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Sample records for beta-lactam antibiotic sensitization

  1. Collateral sensitivity between aminoglycosides and beta-lactam antibiotics depends on active proton pumps.

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    Azimi, Leila; Rastegar Lari, Abdolaziz

    2017-11-01

    Selection inversion is the hypothesis for antibiotic resistant inhabitation in bacteria and collateral sensitivity is one of the proposed phenomena for achievement of this hypothesis. The presence of collateral sensitivity associated with the proton motivation pump between the aminoglycosides and beta-lactam group of antibiotics is one of the examples of collateral sensitivity in some studies. The aim of this study was to demonstrate that collateral sensitivity between aminoglycosides and beta-lactam antibiotics associated with proton motivation pump may not be true in all cases. In this study, 100 Pseudomonas aeruginosa were surveyed. Gentamicin and imipenem-resistant strains were confirmed by disc diffusion method and MIC. Active proton motivation pumps were screened by pumps inhibitor. Semi-quantitative Real-Time PCR assay was used to confirm gene overexpression. Seventy-six and 79 out of 100 strains were resistant to gentamicin and imipenem, respectively. Seventy-five strains were resistant to both gentamicin and imipenem. The results of proton pump inhibitor test showed the involvement of active proton motivation pump in 22 of 75 imipenem- and gentamicin-resistant strains. According to Real - Time PCR assay, mexX efflux gene was overexpressed in the majority of isolates tested. The collateral sensitivity effect cannot explain the involvement of active proton motivation pumps in both imipenem and gentamicin-resistant strains simultaneously. Active and/or inactive proton pump in gentamicin-sensitive and/or resistant strains cannot be a suitable example for explanation of collateral sensitivity between aminoglycosides and beta-lactam antibiotics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Evaluation of sensitivity of modified star protocol microbiological method for beta-lactame antibiotics detection in raw cow milk

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    Borović Branka

    2013-01-01

    Full Text Available Antibiotic residues when present in animal tissues, through food chain, can enter human body, causing allergic reactions or facilitating the development of resistant bacterial strains. In order to determine the presence of antibiotics in animal tissues, it is appropriate to use convenient, reliable and sensitive methods. Microbiological methods applied for the detection of antibiotic residues in primary products of animal origin are based on the sensitivity of specific bacterial strains to a particular group of antibiotics. Regulatives on the amount of pesticides, metals and metalloids and other toxic substances, chemotherapeutics, anabolics and other substances which can be found in food ("Off. Gazette", No. 5/92, 11/92 - corr. and 32/02, state that milk and milk products can be used in commercial purposes only if not contain antibiotics in quantities that can be detected by reference methods. The applied method is modified STAR (Screening test for detection of antibiotics protocol, regulated by the CRL (Community Reference Laboratory Fougeres, France, in which the initial validation of the method had been carried out. In accordance with the demands of Regulative Commission EC No657/2002, the sensitivity of modified STAR protocol for beta lactam antibiotics group was examined , that is, there was carried out a contracted validation of the method, which initial validation had been performed at CRL. In a couple of series of experiments, 20 blank samples of raw cow milk originating from animals not treated by antibiotics, had been examined. By the beginning of the experiment samples were stored in a freezer at -20ºC. Samples of raw cow milk enriched by working solutions of seven beta-lactam antibiotics, in order to obtain concentrations at the level of 0.5, 1 and 1.5 MRL (Maximmum Residue Limit for each given antibiotic (Commission Regulation EC No. 37/2010. For detection of beta-lactam antibiotics, there was used Kundrat agar test with

  3. Sensitivity and specificity of various beta-lactam antibiotics and phenotypical methods for detection of TEM, SHV and CTX-M extended-spectrum beta-lactamases.

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    Bedenic, B; Vranes, J; Mihaljevic, Lj; Tonkic, M; Sviben, M; Plecko, V; Kalenic, S

    2007-04-01

    The aim of this study was to compare the sensitivity and specificity of six different beta-lactam antibiotics using five phenotypical tests for detection of extended spectrum beta-lactamases (ESBLs) based on synergism of beta-lactam antibiotics and clavulanate. Experiments were performed on a set of 80 Klebsiella pneumoniae strains and 105 Escherichia coli strains with previously characterized ESBLs (SHV, TEM and CTX-M). ESBLs were detected by five different phenotypical methods: MIC (minimum inhibitory concentration) determination of beta-lactam antibiotics with and without clavulanate, double-disk synergy test (DDST), inhibitor-potentiated disk-diffusion test (IPDDT), CLSI-Clinical and Laboratory Standard Institution (former NCCLS) combined-disk-test, and modified MAST-disk-diffusion test (MAST-DD-test). Seven antibiotics were tested as indicators of ESBL production: ceftazidime, cefotaxime, ceftriaxone, aztreonam, ceftibuten, cefpodoxime and cefepime. Ceftazidime and aztreonam were the best indicators for SHV-5, SHV-12 and TEM beta-lactamases whereas cefotaxime and ceftriaxone were the most sensitive in detection of SHV-2 and CTX-M beta-lactamases in DDST, IPDDT and CLSI test. MIC determination of beta-lactam antibiotics with and without clavulanate was the most sensitive method. DDST was the least sensitive test. Double-disk synergy test, which is the most frequently used test for detection of ESBLs in routine laboratories, was the least sensitive independently of the indicator antibiotic. Since MIC determination is a very laborious and time consuming method, we would recommend the NCCLS combined disk test or IPDD test for detection of ESBLs in routine laboratories with 5 mm zone augmentation breakpoint.

  4. Trans-Cinnamaldehyde and Eugenol Increase Acinetobacter baumannii Sensitivity to Beta-Lactam Antibiotics

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    Deepti P. Karumathil

    2018-05-01

    Full Text Available Multi-drug resistant (MDR Acinetobacter baumannii is a major nosocomial pathogen causing a wide range of clinical conditions with significant mortality rates. A. baumannii strains are equipped with a multitude of antibiotic resistance mechanisms, rendering them resistant to most of the currently available antibiotics. Thus, there is a critical need to explore novel strategies for controlling antibiotic resistance in A. baumannii. This study investigated the efficacy of two food-grade, plant-derived antimicrobials (PDAs, namely trans-cinnamaldehyde (TC and eugenol (EG in decreasing A. baumannii’s resistance to seven β-lactam antibiotics, including ampicillin, methicillin, meropenem, penicillin, aztreonam, amoxicillin, and piperacillin. Two MDR A. baumannii isolates (ATCC 17978 and AB 251847 were separately cultured in tryptic soy broth (∼6 log CFU/ml containing the minimum inhibitory concentration (MIC of TC or EG with or without the MIC of each antibiotic at 37°C for 18 h. A. baumannii strains not exposed to the PDAs or antibiotics served as controls. Following incubation, A. baumannii counts were determined by broth dilution assay. In addition, the effect of PDAs on the permeability of outer membrane and efflux pumps in A. baumannii was measured. Further, the effect of TC and EG on the expression of A. baumannii genes encoding resistance to β-lactam antibiotics (blaP, efflux pumps (adeABC, and multi-drug resistant protein (mdrp was studied using real-time quantitative PCR (RT-qPCR. The experiment was replicated three times with duplicate samples of each treatment and control. The results from broth dilution assay indicated that both TC and EG in combination with antibiotics increased the sensitivity of A. baumannii to all the tested antibiotics (P < 0.05. The two PDAs inhibited the function of A. baumannii efflux pump, (AdeABC, but did not increase the permeability of its outer membrane. Moreover, RT-qPCR data revealed that TC and EG

  5. Trans-Cinnamaldehyde and Eugenol Increase Acinetobacter baumannii Sensitivity to Beta-Lactam Antibiotics.

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    Karumathil, Deepti P; Nair, Meera Surendran; Gaffney, James; Kollanoor-Johny, Anup; Venkitanarayanan, Kumar

    2018-01-01

    Multi-drug resistant (MDR) Acinetobacter baumannii is a major nosocomial pathogen causing a wide range of clinical conditions with significant mortality rates. A. baumannii strains are equipped with a multitude of antibiotic resistance mechanisms, rendering them resistant to most of the currently available antibiotics. Thus, there is a critical need to explore novel strategies for controlling antibiotic resistance in A. baumannii . This study investigated the efficacy of two food-grade, plant-derived antimicrobials (PDAs), namely trans -cinnamaldehyde (TC) and eugenol (EG) in decreasing A. baumannii 's resistance to seven β-lactam antibiotics, including ampicillin, methicillin, meropenem, penicillin, aztreonam, amoxicillin, and piperacillin. Two MDR A. baumannii isolates (ATCC 17978 and AB 251847) were separately cultured in tryptic soy broth (∼6 log CFU/ml) containing the minimum inhibitory concentration (MIC) of TC or EG with or without the MIC of each antibiotic at 37°C for 18 h. A. baumannii strains not exposed to the PDAs or antibiotics served as controls. Following incubation, A. baumannii counts were determined by broth dilution assay. In addition, the effect of PDAs on the permeability of outer membrane and efflux pumps in A. baumannii was measured. Further, the effect of TC and EG on the expression of A. baumannii genes encoding resistance to β-lactam antibiotics ( blaP ), efflux pumps ( adeABC ), and multi-drug resistant protein ( mdrp ) was studied using real-time quantitative PCR (RT-qPCR). The experiment was replicated three times with duplicate samples of each treatment and control. The results from broth dilution assay indicated that both TC and EG in combination with antibiotics increased the sensitivity of A. baumannii to all the tested antibiotics ( P increase the permeability of its outer membrane. Moreover, RT-qPCR data revealed that TC and EG down-regulated the expression of majority of the genes associated with β-lactam antibiotic

  6. Beta-Lactam Antibiotic Sensitization and Its Relationship to Allergic Diseases in Tertiary Hospital Nurses

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    Han, Eui-Ryoung; Lim, Seong-Wook; Lim, Seong-Ryoon; Kim, Ji-Na; Park, Sin-Young; Chae, Su-Kyoung; Lim, Hye-Hyeun; Seol, Young-Ae; Bae, You-In; Won, Young-Ho

    2010-01-01

    Purpose Skin allergies through type 1 and 4 hypersensitivity reactions are the most frequent manifestations of drug allergies. We had previously experienced a case of a nurse with cefotiam-induced contact urticaria syndrome. To aid in preventing the progression of drug-induced allergic disease in nurses, we conducted a survey of tertiary hospital nurses who were likely to have been exposed professionally to antibiotics. Methods All 539 staff nurses at a tertiary hospital were asked to respond to a questionnaire regarding antibiotic exposure. Of the 457 nurses (84.8%) who responded, 427 (79.2%) received a physical examination of the hands and 318 (59.0%) received skin prick tests with the β-lactam antibiotics cefotiam, cefoperazone, ceftizoxime, flomoxef, piperacillin and penicillin G. Results A positive response to at least one of the antibiotics occurred in 8 (2.6%) of the 311 subjects included in the analysis and stages 1 and 2 contact urticaria syndrome were observed in 38 (8.9%) and 3 (0.7%) of 427 nurses, respectively. The frequencies of a positive antibiotic skin test (6.9 versus 1.3%, χ2=7.15, P=0.018), stage 1 contact urticaria syndrome (14.4 versus 7.4%, χ2=4.33, P=0.038) and drug allergy (15.3 versus 3.6%, χ2=18.28, P=0.000) were higher in subjects with a positive skin allergy history than in those without. Allergic rhinitis (P=0.02, OR=3.86, CI=1.23-12.06), night cough (P=0.04, OR=3.12, CI=1.03-9.41) and food allergy (P=0.00, OR=9.90, CI=3.38-29.98) were significant risk factors for drug allergy. Conclusions Antibiotic sensitization and drug allergy occurred more frequently in nurses with a positive skin allergy history. Atopy may be an important risk factor for drug allergy. PMID:20358025

  7. Immunological aspects of nonimmediate reactions to beta-lactam antibiotics.

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    Rodilla, Esther Morena; González, Ignacio Dávila; Yges, Elena Laffond; Bellido, Francisco Javier Múñoz; Bara, María Teresa Gracia; Toledano, Félix Lorente

    2010-09-01

    beta-lactam antibiotics are the agents most frequently implied in immune drug adverse reactions. These can be classified as immediate or nonimmediate according to the time interval between the last drug administration and their onset. Mechanisms of immediate IgE-mediated reactions are widely studied and are therefore better understood. Nonimmediate reactions include a broad number of clinical entities like mild maculopapular exanthemas, the most common, and other less frequent but more severe reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, acute exanthematic pustulosis or cytopenias. These nonimmediate reactions are mainly mediated by T cells but the precise underlying mechanisms are not well elucidated. This fact complicates the allergological evaluation of patients with this type of reaction and available tests have demonstrated poor sensitivity and specificity.

  8. Beta lactam antibiotics residues in cow's milk: comparison of efficacy of three screening tests used in Bosnia and Herzegovina.

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    Fejzic, Nihad; Begagic, Muris; Šerić-Haračić, Sabina; Smajlovic, Muhamed

    2014-08-27

    Beta lactam antibiotics are widely used in therapy of cattle, particularly for the treatment of mastitis.  Over 95% of residue testing in dairies in Bosnia and Herzegovina is for Beta lactams. The aim of this paper is to compare the efficacy of three most common screening tests for Beta lactam residues in cow's milk in our country. The tests used in the study are SNAP β Lactam test (Idexx), Rosa Charm β Lactam test and Inhibition MRL test. Study samples included: standardized concentrations of penicillin solution (0, 2, 3, 4, 5 and 6 ppb). In addition we tested milk samples from three equal size study groups (not receiving any antibiotic therapy, treated with Beta lactams for mastitis and treated with Beta lactams for diseases other than mastitis). Sensitivity and specificity were determined for each test, using standard penicillin concentrations with threshold value set at concentration of 4 ppb (Maximum residue level - MLR). Additionally we determined proportions of presumably false negative and false positive results for each test using results of filed samples testing. Agreement of test results for each test pair was assessed through Kappa coefficients interpreted by Landis-Koch scale. Detection level of all tests was shown to be well below MRL. This alongside with effects of natural inhibitors in milk contributed to finding of positive results in untreated and treated animals after the withholding period. Screening tests for beta lactam residues are important tools for ensuring that milk for human consumption is free from antibiotics residues.

  9. [The outpatient use of beta lactam antibiotics in Montenegro before the introduction of new reform strategy on drug market].

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    Duborija-Kovacević, Natasa

    2006-01-01

    The study represents the first investigation of outpatient use of beta lactam antibiotics in Montenegro carried out in accordance with internationally approved methodology (DDD/ATC). The objective of our study was to establish both the scope and overall use of beta lactam antibiotics, and to assess their compatibility with current pharmacotherapeutic guidelines and their use in developed countries. The retrospective pharmaco-epidemiological study comprised a 100%-sample of beta lactams that were used in the period prior to introduction of new reform strategy on drug market. Beta lactam antibiotics (J01C, J01D) were the most frequently applied anti-infectives for systemic use (ATC group J) in 2000 (11.3 DDD/1000 inh./day, 61%). Penicillins (J01C) were the most utilized (8.0 DDD/1000 inh./day, 71%). Cephalosporin derivatives (cephalexin and cefaclor) accounted for the remaining 29% (3.3 DDD/1000 inh./day). Aminopenicillins were prevailing among penicillins (85%). Beta lactamase sensitive penicillins were in the second place and approximately accounted for 14%. The results of our study showed that the use of beta lactam antibacterials could be estimated as partially satisfactory. There is a need to make additional efforts with a view of further rationalization.

  10. Case Study of Intrapartum Antibiotic Prophylaxis and Subsequent Postpartum Beta-Lactam Anaphylaxis.

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    Stark, Mary Ann; Ross, Mary Frances; Kershner, Wendy; Searing, Kimberly

    2015-01-01

    Universal screening for maternal group B Streptococcus (GBS) in the prenatal period has led to administration of intrapartum antibiotic prophylaxis (IAP). Although IAP decreased the rate of early neonatal GBS disease, exposure of childbearing women to penicillin and other beta-lactam antibiotics has increased. Beta-lactam-induced anaphylaxis in the breastfeeding woman during the postpartum period illustrates risk factors for beta-lactam allergy and anaphylaxis. Treatment and nursing implications for this adverse reaction are suggested. © 2015 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  11. Beta lactam antibiotics residues in cow's milk: comparison of efficacy of three screening tests used in Bosnia and Herzegovina

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    Nihad Fejzic

    2014-08-01

    Full Text Available Beta lactam antibiotics are widely used in therapy of cattle, particularly for the treatment of mastitis.  Over 95% of residue testing in dairies in Bosnia and Herzegovina is for Beta lactams. The aim of this paper is to compare the efficacy of three most common screening tests for Beta lactam residues in cow’s milk in our country. The tests used in the study are SNAP β Lactam test (Idexx, Rosa Charm β Lactam test and Inhibition MRL test. Study samples included: standardized concentrations of penicillin solution (0, 2, 3, 4, 5 and 6 ppb. In addition we tested milk samples from three equal size study groups (not receiving any antibiotic therapy, treated with Beta lactams for mastitis and treated with Beta lactams for diseases other than mastitis. Sensitivity and specificity were determined for each test, using standard penicillin concentrations with threshold value set at concentration of 4 ppb (Maximum residue level – MLR. Additionally we determined proportions of presumably false negative and false positive results for each test using results of filed samples testing. Agreement of test results for each test pair was assessed through Kappa coefficients interpreted by Landis-Koch scale. Detection level of all tests was shown to be well below MRL. This alongside with effects of natural inhibitors in milk contributed to finding of positive results in untreated and treated animals after the withholding period. Screening tests for beta lactam residues are important tools for ensuring that milk for human consumption is free from antibiotics residues.

  12. Beta-lactam antibiotics during pregnancy: a cross-sectional comparative study Zagreb-Novi Sad.

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    Erić, M; Leppée, M; Sabo, A; Culig, J

    2012-01-01

    During pregnancy, a number of changes occur in women's body, and some medications are safe and some are not. The aim of our study was to establish the possible correlation between use of beta-lactam antibiotics in pregnancy and occurrence of congenital malformations. The study included 893 pregnant women from Zagreb and 6099 pregnant women from Novi Sad. 527 pregnant women used beta-lactams. First part of the study (one month study) was performed at four maternity hospitals in Zagreb, Croatia. Second part were collected as a part of the study analysing the teratogenicity of drugs used in pregnancy, a longitudinal study performed in Novi Sad district. Pregnant women most frequently used antibacterial agents in the first trimester of pregnancy. They used 15 different antibacterial medications, most often beta-lactams. In Zagreb arm, out of the total number of pregnant women that used medications during pregnancy (859), 231 (26.9%) used beta-lactam antibiotics. Malformations were detected in 8 (3.5%) cases. The prevalence of malformations in newborns whose mothers did not take beta-lactam antibiotics in pregnancy (662) was 2.7% (18 newborns with malformations). In Novi Sad arm, out of the total number of pregnant women that used medications during pregnancy (2013), 296 (14.7%) used beta-lactam antibiotics. Malformations were detected in 14 (4.7%) cases. The prevalence of malformations in newborns whose mothers did not take beta-lactam antibiotics in pregnancy (5803) was 1.7% (99 newborns with malformations). The results show possible teratogenic potential even with those antibacterials which are considered safe (amoxicillin) but as those are usually minor malformations they often pass undetected. International pharmacoepidemiological studies of drug use in pregnancy could substantially contribute to the improvement of pharmacotherapy, and could be of great help in assessing the fetal risks.

  13. Properties of immobilised penicillin G Acylase in beta-lactam antibiotic synthesis

    NARCIS (Netherlands)

    Janssen, M.H.A.

    2006-01-01

    The beta-lactam antibiotics are the most important class of antibiotics used today. In the last decade the production routes of these antibiotics have shifted from chemical routes to more environmentally benign routes using the enzyme penicillin G acylase. For both practical and economical reasons

  14. Continuous infusion vs. bolus dosing: implications for beta-lactam antibiotics.

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    Mohd Hafiz, Abdul-Aziz; Staatz, C E; Kirkpatrick, C M J; Lipman, J; Roberts, J A

    2012-01-01

    Beta-lactam antibiotics display time-dependant pharmacodynamics whereby constant antibiotic concentrations rather than high peak concentrations are most likely to result in effective treatment of infections caused by susceptible bacteria. Continuous administration has been suggested as an alternative strategy, to conventional intermittent dosing, to optimise beta-lactam pharmacokinetic/pharmacodynamic (PK/PD) properties. With the availability of emerging data, we elected to systematically investigate the published literature describing the comparative PK/PD and clinical outcomes of beta-lactam antibiotics administered by continuous or intermittent infusion. We found that the studies have been performed in various patient populations including critically ill, cancer and cystic fibrosis patients. Available in vitro PK/PD data conclusively support the administration of beta-lactams via continuous infusion for maximizing bacterial killing from consistent attainment of pharmacodynamic end-points. In addition, clinical outcome data supports equivalence, even with the use of a lower dose by continuous infusion. However, the present clinical data is limited with small sample sizes common with insufficient power to detect advantages in favour of either dosing strategy. With abundant positive pre-clinical data as well as document in vivo PK/PD advantages, large multi-centre trials are needed to describe whether continuous administration of beta-lactams is truly more effective than intermittent dosing.

  15. Beta lactam antibiotics residues in cow’s milk: comparison of efficacy of three screening tests used in Bosnia and Herzegovina

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    Fejzić, Nihad; Begagić, Muris; Šerić-Haračić, Sabina; Smajlović, Muhamed

    2014-01-01

    Beta lactam antibiotics are widely used in therapy of cattle, particularly for the treatment of mastitis. Over 95% of residue testing in dairies in Bosnia and Herzegovina is for Beta lactams. The aim of this paper is to compare the efficacy of three most common screening tests for Beta lactam residues in cow’s milk in our country. The tests used in the study are SNAP β Lactam test (Idexx), Rosa Charm β Lactam test (Charm Sciences) and Inhibition MRL test (A&M). Study samples included: standardized concentrations of penicillin solution (0, 2, 3, 4, 5 and 6 ppb). In addition we tested milk samples from three equal size study groups (not receiving any antibiotic therapy, treated with Beta lactams for mastitis and treated with Beta lactams for diseases other than mastitis). Sensitivity and specificity were determined for each test, using standard penicillin concentrations with threshold value set at concentration of 4 ppb (Maximum residue level – MLR). Additionally we determined proportions of presumably false negative and false positive results for each test using results of filed samples testing. Agreement of test results for each test pair was assessed through Kappa coefficients interpreted by Landis-Koch scale. Detection level of all tests was shown to be well below MRL. This alongside with effects of natural inhibitors in milk contributed to finding of positive results in untreated and treated animals after the withholding period. Screening tests for beta lactam residues are important tools for ensuring that milk for human consumption is free from antibiotics residues. PMID:25172975

  16. A systematic review on clinical benefits of continuous administration of beta-lactam antibiotics.

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    Roberts, Jason A; Webb, Steven; Paterson, David; Ho, Kwok M; Lipman, Jeffrey

    2009-06-01

    The clinical benefits of extended infusion or continuous infusion of beta-lactam antibiotics remain controversial. We systematically reviewed the literature to determine whether any clinical benefits exist for administration of beta-lactam antibiotics by extended or continuous infusion. PubMed (January 1950 to November 2007), EMBASE (1966 to November 2007), and the Cochrane Controlled Trial Register were searched (updated November 2007). Randomized controlled trials (RCTs) were meta-analyzed, and observational studies were described by two unblinded reviewers. A total of 846 patients from eligible prospective randomized controlled studies were included in the meta-analysis. Two observational studies were deemed appropriate for description. A meta-analysis of prospective RCTs was undertaken using Review Manager. Among a total of 59 potentially relevant studies, 14 RCTs involving a total of 846 patients from nine countries were deemed appropriate for meta-analysis. The use of continuous infusion of a beta-lactam antibiotic was not associated with an improvement in clinical cure (n = 755 patients; odds ratio: 1.04, 95% confidence interval: 0.74-1.46, p = 0.83, I = 0%) or mortality (n = 541 patients; odds ratio: 1.00, 95% confidence interval: 0.48-2.06, p = 1.00, I = 14.8%). All RCTs except one used a higher antibiotic dose in the bolus administration group. Two observational studies, not pooled because they did not meet the a priori criteria for meta-analysis, showed that beta-lactam administration by extended or continuous infusion was associated with an improvement in clinical cure. The difference in the results between the meta-analysis results and the observational studies could be explained by the bias created by a higher dose of antibiotic in the bolus group in the RCTs and because many of the RCTs only recruited patients with a low acuity of illness. The limited data available suggest that continuous infusion of beta-lactam antibiotics leads to the same

  17. [Analysis of resistant genes of beta-lactam antibiotics from Pseudomonas aeruginosa in pediatric patients].

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    Dong, Fang; Xu, Xi-wei; Song, Wen-qi; Lü, Ping; Yang, Yong-hong; Shen, Xu-zhuang

    2008-11-18

    To analyze the antibiotic resistance of the Pseudomonas aeruginosa (PA) isolated from pediatric patients and the resistant genes of beta-lactam antibiotics thereof. 146 PA strains were isolated from pediatric patients. Agar dilution method recommended by the Clinical and Laboratory Standards Institute was used to examine the minimum inhibitory concentrations (MICs) of 12 antimicrobial agents, including the penicillins, third and fourth genet ration cephalosporins, carbapenemase, Aztreonam, beta-lactamase inhibitors, quinolones, and aminoglycosides. PCR was used to detect the expression of the genes TEM, SHV, OXA, PER, GES, CTX-M, IMP, VIM, DHA, MIR, FOX, and oprD2. The multi-drug resistance rates against different antibiotic were high among the 146 PA strains. The rates of imipenem and meropenem resistance were 41.1% and 35.6% respectively. Among the 146 PA strains, 46 (31.5%) were positive for the MBL genotype; 38 (82.6%) carried the blaIMP gene, 8 (17.4%) carried the blaVIM gene, and 114 (78.1%) were oprD2 negative. The genes TEM, SHV, OXA, CTX-M, PER, VEB, GES, FOX, MIR, and DHA were not found in all strains. Many PA isolated from pediatric patients carry the genes IMP or VIM and losses oprD2 gene related to the expression of the outer membrane porin OprD2. The loss of the gene oprD2 is essential mechanism of beta-lactam antibiotics resistance in PA.

  18. Desensitization in patients with beta-lactam drug allergy.

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    Yusin, J S; Klaustermeyer, W; Simmons, C W; Baum, M

    2013-01-01

    therapeutic courses of their antibiotic. Beta-lactam antibiotic sensitivity continues to present a challenging problem for physicians. Patients with drug resistant infections who are unable to obtain skin testing or who test positive to skin tests may need either a challenge or desensitization. Desensitization, saved for those with a convincing beta-lactam hypersensitivity history is often the choice of last resort given the associated cost and risk of anaphylaxis. However, once desensitization is complete, patients are usually able to tolerate full doses of antibiotics for full treatment length with minimal side effects. Published by Elsevier Espana.

  19. Paper analytical devices for fast field screening of beta lactam antibiotics and antituberculosis pharmaceuticals.

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    Weaver, Abigail A; Reiser, Hannah; Barstis, Toni; Benvenuti, Michael; Ghosh, Debarati; Hunckler, Michael; Joy, Brittney; Koenig, Leah; Raddell, Kellie; Lieberman, Marya

    2013-07-02

    Reports of low-quality pharmaceuticals have been on the rise in the past decade, with the greatest prevalence of substandard medicines in developing countries, where lapses in manufacturing quality control or breaches in the supply chain allow substandard medicines to reach the marketplace. Here, we describe inexpensive test cards for fast field screening of pharmaceutical dosage forms containing beta lactam antibiotics or combinations of the four first-line antituberculosis (TB) drugs. The devices detect the active pharmaceutical ingredients (APIs) ampicillin, amoxicillin, rifampicin, isoniazid, ethambutol, and pyrazinamide and also screen for substitute pharmaceuticals, such as acetaminophen and chloroquine that may be found in counterfeit pharmaceuticals. The tests can detect binders and fillers such as chalk, talc, and starch not revealed by traditional chromatographic methods. These paper devices contain 12 lanes, separated by hydrophobic barriers, with different reagents deposited in the lanes. The user rubs some of the solid pharmaceutical across the lanes and dips the edge of the paper into water. As water climbs up the lanes by capillary action, it triggers a library of different chemical tests and a timer to indicate when the tests are completed. The reactions in each lane generate colors to form a "color bar code" which can be analyzed visually by comparison with standard outcomes. Although quantification of the APIs is poor compared with conventional analytical methods, the sensitivity and selectivity for the analytes is high enough to pick out suspicious formulations containing no API or a substitute API as well as formulations containing APIs that have been "cut" with inactive ingredients.

  20. Frecuencia de enzimas asociadas a sensibilidad disminuida a betalactámicos en aislados de enterobacterias, Caracas, Venezuela Frequency of enzymes associated with reduced sensitivity to beta-lactam antibiotics in enterobacteria isolates, Caracas, Venezuela

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    Daniel Marcano

    2011-12-01

    ón adecuada de los perfiles de sensibilidad y la confirmación molecular del mecanismo presente.OBJECTIVE: To determine the frequency of enzymatic mechanisms associated with reduced sensitivity to broad-spectrum beta-lactam antibiotics in enterobacteria isolates obtained at hospital centers in Caracas, Venezuela. METHODS: A cross-sectional study was conducted on enterobacteria isolated from patients at eight hospital centers in Caracas, Venezuela, from 15 October 2009 to 15 January 2010. The species were identified using conventional biochemical tests, and their susceptibility to antimicrobial drugs was assessed by antibiogram (Kirby-Bauer method, using the 2010 performance standards published by the Clinical and Laboratory Standards Institute. Beta-lactam-resistant genes were detected using an enhanced polymerase chain reaction assay. RESULTS: Of 1 235 isolates, 207 (16.8% exhibited resistance to third- and fourth-generation cephalosporins, carbapenems, or both. They presented the following phenotypes: extended-spectrum beta-lactamase (ESBL, 93.8%; depressed AmpC, 4.3%; and carbapenemase, 1.9%. Further characterization of the first two phenotypes yielded the following breakdown of types: SHV, 36.7%; CTX-M-1 group, 22.3%; TEM, 21.7%; CTX-M-1 group with impermeability, 5.2%; two-enzyme combinations, 4.5%; CTX-M-2 group, 4.3%; PER, 3.4%; and KPC, 1.9%. The SHV type was predominant in the public hospital strains, whereas the CTX-M-1 group was most common in the strains from the private hospitals. CONCLUSIONS: Of the enzymatic mechanisms investigated, the SHV type was the most frequent, followed by the CTX-M-1 group and the TEM type. Also, a high percentage of type KPC was found. The research reported here is one of only a few multicenter studies that have been conducted in Venezuela to evaluate the frequency of this type of antimicrobial resistance mechanism, including phenotypical and molecular charac-terization. It was shown that the detection methods require proper

  1. Saturation mutagenesis reveals the importance of residues alpha R145 and alpha F146 of penicillin acylase in the synthesis of beta-lactam antibiotics

    NARCIS (Netherlands)

    Jager, Simon A. W.; Shapovalova, Irina V.; Jekel, Peter A.; Alkema, Wynand B. L.; Svedas, Vytas K.; Janssen, Dick B.; Švedas, Vytas K.

    2008-01-01

    Penicillin acylase (PA) from Escherichia coli can catalyze the coupling of an acyl group to penicillin- and cephalosporin-derived beta-lactam nuclei, a conversion that can be used for the industrial synthesis of beta-lactam. antibiotics. The modest synthetic properties of the wild-type enzyme make

  2. Subinhibitory Concentrations of Bacteriostatic Antibiotics Induce relA-Dependent and relA-Independent Tolerance to beta-Lactams

    Czech Academy of Sciences Publication Activity Database

    Kudrin, P.; Varik, V.; Oliveira, S. R. A.; Beljantseva, J.; Del Peso Santos, T.; Dzhygyr, I.; Rejman, Dominik; Cava, F.; Tenson, T.; Hauryliuk, V.

    2017-01-01

    Roč. 61, č. 4 (2017), č. článku e02173-16. ISSN 0066-4804 R&D Projects: GA ČR GA15-11711S Institutional support: RVO:61388963 Keywords : beta-lactam * RelA * antibiotics * mupirocin * persistence * ppGpp Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.302, year: 2016 http://aac.asm.org/content/61/4/e02173-16.full

  3. Beta- Lactam Antibiotics Stimulate Biofilm Formation in Non-Typeable Haemophilus influenzae by Up-Regulating Carbohydrate Metabolism

    Science.gov (United States)

    Wu, Siva; Li, Xiaojin; Gunawardana, Manjula; Maguire, Kathleen; Guerrero-Given, Debbie; Schaudinn, Christoph; Wang, Charles; Baum, Marc M.; Webster, Paul

    2014-01-01

    Non-typeable Haemophilus influenzae (NTHi) is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth) stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL) of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended. PMID:25007395

  4. Beta- lactam antibiotics stimulate biofilm formation in non-typeable haemophilus influenzae by up-regulating carbohydrate metabolism.

    Directory of Open Access Journals (Sweden)

    Siva Wu

    Full Text Available Non-typeable Haemophilus influenzae (NTHi is a common acute otitis media pathogen, with an incidence that is increased by previous antibiotic treatment. NTHi is also an emerging causative agent of other chronic infections in humans, some linked to morbidity, and all of which impose substantial treatment costs. In this study we explore the possibility that antibiotic exposure may stimulate biofilm formation by NTHi bacteria. We discovered that sub-inhibitory concentrations of beta-lactam antibiotic (i.e., amounts that partially inhibit bacterial growth stimulated the biofilm-forming ability of NTHi strains, an effect that was strain and antibiotic dependent. When exposed to sub-inhibitory concentrations of beta-lactam antibiotics NTHi strains produced tightly packed biofilms with decreased numbers of culturable bacteria but increased biomass. The ratio of protein per unit weight of biofilm decreased as a result of antibiotic exposure. Antibiotic-stimulated biofilms had altered ultrastructure, and genes involved in glycogen production and transporter function were up regulated in response to antibiotic exposure. Down-regulated genes were linked to multiple metabolic processes but not those involved in stress response. Antibiotic-stimulated biofilm bacteria were more resistant to a lethal dose (10 µg/mL of cefuroxime. Our results suggest that beta-lactam antibiotic exposure may act as a signaling molecule that promotes transformation into the biofilm phenotype. Loss of viable bacteria, increase in biofilm biomass and decreased protein production coupled with a concomitant up-regulation of genes involved with glycogen production might result in a biofilm of sessile, metabolically inactive bacteria sustained by stored glycogen. These biofilms may protect surviving bacteria from subsequent antibiotic challenges, and act as a reservoir of viable bacteria once antibiotic exposure has ended.

  5. Resistance of Pseudomonas aeruginosa PAO to nalidixic acid and low levels of beta-lactam antibiotics: mapping of chromosomal genes.

    Science.gov (United States)

    Rella, M; Haas, D

    1982-01-01

    Resistance to high concentrations of nalidixic acid in Pseudomonas aeruginosa PAO was due to mutations in one locus designated nalA, which was mapped by transduction between hex-9001 and leu-10. The nalA mutants were cross-resistant to pipemidic acid, a nalidixic acid analog, at relatively low concentrations. Replicative DNA synthesis was resistant to both drugs in permeabilized cells of nalA mutants. A locus coding for low-level resistance to nalidixic acid, nalB, was cotransducible with pyrB, proC, and met-28. The nalB mutants were also resistant to low levels of pipemidic acid, novobiocin, and beta-lactam antibiotics (e.g., carbenicillin, azlocillin, and cefsulodin), but not to other drugs, such as gentamicin, rifampin, kanamycin, or tetracycline. In nalB mutants, DNA replication showed wild-type sensitivity to nalidixic acid, whereas carbenicillin-induced filamentation required higher drug levels than in the wild-type strain. Thus, nalB mutations appear to decrease cell permeability to some antibiotics. The sensitivity of replicative DNA synthesis to nalidixic acid and novobiocin was very similar in P. aeruginosa and Escherichia coli; by contrast, the concentrations of these drugs needed to inhibit growth of P. aeruginosa were higher than those reported for E. coli by one or two orders of magnitude. PMID:6821455

  6. A rapid two-step algorithm detects and identifies clinical macrolide and beta-lactam antibiotic resistance in clinical bacterial isolates.

    Science.gov (United States)

    Lu, Xuedong; Nie, Shuping; Xia, Chengjing; Huang, Lie; He, Ying; Wu, Runxiang; Zhang, Li

    2014-07-01

    Aiming to identify macrolide and beta-lactam resistance in clinical bacterial isolates rapidly and accurately, a two-step algorithm was developed based on detection of eight antibiotic resistance genes. Targeting at genes linked to bacterial macrolide (msrA, ermA, ermB, and ermC) and beta-lactam (blaTEM, blaSHV, blaCTX-M-1, blaCTX-M-9) antibiotic resistances, this method includes a multiplex real-time PCR, a melting temperature profile analysis as well as a liquid bead microarray assay. Liquid bead microarray assay is applied only when indistinguishable Tm profile is observed. The clinical validity of this method was assessed on clinical bacterial isolates. Among the total 580 isolates that were determined by our diagnostic method, 75% of them were identified by the multiplex real-time PCR with melting temperature analysis alone, while the remaining 25% required both multiplex real-time PCR with melting temperature analysis and liquid bead microarray assay for identification. Compared with the traditional phenotypic antibiotic susceptibility test, an overall agreement of 81.2% (kappa=0.614, 95% CI=0.550-0.679) was observed, with a sensitivity and specificity of 87.7% and 73% respectively. Besides, the average test turnaround time is 3.9h, which is much shorter in comparison with more than 24h for the traditional phenotypic tests. Having the advantages of the shorter operating time and comparable high sensitivity and specificity with the traditional phenotypic test, our two-step algorithm provides an efficient tool for rapid determination of macrolide and beta-lactam antibiotic resistances in clinical bacterial isolates. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Trace determination of 10 beta-lactam antibiotics in environmental and food samples by capillary liquid chromatography.

    Science.gov (United States)

    Bailón-Pérez, M I; García-Campaña, A M; del Olmo-Iruela, M; Gámiz-Gracia, L; Cruces-Blanco, C

    2009-11-20

    A sensitive and reliable method using capillary HPLC with UV-diode array detection (DAD) has been developed and validated for the trace determination of residues of 10 beta-lactam antibiotics of human and veterinary use, in milk, chicken meat and environmental water samples. The analytes included ampicillin, amoxicillin, penicillin V, penicillin G, cloxacillin, oxacillin, dicloxacillin, nafcillin, piperacillin and clavulanic acid. Legal levels are regulated by the EU Council regulation 2377/90 in animal edible tissues for these compounds. For food analysis, a solid-phase extraction (SPE) procedure consisting in a tandem of Oasis HLB and Alumina N cartridges was applied for off-line preconcentration and cleanup. For water analysis, the first step was only necessary. The limits of detection for the studied compounds were between 0.04-0.06 microg l(-1) for water samples and 0.80-1.40 microg l(-1) (or microg kg(-1)) in the case of foods derived from animals. Average recoveries for fortified samples at different concentration levels ranged between 82.9% and 98.2%, with relative standard deviations (RSDs) lower than 9%. The method showed the advantages of capillary HPLC for the detection of these widely applied antibiotics in different samples at very low concentration levels.

  8. Effects of beta-lactamases and omp mutation on susceptibility to beta-lactam antibiotics in Escherichia coli.

    Science.gov (United States)

    Hiraoka, M; Okamoto, R; Inoue, M; Mitsuhashi, S

    1989-01-01

    Four types of beta-lactamases consisting of a penicillinase type I (TEM-1), a penicillinase type II (OXA-1), a cephalosporinase of Citrobacter freundii, and a cephalosporinase of Proteus vulgaris were introduced into Escherichia coli MC4100 and its omp mutants, MH1160 (MC4100 ompR1) and MH760 (MC4100 ompR2), by transformation. Effects of the combination of the omp mutations and these beta-lactamases on the susceptibility of E. coli strains were studied with 15 beta-lactam antibiotics including cephalosporins, cephamycins, penicillins, imipenem, and aztreonam. The ompR1 mutant, MH1160, lacks OmpF and OmpC, and it showed reduced susceptibility to 11 of the 15 beta-lactam agents. The reduction in susceptibility to cefoxitin, moxalactam, and flomoxef was much greater than reduction in susceptibility to the other agents. When the ompR1 mutant produced the cephalosporinase of C. freundii, the susceptibility of the mutant to 12 of the 15 beta-lactam antibiotics decreased. The reduction in susceptibility of MH1160 to 10 of the 12 agents affected by the enzyme was two- to fourfold greater than that observed in MC4100. Such a synergistic effect was also observed with the cephalosporinase of P. vulgaris and ompR1 mutation against six cephalosporins, moxalactam, and aztreonam. Images PMID:2658786

  9. High-dose continuous infusion beta-lactam antibiotics for the treatment of resistant Pseudomonas aeruginosa infections in immunocompromised patients.

    Science.gov (United States)

    Moriyama, Brad; Henning, Stacey A; Childs, Richard; Holland, Steven M; Anderson, Victoria L; Morris, John C; Wilson, Wyndham H; Drusano, George L; Walsh, Thomas J

    2010-05-01

    To report a case series of high-dose continuous infusion beta-lactam antibiotics for the treatment of resistant Pseudomonas aeruginosa infections. Continuous infusion ceftazidime or aztreonam was administered to achieve target drug concentrations at or above the minimum inhibitory concentration, when possible, in 3 patients with P. aeruginosa infections. The maximal calculated target drug concentration was 100 mg/L. In the first patient, with primary immunodeficiency, neutropenia, and aggressive cutaneous T-cell lymphoma/leukemia, continuous infusion ceftazidime (6.5-9.6 g/day) was used to successfully treat multidrug-resistant P. aeruginosa bacteremia. In the second patient, with leukocyte adhesion deficiency type 1, continuous infusion aztreonam (8.4 g/day) was used to successfully treat multidrug-resistant P. aeruginosa wound infections. In the third patient, with severe aplastic anemia, continuous infusion ceftazidime (7-16.8 g/day) was used to treat P. aeruginosa pneumonia and bacteremia. In each patient, bacteremia cleared, infected wounds healed, and pneumonia improved in response to continuous infusion ceftazidime or aztreonam. Treatment strategies for multidrug-resistant P. aeruginosa infections are limited. A novel treatment strategy, when no other options are available, is the continuous infusion of existing beta-lactam antibiotics to maximize their pharmacodynamic activity. High-dose continuous infusion ceftazidime or aztreonam was used for the successful treatment of resistant systemic P. aeruginosa infections in 3 chronically immunocompromised patients. Continuous infusion beta-lactam antibiotics are a potentially useful treatment strategy for resistant P. aeruginosa infections in immunocompromised patients.

  10. Metallo-beta-lactamases of Pseudomonas aeruginosa--a novel mechanism resistance to beta-lactam antibiotics.

    Directory of Open Access Journals (Sweden)

    Dorota Olszańska

    2008-06-01

    Full Text Available Since about twenty years, following the introduction into therapeutic of news beta-lactam antibiotics (broad-spectrum cephalosporins, monobactams and carbapenems, a very significant number of new beta-lactamases appeared. These enzymes confer to the bacteria which put them, the means of resisting new molecules. The genetic events involved in this evolution are of two types: evolution of old enzymes by mutation and especially appearance of new genes coming for some, from bacteria of the environment. Numerous mechanisms of enzymatic resistance to the carbapenems have been described in Pseudomonas aeruginosa. The important mechanism of inactivation carbapenems is production variety of b-lactam hydrolysing enzymes associated to carbapenemases. The metallo-beta-enzymes (IMP, VIM, SPM, GIM types are the most clinically significant carbapenemases. P. aeruginosa posses MBLs and seem to have acquired them through transmissible genetic elements (plasmids or transposons associated with integron and can be transmission to other bacteria. They have reported worldwide but mostly from South East Asia and Europe. The enzymes, belonging to the molecular class B family, are the most worrisome of all beta-lactamases because they confer resistance to carbapenems and all the beta-lactams (with the exception of aztreonam and usually to aminoglycosides and quinolones. The dissemination of MBLs genes is thought to be driven by regional consumption of extended--spectrum antibiotics (e.g. cephalosporins and carbapenems, and therefore care must be taken that these drugs are not used unnecessarily.

  11. Analysis of profitability in the diagnosis of allergy to beta-lactam antibiotics.

    Science.gov (United States)

    Ferré-Ybarz, L; Salinas Argente, R; Gómez Galán, C; Duocastella Selvas, P; Nevot Falcó, S

    2015-01-01

    Drug allergy is the third most common reason for allergy consultations. There is a tendency to call any adverse drug reaction (ADR) allergic, even without confirmatory allergy study. (1) Evaluate time of resolution allergy to beta-lactam's study in a sample of 100 patients. (2) Analyse cost-effectiveness of current diagnostic study (skin tests, specific IgE and drug provocation test (DPT)). (3) Describe type and frequency of ADRs in adult/paediatric patients. (4) Compare cost of complete study with DPT. (5) Assess the need to restructure current study methodology according to results obtained. The study is part of a strategic plan of the allergy department (2005-2010). Patients with suspected allergy to beta-lactams were included. Procedures performed: medical history, specific IgE, skin tests and DPT. Cost/patient analysis. Cost of protocol analysis for current diagnostic/direct DPT. 100 patients were studied, 52 females/48 males; 43 children/57 adults. 89 cutaneous, 4 anaphylaxis, 3 vasovagal reactions, 6 non-specific symptoms and 4 not recalled. Allergy was confirmed in six patients (only one child). Complete-study cost: 149.3 Euros/patient. DPT-study cost: 97.19 Euros/patient (34.9% less). Resolution time 9-13 months, absenteeism 28.04%. In the series studied, diagnosis of allergy to beta-lactams was confirmed in 6% of patients (2.3% of paediatric patients). After analysing results and cost of the study we believe that we should propose a specific diagnostic algorithm in those paediatric patients without suspected IgE-mediated ADR, and for those patients direct DPT should be conducted. This will reduce cost/patient (-34.9%), time of resolution and absenteeism. Copyright © 2014 SEICAP. Published by Elsevier Espana. All rights reserved.

  12. Development of a novel and automated fluorescent immunoassay for the analysis of beta-lactam antibiotics

    NARCIS (Netherlands)

    Benito-Pena, E.; Moreno-Bondi, M.C.; Orellana, G.; Maquieira, K.; Amerongen, van A.

    2005-01-01

    An automated immunosensor for the rapid and sensitive analysis of penicillin type -lactam antibiotics has been developed and optimized. An immunogen was prepared by coupling the common structure of the penicillanic -lactam antibiotics, i.e., 6-aminopenicillanic acid to keyhole limpet hemocyanin.

  13. Penicillin G acylase from Achromobacter sp CCM 4824 An efficient biocatalyst for syntheses of beta-lactam antibiotics under conditions employed in large-scale processes

    Czech Academy of Sciences Publication Activity Database

    Bečka, Stanislav; Štěpánek, Václav; Vyasarayani, W. R.; Grulich, Michal; Maršálek, Jaroslav; Plháčková, Kamila; Dobišová, Marie; Marešová, Helena; Plačková, Martina; Valešová, Renata; Palyzová, Andrea; Datla, A.; Ashar, T. K.; Kyslík, Pavel

    2014-01-01

    Roč. 98, č. 3 (2014), s. 1195-1203 ISSN 0175-7598 Institutional support: RVO:61388971 Keywords : Achromobacter sp. * Penicillin G acylase * beta-Lactam antibiotics Subject RIV: EE - Microbiology, Virology Impact factor: 3.337, year: 2014

  14. In vitro interactions between different beta-lactam antibiotics and fosfomycin against bloodstream isolates of enterococci.

    Science.gov (United States)

    Pestel, M; Martin, E; Aucouturier, C; Lemeland, J F; Caron, F

    1995-01-01

    The effects of 16 different beta-lactam-fosfomycin combinations against 50 bloodstream enterococci were compared by a disk diffusion technique. Cefotaxime exhibited the best interaction. By checkerboard studies, the cefotaxime-fosfomycin combination provided a synergistic bacteriostatic effect against 45 of the 50 isolates (MIC of cefotaxime at which 90% of the isolates were inhibited, >2,048 micrograms/ml; MIC of fosfomycin at which 90% of the isolates were inhibited, 128 micrograms/ml; mean of fractional inhibitory concentration indexes, 0.195). By killing curves, cefotaxime (at 64 micrograms/ml) combined with fosfomycin (at > or = 64 micrograms/ml) was bactericidal against 6 of 10 strains tested. PMID:8619593

  15. Synthetic Beta-Lactam Antibiotic as a Selective Breast Cancer Cell Apoptosis Inducer: Significance in Breast Cancer Prevention and Treatment

    Science.gov (United States)

    2005-04-01

    methylthiolated beta-lactams has been discovered that have potent activity against methicillin resistant Staphylococcus aureas . Most recently, we...2.40 (s, 3H); 13C NMR (CDCI3, 63 MHz) 6 170.4, 133.8, 131.4, 129.6, 128.9, 126.8, 86.7, 62.7, 58.9, 21.8. See References 15-20. This section is... section is directly related to Task 1 outlined in the Statement of Work, "To evaluate requirements of the C3 ring substituents of beta-lactams as a

  16. Zinc Finger Nuclease: A New Approach to Overcome Beta-Lactam Antibiotic Resistance

    Science.gov (United States)

    Shahbazi Dastjerdeh, Mansoureh; Kouhpayeh, Shirin; Sabzehei, Faezeh; Khanahmad, Hossein; Salehi, Mansour; Mohammadi, Zahra; Shariati, Laleh; Hejazi, Zahra; Rabiei, Parisa; Manian, Mostafa

    2016-01-01

    Background: The evolution of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) has been accelerated recently by the indiscriminate application of antibiotics. Antibiotic resistance has challenged the success of medical interventions and therefore is considered a hazardous threat to human health. Objectives: The present study aimed to describe the use of zinc finger nuclease (ZFN) technology to target and disrupt a plasmid-encoded β-lactamase, which prevents horizontal gene transfer-mediated evolution of ARBs. Materials and Methods: An engineered ZFN was designed to target a specific sequence in the ampicillin resistance gene (ampR) of the pTZ57R plasmid. The Escherichia coli bacteria already contained the pZFN kanamycin-resistant (kanaR) plasmid as the case or the pP15A, kanaR empty vector as the control, were transformed with the pTZ57R; the ability of the designed ZFN to disrupt the β-lactamase gene was evaluated with the subsequent disturbed ability of the bacteria to grow on ampicillin (amp) and ampicillin-kanamycin (amp-kana)-containing media. The effect of mild hypothermia on the ZFN gene targeting efficiency was also evaluated. Results: The growth of bacteria in the case group on the amp and amp-kana-containing media was significantly lower compared with the control group at 37°C (P < 0.001). Despite being more efficient in hypothermic conditions at 30°C (P < 0.001), there were no significant associations between the incubation temperature and the ZFN gene targeting efficiency. Conclusions: Our findings revealed that the ZFN technology could be employed to overcome ampicillin resistance by the targeted disruption of the ampicillin resistance gene, which leads to inactivation of β-lactam synthesis. Therefore, ZFN technology could be engaged to decrease the antibiotic resistance issue with the construction of a ZFN archive against different ARGs. To tackle the resistance issue at the environmental level, recombinant phages

  17. Beta-lactam antibiotic-induced platelet dysfunction: Evidence for irreversible inhibition of platelet activation in vitro and in vivo after prolonged exposure to penicillin

    International Nuclear Information System (INIS)

    Burroughs, S.F.; Johnson, G.J.

    1990-01-01

    beta-Lactam antibiotics cause platelet dysfunction with bleeding complications. Previous in vitro studies documented reversible inhibition of agonist-receptor interaction. This mechanism is inadequate to explain the effect of beta-lactam antibiotics in vivo. Platelet function does not return to normal immediately after drug treatment, implying irreversible inhibition of platelet function. We report here evidence of irreversible platelet functional and biochemical abnormalities after in vitro and in vivo exposure to beta-lactam antibiotics. Irreversible binding of [14C]-penicillin (Pen) occurred in vitro. After 24 hours' in vitro incubation with 10 to 20 mmol/L Pen, or ex vivo after antibiotic treatment, irreversible functional impairment occurred; but no irreversible inhibition of alpha 2 adrenergic receptors, measured with [3H]-yohimbine, or high-affinity thromboxane A2/prostaglandin H2 (TXA2/PGH2) receptors, measured with agonist [3H]-U46619 and antagonist [3H]-SQ29548, occurred. However, low-affinity platelet TXA2/PGH2 receptors were decreased 40% after Pen exposure in vitro or in vivo, indicating irreversible membrane alteration. Two postreceptor biochemical events were irreversibly inhibited in platelets incubated with Pen for 24 hours in vitro or ex vivo after antibiotic treatment. Thromboxane synthesis was inhibited 28.3% to 81.7%. Agonist-induced rises in cytosolic calcium ([Ca2+]i) were inhibited 40.1% to 67.5% in vitro and 26.6% to 52.2% ex vivo. Therefore, Pen binds to platelets after prolonged exposure, resulting in irreversible dysfunction attributable to inhibition of TXA2 synthesis and impairment of the rise in [Ca2+]i. The loss of low-affinity TXA2/PGH2 receptors suggests that the primary site of action of these drugs is on the platelet membrane

  18. Designing Predictive Models for Beta-Lactam Allergy Using the Drug Allergy and Hypersensitivity Database.

    Science.gov (United States)

    Chiriac, Anca Mirela; Wang, Youna; Schrijvers, Rik; Bousquet, Philippe Jean; Mura, Thibault; Molinari, Nicolas; Demoly, Pascal

    Beta-lactam antibiotics represent the main cause of allergic reactions to drugs, inducing both immediate and nonimmediate allergies. The diagnosis is well established, usually based on skin tests and drug provocation tests, but cumbersome. To design predictive models for the diagnosis of beta-lactam allergy, based on the clinical history of patients with suspicions of allergic reactions to beta-lactams. The study included a retrospective phase, in which records of patients explored for a suspicion of beta-lactam allergy (in the Allergy Unit of the University Hospital of Montpellier between September 1996 and September 2012) were used to construct predictive models based on a logistic regression and decision tree method; a prospective phase, in which we performed an external validation of the chosen models in patients with suspicion of beta-lactam allergy recruited from 3 allergy centers (Montpellier, Nîmes, Narbonne) between March and November 2013. Data related to clinical history and allergy evaluation results were retrieved and analyzed. The retrospective and prospective phases included 1991 and 200 patients, respectively, with a different prevalence of confirmed beta-lactam allergy (23.6% vs 31%, P = .02). For the logistic regression method, performances of the models were similar in both samples: sensitivity was 51% (vs 60%), specificity 75% (vs 80%), positive predictive value 40% (vs 57%), and negative predictive value 83% (vs 82%). The decision tree method reached a sensitivity of 29.5% (vs 43.5%), specificity of 96.4% (vs 94.9%), positive predictive value of 71.6% (vs 79.4%), and negative predictive value of 81.6% (vs 81.3%). Two different independent methods using clinical history predictors were unable to accurately predict beta-lactam allergy and replace a conventional allergy evaluation for suspected beta-lactam allergy. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  19. Ceftriaxone, a beta-lactam antibiotic, reduces ethanol consumption in alcohol-preferring rats.

    Science.gov (United States)

    Sari, Youssef; Sakai, Makiko; Weedman, Jason M; Rebec, George V; Bell, Richard L

    2011-01-01

    Changes in glutamatergic transmission affect many aspects of neuroplasticity associated with ethanol and drug addiction. For instance, ethanol- and drug-seeking behavior is promoted by increased glutamate transmission in key regions of the motive circuit. We hypothesized that because glutamate transporter 1 (GLT1) is responsible for the removal of most extracellular glutamate, up-regulation or activation of GLT1 would attenuate ethanol consumption. Alcohol-preferring (P) rats were given 24 h/day concurrent access to 15 and 30% ethanol, water and food for 7 weeks. During Week 6, P rats received either 25, 50, 100 or 200 mg/kg ceftriaxone (CEF, i.p.), a β-lactam antibiotic known to elevate GLT1 expression, or a saline vehicle for five consecutive days. Water intake, ethanol consumption and body weight were measured daily for 15 days starting on Day 1 of injections. We also tested the effects of CEF (100 and 200 mg/kg, i.p.) on daily sucrose (10%) consumption as a control for motivated behavioral drinking. Statistical analyses revealed a significant reduction in daily ethanol, but not sucrose, consumption following CEF treatment. During the post treatment period, there was a recovery of ethanol intake across days. Dose-dependent increases in water intake were manifest concurrent with the CEF-induced decreases in ethanol intake. Nevertheless, CEF did not affect body weight. An examination of a subset of the CEF-treated ethanol-drinking rats, on the third day post CEF treatment, revealed increases in GTL1 expression levels within the prefrontal cortex and nucleus accumbens. These results indicate that CEF effectively reduces ethanol intake, possibly through activation of GLT1, and may be a potential therapeutic drug for alcohol addiction treatment.

  20. [Beta-lactamic antibiotics allergy in cataract surgery. Prevalence and preoperative characteristics of allergic patients].

    Science.gov (United States)

    Fernández-Rubio, M E; Cuesta-Rodríguez, T; Urcelay-Segura, J L; Cortés-Valdés, C

    2014-03-01

    To describe the proportion of patients allergic to β-lactam antibiotics and the prevalence of preoperative conjunctival bacteria among those undergoing cataract surgery in our area. Retrospective cross-sectional study of prevalence of β-lactam allergic patients consecutively scheduled for cataract surgery from 11 July 2005 to November 2012. For studying the prevalence of conjunctival bacteria and clinical characteristics in the patients' preoperative examination, those under 18 years and those with cataract surgery combined with other eye surgeries were excluded. Data from the first preoperative examination of the remaining patients were selected. Clinical data were extracted from the database generated in the evaluation made for anesthetic purposes, and the microbiological data from the laboratory database. Both bases were linked through a patient history code. A comparison was made between the prevalence of conjunctival bacteria and clinical characteristics in allergic and non-allergic patients. From 12,409 adults selected for the bacteriological study, 862 (6.96%) were allergic to β-lactams, their mean age (74.45 years) was higher than that of the non-allergic (P=.005). The proportion of women (71.4%) in the allergic patient group was much higher than that of men. The prevalence of pathogenic bacteria (especially Bacillus spp and Pseudomonas aeruginosa), lung disease and heart failure, was higher in allergic patients. The prevalence of allergy to β-lactams in this study is within the range described in other populations. The higher prevalence of pathogenic bacteria and the predominance of women in those allergic to β-lactams are useful data to guide their surgical prophylaxis. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  1. [Beta lactam antibiotics and the question of dose regimen for severe infection. Prolonged infusion theoretically appealing--yet no evidence of clinical benefit].

    Science.gov (United States)

    Leander, Gunilla; Eliasson, Erik; Hanberger, Håkan; Giske, Christian

    2015-03-24

    Patients with severe sepsis/septic shock have a high mortality. Beta-lactam antibiotics are normally first line treatment. This antimicrobial class has been associated with time-dependent efficacy. It is therefore plausible that administration as prolonged infusion will increase the therapeutic effect, as compared to short term bolus injections, which is the most common practice today. We have reviewed 14 randomized controlled studies to investigate whether prolonged infusion provides lower mortality and/or increased clinical cure. In summary, convincing advantages with prolonged infusion could not be found, however randomized studies are heterogeneous, and it cannot be excluded that some subgroups of critically ill patients could benefit from such treatment.

  2. Draft genome sequence of Pantoea agglomerans JM1, a strain isolated from soil polluted by industrial production of Beta-Lactam antibiotics that exhibits valacyclovir-like hydrolase activity

    Czech Academy of Sciences Publication Activity Database

    Zahradník, Jiří; Plačková, Martina; Palyzová, Andrea; Marešová, Helena; Kyslíková, Eva; Kyslík, Pavel

    2017-01-01

    Roč. 5, č. 38 (2017), č. článku e00921-17. ISSN 2169-8287 Institutional support: RVO:61388971 Keywords : 6 nitro 3 (phenylacetamido)benzoic acid * beta lactam antibiotic * topoisomerase (ATP hydrolysing) B Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology

  3. Activities of beta-lactam antibiotics against Escherichia coli strains producing extended-spectrum beta-lactamases.

    Science.gov (United States)

    Jacoby, G A; Carreras, I

    1990-01-01

    Seven extended-spectrum beta-lactamases related to TEM and four enzymes derived from SHV-1 were transferred to a common Escherichia coli host so that the activity of a variety of beta-lactams could be tested in a uniform genetic environment. For most derivatives, penicillinase activity was 10% or less than that of strains making TEM-1, TEM-2, or SHV-1 beta-lactamase, suggesting that reduced catalytic efficiency accompanied the broader substrate spectrum. Despite this deficit, resistance to aztreonam, carumonam, cefdinir, cefepime, cefixime, cefmenoxime, cefotaxime, cefotiam, cefpirome, cefpodoxime, ceftazidime, ceftibuten, ceftizoxime, ceftriaxone, cefuroxime, and E1040 was enhanced. For strains producing TEM-type enzymes, however, MICs of carumonam, cefepime, cefmenoxime, cefotiam, cefpirome, and ceftibuten were 8 micrograms/ml or less. Susceptibilities of cefmetazole, cefotetan, cefoxitin, flomoxef, imipenem, meropenem, moxalactam, temocillin, FCE 22101, and Sch 34343 were unaffected. FCE 22101, imipenem, meropenem, and Sch 34343 were inhibitory for all strains at 1 microgram/ml or less. In E. coli an OmpF- porin mutation in combination with an extended-spectrum beta-lactamase enhanced resistance to many of these agents, but generally by only fourfold. Hyperproduction of chromosomal AmpC beta-lactamase increased resistance to 7-alpha-methoxy beta-lactams but not that to temocillin. When tested at 8 micrograms/ml, clavulanate was more potent than sulbactam or tazobactam in overcoming resistance to ampicillin, while cefoperazone-sulbactam was more active than ticarcillin-clavulanate or piperacillin-tazobactam, especially against TEM-type extended-spectrum beta-lactamases. PMID:2193623

  4. CesRK, a two-component signal transduction system in Listeria monocytogenes, responds to the presence of cell wall-acting antibiotics and affects beta-lactam resistance

    DEFF Research Database (Denmark)

    Kallipolitis, Birgitte H; Ingmer, Hanne; Gahan, Cormac G

    2003-01-01

    Listeria monocytogenes is a food-borne pathogen that can cause a variety of illnesses ranging from gastroenteritis to life-threatening septicemia. The beta-lactam antibiotic ampicillin remains the drug of choice for the treatment of listeriosis. We have previously identified a response regulator...... of L. monocytogenes to tolerate ethanol and cell wall-acting antibiotics of the beta-lactam family. Furthermore, CesRK controls the expression of a putative extracellular peptide encoded by the orf2420 gene, located immediately downstream from cesRK. Inactivation of orf2420 revealed that it contributes...... to ethanol tolerance and pathogenesis in mice. Interestingly, we found that transcription of orf2420 was strongly induced by subinhibitory concentrations of various cell wall-acting antibiotics, ethanol, and lysozyme. The induction of orf2420 expression was abolished in the absence of CesRK. Our data suggest...

  5. Comprehensive identification of single nucleotide polymorphisms associated with beta-lactam resistance within pneumococcal mosaic genes.

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    Claire Chewapreecha

    2014-08-01

    Full Text Available Traditional genetic association studies are very difficult in bacteria, as the generally limited recombination leads to large linked haplotype blocks, confounding the identification of causative variants. Beta-lactam antibiotic resistance in Streptococcus pneumoniae arises readily as the bacteria can quickly incorporate DNA fragments encompassing variants that make the transformed strains resistant. However, the causative mutations themselves are embedded within larger recombined blocks, and previous studies have only analysed a limited number of isolates, leading to the description of "mosaic genes" as being responsible for resistance. By comparing a large number of genomes of beta-lactam susceptible and non-susceptible strains, the high frequency of recombination should break up these haplotype blocks and allow the use of genetic association approaches to identify individual causative variants. Here, we performed a genome-wide association study to identify single nucleotide polymorphisms (SNPs and indels that could confer beta-lactam non-susceptibility using 3,085 Thai and 616 USA pneumococcal isolates as independent datasets for the variant discovery. The large sample sizes allowed us to narrow the source of beta-lactam non-susceptibility from long recombinant fragments down to much smaller loci comprised of discrete or linked SNPs. While some loci appear to be universal resistance determinants, contributing equally to non-susceptibility for at least two classes of beta-lactam antibiotics, some play a larger role in resistance to particular antibiotics. All of the identified loci have a highly non-uniform distribution in the populations. They are enriched not only in vaccine-targeted, but also non-vaccine-targeted lineages, which may raise clinical concerns. Identification of single nucleotide polymorphisms underlying resistance will be essential for future use of genome sequencing to predict antibiotic sensitivity in clinical microbiology.

  6. Investigation of the sensitising and cross-sensitising potential of textile dyes and beta-lactam antibiotics using a biphasic mice local lymph node assay.

    Science.gov (United States)

    Ahuja, Varun; Schreiber, Clemens; Platzek, Thomas; Stahlmann, Ralf

    2009-07-01

    We used a modified protocol of the murine local lymph node assay (LLNA) to study the cross-sensitising potential of (a) textile dye disperse yellow 3 and its metabolite 2-amino-p-cresol, (b) two antibiotics, penicillin G and cefotiam. The test substances were applied in a biphasic manner, i.e. first on the shaved skin of the back followed by application on the dorsal side of the ears after 2 weeks. The end-points analysed included thickness and weight of an ear-biopsy, weight and cell number of the draining lymph node, and lymphocyte cell surface markers analysed by flow-cytometry. Disperse yellow 3 and its metabolite significantly altered the various end-points at both the tested concentrations (0.5 and 1%), thus demonstrating the sensitising potential of the two substances. The cross-sensitisation study showed significant modulation in the tested variables in the treated group as compared to the control, signifying cross-sensitisation potential of the two substances. Penicillin G and cefotiam showed significant changes in various end-points, pointing towards their sensitising potential. However, even at 50% concentration of the beta-lactams no significant change in any end-point indicating absence of cross-reactivity of the antibiotics was noticed. We conclude that a biphasic, modified protocol of the LLNA is a suitable approach to test for a cross-reactivity potential of two related compounds.

  7. Abundances of tetracycline, sulphonamide and beta-lactam antibiotic resistance genes in conventional wastewater treatment plants (WWTPs with different waste load.

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    Mailis Laht

    Full Text Available Antibiotics and antibiotic resistant bacteria enter wastewater treatment plants (WWTPs, an environment where resistance genes can potentially spread and exchange between microbes. Several antibiotic resistance genes (ARGs were quantified using qPCR in three WWTPs of decreasing capacity located in Helsinki, Tallinn, and Tartu, respectively: sulphonamide resistance genes (sul1 and sul2, tetracycline resistance genes (tetM and tetC, and resistance genes for extended spectrum beta-lactams (blaoxa-58, blashv-34, and blactx-m-32. To avoid inconsistencies among qPCR assays we normalised the ARG abundances with 16S rRNA gene abundances while assessing if the respective genes increased or decreased during treatment. ARGs were detected in most samples; sul1, sul2, and tetM were detected in all samples. Statistically significant differences (adjusted p<0.01 between the inflow and effluent were detected in only four cases. Effluent values for blaoxa-58 and tetC decreased in the two larger plants while tetM decreased in the medium-sized plant. Only blashv-34 increased in the effluent from the medium-sized plant. In all other cases the purification process caused no significant change in the relative abundance of resistance genes, while the raw abundances fell by several orders of magnitude. Standard water quality variables (biological oxygen demand, total phosphorus and nitrogen, etc. were weakly related or unrelated to the relative abundance of resistance genes. Based on our results we conclude that there is neither considerable enrichment nor purification of antibiotic resistance genes in studied conventional WWTPs.

  8. Pharmacodynamics of beta-lactam antibiotics. Studies on the paradoxical and postantibiotic effects in vitro and in an animal model.

    Science.gov (United States)

    Odenholt-Tornqvist, I

    1989-01-01

    The pharmacodynamics of antibiotics, i.e. the rate of killing and the time before regrowth of surviving bacteria, may be important factors for determination of the dosage interval. In the present study the effect of protein binding, antibiotic concentrations, bacterial growth phase and bacterial inoculum on the rate of bacterial killing was investigated. The postantibiotic effect (PAE) was also studied in vitro and in vivo. The killing rate of S. aureus did not differ when the bacteria were exposed to the same free concentrations of dicloxacillin in medium with and without albumin. Protein binding per se did thus not diminish the bactericidal activity. A paradoxically reduced bactericidal effect was noted when S. aureus was exposed to high concentrations of dicloxacillin, cloxacillin and benzylpenicillin. For determination of PAE of imipenem on Ps. aeruginosa, counts of viable bacteria were compared with assay of bacterial intracellular ATP. Both methods demonstrated a PAE for the strains tested at an inoculum of 10(6) cfu/ml. At an inoculum of 10(8) cfu/ml no PAE was found, which coincided with a lack of bactericidal effect. Both the PAE and the bactericidal effect were restored with aeration of the cultures, indicating insufficient penetration of imipenem to the target sites at low oxygen tension. An in vivo model in rabbits with implanted tissue cages was developed for evaluation of the PAE. Group A beta-hemolytic streptococci showed a PAE of approximately 2 h in vivo, which correlated well with the PAE found in vitro. Despite that streptococci in postantibiotic phase (PA-phase) were non-multiplying, such bacteria were killed as efficiently as previously untreated controls when exposed to 10xMIC of penicillin both in vitro and in vivo. However, streptococci in PA-phase were much more sensitive to the repeated challenge to subinhibitory concentrations of penicillin than previously untreated controls. In vivo, no difference in sensitivity to sub-MIC penicillin

  9. High beta-Lactamase Levels Change the Pharmacodynamics of beta-Lactam Antibiotics in Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Wang, Hengzhuang; Ciofu, Oana; Yang, Liang

    2013-01-01

    the role of beta-lactamase in the pharmacokinetics (PK) and pharmacodynamics (PD) of ceftazidime and imipenem on P. aeruginosa biofilms. P. aeruginosa PAO1 and its corresponding beta-lactamase-overproducing mutant, PA Delta DDh2Dh3, were used in this study. Biofilms of these two strains in flow chambers......, microtiter plates, and on alginate beads were treated with different concentrations of ceftazidime and imipenem. The kinetics of antibiotics on the biofilms was investigated in vitro by time-kill methods. Time-dependent killing of ceftazidime was observed in PAO1 biofilms, but concentration-dependent killing...... activity of ceftazidime was observed for beta-lactamase-overproducing biofilms of P. aeruginosa in all three models. Ceftazidime showed time-dependent killing on planktonic PAO1 and PA Delta DDh2Dh3. This difference is probably due to the special distribution and accumulation in the biofilm matrix of beta...

  10. In vitro activities of beta-lactam antibiotics alone and in combination with sulbactam against Gram-negative bacteria.

    Science.gov (United States)

    Wang, Fu-Der; Lin, Mei-Lin; Lee, Wen-Sen; Liu, Cheng-Yi

    2004-06-01

    The resistance rates of ampicillin/sulbactam 2:1 against imipenem-susceptible and -resistant Acinetobacter baumannii were 23.5 and 30%, respectively. Ceftazidime/sulbactam combination showed significant reduction of resistant rates against Enterobacter cloacae, A. baumannii, ESBL Klebsiella pneumoniae. MIC90 of cefoperazone against E. cloacae, Serratia marcescens, A. baumannii and ESBL K. pneumoniae were > 128 mg/l. Addition of sulbactam enhanced the antimicrobial activities significantly. When imipenem was combined with sulbactam, the resistant rates against imipenem-resistant A. baumanni were significantly reduced. Cefepime/sulbactam combination was active against imipenem-resistant A. baumanni. The resistance rates of aztreonam/sulbactam combination against E. cloacae, imipenem-sensitive and resistant A. baumannii, ESBL K. pneumoniae were lowered significantly. The cefotaxime/sulbactam combination showed a significant improvement of activities against E. cloacae, S. marcescens, A. baumannii and ESBL K. pneumoniae. Copyright 2004 Elsevier B.V.

  11. Penicillin and beta-lactam allergy: epidemiology and diagnosis.

    Science.gov (United States)

    Macy, Eric

    2014-11-01

    Penicillin is the most common beta-lactam antibiotic allergy and the most common drug class allergy, reported in about 8% of individuals using health care in the USA. Only about 1% of individuals using health care in the USA have a cephalosporin allergy noted in their medical record, and other specific non-penicillin, non-cephalosporin beta-lactam allergies are even rarer. Most reported penicillin allergy is not associated with clinically significant IgE-mediated reactions after penicillin rechallenge. Un-verified penicillin allergy is a significant and growing public health problem. Clinically significant IgE-mediated penicillin allergy can be safely confirmed or refuted using skin testing with penicilloyl-poly-lysine and native penicillin G and, if skin test is negative, an oral amoxicillin challenge. Acute tolerance of an oral therapeutic dose of a penicillin class antibiotic is the current gold standard test for a lack of clinically significant IgE-mediated penicillin allergy. Cephalosporins and other non-penicillin beta-lactams are widely, safely, and appropriately used in individuals, even with confirmed penicillin allergy. There is little, if any, clinically significant immunologic cross-reactivity between penicillins and other beta-lactams. Routine cephalosporin skin testing should be restricted to research settings. It is rarely needed clinically to safely manage patients and has unclear predictive value at this time. The use of alternative cephalosporins, with different side chains, is acceptable in the setting of a specific cephalosporin allergy. Carbapenems and monobactams are also safely used in individuals with confirmed penicillin allergy. A certain predictable, but low, rate of adverse reactions will occur with all beta-lactam antibiotic use both pre- and post-beta-lactam allergy evaluations.

  12. Validation of the BetaStar® Advanced for Beta-lactams Test Kit for the Screening of Bulk Tank and Tanker Truck Milks for the Presence of Beta-lactam Drug Residues.

    Science.gov (United States)

    Denhartigh, Andrew; Reynolds, Lindsay; Palmer, Katherine; Klein, Frank; Rice, Jennifer; Rejman, John J

    2018-05-18

    A validation study was conducted for an immunochromatographic method (BetaStar ® Advanced for Beta-lactams) for the detection of beta-lactam residues in raw, commingled bovine milk. The assay detected amoxicillin, ampicillin, cloxacillin, penicillin, cephapirin, and ceftiofur below the U.S. Food and Drug Administration tolerance levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. The results of internal and independent laboratory dose-response studies employing spiked samples were in agreement. The test detected all six drugs at the approximate 90/95% sensitivity levels in milk from cows treated with each drug. Selectivity of the assay was 100%, as no false-positive results were obtained in testing 1148 control milk samples. Testing the estimated 90/95% sensitivity level for amoxicillin (8.5 ppb), ampicillin (6.9 ppb), cloxacillin (8.9 ppb), penicillin (4.2 ppb), and cephapirin (17.6 ppb), and at 100 ppb for each antibiotic, resulted in 94-100% positive tests for each of the beta-lactam drugs. The results of ruggedness experiments established the operating parameter tolerances for the assay. Cross-reactivity testing established that the assay detects other certain beta-lactam drugs, but it does not cross-react with any of 30 drugs belonging to seven different drug classes. Abnormally high bacterial or somatic cell counts in raw milk produced no assay interference.

  13. Is the addition of aminoglycosides to beta-lactams in cancer patients with febrile neutropenia needed?

    Science.gov (United States)

    Contreras, Valeria; Sepúlveda, Sebastián; Heredia, Ana

    2016-02-24

    It is still controversial if the combined use of beta-lactam antibiotics and aminoglycosides has advantages over broad-spectrum beta-lactam monotherapy for the empirical treatment of cancer patients with febrile neutropenia. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified three systematic reviews including 14 pertinent randomized trials. We combined the evidence using meta-analysis and generated a summary of findings table following the GRADE approach. We concluded the combination of beta-lactam antibiotics and aminoglycosides probably does not lead to a reduced mortality in febrile neutropenic cancer patients and it might increase nephrotoxicity.

  14. Looking for the new preparations for antibacterial therapy. II. Clinical trials; new beta-lactam antibiotics and beta-lactamase inhibitors.

