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Yano Tomomasa - One of the best experts on this subject based on the ideXlab platform.

  • Caracterização genotípica dos fatores de virulência em amostras de Escherichia coli isoladas de pacientes com cistite
    Instituto de Medicina Tropical, 2015
    Co-Authors: Tiba, Monique Ribeiro, Yano Tomomasa, Leite, Domingos Da Silva
    Abstract:

    Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (α-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (Aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.Adesinas (Fímbria P, fímbria S, fímbria do tipo 1 e a adesina afimbrial), toxinas (α-hemolisina e o fator necrosante citotóxico do tipo 1), sistemas de captação de ferro (Aerobactina), e mecanismos de defesa do hospedeiro (cápsula ou lipopolissacarídeo) são prevalentes em amostras de Escherichia coli associadas a infecções do trato urinário. O objetivo deste trabalho foi caracterizar genotipicamente 162 amostras de Escherichia coli uropatogênica (UPEC) de pacientes com cistite através do ensaio da reação em cadeia da polimerase. Foram realizados três ensaios de PCR multiplex para os seguintes fatores de virulência: papC, papE/F, alelos de papG, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, e kpsMTII. Os resultados da PCR identificaram, 158 amostras fimH (97,5%), 86 amostras kpsMTII (53,1%), 53 amostras papC/papEF/papG (32,7%), 45 amostras sfa (27,8%), 42 amostras iucD (25,9%), 41 amostras hly (25,3%), 36 amostras usp (22,2%), 30 amostras cnf-1 (18,5%) e 10 amostras afa (6,2%). Nenhuma amostra foi positiva para o gene cdtB. Neste trabalho, demonstramos que podemos encontrar múltiplas adesinas em uma única amostra e que diferentes genes de fatores de virulência podem ser encontrados em associação

  • Caracterização genotípica dos fatores de virulência em amostras de Escherichia coli isoladas de pacientes com cistite
    'FapUNIFESP (SciELO)', 2015
    Co-Authors: Tiba, Monique Ribeiro, Yano Tomomasa, Leite, Domingos Da Silva
    Abstract:

    Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (α-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (Aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.Adesinas (Fímbria P, fímbria S, fímbria do tipo 1 e a adesina afimbrial), toxinas (α-hemolisina e o fator necrosante citotóxico do tipo 1), sistemas de captação de ferro (Aerobactina), e mecanismos de defesa do hospedeiro (cápsula ou lipopolissacarídeo) são prevalentes em amostras de Escherichia coli associadas a infecções do trato urinário. O objetivo deste trabalho foi caracterizar genotipicamente 162 amostras de Escherichia coli uropatogênica (UPEC) de pacientes com cistite através do ensaio da reação em cadeia da polimerase. Foram realizados três ensaios de PCR multiplex para os seguintes fatores de virulência: papC, papE/F, alelos de papG, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, e kpsMTII. Os resultados da PCR identificaram, 158 amostras fimH (97,5%), 86 amostras kpsMTII (53,1%), 53 amostras papC/papEF/papG (32,7%), 45 amostras sfa (27,8%), 42 amostras iucD (25,9%), 41 amostras hly (25,3%), 36 amostras usp (22,2%), 30 amostras cnf-1 (18,5%) e 10 amostras afa (6,2%). Nenhuma amostra foi positiva para o gene cdtB. Neste trabalho, demonstramos que podemos encontrar múltiplas adesinas em uma única amostra e que diferentes genes de fatores de virulência podem ser encontrados em associação.255260Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

  • Características associadas à virulência de Enterococcus faecalis isolados de casos clínicos
    'FapUNIFESP (SciELO)', 2015
    Co-Authors: Furumura, Márcia T., Figueiredo, Patricia M.s., Carbonell Gleize, Darini, Ana Lucia Da Costa, Yano Tomomasa
    Abstract:

