Danilo Elias Xavier

@fiocruz.br

Microbiologia
INSTITUTO AGGEU MAGALHÃES



                          

https://researchid.co/danilo.xavier

RESEARCH INTERESTS

Antimicrobial resistance; Bacterial genetics and epidemiology

25

Scopus Publications

1225

Scholar Citations

16

Scholar h-index

18

Scholar i10-index

Scopus Publications

  • Antibacterial and Antibiofilm Potential of Bacterial Cellulose Hydrogel Containing Vancomycin against Multidrug-Resistant Staphylococcus aureus and Staphylococcus epidermidis
    Ana Alice Venancio Correia, Luís André de Almeida Campos, Hanne Lazla Rafael de Queiroz Macêdo, Davi de Lacerda Coriolano, Maria Anndressa Alves Agreles, Danilo Elias Xavier, Rafaela de Siqueira Ferraz-Carvalho, José Lamartine de Andrade Aguiar, and Isabella Macário Ferro Cavalcanti

    MDPI AG
    The present study aimed to evaluate the in vitro antibacterial and antibiofilm activity of bacterial cellulose hydrogel produced by Zoogloea sp. (HYDROGEL) containing vancomycin (VAN) against bacterial strains that cause wound infections, such as multidrug-resistant (MDR) Staphylococcus aureus and Staphylococcus epidermidis. Initially, HYDROGEL was obtained from sugar cane molasses, and scanning electron microscopy (SEM) was performed to determine morphological characteristics. Then, VAN was incorporated into HYDROGEL (VAN-HYDROGEL). The antibacterial activity of VAN, HYDROGEL, and VAN-HYDROGEL was assessed using the broth microdilution method to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) against methicillin-sensitive S. aureus (MSSA) ATCC 25923, methicillin-resistant S. aureus (MRSA) ATCC 33591, S. epidermidis INCQS 00016 (ATCC 12228), five clinical isolates of MRSA, and nine clinical isolates of methicillin-resistant S. epidermidis, following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Additionally, the antibacterial activity of VAN, HYDROGEL, and VAN-HYDROGEL was studied using the time-kill assay. Subsequently, the antibiofilm activity of VAN, HYDROGEL, and VAN-HYDROGEL was evaluated using crystal violet and Congo red methods, as well as SEM analysis. VAN and VAN-HYDROGEL showed bacteriostatic and bactericidal activity against MRSA and methicillin-resistant S. epidermidis strains. HYDROGEL did not show any antibacterial activity. Analysis of the time-kill assay indicated that HYDROGEL maintained the antibacterial efficacy of VAN, highlighting its efficiency as a promising carrier. Regarding antibiofilm activity, VAN and HYDROGEL inhibited biofilm formation but did not demonstrate biofilm eradication activity against methicillin-resistant S. aureus and S. epidermidis strains. However, it was observed that the biofilm eradication potential of VAN was enhanced after incorporation into HYDROGEL, a result also proven through images obtained by SEM. From the methods carried out in this study, it was possible to observe that HYDROGEL preserved the antibacterial activity of vancomycin, aside from exhibiting antibiofilm activity and enhancing the antibiofilm effect of VAN. In conclusion, this study demonstrated the potential of HYDROGEL as a candidate and/or vehicle for antibiotics against MDR bacteria that cause wound infections.


  • High prevalence of GR2 and GR4 plasmids in Acinetobacter baumannii strains from Brazil
    Beatriz Souza Toscano de Melo, Danilo Elias Xavier, Nilma Cintra Leal, and Túlio de Lima Campos

    Oxford University Press (OUP)
    Abstract Acinetobacter baumannii is Gram-negative pathogen with extensive role in healthcare-associated infections (HAIs). Plasmids in this species are important carriers of antimicrobial resistance genes. In this work, we investigated the plasmids of 227 Brazilian A. baumannii genomes. A total of 389 plasmid sequences with 424 Rep proteins typed to 22 different homology groups (GRs) were identified. The GR2 plasmid group was the most predominant (40.6%), followed by the GR4 group (16.7%), representing ∼57% of all plasmids. There is a wide distribution of plasmids among the isolates and most strains carry more than one plasmid. Our analyses revealed a significant prevalence of GR4 plasmids in Brazilian A. baumannii genomes carrying several antimicrobial resistance genes, notably to carbapenem (39.43%). These plasmids harbor a MOBQ relaxase that might confer increased spreading potential in the environment. Most plasmids of the predominant groups belong to the same plasmid taxonomic unit (PTU-Pse7) and have a AbkA/AbkB toxin–antitoxin system that has a role in plasmid stability and dissemination of carbapenem resistance genes. The results of this work should contribute to our understanding of the molecular content of plasmids in a large and populous country, highlighting the importance of genomics for enhanced epidemiological surveillance.

  • Description of a new non-Tn4401 element (NTE<inf>KPC</inf>-IIe) harboured on IncQ plasmid in Citrobacter werkmanii from recreational coastal water
    Eloiza H. Campana, Gabriela B. Kraychete, Lara F. Montezzi, Danilo E. Xavier, and Renata C. Picão

    Elsevier BV

  • Genomic insights of Acinetobacter baumannii ST374 reveal wide and increasing resistome and virulome
    Nayara Helisandra Fedrigo, Danilo Elias Xavier, Louise Cerdeira, Bruna Fuga, Paulo Victor Batista Marini, Danielle Rosani Shinohara, Floristher Elaine Carrara-Marroni, Nilton Lincopan, and Maria Cristina Bronharo Tognim

    Elsevier BV

  • Diverse and emerging molecular mechanisms award polymyxins resistance to Enterobacteriaceae clinical isolates from a tertiary hospital of Recife, Brazil
    Igor Vasconcelos Rocha, Natally dos Santos Silva, Carlos Alberto das Neves Andrade, Cláudia Fernanda de Lacerda Vidal, Nilma Cintra Leal, and Danilo Elias Xavier