    Science.gov (United States)

    Karpiuk, Izabela; Tyski, Stefan

    2013-01-01

    To obtain a status of a medicinal product, a compound possessing potential antimicrobial activity and displaying no cytotoxicity, must undergo three phases of clinical trials to prove its therapeutic efficacy, safety and quality. Properties of the compound should be based on the results of studies meeting specific criteria. Studies should be: randomized, double-blind, involving sufficient number of volunteers, concerning the infections localized in strictly defined area and caused by identified microorganisms. After the medicinal product is authorized to be on the market, clinical trials of the fourth phase are carried out to detect adverse effects, overdose symptoms, interactions of the new drug with other medicinal products and to establish characteristic of activity among groups such as children, elderly, women in pregnancy and patients suffering from other diseases, but only if the benefits of receiving treatment outweigh the risks. This article is a second part of the series associated with searching for new antibacterial agents and it relates to performance of clinical trials and the new compounds belonging to the class of beta-lactams. Among the 9 presented compounds, candidates to become medicinal products, two belong to the cephalosporins (CXA-101, S-649266), one to carbapenems (razupenem), three to monobactams (BAL30072, BAL30376, MC-1) and three to beta-lactamase inhibitors (NXL-104, MK-7655, ME1071).

  15. Efflux pump, the masked side of beta-lactam resistance in Klebsiella pneumoniae clinical isolates.

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    Jean-Marie Pages

    Full Text Available BACKGROUND: Beta-lactamase production and porin decrease are the well-recognized mechanisms of acquired beta-lactam resistance in Klebsiella pneumoniae isolates. However, such mechanisms proved to be absent in K. pneumoniae isolates that are non susceptible to cefoxitin (FOX and susceptible to amoxicillin+clavulanic acid in our hospital. Assessing the role of efflux pumps in this beta-lactam phenotype was the aim of this study. METHODOLOGY/FINDINGS: MICs of 9 beta-lactams, including cloxacillin (CLX, and other antibiotic families were tested alone and with an efflux pump inhibitor (EPI, then with both CLX (subinhibitory concentrations and EPI against 11 unique bacteremia K. pneumoniae isolates displaying the unusual phenotype, and 2 ATCC strains. CLX and EPI-dose dependent effects were studied on 4 representatives strains. CLX MICs significantly decreased when tested with EPI. A similar phenomenon was observed with piperacillin+tazobactam whereas MICs of the other beta-lactams significantly decreased only in the presence of both EPI and CLX. Thus, FOX MICs decreased 128 fold in the K. pneumoniae isolates but also 16 fold in ATCC strain. Restoration of FOX activity was CLX dose-dependent suggesting a competitive relationship between CLX and the other beta-lactams with regard to their efflux. For chloramphenicol, erythromycin and nalidixic acid whose resistance was also due to efflux, adding CLX to EPI did not increase their activity suggesting differences between the efflux process of these molecules and that of beta-lactams. CONCLUSION: This is the first study demonstrating that efflux mechanism plays a key role in the beta-lactam susceptibility of clinical isolates of K. pneumoniae. Such data clearly evidence that the involvement of efflux pumps in beta-lactam resistance is specially underestimated in clinical isolates.

  16. Dual beta-lactam therapy for serious Gram-negative infections: is it time to revisit?

    Science.gov (United States)

    Rahme, Christine; Butterfield, Jill M; Nicasio, Anthony M; Lodise, Thomas P

    2014-12-01

    We are rapidly approaching a crisis in antibiotic resistance, particularly among Gram-negative pathogens. This, coupled with the slow development of novel antimicrobial agents, underscores the exigency of redeploying existing antimicrobial agents in innovative ways. One therapeutic approach that was heavily studied in the 1980s but abandoned over time is dual beta-lactam therapy. This article reviews the evidence for combination beta-lactam therapy. Overall, in vitro, animal and clinical data are positive and suggest that beta-lactam combinations produce a synergistic effect against Gram-negative pathogens that rivals that of beta-lactam-aminoglycoside or beta-lactam-fluoroquinolone combination therapy. Although the precise mechanism of improved activity is not completely understood, it is likely attributable to an enhanced affinity to the diverse penicillin-binding proteins found among Gram negatives. The collective data indicate that dual beta-lactam therapy should be revisited for serious Gram-negative infections, especially in light of the near availability of potent beta-lactamase inhibitors, which neutralize the effect of problematic beta-lactamases. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Antimicrobial activity of beta-lactams against multiresistant micro-organisms from the family Enterobacteriaceae, and genus Pseudomonas.

    Science.gov (United States)

    Niebla, A; González, I; Vallín, C

    1994-01-01

    The antimicrobial activity of twenty beta-lactams was determined against multiresistant micro-organisms from the Enterobacteriaceae family (450) and the genus Pseudomonas (90). The antimicrobial susceptibility was assessed by the disk diffusion method. The most effective antibiotics were cephalosporins of the second and third generation, and non-classical beta-lactams (imipenem and moxalactam). A pronounced resistance was found to carbenicillin, ampicillin, cephalotin and cefazolin. These resistance patterns corresponded to a high consumption of these antibiotics.

  18. Resistance patterns to beta-lactams and quinolones in clinical isolates of bacteria from Cuban hospitals.

    Science.gov (United States)

    Gonzáles, I; Niebla, A; Vallin, C

    1995-01-01

    The resistance patterns to 26 beta-lactams and 8 quinolones of clinical isolates from Cuban hospitals were evaluated using the disk susceptibility test, according to the NCCLS guidelines (1992). The genera studied were Escherichia sp (320), Enterobacter sp (10), Klebsiella sp (90), Proteus sp (10), Pseudomonas sp (90), Serratia sp (20), and Staphylococcus sp (80). Higher resistance to beta-lactams was observed in the genera Pseudomonas, Escherichia and Klebsiella. For fluoroquinolones we found no significant resistance, with the exception of the genus Klebsiella. The most effective antibiotics were cephalosporins of the second and third generations, fluoroquinolones, and non-classical beta-lactams (cephamycins, moxalactam and monobactams). On the contrary, a pronounced resistance was found to penicillin, oxacillin, ticarcillin, ampicillin, methicillin, nalidixic acid and cinoxacin. These resistance patterns correspond to the high consumption of these antibiotics throughout the country.

  19. Abundances of tetracycline, sulphonamide and beta-lactam antibiotic resistance genes in conventional wastewater treatment plants (WWTPs) with different waste load

    DEFF Research Database (Denmark)

    Laht, Mailis; Karkman, Antti; Voolaid, Veiko

    2014-01-01

    Antibiotics and antibiotic resistant bacteria enter wastewater treatment plants (WWTPs), an environment where resistance genes can potentially spread and exchange between microbes. Several antibiotic resistance genes (ARGs) were quantified using qPCR in three WWTPs of decreasing capacity located...... abundances with 16S rRNA gene abundances while assessing if the respective genes increased or decreased during treatment. ARGs were detected in most samples; sul1, sul2, and tetM were detected in all samples. Statistically significant differences (adjusted p... in the relative abundance of resistance genes, while the raw abundances fell by several orders of magnitude. Standard water quality variables (biological oxygen demand, total phosphorus and nitrogen, etc.) were weakly related or unrelated to the relative abundance of resistance genes. Based on our results we...

  20. [Influence of testing conditions on the susceptibility results of Staphylococcus cohnii to beta-lactams].

    Science.gov (United States)

    Nowak, Tonmasz; Szewczyk, Eligia M

    2006-01-01

    The high occurence of coagulase-negative staphylococci among bacteria responsible for hospital infections is unquestioned. Studies on the poorly-known novobiocin-resistant, coagulase-negative Staphylococcus cohnii were undertaken. The possibilities of optimizing conditions for determination of susceptibility to beta-lactam antibiotics of this species were researched. In the case of S. cohnii the new cefoxitin test for detection of methicillin resistant strains, introduced by the National Reference Centre for Antibiotics in Poland was found as a good and of credible quality. It was also shown, that application in in vitro examination conditions stimulating the mechanisms of resistance to beta-lactam antibiotics, supplies credible results relating to their true susceptibility. The necessity of establishing individual conditions for susceptibility determination in different species of coagulase-negative staphylococci was suggested.

  1. Prognostic criteria of sensitivity to antibiotics of staphylococcus clinical strains

    Directory of Open Access Journals (Sweden)

    Gordiy Paliy

    2015-06-01

    Department of Microbiology, Virology and Immunology, Vinnytsya National Pirogov Memorial Medical University Ministry of Health of Ukraine   Abstract In the article, the new data of sensitivity to antibiotics in clinical strains of Staphylococci are presented. For the first time, analytic dependence of dynamic prognostic criteria of the change of sensitivity of S. aureus clinical strains, isolated from patients, was obtained by means of mathematical prediction. There were investigated prognosticated indexes of Staphylococcus strains’ sensitivity to beta-lactams (oxacillin, ceftriaxone, imipenem and meropenem, vancomycin and linezolid. The dynamic of sensitivity decreasing to oxacillin, ceftriaxone, carbapenems (imipenem, meropenem, vancomycin (92,5 % and high sensitivity to linezolid in clinical strains of S. aureus were found out. Key words: sensitivity, antibiotics, Staphylococcus, prognostic indexes.

  2. Risk of surgical site infection, acute kidney injury, and Clostridium difficile infection following antibiotic prophylaxis with vancomycin plus a beta-lactam versus either drug alone: A national propensity-score-adjusted retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Westyn Branch-Elliman

    2017-07-01

    Full Text Available The optimal regimen for perioperative antimicrobial prophylaxis is controversial. Use of combination prophylaxis with a beta-lactam plus vancomycin is increasing; however, the relative risks and benefits associated with this strategy are unknown. Thus, we sought to compare postoperative outcomes following administration of 2 antimicrobials versus a single agent for the prevention of surgical site infections (SSIs. Potential harms associated with combination regimens, including acute kidney injury (AKI and Clostridium difficile infection (CDI, were also considered.Using a multicenter, national Veterans Affairs (VA cohort, all patients who underwent cardiac, orthopedic joint replacement, vascular, colorectal, and hysterectomy procedures during the period from 1 October 2008 to 30 September 2013 and who received planned manual review of perioperative antimicrobial prophylaxis regimen and manual review for the 30-day incidence of SSI were included. Using a propensity-adjusted log-binomial regression model stratified by type of surgical procedure, the association between receipt of 2 antimicrobials (vancomycin plus a beta-lactam versus either single agent alone (vancomycin or a beta-lactam and SSI was evaluated. Measures of association were adjusted for age, diabetes, smoking, American Society of Anesthesiologists score, preoperative methicillin-resistant Staphylococcus aureus (MRSA status, and receipt of mupirocin. The 7-day incidence of postoperative AKI and 90-day incidence of CDI were also measured. In all, 70,101 procedures (52,504 beta-lactam only, 5,089 vancomycin only, and 12,508 combination with 2,466 (3.5% SSIs from 109 medical centers were included. Among cardiac surgery patients, combination prophylaxis was associated with a lower incidence of SSI (66/6,953, 0.95% than single-agent prophylaxis (190/12,834, 1.48%; crude risk ratio [RR] 0.64, 95% CI 0.49, 0.85; adjusted RR 0.61, 95% CI 0.46, 0.83. After adjusting for SSI risk, no

  3. Risk of surgical site infection, acute kidney injury, and Clostridium difficile infection following antibiotic prophylaxis with vancomycin plus a beta-lactam versus either drug alone: A national propensity-score-adjusted retrospective cohort study.

    Science.gov (United States)

    Branch-Elliman, Westyn; Ripollone, John E; O'Brien, William J; Itani, Kamal M F; Schweizer, Marin L; Perencevich, Eli; Strymish, Judith; Gupta, Kalpana

    2017-07-01

    The optimal regimen for perioperative antimicrobial prophylaxis is controversial. Use of combination prophylaxis with a beta-lactam plus vancomycin is increasing; however, the relative risks and benefits associated with this strategy are unknown. Thus, we sought to compare postoperative outcomes following administration of 2 antimicrobials versus a single agent for the prevention of surgical site infections (SSIs). Potential harms associated with combination regimens, including acute kidney injury (AKI) and Clostridium difficile infection (CDI), were also considered. Using a multicenter, national Veterans Affairs (VA) cohort, all patients who underwent cardiac, orthopedic joint replacement, vascular, colorectal, and hysterectomy procedures during the period from 1 October 2008 to 30 September 2013 and who received planned manual review of perioperative antimicrobial prophylaxis regimen and manual review for the 30-day incidence of SSI were included. Using a propensity-adjusted log-binomial regression model stratified by type of surgical procedure, the association between receipt of 2 antimicrobials (vancomycin plus a beta-lactam) versus either single agent alone (vancomycin or a beta-lactam) and SSI was evaluated. Measures of association were adjusted for age, diabetes, smoking, American Society of Anesthesiologists score, preoperative methicillin-resistant Staphylococcus aureus (MRSA) status, and receipt of mupirocin. The 7-day incidence of postoperative AKI and 90-day incidence of CDI were also measured. In all, 70,101 procedures (52,504 beta-lactam only, 5,089 vancomycin only, and 12,508 combination) with 2,466 (3.5%) SSIs from 109 medical centers were included. Among cardiac surgery patients, combination prophylaxis was associated with a lower incidence of SSI (66/6,953, 0.95%) than single-agent prophylaxis (190/12,834, 1.48%; crude risk ratio [RR] 0.64, 95% CI 0.49, 0.85; adjusted RR 0.61, 95% CI 0.46, 0.83). After adjusting for SSI risk, no association

  4. Type 1 Ig-E mediated allergy to human insulin, insulin analogues and beta-lactam antibiotics Hipersensibilidade imediata a insulina humana, análogos de insulina e a antibióticos beta-lactâmicos

    Directory of Open Access Journals (Sweden)

    Pedro Andrade

    2012-12-01

    Full Text Available Insulin, a crucial therapeutic agent for diabetes mellitus, has been rarely associated with hypersensitivity events. We present a 69-year-old type-2 diabetic patient with urticariform lesions on the sites of subcutaneous injection of insulin. The patient denied any known allergies, except for an unspecific cutaneous reaction after intramuscular penicillin administration in childhood. Prick tests revealed positive reactions to all tested human insulins and insulin analogues. Serum IgE levels were above normal range and RAST tests were positive for human, bovine and porcine insulins, as well as beta-lactams. Type 1 IgEmediated allergy to insulin analogues demands a prompt diagnosis and represents a significant therapeutic challenge in diabetic patients.A insulina é um agente indispensável para o controlo da diabetes mellitus. Os efeitos adversos da sua administração, em particular fenómenos de hipersensibilidade, são raros. Apresentamos um doente de 69 anos, diabético do tipo 2, com episódios recorrentes de lesões urticariformes nos locais de administração subcutânea de insulina. Negava alergias medicamentosas, à excepção de reacção não especificada na infância após penicilina intramuscular. Foram realizados testes cutâneos por puntura (prick tests com diversos tipos de insulina humana e análogos, todos com reacções positivas, associando elevação dos níveis de IgE sérica e provas RAST positivas para as insulinas humana, bovina e porcina e para os antibióticos beta-lactâmicos. A alergia a análogos de insulina exige um diagnóstico precoce, originando um desafio terapêutico importante no doente diabético.

  5. Activity of beta-lactam beta-lactamase inhibitor combinations against extended spectrum beta-lactamase producing enterobacteriaceae in urinary isolates

    International Nuclear Information System (INIS)

    Iqbal, F.I.; Farooqi, B.J.

    2012-01-01

    Objective: To determine the susceptibility pattern of beta-lactam beta-lactamase inhibitor combinations against extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae in urinary isolates. Study Design: Observational study. Place and Duration of Study: Ziauddin University Hospital, Karachi, from February to October 2008. Methodology: A total of 190 consecutive non-duplicate isolates of ESBL producing Enterobacteriaceae from urine samples of in-patients were included in the study. Urinary samples from out-patients, repeat samples and non-ESBL producing isolates were excluded. Detection of ESBL was carried out by double disk diffusion technique. Antimicrobial susceptibility testing was performed using modified Kirby Bauer's disk diffusion method according to CLSI guidelines. Statistical analysis was performed by SPSS version 10. Results: Of the 190 ESBL isolates tested, 88 cases (46.31%) were sensitive and 6 cases (3.15%) were resistant to all three combinations, the rest 96 cases (50.52%) were resistant to at least one of the combinations. Susceptibility pattern of cefoperazone/sulbactam, piperacillin/tazobactam, and amoxicillin/clavulanic acid was 95.26, 92.10, and 44.31 percent respectively. Conclusion: Cefoperazone/sulbactam exhibited the best activity against ESBL producing Enterobacteriaceae followed by piperacillin/tazobactam. Hospital antibiotic policies should be reviewed periodically to reduce the usage of extended spectrum cephalosporins and replace them with beta-lactam beta-lactamase inhibitor combinations agent for treating urinary tract infections. (author)

  6. Beta-lactam combination therapy for the treatment of Staphylococcus aureus and Enterococcus species bacteremia: A summary and appraisal of the evidence

    Directory of Open Access Journals (Sweden)

    Rachel Bartash

    2017-10-01

    Full Text Available Staphylococcal bacteremia and enterococcal bacteremia are prevalent in hospitalized or recently instrumented patients, and are associated with significant morbidity and mortality. They are often difficult to treat due to the pathogenicity of the organisms, poor response to antibiotics, and increasing development of multidrug resistance. Therefore, there has been increasing interest in combination therapy for the treatment of these infections. The aim of this review was to summarize and assess the evidence supporting combination beta-lactam therapy for both Staphylococcus aureus and Enterococcus species blood stream infections. Currently, there is promising in vitro data but little clinical evidence supporting combination beta-lactam therapy for this indication. Further clinical investigations are needed to elucidate the potential benefits of beta-lactam combination therapy over monotherapy for Gram-positive bacteremia, although combination therapy may be useful in refractory cases of bacteremia that do not respond to standard antibiotic therapy.

  7. Mechanism of activity, biosynthesis and identification of beta-lactam antimicrobial drugs

    Directory of Open Access Journals (Sweden)

    Marija Sedak

    2011-01-01

    Full Text Available Antimicrobal drugs are chemotherapeutics with a wide spectrum of use in human and veterinary medicine and livestock practice. Beta-lactams are the most widespread group of antimicrobal drugs and are most often used in human and veterinary medicine in the treatment of bacterial infections due to their powerful antimicrobial activity and very low toxicity. They are divided into the groups of penicillins, cefalosporins and monobactams. Penicillins are obtained from the filtrate of the mould cultures Penicillium notatum and Penicillium chrysogenum, while cefalosporins are obtained from the filtrate of the actinomycete cultures (Cephalosporium acremonium. Research has lead to the discovery of active groups of 6-amino-penicillin acids, whose isolation has made it possible to produce semi-synthetic penicillins that have surpassed the limitations of natural penicillin G. The physico-chemical properties of the beta-lactams can be altered by substituting hydrogen in the carboxyl group of penicillins, i.e. in modifying the side chain of cefalosporin. This increases the resistance to the activity of β-lactamase and expands the spectrum of activity. Beta-lactams, in therapy concentrations, act as a bacteriocide by inhibiting the synthesis of bacterial cell walls. Penicillins are important for antibacterial chemotherapy, often in combination with other antimicrobal drugs. Cefalosporins are usually used as a replacement for penicillin in treating infections caused by gram-negative bacteria and in prophylaxis for surgery. The use of beta-lactams in animals used for food can result in the residues of these drugs in meat and meat products or milk and eggs. The introduction of antimicrobal drugs in the human body via food is particularly dangerous due to their direct toxicity or carcinogenicity, influences on the composition of the intestinal microflora, possible allergic reactions in sensitive people, and the appearance of resistance of individual pathogenic

  8. Cross-class resistance to non-beta-lactam antimicrobials in extended-spectrum beta-lactamase-producing Klebsiella pneumoniae.

    Science.gov (United States)

    Procop, Gary W; Tuohy, Marion J; Wilson, Deborah A; Williams, Delisa; Hadziyannis, Emilia; Hall, Gerri S

    2003-08-01

    Extended spectrum beta-lactamases are modified beta-lactamase enzymes that impart resistance to third-generation cephalosporins and make all beta-lactam antibiotics and cephalosporins useless for therapy. We compared the antimicrobial susceptibility profiles of extended-spectrum beta-lactamase (ESBL)-producing and non-ESBL-producing isolates of Klebsiella pneumoniae. The ESBL producers had significantly diminished susceptibility compared with the non-ESBL producers for gentamicin (P < .001), tobramycin (P < .001), amikacin (P < .005), trimethoprim-sulfamethoxazole (P < .01), ciprofloxacin (P < .001), and nitrofurantoin (P < .001). All isolates were susceptible to imipenem. ESBL-producing K pneumoniae may also be resistant to non-beta-lactam antibiotics. Therefore, susceptibility testing of these isolates is critical for guiding therapy.

  9. Penicillin and Beta-Lactam Hypersensitivity.

    Science.gov (United States)

    Har, Daniel; Solensky, Roland

    2017-11-01

    Ten percent of patients report penicillin allergy, but more than 90% of these individuals can tolerate penicillins. Skin testing remains the optimal method for evaluation of possible IgE-mediated penicillin allergy and is recommended by professional societies, as the harms for alternative antibiotics include antimicrobial resistance, prolonged hospitalizations, readmissions, and increased costs. Removal of penicillin allergy leads to decreased utilization of broad-spectrum antibiotics, such as fluoroquinolones and vancomycin. There is minimal allergic cross-reactivity between penicillins and cephalosporins. IgE-mediated allergy to cephalosporins is usually side-chain specific and may warrant graded challenge with cephalosporins containing dissimilar R1 or R2 group side chains. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. "Click" saccharide/beta-lactam hybrids for lectin inhibition.

    Science.gov (United States)

    Palomo, Claudio; Aizpurua, Jesus M; Balentová, Eva; Azcune, Itxaso; Santos, J Ignacio; Jiménez-Barbero, Jesús; Cañada, Javier; Miranda, José Ignacio

    2008-06-05

    Hybrid glycopeptide beta-lactam mimetics designed to bind lectins or carbohydrate recognition domains in selectins have been prepared according to a "shape-modulating linker" design. This approach was implemented using the azide-alkyne "click" cycloaddition reaction, and as shown by NMR/MD experiments, binding of the resulting mimetics to Ulex Europaeus Lectin-1 (UEL-1) occurred after a "bent-to-extended" conformational change around a partially rotatable triazolylmethylene moiety.

  11. Resistencia a antibióticos no betalactámicos de aislamientos invasores de Streptococcus pneumoniae en niños latinoamericanos: SIREVA II, 2000-2005 Resistance to non-beta-lactam antibiotics in the clinical isolates of Streptococcus pneumoniae of children in Latin America: SIREVA II, 2000-2005

    Directory of Open Access Journals (Sweden)

    Clara Inés Agudelo

    2009-04-01

    susceptibility was determined through the methods established and standardized by the SIREVA project. Multidrug resistance was defined as: resistance to three or more antibiotics of the same class; to the non-beta-lactams analyzed by this study; or, to the beta-lactams evaluated by a previous study, in which 37.8% of these isolates showed decreased susceptibility to penicillin. RESULTS:Some degree of resistance was found to TMP-SMZ and erythromycin (56.4% and 15.4% of the isolates studied, respectively, with 4.6% highly resistant to chloramphenicol. All isolates were susceptible to vancomycin. The highest prevalence of TMP-SMZ resistance was observed in the pneumonia isolates; and that of erythromycin, in cases of sepsis (61.6% and 25.5%, respectively; P < 0.01. The high-est prevalence of TMP-SMZ resistance was found in Brazil (71.9%, and that of erythromycin, in Mexico (38.2% and Venezuela (32.9%. The 14, 6B, 19F, and 23F serotypes were most often associated with resistance to the antibiotics in the study. CONCLUSIONS: High and increasing rates of isolates resistant to TMP-SMZ and erythromycin were observed, as well as a decreasing percentage of isolates resistant to chloramphenicol. These trends highlight differences among the countries studied.

  12. The order of administration of macrolides and beta-lactams may impact the outcomes of hospitalized patients with community-acquired pneumonia: results from the community-acquired pneumonia organization.

    Science.gov (United States)

    Peyrani, Paula; Wiemken, Timothy L; Metersky, Mark L; Arnold, Forest W; Mattingly, William A; Feldman, Charles; Cavallazzi, Rodrigo; Fernandez-Botran, Rafael; Bordon, Jose; Ramirez, Julio A

    2018-01-01

    The beneficial effect of macrolides for the treatment of community-acquired pneumonia (CAP) in combination with beta-lactams may be due to their anti-inflammatory activity. In patients with pneumococcal meningitis, the use of steroids improves outcomes only if they are administered before beta-lactams. The objective of this study was to compare outcomes in hospitalized patients with CAP when macrolides were administered before, simultaneously with, or after beta-lactams. Secondary data analysis of the Community-Acquired Pneumonia Organization (CAPO) International Cohort Study database. Study groups were defined based on the sequence of administration of macrolides and beta-lactams. The study outcomes were time to clinical stability (TCS), length of stay (LOS) and in-hospital mortality. Accelerated failure time models were used to evaluate the adjusted impact of sequential antibiotic administration and time-to-event outcomes, while a logistic regression model was used to evaluate their adjusted impact on mortality. A total of 99 patients were included in the macrolide before group and 305 in the macrolide after group. Administration of a macrolide before a beta-lactam compared to after a beta-lactam reduced TCS (3 vs. 4 days, p = .011), LOS (6 vs. 7 days, p = .002) and mortality (3 vs. 7.2%, p = .228). The administration of macrolides before beta-lactams was associated with a statistically significant decrease in TCS and LOS and a non-statistically significant decrease in mortality. The beneficial effect of macrolides in hospitalized patient with CAP may occur only if administered before beta-lactams.

  13. Antibiotic sensitivity and resistance in Ornithobacterium rhinotracheale strains from Belgian broiler chickens.

    Science.gov (United States)

    Devriese, L A; De Herdt, P; Haesebrouck, F

    2001-06-01

    Establishing the antibiotic sensitivity of the avian respiratory pathogen Ornithobacterium rhinotracheale is difficult because of the organism's complex growth requirements and the unusually frequent occurrence of resistance. The minimal inhibitory concentrations of 10 antibiotics were determined for 45 strains of O. rhinotracheale from Belgian broiler chickens collected from 45 farms between 1995 and 1998. They were compared with the type strain, which was isolated from a turkey, and a strain isolated from a rook. All the broiler strains were resistant to lincomycin and to the beta-lactams ampicillin and ceftiofur. Less than 10% of the strains were sensitive to the macrolides tylosin and spiramycin, tilmicosin and flumequine. A few strains were sensitive to enrofloxacin and doxycycline. All strains were sensitive to tiamulin.

  14. Susceptibility of Eikenella corrodens to Newer Beta-Lactam Antibiotics

    OpenAIRE

    1981-01-01

    In vitro susceptibility testing of 28 strains of Eikenella corrodens by the agar dilution technique showed that all strains were uniformly susceptible to penicillin, ticarcillin, cefoxitin, cefotaxime, N-formimidoyl thienamycin, and moxalactam and resistant to clindamycin and cefadroxil. Cefoperazone, piperacillin, and mezlocillin showed good activity, with some strains relatively resistant. Bacampicillin and cefamandole showed relatively poor activity.

  15. Beta-lactam resistance in the gram negatives: increasing complexity of conditional, composite and multiply resistant phenotypes.

    Science.gov (United States)

    Iredell, Jon; Thomas, Lee; Espedido, Björn

    2006-12-01

    The greatest impact of microbiology data on clinical care is in the critically ill. Unfortunately, this is also the area in which microbiology laboratories are most often non-contributive. Attempts to move to rapid, culture-independent diagnostics are driven by the need to expedite urgent results. This is difficult in Gram-negative infection because of the complexity of the antibiotic resistance phenotype. Here, we discuss resistance to modern beta-lactams as a case in point. Recent outbreaks of transmissible carbapenem resistance among Gram-negative enteric pathogens in Sydney and Melbourne serve to illustrate the pitfalls of traditional phenotypical approaches. A better understanding of the epidemiology and mosaic nature of antibiotic resistance elements in the microflora is needed for us to move forward.

  16. NADPH-dependent glutamate dehydrogenase in Penicillium chrysogenum is involved in regulation of beta-lactam production

    DEFF Research Database (Denmark)

    Thykær, Jette; Kildegaard, Kanchana Rueksomtawin; Noorman, H.

    2008-01-01

    was detected in either of the Delta gdhA strains. Supplementation with glutamate restored growth but no beta-lactam production was detected for the constructed strains. Cultures with high ammonium concentrations (repressing conditions) and with proline as nitrogen source (de-repressed conditions) showed......The interactions between the ammonium assimilatory pathways and beta-lactam production were investigated by disruption of the NADPH-dependent glutamate dehydrogenase gene (gdhA) in two industrial beta-lactam-producing strains of Penicillium chrysogenum. The strains used were an adipoyl-7-ADCA...... continued beta-lactam production for the reference strains whereas the Delta gdhA strains remained non-productive under all conditions. By overexpressing the NAD-dependent glutamate dehydrogenase, the specific growth rate could be restored, but still no beta-lactam production was detected. The results...

  17. Point-of-care Beta-lactam Allergy Skin Testing by Antimicrobial Stewardship Programs: A Pragmatic Multicenter Prospective Evaluation.

    Science.gov (United States)

    Leis, Jerome A; Palmay, Lesley; Ho, Grace; Raybardhan, Sumit; Gill, Suzanne; Kan, Tiffany; Campbell, Jackie; Kiss, Alex; McCready, Janine B; Das, Pavani; Minnema, Brian; Powis, Jeff E; Walker, Sandra A N; Ferguson, Heather; Wong, Benny; Weber, Elizabeth

    2017-06-01

    Beta-lactam allergy skin testing (BLAST) is recommended by antimicrobial stewardship program (ASP) guidelines, yet few studies have systematically evaluated its impact when delivered at point-of-care. We conducted a pragmatic multicenter prospective evaluation of the use of point-of-care BLAST by ASPs. In staggered 3-month intervals, ASP teams at three hospitals received training by allergists to offer BLAST for eligible patients with infectious diseases receiving non-preferred beta-lactam therapy due to severity of their allergy. The primary outcome was the proportion of patients receiving the preferred beta-lactam therapy. Of 827 patients with reported beta-lactam allergy over 15-months, beta-lactam therapy was preferred among 632(76%). During baseline periods, 50% (124/246) received preferred beta-lactam therapy based on history, compared with 60% (232/386) during the intervention periods (p=0.02), which improved further to 81% (313/386) upon provision of BLAST (pcare across three hospital ASPs resulted in greater use of preferred beta-lactam therapy without increasing the risk of adverse drug reactions. Longer term studies are needed to better assess the safety and clinical impact of this ASP intervention. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  18. [Antimicrobial activity of fosfomycin under various conditions against standard strains, beta-lactam resistant strains, and multidrug efflux system mutants].

    Science.gov (United States)

    Mikuniya, Takeshi; Hiraishi, Toru; Maebashi, Kazunori; Ida, Takashi; Takata, Toshihiko; Hikida, Muneo; Yamada, Sakuo; Gotoh, Naomasa; Nishino, Takeshi

    2005-04-01

    The purpose of this study was to evaluate the possible benefit of fosfomycin (FOM) as prophylactic antibiotic in terms of antimicrobial activity and the potential of inducibility of beta-lactamase, compared with cefazolin, cefotiam, cefmetazole, and piperacillin that are commonly used as perioperative agents. The in vitro activity of FOM against aerobic Gram-negative bacteria using Mueller-Hinton agar or nutrient agar supplemented with glucose-6-phosphate (G6P) as tested medium increased within a range from 2 to 256 times the activity in the medium without G6P. However, the susceptibility of Gram-positive bacteria to FOM remained largely unchanged with or without G6P. There was no aerobic- or anaerobic-bacteria which changed susceptibility against beta-lactam antibiotics under various tested medium conditions. FOM demonstrated strong bactericidal activity against Escherichia coli and Pseudomonas aeruginosa in a dose dependent manner, and decreased viable cell counts of Staphylococcus aureus. In the case of P. aeruginosa, transmission electron micrographs study revealed that numerous lysed cells were present 2 hours after treatment with FOM at four times the MIC. First and second generation cephalosporins induced AmpC-type beta-lactamase in a dose dependent manner among beta-lactamase inducible strains of P. aeruginosa and Enterobacter cloacae. On the other hand, inducible activity of FOM on beta-lactamase production was less than 1/25 to 1/65 compared with those of cephalosporins. In addition, FOM maintained strong antimicrobial activity for over then 20 years after marketing, because of the excellent stability against various types of beta-lactamase produced by plasmid-carrying bacteria and clinical isolates. FOM was not extruded by four types of efflux systems, such as MexAB-OprM, MexCD-OprJ, MexXY/ OprM and MexEF-OprN, however beta-lactam antibiotics were substrates of MexAB-OprM and MexCD-OprJ. In conclusion, FOM provides adequate coverage for both aerobic Gram

  19. Beta-Lactams combinations with Vancomycin provide synergy against VSSA, hVISA, and VISA.

    Science.gov (United States)

    Tran, Kieu-Nhi; Rybak, Michael J

    2018-03-19

    Background: Increasing utilization of vancomycin due to the high prevalence of methicillin-resistant S. aureus (MRSA) infections has lead to the emergence of vancomycin-intermediate S. aureus (VISA) and heterogeneous VISA (hVISA). In vitro data suggest the potential for potent synergy between several beta-lactams and vancomycin. The objective of this study is to evaluate the synergy between beta-lactams and vancomycin against MRSA that is vancomycin susceptible, vancomycin susceptible Staphylococcus aureus (VSSA), hVISA, and VISA. Methods: Fifty randomly selected clinical MRSA strains with varying susceptibility to vancomycin were evaluated for vancomycin alone and vancomycin in combination with varying concentrations of cefazolin (CFZ), cefepime (FEP), ceftaroline (CPT), and nafcillin (NAF) minimum inhibitory concentration (MIC). The potential for synergy was assessed by 24h time-kills. Results: Beta-lactams reduced vancomycin MIC values against all strains (4-16 fold reduction). In time-kill studies against MRSA, CFZ, FEP, CPT, and NAF all demonstrated a similar extent of killing at 24h, and all showed synergistic activity with vancomycin against VSSA, hVISA, and VISA. Each of these combinations was also superior to any single agent against isolates of all three phenotypes, and each was bactericidal (P synergy of vancomycin against these Staphylococcus strains. Copyright © 2018 American Society for Microbiology.

  20. Antibiotic Sensitivity of Micrococcus radiodurans

    Science.gov (United States)

    Hawiger, J.; Jeljaszewicz, J.

    1967-01-01

    A wild-type strain of Micrococcus radiodurans and its nonpigmented mutant W1 were tested for sensitivity to 10 antibiotics selected from the standpoint of their mechanism of action. Representatives of groups of antibiotics inhibiting deoxyribonucleic acid (DNA) synthesis, DNA-dependent ribonucleic acid synthesis, protein synthesis, and cell wall synthesis were selected. M. radiodurans and its mutant exhibited full susceptibility to all antibiotics tested (mitomycin C, actinomycin D, chloramphenicol, dihydrostreptomycin, erythromycin, neomycin, kanamycin, benzylpenicillin, bacitracin, and vancomycin), the degree of susceptibility being of the same order as that of a standard strain of Staphylococcus aureus 209 P, with the exception of dihydrostreptomycin. PMID:4166078

  1. Prevalence of beta-lactams resistance among Escherichia coli clinical isolates from a hospital in Algiers.

    Science.gov (United States)

    Messai, Y; Benhassine, T; Naim, M; Paul, G; Bakour, R

    2006-06-01

    A high prevalence of beta-lactams resistance among Enterobacteriaceae have been reported worldwide; however, there are not sufficient data on this issue in Algeria. beta-Lactams susceptibility of 203 Escherichia coli clinical isolates was determined by agar diffusion method, and production of extended-spectrum beta-lactamases (ESBL) was screened by double-disk synergy test. This analysis showed five well-defined phenotypes: 1) 62 isolates (30.5%) were susceptible to all beta-lactams; 2) 135 isolates (66.5%) presented a broad-spectrum beta-lactamases phenotype (BSBL); 3) three isolates (1.5%) were defined as producing ESBLs; 4) two isolates (1%) were AmpC cephalosporinase producers; and 5) one isolate (0.5%) presented a phenotype of cell-decreased permeability to beta-lactams. Isoelectric focusing revealed beta-lactamases with isolectric points of 5.4 or 7.6 for isolates with BSBL phenotype; approximately 9.0 for two ESBL isolates; 5.4, 7.6 and approximately 9.0 for the remaining ESBL isolate; and 5.4 and approximately 9.0 for the AmpC isolates. The cefotaxime hydrolysis corresponds to the basic bands with an isoelectric point of approximately 9.0. Conjugation assay showed transfer of penicillinase and AmpC resistance phenotypes and their corresponding beta-lactamases to recipient E. coli BM21 in association with plasmids of 71.4 kb for the AmpC isolates and from 40-56 kb for penicillinase isolates. This result showed that the AmpC phenotype is plasmid mediated. ESBL isolates were found not to transfer their resistance through conjugation experiment. Polymerase chain reaction (PCR) experiments using primers specific to blaTEM, blaAmpC and blaCTX-M genes showed specific amplification with blaCTX-M primer for two ESBL isolates; blaTEM and blaCTX-M for the remaining ESBL isolate; and blaTEM and blaAmpC for the AmpC isolates and their corresponding transconjugants. The study showed a high rate of isolates producing penicillinase, and low frequencies of AmpC and ESBL

  2. Determination of Beta-Lactam residues in milk by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Roseane Brandão de Brito

    2006-01-01

    Full Text Available A high performance liquid chromatographic method to assay beta-lactam residues in milk was developed and validated. Milk samples were spiked with standard solutions and deproteinated. The extract was cleaned-up on C18 SPE cartridge, the antibiotics eluted with acetonitrile:water (50:50 v/v and derivatized with acetic anhydride and 1-methyl-imidazole solution containing HgCl2. The chromatographic analysis was performed on C18 column using mobile phase consisting of acetonitrile and phosphate buffer (pH 6.5 in the presence of Na2S2O3 gradient and detection at 325 nm. The method was selective for ampicillin, penicillin G and penicillin V, the latter used as internal standard. Average recoveries for ampicillin and penicillin G ranged, respectively, from 60.0% to 104.9% and from 82.7% to 109.2%, with coefficients of variation from 11.1% to 24.6%, and from 2.1% to 25.2%, indicating accuracy and precision. Detection limit of 4.0 µg/L for ampicillin and 3.0 µg/L for penicillin G, and quantification limits of 4.0 µg/L for both were estimated.Um método para determinar resíduos de antibióticos beta-lactâmicos em leite por cromatografia líquida de alta eficiência (CLAE foi desenvolvido e validado. Amostras brancas foram adicionadas de padrão e desproteinizadas. O extrato foi purificado por extração em fase sólida C18, os antibióticos eluídos com acetonitrila:água (50:50 v/v e posteriormente derivatizados com anidrido acético e solução de 1-metil-imidazol contendo HgCl2. A análise cromatográfica foi realizada utilizando coluna C18, fase móvel composta por acetonitrila e tampão fosfato pH 6,5, na presença de Na2S2O3 em gradiente e detecção a 325 nm. O método foi seletivo para ampicilina, penicilina G e penicilina V, sendo este último utilizado como padrão interno. As médias de recuperação para ampicilina e penicilina G situaram-se, respectivamente, na faixa de 60,0% a 104,9% e de 82,7% a 109,2%, com coeficientes de varia

  3. Validation of the charm 3 SL3 beta-lactam test for screening raw milk in compliance with the U.S. pasteurized milk ordinance. Performance Tested Method 071002.

    Science.gov (United States)

    Salter, Robert S; Douglas, David; McRobbie, Lindsey; Quintana, Julio; Legg, David; Schwartz, Janine; Conaway, David; McPhee, Carla; Saul, Steven; Markovsky, Robert

    2011-01-01

    The Charm 3 SL3 beta-Lactam Test is a 3 min receptor-based lateral-flow Rapid One-Step Assay (ROSA) that detects the six beta-lactam drugs of concern approved for dairy cattle in the United States. The method is a biochemical formulation change of the SL3 beta-Lactam Test evaluated and approved in 2007. The Charm 3 SL3 was evaluated under the AOAC Research Institute Performance Tested Method (PTM) program following the protocol of the U.S. Food and Drug Administration, Center for Veterinary Medicine. The method was approved as PTM 071002 on May 8, 2009. The following drugs were detected in three combined lots: penicillin G at 3.8 ppb, ampicillin at 8.0 ppb, amoxicillin at 8.4 ppb, cephapirin at 20.0 ppb, ceftiofur (total metabolites) at 79 ppb, and cloxacillin at 8.6 ppb > or = 90% of the time with 95% confidence. These detection levels are lower than, but within 75% of, the U.S. Safe Level/Tolerances. Lot-to-lot repeatability was typically within 20% of these determined levels. The test kit was found to be suitable for testing thawed frozen samples. It was also found to respond with equal or better sensitivity to samples that contained incurred analytes, i.e., both the microbiologically active parent drug and its active metabolites. There were no interferences from somatic cells at 1.1 million/mL, bacterial cells at 300 000 CFU/mL, or 32 other non-beta-lactam drugs at 100 ppb. Ruggedness experiments indicated that the test procedure is robust. These results meet the fit-for-purpose approval criteria for inclusion in the National Conference for Interstate Milk Shipments milk testing program.

  4. Characterization of Coagulase-Negative Staphylococci and pheno-genotypic beta lactam resistance evaluation in samples from bovine Intramammary infection

    Directory of Open Access Journals (Sweden)

    D.A. Melo

    Full Text Available ABSTRACT This study aimed to identify Coagulase-Negative Staphylococci (CoNS species isolated from bovine mastitis, through phenotypic and PCR-RFLP (Restriction Fragment Length Polymorphism-Polimerase Chain Reaction methods and to compare both techniques to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS technique. Among them, the PCR-RFLP method, using a partially conserved sequence of the groEL gene, is a promising alternative, because of its reproducibility and reliability. On the other hand, the proteomic technique MALDI-TOF MS provides an accurate and much faster diagnosis and has been increasingly employed in microbiological identification. The pheno-genotypic profiles of beta-lactam resistance were also investigated, this characterization is important, considering that the use of antimicrobials is a key element for mastitis control in dairy farms. The concordance of the phenotypic, PCR-RFLP and MALDI-TOF MS assays to identify CoNS species was 77,5% (31/40. S. chromogenes was the species most frequently isolated. Antibiotic resistance rate was relatively low, registering values of 25.5% to penicillin, 9.6% to oxacillin and 6.2% to cefoxitin. Resistance to imipenem, cephalotin and amoxicillin+clavulanate was not observed. The mecA gene and its variant were detected in 7.6% and 4,1% of the isolates respectively. The blaZ gene was found in 43.2% of the strains resistant to penicillin.

  5. Biofilm production and beta-lactamic resistance in Brazilian Staphylococcus aureus isolates from bovine mastitis

    Directory of Open Access Journals (Sweden)

    Viviane Figueira Marques

    Full Text Available Abstract Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo.

  6. In vitro effects of beta-lactams combined with beta-lactamase inhibitors against methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Kobayashi, S; Arai, S; Hayashi, S; Sakaguchi, T

    1989-01-01

    The effects of combinations of beta-lactams with two beta-lactamase inhibitors, sulbactam and clavulanic acid, were determined in vitro against 22 clinical isolates of methicillin-resistant Staphylococcus aureus. Combinations of cefpirome, cefotaxime, and cefazolin with sulbactam (10 micrograms/ml) showed synergistic effects against more than 70% of the strains. Combinations of methicillin and penicillin G with sulbactam also showed synergistic effects against 50 and 68% of the strains, respectively, while cefotiam, moxalactam, flomoxef, and cefmetazole in combination with sulbactam showed such effects against only 40% or fewer. Clavulanic acid was synergistic only when combined with penicillin G, the effect probably being due to the beta-lactamase inhibition by the inhibitor. Sulbactam did not improve the antimicrobial activities of the beta-lactams against methicillin-susceptible S. aureus strains. At 42 degrees C the MICs of cefotaxime, methicillin, and flomoxef alone were markedly decreased from the values at 35 degrees C, and no synergy between these beta-lactams and sulbactam appeared. The resistance to penicillin G was not inhibited by incubation at 42 degrees C, and combinations of penicillin G with sulbactam and clavulanic acid showed synergy. The amounts of beta-lactamase produced were not related to the decreases in the MICs of the beta-lactams, except for penicillin G combined with sulbactam. Clavulanic acid showed slightly stronger beta-lactamase-inhibiting activity than sulbactam did. These results suggest that the synergy between sulbactam and the beta-lactams, except for penicillin G, may not be due to beta-lactamase inhibition but to suppression of the methicillin-resistant S. aureus-specific resistance based on other factors. PMID:2786369

  7. Antibiotic Administration and Factors Influencing the Vaginal Microbiota during Pregnancy

    DEFF Research Database (Denmark)

    Stokholm, Jakob

    2012-01-01

    cohort. In study I we described the usage of antibiotics; (1) in pregnancy as oral antibiotics subdivided into groups; urinary tract infection (UTI) antibiotics, beta-lactams and other antibiotics, and (2) during birth as intrapartum antibiotics. Furthermore we examined whether the usage of both oral...... antibiotic treatments was increased in the lower educated women. Younger women and smokers had an increased usage of UTI antibiotics and asthmatic women had an increased usage of beta-lactams. Administration of intrapartum antibiotics was increased in smokers, in women giving birth at a lower gestational age...... were associated to treatment with UTI antibiotics. Women treated in the third trimester of pregnancy were more often colonized by E. coli. This change was associated to beta-lactam treatment. We did not observe any significant changes in vaginal group B Streptococcus (GBS) following antibiotic...

  8. In vitro selection of resistance in haemophilus influenzae by 4 quinolones and 5 beta-lactams.

    Science.gov (United States)

    Clark, Catherine; Kosowska, Klaudia; Bozdogan, Bülent; Credito, Kim; Dewasse, Bonifacio; McGhee, Pamela; Jacobs, Michael R; Appelbaum, Peter C

    2004-05-01

    We tested abilities of ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, amoxicillin, amoxicillin/clavulanate, cefixime, cefpodoxime, and cefdinir to select resistant mutants in 5 beta-lactamase positive and 5 beta-lactamase negative Haemophilus influenzae strains by single and multistep methodology. In multistep tests, amoxicillin, amoxicillin/clavulanate and cefpodoxime exposure did not cause >4-fold minimum inhibitory concentration (MIC) increase after 50 days. One mutant selected by cefdinir had one amino acid substitution (Gly490Glu) in PBP3 and became resistant to cefdinir. Cefixime exposure caused 8-fold MIC-increase in 1 strain with TEM but the mutant remained cefixime susceptible and had no alteration in PBP3 or TEM. Among 10 strains tested, ciprofloxacin, moxifloxacin, gatifloxacin, levofloxacin caused >4-fold MIC increase in 6, 6, 5, and 2 strain, respectively. Despite the increases in quinolone MICs, none of the mutants became resistant to quinolones by established criteria. Quinolone selected mutants had quindone resistance-determining region (QRDR) alterations in GyrA, GyrB, ParC, ParE. Four quinolone mutants had no QRDR alterations. Among beta-lactams cefdinir and cefixime selected one mutant each with higher MICs however amoxicillin, amoxicillin/clavulanate, and cefpodoxime exposure did not select resistant mutants.

  9. Evaluation of the sensitizing potential of antibiotics in vitro using the human cell lines THP-1 and MUTZ-LC and primary monocyte‐derived dendritic cells

    International Nuclear Information System (INIS)

    Sebastian, Katrin; Ott, Hagen; Zwadlo-Klarwasser, Gabriele; Skazik-Voogt, Claudia; Marquardt, Yvonne; Czaja, Katharina; Merk, Hans F.; Baron, Jens Malte

    2012-01-01

    Since the 7th amendment to the EU cosmetics directive foresees a complete ban on animal testing, alternative in vitro methods have been established to evaluate the sensitizing potential of small molecular weight compounds. To find out whether these novel in vitro assays are also capable to predict the sensitizing potential of small molecular weight drugs, model compounds such as beta-lactams and sulfonamides – which are the most frequent cause of adverse drug reactions – were co-incubated with THP-1, MUTZ-LC, or primary monocyte‐derived dendritic cells for 48 h and subsequent expression of selected marker genes (IL-8, IL-1β, CES1, NQO1, GCLM, PIR and TRIM16) was studied by real time PCR. Benzylpenicillin and phenoxymethylpenicillin were recognized as sensitizing compounds because they are capable to induce the mRNA expression of these genes in moDCs and, except for IL-8, in THP-1 cells but not in MUTZ-LC. Ampicillin stimulated the expression of some marker genes in moDCs and THP-1 cells. SMX did not affect the expression of these genes in THP-1, however, in moDCs, at least PIR was enhanced and there was an increase of the release of IL-8. These data reveal that novel in vitro DC based assays might play a role in the evaluation of the allergenic potential of novel drug compounds, but these systems seem to lack the ability to detect the sensitizing potential of prohaptens that require metabolic activation prior to sensitization and moDCs seem to be superior with regard to the sensitivity compared with THP-1 and MUTZ-3 cell lines. -- Highlights: ► We tested the sensitizing potential of small molecular weight drugs in vitro. ► In vitro assays were performed with moDCs and THP-1 cells. ► Beta-lactam antibiotics can be recognized as sensitizing compounds. ► They affect the expression of metabolic enzymes, cytokines and transcription factors. ► Sulfamethoxazole has no measurable effect on THP-1 cells and moDCs.

  10. Evaluation of the sensitizing potential of antibiotics in vitro using the human cell lines THP-1 and MUTZ-LC and primary monocyte‐derived dendritic cells

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, Katrin, E-mail: ksebastian@ukaachen.de [Department of Dermatology and Allergology, RWTH Aachen University Hospital, D-52074 Aachen (Germany); Ott, Hagen [Department of Dermatology and Allergology, RWTH Aachen University Hospital, D-52074 Aachen (Germany); Zwadlo-Klarwasser, Gabriele [IZKF (BIOMAT), RWTH Aachen University Hospital, D-52074 Aachen (Germany); Skazik-Voogt, Claudia; Marquardt, Yvonne; Czaja, Katharina; Merk, Hans F.; Baron, Jens Malte [Department of Dermatology and Allergology, RWTH Aachen University Hospital, D-52074 Aachen (Germany)

    2012-08-01

    Since the 7th amendment to the EU cosmetics directive foresees a complete ban on animal testing, alternative in vitro methods have been established to evaluate the sensitizing potential of small molecular weight compounds. To find out whether these novel in vitro assays are also capable to predict the sensitizing potential of small molecular weight drugs, model compounds such as beta-lactams and sulfonamides – which are the most frequent cause of adverse drug reactions – were co-incubated with THP-1, MUTZ-LC, or primary monocyte‐derived dendritic cells for 48 h and subsequent expression of selected marker genes (IL-8, IL-1β, CES1, NQO1, GCLM, PIR and TRIM16) was studied by real time PCR. Benzylpenicillin and phenoxymethylpenicillin were recognized as sensitizing compounds because they are capable to induce the mRNA expression of these genes in moDCs and, except for IL-8, in THP-1 cells but not in MUTZ-LC. Ampicillin stimulated the expression of some marker genes in moDCs and THP-1 cells. SMX did not affect the expression of these genes in THP-1, however, in moDCs, at least PIR was enhanced and there was an increase of the release of IL-8. These data reveal that novel in vitro DC based assays might play a role in the evaluation of the allergenic potential of novel drug compounds, but these systems seem to lack the ability to detect the sensitizing potential of prohaptens that require metabolic activation prior to sensitization and moDCs seem to be superior with regard to the sensitivity compared with THP-1 and MUTZ-3 cell lines. -- Highlights: ► We tested the sensitizing potential of small molecular weight drugs in vitro. ► In vitro assays were performed with moDCs and THP-1 cells. ► Beta-lactam antibiotics can be recognized as sensitizing compounds. ► They affect the expression of metabolic enzymes, cytokines and transcription factors. ► Sulfamethoxazole has no measurable effect on THP-1 cells and moDCs.

  11. Beta-lactamic resistance profiles in Porphyromonas, Prevotella, and Parvimonas species isolated from acute endodontic infections.

    Science.gov (United States)

    Montagner, Francisco; Jacinto, Rogério Castilho; Correa Signoretti, Fernanda Graziela; Scheffer de Mattos, Vanessa; Grecca, Fabiana Soares; Gomes, Brenda Paula Figueiredo de Almeida

    2014-03-01

    Susceptibility to beta-lactamic agents has changed among anaerobic isolates from acute endodontic infections. The aim of the present study was to determine the prevalence of the cfxA/cfxA2 gene in Prevotella spp., Porphyromonas spp., and Parviomonas micra strains and show its phenotypic expression. Root canal samples from teeth with acute endodontic infections were collected and Porphyromonas, Prevotella, and Parvimonas micra strains were isolated and microbiologically identified with conventional culture techniques. The susceptibility of the isolates was determined by the minimum inhibitory concentration of benzylpenicillin, amoxicillin, and amoxicillin + clavulanate using the E-test method (AB BIODISK, Solna, Sweden). The presence of the cfxA/cfxA2 gene was determined through primer-specific polymerase chain reaction. The nitrocefin test was used to determine the expression of the lactamase enzyme. Prevotella disiens, Prevotella oralis, Porphyromonas gingivalis, and P. micra strains were susceptible to benzylpenicillin, amoxicillin, and amoxicillin + clavulanate. The cfxA/cfxA2 gene was detected in 2 of 29 isolates (6.9%). Simultaneous detection of the cfxA/cfxA2 gene and lactamase production was observed for 1 Prevotella buccalis strain. The gene was in 1 P. micra strain but was not expressed. Three strains were positive for lactamase production, but the cfxA/cfxA2 gene was not detected through polymerase chain reaction. There is a low prevalence of the cfxA/cfxA2 gene and its expression in Porphyromonas spp., Prevotella spp., and P. micra strains isolated from acute endodontic infections. Genetic and phenotypic screening must be performed simultaneously to best describe additional mechanisms involved in lactamic resistance for strict anaerobes. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Reversible antibiotic tolerance induced in Staphylococcus aureus by concurrent drug exposure

    DEFF Research Database (Denmark)

    Haaber, Jakob Krause; Friberg, Cathrine; McCreary, Mark

    2015-01-01

    UNLABELLED: Resistance of Staphylococcus aureus to beta-lactam antibiotics has led to increasing use of the glycopeptide antibiotic vancomycin as a life-saving treatment for major S. aureus infections. Coinfection by an unrelated bacterial species may necessitate concurrent treatment with a second...... antibiotic that targets the coinfecting pathogen. While investigating factors that affect bacterial antibiotic sensitivity, we discovered that susceptibility of S. aureus to vancomycin is reduced by concurrent exposure to colistin, a cationic peptide antimicrobial employed to treat infections by Gram......-negative pathogens. We show that colistin-induced vancomycin tolerance persists only as long as the inducer is present and is accompanied by gene expression changes similar to those resulting from mutations that produce stably inherited reduction of vancomycin sensitivity (vancomycin-intermediate S. aureus [VISA...

  13. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

  14. Common Bacterial Pathogens and their Antibiotic Sensitivity

    African Journals Online (AJOL)

    these three drugs can be used in treating most from this study suggest that these three drugs can be used in treating most bacterial infections. This would be particularly useful in health set-ups where culturing and sensitivity testing is impossible, although the availability and cost effectiveness of these antibiotics is in ...

  15. Determinants of antibiotic prescription in paediatric patients: The ...

    African Journals Online (AJOL)

    ... differences (p>0.05) in the prescription rates of the hospitals. The most commonly used antibiotics were beta-lactams (57.3%), aminoglycosides (28.3%) and co-trimoxazole (9.4%). Antibiotics were prescribed in all cases of bronchopneumonia, fever, sepsis and acute gastroenteritis. For malaria and undefined diagnoses, ...

  16. Species-specific sensitivity of coagulase-negative Staphylococci to single antibiotics and their combinations.

    Science.gov (United States)

    Szymańska, Grazyna; Szemraj, Magdalena; Szewczyk, Eligia M

    2011-01-01

    The activity of beta-lactam antibiotics (oxacillin, cloxacillin, cephalotin), vancomycin, gentamicin and rifampicin applied in vitro individually and in combination against 37 nosocomial methicillin-resistant strains of coagulase-negative staphylococci (CNS) was assessed to demonstrate the heterogeneity of this group of bacteria and estimate the chance of the efficacy of such therapy. The strains belonged to four species: Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus cohnii, Staphylococcus hominis. They originated from a hospital environment and from the skin of medical staff of the intensive care unit of a paediatric ward at a university hospital. All strains were methicillin-resistant, according to CLSI standards, but individual strains differed in MIC(ox) values. Susceptibility to other tested antibiotics was also characteristic for the species. The increased susceptibility to antibiotics in combinations, tested by calculating the fractional inhibitory concentration (FIC) index, concerned 26 out of 37 investigated strains and it was a feature of a particular species. Combinations of vancomycin and cephalotin against S. epidermidis and oxacillin with vancomycin were significant, as well as cephalotin and rifampicin in growth inhibition of multiresistant S. haemolyticus strains.

  17. Testing the sensitivity of Staphylococcus aureus antibiotics

    Directory of Open Access Journals (Sweden)

    Marioara Nicoleta FILIMON

    2009-11-01

    Full Text Available This study has in view to establish and test the sensitivity of Staphylococcus aureus antibiotics. There are different injuries caused by superficial skin infections: from simple pimples to infections that endanger our lives, like an abscess, furuncle septicemia, meningitis, toxic food, urinary tract infection at sexually active young women. Samples have been taken from 30 people with staphylococcus infections. They were nineteen women and eleven men, between the age of 2 and 79. During this study some antibiograms have been made, based on pharyngeal exudates, acne secretion and urine culture. It has been established that the most efficient recommended antibiotics are: oxacilin, erythromycin, rifampicin and ciprofloxacin. The penicillin turned out to be less efficient to remove and destroy the Staphylococcus aureus species.

  18. Analysis of antibiotic resistance pattern of S. aureus strains isolated from the Orthopedics-Traumatology Section of "Sf. Spiridon" Clinical Emergency Hospital, Iaşi.

    Science.gov (United States)

    Tucaliuc, D; Alexa, O; Tuchiluş, Cristina Gabriela; Ursu, Ramona Gabriela; Tucaliuc, Elena Simona; Iancu, Luminiţa Smaranda

    2014-01-01

    The retrospective analysis of antibiotic sensibility of S. aureus strains isolated from infected patients from the Orthopedics-Traumatology Clinic of "Sf. Spiridon" Clinical Emergency Hospital, Iaşi during January 2003-December 2013, in view of determining the evolution trend of the resistance phenomenon and of pinpointing the most useful treatment for these strains. The antibiotic sensitivity test was carried out using two methods: diffusimetric-Kirby-Bauer and the MIC determination by E-test (for the strains isolated in 2013); the interpretation of the sensitivity was made in a standardized manner, in compliance with the CLSI (Clinical and Laboratory Standards Institute) standard for antibiotics testing in force. The sensitivity testing for beta-lactams proved that during the 11 years of the study, the average value of the frequency of resistant strains was of 41.59% +/- 8.68. The highest frequency of MRSA (Methicillin Restant S. aureus) strains was noticed in 2012 (58.6%), followed by 2004 (50.7%). Even if in 2013 it dropped to 38.9%, the trend calculated for 2003-2013 is slightly rising (y = 0.0073x + 0.372). Out of the total of 495 S. aureus strains that were isolated, 164 (33.13%) were completely sensitive to the tested antibiotics and 26 (5.25%) were resistant only to beta-lactams. The other MRSA strains associated multiple resistance and MIC for vancomycin varied between 0.5-2 mg/ml. Two strains whose MIC was of 0.5 mg/ml were sensitive to most classes of tested antibiotics, including beta-lactams, except for macrolides (erythromycin), and the strain whose MIC was of 2 mg/ml, was resistant to all classes of tested antibiotics, except for glycopeptides and oxazolidiones. The other tested strains had a MIC for vancomycin equal to 1 mg/ml. Due to the fact that there are infections with SAMR strains in a rather worrying percentage (53.9%) that are resistant to the other classes of antibiotics, the only therapeutic solution being the vancomycin treatment, its

  19. Pseudomonas aeruginosa chromosomal beta-lactamase in patients with cystic fibrosis and chronic lung infection. Mechanism of antibiotic resistance and target of the humoral immune response

    DEFF Research Database (Denmark)

    Ciofu, Oana

    2003-01-01

    the development of resistance to beta-lactam antibiotics and the occurrence of high beta-lactamase producing strains and between the MIC of the beta-lactams and the levels of beta-lactamase expression. Partially derepressed mutants, characterized by high basal levels of beta-lactamase with the possibility...... of induction to even higher levels during treatment with beta-lactam antibiotics, were the most frequent phenotype found among resistant Danish P. aeruginosa CF isolates. We have also shown that the high alginate producing P. aeruginosa isolates, that characterize the chronic lung infection in CF patients......, are more susceptible to antibiotics and produce less beta-lactamase than the non-mucoid paired isolates. We propose that the non-mucoid isolates are exposed to a relatively higher antibiotic pressure than the mucoid isolates and therefore, they become easily antibiotic resistant and in consequence produce...

  20. Practical Management of Patients with a History of Immediate Hypersensitivity to Common non-Beta-Lactam Drugs.

    Science.gov (United States)

    Macy, Eric

    2016-01-01

    Immediate hypersensitivity reactions to medications are among the most feared adverse drug reactions, because of their close association with anaphylaxis. This review discusses a practical management approach for patients with a history of an immediate hypersensitivity to a non-beta-lactam medication, where reexposure to the implicated, or similar, medication is clinically necessary. Mechanisms associated with severe immediate hypersensitivity reactions include IgE-mediated mast cell activation, complement-mediated mast cell activation, and direct mast cell activation. Immediate hypersensitivity reactions may also be mediated by vasodilators, other pharmacologic mechanisms, or be secondary to underlying patient-specific biochemical abnormalities such as endocrine tumors or chronic spontaneous urticaria. The key features in the reaction history and the biochemistry of the implicated medication are discussed. Most individuals with a history of immediate hypersensitivity to a medication, who require reuse of that drug, can be safely retreated with a therapeutic course of the implicated drug after a full-dose challenge, graded challenge, or desensitization, with or without premedication and/or any preliminary diagnostic testing, depending on the specific situation.

  1. Development of a new family of conformationally restricted peptides as potent nucleators of beta-turns. Design, synthesis, structure, and biological evaluation of a beta-lactam peptide analogue of melanostatin.

    Science.gov (United States)

    Palomo, Claudio; Aizpurua, Jesus M; Benito, Ana; Miranda, José Ignacio; Fratila, Raluca M; Matute, Carlos; Domercq, Maria; Gago, Federico; Martin-Santamaria, Sonsoles; Linden, Anthony

    2003-12-31

    Novel enantiopure (i)-(beta-lactam)-(Gly)-(i+3) peptide models, defined by the presence of a central alpha-alkyl-alpha-amino-beta-lactam ring placed as the (i+1) residue, have been synthesized in a totally stereocontrolled way by alpha-alkylation of suitable N-[bis(trimethylsilyl)methyl]-beta-lactams. The structural properties of these beta-lactam pseudopeptides have been studied by X-ray crystallography, Molecular Dynamics simulation, and NOESY-restrained NMR simulated annealing techniques, showing a strong tendency to form stable type II or type II' beta-turns either in the solid state or in highly coordinating DMSO solutions. Tetrapeptide models containing syn- or anti-alpha,beta-dialkyl-alpha-amino-beta-lactam rings have also been synthesized and their conformations analyzed, revealing that alpha-alkyl substitution is essential for beta-turn stabilization. A beta-lactam analogue of melanostatin (PLG amide) has also been prepared, characterized as a type-II beta-turn in DMSO-d6 solution, and tested by competitive binding assay as a dopaminergic D2 modulator in rat neuron cultured cells, displaying moderate agonist activity in the micromolar concentration range. On the basis of these results, a novel peptidomimetic design concept, based on the separation of constraint and recognition elements, is proposed.

  2. Enzyme activities and antibiotic susceptibility of colonial variants of Bacillus subtilis and Bacillus licheniformis.

    OpenAIRE

    Carlisle, G E; Falkinham, J O

    1989-01-01

    A nonmucoid colonial variant of a mucoid Bacillus subtilis strain produced less amylase activity and a transparent colonial variant of a B. licheniformis strain produced less protease activity compared with their parents. Antibiotic susceptibility patterns of the colonial variants differed, and increased resistance to beta-lactam antibiotics was correlated with increased production of extracellular beta-lactamase.

  3. Enhancement of antibiotic effect via gold:silver-alloy nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Moreira dos Santos, Margarida, E-mail: margarida.santos@fct.unl.pt; Queiroz, Margarida Joao; Baptista, Pedro V. [Universidade Nova de Lisboa, CIGMH, Departamento Ciencias da Vida, Faculdade de Ciencias e Tecnologia (Portugal)

    2012-05-15

    A strategy for the development of novel antimicrobials is to combine the stability and pleiotropic effects of inorganic compounds with the specificity and efficiency of organic compounds, such as antibiotics. Here we report on the use of gold:silver-alloy (Au:Ag-alloy) nanoparticles, obtained via a single-step citrate co-reduction method, combined to conventional antibiotics to enhance their antimicrobial effect on bacteria. Addition of the alloy nanoparticles considerably decreased the dose of antibiotic necessary to show antimicrobial effect, both for bacterial cells growing in rich medium in suspension and for bacterial cells resting in a physiological buffer on a humid cellulose surface. The observed effect was more pronounced than the sum of the individual effects of the nanoparticles and antibiotic. We demonstrate the enhancement effect of Au:Ag-alloy nanoparticles with a size distribution of 32.5 {+-} 7.5 nm mean diameter on the antimicrobial effect of (i) kanamycin on Escherichia coli (Gram-negative bacterium), and (ii) a {beta}-lactam antibiotic on both a sensitive and resistant strain of Staphylococcus aureus (Gram-positive bacterium). Together, these results may pave the way for the combined use of nanoparticle-antibiotic conjugates towards decreasing antibiotic resistance currently observed for certain bacteria and conventional antibiotics.

  4. Beta-lactam resistance among Enterobacteriaceae in Cambodia: The four-year itch

    Directory of Open Access Journals (Sweden)

    Yannick Caron

    2018-01-01

    Full Text Available Although antibiotics are too often used inappropriately in Cambodia, published data on antimicrobial resistance in this country are scarce. Epidemic dissemination and the transfer of resistance genes to other bacterial species put the population at risk. The aim of this study was to evaluate the frequency and characteristics of extended-spectrum beta-lactamase (ESBL-producing Enterobacteriaceae (ESBL-E isolated in consecutive samples tested at Institut Pasteur du Cambodge over a 4-year period (2012–2015. Antimicrobial susceptibility testing was performed by disk diffusion on agar technique and the results were read automatically using an OSIRIS system. The Etest was used to determine minimum inhibitory concentrations (MIC for some resistance phenotypes. The strain most commonly identified was Escherichia coli (63.9%. The proportion of ESBL-E increased gradually over the study period, from 23.8% to 38.4%. ESBL was detected in 42.7% of the E. coli strains and 33.7% of all Klebsiella pneumoniae isolated. The proportion of ESBL-producing E. coli increased significantly from 28.9% in 2012 to 48.2% in 2015, while the increase for K. pneumoniae remained non-significant. Multidrug resistance was high in this Cambodian series, with some strains displaying resistance to all antibiotics available in the country. There is currently no established system for the surveillance of antimicrobial resistance in Cambodia. Collecting samples from clinical settings throughout the country is critical to assess the impact of antimicrobial drug use in patients in Cambodia and in the Mekong Region.

  5. Beta-lactam resistance among Enterobacteriaceae in Cambodia: The four-year itch.

    Science.gov (United States)

    Caron, Yannick; Chheang, Rattanak; Puthea, Nop; Soda, Meng; Boyer, Sébastien; Tarantola, Arnaud; Kerléguer, Alexandra

    2018-01-01

    Although antibiotics are too often used inappropriately in Cambodia, published data on antimicrobial resistance in this country are scarce. Epidemic dissemination and the transfer of resistance genes to other bacterial species put the population at risk. The aim of this study was to evaluate the frequency and characteristics of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) isolated in consecutive samples tested at Institut Pasteur du Cambodge over a 4-year period (2012-2015). Antimicrobial susceptibility testing was performed by disk diffusion on agar technique and the results were read automatically using an OSIRIS system. The Etest was used to determine minimum inhibitory concentrations (MIC) for some resistance phenotypes. The strain most commonly identified was Escherichia coli (63.9%). The proportion of ESBL-E increased gradually over the study period, from 23.8% to 38.4%. ESBL was detected in 42.7% of the E. coli strains and 33.7% of all Klebsiella pneumoniae isolated. The proportion of ESBL-producing E. coli increased significantly from 28.9% in 2012 to 48.2% in 2015, while the increase for K. pneumoniae remained non-significant. Multidrug resistance was high in this Cambodian series, with some strains displaying resistance to all antibiotics available in the country. There is currently no established system for the surveillance of antimicrobial resistance in Cambodia. Collecting samples from clinical settings throughout the country is critical to assess the impact of antimicrobial drug use in patients in Cambodia and in the Mekong Region. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. Moellerella wisconsensis: identification, natural antibiotic susceptibility and its dependency on the medium applied.

    Science.gov (United States)

    Stock, Ingo; Falsen, Enevold; Wiedemann, Bernd

    2003-01-01

    The present study establishes a data compilation on biochemical features and natural antibiotic susceptibilities of Moellerella wisconsensis strains. 17 moellerellae isolated from humans (n = 11), food (n = 5) and water (n = 1) were tested. Identification was carried out using two commercially available systems and conventional tests. MIC determinations of 74 antibiotics were performed applying a microdilution procedure in Cation-adjusted Mueller Hinton broth and IsoSensitest broth. M. wisconsensis was naturally sensitive to doxycycline, minocycline, all tested aminoglycosides, numerous beta-lactams, all fluoroquinolones, folate-pathway inhibitors, chloramphenicol and nitrofurantoin. Natural resistance was found with oxacillin, penicillin G, all tested macrolides, lincomycin, streptogramins, ketolides, glycopeptides, fusidic acid, linezolid and rifampicin. Medium-dependent differences in susceptibility affecting clinical assessment criteria were seen with tetracycline, clindamycin and fosfomycin. From the data of the present study it is possible that some moellerellae are misidentified as Klebsiella pneumoniae subsp. ozaenae.

  7. Antibiotic resistance of coagulase-negative staphylococci isolated from artisanal Naples-type salami.

    Science.gov (United States)

    Mauriello, G; Moschetti, G; Villani, F; Blaiotta, G; Coppola, S

    2000-01-01

    In the present paper 42 isolates from Italian salami were specified as Staphylococcus xylosus (30), Staph. capitis (1), Staph. saprophyticus (1), Staph. hominis (1), Staph. simulans (1), Staph. cohnii (1) and as Staph. spp. (7). These strains were coagulase-negative and were examined for resistance/sensitivity against 25 antibiotics including beta-lactams (7), macrolides (3), amynoglicosides (5), glycopeptides, lincosamides (4) and novobiocin, fusidic acid, chloramphenicol, rifampicin, tetracycline, minocycline. More than 64% of the strains were resistant to lincomycin, penicillin G, amoxicillin, fusidic acid and novobiocin. All the strains were multiresistant and displayed at least three resistances. Over 75% had a multiple antibiotic resistance (MAR) index between 0.2 and 0.5.

  8. Targeted simplification versus antipseudomonal broad-spectrum beta-lactams in patients with bloodstream infections due to Enterobacteriaceae (SIMPLIFY): a study protocol for a multicentre, open-label, phase III randomised, controlled, non-inferiority clinical trial.

    Science.gov (United States)

    López-Cortés, Luis Eduardo; Rosso-Fernández, Clara; Núñez-Núñez, María; Lavín-Alconero, Lucía; Bravo-Ferrer, José; Barriga, Ángel; Delgado, Mercedes; Lupión, Carmen; Retamar, Pilar; Rodríguez-Baño, Jesús

    2017-06-09

    Within the context of antimicrobial stewardship programmes, de-escalation of antimicrobial therapy is one of the proposed strategies for reducing the unnecessary use of broad-spectrum antibiotics (BSA). The empirical treatment of nosocomial and some healthcare-associated bloodstream infections (BSI) frequently includes a beta-lactam with antipseudomonal activity as monotherapy or in combination with other drugs, so there is a great opportunity to optimise the empirical therapy based on microbiological data. De-escalation is assumed as standard of care for experts in infectious diseases. However, it is less frequent than it would desirable. The SIMPLIFY trial is a multicentre, open-label, non-inferiority phase III randomised controlled clinical trial, designed as a pragmatic 'real-practice' trial. The aim of this trial is to demonstrate the non-inferiority of de-escalation from an empirical beta-lactam with antipseudomonal activity to a targeted narrow-spectrum antimicrobial in patients with BSI due to Enterobacteriaceae . The primary outcome is clinical cure, which will be assessed at the test of cure visit. It will be conducted at 19 Spanish public and university hospitals. Each participating centre has obtained the approval of the ethics review committee, the agreement of the directors of the institutions and authorisation from the Spanish Regulatory Agency (Agencia Española del Medicamento y Productos Sanitarios). Data will be presented at international conferences and published in peer-reviewed journals. Strategies to reduce the use of BSA should be a priority. Most of the studies that support de-escalation are observational, retrospective and heterogeneous. A recent Cochrane review stated that well-designed clinical trials should be conducted to assess the safety and efficacy of de-escalation. The European Union Clinical Trials Register: EudraCT number 2015-004219-19. Clinical trials.gov: NCT02795949. Protocol version: V.2.0, dated 16 May 2016. All items from

  9. Antibiotic Resistance Patterns in Invasive Group B Streptococcal Isolates

    Directory of Open Access Journals (Sweden)

    Mei L. Castor

    2008-01-01

    Full Text Available Antibiotics are used for both group B streptococcal (GBS prevention and treatment. Active population-based surveillance for invasive GBS disease was conducted in four states during 1996—2003. Of 3813 case-isolates, 91.0% (3471 were serotyped, 77.1% (2937 had susceptibility testing, and 46.6% (3471 had both. All were sensitive to penicillin, ampicillin, cefazolin, cefotaxime, and vancomycin. Clindamycin and erythromycin resistance was 12.7% and 25.6%, respectively, and associated with serotype V (P<.001. Clindamycin resistance increased from 10.5% to 15.0% (X2 for trend 12.70; P<.001; inducible clindamycin resistance was associated with the erm genotype. Erythromycin resistance increased from 15.8% to 32.8% (X2 for trend 55.46; P<.001. While GBS remains susceptible to beta-lactams, resistance to alternative agents such as erythromycin and clindamycin is an increasing concern.

  10. Synthetic Beta-Lactam Antibiotics as a Selective Breast Cancer Cell Apoptosis Inducer: Significance in Breast Cancer Prevention and Treatment

    Science.gov (United States)

    2007-03-01

    References 1. Labbe S, Thiele DJ: Pipes and wiring: the regulation of copper uptake and distribution in yeast . Trends Microbiol 1999, 7:500-505. 2. Aggett...inhibitors. New agents in cancer therapy. Drugs Aging 2000, 17:249-255. 8. Brewer GJ: Copper control as an antiangiogenic anticancer therapy: lessons... Brewer GJ, Dick RD, Grover DK, LeClaire V, Tseng M, Wicha M, Pienta K, Redman BG, Jahan T, Sondak VK, et al.: Treatment of metastatic cancer with

  11. Synthetic Beta-Lactam Antibiotics as a Selective Breast Cancer Cell Apoptosis Inducer: Significance in Breast Cancer Prevention and Treatment

    Science.gov (United States)

    2008-03-01

    Hoechst 33258, cremophore, dimethylsulfoxide ( DMSO ) and trypan blue were purchased from Sigma-Aldrich (St. Louis, MO). Apoptag peroxidase in situ...treated with solvent ( DMSO ), 50 or 100 μM of each indicated compound for 24 h, followed by trypan blue exclusion assay. (C) HL-60 leukemic cells were...treated with solvent ( DMSO ), 50 or 100 μM of each indicated analog for 24 h, followed by trypan blue exclusion assay. The numbers given are

  12. Are new antibiotics better than beta-lactams for non-critical inpatients with community-acquired pneumonia?

    Directory of Open Access Journals (Sweden)

    Tomás Reyes B.

