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Id: biblio-1049755
Autor: Cruz, Stephanie Oliveira Diaz da.
Título: Construção, caracterização biológica e imunológica de vírus recombinante de vírus vacinal da febre amarela 17d, que expressam o fator de infectividade viral (vif) do vírus da imunodeficiência símia sivmac239 / Construction, biological and immunological characterization of 17d yellow fever vaccine virus recombinant virus, which express the viral infectivity factor (vif) of the simian immunodeficiency virus sivmac239.
Fonte: Rio de Janeiro; s.n; 2019. 154 p. ilus.
Idioma: pt.
Tese: Apresentada a Instituto Oswaldo Cruz para obtenção do grau de Doutor.
Resumo: O desenvolvimento de uma vacina segura e eficiente contra o HIV é considerada uma ótima medida/estratégia para controlar a epidemia mundial do HIV. Este projeto visou construir e avaliar a imunogenicidade dos vírus da febre amarela recombinante da vacina 17D que expressam antígenos do fator de infectividade viral (Vif) do vírus da imunodeficiência símia SIVmac239. O vírus da vacina da febre amarela 17D tem sido usado como vetor de protótipos de vacinas por ser um imunógeno robusto e seguro. Nosso objetivo foi avaliar vírus recombinantes da febre amarela 17D que carreiam fragmentos de genes Vif (HIV/SIV), e que foram construídos com a tecnologia do clone infeccioso e a inserção do gene de Vif na região intergênica E/NS1 do genoma do vírus vacinal da febre amarela 17D. Verificamos anteriormente que o vírus recombinante FA/Vif 1-110 original era geneticamente instável, perdendo completamente o fragmento Vif 1-110 até à quinta passagem em série em células Vero. Nós alcançamos a estabilidade genética quando deletamos a região N-terminal de Vif, que provavelmente estava interferindo na replicação do vírus da FA 17D. Chamamos de FA/Vif 42-110, o vírus que sofreu a deleção do N-terminal, e que é geneticamente estável. Mas também construímos o FA/Vif 1-110 variante, que possui o mesmo fragmento do FA/Vif 1-110 original, porém é mais estável devido as mudanças realizadas na plataforma de expressão da proteína heteróloga. Incluímos nas primeiras investigações de imunogenicidade, o FA/Vif 102-214 construído anteriormente. Nós hipotetizamos que a estabilidade genética viral poderia aumentar a imunogenicidade viral

Assim, realizamos duas imunizações em camundongos C57BL/6 com os vírus FA/Vif para a avaliação da imunogenicidade em relação à formação de células T de memória contra o vírus da FA e Vif, e indução de anticorpos neutralizantes contra o vírus da FA, gerados pelas imunizações. O vírus FA/Vif 1-110 variante e o FA/Vif 42-110 se apresentaram como bons indutores de resposta celular, porém o FA/Vif 42-110 apresentou a menor média de título de anticorpos neutralizantes. O vírus FA/Vif 102-214 apresentou bons resultados de resposta imune celular e humoral, apesar de não ter sido avaliado dentro da resposta imune celular específica. O vírus FA/Vif 1-110 variante conseguiu uma boa indução da resposta celular e humoral, e o vírus FA/Vif 1-110 original parece promissor segundo os nossos dados de resposta celular de memória efetora, apesar de ter apresentado uma média baixa de títulos de anticorpos neutralizantes. De maneira geral, os vírus FA/Vif induzem diferentes braços de resposta imune, sendo uns mais indutores de resposta celular que humoral e vice-versa. Com os vírus FA/Vif apresentando essas características em relação a resposta imune, não conseguimos relacionar a estabilidade genética com imunogenicidade, mas uma estratégia promissora para abranger os dois tipos de resposta, seria o uso de formulações virais, utilizando dois ou mais vírus FA/Vif no regime vacinal. (AU)
Descritores: Febre Amarela
Vacinas Sintéticas
Vacinas contra a AIDS
Fatores de Virulência
Limites: Seres Humanos
Responsável: BR15.1 - Biblioteca de Ciências Biomédicas
BR15.1


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Id: biblio-1039272
Autor: Azevedo, Paola Aparecida Alves; Furlan, João Pedro Rueda; Oliveira-Silva, Mariana; Nakamura-Silva, Rafael; Gomes, Carolina Nogueira; Costa, Karen Regina Carim; Stehling, Eliana Guedes; Pitondo-Silva, André.
