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951.
Summary The area postrema of the rabbit, which was perfused with glutaraldehyde and postfixed in osmium tetroxide, was observed under the electron microscope. This area showed neuronal and neuroglial structures similar to those of ordinary cerebral tissue, except for rich blood capillaries, which were surrounded by conspicuous perivascular spaces. Parenchymal cells included a moderate number of small neurons and large numbers of specific astrocyte-like cells. The neuropil consisted of a small number of thin myelinated and many non-myelinated nerve fibers of varying calibers, axo-dendritic synapses, and neuroglial cell processes, leaving no spaces between them. The axons and synaptic terminals contained moderate amounts of granular vesicles, which were similar in size to those found in the hypothalamus and were supposed to contain catecholamine. Glycogen paticles were demonstrated mainly in the cytoplasm of the astrocyte-like cells. 相似文献
952.
Benzyl isothiocyanate attenuates the hydrogen peroxide‐induced interleukin‐13 expression through glutathione S‐transferase P induction in T lymphocytic leukemia cells
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Yue Tang Sho Naito Naomi Abe‐Kanoh Seiji Ogawa Shu Yamaguchi Beiwei Zhu Yoshiyuki Murata Yoshimasa Nakamura 《Journal of biochemical and molecular toxicology》2018,32(6)
We investigated the effect of benzyl isothiocyanate (BITC) on the hydrogen peroxide‐induced gene expression of a T‐helper‐2 cytokine, interleukin (IL)‐13, in T lymphocytic leukemia Jurkat cells. The 24‐h pretreatment of BITC significantly inhibited the IL‐13 expression enhanced by hydrogen peroxide. Although the BITC pretreatment did not change the enhanced level of the phosphorylated c‐Jun N‐terminal kinase (JNK), it significantly inhibited the nuclear translocation of c‐Jun induced by hydrogen peroxide. BITC also increased the protein expression of glutathione S‐transferase (GST) isozymes, GSTP1/2, as well as the total GST activity. A GSTP1/2‐specific inhibitor, 6‐(7‐nitro‐2,1,3‐benzoxadiazol‐4‐ylthio)hexanol (NBDHEX), significantly counteracted the inhibitory effect of BITC on the hydrogen peroxide‐enhanced IL‐13 upregulation as well as the c‐Jun nuclear translocation. Taken together, these results suggested that BITC inhibits the oxidative stress‐mediated IL‐13 mRNA expression, possibly through interference of the c‐Jun phosphorylation by GSTP. 相似文献
953.
Dissociation of Oct-1 from the Nuclear Peripheral Structure
Induces the Cellular Aging-associated Collagenase Gene Expression 总被引:4,自引:0,他引:4
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954.
955.
956.
Plant regeneration from protoplasts of Japanese lawngrass 总被引:12,自引:0,他引:12
Chie Inokuma Kiyoyuki Sugiura Chol Cho Ryoji Okawara Seiji Kaneko 《Plant cell reports》1996,15(10):737-741
Embryogenic callus of Japanese lawngrass (Zoysia japonica Steud.) was induced from sterile mature seeds on LS medium with 5 mg / l of 2,4-D. Embryogenic callus selected visually under microscope was proliferated in liquid N6 medium with amino acids (N6-AA medium). Protoplasts were isolated from suspension cells by the treatment of enzyme mixture containing pectolyase Y-23 and cultured in K8p medium with 2 mg / l of 2,4-D at the density of 106 / ml. Plants were regenerated by transferring the protoplasts derived callus to MS medium and incubating at 28 °C under light for two months. Plantlets were successfully transplanted in the soil.Abbreviations 2,4-D
2,4-dichrolophenoxyacetic acid
- MES
2-(N-Morpholino) ethanesulfonic acid 相似文献
957.
Here we report DNA sequences from mitochondrial cytochrome b gene segments (1,005 base pairs per species) for the extinct woolly mammoth (Mammuthus primigenius) and Steller's sea cow (Hydrodamalis gigas) and the extant Asian elephant (Elephas maximus), the Western Indian manatee (Trichechus manatus), and the hyrax (Procavia capensis). These molecular data have allowed us to construct the phylogeny for the Tethytheria. Our molecular data resolve the trichotomy
between the two species of living elephants and the mammoth and confirm that the mammoth was more closely related to the Asian
elephant than to the African elephant. Our data also suggest that the sea cow–dugong divergence was likely as ancient as the
dugong–manatee split, and it appears to have been much earlier (22 million years ago) than had been previously estimated (4–8
million years ago) by immunological comparison.
Received: 8 August 1996 / Accepted: 30 September 1996 相似文献
958.
