350 results on '"Lopes, Ana Catarina"'
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152. Multidrug resistance genes, including blaKPC and blaCTX-M-2, among Klebsiella pneumoniae isolated in Recife, Brazil
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Cabral, Adriane Borges, primary, Melo, Rita de Cássia de Andrade, additional, Maciel, Maria Amélia Vieira, additional, and Lopes, Ana Catarina Souza, additional
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- 2012
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153. First Report of KPC-Producing Pseudomonas aeruginosa in Brazil
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Jácome, Paula Regina Luna de Araújo, primary, Alves, Lílian Rodrigues, additional, Cabral, Adriane Borges, additional, Lopes, Ana Catarina S., additional, and Maciel, Maria Amélia Vieira, additional
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- 2012
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154. Colonização pelo Staphylococcus aureus em profissionais de enfermagem de um hospital escola de Pernambuco
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Silva, Eduardo Caetano Brandão Ferreira da, primary, Samico, Thammy Moura, additional, Cardoso, Rodrigo Rosa, additional, Rabelo, Marcelle Aquino, additional, Bezerra Neto, Armando Monteiro, additional, Melo, Fábio Lopes de, additional, Lopes, Ana Catarina de Souza, additional, Aca, Ivanize da Silva, additional, and Maciel, Maria Amélia Vieira, additional
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- 2012
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155. Enhancement of the Dielectric Constant and Thermal Properties of α-Poly(vinylidene fluoride)/Zeolite Nanocomposites
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Lopes, Ana Catarina, primary, Silva, Marco P., additional, Gonçalves, Renato, additional, Pereira, Manuel F. R., additional, Botelho, Gabriela, additional, Fonseca, António M., additional, Lanceros-Mendez, Senenxtu, additional, and Neves, Isabel C., additional
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- 2010
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156. blaCTX-M-2 and blaCTX-M-28 extended-spectrum β-lactamase genes and class 1 integrons in clinical isolates of Klebsiella pneumoniae from Brazil
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Lopes, Ana Catarina S, primary, Veras, Dyana Leal, additional, Lima, Alexsandra Mariá S, additional, Melo, Rita de Cássia Andrade, additional, and Ayala, Juan, additional
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- 2010
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157. Vigilância epidemiológica e susceptibilidade de Staphylococcus aureus em profissionais de saúde de um hospital de referência: Uma avaliação inicial
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Silva, Eduardo Caetano Brandão Ferreira da, primary, Maciel, Maria Amélia Vieira, additional, Melo, Fábio Lopes de, additional, Lopes, Ana Catarina de Souza, additional, and Aca, Ivanize da Silva, additional
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- 2010
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158. Análise epidemiológica de isolados clínicos de Pseudomonas aeruginosa provenientes de hospital universitário
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Pires, Eduardo José Valença Cordeiro, primary, Silva Júnior, Valdemir Vicente da, additional, Lopes, Ana Catarina de Souza, additional, Veras, Dyana Leal, additional, Leite, Larissa Espíndola, additional, and Maciel, Maria Amélia Vieira, additional
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- 2009
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159. Application of PCR ribotyping and tDNA-PCR for Klebsiella pneumoniae identification
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Lopes, Ana Catarina S, primary, Rodrigues, Juliana Falcão, additional, Clementino, Maysa BM, additional, Miranda, Catia AC, additional, Nascimento, Ana Paula A, additional, and Morais Júnior, Marcos Antônio de, additional
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- 2007
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160. Molecular typing of Klebsiella pneumoniae isolates from public hospitals in Recife, Brazil
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de Souza Lopes, Ana Catarina, primary, Falcão Rodrigues, Juliana, additional, and Antônio de Morais Júnior, Marcos, additional
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- 2005
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161. Prevalence of the bla Gene in Klebsiella pneumoniae Isolates Obtained from Hospital and Community Infections and from the Microbiota of Healthy Individuals in Recife, Brazil.
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Veras, Dyana Leal, Alves, Luiz Carlos, Brayner, Fábio André, Guedes, Duschinka Ribeiro Duarte, Maciel, Maria Amélia Vieira, Rocha, Cíntia Renata Costa, and de Souza Lopes, Ana Catarina
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KLEBSIELLA pneumoniae ,NOSOCOMIAL infections ,NUCLEOTIDE sequence - Abstract
The aim of this study was to determine the prevalence of the bla gene in Klebsiella pneumoniae isolates from hospital and community infections and from the normal microbiota of healthy individuals in Recife, PE, Brazil. Fifty-two K. pneumoniae isolates were analyzed regarding the presence of the bla gene, using PCR, and eight isolates were analyzed by DNA sequencing. This gene was detected in 16 isolates from hospital infections, four from community infections, and nine from the normal microbiota. This was the first study to find the bla gene in K. pneumoniae isolates from the normal microbiota. Through DNA sequencing of eight K. pneumoniae isolates from hospital and community infections, with a resistance phenotype indicative of extended-spectrum β-lactamase production, a new SHV variant named SHV-122 was found. We also detected the presence of bla, bla, bla, and bla. The results show that in Recife, Brazil, K. pneumoniae isolates that presented resistance to oxyimino-β-lactams had high prevalence and diversity of the bla gene. We also conclude that there was a high presence of the bla gene among isolates from the normal microbiota of healthy individuals. [ABSTRACT FROM AUTHOR]
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- 2011
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162. Multidrug-resistant Klebsiella aerogenesclinical isolates from Brazil carrying IncQ1 plasmids containing the blaKPC-2gene associated with non-Tn4401elements (NTEKPC-IId)
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Bispo Beltrão, Elizabeth Maria, de Oliveira, Érica Maria, dos Santos Vasconcelos, Crhisllane Rafaele, Cabral, Adriane Borges, Rezende, Antônio Mauro, and Souza Lopes, Ana Catarina
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- 2020
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163. Emergence of blaVIM-2, blaNDM-1, blaIMP-7and blaGES-1in blaKPC-2-harbouring Pseudomonas aeruginosaisolates in Brazil
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Scavuzzi, Alexsandra Maria Lima, Beltrão, Elizabeth Maria Bispo, Firmo, Elza Ferreira, de Oliveira, Érica Maria, Beserra, Fernanda Gomes, and Lopes, Ana Catarina de Souza
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- 2019
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164. O papel da arte na reabilitação urbana. Uma análise comparativa
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Lopes, Ana Catarina Pinto de Sousa da Cruz, Farinha, João, and Amado, Miguel P.
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Cultura ,Desenvolvimento social ,Desenvolvimento sustentável ,Ambiente urbano ,Reabilitação ,Arte - Abstract
Uma das problemáticas mais prementes nas cidades europeias, caracteriza-se pela degradação física, social, económica e ambiental dos seus centros históricos. No entanto, as estratégias tradicionais de reabilitação e combate a estes problemas são muitas vezes ineficazes, sendo necessário procurar novas formas de superar tais problemas, que devem ser enquadradas numa política de Desenvolvimento Sustentável. A criatividade e as actividades artísticas podem desempenhar um papel significativo na resolução destes problemas, através da ocupação de edifícios devolutos. Com base numa análise comparativa de quatro casos de estudo: LxFactory, em Lisboa; Ateneu Popular 9 Barris, em Barcelona; 59 Rivoli, em Paris; Kunsthaus Tacheles, em Berlim; foi possível constatar que a reabilitação pela arte pode produzir um efeito de renovação social e económica no espaço e sua envolvente, criando novas oportunidades económicas locais, emprego, novos percursos turísticos, atracção de novos habitantes, entre outros. Considerando o enquadramento que, actualmente, a reabilitação tem como acção de cariz sustentável, particularmente ao nível da dimensão ambiental, associá-la às actividades artísticas, criativas ou culturais, pode permitir responder às dimensões social e económica. A introdução de novas dinâmicas e vivências em espaços desocupados ou devolutos, permite ainda a valorização económica dos imoveis, constituindo um factor de regeneração urbana. A proposta de um modelo de avaliação da sustentabilidade de casos de reabilitação pela arte pode fundamentar a sua criação, permitindo que estes sejam replicados, com os benefícios que lhes estão associados. A aplicação do modelo pode portanto, disponibilizar informações sobre a capacidade de geração de influências positivas, das intervenções de reabilitação pela arte, ao nível do Desenvolvimento Sustentável, potenciando a aceitação destes projectos por parte dos vários agentes que compõem a cidade e viabilizando a sua difusão para outros espaços urbanos com necessidades de reabilitação.
165. A deeper EPR spectroscopy insight of Cr(VI) and Cr(III) species capture/reduction by Zr-MOFs
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G. Saiza, Paula, Fernández de Luis, Roberto, Lezama, Luis, Iglesias, Naroa, Fidalgo, Arkaitz, Larrea, Edurne S., Lopes, Ana Catarina, and Arriortua, María Isabel
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Chromium adsorption ,13. Climate action ,Metal Organic Frameworks - Abstract
Heavy metals (HMs) are the most common and dangerous pollutants present in water. Among the different methods used for HMs removal, adsorption is one of the best options since its cost-effectivity and easy operation. In this regard, Metal Organic Frameworks (MOFs) adsorbents are gaining interest in that field due to their unique characteristics such high porosity, easy tunability and high chemical stability. In order to increase the adsorption capacity and selectivity of that adsorbents different modifications of the structure are carried out. In that work, six different UiO66 Zr-crystal frameworks have been used to study the effect of incorporating hydroxyl and amine groups within the organic linkers, as well as of the presence of defective positions on the adsorption capacity of Cr(VI) and Cr(III) species. Results (Figs. 1-7) shows that, the generation of defective points increase the density of chemisorption points for chromate anions (Cr(VI)) while for cationic Cr(III) species the density of hydroxyl or amine groups is the fact that governs the adsorption capacity.  
166. A deeper EPR spectroscopy insight of Cr(VI) and Cr(III) species capture/reduction by Zr-MOFs
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G. Saiza, Paula, Fernández de Luis, Roberto, Lezama, Luis, Iglesias, Naroa, Fidalgo, Arkaitz, Larrea, Edurne S., Lopes, Ana Catarina, and Arriortua, María Isabel
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Chromium adsorption ,13. Climate action ,Metal Organic Frameworks - Abstract
Heavy metals (HMs) are the most common and dangerous pollutants present in water. Among the different methods used for HMs removal, adsorption is one of the best options since its cost-effectivity and easy operation. In this regard, Metal Organic Frameworks (MOFs) adsorbents are gaining interest in that field due to their unique characteristics such high porosity, easy tunability and high chemical stability. In order to increase the adsorption capacity and selectivity of that adsorbents different modifications of the structure are carried out. In that work, six different UiO66 Zr-crystal frameworks have been used to study the effect of incorporating hydroxyl and amine groups within the organic linkers, as well as of the presence of defective positions on the adsorption capacity of Cr(VI) and Cr(III) species. Results (Figs. 1-7) shows that, the generation of defective points increase the density of chemisorption points for chromate anions (Cr(VI)) while for cationic Cr(III) species the density of hydroxyl or amine groups is the fact that governs the adsorption capacity.