    Elsevier BV
    OBJECTIVES To describe the molecular mechanisms of polymyxins resistance in five Enterobacteriaceae clinical isolates in a tertiary hospital from Recife, Brazil. METHODS The species identification and the susceptibility to antimicrobials were firstly performed by automatized methods and polymyxin resistance was confirmed by broth microdilution methods. The genetic basis of resistance was characterized with WGS analyses to study their resistome, plasmidome and mobilome, by BLAST searches on reference databases. RESULTS Five (5%) Enterobacteriaceae isolates, comprising Escherichia coli (n = 2), Klebsiella pneumoniae (n = 2) and Citrobacter freundii (n = 1) species, exhibit polymyxin resistance. The mcr-1.1 gene was found in identical IncX4-plasmids harbored by both K. pneumoniae C119 (PolB MIC = 512 mg/L) and E. coli C153 (PolB MIC = 8 mg/L). The remaining E. coli strain C027 harbored the mcr-5.1 gene on an undefined Inc-plasmid (PolB MIC 256 mg/L). Some amino acid substitutions in PmrA (S29G, G144S), PmrB (S202P; D283G, W350*, Y258N) and PhoP (I44L) was detected among the E. coli clinical isolates, however they were also found in colistin-susceptible strains and predicted as neutral alterations. The mgrB of the ST54 KPC-2-producing K. pneumoniae C151 (PolB MIC = 32 g/mL) was interrupted at 69 nt by the IS903 element. The ST117 C. freundii C156 (PolB MIC = 256 mg/L) showed the A91T substitution on HAMP domain of the histidine kinase sensor CrrB, predicted as deleterious and deemed the remarkable determinant to polymyxins resistance in this strain. CONCLUSION Diverse mechanisms of polymyxins resistance were identified among clinical Enterobacteriaceae from a tertiary hospital of Recife, Brazil, such as plasmid-mediated MCR-1 and MCR-5; IS903-interruption of mgrB and mutation in CrrAB regulatory system. These findings highlight the involvement of the identified plasmids on mcr dissemination among Enterobacteriaceae; warn about co-selection of the polymyxin-resistant and KPC-producer K. pneumoniae ΔmgrB lineage by carbapenems usage; and demonstrate potential role of CrrAB on emerging of polymyxin resistance among Enterobacteriaceae, besides Klebsiella genera.

  • Comparative Genomics of Acinetobacter baumannii Clinical Strains From Brazil Reveals Polyclonal Dissemination and Selective Exchange of Mobile Genetic Elements Associated With Resistance Genes
    Nilma C. Leal, Túlio L. Campos, Antonio M. Rezende, Cássia Docena, Carina L. Mendes-Marques, Felipe L. de Sá Cavalcanti, Gabriel L. Wallau, Igor V. Rocha, Carmelita L. B. Cavalcanti, Dyana L. Veras,et al.

    Frontiers Media SA
    Acinetobacter baumannii is an opportunistic bacterial pathogen infecting immunocompromised patients and has gained attention worldwide due to its increased antimicrobial resistance. Here, we report a comparative whole-genome sequencing and analysis coupled with an assessment of antibiotic resistance of 46 Acinetobacter strains (45 A. baumannii plus one Acinetobacter nosocomialis) originated from five hospitals from the city of Recife, Brazil, between 2010 and 2014. An average of 3,809 genes were identified per genome, although only 2,006 genes were single copy orthologs or core genes conserved across all sequenced strains, with an average of 42 new genes found per strain. We evaluated genetic distance through a phylogenetic analysis and MLST as well as the presence of antibiotic resistance genes, virulence markers and mobile genetic elements (MGE). The phylogenetic analysis recovered distinct monophyletic A. baumannii groups corresponding to five known (ST1, ST15, ST25, ST79, and ST113) and one novel ST (ST881, related to ST1). A large number of ST specific genes were found, with the ST79 strains having the largest number of genes in common that were missing from the other STs. Multiple genes associated with resistance to β-lactams, aminoglycosides and other antibiotics were found. Some of those were clearly mapped to defined MGEs and an analysis of those revealed known elements as well as a novel Tn7-Tn3 transposon with a clear ST specific distribution. An association of selected resistance/virulence markers with specific STs was indeed observed, as well as the recent spread of the OXA-253 carbapenemase encoding gene. Virulence genes associated with the synthesis of the capsular antigens were noticeably more variable in the ST113 and ST79 strains. Indeed, several resistance and virulence genes were common to the ST79 and ST113 strains only, despite a greater genetic distance between them, suggesting common means of genetic exchange. Our comparative analysis reveals the spread of multiple STs and the genomic plasticity of A. baumannii from different hospitals in a single metropolitan area. It also highlights differences in the spread of resistance markers and other MGEs between the investigated STs, impacting on the monitoring and treatment of Acinetobacter in the ongoing and future outbreaks.

  • Occurrence of methicillin-resistant staphylococcus aureus in ready-to-eat raw fish from Japanese Cuisine Restaurants in Salvador, Brazil
    JOELZA SILVA CARVALHO, ANTENOR FERREIRA LEAL NETO, ISABELA MACIEL MELO, LUANA MILEN VARJÃO, CARLOS ALBERTO DAS NEVES ANDRADE, DANILO ELIAS XAVIER, NILMA CINTRA LEAL, and ROGERIA COMASTRI DE CASTRO ALMEIDA

    International Association for Food Protection
    ABSTRACT The presence of methicillin-resistant Staphylococcus aureus (MRSA) strains in food products is a major issue for food safety. The present study was conducted to evaluate the occurrence and antimicrobial resistance profile of S. aureus, focusing on MRSA isolates, in ready-to-eat sashimi from Japanese restaurants in Salvador, Brazil. A total of 127 sashimi samples were collected directly from the take-out service in 16 restaurants. The staphylococcal isolates were identified morphologically and biochemically with standard laboratory procedures. S. aureus isolates were tested with a disk diffusion assay against seven antibiotics, and the cefoxitin and oxacillin were used to identify MRSA strains. Isolates with the MRSA phenotype were confirmed with a PCR assay. S. aureus was found in 73% of the sashimi samples, including sashimi from tuna (75.5% of samples) and salmon (72.5% of samples). Among those positive samples, 37% were contaminated with MRSA strains, found among 38.8% of salmon sashimi and 34.0% of tuna sashimi. Penicillin resistance was the most common type of antimicrobial resistance, found in 65.5% of the sashimi samples, followed by resistance to tetracycline (22.5%), erythromycin (16.0%), and ciprofloxacin (3.2%). Only two S. aureus isolates collected from different fish samples and restaurants had presumed resistance to vancomycin. The high prevalence of S. aureus and MRSA in these sashimi samples indicates a potential risk for foodborne disease, especially MRSA, spreading in the community. HIGHLIGHTS

  • Rapid detection of echinocandins resistance by MALDI-TOF MS in Candida parapsilosis complex
    Ana Emília M. Roberto, Danilo E. Xavier, Esteban E. Vidal, Cláudia Fernanda de L. Vidal, Rejane P. Neves, and Reginaldo G. de Lima-Neto