    Thirty-two clinical isolates of Enterococcus faecalis were screened for virulence factors. Twenty-four (75%) isolates produced hemolysin on Mueller-Hinton blood agar plates with sheep erythrocytes. However, the cell free heat-stable hemolysin was detected in all isolates (100%) of E. faecalis when grown in BHI-GA (BHI medium supplemented with 1% glucose and 0.03% L-arginine), but not in BHI broth alone. Twenty-four isolates (75%) produced caseinase and 23 (71.9%) lipase, but none of the isolates produced gelatinase. Fifteen (46.9%) culture filtrates caused rounding and membrane alterations with blebbing formation followed by death in HeLa and HEp-2 cells, but not in Vero cells. Thirteen isolates (40.6%) agglutinated rabbit erythrocytes, but did not produce hemagglutination in other bloods, containing or not 1% D-manose. Sixteen (50%) E. faecalis isolates adhered to HeLa cells and thirteen (40.6%) to HEp-2 cells, but all isolates adhered to polypropylene microtiter plates, indicating that clinical E. faecalis possess the ability to form biofilm in vitro. All the isolates were resistant to the bactericidal action of normal serum and did not produce Aerobactin. These findings suggest that adherence and consequently biofilm formation on ephitelial host cells are the first steps in the E. faecalis virulence and that hemolysin, lipase, caseinase and other virulence factors act as causative of human epithelial cell damages.Foram estudados os fatores de virulência de trinta e duas amostras de Enterococcus faecalis, isolados de casos clínicos. Vinte e quatro amostras (75%) produziram hemolisina em ágar sangue preparado com hemácias de carneiro. No sobrenadante da cultura em BHI nenhuma amostra produziu hemolisina, no entanto quando cultivadas em meio BHI suplementado com 1% de glucose e 0,03% de L-arginina (BHI-GA), 100% das amostras lisaram hemácias de carneiro. Vinte e quatro (75%) amostras produziram caseinase e 23 (71,9%) lipase, mas nenhuma amostra produziu gelatinase. Dezesseis (46,9%) causaram arredondamento e alteração na membrana das células, com formação de vesículas e, em seguida, a morte das células HeLa e HEp-2. Treze amostras (40,6) aglutinaram eritrócitos de coelhos, mas não aglutinaram outros eritrócitos na presença ou na ausência de 1% de D-manose. Dezesseis (50%) aderiram em células HeLa e 13 (40,6%) em células HEp-2, mas todas as amostras de E. faecalis aderiram na microplaca de polipropileno, indicando que E. faecalis isolados de casos clínicos possuem capacidade de formar biofilme in vitro. Todos os isolados mostraram-se resistentes à ação bactericida do soro normal e não produziram Aerobactina. Esses resultados sugerem que, inicialmente, a colonização ou infecção por E. faecalis ocorre pela aderência e formação de biofilme nas células epiteliais e a produção de hemolisina, lípase e caseinase pode atuar como fatores de virulência na infecção por E. faecalis.230236Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

  • Características associadas à virulência de Enterococcus faecalis isolados de casos clínicos
    Sociedade Brasileira de Microbiologia, 2015
    Co-Authors: Furumura, Márcia T., Figueiredo, Patricia M.s., Carbonell Gleize, Darini, Ana Lucia Da Costa, Yano Tomomasa
    Abstract:

    Thirty-two clinical isolates of Enterococcus faecalis were screened for virulence factors. Twenty-four (75%) isolates produced hemolysin on Mueller-Hinton blood agar plates with sheep erythrocytes. However, the cell free heat-stable hemolysin was detected in all isolates (100%) of E. faecalis when grown in BHI-GA (BHI medium supplemented with 1% glucose and 0.03% L-arginine), but not in BHI broth alone. Twenty-four isolates (75%) produced caseinase and 23 (71.9%) lipase, but none of the isolates produced gelatinase. Fifteen (46.9%) culture filtrates caused rounding and membrane alterations with blebbing formation followed by death in HeLa and HEp-2 cells, but not in Vero cells. Thirteen isolates (40.6%) agglutinated rabbit erythrocytes, but did not produce hemagglutination in other bloods, containing or not 1% D-manose. Sixteen (50%) E. faecalis isolates adhered to HeLa cells and thirteen (40.6%) to HEp-2 cells, but all isolates adhered to polypropylene microtiter plates, indicating that clinical E. faecalis possess the ability to form biofilm in vitro. All the isolates were resistant to the bactericidal action of normal serum and did not produce Aerobactin. These findings suggest that adherence and consequently biofilm formation on ephitelial host cells are the first steps in the E. faecalis virulence and that hemolysin, lipase, caseinase and other virulence factors act as causative of human epithelial cell damages.Foram estudados os fatores de virulência de trinta e duas amostras de Enterococcus faecalis, isolados de casos clínicos. Vinte e quatro amostras (75%) produziram hemolisina em ágar sangue preparado com hemácias de carneiro. No sobrenadante da cultura em BHI nenhuma amostra produziu hemolisina, no entanto quando cultivadas em meio BHI suplementado com 1% de glucose e 0,03% de L-arginina (BHI-GA), 100% das amostras lisaram hemácias de carneiro. Vinte e quatro (75%) amostras produziram caseinase e 23 (71,9%) lipase, mas nenhuma amostra produziu gelatinase. Dezesseis (46,9%) causaram arredondamento e alteração na membrana das células, com formação de vesículas e, em seguida, a morte das células HeLa e HEp-2. Treze amostras (40,6) aglutinaram eritrócitos de coelhos, mas não aglutinaram outros eritrócitos na presença ou na ausência de 1% de D-manose. Dezesseis (50%) aderiram em células HeLa e 13 (40,6%) em células HEp-2, mas todas as amostras de E. faecalis aderiram na microplaca de polipropileno, indicando que E. faecalis isolados de casos clínicos possuem capacidade de formar biofilme in vitro. Todos os isolados mostraram-se resistentes à ação bactericida do soro normal e não produziram Aerobactina. Esses resultados sugerem que, inicialmente, a colonização ou infecção por E. faecalis ocorre pela aderência e formação de biofilme nas células epiteliais e a produção de hemolisina, lípase e caseinase pode atuar como fatores de virulência na infecção por E. faecalis