    2016-09-01

    Full Text Available Resumen El tratamiento de la neumonía adquirida en la comunidad en el adulto inmunocompetente es empírico, siendo tradicionalmente los antibióticos betalactámicos la terapia de primera línea. Se ha postulado que nuevos antibióticos podrían ser más efectivos, pero hasta el momento este planteamiento no ha sido corroborado por la evidencia disponible y su uso podría asociarse a mayor costo, aumento de la resistencia bacteriana y otros efectos adversos. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas realizadas en 30 bases de datos, identificamos seis revisiones sistemáticas que en conjunto incluyen 36 estudios aleatorizados pertinentes a la pregunta. Realizamos un metanálisis y tablas de resumen de los resultados utilizando el método GRADE. Concluimos que los nuevos antibióticos no son mejores que los antibióticos betalactámicos en pacientes adultos hospitalizados con neumonía no severa en cuanto a riesgo de fracaso clínico o efectos adversos.

  13. Thioridazine potentiates the effect of a beta-lactam antibiotic against Staphylococcus aureus independently of mecA expression

    DEFF Research Database (Denmark)

    Poulsen, Marianne Østergaard; Jacobsen, Kirstine; Bonde, Mette

    2013-01-01

    The neuroleptic antipsychotic derivate thioridazine has been shown to increase the susceptibility of a methicillin-resistant Staphylococcus aureus (MRSA) isolate towards dicloxacillin. The aim of this study was to investigate the combinatorial effect of the two drugs on a broad selection of staph......The neuroleptic antipsychotic derivate thioridazine has been shown to increase the susceptibility of a methicillin-resistant Staphylococcus aureus (MRSA) isolate towards dicloxacillin. The aim of this study was to investigate the combinatorial effect of the two drugs on a broad selection...... of staphylococcal strains by analyzing a large collection of MRSA strains carrying different types of SCCmec, as well as MSSA strains. Transcription and translation of the resistance marker PBP2a encoded by mecA within the SCCmec cassette were analyzed by primer extension and western blotting. We observed increased...... susceptibility to dicloxacillin in the presence of thioridazine in all tested MRSA isolates. In contrast to previously published results, the synergistic effect was also applicable to methicillin-susceptible S. aureus (MSSA). We conclude that the combination of dicloxacillin and thioridazine potentiates...

  14. Beta-lactam degradation catalysed by Cd2+ ion in methanol.

    Science.gov (United States)

    Martínez, J H; Navarro, P G; Garcia, A A; de las Parras, P J

    1999-08-01

    Kinetic schemes are established for degradation catalysed by Cd2+ ions in methanolic medium for penicillin G, penicillin V and cephalothin, a cephalosporin. Methanolysis of penicillin V and cephalothin occurs with the formation of a single substrate-metal ion intermediate complex, SM, while degradation of penicillin G occurs with the initial formation of two complexes with different stoichiometry, SM and S2M. In each case. degradation is of first order with respect to SM with rate constant values equal to 0.079 min(-1), 0.120 min(-1) and 0.166 min(-1) at 20, 25 and 30 degrees C, respectively, for penicillin G; 0.061 min(-1) at 20 degrees C for penicillin V; and 2.0 x 10(-3) min(-1) at 20 degrees C for cephalothin. Activation energy for the decomposition process of the SM intermediate for penicillin G was calculated to be about 5.5 x 10(4) J/mol. Equilibrium constant values between SM compound and S2M at 20 degrees C (77.1 l/mol), 25 degrees C (45.3 l/mol) and at 30 degrees C (25.7 l/mol) were also calculated as well as the normal enthalpy of this equilibrium. With respect to the reaction products there is evidence that Cd2+ becomes part of their structure, forming complexes between Cd2+ and the product resulting from antibiotic methanolysis (L). Some characteristics of these complexes are discussed.

  15. Plasmid-mediated AmpC-type beta-lactamase isolated from Klebsiella pneumoniae confers resistance to broad-spectrum beta-lactams, including moxalactam.

    Science.gov (United States)

    Horii, T; Arakawa, Y; Ohta, M; Ichiyama, S; Wacharotayankun, R; Kato, N

    1993-01-01

    Klebsiella pneumoniae NU2936 was isolated from a patient and was found to produce a plasmid-encoded beta-lactamase (MOX-1) which conferred resistance to broad spectrum beta-lactams, including moxalactam, flomoxef, ceftizoxime, cefotaxime, and ceftazidime. Resistance could be transferred from K. pneumoniae NU2936 to Escherichia coli CSH2 by conjugation with a transfer frequency of 5 x 10(-7). The structural gene of MOX-1 (blaMOX-1) was cloned and expressed in E. coli HB101. The MIC of moxalactam for E. coli HB101 producing MOX-1 was > 512 micrograms/ml. The apparent molecular mass and pI of this enzyme were calculated to be 38 kDa and 8.9, respectively. Hg2+ and Cu2+ failed to block enzyme activity, and the presence of EDTA in the reaction buffer did not reduce the enzyme activity. However, clavulanate and cloxacillin, serine beta-lactamase inhibitors, inhibited the enzyme activity competitively (Kis = 5.60 and 0.35 microM, respectively). The kinetic study of MOX-1 suggested that it effectively hydrolyzed broad-spectrum beta-lactams. A hybridization study confirmed that blaMOX-1 is encoded on a large resident plasmid (pRMOX1; 180 kb) of strain NU2936. By deletion analysis, the functional region was localized within a 1.2-kb region of the plasmid. By amino acid sequencing, 18 of 33 amino acid residues at the N terminus of MOX-1 were found to be identical to those of Pseudomonas aeruginosa AmpC. These findings suggest that MOX-1 is a plasmid-mediated AmpC-type beta-lactamase that provides enteric bacteria resistance to broad-spectrum beta-lactams, including moxalactam. Images PMID:8517725

  16. Inoculum effect of high concentrations of methicillin-susceptible Staphylococcus aureus on the efficacy of cefazolin and other beta-lactams.

    Science.gov (United States)

    Saeki, Masachika; Shinagawa, Masaaki; Yakuwa, Yuki; Nirasawa, Shinya; Sato, Yuki; Yanagihara, Nozomi; Takahashi, Satoshi

    2018-03-01

    The existence of a cefazolin inoculum effect (InE) of methicillin-susceptible Staphylococcus aureus (MSSA), which is speculated to be a reason for cefazolin treatment failure in MSSA infections, is controversial. In Japan, although cefazolin is one of the therapeutic choices for patients with MSSA infection, there are few reports of this effect. Additionally, the association between InE and blaZ type in beta-lactams other than cefazolin has not been well documented. In this study, we confirmed an MSSA InE in several beta-lactams, including cefazolin, and its relationship with blaZ, using 52 MSSA isolates from blood cultures. Three isolates (5.8%) that possessed type A blaZ showed a pronounced cefazolin InE. Five isolates (9.6%) showed pronounced InE with sulbactam/ampicillin; four isolates had type C blaZ and one had type A blaZ. However, we confirmed InE in MSSA isolates with blaZ not only type A and C but also B and D. For cefotaxime, ceftriaxone, imipenem, and meropenem, regardless of the presence of blaZ, we did not observe a significant increase in MICs at a high inoculum of MSSA. Hence, our results suggest that the above four beta-lactams are good alternatives to cefazolin if InE leads to treatment failure in a patient. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  17. The Effect of Antioxidants on Antibiotic Sensitivity of Bacteria

    OpenAIRE

    Azade ATTAR; Akif İ. QURBANOV

    2007-01-01

    Objective: The effect of different concentrations of antioxidants (ascorbic acid, emoxipin, tocopherol acetate and ionol) on antibiotic sensitivity of bacteria was studied. Method: Bacteria belong to different respiration types: Pseudomonas aeruginosa as aerobe and Escherichia coli as facultative anaerobe were used. Antibiotic sensitivity of microorganisms was determined as minimum inhibitory concentration (MIC) by dilution test. Results: Different concentrations of antioxidants increased the...

  18. Antibiotics sensitivity profile of proteus species associated with ...

    African Journals Online (AJOL)

    Antibiotics sensitivity profile of proteus species associated with specific infections at University of Ilorin Teaching Hospital, Ilorin. ... Results of the antimicrobial sensitivity testing showed that Imipenem and Piperacillin antibiotics were the most effective against Proteus sppwith each having 100%, followed by Ceftazidime ...

  19. Antibiotic Sensitivity Patterns of Aerobic Bacterial Agents in Post ...

    African Journals Online (AJOL)

    Antibiotic Sensitivity Patterns of Aerobic Bacterial Agents in Post-Surgical ... those commonly used to treat orofacial infections were tested for sensitivity against the ... were the augmented Penicillins and newer generations Cephalosporins.

  20. Gamma irradiation increase the sensitivity of Salmonella to antibiotics

    International Nuclear Information System (INIS)

    Ben Miloud, Najla; Barkallah, Insaf

    2008-01-01

    In order to study the effect of ionizing radiation on the resistance of Salmonella to antibiotics, four strains of Salmonella were isolated from foods, The different strains used in the present study are (S. Hadar isolate 287, S. Hadar isolate 63, S. Cerro isolate 291, S. Zanzibar isolate 1103), antibiogram analyses were made to test the in vitro-sensitivity of irradiated Salmonella isolates to different antibiotics.The analyse of Control and exposed antibiograms showed that gamma radiation have increased the sensitivity of Salmonella isolates to Cefalotin, Chloramphenicol, Nalidixic acid, Spiramycin and Gentamycin excepted S. Hadar isolate 287 that was resistant to Cefalotin and became sensitive after irradiation. Statistical analyses showed that the effect of different irradiation dose treatment on the antibiotic sensitivity is increasingly significant. The irradiation didn't induce modifications of the sensitivity to other antibiotics,probably because of their nature, of their penetration mode inside the cell or their action way

  1. Genetic markers associated with resistance to beta-lactam and quinolone antimicrobials in non-typhoidal Salmonella isolates from humans and animals in central Ethiopia

    Directory of Open Access Journals (Sweden)

    Tadesse Eguale

    2017-01-01

    Full Text Available Abstract Background Beta-lactam and quinolone antimicrobials are commonly used for treatment of infections caused by non-typhoidal Salmonella (NTS and other pathogens. Resistance to these classes of antimicrobials has increased significantly in the recent years. However, little is known on the genetic basis of resistance to these drugs in Salmonella isolates from Ethiopia. Methods Salmonella isolates with reduced susceptibility to beta-lactams (n = 43 were tested for genes encoding for beta-lactamase enzymes, and those resistant to quinolones (n = 29 for mutations in the quinolone resistance determining region (QRDR as well as plasmid mediated quinolone resistance (PMQR genes using PCR and sequencing. Results Beta-lactamase genes (bla were detected in 34 (79.1% of the isolates. The dominant bla gene was blaTEM, recovered from 33 (76.7% of the isolates, majority being TEM-1 (24, 72.7% followed by TEM-57, (10, 30.3%. The blaOXA-10 and blaCTX-M-15 were detected only in a single S. Concord human isolate. Double substitutions in gyrA (Ser83-Phe + Asp87-Gly as well as parC (Thr57-Ser + Ser80-Ile subunits of the quinolone resistance determining region (QRDR were detected in all S. Kentucky isolates with high level resistance to both nalidixic acid and ciprofloxacin. Single amino acid substitutions, Ser83-Phe (n = 4 and Ser83-Tyr (n = 1 were also detected in the gyrA gene. An isolate of S. Miami susceptible to nalidixic acid but intermediately resistant to ciprofloxacin had Thr57-Ser and an additional novel mutation (Tyr83-Phe in the parC gene. Plasmid mediated quinolone resistance (PMQR genes investigated were not detected in any of the isolates. In some isolates with decreased susceptibility to ciprofloxacin and/or nalidixic acid, no mutations in QRDR or PMQR genes were detected. Over half of the quinolone resistant isolates in the current study 17 (58.6% were also resistant to at least one of the beta-lactam antimicrobials

  2. Comparison of beta-lactam regimens for the treatment of gram-negative pulmonary infections in the intensive care unit based on pharmacokinetics/pharmacodynamics.

    Science.gov (United States)

    Burgess, David S; Frei, Christopher R

    2005-11-01

    This study utilized pharmacokinetics/pharmacodynamics to compare beta-lactam regimens for the empirical and definitive treatment of gram-negative pulmonary infections in the ICU. Susceptibility data were extracted from the 2002 Intensive Care Unit Surveillance System (ISS) and pharmacokinetic parameters were obtained from published human studies. Monte Carlo simulation was used to model the free percent time above the MIC (free %T > MIC) for 18 beta-lactam regimens against all gram-negative isolates, Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii. The cumulative fraction of response (CFR) was determined for bacteriostatic and bactericidal targets (free %T > MIC): penicillins (> or = 30/50%), cephalosporins/monobactams (> or = 40/70%) and carbapenems (> or = 20/40%). The 2002 ISS database contained MICs for 2408 gram-negative isolates including 1430 Enterobacteriaceae, 799 P. aeruginosa, and 179 A. baumannii. Imipenem had the highest percentage susceptible for all gram-negatives, Enterobacteriaceae and A. baumannii, while piperacillin/tazobactam had the highest percentage susceptible for P. aeruginosa. For empirical therapy, imipenem 0.5 g every 6 h, cefepime 2 g every 8 h and ceftazidime 2 g every 8 h demonstrated the highest CFR. For definitive therapy, imipenem 0.5 g every 6 h, ertapenem 1 g daily and cefepime 2 g every 8 h, cefepime 1 g every 8 h and cefepime 1 g every 12 h had the highest bactericidal CFR against Enterobacteriaceae; ceftazidime 2 g every 8 h, cefepime 2 g every 8 h, piperacillin/tazobactam 3.375 g every 4 h, ceftazidime 1 g every 8 h and aztreonam 1 g every 8 h against P. aeruginosa; and imipenem 0.5 g every 6 h, ticarcillin/clavulanate 3.1 g every 4 h, ceftazidime 2 g every 8 h, cefepime 2 g every 8 h and ticarcillin/clavulanate 3.1 g every 6 h against A. baumannii. Based on pharmacokinetics/pharmacodynamics, imipenem 0.5 g every 6 h, cefepime 2 g every 8 h and ceftazidime 2 g every 8 h should be the preferred beta-lactam

  3. Alergia a beta-lactâmicos na clínica pediátrica: uma abordagem prática Allergy to beta-lactams in pediatrics: a practical approach

    Directory of Open Access Journals (Sweden)

    Nelson A. Rosário

    2006-11-01

    Full Text Available OBJETIVO: Apresentar uma abordagem prática ao diagnóstico e conduta na alergia a antibióticos beta-lactâmicos. FONTES DOS DADOS: Periódicos da área de alergia indexados nas bases MEDLINE e LILACS, além de estudos e textos clássicos que tratam do tema. SÍNTESE DOS DADOS: A alergia à penicilina é relatada com freqüência, em muitos casos resultando na exclusão desse medicamento do arsenal terapêutico. Cerca de 10% dos relatos de alergia a drogas são confirmados. As manifestações clínicas decorrentes da reação alérgica à penicilina são bastante amplas, destacando-se os quadros cutâneos. Os quatro mecanismos de hipersensibilidade de Gell & Coombs estão envolvidos nas reações alérgicas. A penicilina é degradada em determinante maior (95% dos produtos e em determinantes menores (5% dos produtos. As reações imediatas, mediadas por IgE, e que determinam quadros de anafilaxia, estão relacionadas aos determinantes menores em 95% dos casos. A hipersensibilidade a esses produtos pode ser avaliada através de testes cutâneos realizados com os determinantes maior e menores, permitindo, assim, evitar o choque anafilático em indivíduos alérgicos. O texto ressalta conhecimentos básicos sobre a alergia à penicilina, propiciando um diagnóstico mais adequado desse evento e a conduta em casos de suspeita de alergia a beta-lactâmicos. CONCLUSÃO: O diagnóstico de alergia à penicilina tem sido feito de forma inadequada, resultando em sua exclusão do arsenal terapêutico. O melhor reconhecimento dessas condições permitirá o uso da penicilina com diminuição dos riscos decorrentes da hipersensibilidade.OBJECTIVE: To present a practical approach to the diagnosis and management of allergy to beta-lactam antibiotics. SOURCES: Allergy journals indexed in MEDLINE and LILACS, as well as seminal studies and texts. SUMMARY OF THE FINDINGS: Allergy to penicillin is commonly reported. In many cases, this results in the decision not

  4. Prophylaxis for infective endocarditis: antibiotic sensitivity of dental plaque.

    OpenAIRE

    MacFarlane, T W; McGowan, D A; Hunter, K; MacKenzie, D

    1983-01-01

    The antibiotic sensitivity pattern of bacteria isolated from bacteraemia after dental extraction was compared with that of bacteria isolated from dental plaque samples from the same patient. The results supported the current practice of using penicillin and erythromycin empirically for prophylaxis. The prediction of the most appropriate antibiotic for prophylaxis using dental plaque samples was most accurate when the minimum inhibitory concentration (MIC) of plaque isolates were used. It appe...

  5. Functional characterization of the oxaloacetase encoding gene and elimination of oxalate formation in the beta-lactam producer Penicillium chrysogenum

    NARCIS (Netherlands)

    Gombert, A. K.; Veiga, T.; Puig-Martinez, M.; Lamboo, F.; Nijland, J. G.; Driessen, A. J. M.; Pronk, J. T.; Daran, J. M.

    Penicillium chrysogenum is widely used as an industrial antibiotic producer, in particular in the synthesis of g-lactam antibiotics such as penicillins and cephalosporins. In industrial processes, oxalic acid formation leads to reduced product yields. Moreover, precipitation of calcium oxalate

  6. Sensitivity of some local isolates of Mycoplasma gallisepticum against antibiotics

    Directory of Open Access Journals (Sweden)

    Sutiastuti Wahyuwardani

    1998-03-01

    Full Text Available Sensitivity of five local isolates ofMycoplasma gallisepticum (MG strain and two standard MG isolates obtained from Australia were tested against antibiotics of oxytetracycline, doxycycline, erythromycin, bacitracin, vancomycin, methicillin and penicillin using antibiogram disc method. The result showed that one, 2 and 3 local MG isolates were resistent to doxycycline, erythromycin and oxytetracycline respectively . MG isolate of ADA7 from Australia was found to be resistent to all antibiotics tested. None ofthe local MG isolates were sensitive against bacitracin, vancomycin, methicillin and penicillin.

  7. 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.

  8. The prevalence of nosocomial infections caused by Enterobacter cloacae and antibiotic resistant patterns in samples isolated from patients in two hospitals in Tehran

    Directory of Open Access Journals (Sweden)

    Rahbar M

    2012-06-01

    Conclusion: This study clearly showed the high prevalence of resistance to broad-spectrum beta-lactam antibiotics in the isolated E. cloacae among which 5% were multi drug resistant. All the isolated E. cloacae were susceptible to Colistin. These results can be alarming for physicians treating resistant E. cloacae infections, especially extended-spectrum beta-lactamase producing species.

  9. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical

    African Journals Online (AJOL)

    raoul

    2011-01-26

    Jan 26, 2011 ... Key words: Staphylococcus aureus, antibiotic sensitivity, Nigeria, Kano ... infection have an increased colonization risks [8]. ... confirmed Staphylococcus aureus isolates was prepared in peptone water to ... 5 g methicillin discs (oxoid, USA) were aseptically placed on the surface of the inoculated plates and ...

  10. Antibiotic Sensitivity Profile of Escherichia coli Isolated from Poultry ...

    African Journals Online (AJOL)

    A cross sectional study involving 300 cloaca swabs from apparently healthy birds from 8 small-medium scale poultry farms in Ibadan Oyo State was carried out. A total of 201 (67%) Escherichia coli isolates were recovered from the birds and they were subjected to in-vitro antibiotic sensitivity test by agar gel diffusion method.

  11. Antibiotic sensitivities of common bacterial pathogens in urinary tract ...

    African Journals Online (AJOL)

    Of the total isolates 71.5% were Gram negatives. Sensitivity tested against ten antibiotics showed that resistance was common, and the effectiveness of tetracycline, ampicillin, co-trimoxazole, chloramphenicol and penicillin was under 50.0%. The resistance rate was 71.5%, 62.2%, and 62.2%, 54.7% and 40.8%, respectively ...

  12. Bacterial Isolates andAntibiotic Sensitivity in Community Acquired ...

    African Journals Online (AJOL)

    Objective: The objective of the studywas to determine bacterial causes of community acquired pneumonia and their antibiotic sensitivity pattern amongst patients admitted intomedicalwards inAminu Kano Teaching Hospital, Kano, Nigeria Methods: The study incorporated patients aged fifteen years and above admitted into ...

  13. Penicillin sensitivity among children without a positive history for penicillin allergy.

    Science.gov (United States)

    Cetinkaya, Feyzullah; Cag, Yakup

    2004-06-01

    To establish the prevalence of positive penicillin skin tests among outpatients without any drug reaction history. Skin testing was performed in 147 children (aged 6-13 years) who had had received a penicillin preparation at least three times in the last 12 months without any allergic reaction. Before testing, detailed pediatric and allergy history were learned and then all children were tested with benzyl penicilloyl polylysin (PPL) and mixture of minor antigenic determinants. The test procedures were made epidermally and intradermally subsequently in every subject. The overall frequency of positive skin reactions to penicillin antigens was 10.2%. A mild systemic reaction was observed in one of the children during testing with PPL. We concluded that frequent use of penicillin and other beta-lactam antibiotics leads to sensitization of children in our study population despite these children seem to be asymptomatic during testing time. Copyright 2004 Blackwell Munksgaard

  14. Sensitizing pathogens to antibiotics using the CRISPR-Cas system.

    Science.gov (United States)

    Goren, Moran; Yosef, Ido; Qimron, Udi

    2017-01-01

    The extensive use of antibiotics over the last century has resulted in a significant artificial selection pressure for antibiotic-resistant pathogens to evolve. Various strategies to fight these pathogens have been introduced including new antibiotics, naturally-derived enzymes/peptides that specifically target pathogens and bacteriophages that lyse these pathogens. A new tool has recently been introduced in the fight against drug-resistant pathogens-the prokaryotic defense mechanism-clustered regularly interspaced short palindromic repeats-CRISPR associated (CRISPR-Cas) system. The CRISPR-Cas system acts as a nuclease that can be guided to cleave any target DNA, allowing sophisticated, yet feasible, manipulations of pathogens. Here, we review pioneering studies that use the CRISPR-Cas system to specifically edit bacterial populations, eliminate their resistance genes and combine these two strategies in order to produce an artificial selection pressure for antibiotic-sensitive pathogens. We suggest that intelligent design of this system, along with efficient delivery tools into pathogens, may significantly reduce the threat of antibiotic-resistant pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. A possible role for acetylated intermediates in diaminopimelate and tabtoxinine-beta-lactam biosynthesis in Pseudomonas syringae pv. tabaci BR2.024.

    Science.gov (United States)

    Liu, L; Shaw, P D

    1997-01-01

    The deduced product of an open reading frame (ORF3) located in the tabtoxinine-beta-lactam (T beta L) biosynthetic region of Pseudomonas syringae pv. tabaci BR2.024 (BR2.024) has significant sequence homology to the dapD products of other bacteria. dapD encodes L-2,3,4,5-tetrahydrodipicolinate succinyl coenzyme A succinyltransferase (THDPA-ST), an enzyme in the diaminopimelate (DAP) and lysine biosynthetic pathway. Complementation studies, in vitro transcription-translation experiments, and enzymatic assays indicated that ORF3 encodes a product with THDPA-ST activity in Escherichia coli dapD mutant beta 274. However, a BR2.024 mutant with an insert in ORF3 was prototrophic, and only basal THDPA-ST activity was detected in extracts of both parent and mutant. This finding suggested that ORF3 was not required for DAP biosynthesis and that it did not encode a product with THDPA-ST activity. The results of enzymatic studies, indicating that BR2.024 uses acetylated intermediates for DAP biosynthesis, are consistent with the hypothesis that BR2.024 does not need THDPA-ST for DAP biosynthesis. The ORF3 mutant produced reduced levels of tabtoxin, indicating that ORF3 may have a role in T beta L biosynthesis. We have named the gene tabB and have proposed a possible function for the gene product. PMID:9294453

  16. Dissemination and genetic support of broad-spectrum beta-lactam-resistant Escherichia coli strain isolated from two Tunisian hospitals during 2004-2012.

    Science.gov (United States)

    Ayari, Khaoula; Bourouis, Amel; Chihi, Hela; Mahrouki, Sihem; Naas, Thierry; Belhadj, Omrane

    2017-06-01

    The dissemination of extended-spectrum β-lactamase (ESBL)-producing bacteria presented a great concern worldwide. Gram-negative organisms such as Escherichia coli and Klebsiella pneumoniae are the most frequently isolated pathogens responsible for nosocomial infections. The aim of this study was to investigate and to follow the emergence of resistance and the characterization of Extended-Spectrum Beta-Lactamases (ESBL) among broad-spectrum beta-lactam- Escherichia coli clinical isolates recovered from the military hospital and Habib Thameur hospital in Tunisia. A total of 113 E.coli isolates obtained during the period 2004 through 2012 showed a significant degree of multi-resistance. Among these strains, the double-disk synergy test confirmed the ESBL phenotype in 46 isolates. These included 32(70%) strains from Hospital A and 14(30%) from Hospital B. The ESBL was identified as CTX-M-15. The ESBL resistance was transferred by a 60 kb plasmid CTXM-15-producing isolates were unrelated according to the PFGE analysis and characterization of the regions surrounding the blaCTX-M-15 showed the ISEcp1 elements located in the upstream region of the bla gene and 20 of them truncated by IS26. ESBL producing E. coli strains are a serious threat in the community in Tunisia and we should take into consideration any possible spread of such epidemiological resistance.

  17. Transport of cefodizime, a novel third generation cephalosporin antibiotic, in isolated rat choroid plexus

    International Nuclear Information System (INIS)

    Nohjoh, T.; Suzuki, H.; Sawada, Y.; Sugiyama, Y.; Iga, T.; Hanano, M.

    1989-01-01

    To characterize the transport system by which cephalosporin antibiotics are accumulated by the choroid plexus, kinetic analysis of cefodizime transport was performed. Accumulation of cefodizime was against an electrochemical potential gradient via a saturable process (Km = 470 microM, Vmax = 174 nmol/ml of tissue per min) that was inhibited by metabolic inhibitors (KCN and 2,4-dinitrophenol), hypothermia, a sulfhydryl reagent (p-hydroxymer-curibenzoic acid) and anion transport inhibitors (probenecid and 4,4'-diisothiocyanostilbene -2,2'-disulfonic acid). Accumulation of cefodizime was inhibited competitively by benzylpenicillin with an inhibition constant of aproximately 100 microM. Cefodizime inhibited competitively the accumulation of benzylpenicillin with an inhibition constant of approximately 500 microM. Kinetic analysis using 16 kinds of beta-lactam antibiotics also supported the view (1) that the transport system of cefodizime is shared by benzylpenicillin and (2) that these beta-lactam antibiotics are transported via a common transport system. These findings indicate that the major transport system of cephalosporin antibiotics in the rat choroid plexus is via a carrier-mediated active anion transport process. The affinity of beta-lactam antibiotics for this transport system in the choroid plexus may be a major factor in determining their pharmacokinetics in the cerebrospinal fluid

  18. Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria.

    Science.gov (United States)

    Yosef, Ido; Manor, Miriam; Kiro, Ruth; Qimron, Udi

    2015-06-09

    The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones.

  19. Use of antibiotics in children

    DEFF Research Database (Denmark)

    Pottegård, Anton; Broe, A.; Aabenhus, R.

    2015-01-01

    Background: We aimed to describe the use of systemic antibiotics among children in Denmark. Methods: National data on drug use in Denmark were extracted from the Danish National Prescription Database. We used prescription data for all children in Denmark aged 0 to 11 years from January 1, 2000...... to December 31, 2012. Results: We obtained data on 5,884,301 prescriptions for systemic antibiotics issued to 1,206,107 children. The most used single substances were phenoxymethylpenicillin (45%), amoxicillin (34%) and erythromycin (6%). The highest incidence rate of antibiotic treatment episodes......-1. There was little evidence of heavy users. Conclusion: Prescribing rate of antibiotics to children in Denmark remained stable at a high level from 2000 to 2012. An increase in the use of broad-spectrum beta-lactam penicillin was noted, but otherwise the prescribing pattern adhered well to National guidelines...

  20. Metabolic regulation of mycobacterial growth and antibiotic sensitivity.

    Directory of Open Access Journals (Sweden)

    Seung-Hun Baek

    2011-05-01

    Full Text Available Treatment of chronic bacterial infections, such as tuberculosis (TB, requires a remarkably long course of therapy, despite the availability of drugs that are rapidly bacteriocidal in vitro. This observation has long been attributed to the presence of bacterial populations in the host that are "drug-tolerant" because of their slow replication and low rate of metabolism. However, both the physiologic state of these hypothetical drug-tolerant populations and the bacterial pathways that regulate growth and metabolism in vivo remain obscure. Here we demonstrate that diverse growth-limiting stresses trigger a common signal transduction pathway in Mycobacterium tuberculosis that leads to the induction of triglyceride synthesis. This pathway plays a causal role in reducing growth and antibiotic efficacy by redirecting cellular carbon fluxes away from the tricarboxylic acid cycle. Mutants in which this metabolic switch is disrupted are unable to arrest their growth in response to stress and remain sensitive to antibiotics during infection. Thus, this regulatory pathway contributes to antibiotic tolerance in vivo, and its modulation may represent a novel strategy for accelerating TB treatment.

  1. Recognition of peptidoglycan and beta-lactam antibiotics by the extracellular domain of the Ser/Thr protein kinase StkP from Streptococcus pneumoniae

    Czech Academy of Sciences Publication Activity Database

    Maestro, B.; Nováková, Linda; Hesek, D.; Lee, M.; Leyva, E.; Mobashery, S.; Sanz, J.M.; Branny, Pavel

    2011-01-01

    Roč. 585, č. 2 (2011), s. 357-363 ISSN 0014-5793 R&D Projects: GA ČR GP204/07/P082; GA ČR GA204/08/0783; GA AV ČR IAA600200801 Institutional research plan: CEZ:AV0Z50200510 Keywords : Signal transduction * Penicillin-binding protein and Ser/Thr protein kinase-associated domain * Peptidoglycan Subject RIV: CE - Biochemistry Impact factor: 3.538, year: 2011

  2. Meropenem in cystic fibrosis patients infected with resistant Pseudomonas aeruginosa or Burkholderia cepacia and with hypersensitivity to beta-lactam antibiotics

    DEFF Research Database (Denmark)

    Ciofu, Oana; Jensen, Tim; Pressler, Tacjana

    1996-01-01

    in pulmonary function (as a percentage of the predictive values) was 5.6% for FEV1 (forced expiratory volume in the first second) and 8.6% for FVC (forced vital capacity). C-reactive protein and erythrocyte sedimentation rate (ESR) and leukocyte count decreased significantly. In courses administered...... for chronic infection with B. cepacia the post treatment FEV1 and FVC values were higher than the pre-treatment values, and all the inflammatory parameters decreased. The geometric means of minimal inhibitory concentration (MICs) (microg/mL) for P. aeruginosa (B. cepacia) were: tobramycin 6 (59......), ciprofloxacin 1.2 (9.7), piperacillin 49 (16.3), ceftazidime 26 (23), aztreonam 26 (35), imipenem 6.4 (not determined) and meropenem 5.1 (4.8). No statistically significant increase in the MICs of meropenem for either pathogen occurred during therapy. Of the 124 courses, 115 were tolerated without any clinical...

  3. MICROORGANISMS ANTIBIOTIC SENSITIVITY DETERMINATION IN URINARY TRACT INFECTIONS

    Directory of Open Access Journals (Sweden)

    Shapovalova O.V.

    2016-06-01

    Full Text Available Introduction. Nowadays Urinary tract infections (UTI are considered to be the most common bacterial infections. Escherichia coli is the most frequently uropathogen. Other microorganisms of the genera Enterococcus, Klebsiella, Enterobacter, Proteus, Morganella, Citrobacter, Serratia, Pseudomonas, Streptococcus, Staphylococcus, Candida are also isolated with variable frequency. In recent years there has been a decreasing tendency of the causative agents of UTI sensitivity to various antibiotics, which causes growth of an inefficiency treatment risk. In connection with the above the investigations were carried out with the purpose to identify the actual causative agents of bacteriuria and their sensitivity to antibiotics and antifungal drugs. Materials and methods. Bacteriological examination of urine was performed at 42 patients of SI "Sytenko Institute of Spine and Joint Pathology, AMS of Ukraine" clinic. The bacteriological method for determining the number of bacteria in the test material, cultural and bacterioscopic methods for identifying microorganisms and disk-diffusion method for sensitivity of microorganisms to antibiotics determining were used. The clinical material for the study was an average portion of the morning urine or urine collected by catheter. The biological material collection and bacteriological examination was carried by quantitative method, the isolated microorganisms identification and their sensitivity to antibiotics determining was performed by standard methods in accordance with current guidelines. We used the following antibiotics group to determine the microorganisms sensitivity: penicillin, cephalosporin, karbapenems, tetracyclines, aminoglycoside, fluoroquinolones, oxazolidinones, macrolides, lincosamides, glycopeptides, antifungal antibiotics. Results and discussion. During the biological material study 55 isolates of bacterial and fungal pathogens were obtained. The microorganisms’ concentration in urine was in

  4. Diagnosis and Antibiotic Resistance Distribution in Children with Urinary Tract Infection: A Single Center Experience

    Directory of Open Access Journals (Sweden)

    Rahime Renda

    2018-01-01

    Full Text Available Background: Urinary tract infection is a common disease in childhood. The aim of this study was to determine the diagnostic performance of urinary analysis, assess the role of urine culture in determining its necessity and evaluate etiologic agents and antimicrobial resistance patterns in children with urinary tract infection.Methods: Our study was made by evaluating the patients who applied to the Antalya Research and Training Hospital- Turkey, between 2015 and 2017. A total 237 urine analysis and urine culture were retrospectively analyzed. Culture results were taken a reference for microscopic and chemical examination of urine and diagnostic accuracy of the test parameters, and the performance of urine analysis were calculated. The culture and antibiogram results were examined and antibiotic resistance with infectious agents frequency was evaluated.Results: The 42.4% of culture negative samples showed leukocyte esterase, nitrite, bacterial and leukocyte counts, which are indicative of infection in urine analysis, were found in normal range. The highest sensitivity (90% was in the presence of leucocyte esterase and bacteria, while the highest specificity (99.4% was in the presence of nitrite alone or with other components (leucocyte or leucocyte esterase. The highest antibiotic resistance was found in beta lactam antibiotics. The lowest antibiotic resistance was detected in the carbapenem followed by fluoroquinolone group antibiotics.Conclusion: Microscopic and chemical examination of urine analysis can give us information about urine culture requirement. The observation of increasing overall resistance to antibiotics authorize further studies that lead to new recommendations to antibiotic use in children and adolescents.

  5. A radiotracer study of the sensitivity of bacteria to antibiotics

    International Nuclear Information System (INIS)

    Nagy, E.J.

    1975-01-01

    In the developed measuring apparatus the test bacterium E.coli was dissolved in 25 ml of the synthetic medium M9 (pH=7.0) and 2 μCi of D-glucose- 14 C (80 μg of glucose) was added to the solution. The test material was incubated at 37+-0.2 degC. In closed system the quantity of developing 14 CO 2 have been proportional to the multiplication rate of bacterium. The radioactive CO 2 have been absorbed in the box containing the liquid scintillation material. The absorption capacity of the toluene-base scintillation liquid was increased by adding diethanolamine (pH=10) and the multiplication was promoted by constant mixing. The sensitivity of the given bacterium to antibiotics like Penicillin G, Tetracyclin, Ampicillin, Polymycin B can be given in 60-120 min. (K.A.)

  6. Reversing bacterial resistance to antibiotics by phage-mediated delivery of dominant sensitive genes.

    Science.gov (United States)

    Edgar, Rotem; Friedman, Nir; Molshanski-Mor, Shahar; Qimron, Udi

    2012-02-01

    Pathogen resistance to antibiotics is a rapidly growing problem, leading to an urgent need for novel antimicrobial agents. Unfortunately, development of new antibiotics faces numerous obstacles, and a method that resensitizes pathogens to approved antibiotics therefore holds key advantages. We present a proof of principle for a system that restores antibiotic efficiency by reversing pathogen resistance. This system uses temperate phages to introduce, by lysogenization, the genes rpsL and gyrA conferring sensitivity in a dominant fashion to two antibiotics, streptomycin and nalidixic acid, respectively. Unique selective pressure is generated to enrich for bacteria that harbor the phages carrying the sensitizing constructs. This selection pressure is based on a toxic compound, tellurite, and therefore does not forfeit any antibiotic for the sensitization procedure. We further demonstrate a possible way of reducing undesirable recombination events by synthesizing dominant sensitive genes with major barriers to homologous recombination. Such synthesis does not significantly reduce the gene's sensitization ability. Unlike conventional bacteriophage therapy, the system does not rely on the phage's ability to kill pathogens in the infected host, but instead, on its ability to deliver genetic constructs into the bacteria and thus render them sensitive to antibiotics prior to host infection. We believe that transfer of the sensitizing cassette by the constructed phage will significantly enrich for antibiotic-treatable pathogens on hospital surfaces. Broad usage of the proposed system, in contrast to antibiotics and phage therapy, will potentially change the nature of nosocomial infections toward being more susceptible to antibiotics rather than more resistant.

  7. Antibiotic sensitivity of Enterobacteriaceae at a tertiary care center in India

    Directory of Open Access Journals (Sweden)

    Summaiya Mulla

    2011-01-01

    Full Text Available Aims and Objectives: It has been observed that various microorganisms are acquiring resistance to most of the available potent antibiotics; hence, there is a need for every hospital to follow the use of antibiotics according to antibiotic sensitivity pattern in that particular hospital or geographical area. It has been reported that Enterobacteriaceae group of microorganisms are increasingly acquiring resistance to many antibiotics and this resistance varies geographically. As there is a short of recent data with respect to Indian hospital, this particular study was designed with the aim of establishing sensitivity pattern of Enterobacteriaceae group of microorganisms to various antibiotics. Materials and Methods: Data of antibiotic sensitivity from December 2010 to April 2011 of different Enterobacteriaceae was taken from the Department of Microbiology, Govt. Medical College, Surat. Sensitivity of different Enterobacteriaceae was shown as using descriptive statistics. Results: E. coli (55.6% and Klebsiella (31.2% were the most frequent bacteria isolated. Enterobacteriaceae were very less sensitive to amoxicillin + clavulanic acid (13.7%, chloramphenicol (7.6%, cefoperazone (14.4%, cefixime (15.7%, and cefuroxime (17.6. Sensitivity to aztreonam was 32.7%. Sensitivity to carbapenem group of drugs included in this study, i.e., meropenem was 69.8%. Highest sensitivity was shown for ceftazidime (74.1%. E. coli is more sensitive to meropenem as compared with Klebsiella. Conclusion: Sensitivity of Enterobacteriaceae group of microorganisms to known antibiotics is decreasing. Decreased sensitivity to carbapenem group of antibiotics is a matter of concern.

  8. The role of outer membrane in Serratia marcescens intrinsic resistance to antibiotics.

    Science.gov (United States)

    Sánchez, L; Ruiz, N; Leranoz, S; Viñas, M; Puig, M

    1997-09-01

    Three different porins from Serratia marcescens were described. They were named Omp1, Omp2 and Omp3 and their molecular weights were 42, 40 and 39 kDa respectively. Omp2 and Omp3 showed osmoregulation and thermoregulation in a similar way to OmpC and OmpF of Escherichia coli. Permeability coefficients of the outer membrane of this species were calculated following the Zimmermann and Rosselet method. P values were similar to those obtained in Escherichia coli, which suggests that the chromosomal beta-lactamase would play a major role in the resistance of Serratia marcescens to beta-lactam antibiotics. Both MIC values and permeabilities were modified by salycilates and acetylsalycilate. Synergism between the outer membrane and the beta-lactamase was also evaluated. When bacteria grew in the presence of a beta-lactam in the medium, the beta-lactamase accounted for most of the resistance.

  9. Prevalent serogroups and antibiotic sensitivity of Neisseria gonorrhoeae

    Directory of Open Access Journals (Sweden)

    Aggarwal S

    1992-01-01

    Full Text Available One hundred and thirty two cases clinically labeled as acute gonorrhoea were investigated for gonococcal etiology. Smears were positive in 110 (83.3% cases and among these N. gonorrhoeae could be identified in 102 (77.3% cases by culture method. Strains were examined for serogrouping by monoclonal GC test which utilizes the principle of co-agglutination and detects the antigens of outer membrane protein. 96(94.1% strains belonged to serogroup W II/III, showing it to be the major serogroup circulating in the community. The strains were tested for sensitivity against 7 antibiotics. The largest proportion (30.4% of strains were resistant to penicillin (MIC>O. 125 IU/ml. Resistance to cotrimoxazole, erythromycin, cephalaxin and tetracycline was noted as 18.6, 17.6, 7.8 and 5.8 percent respectively. Strains showing resistance concurrently to two or more drugs were observed. All restrains were sensitive to gentamicin and norfloxacin. None of the strains was penicillinase producer.

  10. Isolation and antibiotic sensitivity of Aeromonas from children with diarrhea

    Directory of Open Access Journals (Sweden)

    Meiyanti Meiyanti

    2016-02-01

    Full Text Available Aeromonas species are gram-negative, motile, facultative anaerobic, rod shaped, oxidase positive bacteria of the recently assigned family Aeromonadaceae. The significance of Aeromonas species as causative agent of human diarrhoea has recently been established. The aim of the present study was to investigate the distribution, and antibiotic sensitivity of Aeromonas in nonhospitalized children with diarrhea.One hundred and seventeen rectal swabs from children with diarhhea were cultured for isolation of Aeromonas organisms as the etiological agents. In addition to Aeromonas, other enteric pathogens were also isolated. Overall, the isolates of enteric pathogens amounted to 36.8%, consisting of Salmonella, Shigella, Aeromonas, and Vibrio. Aeromonas was only found in 5.1% of cultures, with a ratio of A. caviae and A. hydrophila of 2:1, while Salmonella made up the majority of causative organisms with an isolation frequency of 18.8%, followed by Shigella with 11.1%. In this study no isolates of Vibrio cholerae O1 were found as etiological agents of diarrhea; however, V. cholerae non-O1 and V. parahaemolyticus were found in small numbers (<1%. All isolates of Aeromonas were resistant to ampicillin and tetracycline, but sensitive to ciprofloxacin and ceftriaxone, as were the other enteric pathogens. Although the frequency of isolation of these enteric pathogens was higher than for Vibrio spp., their role in infective diarrhea was less clearcut in comparison with Salmonella and Shigella.

  11. Antibiotics

    Science.gov (United States)

    Antibiotics are powerful medicines that fight bacterial infections. Used properly, antibiotics can save lives. They either kill bacteria or ... natural defenses can usually take it from there. Antibiotics do not fight infections caused by viruses, such ...

  12. Subclinical mastitis in sheep: Causes and their sensitivity to antibiotics

    Directory of Open Access Journals (Sweden)

    Vakanjac Slobodanka

    2010-01-01

    Full Text Available The California mastitis test (CMT was used to examine the milk of 6609 sheep, actually, from 13218 mammary complexes. A total of 986 milk samples were found to contain an increased number of somatic cells, and causes of mastitis were isolated from 910 (92.3% of these samples. The most frequently isolated microorganisms were: E. coli isolated from 189 (20.76% samples, Micrococcus sp from 186 (20.43% samples, Bacillus sp. from 177 (19.45%, Staphylococcus aureus from 172 (18.9% samples, and Proteus sp. from 121 (13.29% samples of sheep milk. Coagulase-negative staphylococci (CNS were isolated in a much smaller number, from 25 (2.74% samples, Streptococcus sp. was isolated from 19 (2.08% samples, Pseudomonas sp. from 14 (1.53% samples, haemolytic E. coli was isolated from only 6 (0.65% samples, and Streptococcus agalactiae from only one sample. Among the 25 isolates of coagulase-negative staphylococci, 16 (64% isolates were identified as Staphylococcus chromogenes, and 9 (36% isolates as Staphylococcus simulans. The sensitivity of the isolated causes of mastitis to antibiotics was examined using the disc diffusion method. .

  13. Single daily dosing of antibiotics: importance of in vitro killing rate, serum half-life, and protein binding.

    Science.gov (United States)

    Potel, G; Chau, N P; Pangon, B; Fantin, B; Vallois, J M; Faurisson, F; Carbon, C

    1991-10-01

    The relative importance of pharmacokinetic and pharmacodynamic parameters for the feasibility of a single daily dose (SDD) of antibiotics remains to be established. Therefore, we studied the relationship between in vitro bacteriological parameters (MIC, MBC, and killing rate [KR], defined as the reduction in the inoculum within 3 h), pharmacokinetic parameters (t1/2 and protein binding [PB], and in vivo antibacterial effect of a single antibiotic dose in an experimental rabbit model of Escherichia coli endocarditis. Nine antibiotics were investigated: two aminoglycosides, two quinolones, and five beta-lactams. For each drug, the minimal effective dose (MED) (in milligrams per kilogram) was defined as the lowest dose able to achieve a significant difference (P less than 0.05) of CFU in the vegetations in comparison with controls 24 h after a single intravenous injection. Aminoglycosides and quinolones had the lowest MEDs, followed by beta-lactams. Univariate regression analysis showed that KR was the major determinant of MED. A stepwise regression analysis showed that t1/2 significantly improved the predictive value of KR, while PB, MIC, and MBC did not. The final equation was MED = 1,586-238 KR-297 t1/2 (r = 0.90, P = 0.01). We concluded that the pharmacodynamic parameters (especially the high KR) of aminoglycosides and quinolones explained their low MEDs and might allow SDD. In contrast, the low KR of beta-lactams emphasized the critical importance of a long t1/2, as for ceftriaxone, allowing the use of this beta-lactam alone in SDD.

  14. MRSA Incidence and Antibiotic Trends in Urban Hand Infections: A 10-Year Longitudinal Study.

    Science.gov (United States)

    Kistler, Justin M; Thoder, Joseph J; Ilyas, Asif M

    2018-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is the most reported pathogen in hand infections at urban medical centers throughout the country. Antibiotic sensitivity trends are not well known. The purposes of this study were to examine and determine the drug resistance trends for MRSA infections of the hand and to provide recommendations for empiric antibiotic treatment based on sensitivity profiles. A 10-year longitudinal, retrospective chart review was performed on all culture-positive hand infections encountered at a single urban medical center from 2005 to 2014. The proportions of all organisms were calculated for each year and collectively. MRSA infections were additionally subanalyzed for antibiotic sensitivity. A total of 815 culture-positive hand infections were identified. Overall, MRSA grew on culture in 46% of cases. A trend toward decreasing annual MRSA incidence was noted over the 10-year study period. There was a steady increase in polymicrobial infections during the same time. Resistance to clindamycin increased steadily during the 10-year study, starting at 4% in 2008 but growing to 31% by 2014. Similarly, levofloxacin resistance consistently increased throughout the study, reaching its peak at 56% in 2014. The annual incidence of MRSA in hand infections has declined overall but remains the most common pathogen. There has been an alternative increase in the number of polymicrobial infections. MRSA resistance to clindamycin and levofloxacin consistently increased during the study period. Empiric antibiotic therapy for hand infections should not only avoid penicillin and other beta-lactams but should also consider avoiding clindamycin and levofloxacin for empiric treatment.

  15. Expression, purification, crystallization, and preliminary X-ray crystallographic analysis of OXA-17, an extended-spectrum {beta}-lactamase conferring severe antibiotic resistance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. H., E-mail: msgjhlee@mju.ac.kr; Sohn, S. G., E-mail: sgsohn@mju.ac.kr; Jung, H. I., E-mail: jhinumber1@hanmail.net; An, Y. J., E-mail: anyj0120@hanmail.net; Lee, S. H., E-mail: sangheelee@mju.ac.kr [Myongji University, Drug Resistance Proteomics Laboratory, Department of Biological Sciences (Korea, Republic of)

    2013-07-15

    OXA-17, an extended-spectrum {beta}-lactamase (ESBL) conferring severe antibiotic resistance, hydrolytically inactivates {beta}-lactam antibiotics, inducing a lack of eradication of pathogenic bacteria by oxyimino {beta}-lactams and not helping hospital infection control. Thus, the enzyme is a potential target for developing antimicrobial agents against pathogens producing ESBLs. OXA-17 was purified and crystallized at 298 K. X-ray diffraction data from OXA-17 crystal have been collected to 1.85 A resolution using synchrotron radiation. The crystal of OXA-17 belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 48.37, b = 101.12, and c = 126.07 A. Analysis of the packing density shows that the asymmetric unit probably contains two molecules with a solvent content of 54.6%.

  16. Locally prepared antibiotic sensitivity discs: a substitute for imported ...

    African Journals Online (AJOL)

    Zones of inhibition were compared with those obtained from commercial antibiotic discs. Results obtained showed that discs prepared locally from antibiotic tablets, performed comparably with commercially obtained discs. There was no significant statistical difference between the two tested discs. We therefore recommend ...

  17. Effect of antibiotic therapy on the sensitivity of indium-111-labeled leukocyte scans

    International Nuclear Information System (INIS)

    Datz, F.L.; Thorne, D.A.

    1986-01-01

    Although 111 In-labeled leukocytes have been shown to be a useful technique for detecting infection, it has been postulated that antibiotic therapy may reduce the sensitivity of the leukocyte scan. Many patients with suspected bacterial infections are placed on antibiotics before a definite site of infection has been identified. Three hundred twelve leukocyte scans on 271 patients were retrospectively reviewed and classified as positive or negative, and as to whether or not they were being treated with antibiotics at the time the leukocyte scan was performed. The overall sensitivity, considering all 312 studies, was 90%. One hundred sixty-nine patient studies were on patients receiving antibiotics; 143 studies were on patients not on antibiotics. The sensitivity of the leukocyte scan was 88.7% in patients on antibiotic therapy; it was 92.1% in those who were not receiving antibiotics. The differences in sensitivity between the two groups were not significantly different (p less than 0.05). We conclude that antibiotic therapy does not affect the sensitivity of the 111 In-labeled leukocyte scan

  18. Antibiotic Sensitivity in Pseudomonas aeruginosa of Diabetic Patient’s Foot Ulcer

    OpenAIRE

    Pratiwi Apridamayanti; Khairunnisa Azani Meilinasary; Rafika Sari

    2016-01-01

    Diabetes Mellitus (DM) patients are at risk to have the diabetic ulcer. The main reason for DM’s patient with ulcer complication to be treated and healed in hospital is bacterial infection. One of many bacteria that infects diabetic ulcer is Pseudomonas aeruginosa. This conditian can be treated by antibiotic. The using antibiotic is often inaccurate causing the microbe resistance. To choose the right antibiotic, it needs to test the antibiotic’s sensitivity towards Pseudomonas aeruginosa. The...

  19. Molecular Level Investigation of Staphylococci’s Resistance Mechanisms to Antibiotics

    Directory of Open Access Journals (Sweden)

    Lavinia Lorena PRUTEANU

    2017-09-01

    Full Text Available Polymerase chain reaction (PCR techniques development allows elaboration of many assays for identification of bacteria’s resistance mechanisms to antibiotics. Following this idea, the results of molecular level investigation of bacteria’s resistance mechanisms to antibiotics may give many opportunities to find more rapid methods for identifying the genes which are responsible for antibiotic resistance induction. The aim of this study was to investigate antibiotic resistance genes in Staphylococcus bacteria on molecular level. As classes of antibiotics it was used macrolides-lincosamides-streptogramin B (MLSB and beta-lactams. In the proposed study the bacterial strains are represented by 50 isolates of Staphylococcus. The bacterial strains were analyzed using polymerase chain reaction to identify the nuc, tuf, tst, sea, pathogenic activity genes. After this, the bacteria were tested for ermA, ermB, ermC genes and for mecA, femA which are involved in resistance to macrolides, lincosamides, streptogramin B and to beta-lactams, respectively. The presence or the absence of these genes confirms that tested strains are resistant to specific antibiotic or not. Bacteria pathogenic activity was emphasized by genes as follows: sea (enterotoxin which was found at all isolates, tst (toxic shock toxin gene was not detected in any of isolates and tuf gene (elongation factor was obtained with one pair of primers. Resistance to beta-lactams was evidenced by the presence of mecA in all isolates and femA in some strains. Each of ermC, ermA and ermB, macrolides-lincosamides-streptogramin B resistance genes, were detected.

  20. Characterization of 3 Strains of Yersinia Pestis

    National Research Council Canada - National Science Library

    Kournikakis, B

    2000-01-01

    .... Antibiotic sensitivities showed that the 3 strains were sensitive to aminoglycosides, the cephalosporins/ cephams, most of the beta lactams/penicillins (e.g. ampicillin) and quinolones (e.g. ciprofloxacin...

  1. The Effect of Gamma Irradiation on Salmonella Chester and Its Sensitivity to Antibiotics

    International Nuclear Information System (INIS)

    Basry, T. Hasan

    2000-01-01

    The sensitivity changes of Salmonella chester (S. chester) to antibiotics as the results of gamma irradiation has not much been studied. To understand the sensitivity changes of S. chester to several antibiotics as the results of gamma irradiation with the doses of 1.0; 2.5; and 5.0 kGy, an investigation was carried out using re subculture method. The irradiation effects was evaluated by using Complete. Randomized Design with factorial pattern and the data processing by Analyses of Variance and Duincan test. It revealed that after irradiation with doses of 1.0; and 2.5 kGy, S. chester more sensitive to antibiotics Amphycillin, Tetracyclin and Chloramphenicol. It was also found that using different media culture during irradiation, the sensitivity of S. chester to antibiotics was also different

  2. Radioactivity measurements for determining bacterial increase and sensitivity to antibiotics. [/sup 14/C tracer

    Energy Technology Data Exchange (ETDEWEB)

    Jaszsagi-Nagy, E [Magyar Tudomanyos Akademia, Budapest; Lendvay, J [Orszagos Frederic Joliot-Curie Sugarbiologiai es Sugaregeszsegugyi Kutato Intezet, Budapest (Hungary)

    1976-01-01

    The authors elaborated a sensitive and objective measuring method for determining the bacteria increase in biological material and the sensitivity to antibiotics. When /sup 14/C glucose is added to the medium as the single source of sugar, the respiratory carbon dioxide formed by the bacteria reflects the rate of increase. The released /sup 14/C dioxide can be measured continuously without loss to the environment and the degree of bacterial infection and the antibiotic activity, respectively, can be determined.

  3. Bacteriological profile and antibiotic sensitivity pattern in patients with Urinary tract infection

    OpenAIRE

    N Subedi; S Pudasaini

    2017-01-01

    Background: Urinary tract infection is one of the common bacterial infections seeking treatment in clinical practice. A variety of organisms are associated with UTI and the most common organisms are Escherichia coli and other coliforms. Bacteriological investigations of UTI are not complete without antibiotic sensitivity test of the isolate. The aim of this study is to determine the bacteriological profile and antibiotic sensitivity patterns and their disease association.Materials and methods...

  4. Profile of antibiotic consumption, sensitivity and resistance in an urban area of Andhra Pradesh, India.

    Science.gov (United States)

    Peripi, Sunita Bhargavi; Thadepalli, Venu Gopala Rao; Khagga, Mukkanti; Tripuraribhatla, Prasanna Krishna; Bharadwaj, Dinesh Kumar

    2012-04-01

    Antibiotics are an important category of drugs in which indiscriminate use can affect the susceptibility patterns among infectious organisms, resulting in antibiotic resistance. Data on antibiotic usage and susceptibility patterns were collected from public and private health centres in Vijayawada, Andhra Pradesh, India, through the use of questionnaires. The data collected were then coded, tabulated, computed and evaluated using statistical analysis. The consumption profile of the different categories of drugs used in public and private hospitals was as follows: nutrition and metabolism products 19.0%; gastrointestinal disorder-related drugs 18.5%; antibiotics 16.8%; anti-pyretics and anti-analgesics 20.6%. These drugs were found to be in high demand. Among the antibiotics, aminoglycosides (amikacin), quinolones (ofloxacin, ciprofloxacin), tetracyclines (doxycycline), penicillin (ampicillin) and sulphonamides (co-trimoxazole) were the most commonly prescribed drugs for antibiotic therapy. 46% of the culture laboratory reports were positive with the following organism profile: Escherichia coli (36%), Klebsiella pneumoniae (16%), Staphylococcus aureus (29%), Enterococcus faecalis (9%) and Pseudomonas aeruginosa (10%). In terms of the sensitivity profile of antibacterials, amikacin (66.9%) was the only antibiotic showing sensitivity patterns, while the majority of antibiotics, such as cotrimoxazole, nalidixic acid, amoxicillin, gentamycin and norfloxacin, had acquired a resistance rate of 55.1%-80.6%. The results of this study suggest that indiscriminate prescription and consumption of new broad-spectrum antibiotics against sensitive organisms results in the development of antimicrobial resistance. Therefore, there is an urgent need to curb the excessive use of antibiotics in local hospitals in order to control the trend of increasing antimicrobial resistance to antibiotics.

  5. Profile of sensitivity and resistance to antibiotics of Staphylococcus ...

    African Journals Online (AJOL)

    Staphylococcus aureus is a bacterial specie that opposed more resistance again many antibiotics. This study aimed to determine the resistance profile of Staphylococcus aureus isolated from biological patient's liquids. A total of 303 samples including urine and vaginal pus samples from human were collected.

  6. Microbial profile, antibiotic sensitivity and heat resistance of bacterial ...

    African Journals Online (AJOL)

    Aim: This study was aimed at determining the prevalence, antibiotic resistance and heat resistance profile of bacterial isolates obtained from ready to eat roasted beef (suya) sold in Abuja, Nigeria. Methods and Results: Fifty samples of suya were purchased from different vendors within the Federal Capital Territory and ...

  7. Methicillin resistant S. aureus (MRSA) and their antibiotic sensitivity ...

    African Journals Online (AJOL)

    Method: One hundred and eighty five (185) S. aureus isolates from various clinical specimens obtained over a 12-month period in the Microbiology Department of Aminu Kano Teaching Hospital (AKTH) were subjected to methicillin susceptibility testing, while including susceptibility testing to other antibiotics by the disc ...

  8. Killing curve activity of ciprofloxacin is comparable to synergistic effect of beta-lactam-tobramycin combinations against Haemophilus species endocarditis strains

    DEFF Research Database (Denmark)

    Westh, H; Frimodt-Møller, N; Gutschik, E

    1992-01-01

    Nine Haemophilus species strains, all beta-lactamase negative, isolated from patients with endocarditis were tested in killing curve experiments. Antibiotics used were penicillin, amoxicillin, aztreonam alone and in combination with tobramycin, as well as ciprofloxacin alone. Synergism between beta...

  9. Evaluation of multiplex polymerase chain reaction as an alternative to conventional antibiotic sensitivity test

    Directory of Open Access Journals (Sweden)

    K. Rathore

    2018-04-01

    Full Text Available Aim: This study was designed to evaluate the potential of the use of multiplex polymerase chain reaction (PCR as an alternative to conventional antibiotic sensitivity test. Materials and Methods: Isolates of Staphylococcus aureus (total = 36 from clinical cases presented to Teaching Veterinary Clinical Complex of College of Veterinary and Animal Sciences (CVAS, Navania, Udaipur, were characterized by morphological, cultural, and biochemical methods. Then, the isolates were further subjected to molecular characterization by PCR targeting S. aureus-specific sequence (107 bp. Phenotypic antibiotic sensitivity pattern was analyzed by Kirby Bauer disc diffusion method against 11 commonly used antibiotics in veterinary medicine in and around Udaipur region. The genotypic antibiotic sensitivity pattern was studied against methicillin, aminoglycosides, and tetracycline targeting the gene mecA, aacA-aphD, and tetK by multiplex PCR. Results: There was 100% correlation between the phenotype and genotype of aminoglycoside resistance, more than 90% correlation for methicillin resistance, and 58.3% in the case tetracycline resistance. Conclusion: As there is a good correlation between phenotype and genotype of antibiotic resistance, multiplex PCR can be used as an alternative to the conventional antibiotic susceptibility testing, as it can give a rapid and true prediction of antibiotic sensitivity pattern.

  10. A New Twist to the Kirby-Bauer Antibiotic Susceptibility Test Activity?Increasing Antibiotic Sensitivity of Pseudomonas fluorescens through Thermal Stress

    OpenAIRE

    Gerbig, Donald G.; Engohang-Ndong, Jean; Aubihl, Heather

    2013-01-01

    Antibiotic sensitivity and the effect of temperature on microbial growth are two standard laboratory activities found in most microbial laboratory manuals. We have found a novel way to combine the two activities to demonstrate how temperature can influence antibiotic sensitivity using a standard incubator in instructional laboratory settings. This activity reinforces the important concepts of microbial growth and temperature along with Kirby-Bauer antibiotic susceptibility testing. We found t...

  11. Selenium-mediated protection in reversing the sensitivity of bacterium to the bactericidal antibiotics.

    Science.gov (United States)

    Li, Zhonglei; Tan, Jun; Shao, Lei; Dong, Xiaojing; Ye, Richard D; Chen, Daijie

    2017-05-01

    Inducing production of damaging reactive oxygen species (ROS) is an important criterion to distinguish the bactericidal antibiotics from bacteriostatic antibiotics. Selenoenzymes were generally recognized to be a powerful antioxidant capable of scavenging free radicals, protecting the cells from the harmful effects of ROS. Therefore, the present study was carried out to investigate the selenium (Se)-mediated protection in reversing antibiotic sensitivity and the role of selenoenzymes in alleviating the negative effects of oxidative stress. The cellular antioxidant activity of Se-enriched bacteria was analyzed, as well as intracellular ROS production and elimination when Se-enriched bacteria in the presence of various antibiotics. Compared to complete inhibition of the parental strain by bactericidal antibiotics, it only exhibited slight and reversible inhibition of Se-enriched Escherichia coli ATCC25922 and Staphylococcus aureus ATCC25923 at the same conditions, which indicated that intracellular selenium provided substantial protection against antibiotics. ROS generation caused by bactericidal antibiotics was confirmed by fluorescence spectrophotometry using 2', 7'-dichloro- uorescein diacetate (DCFH-DA) as substrate. The time course experiments of pretreatment with selenium showed significant decrease of ROS level at 2h. In summary, the present study provides experimental evidence supporting selenoenzymes has good scavenging effect to ROS and can protect bacteria from oxidative stress injury induced by bactericidal antibiotics. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Redeploying β-Lactam Antibiotics as a Novel Antivirulence Strategy for the Treatment of Methicillin-Resistant Staphylococcus aureus Infections

    Energy Technology Data Exchange (ETDEWEB)

    Waters, Elaine M.; Rudkin, Justine K.; Coughlan, Simone; Clair, Geremy C.; Adkins, Joshua N.; Gore, Suzanna; Xia, Guoqing; Black, Nikki S.; Downing, Tim; O' Neill, Eoghan; Kadioglu, Aras; O' Gara, James P.

    2016-11-14

    Innovative approaches to the use of existing antibiotics is an important strategy in efforts to address the escalating antimicrobial resistance crisis. Here, the beta-lactam antibiotic oxacillin was shown to significantly attenuate the virulence of MRSA despite the pathogen being resistant to this drug. Oxacillin-mediated repression of the Agr quorum-sensing system and altered cell wall architecture, was associated with reduced cytolytic activity and increased susceptibility to host killing. These findings support the inclusion of -lactam antibiotics as an adjunctive anti-virulence therapy in the treatment of MRSA infections, with the potential to significantly improve patient outcomes in a safe, cost effective manner.

  13. Analytical strategy for the detection of antibiotic residues in sheep and goat’s milk

    Energy Technology Data Exchange (ETDEWEB)

    Beltrán, M.C.; Althaus, R.L.; Molina, A.; Berruga, M.I.; Molina, M.P.

    2015-07-01

    The use of antibiotics to treat mastitis and other infectious diseases in dairy sheep and goats is a widespread practice nowadays that can, when not properly applied, result in the contamination of the milk supply. Spanish legislation establishes the control of the presence of antibiotic residues in sheep and goat’s milk using screening methods that detect, at least, beta-lactam drugs. Microbial inhibitor tests using Geobacillus stearothermophilus var. calidolactis and specific receptor-binding assays are most widely employed for this purpose. The detection rates of screening tests routinely used in Spain have been calculated considering the frequency of use of veterinary drugs commonly applied in ovine and caprine livestock to treat and prevent mastitis as well as the test sensitivity toward these substances at safety levels. In general, the use of a single test allows detecting 62.8-82.4% of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of methods were found when goat's milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly, reaching values ≥ 90% in some cases (81.5-90.1% for sheep and 84.7-92.6% for goats). However, the periodical use of screening tests able to detect quinolones, macrolides or aminoglycosides would be recommended to carry out more efficient screening and ensure the safety of milk and dairy products from sheep and goats. (Author)

  14. Analytical strategy for the detection of antibiotic residues in sheep and goat’s milk

    Directory of Open Access Journals (Sweden)

    M. Carmen Beltrán

    2015-03-01

    Full Text Available The use of antibiotics to treat mastitis and other infectious diseases in dairy sheep and goats is a widespread practice nowadays that can, when not properly applied, result in the contamination of the milk supply. Spanish legislation establishes the control of the presence of antibiotic residues in sheep and goat’s milk using screening methods that detect, at least, beta-lactam drugs. Microbial inhibitor tests using Geobacillus stearothermophilus var. calidolactis and specific receptor-binding assays are most widely employed for this purpose. The detection rates of screening tests routinely used in Spain have been calculated considering the frequency of use of veterinary drugs commonly applied in ovine and caprine livestock to treat and prevent mastitis as well as the test sensitivity toward these substances at safety levels. In general, the use of a single test allows detecting 62.8-82.4% of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of methods were found when goat’s milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly, reaching values ≥ 90% in some cases (81.5-90.1% for sheep and 84.7-92.6% for goats. However, the periodical use of screening tests able to detect quinolones, macrolides or aminoglycosides would be recommended to carry out more efficient screening and ensure the safety of milk and dairy products from sheep and goats.

  15. Analytical strategy for the detection of antibiotic residues in sheep and goat’s milk

    International Nuclear Information System (INIS)

    Beltrán, M.C.; Althaus, R.L.; Molina, A.; Berruga, M.I.; Molina, M.P.

    2015-01-01

    The use of antibiotics to treat mastitis and other infectious diseases in dairy sheep and goats is a widespread practice nowadays that can, when not properly applied, result in the contamination of the milk supply. Spanish legislation establishes the control of the presence of antibiotic residues in sheep and goat’s milk using screening methods that detect, at least, beta-lactam drugs. Microbial inhibitor tests using Geobacillus stearothermophilus var. calidolactis and specific receptor-binding assays are most widely employed for this purpose. The detection rates of screening tests routinely used in Spain have been calculated considering the frequency of use of veterinary drugs commonly applied in ovine and caprine livestock to treat and prevent mastitis as well as the test sensitivity toward these substances at safety levels. In general, the use of a single test allows detecting 62.8-82.4% of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of methods were found when goat's milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly, reaching values ≥ 90% in some cases (81.5-90.1% for sheep and 84.7-92.6% for goats). However, the periodical use of screening tests able to detect quinolones, macrolides or aminoglycosides would be recommended to carry out more efficient screening and ensure the safety of milk and dairy products from sheep and goats. (Author)

  16. The occurrence of antibiotics in an urban watershed: from wastewater to drinking water.

    Science.gov (United States)

    Watkinson, A J; Murby, E J; Kolpin, D W; Costanzo, S D

    2009-04-01

    The presence of 28 antibiotics in three hospital effluents, five wastewater treatment plants (WWTPs), six rivers and a drinking water storage catchment were investigated within watersheds of South-East Queensland, Australia. All antibiotics were detected at least once, with the exception of the polypeptide bacitracin which was not detected at all. Antibiotics were found in hospital effluent ranging from 0.01-14.5 microg L(-1), dominated by the beta-lactam, quinolone and sulphonamide groups. Antibiotics were found in WWTP influent up to 64 microg L(-1), dominated by the beta-lactam, quinolone and sulphonamide groups. Investigated WWTPs were highly effective in removing antibiotics from the water phase, with an average removal rate of greater than 80% for all targeted antibiotics. However, antibiotics were still detected in WWTP effluents in the low ng L(-1) range up to a maximum of 3.4 microg L(-1), with the macrolide, quinolone and sulphonamide antibiotics most prevalent. Similarly, antibiotics were detected quite frequently in the low ng L(-1) range, up to 2 microg L(-1) in the surface waters of six investigated rivers including freshwater, estuarine and marine samples. The total investigated antibiotic concentration (TIAC) within the Nerang River was significantly lower (pWWTP discharge to this river is a likely explanation for the significantly lower TIAC and suggests that WWTP discharges are a dominant source of antibiotics to investigated surface waters. A significant difference (pWWTP discharge compared to sites with no WWTP discharge, providing further evidence that WWTPs are an important source of antibiotics to streams. Despite the presence of antibiotics in surface waters used for drinking water extraction, no targeted antibiotics were detected in any drinking water samples.

  17. Sensitivity of certain bacteria to antibiotics and irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Harsojo,; Andini, L S; Siagian, E G; Lina, M R; Zuleiha, S [National Atomic Energy Agency, Jakarta (Indonesia). Pasar Djumat Research Centre

    1981-07-01

    An experiment has been conducted to find vegetative forms of certain bacteria in Indonesia which are resistant to irradiation, the resistance of which will be compared to that of known radioresistant bacteria micrococcus radiodurans. To inactivate the vegetative forms of resistant bacteria to irradiation high doses are needed, while for storage purposes lower doses change the physical and chemical properties of the stored commodity are preferred. For this purpose the bacteria were irradiated in aerobic condition with gamma radiation doses of 0.1, 0.2 and 0.3 kGy, or treated with antibiotics e.g. tetracycline HCl or chloramphenicol with concentrations of 0.1, 0.2 and 0.3 ..mu..g/ml respectively. The results indicated that doses of 0.2 kGy and 0.1 ..mu..g/ml reduced the ability of the bacteria for multiplication.

  18. Multifaceted antibiotic treatment analysis of methicillin-sensitive Staphylococcus aureus bloodstream infections.

    Science.gov (United States)

    Weber, Zhanni; Ariano, Robert; Lagacé-Wiens, Philippe; Zelenitsky, Sheryl

    2016-12-01

    Given the overall prevalence and poor prognosis of Staphylococcus aureus bloodstream infections (BSIs), the study of treatment strategies to improve patient outcomes is important. The aim of this study was to conduct a multifaceted antibiotic treatment analysis of methicillin-sensitive S. aureus (MSSA) BSI and to characterise optimal early antibiotic therapy (within the first 7 days of drawing the index blood culture) for this serious infection. Antibiotic selection was categorised as optimal targeted (intravenous cloxacillin or cefazolin), optimal broad (piperacillin/tazobactam or meropenem), adequate (vancomycin) or inadequate (other antibiotics or oral therapy). A TSE (timing, selection, exposure) score was developed to comprehensively characterise early antibiotic therapy, where higher points corresponded to prompt initiation, optimal antibiotic selection and longer exposure (duration). Amongst 71 cases of complicated MSSA-BSI, end-of-treatment (EOT) response (i.e. clinical cure) was improved when at least adequate antibiotic therapy was initiated within 24 h [71.7% (33/46) vs. 48.0% (12/25); P = 0.047]. Clinical cure was also more likely when therapy included ≥4 days of optimal targeted antibiotics within the first 7 days [74.4% (29/39) vs. 50.0% (16/32); P = 0.03]. The TSE score was an informative index of early antibiotic therapy, with EOT cure documented in 72.0% (36/50) compared with 42.9% (9/21) of cases with scores above and below 15.2, respectively (P = 0.02). In multivariable analysis, lower Charlson comorbidity index, presence of BSI on admission, and optimising early antibiotic therapy, as described above, were associated with clinical cure in patients with MSSA-BSI. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  19. Endophthalmitis caused by Pantoea agglomerans: clinical features, antibiotic sensitivities, and outcomes

    Directory of Open Access Journals (Sweden)

    Venincasa VD

    2015-07-01

    Full Text Available Vincent D Venincasa, Ajay E Kuriyan, Harry W Flynn Jr, Jayanth Sridhar, Darlene Miller Department of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USA Purpose: To report the clinical findings, antibiotic sensitivities, and visual outcomes associated with endophthalmitis caused by Pantoea agglomerans.Methods: A consecutive case series of patients with vitreous culture-positive endophthalmitis caused by P. agglomerans from January 1, 1990 to December 31, 2012 at a large university referral center. Findings from the current study were compared to prior published studies.Results: Of the three study patients that were identified, clinical settings included trauma (n=2 and post-cataract surgery (n=1. Presenting visual acuity was hand motion or worse in all three cases. All isolates were sensitive to ceftazidime, gentamicin, imipenem, and fluoroquinolones. All isolates were resistant to ampicillin. Initial treatment strategies were vitreous tap and intravitreal antibiotic injection (n=1 and pars plana vitrectomy with intravitreal antibiotic injection (n=2. At last follow-up, one patient had no light perception vision, while the other two had best-corrected visual acuity of 20/200 and 20/400.Conclusion: All Pantoea isolates were sensitive to ceftazidime, gentamicin, imipenem, and fluoroquinolones. All patients in the current study received at least one intravitreal antibiotic to which P. agglomerans was shown to be sensitive in vitro. In spite of this, the visual outcomes were generally poor.Keywords: ocular infection, trauma, antibiotic resistance

  20. A Survey on Antimicrobial Sensitivity Pattern of Different Antibiotics ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: A study of antimicrobial sensitivity of Escherichia coli isolated from clinical sources of Medinova ... It also causes urinary tract infection and other .... Ceftriaxone- resistant Salmonella infection acquired by a child from cattle. N. Engl.

  1. Changes in antibiotic sensitivity and cell surface hydrophobicity in Escherichia coli injured by heating, freezing, drying or gamma radiation

    International Nuclear Information System (INIS)

    Mackey, B.M.

    1983-01-01

    Escherichia coli cells exposed to mild heating, freezing and thawing, drying or γ-radiation were sensitised to hydrophobic antibiotics and sodium deoxycholate but not to small hydrophilic antibiotics. These stress treatments also caused increases in cell surface hydrophobicity broadly reflecting the degree of sensitivity to hydrophobic antibiotics. (Auth.)

  2. The Adoption of a Standardized Antibiotic Sensitivity Test in the Philippines

    Directory of Open Access Journals (Sweden)

    Thelma Tupasi-Ramos

    1980-01-01

    Full Text Available With the development and the introduction of a great variety of antibiotic and chemotherapeutic agents, the outlook in the treatment of infections has improved significantly. Unfortunately, however, these agents are not necessarily innocuous to human tissues, so that their use in some instances is associated with some potential hazards including tissue toxicity, hypersensitivity reaction, emergence of bacterial antimicrobial resistance and the development of clinical superinfection. In view of these hazards, therefore, the administration of an antibiotic must be initiated only when there are definite objective evidences of an infection from clinical and laboratory parameters. Furthermore, the choice of antibiotic must be based on objective results of the antibiotic sensitivity test done on the isolated etiologic agent.

