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971.
Dhungana Sandra Madhyastha Radha Madhyastha Harishkumar Nakajima Yuichi Omura Sayuri Maruyama Masugi 《Phytomedicine》2010,17(1):42-46
Urokinase plasminogen activator (uPA) system, comprising of uPA, its receptor uPAR and inhibitor, type 1 plasminogen activator inhibitor (PAI-1), plays a vital role in various biological processes involving extracellular proteolysis, fibrinolysis, cell migration and proliferation. The timely occurence of these processes are essential for normal wound healing. This study examines the regulation of uPA and PAI-1 by a natural polyphenol-rich compound, grape seed extract (GSE). GSE is reported to have beneficial effects in promoting wound healing. Fibroblast cells exposed to different doses of GSE for 18 hours were processed for further studies such as ELISA, RT-PCR, western blotting, fibrinolytic assay, cell surface plasmin activity assay and in vitro wound healing assay. GSE treatment caused a significant downregulation of uPA and PAI-1 expression, both at the RNA and protein levels. ELISA also revealed a dose-dependent decrease in uPA and PAI-1 activities. Functional significance of the downregulation was evident in decreased fibrinolytic activity, concomittant with decreased cell-surface plasmin activity. In vitro wound healing studies showed that GSE also retarded the migration of cells towards the wounded region. 相似文献
972.
Hirokazu kasahara Masahide Shiwa Yuichi Takeuchi Mitsuhiro Yamada 《Journal of plant research》1995,108(1):59-64
The elongation growth of the hypocotyls of radish and cucumber seedlings was examined under hypergravity in a newly developed
centrifuge (Kasaharaet al. 1995). The effects of hypergravity on elongation growth differed between the two species. The rate of elongation of radish
hypocotyls was reduced under basipetal hypergravity (H+20g) but not under acropetal hypergravity (H-13g), as compared to growth under the control conditions (C+1g and C-1g). In cucumber hypocotyls, elongation growth was inhibited not only by basipetal but also by acropetal hypergravity. Under
these conditions, the reduction in the elongation growth of both radish and cucumber hypocotyls was accompanied by an increase
in their thickness. Although no distinct differences in relative composition of neutral sugars were found, the amounts of
cell-wall components (pectic substances, hemicelluloses and cellulose) per unit length of hypocotyls were increased by exposure
to hypergravity. 相似文献
973.
Yuichi Hashimoto 《Biochemical and biophysical research communications》2009,389(1):95-99
Humanin (HN) inhibits Alzheimer’s disease (AD)-relevant neuronal death and dysfunction, by interacting with a receptor (s) involving ciliary neurotrophic factor receptor α (CNTFR), WSX-1, and gp130. It remains unknown whether this complex is the sole HN receptor that mediates HN-induced anti-AD activity. We here report that an alternatively spliced WSX-1 isoform, encoding an extracellular 270-amino-acid region of WSX-1 with cytokine-binding regions (named soluble WSX-1; sWSX-1), is expressed in neuronal cells lacking function of full-length WSX-1 and enables HN to rescue AD-relevant death. This result suggests that CNTFR/soluble WSX-1/gp130 behaves as an alternative functional HN receptor. 相似文献
974.
Yuichi Yamane Takashi Mikami Katsuya Higashida Toshihide Kakizono Naomichi Nishio 《Biotechnology Techniques》1996,10(7):529-534
Summary Near infrared reflectance spectroscopy (NIR) was employed to estimate the concentrations of cells, astaxanthin and glucose in the culture broth of Phaffia rhodozyma. The culture broth (119 samples) was directly subjected for NIR analysis without any pretreatment. When the data obtained by NIR were compared with those obtained by conventional methods, high correlation coefficients were obtained: 0.98 for cells, 0.99 for astaxanthin and 0.94 for glucose. These results suggest that NIR analysis, which is very simple and requires only 3 to 5 mm for a sample, is applicable to monitor P. rhodozyma cultures. 相似文献
975.
