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Syndrome Toxin (syndrome + toxin)
Selected AbstractsVirulence genes of bovine Staphylococcus aureus from persistent and nonpersistent intramammary infections with different clinical characteristicsJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2007M. Haveri Abstract Aims:, To screen putative virulence genes in Staphylococcus aureus causing persistent and nonpersistent bovine intramammary infections (IMI) with different clinical characteristics. To examine, whether a possible relationship exists between genetic profile and infection persistence, clinical signs of infection, clonal type determined by pulsed-field gel electrophoresis (PFGE), and antimicrobial resistance. Methods and Results:, One-hundred and sixty-one S. aureus isolates derived from bovine IMI, consisting of 17 different PFGE types, were screened by conventional and multiplex-polymerase chain reaction (PCR) for 24 virulence genes for haemolysins (hla-hlg), leukocidins (lukED, lukM), exfoliative toxins (eta, etb), enterotoxins (sea-seo, seu), toxic-shock syndrome toxin (tst), and genes encoding penicillin (blaZ) and methicillin resistance (mecA). The majority of S. aureus isolated at the onset of mastitis carried haemolysin genes (76·7,97·4%), lukED (96·6%), and at least one gene for pyrogenic toxin superantigen (PTSAg) (69·0%). Strains carrying PTSAg-encoding genes were more common among predominant PFGE types and in persistent IMI. Strains concomitantly possessing sed, sej, and blaZ, putatively plasmid-encoded, were typically found in connection with persistent IMI. Conclusions:, Our results suggest that certain genetic elements are over-representative in S. aureus isolates especially from persistent bovine mastitis. This phenomenon seems to be in connection with clonal type and is often concomitant with penicillin resistance. Significance and Impact of the Study:, This is the first study to investigate associations between a large number of bacterial factors and outcome of S. aureus mastitis. The finding that widespread clonal types of S. aureus causing bovine mastitis of low treatment response may harbour characteristic genes could be improved for strain-specific diagnostic purposes. [source] Superantigens from Staphylococcus aureus induce procoagulant activity and monocyte tissue factor expression in whole blood and mononuclear cells via IL-1,JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2003E. Mattsson Summary.,Background:,Staphylococcus aureus is one of the most common bacteria in human sepsis, a condition in which the activation of blood coagulation plays a critical pathophysiological role. During severe sepsis and septic shock microthrombi and multiorgan dysfunction are observed as a result of bacterial interference with the host defense and coagulation systems. Objectives:,In the present study, staphylococcal superantigens were tested for their ability to induce procoagulant activity and tissue factor (TF) expression in human whole blood and in peripheral blood mononuclear cells. Methods and results:,Determination of clotting time showed that enterotoxin A, B and toxic shock syndrome toxin 1 from S. aureus induce procoagulant activity in whole blood and in mononuclear cells. The procoagulant activity was dependent on the expression of TF in monocytes since antibodies to TF inhibited the effect of the toxins and TF was detected on the surface of monocytes by flow cytometry. In the supernatants from staphylococcal toxin-stimulated mononuclear cells, interleukin (IL)-1, was detected by ELISA. Furthermore, the increased procoagulant activity and TF expression in monocytes induced by the staphylococcal toxins were inhibited in the presence of IL-1 receptor antagonist, a natural inhibitor of IL-1,. Conclusions:,The present study shows that superantigens from S. aureus activate the extrinsic coagulation pathway by inducing expression of TF in monocytes, and that the expression is mainly triggered by superantigen-induced IL-1, release. [source] Crystallization of community-acquired respiratory distress syndrome toxin from Mycoplasma pneumoniaeACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 3 2010Olga N. Pakhomova Community-acquired respiratory distress syndrome toxin (CARDS TX) is a 591-amino-acid protein with ADP-ribosyltransferase and vacuolating activities that damages the cells lining the respiratory tracts of patients infected with the bacterial pathogen Mycoplasma pneumoniae. Crystals of CARDS TX were grown in space group C2, with unit-cell parameters a = 191.4, b = 107.4, c = 222.1,Å, , = 90.6°. A complete 2.2,Å data set was obtained from a single CARDS TX crystal. [source] Necrotizing haemorrhagic pneumonia proves fatal in an immunocompetent child due to Panton,Valentine Leucocidin, toxic shock syndrome toxins 1 and 2 and enterotoxin C-producing Staphylococcus aureusACTA PAEDIATRICA, Issue 7 2008Farah Mushtaq Abstract Panton,Valentine leucocidin (PVL) toxin-producing strains of Staphylococcus aureus (S. aureus) are associated with skin abscesses and furunculosis, with necrotizing pneumonia being a relatively rare problem. Here, we describe a fatal case of necrotizing pneumonia in a 14-year-old child who presented initially with sore throat and pyrexia. He deteriorated rapidly, developing hypotension, multiple organ failure and purpura fulminans. S. aureus was isolated from the tracheal aspirate, which was found to be positive for PVL, toxic shock syndrome toxins (TSST) 1 and 2 and staphylococcal enterotoxin C (SEC). It was postulated that purpura fulminans and toxic shock syndrome were a result of the abovementioned exotoxins. Conclusion: This case highlights the emergence of PVL-positive community-acquired S. aureus infection and association of purpura fulminans with superantigens. Practitioners should be aware of this illness in order to initiate appropriate treatment. [source] | ||||||||||