John H. Christy Seiji Goshima Patricia R. Y. Backwell Thomas J. Kreuter 《Hydrobiologia》1997,365(1-3):233-239
We saw 79 predatory interactions between a new speciesof monostiliferous, suctorial hoplonemertean and thefiddler crabs Uca musica (77 cases) and U.stenodactylus (2 cases). At an intertidal sand barin the Pacific entrance of the Panama Canal, worms ateabout 0.1% of the adult crab population per day. Themode of attack and the spatial and temporaldistributions of interactions suggest the worm is anambush predator. When struck by a worms sticky,mucous-covered proboscis, crabs produced copious foamfrom their buccal area. Mucous-laden crabs thatescaped, again foamed indicating that the foam maycounteract the mucus. If the attack led to a kill,the struggling crab soon became quiescent, as istypical in other nemertean-prey interactions. Theworm inverted its proboscis, found ingress to thecrabs body and fed. Crabs escaped by autotomizingappendages entwined by the proboscis, by forcefullypulling away and by remaining quiescent, then movingaway when the worm inverted its proboscis and beforeit entered the crab. Immobility, a response to visualpredators, may falsely indicate paralysis to the wormand cause it to invert its proboscis, therebyproviding the crab with an opportunity to escape. This predator-prey interaction seems to incorporategeneralized predator tactics and fortuitous preydefenses that give worms and crabs about an evenchance of success. 相似文献
959.
Involvement of ZO-1 in Cadherin-based Cell Adhesion through Its Direct Binding to α Catenin and Actin Filaments
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Masahiko Itoh Akira Nagafuchi Seiji Moroi Shoichiro Tsukita 《The Journal of cell biology》1997,138(1):181-192
ZO-1, a 220-kD peripheral membrane protein consisting of an amino-terminal half discs large (dlg)-like domain and a carboxyl-terminal half domain, is concentrated at the cadherin-based cell adhesion sites in non-epithelial cells. We introduced cDNAs encoding the full-length ZO-1, its amino-terminal half (N-ZO-1), and carboxyl-terminal half (C-ZO-1) into mouse L fibroblasts expressing exogenous E-cadherin (EL cells). The full-length ZO-1 as well as N-ZO-1 were concentrated at cadherin-based cell–cell adhesion sites. In good agreement with these observations, N-ZO-1 was specifically coimmunoprecipitated from EL transfectants expressing N-ZO-1 (NZ-EL cells) with the E-cadherin/α, β catenin complex. In contrast, C-ZO-1 was localized along actin stress fibers. To examine the molecular basis of the behavior of these truncated ZO-1 molecules, N-ZO-1 and C-ZO-1 were produced in insect Sf9 cells by recombinant baculovirus infection, and their direct binding ability to the cadherin/catenin complex and the actin-based cytoskeleton, respectively, were examined in vitro. Recombinant N-ZO-1 bound directly to the glutathione-S-transferase fusion protein with α catenin, but not to that with β catenin or the cytoplasmic domain of E-cadherin. The dissociation constant between N-ZO-1 and α catenin was ~0.5 nM. On the other hand, recombinant C-ZO-1 was specifically cosedimented with actin filaments in vitro with a dissociation constant of ~10 nM. Finally, we compared the cadherin-based cell adhesion activity of NZ-EL cells with that of parent EL cells. Cell aggregation assay revealed no significant differences among these cells, but the cadherin-dependent intercellular motility, i.e., the cell movement in a confluent monolayer, was significantly suppressed in NZ-EL cells. We conclude that in nonepithelial cells, ZO-1 works as a cross-linker between cadherin/catenin complex and the actin-based cytoskeleton through direct interaction with α catenin and actin filaments at its amino- and carboxyl-terminal halves, respectively, and that ZO-1 is a functional component in the cadherin-based cell adhesion system. 相似文献
960.
Miyakoshi Junji Tsukada Toshihiko Tachiiri Seiji Bandoh Shuji Yamaguchi Ken Takebe Hiraku 《Molecular and cellular biochemistry》1998,181(1-2):191-195
Enhanced expression of neuron derived orphan receptor (NOR-1) gene was observed by exposure of Chinese hamster ovary K1 (CHO-K1) cells to an extremely low frequency magnetic field (ELFMF) of 50 Hz at 400 mT, but not at 5 mT. The enhanced expression, reaching the maximum at 6 h, was transient and reduced to the control level after exposure to 400 mT ELFMF for 24 h. The NOR-1 expression induced by treatment with forskolin and TPA was further enhanced by the simultaneous treatment with 400 mT ELFMF, in which the maximum response was at 3 h. The NOR-1 expression by these treatments was induced more earlier than that by 400 mT ELFMF alone. When cells were treated with an inhibitor of the protein kinase C (calphostin C or crocetin) and Ca2+ entry blockers (nifedipin and dantrolen) during the 400 mT ELFMF exposure, the enhanced NOR-1 expression was not observed. Exposure of CHO-K1 cells to the high-density 400 mT ELFMF may affect the signal transduction in the cells, resulting in the enhanced NOR-1 gene expression. 相似文献