167. Infuence of zeolite structure and chemistry on the electrical response and crystallization phase of poly(vinylidene fluoride)
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Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica, Lopes, Ana Catarina, Caparrós Vázquez, Cristina Maria, Ferdov, Stanislav, Lanceros Méndez, Senentxu, Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica, Lopes, Ana Catarina, Caparrós Vázquez, Cristina Maria, Ferdov, Stanislav, and Lanceros Méndez, Senentxu
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Zeolites with framework types LTL, LTA, FAU, and MFI were synthesized and used as fillers to prepare PVDF/zeolite composites. The obtained composites showed structural and electrical dependence on the pore system and chemical content of the inorganic host. The larger polymer-zeolite electrostatic interactions of the Y and A zeolites lead the polymer to crystallize in the electroactive ¿-phase, which in the case of the L zeolite is prevented due to the reduced interaction area. The solvent and water encapsulation ability of the zeolite as well as improve of the dielectric response of the composite is directly related to the Si/Al ratio, leading zeolites with lower Si/Al ratios to larger dielectric responses and encapsulation efficiencies in the composites. These effects show also some dependency on the dimensionality of the pore system; the zeolite L-containing 1D channels showing superior dielectric performance than the 3D pore system of zeolite Y., Peer Reviewed, Postprint (published version)
168. First Report of KPC-Producing Pseudomonas aeruginosain Brazil
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Jácome, Paula Regina Luna de Araújo, Alves, Lílian Rodrigues, Cabral, Adriane Borges, Lopes, Ana Catarina S., and Maciel, Maria Amélia Vieira
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- 2012
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169. Environmental sensors based on geometrically modified magnetoelastic resonators functionalized with MOFs
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González Saiz, Paula, Teixeira Castro Lopes, Ana Catarina, and Arriortua Marcaida, María Isabel
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magnetism ,compuestos ,crystallography ,composites ,magnetismo ,cristalografía - Abstract
250 p. La detección de compuestos tóxicos presentes en el agua y en el aire resulta crucial para asegurar la salud de la población. Los sensores magnetoelásticos permiten una detección rápida, precisa, barata y a distancia. Sin embargo, ciertas propiedades como la sensibilidad y la selectividad de los mismos deben ser optimizadas. La presente tesis doctoral se centra en mejorar las capacidades de este tipo de sensores. En primer lugar, se analiza el efecto de la geometría del resonador magnetoelástico en propiedades tales como la sensibilidad a la masa, observándose que ésta puede aumentar considerablemente utilizando sensores triangulares o romboédricos en lugar de rectangulares. En segundo lugar, se analiza la posibilidad de utilizar materiales de tipo MOF (Metal Organic Frameworks) como capa activa en estos sensores y se investigan distintos procesos de funcionalización para integrar estos materiales en los resonadores magnetoelásticos. Finalmente, se analiza el uso de los sensores desarrollados para la detección de ciertos compuestos como metales pesados o compuestos orgánicos volátiles. Los resultados obtenidos muestran una mejora en el funcionamiento de estos sensores al introducir estas modificaciones, lo que resulta crucial para el futuro desarrollo de sensores inalámbricos basados en resonadores magnetoelásticos para las llamadas ¿ciudades inteligentes¿, en línea con los objetivos planteados en el programa de investigación e innovación de la Unión Europea (Horizonte Europa) y en los de desarrollo sostenible (Agenda 2030). BC materials: Basque Center for materials applications & nanostructures
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- 2020
170. Investigação de genes de resistência a antimicrobianos em isolados clínicos de enterobactérias multidroga-resistentes provenientes de hospitais de Recife-PE : avaliação morfológica e ultraestrutural após ação antimicrobianos e análise de antibioticoterapia in vitro
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FIRMO, Elza Ferreira, LOPES, Ana Catarina de Souza, and VERAS, Dyana Leal
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Bactérias gram-negativas ,Resistência microbiana a medicamentos ,Combinação antimicrobiana ,Alterações ultraestruturais ,Sinergismo farmacológico - Abstract
CAPES O objetivo desse estudo foi investigar a ocorrência de diferentes genes de resistência aos carbapenêmicos, aos aminoglicosídeos, e as polimixinas, em isolados clínicos MDR de enterobactérias provenientes de três hospitais de Recife- PE entre 2016 e 2018. Como também determinar, in vitro, a sinergia e a atividade bactericida das combinações de polimixina B, meropenem, amicacina e gentamicina, além de investigar a alterações ultraestruturais causadas por essas associações. Inicialmente, isolados clínicos de enterobactérias resistentes a pelo menos um aminoglicosídeo e a um carbapenêmico foram selecionadas para a investigação da ocorrência de genes codificadores de carbapenemases (blaOXA-48, blaNDM, blaKPC, blaGES, blaVIM, blaIMP e blaSME), enzimas modificadoras de aminoglicosídeos (EMAs) (aac(3)-Ia, aac(3)-IIa, aac(6')-Ib, ant (2")-Ia e aph(3')-VI), metilases 16S rRNA (armA, rmtD e rmtG) e o gene mcr-1. Esses isolados foram genotipados pela técnica ERIC-PCR (enterobacterial repetitive intergenic consensus polymerase chain reaction), a concentração inibitória mínima foi determinada por microdiluição em caldo e a detecção desses genes foram realizadas por PCR e sequenciamento. Foram obtidos no total 35 isolados, provenientes de diferentes espécimes, sendo: 16 isolados de Klebsiella pneumoniae, 10 de Proteus mirabilis e 09 de Serratia marcescens uma alta variabilidade genética entre as espécies. Dentre eles, 89% apresentaram o gene blaKPC-2, 26% apresentaram o gene blaNDM-1 e 97% apresentaram genes EMAs. Esse é o primeiro relato publicado da associação dos genes blaNDM-1, blaKPC-2 e genes EMAs em isolados clínicos de K. pneumoniae, P. mirabilis e S. marcescens no Brasil. Após a caracterização fenotípica e genotípica, foram selecionados quatro isolados portadores do gene blaNDM-1 e resistentes a polimixina B, para determinação in vitro da ação das combinações antimicrobianas. Os isolados (K7R2 e K11R2) foram submetidos a combinações de polimixina B, meropenem, amicacina e gentamicina para investigação das atividades sinérgica e bactericida por meio das técnicas de checkerboard e time-kill. Polimixina B combinada com meropenem e com amicacina foram mais eficazes contra esses isolados. Os isolados P3R3 e S9U foram submetidos a combinações de meropenem com amicacina e gentamicina, além disso, foram selecionados para avaliação de alterações ultraestruturais causadas por essas combinações, através da microscopia eletrônica. Em ambos isolados a combinação de meropenem e gentamicina foi mais eficaz, porém no isolado P3R3 essa combinação foi bactericida com eliminação das células bacterianas após 6h da utilização desses antimicrobianos. Alterações ultraestruturais mais intensas foram observadas quando as células bacterianas foram expostas a combinações sinérgicas e bactericidas. Pode-se concluir que apesar da circulação de uma nova carbapenemase (NDM) em Recife-PE, o uso de antimicrobianos já conhecidos na prática clínica, como polimixina B, amicacina, meropenem e gentamicina, em associação, podem ser uma alternativa para a antibioticoterapia e para impedir a disseminação de espécies MDR. Adicionalmente, dados obtidos neste estudo alertam para a disseminação de genes de resistência aos carbapenêmicos e aminoglicosídeos entre isolados clínicos e relacionados clonalmente. O que pode indicar uma alta probabilidade de pacientes estarem servindo de reservatórios para bactérias portadoras dos genes blaNDM-1 e blaKPC-2 e outros determinantes de resistência. The objective of this study was to investigate the occurrence of different resistance genes to carbapenems, aminoglycosides, and polymyxins, in MDR clinical isolates from enterobacteria from three hospitals in Recife-PE between 2016 and 2018. How to also determine, in vitro, the synergy and bactericidal activity of the combinations of polymyxin B, meropenem, amikacin and gentamicin, in addition to investigating ultrastructural changes caused by these associations. Initially, clinical isolates of enterobacteria resistant to at least one aminoglycoside and one carbapenem were selected to investigate the occurrence of genes encoding carbapenemases (blaOXA-48, blaNDM, blaKPC, blaGES, blaVIM, blaIMP e blaSME), aminoglycoside modifying enzymes (AMEs) (aac(3)-Ia, aac(3)-IIa, aac(6')-Ib, ant (2")-Ia e aph(3')-VI), 16S rRNA methylases (armA, rmtD e rmtG) and the mcr-1 gene. These isolates were genotyped by the ERIC-PCR technique (enterobacterial repetitive intergenic consensus polymerase chain reaction), the minimum inhibitory concentration was determined by microdilution in broth and the detection of these genes was performed by PCR and sequencing. A total of 35 isolates, obtained from different specimens, were obtained: 16 isolates from Klebsiella pneumoniae, 10 from Proteus mirabilis and 09 from Serratia marcescens, with a high genetic variability between species. Among them, 89% had the blaKPC-2 gene, 26% had the blaNDM-1 gene and 97% had AMEs genes. This is the first published report of the association of blaNDM-1, blaKPC-2 and AME genes in clinical isolates of K. pneumoniae, P. mirabilis and S. marcescens in Brazil. After phenotypic and genotypic characterization, four isolates carrying the blaNDM-1 gene and resistant to polymyxin B were selected for in vitro determination of the action of antimicrobial combinations. The isolates (K7R2 and K11R2) were subjected to combinations of polymyxin B, meropenem, amikacin and gentamicin to investigate synergistic and bactericidal activities using checkerboard and time-kill techniques. Polymyxin B combined with meropenem and amikacin were more effective against these isolates. The isolates P3R3 and S9U were subjected to combinations of meropenem with amikacin and gentamicin, in addition, these isolates were selected for evaluation of morphological and ultrastructural changes caused by these combinations, using electron microscopy. In both isolates, the combination of meropenem and gentamicin was more effective, but in isolate P3R3 this combination was bactericidal with elimination of bacterial cells after 6 hours of using these antimicrobials. By electron microscopy, more intense ultrastructural changes were observed when the bacterial cells were exposed to synergistic and bactericidal combinations. It can be concluded that despite the circulation of a new carbapenemase (NDM) in Recife-PE, often associated with KPC and EMAs, the use of antimicrobials already known in clinical practice, such as polymyxin B, amikacin, meropenem and gentamicin, in combination, may be an alternative to antibiotic therapy and to prevent the spread of MDR species.Additionally,data obtained in this study alert to the spread of genes for resistance to carbapenems and aminoglycosides among clinical and clonally related isolates. This may indicate a high probability that patients are serving as reservoirs for bacteria carrying the blaNDM-1 and blaKPC-2 genes and other resistance determinants.
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- 2020
171. Caracterização do ambiente genético de Klebsiella pneumoniae multidroga resistente: gene blakpc, transposon e grupo de incompatibilidade plasmidial
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LIMA, Giselle Jucá de, LOPES, Ana Catarina de Souza, and SCAVUZZI, Alexsandra Maria Lima
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Klebsiella pneumoniae ,Plasmídeos ,Transposon - Abstract
CAPES Klebsiella pneumoniae produtora da enzima carbapenemase (KPC) tem sido agente de infecções relacionadas à assistência à saúde (IRAS) em diversos países, inclusive no Brasil. Em todos estudos o gene blaKPC foi encontrado em um elemento genético móvel, um transposon, pertencente a família Tn3 (Tn4401), comumente localizado em plasmídeos. Portanto, o objetivo deste estudo foi realizar a caracterização molecular de plasmídeos, grupo de incompatibilidade plasmidial (incs), transposon e ambiente genético de blaKPC-2 em isolados clínicos de K. pneumoniae multidroga resistentes provenientes de pacientes de dois hospitais de Recife-PE. Foram selecionados cinco isolados clínicos de K. pneumoniae multi-droga resistentes (MDR), suspeitos de serem produtores de KPC e os mesmos foram submetidos a análise do sequenciamento do DNA plasmidial e confirmação por PCR de genes de resistência a antimicrobianos identificados. Na análise do ambiente genético plasmidial, de todos os isolados, foi detectado o gene blaKPC-2 inserido no transposon Tn4401, com uma deleção da sequência de inserção ISKpn7 e dos genes istA, istB e transposase (TnpA), revelando uma nova variante do Tn4401, semelhante à variante descrita recentemente em E. aerogenes em Recife-PE. Próximo ao gene blaKPC-2 foram encontrados genes de mobilidade e replicação. As ferramentas de bioinformática detectaram um plasmídeo pequeno e mobilizável, pertencente ao grupo de incompatibilidade plasmidial IncQ. Para confirmação desse achado foram realizadas PCR uniplex para o IncQ, e os mesmos foram amplificados com sucesso em todos os isolados. Esse achado difere de estudos anteriores que geralmente encontravam o blaKPC-2 em plasmídeos IncN, IncLM e IncA/C. No isolado K10R2, além da presença do IncQ, foi encontrado um gene de resistência ao metal pesado arsênio, juntamente a presença de regiões tra codificante a um plasmídeo conjugativo, porém não tipável, confirmando a presença de mais de um plasmídeo nessa bactéria. Todos esses achados revelam a dinâmica do ambiente genético plasmidial do gene blaKPC- 2 encontrado em uma nova variante do transposon Tn4401 e em um plasmídeo, identificado como IncQ1. Enfatizando a continuada recombinação e evolução dos elementos genéticos móveis plasmídeos e tranposons, potencializando assim a disseminação de diferentes genes de resistência em isolados de K. pneumoniae no ambiente hospitalar. Klebsiella pneumoniae producer of enzyme carbapenemase KPC has been a conductor of infectious diseases related to health assistance in several countries, including Brazil, and in all studies the blaKPC gene was found inserted in a mobile genetic element, a transposon, belonging to the family Tn3 (Tn4401), commonly located in plasmids. This study aimed to perform the molecular characterization of plasmids, plasmid incompatibility group (Incs), transposon and blaKPC-2 genetic environment in multi-drug resistant clinical isolates of K. pneumoniae from different patients from two hospitals in Recife-PE. Five multi-drug resistant clinical isolates of K. pneumoniae were selected and subjected to analysis of plasmid DNA sequencing. The analysis of the plasmid genetic environment in all the isolates exhibited the blaKPC-2 gene inserted in a transposon Tn4401, with a deletion of the ISKpn7 insertion sequence, the istA, istB genes and the transposase (TnpA), revealing a new variant of Tn4401, similar to the variant described recently in E. aerogenes in Recife-PE. Nexto to the blaKPC-2 gene were found mobility and replication genes, bioinformatics tools detected a small, mobilizable plasmid belonging to the group of plasmid incompatibility IncQ. To confirm this finding, uniplex PCR for incQ was performed, and it was successfully amplified in all isolates. This finding differs greatly from previous studies that generally found blaKPC-2 in different plasmids as incN, IncLM and IncA / C. The K10R2 isolate, in addition to the presence of IncQ, was found a heavy metal resistance arsenic gene, moreover that there is the presence of tra regions specific to a conjugative plasmid but it was a non typing plasmid. It should be noted that the presence of more than one plasmid in a bacterial cell favors the further dispersion of resistance genes as well as may increase the pathogenic capacity of this bacterium. All of these findings reveal the dynamics of the plasmidial environment of the blaKPC-2 gene found in a new variant of transposon Tn4401 and in a plasmid identified as IncQ. Emphasizing the continuous recombination and evolution of the mobile genetic elements plasmids and tranposons, thus potentiating the dissemination of different resistance genes in K. pneumoniae isolates in the hospital environment.
