A review of the Fukushima nuclear reactor accident: radiation effects on the thyroid and strategies for prevention

Purpose of review: This is a summary of the nuclear accident at the Tokyo Electric Power Company Fukushima Daiichi Nuclear Power Stations (FDNPS) on 11 March 2011 to be used as a review of the radiation effects to the thyroid and strategies of prevention.\nRecent findings: The amount of radioiodine released to the environment following the Fukushima accident was 120?Peta Becquerel, which is approximately one-tenth of that in the Chernobyl accident. Residents near the FDNPS were evacuated within a few days and foodstuffs were controlled within 1 or 2 weeks. Therefore, thyroid radiation doses were less than 100?mSv (intervention levels for stable iodine administration) in the majority of children, including less than 1 year olds, living in the evacuation areas. Because the incidence of childhood thyroid cancer increased in those residing near the site following the Chernobyl accident, thyroid screening of all children (0?18 years old) in the Fukushima Prefecture was started. To date, screening of more than 280?000 children has resulted in the diagnosis of thyroid cancer in 90 children (approximate incidence, 313 per million). Thus, although the dose of radiation was much lower, the incidence of thyroid cancer appears to be much higher than that following the Chernobyl accident.\nSummary: A comparison of the thyroidal consequences following the Fukushima and Chernobyl nuclear reactor accidents is discussed. We also summarize the recent increased incidence in thyroid cancer in the Fukushima area following the accident in relation to increased thyroid ultrasound screening and the use of advanced ultrasound techniques

Radiation and Thyroid Diseases : Experiences in Nagasaki and around Chernobyl

The needs of a society are closely related to medical progress and its contribution. For instance, research on AIDS and cancer is carried out to meet the demand of contemporary society. Thyroid disease caused by iodine deficiency is one such challenge, and "radiation and thyroid" is another major research theme. Clinical investigation and basic research on radiation-induced thyroid diseases through molecular epidemiology have received much attention from scientists in Nagasaki because of our historical background of atomic bomb exposure and accumulated data of radiationinduced human diseases. We, therefore, introduce the experiences of thyroid examination in Nagasaki and Chernobyl and epidemiological analysis of the effect of radiation on thyroid diseases

Measurements of Individual Radiation Doses in Residents Living Around the Fukushima Nuclear Power Plant

At the outset of the accident at Fukushima Daiichi Nuclear Power Plant in March 2011, the radiation doses experienced by residents were calculated from the readings at monitoring posts, with several assumptions being made from the point of view of protection and safety. However, health effects should also be estimated by obtaining measurements of the individual radiation doses. The individual external radiation doses, determined by a behavior survey in the "evacuation and deliberate evacuation area" in the first 4 months, were <5 mSv in 97.4% of residents (maximum: 15 mSv). Doses in Fukushima Prefecture were <3 mSv in 99.3% of 386,572 residents analyzed. External doses in Fukushima City determined by personal dosimeters were <1 mSv/3 months (September-November, 2011) in 99.7% of residents (maximum: 2.7 mSv). Thyroid radiation doses, determined in March using a NaI (TI) scintillation survey meter in children in the evacuation and deliberate evacuation area, were <10 mSv in 95.7% of children (maximum: 35 mSv). Therefore, all doses were less than the intervention level of 50 mSv proposed by international organizations. Internal radiation doses determined by cesium-134 (134C) and cesium-137 ( 137C) whole-body counters (WBCs) were <1 mSv in 99% of the residents, and the maximum thyroid equivalent dose by iodine-131 WBCs was 20 mSv. The exploratory committee of the Fukushima Health Management Survey mentions on its website that radiation from the accident is unlikely to be a cause of adverse health effects in the future. In any event, sincere scientific efforts must continue to obtain individual radiation doses that are as accurate as possible. However, observation of the health effects of the radiation doses described above will require reevaluation of the protocol used for determining adverse health effects. The dose-response relationship is crucial, and the aim of the survey should be to collect sufficient data to confirm the presence or absence of radiation health effects. In particular, the schedule of decontamination needs reconsideration. The decontamination map is determined based on the results of airborne monitoring and the radiation dose calculated from readings taken at the monitoring posts at the initial period of the accident. The decontamination protocol should be reevaluated based on the individual doses of the people who desire to live in those areas

Acute Polyradiculoneuropathy Associated With Salmonella Gastroenteritis

We reported a case of acute polyradiculoneuropathy associated with Salmonella gastroenteritis. A68-year-oldman developed progressive motor weakness and areflexia following the febrile illness and diarrhea caused by a strain of Salmonella species O8 group. He showed a rapid and complete recovery from the illness. This is the first report in which Salmonella gastroenteritis might be etiologically related to an acute polyradiculoneuropathy

Immunolocalization of Adhesion Molecules in Rheumatoid and Osteoarthritic Synovial Tissues

To elucidate the potential role of adhesion molecules in the pathogenesis of rheumatoid arthritis (RA), we stained specimens of synovial tissue from patients with RA and osteoarthritis (OA) with monoclonal antibodies against adhesion molecules using an immunohistochemical method. Positive staining with anti-ICAM-1 monoclonal antibody was detected on the synovial lining cells, the sublining cells and the capillary endothelial cells in the synovium from patients with RA, and, to a lesser degree, in that from patients with OA. The capillary endothelial cells from patients with RA intensively expressed both ELAM-1 and VLA-5α molecules, in contrast to that from OA patients. The intensity of both ICAM-1 and ELAM-1 on the capillary endothelial cells in RA synovium was comparable to disease activity and to the degree of synovial proliferation. A high density of expression of LFA-1α , VLA-4α and VLA-5α was observed on the mononuclear cells that infiltrated the RA synovium, especially in the lesions with aggregated mononuclear cells. The findings clearly demonstrated an up-regulation of the expression of adhesion molecules on synovial cells, capillary endothelial cells and infiltrated mononuclear cells in the synovial tissues of patients with RA. This enhanced expression of adhesion molecules may play an important role in the migration of mononuclear cells into the synovial tissues and thus perpetuate the inflammatory response in these tissues

