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71.
Ryota Takeuchi Mitsuru Jimbo Fumika Tanimoto Mariko Iijima Hiroshi Yamashita Go Suzuki Saki Harii Yoshikatsu Nakano Ko Yasumoto Shugo Watabe 《Marine drugs》2021,19(3)
Many corals establish symbiosis with Symbiodiniaceae cells from surrounding environments, but very few Symbiodiniaceae cells exist in the water column. Given that the N-acetyl-d-glucosamine-binding lectin ActL attracts Symbiodiniaceae cells, we hypothesized that corals must attract Symbiodiniaceae cells using ActL to acquire them. Anti-ActL antibody inhibited acquisition of Symbiodiniaceae cells, and rearing seawater for juvenile Acropora tenuis contained ActL, suggesting that juvenile A. tenuis discharge ActL to attract these cells. Among eight Symbiodiniaceae cultured strains, ActL attracted NBRC102920 (Symbiodinium tridacnidorum) most strongly followed by CS-161 (Symbiodinium tridacnidorum), CCMP2556 (Durusdinium trenchii), and CCMP1633 (Breviolum sp.); however, it did not attract GTP-A6-Sy (Symbiodinium natans), CCMP421 (Effrenium voratum), FKM0207 (Fugacium sp.), and CS-156 (Fugacium sp.). Juvenile polyps of A. tenuis acquired limited Symbiodiniaceae cell strains, and the number of acquired Symbiodiniaceae cells in a polyp also differed from each other. The number of Symbiodiniaceae cells acquired by juvenile polyps of A. tenuis was correlated with the ActL chemotactic activity. Thus, ActL could be used to attract select Symbiodiniaceae cells and help Symbiodiniaceae cell acquisition in juvenile polyps of A. tenuis, facilitating establishment of symbiosis between A. tenuis and Symbiodiniaceae cells. 相似文献
72.
Tadeusz Magiera Beata Gołuchowska Mariola Jabłońska 《Water, air, and soil pollution》2013,224(1):1-17
During this study, we investigated the mineralogical characterization of technogenic magnetic particles (TMPs) contained in alkaline industrial dust and fly ash emitted by coal burning power plants and cement plants. The reaction of tested dust samples varied between values of pH 8 and pH 12. Their magnetic properties were characterized by measurement of magnetic susceptibility (χ), frequency dependence of magnetic susceptibility (χfd), and temperature dependence of magnetic susceptibility. Mineralogical and geochemical analyses included scanning electron microscopy with energy dispersive spectroscopy, microprobe analysis and X-ray diffraction. The TMPs in fly ash from hard coal combustion have the form of typical magnetic spherules with a smooth or corrugated surface as well as a skeletal morphology, composed of iron oxides (magnetite, maghemite, and magnesioferrite) that occurred in the form of incrustation on the surface of mullite, amorphous silica, or aluminosilicate particles. The TMPs observed in fly ash from lignite combustion have a similar morphological form but a different mineralogical composition. Instead of magnetite and magnesioferrite, maghemite and hematite with lower χ values were the prevailing magnetic minerals, which explains the much lower magnetic susceptibility of this kind of ash in comparison with the ash from hard coal combustion, and probably results from the lower temperature of lignite combustion. Morphology and mineralogical composition of TMPs in cement dust is more diverse. The magnetic fraction of cement dust occurs mostly in the form of angular and octahedral grains of a significantly finer granulation (<20 μm); however, spherules are also present. A very characteristic magnetic form for cement dust is calcium ferrite (CaFe3O5). The greatest impact on the magnetic susceptibility of cement dust results from iron-bearing additives (often waste materials from other branches of industry), which should be considered the most dangerous to the environment. Stoichiometric analysis of micro-particles confirmed the presence of heavy metals such as Pb, Mn, Cd, and Zn connected with TMPs, which are carriers of magnetic signals in atmospheric dust. Therefore, in some cases, their presence in topsoil when detected by magnetic measurement can be treated as an indicator of inorganic soil contamination. 相似文献
73.
Kaji Ryoma Yariuchi Rina Fujii Yumi Taniguchi Shiduku Uji Yuya Suzuki Go Kashihara Keita Kisaki Gan Suezawa Katsuhiko Ohtani Mamoru Kataoka Ikuo Akimitsu Kazuya Gomi Kenji 《Journal of General Plant Pathology》2021,87(6):361-365
Journal of General Plant Pathology - Kiwifruit bacterial canker, which is caused by Pseudomonas syringae pv. actinidiae biovar 3 (Psa3), is found throughout kiwifruit-growing countries. Here, we... 相似文献
74.
