-
Sukeo Onodera, Masakazu Sugimoto, Tsuyoshi Takagi, Kazuo Tanaka
1999 年 45 巻 1 号 p.
1-7
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
Surface sediments were collected from eight sampling points, representing upper, mid-and downstream regions, of the Tama River, to obtain background information on the polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/DF) levels, profiles and transport in this river. The sediment profiles of PCDD/DF were strongly dependent on the sampling points, with total PCDD/DF levels ranging from 27.0 to 231.6pg/g dry weight (mean value, 90.7pg/g) and the I-TEQ values ranging from 0.05 to 2.8pg/g (mean value, 1.2pg/g). Two maxima in the PCDD/DF concentrations were observed for the sediment samples taken from stations 3 (midstream) and 7 (upstream) in this river, although none for the samples from downstream (industrial area). Sediment samples taken from the midstream near waste water discharges and a municipal solid waste (MSW) incinerator plant showed high TEQ values of 0.5 to 1.2 and 13.0pg/g, respectively, indicating a potential PCDD/DF source in this river. In contrast, the PCDD/DF concentrations in the sediment samples taken from five tributaries flowing into the midstream region were very low, indicating no PCDD/DF impact into the studied areas. These data suggest a multiplicity of sources ranging from agricultural activities to urban activities such as emission gas from MSW incinerators and effluents from wastewater treatment plants.
抄録全体を表示
-
Takayuki Nakahama, Shigenori Sarutani, Yoshio Inouye
1999 年 45 巻 1 号 p.
8-14
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
Trichloroethylene (TCE) is a highly toxic compound which belongs to the class of volatile halogenated hydrocarbons, which are well-known pollutants of drinking water and the atmosphere. The effects of moderately toxic concentration of TCE on the levels of cytochrome P450 (CYP) isoforms and on their phenobarbital (PB) induction in rats were studied. Monooxygenase activities associated with individual CYP isoforms, i.e., CYP1A, 2B, 2E1 and 3A, were measured in microsomal fractions prepared from both lungs and livers of male and female Wistar rats (7-weeks old). Differences in constitutive levels of CYP isoforms were observed between liver and lung of mock-treated rat ; microsomal CYP2B activity was solely detected in lung while the activities of CYP1A, 2EI and 3A, but not 2B were detected in liver. Among these, the pulmonary CYP2B and hepatic CYP2E1 activities were reduced by TCE-treatment. PB-treatment resulted in the detection of increased levels of hepatic CYP1A and 2E1 and of pulmonary CYP2B activities, and also the appearance of hepatic CYP2B activity. Coadministration of TCE was suppressive against the activities of CYP isoforms except for hepatic CYP2E1 in PB-treated rats. The lowered CYP2B activity in the presence of TCE was accompanied by the reduction in the amount of CYP2B apoprotein.
抄録全体を表示
-
Baoxu Zhang, Masahiko Satoh, Chiharu Tohyama
1999 年 45 巻 1 号 p.
15-19
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
To investigate the possible involvement of metallothionein (MT) in acetaminophen (AC)-induced liver damage, MT-I and MT-II gene knock-out transgenic mice (MT-null mice) and wild-type control mice were i.p. treated with AC at a single dose of 250mg/kg and compared. At 24h after AC treatment severe liver damage characterized by necrosis of hepatocytes and increased serum GPT activity was found in MT-null mice while a limited degree of change such as a slight increase in serum GPT activity without necrosis was observed in wild-type mouse liver. MT-null hepatocytes also showed elevated PCNA (proliferating cell nuclear antigen)-positive activity around the necrosis area. AC administration resulted in an increase in lipid peroxidation in MT-null mice, but not in the wild-type mice. The liver in the wild-type mice showed an increased MT amount after AC treatment. These results indicate that MT acts as an endogenous defensive factor against AC-induced hepatotoxicity via oxidative stress.