Título: Detection of virulence and ß-lactamase encoding genes in Enterobacter aerogenes and Enterobacter cloacae clinical isolates from Brazil
Fonte: Braz. j. microbiol;49(supl.1):224-228, 2018. tab, graf.
Idioma: en.
Projeto: São Paulo Research Foundation - FAPESP.
Resumo: ABSTRACT Enterobacter cloacae and E. aerogenes have been increasingly reported as important opportunistic pathogens. In this study, a high prevalence of multi-drug resistant isolates from Brazil, harboring several β-lactamase encoding genes was found. Several virulence genes were observed in E. aerogenes, contrasting with the E. cloacae isolates which presented none.
Descritores: Proteínas de Bactérias/metabolismo
beta-Lactamases/metabolismo
Enterobacter cloacae/isolamento & purificação
Enterobacter aerogenes/isolamento & purificação
Fatores de Virulência/metabolismo
Infecções por Enterobacteriaceae/microbiologia
-Filogenia
Proteínas de Bactérias/genética
Virulência
beta-Lactamases/genética
Brasil
Testes de Sensibilidade Microbiana
Enterobacter cloacae/classificação
Enterobacter cloacae/enzimologia
Enterobacter cloacae/genética
Enterobacter aerogenes/classificação
Enterobacter aerogenes/enzimologia
Enterobacter aerogenes/genética
Fatores de Virulência/genética
Meia-Idade
Antibacterianos/farmacologia
Limites: Seres Humanos
Masculino
Feminino
Adulto
Meia-Idade
Responsável: BR1.1 - BIREME


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Avila, Fernando Antonio de
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Id: biblio-1039271
Autor: Borzi, Mariana Monezi; Cardozo, Marita Vedovelli; Oliveira, Elisabete Schirato de; Pollo, Andressa de Souza; Guastalli, Elisabete Aparecida Lopes; Santos, Luis Fernando dos; Ávila, Fernando Antonio de.
Título: Characterization of avian pathogenic Escherichia coli isolated from free-range helmeted guineafowl
Fonte: Braz. j. microbiol;49(supl.1):107-112, 2018. tab, graf.
Idioma: en.
Projeto: Fundação de Amparo à Pesquisa do Estado de São Paulo.
Resumo: Abstract Avian pathogenic Escherichia coli (APEC) isolates from apparently healthy free range helmeted guineafowl were characterized. Most of them had a high frequency of virulence associated genes, multi drug resistance and high pathogenicity. We demonstrated that helmeted guineafowl have potential to transmit antibiotic resistant APEC to other species including humans.
Descritores: Doenças das Aves/microbiologia
Escherichia coli/isolamento & purificação
Infecções por Escherichia coli/veterinária
-Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Farmacorresistência Bacteriana
Fatores de Virulência/genética
Fatores de Virulência/metabolismo
Galliformes/microbiologia
Escherichia coli/classificação
Escherichia coli/efeitos dos fármacos
Escherichia coli/genética
Infecções por Escherichia coli/microbiologia
Antibacterianos/farmacologia
Limites: Animais
Responsável: BR1.1 - BIREME


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Id: biblio-974332
Autor: Cheng, Fangjun; Li, Zhangcheng; Lan, Shimei; Liu, Wei; Li, Xiaoyan; Zhou, Zuoyong; Song, Zhenhui; Wu, Juan; Zhang, Manli; Shan, Wenjie.
Título: Characterization of Klebsiella pneumoniae associated with cattle infections in southwest China using multi-locus sequence typing (MLST), antibiotic resistance and virulence-associated gene profile analysis
Fonte: Braz. j. microbiol;49(supl.1):93-100, 2018. tab, graf.
Idioma: en.
Projeto: Fundamental Research Funds for the Central Universities; . Innovation Project for the Social Undertakings and People's Livelihood Protection in Chongqing; . Frontiers and basic research projects in Chongqing.
