Nobuko Sera

Radiation Effects Research Foundation, Hirosima, Hiroshima, Japan

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Publications (27)114.1 Total impact

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    ABSTRACT: Although ventricular premature contraction (VPC) commonly arises in subjects with and without heart diseases, the prognosis of VPC has remained controversial and the effect of their morphology on mortality has not been fully determined in subjects without obvious heart diseases. The objective of this study was to assess the morphologic effect of VPC on mortality. Japanese atomic bomb survivors (n = 6685) underwent baseline health examinations and standard 12-lead electrocardiogram (ECG) between January 1990 and December 1991. Of these, we extracted data from 5,685 (67.1% women) subjects who had neither heart diseases nor electrocardiographic abnormalities at baseline. Among them, we identified 131 VPC cases using standard 12-lead ECG and classified them into left bundle branch block (LBBB) type (n = 74), right bundle branch block (RBBB) type (n = 21), and undetermined type (n = 36) according to their morphology. These subjects were followed up until December 2008; we compared all-cause, cardiac and coronary heart disease (CHD) mortality rates using multivariate Cox regression analysis between those with and without VPC. No VPCs were associated with all-cause and cardiac mortality, but the LBBB type was significantly associated with CHD mortality (hazard ratio, 2.73; 95% confidence interval, 1.11-6.73) after controlling for age, sex, smoking status, alcohol consumption, and underlying diseases. Among Japanese atomic bomb survivors without obvious heart diseases, LBBB-type VPC was associated with increased CHD mortality. Larger studies are needed to confirm the effect of morphology as it might help to predict the risk. © 2015 Wiley Periodicals, Inc.
    Annals of Noninvasive Electrocardiology 04/2015; DOI:10.1111/anec.12275 · 1.13 Impact Factor
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    ABSTRACT: Few studies have evaluated the association of radiation dose with thyroid nodules among adults exposed to radiation in childhood. To evaluate radiation dose responses on the prevalence of thyroid nodules in atomic bomb survivors exposed in childhood. This survey study investigated 3087 Hiroshima and Nagasaki atomic bomb survivors who were younger than 10 years at exposure and participated in the thyroid study of the Adult Health Study at the Radiation Effects Research Foundation. Thyroid examinations including thyroid ultrasonography were conducted between October 2007 and October 2011, and solid nodules underwent fine-needle aspiration biopsy. Data from 2668 participants (86.4% of the total participants; mean age, 68.2 years; 1213 men; and 1455 women) with known atomic bomb thyroid radiation doses (mean dose, 0.182 Gy; median dose, 0.018 Gy; dose range, 0-4.040 Gy) were analyzed. The prevalence of all thyroid nodules having a diameter of 10 mm or more (consisting of solid nodules [malignant and benign] and cysts), prevalence of small thyroid nodules that were less than 10 mm in diameter detected by ultrasonography, and atomic bomb radiation dose-responses. Thyroid nodules with a diameter of 10 mm or more were identified in 470 participants (17.6%): solid nodules (427 cases [16.0%]), malignant tumors (47 cases [1.8%]), benign nodules (186 cases [7.0%]), and cysts (49 cases [1.8%]), and all were significantly associated with thyroid radiation dose. Excess odds ratios per gray unit were 1.65 (95% CI, 0.89-2.64) for all nodules, 1.72 (95% CI, 0.93-2.75) for solid nodules, 4.40 (95% CI, 1.75-9.97) for malignant tumors, 2.07 (95% CI, 1.16-3.39) for benign nodules, and 1.11 (95% CI, 0.15-3.12) for cysts. The interaction between age at exposure and the dose was significant for the prevalence of all nodules (P = .003) and solid nodules (P < .001), indicating that dose effects were significantly higher with earlier childhood exposure. No interactions were seen for sex, family history of thyroid disease, antithyroid antibodies, or seaweed intake. No dose-response relationships were observed for small (<10-mm diameter) thyroid nodules. Radiation effects on thyroid nodules exist in atomic bomb survivors 62 to 66 years after their exposure in childhood. However, radiation exposure is not associated with small thyroid nodules.
