著者
Suminori Akiba
出版者
日本環境変異原学会
雑誌
Genes and Environment (ISSN:18807046)
巻号頁・発行日
vol.35, no.3, pp.80-87, 2013 (Released:2013-09-03)
参考文献数
52
被引用文献数
1 5

Whether chronic exposure has an cancer risk per dose different from that of acute exposure is a topic of debate. This paper discusses the effect of dose rate on the strength of relationship between cancer risk and external exposure to low-LET (Linear Energy Transfer) ionizing radiation (such as X-rays and gamma rays), by reviewing important epidemiological studies. The study of atomic-bomb survivors, who had acute exposure mainly to low-LET ionizing radiation, has shown that the excess relative risk per gray (ERR/Gy) of leukemia increases in a linear-quadratic manner with an increase of radiation dose. The estimate of ERR/Gy for medium-high dose ranges was shown to be approximately two-fold larger than that for a low-dose range in the atomic-bomb survivor study. The estimate of ERR/Gy associated with acute exposure appears to be larger than those obtained from the studies of low-dose-rate exposure. On the other hand, the risk of solid cancer (or all cancers excluding leukemia) showed a linear dose-response relationship. Regarding the risk modification by dose rates, lower dose-rate exposure to high LET radiation is suspected to be associated with a larger risk. In the case of low-LET exposure, however, the cancer incidence study of residents in high natural background radiation areas of Karunagappally Taluk in Kerala State, India suggests that the ERR per dose for solid cancer after chronic radiation exposure is significantly lower than that associated with acute exposure such as that experienced by atomic-bomb survivors.
著者
Takashi Kihara Sadatoshi Biro Yoshiyuki Ikeda Tsuyoshi Fukudome Takuro Shinsato Akinori Masuda Masaaki Miyata Shuichi Hamasaki Yutaka Otsuji Shinichi Minagoe Suminori Akiba Chuwa Tei
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.68, no.12, pp.1146-1151, 2004 (Released:2004-11-25)
参考文献数
47
被引用文献数
64 105

Background The aim of the present study was to determine whether repeated 60C sauna treatment improves cardiac arrhythmias in chronic heart failure (CHF) patients, because ventricular arrhythmias are an important therapeutic target in CHF. Methods and Results Thirty patients (59±3 years) with New York Heart Association functional class II or III CHF and at least 200 premature ventricular contractions (PVCs)/24 h assessed by 24-h Holter recordings were studied. They were randomized into sauna-treated (n=20) or non-treated (n=10) groups. The sauna-treated group underwent a 2-week program of a daily 60°C far infrared-ray dry sauna for 15 min, followed by 30 min bed rest with blankets, for 5 days per week. Patients in the non-treated group had bed rest in a temperature-controlled room (24°C) for 45 min. The total numbers of PVCs/24 h in the sauna-treated group decreased compared with the non-treated group [848±415 vs 3,097±1,033/24 h, p<0.01]. Heart rate variability (SDNN, standard deviation of normal-to-normal beat interval) increased [142±10 (n=16) vs 112±11 ms (n=8), p<0.05] and plasma brain natriuretic peptide concentrations decreased [229±54 vs 419±110 pg/ml, p<0.05] in the sauna-treated group compared with the non-treated group. Conclusion Repeated sauna treatment improves ventricular arrhythmias in patients with CHF. (Circ J 2004; 68: 1146 - 1151)
著者
Yoshihide Kinjo Valerie Beral Suminori Akiba Tim Key Shoichi Mizuno Paul Appleby Naohito Yamaguchi Shaw Watanabe Richard Doll
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.9, no.4, pp.268-274, 1999 (Released:2007-11-30)
参考文献数
29
被引用文献数
46 58

Cerebrovascular disease was a leading cause of death from 1955 to 1980 in Japan. The mortality rate from this disease has decreased sharply in recent decades. This downward trend seems to correspond to the dietary habits of Japanese. Data from a large prospective cohort study were analyzed to examine the association between dietary habits and cerebrovascular disease mortality in Japan. The subjects for this analysis were 223, 170 men and women aged 40 to 69 at baseline in December 1965. There were 6, 168 deaths in men and 4, 862 deaths in women due to cerebrovascular disease (ICD7: 330-334) during the follow-up period from January 1966 to December 1981. Rate ratio (RR) and 95% confidence interval (95%Cl) adjusted for sex, attained age, follow-up period, prefecture, cigarette smoking, alcohol drinking and occupation was used for comparison. In this study, the risk of mortality from cerebrovascular disease was inversely associated with dairy milk, meat and fish consumption. Therefore the joint effect of dairy milk, meat and fish (DMF) as animal fat and protein was of interest. In the binary analysis, DMF (D, M, F) means the combination of dairy milk (1-3 times/week or more), meat (1-3 times/week or more) and fish (4 times/week or more). Thus DMF (d, m, f) was the reference group having dairy milk (less than 1 time/week), meat (less than 1 time/week) and fish (less than 4 times/week). For the disease, the RR of DMF (D, M, F) was 0.68 with 95%CI of 0.63 to 0.74, relative to the reference group. Furthermore the joint effect of DMF was more strongly associated with cerebral haemorrhage (ICD7: 331, DMF (D, M, F); RR: 0.63, 95%Cl: 0.55-0.70) than with cerebral embolism and thrombosis (ICD7: 332, DMF (D, M, F); RR: 0.79, 95%Cl: 0.70- 0.89). These findings suggest that the increasing intake of animal fat and/or protein may have played a key role in reducing cerebrovascular disease in Japan. J Epidemiol, 1999 ; 9 : 268-274.
著者
Yoshihide Kinjo Suminori Akiba Naohito Yamguchi Shoichi Mizuno Shaw Watanabe Junji Wakamiya Makoto Futatsuka Hiroo Kato
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.6, no.3, pp.134-138, 1996 (Released:2007-11-30)
参考文献数
24
被引用文献数
5 13