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- 2018
172. Uso de pontos quânticos para análise da atividade in vitro do inibidor de bomba de efluxo carbonil cianeto-3-clorofenilhidrazona sobre a formação de biofilme e perfil de susceptibilidade de isolados clínicos de Pseudomonas aeruginosa
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SILVA JÚNIOR, Valdemir Vicente da, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina de Souza
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Pseudomonas aeruginosa ,Pontos quânticos ,Farmacorresistência bacteriana múltipla ,Carbonil cianeto m-clorofenil hidrazona - Abstract
Pseudomonas aeruginosa é uma bactéria Gram-negativa responsável por causar infecções oportunistas em pacientes imunocomprometidos. Os sistemas de efluxo multidroga são importantes para o surgimento de fenótipos multidroga-resistentes (MDR), que tem dificultado o tratamento das infecções por P. aeruginosa. O presente estudo teve como objetivo analisar a ação do inibidor de bomba de efluxo carbonil cianeto-3-clorofenilhidrazona (CCCP) frente a isolados clínicos de P. aeruginosa multidroga-resistentes provenientes de hospitais pernambucanos. Oito isolados MDR foram selecionados para o estudo, obtidos dos laboratórios de bacteriologia de três hospitais diferentes: um Hospital Universitário (UH), um Hospital terciário (TH) e um Hospital oncológico (CH), entre 2006 e 2017. Os isolados foram estocados no Laboratório de Bacteriologia e Biologia Molecular (LBBM) do Departamento de Medicina Tropical da Universidade Federal de Pernambuco. Reação em cadeia da polimerase (PCR) foi realizada para pesquisa dos genes mexA e mexE codificantes da proteína canal dos sistemas de efluxo MexAB-OprM e MexEF-OprN, além dos genes codificantes de enzimas beta-lactamases blaᴋᴘᴄ, blasᴘᴍ e blaɢᴇs. O método de disco-difusão determinou os perfis de susceptibilidade para sete antimicrobianos diferentes na ausência e na presença de CCCP. As concentrações inibitórias mínimas (CIMs) para amicacina, meropenem e polimixina B foram obtidas através de microdiluições na ausência e na presença de CCCP. Um isolado foi selecionado para realização de microscopia de fluorescência após incubação com um bioconjugado de pontos quânticos de CdTe/meropenem na ausência e na presença do CCCP. Encontramos os genes mexA e mexE simultaneamente em todos os isolados analisados. Os genes blaᴋᴘᴄ, blasᴘᴍ₋₁ e blaɢᴇs também foram detectados (dois, um e três isolados, respectivamente) não havendo simultaneidade desses genes numa mesma bactéria. A adição do CCCP ocasionou aumento do halo de inibição em dois isolados, o primeiro para o imipenem (12 mm para 22 mm), o segundo isolado para ticarcilina/clavulanato e aztreonam (0 mm para 10 mm e 10 mm para 18 mm, respectivamente). Um terceiro isolado apresentou colônias crescidas no interior dos halos de inibição indicativas da presença do fenômeno de heterorresistência, essas colônias supostamente heterorresistentes desapareceram após a adição do CCCP para os antibióticos cefepime, aztreonam, gentamicina e ciprofloxacina. Após adição do CCCP dois isolados alteraram as CIMs para amicacina (128 µg/mL para 64 µg/mL e mais de 256 µg/mL para 32 µg/mL), para meropenem, um isolado diminuiu a CIM (32 µg/mL para 16 µg/mL) e outro aumentou (8 µg/mL para 16 µg/mL). Quanto à polimixina B todos os isolados tiveram as CIMs diminuídas na presença do inibidor sendo quatro isolados de 4 µg/mL para 2 µg/mL, três de 8 µg/mL para 4 µg/mL e um de 4 µg/mL para 1 µg/mL. A análise através de microscopia de fluorescência do bioconjugado de pontos quânticos com meropenem demonstrou diminuição na formação de biofilme e alteração no perfil de marcação da bactéria após adição de CCCP. Esses resultados sugerem que o CCCP pode ser apontado como um novo potencial agente usado em sinergia com os antibióticos para o tratamento de infecções por P. aeruginosa, além de poderem ser determinantes de resistência antimicrobiana através de sistemas de efluxo. Pseudomonas aeruginosa is a Gram-negative bacterium responsible by causing opportunistic infections in immunocompromised patients. Multidrug efflux systems are important for emergence of multidrug-resistant (MDR) phenotypes which has been hindered treatment of P.aeruginosa infections. The present study aimed to analyze the action of carbonyl cyanide-3-chlorophenylhydrazone efflux pump inhibitor (CCCP) against multidrug-resistant P. aeruginosa clinical isolates from hospitals in Pernambuco. Eight MDR isolates were selected for study, collected from bacteriology laboratories from different hospitals: a University Hospital (UH), a Tertiary Hospital (HT) and a Cancer Hospital (CH) between 2006 and 2017. The isolates were stored in Laboratório de Bacteriologia e Biologia Molecular (LBBM) do Departamento de Medicina Tropical da Universidade Federal de Pernambuco. Polymerase chain reaction (PCR) was performed to investigate mexA and mexE genes codifying channel-protein on MexAB-OprM and MexEF-OprN efflux systems, besides to betalactamase enzyme coding by blaᴋᴘᴄ, blasᴘᴍ₁ and blaGES. The susceptibility profiles for seven different antimicrobials were determined by disck-diffusion method in the absence and presence of CCCP. Minimum inhibitory concentrations (MICs) for amikacin, meropenem and polymyxin B were obtained by microdilution in the absence and presence of CCCP. A single isolate was selected to fluorescence microscopy analysis after incubation with CdTe quantum dots / meropenem bioconjugate in the absence and presence of CCCP. The mexA and mexE genes were detected, simultaneously in all analyzed isolates. The blaᴋᴘᴄ, blasᴘᴍ₁ and blaɢᴇs two, one and three isolates, respectively), these genes were no identified in the same bacterium. The CCCP addition caused an increase in inhibition halo for two isolates, the first for imipenem (12 mm for 22 mm), the second for ticarcillin/clavulanate and aztreonam (0 mm for 10 mm and 10 mm for 18 mm, respectively). A third isolate presented colonies grown within the inhibition halos indicative of presence of heteroresistance phenomenon, these supposedly heteroresistant colonies disappeared after the CCCP addition to antibiotics cefepime, aztreonam, gentamicin and ciprofloxacin. After CCCP addition, two isolates changed the MICs for amikacin (128 μg/ mL to 64 μg/ mL and > 256 μg / mL to 32 μg / mL), for meropenem one isolate decreased MIC (32 μg / mL for 16 μg / mL) and another increased (8 μg / mL to 16 μg / mL). Concerning to polymyxin B, all isolates had MICs decreased in the presence of inhibitor: four isolates from 4 μg / mL to 2 μg / mL, three from 8 μg / mL to 4 μg / mL and one from 4 μg / mL to 1 μg / ml. Fluorescence microscopy of quantum dot bioconjugates with meropenem showed a decrease in biofilm formation and a change in the labeling profile of bacteria after CCCP addition. These results demonstrate that CCCP can be identified as a new potential agent used in synergy with antibiotics for treatment of P.aeruginosa infections, and may be determinants of antimicrobial resistance by efflux systems.
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- 2018
173. The essential oil of the leaves of Verbesina macrophylla (Cass.) S.F.Blake has antimicrobial, anti-inflammatory and antipyretic activities and is toxicologically safe.
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de Veras, Bruno Oliveira, de Oliveira, João Ricardhis Saturnino, de Menezes Lima, Vera Lúcia, do Amaral Ferraz Navarro, Daniela Maria, de Oliveira Farias de Aguiar, Júlio César Ribeiro, de Medeiros Moura, Geovanna Maria, da Silva, José Wellinton, de Assis, Caio Rodrigo Dias, Gorlach-Lira, Krystyna, de Assis, Priscilla Anne Castro, de Souza Barbosa, Jorge Irapuan, de Melo, Maria Rita Cabral Sales, de Oliveira, Maria Betânia Melo, da Silva, Márcia Vanusa, and de Souza Lopes, Ana Catarina
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ANTI-infective agents , *ANTI-inflammatory agents , *CYTOKINES , *DRUG toxicity , *ESSENTIAL oils , *GAS chromatography , *HEMOLYSIS & hemolysins , *INTERLEUKINS , *LEAVES , *MASS spectrometry , *MEDICINAL plants , *MICE , *PATIENT safety , *TUMOR necrosis factors , *PLANT extracts , *NONOPIOID analgesics , *PHARMACODYNAMICS - Abstract
Verbesina macrophylla (Cass.) S.F.Blake is a medicinal plant from South America, popularly known as "asa de peixe", "asa de peixe branco", "cambará branco" or "cambará guaçu", being used by traditional communities for its healing powers in the form of teas, infusions, liqueurs and extracts, for the treatment of bacterial and fungal infections of the urinary and respiratory tracts, such as kidney problems, bronchitis, inflammation and fever. However, none of the ethnopharmacological properties has been scientifically evaluated. Based on the ethnopharmacological use of the species, this study investigated the chemical composition, and for the first time acute toxicity, hemolytic, antimicrobial, anti-inflammatory and antipyretic activities of the essential oil from leaves of V. macrophylla. The essential oil was obtained from the leaves by hydrodistillation (HD), being characterized by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography coupled to flame ionization detection (GC-FID). The antimicrobial activity was evaluated by the broth microdilution technique in bacteria and fungi that cause infections of the respiratory and urinary tract, and toxicological safety regarding hemolytic activity on human red blood cells (hRBCs), and acute toxicity in mice. The anti-inflammatory activity was evaluated by the model carrageenan-induced peritonitis with quantification of the levels of TNF-α and IL-1β in the intraperitoneal fluid, and ear edema induced by croton oil. The antipyretic activity evaluated in mice with pyrexia induced by yeast. The extraction of essential oil by hydrodistillation (HD) showed a yield of 0.33 ± 0.04%, with its composition constituted mainly by sesquiterpenes of hydrocarbons (94.00%). The essential oil demonstrated antibacterial and antifungal activity, with a low rate of hemolysis in human red blood cells (hRBCs) and no clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD 50 is greater than 5000 mg/kg; p.o. The essential oil demonstrated anti-inflammatory activity reducing levels of pro-inflammatory cytokines TNF-α (38.83%, 72.42% and 73.52%) and IL-1β (37.70%, 75.92% and 87.71%), and ear edema by 49.53%, 85.04% and 94.39% at concentrations of 4, 40 and 400 mg/kg, respectively. The antipyretic activity presented by the essential oil is statistically similar to dipyrone. The set of results obtained, validates the main activities attributed to the traditional use of Verbesina macrophylla (Cass.) S.F.Blake. These data add industrial value to the species, considering that the antimicrobial, anti-inflammatory and antipyretic activities present results similar to the drugs already used also presenting safety. The results suggest that essential oil from V. macrophylla may be used by industry for the development of drugs with natural antimicrobial, anti-inflammatory and antipyretic effect. Image 1 [ABSTRACT FROM AUTHOR]
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- 2021
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- View/download PDF
174. Fatores de risco para a mortalidade em pacientes infectados por enterobactérias portadoras do gene blaᴋᴘᴄ internados em um hospital terciário de Recife-PE
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MEDEIROS, Renata Daniele Amaral de and LOPES, Ana Catarina de Souza
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Genes MDR ,Enterobacteriaceae ,Infecção hospitalar - Abstract
Bacilos gram-negativos multidroga resistente (MDR) são cada vez mais comuns causando infecções relacionadas a assistência a saúde (IRAS) e associadas a altas taxas de mortalidade, hospitalizações mais longas, aumento dos custos de internação somado a resistência bacteriana. Gêneros da família Enterobacteriaceae são as mais representativas com relação ao aparecimento da resistência (blaᴋᴘᴄ) principalmente aos antimicrobianos β-lactâmicos. Diante deste cenário, diversos estudos investigam os preditores de mortalidade em pacientes infectados pelo gene blaᴋᴘᴄ em todo o mundo, contudo há uma divergência entre os resultados encontrados. Portanto, este estudo tem por objetivo identificar a associação entre os fatores de risco e a mortalidade em pacientes internados num hospital terciário de Recife-PE em 2016 e infectados por enterobactérias portadoras do gene blaᴋᴘᴄ. O estudo foi realizado em um hospital terciário, classificado como grande porte. Trata-se de um estudo observacional, do tipo coorte prospectivo. Houve a aplicação de um questionário aos pacientes incluídos na pesquisa e o acompanhamento de cada um durou 30 dias consecutivos até o desfecho (morte ou sobrevida), partindo-se dos pacientes expostos (pacientes infectados por enterobactérias portadoras do gene blaᴋᴘᴄ) e os não expostos (pacientes infectados por enterobactérias, porém não portadoras do gene blaᴋᴘᴄ). As bactérias analisadas foram Proteus mirabilis, Serratia marcescens, Klebsiella pnemoniae, E. coli. Na análise da população estudada, diversos fatores apresentaram diferenças significativas como: o agente infeccioso, o sexo, o número de complicações pós-internamento, a exposição dos pacientes a diversos ambientes hospitalares que já tiveram casos de bactérias com o gene blaᴋᴘᴄ, submissão a hemodiálise, ter Diabetes Mellitus, utilizar 4 ou mais antimicrobianos, dentre eles as quinolonas, os glicopeptídeos, os carbapenêmicos, a polimixina e ter isolados de outros microrganismos de forma concomitante durante a internação. Contudo, quando analisado os fatores de risco em associação bivariada com o óbito (desfecho estudado) os fatores significativos foram: a submissão a hemodiálise (3,81 de risco (RP = 4,81), ter Diabetes Mellitus (5,58 de risco (RP = 6,58), ter sido co-infectado por outros microrganismos (fungos ou demais bacilos/cocos) risco 3,72 (RP = 4,72) e ter utilizado em específico os antimicrobianos polimixina e amicacina risco de 7,93 (RP=8,93) e 4,46 (5,46), respectivamente. Diante deste cenário, outros estudos diferem em relação as especificidades. Outros estudos demonstraram que as quinolonas e o metronidazol são preditores determinantes para a mortalidade, assim como o uso prévio de qualquer antimicrobiano. Outros apontam qualquer procedimento invasivo, sem especificidade e a doença renal como principal comorbidade preditora para mortalidade. A partir desse estudo observacional de um único centro, conseguiu-se desenhar uma estrutura direcionada a uma tomada de decisão clínica mais preventiva em relação a região estudada. Diante do exposto, os cuidados devem ser tomados acerca de sempre preservar a função renal e desta forma evitar processos hemodialíticos futuros, deve-se também usar de forma racional os antimicrobianos, principalmente os utilizados para bactérias MDR e evitar a exposição dos pacientes infectados a ambientes limpos. Bacilos gram-negativos multidroga resistente (MDR) son cada vez más comunes causando infecciones relacionadas con la asistencia a la salud (IRAS) y asociadas a altas tasas de mortalidad, hospitalizaciones más largas, aumento de los costos de internación sumado a la resistencia bacteriana. Los géneros de la familia Enterobacteriaceae son los más representativos con relación a la aparición de la resistencia (blaKPC) principalmente a los antimicrobianos β-lactámicos. En este escenario, diversos estudios investigan los predictores de mortalidad en pacientes infectados por el gen blaKPC en todo el mundo, sin embargo hay una divergencia entre los resultados encontrados. Por lo tanto, este estudio tiene por objetivo identificar la asociación entre los factores de riesgo y la mortalidad en pacientes internados en un hospital terciario de Recife-PE en 2016 e infectados por enterobacterias portadoras del gen blaKPC. El estudio fue realizado en un hospital terciario, clasificado como gran porte. Se trata de un estudio observacional, del tipo cohorte prospectivo. La aplicación de un cuestionario a los pacientes incluidos en la investigación y el seguimiento de cada uno duró 30 días consecutivos hasta el desenlace (muerte o sobrevida), partiendo de los pacientes expuestos (pacientes infectados por enterobacterias portadoras del gen blaKPC) y los no expuestos (pacientes infectados por enterobacterias, pero no portadoras del gen blaKPC). Las bacterias analizadas fueron Proteus mirabilis, Serratia marcescens, Klebsiella pnemoniae, E. coli. En el análisis de la población estudiada, diversos factores presentaron diferencias significativas como: el agente infeccioso, el sexo, el número de complicaciones post-internamiento, la exposición de los pacientes a diversos ambientes hospitalarios que ya tuvieron casos de bacterias con el gen blaKPC, sumisión a hemodiálisis , tener Diabetes Mellitus, utilizar 4 o más antimicrobianos, entre ellos las quinolonas, los glicopeptídeos, los carbapenémicos, la polimixina y tener aislados de otros microorganismos de forma concomitante durante la internación. Sin embargo, cuando se analizaron los factores de riesgo en asociación bivariada con el óbito (desenlace estudiado) los factores significativos fueron: la sumisión a hemodiálisis (3,81 de riesgo (RP = 4,81), tener Diabetes Mellitus (5,58 de riesgo (RP = 6,58), haber sido co-infectado por otros microorganismos (hongos o demás bacilos / cocos) riesgo 3,72 (RP = 4,72) y haber utilizado en específico los antimicrobianos polimixina y amicacina riesgo de 7,93 De acuerdo con la normativa vigente en el país de origen, en el caso de que se produzca un cambio en la calidad del producto, el uso previo de cualquier antimicrobiano, otros apuntan a cualquier procedimiento invasivo, sin especificidad y la enfermedad renal como principal comorbilidad predictora de mortalidad. A partir de ese estudio observacional de un único centro, se logró diseñar una estructura dirigida a una toma de decisión clínica más preventiva en relación a la región estudiada. En el presente estudio se debe tener en cuenta que los cuidados deben tomarse sobre siempre preservar la función renal y de esta forma evitar procesos hemodiálticos futuros, se debe también utilizar de forma racional los antimicrobianos, principalmente los utilizados para bacterias MDR y evitar la exposición de los pacientes infectados a ambientes limpia. Gram-negative multidrug-resistant (MDR) rods are increasingly common causing health care-related infections (IRAS) and associated with high mortality ratesmicrorganismo, longer hospitalizations, increased hospitalization costs and bacterial resistance. Genuses of the Enterobacteriaceae family are the most representative in relation to the appearance of resistance (blaKPC) mainly to β-lactam antibiotics. In this scenario, several studies investigate the predictors of mortality in patients infected with the blaKPC gene worldwide, however, there is a divergence between the results found. This study aims to identify the association between risk factors and mortality in patients hospitalized in a tertiary hospital in Recife-PE in 2016 and infected with enterobacteria carrying the blaKPC gene. The study was performed in a tertiary hospital located in Recife-PE, classified as large. This is an observational, prospective cohort study. A questionnaire was applied to the patients included in the study and the follow-up of each one lasted 30 consecutive days until the outcome (death or survival), starting from the patients exposed (patients infected with enterobacteria carriers of the blaKPC gene) and the non-exposed (patients infected by enterobacteria, but not carriers of the blaKPC gene). The bacteria analyzed were Proteus mirabilis, Serratia marcescens, Klebsiella pneumoniae. In the analysis of the studied population, several factors showed significant differences such as: the infectious agent, sex, the number of post-hospitalization complications, the exposure of patients to various hospital environments that had previously had cases of bacteria with the blaKPC gene, submitted to hemodialysis , have Diabetes Mellitus, use 4 or more antibiotics, among them quinolones, glycopeptides, carbapenems, polymyxin and to have isolates of other microorganisms concomitantly during hospitalization. However, when we analyzed the risk factors in bivariate association with death (outcome studied) the significant factors were:: hemodialysis (3.81 at risk (PR = 4.81), Diabetes Mellitus (5.58 (PR = 6.58), having been co-infected by other microorganisms (fungi or other bacilli / cocci) risk 3.72 (PR = 4.72) and used in particular the antibiotics polimixina and amicacina risk of 7, 93 (RP = 8.93) and 4.46 (5.46), respectively. Faced with this scenario, other studies differ in relation to specificities. Other studies have shown that quinolones and metronidazole are determinant predictors for mortality, as well as the prior use of any antibiotic. Others point to any invasive procedure, with no specificity and renal disease as the main predictive comorbidity for mortality. From this observational study of a single center, it was possible to design a structure directed to a more preventive clinical decision making in relation to the studied region. In view of the foregoing, care must be taken to always preserve renal function and thus avoid future hemodialytic processes, one must also use rationally antimicrobials, especially those used for MDR bacteria and avoid exposure of infected patients to environments clean.
