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Pesquisa : D12.776.097 [Categoria DeCS]
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Id: biblio-839334
Autor: Marques, Viviane Figueira; Motta, Cássia Couto da; Soares, Bianca da Silva; Melo, Dayanne Araújo de; Coelho, Shana de Mattos de Oliveira; Coelho, Irene da Silva; Barbosa, Helene Santos; Souza, Miliane Moreira Soares de.
Título: Biofilm production and beta-lactamic resistance in Brazilian Staphylococcus aureus isolates from bovine mastitis
Fonte: Braz. j. microbiol;48(1):118-124, Jan.-Mar. 2017. tab, graf.
Idioma: en.
Projeto: CNPq; . Foundation for Research Support in the State of Rio de Janeiro.
Resumo: Abstract Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo.
Descritores: Infecções Estafilocócicas/microbiologia
Staphylococcus aureus/efeitos dos fármacos
Staphylococcus aureus/fisiologia
Biofilmes
Resistência beta-Lactâmica
Mastite Bovina/microbiologia
Antibacterianos/farmacologia
-Staphylococcus aureus/ultraestrutura
Proteínas de Bactérias/genética
Bovinos
Testes de Sensibilidade Microbiana
Transativadores/genética
Proteoma
Fatores de Virulência/genética
Proteômica/métodos
Estudos de Associação Genética
Limites: Animais
Feminino
Responsável: BR1.1 - BIREME


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Rodrigues, Dália dos Prazeres
Leal, Nilma Cintra
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Id: lil-426797
Autor: Theophilo, Grace Nazareth Diogo; Rodrigues, Dália dos Prazeres; Leal, Nilma Cintra; Hofer, Ernesto.
Título: Distribution of virulence markers in clinical and environmental Vibrio cholerae non-O1/non-O139 strains isolated in Brazil from 1991 to 2000
Fonte: Rev. Inst. Med. Trop. Säo Paulo;48(2):65-70, Mar,-Apr. 2006. tab.
Idioma: en.
Projeto: National Council for Research Support.
Resumo: Cento e setenta e nove amostras de V. cholerae não O1/não O139, isoladas de casos clínicos (139) e de meio ambiente (40), no período de 1991 a 2000 no Brasil, foram caracterizadas antigenicamente pelo National Institute of Health (Japão) e investigadas quanto ao seu potencial genético de virulência, representado pelos genes ctxA, zot, ace e tcpA. As análises fenotípicas revelaram extraordinária diversidade antigênica, com a ocorrência de 54 diferentes sorogrupos, com prevalência para O26 (7,8%). A técnica de PCR, empregada na detecção dos genes localizados no elemento genético CTX (ctxA, zot, ace) e na Ilha de Patogenicidade de Vibrio-VPI (tcpA), possibilitou a identificação de 27 cepas contendo qualquer um desses genes. O gene ctxA (codificador da sub-unidade A de CT), só foi evidenciado no sorogrupo O26, sendo também o único capaz de se apresentar com o cassete de virulência de forma intacta. Com base nos resultados obtidos deste estudo preliminar, admite-se a hipótese da potencialidade destas cepas, evoluir para raças epidêmicas.
Descritores: Proteínas de Bactérias/genética
DNA Bacteriano/genética
Genes Bacterianos/genética
/genética
VIBRIO CHOLERAE OACHONDROPLASIA/genética
Vibrio cholerae não O1/genética
-Brasil
Marcadores Genéticos
Reação em Cadeia da Polimerase
Técnica de Amplificação ao Acaso de DNA Polimórfico
/patogenicidade
VIBRIO CHOLERAE OACHONDROPLASIA/patogenicidade
Vibrio cholerae não O1/patogenicidade
Virulência/genética
Limites: Seres Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: biblio-1022610
Autor: Xiao, Qiong; Zhu, Yanbing; Li, Jiajia; Wu, Changzheng; Ni, Hui; Xiao, Anfeng.
Título: Fermentation optimization and enzyme characterization of a new ι-Carrageenase from Pseudoalteromonas carrageenovora ASY5
Fonte: Electron. j. biotechnol;32:26-34, Mar. 2018. graf, tab.