    JAMA Internal Medicine 12/2014; 175(2). DOI:10.1001/jamainternmed.2014.6692 · 13.25 Impact Factor
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    ABSTRACT: We investigated the clinical course of complete right bundle branch block (RBBB) or RBBB with axis deviation (AD) in terms of subsequent pacemaker implantation for high-degree atrioventricular (AV) block or sick sinus syndrome (SSS). Among the 16,170 atomic-bomb survivors in our biennial health examination between July 1967 and December 2010, we detected 520 newly-acquired RBBB subjects with no organic heart disease, and selected 1038 age- (at RBBB diagnosis) and sex-matched subjects without RBBB to serve as comparison subjects. Multivariate Cox regression analysis was used to estimate the hazard ratios (HRs) for the risk of pacemaker implantation due to all causes, AV block or SSS between RBBB and comparison subjects and between RBBB subjects with and without AD. The risk of pacemaker implantation for RBBB was 4.79 (95% confidence interval [CI] 1.89-12.58; P=0.001), 3.77 (95% CI, 1.09-13.07; P=0.036), and 6.28 (95% CI, 1.24-31.73, P=0.026) when implantation was for all causes, AV block and SSS, respectively. RBBB subjects with AD had a higher risk for all-cause pacemaker implantation than subjects without AD (HR, 3.03; 95% CI, 1.00-9.13, P=0.049). RBBB subjects with AD were younger than subjects without AD at the time of RBBB diagnosis (59.4±7.6 vs 74.4±3.1years old, P=0.019), and their progression from diagnosis to pacemaker implantation took longer (15.1±6.6 vs 6.4±3.0years, P=0.032). RBBB, especially with AD, progresses to AV block and SSS that requires pacemaker implantation; the mechanisms by which the conduction defect progresses differ among patients with and without AD.
    International journal of cardiology 03/2014; 174(1). DOI:10.1016/j.ijcard.2014.03.152 · 6.18 Impact Factor
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    ABSTRACT: Atomic bomb (A-bomb) radiation is associated with cardiovascular disease (CVD) and metabolic CVD risk factors. Chronic kidney disease (CKD) is also known to be a risk factor for CVD and little is known whether CKD is associated with A-bomb radiation. To examine whether CKD is associated with CVD risk factors or with A-bomb radiation in A-bomb survivors, we classified renal dysfunction in 1,040 A-bomb survivors who were examined in 2004-2007 as normal [n = 121; estimated glomerular filtration rate (eGFR) ≥90 ml/min/1.73 m(2)]; mild (n = 686; eGFR 60-89 ml/min/1.73 m(2)); moderate (n = 217; eGFR 30-59 ml/min/1.73 m(2)); or severe (n = 16; eGFR <30 ml/min/1.73 m(2)). Also, we diagnosed subjects in the moderate and severe renal dysfunction groups as having CKD (n = 233; eGFR <59 ml/min/1.73 m(2)). After adjusting for age, gender, and smoking and drinking habits, we looked for an association between renal dysfunction and hypertension, diabetes mellitus (DM), hyperlipidemia, and metabolic syndrome (MetS), and between renal dysfunction and A-bomb radiation. Hypertension [odds ratio (OR), 1.57; 95% confidence interval (CI), 1.12-2.20, P = 0.009]; DM (OR, 1.79; 95% CI, 1.23-2.61, P = 0.002); hyperlipidemia (OR, 1.55; 95% CI, 1.12-2.14, P = 0.008); and MetS (OR, 1.86; 95% CI, 1.32-2.63, P < 0.001) were associated with CKD (moderate/severe renal dysfunction), and hyperlipidemia and MetS were also associated with mild renal dysfunction. CKD (OR/Gy, 1.29; 95% CI, 1.01-1.63, P = 0.038) and severe renal dysfunction (OR/Gy, 3.19; 95% CI, 1.63-6.25, P < 0.001) were significantly associated with radiation dose. CKD associated with radiation may have played a role in the development of CVD among A-bomb survivors.