Jun Guo - One of the best experts on this subject based on the ideXlab platform.

  • hypervirulent klebsiella pneumoniae hypermucoviscous and Aerobactin positive infection over 6 years in the elderly in china antimicrobial resistance patterns molecular epidemiology and risk factor
    Annals of Clinical Microbiology and Antimicrobials, 2019
    Co-Authors: Chao Liu, Jun Guo
    Abstract:

    Background The definition of hypervirulent Klebsiella pneumoniae (hvKp), traditionally regarded as hypermucoviscosity, is controversial. However, data based on both phenotype (hypermucoviscous) and genetic (Aerobactin) criteria are limited.

  • hypervirulent klebsiella pneumoniae hypermucoviscous and Aerobactin positive infection over 6 years in the elderly in china antimicrobial resistance patterns molecular epidemiology and risk factor
    Annals of Clinical Microbiology and Antimicrobials, 2019
    Co-Authors: Chao Liu, Jun Guo
    Abstract:

    The definition of hypervirulent Klebsiella pneumoniae (hvKp), traditionally regarded as hypermucoviscosity, is controversial. However, data based on both phenotype (hypermucoviscous) and genetic (Aerobactin) criteria are limited. A retrospective study was conducted in 175 geriatric patients between January 2008 and January 2014. The clinical and molecular data, including antimicrobial susceptibility testing, extended-spectrum-β-lactamase (ESBL) production, virulence gene, and multilocus sequence typing of the hvKp-group (hypermucoviscosity and Aerobactin positive) were compared with those of classic K. pneumoniae (cKp) isolates. Of 175 Kp isolates, 45.7% were hvKp. In pathogenicity, K1, K2, magA, rmpA, and rmpA2 genes were strongly associated with hvKp (P < 0.01). In the hvKp group, invasive infections (P < 0.000), liver abscess (P = 0.008), abdominal infection (P = 0.002) and septic shock (P = 0.035) are significantly higher than cKp group. Patients with better nutritional status were frequently infected with hvKp. However, host inflammatory reaction is most severe in hvKp group. Patients with diabetes (odds ratio [OR] = 2.548) and digestive diseases (OR = 2.196) are more likely to be infected with hvKp. Importantly, the detection of hvKp isolates increased from January 2008 to January 2010, January 2010 to January 2012, and January 2010 to January 2014 (12, 30, and 48 isolates, respectively). Overall, 16.3% of hvKp isolates produced ESBLs and 20.0% were MDR-hvKp. Multivariate analysis implied that infection occurred in the ICU (OR = 5.826) and patients with indwelling stomach tubes (OR = 6.461) are independent risk factors for ESBL-hvKp infection. HvKp, especially ESBL-hvKp and MDR-hvKp, is emerging in the elderly. It is essential to enhance clinical awareness and management of hvKp infections.

  • Hypervirulent Klebsiella pneumoniae (hypermucoviscous and Aerobactin positive) infection over 6 years in the elderly in China: antimicrobial resistance patterns, molecular epidemiology and risk factor
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Chao Liu, Jun Guo
    Abstract:

    Abstract Background The definition of hypervirulent Klebsiella pneumoniae (hvKp), traditionally regarded as hypermucoviscosity, is controversial. However, data based on both phenotype (hypermucoviscous) and genetic (Aerobactin) criteria are limited. Methods A retrospective study was conducted in 175 geriatric patients between January 2008 and January 2014. The clinical and molecular data, including antimicrobial susceptibility testing, extended-spectrum-β-lactamase (ESBL) production, virulence gene, and multilocus sequence typing of the hvKp-group (hypermucoviscosity and Aerobactin positive) were compared with those of classic K. pneumoniae (cKp) isolates. Results Of 175 Kp isolates, 45.7% were hvKp. In pathogenicity, K1, K2, magA, rmpA, and rmpA2 genes were strongly associated with hvKp (P 