  3. Broad spectrum antibiotic enrofloxacin modulates contact sensitivity through gut microbiota in a murine model.

    Science.gov (United States)

    Strzępa, Anna; Majewska-Szczepanik, Monika; Lobo, Francis M; Wen, Li; Szczepanik, Marian

    2017-07-01

    Medical advances in the field of infection therapy have led to an increasing use of antibiotics, which, apart from eliminating pathogens, also partially eliminate naturally existing commensal bacteria. It has become increasingly clear that less exposure to microbiota early in life may contribute to the observed rise in "immune-mediated" diseases, including autoimmunity and allergy. We sought to test whether the change of gut microbiota with the broad spectrum antibiotic enrofloxacin will modulate contact sensitivity (CS) in mice. Natural gut microbiota were modified by oral treatment with enrofloxacin prior to sensitization with trinitrophenyl chloride followed by CS testing. Finally, adoptive cell transfers were performed to characterize the regulatory cells that are induced by microbiota modification. Oral treatment with enrofloxacin suppresses CS and production of anti-trinitrophenyl chloride IgG1 antibodies. Adoptive transfer experiments show that antibiotic administration favors induction of regulatory cells that suppress CS. Flow cytometry and adoptive transfer of purified cells show that antibiotic-induced suppression of CS is mediated by TCR αβ + CD4 + CD25 + FoxP3 + Treg, CD19 + B220 + CD5 + IL-10 + , IL-10 + Tr1, and IL-10 + TCR γδ + cells. Treatment with the antibiotic induces dysbiosis characterized by increased proportion of Clostridium coccoides (cluster XIVa), C coccoides-Eubacterium rectale (cluster XIVab), Bacteroidetes, and Bifidobacterium spp, but decreased segmented filamentous bacteria. Transfer of antibiotic-modified gut microbiota inhibits CS, but this response can be restored through oral transfer of control gut bacteria to antibiotic-treated animals. Oral treatment with a broad spectrum antibiotic modifies gut microbiota composition and promotes anti-inflammatory response, suggesting that manipulation of gut microbiota can be a powerful tool to modulate the course of CS. Copyright © 2017 American Academy of Allergy, Asthma & Immunology

  4. Biochemical characterization of systemic bacteria in bananas, sensitivity to antibiotics and plant phytotoxicity during shoot proliferation

    Directory of Open Access Journals (Sweden)

    Janiffe Peres de Oliveira

    2016-04-01

    Full Text Available The objective of this work was to characterize the biochemically systemic bacterial isolated from banana plants, to evaluate the bacterial sensitivity to antibiotics, and to determine the phytotoxicity of banana shoots during in vitro proliferation. Systemic bacteria belonging to the Klebsiella and Aeromonas genera were isolated from the “Maravilha” (FHIA 01 AAAB, “Preciosa” (PV 4285 AAAB and “Thap Maeo” (AAB varieties and were then characterized. Tests of shoot sensitivity to antibiotics were performed, and the minimum inhibitory concentration (MIC and phytotoxic effects of selected antibiotics to plants were determined. Among the 20 antibiotics evaluated, the strains showed sensitivity to cefaclor, cefalexin, cefalotin, nalidixic acid, chloramphenicol, and vancomycin. However, during MIC determination, the best results were obtained with cefaclor, vancomycin or nalidixic acid alone in concentrations ranging from 512 to 1,024 mg L-1. In culture medium, cefaclor at 1,024 mg L-1 was the only antibiotic to affect the multiplication and the shoot survival in culture.

  5. Antibiotic sensitivity pattern from pregnant women with urinary tract infection in Bangalore, India.

    Science.gov (United States)

    Sibi, G; Kumari, Pinki; Kabungulundabungi, Neema

    2014-09-01

    To determine the antibacterial profile of pregnant women with urinaty tract infections and analyze the antibiotic sensitivity pattern for the effective treatment. A total of 395 urine samples from pregnant women with different gestational age were processed for the isolation of uropathogens and tested against eight groups of antibiotics namely penicillins, cephalosporins, fluoroquinolones, aminoglycosides, macrolides, lincosamides, glycopeptides and sulfonamides. A positive culture percentage of 46.6% was obtained with the highest urinary tract infection in third trimester gestational age. Among the uropathogens isolated, 85.6% were Gram negative and 14.4% were Gram positive with Escherichia coli as the predominant bacteria (43.9%) followed by Klebsiella oxytoca (19.4%) and Klebsiella pneumoniae (13.3%). Antibiotic sensitivity assay revealed that amikacin had the highest overall sensitivity (n=136; 76.7%) and the subsequent highest sensitivity was observed with ciprofloxacin (n=132; 73.3%), clindamycin (n=124; 68.9%), cefotaxime (n=117; 65%) and nalidixic acid (n=115; 63.9%). The findings revealed that uropathogens were more resistant to penicillins, macrolides and glycopeptides which restrict their use in treating urinaty tract infections during pregnancy. In conclusion, common causative bacteria and their antibiotic sensitivity pattern are to be determined along with their safety to mother and fetus for the effective treatment of urinary tract infections during pregnancy. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  6. Comparison of isolates and antibiotic sensitivity pattern in pediatric and adult cancer patients; is it different?

    Science.gov (United States)

    Prabhash, K; Bajpai, J; Gokarn, A; Arora, B; Kurkure, P A; Medhekar, A; Kelkar, R; Biswas, S; Gupta, S; Naronha, V; Shetty, N; Goyel, G; Banavali, S D

    2014-01-01

    Infection is a common cause of mortality and morbidity in cancer patients. Organisms are becoming resistant to antibiotics; age appears to be one of the factors responsible. We analyzed common organisms and their antibiotic sensitivity pattern in the correlation with age. This is a single institutional, retrospective analysis of all culture positive adult and pediatric cancer patients from January 2007 to December 2007. For statistical analysis, Chi-square test for trend was used and P values were obtained. Of 1251 isolates, 262 were from children 12 years of age). Gram-negative organisms were predominant (64.95) while Gram-positive constituted 35.09% of isolates. The most common source in all age groups was peripheral-blood, accounting to 47.8% of all samples. The most common organisms in adults were Pseudomonas aeruginosa (15.3%) while in children it was coagulase negative Staphylococcus aureus (19.8%). Antibiotic sensitivity was different in both groups. In pediatric group higher sensitivity was seen for Cefoparazone-sulbactum, Cefipime, Amikacin, and Tobramycin. No resistance was found for Linezolid. The isolates in both children and adults were predominantly Gram-negative though children had proportionately higher Gram-positive organisms. High-dose cytarabine use, cotrimoxazole prophylaxis, and frequent use of central lines in children especially in hematological malignancies could explain this observation. Children harbor less antibiotic resistance than adults; Uncontrolled, cumulative exposure to antibiotics in our community with increasing age, age-related immune factors and variable bacterial flora in different wards might explain the higher antibiotic resistance in adults. Thus age is an important factor to be considered while deciding empirical antibiotic therapy.

  7. Comparing the sensitivity of chlorophytes, cyanobacteria, and diatoms to major-use antibiotics.

    Science.gov (United States)

    Guo, Jiahua; Selby, Katherine; Boxall, Alistair B A

    2016-10-01

    The occurrence of antibiotic residues in the aquatic environment is an emerging concern. In contrast to daphnia and fish, algae are known to be particularly sensitive to antibiotic exposure. However, to date, a systematic evaluation of the sensitivity of different algal species to antibiotics has not been performed. The aim of the present study was therefore to explore the sensitivity of a battery of algal species toward antibiotic exposures. The present study investigated the growth inhibition effects of 3 major-use antibiotics, tylosin, lincomycin, and trimethoprim, on 7 algal species from the chlorophyte, cyanobacteria, and diatom groups. Based on median effective concentration (EC50) values, cyanobacteria (EC50 = 0.095-0.13 μmol/L) were found to be the most sensitive group to lincomycin followed by chlorophytes (EC50 = 7.36-225.73 μmol/L) and diatoms (EC50 > 225.73 μmol/L). Cyanobacteria were also the most sensitive group to tylosin (EC50 = 0.09-0.092 μmol/L), but, for this compound, diatoms (EC50 = 1.33-5.7 μmol/L) were more sensitive than chlorophytes (EC50 = 4.14-81.2 μmol/L). Diatoms were most sensitive to trimethoprim (EC50 = 7.36-74.61 μmol/L), followed by cyanobacteria (EC50 = 315.78-344.45 μmol/L), and chlorophytes (EC50 > 344.45 μmol/L) for trimethoprim. Although these results partly support the current approach to regulatory environmental risk assessment (whereby cyanobacterial species are recommended for use with antibiotic compounds), they indicate that for some antibiotics this group might not be the most appropriate test organism. It is therefore suggested that environmental risk assessments consider data on 3 algal groups (chlorophytes, cyanobacteria, and diatoms) and use test species from these groups, which are consistently found to be the most sensitive (Pseudokirchneriella subcapitata, Anabaena flos-aquae, and Navicula pelliculosa). Environ Toxicol Chem 2016;35:2587-2596. © 2016 SETAC.

  8. Phenotypic, Genotypic, and Antibiotic Sensitivity Patterns of Strains Isolated from the Cholera Epidemic in Zimbabwe

    NARCIS (Netherlands)

    Islam, Mohammad S.; Mahmud, Zahid H.; Ansaruzzaman, Mohammad; Faruque, Shah M.; Talukder, Kaisar A.; Qadri, Firdausi; Alam, Munirul; Islam, Shafiqul; Bardhan, Pradip K.; Mazumder, Ramendra N.; Khan, Azharul I.; Ahmed, Sirajuddin; Iqbal, Anwarul; Chitsatso, Owen; Mudzori, James; Patel, Sheetal; Midzi, Stanley M.; Charimari, Lincoln; Endtz, Hubert P.; Cravioto, Alejandro

    This paper details the phenotypic, genotypic, and antibiotic sensitivity patterns of 88 Vibrio cholerae strains from Zimbabwe. Of the 88 strains, 83 were classified as "altered El Tor" and 5 as "hybrid El Tor" strains. All of the strains were susceptible to tetracycline, doxycycline, ciprofloxacin,

  9. Differential antibiotic sensitivity determined by the large ribosomal subunit in thermophilic archaea.

    OpenAIRE

    Ruggero, D; Londei, P

    1996-01-01

    Hybrid ribosomes obtained by mixing the ribosomal subunits of the extremely thermophilic archaea Sulfolobus solfataricus and Desulfurococcus mobilis were tested for their sensitivity to selected antibiotics. It is shown that structural differences in the large ribosomal subunits determine qualitatively and quantitatively the patterns of response to alpha-sarcin and paromomycin in these species.

  10. Effects of temperature, genetic variation and species competition on the sensitivity of algae populations to the antibiotic enrofloxacin

    NARCIS (Netherlands)

    Rico, Andreu; Zhao, Wenkai; Gillissen, Frits; Lürling, Miquel; Brink, van den Paul J.

    2018-01-01

    Primary producers are amongst the most sensitive organisms to antibiotic pollution in aquatic ecosystems. To date, there is little information on how different environmental conditions may affect their sensitivity to antibiotics. In this study we assessed how temperature, genetic variation and

  11. Development of SYN-004, an oral beta-lactamase treatment to protect the gut microbiome from antibiotic-mediated damage and prevent Clostridium difficile infection.

    Science.gov (United States)

    Kaleko, Michael; Bristol, J Andrew; Hubert, Steven; Parsley, Todd; Widmer, Giovanni; Tzipori, Saul; Subramanian, Poorani; Hasan, Nur; Koski, Perrti; Kokai-Kun, John; Sliman, Joseph; Jones, Annie; Connelly, Sheila

    2016-10-01

    The gut microbiome, composed of the microflora that inhabit the gastrointestinal tract and their genomes, make up a complex ecosystem that can be disrupted by antibiotic use. The ensuing dysbiosis is conducive to the emergence of opportunistic pathogens such as Clostridium difficile. A novel approach to protect the microbiome from antibiotic-mediated dysbiosis is the use of beta-lactamase enzymes to degrade residual antibiotics in the gastrointestinal tract before the microflora are harmed. Here we present the preclinical development and early clinical studies of the beta-lactamase enzymes, P3A, currently referred to as SYN-004, and its precursor, P1A. Both P1A and SYN-004 were designed as orally-delivered, non-systemically available therapeutics for use with intravenous beta-lactam antibiotics. SYN-004 was engineered from P1A, a beta-lactamase isolated from Bacillus licheniformis, to broaden its antibiotic degradation profile. SYN-004 efficiently hydrolyses penicillins and cephalosporins, the most widely used IV beta-lactam antibiotics. In animal studies, SYN-004 degraded ceftriaxone in the GI tract of dogs and protected the microbiome of pigs from ceftriaxone-induced changes. Phase I clinical studies demonstrated SYN-004 safety and tolerability. Phase 2 studies are in progress to assess the utility of SYN-004 for the prevention of antibiotic-associated diarrhea and Clostridium difficile disease. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Prevalence of quinolone resistance determinant qnrA6 among broad- and extended-spectrum beta-lactam-resistant Proteus mirabilis and Morganella morganii clinical isolates with sul1-type class 1 integron association in a Tunisian Hospital.

    Science.gov (United States)

    Mahrouki, Sihem; Perilli, Mariagrazia; Bourouis, Amel; Chihi, Hela; Ferjani, Mustapha; Ben Moussa, Mohamed; Amicosante, Gianfranco; Belhadj, Omrane

    2013-08-01

    The aim of this study was to investigate the prevalence and the emergence of plasmid-mediated quinolone resistance among broad-spectrum beta-lactam-resistant Proteus mirabilis and Morganella morganii clinical isolates recovered in the Military Hospital in Tunisia. Of 200 strains examined, 50 exhibited resistance to quinolones. Quinolone resistance determinants (qnr and aac(6')-Ib-cr) were characterized by multiplex PCR and sequencing. Chromosomal quinolone resistance mutations in the quinolone resistance-determining region (QRDR) and class 1 integron characterization were analysed by PCR and sequencing. The clonal relationship between the isolates was studied by pulsed-field gel electrophoresis (PFGE). Fourteen isolates harboured qnrA6 and among them 8 (57%) were extended-spectrum beta-lactamase (ESBL) producers, whilst 12 (85%) isolates harboured blaDHA-1. Mutations in the QRDR were detected in gyrA (Ser83Ile, Glu87Lys), gyrB (Ser464Phe), and parC (Ser80Ile). qnrA6 and blaDHA-1 genes were found embedded in complex sul1-type class 1 integrons. A gene cassette carrying aac(6')-Ib-cr was found located in the class 1 integron upstream of the qacEΔ1 gene. According to the PFGE analysis, the isolates were clonally unrelated. This is the first description in North Africa of class 1 integrons carrying blaDHA-1, qnrA6 gene, and aac(6')-Ib-cr determinants in clinical strains of Proteus mirabilis and Morganella morganii.

  13. In Vitro Sensitivity of Bacteria to Various Antibiotics, Obtained from Women Suffering From Cystits

    Directory of Open Access Journals (Sweden)

    Sena Erdogan Aydos

    2006-06-01

    Full Text Available % 25-30 of women between 20-40 ages have urinary tract infection. In our country every year 5 million cases of cystitis occur. Some investigators suggest that empiric treatment for a short duration without doing culture is useful, safe and cost effective by estimating the factors and antibiotic’s sensitivity in the beginning in women whom are diagnosed as acute uncomplicated cystitis. On the other hand, a problem due to treatments of urinary tract infection has begun because of resistance producing from widespread using antibiotics for inappropriate indications. Therefore, in order to define appropriate antibiotics in urinary tract infection periodic surveillance is needed for checking local resistance condition. In this study, we aim to assess a clinical approach for antibiotic selection in empiric treatment of cystitis without doing culture or in beginning of cystitis therapy while waiting for the culture’s results."

  14. Use of a radiorespirometric assay for testing the antibiotic sensitivity of catheter-associated bacteria

    International Nuclear Information System (INIS)

    Ladd, T.I.; Schmiel, D.; Nickel, J.C.; Costerton, J.W.

    1987-01-01

    A 14 C-radiorespirometric assay was used to show the sensitivity of fixed-film (sessile), catheter-associated and free-living (planktonic) cells of Pseudomonas aeruginosa to varying concentrations (100 micrograms/mL to 1000 micrograms/mL) tobramycin sulfate. This strain of P. aeruginosa has an MIC of 0.6 microgram/ml and an MBC of 50 micrograms/mL when tested by conventional methods. When 14 C-glutamic acid was used as a substrate in this radiorespirometric assay, it could be completed in less than one hour and planktonic samples showed a significant reduction in mineralization activity (evolution of 14 CO 2 ) within eight hours of the antibiotic challenge. These changes in respiratory activity appeared to be dose and time dependent. Within 18 hr. at 1000 micrograms/mL, there was no significant residual respiratory activity in planktonic samples. Some residual respiratory activity was detected, however, in samples exposed to 100 micrograms/mL for 36 hours. The mineralization activity of sessile catheter-associated bacteria was unaffected by four hr. and eight hr. exposures to 1000 micrograms/mL of the antibiotic. A significant reduction in respiratory activity was recorded in catheter samples exposed for 18 hr. or more at each concentration examined. Unlike the planktonic samples, however, the antibiotic challenge failed to eradicate the metabolic activity of the attached bacteria. Antibiotic stressed, catheter-associated bacteria transferred to a post-exposure enrichment broth showed a limited ability to re-establish respiratory activity. This apparent recovery was limited to antibiotic exposures less than 24 hr. and was not observed in planktonic samples. The radioisotopic assay is a non-culture method which can be used to assess the antibiotic sensitivity of both planktonic bacteria and in situ biofilm populations

  15. Antibiotic sensitivity pattern of uropathogens from pregnant women with urinary tract infection in Abakaliki, Nigeria

    Directory of Open Access Journals (Sweden)

    Onoh RC

    2013-12-01

    Full Text Available RC Onoh,1 OUJ Umeora,1 VE Egwuatu,2 PO Ezeonu,1 TJP Onoh31Department of Obstetrics and Gynecology, Federal Teaching Hospital Abakaliki, Ebonyi State, Nigeria; 2Department of Obstetrics and Gynecology, Enugu State University Teaching Hospital, Enugu State, Nigeria; 3Department of Pathology, Federal Teaching Hospital Abakaliki, Ebonyi State, NigeriaBackground: Urinary tract infection (UTI is a common bacterial infection during pregnancy and a significant cause of perinatal and maternal morbidity and mortality. The causative bacteria have remained virtually the same although with variations in individual prevalence. There has been an increasing resistance by these bacteria to the commonly available antibiotics.Objectives: To determine the prevalence of UTI, the common causative bacteria, and their antibiotic sensitivity pattern among pregnant women with UTI.Methodology: This is a descriptive study that was carried out at the Obstetrics Department of two tertiary institutions in Abakaliki, Ebonyi State, Nigeria (Federal Medical Center and Ebonyi State University Teaching Hospital over a period of 12 months. Midstream urine specimens from selected pregnant women with clinical features of UTI were collected for microscopy, culture, and sensitivity. The results were analyzed with the 2008 Epi Info™ software.Results: A total of 542 pregnant women presented with symptoms of UTI and were recruited for the study over the study period. Of the 542 pregnant women, 252 (46.5% had significant bacteriuria with positive urine culture and varying antibiotic sensitivity pattern. The prevalence of symptomatic UTI was 3%. Escherichia coli was the most common bacteria isolated with a percentage of 50.8%. Other isolated micro organisms included Stapylococcus aereus (52 cultures, 20.6%, Proteus mirabilis (24 cultures, 9.5%, S. saprophyticus (18 cultures, 7.1%, Streptococcus spp. (14 cultures, 5.6%, Citrobacter spp. (5 cultures, 2.0%, Klebsiella spp. (4 cultures, 1

  16. Factors influencing antibiotic prescribing habits and use of sensitivity testing amongst veterinarians in Europe.

    Science.gov (United States)

    De Briyne, N; Atkinson, J; Pokludová, L; Borriello, S P; Price, S

    2013-11-16

    The Heads of Medicines Agencies and the Federation of Veterinarians of Europe undertook a survey to gain a better insight into the decision-making process of veterinarians in Europe when deciding which antibiotics to prescribe. The survey was completed by 3004 practitioners from 25 European countries. Analysis was to the level of different types of practitioner (food producing (FP) animals, companion animals, equines) and country for Belgium, Czech Republic, France, Germany, Spain, Sweden and the UK. Responses indicate no single information source is universally considered critical, though training, published literature and experience were the most important. Factors recorded which most strongly influenced prescribing behaviour were sensitivity tests, own experience, the risk for antibiotic resistance developing and ease of administration. Most practitioners usually take into account responsible use warnings. Antibiotic sensitivity testing is usually performed where a treatment failure has occurred. Significant differences were observed in the frequency of sensitivity testing at the level of types of practitioners and country. The responses indicate a need to improve sensitivity tests and services, with the availability of rapid and cheaper testing being key factors.

  17. Frequency of common bacteria and their antibiotic sensitivity pattern in diabetics presenting with foot ulcer

    International Nuclear Information System (INIS)

    Rahim, F.; Ishfaq, M.; Rahman, S.U.; Afridi, A.K.

    2016-01-01

    Foot ulcers are one of the most important complications of diabetes mellitus and often lead to lower limb amputation. Diabetic foot ulcers are susceptible to infection. The objective of this study was to determine the frequency of common bacteria infecting these ulcers and their antibiotic sensitivity pattern. Methods: This descriptive cross-sectional study was performed in the Departments of Medicine and Surgery, Khyber Teaching Hospital, Peshawar from April, 2011 to February, 2012. Specimens collected from ulcers of 131 patients were inoculated on Blood Agar and MacConkey Agar, and antibiotic sensitivity was tested using standard disc diffusion method. Results: Out of 131, specimens from 120 patients yielded 176 bacteria. Sixty-six patients had monomicrobial infection while polymicrobial growth was obtained in 54 patients. Overall, Staphylococcus aureus (38.6%) was the most common isolate followed by Pseudomonas aeruginosa (27.3%). Staphylococcus aureus was most often sensitive to Moxifloxacin, Imipenem/Meropenem, Vancomycin and Linezolid while it showed varying sensitivity to Penicillins and Cephalosporins. 47.1% isolates of Staphylococcus aureus were resistant to Methicillin. Most of the gram negative rods were sensitive to Imipenem/Meropenem, Piperacillin-Tazobactam and Ticarcillin-Clavulanate. Majority of gram negative bacteria were found resistant to Cephalosporins and Moxifloxacin except Pseudomonas which showed variable sensitivity to Ceftriaxone, Ceftazidime and Moxifloxacin. Conclusions: Majority of isolates were found resistant to the commonly used antibiotics. Most commonly isolated bacterium, Staphylococcus aureus was most often sensitive to Moxifloxacin, Imipenem/Meropenem, Vancomycin and Linezolid, while majority isolated gram negative rods were sensitive to Imipenem/Meropenem, Piperacillin-Tazobactam and Ticarcillin-Clavulanate. (author)

  18. Bacterial agents and antibiotic sensitivity in children with urinary infection in two hospitals of Popayan, Colombia

    Directory of Open Access Journals (Sweden)

    Carolina Álvarez-Czeczotta

    2012-06-01

    Full Text Available Introduction: Urinary Tract Infection (UTI is a common condition in children. Isolation of bacteria and early management is a priority in order to contribute to the reduction of morbidity and avoid bacterial resistance. Objectives: To identify bacterial etiologic agents and antibiotic sensitivity in children (1 month to 5 years of age with UTI in two hospitals of Popayán, Colombia. Materials and methods: We conducted a cross-sectional study in children aged 1 month to 5 years of age who consulted the emergency services of two hospitals with clinical suspicion of UTI. The sample was 123 children. Using an instrument collected demographic variables, signs and symptoms, results of urinalysis, urine culture, sensitivity testing, treatment, and UTI classification. We determined the frequency and proportions of sociodemographic and clinical variables, bacterial agents and antibiotic resistance. Data was analyzed using SPSS 11.5 program. Results: We included 129 children diagnosed with UTI with positive urine culture, bladder catheter taken with 97.7% of cases. 74.8% of patients were female. Escherichia coli was the seed that was isolated more frequently (95.4%, then Sp Proteus (2.4%, and Klebsiella pneumoniae (1.6%. The antibiotics to which the bacteria showed adequate sensitivity were: ceftriaxone, amikacin, gentamicin, ciprofloxacin, nitrofurantoin, cefuroxime and cephalexin. Showed low sensitivity: ampicillin and trimethoprim sulfa. Conclusions: Escherichia coli was the bacteria that cause of UTI in our study population. For initial empiric treatment of hospitalized patients would recommend parenteral drug third generation cephalosporins (ceftriaxone and aminoglycosides (amikacin, gentamicin. For outpatient management, oral antibiotics showed greater sensitivity were nalidixic acid, cefuroxime and cephalexin.

  19. Injudicious Provision of Subtherapeutic Doses of Antibiotics in Community Pharmacies

    Directory of Open Access Journals (Sweden)

    Mohamed E Amin

    2017-02-01

    Results: The simulated client visited 104 pharmacies and was sold an antibiotic at 68 pharmacies in total. A cold group with one or more antibiotic pills was provided in 31 pharmacies. Upon request for two antibiotic pills, 2-8 antibiotic pills were provided in 30 pharmacies whereas an antibiotic carton was provided in three pharmacies. In four pharmacies, the simulated client was sold a cold group containing an antibiotic as well as another antibiotic upon request. Beta-lactam antibiotics comprised 76% of antibiotics provided. In five encounters, the simulated client was told that the cold group contained an antibiotic when, in fact, it did not. Conclusions: Subtherapeutic doses of antibiotics are provided at dangerous rates in Alexandria’s community pharmacies. Interventions are urgently needed to tackle different factors contributing to this dangerous practice. Conflict of Interest We declare no conflicts of interest or financial interests that the authors or members of their immediate families have in any product or service discussed in the manuscript, including grants (pending or received, employment, gifts, stock holdings or options, honoraria, consultancies, expert testimony, patents and royalties   Type: Original Research

  20. Survival of Antibiotic Resistant and Antibiotic Sensitive Strains of E. coli O157 and E. coli O26 in Food Matrices.

    OpenAIRE

    Walsh, Ciara; Duffy, Geraldine; Blair, I. S.; McDowell, D. A.

    2006-01-01

    Escherichia coli O157:H7 or E. coli O26, which were AS (antibiotic sensitive), AR (laboratory created antibiotic resistant mutants), or naturally MAR (multi-antibiotic resistant), were inoculated into laboratory media, yoghurt or orange juice and their growth/survival monitored during enrichment at 37 °C or storage at 4 °C. The strains were also inoculated into minced beef and their thermal inactivation (D-values) examined at 55 °C, with and without a prior heat shock at 48 °C. The growth kin...

  1. Investigation of colistin sensitivity via three different methods in Acinetobacter baumannii isolates with multiple antibiotic resistance.

    Science.gov (United States)

    Sinirtaş, Melda; Akalin, Halis; Gedikoğlu, Suna

    2009-09-01

    In recent years there has been an increase in life-threatening infections caused by Acinetobacter baumannii with multiple antibiotic resistance, which has lead to the use of polymyxins, especially colistin, being reconsidered. The aim of this study was to investigate the colistin sensitivity of A. baumannii isolates with multiple antibiotic resistance via different methods, and to evaluate the disk diffusion method for colistin against multi-resistant Acinetobacter isolates, in comparison to the E-test and Phoenix system. The study was carried out on 100 strains of A. baumannii (colonization or infection) isolated from the microbiological samples of different patients followed in the clinics and intensive care units of Uludağ University Medical School between the years 2004 and 2005. Strains were identified and characterized for their antibiotic sensitivity by Phoenix system (Becton Dickinson, Sparks, MD, USA). In all studied A. baumannii strains, susceptibility to colistin was determined to be 100% with the disk diffusion, E-test, and broth microdilution methods. Results of the E-test and broth microdilution method, which are accepted as reference methods, were found to be 100% consistent with the results of the disk diffusion tests; no very major or major error was identified upon comparison of the tests. The sensitivity and the positive predictive value of the disk diffusion method were found to be 100%. Colistin resistance in A. baumannii was not detected in our region, and disk diffusion method results are in accordance with those of E-test and broth microdilution methods.

  2. Aerobic vaginal pathogens and their sensitivity pattern.

    Science.gov (United States)

    Mumtaz, Shamim; Ahmad, Mumtaz; Aftab, Irum; Akhtar, Naeem; ul Hassan, Masood; Hamid, Abdul

    2008-01-01

    the groups of carbapenems and beta-lactams beta-lactamase inhibitor combinations. The high prevalence of gynaecological infections demands that the patients with gynaecological symptoms be investigated thoroughly. Culture must invariably be done. Currently the antibiotics showing good sensitivity are very expensive. So there is a need for an effective antimicrobial policy. Effective drug should be reserved for the treatment of serious life threatening situations only.

  3. Use of antibiotics by primary care doctors in Hong Kong

    Directory of Open Access Journals (Sweden)

    Lam Tai

    2009-05-01

    Full Text Available Abstract Objectives To determine the use of antibiotics by primary care doctors. Methods General practitioners in Hong Kong were invited to fill in a short questionnaire on every patient with infection that they had seen on the first full working day once every three months for four consecutive quarters starting from December 2005. Results Forty six primary care doctors took part and a total of 3096 completed questionnaires were returned. The top three diagnoses were upper respiratory tract infection (46.7%, gastrointestinal infection (8.2% and pharyngitis (7.1%. Thirty percent of patient encounters with infections were prescribed antibiotics but only 5.2% of patient encounters with upper respiratory tract infection (URTI were prescribed antibiotics. Amino-penicillins were the most commonly used antibiotics while beta-lactam/beta-lactamase inhibitor combinations (BLBLIs were the second most commonly used antibiotics and they accounted for 16.5% and 14.0% of all antibiotics used respectively. Of all patients or their carers, those who demanded or wished for antibiotics were far more likely to be prescribed antibiotics (Pearson chi-square test, p Conclusion The antibiotic prescribing patterns of primary care doctors in Hong Kong are broadly similar to primary care doctors in other developed countries but a relatively low rate of antibiotics is used for URTI.

  4. Re-sensitizing drug-resistant bacteria to antibiotics by designing Antisense Therapeutics

    Science.gov (United States)

    Courtney, Colleen; Chatterjee, Anushree

    2014-03-01

    ``Super-bugs'' or ``multi-drug resistant organisms'' are a serious international health problem, with devastating consequences to patient health care. The Center for Disease Control has identified antibiotic resistance as one of the world's most pressing public health problems as a significant fraction of bacterial infections contracted are drug resistant. Typically, antibiotic resistance is encoded by ``resistance-genes'' which express proteins that carryout the resistance causing functions inside the bacterium. We present a RNA based therapeutic strategy for designing antimicrobials capable of re-sensitizing resistant bacteria to antibiotics by targeting labile regions of messenger RNAs encoding for resistance-causing proteins. We perform in silico RNA secondary structure modeling to identify labile target regions in an mRNA of interest. A synthetic biology approach is then used to administer antisense nucleic acids to our model system of ampicillin resistant Escherichia coli. Our results show a prolonged lag phase and decrease in viability of drug-resistant E. colitreated with antisense molecules. The antisense strategy can be applied to alter expression of other genes in antibiotic resistance pathways or other pathways of interest.

  5. Antibiotic sensitivity pattern of uropathogens from pregnant women with urinary tract infection in Abakaliki, Nigeria.

    Science.gov (United States)

    Onoh, Rc; Umeora, Ouj; Egwuatu, Ve; Ezeonu, Po; Onoh, Tjp

    2013-01-01

    Urinary tract infection (UTI) is a common bacterial infection during pregnancy and a significant cause of perinatal and maternal morbidity and mortality. The causative bacteria have remained virtually the same although with variations in individual prevalence. There has been an increasing resistance by these bacteria to the commonly available antibiotics. To determine the prevalence of UTI, the common causative bacteria, and their antibiotic sensitivity pattern among pregnant women with UTI. This is a descriptive study that was carried out at the Obstetrics Department of two tertiary institutions in Abakaliki, Ebonyi State, Nigeria (Federal Medical Center and Ebonyi State University Teaching Hospital) over a period of 12 months. Midstream urine specimens from selected pregnant women with clinical features of UTI were collected for microscopy, culture, and sensitivity. The results were analyzed with the 2008 Epi Info™ software. A total of 542 pregnant women presented with symptoms of UTI and were recruited for the study over the study period. Of the 542 pregnant women, 252 (46.5%) had significant bacteriuria with positive urine culture and varying antibiotic sensitivity pattern. The prevalence of symptomatic UTI was 3%. Escherichia coli was the most common bacteria isolated with a percentage of 50.8%. Other isolated micro organisms included Stapylococcus aereus (52 cultures, 20.6%), Proteus mirabilis (24 cultures, 9.5%), S. saprophyticus (18 cultures, 7.1%), Streptococcus spp. (14 cultures, 5.6%), Citrobacter spp. (5 cultures, 2.0%), Klebsiella spp. (4 cultures, 1.6%), Enterobacter spp. (4 cultures, 1.6%), and Pseudomonas spp. (3 cultures, 1.2%). Levofloxacin had the highest overall antibiotic sensitivity of 92.5%. Others with overall antibiotic sensitivity pattern greater than 50% included cefpodoxime (87.3%), ofloxacin (77.4%), ciprofloxacin (66.7%), ceftriaxone (66.7%), and gentamicin (50.8%). E. coli was the most common etiological agent of UTI in pregnancy

  6. In vitro activity and stability against novel beta-lactamases of investigational beta-lactams (cefepime, cefpirome, flomoxef, SCE2787 and piperacillin plus tazobactam) in comparison with established compounds (cefotaxime, latamoxef and piperacillin).

    Science.gov (United States)

    Bauernfeind, A; Schweighart, S; Eberlein, E; Jungwirth, R

    1991-01-01

    The therapeutic perspectives of flomoxef, SCE 2787, cefpirome, cefepime, latamoxef, cefotaxime and of piperacillin plus tazobactam were comparatively evaluated by their in vitro activity against 1119 clinical isolates of 83 bacterial species. Escherichia coli, Klebsiella spp. Enterobacter sakazakii, Proteus spp. and Shigella spp. were about equally susceptible to the cephalosporins (MIC90: 0.06 to 0.5 mg/l), while the MIC90 for piperacillin plus tazobactam was between 2 and 16 mg/l. Enterobacter cloacae, Enterobacter aerogenes and Serratia spp. were most susceptible to SCE 2787, cefpirome and cefepime (MIC90: 0.06 to 2 mg/l) followed by latamoxef, cefotaxime, flomoxef and piperacillin plus tazobactam. For Citrobacter spp., Providencia spp. and Yersinia enterocolitica MIC90 were between 0.06 and 0.5 mg/l. Flomoxef was between 2 to 4 log2 less active against these species but more active than piperacillin plus tazobactam (MIC90: 2 and 8 mg/l). Morganella morganii and Hafnia alvei were most susceptible to cefepime, cefpirome and latamoxef (MIC90: 0.13 to 0.5 mg/l) while cefotaxime (MIC90: 8 mg/l) and piperacillin plus tazobactam (MIC90: 8 and greater than 64 mg/l) were the least active compounds. SCE 2787, cefepime and cefpirome were the most potent beta-lactams against the majority of the 13 species of non-fermentative bacilli (NFB) investigated (MIC90: 0.5 to 16 mg/l). The oxacephems were the least active compounds against NFB. Cefepime was the most active of the compounds included against Pseudomonas aeruginosa (MIC90: 16 mg/l). Haemophilus spp., Neisseria gonorrhoeae and Bordetella pertussis were most susceptible to cefotaxime (MIC90: 0.03 to 0.06 mg/l). Latamoxef had the lowest activity of all compounds against gram-positive cocci. Flomoxef was the most active compound against penicillinase producing Staphylococcus aureus and about equally active as the other betalactams against methicillin susceptible staphylococci of other staphylococcal species

  7. Epidemiology and antibiotic sensitivity of Staphylococcus aureus nasal carriage in children in Hungary.

    Science.gov (United States)

    Laub, Krisztina; Tóthpál, Adrienn; Kardos, Szilvia; Dobay, Orsolya

    2017-03-01

    The aim of this study was to assess the Staphylococcus aureus nasal carriage rate in healthy children all over Hungary and to specify some risk factors, the antibiotic resistance patterns of the bacteria, and their genetic relatedness. In total, 878 children (aged 3-6 years) were screened at 21 day-care centers in 16 different cities in Hungary, between February 2009 and December 2011. Samples taken from both nostrils were cultured on blood agar, and suspected S. aureus isolates were identified by β-hemolysis, catalase positivity, clump test, and nucA PCR. Methicillin-resistant strains were screened by mecA and mecC PCR. Antibiotic susceptibility was determined by agar dilution or gradient test strips. Pulsed-field gel electrophoresis was used for genotyping. S. aureus carriage rate was found to be 21.3%, which correlates well with international data. We found no statistically significant correlation between the gender or the sibling status and S. aureus carriage. All isolates were sensitive to oxacillin, trimethoprim-sulfamethoxazole, and mupirocin. The resistance rates for erythromycin, ciprofloxacin, clindamycin, gentamicin, and tetracycline were 7.5%, 0.5%, 1.1%, 3.7%, and 4.3%, respectively. The isolates showed very high genetic diversity. In summary, carried S. aureus isolates are more sensitive to antibiotics compared with clinical isolates in Hungary, and methicillin-resistant S. aureus carriage rate is very low yet.

  8. Antibiotic sensitivity pattern of bacteria from diabetic foot infections Haji Adam Malik central general hospital

    Science.gov (United States)

    Bulolo, B. A.; Pase, M. A.; Ginting, F.

    2018-03-01

    Increasing rate of Diabetic Foot Infections (DFIs) caused by multi-drug-resistance pathogens plays a huge role in the duration of hospitalization, morbidity, and mortality of diabetic patients. The aim of the study is to assess the antibiotic sensitivity pattern of bacteria in DFIs and causative microorganisms. Using cross-sectional retrospective study, data were collected from medical records of DFIs patients previously hospitalized atHaji Adam Malik Hospital, Medan from January to July 2017. 33 patients met the criteria and got enrolled in the study. The classification of DFIs was evaluated according to Wagner’s Classification. Evaluation of antibiotic sensitivity and identification of causative microorganisms were performed in standard microbiologic methods. The most common grade of DFIs was Grade-4 (48.5%), followed by Grade-3 (39.4%) and Grade-5 (9.1%). A total of 12 pathogens were identified. The most common infecting microorganism isolated on pus cultures was Klebsiella pneumonia (33.3%), followed by Escherichia coli (24.2%), Acinetobacter baumanni (12.1%), and Staphylococcus aureus (9.1%). Frequent susceptible antibiotics were Amikacin (88.8%), Imipenem (87%), Meropenem (84.6%), Erythromycin (75%), and Cefoperazone/Sulbactam (68.9%). DFIs are polymicrobial infections in this study K. pneumonia was the most common cause microorganism.

  9. An international multicenter study of antimicrobial consumption and resistance in Staphylococcus aureus isolates from 15 hospitals in 14 countries

    DEFF Research Database (Denmark)

    Westh, Henrik Torkil; Zinn, Christina Scheel; Rosdahl, Vibeke Thamdrup

    2004-01-01

    of therapeutical subgroups of antimicrobials varied significantly between hospitals. A positive correlation was found between S. aureus resistance to methicillin (MRSA) and consumption of beta-lactam combinations, between resistance to quinolones and consumption of beta-lactam combinations and carbapenems....... Consumption of beta-lactamase-sensitive antibiotics (penicillin) was positively correlated to consumption of beta-lactamase-resistant penicillins and negatively correlated to consumption of carbapenems, quinolones, and glycopeptides, whereas consumption of cephalosporins was positively correlated...

  10. SENSITIVITY TO ANTIBIOTICS, ANTISEPTICAL NOSOCOMIAL PSEUDOMONAS AERUGINOSA, ISOLATED IN UROLOGICAL PATIENTS

    Directory of Open Access Journals (Sweden)

    Rymsha E.V.

    2015-05-01

    Full Text Available Introduction. Given the active introduction into clinical practice of new groups of antibiotics and antiseptics, the problem of treatment of purulent-inflammatory complications after prostatectomy and today is relevant. Of particular concern belated cases of diagnosis and treatment of postoperative complications in urological practice patients receiving antibiotic therapy The use of traditional antibiotics is not prevents the development of infection, because the problem of resistance of microorganisms to antibiotics and antiseptics remains relevant. The solution to the problem of development of infectious complications and prevent the formation of resistant clinical strains largely depends on the isolated pathogen, susceptibility to antimicrobial agents based on its bioavailability , ability to spread and penetrate into cells and tissues, selection of dose, interval, and route of administration to maintain minimum bactericidal concentration Material and methods. The study involved 145 patients who were treated in the urology Department of the Vinnytsia regional clinical hospital named of M. I. Pirogov. Patients underwent the surgical treatment of benign hypertrophic prostate. Material for bacteriological studies of purulent-inflammatory diseases were urine, pieces of the prostate, remote operationally, urinary catheters, through which conducted irrigation of the bladder. Specimen collection, transportation was carried out in accordance with modern requirements. Identification was done by morphological, cultural and biochemical properties. The definition of antibiotic resistance were performed according to "guidelines for the definition of sensitivity of microorganisms to antibiotics by the method of diffusion in agar using discs" (No. 2675-83, Kiev, 2007 12 .]. Evaluation of the results of determining the sensitivity of microorganisms to antibiotics was carried out on the basis of the determination of the zone of growth (mm of the studied

  11. Antibiotic sensitivity and resistance in children with urinary tract infection in Sanliurfa.

    Science.gov (United States)

    Abuhandan, Mahmut; Güzel, Bülent; Oymak, Yeşim; Çiftçi, Halil

    2013-06-01

    This study aimed to evaluate antibiotic resistance in the province of Şanliurfa and to observe any difference between antibiotic resistance rates. The study comprised 107 children who presented at the pediatric polyclinic with complaints of urinary tract infection with the diagnosis of urinary tract infection and whose urine cultures exhibited bacterial growth. The patients were analyzed with respect to the frequency of proliferating pathogens, sensitivity to the antibiotics used and the rates of developed resistance to the antibiotics. A total of 107 patients aged between 1 year and 15 years were included in the study, encompassing 14 (13.1%) males and 93 (86.9%) females. According to the urine culture results, proliferation of Escherichia coli (E. coli) was observed in 69 (64.5%), Klebsiella spp. in 13 (12.1%), Proteus mirabilis in 9 (8.4%), Staphylococcus aureus in 5 (4.7%), Pseudomonas aeruginosa in 5 (4.7%), Acinetobacter spp. in 3 (2.8%) and Enterococcus spp. in 3 (2.8%) patients. For proliferating E. coli, high resistance rates to ceftriaxone (39.5%), nitrofurantoin (19.7%), ampicillin-sulbactam (64.1%), co-trimoxazole (41.5%), amoxicillinclavulanate (51.7%) and cefuroxime (38.1%) were observed. All of isolated microorganisms were resistant to ampicillin-sulbactam, amoxicillin-clavulanate, co-trimoxazole, ceftriaxone, cefuroxime and cefoxitin in decreasing frequencies. The most effective antimicrobial agents were determined to be imipenem, sulpera-zone, quinolone and aminoglycosides. In our region, parenteral antibiotics that should be selected for the empirical treatment of UTIs in all age groups are the aminoglycosides and 3(rd) generation cephalosporines. In contrast to other studies, these results suggest that co-trimoxazole should be used for children aged 0-1, and 2(nd) generation cephalosporins should be used for the oral treatment of children aged 1-5 due to the low rate of resistance to nitrofurantoin in patients aged over 5 years.

  12. Prevalence of enteropathogens and their antibiotic sensitivity pattern in puppies with hemorrhagic gastroenteritis

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    A. Kokila Priya

    2017-08-01

    Full Text Available Aim: Hemorrhagic gastroenteritis (HGE ranging from mild to severe forms is commonly encountered in puppies. The aim of the study was to identify the prevalence of common enteropathogens and the antibiotic sensitivity pattern in puppies reported with HGE. Materials and Methods: The canine HGE activity index, with little modification, was adopted to identify Grade III/ severely affected puppies below 6 months of age. Fecal polymerase chain reaction (PCR assay was employed to screen and compare the enteropathogens in puppies with hemorrhagic diarrhea and healthy control. Results: Canine parvovirus 2b was identified in 90.3% of the diarrheic and 10% of the non-diarrheic healthy puppies. Clostridium difficile was identified in all the diarrheic puppies and in 80% of the healthy puppies. Among the diarrheic puppies, 17.7% were positive for Clostridium perfringens enterotoxin, 9.7% were positive for C. perfringens alpha toxin, 6.4% were positive for Escherichia coli shiga toxin, 6.4% were positive for E. coli enterotoxin (LT, and 3.2% were positive for canine distemper virus. Whereas, none of the healthy puppies were positive for these bacteria and toxins. Fecal antibiotic sensitivity test pattern revealed gentamicin to be sensitive in 95% of the cases, azithromycin in 50%, enrofloxacin in 25%, cefotaxime in 20%, and tetracycline in 5% of the cases. Conclusion: Parvoviral enteritis is predominant among puppies. Yet, bacteria and their toxins also play an important role in HGE. Gentamicin has higher sensitivity against the enteropathogens associated with the condition.

  13. Bacterial pattern and antibiotic sensitivity in children and adolescents with infected atopic dermatitis

    Science.gov (United States)

    Samosir, C. T.; Ruslie, R. H.; Rusli, R. E.

    2018-03-01

    Atopic dermatitis (AD) is a pruritic and chronic inflammatory skin disease which affected approximately 20% in children. Bacterial infection is common in AD patients and correlates directly with AD severity. A cross-sectional study was conducted to evaluate the prevalence of bacterial skin infection in AD patients and its relation with severity of AD and also to study bacteria in the infected AD and its antibiotic sensitivity. Samples were 86 children and adolescents with an AD in Helvetia Community Health Center Medan from March 2016 until February 2017. Index of SCORing Atopic Dermatitis (SCORAD) was used to evaluate the severity of AD. Lesion and nonlesional skinwere swabbed to take sterile cultures. All bacteria noted and tested for antibiotic sensitivity. Datawere by using Chi-Square and Mann Whitney test with 95% CI and p-value<0.05 was considered statistically significant. Fifty-six AD patients (65.1%) were bacterial infected. There was a significant relationship between severity of AD and bacterial infection (p = 0.006). Staphylococcus aureus was the leading bacteria from all degrees of AD severity. Isolated Staphylococcus aureuswas sensitive to amoxicillin-clavulanate (93.3%), clindamycin (90%), erythromycin (90%), and gentamicin (90%), while sensitivity to tetracycline was low (20%).

  14. BACTERIAL PROFILE, ANTIBIOTIC SENSITIVITY AND RESISTANCE OF LOWER RESPIRATORY TRACT INFECTIONS IN UPPER EGYPT

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    Gamal Agmy

    2013-09-01

    Full Text Available BACKGROUND: Lower respiratory tract infections (LRTI account for a considerable proportion of morbidity and antibiotic use. We aimed to identify the causative bacteria, antibiotic sensitivity and resistance of hospitalized adult patients due to LRTI in Upper Egypt. METHODS: A multicentre prospective study was performed at 3 University Hospitals for 3 years. Samples included sputum or bronchoalveolar lavage (BAL for staining and culture, and serum for serology. Samples were cultured on 3 bacteriological media (Nutrient, Chocolate ,MacConkey's agars.Colonies were identified via MicroScan WalkAway-96. Pneumoslide IgM kit was used for detection of atypical pathogens via indirect immunofluorescent assay. RESULTS: The predominant isolates in 360 patients with CAP were S.pneumoniae (36%, C. pneumoniae (18%, and M. pneumoniae (12%. A higher sensitivity was recorded for moxifloxacin, levofloxacin, macrolides, and cefepime. A higher of resistance was recorded for doxycycline, cephalosporins, and β-lactam-β-lactamase inhibitors. The predominant isolates in 318 patients with HAP were, methicillin-resistant Staphylococcus aureus; MRSA (23%, K. pneumoniae (14%, and polymicrobial in 12%. A higher sensitivity was recorded for vancomycin, ciprofloxacin, and moxifloxacin. Very high resistance was recorded for β-lactam-β-lactamase inhibitors and cephalosporins. The predominant organisms in 376 patients with acute exacerbation of chronic obstructive pulmonary diseases (AECOPD were H. influnzae (30%, S. pneumoniae (25%, and M. catarrhalis(18%. A higher sensitivity was recorded for moxifloxacin, macrolides and cefepime. A higher rate of resistance was recorded for aminoglycosides and cephalosporins CONCLUSIONS: The most predominant bacteria for CAP in Upper Egypt are S. pneumoniae and atypical organisms, while that for HAP are MRSA and Gram negative bacteria. For acute exacerbation of COPD,H.influnzae was the commonest organism. Respiratory quinolones

  15. RESEARCH IN SENSITIVITY TO ANTIBIOTICS, ANTISEPTICS IN PSEUDOMONAS AERUGINOSA STRAINS ISOLATED FROM PATIENTS WITH INFECTIOUS COMPLICATIONS

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    O. A. Nazarchuk

    2017-07-01

    Full Text Available Background. Infections caused by Pseudomonas are one of the topical issues of medicine. Objective. The aim of the research was to study sensityvity to antibiotics, antiseptics of P. aeruginosa clinical strains that cause infectious complications in patients with burns. Methods. Microbiological study of biological material, received from 435 patients with burns of the 3rd-4th stages (2011-2015 years. In early terms of burn disease 127 clinical strains of P. aeruginosa were isolated from patients. Standard methods were used to identify clinical isolates of P. aeruginosa by their morphological, tinctirial, culture and biochemical properties. The research of antimicrobial action of antiseptics, antibiotics against Pseudomonas were carried out by means of standard methods according to the Directive of the Ministry of Health of Ukraine (No. 167 from 05.04.2007 р. and guidelines of National Committee of Clinical and Laboratory Study (NCCLS, 2002. Results. It was established that P. aeruginosa caused infectious complications in 23.9% of patients among other pathogens. Clinical isolates of P. aeruginosa were found to be low sensitive to amoxicillin/clavulanate (30.76%, ceftazidime (25.92%, cefoperazonum/sulbactam (46.15%, aztreonam (51.85%, tobramycin (38.46%, amicacin (70.34%, doxiciclini (26.92%, fluoroquinolones (59.26%. The analitical progistic criteria of decrease of sensitivity to ceftazidime, cefepim, meropenem and gatifloxacin were found in P. aeruginosa. This pathogen was determined to be sensitive to decasan ®, antimicrobial composition of decamethoxine ®, iodine pvidone. Conclusions. Clinical strains of Pseudomonas aeruginosa, being highly resistant to antibiotics, are also very sensitive to antiseptics decasan ®, antimicrobial of decamethoxine®, povidone iodine.

  16. Bacterial Species and Antibiotic Sensitivity in Korean Patients Diagnosed with Acute Otitis Media and Otitis Media with Effusion.

    Science.gov (United States)

    Kim, Sang Hoon; Jeon, Eun Ju; Hong, Seok Min; Bae, Chang Hoon; Lee, Ho Yun; Park, Moo Kyun; Byun, Jae Yong; Kim, Myung Gu; Yeo, Seung Geun

    2017-04-01

    Changes over time in pathogens and their antibiotic sensitivity resulting from the recent overuse and misuse of antibiotics in otitis media (OM) have complicated treatment. This study evaluated changes over 5 years in principal pathogens and their antibiotic sensitivity in patients in Korea diagnosed with acute OM (AOM) and OM with effusion (OME). The study population consisted of 683 patients who visited the outpatient department of otorhinolaryngology in 7 tertiary hospitals in Korea between January 2010 and May 2015 and were diagnosed with acute AOM or OME. Aural discharge or middle ear fluid were collected from patients in the operating room or outpatient department and subjected to tests of bacterial identification and antibiotic sensitivity. The overall bacteria detection rate of AOM was 62.3% and OME was 40.9%. The most frequently isolated Gram-positive bacterial species was coagulase negative Staphylococcus aureus (CNS) followed by methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), and Streptococcus pneumonia (SP), whereas the most frequently isolated Gram-negative bacterium was Pseudomonas aeruginosa (PA). Regardless of OM subtype, ≥ 80% of CNS and MRSA strains were resistant to penicillin (PC) and tetracycline (TC); isolated MRSA strains showed low sensitivity to other antibiotics, with 100% resistant to PC, TC, cefoxitin (CFT), and erythromycin (EM); and isolated PA showed low sensitivity to quinolone antibiotics, including ciprofloxacin (CIP) and levofloxacin (LFX), and to aminoglycosides. Bacterial species and antibiotic sensitivity did not change significantly over 5 years. The rate of detection of MRSA was higher in OME than in previous studies. As bacterial predominance and antibiotic sensitivity could change over time, continuous and periodic surveillance is necessary in guiding appropriate antibacterial therapy. © 2017 The Korean Academy of Medical Sciences.

  17. Mannitol enhances antibiotic sensitivity of persister bacteria in Pseudomonas aeruginosa biofilms.

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    Nicolas Barraud

    Full Text Available The failure of antibiotic therapies to clear Pseudomonas aeruginosa lung infection, the key mortality factor for cystic fibrosis (CF patients, is partly attributed to the high tolerance of P. aeruginosa biofilms. Mannitol has previously been found to restore aminoglycoside sensitivity in Escherichia coli by generating a proton-motive force (PMF, suggesting a potential new strategy to improve antibiotic therapy and reduce disease progression in CF. Here, we used the commonly prescribed aminoglycoside tobramycin to select for P. aeruginosa persister cells during biofilm growth. Incubation with mannitol (10-40 mM increased tobramycin sensitivity of persister cells up to 1,000-fold. Addition of mannitol to pre-grown biofilms was able to revert the persister phenotype and improve the efficacy of tobramycin. This effect was blocked by the addition of a PMF inhibitor or in a P. aeruginosa mutant strain unable to metabolise mannitol. Addition of glucose and NaCl at high osmolarity also improved the efficacy of tobramycin although to a lesser extent compared to mannitol. Therefore, the primary effect of mannitol in reverting biofilm associated persister cells appears to be an active, physiological response, associated with a minor contribution of osmotic stress. Mannitol was tested against clinically relevant strains, showing that biofilms containing a subpopulation of persister cells are better killed in the presence of mannitol, but a clinical strain with a high resistance to tobramycin was not affected by mannitol. Overall, these results suggest that in addition to improvements in lung function by facilitating mucus clearance in CF, mannitol also affects antibiotic sensitivity in biofilms and does so through an active, physiological response.

  18. Evaluation of effect of high frequency electromagnetic field on growth and antibiotic sensitivity of bacteria.

    Science.gov (United States)

    Salmen, Saleh H; Alharbi, Sulaiman A; Faden, Asmaa A; Wainwright, M

    2018-01-01

    This study was aimed to evaluate the impact of high frequency electromagnetic fields (HF-EMF at 900 and 1800 MHz) on DNA, growth rate and antibiotic susceptibility of S. aureus , S. epidermidis , and P. aeruginosa . In this study, bacteria were exposed to 900 and 1800 MHz for 2 h and then inoculated to new medium when their growth rate and antibiotic susceptibility were evaluated. Results for the study of bacterial DNA unsuccessful to appearance any difference exposed and non-exposed S. aureus and S. epidermidis . Exposure of S. epidermidis and S. aureus to electromagnetic fields mostly produced no statistically significant decrease in bacterial growth, except for S. aureus when exposure to 900 MHz at 12 h. Exposure of P. aeruginosa to electromagnetic fields at 900 MHz however, lead to a significant reduction in growth rate, while 1800 MHz had insignificant effect. With the exception of S. aureus , treated with amoxicillin (30 µg) and exposed to electromagnetic fields, radiation treatment had no significant effect on bacterial sensitivity to antibiotics.

  19. Celecoxib sensitizes Staphylococcus aureus to antibiotics in macrophages by modulating SIRT1.

    Science.gov (United States)

    Annamanedi, Madhavi; Kalle, Arunasree M

    2014-01-01

    We have previously shown that celecoxib in combination with an antibiotic, increase the bacterial sensitivity to antibiotics. However, the underlying molecular mechanism remained elusive. Efficacy of the combinatorial treatment of celecoxib and ampicillin in vitro was evaluated on macrophage-phagocytosed S. aureus. To elucidate the mechanism, signaling pathway of infection and inflammation involving TLR2, JNK, SIRT1 and NF-κB was studied by FACS, Western blot, ELISA and activity assays. Combinatorial treatment of ampicillin and celecoxib reduced the bacterial load in the macrophages. Further studies clearly suggested the activation of the master regulator of oxidative stress and inflammation SIRT1, by celecoxib when used alone and/or in combination with ampicillin. Also, the results indicated that celecoxib inhibited JNK phosphorylation thereby stabilizing and activating SIRT1 protein that inhibited the COX-2 gene transcription with a significant decrease in the levels of protein inflammatory cytokines like IL-6, MIP-1α and IL-1β via inhibition of NF-κB. SIRT1 activation by celecoxib also resulted in increase of catalase and peroxidase activity with a decrease in Nitric oxide levels. In conclusion, we demonstrate a novel role of celecoxib in controlling inflammation as an enhancer of antibiotic activity against bacteria by modulating SIRT1.

  20. Can a simple urinalysis predict the causative agent and the antibiotic sensitivities?

    Science.gov (United States)

    Waseem, Muhammad; Chen, Justin; Paudel, Govinda; Sharma, Nirdesh; Castillo, Manuel; Ain, Yumna; Leber, Mark

    2014-04-01

    The objective of this study was (1) to determine the reliability of urinalysis (UA) for predicting urinary tract infection (UTI) in febrile children, (2) to determine whether UA findings can predict Escherichia coli versus non-E. coli urinary tract infection, and (3) to determine if empiric antibiotics should be selected based on E. coli versus non-E. coli infection predictions. This was a retrospective chart review of children from 2 months to 2 years of age who presented to the emergency department with fever (rectal temperature >100.4°F) and had a positive urine culture. This study was conducted between January 2004 and December 2007. Negative UA was defined as urine white blood cell count less than 5 per high-power field, negative leukocyte esterase, and negative nitrites. Urine cultures were classified into E. coli and non-E. coli groups. These groups were compared for sex, race, and UA findings. Multivariate forward logistic regression, using the Wald test, was performed to calculate the likelihood ratio (LR) of each variable (eg, sex, race, UA parameters) in predicting UTI. In addition, antibiotic sensitivities between both groups were compared. Of 749 medical records reviewed, 608 were included; negative UA(-) was present in 183 cases, and positive UA(+) was observed in 425 cases. Furthermore, 424 cases were caused by E. coli, and 184 were due to non-E. coli organisms. Among 425 UA(+) cases, E. coli was identified in 349 (82.1%), whereas non-E. coli organisms were present in 76 (17.9%); in contrast, in 183 UA(-) cases, 108 (59%) were due to non-E. coli organisms versus 75 (41%), which were caused by E. coli. Urinalysis results were shown to be associated with organism group (P Antibiotic sensitivity compared between UA groups demonstrated equivalent superiority of cefazolin (94.7% sensitive in UA(+) vs 84.0% in UA(-) group; P sensitivity to trimethoprim-sulfamethoxazole (82.2% vs 71.3% in UA(+); P = 0.008). Urinalysis is not an accurate predictor of UTI. A

  1. Investigations of sensitivity to antibiotics of salmonella strain species originating from poultry from different epizootiological areas

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    Stošić Zorica

    2006-01-01

    Full Text Available A total of 1666 samples were examined, of which 512 samples of parenchymatous organs of dead or deliberately sacrtificed animals, 60 samples of non-hatched fertilized eggs, 202 samples of feces, 652 samples of cloacal smears, 221 samples of smears from walls of maintenance objects, incubator stations, and transport vehicles, 19 samples of beddings and shavings. The samples originated from poultry farms and which were taken to a laboratory immediately on sampling and sown the same day. A total of 104 strains of Salmonella were isolated: 94 strains from samples of parenchymatous organs of dead chicks, 1 strain from non-hatched eggs, 3 strains from feces samples, 1 strain from samples of cloacal smears, 4 strains from samples of surface smears of maintenance objects and transport vehicles, and 1 strain from samples of beddings and shavings. Serological typization established the presence of the following serovarieties: Salmonella Enteritidis 79 strains, Salmonella Hartford 17 strains, Salmonella Typohimurium 5 strains, Salmonella Mbandaka 2 strains, and Salmonella Glostrup 1 strain. We examined the sensitivity of Salmonella strains to ampicillin, amoxicillin, gentamycin, streptomycin, neomycin, enrofloxacine, norfloxacine, flumequin, erythromycin, lincospectin, colistin, fluorphenicol, and a combination of sulphamethoxasole and trimethoprim. In S. Enteritidis strains, no resistence was established to colistin, fluorphenicol and sulphamethoxasole+trimethoprim, in fact, the sensitivity to these antibiotics and chemotherapeutics was 100%. Prevalence resitence of 0.96%, in only one strain, was established for enrofloxacine. A high prevalence resistence of 33.6% was established for neomycin, while prevalence resistence of 3.86% was established for the related aminoglycozide antibiotic gentamycin. The highest prevalence resistance in S.Hartford strains was established for erythromycin, 15.38%, and streptomycin, 7.6%. Resistence of S. Tyohimurium was

  2. The clinical spectrum and antibiotic sensitivity patterns of staphylococcal pyodermas in the community and hospital

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    Shireen Furtado

    2014-01-01

    Full Text Available Context: The uncontrolled use of antibiotics has resulted in a relentless spread of multiresistant strains of Staphylococcus aureus. There are studies conducted in medical colleges in Chandigarh, Chennai, Mumbai and Vellore comparing pyodermas in the community and hospital setting based on clinical and bacteriological parameters. Aims: This study, conducted over 1½ years from March 2009 to August 2010, aimed at analyzing the clinical spectrum and antibiotic sensitivity pattern of community and hospital-associated (HA staphylococcal pyoderma. It also assessed the prevalence of methicillin-resistant S. aureus (MRSA in the community and hospital cohort settings. Subjects and Methods: The study comprised of 200 cases of staphylococcal pyodermas, derived from the community (150 cases and hospital (50 cases. Patients were evaluated based on their clinical presentation; antibiotic susceptibility was tested using the Kirby-Bauer disk diffusion method. Statistical Analysis Used: Statistical significance between individual attributes between the community and HA staphylococcal pyoderma groups was analyzed using Chi-square test and mean differences using student′s t-test. Results: Factors associated with community-associated (CA pyodermas were young age (P = 0.0021, primary pyodermas, and involvement of extremities, while those with HA pyodermas were middle age, secondary pyodermas, and significantly increased body surface involvement (P = 0.041. Incidence of CA-MRSA was 11.3%, while that of HA-MRSA was 18%. Conclusions: A high level of resistance to first-line drugs such as penicillin, ciprofloxacin and cotrimoxazole was observed, more so in the hospital strain than in the community strain. S. aureus demonstrated good susceptibility to cephalosporins. Though the two strains of MRSA differed clinically, they showed 100% sensitivity to vancomycin and linezolid.

  3. Isolation and Antibiotic Sensitivity of Bacillus thuringinesis Strain From Dump Soil

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    Sarker, D.

    2010-01-01

    Full Text Available Bacillus thuringiensis (or Bt is a commonly used as a pesticide. B. thuringiensis is a naturally-occurring soil bacterium, also occurs naturally in the gut of caterpillars of various types of moths and butterflies, as well as on the dark surface of plants. The xylanase producing bacterial strains were isolated from dump soil. The strains were isolated on xylan agar media and screening was carried out by xylanolysis method. To test the sensitivity of the isolates, ten different antibiotics were used. The strains were tested for resistance to doxycyclin, erythromycin, chloramphenical, cephallaxin, kanamycin, ampicillin, steptomycin, vancomycin, amoxycillin and neomycin. The strains showed sensitive to doxycyclin, erythromycin, chloramphenical, cephallaxin, kanamycin, ampicillin, steptomycin and vancomycin and also showed resistance to amoxycillin and neomycin, when tested by disc diffusion method on nutrient agar plate confirmed by antibiotic spread plate method. The inhibitory effect of B. thuringiensis strains against the test bacteria Bacillus subtilis, Sarcina lutca, Shigella dysenteriae, Shigella sonnei and Pseudomonus aeruginosa examined. It was found that, B. thuringiensis S1, B. thuringiensis S2 and B. thuringiensis S3 strains showed an inhibitory effect on all of the test bacteria.

  4. [Spanish Society of Pediatric Infectious Diseases, Spanish Society of Paediatric Clinical Immunology and Allergy, Spanish Association of Paediatric Primary Care, and the Spanish Society of Extra-hospital Paediatrics and Primary Health Care consensus document on antibiotic treatment in penicillin or amoxicillin allergy].

    Science.gov (United States)

    Baquero-Artigao, Fernando; Michavila, Antonio; Suárez-Rodriguez, Ángeles; Hernandez, Anselmo; Martínez-Campos, Leticia; Calvo, Cristina

    2017-02-01

    The suspected allergy to beta-lactam antibiotics, especially penicillin and amoxicillin, is the most frequent reason for consultation in Child Allergy Units. In this consensus document, the clinical and diagnostic criteria of allergic reactions are described, as well as alternative antibiotic treatment for the most common infections diagnosed in paediatrics for patients with known or suspected allergy. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Extended spectrum beta-lactamase-producing Escherichia coli forms filaments as an initial response to cefotaxime treatment

    DEFF Research Database (Denmark)

    Kjeldsen, Thea S. B.; Sommer, Morten Otto Alexander; Olsen, John E.

    2015-01-01

    Background: beta-lactams target the peptidoglycan layer in the bacterial cell wall and most beta-lactam antibiotics cause filamentation in susceptible Gram-negative bacteria at low concentrations. The objective was to determine the initial morphological response of cephalosporin resistant CTX-M-1......-producing E. coli to cefotaxime and to determine whether the response depended on the growth phase of the bacterium and the concentration of antibiotic. Results: Two antibiotic resistant strains carrying bla(CTX-M-1) on the chromosome and on an IncI1 plasmid and three sensitive strains were used...... to cefotaxime. The filament formation was restricted to early growth phases and the time the cells grew as filaments was antibiotic concentration dependent. This indicates that antibiotic resistant E. coli undergo the same morphological changes as sensitive bacteria in the presence of beta-lactam antibiotic...

  6. Gas Plasma Pre-treatment Increases Antibiotic Sensitivity and Persister Eradication in Methicillin-Resistant Staphylococcus aureus

    Science.gov (United States)

    Guo, Li; Xu, Ruobing; Zhao, Yiming; Liu, Dingxin; Liu, Zhijie; Wang, Xiaohua; Chen, Hailan; Kong, Michael G.

    2018-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of serious nosocomial infections, and recurrent MRSA infections primarily result from the survival of persister cells after antibiotic treatment. Gas plasma, a novel source of ROS (reactive oxygen species) and RNS (reactive nitrogen species) generation, not only inactivates pathogenic microbes but also restore the sensitivity of MRSA to antibiotics. This study further found that sublethal treatment of MRSA with both plasma and plasma-activated saline increased the antibiotic sensitivity and promoted the eradication of persister cells by tetracycline, gentamycin, clindamycin, chloramphenicol, ciprofloxacin, rifampicin, and vancomycin. The short-lived ROS and RNS generated by plasma played a primary role in the process and induced the increase of many species of ROS and RNS in MRSA cells. Thus, our data indicated that the plasma treatment could promote the effects of many different classes of antibiotics and act as an antibiotic sensitizer for the treatment of antibiotic-resistant bacteria involved in infectious diseases. PMID:29628915

  7. Environmental cycle of antibiotic resistance encoded genes: A systematic review

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    R. ghanbari

    2017-12-01

    Full Text Available Antibiotic-resistant bacteria and genes enter the environment in different ways. The release of these factors into the environment has increased concerns related to public health. The aim of the study was to evaluate the antibiotic resistance genes (ARGs in the environmental resources. In this systematic review, the data were extracted from valid sources of information including ScienceDirect, PubMed, Google Scholar and SID. Evaluation and selection of articles were conducted on the basis of the PRISMA checklist. A total of 39 articles were included in the study, which were chosen from a total of 1249 papers. The inclusion criterion was the identification of genes encoding antibiotic resistance against the eight important groups of antibiotics determined by using the PCR technique in the environmental sources including municipal and hospital wastewater treatment plants, animal and agricultural wastes, effluents from treatment plants, natural waters, sediments, and drinking waters. In this study, 113 genes encoding antibiotic resistance to eight groups of antibiotics (beta-lactams, aminoglycosides, tetracyclines, macrolides, sulfonamides, chloramphenicol, glycopeptides and quinolones were identified in various environments. Antibiotic resistance genes were found in all the investigated environments. The investigation of microorganisms carrying these genes shows that most of the bacteria especially gram-negative bacteria are effective in the acquisition and the dissemination of these pollutants in the environment. Discharging the raw wastewaters and effluents from wastewater treatments acts as major routes in the dissemination of ARGs into environment sources and can pose hazards to public health.

  8. Intraspecies comparative genomics of three strains of Orientia tsutsugamushi with different antibiotic sensitivity.

    Science.gov (United States)

    Liao, Hsiao-Mei; Chao, Chien-Chung; Lei, Haiyan; Li, Bingjie; Tsai, Shien; Hung, Guo-Chiuan; Ching, Wei-Mei; Lo, Shyh-Ching

    2017-06-01

    We recently reported the genome of Orientia tsutsugamushi (OT) strain Karp (GenBank Accession #: NZ_LYMA00000000.2, https://www.ncbi.nlm.nih.gov/nuccore/NZ_LYMA00000000.2) with > 2 Mb in size through clone-based sequencing and high throughput genomic shotgun sequencing (HTS). The genomes of OT strains AFSC4 and AFSC7 were similarly sequenced by HTS Since strains AFSC4 (GenBank Accession #: NZ_LYMT00000000.1, https://www.ncbi.nlm.nih.gov/nuccore/1035784408) and AFSC7 (GenBank Accession #: NZ_LYMB00000000.1, https://www.ncbi.nlm.nih.gov/nuccore/1035854767) were more resistant to antibiotics than strain Karp, we conducted comparative analysis of the three draft genomes annotated by RAST server aimed to identify possible genetic bases of difference in microbial antibiotic sensitivity. Intraspecies comparative genomics analysis of the three OT strains revealed that two ORFs encoding hypothetical proteins in both strains AFSC4 and AFSC7 are absent in strain Karp.

  9. Epidemiology of urinary tract infections and antibiotics sensitivity among pregnant women at Khartoum North Hospital

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    Ali Salah K

    2011-01-01

    Full Text Available Abstract Background Urinary tract infections (UTI can lead to poor maternal and perinatal outcomes. Investigating epidemiology of UTI and antibiotics sensitivity among pregnant women is fundamental for care-givers and health planners. Methods A cross sectional study has been conducted at Khartoum north teaching hospital Antenatal Care Clinic between February-June 2010, to investigate epidemiology of UTI and antibiotics resistance among pregnant women. Structured questionnaires were used to gather data from pregnant women. UTI was diagnosed using mid stream urine culture on standard culture media Results Out of 235 pregnant women included, 66 (28.0% were symptomatic and 169 (71.9% asymptomatic. the prevalence of bacteriuria among symptomatic and asymptomatic pregnant women were (12.1%, and (14.7% respectively, with no significant difference between the two groups (P = 0.596, and the overall prevalence of UTI was (14.0%. In multivariate analyses, age, gestational age, parity, and history of UTI in index pregnancy were not associated with bacteriuria. Escherichia coli (42.4% and S. aureus (39.3% were the commonest isolated bacteria. Four, 2, 2, 3, 4, 2 and 0 out of 14 E. coli isolates, showed resistance to amoxicillin, naladixic acid, nitrofurantoin, ciprofloxacin, co-trimoxazole, amoxicillin/clavulanate and norfloxacin, respectively Conclusion Escherichia coli were the most prevalent causative organisms and showing multi drug resistance pattern, asymptomatic bacteriuria is more prevalent than symptomatic among pregnant women. Urine culture for screening and diagnosis purpose for all pregnant is recommended.

  10. Epidemiology of urinary tract infections and antibiotics sensitivity among pregnant women at Khartoum North Hospital.

    Science.gov (United States)

    Hamdan, Hamdan Z; Ziad, Abdel Haliem M; Ali, Salah K; Adam, Ishag

    2011-01-18

    Urinary tract infections (UTI) can lead to poor maternal and perinatal outcomes. Investigating epidemiology of UTI and antibiotics sensitivity among pregnant women is fundamental for care-givers and health planners. A cross sectional study has been conducted at Khartoum north teaching hospital Antenatal Care Clinic between February-June 2010, to investigate epidemiology of UTI and antibiotics resistance among pregnant women. Structured questionnaires were used to gather data from pregnant women. UTI was diagnosed using mid stream urine culture on standard culture media Out of 235 pregnant women included, 66 (28.0%) were symptomatic and 169 (71.9%) asymptomatic. the prevalence of bacteriuria among symptomatic and asymptomatic pregnant women were (12.1%), and (14.7%) respectively, with no significant difference between the two groups (P = 0.596), and the overall prevalence of UTI was (14.0%). In multivariate analyses, age, gestational age, parity, and history of UTI in index pregnancy were not associated with bacteriuria. Escherichia coli (42.4%) and S. aureus (39.3%) were the commonest isolated bacteria. Four, 2, 2, 3, 4, 2 and 0 out of 14 E. coli isolates, showed resistance to amoxicillin, naladixic acid, nitrofurantoin, ciprofloxacin, co-trimoxazole, amoxicillin/clavulanate and norfloxacin, respectively. Escherichia coli were the most prevalent causative organisms and showing multi drug resistance pattern, asymptomatic bacteriuria is more prevalent than symptomatic among pregnant women. Urine culture for screening and diagnosis purpose for all pregnant is recommended.

  11. DEFINITION OF ETIOLOGICAL ANTIBIOTIC SENSITIVITY FACTORS IN PURULENT-INFLAMMATORY PROCESSES.

    Science.gov (United States)

    Dubovyk, O; Mishyna, М; Malanchuk, S; Kuzmenko, A; Kozlov, O

    2017-10-01

    The purpose of the study - assessment of purulent-inflammatory processes etiologic factors and determination of microbial agents' in forms of plankton and biofilms sensitivity to antibiotics. Clinical microbial strains isolated from patients with purulent-inflammatory processes were the subject of the study. The study material comprised of wound tissue, pus, bandage and suture, catheters and drainage devices. Sensitivity of isolates to antimicrobial preparations with various mechanism of activity on the microbial cells was studied with the help of micro-test system. Formation of biofilms was studied with the help of definition of bacteria strains ability to adhesion to the surface of polystyrene flatbeds. It was revealed that one of the leading factors of purulent-inflammatory process development is S.aureus, which disseminated in 36,5% of cases; E.coli disseminated in 17,3% of cases. Among the agents of purulent-inflammatory processes the specific gravity attributed to: Proteus spp. - 14,6%, S.рyogenes - 12,8%, P.aeruginosa - 6,9%, K.pneumoniae - 6,7%. It was revealed that all isolates formed dense biofilms. It was demonstrated that most isolates in plankton form were sensitive to Novapime, Cefepime, Gatifloxacin, Imipenem; sensitive strains were registered in a smaller quantity to Gentamicin, Clindamycin and Doxycycline. In terms of sensitivity of isolates in the form of biofilm to antibacterial preparations it was revealed that most isolates were polyresistant to them. Thus, the study of the sensitivity of allotted microbial strains to antimicrobial preparations demonstrated, that there were strains among cultures with multiple resistances which was the consequence of a wide and not always effective use of antimicrobial preparations.

  12. Fluoromycobacteriophages for Rapid, Specific, and Sensitive Antibiotic Susceptibility Testing of Mycobacterium tuberculosis

    Science.gov (United States)

    Piuri, Mariana; Jacobs, William R.; Hatfull, Graham F.

    2009-01-01

    Rapid antibiotic susceptibility testing of Mycobacterium tuberculosis is of paramount importance as multiple- and extensively- drug resistant strains of M. tuberculosis emerge and spread. We describe here a virus-based assay in which fluoromycobacteriophages are used to deliver a GFP or ZsYellow fluorescent marker gene to M. tuberculosis, which can then be monitored by fluorescent detection approaches including fluorescent microscopy and flow cytometry. Pre-clinical evaluations show that addition of either Rifampicin or Streptomycin at the time of phage addition obliterates fluorescence in susceptible cells but not in isogenic resistant bacteria enabling drug sensitivity determination in less than 24 hours. Detection requires no substrate addition, fewer than 100 cells can be identified, and resistant bacteria can be detected within mixed populations. Fluorescence withstands fixation by paraformaldehyde providing enhanced biosafety for testing MDR-TB and XDR-TB infections. PMID:19300517

  13. Antibiotic sensitivity of escherichia coli isolated from urinary tract infection referred to Kermanshah central laboratory

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    Parviz Mohajeri

    2011-03-01

    Full Text Available Background: Escherichia coli (Ecoli has been considered as the most common agent of urinary tract infection in all regions. Recently, increased drug resistance has been lead to some problems in treatment related diseases. So, evaluation of resistance patterns of bacteria in each region could be a valuable guide for empirical treatment.Methods: All referred urine sample to Kermanshah Central Laboratory during 1998 that was reported positive to Ecoli were assessed. Susceptibility pattern to 19 antimicrobial agents was evaluated using Kirby Bauer method according to CLSI standards.Results: A total of 834 Ecoli isolated from 19,208 positive urine cultures. 84% of subjects were females and 16% males. Sensitivity rate for nitrofurantoin (84%, ceftizoxime (72%, norfloxacin (70%, cefotaxime (69%, Amikacin (66%, ciprofloxacin (65%, ceftriaxone (64%, ceftazidim (55% was higher than 50%. Sensitivity to nalidixic acid, cefexime, gentamicin, co-trimoxazole, ticarcillin, caphalexin, cephalotin, tetracycline, amoxicillin, amoxicillin clavulanate and ampicillin were determined less than 50%.Conclusion: Nitrofurantoin and ceftizoxime are currently effective against Ecoli, although an indiscriminate use of antibiotics should be avoided because of drug resistance probable. It seems that ampicillin could be excluded from routine sensitivity testing.