    Radiation Research 11/2012; 179(1). DOI:10.1667/RR2863.1 · 2.45 Impact Factor
  • Masazumi Akahoshi · Nobuko Sera · Eiji Nakashima
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    ABSTRACT: Background: Because red blood cell distribution width (RDW) predicted cardiovascular disease (CVD) mortality, we evaluated the association between RDW and CVD risk factors in hypertensive subjects. Subjects and methods: From 2004 through 2007, 1,040 atomic bomb survivors (405 male) underwent health examination in Nagasaki, Japan. We classified subjects as having hypertension, diabetes mellitus (DM), hyperlipidemia (HLP), metabolic syndrome (MetS), or chronic kidney disease (CKD). We evaluated the association of RDW with CVD risk factors (relating to anthropometric indexes, and lipid and glucose metabolism), estimated glomerular filtration rate (eGFR), pulse wave velocity (PWV) and hematological measurements and compared RDW between controls and hypertensive, DM, HLP, Mets and CKD subjects, respectively. We also compared CVD risk factors, eGFR, PWV, and hematological measurements between hypertensive subjects and controls. Results: RDW were associated positively (P < 0.05) with age, HDL-cholesterol and adiponectin, but negatively (P < 0.05) with waist circumference, BMI, LDL-cholesterol, triglycerides, HOMA-IR, hemoglobin and hematocrit. Hypertensive subjects had deteriorated values of anthropometric indexes, and lipid and glucose metabolism compared to controls. In addition, hypertensive subjects had lower eGFR and higher PWV than controls (P < 0.05). RDW were wider (P < 0.05) in male hypertensives (13.5 +/- 1.1%) than male controls (13.3 +/- 1.3%) but were not different between hypertensive subjects and controls in female. While, RDW were identical between controls and DM, HLP, MetS, and CKD subjects, respectively, in both sexes. Conclusion: RDW was associated with CVD risk factors and hematological measurements and may have impact on CVD in male hypertensive subjects.
    Journal of Hypertension 09/2012; 30:e262. DOI:10.1097/01.hjh.0000420852.64612.fc · 4.22 Impact Factor
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    ABSTRACT: The clinical features of lipid infiltration in the parotid glands (LIPG) have not been studied. Monitoring of atomic-bomb survivors for late effects of radiation exposure has provided the opportunity to review the clinical findings of LIPG. A total of 992 atomic-bomb survivors in Nagasaki, Japan underwent lachrymal and salivary secretion tests and anthropometric, biochemical, and abdominal ultrasonographic examinations between 2002 and 2004. Among 465 subjects who had reduced tear and/or salivary excretion, 176 subjects took a salivary magnetic resonance imaging (MRI) examination. LIPG was detected in 53 of the 176 subjects who had salivary MRI. LIPG cases showed a preponderance of females and fatty liver compared with the subjects without LIPG. Age-and-sex-adjusted regression analysis revealed that body mass index (BMI), low-density lipoprotein cholesterol, triglycerides, hemoglobin A1c, and C-reactive protein were higher, whereas high-density lipoprotein cholesterol and adiponectin were lower, in the subjects with LIPG. Multivariate logistic regression analysis showed that BMI and fatty liver were mutually associated with LIPG independently from radiation dose. LIPG associated with BMI, fatty liver, and coronary risk factors was a clinical manifestation of metabolic syndrome.
    Experimental and Clinical Endocrinology & Diabetes 11/2011; 120(2):110-5. DOI:10.1055/s-0031-1291315 · 1.76 Impact Factor
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    ABSTRACT: 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. 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). 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. 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.