Resumo: Abstract Klebsiella pneumoniae is important human and animal pathogen that causes a wide spectrum of infections. In this study, isolates from cattle nasal swabs samples were identified by 16S rRNA, and to evaluate the antimicrobial susceptibility, virulence gene carrying levels, and multilocus sequence typing of K. pneumoniae isolates. 33 isolates of K. pneumoniae were isolated and identified in 213 nasal swabs samples, of which 12 were hypervirulent K. pneumoniae strains. Extended Spectrum Beta-Lactamases genes were found in 93.4% of the strains. Of which, TEM was the most prevalent (93.4%), followed by CTX-M and SHV were 57.6% and 39.4%, respectively. A main mutation pattern of quinoloneresistance-determining region, Thr83-Ieu and Asp87-Asn in gyrA and Ser87-Ile in parC, was detected in 33 K. pneumoniae isolates. All the isolates harbored at least two virulence factor genes, with ureA (97.0%) and wabG (91.0%) exhibiting high carriage rates in 33 K. pneumoniae isolates. MLST revealed 7 sequence types, of which 3 STs (2541, 2581 and 2844) were newly assigned. Using eBURST, ST2844 and ST2541 were assigned to new clonal complex 2844. Our study provides evidence and biological characteristics of K. pneumoniae isolates from cattle upper respiratory tract in Southwest China.
Descritores: Proteínas de Bactérias/genética
Infecções por Klebsiella/veterinária
Doenças dos Bovinos/microbiologia
Farmacorresistência Bacteriana Múltipla
Fatores de Virulência/genética
Klebsiella pneumoniae/isolamento & purificação
Klebsiella pneumoniae/efeitos dos fármacos
Antibacterianos/farmacologia
-Proteínas de Bactérias/metabolismo
Infecções por Klebsiella/microbiologia
China
Fatores de Virulência/metabolismo
Tipagem de Sequências Multilocus
Klebsiella pneumoniae/genética
Klebsiella pneumoniae/metabolismo
Limites: Animais
Bovinos
Responsável: BR1.1 - BIREME


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Id: biblio-839325
Autor: Gomes, Tânia A. T; Elias, Waldir P; Scaletsky, Isabel C. A; Guth, Beatriz E. C; Rodrigues, Juliana F; Piazza, Roxane M. F; Ferreira, Luís C. S; Martinez, Marina B.
Título: Diarrheagenic Escherichia coli
Fonte: Braz. j. microbiol;47(supl.1):3-30, Oct.-Dec. 2016.
Idioma: en.
Resumo: ABSTRACT Most Escherichia coli strains live harmlessly in the intestines and rarely cause disease in healthy individuals. Nonetheless, a number of pathogenic strains can cause diarrhea or extraintestinal diseases both in healthy and immunocompromised individuals. Diarrheal illnesses are a severe public health problem and a major cause of morbidity and mortality in infants and young children, especially in developing countries. E. coli strains that cause diarrhea have evolved by acquiring, through horizontal gene transfer, a particular set of characteristics that have successfully persisted in the host. According to the group of virulence determinants acquired, specific combinations were formed determining the currently known E. coli pathotypes, which are collectively known as diarrheagenic E. coli. In this review, we have gathered information on current definitions, serotypes, lineages, virulence mechanisms, epidemiology, and diagnosis of the major diarrheagenic E. coli pathotypes.
Descritores: Diarreia/diagnóstico
Diarreia/microbiologia
Escherichia coli/classificação
Escherichia coli/fisiologia
Infecções por Escherichia coli/diagnóstico
Infecções por Escherichia coli/microbiologia
-Prevalência
Fatores de Virulência/genética
Diarreia/epidemiologia
Escherichia coli/patogenicidade
Infecções por Escherichia coli/epidemiologia
Limites: Seres Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-839365
Autor: Gonçalves, Iara Rossi; Dantas, Raquel Cristina Cavalcanti; Ferreira, Melina Lorraine; Batistão, Deivid William da Fonseca; Gontijo-Filho, Paulo Pinto; Ribas, Rosineide Marques.
Título: Carbapenem-resistant Pseudomonas aeruginosa: association with virulence genes and biofilm formation
Fonte: Braz. j. microbiol;48(2):211-217, April.-June 2017. tab, graf.
Idioma: en.
Resumo: Abstract Pseudomonas aeruginosa is an opportunistic pathogen that causes frequently nosocomial infections, currently becoming more difficult to treat due to the various resistance mechanisms and different virulence factors. The purpose of this study was to determine the risk factors independently associated with the development of bacteremia by carbapenem-resistant P. aeruginosa, the frequency of virulence genes in metallo-β-lactamases producers and to evaluate their ability to produce biofilm. We conducted a case–control study in the Uberlândia Federal University – Hospital Clinic, Brazil. Polymerase Chain Reaction was performed for metallo-β-lactamases and virulence genes. Adhesion and biofilm assays were done by quantitative tests. Among the 157 strains analyzed, 73.9% were multidrug-resistant, 43.9% were resistant to carbapenems, 16.1% were phenotypically positive for metallo-β-lactamases, and of these, 10.7% were positive for blaSPM gene and 5.3% positive for blaVIM. The multivariable analysis showed that mechanical ventilation, enteral/nasogastric tubes, primary bacteremia with unknown focus, and inappropriate therapy were independent risk factors associated with bacteremia. All tested strains were characterized as strongly biofilm producers. A higher mortality was found among patients with bacteremia by carbapenem-resistant P. aeruginosa strains, associated independently with extrinsic risk factors, however it was not evident the association with the presence of virulence and metallo-β-lactamases genes.