  • characteristics of ventilator associated pneumonia due to hypervirulent klebsiella pneumoniae genotype in genetic background for the elderly in two tertiary hospitals in china
    Antimicrobial Resistance and Infection Control, 2018
    Co-Authors: Chao Liu, Jun Guo
    Abstract:

    Aerobactin is a critical factor for the hypervirulent Klebsiella pneumoniae (hvKp), but data for the Aerobactin-positive genotype of hvKp in elderly persons with ventilator-associated pneumonia (VAP) is limited. The purpose of this study is to understand the risk factors and characteristics of the hvKp genotype for elderly patients with VAP. A retrospective study of 73 elderly patients with Kp was conducted from November 2008 to December 2017 in two tertiary hospitals. The clinical and microbiological data, including inflammatory reaction, nutritional status, antimicrobial susceptibility testing, string test, extended-spectrum-β-lactamase (ESBL) production, virulence-associated gene (capsular serotype-specific gene and rmpA/A2,magA,aerobaction) and multilocus sequence typing, of the hvKp group defined as Aerobactin positive were compared with those of classic Kp strains. Of 73 Kp isolates, 46.6% were hvKp. ST23 is highly prevalent in two hospitals but is not highly associated with hvKp in different hospitals. Additionally, ST23, ST37 and ST2906 are more likely to induce lethal VAP. Most hvKp strains are sensitive to common antibiotics, but the number of multidrug-resistant (MDR) hvKp is increasing. Importantly, 38.2% of hvKp isolates produced ESBLs. Hypermucoviscosity and virulence-associated genes (K1,magA and rmpA/A2) were highly clustered in the hvKp group (P < 0.001). Cancer (P = 0.004), digestive disease (P = 0.038) and surgery (P = 0.023) within 1 month are strongly associated with the VAP-hvKp group. The incidence of septic shock (P = 0.016) and Sequential Organ Failure Assessment (SOFA) scores (P < 0.001) are significantly higher in the hvKp group. Multivariate analysis indicated that cancer (odds ratio [OR] = 5.365) is an independent risk factor for VAP-hvKp infection. The morbidity for elderly patients with VAP due to hvKp is high. MDR-HvKp is emerging, which is a great challenge for clinical practice.

  • high prevalence of hypervirulent klebsiella pneumoniae infection in the genetic background of elderly patients in two teaching hospitals in china
    Infection and Drug Resistance, 2018
    Co-Authors: Chao Liu, Jiaojiao Shi, Jun Guo
    Abstract:

    Purpose Aerobactin is a critical factor for hypervirulent Klebsiella pneumoniae (hvKp) in genetic backgrounds, but data based on the genotype for the elderly is limited. Materials and methods A retrospective study was conducted on elderly patients from June 2008 to July 2017 in 2 teaching hospitals. The clinical and microbiological data, including antimicrobial susceptibility testing, string test, extended-spectrum β-lactamase (ESBL) production, virulence gene, and multilocus sequence typing, of the hvKp group defined as Aerobactin positive were compared with those of classic K. pneumoniae isolates. Results A total of 45.7% of 202 K. pneumoniae isolates were hvKp.ST23, which were predominant in 2 hospitals, but they were not highly associated with hvKp in different hospitals. Hypermucoviscosity, K1, K2, magA, and rmpA/A2 genes were highly related to hvKp (P=0.000). With regard to the host, invasive infections (P=0.000), liver abscess (P=0.000), abdominal infection (P=0.000), pneumonia (P=0.037), and septic shock (P=0.045) were significantly higher in the elderly with hvKp. In the hvKp group, patients with better nutritional status were associated with a more severe sequential organ failure assessment score and a more serious inflammation reaction. Patients with diabetes (odds ratio [OR]=2.566) are more likely to be infected with hvKp. Previous hvKp is associated with hypermucoviscosity (OR=15.249) are often paralleled with hvKp. Importantly, 26% of hvKp isolates produced ESBLs, and most of them showed a carbapenems-resistant (CR) phenotype. Multivariate analysis implied that patients with a history of surgery within the last 1 month (OR=15.999) is an independent risk factor for CR-hvKp infection. Conclusion The prevalence of hvKP is high in the elderly. ESBL-hvKp, especially CR-hvKp, is emerging, which is a sign that clinical awareness and infection monitoring needs to improve.