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- 2017
175. Caracterização de grupos de incompatibilidade plasmidial e ambiente genético de blaKPC-2, blaSCO-1, sul2 e aph (3')-VIi em isolados clínicos de Enterobacter aerogenes
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BELTRÃO, Elizabeth Maria Bispo and LOPES, Ana Catarina de Souza
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Enterobacter aerogenes ,Plasmídeos ,Transposon - Abstract
CAPES Enterobacter aerogenes é uma enterobactéria frequentemente envolvida em Infecções Relacionadas a Assistência à Saúde, que pode apresentar resistência às diferentes classes de antimicrobianos. Há evidências de que a aquisição de resistência nessa espécie, se deve à disseminação plasmidial, juntamente com transposons, entre bactérias gram-negativas. Portanto, o objetivo deste trabalho foi realizar a caracterização de grupos de incompatibilidade plasmidiais (Incs) e determinar o ambiente genético de blaKPC-2 e outros genes de resistência presentes em plasmídeos de isolados clínicos de E. aerogenes provenientes de um hospital público de Recife-PE. Foram selecionados 17 isolados clínicos de E. aerogenes, carreadores do gene blaKPC, e os mesmos foram submetidos a PCR para os grupos Incs A/C, L/M e HI-2. Foram selecionados dois isolados de E. aerogenes para o sequenciamento do DNA plasmidial, por serem provenientes de septicemia em pacientes de UTI e portadores do gene blaKPC. Todos os 17 isolados foram positivos na PCR para os Incs A/C e L/M, enquanto o Inc HI-2 não foi detectado. Na análise do sequenciamento plasmidial além da confirmação da presença do gene blaKPC-2, também foram encontrados os genes de resistência, blaSCO-1, sul2 e aph (3')-VIi. O gene blaKPC-2 foi encontrado inserido no transposon Tn4401 com uma deleção da sequência de inserção ISKpn7 e dos genes istA, istB e transposase (TnpA). Próximo ao gene blaKPC-2 também foi encontrado o gene aph (3')-VIi. Com relação ao gene blaSCO-1, este foi encontrado próximo a uma transposase tnpAtnpR, sendo este o primeiro relato do gene blaSCO-1 em isolados de E. aerogenes. A presença de diferentes genes de resistência, inseridos em plasmídeos Inc A/C₂ e L/M, confirmam a importância de se monitorar a circulação dos plasmídeos e analisar as sequências gênicas dessas estruturas. Deve-se destacar que embora o gene blaKPC-2 tenha sido codificado dentro do elemento Tn4401, foram encontradas diferentes características estruturais, notadamente a perda de tnpA e ISKpn7, indicando uma nova versão do Tn4401 (a ser denominada Tn4401i). Essas características podem fazer com que o transposon Tn4401 perca sua capacidade de transposição, pois as sequências de inserção são essenciais para a sua mobilidade. Estes achados enfatizam ainda a continuada recombinação e evolução de plasmídeos e do elemento Tn4401 que contém o gene blaKPC-2, e o potencial de disseminação plasmidial de diferentes genes de resistência por E. aerogenes no ambiente hospitalar. Enterobacter aerogenes is a frequently enterobacterium involved in healthcare-associated infections, it may be resistant to different antimicrobials agents classes. There is evidence of resistance acquisition in this species, due to plasmid propagation, along with transposons between gram-negative bacteria. This study aimed to characterize Plasmid Incompatibility Groups (Incs) and to determine the genetic region of blaKPC-2 and other resistance genes present in plasmids from clinical isolates of E. aerogenes from a public hospital in Recife/PE. Seventeen clinical isolates of E. aerogenes carriers of the blaKPC gene were selected and subjected to PCR for the Incs A/C, L/M and HI-2 groups. Only two E. aerogenes isolates were selected for the sequencing of the plasmid DNA by carriers blaKPC-2 gene and from septicemia in ICU patients. All seventeen strains were PCR positive for Incs A/C and L/M, while Inc HI-2 was not detected. Plasmid sequencing confirmed the presence of the blaKPC-2 gene, and resistance genes, blaSCO-1, sul2 and aph (3')-Vi were also found. blaKPC-2 gene was found inserted in Tn4401 transposon with deletion of the ISKpn7 insertion sequence and the istA, istB gene and a transposase (TnpA). Next to the blaKPC-2 gene was also found the aph (3')-VIi gene. Related to the blaSCO-1 gene, it was found next to a tnpAtnpR transposase, which is the first report of the blaSCO-1 gene in E. aerogenes isolates. Presence of different resistance genes inserted in Inc A/C₂ and L/M plasmids confirm the importance of monitoring the circulation of plasmids and analyzing their gene sequences. It is important to note that although the blaKPC-2 gene was encoded within the Tn4401 element, different structural characteristics were found; noting that the loss of tnpA and ISKpn7 indicated a new version of Tn4401 (will be called Tn4401i). These characteristics may do the transposon Tn4401 to lose its transposing ability, since the insertion sequences are essential for its mobility. These findings emphasize the continuous recombination and evolution of plasmids and Tn4401 element that contains the blaKPC-2 gene, in addition to the potential for plasmidial dissemination of different resistance genes by E. aerogenes in the hospital environment.
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- 2017
176. Perfil de resistência, virulência e pesquisa de sistemas de efluxo em isolados clínicos de Acinetobacter spp. provenientes de pacientes oncológicos
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ALVES, Lilian Rodrigues, MACIEL, Maria Amelia Vieira, and LOPES, Ana Catarina de Souza
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Resistência a multiplos medicamentos ,Virulência ,Acinetobacter - Abstract
CAPES Acinetobacter spp. é um patógeno essencialmente oportunista e está envolvido em casos de infecções relacionadas à assistência à saúde (IRAS), mais frequentemente em pacientes imunocomprometidos, bem como em pacientes internados em unidades de terapia intensiva, queimados e em tratamento com quimioterapia antineoplásica. Os mais frequentes sítios de infecção são o trato respiratório, principalmente quando associado à ventilação mecânica, trato urinário, corrente sanguínea, feridas e queimaduras. Os mecanismos que conferem resistência a espécies bacterianas de Acinetobacter são diversos e podem ser divididos em três grupos: produção de enzimas capazes de inativar a atividade dos agentes antimicrobianos, alterações ou perda de porinas e aumento da expressão de sistemas ativos de efluxo. Entretanto, os mecanismos de virulência presentes em bactérias do gênero Acinetobacter ainda não são claros. Poucos fatores de virulência foram identificados e caracterizados neste gênero bacteriano, mas sabe-se que os genes envolvidos na biossíntese de pílus, cápsula, sideróforos, fímbrias e biofilme estão presentes em vários isolados clínicos de Acinetobacter, contribuindo para a sua persistência no ambiente hospitalar e no estabelecimento e progressão da infecção. Portanto, este trabalho teve como objetivo pesquisar determinantes genéticos de virulência e resistência em isolado de Acinetobacter nosocomialis sensível, além de determinar o perfil de susceptibilidade aos antimicrobianos, a ocorrência dos sistemas de efluxo e seus reguladores através de sequenciamento genômico dos isolados clínicos de Acinetobacter baumannii multidroga resistentes, provenientes de pacientes internados em um hospital público de referência no tratamento do câncer na cidade de Recife, Pernambuco, durante o ano de 2014. Foram selecionados para o estudo seis isolados de Acinetobacter, sendo um isolado de Acinetobacter nosocomialis sensível aos antimicrobianos e cinco isolados de Acinetobacter baumannii multidroga resistente. Foram determinados os perfis de susceptibilidade ao antimicrobianos pela concentração inibitória mínima (CIM) e realizado o sequenciamento genômico para a pesquisa dos determinantes genéticos de resistência e virulência. Nos cinco isolados multidroga resistentes, os antimicrobianos com maiores taxas de resistência (83,3%) foram ceftriaxona, ceftazidima, imipenem, meropenem e ciprofloxacina seguidos pelo cefepime (66,6%), amicacina e gentamicina (50,0%). Os antimicrobianos mais ativos contra os isolados de A. baumannii testados foram ampicilina/sulbactam, levofloxacina e polimixina B. Em relação aos sistemas de efluxo foram encontrados genes que codificam as bombas das famílias MATE, RND e MFS nos isolados resistentes, além de outros mecanismos de resistência associados como mutações nos genes gyrA e parC (QRDRs), e a presença de enzimas modificadoras de aminoglicosídeos, ambos detectados em nossos isolados. No isolados de A. nosocomialis foram detectados genes que codificam ou contribuem para a formação de alguns dos fatores de virulência que são associados à colonização e estabelecimento do início da infecção a exemplo de genes associados à formação de pilus e biofilme, além dos genes que codificam bombas de efluxo da família RND, cefalosporinase, aminoglicosídeo fosfotranferase e gene de resistência à sulfonamidas. Este estudo ressalta a importância da investigação genética dos determinantes de resistência e virulência em isolados clínicos de Acinetobacter sensíveis ou resistentes que, quando expressos conjuntamente, podem dificultar o tratamento e consequentemente favorecer um mau prognóstico para o paciente. Acinetobacter spp. is an essentially opportunistic pathogen and is involved in cases of health care-related infections (IRAS), most often in immunocompromised patients, as well as in patients admitted to intensive care units, burned and treated with antineoplastic chemotherapy. The most frequent sites of infection are the respiratory tract, especially when associated with mechanical ventilation, urinary tract, bloodstream, wounds and burns. The mechanisms that confer resistance to bacterial species of Acinetobacter are diverse and can be divided into three groups: production of enzymes capable of inactivating the activity of antimicrobial agents, alterations or loss of porins and increased expression of active efflux systems. However, the mechanisms of virulence present in bacteria of the genus Acinetobacter are still unclear. Few virulence factors have been identified and characterized in this bacterial genus, but it is known that genes involved in biosynthesis of pilus, capsule, siderophores, fimbriae and biofilm are present in several clinical isolates of Acinetobacter, contributing to its persistence in the hospital environment and in the establishment and progression of infection. The aim of this study was to investigate genetic determinants of virulence and resistance in susceptible Acinetobacter nosocomialis isolates, as well as to determine the susceptibility profile to antimicrobials, the occurrence of efflux systems and their regulators through genomic sequencing of Acinetobacter baumannii clinical isolates resistant multidrug antibodies from patients admitted to a public referral hospital for cancer treatment in the city of Recife, Pernambuco, during the year 2014. Six isolates of Acinetobacter were selected for the study, being an antimicrobial-sensitive isolate of Acinetobacter nosocomialis and five isolates of Acinetobacter baumannii multidrug resistant. Antimicrobial susceptibility profiles were determined by minimum inhibitory concentration (MIC) and genomic sequencing was performed to investigate the genetic determinants of resistance and virulence. In the five resistant multidrug isolates, the antimicrobials with the highest resistance rates (83.3%) were ceftriaxone, ceftazidime, imipenem, meropenem and ciprofloxacin followed by cefepime (66.6%), amikacin and gentamicin (50.0%). The most active antimicrobials against A. baumannii isolates tested were ampicillin / sulbactam, levofloxacin and polymyxin B. In the efflux systems, genes coding for MATE, RND and MFS families were found in resistant isolates, as well as other mechanisms associated with mutations in the gyrA and parC (QRDRs) genes, and the presence of aminoglycoside modifying enzymes, both detected in our isolates. In the isolates of A. nosocomialis, genes encoding or contributing to the formation of some of the virulence factors associated with colonization and establishment of the onset of infection have been detected, such as genes associated with pilus and biofilm formation, as well as the genes that encode efflux pumps from the RND family, cephalosporinase, aminoglycoside phosphotranferase and sulfonamide resistance gene. This study underscores the importance of genetic investigation of the determinants of resistance and virulence in sensitive or resistant clinical isolates of Acinetobacter that, when expressed together, can make treatment difficult and therefore favor a poor prognosis for the patient.
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- 2017
177. Magnetic, Magnetoelastic and Corrosion Resistant Properties of (Fe–Ni)-Based Metallic Glasses for Structural Health Monitoring Applications.