  14. Occurrence of Clostridium perfringens contamination in poultry feed ingredients: Isolation, identification and its antibiotic sensitivity pattern

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    Shanmugasundaram Udhayavel

    2017-09-01

    Full Text Available This work has been undertaken to study the occurrence of Clostridium perfringens contamination in the poultry feed ingredients and find out its in-vitro antibiotic sensitivity pattern to various antimicrobial drugs. Two hundred and ninety-eight poultry feed ingredient samples received at Poultry Disease Diagnosis and Surveillance Laboratory, Namakkal, Tamil Nadu in South India were screened for the presence of C. perfringens. The organisms were isolated in Perfringens agar under anaerobic condition and subjected to standard biochemical tests for confirmation. In vitro antibiogram assay has been carried out to determine the sensitivity pattern of the isolates to various antimicrobial drugs. One hundred and one isolates of C. perfringens were obtained from a total of 298 poultry feed ingredient samples. Overall positivity of 33.89% could be made from the poultry feed ingredients. Highest level of C. perfringens contamination was detected in fish meal followed by bone meal, meat and bone meal and dry fish. Antibiogram assay indicated that the organisms are highly sensitive to gentamicin (100%, chlortetracycline (96.67%, gatifloxacin (93.33%, ciprofloxacin (86.67%, ofloxacin (86.67% and lincomycin (86.67%. All the isolates were resistant to penicillin-G. Feed ingredients rich in animal proteins are the major source of C. perfringens contamination.

  15. Blood culture gram stain, acridine orange stain and direct sensitivity-based antimicrobial therapy of bloodstream infection in patients with trauma.

    Science.gov (United States)

    Behera, B; Mathur, P; Gupta, B

    2010-01-01

    The purpose of this study was to ascertain if the simple practice of Gram stain, acridine orange stain and direct sensitivity determination of positive blood culture bottles could be used to guide early and appropriate treatment in trauma patients with clinical suspicion of sepsis. The study also aimed to evaluate the error in interpreting antimicrobial sensitivity by direct method when compared to standard method and find out if specific antibiotic-organism combination had more discrepancies. Findings from consecutive episodes of blood stream infection at an Apex Trauma centre over a 12-month period are summarized. A total of 509 consecutive positive blood cultures were subjected to Gram staining. AO staining was done in BacT/ALERT-positive Gram-stain negative blood cultures. Direct sensitivity was performed from 369 blood culture broths, showing single type of growth in Gram and acridine orange staining. Results of direct sensitivity were compared to conventional sensitivity for errors. No 'very major' discrepancy was found in this study. About 5.2 and 1.8% minor error rates were noted in gram-positive and gram-negative bacteria, respectively, while comparing the two methods. Most of the discrepancies in gram-negative bacteria were noted in beta lactam - beta lactamase inhibitor combinations. Direct sensitivity testing was not reliable for reporting of methicillin and vancomycin resistance in Staphylococci. Gram stain result together with direct sensitivity testing is required for optimizing initial antimicrobial therapy in trauma patients with clinical suspicion of sepsis. Gram staining and AO staining proved particularly helpful in the early detection of candidaemia.

  16. Reversing Bacterial Resistance to Antibiotics by Phage-Mediated Delivery of Dominant Sensitive Genes

    OpenAIRE

    Edgar, Rotem; Friedman, Nir; Molshanski-Mor, Shahar; Qimron, Udi

    2012-01-01

    Pathogen resistance to antibiotics is a rapidly growing problem, leading to an urgent need for novel antimicrobial agents. Unfortunately, development of new antibiotics faces numerous obstacles, and a method that resensitizes pathogens to approved antibiotics therefore holds key advantages. We present a proof of principle for a system that restores antibiotic efficiency by reversing pathogen resistance. This system uses temperate phages to introduce, by lysogenization, the genes rpsL and gyrA...

  17. Antibacterial effect of mango (Mangifera indica Linn.) leaf extract against antibiotic sensitive and multi-drug resistant Salmonella typhi.

    Science.gov (United States)

    Hannan, Abdul; Asghar, Samra; Naeem, Tahir; Ikram Ullah, Muhammad; Ahmed, Ijaz; Aneela, Syeda; Hussain, Shabbir

    2013-07-01

    Alternative herbal medicine has been used to treat various infections from centuries. Natural plants contain phytoconstituents having similar chemical properties as of synthetic antibiotics. Typhoid fever is a serious infection and failure of its treatment emerged multi-drug resistant (MDR) bugs of Salmonella typhi. Due to multiple and repeated issues with antibiotics efficacy, it became essential to evaluate biological properties of plants from different geographical origins. Mango leaves have been Reported for various medicinal effects like antioxidant, antimicrobial, antihelminthic, antidiabetic and antiallergic etc. Objective of present study was to investigate anti-typhoid properties of acetone mango leaf extract (AMLE) against antibiotic sensitive and MDR S. typhi isolates. A total of 50 isolates of S. typhi including MDR (n=30) and antibiotic sensitive (n=20) were investigated. Staphylococcus aureus (ATCC 25923) and Salmonella typhimurium (ATCC14028) were used as quality control strains. AMLE was prepared and its antibacterial activity was evaluated by agar well diffusion screening method and minimum inhibitory concentration (MIC), by agar dilution technique. Zone of inhibition (mm) of AMLE against MDR and antibiotic sensitive isolates was 18±1.5mm (Mean±S.D). Zone of S. aureus (ATCC 25923) and S. typhimurium (ATCC14028) was 20±1.5mm (Mean±S.D). MIC of AMLE was Reported in range from 10-50 mg/ml. The present study described the inhibitory effects of mango leaves against S. typhi.

  18. Longitudinal nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in indigenous Australian and Alaska native children with bronchiectasis.

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    Kim M Hare

    Full Text Available BACKGROUND: Indigenous children in Australia and Alaska have very high rates of chronic suppurative lung disease (CSLD/bronchiectasis. Antibiotics, including frequent or long-term azithromycin in Australia and short-term beta-lactam therapy in both countries, are often prescribed to treat these patients. In the Bronchiectasis Observational Study we examined over several years the nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in these two PCV7-vaccinated populations. METHODS: Indigenous children aged 0.5-8.9 years with CSLD/bronchiectasis from remote Australia (n = 79 and Alaska (n = 41 were enrolled in a prospective cohort study during 2004-8. At scheduled study visits until 2010 antibiotic use in the preceding 2-weeks was recorded and nasopharyngeal swabs collected for culture and antimicrobial susceptibility testing. Analysis of respiratory bacterial carriage and antibiotic resistance was by baseline and final swabs, and total swabs by year. RESULTS: Streptococcus pneumoniae carriage changed little over time. In contrast, carriage of Haemophilus influenzae declined and Staphylococcus aureus increased (from 0% in 2005-6 to 23% in 2010 in Alaskan children; these changes were associated with increasing age. Moraxella catarrhalis carriage declined significantly in Australian, but not Alaskan, children (from 64% in 2004-6 to 11% in 2010. While beta-lactam antibiotic use was similar in the two cohorts, Australian children received more azithromycin. Macrolide resistance was significantly higher in Australian compared to Alaskan children, while H. influenzae beta-lactam resistance was higher in Alaskan children. Azithromycin use coincided significantly with reduced carriage of S. pneumoniae, H. influenzae and M. catarrhalis, but increased carriage of S. aureus and macrolide-resistant strains of S. pneumoniae and S. aureus (proportion of carriers and all swabs, in a 'cumulative dose-response' relationship

  19. Distinct fermentation and antibiotic sensitivity profiles exist in salmonellae of canine and human origin.

    Science.gov (United States)

    Wallis, Corrin V; Lowden, Preena; Marshall-Jones, Zoe V; Hilton, Anthony C

    2018-02-26

    Salmonella enterica is a recognised cause of diarrhoea in dogs and humans, yet the potential for transfer of salmonellosis between dogs and their owners is unclear, with reported evidence both for and against Salmonella as a zoonotic pathogen. A collection of 174 S. enterica isolates from clinical infections in humans and dogs were analysed for serotype distribution, carbon source utilisation, chemical and antimicrobial sensitivity profiles. The aim of the study was to understand the degree of conservation in phenotypic characteristics of isolates across host species. Serovar distribution across human and canine isolates demonstrated nine serovars common to both host species, 24 serovars present in only the canine collection and 39 solely represented within the human collection. Significant differences in carbon source utilisation profiles and ampicillin, amoxicillin and chloramphenicol sensitivity profiles were detected in isolates of human and canine origin. Differences between the human and canine Salmonella collections were suggestive of evolutionary separation, with canine isolates better able to utilise several simple sugars than their human counterparts. Generally higher minimum inhibitory concentrations of three broad-spectrum antimicrobials, commonly used in veterinary medicine, were also observed in canine S. enterica isolates. Differential carbon source utilisation and antimicrobial sensitivity profiles in pathogenic Salmonella isolated from humans and dogs are suggestive of distinct reservoirs of infection for these hosts. Although these findings do not preclude zoonotic or anthroponotic potential in salmonellae, the separation of carbon utilisation and antibiotic profiles with isolate source is indicative that infectious isolates are not part of a common reservoir shared frequently between these host species.

  20. Clinical profile and antibiotics sensitivity in childhood urinary tract infection at Dhulikhel Hospital.

    Science.gov (United States)

    Singh, S D; Madhup, S K

    2013-01-01

    Urinary Tract Infection implies presence of actively multiplying organisms in the urinary tract. Although it is infrequently associated with mortality, it is still a significant cause of morbidity. Early diagnosis is critical to preserve renal function of growing kidney. Our purpose was to determine the clinical, microbiologic profile and antibiotic sensitivity of such infections in pediatric Urinary Tract Infection (UTI) patients at Dhulikhel Hospital. A hospital based prospective descriptive study of 135 children from 2 months to 16 years, with clinical diagnosis of urinary tract infection who visited the pediatric department of Dhulikhel Hospital over the period of 15 months were enrolled in the study. All patients underwent routine urine analysis and culture. Children with recurrent UTI underwent micturating cystourethrogram (MCUG). Children with recurrent UTI of more than two years and with feature of pyelonephritis underwent USG abdomen as well. Complications and response of the treatment was observed in all cases of UTI. All data were entered in Epidata and data analysis was done using spss 16 version. Among 135 children, 32.5% were male and 67.4% were female. Fever was the most common presenting symptom in 74.80% of patients followed by dysuria in 54.1%. Among these children 95.6% had significant pyuria and 45% had culture positive infection. Children who showed positive for bacteriuria, Escherichia coli (78.7%) was the most common organism and are more than 80% sensitive to Amikacin, Gentamicin, Ceftriaxone, Ofloxacin, Nalidixic acid, Imipenem and Vancomycin. Co-trimoxazole was the most common drug used for treatment with a mean drug respond time of (mean+/-S.D) of 2.21+/-.78 days. 2+/-. Children who had recurrent UTI were more prone to develop culture positive UTI (p=0.0001). Urinary Tract Infection in female was almost twice more common than in male. Cotrimoxazole was the most common drug used for treatment, sensitivity of this drug was less than 50% for

  1. Integrating human and environmental health in antibiotic risk assessment: A critical analysis of protection goals, species sensitivity and antimicrobial resistance.

    Science.gov (United States)

    Le Page, Gareth; Gunnarsson, Lina; Snape, Jason; Tyler, Charles R

    2017-12-01

    Antibiotics are vital in the treatment of bacterial infectious diseases but when released into the environment they may impact non-target organisms that perform vital ecosystem services and enhance antimicrobial resistance development with significant consequences for human health. We evaluate whether the current environmental risk assessment regulatory guidance is protective of antibiotic impacts on the environment, protective of antimicrobial resistance, and propose science-based protection goals for antibiotic manufacturing discharges. A review and meta-analysis was conducted of aquatic ecotoxicity data for antibiotics and for minimum selective concentration data derived from clinically relevant bacteria. Relative species sensitivity was investigated applying general linear models, and predicted no effect concentrations were generated for toxicity to aquatic organisms and compared with predicted no effect concentrations for resistance development. Prokaryotes were most sensitive to antibiotics but the range of sensitivities spanned up to several orders of magnitude. We show reliance on one species of (cyano)bacteria and the 'activated sludge respiration inhibition test' is not sufficient to set protection levels for the environment. Individually, neither traditional aquatic predicted no effect concentrations nor predicted no effect concentrations suggested to safeguard for antimicrobial resistance, protect against environmental or human health effects (via antimicrobial resistance development). Including data from clinically relevant bacteria and also more species of environmentally relevant bacteria in the regulatory framework would help in defining safe discharge concentrations for antibiotics for patient use and manufacturing that would protect environmental and human health. It would also support ending unnecessary testing on metazoan species. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Significant Differences Characterise the Correlation Coefficients between Biocide and Antibiotic Susceptibility Profiles in Staphylococcus aureus.

    Science.gov (United States)

    Oggioni, Marco R; Coelho, Joana Rosado; Furi, Leonardo; Knight, Daniel R; Viti, Carlo; Orefici, Graziella; Martinez, Jose-Luis; Freitas, Ana Teresa; Coque, Teresa M; Morrissey, Ian

    2015-01-01

    There is a growing concern by regulatory authorities for the selection of antibiotic resistance caused by the use of biocidal products. We aimed to complete the detailed information on large surveys by investigating the relationship between biocide and antibiotic susceptibility profiles of a large number of Staphylococcus aureus isolates using four biocides and antibiotics commonly used in clinical practice. The minimal inhibitory concentration (MIC) for most clinically-relevant antibiotics was determined according to the standardized methodology for over 1600 clinical S. aureus isolates and compared to susceptibility profiles of benzalkonium chloride, chlorhexidine, triclosan, and sodium hypochlorite. The relationship between antibiotic and biocide susceptibility profiles was evaluated using non-linear correlations. The main outcome evidenced was an absence of any strong or moderate statistically significant correlation when susceptibilities of either triclosan or sodium hypochlorite were compared for any of the tested antibiotics. On the other hand, correlation coefficients for MICs of benzalkonium chloride and chlorhexidine were calculated above 0.4 for susceptibility to quinolones, beta-lactams, and also macrolides. Our data do not support any selective pressure for association between biocides and antibiotics resistance and furthermore do not allow for a defined risk evaluation for some of the compounds. Importantly, our data clearly indicate that there does not involve any risk of selection for antibiotic resistance for the compounds triclosan and sodium hypochlorite. These data hence infer that biocide selection for antibiotic resistance has had so far a less significant impact than feared.

  3. Flomoxef, a new oxacephem antibiotic, does not cause hemostatic defects.

    Science.gov (United States)

    Cazzola, M; Brancaccio, V; De Giglio, C; Paternò, E; Matera, M G; Rossi, F

    1993-03-01

    Antibiotics of the beta-lactam class may cause coagulation defects and bleeding. It has been suggested that N-methyltetrazolethiol (NMTT), a common side chain group at the 3'-position of the cephem or 1-oxacephem frame, could be responsible for the hypoprothrombinemic effect of the antibiotics and that it could inhibit the liver vitamin K-epoxide reductase activity. Flomoxef (6315-S) is a new oxacephem antibiotic which differs from latamoxef because it has [1-(2-hydroxethyl)-1H-tetrazol-5-yl] thiomethyl (HTT) as a side chain at the 3'-position of cephem group instead of NMTT and an extensive modification of 7 beta-acylamino side chain. The present study was carried out to study its effects on vitamin K-dependent blood coagulation parameters in human volunteers. Ten adult patients (6 men and 4 women), suffering from chronic bronchitis, entered into the study. Each patient received ten 1 g i.m. injections of flomoxef at 12-hourly intervals. Apparently, the treatment with this oxacephem antibiotic had no significant effect. PT, PTT and fibrinogen remained in the normal range in all patients and factors II+VII+X, protein C, protein S and AT III were not depleted. The trend was similar both in men and women. Based on the results of the present study, we conclude that flomoxef is an antibiotic that does not exhibit an effect on blood coagulation, even in males.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. The Role of Antibiotics in Modulating Virulence in Staphylococcus aureus.

    Science.gov (United States)

    Hodille, Elisabeth; Rose, Warren; Diep, Binh An; Goutelle, Sylvain; Lina, Gerard; Dumitrescu, Oana

    2017-10-01

    Staphylococcus aureus is often involved in severe infections, in which the effects of bacterial virulence factors have great importance. Antistaphylococcal regimens should take into account the different effects of antibacterial agents on the expression of virulence factors and on the host's immune response. A PubMed literature search was performed to select relevant articles on the effects of antibiotics on staphylococcal toxin production and on the host immune response. Information was sorted according to the methods used for data acquisition (bacterial strains, growth models, and antibiotic concentrations) and the assays used for readout generation. The reported mechanisms underlying S. aureus virulence modulation by antibiotics were reviewed. The relevance of in vitro observations is discussed in relation to animal model data and to clinical evidence extracted from case reports and recommendations on the management of toxin-related staphylococcal diseases. Most in vitro data point to a decreased level of virulence expression upon treatment with ribosomally active antibiotics (linezolid and clindamycin), while cell wall-active antibiotics (beta-lactams) mainly increase exotoxin production. In vivo studies confirmed the suppressive effect of clindamycin and linezolid on virulence expression, supporting their utilization as a valuable management strategy to improve patient outcomes in cases of toxin-associated staphylococcal disease. Copyright © 2017 American Society for Microbiology.

  5. The Most Prevalnet Organism in Diabetic Foot Ulcers and Its Drug Sensitivity and Resistance to Different Standard Antibiotics

    International Nuclear Information System (INIS)

    Nageen, A.

    2016-01-01

    Objective: To find the most prevalent organism in diabetic foot ulcers and its drug sensitivity and resistance to different standard antibiotics. Study Design: Adescriptive and cross-sectional study. Place and Duration of Study: Ward 7, Jinnah Postgraduate Medical Center, Karachi, from December 2010 to December 2012. Methodology: Ninety-five diabetic patients with infected foot wounds of Wegener grade 2 - 5 who had not received any previous antibiotics were included in the study by consecutive sampling. Pus culture specimen from wounds was taken and the organism isolated was identified. Also the most sensitive group of antibiotics and the most resistant one to that organism was noted. Results: Staphylococcus aureus was the most prevalent organism constituting 23.16% (n=22) of the organisms isolated; Escherichia coli with 17.89% (n=17) and Klebsiella with 12.63% (n=12) followed. Males presented more with diabetic foot (n=52) out of 95 patients. The most common age group affected was 41 - 60 years (73 patients). The organisms were most sensitive to Meropenem, effective in 90 (95%) patients and most resistant to Cotrimoxazole (80, 84% patients). Out of the 95 patients, 39 (41%) patients were hypertensive, 30 (31.5%) were obese and 14 (15%) were smokers. Staphylococcus aureus was the most prevalent organism overall irrespective to gender, age groups and co-morbidity of the patients. Conclusion: Staphylococcus aureus was the most frequent organism in diabetic foot ulcers; the most effective antibiotic is Meropenem and least effective is Cotrimoxazole. (author)

  6. [Profile and susceptibility to antibiotics in urinary tract infections in children and newborns from 2012 to 2013: Data from 1879 urine cultures].

    Science.gov (United States)

    Marzouk, M; Ferjani, A; Haj Ali, M; Boukadida, J

    2015-05-01

    We present recent data on the bacteriological profile and antibiotic susceptibility of uropathogenic bacteria isolated in children and newborns in our region over the past 2 years. A retrospective study on the positive urine cultures from pediatric and neonatal populations during 2012-2013. Bacteria were identified using conventional methods. Susceptibility testing was performed and interpreted as recommended by the committee of the susceptibility of the French Society of Microbiology (CA-SFM). We collected 1879 non-redundant bacteria with more than 73% Escherichia coli. Children and infants (mean age, 32 months [range, 1 month to 14 years]) accounted for 84% of the bacteria collected and newborns (mean age, 12 days [range, 1 day to 1 month]) 16%. A female predominance was observed in the pediatric population (M:F sex ratio, 3.2), whereas for the neonatal population, the proportions were almost identical in both sexes (M:F sex ratio, 1.1). Most of the positive urine cultures (n=1234) were from the community. Hospitalized patients (n=636) were divided into pediatric (60%) and neonatal units (40%). Five bacterial genera dominated the bacteriological profile: E. coli, Klebsiella sp., Proteus sp., Enterobacter sp., and Enterococcus. The susceptibility of the main BUP antibiotics used for treatment of frequent UTI showed the effectiveness of furadoine, imipenem, fosfomycin, and colistin. Amoxicillin kept constant activity against Enterococcus and Streptococcus agalactiae. The rates of resistance of Enterobacteriaceae to beta-lactam antibiotics were high, especially in the neonatal population. The production of extended-spectrum beta-lactamase (ESBL) was noted in 12.8% of pediatric Enterobacteria vs. 22.6% of the neonatal strains. For community Enterobacteriaceae, the activity of beta-lactam antibiotics was limited with 11.2% resistance to third-generation cephalosporins (C3G), including 8.6% ESBL production. The impact of widespread use of beta-lactam antibiotics in

  7. The Sensitization of Legionella pneumophila to Some Antibiotics by Reserpine and Anti-Legionella Effects of Different Benzofuranone Derivatives

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    Mohsen Khaleghi

    2015-10-01

    Full Text Available Background: Legionella pneumophila is  a  dangerous pathogenic bacterium can cause serious infectious diseases especially in hospitalized immuno-compromised patients. This bacterium is shown to be resistant against different antibiotics. Resistance against a wide range of antibiotics is usually mediated by efflux pump in bacteria. Efflux pumps are proteinaceous transporters localized in the cytoplasmic membrane of all kinds of cells which excreted antibiotics outside the cells. However, synthesis of new anti-Legionella compounds or selection of resistant modulating agents are useful strategy to combat with L. pneumophilain the future.Methods: In this study the antibacterial activity of some benzofuranone derivatives have been investigated by disk diffusion method against L. pneumophila. Also the sensitivity of this test strain was evaluated against 19 antibiotics and the combination effect of reserpine at a sub-inhibitory concentration was further studied with these antibiotics using disk diffusion method with some modifications.Conclusion: Among the different synthetic compounds which were tested against L. pneumophila, the most antibacterial activity was observed for compounds 1j and 1m which contain hydroxyl and methoxy groups on the C-6 and C-7 positionsagainst L. pneumophila. To evaluate whether efflux pumps are active in L. pneumophila or not an efflux inhibitor (reserpine was tested in combination of different antibiotics against this test strain. Reserpine significantly enhanced the antibacterial activities of kanamycin, nitrofurantoin, co-trimoxazole, erythromycin, ofloxacillin, gentamycin, rifampin, ciprofloxacin, nalidixic acid, minocycline, tobramycin, and amikacin against L. pneumophila which shows the resistances to these antibiotics are mediated by efflux system in this bacterium.

  8. Antibiotic resistant pattern of methicillin resistant and sensitive Staphylococcus aureus isolated from patients durining 2009-2010, Ahvaz, Iran.

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    N Parhizgari

    2013-12-01

    Full Text Available Abstract Background & aim: Staphylococcus aureus is one of the most important nosocomial infecting agents resistant to commonly used antibiotics. Nowadays, methicillin-resistant S. aureus (MRSA is considered one of the main causes of nosocomial infections. The aim of this study was to identify the antibiotic resistance pattern of methicicllin- resistant and susceptible strains in Ahwaz, Iran. Methods: In the present cross - sectional study, a number of 255 clinically suspected cases of Staphylococcus aureus were collected during a 19 month period. The bacteria were investigated using standard biochemical tests such as catalase, mannitol fermentation, coagulase and Dnase. Sensitive strains were confirmed by disk diffusion method compared to commonly used antibiotics. The collected data were analyzed using descriptive statistical tests. Results: of 255 suspected cases, 180 were confirmed as S.aureus, a total of 59 strains of S. aureus (2/37 percent were resistant to methicillin. Resistance to S. aureus strains resistant to methicillin included: chloramphenicol (3.38%, rifampin (45.76%, norfloxacin (89.83%, gentamicin (89.83%, ciprofloxacin, (91.52%, azithromycin, (88.13%, cotrimoxazole (86.44% and all isolates strains were sensitive to vancomycin and nitrofurantoin. A total of 10 different patterns of antibiotic resistance in methicillin-resistant Staphylococcus aureus strains were identified. Conclusion: Expression of new resistance factor in nosocomial infection is one of the major challenges in treating these infections. This study showed a high prevalence of resistance against some class of antibiotics in MRSA isolated from Imam Khomeini and Golestan hospital of Ahwaz, Iran. Key words: Nosocomial infection, Methicillin Resistant Staphylococcus aureus (MRSA, Antibiotic Resistant Pattern

  9. Isolation, identification, characterization and antibiotic sensitivity profile of pathogenic Legionella pneumophila isolates from different water sources

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    Kannan Subbaram

    2017-05-01

    Conclusions: Serious and fatal L. pneumophila infections may be transmitted through water. Legionella can survive under various conditions in various water sources. L. pneumophila is the important pathogen causing human disease. Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics.

  10. Comparing the sensitivity of algal, cyanobacterial and bacterial bioassays to different groups of antibiotics

    NARCIS (Netherlands)

    van der Grinten, E.; Pikkemaat, M.G.; van den Brandhof, E.J.; Stroomberg, G.J.; Kraak, M.H.S.

    2010-01-01

    Antibiotics may affect both primary producers and decomposers, potentially disrupting ecosystem processes. Hence, it is essential to assess the impact of antibiotics on aquatic ecosystems. The aim of the present study was therefore to evaluate the potential of a recently developed test for detecting

  11. Functional Repertoire of Antibiotic Resistance Genes in Antibiotic Manufacturing Effluents and Receiving Freshwater Sediments

    Science.gov (United States)

    González-Plaza, Juan J.; Šimatović, Ana; Milaković, Milena; Bielen, Ana; Wichmann, Fabienne; Udiković-Kolić, Nikolina

    2018-01-01

    Environments polluted by direct discharges of effluents from antibiotic manufacturing are important reservoirs for antibiotic resistance genes (ARGs), which could potentially be transferred to human pathogens. However, our knowledge about the identity and diversity of ARGs in such polluted environments remains limited. We applied functional metagenomics to explore the resistome of two Croatian antibiotic manufacturing effluents and sediments collected upstream of and at the effluent discharge sites. Metagenomic libraries built from an azithromycin-production site were screened for resistance to macrolide antibiotics, whereas the libraries from a site producing veterinary antibiotics were screened for resistance to sulfonamides, tetracyclines, trimethoprim, and beta-lactams. Functional analysis of eight libraries identified a total of 82 unique, often clinically relevant ARGs, which were frequently found in clusters and flanked by mobile genetic elements. The majority of macrolide resistance genes identified from matrices exposed to high levels of macrolides were similar to known genes encoding ribosomal protection proteins, macrolide phosphotransferases, and transporters. Potentially novel macrolide resistance genes included one most similar to a 23S rRNA methyltransferase from Clostridium and another, derived from upstream unpolluted sediment, to a GTPase HflX from Emergencia. In libraries deriving from sediments exposed to lower levels of veterinary antibiotics, we found 8 potentially novel ARGs, including dihydrofolate reductases and beta-lactamases from classes A, B, and D. In addition, we detected 7 potentially novel ARGs in upstream sediment, including thymidylate synthases, dihydrofolate reductases, and class D beta-lactamase. Taken together, in addition to finding known gene types, we report the discovery of novel and diverse ARGs in antibiotic-polluted industrial effluents and sediments, providing a qualitative basis for monitoring the dispersal of ARGs

  12. Functional Repertoire of Antibiotic Resistance Genes in Antibiotic Manufacturing Effluents and Receiving Freshwater Sediments

    Directory of Open Access Journals (Sweden)

    Juan J. González-Plaza

    2018-01-01

    Full Text Available Environments polluted by direct discharges of effluents from antibiotic manufacturing are important reservoirs for antibiotic resistance genes (ARGs, which could potentially be transferred to human pathogens. However, our knowledge about the identity and diversity of ARGs in such polluted environments remains limited. We applied functional metagenomics to explore the resistome of two Croatian antibiotic manufacturing effluents and sediments collected upstream of and at the effluent discharge sites. Metagenomic libraries built from an azithromycin-production site were screened for resistance to macrolide antibiotics, whereas the libraries from a site producing veterinary antibiotics were screened for resistance to sulfonamides, tetracyclines, trimethoprim, and beta-lactams. Functional analysis of eight libraries identified a total of 82 unique, often clinically relevant ARGs, which were frequently found in clusters and flanked by mobile genetic elements. The majority of macrolide resistance genes identified from matrices exposed to high levels of macrolides were similar to known genes encoding ribosomal protection proteins, macrolide phosphotransferases, and transporters. Potentially novel macrolide resistance genes included one most similar to a 23S rRNA methyltransferase from Clostridium and another, derived from upstream unpolluted sediment, to a GTPase HflX from Emergencia. In libraries deriving from sediments exposed to lower levels of veterinary antibiotics, we found 8 potentially novel ARGs, including dihydrofolate reductases and beta-lactamases from classes A, B, and D. In addition, we detected 7 potentially novel ARGs in upstream sediment, including thymidylate synthases, dihydrofolate reductases, and class D beta-lactamase. Taken together, in addition to finding known gene types, we report the discovery of novel and diverse ARGs in antibiotic-polluted industrial effluents and sediments, providing a qualitative basis for monitoring the

  13. Extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae: critical tools for antibiotic resistance pattern.

    Science.gov (United States)

    Padmini, Nagarajan; Ajilda, Antony Alex Kennedy; Sivakumar, Natesan; Selvakumar, Gopal

    2017-06-01

    Drug resistance is a phenomenon where by an organism becomes fully or partially resistant to drugs or antibiotics being used against it. Antibiotic resistance poses an exacting intimidation for people with underlying medical immune conditions or weakened immune systems. Infections caused by the enzyme extended spectrum β-lactamase (ESBL) producing multi drug resistance (MDR) Enterobacteriaceae especially Escherichia coli and Klebsiella pneumoniae are resistant to a broad range of beta lactams, including third generation cephalosporins. Among all the pathogens, these two MDR E. coli and K. pneumoniae have emerged as one of the world's greatest health threats in past two decades. The nosocomial infections caused by these ESBL producing MDR E. coli and K. pneumoniae complicated the therapy and limit treatment options. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Antibiotic sensitivity pattern of Staphylococcus aureus from clinical isolates in a tertiary health institution in Kano, Northwestern Nigeria

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    Nwankwo Emmanuel Onwubiko

    2011-01-01

    Full Text Available BACKGROUND: The importance of Staphylococcus aureus as a persistent nosocomial and community acquired pathogen has become a global health concern. It has a remarkable capability of evolving different mechanisms of resistance to most antimicrobial agents. The aim of the present study is to establish the incidence of S. aureus in clinical specimens and its antibiotic sensitivity pattern to various antibiotics in this locality. METHODS: One hundred and fifty consecutive isolates of S. aureus obtained from various clinical specimens between January and December 2009 sent to the Medical Microbiology Laboratory Department of Aminu Kano Teaching Hospital (AKTH were confirmed by standard bacteriological procedures. Antibiotic sensitivity pattern was carried out by disc diffusion method. RESULTS: The age group with the highest number of isolates was (0-10yrs while wound infection had the highest frequency of S. aureus isolates (30.7% in the study. Males (62.0% were more infected than females (38.0%. The sensitivity pattern of S. aureus to the following antibiotics; Gentamicin, Amoxycillin/clavulanate, Streptomycin, Cloxacillin, Erythromycin, Chloramphenicol, Cotrimoxazole, Tetracycline, Penicillin, Ciprofloxacin, Ofloxacin, Levofloxacin, Ceftriaxone, Amoxycillin and vancomycin were 92.4%, 63.0%, 44.2%, 35.8%, 52.4%, 61.9%, 15.5%, 31.2%, 7.1%, 78.9%, 76.6%, 100%, 71.4%, 30.7% and 100% respectively. Methicillin resistant isolates were sensitive to Levofloxacin 93.7% and Ofloxacin 68.7%. CONCLUSION: The results of the present study show that the fluoroquinolones are effective in the management of Staphylococcus aureus infections including methicillin resistant strains in this environment.

  15. BACTERIOLOGICAL PROFILE AND ANTIBIOTIC SENSITIVITY PATTERN IN ACUTE EXACERBATION OF ADVANCED CASES OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD

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    Avik

    2016-01-01

    Full Text Available Acute exacerbations are significant and frequent events in the natural history of chronic obstructive pulmonary disease. Majority of these exacerbations are of infectious aetiology, bacteria being responsible for 30-50% of these cases. With not many studies of similar type being conducted in the Indian context, this study was undertaken with the purpose of determining the bacteriology of acute exacerbations of chronic obstructive pulmonary disease in hospitalized patients with advanced disease and their antibiotic susceptibility pattern to formulate a cost effective algorithm for antibiotic usage while at the same time reducing the chances of emergence of drug resistance. Sputum sample from a total of 338 patients were send for Gram’s stain and culture sensitivity testing using an array of the commonly used antibiotics. Pathogenic bacteria were isolated from 203 (60.1% samples. Gram negative bacteria were isolated from 79.8 percent (162/203 cases while the rest were Gram positive. Klebsiella species were the commonest (49.2%; 100/203 Gram negative isolates from the sputum samples. Among the gram negative organisms, Carbapenem had the highest sensitivity (90.2% followed by Amikacin, Ciprofloxacin and Piperacillin-Tazobactam. Linezolid was found to be 100 percent sensitive amongst the Gram positive organisms while both Amoxicillin Clavulanate and Azithromycin showed a rather low sensitivity profile overall. 5.0 percent of the Klebsiella infections were multi drug resistant. It was thereby concluded that either Amikacin, Ciprofloxacin or Piperacillin-Tazobactam for be considered for Gram negative organisms and Linezolid be considered for Gram positive organisms as first line antibiotics in empirical therapy while Carbapenems may be kept as reserve drugs should the first line drugs fail.

  16. Strain Dependent Genetic Networks for Antibiotic-Sensitivity in a Bacterial Pathogen with a Large Pan-Genome.

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    Tim van Opijnen

    2016-09-01

    Full Text Available The interaction between an antibiotic and bacterium is not merely restricted to the drug and its direct target, rather antibiotic induced stress seems to resonate through the bacterium, creating selective pressures that drive the emergence of adaptive mutations not only in the direct target, but in genes involved in many different fundamental processes as well. Surprisingly, it has been shown that adaptive mutations do not necessarily have the same effect in all species, indicating that the genetic background influences how phenotypes are manifested. However, to what extent the genetic background affects the manner in which a bacterium experiences antibiotic stress, and how this stress is processed is unclear. Here we employ the genome-wide tool Tn-Seq to construct daptomycin-sensitivity profiles for two strains of the bacterial pathogen Streptococcus pneumoniae. Remarkably, over half of the genes that are important for dealing with antibiotic-induced stress in one strain are dispensable in another. By confirming over 100 genotype-phenotype relationships, probing potassium-loss, employing genetic interaction mapping as well as temporal gene-expression experiments we reveal genome-wide conditionally important/essential genes, we discover roles for genes with unknown function, and uncover parts of the antibiotic's mode-of-action. Moreover, by mapping the underlying genomic network for two query genes we encounter little conservation in network connectivity between strains as well as profound differences in regulatory relationships. Our approach uniquely enables genome-wide fitness comparisons across strains, facilitating the discovery that antibiotic responses are complex events that can vary widely between strains, which suggests that in some cases the emergence of resistance could be strain specific and at least for species with a large pan-genome less predictable.

  17. Sensitive and Simplified Detection of Antibiotic Influence on the Dynamic and Versatile Changes of Fecal Short-Chain Fatty Acids.

    Science.gov (United States)

    Zhao, Xiaoya; Jiang, Zhenzuo; Yang, Fan; Wang, Yan; Gao, Xiumei; Wang, Yuefei; Chai, Xin; Pan, Guixiang; Zhu, Yan

    2016-01-01

    Short-chain fatty acids (SCFAs), produced by anaerobic fermentation of mainly indigestible dietary carbohydrates by gut microbiota, have a profound influence on intestinal function and host energy metabolism. Antibiotics may seriously disturb the balance of fecal SCFAs. To evaluate the impacts of antibiotics on fecal SCFAs produced by gut microbiota, a simple, reproducible and accurate gas chromatography (GC) method, which can simultaneously analyze seven SCFAs in fecal samples, was developed and validated. The ranges of detection and quantitation of the SCFAs reached 0.0868 ~ 0.393 and 0.261 ~ 1.18 μg·mL-1 respectively, in an optimized protocol for SCFAs extraction and analysis that used 10 mL 75% ethanol aqueous solution containing 1% HCl, without ultrasonication. The technique exhibited excellent intra-day (relative standard deviation (RSD) ≤ 2.54%) and inter-day (RSD ≤ 4.33%) precisions for all the SCFAs. Later, we administered broad-spectrum antibiotics, cefdinir or azithromycin to rats and analyzed the alterations in fecal SCFAs. The total amount, types and distribution of nearly all fecal SCFAs were significantly altered during the administration and even after withdrawal of the antibiotics in rats. The effects of cefdinir on the SCFAs were more pronounced than those of azithromycin. Our findings suggest SCFAs may serve as sensitive indicators to monitor the influences of antibiotics on SCFAs originated by intestinal bacteria. Our improved SCFAs analysis method is a potential platform for a standard clinical test of the effects of new antibiotics on SCFAs.

  18. Antibiotic therapy and Clostridium difficile infection – primum non nocere – first do no harm

    Directory of Open Access Journals (Sweden)

    Crowther GS

    2015-09-01

    Full Text Available Grace S Crowther,1 Mark H Wilcox1,2 1Faculty of Medicine and Health, University of Leeds, Leeds, UK; 2Department of Microbiology, Leeds Teaching Hospitals Trust, Leeds, UK Abstract: Treatment options for Clostridium difficile infection (CDI remain limited despite this usually nosocomial infection posing an urgent threat to public health. A major paradox of the management of CDI is the use of antimicrobial agents to treat infection, which runs the risk of prolonged gut microbiota perturbation and so recurrence of infection. Here, we explore alternative CDI treatment and prevention options currently available or in development. Notably, strategies that aim to reduce the negative effects of antibiotics on gut microbiota offer the potential to alter current antimicrobial stewardship approaches to preventing CDI. Keywords: treatment, prevention, CDI, SYN-004, vaccine, beta-lactams

  19. Radiorespirometric testing of antibiotic sensitivity in urinary tract infections: concise communication

    International Nuclear Information System (INIS)

    Singh, K.T.; Ganatra, R.D.; Shah, D.H.; Shanta, M.; Nimbkar, Y.S.; Gaitonde, B.B.; Dudani, R.A.; Jadav, S.K.; Acharya, V.N.

    1980-01-01

    A radiometric method, based on inhibition of 14 CO 2 release from bacterial metabolism of C-14-labeled glucose, was applied to test the susceptibility of urinary organisms to antibiotics. The testing was also carried out by the routine disc diffusion method after isolation of the organisms. Results of susceptibility to antibiotics could be obtained within 2 to 4 hr by the radiometric technique, compared with the 48 hr required for the disc method

  20. Sensitization of Staphylococcus aureus to methicillin and other antibiotics in vitro and in vivo in the presence of HAMLET.

    Directory of Open Access Journals (Sweden)

    Laura R Marks

    Full Text Available HAMLET (human alpha-lactalbumin made lethal to tumor cells is a protein-lipid complex from human milk with both tumoricidal and bactericidal activities. HAMLET exerts a rather specific bactericidal activity against some respiratory pathogens, with highest activity against Streptococcus pneumoniae, but lacks activity against most other bacterial pathogens, including Staphylococci. Still, ion transport associated with death in S. pneumoniae is also detected to a lower degree in insensitive organisms. In this study we demonstrate that HAMLET acts as an antimicrobial adjuvant that can increase the activity of a broad spectrum of antibiotics (methicillin, vancomycin, gentamicin and erythromycin against multi-drug resistant Staphylococcus aureus, to a degree where they become sensitive to those same antibiotics, both in antimicrobial assays against planktonic and biofilm bacteria and in an in vivo model of nasopharyngeal colonization. We show that HAMLET exerts these effects specifically by dissipating the proton gradient and inducing a sodium-dependent calcium influx that partially depolarizes the plasma membrane, the same mechanism induced during pneumococcal death. These effects results in an increased cell associated binding and/or uptake of penicillin, gentamicin and vancomycin, especially in resistant stains. Finally, HAMLET inhibits the increased resistance of methicillin seen under antibiotic pressure and the bacteria do not become resistant to the adjuvant, which is a major advantageous feature of the molecule. These results highlight HAMLET as a novel antimicrobial adjuvant with the potential to increase the clinical usefulness of antibiotics against drug resistant strains of S. aureus.

  1. Sensitization of Staphylococcus aureus to methicillin and other antibiotics in vitro and in vivo in the presence of HAMLET.

    Science.gov (United States)

    Marks, Laura R; Clementi, Emily A; Hakansson, Anders P

    2013-01-01

    HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a protein-lipid complex from human milk with both tumoricidal and bactericidal activities. HAMLET exerts a rather specific bactericidal activity against some respiratory pathogens, with highest activity against Streptococcus pneumoniae, but lacks activity against most other bacterial pathogens, including Staphylococci. Still, ion transport associated with death in S. pneumoniae is also detected to a lower degree in insensitive organisms. In this study we demonstrate that HAMLET acts as an antimicrobial adjuvant that can increase the activity of a broad spectrum of antibiotics (methicillin, vancomycin, gentamicin and erythromycin) against multi-drug resistant Staphylococcus aureus, to a degree where they become sensitive to those same antibiotics, both in antimicrobial assays against planktonic and biofilm bacteria and in an in vivo model of nasopharyngeal colonization. We show that HAMLET exerts these effects specifically by dissipating the proton gradient and inducing a sodium-dependent calcium influx that partially depolarizes the plasma membrane, the same mechanism induced during pneumococcal death. These effects results in an increased cell associated binding and/or uptake of penicillin, gentamicin and vancomycin, especially in resistant stains. Finally, HAMLET inhibits the increased resistance of methicillin seen under antibiotic pressure and the bacteria do not become resistant to the adjuvant, which is a major advantageous feature of the molecule. These results highlight HAMLET as a novel antimicrobial adjuvant with the potential to increase the clinical usefulness of antibiotics against drug resistant strains of S. aureus.

  2. Antibiotic Resistant Bacterial Isolates from Captive Green Turtles and In Vitro Sensitivity to Bacteriophages

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    Alessandro Delli Paoli Carini

    2017-01-01

    Full Text Available This study aimed to test multidrug resistant isolates from hospitalised green turtles (Chelonia mydas and their environment in North Queensland, Australia, for in vitro susceptibility to bacteriophages. Seventy-one Gram-negative bacteria were isolated from green turtle eye swabs and water samples. Broth microdilution tests were used to determine antibiotic susceptibility. All isolates were resistant to at least two antibiotics, with 24% being resistant to seven of the eight antibiotics. Highest resistance rates were detected to enrofloxacin (77% and ampicillin (69.2%. More than 50% resistance was also found to amoxicillin/clavulanic acid (62.5%, ceftiofur (53.8%, and erythromycin (53.3%. All the enriched phage filtrate mixtures resulted in the lysis of one or more of the multidrug resistant bacteria, including Vibrio harveyi and V. parahaemolyticus. These results indicate that antibiotic resistance is common in Gram-negative bacteria isolated from hospitalised sea turtles and their marine environment in North Queensland, supporting global concern over the rapid evolution of multidrug resistant genes in the environment. Using virulent bacteriophages as antibiotic alternatives would not only be beneficial to turtle health but also prevent further addition of multidrug resistant genes to coastal waters.

  3. Continuous infusion of antibiotics in critically ill patients.

    Science.gov (United States)

    Smuszkiewicz, Piotr; Szałek, Edyta; Tomczak, Hanna; Grześkowiak, Edmund

    2013-02-01

    Antibiotics are the most commonly used drugs in intensive care unit patients and their supply should be based on pharmacokinetic/pharmacodynamic rules. The changes that occur in septic patients who are critically ill may be responsible for subtherapeutic antibiotic concentrations leading to poorer clinical outcomes. Evolving in time the disturbed pathophysiology in severe sepsis (high cardiac output, glomerular hyperfiltration) and therapeutic interventions (e.g. haemodynamically active drugs, mechanical ventilation, renal replacement therapy) alters antibiotic pharmacokinetics mainly through an increase in the volume of distribution and altered drug clearance. The lack of new and efficacious drugs and increased bacterial resistance are current problems of contemporary antibiotic therapy. Although intermittent administration is a standard clinical practice, alternative methods of antibiotic administration are sought, which may potentialise effects and reduce toxicity as well as contribute to inhibition of bacterial resistance. A wide range of studies prove that the application of continuous infusion of time-dependent antibiotics (beta-lactams, glycopeptides) is more rational than standard intermittent administration. However, there are also studies which do not confirm the advantage of one method over the other. In spite of controversy the continuous administration of this group of antibiotics is common practice, because the results of both studies point to the higher efficacy of this method in critically ill patients. Authors reviewed the literature to determine whether any clinical benefits exist for administration of time-dependent antibiotics by continuous infusion. Definite specification of the clinical advantage of administration this way over standard dosage requires a large-scale multi-centre randomised controlled trial.

  4. Antibiotic resistance and virulence genes in coliform water isolates.

    Science.gov (United States)

    Stange, C; Sidhu, J P S; Tiehm, A; Toze, S

    2016-11-01

    Widespread fecal pollution of surface water may present a major health risk and a significant pathway for dissemination of antibiotic resistance bacteria. The River Rhine is one of the longest and most important rivers in Europe and an important raw water source for drinking water production. A total of 100 coliform isolates obtained from River Rhine (Germany) were examined for their susceptibility to seven antimicrobial agents. Resistances against amoxicillin, trimethoprim/sulfamethoxazole and tetracycline were detected in 48%, 11% and 9% of isolates respectively. The antibiotic resistance could be traced back to the resistance genes bla TEM , bla SHV , ampC, sul1, sul2, dfrA1, tet(A) and tet(B). Whereby, the ampC gene represents a special case, because its presence is not inevitably linked to a phenotypic antibiotic resistance. Multiple antibiotics resistance was often accompanied by the occurrence of class 1 or 2 integrons. E. coli isolates belonging to phylogenetic groups A and B1 (commensal) were more predominant (57%) compared to B2 and D groups (43%) which are known to carry virulent genes. Additionally, six E. coli virulence genes were also detected. However, the prevalence of virulence genes in the E. coli isolates was low (not exceeding 4.3% per gene) and no diarrheagenic E. coli pathotypes were detected. This study demonstrates that surface water is an important reservoir of ARGs for a number of antibiotic classes such as sulfonamide, trimethoprim, beta-lactam-antibiotics and tetracycline. The occurrence of antibiotic resistance in coliform bacteria isolated from River Rhine provides evidence for the need to develop management strategies to limit the spread of antibiotic resistant bacteria in aquatic environment. Copyright © 2016 Elsevier GmbH. All rights reserved.

  5. Bacteriological Study of 100 Cases of Pyodermas with Special Reference to Staphylococci, Their Antibiotic Sensitivity and Phage Pattern

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    T V Ramani

    1980-01-01

    Full Text Available One hundred new cases of pyodenna attending King George Hospital, Vishakhapatnam were investigated bacteriologically with antibiotic sensitivity of all the strains isolated and phage typing of coagulm positive staphylocci. Among these 50 had impetigo and 15 each ahd furunculosis and fouiculitis. The remaining included various other clinical entities. Children under 10 years were observed to have high incidence of pyoderma. A total of 88 strains of staphylococci (77 coagulase positive and 11 coagulase negative strains 25 strains of beta haemolytic streptococci and 3 strains of Klebsiella were isolated. Staphylococci were found to be the commonest aetiological agents either single or in association with other organisms. Of the 76 strains of coagulase positive staphylococci 32 strains were not phage typable and among the 44 typable strains 17 (38% belonged to group III and 15 (36.5% to mixed group. Coagulase positive staphylococci showed high sensitivity to garamycin, kanamycin and erythromycin and high resistance to penicillin and streptomycin. Multiple drug resistance was also high among these strains. Coagulase negative staphylococci were found to be more sensitive with less incidence of multiple drug resistance. Most of multiple drug resistant strains belonged to group III phage types. Beta haemolytic streptococci were found to be highly sensitive to all the antibiotics tested.

  6. DALI: Defining Antibiotic Levels in Intensive care unit patients: a multi-centre point of prevalence study to determine whether contemporary antibiotic dosing for critically ill patients is therapeutic.

    Science.gov (United States)

    Roberts, Jason A; De Waele, Jan J; Dimopoulos, George; Koulenti, Despoina; Martin, Claude; Montravers, Philippe; Rello, Jordi; Rhodes, Andrew; Starr, Therese; Wallis, Steven C; Lipman, Jeffrey

    2012-07-06

    The clinical effects of varying pharmacokinetic exposures of antibiotics (antibacterials and antifungals) on outcome in infected critically ill patients are poorly described. A large-scale multi-centre study (DALI Study) is currently underway describing the clinical outcomes of patients achieving pre-defined antibiotic exposures. This report describes the protocol. DALI will recruit over 500 patients administered a wide range of either beta-lactam or glycopeptide antibiotics or triazole or echinocandin antifungals in a pharmacokinetic point-prevalence study. It is anticipated that over 60 European intensive care units (ICUs) will participate. The primary aim will be to determine whether contemporary antibiotic dosing for critically ill patients achieves plasma concentrations associated with maximal activity. Secondary aims will compare antibiotic pharmacokinetic exposures with patient outcome and will describe the population pharmacokinetics of the antibiotics included. Various subgroup analyses will be conducted to determine patient groups that may be at risk of very low or very high concentrations of antibiotics. The DALI study should inform clinicians of the potential clinical advantages of achieving certain antibiotic pharmacokinetic exposures in infected critically ill patients.

  7. DALI: Defining Antibiotic Levels in Intensive care unit patients: a multi-centre point of prevalence study to determine whether contemporary antibiotic dosing for critically ill patients is therapeutic

    Directory of Open Access Journals (Sweden)

    Roberts Jason A

    2012-07-01

    Full Text Available Abstract Background The clinical effects of varying pharmacokinetic exposures of antibiotics (antibacterials and antifungals on outcome in infected critically ill patients are poorly described. A large-scale multi-centre study (DALI Study is currently underway describing the clinical outcomes of patients achieving pre-defined antibiotic exposures. This report describes the protocol. Methods DALI will recruit over 500 patients administered a wide range of either beta-lactam or glycopeptide antibiotics or triazole or echinocandin antifungals in a pharmacokinetic point-prevalence study. It is anticipated that over 60 European intensive care units (ICUs will participate. The primary aim will be to determine whether contemporary antibiotic dosing for critically ill patients achieves plasma concentrations associated with maximal activity. Secondary aims will compare antibiotic pharmacokinetic exposures with patient outcome and will describe the population pharmacokinetics of the antibiotics included. Various subgroup analyses will be conducted to determine patient groups that may be at risk of very low or very high concentrations of antibiotics. Discussion The DALI study should inform clinicians of the potential clinical advantages of achieving certain antibiotic pharmacokinetic exposures in infected critically ill patients.

  8. The sensitivities to first-line antibiotic therapy of the common urinary ...

    African Journals Online (AJOL)

    Background: Urinary tract infections (UTIs) are among the most common human infections. Many urinary tract bacteria are capable of expressing drug resistance. Resistant bacteria may be present from the commencement of the infection or may develop during treatment. This study focused on the problem of antibiotic ...

  9. Diversity and antibiotic resistance patterns of Sphingomonadaceae isolates from drinking water.

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2011-08-15

    Sphingomonadaceae (n = 86) were isolated from a drinking water treatment plant (n = 6), tap water (n = 55), cup fillers for dental chairs (n = 21), and a water demineralization filter (n = 4). The bacterial isolates were identified based on analysis of the 16S rRNA gene sequence, and intraspecies variation was assessed on the basis of atpD gene sequence analysis. The isolates were identified as members of the genera Sphingomonas (n = 27), Sphingobium (n = 28), Novosphingobium (n = 12), Sphingopyxis (n = 7), and Blastomonas (n = 12). The patterns of susceptibility to five classes of antibiotics were analyzed and compared for the different sites of isolation and taxonomic groups. Colistin resistance was observed to be intrinsic (92%). The highest antibiotic resistance prevalence values were observed in members of the genera Sphingomonas and Sphingobium and for beta-lactams, ciprofloxacin, and cotrimoxazole. In tap water and in water from dental chairs, antibiotic resistance was more prevalent than in the other samples, mainly due to the predominance of isolates of the genera Sphingomonas and Sphingobium. These two genera presented distinct patterns of association with antibiotic resistance, suggesting different paths of resistance development. Antibiotic resistance patterns were often related to the species rather than to the site or strain, suggesting the importance of vertical resistance transmission in these bacteria. This is the first study demonstrating that members of the family Sphingomonadaceae are potential reservoirs of antibiotic resistance in drinking water.

  10. Diversity and Antibiotic Resistance Patterns of Sphingomonadaceae Isolates from Drinking Water▿

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C.; Manaia, Célia M.

    2011-01-01

    Sphingomonadaceae (n = 86) were isolated from a drinking water treatment plant (n = 6), tap water (n = 55), cup fillers for dental chairs (n = 21), and a water demineralization filter (n = 4). The bacterial isolates were identified based on analysis of the 16S rRNA gene sequence, and intraspecies variation was assessed on the basis of atpD gene sequence analysis. The isolates were identified as members of the genera Sphingomonas (n = 27), Sphingobium (n = 28), Novosphingobium (n = 12), Sphingopyxis (n = 7), and Blastomonas (n = 12). The patterns of susceptibility to five classes of antibiotics were analyzed and compared for the different sites of isolation and taxonomic groups. Colistin resistance was observed to be intrinsic (92%). The highest antibiotic resistance prevalence values were observed in members of the genera Sphingomonas and Sphingobium and for beta-lactams, ciprofloxacin, and cotrimoxazole. In tap water and in water from dental chairs, antibiotic resistance was more prevalent than in the other samples, mainly due to the predominance of isolates of the genera Sphingomonas and Sphingobium. These two genera presented distinct patterns of association with antibiotic resistance, suggesting different paths of resistance development. Antibiotic resistance patterns were often related to the species rather than to the site or strain, suggesting the importance of vertical resistance transmission in these bacteria. This is the first study demonstrating that members of the family Sphingomonadaceae are potential reservoirs of antibiotic resistance in drinking water. PMID:21705522

  11. Study of Pre-disposing Factors of Acute Exacerbation of Chronic Obstructive Pulmonary Disease and Antibiotic Prescribing Pattern with Reference to Antibiotic Sensitivity Test.

    Science.gov (United States)

    Shrestha, R; Shrestha, B; Shakya Shrestha, S; Pant, A; Prajapati, B; Karmacharya, B M

    2015-01-01

    Background Chronic Obstructive Pulmonary Disease (COPD) affects about 329 million people worldwide, which is nearly 5% of the entire global population. In the context of Nepal, COPD accounts for 43% of the non-communicable disease burden and 2.56% of hospitalizations. Various pre-disposing factors like bacterial, viral, fungal, smoking, occupational exposures and genetic factors have been proposed to precipitate COPD and its exacerbation though, the definitive pre-disposing factors and factors related to acute exacerbation have not been determined in the context of Nepal. Objective To find out the pre-disposing factors and the related causative agents for COPD. Method A cross sectional study was conducted in a tertiary care hospital. Patients of all age group who were diagnosed as COPD and admitted in the hospital were included in this study. Patients were interviewed using structured questionnaire. The sociodemographic data including personal and medical history were recorded from those participants. In addition, sputum from those patients was sent for culture to investigate the possible responsible pathogens as well as its antibiotic sensitivity pattern. Result A total of 150 patients having Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) who have admitted from either emergency or out-patient department of the hospital were included in this study. Among the total number of patients, more than half of them were female (n=82). In addition, analysis of occupations shows that most of them were either farmer (36.0%) or housewife (30.7%). In total studied patients (n=150), most of them were using traditional firewood (83%) for cooking purpose and majority of patients (91%) were smokers. Most of the sputum samples show growth of gram-positive cocci (26.7%) and gram negative bacilli (27.5%). Considering the overall sensitivity pattern, the higher sensitivity was recorded for Co-trimoxazole and Ciprofloxacin while higher rate of resistance was noted

  12. Ammonia produced by bacterial colonies promotes growth of ampicillin-sensitive Serratia sp. by means of antibiotic inactivation.

    Science.gov (United States)

    Cepl, Jaroslav; Blahůšková, Anna; Cvrčková, Fatima; Markoš, Anton

    2014-05-01

    Volatiles produced by bacterial cultures are known to induce regulatory and metabolic alterations in nearby con-specific or heterospecific bacteria, resulting in phenotypic changes including acquisition of antibiotic resistance. We observed unhindered growth of ampicillin-sensitive Serratia rubidaea and S. marcescens on ampicillin-containing media, when exposed to volatiles produced by dense bacterial growth. However, this phenomenon appeared to result from pH increase in the medium caused by bacterial volatiles rather than alterations in the properties of the bacterial cultures, as alkalization of ampicillin-containing culture media to pH 8.5 by ammonia or Tris exhibited the same effects, while pretreatment of bacterial cultures under the same conditions prior to antibiotic exposure did not increase ampicillin resistance. Ampicillin was readily inactivated at pH 8.5, suggesting that observed bacterial growth results from metabolic alteration of the medium, rather than an active change in the target bacterial population (i.e. induction of resistance or tolerance). However, even such seemingly simple mechanism may provide a biologically meaningful basis for protection against antibiotics in microbial communities growing on semi-solid media. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  13. Differential sensitivity of pigmented and non-pigmented marine bacteria to metals and antibiotics

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.; Chandramohan, D.; LokaBharathi, P.A.

    . Appl. em'ir. Microbiol. 33, 975-976. Nelson J. D. Jr and Colwell R. R. (1975) The ecology of mercury resistant bacteria in Chesapeake bay. Microbioi. Ecol. 1, 191-218. Oison B. H. and Thornton I. (1982) The resistance patterns to metals... to metals em- ploying epifluorescent microscopy. J. microbiol. Met& 7, 143-155. Zemelman R., Silva J. and Herriques, M. (1980) Antibiotic resistant bacteria in seawater from Concepcion Bay. Archs Biol. Exp. 13, 121. ...

  14. Factors influencing antibiotic prescribing habits and use of sensitivity testing amongst veterinarians in Europe

    OpenAIRE

    De Briyne, N.; Atkinson, J.; Pokludov?, L.; Borriello, S. P.; Price, S.

    2013-01-01

    The Heads of Medicines Agencies and the Federation of Veterinarians of Europe undertook a survey to gain a better insight into the decision-making process of veterinarians in Europe when deciding which antibiotics to prescribe. The survey was completed by 3004 practitioners from 25 European countries. Analysis was to the level of different types of practitioner (food producing (FP) animals, companion animals, equines) and country for Belgium, Czech Republic, France, Germany, Spain, Sweden and...

  15. Repeat Rifaximin for Irritable Bowel Syndrome: No Clinically Significant Changes in Stool Microbial Antibiotic Sensitivity.

    Science.gov (United States)

    Pimentel, M; Cash, B D; Lembo, A; Wolf, R A; Israel, R J; Schoenfeld, P

    2017-09-01

    Rifaximin has demonstrated efficacy and safety for diarrhea-predominant irritable bowel syndrome (IBS-D). To determine the rifaximin repeat treatment effect on fecal bacterial antibiotic susceptibility. Patients with IBS in Trial 3 (TARGET 3) study who responded to open-label rifaximin 550 mg three times daily for 2 weeks, with symptom recurrence within 18 weeks, were randomized to double-blind treatment: two 2-week repeat courses of rifaximin or placebo, separated by 10 weeks. Prospective stool sample collection occurred before and after open-label rifaximin, before and after the first repeat course, and at the end of the study. Susceptibility testing was performed with 11 antibiotics, including rifaximin and rifampin, using broth microdilution or agar dilution methods. Of 103 patients receiving open-label rifaximin, 73 received double-blind rifaximin (n = 37) or placebo (n = 36). A total of 1429 bacterial and yeast isolates were identified, of which Bacteroidaceae (36.7%) and Enterobacteriaceae (33.9%) were the most common. In the double-blind phase, Clostridium difficile was highly susceptible to rifaximin [minimum inhibitory concentration (MIC) range 0.008-1 µg/mL] and rifampin (MIC range 0.004-0.25 µg/mL). Following double-blind rifaximin treatment, Staphylococcus isolates remained susceptible to rifaximin at all visits (MIC 50 range ≤0.06-32 µg/mL). Rifaximin exposure was not associated with long-term cross-resistance of Bacteroidaceae, Enterobacteriaceae, and Enterococcaceae to rifampin or nonrifamycin antibiotics tested. In this study, short-term repeat treatment with rifaximin has no apparent long-term effect on stool microbial susceptibility to rifaximin, rifampin, and nonrifamycin antibiotics. CLINICALTRIALS. NCT01543178.

  16. RESEARCH IN SENSITIVITY TO ANTIBIOTICS, ANTISEPTICS IN PSEUDOMONAS AERUGINOSA STRAINS ISOLATED FROM PATIENTS WITH INFECTIOUS COMPLICATIONS

    OpenAIRE

    O. A. Nazarchuk; D. V. Paliy; N. I. Osadchuk

    2017-01-01

    Background. Infections caused by Pseudomonas are one of the topical issues of medicine. Objective. The aim of the research was to study sensityvity to antibiotics, antiseptics of P. aeruginosa clinical strains that cause infectious complications in patients with burns. Methods. Microbiological study of biological material, received from 435 patients with burns of the 3rd-4th stages (2011-2015 years). In early terms of burn disease 127 clinical strains of P. aeruginosa were isolated fr...

  17. Effects of temperature, genetic variation and species competition on the sensitivity of algae populations to the antibiotic enrofloxacin.

    Science.gov (United States)

    Rico, Andreu; Zhao, Wenkai; Gillissen, Frits; Lürling, Miquel; Van den Brink, Paul J

    2018-02-01

    Primary producers are amongst the most sensitive organisms to antibiotic pollution in aquatic ecosystems. To date, there is little information on how different environmental conditions may affect their sensitivity to antibiotics. In this study we assessed how temperature, genetic variation and species competition may affect the sensitivity of the cyanobacterium Microcystis aeruginosa and the green-algae Scenedesmus obliquus to the antibiotic enrofloxacin. First, we performed single-species tests to assess the toxicity of enrofloxacin under different temperature conditions (20°C and 30°C) and to assess the sensitivity of different species strains using a standard temperature (20°C). Next, we investigated how enrofloxacin contamination may affect the competition between M. aeruginosa and S. obliquus. A competition experiment was performed following a full factorial design with different competition treatments, defined as density ratios (i.e. initial bio-volume of 25/75%, 10/90% and 1/99% of S. obliquus/M. aeruginosa, respectively), one 100% S. obliquus treatment and one 100% M. aeruginosa treatment, and four different enrofloxacin concentrations (i.e. control, 0.01, 0.05 and 0.10mg/L). Growth inhibition based on cell number, bio-volume, chlorophyll-a concentration as well as photosynthetic activity were used as evaluation endpoints in the single-species tests, while growth inhibition based on measured chlorophyll-a was primarily used in the competition experiment. M. aeruginosa photosynthetic activity was found to be the most sensitive endpoint to enrofloxacin (EC50-72h =0.02mg/L), followed by growth inhibition based on cell number. S. obliquus was found to be slightly more sensitive at 20°C than at 30°C (EC50-72h cell number growth inhibition of 38 and 41mg/L, respectively), whereas an opposite trend was observed for M. aeruginosa (0.047 and 0.037mg/L, respectively). Differences in EC50-72h values between algal strains of the same species were within a factor

  18. The sensitivity to antibiotics of strains of group B streptococcus isolates from pregnant women in Belgrade

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    Jovanović Luka

    2016-01-01

    Full Text Available Introduction: Group B streptococcus (GBS is a significant human pathogen. GBS colonizes the vagina and it is one of the most important causes of early neonatal sepsis and meningitis. In many countries, screening of pregnant women and intrapartal use of antibiotics are common practice. Macrolide and lincosamide resistant strains of GBS are a significant problem, because these antibiotics are the second line therapy in case of penicillin allergy. Aim: Our aim was to investigate the frequency of antibiotic resistant strains of GBS and to detect macrolide resistance phenotypes in GBS strains obtained from pregnant women in Belgrade. Material and Methods: 105 GBS isolates were obtained from vaginal swabs of pregnant women attending two Gynecology and Obstetrics Centers in Belgrade. The isolates were tested for antimicrobial susceptibility pattern and D test were performed on Mueller Hinton agar. Results: Macrolide and lincosamide resistance was found in 30.4 %, and 23.8 % of isolates, respectively. There was a high frequency of tetracycline resistant strains (88.6 %. Most frequent macrolide resistant phenotype was iMLSb (macrolide and inducibile lincosamide resistance (62.4%. Conclusion: The results of our study indicate that there is a high level of macrolide resistance among GBS isolates in Serbia and the active surveillance is needed.

  19. Surgical site infection in orthopedic implants and its common bacteria with their sensitivities to antibiotics, in open reduction internal fixation

    International Nuclear Information System (INIS)

    Shah, M.Q.; Zardad, M.S.; Khan, A.; Ahmed, S.; Awan, A. S.; Mohammad, T.

    2017-01-01

    Surgical site infection in orthopaedic implants is a major problem, causing long hospital stay, cost to the patient and is a burden on health care facilities. It increases rate of non-union, osteomyelitis, implant failure, sepsis, multiorgan dysfunction and even death. Surgical site infection is defined as pain, erythema, swelling and discharge from wound site. Surgical site infection in orthopaedic implants is more challenging to the treating orthopaedic surgeon as the causative organism is protected by a biofilm over the implant's surface. Antibiotics cannot cross this film to reach the bacteria's, causing infection. Method: This descriptive case series study includes 132 patients of both genders with ages between 13 years to 60 years conducted at Orthopaedic Unit, Ayub Medical College, Abbottabad from 1st October 2015 to 31st March 2016. Patients with close fractures of long bones were included in the study to determine the frequency of surgical site infection in orthopaedic implants and the type of bacteria involved and their sensitivity to various antibiotics. All implants were of stainless steel. The implants used were Dynamic hip screws, Dynamic compression screws, plates, k-wires, Interlocking nails, SIGN nails, Austin Moore prosthesis and tension band wires. Pre-op and post-op antibiotics used were combination of Sulbactum and Cefoperazone which was given 1 hour before surgery and continued for 72 hours after surgery. Patients were followed up to 4 weeks. Pus was taken on culture stick, from those who developed infection. Results were entered in the pro forma. Results: A total of 132 patients of long bone fractures, who were treated with open reduction and internal fixation, were studied. Only 7 patients developed infection. Staphylococcus Aureus was isolated from all 7 patients. Staphylococcus aureus was sensitive to Linezolid, Fusidic Acid, and vancomycin. Cotrimoxazole, tetracycline, Gentamycin and Clindamycin were partially effective. Conclusion

  20. Association of Pattern of Bacteria Sensitivity During the Empirical Antibiotics Use to the Achievement of Clinical Outcome in Pediatric Patients with Pneumonia

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    Vesara A. Gatera

    2014-12-01

    Full Text Available Pneumonia is one of infectious diseases that require a comprehensive and effective effort in its treatment, including in the use of empirical antibiotics. The use of empirical antibiotics should be based on patterns of sensitivity toward bacteria. The aim of this study was to evaluate the use of antibiotics based on the sensitivity patterns by clinical outcomes as the goal of treatment. This study was conducted in Hasan Sadikin Hospital Bandung in October–December 2013 using a retrospective cross-sectional study design. Secondary data were obtained from medical records during January 2011–December 2012. This study consisted of 24 patients with positive culture test and received antibiotic prescription. The results showed the percentage of the use of cefotaxime-ampicillin (37.5%, cefotaxime (33.3%, ceftriaxone (20.8%, and Ampicillin (8.4%. The most influential antibiotics for achieving clinical outcome using 95% confidence level is combination of cefotaxime-ampiciline (P=0.044 with 77.7% sensitivity level. This study suggested that the pattern of antibiotic sensitivity affected the clinical outcomes of pediatric patients with pneumonia.

  1. Antibiotic Residues in Milk from Three Popular Kenyan Milk Vending Machines.

    Science.gov (United States)

    Kosgey, Amos; Shitandi, Anakalo; Marion, Jason W

    2018-05-01

    Milk vending machines (MVMs) are growing in popularity in Kenya and worldwide. Milk vending machines dispense varying quantities of locally sourced, pasteurized milk. The Kenya Dairy Board has a regulatory framework, but surveillance is weak because of several factors. Milk vending machines' milk is not routinely screened for antibiotics, thereby increasing potential for antibiotic misuse. To investigate, a total of 80 milk samples from four commercial providers ( N = 25), street vendors ( N = 21), and three MVMs ( N = 34) were collected and screened in Eldoret, Kenya. Antibiotic residue surveillance occurred during December 2016 and January 2017 using Idexx SNAP ® tests for tetracyclines, sulfamethazine, beta-lactams, and gentamicin. Overall, 24% of MVM samples and 24% of street vendor samples were presumably positive for at least one antibiotic. No commercial samples were positive. Research into cost-effective screening methods and increased monitoring by food safety agencies are needed to uphold hazard analysis and critical control point for improving antibiotic stewardship throughout the Kenyan private dairy industry.

  2. In Vitro Sensitivity Test in Antibiotics from the Fermentation Process in a Sugar-Alcohol Plant in the State of Paraná, Brazil

    OpenAIRE

    Lopes, Murilo Brandão; Faculdade de Apucarana – FAP; Silva, Thaís Medeiros Boldrin; Faculdade Metropolitana de Maringá – UNIFAMMA

    2011-01-01

    Since the development of different types of microorganisms is common during the fermentation process in sugar-alcohol plants, due to the processing states of prime matter, microbiological control is mandatory. In vitro sensitivity test is highly important for the fermentation process at sugar-alcohol plants since the type of antibiotic with the best antibacterial activity is evaluated. The test classifies antibiotics through their effects, namely, efficient, less efficient, slightly efficient...

  3. Antibiotic resistome in a large-scale healthy human gut microbiota deciphered by metagenomic and network analyses.

    Science.gov (United States)

    Feng, Jie; Li, Bing; Jiang, Xiaotao; Yang, Ying; Wells, George F; Zhang, Tong; Li, Xiaoyan

    2018-01-01

    The human gut microbiota is an important reservoir of antibiotic resistance genes (ARGs). A metagenomic approach and network analysis were used to establish a comprehensive antibiotic resistome catalog and to obtain co-occurrence patterns between ARGs and microbial taxa in fecal samples from 180 healthy individuals from 11 different countries. In total, 507 ARG subtypes belonging to 20 ARG types were detected with abundances ranging from 7.12 × 10 -7 to 2.72 × 10 -1 copy of ARG/copy of 16S-rRNA gene. Tetracycline, multidrug, macrolide-lincosamide-streptogramin, bacitracin, vancomycin, beta-lactam and aminoglycoside resistance genes were the top seven most abundant ARG types. The multidrug ABC transporter, aadE, bacA, acrB, tetM, tetW, vanR and vanS were shared by all 180 individuals, suggesting their common occurrence in the human gut. Compared to populations from the other 10 countries, the Chinese population harboured the most abundant ARGs. Moreover, LEfSe analysis suggested that the MLS resistance type and its subtype 'ermF' were representative ARGs of the Chinese population. Antibiotic inactivation, antibiotic target alteration and antibiotic efflux were the dominant resistance mechanism categories in all populations. Procrustes analysis revealed that microbial phylogeny structured the antibiotic resistome. Co-occurrence patterns obtained via network analysis implied that 12 species might be potential hosts of 58 ARG subtypes. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Do antibiotics decrease implant failure and postoperative infections? A systematic review and meta-analysis.

    Science.gov (United States)

    Ata-Ali, J; Ata-Ali, F; Ata-Ali, F

    2014-01-01

    The purpose of this study was to systematically review and perform a comprehensive meta-analysis of the current literature to answer the following question: among patients receiving dental implants, does the use of antibiotics, when compared with a control group, reduce the frequency of implant failure and postoperative infection? A manual and electronic PubMed search of the literature was made to identify randomized controlled trials (RCTs) on the efficacy of antibiotics compared with a control group (not receiving antibiotics or receiving placebo). Four RCTs were included in the final review. These four RCTs grouped a total of 2063 implants and a total of 1002 patients. Antibiotic use significantly lowered the implant failure rate (P = 0.003), with an odds ratio of 0.331, implying that antibiotic treatment reduced the odds of failure by 66.9%. The number needed to treat (NNT) to prevent one patient from having an implant failure was 48 (95% confidence interval 31-109). In contrast, antibiotic use did not significantly reduce the incidence of postoperative infection (P = 0.754). Based on the results of this meta-analysis, and pending further research in the field, it can be concluded that there is evidence in favour of systematic antibiotic use in patients receiving dental implants, since such treatment significantly reduces implant failure. In contrast, antibiotic use does not exert a significant preventive effect against postoperative infection. Our recommendations for future research focus on the performance of large-scale RCTs to identify the best choice of antibiotic, timing of administration, and dose. Increased effort is also required to reach consensus and define the most effective antibiotic treatment protocol for patients who are allergic to beta-lactams and for those who are not. Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. Febrile neutropenia in paediatric peripheral blood stem cell transplantation, in vitro sensitivity data and clinical response to empirical antibiotic therapy

    International Nuclear Information System (INIS)

    Ansari, S.H.; Nasim, S.; Ahmed, A.; Irfan, M.; Ishaque, A.; Farzana, T.; Panjwani, V.K.; Taj, M.; Shamsi, T.S.

    2006-01-01

    To find the in-vitro sensitivity data and clinical response in order to determine the changes required in empiric antibiotic therapy for management of febrile neutropenia in paediatric patients undergoing peripheral blood stem cell transplantation. All patients were treated according to institutional protocol for febrile neutropenia. Empirical antibiotics include Ceftriaxone and Amikacin. In non-responders, changes made included Imipenem and Amikacin, Piperacillin Tazobactum/Tiecoplanin or Vancomycin/Cloxacilin/Ceftazidime. In non-responders, amphotaracin was added until recovery. Out of 52 patients, 5 did not develop any fever; in the remaining 47 patients there were 57 episodes of febrile neutropenia. The mean days of febrile episodes were 4.71 (range 3-8). Fever of unknown origin (FUO) occurred in 31 (54.3%) episodes. Microbiologically documented infection (MDI) occurred in 17 (29.8%) episodes of fever. Clinically documented infection (CDI) occurred in 9 (15.7%) episodes. Gram-negative organisms were isolated in 10 while gram-positive organisms in 7. Klebseilla, S. aureus were the most common isolates. Empirical therapy was effective in 12 of the 33 (36%) episodes. Out of 28, 26 (92%) responded to Imipenem/Amikacin as second line therapy while those who received any other second line combination, only 11 out of 22 (50%) showed response. Systemic Amphotericin was used in 4 patients, 2 responded. Infection related mortality rate was 4%. (author)

  6. Rv2477c is an antibiotic-sensitive manganese-dependent ABC-F ATPase in Mycobacterium tuberculosis.

    Science.gov (United States)

    Daniel, Jaiyanth; Abraham, Liz; Martin, Amanda; Pablo, Xyryl; Reyes, Shelby

    2018-01-01

    The Rv2477c protein of Mycobacterium tuberculosis (Mtb) belongs to the ATP-binding cassette (ABC) subfamily F that contains proteins with tandem nucleotide-binding domains but lacking transmembrane domains. ABC-F subfamily proteins have been implicated in diverse cellular processes such as translation, antibiotic resistance, cell growth and nutrient sensing. In order to investigate the biochemical characteristics of Rv2477c, we expressed it in Escherichia coli, purified it and characterized its enzymatic functions. We show that Rv2477c displays strong ATPase activity (V max  = 45.5 nmol/mg/min; K m  = 90.5 μM) that is sensitive to orthovanadate. The ATPase activity was maximal in the presence of Mn 2+ at pH 5.2. The Rv2477c protein was also able to hydrolyze GTP, TTP and CTP but at lower rates. Glutamate to glutamine substitutions at amino acid residues 185 and 468 in the two Walker B motifs of Rv2477c severely inhibited its ATPase activity. The antibiotics tetracycline and erythromycin, which target protein translation, were able to inhibit the ATPase activity of Rv2477c. We postulate that Rv2477c could be involved in mycobacterial protein translation and in resistance to tetracyclines and macrolides. This is the first report of the biochemical characterization of an ABC-F subfamily protein in Mtb. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. COMMON ORGANISMS AND ANTIBIOTIC SENSITIVITY OF E COLI IN URINARY TRACT INFECTION, IN A TERTIARY CARE TEACHING HOSPITAL, NORTHERN KERALA

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    Shanavas

    2015-11-01

    Full Text Available Urinary tract infection (UTI includes a spectrum of Asymptomatic Bacteruria (ABU, Cystitis, Prostitis and Pyelonephritis. Except in ABU, UTI is represented by symptomatic disease that warrants antimicrobial therapy. 1 Many of the studies have shown increasing antibiotic resistance to these agents. This study consists of a retrospective observational study of culture and sensitivity of 150 urinary samples, collected from patients who presented with symptoms of UTI, in a tertiary care teaching hospital, Northern Kerala, irrespective of their age and sex for a period of six months from June 2015 to November 2015. These results are then analyzed to find common organisms causing UTI in different age groups in either sex and their respective antibiotic resistance are noted. Out of 150 urinary samples 69.34% were sterile, while 30.66% were culture positive. Among the culture positive patients sex distribution was almost equal, with a slight female predominance, having a contribution of 54.35% females and 45.65% males. The most common organism was found to be E.coli, which contributed more than 50 per cent of total culture positivity (54.35%. Others include Staphylococci, Klebsiella Pnuemoniae, Proteus species, Pseudomonas, Enterococci, Candida Albicans etc. Collateral damage is an ecological adverse effect that resist the use of a highly efficacious drug to be considered as first line agent. Our study shows that drugs causing minimal collateral damages like Nitrofurantoin and Fosfomycin can be used as first line agent for treatment of UTI.