    Thyroid: official journal of the American Thyroid Association 08/2011; 21(11):1177-82. DOI:10.1089/thy.2010.0411 · 3.84 Impact Factor
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    ABSTRACT: Early repolarization pattern is a common ECG finding characterized by J-point elevation and QRS notching or slurring in the inferior and/or lateral leads, yet little is known about its incidence and long-term prognosis in Asian populations. We reviewed all the ECG records of the 5976 atomic-bomb survivors who were examined at least once during our biennial health examination in Nagasaki, Japan, between July 1958 and December 2004. We defined early repolarization pattern as ≥0.1-mV elevation of the J point or ST segment, with notching or slurring in at least 2 inferior and/or lateral leads. We assessed unexpected, cardiac, and all-cause death risk by Cox analysis. We identified 1429 early repolarization pattern cases (779 incident cases) during follow-up, yielding a positive rate of 23.9% and an incidence rate of 715 per 100 000 person-years. Early repolarization pattern had an elevated risk of unexpected death (hazard ratio, 1.83; 95% confidence interval, 1.12 to 2.97; P=0.02) and a decreased risk of cardiac (hazard ratio, 0.75; 95% confidence interval, 0.60 to 0.93; P<0.01) and all-cause (hazard ratio, 0.85; 95% confidence interval, 0.78 to 0.93; P<0.01) death. In addition, both slurring and notching were related to higher risk of unexpected death (hazard ratio, 2.09; 95% confidence interval, 1.06 to 4.12; P=0.03), as was early repolarization pattern manifestation in both inferior and lateral leads (hazard ratio, 2.50; 95% confidence interval, 1.29 to 4.83; P<0.01). Early repolarization pattern is associated with an elevated risk of unexpected death and a decreased risk of cardiac and all-cause death. Specific early repolarization pattern morphologies and location are associated with an adverse prognosis.
    Circulation 06/2011; 123(25):2931-7. DOI:10.1161/CIRCULATIONAHA.110.006460 · 14.95 Impact Factor
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    Annals of the rheumatic diseases 11/2010; 69(11):2056-7. DOI:10.1136/ard.2010.128736 · 10.38 Impact Factor
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    ABSTRACT: A possible association between subclinical hypothyroidism and cardiovascular disease (CVD) has been reported. Monitoring of atomic-bomb survivors for late effects of radiation exposure at the Radiation Effects Research Foundation has provided the opportunity to examine associations between subclinical hypothyroidism and metabolic CVD risk factors. The objective of the study was to evaluate associations between subclinical hypothyroidism and metabolic CVD risk factors, and a cluster of these factors. This was a cross-sectional study of 3549 subjects (mean age 70 years; 1221 men and 2328 women) between 2000 and 2003 comprising 306 subjects with subclinical hypothyroidism and 3243 control euthyroid subjects in Japan. We investigated associations between subclinical hypothyroidism and metabolic CVD risk factors such as hypertension, diabetes mellitus, dyslipidaemia and hyperuricaemia, and a cluster of these factors. Subclinical hypothyroidism was not significantly associated with either hypertension, diabetes mellitus or hyperuricaemia defined by taking into account the use of medications in both men and women, but in men it was associated with dyslipidaemia (P = 0.02). We observed a significantly increased odds ratio (OR) for the presence of three or more metabolic CVD risk factors in men with subclinical hypothyroidism after adjusting for age, body mass index (BMI), and smoking status [OR: 1.83, 95% confidence interval (CI): 1.13-2.94, P = 0.01]. The significant associations remained after an additional adjustment for atomic-bomb radiation dose. There appears to be a significant increase in a cluster of metabolic CVD risk factors among people with subclinical hypothyroidism.
