巻号一覧
57 巻 (2002 - 2003)
- 4 号 p. 615-
- 3 号 p. 547-
- 2 号 p. 475-
57 巻, 4 号
選択された号の論文の8件中1～8を表示しています
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(3)実験動物および培養細胞における毒性佐藤 雅彦, 鍜冶 利幸, 遠山 千春2003 年 57 巻 4 号 p. 615-623
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーWe have reviewed studies on cadmium (Cd) toxicity in laboratory animals and cultured cells with special attention to the disruption in cellular signal transduction, involvement in apoptosis of Cd, the cellular transport system for Cd and roles of metallothionein as a protective factor against Cd. Cd affects cellular functions by perturbing signal transductions, such as protein kinase C, mitogen-activated protein kinase and cyclic AMP pathways, but how the disruption of these pathways by Cd leads to the manifestation of toxicity in vivo is largely unknown. Exposure to cadmium at relatively high and low levels causes necrosis and apoptosis, respectively, which suggests that the mode of cell death by cadmium is dependent upon its exposure level. On the other hand, utilization of Ca2+ channels, DMT1 (divalent metal transporter 1) and a novel transport system having high-affinity for Mn2+ and Cd2+ were found to act as Cd transport systems via the cellular membrane. Metallothionein-I/II-null mice are highly susceptible to renal toxicity, hepatotoxicity, bone injury, hematotoxicity and immunotoxicity caused by chronic Cd exposure. Thus, metallothionein plays an important role in detoxification of Cd toxicity.抄録全体を表示PDF形式でダウンロード (1582K) -
(4)生体負荷量・臨界濃度・生命予後小山 洋, 佐藤 雅彦, 遠山 千春2003 年 57 巻 4 号 p. 624-635
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーAs the last manuscript in our series of review articles on cadmium (Cd) and health effects, we reviewed research articles on epidemiologic and experimental studies on exposure levels of Cd in occupational and environmental settings in various countries, disposition and body burden of Cd, critical concentrations of Cd in the kidney of humans and animals with a focus on biomarkers for renal dysfunction, and life expectancy in Cd-polluted areas and reference areas. After this manuscript was compiled, cadmium levels in rice crops received significant attention, since the risk assessment of cadmium is now under review and discussion by the Joint Expert Committee of Food Additives and Contaminants organized by the Food Agricultural Organization and World Health Organization in 2003. We hope that the information compiled in this review may provide directions for future studies on the health risk assessment of Cd.抄録全体を表示PDF形式でダウンロード (2261K) -
内外の文献検索を行って倉橋 典絵, 岸 玲子2003 年 57 巻 4 号 p. 636-644
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーRecently, it has been reported that the incidence of male genitourinary abnormalities (such as cryptorchidism) has been increasing because of the presence of endocrine-disrupting chemicals (EDCs) in the environment. This report reviews the papers related to cryptorchidism beginning in the 1960s to clarify the trends in incidence of cryptorchidism and to discuss the association between cryptorchidism and risk factors, including EDCs.
The incidence of cryptorchidism tended to increase in almost researched countries until the mid-1980s, but has shown regional differences since 1990. In Japan, the trend of the incidence of cryptorchidism is unclear because there is no monitoring system for cryptorchidism.
It is necessary to establish both criteria and a monitoring system to research the incidence of cryptorchidism. The risk factors in epidemiological studies include low birth weight, being small for gestational age, a short gestation period, high maternal body weight, the change during pregnancy of maternal hormones (by exposure to diethylstilbestrol DES or estrogen), and exposure to chemicals. However, the associations between children with cryptorchidism and exposure to EDCs as well as between cryptorchidism and exposure to estrogen of the fetus are not clear because very few reports have quantatively evaluated EDCs. It is known that some EDCs act as estrogen receptor agonists and change hormonal mobility as exogenous estrogen. It has also been suggested that hormonal drugs such as DES affect the maternal endocrine system in pregnancy and are associated with the incidence of cryptorchidism. In the future, epidemiological studies that clarify the association between cryptorchidism and EDCs such as daidzein and genistein and the quantative evaluation of exposure factors using biological materials are necessary.抄録全体を表示PDF形式でダウンロード (1401K) -
紺野 信弘2003 年 57 巻 4 号 p. 645-654
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーThe neurotoxicity of organophosphorus compounds (OPs) including leptophos, TOCP and triphenyl phosphite and dithiocarbamate compounds were reviewed in this study. The major neurotoxicities of OPs were acute toxicity produced by the acetylcholine esterase (AChE) inhibiting action of OPs and delayed neurotoxicity produced by such OPs as leptophos and TOCP. The direct action of OP on the muscarinic and/or nicotinic acethylcholine receptors in the synaptic membranes have lately attracted attention in relation to acute toxicity. Delayed neurotoxicity is a delayed onset of prolonged locomotor ataxia resulting from a single or repeated exposure to an OP. Although neurotoxic esterase (NTE) inhibition might be related to the onset of organophosphate-induced delayed neurotoxicity (OPIDN), the precise mode of action is not yet clear.