Mami OIKAWA Shogo MATOBA Kimiko INOUE Satoshi KAMIMURA Michiko HIROSE Narumi OGONUKI Hirosuke SHIURA Michihiko SUGIMOTO Kuniya ABE Fumitoshi ISHINO Atsuo OGURA 《The Journal of reproduction and development》2013,59(3):231-237
In mice, one of the major epigenetic errors associated with somatic cell nuclear
transfer (SCNT) is ectopic expression of Xist during the preimplantation
period in both sexes. We found that this aberrant Xist expression could
be impeded by deletion of Xist from the putative active X chromosome in
donor cells. In male clones, it was also found that prior injection of
Xist-specific siRNA could significantly improve the postimplantation
development of cloned embryos as a result of a significant repression of
Xist at the morula stage. In this study, we examined whether the same
knockdown strategy could work as well in female SCNT-derived embryos. Embryos were
reconstructed with cumulus cell nuclei and injected with Xist-specific
siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment
successfully repressed Xist RNA at the morula stage, as shown by the
significant decrease in the number of cloud-type Xist signals in the
blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”)
and numbers of Xist RNA signals remained within single embryos. After
implantation, the dysregulated Xist expression was normalized
autonomously, as in male clones, to a state of monoallelic expression in both embryonic
and extraembryonic tissues. However, at term there was no significant improvement in the
survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective
in repressing the Xist overexpression in female cloned embryos but failed
to rescue them, probably because of an inability to mimic consistent monoallelic
Xist expression in these embryos. This could only be achieved in female
embryos by applying a gene knockout strategy rather than an siRNA approach. 相似文献
75.
Minami W. OKUYAMA Michito SHIMOZURU Go ABE Mariko NAKAI Mariko SASHIKA Ken-Ichiro SHIMADA Nobuhiro TAKAHASHI Daisuke FUKUI Ryohei NAKAMURA Toshio TSUBOTA 《The Journal of reproduction and development》2013,59(4):361-367
The raccoon (Procyon lotor), indigenous to North America, has
naturalized in Japan as an invasive alien species, having been introduced into the country
in the 1970s. In Hokkaido, the northernmost island of Japan, feral raccoons have been
increasing in number and spreading throughout the island. The age at the onset of puberty
for raccoons is important for estimating individual lifetime reproductive success and
population growth. The present study investigated the timing of and potential factors
affecting the onset of puberty in male raccoons in Hokkaido. External characteristics and
histology of testes were studied in 151 male feral raccoons and in 1 captive juvenile. For
the majority of feral yearling raccoons, prepubertal development began in May, and
spermatozoa production began in October prior to their second mating season. However, some
larger juveniles attained puberty during the juvenile period. The captive juvenile, which
was fed throughout the winter, attained puberty only 11 months after birth. These results
suggest that if male raccoons can achieve enough body growth before the first mating
season, puberty can be attained early. In both juveniles and yearlings, spermatozoa
production was only observed after autumn. This timing coincided with the recrudescence of
seasonally active spermatogenesis in adult males. Therefore, attaining puberty in male
raccoons appears to require both adequate body nutrient development and several
environmental factors that control seasonal testicular changes. 相似文献
76.
Kensuke Hirose Satoshi Mikawa Naohiko Okumura Go Noguchi Kazuo Fukawa Naoe Kanaya Ayumi Mikawa Aisaku Arakawa Tetsuya Ito Yoichi Hayashi Fumio Tachibana Takashi Awata 《Animal Science Journal》2013,84(3):213-221
Vertnin (VRTN) is involved in the variation of vertebral number in pigs and it is located on Sus scrofa chromosome 7. Vertebral number is related to body size in pigs, and many reports have suggested presence of an association between body length (BL) and meat production traits. Therefore, we analyzed the relationship between the VRTN genotype and the production and body composition traits in purebred Duroc pigs. Intramuscular fat content (IMF) in the Longissimus muscle was significantly associated with the VRTN genotype. The mean IMF of individuals with the wild‐type genotype (Wt/Wt) (5.22%) was greater than that of individuals with the Wt/Q (4.99%) and Q/Q genotypes (4.79%). In addition, a best linear unbiased predictor of multiple traits animal model showed that the Wt allele had a positive effect on the IMF breeding value. No associations were observed between the VRTN genotype and other production traits. The VRTN genotype was related to BL. The Q/Q genotype individuals (100.0 cm) were longer than individuals with the Wt/Q (99.5 cm) and Wt/Wt genotypes (98.9 cm). These results suggest that in addition to the maintenance of an appropriate backfat thickness value, VRTN has the potential to act as a genetic marker of IMF. 相似文献
77.