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Sagasti, Ariane, Palomares, Verónica, Porro, Jose María, Orúe, Iñaki, Sánchez-Ilárduya, M. Belén, Lopes, Ana Catarina, and Gutiérrez, Jon
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STRUCTURAL health monitoring , *IRON alloys , *METALLIC glasses , *GLASS construction , *CORROSION resistance , *CORROSION potential , *MAGNETIC properties - Abstract
We have performed a study of the magnetic, magnetoelastic, and corrosion resistance properties of seven different composition magnetoelastic-resonant platforms. For some applications, such as structural health monitoring, these materials must have not only good magnetomechanical properties, but also a high corrosion resistance. In the fabricated metallic glasses of composition Fe 73 − x Ni x Cr 5 Si 10 B 12 , the Fe/Ni ratio was varied (Fe + Ni = 73% at.) thus changing the magnetic and magnetoelastic properties. A small amount of chromium ( Cr 5) was added in order to achieve the desired good corrosion resistance. As expected, all the studied properties change with the composition of the samples. Alloys containing a higher amount of Ni than Fe do not show magnetic behavior at room temperature, while iron-rich alloys have demonstrated not only good magnetic properties, but also good magnetoelastic ones, with magnetoelastic coupling coefficient as high as 0.41 for x = 0 in the Fe 73 Ni 0 Cr 5 Si 10 B 12 (the sample containing only Fe but not Ni ). Concerning corrosion resistance, we have found a continuous degradation of these properties as the Ni content increases in the composition. Thus, the corrosion potential decreases monotonously from 46.74 mV for the x = 0 , composition Fe 73 Ni 0 Cr 5 Si 10 B 12 to −239.47 mV for the x = 73 , composition Fe 0 Ni 73 Cr 5 Si 10 B 12 . [ABSTRACT FROM AUTHOR]
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- 2020
- Full Text
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178. Análise fenotípica e genética de fatores virulência de isolados clínicos de Pseudomonas aeruginosa multidroga-sensível e multidroga-resistente de Recife - PE
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SILVA, Stephanie Targino, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina Souza
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Virulência ,Virulence ,Pseudomonas aeruginosa ,Resistence ,Resistência - Abstract
CNPq Pseudomonas aeruginosa é um patógeno humano oportunista responsável por causar uma enorme variedade de infecções agudas e crônicas com níveis significativos de morbidade e mortalidade. A sua plasticidade genética e metabólica possibilitou o desenvolvimento de isolados multidroga-resistentes (MDR) e a capacidade de expressar de inúmeros fatores de virulência. Este trabalho teve como objetivo correlacionar o padrão de susceptibilidade antimicrobiana, a produção de fatores de virulência através de técnicas fenotípicas (protease alcalina, hemolisina, fosfolipase C, lipase e pigmentos) e genéticas (genes aprA, lasA, lasB, plcH e toxA) e a variabilidade genética de 30 isolados clínicos de P. aeruginosa isoladas de diferentes sítios de infecção, sendo 15 isolados multidroga-sensível (MDS) e 15 MDR. Nossos resultados revelaram que 50% dos isolados foram resistentes a ceftazidima, sendo as cefalosporinas a classe antimicrobiana com mais isolados resistentes, principalmente entre isolados MDR onde todos foram resistentes. Entre os isolados MDS, todos foram sensíveis a carbapenêmicos e quinolonas. A grande diversidade apresentada no perfil de susceptibilidade às classes de antimicrobianos sugere a existência de associação de diversos mecanismos de resistência. Entre os isolados 53% foram amostras de secreção traqueal, entre estes todos os isolados sensíveis a todos os antimicrobianos testados. Em relação aos fatores de virulência os isolados MDR apresentaram menor produção de piocianina e lipase, e menor detecção dos genes toxA e lasA, enquanto os MDS, apresentaram menor produção de hemolisina e fosfolipase C. Não houve diferença entre os grupos para produção de protease alcalina e o gene aprA. Todos isolados apresentaram produção de piocianina e os genes lasB e plcH. Em relação ao perfil genético, foi encontrada uma grande diversidade, em um total de 30 isolados foi possível observar 28 perfis genéticos. A presença dos clones ocorreu entre os isolados MDR. Embora alguns estudos relatem que o acréscimo de mecanismos de resistência leva a diminuição dos fatores de virulência, sugerindo assim que, as cepas de P. aeruginosa MDR têm a virulência diminuída quando comparada com cepas MDS, neste trabalho dos resultados obtidos não constatamos esta tendência para produção de protease alcalina, hemolisina, fosfolipase C e para a detecção do gene aprA, sugerindo que esta correlação seja multifatorial. Contudo, a ocorrência destes fatores de virulência em quase todos os isolados estudados sugere um elevado nível de patogenicidade dos mesmos. Concluímos portanto, que P. aeruginosa é um patógeno capaz de acumular inúmeros fatores de virulência e frequentemente associado à multirresistência, o que dificulta o tratamento de infecções causadas por esta bactéria. Pseudomonas aeruginosa is an opportunistic human pathogen responsible for causing a wide variety of acute and chronic infections with significant levels of morbidity and mortality. Its genetic and metabolic plasticity enabled the development of multidrug-resistant (MDR) strains and the ability to express countless virulence factors. This paper aimed to correlate the pattern of antimicrobial susceptibility, the production of virulence factors through phenotyping techniques (alkaline protease, hemolysin, phospholipase C, lipase and pigments) and genetic (gene aprA, lasB, lasB, plcH e toxA) and the genetic variability of 30 clinical isolates of P. aeruginosa isolated from different sites of infection, 15 isolates multidrug-sensitive (MDS) and 15 MDR. Our results showed reveal that 50% of the isolates were resistant to ceftazidime, cephalosporin was the antimicrobial class with more resistant isolates, especially isolates MDR that were totally resistant to them. Among the isolated MDS, all were sensitive to carbapenems and quinolones. The large diversity presented in the susceptibility profile to antimicrobial classes suggests the existence of an association of several resistance mechanisms. Among the isolated 53% came from tracheal secretions, among them all isolates susceptible to all antimicrobials tested. Regarding virulence factors MDR isolates presented lower production pyocyanin and lipase, and lower detection toxA e lasA genes, since the MDS, showed lower production of hemolysin and phospholipase C. There was no difference between groups for the production of alkaline protease and aprA gene. All isolates presented pyocyanin production and lasB and plcH genes. In relation to genetic profile, it was verified a large diversity, in a totality of 30 isolates was observed 28 genetic profiles. The presence of clones occurred among the MDR isolates. Even though some studies to report that the increase of resistance mechanisms leads to the reduction of virulence factors, suggesting that the strains of P. aeruginosa MDR have decreased virulence strains compared with MDS, this work the results obtained we have not found this tendency to alkaline protease production, hemolysin, phospholipase C and for detecting aprA gene, suggesting that this correlation is multifactorial. However, the occurrence of these virulence factor in almost all isolates studied suggests a high level of pathogenicity the same. Therefore, it can be concluded that, P. aeruginosa is a pathogen with ability to accumulate several virulence factors and often associated to multiresistant complicating the treatment of infections caused by this bacterium.
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- 2016
179. Caracterização genética de isolados clínicos de Enterobacter aerogenes e Enterobacter cloacae: determinantes de resistência e virulência
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CABRAL, Adriane Borges, LOPES, Ana Catarina de Souza, and CASTRO, Célia Maria Machado Barbosa de
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Virulência ,Enterobacter cloacae ,Enterobacter aerogenes ,Resistência ,Beta-lactamases - Abstract
FACEPE Enterobacter aerogenes e Enterobacter cloacae são importantes patógenos causadores de Infecções relacionadas à Assistência à Saúde (IRAS), podendo apresentar diferentes genes de virulência e de resistência a antimicrobianos. O objetivo desse estudo foi caracterizar e comparar genomicamente isolados de E. aerogenes e E. cloacae multidrogas resistentes (MDR), provenientes de um Hospital público de Recife-PE entre 2011 e 2013, através da investigação de genes relacionados à resistência a antimicrobianos e à virulência, como também analisar o perfil plasmidial e relação clonal dos isolados. Portanto, este estudo foi dividido em três etapas: (1) caracterizar fenotipicamente e genotipicamente 51 isolados de E. aerogenes e E. cloacae provenientes de infecção ou colonização em pacientes de um hospital público de Recife-PE, Brasil, através de perfil de susceptibilidade a antimicrobianos, análises de genes de β-lactamase por PCR e sequenciamento de DNA, perfil plasmidial e ERIC-PCR; (2) realizar o primeiro sequenciamento genômico de 2 isolados de E. aerogenes, blaKPC-2 positivos, provenientes de colonização (Ea5A) e de infecção (Ea7A) em pacientes internados na Unidade de Terapia Intensiva (UTI) de um mesmo hospital, além de análise comparativa com 2 cepas de E. aerogenes sequenciadas anteriormente e (3) realizar sequenciamento genômico de 2 isolados de E. cloacae, blaCTX-M-15 positivos, provenientes de infecções: Ec2A (secreção ocular) e Ec7A (hemocultura) em pacientes internados na Unidade de Terapia Intensiva neonatal (UTI neo) de um mesmo hospital, além de análise comparativa com cepas de E. cloacae sequenciadas anteriormente. Em ambas as espécies houve detecção de altas taxas para ESBL (41%) e carbapenemases (18% para E. cloacae e 88% para E. aerogenes), com identificação das variantes: blaTEM-1, blaCTX-M-15 e blaKPC-2. Os isolados apresentaram disseminação clonal, com E. cloacae blaCTX-M positivo disseminado na UTI neonatal e E. aerogenes blaKPC positivo na UTI e em outros setores do hospital. Foi visto que apesar dos isolados apresentarem relação clonal pela ERIC-PCR apresentaram diferentes perfis plasmidiais e de resistências, além de, diferentes genes de resistência. O sequenciamento genômico permitiu a detecção de: (1) vasto arsenal de genes de resistência a beta-lactâmicos, assim como, genes de resistência a outras classes de antimicrobianos, (2) diversos genes de virulência relacionados a adesinas fimbriais, sideróforos, cápsula e biofilme e (3) cinco tipos de sistemas de efluxo e quatro tipos de sistemas de secreção, relacionados pricipalmente à resistência e virulência, respectivamente. Em relação à análise comparativa dos genomas, foi visto que apesar de serem clones pela ERIC-PCR e provenientes do mesmo setor hospitalar, ambas as espécies apresentaram diferenças sutis no quantitativo de genes totais, genes de resistência, genes de virulência, sistemas de efluxo e secreção, além de características exclusivas de cada isolado. Também foi possível detectar que dentre os isolados de E. aerogenes, foi visto que o isolado proveniente de colonização (Ea5A), apresentou genes de virulência potenciais para estabelecer a infecção, além de elementos genéticos móveis capazes de transmitir diversos genes para outras bactérias presentes na microbiota entérica do paciente, o que reforça a importância da colonização no contexto de IRAS. Considerando os isolados de E. cloacae sequenciados genomicamente, o isolado proveniente de hemocultura (Ec7A) mostrou maior número de determinantes de resistência (beta-lactamases e sistemas de efluxo) que o isolado proveniente de secreção ocular, o que pode dificultar o tratamento e consequentemente favorecer a evolução para estágios mais severos como sepse e choque séptico. Os resultados aqui apresentados evidenciam o vasto arsenal de genes de resistência e virulência albergados pelos isolados de E. aerogenes e E. cloacae o que pode facilitar o estabelecimento da infecção e dificultar o tratamento.
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- 2016
180. Pesquisa de genes de resistência a aminogliosídios em isolados de colonização e infecção de Klebsiella pneumoniae e enterobacter aerogenes portadores do gene blaKPC provinentes de hospitais de Recife-PE
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FIRMO, Elza Ferreira and LOPES, Ana Catarina de Souza
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Klebsiella pneumoniae ,Aminoglicosídeos ,Aminoglycosides ,Enterobacter aerogenes ,biochemical phenomena, metabolism, and nutrition - Abstract
CAPEs Klebsiella pneumoniae e Enterobacter aerogenes têm se destacado como importantes agentes de infecções relacionadas à assistência à saúde (IRAS), causando principalmente infecções de feridas, dos tratos urinário e respiratório, além de sepse. Essas infecções são causadas por linhagens bacterianas geralmente multirresistentes. Genes que codificam as enzimas modificadoras de aminoglicosídeos (EMAs) e metiltransferases 16S RNAr podem estar presentes em isolados de enterobactérias também produtores de Klebsiella pneumoniae carbapapenemase (KPC). Portanto, o objetivo deste estudo foi investigar genes que codificam resistência aos aminoglicosídeos em 30 isolados de E. aerogenes e em 28 isolados de K. pneumoniae portadores do gene blaKPC resistentes a amicacina, tobramicina e/ou gentamicina, oriundos de colonização e infecção em pacientes de diferentes hospitais em Recife-PE, Brasil. A investigação dos genes armA, rmtB, rmtD, aac(3)Ia, aac(3)IIa, aac(6´)Ib, ant(2´)Ia e aph(3’)-VI foi realizada através de PCR, seguida de sequenciamento de DNA. Nos isolados de K. pneumoniae observou-se uma maior ocorrência dos genes ant(2´)Ia, seguidos de aac(3)IIa, aph(3’)-VI e aac(6´)Ib. O gene mais encontrado em E. aerogenes foi o aph(3’)-VI, seguidos de aac(3)-IIa e ant(2”)-Ia. Esse é o primeiro relato de aph(3’)-VI em E. aerogenes no Brasil. Os genes aac(3)-Ia, armA, rmtB e rmtD não foram encontrados. Esses achados ressaltam para a gravidade da alta ocorrência de isolados de K. pneumoniae e E. aerogenes portadores de genes para EMAs e gene blaKPC principalmente colonizando pacientes, visto que essas bactérias podem atuar na disseminação de mecanismos de resistência dentro da unidade hospitalar e limitar as opções de tratamento. Klebsiella pneumoniae and Enterobacter aerogenes have been highlighted as important agents of healthcare-associated infections (HAIs), primarily causing wound, urinary and respiratory tracts infections, and sepsis. These infections are often caused by multiresistant bacterial strains. Genes encoding aminoglycoside modifying enzymes (AMEs) and 16S RNAr methyltransferases can also be present in Enterobacteriaceae isolates producing Klebsiella pneumoniae carbapapenemase (KPC). Therefore, the aim of this study was to investigate genes encoding resistance to aminoglycosides in 30 isolates of E. aerogenes and 28 K. pneumoniae isolates carrying the blaKPC gene and resistant to amikacin, tobramycin and / or gentamicin, from colonization and infection in patients from different hospitals in Recife-PE, Brazil. The investigation of the genes armA, rmtB, rmtD, aac(3)Ia, aac(3)IIa, aac(6´)Ib, ant(2´)Ia e aph(3’)-VI was performed by PCR followed DNA sequencing. In K. pneumoniae isolates there was a higher incidence of genes ant(2´)Ia, followed by aac(3)IIa, aph(3’)-VI e aac(6´)Ib. The gene most frequently found in E. aerogenes was aph(3’)-VI, followed by aac(3)-IIa e ant(2”)-Ia . This is the first report of aph (3 ') - VI in E. aerogenes in Brazil. The genes aac(3)-Ia, armA, rmtB e rmtD were not found. These findings points to the seriousness of the high incidence of isolates of K. pneumoniae and E. aerogenes carriers of AMEs and blaKPC gene, mainly colonizing patients, since these bacteria can act in the dissemination of resistance mechanisms within the hospital and to limit treatment options.