  8. Absence of penicillin-binding protein 4 from an apparently normal strain of Bacillus subtilis.

    OpenAIRE

    Buchanan, C E

    1987-01-01

    The phenotype of a Bacillus subtilis 168 strain with no detectable penicillin-binding protein 4 was examined. Despite the fact that penicillin-binding protein 4 is one of the most penicillin-sensitive proteins in the species, its apparent loss had no obvious effect on the organism or its susceptibility to various beta-lactam antibiotics.

  9. Antibiotic resistance genes in anaerobic bacteria isolated from primary dental root canal infections.

    Science.gov (United States)

    Rôças, Isabela N; Siqueira, José F

    2012-12-01

    Fourty-one bacterial strains isolated from infected dental root canals and identified by 16S rRNA gene sequence were screened for the presence of 14 genes encoding resistance to beta-lactams, tetracycline and macrolides. Thirteen isolates (32%) were positive for at least one of the target antibiotic resistance genes. These strains carrying at least one antibiotic resistance gene belonged to 11 of the 26 (42%) infected root canals sampled. Two of these positive cases had two strains carrying resistance genes. Six out of 7 Fusobacterium strains harbored at least one of the target resistance genes. One Dialister invisus strain was positive for 3 resistance genes, and 4 other strains carried two of the target genes. Of the 6 antibiotic resistance genes detected in root canal strains, the most prevalent were blaTEM (17% of the strains), tetW (10%), and ermC (10%). Some as-yet-uncharacterized Fusobacterium and Prevotella isolates were positive for blaTEM, cfxA and tetM. Findings demonstrated that an unexpectedly large proportion of dental root canal isolates, including as-yet-uncharacterized strains previously regarded as uncultivated phylotypes, can carry antibiotic resistance genes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Marinopyrrole Derivatives as Potential Antibiotic Agents against Methicillin-Resistant Staphylococcus aureus (II

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    Rongshi Li

    2013-08-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA continues to be a major problem, causing severe and intractable infections worldwide. MRSA is resistant to all beta-lactam antibiotics, and alternative treatments are limited. A very limited number of new antibiotics have been discovered over the last half-century, novel agents for the treatment of MRSA infections are urgently needed. Marinopyrrole A was reported to show antibiotic activity against MRSA in 2008. After we reported the first total synthesis of (±-marinopyrrole A, we designed and synthesized a series of marinopyrrole derivatives. Our structure activity relationship (SAR studies of these novel derivatives against a panel of Gram-positive pathogens in antibacterial assays have revealed that a para-trifluoromethyl analog (33 of marinopyrrole A is ≥63-, 8-, and 4-fold more potent than vancomycin against methicillin-resistant Staphylococcus epidermidis (MRSE, methicillin-susceptible Staphylococcus aureus (MSSA and MRSA, respectively. The results provide valuable information in the search for new-generation antibiotics.

  11. Fluorescent Metal-Organic Framework (MOF) as a Highly Sensitive and Quickly Responsive Chemical Sensor for the Detection of Antibiotics in Simulated Wastewater.

    Science.gov (United States)

    Zhu, Xian-Dong; Zhang, Kun; Wang, Yu; Long, Wei-Wei; Sa, Rong-Jian; Liu, Tian-Fu; Lü, Jian

    2018-02-05

    A Zn(II)-based fluorescent metal-organic framework (MOF) was synthesized and applied as a highly sensitive and quickly responsive chemical sensor for antibiotic detection in simulated wastewater. The fluorescent chemical sensor, denoted FCS-1, exhibited enhanced fluorescence derived from its highly ordered, 3D MOF structure as well as excellent water stability in the practical pH range of simulated antibiotic wastewater (pH = 3.0-9.0). Remarkably, FCS-1 was able to effectively detect a series of sulfonamide antibiotics via photoinduced electron transfer that caused detectable fluorescence quenching, with fairly low detection limits. Two influences impacting measurements related to wastewater treatment and water quality monitoring, the presence of heavy-metal ions and the pH of solutions, were studied in terms of fluorescence quenching, which was nearly unaffected in sulfonamide-antibiotic detection. Additionally, the effective detection of sulfonamide antibiotics was rationalized by the theoretical computation of the energy bands of sulfonamide antibiotics, which revealed a good match between the energy bands of FCS-1 and sulfonamide antibiotics, in connection with fluorescence quenching in this system.

  12. Antimicrobial Activity and Antibiotic Sensitivity of Three Isolates of Lactic Acid Bacteria From Fermented Fish Product, Budu

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    Liasi, S. A.

    2009-01-01

    Full Text Available Three isolates of lactic acid bacteria (LAB from the fermented food product, Budu, were identified as genus lactobacillus (Lactobacillus casei LA17, Lactobacillus plantarum LA22 and L. paracasei LA02, and the highest population was Lb. paracasei LA02. The antibacterial agent produced by the isolates inhibited the growth of a range of gram-positive and gram-negative microorganisms. Antimicrobial sensitivity test to 18 different types of antibiotic were evaluated using the disc diffusion method. Inhibition zone diameter was measured and calculated from the means of five determinations and expressed in terms of resistance or susceptibility. All the LAB isolates were resistant to colestin sulphate, streptomycin, amikacin, norfloxacin, nalidixic acid, mecillinam, sulphanethoxazole/ trimethoprim, kanamycin, neomycin, bacitracin and gentamycin but susceptible to erythromycin, penicillin G, chloramphenicol, tetracycline, ampicillin and nitrofurantion.

  13. Bacteriological profile and antibiotic sensitivity pattern of neonatal septicaemia in a rural tertiary care hospital in North India

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    S Thakur

    2016-01-01

    Full Text Available Background: There is not much published literature on neonatal septicemia available for the Sub-Himalayan region of North India. Hence, we undertook this study to find out the bacteriological profile and antibiotic sensitivity pattern of neonatal septicemia in the neonatal Intensive Care Unit. Material and Methods: Blood cultures were performed for all clinically suspected neonatal septicemia cases for 1-year. Identification of all pathogenic isolates was followed by antibiotic sensitivity testing. Results: We did blood cultures for 450 neonates and 42% were culture positive. Early onset sepsis were 92 (49% and 96 (51% were late onset sepsis. Gram-positive isolates were 60% and 40% were Gram-negative. Staphylococcus aureus (40%, coagulase negative Staphylococcus species (16%, non-fermenter group of organisms (NFGOs (15%, and Klebsiella pneumoniae (10% were the main isolates. Nasal cannula 101 (54%, birth asphyxia 91 (48%, and prematurity 73 (38% were the prominent risk factors associated with septicemia. Gram-positive organisms were highly resistant to penicillin (87% whereas Gram-negative isolates showed high resistance to third generation cephalosporins (53–89% and aminoglycosides (50–67%. The S. aureus isolates were methicillin-resistant in 41% whereas extended spectrum beta lactamase production was seen in 48% Gram-negative isolates.Conclusion: Our study highlights the recent emergence of Gram-positive organisms as predominant cause of neonatal septicemia in this part of Sub-Himalayan region, along with the review of literature which shows similar results from North India and rest of the world too. Though Gram-negative bacteria still remain the main cause of mortality in neonatal septicemia, we want to dispel the common notion among practitioners that they are the predominant isolates in neonatal septicemia.

  14. Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital.

    Science.gov (United States)

    Ratnumnoi, Ravee; Keorochana, Narumon; Sontisombat, Chavalit

    2017-01-01

    This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. This was a prospective cross-sectional study. A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctival and lid margin swabs were obtained from patients before they underwent cataract surgery. These swabs were used to inoculate blood agar and chocolate agar plates for culturing. After growth of the normal flora, the antibiotic sensitivity method using tobramycin, moxifloxacin, levofloxacin, and cefazolin was applied. Normal flora of conjunctiva and lid margin, along with its antibiotic sensitivity, from patients who underwent cataract surgery was assessed. A total of 120 eyes were included in this study, and bacterial isolation rates were identified. Five bacteria from the lid margin were cultured, namely, coagulase-negative staphylococcus (58.33%), Streptococcus spp. (2.5%), Corynebacterium (1.67%), Micrococcus spp. (1.67%), and Staphylococcus aureus (0.83%). Two bacteria from the conjunctiva were cultured, namely, coagulase-negative staphylococcus (30%) and Streptococcus spp. (0.83%). Results of antibiotic sensitivity test showed that all isolated bacteria are sensitive to cefazolin 100%, tobramycin 98.67%, levofloxacin 100%, and moxifloxacin 100%. Coagulase-negative staphylococci are the most common bacteria isolated from conjunctiva and lid margin.

  15. Determinants of antibiotic prescription in paediatric patients: The case of two hospitals in Maputo, Mozambique

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    L G S Monteiro

    2017-10-01

    Full Text Available Background. The need for healthcare in paediatric patients is often due to respiratory diseases, acute diarrhoea and viral fever, which suggests a limited need for the use of antibiotics. Objectives. To identify the determinants of antibiotic prescription in hospitalised paediatric patients in Mozambique. Methods. A cross-sectional study was conducted between January and June 2015. A total of 454 medical prescriptions and clinical records of children aged 0 - 14 years from Hospital Central de Maputo (HCM and Hospital Geral de Mavalane (HGM were analysed. Results. Antibiotics were used in 97.6% of the patients, with no significant differences (p>0.05 in the prescription rates of the hospitals. The most commonly used antibiotics were beta-lactams (57.3%, aminoglycosides (28.3% and co-trimoxazole (9.4%. Antibiotics were prescribed in all cases of bronchopneumonia, fever, sepsis and acute gastroenteritis. For malaria and undefined diagnoses, antibiotics were prescribed 97.8% and 99.3% of cases, respectively. It was clear that most severe clinical conditions (odds ratio (OR 9.06; 1.13 - 12.14 and age <5 years (OR 5.47;1.54 - 7.60 were treated with antibiotics. Conclusion. The prescription of antibiotics for paediatric patients at both HCM and HGM was largely influenced by patients’ clinical condition and age. It showed that physicians used an empirical approach, in the absence of laboratory tests, often leading to unnecessary antibiotic treatments with negative causative effects. Physicians should be encouraged to use an evidence-based approach for managing the cases correctly.

  16. HB&L System: rapid determination of antibiotic sensitivity of bacteria isolated from blood cultures.

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    Simone Barocci

    2010-03-01

    Full Text Available Introduction. Blood culture is an important method to detect microbial pathogens on blood, very useful for diagnosing bacterial infections. Unfortunately, classical diagnostic protocols cannot directly identify bacteria responsible for sepsis and accordingly their antimicrobial profiles. This problem causes a delay of almost two days in the availability of a specific antimicrobial profile. Objective. Among the main causes of death, sepsis have a relevant importance. For this reason it is important both to identify pathogens and to perform an antimicrobial susceptibility test in the shortest time as possible. For this purpose, the main aim of this study is the evaluation of the performances of an antimicrobial susceptibility determination directly performed on positive blood cultures. Materials and methods. This study has been performed on 70 positive blood cultures, during the period from January to July 2009. A number of 35 blood cultures were positive for Gram negative bacteria, and 35 were positive for Gram positive bacteria. From these positive blood cultures, after a short sample preparation, it has been possible to directly determine antimicrobial susceptibility profiles by using the HB&L (formerly URO-QUICK instrument. Results. The HB&L system results showed a very good correlation with both the classical disk diffusion method and VITEK 2 automatic system.The performances between the methods carried out in this study were equivalent. Conclusions. From data reported, thanks to the rapidity and simplicity of the method used, we can assert that the direct susceptibility test available with the HB&L system, is useful for a rapid and early choice of the antibiotic treatment.

  17. Diversity, distribution and quantification of antibiotic resistance genes in goat and lamb slaughterhouse surfaces and meat products.

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    Leyre Lavilla Lerma

    Full Text Available The distribution and quantification of tetracycline, sulfonamide and beta-lactam resistance genes were assessed in slaughterhouse zones throughout meat chain production and the meat products; this study represents the first to report quantitatively monitor antibiotic resistance genes (ARG in goat and lamb slaughterhouse using a culture independent approach, since most studies focused on individual bacterial species and their specific resistance types. Quantitative PCR (qPCR revealed a high prevalence of tetracycline resistance genes tetA and tetB in almost all slaughterhouse zones. Sulfonamide resistance genes were largely distributed, while beta-lactam resistance genes were less predominant. Statistical analysis revealed that resistant bacteria, in most cases, were spread by the same route in almost all slaughterhouse zones, except for tetB, blaCTX and blaTEM genes, which occurred in few zones as isolated 'hot spots.' The sum of all analyzed ARG indicated that slaughterhouse surfaces and end products act as reservoirs of ARG, mainly tet genes, which were more prevalent in slaughtering room (SR, cutting room (CR and commercial meat products (MP. Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also detected in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white room (WR zones, and also refrigerator 4 (F4 and MP were observed. Strategically controlling key zones in slaughterhouse (SR, CR and WR by adequate disinfection methods could strategically reduce the risks of ARG transmission and minimize the issues of food safety and environment contamination.

  18. Diversity, distribution and quantification of antibiotic resistance genes in goat and lamb slaughterhouse surfaces and meat products.

    Science.gov (United States)

    Lavilla Lerma, Leyre; Benomar, Nabil; Knapp, Charles W; Correa Galeote, David; Gálvez, Antonio; Abriouel, Hikmate

    2014-01-01

    The distribution and quantification of tetracycline, sulfonamide and beta-lactam resistance genes were assessed in slaughterhouse zones throughout meat chain production and the meat products; this study represents the first to report quantitatively monitor antibiotic resistance genes (ARG) in goat and lamb slaughterhouse using a culture independent approach, since most studies focused on individual bacterial species and their specific resistance types. Quantitative PCR (qPCR) revealed a high prevalence of tetracycline resistance genes tetA and tetB in almost all slaughterhouse zones. Sulfonamide resistance genes were largely distributed, while beta-lactam resistance genes were less predominant. Statistical analysis revealed that resistant bacteria, in most cases, were spread by the same route in almost all slaughterhouse zones, except for tetB, blaCTX and blaTEM genes, which occurred in few zones as isolated 'hot spots.' The sum of all analyzed ARG indicated that slaughterhouse surfaces and end products act as reservoirs of ARG, mainly tet genes, which were more prevalent in slaughtering room (SR), cutting room (CR) and commercial meat products (MP). Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also detected in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white room (WR) zones, and also refrigerator 4 (F4) and MP were observed. Strategically controlling key zones in slaughterhouse (SR, CR and WR) by adequate disinfection methods could strategically reduce the risks of ARG transmission and minimize the issues of food safety and environment contamination.

  19. Feasibility study of veterinary antibiotic consumption in Germany--comparison of ADDs and UDDs by animal production type, antimicrobial class and indication.

    Science.gov (United States)

    Merle, Roswitha; Robanus, Matthias; Hegger-Gravenhorst, Christine; Mollenhauer, Yvonne; Hajek, Peter; Käsbohrer, Annemarie; Honscha, Walther; Kreienbrock, Lothar

    2014-01-08

    Within a feasibility study the use of antibiotics in pigs and cattle was determined in 24 veterinary practices in Lower Saxony and on 66 farms in North Rhine-Westphalia in Germany. Focus was laid on the comparison of the Used Daily Doses (UDD) (dose per animal and day prescribed by the veterinarians) with the Defined Animal Daily Doses (ADD) (dose per animal and day calculated by means of recommended dosages and estimated live weights). For piglets and calves most of the UDD (50% and 46% of nUDD, respectively) were above the ADD (i.e. UDD/ADD-ratio above 1.25). Regarding sows, fattening pigs, dairy and beef cattle, most of the UDDs (49% to 65% of nUDD) were lower than the respective ADD (i.e. UDD/ADD-ratio below 0.8). In pigs, the UDDs of beta-lactams, fluoroquinolones and cephalosporins, and in cattle, those of macrolides and beta-lactams were often below the ADDs. Tetracyclines were frequently used above the recommended dose.Enteric diseases were more often treated below the recommended dose than respiratory diseases, possibly due to overestimation of the live weight (diarrhea in young animals, respiratory diseases in elder animals) and consequently overestimation of the recommended dose. Comparisons between UDD and ADD can be used to observe differences between antimicrobials and trends in the usage of antibiotics. But individual treatment comparisons of UDD and ADD must be interpreted carefully, because they may be due to lower live weights than estimated. Correlating such data with data on the occurrence of resistant bacteria in future may help to improve resistance prevention and control.

  20. Phage type and sensitivity to antibiotics of Staphylococcus aureus film-forming strains isolated from airway mucosa

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    O. S. Voronkova

    2014-10-01

    Full Text Available Today film-forming strains of bacteria play very important role in clinical pathology. Staphylococci are ones of most dangerous of them. This bacteria can determine different pathological processes, for example, complication of airway mucosa. The ability to form a biofilm is one of the main properties of nosocomial strains. These strains should be monitored and their carriers are to be properly treated. To determine the origin of staphylococci strains we used bacteriophages from the International kit. The aim of research was to determine the phage type of staphylococci film-forming strains, that were isolated from naso-pharingial mucosa. Phage typing has been carried out for 16 film-forming strains of S. aureus. To solve this problem, we used the International phage kit by Fisher’s method. As a result, sensitivity to phages from the International kit showed 53.8% of studied strains of S. aureus. 64.3% of sensitivity strains were lysed by one of the phage, 21.4% – were by two of the phages, 14.3% – by three of the phages. Isolates were sensitive to phages: 81 – 42.9%, 75 – 35.7%, 28.6% were sensitive to phages 47 and 53. All cases of detection of sensitivity to phage 47 coincided with the ability to form biofilm. Among non-film-forming strains there was no sensitive strains for this phage. Film-forming strains resist to erythromycin (62.5%, ciprofloxacin (43.8%, gentamicin (56.3%, tetracycline (87.5%, amoxicillin (93.8%, and cefuroxime (37.5%. All cases of sensitivity to phage 47 coincided with resistance to erythromycin, amoxicillin and tetracycline. For two of these strains, we also defined resistance to gentamicin and for one of them – to ciprofloxacin. Results of research allowed to relate the bacterial cultures for determining the type. This may have implications for studying of film-forming ability, because surface structures of bacterial cell take place in this process. Belonging of an isolate to specific phage type may

  1. Characterization and antimicrobial susceptibility of one antibiotic-sensitive and one multidrug-resistant Corynebacterium kroppenstedtii strain isolated from patients with granulomatous mastitis

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    I. Fernández-Natal

    2016-11-01

    Full Text Available Human infections associated with Corynebacterium kroppenstedtii are rarely reported, and this organism is usually described as antibiotic sensitive. Almost all published cases of C. kroppenstedtii infections have been associated with breast pathology in women and have been described in New Zealand, France, Canada, India and Japan. Here we describe the microbiologic characteristics of two strains isolated from two women diagnosed of granulomatous mastitis in Spain. One C. kroppenstedtii isolate was antibiotic sensitive while the other was multidrug resistant. Biochemical identification was possible using a wide battery of methods including API Coryne V2.0, API Strep, API NH, API NE, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA gene amplification and sequencing. Antimicrobial susceptibility to 28 antibiotics as determined by Etest showed one isolate being sensitive to benzylpenicillin, ciprofloxacin, moxifloxacin, gentamicin, vancomycin, clindamycin, tetracycline, linezolid and rifampin. The second isolate showed resistance to ciprofloxacin, moxifloxacin, clindamycin, tetracycline and rifampin. The multidrug-resistant isolate contained the erm(X, tet(W, cmx, aphA1-IAB, strAB and sul1 resistance genes known from the R plasmid pJA144188 of Corynebacterium resistens. These genes were absent in the genome of the antibiotic-sensitive isolate. This report confirms the tropism of this microorganism for women's breasts and presents the first description of a multidrug-resistant C. kroppenstedtii strain.

  2. Novel quorum-quenching agents promote methicillin-resistant Staphylococcus aureus (MRSA) wound healing and sensitize MRSA to β-lactam antibiotics.

    Science.gov (United States)

    Kuo, David; Yu, Guanping; Hoch, Wyatt; Gabay, Dean; Long, Lisa; Ghannoum, Mahmoud; Nagy, Nancy; Harding, Clifford V; Viswanathan, Rajesh; Shoham, Menachem

    2015-03-01

    The dwindling repertoire of antibiotics to treat methicillin-resistant Staphylococcus aureus (MRSA) calls for novel treatment options. Quorum-quenching agents offer an alternative or an adjuvant to antibiotic therapy. Three biaryl hydroxyketone compounds discovered previously (F1, F12, and F19; G. Yu, D. Kuo, M. Shoham, and R. Viswanathan, ACS Comb Sci 16:85-91, 2014) were tested for efficacy in MRSA-infected animal models. Topical therapy of compounds F1 and F12 in a MRSA murine wound infection model promotes wound healing compared to the untreated control. Compounds F1, F12, and F19 afford significant survival benefits in a MRSA insect larva model. Combination therapy of these quorum-quenching agents with cephalothin or nafcillin, antibiotics to which MRSA is resistant in monotherapy, revealed additional survival benefits. The quorum-quenching agents sensitize MRSA to the antibiotic by a synergistic mode of action that also is observed in vitro. An adjuvant of 1 μg/ml F1, F12, or F19 reduces the MIC of nafcillin and cephalothin about 50-fold to values comparable to those for vancomycin, the antibiotic often prescribed for MRSA infections. These findings suggest that it is possible to resurrect obsolete antibiotic therapies in combination with these novel quorum-quenching agents. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. In vitro activity of XF-73, a novel antibacterial agent, against antibiotic-sensitive and -resistant Gram-positive and Gram-negative bacterial species.

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    Farrell, David J; Robbins, Marion; Rhys-Williams, William; Love, William G

    2010-06-01

    The antibacterial activity of XF-73, a dicationic porphyrin drug, was investigated against a range of Gram-positive and Gram-negative bacteria with known antibiotic resistance profiles, including resistance to cell wall synthesis, protein synthesis, and DNA and RNA synthesis inhibitors as well as cell membrane-active antibiotics. Antibiotic-sensitive strains for each of the bacterial species tested were also included for comparison purposes. XF-73 was active [minimum inhibitory concentration (MIC) 0.25-4 mg/L] against all of the Gram-positive bacteria tested, irrespective of the antibiotic resistance profile of the isolates, suggesting that the mechanism of action of XF-73 is unique compared with the major antibiotic classes. Gram-negative activity was lower (MIC 1 mg/L to > 64 mg/L). Minimum bactericidal concentration data confirmed that the activity of XF-73 was bactericidal. Time-kill kinetics against healthcare-associated and community-associated meticillin-resistant Staphylococcus aureus isolates demonstrated that XF-73 was rapidly bactericidal, with > 5 log(10) kill obtained after 15 min at 2 x MIC, the earliest time point sampled. The post-antibiotic effect (PAE) for XF-73 under conditions where the PAE for vancomycin was 5.4 h. XF-73 represents a novel broad-spectrum Gram-positive antibacterial drug with potentially beneficial characteristics for the treatment and prevention of Gram-positive bacterial infections. 2010. Published by Elsevier B.V.

  4. [Cefazolin efficacy and antibiotic sensitivity against pathogenic bacteria in pediatric with acute upper urinary tract infection].

    Science.gov (United States)

    Fuke, Toshiya; Abe, Yoshifusa; Hoshino, Akihiro; Oto, Hideyasu; Sakai, Naho; Murayama, Junichiro; Yoshida, Koichiro; Itabashi, Kazuo

    2010-05-01

    Acute upper urinary tract infection may cause sepsis, especially in neonates and infants, mandating the choice of appropriate, effective antibacterials minimizing increasing bacterial resistance. Frequently prescribing broad-spectrum cephalosporinin is one such example. Different antibacterial therapies are initiated clinically due to treatment protocol differences among institutions, disease severity, etc. We studied the efficacy of cefazolin (CEZ), a first-generation cephalosporin, as first-line parenteral treatment in acute upper urinary tract infection. We found that 88.9% of microbial infections have indications for CEZ. CEZ efficacy is 91.3%, and 97.2% of urine cultures show negative results. Escherichia coli sensitivity to antibacterial agents is 90.9% of the minimal inhibitory concentration (MIC) pediatric therapy in acute upper urinary tract infection.

  5. Next step in antibiotic stewardship: Pharmacist-provided penicillin allergy testing.

    Science.gov (United States)

    Gugkaeva, Z; Crago, J S; Yasnogorodsky, M

    2017-08-01

    Penicillin allergy limits therapeutic options for patients but often disappears over time, leaving patients erroneously labelled allergic and leading to the utilization of broad-spectrum and more expensive antibiotics. Penicillin allergy can be effectively assessed via skin testing. To improve patient access to penicillin allergy testing by implementing a pharmacist-provided service in a hospital setting. Beta-lactams remain a mainstream therapy for many infections due to their effectiveness, low side effects and affordability. Typically, patient access to penicillin allergy testing is limited by the availability of allergy specialists, who traditionally perform such testing. A pharmacist-provided penicillin allergy testing service was implemented at our hospital in 2015 and became a powerful antibiotic stewardship tool. Removing penicillin allergy from patient profiles significantly expanded therapeutic options, expedited discharges and reduced costs of care. Pharmacists can expand patient access to penicillin allergy testing. Pharmacist-provided penicillin allergy testing permitted optimized antibiotic treatment and expedited discharges. © 2017 John Wiley & Sons Ltd.

  6. Temporal relationship between antibiotic use and respiratory virus activities in the Republic of Korea: a time-series analysis.

    Science.gov (United States)

    Ryu, Sukhyun; Kim, Sojung; Kim, Bryan I; Klein, Eili Y; Yoon, Young Kyung; Chun, Byung Chul

    2018-01-01

    Inappropriate use of antibiotics increases resistance and reduces their effectiveness. Despite evidence-based guidelines, antibiotics are still commonly used to treat infections likely caused by respiratory viruses. In this study, we examined the temporal relationships between antibiotic usage and respiratory infections in the Republic of Korea. The number of monthly antibiotic prescriptions and the incidence of acute respiratory tract infections between 2010 and 2015 at all primary care clinics were obtained from the Korean Health Insurance Review and Assessment Service. The monthly detection rates of respiratory viruses, including adenovirus, respiratory syncytial virus, influenza virus, human coronavirus, and human rhinovirus, were collected from Korea Centers for Disease Control and Prevention. Cross-correlation analysis was conducted to quantify the temporal relationship between antibiotic use and respiratory virus activities as well as respiratory infections in primary clinics. The monthly use of different classes of antibiotic, including penicillins, other beta-lactam antibacterials, macrolides and quinolones, was significantly correlated with influenza virus activity. These correlations peaked at the 0-month lag with cross-correlation coefficients of 0.45 ( p  < 0.01), 0.46 ( p  < 0.01), 0.40 ( p  < 0.01), and 0.35 (< 0.01), respectively. Furthermore, a significant correlation was found between acute bronchitis and antibiotics, including penicillin (0.73, p  < 0.01), macrolides (0.74, p  < 0.01), and quinolones (0.45, p  < 0.01), at the 0-month lag. Our findings suggest that there is a significant temporal relationship between influenza virus activity and antibiotic use in primary clinics. This relationship indicates that interventions aimed at reducing influenza cases in addition to effort to discourage the prescription of antibiotics by physicians may help to decrease unnecessary antibiotic consumption.

  7. Significant reduction of antibiotic use in the community after a nationwide campaign in France, 2002-2007.

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    Elifsu Sabuncu

    2009-06-01

    Full Text Available BACKGROUND: Overuse of antibiotics is the main force driving the emergence and dissemination of bacterial resistance in the community. France consumes more antibiotics and has the highest rate of beta-lactam resistance in Streptococcus pneumoniae than any other European country. In 2001, the government initiated "Keep Antibiotics Working"; the program's main component was a campaign entitled "Les antibiotiques c'est pas automatique" ("Antibiotics are not automatic" launched in 2002. We report the evaluation of this campaign by analyzing the evolution of outpatient antibiotic use in France 2000-2007, according to therapeutic class and geographic and age-group patterns. METHODS AND FINDINGS: This evaluation is based on 2000-2007 data, including 453,407,458 individual reimbursement data records and incidence of flu-like syndromes (FLSs. Data were obtained from the computerized French National Health Insurance database and provided by the French Sentinel Network. As compared to the preintervention period (2000-2002, the total number of antibiotic prescriptions per 100 inhabitants, adjusted for FLS frequency during the winter season, changed by -26.5% (95% confidence interval [CI] -33.5% to -19.6% over 5 years. The decline occurred in all 22 regions of France and affected all antibiotic therapeutic classes except quinolones. The greatest decrease, -35.8% (95% CI -48.3% to -23.2%, was observed among young children aged 6-15 years. A significant change of -45% in the relationship between the incidence of flu-like syndromes and antibiotic prescriptions was observed. CONCLUSIONS: The French national campaign was associated with a marked reduction of unnecessary antibiotic prescriptions, particularly in children. This study provides a useful method for assessing public-health strategies designed to reduce antibiotic use.

  8. Industrial enzymatic production of cephalosporin-based beta-lactams.

    Science.gov (United States)

    Barber, Michael S; Giesecke, Ulrich; Reichert, Arno; Minas, Wolfgang

    2004-01-01

    Cephalosporins are chemically closely related to penicillins both work by inhibiting the cell wall synthesis of bacteria. The first generation cephalosporins entered the market in 1964. Second and third generation cephalosporins were subsequently developed that were more powerful than the original products. Fourth generation cephalosporins are now reaching the market. Each newer generation of cephalosporins has greater Gram-negative antimicrobial properties than the preceding generation. Conversely, the 'older' generations of cephalosporins have greater Gram-positive (Staphylococcus and Streptococcus) coverage than the 'newer' generations. Frequency of dosing decreases and palatability generally improve with increasing generations. The advent of fourth generation cephalosporins with the launch of cefepime extended the spectrum against Gram-positive organisms without a significant loss of activity towards Gram-negative bacteria. Its greater stability to beta-lactamases increases its efficacy against drug-resistant bacteria. In this review we present the current situation of this mature market. In addition, we present the current state of the technologies employed for the production of cephalosporins, focusing on the new and environmentally safer 'green' routes to the products. Starting with the fermentation and purification of CPC, enzymatic conversion in conjunction with aqueous chemistry will lead to some key intermediates such as 7-ACA, TDA and TTA, which then can be converted into the active pharmaceutical ingredient (API), again applying biocatalytic technologies and aqueous chemistry. Examples for the costing of selected products are provided as well.

  9. Surveillance of multidrug resistant suppurative infection causing bacteria in hospitalized patients in an Indian tertiary care hospital

    OpenAIRE

    Nabakishore Nayak; Rajesh K. Lenka; Rabindra N. Padhy

    2014-01-01

    Objective: To examine antibiograms of a cohort of suppurative bacteria isolated from wound-swabs from hospitalized patients of all economic groups of a typical Indian teaching hospital. Methods: In surveillance, antibiotic resistance patterns of 10 species of suppurative bacteria isolated from wound-swabs over a period of 24 months were recorded. Those were subjected to antibiotic sensitivity test, using 16 prescribed antibiotics of 5 different groups (3 aminoglycosides, 4 beta-lactams, 3 ...

  10. A Signal-On Fluorosensor Based on Quench-Release Principle for Sensitive Detection of Antibiotic Rapamycin

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    Hee-Jin Jeong

    2015-03-01

    Full Text Available An antibiotic rapamycin is one of the most commonly used immunosuppressive drugs, and also implicated for its anti-cancer activity. Hence, the determination of its blood level after organ transplantation or tumor treatment is of great concern in medicine. Although there are several rapamycin detection methods, many of them have limited sensitivity, and/or need complicated procedures and long assay time. As a novel fluorescent biosensor for rapamycin, here we propose “Q’-body”, which works on the fluorescence quench-release principle inspired by the antibody-based quenchbody (Q-body technology. We constructed rapamycin Q’-bodies by linking the two interacting domains FKBP12 and FRB, whose association is triggered by rapamycin. The fusion proteins were each incorporated position-specifically with one of fluorescence dyes ATTO520, tetramethylrhodamine, or ATTO590 using a cell-free translation system. As a result, rapid rapamycin dose-dependent fluorescence increase derived of Q’-bodies was observed, especially for those with ATTO520 with a lowest detection limit of 0.65 nM, which indicates its utility as a novel fluorescent biosensor for rapamycin.

  11. A signal-on fluorosensor based on quench-release principle for sensitive detection of antibiotic rapamycin.

    Science.gov (United States)

    Jeong, Hee-Jin; Itayama, Shuya; Ueda, Hiroshi

    2015-03-26

    An antibiotic rapamycin is one of the most commonly used immunosuppressive drugs, and also implicated for its anti-cancer activity. Hence, the determination of its blood level after organ transplantation or tumor treatment is of great concern in medicine. Although there are several rapamycin detection methods, many of them have limited sensitivity, and/or need complicated procedures and long assay time. As a novel fluorescent biosensor for rapamycin, here we propose "Q'-body", which works on the fluorescence quench-release principle inspired by the antibody-based quenchbody (Q-body) technology. We constructed rapamycin Q'-bodies by linking the two interacting domains FKBP12 and FRB, whose association is triggered by rapamycin. The fusion proteins were each incorporated position-specifically with one of fluorescence dyes ATTO520, tetramethylrhodamine, or ATTO590 using a cell-free translation system. As a result, rapid rapamycin dose-dependent fluorescence increase derived of Q'-bodies was observed, especially for those with ATTO520 with a lowest detection limit of 0.65 nM, which indicates its utility as a novel fluorescent biosensor for rapamycin.

  12. Distinct effects of struvite and biochar amendment on the class 1 integron antibiotic resistance gene cassettes in phyllosphere and rhizosphere.

    Science.gov (United States)

    An, Xin-Li; Chen, Qing-Lin; Zhu, Dong; Su, Jian-Qiang

    2018-08-01

    Struvite recovered from wastewater is promising for recycling phosphorus into soil as fertilizers. However, struvite application may prompt the proliferation of antibiotic resistance in soil and plant. This study examined the impacts of struvite application and biochar amendment on integrons abundance and gene cassette contexts in rhizosphere soil and phyllosphere using quantitative PCR and clone library analysis. Microcosm experiments revealed that class 1 integron was the most prevalent in all samples, with higher concentration and higher relative abundance in rhizosphere than those in phyllosphere. The majority of resistance gene cassettes were associated with genes encoding resistance to aminoglycosides, beta-lactams and chloramphenicols. Struvite application significantly increased the genetic diversity of antibiotic resistance gene cassettes in both rhizosphere and phyllosphere. However, biochar amendment attenuated the increasing effect of struvite application exerting on the class 1 integron antibiotic resistance gene cassette pool in phyllosphere. These findings highlighted human activities to be the source of integron gene cassette pool and raised the possibility of using biochar amendment as an alternative mean for mitigating antibiotic resistance in environments. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Molecular determination of extended spectrum b-lactamases antibiotics resistance genes in E.coli isolated from diarrhea in cattle

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    Ghassan Khudhair Ismaeel

    2017-07-01

    Full Text Available None response to the treatment by an antibiotic called antibiotics resistance result from some genes called resistance genes .This mechanism is widespread in most of the bacteria, like E.coli . All of the extended resistance genes called (ESBIS is a typical example for study of some genes that resistance beta-lactam antibiotic is subject of this research. Fifty feces sample were collected from cattle suffering from diarrhea in alqaissiyah city were cultured on selective media for E.coli , then DNA was extracted from all E.coli isolates for antibiotic resistance gene detection by PCR ; The results of this study revealed the prevalence of B-lactamase gene four B-lactamases genes in E.coli blaAmpc gene were (91.4%, the blactx-m gene were (80%, blaTem were (62.8% and finally and blaSHV gene were (22% among isolates E.coli ; blaAMPC gene has high prevalence than others genes while blaSHV was a lower percentage than other genes

  14. Antibacterial activity of exogenous glutathione and its synergism on antibiotics sensitize carbapenem-associated multidrug resistant clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Alharbe, Roaa; Almansour, Ayidh; Kwon, Dong H

    2017-10-01

    A major clinical impact of A. baumannii is hospital-acquired infections including ventilator-associated pneumonia. The treatment of this pathogen is often difficult due to its innate and acquired resistance to almost all commercially available antibiotics. Infections with carbapenem-associated multidrug resistant A. baumannii is the most problematic. Glutathione is a tripeptide thiol-antioxidant and antibacterial activity of exogenous glutathione was reported in some bacteria. However, clinical relevance and molecular details of the antibacterial activity of glutathione are currently unclear. Seventy clinical isolates of A. baumannii including 63 carbapenem-associated multidrug resistant isolates and a type strain A. baumannii ATCC 19606 were used to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Fractional inhibitory concentration (FIC) and time-killing activity with meropenem and/or glutathione were also determined in the carbapenem-associated multidrug resistant isolates. In addition, the roles of exogenous glutathione in multidrug efflux pumps and β-lactamase production were examined. Levels of MIC and MBC were ranged from 10 to 15mM of exogenous glutathione. All tested carbapenem-associated multidrug resistant isolates were sensitized by all tested antibiotics in combination with subinhibitory concentrations of glutathione. FIC levels of glutathione with carbapenem (meropenem) were allcarbapenem-associated multidrug resistant isolates were killed by subinhibitory concentrations of both glutathione and meropenem at>2log10 within 12h, suggesting glutathione synergistically interacts with meropenem. The roles of multidrug efflux pumps and β-lactamase production were excluded for the glutathione-mediated antibiotic susceptibility. Overall results demonstrate that the antibacterial activity of glutathione is clinically relevant and its synergism on antibiotics sensitizes clinical isolates of A. baumannii regardless

  15. Strategies for the screening of antibiotic residues in eggs: comparison of the validation of the classical microbiological method with an immunobiosensor method.

    Science.gov (United States)

    Gaudin, Valérie; Rault, Annie; Hedou, Celine; Soumet, Christophe; Verdon, Eric

    2017-09-01

    Efficient screening methods are needed to control antibiotic residues in eggs. A microbiological kit (Explorer® 2.0 test (Zeu Inmunotech, Spain)) and an immunobiosensor kit (Microarray II (AM® II) on Evidence Investigator™ system (Randox, UK)) have been evaluated and validated for screening of antibiotic residues in eggs, according to the European decision EC/2002/657 and to the European guideline for the validation of screening methods. The e-reader™ system, a new automatic incubator/reading system, was coupled to the Explorer 2.0 test. The AM II kit can detect residues of six different families of antibiotics in different matrices including eggs. For both tests, a different liquid/liquid extraction of eggs had to be developed. Specificities of the Explorer 2.0 and AM II kit were equal to 8% and 0% respectively. The detection capabilities were determined for 19 antibiotics, with representatives from different families, for Explorer 2.0 and 12 antibiotics for the AM II kit. For the nine antibiotics having a maximum residue limit (MRL) in eggs, the detection capabilities CCβ of Explorer 2.0 were below the MRL for four antibiotics, equal to the MRL for two antibiotics and between 1 and 1.5 MRLs for the three remaining antibiotics (tetracyclines). For the antibiotics from other families, the detection capabilities were low for beta-lactams and sulfonamides and satisfactory for dihydrostreptomycin (DHS) and fluoroquinolones, which are usually difficult to detect with microbiological tests. The CCβ values of the AM II kit were much lower than the respective MRLs for three detected antibiotics (tetracycline, oxytetracycline, tylosin). Concerning the nine other antibiotics, the detection capabilities determined were low. The highest CCβ was obtained for streptomycin (100 µg kg -1 ).

  16. Persistence of antibiotic-resistant and -sensitive Proteus mirabilis strains in the digestive tract of the housefly (Musca domestica) and green bottle flies (Calliphoridae).

    Science.gov (United States)

    Wei, Ting; Miyanaga, Kazuhiko; Tanji, Yasunori

    2014-10-01

    Synanthropic flies have been implicated in the rapid dissemination of antibiotic-resistant bacteria and resistance determinants in the biosphere. These flies stably harbor a considerable number of bacteria that exhibit resistance to various antibiotics, but the mechanisms underlying this phenomenon remain unclear. In this study, we investigated the persistence of antibiotic-resistant bacteria in the digestive tract of houseflies and green bottle flies, using Proteus mirabilis as a model microorganism. One resistant strain carried the blaTEM and aphA1 genes, and another carried a plasmid containing qnrD gene. Quantitative PCR and 454 pyrosequencing were used to monitor the relative abundance of the Proteus strains, as well as potential changes in the overall structure of the whole bacterial community incurred by the artificial induction of Proteus cultures. Both antibiotic-resistant and -sensitive P. mirabilis strains persisted in the fly digestive tract for at least 3 days, and there was no significant difference in the relative abundance of resistant and sensitive strains despite the lower growth rate of resistant strains when cultured in vitro. Therefore, conditions in the fly digestive tract may allow resistant strains to survive the competition with sensitive strains in the absence of antibiotic selective pressure. The composition of the fly-associated bacterial community changed over time, but the contribution of the artificially introduced P. mirabilis strains to these changes was not clear. In order to explain these changes, it will be necessary to obtain more information about bacterial interspecies antagonism in the fly digestive tract.

  17. Influence of regular reporting on local Pseudomonas aeruginosa and Acinetobacter spp. sensitivity to antibiotics on consumption of antibiotics and resistance patterns.

    Science.gov (United States)

    Djordjevic, Z M; Folic, M M; Jankovic, S M

    2017-10-01

    Regular surveillance of antimicrobial resistance is an important component of multifaceted interventions directed at the problem with resistance of bacteria causing healthcare-associated infections (HAIs) in intensive care units (ICUs). Our aim was to analyse antimicrobial consumption and resistance among isolates of Pseudomonas aeruginosa and Acinetobacter spp. causing HAIs, before and after the introduction of mandatory reporting of resistance patterns to prescribers. A retrospective observational study was conducted between January 2011 and December 2015, at an interdisciplinary ICU of the Clinical Centre Kragujevac, Serbia. The intervention consisted of continuous resistance monitoring of all bacterial isolates from ICU patients and biannual reporting of results per isolate to prescribers across the hospital. Both utilization of antibiotics and density of resistant isolates of P. aeruginosa and Acinetobacter spp. were followed within the ICU. Resistance densities of P. aeruginosa to all tested antimicrobials were lower in 2015, in comparison with 2011. Although isolates of Acinetobacter spp. had lower resistance density in 2015 than in 2011 to the majority of investigated antibiotics, a statistically significant decrease was noted only for piperacillin/tazobactam. Statistically significant decreasing trends of consumption were recorded for third-generation cephalosporins, aminoglycosides and fluoroquinolones, whereas for the piperacillin/tazobactam, ampicillin/sulbactam and carbapenems, utilization trends were decreasing, but without statistical significance. In the same period, increasing trends of consumption were observed for tigecycline and colistin. Regular monitoring of resistance of bacterial isolates in ICUs and reporting of summary results to prescribers may lead to a significant decrease in utilization of some antibiotics and slow restoration of P. aeruginosa and Acinetobacter spp. susceptibility. © 2017 John Wiley & Sons Ltd.

  18. Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital

    OpenAIRE

    Ratnumnoi,Ravee; Keorochana,Narumon; Sonthisombat,Chavalit

    2017-01-01

    Ravee Ratnumnoi, Narumon Keorochana, Chavalit Sontisombat Department of Ophthalmology, Phramongkutklao Hospital, Bangkok, Thailand Objective: This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. Design: This was a prospective cross-sectional study. Patients and methods: A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctiva...

  19. Antibacterial activity of epigallocatechin-3-gallate (EGCG) and its synergism with β-lactam antibiotics sensitizing carbapenem-associated multidrug resistant clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Lee, Spencer; Razqan, Ghaida Saleh Al; Kwon, Dong H

    2017-01-15

    Infections caused by Acinetobacter baumannii were responsive to conventional antibiotic therapy. However, recently, carbapenem-associated multidrug resistant isolates have been reported worldwide and present a major therapeutic challenge. Epigallocatechin-3-Gallate (EGCG) extracted from green tea exhibits antibacterial activity. We evaluated the antibacterial activity of EGCG and possible synergism with antibiotics in carbapenem-associated multidrug resistant A. baumannii. A potential mechanism for synergism was also explored. Seventy clinical isolates of A. baumannii collected from geographically different areas were analyzed by minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EGCG. Checkerboard and time-killing assays were performed to exam the synergism between EGCG and antibiotics. The effects of EGCG on a multidrug efflux pump inhibitor (1-[1-naphthylmethyl] piperazine; NMP) and β-lactamase production were also examined in A. baumannii. Sixty-three of 70 clinical isolates of A. baumannii carried carbapenemase-encoding genes with carbapenem-associated multidrug resistance. Levels of MIC and MBC of EGCG ranged from 64 to 512µg/ml and from 128 to ≥1024µg/ml, respectively among the clinical isolates. MIC 90 and MBC 86 levels were 256µg/ml and 512µg/ml of EGCG, respectively. Subinhibitory concentration of EGCG in combination with all antibiotics tested, including carbapenem, sensitized (MICs fall≤1.0µg/ml) all carbapenem-associated multidrug resistant isolates. Checkerboard and time-killing assays showed synergism between EGCG and meropenem (or carbenicillin) counted as fractional inhibitory concentration of 2log10 within 12h, respectively. EGCG significantly increased the effect of NMP but was unrelated to β-lactamase production in A. baumannii, suggesting EGCG may be associated with inhibition of efflux pumps. Overall we suggest that EGCG-antibiotic combinations might provide an alternative approach to treat

  20. [Utilization of antibiotics according to most frequent indications at Hungarian hospitals and results of surveys].

    Science.gov (United States)

    Ternák, G; Almási, I

    1997-05-25

    Antibiotic utilisation of 8 Hungarian hospitals was analyzed examining the case histories of patients who were discharged between January 1 and 31, 1995. Usage of antibiotics in the most frequent indications is reported in this paper. Majority of the prescriptions for the treatment of upper and lower respiratory tract infections were broad spectrum beta lactams. Higher rate of penicillin usage was found only in tonsillitis cases. Besides II. generation cephalosporins (22.7% of 730 prescriptions), beta-lactamase inhibitor + aminopenicillin combinations (13.4%) and III. generation cephalosporins (9.5%) considerable quantity of aminoglycosides (14.9%) and quinolones (9.5%) were found in pneumonia. Relatively high rate of aminoglycosides in the treatment of lower respiratory infections is inconsistent with therapeutic guidelines in force. Co-trimoxazol and quinolones were most frequently prescribed for the treatment of lower urinary tract infections. Traditional urodesinficients were on the first place only at one hospital. Treatment of frequently occurring nosocomial infections was compared with those of community acquired at the same site. There was not significant difference in the utilisation rates of the most of antibiotic groups regarding place of disease acquisition. 44% of the 1373 prescriptions for perioperative profilaxis was indicated for clean operations where benefit of antibiotic administration is questionable. Duration of antibiotic profilaxis was more than 48 hours in 59% of prescriptions. Drugs most frequently used for perioperative profilaxis were II. generation cephalosporins (23.7%), metronidazol (16.7%), aminoglycosides (9.6%) and III. generation cephalosporines (9.6%). The authors compare their results to the literature. They suggest the setting up of "infection control committees" to organise the antibiotic policies in hospitals.

  1. Residence of Streptococcus pneumoniae and Moraxella catarrhalis within polymicrobial biofilm promotes antibiotic resistance and bacterial persistence in vivo.

    Science.gov (United States)

    Perez, Antonia C; Pang, Bing; King, Lauren B; Tan, Li; Murrah, Kyle A; Reimche, Jennifer L; Wren, John T; Richardson, Stephen H; Ghandi, Uma; Swords, W Edward

    2014-04-01

    Otitis media (OM) is an extremely common pediatric ailment caused by opportunists that reside within the nasopharynx. Inflammation within the upper airway can promote ascension of these opportunists into the middle ear chamber. OM can be chronic/recurrent in nature, and a wealth of data indicates that in these cases, the bacteria persist within biofilms. Epidemiological data demonstrate that most cases of OM are polymicrobial, which may have significant impact on antibiotic resistance. In this study, we used in vitro biofilm assays and rodent infection models to examine the impact of polymicrobial infection with Moraxella catarrhalis and Streptococcus pneumoniae (pneumococcus) on biofilm resistance to antibiotic treatment and persistence in vivo. Consistent with prior work, M. catarrhalis conferred beta-lactamase-dependent passive protection from beta-lactam killing to pneumococci within polymicrobial biofilms. Moreover, pneumococci increased resistance of M. catarrhalis to macrolide killing in polymicrobial biofilms. However, pneumococci increased colonization in vivo by M. catarrhalis in a quorum signal-dependent manner. We also found that co-infection with M. catarrhalis affects middle ear ascension of pneumococci in both mice and chinchillas. Therefore, we conclude that residence of M. catarrhalis and pneumococci within the same biofilm community significantly impacts resistance to antibiotic treatment and bacterial persistence in vivo. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  2. NOVEL ANTIBIOTIC RESISTANCE DETERMINANTS FROM AGRICULTURAL SOIL EXPOSED TO ANTIBIOTICS WIDELY USED IN HUMAN MEDICINE AND ANIMAL FARMING.

    Science.gov (United States)

    Lau, Calvin Ho-Fung; van Engelen, Kalene; Gordon, Stephen; Renaud, Justin; Topp, Edward

    2017-06-16

    Antibiotic resistance has emerged globally as one of the biggest threats to human and animal health. Although the excessive use of antibiotics is recognized for accelerating the selection for resistance, there is a growing body of evidence suggesting that natural environments are "hotspots" for the development of both ancient and contemporary resistance mechanisms. Given that pharmaceuticals can be entrained onto agricultural land through anthropogenic activities, this could be a potential driver for the emergence and dissemination of resistance in soil bacteria. Using functional metagenomics, we interrogated the "resistome" of bacterial communities found in a collection of Canadian agricultural soil, some of which had been receiving antibiotics widely used in human medicine (macrolides) or food animal production (sulfamethazine, chlortetracycline and tylosin) for up to 16 years. Of the 34 new antibiotic resistance genes (ARGs) recovered, the majority were predicted to encode for (multi)drug efflux systems, while a few share little to no homology with established resistance determinants. We characterized several novel gene products, including putative enzymes that can confer high-level resistance against aminoglycosides, sulfonamides, and broad range of beta-lactams, with respect to their resistance mechanisms and clinical significance. By coupling high-resolution proteomics analysis with functional metagenomics, we discovered an unusual peptide, PPP AZI 4 , encoded within an alternative open-reading frame not predicted by bioinformatics tools. Expression of the proline-rich PPP AZI 4 can promote resistance against different macrolides but not other ribosomal-targeting antibiotics, implicating a new macrolide-specific resistance mechanism that could be fundamentally linked to the evolutionary design of this peptide. IMPORTANCE Antibiotic resistance is a clinical phenomenon with an evolutionary link to the microbial pangenome. Genes and protogenes encoding for

  3. Rapid and sensitive determination of nine bisphenol analogues, three amphenicol antibiotics, and six phthalate metabolites in human urine samples using UHPLC-MS/MS.

    Science.gov (United States)

    Yao, Yuan; Shao, Yijun; Zhan, Ming; Zou, Xiaoli; Qu, Weidong; Zhou, Ying

    2018-06-01

    Bisphenol analogues, amphenicol antibiotics, and phthalate have widely aroused public concerns due to their adverse effects on human health. In this study, a rapid and sensitive method for determination of nine bisphenol analogues, three amphenicol antibiotics, and six phthalate metabolites in the urine based on ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry was developed and validated. The sample pretreatment condition on the base of mixed-mode anion-exchange (Oasis MAX) SPE was optimized to separate bisphenol analogues and amphenicol antibiotics from phthalate metabolites: the former were detected with a mobile phase of 0.1% ammonium water solution/methanol containing 0.1% ammonium water solution in negative mode, whereas the latter were determined with a mobile phase of 0.1% acetic acid solution/acetonitrile containing 0.1% acetic acid in negative mode. The limits of detection were less than 0.26 ng/mL for bisphenol analogues, 0.12 ng/mL for amphenicol antibiotics, and 0.14 ng/mL for phathalate metabolites. The recoveries of all target analytes in three fortification levels ranged from 72.02 to 117.64% with the relative standard deviations of no larger than 14.51%. The matrix effect was adjusted by isotopically labeled internal standards. This proposed method was successfully applied to analyze 40 actual urines and 13 out of 18 studied compounds were detected. Graphical abstract Simultaneous determination of nine bisphenol analogues, three amphenicol antibiotics, and six phthalate metabolites in human urine samples.

  4. A multiple antibiotic and serum resistant oligotrophic strain, Klebsiella pneumoniae MB45 having novel dfrA30, is sensitive to ZnO QDs

    Directory of Open Access Journals (Sweden)

    Chakrabarti Pinak

    2011-05-01

    Full Text Available Abstract Background The aim of this study was to describe a novel trimethoprim resistance gene cassette, designated dfrA30, within a class 1 integron in a facultatively oligotrophic, multiple antibiotic and human serum resistant test strain, MB45, in a population of oligotrophic bacteria isolated from the river Mahananda; and to test the efficiency of surface bound acetate on zinc oxide quantum dots (ZnO QDs as bactericidal agent on MB45. Methods Diluted Luria broth/Agar (10-3 media was used to cultivate the oligotrophic bacteria from water sample. Multiple antibiotic resistant bacteria were selected by employing replica plate method. A rapid assay was performed to determine the sensitivity/resistance of the test strain to human serum. Variable region of class 1 integron was cloned, sequenced and the expression of gene coding for antibiotic resistance was done in Escherichia coli JM 109. Identity of culture was determined by biochemical phenotyping and 16S rRNA gene sequence analyses. A phylogenetic tree was constructed based on representative trimethoprim resistance-mediating DfrA proteins retrieved from GenBank. Growth kinetic studies for the strain MB45 were performed in presence of varied concentrations of ZnO QDs. Results and conclusions The facultatively oligotrophic strain, MB45, resistant to human serum and ten antibiotics trimethoprim, cotrimoxazole, ampicillin, gentamycin, netilmicin, tobramycin, chloramphenicol, cefotaxime, kanamycin and streptomycin, has been identified as a new strain of Klebsiella pneumoniae. A novel dfr gene, designated as dfrA30, found integrated in class 1 integron was responsible for resistance to trimethoprim in Klebsiella pneumoniae strain MB45. The growth of wild strain MB45 was 100% arrested at 500 mg/L concentration of ZnO QDs. To our knowledge this is the first report on application of ZnO quantum dots to kill multiple antibiotics and serum resistant K. pneumoniae strain.

  5. Practices of self-medication with antibiotics among nursing students of Institute of Nursing, Dow University of Health Sciences, Karachi, Pakistan.

    Science.gov (United States)

    Ali, Akbar Shoukat; Ahmed, Javed; Ali, Akbar Shoukat; Sonekhi, Gomand Beekho; Fayyaz, Nargis; Zainulabdin, Zeeshan; Jindani, Rahim

    2016-02-01

    Self-medication practice among nursing students is of growing concern. Access to drugs and handling them in their future practices make nursing students susceptible to self-prescription and self-medication. This cross-sectional study assesses the prevalence and pattern of self-medication with antibiotics among nursing students of Institute of Nursing, Dow University of Health Sciences, Karachi, Pakistan. A random sample of convenience of 160 nursing students underwent a predesigned questionnaire. More than half of nursing students 79 (52.7%) experienced self-medication with antibiotics. It was more prevalent among males 49 (62%) . Knowledge about the drug 59 (74.7%) and convenience 13 (16.5%) were the key reasons to self-medicate. Fever 37 (46.8%) and sore throat 27 (34.2%) were the common symptoms predisposing to self-medication. Beta-lactam group of antibiotics 35 (44.3%) was most frequent used. Only 26 (32.9%) respondents completed the entire antibiotic course. Efforts must be directed towards educating nursing students about responsible and informed self-medication practices.

  6. Identification of Mycobacterial Genes Involved in Antibiotic Sensitivity: Implications for the Treatment of Tuberculosis with β-Lactam-Containing Regimens

    Science.gov (United States)

    Viswanathan, Gopinath; Yadav, Sangya

    2017-01-01

    ABSTRACT In a Mycobacterium smegmatis mutant library screen, transposon mutants with insertions in fhaA, dprE2, rpsT, and parA displayed hypersusceptibility to antibiotics, including the β-lactams meropenem, ampicillin, amoxicillin, and cefotaxime. Sub-MIC levels of octoclothepin, a psychotic drug inhibiting ParA, phenocopied the parA insertion and enhanced the bactericidal activity of meropenem against Mycobacterium tuberculosis in combination with clavulanate. Our study identifies novel factors associated with antibiotic resistance, with implications in repurposing β-lactams for tuberculosis treatment. PMID:28438925

  7. Incremental cost of nosocomial bacteremia according to the focus of infection and antibiotic sensitivity of the causative microorganism in a university hospital.

    Science.gov (United States)

    Riu, Marta; Chiarello, Pietro; Terradas, Roser; Sala, Maria; Garcia-Alzorriz, Enric; Castells, Xavier; Grau, Santiago; Cots, Francesc

    2017-04-01

    To estimate the incremental cost of nosocomial bacteremia according to the causative focus and classified by the antibiotic sensitivity of the microorganism.Patients admitted to Hospital del Mar in Barcelona from 2005 to 2012 were included. We analyzed the total hospital costs of patients with nosocomial bacteremia caused by microorganisms with a high prevalence and, often, with multidrug-resistance. A control group was defined by selecting patients without bacteremia in the same diagnosis-related group.Our hospital has a cost accounting system (full-costing) that uses activity-based criteria to estimate per-patient costs. A logistic regression was fitted to estimate the probability of developing bacteremia (propensity score) and was used for propensity-score matching adjustment. This propensity score was included in an econometric model to adjust the incremental cost of patients with bacteremia with differentiation of the causative focus and antibiotic sensitivity.The mean incremental cost was estimated at &OV0556;15,526. The lowest incremental cost corresponded to bacteremia caused by multidrug-sensitive urinary infection (&OV0556;6786) and the highest to primary or unknown sources of bacteremia caused by multidrug-resistant microorganisms (&OV0556;29,186).This is one of the first analyses to include all episodes of bacteremia produced during hospital stays in a single study. The study included accurate information about the focus and antibiotic sensitivity of the causative organism and actual hospital costs. It provides information that could be useful to improve, establish, and prioritize prevention strategies for nosocomial infections.

  8. Dual Recognition Strategy for Specific and Sensitive Detection of Bacteria Using Aptamer-Coated Magnetic Beads and Antibiotic-Capped Gold Nanoclusters.

    Science.gov (United States)

    Cheng, Dan; Yu, Mengqun; Fu, Fei; Han, Weiye; Li, Gan; Xie, Jianping; Song, Yang; Swihart, Mark T; Song, Erqun

    2016-01-05

    Food poisoning and infectious diseases caused by pathogenic bacteria such as Staphylococcus aureus (SA) are serious public health concerns. A method of specific, sensitive, and rapid detection of such bacteria is essential and important. This study presents a strategy that combines aptamer and antibiotic-based dual recognition units with magnetic enrichment and fluorescent detection to achieve specific and sensitive quantification of SA in authentic specimens and in the presence of much higher concentrations of other bacteria. Aptamer-coated magnetic beads (Apt-MB) were employed for specific capture of SA. Vancomycin-stabilized fluorescent gold nanoclusters (AuNCs@Van) were prepared by a simple one-step process and used for sensitive quantification of SA in the range of 32-10(8) cfu/mL with the detection limit of 16 cfu/mL via a fluorescence intensity measurement. And using this strategy, about 70 cfu/mL of SA in complex samples (containing 3 × 10(8) cfu/mL of other different contaminated bacteria) could be successfully detected. In comparison to prior studies, the developed strategy here not only simplifies the preparation procedure of the fluorescent probes (AuNCs@Van) to a great extent but also could sensitively quantify SA in the presence of much higher concentrations of other bacteria directly with good accuracy. Moreover, the aptamer and antibiotic used in this strategy are much less expensive and widely available compared to common-used antibodies, making it cost-effective. This general aptamer- and antibiotic-based dual recognition strategy, combined with magnetic enrichment and fluorescent detection of trace bacteria, shows great potential application in monitoring bacterial food contamination and infectious diseases.

  9. [Systemic therapy with anti-infective agents. Principles of rational use of systemic antibiotics in dermatology].

    Science.gov (United States)

    Sunderkötter, C; Brehler, R; Becker, K

    2014-02-01

    dermatological patients the beta-lactam antibiotics penicillin V, penicillin G and cephalosporins of groups 1 and 2 are the antibiotics most commonly indicated for skin and soft tissue infections. If the patient's history arouses the suspicion of incompatibility to these antibiotics, allergological diagnostics should be carried out in order to avoid as often as possible the alternative use of antibiotics which result in more undesired effects and development of resistance.

  10. The prevalence and antibiotic sensitivity of oral Viridans streptococci in healthy children and children with disabilities in Kuwait.

    Science.gov (United States)

    Salako, Nathanael O; Rotimi, Vincent; Philip, Leeba; Haidar, Hussien A; Hamdan, Hussien M

    2007-01-01

    The purpose of this study was to compare the antibiotic susceptibility profiles of Viridans streptococci (VS) isolated from the oral cavity of healthy children and children with disabilities in Kuwait. Plaque samples were collected from the tooth and tongue surfaces of 102 healthy children and 102 children who were intellectually disabled and institutionalized. The resistance to seven antibiotics (amoxicillin, cephalothin, clindamycin, erythromycin, penicillin G, tetracycline, and vancomycin) was tested. A total of 330 (44.5%) VS were isolated from the children who were healthy and 411 (55.5%) from children with disabilities. The most common isolates were S. salivarius (27.3%) in healthy children; S. sanguis (22.6%) was predominant among children who were disabled. S. mutans was found in 12.1% of the healthy children and in 16.5% of the children who were disabled. The combined percentage of resistant strains (healthy and disabled) was found to be highest with amoxicillin (43%) and lowest with vancomycin (12%). S. sanguis, S. mitis and S. oralis were more resistant in healthy children (45%, 56%, and 55% respectively) than in children with disabilities (40%, 47% and 47% respectively). S. mutans was the least resistant species to all antibiotics in both groups of children. About 56% of all streptococci isolated from both groups were resistant to at least one of the antibiotics tested. The data showed that there was a difference in the level of resistance of oral VS isolated from healthy children and children with disabilities to some antibiotics commonly used in dentistry.

  11. Prevalence of bacterial agents isolated from clinical cases of bovine mastitis in the dry period and the determination of their antibiotic sensitivity in Tabriz, Iran

    Directory of Open Access Journals (Sweden)

    Samad Mosaferi

    2015-09-01

    Full Text Available Objective: To determine the prevalence of mastitis-causing bacteria in the dry period and its antibiotic sensitivity. Methods: In this study, 852 dry cows were examined. A total of 30 cows with clinical mastitis symptoms were detected and their milk samples were collected. In order to purify the bacteria, brain heart infusion and blood agar media were applied and single colonies were used for Gram staining, oxidase and catalase testing, cultivating in O-F medium to determine the genus and species of bacteria. Then, antimicrobial susceptibility was tested by the agar disk diffusion method. Results: The prevalence of isolated bacteria was 2.46%, in which coagulase positive Staphylococcus, coagulase negative Staphylococcus, Streptococcus dysgalactiae, Streptococcus faecalis, Escherichia coli, Pseudomonas, Bacillus and yeast were (9/99%, (6/66%, (13/32%, (3/33%, (6/66%, (13/32%, (9/99% and (6/66%, respectively. After tests of antibiotic susceptibility, the most and the least sensitivity were reported to enrofloxacin and ampicillin respectively. Conclusions: This study indicated that Streptococcus dysgalactiae is the most commonly isolated bacteria with the greatest sensitivity to enrofloxacin and tetracycline which can be used to treat mastitis in the dry period in Tabriz.

  12. Aplikace cíleně modifikovaných enzymů v biosyntézách beta-laktamových antibiotik

    OpenAIRE

    Schneiderová, Michaela

    2012-01-01

    Nowadays beta-lactam antibiotics are widely used as bacteriostatic agents. The chemical synthesis of antibiotics or its derivatives could be replaced with biocatalysis. This work deals with basics of industrial synthesis beta-lactam antibiotics and, mainly, with used enzymes. This work acquainted with methodes used in enzyme modifications and improving, so they could fit the best for the industrial syntheses.

  13. Dielectrophoretic assay of bacterial resistance to antibiotics

    International Nuclear Information System (INIS)

    Johari, Juliana; Huebner, Yvonne; Hull, Judith C; Dale, Jeremy W; Hughes, Michael P

    2003-01-01

    The dielectrophoretic collection spectra of antibiotic-sensitive and antibiotic-resistant strains of Staphylococcus epidermidis have been determined. These indicate that in the absence of antibiotic treatment there is a strong similarity between the dielectric properties of sensitive and resistant strains, and that there is a significant difference between the sensitive strains before and after treatment with the antibiotic streptomycin after 24 h exposure. This method offers possibilities for the assessment of bacterial resistance to antibiotics. (note)

  14. Auto Poisoning of the Respiratory Chain by a Quorum Sensing Regulated Molecule Favors Biofilm Formation and Antibiotic Tolerance

    Science.gov (United States)

    Hazan, Ronen; Que, Yok Ai; Maura, Damien; Strobel, Benjamin; Majcherczyk, Paul Anthony; Hopper, Laura Rose; Wilbur, David J.; Hreha, Teri N.; Barquera, Blanca; Rahme, Laurence G.

    2015-01-01

    Summary Bacterial programmed cell death and quorum sensing are direct examples of prokaryote group behaviors, wherein cells coordinate their actions to function cooperatively like one organism for the benefit of the whole culture. We demonstrate here that 2-n-heptyl-4-hydroxyquinoline-N-oxide (HQNO), a Pseudomonas aeruginosa quorum sensing -regulated low-molecular-weight excreted molecule, and triggers autolysis by self-perturbing the electron transfer reactions of the cytochrome bc1 complex. HQNO induces specific self-poisoning by disrupting the flow of electrons through the respiratory chain at the cytochrome bc1 complex, causing a leak of reducing equivalents to O2 whereby electrons that would normally be passed to cytochrome c are donated directly to O2. The subsequent mass production of reactive oxygen species (ROS) reduces membrane potential and disrupts membrane integrity, causing bacterial cell autolysis and DNA release. DNA subsequently promotes biofilm formation and increases antibiotic tolerance to beta-lactams, suggesting that HQNO-dependent cell autolysis is advantageous to the bacterial populations. These data both identify a new programmed cell death system, and a novel role for HQNO as a critical-inducer of biofilm formation and antibiotic tolerance. This newly identified pathway suggests intriguing mechanistic similarities with the initial mitochondrial-mediated steps of eukaryotic apoptosis. PMID:26776731

  15. Infections and use of antibiotics in patients admitted for severe acute pancreatitis: data from the EPIC II study.

    Science.gov (United States)

    De Waele, Jan J; Rello, Jordi; Anzueto, Antonio; Moreno, Rui; Lipman, Jeffrey; Sakr, Yasser; Pickkers, Peter; Leone, Marc; Ferguson, Andrew; Oud, Lavi; Vincent, Jean-Louis

    2014-08-01

    Infectious complications are frequent in severe acute pancreatitis (SAP) but multinational epidemiologic data are lacking. The aim of the study was to analyze the characteristics of the infectious complications and antimicrobial use in this setting. One-day point prevalence study of infection in critically ill patients (Extended Prevalence of Infection in the ICU-II study), performed in 1,265 ICUs in 75 countries. Of the 13,796 patients in the study, 159 were admitted with SAP. One-hundred sixteen (73%) had infections: 31% intra-abdominal, 16% extra-abdominal, and 26% both. Gram-negative bacteria were more prevalent than gram-positive organisms, anaerobes, or fungi. Therapeutically, penicillins and other beta-lactams were used most frequently. Prophylactic antibiotics were administered to 24% of the patients with SAP. Infections are frequent in patients admitted with SAP; most are intra-abdominal infections. Microbiology is diverse with gram-negative micro-organisms most frequently isolated. Most patients admitted to the ICU for SAP receive antibiotics at some point.

  16. Should patients with acute exacerbation of chronic bronchitis be treated with antibiotics? Advantages of the use of fluoroquinolones.

    Science.gov (United States)

    Mensa, J; Trilla, A

    2006-05-01

    The pathological changes in chronic bronchitis (CB) produce airflow obstruction, reduce the effectiveness of the mucocilliary drainage system and lead to bacterial colonisation of bronchial secretion. The presence of bacteria induces an inflammatory response mediated by leukocytes. There is a direct relationship between the degree of impairment of the mucocilliary drainage system, the density of bacteria in mucus and the number of leukocytes in the sputum. Purulent sputum is a good marker of a high bacterial load. Eventually, if the number of leukocytes is high, their normal activity could decrease the effectiveness of the drainage system, increase the bronchial obstruction and probably damage the lung parenchyma. Whenever the density of bacteria in the bronchial lumen is >or=10(6) CFU/mL, there is a high probability that the degree of inflammatory response will lead to a vicious cycle which in turn tends to sustain the process. This situation can arise during the clinical course of any acute exacerbation of CB, independently of its aetiology, provided the episode is sufficiently severe and/or prolonged. Fluoroquinolones of the third and fourth generation are bactericidal against most microorganisms usually related to acute exacerbations of CB. Their diffusion to bronchial mucus is adequate. When used in short (5-day) treatment they reduce the bacterial load in a higher proportion than is achieved by beta-lactam or macrolide antibiotics given orally. Although the clinical cure rate is similar to that obtained with other antibiotics, the time between exacerbations could be increased.

  17. Monitoring and evaluation of antibiotic resistance genes in four municipal wastewater treatment plants in Harbin, Northeast China.

    Science.gov (United States)

    Wen, Qinxue; Yang, Lian; Duan, Ruan; Chen, Zhiqiang

    2016-05-01

    The development and proliferation of antibiotic resistance in pathogenic and environmental microorganisms is of great concern for public health. In this study, the distribution and removal efficiency of intI1 and eight subtypes of antibiotic resistance genes (ARGs) for tetracycline, sulfonamides, beta-lactams resistance in four municipal wastewater treatment plants (WWTPs) in Harbin, which locates in Songhua River basin in cold areas of China, were monitored by real-time fluorescent quantitative PCR. The results showed that intI1 and 6 ARGs except for blaTEM and blaSHV were detected in wastewater and sludge samples and 0.3-2.7 orders of magnitude of ARGs removal efficiency in the four WWTPs were observed. The investigation on the removal of ARGs of different treatment units in one WWTP showed that the biological treatment unit played the most important role in ARGs removal (1.2-1.8 orders of magnitude), followed by UV disinfection, while primary physical treatment units can hardly remove any ARGs. Although all the WWTPs can remove ARGs effectively, ARGs concentrations are still relatively high in the effluent, their further attenuation should be investigated. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Low antibiotic resistance among anaerobic Gram-negative bacteria in periodontitis 5 years following metronidazole therapy.

    Science.gov (United States)

    Dahlen, G; Preus, H R

    2017-02-01

    The objective of this study was to assess antibiotic susceptibility among predominant Gram-negative anaerobic bacteria isolated from periodontitis patients who 5 years prior had been subject to mechanical therapy with or without adjunctive metronidazole. One pooled sample was taken from the 5 deepest sites of each of 161 patients that completed the 5 year follow-up after therapy. The samples were analyzed by culture. A total number of 85 anaerobic strains were isolated from the predominant subgingival flora of 65/161 patient samples, identified, and tested for antibiotic susceptibility by MIC determination. E-tests against metronidazole, penicillin, amoxicillin, amoxicillin + clavulanic acid and clindamycin were employed. The 73/85 strains were Gram-negative rods (21 Porphyromonas spp., 22 Prevotella/Bacteroides spp., 23 Fusobacterium/Filifactor spp., 3 Campylobacter spp. and 4 Tannerella forsythia). These were all isolated from the treated patients irrespective of therapy procedures (+/-metronidazole) 5 years prior. Three strains (Bifidobacterium spp., Propionibacterium propionicum, Parvimonas micra) showed MIC values for metronidazole over the European Committee on Antimicrobial Susceptibility Testing break point of >4 μg/mL. All Porphyromonas and Tannerella strains were highly susceptible. Metronidazole resistant Gram-negative strains were not found, while a few showed resistance against beta-lactam antibiotics. In this population of 161 patients who had been subject to mechanical periodontal therapy with or without adjunct metronidazole 5 years prior, no cultivable antibiotic resistant anaerobes were found in the predominant subgingival microbiota. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Antibiotics and Antibiotic Resistance

    Science.gov (United States)

    ... all that ails you. Antibiotics, also known as antimicrobial drugs, are drugs that fight infections caused by bacteria. ... Information for Consumers and Health Professionals Information by drug class Antimicrobial Resistance Animal and Veterinary Related Resources Further information ...

  20. In vitro activity of fluoroquinolones (gatifloxacin, levofloxacin and trovafloxacin and seven other antibiotics against Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Nicodemo A.C.

    2001-01-01

    Full Text Available In recent years, the level of resistance of S. pneumoniae to beta-lactam and/or macrolides has increased around the world including some countries in South America. Because of this resistance, it is necessary to test the therapeutic alternatives for treating this pathogen, including the newer quinolones. This study was carried out in order to compare the in vitro activity of fluoroquinolones gatifloxacin, levofloxacin and trovafloxacin, to penicillin G, amoxicillin, amoxicillin-clavulanate, cufuroxime sodium, ceftriaxone, azithromycin and clarithromycin, against 300 strains of S. pneumoniae. Of the 300 samples tested, 18.6% were not susceptible to penicillin (56 strains and 7% (21 strains were resistant to the second generation cephalosporin. Among the macrolides, resistance ranged from 6.7% for clarithromycin to 29.6% for azithromycin. Susceptibility to the newer quinolones was 100% including the 56 strains not susceptible to penicillin. Among the 10 antibiotics evaluated, the fluoroquinolones gatifloxacin, levofloxacin, and trovafloxacin displayed high levels of in vitro activity against S. pneumoniae.

  1. Seasonal variations in antibiotic resistance gene transport in the Almendares River, Havana, Cuba

    Directory of Open Access Journals (Sweden)

    Charles W Knapp

    2012-11-01

    Full Text Available Numerous studies have quantified antibiotic resistance genes (ARG in rivers and streams around the world, and significant relationships have been shown that relate different pollutant outputs and increased local ARG levels. However, most studies have not considered ambient flow conditions, which can vary dramatically especially in tropical countries. Here, ARG were quantified in water-column and sediment samples during the dry-and wet-seasons to assess how seasonal and other factors influence ARG transport down the Almendares River (Havana, Cuba. Eight locations were sampled and stream flow estimated during both seasons; qPCR was used to quantify four tetracycline, two erythromycin, and three beta-lactam resistance genes. ARG concentrations were higher in wet-season versus dry-season samples, which combined with higher flows, indicated greater ARG transport downstream during the wet season. Water-column ARG levels were more spatially variable in the dry-season than the wet-season, with the proximity of waste outfalls strongly influencing local ARG levels. Results confirm that dry-season sampling provides a useful picture of the impact of individual waste inputs on local stream ARG levels, whereas, the majority of ARGs in this tropical river were transported downstream during the wet season, possibly due to re-entrainment of ARG from sediments.

