Publications by authors named "Willames M B S Martins"

Carbapenem-resistant Klebsiella pneumoniae is a common cause of healthcare-related infections, and it is widespread in hospitals and diverse environments with potentially serious public health implications. Herein, we have reported the isolation and characterization of an environmental Brazilian Klebsiella carbapenemase (BKC-1)-producing K. pneumoniae strain (IEC1205) isolated in 2018 from a river in the Amazon region, Brazil.

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Bacteriophages (phages) are viruses considered to be natural bacterial predators and widely detected in aquatic environments. Sewage samples are an important source of phage isolation since high density and diversity of bacterial cells are present, due to human, animal and household fluids. This study aims to investigate and characterise phages against an extremely drug-resistant (XDR) lineage, Klebsiella pneumoniae ST16, using sewage samples from different parts of the World.

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This study aimed to verify the role of IS in the expression and mobilization of and . Five constructs related to the natural genetic background in plasmid p60136 were made and submitted for antimicrobial susceptibility testing and quantitative reverse transcription-PCR. Transposition of IS was investigated using transposition assays involving a 9.

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Objective: To describe the undetected circulation of an epidemic BKC-1-producing Klebsiella pneumoniae ST442 clone, occasioning the first reported outbreak of the infrequent carbapenemase BKC-1.

Methods: Six hundred and forty-seven K. pneumoniae isolates (2008-2017) with reduced susceptibility to carbapenems were screened for bla.

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Bacteriophages are the most abundant organisms on Earth. As there are few effective treatment options against some pathogens, the interest in the bacteriophage control of multi-drug-resistant bacterial pathogens is escalating, especially for . This study aimed to develop a phage-based solution to the rising incidence of extensively drug-resistant clinical sequence type (ST16) infections starting from a set of phages recently characterized against this lineage.

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In the major human pathogen Klebsiella pneumoniae, MgrB inactivation by disruptive insertion sequence (IS) elements and mutations leading to early termination are known to play an important role in polymyxin resistance. In this study, we examined a collection of invasive -producing K. pneumoniae isolates belonging to the high-risk clone sequence type 258 (ST258) displaying high rates of resistance to many antimicrobials, including polymyxins.

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We sequenced 13 Neisseria gonorrhoeae isolates exhibiting distinct susceptibility profiles and which were recovered over 12 years in the metropolitan region of São Paulo, Brazil. Whole Genome Sequencing (WGS) was performed on an Illumina MiSeq™ 2 × 300 bp paired-end reads. Bioinformatics analyses were carried out using CGE, PATRIC, and BLAST databases for manual curation of obtained genomes.

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Geezett was isolated from hospital sewage in Hangzhou, China, and exhibits lytic activity against clinical isolates of the nosocomial pathogen Klebsiella pneumoniae. The bacteriophage is a myovirus and has a double-stranded DNA (dsDNA) genome 50,707 bp long, containing 79 open reading frames (ORFs).

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The recent emergence of mobile-tigecycline resistance tet(X) genes in human and animals in China seriously threats the clinical utility of tigecycline. Here we focused on the isolation and molecular characterization of plasmid-mediated tigecycline resistance tet(X4)-positive E. coli from different sources in Pakistan using MinION and Illumina sequencing.

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Objectives: Carbapenem resistance in Klebsiella pneumoniae is a major clinical challenge. Aminoglycosides remain an important asset in the current therapeutic arsenal to treat these infections. We examined aminoglycoside resistance phenotypes and genomics in a collection of 100 invasive KPC-producing K.

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We characterized a multidrug-resistant (MDR) spp. isolate highlighting the genetic aspects of the antimicrobial resistance genes. An spp.

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This study provides the genomic characterization and clinical description of bloodstream infections (BSI) cases due to ST15 KPC-2 producer Six KPC- isolates were recovered in 2015 in a tertiary Brazilian hospital and were analyzed by whole-genome sequencing (WGS) (Illumina MiSeq short reads). Of these, two isolates were further analyzed by Nanopore MinION sequencing, allowing complete chromosome and plasmid circularization (hybrid assembly), using Unicycler software. The clinical analysis showed that the 30-day overall mortality for these BSI cases was high (83%).

