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Sample records for ciprofloxacin resistant escherichia

  1. Ciprofloxacin-resistant Escherichia coli in Central Greece: mechanisms of resistance and molecular identification

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    Mavroidi Angeliki

    2012-12-01

    Full Text Available Abstract Background Fluoroquinolone resistant E. coli isolates, that are also resistant to other classes of antibiotics, is a significant challenge to antibiotic treatment and infection control policies. In Central Greece a significant increase of ciprofloxacin-resistant Escherichia coli has occurred during 2011, indicating the need for further analysis. Methods A total of 106 ciprofloxacin-resistant out of 505 E. coli isolates consecutively collected during an eight months period in a tertiary Greek hospital of Central Greece were studied. Antimicrobial susceptibility patterns and mechanisms of resistance to quinolones were assessed, whereas selected isolates were further characterized by multilocus sequence typing and β-lactamase content. Results Sequence analysis of the quinolone-resistance determining region of the gyrA and parC genes has revealed that 63% of the ciprofloxacin-resistant E. coli harbored a distinct amino acid substitution pattern (GyrA:S83L + D87N; ParC:S80I + E84V, while 34% and 3% carried the patterns GyrA:S83L + D87N; ParC:S80I and GyrA:S83L + D87N; ParC:S80I + E84G respectively. The aac (6’-1b-cr plasmid-mediated quinolone resistance determinant was also detected; none of the isolates was found to carry the qnrA, qnrB and qnrS. Genotyping of a subset of 35 selected ciprofloxacin-resistant E. coli by multilocus sequence typing has revealed the presence of nine sequence types; ST131 and ST410 were the most prevalent and were exclusively correlated with hospital and health care associated infections, while strains belonging to STs 393, 361 and 162 were associated with community acquired infections. The GyrA:S83L + D87N; ParC:S80I + E84V substitution pattern was found exclusively among ST131 ciprofloxacin-resistant E. coli. Extended-spectrum β-lactamase-positive ST131 ciprofloxacin-resistant isolates produced CTX-M-type enzymes; eight the CTX-M-15 and one the CTX-M-3 variant. CTX-M-1 like and KPC-2 enzymes were detected

  2. Urinary Tract Physiological Conditions Promote Ciprofloxacin Resistance in Low-Level-Quinolone-Resistant Escherichia coli.

    Science.gov (United States)

    Martín-Gutiérrez, Guillermo; Rodríguez-Beltrán, Jerónimo; Rodríguez-Martínez, José Manuel; Costas, Coloma; Aznar, Javier; Pascual, Álvaro; Blázquez, Jesús

    2016-07-01

    Escherichia coli isolates carrying chromosomally encoded low-level-quinolone-resistant (LLQR) determinants are frequently found in urinary tract infections (UTIs). LLQR mutations are considered the first step in the evolutionary pathway producing high-level fluoroquinolone resistance. Therefore, their evolution and dissemination might influence the outcome of fluoroquinolone treatments of UTI. Previous studies support the notion that low urine pH decreases susceptibility to ciprofloxacin (CIP) in E. coli However, the effect of the urinary tract physiological parameters on the activity of ciprofloxacin against LLQR E. coli strains has received little attention. We have studied the activity of ciprofloxacin under physiological urinary tract conditions against a set of well-characterized isogenic E. coli derivatives carrying the most prevalent chromosomal mutations (ΔmarR, gyrA-S83L, gyrA-D87N, and parC-S80R and some combinations). The results presented here demonstrate that all the LLQR strains studied became resistant to ciprofloxacin (according to CLSI guidelines) under physiological conditions whereas the control strain lacking LLQR mutations did not. Moreover, the survival of some LLQR E. coli variants increased up to 100-fold after challenge with a high concentration of ciprofloxacin under UTI conditions compared to the results seen with Mueller-Hinton broth. These selective conditions could explain the high prevalence of LLQR mutations in E. coli Furthermore, our data strongly suggest that recommended methods for MIC determination produce poor estimations of CIP activity against LLQR E. coli in UTIs. PMID:27139482

  3. Prevalence of Plasmid-Mediated Quinolone Resistance Genes among Ciprofloxacin-Nonsusceptible Escherichia coli and Klebsiella pneumoniae Isolated from Blood Cultures in Korea

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    Hee Young Yang

    2014-01-01

    Full Text Available OBJECTIVES:To analyze the prevalence of plasmid-mediated quinolone resistance (PMQR determinants in ciprofloxacin-nonsusceptible Escherichia coli and Klebsiella pneumoniae isolated from patients at a tertiary care hospital in Korea.

  4. Accumulation of ciprofloxacin and lomefloxacinin fluoroquinolone-resistant strains of Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    夏培元; 冯萍; 钟利; 吕晓菊; 雷秉钧

    2002-01-01

    Objective To evaluate the role of outer membrane protein (Omp) F-deficiency and active efflux in the accumulation of hydrophilic fluoroquinolones ciprofloxacin (CPLX) and lomefloxacin (LMLX) in resistant E. coli strains. Methods Fluoroquinolone accumulation in bacteria and the effect of active efflux were measured by a fluorescence method. The outer membrane proteins of the bacteria were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). E. coli strains in this study included control strains JF701 and JF703 that are OmpC- or OmpF-deficient mutants of E. coli K-12, respectively, and the fluoroquinolone susceptible strain the fluoroquinolone susceptible strain of Escherichia coli (Ecs) and its in vitroselected resistant strains R2 and R256, and the clinical resistant isolates R5 and R6. Results The steady-state accumulation concentration of each drug in Ecs appeared to be the same as in JF701, while in the OmpF- deficient strain JF703, it was 1/5 CPLX or 1/2 LMLX lower than that in JF701, but JF703 was still susceptible to fluoroquinolones. On the other hand, compared with susceptible strains, a 2- to 10-fold decrease in the accumulation of each drug was found in the resistant strains except R2, in which the accumulation was slightly higher than in JF703. After the addition of 2,4-dinitrophenol (DNP), accumulation of each drug increased, especially in resistant strains, indicating that the function of the active efflux (pump) system in these bacteria had been enhanced dramatically. Furthermore, both OmpF and OmpC in Ecs, OmpF-deficiency in R2 and R256 and OmpC-deficiency in R5 and R6 were observed.Conclusion The decreased accumulation of hydrophilic fluoroquinolones in E. coli involved OmpF-deficiency and active efflux (pump), and the latter may be an important factor.

  5. Adaptive mutations produce resistance to ciprofloxacin.

    OpenAIRE

    Riesenfeld, C; Everett, M.; Piddock, L J; Hall, B G

    1997-01-01

    Mutation to ciprofloxacin resistance continually occurred in nondividing Escherichia coli cells during a 7-day exposure to ciprofloxacin in agar, while no accumulation of rifampin resistance mutations was detected in those cells. We propose that the resistance mutations result from adaptive mutations, which preferentially produce phenotypes that promote growth in nondividing cells.

  6. Presence of qnr gene in Escherichia coli and Klebsiella pneumoniae resistant to ciprofloxacin isolated from pediatric patients in China

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    Wang Chuanqing

    2008-05-01

    Full Text Available Abstract Background Quinolone resistance in Enterobacteriaceae results mainly from mutations in type II DNA topoisomerase genes and/or changes in the expression of outer membrane and efflux pumps. Several recent studies have indicated that plasmid-mediated resistance mechanisms also play a significant role in fluoroquinolone resistance, and its prevalence is increasing worldwide. In China, the presence of the qnr gene in the clinical isolates of Enterobacteriaceae has been reported, but this transmissible quinolone resistance gene has not been detected in strains isolated singly from pediatric patients. Because quinolones associated with a variety of adverse side effects on children, they are not authorized for pediatric use. This study therefore aimed to investigate the presence of the qnr gene in clinical isolates of E. coli and K. pneumoniae from pediatric patients in China. Methods A total 213 of non-repetitive clinical isolates resistant to ciprofloxacin from E. coli and K. pneumoniae were collected from hospitalized patients at five children's hospital in Beijing, Shanghai, Guangzhou, and Chongqing. The isolates were screened for the plasmid-mediated quinolone resistance genes of qnrA, qnrB, and qnrS by PCR. Transferability was examined by conjugation with the sodium azide-resistant E. coli J53. All qnr-positive were analyzed for clonality by enterobacterial repetitive intergenic consensus (ERIC-PCR. Results The study found that 19 ciprofloxacin-resistant clinical isolates of E. coli and K. pneumoniae were positive for the qnr gene, and most of the qnr positive strains were ESBL producers. Conjugation experiments showed that quinolone resitance could be transferred to recipients. Apart from this, different DNA banding patterns were obtained by ERIC-PCR from positive strains, which means that most of them were not clonally related. Conclusion This report on transferable fluoroquinolone resistance due to the qnr gene among E. coli and K

  7. Cephalosporin and Ciprofloxacin Resistance in Salmonella, Taiwan

    OpenAIRE

    Yan, Jing-Jou; Chiou, Chien-Shun; Lauderdale, Tsai-Ling Yang; Tsai, Shu-Huei; Wu, Jiunn-Jong

    2005-01-01

    We report the prevalence and characteristics of Salmonella strains resistant to ciprofloxacin and extended-spectrum cephalosporins in Taiwan from January to May 2004. All isolates resistant to extended-spectrum cephalosporins carried bla CMY-2, and all ciprofloxacin-resistant Salmonella enterica serotype Choleraesuis isolates were genetically related.

  8. Increasing resistance of Staphylococcus aureus to ciprofloxacin.

    OpenAIRE

    Daum, T E; Schaberg, D R; Terpenning, M S; Sottile, W S; Kauffman, C A

    1990-01-01

    We demonstrated the marked emergence of resistance to ciprofloxacin among Staphylococcus arueus strains isolated at the Ann Arbor Veterans Administration Medical Center. All S. aureus isolates tested from 1984 to 1985 were susceptible, whereas 55.1% of methicillin-resistant and 2.5% of methicillin-susceptible strains from 1989 had high-level resistance to ciprofloxacin.

  9. Mechanisms of Reduced Susceptibility to Ciprofloxacin in Escherichia coli Isolates from Canadian Hospitals

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    Patricia J Baudry-Simner

    2012-01-01

    Full Text Available OBJECTIVE: To determine whether plasmid-mediated quinolone resistance (PMQR determinants play a role in the increasing resistance to fluoroquinolones among Escherichia coli isolates in Canadian hospitals, and to determine the mechanisms of reduced susceptibility to ciprofloxacin in a recent collection of 190 clinical E coli isolates.

  10. Increasing Ciprofloxacin Resistance Among Prevalent Urinary Tract Bacterial Isolates in Gaza Strip, Palestine

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    Zakaria El Astal

    2005-01-01

    Full Text Available This article presents the incidence of ciprofloxacin resistance among 480 clinical isolates obtained from patients with urinary tract infection (UTI during January to June 2004 in Gaza Strip, Palestine. The resistance rates observed were 15.0% to ciprofloxacin, 82.5% to amoxycillin, 64.4% to cotrimoxazole, 63.1% to doxycycline, 32.5% to cephalexin, 31.9% to nalidixic acid, and 10.0% to amikacin. High resistance to ciprofloxacin was detected among Acinetobacter haemolyticus (28.6%, Staphylococcus saprophyticus (25.0%,Pseudomonas aeruginosa (20.0%, Klebsiella pneumonia (17.6%, and Escherichia coli (12.0%. Minimal inhibitory concentration (MIC of ciprofloxacin evenly ranged from 4 to 32 μg/mL with a mean of 25.0 μg/mL. This study indicates emerging ciprofloxacin resistance among urinary tract infection isolates. Increasing resistance against ciprofloxacin demands coordinated monitoring of its activity and rational use of the antibiotics.

  11. Ciprofloxacin : Use and resistance in Community, Nursing Home and Hospital

    OpenAIRE

    van Hees, B.C.

    2011-01-01

    The aim of the studies described in this thesis was to analyze some aspects of ciprofloxacin use and clinical and (molecular) epidemiology of ciprofloxacin resistance in different settings, both within hospitals (chapter 3,4 and 6), community and nursing homes (chapter 2 and 5). With its broad spectrum against gram negative organisms and favorable pharmacokinetics, ciprofloxacin use has increased over the last two decades, as did resistance against ciprofloxacin. Chapter 2 describes a nation-...

  12. CIPROFLOXACIN RESISTANCE PATTERN AMONG BACTERIA ISOLATED FROM PATIENTS WITH COMMUNITY-ACQUIRED URINARY TRACT INFECTION

    Science.gov (United States)

    REIS, Ana Carolina Costa; SANTOS, Susana Regia da Silva; de SOUZA, Siane Campos; SALDANHA, Milena Góes; PITANGA, Thassila Nogueira; OLIVEIRA, Ricardo Riccio

    2016-01-01

    SUMMARY Objective: To identify the main bacterial species associated with community-acquired urinary tract infection (UTI) and to assess the pattern of ciprofloxacin susceptibility among bacteria isolated from urine cultures. Methods: We conducted a retrospective study in all the patients with community-acquired UTI seen in Santa Helena Laboratory, Camaçari, Bahia, Brazil during five years (2010-2014). All individuals who had a positive urine culture result were included in this study. Results: A total of 1,641 individuals met the inclusion criteria. Despite the fact that participants were female, we observed a higher rate of resistance to ciprofloxacin in males. The most frequent pathogens identified in urine samples were Escherichia coli, Klebsiella pneumoniae and Staphylococcus saprophyticus. Antimicrobial resistance has been observed mainly for ampicillin, sulfamethoxazole + trimethoprim and ciprofloxacin. Moreover, E. coli has shown the highest rate of ciprofloxacin resistance, reaching 36% of ciprofloxacin resistant strains in 2014. Conclusion: The rate of bacterial resistance to ciprofloxacin observed in the studied population is much higher than expected, prompting the need for rational use of this antibiotic, especially in infections caused by E. coli. Prevention of bacterial resistance can be performed through control measures to limit the spread of resistant microorganisms and a rational use of antimicrobial policy. PMID:27410913

  13. CIPROFLOXACIN RESISTANCE PATTERN AMONG BACTERIA ISOLATED FROM PATIENTS WITH COMMUNITY-ACQUIRED URINARY TRACT INFECTION

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    Ana Carolina Costa REIS

    2016-01-01

    Full Text Available SUMMARY Objective: To identify the main bacterial species associated with community-acquired urinary tract infection (UTI and to assess the pattern of ciprofloxacin susceptibility among bacteria isolated from urine cultures. Methods: We conducted a retrospective study in all the patients with community-acquired UTI seen in Santa Helena Laboratory, Camaçari, Bahia, Brazil during five years (2010-2014. All individuals who had a positive urine culture result were included in this study. Results: A total of 1,641 individuals met the inclusion criteria. Despite the fact that participants were female, we observed a higher rate of resistance to ciprofloxacin in males. The most frequent pathogens identified in urine samples were Escherichia coli, Klebsiella pneumoniae and Staphylococcus saprophyticus. Antimicrobial resistance has been observed mainly for ampicillin, sulfamethoxazole + trimethoprim and ciprofloxacin. Moreover, E. coli has shown the highest rate of ciprofloxacin resistance, reaching 36% of ciprofloxacin resistant strains in 2014. Conclusion: The rate of bacterial resistance to ciprofloxacin observed in the studied population is much higher than expected, prompting the need for rational use of this antibiotic, especially in infections caused by E. coli. Prevention of bacterial resistance can be performed through control measures to limit the spread of resistant microorganisms and a rational use of antimicrobial policy.

  14. Ciprofloxacin-Resistant Aeromonas hydrophila Cellulitis following Leech Therapy

    OpenAIRE

    Giltner, Carmen L.; Bobenchik, April M; Uslan, Daniel Z.; Deville, Jaime G.; Humphries, Romney M.

    2013-01-01

    We report a case of surgical site infection with ciprofloxacin-resistant Aeromonas hydrophila following leech therapy. Antimicrobial and genetic analyses of leech and patient isolates demonstrated that the resistant isolates originated from the leech gut microbiota. These data suggest that ciprofloxacin monotherapy as a prophylaxis regimen prior to leech therapy may not be effective in preventing infection.

  15. The first report of the qnrB19, qnrS1 and aac(6´-Ib-cr genes in urinary isolates of ciprofloxacin-resistant Escherichia coli in Brazil

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    Magna Cristina Paiva

    2012-08-01

    Full Text Available In this study, we investigated the presence of plasmid-mediated quinolone resistance (PMQR genes among 101 ciprofloxacin-resistant urinary Escherichia coli isolates and searched for mutations in the quinolone-resistance-determining regions (QRDRs of the DNA gyrase and topoisomerase IV genes in PMQR-carrying isolates. Eight isolates harboured the qnr and aac(6'-Ib-cr genes (3 qnrS1, 1 qnrB19 and 4 aac(6'-Ib-cr. A mutational analysis of the QRDRs in qnr and aac(6'-Ib-cr-positive isolates revealed mutations in gyrA, parC and parE that might be associated with high levels of resistance to quinolones. No mutation was detected in gyrB. Rare gyrA, parC and parE mutations were detected outside of the QRDRs. This is the first report of qnrB19, qnrS1 and aac(6'-Ib-cr -carrying E. coli isolates in Brazil.

  16. Ciprofloxacin : Use and resistance in Community, Nursing Home and Hospital

    NARCIS (Netherlands)

    van Hees, B.C.

    2011-01-01

    The aim of the studies described in this thesis was to analyze some aspects of ciprofloxacin use and clinical and (molecular) epidemiology of ciprofloxacin resistance in different settings, both within hospitals (chapter 3,4 and 6), community and nursing homes (chapter 2 and 5). With its broad spect

  17. Identification of the Efflux Transporter of the Fluoroquinolone Antibiotic Ciprofloxacin in Murine Macrophages: Studies with Ciprofloxacin-Resistant Cells▿

    OpenAIRE

    Marquez, Béatrice; Caceres, Nancy E; Mingeot-Leclercq, Marie-Paule; Tulkens, Paul M.; Van Bambeke, Françoise

    2009-01-01

    Ciprofloxacin, the most widely used totally synthetic antibiotic, is subject to active efflux mediated by a MRP-like transporter in wild-type murine J774 macrophages. To identify the transporter among the seven potential Mrps, we used cells made resistant to ciprofloxacin obtained by long-term exposure to increasing drug concentrations (these cells show less ciprofloxacin accumulation and provide a protected niche for ciprofloxacin-sensitive intracellular Listeria monocytogenes). In the prese...

  18. Selection of Cross-Resistance following Exposure of Pseudomonas aeruginosa Clinical Isolates to Ciprofloxacin or Cefepime

    OpenAIRE

    Alyaseen, Samer A.; Piper, Kerryl E.; Mark S. Rouse; James M Steckelberg; Patel, Robin

    2005-01-01

    Exposure of ciprofloxacin- and cefepime-susceptible Pseudomonas aeruginosa isolates to increasing concentrations of ciprofloxacin selected for ciprofloxacin resistance in 26/27 and cefepime nonsusceptibility in 7/27 isolates. Exposure of the isolates to increasing concentrations of cefepime selected for cefepime nonsusceptibility in 20/27 isolates but not for ciprofloxacin resistance.

  19. Ciprofloxacin residues in municipal biosolid compost do not selectively enrich populations of resistant bacteria.

    Science.gov (United States)

    Youngquist, Caitlin P; Liu, Jinxin; Orfe, Lisa H; Jones, Stephen S; Call, Douglas R

    2014-12-01

    Biosolids and livestock manure are valuable high-carbon soil amendments, but they commonly contain antibiotic residues that might persist after land application. While composting reduces the concentration of extractable antibiotics in these materials, if the starting concentration is sufficiently high then remaining residues could impact microbial communities in the compost and soil to which these materials are applied. To examine this issue, ciprofloxacin was added to biosolid compost feedstock to achieve a total concentration of 19 ppm, approximately 5-fold higher than that normally detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) (1 to 3.5 ppm). This feedstock was placed into mesh bags that were buried in aerated compost bays. Once a week, a set of bags was removed and analyzed (treated and untreated, three replicates of each; 4 weeks). Addition of ciprofloxacin had no effect on the recovery of resistant bacteria at any time point (P = 0.86), and a separate bioassay showed that aqueous extractions from materials with an estimated 59 ppm ciprofloxacin had no effect on the growth of a susceptible strain of Escherichia coli (P = 0.28). Regression analysis showed that growth of the susceptible strain of E. coli can be reduced given a sufficiently high concentration of ciprofloxacin (P < 0.007), a result that is consistent with adsorption being the primary mechanism of sequestration. While analytical methods detected biologically significant concentrations of ciprofloxacin in the materials tested here, the culture-based methods were consistent with the materials having sufficient adsorptive capacity to prevent typical concentrations of ciprofloxacin residues from selectively enriching populations of resistant bacteria.

  20. Patterns of Ciprofloxacin-Resistant Gram-Negative Bacteria Colonization in Nursing Home Residents

    OpenAIRE

    Dommeti, Parimala; WANG, Linda; Flannery, Erika L; Symons, Kathleen; Mody, Lona

    2011-01-01

    We evaluated the prevalence of colonization with all gram-negative bacilli (GNB) and with ciprofloxacin-resistant GNB among nursing home residents with and without indwelling devices. We found that device presence increases the risk of colonization with all GNB and with ciprofloxacin-resistant GNB. Colonization with ciprofloxacin-resistant GNB increases with decreasing functional status.

  1. Prevalence and role of efflux pump activity in ciprofloxacin resistance in clinical isolates of Klebsiella pneumoniae

    OpenAIRE

    Aathithan, S.; French, G L

    2011-01-01

    Abstract We investigated the prevalence and role of efflux pump activity and possible drug influx resistance in ciprofloxacin susceptibility amongst 26 distinct clinical isolates of Klebsiella pneumoniae of varying ciprofloxacin susceptibilities and known quinolone resistance-determining region (QRDR) genotypes. Cellular [14C]ciprofloxacin accumulation patterns and the amount of cell-associated [14C]ciprofloxacin of mid-logarithmic phase cells were determined before and after chall...

  2. Emergence of ciprofloxacin-resistant extended-spectrum β-lactamase-producing enteric bacteria in hospital wastewater and clinical sources.

    Science.gov (United States)

    Maheshwari, Meenu; Yaser, Nawar Hadi; Naz, Suraiya; Fatima, Mansha; Ahmad, Iqbal

    2016-06-01

    This study aimed to evaluate the incidence of ciprofloxacin-resistant extended-spectrum β-lactamase (ESBL)-producing enteric bacteria in hospital wastewater and clinical sources. Enteric bacteria, mainly Escherichia coli, were isolated from clinical sources (urinary tract and gastrointestinal tract infections; 80 isolates) and hospital wastewater (103 isolates). The antibiotic resistance profile and ESBL production of the isolates were investigated by disc diffusion assay and combined disc diffusion test, respectively. Plasmid profiling was performed by agarose gel electrophoresis, and elimination of resistance markers was performed by a plasmid curing experiment. Antibiotic susceptibility testing revealed a high incidence of β-lactam resistance, being highest to ampicillin (88.0%) followed by amoxicillin, ceftriaxone, cefpodoxime, cefotaxime, aztreonam, cefepime and ceftazidime. Among the non-β-lactam antibiotics, the highest resistance was recorded to nalidixic acid (85.7%). Moreover, 50.8% of enteric bacteria showed resistance to ciprofloxacin. Among 183 total enteric bacteria, 150 (82.0%) exhibited multidrug resistance. ESBL production was detected in 78 isolates (42.6%). A significantly higher incidence of ciprofloxacin resistance was observed among ESBL-producing enteric bacteria both in clinical (P=0.0015) and environmental isolates (P=0.012), clearly demonstrating a close association between ESBL production and ciprofloxacin resistance. Plasmid profiling of selected ESBL-positive strains indicated the presence of one or more plasmids of varying sizes. Plasmid curing resulted in loss of ciprofloxacin and cefotaxime resistance markers simultaneously from selected ESBL-positive isolates, indicating the close relationship of these markers. This study revealed a common occurrence of ciprofloxacin-resistant ESBL-producing enteric bacteria both in hospital wastewater and clinical sources, indicating a potential public health threat.

  3. Ciprofloxacin and probiotic Escherichia coli Nissle add-on treatment in active ulcerative colitis

    DEFF Research Database (Denmark)

    Petersen, Andreas Munk; Mirsepasi, Hengameh; Halkjær, Sofie Ingdam;

    2014-01-01

    BACKGROUND AND AIM: Ulcerative colitis (UC) is a chronic inflammatory bowel disease. The probiotic bacterium Escherichia coli Nissle 1917 (EcN) has been used to maintain and induce clinical remission in UC. Our aim was to test the effect of Ciprofloxacin and/or orally administered EcN as add-on to...

  4. Bactericidal activity of ciprofloxacin against amikacin- and cefotaxime-resistant gram-negative bacilli and methicillin-resistant staphylococci.

    OpenAIRE

    Simberkoff, M S; Rahal, J J

    1986-01-01

    The MICs and MBCs of ciprofloxacin were determined for clinical isolates of antibiotic-resistant aerobic bacteria. Decreased susceptibility to ciprofloxacin of cefotaxime- and amikacin-resistant Serratia marcescens and amikacin-resistant Pseudomonas aeruginosa strains were noted. The data suggest that ciprofloxacin susceptibility should be carefully monitored in treating patients with hospital-acquired bacterial infections.

  5. Ciprofloxacin-resistant methicillin-resistant Staphylococcus aureus in an acute-care hospital.

    OpenAIRE

    Raviglione, M. C.; Boyle, J. F.; Mariuz, P; Pablos-Mendez, A; Cortes, H; Merlo, A.

    1990-01-01

    Use of ciprofloxacin as an alternative to vancomycin for treatment of methicillin-resistant Staphylococcus aureus infection has been paralleled by the emergence of resistant strains. This phenomenon has also been noticed in our hospital. To confirm our observation, methicillin and ciprofloxacin susceptibilities were tested by disk diffusion and broth microdilution techniques. We studied 83 methicillin-resistant Staphylococcus aureus isolates obtained from various sources over a 4-month period...

  6. Ciprofloxacin conjugated zinc oxide nanoparticle: A camouflage towards multidrug resistant bacteria

    Indian Academy of Sciences (India)

    Prasun Patra; Shouvik Mitra; Nitai Debnath; Panchanan Pramanik; Arunava Goswami

    2014-04-01

    Gradual development of antibiotic resistant bacteria is producing severe global threat. Newer strategies are now being employed in order to control the microbial infections and to reduce the mortality as well as infection rates. Herein we describe successful synthesis of ZnO nanoparticles (ZNP) under microwave assisted condition followed by functionalization with ciprofloxacin, an antibiotic, using EDC/NHS chemistry. Successful conjugation of ciprofloxacin was confirmed by FTIR spectra. Ciprofloxacin-conjugated ZnO nanoparticles (ZN-CIP) exhibited excellent antibacterial activity against clinically isolated multidrug resistant bacterial strains of Escherichia coli, Staphylococcus aureus and Klebsiella sp. ZNP were small in size with particle size distribution 18–20 nm as obtained from transmission electron microscope (TEM). Surface topology was obtained from atomic force microscopic (AFM) image and x-ray diffraction confirmed that ZNP possessed hexagonal crystal structure. A concentration of 10 g/mL of ZN-CIP was a benchmark concentration. During evaluation of minimum inhibitory concentration (MIC) values, similar concentration of antibiotic was incapable of producing antibacterial activity.

  7. Correlation between Fecal Concentrations of Ciprofloxacin and Fecal Counts of Resistant Enterobacteriaceae in Piglets Treated with Ciprofloxacin: toward New Means To Control the Spread of Resistance? : CIPROFLOXACIN LEVELS AND RESISTANT BACTERIA IN FECES

    OpenAIRE

    Nguyen, Thu Thuy; Chachaty, Elisabeth; Huy, Clarisse; Cambier, Carole; de Gunzburg, Jean; Mentré, France; Andremont, Antoine

    2012-01-01

    We assessed in a piglet model the relationship between fecal ciprofloxacin concentrations and ciprofloxacin-resistant Enterobacteriaceae counts. Twenty-nine piglets were orally treated with placebo or with 1.5 or 15 mg ciprofloxacin/kg of body weight/day from day 1 (D1) to D5. Areas under the curve (AUC) of concentrations increased sharply with dose and correlated positively with AUC of resistant bacteria log counts between D1 and D9. Removing residual colonic quinolones could help to control...

  8. Impact of low-level fluoroquinolone resistance genes qnrA1, qnrB19 and qnrS1 on ciprofloxacin treatment of isogenic Escherichia coli strains in a murine urinary tract infection model

    DEFF Research Database (Denmark)

    Jakobsen, Lotte; Cattoir, Vincent; Jensen, Klaus S;

    2012-01-01

    To study the impact of qnrA1, qnrB19 and qnrS1 on the ciprofloxacin treatment of urinary tract infection (UTI).......To study the impact of qnrA1, qnrB19 and qnrS1 on the ciprofloxacin treatment of urinary tract infection (UTI)....

  9. Sublethal Ciprofloxacin Treatment Leads to Rapid Development of High-Level Ciprofloxacin Resistance during Long-Term Experimental Evolution of Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jørgensen, Karin Meinike; Wassermann, Tina; Jensen, Peter Østrup;

    2013-01-01

    that mutants with high-level ciprofloxacin resistance are selected in P. aeruginosa bacterial populations exposed to sub-MICs of ciprofloxacin. This can have implications for the long-term persistence of resistant bacteria and spread of antibiotic resistance by exposure of commensal bacterial flora to low......The dynamics of occurrence and the genetic basis of ciprofloxacin resistance were studied in a long-term evolution experiment (940 generations) in wild-type, reference strain (PAO1) and hypermutable (PAOΔmutS and PAOMY-Mgm) P. aeruginosa populations continuously exposed to sub-MICs (1....../4) of ciprofloxacin. A rapid occurrence of ciprofloxacin-resistant mutants (MIC of ≥12 μg/ml, representing 100 times the MIC of the original population) were observed in all ciprofloxacin-exposed lineages of PAOΔmutS and PAOMY-Mgm populations after 100 and 170 generations, respectively, and in one of the PAO1...

  10. Sublethal Ciprofloxacin Treatment Leads to Rapid Development of High-Level Ciprofloxacin Resistance during Long-Term Experimental Evolution of Pseudomonas aeruginosa

    OpenAIRE

    Jørgensen, Karin Meinike; Wassermann, Tina; Jensen, Peter Østrup; Hengzuang, Wang; Molin, Søren; Høiby, Niels; Ciofu, Oana

    2013-01-01

    The dynamics of occurrence and the genetic basis of ciprofloxacin resistance were studied in a long-term evolution experiment (940 generations) in wild-type, reference strain (PAO1) and hypermutable (PAOΔmutS and PAOMY-Mgm) P. aeruginosa populations continuously exposed to sub-MICs (1/4) of ciprofloxacin. A rapid occurrence of ciprofloxacin-resistant mutants (MIC of ≥12 μg/ml, representing 100 times the MIC of the original population) were observed in all ciprofloxacin-exposed lineages of PAO...

  11. Bacterial resistance to ciprofloxacin in Greece: results from the National Electronic Surveillance System. Greek Network for the Surveillance of Antimicrobial Resistance.

    OpenAIRE

    Vatopoulos, A. C.; Kalapothaki, V.; Legakis, N. J.

    1999-01-01

    According to 1997 susceptibility data from the National Electronic System for the Surveillance of Antimicrobial Resistance, Greece has high rates of ciprofloxacin resistance. For most species, the frequency of ciprofloxacin-resistant isolates (from highest to lowest, by patient setting) was as follows: intensive care unit > surgical > medical > outpatient. Most ciprofloxacin-resistant strains were multidrug resistant.

  12. Alteration of GyrA Amino Acid Required for Ciprofloxacin Resistance in Klebsiella pneumoniae Isolates in China▿

    OpenAIRE

    Fu, Yingmei; Guo, Lishuang; Xu, Yan; Zhang, Wenli; Gu, Jiaao; Xu, Jianfeng; Chen, Xiaobei; Zhao, Yuehui; Ma, Jiayu; Liu, Xinghan; Zhang, Fengmin

    2008-01-01

    Resistance to ciprofloxacin was detected in 111 (48.1%) isolates of Klebsiella pneumoniae from China. GyrA alterations were identified in the ciprofloxacin-resistant and ciprofloxacin-susceptible isolates. The results, including previously published data, indicate that the single substitution Ser83→Ile and three types of double mutations at Ser83 and Asp87 were required for ciprofloxacin resistance (P < 0.05).

  13. Rapid identification of bacterial resistance to Ciprofloxacin using surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Kastanos, Evdokia; Hadjigeorgiou, Katerina; Pitris, Costas

    2014-02-01

    Due to its effectiveness and broad coverage, Ciprofloxacin is the fifth most prescribed antibiotic in the US. As current methods of infection diagnosis and antibiotic sensitivity testing (i.e. an antibiogram) are very time consuming, physicians prescribe ciprofloxacin before obtaining antibiogram results. In order to avoid increasing resistance to the antibiotic, a method was developed to provide both a rapid diagnosis and the sensitivity to the antibiotic. Using Surface Enhanced Raman Spectroscopy, an antibiogram was obtained after exposing the bacteria to Ciprofloxacin for just two hours. Spectral analysis revealed clear separation between sensitive and resistant bacteria and could also offer some inside into the mechanisms of resistance.

  14. Mutation patterns in gyrA and parC genes of ciprofloxacin resistant isolates of Neisseria gonorrhoeae from India

    OpenAIRE

    Chaudhry, U; Ray, K; Bala, M; Saluja, D

    2002-01-01

    Aim: To analyse mutations in the gyrA and parC genes leading to possible increase in ciprofloxacin resistance (high MIC values for ciprofloxacin) in clinical isolates of Neisseria gonorrhoeae in Delhi, India.

  15. Escherichia coli antibiotic resistance in emergency departments. Do local resistance rates matter?

    Science.gov (United States)

    Grignon, O; Montassier, E; Corvec, S; Lepelletier, D; Hardouin, J-B; Caillon, J; Batard, E

    2015-03-01

    Ciprofloxacin and cotrimoxazole are recommended to treat uncomplicated pyelonephritis and uncomplicated cystitis, respectively, provided that local resistance rates of uropathogens do not exceed specified thresholds (10 and 20 %, respectively). However, Escherichia coli resistance rates in Emergency Departments (ED) remain poorly described. Our objectives were to assess E. coli ciprofloxacin and cotrimoxazole resistance rates in EDs of a French administrative region, and to determine if resistance rates differ between EDs. This was a retrospective study of E. coli urine isolates sampled in ten EDs between 2007 and 2012. The following risk factors for resistance were tested using logistic regression: ED, sex, age, sampling year, sampling month. A total of 17,527 isolates were included. Ciprofloxacin local resistance rates (range, 5.3 % [95 % CI, 4.0-7.1 %] to 11.7 % [95 % CI, 5.2-23.2 %]) were ≤10 % in nine EDs in 2012. Five EDs were risk factors for ciprofloxacin resistance, as were male sex, age and sampling in April or October. Cotrimoxazole local resistance rates (range, 13.3 % [95 % CI, 6.3-25.1 %] to 20.4 % [95 % CI, 18.9-22.0 %]) were ≤20 % in seven EDs in 2012. Five EDs were risk factors for cotrimoxazole resistance, as were age, sampling between October and December, and sampling in 2011 and 2012. We found a significant variability of E. coli ciprofloxacin and cotrimoxazole resistance rates among EDs of a small region. These differences impact on the feasibility of empirical treatment of urinary tract infections with ciprofloxacin or cotrimoxazole in a given ED. Continuous local survey of antibacterial resistance in ED urinary isolates is warranted to guide antibacterial therapy of urinary tract infections. PMID:25339200

  16. Cellular Accumulation and Activity of Quinolones in Ciprofloxacin-Resistant J774 Macrophages

    OpenAIRE

    Michot, Jean-Michel; Heremans, Marie F.; Caceres, Nancy E; Mingeot-Leclercq, Marie-Paule; Tulkens, Paul M.; Van Bambeke, Françoise

    2006-01-01

    Ciprofloxacin is the substrate for a multidrug resistance-related protein (MRP)-like multidrug transporter in J774 mouse macrophages, which also modestly affects levofloxacin but only marginally affects garenoxacin and moxifloxacin (J.-M. Michot et al., Antimicrob. Agents Chemother. 49:2429-2437, 2005). Two clones of ciprofloxacin-resistant cells were obtained by a stepwise increase in drug concentration (from 34 to 51 to 68 mg/liter) in the culture fluid. Compared to wild-type cells, ciprofl...

  17. Ciprofloxacin causes persister formation by inducing the TisB toxin in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Tobias Dörr

    2010-02-01

    Full Text Available Bacteria induce stress responses that protect the cell from lethal factors such as DNA-damaging agents. Bacterial populations also form persisters, dormant cells that are highly tolerant to antibiotics and play an important role in recalcitrance of biofilm infections. Stress response and dormancy appear to represent alternative strategies of cell survival. The mechanism of persister formation is unknown, but isolated persisters show increased levels of toxin/antitoxin (TA transcripts. We have found previously that one or more components of the SOS response induce persister formation after exposure to a DNA-damaging antibiotic. The SOS response induces several TA genes in Escherichia coli. Here, we show that a knockout of a particular SOS-TA locus, tisAB/istR, had a sharply decreased level of persisters tolerant to ciprofloxacin, an antibiotic that causes DNA damage. Step-wise administration of ciprofloxacin induced persister formation in a tisAB-dependent manner, and cells producing TisB toxin were tolerant to multiple antibiotics. TisB is a membrane peptide that was shown to decrease proton motive force and ATP levels, consistent with its role in forming dormant cells. These results suggest that a DNA damage-induced toxin controls production of multidrug tolerant cells and thus provide a model of persister formation.

  18. Fleroxacin resistance in Escherichia coli.

    OpenAIRE

    Chapman, J S; Bertasso, A; Georgopapadakou, N H

    1989-01-01

    Spontaneous fleroxacin-resistant mutants of Escherichia coli K-12 were isolated at a frequency of 10(-10) to 10(-11) mutants per CFU plated. All mutants exhibited quinolone-resistant replicative DNA biosynthesis, and 4 of 11 mutants also had decreased amounts of OmpF or OmpC porin. None of the mutants had changes solely in porin proteins.

  19. Ertapenem Resistance of Escherichia coli

    OpenAIRE

    Lartigue, Marie-Frédérique; Poirel, Laurent; Poyart, Claire; Réglier-Poupet, Hélène; Nordmann, Patrice

    2007-01-01

    An ertapenem-resistant Escherichia coli isolate was recovered from peritoneal fluid in a patient who had been treated with imipenem/cilastatin for 10 days. Ertapenem resistance may be explained by a defect in the outer membrane protein and production of extended-spectrum β-lactamase CTX-M-2.

  20. International Spread of an Epidemic Population of Salmonella enterica Serotype Kentucky ST198 Resistant to Ciprofloxacin

    DEFF Research Database (Denmark)

    Le Hello, Simon; Hendriksen, Rene S.; Doublet, Benoit;

    2011-01-01

    National Salmonella surveillance systems from France, England and Wales, Denmark, and the United States identified the recent emergence of multidrug-resistant isolates of Salmonella enterica serotype Kentucky displaying high-level resistance to ciprofloxacin. A total of 489 human cases were ident...

  1. In vitro activity of ciprofloxacin against aerobic gram-negative bacteria.

    OpenAIRE

    Rudin, J E; Norden, C W; Shinners, E M

    1984-01-01

    For 177 gram-negative isolates, the MICs for ciprofloxacin ranged from 0.02 microgram/ml (Escherichia coli) to 0.31 microgram/ml (Pseudomonas aeruginosa). In time-kill curves, ciprofloxacin at 8 X the MIC almost completely killed 10(6) CFU of P. aeruginosa by 24 h. Ciprofloxacin at 4 X the MIC allowed bacterial regrowth by 24 h, with development of partial resistance to ciprofloxacin.

  2. The antibiotic ciprofloxacin produces superoxide in Escherichia coli even in the absence of radiation

    International Nuclear Information System (INIS)

    Full text: Studies of most fluoroquinolones have reported that they cause phototoxicity, that involves reactions forming both singlet oxygen and superoxide anion (O2$-), upon exposure to sunligth or UV irradiation. In this study we examined the formation light-independent of O2$- in Escherichia coli mediated by the fluoro quinolone ciprofloxacin. We employed a semiquantitative method as indicator of intracelullar levels of O2$- in vivo, on the basis of the inactivation of aconitase by O2$- . Several enzymes, including aconitase and 6P-gluconate dehydratase, contain [4Fe-4S] centers prone to O2$- oxidation. The results indicated that a fraction (∼30%), was inactivated with a very low dose of antibiotic in the absence of illumination. In this condition, the level of O2$- increased almost four times and up to ten fold, under UV irradiation. We could also demonstrate activation of the response to O2$- mediated by the soxRS regulon and dose-dependent increases in superoxide dismutase activity. We detected O2$- production with the tetrazolium dye XTT, upon UV irradiation, but failed to detect it in the absence of light, probably because this method is less sensitive than enzyme inactivation. Oxidative stress is a side-effect of these drugs and can induce cytotoxic reactions in cells. (author)

  3. Ciprofloxacin Resistance and Gonorrhea Incidence Rates in 17 Cities, United States, 1991–2006

    Science.gov (United States)

    Kirkcaldy, Robert D.; Gift, Thomas L.; Owusu-Edusei, Kwame; Weinstock, Hillard S.

    2014-01-01

    Antimicrobial drug resistance can hinder gonorrhea prevention and control efforts. In this study, we analyzed historical ciprofloxacin resistance data and gonorrhea incidence data to examine the possible effect of antimicrobial drug resistance on gonorrhea incidence at the population level. We analyzed data from the Gonococcal Isolate Surveillance Project and city-level gonorrhea incidence rates from surveillance data for 17 cities during 1991–2006. We found a strong positive association between ciprofloxacin resistance and gonorrhea incidence rates at the city level during this period. Their association was consistent with predictions of mathematical models in which resistance to treatment can increase gonorrhea incidence rates through factors such as increased duration of infection. These findings highlight the possibility of future increases in gonorrhea incidence caused by emerging cephalosporin resistance. PMID:24655615

  4. Fluoroquinolone resistance mechanisms in urinary tract pathogenic Escherichia coli isolated during rapidly increasing fluoroquinolone consumption in a low-use country

    DEFF Research Database (Denmark)

    Christiansen, Nina; Nielsen, Lene; Jakobsen, Lotte;

    2011-01-01

    Resistance to ciprofloxacin in Escherichia coli from urinary tract infections (UTI) in Denmark is increasing parallel to increased use of fluoroquinolones both in Denmark and in other European countries. The objective was to investigate the occurrence of ciprofloxacin resistance mechanisms......, phenotypic coresistance, and if ciprofloxacin resistance was caused by clonal spread or to individual mutational events in a collection of consecutively obtained E. coli submitted to a clinical microbiology department at a Danish hospital. One hundred four UTI-related E. coli resistant toward nalidixic acid...... to >= 3 antimicrobial classes, 83%). Ciprofloxacin-resistant isolates showed at least one target mutation. A significant, positive correlation was found regarding MIC of ciprofloxacin and the number of target mutations. Efflux was found as a resistance mechanism in 77% of isolates tested (n = 60). The aac...

  5. Contribution of AcrAB efflux pump to ciprofloxacin resistance in Klebsiella pneumoniae isolated from burn patients

    Directory of Open Access Journals (Sweden)

    Pakzad, Iraj

    2013-11-01

    Full Text Available [english] Resistance to fluoroquinolones has been recently increased among bacterial strains isolated from outpatients. Multidrug-resistant is one of the major organisms isolated from burn patients and the AcrAB efflux pump is the principal pump contributing to the intrinsic resistance in against multiple antimicrobial agents including ciprofloxacin and other fluoroquinolones. Fifty-two isolated from burn patients in Shahid Motahari hospital and confirmed by conventional biochemical tests. Antimicrobial susceptibility testing was done according to CLSI 2011 guidelines, to determine the antimicrobial resistance pattern of isolates. A gene was detected among ciprofloxacin-resistant isolates by PCR assay. MICs to ciprofloxacin were measured with and without carbonyl cyanide . Forty out of the 52 isolated from burn patients in Shahid Motahari hospital were resistant to ciprofloxacin according to breakpoint of CLSI guideline. PCR assay for A gene demonstrated that all ciprofloxacin-resistant isolates harbored A gene coding the membrane fusion protein AcrA and is a part of AcrAB efflux system. Among these isolates, 19 strains (47.5% showed 2 to 32 fold reduction in MICs after using CCCP as an efflux pump inhibitor. The other 21 strains (52.5% showed no disparity in MICs before and after using CCCP. In conclusion, the AcrAB efflux system is one of the principal mechanisms contribute in ciprofloxacin resistance among isolates but there are some other mechanisms interfere with ciprofloxacin resistance such as mutation in target proteins of DNA gyrase of topoisomerase IV enzymes.

  6. Ciprofloxacin residue and antibiotic-resistant biofilm bacteria in hospital effluent.

    Science.gov (United States)

    Ory, Jérôme; Bricheux, Geneviève; Togola, Anne; Bonnet, Jean Louis; Donnadieu-Bernard, Florence; Nakusi, Laurence; Forestier, Christiane; Traore, Ousmane

    2016-07-01

    Discharge of antimicrobial residues and resistant bacteria in hospital effluents is supposed to have strong impacts on the spread of antibiotic resistant bacteria in the environment. This study aimed to characterize the effluents of the Gabriel Montpied teaching hospital, Clermont-Ferrand, France, by simultaneously measuring the concentration of ciprofloxacin and of biological indicators resistant to this molecule in biofilms formed in the hospital effluent and by comparing these data to ciprofloxacin consumption and resistant bacterial isolates of the hospital. Determination of the measured environmental concentration of ciprofloxacin by spot sampling and polar organic chemical integrative (POCIS) sampling over 2 weeks, and comparison with predicted environmental concentrations produced a hazard quotient >1, indicating a potential ecotoxicological risk. A negative impact was also observed with whole hospital effluent samples using the Tetrahymena pyriformis biological model. During the same period, biofilms were formed within the hospital effluent, and analysis of ciprofloxacin-resistant isolates indicated that Gamma-Proteobacteria were numerous, predominantly Aeromonadaceae (69.56%) and Enterobacteriaceae (22.61%). Among the 115 isolates collected, plasmid-mediated fluoroquinolone-resistant genes were detected, with mostly aac(6')-lb-cr and qnrS. In addition, 60% of the isolates were resistant to up to six antibiotics, including molecules mostly used in the hospital (aminosides and third-generation cephalosporins). In parallel, 1247 bacteria isolated from hospitalized patients and resistant to at least one of the fluoroquinolones were collected. Only 5 of the 14 species identified in the effluent biofilm were also found in the clinical isolates, but PFGE typing of the Gram-negative isolates found in both compartments showed there was no clonality among the strains. Altogether, these data confirm the role of hospital loads as sources of pollution for wastewater

  7. Preparation of ciprofloxacin-coated zinc oxide nanoparticles and their antibacterial effects against clinical isolates of Staphylococcus aureus and Escherichia coli

    DEFF Research Database (Denmark)

    Seif, Sepideh; Kazempour, Zarah Bahri; Pourmand, Mohammad Reza;

    2011-01-01

    carbonyl group in ciprofloxacin is actively involved in forming chemical - rather than physical - bonds with zinc oxide nanoparticles. Also the antibacterial activity of free zinc oxide nanoparticles and ciprofloxacin-coated zinc oxide nanoparticles have been evaluated against different clinical isolates...... pure ciprofloxacin) considerably enhanced the antibacterial activity of zinc oxide nanoparticles against different isolates of Staphylococcus aureus and Escherichia coli (4 to 32 fold increase). The result is of particular value, since it demonstrates that, by using biocompatible zinc oxide...... nanoparticles in combination therapy, lower amounts of antibiotics may be needed...

  8. In vitro ciprofloxacin resistance patterns of gram positive bacteria isolated from clinical specimens in a teaching hospital in Saudi Arabia

    International Nuclear Information System (INIS)

    Over the last few decades the ever-increasing level of bacterial resistance to antimicrobials has been a cause of worldwide concern. Fluoroquinolones, particularly ciprofloxacin has been used indiscriminately for both gram-positive and gram-negative bacterial infections. The increased use of ciprofloxacin has led to a progressive loss of bacterial susceptibility to this antibiotic. Therefore it is necessary to have update knowledge of resistance pattern of bacteria to this antibiotic so that alternate appropriate antibiotics can be used for ciprofloxacin-resistant bacterial infections. Objective: To evaluate the trends of ciprofloxacin resistance pattern in commonly isolated gram positive bacteria over time in a Saudi Arabian teaching hospital. Methods: A retrospective analysis was carried out for ciprofloxacin susceptibility patterns of 5534 isolates of gram-positive bacteria isolated from clinical specimens submitted to microbiology laboratories at King Fahd Hospital of the University (KFHU), Al-Khobar, Saudi Arabia during the period from January 2002 to August 2005. Results: Increase in ciprofloxacin resistance rates with some fluctuations, among these isolates, were observed. For Staphylococcus aureus, it varied from 4.62, 1.83, 7.01 and 3.98%, methicillin resistant Staphylococcus aureus (MRSA) 97.92, 97.75, 87.01 and 88.26%, Streptococcus pyogenes 5.35, 4.47, 14.44 and 3.53% during the years 2002, 2003, 2004 and 2005 respectively. Cirprofloxacin resistance during the years 2002, 2004 and 2005 for other isolates was as follows: Streptococcus pneumoniae, 30.23, 23.02 and 26.47%; enterococcus group D, 43.05, 20.68 and 57.03% and non-enterococcus group D, 62.96, 76.92 and 87.50% respectively. Conclusion: Ciprofloxacin resistance in gram positive bacterial clinical isolates particularly Staphylococcus aureus, methicillin resistant Staphylococcus aureus (MRSA) enterococcus group D, and non-enterococcus group D, has greatly increased and ciprofloxacin no more remains

  9. Influence of induced ciprofloxacin resistance on efflux pump activity of Klebsiella pneumoniae

    Institute of Scientific and Technical Information of China (English)

    Hai-qin ZHONG; Shun ZHANG; Hong PAN; Ting CAI

    2013-01-01

    The efflux pump (EP) is one of the major mechanisms of antibiotic resistance in Klebsiella pneumoniae.However,there are few reports on the effect of the abuse of antibiotic use on the activity of EPs.To determine whether the use of low efficacy antibiotics has any effect on the activity of EPs and induces drug resistance in K.pneumoniae,we investigated the effect of ciprofloxacin on the activity of EPs in K.pneumoniae strains.Methods:Sixteen susceptible K.pneumoniae strains were isolated from patients and their minimum inhibitory concentrations (MICs) of ciprofloxacin were measured in the absence and presence of the pump inhibitor carbonyl cyanide m-chlorophenyl hydrazone (CCCP).The strains were then induced with a gradient of ciprofloxacin until the MICs of the strains showed no further increase,to obtain induced resistant strains.The EP activities of the strains before and after induction were compared using EP inhibition and ethidium bromide (EtBr) accumulation assays.Results:The MIC values of the strains were 16-256 times higher after induction than before induction.In the presence of CCCP,the MIC values of 50% of the induced strains were 2-4-fold lower than that in the absence of this inhibitor.The EtBr accumulation assay showed that the fluorescence of EtBr in the induced cells was lower than that in the cells before induction.Conclusions:EPs are widespread in susceptible and drug-resistant K.pneumoniae strains.Induction with ciprofloxacin may increase the activity of EPs in K.pneumoniae.The EtBr accumulation assay is more sensitive than the EP inhibition assay in evaluating the activity of EPs in K.pneumoniae.

  10. Quinolone resistance and ESBL/AmpC’s in commensal Escherichia coli in veal calves : prevalence and molecular characterization

    NARCIS (Netherlands)

    Hordijk, J.

    2013-01-01

    In this thesis the prevalence and molecular characteristics of resistance to (fluoro)quinolones and Extended Spectrum Cephalosporins (ESC) in veal calves were described using Escherichia coli as an indicator organism. Ciprofloxacin and nalidixic acid were used as indicator antimicrobials for quinolo

  11. The effect of sub-minimum inhibitory concentration of ciprofloxacin concentrations on enteroaggregative Escherichia coli and the role of the surface protein dispersin

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Ninell P [ORNL; Fowlkes, Jason Davidson [ORNL; Trevino-Dopatka, Sonia [ORNL; Maggart, Michael J [ORNL; Boisen, Nadia [University of Virginia School of Medicine; Doktycz, Mitchel John [ORNL; Nataro, James [University of Virginia School of Medicine; Allison, David P [ORNL

    2011-01-01

    Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

  12. Effects of sub-minimum inhibitory concentrations of ciprofloxacin on enteroaggregative Escherichia coli and the role of the surface protein dispersin

    Energy Technology Data Exchange (ETDEWEB)

    Fowlkes, Jason Davidson [ORNL; Doktycz, Mitchel John [ORNL; Allison, David Post [ORNL

    2011-01-01

    Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhoea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

  13. Streptococcus pneumoniae Isolates with Reduced Susceptibility to Ciprofloxacin in Spain: Clonal Diversity and Appearance of Ciprofloxacin-Resistant Epidemic Clones

    OpenAIRE

    Alou, Luis; Ramirez, Mario; García-Rey, César; Prieto, José; de Lencastre, Hermínia

    2001-01-01

    Analysis of the pulsed-field gel electrophoretic profiles of 82 pneumococcal isolates with reduced susceptibility to ciprofloxacin (RSC) and of 90 co-occurring susceptible isolates indicates a considerable genetic diversity among isolates with RCS and points to a close relation between the two groups. This finding suggests that pneumococci with RCS emerge through independent mutational events.

  14. Molecular analysis of ciprofloxacin resistance among non-typhoidal Salmonella with reduced susceptibility to ciprofloxacin isolated from patients at a tertiary care hospital in Kuala Lumpur, Malaysia.

    Science.gov (United States)

    Karunakaran, Rina; Tay, Sun Tee; Rahim, Fairuz Fadzilah; Lim, Bee Bee; Puthucheary, Savithri D

    2014-01-01

    We investigated the prevalence of non-typhoidal Salmonella (NTS) with "reduced susceptibility to ciprofloxacin" (RS-Cip) (minimum inhibitory concentration [MIC], 0.12-1.0 μg/mL) as well as their resistance genes in 75 NTS isolates (53 from stool, 21 from blood, and 1 from urine) from patients at a tertiary care Malaysian hospital between January and December 2009. RS-Cip was detected in 24/75 (32.0%) isolates. Using the ciprofloxacin MIC interpretive criteria for Salmonella in the Clinical and Laboratory Standards Institute 2013 guidelines, 51/75 (68.0%) isolates were found to be sensitive, 22/75 (29.3%) were intermediate, and 2/75 (2.7%) were resistant to ciprofloxacin. The 24 isolates that were intermediate or resistant to ciprofloxacin were the same isolates categorized as having RS-Cip. Among the 23 tested isolates with RS-Cip, the qnrS gene was detected in 17/23 (73.9%) and single gyrA mutations were detected in 6/23 (26.1%) (Asp87Tyr [n = 3], Asp87Asn [n = 2], and Ser83Phe [n = 1]). A parC (Thr57Ser) mutation was detected in 13/23 (56.5%) isolates, coexisting with either a qnrS gene or a gyrA mutation. The high incidence of the qnrS gene among isolates with RS-Cip needs to be monitored because qnr genes can spread via plasmids and aid in the emergence of increased resistance levels.

  15. Genetic Diversity among Ciprofloxacin Resistant Enterococcus faecalis Isolated from Clinical Specimens with Pulsed-Field Gel Electrophoresis (PFGE Method

    Directory of Open Access Journals (Sweden)

    Moinian M

    2013-03-01

    Full Text Available Abstract Background and objective: Resistance to ciprofloxacin among Enterococcus faecalis (E.f isolates especially in UTI makes difficulties for treatment. In this study, the genetic diversity using PFGE method and detection of resistance genes including parC, gyrA , gyrB and parE among ciprofloxacin resistant E.f isolated from clinical specimens, are determined. Materials and methods: A total of 384 entreococcal isolates were collected from 6 hospitals and 3 private laboratories in Tehran and 50 ciprofloxacin resistant E.f isolates were obtained. Identification of species and resistance genes were done by PCR method. Antimicrobial and minimum inhibitory concentration (MICs tests were assayed with standard methods and finally genotyping was accomplished using PFGE method. Results: The range of ciprofloxacin MICs was 16 to 512 µg/ml. All of these isolates contained parC, 98 % gyrA , gyrB and 80 % parE genes. PFGE analysis, grouped 50 strains in 11 common types and 7 single types. The P4, P9 and P10 genotypes were shared between hospital and community isolates. Conclusion: According to these results the E.f isolates showed high clonal diversity. Because of the ciprofloxacin high MICs level among common pulsotypes we concluded that they have various distributions which may be due to highly transmission of resistant genes among enterococci. Indeed the colonized patients with these resistant isolates are reservoir for releasing of the resistant genes to community which requires more surveillance programs.

  16. Effect of land application of manure from enrofloxacin-treated chickens on ciprofloxacin resistance of Enterobacteriaceae in soil.

    Science.gov (United States)

    Pourcher, A-M; Jadas-Hécart, A; Cotinet, P; Dabert, P; Ziebal, C; Le Roux, S; Moraru, R; Heddadj, D; Kempf, I

    2014-06-01

    A field plot experiment was carried out to evaluate the impact of spreading chicken manure containing enrofloxacin (ENR) and its metabolite ciprofloxacin (CIP), on the levels of CIP-resistant Enterobacteriaceae in soil. The manures from chickens treated with ENR and from untreated control chickens were applied on six plots. Total and CIP-resistant Enterobacteriaceae were counted on Violet Red Bile Glucose medium containing 0 to 16mg L(-1) of CIP. A total of 145 isolates were genotyped by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The minimum inhibitory concentration (MIC) of CIP for the isolates of each ERIC-PCR profile was determined. The most frequently isolated Enterobacteriaceae included Escherichia coli, and to a lesser extent, Enterobacter and 5 other genera from environmental origin. The composition of the E. coli community differed between manure and manured soil suggesting that the E. coli genotypes determined by ERIC-PCR varied significantly in their ability to survive in soil. One of these genotypes, including both susceptible and resistant isolates, was detected up to 89 days after the manure was applied. Most of the E. coli isolated in soil amended with manure from treated chickens was resistant to CIP (with a MIC ranging between 2 and 32mg L(-1)). In contrast, despite the presence of ENR in soil at concentrations ranging from 13-518μg kg(-1), the environmental Enterobacteriaceae isolates had a CIP MIC≤0.064mg L(-1), except one isolate which had a MIC of 0.25mg L(-1), These results showed that spreading manure from ENR-treated chickens enabled CIP-resistant E. coli to persist for at least three months in the soil. However, neither the presence of fluoroquinolones, nor the persistence of CIP-resistant E. coli, increased the CIP-susceptibility of environmental Enterobacteriaceae.

  17. Emergence of Ciprofloxacin-Resistant Salmonella enterica Serovar Typhi in Italy.

    Directory of Open Access Journals (Sweden)

    Aurora García-Fernández

    Full Text Available In developed countries, typhoid fever is often associated with persons who travel to endemic areas or immigrate from them. Typhoid fever is a systemic infection caused by Salmonella enterica serovar Typhi. Because of the emergence of antimicrobial resistance to standard first-line drugs, fluoroquinolones are the drugs of choice. Resistance to ciprofloxacin by this Salmonella serovar represents an emerging public health issue. Two S. enterica ser. Typhi strains resistant to ciprofloxacin (CIP were reported to the Italian surveillance system for foodborne and waterborne diseases (EnterNet-Italia in 2013. The strains were isolated from two Italian tourists upon their arrival from India. A retrospective analysis of 17 other S. enterica ser. Typhi strains isolated in Italy during 2011-2013 was performed to determine their resistance to CIP. For this purpose, we assayed for susceptibility to antimicrobial agents and conducted PCR and nucleotide sequence analyses. Moreover, all strains were typed using pulsed-field gel electrophoresis to evaluate possible clonal relationships. Sixty-eight percent of the S. enterica ser. Typhi strains were resistant to CIP (MICs, 0.125-16 mg/L, and all isolates were negative for determinants of plasmid-mediated quinolone resistance. Analysis of sequences encoding DNA gyrase and topoisomerase IV subunits revealed mutations in gyrA, gyrB, and parC. Thirteen different clonal groups were detected, and the two CIP-resistant strains isolated from the individuals who visited India exhibited the same PFGE pattern. Because of these findings, the emergence of CIP-resistant S. enterica ser. Typhi isolates in Italy deserves attention, and monitoring antibiotic susceptibility is important for efficiently managing cases of typhoid fever.

  18. Intraventricular ciprofloxacin usage in treatment of multidrug-resistant central nervous system infections: report of four cases

    Directory of Open Access Journals (Sweden)

    Ayse Karaaslan

    2014-12-01

    Full Text Available In recent years, multidrug-resistant microorganisms appear as important nosocomial pathogens which treatment is quite difficult. As sufficient drug levels could not be achieved in cerebrospinal fluid during intravenous antibiotic therapy for central nervous system infections and due to multidrug-resistance treatment alternatives are limited. In this study, four cases of central nervous system infections due to multidrug-resistant microorganisms who were successfully treated with removal of the devices and intraventricular ciprofloxacin are presented. In conclusion, intraventricular ciprofloxacin can be used for treatment of central nervous system infections if the causative microorganism is sensitive to the drug and no other alternative therapy is available.

  19. RESISTANCE TO AMOXICILLIN, CLARITHROMYCIN AND CIPROFLOXACIN OF Helicobacter pylori ISOLATED FROM SOUTHERN BRAZIL PATIENTS

    Directory of Open Access Journals (Sweden)

    Simone Ulrich Picoli

    2014-06-01

    Full Text Available Introduction: Helicobacter pylori is a bacteria which infects half the world population and is an important cause of gastric cancer. The eradication therapy is not always effective because resistance to antimicrobials may occur. The aim of this study was to determine the susceptibility profile of H. pylori to amoxicillin, clarithromycin and ciprofloxacin in the population of Southern Brazil. Material and methods: Fifty four samples of H. pylori were evaluated. The antibiotics susceptibility was determined according to the guidelines of the British Society for Antimicrobial Chemotherapy and the Comité de l'Antibiogramme de la Société Française de Microbiologie. Results: Six (11.1% H. pylori isolates were resistant to clarithromycin, one (1.9% to amoxicillin and three (5.5% to ciprofloxacin. These indices of resistance are considered satisfactory and show that all of these antibiotics can be used in the empirical therapy. Conclusion: The antibiotics amoxicillin and clarithromycin are still a good option for first line anti-H. pylori treatment in the population of Southern Brazil.

  20. Antimicrobial resistance in commensal Escherichia coli in veal calves is associated with antimicrobial drug use.

    Science.gov (United States)

    Bosman, A B; Wagenaar, J A; Stegeman, J A; Vernooij, J C M; Mevius, D J

    2014-09-01

    The aim of this study was to determine the association between farm management factors, including antimicrobial drug usage, and resistance in commensal Escherichia coli isolates from the faeces of white veal calves. Ninety E. coli isolates from one pooled sample per farm (n = 48) were tested for their phenotypical resistance against amoxicillin, tetracycline, cefotaxime, ciprofloxacin and trimethoprim/sulfamethoxazole (TMP/SMX). Logistic regression analysis revealed the following risk factors (P 40 ADD/pc, tetracyclines (tetracycline, OR 13·1; amoxicillin, OR 6·5). In this study antimicrobial resistance in commensal E. coli was mainly associated with antimicrobial drug use. PMID:24152540

  1. Effect of generics on price and consumption of ciprofloxacin in primary healthcare

    DEFF Research Database (Denmark)

    Jensen, Ulrich S; Muller, Arno; Brandt, Christian T;

    2010-01-01

    ciprofloxacin and on ciprofloxacin resistance in Escherichia coli urine isolates. METHODS: We conducted a retrospective ecological study collecting monthly national data on the number of marketed versions and primary healthcare (PHC) sales of ciprofloxacin during January 1995-December 2005. Data were compared...... with a median price per defined daily dose (DDD) of ciprofloxacin during September 1999-December 2005. Yearly PHC consumption data from seven Danish counties were compared with the antimicrobial resistance profiles of PHC E. coli urine isolates. RESULTS: During 2002, the number of marketed versions...

  2. Travel to Asia and traveller's diarrhoea with antibiotic treatment are independent risk factors for acquiring ciprofloxacin-resistant and extended spectrum β-lactamase-producing Enterobacteriaceae-a prospective cohort study.

    Science.gov (United States)

    Reuland, E A; Sonder, G J B; Stolte, I; Al Naiemi, N; Koek, A; Linde, G B; van de Laar, T J W; Vandenbroucke-Grauls, C M J E; van Dam, A P

    2016-08-01

    Travel to (sub)tropical countries is a well-known risk factor for acquiring resistant bacterial strains, which is especially of significance for travellers from countries with low resistance rates. In this study we investigated the rate of and risk factors for travel-related acquisition of extended spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E), ciprofloxacin-resistant Enterobacteriaceae (CIPR-E) and carbapenem-resistant Enterobacteriaceae. Data before and after travel were collected from 445 participants. Swabs were cultured with an enrichment broth and sub-cultured on selective agar plates for ESBL detection, and on plates with a ciprofloxacin disc. ESBL production was confirmed with the double-disc synergy test. Species identification and susceptibility testing were performed with the Vitek-2 system. All isolates were subjected to ertapenem Etest. ESBL and carbapenemase genes were characterized by PCR and sequencing. Twenty-seven out of 445 travellers (6.1%) already had ESBL-producing strains and 45 of 445 (10.1%) travellers had strains resistant to ciprofloxacin before travel. Ninety-eight out of 418 (23.4%) travellers acquired ESBL-E and 130 of 400 (32.5%) travellers acquired a ciprofloxacin-resistant strain. Of the 98 ESBL-E, predominantly Escherichia coli and predominantly blaCTX-M-15, 56% (55/98) were resistant to gentamicin, ciprofloxacin and co-trimoxazole. Multivariate analysis showed that Asia was a high-risk area for ESBL-E as well as CIPR-E acquisition. Travellers with diarrhoea combined with antimicrobial use were significantly at higher risk for acquisition of resistant strains. Only one carbapenemase-producing isolate was acquired, isolated from a participant after visiting Egypt. In conclusion, travelling to Asia and diarrhoea combined with antimicrobial use are important risk factors for acquiring ESBL-E and CIPR-E. PMID:27223840

  3. Fosfomycin Resistance in Escherichia coli, Pennsylvania, USA.

    Science.gov (United States)

    Alrowais, Hind; McElheny, Christi L; Spychala, Caressa N; Sastry, Sangeeta; Guo, Qinglan; Butt, Adeel A; Doi, Yohei

    2015-11-01

    Fosfomycin resistance in Escherichia coli is rare in the United States. An extended-spectrum β-lactamase-producing E. coli clinical strain identified in Pennsylvania, USA, showed high-level fosfomycin resistance caused by the fosA3 gene. The IncFII plasmid carrying this gene had a structure similar to those found in China, where fosfomycin resistance is commonly described.

  4. Resistência a antimicrobianos de Escherichia coli isolada de dejetos suínos em esterqueiras Antibiotic-resistance of Escherichia coli isolates from stored pig slurry

    Directory of Open Access Journals (Sweden)

    F.F.P. Silva

    2008-06-01

    Full Text Available The antimicrobial resistance of 96 Escherichia coli strains isolated from a stabilization pond system on a pig-breeding farm was evaluated. Strains were tested for their resistance against 14 antimicrobial using the agar diffusion method. E. coli strains showed resistance to tetracycline (82.3%, nalidixic acid (64%, ampicilin (41%, sulfamethoxazole/trimethoprin (36%, sulfonamide (34%, cloranphenicol (274%, ciprofloxacin (19%, cefaclor (16%, streptomicyn (7.3%, neomicyn (1%, amoxacilin/ clavulanic acid (1%, and amikacin (1%. No resistance was observed to gentamicin and tobramycin, and 37.5% of E. coli strains were resistant to four or more antimicrobials. The multiresistance pattern was found in strains isolated during all sampled period. Strains showed a high variability in the antimicrobial resistance pattern.

  5. Assessment of altered binding specificity of bacteriophage for ciprofloxacin-induced antibiotic-resistant Salmonella Typhimurium.

    Science.gov (United States)

    Kim, Jeongjin; Jo, Ara; Ding, Tian; Lee, Hyeon-Yong; Ahn, Juhee

    2016-08-01

    This study describes a new effort toward understanding the interaction mechanisms between antibiotic-resistant Salmonella Typhimurium and phages. The antibiotic susceptibility, β-lactamase activity, bacterial motility, gene expression, and lytic activity were evaluated in ciprofloxacin-induced antibiotic-sensitive Salmonella Typhimurium (ASST(CIP)) and ciprofloxacin-induced antibiotic-resistant S. Typhimurium (ARST(CIP)), which were compared to the wild-type strains (ASST(WT) and ARST(WT)). The MIC values of ampicillin, norfloxacin, chloramphenicol, and tetracycline were significantly increased to > 512, 16, 16, and 256 μg/ml, respectively, in the ARST(CIP). The lowest and highest extracellular lactamase activities were observed in ASST(WT) (6.85 μmol/min/ml) and ARST(CIP) (48.83 μmol/min/ml), respectively. The acrA, lpfE, and hilA genes were significantly upregulated by more than tenfold in both ASST(CIP) and ARST(CIP). The induction of multiple antibiotic resistance resulted from the increased efflux pump activity (AcrAB-TolC). The highest phage adsorption rates were more than 95 % for ASST(WT), ASST(CIP), and ARST(WT), while the lowest adsorption rate was 52 % for ARST(CIP) at 15 min of infection. The least lytic activity of phage was 20 % against the ARST(CIP), followed by ASST(CIP) (30 %). The adsorption rate of phage against ARST(CIP) was 52 % at 15 min of infection, which resulted in the decrease in lytic activity (12 %). Understanding the interaction of phage and bacteria is essential for the practical application of phage to control and detect antibiotic-resistant bacteria. The results provide useful information for understanding the binding specificity of phages for multiple antibiotic-resistant pathogens. PMID:27000396

  6. Emerging nalidixic acid and ciprofloxacin resistance in non-typhoidal Salmonella isolated from patients having acute diarrhoeal disease

    International Nuclear Information System (INIS)

    Non-typhoidal Salmonella are one of the key etiological agents of diarrhoeal disease. The appearence of multiple drung resistance along with resistance to quinolones in this bacterium poses a serious therapeutic problem. We determined the prevalence of nalidixic acid and ciprofloxacin resistance in non-typhodial Salmonella isolated from faecal samples of patients with acute diarroheal disease attending the outpatient and inpatient department of a hospital in Saudi Arabia during the years 1999 to 2002. Non-typhodial Salmonella were isolated from faecal samples. Antimicrobial susceptibility was tested by the disc diffusion test. MICs to nalidixic acid and ciprofloxacinwere determined by the agar dilution method. During the study period , 524 strains of non-typhoidal Salmonella were isolated. Strains belonging to serogroup C1were the commonest (41.4%) followed by serogroups B and D (15.6% and 14.5%, respectively). Resistance to ampicillin was observed in 22.9% and to trimethoprim/sulphamethoxazole in 18.5%of the strains. Nalidixic acid resistance was encounterd in 9.9% and ciprofloxacin esistance in 2.3% of the strains. Resistance to nalidixic acid significantly increased from 0.1% in 1999 to 5.51% in 2002 ( p=0.0007)and ciprofloxacin resistance increased significantly from 0.1% in 1999 to 0.9% in 2002( p=0.0001). MICs to nalidixic acid and ciprofloxacin were determined among 29 nalidixic acid-resistant strains of non-typhoidal salmonella isolated during 2002. The MIC was >256 ug /ml to nalidixic acid and 8 to 16 ug/ml to ciprofloxacin. The increasing rate of antimicrobial resistance encountered among non-tyophoidal Salmonella necessiate the judicious use of these drugs in humans. Moreover, these findings support the concern that the use of quinolones in animal feed may lead to an increasein resistance and should should be restricted. (author)

  7. South Asia as a Reservoir for the Global Spread of Ciprofloxacin-Resistant Shigella sonnei: A Cross-Sectional Study

    Science.gov (United States)

    Pham Thanh, Duy; De Lappe, Niall; Cormican, Martin; Howden, Benjamin P.; Wangchuk, Sonam; Bodhidatta, Ladaporn; Nguyen Thi Nguyen, To; Thompson, Corinne N.; Phu Huong Lan, Nguyen; Voong Vinh, Phat; Ha Thanh, Tuyen; Turner, Paul; Sar, Poda; Thwaites, Guy; Thomson, Nicholas R.; Holt, Kathryn E.; Baker, Stephen

    2016-01-01

    Background Antimicrobial resistance is a major issue in the Shigellae, particularly as a specific multidrug-resistant (MDR) lineage of Shigella sonnei (lineage III) is becoming globally dominant. Ciprofloxacin is a recommended treatment for Shigella infections. However, ciprofloxacin-resistant S. sonnei are being increasingly isolated in Asia and sporadically reported on other continents. We hypothesized that Asia is a primary hub for the recent international spread of ciprofloxacin-resistant S. sonnei. Methods and Findings We performed whole-genome sequencing on a collection of 60 contemporaneous ciprofloxacin-resistant S. sonnei isolated in four countries within Asia (Vietnam, n = 11; Bhutan, n = 12; Thailand, n = 1; Cambodia, n = 1) and two outside of Asia (Australia, n = 19; Ireland, n = 16). We reconstructed the recent evolutionary history of these organisms and combined these data with their geographical location of isolation. Placing these sequences into a global phylogeny, we found that all ciprofloxacin-resistant S. sonnei formed a single clade within a Central Asian expansion of lineage III. Furthermore, our data show that resistance to ciprofloxacin within S. sonnei may be globally attributed to a single clonal emergence event, encompassing sequential gyrA-S83L, parC-S80I, and gyrA-D87G mutations. Geographical data predict that South Asia is the likely primary source of these organisms, which are being regularly exported across Asia and intercontinentally into Australia, the United States and Europe. Our analysis was limited by the number of S. sonnei sequences available from diverse geographical areas and time periods, and we cannot discount the potential existence of other unsampled reservoir populations of antimicrobial-resistant S. sonnei. Conclusions This study suggests that a single clone, which is widespread in South Asia, is likely driving the current intercontinental surge of ciprofloxacin-resistant S. sonnei and is capable of establishing

  8. Ciprofloxacin Ophthalmic

    Science.gov (United States)

    Ciprofloxacin ophthalmic solution is used to treat bacterial infections of the eye including conjunctivitis (pinkeye; infection of ... in the clear front part of the eye). Ciprofloxacin ophthalmic ointment is used to treat conjunctivitis. Ciprofloxacin ...

  9. Antimicrobial Resistance of Escherichia fergusonii Isolated from Broiler Chickens.

    Science.gov (United States)

    Simmons, Karen; Islam, M Rashedul; Rempel, Heidi; Block, Glenn; Topp, Edward; Diarra, Moussa S

    2016-06-01

    The objective of this study was to investigate the antibiotic resistance of Escherichia fergusonii isolated from commercial broiler chicken farms. A total of 245 isolates from cloacal and cecal samples of 28- to 36-day-old chickens were collected from 32 farms. Isolates were identified using PCR, and their susceptibility to 16 antibiotics was determined by disk diffusion assay. All isolates were susceptible to meropenem, amikacin, and ciprofloxacin. The most common resistances were against ampicillin (75.1%), streptomycin (62.9%), and tetracycline (57.1%). Of the 184 ampicillin-resistant isolates, 127 were investigated using a DNA microarray carrying 75 probes for antibiotic resistance genetic determinants. Of these 127 isolates, the β-lactamase blaCMY2, blaTEM, blaACT, blaSHV, and blaCTX-M-15 genes were detected in 120 (94.5%), 31 (24.4%), 8 (6.3%), 6 (4.7%), and 4 (3.2%) isolates, respectively. Other detected genes included those conferring resistance to aminoglycosides (aadA1, strA, strB), trimethoprims (dfrV, dfrA1), tetracyclines (tetA, tetB, tetC, tetE), and sulfonamides (sul1, sul2). Class 1 integron was found in 35 (27.6%) of the ampicillin-resistant isolates. However, our data showed that the tested E. fergusonii did not carry any carbapenemase blaOXA genes. Pulsed-field gel electrophoresis revealed that the selected ampicillin-resistant E. fergusonii isolates were genetically diverse. The present study indicates that the monitoring of antimicrobial-resistant bacteria should include enteric bacteria such as E. fergusonii, which could be a reservoir of antibiotic resistance genes. The detection of isolates harboring extended-spectrum β-lactamase genes, particularly blaCTX-M-15, in this work suggests that further investigations on the occurrence of such genes in broilers are warranted.