Descritores: Pseudomonas aeruginosa/genética
Infecções por Pseudomonas/epidemiologia
Proteínas de Bactérias/genética
beta-Lactamases/genética
Bacteriemia/epidemiologia
Biofilmes/crescimento & desenvolvimento
Resistência beta-Lactâmica
Fatores de Virulência/genética
-Pseudomonas aeruginosa/isolamento & purificação
Pseudomonas aeruginosa/efeitos dos fármacos
Pseudomonas aeruginosa/enzimologia
Infecções por Pseudomonas/microbiologia
Proteínas de Bactérias/análise
beta-Lactamases/análise
Brasil/epidemiologia
Estudos de Casos e Controles
Análise de Sobrevida
Reação em Cadeia da Polimerase
Fatores de Risco
Bacteriemia/microbiologia
Limites: Seres Humanos
Masculino
Feminino
Adulto
Meia-Idade
Idoso
Responsável: BR1.1 - BIREME


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Id: biblio-828186
Autor: Ellepola, Arjuna N. B; Samaranayake, L. P; Khan, Z. U.
Título: Extracellular phospholipase production of oral Candida albicans isolates from smokers, diabetics, asthmatics, denture wearers and healthy individuals following brief exposure to polyene, echinocandin and azole antimycotics
Fonte: Braz. j. microbiol;47(4):911-916, Oct.-Dec. 2016. tab.
Idioma: en.
Projeto: Kuwait University Research Grant.
Resumo: Abstract Objective Candida albicans is the primary causative agent of oral candidosis, and one of its key virulent attributes is considered to be its ability to produce extracellular phospholipases that facilitate cellular invasion. Oral candidosis can be treated with polyenes, and azoles, and the more recently introduced echinocandins. However, once administered, the intraoral concentration of these drugs tend to be sub-therapeutic and rather transient due to factors such as the diluent effect of saliva and cleansing effect of the oral musculature. Hence, intra-orally, the pathogenic yeasts may undergo a brief exposure to antifungal drugs. We, therefore, evaluated the phospholipase production of oral C. albicans isolates following brief exposure to sub-therapeutic concentrations of the foregoing antifungals. Materials and methods Fifty C. albicans oral isolates obtained from smokers, diabetics, asthmatics using steroid inhalers, partial denture wearers and healthy individuals were exposed to sub-therapeutic concentrations of nystatin, amphotericin B, caspofungin, ketoconazole and fluconazole for one hour. Thereafter the drugs were removed and the phospholipase production was determined by a plate assay using an egg yolk-agar medium. Results The phospholipase production of these isolates was significantly suppressed with a percentage reduction of 10.65, 12.14, 11.45 and 6.40% following exposure to nystatin, amphotericin B, caspofungin and ketoconazole, respectively. This suppression was not significant following exposure to fluconazole. Conclusions Despite the sub-therapeutic, intra oral, bioavailability of polyenes, echinocandins and ketoconazole, they are likely to produce a persistent antifungal effect by suppressing phospholipase production, which is a key virulent attribute of this common pathogenic yeast.
Descritores: Fosfolipases/biossíntese
Candida albicans/efeitos dos fármacos
Candida albicans/metabolismo
Candidíase Bucal/microbiologia
Candidíase Bucal/tratamento farmacológico
Antifúngicos/farmacologia
-Polienos/uso terapêutico
Polienos/farmacologia
Azóis/uso terapêutico
Azóis/farmacologia
Candida albicans/isolamento & purificação
Candida albicans/patogenicidade
Fumar
Testes de Sensibilidade Microbiana
Dentaduras
Fatores de Virulência
Diabetes Mellitus
Ativação Enzimática
Espaço Extracelular
Equinocandinas/farmacologia
Antifúngicos/uso terapêutico
Limites: Seres Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-1039047
Autor: Kaskatepe, Banu; Yilmaz, Betul Sever; Acikara, Ozlem Bahadir; Iscan, Gulcin Saltan; Vlainic, Josipa; Kosalec, Ivan.
