Molecular epidemiological analyses of isolates in a university hospital in Japan.

Background: We performed molecular epidemiological analyses of isolates in a university hospital in Japan to reveal the risk of infection.

Methods: Cultured isolates from 919 stool samples from 869 patients obtained from July 2015 to August 2016 were subjected to toxin gene detection, ribotyping, multilocus sequence typing, antimicrobial susceptibility testing, and quantitative real-time polymerase chain reaction testing for toxin gene expression.

Results: Of the 919 stool samples from 869 patients, was isolated from 153 samples (16.

Enterococcal Linear Plasmids Adapt to Enterococcus faecium and Spread within Multidrug-Resistant Clades.

Antimicrobial resistance (AMR) of bacterial pathogens, including enterococci, is a global concern, and plasmids are crucial for spreading and maintaining AMR genes. Plasmids with linear topology were identified recently in clinical multidrug-resistant enterococci. The enterococcal linear-form plasmids, such as pELF1, confer resistance to clinically important antimicrobials, including vancomycin; however, little information exists about their epidemiological and physiological effects.

Adsorption of extracellular proteases and pyocyanin produced by using a macroporous magnesium oxide-templated carbon decreases cytotoxicity.

is one of the most common pathogens isolated in clinical settings and produces a wide range of extracellular molecules that contributes to the virulence. Chemotherapy options to prevent and treat infections are limited because this pathogen is highly and innately resistant to some classes of conventional drugs. Alternative methods to conquer , including multidrug resistant strains, are being investigated.

Elucidation of host diversity of the VanD-carrying genomic islands in enterococci and anaerobes.

Background: VanD is a rare type of vancomycin resistance worldwide. However, the host diversity of the gene cluster and the structural similarity of their genomic islands are not well understood.

Methods: Three VanD-type strains (AA620, AA622 and AA624) isolated from a Japanese patient who underwent vancomycin treatment in 2017 were analysed.

Adsorption of Phenazines Produced by Using AST-120 Decreases Pyocyanin-Associated Cytotoxicity.

AST-120 (Kremezin) is used to treat progressive chronic kidney disease by adsorbing uremic toxin precursors produced by the gut microbiota, such as indole and phenols. Previously, we found that AST-120 decreased drug tolerance and virulence in by adsorbing indole. Here, we show that AST-120 adsorbs phenazine compounds, such as pyocyanin, produced by including multidrug-resistant strains, and suppresses pyocyanin-associated toxicity in A-549 (alveolar adenocarcinoma) and Caco-2 (colon adenocarcinoma) cells.

Isolation of Serratia fonticola Producing FONA, a Minor Extended-Spectrum β-Lactamase (ESBL), from Imported Chicken Meat in Japan.

Five novel strains of Serratia fonticola that produce FONA, a minor extended-spectrum beta-lactamase (ESBL), were isolated during routine surveillance of ESBL-producing Enterobacteriaceae in imported chicken meat in Japan in 2017 and 2018. These strains exhibited a clear ESBL phenotype in susceptibility tests carried out in the presence of clavulanic acid; however, all strains tested negative in a multiplex polymerase chain reaction assay used to detect TEM, SHV, and CTX-M β-lactamase genes. After identification of the bacterial species as S.

Effect of Sub-MICs of Macrolides on the Sensitivity of Pseudomonas aeruginosa to Nitrosative Stress: Effectiveness against P. aeruginosa with and without Multidrug Resistance.

Sub-MICs of the 14-membered macrolides erythromycin (EM) and clarithromycin (CAM) decreased the growth of PAO1 and increased its sensitivity to endogenous and exogenous nitrosative stress. However, a 16-membered macrolide, josamycin (JM), was not or less effective. In 9 of 13 non-multidrug-resistant (non-MDRP) and 9 of 27 MDRP ST235 strains, the sub-MIC of EM induced significant reductions in bacterial numbers following treatment with a nitric oxide donor.