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- 2016
181. Estudo epidemiológico e molecular de infecções ocasionadas por Pseudomonas aeruginosa, Klebsiella spp. E Acinetobacter spp. em pacientes com neoplasias sólidas, internados em um hospital de Recife-PE
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JÁCOME, Paula Regina Luna de Araújo, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina de Souza
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Acinetobacter spp ,Neoplasia ,Klebsiella spp ,Pseudomonas aeruginosa ,cancer ,Beta-Lactamases - Abstract
CAPEs Pseudomonas aeruginosa, Klebsiella spp. e Acinetobacter spp. estão entre as cinco principais causas de infecções relacionadas à assistência à saúde (IRAS), e estão associadas a um elevado índice de mortalidade em pacientes oncológicos. Diante da vulnerabilidade destes pacientes e da crescente incidência de patógenos multidroga resistentes (MDR), o presente trabalho teve por objetivo realiza um estudo epidemiológico e molecular de infecções ocasionadas por P. aeruginosa, Klebsiella spp. e Acinetobacter spp. em pacientes com neoplasias sólidas, internados em um hospital de Recife-PE. Para tal, foi realizado um estudo descritivo de corte transversal dos dados clínicos, microbiológicos e hospitalares e os genes de resistência blaSPM-1, blaIMP, blaVIM, blaKPC, blaTEM e blaCTX-M, foram investigados por meio da reação em cadeia da polimerase. Também foi realizada tipagem molecular dos isolados MDR utilizando a técnica Enterobacterial Repetitive Intergenic Consensus-based PCR (ERIC-PCR). Entre 2012 e 2014, foram obtidos 169 isolados, sendo 58 P. aeruginosa, 36 Acinetobacter spp. e 75 Klebsiella spp.. A frequência de patógenos MDR (69,6%, IC95% 61,5% - 76,9%) foi significativamente maior que os isolados não MDR (30,4%, IC95% 23,1% - 38,5%). Dentre as bactérias resistentes aos carbapenêmicos, o gene blaSPM-1 foi detectado em P. aeruginosa (35,5%) e Acinetobacter spp. (3,8%), e o gene blaKPC detectado apenas em P. aeruginosa (25,8%). Já entre os isolados resistentes às cefalosporinas de terceira e quarta geração, o gene blaTEM estava presente em Acinetobacter spp. (25,9%) e Klebsiella spp. (30,6%) e o gene blaCTX-M em 58,3% das Klebsiella spp.. Também foi observado que o câncer de pulmão e os pacientes do sexo masculino foram predominantes na amostra e que o uso prévio de antimicrobianos durante o internamento e até três meses antes do isolamento do patógeno descrito neste estudo, apresentaram associação com o desenvolvimento de infecções por patógenos MDR. Assim, os resultados encontrados podem contribuir com epidemiologia molecular dos genes de resistência presentes no ambiente hospitalar, além de ressaltar a importância da monitorização contínua das IRAS em pacientes com câncer internados por longos períodos, a fim de melhorar os cuidados prestados a estes pacientes. Pseudomonas aeruginosa, Klebsiella spp. and Acinetobacter spp. are among the five leading causes of Healthcare-associated Infections (HAI) in cancer patients, and those associated with a high mortality rate. Because of the vulnerability of patients and the increasing incidence of multidrug-resistant pathogens (MDR), this study aimed to realize an epidemiological and molecular study of infections caused by P. aeruginosa, Klebsiella spp. and Acinetobacter spp. in patients with solid tumors, admitted to a Recife-PE hospital. Therefore, we conducted a descriptive cross-sectional study of clinical, microbiological and hospital, and the resistance genes blaSPM-1, blaIMP, blaVIM, blaKPC, blaTEM and blaCTX-M, were investigated by polymerase chain reaction. It was also performed molecular typing of MDR isolates using Enterobacterial Repetitive Intergenic Consensus-based PCR (ERIC-PCR). Between 2012 and 2014, were obtained 169 isolates, 58 P. aeruginosa, 36 Acinetobacter spp. and 75 Klebsiella spp.. The frequency of MDR pathogens (69.6% 95% 61.5% - 76.9%) was significantly higher than non-MDR isolates (30.4% 95% 23.1% - 38.5%). Among the carbapenem-resistant bacteria, the blaSPM-1 gene was detected in P. aeruginosa (35.5%) and Acinetobacter spp. (3.8%), and blaKPC gene detected only in P. aeruginosa (25.8%). Among the resistant isolates to the third and fourth generation cephalosporins, the blaTEM gene was present in Acinetobacter spp. (25.9%) and Klebsiella spp. (30.6%) and blaCTX-M gene in 58.3% of the Klebsiella spp.. It was also noted that lung cancer and male patients were predominant in the sample and the previous use of antimicrobials during hospitalization and antibiotic use up to three months before the pathogen isolation described in this study were associated with the development of pathogen infections MDR. Thus, the results can contribute to molecular epidemiology of resistance genes present in the hospital, and underline the importance of continuous monitoring of HAI in cancer patients hospitalized for long periods aiming improve the care provided to these patients.
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- 2015
182. DETECÇÃO MOLECULAR DE BETA-LACTAMASES DE ESPECTRO ESTENDIDO EM ISOLADOS CLÍNICOS DE Pseudomonas aeruginosa PROVENIENTES DE HOSPITAL PÚBLICO DE PERNAMBUCO
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SILVA JÚNIOR, Valdemir Vicente da, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina de Souza
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Pseudomonas aeruginosa ,Farmacorresistência bacteriana ,Beta-Lactamases - Abstract
Pseudomonas aeruginosa é uma bactéria gram-negativa conhecida por causar infecções oportunistas em diversos sítios do corpo humano principalmente tendo como destaque as infecções das vias aéreas. Estes patógenos apresentam resistência intrínseca a várias classes de agentes antimicrobianos, e notável habilidade em adquirir outros mecanismos de resistência, como por exemplo, a ação de enzimas beta-lactamases. Os genes que codificam essas enzimas geralmente são adquiridos através de mecanismos de transferência genética intra e/ou interespécies. A ação dessas beta-lactamases juntamente com outros mecanismos de resistência é frequentemente a razão das falhas terapêuticas durante o tratamento das infecções. Sendo assim, o presente estudo visou determinar a frequência genotípica de beta-lactamases do tipo ESBL (Beta-lactamases de espectro estendido) em isolados de P.aeruginosa provenientes do Hospital das Clínicas de Pernambuco (HC-UFPE). Os 159 isolados tiveram seu DNA extraído através do kit Brazol. O DNA obtido da extração foi quantificado e diluído para então iniciar a pesquisa genética através da técnica de PCR. Os isolados foram selecionados para pesquisa molecular de acordo com o perfil de resistência. Para o gene blaTEM, 1,41% (1/71) apresentou positividade; com relação ao blaGES observou-se que 2 isolados dos 54 testados (3,92%) carreavam o gene, após sequenciamento e análise in silico verificou-se que se tratava da GES-1; a tipagem molecular por ERIC-PCR demonstrou que os dois isolados são geneticamente relacionados. Esses achados possuem importância epidemiológica molecular dado que o gene blaGES em P.aeruginosa ainda não foi descrito no nordeste Brasileiro e o gene blaTEM em P.aeruginosa não foi relatado no Brasil; e portanto, servem de alerta para uma possível disseminação desses genes que contribuem de forma expressiva na resistência apresentada por isolados de P.aeruginosa.
- Published
- 2014
183. Caracterização fenotípica e molecular da resistência aos macrolídeos, lincosamidas e estreptograminas B de isolados clínicos de Staphylococcus spp
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PEREIRA, Jussyêgles Niedja da Paz, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina de Souza
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Clindamicina ,Genes ,Staphylococcus ,Eritromicina ,Meticilina - Abstract
Os Staphylococcus spp. demonstraram, ao longo do tempo, a notável capacidade de desenvolver resistência a maioria dos antimicrobianos. Há um mecanismo de resistência aos macrolídeos, em Staphylococcus spp. que atinge também as lincosamidas e as estreptograminas B caracterizando a denominada resistência MLSB, cuja expressão pode ser constitutiva (MLSBc) ou induzível (MLSBi) e é codificada principalmente pelos genes ermA e ermC. A resistência MLSBc é facilmente detectada pelos testes de susceptibilidade utilizados na rotina laboratorial, mas a resistência MLSBi não é. A terapia com clindamicina nos casos de infecção por isolados com resistência MLSBi pode falhar. O objetivo deste estudo foi caracterizar o perfil fenotípico (ocorrência dos fenótipos MLSBc e MLSBi) e molecular (ocorrência dos genes ermA e ermC) da resistência MLSB dos isolados clínicos de Staphylococcus aureus e SCN (Staphylococcus coagulase negativos) sensíveis e resistentes à meticilina provenientes de pacientes do Hospital das Clínicas da Universidade Federal de Pernambuco (HC-UFPE), durante o ano de 2012. A susceptibilidade antimicrobiana de 103 isolados foi determinada pela técnica de disco difusão em ágar Mueller-Hinton. Posteriormente, foi realizado o screening de oxacilina. O fenótipo MLSBi foi detectado através do teste D. Foram submetidos a reação em cadeia da polimerase (PCR), 13 isolados com fenótipos MLSBc e MLSBi para a detecção dos genes ermA e ermC. Os fenótipos MLSBc e MLSBi foram identificados respectivamente em 39 (37,9%) e cinco (4,9%) isolados. O fenótipo MLSBi foi encontrado apenas em quatro (10,8%) dos S. aureus sensíveis à meticilina e em um (4,5%) dos S. aureus resistentes a meticilina. Dos 13 isolados submetidos a PCR, seis (46,2%) apresentaram um gene erm. Foi verificada a mesma frequência três (23,1%) dos genes ermA e ermC entre os isolados. Os genes ermA e ermC se fizeram presentes entre alguns dos isolados de Staphylococcus spp. do hospital estudado e apesar do fenótipo MLSBi ter sido menos frequente que o MLSBc, é importante a realização do teste D para detectá-lo e assim, orientar condutas terapêuticas.
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- 2014
184. Isolados clínicos de Klebsiella pneumoniae produtores e não produtores de KPC: relação com a presença dos genes de virulência fimH, mrkD e irp2
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MELO, Rita de Cássia Andrade, LOPES, Ana Catarina de Souza, and MACIEL, Maria Amélia Vieira
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Klebsiella pneumoniae ,Virulência ,Resistência - Abstract
Klebsiella pneumoniae é um patógeno oportunista frequentemente associado a infecções hospitalares do trato respiratório e do trato urinário de indivíduos imunocomprometidos e neonatos, e podem produzir diferentes tipos de fatores de virulência, como adesinas fimbriais (genes fimH e mrkD ) e sideróforos, como a yersiniabactina (gene irp2), importantes no desenvolvimento da infecção. O objetivo do presente estudo foi determinar a ocorrência dos genes de virulência fimH, mrkD e irp2 em isolados de K. pneumoniae produtores e não produtores de KPC, provenientes de pacientes de diferentes hospitais de Recife-PE, como também a relação clonal, através da ERIC-PCR, e o perfil de susceptibilidade a antimicrobianos desses isolados bacterianos. Para esse estudo foram selecionados 23 isolados produtores de KPC e 23 isolados não produtores de KPC, todos da espécie K. pneumoniae. Os genes de virulência foram detectados através da PCR e sequenciamento de DNA. Analisando o perfil de susceptibilidade aos antimicrobianos dos isolados selecionados, observamos que a amicacina (n=39/ 84,78%) e a polimixina (n=41/ 89,13%), foram os antimicrobianos de melhor atividade para inibir a K. pneumoniae, tanto KPC-positivas quanto negativas, onde observamos que 5 isolados apresentaram resistência a polimixina, sendo 3 no grupo KPC-positivo e 2 no grupo KPC-negativo. Esse é o primeiro relato da resistência de K. pneumoniae à polimixina. No grupo KPC-positivo foi observada uma alta taxa de resistência à cefalosporinas, seguidas dos carbapenêmicos. Ficou evidenciado que o ertapenem é o melhor antimicrobiano para detectar resistência fenotípica ao grupo dos carbapenêmicos. A tipagem pela ERIC-PCR gerou 37 perfis genéticos, demonstrando que houve Uma disseminação multiclonal de isolados de K. pneumoniae em Recife-PE, Brasil. Dentre os 46 isolados analisados pela ERIC-PCR, cincoperfis agruparam mais de um isolado bacteriano com relação clonal. No presente estudo não foi possível detectar a relação direta entre a presença do gene blaKPC com cada gene de virulência individualmente, visto que os grupos estudados, KPC-positivo e KPC-negativo, apresentaram presenças semelhantes dos genes de virulência. Por outro lado, foi observado que os genes de virulência irp2, mrkD e fimH apresentaram-se juntos com uma maior frequência no grupo KPC-positivo. O acúmulo de genes de virulência em isolados de K. pneumoniae KPC positivos, observado nesse estudo, juntamente com a multirresistência, impõe relevantes limitações terapêuticas no tratamento de infecções causadas por K. pneumoniae em Recife-PE, Brasil.
