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71.
Noriko Suzuki Daisuke Nawa Tseng-Hsiung Su Chia-Wei Lin Kay-Hooi Khoo Kazuo Yamamoto 《PloS one》2013,8(3)
The Galβ1-4Gal epitope is rarely found in mammals, and the natural antibody against Galβ1-4Gal is rich in human. In contrast, we have previously demonstrated the presence of Galβ1-4Gal in pigeon and ostrich, and the absence of this epitope in chicken. Here, to further investigate the expression of this glycan among birds, egg white glycoproteins and egg yolk IgG from nine species of birds, namely, chicken, duck, emu, guineafowl, ostrich, peafowl, pigeon, quail, and turkey, were analyzed by western blot using an anti-(Galβ1-4Gal) antibody. The results indicated that some egg white glycoproteins from emu, ostrich, and quail, and heavy chains of IgG from all of the birds, except chicken and quail, were stained with the antibody. The presence of Galβ1-4Gal on N-glycans of IgGs from guineafowl, peafowl, and turkey were confirmed by mass spectrometry (MS), MS/MS, and MSn analyses. In quail, the presence of Galβ1-4Gal was confirmed by detecting the activities of UDP-galactose: β-galactoside β1,4-galactosyltransferase (β4GalT(Gal)) in various tissues, and by detecting Galβ1-4Gal by western blotting. In contrast, bamboo partridge, which is a close relative of chicken, did not show any detectable activities of β4GalT(Gal) or Galβ1-4Gal on glycoproteins. Because quail, peafowl, turkey, chicken, and bamboo partridge belong to the same family, i.e., Phasianidae, expression of Galβ1-4Gal was most likely differentiated within this family. Considering that Galβ1-4Gal is also expressed in ostrich, emu, and pigeon, which are phylogenetically distant relatives within modern birds, Galβ1-4Gal expression appears to be widely distributed among birds, but might have been abolished in the ancestors of chicken and bamboo partridge. 相似文献
72.
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74.
Yoshinari Moriguchi Kentaro Uchiyama Saneyoshi Ueno Tokuko Ujino-Ihara Asako Matsumoto Junji Iwai Daisuke Miyajima Maki Saito Masaya Sato Yoshihiko Tsumura 《Tree Genetics & Genomes》2016,12(3):57
Cryptomeria japonica pollinosis is one of the most serious allergic diseases in Japan; this is a social problem because C. japonica is the most important Japanese forestry species. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. High-density linkage maps with stable ordering of markers facilitate the localization of male-sterile genes and the construction of partial linkage maps around them in order to develop markers for use in marker-assisted selection. In this study, a high-density linkage map for C. japonica with 2560 markers was constructed. The observed map length was 1266.2 cM and the mean distance between adjacent markers was 0.49 cM. Using information from this high-density map, we newly located two male-sterile genes (ms3 and ms4) on the first and fourth linkage groups, respectively, and constructed partial linkage maps around these loci. We also constructed new partial linkage maps around the ms1 and ms2 loci using additional SNP markers. The closest markers to the ms1, ms2, ms3, and ms4 male-sterile loci were estSNP04188 (1.8 cM), estSNP00695 (7.0 cM), gSNP05415 (3.1 cM), and estSNP01408 (7.0 cM) respectively. These results allowed us to develop SNP markers tightly linked to the male sterile genes for use in MAS; this will accelerate the future isolation of these genes by map-based cloning approaches. 相似文献
75.
Izumi Uno Takashi Kozaka Daisuke Miwa Yoji Kitamura Mohammad Anwar-ul Azim Kazuma Ogawa Junichi Taki Seigo Kinuya Kazuhiro Shiba 《PloS one》2016,11(1)
Purpose
To develop a superior VAChT imaging probe for SPECT, radiolabeled (-)-OIDV and (+)-OIDV were isolated and investigated for differences in their binding affinity and selectivity to VAChT, as well as their in vivo activities.Procedures
Radioiodinated o-iodo-trans-decalinvesamicol ([125I]OIDV) has a high binding affinity for vesicular acetylcholine transporter (VAChT) both in vitro and in vivo. Racemic [125I]OIDV was separated into its two optical isomers (-)-[125I]OIDV and (+)-[125I]OIDV by HPLC. To investigate VAChT binding affinity (Ki) of two OIDV isomers, in vitro binding assays were performed. In vivo biodistribution study of each [125I]OIDV isomer in blood, brain regions and major organs of rats was performed at 2,30 and 60 min post-injection. In vivo blocking study were performed to reveal the binding selectivity of two [125I]OIDV isomers to VAChT in vivo. Ex vivo autoradiography were performed to reveal the regional brain distribution of two [125I]OIDV isomers and (-)-[123I]OIDV for SPECT at 60 min postinjection.Results
VAChT binding affinity (Ki) of (-)-[125I]OIDV and (+)-[125I]OIDV was 22.1 nM and 79.0 nM, respectively. At 2 min post-injection, accumulation of (-)-[125I]OIDV was the same as that of (+)-[125I]OIDV. However, (+)-[125I]OIDV clearance from the brain was faster than (-)-[125I]OIDV. At 30 min post-injection, accumulation of (-)-[125I]OIDV (0.62 ± 0.10%ID/g) was higher than (+)-[125I]OIDV (0.46 ± 0.07%ID/g) in the cortex. Inhibition of OIDV binding showed that (-)-[125I]OIDV was selectively accumulated in regions known to express VAChT in the rat brain, and ex vivo autoradiography further confirmed these results showing similar accumulation of (-)-[125I]OIDV in these regions. Furthermore, (-)-[123I]OIDV for SPECT showed the same regional brain distribution as (-)-[125I]OIDV.Conclusion
These results suggest that radioiodinated (-)-OIDV may be a potentially useful tool for studying presynaptic cholinergic neurons in the brain. 相似文献76.