  2. Tracking antibiotic resistome during wastewater treatment using high throughput quantitative PCR.

    Science.gov (United States)

    An, Xin-Li; Su, Jian-Qiang; Li, Bing; Ouyang, Wei-Ying; Zhao, Yi; Chen, Qing-Lin; Cui, Li; Chen, Hong; Gillings, Michael R; Zhang, Tong; Zhu, Yong-Guan

    2018-05-08

    Wastewater treatment plants (WWTPs) contain diverse antibiotic resistance genes (ARGs), and thus are considered as a major pathway for the dissemination of these genes into the environments. However, comprehensive evaluations of ARGs dynamic during wastewater treatment process lack extensive investigations on a broad spectrum of ARGs. Here, we investigated the dynamics of ARGs and bacterial community structures in 114 samples from eleven Chinese WWTPs using high-throughput quantitative PCR and 16S rRNA-based Illumina sequencing analysis. Significant shift of ARGs profiles was observed and wastewater treatment process could significantly reduce the abundance and diversity of ARGs, with the removal of ARGs concentration by 1-2 orders of magnitude. Whereas, a considerable number of ARGs were detected and enriched in effluents compared with influents. In particular, seven ARGs mainly conferring resistance to beta-lactams and aminoglycosides and three mobile genetic elements persisted in all WWTPs samples after wastewater treatment. ARGs profiles varied with wastewater treatment processes, seasons and regions. This study tracked the footprint of ARGs during wastewater treatment process, which would support the assessment on the spread of ARGs from WWTPs and provide data for identifying management options to improve ARG mitigation in WWTPs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Study on isolation, molecular detection of virulence gene and antibiotic sensitivity pattern of Escherichia coli isolated from milk and milk products

    Directory of Open Access Journals (Sweden)

    M. N. Brahmbhatt

    2013-06-01

    Full Text Available Aim: The study was undertaken to isolate pathogenic E. coli from milk and various milk products, detection of virulence gene using Polymerase chain reaction (PCR and investigate their antibiotic sensitivity pattern. Materials and Methods: Altogether 250 milk and various milk products samples consisting of raw milk (50, cheese (50, ice-cream (50, mawa (50 and dahi (50 were collected from milk vendors, retail shops located in Anand city, under aseptic precautions. For the enrichment of the organism from the collected samples, MacConkey broth was used and inoculation was carried out on MacConkey agar and EMB agar. Later on, to confirm the isolates, various biochemical tests such as IMViC test, Urease test were performed. Evaluation of antibiotic sensitivity pattern of E. coli was assessed by disk diffusion method. Finally the E. coli isolates were screened for the presence of virulence associated genes by PCR . Results: The prevalence of E. coli was observed 32 % in the samples comprising of milk (52.00%, cheese (28.00%, icecream (20.00%, mawa (44.00%, and dahi (16.00%. Antibiotic sensitivity was recorded high for Co-trimoxazole (100% followed by Gentamicin (96.73%, Trimithoprime (93.47% and Doxycycline hydochloride (92.39%. Least sensitivity was recorded for Ampicillin (8.69%. In this study, out of 80 E. coli isolates, 25 isolates (31.25% were positive for stx genes, of which 7 (8.75% isolates were positive for stx1 gene only, while 12 (15.00% isolates were positive for stx2 gene only and 5 (6.25% isolates were positive for both stx1 and stx2, 7 isolates (8.75% were positive for eaeA gene and all the isolate were negetive for rfb O157 gene. Conclusions: Current study supports the finding that raw milk and various milk products can be regarded as critical source of pathogenic E. coli This explains the need of strict monitoring and surveillance for effective measures of hygiene and sanitary practice during production of milk and various milk

  4. Validation of a Five Plate Test, the STAR protocol, for the screening of antibiotic residues in muscle from different animal species according to European Decision 2002/657/EC.

    Science.gov (United States)

    Gaudin, V; Hedou, C; Rault, A; Verdon, E

    2010-07-01

    The STAR protocol is a Five Plate Test (FPT) developed several years ago at the Community Reference Laboratory (CRL) for the screening of antimicrobial residues in milk and muscle. This paper presents the validation of this method according to European Decision 2002/657/EC and to an internal guideline for validation. A validation protocol based on 'simulated tissues' and on a list of 16 representative antimicrobials to be validated was implemented in our laboratory during several months for the STAR protocol. The performance characteristics of the method were determined (specificity, detection capabilities CCbeta, applicability, ruggedness). In conclusion, the STAR protocol is applicable to the broad-spectrum detection of antibiotic residues in muscles of different animal species (pig, cattle, sheep, poultry). The method has good specificity (false-positive rate = 4%). The detection capabilities were determined for 16 antibiotics from different families in relation to their respective maximum residue limit (MRL): beta-lactams (penicillins and cephalosporins 8 MRL) and florfenicol (MRL). The two objectives of this study were met: firstly, to validate the STAR protocol according to European Decision 2002/657/EC, then to demonstrate that the validation guideline developed to implement this decision is applicable to microbiological plate tests even for muscle. The use of simulated tissue appeared a good compromise between spiked discs with antibiotic solutions and incurred tissues. In addition, the choice of a list of representative antibiotics allowed the reduction of the scope of the validation, which was already costly in time and effort.

  5. Bacterial cheating limits antibiotic resistance

    Science.gov (United States)

    Xiao Chao, Hui; Yurtsev, Eugene; Datta, Manoshi; Artemova, Tanya; Gore, Jeff

    2012-02-01

    The widespread use of antibiotics has led to the evolution of resistance in bacteria. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removing the antibiotic. The cooperative nature of this growth suggests that a cheater strain---which does not contribute to breaking down the antibiotic---may be able to take advantage of cells cooperatively inactivating the antibiotic. Here we find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We observe stable coexistence between the two strains and find that a simple model successfully explains the behavior as a function of antibiotic concentration and cell density. We anticipate that our results will provide insight into the evolutionary origin of phenotypic diversity and cooperative behaviors.

  6. Evaluation of antibiotic self-medication among outpatients of the state university hospital of Port-Au-Prince, Haiti: a cross-sectional study.

    Science.gov (United States)

    Moise, Kenny; Bernard, Joseph Junior; Henrys, Jean Hugues

    2017-01-01

    In Haiti, where all drugs are available over the counter, self-medication with antibiotics appears as a common practice. Inappropriate use of beta-lactams and macrolides is likely to contribute to the development of antimicrobial resistance. This study aimed to (i) assess the extent of self-medication with antibiotics, (ii) explore the contributing factors (age, gender and educational background) and (iii) identify specific antibiotic drug classes used among patients attending the outpatient clinic of the State University Hospital of Port-au-Prince. A cross-sectional survey among 200 outpatients of the State University Hospital of Port-au-Prince was conducted in December 2014. Face-to-face interviews were conducted using a standardized questionnaire. Parents of pediatric patients were allowed to answer to questions on their behalf. Among the study sample, 45.5% practiced self-medication with antibiotics. It was less prevalent among patients with the highest education level (23.1%; OR: 0.89 (0.5-1.75), p = 0.001). Mild symptoms (28.6%) and vaginal itching (44.4%) were the main reasons for self-medication with antibiotics. Self-medication using amoxicillin was reported by 67.0%. Self-medication with antibiotics is a common practice among Haitian patients and is more common among the less educated. Amoxicillin for urinary tract infections is the most commonly used medication. It is crucial to raise awareness on the dangers of the practice in the population and inforce the current law regarding the use of over the counter antibiotics.

  7. The comparison of printed resources bacterial contamination in libraries of Al-Zahra Hospital and Sciences Faculty of Isfahan University and the determination of their antibiotic sensitivity pattern.

    Science.gov (United States)

    Rafiei, Hosein; Chadeganipour, Mostafa; Ojaghi, Rezvan; Maracy, Mohammad Reza; Nouri, Rasool

    2017-01-01

    During the library loan process, the printed resources can be a carrier of pathogenic bacteria. In this study, it was tried to compare the Bacterial Contamination Rates and their antibiotic sensitivity pattern in printed resources of a hospital and a non-hospital library. This is a cross-sectional study. Returning books from the Al-Zahra hospital library and library of Sciences faculty of Isfahan University provides the research community. The sample size, 96 cases, was calculated using quota sampling. For sampling sterile swab dipped in trypticase soy broth medium and transfer trypticase soy broth medium were used. To identify different type of isolated bacteria from Gram-staining test and biochemical tests such as; TSI, IMViC and etc., were used. 76 (79.2%) and 20 (20.8%) of cultured samples were negative and positive, the respectively. Of 20 positive samples, 11 samples (55%) belong to the family Enterobacteriaceae that after detecting by Differential teste identified all 11 samples of Enterobacter that all of them were sensitive to Gentamicin and Ofloxacin. Also the most resistance to Nitrofurantoin and Amikacin was observed. 9 cases remained (45%) were coagulase-negative Staphylococcus that all of them were sensitive to the Trimethoprim-sulfamethoxazole and Cephalexin antibiotics also the most resistance to Cefixime was observed. Considering that the Enterobacter sp and coagulase-negative Staphylococcus were separated from the books, the books as well as other hospital and medical equipment can transmit the infection to librarians, library users, patients and hospital staff, and also it can produce serious infections in patients with immune deficiency.

  8. Microbial Contaminants of Cord Blood Units Identified by 16S rRNA Sequencing and by API Test System, and Antibiotic Sensitivity Profiling.

    Directory of Open Access Journals (Sweden)

    Luís França

    Full Text Available Over a period of ten months a total of 5618 cord blood units (CBU were screened for microbial contamination under routine conditions. The antibiotic resistance profile for all isolates was also examined using ATB strips. The detection rate for culture positive units was 7.5%, corresponding to 422 samples.16S rRNA sequence analysis and identification with API test system were used to identify the culturable aerobic, microaerophilic and anaerobic bacteria from CBUs. From these samples we recovered 485 isolates (84 operational taxonomic units, OTUs assigned to the classes Bacteroidia, Actinobacteria, Clostridia, Bacilli, Betaproteobacteria and primarily to the Gammaproteobacteria. Sixty-nine OTUs, corresponding to 447 isolates, showed 16S rRNA sequence similarities above 99.0% with known cultured bacteria. However, 14 OTUs had 16S rRNA sequence similarities between 95 and 99% in support of genus level identification and one OTU with 16S rRNA sequence similarity of 90.3% supporting a family level identification only. The phenotypic identification formed 29 OTUs that could be identified to the species level and 9 OTUs that could be identified to the genus level by API test system. We failed to obtain identification for 14 OTUs, while 32 OTUs comprised organisms producing mixed identifications. Forty-two OTUs covered species not included in the API system databases. The API test system Rapid ID 32 Strep and Rapid ID 32 E showed the highest proportion of identifications to the species level, the lowest ratio of unidentified results and the highest agreement to the results of 16S rRNA assignments. Isolates affiliated to the Bacilli and Bacteroidia showed the highest antibiotic multi-resistance indices and microorganisms of the Clostridia displayed the most antibiotic sensitive phenotypes.

  9. Microbial Contaminants of Cord Blood Units Identified by 16S rRNA Sequencing and by API Test System, and Antibiotic Sensitivity Profiling.

    Science.gov (United States)

    França, Luís; Simões, Catarina; Taborda, Marco; Diogo, Catarina; da Costa, Milton S

    2015-01-01

    Over a period of ten months a total of 5618 cord blood units (CBU) were screened for microbial contamination under routine conditions. The antibiotic resistance profile for all isolates was also examined using ATB strips. The detection rate for culture positive units was 7.5%, corresponding to 422 samples.16S rRNA sequence analysis and identification with API test system were used to identify the culturable aerobic, microaerophilic and anaerobic bacteria from CBUs. From these samples we recovered 485 isolates (84 operational taxonomic units, OTUs) assigned to the classes Bacteroidia, Actinobacteria, Clostridia, Bacilli, Betaproteobacteria and primarily to the Gammaproteobacteria. Sixty-nine OTUs, corresponding to 447 isolates, showed 16S rRNA sequence similarities above 99.0% with known cultured bacteria. However, 14 OTUs had 16S rRNA sequence similarities between 95 and 99% in support of genus level identification and one OTU with 16S rRNA sequence similarity of 90.3% supporting a family level identification only. The phenotypic identification formed 29 OTUs that could be identified to the species level and 9 OTUs that could be identified to the genus level by API test system. We failed to obtain identification for 14 OTUs, while 32 OTUs comprised organisms producing mixed identifications. Forty-two OTUs covered species not included in the API system databases. The API test system Rapid ID 32 Strep and Rapid ID 32 E showed the highest proportion of identifications to the species level, the lowest ratio of unidentified results and the highest agreement to the results of 16S rRNA assignments. Isolates affiliated to the Bacilli and Bacteroidia showed the highest antibiotic multi-resistance indices and microorganisms of the Clostridia displayed the most antibiotic sensitive phenotypes.

  10. The regulation of virulence in phytopathogenic Erwinia species: quorum sensing, antibiotics and ecological considerations.

    Science.gov (United States)

    Whitehead, Neil A; Byers, Joseph T; Commander, Paul; Corbett, Mark J; Coulthurst, Sarah J; Everson, Lee; Harris, Abigail K P; Pemberton, Clare L; Simpson, Natalie J L; Slater, Holly; Smith, Debra S; Welch, Martin; Williamson, Neil; Salmond, George P C

    2002-08-01

    Erwinia carotovora is a Gram-negative bacterial phytopathogen that causes soft-rot disease and potato blackleg. The organism is environmentally widespread and exhibits an opportunistic plant pathogenesis. The ability to secrete multiple plant cell wall-degrading enzymes is a key virulence trait and exoenzyme production is responsive to multiple environmental and physiological cues. One important cue is the cell population density of the pathogen. Cell density is monitored via an acylated homoserine lactone (acyl HSL) signalling molecule, which is thought to diffuse between Erwinia cells in a process now commonly known as 'quorum sensing'. This molecule also acts as the chemical communication signal controlling production of a broad-spectrum beta-lactam antibiotic (1-carbapen-2-em-3-carboxylic acid; carbapenem) synthesised in concert with exoenzyme elaboration, possibly for niche defence. In antibiotic production control, quorum sensing acts at the level of transcriptional activation of the antibiotic biosynthetic cluster. This is achieved via a dedicated LuxR-type protein, CarR that is bound to the signalling molecule. The molecular relay connecting acyl HSL production and exoenzyme induction is not clear, despite the identification of a multitude of global regulatory genes, including those of the RsmA/rsmB system, impinging on enzyme synthesis. Quorum sensing control mediated by acyl HSLs is widespread in Gram-negative bacteria and is responsible for the regulation of diverse phenotypes. Although there is still a paucity of meaningful information on acyl HSL availability and in-situ biological function, there is growing evidence that such molecules play significant roles in microbial ecology.

  11. Considerations for effect site pharmacokinetics to estimate drug exposure: concentrations of antibiotics in the lung.

    Science.gov (United States)

    Rodvold, Keith A; Hope, William W; Boyd, Sara E

    2017-10-01

    Bronchoalveolar lavage (BAL) and microdialysis have become the most reliable and relevant methods for measuring lung concentrations of antibiotics, with the majority of BAL studies involving either healthy adult subjects or patients undergoing diagnostic bronchoscopy. Emphasis on the amount of drug that reaches the site of infection is increasingly recognized as necessary to determine whether a dose selection will translate to good clinical outcomes in the treatment of patients with pneumonia. Observed concentrations and/or parameters of exposure (e.g. area-under-the-curve) need to be incorporated with pharmacokinetic-pharmacodynamic indices so that rational dose selection can be identified for specific pathogens and types of pneumonic infection (community-acquired vs hospital-acquired bacterial pneumonia, including ventilator-associated bacterial pneumonia). Although having measured plasma or lung concentration-time data from critically ill patients to incorporate into pharmacokinetic-pharmacodynamic models is very unlikely during drug development, it is essential that altered distribution, augmented renal clearance, and renal or hepatic dysfunction should be considered. Notably, the number of published studies involving microdialysis and intrapulmonary penetration of antibiotics has been limited and mainly involve beta-lactam agents, levofloxacin, and fosfomycin. Opportunities to measure in high-resolution effect site spatial pharmacokinetics (e.g. with MALDI-MSI or PET imaging) and in vivo continuous drug concentrations (e.g. with aptamer-based probes) now exist. Going forward these studies could be incorporated into antibiotic development programs for pneumonia in order to further increase the probability of candidate success. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Antibiotic Susceptibility of Coagulase-Negative Staphylococci Isolated from Bovine Subclinical Mastitis in Turkey

    Directory of Open Access Journals (Sweden)

    Beytullah Kenar*, Yahya Kuyucuoğlu and Esra Şeker

    2012-06-01

    Full Text Available A total of 572 California Mastitis Test (CMT positive milk samples were collected from 423 lactating cows on 18 private farms in the Middle Western Anatolia. Coagulase–negative staphylococci colonies and CNS species identification was performed based on conventional biochemical techniques and using the API Staph test. Slime production was detected by Congo Red Agar (CRA method. The antibiotic susceptibility was determined according to the National Committee for Clinical Laboratory Standards guidelines (NCCLS. A total of 67 (11.7% coagulase-negative staphylococci (CNS were isolated from CMT positive milk samples. In total, 11 CNS species: S. epidermidis (n=18, S. simulans (n=14, S. warneri (n=10, S. hominis (n=5, S. chromogenes (n=4, S. caprae (n=4, S. xylosus (n=3, S. haemolyticus (n=3, S. hyicus (n=3, S. cohnii (n=2, and S. capitis (n=1 were identified. The most commonly identified CNS species were Staphylococcus epidermidis (26.8% and Staphylococcus simulans (20.8% followed by Staphylococcus warneri (14.9%. Out of 67 CNS isolates, slime production was found in 37 (55.2% CNS strains. CNS isolates were the most resistance to trimethoprim+sulphamethoxazole (76.2%, erythromycin (73.2%, oxacillin and ampicillin (70.2% followed by penicillin (58.3%, gentamicin (53.8%, tetracycline (52.3%, vancomycin (51.8%, ciprofloxacin (26.9%, cefoxitim (23.9%, and cephalothin (13.5%. These results indicate that CNS species are resistant at high rates to the beta-lactam antibiotics which are intensively used in the prevention and treatment of mastitis without any antibiotic susceptibility test in the Middle Western of Turkey.

  13. Dgroup: DG00593 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG00593 Chemical ... DGroup Doripenem ... D03895 ... Doripenem (USAN/INN) ... D01836 ... Doripene...m hydrate (JAN) ... Antibacterial ... DG01710 ... beta-Lactam antibiotic ... DG01713 ... Penicillin skeleton group ... DG01458 ... Carbapene...m ATC code: J01DH04 beta-Lactam antibiotics, carbapenem penicillin binding protein ...

  14. Dgroup: DG00592 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG00592 Chemical ... DGroup Ertapenem ... D07908 ... Ertapenem (INN) D04049 ... Ertapenem sod...ium (USAN) ... Antibacterial ... DG01710 ... beta-Lactam antibiotic ... DG01713 ... Penicillin skeleton group ... DG01458 ... Carbapene...m ATC code: J01DH03 beta-Lactam antibiotics, carbapenem penicillin binding protein ...

  15. Dgroup: DG01212 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG01212 Chemical ... DGroup Imipenem ... D04515 ... Imipenem (INN) D00206 ... Imipenem (USP); Imipene...m hydrate (JP17) Antibacterial ... DG01710 ... beta-Lactam antibiotic ... DG01713 ... Penicillin skeleton group ... DG01458 ... Carbapene...m ... beta-Lactam antibiotics, carbapenem penicillin binding protein ...

  16. Molecular Detection and Sensitivity to Antibiotics and Bacteriocins of Pathogens Isolated from Bovine Mastitis in Family Dairy Herds of Central Mexico

    Directory of Open Access Journals (Sweden)

    Ma. Fabiola León-Galván

    2015-01-01

    Full Text Available Thirty-two farms (n=535 cows located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM and clinical mastitis (CLM were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT (≥3 and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY, lactation number (LN, herd size (HS, and number of days in milk (DM were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH, LN, HS, and DM P<0.01, and correlations between udder quarters from the CMT were around 0.49 P<0.01. Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.

  17. [Nationwide sensitivity surveillance of ciprofloxacin and various parenteral antibiotics against bacteria isolated from patients with severe infections--the first Ciproxan IV special investigation in 2001].

    Science.gov (United States)

    Yamaguchi, Keizo; Ishii, Yoshikazu; Iinuma, Yoshitsugu; Yamanaka, Kiyoharu; Ichiyama, Satoshi; Watanabe, Naoki; Uehara, Nobuyuki; Kaku, Mitsuo; Kurokawa, Yukinori; Hayashi, Mutsumu; Hirakata, Yoichi

    2003-12-01

    The parenteral injection of ciprofloxacin (CPFX), a fluoroquinolone antimicrobial drug, was approved in September 2000 and a re-examination period of 6 years was set at that time. As a special investigation to apply for re-examination of this drug, it has been planned to conduct 3 nationwide surveillances during the re-examination period by collecting clinically isolated bacteria from patients with severe infections, to whom the drug was mainly indicated, and examining drug susceptibilities of the bacteria to various parenteral antimicrobial drugs including CPFX. This time, we determined the minimum inhibitory concentrations (MICs) of various parenteral antimicrobial drugs including CPFX against 1,220 strains isolated from patients with severe infections by the micro-liquid dilution method and compared susceptibilities of various clinically isolated bacteria to CPFX with those to other antimicrobial drugs. Gram-positive bacteria were less susceptible to CPFX than to carbapenems except 2 bacterial species, Enterococcus faecium and Enterococcus avium but susceptibilities of methicillin-susceptible Staphylococcus aureus (MSSA), Staphylococcus epidermidis and Enterococcus faecalis to CPFX were comparable to those to cefozopran. Susceptibility of Streptococcus pneumoniae to CPFX did not differ among ampicillin (ABPC)-susceptible Streptococcus pneumoniae (MIC of ABPC: MIC of ABPC: 0.25-2 micrograms/ml) and ABPC-resistant S. pneumoniae (MIC of ABPC: > or = 4 micrograms/ml) MIC90 of CPFX: 1 microgram/ml) and a decrease in the antimicrobial activity seen among cephem and carbapenem antimicrobial drugs against penicillin-intermediate strains was not noted with CPFX. Gram-negative bacteria were susceptible to CPFX similarly to carbapenems and the MIC90 values of CPFX were in the range from MIC90 was 2 micrograms/ml. CPFX also showed the lowest MIC90 value (0.5 microgram/ml) against beta-lactam-resistant P. aeruginosa among the drugs examined. When extended-spectrum beta

  18. Method of treating depression

    Science.gov (United States)

    Henn, Fritz [East Patchogue, NY

    2012-01-24

    Methods for treatment of depression-related mood disorders in mammals, particularly humans are disclosed. The methods of the invention include administration of compounds capable of enhancing glutamate transporter activity in the brain of mammals suffering from depression. ATP-sensitive K.sup.+ channel openers and .beta.-lactam antibiotics are used to enhance glutamate transport and to treat depression-related mood disorders and depressive symptoms.

  19. Occurrence and persistence of antibiotic resistance genes in river biofilms after wastewater inputs in small rivers

    International Nuclear Information System (INIS)

    Proia, Lorenzo; Schiller, Daniel von; Sànchez-Melsió, Alexandre; Sabater, Sergi; Borrego, Carles M.; Rodríguez-Mozaz, Sara; Balcázar, José Luis

    2016-01-01

    The extensive use of antibiotics in human and veterinary medicine and their subsequent release into the environment may have direct consequences for autochthonous bacterial communities, especially in freshwater ecosystems. In small streams and rivers, local inputs of wastewater treatment plants (WWTPs) may become important sources of organic matter, nutrients and emerging pollutants, such as antibiotic resistance genes (ARGs). In this study, we evaluated the effect of WWTP effluents as a source of ARGs in river biofilms. The prevalence of genes conferring resistance to main antibiotic families, such as beta-lactams (bla_C_T_X_-_M), fluoroquinolones (qnrS), sulfonamides (sul I), and macrolides (ermB), was determined using quantitative PCR (qPCR) in biofilm samples collected upstream and downstream WWTPs discharge points in four low-order streams. Our results showed that the WWTP effluents strongly modified the hydrology, physico-chemistry and biological characteristics of the receiving streams and favoured the persistence and spread of antibiotic resistance in microbial benthic communities. It was also shown that the magnitude of effects depended on the relative contribution of each WWTP to the receiving system. Specifically, low concentrations of ARGs were detected at sites located upstream of the WWTPs, while a significant increase of their concentrations was observed in biofilms collected downstream of the WWTP discharge points (particularly ermB and sul I genes). These findings suggest that WWTP discharges may favour the increase and spread of antibiotic resistance among streambed biofilms. The present study also showed that the presence of ARGs in biofilms was noticeable far downstream of the WWTP discharge (up to 1 km). It is therefore reasonable to assume that biofilms may represent an ideal setting for the acquisition and spread of antibiotic resistance determinants and thus be considered suitable biological indicators of anthropogenic pollution by active

  20. The Prevalence of Antibiotic and Toothpaste Sensitivity found in Oral Streptococcal Isolates in Healthy Individuals in the Okada Community of Nigeria

    Directory of Open Access Journals (Sweden)

    Maureen U Okwu

    2017-04-01

    Full Text Available Background: This study aimed to determine the prevalence, antibiotic, and toothpaste sensitivity of oral streptococcal isolates in healthy individuals in the Okada community of Nigeria. Methods: Oral samples were collected from 230 volunteers and were subjected to standard microbiological tests. Antibacterial sensitivity tests were carried out on the streptococcal isolates that were obtained using a disk diffusion technique, and eight kinds of toothpaste (A-H were screened for their antibacterial effects on Streptococcus mutans (S. mutans. Results: The prevalence of oral streptococci found in this study was 26.1% and the predominant species was S. salivarius (13.9%. S. salivarius was highly resistant to cloxacillin (100% and Augmentin (96.9%, whilst resistance to gentamicin and erythromycin was low at 21.9% and 3.1% respectively. S. mutans were completely sensitive to gentamicin whilst resistance to erythromycin was 33.3%. The entire Streptococcus species showed the lowest resistance to erythromycin (20.0%, followed by gentamicin (31.7%. At 100 mg/mL all toothpaste samples had antibacterial effects on S. mutans. At 50 mg/mL all samples except toothpastes G and H inhibited the bacterium. Toothpastes A and E had the lowest minimum inhibitory concentration of 25 mg/mL. Conclusions: Toothpastes A and E were the most effective toothpastes of the eight assessed in this study.

  1. Investigation of Antibiotic Susceptibility Pattern of Staphylococcus aureus Strains Isolated from Patients Referring to Some Treatment Centers of Qom City, Iran

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    Sara Mosaei

    2017-07-01

    Full Text Available Background and Objectives: Staphylococcus aureus is one of the important causes of nosocomial infections. Resistance to various antibiotics, such as beta-lactams, aminoglycosides, and macrolides is one of the major problems in treatment and prevention of infections caused by this bacterium. Therefore, accurate determination of antibiotic susceptibility pattern of organisms isolated from patients can be beneficial in treatment and prevention of dangerous infections. The objective of this study was to isolate S. aureus bacterium and to determine the antibiotic susceptibility pattern of the isolated strains in patients referred to some treatment centers of Qom city. Methods: In this descriptive cross-sectional study, 340 clinical samples, were collected from September 2016 to July 2017. After isolation and primary identification of S. aureus isolates (using standard bacteriology methods, the isolated strains were confirmed by PCR technique and amplification of femA gene as a molecular diagnostic marker of S. aureus. Finally, antibiotic susceptibility pattern of the strains, was determined by disk diffusion method according to CLSI guideline. Results: Out of 340 clinical samples, 86 S. aureus strains were isolated and identified based on phenotypic characteristics. The femA gene was observed only in 45 strains (52.32% based on molecular analysis. The results of the antibiotic susceptibility test showed that the highest resistance was to penicillin (86.04% and the lowest resistance was to chloramphenicol (0%. Conclusion: The results of this study indicated that femA gene cannot by itself identify all the S. aureus strains. Also, with regard to the results of antibiogram test, it seems that antibiotic susceptibility test is necessary for S. aureus strains isolated from patients.

  2. Inferring relationships between clinical mastitis, productivity and fertility: a recursive model application including genetics, farm associated herd management, and cow-specific antibiotic treatments.

    Science.gov (United States)

    Rehbein, Pia; Brügemann, Kerstin; Yin, Tong; V Borstel, U König; Wu, Xiao-Lin; König, Sven

    2013-10-01

    respect to the previous LCM was close to zero. Estimated recursive effects between SCS and CM were positive, implying strong phenotypic impacts between both traits. Structural equation coefficients explained a detrimental impact of CM on female fertility traits CTFS and SFI. The cow-specific CM treatment had no significant impact on performance traits in the ongoing lactation. For most treatments, beta-lactam-antibiotics were used, but test-day SCS and production traits after the beta-lactam-treatment were comparable to those after other antibiotic as well as homeopathic treatments. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. In vitro susceptibility of Borrelia burgdorferi isolates to three antibiotics commonly used for treating equine Lyme disease.

    Science.gov (United States)

    Caol, Sanjie; Divers, Thomas; Crisman, Mark; Chang, Yung-Fu

    2017-09-29

    Lyme disease in humans is predominantly treated with tetracycline, macrolides or beta lactam antibiotics that have low minimum inhibitory concentrations (MIC) against Borrelia burgdorferi. Horses with Lyme disease may require long-term treatment making frequent intravenous or intramuscular treatment difficult and when administered orally those drugs may have either a high incidence of side effects or have poor bioavailability. The aim of the present study was to determine the in vitro susceptibility of three B. burgdorferi isolates to three antibiotics of different classes that are commonly used in practice for treating Borrelia infections in horses. Broth microdilution assays were used to determine minimum inhibitory concentration of three antibiotics (ceftiofur sodium, minocycline and metronidazole), for three Borrelia burgdorferi isolates. Barbour-Stoner-Kelly (BSK K + R) medium with a final inoculum of 10 6 Borrelia cells/mL and incubation periods of 72 h were used in the determination of MICs. Observed MICs indicated that all isolates had similar susceptibility to each drug but susceptibility to the tested antimicrobial agents varied; ceftiofur sodium (MIC = 0.08 μg/ml), minocycline hydrochloride (MIC = 0.8 μg/ml) and metronidazole (MIC = 50 μg/ml). The MIC against B. burgorferi varied among the three antibiotics with ceftiofur having the lowest MIC and metronidazole the highest MIC. The MIC values observed for ceftiofur in the study fall within the range of reported serum and tissue concentrations for the drug metabolite following ceftiofur sodium administration as crystalline-free acid. Minocycline and metronidazole treatments, as currently used in equine practice, could fall short of attaining MIC concentrations for B. burgdorferi.

  4. Catalogue of antibiotic resistome and host-tracking in drinking water deciphered by a large scale survey.

    Science.gov (United States)

    Ma, Liping; Li, Bing; Jiang, Xiao-Tao; Wang, Yu-Lin; Xia, Yu; Li, An-Dong; Zhang, Tong

    2017-11-28

    Excesses of antibiotic resistance genes (ARGs), which are regarded as emerging environmental pollutants, have been observed in various environments. The incidence of ARGs in drinking water causes potential risks to human health and receives more attention from the public. However, ARGs harbored in drinking water remain largely unexplored. In this study, we aimed at establishing an antibiotic resistome catalogue in drinking water samples from a wide range of regions and to explore the potential hosts of ARGs. A catalogue of antibiotic resistome in drinking water was established, and the host-tracking of ARGs was conducted through a large-scale survey using metagenomic approach. The drinking water samples were collected at the point of use in 25 cities in mainland China, Hong Kong, Macau, Taiwan, South Africa, Singapore and the USA. In total, 181 ARG subtypes belonging to 16 ARG types were detected with an abundance range of 2.8 × 10 -2 to 4.2 × 10 -1 copies of ARG per cell. The highest abundance was found in northern China (Henan Province). Bacitracin, multidrug, aminoglycoside, sulfonamide, and beta-lactam resistance genes were dominant in drinking water. Of the drinking water samples tested, 84% had a higher ARG abundance than typical environmental ecosystems of sediment and soil. Metagenomic assembly-based host-tracking analysis identified Acidovorax, Acinetobacter, Aeromonas, Methylobacterium, Methyloversatilis, Mycobacterium, Polaromonas, and Pseudomonas as the hosts of ARGs. Moreover, potential horizontal transfer of ARGs in drinking water systems was proposed by network and Procrustes analyses. The antibiotic resistome catalogue compiled using a large-scale survey provides a useful reference for future studies on the global surveillance and risk management of ARGs in drinking water. .

  5. Modulation of virulence and antibiotic susceptibility of enteropathogenic Escherichia coli strains by Enterococcus faecium probiotic strain culture fractions.

    Science.gov (United States)

    Ditu, Lia-Mara; Chifiriuc, Mariana Carmen; Bezirtzoglou, Eugenia; Voltsi, Chrysa; Bleotu, Coralia; Pelinescu, Diana; Mihaescu, Grigore; Lazar, Veronica

    2011-12-01

    The increasing rate of antimicrobial resistance drastically reduced the efficiency of conventional antibiotics and led to the reconsideration of the interspecies interactions in influencing bacterial virulence and response to therapy. The aim of the study was the investigation of the influence of the soluble and cellular fractions of Enterococcus (E.) faecium CMGB16 probiotic culture on the virulence and antibiotic resistance markers expression in clinical enteropathogenic Escherichia (E.) coli strains. The 7 clinical enteropathogenic E. coli strains, one standard E. coli ATCC 25,922 and one Bacillus (B.) cereus strains were cultivated in nutrient broth, aerobically at 37 °C, for 24 h. The E. faecium CMGB16 probiotic strain was cultivated in anaerobic conditions, at 37 °C in MRS (Man Rogosa Sharpe) broth, and co-cultivated with two pathogenic strains (B. cereus and E. coli O28) culture fractions (supernatant, washed sediment and heat-inactivated culture) for 6 h, at 37 °C. After co-cultivation, the soluble and cellular fractions of the probiotic strain cultivated in the presence of two pathogenic strains were separated by centrifugation (6000 rpm, 10 min), heat-inactivated (15 min, 100 °C) and co-cultivated with the clinical enteropathogenic E. coli strains in McConkey broth, for 24 h, at 37 °C, in order to investigate the influence of the probiotic fractions on the adherence capacity and antibiotic susceptibility. All tested probiotic combinations influenced the adherence pattern of E. coli tested strains. The enteropathogenic E. coli strains susceptibility to aminoglycosides, beta-lactams and quinolones was increased by all probiotic combinations and decreased for amoxicillin-clavulanic acid. This study demonstrates that the plurifactorial anti-infective action of probiotics is also due to the modulation of virulence factors and antibiotic susceptibility expression in E. coli pathogenic strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Determination of 21 antibiotics in sea cucumber using accelerated solvent extraction with in-cell clean-up coupled to ultra-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Zhu, Minghua; Zhao, Hongxia; Xia, Deming; Du, Juan; Xie, Huaijun; Chen, Jingwen

    2018-08-30

    An accelerated solvent extraction (ASE) with in-cell clean-up method coupled to ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to determine 21 antibiotics in sea cucumber. The analytes include 10 sulfonamides, 4 fluoroquinolones, 3 amphenicols, 2 beta-lactams, 1 lincosamide and trimethoprim. Optimal parameters of ASE method were obtained at 80 °C, 1 static cycle of 5 min with methanol/acetonitrile (1/1, v/v) using 2 g of C18 as adsorbent. Recoveries at 50.1-129.2% were achieved with RSD under 20%. Method detection limits ranged from 0.03 to 2.9 μg kg -1 . Compared to the reported ultrasound-assisted extraction method, the proposed method offered comparable extraction efficiency for sulfonamides from sea cucumber, but higher for other categories of antibiotics. This validated method was then successfully applied to sea cucumber samples and 9 antibiotics were detected with the highest concentration up to 57.7 μg kg -1 for norfloxacin. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Sensitivity analysis

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003741.htm Sensitivity analysis To use the sharing features on this page, please enable JavaScript. Sensitivity analysis determines the effectiveness of antibiotics against microorganisms (germs) ...

  8. High-throughput profiling of antibiotic resistance genes in drinking water treatment plants and distribution systems.

    Science.gov (United States)

    Xu, Like; Ouyang, Weiying; Qian, Yanyun; Su, Chao; Su, Jianqiang; Chen, Hong

    2016-06-01

    Antibiotic resistance genes (ARGs) are present in surface water and often cannot be completely eliminated by drinking water treatment plants (DWTPs). Improper elimination of the ARG-harboring microorganisms contaminates the water supply and would lead to animal and human disease. Therefore, it is of utmost importance to determine the most effective ways by which DWTPs can eliminate ARGs. Here, we tested water samples from two DWTPs and distribution systems and detected the presence of 285 ARGs, 8 transposases, and intI-1 by utilizing high-throughput qPCR. The prevalence of ARGs differed in the two DWTPs, one of which employed conventional water treatments while the other had advanced treatment processes. The relative abundance of ARGs increased significantly after the treatment with biological activated carbon (BAC), raising the number of detected ARGs from 76 to 150. Furthermore, the final chlorination step enhanced the relative abundance of ARGs in the finished water generated from both DWTPs. The total enrichment of ARGs varied from 6.4-to 109.2-fold in tap water compared to finished water, among which beta-lactam resistance genes displayed the highest enrichment. Six transposase genes were detected in tap water samples, with the transposase gene TnpA-04 showing the greatest enrichment (up to 124.9-fold). We observed significant positive correlations between ARGs and mobile genetic elements (MGEs) during the distribution systems, indicating that transposases and intI-1 may contribute to antibiotic resistance in drinking water. To our knowledge, this is the first study to investigate the diversity and abundance of ARGs in drinking water treatment systems utilizing high-throughput qPCR techniques in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Occurrence of transferable antibiotic resistances in commercialized ready-to-eat mealworms (Tenebrio molitor L.).

    Science.gov (United States)

    Osimani, Andrea; Cardinali, Federica; Aquilanti, Lucia; Garofalo, Cristiana; Roncolini, Andrea; Milanović, Vesna; Pasquini, Marina; Tavoletti, Stefano; Clementi, Francesca

    2017-12-18

    The present study aimed to assess the occurrence of transferable determinants conferring resistance to tetracyclines, macrolide-lincosamide-streptogramin B, vancomycin, beta-lactams, and aminoglycosides in 40 samples of commercialized edible mealworms (Tenebrio molitor L.) purchased from European Union (EU) and non-EU producers. A high prevalence of tet(K) was observed in all of the samples assayed, with percentages of PCR-based positivity that ranged from 80% (samples from Thailand) to 100% (samples from the Netherlands, Belgium and France). For macrolides, erm(B) prevailed, being detected in 57.5% of the samples assayed, whereas erm(A) and erm(C) were detected with lower frequencies. Genes for resistance to vancomycin were only detected in samples produced in France and Belgium, with 90% and 10% of the samples being positive for vanA, respectively. Beta-lactamase genes were found with low occurrence, whereas the gene aac-aph, conferring high resistance to aminoglycosides, was found in 40% of the samples produced in the Netherlands and Belgium and 20% of the samples produced in Thailand. The results of Principal Coordinate Analysis and Principal Component Analysis depicted a clean separation of the samples collected from the four producers based on the distribution of the 12 AR determinants considered. Given the growing interest on the use of mealworms as a novel protein source, AR detection frequencies found in the present study suggest further investigation into the use of antibiotics during rearing of this insect species and more extensive studies focused on the factors that can affect the diffusion of transferable ARs in the production chain. Until such studies are completed, prudent use of antibiotics during rearing of edible insects is recommended. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The In-Feed Antibiotic Carbadox Induces Phage Gene Transcription in the Swine Gut Microbiome

    Directory of Open Access Journals (Sweden)

    Timothy A. Johnson

    2017-08-01

    Full Text Available Carbadox is a quinoxaline-di-N-oxide antibiotic fed to over 40% of young pigs in the United States that has been shown to induce phage DNA transduction in vitro; however, the effects of carbadox on swine microbiome functions are poorly understood. We investigated the in vivo longitudinal effects of carbadox on swine gut microbial gene expression (fecal metatranscriptome and phage population dynamics (fecal dsDNA viromes. Microbial metagenome, transcriptome, and virome sequences were annotated for taxonomic inference and gene function by using FIGfam (isofunctional homolog sequences and SEED subsystems databases. When the beta diversities of microbial FIGfam annotations were compared, the control and carbadox communities were distinct 2 days after carbadox introduction. This effect was driven by carbadox-associated lower expression of FIGfams (n = 66 related to microbial respiration, carbohydrate utilization, and RNA metabolism (q < 0.1, suggesting bacteriostatic or bactericidal effects within certain populations. Interestingly, carbadox treatment caused greater expression of FIGfams related to all stages of the phage lytic cycle 2 days following the introduction of carbadox (q ≤0.07, suggesting the carbadox-mediated induction of prophages and phage DNA recombination. These effects were diminished by 7 days of continuous carbadox in the feed, suggesting an acute impact. Additionally, the viromes included a few genes that encoded resistance to tetracycline, aminoglycoside, and beta-lactam antibiotics but these did not change in frequency over time or with treatment. The results show decreased bacterial growth and metabolism, prophage induction, and potential transduction of bacterial fitness genes in swine gut bacterial communities as a result of carbadox administration.

  11. The In-Feed Antibiotic Carbadox Induces Phage Gene Transcription in the Swine Gut Microbiome

    Science.gov (United States)

    Johnson, Timothy A.; Severin, Andrew J.; Bayles, Darrell O.; Nasko, Daniel J.; Wommack, K. Eric; Howe, Adina

    2017-01-01

    ABSTRACT Carbadox is a quinoxaline-di-N-oxide antibiotic fed to over 40% of young pigs in the United States that has been shown to induce phage DNA transduction in vitro; however, the effects of carbadox on swine microbiome functions are poorly understood. We investigated the in vivo longitudinal effects of carbadox on swine gut microbial gene expression (fecal metatranscriptome) and phage population dynamics (fecal dsDNA viromes). Microbial metagenome, transcriptome, and virome sequences were annotated for taxonomic inference and gene function by using FIGfam (isofunctional homolog sequences) and SEED subsystems databases. When the beta diversities of microbial FIGfam annotations were compared, the control and carbadox communities were distinct 2 days after carbadox introduction. This effect was driven by carbadox-associated lower expression of FIGfams (n = 66) related to microbial respiration, carbohydrate utilization, and RNA metabolism (q < 0.1), suggesting bacteriostatic or bactericidal effects within certain populations. Interestingly, carbadox treatment caused greater expression of FIGfams related to all stages of the phage lytic cycle 2 days following the introduction of carbadox (q ≤0.07), suggesting the carbadox-mediated induction of prophages and phage DNA recombination. These effects were diminished by 7 days of continuous carbadox in the feed, suggesting an acute impact. Additionally, the viromes included a few genes that encoded resistance to tetracycline, aminoglycoside, and beta-lactam antibiotics but these did not change in frequency over time or with treatment. The results show decreased bacterial growth and metabolism, prophage induction, and potential transduction of bacterial fitness genes in swine gut bacterial communities as a result of carbadox administration. PMID:28790203

  12. Assessment of antibiotic susceptibilities, genotypic characteristics ...

    African Journals Online (AJOL)

    Jane

    2011-09-28

    Sep 28, 2011 ... Staphylococcus aureus and Salmonella Typhimurium ... This study was designed to evaluate the antibiotic susceptibilities, genotypic characteristics and ..... Distribution of reference and virulence genes among antibiotic-sensitive S. aureus (SAS), .... environmental factors such as temperature, water activity,.

  13. Monitoring and evaluation of antibiotic resistance genes in four municipal wastewater treatment plants in Harbin, Northeast China

    International Nuclear Information System (INIS)

    Wen, Qinxue; Yang, Lian; Duan, Ruan; Chen, Zhiqiang

    2016-01-01

    The development and proliferation of antibiotic resistance in pathogenic and environmental microorganisms is of great concern for public health. In this study, the distribution and removal efficiency of intI1 and eight subtypes of antibiotic resistance genes (ARGs) for tetracycline, sulfonamides, beta-lactams resistance in four municipal wastewater treatment plants (WWTPs) in Harbin, which locates in Songhua River basin in cold areas of China, were monitored by real-time fluorescent quantitative PCR. The results showed that intI1 and 6 ARGs except for bla_T_E_M and bla_S_H_V were detected in wastewater and sludge samples and 0.3–2.7 orders of magnitude of ARGs removal efficiency in the four WWTPs were observed. The investigation on the removal of ARGs of different treatment units in one WWTP showed that the biological treatment unit played the most important role in ARGs removal (1.2–1.8 orders of magnitude), followed by UV disinfection, while primary physical treatment units can hardly remove any ARGs. Although all the WWTPs can remove ARGs effectively, ARGs concentrations are still relatively high in the effluent, their further attenuation should be investigated. - Highlights: • The distribution of 8 ARGs and intI1 in WWTPs in Harbin in winter were monitored. • ARGs removal in 4 WWTPs with different processes were investigated. • Biological treatment process plays the most important role in ARGs removal. • A relatively high level of ARGs is still present in the effluent after wastewater treatment. • Regional uses of antibiotics other than season temperature affects the fate of ARGs in WWTPs.

  14. Determination of fluoroquinolone antibiotics by microchip capillary electrophoresis along with time-resolved sensitized luminescence of their terbium(III) complexes

    International Nuclear Information System (INIS)

    Sierra-Rodero, Marina; Fernández -Romero, Juan Manuel; Gómez -Hens, Agustina

    2014-01-01

    We report on the time-resolved detection of the three fluoroquinolone (FQs) antibiotics ciprofloxacin (CIP), enrofloxacin (ENR) and flumequine (FLU). On addition of terbium(III) ions, the terbium(III)-FQs chelates are formed in-situ in an on-capillary derivatization reaction of a microfluidic system. The laser-induced terbium(III)-sensitized luminescence of the chelates is measured at excitation/emission wavelengths of 337/545 nm. The analytes can be separated and quantified within less than 4 min. A solid phase extraction step for analyte preconcentration can be included prior to chelation and microchip capillary electrophoresis. The analytical ranges of the calibration graphs for CIP, ENR and FLU are from 10.6 to 60.0, 10.3 to 51.0, and 11.5 to 58.8 ng mL −1 , respectively, and the detection limits are 3.2, 3.1 and 3.6 ng mL −1 , respectively. The precision was established at two concentration levels of each analyte and revealed relative standard deviations in the range from 3.0 to 10.2 %. The method was applied to the analysis of FQ-spiked water samples. (author)

  15. Early life exposure to antibiotics and the subsequent development of eczema, wheeze, and allergic sensitization in the first 2 years of life: the KOALA Birth Cohort Study

    NARCIS (Netherlands)

    Kummeling, Ischa; Stelma, Foekje F.; Dagnelie, Pieter C.; Snijders, Bianca E. P.; Penders, John; Huber, Machteld; van Ree, Ronald; van den Brandt, Piet A.

    2007-01-01

    OBJECTIVES: Antibiotic exposure in early life may be associated with atopic disease development either by interfering with bacterial commensal flora or by modifying the course of bacterial infections. We evaluated early life exposure to antibiotics and the subsequent development of eczema, wheeze,

  16. Uncomplicated E Coli Urinary Tract Infection in College Women: A Follow-Up Study of E Coli Sensitivities to Commonly Prescribed Antibiotics

    Science.gov (United States)

    Ansbach, Robert K.; Dybus, Karen; Bergeson, Rachel

    2005-01-01

    Treatment of uncomplicated urinary tract infections (UTIs) has changed in the past few years with researchers advocating empiric treatment for shorter periods of time without the use of cultures. Researchers report that antibiotic resistance of Escherichia coli (E coli) to commonly prescribed antibiotics in uncomplicated UTIs has been increasing.…

  17. Rapid and Sensitive Detection of Bacteria Response to Antibiotics Using Nanoporous Membrane and Graphene Quantum Dot (GQDs-Based Electrochemical Biosensors

    Directory of Open Access Journals (Sweden)

    Weiwei Ye

    2017-05-01

    Full Text Available The wide abuse of antibiotics has accelerated bacterial multiresistance, which means there is a need to develop tools for rapid detection and characterization of bacterial response to antibiotics in the management of infections. In the study, an electrochemical biosensor based on nanoporous alumina membrane and graphene quantum dots (GQDs was developed for bacterial response to antibiotics detection. Anti-Salmonella antibody was conjugated with amino-modified GQDs by glutaraldehyde and immobilized on silanized nanoporous alumina membranes for Salmonella bacteria capture. The impedance signals across nanoporous membranes could monitor the capture of bacteria on nanoporous membranes as well as bacterial response to antibiotics. This nanoporous membrane and GQD-based electrochemical biosensor achieved rapid detection of bacterial response to antibiotics within 30 min, and the detection limit could reach the pM level. It was capable of investigating the response of bacteria exposed to antibiotics much more rapidly and conveniently than traditional tools. The capability of studying the dynamic effects of antibiotics on bacteria has potential applications in the field of monitoring disease therapy, detecting comprehensive food safety hazards and even life in hostile environment.

  18. Forgotten antibiotics

    DEFF Research Database (Denmark)

    Pulcini, Céline; Bush, Karen; Craig, William A

    2012-01-01

    In view of the alarming spread of antimicrobial resistance in the absence of new antibiotics, this study aimed at assessing the availability of potentially useful older antibiotics. A survey was performed in 38 countries among experts including hospital pharmacists, microbiologists, and infectious...

  19. bacterial flora and antibiotic sensitivity

    African Journals Online (AJOL)

    Purulent pelvic collections are common pathologies observed in contemporary gynaecological practice. They may originate from chronic pelvic inflammatory disease, from abortions or following normal deliveries. This study was designed to compare the bacterial flora in purulent pelvic collections obtained from HIV infected ...

  20. Loop-mediated isothermal amplification: Rapid and sensitive detection of the antibiotic resistance gene ISAba1-blaOXA-51-like in Acinetobacter baumannii.

    Science.gov (United States)

    Mu, Xiaoqin; Nakano, Ryuichi; Nakano, Akiyo; Ubagai, Tsuneyuki; Kikuchi-Ueda, Takane; Tansho-Nagakawa, Shigeru; Kikuchi, Hirotoshi; Kamoshida, Go; Endo, Shiro; Yano, Hisakazu; Ono, Yasuo

    2016-02-01

    Carbapenem-resistant Acinetobacter baumannii, which are mainly induced by the production of OXA-type β-lactamases, are among the leading causes of nosocomial infections worldwide. Among the β-lactamase genes, the presence of the OXA-51-like gene carrying the upstream insertion sequence, ISAba1, was found to be one of the most prevalent carbapenem resistance mechanisms utilized by these bacteria. Consequently, it is necessary to develop a rapid detection method for ISAba1-blaOXA-51-like sequence for the timely and appropriate antibiotic treatment of A. baumannii infection. In this study, a loop-mediated isothermal amplification (LAMP) assay was optimized for ISAba1-blaOXA-51-like detection. The LAMP primer set was designed to recognize distinct sequences in the ISAba1-blaOXA-51-like gene and could amplify the gene within 25 min at an isothermal temperature of 60°C. This LAMP assay was able to detect the ISAba1-blaOXA-51-like gene with high specificity; in addition, no cross-reactivity was observed for other types of β-lactamase producers (OXA-23-like, OXA-40-like, OXA-58-like, and IMP-1), as indicated by the absence of false positive or false negative results. The detection limit for this assay was found to be 10(0)CFU per tube which was 100-fold more sensitive than a polymerase chain reaction assay for ISAba1-blaOXA-51-like detection. Furthermore, the LAMP assay provided swift detection of the ISAba1-blaOXA-51-like gene, even directly from clinical specimens. In summary, we have described a new, rapid assay for the detection of the ISAba1-blaOXA-51-like gene from A. baumannii that could be useful in a clinical setting. This method might facilitate epidemiological studies and allow monitoring of the emergence of drug resistant strains. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Degradation of 2,4-dichlorophenoxyacetic acid by a halotolerant strain of Penicillium chrysogenum: antibiotic production.

    Science.gov (United States)

    Ferreira-Guedes, Sumaya; Mendes, Benilde; Leitão, Ana Lúcia

    2012-01-01

    The extensive use of pesticides in agriculture has prompted intensive research on chemical and biological methods in order to protect contamination of water and soil resources. In this paper the degradation of the pesticide 2,4-dichlorophenoxyacetic acid by a Penicillium chrysogenum strain previously isolated from a salt mine was studied in batch cultures. Co-degradation of 2,4-dichlorophenoxyacetic acid with additives such as sugar and intermediates of pesticide metabolism was also investigated. Penicillium chrysogenum in solid medium was able to grow at concentrations up to 1000 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D) with sucrose. Meanwhile, supplementation of the solid medium with glucose and lactose led to fungal growth at concentrations up to 500 mg/L of herbicide. Batch cultures of 2,4-D at 100 mg/L were developed under aerobic conditions with the addition of glucose, lactose and sucrose, showing sucrose as the best additional carbon source. The 2,4-D removal was quantified by liquid chromatography. The fungus was able to use 2,4-D as the sole carbon and energy source under 0%, 2% and 5.9% NaCl. The greatest 2,4-D degradation efficiency was found using alpha-ketoglutarate and ascorbic acid as co-substrates under 2% NaCl at pH 7. Penicillin production was evaluated in submerged cultures by bioassay, and higher amounts of beta-lactam antibiotic were produced when the herbicide was alone. Taking into account the ability of P. chrysogenum CLONA2 to degrade aromatic compounds, this strain could be an interesting tool for 2,4-D herbicide remediation in saline environments.

  2. Detection of antibiotic resistance genes in samples from acute and chronic endodontic infections and after treatment.

    Science.gov (United States)

    Rôças, Isabela N; Siqueira, José F

    2013-09-01

    The purpose of this study was twofold: survey samples from acute and chronic endodontic infections for the presence of genes encoding resistance to beta-lactams, tetracycline and erythromycin, and evaluate the ability of treatment to eliminate these genes from root canals. DNA extracts from samples of abscess aspirates (n=25) and root canals of teeth with asymptomatic apical periodontitis (n=24) were used as template for direct detection of the genes blaTEM, cfxA, tetM, tetQ, tetW, and ermC using real-time polymerase chain reaction (PCR). Bacterial presence was determined using PCR with universal bacterial primers. Root canals of the asymptomatic cases were also sampled and evaluated after chemomechanical procedures using NiTi instruments with 2.5% NaOCl irrigation. All abscess and initial root canal samples were positive for bacteria. At least one of the target resistance genes was found in 36% of the abscess samples and 67% of the asymptomatic cases. The most prevalent genes in abscesses were blaTEM (24%) and ermC (24%), while tetM (42%) and tetW (29%) prevailed in asymptomatic cases. The blaTEM gene was significantly associated with acute cases (p=0.02). Conversely, tetM was significantly more prevalent in asymptomatic cases (p=0.008). Treatment eliminated resistance genes from most cases. Acute and chronic endodontic infections harboured resistance genes for 3 classes of widely used antibiotics. In most cases, treatment was effective in eliminating these genes, but there were a few cases in which they persisted. The implications of persistence are unknown. Direct detection of resistance genes in abscesses may be a potential method for rapid diagnosis and establishment of proactive antimicrobial therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Prolonged suppressive antibiotic therapy for prosthetic joint infection in the elderly: a national multicentre cohort study.

    Science.gov (United States)

    Prendki, V; Ferry, T; Sergent, P; Oziol, E; Forestier, E; Fraisse, T; Tounes, S; Ansart, S; Gaillat, J; Bayle, S; Ruyer, O; Borlot, F; Le Falher, G; Simorre, B; Dauchy, F-A; Greffe, S; Bauer, T; Bell, E N; Martha, B; Martinot, M; Froidure, M; Buisson, M; Waldner, A; Lemaire, X; Bosseray, A; Maillet, M; Charvet, V; Barrelet, A; Wyplosz, B; Noaillon, M; Denes, E; Beretti, E; Berlioz-Thibal, M; Meyssonnier, V; Fourniols, E; Tliba, L; Eden, A; Jean, M; Arvieux, C; Guignery-Kadri, K; Ronde-Oustau, C; Hansmann, Y; Belkacem, A; Bouchand, F; Gavazzi, G; Herrmann, F; Stirnemann, J; Dinh, A

    2017-09-01

    During prosthetic joint infection (PJI), optimal surgical management with exchange of the device is sometimes impossible, especially in the elderly population. Thus, prolonged suppressive antibiotic therapy (PSAT) is the only option to prevent acute sepsis, but little is known about this strategy. We aimed to describe the characteristics, outcome and tolerance of PSAT in elderly patients with PJI. We performed a national cross-sectional cohort study of patients >75 years old and treated with PSAT for PJI. We evaluated the occurrence of events, which were defined as: (i) local or systemic progression of the infection (failure), (ii) death and (iii) discontinuation or switch of PSAT. A total of 136 patients were included, with a median age of 83 years [interquartile range (IQR) 81-88]. The predominant pathogen involved was Staphylococcus (62.1%) (Staphylococcus aureus in 41.7%). A single antimicrobial drug was prescribed in 96 cases (70.6%). There were 46 (33.8%) patients with an event: 25 (18%) with an adverse drug reaction leading to definitive discontinuation or switch of PSAT, 8 (5.9%) with progression of sepsis and 13 died (9.6%). Among patients under follow-up, the survival rate without an event at 2 years was 61% [95% confidence interval (CI): 51;74]. In the multivariate Cox analysis, patients with higher World Health Organization (WHO) score had an increased risk of an event [hazard ratio (HR) = 1.5, p = 0.014], whereas patients treated with beta-lactams are associated with less risk of events occurring (HR = 0.5, p = 0.048). In our cohort, PSAT could be an effective and safe option for PJI in the elderly.

  4. Antibiotic sensitivity of bacterial strains isolated from newborn infants Sensibilidad a los antibióticos de bacterias aisladas de neonatos hospitalizados

    Directory of Open Access Journals (Sweden)

    Alvaro Uribe

    1990-02-01

    Full Text Available

    Eighty nine bacterial strains isolated from newborn infants hospitalized at a Special Care Unit in Medellin, Colombia, were studied. The sensitivity of each one was determined by the Minimallnhibitory Concentration method against 21 antibiotics; a high frequency of resistance was found toward gentamycin, netilmycin, oxacillin, penicillin G and ampicillin, that are often employed as initial therapy in newborn infants; on the other hand both Gram positive and Gram negative bacteria exhibited high percentages of sensitivity against quinolones; aztreonam and third generation cephalosporins were also highly effective against Gram negative bacilli. On the basis of this new information the need to restate therapeutic conducts in the case of serious bacterial neonatal infections is emphasized.

    Se estudiaron 89 cepas bacterianas aisladas de neonatos hospitalizados en la sala de cuidados especiales de la Fundación Hospitalaria San Vicente de Paúl, de Medellín; a cada una se le determinó la sensibilidad frente a 21 antibióticos por el método de la concentración inhibitoria mínima (CIM; se halló una alta frecuencia de resistencia hacia la gentamicina, la netilmicina, la oxacilina y la ampicilina que se usan a menudo en esta institución como terapia inicial en las infecciones del recién nacido; por otra parte se demostraron altos porcentajes de sensibilidad hacia las quinolonas tanto de las bacterias gram positivas como de las gram negativas; contra estas últimas también fueron muy efectivos el aztreonam y las cefalosporinas de tercera generación. A la luz de esta nueva información se llama la atención hacia la necesidad de revaluar las normas de la antibioterapia en las infecciones graves del recién nacido.

  5. Correlation of Frequency of Pseudomonas Aeruginosa and Exos & Exou Genes and Their Antibiotic Sensitivity Pattern in Specimen Isolated from ICU Ward

    Directory of Open Access Journals (Sweden)

    Mahsa Joodzadeh

    2016-06-01

    Full Text Available Pseudomonas aeruginosa is a cause of nosocomial infections that can be destroyer by antibiotic-resistant strains. This study conducted to determine the antibiotic susceptibility pattern and distribution of exoU and exoS among clinical isolates of P. aeruginosa. Fifty three specimens of tracheal tube were collected from patients who were hospitalized in ICU wards and P. aeruginosa were isolated and identified by phenotypic and molecular methods. Antibiotic resistance performs by disk diffusion and analyzed their virulence factors genes by PCR method. Susceptibility pattern of 53 isolates of P. aeruginosa showed that majority and minority of resistance belong to cefepime (55.4%,and Meropenem (50% Respectively. Twenty four (45.2% isolates were not susceptible to three or more different groups of antibiotics. Forty (71.4% of isolated have had exoSand1(1.8% exoU, 8(15%both of exoS and exoU and the rest being negative for exoS or exoU. Distribution of MDR(resistance to three or more group of antibiotics exoenzymes were shown: exoU(7.5%and exoS(90.5%. According to statistically analysis there were not significant relationship between presence of exo SandexoU and antibiotic resistance.

  6. Antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Marianne Frieri

    2017-07-01

    Full Text Available Summary: Antimicrobial resistance in bacterial pathogens is a challenge that is associated with high morbidity and mortality. Multidrug resistance patterns in Gram-positive and -negative bacteria are difficult to treat and may even be untreatable with conventional antibiotics. There is currently a shortage of effective therapies, lack of successful prevention measures, and only a few new antibiotics, which require development of novel treatment options and alternative antimicrobial therapies. Biofilms are involved in multidrug resistance and can present challenges for infection control. Virulence, Staphylococcus aureus, Clostridium difficile infection, vancomycin-resistant enterococci, and control in the Emergency Department are also discussed. Keywords: Antibiotic resistance, Biofilms, Infections, Public health, Emergency Department

  7. Empiric antibiotic therapy in urinary tract infection in patients with risk factors for antibiotic resistance in a German emergency department.

    Science.gov (United States)

    Bischoff, Sebastian; Walter, Thomas; Gerigk, Marlis; Ebert, Matthias; Vogelmann, Roger

    2018-01-26

    The aim of this study was to identify clinical risk factors for antimicrobial resistances and multidrug resistance (MDR) in urinary tract infections (UTI) in an emergency department in order to improve empirical therapy. UTI cases from an emergency department (ED) during January 2013 and June 2015 were analyzed. Differences between patients with and without resistances towards Ciprofloxacin, Piperacillin with Tazobactam (Pip/taz), Gentamicin, Cefuroxime, Cefpodoxime and Ceftazidime were analyzed with Fisher's exact tests. Results were used to identify risk factors with logistic regression modelling. Susceptibility rates were analyzed in relation to risk factors. One hundred thirty-seven of four hundred sixty-nine patients who met the criteria of UTI had a positive urine culture. An MDR pathogen was found in 36.5% of these. Overall susceptibility was less than 85% for standard antimicrobial agents. Logistic regression identified residence in nursing homes, male gender, hospitalization within the last 30 days, renal transplantation, antibiotic treatment within the last 30 days, indwelling urinary catheter and recurrent UTI as risk factors for MDR or any of these resistances. For patients with no risk factors Ciprofloxacin had 90%, Pip/taz 88%, Gentamicin 95%, Cefuroxime 98%, Cefpodoxime 98% and Ceftazidime 100% susceptibility. For patients with 1 risk factor Ciprofloxacin had 80%, Pip/taz 80%, Gentamicin 88%, Cefuroxime 78%, Cefpodoxime 78% and Ceftazidime 83% susceptibility. For 2 or more risk factors Ciprofloxacin drops its susceptibility to 52%, Cefuroxime to 54% and Cefpodoxime to 61%. Pip/taz, Gentamicin and Ceftazidime remain at 75% and 77%, respectively. We identified several risk factors for resistances and MDR in UTI. Susceptibility towards antimicrobials depends on these risk factors. With no risk factor cephalosporins seem to be the best choice for empiric therapy, but in patients with risk factors the beta-lactam penicillin Piperacillin with Tazobactam

  8. Cefepime shows good efficacy and no antibiotic resistance in pneumonia caused by Serratia marcescens and Proteus mirabilis - an observational study.

    Science.gov (United States)

    Yayan, Josef; Ghebremedhin, Beniam; Rasche, Kurt

    2016-03-23

    Many antibiotics have no effect on Gram-positive and Gram-negative microbes, which necessitates the prescription of broad-spectrum antimicrobial agents that can lead to increased risk of antibiotic resistance. These pathogens constitute a further threat because they are also resistant to numerous beta-lactam antibiotics, as well as other antibiotic groups. This study retrospectively investigates antimicrobial resistance in hospitalized patients suffering from pneumonia triggered by Gram-negative Serratia marcescens or Proteus mirabilis. The demographic and clinical data analyzed in this study were obtained from the clinical databank of the HELIOS Clinic, Witten/Herdecke University, Wuppertal, Germany, for inpatients presenting with pneumonia triggered by S. marcescens or P. mirabilis from 2004 to 2014. An antibiogram was conducted for the antibiotics utilized as part of the management of patients with pneumonia triggered by these two pathogens. Pneumonia was caused by Gram-negative bacteria in 115 patients during the study period from January 1, 2004, to August 12, 2014. Of these, 43 (37.4 %) hospitalized patients [26 males (60.5 %, 95 % CI 45.9 %-75.1 %) and 17 females (39.5 %, 95 % CI 24.9 %-54.1 %)] with mean age of 66.2 ± 13.4 years had pneumonia triggered by S. marcescens, while 20 (17.4 %) patients [14 males (70 %, 95 % CI 49.9 %-90.1 %) and 6 females (30 %, 95 % CI 9.9 %-50.1 %)] with a mean age of 64.6 ± 12.8 years had pneumonia caused by P. mirabilis. S. marcescens showed an increased antibiotic resistance to ampicillin (100 %), ampicillin-sulbactam (100 %), and cefuroxime (100 %). P. mirabilis had a high resistance to tetracycline (100 %) and ampicillin (55 %). S. marcescens (P < 0.0001) and P. mirabilis (P = 0.0003) demonstrated no resistance to cefepime in these patients with pneumonia. S. marcescens and P. mirabilis were resistant to several commonly used antimicrobial agents, but showed no resistance to

  9. Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran.

    Science.gov (United States)

    Mortazavi, Seyed Mohammad Javad; Zarei, Samira; Taheri, Mohammad; Tajbakhsh, Saeed; Mortazavi, Seyed Alireza; Ranjbar, Sahar; Momeni, Fatemeh; Masoomi, Samaneh; Ansari, Leila; Movahedi, Mohammad Mehdi; Taeb, Shahram; Zarei, Sina; Haghani, Masood

    2017-04-01

    Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium ( S. typhimurium ), Staphylococcus aureus , and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

  10. Sensitivity to Antibiotics of Bacteria Exposed to Gamma Radiation Emitted from Hot Soils of the High Background Radiation Areas of Ramsar, Northern Iran

    Directory of Open Access Journals (Sweden)

    Seyed Mohammad Javad Mortazavi

    2017-04-01

    Full Text Available Background: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. Objective: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium, Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. Methods: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. Results: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6 mm; it was 14.7 (SD 0.6 mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. Conclusion: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.

  11. Comparative study of isolates from community-acquired and catheter-associated urinary tract infections with reference to biofilm-producing property, antibiotic sensitivity and multi-drug resistance.

    Science.gov (United States)

    Bardoloi, Vishwajeet; Yogeesha Babu, K V

    2017-07-01

    Urinary tract infection (UTI) can be community-acquired (Com-UTI) or catheter-associated (CAUTI) and may be associated with biofilm-producing organisms. A comparative analysis of biofilm-producing property (BPP), antibiotic-sensitivity and multi-drug resistance (MDR) and their relation with the BPP of isolates from Com-UTI and CAUTI has not yet been performed and necessitated this study. (1) isolation of bacteria from CAUTI and Com-UTI and identification of their BPP, antibiotic-sensitivity and MDR status; (2) comparison of the isolates from CAUTI and Com-UTI as regards BPP, MDR status and their relation with BPP. isolates from 100 cases each of Com-UTI and CAUTI were subjected to Congo redagar (CRA) and Safranin tube tests. Antibiotic susceptibility was investigated using the disc diffusion method. Both groups were compared regarding BPP, drug sensitivity and MDR status. Statistical analyses were performed using χ2 and Fisher's exact tests. 76.19 % of isolates from Com-UTI and 60.72 % from CAUTI had BPP (P=0.0252; significant). The Safranin tube test detected more isolates with BPP than the CRA test. MDR is greater in CAUTI than Com-UTI (83.33 % versus 64.76 %; P=0.0039; significant). MDR is greater in isolates with BPP in both Com-UTI and CAUTI (76.47 and 62.35 %; non-significant). BPP was found in both Com-UTI and CAUTI. When used together, the Safranin tube test and the CRA test increased the sensitivity of detecting BPP. MDR was higher in CAUTI than Com-UTI. MDR and BPP are not interrelated or associated, especially in settings where it is not certain that isolates were obtained from a well-formed biofilm. However, this does not rule out a higher incidence or prevalence of MDR in isolates with BPP taken directly from the biofilms.

  12. Subinhibitory concentrations of antibiotics affect stress and virulence gene expression in Listeria monocytogenes and cause enhanced stress sensitivity but do not affect Caco‐2 cell invasion

    DEFF Research Database (Denmark)

    Knudsen, Gitte Maegaard; Holch, Anne; Gram, Lone

    2012-01-01

    with promoter fusions, 14 of 16 antibiotics induced or repressed expression of one or more stress and/or virulence genes. Despite ampicillin‐induced up‐regulation of PinlA‐lacZ expression, Caco‐2 cell invasion was not affected. Subinhibitory concentrations of ampicillin and tetracycline caused up‐ and down...

  13. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Munck, Christian

    morbidity and mortality as well as an increase in the cost of treatment. Understanding how bacteria respond to antibiotic exposure gives the foundations for a rational approach to counteract antimicrobial resistance. In the work presented in this thesis, I explore the two fundamental sources...... of antimicrobial resistance: (1) adaptive mutations and (2) horizontal acquisition of resistance genes from antibiotic gene reservoirs. By studying the geno- and phenotypic changes of E. coli in response to single and drug-pair exposures, I uncover the evolutionary trajectories leading to adaptive resistance. I...... to rationally design drug combinations that limit the evolution of antibiotic resistance due to counteracting evolutionary trajectories. My results highlight that an in-depth knowledge about the genetic responses to the individual antimicrobial compounds enables the prediction of responses to drug combinations...

  14. Resistance to oral antibiotics in 4569 Gram-negative rods isolated from urinary tract infection in children.

    Science.gov (United States)

    Calzi, Anna; Grignolo, Sara; Caviglia, Ilaria; Calevo, Maria Grazia; Losurdo, Giuseppe; Piaggio, Giorgio; Bandettini, Roberto; Castagnola, Elio

    2016-09-01

    To investigate antibiotic resistance among pathogens isolated from urines in a tertiary care children's hospital in Italy. Retrospective analysis of prospectively collected data on antibiotic susceptibility of Gram-negatives isolated from urines at the Istituto Giannina Gaslini, Genoa - Italy from 2007 to 2014. Antibiotic susceptibility was evaluated. By means of CLSI criteria from 2007 to 2010, while from 2011 EUCAST criteria were adopted. Data on susceptibility to amoxicillin-clavulanate, co-trimoxazole, cefuroxime, nitrofurantoin, fosfomycin and ciprofloxacin were evaluated for Escherichia coli, while for other Enterobacteriaceae data were collected for amoxicillin-clavulanate, co-trimoxazole and ciprofloxacin and for ciprofloxacin against Pseudomonas aeruginosa. Univariate and multivariable analyses were performed for risk factors associated with resistance. A total of 4596 Gram-negative strains were observed in 3364 patients. A significant increase in the proportion of resistant strains was observed for E.coli against amoxicillin-clavulanate, cefuroxime and ciprofloxacin and for others Enterobacteriaceae against co-trimoxazole and ciprofloxacin. Resistance to nitrofurantoin and fosfomycin was very infrequent in E.coli. Logistic regression analysis showed that repeated episode of urinary tract infections was a risk factor for E.coli resistance to amoxicillin-clavulanate, co-trimoxazole and cefuroxime, while admission in one of the Units usually managing children with urinary tract malformations was significantly associated to resistance to amoxicillin-clavulanate and cefuroxime. In conclusion the present study shows an increase in antibiotic resistance in pediatric bacteria isolated from urines in children, especially in presence of repeated episodes and/or urinary tract malformations. This resistance is worrisome for beta-lactams and cotrimoxazole, and start to increase also for fluoroquinolones while nitrofurantoin and fosfomycin still could represent useful

  15. Removal of selected PPCPs, EDCs, and antibiotic resistance genes in landfill leachate by a full-scale constructed wetlands system.

    Science.gov (United States)

    Yi, Xinzhu; Tran, Ngoc Han; Yin, Tingru; He, Yiliang; Gin, Karina Yew-Hoong

    2017-09-15

    Landfill leachate could be a significant source of emerging contaminants (ECs) and antibiotic resistance genes (ARGs) into the environment. This study provides the first information on the occurrence of selected ECs and ARGs in raw leachate from 16-year old closed landfill site in Singapore. Among the investigated ECs, acetaminophen (ACT), bisphenol A (BPA), clofibric acid (CA), caffeine (CF), crotamiton (CTMT), diclofenac (DCF), N,N-diethyl-m-toluamide (DEET), gemfibrozil (GFZ), lincomycin (LIN), salicylic acid (SA), and sulfamethazine (SMZ) were the most frequently detected compounds in raw landfill leachate. The concentrations of detected ECs in raw landfill leachate varied significantly, from below quantification limit to 473,977 ng/L, depending on the compound. In this study, Class I integron (intl1) gene and ten ARGs were detected in raw landfill leachate. Sulfonamide resistance (sul1, sul2, and dfrA), aminoglycoside resistance (aac6), tetracycline resistance (tetO), quinolone resistance (qnrA), and intl1 were ubiquitously present in raw landfill leachate. Other resistance genes, such as beta-lactam resistance (blaNMD1, blaKPC, and blaCTX) and macrolide-lincosamide resistance (ermB) were also detected, detection frequency of 90%) in the investigated hybrid CW system. This hybrid CW system was also found to be effective in the reduction of several ARGs (intl1, sul1, sul2, and qnrA). Aeration lagoons and reed beds appeared to be the most important treatment units of the hybrid CW for removing the majority of ECs from the leachate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Combating Antibiotic Resistance

    Science.gov (United States)

    ... Bacteria Phasing Out Certain Antibiotic Use in Farm Animals FDA: Cutting-Edge Technology Sheds Light on Antibiotic Resistance For More Information Antibiotics and Antibiotic Resistance Antimicrobial Resistance Information for Consumers and Health Professionals CDC: ...

  17. Bacterial Contamination of Adult House Flies (Musca domestica) and Sensitivity of these Bacteria to Various Antibiotics, Captured from Hamadan City, Iran.

    Science.gov (United States)

    Nazari, Mansour; Mehrabi, Tahereh; Hosseini, Seyed Mostafa; Alikhani, Mohammad Yousef

    2017-04-01

    House flies ( Musca domestica ) have been known as a mechanical vector in spreading infectious diseases such as cholera, shigellosis, salmonellosis and skin infections. To investigate the bacterial contaminations of house flies and determine the resistance of these bacteria against various antibiotics. An analytical descriptive cross- sectional study was conducted. The study was performed from July to September 2015 in Hamadan University of Medical Sciences, Hamadan, Iran. A total number of 300 house flies were collected from four places, 75 flies from each place, including two educational hospitals belonging to Hamadan University of Medical Sciences, a fruit and vegetables center, and a livestock slaughter. The body surface of house flies was washed using the physiological sterile serum and the obtained solution was centrifuged at 2000 rpm for five minutes. The identification of bacteria was carried out using the phenotypic methods. The resistance of bacteria against various antibiotics was determined using the disk diffusion approach. Data were analysed by the employment of SPSS software package version 20.0. A total number of 394 bacterial strains were isolated from 275 house flies. The most prevalent type of bacteria was Bacillus spp which was detected in 31.1% of house flies. Moreover, Staphylococcus s pp. (22.9%), Escherichia coli (11.6%) were other prevalent species, whereas, Enterococcus s pp. was the least prevalent type of bacteria in the collected house flies. In terms of resistance to antibiotics, it was identified that bacteria extracted from house flies which were collected from hospital environments were more resistant to antibiotics compared with the resistance of bacteria extracted from house flies which were collected from non hospital environments. The maximum bacterial isolation was found in houseflies from hospital No.1 environment from around the accumulation of garbage. It is a well-known fact that house flies are a source of bacterial

  18. Dgroup: DG00591 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG00591 Chemical ... DGroup Meropenem ... D08185 ... Meropenem (INN) D02222 ... Meropenem (USP); Meropene...n group ... DG01458 ... Carbapenem ATC code: J01DH02 beta-Lactam antibiotics, carbapenem penicillin binding protein ...