The effect of dithiocarbamates on the nervous system is also mentioned, because the compounds are currently suspected not only for neurotoxicity, but also as endocrine-disrupting chemicals. Although dithiocarbamates showed weak neurotoxicity in adult animals, we need to pay more attention to developmental neurotoxicity.抄録全体を表示PDF形式でダウンロード (3817K) -
西尾 尚美, 藤岡 洋成, 緑川 泰史, 石崎 香理, 町田 和彦2003 年 57 巻 4 号 p. 655-660
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーObjectives: In order to clarify the relation between stress load and inoculated tumor growth in conjunction with neutrophil functions, several kinds of stress such as physical (Ph) and psychological (Ps) stress were loaded on rats either SST-2 tumor cell inoculated or control, and the functions of their peripheral neutrophils were determined.
Methods: A communication box was used for stress load on rats. SST-2 cells were inoculated in to rats in the tumor-inoculation groups. Two weeks after inoculation, the tumors were removed from the backs of the rats and weighed. The functions of neutrophils in the peripheral blood collected from the tail vein, were determined by the NBT deoxidization method.
Results: Tumor growth was enhanced when rats were loaded with either Ph or Ps stresses, but was inhibited when tumor cells were inoculated following either Ph or Ps stresses. These results show that chronological differences of loaded stresses influence immunological functions differently. The O2- production from the neutrophils stimulated by NBT-treated Staphilococcus aureus was suppressed in tumor-inoculated Ph and Ps groups, more markedly in the tumor-inoculated Ph group. It is logically relevant that the size of tumors increased in these groups, predominantly in the tumor-inoculated Ph group. On the other hand, O2- production from the neutrophils was enhanced and tumor growth decreased in tumor-inoculated animals following either Ph or Ps stresses.
Conclusions: Our experiments, it revealed that the function of neutrophils is strongly enhanced by stress load and O2- production is inhibited by the tumor inoculation as shown in stimulation tests. Therefore, our findings suggested that neutrophils may participate in the inhibition of tumor growth.抄録全体を表示PDF形式でダウンロード (1057K) -
沖縄県と佐賀県の比較高倉 実, 栗原 淳, 堤 公一2003 年 57 巻 4 号 p. 661-668
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーObjectives: This study aims to examine regional differences in relationships between depressive symptoms and psychosocial factors among Japanese high school students in Okinawa and Saga prefectures in Japan.
Methods: The study sample was 3, 234 students from 14 public high schools in Okinawa and 2, 503 students from 12 public high schools in Saga. The students completed a self administered questionnaire between September and November 2000. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale (CES-D). The psychosocial factors examined were participation in community events, life stress, self-esteem, perceived social support, and life environment.
Results: There was no difference in depressive symptoms by region. Students in Saga had higher levels of stress in the academic, teachers' and friends' domains compared to students in Okinawa. Students in Saga also evaluated their natural environment better than their counterparts in Okinawa. On the other hand, students in Okinawa were more likely to participate in community events than those in Saga. After controlling for sociodemographic variables, depressive symptoms were found to be significantly associated with life stress, self-esteem, and social support among students in both Okinawa and Saga. Only among students in Okinawa, however, were depressive symptoms significantly related to participation in community events. The psychosocial factors accounted for the same amount of variance in depressive symptoms for Okinawa and Saga students. Additionally, life stress in the teachers' domain had stronger associations with depressive symptoms among students in Saga than among those in Okinawa. The depressive symptom levels of Okinawa students seemed to be more strongly associated with self-esteem than those affecting their counterparts in the Saga prefecture.
