection status
Variables

Adjusted* RR (95% CI)

Unadjusted RR (95% CI)

Number of
Cases/Controls

Alone

Joint

Alone†

Joint‡

186/600
24/14
119/351.40 (1.07–1.89)
34 (13–106)
57 (27–140)

1.39 (0.93–2.26)
30 (11–91)
58 (28–147)

1.67 (1.22–2.35)
63 (20–241)
83 (36–231)

1.82 (1.09–3.34)
50 (16–184)
87 (37–251)

Radiation (at 1 Gy)
HBV+/HCV–HBV–/HCV+†‡

Abbreviations: CI, confidence interval; RR, relative risk
* Adjusted for categorical alcohol consumption, BMI 10 years before diagnosis, and smoking habit.
†
Radiation dose to the liver and hepatitis virus infection status were fit separately.
‡
Radiation dose to the liver and hepatitis virus infection status were fit simultaneously.

Table 2. Risk of HCC for radiation after excluding persons infected with HBV and/or HCV
Subjects
Exclude HBV+ (no HCV adjustment)(adjust for HCV)
Exclude HCV+ (no HBV adjustment)(adjust for HBV)
Exclude both HBV+ and HCV+†

Number of
Cases/Controls
161/452
66/17642/108

Unadjusted

Adjusted*

RR at 1 Gy (95% CI)

RR at 1 Gy (95% CI)

1.48 (1.10–2.05)
1.60 (0.997–2.78)
1.61 (1.003–2.76)
1.68 (0.96–3.23)
1.90 (1.02–3.92)

1.91 (1.34–2.81)
2.32 (1.25–4.76)
1.91 (1.13–3.48)
2.16 (1.12–4.76)
2.74 (1.26–7.04)

Abbreviations: CI, confidence interval; RR, relative risk
* Adjusted for categorical alcohol consumption, BMI 10 years before diagnosis, and smoking habit.
†
Non-B, non-C status
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risk (adjusted RR 5.95, 95% CI, 1.34–33.2, P =0.018), but there were no continuous data on
amount smoked.

Discussion
The present study confirmed that radiation isassociated with increased incidence of HCC among
atomic bomb survivors. Additionally the nested
case-control study indicates that radiation and
HBV and HCV infection are associated withincreased risk for HCC, and that radiation remains
an independent risk factor for HCC after taking
into account hepatitis virus infection, alcohol consumption, BMI 10 years before HCC diagnosis,
and smoking habit. Furthermore, significant association was observed between non-B, non-C HCC
and radiation dose, alcohol consumption, andsmoking, while obesity 10 years before diagnosis
was marginally significantly associated withincreased risk for non-B, non-C HCC.
In the analysis (Table 1) in which radiation doseand hepatitis virus infection were fitted separately,
radiation was significantly associated withincreased risk for HCC with or without adjustment
for alcohol consumption, BMI, and smoking habit.
Although this finding is in agreement with our previous understanding that liver cancer risk is significantly associated with radiation without adjustment
for hepatitis virus infection among atomic bomb
survivors, it is difficult to compare the HCC risk
estimates between the previous and current study
results.13–16 The difficulty is caused by the inclusionof hepatoblastoma and intrahepatic cholangiocarcinoma in addition to HCC as liver cancer cases inanalyses of tumor registry-based liver cancer risk
(ERR at 1 Sv = 0.49),13 mortality study- and tumor
registry-based15,16 liver cancer mortality risk (male:
ERR per Sv = 0.39, female: ERR per Sv = 0.35),
and liver cancer risk (male: ERR per Gy = 0.32,
female: ERR per Gy = 0.28), despite the fact thatthe majority of liver cancer cases were HCC.
Because a relatively large fraction of liver cancer
cases was included that were diagnosed only on thebasis of death certificates,13,16 complete exclusionof metastatic liver tumor cases from such cases
may not have been possible. Metastatic liver tumor
cases were excluded in an analysis of pathologicalreview-based liver cancer risk (ERR per Gy =0.81), but hepatoblastoma and intrahepatic cholangiocarcinoma were included with HCC.14
In the current analyses adjusted for alcohol consumption, BMI, and smoking habit, the RR estimates for radiation increased slightly and showedstatistical significance with adjustment for HBV
and HCV infection status. HBV infection may be

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24
considered an intermediate risk factor for HCC,
because three of four previous HBV screenings
demonstrated that HBsAg prevalence increases
with radiation dose;30–33 therefore, adjustment for
HBV infection status might be expected to result ina decreased radiation risk estimate. However, suchinterpretation is difficult because the risk estimate
was also adjusted for HCV infection status,
although anti-HCV Ab prevalence is not significantly associated with radiation dose.34 We therefore examined HBV and HCV infection status andconcomitant radiation effects separately, excluding
persons with one or the other viral infection.
RRs of HCC for radiation after excluding persons infected with HBV or HCV were generally
higher than with the full data, but differed little
depending on which virus was used for exclusion(Table 2). As with the full data, adjustment for
HBV or HCV infection status reduced the statistical significance of the radiation effect but had little
impact on the RR estimates themselves. The RR of
HCC for radiation after excluding persons infectedwith HBV and HCV (i.e., the RR of non-B, non-C
HCC for radiation) was significant with or without
adjustment for alcohol consumption, BMI, andsmoking habit. As there can be no viral mediationof the radiation risk in non-infected individuals,
lower radiation risks estimated in infected individuals might be considered evidence of mediation,
but mediation would imply that risk decreases withadjustment for viral infection status, which did notoccur. The reduction in statistical significance withadjustment for HBV and HCV infection status
might be due to loss of power when further parameters for the risks of HCC for hepatitis virus infection are estimated or the number of subjects is
reduced by exclusion.
In conclusion, radiation exposure was associated with increased risk of HCC, even after adjusting for HBV or HCV infection, alcohol consumption, BMI, and smoking habit. Moreover, radiation
exposure was an independent risk factor for non-B,
non-C HCC with no apparent confounding by alcohol consumption, BMI, or smoking habit. The
mechanistic form of joint effects of radiation and
HBV or HCV infection on HCC risk could not be
estimated, but the development of new statisticalmethods that jointly consider the dose response forthe intermediate viral factor will make such ananalysis possible in the future. In particular, indepth understanding of the mechanisms by whichradiation exposure as well as obesity, alcohol
drinking, and smoking contribute to developmentof non-B, non-C HCC may lead to prevention,
early detection, and better therapeutic strategies.