抄録全体を表示
-
Atsushi Takeda, Yuka Kodama, Shoji Okada
1999 年 45 巻 1 号 p.
20-23
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
Brain parenchyma is protected against excess metals by the barrier system in the brain. To evaluate the expression of metallothionein (MT), a protective protein against heavy metals, in the brain parenchyma, zinc sulfate (0.2 or 2μmol) or cadmium chloride (2 or 20nmol) was injected into the left striatum of rats. Seventy-two h later, the MT level in the ipsilateral striatum injected with 0.2μmol of zinc sulfate was not significantly higher than that after injection with vehicle. When the striatum was injected with 2μmol of zinc sulfate, on the other hand, the MT level in the ipsilateral striatum, showing apparent degeneration, was significantly higher than that after injection with vehicle : the former was approximately 1.5 times the latter. In the case of injection with cadmium chloride at doses of 2 and 20nmol, the MT levels in the ipsilateral striatum was approximately twice that after injection with vehicle. The MT level in the contralateral striatum and other brain regions were not affected by injection with either metal salt at any dose. When zinc sulfate of 100μmol/kg body weight, corresponding to the lower dose tested(0.1μmol/g brain), was subcutaneously injected, the hepatic MT level was approximately four times higher than the normal hepatic level. These results suggest that the changes of MT level in the brain were small compared to those observed in the liver.
抄録全体を表示
-
Kimiko Hirayama, Akira Yasutake
1999 年 45 巻 1 号 p.
24-27
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
To elucidate the involvement of reactive oxygen in in vivo demethylation of methylmercury(MeHg), the effects of paraquat (PQ) and other reactive oxygen modulators on inorganic-Hg (I-Hg) production in MeHg-administered rats were examined. Rats were intravenously (i.v.) injected with MeHgCl (2mg/kg). After MeHg administration, I-Hg levels time-dependently increased in the liver up to 9h, whereas the renal levels did not change during the first 3h, and then increased up to 24h in a time-dependent manner. PQ stimulated I-Hg production in the liver but not in the kidney, whereas it increased 2-thiobarbituric acid-reactive substance (TBA-RS) levels in both tissues. PQ-induced stimulation of I-Hg production was not further accelerated by an OH· enhancer, such as FeSO
4 or Fe(III)EDTA. Hepatic I-Hg production in MeHg-administered rats (without PQ) was suppressed by NaCN (a potent inhibitor of mitochondrial cytochorome oxidase) but not by desferal or Fe(III) EDTA (an OH· modulalator). These results suggest that hepatic mitochondria may play an important role in in vivo demethylation of MeHg, and that reactive oxygen species other than OH· may participate in it.
抄録全体を表示
-
河井 一明
1999 年 45 巻 1 号 p.
28-36
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
Since early 1980s Drosophila melanogaster larvae heterozygous for recessive visible markers and those with defective DNA repair capability have been intensively used as simple in vivo testers of mutagenicity of environmental agents. In pallalel with this activity, the somatic tests have recently been deployed as tools for the detection of modifiers of the mutagenicity and understanding of basic mechanisms of the effects. Here, I characterize the somatic systems in relation to the biotransforming ability of promutagens and the outcomes from the mutagenicity tests and review some aspects of the deployment.
抄録全体を表示
-
宮崎 英男, 鈴木 誠治, 辻坊 裕, 今田 勝美
1999 年 45 巻 1 号 p.
37-41
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
A Ferric-EDTA(Fe-EDTA)-degrading bacterium, strain A-1 was characterized by its physiological properties. The rate of degradation of Fe-EDTA was measured by the titration method and ion chromatography. The former method has the advantage of allowing a greater number of sample measurements of samples at one time. The rate of degradation of Fe-EDTA was higher in a stationary culture than in a shaked one. The optimum pH for the degradation rate was approximately 8.2. Strain A-1 grew in the presence of various kinds of metal-EDTA chelates, but a Na salt, Mg and Ca chelates of EDTA inhibited the growth. Their MICs (minimual inhibitory concentration) were 0.0045, 0.03 and 0.006%, respectively. These characteristics of strain A-1 have similarities to those of strain B-3, but were different from those of Agrobacterium sp. which were reported by Lauff previously (Appl. Environ. Microbiol., 56, 3346 (1990)). All of the detail taxonomic characters indicate that the isolate strain A-1 belongs to a Pseudomonas sp.