    MDPI AG
    Mass spectrometry by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) was used to identify and differentiate the pattern of susceptibility of clinical isolates of Candida parapsilosis complex. 17 C. parapsilosis sensu stricto, 2 C. orthopsilosis, and 1 C. metapsilosis strains were obtained from blood cultures, and three different inocula (103, 105, and 107 CFU/mL) were evaluated against three echinocandins at concentrations ranging from 0.03 to 16 µg/mL after incubation of 1 h, 2 h, and 3 h. Drug-free control was used. The spectra obtained at these concentrations were applied to generate composite correlation index (CCI) matrices for each yeast individually. After cross correlations and autocorrelations of each spectra with null (zero) and maximal (16) concentrations, the CCI was used as separation parameter among spectra. Incubation time and inoculum were critical factors to reach higher precision and reliability of this trial. With an incubation time of 3 h and inoculum of 107 CFU/mL, it was possible to determine the breakpoint of the clinical yeasts by MALDI-TOF that presented high agreement with the clinical laboratory standard institute (CLSI) reference method. Herein, we show that mass spectrometry using the MALDI-TOF technique is powerful when it exploits antifungal susceptibility testing assays.

  • A novel plasmid-encoded mcr-4.3 gene in a colistin-resistant Acinetobacter baumannii clinical strain
    Natacha Martins-Sorenson, Erik Snesrud, Danilo Elias Xavier, Luciana Camila Cacci, Anthony T Iavarone, Patrick McGann, Lee W Riley, and Beatriz Meurer Moreira

    Oxford University Press (OUP)
    Abstract Objectives To identify the molecular mechanism of colistin resistance in an MDR Acinetobacter baumannii clinical strain isolated in 2008 from a meningitis case in Brazil. Methods Long- and short-read WGS was used to identify colistin resistance genes in A. baumannii strain 597A with a colistin MIC of 64 mg/L. MS was used to analyse lipid A content. mcr was cloned into pET-26b (+) and transformed into Escherichia coli BL21(λDE3)pLysS for analysis. Results A novel plasmid (pAb-MCR4.3) harbouring mcr-4.3 within a Tn3-like transposon was identified. The A. baumannii 597A lipid A MS spectra showed a main molecular ion peak at m/z=2034, which indicated the addition of phosphoethanolamine to the lipid A structure. E. coli BL21 transformed with pET-26b-mcr-4.3 gained colistin resistance with a colistin MIC of 8 mg/L. Conclusions Colistin resistance in A. baumannii 597A was correlated with the presence of a novel plasmid-encoded mcr-4.3 gene.

  • High-resolution genome-wide analysis is essential for the identification of ambiguous Aeromonas strains
    Beatriz Souza Toscano de Melo, Carina Lucena Mendes-Marques, Túlio de Lima Campos, Alzira Maria Paiva de Almeida, Nilma Cintra Leal, and Danilo Elias Xavier

    Oxford University Press (OUP)
    ABSTRACT Aeromonads are mainly opportunistic pathogens; however, many species are emerging as important human pathogens. Therefore, monitoring these bacteria and their accurate characterization of its species is highly important. Aeromonas Aer593 strain was recovered from a diarrhoea outbreak and did not group with any previously described Aeromonas species by housekeeping gene sequencing. To clarify the taxonomic position of Aer593, its genome was sequenced and analysed by multilocus phylogenetic analysis (MLPA), in silico DNA–DNA hybridization (isDDH), average nucleotide identity (ANI) and core genome-based phylogenetic analyzes. The MLPA with the housekeeping genes gyrB, rpoD, recA, dnaJ, gyrA and dnaX ranked the Aer593 isolate into an independent branch suggesting that it could represent a new species. However, the identity percentages of Aer593 to A. caviae strains using robust genomic analysis by isDDH and ANI were at least 81.3% and 97.8%, respectively, defining Aer593 as A. caviae. Multilocus sequence typing (MLST) presented an exact match against only a single allele (groL96) and the novel ST648 was assigned for this strain. The core genome-based phylogenetic analyses with a total of 863 orthologous genes also grouped the Aer593 isolate with A. caviae reference strains. These findings warn about the possibility of misidentification of some Aeromonas strains by MLPA and show that high-resolution genome-wide analysis is essential for the correct identification of ambiguous Aeromonas strains.

  • Multidrug-resistant Acinetobacter baumannii clones persist on hospital inanimate surfaces
    Igor Vasconcelos Rocha, Danilo Elias Xavier, Karoline Rissele Henrique de Almeida, Sibele Ribeiro de Oliveira, and Nilma Cintra Leal

    Elsevier BV
    Acinetobacter baumannii is one of the most frequent Gram-negative opportunistic pathogens associated with hospital-acquired infection worldwide. We briefly describe A. baumannii isolates that were recovered from surrounding ICU bed surfaces, exhibiting multidrug resistance phenotype and belonging to some widely spread clonal complexes of clinical A. baumannii isolates.

  • Ciprofloxacin-resistant and extended-spectrum β-lactamase-producing Escherichia coli ST410 strain carrying the mcr-1 gene associated with bloodstream infection
    Igor Vasconcelos Rocha, Carlos Alberto das Neves Andrade, Túlio de Lima Campos, Antonio Mauro Rezende, Nilma Cintra Leal, Cláudia Fernanda de Lacerda Vidal, and Danilo Elias Xavier

    Elsevier BV

  • High frequency of OXA-253-producing Acinetobacter baumannii in different hospitals in Recife, Brazil
    Felipe Lira de Sá Cavalcanti, Carina Lucena Mendes-Marques, Crhisllane Rafaele dos Santos Vasconcelos, Túlio de Lima Campos, Antonio Mauro Rezende, Danilo Elias Xavier, Nilma Cintra Leal, Osvaldo Pompilio de-Melo-Neto, Marcia Maria Camargo de Morais, and Tereza Cristina Leal-Balbino

    American Society for Microbiology
    ABSTRACT Here, we report the isolation of 31 Acinetobacter baumannii strains producing OXA-253 in a single large Brazilian city. These strains belonged to five different sequence types (STs), including 4 STs not previously associated with bla OXA-253. In all strains, the bla OXA-253 gene was located in a plasmid within a genetic environment similar to what was found previously in Brazil and Italy. The reported data emphasize the successful transmission of the bla OXA-253 gene through a large area and the tendency for this resistance determinant to remain in the A. baumannii population.

  • Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil
    Eloiza Helena Campana, Danilo Elias Xavier, Fernanda Villas-Boas Petrolini, Jhonatha Rodrigo Cordeiro-Moura, Maria Rita Elmor de Araujo, and Ana Cristina Gales

    Elsevier BV
    The mechanisms involved in the uncommon resistance phenotype, carbapenem resistance and broad-spectrum cephalosporin susceptibility, were investigated in 25 Pseudomonas aeruginosa clinical isolates that exhibited this phenotype, which were recovered from three different hospitals located in São Paulo, Brazil. The antimicrobial susceptibility profile was determined by CLSI broth microdilution. β-lactamase-encoding genes were investigated by PCR followed by DNA sequencing. Carbapenem hydrolysis activity was investigated by spectrophotometer and MALDI-TOF assays. The mRNA transcription level of oprD was assessed by qRT-PCR and the outer membrane proteins profile was evaluated by SDS-PAGE. Genetic relationship among P. aeruginosa isolates was assessed by PFGE. Carbapenems hydrolysis was not detected by carbapenemase assay in the carbapenem-resistant and cephalosporin-susceptible P. aueruginosa clinical isolates. OprD decreased expression was observed in all P. aeruginosa isolates by qRT-PCR. The outer membrane protein profile by SDS-PAGE suggested a change in the expression of the 46kDa porin that could correspond to OprD porin. The isolates were clustered into 17 genotypes without predominance of a specific PFGE pattern. These results emphasize the involvement of multiple chromosomal mechanisms in carbapenem-resistance among clinical isolates of P. aeruginosa, alert for adaptation of P. aeruginosa clinical isolates under antimicrobial selective pressure and make aware of the emergence of an uncommon phenotype among P. aeruginosa clinical isolates.

  • Identification of lactic acid bacteria in fruit pulp processing byproducts and potential probiotic properties of selected Lactobacillus strains
    Estefânia F. Garcia, Winnie A. Luciano, Danilo E. Xavier, Whyara C. A. da Costa, Kleber de Sousa Oliveira, Octávio L. Franco, Marcos A. de Morais Júnior, Brígida T. L. Lucena, Renata C. Picão, Marciane Magnani,et al.

    Frontiers Media SA
    This study aimed to identify lactic acid bacteria (LAB) in byproducts of fruit (Malpighia glabra L., Mangifera indica L., Annona muricata L., and Fragaria vesca L.) pulp processing. Fifty strains of LAB were identified using matrix-assisted laser desorption/ionization–time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequence (16S rRNA) analysis. Species belonging to Lactobacillus genus were the predominant LAB in all fruit pulp processing byproducts. The average congruency between the MALDI-TOF MS and 16S rRNA in LAB species identification reached 86%. Isolates of L. plantarum, L. brevis, L. pentosus, L. lactis and L. mesenteroides were identified with 100% congruency. MALDI-TOF MS and 16S rRNA analysis presented 86 and 100% efficiency of LAB species identification, respectively. Further, five selected Lactobacillus strains (L. brevis 59, L. pentosus 129, L. paracasei 108, L. plantarum 49, and L. fermentum 111) were evaluated for desirable probiotic-related properties and growth behavior on two different cultivation media. The exposure to pH 2.0 sharply decreased the counts of the different Lactobacillus strains after a 1 or 2 h incubation, while varied decreases were noted after 3 h of exposure to pH 3.0. Overall, the exposure to pH 5.0 and to bile salts (0.15, 0.30, and 1.00%) did not decrease the counts of the Lactobacillus strains. All tested Lactobacillus strains presented inhibitory activity against Staphylococcus aureus, Salmonella Typhimurium, Salmonella Enteritidis, Listeria monocytogenes and Escherichia coli, and presented variable susceptibility to different antibiotics. The selected Lactobacillus strains presented satisfactory and reproducible growth behavior. In conclusion, MALDI-TOF MS and 16S rRNA analysis revealed high efficiency and congruency for LAB species identification, and the selected Lactobacillus strains may be candidates for further investigation of novel probiotic strains.

  • Comparative analysis of the complete genome of KPC-2-producing Klebsiella pneumoniae Kp13 reveals remarkable genome plasticity and a wide repertoire of virulence and resistance mechanisms
    Pablo Ivan Pereira Ramos, Renata Christina Picão, Luiz Gonzaga Paula de Almeida, Nicholas Costa B Lima, Raquel Girardello, Ana Carolina P Vivan, Danilo E Xavier, Fernando G Barcellos, Marsileni Pelisson, Eliana C Vespero,et al.

    Springer Science and Business Media LLC
    BackgroundKlebsiella pneumoniae is an important opportunistic pathogen associated with nosocomial and community-acquired infections. A wide repertoire of virulence and antimicrobial resistance genes is present in K. pneumoniae genomes, which can constitute extra challenges in the treatment of infections caused by some strains. K. pneumoniae Kp13 is a multidrug-resistant strain responsible for causing a large nosocomial outbreak in a teaching hospital located in Southern Brazil. Kp13 produces K. pneumoniae carbapenemase (KPC-2) but is unrelated to isolates belonging to ST 258 and ST 11, the main clusters associated with the worldwide dissemination of KPC-producing K. pneumoniae. In this report, we perform a genomic comparison between Kp13 and each of the following three K. pneumoniae genomes: MGH 78578, NTUH-K2044 and 342.ResultsWe have completely determined the genome of K. pneumoniae Kp13, which comprises one chromosome (5.3 Mbp) and six plasmids (0.43 Mbp). Several virulence and resistance determinants were identified in strain Kp13. Specifically, we detected genes coding for six beta-lactamases (SHV-12, OXA-9, TEM-1, CTX-M-2, SHV-110 and KPC-2), eight adhesin-related gene clusters, including regions coding for types 1 (fim) and 3 (mrk) fimbrial adhesins. The rmtG plasmidial 16S rRNA methyltransferase gene was also detected, as well as efflux pumps belonging to five different families. Mutations upstream the OmpK35 porin-encoding gene were evidenced, possibly affecting its expression. SNPs analysis relative to the compared strains revealed 141 mutations falling within CDSs related to drug resistance which could also influence the Kp13 lifestyle. Finally, the genetic apparatus for synthesis of the yersiniabactin siderophore was identified within a plasticity region. Chromosomal architectural analysis allowed for the detection of 13 regions of difference in Kp13 relative to the compared strains.ConclusionsOur results indicate that the plasticity occurring at many hierarchical levels (from whole genomic segments to individual nucleotide bases) may play a role on the lifestyle of K. pneumoniae Kp13 and underlie the importance of whole-genome sequencing to study bacterial pathogens. The general chromosomal structure was somewhat conserved among the compared bacteria, and recombination events with consequent gain/loss of genomic segments appears to be driving the evolution of these strains.

