The Ferric Citrate Uptake System Encoded in a Novel - and -Harboring Conjugative Plasmid Contributes to the Virulence of .

is one major cause of bacterial infections and can horizontally acquire antimicrobial resistance and virulence genes through conjugation. Because conjugative plasmids can rapidly spread among bacteria of different species, the plasmids carrying both antimicrobial resistance and virulence genes may pose a significant threat to public health. Therefore, the identification and characterization of these plasmids may facilitate a better understanding of pathogenesis and the development of new strategies against infections.

Peptidoglycan Endopeptidase Spr of Uropathogenic Contributes to Kidney Infections and Competitive Fitness During Bladder Colonization.

Uropathogenic (UPEC) is the most common pathogen of urinary tract infections (UTIs). Antibiotic therapy is the conventional measure to manage such infections. However, the rapid emergence of antibiotic resistance has reduced the efficacy of antibiotic treatment.

Detection of Plasmid-Mediated β-Lactamase Genes and Emergence of a Novel AmpC (CMH-1) in at a Medical Center in Southern Taiwan.

The plasmid-mediated extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases in spp. have increasingly been reported. In this study, we investigated the prevalence of the plasmid-mediated β-lactamases in from bloodstream isolates at a medical center in southern Taiwan.

Klebsiella pneumoniae Isolates from Meningitis: Epidemiology, Virulence and Antibiotic Resistance.

Klebsiella pneumoniae (KP) resistance to broad-spectrum cephalosporin (BSC) in meningitis is important because of limited therapeutic options. To investigate the antibiotic resistance, virulence and epidemiology of KP in meningitis, we conducted a retrospective study for 33 non-metastatic isolates, including primary meningitis (n = 20) and post-craniotomy meningitis (n = 13) collected from 1999 to 2013. BSC resistance was found in 9 (27.

Comparison of synergism between colistin, fosfomycin and tigecycline against extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates or with carbapenem resistance.

Purpose: To investigate the synergistic and bactericidal effects of antimicrobial combinations of any two of colistin, fosfomycin and tigecycline against the nine extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae (KP) clinical isolates, including 4 carbapenem-susceptible strains and five imipenem and/or meropenem-resistant strains.

Methods: In vitro synergism and bactericidal activity of combination of colistin, fosfomycin and tigecycline were evaluated by time-kill studies in standard inoculum of bacterial densities of a suspension containing 5 × 10 CFU/mL by using 1/2× MIC for each alone, and both 1/2× and 1/4× MIC for any two drugs. The settings of low MIC dosing were allowed to rapidly survey the most active drug combination.

Impacts of Hypervirulence Determinants on Clinical Features and Outcomes of Bacteremia Caused by Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae.

We investigated the implications of hypervirulence determinants on clinical features of 48 adult patients with bacteremia caused by extended-spectrum β-lactamase-producing Klebsiella pneumoniae. Isolates in the hypervirulence group included any of the following virulence determinants: K1/K2 capsule serotypes, hypermucoviscosity phenotype, rmpA gene, or rmpA2 gene. Nonhypervirulence group isolates were negative for all of the above virulence factors.

In Vitro Activity of Imipenem and Colistin against a Carbapenem-Resistant Klebsiella pneumoniae Isolate Coproducing SHV-31, CMY-2, and DHA-1.

We investigated the synergism of colistin and imipenem against a multidrug-resistant K. pneumoniae isolate which was recovered from a severe hip infection. PCR and DNA sequencing were used to characterize the outer membrane porin genes and the resistance genes mediating the common β-lactamases and carbapenemases.

Intrapersonal mutation of rmpA and rmpA2: A reason for negative hypermucoviscosity phenotype and low virulence of rmpA-positive Klebsiella pneumoniae isolates.

Two Klebsiella pneumoniae isolates were simultaneously recovered from blood and urine cultures of the same patient. Both isolates were identical in genomic pulsotype by pulsed-field gel electrophoresis (PFGE). However, the hypermucoviscosity phenotype was confirmed in the blood strain but not the urine strain.

Low prevalence of rmpA and high tendency of rmpA mutation correspond to low virulence of extended spectrum β-lactamase-producing Klebsiella pneumoniae isolates.

