Evaluation of the Affinity of Some Toxic Elements to Schwertmannite in Natural Streams Contaminated with Acid Mine Drainage     

Tetsushi Nagano  Nobuyuki Yanase  Yukiko Hanzawa  Morio Takada  Hisayoshi Mitamura  Tsutomu Sato  Hirochika Naganawa 《Water, air, and soil pollution》2011,216(1-4):153-166

In order to evaluate fixation potential of schwertmannite for fluvial transport of various toxic elements, we examined bottom precipitates and stream waters collected from the rivers contaminated with acid mine drainage (AMD), which arose from the abandoned Nishinomaki mine (Shimonita, Gunma, Japan). Mineralogical and morphological observations revealed that schwertmannite was the main mineral of the precipitates. The affinity of various toxic ions to schwertmannite was evaluated on the basis of (1) apparent solid?Cliquid partition coefficients (K _d??s) between precipitates and stream waters, (2) coprecipitation behaviors during schwertmannite formation in a laboratory test, and (3) consideration on coprecipitation processes using partial charge model (PCM). As a result, oxyanions of V, As, Mo and Sb, K _d??s of which were relatively large (>10⁴ (ml g^?1)), were considered to be immobilized by schwertmannite precipitates. A laboratory test also demonstrated that these ions except Mo coprecipitated with schwertmannite. In addition, partial charges and average electronegativities predicted on the basis of PCM suggested that the oxyanions of V, As, Mo, and Sb could create stable inner sphere complexes with schwertmannite embryos, which results in their high affinity to schwertmannite. On the other hand, cationic ions of Mn, Cu, Zn, Sr, Cs, and U, K _d??s of which were relatively small (<10⁴ (ml g^?1)), were thought to have a tendency to flow downstream without uptake by schwertmannite precipitates. All these results suggested that schwertmannite has high fixation potential for fluvial transport of various toxic oxyanions in AMD-contaminated rivers.  相似文献   

Marine sponge: a potential source for methoxylated polybrominated diphenyl ethers in the Asia-Pacific food web     

Haraguchi K  Kato Y  Ohta C  Koga N  Endo T 《Journal of agricultural and food chemistry》2011,59(24):13102-13109

Marine sponges collected in Palau, Micronesia, were investigated for hydroxylated or methoxylated analogues of brominated diphenyl ethers (BDEs), brominated dibenzo-p-dioxin (BDD), and brominated biphenyls. The neutral fractions of Haliclona sp. and Callyspongia sp. contained 2'-methoxy-2,3',4,5'-tetraBDE, 6-methoxy-2,2',4,4'-tetraBDE, 2',6-dimethoxy-2,3',4,5-tetraBDE 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl, several methoxy-triBDEs, and dimethoxy-penta-/hexaBDEs. The methoxylated BDEs in sponges were strikingly similar to those of local fish living in the western Pacific Ocean. The total concentrations of these compounds (ΣMeO-PBDE) in both sponges were 63.5 μg/g extractable organic matter (EOM) for Haliclona sp. and 36.5 μg/g EOM for Callyspongia sp., which were about 2 orders of magnitude higher than the levels seen in tropical coral reef fish (unicornfish or surgeonfish) (280-290 ng/g lipid) and groupers (550 ng/g lipid) from Okinawan coastal waters. The phenolic fractions of both sponges contained hydroxy-methoxy tetra-/pentaBDEs as well as hydroxy-tetraBDD, in addition to the corresponding phenolic tetraBDE analogues. Although the total concentrations of phenolic products (27-80 μg/g EOM) in both sponges fell within a range comparable to the methoxylated products, ΣOH-PBDE in local fish were trace level (less than 10 ng/g lipid of) or undetectable. This survey indicates that marine sponges are a possible source of the MeO-PBDE analogues that biomagnify via the food chain to the higher trophic organisms in the western Pacific, whereas the distribution of the corresponding hydroxylated analogues is limited.  相似文献   

Some characteristics of rapidly labeled nucleic acids in barley coleoptiles grown at cold temperature     

Nobuyuki Shiomi  Shiro Hori 《Soil Science and Plant Nutrition》2013,59(3):93-96

Some plants, for example winter wheat, require a low temperature period during the early germination and establishment stage to further flowering. In another case, the incubation of plant seeds at low temperature promotes their flowering. The phenomenon was named “jarovization” first by LYSENKO and WUYTE later suggested the name “vernalization” (1).  相似文献   

Relationship between nitrogen fixation and numbers of cyanobionts and heterocysts in fifteen Azolla strains     