  • Metallo-β-lactamase-production in meropenem-susceptible Pseudomonas aeruginosa isolates: Risk for silent spread
    Renata Cristina Picão, Floristher Elaine Carrara-Marroni, Ana Cristina Gales, Emerson José Venâncio, Danilo Elias Xavier, Maria Cristina Bronharo Tognim, and Jacinta Sanchez Pelayo

    FapUNIFESP (SciELO)
    The aim of this study was to characterize two metallo-β-lactamases (MBLs)-producing Pseudomonas aeruginosa clinical isolates showing meropenem susceptibility. Antimicrobial susceptibility was assessed by automated testing and Clinical and Laboratory Standards Institute agar dilution method. MBL production was investigated by phenotypic tests. Molecular typing was determined by pulsed field gel electrophoresis (PFGE). MBL-encoding genes, as well as their genetic context, were identified by polymerase chain reaction (PCR) and sequencing. The location of blaIMP-16 was determined by plasmid electrophoresis, Southern blot and hybridization. Transcriptional levels of blaIMP-16, mexB, mexD, mexF, mexY, ampC and oprD were determined by semi-quantitative real time PCR. The P. aeruginosa isolates studied, Pa30 and Pa43, showed imipenem and meropenem susceptibility by automated testing. Agar dilution assays confirmed meropenem susceptibility whereas both isolates showed low level of imipenem resistance. Pa30 and Pa43 were phenotypically detected as MBL producers. PFGE revealed their clonal relatedness. blaIMP-16 was identified in both isolates, carried as a single cassette in a class 1 integron that was embedded in a plasmid of about 60-Kb. Pa30 and Pa43 overexpressed MexAB-OprM, MexCD-OprJ and MexXY-OprM efflux systems and showed basal transcriptional levels of ampC and oprD. MBL-producing P. aeruginosa that are not resistant to meropenem may represent a risk for therapeutic failure and act as silent reservoirs of MBL-encoding genes.

  • Beta-lactam resistance mechanisms in Pseudomonas aeruginosa strains causing bloodstream infections: Comparative results between Brazilian and American isolates
    Lorena C.C. Fehlberg, Danilo E. Xavier, Paula P. Peraro, Alexandre R. Marra, Michael B. Edmond, and Ana C. Gales

    Mary Ann Liebert Inc
    This study evaluated the presence of distinct mechanisms of beta-lactam resistance in 122 Pseudomonas aeruginosa isolates, causing bloodstream infections at Hospital São Paulo (HSP, Brazil; 82 isolates) and Virginia Commonwealth University Medical Center (VCU, United States; 40 isolates). By Clinical Laboratory Standards Institute agar dilution, Brazilian P. aeruginosa isolates showed higher resistance rates to most antimicrobials tested than those collected from the United States, except for ciprofloxacin. Carbapenem hydrolysis was detected in seven P. aeruginosa from HSP, in which bla(SPM-1) (n=5), bla(IMP-1) (n=1), and bla(IMP-16) (n=1) were detected by polymerase chain reaction (PCR) followed by DNA sequencing. The production of GES-5 was observed in 1.25% of HSP isolates. No extended-spectrum beta-lactamase-encoding genes were detected in the VCU isolates. Expression of efflux systems genes (mexB, mexD, mexF, and mexY) was evaluated by quantitative reverse transcriptase-PCR. In HSP isolates MexXY-OprM (41.4%) efflux system was more frequently overexpressed, in contrast to what was observed in the VCU isolates, where both MexXY-OprM (25.0%) and MexAB-OprM (25.0%) were equally overexpressed. The oprD downregulation was similar among isolates collected from the HSP (92.7%) and VCU (95.0%). On the other hand, ampC overexpression was observed only among HSP isolates (31.7%). The distinct antimicrobial susceptibility profile and mechanisms of beta-lactam resistance found among P. aeruginosa isolated from teaching hospitals located in Brazil and the United States exemplify the importance of local epidemiology in determining antimicrobial resistance rates.

  • Antimicrobial activity of doripenem against Gram-negative pathogens: Results from INVITA-A-DORI Brazilian Study
    Ana Cristina Gales, Heber D. Azevedo, Rosângela Ferraz Cereda, Raquel Girardello, and Danilo Elias Xavier

    Elsevier BV
    In vitro activity of doripenem and comparator antimicrobial agents was evaluated against Gram-negative bacilli recently isolated from Brazilian private hospitals that were enrolled in the INVITA-A-DORI Brazilian Study. A total of 805 unique Gram-negative bacilli were collected from patients hospitalized at 18 medical centers between May/08 and March/09. Each hospital was asked to submit 50 single Gram-negative bacilli isolated from blood, lower respiratory tract or intraabdominal secretions. Bacterial identification was confirmed and antimicrobial susceptibility testing was performed using Clinical Laboratory Standards Institute (CLSI) microdilution method at a central laboratory. CLSI M100-S21 (2011) or US-FDA package insert criteria (tigecycline) was used for interpretation of the antimicrobial susceptibility results. Doripenem was as active as meropenem and more active than imipenem against E. coli and K. pneumoniae isolates. A total of 50.0% of Enterobacter spp. isolates were resistant to ceftazidime but 85.7% of them were inhibited at doripenem MICs < 1 µg/mL. Polymyxin B was the only agent to show potent activity against Acinetobacter spp. (MIC50/90, < 0.5/1 µg/mL) and P. aeruginosa (MIC50/90, 1/2 µg/mL). Although high rates of imipenem (53.1%) and meropenem (44.5%) resistance were detected among P. aeruginosa, doripenem showed MIC50 of 16 µg/mL against imipenem-resistant P. aeruginosa and inhibited a greater number of imipenem-resistant P. aeruginosa (10.5%) at MIC values of < 4 µg/mL than did meropenem (0.0%). In this study, doripenem showed similar in vitro activity to that of meropenem and retained some activity against imipenem-resistant P. aeruginosa isolated from Brazilian medical centers.

