The Experts below are selected from a list of 19278 Experts worldwide ranked by ideXlab platform
Patrick M. Schlievert - One of the best experts on this subject based on the ideXlab platform.
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α and β Chains of Hemoglobin Inhibit Production of Staphylococcus aureus Exotoxins
Biochemistry, 2007Co-Authors: Patrick M. Schlievert, Laura C. Case, Kimberly A. Nemeth, Catherine C. Davis, Yiping Sun, Wendy Qin, Fancheng Wang, Amanda J. Brosnahan, John A. Mleziva, Marnie L. PetersonAbstract:Prior studies suggest Staphylococcus aureus Exotoxins are not produced when the organism is cultured in human blood. Human blood was fractionated into plasma and water-lysed red blood cells, and it was demonstrated that mixtures of α and β globins of hemoglobin (as low as 1 μg/mL) inhibited S. aureus Exotoxin production while increasing production of protein A and not affecting bacterial growth. Pepsin but not trypsin digestion destroyed the ability of α and β globin to inhibit Exotoxin production. Exotoxin production by both methicillin-resistant and methicillin-susceptible organisms was inhibited. Production of streptococcal pyrogenic Exotoxin A by Streptococcus pyogenes was unaffected by α and β globin chains but was inhibited when produced in S. aureus. Use of isogenic S. aureus strains suggested the targets of α and β globin chains, leading to inhibition of staphylococcal Exotoxins, included the two-component system SrrA−SrrB. δ hemolysin production was also inhibited, suggesting the two-component (a...
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Stability of streptococcal pyrogenic Exotoxin production with laboratory manipulation of group A streptococci
The Journal of infectious diseases, 1991Co-Authors: Edward L. Kaplan, Dwight R. Johnson, Anthony Wlazlo, Michael H. Kim, Patrick M. SchlievertAbstract:Because of reported differences in the production of streptococcal pyrogenic Exotoxins by group A strains associated with severe streptococcal infections, the stability of Exotoxin production by specific strains was examined by passing group A streptococci on blood agar culture plates daily for 20 days. No changes were detected in either Exotoxin genes or in Exotoxin production during this time, suggesting that these reported differences are due to other explanations such as differences in the strains collected from various geographic areas or to laboratory methodologic differences.
A Akasawa - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the staphylococcal Exotoxins and their specific IgE in childhood atopic dermatitis.
The Journal of allergy and clinical immunology, 1999Co-Authors: I Nomura, K Tanaka, H Tomita, T Katsunuma, Y Ohya, N Ikeda, T Takeda, H Saito, A AkasawaAbstract:Superantigenic Exotoxins produced by Staphylococcus aureus and their specific IgE antibodies are thought to be important precipitating factors of atopic dermatitis (AD), but there are few reports evaluating these 2 factors at the same time. We examined whether the presence of the Exotoxins sampled from the skin of patients with AD and the levels of anti-Exotoxin IgE antibodies in their sera correlated with their severity of AD. Patients with mild-to-severe AD, 1 to 22 years of age, were evaluated by using Leicester's scoring system. Specific IgE antibodies against these Exotoxins were determined by using ELISA. S aureus was isolated from 3 different areas of the skin. We examined whether the Exotoxin (staphylococcal enterotoxin [SE]A, SEB, SEC, SED, and toxic shock syndrome toxin-1) could be detected. The levels of SEB-specific IgE were correlated with the severity of AD. Five of 6 patients having very high SEB-specific IgE antibody titers were under 6 years of age, and SEB was most frequently isolated (41%). There was no difference in severity between patients with or without Exotoxin-producing S aureus. The severity of 9 patients who had both Exotoxin-producing S aureus on the skin and specific IgE antibody against the same Exotoxin in sera was significantly higher than that of the other patients. Anti-SEB IgE titers correlate well with the severity of AD. The presence of Exotoxin-producing S aureus may precipitate AD through its specific IgE antibody.
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Evaluation of the staphylococcal Exotoxins and their specific IgE in childhood atopic dermatitis
Journal of Allergy and Clinical Immunology, 1999Co-Authors: I Nomura, K Tanaka, H Tomita, T Katsunuma, Y Ohya, N Ikeda, T Takeda, H Saito, A AkasawaAbstract:Abstract Background: Superantigenic Exotoxins produced by Staphylococcus aureus and their specific IgE antibodies are thought to be important precipitating factors of atopic dermatitis (AD), but there are few reports evaluating these 2 factors at the same time. Objective: We examined whether the presence of the Exotoxins sampled from the skin of patients with AD and the levels of anti-Exotoxin IgE antibodies in their sera correlated with their severity of AD. Methods: Patients with mild-to-severe AD, 1 to 22 years of age, were evaluated by using Leicester's scoring system. Specific IgE antibodies against these Exotoxins were determined by using ELISA. S aureus was isolated from 3 different areas of the skin. We examined whether the Exotoxin (staphylococcal enterotoxin [SE]A, SEB, SEC, SED, and toxic shock syndrome toxin-1) could be detected. Results: The levels of SEB-specific IgE were correlated with the severity of AD. Five of 6 patients having very high SEB-specific IgE antibody titers were under 6 years of age, and SEB was most frequently isolated (41%). There was no difference in severity between patients with or without Exotoxin-producing S aureus. The severity of 9 patients who had both Exotoxin-producing S aureus on the skin and specific IgE antibody against the same Exotoxin in sera was significantly higher than that of the other patients. Conclusions: Anti-SEB IgE titers correlate well with the severity of AD. The presence of Exotoxin-producing S aureus may precipitate AD through its specific IgE antibody. (J Allergy Clin Immunol 1999;104:441-6.)
I Nomura - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the staphylococcal Exotoxins and their specific IgE in childhood atopic dermatitis.