Ferreira, Antônio J.p - One of the best experts on this subject based on the ideXlab platform.

  • Sorogrupos e genes de virulência em Escherichia coli isoladas de psitacídeos
    Colégio Brasileiro de Patologia Animal - CBPA, 2015
    Co-Authors: Knöbl Terezinha, Saidenberg, André B.s, Moreno, Andrea M, Gomes, Tânia A.t, Vieira, Mônica A.m, Leite, Domingos S, Blanco, Jesus E, Ferreira, Antônio J.p
    Abstract:

    Escherichia coli isolates from 24 sick psittacine birds were serogrouped and investigated for the presence of genes encoding the following virulence factors: attaching and effacing (eae), enteropathogenic E. coli EAF plasmid (EAF), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afa), capsule K1 (neu), curli (crl, csgA), temperature-sensitive hemagglutinin (tsh), enteroaggregative heat-stable enterotoxin-1 (astA), heat-stable enterotoxin -1 heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga-like toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf1), haemolysin (hly), Aerobactin production (iuc) and serum resistance (iss). The results showed that the isolates belonged to 12 serogroups: O7; O15; O21; O23; O54; O64; O76; O84; O88; O128; O152 and O166. The virulence genes found were: crl in all isolates, pap in 10 isolates, iss in seven isolates, csgA in five isolates, iuc and tsh in three isolates and eae in two isolates. The combination of virulence genes revealed 11 different genotypic patterns. All strains were negative for genes encoding for EAF, EAEC, K1, sfa, afa, hly, cnf, LT, STa, STb, stx1 and stx2. Our findings showed that some E. coli isolated from psittacine birds present the same virulence factors as avian pathogenic E. coli (APEC), uropathogenic E. coli (UPEC) and Enteropathogenic E. coli (EPEC) pathotypes.Amostras de Escherichia coli isoladas de 24 psitacídeos doentes foram sorogrupadas e investigadas para a presença de genes que codificam os seguintes fatores de virulência: attaching e effacing (eae), plasmídeo EAF (EAF), pili associado à pielonefrite (pap), fímbria S (sfa), adesina afimbrial (afa), cápsula K1 (neu), curli (crl, csgA), hemaglutinina termosensível (tsh), enterotoxina termo-estável 1 de E. coli enteroagregativa (astA), toxina termolábil (LT) e toxina termoestável (STa e STb), Shiga-like toxinas (stx1 e stx2), fator citotóxico necrotizante 1 (cnf1), hemolisina (hly), produção de Aerobactina (iuc) e resistência sérica (iss). Os resultados mostraram que os isolados pertenciam a 12 sorogrupos: O7; O15; O21; O23; O54; O64; O76; O84; O88; O128; O152 e O166. Os genes de virulência encontrados foram: crl em todos os isolados, pap em 10 isolados, iss em sete isolados, csgA em cinco isolados, iuc e tsh em três isolados e eae em dois isolados. A combinação dos genes de virulência revelou 11 perfis genotípicos distintos. Todas as amostras foram negativas para os genes que codificam EAF, EAEC, K1, sfa, afa, hly, cnf, LT, STa, STb, stx1 e stx2. Estes resultados demonstraram que algumas amostras de E. coli isoladas de psitacídeos apresentam os mesmos fatores de virulência presentes nos patotipos de E. coli patogênicas para aves (APEC), uropatogênicas (UPEC) e E. coli enteropatogênicas (EPEC)

  • Sorogrupos e genes de virulência em Escherichia coli isoladas de psitacídeos
    'FapUNIFESP (SciELO)', 2015
    Co-Authors: Knöbl Terezinha, Saidenberg, André B.s, Moreno, Andrea M, Gomes, Tânia A.t, Vieira, Mônica A.m, Leite, Domingos S, Blanco, Jesus E, Ferreira, Antônio J.p
    Abstract:

    Escherichia coli isolates from 24 sick psittacine birds were serogrouped and investigated for the presence of genes encoding the following virulence factors: attaching and effacing (eae), enteropathogenic E. coli EAF plasmid (EAF), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afa), capsule K1 (neu), curli (crl, csgA), temperature-sensitive hemagglutinin (tsh), enteroaggregative heat-stable enterotoxin-1 (astA), heat-stable enterotoxin -1 heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga-like toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf1), haemolysin (hly), Aerobactin production (iuc) and serum resistance (iss). The results showed that the isolates belonged to 12 serogroups: O7; O15; O21; O23; O54; O64; O76; O84; O88; O128; O152 and O166. The virulence genes found were: crl in all isolates, pap in 10 isolates, iss in seven isolates, csgA in five isolates, iuc and tsh in three isolates and eae in two isolates. The combination of virulence genes revealed 11 different genotypic patterns. All strains were negative for genes encoding for EAF, EAEC, K1, sfa, afa, hly, cnf, LT, STa, STb, stx1 and stx2. Our findings showed that some E. coli isolated from psittacine birds present the same virulence factors as avian pathogenic E. coli (APEC), uropathogenic E. coli (UPEC) and Enteropathogenic E. coli (EPEC) pathotypes.Amostras de Escherichia coli isoladas de 24 psitacídeos doentes foram sorogrupadas e investigadas para a presença de genes que codificam os seguintes fatores de virulência: attaching e effacing (eae), plasmídeo EAF (EAF), pili associado à pielonefrite (pap), fímbria S (sfa), adesina afimbrial (afa), cápsula K1 (neu), curli (crl, csgA), hemaglutinina termosensível (tsh), enterotoxina termo-estável 1 de E. coli enteroagregativa (astA), toxina termolábil (LT) e toxina termoestável (STa e STb), Shiga-like toxinas (stx1 e stx2), fator citotóxico necrotizante 1 (cnf1), hemolisina (hly), produção de Aerobactina (iuc) e resistência sérica (iss). Os resultados mostraram que os isolados pertenciam a 12 sorogrupos: O7; O15; O21; O23; O54; O64; O76; O84; O88; O128; O152 e O166. Os genes de virulência encontrados foram: crl em todos os isolados, pap em 10 isolados, iss em sete isolados, csgA em cinco isolados, iuc e tsh em três isolados e eae em dois isolados. A combinação dos genes de virulência revelou 11 perfis genotípicos distintos. Todas as amostras foram negativas para os genes que codificam EAF, EAEC, K1, sfa, afa, hly, cnf, LT, STa, STb, stx1 e stx2. Estes resultados demonstraram que algumas amostras de E. coli isoladas de psitacídeos apresentam os mesmos fatores de virulência presentes nos patotipos de E. coli patogênicas para aves (APEC), uropatogênicas (UPEC) e E. coli enteropatogênicas (EPEC).916921Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Leite, Domingos Da Silva - One of the best experts on this subject based on the ideXlab platform.

  • Caracterização genotípica dos fatores de virulência em amostras de Escherichia coli isoladas de pacientes com cistite
    Instituto de Medicina Tropical, 2015
    Co-Authors: Tiba, Monique Ribeiro, Yano Tomomasa, Leite, Domingos Da Silva
    Abstract:

    Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (α-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (Aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.Adesinas (Fímbria P, fímbria S, fímbria do tipo 1 e a adesina afimbrial), toxinas (α-hemolisina e o fator necrosante citotóxico do tipo 1), sistemas de captação de ferro (Aerobactina), e mecanismos de defesa do hospedeiro (cápsula ou lipopolissacarídeo) são prevalentes em amostras de Escherichia coli associadas a infecções do trato urinário. O objetivo deste trabalho foi caracterizar genotipicamente 162 amostras de Escherichia coli uropatogênica (UPEC) de pacientes com cistite através do ensaio da reação em cadeia da polimerase. Foram realizados três ensaios de PCR multiplex para os seguintes fatores de virulência: papC, papE/F, alelos de papG, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, e kpsMTII. Os resultados da PCR identificaram, 158 amostras fimH (97,5%), 86 amostras kpsMTII (53,1%), 53 amostras papC/papEF/papG (32,7%), 45 amostras sfa (27,8%), 42 amostras iucD (25,9%), 41 amostras hly (25,3%), 36 amostras usp (22,2%), 30 amostras cnf-1 (18,5%) e 10 amostras afa (6,2%). Nenhuma amostra foi positiva para o gene cdtB. Neste trabalho, demonstramos que podemos encontrar múltiplas adesinas em uma única amostra e que diferentes genes de fatores de virulência podem ser encontrados em associação

  • Caracterização genotípica dos fatores de virulência em amostras de Escherichia coli isoladas de pacientes com cistite
    'FapUNIFESP (SciELO)', 2015
    Co-Authors: Tiba, Monique Ribeiro, Yano Tomomasa, Leite, Domingos Da Silva
    Abstract:

    Adhesins (P-fimbriae, S-fimbriae, type 1 fimbriae and afimbrial adhesin), toxins (α-hemolysin and cytotoxic necrotizing factor type 1), iron acquisition systems (Aerobactin) and host defense avoidance mechanisms (capsule or lipopolysaccharide) have been shown to be prevalent in Escherichia coli strains associated with urinary tract infections. In this work, 162 Uropathogenic Escherichia coli (UPEC) strains from patients with cystitis were genotypically characterized by polymerase chain reaction (PCR) assay. We developed three multiplex PCR assays for virulence-related genes papC, papE/F, papG alleles, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, and kpsMTII, all of them previously identified in UPEC strains. The PCR assay results identified 158 fimH (97.5%), 86 kpsMTII (53.1%), 53 papC/papEF/papG (32.7%), 45 sfa (27.8%), 42 iucD (25.9%), 41 hly (25.3%), 36 usp (22.2%), 30 cnf-1(18.5%) and 10 afa (6.2%) strains. No strain was positive for cdtB. In this work, we also demonstrated that adhesins may be multiple within a single strain and that several virulence genes can occur combined in association.Adesinas (Fímbria P, fímbria S, fímbria do tipo 1 e a adesina afimbrial), toxinas (α-hemolisina e o fator necrosante citotóxico do tipo 1), sistemas de captação de ferro (Aerobactina), e mecanismos de defesa do hospedeiro (cápsula ou lipopolissacarídeo) são prevalentes em amostras de Escherichia coli associadas a infecções do trato urinário. O objetivo deste trabalho foi caracterizar genotipicamente 162 amostras de Escherichia coli uropatogênica (UPEC) de pacientes com cistite através do ensaio da reação em cadeia da polimerase. Foram realizados três ensaios de PCR multiplex para os seguintes fatores de virulência: papC, papE/F, alelos de papG, fimH, sfa/foc, afaE, hly, cnf-1, usp, cdtB, iucD, e kpsMTII. Os resultados da PCR identificaram, 158 amostras fimH (97,5%), 86 amostras kpsMTII (53,1%), 53 amostras papC/papEF/papG (32,7%), 45 amostras sfa (27,8%), 42 amostras iucD (25,9%), 41 amostras hly (25,3%), 36 amostras usp (22,2%), 30 amostras cnf-1 (18,5%) e 10 amostras afa (6,2%). Nenhuma amostra foi positiva para o gene cdtB. Neste trabalho, demonstramos que podemos encontrar múltiplas adesinas em uma única amostra e que diferentes genes de fatores de virulência podem ser encontrados em associação.255260Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Furumura, Márcia T. - One of the best experts on this subject based on the ideXlab platform.

  • Características associadas à virulência de Enterococcus faecalis isolados de casos clínicos
    'FapUNIFESP (SciELO)', 2015
    Co-Authors: Furumura, Márcia T., Figueiredo, Patricia M.s., Carbonell Gleize, Darini, Ana Lucia Da Costa, Yano Tomomasa
    Abstract:

    Thirty-two clinical isolates of Enterococcus faecalis were screened for virulence factors. Twenty-four (75%) isolates produced hemolysin on Mueller-Hinton blood agar plates with sheep erythrocytes. However, the cell free heat-stable hemolysin was detected in all isolates (100%) of E. faecalis when grown in BHI-GA (BHI medium supplemented with 1% glucose and 0.03% L-arginine), but not in BHI broth alone. Twenty-four isolates (75%) produced caseinase and 23 (71.9%) lipase, but none of the isolates produced gelatinase. Fifteen (46.9%) culture filtrates caused rounding and membrane alterations with blebbing formation followed by death in HeLa and HEp-2 cells, but not in Vero cells. Thirteen isolates (40.6%) agglutinated rabbit erythrocytes, but did not produce hemagglutination in other bloods, containing or not 1% D-manose. Sixteen (50%) E. faecalis isolates adhered to HeLa cells and thirteen (40.6%) to HEp-2 cells, but all isolates adhered to polypropylene microtiter plates, indicating that clinical E. faecalis possess the ability to form biofilm in vitro. All the isolates were resistant to the bactericidal action of normal serum and did not produce Aerobactin. These findings suggest that adherence and consequently biofilm formation on ephitelial host cells are the first steps in the E. faecalis virulence and that hemolysin, lipase, caseinase and other virulence factors act as causative of human epithelial cell damages.Foram estudados os fatores de virulência de trinta e duas amostras de Enterococcus faecalis, isolados de casos clínicos. Vinte e quatro amostras (75%) produziram hemolisina em ágar sangue preparado com hemácias de carneiro. No sobrenadante da cultura em BHI nenhuma amostra produziu hemolisina, no entanto quando cultivadas em meio BHI suplementado com 1% de glucose e 0,03% de L-arginina (BHI-GA), 100% das amostras lisaram hemácias de carneiro. Vinte e quatro (75%) amostras produziram caseinase e 23 (71,9%) lipase, mas nenhuma amostra produziu gelatinase. Dezesseis (46,9%) causaram arredondamento e alteração na membrana das células, com formação de vesículas e, em seguida, a morte das células HeLa e HEp-2. Treze amostras (40,6) aglutinaram eritrócitos de coelhos, mas não aglutinaram outros eritrócitos na presença ou na ausência de 1% de D-manose. Dezesseis (50%) aderiram em células HeLa e 13 (40,6%) em células HEp-2, mas todas as amostras de E. faecalis aderiram na microplaca de polipropileno, indicando que E. faecalis isolados de casos clínicos possuem capacidade de formar biofilme in vitro. Todos os isolados mostraram-se resistentes à ação bactericida do soro normal e não produziram Aerobactina. Esses resultados sugerem que, inicialmente, a colonização ou infecção por E. faecalis ocorre pela aderência e formação de biofilme nas células epiteliais e a produção de hemolisina, lípase e caseinase pode atuar como fatores de virulência na infecção por E. faecalis.230236Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