Idioma: en.
Projeto: University-Enterprise Cooperation of Fujian Province; . Public Science and Technology Research Funds Projects of Ocean; . Major Science and Technology Programs and Special Topics of Fujian Province; . Key Program of Science Foundation of Fujian Province.
Resumo: Background: A new ι-carrageenase-producing strain was screened from mangroves and authenticated as Pseudoalteromonas carrageenovora ASY5 in our laboratory. The potential application of this new strain was evaluated. Results: Medium compositions and culturing conditions in shaking flask fermentation were firstly optimized by single-factor experiment. ι-Carrageenase activity increased from 0.34 U/mL to 1.08 U/mL after test optimization. Optimal fermentation conditions were 20°C, pH 7.0, incubation time of 40 h, 15 g/L NaCl, 1.5% (w/v) yeast extract as nitrogen source, and 0.9% (w/v) ι-carrageenan as carbon source. Then, the crude ι-carrageenase was characterized. The optimum temperature and pH of the ι-carrageenase were 40°C and 8.0, respectively. The enzymatic activity at 35­40°C for 45 min retained more than 40% of the maximum activity. Meanwhile, The ι-carrageenase was inhibited by the addition of 1 mmol/L Cd2+ and Fe3+ but increased by the addition of 1 mmol/L Ag+, Ba2+, Ca2+, Co2+, Mn2+, Zn2+, Fe2+, and Al3+. The structure of oligosaccharides derived from ι-carrageenan was detected using electrospray ionization mass spectrometry (ESI-MS). The ι-carrageenase degraded ι-carrageenan, yielding disaccharides and tetrasaccharides as main products. Conclusions: The discovery and study of new ι-carrageenases are beneficial not only for the production of ι-carrageenan oligosaccharides but also for the further utilization in industrial production.
Descritores: Proteínas de Bactérias/metabolismo
Pseudoalteromonas/enzimologia
Glicosídeo Hidrolases/metabolismo
-Oligossacarídeos/biossíntese
Temperatura Ambiente
Carbono/metabolismo
Carragenina/biossíntese
Espectrometria de Massas por Ionização por Electrospray
Fermentação
Concentração de Íons de Hidrogênio
Hidrólise
Nitrogênio/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1015847
Autor: Dapkunas, Zilvinas; Baranauskas, Aurimas; Mickiene, Gitana; Pleckaityte, Milda; Zvirblis, Gintautas.
Título: Generation of dimeric single-chain antibodies neutralizing the cytolytic activity of vaginolysin
Fonte: Electron. j. biotechnol;28:52-57, July. 2017. ilus, graf, tab.
Idioma: en.
Projeto: Research Council of Lithuania.
Resumo: Background: Gardnerella vaginalis is a bacterial vaginosis (BV)-associated vaginal bacterium that produces the toxin vaginolysin (VLY). VLY is a pore-forming toxin that is suggested to be the main virulence factor of G. vaginalis. The high recurrence rate of BV and the emergence of antibiotic-resistant bacterial species demonstrate the need for the development of recombinant antibodies as novel therapeutic agents for disease treatment. Single-chain variable fragments (scFvs) generated against VLY exhibited reduced efficacy to neutralize VLY activity compared to the respective full-length antibodies. To improve the properties of scFvs, monospecific dimeric scFvs were generated by the genetic fusion of two anti-VLY scFv molecules connected by an alpha-helix-forming peptide linker. Results: N-terminal hexahistidine-tagged dimeric scFvs were constructed and produced in Escherichia coli and purified using metal chelate affinity chromatography. Inhibition of VLY-mediated human erythrocyte lysis by dimeric and monomeric scFvs was detected by in vitro hemolytic assay. The circulating half-life of purified scFvs in the blood plasma of mice was determined by ELISA. Dimeric anti-VLY scFvs showed higher neutralizing potency and extended circulating half-life than parental monomeric scFv. Conclusions: The protein obtained by the genetic fusion of two anti-VLY scFvs into a dimeric molecule exhibited improved properties in comparison with monomeric scFv. This new recombinant antibody might implement new possibilities for the prophylaxis and treatment of the diseases caused by the bacteria G. vaginalis.
