Publications by authors named "Vignaroli C"

The presence of erm(T) gene conferring resistance to macrolides, lincosamides and streptogramin B (MLS), was screened in 296 enterococci collected from clinical samples in a central Italy hospital and seven Enterococcus faecium isolates resulted positive to erm(T) by PCR. All isolates were resistant to erythromycin, tetracycline, ciprofloxacin and ampicillin but susceptible to vancomycin and chloramphenicol. Whole Genome Sequencing analysis revealed that in five E.

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After harvesting of cones used for beer production, the remaining hop vegetative biomass requires disposal. The hop plant contains bioactive compounds in all its parts-cones, leaves, and roots-exhibiting interesting antioxidant, antiviral, and antibacterial properties. In this work, extracts obtained from hop leaves, a plant material often neglected in the hop cultivation, have been investigated; the qualitative UHPLC-MS/MS and GC-TOF-MS characterization revealed the presence of bioactive compounds such as polyphenols, α- and β-acids and terpenes are present.

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Article Synopsis
  • In patients with Cystic Fibrosis (pwCF), lung infections can be tricky to treat because some bacteria are in a "sleeping" state called VBNC, which makes them hard to find using regular tests.
  • A study looked at 94 pwCF over a year to see how often these VBNC bacteria were present and how it related to their health.
  • The results showed that most patients had VBNC cells at least once, and these were linked to worse lung health and more frequent flare-ups in their condition, highlighting the need for better testing methods.
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Objectives: Staphylococcus epidermidis is a member of the human skin microbiome. However, in recent decades, multidrug-resistant and hospital-adapted S. epidermidis clones are increasingly involved in severe human infections associated with medical devices and in immunocompromised patients.

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Purpose: To investigate the occurrence of vancomycin-variable enterococci (VVE) in a hospital in central Italy.

Methods: vanA positive but vancomycin-susceptible Enterococcus faecium isolates (VVE-S) were characterized by antibiotic susceptibility tests, molecular typing (PFGE and MLST), and WGS approach. The reversion of VVE-S to a resistant phenotype was assessed by exposure to increasing vancomycin concentrations, and the revertant isolates were used in filter mating experiments.

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The MexXY-OprM multidrug efflux pump (EP) in aminoglycosides resistant Pseudomonas aeruginosa is one of the major resistance mechanisms, which is often overexpressed in strains isolated from pulmonary chronic disease such as cystic fibrosis. In this research, we focused on the design of potential efflux pumps inhibitors, targeting MexY, the inner membrane component, in an allosteric site. Berberine has been considered as lead molecule since we previously demonstrated its effectiveness in targeting MexY in laboratory reference strains.

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  • * Researchers analyzed 191 samples from different pig farms, using culture methods to isolate carbapenemase-producing Enterobacteriaceae (CPE) and assess their resistance levels.
  • * Findings revealed only one resistant strain, Aeromonas veronii, with high resistance levels, and a low prevalence of certain resistance genes, highlighting the need for monitoring these bacteria in livestock to safeguard human health.
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To investigate the occurrence of oxazolidinone resistance genes, 18 florfenicol-resistant enterococci were isolated from 66 fecal samples collected from several cattle farms in central Italy. The PCR screening indicated that only a bovine florfenicol-resistant isolate, 249031-C, was positive for the presence of and genes. The strain was tested for its susceptibility to florfenicol, chloramphenicol, linezolid, tedizolid, tetracycline, erythromycin, and vancomycin.

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Persistent and viable but non-culturable (VBNC) cells are mainly responsible for the recurrence and non-responsiveness to antibiotics of cystic fibrosis (CF) lung infections. The sub-inhibitory antibiotic concentrations found in the CF lung in between successive therapeutic cycles can trigger the entry into the VBNC state, albeit with a strain-specific pattern. Here, we analyzed the VBNC cell induction in the biofilms of two CF isolates, exposed to starvation with/without antibiotics, and investigated the putative genetic determinants involved.

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Oxazolidinones are critically important antibiotics to treat human infections caused by multidrug-resistant bacteria, therefore the occurrence of linezolid-resistant enterococci from food-producing animals poses a serious risk to human health. In this study, Enterococcus avium 38157 and 44917 strains, isolated from the brain of two unrelated piglets, were found to carry the linezolid resistance genes cfr(D)-optrA, and cfr(D2)-poxtA, respectively. Whole genome sequencing analysis of E.

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Background: The presence of carbapenemase-producing bacteria (CPB) in animal hosts and along the food chain may result in the development of reservoirs for human infections. Several CPB strains isolated from animals have been reported, suggesting that transmission and dissemination of the corresponding genes between humans and animals may occur. Animal and food samples have complex backgrounds that hinder the detection of CPB present in low concentrations by standard detection procedures.