Isolation of thymidine-dependent and extended-spectrum-β-lactamase-producing Escherichia coli small-colony variant from urine of a septuagenarian female patient with recurrent cystitis: A case report with genetic investigation.

Thymidine-dependent small-colony variant (TD-SCV) of Escherichia coli was isolated from urine of a septuagenarian female patient on hemodialysis suffering from recurrent cystitis. The patient had been treated with frequent administrations of trimethoprim sulfamethoxazole (SXT), every time her cystitis symptoms developed. In the TD-SCV isolate, the deletion was detected in the thyA gene associated with thymidylate synthase.

Novel Multidrug-Resistant Enterococcal Mobile Linear Plasmid pELF1 Encoding and Gene Clusters From a Japanese Vancomycin-Resistant Enterococci Isolate.

Vancomycin-resistant enterococci are troublesome pathogens in clinical settings because of few treatment options. A VanA/VanM-type vancomycin-resistant clinical isolate was identified in Japan. This strain, named AA708, harbored five plasmids, one of which migrated during agarose gel electrophoresis without S1 nuclease treatment, which is indicative of a linear topology.

Dissemination and genetic analysis of the stealthy vanB gene clusters of Enterococcus faecium clinical isolates in Japan.

Background: VanB-type vancomycin (VAN) resistance gene clusters confer VAN resistances on Enterococcus spp. over a wide range of MIC levels (MIC = 4-1000 mg/L). However, the epidemiology and the molecular characteristics of the VAN susceptible VanB-type Enterococcus still remain unclear.

Oxygen Limitation Enhances the Antimicrobial Activity of Fosfomycin in Following Overexpression of Which Encodes Glycerol-3-Phosphate/Fosfomycin Symporter.

Fosfomycin is resurfacing as a "last resort drug" to treat infections caused by multidrug resistant pathogens. This drug has a remarkable benefit in that its activity increases under oxygen-limited conditions unlike other commonly used antimicrobials such as β-lactams, fluoroquinolones and aminoglycosides. Especially, utility of fosfomycin has being evaluated with particular interest to treat chronic biofilm infections caused by because it often encounters anaerobic situations.

First case report of bacteremia caused by Dysgonomonas mossii.

We here report a case of Dysgonomonas mossii bacteremia with cholangitis. An 85-year-old male patient with recurrent hepatitis B surface antigen-negative/anti-hepatitis C virus-negative hepatocellular carcinoma came to our hospital in poor physical condition. Two sets of blood cultures revealed a positive result for D.

Membrane-active antimicrobial poly(amino-modified alkyl) β-cyclodextrins synthesized click reactions.

The emergence of drug-resistant bacteria has led to the high demand for new antibiotics. In this report, we investigated membrane-active antimicrobial β-cyclodextrins. These contain seven amino-modified alkyl groups on a molecule, which act as functional moieties to permeabilize bacterial cell membranes.

Genetic shifts in methicillin-resistant Staphylococcus aureus epidemic clones and toxin gene profiles in Japan: comparative analysis among pre-epidemic, epidemic and post-epidemic phases.

Purpose: The decline in methicillin-resistant Staphylococcus aureus (MRSA) isolation rates has become a general observation worldwide, including Japan. We hypothesized that some genetic shift in MRSA might cause this phenomenon, and therefore we investigated the genetic profiles among MRSA clinical isolates obtained from three different epidemic phases in Japan.

Methodology: A total of 353 MRSA isolates were selected from 202 medical facilities in 1990 (pre-epidemic phase), 2004 (epidemic phase) and 2016 (post-epidemic phase).

New colony multiplex PCR assays for the detection and discrimination of vancomycin-resistant enterococcal species.

New colony multiplex PCR assays for detection of seven types of vancomycin-resistance determinants and eight types of Enterococcus species were developed. For 135 enterococcal isolates examined in this study, these assays showed high sensitivity and specificity, and could provide the rapid and accurate detection of vancomycin-resistant determinants and Enterococcus spp.

