Beta Toxin
Mostrando 13-24 de 465 artigos, teses e dissertações.
-
13. Detection of alpha, beta and epsilon toxin genes of Clostridium perfringens isolated from cattle?s clinical samples by polimerase chain reaction / Detecção dos genes das toxinas alfa, beta e épsilon de Clostridium perfringens isolados a partir de amostras clínicas de bovinos pela reação em cadeia da polimerase
Clostridium perfringens is an anaerobic micro-organism that is present in the soil and gastrointestinal tract of mammals. It causes food poisoning in humans, enterotoxemic diseases in domestic animals and gas gangrene in both. C. perfringens is classified into five types (A, B, C, D and E) according to the production of four major toxins (alpha, beta, epsilo
Publicado em: 2004
-
14. Molecular investigation of tRNA genes integrity and its relation to pathogenicity islands in Shiga toxin-producing Escherichia coli (STEC) strains
tRNA genes are known target sites for the integration of pathogenicity islands (PAI) and other genetic elements, such as bacteriophages, into bacterial genome. In most STEC (Shiga toxin-producing Escherichia coli), the PAI called LEE (locus of enterocyte effacement) is related to bacterial virulence and is mostly associated to the tRNA genes selC and pheU. I
Genetics and Molecular Biology. Publicado em: 2004
-
15. Mecanismo de transporte iônico em íleo de coelho, induzido por microcistina LR de Microcystis aeruginos: Participação de macrófagos,Il-1beta, TNFalpha e mediadores pró-inflamatórios / Mechanism of ionic transport in ileum rabbit induced by microcystin-LR of Microcystis aeruginosa: Role of macrophages, IL-1b, TNF-a and pro-inflammatory mediators
This work as main objective to evaluate the eletrogenic effect in preparations of íleum of rabbit fixes in chambers of Üssing, in presence of supernatant of macrophages (S.MfS), stimulated with microcistin-LR (MCLR), of Microcystis aeruginosa. S.MfS estimulated with MCLR (3,2.10-7M; 9,6.10-7M e 3,2.10-6M), produces effect secretion, of the form dose-depend
Publicado em: 2003
-
16. Shiga toxin-associated hemolytic uremic syndrome: interleukin-1 beta enhancement of Shiga toxin cytotoxicity toward human vascular endothelial cells in vitro.
Development of hemolytic uremic syndrome (HUS) after infection by Shigella dysenteriae 1 or enterohemorrhagic Escherichia coli has been associated with the production of Shiga toxins (verotoxins). The putative target of Shiga toxins in HUS is the renal microvascular endothelium. This report shows that preincubation of human umbilical vein endothelial cells (
-
17. Clostridium perfringens Beta-Toxin Forms Potential-Dependent, Cation-Selective Channels in Lipid Bilayers
Recombinant beta-toxin from Clostridium perfringens type C was found to increase the conductance of bilayer lipid membranes (BLMs) by inducing channel activity. The channels exhibited a distribution of conductances within the range of 10 to 380 pS, with the majority of the channels falling into two categories of conductance at 110 and 60 pS. The radii of bet
American Society for Microbiology.
-
18. Molecular genetic analysis of beta-toxin of Clostridium perfringens reveals sequence homology with alpha-toxin, gamma-toxin, and leukocidin of Staphylococcus aureus.
Oligonucleotide probes designed on the basis of the N-terminal sequence of Clostridium perfringens beta-toxin were used to isolate the encoding gene (cpb). The nucleotide sequence of cpb was determined, and on the basis of DNA hybridization experiments it was shown that the gene is found only in type B and C strains of C. perfringens. The deduced amino acid
-
19. Effect of heptakis (2,6-O-dimethyl) beta-cyclodextrin on the production of pertussis toxin by Bordetella pertussis.
The effect of heptakis (2,6-O-dimethyl) beta-cyclodextrin (Me beta CD) on the production of pertussis toxin was evaluated. The addition of Me beta CD to the medium stimulated cell growth and pertussis toxin production. Me beta CD enhanced pertussis toxin production 100 times more in synthetic media, such as Stainer-Scholte medium (D. W. Stainer and M. J. Sch
-
20. Regulation of toxinogenesis in Corynebacterium diphtheriae. I. Mutations in bacteriophage beta that alter the effects of iron on toxin production.
Diphtherial toxin is produced in maximal yields by Corynebacterium diphtheriae (C7(beta tox+) only when iron is present in growth-limiting amounts. Toxin production is markedly decreased under high-iron conditions. We studied the role of the bacteriophage beta genome in this apparent regulation of toxin production by iron. Using a passive immune hemolysis as
-
21. Purification of beta-toxin from Clostridium perfringens type C.
Beta-toxin was purified about 340-fold from culture supernatant fluid of Clostridium perfringens type C with a yield of about 24% in terms of biologically active beta-toxin. The purification involved ammonium sulfate fractionation, gel filtration through Sephadex G-100, isoelectrofocusing in a pH 3 to 6 gradient, and immunoaffinity chromatography. The purifi
-
22. Beta-Adrenergic Blocking Activity of Yersinia pestis Murine Toxin
Yersinia pestis plague murine toxin has been found to inhibit the mobilization of free fatty acids in mice in a manner similar to that of beta-adrenergic blocking agents. The blockage is detectable 75 min after injection of the toxin (1 to 2 mean lethal doses). The degree of inhibition was directly correlated with the toxicity of a given toxin preparation. A
-
23. Atypical cpb2 Genes, Encoding Beta2-Toxin in Clostridium perfringens Isolates of Nonporcine Origin
Beta2-toxin, encoded by cpb2, is implicated in the pathogenesis of Clostridium perfringens enteritis. However, cpb2 genes from nonporcine C. perfringens isolates were not always expressed, at least in vitro. Nucleotide sequencing identified atypical cpb2 genes with 70.2 to 70.7% DNA identity to previously identified (consensus) cpb2. Atypical beta2-toxin dis
American Society for Microbiology.
-
24. Selective killing of human monocytes and cytokine release provoked by sphingomyelinase (beta-toxin) of Staphylococcus aureus.
The best-known activity of Staphylococcus aureus sphingomyelinase C, alias beta-toxin, is as a hemolysin that provokes hot-cold lysis of erythrocytes which contain substantial amounts of sphingomyelin in the plasma membrane. Sheep erythrocytes are most susceptible, and we found that one hemolytic unit, representing the toxin concentration that elicits 50% he