  • Antimicrobial activity of ceftobiprole against Gram-negative and Gram-positive pathogens: Results from INVITA-A-CEFTO Brazilian study
    Rosângela Ferraz Cereda, Heber Dias Azevedo, Raquel Girardello, Danilo Elias Xavier, and Ana C Gales

    FapUNIFESP (SciELO)

  • Efflux pumps expression and its association with porin down-regulation and β-lactamase production among Pseudomonas aeruginosa causing bloodstream infections in Brazil
    Danilo E Xavier, Renata C Picão, Raquel Girardello, Lorena CC Fehlberg, and Ana C Gales

    Springer Science and Business Media LLC
    BackgroundMulti-drug efflux pumps have been increasingly recognized as a major component of resistance in P. aeruginosa. We have investigated the expression level of efflux systems among clinical isolates of P. aeruginosa, regardless of their antimicrobial susceptibility profile.ResultsAztreonam exhibited the highest in vitro activity against the P. aeruginosa isolates studied (64.4% susceptibility), whereas susceptibility rates of imipenem and meropenem were both 47.5%. The MexXY-OprM and MexAB-OprM efflux systems were overexpressed in 50.8% and 27.1% of isolates studied, respectively. Overexpression of the MexEF-OprN and MexCD-OprJ systems was not observed. AmpC β-lactamase was overexpressed in 11.9% of P. aeruginosa isolates. In addition, decreased oprD expression was also observed in 69.5% of the whole collection, and in 87.1% of the imipenem non-susceptible P. aeruginosa clinical isolates. The MBL-encoding genes blaSPM-1 and blaIMP-1 were detected in 23.7% and 1.7% P. aeruginosa isolates, respectively. The blaGES-1 was detected in 5.1% of the isolates, while blaGES-5 and blaCTX-M-2 were observed in 1.7% of the isolates evaluated. In the present study, we have observed that efflux systems represent an adjuvant mechanism for antimicrobial resistance.ConclusionsEfflux systems in association of distinct mechanisms such as the porin down-regulation, AmpC overproduction and secondary β-lactamases play also an important role in the multi-drug resistance phenotype among P. aeruginosa clinical isolates.

  • Cloverleaf test (modified Hodge test) for detecting carbapenemase production in Klebsiella pneumoniae: be aware of false positive results
    C. G. Carvalhaes, R. C. Picao, A. G. Nicoletti, D. E. Xavier, and A. C. Gales

    Oxford University Press (OUP)
    OBJECTIVES The aim of this study was to evaluate the presence of carbapenemases in a Klebsiella pneumoniae collection and the performance of the modified Hodge test (MHT) to correctly identify this phenotype. METHODS Twenty-eight K. pneumoniae clinical isolates with reduced susceptibility to carbapenems were evaluated. Antimicrobial susceptibility and molecular typing were performed by agar dilution and PFGE, respectively. The MHT was performed using both standard and high inoculum of test organisms. Imipenem hydrolysis was investigated by spectrophotometric assays and carbapenemase-encoding genes were identified by PCR and amplicon sequencing. Porin loss was investigated by both PCR and SDS-PAGE. RESULTS Susceptibility rates for imipenem, meropenem and ertapenem were 93%, 57% and 11%, respectively. The PFGE analysis showed seven unrelated genotypes. By testing standard inoculum and ertapenem or meropenem discs, 25% (n = 7) and 21% (n = 6) of the isolates were classified as carbapenemase producers, respectively. When a higher inoculum was employed, these rates increased to 54% (n = 15) and 43% (n = 12), respectively. No imipenem hydrolysis was detected. PCRs identified bla(CTX-M) in 27 (96%) isolates, of which 2 isolates also carried bla(GES-1.) SDS-PAGE and PCR assays revealed that all isolates had lost at least one outer membrane protein, except for a single isolate that was found to express both OmpK35 and OmpK36. CONCLUSIONS False detection of carbapenemase production was observed by the MHT possibly as a result of extended-spectrum beta-lactamase (ESBL) production coupled with porin loss as reported before. Clinical laboratories must be aware of this fact, especially in geographical areas where ESBL-producing isolates are highly prevalent.

  • Metallo-betalactamase producing Pseudomonas spp. strains isolated in the Hospital Geral de Fortaleza
    Júlio César Nogueira Torres, Everardo Albuquerque Menezes, Maria Rozellê Ferreira Ângelo, Inácio Regis Nascimento Oliveira, Maria Núbia Cavalcante Salviano, Danilo Elias Xavier, and Lauro Santos Filho

    FapUNIFESP (SciELO)
    Pseudomonas sp. e um bacilo gram-negativo ubiquo de vida livre e frequente em ambientes hospitalares. Bacterias produtoras de metalo-betalactamases (MBLs) sao em grande parte resistentes aos betalactâmicos de largo espectro, incluindo cefalosporinas e carbapenens. Este trabalho objetivou detectar cepas de Pseudomonas spp. resistentes ao imipenem e a ceftazidima, assim como identificar aquelas produtoras de MBLs. Foram estudadas (entre junho de 2002 e junho de 2003) 311 cepas isoladas de diversas amostras clinicas no Hospital Geral de Fortaleza (HGF), bem como foram realizados testes de identificacao e sensibilidade pelo sistema de automacao MicroScan®/WalkAway, sendo as cepas multirresistentes confirmadas atraves do metodo de difusao em disco. A triagem para deteccao de amostras produtoras de MBLs foi realizada pelo metodo de dupla difusao, utilizando discos com mercaptoacetato de sodio. Entre essas amostras, 24 (7,71%) demonstraram producao de MBLs e padrao de multirresistencia entre as cepas estudadas. Os antimicrobianos para os quais as cepas apresentaram maior sensibilidade foram a piperacilina/tazobactam com 255 (82%) de sensibilidade, seguido da piperacilina isoladamente, com 229 (73,63%); imipenem com 195 (62,70%); ticarcilina/acido clavulânico com 193 (62,05%); e ceftazidima com 138 (44,37%). A deteccao dessas amostras configura um problema emergente, com importantes implicacoes na terapeutica antimicrobiana.

  • Detection of metallo-β-lactamase producing Pseudomonas aeruginosa isolated in João Pessoa, Paraíba, Brazil
    Lauro Santos Filho, Isabele Beserra Santos, Alexandro Mangueira Lima de Assis, and Danilo Elias Xavier

    FapUNIFESP (SciELO)
    Producers of metallo-b-lactamases (MBLs) have been shown to confer resistance to carbapenems. The present study was undertaken to evaluate the presence of resistance to imipenem and oxymino cephalosporins, as well as MBLs production among clinical isolates of Pseudomonas aeruginosa in Joao Pessoa-PB, Brazil. A total of 198 non-repetitive strains of P. aeruginosa identified by routine techniques were studied. These strains were screened for MBL production, using the double disk diffusion test previously described by Arakawa et al. (2000), as modified by Nakajima et al. (2001), using disks containing sodium mercaptoacetate as inhibitor of MBL. Strains were considered to be MBL producer when they demonstrated a typical expansion in the inhibitory zone by the presence of thiol compound. A total of four strains (2%) showed positive results among the isolates tested. Our findings indicate that the appearance of metallo-b-lactamase in Pseudomonas aeruginosa strains is an emerging problem, with important therapeutic implications, and this fact needs further investigation including the use of molecular methodologies to fully characterize the extent of the problem.