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25

References
1. Umemura T, Kiyosawa K. Epidemiology of hepatocellular carcinoma in Japan. Hepatol Res 37:S95-100,
2007.
2. Abe H, Yoshizawa K, Kitahara T, Aizawa R, Matsuoka M, Aizawa Y. Etiology of non-B, non-C hepatocellular
carcinoma in the eastern district of Tokyo. J Gastroenterol 43:967-74, 2008.
3. Marrero JA, Fontana RJ, Su GL, Conjeevaram HS, Emick DM, Lok AS. NAFLD may be a common
underlying liver disease in patients with hepatocellular carcinoma in the United States. Hepatology 36:134954, 2002.
4. Niederau C, Fischer R, Pürschel A, Stremmel W, Häussinger D, Strohmeyer G. Long-term survival in patientswith hereditary hemochromatosis. Gastroenterology 110:1107-19, 1996.
5. Yoshiike N, Lwin H. Epidemiological aspects of obesity and NASH/NAFLD in Japan. Hepatol Res 33:77-82,
2005.
6. Ohishi W, Fujiwara S, Cologne JB, Suzuki G, Akahoshi M, Nishi N, et al. Risk factors for hepatocellular
carcinoma in a Japanese population: A nested case-control study. Cancer Epidemiol Biomarers Prev 17:84654, 2008.
7. Gupta K, Krishnaswamy G, Karnad A, Peiris AN. Insulin: a novel factor in carcinogenesis. Am J Med Sci
323:140-5, 2002.
8. El-Serag HB, Tran T, Everhart JE. Diabetes increases the risk of chronic liver disease and hepatocellular
carcinoma. Gastroenterology 126:460-8, 2004.
9. Inoue M, Iwasaki M, Otani T, Sasazuki S, Noda M, Tsugane S. Diabetes mellitus and the risk of cancer:
results from a large-scale population-based cohort study in Japan. Arch Intern Med 166:1871-7, 2006.
10. Caldwell SH, Crespo DM, Kang HS, Al-Osaimi AM. Obesity and hepatocellular carcinoma. Gastroenterology
127:S97-103, 2004.
11. Marrero JA, Fontana RJ, Fu S, Conjeevaram HS, Su GL, Lok AS. Alcohol, tobacco and obesity are synergistic
risk factors for hepatocellular carcinoma. J Hepatol 42:218-24, 2005.
12. Saunders D, Seidel D, Allison M, Lyratzopoulos G. Systematic review: the association between obesity andhepatocellular carcinoma—epidemiological evidence. Aliment Pharmacol Ther 31:1051-63, 2010.
13. Thompson DE, Mabuchi K, Ron E, Soda M, Tokunaga M, Ochikubo S, et al. Cancer incidence in atomic
bomb survivors. Part II: Solid tumors, 1958–1987. Radiat Res 137:S17-67, 1994.
14. Cologne JB, Tokuoka S, Beebe GW, Fukuhara T, Mabuchi K. Effects of radiation on incidence of primaryliver cancer among atomic bomb survivors. Radiat Res 152:364-73, 1999.
15. Preston DL, Shimizu Y, Pierce DA, Suyama A, Mabuchi K. Studies of mortality of atomic bomb survivors.
Report 13: Solid cancer and noncancer disease mortality: 1950–1997. Radiat Res 160:381-407, 2003.
16. Preston DL, Ron E, Tokuoka S, Funamoto S, Nishi N, Soda M, et al. Solid cancer incidence in atomic bomb
survivors: 1958–1998. Radiat Res 168:1-64, 2007.
17. Gilbert ES, Koshurnikova NA, Sokolnikov M, Khokhryakov VF, Miller S, Preston DL, et al. Liver cancers inMayak workers. Radiat Res 154:246-52, 2000.
18. Tokarskaya ZB, Zhuntova GV, Scott BR, Khokhryakov VF, Belyaeva ZD, Vasilenko EK, et al. Influence ofalpha and gamma radiations and non-radiation risk factors on the incidence of malignant liver tumors among
Mayak PA workers. Health Phys 91:296-310, 2006.
19. Fukuhara T, Sharp GB, Mizuno T, Itakura H, Yamamoto M, Tokunaga M, et al. Liver cancer in atomic-bomb
survivors: histological characteristics and relationships to radiation and hepatitis B and C viruses. J Radiat
Res (Tokyo) 42:117-30, 2001.
20. Improving the efficiency of nested case-control studies of interaction by selecting controls using countermatching on exposure. Int J Epidemiol 33:485-92, 2004.
21. Ohishi W, Fujiwara S, Suzuki G, Kishi T, Sora M, Matsuura S, et al. Feasibility of freeze-dried sera forserological and molecular biological detection of hepatitis B and C viruses. J Clin Microbiol 44:4593-5, 2006.
22. Ohishi W, Fujiwara S, Suzuki G, Chayama K. Validation of the use of freeze-dried sera for the diagnosis ofhepatitis B and C virus infections in a longitudinal study cohort. In: Mohan RM, ed. Research Advances in

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RERF Update Volume 22, Issue 2, 2011

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Science Articles
Microbiology 7. Kerala, India: Global Research Network; 2007. p. 1-9.

23. Young RW, Kerr GD, eds. Reassessment of the Atomic Bomb Radiation Dosimetry for Hiroshima andNagasaki—Dosimetry System 2002. Hiroshima, Japan: Radiation Effects Research Foundation; 2005.
24. Sharp GB, Lagarde F, Mizuno T, Sauvaget C, Fukuhara T, Allen N, et al. Relationship of hepatocellular
carcinoma to soya food consumption: a cohort-based, case-control study in Japan. Int J Cancer 115:290-5,
2005.
25. Langholz B, Borgan Ø. Counter-matching: A stratified nested case-control sampling method. Biometrika
82:69-79, 1985.
26. Breslow NE, Day NE. Statistical Methods in Cancer Research: Volume 1—The Analysis of Case-control
Studies. Lyon, France: International Agency for Research on Cancer; 1980.
27. Cologne JB, Shibata Y. Optimal case-control matching in practice. Epidemiology 6:271-5, 1995.
28. Cologne JB, Langholz B. Selecting controls for assessing interaction in nested case-control studies. J
Epidemiol 13:193-202, 2003.
29. Cologne JB, Tokuoka S, Beebe GW, Fukuhara T, Mabuchi K. Effects of radiation on incidence of primaryliver cancer among atomic bomb survivors. Radiat Res 152:364-73, 1999.
30. Kato H, Mayumi M, Nishioka K, Hamilton HB. The relationship of hepatitis B surface antigen and antibody
to atomic-bomb radiation in the Adult Health Study sample, 1975–1977. Am J Epidemiol 117:610-20, 1983.
31. Neriishi K, Akiba S, Amano T, Ogino T, Kodama K. Prevalence of hepatitis B surface antigen, hepatitis B eantigen and antibody, and antigen subtypes in atomic-bomb survivors. Radiat Res 144:215-21, 1995.
32. Fujiwara S, Sharp GB, Cologne JB, Kusumi S, Akahoshi M, Kodama K, et al. Prevalence of hepatitis B virus
infection among atomic bomb survivors. Radiat Res 159:780-6, 2003.
33. Belsky JL, King RA, Ishimaru T, Hamilton HB, Nakahara Y. Hepatitis-associated antigen in atomic bomb
survivors and nonexposed control subjects: seroepidemiologic survey in a fixed cohort. J Infect Dis 128:1-6,
1973.
34. Fujiwara S, Kusumi S, Cologne JB, Akahoshi M, Kodama K, Yoshizawa H. Prevalence of anti-hepatitis C
virus antibody and chronic liver disease among atomic bomb survivors. Radiat Res 154:12-9, 2000.