  10. Treatment failure in a typhoid patient infected with nalidixic acid resistant S. enterica serovar Typhi with reduced susceptibility to Ciprofloxacin: a case report from Cameroon

    Directory of Open Access Journals (Sweden)

    Asonganyi Etienne DN

    2005-06-01

    Full Text Available Abstract Background Fluoroquinolones or third generation cephalosporins are the drugs of choice for the treatment of typhoid fever. Treatment failure with fluoroquinolones has been reported in Asia and Europe. We report a case of ciprofloxacin treatment failure in typhoid fever in Cameroon. Case presentation A 29-year-old female patient with suspected typhoid fever from Kumba, Cameroon, yielded growth of Salmonella enterica serovar Typhi in blood culture. The isolate was resistant to nalidixic acid but sensitive to ciprofloxacin by disc diffusion test. However, the patient did not respond to treatment with ciprofloxacin, although the isolate was apparently susceptible to ciprofloxacin. Conclusion Treatment failure with ciprofloxacin in our case indicates the presence of nalidixic acid resistant S. enterica serovar Typhi (NARST with reduced susceptibility to ciprofloxacin in Cameroon (Central Africa.

  11. Attempt to develop live attenuated bacterial vaccines by selecting resistance to gossypol, proflavine hemisulfate, novobiocin, or ciprofloxacin

    Science.gov (United States)

    In an attempt to develop attenuated bacteria as potential live vaccines, four chemicals (gossypol, proflavine hemisulfate, novobiocin, and ciprofloxacin) were used to modify the following four genera of bacteria through chemical-resistance strategy: (1) Aeromonas hydrophila (9 isolates); (2) Edwards...

  12. Trends in antimicrobial susceptibility among isolates of Campylobacter species in Ireland and the emergence of resistance to ciprofloxacin.

    LENUS (Irish Health Repository)

    Lucey, B

    2012-02-03

    Measurements were made of the susceptibility to six commonly prescribed antibiotics, including erythromycin, tetracycline and ciprofloxacin, of 130 isolates of Campylobacterjejuni and 15 isolates of Campylobacter coli cultured from human and poultry sources during 2000. The results were compared with the results from a collection of strains isolated between 1996 and 1998. The levels of resistance to erythromycin remained low, 2 per cent and 4.4 per cent for the human and poultry isolates, respectively. Resistance to tetracycline had increased to 31 per cent and 24.4 per cent from 13.9 per cent and 18.8 per cent for the human and poultry isolates, respectively. However, the resistance to ciprofloxacin of the strains isolated during 2000 had increased to 30 per cent, whereas between 1996 and 1998 there had been no resistance to this agent among human isolates, and only 3.1 per cent resistance among poultry isolates. The molecular basis for this resistance has been shown to be the result of a single amino acid substitution, Thr-86-Ile, in the gyrA subunit of DNA gyrase in Cjejuni. A subset of 59 isolates was tested by molecular methods and all of the 25 phenotypically resistant isolates possessed this substitution. None of the human isolates had been treated with ciprofloxacin before their laboratory isolation.

  13. Antimalarial therapy selection for quinolone resistance among Escherichia coli in the absence of quinolone exposure, in tropical South America.

    Directory of Open Access Journals (Sweden)

    Ross J Davidson

    Full Text Available BACKGROUND: Bacterial resistance to antibiotics is thought to develop only in the presence of antibiotic pressure. Here we show evidence to suggest that fluoroquinolone resistance in Escherichia coli has developed in the absence of fluoroquinolone use. METHODS: Over 4 years, outreach clinic attendees in one moderately remote and five very remote villages in rural Guyana were surveyed for the presence of rectal carriage of ciprofloxacin-resistant gram-negative bacilli (GNB. Drinking water was tested for the presence of resistant GNB by culture, and the presence of antibacterial agents and chloroquine by HPLC. The development of ciprofloxacin resistance in E. coli was examined after serial exposure to chloroquine. Patient and laboratory isolates of E. coli resistant to ciprofloxacin were assessed by PCR-sequencing for quinolone-resistance-determining-region (QRDR mutations. RESULTS: In the very remote villages, 4.8% of patients carried ciprofloxacin-resistant E. coli with QRDR mutations despite no local availability of quinolones. However, there had been extensive local use of chloroquine, with higher prevalence of resistance seen in the villages shortly after a Plasmodium vivax epidemic (p<0.01. Antibacterial agents were not found in the drinking water, but chloroquine was demonstrated to be present. Chloroquine was found to inhibit the growth of E. coli in vitro. Replica plating demonstrated that 2-step QRDR mutations could be induced in E. coli in response to chloroquine. CONCLUSIONS: In these remote communities, the heavy use of chloroquine to treat malaria likely selected for ciprofloxacin resistance in E. coli. This may be an important public health problem in malarious areas.

  14. Antimicrobial resistance in community and nosocomial Escherichia coli urinary tract isolates, London 2005 – 2006

    OpenAIRE

    Wareham David W.; Krahe Daniel; Bean David C

    2008-01-01

    Abstract Background Escherichia coli is the commonest cause of community and nosocomial urinary tract infection (UTI). Antibiotic treatment is usually empirical relying on susceptibility data from local surveillance studies. We therefore set out to determine levels of resistance to 8 commonly used antimicrobial agents amongst all urinary isolates obtained over a 12 month period. Methods Antimicrobial susceptibility to ampicillin, amoxicillin/clavulanate, cefalexin, ciprofloxacin, gentamicin, ...

  15. Rapid spread of Neisseria gonorrhoeae ciprofloxacin resistance due to a newly introduced resistant strain in Nuuk, Greenland, 2012–2015: a community-based prospective cohort study

    Science.gov (United States)

    Pedersen, Michael Lynge; Poulsen, Peter; Berthelsen, Lene; Nørgaard, Christina; Hoffmann, Steen; Jensen, Jørgen Skov

    2016-01-01

    Objectives To determine the antimicrobial susceptibility and genotype distribution of Neisseria gonorrhoeae strains isolated from a cohort of patients in Nuuk, Greenland in order to assess the risk of rapid spread in the event of introduction of new strains. Methods Gonococcal isolates (n=102) obtained from a prospective cohort study of ciprofloxacin resistance were collected between March 2012 and February 2013. Etest minimal inhibitory concentrations (MICs) were determined for ciprofloxacin, azithromycin, ceftriaxone, penicillin, tetracycline, spectinomycin and gentamicin. All isolates were subjected to molecular typing using N. gonorrhoeae multiantigen sequence typing (NG-MAST). After the introduction of a ciprofloxacin-resistant strain in early 2014, an additional 18 isolates were characterised. Results During the study period, all 102 isolates were fully susceptible to ciprofloxacin (≤0.03 mg/L), azithromycin, spectinomycin, gentamicin and ceftriaxone. 10 different NG-MAST types circulated in Nuuk but 7 were found as single isolates, and 3 of the 7 belonged to 1 of the 3 major genogroups (G210, G9816 and G9817) together comprising 96% of the 102 isolates. ST210 accounted for 55% of the 102 strains. The newly introduced ciprofloxacin resistant strain belonged to ST2400 and dominated the population with 59% resistant strains within 6 months after its introduction. All G2400 strains had MICs≥2 mg/L. Conclusions Introduction of a ciprofloxacin-resistant strain into a very homogeneous N. gonorrhoeae population led to an explosive spread of the resistant clone, probably as a result of large sexual networks suggested by the strain homogeneity. Careful surveillance of antimicrobial susceptibility is essential to avoid widespread treatment failure in closed populations. PMID:27577587

  16. RESISTANCE PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGHE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-02-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests.65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics asfeed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials.

  17. ANTIMICROBIAL RESISTANT PATTERN OF FECAL ESCHERICHIA COLI IN SELECTED BROILER FARMS OF EASTERN HARARGE ZONE, ETHIOPIA

    Directory of Open Access Journals (Sweden)

    Tesfaheywet Zeryehun

    2013-12-01

    Full Text Available A study was conducted to determine the pattern of antimicrobial resistance in Escherichia coli isolated from Cloacal swab of broiler chickens in selected farms of Eastern Harrarge zone of Ethiopia. Isolation and identification of Escherichia coli were done by using enrichment media, selective media, and biochemical tests. 65 selected isolates were subjected to 9 antimicrobial agents to determine their resistance by the disk diffusion method. Accordingly, the resistance of E.coli was tetracycline (90%, streptomycin (78%, ampicillin (60%, amoxicillin (56%, erythromycin (45%, ciprofloxacin (38%, and chloramphenicol (15%. None of the isolates showed resistance to gentamicin. Sensitivity was observed in case of 80%, 77%, 44%, 32%, 26%, 20%, 20%, 15%, and 10% of the isolates for chloramphenicol, gentamicin, ciprofloxacin, amoxicillin, ampicillin, streptomycin, erythromycin, and tetracycline, respectively. Intermediate resistance/susceptibility was recorded for 5-35% of the isolates. 92.3% of the isolates tested showed multidrug resistance for 2 or more antimicrobials and the highest levels (18.5% of multidrug-resistant E. coli were observed for 3 antimicrobials accounting 7.7% for tetracycline-ampicillin-streptomycin and 10.8% for tetracycline-ampicillin-amoxicillin. This study showed resistance against the antibiotics that are commonly used in poultry. Furthermore, it was concluded that gentamicin, chloramphenicole and ciproflaxin will be the first drugs of choice to resist infections caused by E. coli in chicken in Ethiopia. These findings confirm significant increase in the incidence of antimicrobial resistance in the E. coli isolates which is most probably due to increased use of antibiotics as feed additives for growth promotion and prevention of diseases and use of inappropriate antibiotics for treatment of diseases. Hence, excess or abusive use of antimicrobials should be guarded through judicious application of antimicrobials

  18. Comparative Analysis of Quinolone Resistance in Clinical Isolates of Klebsiella pneumoniae and Escherichia coli from Chinese Children and Adults

    Directory of Open Access Journals (Sweden)

    Ying Huang

    2015-01-01

    Full Text Available The objective of this study was to compare quinolone resistance and gyrA mutations in clinical isolates of Klebsiella pneumoniae and Escherichia coli from Chinese adults who used quinolone in the preceding month and children without any known history of quinolone administration. The antimicrobial susceptibilities of 61 isolates from children and 79 isolates from adults were determined. The mutations in the quinolone resistance-determining regions in gyrA gene were detected by PCR and DNA sequencing. Fluoroquinolone resistance and types of gyrA mutations in isolates from children and adults were compared and statistically analyzed. No significant differences were detected in the resistance rates of ciprofloxacin and levofloxacin between children and adults among isolates of the two species (all P>0.05. The double mutation Ser83→Leu + Asp87→Asn in the ciprofloxacin-resistant isolates occurred in 73.7% isolates from the children and 67.9% from the adults, respectively (P=0.5444. Children with no known history of quinolone administration were found to carry fluoroquinolone-resistant Enterobacteriaceae isolates. The occurrence of ciprofloxacin resistance and the major types of gyrA mutations in the isolates from the children were similar to those from adults. The results indicate that precautions should be taken on environmental issues resulting from widespread transmission of quinolone resistance.

  19. Antimicrobial action of zinc oxide nanoparticles in combination with ciprofloxacin and ceftazidime against multidrug-resistant Acinetobacter baumannii.

    Science.gov (United States)

    Ghasemi, F; Jalal, R

    2016-09-01

    Acinetobacter baumannii is a serious concern amongst hospitalised patients worldwide and its resistance to antibiotics has emerged as a threat to public health in recent years. Metal oxide nanoparticles were found to be effective for overcoming bacterial resistance owing to their antibacterial activities. The aim of this study was to investigate the combined effects of zinc oxide nanoparticles (ZnO-NPs) and the conventional antibiotics ciprofloxacin and ceftazidime as well as their mechanisms of action against resistant A. baumannii. ZnO-NPs were prepared by the solvothermal method and were characterised by various methods. Broth microdilution and disk diffusion methods were used to determine the antibacterial activities of ciprofloxacin and ceftazidime antibiotics in the absence and presence of a subinhibitory concentration of ZnO-NPs. The mechanism of action of ZnO-NPs alone and in combination with these antibiotics was assessed by flow cytometry, DNA extraction, fluorescence and scanning electron microscopy. The results showed that the antibacterial activities of both antibiotics increased in the presence of a subinhibitory concentration of ZnO-NPs. Combination of ZnO-NPs with antibiotics increased the uptake of antibiotics and changed the bacterial cells from rod to cocci forms. Bacterial filamentation was also observed and exhibited no DNA fragmentation. In conclusion, the results of this study indicate that ZnO-NPs potentiate the antimicrobial action of ciprofloxacin and ceftazidime. A mechanism is proposed to explain this phenomenon. PMID:27530853

  20. Molecular epidemiology of ciprofloxacin-resistant extended-spectrum β-lactamase-producing Klebsiella pneumoniae in Taiwan.

    Science.gov (United States)

    Lin, Chi-Jan; Siu, L Kristopher; Ma, Ling; Chang, Ya-Ting; Lu, Po-Liang

    2012-02-01

    Fluoroquinolone resistance in extended-spectrum β-lactamases (ESBL)-producing isolates results in very few antimicrobial treatment options. In Taiwan's Surveillance of Antimicrobial Resistance (TSAR) III program, 124 (52.8%) cases of ESBL-producing Klebsiella pneumoniae (ESBL-KP) were resistant to ciprofloxacin. The prevalence of plasmid-mediated quinolone resistance (PMQR) determinants and chromosomal quinolone resistance-determining regions (QRDR) of gyrA and parC genes among ESBL-KP isolates was assessed via PCR sequencing. Chromosomal QRDR mutations were present in most of the 123 (96.8%) cases of ciprofloxacin-resistant ESBL-KP isolates. Sixty-six (53.2%) isolates had at least one PMQR gene. qnrB2, qnrB4, and qnrS1 were detected in 26, 19, and 13 isolates, respectively, whereas qnrA, qnrC, and qnrD were not detected. ESBL genes were transferable via conjugation with either aac(6')Ib-cr or qnrB in 63.6% of the isolates carrying PMQR genes. QnrB was associated with either CTX-M-15 or SHV-12, and aac(6')Ib-cr was linked to CTX-M-3 or CTX-M-14 in plasmids. qnrS did not co-transfer with ESBL genes. Clonal spread of PMQR genes harboring ESBL-KP isolates was observed in three hospitals. QnrA, which is common in Asia, was unexpectedly absent in ESBL-KP in Taiwan. Aside from transmission via clonal spread for ciprofloxacin-resistant ESBL-KP, concomitant transference of PMQR genes with either bla(CTX-M) or bla(SHV) via plasmid was common. PMID:22022870

  1. Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations in quinolone-resistant Escherichia coli isolated from humans and swine in Denmark

    DEFF Research Database (Denmark)

    Cavaco, Lina; Frimodt-Møller, Niels; Hasman, Henrik;

    2008-01-01

    Prevalence of quinolone resistance mechanisms and associations to minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were investigated in 124 Escherichia coli isolated from humans (n = 85) and swine (n = 39) in Denmark. The collection included 59 high-level CIP......-resistant isolates (MIC >= 4) from human (n = 51) and pig origin (n = 8) and 65 low-level CIP-resistant isolates (MIC >= 0.125) from human (n = 34) and pig origin (n = 31). Resistance by target modification was screened by PCR amplification and sequencing, of the quinolone resistance determining regions (QRDRs) of......A and qnrS genes conferring quinolone resistance by target protection were detected in two human low-level CIP-resistant isolates that did not display NAL resistance. As expected, target mutation in QRDRs was the most prevalent mechanism of quinolone resistance. This mechanism was complemented by efflux...

  2. In Vitro Antimicrobial Resistance of Urinary Escherichia coli Isolates among U.S. Outpatients from 2000 to 2010

    OpenAIRE

    Sanchez, Guillermo V.; Master, Ronald N; Karlowsky, James A.; Bordon, Jose M.

    2012-01-01

    This study examines in vitro antimicrobial resistance data from Escherichia coli isolates obtained from urine samples of U.S. outpatients between 2000 and 2010 using The Surveillance Network (TSN). Antimicrobial susceptibility results (n = 12,253,679) showed the greatest increases in E. coli resistance from 2000 to 2010 for ciprofloxacin (3% to 17.1%) and trimethoprim-sulfamethoxazole (TMP-SMX) (17.9% to 24.2%), whereas nitrofurantoin (0.8% to 1.6%) and ceftriaxone (0.2% to 2.3%) showed minim...

  3. Increasing resistance to ciprofloxacin and other antibiotics in Neisseria gonorrhoeae from East Java and Papua, Indonesia, in 2004 - implications for treatment.

    Science.gov (United States)

    Sutrisna, A; Soebjakto, O; Wignall, F S; Kaul, S; Limnios, E A; Ray, S; Nguyen, N-L; Tapsall, J W

    2006-12-01

    We examined gonococci isolated in 2004, in East Java and Papua, Indonesia, to review the suitability of ciprofloxacin-based and other treatment regimens. Gonococci from the two provinces were tested in Sydney for susceptibility to penicillin, tetracycline, spectinomycin, ceftriaxone, ciprofloxacin, gentamicin, azithromycin and rifampicin. Of 163 gonococcal isolates from East Java (91) and Papua (72), 120 (74%) of gonococci, 62 (68%) and 58 (80%) from East Java and Papua, respectively, were penicillinase-producing gonococci and 162 displayed high-level tetracycline resistance. Eighty-seven isolates (53%) were ciprofloxacin resistant, 44 (48%) from East Java and 43 (60%) from Papua. All isolates were sensitive to cefixime/ceftriaxone, spectinomycin and azithromycin. Minimum inhibitory concentrations of gentamicin were in the range 0.05-8 mg/L. Sixty-nine gonococci (42%) showed combined resistance, to penicillin, tetracycline and quinolones. Quinolone resistance has now reached unacceptable levels, and their use for the treatment of gonorrhoea in Indonesia should be reconsidered.

  4. Sensitivity of antibiotic resistant and antibiotic susceptible Escherichia coli, Enterococcus and Staphylococcus strains against ozone.

    Science.gov (United States)

    Heß, Stefanie; Gallert, Claudia

    2015-12-01

    Tolerance of antibiotic susceptible and antibiotic resistant Escherichia coli, Enterococcus and Staphylococcus strains from clinical and wastewater samples against ozone was tested to investigate if ozone, a strong oxidant applied for advanced wastewater treatment, will affect the release of antibiotic resistant bacteria into the aquatic environment. For this purpose, the resistance pattern against antibiotics of the mentioned isolates and their survival after exposure to 4 mg/L ozone was determined. Antibiotic resistance (AR) of the isolates was not correlating with higher tolerance against ozone. Except for ampicillin resistant E. coli strains, which showed a trend towards increased resistance, E. coli strains that were also resistant against cotrimoxazol, ciprofloxacin or a combination of the three antibiotics were similarly or less resistant against ozone than antibiotic sensitive strains. Pigment-producing Enterococcus casseliflavus and Staphylococcus aureus seemed to be more resistant against ozone than non-pigmented species of these genera. Furthermore, aggregation or biofilm formation apparently protected bacteria in subsurface layers from inactivation by ozone. The relatively large variance of tolerance against ozone may indicate that resistance to ozone inactivation most probably depends on several factors, where AR, if at all, does not play a major role.

  5. Echinoderms from Azores islands: an unexpected source of antibiotic resistant Enterococcus spp. and Escherichia coli isolates.

    Science.gov (United States)

    Marinho, Catarina; Silva, Nuno; Pombo, Sofia; Santos, Tiago; Monteiro, Ricardo; Gonçalves, Alexandre; Micael, Joana; Rodrigues, Pedro; Costa, Ana Cristina; Igrejas, Gilberto; Poeta, Patrícia

    2013-04-15

    The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp. and Escherichia coli, isolated from a total of 250 faecal samples of echinoderms collected from Azorean waters (Portugal). A total of 144 enterococci (120 Enterococcus faecium, 14 E. hirae, 8 E. faecalis, 2 E. gallinarum) and 10 E. coli were recovered. High percentages of resistance in enterococci were found for erythromycin, ampicillin, tetracyclin and ciprofloxacin. The erm(A) or erm(B), tet(M) and/or tet(L), vat(D), aac(6')-aph(2″) and aph(3')-IIIa genes were found in isolates resistant to erythromycin, tetracycline, quinupristin/dalfopristin, high-level gentamicin and high-level kanamycin, respectively. Resistance in E. coli isolates was detected for streptomycin, amikacin, tetracycline and tobramycin. The aadA gene was found in streptomycin-resistant isolates and tet(A)+tet(B) genes in tetracycline-resistant isolates. The data recovered are essential to improve knowledge about the dissemination of resistant strains through marine ecosystems and the possible implications involved in transferring these resistances either to other animals or to humans. PMID:23419753

  6. Induction of Fibronectin Adhesins in Quinolone-Resistant Staphylococcus aureus by Subinhibitory Levels of Ciprofloxacin or by Sigma B Transcription Factor Activity Is Mediated by Two Separate Pathways

    OpenAIRE

    Li, Dongmei; Renzoni, Adriana; Estoppey, Tristan; Bisognano, Carmelo; Francois, Patrice; Kelley, William L; Lew, Daniel P.; Schrenzel, Jacques; Vaudaux, Pierre

    2005-01-01

    We recently reported on the involvement of a RecA-LexA-dependent pathway in the ciprofloxacin-triggered upregulation of fibronectin-binding proteins (FnBPs) by fluoroquinolone-resistant Staphylococcus aureus. The potential additional contribution of the transcription factor sigma B (SigB) to the ciprofloxacin-triggered upregulation of FnBPs was studied in isogenic mutants of fluoroquinolone-resistant strain RA1 (a topoisomerase IV gyrase double mutant of S. aureus NCTC strain 8325), which exh...

  7. Novel gyrA point mutation in a strain of Escherichia coli resistant to fluoroquinolones but not to nalidixic acid.

    OpenAIRE

    Cambau, E.; Bordon, F; Collatz, E; Gutmann, L

    1993-01-01

    We have previously described a clinical isolate of Escherichia coli (Q2) that is highly resistant to fluoroquinolones (MIC of ciprofloxacin, 16 micrograms/ml) but susceptible to nalidixic acid (MIC of nalidixic acid, 4 micrograms/ml) (N. Moniot-Ville, J. Guibert, N. Moreau, J.F. Acar, E. Collatz, and L. Gutmann, Antimicrob. Agents Chemother. 35:519-523, 1991). Transformation of strain Q2 with a plasmid carrying the wild-type gyrA gene from E. coli K-12(pAFF801) resulted in a 32-fold decrease ...

  8. Rapid change in the ciprofloxacin resistance pattern among Neisseria gonorrhoeae strains in Nuuk, Greenland: time to reconsider preventive and treatment strategies

    Directory of Open Access Journals (Sweden)

    Anne Skjerbæk Rolskov

    2015-05-01

    Full Text Available Objectives: Sexually transmitted infections (STIs, including infections with Neisseria gonorrhoeae (GC, are highly incident in Greenland. Since January 2011, GC testing has been performed on urine with nucleic acid amplification tests (NAATs by strand displacement amplification (Becton Dickinson ProbeTec. Monitoring of GC antibiotic susceptibility by culture was introduced in Nuuk in 2012. Until 2014, no cases of ciprofloxacin-resistant GC strains were reported. In this paper, we report the finding of ciprofloxacin-resistant GC and describe the most recent incidence of GC infections in Greenland. Methods: The number of urine NAATs and culture-positive swabs from January to October 2014 were obtained from the Central Laboratory at Queens Ingrid's Hospital in Nuuk and stratified on gender, place and period of testing. Incidence rates were estimated as number of urine NAAT * (12/10 per 100,000 inhabitants. Men in Nuuk with a positive NAAT for GC were encouraged to provide a urethral swab for culture and susceptibility testing. Results: From January to October 2014, a total of 5,436 urine GC NAATs were performed on patients from Nuuk and 9,031 from the rest of Greenland. Of these, 422 (8% and 820 (9% were positive, respectively. From January to August, 6 (15% cultures from Nuuk were ciprofloxacin resistant while in September and October, 26 (59% were ciprofloxacin resistant (p<0.01. In total, 35 (40% of 88 culture-positive isolates showed ciprofloxacin resistance. GC incidence in Nuuk was 3,017 per 100,000 inhabitants per year, compared to 2,491 per 100,000 inhabitants per year in the rest of Greenland. Conclusion: Within a short period, a rapid and dramatic change in ciprofloxacin susceptibility among GC strains isolated in Nuuk was documented and recommendation for first line treatments has changed. Continued monitoring and rethinking of primary and secondary preventive initiatives is highly recommended in this high GC incidence setting.

  9. Molecular characterization of antimicrobial resistance in enterococci and Escherichia coli isolates from European wild rabbit (Oryctolagus cuniculus).

    Science.gov (United States)

    Silva, Nuno; Igrejas, Gilberto; Figueiredo, Nicholas; Gonçalves, Alexandre; Radhouani, Hajer; Rodrigues, Jorge; Poeta, Patrícia

    2010-09-15

    A total of 44 Escherichia coli and 64 enterococci recovered from 77 intestinal samples of wild European rabbits in Portugal were analyzed for resistance to antimicrobial agents. Resistance in E. coli isolates was observed for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, gentamicin, tobramycin, nalidixic acid, ciprofloxacin and chloramphenicol. None of the E. coli isolates produced extended-spectrum beta-lactamases (ESBLs). The bla(TEM), aadA, aac(3)-II, tet(A) and/or tet(B), and the catA genes were demonstrated in all ampicillin, streptomycin, gentamicin, tetracycline, and chloramphenicol-resistant isolates respectively, and the sul1 and/or sul2 and/or sul3 genes in 4 of 5 sulfamethoxazole/trimethoprim resistant isolates. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (39 isolates), followed by E. faecium (21 isolates) and E. hirae (4 isolates). More than one-fourth (29.7%) of the isolates were resistant to tetracycline; 20.3% were resistant to erythromycin, 14.1% were resistant to ciprofloxacin and 10.9% were resistant to high-level-kanamycin. Lower level of resistance (quinupristin/dalfopristin and high-level-gentamicin, -streptomycin. No vancomycin-resistance was detected in the enterococci isolates. Resistance genes detected included aac(6')-aph(2''), ant(6)-Ia, tet(M) and/or tet(L) in all gentamicin, streptomycin and tetracycline-resistant isolates respectively. The aph(3')-IIIa gene was detected in 6 of 7 kanamycin-resistant isolates, the erm(B) gene in 11 of 13 erythromycin-resistant isolates and the vat(D) gene in the quinupristin/dalfopristin-resistant E. faecium isolate. This survey showed that faecal bacteria such as E. coli and enterococci of wild rabbits could be a reservoir of antimicrobial resistance genes. PMID:20624632

  10. Antibiotic Resistance of Escherichia Coli Isolated From Poultry and Poultry Environment of Bangladesh

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    Muhammad A. Akond

    2009-01-01

    Full Text Available Problem statement: Increased emergence in microbial resistance to antibiotics is a growing problem in Bangladesh, a tropical country with a large agrarian population having limited medical facilities. Wide spread use of antimicrobials in poultry farming here is a concern of multi-drug microbial resistance development that can potentially be transmitted to human pathogens even from non-pathogenic carrier strains. Attempt was made to assess drug susceptibility in Escherichia coli from poultry sources of Bangladesh. Approach: Eighty selected strains isolated from poultry sources were thoroughly characterized by standard cultural and biochemical tests followed by final identification using latex agglutination test of polyvalent anti-sera, from which 50 were tested for susceptibility to 13 antibiotics following disk diffusion method. Results: 145 (58%, out of total 250, were found positive for E. coli. 52-88% of tested E. coli strains from poultry sources were found resistant to Penicillin, Ciprofloxacin, Riphampicin, Kanamycin, Streptomycin, Cefixine, Erythromycin, Ampicillin, Tetracycline, and 20% strains showed resistance to both Chloramphenicol and Neomycin. No strains showed resistance to Norfloxacin and Gentamicin. Sensitivity was recorded in case of 60-86% strains to Norfloxacin, Gentamicin, Chloramphenicol, and Neomycin; and 26-36% strains against Tetracycline, Streptomycin, and Ampicillin. Intermediate resistance/ susceptibility to various antibiotics were observed for 12-36% Escherichia coli strains. Both, resistance and susceptibility were exhibited against Chloramphenicol, Ampicillin, Gentamicin, Neomycin, Tetracycline, Streptomycin and Norfloxacin. Multi drug resistance was found in case of 6-10 antibiotics for all strains tested. Conclusion: Further study is required on the role of poultry borne bacteria as vectors in transmitting drug resistance. Attention is to be paid for personnel hygiene in processing and handling of poultry and

  11. The worldwide spread of ciprofloxacin-resistant Shigella sonnei among HIV-infected men who have sex with men, Taiwan.

    Science.gov (United States)

    Chiou, C-S; Izumiya, H; Kawamura, M; Liao, Y-S; Su, Y-S; Wu, H-H; Chen, W-C; Lo, Y-C

    2016-04-01

    Ciprofloxacin-resistant shigellosis outbreaks among men who have sex with men (MSM) have not been reported in Asia. During 3 March to 6 May 2015, the Notifiable Disease Surveillance System detected nine non-imported Shigella sonnei infections among human immunodeficiency virus (HIV) -infected Taiwanese MSM. We conducted a molecular epidemiological investigation using a 1 : 5 matched case-control study and laboratory characterizations for the isolates. Of the nine patients, four reported engagement in oral-anal sex before illness onset. Shigellosis was associated with a syphilis report within 12 months (adjusted odds ratio (aOR) 8.6; 95% CI 1.05-70.3) and no HIV outpatient follow-up within 12 months (aOR 22.3; 95% CI 2.5-201). Shigella sonnei isolates from the nine patients were all ciprofloxacin-resistant and the resistance was associated with S83L and D87G mutations in gyrA and S80I mutation in parC. The nine outbreak isolates were discriminated into two closely related pulsed-field gel electrophoresis (PFGE) genotypes and seven 8-locus multilocus variable-number tandem repeat analysis (MLVA8) types that suggest multiple sources of infections for the outbreak and possible under-recognition of infection among Taiwanese MSM. The outbreak isolates were characterized to be variants of the intercontinentally transmitted SS18.1 clone, which falls into the globally prevalent phylogenetic sub-lineage IIIb. Inter-database pattern similarity searching indicated that the two PFGE genotypes had emerged in the USA and Japan. The epidemiological characteristics of this outbreak suggest roles of risky sexual behaviours or networks in S. sonnei transmission. We urge enhanced surveillance and risk-reduction interventions regionally against the interplay of HIV and shigellosis among MSM. PMID:26806133

  12. Antibiotic resistance and plasmids carriage among Escherichia coli isolates from chicken meat in Malaysia

    International Nuclear Information System (INIS)

    One hundred and thirty-one Escherichia coli isolates from raw chicken meat were tested for antibiotic susceptibility to twelve antibiotics, namely ampicillin 10μg, cefoparazone 30μg, cephradine 30μg, ciprofloxacin 5μg, chloramphenicol 30μg, enrofloxacin 5μg, erythromycin 15μg, kanamycin 30μg, nalidixic acid 30μg, tetracycline 30μg, trimethoprim 5μg, and vancomycin 30μg. The plasmid isolation was carried out according to the method described by Maniatis et al, with modifications as in the protocol provided by Taq Dye Deoxy Terminator Cycle Sequencing Kit (ABI P/ N 401150). The newly modified method is a mini alkaline-lysis / PGE precipitation procedure and easy to perform on large numbers of samples. The graphical method of relating the logarithm of the molecular weight of a DNA molecule (log C) to its electrophoretic mobility (m) in gels was used to determine the molecular weight of plasmid. Plasmids of known molecular weight from E. coli V517 were used as standards for calibrating the size of plasmid DNA molecules. In this study DNA fragments are referred to as plasmids. In all Escherichia coli isolates resistance to ampicillin (96.2%), cefoperazone (83.3%), cephradine (93.9%), ciprofloxacin (78.0%), chloramphenical (75.6%), enrofloxacin (72.0%), erythromycin (84.0%), kanamycin (50.8%), nalidixic acid (94.7%), tetracycline (90.2%), trimethoprim (94.7%) and vancomycin (100%) was observed (Table I). Plasmid occurrence rates of 81.7% were observed among E. coli isolates from the chicken meat. The number of plasmids ranged from 0 to 8 and the sizes of plasmids ranged from 1.2 MDa to 118.6 MDa. Plasmids were detected in 93.8% of E. coli isolates that were resistant to all 12 antibiotics and in 90.5% of E. coli isolates resistant to 11 antibodies (Table II). Three (2.8%) E. coli isolates harboured 8 plasmids and showed resistant to 12 antibiotics (Table III). The antibiotic resistance among the E. coli isolates in this study was compared and it was found a

  13. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries

    Science.gov (United States)

    Nygaard Jensen, Annette; Kerouanton, Annaelle; Cibin, Veronica; Barco, Lisa; Denis, Martine; Aabo, Sören

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC) of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET) resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance. PMID:27362262

  14. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries.

    Directory of Open Access Journals (Sweden)

    Julia Österberg

    Full Text Available Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance.

  15. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries.

    Science.gov (United States)

    Österberg, Julia; Wingstrand, Anne; Nygaard Jensen, Annette; Kerouanton, Annaelle; Cibin, Veronica; Barco, Lisa; Denis, Martine; Aabo, Sören; Bengtsson, Björn

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC) of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET) resistant E. coli in colon content and/or faeces from individual pigs was determined. In all four countries the percentage resistance to ampicillin, streptomycin, sulphonamides or trimethoprim was significantly lower in E. coli from organic pigs. In France and Italy, the percentage of isolates resistant to chloramphenicol, ciprofloxacin, nalidixic acid or gentamicin was also significantly lower in the E. coli from organic pigs. Resistance to cefotaxime, was not found in any country. The percentage of E. coli isolates resistant to TET as well as the proportion of TET-resistant E. coli was significantly lower in organic than in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions in Sweden and Denmark compared to France and Italy. The study shows that in each of the four countries resistance in intestinal E. coli was less common in organic than in conventional pigs, but that there were also large differences in resistance between countries within each production type, indicating that both country- and production-specific factors influence the occurrence of resistance. PMID:27362262

  16. Antimicrobial resistance in community and nosocomial Escherichia coli urinary tract isolates, London 2005 – 2006

    Directory of Open Access Journals (Sweden)

    Wareham David W

    2008-06-01

    Full Text Available Abstract Background Escherichia coli is the commonest cause of community and nosocomial urinary tract infection (UTI. Antibiotic treatment is usually empirical relying on susceptibility data from local surveillance studies. We therefore set out to determine levels of resistance to 8 commonly used antimicrobial agents amongst all urinary isolates obtained over a 12 month period. Methods Antimicrobial susceptibility to ampicillin, amoxicillin/clavulanate, cefalexin, ciprofloxacin, gentamicin, nitrofurantoin, trimethoprim and cefpodoxime was determined for 11,865 E. coli urinary isolates obtained from community and hospitalised patients in East London. Results Nitrofurantoin was the most active agent (94% susceptible, followed by gentamicin and cefpodoxime. High rates of resistance to ampicillin (55% and trimethoprim (40%, often in combination were observed in both sets of isolates. Although isolates exhibiting resistance to multiple drug classes were rare, resistance to cefpodoxime, indicative of Extended spectrum β-lactamase production, was observed in 5.7% of community and 21.6% of nosocomial isolates. Conclusion With the exception of nitrofurantoin, resistance to agents commonly used as empirical oral treatments for UTI was extremely high. Levels of resistance to trimethoprim and ampicillin render them unsuitable for empirical use. Continued surveillance and investigation of other oral agents for treatment of UTI in the community is required.

  17. Investigation of antimicrobial resistance in Escherichia coli and enterococci isolated from Tibetan pigs.

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    Peng Li

    Full Text Available OBJECTIVES: This study investigated the antimicrobial resistance of Escherichia coli and enterococci isolated from free-ranging Tibetan pigs in Tibet, China, and analyzed the influence of free-ranging husbandry on antimicrobial resistance. METHODS: A total of 232 fecal samples were collected from Tibetan pigs, and the disk diffusion method was used to examine their antimicrobial resistance. Broth microdilution and agar dilution methods were used to determine minimum inhibitory concentrations for antimicrobial agents for which disks were not commercially available. RESULTS: A total of 129 E. coli isolates and 84 Enterococcus isolates were recovered from the fecal samples. All E. coli isolates were susceptible to amoxicillin/clavulanic acid, and 40.4% were resistant to tetracycline. A small number of isolates were resistant to florfenicol (27.9%, ampicillin (27.9%, sulfamethoxazole/trimethoprim (19.4%, nalidixic acid (19.4%, streptomycin (16.2% and ceftiofur (10.9%, and very low resistance rates to ciprofloxacin (7.8%, gentamicin (6.9%, and spectinomycin (2.3% were observed in E. coli. All Enterococcus isolates, including E. faecium, E. faecalis, E. hirae, and E. mundtii, were susceptible to amoxicillin/clavulanic acid and vancomycin, but showed high frequencies of resistance to oxacillin (92.8%, clindamycin (82.1%, tetracycline (64.3%, and erythromycin (48.8%. Resistance rates to florfenicol (17.9%, penicillin (6.0%, ciprofloxacin (3.6%, levofloxacin (1.2%, and ampicillin (1.2% were low. Only one high-level streptomycin resistant E. faecium isolate and one high-level gentamicin resistant E. faecium isolate were observed. Approximately 20% and 70% of E. coli and Enterococcus isolates, respectively, were defined as multidrug-resistant. CONCLUSIONS: In this study, E. coli and Enterococcus isolated from free-ranging Tibetan pigs showed relatively lower resistance rates than those in other areas of China, where more intensive farming practices are

  18. Antimicrobial activity and synergism of Sami-Hyanglyun-Hwan with ciprofloxacin against methicillin-resistant Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    Jang-Gi; Choi; Ji-Young; Choi; Su-Hyun; Mun; Ok-Hwa; Kang; Preeti; Bharaj; Dong-Won; Shin; Myong-Soo; Chong; Dong-Yeul; Kwon

    2015-01-01

    Objective: To investigate the antibacterial activity of SHHextracted with either water or ethanol against methicillin-resistant Staphylococcus aureus(MRSA) and combinatory antimicrobial effect with ciprofloxacin(CIP) by time kill assay and checkerboard dilution test. Methods: The antibacterial activity determined by broth dilution method indicated that the antibacterial activity of Sami-Hyanglyun-Hwan(SHH) water extract(SHHW) and SHH ethanol extract(SHHE) ranged from 250 to 2000 μg/m L and 125 to 1000 μg/m L against MRSA, respectively. Results: In the checkerboard method, the combinations of SHHE with CIP had a partial synergistic or synergistic effect against MRSA. The time-kill curves showed that a combined SHHE and CIP treatment reduced the bacterial counts dramatically after 24 h. Conclusions: The present study demonstrates the therapeutic ability of SHHE against MRSA infections.

  19. Genetic characterization of fluoroquinolone-resistant Escherichia coli associated with bovine mastitis in India

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    Sangeetha Balakrishnan

    2016-07-01

    Full Text Available Aim: The present study was undertaken to characterize the mutation in gyrA (DNA gyrase and parC (topoisomerase IV genes responsible for fluoroquinolone resistance in Escherichia coli isolates associated with the bovine mastitis. Materials and Methods: A total of 92 milk samples from bovine mastitis cases were sampled in and around Puducherry (Southern India. Among these samples, 30 isolates were bacteriologically characterized as E. coli. Minimum inhibitory concentrations (MIC of fluoroquinolones of these 30 E. coli isolates were evaluated by resazurin microtiter assay. Then, the quinolone resistance determining region (QRDR (gyrA and parC genes of these E. coli isolates was genetically analyzed for determining the chromosomal mutation causing fluoroquinolone resistance. Results: E. coli isolates showed a resistance rate of 63.33%, 23.33% and 30.03% to nalidixic acid, ciprofloxacin and enrofloxacin, respectively. Mutations were found at 83rd and 87th amino acid position of gyrA gene, and at 80th and 108th amino acid position of parC gene in our study isolates. Among these five isolates, one had a single mutation at 83 amino acid position of gyrA with reduced susceptibility (0.5 μg/ml to ciprofloxacin. Then, in remaining four isolates, three isolates showed triple mutation (at gyrA: S83gL and D87gN; at parC: S80gI and the fifth isolate showed an additional mutation at codon 108 of parC (A108gT with the increased ciprofloxacin MIC of 16-128 μg/ml. The most common mutation noticed were at S83gL and D87gN of gyrA and S80gI of ParC. Conclusion: The study confirms the presence of mutation/s responsible for fluoroquinolone resistance in QRDR of gyrA and parC genes of E. coli isolates of animal origin, and there is increased rate of fluoroquinolone resistance with high-level of MIC. The mutations observed in this study were similar to that of human isolates.

  20. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014).

    Science.gov (United States)

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-12-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin in veal calves and chickens, for ciprofloxacin and nalidixic acid in chickens, for sulfamethoxazole in veal calves, chickens and pigs and for tetracycline in veal calves. Using logistic regression and Generalized Estimating Equation and after p value adjustment for multiple testing (Linear step-up method), statistically significant decreasing temporal trends were observed for several of the 11 tested antimicrobials in several livestock categories: in veal calves (10/11), in chickens (6/11) and in pigs (5/11). A significant increasing trend was observed for the prevalence of resistance to ciprofloxacin in chickens. Multi-resistance, considered as the resistance to at least three antimicrobials of different antibiotic classes, was observed in the four livestock categories but was significantly decreasing in veal calves, chickens and pigs. Overall, the prevalence of resistance and of multi-resistance was lowest in the beef cattle livestock category and highest in broiler chickens. These decreasing temporal trends of antimicrobial resistance might be due to a decrease of the total antimicrobial consumption for veterinary use in Belgium which was reported for the period between 2010 and 2013. The methodology and statistical tools developed in this study provide outputs which can detect shifts in resistance levels or resistance trends associated with particular antimicrobial classes and livestock categories. Such outputs can be used as objective evidence to evaluate the possible

  1. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014).

    Science.gov (United States)

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-12-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin in veal calves and chickens, for ciprofloxacin and nalidixic acid in chickens, for sulfamethoxazole in veal calves, chickens and pigs and for tetracycline in veal calves. Using logistic regression and Generalized Estimating Equation and after p value adjustment for multiple testing (Linear step-up method), statistically significant decreasing temporal trends were observed for several of the 11 tested antimicrobials in several livestock categories: in veal calves (10/11), in chickens (6/11) and in pigs (5/11). A significant increasing trend was observed for the prevalence of resistance to ciprofloxacin in chickens. Multi-resistance, considered as the resistance to at least three antimicrobials of different antibiotic classes, was observed in the four livestock categories but was significantly decreasing in veal calves, chickens and pigs. Overall, the prevalence of resistance and of multi-resistance was lowest in the beef cattle livestock category and highest in broiler chickens. These decreasing temporal trends of antimicrobial resistance might be due to a decrease of the total antimicrobial consumption for veterinary use in Belgium which was reported for the period between 2010 and 2013. The methodology and statistical tools developed in this study provide outputs which can detect shifts in resistance levels or resistance trends associated with particular antimicrobial classes and livestock categories. Such outputs can be used as objective evidence to evaluate the possible

  2. Multidrug resistant Escherichia coli strains isolated from urine sample, University of Gondar Hospital, Northwest Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Setegn Eshetie; Fentahun Tarekegn; Gemechu Kumera; Feleke Mekonnen

    2016-01-01

    Objective: To assess multidrug resistant (MDR) Escherichia coli (E. coli) isolates from patients with urinary tract infection. Methods: From February to June 2014, a cross sectional study was conducted among urinary tract infection patients at the University of Gondar Hospital. Culture and disk diffusion method were used for E. coli isolation and to determine the antibiotic susceptibility patterns. Data were entered and analyzed using SPSS version 20. P Results: A total of 112 E. coli isolates were identified and the rate of isolation was higher among female participants (28.7%; P = 0.03). Of the isolates, 104 (92.9%) were MDR E. coli; and the isolates showed high resistance rates towards ampicillin (99%), cotrimoxazole (69%), chloramphenicol (58.7%), gentamycin (56.7%) and ceftazidime (55.8%). However, comparative isolates showed low resistance rates to ciprofloxacin (1%), cefepime (8.7%), and ceftriaxone (11.5%). Moreover, resistance rates of MDR E. coli isolates were significantly higher than non-MDR strains for ceftazidime (55.8% versus 12.5%; P = 0.015), and ampicillin (99% versus 87.5%; P = 0.018). Conclusions: High prevalence of MDR E. coli isolates was observed in this study. Regular monitoring of antibiotic resistance rates is necessarily required to improve and revise empirical antibiotic therapy protocols.

  3. Are ciprofloxacin dosage regimens adequate for antimicrobial efficacy and prevention of resistance? Pseudomonas aeruginosa bloodstream infection in elderly patients as a simulation case study.

    Science.gov (United States)

    Cazaubon, Yoann; Bourguignon, Laurent; Goutelle, Sylvain; Martin, Olivier; Maire, Pascal; Ducher, Michel

    2015-12-01

    The aim of this work was to define the optimal dosage (OD) of ciprofloxacin in order to prevent the emergence of bacterial resistance of Pseudomonas aeruginosa in a geriatric population with a bloodstream infection. A thousand pharmacokinetic profiles were simulated with a ciprofloxacin pharmacokinetic model from the literature. Three dosing regimens were tested for five days: once daily (QD), twice daily (BID), and thrice daily (TID). First of all, effective dosages (ED) of ciprofloxacin were defined as those achieving a target AUC24 /MIC ≥ 125. Then, these ED were simulated in order to calculate the percentage of time spent within the mutant selection window (TMSW ) and to select optimal dosage (OD) defined as those achieving TMSW ≤ 20%. Based on the AUC24 /MIC, for low MICs (0.125 μg/mL), all dosing regimens recommended by French guidelines were effective. For intermediate MICs (0.25 and 0.5 μg/mL), simulated doses higher than those recommended were needed to achieve the efficacy target. About prevention of resistance for low MICs, dosages recommended were only effective in patients with creatinine clearance (CLCR ) ≥ 60 mL/min. For intermediate MICs, dosages higher than recommended were needed to achieve the optimality target. This study shows that current ciprofloxacin dosing guidelines have not been optimized to prevent the emergence of bacterial resistance, especially in geriatric patients with mild to severe renal impairment. To achieve both efficacy and prevention of resistance, ciprofloxacin dosages greater than those recommended would be needed. Tolerance of such higher doses needs to be evaluated in clinical studies.

  4. Septic arthritis of the hip in a Cambodian child caused by multidrug-resistant Salmonella enterica serovar Typhi with intermediate susceptibility to ciprofloxacin treated with ceftriaxone and azithromycin.

    Science.gov (United States)

    Pocock, J M; Khun, P A; Moore, C E; Vuthy, S; Stoesser, N; Parry, C M

    2014-08-01

    Septic arthritis is a rare complication of typhoid fever. A 12-year-old boy without pre-existing disease attended a paediatric hospital in Cambodia with fever and left hip pain. A hip synovial fluid aspirate grew multidrug-resistant Salmonella enterica ser. Typhi with intermediate susceptibility to ciprofloxacin. Arthrotomy, 2 weeks of intravenous ceftriaxone and 4 weeks of oral azithromycin led to resolution of symptoms. The optimum management of septic arthritis in drug-resistant typhoid is undefined.

  5. Susceptibilities of penicillin-susceptible and -resistant strains of Streptococcus pneumoniae to RP 59500, vancomycin, erythromycin, PD 131628, sparfloxacin, temafloxacin, win 57273, ofloxacin, and ciprofloxacin.

    OpenAIRE

    Spangler, S K; Jacobs, M R; Appelbaum, P C

    1992-01-01

    The MICs of four new quinolones, sparfloxacin (AT-4140, CI-978), PD 131628 (the active form of the prodrug CI-990), temafloxacin, and Win 57273, compared with those of ciprofloxacin and ofloxacin were tested against 53 penicillin-susceptible, 35 penicillin intermediate-resistant, and 51 penicillin-resistant pneumococci. Susceptibility to RP 59500, a new streptogramin, was also tested and compared with those to the quinolones, erythromycin, and vancomycin. All MICs were determined by a standar...

  6. Efficacy of ciprofloxacin in experimental aortic valve endocarditis caused by a multiply beta-lactam-resistant variant of Pseudomonas aeruginosa stably derepressed for beta-lactamase production.

    OpenAIRE

    Bayer, A S; Lindsay, P.; Yih, J; Hirano, L; Lee, D.; Blomquist, I K

    1986-01-01

    The emergence of multi-beta-lactam resistance is a limiting factor in treating invasive Pseudomonas infections with newer cephalosporins. The in vivo efficacy of ciprofloxacin, a new carboxy-quinolone, was evaluated in experimental aortic valve endocarditis caused by a strain of Pseudomonas aeruginosa which is stably derepressed for beta-lactamase production and is resistant to ceftazidime and multiple other beta-lactam agents. A total of 51 catheterized rabbits with aortic catheters in place...

  7. Determination Pattern of Antibiotic Resistance in Entropathogenic Escherichia coli Strains Isolated from Children with Diarrhea

    Directory of Open Access Journals (Sweden)

    P. Karami

    2012-04-01

    Full Text Available Introduction & Objective: Diarrheal diseases are considered a major health problem, especially in children. Enteropathogenic Escherichia coli (EPEC strains are the common cause of diarrhea in children especially in developing countries. Because of undesirable effects of diarrhea and its interference with children's growth, in some cases antibiotic treatment is recommended. In recent years, resistance toward common and effective antibiotics in the treatment of infectious diseases became one of the most important challenges in medical society, for this purpose, antibiotic sensitivity and resistance of strains in every geographical zone must be determined. So in this study, of antibiotic patterns of these bacteria were examined.Materials & Methods: This cross-sectional study was performed on 192 strains of Enteropathogen Escherichia coli isolated from children who were suffering from diarrhea in 1389-1390 in the microbiology laboratory of Hamadan University of medical sciences. To identify these strains, standard biochemical and serology tests were used. The antibiotic sensitivity test of these isolates was carried out with disc diffusion agar method according to the CLSI standards for 14 different antibiotics disc. Resistance toward 3 or more than 3 classes of antibiotics were defined as multidrug resistance.Results: The result of this study shows EPEC strains had the highest resistance to cefpodoxime (97%, trimethoprim (60.7%, tetracycline (58.4% and ampicillin (45.8%. Multidrug resistance was 68.7 percent. These strains also showed the highest sensitivity against imipenem, ceftriaxone, and ciprofloxacin antibiotics.Conclusion: EPEC strains that were studied with resistance to ampicillin, tetracycline and convenient sensitivity against fluoroquinolones are one of the major factors in children’s diarrhea. A result of this research suggests that antimicrobial resistance in Escherichia coli strains are high and prescribing and antibiotic is not

  8. Identification of Genome-Wide Mutations in Ciprofloxacin-Resistant F. tularensis LVS Using Whole Genome Tiling Arrays and Next Generation Sequencing

    Science.gov (United States)

    Jaing, Crystal J.; McLoughlin, Kevin S.; Thissen, James B.; Zemla, Adam; Vergez, Lisa M.; Bourguet, Feliza; Mabery, Shalini; Fofanov, Viacheslav Y.; Koshinsky, Heather; Jackson, Paul J.

    2016-01-01

    Francisella tularensis is classified as a Class A bioterrorism agent by the U.S. government due to its high virulence and the ease with which it can be spread as an aerosol. It is a facultative intracellular pathogen and the causative agent of tularemia. Ciprofloxacin (Cipro) is a broad spectrum antibiotic effective against Gram-positive and Gram-negative bacteria. Increased Cipro resistance in pathogenic microbes is of serious concern when considering options for medical treatment of bacterial infections. Identification of genes and loci that are associated with Ciprofloxacin resistance will help advance the understanding of resistance mechanisms and may, in the future, provide better treatment options for patients. It may also provide information for development of assays that can rapidly identify Cipro-resistant isolates of this pathogen. In this study, we selected a large number of F. tularensis live vaccine strain (LVS) isolates that survived in progressively higher Ciprofloxacin concentrations, screened the isolates using a whole genome F. tularensis LVS tiling microarray and Illumina sequencing, and identified both known and novel mutations associated with resistance. Genes containing mutations encode DNA gyrase subunit A, a hypothetical protein, an asparagine synthase, a sugar transamine/perosamine synthetase and others. Structural modeling performed on these proteins provides insights into the potential function of these proteins and how they might contribute to Cipro resistance mechanisms. PMID:27668749

  9. Comparative therapeutic activities of Ciprofloxacin, Amoxicillin, Ceftriaxone and Cotrimoxazole in a new model of experimental infection with Escherichia coli

    OpenAIRE

    Hof, H.; Christen, A; Hacker, Jörg

    2009-01-01

    A new mouse model for systemic infection with Escherichia coli is presented. Whereas in other models 107_108 bacteria have to be injected into an animal to induce toxic effects resulting in death within 24 hours, now, only 103_104 bacteria of an appropriate strain are required to produce a genuine infection characterized by an increase in the bacterial load over several days. The quantitative determination of bacterial counts per liver allows a more sensitive measurement than recording death ...

  10. armA and aminoglycoside resistance in Escherichia coli.

    Science.gov (United States)

    González-Zorn, Bruno; Teshager, Tirushet; Casas, María; Porrero, María C; Moreno, Miguel A; Courvalin, Patrice; Domínguez, Lucas

    2005-06-01

    We report armA in an Escherichia coli pig isolate from Spain. The resistance gene was borne by self-transferable IncN plasmid pMUR050. Molecular analysis of the plasmid and of the armA locus confirmed the spread of this resistance determinant.

  11. Epidemiology of Staphylococcus aureus in Bangalore, India: emergence of the ST217 clone and high rate of resistance to erythromycin and ciprofloxacin in the community

    Science.gov (United States)

    Bouchiat, C.; El-Zeenni, N.; Chakrakodi, B.; Nagaraj, S.; Arakere, G.; Etienne, J.

    2015-01-01

    This study aimed to determine the antibiotic susceptibility pattern of Staphylococcus aureus (SA) and the circulating clones in Bangalore, India. Susceptibility testing was performed for all cases of SA infections in a tertiary-care hospital. Panton-Valentine leucocidin (PVL) encoding genes were detected, and sequence type and spa type were determined. Out of the 92 collected strains, 52.2% were methicillin-resistant SA (MRSA), isolated from community-acquired (CA) infections in 60.4% and hospital-acquired (HA) infections in 39.6%. S. aureus isolates were also highly resistant to erythromycin (54.3%) and ciprofloxacin (70.6%) in methicillin-susceptible SA (MSSA) and MRSA, as well as in CA and HA infections. MRSA were found to be significantly more resistant to gentamicin (p <0.001), cotrimoxazole (p <0.001) and ciprofloxacin (p 0.001) than MSSA, but no significant difference was observed between CA- and HA-SA. ST217 appeared as a new emerging and prevalent clone, but ST772 remained the predominant clone, all being PVL-positive isolates. Our study points out the high prevalence of MRSA, even in the community, and the worrying increase of resistance to ciprofloxacin and erythromycin among CA-MSSA. Emergence of clone ST217 is reported for the first time in India. PMID:26110062

  12. Analysis of the membrane proteome of ciprofloxacin-resistant macrophages by stable isotope labeling with amino acids in cell culture (SILAC.

    Directory of Open Access Journals (Sweden)

    Nancy E Caceres

    Full Text Available Overexpression of multidrug transporters is a well-established mechanism of resistance to chemotherapy, but other changes may be co-selected upon exposure to drugs that contribute to resistance. Using a model of J774 macrophages made resistant to the fluoroquinolone antibiotic ciprofloxacin and comparing it with the wild-type parent cell line, we performed a quantitative proteomic analysis using the stable isotope labeling with amino acids in cell culture technology coupled with liquid chromatography electrospray ionization Fourier transform tandem mass spectrometry (LC-ESI-FT-MS/MS on 2 samples enriched in membrane proteins (fractions F1 and F2 collected from discontinuous sucrose gradient. Nine hundred proteins were identified with at least 3 unique peptides in these 2 pooled fractions among which 61 (F1 and 69 (F2 showed a significantly modified abundance among the 2 cell lines. The multidrug resistance associated protein Abcc4, known as the ciprofloxacin efflux transporter in these cells, was the most upregulated, together with Dnajc3, a protein encoded by a gene located downstream of Abcc4. The other modulated proteins are involved in transport functions, cell adhesion and cytoskeleton organization, immune response, signal transduction, and metabolism. This indicates that the antibiotic ciprofloxacin is able to trigger a pleiotropic adaptative response in macrophages that includes the overexpression of its efflux transporter.

  13. Genetic determinants of heat resistance in Escherichia coli

    OpenAIRE

    Ryan eMercer; Jinshui eZheng; Rigoberto eGarcia-Hernandez; Lifang eRuan; Michael eGänzle; Lynn eMcMullen

    2015-01-01

    Escherichia coli AW1.7 is a heat resistant food isolate and the occurrence of pathogenic strains with comparable heat resistance may pose a risk to food safety. To identify the genetic determinants of heat resistance, 29 strains of E. coli that differed in their of heat resistance were analyzed by comparative genomics. Strains were classified as highly heat resistant strains, exhibiting a D60-value of more than 6 min; moderately heat resistant strains, exhibiting a D60-value of more than 1 mi...

  14. Antimicrobial Resistant Pattern of Escherichia Coli Strains Isolated from Pediatric Patients in Jordan

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    Mohammad Alshara

    2011-05-01

    Full Text Available The present study was conducted to investigate antimicrobial resistant pattern of Escherichia coli (E. coli strains isolated from clinical specimens of Jordanian pediatric patients during the period from January to December 2008. A total of 444 E. coli strains were isolated from clinical specimens and tested for their susceptibility to different antimicrobial drugs. Overall, high resistance rate was observed for ampicillin (84%, followed by amoxicillin-clavulanic acid (74.3%, cotrimoxazole (71%, nalidixic acid (47.3%, cephalothin (41%. Lower resistance rates were observed for amikacin (0% followed by Cefotaxime (11%, Ceftriaxone (11.7%, ciprofloxacin (14.5%, Norfloxacin (16.5%, gentamicin (17.3% cephalexin (20.9%, Ceftazidime (22.5%, cefixime (29.6%, and cefaclor (32.8%. Ampicillin, amoxicillin-clavulanic acid and cotrimoxazole were found to be ineffective at in vitro inhibition of the E. coli of pediatric origin. Amikacin was highly effective for E. coli with susceptibility rate of 100%. The majority of E. coli strains were susceptible to third generation cephalosporins and fluoroquinolones.

  15. MOLECULAR-PHYLOGENETIC CHARACTERIZATION AND ANTIMICROBIAL RESISTANCE OF Escherichia coli ISOLATED FROM GOATS WITH DIARRHEA

    Directory of Open Access Journals (Sweden)

    Rodrigo Almeida Guimarães

    2015-10-01

    Full Text Available Neonatal diarrhea determines significant changes in feed conversion, causing productivity loss in caprine herds. The antimicrobial resistance in bacteria is characterized as an important public health issue; therefore, Escherichia coli may be characterized as an important pathogen due to expressing virulence mechanisms responsible for significant clinical conditions in humans and animals. The present study evaluated the presence of E. coli among 117 caprine fecal samples and analyzed the isolates for antimicrobial resistance. Suggestive colonies were submitted to biochemical screening followed by genotypic group determination and phylogenetic analysis; further, the samples were submitted to antimicrobials susceptibility test. E. coli, Salmonella spp, Shigella sonnei and Enterobacter aerogenes were identified. E. coli isolates were phylogenetically classified as B2 (9/39, D (19/39, B1 (7/39 e A (4/29 groups. The analysis of the isolates also revealed the presence of K99 (04/39 and Stx (02/39 virulence factors. Antimicrobial susceptibility test revealed sensitive isolates to Chloramphenicol, Streptomycin, Amoxicillin and Ciprofloxacin, being all resistant to Lincomycin, Vancomycin and Penicillin. The results support the need of establishing restricted protocols for antimicrobial use, a fundamental procedure for health improvement in Brazilian caprine herds.

  16. Widespread antibiotic resistance of diarrheagenic Escherichia coli and Shigella species

    OpenAIRE

    Azam Fatahi Sadeghabadi; Ali Ajami; Reza Fadaei; Masoud Zandieh; Elham Heidari; Mahmoud Sadeghi; Behrooz Ataei; Shervin Ghaffari Hoseini

    2014-01-01

    Background: Antibiotic resistance of enteric pathogens particularly Shigella species, is a critical world-wide problem and monitoring their resistant pattern is essential, because the choice of antibiotics is absolutely dependent on regional antibiotic susceptibility patterns. During summer 2013, an unusual increase in number of diarrheal diseases was noticed in Isfahan, a central province of Iran. Therefore, the antibiotic resistance of diarrheagenic Escherichia coli and Shigella species iso...

  17. Comparative Activities of Clinafloxacin, Grepafloxacin, Levofloxacin, Moxifloxacin, Ofloxacin, Sparfloxacin, and Trovafloxacin and Nonquinolones Linozelid, Quinupristin-Dalfopristin, Gentamicin, and Vancomycin against Clinical Isolates of Ciprofloxacin-Resistant and -Susceptible Staphylococcus aureus Strains

    OpenAIRE

    Jones, Mark E.; Visser, Maarten R.; Klootwijk, Miriam; Heisig, Peter; Verhoef, Jan; Schmitz, Franz-Josef

    1999-01-01

    The activities of eight fluoroquinolones and linezolid, quinupristin-dalfopristin (Synercid), gentamicin, and vancomycin were tested against 96 ciprofloxacin-susceptible and 205 ciprofloxacin-resistant Staphylococcus aureus strains. Overall, clinafloxacin, followed by moxifloxacin and trovafloxacin, was the most active quinolone tested. For all isolates, linezolid and quinupristin-dalfopristin showed activities that were at least comparable to vancomycin, with no cross-resistance to any other...

  18. Prevalence of multi-drug resistant uropathogenic Escherichia coli in Potohar region of Pakistan

    Institute of Scientific and Technical Information of China (English)

    Ihsan Ali; Zara Rafaque; Safia Ahmed; Sajid Malik; Javid Iqbal Dasti

    2016-01-01

    Objective: To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli (UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections. Methods: Bacterial samples (n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad. Antibiotic susceptibility profiling and determination of mini-mum inhibitory concentrations (MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute (CLSI, 2012). Genes, qnrA, qnrB and qnrS were identified by DNA amplification and sequencing. Results: The highest percentage of UPEC isolates were resistant to co-trimoxazole (82%) followed by cephalothin (80%), 2nd Gen, 3rd Gen and 4th Gen cephalosporins, respectively. Resistance against gentamicin, amikacin remained 29% and 4%. For other drugs including nitrofurantoin, tetracycline, carbapenem and beta-lactam inhibitors remained below 10%. Altogether, 59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone. Overall, MICs for ciprofloxacin remained (MIC≥256 mg/mL) and for levofloxacin (MIC≥16 mg/mL and 32 mg/mL). No significant differences were observed regarding MIC values of extended spectrum b-lactamase (ESBL) and non-ESBL producers. For qnrS and qnrB positive isolates MICs remained above 32 mg/mL. Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers. Conclusions: Higher percentages of ESBL producing UPEC were associated with uri-nary tract infections. Moreover, the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.

  19. Mechanobiology of Antimicrobial Resistant Escherichia coli and Listeria innocua.

    Science.gov (United States)

    Tajkarimi, Mehrdad; Harrison, Scott H; Hung, Albert M; Graves, Joseph L

    2016-01-01

    A majority of antibiotic-resistant bacterial infections in the United States are associated with biofilms. Nanoscale biophysical measures are increasingly revealing that adhesive and viscoelastic properties of bacteria play essential roles across multiple stages of biofilm development. Atomic Force Microscopy (AFM) applied to strains with variation in antimicrobial resistance enables new opportunities for investigating the function of adhesive forces (stickiness) in biofilm formation. AFM force spectroscopy analysis of a field strain of Listeria innocua and the strain Escherichia coli K-12 MG1655 revealed differing adhesive forces between antimicrobial resistant and nonresistant strains. Significant increases in stickiness were found at the nanonewton level for strains of Listeria innocua and Escherichia coli in association with benzalkonium chloride and silver nanoparticle resistance respectively. This advancement in the usage of AFM provides for a fast and reliable avenue for analyzing antimicrobial resistant cells and the molecular dynamics of biofilm formation as a protective mechanism.

  20. Contributions of efflux pumps to high level resistance of Pseudomonas aeruginosa to ciprofloxacin

    Institute of Scientific and Technical Information of China (English)

    WANG Dan-dan; SUN Tie-ying; HU Yun-jian

    2007-01-01

    @@ Pseudomonas aeruginosa (P. aeruginosa) is one of the leading pathogens involved in nosocomial pneumonia. In addition, P. aeruginosa infection is associated with significant morbidity and mortality.1 A major problem in P. aeruginosa infection is that this organism exhibits natural and acquired resistance to many structurally and functionally diverse antibiotics.

  1. Enterobacterial detection and Escherichia coli antimicrobial resistance in parrots seized from the illegal wildlife trade.

    Science.gov (United States)

    Hidasi, Hilari Wanderley; Hidasi Neto, José; Moraes, Dunya Mara Cardoso; Linhares, Guido Fontgallad Coelho; Jayme, Valéria de Sá; Andrade, Maria Auxiliadora

    2013-03-01

    Enteric bacteria are considered important potential pathogens in avian clinical medicine, causing either primary or opportunistic infections. The aim of this study was to evaluate the frequency of enterobacteria in the intestinal microbiota of psittacine birds and to determine the antimicrobial susceptibility of the Escherichia coli isolates cultured. Fecal samples were collected from 300 parrots captured from the illegal wildlife trade in Goiás, Brazil and were processed using conventional bacteriological procedures. A total of 508 isolates were obtained from 300 fecal samples: 172 E. coli (33.9% of isolates; 57.3% of individuals); 153 Enterobacter spp. (30.1% of isolates; 51.0% of individuals); 89 Klebsiella spp. (17.7% of isolates; 29.7% of individuals); 59 Citrobacter spp. (11.6% of isolates; 19.7% of individuals), 21 Proteus vulgaris (4.2% of isolates; 7.0% of individuals), 5 Providencia alcalifaciens (0.98% of isolates; 1.67% of individuals), 5 Serratia sp. (0.98% of isolates; 1.67% of individuals), 3 Hafnia aivei (0.59% of isolates; 1.00% of individuals), and 1 Salmonella sp. (0.20% of isolates; 0.33% of individuals). Escherichia coli isolates were subsequently tested for susceptibility to the following antibiotics: amoxicillin (70.93% of the isolates were resistant), ampicillin (75.58%), ciprofloxacin (23.25%), chloramphenicol (33.14%), doxycycline (64.53%), enrofloxacin (41.28%), tetracycline (69.19%), and sulfonamide (71.51%). Multi-resistance to three and four groups of antibiotics occurred in 40 samples (23.25%) and 4 samples (2.32%), respectively. These results demonstrate that illegally traded birds are carriers of potentially pathogenic bacteria, including E. coli strains with antimicrobial resistance.

  2. Antimicrobial resistance of Escherichia coli isolated in newly-hatched chickens and effect of amoxicillin treatment during their growth.

    Science.gov (United States)

    Jiménez-Belenguer, Ana; Doménech, Eva; Villagrá, Arantxa; Fenollar, Alejandro; Ferrús, Maria Antonia

    2016-08-01

    The use of antimicrobials in food animals is the major determinant for the propagation of resistant bacteria in the animal reservoir. However, other factors may also play a part, and in particular vertical spread between the generations has been suggested to be an important transmission pathway. The objective of this paper was to determine the resistance patterns of Escherichia coli isolated from newly-hatched chickens as well as to study the antibiotic pressure effect when amoxicillin was administered during their growing period. With this aim, meconium from 22 one-day-old Ross chickens was analysed. In addition, during their growth period, amoxicillin treatments at days 7, 21 and 35 were carried out. Results showed a high number of E. coli-resistant strains were isolated from the treated one-day-old chickens, and were the highest for β-lactams group, followed by quinolone and tetracyclines. After treatment with amoxicillin, the highest percentage of resistances were detected for this antibiotic compared to the others analysed, with significant differences in resistance percentages between control and treated broilers detected in relation to ampicillin, cephalothin, streptomycin, kanamycin, gentamicin, chloramphenicol and tetracycline. Differences in resistances to ciprofloxacin and nalidixic acid between control and treated animals were not observed and there was lack of resistance for amikacin and ceftriaxone. These results suggest the possibility of vertical transmission of resistant strains to newly-hatched chicks from parent flocks, and seem to indicate that the treatment with amoxicillin increased the resistance of E. coli to other antibiotics. PMID:27035748

  3. Fluoroquinolone-resistance mechanisms and phylogenetic background of clinical Escherichia coli strains isolated in south-east Poland.

    Science.gov (United States)

    Korona-Glowniak, Izabela; Skrzypek, Kinga; Siwiec, Radosław; Wrobel, Andrzej; Malm, Anna

    2016-09-01

    Fluorochinolones are a class of broad-spectrum antimicrobials in the treatment of several infections, including those caused by Escherichia coli. Due to the increasing resistance of bacteria to antimicrobials, an understanding of fluoroquinolone resistance is important for infection control. The aim of this study was to determine susceptibility of clinical E. coli strains to fluoroquinolones and characterize their mechanisms of quinolone resistance. Totally, 79 non-duplicate clinical E. coli isolates included in this study were mainly from skin lesion -36 (45.6%) isolates; 54 (68.4%) isolates were assigned to phylogenetic B2 group. Resistance to ciprofloxacin was found in 20 isolates. In the quinolone resistance-determining region (QRDR) region of gyrA and parC, 4 types of point mutations were detected. Mutations in parC gene were found in all strains with gyrA mutations. Predominance of double mutation in codon 83 and 87 of gyrA (90%) and in codon 80 of parC (90%) was found. Moreover, plasmid-mediated quinolone resistance (PMRQ) determinants (qnrA or qnrB and/or aac(6')-Ib-cr) were present in 5 (25%) out of 20 fluoroquinolone-resistant isolates. Resistance to fluoroquinolones in all of the tested clinical E. coli isolates correlated with point mutations in both gyrA and parC. The majority of fluoroquinolone-resistant strains belonged to D and B2 phylogenetic groups. PMID:27602420

  4. Molecular characterization of quinolone resistance mechanisms and extended-spectrum β-lactamase production in Escherichia coli isolated from dogs.

    Science.gov (United States)

    Meireles, D; Leite-Martins, L; Bessa, L J; Cunha, S; Fernandes, R; de Matos, A; Manaia, C M; Martins da Costa, P

    2015-08-01

    The increasing prevalence of antimicrobial resistances is now a worldwide problem. Investigating the mechanisms by which pets harboring resistant strains may receive and/or transfer resistance determinants is essential to better understanding how owners and pets can interact safely. Here, we characterized the genetic determinants conferring resistance to β-lactams and quinolones in 38 multidrug-resistant Escherichia coli isolated from fecal samples of dogs, through PCR and sequencing. The most frequent genotype included the β-lactamase groups TEM (n=5), and both TEM+CTX-M-1 (n=5). Within the CTX-M group, we identified the genes CTX-M-32, CTX-M-1, CTX-M-15, CTX-M-55/79, CTX-M-14 and CTX-M-2/44. Thirty isolates resistant to ciprofloxacin presented two mutations in the gyrA gene and one or two mutations in the parC gene. A mutation in gyrA (reported here for the first time), due to a transversion and transition (TCG→GTG) originating a substitution of a serine by a valine in position 83 was also detected. The plasmid-encoded quinolone resistance gene, qnrs1, was detected in three isolates. Dogs can be a reservoir of genetic determinants conferring antimicrobial resistance and thus may play an important role in the spread of antimicrobial resistance to humans and other co-habitant animals.

  5. Molecular characterization of quinolone resistance mechanisms and extended-spectrum β-lactamase production in Escherichia coli isolated from dogs.

    Science.gov (United States)

    Meireles, D; Leite-Martins, L; Bessa, L J; Cunha, S; Fernandes, R; de Matos, A; Manaia, C M; Martins da Costa, P

    2015-08-01

    The increasing prevalence of antimicrobial resistances is now a worldwide problem. Investigating the mechanisms by which pets harboring resistant strains may receive and/or transfer resistance determinants is essential to better understanding how owners and pets can interact safely. Here, we characterized the genetic determinants conferring resistance to β-lactams and quinolones in 38 multidrug-resistant Escherichia coli isolated from fecal samples of dogs, through PCR and sequencing. The most frequent genotype included the β-lactamase groups TEM (n=5), and both TEM+CTX-M-1 (n=5). Within the CTX-M group, we identified the genes CTX-M-32, CTX-M-1, CTX-M-15, CTX-M-55/79, CTX-M-14 and CTX-M-2/44. Thirty isolates resistant to ciprofloxacin presented two mutations in the gyrA gene and one or two mutations in the parC gene. A mutation in gyrA (reported here for the first time), due to a transversion and transition (TCG→GTG) originating a substitution of a serine by a valine in position 83 was also detected. The plasmid-encoded quinolone resistance gene, qnrs1, was detected in three isolates. Dogs can be a reservoir of genetic determinants conferring antimicrobial resistance and thus may play an important role in the spread of antimicrobial resistance to humans and other co-habitant animals. PMID:25999092

  6. Emergence and Diversity of Salmonella enterica Serovar Indiana Isolates with Concurrent Resistance to Ciprofloxacin and Cefotaxime from Patients and Food-Producing Animals in China.

    Science.gov (United States)

    Bai, Li; Zhao, Jiayong; Gan, Xin; Wang, Juan; Zhang, Xiuli; Cui, Shenghui; Xia, Shengli; Hu, Yujie; Yan, Shaofei; Wang, Jiahui; Li, Fengqin; Fanning, Séamus; Xu, Jin

    2016-06-01

    Salmonellosis is a major global foodborne infection, and strains that are resistant to a great variety of antibiotics have become a major public health concern. The aim of this study was to identify genes conferring resistance to fluoroquinolones and extended-spectrum β-lactams in nontyphoidal Salmonella (NTS) from patients and food-producing animals in China. In total, 133 and 21 NTS isolates from animals and humans, respectively, exhibiting concurrent resistance to ciprofloxacin and cefotaxime were cultured independently from 2009 to ∼2013. All of the isolates were identified, serotyped, and subjected to antimicrobial susceptibility testing. Importantly, the isolates with concurrent resistance to ciprofloxacin and cefotaxime all were confirmed as S. enterica serovar Indiana. The presence of fluoroquinolone resistance genes and extended-spectrum β-lactamases (ESBLs) was established by PCR and DNA sequencing. The occurrence and diversity of different genes conferring fluoroquinolone resistance [qepA, oqxAB, and aac(6')-Ib-cr] with mutations in topoisomerase-encoding genes (gyrA and parC) and several ESBLs (including CTX-M-65, CTX-M-27, CTX-M-15, CTX-M-14, and CTX-M-14/CTX-M-15) were noteworthy. Genes located on mobile genetic elements were identified by conjugation and transformation. Pulsed-field gel electrophoresis, used to determine the genetic relationships between these isolates, generated 91 pulsotypes from 133 chicken isolates and 17 pulsotypes from the 21 clinical isolates that showed considerable diversity. Analysis of the pulsotypes obtained with the isolates showed some clones appeared to have existed for several years and had been disseminating between humans and food-producing animals. This study highlights the emergence of ciprofloxacin- and cefotaxime-resistant S. enterica serovar Indiana, posing a threat to public health. PMID:27001808

  7. Ciprofloxacin and Pregnancy

    Science.gov (United States)

    Ciprofloxacin In every pregnancy, a woman starts out with a 3-5% chance of having a baby ... advice from your health care provider. What is ciprofloxacin? Ciprofloxacin is an antibiotic used to treat a ...