Invasive syndrome caused by Klebsiella pneumoniae (KP), including liver abscess, is mainly caused by community-acquired strains with characteristics of positive hypermucoviscosity (HV) phenotype and regulator of mucoid phenotype A (rmpA) and transcriptional activator (rmpA2) genes. Extended- spectrum β-lactamase-producing KP (ESBL-KP) is commonly nosocomial and rarely HV-positive. We aimed to explore the reasons of the rarer prevalence of HV phenotype, rmpA and rmpA2 as well as the virulence phenotype among the ESBL-KP isolates from clinical specimens than those non-ESBL isolates.

The impact of inadequate terminal disinfection on an outbreak of imipenem-resistant Acinetobacter baumannii in an intensive care unit.

Background: This study was conducted to investigate an outbreak caused by imipenem-resistant Acinetobacter baumannii (IRAB) in a medical intensive care unit (ICU) in a regional hospital.

Methods: In response to an IRAB outbreak from October 2012 to February 2013, we developed several infection control measures, including an extensive review process of environmental cleaning and disinfection, and used molecular methods to identify each clinical and environmental IRAB isolate.

Results: During this five-month period, 22 patients were colonized with IRAB and 18 patients had IRAB infections.

In vitro activity of colistin sulfate against Enterobacteriaceae producing extended-spectrum β-lactamases.

The widespread multidrug-resistant Enterobacteriaceae pose a serious therapeutic challenge. Colistin and tigecycline are potential antimicrobial agents for treating infections caused by extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. We evaluated the in-vitro activity of colistin sulfate against 253 ESBL producers isolated from patients admitted to a medical center in southern Taiwan (Escherichia coli, n = 82; Klebsiella pneumoniae, n = 102; Enterobacter cloacae, n = 34; and Serratia marcescens, n = 35).

Prototheca algaemia: a rare but fatal opportunistic infection among immunocompromised individuals.

Infections due to Prototheca spp. are ubiquitous in nature, occurring in both immunocompetent and immunocompromised patients. The study cohort consisted of 14 cases of Prototheca algaemia reported over the past 5 decades and 2 recent cases from study hospitals.

A fish-stunning wound infection with acute cardiac injury.

Vibrio vulnificus typically causes septicemia and necrotic wound infection. Among V vulnificus–related complications, acute nonthrombotic myocardial damage has not been reported. The most effective antibiotic treatment of V vulnificus infection includes combination of a third-generation cephalosporin and a tetracycline or its analogue.

Bacteremia due to extended-spectrum-β-lactamase-producing Aeromonas spp. at a medical center in Southern Taiwan.

Although extended-spectrum-β-lactamase (ESBL)-producing aeromonads have been increasingly reported in recent years, most of them were isolates from case reports or environmental isolates. To investigate the prevalence of ESBL producers among Aeromonas blood isolates and the genes encoding ESBLs, consecutive nonduplicate Aeromonas blood isolates collected at a medical center in southern Taiwan from March 2004 to December 2008 were studied. The ESBL phenotypes were examined by clavulanate combination disk test and the cefepime-clavulanate ESBL Etest.

Use of inverse PCR for analysis of class 1 integrons carrying an unusual 3' conserved segment structure.

By using inverse PCR and DNA sequencing, 13 sul3-associated mutational integrons, 2 defective class 1 integrons, and 1 qnrB2-associated complex sul1-type class 1 integrons were identified in Salmonella enterica serovar Choleraesuis, Pseudomonas aeruginosa, and Enterobacter cloacae, respectively. In addition, conjugation and Southern hybridization demonstrated that unusual class 1 integrons were located on plasmids or integrated into chromosomal DNA. Thus, an inverse PCR assay can be a valuable tool for the analysis of unusual structures of the 3' conserved region of class 1 integrons.

One-tube loop-mediated isothermal amplification combined with restriction endonuclease digestion and ELISA for colorimetric detection of resistance to isoniazid, ethambutol and streptomycin in Mycobacterium tuberculosis isolates.