Kappei Kobayashi Go Atsumi Yasuya Iwadate Reiko Tomita Ken-ichi Chiba Shiho Akasaka Masahiro Nishihara Hideyuki Takahashi Naoto Yamaoka Masamichi Nishiguchi Ken-Taro Sekine 《Journal of General Plant Pathology》2013,79(1):56-63
A virus-like dsRNA of about 23 kbp was detected in gentian plants showing Kobu-sho syndrome including stunting, shortened internodes, and tumors on stems, nodes and roots. Nucleotide sequence analysis has suggested that this dsRNA is related to Pestivirus species but not to any other plant viruses. It was protected from externally added RNase, suggesting that the dsRNA is encapsidated. The dsRNA was co-extracted in a crude homogenate of glutaraldehyde-fixed tissue with the virus-like particles that have been associated previously with Kobu-sho syndrome in gentian (Usugi et al. Jpn J Phytopathol 76:21–24, 2010). The RNA sequence was detected in more than 99 % of Kobu-sho gentian individuals but in less than 20 % of apparently healthy gentian individuals from fields affected with Kobu-sho. Thus, we propose naming the virus Gentian Kobu-sho-associated virus. 相似文献
78.
Go Suzuki Seiji Arakaki Kiyoshi Suzuki Yukihiro Iehisa Takeshi Hayashibara 《Fisheries Science》2012,78(4):801-808
In situ larval seeding is a low-cost technique that is currently under development for the large-scale restoration of coral populations. One problem that still needs to be solved is the preparation of coral larvae for seeding, i.e., how many larvae are required to restore a certain area? In this study, we focused on the relationship between the numbers of larvae, settlers, and survivors for three?months post-settlement to determine the optimal larval seeding density. A comparison of three different larval densities (low, middle, and high) indicated that the number of settlers was proportional to the larval density, suggesting that settler density is determined by the number of larvae supplied. However, the survival rate of settlers on high-density plates was much lower than the corresponding rates on low- or middle-density plates during the first month after settlement. Moreover, most of the seeded corals had not survived on the low-density plates at three?months after settlement. Therefore, the middle larval density (i.e., 5000?larvae?m?2) appears to be optimal for seeding on grid plates. 相似文献
79.
Go Fujita Kumiko Totsu Yoshimi Matsuoka Wataru Kitamura Naoya Masuda 《Biological conservation》2009,142(9):1891-1898
The little tern (Sterna albifrons) is a species of shorebird that nests in colonies on sandy beaches and riverbanks with little vegetation cover. In Japan, the natural breeding habitats of the terns have decreased drastically, and the species is listed under the category “vulnerable” in the Red List of the Government of Japan. To reduce the effects of habitat loss on the terns, conservationists are attempting to create and manage artificial colony sites in highly developed landscapes, such as reclaimed lands located in Tokyo Bay, central Japan. We present the factors that contribute to breeding success for this species and the habitat characteristics related to nest-site selection in the artificial colony sites along Tokyo Bay. Our data show that around 3 ha of a building rooftop without vegetation cover could sustain more than 2000 little tern nests. We found a strong positive relationship between colony size and hatching success, observing that a colony size of more than 100 lowered predation rates of eggs. On sites built upon white crushed-concrete, nest densities were high and predation rates of eggs were low. We also found that feeding rates were affected by foraging habitats, of which the best types were the shoreline of sandy beaches and mud flats. The 40 km dispersal range of the breeding terns, inferred from distribution data, should be considered when establishing a network of the multiple colony sites. 相似文献
80.
Susumu S. ABE Sadahiro YAMAMOTO Toshiyuki WAKATSUKI 《Soil Science and Plant Nutrition》2009,55(4):514-522
Termites play a significant role in soil-forming processes of the tropics. The influence of termites on pedogenesis as affected by the toposequence, however, has rarely been explored. We investigated the soil physicochemical and morphological characteristics of epigeal mounds constructed by Macrotermes bellicosus (Smethman) compared with those of surrounding pedons along a toposequence (bottom, fringe and upland sites) of an inland valley in central Nigeria. The physicochemical and morphological properties of the mound soils varied according to structural units but were generally different from those of the adjacent pedons. The differences included finer texture, higher electrical conductivity, total N, exchangeable bases (Ca, Mg and K) and effective cation exchange capacity and lower C/N ratio and exchange acidity in the mound than the pedon at each toposequence position. This tendency to modify the soil properties was more prominent in the nest body where the termites actually live, that is, in the hives, royal cell and base-plate, than in the soils below the nest and the other mound parts, that is, the external wall, internal wall and pillars. We found this trend to a greater or lesser degree at all toposequence positions. Our findings suggest that: (1) M. bellicosus can manipulate the mound soils according to functional applications of structure units or environmental requirements for its livelihood, regardless of local soils; (2) M. bellicosus makes ecological patches (hot spots) at all toposequence positions in the same measure; (3) the influence of M. bellicosus on the pedogenesis is reduced in the lowlands compared with the uplands because the number and volume of the mounds were substantially lower in the bottom and fringe sites compared with the upland site. 相似文献