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121.
Murakami T Takada N Harada Y Okuno T Hashimoto M 《Bioscience, biotechnology, and biochemistry》2007,71(5):1230-1235
The filamentous fungus, Lambertella corni-maris (L. corni-maris), a mycoparasite on Monilinia fructigena, produces the antibiotics, lambertellols A (1), B (2), and lambertellin (3), in a substantial amounts under acidic conditions, whereas these antibiotics were hardly detected when the fungus was cultured on a potato-sucrose (PS) medium without added acids. Our investigations also revealed that the host, M. fructigena, changed its surroundings into acidic conditions, suggesting that the acidic conditions acted as kairomones that stimulated the production of 1-3. 相似文献
122.
Mineralization process during acellular cementogenesis in rat molars: a histochemical and immunohistochemical study using fresh-frozen sections 总被引:2,自引:2,他引:0
Yamamoto T Domon T Takahashi S Anjuman KA Fukushima C Wakita M 《Histochemistry and cell biology》2007,127(3):303-311
This study was designed to detect tissue non-specific alkaline phosphatase (TNSALP) by Azo-dye staining, calcium by glyoxal
bis (2-hydroxyanil) (GBHA) staining, bone sialoprotein (BSP) and osteopontin (OPN) by immunoperoxidase staining in developing
rat molars, and also to discuss the mineralization process during acellular cementogenesis. To restrain a reduction in histochemical
and immunohistochemical reactions, fresh-frozen undemineralized sections were prepared. Where the epithelial sheath was intact,
TNSALP reaction was observed in the dental follicle, but not in the epithelial sheath. With the onset of dentin mineralization,
the BSP- and OPN-immunoreactive, initial cementum layer appeared. At this point, cementoblasts had shown intense TNSALP reaction
and GBHA reactive particles (=calcium-GBHA complex) appeared on the root surface. With further development, the reaction of
TNSALP and GBHA became weak on the root surface. Previous studies have shown that the initial cementum is fibril-poor and
that matrix vesicles and calciferous spherules appear on the root surface only during the initial cementogenesis. The findings
mentioned above suggest that: during the initial cementogenesis, cementoblasts release matrix vesicles which result in calciferous
spherules, corresponding to the GBHA reactive particles. The calciferous spherules trigger the mineralization of the initial
cementum. After principal fiber attachment, mineralization advances along collagen fibrils without matrix vesicles. 相似文献
123.
Hishinuma T Suzuki K Saito M Yamaguchi H Suzuki N Tomioka Y Kaneko I Ono M Goto J 《Prostaglandins, leukotrienes, and essential fatty acids》2007,76(6):321-329
We have developed a method for the simultaneous estimation of the levels of the prostanoids 6-keto prostaglandin (PG) Flalpha, PGB2, PGD2, PGE2, PGF2(alpha), PGJ2, and thromboxane (TX) B2 in blood- or serum-containing medium using liquid chromatography-tandem mass spectrometry. These prostanoids and their deuterium derivatives, which were used as internal standards, were subjected to solid-phase extraction using Empore C18 HD disk cartridges and analyzed in the selected reaction-monitoring mode. A linear response curve starting at 10 pg of prostanoid/tube was observed for each prostanoid. The accuracy of the method was demonstrated with samples containing known amounts of the prostanoids. Furthermore, we used this method to analyze the prostanoids produced in mouse bone marrow-derived mast cells stimulated with arachidonic acid, which resulted in the production of PGD2, PGE2, PGF2alpha, and TXB2. The results suggest that this simultaneous quantification method is useful for the analysis of the production of biomedically important prostanoids. 相似文献
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Takanori Yanagi Kenta Ito Akiha Nishihara Reika Minamino Shoko Mori Masayuki Sumida Chikara Hashimoto 《Development, growth & differentiation》2015,57(3):218-231
The dorsal blastopore lip (known as the Spemann organizer) is important for making the body plan in amphibian gastrulation. The organizer is believed to involute inward and migrate animally to make physical contact with the prospective head neuroectoderm at the blastocoel roof of mid‐ to late‐gastrula. However, we found that this physical contact was already established at the equatorial region of very early gastrula in a wide variety of amphibian species. Here we propose a unified model of amphibian gastrulation movement. In the model, the organizer is present at the blastocoel roof of blastulae, moves vegetally to locate at the region that lies from the blastocoel floor to the dorsal lip at the onset of gastrulation. The organizer located at the blastocoel floor contributes to the anterior axial mesoderm including the prechordal plate, and the organizer at the dorsal lip ends up as the posterior axial mesoderm. During the early step of gastrulation, the anterior organizer moves to establish the physical contact with the prospective neuroectoderm through the “subduction and zippering” movements. Subduction makes a trench between the anterior organizer and the prospective neuroectoderm, and the tissues face each other via the trench. Zippering movement, with forming Brachet's cleft, gradually closes the gap to establish the contact between them. The contact is completed at the equator of early gastrulae and it continues throughout the gastrulation. After the contact is established, the dorsal axis is formed posteriorly, but not anteriorly. The model also implies the possibility of constructing a common model of gastrulation among chordate species. 相似文献
128.
Influence of Prostate Stem Cell Antigen Gene Polymorphisms on Susceptibility to Helicobacter pylori‐associated Diseases: A Case‐control Study
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129.
Physiological characterization of anaerobic ammonium oxidizing bacterium ‘Candidatus Jettenia caeni’
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Muhammad Ali Mamoru Oshiki Takanori Awata Kazuo Isobe Zenichiro Kimura Hiroaki Yoshikawa Daisuke Hira Tomonori Kindaichi Hisashi Satoh Takao Fujii Satoshi Okabe 《Environmental microbiology》2015,17(6):2172-2189
To date, six candidate genera of anaerobic ammonium‐oxidizing (anammox) bacteria have been identified, and numerous studies have been conducted to understand their ecophysiology. In this study, we examined the physiological characteristics of an anammox bacterium in the genus ‘Candidatus Jettenia’. Planctomycete KSU‐1 was found to be a mesophilic (20–42.5°C) and neutrophilic (pH 6.5–8.5) bacterium with a maximum growth rate of 0.0020 h?1. Planctomycete KSU‐1 cells showed typical physiological and structural features of anammox bacteria; i.e. 29N2 gas production by coupling of 15NH4+ and 14NO2?, accumulation of hydrazine with the consumption of hydroxylamine and the presence of anammoxosome. In addition, the cells were capable of respiratory ammonification with oxidation of acetate. Notably, the cells contained menaquinone‐7 as a dominant respiratory quinone. Proteomic analysis was performed to examine underlying core metabolisms, and high expressions of hydrazine synthase, hydrazine dehydrogenase, hydroxylamine dehydrogenase, nitrite/nitrate oxidoreductase and carbon monoxide dehydrogenase/acetyl‐CoA synthase were detected. These proteins require iron or copper as a metal cofactor, and both were dominant in planctomycete KSU‐1 cells. On the basis of these experimental results, we proposed the name ‘Ca. Jettenia caeni’ sp. nov. for the bacterial clade of the planctomycete KSU‐1. 相似文献
130.