  8. Persistence mechanisms in Pseudomonas aeruginosa from cystic fibrosis patients undergoing ciprofloxacin therapy.

    OpenAIRE

    Diver, J M; Schollaardt, T; Rabin, H R; Thorson, C; Bryan, L E

    1991-01-01

    The mechanisms of persistence to ciprofloxacin in nine sets of Pseudomonas aeruginosa strains isolated during ciprofloxacin therapy of chronic lung infections in cystic fibrosis patients were studied. Low to moderate levels of ciprofloxacin resistance developed in each case. Each set of pretherapy ciprofloxacin-susceptible, during-therapy ciprofloxacin-resistant, and posttherapy ciprofloxacin-susceptible isolates were shown to be genotypically related by using a radiolabeled epidemiological g...

  9. Ciprofloxacin interactions with imipenem and amikacin against multiresistant Pseudomonas aeruginosa.

    OpenAIRE

    Giamarellou, H; Petrikkos, G

    1987-01-01

    In vitro interactions of ciprofloxacin with imipenem and amikacin were evaluated by the killing-curve technique against 26 Pseudomonas aeruginosa strains resistant to amikacin and resistant or moderately susceptible to ciprofloxacin and imipenem. Imipenem enhanced killing by ciprofloxacin in tests with 11 strains, whereas amikacin enhanced killing in tests with only 4 strains.

  10. Impacts of urbanization on the prevalence of antibiotic-resistant Escherichia coli in the Chaophraya River and its tributaries.

    Science.gov (United States)

    Honda, Ryo; Watanabe, Toru; Sawaittayotin, Variga; Masago, Yoshifumi; Chulasak, Rungnapa; Tanong, Kulchaya; Chaminda, G Tushara; Wongsila, Krison; Sienglum, Chawala; Sunthonwatthanaphong, Varisara; Poonnotok, Anupong; Chiemchaisri, Wilai; Chiemchaisri, Chart; Furumai, Hiroaki; Yamamoto, Kazuo

    2016-01-01

    River water samples were taken from 32 locations around the basin of Chaophraya River and its four major tributaries in Thailand to investigate resistance ratios of Escherichia coli isolates to eight antibiotic agents of amoxicillin, sulfamethoxazole/trimethoprim, tetracycline, doxytetracycline, ciprofloxacin, levofloxacin, norfloxacin and ofloxacin. Principal component analysis was performed to characterize resistance patterns of the samples. Relevancy of the obtained principal components with urban land use and fecal contamination of the river were examined. The ratio of antibiotic-resistant bacteria is likely to increase when urban land use near the sampling site exceeds a certain ratio. The resistance ratio to fluoroquinolones tends to be high in a highly populated area. Meanwhile, no significant contribution of fecal contamination was found to increase the resistance ratio. These results suggest that an antibiotic-resistance ratio is dependent on conditions of local urbanization rather than the upstream conditions, and that the major sources of antibiotic-resistant bacteria in the Chaophraya River basin are possibly point sources located in the urban area which contains a high ratio of resistant bacteria. PMID:26819392

  11. Antimicrobial activity of peptidomimetics against multidrug-resistant Escherichia coli

    DEFF Research Database (Denmark)

    Jahnsen, Rasmus D; Frimodt-Møller, Niels; Franzyk, Henrik

    2012-01-01

    -lactamase-producing Escherichia coli was assessed by testing an array comprising different types of cationic peptidomimetics obtained by a general monomer-based solid-phase synthesis protocol. Most of the peptidomimetics possessed high to moderate activity toward multidrug-resistant E. coli as opposed to the corresponding...

  12. Multidrug-Resistant Escherichia coli in Bovine Animals, Europe.

    Science.gov (United States)

    Brennan, Evan; Martins, Marta; McCusker, Matthew P; Wang, Juan; Alves, Bruno Martins; Hurley, Daniel; El Garch, Farid; Woehrlé, Frédérique; Miossec, Christine; McGrath, Leisha; Srikumar, Shabarinath; Wall, Patrick; Fanning, Séamus

    2016-09-01

    Of 150 Escherichia coli strains we cultured from specimens taken from cattle in Europe, 3 had elevated MICs against colistin. We assessed all 3 strains for the presence of the plasmid-mediated mcr-1 gene and identified 1 isolate as mcr-1-positive and co-resistant to β-lactam, florfenicol, and fluoroquinolone antimicrobial compounds. PMID:27533105

  13. Current perspectivesin pathogenesis and antimicrobial resistance of enteroaggregative Escherichia coli.

    Science.gov (United States)

    Kong, Haishen; Hong, Xiaoping; Li, Xuefen

    2015-08-01

    Enteroaggregative Escherichia coli (EAEC) is an emerging pathogen that causes acute and persistent diarrhea in children and adults. While the pathogenic mechanisms of EAEC intestinal colonization have been uncovered (including bacterial adhesion, enterotoxin and cytotoxin secretion, and stimulation of mucosal inflammation), those of severe extraintestinal infections remain largely unknown. The recent emergence of multidrug resistant EAEC represents an alarming public health threat and clinical challenge, and research on the molecular mechanisms of resistance is urgently needed.

  14. Prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli isolated from animals, foods and humans in Iceland.

    Science.gov (United States)

    Thorsteinsdottir, T R; Haraldsson, G; Fridriksdottir, V; Kristinsson, K G; Gunnarsson, E

    2010-05-01

    The prevalence of resistant bacteria in food products in Iceland is unknown, and little is known of the prevalence in production animals. The aim of this study was to investigate the prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli from healthy pigs and broiler chicken, pork, broiler meat, slaughterhouse personnel and outpatients in Iceland. A total of 419 E. coli isolates were tested for antimicrobial susceptibility using a microbroth dilution method (VetMIC), and resistant strains were compared using pulsed-field gel electrophoresis (PFGE). All samples were screened for enrofloxacin-resistant strains with selective agar plates. The resistance rates among E. coli isolates were moderate to high from caecal and meat samples of pigs (54.1% and 28%), broilers (33.6% and 52%) and slaughterhouse personnel (39.1%), whereas isolates from outpatients showed moderate resistance rates (23.1%). Of notice was resistance to quinolones (minimum inhibitory concentrations: nalidixic acid > or = 32, ciprofloxacin > or = 0.12 and enrofloxacin > or = 0.5), particularly among broiler and broiler meat isolates (18.2% and 36%), as there is no known antimicrobial selection pressure in the broiler production in Iceland. The majority (78.6%) of the resistant E. coli isolates was genotypically different, based on PFGE fingerprint analyses and clustering was limited. However, the same resistance pattern and pulsotype were found among isolates from broiler meat and a slaughterhouse worker, indicating spread of antimicrobial-resistant E. coli from animals to humans. Diverse resistance patterns and pulsotypes suggest the presence of a large population of resistant E. coli in production animals in Iceland. This study gives baseline information on the prevalence of antimicrobial-resistant E. coli from production animals, and their food products in Iceland and the moderate to high resistance rates emphasize the need for continuing surveillance. Further studies on the

  15. Antibiotic resistance and resistance genes in Escherichia coli from poultry farms, southwest Nigeria

    DEFF Research Database (Denmark)

    Adelowo, Olawale O.; Fagade, Obasola E.; Agersø, Yvonne

    2014-01-01

    Introduction: This study investigated the mechanisms of resistance in 36 E. coli isolated from waste, litter, soil and water samples collected from poultry farms in Southwestern Nigeria. Methodology: Minimum inhibitory concentration (MIC) distributions of the isolates were determined using...... the methods of the Clinical and Laboratory Standard Institute and resistance genes detected by PCR. Results: A total of 30 isolates (94%) showed resistance to more than one antimicrobial. Percentage resistance was: tetracycline 81%, sulphamethoxazole 67%, streptomycin 56%, trimethoprim 47 %, ciprofloxacin 42......%, ampicillin 36%, spectinomycin 28%, nalidixic acid 25%, chloramphenicol 22%, neomycin 14%, gentamicin 8%, amoxicillin-clavulanate, ceftiofur, cefotaxime, colistin, florfenicol and apramycin 0%. Resistance genes found among the isolates include bla-TEM (85%), sul2 (67%), sul3 (17%), aadA (65%), strA (70%), str...

  16. Fitness Costs and Stability of a High-Level Ciprofloxacin Resistance Phenotype in Salmonella enterica Serotype Enteritidis: Reduced Infectivity Associated with Decreased Expression of Salmonella Pathogenicity Island 1 Genes

    Science.gov (United States)

    The fitness costs associated with high-level fluoroquinolone resistance were examined in phenotypically and genotypically characterized ciprofloxacin-resistant Salmonella Enteritidis mutants (104-cip and 5408-cip, MIC > 32 µg/ml). The stability of the fluoroquinolone resistance phenotype in both mut...

  17. Ciprofloxacin in neonatal Enterobacter cloacae septicaemia.

    OpenAIRE

    Bannon, M J; Stutchfield, P R; Weindling, A M; Damjanovic, V.

    1989-01-01

    Multiresistant Enterobacter cloacae infection in six premature infants was eradicated with intravenous ciprofloxacin (10 mg/kg/day). Bacterial resistance did not develop. Adequate plasma ciprofloxacin concentrations were achieved in all treated patients. No clinical evidence of side effects was observed.

  18. Multidrug-resistant Escherichia coli soft tissue infection investigated with bacterial whole genome sequencing

    Science.gov (United States)

    Buchanan, Ruaridh; Stoesser, Nicole; Crook, Derrick; Bowler, Ian C J W

    2014-01-01

    A 45-year-old man with dilated cardiomyopathy presented with acute leg pain and erythema suggestive of necrotising fasciitis. Initial surgical exploration revealed no necrosis and treatment for a soft tissue infection was started. Blood and tissue cultures unexpectedly grew a Gram-negative bacillus, subsequently identified by an automated broth microdilution phenotyping system as an extended-spectrum β-lactamase producing Escherichia coli. The patient was treated with a 3-week course of antibiotics (ertapenem followed by ciprofloxacin) and debridement for small areas of necrosis, followed by skin grafting. The presence of E. coli triggered investigation of both host and pathogen. The patient was found to have previously undiagnosed liver disease, a risk factor for E. coli soft tissue infection. Whole genome sequencing of isolates from all specimens confirmed they were clonal, of sequence type ST131 and associated with a likely plasmid-associated AmpC (CMY-2), several other resistance genes and a number of virulence factors. PMID:25331151

  19. Quinolone-resistant Escherichia coli isolated from birds of prey in Portugal are genetically distinct from those isolated from water environments and gulls in Portugal, Spain and Sweden.

    Science.gov (United States)

    Vredenburg, Jana; Varela, Ana Rita; Hasan, Badrul; Bertilsson, Stefan; Olsen, Björn; Narciso-da-Rocha, Carlos; Bonnedahl, Jonas; Stedt, Johan; Da Costa, Paulo Martins; Manaia, Célia M

    2014-04-01

    The influence of geographic distribution and type of habitat on the molecular epidemiology of ciprofloxacin resistant Escherichia coli was investigated. Ciprofloxacin resistant E. coli from wastewater, urban water with faecal contamination and faeces of gulls, pigeons and birds of prey, from Portugal, Spain and Sweden were compared based on multi-locus sequence typing (MLST) and quinolone resistance genetic determinants. Multi-locus sequence typing allowed the differentiation of E. coli lineages associated with birds of prey from those inhabiting gulls and waters. E. coli lineages of clinical relevance, such as the complex ST131, were detected in wastewater, streams and gulls in Portugal, Spain and Sweden. Quinolone resistance was due to gyrA and parC mutations, although distinct mutations were detected in birds of prey and in wastewater, streams and gulls isolates. These differences were correlated with specific MLST lineages, suggesting resistance inheritance. Among the plasmid-mediated quinolone resistance genes, only aac(6')-ib-cr and qnrS were detected in wastewater, streams and gulls isolates, but not in birds of prey. The horizontal transfer of the gene aac(6')-ib-cr could be inferred from its occurrence in different MLST lineages. PMID:24034690

  20. Prevalence of Antibiotic-Resistant Fecal Escherichia coli Isolates from Penned Broiler and Scavenging Local Chickens in Arusha, Tanzania.

    Science.gov (United States)

    Rugumisa, Bernadether T; Call, Douglas R; Mwanyika, Gaspary O; Mrutu, Rehema I; Luanda, Catherine M; Lyimo, Beatus M; Subbiah, Murugan; Buza, Joram J

    2016-08-01

    We compared the prevalence of antibiotic-resistant Escherichia coli isolates from household-level producers of broiler (commercial source breeds) and local chickens in the Arusha District of Tanzania. Households were composed of a single dwelling or residence with independent, penned broiler flocks. Free-range, scavenging chickens were mixed breed and loosely associated with individual households. A total of 1,800 E. coli isolates (1,200 from broiler and 600 from scavenging local chickens) from 75 chickens were tested for their susceptibility against 11 antibiotics by using breakpoint assays. Isolates from broiler chickens harbored a higher prevalence of antibiotic-resistant E. coli relative to scavenging local chickens, including sulfamethoxazole (80.3 versus 34%), followed by trimethoprim (69.3 versus 27.7%), tetracycline (56.8 versus 20%), streptomycin (52.7 versus 24.7%), amoxicillin (49.6 versus 17%), ampicillin (49.1 versus 16.8%), ciprofloxacin (21.9 versus 1.7%), and chloramphenicol (1.5 versus 1.2%). Except for resistance to chloramphenicol, scavenging local chickens harbored fewer resistant E. coli isolates (P < 0.05). Broiler chickens harbored more isolates that were resistant to ≥7 antibiotics (P < 0.05). The higher prevalence of antibiotic-resistant E. coli from broiler chickens correlated with the reported therapeutic and prophylactic use of antibiotics in this poultry population. We suggest that improved biosecurity measures and increased vaccination efforts would reduce reliance on antibiotics by these households.

  1. Insertion sequence disruption of adeR and ciprofloxacin resistance caused by efflux pumps and gyrA and parC mutations in Acinetobacter baumannii.

    Science.gov (United States)

    Lopes, B S; Amyes, S G B

    2013-02-01

    Acinetobacter baumannii is a pathogenic bacterium responsible for a wide range of infections in immunocompromised patients. This study examined the role of insertional inactivation of the adeR gene and its effect on adeABC gene expression along with characterisation of the gyrA and parC mutations involved in ciprofloxacin resistance in three A. baumannii clinical isolates and their derivatives. Primers designed for the detection of adeSRABC detected the presence of ISAba16, which disrupted the adeR gene in strain Ab12M, and ISAba1, which disrupted the same gene in strains Ab18 and Ab209. A second copy of ISAba1 was detected upstream of the adeA gene in Ab209 leading to AdeABC pump expression. AdeIJK pump expression was seen in all of the isolates but was not as significant as AdeABC expression. Minimum inhibitory concentrations of ciprofloxacin were ≥256 mg/L for all of the isolates and a decrease of ≥8-fold was seen following addition of the efflux pump inhibitor 1-(1-naphthylmethyl)-piperazine. Fluorometric analysis also demonstrated active efflux, with upregulation of adeIJK and some genes of the adeABC operon in some strains. Sequencing of the quinolone resistance-determining region of the gyrA and parC genes revealed a Ser83→Leu change in the gyrA gene and a novel change of Ser80→Trp in the parC gene of Ab12, Ab12M and Ab209; in Ab18 there was a Ser80→Leu change in parC. This study shows the multifactorial contribution of different mechanisms in A. baumannii leading to ciprofloxacin resistance. PMID:23217848

  2. Escherichia coli Isolated from Urinary Tract Infections of Lebanese Patients between 2005 and 2012: Epidemiology and Profiles of Resistance

    Directory of Open Access Journals (Sweden)

    Ziad eDaoud

    2015-04-01

    Full Text Available The early treatment of urinary tract infections is directly related to decrease in morbidity, which makes the empirical treatment of great importance. Recently, beta lactamases of several types have emerged as significant mechanisms of resistance in Gram negative bacilli, especially Escherichia coli. Our aim was to study the urinary E.coli isolated from Lebanese patients and to characterize their mechanisms of resistance. The study analyzed data between 2005 and 2012 of urinary tract infections caused by E.coli. The mechanisms of resistance were characterized by phenotypic and genotypic methods and the Pulsed Field Gel Electrophoresis was used to determine the different bacterial clusters. As expected, the highest incidence was observed with E. coli (60.53 to 73.98% followed by K pneumoniae (5.32 to 8.33%. ICU isolates were constantly associated with the lowest rates of susceptibility to extended spectrum cephalosporins, ciprofloxacin, as well as most of the tested antibiotics. A 100% occurrence of CTX-M in ESBL producing isolates was recorded, followed by TEM, SHV, and OXA. In addition, 15.9% harbored 4 different ESBL enzymes and only 13 isolates (14.8% harbored only one enzyme (CTX-M. Over the years, the simultaneous susceptibility of E. coli to ceftazidime and ciprofloxacin decreased from 62.5% in 2006 to 48.7% in 2012. PFGE results demonstrated that 10 clusters were 32 generated, denoting diversity among detected isolates. Understanding the epidemiology of resistance is 33 instrumental for the implementation of recommendations for the management of antimicrobials, infection 34 control measures, as well as active surveillance and antimicrobial stewardship.

  3. Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

    NARCIS (Netherlands)

    Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

    2005-01-01

    The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC

  4. Induction of Fibronectin Adhesins in Quinolone-Resistant Staphylococcus aureus by Subinhibitory Levels of Ciprofloxacin or by Sigma B Transcription Factor Activity Is Mediated by Two Separate Pathways

    Science.gov (United States)

    Li, Dongmei; Renzoni, Adriana; Estoppey, Tristan; Bisognano, Carmelo; Francois, Patrice; Kelley, William L.; Lew, Daniel P.; Schrenzel, Jacques; Vaudaux, Pierre

    2005-01-01

    We recently reported on the involvement of a RecA-LexA-dependent pathway in the ciprofloxacin-triggered upregulation of fibronectin-binding proteins (FnBPs) by fluoroquinolone-resistant Staphylococcus aureus. The potential additional contribution of the transcription factor sigma B (SigB) to the ciprofloxacin-triggered upregulation of FnBPs was studied in isogenic mutants of fluoroquinolone-resistant strain RA1 (a topoisomerase IV gyrase double mutant of S. aureus NCTC strain 8325), which exhibited widely different levels of SigB activity, as assessed by quantitative reverse transcription-PCR of their respective sigB and SigB-dependent asp23 transcript levels. These mutants were Tn551 insertion sigB strain TE1 and rsbU+ complemented strain TE2, which exhibited a wild-type SigB operon. Levels of FnBP surface display and fibronectin-mediated adhesion were lower in sigB mutant TE1 or higher in the rsbU+-restored strain TE2 compared to their sigB+ but rsbU parent, strain RA1, exhibiting low levels of SigB activity. Steady-state fnbA and fnbB transcripts levels were similar in strains TE1 and RA1 but increased by 4- and 12-fold, respectively, in strain TE2 compared to those in strain RA1. In contrast, fibronectin-mediated adhesion of strains TE1, RA1, and TE2 was similarly enhanced by growth in the presence of one-eighth the MIC of ciprofloxacin, which led to a significantly higher increase in their fnbB transcript levels compared to the increase in their fnbA transcript levels. Increased SigB levels led to a significant reduction in agr RNAIII; in contrast, it led to a slight increase in sarA transcript levels. In conclusion, upregulation of FnBPs by increased SigB levels and ciprofloxacin exposure in fluoroquinolone-resistant S. aureus occurs via independent pathways whose concerted actions may significantly promote bacterial adhesion and colonization. PMID:15728884

  5. Molecular basis of valine resistance in Escherichia coli K-12.

    OpenAIRE

    Lawther, R P; Calhoun, D H; Adams, C W; Hauser, C A; Gray, J.; Hatfield, G W

    1981-01-01

    The relationship of valine resistance to the expression of the ilvGEDA operon of Escherichia coli K-12 has been determined. DNA sequence and in vivo protein analyses indicate that in wild-type E. coli K-12 there is a frameshift site within the gene (ilvG) for valine resistance. The ilvG+2096 (formerly designated ilv02096) mutation displaces this frameshift site, resulting in the expression of ilvG and the relief of transcriptional polarity on the distal genes of this operon. Thus, the "ilv0" ...

  6. Plasmid-mediated formaldehyde resistance in Escherichia coli: characterization of resistance gene.

    OpenAIRE

    Kümmerle, N; Feucht, H H; Kaulfers, P M

    1996-01-01

    The formaldehyde resistance mechanisms in the formaldehyde-resistant strain Escherichia coli VU3695 were investigated. A large (4.6-kb) plasmid DNA fragment encompassing the formaldehyde resistance gene was sequenced. A single 1,107-bp open reading frame encoding a glutathione- and NAD-dependent formaldehyde dehydrogenase was identified and sequenced, and the enzyme was expressed in an in vitro assay and purified. Amino acid sequence homology studies showed 62.4 to 63.2% identity with class I...

  7. A response regulator from a soil metagenome enhances resistance to the β-lactam antibiotic carbenicillin in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Heather K Allen

    Full Text Available Functional metagenomic analysis of soil metagenomes is a method for uncovering as-yet unidentified mechanisms for antibiotic resistance. Here we report an unconventional mode by which a response regulator derived from a soil metagenome confers resistance to the β-lactam antibiotic carbenicillin in Escherichia coli. A recombinant clone (βlr16 harboring a 5,169 bp DNA insert was selected from a metagenomic library previously constructed from a remote Alaskan soil. The βlr16 clone conferred specific resistance to carbenicillin, with limited increases in resistance to other tested antibiotics, including other β-lactams (penicillins and cephalosporins, rifampin, ciprofloxacin, erythromycin, chloramphenicol, nalidixic acid, fusidic acid, and gentamicin. Resistance was more pronounced at 24°C than at 37°C. Zone-of-inhibition assays suggested that the mechanism of carbenicillin resistance was not due to antibiotic inactivation. The DNA insert did not encode any genes known to confer antibiotic resistance, but did have two putative open reading frames (ORFs that were annotated as a metallopeptidase and a two-component response regulator. Transposon mutagenesis and subcloning of the two ORFs followed by phenotypic assays showed that the response regulator gene was necessary and sufficient to confer the resistance phenotype. Quantitative reverse transcriptase PCR showed that the response regulator suppressed expression of the ompF porin gene, independently of the small RNA regulator micF, and enhanced expression of the acrD, mdtA, and mdtB efflux pump genes. This work demonstrates that antibiotic resistance can be achieved by the modulation of gene regulation by heterologous DNA. Functional analyses such as these can be important for making discoveries in antibiotic resistance gene biology and ecology.

  8. Antimicrobial susceptibility testing of Escherichia coli strains isolated from urinary tract infections to fluoroquinolones and detection of gyrA mutations in resistant strains

    Directory of Open Access Journals (Sweden)

    Akbari-Nakhjavani F.

    2007-05-01

    Full Text Available Widespread uses of fluoroquinolones have resulted in increasing incidences of resistance against these agents all over the world. The aim of this study was to assess, susceptibility of Escherichia coli strains from patients with Urinary Tract Infection against common fluoroquinolones and detection of mutations in the gyrA gene. Antimicrobial susceptibility testing of 164 E.coli isolates from patients with UTI, was evaluated by disk agar diffusion (DAD and MIC methods. Polymerase chain reaction of E.coli strains were performed by amplification of Quinolone Resistance Determining Region (QRDR of gyrA gene. PCR products were tested by Conformational Sensitive Gel Electrophoresis (CSGE and those with hetrodublexes were selected and examined by DNA sequencing. According to disc agar diffusion, 49.3% were resistant to nalidixic acid, 41.4% to norfloxacin, 44.5% to ofloxacin and 40.2 % to ciprofloxacin. By Minimal Inhibitory Concentration (MIC testing a high-level of resistance (42.1% to ciprofloxacin was observed. Mutations in codons 83 and 87 in all 81 isolates were positive by CSGE method.

  9. Occurrence of multidrug resistance to oral antibiotics among Escherichia coli urine isolates from outpatient departments in Germany: extended-spectrum β-lactamases and the role of fosfomycin.

    Science.gov (United States)

    Kresken, Michael; Pfeifer, Yvonne; Hafner, Dieter; Wresch, Rebecca; Körber-Irrgang, Barbara

    2014-10-01

    The in vitro activities of fosfomycin and seven other antibiotics commonly used for oral treatment of urinary tract infections (UTIs) were evaluated for 499 Escherichia coli isolated from urine samples during a nationwide laboratory-based surveillance study in 2010. Overall, the highest resistance rates were found for amoxicillin (42.9%), followed by amoxicillin/clavulanic acid (32.7%), trimethoprim/sulfamethoxazole (SXT) (30.9%), ciprofloxacin (19.8%), cefuroxime (10.0%), cefpodoxime (8.6%) and cefixime (8.2%). One-half of the isolates (n=252; 50.5%) were fully susceptible to the eight drugs, whilst only 6 strains (1.2%) were resistant to fosfomycin. Combined resistance to amoxicillin, cefuroxime, ciprofloxacin and SXT was detected in 29 isolates (5.8%). Moreover, 40 isolates (8.0%) produced an extended-spectrum β-lactamase (ESBL), including CTX-M-type ESBLs detected in 39/40 isolates (97.5%) and a TEM-52 ESBL in 1 strain (2.5%). The predominant CTX-M-type ESBL was CTX-M-15 (27/39; 69.2%). Of the 27 CTX-M-15 producers, 19 (70.4%) belonged to the clonal lineage E. coli O25b-ST131. All but one ESBL-producing strains were fosfomycin-susceptible. In view of the emergence of multidrug resistance to standard oral antibiotics, these data support that oral fosfomycin (trometamol salt) may represent a valuable option in the treatment of uncomplicated UTIs.

  10. Genetic determinants of heat resistance in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ryan eMercer

    2015-09-01

    Full Text Available Escherichia coli AW1.7 is a heat resistant food isolate and the occurrence of pathogenic strains with comparable heat resistance may pose a risk to food safety. To identify the genetic determinants of heat resistance, 29 strains of E. coli that differed in their of heat resistance were analyzed by comparative genomics. Strains were classified as highly heat resistant strains, exhibiting a D60-value of more than 6 min; moderately heat resistant strains, exhibiting a D60-value of more than 1 min; or as heat sensitive. A ~14 kb genomic island containing 16 predicted open reading frames encoding putative heat shock proteins and proteases was identified only in highly heat resistant strains. The genomic island was termed the locus of heat resistance (LHR. This putative operon is flanked by mobile elements and possesses >99% sequence identity to genomic islands contributing to heat resistance in Cronobacter sakazakii and Klebsiella pneumoniae. An additional 41 LHR sequences with >87% sequence identity were identified in 11 different species of β- and γ-proteobacteria. Cloning of the full length LHR conferred high heat resistance to the heat sensitive E. coli AW1.7ΔpHR1 and DH5α. The presence of the LHR correlates perfectly to heat resistance in several species of Enterobacteriaceae and occurs at a frequency of 2% of all E. coli genomes, including pathogenic strains. This study suggests the LHR has been laterally exchanged among the β- and γ-proteobacteria and is a reliable indicator of high heat resistance in E. coli.

  11. Ciprofloxacin and Dexamethasone Otic

    Science.gov (United States)

    Ciprofloxacin and dexamethasone otic is used to treat outer ear infections in adults and children and acute ( ... middle ear infections in children with ear tubes. Ciprofloxacin is in a class of medications called quinolone ...

  12. Antibiotic resistance patterns of more than 120 000 clinical Escherichia coli isolates in Southeast Austria, 1998-2013.

    Science.gov (United States)

    Badura, A; Feierl, G; Pregartner, G; Krause, R; Grisold, A J

    2015-06-01

    Antibiotic resistance patterns of more than 120 000 clinical Escherichia coli isolates were retrospectively analysed. Isolates originated from both hospitalized patients and outpatients from the region of southeast Austria from 1998 to 2013. Except for amoxicillin/clavulanic acid, nitrofurantoin and piperacillin/tazobactam, all of the antibiotics analysed showed increasing proportions of resistant isolates over time, which were most prominent for ampicillin (from 25.4% in 1998 to 40% in 2013), cefotaxime (0.1% to 6.7%), ceftazidime (0.3% to 14.2%), ciprofloxacin (4.3% to 16.7%) and trimethoprim/sulfamethoxazole (14.6% to 24.8%). There was a marked increase in extended-spectrum β-lactamase-positive isolates (0.1% to 6.3%) starting in 2005, with male patients and hospital-related patients showing a higher increase than female patients and outpatients. Proportions of resistant isolates for most antibiotics were generally higher for male patients and hospital-related patients. Amikacin, nitrofurantoin and trimethoprim/sulfamethoxazole showed a marked increase in resistance proportions among male subjects aged 10 to 19 years which were absent for female subjects, indicating a strong modulation potential of host characteristics.

  13. 环丙沙星体外诱导肺炎克雷伯菌耐药机制的研究%Mechanisms of Ciprofloxacin-Induced Resistance in Klebsiella Pneumoniae in Vitro

    Institute of Scientific and Technical Information of China (English)

    韩菊梅; 叶晓光

    2015-01-01

    ABSTRACT:Objective To investigate the molecular mechanisms of ciprofloxacin-induced resist-ance in Klebsiella pneumonia (KPn)in vitro.Methods The antibiotic resistance of Klebsiella pneumoniae isolated from patients was induced by ciprofloxacin in vitro using multi-step test method.Ten pairs of susceptible clinical isolates and ciprofloxacin-induced resistant strains were randomly selected in this study.The quinolone resistance determining region (QRDR)of gyrA gene was amplified by PCR,and the expression of TolC protein and porin protein were detected by SDS-PAGE.Results All KPn showed drug resistance after ciprofloxacin induction,and highly drug-resistant bacteria accounted for 73.81%.Among the 10 ciprofloxacin-induced resistant strains,the mutation rate of Ser83 was 30%.In addition,porin expression decreased but TolC ex-pression increased after ciprofloxacin induction.Conclusion The use of ciprofloxacin is closely related to drug resistance and causes the production of a variety of drug-resistant molecules in KPn.%目的:探讨环丙沙星体外诱导敏感肺炎克雷伯菌(KPn)耐药的分子机制。方法对临床分离的敏感肺炎克雷伯菌体外使用环丙沙星,采用多步法诱导耐药,并随机选择10对临床分离敏感菌和诱导后高度耐药菌进行GyrA 基因 QRDR(喹诺酮抗性区,quinolone resistant-determining region)的聚合酶链式反应(PCR)扩增、SDS-PAGE 电泳鉴定外膜外排泵蛋白 TolC 及膜孔蛋白 porin 蛋白的表达。结果诱导后的 KPn 均成为耐药菌,其中高度耐药菌占73.81%。10株诱导的耐药菌中 Ser83突变率为30%;膜孔蛋白 porin 表达均减少,外排泵蛋白 TolC表达均增多。结论环丙沙星的使用与 KPn 耐药密切相关,并可引起 KPn 多种耐药分子产生。

  14. Azorean wild rabbits as reservoirs of antimicrobial resistant Escherichia coli.

    Science.gov (United States)

    Marinho, Catarina; Igrejas, Gilberto; Gonçalves, Alexandre; Silva, Nuno; Santos, Tiago; Monteiro, Ricardo; Gonçalves, David; Rodrigues, Tiago; Poeta, Patrícia

    2014-12-01

    Antibiotic resistance in bacteria is an increasing problem that is not only constrained to the clinical setting but also to other environments that can lodge antibiotic resistant bacteria and therefore they may serve as reservoirs of genetic determinants of antibiotic resistance. One hundred and thirty-six faecal samples from European wild rabbits (Oryctolagus cuniculus algirus) were collected on São Jorge Island in Azores Archipelago, and analysed for Escherichia coli isolates. Seventy-seven isolates (56.6%) were recovered and studied for antimicrobial resistance, one isolate per positive sample. Thirteen (16.9%), 19 (24.7%), 25 (32.4%) and 20 (26%) isolates were ascribed to A, B1, B2 and D phylogenetic groups, respectively, by specific primer polymerase chain reaction. Different E. coli isolates were found to be resistant to ampicillin (16.9%), tetracycline (1.3%), streptomycin (42.9%), sulfamethoxazole-trimethoprim (1.3%), amikacin (1.3%), tobramycin (2.6%) and nalidixic acid (1.3%). Additionally, the blaTEM, tetA, strA/strB, aadA, sul1, intI, intI2 and qacEΔ+sul1 genes were found in most resistant isolates. This study showed that E. coli from the intestinal tract of wild rabbits from Azores Archipelago are resistant to widely prescribed antibiotics in medicine and they constitute a reservoir of antimicrobial resistant genes, which may play a significant role in the spread of antimicrobial resistance. Therefore, antibiotic resistant E. coli from Azorean wild rabbits may represent an ecological and public health problem.

  15. QUINOLONE- AND ETA-LACTAM- RESISTANCE IN Escherichia coli FROM DANISH AND ITALIAN BROILER FLOCKS

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    M. Trevisani

    2009-03-01

    Full Text Available The prevalence of quinolone- and -lactam-resistant E. coli was investigated among healthy broiler flocks in Denmark and Italy. In Denmark, sock samples were collected from 10 parent flocks and 10 offspring flocks, according to the procedure currently used for the surveillance of Salmonella in the EU. Samples were enriched in McConkey broth and streaked on McConkey agar plates added with nalidixic acid (32 g/ml, ciprofloxacin (2 g/ml, ampicillin (32 g/ml, cefotaxime (2 g/ml or ceftiofur (8 g/ml. The -glucuronidase test was performed for verification of presumptive E. coli. The same methods were used to analyse sock samples collected from 6 Italian broiler flocks. PCR with primers for the CTX-M-type extended-spectrum -lactamases (ESBLs was performed on cephalosporin-resistant isolates. While resistance to ampicillin and nalidixic acid was widespread in both countries, resistance to ciprofloxacin and cephalosporins was more common among Italian flocks. In Denmark, ciprofloxacin resistance was only detected in 1 parent flock without any history of quinolone usage and none of the flocks was positive for cephalosporin-resistant E. coli. In Italy, resistance to ciprofloxacin was detected in all flocks and resistance to ceftiofur and cefotaxime were detected in 5 flocks. Primers specific for the CTX-M-type ESBLs generated PCR amplicons from isolates from 3 of these flocks. In industrialized countries, the poultry production system is highly standardized, and therefore comparable. However, the use of broad-spectrum antimicrobials is particularly limited in Danish poultry production. Accordingly, the results of this study could reflect the different policies in antimicrobial usage between the two countries.

  16. Antimicrobial Resistance of Escherichia coli, Enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus from Raw Fish and Seafood Imported into Switzerland.

    Science.gov (United States)

    Boss, Renate; Overesch, Gudrun; Baumgartner, Andreas

    2016-07-01

    A total of 44 samples of salmon, pangasius (shark catfish), shrimps, and oysters were tested for the presence of Escherichia coli, enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus, which are indicator organisms commonly used in programs to monitor antibiotic resistance. The isolated bacterial strains, confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, were tested against a panel of 29 antimicrobial agents to obtain MICs. Across the four sample types, Enterococcus faecalis (59%) was most common, followed by E. coli (55%), P. aeruginosa (27%), and S. aureus (9%). All bacterial species were resistant to some antibiotics. The highest rates of resistance were in E. faecalis to tetracycline (16%), in E. coli to ciprofloxacin (22%), and in S. aureus to penicillin (56%). Antibiotic resistance was found among all sample types, but salmon and oysters were less burdened than were shrimps and pangasius. Multidrug-resistant (MDR) strains were exclusively found in shrimps and pangasius: 17% of pangasius samples (MDR E. coli and S. aureus) and 64% of shrimps (MDR E. coli, E. faecalis, and S. aureus). Two of these MDR E. coli isolates from shrimps (one from an organic sample) were resistant to seven antimicrobial agents. Based on these findings, E. coli in pangasius, shrimps, and oysters, E. faecalis in pangasius, shrimps, and salmon, and P. aeruginosa in pangasius and shrimps are potential candidates for programs monitoring antimicrobial resistance. Enrichment methods for the detection of MDR bacteria of special public health concern, such as methicillin-resistant S. aureus and E. coli producing extended-spectrum β-lactamases and carbapenemases, should be implemented.

  17. Multidrug-Resistant and Extended Spectrum Beta-Lactamase-Producing Escherichia coli in Dutch Surface Water and Wastewater.

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    Hetty Blaak

    Full Text Available The goal of the current study was to gain insight into the prevalence and concentrations of antimicrobial resistant (AMR Escherichia coli in Dutch surface water, and to explore the role of wastewater as AMR contamination source.The prevalence of AMR E. coli was determined in 113 surface water samples obtained from 30 different water bodies, and in 33 wastewater samples obtained at five health care institutions (HCIs, seven municipal wastewater treatment plants (mWWTPs, and an airport WWTP. Overall, 846 surface water and 313 wastewater E. coli isolates were analysed with respect to susceptibility to eight antimicrobials (representing seven different classes: ampicillin, cefotaxime, tetracycline, ciprofloxacin, streptomycin, sulfamethoxazole, trimethoprim, and chloramphenicol.Among surface water isolates, 26% were resistant to at least one class of antimicrobials, and 11% were multidrug-resistant (MDR. In wastewater, the proportions of AMR/MDR E. coli were 76%/62% at HCIs, 69%/19% at the airport WWTP, and 37%/27% and 31%/20% in mWWTP influents and effluents, respectively. Median concentrations of MDR E. coli were 2.2×10(2, 4.0×10(4, 1.8×10(7, and 4.1×10(7 cfu/l in surface water, WWTP effluents, WWTP influents and HCI wastewater, respectively. The different resistance types occurred with similar frequencies among E. coli from surface water and E. coli from municipal wastewater. By contrast, among E. coli from HCI wastewater, resistance to cefotaxime and resistance to ciprofloxacin were significantly overrepresented compared to E. coli from municipal wastewater and surface water. Most cefotaxime-resistant E. coliisolates produced ESBL. In two of the mWWTP, ESBL-producing variants were detected that were identical with respect to phylogenetic group, sequence type, AMR-profile, and ESBL-genotype to variants from HCI wastewater discharged onto the same sewer and sampled on the same day (A1/ST23/CTX-M-1, B23/ST131/CTX-M-15, D2/ST405/CTX-M-15.In

  18. Widespread antibiotic resistance of diarrheagenic Escherichia coli and Shigella species

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    Azam Fatahi Sadeghabadi

    2014-01-01

    Full Text Available Background: Antibiotic resistance of enteric pathogens particularly Shigella species, is a critical world-wide problem and monitoring their resistant pattern is essential, because the choice of antibiotics is absolutely dependent on regional antibiotic susceptibility patterns. During summer 2013, an unusual increase in number of diarrheal diseases was noticed in Isfahan, a central province of Iran. Therefore, the antibiotic resistance of diarrheagenic Escherichia coli and Shigella species isolated were evaluated. Materials and Methods: According to the guideline on National Surveillance System for Foodborn Diseases, random samples from patients with acute diarrhea were examined in local laboratories of health centers and samples suspicious of Shigella spp. were further assessed in referral laboratory. Isolated pathogens were identified by standard biochemical and serologic tests and antibiotic susceptibility testing was carried out by disc diffusion method. Results: A total of 1086 specimens were obtained and 58 samples suspicious of Shigella were specifically evaluated. The most prevalent isolated pathogen was Shigella sonnei (26/58 followed by E. coli (25/58 and Shigella flexneri (3/58. A large number of isolated bacteria were resistant to co-trimoxazole (Shigella spp: 100%, E. coli: 80%, azithromycin (Shigella spp: 70.4%, E. coli: 44.0%, ceftriaxone (Shigella spp: 88.9%, E. coli: 56.0% and cefixime (Shigella spp: 85.2%, E. coli: 68.0%. About88.3% of S. sonnei isolates, one S. flexneri isolate, and 56% of E. coli strains were resistant to at least three antibiotic classes (multidrug resistant. Conclusion: Due to high levels of resistance to recommended and commonly used antibiotics for diarrhea, continuous monitoring of antibiotic resistance seems essential for determining best options of empirical therapy.

  19. Resistencia de Neisseria gonorrhoeae a ciprofloxacina según hábitos sexuales Ciprofloxacin resistance of Neisseria gonorrhoeae according to sexual habits

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    Susana García

    2008-10-01

    heterosexual men. The gonorrhea prevalence in MSM and heterosexual men was 0.091(91/1000 and the Neisseria gonorrhoeae ciprofloxacin resistant (CRNG was 20% in MSM and 3.8% in heterosexual men (p: 0.0416. Thirteen out of 106 isolates from 11 MSM and 2 heterosexual men were CRNG. Six out of eleven MSM had urethritis, one also carried Neisseria gonorrhoeae in rectum and 5 patients were asymptomatic carriers (rectum 2, pharynx 2, urethra 1. No epidemiological relation was found among the patients. Two heterosexual men had urethritis. The 8 symptomatic men were treated with ciprofloxacin but treatment failed in all of them. These patients and the asymptomatic ones were treated with ceftriaxone, 500 mg IM. The post treatment microbiological controls were negative. The CRNG isolates had ciprofloxacin MIC between 2 and 32 (µg/ml, all were negative to penicillinase, 4 out of 13 were chromosomally resistant to penicillin (MIC: 1 µg/ml. The MICs (µg/ml ranges for several antimicrobial agents were: penicillin: 0.016-1; tetracycline: 0.125-2; ceftriaxone: 0.004-0.008; erythromycin: 0.032-2; azithromycin: 0.032-0.5; spectinomycin: 8-32. Due to the high level of ciprofloxacin-resistant N. gonorrhoeae isolated from MSM in our hospital, another antimicrobial agent for empirical therapy should be used in these patients.

  20. Molecular epidemiological survey on quinolone resistance genotype and phenotype of Escherichia coli in septicemic broilers in Hebei, China.

    Science.gov (United States)

    Xie, Rong; Huo, Shuying; Li, Yurong; Chen, Ligong; Zhang, Feiyan; Wu, Xianjun

    2014-02-01

    In this study, the quinolone-resistant determining region (QRDR) of gyrA of Escherichia coli and plasmid-mediated quinolone resistance (PMQR) genes, qnr(qnrA, qnrB, and qnrS), and aac(6 ')-Ib-cr were detected, sequenced, and analyzed. In addition, antimicrobial susceptibility tests (using the Kirby-Bauer disc diffusion method) were performed for all 111 E. coli isolates from septicemic broilers in Hebei, China. The results show that the resistance rates were as follows: ofloxacin 99.10%, ciprofloxacin 93.69%, levofloxacin 91.89%, norfloxacin 90.09%, and gatifloxacin 76.58%. Of the PMQR genes examined, aac(6 ')-Ib-cr (36.04%) was the most frequently identified gene in all isolates, followed by qnrS (8.11%), qnrB (0.90%), and qnrA (0%). Of the QRDR examined in the 40 phenotypic quinolone-resistant isolates, compared with the gyrA(+) gene of E. coli K-12, 4 amino acid exchanges were found, namely Ser-83→Asp, Asp-87→Asn, Asp-87→Tyr, and Asp-87→Ala, and all 40 isolates had 1 or 2 exchanges in QRDR. It was concluded that quinolone-resistance in E. coli remains a serious problem in Hebei, China. Therefore, there is considerable local surveillance of quinolone resistance. Plasmid-mediated quinolone resistance of the qnr type remains rare in Hebei, China, and mutation in QRDR may be the main problem.

  1. Outer membrane alterations in multiresistant mutants of Pseudomonas aeruginosa selected by ciprofloxacin.

    OpenAIRE

    Legakis, N. J.; Tzouvelekis, L. S.; Makris, A; Kotsifaki, H

    1989-01-01

    Spontaneous mutants of Pseudomonas aeruginosa selected by ciprofloxacin were studied for outer membrane alterations. Acquisition of ciprofloxacin resistance was at least partially related to defects in lipopolysaccharide synthesis. When ciprofloxacin resistance was combined with resistance to beta-lactams and aminoglycosides, several alterations in outer membrane proteins were noted.

  2. Heterologously expressed bacterial and human multidrug resistance proteins confer cadmium resistance to Escherichia coli

    OpenAIRE

    Achard-Joris, M; van Saparoea, HBV; Driessen, AJM; Bourdineaud, JP; Bourdineaud, Jean-Paul

    2005-01-01

    The human MDR1 gene is induced by cadmium exposure although no resistance to this metal is observed in human cells overexpressing hMDR1. To access the role of MDR proteins in cadmium resistance, human MDR1, Lactococcus lactis lmrA, and Oenococcus oeni omrA were expressed in an Escherichia coli tolC mutant strain which proved to be hypersensitive to cadmium. Both the human and bacterial MDR genes conferred cadmium resistance to E. coli up to 0.4 mM concentration. Protection was abolished by 10...

  3. Molecular characterization and antibiotic resistance of enterotoxigenic and entero-aggregative Escherichia coli isolated from raw milk and unpasteurized cheeses

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    Mojtaba Bonyadian

    2014-04-01

    Full Text Available The aim of this study was to determine the occurrence of enterotoxigenic and enteroaggregative Escherichia coli strains and antibiotic resistance of the isolates in raw milk and unpasteurized cheese. Out of 200 samples of raw milk and 50 samples of unpasteurized cheeses, 96 and 24 strains of E. coli were isolated, respectively. Polymerase chain reaction (PCR was used to detect the genes encoding heat-stable enterotoxin a (STa, heat-stable enterotoxin b (STb, heat labile toxin (LT and enteroaggregative heat-stable toxin1 (EAST1. Twelve out of 120 (10.00% isolates harbored the gene for EAST1, 2(1.66% isolates were detected as producing STb and LT toxins and 12 (10.00% strains contained STb and EAST1 genes. None of the strains contain the STa gene. All of the strains were tested for antibiotic resistance by disk diffusion method. Disks included: ciprofloxacin (CFN, trimetoprim-sulfamethoxazole (TSX, oxytetracycline (OTC, gentamicin (GMN, cephalexin (CPN, nalidixic acid (NDA and nitrofurantoin (NFN, ampicillin (AMP, neomycin (NEO and streptomycin (STM. Among 120 isolated strains of E. coli, the resistance to each antibiotics were as follows: OTC100%, CPN 86.00%, NDA 56.00%, NFN 42.00%, GMN 30.00%, TSX 28.00%, CFN 20%, AM 23.40% and STM 4.25%. None of the isolates were resistant to NEO. The present data indicate that different resistant E. coli pathogens may be found in raw milk and unpasteurized cheese. It poses an infection risk for human and transferring the resistant factors to microflora of the consumers gut.

  4. Prevalence and characterization of quinolone resistance mechanisms in commensal Escherichia coli isolated from slaughter animals in Poland, 2009-2012.

    Science.gov (United States)

    Wasyl, Dariusz

    2014-12-01

    The background of quinolone resistance was characterized in ciprofloxacin-resistant commensal Escherichia coli selected out of 3,551 isolates from slaughtered animals in Poland between 2009 and 2012. Plasmid-mediated determinants were suspected in 6.2% of the study group, ranging from 1.1% in cattle to 9.7% in turkeys. Polymerase chain reaction and sequencing identified up to four quinolone resistance-determining substitutions in gyrA (Ser83, Asp87) and parC (Ala56, Ser80). Plasmid-mediated mechanisms were identified as qnrS1 (or qnrS3, n=70, including six isolates with chromosomal mutations), qnrB19 (or qnrB10, n=19), and qnrB17 (n=1). All tested isolates were negative for qnrA, qnrC, qnrD, qepA, and aac(6')-Ib-cr. Still, there were several E. coli suspected for both plasmid- and chromosome-mediated resistance with unrevealed genetic background of the phenomenon. Since all tested isolates showed diverse XbaI-PFGE profiles, chromosome-encoded quinolone resistance does not result from the spread of a single resistant clone, however, it is rather due to antimicrobial pressure leading to the selection of random gyr and par mutants. It also favors the selection and spread of plasmids carrying predominant qnr genes, since the same determinants were found in Salmonella, isolated from similar sources. The identification of carrier plasmids and mitigation of their spread might be essential for sustainable quinolone usage in animal husbandry and efficient protection of human health. PMID:25051094

  5. Rapid Evolution of Silver Nanoparticle Resistance in Escherichia coli

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    Joseph L. Graves

    2015-02-01

    Full Text Available The recent exponential increase in the use of engineered nanoparticles (eNPs means both greater intentional and unintentional exposure of eNPs to microbes. Intentional use includes the use of eNPs as biocides. Unintentional exposure results from the fact that eNPs are included in a variety of commercial products (paints, sunscreens, cosmetics. Many of these eNPs are composed of heavy metals or metal oxides such as silver, gold, zinc, titanium dioxide, and zinc oxide. It is thought that since metallic/metallic oxide NPs impact so many aspects of bacterial physiology that it will difficult for bacteria to evolve resistance to them. This study utilized laboratory experimental evolution to evolve silver nanoparticle (AgNP resistance in the bacterium Escherichia coli (K12 MG1655, a bacterium that did not harbor any silver resistance elements. After 225 generations of exposure to the AgNP environment, the treatment populations demonstrated greater fitness versus control strains as measured by optical density (OD and colony forming units (CFU in the presence of varying concentrations of 10nm citrate-coated silver nanoparticles (AgNP or silver nitrate (AgNO3. Genomic analysis shows that changes associated with AgNP resistance were already accumulating within the treatment populations by generation 100, and by generation 200 three mutations had swept to high frequency in the AgNP resistance stocks. This study indicates that despite previous claims to the contrary bacteria can easily evolve resistance to AgNPs, and this occurs by relatively simple genomic changes. These results indicate that care should be taken with regards to the use of eNPs as biocides as well as with regards to unintentional exposure of microbial communities to eNPs in waste products.

  6. Rapid evolution of silver nanoparticle resistance in Escherichia coli.

    Science.gov (United States)

    Graves, Joseph L; Tajkarimi, Mehrdad; Cunningham, Quincy; Campbell, Adero; Nonga, Herve; Harrison, Scott H; Barrick, Jeffrey E

    2015-01-01

    The recent exponential increase in the use of engineered nanoparticles (eNPs) means both greater intentional and unintentional exposure of eNPs to microbes. Intentional use includes the use of eNPs as biocides. Unintentional exposure results from the fact that eNPs are included in a variety of commercial products (paints, sunscreens, cosmetics). Many of these eNPs are composed of heavy metals or metal oxides such as silver, gold, zinc, titanium dioxide, and zinc oxide. It is thought that since metallic/metallic oxide NPs impact so many aspects of bacterial physiology that it will difficult for bacteria to evolve resistance to them. This study utilized laboratory experimental evolution to evolve silver nanoparticle (AgNP) resistance in the bacterium Escherichia coli (K-12 MG1655), a bacterium that does not harbor any known silver resistance elements. After 225 generations of exposure to the AgNP environment, the treatment populations demonstrated greater fitness vs. control strains as measured by optical density (OD) and colony forming units (CFU) in the presence of varying concentrations of 10 nm citrate-coated silver nanoparticles (AgNP) or silver nitrate (AgNO3). Genomic analysis shows that changes associated with AgNP resistance were already accumulating within the treatment populations by generation 100, and by generation 200 three mutations had swept to high frequency in the AgNP resistance stocks. This study indicates that despite previous claims to the contrary bacteria can easily evolve resistance to AgNPs, and this occurs by relatively simple genomic changes. These results indicate that care should be taken with regards to the use of eNPs as biocides as well as with regards to unintentional exposure of microbial communities to eNPs in waste products. PMID:25741363

  7. The occurrence of antimicrobial resistance and class 1 integrons among commensal Escherichia coli isolates from infants and elderly persons

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    Kõljalg Siiri

    2009-12-01

    Full Text Available Abstract Background The aim of our study was to compare the presence of the intI1 gene and its associations with the antibiotic resistance of commensal Escherichia coli strains in children with/without previous antibiotic treatments and elderly hospitalized/healthy individuals. Methods One-hundred-and-fifteen intestinal E. coli strains were analyzed: 30 strains from 10 antibiotic-naive infants; 27 from 9 antibiotic-treated outpatient infants; 30 from 9 healthy elderly volunteers; and 28 from 9 hospitalized elderly patients. The MIC values of ampicillin, cefuroxime, cefotaxime, gentamicin, ciprofloxacin, and sulfamethoxazole were measured by E-test and IntI1 was detected by PCR. Results Out of the 115 strains, 56 (49% carried class 1 integron genes. Comparing persons without medical interventions, we found in antibiotic-naive children a significantly higher frequency of integron-bearing strains and MIC values than in healthy elderly persons (53% versus 17%; p Conclusion The prevalence of integrons in commensal E. coli strains in persons without previous medical intervention depended on age. The resistance of integron-carrying and non-carrying strains is more dependent on influencing factors (hospitalization and antibiotic administration in particular groups than merely the presence or absence of integrons.

  8. 我院大肠埃希菌耐药性分析%Analysis of Antimicrobial Resistance of 266 Escherichia Coli

    Institute of Scientific and Technical Information of China (English)

    任晓华; 崔文丽; 张英; 安翠平; 霍卫池; 汤慧芳; 彭雯; 马涛; 何士彦

    2012-01-01

    Objective To investigate the distribution and situation of antimicrobial resistance of escherichia coli isolated from our hospital in 2011, sa as to provide reference for antimicrobial treatment. Methods A total of 266 strains of escherichia coli isolated during Jan. 2011 and Dec. 2011 were retrospectively analyzed according to the source of specimens and drug-resistance. Results The drug resistance to all kinds of antibiotics was strong. The highest resistance rate of escherichia coli was present in cipro-floxacin (83.2%). In gentamicin, cefazolin, cefuroxitne and ceftriaxone, a lower resistance rate of escherichia coli varying from 70% to 80% was confirmed. In levofloxacin, cefotaxime and ampicillin/sulbactam, the resistance rate was between 60% to 70% , and only the resistance rate of Cefoxitin was less than 50%. Conclusion Escherichia coli, isolated from the patients, has shown a high rate of resistance to routine antimicrobial agents, and even has presented multiple antibacterial resistance. So rational use of antimicrobial agents must be emphasized in order to reduce or delay the production of multi-drug resistant strains.%目的 了解我院2011年大肠埃希菌对常用抗菌药物的耐药现状及标本分布,为临床治疗提供依据.方法 对2011年1月~12月临床科室送培标本分离出的266株大肠埃希菌的耐药情况进行回顾性分析.结果 我院分离的266株大肠埃希菌对各类常用抗菌药物均表现为严重耐药,其中环丙沙星的耐药率最高,达83.2%,庆大霉素、头孢唑林钠、头孢呋辛钠和头孢曲松钠耐药率达70%~80%,左氧氟沙星、头孢噻肟钠、氨苄西林/舒巴坦钠的耐药率在60%~70%,仅头孢西丁钠的耐药率低于50%.结论 我院分离的大肠埃希菌耐药严重,且呈多重耐药,故临床必须重视合理使用抗菌药物,以减少或延缓多重耐药菌株的产生.

  9. Prevalence of antimicrobial resistance and integrons in Escherichia Coli from Punjab, Pakistan

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    Idrees Muhammad

    2011-06-01

    Full Text Available Antimicrobial resistance was studied in Escherichia coli strains isolated from urine samples of 457 patients suffering from urinary tract infection. High prevalence of class 1 integrons (43.56%, sulfamethoxazole resistance genes sul1 (45.54% and sul2 (51.48% along with occurrence of quinolone resistance genes was detected in multi drug resistance isolates.

  10. Experimental evolution of silver nanoparticle resistance in Escherichia coli

    Science.gov (United States)

    Tajkarimi, Mehrdad

    The recent exponential increase in the use of engineered nanoparticles (eNPs) means both greater intentional and unintentional exposure of eNPs to microbes. Intentional use includes the use of eNPs as biocides; unintentional exposure results from the fact that eNPs are included in a variety of commercial products (paints, sunscreens, cosmetics.) Many of these eNPs include heavy metals or metal oxides such as titanium dioxide, silver, gold, zinc and zinc oxide. The fact that early studies of the impact of metallic nanoparticles achieved approximately 90% lethality to Ag, Cu eNPs, suggests that genetic variants are already circulating in bacteria that can be co-opted to provide heavy metal eNP resistance. This project has utilized laboratory experimental evolution to evolve eNP resistance in the bacterium Escherichia coli (K12 MG1655 strain.). This is currently being validated by demonstrating the greater fitness of evolved strains versus ancestral strains in the presence of different sized and coated silver nanoparticles (10nm, 40nm, citrate-coated, PVP-coated) as well as phenotypic changes in the bacterial cell wall (as measured by Atomic Force Microscopy, AFM.). Finally, the bacterial genomes of the evolved and ancestral strains were resequenced. The genomic basis of this complex phenotype was determined. The practical application of such knowledge cannot be underestimated since nature is already evolving nanoparticle resistant bacteria. Thus knowledge of the nature of the physiological, morphological, and genomic mechanisms of resistance will be essential to deploy sustainable use of NPs as biocides, and to prevent unintentional environmental damage.

  11. Occurrence of quinolone- and beta-lactam-resistant Escherichia coli in danish broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne;

    An increased concern for the possible transfer of resistant bacteria or mobile resistance elements from food animals to humans has resulted in rigorous legislation preventing i.e. practical use of fluoroquinolones in the Danish broiler industry (Olesen et al., 2004; Petersen et al., 2006...... and nalidixic acid resistances were detected in all flocks. The numbers of E. coli resistant to these drugs were higher in plates from parent flocks than in those from offspring flocks. A broiler parent flock without any history of quinolone usage tested positive for ciprofloxacin-resistant E. coli, although...... and mutations responsible for these types of resistance. References DANMAP 2005. 2006. Use of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from food animals, foods and humans in Denmark. Danish Veterinary Laboratory, Copenhagen, Denmark, ISSN 1600-2032. Olesen, I., H. Hasman...

  12. Focus on oral ciprofloxacin; clinical and economic considerations.

    Science.gov (United States)

    Pastel, D

    1989-10-01

    Ciprofloxacin, a recently released oral fluorinated quinolone structurally related to nalidixic acid, joins norfloxacin as the second drug of this class to be released. Ciprofloxacin has a wide spectrum of antimicrobial activity and importantly demonstrates little cross resistance to non-quinolone drug classes (e.g. ureidopenicillins, cephalosporins, monobactams, carbapenems, aminoglycosides). Unlike other antibacterial classes such as the beta-lactams or aminoglycosides, ciprofloxacin does not suffer from transferable plasmid-mediated (i.e. R-factor) antibiotic resistance. Against gram-positive (including penicillin-resistant and methicillin-resistant staphylococci aureus) and gram-negative aerobic bacteria including Pseudomonas aeruginosa, ciprofloxacin demonstrates excellent activity. Ciprofloxacin is inactive against Trichomonas sp., treponemes, and fungi and anaerobes are considered resistant. Ciprofloxacin is rapidly absorbed from the gastrointestinal tract (i.e. 70-80% bioavailable), demonstrates extensive extravascular distribution, and its 3.5-5 hour half-life allows twice daily dosing. The bacteriologic and clinical efficacy of oral ciprofloxacin was shown to be comparable to third generation cephalosporins or aminoglycosides for osteomyelitis, cefotaxime for skin structure infections, and to a combination of tobramycin with azlocillin for pulmonary exacerbation of cystic fibrosis. Adverse events associated with ciprofloxacin are related mostly to gastrointestinal disturbance and consist of nausea/vomiting or diarrhea. Concomitant administration of ciprofloxacin and theophylline may lead to decreased theophylline clearance and necessitates periodic measurements of theophylline levels to avoid toxic levels. Treatment with oral ciprofloxacin should offer substantial cost savings over a variety of parenteral antimicrobial regimens (e.g. aminoglycoside + beta-lactams) for difficult to treat infections such as chronic pyelonephritis, osteomyelitis, and skin

  13. Insights into a multidrug resistant Escherichia coli pathogen of the globally disseminated ST131 lineage: genome analysis and virulence mechanisms.

    Directory of Open Access Journals (Sweden)

    Makrina Totsika

    Full Text Available Escherichia coli strains causing urinary tract infection (UTI are increasingly recognized as belonging to specific clones. E. coli clone O25b:H4-ST131 has recently emerged globally as a leading multi-drug resistant pathogen causing urinary tract and bloodstream infections in hospitals and the community. While most molecular studies to date examine the mechanisms conferring multi-drug resistance in E. coli ST131, relatively little is known about their virulence potential. Here we examined E. coli ST131 clinical isolates from two geographically diverse collections, one representing the major pathogenic lineages causing UTI across the United Kingdom and a second representing UTI isolates from patients presenting at two large hospitals in Australia. We determined a draft genome sequence for one representative isolate, E. coli EC958, which produced CTX-M-15 extended-spectrum β-lactamase, CMY-23 type AmpC cephalosporinase and was resistant to ciprofloxacin. Comparative genome analysis indicated that EC958 encodes virulence genes commonly associated with uropathogenic E. coli (UPEC. The genome sequence of EC958 revealed a transposon insertion in the fimB gene encoding the activator of type 1 fimbriae, an important UPEC bladder colonization factor. We identified the same fimB transposon insertion in 59% of the ST131 UK isolates, as well as 71% of ST131 isolates from Australia, suggesting this mutation is common among E. coli ST131 strains. Insertional inactivation of fimB resulted in a phenotype resembling a slower off-to-on switching for type 1 fimbriae. Type 1 fimbriae expression could still be induced in fimB-null isolates; this correlated strongly with adherence to and invasion of human bladder cells and bladder colonisation in a mouse UTI model. We conclude that E. coli ST131 is a geographically widespread, antibiotic resistant clone that has the capacity to produce numerous virulence factors associated with UTI.

  14. The comparative activity of pefloxacin, enoxacin, ciprofloxacin and 13 other antimicrobial agents against enteropathogenic microorganisms.

    Science.gov (United States)

    Vanhoof, R; Hubrechts, J M; Roebben, E; Nyssen, H J; Nulens, E; Leger, J; De Schepper, N

    1986-01-01

    In this study, we compared the activity of pefloxacin, enoxacin and ciprofloxacin against 269 enteropathogenic strains (Campylobacter jejuni, enteropathogenic Escherichia coli, Salmonella typhi, Shigella spp., Vibrio cholerae and Yersinia enterocolitica) with that of rosoxacin, flumequin, nifuroxazide, erythromycin, chloramphenicol, ampicillin, cefotaxime, tetracycline, amikacin, netilmicin, sulfamethoxazole, trimethoprim and co-trimoxazole. Pefloxacin, enoxacin and ciprofloxacin were always among the most active compounds. Furthermore, resistant strains or strains with elevated MIC values were not found. The MIC90 value for these three compounds was less than or equal to 0.25 mg/l, except for C. jejuni where it was 0.3 mg/l and 1.4 mg/l for pefloxacin and enoxacin, respectively. PMID:3546145

  15. Draft Genome Sequence of Neisseria gonorrhoeae Strain NG_869 with Penicillin, Tetracycline and Ciprofloxacin Resistance Determinants Isolated from Malaysia.

    Science.gov (United States)

    Ang, Geik Yong; Yu, Choo Yee; Yong, Delicia Ann; Cheong, Yuet Meng; Yin, Wai-Fong; Chan, Kok-Gan

    2016-06-01

    Gonorrhea is a sexually transmitted infection caused by Neisseria gonorrhoeae and the increasing reports of multidrug-resistant gonococcal isolates are a global public health care concern. Herein, we report the genome sequence of N. gonorrhoeae strain NG_869 isolated from Malaysia which may provide insights into the drug resistance determinants in gonococcal bacteria. PMID:27570316

  16. 泵抑制剂提高肺炎克雷伯菌对环丙沙星的敏感性%Efflux pump Inhibitors improve the sensitivity of ciprofloxacin in drug-resistance Klebsiella pneumoniae

    Institute of Scientific and Technical Information of China (English)

    王若伦; 叶晓光

    2007-01-01

    目的 研究泵抑制剂利血平和羰基氰氯苯腙(CCCP)能否提高肺炎克雷伯菌对环丙沙星的敏感性.方法 收集临床分离对环丙沙星敏感的肺炎克雷伯菌20株,随机抽取10株,应用不同浓度梯度环丙沙星逐级诱导为高耐药株.用琼脂稀释法测定应用泵抑制剂前后,分离的临床敏感株和诱导耐药株的最小抑菌浓度(MIC).结果 应用泵抑制剂利血平和CCCP后,分别有6株(60%)和8株(80%)诱导耐药株的MIC值有所下降,泵阳性株分别有4株和7株.结论 起始低浓度后梯度环丙沙星可以人工诱导出肺炎克雷伯菌高度耐药株.泵抑制剂利血平和CCCP能提高耐药肺炎克雷伯菌对环丙沙星的敏感性.%Objective To explore whether efflux pump inhibitors can improve the sensitivity of ciprofloxacin in drug-resislance Klebsilla pneumoniae. Methods Twenty sensitive strains of Klebsiella pneumoniae were isolated from patients. Ten strains were induced by concentration gradient ciprofloxacin and changed into ciprofloxacin-high resistant Klebsiella pneumoniae. The MICs of ciprofloxacin in the absence or presence of reserpine or carbonyl cyanide m-chlorophenyl hydrazone(CCCP) were detected by agar dilution method. Results After treated with efflux pump inhibitor, the MICs of most induced-resistant bacteria to ciprofloxacin were decreased:6 strains (60%) and 8 strains (80%) in the presence of reserpine and CCCP respectively. The positive efflux pump Klebsiella prveumoniae strains in the presence of reserpine and CCCP were 4(40%) and 6(60%) respectively. Conclusions The high drug-resistance Klebsiella pneumoniae can be artificialy induced with concentration gradient of ciprofloxaein. The efflux pump inhibitors can obviously improve the antibacterial activities of ciprofloxacin in drug-resistance Klebsiella pneumoaiae.

  17. Effect of Attapulgite on The Oral Bioavailability of Ciprofloxacin

    Directory of Open Access Journals (Sweden)

    Zamrotul Izzah

    2013-06-01

    Full Text Available This study was aimed to determine the effect of attapulgite on the bioavailability of a single orallyadministered ciprofloxacin. Six New Zealand white rabbits received each of the following treatments in a randomized, three-way crossover sequence, separated by a 7-day washout period: (i ciprofloxacin (23 mg/kgBW alone; (ii ciprofloxacin (23 mg/kgBW given simultaneously with attapulgite (28 mg/ kgBW; (iii ciprofloxacin (23 mg/kgBW given 2 hours after attapulgite (28 mg/kgBW. Blood samples (1 mL were collected from the marginal ear vein up to 240 minutes postdose. The plasma concentrations of ciprofloxacin were determined by a validated high-performance liquid chromatography method. The maximum concentration and oral bioavailability (AUC0-240 min of ciprofloxacin were significantly decreased by 49 % and 32 % when administered concomitantly with attapulgite (p < 0.001. Attapulgite appeared to have no significant effect on the bioavailability of ciprofloxacin when administered 2 hours before ciprofloxacin. In conclusion, the oral bioavailability of ciprofloxacin was markedly reduced when administered concomitantly with attapulgite. This drug-drug interaction may decrease clinical efficacy and promote microbial resistance to ciprofloxacin. However, the interaction could be minimized by separating the adminsitration of these drugs at least 2 hours.

  18. Clinical efficacy of ciprofloxacin in lower respiratory tract infections.

    Science.gov (United States)

    Pedersen, S S

    1989-01-01

    The sputum pharmacokinetics and clinical efficacy of ciprofloxacin in lower respiratory tract infections is reviewed. Following intravenous administration, ciprofloxacin penetrates rapidly into bronchial tissue; the elimination half life is between 3 and 4 h and a dose dependency is seen. Following oral intake, the time to reach maximal concentrations is approximately two hours and after a dose of 750 mg the concentration may reach 1.7 mg/l in patients without cystic fibrosis and range from 0.5 to 3.4 mg/l in cystic fibrosis patients. Coadministration of ciprofloxacin increases serum levels and decreases total body clearance of theophylline. In controlled comparative clinical trials, ciprofloxacin has been found to have similar clinical efficacy as amoxycillin, ampicillin, cefalexin, doxycycline, co-trimoxazole, imipenem-cilastatin and ceftazidime for the treatment of a range of lower respiratory tract infections. Ciprofloxacin has been found to be superior in clinical efficacy to cefaclor. Experimental animal models suggest a role for ciprofloxacin in infections caused by Legionella pneumophila and Mycoplasma pneumoniae. The clinical and bacteriological efficacy of ciprofloxacin is less pronounced in lung infections caused by Pseudomonas aeruginosa, but is comparable to the combination of beta-lactams and aminoglycosides. Development of resistance is frequently observed during ciprofloxacin treatment of Ps. aeruginosa. Because of the availability of other oral and effective agents, ciprofloxacin is not recommended for empirical treatment of community acquired lower respiratory infections, but should be reserved for infections caused by multiply resistant organisms. PMID:2667111

  19. Differentiation of Mycobacterium chelonei from M. fortuitum by ciprofloxacin susceptibility.

    OpenAIRE

    Collins, C. H.; Yates, M D; Uttley, A H

    1985-01-01

    Seventy-five strains of Mycobacterium fortuitum were inhibited by 3.0 mg/l ciprofloxacin but 36 strains of M. chelonei were resistant. The results correlated well with those obtained by the nitratase test. The ciprofloxacin sensitivity test is a useful supplement to the tests used to identify these two species.

  20. Characterization of Multidrug Resistant Extended-Spectrum Beta-Lactamase-Producing Escherichia coli among Uropathogens of Pediatrics in North of Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Rezai

    2015-01-01

    Full Text Available Escherichia coli remains as one of the most important bacteria causing infections in pediatrics and producing extended-spectrum beta-lactamases (ESBLs making them resistant to beta-lactam antibiotics. In this study we aimed to genotype ESBL-producing E. coli isolates from pediatric patients for ESBL genes and determine their association with antimicrobial resistance. One hundred of the E. coli isolates were initially considered ESBL producing based on their MIC results. These isolates were then tested by polymerase chain reaction (PCR for the presence or absence of CTX, TEM, SHV, GES, and VEB beta-lactamase genes. About 30.5% of isolated E. coli was ESBL-producing strain. The TEM gene was the most prevalent (49% followed by SHV (44%, CTX (28%, VEB (8%, and GES (0% genes. The ESBL-producing E. coli isolates were susceptible to carbapenems (66% and amikacin (58% and showed high resistance to cefixime (99%, colistin (82%, and ciprofloxacin (76%. In conclusion, carbapenems were the most effective antibiotics against ESBl-producing E. coli in urinary tract infection in North of Iran. The most prevalent gene is the TEM-type, but the other resistant genes and their antimicrobial resistance are on the rise.

  1. Kefiran-alginate gel microspheres for oral delivery of ciprofloxacin.

    Science.gov (United States)

    Blandón, Lina M; Islan, German A; Castro, Guillermo R; Noseda, Miguel D; Thomaz-Soccol, Vanete; Soccol, Carlos R

    2016-09-01

    Ciprofloxacin is a broad-spectrum antibiotic associated with gastric and intestinal side effects after extended oral administration. Alginate is a biopolymer commonly employed in gel synthesis by ionotropic gelation, but unstable in the presence of biological metal-chelating compounds and/or under dried conditions. Kefiran is a microbial biopolymer able to form gels with the advantage of displaying antimicrobial activity. In the present study, kefiran-alginate gel microspheres were developed to encapsulate ciprofloxacin for antimicrobial controlled release and enhanced bactericidal effect against common pathogens. Scanning electron microscopy (SEM) analysis of the hybrid gel microspheres showed a spherical structure with a smoother surface compared to alginate gel matrices. In vitro release of ciprofloxacin from kefiran-alginate microspheres was less than 3.0% and 5.0% at pH 1.2 (stomach), and 5.0% and 25.0% at pH 7.4 (intestine) in 3 and 21h, respectively. Fourier transform infrared spectroscopy (FTIR) of ciprofloxacin-kefiran showed the displacement of typical bands of ciprofloxacin and kefiran, suggesting a cooperative interaction by hydrogen bridges between both molecules. Additionally, the thermal analysis of ciprofloxacin-kefiran showed a protective effect of the biopolymer against ciprofloxacin degradation at high temperatures. Finally, antimicrobial assays of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhymurium, and Staphylococcus aureus demonstrated the synergic effect between ciprofloxacin and kefiran against the tested microorganisms. PMID:27289312

  2. Identification of integrons and phylogenetic groups of drug-resistant Escherichia coli from broiler carcasses in China.

    Science.gov (United States)

    Wu, Hao; Xia, Shibo; Bu, Fanyun; Qi, Jing; Liu, Yuqing; Xu, Hai

    2015-10-15

    The dissemination of drug-resistant Escherichia coli in poultry products is becoming a public concern, as it endangers food security and human health. It is very common for E. coli to exhibit drug resistance in the poultry industry in China due to the excessive use of antibiotics. However, few studies have examined the drug resistance endowed by integrons and integron-associated gene cassettes in different phylogenetic groups of E. coli isolated from broiler carcasses. In this study, 373 antibiotic-resistant E. coli strains were isolated from the surfaces or insides of broiler carcasses from a slaughterhouse in Shandong Province, China. According to phylogenetic assays of chuA, yjaA, and an anonymous DNA fragment, TSPE4-C2, these isolates belong to four phylogenetic groups (A, B1, B2, and D) and seven subgroups (A0, A1, B1, B21, B22, D1, and D2). Of the tested isolates, 95.71% (n=357) are multi-drug resistant, among which group B1 was predominant, accounting for 33.51% (n=125) of the tested isolates. A high percentage of the E. coli isolates were resistant to amoxicillin-clavulanic acid (99.20%, n=370), doxycycline (92.23%, n=344), sulfamethoxazole-trimethoprim (90.88%, n=339), ciprofloxacin, (64.61%, n=241), sulbactam-cefoperazone (51.21%, n=191), and amikacin (33.78%, n=126). Furthermore, among the 373 isolates, class 1 and 2 integrons were identified in 292 (78.28%) and 49 (13.14%) of the isolates, respectively, while no class 3 integrons were detected. The most prevalent gene cassette arrays were dfrA17-aadA5 and dfrA12-orfF-aadA2 in the variable region of class 1 integrons, while only one gene cassette array (dfrA1-sat2-aadA1) was detected in the variable region of class 2 integrons. Class 1 integrons were distributed in various physiological subtypes, whereas no predominant phylogenetic groups could be identified. The presence of class 2 integrons in the B21 subtype was significantly higher than in the other subtypes, and it coexisted with the class 1

  3. Influence of montmorillonite on antimicrobial activity of tetracycline and ciprofloxacin

    Science.gov (United States)

    Lv, Guocheng; Pearce, Cody W.; Gleason, Andrea; Liao, Libing; MacWilliams, Maria P.; Li, Zhaohui

    2013-11-01

    Antibiotics are used not only to fight infections and inhibit bacterial growth, but also as growth promotants in farm livestock. Farm runoff and other farm-linked waste have led to increased antibiotic levels present in the environment, the impact of which is not completely understood. Soil, more specifically clays, that the antibiotic contacts may alter its effectiveness against bacteria. In this study a swelling clay mineral montmorillonite was preloaded with antibiotics tetracycline and ciprofloxacin at varying concentrations and bioassays were conducted to examine whether the antibiotics still inhibited bacterial growth in the presence of montmorillonite. Escherichia coli was incubated with montmorillonite or antibiotic-adsorbed montmorillonite, and then the number of viable bacteria per mL was determined. The antimicrobial activity of tetracycline was affected in the presence of montmorillonite, as the growth of non-resistant bacteria was still found even when extremely high TC doses were used. Conversely, in the presence of montmorillonite, ciprofloxacin did inhibit E. coli bacterial growth at high concentrations. These results suggest that the effectiveness of antimicrobial agents in clayey soils depends on the amount of antibiotic substance present, and on the interactions between the antibiotic and the clays in the soil, as well.