    Clinical Endocrinology 05/2010; 72(5):689-95. DOI:10.1111/j.1365-2265.2009.03697.x · 3.35 Impact Factor
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    ABSTRACT: Although fatty liver predicts ischemic heart disease, the incidence and predictors of fatty liver need examination. The objective of this study was to determine fatty liver incidence and predictive variables. Using abdominal ultrasonography, we followed biennially through 2007 (mean follow-up, 11.6+/-4.6 years) 1635 Nagasaki atomic bomb survivors (606 men) without fatty liver at baseline (November 1990 through October 1992). We examined potential predictive variables with the Cox proportional hazard model and longitudinal trends with the Wilcoxon rank-sum test. In all, 323 (124 men) new fatty liver cases were diagnosed. The incidence was 19.9/1000 person-years (22.3 for men, 18.6 for women) and peaked in the sixth decade of life. After controlling for age, sex, and smoking and drinking habits, obesity (relative risk (RR), 2.93; 95% confidence interval (CI), 2.33-3.69, P<0.001), low high-density lipoprotein-cholesterol (RR, 1.87; 95% CI, 1.42-2.47; P<0.001), hypertriglyceridemia (RR, 2.49; 95% CI, 1.96-3.15; P<0.001), glucose intolerance (RR, 1.51; 95% CI, 1.09-2.10; P=0.013) and hypertension (RR, 1.63; 95% CI, 1.30-2.04; P<0.001) were predictive of fatty liver. In multivariate analysis including all variables, obesity (RR, 2.55; 95% CI, 1.93-3.38; P<0.001), hypertriglyceridemia (RR, 1.92; 95% CI, 1.41-2.62; P<0.001) and hypertension (RR, 1.31; 95% CI, 1.01-1.71; P=0.046) remained predictive. In fatty liver cases, body mass index and serum triglycerides, but not systolic or diastolic blood pressure, increased significantly and steadily up to the time of the diagnosis. Obesity, hypertriglyceridemia and, to a lesser extent, hypertension might serve as predictive variables for fatty liver.
    Hypertension Research 04/2010; 33(6):638-43. DOI:10.1038/hr.2010.45 · 2.94 Impact Factor
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    ABSTRACT: Propylthiouracil (PTU) is known to induce myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) in patients with Graves disease (GD). Previously, we showed that serum MPO-ANCA were frequently seen in patients with GD treated with PTU. In this study, we analyzed 13 patients with positive MPO-ANCA examining a long-term clinical consequence of these patients as well as antibody titers during 5.6 +/- 3.0 years. PTU therapy was continued in 8 patients and discontinued in 5 patients. Antibody titers decreased in 7 of 8 patients who discontinued PTU therapy but remained positive in 5 patients 5 years after PTU withdrawal. The initial MPO-ANCA levels were significantly higher in those antibody titers remained positive for longer than 5 years (n=5) than in those titers turned to be negative within 5 years after PTU withdrawal (n=3) (203 +/- 256 EU and 22 +/- 2 EU, respectively, P=0.04), but there were no significant differences in age, gender, duration of PTU therapy or dosage of PTU. Among 5 patients who continued PTU therapy, 2 patients with initially low MPO-ANCA titers turned to having negative antibody. No patients had new symptoms or signs of vasculitis throughout the follow-up periods. The long-term follow-up study suggests that higher MPO-ANCA levels remain positive for years after PTU withdrawal but are rarely associated with vasculitis.
    Endocrine Journal 10/2009; 57(1):73-9. DOI:10.1507/endocrj.K09E-230 · 2.02 Impact Factor
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    ABSTRACT: Elevated plasma testosterone levels are thought to play a role in the male preponderance of cases of Brugada syndrome (BS) and the development of prostate cancer. The 34 Brugada-like electrocardiogram (ECG) cases were identified among 2,681 male survivors of the atomic bomb who had undergone at least 1 biennial health examination between July 1958 and December 1999 in Nagasaki, Japan. They were followed for incident prostate cancer from July 1958 through December 2004, and the risk of prostate cancer for Brugada-like ECG, age, smoking habit, and radiation exposure was analyzed using Cox proportional hazards analysis. Among the men with or without Brugada-like ECG there were 4 (11.8%) and 54 (2.0%) cases of prostate cancer, respectively. With age adjustment there was a higher risk of prostate cancer for Brugada-like ECG (relative risk (RR): 5.42, 95% confidence interval (CI) 1.96-15.00, P=0.001). With further adjustment for smoking habit and radiation dose, Brugada-like ECG remained a significant risk factor for prostate cancer (RR: 6.47, 95%CI 1.97-21.21, P=0.002). Brugada-like ECG confers a higher risk of prostate cancer independent of age, smoking habit, and radiation exposure. Men with a Brugada-like ECG should be regularly examined for prostate cancer and vice versa, especially elderly subjects.