Descritores: Proteínas de Bactérias/imunologia
Toxinas Bacterianas/imunologia
Anticorpos Neutralizantes/metabolismo
Anticorpos de Cadeia Única/metabolismo
-Proteínas de Bactérias/toxicidade
Toxinas Bacterianas/toxicidade
Ensaio de Imunoadsorção Enzimática
Gardnerella vaginalis
Vaginose Bacteriana
Dimerização
Fatores de Virulência
Fusão Gênica
Anticorpos Neutralizantes/imunologia
Anticorpos de Cadeia Única/imunologia
Meia-Vida
Limites: Animais
Camundongos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-889239
Autor: Wang, Jiashun; Li, Yi; Chen, Jia; Hua, Deping; Li, Yi; Deng, Hui; Li, Ying; Liang, Zhixuan; Huang, Jinhai.
Título: Rapid detection of food-borne Salmonella contamination using IMBs-qPCR method based on pagC gene
Fonte: Braz. j. microbiol;49(2):320-328, Apr.-June 2018. tab, graf.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Tianjin Science and Technology.
Resumo: Abstract Detection of Salmonella is very important to minimize the food safety risk. In this study, the recombinant PagC protein and PagC antibody were prepared and coupled with immunomagnetic beads (IMBs) to capture Salmonella cells from pork and milk samples. And then the SYBR Green qualitative PCR was developed to detect the pathogenic Salmonella. The results showed that the PagC polyclonal antiserum is of good specificity and the capture rate of 0.1 mg IMBs for Salmonella tended to be stable at the range of 70-74% corresponding to the concentrations between 101 and 104 CFU/mL. The method developed demonstrated high specificity for the positive Salmonella samples when compared to non-specific DNA samples, such as Escherichia coli, Staphylococcus aureus, Yersinia enterocolitica, and Yersinia pseudotuberculosis. The limit of detection of this assay was 18 CFU/mL. Detection and quantitative enumeration of Salmonella in samples of pork or milk shows good recoveries of 54.34% and 52.07%. In conclusion, the polyclonal antibody of recombinant PagC protein is effective to capture Salmonella from detected samples. The developed pagC antibody IMBs-qPCR method showed efficiency, sensitivity and specificity for 30 Salmonella detection, enabling detection within 10 h, which is a promising rapid method to detect Salmonella in emergency.
Descritores: Salmonella/isolamento & purificação
Contaminação de Alimentos
Separação Imunomagnética/métodos
Reação em Cadeia da Polimerase em Tempo Real/métodos
Microbiologia de Alimentos/métodos
-Salmonella/genética
Proteínas de Bactérias/imunologia
Sensibilidade e Especificidade
Leite/microbiologia
Carne/microbiologia
Anticorpos Antibacterianos/imunologia
Anticorpos Antibacterianos/metabolismo
Limites: Animais
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-889231
Autor: Silva, Paula Renata Alves da; Simões-Araújo, Jean Luiz; Vidal, Márcia Soares; Cruz, Leonardo Magalhães; Souza, Emanuel Maltempi de; Baldani, José Ivo.
Título: Draft genome sequence of Paraburkholderia tropica Ppe8 strain, a sugarcane endophytic diazotrophic bacterium
Fonte: Braz. j. microbiol;49(2):210-211, Apr.-June 2018.
Idioma: en.
Projeto: CNPq/INCT-FBN; . FAPERJ-CNE; . Embrapa; . CAPES/EMBRAPA; . José Ivo Baldani.
Resumo: Abstract Paraburkholderia tropica (syn Burkholderia tropica) are nitrogen-fixing bacteria commonly found in sugarcane. The Paraburkholderia tropica strain Ppe8 is part of the sugarcane inoculant consortium that has a beneficial effect on yield. Here, we report a draft genome sequence of this strain elucidating the mechanisms involved in its interaction mainly with Poaceae. A genome size of approximately 8.75 Mb containing 7844 protein coding genes distributed in 526 subsystems was de novo assembled with ABySS and annotated by RAST. Genes related to the nitrogen fixation process, the secretion systems (I, II, III, IV, and VI), and related to a variety of metabolic traits, such as metabolism of carbohydrates, amino acids, vitamins, and proteins, were detected, suggesting a broad metabolic capacity and possible adaptation to plant association.