Kazuhiro Maejima  Eiji Uheda  Nobuyuki Shiomi  Shunji Kitoh 《Soil Science and Plant Nutrition》2013,59(3):447-449

The relationship between nitrogen fixation and the numbers of cyanobionts and heterocysts in the mature leaves of fifteen Azolla strains from five species was examined. The nitrogenase (acetylene reduction) activity per leaf and the numbers of cyanobionts and heterocysts in the mature region varied depending on the Azolla strains. The numbers of cyanobionts and heterocysts, particularly the number of heterocysts, were closely correlated with the nitrogenase activity per leaf. However, the nitrogenase activity per leaf was not correlated with the nitrogenase activity per heterocyst. The results indicate that the variation in the nitrogenase activity of the leaves among Azolla strains mainly resulted from the variation in the number of heterocysts and not from the variation in the nitrogenase activity per heterocyst.  相似文献   

Erratum to: Effect of taurine supplementation on hepatic metabolism and alleviation of cadmium toxicity and bioaccumulation in a marine teleost,red sea bream, <Emphasis Type="Italic">Pagrus major</Emphasis>     

Takeshi Hano  Katsutoshi Ito  Kumiko Kono  Mana Ito  Nobuyuki Ohkubo  Kazuhiko Mochida 《Fish physiology and biochemistry》2017,43(3):911-912

  相似文献   

Early cell enlargement by night-time heating of fruit produce watermelon fruit (Citrullus lanatus Matsum. et Nakai) with high sucrose content     

Youichi Ikeshita  Yuri Kanamori  Nobuyuki Fukuoka  Jun Matsumoto  Yasutaka Kano 《Scientia Horticulturae》2010

To investigate the effects of night-time temperature on cell and fruit size, and sugar accumulation in watermelon fruit, fruits were treated with high night-time temperatures in a greenhouse. The minimum night-time ambient temperature of the heating box (18 °C) was approximately 6 °C higher than that of the control. The length, diameter and weight of heat-treated fruit at the end of heating treatment, 16 days after anthesis (DAA), were significantly greater than that of control fruit, but those at harvesting, 42 DAA, were almost the same in both treatments. Mean cell size of the outer portion of heat-treated fruit at 16 DAA was significantly larger than that of the control. Cell size of the fruits at 42 DAA did not differ between heat-treated and control fruits. Sucrose, glucose and fructose content of fruit at 16 DAA did not differ between heat-treated and control fruit. However, sucrose content of the outer portion of heat-treated fruit was 162% of that of control fruit at 42 DAA. Glucose and fructose contents at 42 DAA did not differ between heat-treated and control fruit, except glucose content of outer portion.  相似文献   

No Mutations of Lysophosphatidic Acid Receptor Genes in Lung Adenocarcinomas Induced by N-Nitrosobis(2-hydroxypropyl)amine in Rats     

Wakabayashi N  Tsujino M  Tajiri M  Taki M  Koshino A  Ikeda H  Fukushima N  Tsujiuchi T 《Journal of toxicologic pathology》2010,23(1):63-66

Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation and migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, frequent mutations of the LPA receptor-1 (LPA1) gene were detected in rat lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine (BHP). In this study, to evaluate the involvement of other LPA receptor gene alterations during lung carcinogenesis, we investigated mutations of the LPA2, LPA3, LPA4 and LPA5 genes in lung adenocarcinomas induced by BHP in rats. Fifteen male Wistar rats, 6 weeks of age, were given 2000 ppm BHP in their drinking water for 12 weeks and then maintained without further treatment until sacrifice at 25 weeks, and 15 adenocarcinomas were obtained. Genomic DNAs were extracted from frozen tissues, and the LPA2, LPA3, LPA4 and LPA5 genes were examined for mutations, using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. No mutations of LPA2, LPA3, LPA4 and LPA5 were detected in the 15 adenocarcinomas. These results suggest that alterations due to LPA2, LPA3, LPA4 and LPA5 gene mutations might not be involved in the development of lung adenocarcinomas induced by BHP in rats.  相似文献   

Feeding events of Japanese lates <Emphasis Type="Italic">Lates japonicus</Emphasis> detected by a high-speed video camera and three-axis micro-acceleration data-logger     

Hideaki Tanoue  Teruhisa Komatsu  Takurou Tsujino  Ippei Suzuki  Masayoshi Watanabe  Hideki Goto  Nobuyuki Miyazaki 《Fisheries Science》2012,78(3):533-538