抄録全体を表示
-
Makoto Nakai, Yukiko Tabira, Yoshikuni Yakabe, Etsuko Tsukamoto, Yasuy ...
1999 年 45 巻 1 号 p.
P1-1
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Shinobu Kinoshita, Mitsuhiro Wada, Naotaka Kuroda, Kenichiro Nakashima
1999 年 45 巻 1 号 p.
P2-2
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Atsuko Takeuchi, Toshio Okano
1999 年 45 巻 1 号 p.
P3-3
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Tomoo Shibahara, Yoshihisa Kato, Koichi Haraguchi, Shinya Yumoto, Yosh ...
1999 年 45 巻 1 号 p.
P4-4
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kazumi Sugihara, Kazuhiro Shimomiya, Shigeyuki Kitamura, Shigeru Ohta, ...
1999 年 45 巻 1 号 p.
P5-5
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Shigeki Shimba, Hideko Sone, Junzo Yonemoto, Masakatsu Tezuka
1999 年 45 巻 1 号 p.
P6-6
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Akira Hiratsuka, Hiroshi Saito, Kenichiro Hirose, Tadashi Watabe
1999 年 45 巻 1 号 p.
P7-7
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yuji Okamoto, Shigeyuki Kitamura, Mitsuhiro Takeshita, Shigeru Ohta
1999 年 45 巻 1 号 p.
P8-8
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Takafumi Ochi
1999 年 45 巻 1 号 p.
P9-9
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yoshiyuki Nakamura, Ayako Hirasawa, Takeshi Honma, Masakuni Degawa
1999 年 45 巻 1 号 p.
P10-10
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Satoshi Watanabe, Akiko Ishiguro, Shin-ichi Togashi, Masami Ohishi, No ...
1999 年 45 巻 1 号 p.
P11-11
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Hiroyasu Yamazaki, Yoko Orito, Sachiko Katayama, Aki Kamei, Takako Yam ...
1999 年 45 巻 1 号 p.
P12-12
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yasuyuki Fujiwara, Toshiyuki Kaji
1999 年 45 巻 1 号 p.
P13-13
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Sachiyo Takefuta, Atsushi Takeda, Hiromi Ijiro, Miho Ohnuma, Jinko Saw ...
1999 年 45 巻 1 号 p.
P14-14
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yumiko Nakamura, Yukari Tsumura, Yasuhide Tonogai, Tadashi Shibata
1999 年 45 巻 1 号 p.
P15-15
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Hideaki Kido, Mitsuhiro Wada, Naotaka Kuroda, Masaharu Shironita, Keni ...
1999 年 45 巻 1 号 p.
P16-16
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Sadahiro Kawazoe, Yuki Tanimoto, Fumie Kurita, Tamio Mizutani
1999 年 45 巻 1 号 p.
P17-17
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Hideto Jinno, Tamao Ozawa, Nobumitsu Hanioka, Toshiko Tanaka-Kagawa, T ...
1999 年 45 巻 1 号 p.
P18-18
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Takumi Ishida, Daisuke Maji, Yuko Yoshioka, Yuji Ishii, Kazuta Oguri
1999 年 45 巻 1 号 p.
P19-19
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kazuo Asaoka, Tetuo Satoh, Akira Narita
1999 年 45 巻 1 号 p.
P20-20
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yoshihisa Kato, Koichi Haraguchi, Shinya Yumoto, Tomoo Shibahara, Hiro ...