    Circulation Journal 12/2008; 73(1):63-8. DOI:10.1253/circj.CJ-08-0680 · 3.69 Impact Factor
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    ABSTRACT: The objective of the study was to evaluate the association of thyroid disease with radiation dose in atomic bomb survivors exposed in utero. This was a cross-sectional study. The study was conducted in atomic bomb survivors in Hiroshima and Nagasaki, Japan. Participants included 328 atomic bomb survivors exposed in utero (mean age 55.2 yr, 162 males) who participated in the thyroid study at the Radiation Effects Research Foundation. Examinations were conducted between March 2000 and February 2003. The relationships of various thyroid conditions to atomic bomb radiation dose were measured. Among the 319 participants excluding nine participants whose exposure radiation dose was not estimated, the mean maternal uterine radiation dose was 0.256 Gy. We observed no significant dose-response relationship for the prevalence of solid thyroid nodules (odds ratio at 1 Gy, 2.78; 95% confidence interval 0.50-11.80, P = 0.22), but the risk estimate was similar to the estimate for childhood exposures. The prevalence of cysts and autoimmune thyroid diseases was not associated with radiation dose (P > 0.30). We could not evaluate the dose response for malignant tumors or benign nodules due to the small number of cases. We did not observe a statistically significant linear dose response to radiation for thyroid nodules or autoimmune thyroid diseases 55-58 yr after participants' in utero exposure. However, the risk estimate for solid thyroid nodules was similar for those exposed in utero and those exposed in childhood. Because the study had limited statistical power to detect moderately sized effects, further studies are needed for a definitive conclusion.
    Journal of Clinical Endocrinology &amp Metabolism 06/2008; 93(5):1641-8. DOI:10.1210/jc.2008-0042 · 6.31 Impact Factor
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    ABSTRACT: We examined in the present study the possible involvement of Fas and its ligand (FasL) in the process of Graves' disease. Immunohistochemical analysis showed that few normal thyrocytes expressed Fas but many thyrocytes in Graves' disease expressed this molecule. The percentage of FasL-positive thyrocytes in Graves' thyroids was, however, less than in normal thyroids. Several apoptotic thyrocytes and infiltrating mononuclear cells (MNCs) were detected scattered throughout Graves' thyroid tissues and abundant proliferating cell nuclear antigen (PCNA)-positive thyrocytes were present. Apoptotic cells, as well as PCNA-positive cells, were scarcely detectable in normal thyroid glands, however. In vitro treatment of thyrocytes by IL-1beta a cytokine found to be expressed in Graves' thyroid glands, increased Fas but reduced FasL expression. IL-1beta-stimulated thyrocytes became sensitive to apoptosis by anti-Fas IgM monoclonal antibody (mAb). Activated T cells, which strongly expressed FasL, showed cytotoxic activity toward IL-1beta-stimulated thyrocytes but not toward unstimulated thyrocytes. This cytotoxic activity involved the Fas/FasL pathway. Importantly, unstimulated thyrocytes could kill activated, but not resting, T cells. IL-1beta-stimulated thyrocytes, with down-regulated FasL expression, could not efficiently kill activated T cells. The cytotoxic activity of unstimulated thyrocytes toward activated T cells was inhibited by anti-FasL mAb. Interestingly, unstimulated thyrocytes induced apoptosis in IL-1beta-stimulated thyrocytes but not in unstimulated thyrocytes. These interactions were also blocked by anti-FasL mAb. Our results suggest that the apoptotic cell death of both thyrocytes and infiltrating MNCs found in Graves' thyroid glands is regulated by IL-1beta through Fas/FasL interactions.