The macroinvertebrate assemblages in an artificial habitat, the settling basin of a hydroelectric power plant, were investigated and compared with those in a natural habitat, riffles in a nearby river. This study showed that macroinvertebrate density was much higher in the settling basin than in the riffles. Macroinvertebrate assemblage composition differed between the settling basin and the riffles. The difference was probably due to the widespread bryophyte beds in the settling basin. Cincticostella, Brachycentrus, Ephmerella, and chironomid midges, which are usually abundant in bryophyte beds, were present at much higher densities in the settling basin. Cheumatopsyche and Taeniopterygidae were also present at higher densities in the settling basin than in the natural riffles. In contrast, Epeorus was present at lower density in the settling basin than in the natural riffles. This study suggests that the settling basin increases β-diversity in riverine ecosystems. 相似文献
77.
Junichiro Kishi Shinsuke Inuki Natsumi Hirata Emi Kashiwabara Daisuke Yoshidome Osamu Ichihara Yukari Fujimoto 《Bioorganic & medicinal chemistry letters》2019,29(8):970-973
Abstract
CD1d is a non-polymorphic antigen-presenting glycoprotein that recognizes glycolipids as ligands. Ligands bind to the hydrophobic grooves of CD1d, and the resulting ligand-CD1d complexes activate natural killer T (NKT) cells by means of T cell receptor recognition, leading to the secretion of various cytokines. However, details of the ligand recognition mechanism of a large hydrophobic ligand binding pocket and the relationship between cytokine induction and ligand structure are unclear. We report the synthesis of α-GalCer derivatives containing a Bz amide group having various substituting groups in the ceramide moiety, and the analysis of the structure-activity relationships. The assays reveal that the Bz amide-containing CD1d ligands function as NKT cell modulators displaying Th2 cytokine biasing responses. Furthermore, molecular dynamics simulation studies suggest that the phenyl groups can interact with the aromatic amino acid residues in the lipid binding pocket of CD1d. 相似文献78.
Toshihiro Hamajima Fumie Takahashi Koji Kato Yukihito Sugano Susumu Yamaki Daisuke Suzuki Ayako Moritomo Satoshi Kubo Koji Nakamura Kaoru Yamagami Koji Yokoo Hidehiko Fukahori 《Bioorganic & medicinal chemistry》2019,27(6):1056-1064
Chemical optimization of the 5,6,7,8-tetrahydropyrido[4,3-d]pyrimidine (THPP) scaffold was conducted with a focus on cellular potency while maintaining high selectivity against PI3K isoforms. Compound 11f was identified as a potent, highly selective and orally available PI3Kδ inhibitor. In addition, 11f exhibited efficacy in an in vivo antibody production model. The desirable drug-like properties and in vivo efficacy of 11f suggest its potential as a drug candidate for the treatment of autoimmune diseases and leukocyte malignancies. 相似文献
79.
With more than 40,000 species, Malacostraca is the most diverse crustacean class. Most malacostracans are gonochoristic, but simultaneous hermaphrodites are also known. Tanaidacea is one of two malacostracan orders that includes simultaneously hermaphroditic species; so far, simultaneous hermaphroditism has been confirmed externally and internally in only two tanaidacean species, both in the genus Apseudes (Apseudidae). Here we show, through external and internal morphological observations of fixed specimens, that the apseudid Falsapseudes bowmani is a simultaneous hermaphrodite, making Falsapseudes the second tanaidacean genus in which simultaneous hermaphroditism has been confirmed both externally and internally. In this species, the epistome (a projection on the clypeus) was thick and elongate in large specimens but was thin and spiniform in smaller specimens; the brooding of eggs or embryos was observed only in thin‐epistome individuals, although a pair of ovaries was confirmed in both thick‐ and thin‐epistome individuals. This suggests that individuals with a thick epistome may act as males while also retaining the female reproductive organs. 相似文献
80.
Takashi Yazawa Yoshitaka Imamichi Koh‐ichi Yuhki Junsuke Uwada Daisuke Mikami Masayuki Shimada Kaoru Miyamoto Takeshi Kitano Satoru Takahashi Toshio Sekiguchi Nobuo Suzuki Md. Rafiqul Islam Khan Fumitaka Ushikubi Akihiro Umezawa Takanobu Taniguchi 《Molecular reproduction and development》2019,86(7):786-797