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RERF Update Volume 22, Issue 2, 2011

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Science Articles

Lifetime Risk of Stroke and Impact of Hypertension:
Estimates from the Adult Health Studyin Hiroshima and Nagasaki*
Ikuno Takahashi
Department of Clinical Studies (Hiroshima), RERF
*This article is based on the following publication:
Takahashi I, Geyer SM, Nishi N, Ohshita T, Takahashi T, Akahoshi M, Fujiwara S, Kodama K,
Matsumoto M. Lifetime risk of stroke and impact of hypertension: Estimates from the Adult
Health Study in Hiroshima and Nagasaki. Hypertens Res 34:649–54, 2011. (doi:10.1038/
hr.2011.7)

Introduction
With the aging of Japan’s population, stroke has
become an ever more important health burden, andthus activities aimed at stroke prevention require
urgent attention. While elevated blood pressure(BP) has emerged as one of the prominent risk factors for stroke, when to start treatment of hypertension and what levels of hypertension require medication remain undetermined issues. In particular, apoint of great debate is whether prehypertension
conditions signify a risk of stroke.
It has been suggested that competing events in
non-stroke death may cause bias in risk estimatesof stroke based on longitudinal observations.1 The
aim of our study is to clarify the importance ofhypertension management for the purpose of risk
prevention, by calculating the association between
lifetime risk (LTR) of stroke with consideration ofcompeting risks and several baseline age BP categories.
Methods
This study was comprised of some of the
RERF’s Adult Health Study (Hiroshima, Nagasaki)
participants, who have been followed through biennial health examinations over a period of more than
50 years (20,000 subjects in 1958, the start of follow-up; follow-up rate 100%; participation rate forhealth exams over 70%). We calculated LTR of
stroke for various blood pressure-based groups
among 7,847 subjects who had no history of stroke
before the baseline ages of 55 years or younger andwho underwent blood pressure measurements
between the ages of 55 and 56, using cumulative
incidence analysis and adjusting for competingrisks. The observation period was 1958–2003.
First-ever stroke cases were identified by clinicalrecords, death certificates, and autopsy records inReturn to Table of Contents

accordance with the definitions in the World HealthOrganization (WHO)-initiated Monitoring ofTrends and Determinants in Cardiovascular Disease (MONICA) Project. Analyses of LTR of
stroke in the various baseline-age cohorts of 45, 55,
65, and 75 years were carried out after adjustment
was made for competing risk of non-stroke death.
BP groups were defined in accordance with criteria
from the Seventh Report of the Joint National
Committee on the Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC
7): normal, <120/80 mmHg; prehypertension,
120–139/80–89 mmHg; stage 1 hypertension,
140–159/90–99 mmHg; and stage 2 hypertension,≥160/100 mmHg.

Results
The Table indicates characteristics of the 7,487
subjects, who were observed from the baseline age
Table. Characteristics at the baseline age of 55 years
Men
Blood pressure

NormalPrehypertension
Stage 1 hypertension
Stage 2 hypertension

[%]

20.0
34.5
26.4
19.1

Body mass index (median)[kg/m2]

21.8

Total cholesterol (median)[mg/dl]

179

[%]

27.0
34.9
22.3
15.7

Body mass index (median)[kg/m2]

22.6

Total cholesterol (median)[mg/dl]199

Women
Blood pressure

NormalPrehypertension
Stage 1 hypertension
Stage 2 hypertension

RERF Update Volume 22, Issue 2, 2011

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Science Articles

Figure 1. Cumulative incidence, accounting for competing risk

Figure 2. Cumulative incidence of all stroke by blood pressure groupof 55 years. LTR of all stroke was 20.5% in men
and 22.2% in women (Figure 1). Female LTR was
slightly higher than male LTR. BP was a significant
factor in determining risk of stroke for men andwomen, with distributions of cumulative risk forstroke significantly different across BP groups(Figure 2). Separated into ischemic/hemorrhagic
strokes, results followed the same pattern. For men,
LTR of ischemic stroke for normotension, prehypertension, stage-1 hypertension, and stage-2
hypertension was 11.2, 10.7, 18.3, and 17.3%,
respectively, while LTR of hemorrhagic stroke was
1.5, 4.2, 5.4, and 6.4%. For women, LTR of ischemic stroke was 11.3, 13.1, 14.5, and 18.4%,
respectively, while LTR of hemorrhagic stroke was
3.7, 4.7, 6.2, and 8.9%. The estimates did not differ
significantly among any of the baseline ages of 45,
55, 65, and 75 years.
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Discussion
Few reports have been published on LTR of
stroke: one each from the United States (theFramingham Study), 1 Holland (the Rotterdam
Study),2 and Japan (the Suita Study).3 Ours is thefirst report to investigate the relationship between
LTR of stroke and BP at each baseline age. LTR of
all-stroke in our study was similar to the reported
results from the previous studies. Our longitudinal
study using LTR estimates indicated that hypertension in midlife remained a risk factor for stroke
compared with normotensive subjects. Regarding
the controversial issue of impact from prehypertension (120–139/80–89 mmHg) on stroke events, ourresults did not indicate significant risk of stroke inthat category.

RERF Update Volume 22, Issue 2, 2011

Science Articles

Conclusion
Our study suggests that hypertension at midlife
among Japanese subjects affects LTR for stroke. It
is therefore important to address this risk early on,

29
when hypertension is first diagnosed to ensure that
effective therapy can be initiated and stroke risk islowered.

References
1. Seshadri S, Wolf PA. Lifetime risk of stroke and dementia: Current concepts, and estimates from the
Framingham Study. Lancet Neurol 6:1106–14, 2007.
2. Hollander M, Koudstaal PJ, Bots ML, Grobbee DE, Hofman A, Breteler MM. Incidence, risk, and casefatality of first ever stroke in the elderly population. The Rotterdam Study. J Neurol Neurosurg Psychiatry
74:317–21, 2003.
3. Turin TC, Kokubo Y, Murakami Y, Higashiyama A, Rumana N, Watanabe M, Okamura T. Lifetime risk ofstroke in Japan. Stroke 41:1552–4, 2010.