- Published
- 2013
185. Caracterização genética da resistência antimicrobiana em isolados clínicos de Pseudomonas aeruginosa provenientes de um Hospital Universitário em Recife, Pernambuco
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ALVES, Lilian Rodrigues, MACIEL, Maria Amélia Vieira, and LOPES, Ana Catarina de Souza
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Pseudomonas aeruginosa ,Resistência bacteriana a antibióticos ,Tipagem molecular ,Infecção - Abstract
Propesq-UFPE, CNPq e CAPES Pseudomonas aeruginosa é um patógeno oportunista associado a infecções relacionadas à assistência a saúde (IRAS), cuja principal característica é a capacidade de desenvolver resistência a diversos antimicrobianos através da produção de enzimas metalo-β-lactamases (MβLs) e KPC (Klebsiella pneumoniae-carbapenemase), além da hiperexpressão dos sistemas de efluxo multidroga. O objetivo do estudo foi caracterizar o perfil de fenotípico e genético de resistência, bem como determinar o grau de similaridade genética de isolados clínicos de P. aeruginosa provenientes de um hospital universitário em Recife, Pernambuco, no período de abril a agosto de 2011 e maio a setembro de 2012. O perfil de susceptibilidade dos isolados de P. aeruginosa foi determinado pela técnica de disco-difusão, segundo critérios do Clinical and Laboratory Standards Institute (CLSI, 2012). A pesquisa dos genes mexA, mexE e mexX foi realizada em isolados multidroga resistentes (MDR) e a pesquisa dos genes blaSPM, blaIMP, blaVIM e blaKPC foi realizada em isolados que apresentaram resistência a cefalosporinas e carbapenêmicos. Os genes descritos foram detectados pela Reação em Cadeia da Polimerase. Todos os isolados foram submetidos à tipagem molecular através da técnica de amplificação de sequências de consenso intergênicas repetitivas de enterobactérias (ERIC-PCR). Cento e vinte isolados de P. aeruginosa apresentaram taxas de resistência variando de 7,5% para polimixina e 52,5% para cefotaxima. Não foram observados genes MβL nos 17 isolados resistentes a ceftazidima e imipenem ou meropenem. O gene blaKPC foi encontrado em 4/33 isolados resistentes aos carbapenêmicos. Os genes mexA e mexE foram detectados em 67/69 isolados MDR e o mexX em 66/69. A ERIC-PCR demonstrou 82 perfis genéticos distintos entre os 120 isolados. Neste estudo, concluiu-se que os sistemas de efluxo e a KPC parecem contribuir para a resistência de isolados de P. aeruginosa. A heterogeneidade genética observada pode estar relacionada com a variabilidade genética desta espécie bacteriana oriunda de mutações não letais e recombinações, como a conjugação e transformação.
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- 2013
186. Self-healing, piezoresistive and temperature responsive behaviour of chitosan/polyacrylic acid dynamic hydrogels.
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Conejo-Cuevas G, Lopes AC, Badillo I, Del Campo FJ, Ruiz-Rubio L, and Pérez-Álvarez L
- Abstract
Flexible electronics have introduced new challenges for efficient human-machine interactions. Hydrogels have emerged as prominent materials for electronic wearable applications due to their exceptional mechanical deformability and lightweight characteristics combined in some cases with conductive properties, and softness. Additionally, bio-interphases require multisensory response to stress, strain, temperature, and self-healing capacity. To mimic these properties, this work developed interpenetrated hydrogel networks composed of chitosan (CHI) and polyacrylic acid (PAA), combined with Fe (III) ions and varying amounts of NMBA (0-0.25 %), to achieve tailored conductivity (0.8-2.5 mS/cm), self-healing, self-standing and mechanical properties (E = 11.7-110 Pa and fracture strain = 64.9-1923 %) suitable for strain sensor applications. The results revealed a significant influence of the restrictive effect on the mobility of uncrosslinked chain segments, caused by Fe ions and NMBA, on the piezoresistance (GF 2.1-1.3) and self-healing capability of the gels. Interestingly, a transparent/turbid transition, driven by microphase separation that is characteristic of systems with high dynamic interactions, was encountered for the first time in these hydrogels. This transition was analyzed in relation to external temperature, water content, pH, and the influence of Fe ions and NMBA. The simultaneous sensitivity of these materials to temperature and pH, along with their piezoresistive and self-healing behaviour, can be highly valuable for multifunctional sensors in a wide range of applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
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- 2025
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187. Occurrence of blaNDM-1, blaNDM-5, blaNDM-7, and blaKPC-2 genes in clinical isolates of enterobacterales with high genetic variability, from colonization and infection in patients with or without COVID-19, from a hospital in Brazil.
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Martins LR, Pimentel MIS, de Oliveira ÉM, Jucá MB, Beltrão EMB, and Lopes ACS
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- Humans, Brazil, Genetic Variation, Anti-Bacterial Agents pharmacology, Microbial Sensitivity Tests, Enterobacteriaceae genetics, Enterobacteriaceae drug effects, Enterobacteriaceae isolation & purification, Carbapenems pharmacology, Hospitals, Klebsiella pneumoniae genetics, Klebsiella pneumoniae isolation & purification, Klebsiella pneumoniae drug effects, COVID-19 microbiology, beta-Lactamases genetics, SARS-CoV-2 genetics, Enterobacteriaceae Infections microbiology
- Abstract
Aims: This study aimed to investigate the presence of beta-lactams resistance genes and the clonal relationship of clinical isolates of Enterobacterales obtained from patients with and without COVID-19, in a hospital in northeastern Brazil., Methods and Results: The study analyzed 45 carbapenem-resistant clinical isolates using enterobacterial repetitive intergenic consensus (ERIC-PCR), PCR, and amplicon sequencing to detect resistance genes (blaKPC, blaGES, blaNDM, blaVIM, and blaIMP). The main species were Klebsiella pneumoniae, Serratia marcescens, and Proteus mirabilis. Detected genes included blaNDM (46.66%), blaKPC (35.55%), and both (17.79%). ERIC-PCR showed multiclonal dissemination and high genetic variability. The main resistance gene was blaNDM, including blaNDM-5 and blaNDM-7., Conclusions: The presence of Enterobacterales carrying blaKPC and blaNDM in this study, particularly K. pneumoniae, in infections and colonizations of patients with COVID-19 and non-COVID-19, highlights genetic variability and resistance to carbapenems observed in multiple species of this order., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)
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- 2024
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188. Genetic profile and characterization of antimicrobial resistance in Acinetobacter baumannii post-COVID-19 pandemic: a study in a tertiary hospital in Recife, Brazil.
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Rocha IV, Martins LR, Pimentel MIS, Mendes RPG, and Lopes ACS
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- Brazil, Humans, Drug Resistance, Multiple, Bacterial genetics, Bacterial Proteins genetics, Male, Adult, Female, Middle Aged, Drug Resistance, Bacterial genetics, Acinetobacter baumannii genetics, Acinetobacter baumannii drug effects, Acinetobacter baumannii isolation & purification, Tertiary Care Centers, Acinetobacter Infections microbiology, Acinetobacter Infections drug therapy, Acinetobacter Infections epidemiology, beta-Lactamases genetics, COVID-19, Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Microbial Sensitivity Tests, SARS-CoV-2 genetics
- Abstract
Aims: To investigate the genetic profile and characterize antimicrobial resistance, including the main β-lactam antibiotic resistance genes, in Acinetobacterbaumannii isolates from a tertiary hospital in Recife-PE, Brazil, in the post-COVID-19 pandemic period., Methods and Results: Acinetobacter baumannii isolates were collected between 2023 and 2024 from diverse clinical samples. Antimicrobial resistance testing followed standardized protocols, with β-lactamase-encoding genes detected via PCR and sequencing. Investigation into ISAba1 upstream of blaOXA-carbapenemase and blaADC genes was also conducted. Genetic diversity was assessed through ERIC-PCR. Among the 78 A. baumannii, widespread resistance to multiple antimicrobials was evident. Various acquired β-lactamase-encoding genes (blaOXA-23,-24,-58,-143, blaVIM, and blaNDM) were detected. Furthermore, this is the first report of blaVIM-2 in A. baumannii isolates harboring either the blaOXA-23-like or the blaOXA-143 gene in Brazil. Molecular typing revealed a high genetic heterogeneity among the isolates, and multi-clonal dissemination., Conclusion: The accumulation of genetic resistance determinants underscores the necessity for stringent infection control measures and robust antimicrobial stewardship programs to curb multidrug-resistant strains., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)
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- 2024
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189. Virulent Klebsiella pneumoniae ST11 clone carrying blaKPC and blaNDM from patients with and without COVID-19 in Brazil.
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Pimentel MIS, Beltrão EMB, de Oliveira ÉM, Martins LR, Jucá MB, and Lopes ACS
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- Brazil, Humans, Virulence genetics, Anti-Bacterial Agents pharmacology, Multilocus Sequence Typing, Microbial Sensitivity Tests, Virulence Factors genetics, Klebsiella pneumoniae genetics, Klebsiella pneumoniae isolation & purification, Klebsiella pneumoniae pathogenicity, Klebsiella Infections microbiology, COVID-19 microbiology, beta-Lactamases genetics, SARS-CoV-2 genetics
- Abstract
Aims: Investigated and compared the occurrence of virulence genes fimH, mrkD, irp2, entB, cps, rmpA, and wabG, resistance genes blaKPC and blaNDM, and the genetic variability and clonal relationship of 29 Klebsiella pneumoniae clinical isolates of patients with and without COVID-19, from a hospital in Brazil., Methods and Results: All isolates were resistant to beta-lactams. The genes were investigated by PCR, and for molecular typing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and MLST were used. The detection of blaNDM was greater (n = 23) when compared to that of blaKPC (n = 14). The virulence genes that most occurred were fimH, entB, cps, and wabG, which are responsible for adhesins, siderophore enterobactin, capsule, and lipopolysaccharides, respectively. Among the isolates, 21 distinct genetic profiles were found by ERIC-PCR, with multiclonal dissemination. Four isolates belonged to the ST11 clone., Conclusions: The occurrence of the ST11 is worrying as it is a high-risk clone involved in the dissemination of virulent strains throughout the world., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)
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- 2024
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190. Ceftazidime/Tobramycin Co-Loaded Chitosan-Coated Zein Nanoparticles against Antibiotic-Resistant and Biofilm-Producing Pseudomonas aeruginosa and Klebsiella pneumoniae .
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Campos LAA, Neto AFS, Scavuzzi AML, Lopes ACS, Santos-Magalhães NS, and Cavalcanti IMF
- Abstract
This study aimed to co-encapsulate ceftazidime and tobramycin in zein nanoparticles coated with chitosan and to characterize and evaluate the antibacterial and antibiofilm activity against antibiotic-resistant Pseudomonas aeruginosa and Klebsiella pneumoniae . Zein nanoparticles, synthesized using the nanoprecipitation method, were characterized by their particle size (Ø), polydispersity index (PDI), zeta potential (ζ), pH, and encapsulation efficiency (%EE). The chitosan coating provided stability, and physicochemical analyses revealed chemical interactions, efficient drug encapsulation, and thermal stability. The release kinetics demonstrated controlled release in simulated gastric and intestinal pH. The antibacterial activity, assessed by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), indicated effectiveness against both pathogens. Antibiofilm assays, conducted using the crystal violet method, demonstrated the inhibition and eradication of biofilms. The chitosan-coated zein nanoparticles with CAZ and/or TOB exhibited Ø (315-335 nm), PDI (<0.2), ζ (+40 to +50 mV), pH (5), and %EE (>55%). Notably, the co-encapsulation formulation (CAZ-TOB-ZNP-CH) showed enhanced antibacterial and antibiofilm activities compared to the individual formulations. These findings suggest that the developed nanoparticles present a promising alternative for treating respiratory and intestinal infections caused by antibiotic-resistant and biofilm-producing P. aeruginosa and K. pneumoniae .
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- 2024
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191. Olive oil nanoemulsion containing curcumin: antimicrobial agent against multidrug-resistant bacteria.
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Confessor MVA, Agreles MAA, Campos LAA, Silva Neto AF, Borges JC, Martins RM, Scavuzzi AML, Lopes ACS, Kretzschmar EAM, and Cavalcanti IMF
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- Anti-Bacterial Agents pharmacology, Ceftazidime pharmacology, Olive Oil pharmacology, Gram-Positive Bacteria, Gram-Negative Bacteria, Klebsiella pneumoniae, Microbial Sensitivity Tests, Curcumin pharmacology, Curcumin chemistry, Anti-Infective Agents pharmacology
- Abstract
The present work aimed to develop, characterize, and evaluate the antibacterial and antibiofilm activity of two nanoemulsions (NEs) containing 500 µg/mL of curcumin from Curcuma longa (CUR). These NEs, produced with heating, contain olive oil (5%) and the surfactants tween 80 (5%) and span 80 (2.5%), water q.s. 100 mL, and were stable for 120 days. NE-2-CUR presented Ø of 165.40 ± 2.56 nm, PDI of 0.254, ζ of - 33.20 ± 1.35 mV, pH of 6.49, and Entrapment Drug Efficiency (EE) of 99%. The NE-4-CUR showed a Ø of 105.70 ± 4.13 nm, PDI of 0.459, ζ of - 32.10 ± 1.45 mV, pH of 6.40 and EE of 99.29%. Structural characterization was performed using DRX and FTIR, thermal characterization using DSC and TG, and morphological characterization using SEM, suggesting that there is no significant change in the CUR present in the NEs and that they remain stable. The MIC was performed by the broth microdilution method for nine gram-positive and gram-negative bacteria, as well as Klebsiella pneumoniae clinical isolates resistant to antibiotics and biofilm and efflux pump producers. The NEs mostly showed a bacteriostatic profile. The MIC varied between 125 and 250 µg/mL. The most sensitive bacteria were Staphylococcus aureus and Enterococcus faecalis, for which NE-2-CUR showed a MIC of 125 µg/mL. The NEs and ceftazidime (CAZ) interaction was also evaluated against the K. pneumoniae resistant clinical isolates using the Checkerboard method. NE-2-CUR and NE-4-CUR showed a synergistic or additive profile; there was a reduction in CAZ MICs between 256 times (K26-A2) and 2 times (K29-A2). Furthermore, the NEs inhibited these isolates biofilms formation. The NEs showed a MBIC ranging from 15.625 to 250 µg/mL. Thus, the NEs showed physicochemical characteristics suitable for future clinical trials, enhancing the CAZ antibacterial and antibiofilm activity, thus becoming a promising strategy for the treatment of bacterial infections caused by multidrug-resistant K. pneumoniae. KEY POINTS: • The NEs showed physicochemical characteristics suitable for future clinical trials. • The NEs showed a synergistic/additive profile, when associated with ceftazidime. • The NEs inhibited biofilm formation of clinical isolates., (© 2024. The Author(s).)
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- 2024
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192. Antinociceptive and anti-inflammatory activities of essential oil of the leaves of Amburana cearensis (Allemão) A.C. Smith. from the semi-arid region of Northeastern Brazil.
