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971.
Toshimasa Shiraishi Hiroshi Sakai Kentaro Ikeda Toshihiko Urushibara 《Journal of General Plant Pathology》2014,80(6):475-478
Various methods of inoculating plants with Verticillium dahliae have been described; however, so far, there are no effective preparations of its microsclerotia, a major source of infection under natural field conditions. In this study, we developed a simple and effective method to prepare microsclerotial inoculum of V. dahliae using a cellophane medium that effectively promoted microsclerotia formation. In addition, a sieving process allowed the preparation of inoculum exclusively composed of microsclerotia. Our novel method provides a reproducible and stable inoculum for disease induction by V. dahliae under conditions that approximate natural infections. 相似文献
972.
Hiroshi Hayakawa Maiko Akasaka Yoshiko Shimono Shunji Kurokawa Tomoko Nishida Hiroaki Ikeda Toru Wakamatsu 《Weed Biology and Management》2014,14(4):251-261
Nucleotide sequence variations were investigated with respect to the geographical distribution patterns of Miscanthus sinensis populations that were sampled from 26 Japanese national parks and three populations of the Ryukyu Islands. Twelve homozygous sequences in the nuclear ribosomal DNA internal transcribed spacer region were detected. The populations of M. sinensis in mainland Japan mainly were composed of a monophyletic group with a symapomorphic character, whereas those in the Ryukyu Islands included a polyphyletic group. Only an internal transcribed spacer haplotype with a plesiomorphic character was found in both mainland Japan and the Ryukyu Islands. Thus, no clear geographical isolation was observed in this species. These facts might be caused by the ability of M. sinensis as a pioneer plant to have a high migration potential and high gene flow by outcrossing. On the basis of the results of this study (nuclear ribosomal DNA) and the previous study (chloroplast DNA), a phylogeographical history of M. sinensis was presumed where the ancestral and derived lineages were distributed in the southern and northern regions of Japan, respectively, without strict geographical isolation. 相似文献
973.
974.
975.
Sumito MATSUYA Hiroyuki IMAI Yasuo KISO Ken Takeshi KUSAKABE Kiyoshi KANO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1244
We determined the nucleotide sequence of the growth hormone (Gh) gene in Mus minutoides, one of the smallest mammals, where was predicted to be distinct in the functional regions between M. minutoides and Mus musculus. To investigate the evolutionary characteristics of Gh in M. minutoides, we constructed a phylogenetic tree based on the putative amino acid sequences of Gh, suggesting that the Gh of M. minutoides diverged earlier than M. musculus. Furthermore, the Gh gene expressed higher in M. minutoides than in M. musculus. Our results suggest that the specific feature of the Gh in M. minutoides is in rather the regulatory mechanism than the sequence. 相似文献
976.
Viral movement in the leaf tissues of a resistant host, Cucumis figarei, inoculated with the pepo strain of Cucumber mosaic virus (CMV) and incubated at 24°C or 36°C was investigated by fluorescence in situ hybridization (FISH), leaf-press blotting, tissue printing and immunogold-silver staining techniques. Observation by FISH
revealed that at 24°C most infection sites with CMV at 0.01 mg/ml or 0.1 mg/ml were limited to a single cell during the incubation
period, that the number of infection sites increased from 24hpi (hours post inoculation) to 80 hpi in the leaves inoculated
with CMV at 0.5 mg/ml, and that the size as well as the number of infection sites rapidly increased with time in the leaves
inoculated with CMV at 2.0 mg/ml. These results suggested that one factor for the resistance of C. figarei at 24°C might be an inhibition of viral movement in and out of the infection sites. Leaf-press blotting and tissue blotting
indicated that CMV remained in the infection sites at 24°C, whereas it spread from the inoculated leaves to other parts of
the plants through vascular systems at 36°C. Immunogold-silver staining demonstrated that at 24°C CMV infected bundle sheath
(BS) cells in minor veins, whereas at 36°C it invaded not only BS cells, but also phloem parenchyma (PP)/ companion cell (CC)
or PP/intermediary cell (IC) complexes in minor veins in the regions with chlorotic symptoms. These results indicated that
at 24°C CMV had difficulty in passing through the interface between BS and PP/CC or PP/ IC complexes and that viral entry
from mesophyll to the phloem pathway was inhibited in the inoculated leaves.
Received 26 August 1999/ Accepted in revised form 14 December 1999 相似文献
977.
978.
