著者
Yoshio Tsuda Yoshihide Maekawa Kohei Ogawa Kentaro Itokawa Osamu Komagata Toshinori Sasaki Haruhiko Isawa Takashi Tomita Kyoko Sawabe
出版者
国立感染症研究所 Japanese Journal of Infectious Diseases 編集委員会
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
pp.JJID.2014.576, (Released:2015-03-13)
参考文献数
27
被引用文献数
4 48

A total of 160 autochthonous dengue cases transmitted by Aedes albopictus were reported from August to October 2014 in Tokyo Metropolis, Japan. Ae. albopictus is a medically important vector of dengue virus which has been expanding its geographic distribution in temperate regions. The understanding of the distribution and density of biting Ae. albopictus during the dengue outbreak case in Tokyo 2014 is valuable and important to evaluate the epidemic-risk of dengue fever in other highly populated cities in Europe. Of the 160 cases, 134 patients had visited a same park located in central Tokyo, Yoyogi Park. Mosquitoes infected with dengue virus were collected from this park suggesting that the place was the exclusive center of dengue transmission. This study aimed to collect referential data to estimate the transmission threshold of dengue virus in terms of biting density of Ae. albopictus and demonstrated high transmission-risk areas of dengue virus in Yoyogi Park and the vicinity. The overall mean density of biting Ae. albopictus, 7.13/man/8 min, was sufficiently high for successful transmission of dengue virus, and areas with biting densities higher than the overall mean density were classified as high transmission-risk areas of dengue virus in Yoyogi Park.
著者
Kohei Ogawa Naho Morisaki Aurelie Piedvache Chie Nagata Haruhiko Sago Kevin Y. Urayama Kazuhiko Arima Takayuki Nishimura Kiyomi Sakata Kozo Tanno Kazumasa Yamagishi Hiroyasu Iso Nobufumi Yasuda Tadahiro Kato Isao Saito Atsushi Goto Taichi Shimazu Taiki Yamaji Motoki Iwasaki Manami Inoue Norie Sawada Shoichiro Tsugane
出版者
Japan Epidemiological Association
雑誌
Journal of Epidemiology (ISSN:09175040)
巻号頁・発行日
vol.32, no.4, pp.168-173, 2022-04-05 (Released:2022-04-05)
参考文献数
33
被引用文献数
6

Background: Although prevalence of low birth weight has increased in the last 3 decades in Japan, no studies in Japanese women have investigated whether birth weight is associated with the risk of pregnancy complications, such as pregnancy-induced hypertension (PIH) and gestational diabetes mellitus (GDM).Methods: We used data from the Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT), a population-based cohort study in Japan that launched in 2011. In the main analysis, we included 46,365 women who had been pregnant at least once, for whom information on birth weight and events during their pregnancy was obtained using a self-administered questionnaire. Women were divided into five categories according to their birth weight, and the relationship between birth weight and risk of PIH and GDM was examined using multilevel logistic regression analyses with place of residence as a random effect.Results: Compared to women born with birth weight of 3,000–3,999 grams, the risk of PIH was significantly higher among women born <1,500 grams (adjusted odd ratio [aOR] 1.60; 95% confidence interval [CI], 1.17–2.21), 1,500–2,499 grams (aOR 1.16; 95% CI, 1.03–1.30), and 2,500–2,999 grams (aOR 1.13; 95% CI, 1.04–1.22). The risk of GDM was significantly higher among women born 1,500–2,499 grams (aOR 1.20; 95% CI, 1.02–1.42), albeit non-significant association among women in other birthweight categories.Conclusions: We observed an increased risk of PIH among women born with lower birth weight albeit non-significant increased risk of GDM among Japanese women.
著者
Katsunori Yamaura Kohei Ogawa Taeko Yonekawa Tomonori Nakamura Shingo Yano Koichi Ueno
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.25, no.2, pp.201-205, 2002 (Released:2002-04-27)
参考文献数
44
被引用文献数
10 18