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de Veras BO, Moura GMM, Barros AV, Vanusa da Silva M, Assis PAC, Aguiar JCROF, Navarro DMDAF, Ximenes RM, Wanderley AG, Oliveira MBM, and Lopes ACS
- Subjects
- Mice, Animals, Carrageenan, Brazil, Anti-Inflammatory Agents therapeutic use, Anti-Inflammatory Agents toxicity, Analgesics therapeutic use, Analgesics toxicity, Pain drug therapy, Pain chemically induced, Plant Extracts therapeutic use, Plant Extracts toxicity, Inflammation drug therapy, Plant Leaves chemistry, Edema chemically induced, Edema drug therapy, Oils, Volatile therapeutic use, Oils, Volatile toxicity, Fabaceae, Peritonitis drug therapy
- Abstract
Ethnopharmacological Relevance: Amburana cearensis (Allemão) A.C. Smith is a medicinal plant with wide distribution in South America, popularly known in Brazil as "cumaru" or "amburana de cheiro". In folk medicine, in the semi-arid region of Northeastern Brazil, infusions, teas and decoctions of leaves of Amburana cearensis have their practical use for treating fever, gastrointestinal disorders, inflammation, and inflammation pain. However, none of the ethnopharmacological properties has been scientifically evaluated using volatile compounds obtained from its leaves (essential oil)., Aim of the Study: This study investigated the chemical composition, acute oral toxicity, and antinociceptive and anti-inflammatory activities of the essential oil from the leaves of A. cearensis., Material and Methods: The acute toxicity of the essential oil was investigated in mice. The antinociceptive effect was evaluated using the formalin test and, abdominal writhing induced by acetic acid, being investigated the possible mechanisms of action involved in antinociception. The acute anti-inflammatory effect was investigated through models of carrageenan-induced peritonitis, yeast-induced pyrexia, and carrageenan- and histamine-induced paw inflammation., Results: No acute toxicity was observed at doses up to 2000 mg/kg; p.o. The antinociceptive effect was statistically equal to morphine. In the formalin assay, the oil showed analgesic activity in the neurogenic and inflammatory phases, having as mechanisms the cholinergic, adenosinergic system, and ATP-sensitive potassium channels (K-ATP). In peritonitis, a reduction in TNF-α and IL-1β levels and leukocyte migration were observed. The antipyretic effect was statistically superior to dipyrone. The reduction in paw edema was statistically superior to the standard in both models., Conclusion: The results obtained not only support the traditional use of the species in inflammatory conditions and pain in folk medicine but also demonstrate that this is a rich source of phytocomponents such as germacrone, which can be used as a natural and sustainable therapeutic agent with industrial applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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193. Occurrence of high-risk clones of Klebsiella pneumoniae ST11, ST340, and ST855 carrying the blaKPC-2, blaNDM-1, blaNDM-5, and blaNDM-7 genes from colonized and infected patients in Brazil.
- Author
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de Oliveira ÉM, Beltrão EMB, Pimentel MIS, and Lopes ACS
- Subjects
- Humans, Multilocus Sequence Typing, Brazil epidemiology, Clone Cells, Microbial Sensitivity Tests, Anti-Bacterial Agents pharmacology, Klebsiella pneumoniae genetics, beta-Lactamases genetics
- Abstract
Aims: Determine which sequence type (ST) clones were carrying the blaKPC, blaNDM, blaVIM, blaIMP, and blaGES genes and their variants in clinical isolates of multidrug-resistant Klebsiella pneumoniae., Methods and Results: Ten K. pneumoniae isolates were obtained from the colonized and infected patients in a public hospital in the city of Recife-PE, in northeastern Brazil, and were further analyzed. The detection of carbapenem resistance genes and the seven housekeeping genes [for multilocus sequence typing (MLST) detection] were done with PCR and sequencing. The blaKPC and blaNDM genes were detected concomitantly in all isolates, with variants being detected blaNDM-1, blaNDM-5, blaNDM-7, and blaKPC-2. The blaKPC-2 and blaNDM-1 combination being the most frequent. Molecular typing by MLST detected three types of high-risk ST clones, associated with the clonal complex 258, ST11/CC258 in eight isolates, and ST855/CC258 and ST340/CC258 in the other two isolates., Conclusions: These findings are worrying, as they have a negative impact on the scenario of antimicrobial resistance, and show the high genetic variability of K. pneumoniae and its ability to mutate resistance genes and risk of dissemination via different ST clones., (© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.)
- Published
- 2023
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194. Ocular Symptoms Associated with COVID-19 Are Correlated with the Expression Profile of Mouse SARS-CoV-2 Binding Sites.
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Brechbühl J, Ferreira F, Lopes AC, Corset E, Gilliand N, and Broillet MC
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- Humans, Animals, Mice, SARS-CoV-2, Angiotensin-Converting Enzyme 2 genetics, Pandemics, Binding Sites, COVID-19, Lacrimal Apparatus
- Abstract
The COVID-19 pandemic has engendered significant scientific efforts in the understanding of its infectious agent SARS-CoV-2 and of its associated symptoms. A peculiar characteristic of this virus lies in its ability to challenge our senses, as its infection can lead to anosmia and ageusia. While ocular symptoms, such as conjunctivitis, optic neuritis or dry eyes, are also reported after viral infection, they have lower frequencies and severities, and their functional development is still elusive. Here, using combined technical approaches based on histological and gene profiling methods, we characterized the expression of SARS-CoV-2 binding sites ( Ace2/Tmprss2 ) in the mouse eye. We found that ACE2 was ectopically expressed in subtissular ocular regions, such as in the optic nerve and in the Harderian/intraorbital lacrimal glands. Moreover, we observed an important variation of Ace2 / Tmprss2 expression that is not only dependent on the age and sex of the animal, but also highly heterogenous between individuals. Our results thus give new insight into the expression of SARS-CoV-2 binding sites in the mouse eye and propose an interpretation of the human ocular-associated symptoms linked to SARS-CoV-2.
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- 2023
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195. Food preference acquired by social transmission is altered by the absence of the olfactory marker protein in mice.
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de Vallière A, Lopes AC, Addorisio A, Gilliand N, Nenniger Tosato M, Wood D, Brechbühl J, and Broillet MC
- Abstract
Food preference is conserved from the most primitive organisms to social animals including humans. A continuous integration of olfactory cues present both in food and in the different environmental and physiological contexts favors the intake of a given source of food or its avoidance. Remarkably, in mice, food preference can also be acquired by olfactory communication in-between conspecifics, a behavior known as the social transmission of food preference (STFP). STFP occurs when a mouse sniffs the breath of a conspecific who has previously eaten a novel food emitting specific odorants and will then develop a preference for this never encountered food. The efficient discrimination of odorants is performed by olfactory sensory neurons (OSNs). It is essential and supports many of the decision-making processes. Here, we found that the olfactory marker protein (OMP), an enigmatic protein ubiquitously expressed in all mature olfactory neurons, is involved in the fine regulation of OSNs basal activity that directly impacts the odorant discrimination ability. Using a previously described Omp null mouse model, we noticed that although odorants and their hedonic-associated values were still perceived by these mice, compensatory behaviors such as a higher number of sniffing events were displayed both in the discrimination of complex odorant signatures and in social-related contexts. As a consequence, we found that the ability to differentiate the olfactory messages carried by individuals such as those implicated in the social transmission of food preference were significantly compromised in Omp null mice. Thus, our results not only give new insights into the role of OMP in the fine discrimination of odorants but also reinforce the fundamental implication of a functional olfactory system for food decision-making., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 de Vallière, Lopes, Addorisio, Gilliand, Nenniger Tosato, Wood, Brechbühl and Broillet.)
- Published
- 2022
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196. Electro and magnetoactive printed bi-functional actuators based on alginate hybrid hydrogels.
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Maiz-Fernández S, Pérez-Álvarez L, de Munain-Arroniz IL, Zoco A, Lopes AC, Silván U, Salazar D, Vilas-Vilela JL, and Lanceros-Mendez S
- Subjects
- Alginates chemistry, Iron, Hydrogels chemistry, Nanoparticles
- Abstract
Soft materials are attracting much attention for the development of biostructures able to mimic the movement of natural systems by remote actuation. Multi-sensitive hydrogels are among the best materials for obtaining dynamic and biocompatible soft structures for soft actuators and related biomedical devices. Nevertheless, bioinks based on naturally occurring and stimuli responsive hydrogels able to be 3D printed continues being a challenge for advanced applications. In this work 3D printable electrically and magnetically responsive, non-cytotoxic, hybrid hydrogels based on alginate and zero monovalent iron nanoparticles (NPs) are presented. The effect of NPs addition on the physico-chemical properties of the hydrogels is addressed, together with its effect on the functional electroactive and magnetoactive response. NPs concentration up to 10 % do not affect the mechanical stability of the gels, while promoting an increase actuation response., Competing Interests: Declaration of competing interest None., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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197. Occurrence of bla NDM-7 and association with bla KPC-2 , bla CTX-M15 , aac, aph, mph(A), catB3 and virulence genes in a clinical isolate of Klebsiella pneumoniae with different plasmids in Brazil.
- Author
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de Oliveira Alves W, Scavuzzi AML, Beltrão EMB, de Oliveira ÉM, Dos Santos Vasconcelos CR, Rezende AM, and de Souza Lopes AC
- Subjects
- Brazil, Drug Resistance, Multiple, Bacterial genetics, Galanin analogs & derivatives, Humans, Plasmids genetics, Sequence Analysis, DNA, Substance P analogs & derivatives, Virulence genetics, beta-Lactamases genetics, Klebsiella Infections, Klebsiella pneumoniae genetics
- Abstract
To characterize phenotypically and genotypically an isolate of multidrug-resistant (MDR) K. pneumoniae from a patient with septicemia in a hospital in Recife-PE, Brazil, resistance and virulence genes were investigated using PCR and sequencing the amplicons, and the plasmid DNA was also sequenced. The K74-A3 isolate was resistant to all β-lactams, including carbapenems, as well as to aminoglycosides and quinolones. By conducting a PCR analysis and sequencing, the variants bla
NDM-7 associated with blaKPC-2 and the cps, wabG, fim-H, mrkD and entB virulence genes were identified. The analysis of plasmid revealed the presence of blaCTX-M15 , aac(3)-IVa, aph(3')-Ia, aph(4)-Ia, aac(6')ib-cr, mph(A) and catB3, and also the plasmids IncX3, IncFIB, IncQ1, ColRNAI and ColpVC. To our knowledge, this is the first report of the blaNDM-7 gene in Recife-PE and we suggest that this variant is located in IncX3. These results alert us to the risk of spreading an isolate with a vast genetic arsenal of resistance, in addition to which several plasmids are present that favor the horizontal transfer of these genes., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2022
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198. Magnetoelastic Resonance Sensors: Principles, Applications, and Perspectives.
- Author
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G Saiz P, Fernández de Luis R, Lasheras A, Arriortua MI, and Lopes AC
- Subjects
- Magnetics, Transducers, Biosensing Techniques methods
- Abstract
Magnetoelastic resonators are gaining attention as an incredibly versatile and sensitive transduction platform for the detection of varied physical, chemical, and biological parameters. These sensors, based on the coupling effect between mechanical and magnetic properties of ME platforms, stand out in comparison to alternative technologies due to their low cost and wireless detection capability. Several parameters have been optimized over the years to improve their performance, such as their composition, surface functionalization, or shape geometry. In this review, the working principles, recent advances, and future perspectives of magnetoelastic resonance transducers are introduced, highlighting their potentials as a versatile platform for sensing applications. First, the fundamental principles governing the magnetoelastic resonators performance are introduced as well as the most common magnetoelastic materials and their main fabrication methods are described. Second, the versatility and technical feasibility of magnetoelastic resonators for biological, chemical, and physical sensing are highlighted and the most recent results and functionalization processes are summarized. Finally, the forefront advances to further improve the performance of magnetoelastic resonators for sensing applications have been identified.
- Published
- 2022
- Full Text
- View/download PDF
199. Virulence factors of Proteus mirabilis clinical isolates carrying bla KPC-2 and bla NDM-1 and first report bla OXA-10 in Brazil.
- Author
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Beltrão EMB, Oliveira ÉM, Scavuzzi AML, Firmo EF, and Lopes ACS
- Subjects
- Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Brazil, Humans, Microbial Sensitivity Tests, beta-Lactamases genetics, Proteus mirabilis genetics, Virulence Factors genetics
- Abstract
Introduction: Proteus mirabilis is one of the main pathogens that cause urinary tract infections. Therefore, the aim of this study was to analyze and compare the genetic profile of 36 clinical isolates of P. mirabilis that carry and do not carry the bla
KPC and blaNDM gene with respect to virulence factors (mrpG, pmfA, ucaA, nrpG and pbtA) and antimicrobial resistance (blaVIM, blaIMP , blaSPM , blaGES, blaOXA-23-like , blaOXA-48-like , blaOXA-58-like and blaOXA-10-like )., Methods: The virulence and resistance genes were investigated by using PCR and sequencing., Results: ERIC-PCR typing showed that the isolates showed multiclonal dissemination and high genetic variability. The gene that was most found blaOXA-10-like (n = 18), followed by blaKPC (n = 10) and blaNDM (n = 8). To our knowledge, this is the first report of blaOXA-10 in P. mirabilis in Brazil, as well as the first report of the occurrence of P. mirabilis co-carrying blaOXA-10 /blaKPC and blaOXA-10 /blaNDM . The blaNDM or blaKPC carrier isolates showed important virulence genes, such as ucaA (n = 8/44.4%), pbtA (n = 10/55.5%) and nrpG (n = 2/11.1%). However, in general, the non-carrier isolates of blaKPC and blaNDM showed a greater number of virulence genes when compared to the carrier group., Conclusion: Clinical isolates of P. mirabilis, in addition to being multi-drug resistant, presented efficient virulence factors that can establish infection outside the gastrointestinal tract., (Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)- Published
- 2022
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200. From In Vitro Data to In Vivo Interspecies Danger Communication: A Study of Chemosensing via the Mouse Grueneberg Ganglion.
- Author
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Lopes AC, Brechbühl J, Ferreira F, Amez-Droz M, and Broillet MC
- Abstract
In the wild, mice have developed survival strategies to detect volatile cues that warn them of potential danger. Specific olfactory neurons found in the Grueneberg ganglion olfactory subsystem can detect alarm pheromones emitted by stressed conspecifics, as well as kairomones involuntarily released by their predators. These volatile chemical cues allow intra- and interspecies communication of danger, respectively. Alarm pheromones, kairomones and bitter taste ligands share a common chemical motif containing sulfur or nitrogen. Interestingly, three specific bitter taste receptors (TAS2Rs) have been found in the Grueneberg ganglion neurons that are implicated in danger signalling pathways. We have recently developed a TAS2R-expressing heterologous system that mimics the Grueneberg ganglion neuron responses after kairomone stimulation. Here, we demonstrated by in vitro, ex vivo and in vivo experiments that the biological secretions from the raccoon ( Procyon lotor ) and the skunk ( Mephitis mephitis ) were acting as potent sources of kairomones. They activated the Grueneberg ganglion neurons and induced fear-related behaviours in mice. Identification of new sources of semiochemicals is a first step towards an understanding of the interspecies danger communication that takes place in the Grueneberg ganglion.
- Published
- 2022
- Full Text
- View/download PDF
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