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RERF Update Volume 22, Issue 2, 2011

30

Human Interest Notes

Unveiling Ceremony of Monument Honoring
Barbara Reynolds
A monument honoring Ms. Barbara Reynolds, aU.S. peace activist who protested against nuclear
arms all over the world together with Hiroshima’s
A-bomb survivors, was erected in the Hiroshima
Peace Memorial Park. The unveiling ceremonyon June 12, 2011 was organized by the World
Friendship Center, an organization Ms. Raynolds
worked hard to establish, and attended by about
110 individuals including Barbara’s family members and A-bomb survivors who joined her in peaceand anti-nuclear activities.
Barbara first came to Japan in 1951 accompanying her husband Earle Reynolds who worked at theAtomic Bomb Casualty Commission (ABCC),
RERF’s predecessor. Shocked by the devastation
caused by the atomic bomb, she continued herappeal for peace and abolition of nuclear weapons,traveling on peace pilgrimages and conducting
other activities, with A-bomb survivors. At the endof their voyage in 1960 as they pulled into
Hiroshima’s harbor, they were greeted as heroes.
People thanked them for telling the world what
happened in Hiroshima and for sailing into therestricted zone in an attempt to stop the testing of
nuclear bombs in the Marshall Islands. In 1975, she
was named a special honorary citizen of Hiroshima.
The words she often spoke “I, too, am a hibakusha”
are inscribed on the monument.
RERF Chairman Toshiteru Okubo made anaddress at the unveiling ceremony, followed byspeeches from Hiroshima Mayor Kazumi Matsui,
Hiroshima Municipal Assembly President Takashi
Kijima, and Hiroshima University Extraordinary
Professor Tadatoshi Akiba (former Hiroshima
mayor). Following are Dr. Okubo’s address and theremarks made by Mrs. Jessica Reynolds Renshaw,
Barbara’s daughter.

Address made by RERF Chairman Toshiteru
Okubo [excerpted]
Dr. Earle Reynolds, who was Barbara’s husband
and an anthropologist, was assigned to investigate
the effects of A-bomb radiation on children at theformer Atomic Bomb Casualty Commission(ABCC), presently Radiation Effects Research
Foundation (RERF), where I work. Beginning in
1951 he conducted research by studying the children for three years. In 1954 the results of his studies were published in a journal of the Pediatrics
Society of Japan.
The RERF has investigated the medical effectsof radiation on human health and related diseases.
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Although this research began as a result of the terrible disaster of the exposure to the A-bomb, it waspossible thanks to the understanding and cooperation of many A-bomb survivors and others. Now
the result of that research contributes to interpretation of important knowledge for medical care forthe radiation-exposed caused by nuclear accidents
and medical exposures as well as for A-bomb survivors.
Hibakusha didn’t use their tragic experiences
for an act of “retaliation.” On the contrary, they
firmly agreed to use that experience for prayer anda desire for peace. We sympathize with them about
this matter from the bottom of our hearts. Barbara,too, must have been strongly moved to desire world
peace, for she lived in Hiroshima shortly after the
war and saw the hibakusha’s way of living.
From now on, as future generations pass in frontof this monument near the cenotaph in Peace
Memorial Park, I wish they will continue her
appeal for the total abolition of nuclear weapons. In
conclusion I’d like to thank all of those who continue to follow her will and are devoted to thedevelopment of the World Friendship Center.
Thank you very much.

Remarks made by Jessica Reynolds Renshaw[excerpted]
Dear Members of the Monument Committee,
hibakusha, friends, and family,
We are happy to meet with you today. My husband Jerry and I have come from California and mynephew Tony, one of Barbara’s grandsons, hascome from Texas. We also represent my brothers,
Barbara’s sons Tim and Ted Reynolds, and herother eight grandchildren who would have come if
possible.
We are here at the invitation of the Dedication
Committee to unveil a monument to my mother,
who would have been 96 years old today. To me, it
is amazing that the hibakusha of the nuclear bomb
dropped by Americans would erect a monument toan American woman at their Ground Zero. I am sohumbled by your forgiveness and desire to do this.
Many people whose lives have been touched by mymother’s life call her a saint, even a “national treasure.” But my mother would have been the first to
say she was just an imperfect human being.
In September, 1964, my mother was 49 years
old. Years before, my father had been part of a teamsent by the American government to study theeffects of radiation on Hiroshima hibakusha—to
RERF Update Volume 22, Issue 2, 2011

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Human Interest Notes
draw their blood, measure their height and weight,
and so on. But no one had asked them, “What was
it like to experience an atomic bomb?” No one hadlistened to them or cried with them. Now, in obedience to her heavenly Father, my mother went backto Hiroshima, despite her sense of personal shame,to listen to them and serve them, to be God’s hands
and feet and voice. Out of her humility and obedience bloomed the World Friendship Center.
She was not only a voice from the heavenly
Father to the hibakusha. Hibakusha told her they
considered her a voice for Hiroshima and Nagasaki
to the world. She took that responsibility very seriously. And as she came to know them, they taught
her the value of each life. She came to respect thebrave, suffering, patient survivors of the first two
nuclear bombs dropped on human beings. She
began to identify with them and hurt for them. And
so she said, “I, too, am a hibakusha.” She wanted toaccurately convey to the world their message, “No
more Hiroshimas!” to urge everyone on the planet

Dr. Toshiteru Okubo speaks at themonument’s unveiling ceremony

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to choose peace and prevent the horror and catastrophe of Hiroshima from happening to anyone
else, ever.
Since 1945, starting in Hiroshima and Nagasaki,
the number of people exposed to the poison ofradiation has grown through Chernobyl, ThreeMile Island and now Fukushima. Radiation does
not distinguish between war and peace. Radiationfrom nuclear weapons keeps killing after the war isover. We are here to assure all radiation-exposed
people anywhere that we will not forget your distress. We will pass your message on from generation to generation: “No More Hiroshimas!” “No
more Nagasakis!” “No more Fukushimas!”
As you unveil this monument, my mother is justa symbol. She is a symbol of love, pointing to thesource of love, the heavenly Father. She is a symbolof hope because anyone of us who humbles himself
to listen to the “still, small voice” of our Heavenly
Father can make a mighty difference. Thank you
for honoring my mother in this way.

(from left) Mr. Jerry Renshaw, Mrs. Jessica Renshaw (Barbara Reynolds’
daughter), Mr. Tony Reynolds (Barbara Reynolds’ grandson), and Mr.
Hiromu Morishita (Chairman of the World Friendship Center)

RERF Update Volume 22, Issue 2, 2011

32

Human Interest Notes

Report on the Health Examinations for A-bomb
Survivors in North America
Akihiko Suyama, Chief
Department of Epidemiology, Nagasaki
It was my third time to join in a medical teamfor health examinations of A-bomb survivors inNorth America and, for the first time, I traveled to
Los Angeles and Honolulu.
The Los Angeles and Honolulu medical teamwas headed by Dr. Makoto Matsumura (Permanent
Director, Hiroshima Prefectural Medical Association [HPMA]), with Dr. Shizuteru Usui (President,HPMA) as general leader, and consisted of elevenmembers, namely seven medical doctors including
myself and four administrative staff members from
HPMA, Hiroshima City/Prefecture, Nagasaki City/
Prefecture, and RERF (Mr. Hideo Shinoda). The
Seattle and San Francisco medical team was led by
Dr. Jitsuro Yanagida (Permanent Director, HPMA),
and also consisted of seven medical doctors, including Dr. Yoshimi Tatsukawa (RERF) and four administrative staff members from the aforementioned
organizations. Detailed reports from these medical
teams are posted on the website of HPMA (Ishikai
Sokuho No. 2125 and No. 2128; in Japanese).
Since Japanese physicians do not usually have alicense to practice medicine in the U.S., we are notallowed to perform such medical procedures as
health examinations or explanations of test results.
The health examinations by Japanese doctors had
been supervised by American physicians with a
U.S. medical license, but in Honolulu this time, asa trial attempt, a doctor from Japan together with a
U.S. physician licensed by the State of Hawaii
jointly performed the examinations.
Professor Jerris Hedges (emergency medicalcare), Dean of the School of Medicine, the University of Hawaii, and Dr. Fernando V. Ona, a leading
specialist in gastroenterology in Honolulu, provided me support on different days. It took me
considerable effort to carry out the health examinations, explaining in English the medical records
written in Japanese and having Drs. Hedges andOna perform the examinations from time to time.
However, I was able to observe directly how U.S.
doctors communicated with and handled examinees in a U.S. examination room. I also had a chance
to talk with those experienced medical practitioners
about how we would handle suspected disease inconsideration of various clinical guidelines in the
U.S., and that’s where I sometimes noticed slightdifferences in approaches between the U.S. andReturn to Table of Contents