  4. Resistencia a antimicrobianos en aislamientos de Escherichia coli de origen animal Antimicrobial resistance of Escherichia coli isolated from animals

    Directory of Open Access Journals (Sweden)

    G. Carloni

    2011-12-01

    Full Text Available Se determinó el perfil de susceptibilidad a antimicrobianos de 100 aislamientos de E.coli provenientes de diversas patologías en bovinos, equinos, caninos y felinos, siguiendo metodología del Clinical and Laboratory Standards Institute y detectando la aparición de aislamientos multiresistentes. El panel de antibióticos ensayados incluyó amicacina, ampicilina/sulbactama, cefotaxima, ciprofloxacina, cloranfenicol, colistina, estreptomicina, gentamicina, nitrofurantoína, tetraciclina, trimetoprima/ sulfametoxazol. El mayor porcentaje de resistencia (R se detectó frente a tetraciclina en aislamientos de todas las especies animales (entre 34% en los de origen felino y 75% de origen equino. En las cepas de origen canino y felino se encontraron porcentajes considerables frente ampicilina/ sulbactama (27% de caninos y 53% de felinos y ante ciprofloxacina (30% y 67% respectivamente. En estos aislamientos también, se detectó el mayor porcentaje de multiresistencia (29% en caninos y 67% en felinos. La presión selectiva originada por la aplicación inadecuada de antibióticos puede resultar un factor, aunque no el único, responsable de la aparición de R. Además existe la posibilidad de que E.coli pueda constituirse en un eslabón de transmisión de genes de R a antimicrobianos, aunque no se conoce hasta el momento, el origen de ellos, humano o animal y, su permanencia en el tiempo.Antimicrobial susceptibility tests were determined in 100 isolates of E.coli from differents patologies in cattle, horses, dogs and cats, according to Clinical and Laboratory Standards Institute. Multiresistance isolates were detected in this assay. The antibiotics selected were amikacin, ampicillin /sulbactam, cefotaxime, ciprofloxacin, chloramphenicol, colistin, gentamicin, nitrofurantoin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole. The antibiotic with the highest resistance was tetracycline (34% in cats and 75% in dogs. In isolated strains from dogs

  5. Effects of Halides on Plasmid-Mediated Silver Resistance in Escherichia coli

    OpenAIRE

    Gupta, Amit; Maynes, Maria; Silver, Simon

    1998-01-01

    Silver resistance of sensitive Escherichia coli J53 and resistance plasmid-containing J53(pMG101) was affected by halides in the growth medium. The effects of halides on Ag+ resistance were measured with AgNO3 and silver sulfadiazine, both on agar and in liquid. Low concentrations of chloride made the differences in MICs between sensitive and resistant strains larger. High concentrations of halides increased the sensitivities of both strains to Ag+.

  6. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

    OpenAIRE

    Nuno Mendonça; Rui Figueiredo; Catarina Mendes; Card, Roderick M.; Anjum, Muna F.; Gabriela Jorge da Silva

    2016-01-01

    The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70%) and ampicillin (63%). Extended-spectrum beta-lactamase (ESBL) phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA m...

  7. Effect of peritoneal dialysis fluid and pH on bactericidal activity of ciprofloxacin.

    OpenAIRE

    McCormick, E M; Echols, R M

    1987-01-01

    Ciprofloxacin is active in vitro against most bacteria that cause peritonitis associated with peritoneal dialysis. We compared the effects of pH (5.5 and 7.4) and medium (dialysis fluid) on the bactericidal activity of ciprofloxacin, tobramycin, vancomycin plus rifampin, and rifampin against Pseudomonas aeruginosa, Escherichia coli, and three strains of staphylococci. The bactericidal activity of ciprofloxacin was not significantly affected by pH or medium, in contrast to the activity of tobr...

  8. Colonization with Extraintestinal Pathogenic Escherichia coli among Nursing Home Residents and Its Relationship to Fluoroquinolone Resistance

    OpenAIRE

    Maslow, Joel N.; Lautenbach, Ebbing; Glaze, Thomas; Bilker, Warren; Johnson, James R.

    2004-01-01

    In a cross-sectional fecal prevalence survey involving 49 residents of a Veterans Affairs nursing home, 59% of subjects were colonized with extraintestinal pathogenic Escherichia coli (ExPEC), 22% were colonized with adhesin-positive E. coli, and 51% were colonized with fluoroquinolone-resistant E. coli. Among 80 unique isolates, adhesins correlated negatively and aerobactin correlated positively with fluoroquinolone resistance.

  9. Molecular characterization of vancomycin-resistant enterococci and extended-spectrum β-lactamase-containing Escherichia coli isolates in wild birds from the Azores Archipelago.

    Science.gov (United States)

    Silva, Nuno; Igrejas, Gilberto; Rodrigues, Pedro; Rodrigues, Tiago; Gonçalves, Alexandre; Felgar, Ana Carolina; Pacheco, Rui; Gonçalves, David; Cunha, Regina; Poeta, Patrícia

    2011-10-01

    To study the prevalence of vancomycin-resistant enterococci (VRE) and extended-spectrum β-lactamase (ESBL)-containing Escherichia coli isolates, and the mechanisms of resistance implicated, 220 faecal samples from wild birds were collected between 2006 and 2010 in the Azores Archipelago. Samples were spread on Slanetz-Bartley agar plates supplemented with 4 mg/l vancomycin and on Levine agar plates supplemented with 2 mg/l cefotaxime for VRE and ESBL-containing E. coli isolation, respectively. vanA-containing enterococcal isolates (four Enterococcus faecium and two Enterococcus durans) and vanC-1 Enterococcus gallinarum isolates were detected in six and seven faecal samples, respectively. VRE isolates showed ampicillin (n=11), ciprofloxacin (n=9), tetracycline (n=6), erythromycin (n=5), quinupristin/dalfopristin (n=3) and high-level kanamycin resistance (n=1). The tet(L) and/or tet(M) gene was found in all tetracycline-resistant isolates and the erm(B) gene in all erythromycin-resistant isolates. Three vanA-containing E. faecium and two E. gallinarum presented specific sequences of the Tn5397 transposon. Four VRE isolates harboured the ace virulence gene. One faecal sample revealed one ESBL-containing E. coli isolate that belongs to the A phylogenetic group, showed a phenotype of resistance to β-lactams and tetracycline, and harboured the bla (CTX-M-14), bla (SHV-12) and the tet(A) genes. To our knowledge, this is the first study to focus on defining the prevalence of VRE and/or ESBL-containing E. coli strains in wild birds from the Azores. The data recovered are essential to improve knowledge about the dissemination of resistant strains through wild ecosystems and their possible implications by transferring these resistances to other animals or to humans. PMID:21834624

  10. Variation in resistance traits, phylogenetic backgrounds, and virulence genotypes among Escherichia coli clinical isolates from adjacent hospital campuses serving distinct patient populations.

    Science.gov (United States)

    Drawz, Sarah M; Porter, Stephen; Kuskowski, Michael A; Johnston, Brian; Clabots, Connie; Kline, Susan; Ferrieri, Patricia; Johnson, James R

    2015-09-01

    Escherichia coli sequence type 13 (ST131), an emergent cause of multidrug-resistant extraintestinal infections, has important phylogenetic subsets, notably the H30 and H30Rx subclones, with distinctive resistance profiles and, possibly, clinical associations. To clarify the local prevalence of these ST131 subclones and their associations with antimicrobial resistance, ecological source, and virulence traits, we extensively characterized 233 consecutive E. coli clinical isolates (July and August 2013) from the University of Minnesota Medical Center-Fairview Infectious Diseases and Diagnostic Laboratory, Minneapolis, MN, which serves three adjacent facilities (a children's hospital and low- and high-acuity adult facilities). ST131 accounted for 26% of the study isolates (more than any other clonal group), was distributed similarly by facility, and was closely associated with ciprofloxacin resistance and extended-spectrum β-lactamase (ESBL) production. The H30 and H30Rx subclones accounted for most ST131 isolates and for the association of ST131 with fluoroquinolone resistance and ESBL production. Unlike ST131 per se, these subclones were distributed differentially by hospital, being most prevalent at the high-acuity adult facility and were absent from the children's hospital. The virulence gene profiles of ST131 and its subclones were distinctive and more extensive than those of other fluoroquinolone-resistant or ESBL-producing isolates. Within ST131, bla CTX-M-15 was confined to H30Rx isolates and other bla CTX-M variants to non-Rx H30 isolates. Pulsed-field gel electrophoresis documented a predominance of globally distributed pulsotypes and no local outbreak pattern. These findings help clarify the epidemiology, ecology, and bacterial correlates of the H30 and H30Rx ST131 subclones by documenting a high overall prevalence but significant segregation by facility, strong associations with fluoroquinolone resistance and specific ESBL variants, and distinctive

  11. Development of quinoxaline 1, 4-dioxides resistance in Escherichia coli and molecular change under resistance selection.

    Directory of Open Access Journals (Sweden)

    Wentao Guo

    Full Text Available Quinoxaline 1, 4-dioxides (QdNOs has been used in animals as antimicrobial agents and growth promoters for decades. However, the resistance to QdNOs in pathogenic bacteria raises worldwide concern but it is barely known. To explore the molecular mechanism involved in development of QdNOs resistance in Escherichia coli, 6 strains selected by QdNOs in vitro and 21 strains isolated from QdNOs-used swine farm were subjected to MIC determination and PCR amplification of oqxA gene. A conjugative transfer was carried out to evaluate the transfer risk of QdNOs resistant determinant. Furthermore, the transcriptional profile of a QdNOs-resistant E. coli (79O4-2 selected in vitro with its parent strain 79-161 was assayed with a prokaryotic suppression subtractive hybridization (SSH PCR cDNA subtraction. The result showed that more than 95% (20/21 clinical isolates were oqxA positive, while all the 6 induced QdNOs-resistant strains carried no oqxA gene and exhibited low frequency of conjugation. 44 fragments were identified by SSH PCR subtraction in the QdNOs-resistant strain 79O4-2. 18 cDNAs were involved in biosynthesis of Fe-S cluster (narH, protein (rpoA, trmD, truA, glyS, ileS, rplFCX, rpsH, fusA, lipoate (lipA, lipid A (lpxC, trehalose (otsA, CTP(pyrG and others molecular. The 11 cDNAs were related to metabolism or degradation of glycolysis (gpmA and pgi and proteins (clpX, clpA, pepN and fkpB. The atpADG and ubiB genes were associated with ATP biosynthesis and electron transport chain. The pathway of the functional genes revealed that E. coli may adapt the stress generated by QdNOs or develop specific QdNOs-resistance by activation of antioxidative agents biosynthesis (lipoate and trehalose, protein biosynthesis, glycolysis and oxidative phosphorylation. This study initially reveals the possible molecular mechanism involved in the development of QdNOs-resistance in E. coli, providing with novel insights in prediction and assessment of the emergency

  12. Epidemiological and clinical complexity of amoxicillin-clavulanate-resistant Escherichia coli.

    Science.gov (United States)

    Rodríguez-Baño, Jesús; Oteo, Jesús; Ortega, Adriana; Villar, Macarena; Conejo, M Carmen; Bou, Germán; Aranzamendi-Zaldumbide, Maitane; Cercenado, Emilia; Gurguí, Mercè; Martínez-Martínez, Luis; Merino, María; Rivera, Alba; Oliver, Antonio; Weber, Irene; Pascual, Alvaro; Bartolomé, Rosa M; Gónzalez-López, Juan José; Campos, José

    2013-07-01

    Two hundred twelve patients with colonization/infection due to amoxicillin-clavulanate (AMC)-resistant Escherichia coli were studied. OXA-1- and inhibitor-resistant TEM (IRT)-producing strains were associated with urinary tract infections, while OXA-1 producers and chromosomal AmpC hyperproducers were associated with bacteremic infections. AMC resistance in E. coli is a complex phenomenon with heterogeneous clinical implications. PMID:23637303

  13. Characterization of a novel tetracycline resistance that functions only in aerobically grown Escherichia coli.

    OpenAIRE

    Speer, B S; Salyers, A A

    1988-01-01

    A tetracycline resistance (Tcr) gene that was found originally on two Bacteroides plasmids (pBF4 and pCP1) confers tetracycline resistance on Escherichia coli, but only when it is grown aerobically. Using maxicells, we have identified a 44-kilodalton protein which is encoded by the region that carries the Tcr gene and which may be the Tcr gene product. Localization experiments indicate that this 44-kilodalton protein is cytoplasmic. To determine whether the tetracycline resistance gene is exp...

  14. No Development of Imipenem Resistance in Pneumonia Caused by Escherichia coli

    OpenAIRE

    Yayan, Josef; Ghebremedhin, Beniam; Rasche, Kurt

    2015-01-01

    Background: Antibiotic resistance continues to rise due to the increased number of antibiotic prescriptions and is now a major threat to public health. In particular, there is an increase in antibiotic resistance to Escherichia coli according to the latest reports. Trial Design: This article examines, retrospectively, antibiotic resistance in patients with community- and nosocomial-acquired pneumonia caused by E coli. Methods: The data of all patients with community- and nosocomial-acquired p...

  15. Antimicrobial-Resistant Escherichia coli in Public Beach Waters in Quebec

    Directory of Open Access Journals (Sweden)

    Patricia Turgeon

    2012-01-01

    Full Text Available INTRODUCTION: Human exposure to antimicrobial-resistant bacteria may result in the transfer of resistance to commensal or pathogenic microbes present in the gastrointestinal tract, which may lead to severe health consequences and difficulties in treatment of future bacterial infections. It was hypothesized that the recreational waters from beaches represent a source of antimicrobial-resistant Escherichia coli for people engaging in water activities.

  16. Lytic phages obscure the cost of antibiotic resistance in Escherichia coli

    OpenAIRE

    Tazzyman, Samuel J; Hall, Alex R

    2014-01-01

    The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under pha...

  17. Cross-resistance among cinoxacin, ciprofloxacin, DJ-6783, enoxacin, nalidixic acid, norfloxacin, and oxolinic acid after in vitro selection of resistant populations.

    OpenAIRE

    Barry, A. L.; Jones, R N

    1984-01-01

    Six different gram-negative bacilli were serially transferred through subinhibitory concentrations of seven quinolone derivatives or related organic acids. A gradual, stepwise decrease in susceptibility was noted with all seven drugs, and the resistant cultures demonstrated a concomitant cross-resistance to the other drugs.

  18. Cryptic tetracycline resistance determinant (class F) from Bacteroides fragilis mediates resistance in Escherichia coli by actively reducing tetracycline accumulation.

    OpenAIRE

    Park, B. H.; Hendricks, M; Malamy, M H; Tally, F P; Levy, S. B.

    1987-01-01

    Escherichia coli bearing a cryptic tetracycline resistance determinant from Bacteroides fragilis expressed low-level constitutive resistance to tetracycline under aerobic, but not anaerobic, growth conditions and accumulated less tetracycline aerobically than did isogenic susceptible cells. This decreased uptake was energy dependent and reversible by increased concentrations of tetracycline, suggesting a saturable carrier-mediated active efflux mechanism. Decreased uptake was not seen when th...

  19. Antimicrobial resistance, genotypic characterization and pulsed-field gel electrophoresis typing of extended spectrum β-lactamases-producing clinical Escherichia coli strains in Macao, China

    Institute of Scientific and Technical Information of China (English)

    YE Qian-hong; LAU Ying; LIANG Bin; TIAN Su-fei

    2011-01-01

    Background The rise of the production of CTX-M class extended spectrum β-lactamases (ESBLs) has been well documented in traveling countries but no data are found for Macao,an international travel city.The objectives of this study were to identify the antimicrobial resistance pattern,and determine the prevalence,genotype and clonal relationship of ESBLs in 209 clinical Escherichia coli strains from Macao,China.Methods Antimicrobial susceptibility test was performed to determine the resistance patterns of the isolates using the disk diffusion method with 17 antimicrobial agents.Phenotypic detection was screened and confirmed according to the Clinical and Laboratory Standards Institute.Genotypic characterization was detected by isoelectric focusing analysis,polymerase chain reaction and sequencing.The clonal relationship between the different ESBL isolates was studied by pulsed-field gel electrophoresis (PFGE).Results Imipenem and meropenem exhibited 100% susceptible among 209 strains.Overall,82.3%,67.3%,52.9%,51.2% and 51.0% of the isolates displayed resistance to ampicillin,tetracylcline,ciprofloxacin,sulfamethoxazole trimethoprin and gentamycin.The prevalence rate of ESBLs was 30.1%.Antibiotic resistances were found to be significantly higher among the ESBL producing group compared to non-ESBL producing group.We detected CTX-M-14 to be the major genotypic characterization of ESBLs (76.2%).Two strains showed indistinguishable patterns by PFGE.Conclusions The prevalence of antimicrobial resistance is alarming high in Macao.Antimicrobial resistance is significantly higher among the ESBL producing group.This study documented CTX-M-14 as the predominant ESBL type.Although indistinguishable pattern was found between two strains,it was too small to decide whether any of the investigated strains was epidemic.Our findings may be also pertinent for other geographic areas undergoing similar travel characteristics to understand the corresponding effects on bacterial

  20. Increasing antimicrobial resistance in Escherichia coli isolates from community-acquired urinary tract infections during 1998-2003 in Manisa, Turkey.

    Science.gov (United States)

    Kurutepe, Semra; Surucuoglu, Suheyla; Sezgin, Cenk; Gazi, Horu; Gulay, Mehmet; Ozbakkaloglu, Beril

    2005-06-01

    Urinary tract infections are among the most common infections with an increasing resistance to antimicrobials. The aim of this study was to determine the change in antimicrobial susceptibility of Escherichia coli isolates from patients with community-acquired urinary tract infection (UTI) for the years 1998 through 2003 and to suggest that the current empirical antibiotic therapy used for these patients is inappropriate. During the study period, 7,335 community urine samples of which 1,203 (16.4%) grew bacterial isolates were analyzed. Among the total of 1,203 isolates, 880 (73.2%) were E. coli. The range of resistance of E. coli to ampicillin was 47.8 to 64.6% and that to trimethoprim-sulfamethoxazole was 37.1 to 44.6% during the study period. The susceptibility pattern of E. coli to nitrofurantoin and cefuroxime did not vary significantly over the 6-year period. There was a significant increase in the susceptibility of E. coli to ciprofloxacin (11.3 - 26.7%), amoxicillin-clavulanate (18.4 - 29.2%) and gentamicin (7.0 - 25.6%) (P < 0.05). Empirical initial treatment with ampicillin and trimethoprim-sulfamethoxazole was thus inadequate in approximately half of UTI cases in our region. PMID:15973007

  1. Study on the genes of ciprofloxacin-resistance in Neissria gonorrhoeae epidemic strains in linfen region%淋病奈瑟菌对环丙沙星耐药性的基因研究

    Institute of Scientific and Technical Information of China (English)

    侯临平; 李连青; 徐勇全

    2010-01-01

    Objective To investigate the occurrence of ciprofloxacin(cip)-resistance among Neisseria gonorrhoeae strains in Linfen region in 2006 and determine the frequency and patterns of mutations in gyrA gene in the ciprofloxacin resistance isolates. Methods A total of 33 gonococcal isolates were collected in Linfen region for Neisseria gonorrhoeae. In vitro, susceptibility tests of ciprofloxacin were performed in 33 isolates, gyrA gene were amplified by polymerase chain reaction(PCR)assay and the PCR products were directly sequenced in order to see if there were mutations in gyrA gene. Results The 33 clinical isolates demonstrated 100% resistance to ciprofloxacin. The gyrA gene containing quinolone resistance-determining region (QRDR)were amplified by PCR in all clinical isolates. The mutations had amino acid substitutions of Ser to Phe at codon 91(33 strains),and Asp to Gly,Asn,Ala at codon 95 of gyrA respectively. The most common gyrA alteration at codon 95, Asp-95 to Gly was found in 19 strains (63.3 %). Conclusions The resistant strains of Neisseria gonorrhoeae to ciprofloxacin in Linfen region are serious. The results from this study suggested that mutations in gyrA gene play an important role in the development of fluoroquinolone resistance of Neisseria gonorrhoeae.%目的 探讨临汾地区淋病奈瑟菌对环丙沙星的耐药性及其与gyrA基因喹诺酮类耐药决定区(QRDR)之间的关系.方法 采集33例淋球菌感染标本,通过药敏试验筛选出对环丙沙星耐药菌株,设计对应于淋球菌gyrA上QRDR区基因片段的引物,经过聚合酶链式反应(PCR)扩增其目的 基因片段,并对扩增产物进行DNA序列测定.结果 33株淋病奈瑟菌临床分离株对环丙沙星全部耐药;所有耐药菌株均经PCR扩增出大小为225 bp(对应于QRDR)的基因片段;测序结果显示耐药菌株都发生了91位点突变(Ser-91→Phe),其中单独91位点突变的有3株,发生91和95双位点突变的有30株,95

  2. Valine-Resistant Escherichia coli K-12 Strains with Mutations in the ilvB Operon

    OpenAIRE

    Sutton, Ann; Newman, Thomas; Francis, Marilyn; Freundlich, Martin

    1981-01-01

    Escherichia coli K-12 mutants resistant to growth inhibition by valine were isolated. These strains contained mutations in the ilvB operon effecting either the regulation of acetohydroxy acid synthase I or the sensitivity of the enzyme to end product inhibition by valine.

  3. Mechanisms of antibiotic resistance to enrofloxacin in uropathogenic Escherichia coli in dog

    Science.gov (United States)

    Escherichia coli (E. coli) urinary tract infections (UTIs) are becoming a serious problem both for pets and humans (zoonosis) due to the close contact and to the increasing resistance to antibiotics. Canine E. coli represents a good experimental model useful to study this pathology. Moreover, as des...

  4. Hospitalization, a risk factor for antibiotic-resistant Escherichia coli in the community?

    NARCIS (Netherlands)

    Bruinsma, N; Filius, PMG; van den Bogaard, AE; Nys, S; Degener, J; Endtz, HP; Stobberingh, EE

    2003-01-01

    Objective: The impact of hospitalization on the prevalence of resistant Escherichia coli in the intestinal flora of patients admitted to the surgical wards of three Dutch university-affiliated hospitals was analysed prospectively. Methods: Faecal samples were obtained on admission to the hospital, a

  5. Colistin Resistance mcr-1-Gene-Bearing Escherichia coli Strain from the United States

    Science.gov (United States)

    Ladely, Scott R.; Plumblee, Jodie R.; Hall, M. Carolina; Simpson, Sheron A.; Ballard, Linda L.; Scheffler, Brian E.; Genzlinger, Linda L.; Cook, Kimberly L.

    2016-01-01

    Transmissible colistin resistance in the form of an mcr-1-gene-bearing plasmid has been recently reported in Enterobacteriaceae in several parts of the world. We report here the completed genome sequence of an Escherichia coli strain isolated from swine in the United States that carried the mcr-1 gene on an IncI2-type plasmid. PMID:27587816

  6. De novo acquisition of resistance to three antibiotics by Escherichia coli

    NARCIS (Netherlands)

    M.A. van der Horst; J.M. Schuurmans; M.C. Smid; B.B. Koenders; B.H. ter Kuile

    2011-01-01

    The acquisition of resistance to amoxicillin, tetracycline, and enrofloxacin by Escherichia coli MG 1655 was examined by exposing growing cells to constant or stepwise increasing concentrations of these compounds. The minimal inhibitory concentration (MIC) of E. coli for amoxicillin increased from 4

  7. Antimicrobial resistance in commensal Escherichia coli in veal calves is associated with antimicrobial drug use

    NARCIS (Netherlands)

    Bosman, A.B.; Wagenaar, J.A.; Stegeman, J.A.; Vernooij, J.C.M.; Mevius, D.J.

    2014-01-01

    The aim of this study was to determine the association between farm management factors, including antimicrobial drug usage, and resistance in commensal Escherichia coli isolates from the faeces of white veal calves. Ninety E. coli isolates from one pooled sample per farm (n = 48) were tested for the

  8. Evaluation of Eight Different Cephalosporins for Detection of Cephalosporin Resistance in Salmonella enterica and Escherichia coli

    NARCIS (Netherlands)

    Aarestrup, F.M.; Hasman, H.; Veldman, K.T.; Mevius, D.J.

    2010-01-01

    This study evaluates the efficacy of eight different cephalosporins for detection of cephalosporin resistance mediated by extended spectrum beta-lactamases (ESBL) and plasmidic AmpC beta-lactamases in Salmonella and Escherichia coli. A total of 138 E. coli and 86 Salmonella isolates with known beta-

  9. Association between antimicrobial resistance and virulence genes in Escherichia coli obtained from blood and faeces

    DEFF Research Database (Denmark)

    Bagger-Skjøt, Line; Sandvang, Dorthe; Frimodt-Møller, Niels;

    2007-01-01

    Escherichia coli isolates obtained from faeces (n = 85) and blood (n = 123) were susceptibility tested against 17 antimicrobial agents and the presence of 9 virulence genes was determined by PCR. Positive associations between several antimicrobial resistances and 2 VF genes (iutA and traT) were...

  10. Virulence factors and drug resistance in Escherichia coli isolated from extraintestinal infections

    OpenAIRE

    Sharma S; Bhat G; Shenoy S

    2007-01-01

    Purpose: To determine the virulence factors produced by Escherichia coli isolated from extraintestinal infections, to study the drug resistance pattern in E. coli with special reference to extended spectrum β -lactamase (ESBL) and to evaluate screening methods for ESBL. Methods: A total of 152 isolates of E. coli from various extraintestinal infections were screened for virulence factors such as haemolysin, surface hydrophobicity, serum resistance and protease. All the isolates ...

  11. Role of outer membrane barrier in efflux-mediated tetracycline resistance of Escherichia coli.

    OpenAIRE

    Thanassi, D. G.; Suh, G S; Nikaido, H

    1995-01-01

    Accumulation of tetracycline in Escherichia coli was studied to determine its permeation pathway and to provide a basis for understanding efflux-mediated resistance. Passage of tetracycline across the outer membrane appeared to occur preferentially via the porin OmpF, with tetracycline in its magnesium-bound form. Rapid efflux of magnesium-chelated tetracycline from the periplasm was observed. In E. coli cells that do not contain exogenous tetracycline resistance genes, the steady-state level...

  12. Colonization with Extraintestinal Pathogenic Escherichia coli among Nursing Home Residents and Its Relationship to Fluoroquinolone Resistance

    Science.gov (United States)

    Maslow, Joel N.; Lautenbach, Ebbing; Glaze, Thomas; Bilker, Warren; Johnson, James R.

    2004-01-01

    In a cross-sectional fecal prevalence survey involving 49 residents of a Veterans Affairs nursing home, 59% of subjects were colonized with extraintestinal pathogenic Escherichia coli (ExPEC), 22% were colonized with adhesin-positive E. coli, and 51% were colonized with fluoroquinolone-resistant E. coli. Among 80 unique isolates, adhesins correlated negatively and aerobactin correlated positively with fluoroquinolone resistance. PMID:15328142

  13. Wastewater as a Source of Carbapenem Resistant Escherichia coli

    Science.gov (United States)

    Clinical studies have reported that the occurrence of carbapenem resistant E. coli is on the rise. This is of concern because carbapenem antibiotics are typically reserved for treating infections caused by bacteria resistant to other classes of antibiotics. Current literature st...

  14. Susceptibilities of Campylobacter jejuni Isolates from Germany to Ciprofloxacin, Moxifloxacin, Erythromycin, Clindamycin, and Tetracycline

    OpenAIRE

    Wagner, Jutta; Jabbusch, Miriam; Eisenblätter, Martin; Hahn, Helmut; Wendt, Constanze; Ignatius, Ralf

    2003-01-01

    To elucidate Campylobacter jejuni resistance to antibiotics in Germany, MICs of ciprofloxacin, moxifloxacin, erythromycin, clindamycin, and tetracycline were determined (using agar dilution) for 144 clinical isolates. The data indicate a considerable ciprofloxacin resistance (45.1%) without a clonal relationship of the strains and a greater in vitro activity of moxifloxacin, erythromycin, and clindamycin.

  15. Fluoroquinolone-resistant Escherichia coli Carriage in Long-Term Care Facility

    OpenAIRE

    Maslow, Joel N.; Lee, Betsy; Lautenbach, Ebbing

    2005-01-01

    We conducted a cross-sectional study to determine the prevalence of, and risk factors for, colonization with fluoroquinolone (FQ)-resistant Escherichia coli in residents in a long-term care facility. FQ-resistant E. coli were identified from rectal swabs for 25 (51%) of 49 participants at study entry. On multivariable analyses, prior FQ use was the only independent risk factor for FQ-resistant E. coli carriage and was consistent for FQ exposures in the previous 3, 6, 9, or 12 months. Pulsed-f...

  16. High levels of antimicrobial resistance among escherichia coli isolates from livestock farms and synanthropic rats and shrews in the Mekong Delta of Vietnam.

    Science.gov (United States)

    Nhung, N T; Cuong, N V; Campbell, J; Hoa, N T; Bryant, J E; Truc, V N T; Kiet, B T; Jombart, T; Trung, N V; Hien, V B; Thwaites, G; Baker, S; Carrique-Mas, J

    2015-02-01

    In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ∼8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R(2) range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R(2) range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. PMID:25398864

  17. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    F Amin Harati

    2012-12-01

    Full Text Available Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has increased in community acquired methicillin-resistant S. aureus strains. The aim of this study was to evaluate the minimum inhibitory concentration of ciprofloxacin and hexahydroquino-line derivatives against methicillin- and ciprofloxacin-resistant S. aureus.Methods: Identification of S. aureus was performed by routine microbiological tests in the Department of Pathobiology in Winter 2012. The susceptibility of S. aureus strains to both methicillin and ciprofloxacin was examined by the Kirby-Bauer disk-diffusion method. The minimum inhibitory concentration of ciprofloxacin, hexahydroquinoline derivatives and their combination were separately determined by broth microdilution method against methicillin- and ciprofloxacin-resistant S. aureus.Results: The minimum inhibitory concentration of ciprofloxacin decreased in the presence of hexahydroquinolinein derivatives in comparison with ciprofloxacin alone.Conclusion: This study showed that hexahydroquinoline derivatives enhance the antibacterial effect of ciprofloxacin against methicillin- and ciprofloxacin-resistant S. aureus. Therefore, these derivatives could be used as inhibitors of antibiotic resistance in combination therapies. This enhancement may be related to the inhibitory effect of hexahydroquinoline derivatives on the expression of antibiotic efflux pump in the bacteria. However, the structural features of a fluoroquinolone that determine whether it is affected by efflux transporters are not fully

  18. Resistance of Escherichia coli, the most frequent cause of urinary tract infection in children, to antibiotics

    Directory of Open Access Journals (Sweden)

    Stojanović Vesna

    2010-01-01

    Full Text Available Introduction. Urinary tract infections (UTI take the second place in the incidence of bacterial infection in children. Escherichia coli is a cause of infection in 85-90%. A periodic evaluation of the resistance to antimicrobial drugs has to be performed in each geographic region, since investigations confirmed that the resistance of bacteria causing UTI has been in progress. Material and methods. A retrospective investigation has been performed, comprising the two time periods in the range of 10 years in order to identify the prevalence and resistance of the bacteria causing UTI in the patients treated at the Department of Nephrology of Institute for Child and Youth Health Care of Vojvodina. Results. During the first investigated period from January 1996 up to December 1997, there were 163 urin analyses performed vs 134 urine analyses in the second period, starting from January 2006 to December 2007. In both periods, Escherichia coli, was the most frequent cause of UTI (82.1% in 1996/97 vs 86.50% in 2006/07. During this ten-year period, the resistance of Escherichia coli increased both to ampicillin (from 53% to 69% (p>0.05 and to trimethoprim/sulfamethoxazole (34% vs 55%; p<0.05 as well as to cephalexin (4% vs 36%; p<0.05 which has been lately used in our region as a drug of choice in empiric therapy of the suspect UTI. Discussion. There have been records on a slow increase of the Escherichia coli resistance to ceftazidim, gentamycin and nalidixic acid, but significant increase to ampicillin, trimethoprim/sulfamethoxazole and cephalexin. Conclusion. For the initial therapy of UTI in the Province of Vojvodina we recommend: per orally - cephalosporins I, II and III generation, and in case when the child is not capable to get therapy perorally, or in the case of highly febrile infant - cephalosporins III generation parenterally.

  19. Uptake of ciprofloxacin by macrophages.

    OpenAIRE

    Easmon, C. S.; Crane, J P

    1985-01-01

    Ciprofloxacin was concentrated within mouse peritoneal macrophages to between two and three times extracellular values. Uptake was rapid, occurred equally well with dead cells, and was not affected by lowering the pH or by prior ingestion of Staphylococcus aureus. Intracellular staphylococci were killed by extracellular concentrations of ciprofloxacin as low as 0.5 mg/l.

  20. Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children

    Directory of Open Access Journals (Sweden)

    This paper should be cited as: Sedighi I, Alikhani MY, Nakhaee S, Karami P . [ Antibiotic Resistance Patterns in Enteric and Uropathogenic Strains of Escherichia Coli in Children ]. mlj goums . 201 4 ; 8 ( Suppl 4 : 42 - 48 [Article in Per sian] Sedi ghi, I. (MD

    2014-11-01

    Full Text Available Background and Objective: Escherichia coli is the most common cause of urinary tract infections in children and the leading cause of intra-abdominal infections (peritonitis and abscess followed intestinal injuries. Urinary tract infection, including cystitis and pyelonephritis, is a common childhood infection. E. coli causes more than 90 percent of the community acquired and 50% of hospital acquired urinary tract infections; therefore, the determination of E. coli antibiotic susceptibility is a paramount importance to clinical and epidemiological purposes. Material and Methods: In this cross-sectional study, 50 E. coli strains isolated from urine samples of children less than 7 years of age with urinary tract infections. They were compared for drug susceptibility testing by disc diffusion method with 50 strains of Escherichia coli isolated from stool samples of healthy children with the same age and sex pattern. Results: The actual amount of drug sensitivity of uropathogenic and intestinal Escherichia coli strains to amikacin was 94 and 100%, nitrofurantoin 90 and 88%, gentamicin 66 and 94%, cefixime 56 and 60%, nalidixic acid 38 and 44% and to cotrimoxazole 28 and 32%, respectively. Conclusion: the rate of resistance to gentamicin, Cefixime and nalidixic acid in urinary tract infection isolates were more than intestinal strains. The highest rate of drug resistance in urinary Escherichia coli isolates was associated with cotrimoxazole and the lowest one with amikacin.

  1. Antibiotic resistance patterns in Escherichia coli from gulls in nine European countries

    Directory of Open Access Journals (Sweden)

    Johan Stedt

    2014-01-01

    Full Text Available Background: The prevalence of antibiotic resistant faecal indicator bacteria from humans and food production animals has increased over the last decades. In Europe, resistance levels in Escherichia coli from these sources show a south-to-north gradient, with more widespread resistance in the Mediterranean region compared to northern Europe. Recent studies show that resistance levels can be high also in wildlife, but it is unknown to what extent resistance levels in nature conform to the patterns observed in human-associated bacteria. Methods: To test this, we collected 3,158 faecal samples from breeding gulls (Larus sp. from nine European countries and tested 2,210 randomly isolated E. coli for resistance against 10 antibiotics commonly used in human and veterinary medicine. Results: Overall, 31.5% of the gull E. coli isolates were resistant to ≥1 antibiotic, but with considerable variation between countries: highest levels of isolates resistant to ≥1 antibiotic were observed in Spain (61.2% and lowest levels in Denmark (8.3%. For each tested antibiotic, the Iberian countries were either the countries with the highest levels or in the upper range in between-country comparisons, while northern countries generally had a lower proportion of resistant E. coli isolates, thereby resembling the gradient of resistance seen in human and food animal sources. Conclusion: We propose that gulls may serve as a sentinel of environmental levels of antibiotic resistant E. coli to complement studies of human-associated microbiota.

  2. Multiple-dose pharmacokinetics of concurrent oral ciprofloxacin and rifampin therapy in elderly patients.

    OpenAIRE

    Chandler, M H; Toler, S M; Rapp, R P; Muder, R R; Korvick, J A

    1990-01-01

    The purpose of this clinical study was to investigate the influence of concomitant drug therapy with ciprofloxacin and rifampin on the individual pharmacokinetic profile of each agent in elderly patients. Twelve nursing home patients (age, 74 +/- 7 years), colonized with methicillin-resistant Staphylococcus aureus, were randomized to receive 14-day therapy with oral ciprofloxacin (750 mg every 12 h) (group A; n = 6) or ciprofloxacin (750 mg every 12 h) and oral rifampin (300 mg every 12 h) (g...

  3. Effect of Ciprofloxacin on Killing of Actinobacillus actinomycetemcomitans by Polymorphonuclear Leukocytes

    OpenAIRE

    Cacchillo, David A.; Walters, John D.

    2002-01-01

    Actinobacillus actinomycetemcomitans, a pathogen associated with aggressive periodontitis, resists phagocytic killing by polymorphonuclear leukocytes (PMNs). It is susceptible to ciprofloxacin, which PMNs actively accumulate. This study tested the hypothesis that ciprofloxacin-loaded PMNs are more effective at killing A. actinomycetemcomitans than control PMNs. Isolated human PMNs were loaded by brief incubation with 0.5 μg of ciprofloxacin/ml. Opsonized bacteria (ATCC 43718) were incubated a...

  4. Quantitative assessment of faecal shedding of β-lactam-resistant Escherichia coli and enterococci in dogs

    DEFF Research Database (Denmark)

    Gongora, Carmen Espinosa; Shah, Syed Qaswar Ali; Jessen, Lisbeth Rem;

    2015-01-01

    Quantitative data on faecal shedding of antimicrobial resistant bacteria are crucial to assess the risk of transmission from dogs to other animals as well as humans. In this study we investigated prevalence and concentrations of β-lactam-resistant Escherichia coli and enterococci in the faeces...... of 108 dogs presenting at a veterinary hospital in Denmark. The dogs had not been treated with antimicrobials for 4 weeks prior to the study. Total E. coli and enterococci were quantified by counts on MacConkey and Slanetz-Bartley, respectively. Resistant E. coli and enterococci were counted on the same...... media containing relevant antibiotic concentrations, followed by species identification using MALDI-TOF. Ampicillin- and cefotaxime-resistant E. coli were detected in 40% and 8% of the dogs, respectively, whereas approximately 15% carried ampicillin-resistant enterococci, mainly Enterococcus faecium...

  5. Association Between Tetracycline Consumption and Tetracycline Resistance in Escherichia coli from Healthy Danish Slaughter Pigs

    DEFF Research Database (Denmark)

    Vieira, Antonio; Houe, Hans; Wegener, Henrik Caspar;

    2009-01-01

    performed for the risk factors in relation to the susceptibility status. Logistic regression analysis was performed to identify risk factors with significant effect on the log odds of tetracycline resistance of E. coli isolates. The model showed that an increase in the interval between last prescription...... and sampling date would decrease the probability of isolating a resistant F. coli isolate (p-value = 0.01). Also, a direct association between treatment incidence rate in a herd and probability of resistance was detected (p-value = 0.03). Other risk factors found to have a significant effect in the isolate......It has been recognized that exposure to antimicrobial agents can exert a selective pressure for the emergence of antimicrobial resistance. The objective of this study was to investigate an association between the probability of isolating a tetracycline-resistant Escherichia coli isolate from...

  6. Antibiotic resistance and plasmid carriage among Escherichia coli isolates from chicken meat in Malaysia

    International Nuclear Information System (INIS)

    Escherichia coli isolates from 131 raw chicken meat samples were tested for susceptibility to 12 antibiotics. Plasmids were isolated from many samples and their DNA molecular weight calculated. An 81.7% plasmid occurrence rate was observed among the isolates, ranging from 0 to 8 in number and with sizes from 1.2 to 118.6 MDa. Plasmids were detected in 93.8% of E. coIi isolates resistant to all 12 antibiotics, and in 90.5% of E. coli isolates resistant to 11. Three (2.8%) isolates harboured 8 plasmids and were resistant to all 12 antibiotics. Antibiotic resistant genes in bacteria are usually carried in extrachromosomal DNA and it is postulated that E. coli with a high number of plasmids possesses wider resistance to antibiotics. (author)

  7. Surveillance of antimicrobial resistance in Escherichia coli strains isolated from pigs at Spanish slaughterhouses.

    Science.gov (United States)

    Teshager, T; Herrero, I A; Porrero, M C; Garde, J; Moreno, M A; Domínguez, L

    2000-07-01

    Antimicrobial resistance can make the efficient treatment of bacterial infections in humans and animals more difficult. Antimicrobial use in food animals may be one of the factors contributing to resistance. The Spanish surveillance network VAV has established a baseline of antimicrobial resistance in Escherichia coli strains from healthy pigs. Minimum inhibitory concentration and patterns of resistance to antimicrobials used in animals and humans were determined for 205 faecal strains isolated in a sampling frame of four slaughterhouses in Spain from 220 pigs in 1998. Higher levels of resistance were seen against antimicrobial agents authorised for use in food animals especially tetracycline, sulphonamides, trimethoprim and amoxycillin. All isolates were susceptible to antimicrobials employed mainly in humans such as ceftazidime, cefotaxime, imipenem, aztreonam and amikacin.

  8. Human Health Hazards from Antimicrobial-Resistant Escherichia coli of Animal Origin

    DEFF Research Database (Denmark)

    Hammerum, A. M.; Heuer, Ole Eske

    2009-01-01

    Because of the intensive use of antimicrobial agents in food animal production, meat is frequently contaminated with antimicrobial-resistant Escherichia coli. Humans can be colonized with E. coli of animal origin, and because of resistance to commonly used antimicrobial agents, these bacteria may...... cause infections for which limited therapeutic options are available. This may lead to treatment failure and can have serious consequences for the patient. Furthermore, E. coli of animal origin may act as a donor of antimicrobial resistance genes for other pathogenic E. coli. Thus, the intensive use...... of antimicrobial agents in food animals may add to the burden of antimicrobial resistance in humans. Bacteria from the animal reservoir that carry resistance to antimicrobial agents that are regarded as highly or critically important in human therapy (e.g., aminoglycosides, fluoroquinolones, and third- and fourth...

  9. Antibiotic Resistance in Escherichia coli from Pigs in Organic and Conventional Farming in Four European Countries

    DEFF Research Database (Denmark)

    Österberg, Julia; Wingstrand, Anne; Jensen, Annette Nygaard;

    2016-01-01

    Organic pig production differs in many ways from conventional production of pigs, e.g., in antibiotic use, herd structure, feeding regimes, access to outdoor areas and space allowance per pig. This study investigated if these differences result in a lower occurrence of antibiotic resistance...... in organic slaughter pigs in Denmark, France, Italy and Sweden. Samples were taken from the colon content and/or faeces and minimum inhibitory concentrations (MIC) of ten antibiotics were determined in isolates of Escherichia coli. In addition, the proportion of tetracycline (TET) resistant E. coli in colon...... in conventional pigs, except in Sweden where TET-resistance was equally low in both production types. There were also differences between countries within production type in the percentage resistance to individual antibiotics as well as the proportion of TET-resistant E. coli with lower median proportions...

  10. Ciprofloxacin induced erythema multiforme: a case report

    Directory of Open Access Journals (Sweden)

    K. M. Narasimhamurthy

    2015-06-01

    Full Text Available Erythema multiforme (EM is an acute, self-limited, and sometimes recurring skin condition that is considered to be a type IV hypersensitivity reaction associated with certain infections, medications, and other various triggers like flavorings and preservatives, such as benzoic acid and cinnamon, immunologic disorders, such as transient selective C4 deficiency of infancy, collagen diseases, vasculitides, sarcoidosis, non-Hodgkin lymphoma, leukemia, multiple myeloma, myeloid metaplasia, and polycythemia, physical or mechanical factors, such as tattooing, radiotherapy, cold, and sunlight, foods, including salmon berries and margarine, malignancy, and hormonal. EM may be present within a wide spectrum of severity. EM minor represents a localized eruption of the skin with minimal or no mucosal involvement. According to a consensus definition, Stevens-Johnson syndrome (SJS was separated from the EM spectrum and added to toxic epidermal necrolysis (TEN. The two spectra are now divided into the following: (1 EM consisting of erythema minor and major and (2 SJS/TEN. Ciprofloxacin is a second generation fluoroquinolone. Fluoroquinolones are rapidly bactericidal in vitro and are considerably potent against Escherichia coli and various species of Salmonella, Shigella, Enterobacter, Campylobacter, and Neisseria. Mainly used in urinary tract infections, prostatitis, sexually transmitted diseases, gastrointestinal and abdominal infections, respiratory tract infections, bone-joint and soft tissue infections. Metronidazole is a nitroimidazole antimicrobial medication used particularly for anaerobic bacteria and protozoa. It is on the World Health Organizations list of essential medicines, a list of the most important medications needed in a basic health system. Here we report the case of a 39-year-old male patient who presented with EM to the dermatology outpatient department, Adichunchanagiri Hospital and Research Centre. The patient gave a history of taking

  11. Efficient Recovery of Fluoroquinolone-Susceptible and Fluoroquinolone-Resistant Escherichia coli Strains From Frozen Samples

    OpenAIRE

    Lautenbach, Ebbing; Santana, Evelyn; Lee, Abby; Tolomeo, Pam; Black, Nicole; Babson, Andrew; Perencevich, Eli N.; Harris, Anthony D; Smith, Catherine A; Maslow, Joel

    2008-01-01

    We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only i...

  12. Effects of in-feed chlortetracycline prophylaxis of beef cattle on animal health and antimicrobial-resistant Escherichia coli

    Science.gov (United States)

    Concerns have been raised that in-feed chlortetracycline (CTC) may increase antimicrobial resistance (AMR), specifically tetracycline-resistant (TETr) Escherichia coli, and third-generation cephalosporin-resistant (3GCr) E. coli. We evaluated the impact of a 5-day in-feed CTC prophylaxis on animal h...

  13. Nickel and Cobalt Resistance Engineered in Escherichia coli by Overexpression of Serine Acetyltransferase from the Nickel Hyperaccumulator Plant Thlaspi goesingense

    OpenAIRE

    Freeman, John L; Persans, Michael W.; Nieman, Ken; Salt, David E.

    2005-01-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproducti...

  14. Comparison of antimicrobial resistant Escherichia coli in wild and captive Japanese serows.

    Science.gov (United States)

    Kinjo, T; Minamoto, N; Sugiyama, M; Sugiyama, Y

    1992-10-01

    The fecal Escherichia coli isolated from wild Japanese serows living in mountainous areas away from humans and those from captive serows kept in human areas were examined for antimicrobial resistance and the possession of transferable R plasmids. Of 874 E. coli strains isolated from 283 wild serows in 1980-1981, only 11 (1.3%) were resistant to at least one of 6 antimicrobial drugs; ampicillin, streptomycin, tetracycline, chloramphenicol, kanamycin and sulfadimethoxin. Seven (2.5%) individuals were found to carry resistant E. coli. To heighten the isolation frequency of drug-resistant strains, fecal samples of 244 wild serows in 1983-1984 were cultured directly onto drug-supplemented media. Only 12 (4.9%) serows were shown to have drug-resistant E. coli. No transferable R plasmid was detected among a total of 87 resistant strains from wild serows. In contrast, all 33 captive serows except one which was kept only one day after capture, showed resistant E. coli and 20 (60.6%) serows were excreting R plasmid-carrying E. coli. Of 161 drug-resistant strains from captive serows, 50 (31.1%) were found to carry R plasmids. Wild serows seemed to readily change to harbor resistant E. coli almost as soon they were reared in human areas without direct exposure to drugs. These results lead to the conclusion that drug-resistant E. coli can probably be used as microbial indicator for natural environmental pollution. PMID:1420561

  15. Lytic phages obscure the cost of antibiotic resistance in Escherichia coli.

    Science.gov (United States)

    Tazzyman, Samuel J; Hall, Alex R

    2015-04-01

    The long-term persistence of antibiotic-resistant bacteria depends on their fitness relative to other genotypes in the absence of drugs. Outside the laboratory, viruses that parasitize bacteria (phages) are ubiquitous, but costs of antibiotic resistance are typically studied in phage-free experimental conditions. We used a mathematical model and experiments with Escherichia coli to show that lytic phages strongly affect the incidence of antibiotic resistance in drug-free conditions. Under phage parasitism, the likelihood that antibiotic-resistant genetic backgrounds spread depends on their initial frequency, mutation rate and intrinsic growth rate relative to drug-susceptible genotypes, because these parameters determine relative rates of phage-resistance evolution on different genetic backgrounds. Moreover, the average cost of antibiotic resistance in terms of intrinsic growth in the antibiotic-free experimental environment was small relative to the benefits of an increased mutation rate in the presence of phages. This is consistent with our theoretical work indicating that, under phage selection, typical costs of antibiotic resistance can be outweighed by realistic increases in mutability if drug resistance and hypermutability are genetically linked, as is frequently observed in clinical isolates. This suggests the long-term distribution of antibiotic resistance depends on the relative rates at which different lineages adapt to other types of selection, which in the case of phage parasitism is probably extremely common, as well as costs of resistance inferred by classical in vitro methods. PMID:25268496

  16. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production

    OpenAIRE

    Solveig Sølverød Mo; Jannice Schau Slettemeås; Einar Sverre Berg; Madelaine Norström; Marianne Sunde

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the bla CMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare bla CMY-2 containing Escherichia coli isolated from the intestinal flora of broilers ...

  17. A novel, double mutation in DNA gyrase A of Escherichia coli conferring resistance to quinolone antibiotics.

    OpenAIRE

    Truong, Q C; Nguyen Van, J C; Shlaes, D; Gutmann, L; Moreau, N J

    1997-01-01

    A spontaneous Escherichia coli mutant, named Q3, resistant to nalidixic acid was obtained from a previously described clinical isolate of E. coli, Q2, resistant to fluoroquinolones but susceptible to nalidixic acid (E. Cambau, F. Bordon, E. Collatz, and L. Gutmann, Antimicrob. Agents Chemother. 37:1247-1252, 1993). Q3 harbored the mutation Asp82Gly in addition to the Gly81Asp mutation of Q2. The different mutations leading to Gly81Asp, Asp82Gly, and Gly81AspAsp82Gly were introduced into the g...

  18. Antibiotic Resistance in Escherichia Coli Strains Isolated from Urine of Inpatients and Outpatients

    Directory of Open Access Journals (Sweden)

    Abolfazl Davoodabadi

    2012-08-01

    Full Text Available The urinary tract infections regarded as a health problem around the world and not only as an agent of nosocomial infections but also infections in the community. Community acquired UTIs cause significant illness in the first 2 years of life [1]. Urinary tract infections in both inpatient and outpatient are common and widespread use of antibiotics is often the cause of emerging one or more antibiotic-resistant microorganisms [2]. Most studies have shown higher antibiotic resistance in bacterial strains isolated from hospitalized patients than outpatients. In this study, antibiogram was performed using disk diffusion susceptibility method according to NCCLS standards of the International Committee [3]. 8 different antibiotics, including ciprofloxacin (CP: 30 μg, ceftriaxone (CRO: 30 μg, cephalotin (CF: 30 μg, cefixime (CFM: 5 μg, cotrimoxazole (SXT, nalidixic acid (NA: 30 μg, nitrofurantoin (FM: 300 μg, gentamicin (GM: 10 μg were used for antibiogram. During 1388 the total number of urine samples sent to hospital microbiology laboratories valiasr (aj of Arak was 5156, of which 446 samples (65.8% were positive for E. coli culture.

  19. Biodegradation of ciprofloxacin in water and soil and its effects on the microbial communities

    Energy Technology Data Exchange (ETDEWEB)

    Girardi, Cristobal, E-mail: cristobal.girardi-lavin@ufz.de [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstrasse 15, 04318 Leipzig (Germany); Greve, Josephine [Minnesota State University, Mankato, MN 56001 8400 (United States); Lamshoeft, Marc [Institute of Environmental Research (INFU), TU Dortmund University, Otto-Hahn-Str. 6, NRW 44221 Dortmund (Germany); Fetzer, Ingo [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Microbiology, Permoserstrasse 15, 04318 Leipzig (Germany); Miltner, Anja [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstrasse 15, 04318 Leipzig (Germany); Schaeffer, Andreas [Department of Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology V), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kaestner, Matthias [UFZ - Helmholtz Centre for Environmental Research, Department of Environmental Biotechnology, Permoserstrasse 15, 04318 Leipzig (Germany)

    2011-12-30

    Highlights: Black-Right-Pointing-Pointer Mineralisation of toxic pollutants can be higher in soil than in water. Black-Right-Pointing-Pointer Ciprofloxacin affects the microbial communities and activities in soil. Black-Right-Pointing-Pointer Toxicity of ciprofloxacin is reduced in soil due to sorption processes. Black-Right-Pointing-Pointer Despite the buffering capacity of soil, ciprofloxacin remains active. Black-Right-Pointing-Pointer Ciprofloxacin resistance can develop in soils contaminated with this antibiotic. - Abstract: While antibiotics are frequently found in the environment, their biodegradability and ecotoxicological effects are not well understood. Ciprofloxacin inhibits active and growing microorganisms and therefore can represent an important risk for the environment, especially for soil microbial ecology and microbial ecosystem services. We investigated the biodegradation of {sup 14}C-ciprofloxacin in water and soil following OECD tests (301B, 307) to compare its fate in both systems. Ciprofloxacin is recalcitrant to biodegradation and transformation in the aqueous system. However, some mineralisation was observed in soil. The lower bioavailability of ciprofloxacin seems to reduce the compound's toxicity against microorganisms and allows its biodegradation. Moreover, ciprofloxacin strongly inhibits the microbial activities in both systems. Higher inhibition was observed in water than in soil and although its antimicrobial potency is reduced by sorption and aging in soil, ciprofloxacin remains biologically active over time. Therefore sorption does not completely eliminate the effects of this compound.

  20. Biodegradation of ciprofloxacin in water and soil and its effects on the microbial communities

    International Nuclear Information System (INIS)

    Highlights: ► Mineralisation of toxic pollutants can be higher in soil than in water. ► Ciprofloxacin affects the microbial communities and activities in soil. ► Toxicity of ciprofloxacin is reduced in soil due to sorption processes. ► Despite the buffering capacity of soil, ciprofloxacin remains active. ► Ciprofloxacin resistance can develop in soils contaminated with this antibiotic. - Abstract: While antibiotics are frequently found in the environment, their biodegradability and ecotoxicological effects are not well understood. Ciprofloxacin inhibits active and growing microorganisms and therefore can represent an important risk for the environment, especially for soil microbial ecology and microbial ecosystem services. We investigated the biodegradation of 14C-ciprofloxacin in water and soil following OECD tests (301B, 307) to compare its fate in both systems. Ciprofloxacin is recalcitrant to biodegradation and transformation in the aqueous system. However, some mineralisation was observed in soil. The lower bioavailability of ciprofloxacin seems to reduce the compound's toxicity against microorganisms and allows its biodegradation. Moreover, ciprofloxacin strongly inhibits the microbial activities in both systems. Higher inhibition was observed in water than in soil and although its antimicrobial potency is reduced by sorption and aging in soil, ciprofloxacin remains biologically active over time. Therefore sorption does not completely eliminate the effects of this compound.

  1. Antibiotic Selection of Escherichia coli Sequence Type 131 in a Mouse Intestinal Colonization Model

    OpenAIRE

    Boetius Hertz, Frederik; Løbner-Olesen, Anders; Frimodt-Møller, Niels

    2014-01-01

    The ability of different antibiotics to select for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli remains a topic of discussion. In a mouse intestinal colonization model, we evaluated the selective abilities of nine common antimicrobials (cefotaxime, cefuroxime, dicloxacillin, clindamycin, penicillin, ampicillin, meropenem, ciprofloxacin, and amdinocillin) against a CTX-M-15-producing E. coli sequence type 131 (ST131) isolate with a fluoroquinolone resistance phenotype. Mice ...

  2. Monitoring and Analysis on Multi Drug Resistance of Escherichia coli from Captive Population Amur Tiger

    Institute of Scientific and Technical Information of China (English)

    Xue; Yuan; Li; Fengyong; Sun; Jing; Cai; Longhui; Wu; Qingming; Zhou; Ming; Huang; Xianguang; Hua; Yuping

    2014-01-01

    In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.

  3. Multirresistência antimicrobiana em cepas de Escherichia coli isoladas de cadelas com piometra Antimicrobial multi-resistance of Escherichia coli strains isolated from bitches with pyometra

    Directory of Open Access Journals (Sweden)

    V.M. Lara

    2008-08-01

    Full Text Available The antimicrobial sensibility of Escherichia coli strains isolated from the uterine content of bitches was evaluated. Fifteen E. coli strains were tested in relation to their susceptibility to different antimicrobials. The results demonstrated 100% of resistance to all tested drugs, being a quite conflicting finding compared to other works, which observed variable resistance of those bacteria to different antimicrobials but not the same multi-resistance pattern. The detection of those multi-resistance strains configures a problem, with important implications on the antimicrobial therapy. Therefore, additional investigations for a best characterization and extension of this problem are needed.

  4. Proteomics for Drug Resistance on the Food Chain? Multidrug-Resistant Escherichia coli Proteomes from Slaughtered Pigs.

    Science.gov (United States)

    Ramos, Sónia; Silva, Nuno; Hébraud, Michel; Santos, Hugo M; Nunes-Miranda, Júlio Dinis; Pinto, Luís; Pereira, José E; Capelo, José-Luis; Poeta, Patrícia; Igrejas, Gilberto

    2016-06-01

    Understanding global drug resistance demands an integrated vision, focusing on both human and veterinary medicine. Omics technologies offer new vistas to decipher mechanisms of drug resistance in the food chain. For example, Escherichia coli resistance to major antibiotics is increasing whereas multidrug resistance (MDR) strains are now commonly found in humans and animals. Little is known about the structural and metabolic changes in the cell that trigger resistance to antimicrobial agents. Proteomics is an emerging field that is used to advance our knowledge in global health and drug resistance in the food chain. In the present proteomic analysis, we offer an overview of the global protein expression of different MDR E. coli strains from fecal samples of pigs slaughtered for human consumption. A full proteomic survey of the drug-resistant strains SU60, SU62, SU76, and SU23, under normal growth conditions, was made by two-dimensional electrophoresis, identifying proteins by MALDI-TOF/MS. The proteomes of these four E. coli strains with different genetic profiles were compared in detail. Identical transport, stress response, or metabolic proteins were discovered in the four strains. Several of the identified proteins are essential in bacterial pathogenesis (GAPDH, LuxS, FKBPs), development of bacterial resistance (Omp's, TolC, GroEL, ClpB, or SOD), and potential antibacterial targets (FBPA, FabB, ACC's, or Fab1). Effective therapies against resistant bacteria are crucial and, to accomplish this, a comprehensive understanding of putative resistance mechanisms is essential. Moving forward, we suggest that multi-omics research will further improve our knowledge about bacterial growth and virulence on the food chain, especially under antibiotic stress.

  5. Class 1 and 2 integrons, sul resistance genes and antibiotic resistance in Escherichia coli isolated from Dongjiang River, South China

    International Nuclear Information System (INIS)

    Antibiotic susceptibility, detection of sul gene types and presence of class 1, 2 and 3 integrons and gene cassettes using PCR assays were investigated in 3456 Escherichia coli isolates obtained from 38 sampling sites of the Dongjiang River catchment in the dry and wet seasons. 89.1% of the isolates were resistant and 87.5% showed resistance to at least three antibiotics. sul2 was detected most frequently in 89.2% of 1403 SXT-resistant isolates. The presence of integrons (class 1 and 2) was frequently observed (82.3%) while no class 3 integron was found. In these integrons, 21 resistance genes of 14 gene cassette arrays and 10 different families of resistance genes were identified. Three gene cassette arrays, aac(6')-Ib-cr-aar-3-dfrA27-aadA16, aacA4-catB3-dfrA1 and aadA2-lnuF, were detected for the first time in surface water. The results showed that bacterial resistance in the catchment was seriously influenced by human activities, especially discharge of wastewater. Highlights: ► Antibiotic resistance was investigated for a river catchment of southern China. ► 87.5% of E coli isolates showed resistance to at least three antibiotics. ► The presence of integrons (class 1 and 2) was frequently observed (82.3%). ► Bacterial resistance in the catchment was seriously influenced by human activities. - Bacterial resistance to antibiotics in a catchment is related to the discharge of wastewater into the aquatic environment.

  6. Proteomics for Drug Resistance on the Food Chain? Multidrug-Resistant Escherichia coli Proteomes from Slaughtered Pigs.

    Science.gov (United States)

    Ramos, Sónia; Silva, Nuno; Hébraud, Michel; Santos, Hugo M; Nunes-Miranda, Júlio Dinis; Pinto, Luís; Pereira, José E; Capelo, José-Luis; Poeta, Patrícia; Igrejas, Gilberto

    2016-06-01

    Understanding global drug resistance demands an integrated vision, focusing on both human and veterinary medicine. Omics technologies offer new vistas to decipher mechanisms of drug resistance in the food chain. For example, Escherichia coli resistance to major antibiotics is increasing whereas multidrug resistance (MDR) strains are now commonly found in humans and animals. Little is known about the structural and metabolic changes in the cell that trigger resistance to antimicrobial agents. Proteomics is an emerging field that is used to advance our knowledge in global health and drug resistance in the food chain. In the present proteomic analysis, we offer an overview of the global protein expression of different MDR E. coli strains from fecal samples of pigs slaughtered for human consumption. A full proteomic survey of the drug-resistant strains SU60, SU62, SU76, and SU23, under normal growth conditions, was made by two-dimensional electrophoresis, identifying proteins by MALDI-TOF/MS. The proteomes of these four E. coli strains with different genetic profiles were compared in detail. Identical transport, stress response, or metabolic proteins were discovered in the four strains. Several of the identified proteins are essential in bacterial pathogenesis (GAPDH, LuxS, FKBPs), development of bacterial resistance (Omp's, TolC, GroEL, ClpB, or SOD), and potential antibacterial targets (FBPA, FabB, ACC's, or Fab1). Effective therapies against resistant bacteria are crucial and, to accomplish this, a comprehensive understanding of putative resistance mechanisms is essential. Moving forward, we suggest that multi-omics research will further improve our knowledge about bacterial growth and virulence on the food chain, especially under antibiotic stress. PMID:27310477

  7. Antimicrobial resistance in equine faecal Escherichia coli isolates from North West England

    Directory of Open Access Journals (Sweden)

    Williams Nicola J

    2010-04-01

    Full Text Available Abstract Background Escherichia coli isolates of equine faecal origin were investigated for antibiotic resistance, resistance genes and their ability to perform horizontal transfer. Methods In total, 264 faecal samples were collected from 138 horses in hospital and community livery premises in northwest England, yielding 296 resistant E. coli isolates. Isolates were tested for susceptibility to antimicrobial drugs by disc diffusion and agar dilution methods in order to determine minimum inhibitory concentrations (MIC. PCR amplification was used to detect genes conferring resistance to: ampicillin (TEM and SHV beta-lactamase, chloramphenicol (catI, catII, catIII and cml, tetracycline (tetA, tetB, tetC, tetD, tet E and tetG, and trimethoprim (dfrA1, dfrA9, dfrA12, dfrA13, dfr7, and dfr17. Results The proportion of antibiotic resistant isolates, and multidrug resistant isolates (MDR was significantly higher in hospital samples compared to livery samples (MDR: 48% of hospital isolates; 12% of livery isolates, p dfr, TEM beta-lactamase, tet and cat, conferring resistance to trimethoprim, ampicillin, tetracycline and chloramphenicol, respectively. Within each antimicrobial resistance group, these genes occurred at frequencies of 93% (260/279, 91%, 86.8% and 73.5%, respectively; with 115/296 (38.8% found to be MDR isolates. Conjugation experiments were performed on selected isolates and MDR phenotypes were readily transferred. Conclusions Our findings demonstrate that E. coli of equine faecal origin are commonly resistant to antibiotics used in human and veterinary medicine. Furthermore, our results suggest that most antibiotic resistance observed in equine E. coli is encoded by well-known and well-characterized resistant genes common to E. coli from man and domestic animals. These data support the ongoing concern about antimicrobial resistance, MDR, antimicrobial use in veterinary medicine and the zoonotic risk that horses could potentially pose to

  8. A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011-2014)

    OpenAIRE

    Hanon, Jean-Baptiste; Jaspers, Stijn; Butaye, Patrick; Wattiau, Pierre; Méroc, Estelle; Aerts, Marc; Imberechts, Hein; Vermeersch, Katie; Van der Stede, Yves

    2015-01-01

    A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011-2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin...

  9. Association of AcrAB-tolC efflux pump and marA-soxS-rob regulon with ciprofloxacin-resistance in Shigella flexneri isolates%AcrAB-tolC外排泵及marA-soxS-rob调控系统对福氏志贺菌环丙沙星耐药性的影响

    Institute of Scientific and Technical Information of China (English)

    程玉谦; 杨贤; 祁伟

    2015-01-01

    Objective To investigate the association of AcrAB-tolC efflux pump and marA-soxS-rob regulon with ciprofloxacin-resistance in Shigella flexneri isolates.Methods Forty five strains of Shigella flexneri were isolated in stool samples collected from outpatient diarrhea clinics in Tianjin from 2009 to 2013.The antimicrobial susceptibility of bacteria was analyzed by Kirby-Bauer disk diffusion method.Ten ciprofloxacin-resistant Shigella flexneri isolates and 10 ciprofloxacin-sensitive isolates were randomly selected.The gyrA and parC genes,plasmid mediated quinolone resistant (PMQR) determinants,efflux pump genes (acrA,acrB) and regulation genes (marA,soxS,rob) were screened and sequenced.Minimum inhibition concentrations (MICs) of the strains were determined before and after efflux pump inhibitor carbonyl cyanide m-chlorophenylhydrazone (CCCP) was added.The expression of acrA,acrB,marA,soxS and rob genes in ciprofloxacin-resistant and ciprofloxacin-sensitive strains was detected by realtime fluorescence quantitative RCR (RT-PCR),and the differences of expression were evaluated using t test.Results Both gyrA and parC mutations were detected in all ciprofloxacin-resistant strains; qnrS1 was positive in ciprofloxacin-resistant strain CR2 and aac(6')-Ib-cr was positive in ciprofloxacin-resistant strain CR5.Efflux pump genes and regulation genes were not detected in ciprofloxacin-sensitive strains,while soxRS mutation was detected in all ciprofloxacin-resistant strains except CR10.MICs of quinolones in ciprofloxacin-resistant strains decreased to one-fourth or one-eighth when CCCP added,while not changed or only decreased to one-half in ciprofloxacin-sensitive strains.Expressions of acrA,acrB,marA and soxS were significantly higher in ciprofloxacin-resistant strains than those in ciprofloxacin-sensitive strains (P < 0.05 or P < 0.01).Conclusion Efflux pump may involve in the high-level ciprofloxacin resistance in Shigella flexneri through activating transcription of

  10. Clonal spread of antimicrobial-resistant Escherichia coli isolates among pups in two kennels

    Directory of Open Access Journals (Sweden)

    Takahashi Toshio

    2011-02-01

    Full Text Available Abstract Although the dog breeding industry is common in many countries, the presence of antimicrobial resistant bacteria among pups in kennels has been infrequently investigated. This study was conducted to better understand the epidemiology of antimicrobial-resistant Escherichia coli isolates from kennel pups not treated with antimicrobials. We investigated susceptibilities to 11 antimicrobials, and prevalence of extended-spectrum β-lactamase (ESBL in 86 faecal E. coli isolates from 43 pups in two kennels. Genetic relatedness among all isolates was assessed using pulsed-field gel electrophoresis (PFGE. Susceptibility tests revealed that 76% of the isolates were resistant to one or more of tested antimicrobials, with resistance to dihydrostreptomycin most frequently encountered (66.3% followed by ampicillin (60.5%, trimethoprim-sulfamethoxazole (41.9%, oxytetracycline (26.7%, and chloramphenicol (26.7%. Multidrug resistance, defined as resistance against two or more classes of antimicrobials, was observed in 52 (60.5% isolates. Three pups in one kennel harboured SHV-12 ESBL-producing isolates. A comparison between the two kennels showed that frequencies of resistance against seven antimicrobials and the variation in resistant phenotypes differed significantly. Analysis by PFGE revealed that clone sharing rates among pups of the same litters were not significantly different in both kennels (64.0% vs. 88.9%, whereas the rates among pups from different litters were significantly different between the two kennels (72.0% vs. 33.3%, P E. coli clones, including multidrug-resistant and ESBL-producing clones. It is likely that resistant and susceptible bacteria can clonally spread among the same and/or different litters thus affecting the resistance prevalence.

  11. The in vitro fitness cost of antimicrobial resistance in Escherichia coli varies with the growth conditions

    DEFF Research Database (Denmark)

    Petersen, Andreas; Aarestrup, Frank Møller; Olsen, John Elmerdahl

    2009-01-01

    significantly when the bacteria were grown under all stress conditions tested, while the cost in 1/3 Luria–Bertani was not significantly changed in a streptomycin+rifampicin mutant. The increase in the fitness cost depended in a nonregular manner on the strain/stress combination. The fitness cost of plasmid....... However, the growth potential of bacteria with antimicrobial resistances did not increase in a straightforward manner in these in vitro experiments and is therefore probably even more difficult to predict in vivo.......The objective of this study was to investigate the influence of stressful growth conditions on the fitness cost of antimicrobial resistance in Escherichia coli BJ4 caused by chromosomal mutations and plasmid acquisition. The fitness cost of chromosomal streptomycin resistance increased...

  12. Toll-like receptors recognize distinct proteinase-resistant glycoconjugates in Campylobacter jejuni and Escherichia coli.

    Science.gov (United States)

    Phongsisay, Vongsavanh; Hara, Hiromitsu; Fujimoto, Shuji

    2015-03-01

    Campylobacter jejuni causes gastroenteritis and autoimmune neuropathy Guillain-Barré syndrome. The mechanism by which C. jejuni infection results in such the hyperimmunity is not completely understood. Host immunity plays an important role in the disease pathogenesis; however, little is known how immune system recognizes this human pathogen. In this study, we report that Toll-like receptors recognize distinct proteinase K-resistant glycoconjugates in C. jejuni and Escherichia coli. Lipopolysaccharide is solely proteinase-resistant glycoconjugate in E. coli. In contrast, C. jejuni possesses at least five different components that are resistant to proteinase digestion and are capable of inducing NF-κB activation through TLR2 and TLR4. Possession of multiple activators of Toll-like receptors may be the unique strategy of C. jejuni to trigger hyperimmunity.

  13. Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.; Bisbal, M.; Arias, W.; Baerga, C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Dept. of Biology; Hazen, T.C. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.

    1988-12-31

    High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. The high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.

  14. Investigation into the resistance of lactoperoxidase tolerant Escherichia coli mutants to different forms of oxidative stress.

    Science.gov (United States)

    De Spiegeleer, Philipp; Vanoirbeek, Kristof; Lietaert, Annelies; Sermon, Jan; Aertsen, Abram; Michiels, Chris W

    2005-11-15

    Six lactoperoxidase tolerant Escherichia coli transposon mutants isolated and characterized in an earlier study, and some newly constructed double mutants, were subjected to peroxide, superoxide and hypochlorite stress, and their inactivation was compared to that of the wild type strain MG1655. Knock out mutants of waaQ and waaO, which owed their lactoperoxidase tolerance to an impaired outer membrane permeability due to a reduced porin content, also exhibited higher resistance to hypochlorite, as did a knock-out strain of lrp, encoding a regulatory protein affecting a wide range of cellular functions. Unlike the outer membrane mutants however, the lrp strain was also more resistant to t-butyl hydroperoxide, but more susceptible to the superoxide generating compound plumbagin. Finally, a lactoperoxidase tolerant knock-out strain of ulaA, involved in ascorbic acid uptake, did not show resistance to any of the other oxidants. The possible modes of action of these different oxidants are discussed.

  15. Prevalence and characterization of antimicrobial-resistant Escherichia coli isolated from conventional and organic vegetables.

    Science.gov (United States)

    Kim, Sara; Woo, Gun-Jo

    2014-10-01

    To compare the characteristics and to identify the epidemiological relationships of Escherichia coli isolated from organic and conventional vegetables, the antimicrobial resistance and genetic properties of E. coli were investigated from 2010 to 2011. E. coli was isolated from 1 of 111 (0.9%) organic vegetables and from 20 of 225 (8.9%) conventional vegetables. The majority of strains were isolated from the surrounding farming environment (n=27/150 vs. 49/97 in organic vs. conventional samples). The majority of the vegetable strains were isolated from the surrounding farming environments. E. coli isolated from organic vegetables showed very low antimicrobial resistance rates except for cephalothin, ranging from 0% to 17.9%, while the resistance rates to cephalothin (71%) were extremely high in both groups. E. coli isolates expressed various resistance genes, which most commonly included blaTEM, tet(A), strA, strB, and qnrS. However, none of the isolates harbored tet(D), tet(E), tet(K), tet(L), tet(M), or qnrA. The transferability of tet gene, tet(A), and tet(B) was identified in tetracycline-resistant E. coli, and the genetic relationship was confirmed in a few cases from different sources. With regard to the lower antimicrobial resistance found in organic produce, this production mode seems able to considerably reduce the selection of antimicrobial-resistant bacteria on vegetables. PMID:25140978

  16. Microarray Evaluation of Antimicrobial Resistance and Virulence of Escherichia coli Isolates from Portuguese Poultry

    Directory of Open Access Journals (Sweden)

    Nuno Mendonça

    2016-01-01

    Full Text Available The presence of antimicrobial resistance and virulence factors of 174 Escherichia coli strains isolated from healthy Portuguese Gallus gallus was evaluated. Resistance profiles were determined against 33 antimicrobials by microbroth dilution. Resistance was prevalent for tetracycline (70% and ampicillin (63%. Extended-spectrum beta-lactamase (ESBL phenotype was observed in 18% of the isolates. Multidrug resistance was found in 56% of isolates. A subset of 74 isolates were screened by DNA microarrays for the carriage of 88 antibiotic resistance genes and 62 virulence genes. Overall, 37 different resistance genes were detected. The most common were tet(A (72%, blaTEM (68%, and sul1 (47%, while 21% isolates harbored an ESBL gene (blaCTX-M group 1, group 2, or group 9. Of these, 96% carried the increased serum survival (iss virulence gene, while 89% presented the enterobactin siderophore receptor protein (iroN, 70% the temperature-sensitive hemagglutinin (tsh, and 68% the long polar fimbriae (lpfA virulence genes associated with extraintestinal pathogenic E. coli. In conclusion, prevalence of antibiotic resistant E. coli from the microbiota of Portuguese chickens was high, including to extended spectrum cephalosporins. The majority of isolates seems to have the potential to trigger extraintestinal human infection due to the presence of some virulence genes. However, the absence of genes specific for enteropathogenic E. coli reduces the risk for human intestinal infection.

  17. Complete Genome Sequences of Escherichia coli O157:H7 Strains SRCC 1675 and 28RC, Which Vary in Acid Resistance

    Science.gov (United States)

    Baranzoni, Gian Marco; Reichenberger, Erin R.; Kim, Gwang-Hee; Breidt, Frederick; Kay, Kathryn; Oh, Deog-Hwan

    2016-01-01

    The level of acid resistance among Escherichia coli O157:H7 strains varies, and strains with higher resistance to acid may have a lower infectious dose. The complete genome sequences belonging to two strains of Escherichia coli O157:H7 with different levels of acid resistance are presented here. PMID:27469964

  18. Complete genome sequences of Escherichia coli O157:H7 strains SRCC 1675 and 28RC that vary in acid resistance

    Science.gov (United States)

    The level of acid resistance among Escherichia coli O157:H7 strains varies, and strains with higher resistance to acid may have a lower infectious dose. The complete genome sequences belonging to two strains of Escherichia coli O157:H7 with different levels of acid resistance are presented....