We report here a historical cohort study on cancer mortality among Minamata disease (MD) patients (n=1, 351) in Kagoshima and Kumamoto Prefectures of Japan. Taking into account their living area, sex, age and fish eating habits, the residents (n=5, 667; 40 years of age or over at 1966) living in coastal areas of Kagoshima, who consumed fish daily, were selected as a reference group from the six-prefecture cohort study conducted by Hirayama et al. The observation periods of the MD patients and of the reference group were from 1973 to 1984 and from 1970 to 1981, respectively. Survival analysis using the Poisson regression model was applied for comparison of mortality between the MD patients and the reference group. No excess of relative risk (RR) adjusted for attained age, sex and follow-up period was observed for mortality from all causes, all cancers, and non-cancers combined. Analysis of site-specific cancers showed a statistically significant decrease in mortality from stomach cancer among MD patients (RR, 0.49; 95 % confidence interval, 0.26-0.94). In addition, a statistically significant eight-fold excess risk, based on 5 observed deaths, was noted for mortality from leukemia (RR, 8.35; 95 % confidence interval, 1.61-43.3). It is, however, unlikely for these observed risks to be derived from methylmercury exposure only. Further studies are needed to understand the mechanisms involved in the observed risks among MD patients. J Epidemiol, 1996 ; 6 : 134-138.
著者
JIANMING ZOU QUANFU SUN SUMINORI AKIBA YONGLING YUAN YONGRU ZHA ZUFAN TAO LUXIN WEI TSUTOMU SUGAHARA
出版者
Journal of Radiation Research 編集委員会
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.41, no.SUPPL, pp.S53-S62, 2000 (Released:2001-10-19)
参考文献数
17
被引用文献数
41

The main purposes of this study were to identify the major determinants of nasopharyngeal carcinoma (NPC) in the high-background radiation areas (HBRA) in Yangjiang, China and to evaluate their potential confounding effects on the NPC risk associated with exposure to high background radiation. A matched case-control study was conducted using those who died of NPC during the period 1987-1995. Two controls were randomly selected for each case from those who died from causes other than malignancies and external causes. Cases and their controls were matched with respect to sex and the years of birth and death (±5 years). Study subjects' next-of-kin were interviewed using a standardized questionnaire to collect information on socioeconomic status, dietary habits, tobacco smoking and alcohol consumption, disease history, pesticide use, medical X-ray exposure, the family history of NPC and so on. We succeeded in interviewing 97 cases and 192 controls. Univariate conditional logistic regression analysis showed that NPC risk was associated with the consumption of salted fish, homemade pickles, and fermented soy beans, education levels, the history of chronic rhinitis, and the family history of NPC. Multivariate conditional logistic regression analysis revealed that education levels (Odds ratio (OR) for middle school or higher levels vs. no school education=3.8, 95% CI=1.2 to 11.8), salted fish intake (OR=3.2, 95% CI=1.7 to 6.1), the history of chronic rhinitis (OR=3.6, 95% CI=1.3 to 10.1), and the family history of NPC (OR=14.2, 95% CI=2.7 to 73.4) were independent risk factors of NPC. Tobacco smoking (OR=1.2, 95% CI=0.7 to 2.1), and alcohol consumption (OR=0.9, 95% CI=0.5 to 1.9) were not significantly related to NPC risk. The ORs of NPC risk comparing HBRA and a nearby control area before and after adjustment for the major risk determinants identified in the present study were 0.86 (95% CI=0.50 to 1.50) and 0.87 (95% CI=0.45 to 1.67), respectively. Salted fish intake was a strong risk factor of NPC. Education, the history of chronic rhinitis and the family history of NPC were also related to NPC risk. The exposure to high background radiation in HBRA of Yangjiang was not related to NPC risk with or without the adjustment for those major risk determinants of NPC.
著者
QUANFU SUN SUMINORI AKIBA ZUFAN TAO YONGLING YUAN JIANMING ZOU HIROSHIGE MORISHIMA HIROO KATO YONGRU ZHA TSUTOMU SUGAHARA LUXIN WEI
出版者
Journal of Radiation Research Editorial Committee
雑誌
Journal of Radiation Research (ISSN:04493060)
巻号頁・発行日
vol.41, no.SUPPL, pp.S43-S52, 2000 (Released:2001-10-19)
参考文献数
18
被引用文献数
19

A study was made on cancer mortality in the high-background radiation areas of Yangjiang, China. Based on hamlet-specific environmental doses and sex- and age-specific occupancy factors, cumulative doses were calculated for each subject. In this article, we describe how the indirect estimation was made on individual dose and the methodology used to estimate radiation risk. Then, assuming a linear dose response relationship and using cancer mortality data for the period 1979-1995, we estimate the excess relative risk per Sievert for solid cancer to be -0.11 (95% CI, -0.67, 0.69). Also, we estimate the excess relative risks of four leading cancers in the study areas, i.e., cancers of the liver, nasopharynx, lung and stomach. In addition, we evaluate the effects of possible bias on our risk estimation.