Kazushi Kusakabe Masaki Hata Jun Shoji Masakazu Hori Takeshi Tomiyama 《Fisheries Science》2017,83(2):215-219
To determine the optimal temperature for juvenile (0 year old) marbled flounder Pseudopleuronectes yokohamae, juveniles of 40–54 mm standard length were reared at six temperature conditions in the range of 8–26 °C, using group- and individual-based methods. Growth of juveniles increased from 8 to 20 °C but decreased from 20 to 26 °C, irrespective of the rearing method used. Food intake was greatest at 20 and 24 °C compared with other temperatures, while feed conversion efficiency was greater at 20 °C than 24 °C in individual rearing. Individual rearing provided more information such as individual variations in growth and food consumption, suggesting the importance of individual-based experiments for exploring the optimal temperature for fish. 相似文献
979.
Takeshi Hano Katsutoshi Ito Kumiko Kono Mana Ito Nobuyuki Ohkubo Kazuhiko Mochida 《Fish physiology and biochemistry》2017,43(1):137-152
This study was performed to unravel the mechanism of the beneficial action of taurine on marine teleost fish, red sea bream (Pagrus major), by analyzing the hepatic metabolism. Moreover, the ameliorative effects of the nutrient against cadmium toxicity and bioaccumulation were further evaluated. The fish were fed a diet containing 0 % (TAU0 %), 0.5 % (TAU0.5 %), or 5.0 % (TAU5.0 %) taurine for 40–55 days (d) and subjected to cadmium acute toxicity and bioaccumulation tests. Taurine deficiency in feed severely affected growth and the hepatic metabolic profiles of the fish, including a remarkable increase in myo-inositol, aspartate, and ß-alanine in the TAU0 % group, which indicates a complementary physiological response to taurine deficiency. For the acute toxicity test, fish were fed the test diets for 55 d and were then exposed to different dose of cadmium ranging from 0 to 5.6 mg/L for 96 h. Fish fed taurine had a higher tolerance to cadmium than those not fed taurine. For the bioaccumulation test, fish were fed the test diets for 40 d and then were chronically exposed to 0.2 mg/L of cadmium for 28 d followed by depuration for 21 d. Cadmium concentrations in the liver and muscle of fish fed TAU5.0 % were significantly lower than those of fish fed TAU0 % for the first 7 d of exposure and the first 7 d of elimination. Our findings suggest a possible mechanism for the beneficial role played by taurine and that the inclusion of taurine in fish aquaculture feed may reduce cadmium contamination of fish intended for human consumption. 相似文献
980.
Shigeru Hisada Kenjiro Tsubota Kenji Inoue Hisaharu Yamada Takanori Ikeda Frank D. Sistare 《Journal of toxicologic pathology》2022,35(1):53
The pharmacokinetic endpoint of a 25-fold increase in human exposure is one of the specified criteria for high-dose selection for 2-year carcinogenicity studies in rodents according to ICH S1C(R2). However, this criterion is not universally accepted for 6-month carcinogenicity tests in rasH2-Tg mice. To evaluate an appropriate multiple for rasH2-Tg mice, we evaluated data for 53 compounds across five categories of rasH2-Tg mouse-positive [(1) genotoxic and (2) non-genotoxic] carcinogens and rasH2-Tg mouse-negative [(3) non-genotoxic carcinogens with clear or uncertain human relevance; (4) non-genotoxic rodent-specific carcinogens; and (5) non-carcinogens], and surveyed their tumorigenic activities and high doses in rasH2-Tg mice and 2-year rodent models. Our survey indicated that area under the curve (AUC) margins (AMs) or body surface area-adjusted dose ratios (DRs) of tumorigenesis in rasH2-Tg mice to the maximum recommended human dose (MRHD) were 0.05- to 5.2-fold in 6 category (1) compounds with small differences between models and 0.2- to 47-fold in 7 category (2) including three 2-year rat study-negative compounds. Among all 53 compounds, including 40 compounds of the rasH2-Tg mouse-negative category (3), (4), and (5), no histopathologic risk factors for rodent neoplasia were induced only at doses above 50-fold AM or DR in rasH2-Tg mice except for two compounds, which induced hyperplasia and had no relationship with the tumors observed in the rasH2-Tg mouse or 2-year rodent studies. From the results of these surveys, we confirmed that exceeding a high dose level of 50-fold AM in rasH2-Tg mouse carcinogenicity studies does not appear to be of value. 相似文献