  19. Carbapenemase-producerende enterobacteriën in Nederland : Onopgemerkte versprewiding naar verschillende regio's.

    NARCIS (Netherlands)

    Leenstra, T; Bosch, T; Vlek, A L; Bonten, M J M; van der Lubben, I M; de Greeff, S C

    2017-01-01

    - Carbapenemase producing Enterobacteriaceae (CPE), including Klebsiella pneumoniae and Escherichia coli, are only sporadically seen in the Netherlands and then mainly in patients who have been transferred from foreign hospitals.- CPE are resistant to virtually all beta-lactam antibiotics, including

  20. Reconventionalization following antibiotic decontamination in man and animals

    NARCIS (Netherlands)

    Waaij, D. van der; Vossen, J.M.; Korthals Altes, C.; Hartgrink, C.

    1977-01-01

    Antibiotic decontamination of the digestive tract can suppress or eliminate all microorganisms in this tract that are sensitive to the antibiotics used for decontamination. Experimental work in animals has indicated that colonization resistance (CR) decreases to extremely low values during

  1. Prevalence of bovine mastitis and multi-antibiotic resistant ...

    African Journals Online (AJOL)

    Prevalence of bovine mastitis and multi-antibiotic resistant Staphylococcus and ... Bulletin of Animal Health and Production in Africa ... their antibiotic sensitivities and management practices of sahiwal and dairy cattle kept at a centre of Kenya ...

  2. Prescribing Antibiotics

    DEFF Research Database (Denmark)

    Pedersen, Inge Kryger; Jepsen, Kim Sune

    2018-01-01

    The medical professions will lose an indispensable tool in clinical practice if even simple infections cannot be cured because antibiotics have lost effectiveness. This article presents results from an exploratory enquiry into “good doctoring” in the case of antibiotic prescribing at a time when...... the knowledge base in the healthcare field is shifting. Drawing on in-depth interviews about diagnosing and prescribing, the article demonstrates how the problem of antimicrobial resistance is understood and engaged with by Danish general practitioners. When general practitioners speak of managing “non......-medical issues,” they refer to routines, clinical expertise, experiences with their patients, and decision-making based more on contextual circumstances than molecular conditions—and on the fact that such conditions can be hard to assess. This article’s contribution to knowledge about how new and global health...

  3. Detection of Beta-lactamase gene in the culturable bacteria isolated from agricultural, pasture and mining soils around mines in Hamedan, Iran

    Directory of Open Access Journals (Sweden)

    Nayereh Younessi

    2017-09-01

    Full Text Available Introduction: Growing evidence exists that agriculture affects antibiotic resistance in human pathogens. Beta-lactam antibiotics are the most commonly used antimicrobial agents in many countries. The abundance of beta-lactamase encoding genes can be used as an indicator of antibiotic resistance in the environment. So, to determine the beta-lactamase resistance genes, the abundance of culturable bacteria having bla-TEM genesin the soils under different land uses wasexamined. Materials and methods: 44 Gram-positive and 34 Gram-negative bacteria plated on nutrient agar were isolated from agricultural, pasture and mining soils and selected to study the presence of TEM-class gene using PCR amplification. Antibiotic sensitivity test of bla-TEM+isolateswas done adopting the Kirby-Bauer disk diffusion method and antibiotic discs used were: ampicillin, amoxicillin, vancomicin, streptomycin, tetracycline and gentamicin. Finally, five multi-drug resistant and bla-TEM+ isolates were identified using universal primers. Results: The highest level of beta-lactamase genes was observed in the Gram-positive and Gram-negative isolates from the pasture soils. In the agricultural and mining soils, a high abundance of bla-TEM+ isolateswasfound which also showed resistance to beta-lactam antibiotics. The identified multi-drug resistant and bla-TEM+ isolates were from these genera: Achromobacter, Bacillus, Brevibacillus, Aminobacter and Brevundimonas. Discussion and conclusion: The high number of bla-TEM+ bacteria in all the soils may be attributed to the other important feature of bla genes which is their capability to extrude toxic compounds like heavy metals in contaminated environments. Sensitivity of some bla-TEM+ bacteria to beta-lactam antibiotics was interesting. This result shows that bla-TEM genes confer resistance to beta-lactamase inhibitors in a different degree. Some of the identified isolates were pathogen. These pathogens in soils can transfer to plants

  4. First Report of a Case of Pneumococcal Meningitis Which Did Not Respond to the Ceftriaxone Therapy despite the Isolated Organism Being Sensitive to This Antibiotic In Vitro

    Directory of Open Access Journals (Sweden)

    Maryam Mojtabavi

    2011-01-01

    Full Text Available A 60-year-old man presented with pneumococcal meningitis which did not respond to the ceftriaxone therapy, in spite of in-vitro susceptibility (minimal inhibitory concentration of 0.016 μg/dLit of the isolated organism to this antibacterial agent, although ceftriaxone is still the drug of choice for such pneumococcal meningitis. Review of published articles revealed no report of clinical resistance in organisms which were susceptible to the same antimicrobial agent in vitro. This alarming emergence of isolates with in vivo resistance should be considered and even could lead to a shift in the empirical antibiotic therapy for pneumococcal infections.

  5. Detection of residues antibiotics in food using a microbiological method

    International Nuclear Information System (INIS)

    Ben Ali, Ahmed

    2007-01-01

    Antibiotics are effective therapeutic agents because of their property of selective bacterial toxicity which helps controlling infections. Animals, just like humans, can be treated with antibiotics. This use of antibiotics can lead to the development of resistance. Resistant strains may cause severe infections in humans and animals. In addition, antibiotic residues might represent a problem for human health. Our objective is to develop a microbiological method for the detection of antibiotic residues in poultry(muscle, liver,...). For this purpose, antibiotic sensitive bacteria and selective agar media were used. An inhibition growth zone surrounds each of the food samples containing antibiotic residues after a prescribed incubation time. (Author). 23 refs

  6. Dissemination and genetic support of broad-spectrum beta-lactam ...

    African Journals Online (AJOL)

    Methods: A total of 113 E.coli isolates obtained during the period 2004 through 2012 showed a ... to the PFGE analysis and characterization of the regions surrounding the blaCTX-M-15 ... 240-Gly which increases its catalytic efficiency against.

  7. Is the addition of aminoglycosides to beta-lactams in cancer patients with febrile neutropenia needed?

    OpenAIRE

    Valeria Contreras; Sebastián Sepúlveda; Ana Heredia

    2016-01-01

    En pacientes con cáncer que se presentan con neutropenia febril existe controversia sobre si es mejor utilizar una combinación de antibióticos betalactámicos y aminoglicósidos o si bastaría la monoterapia con betalactámicos de amplio espectro como tratamiento empírico inicial. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en 30 bases de datos, identificamos tres revisiones sistemáticas que en conjunto incluyen 14 estudios aleatorizados pertinentes a esta p...

  8. Is the addition of aminoglycosides to beta-lactams in cancer patients with febrile neutropenia needed?

    Directory of Open Access Journals (Sweden)

    Valeria Contreras

    2016-03-01

    Full Text Available En pacientes con cáncer que se presentan con neutropenia febril existe controversia sobre si es mejor utilizar una combinación de antibióticos betalactámicos y aminoglicósidos o si bastaría la monoterapia con betalactámicos de amplio espectro como tratamiento empírico inicial. Utilizando la base de datos Epistemonikos, la cual es mantenida mediante búsquedas en 30 bases de datos, identificamos tres revisiones sistemáticas que en conjunto incluyen 14 estudios aleatorizados pertinentes a esta pregunta. Realizamos un metanálisis y tablas de resumen de los resultados utilizando el método GRADE. Concluimos que adicionar aminoglicósidos a los betalactámicos en el tratamiento de la neutropenia febril en pacientes con cáncer aumenta la nefrotoxicidad y podría aumentar la mortalidad en comparación con la monoterapia con betalactámicos.

  9. Deletion of Lytic Transglycosylases Increases Beta-Lactam Resistance in Shewanella oneidensis

    Science.gov (United States)

    Yin, Jianhua; Sun, Yiyang; Sun, Yijuan; Yu, Zhiliang; Qiu, Juanping; Gao, Haichun

    2018-01-01

    Production of chromosome-encoded β-lactamases confers resistance to β-lactams in many Gram-negative bacteria. Some inducible β-lactamases, especially the class C β-lactamase AmpC in Enterobacteriaceae, share a common regulatory mechanism, the ampR-ampC paradigm. Induction of ampC is intimately linked to peptidoglycan recycling, and the LysR-type transcriptional regulator AmpR plays a central role in the process. However, our previous studies have demonstrated that the expression of class D β-lactamase gene blaA in Shewanella oneidensis is distinct from the established paradigm since an AmpR homolog is absent and major peptidoglycan recycling enzymes play opposite roles in β-lactamase expression. Given that lytic transglycosylases (LTs), a class of peptidoglycan hydrolases cleaving the β-1,4 glycosidic linkage in glycan strands of peptidoglycan, can disturb peptidoglycan recycling, and thus may affect induction of blaA. In this study, we investigated impacts of such enzymes on susceptibility to β-lactams. Deletion of three LTs (SltY, MltB and MltB2) increased β-lactam resistance, while four other LTs (MltD, MltD2, MltF, and Slt2) seemed dispensable to β-lactam resistance. The double LT mutants ΔmltBΔmltB2 and ΔsltYΔmltB2 had β-lactam resistance stronger than any of the single mutants. Deletion of ampG (encoding permease AmpG) and mrcA (encoding penicillin binding protein 1a, PBP1a) from both double LT mutants further increased the resistance to β-lactams. Notably, all increased β-lactam resistance phenotypes were in accordance with enhanced blaA expression. Although significant, the increase in β-lactamase activity after inactivating LTs is much lower than that produced by PBP1a inactivation. Our data implicate that LTs play important roles in blaA expression in S. oneidensis. PMID:29403465

  10. 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...

  11. Re-sensitizing Multidrug Resistant Bacteria to Antibiotics by Targeting Bacterial Response Regulators: Characterization and Comparison of Interactions between 2-Aminoimidazoles and the Response Regulators BfmR from Acinetobacter baumannii and QseB from Francisella spp.

    Directory of Open Access Journals (Sweden)

    Morgan E. Milton

    2018-02-01

    Full Text Available 2-aminoimidazole (2-AI compounds inhibit the formation of bacterial biofilms, disperse preformed biofilms, and re-sensitize multidrug resistant bacteria to antibiotics. 2-AIs have previously been shown to interact with bacterial response regulators, but the mechanism of interaction is still unknown. Response regulators are one part of two-component systems (TCS. TCSs allow cells to respond to changes in their environment, and are used to trigger quorum sensing, virulence factors, and antibiotic resistance. Drugs that target the TCS signaling process can inhibit pathogenic behavior, making this a potent new therapeutic approach that has not yet been fully exploited. We previously laid the groundwork for the interaction of the Acinetobacter baumannii response regulator BfmR with an early 2-AI derivative. Here, we further investigate the response regulator/2-AI interaction and look at a wider library of 2-AI compounds. By combining molecular modeling with biochemical and cellular studies, we expand on a potential mechanism for interaction between response regulators and 2-AIs. We also establish that Francisella tularensis/novicida, encoding for only three known response regulators, can be a model system to study the interaction between 2-AIs and response regulators. We show that knowledge gained from studying Francisella can be applied to the more complex A. baumannii system, which contains over 50 response regulators. Understanding the impact of 2-AIs on response regulators and their mechanism of interaction will lead to the development of more potent compounds that will serve as adjuvant therapies to broad-range antibiotics.

  12. MASTITE BOVINA: SENSIBILIDADE DE AGENTES ETIOLÓGICOS A ANTIBIÓTICOS E QUIMIOTERÁPICOS BOVINE MASTITIS: SENSITIVITY OF ETIOLOGICAL AGENTS TO ANTIBIOTICS AND CHEMOTHERAPICS

    Directory of Open Access Journals (Sweden)

    Roberval Rodrigues da Costa

    2007-09-01

    Full Text Available

    Foram analisadas 590 amostras de leite procedentes de 701 vacas da bacia leiteira de Goiânia, que apresentaram ao teste de Whiteside/CMT resultado suspeito ou positivo. Foi feito o teste de sensibilidade bacteriana “in vitro” a antibióticos e quimioterápicos dos agentes etiológicos isolados das lactoculturas. Os antibióticos e quimioterápicos testados foram: trimetropim-sulfametazole, tetraciclina, streptomicina cloranfenicol, kanamicina, penicilina G, furadantina, neomicina, eritromicina e novobiocina. As drogas que mostraram a maior ação foram: trimetropim-sulfametazole, cloranfenicol e furadantina; por outro lado, maior resistência foi observada para a penicilina G, streptomicina e eritromicina.

    590 samples of mi1k collected from 701 cows in the milk area around Goiânia were submitted to the Whiteside/CMT test and all suspect or positive. It was also done the bacterial sensibility test “in vitro” to antibiotics and chemotherapics of the aetiological agents isolated from the lactocultures. The antibiotics and chemioterapics tested were as follow: trimetropim-sulfametazole, tetracicline, streptomicine, chloranfenicol, kanamicine, penicilin G, furadantine, neomicine, eritromicine and novobiocine. The drugs which had better action were: trimetropim-sulfametazole, chloranfenicol and furadantine; on the other side, a higher resistance was observed for penicilin G, streptomicine and eritromicine.

  13. Detection of meca gene from methicillin resistant staphylococcus aureus isolates of north sumatera

    Science.gov (United States)

    Septiani Nasution, Gabriella; Suryanto, Dwi; Lia Kusumawati, R.

    2018-03-01

    Methicillin Resistant Staphylococcus aureus (MRSA) is a major pathogen associated with hospital-acquired infections (nosocomial infections). MRSA is a type of S. aureus resistant to the sub-group of beta-lactam antibiotics such as penicillin, cephalosporin, monobactam, and carbapenem. MRSA is resistant because of genetic changes caused by exposure to irrational antibiotic therapy. This study aimed to detect mecA gene in North Sumatra isolates of MRSA and to determine the pattern of antibiotic resistance in S.aureus isolates classified as MRSA by Vitek 2 Compact in the Central Public Hospital Haji Adam Malik, Medan. Samples were 40 isolates of S. aureus classified as MRSA obtained from clinical microbiology specimens. DNA isolation of the isolates was conducted by a method of freeze-thaw cycling. Amplification of mecA gene was done by PCR technique using specific primer for the gene. PCR products were visualized using mini-gel electrophoresis. The results showed that all MRSA isolates showed to have 533 bp band of mecA. Antibiotics test of Vitek 2 Compact showed that despite all isolates were resistant to beta-lactam antibiotics groups; the isolates showed multidrug resistant to other common antibiotics, such as aminoglycosides, macrolides, and fluoroquinolones. However, they were still sensitive to vancomycin (82.5% isolates), linezolid (97.5% isolates), and tigecycline (100% isolates).

  14. Antibiotics as CECs: An Overview of the Hazards Posed by Antibiotics and Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Geoffrey Ivan Scott

    2016-04-01

    Full Text Available ABSTRACTMonitoring programs have traditionally monitored legacy contaminants but are shifting focus to Contaminants of Emerging Concern (CECs. CECs present many challenges for monitoring and assessment, because measurement methods don't always exist nor have toxicological studies been fully conducted to place results in proper context. Also some CECs affect metabolic pathways to produce adverse outcomes that are not assessed through traditional toxicological evaluations. Antibiotics are CECs that pose significant environmental risks including development of both toxic effects at high doses and antibiotic resistance at doses well below the Minimum Inhibitory Concentration (MIC which kill bacteria and have been found in nearly half of all sites monitored in the US. Antimicrobial resistance has generally been attributed to the use of antibiotics in medicine for humans and livestock as well as aquaculture operations. The objective of this study was to assess the extent and magnitude of antibiotics in the environment and estimate their potential hazards in the environment. Antibiotics concentrations were measured in a number of monitoring studies which included Waste Water Treatment Plants (WWTP effluent, surface waters, sediments and biota. A number of studies reported levels of Antibiotic Resistant Microbes (ARM in surface waters and some studies found specific ARM genes (e.g. the blaM-1 gene in E. coli which may pose additional environmental risk. High levels of this gene were found to survive WWTP disinfection and accumulated in sediment at levels 100-1000 times higher than in the sewerage effluent, posing potential risks for gene transfer to other bacteria.in aquatic and marine ecosystems. Antibiotic risk assessment approaches were developed based on the use of MICs and MIC Ratios [High (Antibiotic Resistant/Low (Antibiotic Sensitive MIC] for each antibiotic indicating the range of bacterial adaptability to each antibiotic to help define the No

  15. Incidence and antibiotic susceptibility pattern of Staphylococcus ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-03

    Jun 3, 2008 ... antibiotic sensitivity test results of suspected cases of urinary tract infection (UTI) of the University of ... (4.4%), Pseudomonas aeruginosa (2.0%) and Candida albican (1.0%). ... and oxfloxacin could be the drug of choice in the treatment of S. aureus. ... appropriate empirical antibiotics that could be of use.

  16. Long-term field application of sewage sludge increases the abundance of antibiotic resistance genes in soil.

    Science.gov (United States)

    Chen, Qinglin; An, Xinli; Li, Hu; Su, Jianqiang; Ma, Yibing; Zhu, Yong-Guan

    2016-01-01

    Sewage sludge and manure are common soil amendments in crop production; however, their impact on the abundance and diversity of the antibiotic resistome in soil remains elusive. In this study, by using high-throughput sequencing and high-throughput quantitative PCR, the patterns of bacterial community and antibiotic resistance genes (ARGs) in a long-term field experiment were investigated to gain insights into these impacts. A total of 130 unique ARGs and 5 mobile genetic elements (MGEs) were detected and the long-term application of sewage sludge and chicken manure significantly increased the abundance and diversity of ARGs in the soil. Genes conferring resistance to beta-lactams, tetracyclines, and multiple drugs were dominant in the samples. Sewage sludge or chicken manure applications caused significant enrichment of 108 unique ARGs and MGEs with a maximum enrichment of up to 3845 folds for mexF. The enrichment of MGEs suggested that the application of sewage sludge or manure may accelerate the dissemination of ARGs in soil through horizontal gene transfer (HGT). Based on the co-occurrence pattern of ARGs subtypes revealed by network analysis, aacC, oprD and mphA-02, were proposed to be potential indicators for quantitative estimation of the co-occurring ARGs subtypes abundance by power functions. The application of sewage sludge and manure resulted in significant increase of bacterial diversity in soil, Proteobacteria, Acidobacteria, Actinobacteria and Chloroflexi were the dominant phyla (>10% in each sample). Five bacterial phyla (Chloroflexi, Planctomycetes, Firmicutes, Gemmatimonadetes and Bacteroidetes) were found to be significantly correlated with the ARGs in soil. Mantel test and variation partitioning analysis (VPA) suggested that bacterial community shifts, rather than MGEs, is the major driver shaping the antibiotic resistome. Additionally, the co-occurrence pattern between ARGs and microbial taxa revealed by network analysis indicated that four

  17. Sublethal Concentrations of Antibiotics Cause Shift to Anaerobic Metabolism in Listeria monocytogenes and Induce Phenotypes Linked to Antibiotic Tolerance

    DEFF Research Database (Denmark)

    Knudsen, Gitte Maegaard; Fromberg, Arvid; Ng, Yin

    2016-01-01

    The human pathogenic bacterium Listeria monocytogenes is exposed to antibiotics both during clinical treatment and in its saprophytic lifestyle. As one of the keys to successful treatment is continued antibiotic sensitivity, the purpose of this study was to determine if exposure to sublethal...... antibiotic concentrations would affect the bacterial physiology and induce antibiotic tolerance. Transcriptomic analyses demonstrated that each of the four antibiotics tested caused an antibiotic-specific gene expression pattern related to mode-of-action of the particular antibiotic. All four antibiotics...... in Imo1179 (eutE) encoding an aldehyde oxidoreductase where rerouting caused increased ethanol production was tolerant to three of four antibiotics tested. This shift in metabolism could be a survival strategy in response to antibiotics to avoid generation of ROS production from respiration by oxidation...

  18. Antibiotic Resistance

    DEFF Research Database (Denmark)

    Hansen, Malene Plejdrup; Hoffmann, Tammy C; McCullough, Amanda R

    2015-01-01

    hygiene, and possibly vaccination and exercise, may be effective. Also, a large range of complementary and alternative medicines (e.g. zinc, vitamin C and probiotics) are proposed for preventing and treating ARIs, but evidence for efficacy is scarce. General practitioners' (GPs) attitudes towards...... wrong. Shared decision making might be a solution, as it enables clinician and patient to participate jointly in making a health decision, having discussed the options together with the evidence for their harms as well as benefits. Furthermore, GPs' diagnostic uncertainty - often leading...... will greatly improve the use of antibiotics for ARIs. However, used in concert, combinations are likely to enable clinicians and health care systems to implement the strategies that will reduce antimicrobial resistance in the future....

  19. Antibiotic Resistance Pattern and Molecular Epidemiology of ...

    African Journals Online (AJOL)

    2099 ... Veterinary Medicine, Seoul National University 151-742, Korea, 3Institute of Basic Medical Sciences, Khyber Medical University, .... Culture sensitivity data for 16 antibiotics were recorded .... occupancy and cross-transmission of MRSA.

  20. tration on Phenotypic Antibiotic Susceptibility and Resistance

    African Journals Online (AJOL)

    resistance in bacteria of food animal origin (Van den Bogaard and Stobberingh, ... however, the effect of antimicrobial drug use in companion animals like dogs or ...... Antibiotic sensitivity of bacterial isolates from cases of canine dermatitis.

  1. Antibiotics Susceptibility Pattern of Pseudomonas aeruginosa ...

    African Journals Online (AJOL)

    ABSTRACT: This work investigated the prevalence and antibiotics sensitivity of Pseudomonas aeruginosa isolated from ... skin triggers coagulation and an acute inflammatory response ... agents with anti-pseudomonal activity, life-threatening.

  2. Microbial resistance to antibiotics | Chinedum | African Journal of ...

    African Journals Online (AJOL)

    Organisms that are normally sensitive to the action of an antibiotic may sometimes develop resistance or insensitivity to it. This, they may do through destroying the antibiotic or by retaining their growth even in the presence of the drug. Microbial resistance to antibiotics is now widespread and poses a serious clinical threat.

  3. A non-polyene antifungal antibiotic from Streptomyces albidoflavus ...

    Indian Academy of Sciences (India)

    Unknown

    One promising strain, Streptomyces albidoflavus PU 23 with strong anti- fungal activity against pathogenic fungi was selected for further studies. Antibiotic was extracted and purified from the isolate. Aspergillus spp. was most sensitive to the antibiotic followed by other molds and yeasts. The antibiotic was stable at different ...

  4. Gene expression at each stage of the life cycle of spore-forming bacteria: different sensitivity of transcription to antibiotics which act on DNA gyrase.

    Science.gov (United States)

    Matsuda, M; Kameyama, T

    1985-01-01

    Effects of antibiotics acting on DNA gyrase, novobiocin and nalidixic acid on RNA synthesis during germination, vegetative growth and sporulation of Bacillus subtilis were examined. These drugs were relatively ineffective in inhibiting RNA synthesis of phase Gm 1 (5-15 min) during germination but effective in those of Gm 2 (15-40 min) and Gm 3 (40-60 min) during germination (Matsuda and Kameyama 1980). No distinguishable inhibitory effects of RNA synthesis in B. subtilis NOVr1TT mutant could be detected by novobiocin. RNA synthesis of Gm 2 and Gm 3 of this mutant was inhibited by nalidixic acid. When novobiocin was added to exponential vegetative cell or sporulating cell culture at T0 and T1 stage, the rate of RNA synthesis was inhibited by 80% for 5 min following addition of the drug. However, RNA synthesis after T2 of sporulation became resistant toward novobiocin, as was the case at an early stage of germination. RNA profiles from transcripts synthesized on administration of NOV suggested that the suppression of the synthesis of 23S and 16S rRNA is relatively greater than 4 to 5S RNA at the middle stage of germination and at vegetative growth stage in the presence of NOV. Our present data suggest that DNA gyrase is involved in the regulation of gene transcription during middle and late phases of germination, vegetative growth and T0 and T1 of sporulation. The transcription during early phase of germination and sporulation after T2 may proceed independently of this enzyme.

  5. Demographics of antibiotic persistence

    DEFF Research Database (Denmark)

    Kollerova, Silvia; Jouvet, Lionel; Steiner, Ulrich

    Persister cells, cells that can survive antibiotic exposure but lack heritable antibiotic resistance, are assumed to play a crucial role for the evolution of antibiotic resistance. Persistence is a stage associated with reduced metabolic activity. Most previous studies have been done on batch...... even play a more prominent role for the evolution of resistance and failures of medical treatment by antibiotics as currently assumed....

  6. Evaluation of Offline Tandem and Online Solid-Phase Extraction with Liquid Chromatography/Electrospray Ionization-Mass Spectrometry for Analysis of Antibiotics in Ambient Water and Comparison to an Independent Method

    Science.gov (United States)

    Meyer, M.T.; Lee, E.A.; Ferrell, G.M.; Bumgarner, J.E.; Varns, Jerry

    2007-01-01

    This report describes the performance of an offline tandem solid-phase extraction (SPE) method and an online SPE method that use liquid chromatography/mass spectrometry for the analysis of 23 and 35 antibiotics, respectively, as used in several water-quality surveys conducted since 1999. In the offline tandem SPE method, normalized concentrations for the quinolone, macrolide, and sulfonamide antibiotics in spiked environmental samples averaged from 81 to 139 percent of the expected spiked concentrations. A modified standard-addition technique was developed to improve the quantitation of the tetracycline antibiotics, which had 'apparent' concentrations that ranged from 185 to 1,200 percent of their expected spiked concentrations in matrix-spiked samples. In the online SPE method, normalized concentrations for the quinolone, macrolide, sulfonamide, and tetracycline antibiotics in matrix-spiked samples averaged from 51 to 142 percent of their expected spiked concentrations, and the beta-lactam antibiotics in matrix-spiked samples averaged from 22 to 76 percent of their expected spiked concentration. Comparison of 44 samples analyzed by both the offline tandem SPE and online SPE methods showed 50 to 100 percent agreement in sample detection for overlapping analytes and 68 to 100 percent agreement in a presence-absence comparison for all analytes. The offline tandem and online SPE methods were compared to an independent method that contains two overlapping antibiotic compounds, sulfamethoxazole and trimethoprim, for 96 and 44 environmental samples, respectively. The offline tandem SPE showed 86 and 92 percent agreement in sample detection and 96 and 98 percent agreement in a presence-absence comparison for sulfamethoxazole and trimethoprim, respectively. The online SPE method showed 57 and 56 percent agreement in sample detection and 72 and 91 percent agreement in presence-absence comparison for sulfamethoxazole and trimethoprim, respectively. A linear regression with

  7. First identification of class A carbapenemase-producing Klebsiella pneumoniae in the Republic of Ireland.

    LENUS (Irish Health Repository)

    Roche, C

    2009-04-02

    The Klebsiella pneumoniae carbapenemase (KPC) was detected in a carbapenem-resistant respiratory isolate of Klebsiella pneumoniae in an Irish hospital. This is the first report of a KPC-producing isolate in the Republic of Ireland. The isolate was resistant to all beta-lactams. Furthermore, it had reduced susceptibility to three other classes of non-beta-lactam antibiotics. The isolate was not associated with travel abroad. Detection of KPC-producing bacteria has important infection control and public health implications.

  8. Ad Hoc Constitution of Topical Antibiotics Solution for Ear Dressing ...

    African Journals Online (AJOL)

    Background/ Purpose: In the management of chronic suppurative otitis media and otitis externa there are few cases where although an organism is cultured and isolated from the ear, there are either no antibiotic sensitive to the microbiological flora or the sensitive antibiotic is not available in the form of an ear drop, limiting ...

  9. Antibiotic resistant Staphylococcus aureus in Abia State of Nigeria ...

    African Journals Online (AJOL)

    The S. aureus. isolates varied in their antibiotic susceptibility pattern when tested for their sensitivity to 16 antibiotics. Eighty percent of the isolates were resistant to more than one antimicrobial agent. All the isolates showed resistance to nalidixic acid and 100% sensitivity to rifampicin. Key words: Staphylococcus aureus, ...

  10. Bacterial Cheating Limits the Evolution of Antibiotic Resistance

    Science.gov (United States)

    Yurtsev, Eugene; Xiao Chao, Hui; Datta, Manoshi; Artemova, Tatiana; Gore, Jeff

    2012-02-01

    The emergence of antibiotic resistance in bacteria is a significant health concern. Bacteria can gain resistance to the antibiotic ampicillin by acquiring a plasmid carrying the gene beta-lactamase, which inactivates the antibiotic. This inactivation may represent a cooperative behavior, as the entire bacterial population benefits from removal of the antibiotic. The presence of a cooperative mechanism of resistance suggests that a cheater strain - which does not contribute to breaking down the antibiotic - may be able to take advantage of resistant cells. We find experimentally that a ``sensitive'' bacterial strain lacking the plasmid conferring resistance can invade a population of resistant bacteria, even in antibiotic concentrations that should kill the sensitive strain. We use a simple model in conjunction with difference equations to explain the observed population dynamics as a function of cell density and antibiotic concentration. Our experimental difference equations resemble the logistic map, raising the possibility of oscillations or even chaotic dynamics.

  11. Evaluation of a Mixing versus a Cycling Strategy of Antibiotic Use in Critically-Ill Medical Patients: Impact on Acquisition of Resistant Microorganisms and Clinical Outcomes.

    Directory of Open Access Journals (Sweden)

    Nazaret Cobos-Trigueros

    Full Text Available To compare the effect of two strategies of antibiotic use (mixing vs. cycling on the acquisition of resistant microorganisms, infections and other clinical outcomes.Prospective cohort study in an 8-bed intensive care unit during 35- months in which a mixing-cycling policy of antipseudomonal beta-lactams (meropenem, ceftazidime/piperacillin-tazobactam and fluoroquinolones was operative. Nasopharyngeal and rectal swabs and respiratory secretions were obtained within 48h of admission and thrice weekly thereafter. Target microorganisms included methicillin-resistant S. aureus, vancomycin-resistant enterococci, third-generation cephalosporin-resistant Enterobacteriaceae and non-fermenters.A total of 409 (42% patients were included in mixing and 560 (58% in cycling. Exposure to ceftazidime/piperacillin-tazobactam and fluoroquinolones was significantly higher in mixing while exposure to meropenem was higher in cycling, although overall use of antipseudomonals was not significantly different (37.5/100 patient-days vs. 38.1/100 patient-days. There was a barely higher acquisition rate of microorganisms during mixing, but this difference lost its significance when the cases due to an exogenous Burkholderia cepacia outbreak were excluded (19.3% vs. 15.4%, OR 0.8, CI 0.5-1.1. Acquisition of Pseudomonas aeruginosa resistant to the intervention antibiotics or with multiple-drug resistance was similar. There were no significant differences between mixing and cycling in the proportion of patients acquiring any infection (16.6% vs. 14.5%, OR 0.9, CI 0.6-1.2, any infection due to target microorganisms (5.9% vs. 5.2%, OR 0.9, CI 0.5-1.5, length of stay (median 5 d for both groups or mortality (13.9 vs. 14.3%, OR 1.03, CI 0.7-1.3.A cycling strategy of antibiotic use with a 6-week cycle duration is similar to mixing in terms of acquisition of resistant microorganisms, infections, length of stay and mortality.

  12. The antibiotic resistome.

    Science.gov (United States)

    Wright, Gerard D

    2010-08-01

    Antibiotics are essential for the treatment of bacterial infections and are among our most important drugs. Resistance has emerged to all classes of antibiotics in clinical use. Antibiotic resistance has, proven inevitable and very often it emerges rapidly after the introduction of a drug into the clinic. There is, therefore, a great interest in understanding the origins, scope and evolution of antibiotic resistance. The review discusses the concept of the antibiotic resistome, which is the collection of all genes that directly or indirectly contribute to antibiotic resistance. The review seeks to assemble current knowledge of the resistome concept as a means of understanding the totality of resistance and not just resistance in pathogenic bacteria. The concept of the antibiotic resistome provides a framework for the study and understanding of how resistance emerges and evolves. Furthermore, the study of the resistome reveals strategies that can be applied in new antibiotic discoveries.

  13. How Nature Morphs Peptide Scaffolds into Antibiotics

    Science.gov (United States)

    Nolan, Elizabeth M.; Walsh, Christopher T.

    2010-01-01

    The conventional notion that peptides are poor candidates for orally available drugs because of protease-sensitive peptide bonds, intrinsic hydrophilicity, and ionic charges contrasts with the diversity of antibiotic natural products with peptide-based frameworks that are synthesized and utilized by Nature. Several of these antibiotics, including penicillin and vancomycin, are employed to treat bacterial infections in humans and have been best-selling therapeutics for decades. Others might provide new platforms for the design of novel therapeutics to combat emerging antibiotic-resistant bacterial pathogens. PMID:19058272

  14. Know When Antibiotics Work

    Centers for Disease Control (CDC) Podcasts

    2015-04-15

    This podcast provides a brief background about antibiotics and quick tips to help prevent antibiotic resistance.  Created: 4/15/2015 by Division of Bacterial Diseases (DBD), National Center for Immunization and Respiratory Disease (NCIRD), Get Smart: Know When Antibiotics Work Program.   Date Released: 4/16/2015.

  15. Antibiotics: Miracle Drugs

    Centers for Disease Control (CDC) Podcasts

    The overuse of antibiotics has led to the development of resistance among bacteria, making antibiotics ineffective in treating certain conditions. This podcast discusses the importance of talking to your healthcare professional about whether or not antibiotics will be beneficial if you've been diagnosed with an infectious disease.

  16. Dgroup: DG00533 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ... DG01480 ... Penam ... DG01780 ... Extended spectrum penicillin ATC code: J01CA19 Antibacterial, Cell wall biosynt...hesis inhibitor beta-Lactam, penicillin, penicillinase-sensitive, Semisynthetic penicillin: extended spectrum penicillin penicillin binding protein ...

  17. Systemic antibiotics in periodontics.

    Science.gov (United States)

    Slots, Jørgen

    2004-11-01

    This position paper addresses the role of systemic antibiotics in the treatment of periodontal disease. Topical antibiotic therapy is not discussed here. The paper was prepared by the Research, Science and Therapy Committee of the American Academy of Periodontology. The document consists of three sections: 1) concept of antibiotic periodontal therapy; 2) efficacy of antibiotic periodontal therapy; and 3) practical aspects of antibiotic periodontal therapy. The conclusions drawn in this paper represent the position of the American Academy of Periodontology and are intended for the information of the dental profession.

  18. An International Model for Antibiotics Regulation.

    Science.gov (United States)

    Aguirre, Emilie

    We face a global antibiotics resistance crisis. Antibiotic drugs are rapidly losing their effectiveness, potentially propelling us toward a post-antibiotic world. The largest use of antibiotics in the world is in food-producing animals. Food producers administer these drugs in routine, low doses—the types of doses that are incidentally the most conducive to breeding antibiotic resistance. In general, individual countries have been too slow to act in regulating misuse and overuse of antibiotics in foodproducing animals. This problem will only worsen with the significant projected growth in meat consumption and production expected in emerging economies in the near future. Although individual countries regulating antibiotics can have important effects, one country alone cannot insulate itself entirely from the effects of antibiotic resistance, nor can one country solve the crisis for itself or for the world. The global nature of the food system and the urgency of the problem require immediate global solutions. Adapting a democratic experimentalist approach at the international level can help achieve this goal. Using an international democratic experimentalist framework in conjunction with the World Organization for Animal Health (OIE) would provide for increased systematized data collection and lead to heightened, scientifically informed OIE standards, enforceable by the World Trade Organization (WTO), which could have a significant impact on the reduction of subtherapeutic use of antibiotics internationally. International democratic experimentalism addresses the global intricacy, time sensitivity, context- and culture-specificity, and knowledgeintensiveness of this problem. By encouraging more countries to experiment to solve this problem, the democratic experimentalist model would help develop a larger database of solutions to enable more meaningful cross-country comparisons across a wider range of contexts. This approach maintains democratic governance and

  19. Antibiotic-Induced Changes to the Host Metabolic Environment Inhibit Drug Efficacy and Alter Immune Function

    DEFF Research Database (Denmark)

    Yang, Jason H.; Bhargava, Prerna; McCloskey, Douglas

    2017-01-01

    Bactericidal antibiotics alter microbial metabolism as part of their lethality and can damage mitochondria in mammalian cells. In addition, antibiotic susceptibility is sensitive to extracellular metabolites, but it remains unknown whether metabolites present at an infection site can affect eithe...

  20. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    ISSN: 0189 1731. Available online at ... Marketing of fish in Nigeria is mostly carried out by local fish .... 8 (34.8). E. coli. 8 (17.8). 4 (18.2). 4 (17.4). Pseudomonas sp. 4 (8.9). 3 (13.6). 1 (4.4) .... related mould generally grow faster and are more ...

  1. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Benin, Benin City. 2 Department of Science Laboratory Technology, Faculty of Life Sciences, University .... 8 (34.8). E. coli. 8 (17.8). 4 (18.2). 4 (17.4). Pseudomonas sp. 4 (8.9). 3 (13.6). 1 (4.4) .... Sengor, G.F, Kalafatogu, H. and Gun, H. (2004).

  2. Utility of galactomannan antigen detection in bronchoalveolar lavage fluid in immunocompromised patients.

    Science.gov (United States)

    Brownback, Kyle R; Pitts, Lucas R; Simpson, Steven Q

    2013-09-01

    Diagnosis of invasive pulmonary aspergillosis (IPA) is a challenging process in immunocompromised patients. Galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) fluid is a method to detect IPA with improved sensitivity over conventional studies. We sought to determine the diagnostic yield of BAL GM assay in a diverse population of immunocompromised patients. A retrospective review of 150 fiberoptic bronchoscopy (FOB) with BAL for newly diagnosed pulmonary infiltrate in immunocompromised patients was performed. Patient information, procedural details and laboratory studies were collected. BAL and serum samples were evaluated for GM using enzyme-linked immunoassay. Of 150 separate FOB with BAL, BAL GM was obtained in 143 samples. There were 31 positive BAL GM assays. In those 31 positive tests, 13 were confirmed as IPA, giving a positive predictive value of 41.9%. There was one false negative BAL GM. Of the 18 false positive BAL GM, 4 were receiving piperacillin-tazobactam and 11 were receiving an alternative beta-lactam antibiotic. BAL GM assay shows excellent sensitivity for diagnosing IPA. There was a significant number of false positive BAL GM assays and several of those patients were receiving beta-lactam antibiotics at the time of bronchoscopy. © 2013 Blackwell Verlag GmbH.

  3. Molecular Regulation of Antibiotic Biosynthesis in Streptomyces

    Science.gov (United States)

    Liu, Gang; Chandra, Govind; Niu, Guoqing

    2013-01-01

    SUMMARY Streptomycetes are the most abundant source of antibiotics. Typically, each species produces several antibiotics, with the profile being species specific. Streptomyces coelicolor, the model species, produces at least five different antibiotics. We review the regulation of antibiotic biosynthesis in S. coelicolor and other, nonmodel streptomycetes in the light of recent studies. The biosynthesis of each antibiotic is specified by a large gene cluster, usually including regulatory genes (cluster-situated regulators [CSRs]). These are the main point of connection with a plethora of generally conserved regulatory systems that monitor the organism's physiology, developmental state, population density, and environment to determine the onset and level of production of each antibiotic. Some CSRs may also be sensitive to the levels of different kinds of ligands, including products of the pathway itself, products of other antibiotic pathways in the same organism, and specialized regulatory small molecules such as gamma-butyrolactones. These interactions can result in self-reinforcing feed-forward circuitry and complex cross talk between pathways. The physiological signals and regulatory mechanisms may be of practical importance for the activation of the many cryptic secondary metabolic gene cluster pathways revealed by recent sequencing of numerous Streptomyces genomes. PMID:23471619

  4. Ribosomal Antibiotics: Contemporary Challenges

    Directory of Open Access Journals (Sweden)

    Tamar Auerbach-Nevo

    2016-06-01

    Full Text Available Most ribosomal antibiotics obstruct distinct ribosomal functions. In selected cases, in addition to paralyzing vital ribosomal tasks, some ribosomal antibiotics are involved in cellular regulation. Owing to the global rapid increase in the appearance of multi-drug resistance in pathogenic bacterial strains, and to the extremely slow progress in developing new antibiotics worldwide, it seems that, in addition to the traditional attempts at improving current antibiotics and the intensive screening for additional natural compounds, this field should undergo substantial conceptual revision. Here, we highlight several contemporary issues, including challenging the common preference of broad-range antibiotics; the marginal attention to alterations in the microbiome population resulting from antibiotics usage, and the insufficient awareness of ecological and environmental aspects of antibiotics usage. We also highlight recent advances in the identification of species-specific structural motifs that may be exploited for the design and the creation of novel, environmental friendly, degradable, antibiotic types, with a better distinction between pathogens and useful bacterial species in the microbiome. Thus, these studies are leading towards the design of “pathogen-specific antibiotics,” in contrast to the current preference of broad range antibiotics, partially because it requires significant efforts in speeding up the discovery of the unique species motifs as well as the clinical pathogen identification.

  5. Bacterial biofilms and antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Liliana Caldas-Arias

    2015-04-01

    Full Text Available Biofilms give to bacteria micro-environmental benefits; confers protection against antimicrobials. Bacteria have antibiotic resistance by conventional and unusual mechanisms leading to delayed wound healing, to increase recurrent chronic infections and nosocomial contamination of medical devices. Objective: This narrative review aims to introduce the characteristics of Bacteria-biofilms, antimicrobial resistance mechanisms and potential alternatives for prevention and control of its formation. Methods: Search strategy was performed on records: PubMed / Medline, Lilacs, Redalyc; with suppliers such as EBSCO and thesaurus MeSH and DeCS. Conclusions: Knowledge and research performance of biofilm bacteria are relevant in the search of technology for detection and measuring sensitivity to antibiotics. The identification of Bacterial-biofilms needs no-traditional microbiological diagnosis.

  6. Antibiotics and Breastfeeding.

    Science.gov (United States)

    de Sá Del Fiol, Fernando; Barberato-Filho, Silvio; de Cássia Bergamaschi, Cristiane; Lopes, Luciane Cruz; Gauthier, Timothy P

    2016-01-01

    During the breastfeeding period, bacterial infections can occur in the nursing mother, requiring the use of antibiotics. A lack of accurate information may lead health care professionals and mothers to suspend breastfeeding, which may be unnecessary. This article provides information on the main antibiotics that are appropriate for clinical use and the interference of these antibiotics with the infant to support medical decisions regarding the discontinuation of breastfeeding. We aim to provide information on the pharmacokinetic factors that interfere with the passage of antibiotics into breast milk and the toxicological implications of absorption by the infant. Publications related to the 20 most frequently employed antibiotics and their transfer into breast milk were evaluated. The results demonstrate that most antibiotics in clinical use are considered suitable during breastfeeding; however, the pharmacokinetic profile of each drug must be observed to ensure the resolution of the maternal infection and the safety of the infant. © 2016 S. Karger AG, Basel.

  7. High Antibiotic Consumption

    DEFF Research Database (Denmark)

    Malo, Sara; José Rabanaque, María; Feja, Cristina

    2014-01-01

    Heavy antibiotic users are those individuals with the highest exposure to antibiotics. They play an important role as contributors to the increasing risk of antimicrobial resistance. We applied different methods to identify and characterize the group of heavy antibiotic users in Spain as well...... as their exposure to antibiotics. Data on outpatient prescribing of antimicrobials (ATC J01) in 2010 were obtained from a prescription database covering Aragón (northeastern Spain). The antimicrobial consumption at the individual level was analysed both according to the volume of DDD and the number of packages...... purchased per year. Heavy antibiotic users were identified according to Lorenz curves and characterized by age, gender, and their antimicrobial prescription profile. Lorenz curves demonstrated substantial differences in the individual use of antimicrobials. Heavy antibiotic users (5% of individuals...

  8. Structure of polysaccharide antibiotics

    International Nuclear Information System (INIS)

    Matutano, L.

    1966-01-01

    Study of the structure of antibiotics having two or several sugars in their molecule. One may distinguish: the polysaccharide antibiotics themselves, made up of two or several sugars either with or without nitrogen, such as streptomycin, neomycins, paromomycine, kanamycin, chalcomycin; the hetero-polysaccharide antibiotics made up of one saccharide part linked to an aglycone of various type through a glucoside: macrolide, pigment, pyrimidine purine. Amongst these latter are: erythromycin, magnamycin, spiramycin, oleandomycin, cinerubin and amicetin. The sugars can either play a direct role in biochemical reactions or act as a dissolving agent, as far as the anti-microbe power of these antibiotics is concerned. (author) [fr

  9. Antibiotics: Miracle Drugs

    Centers for Disease Control (CDC) Podcasts

    2015-04-16

    The overuse of antibiotics has led to the development of resistance among bacteria, making antibiotics ineffective in treating certain conditions. This podcast discusses the importance of talking to your healthcare professional about whether or not antibiotics will be beneficial if you’ve been diagnosed with an infectious disease.  Created: 4/16/2015 by Division of Bacterial Diseases (DBD), National Center for Immunization and Respiratory Disease (NCIRD), Get Smart: Know When Antibiotics Work Program.   Date Released: 4/16/2015.

  10. A non-polyene antifungal antibiotic from Streptomyces albidoflavus ...

    Indian Academy of Sciences (India)

    Out of these, 22% of the isolates exhibited activity against fungi. One promising strain, Streptomyces albidoflavus PU 23 with strong antifungal activity against pathogenic fungi was selected for further studies. Antibiotic was extracted and purified from the isolate. Aspergillus spp. was most sensitive to the antibiotic followed by ...

  11. In Vitro Antibiotic Susceptibility Studies Of Bacteria Associated With ...

    African Journals Online (AJOL)

    In vitro tests of the susceptibility of isolates of bacterial keratitis pathogens to antibiotics were carried out in this study. Staphylococcus aureus was the most frequently isolated organisms followed by Pseudomonas aeruginosa and Streptococcus pneumoniae. Antibiotic sensitivity testing showed a high susceptibility to ...

  12. Antibiotic Resistance and Virulence Properties in Escherichia coli ...

    African Journals Online (AJOL)

    This study determined E. coli resistance to commonly used antibiotics together with their virulence properties in Ile-Ife, Nigeria. A total of 137 E. coli isolates from cases of urinary tract infection were tested for their sensitivity to commonly used antibiotics and possession of virulence factors using standard methods.

  13. Handling Time-dependent Variables : Antibiotics and Antibiotic Resistance

    NARCIS (Netherlands)

    Munoz-Price, L. Silvia; Frencken, Jos F.; Tarima, Sergey; Bonten, Marc

    2016-01-01

    Elucidating quantitative associations between antibiotic exposure and antibiotic resistance development is important. In the absence of randomized trials, observational studies are the next best alternative to derive such estimates. Yet, as antibiotics are prescribed for varying time periods,

  14. Role of MexAB-OprM and MexXY-OprM efflux pumps and class 1 integrons in resistance to antibiotics in burn and Intensive Care Unit isolates of Pseudomonas aeruginosa.

    Science.gov (United States)

    Goli, Hamid Reza; Nahaei, Mohammad Reza; Ahangarzadeh Rezaee, Mohammad; Hasani, Alka; Samadi Kafil, Hossein; Aghazadeh, Mohammad; Nikbakht, Mojtaba; Khalili, Younes

    2017-10-06

    The overexpression of efflux pumps and existence of class 1 integrons are the most important mechanisms that contribute to antimicrobial resistance in Pseudomonas aeruginosa especially in burn and Intensive Care Units (ICUs). The present study evaluated the role of MexAB-OprM and MexXY-OprM efflux pumps and class 1 integrons in resistance to antibiotics in burn and ICU isolates of P. aeruginosa. Fifteen burn and forty-two ICU isolates were obtained from four hospitals in Northwest Iran. The isolates were identified and evaluated by the disk diffusion and agar dilution methods for determining antibiotic resistances. The presence of class 1 integrons and associated resistance gene cassettes were detected by PCR and sequencing of the products. The expression levels of efflux pumps were evaluated by phenotypic and genotypic (Quantitative Real-time PCR) methods. The isolates were genotyped by Random Amplified Polymorphic DNA Typing (RAPD-PCR). All burn isolates were integron positive and Multi-drug resistant (MDR), while 78.5% and 69% of ICU isolates were found as MDR and integron positive, respectively. The aadB gene was the most prevalent gene cassette (63.6%) followed by aacA4 (47.7%). Thirty-nine (68.4%) and 43 (75.4%) isolates exhibited an overexpression of MexAB-OprM and MexXY-OprM. Among burn isolates, 80% and 86.6% of them were mexB and mexY overexpressed, while 64.2% and 71.4% of ICU isolates exhibited mexB and mexY overexpression, correspondingly. The isolates were genotyped as 24 different RAPD profiles and were grouped into 15 clusters. The data suggested that class 1 integron had a more significant role than efflux pumps in resistance to beta-lactams and aminoglycosides in burn and ICUs except for gentamicin in burn isolates. Based on our data, it is possible that efflux pumps were not the main cause of high-level resistance to antibiotics. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. [Antibiotics: present and future].

    Science.gov (United States)

    Bérdy, János

    2013-04-14

    The author discuss the up to date interpretation of the concept of antibiotics and antibiotic research, as well as the present role of various natural, semisynthetic and synthetic antibiotic compounds in various areas of the human therapy. The origin and the total number of all antibiotics and applied antibiotics in the practice, as well as the bioactive microbial metabolites (antibiotics) in other therapeutical, non-antibiotic fields (including agriculture) are also reviewed. The author discusses main problems, such as increasing (poly)resistance, virulence of pathogens and the non-scientific factors (such as a decline of research efforts and their sociological, economic, financial and regulatory reasons). A short summary of the history of Hungarian antibiotic research is also provided. The author briefly discusses the prospects in the future and the general advantages of the natural products over synthetic compounds. It is concluded that new approaches for the investigation of the unlimited possibilities of the living world are necessary. The discovery of new types or simply neglected (micro)organisms and their biosynthetic capabilities, the introduction of new biotechnological and genetic methods (genomics, metagenom, genome mining) are absolutely required in the future.

  16. The future of antibiotics

    Science.gov (United States)

    2014-01-01

    Antibiotic resistance continues to spread even as society is experiencing a market failure of new antibiotic research and development (R&D). Scientific, economic, and regulatory barriers all contribute to the antibiotic market failure. Scientific solutions to rekindle R&D include finding new screening strategies to identify novel antibiotic scaffolds and transforming the way we think about treating infections, such that the goal is to disarm the pathogen without killing it or modulate the host response to the organism without targeting the organism for destruction. Future economic strategies are likely to focus on ‘push’ incentives offered by public-private partnerships as well as increasing pricing by focusing development on areas of high unmet need. Such strategies can also help protect new antibiotics from overuse after marketing. Regulatory reform is needed to re-establish feasible and meaningful traditional antibiotic pathways, to create novel limited-use pathways that focus on highly resistant infections, and to harmonize regulatory standards across nations. We need new antibiotics with which to treat our patients. But we also need to protect those new antibiotics from misuse when they become available. If we want to break the cycle of resistance and change the current landscape, disruptive approaches that challenge long-standing dogma will be needed. PMID:25043962

  17. History of Antibiotics Research.

    Science.gov (United States)

    Mohr, Kathrin I

    2016-01-01

    For thousands of years people were delivered helplessly to various kinds of infections, which often reached epidemic proportions and have cost the lives of millions of people. This is precisely the age since mankind has been thinking of infectious diseases and the question of their causes. However, due to a lack of knowledge, the search for strategies to fight, heal, and prevent the spread of communicable diseases was unsuccessful for a long time. It was not until the discovery of the healing effects of (antibiotic producing) molds, the first microscopic observations of microorganisms in the seventeenth century, the refutation of the abiogenesis theory, and the dissolution of the question "What is the nature of infectious diseases?" that the first milestones within the history of antibiotics research were set. Then new discoveries accelerated rapidly: Bacteria could be isolated and cultured and were identified as possible agents of diseases as well as producers of bioactive metabolites. At the same time the first synthetic antibiotics were developed and shortly thereafter, thousands of synthetic substances as well as millions of soil borne bacteria and fungi were screened for bioactivity within numerous microbial laboratories of pharmaceutical companies. New antibiotic classes with different targets were discovered as on assembly line production. With the beginning of the twentieth century, many of the diseases which reached epidemic proportions at the time-e.g., cholera, syphilis, plague, tuberculosis, or typhoid fever, just to name a few, could be combatted with new discovered antibiotics. It should be considered that hundred years ago the market launch of new antibiotics was significantly faster and less complicated than today (where it takes 10-12 years in average between the discovery of a new antibiotic until the launch). After the first euphoria it was quickly realized that bacteria are able to develop, acquire, and spread numerous resistance mechanisms

  18. Incidence and antibiotic susceptibility pattern of Staphylococcus ...

    African Journals Online (AJOL)

    Records of microbial cultures and antibiotic sensitivity test results of suspected cases of urinary tract infection (UTI) of the University of. Benin Teaching Hospital (UBTH) Benin City from January 1st to 31st December, 2005 were retrieved and statistically analyzed. Two thousand, one hundred and twelve (2,112) early ...

  19. Addressing resistance to antibiotics in systematic reviews of antibiotic interventions

    NARCIS (Netherlands)

    Leibovici, Leonard; Paul, Mical; Garner, Paul; Sinclair, David J; Afshari, Arash; Pace, Nathan Leon; Cullum, Nicky; Williams, Hywel C; Smyth, Alan; Skoetz, Nicole; Del Mar, Chris; Schilder, Anne G M; Yahav, Dafna; Tovey, David

    Antibiotics are among the most important interventions in healthcare. Resistance of bacteria to antibiotics threatens the effectiveness of treatment. Systematic reviews of antibiotic treatments often do not address resistance to antibiotics even when data are available in the original studies. This

  20. Prescripción de antimicrobianos contra las infecciones del tracto urinario en el adulto mayor Prescription of antibiotics against urinary tract infections in the elderly

    Directory of Open Access Journals (Sweden)

    Lianne Pajarín Fernández

    2012-05-01

    , sulfonamides and beta-lactams. Most prescriptions were inappropriate, mainly because of difficulties in the individualization of treatment, and a high percentage of patients experienced adverse drug reactions, predominantly mild manifestations.

  1. Fighting antibiotic resistance in the intensive care unit using antibiotics.

    Science.gov (United States)

    Plantinga, Nienke L; Wittekamp, Bastiaan H J; van Duijn, Pleun J; Bonten, Marc J M

    2015-01-01

    Antibiotic resistance is a global and increasing problem that is not counterbalanced by the development of new therapeutic agents. The prevalence of antibiotic resistance is especially high in intensive care units with frequently reported outbreaks of multidrug-resistant organisms. In addition to classical infection prevention protocols and surveillance programs, counterintuitive interventions, such as selective decontamination with antibiotics and antibiotic rotation have been applied and investigated to control the emergence of antibiotic resistance. This review provides an overview of selective oropharyngeal and digestive tract decontamination, decolonization of methicillin-resistant Staphylococcus aureus and antibiotic rotation as strategies to modulate antibiotic resistance in the intensive care unit.

  2. EFFECTIVENESS OF MRSA DETECTION METHODS IN THE LABORATORY PRACTICE – A BRIEF REVIEW

    Directory of Open Access Journals (Sweden)

    Neli M. Ermenlieva

    2016-06-01

    Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA are bacteria, responsible for severe and hard-to-manage infections in human. They are resistant to beta-lactam antibiotics – penicillins (methicillin, dicloxacillin, nafcillin, and oxacillin, cephalosporins and carbapenems, but can also be resistant to the new-generation MRSA-active cephalosporins (such as ceftaroline or other groups of antibiotics, including aminoglycosides, macrolides, clindamycin, amphenicols, quinolones and tetracyclines. MRSA bacteria are pandemic and are often isolated in medical practice and nosocomial infections. The MRSA detection is a challenge to any clinical microbiology laboratory and demands implementation of strict protocols for active screening. While more expensive molecular techniques have the potential of offering highly sensitive and rapid results, the cultural methods require longer time but can achieve a comparable sensitivity for lower price.

  3. Determination of aminoglycoside antibiotics using complex compounds of chromotropic acid bisazoderivatives with rare earth ions

    International Nuclear Information System (INIS)

    Alykov, N.M.

    1981-01-01

    Studies of complex formation of bisazo derivatives of chromotropic acid with rare earth ions and aminoglycoside antibiotics have made it possible to choose carboxyarsenazo, orthanyl R and carboxynitrazo as highly sensitive reagents for determining aminoglycoside antibiotics. Conditions have been found for the formation of precipitates of different-ligand complexes containing rare earth ions, bisazo derivatives of chromotropic acid and aminogylcoside antibiotics. A procedure has been worked out of determining the antibiotics in biological samples with carboxyarsenazo [ru

  4. 76 FR 14024 - Draft Guidance for Industry on Non-Penicillin Beta-Lactam Risk Assessment: A CGMP Framework...

    Science.gov (United States)

    2011-03-15

    ... appropriate steps during the manufacturing process to prevent cross-contamination of finished pharmaceuticals... implementing appropriate steps during the manufacturing process to prevent cross-contamination of finished... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2011-D-0104...

  5. 78 FR 22887 - Guidance for Industry on Non-Penicillin Beta-Lactam Drugs: A Current Good Manufacturing Practices...

    Science.gov (United States)

    2013-04-17

    ... for Preventing Cross- Contamination; Availability AGENCY: Food and Drug Administration, HHS. ACTION... require separation of manufacturing facilities to avoid cross-contamination, the only class of products... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2011-D-0104...

  6. Differential fate of erythromycin and beta-lactam resistance genes from swine lagoon waste under different aquatic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, Charles W., E-mail: charles.knapp@strath.ac.u [David Livingstone Centre for Sustainability, Department of Civil Engineering, University of Strathclyde, 50 Richmond Street, Glasgow, G1 1XN (United Kingdom); School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Zhang, Wen; Sturm, Belinda S.M. [Department of Civil, Environmental and Architectural Engineering, University of Kansas, Lawrence, KS 66045 (United States); Graham, David W. [School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Department of Civil, Environmental and Architectural Engineering, University of Kansas, Lawrence, KS 66045 (United States)

    2010-05-15

    The attenuation and fate of erythromycin-resistance-methylase (erm) and extended-spectrum beta-lactamse (bla) genes were quantified over time in aquatic systems by adding 20-L swine waste to 11,300-L outdoor mesocosms that simulated receiving water conditions below intensive agricultural operations. The units were prepared with two different light-exposure scenarios and included artificial substrates to assess gene movement into biofilms. Of eleven genes tested, only erm(B), erm(F), bla{sub SHV} and bla{sub TEM} were found in sufficient quantity for monitoring. The genes disappeared rapidly from the water column and first-order water-column disappearance coefficients were calculated. However, detected gene levels became elevated in the biofilms within 2 days, but then disappeared over time. Differences were observed between sunlight and dark treatments and among individual genes, suggesting that ecological and gene-specific factors play roles in the fate of these genes after release into the environment. Ultimately, this information will aid in generating better predictive models for gene fate. - The disappearance and fate of erythromycin-resistance-methylase and beta-lactamase genes were monitored in outdoor mesocosms under different light conditions.

  7. Crystal structure of tabtoxin resistance protein complexed with acetyl coenzyme A reveals the mechanism for beta-lactam acetylation.

    Science.gov (United States)

    He, Hongzhen; Ding, Yi; Bartlam, Mark; Sun, Fei; Le, Yi; Qin, Xincheng; Tang, Hong; Zhang, Rongguang; Joachimiak, Andrzej; Liu, Jinyuan; Zhao, Nanming; Rao, Zihe

    2003-01-31

    Tabtoxin resistance protein (TTR) is an enzyme that renders tabtoxin-producing pathogens, such as Pseudomonas syringae, tolerant to their own phytotoxins. Here, we report the crystal structure of TTR complexed with its natural cofactor, acetyl coenzyme A (AcCoA), to 1.55A resolution. The binary complex forms a characteristic "V" shape for substrate binding and contains the four motifs conserved in the GCN5-related N-acetyltransferase (GNAT) superfamily, which also includes the histone acetyltransferases (HATs). A single-step mechanism is proposed to explain the function of three conserved residues, Glu92, Asp130 and Tyr141, in catalyzing the acetyl group transfer to its substrate. We also report that TTR possesses HAT activity and suggest an evolutionary relationship between TTR and other GNAT members.

  8. Crystal structure of tabtoxin resistance protein complexed with acetyl coenzyme A reveals the mechanism for {beta}-lactam acetylation.

    Energy Technology Data Exchange (ETDEWEB)

    He, H.; Ding, Y.; Bartlam, M.; Sun, F.; Le, Y.; Qin, X.; Tang, H.; Zhang, R.; Joachimiak, A.; Liu, J.; Zhao, N.; Rao, Z.; Biosciences Division; Tsinghua Univ.; Chinese Academy of Science

    2003-01-31

    Tabtoxin resistance protein (TTR) is an enzyme that renders tabtoxin-producing pathogens, such as Pseudomonas syringae, tolerant to their own phytotoxins. Here, we report the crystal structure of TTR complexed with its natural cofactor, acetyl coenzyme A (AcCoA), to 1.55 {angstrom} resolution. The binary complex forms a characteristic 'V' shape for substrate binding and contains the four motifs conserved in the GCN5-related N-acetyltransferase (GNAT) superfamily, which also includes the histone acetyltransferases (HATs). A single-step mechanism is proposed to explain the function of three conserved residues, Glu92, Asp130 and Tyr141, in catalyzing the acetyl group transfer to its substrate. We also report that TTR possesses HAT activity and suggest an evolutionary relationship between TTR and other GNAT members.

  9. Pharmacokinetic drug interactions of antimicrobial drugs : a systematic review on oxazolidinones, rifamycines, macrolides, fluoroquinolones, and Beta-lactams

    NARCIS (Netherlands)

    Bolhuis, Mathieu S; Panday, Prashant N; Pranger, Arianna D; Kosterink, Jos G W; Alffenaar, Jan-Willem C

    2011-01-01

    Like any other drug, antimicrobial drugs are prone to pharmacokinetic drug interactions. These drug interactions are a major concern in clinical practice as they may have an effect on efficacy and toxicity. This article provides an overview of all published pharmacokinetic studies on drug

  10. Selection of antibiotic resistance at very low antibiotic concentrations

    OpenAIRE

    Sandegren, Linus

    2014-01-01

    Human use of antibiotics has driven the selective enrichment of pathogenic bacteria resistant to clinically used drugs. Traditionally, the selection of resistance has been considered to occur mainly at high, therapeutic levels of antibiotics, but we are now beginning to understand better the importance of selection of resistance at low levels of antibiotics. The concentration of an antibiotic varies in different body compartments during treatment, and low concentrations of antibiotics are fou...

  11. Antibiotic alternatives: the substitution of antibiotics in animal husbandry?

    OpenAIRE

    Cheng, Guyue; Hao, Haihong; Xie, Shuyu; Wang, Xu; Dai, Menghong; Huang, Lingli; Yuan, Zonghui

    2014-01-01

    It is a common practice for decades to use of sub-therapeutic dose of antibiotics in food-animal feeds to prevent animals from diseases and to improve production performance in modern animal husbandry. In the meantime, concerns over the increasing emergence of antibiotic-resistant bacteria due to the unreasonable use of antibiotics and an appearance of less novelty antibiotics have prompted efforts to develop so-called alternatives to antibiotics. Whether or not the alternatives could really ...

  12. Antibiotic-Resistant Gonorrhea

    Science.gov (United States)

    ... Search Form Controls Cancel Submit Search the CDC Gonorrhea Note: Javascript is disabled or is not supported ... on Facebook Sexually Transmitted Diseases (STDs) Antibiotic-Resistant Gonorrhea Recommend on Facebook Tweet Share Compartir Low Resolution ...

  13. Glycopeptide antibiotic biosynthesis.

    Science.gov (United States)

    Yim, Grace; Thaker, Maulik N; Koteva, Kalinka; Wright, Gerard

    2014-01-01

    Glycopeptides such as vancomycin, teicoplanin and telavancin are essential for treating infections caused by Gram-positive bacteria. Unfortunately, the dwindled pipeline of new antibiotics into the market and the emergence of glycopeptide-resistant enterococci and other resistant bacteria are increasingly making effective antibiotic treatment difficult. We have now learned a great deal about how bacteria produce antibiotics. This information can be exploited to develop the next generation of antimicrobials. The biosynthesis of glycopeptides via nonribosomal peptide assembly and unusual amino acid synthesis, crosslinking and tailoring enzymes gives rise to intricate chemical structures that target the bacterial cell wall. This review seeks to describe recent advances in our understanding of both biosynthesis and resistance of these important antibiotics.

  14. Antibiotics for uncomplicated diverticulitis

    DEFF Research Database (Denmark)

    Shabanzadeh, Daniel M; Wille-Jørgensen, Peer

    2012-01-01

    Diverticulitis is an inflammatory complication to the very common condition diverticulosis. Uncomplicated diverticulitis has traditionally been treated with antibiotics with reference to the microbiology, extrapolation from trials on complicated intra-abdominal infections and clinical experience....

  15. Antibiotics for sore throat.

    Science.gov (United States)

    Spinks, Anneliese; Glasziou, Paul P; Del Mar, Chris B

    2013-11-05

    Sore throat is a common reason for people to present for medical care. Although it remits spontaneously, primary care doctors commonly prescribe antibiotics for it. To assess the benefits of antibiotics for sore throat for patients in primary care settings. We searched CENTRAL 2013, Issue 6, MEDLINE (January 1966 to July week 1, 2013) and EMBASE (January 1990 to July 2013). Randomised controlled trials (RCTs) or quasi-RCTs of antibiotics versus control assessing typical sore throat symptoms or complications. Two review authors independently screened studies for inclusion and extracted data. We resolved differences in opinion by discussion. We contacted trial authors from three studies for additional information. We included 27 trials with 12,835 cases of sore throat. We did not identify any new trials in this 2013 update. 1. Symptoms Throat soreness and fever were reduced by about half by using antibiotics. The greatest difference was seen at day three. The number needed to treat to benefit (NNTB) to prevent one sore throat at day three was less than six; at week one it was 21. 2. Non-suppurative complications The trend was antibiotics protecting against acute glomerulonephritis but there were too few cases to be sure. Several studies found antibiotics reduced acute rheumatic fever by more than two-thirds within one month (risk ratio (RR) 0.27; 95% confidence interval (CI) 0.12 to 0.60). 3. Suppurative complications Antibiotics reduced the incidence of acute otitis media within 14 days (RR 0.30; 95% CI 0.15 to 0.58); acute sinusitis within 14 days (RR 0.48; 95% CI 0.08 to 2.76); and quinsy within two months (RR 0.15; 95% CI 0.05 to 0.47) compared to those taking placebo. 4. Subgroup analyses of symptom reduction Antibiotics were more effective against symptoms at day three (RR 0.58; 95% CI 0.48 to 0.71) if throat swabs were positive for Streptococcus, compared to RR 0.78; 95% CI 0.63 to 0.97 if negative. Similarly at week one the RR was 0.29 (95% CI 0.12 to 0

  16. Phenotypic Resistance to Antibiotics

    Directory of Open Access Journals (Sweden)

    Jose L. Martinez

    2013-04-01

    Full Text Available The development of antibiotic resistance is usually associated with genetic changes, either to the acquisition of resistance genes, or to mutations in elements relevant for the activity of the antibiotic. However, in some situations resistance can be achieved without any genetic alteration; this is called phenotypic resistance. Non-inherited resistance is associated to specific processes such as growth in biofilms, a stationary growth phase or persistence. These situations might occur during infection but they are not usually considered in classical susceptibility tests at the clinical microbiology laboratories. Recent work has also shown that the susceptibility to antibiotics is highly dependent on the bacterial metabolism and that global metabolic regulators can modulate this phenotype. This modulation includes situations in which bacteria can be more resistant or more susceptible to antibiotics. Understanding these processes will thus help in establishing novel therapeutic approaches based on the actual susceptibility shown by bacteria during infection, which might differ from that determined in the laboratory. In this review, we discuss different examples of phenotypic resistance and the mechanisms that regulate the crosstalk between bacterial metabolism and the susceptibility to antibiotics. Finally, information on strategies currently under development for diminishing the phenotypic resistance to antibiotics of bacterial pathogens is presented.

  17. Antibiotics produced by Streptomyces.

    Science.gov (United States)

    Procópio, Rudi Emerson de Lima; Silva, Ingrid Reis da; Martins, Mayra Kassawara; Azevedo, João Lúcio de; Araújo, Janete Magali de

    2012-01-01

    Streptomyces is a genus of Gram-positive bacteria that grows in various environments, and its shape resembles filamentous fungi. The morphological differentiation of Streptomyces involves the formation of a layer of hyphae that can differentiate into a chain of spores. The most interesting property of Streptomyces is the ability to produce bioactive secondary metabolites, such as antifungals, antivirals, antitumorals, anti-hypertensives, immunosuppressants, and especially antibiotics. The production of most antibiotics is species specific, and these secondary metabolites are important for Streptomyces species in order to compete with other microorganisms that come in contact, even within the same genre. Despite the success of the discovery of antibiotics, and advances in the techniques of their production, infectious diseases still remain the second leading cause of death worldwide, and bacterial infections cause approximately 17 million deaths annually, affecting mainly children and the elderly. Self-medication and overuse of antibiotics is another important factor that contributes to resistance, reducing the lifetime of the antibiotic, thus causing the constant need for research and development of new antibiotics. Copyright © 2012 Elsevier Editora Ltda. All rights reserved.

  18. Strategies to Minimize Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Sang Hee Lee

    2013-09-01

    Full Text Available Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs and various data such as pharmacokinetic (PK and pharmacodynamic (PD properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST, clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.g., through schools and day care, the public, and relevant healthcare professionals (e.g., primary-care physicians, pharmacists, and medical students regarding unique features of bacterial infections and antibiotics, prudent antibiotic prescribing as a positive construct, and personal hygiene (e.g., handwashing. The problem of antibiotic resistance can be minimized only by concerted efforts of all members of society for ensuring the continued efficiency of antibiotics.

  19. Assessment of antibiotic use in farm animals in Rwanda.

    Science.gov (United States)

    Manishimwe, Rosine; Nishimwe, Kizito; Ojok, Lonzy

    2017-08-01

    The irrational use of antibiotics in humans and animals is highly related to the emergence and increase of antibiotic-resistant bacteria worldwide. A cross-sectional survey aimed at evaluating the current level of practices regarding antibiotic use in farm animals in Rwanda was carried out countrywide. Interviews were conducted on 229 farmers rearing different types of animals. The study has revealed that almost all respondent farmers could name at least one antibiotic used in farm animals and peni-streptomycin was named by most of them (95.6%). The use of antibiotics in farm animals was observed in the majority of respondents (97.4%). It was found that 44.4 and 26.5% of respondents reported that they used antibiotics for disease prevention and growth promotion, respectively. The use of non-prescribed antibiotics in animals was also reported by more than the half of respondent farmers (55.6%). The majority of farmers had a moderate level of practices regarding antibiotic use in farm animals (73.5%), very few had a high level (26%) and only one respondent had a low level. The high level of practices in regard to antibiotic use in animals was associated with the location of the farm, the type of reared animals, and the rearing system. The results of this study give an insight into antibiotics usage practices in farm animals in Rwanda. The generated information can guide sensitizations and promotions of the prudent use of antibiotics among farmers in order to limit the increase of antibiotic resistance in the country.

  20. Antibiotics impact plant traits, even at small concentrations

    Science.gov (United States)

    Deloy, Andrea; Volkert, Anna Martina; Leonhardt, Sara Diana; Pufal, Gesine

    2017-01-01

    Abstract Antibiotics of veterinary origin are released to agricultural fields via grazing animals or manure. Possible effects on human health through the consumption of antibiotic exposed crop plants have been intensively investigated. However, information is still lacking on the effects of antibiotics on plants themselves, particularly on non-crop species, although evidence suggests adverse effects of antibiotics on growth and performance of plants. This study evaluated the effects of three major antibiotics, penicillin, sulfadiazine and tetracycline, on the germination rates and post-germinative traits of four plant species during ontogenesis and at the time of full development. Antibiotic concentrations were chosen as to reflect in vivo situations, i.e. concentrations similar to those detected in soils. Plant species included two herb species and two grass species, and represent two crop-species and two non-crop species commonly found in field margins, respectively. Germination tests were performed in climate chambers and effects on the remaining plant traits were determined in greenhouse experiments. Results show that antibiotics, even in small concentrations, significantly affect plant traits. These effects include delayed germination and post-germinative development. Effects were species and functional group dependent, with herbs being more sensitive to antibiotics then grasses. Responses were either negative or positive, depending on plant species and antibiotic. Effects were generally stronger for penicillin and sulfadiazine than for tetracycline. Our study shows that cropland species respond to the use of different antibiotics in livestock industry, for example, with delayed germination and lower biomass allocation, indicating possible effects on yield in farmland fertilized with manure containing antibiotics. Also, antibiotics can alter the composition of plant species in natural field margins, due to different species-specific responses, with unknown

  1. Antibiotics for acute bronchitis.

    Science.gov (United States)

    Smith, Susan M; Fahey, Tom; Smucny, John; Becker, Lorne A

    2017-06-19

    The benefits and risks of antibiotics for acute bronchitis remain unclear despite it being one of the most common illnesses seen in primary care. To assess the effects of antibiotics in improving outcomes and to assess adverse effects of antibiotic therapy for people with a clinical diagnosis of acute bronchitis. We searched CENTRAL 2016, Issue 11 (accessed 13 January 2017), MEDLINE (1966 to January week 1, 2017), Embase (1974 to 13 January 2017), and LILACS (1982 to 13 January 2017). We searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov on 5 April 2017. Randomised controlled trials comparing any antibiotic therapy with placebo or no treatment in acute bronchitis or acute productive cough, in people without underlying pulmonary disease. At least two review authors extracted data and assessed trial quality. We did not identify any new trials for inclusion in this 2017 update. We included 17 trials with 5099 participants in the primary analysis. The quality of trials was generally good. At follow-up there was no difference in participants described as being clinically improved between the antibiotic and placebo groups (11 studies with 3841 participants, risk ratio (RR) 1.07, 95% confidence interval (CI) 0.99 to 1.15). Participants given antibiotics were less likely to have a cough (4 studies with 275 participants, RR 0.64, 95% CI 0.49 to 0.85; number needed to treat for an additional beneficial outcome (NNTB) 6) and a night cough (4 studies with 538 participants, RR 0.67, 95% CI 0.54 to 0.83; NNTB 7). Participants given antibiotics had a shorter mean cough duration (7 studies with 2776 participants, mean difference (MD) -0.46 days, 95% CI -0.87 to -0.04). The differences in presence of a productive cough at follow-up and MD of productive cough did not reach statistical significance.Antibiotic-treated participants were more likely to be improved according to clinician's global assessment (6 studies

  2. Carbapenem-non-susceptible Enterobacteriaceae in Europe : conclusions from a meeting of national experts

    NARCIS (Netherlands)

    Grundmann, H.; Livermore, D. M.; Giske, C. G.; Canton, R.; Rossolini, G. M.; Campos, J.; Vatopoulos, A.; Gniadkowski, M.; Toth, A.; Pfeifer, Y.; Jarlier, V.; Carmeli, Y.

    2010-01-01

    The emergence and global spread of carbapenemase-producing Enterobacteriaceae is of great concern to health services worldwide. These bacteria are often resistant to all beta-lactam antibiotics and frequently co-resistant to most other antibiotics, leaving very few treatment options. The

  3. MRSA Breast Abscesses in Postpartum Women

    Directory of Open Access Journals (Sweden)

    E.W.L. Chuwa

    2009-01-01

    Conclusion: CA-MRSA is an emerging problem in our obstetric population. CA-MRSA breast infections are clinically responsive to common oral antibiotics such as co-trimoxazole and erythromycin. A high index of suspic