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961.
Tamori M Saha AK Matsuno A Noskor SC Koizumi O Kobayakawa Y Nakajima Y Motokawa T 《Proceedings. Biological sciences / The Royal Society》2007,274(1623):2279-2285
Stichopin, a 17-amino acid peptide isolated from a sea cucumber, affects the stiffness change of the body-wall catch connective tissues and the contraction of the body-wall muscles. The localization of stichopin in sea cucumbers was studied by indirect immunohistochemistry using antiserum against stichopin. Double staining was performed with both stichopin antiserum and 1E11, the monoclonal antibody specific to echinoderm nerves. A stichopin-like immunoreactivity (stichopin-LI) was exclusively found in the connective tissues of various organs. Many fibres and cells with processes were stained by both the anti-stichopin antibody and 1E11. They were found in the body-wall dermis and the connective tissue layer of the cloacae and were suggested to be connective tissue-specific nerves. Oval cells with stichopin-LI (OCS) without processes were found in the body-wall dermis, the connective tissue sheath of the longitudinal body-wall muscles, the connective tissue layer of the tube feet and tentacles, and the connective tissue in the radial nerves separating the ectoneural part from the hyponeural part. Electron microscopic observations of the OCSs in the radial nerves showed that they were secretory cells. The OCSs were located either near the well-defined neural structures or near the water-filled cavities, such as the epineural sinus and the canals of the tube feet. The location near the water-filled cavities might suggest that stichopin was secreted into these cavities to function as a hormone. 相似文献
962.
Salmonella were isolated from 106 (0.032%) of 331,644 fecal samples from food handlers, and from 144 of 11,478 fecal samples from symptomatic patients in Japan to determine the incidence and features of Salmonella serovars among food handlers. S. enterica subspecies enterica serovar Infantis (S. serovar Infantis) was the dominant serovar (accounting for 48.1%), followed by S. serovar Corvallis, which showed poor genetic diversity, and S. serovar Enteritidis among food handlers. The former two serovars were not dominant among symptomatic patients. The present study demonstrates the need for education on the sanitary handling of chicken eggs and chicken meat, which are possible infectious sources of these Salmonella serovars. 相似文献
963.
964.
Eleven 16S rRNA gene clone libraries including 34 archaeal and 72 bacterial phylotypes were constructed from total 708 clones
of hydrothermal vent prokaryotes trapped by 0.2- and 0.1-μm-pore-size filters. Crenarchaeota and Proteobacteria phylotypes
dominated the archaeal and bacterial populations, respectively. Novel unaffiliated phylotypes occurred only in the 0.1-μm-trapped
populations. 相似文献
965.
966.
Taro Tsurukai Naoyuki Takahashi Eijiro Jimi Ichiro Nakamura Nobuyuki Udagawa Katsumi Nogimori Makoto Tamura Tatsuo Suda 《Journal of cellular physiology》1998,177(1):26-35
Osteoclasts are formed in cocultures of mouse calvarial cells and hematopoietic cells in the presence of osteotropic factors such as 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], parathyroid hormone (PTH) and prostaglandin E2 (PGE2). We isolated osteoclast precursors (OCPs) from the coculture and examined their characteristics. After coculture for 7 days of mouse calvarial cells and bone marrow cells in the absence of osteotropic factors, hematopoietic cells were recovered and applied to a Sephadex G-10 column. Cells which passed through the column were collected as OCPs. When OCPs were cultured on calvarial cell layers in the presence of 1α,25(OH)2D3, tartrate-resistant acid phosphatase (TRAP)–positive cells first appeared within 24 h, and their number increased thereafter. OCPs also differentiated into TRAP-positive cells within 48 h on the calvarial cell layer which had been pretreated with either 1α,25(OH)2D3, PTH, or PGE2. Autoradiography using [125I]-labeled calcitonin showed that TRAP-positive cells formed on the calvarial cell layer expressed calcitonin receptors. Direct contact between OCPs and calvarial cells was required for the differentiation of OCPs into TRAP-positive cells. Flow cytometric analysis revealed that OCPs were positive for Mac-1, Mac-2, and Gr-1 but negative for F4/80, B220 and CD3e. Calvarial cells obtained from macrophage-colony stimulating factor (M-CSF)–deficient osteopetrotic (op/op) mice did not support OCP formation. A cell preparation disaggregated from long bones of newborn mice contained OCPs that differentiated into TRAP-positive cells on calvarial cells within 48 h, but cell preparations of freshly isolated bone marrow cells and alveolar macrophages did not. These results suggest that OCPs are specific cells which are formed only in the bone microenvironment and that OCPs recognize a signal(s) expressed by stromal cells in response to osteotropic factors and differentiate into osteoclasts. J. Cell. Physiol. 177:26–35, 1998. © 1998 Wiley-Liss, Inc. 相似文献
967.