Japan.
In addition to the generation of examinees
speaking Hiroshima dialect, there were also an
increasing number of examinees wanting toundergo the examinations in English. I felt that the
aforementioned collaboration with such skillful
U.S. doctors in the examinations further enhanced
the examinees’ confidence in our medical team
based on Japanese support for the A-bomb survivors
in the U.S. Some examinees, however, still expected
to be examined by Japanese doctors like the previous examinations, and it therefore may be time for
us to review what is expected from the future medical teams for this North America program.
When I first participated in the North America
program in 2005, some examinees in Seattle and
San Francisco told me that I was the first doctorfrom Nagasaki to participate in the health examinations. Receiving such a comment was only natural,since the North America program had been promoted by HPMA. The reality is, however, thatmany examinees were exposed to the A-bombing
in Nagasaki, and I thus perceived their considerable
expectation for participation by a physician from
Nagasaki. I traveled with medical teams to Seattle
and San Francisco in 2005 and 2007, and after
returning to Japan, I had several experiences ofreceiving long-distance telephone calls from the
U.S. from the examinees telling me about theirreturning to Nagasaki for treatment and actually
meeting with the examinees in Nagasaki and hearing of their misgivings about treatment in the U.S. I
was fortunate to participate in the North America
program as a medical team member on the threeoccasions I indicated above while a physician
belonging to the RERF Nagasaki Laboratory, and I
feel that my participation in the medical teamsomewhat contributed to provide a sense of relief
to the examinees exposed to the atomic bomb in
Nagasaki and now living in North America.
The North America program began in 1977 as acooperative project between HPMA and RERF.
The biennial health examination program was
entrusted to Hiroshima Prefecture as a national
government program in 2007, and later to HPMA
from the prefectural government. RERF collaborated in dispatching doctors and administrative
staff members to the program for many years, andRERF Update Volume 22, Issue 2, 2011

33

Human Interest Notes
since 2011 handled activities including preparationof a report after the health examinations as work
officially entrusted by HPMA.
When I joined the North America program forthe first time in 2005, I learned many things fromthree publications—“Were We the Enemy? American Survivors of Hiroshima (English translation)”by Rinjiro Sodei, and “Ikinokotta Hitobito (Survivors),” Volumes I & II (Japanese) by Fuyuko
Kamisaka. From Mr. Sodei’s book in particular, I
learned so much about the history of RERF’s
involvement in the North America program. Mr.
Hiroaki Yamada, a former ABCC employee, put
forth great effort in initiating the North America
program. Many people have supported the program
through various interactions in the four cities of
Seattle, San Francisco, Los Angeles, and Honolulu,
including the A-bomb survivors, either as groups orindividuals, who prepared examinee lists and handled relevant contacting work, hospitals/clinics
providing volunteer medical staff, who worked on
weekends to support work related to the healthexaminations and venues, other volunteer groups as
friends of A-bomb survivors consisting of nonsurvivors, and people from associations of Japanese physicians residing in the U.S., among somany others. In terms of making contact with thosepeople, people like Mr. Yamada of ABCC and more
recently Mr. Tadaaki Watanabe of RERF had afeeling for the survivors in North America from ahumanitarian viewpoint, and made efforts ignoring
their own individual sacrifices for the sake of RERF
as an organization and occupation, and thus I cannot
help but think the efforts made by ABCC and
RERF staff ensured that the program has been
maintained to this point without losing ties with all
those involved.
Chief of Secretariat Midori Mukai of HPMA,
who started her involvement with this most recent
program, made every effort to maintain the humanties developed so far, and I saw firsthand her prepa-

rations in North America for the program.
RERF’s future involvement in the North America
program will be reviewed on the basis of the resultsfrom the latest project. It is my strong desire that
the North America program be continued without
lapse to the next round of examinations, learningfrom its legacy built jointly by ABCC-RERF and
HPMA since the program’s start.
Finally, I was asked to explain the radiation
effects from the Fukushima Dai-ichi nuclear power
plant crisis, when we visited the Los Angeles county’s medical association, Providence Little Company of Mary Medical Center Torrance (venue forthe health examinations), and the Japanese Consulate General. Interest in the nuclear crisis in
Fukushima was incredibly high in Los Angeles,
since there is a nuclear reactor located not very far
from the city, and Los Angeles is in a seismically
active region. When the health examination group
visited the U.S. in June, however, understanding of
the situation surrounding the nuclear crisis was lessclear than it is now. Comparing the three occasionsof my participation in the North America program,I felt the magnitude of my responsibility mostacutely this time, since only RERF was responsible
for, as specialists, explaining from a scientific perspective radiation’s human health effects. Dr.
Makoto Matsumura, who reported on his visit to
the devastated Fukushima area to provide support,
also indicated that RERF’s continued role in the
North America program as an expert organizationin A-bomb radiation research was strongly anticipated. I was reminded then that RERF is involvedin the program as the sole comprehensive radiation
specialist organization, and that in addition to conducting collaborative studies at RERF, it will be
important for us, without resting on our laurels, toprepare ourselves to be able to explain an extensive
range of issues related to radiation effects in emergency situations such as the much talked about
Fukushima nuclear crisis.