Título: Antifungal activity of some Sternbergia taxa: effects on germ tube and biofilm formation
Fonte: Braz. J. Pharm. Sci. (Online);55:e17200, 2019. tab, graf.
Idioma: en.
Resumo: Natural products are rapidly becoming the primary sources of novel antimicrobial agents, as resistance to existing antimicrobial agents is increasing. Apart from determining the antimicrobial activity of natural products, it is also important to understand their effects on the virulence factors of microorganisms. This study aimed to determine the antimicrobial activity of Sternbergia species prevalent in Turkey and investigate their role in the inhibition of germination tube and biofilm formation, both of which are known to be important virulence factors of Candida albicans. The antimicrobial activities of the plant extracts were evaluated using bore-plate and broth microdilution method. The extracts' capacity to inhibit the formation of the germ-tube was also evaluated. The findings of our study revealed that Sternbergia lutea, Sternbergia vernalis possessed antimicrobial activities, with MIC values ranging between 0.048 mg/mL and 0.39 mg/mL. The highest antimicrobial activity was observed against Candida dubliniensis (0.048 mg/mL). While evaluating the inhibition of fungal germination activities, S. vernalis extract (at a concentration of 0.09 mg/mL) was found to be the most effective against C. albicans ATCC 90028 strain. The results also indicated that S. vernalis extracts at sub-MIC levels inhibited germ tube formation and modulated the tail-length of germinated cells, both of which are important virulence factors of C. albicans. Furthermore, the inhibition of biofilm-formation was also investigated, and it was found that two Sternbergia spp. extracts at or below MIC levels inhibited biofilm formation.
Descritores: Biofilmes/efeitos dos fármacos
Amaryllidaceae/classificação
Anti-Infecciosos/análise
-Candida albicans
Extratos Vegetais/efeitos adversos
Fatores de Virulência
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas


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Id: biblio-869031
Autor: Rodríguez Acosta, F; Carpinelli, L; Basualdo, W; Castro, H; Quiñonez, B; Argüello, R; Guillén, RM.
Título: Frecuencia de genes que codifican factores de virulencia en staphylococcus aureus aislados de niños que concurrieron al hospital general pediátrico niños de acosta ñú, durante el año 2010 / Frequency of gens that codify virulence factors in staphylococcus aureus isolated from children attending the niños de acosta ñú pediatric general hospital in 2010
Fonte: Mem. Inst. Invest. Cienc. Salud (Impr.);13(1):58-66, abr. 2015. ilus, tab.
Idioma: es.
Resumo: Staphylococcus aureus es un microorganismo con habilidad de infectar diferentes tejidos celulares, por portar genes que le confieren resistencia a antibióticos, factores de virulencia y su plasticidad genética, que podrían contribuir a una progresión rápida y complicada de la enfermedad. El Paraguay no cuenta con datos epidemiológicos que indiquen los factores de virulencia que presentan las cepas de S. aureus, por lo que el objetivo del trabajo fue determinar un perfil de virulencia detectando los genes codificantes de: hemolisinas α y β,enterotoxinas A, B, C, D, H y toxinas exfoliativas A y B. Este estudio observacional descriptivo de corte transverso, con muestreo no probabilístico de casos consecutivos, incluyó 50 aislados de S. aureus obtenidos a partir de muestras clínicas de secreciones de piel, partes blandas o líquidos corporales de pacientes menores de 17 años que concurrieron al Hospital General Pediátrico Niños de Acosta Ñú durante el año 2.010. Las reacciones de PCR incluyeron la detección de los genes: sea+seb+sec+ADNr16S, hlA+hlB, eta+etb, sed y seh. El 82% de los aislados provenía de niños que presentaron cuadros clínicos compatibles con infecciones de piel y partes blandas y el 18% de cuadros clínicos graves como sepsis, osteomielitis y neumonías. Los aislados contaban con datos de portación de Leucocidina de Panton-Valentine, el cual fue el factor de virulencia más frecuentemente detectado (58%), seguido de las hemolisinas alfa (16%) y beta (8%). Las enterotoxinas y las toxinas exfoliativas fueron menos frecuentes (0-2%), y no se detectaron genes codificantes de las enterotoxinas C y D.