Munetaka Sugiyama Edward C. Yeung Yuichi Shoji Atsushi Komamine 《Journal of plant research》1995,108(3):351-361
In cultures of isolated mesophyll cells ofZinnia elegans, transdifferentiation into tracheary elements is induced by a combination of auxin and cytokinin and is blocked by inhibitors
of DNA synthesis and poly (ADP-ribose) synthesis. During transdifferentiation, a very low level of synthesis of nuclear DNA
was found in some cultured cells by microautoradiography after pulse-labeling with [3H]thymidine. Density profiles of nuclear DNA that had been double-labeledin vivo with bromodeoxyuridine (BrdU) and [3H]thymidine indicated that this DNA synthesis was repair-type synthesis. The sedimentation velocity of nucleoids increased
during the culture of isolated mesophyll cells and the increase was dependent on phytohormones. This phenomenon may reflect
the rejoining of DNA strand breaks after repair-type DNA synthesis during transdifferentiation. Treatment of cells with inhibitors
of DNA synthesis or of poly(ADP-ribose) synthesis prevented the increase in the sedimentation velocity of nucleoids. The data
suggest the involvement of DNA-repair events in the transdifferentiation of mesophyll cells into tracheary elements. 相似文献
976.
977.
Yi Cao Roger A. Chastain Emiley A. Eloe Yuichi Nogi Chiaki Kato Douglas H. Bartlett 《Applied and environmental microbiology》2014,80(1):54-60
The diversity of deep-sea high-pressure-adapted (piezophilic) microbes in isolated monoculture remains low. In this study, a novel obligately psychropiezophilic bacterium was isolated from seawater collected from the Puerto Rico Trench at a depth of ∼6,000 m. This isolate, designated YC-1, grew best in a nutrient-rich marine medium, with an optimal growth hydrostatic pressure of 50 MPa (range, 20 to 70 MPa) at 8°C. Under these conditions, the maximum growth rate was extremely slow, 0.017 h−1, and the maximum yield was 3.51 × 107 cells ml−1. Cell size and shape changed with pressure, shifting from 4.0 to 5.0 μm in length and 0.5 to 0.8 μm in width at 60 MPa to 0.8- to 1.0-μm diameter coccoid cells under 20 MPa, the minimal pressure required for growth. YC-1 is a Gram-negative, facultatively anaerobic heterotroph. Its predominant cellular fatty acids are the monounsaturated fatty acids (MUFAs) C16:1 and C18:1. Unlike many other psychropiezophiles, YC-1 does not synthesize any polyunsaturated fatty acids (PUFAs). Phylogenetic analysis placed YC-1 within the family of Oceanospirillaceae, closely related to the uncultured symbiont of the deep-sea whale bone-eating worms of the genus Osedax. In common with some other members of the Oceanospirillales, including those enriched during the Deepwater Horizon oil spill, YC-1 is capable of hydrocarbon utilization. On the basis of its characteristics, YC-1 appears to represent both a new genus and a new species, which we name Profundimonas piezophila gen. nov., sp. nov. 相似文献
978.
Kaori Yamada Yuichi Kawanishi Akinori Yamada Gaku Tokuda Raj Deep Gurung Takeshi Sasaki Yumiko Nakajima Hideaki Maekawa 《Genetica》2014,142(2):149-160
Mariner-like elements (MLEs) have been isolated from various eukaryotic genomes and they are divided into 15 subfamilies, including main five subfamilies: mauritiana, cecropia, mellifera/capitata, irritans, and elegans/briggsae. In the present study, MLEs belonging to mellifera subfamily were isolated from various spiders and insects (Hymenoptera and Lepidoptera) inhabiting the South-West Islands of Japan and neighboring regions. MLEs isolated from 15 different species formed a distinct novel cluster in mellifera subfamily. MLEs obtained from three different species [i.e., the bee Amegilla senahai subflavescens (Amsmar1), the wasp Campsomeris sp. (Casmar1), and the swallowtail butterfly Pachliopta aristolochiae (Paamar1)] contained an intact open reading frame that encoded a putative transposase. These transposases exhibited high similarity of 97.9 % among themselves. In case of Casmar1, the presence of an intact ORF was found in high frequencies (i.e., 11 out of 12 clones). In addition, these transposases also showed the presence of a terminal inverted repeat-binding motif, DD(34)D and two highly conserved amino acid motifs, (W/L)(I/L)PHQL and YSP(D/N)L(A/S)P. These two motifs differed from previously known motifs, WVPHEL and YSPDLAP. MLEs isolated from these three different species may have been inserted into their genomes by horizontal transfer. Furthermore, the presence of an intact ORF suggests that they are still active in habitats along these isolated islands. 相似文献
979.