The U.S. and Japanese staff involved in the A-bomb survivors’ health examination programin Los Angeles. Dr. Akihiko Suyama is the second person from right in the first row.
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RERF Update Volume 22, Issue 2, 2011

34

Human Interest Notes

In Memoriam: Mrs. Ruth W. Beebe
We were saddened to learn that Ruth W. Beebe
died on November 19, 2011, 16 days before her
99th birthday. Born on December 5, 1912, Ruth iswell known to the RERF community as she was thewidow of Gilbert Beebe, one of the most influential
figures in terms of the early days of the Atomic
Bomb Casualty Commission (ABCC) and theestablishment and implementation of the cohort
studies which are the hallmark of today’s RERF
epidemiological research. Ruth was a graduate ofSmith College and met her husband Gilbert when
they both had summer jobs at Rockaway Beach,
New York. They were married in 1933 andremained married until his death in 2003.
Ruth was trained as a clinical psychologist andreceived an MA in psychology from Columbia
University in 1936. She did doctoral work in psychology at Columbia University Teachers College.
In 1943, she took a job at the Child Study Center ofMaryland in Baltimore to be near her husband Gilbert who was an Army Captain in the Surgeon General’s Office in Washington, DC, soon to become
involved in the ABCC. From 1944 when she moved
to Washington after the birth of her first child, until
1984 when she retired from Montgomery County
Public Schools, Ruth worked full-time as a clinicalpsychologist and as a child and school psychologist
in the Washington area. Having lost her own
mother at age 7, Ruth was a loving and devoted
mother to her four children. In her retirement she
was a volunteer in a number of public service
activities. For example, in 1969 and 1970 she participated in and was a leader of more than a dozen
workshops on black-white relations and racism.
Since 1985, she was a member of the WashingtonTokyo Women’s Club.
In 1958, she traveled to Japan with her four children to live for two years while her husband served
as Chief of Statistics at ABCC in Hiroshima andNagasaki, Japan. They were to return for two-year
assignments in 1966 and 1973 where Gilbert established and secured his reputation and legacy as a
devote supporter of ABCC and RERF research. But

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Ruth was also very busy in Hiroshima. She worked
as a school psychologist for the Department of
Defense Dependent Schools in Japan and psychological consultant at the American School in Japan,
ASIJ. In addition, she gave courses in the University of Maryland Overseas Program’s Far East
Division, and at Hiroshima University. She was an
instructor for the Mazda Motor Corporation and a
consultant for the Hiroshima International School
which is celebrating its 50th anniversary this year.
After her husband’s death in 2003, Ruth began along descent into dementia while maintaining good
physical health. According to her son Alfred, shedied peacefully in her home in the company of her
youngest son, his daughter, and her caregiver,Marie Davids. She is survived by a daughter Beatrice and three sons, Alfred, Brian, and Christopher,and by five grandchildren and two great grandchildren. The family has asked for donations in honorof Ruth White Beebe to be made to the Alzheimer’s
Association (www.alz.org) or to the Alzheimer’sFoundation of America (www.alzfdn.org). The
family should rest assured that many readers of thisRERF Update will have many fond memories of
their mother.

Ruth W. Beebe (center) with her husband Gilbert (right) andson Alfred (left) at the First Annual Gilbert W. Beebe Symposium held at the National Academies in Washington, DC,
2002.

RERF Update Volume 22, Issue 2, 2011

35

Facts and Figures

A Surge in RERF Website Accesses
In response to the Fukushima Dai-ichi nuclear
power plant accident on March 11, RERF notified
the general public on March 15, on its website’s“What’s New” page, of the availability of brochures describing radiation and its effects onhuman health. On March 17, a special webpage
devoted to the nuclear power crisis was created toprovide additional information. The new webpage
included a collection of questions and answers
regarding radiation health effects, some relevant
brochures, a listing of institutes related to healthcare for the radiation-exposed in Japan, and otherrelated information from both Japan and abroad.
An English version of the webpage was madeavailable on March 18, and thereafter, the webpage
has been updated when necessary.
During the same time period, RERF website
accesses dramatically increased. The number ofdaily hits (including hits by a search engine) andvisits (actual visits to the RERF homepage)increased from about 40,000 and 1,300, respectively, before the disaster to about 2 million and
30,000, respectively, afterwards (as of March 15).
Thereafter, the numbers gradually decreased but
remained about five times as many as the pre-accident numbers over a period of several months.
Around September, six months after the accident, the access numbers returned to nearly preaccident levels. The table below shows thenumbers regarding RERF website access fromFebruary 2011 (before the accident) throughOctober 2011.
Furthermore, the “Research Questions”
page on the external website has received alarge number of questions from both inside andoutside Japan during the period from the immediate aftermath of the accident to the present. In
addition, about 20 organizations, including
municipal governments, public research insti-

tutes, and libraries, have requested a link to the
RERF website. Visitors to the Hiroshima Laboratory also have drastically increased: that number
from both inside and outside Japan during theperiod from January through November 2011reached 1,640 people, excluding the 1,375 visitors
to the Open House event. We have also received
requests for radiation-related lectures from various
groups and individuals, including community centers, schools, businesses, and physicians, and in
response, RERF officers and research scientists
provided lectures at 14 venues, including Sendai,
Nagoya, and Okinawa, from April until the end of
this November. Reservations have been made fordispatching RERF lecturers through February
2012.
In summary, Japan and the world have turned tothe contributions and participation of the A-bomb
survivors, and the results of the studies and analyses of RERF scientists, for a better understandingof the potential health risks associated with theevents happening in northern Japan. We will continue to try our best to make the results of ourresearch known as we apply for a public-interest
incorporated foundation status.

Access to the RERF Website(February–October 2011)
No. of Hits

No. of Visitors

February

1,119,216

37,174March

15,372,871

280,447

April

7,858,477

145,136May

6,297,095

121,818

June

4,842,019

93,466

July

3,710,524

81,469August

4,830,586

94,307

September

1,422,851

31,124

October

3,623,405

65,854Return to Table of Contents

RERF Update Volume 22, Issue 2, 2011

Research Protocols

Research Protocols Approved in
May–October 2011
RP 4-11 Genetic Study of Atomic-bomb Radiation by Using HD-microarray CGH Analysis
Kodaira M, Satoh Y, Furukawa K, Nakamura N,
Asakawa J
The genetic effects of atomic-bomb (A-bomb)radiation (trans-generational effect) have not been
fully elucidated due to low rates of both spontaneous mutation and radiation-induced mutation in
germ cells. Since radiation-induced mutations areprimarily deletions initiated with DNA doublestrand breaks, we propose a comparative genome
hybridization (CGH) study using high-density
microarrays. In the proposed study, we will analyze
a total of 688 DNA samples from both parents of
184 families (high-dose exposure is limited toeither parent) and 320 offspring (160 from paternally and 160 from maternally exposed families).
We plan to use a 3 × 1.4 M high-density microarraythat contains three identical sets of 1.4 million
probes (average interval 2.2 kb) on a single slide.
The multiplex format of the microarray permits us
to analyze three DNA samples at a time on a single
slide. We will determine the parental origin of
mutations to be detected based on the single nucleotide polymorphism (SNP) information existing in
the genome region involved in the mutational
events. The analyses of 320 offspring will enable
us to test 7.36 × 106 loci that were exposed andunexposed, respectively, assuming that our genome
consists of 23,000 genes. If we use the currently
available mutation rates obtained through irradiation of spermatogonia of male mice, we would
expect 16.2 mutations (95% confidence interval[CI]: 9–25) among the exposed paternal alleles and3.7 mutations (95% CI: 0–8) among the unexposedalleles (the estimated statistical power to detect
radiation effect is more than 80%). On the other
hand, we do not expect enough mutations in 160
offspring of the maternally exposed families todetect an elevated rate because the mutation rate
obtained in irradiated rat immature oocytes seems
to be much lower than that in mouse spermatogonia. Nonetheless, this group is indispensable
because the paternal alleles are not exposed toradiation and hence serve as the control of theabove-mentioned paternally exposed families. The
analyses will provide far more information than iscurrently available on the risk associated witheither maternal or paternal radiation exposure.
RP 5-11 Extension of Study Period (to 2005)
and Amendment of Review Procedures of the“Studies on Thyroid Tumor Incidence among
the RERF Extended Life Span Study Cohort,
Return to Table of Contents