  • Características associadas à virulência de Enterococcus faecalis isolados de casos clínicos
    Sociedade Brasileira de Microbiologia, 2015
    Co-Authors: Furumura, Márcia T., Figueiredo, Patricia M.s., Carbonell Gleize, Darini, Ana Lucia Da Costa, Yano Tomomasa
    Abstract:

    Thirty-two clinical isolates of Enterococcus faecalis were screened for virulence factors. Twenty-four (75%) isolates produced hemolysin on Mueller-Hinton blood agar plates with sheep erythrocytes. However, the cell free heat-stable hemolysin was detected in all isolates (100%) of E. faecalis when grown in BHI-GA (BHI medium supplemented with 1% glucose and 0.03% L-arginine), but not in BHI broth alone. Twenty-four isolates (75%) produced caseinase and 23 (71.9%) lipase, but none of the isolates produced gelatinase. Fifteen (46.9%) culture filtrates caused rounding and membrane alterations with blebbing formation followed by death in HeLa and HEp-2 cells, but not in Vero cells. Thirteen isolates (40.6%) agglutinated rabbit erythrocytes, but did not produce hemagglutination in other bloods, containing or not 1% D-manose. Sixteen (50%) E. faecalis isolates adhered to HeLa cells and thirteen (40.6%) to HEp-2 cells, but all isolates adhered to polypropylene microtiter plates, indicating that clinical E. faecalis possess the ability to form biofilm in vitro. All the isolates were resistant to the bactericidal action of normal serum and did not produce Aerobactin. These findings suggest that adherence and consequently biofilm formation on ephitelial host cells are the first steps in the E. faecalis virulence and that hemolysin, lipase, caseinase and other virulence factors act as causative of human epithelial cell damages.Foram estudados os fatores de virulência de trinta e duas amostras de Enterococcus faecalis, isolados de casos clínicos. Vinte e quatro amostras (75%) produziram hemolisina em ágar sangue preparado com hemácias de carneiro. No sobrenadante da cultura em BHI nenhuma amostra produziu hemolisina, no entanto quando cultivadas em meio BHI suplementado com 1% de glucose e 0,03% de L-arginina (BHI-GA), 100% das amostras lisaram hemácias de carneiro. Vinte e quatro (75%) amostras produziram caseinase e 23 (71,9%) lipase, mas nenhuma amostra produziu gelatinase. Dezesseis (46,9%) causaram arredondamento e alteração na membrana das células, com formação de vesículas e, em seguida, a morte das células HeLa e HEp-2. Treze amostras (40,6) aglutinaram eritrócitos de coelhos, mas não aglutinaram outros eritrócitos na presença ou na ausência de 1% de D-manose. Dezesseis (50%) aderiram em células HeLa e 13 (40,6%) em células HEp-2, mas todas as amostras de E. faecalis aderiram na microplaca de polipropileno, indicando que E. faecalis isolados de casos clínicos possuem capacidade de formar biofilme in vitro. Todos os isolados mostraram-se resistentes à ação bactericida do soro normal e não produziram Aerobactina. Esses resultados sugerem que, inicialmente, a colonização ou infecção por E. faecalis ocorre pela aderência e formação de biofilme nas células epiteliais e a produção de hemolisina, lípase e caseinase pode atuar como fatores de virulência na infecção por E. faecalis