1999 年 45 巻 1 号 p.
P21-21
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Tomoyuki Odani, Tsuyoshi Nakanishi, Akiko Matuyama, Norio Itoh, Keiich ...
1999 年 45 巻 1 号 p.
P22-22
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Tomoki Kimura, Isami Fujita, Tsuyoshi Nakanishi, Norio Itoh, Norio Mut ...
1999 年 45 巻 1 号 p.
P23-23
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Atsuko Adachi, Sokichi Takagi, Tomoko Komiyama, Tomoko Tanaka, Maki Na ...
1999 年 45 巻 1 号 p.
P24-24
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Hitoshi Ueno, Koji Oishi, Tomoyuki Kubota, Yasuyoshi Sayato, Katsuhiko ...
1999 年 45 巻 1 号 p.
P25-25
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kazuhito Watanabe, Naomi Akagi, Masato Usuki, Maki Yamada, Noriyuki Us ...
1999 年 45 巻 1 号 p.
P26-26
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Toshiko Tanaka-Kagawa, Hideto Jinno, Nobumitsu Hanioka, Tetsuji Nishim ...
1999 年 45 巻 1 号 p.
P27-27
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kenzo Yamanaka, Akira Hasegawa, Hirotaka Sonoki, Mikio Hoshino, Shoji ...
1999 年 45 巻 1 号 p.
P28-28
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kazuo Asaoka, Yasushi Sakamoto, Kazuyuki Yano
1999 年 45 巻 1 号 p.
P29-29
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Mariko Tachikawa, Takasi Aburada, Masakatsu Tezuka, Ryoji Sawamura
1999 年 45 巻 1 号 p.
P30-30
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Sawako Miyajima, Chika Yamamoto, Yasuyuki Fujiwara, Toshiyuki Kaji, Fu ...
1999 年 45 巻 1 号 p.
P31-31
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Naomi Kudo, Erika Suzuki, Kohtaro Ohmori, Yoichi Kawashima
1999 年 45 巻 1 号 p.
P32-32
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Tetsuya Murakami, Masaki Watanabe, Masakatsu Tezuka
1999 年 45 巻 1 号 p.
P33-33
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yasuji Hojo, Yasuko Asano, Yuko Tonan
1999 年 45 巻 1 号 p.
P34-34
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yasuhiro Ishibashi, Yasuhiro Tabira, Yoshinobu Joh, Yuji Takao, Shinya ...
1999 年 45 巻 1 号 p.
P35-35
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Ayako Fukuda, Ryuichi Kurogi, Kenji Tasaki, Takumi Ishida, Yuji Ishii, ...
1999 年 45 巻 1 号 p.
P36-36
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Shinya Kohra, Nobuaki Tominaga, Yoshinori Mitsui, Yuji Takao, Yasuhiro ...
1999 年 45 巻 1 号 p.
P37-37
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Fumi Dakeyama, Jun-ichi Nishikawa, Jun Goto, Koichi Saito, Masayoshi I ...
1999 年 45 巻 1 号 p.
P38-38
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Yuji Takao, Ho Chul Lee, Yasuhiro Ishibashi, Shinya Kohra, Nobuaki Tom ...
1999 年 45 巻 1 号 p.
P39-39
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Katsuhiko Saido, D.L. Daubaras, Olga Zaborina, A.M. Chakrabarty
1999 年 45 巻 1 号 p.
P40-40
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Kiyomatsu Hashizume, Chitose Toda, Teruyo Yasui, Hideo Nagano, Tsutomu ...
1999 年 45 巻 1 号 p.
P41-41
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー
-
Sokichi Takagi, Atsuko Adachi, Chiho Ikeda, Norie Fukao, Emi Yoshii, T ...
1999 年 45 巻 1 号 p.
P42-42
発行日: 1999/02/28
公開日: 2008/04/14
ジャーナル
フリー