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The recovery and characterization of a multidrug-resistant, KPC-3-producing Klebsiella michiganensis that was obtained from Venus clam samples is reported in this study. A whole-genome sequencing (WGS) analysis using Illumina and Nanopore technologies of the 23999A2 isolate revealed that the strain belonged to the new sequence type 382 (ST382) and carried seven plasmid replicon sequences, including four IncF type plasmids (FII, FIIY, FIIk, and FIB), one IncHI1 plasmid, and two Col plasmids. The FIB and FII plasmids showed high homology to each other and to multireplicon pKpQIL-like plasmids that are found in epidemic KPC-K.

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Antimicrobial resistance (AMR) represents a global health issue threatening our social lifestyle and the world economy. Efflux pumps are widely involved in AMR by playing a primary role in the development of specific mechanisms of resistance. In addition, they seem to be involved in the process of biofilm formation and maintenance, contributing to enhance the risk of creating superbugs difficult to treat.

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This study shows that Escherichia coli can be temporarily enriched in zooplankton under natural conditions and that these bacteria can belong to different phylogroups and sequence types (STs), including environmental, clinical, and animal isolates. We isolated 10 E. coli strains and sequenced the genomes of two of them.

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Objectives: To characterize a linezolid-resistant Enterococcus gallinarum isolate of porcine origin co-carrying cfr, optrA and poxtA genes.

Methods: The genome was sequenced using the Illumina and Nanopore platforms. The presence of circular intermediates was examined by inverse PCR.

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Objectives: To investigate the genetic elements and the transferability of linezolid resistance genes in three enterococci co-carrying cfr(D) and poxtA2 isolates from manure of a swine farm in central Italy.

Methods: Two Enterococcus faecalis isolates and one Enterococcus casseliflavus isolate carrying both cfr(D) and poxtA genes were tested for their susceptibility to florfenicol, chloramphenicol, linezolid, tedizolid, tetracycline and vancomycin. Linezolid resistance genes transfer (filter mating), localization (S1-PFGE/hybridization), genetic elements and relatedness between isolates (WGS) were analysed.

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The water intake of a drinking water treatment plant (DWTP) in Central Italy was monitored over six bloom seasons for cyanotoxin severity, which supplies drinking water from an oligo-mesotrophic lake with microcystin levels up to 10.3 μg/L. The historical data showed that the water temperature did not show extreme/large seasonal variation and it was not correlated either with cyanobacterial growth or microcystin concentration.

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We report a novel IncHI2 plasmid coharboring , two copies of , and resistance genes in a human Escherichia coli isolate of the new serogroup O188. The gene was included in a class 1 integron, in a cassette bracketed by IS and ΔIS1R, and in two copies within a new composite Tn-like transposon. The emergence of carbapenem and colistin resistance genes in a single plasmid is of great concern for upcoming clinical therapies.

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Linezolid is a last-resort antibiotic for the treatment of severe infections caused by multidrug-resistant Gram-positive organisms; although linezolid resistance remains uncommon, the number of linezolid-resistant enterococci has increased in recent years due to worldwide spread of acquired resistance genes (, , and ) in clinical, animal, and environmental settings. In this study, we investigated the occurrence of linezolid-resistant enterococci in marine samples from two coastal areas in Italy. Isolates grown on florfenicol-supplemented Slanetz-Bartley agar plates were investigated for their carriage of , , and genes; was found in one isolate, was found in three isolates and two isolates, and was not found.

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A retrospective study of the epidemiology of vancomycin-resistant enterococci (VRE) in a regional hospital of central Italy in 2001-2018 demonstrated an increased VRE prevalence since 2016. A total of 113 VRE isolates, 89 E. faecium (VREfm) and 24 E.

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Aims: Extensively-drug-resistant Pseudomonas aeruginosa constitutes a serious threat to patients suffering from Cystic Fibrosis (CF). In these patients, P. aeruginosa lung infection is commonly treated with aminoglycosides, but treatments are largely unsuccessful due a variety of resistance mechanisms.

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Unlike human isolates, environmental isolates have not been thoroughly investigated for the diversity and transferability of antibiotic-resistant plasmids. In this study, antibiotic-resistant strains from marine sediment ( = 50) and clams ( = 53) were analyzed (i) for their plasmid content using a PCR-based plasmid replicon typing (PBRT) kit and (ii) for the transferability of plasmid-associated antibiotic resistance (AR) traits by mating experiments. Fifteen of the thirty replicons targeted by the PBRT kit were detected in the isolates; 8/15 were identified in both sediment and clam isolates, although at different frequencies.

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In this study, a drug discovery programme that sought to identify novel dual bacterial topoisomerase II inhibitors (NBTIs) led to the selection of six optimized compounds. In enzymatic assays, the molecules showed equivalent dual-targeting activity against the DNA gyrase and topoisomerase IV enzymes of Staphylococcus aureus and Escherichia coli. Consistently, the compounds demonstrated potent activity in susceptibility tests against various Gram-positive and Gram-negative reference species, including ciprofloxacin-resistant strains.

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