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81.
Influenza virus infection causes severe respiratory disease such as that due to avian influenza (H5N1). Influenza A viruses proliferate in human epithelial cells, which produce inflammatory cytokines/chemokines as a "cytokine storm" attenuated with the viral nonstructural protein 1 (NS1). Cytokine/chemokine production in A549 epithelial cells infected with influenza A/H1N1 virus (PR-8) or nonstructural protein 1 (NS1) plasmid was examined in vitro. Because tumor necrosis factor-α (TNF-α) and regulated upon activation normal T-cell expressed and secreted (RANTES) are predominantly produced from cells infected with PR-8 virus, the effects of mRNA knockdown of these cytokines were investigated. Small interfering (si)TNF-α down-regulated RANTES expression and secretion of RANTES, interleukin (IL)-8, and monocyte chemotactic protein-1 (MCP-1). In addition, siRANTES suppressed interferon (IFN)-γ expression and secretion of RANTES, IL-8, and MCP-1, suggesting that TNF-α stimulates production of RANTES, IL-8, MCP-1, and IFN-γ, and RANTES also increased IL-8, MCP-1, and IFN-γ. Furthermore, administration of TNF-α promoted increased secretion of RANTES, IL-8, and MCP-1. Administration of RANTES enhanced IL-6, IL-8, and MCP-1 production without PR-8 infection. These results strongly suggest that, as an initial step, TNF-α regulates RANTES production, followed by increase of IL-6, IL-8, and MCP-1 and IFNs concentrations. At a later stage, cells transfected with viral NS1 plasmid showed production of a large amount of IL-8 and MCP-1 in the presence of the H(2)O(2)-myeloperoxidse (MPO) system, suggesting that NS1 of PR-8 may induce a "cytokine storm" from epithelial cells in the presence of an H(2)O(2)-MPO system.  相似文献   
82.
We designed and synthesized N-substituted 8-azatetrahydroquinolone derivatives as selective M1 and M4 muscarinic acetylcholine receptors agonists. Optimization of selected derivatives led to the discovery of compound 7 as a highly potent M1 and M4 agonist with weak hERG inhibition. Oral administration of compound 7 improved psychosis-like behavior in rats.  相似文献   
83.
For the competition system of phytoplankton and bacteria through inorganic phosphorus, our mathematical model showed that mutualistic relationships between them could occur due to production and consumption of extracellular organic carbon by phytoplankton and bacteria. In our model, phytoplankton are limited in their growth by light and phosphorus, and bacteria are limited in their growth by phosphorus and carbon released from phytoplankton. We adopted permanence as a criterion of the coexistence in mathematical analysis, and led necessary conditions of permanence in the model. Under these coexistence conditions, we estimated the strength of total effects of interactions between phytoplankton and bacteria at the steady state by press perturbation method. The results of this estimation indicated the mutualistic interactions between phytoplankton and bacteria. This suggests that mutualistic situation could occur due to the introduction of carbon flow from phytoplankton to bacteria, even if phytoplankton and bacteria compete with each other through common resource, inorganic phosphorus.  相似文献   
84.
While screening for bioactive compounds from edible mushrooms, a new potent antioxidant, vialinin A (1), together with a known compound, ganbajunin B (2), and a mixture of ganbajunins D (3) and E (4), were isolated from the dry fruiting bodies of Thelephora vialis. The structure of 1, 5',6'-bis(phenylacetoxy)-1,1':4',1'-terphenyl-2',3',4,4'-tetraol, was elucidated by spectroscopic and chemical methods. This compound had strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging activity with an EC(50) value of 14.0 microM, nearly equal to that of butylated hydroxytoluene (BHT; EC(50) = 10.0 microM). A radical scavenging experiment using 1 and DPPH radicals indicated that 1 donated two hydrogen atoms to two molecules of the DPPH radical under hydrophobic conditions.  相似文献   
85.
One feature of volcanic lakes influenced by subaqueous fumaroles existing at lake bottoms (called active crater lakes) is the remarkable color of their waters: turquoise or emerald green. The active crater lake named Yudamari at Mt. Nakadake of Aso volcano, Japan, takes on a milky pale blue-green. The particular blue component of the lake water color results from Rayleigh scattering of sunlight by very fine aqueous colloidal sulfur particles; the green component is attributable to absorption of sunlight by dissolved ferrous ions. An objective color observation conducted during 2000–2007 revealed that the lake water color changed from blue-green to solid green. The disappearance of the blue ingredient of the water color will result in diminution of aqueous colloidal sulfur from chemical analyses of lake waters sampled simultaneously. The aqueous sulfur is produced by the reaction of sulfur dioxide and hydrogen sulfide supplied from subaqueous fumaroles. However, its production efficiency decreases by domination of sulfur dioxide in the subaqueous fumarolic sulfur gas species with increasing subaqueous fumarolic temperature. The disappearance of blue ingredients from the blue-green color of the lake water may be attributed to activation of subaqueous fumarole activity.  相似文献   
86.