Conclusion: These findings show that there is similar pattern of associations between depressive symptoms and psychosocial factors among high school students in Okinawa and Saga, except for participation in community events. Life stress, self-esteem, and social support may be common factors associated with depressive symptoms among high school students regardless of region. Overall, the magnitude of the relationship between depressive symptoms and psychosocial factors was similar across Okinawa and Saga students.抄録全体を表示PDF形式でダウンロード (1384K) -
NIPPON DATA80川南 勝彦, 簑輪 眞澄, 岡山 明, 早川 岳人, 上島 弘嗣, ＮＩＰＰＯＮ ＤＡＴＡ８０研究グループ2003 年 57 巻 4 号 p. 669-673
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーObjectives: The authors examined the relationship and the population attributable fraction (PAF) between smoking habit and death from all causes, including cancer and lung cancer.
Methods: The baseline data were collected in the National Cardiovascular Survey in 1980 carried out for all household members aged 30 years or older in 300 districts, which were randomly selected throughout Japan. The number of participants in the survey was 10, 546. The vital status was ascertained in 1999, and he calculated the adjusted relative risk of mortality and the PAF of mortality attributable to stopping smoking.
Results: A total of 9, 629 subjects were available for the final analyses. There were 165, 190 personyears of follow-up, and 2, 011 deaths from all causes, including 579 deaths from cancer and 106 deaths from lung cancer. After adjustment for age and other cancer risk factors, smoking habit was associated with mortality from all causes, cancer and lung cancer. These associations had positive trends.
The PAF (%) from all causes was 9.0 (male), 1.6 (female). The PAF (%) from cancer was 29.5 (male), 2.7 (female) and that from lung cancer was 42.9 (male), 7.1 (female).
Conclusions: After adjustment for age and other cancer risk factors, smoking habit was associated with mortality from all causes, cancer and lung cancer. These associations had positive trends.
The PAF (%) from all causes was 9.0 (male), 1.6 (female). The PAF (%) from cancer was 29.5 (male), 2.7 (female) and that from lung cancer was 42.9 (male), 7.1 (female).抄録全体を表示PDF形式でダウンロード (747K) -
松嶋 紀子, 森田 徳子, 尾方 希, 佐伯 圭吾, 松田 亮三, 車谷 典男2003 年 57 巻 4 号 p. 674-681
発行日: 2003/01/15
公開日: 2009/02/17
ジャーナル フリーObjectives: To investigate the diurnal rhythm of live births labored spontaneously, and the effects of obstetric intervention on birth time distributions.
Methods: The data of live births tabulated by time (one-hour intervals), date and birthplace throughout Japan between 1981 and 1998 were obtained with permission from the former Ministry of Health and Welfare. Together with an investigation of hourly birth numbers by place in each year, an annual transition of hourly birth rates in medical institutions and the diurnal rhythm of birth numbers in maternity homes and at home were analyzed using regression analysis.
Results: In every calendar year studied the hourly live birth numbers at hospitals showed a singlepeak distribution pattern with maximum values at 13:00-15:00. The annual transition of hourly birth rates showed a 10% (birth numbers base) decrease in the 11:00-13:00 period in 1998 as compared with that in 1981, while there was a corresponding increase of 8% in the 13:00-15:00 period. Hourly birth numbers at clinics showed a double-peak distribution pattern with maximum values during the 11:00-12:00 and 14:00-15:00 periods in early 1980, while a single-peak distribution with a maximum value during the 13:00-15:00 period appeared in 1989 and has remained thereafter. Hourly birth rates (birth numbers base) increased by over 6% in the 13:00-15:00 and 17:00-20:00 periods over the past 18 years, while they decreased by 10% in the 9:00-13:00 period. The results at maternity homes were clearly different from those at hospitals and clinics. The live birth numbers totaled for the 18 years showed a double-phase distribution with a maximum value in the 6:00-7:00 period and a minimum value in the 19:00-20:00 period. The best-fit regression model for the obtained data was a sine curve with a maximum value at 6:00 (coefficient of determination 0.97). Hourly distributions of live births at home also fitted best to a sine curve with the maximum value again at 6:00 (coefficient of determination 0.95).
Conclusions: The results suggested that the timing of spontaneous live births follows a circadian rhythm and that obstetric intervention affects time distributions of live births by shifting over 10% of births during the night and early morning to a working day service time (9:00-17:00).抄録全体を表示PDF形式でダウンロード (1427K)
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