Staphylococcus aureus is a pathogen that has the ability to successfully infect differenttissues, because it carries genes that confer antibiotic resistance, virulence factors and itshigh genetic plasticity, that could contribute to a quick and complicated diseaseprogression. Paraguay does not have epidemiological data indicating the virulence factorspresented in S. aureus strains. Therefore, the aim of this study was to determine thevirulence profile by molecular methods detecting the codifying genes of: α and β hemolysin, enterotoxins A, B, C, D, H and exfoliative toxins A and B. This descriptiveobservational study with non-probability sampling of consecutives cases, included 50 S.aureus isolates obtained from clinical specimens from skin secretions, soft tissue or bodyfluids of patients younger than 17 years who attended the Niños de Acosta Ñú PediatricGeneral Hospital in 2010. The PCR reactions included the detection of the followinggenes: sea+seb+sec+ADNr16S, hlA+hlB, eta+etb, sed and seh. The 82% of the isolatescame from children skin and soft tissue infections and 18% came from invasive diseasessuch as sepsis, osteomyelitis and pneumonia. The Panton Valentine leukocidin, whichdata was previously obtained, was the most frequently virulence factor detected (58%),followed by alpha (16%) and beta (8%) hemolysins. Enterotoxins and exfoliative toxinswere less frequent (0-2%) and the enterotoxins C and D genes were not detected.
Descritores: Fatores de Virulência
Staphylococcus aureus/isolamento & purificação
-Reação em Cadeia da Polimerase
Limites: Seres Humanos
Masculino
Adolescente
Feminino
Recém-Nascido
Lactente
Pré-Escolar
Criança
Responsável: PY3.1 - Biblioteca


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Id: biblio-839393
Autor: Yu, Yi; Chang, De; Xu, Huiwen; Zhang, Xuelin; Pan, Lei; Xu, Chou; Huang, Bing; Zhou, Hong; Li, Jia; Guo, Jun; Liu, Changting.
Título: The virulence of Streptococcus pneumoniae partially depends on dprA
Fonte: Braz. j. microbiol;48(2):225-231, April.-June 2017. graf.
Idioma: en.
Projeto: National Basic Research Program of China; . National Major Scientific and Technological Special Project for \"Significant New Drugs Development\"; . National Natural Science Foundation of China; . Basic Research Program of General Hospital of Chinese People's Armed Police Forces.
Resumo: Abstract Streptococcus pneumoniae is one of the most frequent opportunistic pathogens worldwide. DNA processing protein A (DprA) is an important factor involved in bacterial uptake and DNA integration into bacterial genome, but its role in S. pneumoniae virulence remains unclear. The aim of this study was to characterize the effects of the pneumococcal dprA gene on the pathogenesis of S. pneumoniae. To construct a dprA-deficient pneumococcal strain, the dprA gene of the S. pneumoniae strain D39 was inactivated. The virulence of this dprA-deficient strain, designated ΔD39, was compared with that of the wild-type strain by evaluating their respective capabilities to adhere to human pulmonary epithelial cells (PEC-A549) and by analyzing their choline-binding protein expression levels. In addition, the expression profiles of genes associated with virulence and host survival assays were also conducted with the mutant and the wild-type strain. Our results indicate that the capability of ΔD39 to adhere to the PEC-A549 airway cells was significantly lower (p < 0.01) compared with D39. Additionally, the 100-KD choline-binding protein was not detected in ΔD39. The addition of competence-stimulating peptide (CSP) lead to a significantly reduction of psaA mRNA expression in the dprA-deficient mutant and an increased level of psaA transcripts in the wild-type strain (p < 0.01). The median survival time of mice intraperitoneally infected with ΔD39 was significantly higher (p < 0.01) than that of mice infected with D39. The results of this study suggest that DprA has a significant effect on virulence characteristics of S. pneumoniae by influencing the expression of choline-binding protein and PsaA.
Descritores: Infecções Pneumocócicas/patologia
Streptococcus pneumoniae/patogenicidade
Proteínas de Bactérias/metabolismo
Aderência Bacteriana
Fatores de Virulência/análise
Proteínas de Membrana/metabolismo
-Infecções Pneumocócicas/microbiologia
Streptococcus pneumoniae/genética
Proteínas de Bactérias/análise
Proteínas de Bactérias/genética
Análise de Sobrevida
Linhagem Celular
Fatores de Virulência/genética
Modelos Animais de Doenças
Células Epiteliais/microbiologia
Técnicas de Inativação de Genes
Proteínas de Membrana/genética
Camundongos
Limites: Seres Humanos
Animais
Responsável: BR1.1 - BIREME



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BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde