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991.
The sigma54 factor has been previously described to be involved in Listeria monocytogenes sensitivity to mesentericin Y105, a subclass IIa bacteriocin. Here, we identified the rpoN gene, encoding sigma54, of Enterococcus faecalis JH2-2 and showed that its interruption leads to E. faecalis resistance to different subclass IIa bacteriocins. Moreover, this rpoN mutant remained sensitive to nisin, a class I bacteriocin, suggesting that sigma54 is especially involved in sensitivity
to subclass IIa bacteriocins.
Received: 5 May 2000 / Accepted 28 June 2000 相似文献
992.
993.
Altieri Paula Paz Laura Estefana Ferreira Ana Clara Colpo Karine Delevati Rodrigues Captulo Alberto Jensen Roberto Costa Vladimir Ocon Carolina 《Limnology》2022,23(1):103-110
Limnology - Knowing the interactions between exotic and native species is essential to establish possible threats to the local fauna. In this study, we assessed the use of food resources and diet... 相似文献
994.
995.
Prostaglandin I2 analogs inhibit proinflammatory cytokine production and T cell stimulatory function of dendritic cells 总被引:1,自引:0,他引:1
Zhou W Hashimoto K Goleniewska K O'Neal JF Ji S Blackwell TS Fitzgerald GA Egan KM Geraci MW Peebles RS 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(2):702-710
Signaling through the PGI(2) receptor (IP) has been shown to inhibit inflammatory responses in mouse models of respiratory syncytial viral infection and OVA-induced allergic responses. However, little is known about the cell types that mediate the anti-inflammatory function of PGI(2.) In this study, we determined that PGI(2) analogs modulate dendritic cell (DC) cytokine production, maturation, and function. We report that PGI(2) analogs (iloprost, cicaprost, treprostinil) differentially modulate the response of murine bone marrow-derived DC (BMDC) to LPS in an IP-dependent manner. The PGI(2) analogs decreased BMDC production of proinflammatory cytokines (IL-12, TNF-alpha, IL-1alpha, IL-6) and chemokines (MIP-1alpha, MCP-1) and increased the production of the anti-inflammatory cytokine IL-10 by BMDCs. The modulatory effect was associated with IP-dependent up-regulation of intracellular cAMP and down-regulation of NF-kappaB activity. Iloprost and cicaprost also suppressed LPS-induced expression of CD86, CD40, and MHC class II molecules by BMDCs and inhibited the ability of BMDCs to stimulate Ag-specific CD4 T cell proliferation and production of IL-5 and IL-13. These findings suggest that PGI(2) signaling through the IP may exert anti-inflammatory effects by acting on DC. 相似文献
996.
Mouzat K Prod'homme M Volle DH Sion B Déchelotte P Gauthier K Vanacker JM Lobaccaro JM 《The Journal of biological chemistry》2007,282(7):4693-4701
The uterus is an organ where lipid distribution plays a critical role for its function. Here we show that nuclear receptor for oxysterols LXRbeta prevents accumulation of cholesteryl esters in mouse myometrium by controlling expression of genes involved in cholesterol efflux and storage (abca1 and abcg1). Upon treatment with an LXR agonist that mimics activation by oxysterols, expression of these target genes was increased in wild-type mice, whereas under basal conditions, lxralpha;beta(-/-) mice exhibited a marked decrease in abcg1 accumulation. This change resulted in a phenotype of cholesteryl ester accumulation. Besides, a defect of contractile activity induced by oxytocin or PGF2alpha was observed in mice lacking LXRbeta. These results imply that LXRbeta provides a safety valve to limit cholesteryl ester levels as a basal protective mechanism in the uterus against cholesterol accumulation and is necessary for a correct induction of contractions. 相似文献
997.
998.
Moffatt P Thomas G Sellin K Bessette MC Lafrenière F Akhouayri O St-Arnaud R Lanctôt C 《The Journal of biological chemistry》2007,282(50):36454-36462
Osteocrin (Ostn) is a recently discovered secreted protein produced by cells of the osteoblast lineage that shows a well conserved homology with members of the natriuretic peptide (NP) family. We hypothesized that Ostn could interact with the NP receptors, thereby modulating NP actions on the skeleton. Ostn binds specifically and saturably to the NP peptide receptor-C (NPR-C) receptor with a Kd of approximately 5 nM with no binding to the GC-A or GC-B receptors. Deletion of several of the residues deemed important for NP binding to NPR-C led to abolition of Ostn binding, confirming the presence of a "natriuretic motif." Functionally, Ostn was able to augment C-type natriuretic peptide-stimulated cGMP production in both pre-chondrocytic (ATDC5) and osteoblastic (UMR106) cells, suggesting increased NP levels due to attenuation of NPR-C associated NP clearance. Ostn-transgenic mice displayed elongated bones and a marked kyphosis associated with elevated bone cGMP levels, suggesting that elevated natriuretic peptide activity contributed to the increased bone length possibly through an increase in growth plate chondrocyte proliferation. Thus, we have demonstrated that Ostn is a naturally occurring ligand of the NPR-C clearance receptor and may act to locally modulate the actions of the natriuretic system in bone by blocking the clearance action of NPR-C, thus locally elevating levels of C-type natriuretic peptide. 相似文献
999.
Tiberti LA Yariwake JH Ndjoko K Hostettmann K 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,846(1-2):378-384
A comparative analysis of the flavonoid components of the leaves of two medicinal plants known in Brazil as "espinheira santa", namely, Maytenus ilicifolia Mart. ex Reiss. and M. aquifolium Mart. (Celastraceae), and a hybrid plant, M. aquifoliumxM. ilicifolia, has been carried out using high-performance liquid chromatography coupled with photodiode array UV detection and mass spectrometry. One methoxyflavonoid glycoside and 18 flavonol-3-O-glycosides were identified in the extracts on the basis of their on-line UV spectra (measured in the absence and presence of shift reagents) and multiple stage mass spectral data. Fingerprint analysis of the flavonoid extracts revealed significant differences in the profiles of the two Maytenus species, while the hybrid plant contained flavonoids found in both parent species. 相似文献
1000.
Nadia Mushtaq Roberta Schmatz Mushtaq Ahmed Luciane Belmonte Pereira Pauline da Costa Karine Paula Reichert Diéssica Dalenogare Luana Paula Pelinson Juliano Marchi Vieira Naiara Stefanello Lizielle Souza de Oliveira Nadia Mulinacci Maria Bellumori Vera Maria Morsch Maria Rosa Schetinger 《Journal of physiology and biochemistry》2015,71(4):743-751