36
1950–87” (Addendum to RP 6-91)
Ozasa K, Yonehara S, Ito M, Tokuoka S, Sekine I,
Suyama A, Furukawa K, Mabuchi K
A site-specific cancer study for the thyroid
gland has been underway for the period of 1950–95(the period was originally defined as 1950–87, thenextended to 1995). However, the period of 1950–95
seems to be outdated and needs to be extended
again. We also propose to amend the methods
for the pathological review to shorten the study
period. This is based on the findings in the study
for 1950–95 that the reviewers’ diagnoses for thyroid tumors were mostly consistent with the registry’s diagnoses in recent years. This memorandum
describes an extension of the study period andamendment of the pathological review proceduresin the RP 6-91.
RP 6-11 A Study of Chromosome Aberration
Frequency in Thyroid Cells Following Fetal
Exposure to Ionizing Radiation in Mice
Hamasaki K, Noda A, Nakamura N, Hsu WL,
Kodama Y
Through epidemiologic studies on childhood
cancer conducted since the 1950s, it has been suggested that fetuses are highly sensitive to radiation
for induction of cancers. However, whether thethird-trimester exposure to diagnostic X rays has
induced childhood cancers or not is still under
debate. At RERF, we found that peripheral blood
lymphocytes of A-bomb survivors who were
exposed in utero did not record chromosome damage when examined at the age of about 40 years,
while the lymphocytes of the mothers showed aclear dose-related increase of translocation frequencies. A similar lack of response was obtainedin mouse lympho-hematopoietic cells (peripheral
blood T cells, spleen T cells, and bone marrowcells) following fetal irradiation and examination in
adult mice. However, our latest results in rat mammary epithelial cells showed that the radiation
effect (chromosome aberrations) was clearly maintained in adult rats that were irradiated as fetuses,
and the frequency was nearly the same as that of
the irradiated mothers. Therefore, it is suggested
that chromosome aberration frequency in adults
following fetal irradiation may vary among tissues.
In the present study, we propose to examine thyroid
epithelial cells in mice to see whether or not theradiation effect may be recorded like mammary
epithelial cells following fetal irradiation. The thyroid cells were chosen since the thyroid gland is
known to be one of the organs more susceptible toradiation-induced carcinogenesis as is the mammary gland. The results may help to explain thecancer risks of A-bomb survivors who were
exposed in utero.

RERF Update Volume 22, Issue 2, 2011

37

Recent Publications

RP 7-11 Preservation of Fresh Thyroid Samples Obtained from Adult Health Study Participants (Addendum to RP 2-86)
Imaizumi M, Ohishi W, Sera N, Hida A, Yamada M,
Hamatani K, Suyama A, Ozasa K, Fujiwara S,
Akahoshi M
Thyroid cancer is one of the cancers mostaffected by radiation and shows increased incidence with increase of radiation dose among
A-bomb survivors. In recent years, genetic studiesof thyroid cancer have achieved significant progress mainly in terms of RET/PTC rearrangements
and BRAF mutations. However, it is not the casethat mechanisms behind thyroid cancer development and radiation effects on such mechanisms are
fully understood. For elucidation of molecularmechanisms of thyroid cancer development among
A-bomb survivors, collection and storage of thyroid tumor samples are indispensable. With introduction of thyroid ultrasound screening to healthexaminations conducted by RERF’s Departmentsof Clinical Studies (Hiroshima and Nagasaki), a
large number of thyroid tumors are now being
detected. It is believed that future collection of as
many thyroid tumor samples as possible, without
regard to radiation dose or distinction between
benign and malignant tumors, would contribute tomechanistic elucidation of thyroid cancer development and radiation carcinogenesis.
In accordance with research protocol (RP) 2-86
“Collection of surgically removed cancer tissues
from A-bomb survivors: Special reference to thyroid and breast cancers,” RERF has worked on collection and cryopreservation of fresh thyroid cancer tissues from A-bomb survivors and nonexposed
controls, with an eye on their use for future molecular biological studies. The present RP, an addendum to the aforementioned RP 2-86, aims at preservation of fresh thyroid tumor tissues surgicallyremoved from the Adult Health Study subjects for
future studies including gene analyses.

Recent Publications(Japanese): the original article is in Japanese.

Abe H, Ochi H, Maekawa T, Hayes CN, Tsuge
M, Miki D, Mitsui F, Hiraga N, Imamura M,
Takahashi S, Ohishi W, Arihiro K, Kubo M,
Nakamura Y, Chayama K: Common variation of
IL28 affects gamma-GTP levels and inflammation of the liver in chronically infected hepatitis
C virus patients. Journal of Hepatology 2010
(September); 53(3):439-43.
Fujiwara S: Importance of raising awareness about
spontaneous insufficiency fractures in the bedridden elderly. International Journal of ClinicalRheumatology 2010 (August); 5(4):395-7.
Fujiwara S, Hamaya E, Goto W, Masunari N,
Furukawa K, Fukunaga M, Nakamura T,
Miyauchi A, Chen P: Vertebral fracture status
and the World Health Organization risk factors
for predicting osteoporotic fracture risk in Japan.
Bone 2011 (June); 49(3):520-5. (RERF Report
4-10)
Grant EJ, Neriishi K, Cologne JB, Eguchi H,
Hayashi T, Geyer SM, Izumi S, Nishi N, Land
CE, Stevens RG, Sharp GB, Nakachi K: Associations of ionizing radiation and breast cancerrelated serum hormone and growth factor levels
in cancer-free female A-bomb survivors. Radiation Research 2011 (June); 176(5):678-87.
(RERF Report 6-10)
Haruta D, Matsuo K, Tsuneto A, Ichimaru S, Hida
A, Sera N, Imaizumi M, Nakashima E, Maemura
K, Akahoshi M: Incidence and prognostic valueof early repolarization pattern in the 12-leadelectrocardiogram. Circulation 2011 (June);
123(25):2931-7. (RERF Report 8-10)
Hashimoto Y, Ochi H, Abe H, Hayashida Y, Tsuge
M, Mitsui F, Hiraga N, Imamura M, Takahashi S,
Nelson Hayes C, Ohishi W, Kubo M, Tsunoda T,
Kamatani N, Nakamura Y, Chayama K: Prediction of response to peginterferon-alfa-2b plus
ribavirin therapy in Japanese patients infectedwith hepatitis C virus genotype 1b. Journal of
Medical Virology 2011 (June); 83(6):981-8.
Hirai Y, Kodama Y, Cullings HM, Miyazawa C,
Nakamura N: Electron spin resonance analysisof tooth enamel does not indicate exposures
to large radiation doses in a large proportionof distally-exposed A-bomb survivors. Journal of Radiation Research 2011 (September);52(5):600-8. (RERF Report 13-10)

