著者
Takashi Nagai Shunji Yachi Keiya Inao
出版者
Pesticide Science Society of Japan
雑誌
Journal of Pesticide Science (ISSN:1348589X)
巻号頁・発行日
vol.47, no.1, pp.22-29, 2022-02-20 (Released:2022-02-20)
参考文献数
32
被引用文献数
2

We quantitatively evaluated the cumulative ecological risks from multiple pesticides used in paddy fields in Japan. Moreover, we visualized the temporal and regional variability of those risks for 1990–2010. Considering the region-specific parameters of environmental conditions, region-specific predicted environmental concentrations were estimated at 350 river-flow monitoring sites in Japan. Then the multi-substance potentially affected fraction (msPAF) was calculated as a risk index of multiple pesticides by using the computation tool NIAES-CERAP. The median msPAF values for insecticides and herbicides decreased by 92.4% and 53.1%, respectively, from 1990 to 2010. This substantial reduction in ecological risk was attributed to the development of low-risk pesticides by manufacturers, the efforts of farmers in risk reduction, and tighter regulation by the Japanese government. In particular, the substantial reduction of the ecological risk from insecticides was largely due to the decrease in the use of organophosphorus insecticides.
著者
Michio MURAKAMI Takashi NAGAI Michiaki KAI
出版者
The Society for Risk Analysis, Japan
雑誌
リスク学研究 (ISSN:24358428)
巻号頁・発行日
pp.R-22-008, (Released:2022-11-16)
参考文献数
76

Risk analysis approaches involving risk assessment, management, and communication have been developed independently in radiological protection, food safety, and environmental sciences. Summarizing the commonalities and differences in risk analysis methodologies in these fields may contribute to updating future risk analysis. Therefore, this review summarizes the multifaceted perspectives of risk assessment, management, and communication, with actual application examples, by introducing the birth of risk concepts and various risk indicators, and the historical development of risk management and assessment. Particularly, reviewing the relationship of socio-psychological aspects, the importance of ethical and normative perspectives, and the role of dialog with stakeholders is helpful. Based on these reviews, we note that understanding and applying risk indicators across fields is necessary in comparing different types of risk events. Furthermore, we mention that the application of risk assessment that considers egalitarianism and maximin principles will become more important in the future when emphasizing the consideration of ethical and normative perspectives in accordance with the social context and needs from the field. We then discuss the challenges and the need to update the risk analysis for planning and crisis management. We argue that incorporating collaboration with stakeholders can lead to ethically and socially acceptable risk assessment, management and communication.
著者
Koji Ueda Takashi Nagai
出版者
Pesticide Science Society of Japan
雑誌
Journal of Pesticide Science (ISSN:1348589X)
巻号頁・発行日
vol.46, no.3, pp.267-273, 2021-08-20 (Released:2021-08-31)
参考文献数
28
被引用文献数
2

We investigated the relative sensitivity of duckweed Lemna minor and six species of algae to seven herbicides, using an efficient high-throughput microplate-based toxicity assay. First, we assessed the sensitivity of L. minor to the seven herbicides, and then we compared its sensitivity to that of previously published data for six algal species based on EC50 values. For five herbicides, the most sensitive species differed: L. minor was most sensitive to cyclosulfamuron: Raphidocelis subcapitata was most sensitive to pretilachlor and esprocarb: Desmodesmus subspicatus was most sensitive to pyraclonil; and Navicula pelliculosa was most sensitive to pyrazoxyfen. Simetryn was evenly toxic to all species, whereas 2,4-D was evenly less toxic, with only small differences in species sensitivity. These results suggested that a single algal species cannot represent the sensitivity of the primary producer assemblage to a given herbicide. Therefore, to assess the ecological effects of herbicides, aquatic plant and multispecies algal toxicity data sets are essential.
著者
Koji KAWANO Hidekatsu SHIMAKURA Noriyuki NAGATA Yuki MASASHI Akemi SUTO Yukinori SUTO Shohei UTO Hiromichi UENO Takehiro HASEGAWA Takahiro USHIGUSA Takashi NAGAI Yasunori ARAWATARI Kazuki MIYAJI Keitaro OHMORI Takuya MIZUNO
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.15-0457, (Released:2016-05-05)
被引用文献数
14