  19. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    OpenAIRE

    F Amin Harati; Amini, M; AR Shahverdi; Pourmand MR; Yousefi, M

    2012-01-01

    Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has inc...

  20. Efficient Recovery of Fluoroquinolone-Susceptible and Fluoroquinolone-Resistant Escherichia coli Strains From Frozen Samples

    Science.gov (United States)

    Lautenbach, Ebbing; Santana, Evelyn; Lee, Abby; Tolomeo, Pam; Black, Nicole; Babson, Andrew; Perencevich, Eli N.; Harris, Anthony D.; Smith, Catherine A.; Maslow, Joel

    2010-01-01

    We assessed the rate of recovery of fluoroquinolone-resistant and fluoroquinolone-susceptible Escherichia coli isolates from culture of frozen perirectal swab samples compared with the results for culture of the same specimen before freezing. Recovery rates for these 2 classes of E. coli were 91% and 83%, respectively. The majority of distinct strains recovered from the initial sample were also recovered from the frozen sample. The strains that were not recovered were typically present only in low numbers in the initial sample. These findings emphasize the utility of frozen surveillance samples. PMID:18279070

  1. Distribution of phylogroups and co-resistance to antimicrobial agents in ampicillin resistant Escherichia coli isolated from healthy humans and from patients with bacteraemia

    DEFF Research Database (Denmark)

    Haugaard, A.; Hammerum, A. M.; Porsbo, Lone Jannok;

    In 2002-03, 31 ampicillin resistant faecal isolates were collected from healthy humans. Moreover, 31 ampicillin resistant blood isolates from patients with bacte-raemia were collected in 2000-02. All isolates were tested positive for the pres-ence of blaTEM. Isolates were characterized by minimum...... inhibitory concentration to antimicrobial agents and examined by PCR to determine their phylogroups. The phylotyping grouped the faecal samples into A (13%), B1 (10%), B2 (42%), D (19%), NT (16%) while the blood isolates grouped into A (16%), B1 (0%), B2 (48%), D (32%) and NT (3%). The frequency...... of resistance in faecal and blood isolates (F/B) was: tetracycline (48%/48%), gentamicin (0%/10%), ciprofloxacin (3%,13%), sulfonamide (68%/77%) and trimethoprim (39%/39%). Conclusion: B2 was the most prevalent phylogroup found both in faecal isolates collected from healthy humans and in blood isolates from...

  2. Virulence factors and drug resistance in Escherichia coli isolated from extraintestinal infections

    Directory of Open Access Journals (Sweden)

    Sharma S

    2007-01-01

    Full Text Available Purpose: To determine the virulence factors produced by Escherichia coli isolated from extraintestinal infections, to study the drug resistance pattern in E. coli with special reference to extended spectrum β -lactamase (ESBL and to evaluate screening methods for ESBL. Methods: A total of 152 isolates of E. coli from various extraintestinal infections were screened for virulence factors such as haemolysin, surface hydrophobicity, serum resistance and protease. All the isolates were also studied for antibiotic susceptibility pattern using modified Kirby Bauer disk diffusion method. ESBL production was screened by standard disk diffusion method and confirmed using phenotypic confirmatory method. Results: Among 152 isolates, 36 (23.7% were haemolytic, 42 (27.6% were hydrophobic, 132 (86.8% were serum resistant and only four were positive for protease. Multiple virulence factor were observed in 67 (44% of isolates. Seventy-nine (51.4% isolates produced ESBL. ESBL producing isolates showed multidrug resistance. There was a significant association ( P < 0.001 between multiple virulence factors and ESBL production by extraintestinal E. coli . Conclusions: The present study shows the expression of virulence factors and multidrug resistance in E. coli isolated from various extraintestinal infections. The study also shows that appropriate methods of detecting drug resistance and ESBL production are required for the judicious use of antibiotics in managing these infections.

  3. Antibiotic resistance and integrons in Shiga toxin-producing Escherichia coli (STEC

    Directory of Open Access Journals (Sweden)

    Rocío Colello

    2015-03-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC cause hemorrhagic colitis (HC and hemolytic-uremic syndrome in humans (HUS. Cattle are the main reservoir of STEC and transmission to humans occurs through contaminated food and water. Antibiotics are used in pig production systems to combat disease and improve productivity and play a key role in the dissemination of antibiotic resistance genes to the bacteria. Integrons have been identified in resistant bacteria allowing for the acquisition and dissemination of antibiotic resistance genes. STEC strains isolated from humans and animals have developed antibiotic resistance. In our laboratory, 21 non-157 STEC strains isolated from pigs were analyzed to detect class 1 and 2 integrons by PCR. Eight carried integrons, 7 of them harbored intl2. In another study 545 STEC strains were also analyzed for the presence of intl1 and intl2. Strains carrying intl1 belonged to isolates from environment (n = 1, chicken hamburger (n = 2, dairy calves (n = 4 and pigs (n = 8. Two strains isolated from pigs harbored intl2 and only one intl1/intl2, highlighting the presence of intl2 in pigs. The selection for multiresistant strains may contribute to the emergence of antibiotic resistant pathogens and facilitate the spreading of the mobile resistance elements to other bacteria.

  4. Antibiotic resistance in uropathogenic Escherichia coli isolated from urinary tract infections out-patients in Kermanshah

    Directory of Open Access Journals (Sweden)

    Somayeh Jalilian

    2014-01-01

    Full Text Available Background: Urinary tract infections (UTIs are common cause of infections described in out-patient's setting and increase in antibiotic resistance of Escherichia coli, is encountered world-wide. Antibiotic treatment is usually empirical; therefore, this study to provide the knowledge of local resistance pathogen patterns in Kermanshah. Materials and Methods: We conducted a retrospective analysis of all E. coli isolates from urine samples admitted to Kermanshah Central lab between March 2011 and 2012 were included. Antimicrobial resistance was tested by the Kirby-Bauer disk diffusion. Results: This study showed a total of 20,742 samples, 1228 (5.92 were positive for pathogenic bacteria. E. coli were the predominant 801 isolate (65.2%. Out of the 13 antibiotics tested for E. coli isolates, minimum and maximum resistance were observed to ampicillin (9.4% and augmentin (68.6%. Almost 59-66% of the uropathogenic E. coli strains were resistant to amikacin, co-trimoxazole, tetracycline and cephalotin and nearly half of them were resistant to nalidixic acid and cephalexin. Conclusion: This study confirms that E. coli is still the most common uropathogen isolated. Augmentin and amikacin are not as a first choice for treatment of UTI in Kermanshah area. Ampicillin and nitrofurantoin may be considered as a first choice empiric agent in out-patients.

  5. Chloramphenicol- and tetracycline-resistant uropathogenic Escherichia coli (UPEC) exhibit reduced virulence potential.

    Science.gov (United States)

    Starcic Erjavec, Marjanca; Rijavec, Matija; Krizan-Hergouth, Veronika; Fruth, Angelika; Zgur-Bertok, Darja

    2007-11-01

    It is well documented that uropathogenic Escherichia coli (UPEC) isolates resistant to nalidixic acid have reduced virulence potential. Our goal was to assess whether UPEC isolates resistant to chloramphenicol, tetracycline and streptomycin also exhibit reduced virulence potential. Among 110 human UPEC isolates, the prevalences of the virulence factors fimH, papC, papGII, papGIII, sfa/focDE, afa, hlyA, cnf1, usp, ibeA, fyuA, iroN, iucD, ireA, and K1 and K5 capsules as well as of pathotypes, phylogenetic groups, O antigens and a pathogenicity island (PAI) marker were compared between chloramphenicol-, tetracycline-, streptomycin- and, as a control, nalidixic acid-resistant and -susceptible strains. Our findings show that among human UPEC isolates, not only nalidixic acid-resistant but also chloramphenicol- and tetracycline-resistant isolates have reduced virulence potential compared with susceptible strains. To our knowledge, this is the first report of a statistically significant reduction in virulence traits among chloramphenicol- and tetracycline-resistant isolates.

  6. Induction of bacterial antibiotic resistance by mutagenic halogenated nitrogenous disinfection byproducts.

    Science.gov (United States)

    Lv, Lu; Yu, Xin; Xu, Qian; Ye, Chengsong

    2015-10-01

    Halogenated nitrogenous disinfection byproducts (N-DBPs) raise concerns regarding their mutagenicity and carcinogenicity threatening public health. However, environmental consequence of their mutagenicity has received less attention. In this study, the effect of halogenated N-DBPs on bacterial antibiotic resistance (BAR) was investigated. After exposure to bromoacetamide (BAcAm), trichloroacetonitrile (TCAN) or tribromonitromethane (TBNM), the resistance of Pseudomonas aeruginosa PAO1 to both individual and multiple antibiotics (ciprofloxacin, gentamicin, polymyxin B, rifampin, tetracycline, ciprofloxacin + gentamicin and ciprofloxacin + tetracycline) was increased, which was predominantly ascribed to the overexpression of efflux pumps. The mechanism of this effect was demonstrated to be mutagenesis through sequencing and analyzing antibiotic resistance genes. The same induction phenomena also appeared in Escherichia coli, suggesting this effect may be universal to waterborne pathogens. Therefore, more attention should be given to halogenated N-DBPs, as they could increase not only genotoxicological risks but also epidemiological risks of drinking water.

  7. Prevalence and risk factor analysis of resistant Escherichia coli urinary tract infections in the emergency department.

    Directory of Open Access Journals (Sweden)

    Bailey AM

    2013-06-01

    Full Text Available Background: Escherichia coli (E. coli is a frequent uropathogen in urinary tract infections (UTI. Widespread resistance to sulfamethoxazole-trimethoprim (SMX-TMP and increasing resistance to fluoroquinolones amongst these isolates has been recognized. There are limited data demonstrating risk factors for resistance to both SMX-TMP and fluoroquinolones.Objectives: This study was conducted to assess for the prevalence of community resistance amongst E. coli isolates to SMX-TMP and levofloxacin in ambulatory patients discharged from the emergency department (ED.Methods: Adults presenting for evaluation and discharged from the ED with a diagnosis of an E. coli UTI were retrospectively reviewed. Utilizing demographic and clinical data the prevalence of E. coli resistance and risk factors associated with SMX-TMP- and fluoroquinolone-resistant infection were determined. Results: Among the 222 patients, the mean rates of E. coli susceptibility to levofloxacin and SMX-TMP were 82.4% and 72.5%, respectively. Significant risk factors for resistance to SMX-TMP included prior antibiotic use (p=0.04 and prior diagnosis of UTI (p= 0.01. Significant risk factors for resistance to levofloxacin included: male gender, age, presence of hypertension, diabetes, chronic respiratory disease, nursing home resident, previous antibiotic use, previous diagnosis of UTI, existence of renal or genitourinary abnormalities, and prior surgical procedures (p <0.05 for all comparisons. The number of hospital days prior to initial ED evaluation (p<0.001 was determined to be a predictive factor in hospital and ED readmission. Conclusions: These results suggest that conventional approaches to monitoring for patterns of susceptibility may be inadequate. It is imperative that practitioners develop novel approaches to identifying patients with risk factors for resistance. Identification of risk factors from this evaluation should prompt providers to scrutinize the use of these agents in

  8. Prevalence and Antimicrobial Resistance in Escherichia coli from Food Animals in Lagos, Nigeria.

    Science.gov (United States)

    Adenipekun, Eyitayo O; Jackson, Charlene R; Oluwadun, Afolabi; Iwalokun, Bamidele A; Frye, Jonathan G; Barrett, John B; Hiott, Lari M; Woodley, Tiffanie A

    2015-06-01

    Foodborne bacteria are often associated with human infections; these infections can become more complicated to treat if the bacteria are also resistant to antimicrobials. In this study, prevalence, antimicrobial resistance, and genetic relatedness of Escherichia coli among food producing animals from Lagos, Nigeria, was investigated. From December 2012 to June 2013, E. coli were isolated from fecal samples of healthy cattle, chicken, and swine. Antimicrobial susceptibility testing against 22 antimicrobials was performed using broth microdilution with the Sensititre™ system. Clonal types were determined by pulsed-field gel electrophoresis (PFGE). From the analysis, 211/238 (88.7%), 170/210 (81%), and 136/152 (89.5%) samples from cattle, chicken, and swine, respectively, were positive for E. coli. A subset of those isolates (n=211) selected based on β-lactamase production was chosen for further study. Overall, E. coli exhibited the highest resistance to tetracycline (124/211; 58.8%), trimethoprim/sulfamethoxazole (84/211; 39.8%), and ampicillin (72/211; 34.1%). Approximately 40% of the isolates were pan-susceptible, and none of the isolates were resistant to amikacin, cefepime, ceftazidime, ertapenem, meropenem, or tigecycline. Among the resistant isolates, 28 different resistance patterns were observed; 26 of those were characterized as multi-drug resistant (MDR; resistance to ≥2 antimicrobials). One isolate was resistant to 13 different antimicrobials representing five different antimicrobial classes. Using PFGE, MDR E. coli were genetically diverse and overall did not group based on source; identical PFGE patterns were detected among isolates from different sources. These results suggest that isolates cannot be attributed to specific sources, and some may be present across all of the sources. Results from this study indicate that food-producing animals in Nigeria are a reservoir of MDR E. coli that may be transferred to humans via the food chain. PMID

  9. Plasmid-Mediated OqxAB Is an Important Mechanism for Nitrofurantoin Resistance in Escherichia coli.

    Science.gov (United States)

    Ho, Pak-Leung; Ng, Ka-Ying; Lo, Wai-U; Law, Pierra Y; Lai, Eileen Ling-Yi; Wang, Ya; Chow, Kin-Hung

    2015-11-09

    Increasing consumption of nitrofurantoin (NIT) for treatment of acute uncomplicated urinary tract infections (UTI) highlights the need to monitor emerging NIT resistance mechanisms. This study investigated the molecular epidemiology of the multidrug-resistant efflux gene oqxAB and its contribution to nitrofurantoin resistance by using Escherichia coli isolates originating from patients with UTI (n = 205; collected in 2004 to 2013) and food-producing animals (n = 136; collected in 2012 to 2013) in Hong Kong. The oqxAB gene was highly prevalent among NIT-intermediate (11.5% to 45.5%) and -resistant (39.2% to 65.5%) isolates but rare (0% to 1.7%) among NIT-susceptible (NIT-S) isolates. In our isolates, the oqxAB gene was associated with IS26 and was carried by plasmids of diverse replicon types. Multilocus sequence typing revealed that the clones of oqxAB-positive E. coli were diverse. The combination of oqxAB and nfsA mutations was found to be sufficient for high-level NIT resistance. Curing of oqxAB-carrying plasmids from 20 NIT-intermediate/resistant UTI isolates markedly reduced the geometric mean MIC of NIT from 168.9 μg/ml to 34.3 μg/ml. In the plasmid-cured variants, 20% (1/5) of isolates with nfsA mutations were NIT-S, while 80% (12/15) of isolates without nfsA mutations were NIT-S (P = 0.015). The presence of plasmid-based oqxAB increased the mutation prevention concentration of NIT from 128 μg/ml to 256 μg/ml and facilitated the development of clinically important levels of nitrofurantoin resistance. In conclusion, plasmid-mediated oqxAB is an important nitrofurantoin resistance mechanism. There is a great need to monitor the dissemination of this transferable multidrug-resistant efflux pump.

  10. Surveillance and Detection of Inhibitor-Resistant Beta-Lactamases in Clinical Isolates of Escherichia coli

    Directory of Open Access Journals (Sweden)

    Carl Urban

    2007-06-01

    Full Text Available In recent years, resistance to beta-lactam antibiotics, such as the widely-used cephalosporins and penicillins, has become a major challenge for disease therapy, particularly in common hospital-acquired infections. In the search for the mechanisms behind this increasingly prevalent form of resistance, microbiologists have identified a new type of beta-lactamase enzyme, called inhibitor-resistant TEMs (IRTs, which can withstand the effects of beta-lactamase inhibitor compounds, further reducing the arsenal of drugs available to physicians facing resistant bacteria. In this study, we examined the enzymatic and genetic basis of Escherichia coli isolates demonstrating such resistance to beta-lactam/beta-lactamase inhibitor combinations. Susceptibility trials played a major role in composing the experimental cohort for this project (n=50; each isolate was thoroughly tested to ensure that it was resistant to ampicillin-sulbactam, an inhibitor combination, but susceptible to the third-generation cephalosporin ceftazidime. Subsequently, a number of samples were subjected to assay by pulsed-field gel electrophoresis (n=18 and polymerase chain reaction (n=3 so that their genetic composition and relatedness might be known. In particular, the presence of genes coding for TEM-type beta-lactamases was investigated for each of the 3 isolates sequenced. Even though it was anticipated that the isolates would possess resistance to inhibitor combinations due to an IRT gene, this was not found to be the case. Instead, the mechanism of resistance turned out to be over-expression of a gene coding for a normal TEM enzyme. The results of these experiments have implications for ensuring successful therapy of bacterial infections and for preventing the spread of antimicrobial resistance.

  11. Comparison of Disk Diffusion and Agar Dilution Methods for Erythromycin and Ciprofloxacin Susceptibility Testing of Campylobacter jejuni subsp. jejuni▿

    OpenAIRE

    Gaudreau, Christiane; Girouard, Yves; Ringuette, Louise; Tsimiklis, Catherine

    2007-01-01

    Disk diffusion was a reliable, easy, and inexpensive method for testing the susceptibility of Campylobacter jejuni to erythromycin (215 susceptible and 45 resistant isolates) and to ciprofloxacin (154 susceptible, two intermediate, and 124 resistant isolates) using, respectively, an erythromycin disk and ciprofloxacin and nalidixic acid disks.

  12. Compound list: ciprofloxacin [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available ciprofloxacin CPX 00050 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/ciprofloxacin....Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vitro/ciprofloxacin...edbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/ciprofloxacin.Rat.in_vivo.Liver.Repeat.zip ftp:...//ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Kidney/Single/ciprofloxacin.Rat.in_vivo.Kidne...y.Single.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Kidney/Repeat/ciprofloxacin.Rat.in_vivo.Kidney.Repeat.zip ...

  13. Ciprofloxacin susceptibility of Pseudomonas aeruginosa isolates from keratitis

    DEFF Research Database (Denmark)

    Lomholt, JA; Kilian, Mogens

    2003-01-01

    AIM: To examine the ciprofloxacin susceptibility of 106 Pseudomonas aeruginosa eye isolates from the United Kingdom, Denmark, India, the United States, and Australia, and to determine the molecular mechanisms of resistance. METHODS: Ciprofloxacin susceptibility was tested by an agar dilution method...... of 90 keratitis isolates (3.3%), one from the United Kingdom and two from India, exhibited MIC values of 16 mg/l or 32 mg/l. The UK isolate had a mutation in gyrA (Thr83Ile), whereas the two Indian isolates showed mutations in both gyrA (Thr83Ile) and parC (Ser87Leu). The remaining isolates from...

  14. Heterogeneous catalytic ozonation of ciprofloxacin in water with carbon nanotube supported manganese oxides as catalyst

    International Nuclear Information System (INIS)

    Highlights: ► Ciprofloxacin in water was degraded by heterogeneous catalytic ozonation. ► MnOx were supported on MWCNTs to serve as catalyst for ozonation. ► MnOx/MWCNT exhibited highly catalytic activity on ozonation of ciprofloxacin in water. ► MnOx/MWCNT resulted in effective antibacterial activity inhibition on ciprofloxacin. ► MnOx/MWCNT promoted the generation of hydroxyl radicals. - Abstract: Carbon nanotube-supported manganese oxides (MnOx/MWCNT) were used as catalysts to assist ozone in degrading ciprofloxacin in water. Manganese oxides were successfully loaded on multi-walled carbon nanotube surfaces by simply impregnating the carbon nanotube with permanganate solution. The catalytic activities of MnOx/MWCNT in ciprofloxacin ozonation, including degradation, mineralization effectiveness, and antibacterial activity change, were investigated. The presence of MnOx/MWCNT significantly elevated the degradation and mineralization efficiency of ozone on ciprofloxacin. The microbiological assay with a reference Escherichia coli strain indicated that ozonation with MnOx/MWCNT results in more effective antibacterial activity inhibition of ciprofloxacin than that in ozonation alone. The effects of catalyst dose, initial ciprofloxacin concentration, and initial pH conditions on ciprofloxacin ozonation with MnOx/MWCNT were surveyed. Electron spin resonance trapping was applied to assess the role of MnOx/MWCNT in generating hydroxyl radicals (HO·) during ozonation. Stronger 5,5-dimethyl-1-pyrroline-N-oxide–OH signals were observed in the ozonation with MnOx/MWCNT compared with those in ozonation alone, indicating that MnOx/MWCNT promoted the generation of hydroxyl radicals. The degradation of ciprofloxacin was studied in drinking water and wastewater process samples to gauge the potential effects of water background matrix on MnOx/MWCNT catalytic ozonation.

  15. Heterogeneous catalytic ozonation of ciprofloxacin in water with carbon nanotube supported manganese oxides as catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Minghao, E-mail: suiminghao.sui@gmail.com [State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Xing, Sichu; Sheng, Li; Huang, Shuhang; Guo, Hongguang [State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Ciprofloxacin in water was degraded by heterogeneous catalytic ozonation. Black-Right-Pointing-Pointer MnOx were supported on MWCNTs to serve as catalyst for ozonation. Black-Right-Pointing-Pointer MnOx/MWCNT exhibited highly catalytic activity on ozonation of ciprofloxacin in water. Black-Right-Pointing-Pointer MnOx/MWCNT resulted in effective antibacterial activity inhibition on ciprofloxacin. Black-Right-Pointing-Pointer MnOx/MWCNT promoted the generation of hydroxyl radicals. - Abstract: Carbon nanotube-supported manganese oxides (MnOx/MWCNT) were used as catalysts to assist ozone in degrading ciprofloxacin in water. Manganese oxides were successfully loaded on multi-walled carbon nanotube surfaces by simply impregnating the carbon nanotube with permanganate solution. The catalytic activities of MnOx/MWCNT in ciprofloxacin ozonation, including degradation, mineralization effectiveness, and antibacterial activity change, were investigated. The presence of MnOx/MWCNT significantly elevated the degradation and mineralization efficiency of ozone on ciprofloxacin. The microbiological assay with a reference Escherichia coli strain indicated that ozonation with MnOx/MWCNT results in more effective antibacterial activity inhibition of ciprofloxacin than that in ozonation alone. The effects of catalyst dose, initial ciprofloxacin concentration, and initial pH conditions on ciprofloxacin ozonation with MnOx/MWCNT were surveyed. Electron spin resonance trapping was applied to assess the role of MnOx/MWCNT in generating hydroxyl radicals (HO{center_dot}) during ozonation. Stronger 5,5-dimethyl-1-pyrroline-N-oxide-OH signals were observed in the ozonation with MnOx/MWCNT compared with those in ozonation alone, indicating that MnOx/MWCNT promoted the generation of hydroxyl radicals. The degradation of ciprofloxacin was studied in drinking water and wastewater process samples to gauge the potential effects of water background matrix on

  16. Diversity of Plasmids and Antimicrobial Resistance Genes in Multidrug-Resistant Escherichia coli Isolated from Healthy Companion Animals.

    Science.gov (United States)

    Jackson, C R; Davis, J A; Frye, J G; Barrett, J B; Hiott, L M

    2015-09-01

    The presence and transfer of antimicrobial resistance genes from commensal bacteria in companion animals to more pathogenic bacteria may contribute to dissemination of antimicrobial resistance. The purpose of this study was to determine antimicrobial resistance gene content and the presence of genetic elements in antimicrobial resistant Escherichia coli from healthy companion animals. In our previous study, from May to August, 2007, healthy companion animals (155 dogs and 121 cats) from three veterinary clinics in the Athens, GA, USA area were sampled and multidrug-resistant E. coli (n = 36; MDR, resistance to ≥ 2 antimicrobial classes) were obtained. Of the 25 different plasmid replicon types tested by PCR, at least one plasmid replicon type was detected in 94% (34/36) of the MDR E. coli; four isolates contained as many as five different plasmid replicons. Nine replicon types (FIA, FIB, FII, I2, A/C, U, P, I1 and HI2) were identified with FIB, FII, I2 as the most common pattern. The presence of class I integrons (intI) was detected in 61% (22/36) of the isolates with eight isolates containing aminoglycoside- and/or trimethoprim-resistance genes in the variable cassette region of intI. Microarray analysis of a subset of the MDR E. coli (n = 9) identified the presence of genes conferring resistance to aminoglycosides (aac, aad, aph and strA/B), β-lactams (ampC, cmy, tem and vim), chloramphenicol (cat), sulfonamides (sulI and sulII), tetracycline [tet(A), tet(B), tet(C), tet(D) and regulator, tetR] and trimethoprim (dfrA). Antimicrobial resistance to eight antimicrobials (ampicillin, cefoxitin, ceftiofur, amoxicillin/clavulanic acid, streptomycin, gentamicin, sulfisoxazole and trimethoprim-sulfamethoxazole) and five plasmid replicons (FIA, FIB, FII, I1 and I2) were transferred via conjugation. The presence of antimicrobial resistance genes, intI and transferable plasmid replicons indicate that E. coli from companion animals may play an important role in the

  17. "Population structure of drug-susceptible,-resistant and ESBL-producing Escherichia coli from community-acquired urinary tract"

    DEFF Research Database (Denmark)

    Hertz, Frederik Boëtius; Nielsen, Jesper Boye; Schønning, Kristian;

    2016-01-01

    BACKGROUND: Escherichia coli is the most common cause of urinary tract infection (UTI). The pathogenic isolates are becoming increasingly resistant to antibiotics; with a worldwide dissemination of resistant sequence types (ST). We characterized three different uropathogenic E. coli populations, ...... population was a much more diverse group than the resistant and ESBL-producing E. coli populations. Overall, these findings suggest that dominant ESBL-producing lineages are derived from UPEC lineages already established in the general UPEC population....

  18. 氟喹诺酮类药物体外诱导大肠埃希菌耐药性观察%Observation of Escherichia coli induced resistance to fluoroquinolones in vitro

    Institute of Scientific and Technical Information of China (English)

    赵磊; 荆鹏伟

    2011-01-01

    Aim: To observe the induced resistance of Escherichia coli to a variety of fluoroquinolones in drug concentration of sub-M/C. Methods-.The experiments on induced resistance to ciprofloxacin.levofloxacin or gatifloxacin were performed, in thrity-two Escherichia coli sensitived to fluoroquinolones from clinic,respectively, by multiple-step method. The susceptibility of the induced strains resistant to fluoroquinolones was measured by determining the MIC using agar dilution method. Results:The strains highly resistant to fluoroquinolone were obtained from 22 tested strain of Escherichia coli,the MICs of these laboratory resistant strains were with 32 to 3 000 fold increase, respectively, when compared with parent strains. All six induced highly resistant strains examined carried two gyrA mutations affecting residues 83Ser→Leu,Asp87→ Asn and one parC mutation of 80Ser→Ile. No mutation was found in a susceptible isolate. Conclusion :Acquired resistance could be occurred when exposing to low level of some fluoroquinolones for long term.%目的:探讨大肠埃希菌在氟喹若酮类最低抑菌浓度(MIC)下耐药性的产生,以指导临床合理使用抗生素.方法:采用多步诱导法,对32株临床分离的氟喹诺酮类敏感大肠埃希菌分别进行环丙沙星、左氧氟沙星和加替沙星的诱导性耐药试验;用琼脂稀释法测定诱导前后敏感菌株的药物敏感性;用PCR方法测定耐药基因序列.结果:22株大肠埃希菌诱导出稳定的高耐氟喹诺酮菌株;与原株比较,耐药株的MIC分别增加了32~3 000倍;进行测序的6株诱导耐药菌株均发生gyrA的83Ser→Leu、87Asp→Ash和parc的80Ser→Ile突变,而测序的1株敏感菌株未发现基因突变.结论:在低浓度抗菌药物的长期压力下,可诱导大肠埃希菌产生对氟喹诺酮类的获得性耐药.

  19. Induction of Antimicrobial Resistance in Escherichia coli and Non-Typhoidal Salmonella Strains after Adaptation to Disinfectant Commonly Used on Farms in Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen T. Nhung

    2015-10-01

    Full Text Available In Vietnam, commercial disinfectants containing quaternary ammonium compounds (QACs are commonly used in pig and poultry farms to maintain hygiene during production. We hypothesized that sustained exposure to sub-bactericidal concentrations of QAC-based disinfectants may result in increased levels of antimicrobial resistance (AMR among Enterobacteriacea due to the increase of efflux pump expression. To test this hypothesis we exposed six antimicrobial-susceptible Escherichia coli (E. coli and six antimicrobial-susceptible non-typhoidal Salmonella (NTS isolates to increasing concentrations of a commonly used commercial disinfectant containing a mix of benzalkonium chloride and glutaraldehyde. Over the 12-day experiment, strains exhibited a significant change in their minimum inhibitory concentration (MIC of the disinfectant product (mean increase of 31% (SD ± 40 (p = 0.02, paired Wilcoxon test. Increases in MIC for the disinfectant product were strongly correlated with increases in MIC (or decreases in inhibition zone for all antimicrobials (Pearson’s correlation coefficient 0.71–0.83, all p < 0.01. The greatest increases in MIC (or decreases in inhibition zone were observed for ampicillin, tetracycline, ciprofloxacin, and chloramphenicol, and the smallest for gentamicin, trimethoprim/sulphamethoxazole. The treatment of 155 representative E. coli isolates from farmed and wild animals in the Mekong Delta (Vietnam with phenyl-arginine beta-naphthylamide (PAβN, a generic efflux pump inhibitor, resulted in reductions in the prevalence of AMR ranging from 0.7% to 3.3% in these organisms, indicating a small contribution of efflux pumps on the observed prevalence of AMR on farms. These results suggest that the mass usage of commercial disinfectants, many of which contain QACs, is potentially a contributing factor on the generation and maintenance of AMR in animal production in Vietnam.

  20. High-level Multi-Resistant and Virulent Escherichia coli in Abeokuta, Nigeria.

    Science.gov (United States)

    Akinduti, Paul Akinniyi; Aboderin, Bukola W; Oloyede, Rasaq; Ogiogwa, Joseph I; Motayo, Babatunde O; Ejilude, Oluwaseun

    2016-01-01

    Multi-resistant Escherichia coli (E. coli) strains co-harboring virulence genes is a cause of high morbidity in Abeokuta, Nigeria. This study was designed to determine some virulent factors among enteropathogenic E. coli in Abeokuta, Nigeria. Approximately non-repetitive 102 isolates of E. coli were recovered from clinical samples from two health facilities in Abeokuta. Biotyping using API and antibiotic susceptibility was determined, and eae and flic genes were assayed by PCR. Antibiotic resistance relatedness was performed by DendroUPGMA. Results showed that 48.0% and 52.0 % were intestinal and extra-intestinal E. coli, ampicillin recorded 100% resistance, amoxycilli/clavulanic acid 64.7%, cotrimoxazole 57.8% and 56.8% resistance against cefotaxime, at MIC >16 ug/mL, 100%, 57.8%, and 50% have MIC50 to ampicillin, tetracycline, and ceftazidime, while 74.5% and 48.0% have MIC90 to ampicillin and ceftazidime. Significant rates of 4.9%, 7.8%, and 9.8% flic, eae, and flic/eae genes were found in intestinal isolates, while 2.9%, 2.0%, and 3.9% were found in extra-intestinal (P coli pathotypes with high resistance could trigger unprecedented morbidity and mortality, mostly among children and the elderly.

  1. Identification of commensal Escherichia coli genes involved in biofilm resistance to pathogen colonization.

    Directory of Open Access Journals (Sweden)

    Sandra Da Re

    Full Text Available Protection provided by host bacterial microbiota against microbial pathogens is a well known but ill-understood property referred to as the barrier effect, or colonization resistance. Despite recent genome-wide analyses of host microbiota and increasing therapeutic interest, molecular analysis of colonization resistance is hampered by the complexity of direct in vivo experiments. Here we developed an in vitro-to-in vivo approach to identification of genes involved in resistance of commensal bacteria to exogenous pathogens. We analyzed genetic responses induced in commensal Escherichia coli upon entry of a diarrheagenic enteroaggregative E. coli or an unrelated Klebsiella pneumoniae pathogen into a biofilm community. We showed that pathogens trigger specific responses in commensal bacteria and we identified genes involved in limiting colonization of incoming pathogens within commensal biofilm. We tested the in vivo relevance of our findings by comparing the extent of intestinal colonization by enteroaggregative E. coli and K. pneumoniae pathogens in mice pre-colonized with E. coli wild type commensal strain, or mutants corresponding to identified colonization resistance genes. We demonstrated that the absence of yiaF and bssS (yceP differentially alters pathogen colonization in the mouse gut. This study therefore identifies previously uncharacterized colonization resistance genes and provides new approaches to unravelling molecular aspects of commensal/pathogen competitive interactions.

  2. [Role of constitutive and inducible repair in radiation resistance of Escherichia coli].

    Science.gov (United States)

    Gulevich, E P; Kuznetsova, V N; Verbenko, V N

    2011-07-01

    Radiation resistance of Escherichia coil cells depends on how efficiently DNA is recovered after damage, which is determined by the function of constitutive and inducible repair branches. The effects of additional mutations of the key genes of constitutive and inducible repair (recA, lexA, recB, polA, lig, gyr, recE, recO, recR, recJ, recQ, uvrD, helD, recN, and ruv) on radiation resistance were studied in E. coli K-12 strain AB 1157 and highly radiation-resistant isogenic strain Gam(r)444. An optimal balance ensuring a high gamma resistance of the Gam(r)444 radiation-resistant E. coli mutant was due to expression of the key SOS repair genes (recA, lexA, recN, and ruv) and activation of the presynaptic functions of the RecF homologous recombination pathway as a result of a possible mutation of the uvrD gene, which codes for repair helicase II. PMID:21938951

  3. Detection of antibiotic resistant enterococci and Escherichia coli in free range Iberian Lynx (Lynx pardinus).

    Science.gov (United States)

    Gonçalves, Alexandre; Igrejas, Gilberto; Radhouani, Hajer; Santos, Tiago; Monteiro, Ricardo; Pacheco, Rui; Alcaide, Eva; Zorrilla, Irene; Serra, Rodrigo; Torres, Carmen; Poeta, Patrícia

    2013-07-01

    Thirty fecal samples from wild specimens of Iberian lynx were collected and analyzed for Enterococcus spp. (27 isolates) and Escherichia coli (18 isolates) recovery. The 45 isolates obtained were tested for antimicrobial resistance, molecular mechanisms of resistance, and presence of virulence genes. Among the enterococci, Enterococcus faecium and Enterococcus hirae were the most prevalent species (11 isolates each), followed by Enterococcus faecalis (5 isolates). High percentages of resistance to tetracycline and erythromycin (33% and 30%, respectively) were detected among enterococcal isolates. The tet(M) and/or tet(L), erm(B), aac(6')-Ie-aph(2″)-Ia, ant(6)-Ia, or aph(3')-IIIa genes were detected among resistant enterococci. Virulence genes were detected in one E. faecalis isolate (cpd, cylB, and cylL) and one E. hirae isolate (cylL). High percentages of resistance were detected in E. coli isolates to tetracycline (33%), streptomycin (28%), nalidixic acid (28%), and sulfamethoxazole-trimethoprim (SXT, 22%). Additionally, the blaTEM, tet(A), aadA, cmlA, and different combinations of sul genes were detected among most ampicillin, tetracycline, streptomycin, chloramphenicol and SXT-resistant isolates, respectively. Two isolates contained a class 1 integron with the gene cassette arrays dfrA1 + aadA1 and dfrA12 + aadA2. The E. coli isolates were ascribed to phylo-groups A (n=5); B1 (n=4); B2 (n=6), and D (n=3), with the virulence gene fimA present in all E. coli isolates. This study found resistance genes in wild specimens of Iberian lynx. Thus, it is important to notice that multiresistant bacteria have reached species as rare and completely non-synanthropic as the Iberian lynx. Furthermore, the susceptibility of this endangered species to bacterial infection may be affected by the presence of these virulence and resistance genes.

  4. Influence of cyclopropane fatty acids on heat, high pressure, acid and oxidative resistance in Escherichia coli.

    Science.gov (United States)

    Chen, Yuan Yao; Gänzle, Michael G

    2016-04-01

    Heat and high pressure resistant strains of Escherichia coli are a challenge to food safety. This study investigated effects of cyclopropane fatty acids (CFAs) on stress tolerance in the heat- and pressure-resistant strain E. coli AW1.7 and the sensitive strain E. coli MG1655. The role of CFAs was explored by disruption of cfa coding for CFA synthase with an in-frame, unmarked deletion method. Both wild-type strains consumed all the unsaturated fatty acids (C16:1 and C18:1) that were mostly converted to CFAs and a low proportion to saturated fatty acid (C16:0). Moreover, E. coli AW1.7 contained a higher proportion of membrane C19:0 cyclopropane fatty acid than E. coli MG1655 (Phigh pressure and acid treatments in E. coli AW1.7, and E. coli MG1655. E. coli AW1.7 and its Δcfa mutant were more resistant to pressure and heat but less resistant to acid stress than E. coli MG1655. Heat resistance of wild-type strains and their Δcfa mutant was also assessed in beef patties grilled to an internal temperature of 71 °C. After treatment, cell counts of wild type strains were higher than those of the Δcfa mutant strains. In conclusion, CFA synthesis in E. coli increases heat, high pressure and acid resistance, and increases heat resistance in food. This knowledge on mechanisms of stress resistance will facilitate the design of intervention methods for improved pathogen control in food production.

  5. Differential epigenetic compatibility of qnr antibiotic resistance determinants with the chromosome of Escherichia coli.

    Directory of Open Access Journals (Sweden)

    María B Sánchez

    Full Text Available Environmental bacteria harbor a plethora of genes that, upon their horizontal transfer to new hosts, may confer resistance to antibiotics, although the number of such determinants actually acquired by pathogenic bacteria is very low. The founder effect, fitness costs and ecological connectivity all influence the chances of resistance transfer being successful. We examined the importance of these bottlenecks using the family of quinolone resistance determinants Qnr. The results indicate the epigenetic compatibility of a determinant with the host genome to be of great importance in the acquisition and spread of resistance. A plasmid carrying the widely distributed QnrA determinant was stable in Escherichia coli, whereas the SmQnr determinant was unstable despite both proteins having very similar tertiary structures. This indicates that the fitness costs associated with the acquisition of antibiotic resistance may not derive from a non-specific metabolic burden, but from the acquired gene causing specific changes in bacterial metabolic and regulatory networks. The observed stabilization of the plasmid encoding SmQnr by chromosomal mutations, including a mutant lacking the global regulator H-NS, reinforces this idea. Since quinolones are synthetic antibiotics, and since the origin of QnrA is the environmental bacterium Shewanella algae, the role of QnrA in this organism is unlikely to be that of conferring resistance. Its evolution toward this may have occurred through mutations or because of an environmental change (exaptation. The present results indicate that the chromosomally encoded Qnr determinants of S. algae can confer quinolone resistance upon their transfer to E. coli without the need of any further mutation. These results suggest that exaptation is important in the evolution of antibiotic resistance.

  6. Association between tetracycline consumption and tetracycline resistance in Escherichia coli from healthy Danish slaughter pigs.

    Science.gov (United States)

    Vieira, Antonio Roberto; Houe, Hans; Wegener, Henrik C; Lo Fo Wong, Danilo M A; Emborg, Hanne-Dorthe

    2009-01-01

    It has been recognized that exposure to antimicrobial agents can exert a selective pressure for the emergence of antimicrobial resistance. The objective of this study was to investigate an association between the probability of isolating a tetracycline-resistant Escherichia coli isolate from the intestinal tract of healthy pigs and patterns of tetracycline consumption in the herds of origin, together with other risk factors. Data on antimicrobial resistance, antimicrobial consumption, and pig herd demographics were obtained from different Danish surveillance programs. Descriptive statistics were performed for the risk factors in relation to the susceptibility status. Logistic regression analysis was performed to identify risk factors with significant effect on the log odds of tetracycline resistance of E. coli isolates. The model showed that an increase in the interval between last prescription and sampling date would decrease the probability of isolating a resistant E. coli isolate (p-value = 0.01). Also, a direct association between treatment incidence rate in a herd and probability of resistance was detected (p-value = 0.03). Other risk factors found to have a significant effect in the isolate susceptibility status were number of produced animals in the year and year of sampling. Other antimicrobial consumption risk factors, such as number of prescriptions and amount prescribed, although not included in the final model, presented indirect impact in the tetracycline resistance probability. From this study, we can infer that tetracycline usage, the time span between last treatment and sampling date, together with herd size and the proportion of animals being treated in a herd, increase the probability of obtaining a resistant isolate. PMID:19072081

  7. SOS response induces persistence to fluoroquinolones in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Tobias Dörr

    2009-12-01

    Full Text Available Bacteria can survive antibiotic treatment without acquiring heritable antibiotic resistance. We investigated persistence to the fluoroquinolone ciprofloxacin in Escherichia coli. Our data show that a majority of persisters to ciprofloxacin were formed upon exposure to the antibiotic, in a manner dependent on the SOS gene network. These findings reveal an active and inducible mechanism of persister formation mediated by the SOS response, challenging the prevailing view that persisters are pre-existing and formed purely by stochastic means. SOS-induced persistence is a novel mechanism by which cells can counteract DNA damage and promote survival to fluoroquinolones. This unique survival mechanism may be an important factor influencing the outcome of antibiotic therapy in vivo.

  8. Antimicrobial-resistant faecal Escherichia coli in wild mammals in central Europe: multiresistant Escherichia coli producing extended-spectrum ß-lactamases in wild boars

    DEFF Research Database (Denmark)

    Literak, I.; Dolejska, Monika; Radimersky, T.;

    2010-01-01

    Aims: To determine the presence of antibiotic-resistant faecal Escherichia coli in populations of wild mammals in the Czech Republic and Slovakia. Methods and Results: Rectal swabs or faeces collected during 2006-2008 from wild mammals were spread on MacConkey agar and MacConkey agar containing 2...... mg l-1 of cefotaxime. From plates with positive growth, one isolate was recovered and identified as E. coli. Susceptibility to 12 antibiotics was tested using the disk diffusion method. Resistance genes, class 1 and 2 integrons and gene cassettes were detected in resistant isolates by polymerase....... The prevalence of resistant isolates was 2% in small terrestrial mammals (rodents and insectivores, n(E. coli) = 242), 12% in wild ruminants and foxes (n(E. coli) = 42), while no resistant isolates were detected in brown bears (n(E. coli) = 16). In wild boars (Sus scrofa) (n(E. coli) = 290), the prevalence...

  9. SCREENING THE ANTIMICROBIAL ACTIVITY OF SOME MEDICINAL PLANTS AGAINST MULTIDRUG RESISTANCE ESCHERICHIA COLI TYPE (1

    Directory of Open Access Journals (Sweden)

    SHAZA ANWAR AL LAHAM, FRDOOS MOHAMMAD

    2014-05-01

    Full Text Available The increasing number of Escherichia coli causing mastitis and of bacteria resistant to conventional antibiotics has become aserious problem in recent years. So the search for new antibiotics and alternative products to solve this problem is the question ofthe age. This research aims to investigate the effectiveness of the extracts prepared from different parts of the following plants:Olea europea Linn (Oleaceae ، Myrtus communis Linn (Liliaceae، Majorana syriacus Linn (Laminaceae، Zingiber officinaleLinn (Zingiberaceae، Achillea falcata Linn (Asteraceae against resistant Escherichia coli Type (1. Investigation began forE.coli bacteria in 667 milk samples. The bacteria were identified culturally, morphologically and biochemically. Antibioticsusceptibility testing against E.coli by Kirby-Bauer disk diffusion method were conducted. Then using the blood agar,MacConkey agar, salmonella - shigella agar, and biochemical testing method [API 20 E testing Enterobacteriaceae] were made totype E.coli. Plants were extracted with water, absolute alcohol, then ether using a soxhlet apparatus and rotary vacuumevaporator. Then extracts susceptibility testing against antibiotic resistant E.coli Type (1 were studied. E. coli was defined asoxidase negative, indole positive, catalase positive. The studied antibiotics did not show any antibacterial effect against E.coli .By the results of the biochemical analysis (API20e on resistant E.coli , E.coli type (1 was 33.35% of the total number ofsamples. The anti-bacterial effectiveness against E.coli type (1 of ethanol extracts prepared from different parts of the studiedplants were variant, whereas the Myrtus communis extract effectively has the most powerful antibacterial effect for these bacteria,while the Zingiber officinale extract has the lowest influence.

  10. CORRELATION BETWEEN BIOFILM FORMATION OF UROPATHOGE NIC ESCHERICHIA COLI AND ITS ANTIBIOTIC RESISTANCE PATT ERN

    Directory of Open Access Journals (Sweden)

    SarojGolia

    2012-09-01

    Full Text Available ABSTRACT BACKGROUND: Microorganisms growing in multilayered cell cluste rs embedded in a matrix of extracellular polysaccharide (slime which facilitat es the adherence of these microorganisms to biomedical surfaces and protect them from host immun e system and antimicrobial therapy. There are various methods to detect biofilm producti on like Tissue Culture Plate (TCP ,Tube method (TM ,Modified Congo Red Agar Method (MCRA, bio luminescent assay ,piezoelectric sensors and fluorescent microscopic examination. OBJECTIVES : This study was conducted to compare three methods f or the detection of biofilms and compare with antibiotic sensitivity pat tern, in uropathogenic Escherichia coli. METHOD: This study was carried out at the Department of Microbiology Dr. B. R. Ambedkar Medical College from Dec 2011 to June 2012. Total n umber of 107 clinical Escherichia coli isolates were randomly selected from all age groups were subjected to biofilm detection methods and their antibiotic resistance pattern w as compared. Isolates were identified by standard phenotypic methods. Biofilm detection was te sted by TCP, TM and MCRA methods . Antibiotic susceptibility test of uropathogenic E co li was performed using Kirby –Bauer disc diffusion method according to CLSI guidelines. RESULTS: From the total of 107 clinical isolate 74 (69.1 % isolates showed biofilm formation by all the TCP, TM, CRP methods. Biofilm forming i solates from catheter associated UTI showed drug resistance to more than 6 drugs. Only 2(13.3% isolates from Asymptomatic UTI showed biofilm by TM & MCRA methods & were sensitive all d rugs. Biofilm forming isolates from symptomatic UTI showed mixed drug resistance pattern. CONCLUSION: We conclude from our study that biofilm formation is more common in catheterized patients. TCP method is more quantitati ve and reliable method for the detection of biofilm forming micro-organisms as compared to TM a nd MCRA methods. So TCP method can be recommended

  11. The serum resistome of a globally disseminated multidrug resistant uropathogenic Escherichia coli clone.

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    Minh-Duy Phan

    Full Text Available Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73% of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82% of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and

  12. The serum resistome of a globally disseminated multidrug resistant uropathogenic Escherichia coli clone.

    Science.gov (United States)

    Phan, Minh-Duy; Peters, Kate M; Sarkar, Sohinee; Lukowski, Samuel W; Allsopp, Luke P; Gomes Moriel, Danilo; Achard, Maud E S; Totsika, Makrina; Marshall, Vikki M; Upton, Mathew; Beatson, Scott A; Schembri, Mark A

    2013-01-01

    Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum) of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73%) of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS) biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82%) of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and cause disease.

  13. Evaluation of Petrifilm™ Select E. coli Count Plate medium to discriminate antimicrobial resistant Escherichia coli

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    Jensen Lars

    2008-09-01

    Full Text Available Abstract Background Screening and enumeration of antimicrobial resistant Escherichia coli directly from samples is needed to identify emerging resistant clones and obtain quantitative data for risk assessment. Aim of this study was to evaluate the performance of 3M™ Petrifilm™ Select E. coli Count Plate (SEC plate supplemented with antimicrobials to discriminate antimicrobial-resistant and non-resistant E. coli. Method A range of E. coli isolates were tested by agar dilution method comparing the Minimal Inhibitory Concentration (MIC for eight antimicrobials obtained by Mueller-Hinton II agar, MacConkey agar and SEC plates. Kappa statistics was used to assess the levels of agreement when classifying strains as resistant, intermediate or susceptible. Results SEC plate showed that 74% of all strains agreed within ± 1 log2 dilution when comparing MICs with Mueller-Hinton II media. High agreement levels were found for gentamicin, ampicillin, chloramphenicol and cefotaxime, resulting in a kappa value of 0.9 and 100% agreement within ± 1 log2 dilution. Significant variances were observed for oxytetracycline and sulphamethoxazole. Further tests showed that the observed discrepancy in classification of susceptibility to oxytetracycline by the two media could be overcome when a plate-dependent breakpoint of 64 mg/L was used for SEC plates. For sulphamethoxazole, SEC plates provided unacceptably high MICs. Conclusion SEC plates showed good agreement with Mueller-Hinton II agar in MIC studies and can be used to screen and discriminate resistant E. coli for ampicillin, cephalothin, streptomycin, chloramphenicol, cefotaxime and gentamicin using CLSI standardized breakpoints, but not for sulphamethoxazole. SEC plates can also be used to discriminate oxytetracycline-resistant E. coli if a plate-dependent breakpoint value of 64 mg/L is used.

  14. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    V.T. Nguyen; J.J. Carrique-Mas; T.H Ngo; H.M. Ho; T.T. Ha; J.I. Campbell; T.N. Nguyen; N.N. Hoang; V.M. Pham; J.A. Wagenaar; A. Hardon; Q.H. Thai; C. Schultsz

    2015-01-01

    Objectives: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods:

  15. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    NARCIS (Netherlands)

    Trung, Nguyen Vinh; Carrique-Mas, Juan J; Thi Hoa, Ngo; Mai, Ho Huynh; Tuyen, Ha Thanh; Campbell, James I; Nhung, Nguyen Thi; Nhung, Hoang Ngoc; Van Minh, Pham; Wagenaar, Jaap A; Hardon, Anita; Hieu, Thai Quoc; Schultsz, Constance

    2015-01-01

    OBJECTIVES: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. METHODS:

  16. After genomics, what proteomics tools could help us understand the antimicrobial resistance of Escherichia coli?

    Science.gov (United States)

    Radhouani, Hajer; Pinto, Luís; Poeta, Patrícia; Igrejas, Gilberto

    2012-06-01

    Proteomic approaches have been considerably improved during the past decade and have been used to investigate the differences in protein expression profiles of cells grown under a broad spectrum of growth conditions and with different stress factors including antibiotics. In Europe, the most significant disease threat remains the presence of microorganisms that have become resistant to antimicrobials and so it is important that different scientific tools are combined to achieve the largest amount of knowledge in this area of expertise. The emergence and spread of the antibiotic-resistant Gram-negative pathogens, such as Escherichia coli, can lead to serious problem public health in humans. E. coli, a very well described prokaryote, has served as a model organism for several biological and biotechnological studies increasingly so since the completion of the E. coli genome-sequencing project. The purpose of this review is to present an overview of the different proteomic approaches to antimicrobial-resistant E. coli that will be helpful to obtain a better knowledge of the antibiotic-resistant mechanism(s). This can also aid to understand the molecular determinants involved with pathogenesis, which is essential for the development of effective strategies to combat infection and to reveal new therapeutic targets. This article is part of a Special Issue entitled: Proteomics: The clinical link.

  17. L-glutamine provides acid resistance for Escherichia coli through enzymatic release of ammonia

    Institute of Scientific and Technical Information of China (English)

    Peilong Lu; Dan Ma; Yuling Chen; Yingying Guo; Guo-Qiang Chen; Haiteng Deng; Yigong Shi

    2013-01-01

    Bacteria,exemplified by enteropathogenic Escherichia coli (E.coli),,rely on elaborate acid resistance systems to survive acidic environment (such as the stomach).Comprehensive understanding of bacterial acid resistance is important for prevention and clinical treatment.In this study,we report a previously uncharacterized type of acid resistance system in E.coli that relies on L-glutamine (Gln),one of the most abundant food-borne free amino acids.Upon uptake into E.coli,Gln is converted to L-glutamate (Glu) by the acid-activated glutaminase YbaS,with concomitant release of gaseous ammonia.The free ammonia neutralizes proton,resulting in elevated intracellular pH under acidic environment.We show that YbaS and the amino acid antiporter GadC,which exchanges extracellular Gln with intracellular Glu,together constitute an acid resistance system that is sufficient for E.coli survival under extremely acidic environment.

  18. Susceptibility of multidrug resistant enterotoxigenic escherichia coli to saponin extract from phyllanthus niruri

    International Nuclear Information System (INIS)

    Escherichia coli were isolated from 140 samples of blood, urine, stool and water made up of 15.7%, 42.9% and 30.0% and 25.7% respectively. From the samples, 71.9% enterotoxigenic E. coli (ETEC), 14.3% enteropathogenic E. coli (EPEC), 7.1% enterohemorrhagic E. coil (EHEC) and 7.1% enteroinvasive E. coli (EIEC) occurred as diarrheagenic E. coli. Of the ETEC (240) isolates tested for susceptibility to eight conventional antibiotics. 110 (46.0%) showed resistance to all the tested antimicrobial agents. However, of the resistant strains; 24 (22.0%) were multidrug resistant. These were tested against 3.0 mg/mL of saponin extract from phyllanthus niruri and 13 (55.0%) of these were susceptible to the saponin. The antimicrobial activities of saponin from P. niruri are of interest since the crude extract was effective at concentration of 3.0 mg/ml to multiple resistant isolates of EEC. (author)

  19. Prevalence of antimicrobial resistance in Escherichia coli and Klebsiella spp. in rural South India.

    Science.gov (United States)

    Sekar, Ramalingam; Mythreyee, Manoharan; Srivani, Seetharaman; Amudhan, Murugesan

    2016-06-01

    The emergence and dissemination of antimicrobial resistance (AMR) is an important public health problem as resistant organisms cause difficult-to-treat infections. In this study, the prevalence of AMR in Escherichia coli and Klebsiella spp. in rural South India was examined in order to aid empirical therapy. A cross-sectional prospective study was conducted during the period from January 2012 to December 2014. Routine clinical isolates of E. coli and Klebsiella spp. were tested for antimicrobial susceptibility to β-lactams, aminoglycosides, fluoroquinolones, tetracyclines, colistin and nitrofurantoin by the Kirby-Bauer disk diffusion method and the data were documented and analyzed with one per patient analysis using WHONET software. A total of 2292 non-duplicate clinical isolates were recovered during the study period, including 1338 E. coli and 954 Klebsiella spp. The prevalence of AMR in the total isolates was as follows: amikacin, 17.3%; ertapenem, 14.4%; doripenem, 4.5%; colistin, 13.2%; and tigecycline, 4.1%. The study results indicate a high prevalence of carbapenem resistance in Klebsiella spp. especially from pus and urinary isolates, whilst the prevalence of aztreonam and fluoroquinolone resistance was very high in E. coli. PMID:27436473

  20. Virulence Profiles, Phylogenetic Background, and Antibiotic Resistance of Escherichia coli Isolated from Turkeys with Airsacculitis

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    Marcos Paulo Vieira Cunha

    2014-01-01

    Full Text Available Avian Pathogenic Escherichia coli (APEC has been studied for decades because of its economic impact on the poultry industry. Recently, the zoonotic potential of APEC and multidrug-resistant strains have emerged. The aim of this study was to characterize 225 APEC isolated from turkeys presenting airsacculitis. The results showed that 92% of strains presented a multidrug-resistance (MDR, and the highest levels of resistance were to sulfamethazine (94% and tetracycline (83%. Half of these strains were classified in phylogenetic group B2, followed by B1 (28.6%, A (17.1%, and D (4.8%. The prevalence of virulence genes was as follows: salmochelin (iroN, 95%, increased serum survival (iss, 93%, colicin V (cvi/cva, 67%, aerobactin (iucD, 67%, temperature-sensitive haemagglutinin (tsh, 56%, iron-repressible protein (irp2, 51%, invasion brain endothelium (ibeA, 31%, vacuolating autotransporter toxin (vat, 24%, K1 antigen (neuS, 19%, enteroaggregative heat-stable cytotoxin (astA, 17%, and pilus associated with pyelonephritis (papC, 15%. These results demonstrate that the majority of the investigated strains belonged to group B2 and were MDR. These data suggest that turkeys may serve as a reservoir of pathogenic and multidrug-resistance strains, reinforcing the idea that poultry plays a role in the epidemiological chain of ExPEC.

  1. ANTIBIOTIC RESISTANCE OF ESCHERICHIA COLI ISOLATED FROM UKRAINIAN BETULA VERRUCOSA EHRH. POLLEN AFTER MICROBIOLOGICAL ANALYSIS

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    Tetiana Shevtsova

    2013-08-01

    Full Text Available Seven samples of silver birch pollen from different habitat of Ukraine were investigated in order to estimate their contamination with the Enterobacteriaceae family, anaerobic bacteria and fungi. Also resistance of 108 strains of Escherichia coli isolated from seven samples of Ukrainian Betula verrucosa Ehrh. pollen against 5 antibiotics: ampicillin, chloramphenicol, meropenem, ceftriaxone and ofloxacin were determined. Disc diffusion method was used for antibiotic suceptibility testing according to EUCAST 2012. It is established the concentrations of enterobacteria ranged from 0.00 to 4.16 log cfu/g, of anaerobic bacteria – 2.48 to 4.90 log cfu/g and concentration of fungi ranged from 2.48 to 4.14 log cfu/g. Degree of pollen contamination is different depending on the habitats. The resistance of E. coli isolates was determined against ampicillin, chloramphenicol, meropenem and ofloxacin. But intermediate resistance in the 33.3% of E. coli isolates and susceptibility in the 8.3% to ceftriaxone was found out. Antibiotic resistance was evaluated for all samples of pollen in whole.

  2. Resistance patterns, ESBL genes, and genetic relatedness of Escherichia coli from dogs and owners

    Science.gov (United States)

    Carvalho, A.C.; Barbosa, A.V.; Arais, L.R.; Ribeiro, P.F.; Carneiro, V.C.; Cerqueira, A.M.F.

    2016-01-01

    Antimicrobial resistance in Escherichia coli isolated from pet dogs can be considered a potential threat of infection for the human population. Our objective was to characterize the resistance pattern, extended spectrum beta-lactamase production and genetic relatedness of multiresistant E. coli strains isolated from dogs (n = 134), their owners (n = 134), and humans who claim to have no contact with dogs (n = 44, control), searching for sharing of strains. The strains were assessed for their genetic relatedness by phylogenetic grouping and pulsed-field gel electrophoresis. Multiresistant E. coli strains were isolated from 42 (31.3%) fecal samples from pairs of dogs and owners, totaling 84 isolates, and from 19 (43.1%) control group subjects. The strains showed high levels of resistance to ampicillin, streptomycin, tetracycline, trimethoprim and sulfamethoxazole regardless of host species or group of origin. The blaTEM, blaCTX-M, and blaSHV genes were detected in similar proportions in all groups. All isolates positive for bla genes were ESBL producers. The phylogenetic group A was the most prevalent, irrespective of the host species. None of the strains belonging to the B2 group contained bla genes. Similar resistance patterns were found for strains from dogs, owners and controls; furthermore, identical PFGE profiles were detected in four (9.5%) isolate pairs from dogs and owners, denoting the sharing of strains. Pet dogs were shown to be a potential household source of multiresistant E. coli strains. PMID:26887238

  3. Characterization of Multidrug Resistant ESBL-Producing Escherichia coli Isolates from Hospitals in Malaysia

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    King-Ting Lim

    2009-01-01

    Full Text Available The emergence of Escherichia coli that produce extended spectrum β-lactamases (ESBLs and are multidrug resistant (MDR poses antibiotic management problems. Forty-seven E. coli isolates from various public hospitals in Malaysia were studied. All isolates were sensitive to imipenem whereas 36 were MDR (resistant to 2 or more classes of antibiotics. PCR detection using gene-specific primers showed that 87.5% of the ESBL-producing E. coli harbored the blaTEM gene. Other ESBL-encoding genes detected were blaOXA, blaSHV, and blaCTX-M. Integron-encoded integrases were detected in 55.3% of isolates, with class 1 integron-encoded intI1 integrase being the majority. Amplification and sequence analysis of the 5′CS region of the integrons showed known antibiotic resistance-encoding gene cassettes of various sizes that were inserted within the respective integrons. Conjugation and transformation experiments indicated that some of the antibiotic resistance genes were likely plasmid-encoded and transmissible. All 47 isolates were subtyped by PFGE and PCR-based fingerprinting using random amplified polymorphic DNA (RAPD, repetitive extragenic palindromes (REPs, and enterobacterial repetitive intergenic consensus (ERIC. These isolates were very diverse and heterogeneous. PFGE, ERIC, and REP-PCR methods were more discriminative than RAPD in subtyping the E. coli isolates.

  4. ANTIMICROBIAL DRUG RESISTANCE IN STRAINS OF Escherichia coli ISOLATED FROM FOOD SOURCES

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    Mohammed Uddin Rasheed

    2014-07-01

    Full Text Available A variety of foods and environmental sources harbor bacteria that are resistant to one or more antimicrobial drugs used in medicine and agriculture. Antibiotic resistance in Escherichia coli is of particular concern because it is the most common Gram-negative pathogen in humans. Hence this study was conducted to determine the antibiotic sensitivity pattern of E. coli isolated from different types of food items collected randomly from twelve localities of Hyderabad, India. A total of 150 samples comprising; vegetable salad, raw egg-surface, raw chicken, unpasteurized milk, and raw meat were processed microbiologically to isolate E. coli and to study their antibiotic susceptibility pattern by the Kirby-Bauer method. The highest percentages of drug resistance in isolates of E. coli were detected from raw chicken (23.3% followed by vegetable salad (20%, raw meat (13.3%, raw egg-surface (10% and unpasteurized milk (6.7%. The overall incidence of drug resistant E. coli was 14.7%. A total of six (4% Extended Spectrum β-Lactamase (ESBL producers were detected, two each from vegetable salads and raw chicken, and one each from raw egg-surface and raw meat. Multidrug resistant strains of E. coli are a matter of concern as resistance genes are easily transferable to other strains. Pathogen cycling through food is very common and might pose a potential health risk to the consumer. Therefore, in order to avoid this, good hygienic practices are necessary in the abattoirs to prevent contamination of cattle and poultry products with intestinal content as well as forbidding the use of untreated sewage in irrigating vegetables.

  5. Python erythrocytes are resistant to α-hemolysin from Escherichia coli.

    Science.gov (United States)

    Larsen, Casper K; Skals, Marianne; Wang, Tobias; Cheema, Muhammad U; Leipziger, Jens; Praetorius, Helle A

    2011-12-01

    α-Hemolysin (HlyA) from Escherichia coli lyses mammalian erythrocytes by creating nonselective cation pores in the membrane. Pore insertion triggers ATP release and subsequent P2X receptor and pannexin channel activation. Blockage of either P2X receptors or pannexin channels reduces HlyA-induced hemolysis. We found that erythrocytes from Python regius and Python molurus are remarkably resistant to HlyA-induced hemolysis compared to human and Trachemys scripta erythrocytes. HlyA concentrations that induced maximal hemolysis of human erythrocytes did not affect python erythrocytes, but increasing the HlyA concentration 40-fold did induce hemolysis. Python erythrocytes were more resistant to osmotic stress than human erythrocytes, but osmotic stress tolerance per se did not confer HlyA resistance. Erythrocytes from T. scripta, which showed higher osmotic resistance than python erythrocytes, were as susceptible to HlyA as human erythrocytes. Therefore, we tested whether python erythrocytes lack the purinergic signalling known to amplify HlyA-induced hemolysis in human erythrocytes. P. regius erythrocytes increased intracellular Ca²⁺ concentration and reduced cell volume when exposed to 3 mM ATP, indicating the presence of a P2X₇-like receptor. In addition, scavenging extracellular ATP or blocking P2 receptors or pannexin channels reduced the HlyA-induced hemolysis. We tested whether the low HlyA sensitivity resulted from low affinity of HlyA to the python erythrocyte membrane. We found comparable incorporation of HlyA into human and python erythrocyte membranes. Taken together, the remarkable HlyA resistance of python erythrocytes was not explained by increased osmotic resistance, lack of purinergic hemolysis amplification, or differences in HlyA affinity.

  6. Antimicrobial-resistant and ESBL-producing Escherichia coli in different ecological niches in Bangladesh

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    Mahmudur Rashid

    2015-07-01

    Full Text Available Introduction: The rapid and wide-scale environmental spread of multidrug-resistant bacteria in different ecosystems has become a serious issue in recent years. Objectives: To investigate the epidemiology of antimicrobial resistance and extended spectrum beta-lactamase (ESBL in Bangladeshi wild birds and aquatic environments, samples were taken from Open Bill Stork (Anastomus oscitans (OBS and the nearby water sources. Methods: Water and fresh fecal samples were collected from several locations. All samples were processed and cultured for Escherichia coli and tested for antibiotic susceptibility against commonly used antibiotics. ESBL producers were characterized at genotypic level using polymerase chain reaction (PCR, sequencing, multilocus sequence typing, and rep-PCR. Results and discussion: A total of 76 E. coli isolates from the 170 OBS and 8 E. coli isolates from three river sources were isolated. In total, 29% of E. coli isolated from OBS and all of the E. coli isolated from water sources were resistant to at least one of the tested antimicrobials. Resistant phenotypes were observed with all antimicrobials except tigecycline, gentamicin, imipenem, and chloramphenicol. Multidrug resistance was observed in 2.6% of OBS and 37.5% of the water isolates. Also, 1.2% of the ESBL-producing E. coli were isolated from OBS, whereas 50% of the E. coli isolated from water sources were ESBL producers possessing the CTX-M-15 gene. The most concerning aspect of our findings was the presence of human-associated E. coli sequence types in the water samples, for example, ST156-complex156, ST10-complex10 and ST46. Conclusion: This study reports the presence of multidrug-resistant ESBL-producing E. coli in OBSs and nearby aquatic sources in Bangladesh.

  7. 环丙沙星联用磷霉素抗尿路感染耐药铜绿假单胞菌的协同作用体外研究%On the In Vitro Synergistic Effect of Ciprofloxacin Combined with Fosfomycin against Drug-Resistant Pseudomonas Aeruginosa Isolates from Urinary Tract Infections

    Institute of Scientific and Technical Information of China (English)

    宋洁; 何召云; 宫海燕; 许思权; 陈先华

    2015-01-01

    目的:观察环丙沙星和磷霉素联合应用抗尿路感染耐药铜绿假单胞菌的体外协同作用。方法采用常规方法进行细菌分离和菌种鉴定。最低抑菌浓度( MIC )测定采用微量肉汤稀释法,联合抑菌浓度指数( FICI )测定采用棋盘法。结果82株耐环丙沙星铜绿假单胞菌中,环丙沙星和磷霉素联合应用对22株细菌有协同抗菌作用,占26.83%。急性杀菌作用中,选取环丙沙星和磷霉素联合应用后协同抗菌作用和环丙沙星 MIC降低均最明显的铜绿假单胞菌P34和P58作为研究对象,结果在药物处理8 h时,环丙沙星和磷霉素联合处理组的细菌数明显低于两种药物单独处理组。浊度试验结果显示,药物处理3h后,联合用药组与单独用药组细菌浊度出现明显差异。结论环丙沙星和磷霉素联合应用不但具有抗耐环丙沙星铜绿假单胞菌的协同作用,且具有较强的杀菌效果和溶菌作用。%Objective To investigate the in vitro synergistic effect of ciprofloxacin combined with fosfomycin on ciprofloxacin-resistant Pseudomonas aeruginosa clinical isolates from urinary tract infections. Methods The isolation and identification of Pseudomonas aeru-ginosa were performed by using the traditional procedures. The minimum inhibitory concentration ( MIC ) testing was determined by using the microdilution broth method. The fractional inhibitory concentration index ( FICI ) was tested by using the checkerboard method. Results Among the 82 ciprofloxacin-resistant Pseudomonas aeruginosa isolates, the synergistic effect of ciprofloxacin combined with fosfomycin was observed in 22 strains ( 26. 83%) . In the acute bactericidal effect experiments, Pseudomonas aeruginosa isolates P34 and P58 as the most obvious synergistic effect and the reduced MIC of ciprofloxacin were selected as the research subjects. The results showed that the viable cell count at 8 h after medication treatment in the

  8. 环丙沙星联用磷霉素抗尿路感染耐药铜绿假单胞菌的协同作用体外研究%On the In Vitro Synergistic Effect of Ciprofloxacin Combined with Fosfomycin against Drug-Resistant Pseudomonas Aeruginosa Isolates from Urinary Tract Infections

    Institute of Scientific and Technical Information of China (English)

    宋洁; 何召云; 宫海燕; 许思权; 陈先华

    2015-01-01

    Objective To investigate the in vitro synergistic effect of ciprofloxacin combined with fosfomycin on ciprofloxacin-resistant Pseudomonas aeruginosa clinical isolates from urinary tract infections. Methods The isolation and identification of Pseudomonas aeru-ginosa were performed by using the traditional procedures. The minimum inhibitory concentration ( MIC ) testing was determined by using the microdilution broth method. The fractional inhibitory concentration index ( FICI ) was tested by using the checkerboard method. Results Among the 82 ciprofloxacin-resistant Pseudomonas aeruginosa isolates, the synergistic effect of ciprofloxacin combined with fosfomycin was observed in 22 strains ( 26. 83%) . In the acute bactericidal effect experiments, Pseudomonas aeruginosa isolates P34 and P58 as the most obvious synergistic effect and the reduced MIC of ciprofloxacin were selected as the research subjects. The results showed that the viable cell count at 8 h after medication treatment in the ciprofloxacin and fosfomycin combination treatment group was significantly fewer than that of the single drug treatment group. The turbidity test results showed that the significant difference at 3 h after medica-tion treatment was observed between the ciprofloxacin and fosfomycin combination treatment group and the single drug treatment group. Conclusion The combination of ciprofloxacin and fosfomycin not only induces a synergistic effect on ciprofloxacin-resistant Pseu-domonas aeruginosa strains, but also has a strong bactericidal effect and bacteriolytic effect.%目的:观察环丙沙星和磷霉素联合应用抗尿路感染耐药铜绿假单胞菌的体外协同作用。方法采用常规方法进行细菌分离和菌种鉴定。最低抑菌浓度( MIC )测定采用微量肉汤稀释法,联合抑菌浓度指数( FICI )测定采用棋盘法。结果82株耐环丙沙星铜绿假单胞菌中,环丙沙星和磷霉素联合应用对22株细菌有协同抗菌作用,占26

  9. Spanish multicenter study of the epidemiology and mechanisms of amoxicillin-clavulanate resistance in Escherichia coli.

    Science.gov (United States)

    Ortega, Adriana; Oteo, Jesús; Aranzamendi-Zaldumbide, Maitane; Bartolomé, Rosa M; Bou, Germán; Cercenado, Emilia; Conejo, M Carmen; González-López, Juan José; Marín, Mercedes; Martínez-Martínez, Luis; Merino, María; Navarro, Ferran; Oliver, Antonio; Pascual, Alvaro; Rivera, Alba; Rodríguez-Baño, Jesús; Weber, Irene; Aracil, Belén; Campos, José

    2012-07-01

    We conducted a prospective multicenter study in Spain to characterize the mechanisms of resistance to amoxicillin-clavulanate (AMC) in Escherichia coli. Up to 44 AMC-resistant E. coli isolates (MIC ≥ 32/16 μg/ml) were collected at each of the seven participant hospitals. Resistance mechanisms were characterized by PCR and sequencing. Molecular epidemiology was studied by pulsed-field gel electrophoresis (PFGE) and by multilocus sequence typing. Overall AMC resistance was 9.3%. The resistance mechanisms detected in the 257 AMC-resistant isolates were OXA-1 production (26.1%), hyperproduction of penicillinase (22.6%), production of plasmidic AmpC (19.5%), hyperproduction of chromosomic AmpC (18.3%), and production of inhibitor-resistant TEM (IRT) (17.5%). The IRTs identified were TEM-40 (33.3%), TEM-30 (28.9%), TEM-33 (11.1%), TEM-32 (4.4%), TEM-34 (4.4%), TEM-35 (2.2%), TEM-54 (2.2%), TEM-76 (2.2%), TEM-79 (2.2%), and the new TEM-185 (8.8%). By PFGE, a high degree of genetic diversity was observed although two well-defined clusters were detected in the OXA-1-producing isolates: the C1 cluster consisting of 19 phylogroup A/sequence type 88 [ST88] isolates and the C2 cluster consisting of 19 phylogroup B2/ST131 isolates (16 of them producing CTX-M-15). Each of the clusters was detected in six different hospitals. In total, 21.8% of the isolates were serotype O25b/phylogroup B2 (O25b/B2). AMC resistance in E. coli is widespread in Spain at the hospital and community levels. A high prevalence of OXA-1 was found. Although resistant isolates were genetically diverse, clonality was linked to OXA-1-producing isolates of the STs 88 and 131. Dissemination of IRTs was frequent, and the epidemic O25b/B2/ST131 clone carried many different mechanisms of AMC resistance. PMID:22491692

  10. New Synthetic Method of Ciprofloxacin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new synthetic method of ciprofloxacin is started with 2,4-dichloro-5-fluoroacetophenone, via oxaly lation, ethoxymethylenation, amination, cyclization, hydrolysis, decarbonylation and piperazination. The reaction temperature is moderate and the operation is easily controlled. Additional four new compounds are prepared by the method.

  11. New Synthetic Method of Ciprofloxacin

    Institute of Scientific and Technical Information of China (English)

    陈英奇; 戴立言

    2001-01-01

    A new synthetic method of ciprofloxacin is started with 2,4-dichloro-5-fluoroacetophenone, via oxaly-lation, ethoxymethylenation, amination, cyclization, hydrolysis, decarbonylation and piperazination. The reaction temperature is moderate and the operation is easily controlled. Additional four new compounds are prepared by the method.

  12. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

    Directory of Open Access Journals (Sweden)

    Islam Rezuanul

    2011-03-01

    Full Text Available Abstract Background Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Methods Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. Results All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm. Conclusion Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.

  13. Identification of a novel plasmid-mediated colistin-resistance gene, mcr-2, in Escherichia coli, Belgium, June 2016.

    Science.gov (United States)

    Xavier, Basil Britto; Lammens, Christine; Ruhal, Rohit; Kumar-Singh, Samir; Butaye, Patrick; Goossens, Herman; Malhotra-Kumar, Surbhi

    2016-07-01

    We identified a novel plasmid-mediated colistin-resistance gene in porcine and bovine colistin-resistant Escherichia coli that did not contain mcr-1. The gene, termed mcr-2, a 1,617 bp phosphoethanolamine transferase harboured on an IncX4 plasmid, has 76.7% nucleotide identity to mcr-1. Prevalence of mcr-2 in porcine colistin-resistant E. coli (11/53) in Belgium was higher than that of mcr-1 (7/53). These data call for an immediate introduction of mcr-2 screening in ongoing molecular epidemiological surveillance of colistin-resistant Gram-negative pathogens. PMID:27416987

  14. Lysogenic Conversion and Phage Resistance Development in Phage Exposed Escherichia coli Biofilms

    Directory of Open Access Journals (Sweden)

    Abram Aertsen

    2013-01-01

    Full Text Available In this study, three-day old mature biofilms of Escherichia coli were exposed once to either a temperate Shiga-toxin encoding phage (H-19B or an obligatory lytic phage (T7, after which further dynamics in the biofilm were monitored. As such, it was found that a single dose of H-19B could rapidly lead to a near complete lysogenization of the biofilm, with a subsequent continuous release of infectious H-19B particles. On the other hand, a single dose of T7 rapidly led to resistance development in the biofilm population. Together, our data indicates a profound impact of phages on the dynamics within structured bacterial populations.