Sporophytic self-incompatibility (SSI) in the genus Ipomoea (Convolvulaceae) is controlled by a single polymorphic S locus. We have previously analyzed genomic sequences of an approximately 300 kb region spanning the S locus of the S 1 haplotype and characterized the genomic structure around this locus. Here, we further define the physical size of the S locus region by mapping recombination breakpoints, based on sequence analysis of PCR fragments amplified from the genomic DNA of recombinants. From the recombination analysis, the S locus of the S 1 haplotype was delimited to a 0.23 cM region of the linkage map, which corresponds to a maximum physical size of 212 kb. To analyze differences in genomic organization between S haplotypes, fosmid contigs spanning approximately 67 kb of the S 10 haplotype were sequenced. Comparison with the S 1 genomic sequence revealed that the S haplotype-specific divergent regions (SDRs) spanned 50.7 and 34.5 kb in the S 1 and S 10 haplotypes, respectively and that their flanking regions showed a high sequence similarity. In the sequenced region of the S 10 haplotype, five of the 12 predicted open reading frames (ORFs) were found to be located in the divergent region and showed co-linear organization of genes between the two S haplotypes. Based on the size of the SDRs, the physical size of the S locus was estimated to fall within the range 34–50 kb in Ipomoea.  相似文献   
87.
doi: 10.1111/j.1741‐2358.2011.00509.x New method for determining surface roughness of tongue Objective: The degree of atrophy of the lingual papillae in elderly individuals was evaluated using a quantitative method. Subjects and methods: One hundred and eighty‐two subjects living in nursing homes and 20 healthy adults as controls were studied. To express the degree of atrophy of the lingual papillae quantitatively, lingual surface roughness was determined by taking an impression with silicone dental material. Based on the impressions obtained from the elderly subjects, they were classified by three expert dentists into three groups: Normal, Smooth and Rough. The same determinations were also performed in the 20 healthy controls and compared with 38 of the elderly subjects who had agreement from all of the experts and without the presence of fissures (Normal, n = 6; Smooth, n = 12; Rough, n = 20). Results: The roughness average value for the controls was 65.0 μm, while that for the elderly subjects in the Normal, Smooth and Rough groups was 73.9 μm, 42.2 μm and 94.1 μm, respectively, which were significantly different. Conclusion: The present results indicate that the present technique of obtaining an impression of the tongue surface is simple and reliable for routine evaluation and quantification of the degree of atrophy as well as morphology of the lingual papillae.  相似文献   
88.
Polyamine compound deoxyspergualin (DSG) is a potent immunosuppressive agent that has been applied clinically for protecting graft rejection and treatment of Wegener's granulomatosis. Though DSG can bind to heat-shock proteins (HSPs) in cells, its mechanism of immunosuppressive action remains unknown. It is widely accepted that extracellular HSPs are capable of stimulating dendritic cells (DC) through cell surface receptors, leading to DC activation and cytokine release. In this study, we examined if DSG analogs could inhibit HSP70-induced DC activation. Bone marrow derived immature mouse DCs and peripheral blood mononuclear cell-derived immature human DCs were generated and incubated with Alexa 488-labeled Hsp70 in the presence of methoxyDSG (Gus-1) that had comparable HSP70-binding affinity to DSG or DSG analog GUS-7, which had much more reduced binding affinity for HSP70. The binding of HSP70 to immature DCs was analyzed by laser microscopy and flow cytometry. HSP70-induced DC activation was assessed by TNF-α release by enzyme-linked immunosorbent assay. Binding of Hsp70 to the cell surface of immature DCs was inhibited under the presence of Gus-1, but not under the presence of Gus-7. Immature DCs were activated and released TNF-α by the stimulation with HSP70 for 12 hours; however, the HSP70-induced TNF-α release was suppressed under the presence of Gus-1, and partially suppressed under the presence of Gus-7. Similar results were observed when immature human DCs were stimulated under the same conditions. Immunosuppressive mechanism of DSG may be explained, at least in part, by the inhibition of extracellular HSP70-DC interaction and HSP70-induced activation of immature DCs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
89.
90.
The roles of Sonic hedgehog (Shh) and Bone morphogenetic protein-2 (Bmp-2) in osteoblast differentiation were investigated using in vitro cell systems. Recombinant amino-terminal portion of SHH (rSHH-N) dose dependently stimulated ALP activity in C3H10T1/2 and MC3T3-E1 cells. rSHH-N induced expression of Osteocalcin mRNA in C3H10T1/2 cells. A soluble form of the receptor for type IA BMP receptor antagonized rSHH-N-induced ALP activity in C3H10T1/2 and MC3T3-E1 cells, indicating that BMPs are involved in SHH-induced osteoblast differentiation. Simultaneous supplement with rSHH-N and BMP-2 synergistically induced ALP activity and expression of Osteocalcin mRNA in C3H10T1/2 cells. Pretreatment with rSHH-N for 6 h enhanced the response to BMP-2 by increasing ALP activity in C3H10T1/2 and MC3T3-E1 cells. Stimulatory effects of rSHH-N and additive effects with rSHH-N and BMP-2 on ALP activity were also observed in mouse primary osteoblastic cells. Transplantation of BMP-2 (1 microg) into muscle of mice induced formation of ectopic bone, whereas transplantation of r-SHH-N (1-5 microg) failed to generate it. These results indicate that Shh plays important roles in osteoblast differentiation by cooperating with BMP.  相似文献   
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