Nikolai Lorenzen S?ren B. Nielsen Yuichi Yoshimura Brian S. Vad Camilla Bertel Andersen Cristine Betzer J?rn D. Kaspersen Gunna Christiansen Jan S. Pedersen Poul Henning Jensen Frans A. A. Mulder Daniel E. Otzen 《The Journal of biological chemistry》2014,289(31):21299-21310
Oligomeric species of various proteins are linked to the pathogenesis of different neurodegenerative disorders. Consequently, there is intense focus on the discovery of novel inhibitors, e.g. small molecules and antibodies, to inhibit the formation and block the toxicity of oligomers. In Parkinson disease, the protein α-synuclein (αSN) forms cytotoxic oligomers. The flavonoid epigallocatechin gallate (EGCG) has previously been shown to redirect the aggregation of αSN monomers and remodel αSN amyloid fibrils into disordered oligomers. Here, we dissect EGCG''s mechanism of action. EGCG inhibits the ability of preformed oligomers to permeabilize vesicles and induce cytotoxicity in a rat brain cell line. However, EGCG does not affect oligomer size distribution or secondary structure. Rather, EGCG immobilizes the C-terminal region and moderately reduces the degree of binding of oligomers to membranes. We interpret our data to mean that the oligomer acts by destabilizing the membrane rather than by direct pore formation. This suggests that reduction (but not complete abolition) of the membrane affinity of the oligomer is sufficient to prevent cytotoxicity. 相似文献
980.
Wataru Nunomura Philippe Gascard Hideki Wakui Yuichi Takakuwa 《Biochemical and biophysical research communications》2014
Membrane skeletal protein 4.1R80 plays a key role in regulation of erythrocyte plasticity. Protein 4.1R80 interactions with transmembrane proteins, such as glycophorin C (GPC), are regulated by Ca2+-saturated calmodulin (Ca2+/CaM) through simultaneous binding to a short peptide (pep11; A264KKLWKVCVEHHTFFRL) and a serine residue (Ser185), both located in the N-terminal 30 kDa FERM domain of 4.1R80 (H·R30). We have previously demonstrated that CaM binding to H·R30 is Ca2+-independent and that CaM binding to H·R30 is responsible for the maintenance of H·R30 β-sheet structure. However, the mechanisms responsible for the regulation of CaM binding to H·R30 are still unknown. To investigate this, we took advantage of similarities and differences in the structure of Coracle, the Drosophila sp. homologue of human 4.1R80, i.e. conservation of the pep11 sequence but substitution of the Ser185 residue with an alanine residue. We show that the H·R30 homologue domain of Coracle, Cor30, also binds to CaM in a Ca2+-independent manner and that the Ca2+/CaM complex does not affect Cor30 binding to the transmembrane protein GPC. We also document that both H·R30 and Cor30 bind to phosphatidylinositol-4,5 bisphosphate (PIP2) and other phospholipid species and that that PIP2 inhibits Ca2+-free CaM but not Ca2+-saturated CaM binding to Cor30. We conclude that PIP2 may play an important role as a modulator of apo-CaM binding to 4.1R80 throughout evolution. 相似文献