Publications by authors named "Roberta Ruedas Martins"
The immunosuppressive effect of methotrexate has rarely been associated with reactivation of cutaneous leishmaniasis. Here we present a case of a cutaneous leishmaniasis patient with atypical clinical symptoms without splenomegaly but with cutaneous manifestations after treatment of rheumatoid arthritis with methotrexate and blood recovery of the parasite. Next-generation sequencing was used to identify Leishmania infantum chagasi in the patient's blood sample.
View Article and Find Full Text PDFLeishmaniasis is a major public health problem worldwide. Although next generation sequencing technology has been widely used in the diagnosis of infectious diseases, it has been scarcely applied in identification of Leishmania species. The aim of this study was to compare the efficiency of MinION™ nanopore sequencing and polymerase chain reaction restriction fragment length polymorphism in identifying Leishmania species.
View Article and Find Full Text PDFConjugative transfer of plasmid p_8N_qac(MN687830.1) carrying qacA gene from Staphylococcus aureus to Escherichia coli C600: potential mechanism for spreading chlorhexidine resistance.
Rev Inst Med Trop Sao Paulo
December 2021
Article Synopsis
- The study investigates the transfer of a resistance gene, qacA, from methicillin-resistant Staphylococcus aureus (MRSA) to Escherichia coli C600 via conjugative plasmids, which is not well understood in Gram-positive to Gram-negative bacteria.* -
- Through experiments, they successfully showed that MRSA can transfer chlorhexidine resistance to E. coli, significantly increasing the latter's resistance levels after the transfer.* -
- This research represents the first documented instance of the specific plasmid p_8N_qac carrying qacA being transferred to E. coli, highlighting concerns about the spread of resistance genes and the need for better antiseptic use.*
Carbapenem-resistant colonization and infection is associated with lower overall survival in a cohort of haematopoietic stem-cell transplantation patients: mechanism of resistance and virulence by whole-genome sequencing.
J Med Microbiol
October 2021
Carbapenem-resistant (CRK) infections are a growing concern in immunocompromised patients. The aim of the present study was to evaluate the impact of CRK colonization and infection in overall mortality for haematopoietic stem-cell transplant (HSCT) patients. We also aimed to investigate resistance and virulence profiles of CRK isolates and assess their epidemiological and genetic relatedness.
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- - The study investigates the effectiveness of fosfomycin as a treatment against multi-resistant A. baumannii infections and aims to understand its resistance mechanisms by analyzing 32 bacterial isolates.
- - Results showed a wide range of fosfomycin susceptibility (MIC values from 32 to ≥256 mg/L), with specific resistance genes found in some isolates, including mutations in key metabolic pathways.
- - Key findings include the absence of fosA and fosB genes in all isolates, presence of the fosX gene in four, and notable mutations in the MurA enzyme and adenylate cyclase that may impact fosfomycin resistance mechanisms in A. baumannii.
Article Synopsis
- The study investigates the effectiveness of chlorhexidine (CHX) against methicillin-resistant Staphylococcus aureus (MRSA) in clinical isolates from a Brazilian hospital over a span of 11 years.
- A total of 216 MRSA isolates were analyzed for susceptibility to CHX and mupirocin, revealing resistance linked to specific genetic markers, including the qacA and mupA genes.
- The findings highlight the risk of spreading resistance to mupirocin within the hospital, emphasizing the need for ongoing monitoring and effective infection control measures.
Treatment of infections caused by A. baumannii is becoming a challenge due to the ability to develop multidrug-resistance, virulence, and high mortality. We described the colistin resistance and virulence genes present in sixA.
View Article and Find Full Text PDFSynergistic Effect of Ceftazidime-Avibactam with Meropenem against Panresistant, Carbapenemase-Harboring and Investigated Using Time-Kill and Disk Approximation Assays.
Antimicrob Agents Chemother
May 2019
Article Synopsis
- - The study assessed how effective ceftazidime-avibactam is alone and in combination with meropenem against 11 multi-drug resistant bacteria, particularly those with oxacillinases.
- - Results showed that ceftazidime-avibactam worked really well, especially when used with meropenem, against these resistant strains.
- - The disk approximation method used in the study effectively identified synergistic interactions in the treatment of infections.
Staphylococcus aureus (SA) is a commensal habitant of nasal cavities and skin. Colonization by community-acquired methicillin-resistant SA (CA-MRSA) is associated with infections in patients who have not been recently hospitalized. The aim of this study is to determine the prevalence of MRSA colonization in an outpatient population, currently unknown in Brazil.
View Article and Find Full Text PDFObjectives: Based on pulsed-field gel electrophoresis (PFGE) profile, whole-genome sequencing (WGS) of eight carbapenem-resistant Pseudomonas aeruginosa isolates from a bone marrow transplant unit in São Paulo, Brazil, was performed to investigate the presence of resistance and virulence genes as well as to determine the sequence type (ST) by multilocus sequence typing (MLST).
Methods: The initial phenotypic susceptibility pattern of the isolates was determined by VITEK2. Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method for amikacin, meropenem and colistin.
Multidrug-resistant Stenotrophomonas maltophilia: Description of new MLST profiles and resistance and virulence genes using whole-genome sequencing.
J Glob Antimicrob Resist
December 2018
Article Synopsis
- * Researchers sequenced the genomes of the isolates from three patients and discovered three new multilocus sequence typing (MLST) profiles that show different virulence and resistance characteristics.
- * The findings suggest that resistance to trimethoprim/sulfamethoxazole is linked to specific efflux pump genes, with implications for understanding how resistance develops in these bacteria.
Purpose: Carbapenem resistance in P. aeruginosa is increasing worldwide. In Brazil, SPM-1 is the main P.
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