Tamao Hisano Yasuo Hata Tomomi Fujii Ji-Quan Liu Tatsuo Kurihara Nobuyoshi Esaki Kenji Soda 《Proteins》1996,24(4):520-522
The dimeric L -2-haloacid dehalogenase from Pseudomonas sp. YL, (subunit mass, 26179 Da), has been crystallized by vapor diffusion, supplemented by repetitive seeding, against a 50 mM potassium dihydrogenphosphate solution (pH 4.5) containing 15% (w/v) polyethylene glycol 8,000 and 1% (v/v) n-propanol. The crystals belong to the monoclinic space group C2 with unit cell dimensions of a = 92.21 Å, b = 62.78 Angst; c = 50.84 Å, and β = 122.4°, and contain two dehalogenase dimers in the unit cell. They are of good quality and diffract up to 1.5 Å resolution. 相似文献
968.
Hiroya Ito Makoto Osaki Ikuo Uchida Tatsuo Ohya Tsutomu Sekizaki 《FEMS microbiology letters》1998,167(2):303-308
The gene encoding an outer membrane lipoprotein (OmlA) of Actinobacillus pleuropneumoniae strain WF83 (serotype 7 reference strain), designated omlA7, was sequenced. The amino acid sequence of OmlA7 showed 64.5 and 71.6% identity to that of OmlA from serotypes 1 (OmlA1) and 5 (OmlA5), respectively. The first 134 amino acids of OmlA7 were identical to those of OmlA5. A Southern blot analysis revealed the presence of a gene highly homologous to the omlA7 in the reference strains of serotypes 3, 4, 6, and 7. A Western blot analysis using a specific antiserum against a recombinant OmlA7 detected expression of the homologous proteins in the serotypes 4, 6, and 7 reference strains and a serotype 3 field strain, but not in a serotype 3 reference strain. The data demonstrate the third antigenically distinct OmlA is expressed in A. pleuropneumoniae. 相似文献
969.
970.
Yasunori Yokota Kohji Hanasaki Takashi Ono Hitoshi Nakazato Tatsuo Kobayashi Hitoshi Arita 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》1999,1438(2):213-222
Endotoxic shock is a systemic inflammatory process, involving a variety of proinflammatory mediators. Two types of secretory phospholipase A2 (sPLA2) have been implicated in this process. Group IB sPLA2 (PLA2-IB) binds to the PLA2 receptor (PLA2R), and PLA2R-deficient mice exhibit resistance to endotoxin-induced lethality with reduced plasma levels of proinflammatory cytokines, such as TNF-α. Group IIA sPLA2 (PLA2-IIA) is found in many tissues and cell types, and local and systemic levels are elevated under numerous inflammatory conditions including sepsis. In this study, we investigated the effect of a specific sPLA2 inhibitor, indoxam, on murine endotoxic shock. Indoxam suppressed the elevation of plasma TNF-α with a similar potency in PLA2-IIA-expressing and PLA2-IIA-deficient mice after LPS challenge. In PLA2-IIA-deficient mice, indoxam also suppressed the elevation of plasma IL-1β, IL-6 and NO, and prolonged survival after LPS challenge. Indoxam was found to block the PLA2-IB binding to murine PLA2R with a high potency (Ki=30 nM). The inhibitory effects of indoxam on the LPS-induced elevation of plasma TNF-α levels could not be observed in mice deficient in PLA2R. These findings suggest that indoxam blocks the production of proinflammatory cytokines during endotoxemia through PLA2-IIA-independent mechanisms, possibly via blockade of the PLA2R function. 相似文献