Descritores: Genoma Bacteriano
Burkholderiaceae/genética
Endófitos/genética
-Proteínas de Bactérias/genética
Análise de Sequência de DNA
Biologia Computacional
Saccharum/microbiologia
Burkholderiaceae/isolamento & purificação
Redes e Vias Metabólicas/genética
Anotação de Sequência Molecular
Endófitos/isolamento & purificação
Responsável: BR1.1 - BIREME


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Id: biblio-889210
Autor: Jung, Youn Hong; Lee, Yoo Kyung; Lee, Hong Kum; Lee, Kyunghee; Im, Hana.
Título: CspB of an arctic bacterium, Polaribacter irgensii KOPRI 22228, confers extraordinary freeze-tolerance
Fonte: Braz. j. microbiol;49(1):97-103, Jan.-Mar. 2018. graf.
Idioma: en.
Projeto: Korean Government.
Resumo: ABSTRACT Freezing temperatures are a major challenge for life at the poles. Decreased membrane fluidity, uninvited secondary structure formation in nucleic acids, and protein cold-denaturation all occur at cold temperatures. Organisms adapted to polar regions possess distinct mechanisms that enable them to survive in extremely cold environments. Among the cold-induced proteins, cold shock protein (Csp) family proteins are the most prominent. A gene coding for a Csp-family protein, cspB, was cloned from an arctic bacterium, Polaribacter irgensii KOPRI 22228, and overexpression of cspB greatly increased the freeze-survival rates of Escherichia coli hosts, to a greater level than any previously reported Csp. It also suppressed the cold-sensitivity of an E. coli csp-quadruple deletion strain, BX04. Sequence analysis showed that this protein consists of a unique domain at its N-terminal end and a well conserved cold shock domain at its C-terminal end. The most common mechanism of Csp function in cold adaption is melting of the secondary structures in RNA and DNA molecules, thus facilitating transcription and translation at low temperatures. P. irgensii CspB bound to oligo(dT)-cellulose resins, suggesting single-stranded nucleic acid-binding activity. The unprecedented level of freeze-tolerance conferred by P. irgensii CspB suggests a crucial role for this protein in survival in polar environments.
Descritores: Proteínas de Bactérias/metabolismo
Flavobacteriaceae/fisiologia
Proteínas e Peptídeos de Choque Frio/metabolismo
-Regiões Árticas
Proteínas de Bactérias/genética
Regulação Bacteriana da Expressão Gênica
Temperatura Baixa
Ecossistema
Flavobacteriaceae/isolamento & purificação
Flavobacteriaceae/genética
Proteínas e Peptídeos de Choque Frio/genética
Responsável: BR1.1 - BIREME


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Id: biblio-889209
Autor: Arslan-Aydoğdu, Elif Özlem; Kimiran, Ayten.
Título: An investigation of virulence factors of Legionella pneumophila environmental isolates
Fonte: Braz. j. microbiol;49(1):189-199, Jan.-Mar. 2018. tab, graf.
Idioma: en.
Projeto: Istanbul University.
Resumo: ABSTRACT Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1) were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, phospholipase A, phospholipase C, acid phosphatase, alkaline phosphatase and lipase), hemagglutination capabilities, and pathogenicity in various host cells (Acanthamoeba castellanii ATCC 30234, mouse peritoneal macrophages and human peripheral monocytes). All the isolates of bacteria appeared to be motile and polar-flagellated and possessed the type-IV fimbria. Upon the evaluation of virulence factors, isolate 4 was found to be the most pathogenic strain, while 6 out of the 9 isolates (the isolates 1, 2, 3, 4, 5, and 7) were more virulent than the ATCC 33152 strain. The different bacterial strains exhibited differences in properties such as adhesion, penetration and reproduction in the hosts, and preferred host type. To our knowledge, this is the first study to compare the virulence of environmental L. pneumophila strains isolated in Turkey, and it provides important information relevant for understanding the epidemiology of L. pneumophila.
