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81.
Yoriko Yukitatsu Masaki Hata Koji Yamanegi Naoko Yamada Hideki Ohyama Keiji Nakasho Yusuke Kojima Hideki Oka Kenzo Tsuzuki Masafumi Sakagami Nobuyuki Terada 《Cell and tissue research》2013,352(3):647-657
VE-cadherin and claudin-5 are major components of adherens and tight junctions of vascular endothelial cells and a decrease in their expression and an increase in the tyrosine-phosphorylation of VE-cadherin are associated with an increase in endothelial paracellular permeability. To clarify the mechanism underlying the development of edema in nasal polyps, we studied these molecules in polyp microvessels. Normal inferior turbinate mucosal tissues and nasal polyps from patients treated with or without glucocorticoid were stained for VE-cadherin or claudin-5 and CD31 by a double-immunofluorescence method and the immunofluorescence intensities were graded 1–3 with increasing intensity. To correct for differences in fluorescence intensity attributable to a different endothelial area being exposed in a section or to the thickness of a section, the relative immunofluorescence intensity was estimated by dividing the grade of VE-cadherin or claudin-5 by that of CD31 in each microvessel. Tyrosine-phosphorylation of VE-cadherin was examined by Western blot analysis. The relative intensities of VE-cadherin and claudin-5 in the CD31-positive microvessels significantly decreased in the following order; inferior turbinate mucosa, treated polyps and untreated polyps. The ratio of tyrosine-phosphorylated VE-cadherin to VE-cadherin was significantly higher in untreated polyps than in the inferior turbinate mucosa and treated polyps, between which no significant difference in the ratio was seen. Thus, in nasal polyps, the barrier function of endothelial adherens and tight junctions is weakened, although glucocorticoid treatment improves this weakened barrier function. 相似文献
82.
Yufeng Li Yusuke Miyanari Kenjiro Shirane Hirohisa Nitta Takeo Kubota Hirofumi Ohashi Akimitsu Okamoto Hiroyuki Sasaki 《Nucleic acids research》2013,41(19):e186
Methylation-specific fluorescence in situ hybridization (MeFISH) was developed for microscopic visualization of DNA methylation status at specific repeat sequences in individual cells. MeFISH is based on the differential reactivity of 5-methylcytosine and cytosine in target DNA for interstrand complex formation with osmium and bipyridine-containing nucleic acids (ICON). Cell nuclei and chromosomes hybridized with fluorescence-labeled ICON probes for mouse major and minor satellite repeats were treated with osmium for crosslinking. After denaturation, fluorescent signals were retained specifically at satellite repeats in wild-type, but not in DNA methyltransferase triple-knockout (negative control) mouse embryonic stem cells. Moreover, using MeFISH, we successfully detected hypomethylated satellite repeats in cells from patients with immunodeficiency, centromeric instability and facial anomalies syndrome and 5-hydroxymethylated satellite repeats in male germ cells, the latter of which had been considered to be unmethylated based on anti-5-methylcytosine antibody staining. MeFISH will be suitable for a wide range of applications in epigenetics research and medical diagnosis. 相似文献
83.
Background and Aims
Globally, conifer dominance is restricted to nutient-poor habitats in colder, drier or waterlogged environments, probably due to competition with angiosperms. Analysis of canopy structure is important for understanding the mechanism of plant coexistence in relation to competition for light. Most conifers are shade intolerant, and often have narrow, deep, conical crowns. In this study it is predicted that conifer-admixed forests have less distinct upper canopies and more undulating canopy surfaces than angiosperm-dominated forests.Methods
By using a ground-based, portable light detection and ranging (LIDAR) system, canopy structure was quantified for old-growth evergreen rainforests with varying dominance of conifers along altitudinal gradients (200–3100 m a.s.l.) on tropical and sub-tropical mountains (Mount Kinabalu, Malaysian Borneo and Yakushima Island, Japan) that have different conifer floras.Key Results
Conifers dominated at higher elevations on both mountains (Podocarpaceae and Araucariaceae on Kinabalu and Cupressaceae and Pinaceae on Yakushima), but conifer dominance also varied with soil/substrate conditions on Kinabalu. Conifer dominance was associated with the existence of large-diameter conifers. Forests with higher conifer dominance showed a canopy height profile (CHP) more skewed towards the understorey on both Kinabalu and Yakushima. In contrast, angiosperm-dominated forests had a CHP skewed towards upper canopy, except for lowland dipterocarp forests and a sub-alpine scrub dominated by small-leaved Leptospermum recurvum (Myrtaceae) on Kinabalu. Forests with a less dense upper canopy had more undulating outer canopy surfaces. Mixed conifer–angiosperm forests on Yakushima and dipterocarp forests on Kinabalu showed similar canopy structures.Conclusions
The results generally supported the prediction, suggesting that lower growth of angiosperm trees (except L. recurvum on Kinabalu) in cold and nutrient-poor environments results in a sparser upper canopy, which allows shade-intolerant conifers to co-occur with angiosperm trees either as emergents or as codominants in the open canopy. 相似文献84.
Widyanto Dwi Nugroho Satoshi Nakaba Yusuke Yamagishi Shahanara Begum Sri Nugroho Marsoem Jae-Heung Ko Hyun-O Jin Ryo Funada 《Annals of botany》2013,112(7):1321-1329
Background and Aims
Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus.Methods
Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems.Key Results
Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells.Conclusions
The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism. 相似文献85.
Satoru Kontani Eiichiro Nagata Tsuyoshi Uesugi Yusuke Moriya Natsuko Fujii Toshio Miyata Shunya Takizawa 《Neurochemical research》2013,38(12):2588-2594
Hypoxia-inducible factor 1 (HIF-1) is regulated by the oxygen-dependent hydroxylation of proline residues by prolyl hydroxylases (PHDs). We recently developed a novel PHD inhibitor, TM6008, that suppresses the activity of PHDs, inducing continuous HIF-1α activation. In this study, we investigated how TM6008 affects cell survival after hypoxic conditions capable of inducing HIF-1α expression and how TM6008 regulates PHDs and genes downstream of HIF-1α. After SHSY-5Y cells had been subjected to hypoxia, TM6008 was added to the cell culture medium under normoxic conditions. Apoptotic cell death was significantly augmented just after the hypoxic conditions, compared with cell death under normoxic conditions. Notably, when TM6008 was added to the media after the cells had been subjected to hypoxia, the expression level of HIF-1α increased and the number of cell deaths decreased, compared with the results for cells cultured in media without TM6008 after hypoxia, during the 7-day incubation period under normoxic conditions. Moreover, the protein expression levels of heme oxygenase 1, erythropoietin, and glucose transporter-3, which were genes downstream of HIF-1α, were elevated in media to which TM6008 had been added, compared with media without TM6008, during the 7-day incubation period under normoxic conditions. However, the protein expression levels of PHD2 and p53 which suppressed cell proliferation were suppressed in the media to which TM6008 had been added. Thus, TM6008, which suppresses the protein expressions of PHD2 and p53, might play an important role in cell survival after hypoxic conditions, with possible applications as a new compound for treatment after ischemic stroke. 相似文献
86.
Kazuhiro Shiozaki Kazuki Takeshita Mako Ikeda Asami Ikeda Yusuke Harasaki Masaharu Komatsu Shoji Yamada Kazunori Yamaguchi Taeko Miyagi 《Biochimie》2013
Mammalian Neu3 sialidases are involved in various biological processes, such as cell death and differentiation, through desialylation of gangliosides. The enzymatic profile of Neu3 seems to be highly conserved from birds to mammals. In fish, the functional properties of Neu3 sialidase are not clearly understood, with the partial exception of the zebrafish form. To cast further light on the molecular evolution of Neu3 sialidase, we identified the encoding genes in the medaka Oryzias latipes and investigated the properties of the enzyme. PCR amplification using medaka brain cDNA allowed identification of two novel medaka Neu3 genes, neu3a and neu3b. The YRIP, VGPG motif and Asp-Box, characteristic of consensus motifs of sialidases, were well conserved in the both medaka Neu3 sialidases. When each gene was transfected into HEK293 to allow cell lysates for the use of enzymatic characterization, two Neu3 sialidases showed strict substrate specificity toward gangliosides, similar to mammalian Neu3. The optimal pH values were at pH 4.2 and pH 4.0, respectively, and neu3b in particular showed a broad optimum. Immunofluorescence assays indicated neu3a localization at plasma membranes, while neu3b was found in cytosol. The tissue distribution of two genes was then investigated by estimation of mRNA expression and sialidase activity, both being dominantly expressed in the brain. In neu3a gene-transfected neuroblastoma cells, the enzyme was found to positively regulate retinoic acid-induced differentiation with the elongation of axon length. On the other hand, neu3b did not affect neurite formation. These results and phylogenetic analysis suggested that the medaka neu3a is an evolutionally conserved sialidase with regard to enzymatic properties, whereas neu3b is likely to have originally evolved in medaka. 相似文献
87.
