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41.
Preventing Staphylococcus aureus sepsis through the inhibition of its agglutination in blood 总被引:1,自引:0,他引:1
McAdow M Kim HK Dedent AC Hendrickx AP Schneewind O Missiakas DM 《PLoS pathogens》2011,7(10):e1002307
Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci--coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA)--were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans. 相似文献
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A unique family of endothelial cell polypeptide mitogens: the antigenic and receptor cross-reactivity of bovine endothelial cell growth factor, brain-derived acidic fibroblast growth factor, and eye-derived growth factor-II 总被引:9,自引:0,他引:9 下载免费PDF全文
A B Schreiber J Kenney J Kowalski K A Thomas G Gimenez-Gallego M Rios-Candelore J Di Salvo D Barritault J Courty Y Courtois 《The Journal of cell biology》1985,101(4):1623-1626
Bovine brain, hypothalamus, pituitary, and retina contain potent anionic polypeptide mitogens for endothelial cells. Immunological assays using murine monoclonal antibodies against bovine endothelial cell growth factor (ECGF) and radioreceptor assays using [125I]ECGF were performed to determine the cross-reactivity of ECGF with bovine acidic pI brain-derived fibroblast growth factor (acidic FGF) and bovine eye-derived growth factor-II [EDGF-II). We observed that acidic FGF and EDGF-II are recognized by anti-ECGF monoclonal antibodies and compete with [125I] ECGF for receptor occupancy. Furthermore, the biological activity of ECGF, acidic FGF, and EDGF-II is potentiated by the glycosaminoglycan, heparin. These results argue that ECGF, acidic FGF, and EDGF-II belong to a common family of polypeptide growth factors. 相似文献
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Robo4 maintains vessel integrity and inhibits angiogenesis by interacting with UNC5B 总被引:1,自引:0,他引:1
Koch AW Mathivet T Larrivée B Tong RK Kowalski J Pibouin-Fragner L Bouvrée K Stawicki S Nicholes K Rathore N Scales SJ Luis E del Toro R Freitas C Bréant C Michaud A Corvol P Thomas JL Wu Y Peale F Watts RJ Tessier-Lavigne M Bagri A Eichmann A 《Developmental cell》2011,20(1):33-46
Robo4 is an endothelial cell-specific member of the Roundabout axon guidance receptor family. To identify Robo4 binding partners, we performed a protein-protein interaction screen with the Robo4 extracellular domain. We find that Robo4 specifically binds to UNC5B, a vascular Netrin receptor, revealing unexpected interactions between two endothelial guidance receptors. We show that Robo4 maintains vessel integrity by activating UNC5B, which inhibits signaling downstream of vascular endothelial growth factor (VEGF). Function-blocking monoclonal antibodies against Robo4 and UNC5B increase angiogenesis and disrupt vessel integrity. Soluble Robo4 protein inhibits VEGF-induced vessel permeability and rescues barrier defects in Robo4(-/-) mice, but not in mice treated with anti-UNC5B. Thus, Robo4-UNC5B signaling maintains vascular integrity by counteracting VEGF signaling in endothelial cells, identifying a novel function of guidance receptor interactions in the vasculature. 相似文献
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Fernando ngel Fernndezlvarez Marc Farr Antoni SnchezMrquez Roger Villanueva Oscar Escolar Joan Navarro 《Ecology and evolution》2020,10(23):12685
Larval mortality is a keystone ecological factor for many benthic octopus since it mostly occurs before their settlement in the sea bottom as benthic juveniles. The literature had revealed that records of adult animals with morphological abnormalities (teratologies) are fewer in species with complex life cycle than in those with direct development. This is a direct consequence of the morphological, physiological, and development challenges that the transition from the larval to the adult morphology represents. During a routine fishing sample, we found an immature female horned octopus with additional buccal structures in two suckers of its ventral arms, likely rendering these suckers as inefficient. Based on the literature about the natural history of octopus, we provide evidence that these abnormalities were present at the moment of hatch. We evaluated the impact of the teratologies by comparing the shape of the buccal beaks and the trophic niche of the individual with five normal conspecifics. Although the beaks showed a different shape than normal individuals, the trophic niche was similar. Surprisingly, the teratological condition of the individual likely had no severe impacts on its life, even though it likely represents a handicap for its survival during its planktonic life. We also comment on other previous records from the literature of teratological adult octopus to highlight the amazing adaptive capacity of octopus to deal with challenging morphologies. 相似文献
46.
SNP frequency, haplotype structure and linkage disequilibrium in elite maize inbred lines 总被引:3,自引:0,他引:3
Ada Ching Katherine S Caldwell Mark Jung Maurine Dolan Oscar S Smith Scott Tingey Michele Morgante Antoni J Rafalski 《BMC genetics》2002,3(1):19-14
Background
Recent studies of ancestral maize populations indicate that linkage disequilibrium tends to dissipate rapidly, sometimes within 100 bp. We set out to examine the linkage disequilibrium and diversity in maize elite inbred lines, which have been subject to population bottlenecks and intense selection by breeders. Such population events are expected to increase the amount of linkage disequilibrium, but reduce diversity. The results of this study will inform the design of genetic association studies. 相似文献47.
Antoni Warzecha 《Mycopathologia》1963,20(3-4):287-296
Zusammenfassung Es wurde die Wirkung der Sorbinsäure (C6H8O2), der Propionsäure (CH3CH2COOH) und des Aktidions (Zykloheximide) auf die Entwicklung des PilzesTrichophyton gypseum var.asteroides untersucht.Von den drei angewandten chemischen Verbindungen hatte sich die Sorbinsäure als die wirksamste erwiesen; die das Pilzwachstum hemmende Dose beträgt hier 0,01 %.Die Propionsäure wirkt fungistatisch in einer Konzentration von 0,05 %.Das in den Untersuchungen angewandte Aktidion hat sich als ein das Wachstum desTrichophyton gypseum beschleunigender Faktor erwiesen. Bei einer Konzentration des Aktidions von 0,01 bis 1 % konnte beobachtet werden, dass die Entwicklung des Pilzes um so aktiver vor sich ging, je grösser die Konzentration des Aktidions war.
Summary The present investigation is dealing with the effect of the sorbic acid (C6H8O2), an unsaturated aliphatic acid, the propionic acid (CH3CH2COOH), an oxidation product of normal propyl alcohol, and the actidione (cycloheximide) on the development of the fungusTrichophyton gypseum var.asteroides.From the three chemicals used, the sorbic acid has proved itself as the most effective; the dose, which has inhibited the development of the fungus, is here 0.01 %.The propionic acid acts fungistatic in a concentration of 0.05 %.The actidione which has been used in the experiment, has proved itself as a growth factor ofTrichophyton gypseum. In the concentration of the actidione from 0.01 % to 1 % it could be observed, that the development of the fungus was the more active, the greater was the concentration of the actidione.相似文献
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