Cooperative Actions of CRP-cAMP and FNR Increase the Fosfomycin Susceptibility of Enterohaemorrhagic (EHEC) by Elevating the Expression of and under Anaerobic Conditions.

Bacterial infections to anaerobic site are often hard to be treated because the activity of most of antimicrobials decreases under anaerobic conditions. However, fosfomycin rather provides a greater activity under anaerobic conditions than aerobic conditions. Previously, we found that expression of and , fosfomycin symporters in enterohaemorrhagic (EHEC) was upregulated by FNR, a global regulator during the anaerobiosis of the bacterium, which led to increased uptake and susceptibility to this drug.

Elevated Expression of GlpT and UhpT via FNR Activation Contributes to Increased Fosfomycin Susceptibility in Escherichia coli under Anaerobic Conditions.

Because a shortage of new antimicrobial agents is a critical issue at present, and with the spread of multidrug-resistant (MDR) pathogens, the use of fosfomycin to treat infections is being revisited as a "last-resort option." This drug offers a particular benefit in that it is more effective against bacteria growing under oxygen-limited conditions, unlike other commonly used antimicrobials, such as fluoroquinolones and aminoglycosides. In this study, we showed that Escherichia coli strains, including enterohemorrhagic E.

Identification of a second two-component signal transduction system that controls fosfomycin tolerance and glycerol-3-phosphate uptake.

Particular interest in fosfomycin has resurfaced because it is a highly beneficial antibiotic for the treatment of refractory infectious diseases caused by pathogens that are resistant to other commonly used antibiotics. The biological cost to cells of resistance to fosfomycin because of chromosomal mutation is high. We previously found that a bacterial two-component system, CpxAR, induces fosfomycin tolerance in enterohemorrhagic Escherichia coli (EHEC) O157:H7.

Nosocomial infection caused by vancomycin-susceptible multidrug-resistant Enterococcus faecalis over a long period in a university hospital in Japan.

Compared with other developed countries, vancomycin-resistant enterococci (VRE) are not widespread in clinical environments in Japan. There have been no VRE outbreaks and only a few VRE strains have sporadically been isolated in our university hospital in Gunma, Japan. To examine the drug susceptibility of Enterococcus faecalis and nosocomial infection caused by non-VRE strains, a retrospective surveillance was conducted in our university hospital.

Role of the CpxAR two-component signal transduction system in control of fosfomycin resistance and carbon substrate uptake.

Although fosfomycin is an old antibiotic, it has resurfaced with particular interest. The antibiotic is still effective against many pathogens that are resistant to other commonly used antibiotics. We have found that fosfomycin resistance of enterohemorrhagic Escherichia coli (EHEC) O157:H7 is controlled by the bacterial two-component signal transduction system CpxAR.

Identification of novel genes responsible for overexpression of ampC in Pseudomonas aeruginosa PAO1.

The development of resistance to antipseudomonal penicillins and cephalosporins mediated by the chromosomal ampC gene in Pseudomonas aeruginosa is of clinical importance. We isolated piperacillin-resistant mutants derived from P. aeruginosa PAO1 and analyzed two mutants that had an insertion in mpl and nuoN.

Stenotrophomonas maltophilia strains isolated from a university hospital in Japan: genomic variability and antibiotic resistance.

The diversity within the genetic and antibiotic resistance profiles and the production of virulence-associated enzymic activities of 66 Stenotrophomonas maltophilia strains collected from a university hospital in Japan in 2005 were studied. PFGE analysis of the collection indicated that a variety of profiles were present. MLST analysis of nine selected strains showed that four of the six sequence types identified were novel.

Identification of VanN-type vancomycin resistance in an Enterococcus faecium isolate from chicken meat in Japan.

Five VanN-type vancomycin-resistant Enterococcus faecium strains were isolated from a sample of domestic chicken meat in Japan. All isolates showed low-level resistance to vancomycin (MIC, 12 mg/liter) and had the same pulsed-field gel electrophoresis profile. The vancomycin resistance was encoded on a large plasmid (160 kbp) and was expressed constitutively.