The Journal of allergy and clinical immunology, 1999Co-Authors: I Nomura, K Tanaka, H Tomita, T Katsunuma, Y Ohya, N Ikeda, T Takeda, H Saito, A AkasawaAbstract:Superantigenic Exotoxins produced by Staphylococcus aureus and their specific IgE antibodies are thought to be important precipitating factors of atopic dermatitis (AD), but there are few reports evaluating these 2 factors at the same time. We examined whether the presence of the Exotoxins sampled from the skin of patients with AD and the levels of anti-Exotoxin IgE antibodies in their sera correlated with their severity of AD. Patients with mild-to-severe AD, 1 to 22 years of age, were evaluated by using Leicester's scoring system. Specific IgE antibodies against these Exotoxins were determined by using ELISA. S aureus was isolated from 3 different areas of the skin. We examined whether the Exotoxin (staphylococcal enterotoxin [SE]A, SEB, SEC, SED, and toxic shock syndrome toxin-1) could be detected. The levels of SEB-specific IgE were correlated with the severity of AD. Five of 6 patients having very high SEB-specific IgE antibody titers were under 6 years of age, and SEB was most frequently isolated (41%). There was no difference in severity between patients with or without Exotoxin-producing S aureus. The severity of 9 patients who had both Exotoxin-producing S aureus on the skin and specific IgE antibody against the same Exotoxin in sera was significantly higher than that of the other patients. Anti-SEB IgE titers correlate well with the severity of AD. The presence of Exotoxin-producing S aureus may precipitate AD through its specific IgE antibody.
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Evaluation of the staphylococcal Exotoxins and their specific IgE in childhood atopic dermatitis
Journal of Allergy and Clinical Immunology, 1999Co-Authors: I Nomura, K Tanaka, H Tomita, T Katsunuma, Y Ohya, N Ikeda, T Takeda, H Saito, A AkasawaAbstract:Abstract Background: Superantigenic Exotoxins produced by Staphylococcus aureus and their specific IgE antibodies are thought to be important precipitating factors of atopic dermatitis (AD), but there are few reports evaluating these 2 factors at the same time. Objective: We examined whether the presence of the Exotoxins sampled from the skin of patients with AD and the levels of anti-Exotoxin IgE antibodies in their sera correlated with their severity of AD. Methods: Patients with mild-to-severe AD, 1 to 22 years of age, were evaluated by using Leicester's scoring system. Specific IgE antibodies against these Exotoxins were determined by using ELISA. S aureus was isolated from 3 different areas of the skin. We examined whether the Exotoxin (staphylococcal enterotoxin [SE]A, SEB, SEC, SED, and toxic shock syndrome toxin-1) could be detected. Results: The levels of SEB-specific IgE were correlated with the severity of AD. Five of 6 patients having very high SEB-specific IgE antibody titers were under 6 years of age, and SEB was most frequently isolated (41%). There was no difference in severity between patients with or without Exotoxin-producing S aureus. The severity of 9 patients who had both Exotoxin-producing S aureus on the skin and specific IgE antibody against the same Exotoxin in sera was significantly higher than that of the other patients. Conclusions: Anti-SEB IgE titers correlate well with the severity of AD. The presence of Exotoxin-producing S aureus may precipitate AD through its specific IgE antibody. (J Allergy Clin Immunol 1999;104:441-6.)
Noor Embi - One of the best experts on this subject based on the ideXlab platform.
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Antibody to Pseudomonas pseudomallei Exotoxin in sheep exposed to natural infection
Veterinary microbiology, 1991Co-Authors: Ghazally Ismail, Rahmah Mohamed, S. Rohana, H.s.m. Sharifah, Noor EmbiAbstract:Specific antibody to Pseudomonas pseudomallei Exotoxin was detected in sheep sera exposed to natural infection. An enzyme-linked immunosorbent assay (ELISA) was used. Serum antitoxin was present in 49.3% of sera obtained from a flock of sheep naturally exposed to P. pseudomallei infection. Among these sera, 17.0% gave titers of 10,000. In contrast, serum antitoxin was present in only 6.0% of sera collected from sheep kept on a melioidosis-free farm. The ELISA reactivity of all positive sera could be completely absorbed with purified P. pseudomallei Exotoxin. Similarly, preincubation of the Exotoxin-coated wells with specific antiserum inhibited the ELISA reactivity of sheep sera. The results indicate that Exotoxin is produced in vivo during infection by P. pseudomallei.
Woei Jer Chuang - One of the best experts on this subject based on the ideXlab platform.
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Streptococcal pyrogenic Exotoxin B antibodies in a mouse model of glomerulonephritis
Kidney International, 2007Co-Authors: Kuen-jeng Huang, Jiunn Jong Wu, Woei Jer ChuangAbstract:Streptococcal pyrogenic Exotoxin B is an extracellular cysteine protease. Only nephritis-associated strains of group A streptococci secrete this protease and this may be involved in the pathogenesis of post-streptococcal glomerulonephritis. Mice were actively immunized with a recombinant protease inactive Exotoxin B mutant or passively immunized with Exotoxin B antibody. Characteristics of glomerulonephritis were measured using histology, immunoglobulin deposition, complement activation, cell infiltration, and proteinuria. None of the mice given bovine serum albumin or Exotoxin A as controls showed any marked changes. Immunoglobulin deposition, complement activation, and leukocyte infiltration occurred only in the glomeruli of Exotoxin B-hyperimmunized mice. One particular anti-Exotoxin B monoclonal antibody, 10G, was cross-reactive with kidney endothelial cells and it caused kidney injury and proteinuria when infused into mice. This cross-reactivity may be involved in the pathogenesis of glomerulonephritis following group A streptococcal infection.