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RERF Update Volume 22, Issue 2, 2011

Recent Publications
Horie I, Ando T, Inokuchi N, Mihara Y, Miura S,
Imaizumi M, Usa T, Kinoshita N, Sekine I,
Kamihara S, Eguchi K: First Japanese patient
treated with parathyroid hormone peptide immunization for refractory hypercalcemia caused bymetastatic parathyroid carcinoma. Endocrine
Journal 2010 (April); 57(4):287-92.
Imaizumi M: Radiation and thyroid carcinogenesis.
Geka Chiryo [Surgical Therapy] 2011 (October);105(4):364-9. (Japanese)
Imaizumi M: Thyroid function in Hiroshima andNagasaki atomic-bomb survivors. Kankyo Hormone Gakkai News Letter [Endocrine Disrupter
Newsletter] 2011 (October); 14(2):4. (Japanese)
Kawaoka T, Hayes CN, Ohishi W, Ochi H,
Maekawa T, Abe H, Tsuge M, Mitsui F, Hiraga
N, Imamura M, Takahashi S, Kubo M, Tsunoda
T, Nakamura Y, Kumada H, Chayama K: Predictive value of the IL28B polymorphism on theeffect of interferon therapy in chronic hepatitis C
patients with genotypes 2a and 2b. Journal of
Hepatology 2011 (March); 54(3):408-14.
Kitamura S, Tsuge M, Hatakeyama T, Abe H,
Imamura M, Mori N, Saneto H, Kawaoka T,
Mitsui F, Hiraga N, Takaki S, Kawakami Y,
Aikata H, Takahashi S, Ohishi W, Ochi H, Hayes
CN, Chayama K: Amino acid substitutions incore and NS5A regions of the HCV genome canpredict virological decrease with pegylated interferon plus ribavirin therapy. Antiviral Therapy
2010; 15(8):1087-97.
Nakamura N: Atomic bombs and nuclear power
stations. Chugoku Zeirishi Kaiho [Journal of
Chugoku Certified Public Tax Accountants’
Association] 2011 (July); (No. 570):12-6. (Japanese)
Nakashima E, Fujii Y, Neriishi K, Minamoto A:
Assessment of misclassification in a binary
response: Recovering information on clinicallysignificant cataract prevalence from cataract surgery data in atomic-bomb survivors. Journal of
the Japan Statistical Society 2011; 41(1):17-31.
(RERF Report 14-07)
Ohishi W, Fujiwara S, Cologne JB, Suzuki G,
Akahoshi M, Nishi N, Tsuge M, Chayama K:
Impact of radiation and hepatitis virus infection
on risk of hepatocellular carcinoma. Hepatology
2011 (April); 53(4):1237-45. (RERF Report
7-10)
Ozasa K: Effects of low-dose radiation on the
Return to Table of Contents

38
human body. Igaku Butsuri [Japanese Journal of
Medical Physics] 2011; 31(Suppl 3):41-50. (Proceedings of the Medical Physics Training Session 2011) (Japanese)
Pham TM, Kubo T, Fujino Y, Ozasa K, Matsuda S,
Yoshimura T: Disability-adjusted life years(DALY) for cancer in Japan in 2000. Journal of
Epidemiology 2011 (May); 21(4):309-12.
Stevens RG, Cologne JB, Nakachi K, Grant EJ,
Neriishi K: Body iron stores and breast cancer
risk in female atomic bomb survivors. Cancer
Science 2011 (December); 102(12):2236-40.
(RERF Report 5-11)
Suyama A: A-bomb radiation effects on humanbody. Nagasaki Association for Hibakusha’s
Medical Care (NASHIM), ed. Hibakusha in the
21st Century—Hibakusha in the World and Forefront of Study on Radiation Diseases. Nagasaki:
Nagasaki Press; 2011 (March), pp 118-28. (Japanese)
Suyama A: Children of atomic-bomb survivors.
Nagasaki Association for Hibakusha’s Medical Care (NASHIM), ed. Hibakusha in the 21stCentury—Hibakusha in the World and Forefrontof Study on Radiation Diseases. Nagasaki:
Nagasaki Press; 2011 (March), pp 54-61. (Japanese)
Suzuki G, Yamaguchi I, Ogata H, Sugiyama H,
Yonehara H, Kasagi F, Fujiwara S, Tatsukawa Y,
Mori I, Kimura S: A nation-wide survey onindoor radon from 2007 to 2010 in Japan. Journal of Radiation Research 2010 (November);51(6):683-9.
Takahashi I, Geyer SM, Nishi N, Ohshita T,
Takahashi T, Akahoshi M, Fujiwara S, Kodama
K, Matsumoto M: Lifetime risk of stroke andimpact of hypertension: Estimates from the
Adult Health Study in Hiroshima and Nagasaki.
Hypertension Research 2011 (May); 34(5):64954. (RERF Report 15-09)
Takahashi I, Matsumoto M: Arteriosclerosis: Cytokenes related to aortic calcification. Domyaku
Koka Yobo [Prevention of Arteriosclerosis] 2010
(October); 9(3):113-4. (Japanese)
Yamada M: Follicle stimulation hormone andestragiol levels during perimenopause in acohort of Japanese women: The Radiation
Effects Research Foundation Adult Health Study.
Michalski J, Nowak I, eds. Menopause: Vasomotor Symptoms, Systematic Treatments and
RERF Update Volume 22, Issue 2, 2011

Recent Publications

39

Self-Care Measures. New York: Nova Science
Publishers Inc.; 2010 (April), pp 112-24.
Yamada M, Imaizumi M, Ohishi W: Thyrotropin
levels during the perimenopause: The Radiation
Effects Research Foundation Adult Health Study.
Michalski J, Nowak I, eds. Menopause: Vasomotor Symptoms, Systematic Treatments andSelf-Care Measures. New York: Nova Science
Publishers Inc.; 2010, pp 125-31. (RERF Report
7-09)
Yatsuya H, Toyoshima H, Yamagishi K, Tamakoshi
K, Taguri M, Harada A, Ohashi Y, Kita Y, Naito
Y, Yamada M, Tanabe N, Iso H, Ueshima H;
Japan Arteriosclerosis Longitudinal Study(JALS) group: Body mass index and risk ofstroke and myocardial infarction in a relatively
lean population: Meta-analysis of 16 Japanesecohorts using individual data. Circulation 2010
(September); 3(5):498-505.
Yoshida K, Ohishi W, Nakashima E, Fujiwara S,
Akahoshi M, Kasagi F, Chayama K, Hakoda M,
Kyoizumi S, Nakachi K, Hayashi T, Kusunoki Y:
Lymphocyte subset characterization associatedwith persistent hepatitis C virus infection andsubsequent progression of liver fibrosis. Human
Immunology 2011 (October); 72(10):821-6.
(RERF Report 14-10)

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RERF Update Volume 22, Issue 2, 2011