The feeding events of wild animals have been widely researched in recent decades. The use of invasive methods to determine stomach contents in which the fish is killed can, however, be considered to be unjustifiable in the case of an endangered fish, such as the Japanese late. Here, we report on a method that can be used to verify feeding events of a fish species without the need for killing the fish through the use of a high-speed video camera and a three-axis micro-acceleration data-logger. High-quality images obtained by the video showed that the fish opens its mouth with a quick downward movement of the mandibles and ingests prey via suction feeding. The movement of the mandibles was also simultaneously recorded by changes in the three-axis accelerations obtained by the logger attached to the dorsum. We attached the logger with an automatic release system to the dorsum of one captive Japanese lates and two wild fish together with an acoustic transmitter and then released the fish in the Shimanto River in Japan. After retrieving the logger, the movement records of the fish obtained by the three-axis accelerometer showed the same pattern of feeding events as those in captivity. A total of 13 feeding events at night and five during the daytime were obtained for the three fish during a total 129.7 h of recording.  相似文献   

Isolation of heat-tolerant myoglobin from Asian swamp eel Monopterus albus     

Chotichayapong C  Wiengsamut K  Chanthai S  Sattayasai N  Tamiya T  Kanzawa N  Tsuchiya T 《Fish physiology and biochemistry》2012,38(5):1533-1543

Myoglobin from Asian swamp eel Monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. The purified Mb of 0.68?mg/g wet weight of muscle was determined for its molecular mass by MALDI-TOF-MS to be 15,525.18?Da. Using isoelectric focusing technique, the purified Mb showed two derivatives with pI of 6.40 and 7.12. Six peptide fragments of this protein identified by LC-MS/MS were homologous to Mbs of sea raven Hemitripterus americanus, yellowfin tuna Thunnus albacores, blue marlin Makaira nigicans, common carp Cyprinus carpio, and goldfish Carassius auratus. According to the Mb denaturation, the swamp eel Mb had thermal stability higher than walking catfish Clarias batrachus Mb and striped catfish Pangasius hypophthalmus Mb, between 30 and 60?(°)C. For the thermal stability of Mb, the swamp eel Mb showed a biphasic behavior due to the O(2) dissociation and the heme orientation disorder, with the lowest increase in both Kd(f) and Kd(s). The thermal sensitivity of swamp eel Mb was lower than those of the other Mbs for both of fast and slow reaction stages. These results suggest that the swamp eel Mb globin structure is thermally stable, which is consistent with heat-tolerant behavior of the swamp eel particularly in drought habitat.  相似文献   

Identification of Antiviral Agents Targeting Hepatitis B Virus Promoter from Extracts of Indonesian Marine Organisms by a Novel Cell-Based Screening Assay     

Atsuya Yamashita  Yuusuke Fujimoto  Mayumi Tamaki  Andi Setiawan  Tomohisa Tanaka  Kaori Okuyama-Dobashi  Hirotake Kasai  Koichi Watashi  Takaji Wakita  Masaaki Toyama  Masanori Baba  Nicole J. de Voogd  Shinya Maekawa  Nobuyuki Enomoto  Junichi Tanaka  Kohji Moriishi 《Marine drugs》2015,13(11):6759-6773

The current treatments of chronic hepatitis B (CHB) face a limited choice of vaccine, antibody and antiviral agents. The development of additional antiviral agents is still needed for improvement of CHB therapy. In this study, we established a screening system in order to identify compounds inhibiting the core promoter activity of hepatitis B virus (HBV). We prepared 80 extracts of marine organisms from the coral reefs of Indonesia and screened them by using this system. Eventually, two extracts showed high inhibitory activity (>95%) and low cytotoxicity (66% to 77%). Solvent fractionation, column chromatography and NMR analysis revealed that 3,5-dibromo-2-(2,4-dibromophenoxy)-phenol (compound 1) and 3,4,5-tribromo-2-(2,4-dibromophenoxy)-phenol (compound 2), which are classified as polybrominated diphenyl ethers (PBDEs), were identified as anti-HBV agents in the extracts. Compounds 1 and 2 inhibited HBV core promoter activity as well as HBV production from HepG2.2.15.7 cells in a dose-dependent manner. The EC₅₀ values of compounds 1 and 2 were 0.23 and 0.80 µM, respectively, while selectivity indexes of compound 1 and 2 were 18.2 and 12.8, respectively. These results suggest that our cell-based HBV core promoter assay system is useful to determine anti-HBV compounds, and that two PBDE compounds are expected to be candidates of lead compounds for the development of anti-HBV drugs.  相似文献