RECENT SCHOLAR PUBLICATIONS

  • Antibacterial and Antibiofilm Potential of Bacterial Cellulose Hydrogel Containing Vancomycin against Multidrug-Resistant Staphylococcus aureus and Staphylococcus epidermidis
    AAV Correia, LA de Almeida Campos, HLR de Queiroz Macdo, ...
    Biology 13 (5), 354 2024

  • Corrigendum to'Description of a new non-Tn4401 element (NTEKPC-IIe) harboured on IncQ plasmid in Citrobacter werkmanii from recreational coastal water'[Journal of Global
    EH Campana, GB Kraychete, LF Montezzi, DE Xavier, RC Pico
    Journal of global antimicrobial resistance 34, 271 2023

  • High prevalence of GR2 and GR4 plasmids in Acinetobacter baumannii strains from Brazil
    BST de Melo, DE Xavier, NC Leal, TL Campos
    Pathogens and Disease 81, ftad022 2023

  • An update on the role of Hfq RNA Chaperone in resistance and virulence of Acinetobacter baumannii
    LCA Silva, NC Leal, DE Xavier
    Revista Preveno de Infeco e Sade 8 (1) 2022

  • Description of a new non-Tn4401 element (NTEKPC-IIe) harboured on IncQ plasmid in Citrobacter werkmanii from recreational coastal water
    EH Campana, GB Kraychete, LF Montezzi, DE Xavier, RC Pico
    Journal of Global Antimicrobial Resistance 29, 207-211 2022

  • Genomic insights of Acinetobacter baumannii ST374 reveal wide and increasing resistome and virulome
    NH Fedrigo, DE Xavier, L Cerdeira, B Fuga, PVB Marini, DR Shinohara, ...
    Infection, Genetics and Evolution 97, 105148 2022

  • Epidemiological profile and detection of resistance genes in bloodstream infection in cancer patients: High occurrence of metallo-β-lactamases in Enterobacteriales
    C Soares, CP Incio, MJB Silva, NC Leal, DE Xavier, V Magalhes, ...
    2021

  • Diverse and emerging molecular mechanisms award polymyxins resistance to Enterobacteriaceae clinical isolates from a tertiary hospital of Recife, Brazil
    IV Rocha, N dos Santos Silva, CA das Neves Andrade, ...
    Infection, Genetics and Evolution 85, 104584 2020

  • Comparative Genomics of Acinetobacter baumannii Clinical Strains From Brazil Reveals Polyclonal Dissemination and Selective Exchange of Mobile Genetic
    NC Leal, TL Campos, AM Rezende, C Docena, CL Mendes-Marques, ...
    Frontiers in Microbiology 11, 1176 2020

  • Occurrence of methicillin-resistant Staphylococcus aureus in ready-to-eat raw fish from Japanese cuisine restaurants in Salvador, Brazil
    JS Carvalho, AFL Neto, IM Melo, LM Varjo, CADN Andrade, DE Xavier, ...
    Journal of Food Protection 83 (6), 991-995 2020

  • Rapid Detection of Echinocandins Resistance by MALDI-TOF MS in Candida parapsilosis Complex
    AEM Roberto, DE Xavier, EE Vidal, CFL Vidal, RP Neves, RG Lima-Neto
    Microorganisms 8 (1), 109 2020

  • A novel plasmid-encoded mcr-4.3 gene in a colistin-resistant Acinetobacter baumannii clinical strain
    N Martins-Sorenson, E Snesrud, DE Xavier, LC Cacci, AT Iavarone, ...
    Journal of Antimicrobial Chemotherapy 75 (1), 60-64 2020

  • High-resolution genome-wide analysis is essential for the identification of ambiguous Aeromonas strains
    BST de Melo, CL Mendes-Marques, TL Campos, AMP Almeida, NC Leal, ...
    FEMS microbiology letters 366 (21), fnz245 2019

  • Multidrug-resistant Acinetobacter baumannii clones persist on hospital inanimate surfaces
    IV Rocha, DE Xavier, KRH Almeida, SR Oliveira, NC Leal
    Brazilian Journal of Infectious Diseases 22 (5), 438-441 2018

  • Staphylococcus spp. resistant in blood cultures and hospital surfaces and the patient safety
    KR Henrique de Almeida, NS Silva, IV Rocha, DE Xavier, NC Lea, ...
    REVISTA DE EPIDEMIOLOGIA E CONTROLE DE INFECCAO 7 (4) 2017

  • Ciprofloxacin-resistant and extended-spectrum β-lactamase-producing Escherichia coli ST410 strain carrying the mcr-1 gene associated with bloodstream infection
    IV Rocha, CA das Neves Andrade, T de Lima Campos, AM Rezende, ...
    International journal of antimicrobial agents 49 (5), 655-656 2017

  • Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil
    EH Campana, DE Xavier, FVB Petrolini, JR Cordeiro-Moura, MRE Araujo, ...
    Brazilian Journal of Infectious Diseases 21 (1), 57-62 2017

  • High frequency of OXA-253-producing Acinetobacter baumannii in different hospitals in Recife, Brazil
    FL de S Cavalcanti, CL Mendes-Marques, CRS Vasconcelos, ...
    Antimicrobial agents and chemotherapy 61 (1), 10.1128/aac. 01309-16 2017

  • Identification of Lactic Acid Bacteria in Fruit Pulp Processing Byproducts and Potential Probiotic Properties of Selected Lactobacillus Strains
    EF Garcia, WA Luciano, DE Xavier, WCA da Costa, K de Sousa Oliveira, ...
    Frontiers in microbiology 7, 1371 2016

  • Identification of lactic acid bacteria in fruit pulp processing byproducts and potential probiotic properties of selected Lactobacillus strains. Front Microbiol 7: 1371
    EF Garcia, WA Luciano, DE Xavier, WCA da Costa, K de Sousa Oliveira, ...
    2016