Descritores: Proteínas de Bactérias/metabolismo
Legionella pneumophila/metabolismo
Fatores de Virulência/metabolismo
-Proteínas de Bactérias/genética
Turquia/epidemiologia
Doença dos Legionários/microbiologia
Legionella pneumophila/isolamento & purificação
Legionella pneumophila/genética
Fatores de Virulência/genética
Microbiologia Ambiental
Macrófagos/microbiologia
Camundongos Endogâmicos BALB C
Limites: Seres Humanos
Animais
Feminino
Camundongos
Responsável: BR1.1 - BIREME


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Id: biblio-889194
Autor: Ser, Hooi-Leng; Tan, Wen-Si; Ab Mutalib, Nurul-Syakima; Yin, Wai-Fong; Chan, Kok-Gan; Goh, Bey-Hing; Lee, Learn-Han.
Título: Genome sequence of Streptomyces mangrovisoli MUSC 149T isolated from intertidal sediments
Fonte: Braz. j. microbiol;49(1):13-15, Jan.-Mar. 2018. tab, graf.
Idioma: en.
Projeto: PVC; . External Industry; . Fundamental Research Grant Scheme; . eScience; . University of Malaya; . PPP.
Resumo: ABSTRACT As the largest genus in Actinobacteria family, Streptomyces species have the ability to synthesize numerous compounds of diverse structures with bioactivities. Streptomyces mangrovisoli MUSC 149T was previously isolated as a novel streptomycete from mangrove forest in east coast of Peninsular Malaysia. The high quality draft genome of MUSC 149T comprises 9,165,825 bp with G + C content of 72.5%. Through bioinformatics analysis, 21 gene clusters identified in the genome were associated with the production of bioactive secondary metabolites. The presence of these biosynthetic gene clusters in MUSC 149T suggests the potential exploitation of the strain for production of medically important compounds.
Descritores: Streptomyces/isolamento & purificação
Genoma Bacteriano
Sedimentos Geológicos/microbiologia
-Filogenia
Streptomyces/classificação
Streptomyces/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Composição de Bases
DNA Bacteriano/genética
Dados de Sequência Molecular
Sequência de Bases
Malásia
Responsável: BR1.1 - BIREME


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Id: biblio-889188
Autor: Mares-Guia, Maria Angélica MM; Guterres, Alexandro; Rozental, Tatiana; Ferreira, Michelle dos Santos; Lemos, Elba RS.
Título: Clinical and epidemiological use of nested PCR targeting the repetitive element IS1111 associated with the transposase gene from Coxiella burnetii
Fonte: Braz. j. microbiol;49(1):138-143, Jan.-Mar. 2018. tab, graf.
Idioma: en.
Projeto: CNPq; . FAPERJ.
Resumo: ABSTRACT Q fever is a worldwide zoonosis caused by Coxiella burnetii—a small obligate intracellular Gram-negative bacterium found in a variety of animals. It is transmitted to humans by inhalation of contaminated aerosols from urine, feces, milk, amniotic fluid, placenta, abortion products, wool, and rarely by ingestion of raw milk from infected animals. Nested PCR can improve the sensitivity and specificity of testing while offering a suitable amplicon size for sequencing. Serial dilutions were performed tenfold to test the limit of detection, and the result was 10× detection of C. burnetti DNA with internal nested PCR primers relative to trans-PCR. Different biological samples were tested and identified only in nested PCR. This demonstrates the efficiency and effectiveness of the primers. Of the 19 samples, which amplify the partial sequence of C. burnetii, 12 were positive by conventional PCR and nested PCR. Seven samples—five spleen tissue samples from rodents and two tick samples—were only positive in nested PCR. With these new internal primers for trans-PCR, we demonstrate that our nested PCR assay for C. burnetii can achieve better results than conventional PCR.
Descritores: Proteínas de Bactérias/genética
Elementos de DNA Transponíveis
Reação em Cadeia da Polimerase/métodos
Coxiella burnetii/isolamento & purificação
Transposases/genética
Febre/microbiologia
-Proteínas de Bactérias/metabolismo
Coxiella burnetii/classificação
Coxiella burnetii/genética
Transposases/metabolismo
Limites: Seres Humanos
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME



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