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11.
The nest site characteristics of the freshwater three-spined stickleback, Gasterosteus aculeatus (form leiurus ), were quantitatively investigated in springs and the main stream of the Yamayoke and the Tsuya River system, central Japan. Most nests (93·4%) were on a muddy or sandy substratum, at depths of 10–40 cm (84·3%), in water velocities less than 15 cm s−1 (76·2%) and in the temperature range of 14 to 16° C (82·7%), Spring-fed localities provided more of these conditions than the main stream channel and hence contained more potential nesting areas. Thus, they were utilized by male sticklebacks both temporally (prolonged breeding season) and spatially (more nest sites). 相似文献
12.
Klas Ostwald Masami Hayashi Megumi Nakamura †Seiichi Kawashima 《Journal of neurochemistry》1994,63(3):1069-1076
Abstract: Rabbits were subjected to hypoxia (5% O2 ) for up to 90 min and allowed to recover for a maximum of 4 days. Hippocampus homogenate was assayed for fodrin breakdown product (BDP). After separation into a nuclear and mitochondrial fraction (NMF), a membrane and microsomal fraction (MMF), and a cytosolic fraction (CF), samples were assayed for μ-calpain, m-calpain, and calpastatin immunoreactivity. Calpain and calpastatin immunoreactivity decreased in the NMF and CF but increased in the MMF during hypoxia and short-term recovery. This translocation occurred in parallel with the increase in fodrin BDP. Because the increase in the MMF was not large enough to explain the decrease in the other two fractions, it was assumed that the translocation and activation was accompanied by a reduction in the total amounts of calpains and calpastatin. Glucocorticoid pretreatment (beta-methasone, 0.4 mg × kg−1 × day−1 ) for 7 days produced a decrease in the ratio of activated μ-calpain in all three fractions in nearly all samples before, during, and after hypoxia, compared with untreated animals. Glucocorticoid pretreatment also prevented the increase in fodrin BDP that occurred in untreated animals during hypoxia and short-term recovery, indicating impairment of calpain activation. 相似文献
13.
Non-systemic expression of a stress-responsive maize polyubiquitin gene (Ubi-1) in transgenic rice plants 总被引:6,自引:0,他引:6
Ikuyoshi Takimoto Alan H. Christensen Peter H. Quail Hirofumi Uchimiya Seiichi Toki 《Plant molecular biology》1994,26(3):1007-1012
We have used the promoter, 1st exon and 1st intron of the maize polyubiquitin gene (Ubi-1) for rice transformation experiments and revealed the characteristic expression of Ubi-1 gene: (1) Ubi-1 gene is not regulated systemically but rather individual cells respond independently to the heat or physical stress; (2) Ubi-1 gene changes its tissue-specific expression in response to stress treatment; (3) the expression of Ubi-1 gene is dependent on cell cycle. 相似文献
14.
Seiichi Ueda 《Mycoscience》1994,35(3):287-290
A new species ofCercophora, isolated from river sediment collected from Sakai River in Nagasaki Prefecture, Japan, is described and illustrated. It is distinguished from the other knwon species by the morphology of its ascomatal peridium and ascospores, and by itsChrysosporium-like anamorph. 相似文献
15.
Kazuhito Hisatsune Takehiro Iguchi Yuji Haishima Norihiko Tamura Seiichi Kondo 《Microbiology and immunology》1993,37(2):143-147
The chemical properties of a lipopolysaccharide (LPS) isolated from a new O-antigenic form (O13) of Vibrio parahaemolyticus were investigated. The LPS contained glucose, galactose, L -glycero-D -manno-heptose and glucosamine. 2-Keto-3-deoxy-octonate (KDO) was not detected in the LPS by the periodate-thiobarbituric acid test (Weissbach's reaction) under conventional hydrolysis conditions. Instead, phosphorylated KDO (X1 and X2) was found in its strong-acid hydrolysate. This sugar composition was identical to that of V. parahaemolyticus O3, O5 and O11 LPS, indicating that, based on the sugar composition, O13 LPS belongs to Chemotype III to which O3, O5 and O11 belong. In addition, structural study demonstrated the presence of KDO 4-phosphate in its inner-core region. 相似文献
16.
The concanavalin A staining of cellular glycoproteins and thedirect analysis of their sugar chains released by hydrazinolysisrevealed that the processing of N-linked sugar chains of someglycoproteins is suppressed by exposure of mouse monocytoidcells P388D1 to dimethyl sulphoxide, which can induce Fc receptor-mediatedphagocytosis. To elucidate the significance of altered glycosylationin inducing phagocytosis, the effects of exposure of the cellsto processing inhibitors (swainsonine and castanospermine) wereexamined and it was found that the cells are induced to acquirean ability to ingest IgG-coated sheep red blood cells, dependingon the dose of the inhibitors and incubation time. Analysisof the N-linked sugar chains liberated from cellular glycoproteinsby hydrazinolysis confirmed that the processing of the sugarchains is suppressed by the two inhibitors as expected. Sinceno significant alteration was induced in protein synthesis andDNA synthesis after exposure to the inhibitors, it is suggestedthat the altered glycosylation of cellular glycoproteins mayhave some direct role in the induction of Fc receptor-mediatedphagocytosis. The inhibitors did not affect the binding of theIgG-coated red blood cells to Fc receptors on the cells, non-specificphagocytosis of latex beads, and the contents of lysosomal enzymes,ß-glucuronidase and acid phosphatase. These resultssuggest that the glycosylation status of cellular glycoproteinsinfluences some specific processes involved in the ingestionof the ligands bound to Fc receptors. castanospermine macrophages phagocytosis swainsonine 相似文献
17.