    Clinical & Experimental Immunology 06/2001; 124(2):197-207. DOI:10.1046/j.1365-2249.2001.01476.x · 3.28 Impact Factor
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    T Ando · T Usa · A Ide · Y Abe · N Sera · T Tominaga · E Ejima · K Ashizawa · K Nakata · K Eguchi
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    ABSTRACT: A 69-year-old woman with idiopathic thrombocytopenic purpura, who was regularly followed and treated with prednisolone and danazol, was admitted to our hospital because of shortness of breath. Chest roentgenogram showed a large amount of left-sided pleural effusion. Gram-positive branching rods, subsequently identified as Nocardia farcinica, were isolated from the fluid. Antibiotic treatment together with pleural drainage with an intercostal catheter resulted in complete remission of pyothorax. Pulmonary nocardiosis is a rare disease, but recognition of the disease in immunocompromised patients and the prompt initiation of appropriate treatments based on isolation of the pathogen can lead to a successful outcome.
    Internal Medicine 04/2001; 40(3):246-9. DOI:10.2169/internalmedicine.40.246 · 0.97 Impact Factor
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    ABSTRACT: Medullary thyroid carcinoma (MTC) arises from parafollicular or C cells of the thyroid gland and produces a variety of peptides such as calcitonin (CT) and gastrin-releasing peptide (GRP). Here we measured serum levels of pro-gastrin-releasing peptide (Pro-GRP), a more stable precursor of GRP, in 15 patients with MTC (4 males, 11 females) who did not show any clinical or radiologic signs of small cell lung cancer. Serum Pro-GRP levels were elevated in 80% (12/15) patients. Significant correlation was observed between serum Pro-GRP and CT (r = 0.52) and carcinoembryonic antigen (CEA) (r = 0.56). Serum Pro-GRP levels also correlated with tumor size (r = 0.70). Serum Pro-GRP levels also decreased below the cut-off range in one patient after surgical resection. Our data suggest that Pro-GRP, which is considered to be a specific marker for small cell lung carcinoma, seems to be also helpful and additional marker for the diagnosis and monitoring the response to therapy in patients with MTC in addition to calcitonin as the main tumor marker.
    Thyroid 01/2001; 11(11):1055-1061. DOI:10.1089/105072501753271752 · 3.84 Impact Factor
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    ABSTRACT: Thirty-two patients with differentiated thyroid carcinomas with distant metastasis were examined using a radioactive iodine (131I) tracer dose prior to 131I therapy and followed up for 10 years or until death (whichever occurred first). Nineteen patients who received 131I therapy had an accumulation of 131I in the metastases (group I) and 15 of those patients were alive more than 10 years after the first 131I treatment. In contrast, all 13 patients in whom the metastases did not show accumulation of 131I died within 10 years. Of the latter group, eight patients had received 131I therapy (group II), four of whom died with anaplastic changes within 5 years of treatment. p53 gene mutation was identified by immunohistochemistry in primary thyroid carcinoma tissue from patients with anaplastic changes that were evident during total thyroidectomy. Five patients did not receive 131I therapy (group III), of whom one, who also had a p53 gene mutation in the original tumor, died with anaplastic change 10 years after thyroidectomy. Seven patients in group I had p53 gene mutations in their thyroid carcinoma tissues, but none showed anaplastic changes. Our results suggest that 131I therapy may be useful for patients with distant metastases, with or without p53 gene mutations, which show accumulation of 131I from tracer and therapeutic doses. In contrast, 131I therapy is apparently not effective in patients who do not show sufficient accumulation of 131I, but rather, may cause early anaplastic changes with a p53 gene mutation.