The causal relationship between the inhibition of antibody production and liver injury induced by single doses of acetaminophen (APAP) was investigated in mice. The liver injury and antibody production were evaluated using the serum transaminase activity and the number of antibody forming cells against sheep red blood cells (SRBC), respectively. The relevance of APAP hepatotoxicity with inhibiting antibody production was elucidated in fasted and fed mice treated with a single oral administration of APAP. In fasted mice, the oral administration of APAP produced serious liver injury, while it was not the case in the fed mice. As the antibody production was measured under these conditions, APAP significantly depressed the antibody production in fed mice as well as in fasted mice. The rate of B220 positive cells in the splenocytes was significantly decreased by APAP administration in both the fasted and fed mice. Splenocytes proliferative responses following mitogenic stimulation with concanavalin A or lipopolysaccharide were inhibited by APAP. Moreover, APAP added directly to the splenocyte culture also inhibited the in vitro antibody-producing response to SRBC. These findings indicate that the APAP-induced depression of antibody production may not be a secondary response to APAP-hepatitis, but may be a primary response to APAP.
著者
Kohei Ogawa Osamu Komagata Toshihiko Hayashi Kentaro Itokawa Shigeru Morikawa Kyoko Sawabe Takashi Tomita
出版者
国立感染症研究所 Japanese Journal of Infectious Diseases 編集委員会
雑誌
Japanese Journal of Infectious Diseases (ISSN:13446304)
巻号頁・発行日
pp.JJID.2015.038, (Released:2015-06-12)
参考文献数
21
被引用文献数
8

The objective of this study was to clarify the efficacy of a currently-available DEET repellent against tick species in Japan. We performed two different field trials: “human trap,” and “flag-dragging.” In total, 482 ticks were collected from white flannel cloths in field studies. The species of collected ticks consisted of Ixodes persulcatus and I. ovatus which accounted for 5.3 and 94.7% in the human trap test and 31.4 and 68.6% in the flag-dragging test, respectively. The repellency levels of DEET-treated flannel cloths in the human trap and flag-dragging tests were 84.0 and 99.7%, respectively. The escape time of I. persulcatus and I. ovatus female adults from DEET-treated flannel cloth was measured. Median escape times for I. persulcatus and I. ovatus on DEET-treated flannel cloth were 48 s (95% CI: 30–96) and 10 s (95% CI: 5–24), respectively. In contrast, many ticks remained on untreated flannel for 10 min after mounting. These results indicate that DEET repellents appear to prevent tick bites and that the use of DEET repellents against ticks is effective as a personal protective measure.
著者
Mayu Kuroki Shinichi Ookawara Kohei Ogawa
出版者
The Society of Chemical Engineers, Japan
雑誌
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN (ISSN:00219592)
巻号頁・発行日
vol.42, no.Supplement., pp.s73-s78, 2009-12-30 (Released:2009-12-30)
参考文献数
18
被引用文献数
39 56

A novel high-fidelity CFD model is proposed for the process optimization and intensification of methane steam reforming in a packed bed reactor. The random packing of spherical particles is constituted by simulating a dumping of particles into the annular reactor by a commercial code based on discrete element method (DEM). The complex spatial geometry between hundreds of particles is created associated with a developed interparticle bridge method, which eliminates the interparticle and particle–wall contact regions by assuming that the small regions are stagnant and would not affect the reactor behavior. The conservation equations of mass, momentum, energy and chemical species are fully solved by employing a commercial CFD code based on finite volume method. A newly coded subroutine is incorporated into the CFD code to evaluate the reaction rates according to the species partial pressures and temperature on each surface cell covering the particles. The values of reaction, equilibrium and adsorption constants are specified based on the experiments in the literature. According to the reaction rates, the mass and heat sources are given to each fluid cell on the surface cell. It is verified that the developed CFD model is capable of predicting the distributions of species and temperature microscopically as well as macroscopically for methane steam reforming. The present DEM–CFD procedure enables one to investigate the behavior of packed bed reactor in detail once the catalyst is characterized in a conventional way. Therefore it would become a powerful tool to optimize and intensify any process in a packed bed reactor where the plug flow assumption is invalid.