Effects of in vivo exposure with fenvalerate, esfenvalerate andDDT on hepatic gap junctional intercellular communication (GJIC) in Sprague-Dawley (SD) rats were examined by in vivolin vitro dye-transfer assay and by immunohistochemical staining of connexin 32 (C×32, major liver gap junction protein). Fenvalerate (75 mg/kg/day), esfenvalerate (25 mg/kg/day), DDT (50 mg/kg/day) and corn oil (vehicle control, 5mllkglday) were administered orally once a day. Animals were killed at weeks 1, 2, 4 and 6 after starting the experiment. In the fenvalerate- and esfenvalerate-groups, no compound-related changes in GJIC and C×32 expression were observed. On the contrary, in the DDT-group, average sizes of the dye spread after injection of Lucifer Yellow decreased at weeks 1, 2 and 4, and the area per GJ spot shown by C×32-immunohistochemical staining decreased at weeks 4 and 6. It is concluded that neither fenvalerate nor esfenvalerate inhibits hepatic GJIC with in vivo exposure. 相似文献
18.
T. Ito Naoko Udaka Yoshiaki Inayama Hitoshi Kitamura Masayoshi Kanisawa 《Histochemistry and cell biology》1997,109(1):67-73
We have examined the distribution of calcium-binding proteins (CaBPs) in adult and fetal lungs of Syrian golden hamsters
(Mesocricetus auratus) using immunostaining with confocal laser microscopy and electron microscopy. Single and grouped (neuroepithelial body; NEB)
endocrine cells were distributed from bronchi to alveolar ducts in the adult lung. Serial frozen sections immunostained for
CaBPs in combination with immunostaining for endocrine markers such as calcitonin gene-related peptide, serotonin, PGP9.5,
and synaptophysin revealed that positive immunostaining for calbindin-D28K (CB-D28K) was seen in single endocrine cells and NEBs. However, other so-called EF-hand family CaBPs, parvalbumin and calretinin,
were not detected. Electron microscopically, positive immunoreaction for CB-D28K was mainly in the organelle-free cytoplasmic
matrix of endocrine cells, and partly in nuclei and associated with secretory granules and endoplasmic reticulum. In fetal
developing lungs, endocrine cells appeared first on gestational day 13, and they were positive for all the endocrine markers
used. However, pulmonary endocrine cells were positively immunostained for CB-D28K from gestational days 15 and 16 onward.
In summary, our observations suggest that CB-D28K is a useful marker for endocrine cells of the lung, and CB-D28K could function
as a mediator of endocrine stimulation or calcium homeostasis in pulmonary endocrine cells.
Accepted: 17 June 1997 相似文献
19.
Zhang Ying; Iwasa Tatsuo; Tsuda Motoyuki; Kobata Akira; Takasaki Seiichi 《Glycobiology》1997,7(8):1153-1158
The N-linked sugar chains were liberated as oligosaccha-ridesfrom octopus rhodopsin by hydrazinolysis. Most of the oligosaccharideswere neutral, and separated into two major components by columnchromatography using immobilized lectins and Bio-Gel P-4. Structuralanalysis of the one major component by sequential exoglycosidasedigestion, chemical fragmentation in combination with meth-ylationanalysis revealed that it is a nonasaccharide; Man16(Gaiβ13GlcNAcβ12Man13)Manβ14GlcNAcβ14(Galβ14Fuc16)GlcNAcThis structure is quite unique in that a novel galactosylatedfucose residue is attached to the reducing terminal N-acetyl-glucosamineresidue. galactosylated Fuc N-linked sugar chain novel structure octopus rhodopsin 相似文献
20.
Yoshiaki Inayama Izumi Tomiyama Hitoshi Kitamura Yukio Nakatani Takaaki Ito Akinori Nozawa Yasuhiro Usuda Masayoshi Kanisawa 《Histochemistry and cell biology》1995,104(3):191-198
The purpose of this study was to investigate alkaline phosphatase (ALPase) reactivity in rabbit airway epithelial cells. Acetone-fixed, methyl benzoate and xylene-cleared (AMeX-treated) paraffin sections of trachea, bronchus, and lung tissue were stained by an azo dye coupling method for ALPase and examined by light microscopy. Electron histochemical staining was also performed in order to study the sensitivity and specificity of reactivity in each cell type. ALPase reactivity at the light microscopic level was observed exclusively in trachco-bronchial basal cells, and not in bronchiolar basal cells. By electron microscopy, ALPase reactivity was noted in 97.9% of basal cells in the trachea, 97.0% of basal cells in the bronchus, and 94.5% of basal cells and 15.4% of Clara cells in the bronchiole. This was also true for dispersed tracheal epithelial cells. Reactivity was rarely observed in ciliated cells, non-goblet-type secretory cells, and undetermined cells. The reactivity was heatlabile, levamisole-sensitive, and of a non-specific type. These findings indicate that basal cells of rabbit trachea and bonchus have fairly high specificity for ALPase of a non-specific isozyme (92.2% and 95.6%, respectively). Therefore, ALPase is considered to be a useful marker for these cells. 相似文献