MOST CITED SCHOLAR PUBLICATIONS

  • Cloverleaf test (modified Hodge test) for detecting carbapenemase production in Klebsiella pneumoniae: be aware of false positive results
    CG Carvalhaes, RC Picao, AG Nicoletti, DE Xavier, AC Gales
    Journal of antimicrobial chemotherapy 65 (2), 249-251 2010
    Citations: 295

  • Efflux pumps expression and its association with porin down-regulation and β-lactamase production among Pseudomonas aeruginosa causing bloodstream
    DE Xavier, RC Pico, R Girardello, LCC Fehlberg, AC Gales
    BMC microbiology 10 (1), 217 2010
    Citations: 171

  • Comparative analysis of the complete genome of KPC-2-producing Klebsiella pneumoniae Kp13 reveals remarkable genome plasticity and a wide repertoire of
    PIP Ramos, RC Pico, LGP de Almeida, NCB Lima, R Girardello, ...
    BMC genomics 15, 1-16 2014
    Citations: 133

  • Identification of Lactic Acid Bacteria in Fruit Pulp Processing Byproducts and Potential Probiotic Properties of Selected Lactobacillus Strains
    EF Garcia, WA Luciano, DE Xavier, WCA da Costa, K de Sousa Oliveira, ...
    Frontiers in microbiology 7, 1371 2016
    Citations: 131

  • A novel plasmid-encoded mcr-4.3 gene in a colistin-resistant Acinetobacter baumannii clinical strain
    N Martins-Sorenson, E Snesrud, DE Xavier, LC Cacci, AT Iavarone, ...
    Journal of Antimicrobial Chemotherapy 75 (1), 60-64 2020
    Citations: 79

  • Multidrug-resistant Acinetobacter baumannii clones persist on hospital inanimate surfaces
    IV Rocha, DE Xavier, KRH Almeida, SR Oliveira, NC Leal
    Brazilian Journal of Infectious Diseases 22 (5), 438-441 2018
    Citations: 44

  • Carbapenem-resistant and cephalosporin-susceptible: a worrisome phenotype among Pseudomonas aeruginosa clinical isolates in Brazil
    EH Campana, DE Xavier, FVB Petrolini, JR Cordeiro-Moura, MRE Araujo, ...
    Brazilian Journal of Infectious Diseases 21 (1), 57-62 2017
    Citations: 40

  • Comparative Genomics of Acinetobacter baumannii Clinical Strains From Brazil Reveals Polyclonal Dissemination and Selective Exchange of Mobile Genetic
    NC Leal, TL Campos, AM Rezende, C Docena, CL Mendes-Marques, ...
    Frontiers in Microbiology 11, 1176 2020
    Citations: 32

  • Metallo-β-lactamase-production in meropenem-susceptible Pseudomonas aeruginosa isolates: risk for silent spread
    RC Pico, FE Carrara-Marroni, AC Gales, EJ Venncio, DE Xavier, ...
    Memrias do Instituto Oswaldo Cruz 107, 747-751 2012
    Citations: 32

  • Antimicrobial activity of doripenem against Gram-negative pathogens: results from INVITA-A-DORI Brazilian study
    AC Gales, HD Azevedo, RF Cereda, R Girardello, DE Xavier, ...
    The Brazilian Journal of Infectious Diseases 15 (6), 513-520 2011
    Citations: 30

  • Ciprofloxacin-resistant and extended-spectrum β-lactamase-producing Escherichia coli ST410 strain carrying the mcr-1 gene associated with bloodstream infection
    IV Rocha, CA das Neves Andrade, T de Lima Campos, AM Rezende, ...
    International journal of antimicrobial agents 49 (5), 655-656 2017
    Citations: 28

  • Beta-lactam resistance mechanisms in Pseudomonas aeruginosa strains causing bloodstream infections: comparative results between Brazilian and American isolates
    LCC Fehlberg, DE Xavier, PP Peraro, AR Marra, MB Edmond, AC Gales
    Microbial Drug Resistance 18 (4), 402-407 2012
    Citations: 28

  • Determinao da produo de metalo-beta-lactamases em amostras de Pseudomonas aeruginosa isoladas em Joo Pessoa, Paraba
    L Santos Filho, IB Santos, AML Assis, DE Xavier
    Jornal Brasileiro de Patologia e Medicina Laboratorial 38, 291-296 2002
    Citations: 28

  • Rapid Detection of Echinocandins Resistance by MALDI-TOF MS in Candida parapsilosis Complex
    AEM Roberto, DE Xavier, EE Vidal, CFL Vidal, RP Neves, RG Lima-Neto
    Microorganisms 8 (1), 109 2020
    Citations: 26

  • Cepas de Pseudomonas spp. produtoras de metalo-betalactamase isoladas no Hospital Geral de Fortaleza
    JCN Torres, EA Menezes, MRF ngelo, IRN Oliveira, MNC Salviano, ...
    Jornal Brasileiro de Patologia e Medicina Laboratorial 42, 313-319 2006
    Citations: 20

  • Identification of lactic acid bacteria in fruit pulp processing byproducts and potential probiotic properties of selected Lactobacillus strains. Front Microbiol 7: 1371
    EF Garcia, WA Luciano, DE Xavier, WCA da Costa, K de Sousa Oliveira, ...
    2016
    Citations: 16

  • Antimicrobial activity of ceftobiprole against Gram-negative and Gram-positive pathogens: results from INVITA-A-CEFTO Brazilian study
    RF Cereda, HD Azevedo, R Girardello, DE Xavier, AC Gales, ...
    The Brazilian Journal of Infectious Diseases 15 (4), 339-348 2011
    Citations: 15

  • High frequency of OXA-253-producing Acinetobacter baumannii in different hospitals in Recife, Brazil
    FL de S Cavalcanti, CL Mendes-Marques, CRS Vasconcelos, ...
    Antimicrobial agents and chemotherapy 61 (1), 10.1128/aac. 01309-16 2017
    Citations: 12

  • Diverse and emerging molecular mechanisms award polymyxins resistance to Enterobacteriaceae clinical isolates from a tertiary hospital of Recife, Brazil
    IV Rocha, N dos Santos Silva, CA das Neves Andrade, ...
    Infection, Genetics and Evolution 85, 104584 2020
    Citations: 9

  • Description of a new non-Tn4401 element (NTEKPC-IIe) harboured on IncQ plasmid in Citrobacter werkmanii from recreational coastal water
    EH Campana, GB Kraychete, LF Montezzi, DE Xavier, RC Pico
    Journal of Global Antimicrobial Resistance 29, 207-211 2022
    Citations: 8