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We characterized by whole-genome sequencing (WGS) six carbapenem-resistant strains isolated from a Brazilian tertiary hospital during a 14-day period. The IS- structure was found in the chromosome of five isolates, whereas was inserted in a 16.6-kb plasmid in two isolates.

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Due to the emergence of multi-drug resistant bacteria, and the evident limitation in therapeutic options, alternatives to combat bacterial infections have been sought. One of these is phage therapy, which is the use of bacterial viruses to kill pathogenic bacteria responsible for the infection. These viruses called bacteriophages are very abundant organisms in the world and are harmless to humans.

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Carbapenem resistance in Acinetobacter baumannii is a public health issue globally, mainly due to the production of carbapenem hydrolyzing class D β-lactamases (CHDLs). In Brazil, OXA-23 and OXA-143 CHDLs have been prevalent in A. baumannii from clinical settings, with some OXA-23 reports in the environmental samples, whereas OXA-72 has begun to be increasingly reported.

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We characterize by whole-plasmid-sequence (WPS) two-plasmid-borne obtained from (Asp-1069) and (Acb-45063) clinical strains recovered 17 years apart from distinct Brazilian regions. Multilocus sequence type (MLST) analysis showed that the Asp-1069 and Acb-45063 strains belong to ST551 and ST15/CC15, respectively. WPS analysis demonstrated that was located in two distinct plasmids named pAs1069_a (24,672 bp/44 open reading frames [ORFs]) and pAb45063_b (19,808 bp/24 ORFs), which belong to the GR8/GR23 () and GR4 () incompatibility groups, respectively.

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Article Synopsis
  • The article reports on a study involving 29 adult patients with infections caused by carbapenem and polymyxin-resistant bacteria who were treated with ceftazidime/avibactam (CAZ-AVI) under a compassionate-use protocol.
  • The results showed a high clinical success rate of 82.7%, with notable effectiveness even in cases of bacteremia (75%).
  • However, the mortality rates were concerning, with 31% at 14 days and 51.7% at 30 days, particularly high among patients with renal impairment.
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Nine carbapenem-resistant Acinetobacter baumannii isolates carrying bla and an ISAba1 upstream occAB1 were evaluated. They were clonally related and belonged to ST107. An OXA-143-producing A.

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The production of São Paulo metallo-β-lactamase (SPM-1) is the most common carbapenem resistance mechanism detected among multidrug-resistant Pseudomonas aeruginosa clinical isolates in Brazil. Dissemination of SPM-1-producing P. aeruginosa has been restricted to the nosocomial settings, with sporadic reports of environmental isolates due to contamination by hospital sewage.

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The emergence and rapid dissemination of colistin-resistant carrying the plasmid-mediated gene have created an urgent need to develop specific screening methods. In this study, we evaluated four assays based on the inhibition of MCR-1 activity by EDTA: (i) a combined-disk test (CDT) comparing the inhibition zones of colistin and colistin (10 μg) plus EDTA (100 mM); (ii) reduction of colistin MIC (CMR) in the presence of EDTA (80 μg/ml); (iii) a modified rapid polymyxin Nordmann/Poirel test (MPNP); and (iv) alteration of zeta potential (R = ZP/ZP). We obtained encouraging results for the detection of MCR-1 in isolates recovered from human, food, and animal samples, using the following assay parameters: ≥3 mm difference in the inhibition zones between colistin disks without and with EDTA; ≥4-fold colistin MIC decrease in the presence of EDTA; R of ≥2.

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Carbapenems represent the mainstay therapy for the treatment of serious infections. However, the emergence of carbapenem resistance has jeopardized the clinical use of this important class of compounds. The production of SPM-1 metallo-β-lactamase has been the most common mechanism of carbapenem resistance identified in isolated from Brazilian medical centers.

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Background: The emergence of multidrug-resistant Klebsiella pneumoniae is a major public health concern. Many K. pneumoniae infections can only be treated when resorting to last-line drugs such as polymyxin B (PB).

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