Abnormal Liver Function in Patients with Sjogren\u27s Syndrome

We measured the liver function tests of 145 patients with Sjogren\u27s syndrome (SjS) (75 patients with primary SjS, 70 patients with secondary SjS), and characterized the SjS patients with abnormal liver function tests from several points of view : 1, the incidence of them in the primary SjS comparing with that in secondary SjS. 2, the staining pattern of anti-nuclear antibodies, and 3, the existence of antihepatitis C virus (HCV) antibody, hepatitis B surface (HBs) antigen, and antibody against human T-lymphotropic virus type I (HTLV-I). Abnormal liver function tests were detected in 38 out of 145 patients (26.2%) with SjS. Fifteen of the 38 patients (20.0%) had primary SjS while the remaining patients (32.9%) had secondary SjS. Histopathological examination identified primary biliary cirrhosis (PBC) in 2 patients, autoimmune hepatitis in 4 patients, and autoimmune cholangitis in a single patient with SjS. No significant difference in the presence of antinuclear antibody (ANA) was found between SjS patients with and without abnormal liver function tests. However, the incidence of discrete speckled pattern was significantly higher in SjS patients with abnormal liver function than in the patients with normal liver function. Two sera showing cytoplasmic pattern of ANA were also positive for anti-mitochondrial M2 antibody, allowing the diagnosis of PBC. All 11 sera exhibiting discrete speckled pattern contained significant amounts of anti-centromere antibody. Abnormal liver function tests were detected in 8 of 11 sera with these antibodies, 2 patients with PBC, 2 patients with autoimmune hepatitis, one patient with autoimmune cholangitis, one patient with chronic hepatitis B and 2 other patients with unconfirmed diagnosis. The percentages of anti-HCV antibody-positive, HBs-Agpositive and anti-HTLV-I antibody-positive in sera of patients were higher than those of blood donors from the same geographical area. However, no significant difference was seen of these percentages in sera between the patients with and without abnormal liver function. Taken together, present study indicated that SjS patients with anti-centromere antibody may have some susceptibility for acquiring autoimmune liver disease

Antiphospholipid Antibodies in Patients with Myasthenia Gravis

We measured antiphospholipid antibodies in sera from 94 patients with myasthenia gravis (MG). We found lgG aCL in 14/94 (14.9 % )lgM aCL in 6/94 (6.4 %) and LA in 4/56 (7.1 %) patients with MG. As a whole 21 of 94 (22.3 % ) patients with MG had some aPL. There was no correlation between the presence of aPL and the severity of MGthe presence of hyperplasia of thymustiter of the antiacetylcholine receptor antibodies or anti-single stranded DNA antibodies. Though the percentage of malignant thymoma with aPL were higher than that of malignant thymoma without aPLwe thought that aPL were not the specific antibody in malignant thymoma. In MGaPL did not play as the aCL syndrome and seemed to be non-specific antibodies

Risk for Progression to Overt Hypothyroidism in an Elderly Japanese Population with Subclinical Hypothyroidism

Background: Few population-based studies report the changes with time in thyroid function tests in patients with subclinical hypothyroidism. We compared the risk for developing overt hypothyroidism in patients with subclinical hypothyroidism and euthyroid controls from the same population of elderly Japanese. We also sought associations of selected parameters with the development of overt hypothyroidism in the subclinical hypothyroid and euthyroid groups. Methods: We measured thyrotropin (TSH) and free thyroxine (T4) levels at baseline examinations performed from 2000 to 2003 in the cohort of Japanese atomic-bomb survivors and identified 71 patients with spontaneous subclinical hypothyroidism (normal free T4 and TSH >4.5 mIU/L without a history of thyroid treatment, mean age 70 year) and 562 euthyroid controls. We re-examined TSH and free T4 levels an average of 4.2 years later (range, 1.9-6.9). Results: The risk for progression to overt hypothyroidism was significantly increased in subclinical hypothyroid patients (7.0%) compared with control subjects (1.6%) after adjusting for age and sex (odds ratio, 4.56; p=0.009). Higher baseline TSH levels were associated with progression from subclinical to overt hypothyroidism (p=0.02) in the multivariate analysis, including age, sex, antithyroid peroxidase antibody, and ultrasonography (US) findings. The analysis using binary TSH data suggested that a TSH level >8 mIU/L was a predictive value for development of overt hypothyroidism (p=0.005). On the other hand, serum TSH levels spontaneously normalized in 38 (53.5%) of the patients with subclinical hypothyroidism. In the multivariate analysis, normalization of TSH levels was associated with lower baseline TSH levels (p=0.004) and normal and homogenous thyroid US findings (p=0.04). Atomic-bomb radiation dose was not associated with subclinical hypothyroidism or its course. Conclusions: Subclinical hypothyroidism was four times more likely to be associated with development of overt hypothyroidism than euthyroid controls in the sample population of Japanese elderly. TSH levels in half of the patients normalized spontaneously when assessed after an average follow-up period of 4.2 years. Baseline TSH level and thyroid US findings are potential predictors of future thyroid function in subclinical hypothyroidism