    Thyroid 12/2000; 10(11):975-9. DOI:10.1089/thy.2000.10.975 · 3.84 Impact Factor
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    ABSTRACT: Humoral factors produced by activated T cells are thought to be important in the development of bone loss in patients with rheumatoid arthritis (RA). We investigated the inhibitory effect of etidronate disodium (EHDP) on apoptosis of human osteoblasts induced by supernatants from in vitro activated T cell cultures. Human osteoblastic cell line MG63 cells and human primary osteoblast-like cells were used in the present study as human osteoblasts. T cells were incubated with interleukin-2 and further activated with 1 2-o-tetradecanoyl-phorbol 13-acetate and ionomycin, either in the presence or absence of EHDP. After we carried out the cultivation, we examined the cytotoxicity of cultured T cell supernatants toward MG63 cells and human primary osteoblast-like cells. Supernatants from activated but not resting T cell cultures efficiently induced apoptosis of MG63 cells and primary osteoblast-like cells. Supernatants from activated T cell cultures, incubated with EHDP, exhibited significantly less cytotoxicity than did supernatants incubated in the absence of EHDP. In contrast, the cytotoxicity of activated T cell culture supernatants was not affected by direct treatment of human osteoblasts with EHDP. The concentration of soluble Fas ligand in activated T cell culture supernatants was actually increased by EHDP. However, EHDP did not influence soluble Fas and tumor necrosis factor-alpha concentrations in the supernatant. Furthermore, treatment of human osteoblasts with EHDP did not alter their expression of Bcl-2/Bcl-xL or their sensitivity to anti-Fas immunoglobulin M-induced apoptosis. Our results suggest that EHDP inhibits the production of soluble factor that induces apoptosis of human osteoblasts and thus exhibits a protective action toward human osteoblast apoptosis induced by activated T cell culture supernatants. Although the exact EHDP-regulated molecule that induces apoptosis of human osteoblasts is unknown at present, our study may explain part of the therapeutic action of bisphosphonates in RA complicated by bone loss.
    Journal of Laboratory and Clinical Medicine 12/2000; 136(5):344-54. DOI:10.1067/mlc.2000.109757 · 2.80 Impact Factor
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    ABSTRACT: Leptin is a protein product of the ob gene, mainly produced by adipocytes. Leptin is thought to play an important role in the homeostasis of body weight by suppressing appetite and increasing energy consumption. The aim of this study was to investigate the possible effect of thyroid hormone on the regulation of the leptin system during suppression of beta-adrenergic receptors in Graves' patients. We studied 15 adult female patients with Graves' disease. Thyroid function, serum levels of leptin, and percent body fat (%BF) were examined at four different clinical conditions during therapy (A, untreated; B, beta-adrenergic antagonist only [A, B; hyperthyroid], C, beta-adrenergic antagonist and antithyroid drug; D, antithyroid drug only [C, D; euthyroid]). The use of beta-adrenergic antagonist significantly reduced heart rate in spite of hyperthyroid state, indicating sufficient suppression of beta-adrenergic receptors. During treatment with beta-adrenergic antagonist, leptin percentage of body fat (%BF) ratio significantly decreased in euthyroid state compared to that in hyperthyroid state (from 38.7 +/- 21.3 to 18.1 +/- 19.3, p = 0.003). Moreover, there was a significantly positive correlation between delta leptin/%BF and delta free thyroxine (FT4) (r = 0.51, p = 0.008). Under a euthyroid state induced by antithyroid drug treatment, leptin/%BF did not change in spite of withdrawal of beta-adrenergic antagonist. Our data indicate that thyroid hormones could increase serum leptin level during suppression of beta-adrenergic receptors in Graves' patients. Our data also suggest that the beta-adrenergic action of thyroid hormones might be partly mediated by regulation of leptin.
    Thyroid 09/2000; 10(8):641-6. DOI:10.1089/10507250050137707 · 3.84 Impact Factor

Publication Stats

358 Citations
114.10 Total Impact Points

Institutions

  • 2008–2015
    • Radiation Effects Research Foundation
      Hirosima, Hiroshima, Japan
  • 2001–2014
    • Nagasaki University Hospital
      Nagasaki, Nagasaki, Japan
  • 1999–2009
    • Nagasaki University
      • • Department of Endocrinology and Metabolism
      • • School of Medicine
      Nagasaki, Nagasaki, Japan