  15. Lysogenic conversion and phage resistance development in phage exposed Escherichia coli biofilms.

    Science.gov (United States)

    Moons, Pieter; Faster, David; Aertsen, Abram

    2013-01-01

    In this study, three-day old mature biofilms of Escherichia coli were exposed once to either a temperate Shiga-toxin encoding phage (H-19B) or an obligatory lytic phage (T7), after which further dynamics in the biofilm were monitored. As such, it was found that a single dose of H-19B could rapidly lead to a near complete lysogenization of the biofilm, with a subsequent continuous release of infectious H-19B particles. On the other hand, a single dose of T7 rapidly led to resistance development in the biofilm population. Together, our data indicates a profound impact of phages on the dynamics within structured bacterial populations. PMID:23344561

  16. Multidrug-resistant and epidemic clones of Escherichia coli from natural beds of Venus clam.

    Science.gov (United States)

    Vignaroli, C; Di Sante, L; Leoni, F; Chierichetti, S; Ottaviani, D; Citterio, B; Biavasco, F

    2016-10-01

    Epidemic Escherichia coli clones have been recovered in marine sediment along the coast of Marche, an Adriatic region in central Italy. In the present study, E. coli strains from the clam Chamelea gallina, sampled from seven natural beds in the same area, were detected. Selected E. coli isolates from all sampling sites were screened for antimicrobial susceptibility, genetic diversity and correlation. The majority (60%) belonged to phylogroups A or B1, 31% to the other groups (B2, C, D, E, F), 8% to cryptic clades, and 1% were untypable. Moreover, 33.3% of isolates were resistant to at least one drug and 11% were multidrug resistant (MDR). The most common resistance was to tetracycline, ampicillin, and streptomycin. No clonality was detected, but the strains' high genetic heterogeneity pointed at multiple sources of microbiological contamination. MLST analysis found potentially pathogenic and even epidemic MDR strains in clams collected in class A (ST746 and ST46) and class B (ST393, ST58 and ST131) areas, indicating that strains of clinical origin are detectable in clams. These data highlight that eating raw or lightly cooked clams may pose a health risk if purification is not performed or is ineffective. PMID:27375238

  17. Mutant radiation-resistance alleles from the Escherichia coli Gamr444 mutant: Cloning and preliminary characterization

    International Nuclear Information System (INIS)

    Mutant alleles Gamr, which are able to increase the resistance to radiation of Escherichia coli wild-type cells, were cloned from the hyperradioresistant mutant Gamr444 on plasmid mini-Mu-vector MudII4042. The influence of recombinant plasmids on the sensitivity of wild-type and mutant (recA and htpR) cells to γ-irradiation was studied. It was shown that the enhanced resistance of the Gamr444 strain to radiation was caused by mutations of two different classes, dominant and recessive. The cloned recessive mutation gamr12 increases resistance to radiation only after homogenotization, that is, radiation-induced transfer from the plasmid to the chromosome, and it imposes constitutive expression of the heat-shock promoter htpG. Dominant mutant gamr alleles are active in the trans-position. A mutation-insertion into a chromosomal gene impaired by one of the dominant mutations, gamr18, was constructed. The insertion causes drastic cell radiosensitization on the recBC sbcB background and probably disturbs the RecF pathway of recombination and repair. Dominant plasmids of the second type lead to the RecA-independent inhibition of DNA postirradiation degradation. The radioprotective action of recessive and dominant gamr mutations is additive

  18. Cefotaxime-resistant Escherichia coli in broiler farms-A cross-sectional investigation in Germany.

    Science.gov (United States)

    Hering, Johanna; Frömke, Cornelia; von Münchhausen, Christiane; Hartmann, Maria; Schneider, Bettina; Friese, Anika; Rösler, Uwe; Kreienbrock, Lothar; Hille, Katja

    2016-03-01

    In this investigation the farm prevalence of cefotaxime-resistant Escherichia coli (CREC) in German broiler farms was evaluated. In total, 59 flocks on 34 broiler farms were sampled in four agricultural regions of Germany. Per broiler flock, three faecal samples, a pair of boot swabs and one dust sample were taken and examined for the presence of CREC. After pre-enrichment of sample material in Luria-Bertani-broth, the broth was streaked onto MacConkey agar containing 1mg/l cefotaxime (CTX). CREC isolates were detected in at least one sample from each flock resulting in a farm prevalence of 100%. The proportion of positive samples was high in all three sample types. Of 177 collective faecal samples 81.9% were positive, of 59 boot swabs and 59 dust samples 79.7% and 62.7% were positive. In conclusion, the prevalence of broiler farms with cefotaxime-resistant E. coli in Germany is very high. We suggest that the analysis of collective faecal samples is sufficient to determine the CREC farm status. In addition to other studies our study supports the finding that cefotaxime resistance is a good proxy for the presence of ESBL- or plasmidic AmpC-beta-lactamases. PMID:26783199

  19. Expanded Genetic Codes Create New Mutational Routes to Rifampicin Resistance in Escherichia coli.

    Science.gov (United States)

    Hammerling, Michael J; Gollihar, Jimmy; Mortensen, Catherine; Alnahhas, Razan N; Ellington, Andrew D; Barrick, Jeffrey E

    2016-08-01

    Until recently, evolutionary questions surrounding the nature of the genetic code have been mostly limited to the realm of conjecture, modeling, and simulation due to the difficulty of altering this fundamental property of living organisms. Concerted genome and protein engineering efforts now make it possible to experimentally study the impact of alternative genetic codes on the evolution of biological systems. We explored how Escherichia coli strains that incorporate a 21st nonstandard amino acid (nsAA) at the recoded amber (TAG) stop codon evolve resistance to the antibiotic rifampicin. Resistance to rifampicin arises from chromosomal mutations in the β subunit of RNA polymerase (RpoB). We found that a variety of mutations that lead to substitutions of nsAAs in the essential RpoB protein confer robust rifampicin resistance. We interpret these results in a framework in which an expanded code can increase evolvability in two distinct ways: by adding a new letter with unique chemical properties to the protein alphabet and by altering the mutational connectivity of amber-adjacent codons by converting a lethal nonsense mutation into a missense mutation. Finally, we consider the implications of these results for the evolution of alternative genetic codes. In our experiments, reliance on a mutation to a reassigned codon for a vital trait is not required for the long-term maintenance of an expanded genetic code and may even destabilize incorporation of an nsAA, a result that is consistent with the codon capture model of genetic code evolution. PMID:27189550

  20. Mechanisms of antibiotic resistance to enrofloxacin in uropathogenic Escherichia coli in dog.

    Science.gov (United States)

    Piras, Cristian; Soggiu, Alessio; Greco, Viviana; Martino, Piera Anna; Del Chierico, Federica; Putignani, Lorenza; Urbani, Andrea; Nally, Jarlath E; Bonizzi, Luigi; Roncada, Paola

    2015-09-01

    Escherichia coli (E. coli) urinary tract infections (UTIs) are becoming a serious problem both for pets and humans (zoonosis) due to the close contact and to the increasing resistance to antibiotics. This study has been performed in order to unravel the mechanism of induced enrofloxacin resistance in canine E. coli isolates that represent a good tool to study this pathology. The isolated E. coli has been induced with enrofloxacin and studied through 2D DIGE and shotgun MS. Discovered differentially expressed proteins are principally involved in antibiotic resistance and linked to oxidative stress response, to DNA protection and to membrane permeability. Moreover, since enrofloxacin is an inhibitor of DNA gyrase, the overexpression of DNA starvation/stationary phase protection protein (Dsp) could be a central point to discover the mechanism of this clone to counteract the effects of enrofloxacin. In parallel, the dramatic decrease of the synthesis of the outer membrane protein W, which represents one of the main gates for enrofloxacin entrance, could explain additional mechanism of E. coli defense against this antibiotic. All 2D DIGE and MS data have been deposited into the ProteomeXchange Consortium with identifier PXD002000 and DOI http://dx.doi.org/10.6019/PXD002000. This article is part of a Special Issue entitled: HUPO 2014. PMID:26066767

  1. Fluoroquinolone-resistant Escherichia coli isolated from healthy broilers with previous exposure to fluoroquinolones: Is there a link?

    OpenAIRE

    Moniri, Rezvan; Dastehgoli, Kamran

    2011-01-01

    The occurrence of resistance to quinolones and fluoroquinolones in Escherichia coli isolated from healthy chickens and its relation to previous use of fluoroquinolones in Kashan, Iran, was evaluated. A total of 181 E. coli isolates was collected. Ninety-five (52.5%) of the chickens had a history of previous use of both flumequine and enrofloxacin; 86 (47.5%) chickens had not been exposed to antimicrobial agents previously. The proportion of strains resistant to nalidixic acid and ciprofloxaci...

  2. Heterogeneity among Virulence and Antimicrobial Resistance Gene Profiles of Extraintestinal Escherichia coli Isolates of Animal and Human Origin

    OpenAIRE

    Maynard, Christine; Bekal, Sadjia; Sanschagrin, François; Levesque, Roger C.; Brousseau, Roland; Masson, Luke; Larivière, Serge; Harel, Josée

    2004-01-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) isolates collected from different infected animals and from human patients with extraintestinal infections in 2001 were characterized for their phenotypic and genotypic antimicrobial resistance profiles, genotypes, and key virulence factors. Among the 10 antimicrobial agents tested, resistance to ampicillin, tetracycline, and sulfonamides was most frequent. Multiresistant strains were found in both the animal and the human groups of isolates...

  3. Characteristics of cefotaxime-resistant Escherichia coli from wild birds in the Netherlands.

    Science.gov (United States)

    Veldman, Kees; van Tulden, Peter; Kant, Arie; Testerink, Joop; Mevius, Dik

    2013-12-01

    Cloacal swabs from carcasses of Dutch wild birds obtained in 2010 and 2011 were selectively cultured on media with cefotaxime to screen for the presence of extended-spectrum β-lactamase (ESBL)/AmpC-producing Escherichia coli. Subsequently, all cefotaxime-resistant E. coli isolates were tested by broth microdilution and microarray. The presence of ESBL/AmpC and coexisting plasmid-mediated quinolone resistance (PMQR) genes was confirmed by PCR and sequencing. To determine the size of plasmids and the location of ESBL and PMQR genes, S1 pulsed-field gel electrophoresis (PFGE) was performed on transformants, followed by Southern blot hybridization. The study included 414 cloacal swabs originating from 55 different bird species. Cefotaxime-resistant E. coli isolates were identified in 65 birds (15.7%) from 21 different species. In all, 65 cefotaxime-resistant E. coli ESBL/AmpC genes were detected, mainly comprising variants of blaCTX-M and blaCMY-2. Furthermore, PMQR genes [aac(6')-lb-cr, qnrB1, and qnrS1] coincided in seven cefotaxime-resistant E. coli isolates. Overall, replicon typing of the ESBL/AmpC-carrying plasmids demonstrated the predominant presence of IncI1 (n = 31) and variants of IncF (n = 18). Our results indicate a wide dissemination of ESBL and AmpC genes in wild birds from The Netherlands, especially among aquatic-associated species (waterfowl, gulls, and waders). The identified genes and plasmids reflect the genes found predominantly in livestock animals as well as in humans. PMID:24038683

  4. ANTIBACTERIAL ACTIVITY OF SOME WILD MEDICAL PLANTS EXTRACT TO ANTIBIOTIC RESISTANT ESCHERICHIA COLI

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2013-02-01

    Full Text Available Antibiotics are probably the most successful family of drugs so far developed for improving human health. Because of increasing resistance to antibiotics of many bacteria, plant extracts and plant compounds are of new interest as antiseptics and antimicrobial agents in medicine. In this study, we researched antimicrobial effects of extracts of some medical plants (Tussilagofarfara, Equisetum arvense, Sambucusnigra, Aesculushippocastanumand Taraxacumofficinale from Slovakia to antibiotic resistant and antibiotic sensitive bacteria isolated from milk of cows and mare, which were breeded in different conditions. Microorganisms which were used in this experiment we isolated from milk from conventional breeding of cows (tenE. coli strains and from ecological breeding of Lipicanmare (tenE. coli strains by sterile cotton swabs. For antibiotic susceptibility testing was used disc diffusion method according by EUCAST. After dried at room temperature we weighed 50 g of crushed medical plants (parts and it were to extract in 400 ml methanol for two weeks at room temperature. For antimicrobial susceptibility testing of medical plants extract blank discs with 6 mm diameter disc diffusion method was used. We determined that all Escherichia coli strains isolated from milk of conventional breeding of cows were resistant to ampicillin and chloramphenicol. We determined that all tested ampicillin and chloramphenicol resistant E. coli strains isolated from conventional breeding of cow showed susceptibility to all used medical plants extracts. In difference, we determined that antibiotic susceptible E. coli strains isolated from ecological breeding of Lipicanmare were susceptible to Tussilagofarfara extract only. From these results we could be conclude some observations, which could be important step in treatment of bacterial infections caused by antibiotic resistant bacteria and it could be important knowledge for treatment of livestock in conventional breeding

  5. Risk factors for occurrence of cephalosporin-resistant Escherichia coli in Norwegian broiler flocks.

    Science.gov (United States)

    Mo, Solveig Sølverød; Kristoffersen, Anja Bråthen; Sunde, Marianne; Nødtvedt, Ane; Norström, Madelaine

    2016-08-01

    A longitudinal study of 27 broiler farms including 182 broiler flocks was performed to determine risk factors for occurrence of cephalosporin-resistant Escherichia coli in Norwegian broiler flocks. Information regarding possible risk factors was collected by an online questionnaire and by samples obtained from broiler and parent flocks during the study period. Additional information was provided by the broiler production company. The prevalence of cephalosporin-resistant E. coli in parent flocks and broiler flocks sampled in the study was estimated. Cephalosporin-resistant E. coli was detected in 13.8% of the parent flocks and 22.5% of the broiler flocks included in the study. A multivariable generalized linear model was used to estimate risk factors. The risk for occurrence of cephalosporin-resistant E. coli was associated with the status of the previous flock in the broiler house (odds ratio=12.7), number of parent flocks supplying the broiler flock with day-old chickens (odds ratio=6.3), routines for disinfection of floor between production cycles (odds ratio=0.1), and transport personnel entering the room where the broilers are raised (odds ratio=9.3). Our findings highlights that implementation of a high level of biosecurity with a minimal number of people entering the broiler house during production cycles, as well as rigorous cleaning and disinfection routines between production cycles will contribute to a decrease in the occurrence of cephalosporin-resistant E. coli in broiler flocks provided that there is no selection pressure from antimicrobial use in the broiler production. PMID:27435654

  6. Excretion of ciprofloxacin in sweat and multiresistant Staphylococcus epidermidis

    DEFF Research Database (Denmark)

    Høiby, N; Jarløv, J O; Kemp, M;

    1997-01-01

    BACKGROUND: Staphylococcus epidermidis develops resistance to ciprofloxacin rapidly. That this antibiotic is excreted in apocrine and eccrine sweat of healthy individuals might be the reason for the development of such resistance. We assessed whether S epidermidis isolated from the axilla and nasal...... in S epidermidis from axilla and nostrils was monitored during and 2 months after the treatment. Genotyping of S epidermidis was done by restriction fragment length polymorphism. FINDINGS: The mean concentration of ciprofloxacin in sweat increased during the 7 days of treatment-from 2.2 micrograms/mL 2.......5 h after the first tablet to 2.5 micrograms/mL after the fifth tablet, and 5.5 micrograms/mL after the 13th tablet. All persons harboured susceptible S epidermidis (minimal inhibitory concentration [MIC] 0.25 microgram/mL) in axilla and nostrils before treatment. Four resistant strains were detected...

  7. Prevalence and antimicrobial resistance profile of Escherichia coli and salmonella isolated from diarrheic calves

    DEFF Research Database (Denmark)

    Ansari, A.R.M.I.H.; Rahman, M.M.; Islam, Md Zohorul;

    2014-01-01

    a high sensitivity was found towards Ciprofloxacin, Levofloxacillin, Azithromycin and Cefotaxime. Serotyping was done by using specific antisera to identify variants of the somatic (O) and flagellar (H) antigens. Cultural and biochemical features also reveal the presence of pathogens in the...

  8. Burden of antimicrobial resistance in European hospitals : excess mortality and length of hospital stay associated with bloodstream infections due to Escherichia coli resistant to third-generation cephalosporins

    NARCIS (Netherlands)

    de Kraker, M. E. A.; Wolkewitz, M.; Davey, P. G.; Koller, W.; Berger, J.; Nagler, J.; Icket, C.; Kalenic, S.; Horvatic, J.; Seifert, H.; Kaasch, A.; Paniara, O.; Argyropoulou, A.; Bompola, M.; Smyth, E.; Skally, M.; Raglio, A.; Dumpis, U.; Kelmere, A. Melbarde; Borg, M.; Xuereb, D.; Ghita, M. C.; Noble, M.; Kolman, J.; Grabljevec, S.; Turner, D.; Lansbury, L.; Grundmann, H.

    2011-01-01

    This study determined excess mortality and length of hospital stay (LOS) attributable to bloodstream infection (BSI) caused by third-generation-cephalosporin-resistant Escherichia coli in Europe. A prospective parallel matched cohort design was used. Cohort I consisted of patients with third-generat

  9. Formation of hydroxyl radicals contributes to the bactericidal activity of ciprofloxacin against Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jensen, Peter Ø.; Briales, Alejandra; Brochmann, Rikke Prejh;

    2014-01-01

    induction of cytotoxic hydroxyl radicals (OH˙) during antibiotic treatment of planktonically grown cells may contribute to action of the commonly used antibiotic ciprofloxacin on P. aeruginosa biofilms. For this purpose, WT PAO1, a catalase deficient ΔkatA and a ciprofloxacin resistant mutant of PAO1 (gyr...

  10. Adaptation mechanisms of Escherichia Coli to the ultraviolet light I. Isolation of mutants resistant to ultraviolet light

    International Nuclear Information System (INIS)

    The objective of this work is to study the adaptation mechanisms of Escherichia coli to the ultraviolet light of 254 nm (W), a component of the solar light that induces a variety of damages in the DNA of the cells exposed, which should be eliminated in order to avoid its lethal and mutagenic effects. Inside this first report, the results obtained about the resistance to UV radiation of 5 independent populations of Escherichia coli, which were subjected in parallel form to 80 successive exposures of UV light with inserted periods of growth are reported. (Author)

  11. IbeR facilitates stress-resistance, invasion and pathogenicity of avian pathogenic Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Shaohui Wang

    Full Text Available Systemic infections by avian pathogenic Escherichia coli (APEC are economically devastating to poultry industries worldwide. IbeR, located on genomic island GimA, was shown to serve as an RpoS-like regulator in rpoS gene mutation neonatal meningitis E. coli (NMEC RS218. However, the role of IbeR in pathogenicity of APEC carrying active RpoS has not yet been investigated. We showed that the APEC IbeR could elicit antibodies in infected ducks, suggesting that IbeR might be involved in APEC pathogenicity. To investigate the function of IbeR in APEC pathogenesis, mutant and complementation strains were constructed and characterized. Inactivation of ibeR led to attenuated virulence and reduced invasion capacity towards DF-1 cells, brains and cerebrospinal fluid (CSF in vitro and in vivo. Bactericidal assays demonstrated that the mutant strain had impaired resistance to environmental stress and specific pathogen-free (SPF chicken serum. These virulence-related phenotypes were restored by genetic complementation. Quantitative real-time reverse transcription PCR revealed that IbeR controlled expression of stress-resistance genes and virulence genes, which might led to the associated virulence phenotype.

  12. Screening of Chinese Herbal Medicines Resistant to Chicken Escherichia coli and Infectious Laryngotracheitis Virus

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to screen Chinese herbal medicines resistant to Chicken Escherichia coli and infectious laryngotracheitis virus. [Methed] Conven- tional punch method, test tube method and plate dilution method were adopted for in vitro susceptibility test of chicken E, coil strains O5 and O8 using 13 kinds of Chi- nese herbal medicines including Sanguisorba officinalis, Coptis chinensis, Anemar- rhena asphodeloides, Strobilanthes cusia, Agastache rugosa, etc.; chicken embryo inoculation experiment was adopted to screen Chinese herbal medicines resistant to chicken infectious laryngotracheitis virus. [Result] Sanguisorba officinalis, Fructus mume, Rheum officinale, Coptis chinensis, Herba Taraxaci, Anemarrhena asphode- Ioides, Scutellaria baicalensis and Rhizoma Fagopyri Cymosi had ideal antibacterial effect against chicken E. coil strain O5; Sanguisorba officinalis, Fructus mume, Rheum officinale, Coptis chinensis, Herba taraxaci and Rhizoma Fagopyri Cymosi had ideal antibacterial effect against chicken E. coil strain 08; other Chinese herbal medicines showed relatively poor or no antibacterial effect. Results of chicken embryo inoculation experiment showed that nine kinds of Chinese herbal medicines showed relatively strong anti-lLTV effect, including Forsythia suspensa, Radix Isatidis, Fofium isatidis, Flos Ionicerae, Radix codonopsis, Radix astragali, Atractylodes, Radix gly- cyrrhizae, and Pericarpium granati. [Conclusion] The study laid the foundation for fur- ther development of Chinese herbal compound preparations to treat chicken cofibacil- Iosis, infectious laryngotracheitis and other bacterial, viral diseases.

  13. Virulence Factors and Antibiotic Resistance in Uropathogenic and Commensal Escherichia coli Isolates

    Directory of Open Access Journals (Sweden)

    Iraj Sedighi

    2016-10-01

    Full Text Available Background: Urinary Tract Infections (UTIs, including cystitis and pyelonephritis, are the most common infectious diseases in childhood. Aim and Objectives: Escherichia coli (E. coli account for as much as 90% of the community-acquired and also 50% of nosocomial UTIs. Therefore, the identification of E. coli strains and antibiotic resistance patterns is important for both clinical and epidemiological implications. Material and Methods: To characterize uropathogenic strains E. coli, we studied 100 strains recovered from both urine samples of children aged less than 7 years with community-acquired UTIs and stool samples of healthy children, respectively. Results: We assessed Virulence Factors (VFs and drug sensitivities of E. coli isolates. Drug sensitivities of the isolates were 94% (amikacin, 90% (nitrofurantoin, 66% (gentamicin, 56% (cefixime, 40% (nalidixic acid and 28% (cotrimoxazol. Laboratory tests showed that the prevalence of virulence factors ranged from 18% for hemolysin and P-fimbriae to 2% for type1-fimbriae. Most drug resistance was cotrimoxazole and amikacin was the lowest. P-fimbriae and hemolysin in uropathogenic E. coli were more frequent than non-pathogen type of E. coli. Conclusion: Although amikacin appeared to be the first choice for UTI in children, but nitrofurantoin seems to be practical and could be considered as the selective choice for uncomplicated lower UTIs.

  14. Antimicrobial-Resistant Escherichia coli Survived in Dust Samples for More than 20 Years.

    Science.gov (United States)

    Schulz, Jochen; Ruddat, Inga; Hartung, Jörg; Hamscher, Gerd; Kemper, Nicole; Ewers, Christa

    2016-01-01

    In a retrospective study, 119 sedimentation dust samples stored between five and 35 years from various barns of intensive livestock farming were evaluated for the occurrence of cultivatable Escherichia coli. Growth of E. coli occurred in 54 samples. Successful cultivation was achieved in samples from as early as 1994. The frequency of detection increased from earlier to later time periods, but the concentrations, which ranged between 3.4 × 10(2) and 1.1 × 10(5) colony-forming units per gram, did not correlate with sample age (Spearman rank correlation; p > 0.05). We hypothesize that E. coli cells survived in dust samples without cell division because of the storage conditions. Dry material (dust) with low water activities (arithmetic mean hen houses (p = 0.01 and p = 0.02, respectively). Sample origin and storage conditions may have influenced the number of antimicrobial resistances. Overall, we found that under particular conditions, dust from farm animal houses can be reservoirs for antimicrobial-resistant E. coli for at least 20 years. The survival strategies that allow E. coli to survive such long periods in environmental samples are not fully understood and could be an interesting research topic for future studies. PMID:27375587

  15. Role of uropathogenic Escherichia coli OmpT in the resistance against human cathelicidin LL-37.

    Science.gov (United States)

    Brannon, John R; Thomassin, Jenny-Lee; Desloges, Isabelle; Gruenheid, Samantha; Le Moual, Hervé

    2013-08-01

    Uropathogenic Escherichia coli (UPEC) strains are among the most prevalent causative agents of urinary tract infections. To establish infection, UPEC must overcome the bactericidal action of host antimicrobial peptides. Previously, the enterohaemorrhagic E. coli outer membrane protease, OmpT, was shown to degrade and inactivate the human antimicrobial peptide LL-37. This study aims to investigate the involvement of UPEC OmpT in LL-37 degradation. An ompT deletion mutant was generated in the prototypical UPEC strain CFT073. Western blot analysis showed that the OmpT protein level is moderate in CFT073. In agreement, OmpT was shown to partially cleave LL-37. However, no difference in the minimum inhibitory concentration of LL-37 was observed between CFT073 and the ompT mutant. Plasmid complementation of ompT, which led to increased OmpT levels, resulted in complete cleavage of LL-37 and a fourfold increase in the minimum inhibitory concentration. The analysis of other UPEC isolates showed similar OmpT activity levels as CFT073. Although UPEC OmpT can cleave LL-37, we conclude that the low level of OmpT limits its contribution to LL-37 resistance. Collectively, these data suggest that UPEC OmpT is likely accompanied by other LL-37 resistance mechanisms.

  16. The Escherichia coli BtuE protein functions as a resistance determinant against reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Felipe A Arenas

    Full Text Available This work shows that the recently described Escherichia coli BtuE peroxidase protects the bacterium against oxidative stress that is generated by tellurite and by other reactive oxygen species elicitors (ROS. Cells lacking btuE (ΔbtuE displayed higher sensitivity to K(2TeO(3 and other oxidative stress-generating agents than did the isogenic, parental, wild-type strain. They also exhibited increased levels of cytoplasmic reactive oxygen species, oxidized proteins, thiobarbituric acid reactive substances, and lipoperoxides. E. coli ΔbtuE that was exposed to tellurite or H(2O(2 did not show growth changes relative to wild type cells either in aerobic or anaerobic conditions. Nevertheless, the elimination of btuE from cells deficient in catalases/peroxidases (Hpx(- resulted in impaired growth and resistance to these toxicants only in aerobic conditions, suggesting that BtuE is involved in the defense against oxidative damage. Genetic complementation of E. coli ΔbtuE restored toxicant resistance to levels exhibited by the wild type strain. As expected, btuE overexpression resulted in decreased amounts of oxidative damage products as well as in lower transcriptional levels of the oxidative stress-induced genes ibpA, soxS and katG.

  17. Antimicrobial resistance and virulence factors in Escherichia coli from swedish dairy calves

    Directory of Open Access Journals (Sweden)

    de Verdier Kerstin

    2012-01-01

    Full Text Available Abstract Background In Sweden, knowledge about the role of enteropathogenic Escherichia coli in neonatal calf diarrhea and the occurrence of antimicrobial resistance in E. coli from young calves is largely unknown. This has therapeutic concern and such knowledge is also required for prudent use of antimicrobials. Methods In a case control study Esherichia coli isolated from faecal samples from dairy calves were phenotyped by biochemical fingerprinting and analyzed for virulence genes by PCR. Antimicrobial susceptibility was tested by determination of minimum inhibitory concentration (MIC. Farm management data were collected and Fisher's exact test and univariable and multivariable logistic regression analysis were performed. Results Of 95 E. coli tested for antimicrobial susceptibility 61% were resistant to one or more substances and 28% were multi-resistant. The virulence gene F5 (K99 was not found in any isolate. In total, 21 out of 40 of the investigated virulence genes were not detected or rarely detected. The virulence genes espP, irp, and fyuA were more common in resistant E. coli than in fully susceptible isolates (P terZ was associated with calf diarrhea (P ≤ 0.01. The participating 85 herds had a median herd size of 80 lactating cows. Herds with calf diarrhea problems were larger (> 55 cows; P P There was no association between calf diarrhea and diversity of enteric E. coli. Conclusions Antimicrobial resistance was common in E. coli from pre-weaned dairy calves, occurring particularly in calves from herds experiencing calf diarrhea problems. The results indicate that more factors than use of antimicrobials influence the epidemiology of resistant E. coli. Enteropathogenic E. coli seems to be an uncommon cause of neonatal calf diarrhea in Swedish dairy herds. In practice, calf diarrhea should be regarded holistically in a context of infectious agents, calf immunity, management practices etc. We therefore advice against routine

  18. Correlation between apramycin and gentamicin use in pigs and an increasing reservoir of gentamicin-resistant Escherichia coli

    DEFF Research Database (Denmark)

    Jensen, Vibeke Frøkjær; Jakobsen, Lotte; Emborg, Hanne-Dorthe;

    2006-01-01

    and gentamicin resistance in Escherichia coli strains from pork, healthy pigs and diagnostic submissions from pigs and to investigate potential relationships to the use of apramycin and gentamicin at farm and national levels. Methods: Data on Danish E. coli isolates from healthy pigs (indicator bacteria......-2004). The genetic background for gentamicin resistance was investigated by PCR. Relationships between antimicrobial usage and resistance were analysed by chi(2) test and logistic regression. Results: At the farm level, the occurrence of apramycin/gentamicin cross-resistance was correlated to the use of apramycin (P...... resistance in clinical E. coli 0149 isolates was significantly correlated with the amounts and duration of apramycin use. The aac(3)-IV gene was detected in all tested cross-resistant isolates. Conclusions: Apramycin consumption...

  19. Pathways of resistance to thymineless death in Escherichia coli and the function of UvrD.

    Science.gov (United States)

    Fonville, Natalie C; Vaksman, Zalman; DeNapoli, Jessica; Hastings, P J; Rosenberg, Susan M

    2011-09-01

    Thymineless death (TLD) is the rapid loss of viability in bacterial, yeast, and human cells starved of thymine. TLD is the mode of action of common anticancer drugs and some antibiotics. TLD in Escherichia coli is accompanied by blocked replication and chromosomal DNA loss and recent work identified activities of recombination protein RecA and the SOS DNA-damage response as causes of TLD. Here, we examine the basis of hypersensitivity to thymine deprivation (hyper-TLD) in mutants that lack the UvrD helicase, which opposes RecA action and participates in some DNA repair mechanisms, RecBCD exonuclease, which degrades double-stranded linear DNA and works with RecA in double-strand-break repair and SOS induction, and RuvABC Holliday-junction resolvase. We report that hyper-TLD in uvrD cells is partly RecA dependent and cannot be attributed to accumulation of intermediates in mismatch repair or nucleotide-excision repair. These data imply that both its known role in opposing RecA and an additional as-yet-unknown function of UvrD promote TLD resistance. The hyper-TLD of ruvABC cells requires RecA but not RecQ or RecJ. The hyper-TLD of recB cells requires neither RecA nor RecQ, implying that neither recombination nor SOS induction causes hyper-TLD in recB cells, and RecQ is not the sole source of double-strand ends (DSEs) during TLD, as previously proposed; models are suggested. These results define pathways by which cells resist TLD and suggest strategies for combating TLD resistance during chemotherapies. PMID:21705756

  20. 陕西部分地区不同食源性大肠杆菌耐药性检测%Drug Resistance Detection of Escherichia Coli from Different Food Origins in Some Districts of Shaanxi Province

    Institute of Scientific and Technical Information of China (English)

    只帅; 席美丽; 刘攻关; 吴淑鹏; 殷童; 姚远; 杨保伟; 孟江洪

    2011-01-01

    Antibiotic resistance and prevalence of Shiga Toxin-producing Escherichia coli were determined among Escherichia coli isolates collected from retail meats and ready-to-eat food in supermarkets and open markets in Xi'an and Yangling areas of Shaanxi Province. Antimicrobial Susceptibility to 15 antibiotics of 748 Escherichia coli isolates were determined by using agar dilution methods, which was recommended by National Committee of Clinical Laboratory Standard(NCCLS), and using E.coli. ATCC25922, E. faecalis ATCC29212, Staphylococcus Aureus ATCC25923 as quality control strains. The results indicated that the isolates were most resistant to streptomycin at 88.2%, followed by resistance to tetracycline (84.4%),trimethoprim-suffamethoxazole (64.4%), nalidixic acid (62.6%), ampicillin (56.0%),ciprofloxacin (39.2%), chloramphenicol (37.6%), kanamycin (34.9%), gentamicin (34.2% ), amoxicillin-clavulanic acid (28.9%),gatifloxacin(26.9%). The isolates displayed lower resistance to amikacin (8.3%), cefoxitin (11.5%), ceftriaxone(13.8%),cefoperazone (19.5%). 73.9% of the isolates were multidrug-resistant. Two Shiga Toxin-producing Escherichia coli isolates were isolated from pork and mutton samples. Escherichia coli isolates recovered from retail meats and ready-to-eat food in Xi'an district were seriously resistant to common antibiotics.%对陕西西安市和杨凌示范区超级市场及农贸市场零售内及凉拌菜中的大肠杆菌耐药性及肠产志贺样毒素大肠杆菌进行检测.采用美国临床实验室标准化委员会(National Committee of Clinical Laboratory Standard,NCCLS)推荐的琼脂稀释法,以大肠埃希氏菌ATCC25922、金黄色葡萄球菌ATCC25923及粪肠球菌ATCC29212为质控菌株,对来源于不同食品的748株大肠杆菌进行15种抗生素药敏性检测.发现大肠杆菌分离株对链霉素的抗性最高(88.2%),其次为四环素(84.4%)、甲氧苄啶-新诺明(644%)、萘啶酮酸(62.6%)

  1. Ciprofloxacin@SiO2: Fluorescent nanobubbles

    Indian Academy of Sciences (India)

    M J Rosemary; V Suryanarayanan; P Ganapati Reddy; Ian Maclaren; S Baskaran; T Pradeep

    2003-10-01

    We report a new nanomaterial in which ciprofloxacin molecules are incorporated inside silica nanobubbles, denoted as ciprofloxacin@SiO2. The material has been characterised using UV/Vis absorption spectroscopy, transmission electron microscopy, cyclic voltammetry, and emission spectroscopy. The material is stable and the freestanding particles can be precipitated and redispersed in several solvents. Confinement of the molecule is complete as leaching through the shell is minimal. The material behaves like free ciprofloxacin in solution; however, effects of confinement are manifested. Energy transfer reaction between ciprofloxacin@SiO2 and Tb3+ was monitored by emission spectroscopy. The emission intensity decreased with metal ion exposure indicating selective electronic interaction.

  2. Bilateral akillesseneruptur efter behandling med ciprofloxacin

    DEFF Research Database (Denmark)

    Attarzadeh, Amir Pasha; Ryge, Camilla

    2013-01-01

    We report a case of spontaneous non-traumatic bilateral rupture of the Achilles tendons following ciprofloxacin treatment. A 54-year-old man presented with spontaneous Achilles tendon rupture on the left side, tendinitis and partial tear on the right side following few days of treatment with...... ciprofloxacin 500 mg twice daily and long-term treatment with prednisolon 10 mg once daily. This rare side effect caused by concurrent treatment with steroids and ciprofloxacin should be kept in mind. Any signs of tendinitis following this treatment should arouse the physicians' suspicion towards ciprofloxacin....

  3. Induction of bacterial antibiotic resistance by mutagenic halogenated nitrogenous disinfection byproducts

    International Nuclear Information System (INIS)

    Halogenated nitrogenous disinfection byproducts (N-DBPs) raise concerns regarding their mutagenicity and carcinogenicity threatening public health. However, environmental consequence of their mutagenicity has received less attention. In this study, the effect of halogenated N-DBPs on bacterial antibiotic resistance (BAR) was investigated. After exposure to bromoacetamide (BAcAm), trichloroacetonitrile (TCAN) or tribromonitromethane (TBNM), the resistance of Pseudomonas aeruginosa PAO1 to both individual and multiple antibiotics (ciprofloxacin, gentamicin, polymyxin B, rifampin, tetracycline, ciprofloxacin + gentamicin and ciprofloxacin + tetracycline) was increased, which was predominantly ascribed to the overexpression of efflux pumps. The mechanism of this effect was demonstrated to be mutagenesis through sequencing and analyzing antibiotic resistance genes. The same induction phenomena also appeared in Escherichia coli, suggesting this effect may be universal to waterborne pathogens. Therefore, more attention should be given to halogenated N-DBPs, as they could increase not only genotoxicological risks but also epidemiological risks of drinking water. - Highlights: • The halogenated N-DBPs could induce bacterial antibiotic resistance. • Both individual and multiple resistances could be induced. • Efflux mechanism played an important role in the induced antibiotic resistance. • The halogenated N-DBPs induced bacterial antibiotic resistance via mutagenesis. • Effects of N-DBPs on antibiotic resistance may be universal to waterborne pathogens. - Halogenated N-DBPs could increase antibiotic resistance, even multidrug resistance via mutagenesis, contributing to the enrichment of antibiotic resistant bacteria in drinking water

  4. Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human

    DEFF Research Database (Denmark)

    Shuyu, Wu; Dalsgaard, A.; Hammerum, A. M.;

    2010-01-01

    Background Sulfonamide resistance is very common in Escherichia coli. The aim of this study was to characterize plasmids carrying sulfonamide resistance genes (sul1, sul2 and sul3) in E. coli isolated from pigs and humans with a specific objective to assess the genetic diversity of plasmids...... involved in the mobility of sul genes. Methods A total of 501 E. coli isolates from pig feces, pig carcasses and human stools were tested for their susceptibility to selected antimicrobial. Multiplex PCR was conducted to detect the presence of three sul genes among the sulfonamide-resistant E. coli...... isolates. Fifty-seven sulfonamide-resistant E. coli were selected based on presence of sul resistance genes and subjected to conjugation and/or transformation experiments. S1 nuclease digestion followed by pulsed-field gel electrophoresis was used to visualize and determine the size of plasmids. Plasmids...

  5. Mecanismos moleculares de resistencia antibiótica en Escherichia coli asociadas a diarrea Molecular mechanisms of antibiotic resistance in Escherichia coli- associated diarrhea

    Directory of Open Access Journals (Sweden)

    Susan Mosquito

    2011-12-01

    Full Text Available La resistencia antibiótica es un problema emergente a nivel mundial presente en diversas bacterias, en especial en la Escherichia coli, que tiene altos porcentajes de resistencia hacia ampicilina, trimetoprim-sulfametoxazol, tetraciclina, cloramfenicol y ácido nalidíxico, lo que supone grandes complicaciones en el tratamiento antibiótico cuando este es requerido. Este aumento de resistencia antibiótica se debe a la adquisición de diferentes mecanismos moleculares de resistencia mediante mutaciones puntuales a nivel cromosómico o transferencia horizontal de material genético entre especies relacionadas o diferentes, facilitada por algunos elementos genéticos tales como los integrones. Esta revisión discute los efectos de los mecanismos moleculares de resistencia más comunes en E.coli: inactivación enzimática, alteraciones en el sitio blanco y alteraciones de la permeabilidad. El conocer los mecanismos de resistencia implicados, como lo recomienda la Organización Mundial de la Salud, permitirá optimizar la vigilancia de resistencia y las políticas de control y uso de antibióticos a nivel nacional.Antibiotic resistance is an emerging problem worldwide present in many bacteria, specially in Escherichia coli, which has high percentages of resistance to ampicilline, thrimethoprim-sulfamethoxazole, tetracycline, chloramphenicol and nalidixic acid, which implies important complications in antibiotic treatment when required. The increasing antibiotic resistance is due to the acquisition of different molecular mechanisms of resistance through point chromosomal mutations and /or horizontal transfer of genetic material between related or different species facilitated by some genetic elements such as integrons. This review discusses the effects of the most common molecular mechanisms of antibiotic resistance in E. coli: enzymatic inactivation, changes in the target site and permeability disturbances. Getting to know the mechanisms of

  6. Recent Sensitivity Pattern of Escherichia Coli in Urinary Tract Infection

    Directory of Open Access Journals (Sweden)

    R Nalini

    2014-06-01

    Full Text Available The objective of the study is to assess the recent sensitivity pattern of Escherichia coli in Urinary tract infection (UTI.Widespread use of antibiotics has led to the emergence of resistant microorganisms. As the antibiotic sensitivity patterns of the microorganisms are frequently changing, this retrospective analysis was designed to assess the recent antibiotic sensitivity pattern of Escherichia coli (E.coli in urinary tract infection among the human population. Details of 412 urine culture positive reports for E.coli and their antibiotic sensitivity pattern pertaining to the study period of 12months from June 2012 to May 2013 were collected from Central Microbiology Laboratory of Tirunelveli Medical College and the results were statistically analysed. The antibiotics tested for sensitivity were Amikacin, Gentamycin, Ciprofloxacin, Cotrimoxazole, Nitrofurantoin, Ceftazidime, Ceftriaxone and Cefotaxime. The sensitivity pattern of E.coli to antibiotics in UTI were Nitrofurantoin (85.19%, Amikacin (66.50%, Co-trimoxazole(31.31%, Gentamycin (26.90%, Ceftazidime (26.69% ,Ciprofloxacin (22.57%, Cefotaxime (22.30%, Ceftriaxone (17.47%. The study highlighted the re-emergence of E. coli sensitive to Nitrofurantoin and marked resistance of E.coli to Aminoglycoside and third generation Cephalosporins.

  7. Environmental fluctuations do not select for increased variation or population-based resistance in Escherichia coli

    Indian Academy of Sciences (India)

    Shraddha Madhav Karve; Kanishka Tiwary; S Selveshwari; Sutirth Dey

    2016-03-01

    Little is known about the mechanisms that enable organisms to cope with unpredictable environments. To address this issue, we used replicate populations of Escherichia coli selected under complex, randomly changing environments. Under four novel stresses that had no known correlation with the selection environments, individual cells of the selected populations had significantly lower lag and greater yield compared to the controls. More importantly, there were no outliers in terms of growth, thus ruling out the evolution of population-based resistance. We also assayed the standing phenotypic variation of the selected populations, in terms of their growth on 94 different substrates. Contrary to expectations, there was no increase in the standing variation of the selected populations, nor was there any significant divergence from the ancestors. This suggested that the greater fitness in novel environments is brought about by selection at the level of the individuals, which restricts the suite of traits that can potentially evolve through this mechanism. Given that day-to-day climatic variability of the world is rising, these results have potential public health implications. Our results also underline the need for a very different kind of theoretical approach to study the effects of fluctuating environments.

  8. Environmental fluctuations do not select for increased variation or population-based resistance in Escherichia coli.

    Science.gov (United States)

    Karve, Shraddha Madhav; Tiwary, Kanishka; Selveshwari, S; Dey, Sutirth

    2016-03-01

    Little is known about the mechanisms that enable organisms to cope with unpredictable environments. To address this issue, we used replicate populations of Escherichia coli selected under complex, randomly changing environments. Under four novel stresses that had no known correlation with the selection environments, individual cells of the selected populations had significantly lower lag and greater yield compared to the controls. More importantly, there were no outliers in terms of growth, thus ruling out the evolution of population-based resistance. We also assayed the standing phenotypic variation of the selected populations, in terms of their growth on 94 different substrates. Contrary to expectations, there was no increase in the standing variation of the selected populations, nor was there any significant divergence from the ancestors. This suggested that the greater fitness in novel environments is brought about by selection at the level of the individuals, which restricts the suite of traits that can potentially evolve through this mechanism. Given that day-to-day climatic variability of the world is rising, these results have potential public health implications. Our results also underline the need for a very different kind of theoretical approach to study the effects of fluctuating environments. PMID:26949086

  9. Bactericidal activity of Musca domestica cecropin (Mdc) on multidrug-resistant clinical isolate of Escherichia coli.

    Science.gov (United States)

    Lu, X; Shen, J; Jin, X; Ma, Y; Huang, Y; Mei, H; Chu, F; Zhu, J

    2012-08-01

    The housefly (Musca domestica) larvae have been used clinically to cure osteomyelitis, decubital necrosis, lip boil, ecthyma and malnutritional stagnation ever since the Ming/Qing Dynasty (1368 Anno Domini) till now, in China. In prior research, we have cloned and characterized a new gene of antimicrobial peptide cecropin from M. domestica larvae. This peptide was potently active against Gram-positive and Gram-negative bacteria standard strain. In the present study, we evaluated the possibility of Mdc to be a potential bactericidal agent against clinical isolates of multidrug-resistant (MDR) Escherichia coli and to elucidate the related antimicrobial mechanisms. Antimicrobial activity assays indicated a minimal inhibitory concentration (MIC) of 1.56 μM. Bactericidal kinetics at MIC showed that Mdc rapid killing of MDR E. coli. Lipopolysaccharide (LPS) dose-dependently suppressed Mdc antibacterial potency indicates that LPS is the initial binding site of Mdc in E. coli. Propidium iodide-based flow cytometry revealed that Mdc causes E. coli membrane permeabilization. Transmission electron micrographs further indicated that a remarkable damage in the bacteria's outer and inner membrane, even the leakage of cytoplasmic contents induced by Mdc. DNA binding experimental result implies that DNA is one of the possible intracellular targets of Mdc. Of note, Mdc did not show a perceptible cytotoxic effect on human red blood cells. Altogether, these results suggest that Mdc could be an excellent candidate for the development of more efficacious bactericidal agents. PMID:22202966

  10. Antimicrobial resistance trends among canine Escherichia coli isolates obtained from clinical samples in the northeastern USA, 2004–2011

    OpenAIRE

    Cummings, Kevin J.; Aprea, Victor A.; Altier, Craig

    2015-01-01

    Our objectives were to describe the antimicrobial susceptibility of Escherichia coli isolates from dogs in the northeastern USA and to identify temporal trends in resistance to selected antimicrobial agents. Data were collected retrospectively for all canine E. coli isolates from clinical samples submitted to Cornell University’s Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Antimicrobial susceptibility testing was performed on 3519 canine E. coli isolates; fr...

  11. Low minimum inhibitory concentrations associated with the tetracycline-resistance gene tet(C) in Escherichia coli

    OpenAIRE

    Chalmers, Gabhan; Kozak, Gosia K.; Hillyer, Elizabeth; Reid-Smith, Richard J.; Boerlin, Patrick

    2010-01-01

    Twenty-eight Escherichia coli isolates from various animal and environmental sources with defined tetracycline-resistance genotypes for tet(A), tet(B), and tet(C) were tested for their susceptibility to tetracycline by means of both broth microdilution and Etest. All tet(C)-positive isolates had tetracycline minimum inhibitory concentrations clustering around an intermediate susceptibility range of 2 to 16 μg/mL. Detecting tet(C)-positive isolates by means of susceptibility testing may theref...

  12. The BaeSR Two-Component Regulatory System Mediates Resistance to Condensed Tannins in Escherichia coli▿ †

    OpenAIRE

    Zoetendal, E.G.; Smith, A H; Sundset, M.A.; Mackie, R. I.

    2007-01-01

    The gene expression profiles of Escherichia coli strains grown anaerobically with or without Acacia mearnsii (black wattle) extract were compared to identify tannin resistance strategies. The cell envelope stress protein gene spy and the multidrug transporter-encoding operon mdtABCD, both under the control of the BaeSR two-component regulatory system, were significantly up-regulated in the presence of tannins. BaeSR mutants were more tannin sensitive than their wild-type counterparts.

  13. Antimicrobial Resistance, Virulence Factors and Genetic Diversity of Escherichia coli Isolates from Household Water Supply in Dhaka, Bangladesh

    OpenAIRE

    Talukdar, Prabhat Kumar; Rahman, M; Nabi, Ashikun; Islam, Zhahirul; Hoque, Mahfuzul; Endtz, Hubert

    2013-01-01

    textabstractBackground: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. Methodology/Principal Findings: A total of 233 E. coli isolate...

  14. High Prevalence of Class 1 to 3 Integrons Among Multidrug-Resistant Diarrheagenic Escherichia coli in Southwest of Iran

    OpenAIRE

    Kargar, Mohammad; Mohammadalipour, Zahra; Doosti, Abbas; Lorzadeh, Shahrokh; Japoni-Nejad, Alireza

    2014-01-01

    Objectives Horizontal transfer of integrons is one of the important factors that can contribute to the occurrence of multidrug-resistant (MDR) bacteria. This study aimed to determine the prevalence of integrons among MDR Escherichia coli strains isolated from stool specimens and investigate the associations between the existence of integrons and MDR properties in the southwest of Iran. Methods There were 164 E. coli strains isolated from January 2012 to June 2012. Fecal specimens identified a...

  15. Risk Factors for the Development of Gastrointestinal Colonization With Fluoroquinolone-Resistant Escherichia coli in Residents of Long-Term Care Facilities

    OpenAIRE

    Han, Jennifer H.; Maslow, Joel; Han, Xiaoyan; Xie, Sharon X; Tolomeo, Pam; Santana, Evelyn; Carson, Lesley; Lautenbach, Ebbing

    2013-01-01

    Background. The objective of this study was to assess risk factors for the development of fluoroquinolone (FQ)–resistant Escherichia coli gastrointestinal tract colonization in long-term care facility (LTCF) residents.

  16. Antimicrobial Susceptibility and Molecular Mechanisms of Fosfomycin Resistance in Clinical Escherichia coli Isolates in Mainland China.

    Directory of Open Access Journals (Sweden)

    Ya Li

    Full Text Available Escherichia coli is one of the most common pathogens in nosocomial and community-acquired infections in humans. Fosfomycin is a broad-spectrum antibiotic which inhibits peptidoglycan synthesis responsible for bacterial cell wall formation. Although low, the exact E. coli susceptibility to fosfomycin as well as the mechanisms of resistance in the population from Mainland China are mostly unknown. 1109 non-duplicate clinical E. coli strains isolated from urine, sputum, blood and pus samples in 20 widely dispersed tertiary hospitals from Mainland China were collected from July 2009 to June 2010, followed by determination of minimum inhibitory concentrations of fosfomycin. Detection of the murA, glpT, uhpT, fosA, fosA3 and fosC genes was performed in fosfomycin non-susceptible E. coli strains and conjugation experiments were employed to determine the mobility of fosA3 gene. In this study, 7.8% (86/1109 E. coli strains were fosfomycin non-susceptible. Amino acid substitutions in GlpT and MurA were found in six and four E.coli strains, respectively, while the uhpT gene was absent in eighteen E.coli strains. Twenty-nine isolates carried the transferable plasmid with the fosA3 gene at high frequencies of around 10(-6 to 10(-7 per donor cell in broth mating. The majority of isolates were susceptible to fosfomycin, showing that the drug is still viable in clinical applications. Also, the main mechanism of E. coli resistance in Mainland China was found to be due to the presence of the fosA3 gene.

  17. Antimicrobial resistance in indicator Escherichia coli isolates from free-ranging livestock and sympatric wild ungulates in a natural environment (Northeastern Spain).

    Science.gov (United States)

    Navarro-Gonzalez, N; Porrero, M C; Mentaberre, G; Serrano, E; Mateos, A; Domínguez, L; Lavín, S

    2013-10-01

    Antimicrobial resistance was assessed in indicator Escherichia coli isolates from free-ranging livestock and sympatric wild boar (Sus scrofa) and Iberian ibex (Capra pyrenaica) in a National Game Reserve in northeastern Spain. The frequency of antimicrobial resistance was low (0% to 7.9%). However, resistance to an extended-spectrum cephalosporin and fluoroquinolones was detected.

  18. Investigation of carbon storage regulation network (csr genes) and phenotypic differences between acid sensitive and resistant Escherichia coli O157:H7 strains

    Science.gov (United States)

    Background: Escherichia coli O157:H7 and related serotype strains have previously been shown to vary in acid resistance, however, little is known about strain specific mechanisms of acid resistance. We examined sensitive and resistant E. coli strains to determine the effects of growth in minimal and...

  19. Impairment of ciprofloxacin absorption by calcium polycarbophil.

    Science.gov (United States)

    Kato, Ryuji; Ueno, Kazuyuki; Imano, Hideki; Kawai, Masayuki; Kuwahara, Shiro; Tsuchishita, Yoshimasa; Yonezawa, Emi; Tanaka, Kazuhiko

    2002-07-01

    The effect of calcium polycarbophil on the absorption of ciprofloxacin, a broad-spectrum antibacterial agent, was evaluated in an in vitro and in vivo study. In the in vitro study, the release of ciprofloxacin from the cellulose membrane in the presence or absence of metal cations was measured using the dissolution test procedure. In the in vivo study, male ST Wistar rats and male volunteers were employed. First, 20 mg/kg of ciprofloxacin alone (Rat Study 1) or 20 mg/kg of ciprofloxacin in combination with 64 mg/kg of calcium chloride (Rat Study 2) was administered orally to 3 rats. Second, a volunteer study was employed and a randomized crossover design with twophases was used. In onephase, volunteers received 400 mg of ciprofloxacin alone (Study 1); in the other phase, they received 400 mg of ciprofloxacin and 1200 mg of fine calcium polycarbophil granules concomitantly (Study 2). The plasma and serum concentrations of ciprofloxacin were measured by high-performance liquid chromatography. The release of ciprofloxacin from the cellulose membrane in the presence of aluminum, calcium, or iron ions was slower than that in the absence of these metal ions. The AUC0-4 and Cmax in Rat Study 2 were lower than those respective values in Rat Study 1. AUC0-4 was approximately 60% lower in Rat Study 2 than Rat Study 1. In the volunteer study, the AUC0-12 and Cmax in Study 2 were lower than those respective values in Study 1. In particular, AUC0-12 was approximately 50% lowerin Study 2 than in Study 1. These findings suggest that when ciprofloxacin and calcium polycarbophil were coadministered concomitantly, a decrease of ciprofloxacin absorption was observed, and this action was caused by the formation of chelate complexes. Therefore, it seems clear that we should avoid the concomitant administration of ciprofloxacin and calcium polycarbophil.

  20. Investigation of integrons/cassettes in antimicrobial-resistant Escherichia coli isolated from food animals in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of E.coli has increased since the 1970s.The findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in China.

  1. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    The genetic background for beta-lactamase-mediated resistance to beta-lactam antibiotics was examined by PCR and sequencing in 160 ampicillin-resistant isolates (109 Escherichia coli and 51 Salmonella) obtained from healthy and diseased food animals in Denmark. Sequencing revealed three different...... new variants of bla(TEM) were detected, which have been designated bla(TEM-127) and bla(TEM-128.) In TEM-127, amino acid 158 is substituted from His to Asn, whereas a substitution from Asp to Glu is seen at amino acid 157 in TEM-128. According to MIC determinations, these novel enzymes do not possess...

  2. Susceptibility of Pseudomonas isolates from the ears and skin of dogs to enrofloxacin, marbofloxacin, and ciprofloxacin.

    Science.gov (United States)

    Wildermuth, Brett Everett; Griffin, Craig E; Rosenkrantz, Wayne S; Boord, Mona J

    2007-01-01

    The purpose of this study was to compare susceptibilities of ear and skin Pseudomonas spp. isolates to enrofloxacin, marbofloxacin, and ciprofloxacin. Specimens were obtained from dogs examined in a veterinary dermatology referral hospital. Susceptibilities of ear isolates to enrofloxacin, marbofloxacin, and ciprofloxacin were 46.9%, 66.7%, and 75.0%, respectively. Susceptibilities of skin isolates to the same drugs were 76.2%, 81.0%, and 80.0%, respectively. Ear isolates were significantly less susceptible to enrofloxacin than to ciprofloxacin (P=0.021), and ear isolates were significantly less susceptible to enrofloxacin than were skin isolates (P=0.034). When fluoroquinolone resistance was present, ear isolates were significantly less susceptible to enrofloxacin than to ciprofloxacin (Pmarbofloxacin (P=0.014).

  3. Ciprofloxacin non-susceptible Streptococcus pyogenes due to mutations in parC gene and its homology analysis

    Institute of Scientific and Technical Information of China (English)

    张晓飞

    2013-01-01

    Objective To investigate the resistant mechanism of Streptococcus pyogenes to ciprofloxacin and its homology.Methods Forty-eight isolates of Streptococcus pyogenes were collected from patients diagnosed with scarflet fever

  4. Ciprofloxacin

    Science.gov (United States)

    ... are taking antacids containing aluminum hydroxide or magnesium hydroxide (Maalox, Mylanta, Tums, others); didanosine (Videx); calcium, iron, zinc, or vitamin supplements; or sucralfate (Carafate), you ...

  5. Comparative activity of ciprofloxacin against anaerobic bacteria.

    OpenAIRE

    Sutter, V L; Kwok, Y Y; Bulkacz, J

    1985-01-01

    The in vitro activity of ciprofloxacin was assessed against 362 strains of anaerobic bacteria and compared with that of cefoxitin, clindamycin, metronidazole, and mezlocillin. Only 31% of the strains tested were susceptible to ciprofloxacin. The other agents were active against most of the strains tested.

  6. Ciprofloxacin therapy for Mediterranean spotted fever.

    OpenAIRE

    Raoult, D.; Gallais, H.; De Micco, P; Casanova, P

    1986-01-01

    We report the treatment of five patients with Mediterranean spotted fever with the antimicrobial agent ciprofloxacin. The treatment was administered intravenously for 2 days and then perorally for 8 days. All five patients were cured. These preliminary data seem to correlate with the in vitro activity of ciprofloxacin against Rickettsia conorii.

  7. Effect of bacteriophage infection in combination with tobramycin on the emergence of resistance in Escherichia coli and Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Coulter, Lindsey B; McLean, Robert J C; Rohde, Rodney E; Aron, Gary M

    2014-10-03

    Bacteriophage infection and antibiotics used individually to reduce biofilm mass often result in the emergence of significant levels of phage and antibiotic resistant cells. In contrast, combination therapy in Escherichia coli biofilms employing T4 phage and tobramycin resulted in greater than 99% and 39% reduction in antibiotic and phage resistant cells, respectively. In P. aeruginosa biofilms, combination therapy resulted in a 60% and 99% reduction in antibiotic and PB-1 phage resistant cells, respectively. Although the combined treatment resulted in greater reduction of E. coli CFUs compared to the use of antibiotic alone, infection of P. aeruginosa biofilms with PB-1 in the presence of tobramycin was only as effective in the reduction of CFUs as the use of antibiotic alone. The study demonstrated phage infection in combination with tobramycin can significantly reduce the emergence of antibiotic and phage resistant cells in both E. coli and P. aeruginosa biofilms, however, a reduction in biomass was dependent on the phage-host system.

  8. Persistence of Escherichia coli clones and phenotypic and genotypic antibiotic resistance in recurrent urinary tract infections in childhood

    DEFF Research Database (Denmark)

    Kõljalg, Siiri; Truusalu, Kai; Vainumäe, Inga;

    2009-01-01

    We assessed the clonality of consecutive Escherichia coli isolates during the course of recurrent urinary tract infections (RUTI) in childhood in order to compare clonality with phenotypic antibiotic resistance patterns, the presence of integrons, and the presence of the sul1, sul2, and sul3 genes...... and the presence or absence of the intI gene for class 1 integrons and the sulfamethoxazole resistance-encoding genes sul1, sul2, and sul3 were determined. All E. coli strains were genotyped by pulsed-field gel electrophoresis. There were no significant differences in the prevalences of resistance to beta......% of the patients, the recurrence of unique clonal E. coli strains alone or combined with individual strains was detected. Phenotypic resistance and the occurrence of sul genes were more stable in clonal strains than in individual strains (odds ratios, 8.7 [95% confidence interval {95% CI}, 1.8 to 40.8] and 4.4 [95...

  9. Antimicrobial effects of Lactobacillus plantarum and Lactobacillus acidophilus against multidrug-resistant enteroaggregative Escherichia coli.

    Science.gov (United States)

    Kumar, Manesh; Dhaka, Pankaj; Vijay, Deepthi; Vergis, Jess; Mohan, Vysakh; Kumar, Ashok; Kurkure, Nitin V; Barbuddhe, Sukhadeo B; Malik, S V S; Rawool, Deepak B

    2016-09-01

    The in vitro and in vivo antimicrobial effects of Lactobacillus plantarum and Lactobacillus acidophilus were evaluated individually and synergistically against multidrug-resistant enteroaggregative Escherichia coli (MDR-EAEC). In vitro evaluation of each probiotic strain when co-cultured with MDR-EAEC isolates revealed a reduction in MDR-EAEC counts (eosin-methylene blue agar) in a dose- and time-dependent manner: probiotics at a dose rate of 10(10) CFU inhibited MDR-EAEC isolates at 72 h post-inoculation (PI), whereas at lower concentrations (10(8) and 10(9) CFU) MDR-EAEC isolates were inhibited at 96 h PI. The synergistic antimicrobial effect of both probiotic strains (each at 10(10) CFU) was highly significant (P < 0.01) and inhibited the growth of MDR-EAEC isolates at 24 h PI. For in vivo evaluation, weaned mice were fed orally with 10(7) CFU of MDR-EAEC. At Day 3 post-infection, treated mice were fed orally with the probiotic strains (each at 10(10) CFU). Compared with the control, post-treatment a significant (P < 0.01) reduction in MDR-EAEC counts was observed in faeces by Day 2 and in intestinal tissues of treated mice by Days 3 and 4 as evidenced by plate count (mean 2.71 log and 2.27 log, respectively) and real-time PCR (mean 1.62 log and 1.57 log, respectively) methods. Histopathologically, comparatively mild changes were observed in the ileum and colon from Days 3 to 5 post-treatment with probiotics; however, from Day 6 the changes were regenerative or normal. These observations suggest that these probiotic strains can serve as alternative therapeutics against MDR-EAEC-associated infections in humans and animals. PMID:27451088

  10. Exposure to co-amoxiclav as a risk factor for co-amoxiclav-resistant Escherichia coli urinary tract infection.

    Science.gov (United States)

    Leflon-Guibout, Véronique; Ternat, Géraldine; Heym, Beate; Nicolas-Chanoine, Marie-Hélène

    2002-02-01

    The objective of the study was to define whether individual exposure to co-amoxiclav is a risk factor for selecting co-amoxiclav-resistant Escherichia coli in vivo. One hundred and eight patients were included in our study as soon as they were found to have a urinary tract infection (UTI) due to E. coli. Stool probes were also undertaken for some of these patients. Co-amoxiclav administration in the month before diagnosing the UTI, and any treatment to cure the current UTI were recorded for all patients. When co-amoxiclav-resistant E. coli was detected in the stools after diagnosis of E. coli UTI, isolates were compared with urinary E. coli isolates in terms of clonal relatedness, beta-lactam susceptibility and mechanisms of beta-lactam resistance. The patients who had taken co-amoxiclav in the month before the reported E. coli UTI had a significantly higher risk of being infected with co-amoxiclav-resistant E. coli. Those patients treated with amoxicillin for a current infection were at greater risk of intestinal carriage of co-amoxiclav-resistant E. coli; those treated with co-amoxiclav had a greater risk of intestinal carriage of co-amoxiclav-resistant Gram-negative bacilli than patients treated with third-generation cephalosporins or fluoroquinolones. Hence, individual exposure to co-amoxiclav is a risk factor for UTIs caused by co-amoxiclav-resistant E. coli or for carrying co-amoxiclav-resistant Gram-negative bacilli in the digestive tract.

  11. CHARACTERIZATION OF VIRULENCE GENES AND ANTIMICROBIAL RESISTANCE OF LUNG PATHOGENIC ESCHERICHIA COLI ISOLATES IN FOREST MUSK DEER (MOSCHUS BEREZOVSKII).

    Science.gov (United States)

    Luo, Xi; Wang, Peng; Cheng, Jian-guo; Luo, Yan; Dai, Lei; Zhou, Xin; Zou, Li-kou; Li, Bei; Xiao, Jiu-Jin

    2016-06-01

    This study investigated genotypic diversity, 26 virulence genes, and antimicrobial susceptibility of lung pathogenic Escherichia coli (LPEC) isolated from forest musk deer. Associations between virulence factors (VFs) and phylogenetic group, between antimicrobial resistance (AMR) and phylogenetic group, and between AMR and VFs were subsequently assessed. The results showed 30 LPEC isolated were grouped into seven different clusters (A, B, C, D, E, F, and G). The detection rates of crl (90%), kpsMT II (76.67%), mat (76.67%), and ompA (80%) were over 75%. The most frequent types of resistance were to amoxicillin (100%), sulfafurazole (100%), ampicillin (96.67%), and tetracycline (96.67%), with 93.33% (n = 28) of isolates resistant to more than eight types of drugs. There were significant relationships between resistance to cefalotin and the presence of iucD(a) (P < 0.001), papC (P = 0.032), and kpsMT II (P = 0.028); between resistance to chloromycetin and the presence of irp2 (P = 0.004) and vat (P = 0.047); between resistance to nalidixic acid and the presence of crl (P = 0.002) and iucD(a) (P = 0.004); and between resistance to ampicillin/sulbactam and the presence of vat (P = 0.013). These results indicated there could be some association between resistance and VFs, and there is a great need for the prudent use of antimicrobial agents in LPEC.

  12. CHARACTERIZATION OF VIRULENCE GENES AND ANTIMICROBIAL RESISTANCE OF LUNG PATHOGENIC ESCHERICHIA COLI ISOLATES IN FOREST MUSK DEER (MOSCHUS BEREZOVSKII).

    Science.gov (United States)

    Luo, Xi; Wang, Peng; Cheng, Jian-guo; Luo, Yan; Dai, Lei; Zhou, Xin; Zou, Li-kou; Li, Bei; Xiao, Jiu-Jin

    2016-06-01

    This study investigated genotypic diversity, 26 virulence genes, and antimicrobial susceptibility of lung pathogenic Escherichia coli (LPEC) isolated from forest musk deer. Associations between virulence factors (VFs) and phylogenetic group, between antimicrobial resistance (AMR) and phylogenetic group, and between AMR and VFs were subsequently assessed. The results showed 30 LPEC isolated were grouped into seven different clusters (A, B, C, D, E, F, and G). The detection rates of crl (90%), kpsMT II (76.67%), mat (76.67%), and ompA (80%) were over 75%. The most frequent types of resistance were to amoxicillin (100%), sulfafurazole (100%), ampicillin (96.67%), and tetracycline (96.67%), with 93.33% (n = 28) of isolates resistant to more than eight types of drugs. There were significant relationships between resistance to cefalotin and the presence of iucD(a) (P < 0.001), papC (P = 0.032), and kpsMT II (P = 0.028); between resistance to chloromycetin and the presence of irp2 (P = 0.004) and vat (P = 0.047); between resistance to nalidixic acid and the presence of crl (P = 0.002) and iucD(a) (P = 0.004); and between resistance to ampicillin/sulbactam and the presence of vat (P = 0.013). These results indicated there could be some association between resistance and VFs, and there is a great need for the prudent use of antimicrobial agents in LPEC. PMID:27468027

  13. Antimicrobial Susceptibility Testing for Escherichia coli Strains to Fluoroquinolones, in Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    FA Nakhjavani

    2007-05-01

    Full Text Available Background: Urinary Tract Infections (UTIs are one of the most common infectious diseases diagnosed all over the world. Meanwhile most episode of UTIs are caused by Escherichia coli (up to 85% and frequently fluoroquinolones are preferred as initial agents for empiric therapy of UTIs. Widespread use of fluoroquinolones has resulted in an increasing incidence of resistance these agents all over the world. The aim of this study was to assess, susceptibility of Escherichia coli strains from UTI patients against common fluoroquinolones. Methods: Antimicrobial susceptibility testing was determined by disk agar diffusion (DAD and Minimal Inhibitory Concentration methods as described by the National Committee for Clinical Laboratory Standards (NCCLS. Results: One hundred sixty four clinical isolates of E. coli were collected by urine cultures from patients with UTI. The extent of resistant to nalidixic acid, ofloxacin, norfloxacin and ciprofloxacin, by disk diffusion method was 49.3%, 44.5%, 41.4% and 40.2%, respectively. Resistance to ciprofloxacin by MIC method was 4.9%. Conclusion: This study represents high level resistant of E. coli isolates from UTI patients. It is because of inappropriate and incorrect administration of antimicrobial agents in blind cases. This problem remarks significance of performing antimicrobial susceptibility testing before empiric antibiotic therapy. To overcome this problem use of unnecessary antibiotics therapy should be limited.

  14. Antimicrobial Resistance in Generic Escherichia coli Isolates from Wild Small Mammals Living in Swine Farm, Residential, Landfill, and Natural Environments in Southern Ontario, Canada▿

    OpenAIRE

    Allen, Samantha E.; Boerlin, Patrick; Janecko, Nicol; Lumsden, John S; Barker, Ian K; Pearl, David L; Reid-Smith, Richard J.; Jardine, Claire

    2010-01-01

    To assess the impacts of different types of human activity on the development of resistant bacteria in the feces of wild small mammals, we compared the prevalences and patterns of antimicrobial resistance and resistance genes in generic Escherichia coli and Salmonella enterica isolates from fecal samples collected from wild small mammals living in four environments: swine farms, residential areas, landfills, and natural habitats. Resistance to antimicrobials was observed in E. coli isolates f...

  15. Amodiaquine and Ciprofloxacin Combination in Plasmodiasis Therapy

    Directory of Open Access Journals (Sweden)

    Peace Mayen Edwin Ubulom

    2015-01-01

    Full Text Available Objective. The study was designed to determine the efficacy of combined Amodiaquine and Ciprofloxacin in plasmodiasis therapy. Method. The in vivo antiplasmodial effect of different dosage levels of Amodiaquine, Ciprofloxacin, and their combinations against Plasmodium berghei berghei was evaluated using Swiss albino mice. Results. Amodiaquine (a known antiplasmodial agent had a fairly significant antiplasmodial effect reducing the parasites for every 100 red blood cells (RBC from 66 to 16 (75.75% at the tolerable dosage level of 7.5 mg/kg body weight while Ciprofloxacin (an antibiotic known to have antimalarial effect showed an insignificant antiplasmodial effect reducing the parasites for every 100 RBC from 65 to 64 (1.53% at the tolerable dosage level of 10.7 mg/kg body weight. Conversely, the combination therapy of Amodiaquine and Ciprofloxacin had a significant antiplasmodial effect at all the doses administered. The combination of 7.5 mg/kg of Amodiaquine and 12.8 mg/kg of Ciprofloxacin, however, showed the most significant antiplasmodial effect of the doses used reducing the number of parasites per 100 RBC from 60 to 10 (83.33%. Conclusions. Appropriate Amodiaquine and Ciprofloxacin combination will be effective for the treatment of malaria and better than either Amodiaquine or Ciprofloxacin singly at their recommended dosage levels.

  16. Amodiaquine and Ciprofloxacin Combination in Plasmodiasis Therapy.

    Science.gov (United States)

    Ubulom, Peace Mayen Edwin; Udobi, Chinweizu Ejikeme; Madu, Mark Iheukwumere

    2015-01-01

    Objective. The study was designed to determine the efficacy of combined Amodiaquine and Ciprofloxacin in plasmodiasis therapy. Method. The in vivo antiplasmodial effect of different dosage levels of Amodiaquine, Ciprofloxacin, and their combinations against Plasmodium berghei berghei was evaluated using Swiss albino mice. Results. Amodiaquine (a known antiplasmodial agent) had a fairly significant antiplasmodial effect reducing the parasites for every 100 red blood cells (RBC) from 66 to 16 (75.75%) at the tolerable dosage level of 7.5 mg/kg body weight while Ciprofloxacin (an antibiotic known to have antimalarial effect) showed an insignificant antiplasmodial effect reducing the parasites for every 100 RBC from 65 to 64 (1.53%) at the tolerable dosage level of 10.7 mg/kg body weight. Conversely, the combination therapy of Amodiaquine and Ciprofloxacin had a significant antiplasmodial effect at all the doses administered. The combination of 7.5 mg/kg of Amodiaquine and 12.8 mg/kg of Ciprofloxacin, however, showed the most significant antiplasmodial effect of the doses used reducing the number of parasites per 100 RBC from 60 to 10 (83.33%). Conclusions. Appropriate Amodiaquine and Ciprofloxacin combination will be effective for the treatment of malaria and better than either Amodiaquine or Ciprofloxacin singly at their recommended dosage levels.

  17. Effects of low levels of ciprofloxacin on a chemostat model of the human colonic microflora.

    Science.gov (United States)

    Carman, R J; Woodburn, M A

    2001-06-01

    To study the utility of an in vitro model system for assessing the effect of low concentrations of a fluoroquinolone (FQ) drug on the ecology of the human intestinal microflora, chemostats containing human fecal flora were exposed to 0.43, 4.3, and 43microg of ciprofloxacin (CI) per milliliter. Prior to and during drug exposure, we assayed short-chain fatty acids (SCFA), bacterial populations, and the relative levels of susceptibility of these populations to CI and trovafloxacin (TV), a newer related FQ with increased activity against anaerobes. The degree to which CI affected the chemostat ecology was measured statistically by comparing observed data with the corresponding predicted "no effect" level. No changes in total SCFA were observed; only butyrate was significantly higher at the intermediate and high-dose levels. Enterococci counts and the levels of susceptibility to CI among enterococci were also unaffected. Escherichia coli counts decreased in a dose-dependent manner. Susceptibility levels in E. coli followed no interpretable pattern. Bacteroides fragilis group (BfG) counts decreased significantly following exposure to 43 and 4.3microg/mL CI. Ciprofloxacin susceptibility among the BfG in these chemostats was not determined because the BfG counts were too low (less than 30 colonies per plate) when undiluted chemostat samples were plated. However, within 2 days of exposure to 0.43microg/mL CI, the percentage of BfG resistant to 4microg/mL CI increased to over 95%. Before exposure, all BfG were susceptible to both CI (2microg/mL) and TV (0.25microg/mL). All BfG isolated during exposure were resistant to both CI (4microg/mL) and TV (2microg/mL). Resistance selection in the BfG was unexpected as the MIC(90) of CI for B. fragilis is 8microg/mL. Since the average colon flora is about 20% B. fragilis and other bacteroides, CI may impact the human gut flora even at subtherapeutic levels.

  18. Toxin production and antibiotic resistances in Escherichia coli isolated from bathing areas along the coastline of the Oslo fjord.

    Science.gov (United States)

    Charnock, Colin; Nordlie, Anne-Lise; Hjeltnes, Bjarne

    2014-09-01

    The presence of enterovirulent and/or antibiotic resistant strains of Escherichia coli in recreational bathing waters would represent a clear health issue. In total, 144 E. coli isolated from 26 beaches along the inner Oslo fjord were examined for virulence determinants and resistance to clinically important antibiotics. No isolates possessed the genetic determinants associated with enterotoxigenic strains and none showed the prototypic sorbitol negative, O157:H7 phenotype. A small number (∼1 %) produced alpha-hemolysin. Occurrences and patterns of antibiotic resistances were similar to those of E. coli isolated previously from environmental samples. In total, 6 % of the strains showed one or more clinically relevant resistances and 1.4 % were multi-drug resistant. Microarray analyses suggested that the resistance determinants were generally associated with mobile genetic elements. Resistant strains were not clonally related, and were, furthermore not concentrated at one or a few beach sites. This suggests that these strains are entering the waters at a low rate but in a widespread manner. The study demonstrates that resistant E. coli are present in coastal bathing waters where they can come into contact with bathers, and that the resistance determinants are potentially transferable. Some of the resistances registered in the study are to important antibiotics used in human medicine such as fluoroquinolones. The spread of antibiotic resistant genes, from the clinical setting to the environment, has clear implications with respect to the current management of bacterial infections and the long term value of antimicrobial therapy. The present study is the first of its kind in Norway.

  19. Longitudinal Comparison of Antibiotic Resistance in Diarrheagenic and Non-pathogenic Escherichia coli from Young Tanzanian Children.