In this study, we designed a simple and rapid colorimetric detection method, a one-tube loop-mediated isothermal amplification (LAMP)-PCR-hybridization-restriction endonuclease-ELISA [one-tube LAMP-PCR-HY-RE-ELISA] system, to detect resistance to isoniazid, ethambutol and streptomycin in strains of Mycobacterium tuberculosis isolated from clinical specimens. The clinical performance of this method for detecting isoniazid-resistant, ethambutol-resistant and streptomycin-resistant isolates of M. tuberculosis showed 98.

Involvement of the residues of GSKIP, AxinGID, and FRATtide in their binding with GSK3beta to unravel a novel C-terminal scaffold-binding region.

The specificity and regulation of GSK3beta are thought to involve in the docking interactions at core kinase domain because of the particular amino acid residues. Recent X-ray diffraction studies illuminated the relative binding residues on AxinGID and FRATtide for GSK3beta docking and appeared that GSK3beta Val267Gly (V267G) and Tyr288Phe (Y288F) could distinguish the direct interaction between AxinGID and FRATtide. In order to explore the mode that involved the binding of GSKIP to GSK3beta and compare it with that of AxinGID and FRATtide, we pinpointed the binding sites of GSKIP to GSK3beta through the single-point mutation of four corresponding sites within GSK3beta (residues 260-300) as scaffold-binding region I (designated SBR-I(260-300)).

Extracts from Cladiella australis, Clavularia viridis and Klyxum simplex (soft corals) are capable of inhibiting the growth of human oral squamous cell carcinoma cells.

Many biomedical products have already been obtained from marine organisms. In order to search more therapeutic drugs against cancer, this study demonstrates the cytotoxicity effects of Cladiella australis, Clavularia viridis and Klyxum simplex extracts on human oral squamous cell carcinoma (SCC4, SCC9 and SCC25) cells using cell adhesion and cell viability assay. The morphological alterations in SCCs cells after treatment with three extracts, such as typical nuclear condensation, nuclear fragmentation and apoptotic bodies of cells were demonstrated by Hoechst stain.

Molecular characterisation of class 1 integrons in Salmonella enterica serovar Choleraesuis isolates from southern Taiwan.

Integron-mediated multidrug resistance in Salmonellaenterica serovar Choleraesuis poses a major concern in human salmonellosis in Taiwan. In this study, 71 strains of S. Choleraesuis harbouring a class 1 integron from humans and animals were characterised for detection of integrons, gene cassettes and the spvC virulence gene using molecular genetic techniques.

Evaluation of reverse transcription loop-mediated isothermal amplification in conjunction with ELISA-hybridization assay for molecular detection of Mycobacterium tuberculosis.

Traditional culture, followed by a panel of biochemical tests for the diagnosis of tuberculosis (TB), is time-consuming, and rapid identification of Mycobacterium tuberculosis is crucial for the early administration of appropriate therapy. In this study, the reverse transcription loop-mediated isothermal amplification combined with enzyme-linked immunosorbent hybridization (RT-LAMP-ELISA-hybridization) assay has been designed for the rapid detection of 16S rRNA in clinical isolates of M. tuberculosis.

Molecular diversity of class 1 integrons in human isolates of Aeromonas spp. from southern Taiwan.

This work studies antimicrobial resistance and class 1 integrons of Aeromonas spp. in human isolates from southern Taiwan. PCR amplification and DNA sequence analyses were performed to characterize the gene cassette regions of the class 1 integron in 204 isolates of Aeromonas hydrophila, 36 isolates of A.

Molecular characterisation of the metallo-beta-lactamase genes in imipenem-resistant Gram-negative bacteria from a university hospital in southern Taiwan.

In this study, 260 non-replicate imipenem-resistant Gram-negative bacteria isolated between January 2002 and December 2006 were subjected to a screening test for detection of metallo-beta-lactamase (MBL) using the Etest containing imipenem and ethylene diamine tetra-acetic acid (EDTA). Among the 260 strains, 123 (47.3%) appeared to produce MBL.

Characterization of class 1 integrons and antimicrobial resistance in CTX-M-3-producing Serratia marcescens isolates from southern Taiwan.

The objective of this study was to characterize the gene cassettes of class 1 integrons and antimicrobial resistance among CTX-M-3-producing Serratia marcescens isolates from different specimens in southern Taiwan. One hundred and twenty-two isolates (70.5%) of 173 CTX-M-3-producing S.