There have been limited reports on the prevalence of adverse food reactions among dogs suffering from chronic enteropathy (CE) in Japan. We examined the prevalence and histological features of food-responsive enteropathy (FRE) in a total of 32 dogs with history of CE. Fourteen of 18 cases (56.2%) diagnosed as FRE had lymphocytic-plasmacytic enteritis or eosinophilic enteritis by histopathological examination. Characteristic histopathological changes indicating FRE were not identified in 18 cases, though 4 cases did not show any abnormalities. Results collected from this study provided important information that can help to change the way dogs with CE are treated in the future.
著者
Yasuhiro Nakanishi Tatsuma Matsutani Ko Hinokidani Takashi Nagai Mami Irie
出版者
JAPAN SOCIETY OF TROPICAL ECOLOGY
雑誌
Tropics (ISSN:0917415X)
巻号頁・発行日
vol.28, no.4, pp.91-97, 2020-02-01 (Released:2020-02-01)
参考文献数
31
被引用文献数
2

Iron solubilization in mangrove soils associated with polyphenols leached out from leaf-litter can improve iron bioavailability. In this context, the leaf-removing process by mangrove crabs would increase reacting frequency of the polyphenols in mangrove leaves with iron in the soils. In this study, we investigated ecological roles of a leaf-removing crab, Neosarmatium smithi, on the iron solubilization process. After the fallen leaves carried by the crabs to their burrows and eaten by them, polyphenols may be remained in their feces. If so, contact of polyphenols in the feces with mangrove soils could promote elution of dissolved iron from the soils. In order to demonstrate this hypothesis, we firstly surveyed the appearance ratio of the black part in crab burrows and measured total phenolic content in feces of N. smithi as well as in the black part soil. Then, we examined influences of the crab feces on dissolved iron elution from mangrove soils. As the results, the appearance ratio of the black part in the burrow was 67% and the phenolic content in the feces, the black part, and the yellow part in crab burrows were 9.93, 0.49, and 0.12mg g-1, respectively. Dissolved iron content in the solution (soil+water extract from feces) was 0.65μg g-1 and this content was 4.5 times higher than the control (soil+distilled water). We suggest that the polyphenols remained in the feces affect to solubilize insoluble forms of iron by iron reduction and chelating properties.
著者
Norikazu MIYASHITA Yasuaki KUBO Miharu YONAI Kanako KANEYAMA Norio SAITO Ken SAWAI Akira MINAMIHASHI Toshiyuki SUZUKI Toshiyuki KOJIMA Takashi NAGAI
出版者
THE SOCIETY FOR REPRODUCTION AND DEVELOPMENT
雑誌
Journal of Reproduction and Development (ISSN:09168818)
巻号頁・発行日
pp.1108020393-1108020393, (Released:2011-08-05)
被引用文献数
6 13

Dolly, the first mammal cloned from a somatic cell, had shorter telomeres than age-matched controls and died at an early age because of disease. To investigate longevity and lifetime performance in cloned animals, we produced cloned cows with short telomeres using oviductal epithelial cells as donor cells. At 5 years of age, despite the presence of short telomeres, all cloned cows delivered multiple healthy offspring following artificial insemination with conventionally processed spermatozoa from noncloned bulls, and their milk production was comparable to that of donor cows. Moreover, this study revealed that the offspring had normal-length telomeres in their leukocytes and major organs. Thus, cloned animals have normal functional germ lines, and therefore germ line function can completely restore telomere lengths in clone gametes by telomerase activity, resulting in healthy offspring with normal-length telomeres.
著者
Takashi NAGAI Makoto IMAMURA Shuuzou MISUMI Masatomo MORI
出版者
一般社団法人 日本内科学会
雑誌
Internal Medicine (ISSN:09182918)
巻号頁・発行日
vol.41, no.7, pp.566-570, 2002 (Released:2006-03-27)
参考文献数
14
被引用文献数
16 21 16

A 53-year-old woman was admitted because of hypertension and diabetes mellitus. Elevated diastolic blood pressure, hypertensive retinopathy and renal dysfunction indicated malignant hypertension. Adrenocorticotropic hormone (ACTH) and cortisol levels were high although there were no Cushingoid features.One mg dexamethasone administration decreased neither ACTH nor cortisol levels. Brain magnetic resonance imaging revealed a left pituitary tumor (7 mm × 6 mm). Upon removal, the tumor showed positive ACTH staining by immnohistochemistry, and was diagnosed as pituitary ACTH-secreting adenoma (Cushing's disease). Her blood pressure, renal function, blood glucose and hormone levels subsequently improved. Malignant hypertension and deteriorated diabetes mellitus may have been due to subclinical Cushing's disease.(Intrenal Medicine 41: 566-570, 2002)