    Science.gov (United States)

    Seidman, Jessica C; Johnson, Lashaunda B; Levens, Joshua; Mkocha, Harran; Muñoz, Beatriz; Silbergeld, Ellen K; West, Sheila K; Coles, Christian L

    2016-01-01

    Enteroaggregative, enteropathogenic, and enterotoxigenic Escherichia coli contribute significantly to the burden of diarrheal infections particularly in developing countries. Antibiotic resistance is increasingly common among bacterial pathogens including pathogenic E. coli. We assessed the relationship between pathogenic E. coli carriage and resistance to six antibiotics in E. coli isolated from young children in rural Tanzania. We surveyed temporal stability in antibiotic resistance in 2492 E. coli isolated from fecal samples obtained from young children in rural Tanzania collected over a 6 months period. Approximately half of the 377 children sampled were exposed to an azithromycin mass treatment program for trachoma control and half resided in control villages. Children were sampled at baseline, 1-, 3-, and 6 months following azithromycin treatment. We compared resistance to six antibiotics in pathogenic and non-pathogenic strains at the population level, within fecal specimens, and within individuals over time using chi-square tests, paired odds ratios, and logistic regression, respectively. Resistance to ampicillin and trimethoprim/sulfamethoxazole was highly prevalent (>65%). Resistance to 5 of 6 antibiotics tested and multi-drug resistance occurred more frequently in pathogenic isolates (p ≤ 0.001) within fecal specimens and overall. Azithromycin mass treatment exposure was significantly associated with increased odds of carriage of isolates resistant to erythromycin (OR 3.64, p < 0.001) and trimethoprim/sulfamethoxazole (OR 1.60, p < 0.05). Pathogenic isolates were approximately twice as likely to be resistant to erythromycin, ampicillin, or trimethoprim/sulfamethoxazole compared to non-pathogenic isolates from the same fecal specimen. The potential linkage between resistance and virulence in E. coli suggests hygiene and sanitation interventions aimed at reducing disease burden could play a role in controlling transmission of antibiotic resistance. PMID

  20. Longitudinal Comparison of Antibiotic Resistance in Diarrheagenic and Non-pathogenic Escherichia coli from Young Tanzanian Children

    Science.gov (United States)

    Seidman, Jessica C.; Johnson, Lashaunda B.; Levens, Joshua; Mkocha, Harran; Muñoz, Beatriz; Silbergeld, Ellen K.; West, Sheila K.; Coles, Christian L.

    2016-01-01

    Enteroaggregative, enteropathogenic, and enterotoxigenic Escherichia coli contribute significantly to the burden of diarrheal infections particularly in developing countries. Antibiotic resistance is increasingly common among bacterial pathogens including pathogenic E. coli. We assessed the relationship between pathogenic E. coli carriage and resistance to six antibiotics in E. coli isolated from young children in rural Tanzania. We surveyed temporal stability in antibiotic resistance in 2492 E. coli isolated from fecal samples obtained from young children in rural Tanzania collected over a 6 months period. Approximately half of the 377 children sampled were exposed to an azithromycin mass treatment program for trachoma control and half resided in control villages. Children were sampled at baseline, 1-, 3-, and 6 months following azithromycin treatment. We compared resistance to six antibiotics in pathogenic and non-pathogenic strains at the population level, within fecal specimens, and within individuals over time using chi-square tests, paired odds ratios, and logistic regression, respectively. Resistance to ampicillin and trimethoprim/sulfamethoxazole was highly prevalent (>65%). Resistance to 5 of 6 antibiotics tested and multi-drug resistance occurred more frequently in pathogenic isolates (p ≤ 0.001) within fecal specimens and overall. Azithromycin mass treatment exposure was significantly associated with increased odds of carriage of isolates resistant to erythromycin (OR 3.64, p < 0.001) and trimethoprim/sulfamethoxazole (OR 1.60, p < 0.05). Pathogenic isolates were approximately twice as likely to be resistant to erythromycin, ampicillin, or trimethoprim/sulfamethoxazole compared to non-pathogenic isolates from the same fecal specimen. The potential linkage between resistance and virulence in E. coli suggests hygiene and sanitation interventions aimed at reducing disease burden could play a role in controlling transmission of antibiotic resistance. PMID

  1. Patterns of antimicrobial resistance in pathogenic Escherichia coli isolates from cases of calf enteritis during the spring-calving season.

    Science.gov (United States)

    Gibbons, James F; Boland, Fiona; Buckley, James F; Butler, Francis; Egan, John; Fanning, Séamus; Markey, Bryan K; Leonard, Finola C

    2014-05-14

    Neonatal enteritis is a common condition of young calves and can be caused by pathogenic strains of Escherichia coli. We hypothesised that on-farm antimicrobial use would result in an increased frequency of resistance in these strains during the calving season. We also sought to determine if the frequency of resistance reflected on-farm antimicrobial use. Faecal samples were collected from cases of calf enteritis on 14 spring-calving dairy farms during two 3 week periods: Period 1 - February 11th through March 2nd 2008 and Period 2 - April 14th through May 5th 2008. E. coli were cultured from these samples, pathogenic strains were identified and antimicrobial susceptibility testing was carried out on these pathogenic isolates. Antimicrobial prescribing data were collected from each farm for the previous 12 months as an indicator of antimicrobial use. The correlation between antimicrobial use and resistance was assessed using Spearman's correlation coefficient. Logistic regression analysis was used to investigate the relationship between resistance, sampling period and pathotype. Penicillins and aminopenicillins, streptomycin, and tetracyclines were the most frequently prescribed antimicrobials and the greatest frequencies of resistance were detected to these 3 antimicrobial classes. A strong correlation (ρ=0.879) was observed between overall antimicrobial use and frequencies of antimicrobial resistance on farms. Sampling period was significant in the regression model for ampicillin resistance while pathotype was significant in the models for streptomycin, tetracycline and trimethoprim/sulphamethoxazole resistance. The frequencies of resistance observed have implications for veterinary therapeutics and prudent antimicrobial use. Resistance did not increase during the calving season and factors other than antimicrobial use, such as calf age and bacterial pathotype, may influence the occurrence of resistance in pathogenic E. coli.

  2. Prevalence of multi-antimicrobial-agent resistant, shiga toxin and enterotoxin producing Escherichia coli in surface waters of river Ganga.

    Science.gov (United States)

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p river Ganga water poses increased risk of infections in the human population.

  3. Nickel and cobalt resistance engineered in Escherichia coli by overexpression of serine acetyltransferase from the nickel hyperaccumulator plant Thlaspi goesingense.

    Science.gov (United States)

    Freeman, John L; Persans, Michael W; Nieman, Ken; Salt, David E

    2005-12-01

    The overexpression of serine acetyltransferase from the Ni-hyperaccumulating plant Thlaspi goesingense causes enhanced nickel and cobalt resistance in Escherichia coli. Furthermore, overexpression of T. goesingense serine acetyltransferase results in enhanced sensitivity to cadmium and has no significant effect on resistance to zinc. Enhanced nickel resistance is directly related to the constitutive overactivation of sulfur assimilation and glutathione biosynthesis, driven by the overproduction of O-acetyl-L-serine, the product of serine acetyltransferase and a positive regulator of the cysteine regulon. Nickel in the serine acetyltransferase-overexpressing strains is not detoxified by coordination or precipitation with sulfur, suggesting that glutathione is involved in reducing the oxidative damage imposed by nickel. PMID:16332856

  4. Prevalence of multi-antimicrobial-agent resistant, shiga toxin and enterotoxin producing Escherichia coli in surface waters of river Ganga.

    Science.gov (United States)

    Ram, Siya; Vajpayee, Poornima; Shanker, Rishi

    2007-11-01

    The consumption of polluted surface water for domestic and recreational purposes by large populations in developing nations is a major cause of diarrheal disease related mortality. The river Ganga and its tributaries meet 40% of the water requirement for drinking and irrigation in India. In this study, Escherichia coli isolates (n=75) of the river Ganga water were investigated for resistance to antimicrobial agents (n=15) and virulence genes specific to shiga toxin (STEC) and enterotoxin producing E. coli (ETEC). E. coli isolates from the river Ganga water exhibit resistance to multiple antimicrobial agents. The distribution of antimicrobial agent resistance in E. colivaries significantly (chi2: 81.28 at df = 24, p river Ganga water poses increased risk of infections in the human population. PMID:18044515

  5. Antibiotic resistance patterns of Escherichia coli strains isolated from surface water and groundwater samples in a pig production area

    Directory of Open Access Journals (Sweden)

    Roger Neto Schneider

    2009-09-01

    Full Text Available The use of antibiotics, so excessive and indiscriminate in intensive animal production, has triggered an increase in the number of resistant microorganisms which can be transported to aquatic environments. The aim of this study was to determine the profile of the antimicrobial resistance of samples of Escherichia coli isolated from groundwater and surface water in a region of pig breeding. Through the test of antimicrobial susceptibility, we analyzed 205 strains of E. coli. A high rate of resistance to cefaclor was observed, both in surface water (51.9% and groundwater (62.9%, while all samples were sensitive to amikacin. The percentages of multi-resistant samples were 25.96% and 26.73% in surface water and groundwater, respectively, while 19.23% and 13.86% were sensitive to all antibiotics tested. It was determined that the rate of multiple antibiotic resistance (MAR was 0.164 for surface water and 0.184 for groundwater. No significant differences were found in the profile of the antimicrobial resistance in strains of E. coli isolated in surface water and groundwater, but the index MAR calculated in certain points of groundwater may offer a potential risk of transmission of resistant genes.

  6. Antimicrobial drug resistance of Escherichia coli isolated from poultry abattoir workers at risk and broilers on antimicrobials

    Directory of Open Access Journals (Sweden)

    J.W. Oguttu

    2008-05-01

    Full Text Available Antimicrobial usage in food animals increases the prevalence of antimicrobial drug resistance among their enteric bacteria. It has been suggested that this resistance can in turn be transferred to people working with such animals, e.g. abattoir workers. Antimicrobial drug resistance was investigated for Escherichia coli from broilers raised on feed supplemented with antimicrobials, and the people who carry out evisceration, washing and packing of intestines in a high-throughput poultry abattoir in Gauteng, South Africa. Broiler carcasses were sampled from 6 farms, on each of which broilers are produced in a separate 'grow-out cycle'. Per farm, 100 caeca were randomly collected 5 minutes after slaughter and the contents of each were selectively cultured for E. coli. The minimum inhibitory concentration (MIC of each isolate was determined for the following antimicrobials : doxycycline, trimethoprim, sulphamethoxazole, ampicillin, enrofloxacin, fosfomycin, ceftriaxone and nalidixic acid. The same was determined for the faeces of 29 abattoir workers and 28 persons used as controls. The majority of isolates from broilers were resistant, especially to antimicrobials that were used on the farms in the study. Overall median MICs and the number of resistant isolates from abattoir workers (packers plus eviscerators tended to be higher than for the control group. However, no statistically significant differences were observed when the median MICs of antimicrobials used regularly in poultry and percentage resistance were compared, nor could an association between resistance among the enteric E. coli from packers and those from broilers be demonstrated.

  7. Substrate specificity of the OqxAB multidrug resistance pump in Escherichia coli and selected enteric bacteria

    DEFF Research Database (Denmark)

    Hansen, Lars Hestbjerg; Jensen, Lars Bogø; Sørensen, Heidi Iskou;

    2007-01-01

    a variety of substrates in E. coli. These included animal growth promoters, antimicrobials, disinfectants and detergents. pOLA52 could readily be transferred to enterobacterial pathogens. Transconjugants showed reduced susceptibility towards chloramphenicol, ciprofloxacin and olaquindox. Conclusions...

  8. 喹诺酮耐药大肠埃希菌尿道感染现状及危险因素分析%Quinolone resistant Escherichia coli isolated from urinary tract infection:clinical status and risk factors

    Institute of Scientific and Technical Information of China (English)

    张安兵

    2012-01-01

    Objective To investigate the quinolone resistant Escherkhia coli infection status and risk factors, and provide a basis for selecting appropriate antibiotics in the clinical practice. Methods This study is a retrospective review from 2010 to 2011. 348 strains Escherichia coli isolated from urine specimens were analysis, using the quinolone susceptible isolates as the control group. The risk factors for the quinolone resistance strains were analyzed. Results Of the 348 E.coli strains isolated from urinary tract infection patient, 58.3% (203)were quinolone resistant. Logistic regression analysis showed three generation cephalosporins and quinolones drug use, urinary drainage and bacterium producing extra-broad spectrum beta-lactamase were the independent risk factors for ciprofloxacin resistance of E.coli strains isolated from urinary tract infection patients. Conclusion The epidemic of quinolone resistant Escherichia coli isolated from urine specimens were extremely serious. The drug resistance of the quinolone resistant isolates was strong. The patients infected with quinolone resistant strains had high medical cost and longer average length of stay in hospital. The quinolone resistant E.coli infection with multiple independent risk factors, the strengthening of these independent risk factor controls can effectively prevent the spread of quinolone resistant strains infection.%目的 分析喹诺酮耐药大肠埃希菌尿道感染现状及危险因素,为临床合理选用抗生素提供依据.方法 回顾性分析348例大肠埃希菌尿道感染临床现状,以喹诺酮敏感大肠埃希菌为对照菌株,对喹诺酮耐药大肠埃希菌感染危险因素进行分析.结果 348株大肠埃希菌尿道感染中检出喹诺酮耐药菌203株,占58.3%.Logistic回归分析显示三代头孢菌素及喹诺酮类药物使用、尿路引流和细菌产超广谱β-内酰胺酶是喹诺酮耐药大肠埃希菌感染的独立危险因素.结论 尿道感染大肠埃

  9. The changing pattern of antimicrobial resistance within 42,033 Escherichia coli isolates from nosocomial, community and urology patient-specific urinary tract infections, Dublin, 1999-2009.

    LENUS (Irish Health Repository)

    Cullen, Ivor M

    2012-04-01

    To investigate the changing pattern of antimicrobial resistance in Escherichia coli urinary tract infection over an eleven year period, and to determine whether E. coli antibiotic resistance rates vary depending on whether the UTI represents a nosocomial, community acquired or urology patient specific infection.

  10. Use of the D-R model to define trends in the emergence of Ceftazidime-resistant Escherichia coli in China

    Science.gov (United States)

    Objective: To assess the efficacy of the D-R model for defining trends in the appearance of Ceftazidime-resistant Escherichia coli. Methods: Actual data related to the manifestation of Ceftazidime-resistant E.coli spanning years 1996-2009 were collected from the China National Knowledge Internet (CN...

  11. Strukturelle Charakterisierung eines unbekannten Metaboliten von Ciprofloxacin [Structural characterization of an unknown metabolite of ciprofloxacin

    OpenAIRE

    Kees, Frieder K.; Raasch, W.; Grobecker, H. F.

    1992-01-01

    The chemical structure of an unknown metabolite of ciprofloxacin (CAS 85721-33-1) is characterized by means of reversed phase ion pair liquid chromatography, absorption and fluorescence spectroscopy, partition coefficients as well as chemical and enzymatic hydrolytic degradation. A chemical structure of the unknown metabolite is proposed: N-formyl-desethylen-ciprofloxacin. It can be formed as an intermediate in the oxidative degradation of ciprofloxacin via oxociprofloxacin to desethylen-cipr...

  12. A spatial approach for the epidemiology of antibiotic use and resistance in community-based studies: the emergence of urban clusters of Escherichia coli quinolone resistance in Sao Paulo, Brasil

    Science.gov (United States)

    2011-01-01

    Background Population antimicrobial use may influence resistance emergence. Resistance is an ecological phenomenon due to potential transmissibility. We investigated spatial and temporal patterns of ciprofloxacin (CIP) population consumption related to E. coli resistance emergence and dissemination in a major Brazilian city. A total of 4,372 urinary tract infection E. coli cases, with 723 CIP resistant, were identified in 2002 from two outpatient centres. Cases were address geocoded in a digital map. Raw CIP consumption data was transformed into usage density in DDDs by CIP selling points influence zones determination. A stochastic model coupled with a Geographical Information System was applied for relating resistance and usage density and for detecting city areas of high/low resistance risk. Results E. coli CIP resistant cluster emergence was detected and significantly related to usage density at a level of 5 to 9 CIP DDDs. There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. Conclusions There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. The usage density of 5-9 CIP DDDs per 1,000 inhabitants within the same influence zone was the resistance triggering level. This level led to E. coli resistance clustering, proving that individual resistance emergence and dissemination was affected by antimicrobial population consumption. PMID:21356088

  13. A spatial approach for the epidemiology of antibiotic use and resistance in community-based studies: the emergence of urban clusters of Escherichia coli quinolone resistance in Sao Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Bailey Trevor C

    2011-02-01

    Full Text Available Abstract Background Population antimicrobial use may influence resistance emergence. Resistance is an ecological phenomenon due to potential transmissibility. We investigated spatial and temporal patterns of ciprofloxacin (CIP population consumption related to E. coli resistance emergence and dissemination in a major Brazilian city. A total of 4,372 urinary tract infection E. coli cases, with 723 CIP resistant, were identified in 2002 from two outpatient centres. Cases were address geocoded in a digital map. Raw CIP consumption data was transformed into usage density in DDDs by CIP selling points influence zones determination. A stochastic model coupled with a Geographical Information System was applied for relating resistance and usage density and for detecting city areas of high/low resistance risk. Results E. coli CIP resistant cluster emergence was detected and significantly related to usage density at a level of 5 to 9 CIP DDDs. There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. Conclusions There were clustered hot-spots and a significant global spatial variation in the residual resistance risk after allowing for usage density. The usage density of 5-9 CIP DDDs per 1,000 inhabitants within the same influence zone was the resistance triggering level. This level led to E. coli resistance clustering, proving that individual resistance emergence and dissemination was affected by antimicrobial population consumption.

  14. Analysis on drug resistance of Escherichia coli resistant to Levofloxacin%耐左氧氟沙星大肠埃希菌的耐药性分析

    Institute of Scientific and Technical Information of China (English)

    游春芳; 周利民; 张肃川; 殷明刚; 伍欢

    2011-01-01

    Objective To investigate the isolated rate of Escherichia coli a-mong Zigong First Peoples' Hospital and analyze the drug resistance of strains resistant to Levofloxacin. Methods Kirby-Bauer' s detection technique was applied to detect the resistance feature in 154 strains of Escherichia coli collected from August 2009 to August 2010. Results Total of 76 strains resisted to Levofloxacin were detected in 154 strains of Escherichia coli, with the detection rate as 49.35%. Among the specimens, the isolated rate of strains resistant to Levofloxacin in urina was the highest (51. 32% ) and the second was in sputum ( 23. 68% ). Except for imipenem, mlopen-em, cefoxitin, piperacillin/tazobatan and amikacin, the resistance rate of Levofloxa-cin-resistant strains were significantly higher than that of non-Levofloxacin-resistant strains to ampicillin, cefazolin, cefepime, cefotaxime, ceftazidime, gentamycin, cef-operazone/sulbactam ( P < 0. 05 ). Conclusions Levofloxacin-resistant Escherichia coli is resistant to many antibacterial agents. Monitoring of Levofloxacin-resistantstrains should be strengthened and the indication of antibiotics must be mastered strictly to prevent the dissemination of drug resistant strains.%目的 了解本院临床分离的大肠埃希菌的耐药情况,分析耐左氧氟沙星细菌的耐药性.方法 对2009年8月至2010年8月本院临床分离的154株大肠埃希菌用Kirby-Bauer琼脂扩散法进行药物敏感试验.结果 154株大肠埃希菌中共检出耐左氧氟沙星菌76株,检出率49.35%.在各类标本中,尿液中耐左氧氟沙星菌株分离率最高(51.32%),其次为痰(23.68%).除亚胺培南、美罗培南、头孢西丁、哌拉西林/他唑巴坦和阿米卡星外,耐左氧氟沙星菌株对氨苄西林、头孢唑啉、头孢吡肟、头孢噻肟、头孢他啶、庆大霉素、头孢哌酮/舒巴坦的耐药率明显高于非耐左氧氟沙星菌株(P< 0.05).结论 本院耐左氧氟沙星大肠埃希菌株对多种

  15. Characterisation, dissemination and persistence of gentamicin resistant Escherichia coli from a Danish university hospital to the waste water environment

    DEFF Research Database (Denmark)

    Jakobsen, Lotte; Sandvang, Dorthe; Hansen, Lars H;

    2008-01-01

    The aim of the study was to investigate the potential spread of gentamicin resistant (GEN(R)) Escherichia coli isolates or GEN(R) determinants from a Danish university hospital to the waste water environment. Waste water samples were collected monthly from the outlets of the hospital bed wards...... in waste water from the residential area. PFGE profiling revealed no spread of specific patient isolates to the waste water. The aac(3)-II gene was detected both in patient and waste water isolates. Furthermore horizontal transfer of the aac(3)-II gene of patient origin to a recipient was shown in vitro...

  16. Comparison of the Transport of Tetracycline-Resistant and Tetracycline-Susceptible Escherichia coli Isolated from Lake Michigan

    OpenAIRE

    Walczak, Jacob J.; Bardy, Sonia L.; Feriancikova, Lucia; Xu, Shangping

    2011-01-01

    It was recently reported that tetracycline could enhance the mobility of manure-derived Escherichia coli within saturated porous media (Walczak et al. (Water Research 45:1681–1690, 2011)). It was also shown, however, that E. coli from various sources could display marked variation in their mobility (Bolster et al. (Journal of Environmental Quality 35:1018–1025, 2009)). The focus of this research was to examine if the observed difference in the mobility of manure-derived tetracycline-resistant...

  17. Profiling of antimicrobial resistance and plasmid replicon types in β-lactamase producing Escherichia coli isolated from Korean beef cattle

    OpenAIRE

    Shin, Seung Won; Jung, Myunghwan; Shin, Min-Kyung; Yoo, Han Sang

    2015-01-01

    In this study, 78 isolates of Escherichia coli isolated from Korean beef cattle farms were investigated for the production of extended-spectrum β-lactamase (ESBL) and/or AmpC β-lactamase. In the disc diffusion test with ampicillin, amoxicillin, cephalothin, ceftiofur, cefotaxime, ceftazidime, and cefoxitin, 38.5% of the isolates showed resistance to all of ampicillin, amoxicillin, and cephalothin. The double disc synergy method revealed that none of the isolates produced ESBL or AmpC β-lactam...

  18. Investigation of Biofield Treatment on Antimicrobial Susceptibility, Biochemical Reaction Pattern and Biotyping of Enteropathogenic Multidrug-Resistant Escherichia coli Isolates

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Study background: Multidrug resistant Escherichia coli (MDR E. coli) has become a major health concern, and failure of treatment leads to huge health burden. Aim of the present study was to determine the impact of Mr. Trivedi’s biofield treatment on E. coli. Methods: Four MDR clinical lab isolates (LSs) of E. coli (LS 8, LS 9, LS 10, and LS 11) were taken and divided into two groups i.e. control and biofield treated. Control and treated samples were identified with respect...

  19. Genetic relationship between soxRS and mar loci in promoting multiple antibiotic resistance in Escherichia coli.

    OpenAIRE

    Miller, P F; Gambino, L F; Sulavik, M. C.; Gracheck, S. J.

    1994-01-01

    Multiple antibiotic resistance in Escherichia coli has typically been associated with mutations at the mar locus, located at 34 min on the E. coli chromosome. A new mutant, marC, isolated on the basis of a Mar phenotype but which maps to the soxRS (encoding the regulators of the superoxide stress response) locus located at 92 min, is described here. This mutant shares several features with a known constitutive allele of the soxRS gene, prompting the conclusion that it is a highly active allel...

  20. Pharmacodynamic profiling of commonly prescribed antimicrobial drugs against Escherichia coli isolates from urinary tract

    Directory of Open Access Journals (Sweden)

    Gabriel Trova Cuba

    2014-09-01

    Full Text Available Since antimicrobial resistance among uropathogens against current first line agents has affected the management of severe urinary tract infection, we determined the likelihood that antibiotic regimens achieve bactericidal pharmacodynamic exposures using Monte Carlo simulation for five antimicrobials (ciprofloxacin, ceftriaxone, piperacillin/tazobactam, ertapenem, and meropenem commonly prescribed as initial empirical treatment of inpatients with severe community acquired urinary tract infections. Minimum inhibitory concentration determination by Etest was performed for 205 Brazilian community urinary tract infection Escherichia coli strains from 2008 to 2012 and 74 E. coli bloodstream strains recovered from a surveillance study. Pharmacodynamic exposure was modeled via a 5000 subject Monte Carlo simulation. All isolates were susceptible to ertapenem and meropenem. Piperacillin/tazobactam, ceftriaxone and ciprofloxacin showed 100%, 97.5% and 83.3% susceptibility among outpatient isolates and 98.6%, 75.7% and 64.3% among inpatient isolates, respectively. Against outpatient isolates, all drugs except ciprofloxacin (82.7% in aggressive and 77.6% in conservative scenarios achieved high cumulative fraction of response: car-bapenems and piperacillin/tazobactam cumulative fraction of responses were close to 100%, and ceftriaxone cumulative fraction of response was 97.5%. Similar results were observed against inpatients isolates for carbapenems (100% and piperacillin/tazobactam (98.4%, whereas ceftriaxone achieved only 76.9% bactericidal cumulative fraction of response and ciprofloxacin 61.9% (aggressive scenario and 56.7% (conservative scenario respectively. Based on this model, standard doses of beta-lactams were predicted to deliver sufficient pharmacodynamic exposure for outpatients. However, ceftriaxone should be avoided for inpatients and ciprofloxacin empirical prescription should be avoided in both inpatients and outpatients with complicated

  1. Comparative mutant prevention concentration and antibacterial activity of fluoroquinolones against Escherichia coli in diarrheic buffalo calves.

    Science.gov (United States)

    Beri, Supriya; Sidhu, Pritam K; Kaur, Gurpreet; Chandra, Mudit; Rampal, Satyavan

    2015-10-01

    Owing to emerging threat of antimicrobial resistance, mutant prevention concentration (MPC) is considered as an important parameter to evaluate the antimicrobials for their capacity to restrict/allow the emergence of resistant mutants. Therefore, MPCs of ciprofloxacin, enrofloxacin, levofloxacin, moxifloxacin, and norfloxacin were determined against Escherichia coli isolates of diarrheic buffalo calves. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were also established. The MICs of ciprofloxacin, enrofloxacin, levofloxacin, moxifloxacin and norfloxacin were 0·009, 0·022, 0·024, 0·028, and 0·036 μg/ml, respectively. The MBCs obtained were very close to the MICs of respective drugs that suggested a bactericidal mode of action of antimicrobials. The MPCs (μg/ml) of ciprofloxacin (4·2×MIC), moxifloxacin (4·8×MIC), and norfloxacin (5·1×MIC) were approximately equal but slightly lower than enrofloxacin (7·6×MIC) and levofloxacin (8·5×MIC) against clinical isolates of E. coli. The MPC data suggested that enrofloxacin has the potential for restricting the selection of E. coli mutants during treatment at appropriate dosing.

  2. Characterization of the variable region in the class 1 integron of antimicrobial-resistant Escherichia coli isolated from surface water

    Directory of Open Access Journals (Sweden)

    Natália Canal

    2016-06-01

    Full Text Available Abstract Fecal bacteria are considered to be a potential reservoir of antimicrobial resistance genes in the aquatic environment and could horizontally transfer these genes to autochthonous bacteria when carried on transferable and/or mobile genetic elements. Such circulation of resistance genes constitutes a latent public health hazard. The aim of this study was to characterize the variable region of the class 1 integron and relate its genetic content to resistance patterns observed in antimicrobial-resistant Escherichia coli isolated from the surface waters of Patos Lagoon, Southern Brazil. Genetic diversity of the isolates and presence of the qacEΔ1 gene, which confers resistance to quaternary ammonium compounds, were also investigated. A total of 27 isolates were analyzed. The variable region harbored dfrA17, dfrA1 and dfrA12 genes, which confer resistance to trimethoprim, and aadA1, aadA5 and aadA22 genes that encode resistance to streptomycin/spectinomycin. Most of the isolates were considered resistant to quaternary ammonium compounds and all of them carried the qacE Δ1 gene at the 3′ conserved segment of the integron. ERIC-PCR analyses of E. coli isolates that presented the integrons showed great genetic diversity, indicating diverse sources of contamination in this environment. These results suggest that fecal bacteria with class 1 integrons in aquatic environments are potentially important reservoirs of antibiotic-resistance genes and may transfer these elements to other bacteria that are capable of infecting humans.

  3. The Mechanism of Resistance Inhibition of Plantago asiatica L. Extracts to Escherichia coli%车前子提取物对大肠杆菌耐药抑制作用初步研究

    Institute of Scientific and Technical Information of China (English)

    向华; 赵晴; 马红霞

    2014-01-01

    To evaluate the antibiotic effects of ciprofloxacin combined with extracts of Plantago asiatica L. against Escherichia coli using the checkerboard method. The FIC index was calculated according to MIC ( Minimum inhibitory concentrations) results. Results suggested the additivity of ciprofloxacin combined with Plantago asiatica L. The influence on efflux pump was assessed by kinetics evaluation of ciprofloxacin in the dynamics of accumulation. The alcohol extracts of Plantago asiatica L. increased the cellular accumulation of ciprofloxacin. Chloroform extracts effectively inhibited efflux pump in J strain of Escherichia coli.%为了对车前子提取物耐药抑制作用进行研究,采用棋盘法测定车前子乙醇提取物与环丙沙星的联合作用,二者联合应用对大肠杆菌耐药菌株具有较好的抗菌作用。通过环丙沙星蓄积动力学试验检测车前子乙醇提取物对鸡源大肠杆菌外排泵的影响,结果表明,车前子乙醇提取物能增加环丙沙星在细胞内的蓄积量,抑制耐药大肠杆菌对抗生素的主动外排作用。三氯甲烷萃取物对大肠杆菌的药物外排具有一定的抑制作用,但其抑制作用不如乙醇提取物。

  4. Ciprofloxacin in imaging of infective versus sterile inflammation

    International Nuclear Information System (INIS)

    Ciprofloxacin (CIP) was labelled with 99Tcm. The radiolabelled efficiency monitored by ITLC and HPLC was higher than 95%. The 99Tcm-CIP complex analyzed by those systems have shown that inactive and labelled CIP exhibit different chromatographic behavior. This finding together with octanol/saline partition coefficients determination indicated that CIP and 99Tcm-CIP correspond to different chemical structure. Biodistribution studies in inflamed mice shown that 99Tcm-CIP is rapidly distributed after i. v. administration with a predominant renal clearance. The radioactive preparation is able to localize bacterial and sterile inflammations induced by Staphylococcus aureus, Escherichia coli and turpentine, which suggest that its accumulation is due to increased blood flow together with enhanced vascular permeability as also postulated to other non-specific radiopharmaceuticals. (author)

  5. Antibiotic Resistance among Urinary Isolates from Female Outpatients in the United States in 2003 and 2012.

    Science.gov (United States)

    Sanchez, Guillermo V; Babiker, Ahmed; Master, Ronald N; Luu, Tony; Mathur, Anisha; Bordon, Jose

    2016-05-01

    A retrospective analysis was performed using The Surveillance Network, USA, to examine the prevalence of antibiotic resistance among urine isolates from U.S. female outpatients in 2012 and assessed trends in antibiotic resistance comparing data from 2003 and 2012. The most common pathogen identified in 2012 (n = 285,325) was Escherichia coli (64.9% of isolates). In 2012, E. coli resistance to nitrofurantoin was low (<3%) across all age groups. E. coli resistance to ciprofloxacin was high among adults (11.8%) and elderly outpatients (29.1%). When comparing the 2003 and 2012 data from isolates from adults, E. coli resistance to nitrofurantoin changed only slightly (from 0.7% to 0.9%), whereas increases in resistance to ciprofloxacin (3.6% to 11.8%) and trimethoprim-sulfamethoxazole (17.2% to 22.2%) changed substantially. In the United States, E. coli has become increasingly resistant to ciprofloxacin and trimethoprim-sulfamethoxazole (TMP-SMX) in adult female outpatients. Nitrofurantoin retains high levels of antibiotic activity against urinary E. coli. PMID:26883714

  6. Variation in Resistance Traits, Phylogenetic Backgrounds, and Virulence Genotypes among Escherichia coli Clinical Isolates from Adjacent Hospital Campuses Serving Distinct Patient Populations

    OpenAIRE

    Drawz, Sarah M.; Porter, Stephen; Kuskowski, Michael A.; Johnston, Brian; Clabots, Connie; Kline, Susan; FERRIERI, PATRICIA; Johnson, James R.

    2015-01-01

    Escherichia coli sequence type 13 (ST131), an emergent cause of multidrug-resistant extraintestinal infections, has important phylogenetic subsets, notably the H30 and H30Rx subclones, with distinctive resistance profiles and, possibly, clinical associations. To clarify the local prevalence of these ST131 subclones and their associations with antimicrobial resistance, ecological source, and virulence traits, we extensively characterized 233 consecutive E. coli clinical isolates (July and Augu...

  7. Determinants of carriage of resistant Escherichia coli in the Indonesian population inside and outside hospitals

    NARCIS (Netherlands)

    O.D. Duerink (Offra); E.S. Lestari (Endang Sri); U. Hadi (Usman); N.J.D. Nagelkerke (Nico); J.A. Severin (Juliëtte); H.A. Verbrugh (Henri); M. Keuter (Monique); I.C. Gyssens (Inge); P. van den Broek (Peterhans)

    2007-01-01

    textabstractObjectives: Antibiotic resistance is a worldwide healthcare problem exacerbated by antibiotic use and transmission of resistant bacteria. Not much is known about resistance in commensal flora and about determinants for resistance in Indonesia. This study analysed recent antibiotic use as

  8. Resistência a antimicrobianos dependente do sistema de efluxo multidrogas em Escherichia coli isoladas de leite mastítico Antimicrobial resistance dependent on multidrugs efflux in Escherichia coli isolated from the mastitic milk

    Directory of Open Access Journals (Sweden)

    M.A.S. Moreira

    2008-12-01

    Full Text Available Identificaram-se e caracterizaram-se a resistência e a multirresistência aos principais antimicrobianos usados no tratamento de mastite bovina causada por Escherichia coli. A concentração inibitória mínima (MIC e o sistema de efluxo foram detectados pelas curvas de crescimento, com base na densidade óptica, em diferentes concentrações da droga e na presença e na ausência do desacoplador da força próton-motora (PMF. E. coli 1 foi resistente à neomicina e à gentamicina; E. coli 3 e 4, à tetraciclina e à estreptomicina; e E. coli 2 e 6 à gentamicina. E. coli 5 apresentou modelo de sensibilidade. Observou-se que MICs de todos os antimicrobianos dos multirresistentes (E. coli 1, 3 e 4 diminuíram na presença do desacoplador, o que sugere sistema de efluxo multidrogas. Após cura, apenas E. coli 1 apresentou modelo de sensibilidade, porém não houve alterações das MICs, antes e após adição do desacoplador. Os resultados indicam possível presença de mecanismo de resistência dependente da PMF codificado, ou parte dele, em plasmídeo.Resistance and multiresistance to main antimicrobials used for treating bovine mastitis caused by Escherichia coli were identified and characterized. The minimal inhibitory concentration (MIC and efflux systems were detected by the use of growth curves based on optical density at different drug concentrations and both presence and absence of uncoupler of the proton-motive force (PMF. E. coli 1 was resistant to neomycin and gentamycin, E. coli 3 and 4 were resistant to tetracycline and streptomycin, whereas E. coli 2 and 6 were resistant to gentamycin. E. coli 5 showed sensibility model. MICs of all antimicrobials of the multiresistant samples (E. coli 1, 3, and 4 were decreased in presence of the uncoupler, therefore suggesting the presence of the multidrug efflux system. After healing, only E. coli 1 showed sensibility model, however no alteration occurred in MIC(s before and after adding the

  9. Analyzing indicator microorganisms, antibiotic resistant Escherichia coli, and regrowth potential of foodborne pathogens in various organic fertilizers.

    Science.gov (United States)

    Miller, Cortney; Heringa, Spencer; Kim, Jinkyung; Jiang, Xiuping

    2013-06-01

    This study analyzed various organic fertilizers for indicator microorganisms, pathogens, and antibiotic-resistant Escherichia coli, and evaluated the growth potential of E. coli O157:H7 and Salmonella in fertilizers. A microbiological survey was conducted on 103 organic fertilizers from across the United States. Moisture content ranged from approximately 1% to 86.4%, and the average pH was 7.77. The total aerobic mesophiles ranged from approximately 3 to 9 log colony-forming units (CFU)/g. Enterobacteriaceae populations were in the range of fertilizer, respectively, whereas E. coli O157:H7 grew approximately 4.6, 4.0, 4.0, and 4.8 log CFU/g, respectively. Our results revealed that the microbiological quality of organic fertilizers varies greatly, with some fertilizers containing antibiotic resistant E. coli and a few supporting the growth of foodborne pathogens after reintroduction into the fertilizer.

  10. Comparative analysis of antibiotic resistance and phylogenetic group patterns in human and porcine urinary tract infectious Escherichia coli

    DEFF Research Database (Denmark)

    Hancock, Viktoria; Nielsen, E.M.; Krag, L.;

    2009-01-01

    Urinary tract infections (UTIs) are one of the most common infectious diseases in humans and domestic animals such as pigs. The most frequent infectious agent in such infections is Escherichia coli. Virulence characteristics of E. coli UTI strains range from highly virulent pyelonephritis strains...... to relatively benign asymptomatic bacteriuria strains. Here we analyse a spectrum of porcine and human UTI E. coli strains with respect to their antibiotic resistance patterns and their phylogenetic groups, determined by multiplex PCR. The clonal profiles of the strains differed profoundly; whereas human...... strains predominantly belonged to clonal types B2 and D, these were not seen among the porcine strains, which all belonged to the E. coli clonal groups A and B1. Contrary to the human strains, the majority of the porcine strains were multidrug resistant. The distinct profiles of the porcine strains...

  11. Genotyping DNA chip for the simultaneous assessment of antibiotic resistance and pathogenic potential of extraintestinal pathogenic Escherichia coli.

    Science.gov (United States)

    Barl, Timo; Dobrindt, Ulrich; Yu, Xiaolei; Katcoff, Don J; Sompolinsky, David; Bonacorsi, Stéphane; Hacker, Jörg; Bachmann, Till T

    2008-09-01

    Urinary tract infections (UTIs) are among the most frequently occurring infections and are mostly caused by extraintestinal pathogenic Escherichia coli. DNA microarrays are potent molecular diagnostic tools for rapid diagnosis of bacterial infections with high relevance for UTIs. In this study, we present the integration and application of two DNA chip modules for the simultaneous detection of single nucleotide polymorphisms in gyrA (quinolone resistance) and fimH (increased adhesion to urinary tract epithelium). The performance of the combined diagnostic chip was assessed by genotyping 140 E. coli strains. Resistance-causing mutations could only be identified in UTI isolates. A complete genotyping assay could be performed in tool for routine clinical diagnostics. PMID:18640014

  12. Synthesis and characterisation of technetium-99m labelled ciprofloxacin (Infecton)

    International Nuclear Information System (INIS)

    Full text: Infecton is Tc-99m labelled Ciprofloxacin, which is a synthetic carboxyquinolone derivative with broad-spectrum antimicrobial activity. It is a new class of radiopharmaceutical designed for imaging live bacterial infection. Conventional imaging agents such as Tc-99m or In-111 labelled leucocytes are either time-consuming or hazardous due to blood handling. These can be obviated by the use of Infecton which we synthesised by modifying the procedure described by Britton and co-workers (Lancet 1996;..347: 233-235). Bioassay and animal studies have been performed with a view to its use in infection imaging in patients. The first task was to prepare pure ciprofloxacin from its commercially available lactate salt. This was achieved by isoelectric precipitation at pH 8.6 by adding sodium hydroxide to the formulation. The resultant precipitate was washed with 200 mL of water for injection and filtered through a cintered-glass filtering unit. The precipitate was free of lactate and sodium as analysed by Biochem analyser. The UV spectrophotometric analysis showed an absorption peak at 276.3 nm which is close to the theoretical value of 277 nm, thus confirming the purity of the compound. Infecton was synthesised by adding 2 mg of pure ciprofloxacin, 0.4 mg of formimidine sulfinic acid ( non-stannous reducing agent) and 1.0 GBq Tc-99m pertechnetate in a final volume of 1.0 mL saline into a sterile N2-filled Amersham vial and boiling the mixture at 100 deg C for 10 min. The purity of the product was 40-45%. It was passed through a DEAE Sephadex A-25 column and eluted with phosphate buffered saline (0.01M, pH 6.9) with a purity of >96%. The preparation was characterised by bioassay (n=3) by adding Infecton to four different broths of bacterial strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and MRSA with resultant binding of 50.4, 45.6, 48.5 and 50.3% respectively. The binding was less than 1.0% when either ciprofloxacin or

  13. Synthesis and characterisation of technetium-99m labelled ciprofloxacin (Infecton)

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, V.; Choong, K.K.L.; Olma, T.R.; Mieczkowski, S. [Westmead and the New Childrens Hospital, Westmead, NSW (Australia). Department of Nuclear Medicineand Ultrasound and Centre for infectious Diseases and Microbiology laboratory Services

    1998-06-01

    Full text: Infecton is Tc-99m labelled Ciprofloxacin, which is a synthetic carboxyquinolone derivative with broad-spectrum antimicrobial activity. It is a new class of radiopharmaceutical designed for imaging live bacterial infection. Conventional imaging agents such as Tc-99m or In-111 labelled leucocytes are either time-consuming or hazardous due to blood handling. These can be obviated by the use of Infecton which we synthesised by modifying the procedure described by Britton and co-workers (Lancet 1996;..347: 233-235). Bioassay and animal studies have been performed with a view to its use in infection imaging in patients. The first task was to prepare pure ciprofloxacin from its commercially available lactate salt. This was achieved by isoelectric precipitation at pH 8.6 by adding sodium hydroxide to the formulation. The resultant precipitate was washed with 200 mL of water for injection and filtered through a cintered-glass filtering unit. The precipitate was free of lactate and sodium as analysed by Biochem analyser. The UV spectrophotometric analysis showed an absorption peak at 276.3 nm which is close to the theoretical value of 277 nm, thus confirming the purity of the compound. Infecton was synthesised by adding 2 mg of pure ciprofloxacin, 0.4 mg of formimidine sulfinic acid ( non-stannous reducing agent) and 1.0 GBq Tc-99m pertechnetate in a final volume of 1.0 mL saline into a sterile N{sub 2}-filled Amersham vial and boiling the mixture at 100 deg C for 10 min. The purity of the product was 40-45%. It was passed through a DEAE Sephadex A-25 column and eluted with phosphate buffered saline (0.01M, pH 6.9) with a purity of >96%. The preparation was characterised by bioassay (n=3) by adding Infecton to four different broths of bacterial strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and MRSA with resultant binding of 50.4, 45.6, 48.5 and 50.3% respectively. The binding was less than 1.0% when either ciprofloxacin or

  14. Rapid and sensitive detection of fluoroquinolone-resistant Escherichia coli from urine samples using a genotyping DNA microarray.

    Science.gov (United States)

    Yu, Xiaolei; Susa, Milorad; Weile, Jan; Knabbe, Cornelius; Schmid, Rolf D; Bachmann, Till T

    2007-10-01

    Urinary tract infections (UTI) are among the most common bacterial infections in humans, with Escherichia coli being the major cause of infection. Fluoroquinolone resistance of uropathogenic E. coli has increased significantly over the last decade. In this study a microarray-based assay was developed and applied, which provides a rapid, sensitive and specific detection of fluoroquinolone-resistant E. coli in urine. The capture probes were designed against previously identified and described hotspots for quinolone resistance (codons 83 and 87 of gyrA). The key goals of this development were to reduce assay time while increasing the sensitivity and specificity as compared with a pilot version of a gyrA genotyping DNA microarray. The performance of the assay was demonstrated with pure cultures of 30 E. coli isolates as well as with urine samples spiked with 6 E. coli isolates. The microarray results were confirmed by standard DNA sequencing and were in full agreement with the phenotypic antimicrobial susceptibility testing using standard methods. The DNA microarray test displayed an assay time of 3.5h, a sensitivity of 100CFU/ml, and the ability to detect fluoroquinolone-resistant E. coli in the presence of a 10-fold excess of fluoroquinolone-susceptible E. coli cells. As a consequence, we believe that this microarray-based determination of antibiotics resistance has a true potential for the application in clinical routine laboratories in the future.

  15. Molecular characterization and antimicrobial resistance of faecal and urinary Escherichia coli isolated from dogs and humans in Italy

    Directory of Open Access Journals (Sweden)

    Clara Tramuta

    2014-03-01

    Full Text Available During this study, 109 faecal Escherichia coli samples isolated from 61 dogs and 48 humans were characterised according to phylogenetic group, extraintestinal virulence factors and antibiotic resistance. The isolates from dogs were predominantly distributed within phylogroup B1 (36%, while the majority of human strains belonged to phylogroup B2 (54%. The prevalence of cnf1, hlyA, papC and sfa virulence genes was significantly associated with the group B2. Canine isolates showed multidrug resistance (MDR more frequently than human strains. Since group B2 contains most of the strains that cause extraintestinal infections, all 46 B2 faecal strains were confronted against an addition population of 57 urinary E. coli strains belonging to the same phylogroup. The comparison shows that there was no significant difference in the occurrence of virulence factors or in the distribution of antibiotic resistance between faecal and urinary E. coli isolates fromd dogs. At the same time, a highly significant association was detected between multiple resistence and the source of the strains and between MDR and E. coli isolated from urine in human. This study highlighted similar features of E. coli isolated across sources and hosts. The data suggest a high prevalence of antibiotic resistance in faecal strains, which may represent a serious health risk since these strains can function as a reservoir for uropathogenic E. coli.

  16. Escherichia coli ASKA Clone Library Harboring tRNA-Specific Adenosine Deaminase (tadA Reveals Resistance towards Xanthorrhizol

    Directory of Open Access Journals (Sweden)

    Yogiara

    2015-09-01

    Full Text Available Xanthorrhizol is a potent antimicrobial compound isolated from the rhizome of Curcuma xanthorrhiza. However, the mechanism of xanthorrhizol action is unknown. To screen for probable target(s, we introduced the ASKA pooled-plasmid library into Escherichia coli W3110 imp4213 and enriched the library for resistant clones with increasing concentrations of xanthorrhizol. After three rounds of enrichment, we found nine genes that increased xanthorrhizol resistance. The resistant clones were able to grow in LB medium containing 256 µg/mL xanthorrhizol, representing a 16-fold increase in the minimum inhibitory concentration. Subsequent DNA sequence analysis revealed that overexpression of tadA, galU, fucU, ydeA, ydaC, soxS, nrdH, yiiD, and mltF genes conferred increased resistance towards xanthorrhizol. Among these nine genes, tadA is the only essential gene. tadA encodes a tRNA-specific adenosine deaminase. Overexpression of E. coli W3110 imp4213 (pCA24N-tadA conferred resistance to xanthorrhizol up to 128 µg/mL. Moreover, overexpression of two tadA mutant enzymes (A143V and F149G led to a twofold increase in the MIC. These results suggest that the targets of xanthorrhizol may include tadA, which has never before been explored as an antibiotic target.

  17. Overexpression of Salmonella enterica serovar Typhi recA gene confers fluoroquinolone resistance in Escherichia coli DH5α.

    Science.gov (United States)

    Yassien, M A M; Elfaky, M A

    2015-11-01

    A spontaneous fluoroquinolone-resistant mutant (STM1) was isolated from its parent Salmonella enterica serovar Typhi (S. Typhi) clinical isolate. Unlike its parent isolate, this mutant has selective resistance to fluoroquinolones without any change in its sensitivity to various other antibiotics. DNA gyrase assays revealed that the fluoroquinolone resistance phenotype of the STM1 mutant did not result from alteration of the fluoroquinolone sensitivity of the DNA gyrase isolated from it. To study the mechanism of fluoroquinolone resistance, a genomic library from the STM1 mutant was constructed in Escherichia coli DH5α and two recombinant plasmids were obtained. Only one of these plasmids (STM1-A) conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. The chromosomal insert from STM1-A, digested with EcoRI and HindIII restriction endonucleases, produced two DNA fragments and these were cloned separately into pUC19 thereby generating two new plasmids, STM1-A1 and STM1-A2. Only STM1-A1 conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. Sequence and subcloning analyses of STM1-A1 showed the presence of an intact RecA open reading frame. Unlike that of the wild-type E. coli DH5α, protein analysis of a crude STM1-A1 extract showed overexpression of a 40 kDa protein. Western blotting confirmed the 40 kDa protein band to be RecA. When a RecA PCR product was cloned into pGEM-T and introduced into E. coli DH5α, the STM1-A11 subclone retained fluoroquinolone resistance. These results suggest that overexpression of RecA causes selective fluoroquinolone resistance in E. coli DH5α. PMID:26375447

  18. Overexpression of Salmonella enterica serovar Typhi recA gene confers fluoroquinolone resistance in Escherichia coli DH5α

    Directory of Open Access Journals (Sweden)

    M.A.M. Yassien

    2015-11-01

    Full Text Available A spontaneous fluoroquinolone-resistant mutant (STM1 was isolated from its parent Salmonella enterica serovar Typhi (S. Typhi clinical isolate. Unlike its parent isolate, this mutant has selective resistance to fluoroquinolones without any change in its sensitivity to various other antibiotics. DNA gyrase assays revealed that the fluoroquinolone resistance phenotype of the STM1 mutant did not result from alteration of the fluoroquinolone sensitivity of the DNA gyrase isolated from it. To study the mechanism of fluoroquinolone resistance, a genomic library from the STM1 mutant was constructed in Escherichia coli DH5α and two recombinant plasmids were obtained. Only one of these plasmids (STM1-A conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. The chromosomal insert from STM1-A, digested with EcoRI and HindIII restriction endonucleases, produced two DNA fragments and these were cloned separately into pUC19 thereby generating two new plasmids, STM1-A1 and STM1-A2. Only STM1-A1 conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. Sequence and subcloning analyses of STM1-A1 showed the presence of an intact RecA open reading frame. Unlike that of the wild-type E. coli DH5α, protein analysis of a crude STM1-A1 extract showed overexpression of a 40 kDa protein. Western blotting confirmed the 40 kDa protein band to be RecA. When a RecA PCR product was cloned into pGEM-T and introduced into E. coli DH5α, the STM1-A11 subclone retained fluoroquinolone resistance. These results suggest that overexpression of RecA causes selective fluoroquinolone resistance in E. coli DH5α.

  19. Establishing streptomycin epidemiological cut-off values for Salmonella and Escherichia coli. Microbial Drug Resistance

    NARCIS (Netherlands)

    Garcia-Migura, L.; Sunde, M.; Karlsmose, S.; Veldman, K.T.; Schroeter, A.; Guerra, B.; Granier, S.A.; Perrin-Guyomard, A.; Gicquel-Bruneau, M.; Franco, A.; Englund, S.; Teale, C.; Heiska, H.; Clemente, L.; Boerlin, P.; Moreno, M.A.; Daignault, D.; Mevius, D.J.; Hendriksen, R.S.; Aarestrup, F.M.

    2012-01-01

    This study was conducted to elucidate the accuracy of the current streptomycin epidemiological cut-off value (ECOFF) for Escherichia coli and Salmonella spp. A total of 236 Salmonella enterica and 208 E. coli isolates exhibiting MICs between 4 and 32¿mg/L were selected from 12 countries. Isolates we

  20. CTX-M Expression and Selection of Ertapenem Resistance in Klebsiella pneumoniae and Escherichia coli▿

    OpenAIRE

    Girlich, Delphine; Poirel, Laurent; Nordmann, Patrice

    2008-01-01

    In vitro selection of mutants with decreased susceptibility to ertapenem was performed using Escherichia coli and Klebsiella pneumoniae clinical strains producing either the blaCTX-M-2, blaCTX-M-3, blaCTX-M-9, or blaCTX-M-15 gene. Frequencies of mutants with decreased susceptibilities to ertapenem were similar for all β-lactamases expressed.

  1. Study of the resistance mechanisms to ultraviolet light in Escherichia Coli. III. Genetic mapping of a mutation that confers resistance to radiation

    International Nuclear Information System (INIS)

    Inside this third work with respect to the investigation of the process of adaptation of different subcultures of Escherichia coli, to the UV light, its are present the obtained results in the identification of the gene or genes implied in the resistance to UV of one of the 5 populations derived for repeated exposure to growing dose of UV light of E. coli PQ30. Those obtained data indicate that the causing mutation of the phenotype is located in a single gene, since the insert of the fragment of DNA miniTn5 in this gene, causes the lost one from the resistance and the return to the original phenotype. The gene in question is denominated radA, located in the minute 99.6 of the chromosome of E. coli and required for the efficient repair of double ruptures in the DNA. (Author)

  2. Outer membrane proteomics of kanamycin-resistant Escherichia coli identified MipA as a novel antibiotic resistance-related protein.

    Science.gov (United States)

    Li, Hui; Zhang, Dan-feng; Lin, Xiang-min; Peng, Xuan-xian

    2015-06-01

    Antibiotic-resistant bacteria are a great threat to human health and food safety and there is an urgent need to understand the mechanisms of resistance for combating these bacteria. In the current study, comparative proteomic methodologies were applied to identify Escherichia coli K-12 outer membrane (OM) proteins related to kanamycin resistance. Mass spectrometry and western blotting results revealed that OM proteins TolC, Tsx and OstA were up-regulated, whereas MipA, OmpA, FadL and OmpW were down-regulated in kanamycin-resistant E. coli K-12 strain. Genetic deletion of tolC (ΔtolC-Km) led to a 2-fold decrease in the minimum inhibitory concentration (MIC) of kanamycin and deletion of mipA (ΔmipA-Km) resulted in a 4-fold increase in the MIC of kanamycin. Changes in the MICs for genetically modified strains could be completely recovered by gene complementation. Compared with the wild-type strain, the survival capability of ΔompA-Km was significantly increased and that of Δtsx-Km was significantly decreased. We further evaluated the role and expression of MipA in response to four other antibiotics including nalidixic acid, streptomycin, chloramphenicol and aureomycin, which suggested that MipA was a novel OM protein related to antibiotic resistance.

  3. Outer membrane proteomics of kanamycin-resistant Escherichia coli identified MipA as a novel antibiotic resistance-related protein.

    Science.gov (United States)

    Li, Hui; Zhang, Dan-feng; Lin, Xiang-min; Peng, Xuan-xian

    2015-06-01

    Antibiotic-resistant bacteria are a great threat to human health and food safety and there is an urgent need to understand the mechanisms of resistance for combating these bacteria. In the current study, comparative proteomic methodologies were applied to identify Escherichia coli K-12 outer membrane (OM) proteins related to kanamycin resistance. Mass spectrometry and western blotting results revealed that OM proteins TolC, Tsx and OstA were up-regulated, whereas MipA, OmpA, FadL and OmpW were down-regulated in kanamycin-resistant E. coli K-12 strain. Genetic deletion of tolC (ΔtolC-Km) led to a 2-fold decrease in the minimum inhibitory concentration (MIC) of kanamycin and deletion of mipA (ΔmipA-Km) resulted in a 4-fold increase in the MIC of kanamycin. Changes in the MICs for genetically modified strains could be completely recovered by gene complementation. Compared with the wild-type strain, the survival capability of ΔompA-Km was significantly increased and that of Δtsx-Km was significantly decreased. We further evaluated the role and expression of MipA in response to four other antibiotics including nalidixic acid, streptomycin, chloramphenicol and aureomycin, which suggested that MipA was a novel OM protein related to antibiotic resistance. PMID:25940639

  4. Seawater is a reservoir of multi-resistant Escherichia coli, including strains hosting plasmid-mediated quinolones resistance and extended-spectrum beta-lactamases genes

    Directory of Open Access Journals (Sweden)

    Marta S. Alves

    2014-08-01

    Full Text Available The aim of this study was to examine antibiotic resistance (AR dissemination in coastal water, considering the contribution of different sources of faecal contamination. Samples were collected in Berlenga, an uninhabited island classified as Natural Reserve and visited by tourists for aquatic recreational activities. To achieve our aim, AR in Escherichia coli isolates from coastal water was compared to AR in isolates from two sources of faecal contamination: human-derived sewage and seagull faeces. Isolation of E. coli was done on Chromocult agar. Based on genetic typing 414 strains were established. Distribution of E. coli phylogenetic groups was similar among isolates of all sources. Resistances to streptomycin, tetracycline, cephalothin and amoxicillin were the most frequent. Higher rates of AR were found among seawater and faeces isolates, except for last-line antibiotics used in human medicine. Multi-resistance rates in isolates from sewage and seagull faeces (29% and 32% were lower than in isolates from seawater (39%. Seawater AR profiles were similar to those from seagull faeces and differed significantly from sewage AR profiles. Nucleotide sequences matching resistance genes blaTEM, sul1, sul2, tet(A and tet(B, were present in isolates of all sources. Genes conferring resistance to 3rd generation cephalosporins were detected in seawater (blaCTX-M-1 and blaSHV-12 and seagull faeces (blaCMY-2. Plasmid-mediated determinants of resistance to quinolones were found: qnrS1 in all sources and qnrB19 in seawater and seagull faeces. Our results show that seawater is a relevant reservoir of AR and that seagulls are an efficient vehicle to spread human-associated bacteria and resistance genes. The E. coli resistome recaptured from Berlenga coastal water was mainly modulated by seagulls-derived faecal pollution. The repertoire of resistance genes covers antibiotics critically important for humans, a potential risk for human health.

  5. Predictability of Phenotype in Relation to Common β-Lactam Resistance Mechanisms in Escherichia coli and Klebsiella pneumoniae.

    Science.gov (United States)

    Agyekum, Alex; Fajardo-Lubián, Alicia; Ai, Xiaoman; Ginn, Andrew N; Zong, Zhiyong; Guo, Xuejun; Turnidge, John; Partridge, Sally R; Iredell, Jonathan R

    2016-05-01

    The minimal concentration of antibiotic required to inhibit the growth of different isolates of a given species with no acquired resistance mechanisms has a normal distribution. We have previously shown that the presence or absence of transmissible antibiotic resistance genes has excellent predictive power for phenotype. In this study, we analyzed the distribution of six β-lactam antibiotic susceptibility phenotypes associated with commonly acquired resistance genes in Enterobacteriaceae in Sydney, Australia. Escherichia coli (n = 200) and Klebsiella pneumoniae (n = 178) clinical isolates, with relevant transmissible resistance genes (blaTEM, n = 33; plasmid AmpC, n = 69; extended-spectrum β-lactamase [ESBL], n = 116; and carbapenemase, n = 100), were characterized. A group of 60 isolates with no phenotypic resistance to any antibiotics tested and carrying none of the important β-lactamase genes served as comparators. The MICs for all drug-bacterium combinations had a normal distribution, varying only in the presence of additional genes relevant to the phenotype or, for ertapenem resistance in K. pneumoniae, with a loss or change in the outer membrane porin protein OmpK36. We demonstrated mutations in ompK36 or absence of OmpK36 in all isolates in which reduced susceptibility to ertapenem (MIC, >1 mg/liter) was evident. Ertapenem nonsusceptibility in K. pneumoniae was most common in the context of an OmpK36 variant with an ESBL or AmpC gene. Surveillance strategies to define appropriate antimicrobial therapies should include genotype-phenotype relationships for all major transmissible resistance genes and the characterization of mutations in relevant porins in organisms, like K. pneumoniae. PMID:26912748

  6. Adaptation mechanisms of Escherichia Coli to the ultraviolet light I. Isolation of mutants resistant to ultraviolet light; Mecanismos de adaptacion de Escherichia Coli a la luz ultravioleta I. Aislamiento de mutantes resistentes a luz ultravioleta

    Energy Technology Data Exchange (ETDEWEB)

    Alcantara D, D. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1995-09-15

    The objective of this work is to study the adaptation mechanisms of Escherichia coli to the ultraviolet light of 254 nm (W), a component of the solar light that induces a variety of damages in the DNA of the cells exposed, which should be eliminated in order to avoid its lethal and mutagenic effects. Inside this first report, the results obtained about the resistance to UV radiation of 5 independent populations of Escherichia coli, which were subjected in parallel form to 80 successive exposures of UV light with inserted periods of growth are reported. (Author)

  7. PREVALENCE OF SULFONAMIDE AND FLORFENICOL RESISTANCE GENES IN ESCHERICHIA COLI ISOLATED FROM YAKS (BOS GRUNNIENS) AND HERDSMEN IN THE TIBETAN PASTURE.

    Science.gov (United States)

    Zhang, Anyun; Yang, Yunfei; Wang, Hongning; Lei, Changwei; Xu, Changwen; Guan, Zhongbin; Liu, Bihui; Huang, Xi; Peng, Linyao

    2015-07-01

    To determine the antimicrobial susceptibility profiles and prevalence of resistance genes in Escherichia coli isolated from yaks (Bos grunniens) and herdsmen in nine plateau pastures in Tibet, we isolated 184 nonidentical strains of E. coli from yaks and herdsmen. Antimicrobial susceptibility testing of 15 antimicrobials was conducted and the prevalence of sulfonamide resistance genes (sul1, sul2, and sul3) and florfenicol resistance genes (floR, cfr, cmlA, fexA, pexA, and estDL136) was determined. Escherichia coli isolated from yaks had a high resistance rate to sulfamethoxazole (44%), sulphafurazole (40.4%), and florfenicol (11.4%). Escherichia coli isolated from herdsmen had a high resistance rate to sulfamethoxazole (57%) and sulphafurazole (51%). In addition, sul genes were present in 93% of sulfonamide-resistant isolates (84/90), and 17 floR genes and four cmlA genes were found in 19 florfenicol-resistant isolates. Even though florfenicol is prohibited from use in humans, three floR genes were detected in strains isolated from herdsmen. The three floR-positive isolates from herdsmen had pulsed-field gel electrophoresis patterns similar to isolates from yaks. In addition to documenting the sul and floR genes in E. coli isolated from yaks and herdsmen in the Tibetan pasture, we demonstrated the potential risk that antimicrobial-resistant E. coli could spread among herdsmen and yaks.

  8. Growth of an Aspergillus flavus transformant expressing Escherichia coli beta-glucuronidase in maize kernels resistant to aflatoxin production.

    Science.gov (United States)

    Brown, R L; Cleveland, T E; Payne, G A; Woloshuk, C P; White, D G

    1997-01-01

    Kernels of a maize inbred that demonstrated resistance to aflatoxin production in previous studies were inoculated with an Aspergillus flavus strain containing the Escherichia coli beta-D-glucuronidase reporter gene linked to a beta-tubulin gene promoter and assessed for both fungal growth and aflatoxin accumulation. Prior to inoculation, kernels were pin-wounded through the pericarp to the endosperm, pin-wounded in the embryo region, or left unwounded. After 7 days incubation with the fungus, beta-glucuronidase activity (fungal growth) in the kernels was quantified using a fluorogenic assay and aflatoxin B content of the same kernels was analyzed. Kernels of a susceptible inbred, similarly treated, served as controls. Results indicate a positive relationship between aflatoxin levels and the amount of fungal growth. However, resistant kernels wounded through the pericarp to the endosperm before inoculation supported an increase in aflatoxin B over levels observed in nonwounded kernels, without an increase in fungal growth. Wounding kernels of the resistant inbred through the embryo resulted in both the greatest fungal growth and the highest levels of aflatoxin B1 for this genotype. Maintenance of resistance to aflatoxin B1 in endosperm-wounded kernels may be due to the action of a mechanism which limits fungal access to the kernel embryo. PMID:10465048

  9. Multidrug Resistance in Escherichia coli Strains Isolated from Infections in Dogs and Cats in Poland (2007–2013

    Directory of Open Access Journals (Sweden)

    Magdalena Rzewuska

    2015-01-01

    Full Text Available The antimicrobial susceptibility of Escherichia coli isolates associated with various types of infections in dogs and cats was determined. The studied isolates were most frequently susceptible to fluoroquinolones and the extended-spectrum cephalosporins (ESCs, antimicrobials commonly used in treatment of infections in companion animals. However, an increase in the percentage of strains resistant to β-lactam antibiotics including ESCs was noted between January 2007 and December 2013. The frequency of multidrug-resistant (MDR E. coli isolation (66.8% of isolates is alarming. Moreover, the statistically significant increase of the percentage of MDR isolates was observed during the study period. No difference in the prevalence of multidrug resistance was found between bacteria causing intestinal and extraintestinal infections and between canine and feline isolates. Nonhemolytic E. coli isolates were MDR more often than hemolytic ones. Our study showed the companion animals in Poland as an important reservoir of MDR bacteria. These results indicate that continuous monitoring of canine and feline E. coli antimicrobial susceptibility is required. Furthermore, introduction and application of recommendations for appropriate use of antimicrobials in small animal practice should be essential to minimize the emergence of multidrug resistance among E. coli in companion animals.

  10. Toxic epidermal necrolysis and agranulocytosis: Rare adverse effects of ciprofloxacin

    Directory of Open Access Journals (Sweden)

    Upadya Gatha

    2009-10-01

    Full Text Available Ciprofloxacin is one of the most commonly used antibacterial agents with relatively few side effects. Serious adverse reactions reported with ciprofloxacin are rare with an incidence of 0.6%. Recently we came across two rare adverse effects of ciprofloxacin, viz. toxic epidermal necrolysis and agranulocytosis. To our knowledge, a total of seven cases have been reported in the literature documenting an association between oral ciprofloxacin administration and toxic epidermal necrolysis. One case of granulocytopenia, four of pancytopenia and fifteen of leucopenia worldwide have been reported. With the use of ciprofloxacin becoming more and more widespread, these two rare but fatal complications of ciprofloxacin should be borne in mind.

  11. Tailoring Cytotoxicity of Antimicrobial Peptidomimetics with High Activity against Multidrug-Resistant Escherichia coli

    DEFF Research Database (Denmark)

    Jahnsen, Rasmus D; Sandberg-Schaal, Anne; Vissing, Karina Juul;

    2014-01-01

    Infections with multidrug-resistant pathogens are an increasing concern for public health. Recently, subtypes of peptide-peptoid hybrids were demonstrated to display potent activity against multidrug-resistant Gram-negative bacteria. Here, structural variation of these antibacterial peptidomimetics...... cells. Thus, lead compounds with a high selectivity toward killing of clinically important multidrug-resistant E. coli were identified....

  12. Adaptive Evolution of Escherichia coli to an α-Peptide/β-Peptoid Peptidomimetic Induces Stable Resistance

    DEFF Research Database (Denmark)

    Hein-Kristensen, Line; Franzyk, Henrik; Holch, Anne;

    2013-01-01

    populations. Resistant isolates showed no cross-resistance against a panel of membrane-active AMPs. These isolates were highly susceptible to blood plasma antibacterial activity and were killed when plasma concentrations exceeded ∼30%. Notably, MIC of the peptidomimetic against resistant isolates returned...

  13. Prevalence and characteristics of quinolone resistance in Escherichia coli in veal calves

    NARCIS (Netherlands)

    Hordijk, J.; Veldman, K.T.; Dierikx, C.M.; Essen-Zandbergen, van A.; Wagenaar, J.A.; Mevius, D.J.

    2012-01-01

    Quinolone resistance is studied and reported increasingly in isolates from humans, food-producing animals and companion animals. Resistance can be caused by chromosomal mutations in topoisomerase genes, plasmid-mediated resistance genes, and active transport through efflux pumps. Cross sectional dat

  14. Genotypic Detection of Antibiotic Resistance in "Escherichia Coli.": A Classroom Exercise

    Science.gov (United States)

    Longtin, Sarah; Guilfoile, Patrick; Asper, Andrea

    2004-01-01

    Bacterial antibiotic resistance remains a problem of clinical importance. Current microbiological methods for determining antibiotic resistance are based on culturing bacteria, and may require up to 48 hours to complete. Molecular methods are increasingly being developed to speed the identification of antibiotic resistance and to determine its…

  15. Incorporation of Farnesol Significantly Increases the Efficacy of Liposomal Ciprofloxacin against Pseudomonas aeruginosa Biofilms in Vitro.

    Science.gov (United States)

    Bandara, H M H N; Herpin, M J; Kolacny, D; Harb, A; Romanovicz, D; Smyth, H D C

    2016-08-01

    The challenge of eliminating Pseudomonas aeruginosa infections, such as in cystic fibrosis lungs, remains unchanged due to the rapid development of antibiotic resistance. Poor drug penetration into dense P. aeruginosa biofilms plays a vital role in ineffective clearance of the infection. Thus, the current antibiotic therapy against P. aeruginosa biofilms need to be revisited and alternative antibiofilm strategies need to be invented. Fungal quorum sensing molecule (QSM), farnesol, appears to have detrimental effects on P. aeruginosa. Thus, this study aimed to codeliver naturally occurring QSM farnesol, with the antibiotic ciprofloxacin as a liposomal formulation to eradicate P. aeruginosa biofilms. Four different liposomes (with ciprofloxacin and farnesol, Lcip+far; with ciprofloxacin, Lcip; with farnesol, Lfar; control, Lcon) were prepared using dehydration-rehydration method and characterized. Drug entrapment and release were evaluated by spectrometry and high performance liquid chromatography (HPLC). The efficacy of liposomes was assessed using standard biofilm assay. Liposome-treated 24 h P. aeruginosa biofilms were quantitatively assessed by XTT reduction assay and crystal violet assay, and qualitatively by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Ciprofloxacin release from liposomes was higher when encapsulated with farnesol (Lcip+far) compared to Lcip (3.06% vs 1.48%), whereas farnesol release was lower when encapsulated with ciprofloxacin (Lcip+far) compared to Lfar (1.81% vs 4.75%). The biofilm metabolism was significantly lower when treated with Lcip+far or Lcip compared to free ciprofloxacin (XTT, P < 0.05). When administered as Lcip+far, the ciprofloxacin concentration required to achieve similar biofilm inhibition was 125-fold or 10-fold lower compared to free ciprofloxacin or Lcip, respectively (P < 0.05). CLSM and TEM confirmed predominant biofilm disruption, greater dead cell ratio, and increased depth of

  16. A 17-year study of bloodstream Escherichia coli infection after liver transplantation: resistance rate,risk factor and mortality%肝移植术后大肠埃希菌血行感染耐药及危险因素分析

    Institute of Scientific and Technical Information of China (English)

    邰强; 郭志勇; 黄洁夫; 何晓顺; 胡安斌; 巫林伟; 鞠卫强; 朱晓峰; 王东平; 王国栋; 马毅

    2011-01-01

    Objective To explore the resistance rate,risk factors and mortality of Escherichia coli bloodstream infections (BSI) after liver transplantation.Methods From January 1993 to May 2010,a retrospective analysis of Escherichia coli in liver transplants were conducted.Results A total of 88 BSI occurred in 83/695 patients and Escherichia coli ( n =23 ) was most commonly found.Carbapenem and piperacillin-tazobactam were the most consistently active against Escherichia coli while the resistance rate to enterococcus for ciprofloxacin,gentamycin,ampicillin-clavulanic acid was over 60%.Univariate analysis identified the following variables as risk factors for Escherichia coli bacteremia:cholangioenterostomy ( P <0.001 ) and ductal complications ( P < 0.001 ).Escherichia coli bloodstream infection could increase the mortality at 15 days after bloodstream infection.No significant difference in mortality occurred at 30 days and 1 year after enterococcal bacteremia.Conclusion Escherichia coli after liver transplantation is resistant to agents but commonly active to carbapenem and piperacillin-tazobactam.The risk factor associated with Escherichia coli bloodstream infections are cholangioenterostomy and ductal complications.Escherichia coli bloodstream infection can increase the mortality at 15 days after bloodstream infection.%目的 探讨肝移植术后血行感染中大肠埃希菌的耐药、临床结果及危险因素.方法 回顾分析1993年1月至2010年5月,中山大学附属第一医院移植科肝移植术后血行感染中大肠埃希菌患者资料,对患者的资料(如:抗生素耐药、术式及危险因素)进行分类统计.结果 695例肝移植患者中,83例(7.6%)88次出现革兰阴性球菌血行感染,以大肠埃希菌(23例)最为常见.大肠埃希菌对碳青酶烯类抗生素均为100%敏感,对哌拉西林/他唑巴坦耐药率在5%以下,而对环丙沙星、庆大霉素、氨苄西林/克拉维酸耐药率基本都在60%以上.针

  17. Anti - microbial resistance stratified by risk factor among Escherichia coli strains isolated from the urinary tract at a rural clinic in Central India

    Directory of Open Access Journals (Sweden)

    Chatterjee B

    2009-01-01

    Full Text Available Background: The failure of empirical therapy is frequently observed, even in community-acquired urinary tract infections. We, therefore, conducted a prospective, clinic-based study in 2004-2005 to document anti-microbial resistance rates and correlate them with possible risk factors to assist empirical decision-making. Materials and Methods: Symptomatic patients with pyuria underwent urine culture. Isolates were identified using standard methods and anti-microbial resistance was determined by disk-diffusion. Ultrasonography was used to detect complicating factors. Patients were stratified by the presence of complicating factors and history of invasive procedures for comparison of resistance rates. Statistical Method Used: Chi-square or Fisher exact tests, as appropriate. Results: There were 156 E. coli isolates, of which 105 were community-acquired. Twenty-three community-acquired isolates were from patients with complicating factors while 82 were from patients without any. Fifty-one isolates were from patients who had recently undergone invasive procedures on the urinary tract. Thirty-two community-acquired isolates from reproductive-age women without apparent complicating factors had resistance rates of 50% or above against tetracyclines, Co-trimoxazole, aminopenicillins, Nalidixic acid, Ciprofloxacin and 1 st generation cephalosporins. Resistance rates were significantly higher among isolates from patients subjected to invasive procedures, except against Co-trimoxazole, tetracyclines and Amikacin. Conclusion: High rates of anti-microbial resistance in community-acquired uropathogens have made antimicrobial sensitivity testing necessary even in a rural, primary-care setting.

  18. Role of tetracycline speciation in the bioavailability to Escherichia coli for uptake and expression of antibiotic resistance.