88.
In general, transferases undergo large structural changes and sequester substrate molecules, to shield them from water. By contrast, hydrolases exhibit only small structural changes, and expose substrate molecules to water. However, some hydrolases deeply bury their substrates within the proteins. To clarify the relationship between substrate‐shielding and enzymatic functions, we investigated 70 representative hydrolase structures, and examined the relative accessible surface areas of their substrates. As compared to the hydrolases employing the single displacement reaction, the hydrolases employing the double displacement reaction bury the substrate within the proteins. The exo hydrolases display significantly more substrate‐shielding from water than the endo hydrolases. It suggests that the substrate‐shielding is related to the chemical reaction mechanism of the hydrolases and the substrate specificity. Proteins 2013; © 2012 Wiley Periodicals, Inc. 相似文献
89.
Sun Hee Choi Yuka Hagiwara-Komoda Kenji S. Nakahara Go Atsumi Ryoko Shimada Yusuke Hisa Satoshi Naito Ichiro Uyeda 《Journal of virology》2013,87(13):7326-7337
In pea carrying cyv1, a recessive gene for resistance to Clover yellow vein virus (ClYVV), ClYVV isolate Cl-no30 was restricted to the initially infected cells, whereas isolate 90-1 Br2 overcame this resistance. We mapped the region responsible for breaking of cyv1-mediated resistance by examining infection of cyv1 pea with chimeric viruses constructed from parts of Cl-no30 and 90-1 Br2. The breaking of resistance was attributed to the P3 cistron, which is known to produce two proteins: P3, from the main open reading frame (ORF), and P3N-PIPO, which has the N-terminal part of P3 fused to amino acids encoded by a small open reading frame (ORF) called PIPO in the +2 reading frame. We introduced point mutations that were synonymous with respect to the P3 protein but nonsynonymous with respect to the P3N-PIPO protein, and vice versa, into the chimeric viruses. Infection of plants with these mutant viruses revealed that both P3 and P3N-PIPO were involved in overcoming cyv1-mediated resistance. Moreover, P3N-PIPO quantitatively affected the virulence of Cl-no30 in cyv1 pea. Additional expression in trans of the P3N-PIPO derived from Cl-no30, using White clover mosaic virus as a vector, enabled Cl-no30 to move to systemic leaves in cyv1 pea. Susceptible pea plants infected with chimeric ClYVV possessing the P3 cistron of 90-1 Br2, and which were therefore virulent toward cyv1 pea, accumulated more P3N-PIPO than did those infected with Cl-no30, suggesting that the higher level of P3N-PIPO in infected cells contributed to the breaking of resistance by 90-1 Br2. This is the first report showing that P3N-PIPO is a virulence determinant in plants resistant to a potyvirus. 相似文献
90.
Yusuke Morita Naomichi Ogihara Takashi Kanai Hiromasa Suzuki 《American journal of physical anthropology》2013,151(4):658-666
Three‐dimensional geometric morphometric techniques have been widely used in quantitative comparisons of craniofacial morphology in humans and nonhuman primates. However, few anatomical landmarks can actually be defined on the neurocranium. In this study, an alternative method is proposed for defining semi‐landmarks on neurocranial surfaces for use in detailed analysis of cranial shape. Specifically, midsagittal, nuchal, and temporal lines were approximated using Bezier curves and equally spaced points along each of the curves were defined as semi‐landmarks. The shortest paths connecting pairs of anatomical landmarks as well as semi‐landmarks were then calculated in order to represent the surface morphology between landmarks using equally spaced points along the paths. To evaluate the efficacy of this method, the previously outlined technique was used in morphological analysis of sexual dimorphism in modern Japanese crania. The study sample comprised 22 specimens that were used to generate 110 anatomical semi‐landmarks, which were used in geometric morphometric analysis. Although variations due to sexual dimorphism in human crania are very small, differences could be identified using the proposed landmark placement, which demonstrated the efficacy of the proposed method. Am J Phys Anthropol 151:658–666, 2013. © 2013 Wiley Periodicals, Inc. 相似文献