    Science.gov (United States)

    Zhang, Yingjie; Boyd, Stephen A; Teppen, Brian J; Tiedje, James M; Li, Hui

    2014-05-01

    Tetracycline contains ionizable functional groups that manifest several species with charges at different locales and differing net charge; the fractional distribution of each species depends on pH-pKa relationship in the aqueous phase. In nature, these species interact with naturally abundant cations (e.g., Ca(2+) and Mg(2+)) to form metal-tetracycline complexes in water. In this study, we used Escherichia coli MC4100/pTGM whole-cell bioreporter to investigate tetracycline uptake from solution under varying conditions of pH, salt composition and concentration by quantifying the corresponding expression of antibiotic resistance gene. The expression of antibiotic resistance gene in the E. coli bioreporter responded linearly to intracellular tetracycline concentration. Less tetracycline entered E. coli cells at solution pH of 8.0 than at pH 6.0 or 7.0 indicating reduced bioavailability of the antibiotic at higher pH. Both Mg(2+) and Ca(2+) in solution formed metal-tetracycline complexes which reduced uptake of tetracycline by E. coli hence diminishing the bioresponse. Among the various tetracycline species present in solution, including both metal-complexed and free (noncomplexed) species, zwitterionic tetracycline was identified as the predominant species that most readily passed through the cell membrane eliciting activation of the antibiotic resistance gene in E. coli. The results indicate that the same total concentration of tetracycline in ambient solution can evoke very different expression of antibiotic resistance gene in the exposed bacteria due to differential antibiotic uptake. Accordingly, geochemical factors such as pH and metal cations can modulate the selective pressure exerted by tetracycline for development and enrichment of antibiotic resistant bacteria. We suggest that tetracycline speciation analysis should be incorporated into the risk assessment framework for evaluating environmental exposure and the corresponding development of antibiotic

  19. Effect of ethnomedicinal plants used in folklore medicine in Jordan as antibiotic resistant inhibitors on Escherichia coli

    Directory of Open Access Journals (Sweden)

    Aburjai Talal A

    2010-02-01

    Full Text Available Abstract Background Escherichia coli occurs naturally in the human gut; however, certain strains that can cause infections, are becoming resistant to antibiotics. Multidrug-resistant E. coli that produce extended-spectrum β lactamases (ESBLs, such as the CTX-M enzymes, have emerged within the community setting as an important cause of urinary tract infections (UTIs and bloodstream infections may be associated with these community-onsets. This is the first report testing the antibiotic resistance-modifying activity of nineteen Jordanian plants against multidrug-resistant E. coli. Methods The susceptibility of bacterial isolates to antibiotics was tested by determining their minimum inhibitory concentrations (MICs using a broth microdilution method. Nineteen Jordanian plant extracts (Capparis spinosa L., Artemisia herba-alba Asso, Echinops polyceras Boiss., Gundelia tournefortii L, Varthemia iphionoides Boiss. & Blanche, Eruca sativa Mill., Euphorbia macroclada L., Hypericum trequetrifolium Turra, Achillea santolina L., Mentha longifolia Host, Origanum syriacum L., Phlomis brachydo(Boiss. Zohary, Teucrium polium L., Anagyris foetida L., Trigonella foenum-graecum L., Thea sinensis L., Hibiscus sabdariffa L., Lepidium sativum L., Pimpinella anisum L. were combined with antibiotics, from different classes, and the inhibitory effect of the combinations was estimated. Results Methanolic extracts of the plant materials enhanced the inhibitory effects of chloramphenicol, neomycin, doxycycline, cephalexin and nalidixic acid against both the standard strain and to a lesser extent the resistant strain of E. coli. Two edible plant extracts (Gundelia tournefortii L. and Pimpinella anisum L. generally enhanced activity against resistant strain. Some of the plant extracts like Origanum syriacum L.(Labiateae, Trigonella foenum- graecum L.(Leguminosae, Euphorbia macroclada (Euphorbiaceae and Hibiscus sabdariffa (Malvaceae did not enhance the activity of

  20. In vitro and in vivo evaluation of [{sup 18}F]ciprofloxacin for the imaging of bacterial infections with PET

    Energy Technology Data Exchange (ETDEWEB)

    Langer, Oliver; Brunner, Martin; Zeitlinger, Markus; Mueller, Ulrich; Lackner, Edith; Joukhadar, Christian; Mueller, Markus [Medical University Vienna, Division of Clinical Pharmacokinetics, Department of Clinical Pharmacology, Vienna (Austria); Ziegler, Sophie; Minar, Erich [Medical University Vienna, Division of Angiology, Department of Internal Medicine II, Vienna (Austria); Dobrozemsky, Georg [Medical University Vienna, Department of Nuclear Medicine, Vienna (Austria); Medical University Vienna, Department of Biomedical Engineering and Physics, Vienna (Austria); Mitterhauser, Markus; Wadsak, Wolfgang; Dudczak, Robert; Kletter, Kurt [Medical University Vienna, Department of Nuclear Medicine, Vienna (Austria)

    2005-02-01

    The suitability of the{sup 18}F-labelled fluoroquinolone antibiotic ciprofloxacin ([{sup 18}F]ciprofloxacin) for imaging of bacterial infections with positron emission tomography (PET) was assessed in vitro and in vivo. For the in vitro experiments, suspensions of various E. colistrains were incubated with different concentrations of [{sup 18}F]ciprofloxacin (0.01-5.0 {mu}g/ml) and radioactivity retention was measured in a gamma counter. For the in vivo experiments, 725 {+-} 9 MBq [{sup 18}F]ciprofloxacin was injected intravenously into four patients with microbiologically proven bacterial soft tissue infections of the lower extremities and time-radioactivity curves were recorded in infected and uninfected tissue for 5 h after tracer injection. Binding of [{sup 18}F]ciprofloxacin to bacterial cells was rapid, non-saturable and readily reversible. Moreover, bacterial binding of the agent was similar in ciprofloxacin-resistant and ciprofloxacin-susceptible clinical isolates. These findings suggest that non-specific binding rather than specific binding to bacterial type II topoisomerase enzymes is the predominant mechanism of bacterial retention of the radiotracer. PET studies in the four patients with microbiologically proven bacterial soft tissue infections demonstrated locally increased radioactivity uptake in infected tissue, with peak ratios between infected and uninfected tissue ranging from 1.8 to 5.5. Radioactivity was not retained in infected tissue and appeared to wash out with a similar elimination half-life as in uninfected tissue, suggesting that the kinetics of [{sup 18}F]ciprofloxacin in infected tissue are governed by increased blood flow and vascular permeability due to local infection rather than by a binding process. Taken together, our results indicate that [{sup 18}F]ciprofloxacin is not suited as a bacteria-specific infection imaging agent for PET. (orig.)

  1. In vitro and in vivo evaluation of [18F]ciprofloxacin for the imaging of bacterial infections with PET

    International Nuclear Information System (INIS)

    The suitability of the18F-labelled fluoroquinolone antibiotic ciprofloxacin ([18F]ciprofloxacin) for imaging of bacterial infections with positron emission tomography (PET) was assessed in vitro and in vivo. For the in vitro experiments, suspensions of various E. colistrains were incubated with different concentrations of [18F]ciprofloxacin (0.01-5.0 μg/ml) and radioactivity retention was measured in a gamma counter. For the in vivo experiments, 725 ± 9 MBq [18F]ciprofloxacin was injected intravenously into four patients with microbiologically proven bacterial soft tissue infections of the lower extremities and time-radioactivity curves were recorded in infected and uninfected tissue for 5 h after tracer injection. Binding of [18F]ciprofloxacin to bacterial cells was rapid, non-saturable and readily reversible. Moreover, bacterial binding of the agent was similar in ciprofloxacin-resistant and ciprofloxacin-susceptible clinical isolates. These findings suggest that non-specific binding rather than specific binding to bacterial type II topoisomerase enzymes is the predominant mechanism of bacterial retention of the radiotracer. PET studies in the four patients with microbiologically proven bacterial soft tissue infections demonstrated locally increased radioactivity uptake in infected tissue, with peak ratios between infected and uninfected tissue ranging from 1.8 to 5.5. Radioactivity was not retained in infected tissue and appeared to wash out with a similar elimination half-life as in uninfected tissue, suggesting that the kinetics of [18F]ciprofloxacin in infected tissue are governed by increased blood flow and vascular permeability due to local infection rather than by a binding process. Taken together, our results indicate that [18F]ciprofloxacin is not suited as a bacteria-specific infection imaging agent for PET. (orig.)

  2. Potentiation of antimicrobial activity of ciprofloxacin by Pelargonium graveolens essential oil against selected uropathogens.

    Science.gov (United States)

    Malik, Tripti; Singh, Padma; Pant, Shailja; Chauhan, Nirpendra; Lohani, Hema

    2011-08-01

    The recent approach of using herbs and antibiotics in combination constitutes a strategy to overcome the problems of resistance and side effects associated with conventional antibiotics. In the present study, the antimicrobial effect of Pelargonium graveolens L' Hér essential oil in combination with ciprofloxacin was evaluated on uropathogens, namely, Klebsiella pneumoniae KT2, Proteus mirabilis PRT3 and Staphylococcus aureus ST2. Minimum inhibitory concentrations of P. graveolens essential oil and ciprofloxacin were determined by the microbroth dilution method and further, the interaction between these two agents was studied by a checkerboard method. The fractional inhibitory concentration index (FICI) was calculated to be 0.375 for both K. pneumoniae KT2 and P. mirabilis PRT3, while for S. aureus ST2 it was found to be 0.5. The values of FICI for the tested microorganisms were found to be ≤0.5, which indicates synergism between P. graveolens essential oil and ciprofloxacin. The concave shaped curve in the isobolograms also depicted a synergistic effect of P. graveolens essential oil and ciprofloxacin against the tested microorganisms. Hence, the synergistic action of P. graveolens essential oil and ciprofloxacin may be applied for the treatment of UTIs, which have hitherto been treated by using only synthetic drugs.

  3. Efficacy of Poly-Lactic-Co-Glycolic Acid Micro- and Nanoparticles of Ciprofloxacin Against Bacterial Biofilms.

    Science.gov (United States)

    Thomas, Nicky; Thorn, Chelsea; Richter, Katharina; Thierry, Benjamin; Prestidge, Clive

    2016-10-01

    Bacterial biofilms are associated with a number of recurring infectious diseases and are a major cause for antibiotic resistance. Despite the broad use of polymeric microparticles and nanoparticles in biomedical research, it is not clear which particle size is more effective against biofilms. The purpose of this study was to evaluate the efficacy of sustained release poly-lactic-co-glycolic acid (PLGA) micro- and nanoparticles containing ciprofloxacin against biofilms of Staphylococcus aureus and Pseudomonas aeruginosa. The PLGA particles were prepared by the double emulsion solvent evaporation method. The resulting microparticles (12 μm) and nanoparticles (300 nm) contained drug loads of 7.3% and 4.5% (wt/wt) ciprofloxacin, respectively. Drug release was complete within 1 week following comparable release profiles for both particle sizes. Micro- and nanoparticles demonstrated a similar in vitro antibiofilm performance against mature P aeruginosa and S aureus with marked differences between the 2 strains. The sustained release of ciprofloxacin from micro- and nanoparticles over 6 days was equally effective as the continuous treatment with ciprofloxacin solution over the same period resulting in the eradication of culturable S aureus suggesting that reformulation of ciprofloxacin as sustained release PLGA micro- and nanoparticles might be valuable formulation approaches for the treatment of biofilms. PMID:27519649

  4. Plasmid-mediated quinolone resistance determinants in quinolone-resistant Escherichia coli isolated from patients with bacteremia in a university hospital in Taiwan, 2001-2015.

    Science.gov (United States)

    Kao, Cheng-Yen; Wu, Hsiu-Mei; Lin, Wei-Hung; Tseng, Chin-Chung; Yan, Jing-Jou; Wang, Ming-Cheng; Teng, Ching-Hao; Wu, Jiunn-Jong

    2016-01-01

    The aim of this study was to characterize fluoroquinolone (FQ)-resistant Escherichia coli isolates from bacteremia in Taiwan in 2001-2015. During the study period, 248 (21.2%) of 1171 isolates were identified as levofloxacin-resistant. The results of phylogenetic group analysis showed that 38.7% of the FQ-resistant isolates belonged to phylogenetic group B2, 23.4% to group B1, 22.6% to groupA, 14.9% to group D, and 0.4% belonged to group F. FQ-resistant isolates were highly susceptible to cefepime (91.5%), imipenem (96.0%), meropenem (98.8%), amikacin (98.0%), and fosfomycin (99.6%), as determined by the agar dilution method. β-lactamases, including blaTEM (66.1%), blaCMY-2 (16.5%), blaCTX-M (5.2%), blaDHA-1 (1.6%), and blaSHV-12 (1.6%), were found in FQ-resistant isolates. The results of PCR and direct sequencing showed that 37 isolates (14.9%) harbored plasmid-mediated quinolone resistance (PMQR) genes. qnrB2, qnrB4, qnrS1, coexistence of qnrB4 and qnrS1, oqxAB, and aac(6')-Ib-cr were found in 1, 4, 4, 1, 15, and 14 isolates, respectively. PMQR genes were successfully transfered for 11 (29.7%) of the 37 PMQR-harboring isolates by conjugation to E. coli C600. These findings indicate that qnr genes remained rare in E. coli but demonstrate the potential spread of oqxAB and aac(6')-Ib-c in Taiwan. PMID:27573927

  5. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production.

    Science.gov (United States)

    Mo, Solveig Sølverød; Slettemeås, Jannice Schau; Berg, Einar Sverre; Norström, Madelaine; Sunde, Marianne

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the blaCMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare blaCMY-2 containing Escherichia coli isolated from the intestinal flora of broilers and retail chicken meat (fillets) to identify possible successful clones and/or resistance plasmids widespread in the Norwegian broiler production. Methods used included PCR based phylotyping, conjugation experiments, plasmid replicon typing, pulsed-field gel electrophoresis, multiple locus variable-number tandem-repeats analysis and whole genome sequencing. The nucleotide sequence of an IncK plasmid carrying blaCMY-2 was determined. Intestinal isolates displayed a higher degree of genetic diversity than meat isolates. A cluster of genetically related isolates belonging to ST38, phylogroup D, carrying blaCMY-2 containing IncK plasmids was identified. Furthermore, genes encoding plasmid stability systems (relBE/stbDE and pndAC) were identified on the IncK plasmid. Single nucleotide polymorphism (SNP) analysis of a subset of isolates confirmed a close genetic relationship within the two most prevalent STs. The IncK plasmids within these two STs also shared a high degree of similarity. Cephalosporin-resistant E. coli with the same genetic characteristics have been identified in the broiler production in other European countries, and the IncK plasmid characterized in this study showed close homology to a plasmid isolated from retail chicken meat in the Netherlands. The results indicate that both clonal expansion and horizontal transfer of blaCMY-2 containing plasmids contribute to dissemination of cephalosporin resistant E. coli in the broiler production. The presence of plasmid

  6. Plasmid and Host Strain Characteristics of Escherichia coli Resistant to Extended-Spectrum Cephalosporins in the Norwegian Broiler Production.

    Science.gov (United States)

    Mo, Solveig Sølverød; Slettemeås, Jannice Schau; Berg, Einar Sverre; Norström, Madelaine; Sunde, Marianne

    2016-01-01

    Escherichia coli resistant to extended-spectrum cephalosporins have been detected in the Norwegian broiler production, despite the fact that antimicrobial agents are rarely used. The genetic mechanism responsible for cephalosporin resistance is mainly attributed to the presence of the blaCMY-2 gene encoding a plasmid-mediated AmpC-beta-lactamase (pAmpC). The aim of this study was to characterize and compare blaCMY-2 containing Escherichia coli isolated from the intestinal flora of broilers and retail chicken meat (fillets) to identify possible successful clones and/or resistance plasmids widespread in the Norwegian broiler production. Methods used included PCR based phylotyping, conjugation experiments, plasmid replicon typing, pulsed-field gel electrophoresis, multiple locus variable-number tandem-repeats analysis and whole genome sequencing. The nucleotide sequence of an IncK plasmid carrying blaCMY-2 was determined. Intestinal isolates displayed a higher degree of genetic diversity than meat isolates. A cluster of genetically related isolates belonging to ST38, phylogroup D, carrying blaCMY-2 containing IncK plasmids was identified. Furthermore, genes encoding plasmid stability systems (relBE/stbDE and pndAC) were identified on the IncK plasmid. Single nucleotide polymorphism (SNP) analysis of a subset of isolates confirmed a close genetic relationship within the two most prevalent STs. The IncK plasmids within these two STs also shared a high degree of similarity. Cephalosporin-resistant E. coli with the same genetic characteristics have been identified in the broiler production in other European countries, and the IncK plasmid characterized in this study showed close homology to a plasmid isolated from retail chicken meat in the Netherlands. The results indicate that both clonal expansion and horizontal transfer of blaCMY-2 containing plasmids contribute to dissemination of cephalosporin resistant E. coli in the broiler production. The presence of plasmid

  7. Effective Phages as Green Antimicrobial Agents Against Antibiotic-Resistant Hospital Escherichia coli

    OpenAIRE

    Rahmani, Rana; Zarrini, Gholamreza; Sheikhzadeh, Farzam; Aghamohammadzadeh, Naser

    2015-01-01

    Background: Bacteriophages are viruses that attack bacteria and lead to their lysis in an efficient and highly specific manner. These natural enemies of bacteria were used as therapeutic agents before the advent of antibiotics. Currently, with the rapid spread of multi-drug resistant bacteria, phage therapy can be an effective alternative treatment for antibiotic resistant bacteria. Objectives: This study evaluated the effectiveness of bacteriophages in removing antibiotic-resistant clinical ...

  8. Surveillance and Detection of Inhibitor-Resistant Beta-Lactamases in Clinical Isolates of Escherichia coli

    OpenAIRE

    Carl Urban; Patricia Bradford; Joseph Villarin

    2007-01-01

    In recent years, resistance to beta-lactam antibiotics, such as the widely-used cephalosporins and penicillins, has become a major challenge for disease therapy, particularly in common hospital-acquired infections. In the search for the mechanisms behind this increasingly prevalent form of resistance, microbiologists have identified a new type of beta-lactamase enzyme, called inhibitor-resistant TEMs (IRTs), which can withstand the effects of beta-lactamase inhibitor compounds, further reduci...

  9. Differential epigenetic compatibility of qnr antibiotic resistance determinants with the chromosome of Escherichia coli

    OpenAIRE

    María B Sánchez; Martínez, José L.

    2012-01-01

    Environmental bacteria harbor a plethora of genes that, upon their horizontal transfer to new hosts, may confer resistance to antibiotics, although the number of such determinants actually acquired by pathogenic bacteria is very low. The founder effect, fitness costs and ecological connectivity all influence the chances of resistance transfer being successful. We examined the importance of these bottlenecks using the family of quinolone resistance determinants Qnr. The results indicate the ep...

  10. High prevalence of multidrug resistance and random distribution of mobile genetic elements among uropathogenic Escherichia coli (UPEC) of the four major phylogenetic groups.

    Science.gov (United States)

    Rijavec, Matija; Starcic Erjavec, Marjanca; Ambrozic Avgustin, Jerneja; Reissbrodt, Rolf; Fruth, Angelika; Krizan-Hergouth, Veronika; Zgur-Bertok, Darja

    2006-08-01

    One hundred and ten UTI Escherichia coli strains, from Ljubljana, Slovenia, were analyzed for antibiotic resistances, mobile DNA elements, serotype, and phylogenetic origin. A high prevalence of drug resistance and multidrug resistance was found. Twenty-six percent of the isolates harbored a class 1 integron, while a majority of the strains (56%) harbored rep sequences characteristic of F-like plasmids. int as well as rep sequences were found to be distributed in a random manner among strains of the four major phylogenetic groups indicating that all groups have a similar tendency to acquire and maintain mobile genetic elements frequently associated with resistance determinants.

  11. Imaging prostatitis with Tc-99m ciprofloxacin

    International Nuclear Information System (INIS)

    Aim: Tc-99m ciprofloxacin (Infecton) imaging was developed to discriminate infection from inflammation. It claims to show an area of viable, proliferating bacterial population that is actively using DNA gyrase, which the ciprofloxacin inhibits. The application of this imaging has been reported in patients with infected arthroplasty, soft tissue infection, pelvic inflammatory diseases, etc. Clinical evaluation with conventional urological laboratory tests often provides insufficient data in differentiating chronic bacterial prostatitis (CBP) from pelvic pain syndrome, which causes inappropriate or inadequate antibiotic therapy without definite evidence of presence or absence of bacterial infection. Therefore, we investigated the diagnostic value of the Tc-99m ciprofloxacin imaging for CBP by comparing the results of the imaging with those from the conventional tests. Materials and Methods: We custom-formulated a Tc-99m ciprofloxacin kit. We used stannous tartrate for a reducing agent in making the kit. SPECT images of the region of interest were obtained at 3 hours after injection of the radiopharmaceutical. For positive control, we imaged 2 patients: acute prostatitis and urethritis. Then the actual study included 20 subjects. We excluded from the study the patients who had received antibiotic therapy within 6 weeks. The conventional tests included CBC, urinalysis, 4-glass tests, microscopic examination of expressed prostatic secretion, bacterial culture, or PCR for chlamydia trachomatis. Kappa statistics were obtained for comparison of the two tests. Results: By conventional tests, there were 10 subjects with CBP and 10 normal subjects. The typical pattern in the Tc-99m ciprofloxacin imaging indicating CBP was the increased uptake around the prostatic urethra. Five of the 10 subjects with CBP diagnosed by conventional tests showed the increased uptake to be positive cases in the Tc-99m ciprofloxacin imaging. Of the 10 subjects diagnosed as normal by the

  12. Prevalence and Risk Factors for Colonization With Extended-Spectrum Cephalosporin-Resistant Escherichia coli in Children Attending Daycare Centers : A Cohort Study in the Netherlands

    NARCIS (Netherlands)

    Koningstein, Maike; Leenen, Margriet A; Mughini-Gras, Lapo; Scholts, Rianne M C; van Huisstede-Vlaanderen, Kirstin W; Enserink, Remko; Zuidema, Rody; Kooistra-Smid, Mirjam A M D; Veldman, Kees; Mevius, Dik; van Pelt, Wilfrid

    2015-01-01

    BACKGROUND: The purpose of this study was to determine the prevalence and risk factors for colonization with extended-spectrum cephalosporin-resistant (ESC-R) Escherichia coli in daycare center (DCC)-attending children. METHODS: This is a prospective cohort study including 44 DCCs in the Netherlands

  13. Relation between tetR and tetA expression in tetracycline resistant Escherichia coli

    DEFF Research Database (Denmark)

    Møller, Thea S. B.; Overgaard, Martin; Nielsen, Søren S.;

    2016-01-01

    Background: Tetracyclines are among the most used antibiotics in livestock worldwide. Resistance is widely disseminated in Escherichia coli, where it is generally mediated by tetracycline efflux pumps, such as TetA. Expression of tetracycline efflux pumps is tightly controlled by the repressor Te...

  14. Isolation of Escherichia coli rpoB mutants resistant to killing by lambda cII protein and altered in pyrE gene attenuation

    DEFF Research Database (Denmark)

    Hammer, Karin; Jensen, Kaj Frank; Poulsen, Peter;

    1987-01-01

    Escherichia coli mutants simultaneously resistant to rifampin and to the lethal effects of bacteriophage lambda cII protein were isolated. The sck mutant strains carry alterations in rpoB that allow them to survive cII killing (thus the name sck), but that do not impair either the expression of c...

  15. Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains Isolated from Farm Animals from 1999 to 2002: Report from the Japanese Veterinary Antimicrobial Resistance Monitoring Program

    OpenAIRE

    Kojima, Akemi; Ishii, Yoshikazu; Ishihara, Kanako; Esaki, Hidetake; Asai, Tetsuo; Oda, Chitose; Tamura, Yutaka; Takahashi, Toshio; Yamaguchi, Keizo

    2005-01-01

    A nationwide surveillance for antimicrobial susceptibility in Escherichia coli strains isolated from food-producing animals in Japan was conducted from 1999 to 2002. Eighteen cefazolin-resistant E. coli strains were isolated from broilers. Six were CTX-M-type producing, and eight were CMY-2 producing, while eight had mutations at the ampC promoter region.

  16. What is the best method? Recovery of methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamase-producing Escherichia coli from inanimate hospital surfaces.

    Science.gov (United States)

    Claro, Tânia; Galvin, Sandra; Cahill, Orla; Fitzgerald-Hughes, Deirdre; Daniels, Stephen; Humphreys, Hilary

    2014-07-01

    Environmental sampling in hospitals, when required, needs to be reliable. We evaluated different methods of sampling methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamase-producing Escherichia coli on 5 materials of the hospital setting. Petrifilms and contact plates were superior to swabs for all of the surfaces studied.

  17. Emissions of Escherichia coli Carrying Extended-Spectrum β-Lactamase Resistance from Pig Farms to the Surrounding Environment

    Directory of Open Access Journals (Sweden)

    Lili Gao

    2015-04-01

    Full Text Available The dissemination of extended-spectrum β-lactamase (ESBL-producing Escherichia coli (E. coli from food-producing animals to the surrounding environment has attracted much attention. To determine the emissions of ESBL-producing E. coli from pig farms to the surrounding environment, fecal and environmental samples from six pig farms were collected. In total, 119 ESBL-producing E. coli were isolated from feces, air samples, water, sludge and soil samples. Antibiotic susceptibility testing showed that the ESBL-producing isolates were resistant to multiple antibiotics and isolates of different origin within the same farm showed similar resistance phenotypes. Both CTX-M and TEM ESBL-encoding genes were detected in these isolates. CTX-M-14 and CTX-M-15 were the predominant ESBL genes identified. ESBL producers from feces and environmental samples within the same farm carried similar CTX-M types. The results indicated that the ESBL-producing E. coli carrying multidrug resistance could readily disseminate to the surrounding environment.

  18. Variable tellurite resistance profiles of clinically-relevant Shiga toxin-producing Escherichia coli (STEC) influence their recovery from foodstuffs.

    Science.gov (United States)

    Kerangart, Stéphane; Douëllou, Thomas; Delannoy, Sabine; Fach, Patrick; Beutin, Lothar; Sergentet-Thévenot, Delphine; Cournoyer, Benoit; Loukiadis, Estelle

    2016-10-01

    Tellurite (Tel)-amended selective media and resistance (Tel-R) are widely used for detecting Shiga toxin-producing Escherichia coli (STEC) from foodstuffs. Tel-R of 81 O157 and non-O157 STEC strains isolated from animal, food and human was thus investigated. Variations of STEC tellurite minimal inhibitory concentration (MIC) values have been observed and suggest a multifactorial and variable tellurite resistome between strains. Some clinically-relevant STEC were found highly susceptible and could not be recovered using a tellurite-based detection scheme. The ter operon was highly prevalent among highly Tel-R STEC but was not always detected among intermediately-resistant strains. Many STEC serogroup strains were found to harbor sublines showing a gradient of MIC values. These Tel-R sublines showed statistically significant log negative correlations with increasing tellurite concentration. Whatever the tellurite concentration, the highest number of resistant sublines was observed for STEC belonging to the O26 serogroup. Variations in the number of these Tel-R sublines could explain the poor recovery of some STEC serogroups on tellurite-amended media especially from food products with low levels of contamination. Comparison of tellurite MIC values and distribution of virulence-related genes showed Tel-R and virulence to be related.

  19. Molecular Epidemiology of ESBL Genes and Multi-Drug Resistance in Diarrheagenic Escherichia Coli Strains Isolated from Adults in Iran.

    Science.gov (United States)

    Ghorbani-Dalini, Sadegh; Kargar, Mohammad; Doosti, Abbas; Abbasi, Pejman; Sarshar, Meysam

    2015-01-01

    Resistance to oxyimino cephalosporins antibiotics in Enterobacteriaceae is primarily done by the extended spectrum β-lactamases (ESBLs). Clear identification of risk factors for ESBLs-producing infections is necessary. Therefore, efficient strategies can be developed to decrease outbreak of these infections. The aim of this study was to determine the antibacterial susceptibility and ESBLs pattern of diarrhogenic Escherichia coli (E. coli) strains isolated from adult patients. In the present study, diarrheogenic E. coli strains were isolated from 54 patients from the University of Medical Sciences hospitals in Shiraz. Antimicrobial susceptibility testing was done by disk diffusion method by CLSI criteria. The presence of bla TEM , bla SHV and bla CTX-M genes was investigated by PCR using designated primers. The prevalence of ESBLs-producer E. coli strains was 12.96%. Antimicrobial resistance testing showed a high resistance to cefexime, trimethoprim-sulfamethoxazole, ampicillin and penicillin. Overall, β-lactamase genes were identified in 52 (96.30%) isolates which were identified as 45 (83.33%) bla TEM, 17 (31.48%) blaSHV and 11 (20.37%) blaCTX-M. ESBLs-producer E. coli is very prevalent in Diarrheogenic strains isolated from adult patients. Also, this study clearly showed that the bla TEM gene for ESBLs-producer E. coli was widespread in Iran.

  20. Prevalence of beta-lactamases among ampicillin-resistant Escherichia coli and Salmonella isolated from food animals in Denmark

    DEFF Research Database (Denmark)

    Olesen, Inger; Hasman, Henrik; Aarestrup, Frank Møller

    2004-01-01

    The genetic background for beta-lactamase-mediated resistance to beta-lactam antibiotics was examined by PCR and sequencing in 160 ampicillin-resistant isolates (109 Escherichia coli and 51 Salmonella) obtained from healthy and diseased food animals in Denmark. Sequencing revealed three different...... variants of bla(TEM-1), of which bla(TEM-1b) was the most frequently detected (80 E. coli and 47 Salmonella), followed by bla(TEM-1a) (eight E. coli, one Salmonella) and bla(TEM-1c) (seven E. coli). A few isolates were found to express OXA, TEM-30, or PSE beta-lactamases. Mutations in the ampC promoter...... leading to increased production of the AmpC beta-lactamase were demonstrated in 11 cefoxitin-resistant or intermediate E. coli isolates. Nine of these isolates did not contain any bla(TEM) genes, whereas the remaining two did. No genes encoding SHV or extended-spectrum beta-lactamases were detected. Two...

  1. Comparative Research on Serogroups Distribution and Antimicrobial Resistance of Escherichia coil Isolates from Poultry in Different Areas of China

    Institute of Scientific and Technical Information of China (English)

    SONG Li; FENG Zhong-wu; NING Yi-bao; ZHANG Xiu-ying; SHENG Qing-chun; ZHANG Guang-chuan; LIN Shu-mao; WU Hao-ting; ZHAO Hui; GAO Guang

    2008-01-01

    A total of 241 Escherichia coli(E. coli)isolates from 349 avian samples(292 from cloacae,29 from feed and water,28 from dust and padding)were collected from Northeast,South,North,and Central China in recent years.The percentage of isolation was 69.1%.There are 67 serogroups each with 1-2 isolates distributed in different regions.and some of these regions had the preponderant serogroups.Antimicrobial-resistance(AR)of E. coli was so severe that the majority were multi-AR.Fifty percent strains were resistant to 10-19 antimicrobial drugs.Overall,the isolates represented resistance to nalidixic acid(88.1%),tetracycline(85.7%),sulfamethoxazole(81.0%),trimethoprim-sulfamethpxazole(77.1%),ampicillin (76.2%),amoxilline(74.3%),streplomycin(66.2%),fluoroquinolones(57.1-66.7%),chloramphenicol(52.9%),gentamicin (39.0%),and kanamycin(36.2%).The isolates were sensitive to cefalexin,amoxilline-clavulanic acid,amikacin,and florfenicol with all AR rate of 0-19.5%only.The results showed that the AR was more severe in chicken farms in which the antibiotics were used broadly and repeatedly.This study indicated the AR characterization of E. coli in different areas of China.It will be a foundation for studying AR mechanism and regulating the usage of antimicrobial in the poultry industry.

  2. Cefoxitin resistance mediated by loss of a porin in clinical strains of Klebsiella pneumoniae and Escherichia coli

    Directory of Open Access Journals (Sweden)

    Ananthan S

    2005-01-01

    Full Text Available PURPOSE: Porins are outer membrane protein (OMP that form water filled channels that permit the diffusion of small hydrophilic solutes like -lactam antibiotics across the outer membrane. Two major porins that facilitate diffusion of antimicrobials have been described in Klebsiella spp. and Escherichia coli. The present study was carried out to examine the role of porins among Extended Spectrum -Lactamase (ESBL and AmpC -Lactamase positive strains of Klebsiella spp. and E.coli. METHODS: Preparation of OMP from phenotypically characterized clinical isolates K.pneumoniae and E.coli and the separation of the proteins by sodium dodecyl sulfate - polyacrylamide gel electrophoresis were performed as per a previously described procedure. RESULTS: OMP analysis revealed that cefoxitin and ceftazidime resistance was mediated by loss of a porin Omp K35 in the isolates of K.pneumoniae and E.coli. CONCLUSIONS: Loss of porin mediated resistance mechanism against cefoxitin was observed among the multidrug resistant K.pneumoniae and E.coli.

  3. Variable tellurite resistance profiles of clinically-relevant Shiga toxin-producing Escherichia coli (STEC) influence their recovery from foodstuffs.

    Science.gov (United States)

    Kerangart, Stéphane; Douëllou, Thomas; Delannoy, Sabine; Fach, Patrick; Beutin, Lothar; Sergentet-Thévenot, Delphine; Cournoyer, Benoit; Loukiadis, Estelle

    2016-10-01

    Tellurite (Tel)-amended selective media and resistance (Tel-R) are widely used for detecting Shiga toxin-producing Escherichia coli (STEC) from foodstuffs. Tel-R of 81 O157 and non-O157 STEC strains isolated from animal, food and human was thus investigated. Variations of STEC tellurite minimal inhibitory concentration (MIC) values have been observed and suggest a multifactorial and variable tellurite resistome between strains. Some clinically-relevant STEC were found highly susceptible and could not be recovered using a tellurite-based detection scheme. The ter operon was highly prevalent among highly Tel-R STEC but was not always detected among intermediately-resistant strains. Many STEC serogroup strains were found to harbor sublines showing a gradient of MIC values. These Tel-R sublines showed statistically significant log negative correlations with increasing tellurite concentration. Whatever the tellurite concentration, the highest number of resistant sublines was observed for STEC belonging to the O26 serogroup. Variations in the number of these Tel-R sublines could explain the poor recovery of some STEC serogroups on tellurite-amended media especially from food products with low levels of contamination. Comparison of tellurite MIC values and distribution of virulence-related genes showed Tel-R and virulence to be related. PMID:27375242

  4. Pathways of Resistance to Thymineless Death in Escherichia coli and the Function of UvrD

    OpenAIRE

    Fonville, Natalie C.; Vaksman, Zalman; DeNapoli, Jessica; Hastings, P. J.; Rosenberg, Susan M.

    2011-01-01

    Thymineless death (TLD) is the rapid loss of viability in bacterial, yeast, and human cells starved of thymine. TLD is the mode of action of common anticancer drugs and some antibiotics. TLD in Escherichia coli is accompanied by blocked replication and chromosomal DNA loss and recent work identified activities of recombination protein RecA and the SOS DNA-damage response as causes of TLD. Here, we examine the basis of hypersensitivity to thymine deprivation (hyper-TLD) in mutants that lack th...

  5. Molecular characterization of vancomycin-resistant enterococci and extended-spectrum beta-lactamase-containing Escherichia coli isolates in wild birds from the Azores Archipelago

    OpenAIRE

    2011-01-01

    Abstract To study the prevalence of vancomycin-resistant enterococci (VRE) and extended-spectrum beta-lactamases (ESBLs) containing Escherichia coli isolates, and the mechanisms of resistance implicated, 220 faecal samples from wild birds were collected between 2006 and 2010 in the Azores Archipelago. Samples were spread in Slanetz-Bartley agar plates supplemented with 4 mg/L of vancomycin and in Levine agar plates supplemented with 2 mg/L of cefotaxime for VRE and ESBL-containing ...

  6. Molecular characterization and drug resistance of Escherichia coli strains isolated from urine from long-term care facility residents in Cracow, Poland

    OpenAIRE

    Pobiega, Monika; Wojkowska-Mach, Jadwiga; Chmielarczyk, Agnieszka; Romaniszyn, Dorota; Adamski, Paweł; Heczko, Piort B.; Gryglewska, Barbara; Grodzicki, Tomasz

    2013-01-01

    Background The aim of this study was to assess the prevalence of multidrug-resistant Escherichia coli and extended-spectrum β-lactamases (ESBL) pathogens isolated from asymptomatic bacteriuria and urinary tract infections (UTIs), and the relationship between the phylogeny, antimicrobial resistance, and virulence among isolates in residents of 3 long-term care facilities (LTCF) in Krakow, Poland. Material/Methods This was point prevalence study and prospective infection control in a group of 2...

  7. Genome Sequence of Avian Escherichia coli Strain IHIT25637, an Extraintestinal Pathogenic E. coli Strain of ST131 Encoding Colistin Resistance Determinant MCR-1.

    Science.gov (United States)

    Ewers, Christa; Göttig, Stephan; Bülte, Maria; Fiedler, Sophie; Tietgen, Manuela; Leidner, Ursula; Heydel, Carsten; Bauerfeind, Rolf; Semmler, Torsten

    2016-01-01

    Sequence type 131 (ST131) is one of the predominant Escherichia coli lineages among extraintestinal pathogenic E. coli (ExPEC) that causes a variety of diseases in humans and animals and frequently shows multidrug resistance. Here, we report the first genome sequence of an ST131-ExPEC strain from poultry carrying the plasmid-encoded colistin resistance gene mcr-1. PMID:27587807

  8. Resistance of uropathogenic strains of Escherichia coli in pregnant women and other women in generative ages in comparison with antibiotics consumption in Zagreb

    OpenAIRE

    Marcel Leppée,; Ana Mlinarić-Džepina,; Josip Čulig; Jasmina Vraneš,

    2010-01-01

    Aim To compare resistance of uropathogenic strains of Escherichia coli (UPEC) to antibiotics in women in generative ages and pregnant women during two year period (2004 and 2008) in Zagreb, andcomparison of resistance and the consumption of antibiotics. Methods The standard disk-diffusion method was used for sensitivity testing to 16 different antibiotics.Data on antibiotic utilization were used to calculate the number of defined daily doses (DDD) and DDD per 1000 inhabitants using Anatomical...

  9. Genome Sequence of Avian Escherichia coli Strain IHIT25637, an Extraintestinal Pathogenic E. coli Strain of ST131 Encoding Colistin Resistance Determinant MCR-1

    Science.gov (United States)

    Göttig, Stephan; Bülte, Maria; Fiedler, Sophie; Tietgen, Manuela; Leidner, Ursula; Heydel, Carsten; Bauerfeind, Rolf; Semmler, Torsten

    2016-01-01

    Sequence type 131 (ST131) is one of the predominant Escherichia coli lineages among extraintestinal pathogenic E. coli (ExPEC) that causes a variety of diseases in humans and animals and frequently shows multidrug resistance. Here, we report the first genome sequence of an ST131-ExPEC strain from poultry carrying the plasmid-encoded colistin resistance gene mcr-1. PMID:27587807

  10. Molecular Characterization of Resistance to Extended-Spectrum Cephalosporins in Clinical Escherichia coli Isolates from Companion Animals in the United States ▿ †

    OpenAIRE

    Shaheen, Bashar W.; Nayak, Rajesh; Foley, Steven L.; Kweon, Ohgew; Deck, Joanna; Park, Miseon; Rafii, Fatemeh; Boothe, Dawn M.

    2011-01-01

    Resistance to extended-spectrum cephalosporins (ESC) among members of the family Enterobacteriaceae occurs worldwide; however, little is known about ESC resistance in Escherichia coli strains from companion animals. Clinical isolates of E. coli were collected from veterinary diagnostic laboratories throughout the United States from 2008 to 2009. E. coli isolates (n = 54) with reduced susceptibility to ceftazidime or cefotaxime (MIC ≥ 16 μg/ml) and extended-spectrum-β-lactamase (ESBL) phenotyp...

  11. Association of Veterinary Third-Generation Cephalosporin Use with the Risk of Emergence of Extended-Spectrum-Cephalosporin Resistance in Escherichia coli from Dairy Cattle in Japan

    OpenAIRE

    Sato, Toyotaka; Okubo, Torahiko; Usui, Masaru; Yokota, Shin-ichi; Izumiyama, Satoshi; Tamura, Yutaka

    2014-01-01

    The use of extended-spectrum cephalosporins in food animals has been suggested to increase the risk of spread of Enterobacteriaceae carrying extended-spectrum β-lactamases to humans. However, evidence that selection of extended-spectrum cephalosporin–resistant bacteria owing to the actual veterinary use of these drugs according to criteria established in cattle has not been demonstrated. In this study, we investigated the natural occurrence of cephalosporin-resistant Escherichia coli in dairy...

  12. Commonality among Fluoroquinolone-Resistant Sequence Type ST131 Extraintestinal Escherichia coli Isolates from Humans and Companion Animals in Australia▿†

    OpenAIRE

    Platell, Joanne L.; Cobbold, Rowland N.; Johnson, James R.; Heisig, Anke; Heisig, Peter; Clabots, Connie; Kuskowski, Michael A.; Trott, Darren J

    2011-01-01

    Escherichia coli sequence type 131 (ST131), an emergent multidrug-resistant extraintestinal pathogen, has spread epidemically among humans and was recently isolated from companion animals. To assess for human-companion animal commonality among ST131 isolates, 214 fluoroquinolone-resistant extraintestinal E. coli isolates (205 from humans, 9 from companion animals) from diagnostic laboratories in Australia, provisionally identified as ST131 by PCR, selectively underwent PCR-based O typing and ...

  13. Prevalence and risk factors for carriage of antimicrobial-resistant Escherichia coli on household and small-scale chicken farms in the Mekong Delta of Vietnam

    OpenAIRE

    Nguyen, V.T.; CARRIQUE-MAS, J. J.; Ngo, T.H; Ho, H M; Ha, T.T.; CAMPBELL, J. I.; Nguyen, T N; Hoang, N.N.; PHAM, V. M.; Wagenaar, J. A.; Hardon, A.; Thai, Q.H.; Schultsz, C

    2015-01-01

    Objectives: To describe the prevalence of antimicrobial resistance among commensal Escherichia coli isolates on household and small-scale chicken farms, common in southern Vietnam, and to investigate the association of antimicrobial resistance with farming practices and antimicrobial usage. Methods: We collected data on farming and antimicrobial usage from 208 chicken farms. E. coli was isolated from boot swab samples using MacConkey agar (MA) and MA with ceftazidime, nalidixic acid or gentam...

  14. Intestinal microbiota shifts towards elevated commensal Escherichia coli loads abrogate colonization resistance against Campylobacter jejuni in mice.

    Directory of Open Access Journals (Sweden)

    Lea-Maxie Haag

    Full Text Available BACKGROUND: The zoonotic pathogen Campylobacter jejuni is a leading cause of bacterial foodborne enterocolitis in humans worldwide. The understanding of immunopathology underlying human campylobacteriosis is hampered by the fact that mice display strong colonization resistance against the pathogen due to their host specific gut microbiota composition. METHODOLOGY/PRINCIPAL FINDINGS: Since the microbiota composition changes significantly during intestinal inflammation we dissected factors contributing to colonization resistance against C. jejuni in murine ileitis, colitis and in infant mice. In contrast to healthy animals C. jejuni could stably colonize mice suffering from intestinal inflammation. Strikingly, in mice with Toxoplasma gondii-induced acute ileitis, C. jejuni disseminated to mesenteric lymphnodes, spleen, liver, kidney, and blood. In infant mice C. jejuni infection induced enterocolitis. Mice suffering from intestinal inflammation and C. jejuni susceptible infant mice displayed characteristical microbiota shifts dominated by increased numbers of commensal Escherichia coli. To further dissect the pivotal role of those distinct microbiota shifts in abrogating colonization resistance, we investigated C. jejuni infection in healthy adult mice in which the microbiota was artificially modified by feeding live commensal E. coli. Strikingly, in animals harboring supra-physiological intestinal E. coli loads, colonization resistance was significantly diminished and C. jejuni infection induced enterocolitis mimicking key features of human campylobacteriosis. CONCLUSION/SIGNIFICANCE: Murine colonization resistance against C. jejuni is abrogated by changes in the microbiota composition towards elevated E. coli loads during intestinal inflammation as well as in infant mice. Intestinal inflammation and microbiota shifts thus represent potential risk factors for C. jejuni infection. Corresponding interplays between C. jejuni and microbiota might

  15. The Widespread Presence of a Multidrug-Resistant Escherichia coli ST131 Clade among Community-Associated and Hospitalized Patients.

    Directory of Open Access Journals (Sweden)

    P Martijn den Reijer

    Full Text Available The extent of entry of multidrug-resistant Escherichia coli from the community into the hospital and subsequent clonal spread amongst patients is unclear. To investigate the extent and direction of clonal spread of these bacteria within a large teaching hospital, we prospectively genotyped multidrug-resistant E. coli obtained from community- and hospital associated patient groups and compared the distribution of diverse genetic markers.A total of 222 E. coli, classified as multi-drug resistant according to national guidelines, were retrieved from both screening (n = 184 and non-screening clinical cultures (n = 38 from outpatients and patients hospitalized for various periods. All isolates were routinely genotyped using an amplified fragment length polymorphism (AFLP assay and real-time PCR for CTX-M genes. Multi-locus sequence typing was additionally performed to confirm clusters. Based on demographics, patients were categorized into two groups: patients that were not hospitalized or less than 72 hours at time of strain isolation (group I and patients that were hospitalized for at least 72 hours (group II.Genotyping showed that most multi-drug resistant E. coli either had unique AFLP profiles or grouped in small clusters of maximally 8 isolates. We identified one large ST131 clade comprising 31% of all isolates, containing several AFLP clusters with similar profiles. Although different AFLP clusters were found in the two patient groups, overall genetic heterogeneity was similar (35% vs 28% of isolates containing unique AFLP profiles, respectively. In addition, similar distributions of CTX-M groups, including CTX-M 15 (40% and 44% of isolates in group I and II, respectively and ST131 (32% and 30% of isolates, respectively were found.We conclude that multi-drug resistant E. coli from the CTX-M 15 associated lineage ST131 are widespread amongst both community- and hospital associated patient groups, with similar genetic diversity and similar

  16. Toxic epidermal necrolysis and agranulocytosis: Rare adverse effects of ciprofloxacin

    OpenAIRE

    Upadya Gatha; Ruxana K

    2009-01-01

    Ciprofloxacin is one of the most commonly used antibacterial agents with relatively few side effects. Serious adverse reactions reported with ciprofloxacin are rare with an incidence of 0.6%. Recently we came across two rare adverse effects of ciprofloxacin, viz. toxic epidermal necrolysis and agranulocytosis. To our knowledge, a total of seven cases have been reported in the literature documenting an association between oral ciprofloxacin administration and toxic epidermal necrolysis....

  17. The prevalence of OqxAB multidrug efflux pump amongst olaquindox resistant Escherichia coli in pigs

    DEFF Research Database (Denmark)

    Hansen, L. H.; Sørensen, S. J.; Jørgensen, H. S.;

    2005-01-01

    The quinoxaline olaquindox has been used extensively as a growth promoter for pigs. Recently, we isolated a plasmid (pOLA52) conferring resistance to olaquindox from swine manure. On this plasmid, the oqxA and oqxB genes encode an RND-family multidrug efflux pump, OqxAB. It facilitates resistance...

  18. Antibiotic resistance pattern in uropathogens

    Directory of Open Access Journals (Sweden)

    Gupta V

    2002-01-01

    Full Text Available Uropathogenic strains from inpatient and outpatient departments were studied from April 1997 to March 1999 for their susceptibility profiles. The various isolates were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Acinetobacter baumanii and Enterococcus faecalis. Antibiotic susceptibility pattern of these isolates revealed that for outpatients, first generation cephalosporins, nitrofurantoin, norfloxacin/ciprofloxacin were effective for treatment of urinary tract infection but for inpatients, parenteral therapy with newer aminoglycosides and third generation cephalosporins need to be advocated as the organisms for nosocomial UTI exhibit a high degree of drug resistance. Trimethoprim and sulphamethoxazole combination was not found to be effective for the treatment of urinary tract infections as all the uropathogens from inpatients and outpatients showed high degree of resistance to co-trimoxazole. Culture and sensitivity of the isolates from urine samples should be done as a routine before advocating the therapy.

  19. Multidrug resistant commensal Escherichia coli in animals and its impact for public health

    Directory of Open Access Journals (Sweden)

    Ama eSzmolka

    2013-09-01

    Full Text Available After the era of plentiful antibiotics we are alarmed by the increasing number of antibiotic resistant strains. The genetic flexibility and adaptability of E. coli to constantly changing environments allows to acquire a great number of antimicrobial resistance mechanisms. Commensal strains of E. coli as versatile residents of the lower intestine are also repeatedly challenged by antimicrobial pressures during the lifetime of their host. As a consequence, commensal strains acquire the respective resistance genes, and/or develop resistant mutants in order to survive and maintain microbial homeostasis in the lower intestinal tract. Thus, commensal E. coli strains are regarded as indicators of antimicrobial load on their hosts. This chapter provides a short historic background of the appearance and presumed origin and transfer of antimicrobial resistance genes in commensal intestinal E. coli of animals with comparative information on their pathogenic counterparts. The dynamics, development and ways of evolution of resistance in the E. coli populations differ according to hosts, resistance mechanisms and antimicrobial classes used. The most frequent tools of E. coli against a variety of antimicrobials are the efflux pumps and mobile resistance mechanisms carried by plasmids and/or other transferable elements. The emergence of hybrid plasmids (both resistance and virulence among E. coli is of further concern. Co-existence and co-transfer of these bad genes in this huge and most versatile in vivo compartment may represent an increased public health risk in the future. Significance of multidrug resistant (MDR commensal E. coli seem to be highest in the food animal industry, acting as reservoir for intra- and interspecific exchange and a source for spread of MDR determinants through contaminated food to humans. Thus, public health potential of MDR commensal E. coli of food animals can be a concern and needs monitoring and more molecular analysis in the

  20. Antimicrobial resistance and spread of multi drug resistant Escherichia coli isolates collected from nine urology services in the Euregion Meuse-Rhine.

    Directory of Open Access Journals (Sweden)

    Christina F M van der Donk

    Full Text Available We determined the prevalence and spread of antibiotic resistance and the characteristics of ESBL producing and/or multi drug resistant (MDR Escherichia coli isolates collected from urine samples from urology services in the Euregio Meuse-Rhine, the border region of the Netherlands (n=176, Belgium (n=126 and Germany (n=119. Significant differences in resistance between the three regions were observed. Amoxicillin-clavulanic acid resistance ranged from 24% in the Netherlands to 39% in Belgium (p=0.018, from 20% to 40% (p<0.004 for the fluoroquinolones and from 20% to 40% (p=0.018 for the folate antagonists. Resistance to nitrofurantoin was less than 5%. The prevalence of ESBL producing isolates varied from 2% among the Dutch isolates to 8% among the German ones (p=0.012 and were mainly CTX-M 15. The prevalence of MDR isolates among the Dutch, German and Belgian isolates was 11%, 17% and 27%, respectively (p< =0.001 for the Belgian compared with the Dutch isolates. The majority of the MDR and ESBL producing isolates belonged to ST131. This study indicates that most antibiotics used as first choice oral empiric treatment for UTIs (amoxicillin-clavulanic acid, fluoroquinolones and folate antagonists are not appropriate for this purpose and that MDR strains such as CTX-M producing ST131 have spread in the entire Euregion. Our data stress the importance of ward specific surveillance to optimize empiric treatment. Also, prudent use of antibiotics and further research to alternative agents are warranted.

  1. Antimicrobial resistance, virulence factors and genetic diversity of Escherichia coli isolates from household water supply in Dhaka, Bangladesh.

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Talukdar

    Full Text Available BACKGROUND: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. METHODOLOGY/PRINCIPAL FINDINGS: A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84 of the isolates were multi-drug(≥ 3 classes of antibiotics resistant (MDR and 26% (n = 22 of these were positive for extended spectrum β-lactamase (ESBL. Of the 22 ESBL-producers, 20 were positive for bla CTX-M-15, 7 for bla OXA-1-group (all had bla OXA-47 and 2 for bla CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16 of the isolates carried virulence gene(s characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8 of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates. SIGNIFICANCE: Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in

  2. The European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2011

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-05-01

    Full Text Available The antimicrobial resistance data among zoonotic and indicator bacteria in 2011, submitted by 26 European Union Member States, were jointly analysed by the European Food Safety Authority and the European Centre for Disease Prevention and Control. Data covered resistance in zoonotic Salmonella and Campylobacter isolates from humans, food and animals, and in indicator Escherichia coli and enterococci isolates from animals and food. Data on methicillin-resistant Staphylococcus aureus in animals and food were also presented. Resistance in isolates from humans were mainly interpreted using clinical breakpoints, while animal and food isolate resistance was interpreted using epidemiological cut-off values. Resistance was commonly found in isolates from humans, animals and food, although disparities in resistance were frequently observed between Member States. High resistance levels were recorded to ampicillin, tetracyclines and sulfonamides in Salmonella isolates from humans, while resistance to third-generation cephalosporins and fluoroquinolones remained low. In Salmonella and indicator Escherichia coli isolates from fowl, pigs, cattle and meat thereof, resistance to ampicillin, tetracyclines and sulfonamides was also commonly detected, while resistance to third-generation cephalosporins was low. Moderate to high resistance to (fluoroquinolones was observed in Salmonella isolates from turkeys, fowl and broiler meat. In Campylobacter isolates from human cases, resistance to ampicillin, ciprofloxacin, nalidixic acid and tetracyclines was high, while resistance to erythromycin was low to moderate. High resistance to ciprofloxacin, nalidixic acid and tetracyclines was observed in Campylobacter isolates from fowl, broiler meat, pigs and cattle, whereas much lower levels were observed for erythromycin and gentamicin. Among the indicator enterococci isolates from animals and food, resistance to tetracyclines and erythromycin was commonly detected. The

  3. Efficacy of ciprofloxacin against Leptospira interrogans serogroup icterohaemorrhagiae.

    OpenAIRE

    Shalit, I; Barnea, A; Shahar, A

    1989-01-01

    Ciprofloxacin activity against Leptospira interrogans serogroup icterohaemorrhagiae was studied in vitro and in an animal model. The MBC of ciprofloxacin was 0.6 microgram/ml. Three of three Syrian hamsters died 8 to 9 days after intraperitoneal challenge with 10(6) leptospires. In contrast, five of six animals given ciprofloxacin 3 or 5 days after challenge survived.

  4. Impact of antibiotic restriction on resistance levels of Escherichia coli: a controlled interrupted time series study of a hospital-wide antibiotic stewardship programme

    DEFF Research Database (Denmark)

    Boel, Jonas Bredtoft; Andreasen, Viggo; Jarløv, Jens Otto;

    2016-01-01

    of E. coli. Results were directly compared with data from the control hospital utilizing a subtracted time series (STS). RESULTS: Direct comparison with the control hospital showed that the ASP was associated with a significant change in the level of use of cephalosporins [-151 DDDs/1000 bed-days (95......% CI -177, -126)] and fluoroquinolones [-44.5 DDDs/1000 bed-days (95% CI -58.9, -30.1)]. Resistance of E. coli showed a significant change in slope for cefuroxime [-0.13 percentage points/month (95% CI -0.21, -0.057)] and ciprofloxacin [-0.15 percentage points/month (95% CI -0.26, -0.038)]. CONCLUSIONS...

  5. Safety and efficacy of levofloxacin versus ciprofloxacin for the treatment of chronic bacterial prostatitis in Chinese patients

    Institute of Scientific and Technical Information of China (English)

    Zhi-Chao Zhang; Feng-Shuo Jin; Dong-Ming Liu; Zhou-Jun Shen; Ying-Hao Sun; Ying-Lu Guo

    2012-01-01

    Levofloxacin is a synthetic fluoroquinolone that is usually used to treat chronic bacterial prostatitis.We investigated the safety and efficacy of levofloxacin compared with ciprofloxacin for the treatment of chronic bacterial prostatitis in Chinese patients.This was a multicenter,open-label,randomized controlled non-inferiority trial.Four hundred and seventy-one patients with clinical symptoms/signs were enrolled into the study,and 408 patients were microbiologically confirmed chronic bacterial prostatitis,who were randomized to either oral levofloxacin (500 mg q.d.) or ciprofloxacin (500 mg b.i.d.) for 4 weeks.Bacterial clearance rate,clinical symptoms/signs,adverse reactions and disease recurrence were assessed.The clinical symptoms and signs (including dysuria,perineal discomfort or pain) and bacteria cultures in 209 patients treated with levofloxacin and 199 patients treated with ciprofloxacin were similar.The most common bacteria were Escherichia coliand Staphylococcus aureus.One to four weeks after the end of 4 weeks treatment,the bacterial clearance rate (86.06% vs.60.03%; P<O.05) and the clinical efficacy (including clinical cure and clinical improvement(93.30% vs.71.86%; P<O.05)) were significantly higher in the levofioxacin-treated group than in the ciprofloxacin-treated group.The microbiological recurrence rate was significantly lower in the levofloxacin-treated group than in the ciprofloxacin-treated group (4.00% vs.19.25%; P<O.05).Rates of adverse events and treatment-related adverse events were slightly lower in the levofloxacin-treated group than in ciprofloxacin-treated group.Levofloxacin showed some advantages over ciprofloxacin in terms of clinical efficacy and disease recurrence,with a low rate of adverse events,for the treatment of chronic bacterial prostatitis in Chinese patients.

  6. Surveillance of Kanamycin Resistance to Escherichia coli from Swine by Digoxigenin-labled Plasmid Probe

    Institute of Scientific and Technical Information of China (English)

    YANG Han-chun; ZHAO Jing; LIU Jin-hua; ZHA Zhen-lin; CHEN Yan-hong

    2002-01-01

    A 4.34kb EcoR I fragment of kanamycin resistance plasmid from pET - 9a was purified by a DNA purification kit. The fragment was labeled with digoxigenin-dUTP with a commercial kit. A dot-blot hybridization and a colony hybridization test with the probe were successfully developed for the surveillance of Kanamycin resistance to E. coli from swine. It was shown that the methods obtained 100% concordance in a positive tate. It was indicated that the method was available for the surveillance of kanamycin resistance to E.coli from swine.

  7. Automated radiosynthesis of [18F]ciprofloxacin

    International Nuclear Information System (INIS)

    We transferred the previously published manual synthesis of [18F]ciprofloxacin (decay-corrected RCY: 5.5±1.0%) to an automated synthesis module (TRACERlabTM FXFDG, GE Healthcare) and observed a strong decrease in RCY (0.4±0.4%). When replacing the standard 15-mL glassy carbon reactor of the synthesis module with a 3-mL V-shaped borosilicate glass reactor a considerable improvement in RCY was observed. [18F]Ciprofloxacin was obtained in a RCY of 2.7±1.4% (n=23) with a specific activity at EOS of 1.4±0.5 GBq/µmol in a synthesis time of 160 min. - Highlights: • Automated synthesis of [18F]ciprofloxacin in a TRACERlabTM FXFDG (GE Healthcare) synthesis module was developed. • Dependence of radiochemical yield on reactor type was observed. • 3-mL V-shaped borosilicate glass reactor gave higher radiochemical yield as compared with standard 15-mL glassy carbon reactor. • V-shaped borosilicate glass reactor might also give higher radiochemical yield for other [18F]radiotracers than [18F]ciprofloxacin

  8. Clinical Efficacy of ciprofloxacin and ofloxacin

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    The cliniueal efficacy, antibacterial activity and adverse effects of ciprofloxacin (CPLX) and ofloxacin (OFLX) produced in our country were compared in five clinical hospitals in Beijing and Guangzhou in 1992. Two groups, each consisting of 100 cases, were treated with. CPLX and OFLX respectively. The total

  9. Phylogenetic and molecular insights into the evolution of multidrug-resistant porcine enterotoxigenic Escherichia coli in Australia.

    Science.gov (United States)

    Abraham, Sam; Trott, Darren J; Jordan, David; Gordon, David M; Groves, Mitchell D; Fairbrother, John M; Smith, Matthew G; Zhang, Ren; Chapman, Toni A

    2014-08-01

    This study investigated the phylogeny and molecular epidemiology of Australian porcine enterotoxigenic Escherichia coli (ETEC) isolates (n=70) by performing multilocus sequence typing (MLST), random amplified polymorphic DNA (RAPD) analysis, virulence gene analysis, plasmid, bacteriocin, integron and antimicrobial resistance gene typing, and antimicrobial susceptibility phenotyping. Isolates of the most commonly observed O serogroup (O149) were highly clonal with a lower frequency of antimicrobial resistance compared with the less common O141 serogroup isolates, which were more genetically diverse and resistant to a greater array of antimicrobials. The O149 and O141 isolates belonged to sequence types (STs) ST100 and ST1260, respectively. A small number of new STs were identified for the least common serogroups, including O157 (ST4245), O138 (ST4244), O139 (ST4246) and O8 (ST4247). A high frequency of plasmid replicons was observed among all ETEC isolates. However, O149 isolates predominantly carried IncFIB, I1, HI1 and FIC, whereas O141 isolates carried a more varied array, including IncI1, FIB, FIC, HI1, I1, Y and, most significantly, A/C. O141 isolates also possessed a greater diversity of bacteriocins, with almost one-half of the isolates carrying colicin E3 (44.4%; 12/27) and E7 (48.1%; 13/27). This study shows that Australian porcine ETEC are distinct from isolates obtained in other parts of the world with respect to the MLST profile and the absence of resistance to critically important antimicrobials, including third-generation cephalosporins and fluoroquinolones.

  10. Incidence and impact on clinical outcome of infections with piperacillin/tazobactam resistant Escherichia coli in ICU: A retrospective study

    Directory of Open Access Journals (Sweden)

    Mounier Roman

    2008-05-01

    Full Text Available Abstract Background Escherichia coli infections are frequent in ICU patients. The increased resistance to fluoroquinolones and amoxicillin/clavulanate of this pathogen mandates the prescription of broad-spectrum antibiotics such as piperacillin/tazobactam (PIP-TAZ or third generation cephalosporins (3GC. Methods To assess incidence and impact on clinical outcome of infections with PIP-TAZ resistant E. coli in ICU patients, we conducted a retrospective cohort study with infections due to PIP-TAZ resistant (PIP-TAZ R or to PIP-TAZ susceptible strains (PIP-TAZ S between 1 January 2002 and 30 June 2004. Results Of 83 strains, 13 were PIP-TAZ R: 2 strains produced an extended-spectrum β-lactamase (2%, 11 produced a high level penicillinase (13%. Prior amoxicillin or amoxicillin/clavulanate prescription was reported in 7 cases (54% of infections with PIP-TAZ R isolates and in 15 cases (21% of infections with PIP-TAZ S isolates (p = 0.03. Time of onset of the infection from hospital admission was longer in case of infections with PIP-TAZ R than with PIP-TAZ S isolates (22 ± 32 vs 10 ± 21 days, p = 0.01. The overall ICU mortality rate was 38%. Mortality and length of stay in ICU were similar in case of infections with PIP-TAZ R isolates and with PIP-TAZ S isolates. Conclusion Infections with PIP-TAZ R E. coli are frequent in ICU patients. No prognostic impact of this pattern of resistance was found. Prescription of PIP-TAZ for empirical treatment of E. coli infections in ICU however exposes to inappropriate therapy.

  11. Adenylate cyclase and the cyclic AMP receptor protein modulate stress resistance and virulence capacity of uropathogenic Escherichia coli.

    Science.gov (United States)

    Donovan, Grant T; Norton, J Paul; Bower, Jean M; Mulvey, Matthew A

    2013-01-01

    In many bacteria, the second messenger cyclic AMP (cAMP) interacts with the transcription factor cAMP receptor protein (CRP), forming active cAMP-CRP complexes that can control a multitude of cellular activities, including expanded carbon source utilization, stress response pathways, and virulence. Here, we assessed the role of cAMP-CRP as a regulator of stress resistance and virulence in uropathogenic Escherichia coli (UPEC), the principal cause of urinary tract infections worldwide. Deletion of genes encoding either CRP or CyaA, the enzyme responsible for cAMP synthesis, attenuates the ability of UPEC to colonize the bladder in a mouse infection model, dependent on intact innate host defenses. UPEC mutants lacking cAMP-CRP grow normally in the presence of glucose but are unable to utilize alternate carbon sources like amino acids, the primary nutrients available to UPEC within the urinary tract. Relative to the wild-type UPEC isolate, the cyaA and crp deletion mutants are sensitive to nitrosative stress and the superoxide generator methyl viologen but remarkably resistant to hydrogen peroxide (H(2)O(2)) and acid stress. In the mutant strains, H(2)O(2) resistance correlates with elevated catalase activity attributable in part to enhanced translation of the alternate sigma factor RpoS. Acid resistance was promoted by both RpoS-independent and RpoS-dependent mechanisms, including expression of the RpoS-regulated DNA-binding ferritin-like protein Dps. We conclude that balanced input from many cAMP-CRP-responsive elements, including RpoS, is critical to the ability of UPEC to handle the nutrient limitations and severe environmental stresses present within the mammalian urinary tract.

  12. Antimicrobial Resistance and Molecular Epidemiology of Escherichia coli Causing Bloodstream Infections in Three Hospitals in Shanghai, China.

    Directory of Open Access Journals (Sweden)

    Su Wang

    Full Text Available Escherichia coli (E. coli is one of the most frequent and lethal causes of bloodstream infections (BSIs. We carried out a retrospective multicenter study on antimicrobial resistance and phylogenetic background of clinical E. coli isolates recovered from bloodstream in three hospitals in Shanghai. E. coli isolates causing BSIs were consecutively collected between Sept 2013 and Sept 2014. Ninety isolates randomly selected (30 from each hospital were enrolled in the study. Antimicrobial susceptibility testing was performed by disk diffusion. PCR was used to detect antimicrobial resistance genes coding for β-lactamases (TEM, CTX-M, OXA, etc., carbapenemases (IMP, VIM, KPC, NDM-1 and OXA-48, and phylogenetic groups. eBURST was applied for analysis of multi-locus sequence typing (MLST. The resistance rates for penicillins, second-generation cephalosporins, fluoroquinolone and tetracyclines were high (>60%. Sixty-one of the 90 (67.8% strains enrolled produced ESBLs and no carbapenemases were found. Molecular analysis showed that CTX-M-15 (25/61, CTX-M-14 (18/61 and CTX-M-55 (9/61 were the most common ESBLs. Phylogenetic group B2 predominated (43.3% and exhibited the highest rates of ESBLs production. ST131 (20/90 was the most common sequence type and almost assigned to phylogenetic group B2 (19/20. The following sequence types were ST405 (8/90 and ST69 (5/90. Among 61 ESBL-producers isolates, B2 (26, 42.6% and ST131 (18, 29.5% were also the most common phylogenetic group and sequence type. Genetic diversity showed no evidence suggesting a spread of these antimicrobial resistant isolates in the three hospitals. In order to provide more comprehensive and reliable epidemiological information for preventing further dissemination, well-designed and continuous surveillance with more hospitals participating was important.

  13. Antimicrobial Resistance and Molecular Epidemiology of Escherichia coli Causing Bloodstream Infections in Three Hospitals in Shanghai, China.

    Science.gov (United States)

    Wang, Su; Zhao, Sheng-Yuan; Xiao, Shu-Zhen; Gu, Fei-Fei; Liu, Qing-Zhong; Tang, Jin; Guo, Xiao-Kui; Ni, Yu-Xing; Han, Li-Zhong

    2016-01-01

    Escherichia coli (E. coli) is one of the most frequent and lethal causes of bloodstream infections (BSIs). We carried out a retrospective multicenter study on antimicrobial resistance and phylogenetic background of clinical E. coli isolates recovered from bloodstream in three hospitals in Shanghai. E. coli isolates causing BSIs were consecutively collected between Sept 2013 and Sept 2014. Ninety isolates randomly selected (30 from each hospital) were enrolled in the study. Antimicrobial susceptibility testing was performed by disk diffusion. PCR was used to detect antimicrobial resistance genes coding for β-lactamases (TEM, CTX-M, OXA, etc.), carbapenemases (IMP, VIM, KPC, NDM-1 and OXA-48), and phylogenetic groups. eBURST was applied for analysis of multi-locus sequence typing (MLST). The resistance rates for penicillins, second-generation cephalosporins, fluoroquinolone and tetracyclines were high (>60%). Sixty-one of the 90 (67.8%) strains enrolled produced ESBLs and no carbapenemases were found. Molecular analysis showed that CTX-M-15 (25/61), CTX-M-14 (18/61) and CTX-M-55 (9/61) were the most common ESBLs. Phylogenetic group B2 predominated (43.3%) and exhibited the highest rates of ESBLs production. ST131 (20/90) was the most common sequence type and almost assigned to phylogenetic group B2 (19/20). The following sequence types were ST405 (8/90) and ST69 (5/90). Among 61 ESBL-producers isolates, B2 (26, 42.6%) and ST131 (18, 29.5%) were also the most common phylogenetic group and sequence type. Genetic diversity showed no evidence suggesting a spread of these antimicrobial resistant isolates in the three hospitals. In order to provide more comprehensive and reliable epidemiological information for preventing further dissemination, well-designed and continuous surveillance with more hospitals participating was important.

  14. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    OpenAIRE

    Liu, Ping; Soupir, Michelle L; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance ...

  15. Multidrug Resistant CTX-M-Producing Escherichia coli: A Growing Threat among HIV Patients in India

    OpenAIRE

    Kesavaram Padmavathy; Krishnan Padma; Sikhamani Rajasekaran

    2016-01-01

    Extended Spectrum β-Lactamases (ESBLs) confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinary E. coli isolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76 E. coli strains isolated from HIV patients fro...

  16. Characterization of Fosfomycin Resistant Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Human and Pig in Taiwan.

    Directory of Open Access Journals (Sweden)

    Sung-Pin Tseng

    Full Text Available To investigate the efficacy of fosfomycin against extended-spectrum β-lactamases (ESBL producing Escherichia coli in Taiwan and the resistance mechanisms and characterization of human and pig isolates, we analyzed 145 ESBL-producing isolates collected from two hospitals (n = 123 and five farms (n = 22 in Taiwan from February to May, 2013. Antimicrobial susceptibilities were determined. Clonal relatedness was determined by PFGE and multi-locus sequence typing. ESBLs, ampC, and fosfomycin resistant genes were detected by PCR, and their flanking regions were determined by PCR mapping and sequencing. The fosfomycin resistant mechanisms, including modification of the antibiotic target (MurA, functionless transporters (GlpT and UhpT and their regulating genes such as uhpA, cyaA, and ptsI, and antibiotic inactivation by enzymes (FosA and FosC, were examined. The size and replicon type of plasmids carrying fosfomycin resistant genes were analyzed. Our results revealed the susceptibility rates of fosfomycin were 94% for human ESBL-producing E. coli isolates and 77% for pig isolates. The PFGE analysis revealed 79 pulsotypes. No pulsotype was found existing in both human and pig isolates. Three pulsotypes were distributed among isolates from two hospitals. ISEcp1 carrying blaCTX-M-group 9 was the predominant transposable elements of the ESBL genes. Among the thirteen fosfomycin resistant isolates, functionless transporters were identified in 9 isolates. Three isolates contained novel amino acid substitutions (Asn67Ile, Phe151Ser and Trp164Ser, Val146Ala and His159Tyr, respectively in MurA (the target of fosfomycin. Four isolates had fosfomycin modified enzyme (fosA3 in their plasmids. The fosA3 gene was harboured in an IncN-type plasmid (101 kbp in the three pig isolates and an IncB/O-type plasmid (113 kbp in the human isolate. In conclusion, we identified that 6% and 23% of the ESBL-producing E. coli from human and pigs were resistant to fosfomycin

  17. Dissemination of cephalosporin resistance genes between Escherichia coli strains from farm animals and humans by specific plasmid lineages.

    Directory of Open Access Journals (Sweden)

    Mark de Been

    2014-12-01

    Full Text Available Third-generation cephalosporins are a class of β-lactam antibiotics that are often used for the treatment of human infections caused by Gram-negative bacteria, especially Escherichia coli. Worryingly, the incidence of human infections caused by third-generation cephalosporin-resistant E. coli is increasing worldwide. Recent studies have suggested that these E. coli strains, and their antibiotic resistance genes, can spread from food-producing animals, via the food-chain, to humans. However, these studies used traditional typing methods, which may not have provided sufficient resolution to reliably assess the relatedness of these strains. We therefore used whole-genome sequencing (WGS to study the relatedness of cephalosporin-resistant E. coli from humans, chicken meat, poultry and pigs. One strain collection included pairs of human and poultry-associated strains that had previously been considered to be identical based on Multi-Locus Sequence Typing, plasmid typing and antibiotic resistance gene sequencing. The second collection included isolates from farmers and their pigs. WGS analysis revealed considerable heterogeneity between human and poultry-associated isolates. The most closely related pairs of strains from both sources carried 1263 Single-Nucleotide Polymorphisms (SNPs per Mbp core genome. In contrast, epidemiologically linked strains from humans and pigs differed by only 1.8 SNPs per Mbp core genome. WGS-based plasmid reconstructions revealed three distinct plasmid lineages (IncI1- and IncK-type that carried cephalosporin resistance genes of the Extended-Spectrum Beta-Lactamase (ESBL- and AmpC-types. The plasmid backbones within each lineage were virtually identical and were shared by genetically unrelated human and animal isolates. Plasmid reconstructions from short-read sequencing data were validated by long-read DNA sequencing for two strains. Our findings failed to demonstrate evidence for recent clonal transmission of

  18. Toward repurposing ciclopirox as an antibiotic against drug-resistant Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae.

    Directory of Open Access Journals (Sweden)

    Kimberly M Carlson-Banning

    Full Text Available Antibiotic-resistant infections caused by gram-negative bacteria are a major healthcare concern. Repurposing drugs circumvents the time and money limitations associated with developing new antimicrobial agents needed to combat these antibiotic-resistant infections. Here we identified the off-patent antifungal agent, ciclopirox, as a candidate to repurpose for antibiotic use. To test the efficacy of ciclopirox against antibiotic-resistant pathogens, we used a curated collection of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae clinical isolates that are representative of known antibiotic resistance phenotypes. We found that ciclopirox, at 5-15 µg/ml concentrations, inhibited bacterial growth regardless of the antibiotic resistance status. At these same concentrations, ciclopirox reduced growth of Pseudomonas aeruginosa clinical isolates, but some of these pathogens required higher ciclopirox concentrations to completely block growth. To determine how ciclopirox inhibits bacterial growth, we performed an overexpression screen in E. coli. This screen revealed that galE, which encodes UDP-glucose 4-epimerase, rescued bacterial growth at otherwise restrictive ciclopirox concentrations. We found that ciclopirox does not inhibit epimerization of UDP-galactose by purified E. coli GalE; however, ΔgalU, ΔgalE, ΔrfaI, or ΔrfaB mutant strains all have lower ciclopirox minimum inhibitory concentrations than the parent strain. The galU, galE, rfaI, and rfaB genes all encode enzymes that use UDP-galactose or UDP-glucose for galactose metabolism and lipopolysaccharide (LPS biosynthesis. Indeed, we found that ciclopirox altered LPS composition of an E. coli clinical isolate. Taken together, our data demonstrate that ciclopirox affects galactose metabolism and LPS biosynthesis, two pathways important for bacterial growth and virulence. The lack of any reported fungal resistance to ciclopirox in over twenty years of use in the clinic

  19. Short communication: heat resistance of Escherichia coli strains in raw milk at different subpasteurization conditions.

    Science.gov (United States)

    Peng, S; Hummerjohann, J; Stephan, R; Hammer, P

    2013-06-01

    A commonly applied treatment of raw milk to reduce bacterial loads is the short-time application of heat at subpasteurization levels under continuous flow, generally referred to as thermization, because this method retains some of the beneficial properties of raw milk. In a previous study, Escherichia coli strains exhibiting increased thermotolerance were found, demanding investigations into their ability to survive thermization. Nine E. coli strains, including 4 Shiga toxin-producing E. coli (STEC) strains, were investigated for their reduction during a thermization treatment in raw milk using a pilot-plant pasteurizer to reflect typically applied commercial conditions. Six of the 9 E. coli strains, including the 4 STEC strains, were similarly inactivated at 60, 62.5, and 65°C, whereas increased thermotolerance was observed for 3 E. coli strains. All strains were reduced to thermization treatment.

  20. Removal of ciprofloxacin from water by birnessite

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Wei-Teh, E-mail: atwtj@mail.ncku.edu.tw [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Chang, Po-Hsiang; Wang, Ya-Siang; Tsai, Yolin; Jean, Jiin-Shuh [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Li, Zhaohui, E-mail: li@uwp.edu [Department of Earth Sciences, National Cheng Kung University, Tainan 70101, Taiwan (China); Department of Geosciences, University of Wisconsin – Parkside, Kenosha, WI 53144 (United States); Krukowski, Keith [Department of Geosciences, University of Wisconsin – Parkside, Kenosha, WI 53144 (United States)

    2013-04-15

    Highlights: ► Ciprofloxacin removal by birnessite was accompanied by interlayer cation exchange. ► Layer expansion and FTIR data suggested ciprofloxacin intercalation into birnessite. ► Adsorption capacity of ciprofloxacin into birnessite was limited by surface area. ► Birnessite in soil systems may provide host for ciprofloxacin accumulation. -- Abstract: With more pharmaceuticals and personal care products detected in the surface and waste waters, studies on interactions between these contaminants and soils or sediments have attracted great attention. In this study, the removal of ciprofloxacin (CIP), a fluoroquinolone antibiotic, by birnessite, a layered manganese oxide, in aqueous solution was investigated by batch studies supplemented by X-ray diffraction (XRD) and Fourier transform infrared analyses. Stoichiometric release of exchangeable cations accompanying CIP removal from water confirmed cation exchange as the major mechanism for CIP uptake by birnessite. Interlayer expansion after CIP adsorption on birnessite as revealed by XRD analyses indicated that intercalation contributed significantly to CIP uptake in addition to external surface adsorption. Correlation of CIP adsorption to specific surface area and cation exchange capacity suggested that the former was the limiting factor for CIP uptake. At the adsorption maximum, CIP molecules formed a monolayer on the birnessite surfaces. The adsorbed CIP could be partially removed using a cationic surfactant at a low initial concentration and mostly removed by AlCl{sub 3} at a higher initial concentration, which further supported the cation exchange mechanism for CIP removal by birnessite. The results indicated that the presence of layered Mn-oxide in the soil and waste water treatment systems may provide host for CIP accumulation.